Publications

There is a great demand for efficient electromagnetic interference (EMI) shielding materials due to exponential growth in wireless telecommunication devices. These devices emit electromagnetic radiation that can disrupt electronic devices, and cause health hazards. Therefore, it is crucial to develop materials that can shield devices and humans from exposure to electromagnetic radiation. In this context, nanocomposite materials offer huge advantages due to the dual possibility of tailoring the interfaces as well as using the complementary properties of magnetic and dielectric components in the nanocomposite to enhance the EMI shielding performance. This work shows that by a careful tuning of the synthesis parameters, we can grow biphasic lithium iron oxide (ferrimagnetic α-LiFe₅O₈ and paramagnetic α-LiFeO₂) nanocomposite with different relative fractions of the two phases. The variation of the phase fraction and the simultaneous growth of the two phases allow us to control the interfaces between the two phases as well as the physical properties of the nanocomposite, which have a direct effect on the EMI shielding performance. Detailed structural (X-ray diffraction), compositional (Raman spectroscopy), and morphological (high-resolution transmission electron microscopy) characterization is presented to understand the effect of the synthesis conditions on the EMI shielding parameters. Improved dielectric and magnetic properties together with an increased number of interfaces in the sample with nearly equal amounts of the two phases results in the best performance. This work demonstrates the significant potential of using biphasic magnetic oxide nanocomposites with controllable interfaces and physical properties for EMI shielding, which can form the base for more complex triphasic systems in the future.

Spinels represent a class of ceramics with promising fundamental properties and a broad spectrum of industrial applications. However, the knowledge of pressure effects on the crystal structure of spinel is limited, which hinders their efficient synthesis using high-pressure techniques. In this paper, the effect of pressure on the crystal structure of mixed spinel ferrite Fe_0.8Ni_1.8Sb_0.4O₄ was investigated at room temperature by in situ synchrotron-based X-ray diffraction and Raman spectroscopy up to 42.19 GPa and 49.51 GPa, respectively. The X-ray diffraction results indicate that Fe_0.8Ni_1.8Sb_0.4O₄ adopts the cubic (spinel-type, space group Fd 3¯ m) structure at ambient conditions, which undergoes a pressure-induced structural transition to a monoclinic phase (space group P2₁/c), commencing at 20.83 GPa. This sluggish structural transformation turns out to be of the first-order accompanied by a volume collapse of about ∼2.2 % when completed at 29.68 GPa. A second phase transition to yet another metastable monoclinic structure with space group C2/m is observed to begin at 33.56 GPa. However, this phase transition does not complete even up to the highest pressure applied in the study. Raman results confirm that Fe_0.8Ni_1.8Sb_0.4O₄ undergoes a pressure-induced phase transition from Fd 3¯ m to P2₁/c at 27.34 GPa. The observed phase transitions are reversible, and their mechanisms are discussed in the light of the Raman spectroscopy data. The present study deepens our understanding of the high-pressure behavior of spinels, which will facilitate their industrial syntheses and a better understanding of their role in planetary interiors.

Background: The effects of obesity on pulmonary gas and blood distribution in patients with acute respiratory failure remain unknown. Dual-energy computed tomography (DECT) is a X-ray-based method used to study regional distribution of gas and blood within the lung. We hypothesized that 1) regional gas/blood mismatch can be quantified by DECT; 2) obesity influences the global and regional distribution of pulmonary gas and blood; 3) regardless of ventilation modality (invasive vs. non-invasive ventilation), patients’ body mass index (BMI) has an impact on pulmonary gas/blood mismatch.

Methods: This single-centre prospective observational study enrolled 118 hypoxic COVID-19 patients (92 male) in need of respiratory support and intensive care who underwent DECT. The cohort was divided into three groups according to BMI: 1. BMI<25 kg/m² (non-obese), 2. BMI = 25–40 kg/m² (overweight to obese), and 3. BMI>40 kg/m² (morbidly obese). Gravitational analysis of Hounsfield unit distribution of gas and blood was derived from DECT and used to calculate regional gas/blood mismatch. A sensitivity analysis was performed to investigate the influence of the chosen ventilatory modality and BMI on gas/blood mismatch and adjust for other possible confounders (i.e., age and sex).

Results: 1) Regional pulmonary distribution of gas and blood and their mismatch were quantified using DECT imaging. 2) The BMI>40 kg/m² group had less hyperinflation in the non-dependent regions and more lung collapse in the dependent regions compared to the other BMI groups. In morbidly obese patients, gas and blood were more evenly distributed; therefore, the mismatch was lower than in other patients (30% vs. 36%, p < 0.05). 3) An increase in BMI of 5 kg/m² was associated with a decrease in mismatch of 3.3% (CI: 3.67% to −2.93%, p < 0.05). Neither the ventilatory modality nor age and sex affected the gas/blood mismatch (p > 0.05).

Conclusion: 1) In a hypoxic COVID-19 population needing intensive care, pulmonary gas/blood mismatch can be quantified at a global and regional level using DECT. 2) Obesity influences the global and regional distribution of gas and blood within the lung, and BMI>40 kg/m² improves pulmonary gas/blood mismatch. 3) This is true regardless of the ventilatory mode and other possible confounders, i.e., age and sex.

Trial Registration: Clinicaltrials.gov, identifier NCT04316884, NCT04474249.

Collision induced unfolding is method used with ion mobility mass spectrometry to examine protein structures and their stability. Such experiments yield information about higher order protein structures, yet are unable to provide details about the underlying processes. That information can however be provided using molecular dynamics simulations. Here, we investigate the collision induced unfolding of norovirus capsid dimers from the Norwalk and Kawasaki strains by employing molecular dynamics simulations over a range of temperatures, representing different levels of activation. The dimers have highly similar structures, but the activation reveals differences in the dynamics that arises in response to the activation.

High-quality crystals of CoTeO₄ were grown by application of chemical vapor transport reactions in closed silica ampoules, starting from polycrystalline material in a temperature gradient 640 °C → 580 °C with TeCl₄ as transport agent. Crystal structure analysis of CoTeO₄ from single crystal X-ray data revealed a dirutile-type structure with Co^II and Te^VI atoms at crystallographically distinct sites, each with point group symmetry . The statistical significance and accuracy of the previously reported structural model based on powder data with the ordered arrangement of Co and Te cations was noticeably improved. CoTeO₄ does not undergo a structural phase transition upon heating, but decomposes stepwise (Co₂Te₃O₈ as intermediate phase) to Co₃TeO₆ as the only crystalline phase stable above 770 °C. Temperature-dependent magnetic susceptibility and dielectric measurements suggest antiferromagnetic ordering at ∼50 K. Optical absorption spectroscopy and computational studies reveal wide-band semiconductive behavior for CoTeO₄. The experimentally determined band gap of ∼2.42 eV is also found for CdS, which is frequently used in photovoltaic systems but is hazardous to the environment. Hence, CoTeO₄ might be a possible candidate to replace CdS in this regard.

In this study, we investigate the influence of Cr-Cr distances on the magnetic properties of triangular lattice antiferromagnets through the lens of the recently synthesized Cr compounds LiCrSe₂, LiCrTe₂, and NaCrTe₂. Our comprehensive analysis integrates existing magnetic structure data and new insights from muon spin rotation measurements, revealing a striking mutual influence between strongly correlated electrons and structural degrees of freedom in systems possessing very different magnetic properties despite having the same crystal symmetry. In particular, we delineate how Cr-Cr distances specifically dictate the magnetic behaviors of the triangular lattice antiferromagnets LiCrSe₂, LiCrTe₂, and NaCrTe₂. By crafting phase diagrams based on these distances, we establish a clear correlation between the structural parameters and the magnetic ground states of these materials together with a wide variety of trivalent Cr triangular lattice layered magnets. Our analysis uncovers a transition range for in-plane and out-of-plane Cr-Cr distances that demarcates distinct magnetic behaviors, highlighting the nuanced role of lattice geometry in the spin-lattice interaction and electron correlation dynamics.

The synthetic availability of mol­ecular water oxidation catalysts containing high-valent ions of 3d metals in the active site is a prerequisite to enabling photo- and electrochemical water splitting on a large scale. Herein, the synthesis and crystal structure of di­ammonium {μ-1,3,4,7,8,10,12,13,16,17,19,22-dodeca­aza­tetra­cyclo­[8.8.4.13,17.18,12]tetra­cosane-5,6,14,15,20,21-hexa­onato}ferrate(IV) acetic acid tris­olvate, (NH4)2[FeIV(C12H12N12O6)]·3CH3COOH or (NH4)2[FeIV(L–6H)]·3CH3COOH is reported. The FeIV ion is encapsulated by the macropolycyclic ligand, which can be described as a dodeca-aza-quadricyclic cage with two capping tri­aza­cyclo­hexane fragments making three five- and six six-membered alternating chelate rings with the central FeIV ion. The local coord­ination environment of FeIV is formed by six deprotonated hydrazide nitro­gen atoms, which stabilize the unusual oxidation state. The FeIV ion lies on a twofold rotation axis (multiplicity 4, Wyckoff letter e) of the space group C2/c. Its coordination geometry is inter­mediate between a trigonal prism (distortion angle φ = 0°) and an anti­prism (φ = 60°) with φ = 31.1°. The Fe—N bond lengths lie in the range 1.9376 (13)–1.9617 (13) Å, as expected for tetra­valent iron. Structure analysis revealed that three acetic acid mol­ecules additionally co-crystallize per one iron(IV) complex, and one of them is positionally disordered over four positions. In the crystal structure, the ammonium cations, complex dianions and acetic acid mol­ecules are inter­connected by an intricate system of hydrogen bonds, mainly via the oxamide oxygen atoms acting as acceptors.

Phase retrieval is an important optimization problem that occurs, for example, in the analysis of coherent diffraction patterns from isolated proteins. All iterative algorithms employed for phase retrieval in this context require some a priori knowledge of the object, usually in the form of a support that describes the extent of the particle. Phase retrieval is a time-consuming task that can often fail, particularly if the support is too loose or of bad quality. This paper presents a neural network that can produce low-resolution estimates of the phased object in a fraction of the time it takes for a full phase retrieval. It can also successfully be used as support for further analysis. Our network is trained on simulated data from biological macromolecules and is thus tailored to the type of data seen in a typical CDI experiment. Other approaches to support finding require very accurate data without missing regions or the full phase-retrieval algorithm to be run for a long time. Our network could speed up offline analysis and provide real-time feedback during data collection.

The nature of the magma plumbing system of Large Igneous Provinces is still poorly understood. Among these exceptional magmatic events from Earth's past, the end-Triassic Central Atlantic Magmatic Province (CAMP) and the end-Cretaceous Deccan Traps (Deccan) coincided in time with two of the most catastrophic biotic crises during the Phanerozoic. In order to constrain the architecture of their magma plumbing system, glomerocrysts containing abundant bubble-bearing melt inclusions from basaltic lava flows of both CAMP and Deccan were investigated via in situ geochemical and microstructural analyses. The analysed glomerocrysts, dominated by augitic clinopyroxene crystals, represent fragments of a crystal mush entrained by basaltic magmas before eruption. The analysed melt inclusions, consisting of an intermediate to felsic composition glass and CO₂-bearing bubbles, represent relics of interstitial melts and fluids within a porous crystal framework forming the crystal mush. The different volume proportions between bubbles and whole inclusions reveal that melt entrapment occurred after volatile exsolution. The minimum observed bubble/inclusion fraction indicates that the CO2 concentration in CAMP and Deccan melts was at least 0.3 wt.%, consistent with a maximum entrapment pressure of about 0.5 GPa at CO₂-H₂O fluid-saturated conditions. The MgO-rich composition of host clinopyroxene crystals and whole rocks is in contrast with the SiO₂-rich composition of (trachy-) andesitic to rhyolitic glass of melt inclusions, pointing to disequilibrium conditions. Thermodynamic and geochemical modelling shows that fractional crystallization alone cannot explain the evolved composition of glass in melt inclusions starting from their whole rock composition. On one side, the oxygen isotope composition of clinopyroxene crystals in glomerocrysts ranges from +3.9 (± 0.3) to +5.8 (± 0.3) ‰ and their sample-averaged oxygen isotope composition spans from +4.4 (N = 10) to +5.6 (N = 10) ‰, implying that glomerocrysts crystallized from mafic melts with normal (i.e., mantle-like) to slightly low delta 18O values. On the other side, the oxygen isotope composition of glass in melt inclusions ranges from +5.5 (± 0.4) to +22.1 (± 0.4) parts per thousand, implying that melt inclusions entrapped intermediate to felsic melts with normal (i.e., mantle-like) to extremely high δ¹⁸O values, typical of (meta-) sedimentary rocks. Some melt inclusions are compatible with fractionation from the same mafic melts that crystallized their host mineral phase, but most melt inclusions are compatible with variable degrees of crustal assimilation and partial mixing, potentially followed by minor post-entrapment isotope re-equilibration. In the CAMP, where sedimentary basins are abundant, (meta-) pelites and occasionally granitoids were the most likely assimilants. On the contrary, in the Deccan, where sedimentary basins are rare, granitoids and metapelites were the most likely assimilants. Oxygen isotope compositions of glass in melt inclusions, spanning from mantle-like to crust-dominated signatures, suggest that the CO2 within their coexisting bubbles likely derived partly from the mantle and partly from assimilated crustal materials. The investigated glomerocrysts and their bubble-bearing melt inclusions are relics of a multiphase (i.e. , solid + liquid + gas phases) crystal mush revealing a dynamic evolution for the magma plumbing system of both CAMP and Deccan, where crystals, silicate melts and exsolved fluids coexisted and interacted through most of the transcrustal section.

We evaluate a method to quantify composition depth gradients in intact metal–organic framework (MOF) single crystals and thereby derive diffusion coefficients of postsynthetically incorporated active sites by nondestructive ion-beam microanalysis. Zr-based UiO-67-bpy (bpy = 2,2′-bipyridine-5,5′-dicarboxylic acid) MOFs were synthesized on Si substrates and then metalated postsynthetically with NiCl₂ for 2–48 h, resulting in different Ni depth distributions. Simultaneous micro-Rutherford backscattering spectrometry (μ-RBS) and micro-particle induced X-ray emission (μ-PIXE) analysis were used for the spatially resolved chemical analysis of the MOF single crystals. Qualitative assessment of the μ-RBS spectra indicated the presence of elemental depth gradients and hinted at the governing process of the postsynthetic Ni incorporation, in the present case, molecular diffusion. Quantitative evaluation of the resulting composition depth profiles directly provided the diffusion length and, thereby, the diffusion coefficient of the system. Virtual gradients caused by overhanging tips/edges of the truncated octahedral crystal shape are considered. Furthermore, in the case of insufficient probing depth for μ-RBS, μ-PIXE was still capable of providing qualitative information. In the present system the diffusion coefficient for NiCl₂ is found to be (1.72 ± 0.18) × 10^–16 m²s^–1. The long-term stability of the synthesized and postsynthetically modified MOFs is proved by repeated measurements.

The present study investigates the photofragmentation behavior of iodine-enhanced nitroimidazole-based radiosensitizer model compounds in their protonated form using near-edge X-ray absorption mass spectrometry and quantum mechanical calculations. These molecules possess dual functionality: improved photoabsorption capabilities and the ability to generate species that are relevant to cancer sensitization upon photofragmentation. Four samples were investigated by scanning the generated fragments in the energy regions around C 1s, N 1s, O 1s, and I 3d-edges with a particular focus on NO2+ production. The experimental summed ion yield spectra are explained using the theoretical near-edge X-ray absorption fine structure spectrum based on density functional theory. Born-Oppenheimer-based molecular dynamics simulations were performed to investigate the fragmentation processes.

U(VI) in natural pyromorphite reaches 0.5 wt%. However, this depends on concentration of U in source solutions and the upper limit of incorporation of uranyl into pyromorphite at low temperature is unknown. If U(VI) incorporation capacity in the structure is high enough, Pb-apatite could be used in radioactive waste remediation. In this study, eight compounds were synthesized from aqueous solutions containing Pb²⁺, (UO₂)²⁺, (PO₄)^3- and Cl^- ions in a still water column under ambient conditions. In each synthesis, the molar ratio of (UO₂)²⁺:Pb was varied, targeting composition Pb_5-x(UO₂)_x(PO₄)₃Cl. The final solutions were analyzed with inductively coupled plasma optical emission spectroscopy (ICP-OES) for Pb and U(VI) concentrations, while dried solids were analyzed using powder X-ray diffraction (PXRD), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), wavelength dispersive X-ray spectroscopy (WDS) using an electron microprobe, and Raman spectroscopy. Synthesis products are synthetic analogs of pyromorphite containing (UO₂)²⁺, partially substituting Pb²⁺. For the higher initial concentration of U, coprecipitation of a second phase/phases was observed. U was removed from the solution at levels ranging from 74.3 % (σ = 1.5) to 88 % (σ = 2), and Pb was removed at levels ranging from 91 % (σ = 2) to 96.8 % (σ = 1.9). Precipitation of pyromorphite from uranyl-contaminated solutions may immobilize uranyl in the form of highly insoluble, stable, crystalline Pb phosphates.

BACKGROUND AND AIMS: Non-HDL-C provides an estimate of lipid-associated risk and is a secondary treatment target after myocardial infarction (MI). The aim was to study the relationship between non-HDL-C levels after MI and risk of adverse outcomes.

METHODS: From the SWEDEHEART registry, 56 262 patients with MI were included. Outcomes were major adverse cardiovascular event (MACE: death, MI, and ischaemic stroke), death, and non-fatal MI. Non-HDL-C was assessed at admission, 2 months, and 1 year. Target achievement (<2.2 mmol/L) of non-HDL-C, timing thereof, and outcomes were assessed.

RESULTS: During median follow-up of 5.4 years, 9549 had MACE, 5427 died, and 3946 had MI. Long-term hazard ratio (HR) for MACE in the lowest vs. the highest quartile of achieved non-HDL-C at 1 year was 0.76 [95% confidence interval (CI) 0.71-0.81]. Short-term results were consistent also when assessing non-HDL-C levels at 2 months, including early events up to 1 year (HR 0.80, 95% CI 0.68-0.92). Similar results were observed for all outcomes. Patients achieving both early and sustained targets had lowest risk of outcomes (HR 0.80, 95% CI 0.74-0.86) vs. patients achieving target early or late (HR for both 0.86, 95% CI 0.79-0.93).

CONCLUSIONS: The lowest achieved levels both at 2 months and at 1 year of non-HDL-C were associated with better outcome. The lowest risk was observed when target was achieved within 2 months of MI and sustained thereafter. These findings challenge the current stepwise approach for cholesterol lowering after MI, which inevitably results in delaying goal attainment and possible harm.

Stoichiometric Ti_0.33-xAl_xB_0.67 coatings with x = 0.04, 0.15, 0.21, and 0.28 were synthesized by magnetron sputtering and characterized regarding phase formation, mechanical properties, and oxidation behavior. By increasing the Al concentration from 4 to 28 at.%, the measured elastic modulus (496±19 GPa) and unit cell volume (25.646 ų ) decreased by 33 and 0.8 %, respectively. The Al concentration induced changes in measured elastic modulus and unit cell volume are in very good agreement with ab initio predictions, as the maximum deviations between experiment and theory, observed here, are 12 and 1.1 %, respectively. The corresponding hardness values decreased by 45 % from 22±1 to 12±1 GPa. The oxidation experiments were performed in ambient air at 700, 800, and 900 °C for 1, 4, and 8 h. Analysis by scanning transmission electron microscopy (STEM) revealed a bimodal, strongly Al concentration-dependent oxidation behavior where films containing ≤15 at.% of Al form a porous, non-passivating crystalline oxide scale containing Ti -rich as well as Al -rich oxide regions, while the formation of a passivating, dense, X-ray amorphous oxide scale was observed for films containing ≥ 21 at.% of Al. Coincident with the passive scale formation for Al concentrations ≥ 21 at.%, the elastic modulus decreases by ≥ 32.6 % compared to TiB₂ and can be rationalized based on Al concentration induced bond weakening as revealed by the concomitant cohesive energy reduction of ≥ 22 %.

Two new cyanido-bridged {Fe^IIM^II} double chains were obtained by reacting cyanido anions [M(CN)₄]²⁻ with complex cations [Fe^II(tptz)]²⁺ (preformed in situ by mixing a hydrated tetrafluoroborate salt of iron(II) and a tptz ligand, tptz = 2,4,6-tri(2-pyridyl)-1,3,5-triazine) having the general formula [Fe^II(tptz)M^II(CN)₄]·2H₂O·CH₃CN, where M = Pd (1) or Pt (2). Additionally, two molecular complexes formulated as [Fe^II(tptz)₂][M^II(CN)₄]·4.25H₂O, where M = Pd (3) or Pt (4), were subsequently obtained from the same reaction, as secondary products. Single crystal X-ray analysis revealed that 1 and 2 are isostructural and crystallize in the P-1 triclinic space group. Their structure consists of a double-chain with a ladder-like topology, in which cyanido-based [M(CN)₄]²⁻ metalloligands coordinate, through three CN⁻ ligands and three [Fe^II(tptz)]²⁺ complex cations. Compounds 3 and 4 are also isostructural and crystallize in the P triclinic space group, and the X-ray structural data show the formation of [Fe^II(tptz)₂]²⁺ and [M^II(CN)₄]²⁻ ionic units interconnected through H-bonds and π⋯π stacking supramolecular interactions. The static DC magnetic measurements recorded in the temperature range of 2–300 K showed that 1 and 2 exhibit incomplete spin transition on cooling, which is also confirmed by single crystal XRD analysis and Mössbauer spectroscopy. Compounds 3 and 4 are diamagnetic, most likely due to the encapsulation of Fe(II) in a tight pocket formed by two tptz ligands that preserve the low-spin state in the temperature range of 2–400 K.

The work in this dissertation is devoted to investigating order and interfaces in epitaxial heterostructures. To achieve that the software tool box GenL was developed for simulating and fitting x-ray diffraction patterns from epitaxial thin films, which is used to access structural information on the length scales of interfaces and atomic bonds. Employing GenL, it is shown that a small lattice mismatch between substrate and epitaxial layer is not the sole origin of high crystal quality, as demonstrated for nearly strain-free epitaxial growth of tungsten on sapphire with a lattice mismatch of up to 19.4 %. Furthermore, it is discussed that electronic states at the substrate/film interface can have substantial significance for the crystal structure of an epitaxial layer. For instance, despite a nearly mismatch-free interface of body-centered cubic iron on spinel, the presence of a boundary-induced interface layer with tetragonally distorted crystal structure is discovered, which has a profound impact on the magnetic properties. Finally, when creating multilayered structures, not only the interface states but the total structure is found to influence the physical properties, which is demonstrated for the interlayer exchange coupling in [Fe/MgO]_Nsuperlattices.

Note: This PhD thesis is partly based on the licentiate dissertation "Growth of high quality Fe thin films" by Anna L. Ravensburg, Uppsala University, 2022. Particularly parts of: Chapter 1, Sections 2.0, 2.1, 2.2, 3.0, 3.1, 3.2, 3.3, 5.1, and Fig. 2.6 are adapted from the licentiate thesis with minor edits and updates.

Four new compositionally complex perovskites with multiple (four or more) cations on the B site of the perovskites have been studied. The materials have the general formula La_0.5Sr_2.5(M)₂O_7−δ (M = Ti, Mn, Fe, Co, and Ni) and have been synthesized via conventional solid-state synthesis. The compounds are the first reported examples of compositionally complex n = 2 Ruddlesden–Popper perovskites. The structure and properties of the materials have been determined using powder X-ray diffraction, neutron diffraction, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and magnetometry. The materials are isostructural and adopt the archetypal I4/mmm space group with the following unit cell parameters: a ∼ 3.84 Å, and c ∼ 20.1 Å. The measured compositions from energy dispersive X-ray spectroscopy were La_0.51(2)Sr_2.57(7)Ti_0.41(2)Mn_0.41(2)Fe_0.39(2)Co_0.38(1)Ni_0.34(1)O_7−δ, La_0.59(4)Sr_2.29(23)Mn_0.58(5)Fe_0.56(6)Co_0.55(6)Ni_0.42(4)O_7−δ, La_0.54(2)Sr_2.49(13)Mn_0.41(2)Fe_0.81(5)Co_0.39(3)Ni_0.36(3)O_7−δ, and La_0.53(4)Sr_2.55(19)Mn_0.67(6)Fe_0.64(5)Co_0.31(2)Ni_0.30(3)O_7−δ. No magnetic contribution is observed in the neutron diffraction data, and magnetometry indicates a spin glass transition at low temperatures.

The origin of high-energy galactic cosmic rays is yet to be understood, but some galactic cosmic-ray accelerators can accelerate cosmic rays up to PeV energies. The high-energy cosmic rays are expected to interact with the surrounding material or radiation, resulting in the production of gamma-rays and neutrinos. To optimize for the detection of such associated production of gamma-rays and neutrinos for a given source morphology and spectrum, a multimessenger analysis that combines gamma-rays and neutrinos is required. In this study, we use the Multi-Mission Maximum Likelihood framework with IceCube Maximum Likelihood Analysis software and HAWC Accelerated Likelihood to search for a correlation between 22 known gamma-ray sources from the third HAWC gamma-ray catalog and 14 yr of IceCube track-like data. No significant neutrino emission from the direction of the HAWC sources was found. We report the best-fit gamma-ray model and 90% CL neutrino flux limit from the 22 sources. From the neutrino flux limit, we conclude that, for five of the sources, the gamma-ray emission observed by HAWC cannot be produced purely from hadronic interactions. We report the limit for the fraction of gamma-rays produced by hadronic interactions for these five sources.

Temperature-dependent dc-magnetization and ac-susceptibility curves have been recorded for series of single and double layered Ruddlesden-Popper multicomponent perovskites with chemical formula A₂BO₄ and A₃B₂O₇, respectively, with (La, Sr) on A-sites and up to 7 different cations on the B-sites (Ti, Cr, Mn, Fe, Co, Ni, Cu). The phase purity and chemical homogeneity of the compounds were investigated by X-ray diffraction and energy dispersive X-ray spectroscopy. Independently of the composition, spin glassiness is observed in both systems. Scaling analyses suggest the materials undergo spin glass phase transitions at low temperatures. Yet, qualitative differences are observed between the single-layered and double-layered systems, which are discussed in the light of the spatial dimensionality and magnetic interaction in layered oxide perovskites.

Two-dimensional (2D) semiconducting dichalcogenides hold exceptional promise for next-generation electronic and photonic devices. Despite this potential, the pervasive presence of defects in 2D dichalcogenides results in carrier mobility and photoluminescence (PL) that fall significantly short of theoretical predictions. Although defect passivation offers a potential solution, its effects have been inconsistent. This arises from the lack of chemical understanding of the surface chemistry of the 2D material. In this work, we uncover new binding chemistry using a sequence-specific chemical passivation (SSCP) protocol based on 2-furanmethanothiol (FSH) and bis(trifluoromethane) sulfonimide lithium salt (Li-TFSI), which demonstrates a synchronized 100-fold enhancement in both carrier mobility and PL in WS₂ monolayers. We propose an atomic-level synergistic defect passivation mechanism of both neutral and charged sulfur vacancies (SVs), supported by ultrafast transient absorption spectroscopy (TA), Hard X-ray photoelectron spectroscopy (HAXPES), and density functional theory (DFT) calculations. Our results establish a new semiconductor quality benchmark for 2D WS₂, paving the way for the development of sustainable 2D semiconductor technologies.

A series of c-TiAlN/ h-Cr2N multilayer films with modulation periods Lambda of 10, 20 and 30 nm and thickness ratios (Cr2N thickness /Lambda) of 25%, 50% and 75% were prepared by dc magnetron sputtering on the Si substrate. The microstructures were characterized by scanning electron microscopy, x-ray diffraction, and the mechanical properties were measured by curvature measurement method and nanoindentation. With the Cr2N ratio increasing from 25% to 75%, the orientation of Cr2N layers changed from a randomly orientation to a 0001 preferential orientation, while inversely, the c-TiAlN layer changed from a 001 preferential orientation to a 111 preferential orientation or a randomly orientation. In the meantime, and regardless of the modulation period, the lattice parameter of c-TiAlN decreased from 4.16 angstrom to 4.12 angstrom and was explained by an increase of tensile stress between + 0.2 and + 1.3 GPa when the increase of Cr2N% in the modulation. With the increase of Cr2N ratio, the morphology of the film changed and led to surface with apparent porosity and large grain sizes of 100 x 300 nm. The film with 25% Cr2N ratio and modulation period of 20 nm exhibited the highest hardness reaching 22 +/- 1.3 GPa and reduced Young's modulus of 253 +/- 6 GPa.

Water and ice are routinely studied with X-rays to reveal their diverse structures and anomalous properties. We employ a hybrid collisional-radiative/molecular-dynamics method to explore how femtosecond X-ray pulses interact with hexagonal ice. We find that ice makes a phase transition into a crystalline plasma where its initial structure is maintained up to tens of femtoseconds. The ultrafast melting process occurs anisotropically, where different geometric configurations of the structure melt on different time scales. The transient state and anisotropic melting of crystals can be captured by X-ray diffraction, which impacts any study of crystalline structures probed by femtosecond X-ray lasers.

Heavy-fermion metals are prototype systems for observing emergent quantum phases driven by electronic interactions1-6. A long-standing aspiration is the dimensional reduction of these materials to exert control over their quantum phases7-11, which remains a significant challenge because traditional intermetallic heavy-fermion compounds have three-dimensional atomic and electronic structures. Here we report comprehensive thermodynamic and spectroscopic evidence of an antiferromagnetically ordered heavy-fermion ground state in CeSiI, an intermetallic comprising two-dimensional (2D) metallic sheets held together by weak interlayer van der Waals (vdW) interactions. Owing to its vdW nature, CeSiI has a quasi-2D electronic structure, and we can control its physical dimension through exfoliation. The emergence of coherent hybridization of f and conduction electrons at low temperature is supported by the temperature evolution of angle-resolved photoemission and scanning tunnelling spectra near the Fermi level and by heat capacity measurements. Electrical transport measurements on few-layer flakes reveal heavy-fermion behaviour and magnetic order down to the ultra-thin regime. Our work establishes CeSiI and related materials as a unique platform for studying dimensionally confined heavy fermions in bulk crystals and employing 2D device fabrication techniques and vdW heterostructures12 to manipulate the interplay between Kondo screening, magnetic order and proximity effects.

Innovations in resistive switching devices constitute a core objective for the development of ultralow-power computing devices. Forming-free resistive switching is a type of resistive switching that eliminates the need for an initial high voltage for the formation of conductive filaments and offers promising opportunities to overcome the limitations of traditional resistive switching devices. Here, we demonstrate mixed charge state oxygen vacancy-engineered electroforming-free resistive switching in NiFe₂O₄ (NFO) thin films, fabricated as asymmetric Ti/NFO/Pt heterostructures, for the first time. Using pulsed laser deposition in a controlled oxygen atmosphere, we tune the oxygen vacancies together with the cationic valence state in the nickel ferrite phase, with the latter directly affecting the charge state of the oxygen vacancies. The structural integrity and chemical composition of the films are confirmed by X-ray diffraction and hard X-ray photoelectron spectroscopy, respectively. Electrical transport studies reveal that resistive switching characteristics in the films can be significantly altered by tuning the amount and charge state of the oxygen vacancy concentration during the deposition of the films. The resistive switching mechanism is seen to depend upon the migration of both singly and doubly charged oxygen vacancies formed as a result of changes in the nickel valence state and the consequent formation/rupture of conducting filaments in the switching layer. This is supported by the existence of an optimum oxygen vacancy concentration for efficient low-voltage resistive switching, below or above which the switching process is inhibited. Along with the filamentary switching mechanism, the Ti top electrode also enhances the resistive switching performance due to interfacial effects. Time-resolved measurements on the devices display both long- and short-term potentiation in the optimized vacancy-engineered NFO resistive switches, ideal for solid-state synapses achieved in a single system. Our work on correlated oxide forming-free resistive switches holds significant potential for CMOS-compatible low-power, nonvolatile resistive memory and neuromorphic circuits.

Bone strength is an important contributor to fracture risk. Areal bone mineral density (aBMD) derived from dual-energy X-ray absorptiometry (DXA) is used as a surrogate for bone strength in fracture risk prediction tools. 3D finite element (FE) models predict bone strength better than aBMD, but their clinical use is limited by the need for 3D computed tomography and lack of automation. We have earlier developed amethod to reconstruct the 3D hip anatomy froma 2D DXA image, followed by subject-specific FE-based prediction of proximal femoral strength. In the current study, we aim to evaluate the method's ability to predict incident hip fractures in a populationbased cohort (Osteoporotic Fractures in Men [MrOS] Sweden). We defined two subcohorts: (i) hip fracture cases and controls cohort: 120men with a hip fracture (<10 years frombaseline) and two controls to each hip fracture case, matched by age, height, and body mass index; and (ii) fallers cohort: 86men who had fallen the year before their hip DXA scan was acquired, 15 of which sustained a hip fracture during the following 10 years. For each participant, we reconstructed the 3D hip anatomy and predicted proximal femoral strength in 10 sideways fall configurations using FE analysis. The FE-predicted proximal femoral strength was a better predictor of incident hip fractures than aBMD for both hip fracture cases and controls (difference in area under the receiver operating characteristics curve, Delta AUROC = 0.06) and fallers (Delta AUROC = 0.22) cohorts. This is the first time that FE models outperformed aBMD in predicting incident hip fractures in a population-based prospectively followed cohort based on 3D FE models obtained from a 2D DXA scan. Our approach has potential to notably improve the accuracy of fracture risk predictions in a clinically feasible manner (only one single DXA image is needed) and without additional costs compared to the current clinical approach.

Many enzymes use adaptive frameworks to preorganize substrates,accommodate various structural and electronic demands of intermediates,and accelerate related catalysis. Inspired by biological systems,a Ru-based molecular water oxidation catalyst containing a configurationallylabile ligand [2,2 ':6 ',2 ''-terpyridine]-6,6 ''-disulfonatewas designed to mimic enzymatic framework, in which the sulfonatecoordination is highly flexible and functions as both an electrondonor to stabilize high-valent Ru and a proton acceptor to acceleratewater dissociation, thus boosting the catalytic water oxidation performancethermodynamically and kinetically. The combination of single-crystalX-ray analysis, various temperature NMR, electrochemical techniques,and DFT calculations was utilized to investigate the fundamental roleof the self-adaptive ligand, demonstrating that the on-demand configurationalchanges give rise to fast catalytic kinetics with a turnover frequency(TOF) over 2000 s(-1), which is compared to oxygen-evolvingcomplex (OEC) in natural photosynthesis.

One novel option for treating metastatic castration resistant prostate cancer is radionuclide therapy targeting prostate-specific membrane antigen (PSMA), e.g. [Lu-177]Lu-PSMA-617. Overexpression of HER2 has been found in 80% of metastatic cases of prostate cancer. Previous research showed that HER2 is elevated post irradiation in PC-3 prostate cancer cells. Co-treating with anti-HER2 antibody Trastuzumab gave less proliferation of irradiated tumor cells in vitro, and when using radionuclide therapy, also in vivo. The aim of this study is to determine whether the same holds true in PSMA-expressing PC-3 PIP cells using [Lu-177]Lu-PSMA-617 radionuclide therapy. PC-3 PIP and 22Rv1 prostate cancer cells were tested in vitro, treated with 6 Gy of x-rays with or without Trastuzumab incubation. We measured uptake of HER2-targeting affibody [Ga-68]Ga-ABY-025 and cell survival, e.g. using the WST-1 assay. Three groups (n=10 each) of male nude Balb/c mice were inoculated with PC-3 PIP xenograft tumors and treated with just [Lu-177]Lu-PSMA-617 (20 MBq), [Lu-177]Lu-PSMA-617 (20 MBq) and Trastuzumab (4 x 5 mg/kg), or left untreated. Tumor sizes and animal survival was observed. In vitro, x-ray irradiation did reduce survival in 22Rv1 but not PC-3 PIP cells, and there was no significant effect of Trastuzumab treatment. Cells expressed HER2 but not significantly elevated post irradiation. In vivo, mice co-treated with Trastuzumab had significantly longer survival than untreated mice, but not than only [Lu-177]Lu-PSMA-617. Staining of tumor sections showed similar HER2 and PSMA expression across groups. In conclusion, these results give no support for any benefit from co-treatment with anti-HER2 antibody for PSMA-targeted radioligand therapy.

Metal centers in transition metal–ligand complexes occur in a variety of oxidation states causing their redox activity and therefore making them relevant for applications in physics and chemistry. The electronic state of these complexes can be studied by X-ray absorption spectroscopy, which is, however, due to the complex spectral signature not always straightforward. Here, we study the electronic structure of gas-phase cationic manganese acetylacetonate complexes Mn(acac)_1–3⁺ using X-ray absorption spectroscopy at the metal center and ligand constituents. The spectra are well reproduced by multiconfigurational wave function theory, time-dependent density functional theory as well as parameterized crystal field and charge transfer multiplet simulations. This enables us to get detailed insights into the electronic structure of ground-state Mn(acac)_1–3⁺ and extract empirical parameters such as crystal field strength and exchange coupling from X-ray excitation at both the metal and ligand sites. By comparison to X-ray absorption spectra of neutral, solvated Mn(acac)_2,3 complexes, we also show that the effect of coordination on the L₃ excitation energy, routinely used to identify oxidation states, can contribute about 40–50% to the observed shift, which for the current study is 1.9 eV per oxidation state.

Most of the physical, mechanical, and esthetic properties of wood products are affected by the drying of sawn timber. A better understanding of moisture transport in wood during kiln drying is necessary to obtain better quality products, shorter drying schedules, lower energy consumption, and a more sustainable process. Four-dimensional X-ray computed tomography (4DCT) (three-dimensional in space and one in time) with image processing techniques can be used to study the moisture content (MC) of sawn timber during kiln drying. The development of the technique is however made difficult by computational complexity and a lack of accurate experimental validation. In this study, a method relying on 4DCT has been developed using state-of-the-art image processing techniques. The method was validated by a regression analysis of the predicted MC against gravimetric measurements for different timber cross sections and differentinitial MC distributions on a significantly smaller scale than has previously been investigated. It is concluded that the MC can be estimated with an average uncertainty of ±4.8 percentage points on a 10 mm scale. Sawmills could ultimately benefit from a better understanding of wood-water interactions and dry sawn timber more efficiently.

One of the reasons for the high efficiency and selectivity of biological catalysts arise from their ability to control the pathways of substrates and products using protein channels, and by modulating the transport in the channels using the interaction with the protein residues and the water/hydrogen-bonding network. This process is clearly demonstrated in Photosystem II (PS II), where its light-driven water oxidation reaction catalyzed by the Mn4CaO5 cluster occurs deep inside the protein complex and thus requires the transport of two water molecules to and four protons from the metal center to the bulk water. Based on the recent advances in structural studies of PS II from X-ray crystallography and cryo-electron microscopy, in this review we compare the channels that have been proposed to facilitate this mass transport in cyanobacteria, red and green algae, diatoms, and higher plants. The three major channels (O1, O4, and Cl1 channels) are present in all species investigated; however, some differences exist in the reported structures that arise from the different composition and arrangement of membrane extrinsic subunits between the species. Among the three channels, the Cl1 channel, including the proton gate, is the most conserved among all photosynthetic species. We also found at least one branch for the O1 channel in all organisms, extending all the way from Ca/O1 via the ‘water wheel’ to the lumen. However, the extending path after the water wheel varies between most species. The O4 channel is, like the Cl1 channel, highly conserved among all species while having different orientations at the end of the path near the bulk. The comparison suggests that the previously proposed functionality of the channels in T. vestitus (Ibrahim et al., Proc Natl Acad Sci USA 117:12624-12635, 2020; Hussein et al., Nat Commun 12:6531, 2021) is conserved through the species, i.e. the O1-like channel is used for substrate water intake, and the tighter Cl1 and O4 channels for proton release. The comparison does not eliminate the potential role of O4 channel as a water intake channel. However, the highly ordered hydrogen-bonded water wire connected to the Mn4CaO5 cluster via the O4 may strongly suggest that it functions in proton release, especially during the S-0 -> S-1 transition (Saito et al., Nat Commun 6:8488, 2015; Kern et al., Nature 563:421-425, 2018; Ibrahim et al., Proc Natl Acad Sci USA 117:12624-12635, 2020; Sakashita et al., Phys Chem Chem Phys 22:15831-15841, 2020; Hussein et al., Nat Commun 12:6531, 2021).

This project investigates how different types of perovskite solar cells, differentiated by choice of materials and processing techniques, compares to each other regarding performance and characterization. The purpose of the project is to further develop perovskite solar cells and to improve the method of manufacturing for better performance.

A total of 160 perovskite solar cells are constructed, divided into eight distinct types. Two different perovskites, MAPbI₃ and MAFAPbI₃, are used and prepared using two different solvents: isopropanol (IPA) and pentanol (PenOH). Furthermore half of the solar cells contain phenethylammonium iodide (PEAI). When completed, the solar cells' performances are measured and compared. Lastly, the solar cells and the perovskites are compared through characterization measurements. An incident-photon-to-current-efficiency (IPCE) spectroscopy is performed on the solar cells to get a better understanding of the efficiency depending on the wavelength of the incident light. An UV-vis-NIR spectroscopy is performed on the thin film to analyze the absorbance and determine the band gap of the material. The pre-crystallized perovskite powders are compared through characterization measurements, such as X-ray Photoelectron Spectroscopy (XPS) characterization and scanning electron microscopy (SEM) measurements. This results in comparing material compositions and optical properties of the solar cells.

The results indicate that MAPbI₃ (PenOH) is the highest performing type independent of the presence of PEAI. The measured mean power conversion efficiency (PCE) are 15.47% and 13.84% for MAPbI₃ (PenOH) with and without PEAI respectively. The best performing individual solar cell contains MAPbI₃ (PenOH) with PEAI and has a PCE of 20.21%. On the contrary, MAFAPbI₃ (PenOH) with and without PEAI perform the worst. The best improvement of the PCE after two weeks is +22.13%, given by MAPbI₃ (PenOH) with PEAI. Generally, solar cells with MAPbI₃ have a larger band gap, 1.61 eV, compared to MAFAPbI₃'s 1.55 eV, regardless of the presence of PEAI. MAPbI₃ (PenOH) can convert a larger portion of incident photons to electrical energy, up to almost 80%. MAFAPbI₃ (IPA) converts almost as much, over 70%, while MAPbI₃ (IPA) and MAFAPbI₃ (PenOH) in some measurements barely has a 50% conversion rate.

Photochemistry and photophysics processes involve structures far from equilibrium. In these reactions, there is often strong coupling between nuclear and electronic degrees of freedom. For first-row transition metals, K beta X-ray emission spectroscopy (XES) is a sensitive probe of electronic structure due to the direct overlap between the valence orbitals and the 3p hole in the final state. Here the sensitivity of K beta mainline (K beta(1,3)) XES to structural dynamics is analyzed by simulating spectral changes along the excited state dynamics of an iron photosensitizer [Fe-II(bmip)(2)](2+) [bmip = 2,6-bis(3-methyl-imidazole-1-ylidine)-pyridine], using both restricted active space (RAS) multiconfigurational wavefunction theory and a one-electron orbital-energy approach in density-functional theory (1-DFT). Both methods predict a spectral blue-shift with increasing metal-ligand distance, which changes the emission intensity for any given detection energy. These results support the suggestion that the [Fe-II(bmip)(2)](2+) femtosecond K beta XES signal shows oscillations due to coherent wavepacket dynamics. Based on the RAS results, the sensitivity to structural dynamics is twice as high for K beta compared to K alpha, with the drawback of a lower signal-to-noise ratio. K beta sensitivity is favored by a larger spectral blue-shift with increasing metal-ligand distance and larger changes in spectral shape. Comparing the two simulations methods, 1-DFT predicts smaller energy shifts and lower sensitivity, likely due to missing final-state effects. The simulations can be used to design and interpret XES probes of non-equilibrium structures to gain mechanistic insights in photocatalysis.

Laboratory column experiments have been used to study the sequential removal of nitrate (NO₃⁻) and sulfate (SO₄²⁻) from mine water, where NO₃⁻ was removed through denitrification and SO₄²⁻ was removed through SO₄²⁻ reduction and the subsequent precipitation of hydrogen sulfide (H₂S) in a hematite-coated biochar (HCB) bioreactor. Denitrification and SO₄²⁻ reduction were investigated in columns filled with pine woodchips and pine woodchips + biochar, both with and without the addition of lactate. Experimental results indicated that a >90% NO₃⁻ removal from 50 mg L⁻¹ NO₃⁻-N was achieved at a hydraulic residence time of 5 days without lactate addition, but that SO₄²⁻ reduction was minimal after an initial startup period. Lactate was added to stimulate SO₄²⁻ reduction, producing H₂S with >90% SO₄²⁻ removal from an initial concentration of 361 mg L⁻¹ SO₄²⁻-S. Sulfate concentrations were reduced to a greater extent in the woodchip + biochar column, and NH₄⁺ production was enhanced in both columns after lactate addition. After treatment in the HCB columns, H₂S and NH₄⁺ were removed to >95%. X-ray photoelectron spectroscopy (XPS) indicated that S²⁻, S₂²⁻, S⁰ and NH₄⁺ were accumulating in the HCB columns and surface-bound iron was converted from Fe(III) to Fe(II). The XPS results suggested that the reductive dissolution of hematite preceded the precipitation of H₂S as FeS, pyrite and elemental sulfur on the HCB surfaces.

The solvation capacity of dispersion solvents plays a crucial role in the solution processing of metal halide perovskites. For instance, N,N-dimethylformamide (DMF), a widely used dispersion solvent, possesses high solvation capacity but often generates suboptimal film quality due to slow crystallization kinetics. We propose using low-solvation binary cosolvents (nitrile-and ether-type solvents) to achieve a balance between solvation (i.e., sufficient solubility of precursors) and desolvation (i.e., rapid crystallization of films) pro-cesses during perovskite synthesis. The polarity and hydrogen -bonding property of these cosolvents synergistically enhance their solvation capacity, facilitating perovskite precursor dissolution. Moreover, the low-solvation cosolvents accelerate the crystalliza-tion of well-defined intermediate films, yielding higher-quality pe-rovskites than those synthesized with DMF. The optimized modules achieved an active-area efficiency of 22.27%, with a certified aper-ture-area efficiency of 16.10% and corresponding active-area effi-ciency of 20.75%. This research on solvation regulation provides universal guidelines for innovatively preparing high-quality halide perovskites.

Previously unknown Co-2(TeO3)(OH)(2) and Co-15(TeO3)(14)(OH)(2) were obtained under mild hydrothermal reaction conditions (210 degrees C, autogenous pressure) from alkaline solutions. Their crystal structures were determined from single-crystal X-ray diffraction data. Co-2(TeO3)(OH)(2) (Z = 2, P1 over bar , a = 5.8898(5), b = 5.9508(5), c = 6.8168(5) & ANGS;, alpha = 101.539(2), beta = 100.036(2), gamma = 104.347(2)& DEG;, 2120 independent reflections, 79 parameters, R[F-2 > 2 sigma(F-2)] = 0.017) crystallizes in a unique structure comprised of undulating (2)(& PROP;)[Co-2(OH)(6/3)O3/3O2/2O1/1](4-) layers. Adjacent layers are linked by Te-IV atoms along the [001] stacking direction. Co-2(TeO3)(OH)(2) is stable up to 450 & DEG;C and decomposes under the release of water into Co6Te5O16 and CoO. Magnetic measurements of Co-2(TeO3)(OH)(2) showed antiferromagnetic ordering at & AP; 70 K. The crystal structure of Co-15(TeO3)(14)(OH)(2) (Z = 3, R3 over bar , a = 11.6453(2), c = 27.3540(5) & ANGS;, 3476 independent reflections, 112 parameters, R[F-2 > 2 sigma(F-2)] = 0.026) is isotypic with Co-15(TeO3)(14)F-2. A quantitative structural comparison revealed that the main structural difference between the two phases is connected with the replacement of F by OH, whereas the remaining part of the three-periodic network defined by [CoO6], [CoO5(OH)], [CoO5] and [TeO3] polyhedra is nearly unaffected. Consequently, the magnetic properties of the two phases are similar, namely being antiferromagnetic at low temperatures.

The Concise Guide to PHARMACOLOGY 2023/24 is the sixth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of approximately 1800 drug targets, and about 6000 interactions with about 3900 ligands. There is an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes almost 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at . G protein-coupled receptors are one of the six major pharmacological targets into which the Guide is divided, with the others being: ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2023, and supersedes data presented in the 2021/22, 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate.

We designed and investigated the electronic, mechanical, and thermoelectric properties of Graphene/hexagonal Boron Nitride (Gr/h-BN) heterostructure at various twisting angles based on the Ab-initio simulation. The structural stability was studied at optimized rotation angles (cp) = 0 degrees, 16.10 degrees, 21.79 degrees, 38.21 degrees, 43.90 degrees and 60 degrees. The heterostructure shows semiconducting nature at cp = 0 degrees, 21.79 degrees and 38.21 degrees. These twisted heterostructures have demonstrated extraordinary mechanical properties such as Young's modulus and bulk modulus. Using the semiclassical Boltzmann transport theory, it is observed that the Seebeck coefficient, electric conductivity, and power factor at cp = 0 degrees, 21.79 degrees, 38.21 degrees, and 60 degrees are much higher than the values measured at cp = 16.10 degrees and 43.90 degrees. Moreover, at cp = 60 degrees, the Power Factor for the n-type dopants can reach 1.37 x 1011 W/msK2. The lattice thermal conductivity at room temperature is found to be very low for cp = 16.10 degrees, 21.79 degrees, 43.90 degrees and 38.21 degrees rotation angles. An ultralow lattice thermal conductivity with a value of 0.095 W/mK at 300K has been observed for 21.79 degrees rotation angle, which is lower than other rotation angles because of very low group velocity (22.1 km/s) and short phonon lifetime (similar to 0.12 ps). The high thermoelectric performance results from an ultralow thermal conductivity arising due to the strong lattice anharmonicity. The present observations can offer significant impact on the design of high performance thermoelectric materials based on twisted van der Waals heterostructure (vdWH).

INTRODUCTION 

One of the main limiting factors to the life span of spinal implants is the release of detrimental ions and particles, which are typically produced by wear and corrosion1,2. One suggested approach to overcome these issues is the use of silicon nitride-based coatings on metallic implants because of their low wear rates and their ability to slowly dissolve in aqueous solutions into biocompatible ions only, which could be advantageous in terms of limiting the effects of wear debris and ion release3. A previous study found that alloying the silicon nitride coating with Fe and C did not have a negative effect on mechanical properties nor biocompatibility in a direct contact in vitro test4. However, the dissolution behaviour of the coatings remains to be investigated. Furthermore, due to the close proximity to nerve tissues in spinal implants, the effect of the ions released on the neural tissue is a concern. The present study aimed to study the dissolution behaviour and in vitro neural cell response of SiFeCN coatings. A combinatorial approach was used for efficient screening of different compositions. 

EXPERIMENTAL METHODS 

SiFeCN coatings were deposited on CoCr disc substrates by reactive sputtering in an in-house built equipment, allowing for combinatorial processes, using Si, Fe and C solid targets. Nitrogen was supplied as a reactive gas. The coatings were characterized in 9 points using x-ray photoelectron spectroscopy (XPS), vertical scanning interferometry (VSI) and scanning electron microscopy (SEM). The points were placed in a 3x3 grid with 22.5 mm between each point. 

The dissolution behaviour was evaluated by exposing the coated samples to cell media for 14 days. The obtained extracts were diluted (1:32, 1:48, 1:64 and 1:80 dilution) and used to measure ion levels with inductively coupled plasma (ICP-OES) and to assess indirect biocompatibility in vitro using the MTT assay and glial cells. 

RESULTS AND DISCUSSION 

The XPS results showed compositional gradients of Si ranging between 36.4-47.3 at.%, Fe 1.4-9.3 at.% and C 4.5-13.9 at.% with average surface roughness, Sa, of 7.4 to 11.1 nm, similar to SiN and CoCr reference materials. SEM after exposure displayed signs of dissolution with visibly increased porosity for the coated samples. The SiN reference also showed substantial changes to the surface. The ICP results (Figure 1) showed a reduction in Co ions from the substrate in the coated samples compared to uncoated. Moreover, the addition of Fe and C decreased the ion release from the coating compared to the SiN reference coating. Extract biocompatibility tests suggested that glial cells tolerated the extracts and their dilutions obtained from the coated samples in a dose- dependent manner and the cell viability was comparable to that of the uncoated CoCr and SiN coating. 

CONCLUSIONS 

The findings from this study suggest that using iron and carbon as alloying elements in silicon nitride coatings has the potential to reduce ion release from a metallic substrate and lower the dissolution rate of the coating, while having a comparable cell response to that of the CoCr and SiN control materials. Therefore, SiFeCN coatings merit further investigation as a future option for spinal implants. 

REFERENCES 

1.Shimamura Y. et al., Spine. 33(4):351–355, 2008 2.Vicars R. et al., Comprehensive Biomaterials II. (pp. 246–264), 20173. Pettersson M. et al., ACS Biomaterials Science and Engineering. 2(6):998–1004, 20164. Skjöldebrand C. et al., Materials (Basel). 13(9):1–16, 2020 

ACKNOWLEDGMENTS 

This project has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 812765 and from the European Union’s Seventh Framework Programme (FP7/2007-2013), grant agreement GA-310477(LifeLongJoints). 

A series of heteroleptic Cu(I) diimine complexes with different ancillary ligands and 6,6'-dimethyl-2,2'-bipyridine-4,4'-dibenzoic acid (dbda) as the anchoring ligand were selfassembled on TiO2 surfaces and used as dyes for dye-sensitized solar cells (DSSCs). The binding to the TiO2 surface was studied by hard X-ray photoelectron spectroscopy for a brominecontaining complex, confirming the complex formation. The performance of all complexes was assessed and rationalized on the basis of their respective ancillary ligand. The DSSC photocurrent-voltage characteristics, incident photon-to-current conversion efficiency (IPCE) spectra, and calculated lowest unoccupied molecular orbital (LUMO) distributions collectively show a push-pull structural dye design, in which the ancillary ligand exhibits an electron-donating effect that can lead to improved solar cell performance. By analyzing the optical properties of the dyes and their solar cell performance, we can conclude that the presence of ancillary ligands with bulky substituents protects the Cu(I) metal center from solvent coordination constituting a critical factor in the design of efficient Cu(I)-based dyes. Moreover, we have identified some components in the I-/I-3(-)-based electrolyte that causes dissociation of the ancillary ligand, i.e., TiO2 photoelectrode bleaching. Finally, the detailed studies on one of the dyes revealed an electrolyte-dye interaction, leading to a dramatic change of the dye properties when adsorbed on the TiO2 surface.

A novel tetratopic metallo-linker, [Ru(tda)(py(PhCOOH)2)2], 1, (tda = 2,2′:6′,2′′-terpyridine-6,6′′-dicarboxylate; py(PhCOOH)2 = (4,4′-(pyridine-3,5-diyl)dibenzoic acid), that is structurally based on one of the most active molecular water oxidation catalysts has been prepared and fully characterized, including single crystal X-ray diffraction. 1 bears geometric similarities to H4TBAPy (H4TBAPy = 4,4′,4′′,4′′′-(pyrene-1,3,6,8-tetrayl)tetrabenzoic acid), i.e. the native linker in NU-1000, which offers the possibility to synthesize NU-1000-Ru mixed linker MOFs solvothermally. Mixed linker MOF formation was demonstrated by powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM), and Ru linker incorporation confirmed by FT-IR, energy-dispersive X-ray (EDX) spectroscopy and inductively coupled plasma optical emission spectroscopy (ICP-OES). It was found that the Ru contents in the final mixed linker MOFs correlate with the amount of Ru linker present during solvothermal synthesis, albeit not in a linear fashion. The cyclic voltammograms (CV) of the mixed linker MOFs are largely dominated by TBAPy-based oxidations with features attributed to 1. Interestingly, Ru linkers near the crystal surface are oxidized directly by interfacial hole transfer form the electrode, while those in the crystal interior can be oxidized indirectly from oxidized TBAPy linkers at more anodic potential. Upon repeated scanning, the CVs show the appearance of new waves that arise from irreversible TBAPy oxidation, as well as from the activation of the Ru-based water oxidation catalyst. Of the materials prepared, the one with the highest Ru content, NU-1000-Ruhigh, was shown to catalyze the electrochemical oxidation of water to dioxygen. The Faradaic efficiency (FE) of the construct is 37%, due to water oxidation being accompanied by oxidative transformations of the TBAPy linkers. Despite the low FE, NU-1000-Ruhigh is still among the best MOF-based water oxidation catalysts, operating by a unique co-linker mediated hole-transport mechanism to supply oxidizing equivalents also to catalysts in the crystal interior.

This study demonstrates the electrochemical sodiation and desodiation of gallium (Ga). A variety of techniques including galvanostatic cycling, cyclic voltammetry, as well as ex situ and in situ powder X-ray diffraction were used to determine the electrochemical reaction mechanisms. The sodiation and desodiation of Ga occurs reversibly at 0.71 V vs Na+/Na and the sodiated product was determined to be NaGa4 with a theoretical capacity of 96 mAh g(-1) (567 mAh cm(-3)). In addition, an anomalous plateau was observed at 0.66 V vs Na+/Na during the sodiation, which was attributed to a slow diffusion of Na into Ga particles. It was also shown that Na22Ga39 was not formed even if it is one of the expected compounds from the Ga-Na phases diagram. However, new crystalline structures were observed and were attributed to metastable phases of NaGa4.

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy's active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of 79(-20)(+22) neutrinos at tera-electron volt energies, with a global significance of 4.2 sigma, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera-electron volt gamma rays from this source.

Experimental near-edge x-ray-absorption fine-structure (NEXAFS) spectra of the nitrosonium NO+ ion are presented and theoretically analyzed. While neutral NO has an open shell, the cation is a closed-shell species, which for NEXAFS leads to the simplicity of a closed-shell spectrum. Compared to neutral NO, the electrons in the cation experience a stronger Coulomb potential, which introduces a shift of the ionization potential towards higher energies, a depletion of intensity in a large interval above the pi* resonance, and a shift of the sigma* resonance from the continuum to below the ionization threshold. NEXAFS features at the nitrogen and oxygen K edges of NO+ are compared, as well as NEXAFS features at the nitrogen edges of the isoelectronic closed-shell species NO+, N2, and N2H+.

The influence of changes induced by ion irradiation on structure and thermal stability of metastable cubic (Ti,Al)N coatings deposited by cathodic arc evaporation is systematically investigated by correlating experiments and theory. Decreasing the nitrogen deposition pressure from 5.0 to 0.5 Pa results in an ion flux-enhancement by a factor of three and an increase of the average ion energy from 15 to 30 eV, causing the stress-free lattice parameter to expand from 4.170 to 4.206 Å, while the chemical composition of Ti_0.27Al_0.21N_0.52 remains unchanged. The 0.9% lattice parameter increase is a consequence of formation of Frenkel pairs induced by ion bombardment, as revealed by density functional theory (DFT) simulations. The influence of the presence of Frenkel pairs on the thermal stability of metastable Ti_0.27Al_0.21N_0.52 is investigated by scanning transmission electron microscopy, differential scanning calorimetry, atom probe tomography and in-situ synchrotron X-ray powder diffraction. It is demonstrated that the ion flux and ion energy induced formation of Frenkel pairs increases the thermal stability as the Al diffusion enabled crystallization of the wurtzite solid solution is retarded. This can be rationalized by DFT predictions since the presence of Frenkel pairs increases the activation energy for Al diffusion by up to 142%. Hence, the thermal stability enhancement is caused by a hitherto unreported mechanism - the Frenkel pair impeded Al mobility and thereby retarded formation of wurtzite solid solution.

Sustainable sources of hydrogen are a vital component of the envisioned energy transition. Understanding and mimicking the [FeFe]-hydrogenase provides a route to achieving this goal. In this study we re-visit a molecular mimic of the hydrogenase, the propyl dithiolate bridged complex [Fe₂(μ-pdt)(CO)₄(CN)₂]²⁻, in which the cyanide ligands are tuned via Lewis acid interactions. This system provides a rare example of a cyanide containing [FeFe]-hydrogenase mimic capable of catalytic proton reduction, as demonstrated by cyclic voltammetry. EPR, FTIR, UV-vis and X-ray absorption spectroscopy are employed to characterize the species produced by protonation, and reduction or oxidation of the complex. The results reveal that biologically relevant iron-oxidation states can be generated, potentially including short-lived mixed valent Fe(I)Fe(II) species. We propose that catalysis is initiated by protonation of the diiron complex and the resulting di-ferrous bridging hydride species can subsequently follow two different pathways to promote H₂ gas formation depending on the applied reduction potential.

Full understanding of moisture transport in wood is not achieved despite many transport theories (Thybring et al. 2021). It remains an essential research domain to improve both timber quality and drying schedules. X-ray Computed Tomography (CT) has shown to be a useful tool in this regard as it allows for the computation of moisture-content (MC) at voxel level (Couceiro 2019). To the knowledge of the authors, no method exists to analyse the evolution of MC and gradient (MG) distributions, that can later be related to the quality of the sawn-timber. Popular methods, such as presented in Esping 1988, to quantify the MG are not adapted to CT (local) data as they provide averaged (global) MC and MG. In this study, an analysis method based on image-processing and CT data is presented to statistically quantify the evolution of MC and MG distributions within cross-sections of timber during drying.

The electrolyte solution of NaBOB in TEP is a low-cost, fluorine-free and flame-retardant electrolyte with ionic conductivity of 5 mS cm(-1), recently discovered to show promises for sodium-ion batteries. Here, the abilities of this electrolyte to effectively form a solid electrolyte interphase (SEI) was augmented with five common electrolyte additives of fluoroethylene carbonate (FEC), vinylene carbonate (VC), prop-1-ene-1,3-sultone (PES), 1,3,2-dioxathiolane 2,2-dioxide (DTD) and tris(trimethylsilyl)phosphite (TTSPi). Full-cells with electrodes of Prussian white and hard carbon and industrial mass loadings of >10 mg cm(-2) and electrolyte volumes of <5 ml g(-1) were used. X-ray photoelectron spectroscopy (XPS) and pressure analysis were also deployed to investigate parasitic reactions. Cells using electrolyte additives of PES, PES+DTD and PES+TTSPi (3 wt%) showed significantly increased performance in terms of capacity retention and initial Coulombic efficiency as compared to additive-free NaBOB-TEP. The best cell retained 80% discharge capacity (89 mAh g(-1)) after 450 cycles, which is also significantly better than reference cells using 1 M NaPF6 in EC:DEC electrolyte. This study sheds light on opportunities to optimize the NaBOB-TEP electrolyte for full-cell sodium-ion batteries in order to move from low-mass-loading lab-scale electrodes to high mass loading electrodes aiming for commercialization of sodium-ion batteries.

Postcollision-interaction (PCI) effects involving multistep decay processes following Ar 1s photoionization has been studied by Auger electron spectroscopy. The experiment focused on LMM Auger electrons measured in small photon energy steps across the Ar 1s photoionization threshold. Decay pathways that we studied include (1) the Ar+*2p-1 -> Ar2+3p-2 LMM alpha Auger process due to a single L hole created by KL fluorescence, (2) the Ar2+*2p-2 -> Ar3+*2p-13p-2 LMM1 Auger process following double L shell hole states produced by a KLL Auger processes, and (3) the subsequent Ar3+*2p-13p-2 -> Ar4+3p-4 LMM2 Auger transitions. Particularly pronounced PCI shifts and unusual line shapes compared to the ordinary one-step PCI process were found in the spectra of Auger processes following a KLL Auger first step. The experimental results were compared with calculations based on the semiclassical approach to PCI. Good agreement was found between the calculated and experimental PCI shifts. The result opens possibilities for further studies of the multielectron dynamics between Auger electrons mediated through the photoelectron in these and similar systems.

PANDA (anti-proton annihiliation at Darmstadt) is planned to be one of the four main experiments at the future international accelerator complex FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. It is going to address fundamental questions of hadron physics and quantum chromodynamics using cooled antiproton beams with a high intensity and and momenta between 1.5 and 15 GeV/c. PANDA is designed to reach a maximum luminosity of 2 × 10³² cm⁻² s. Most of the physics programs require an excellent particle identification (PID). The PID of hadronic states at the forward endcap of the target spectrometer will be done by a fast and compact Cherenkov detector that uses the detection of internally reflected Cherenkov light (DIRC) principle. It is designed to cover the polar angle range from 5° to 22° and to provide a separation power for the separation of charged pions and kaons up to 3 standard deviations (s.d.) for particle momenta up to 4 GeV/c in order to cover the important particle phase space. This document describes the technical design and the expected performance of the novel PANDA disc DIRC detector that has not been used in any other high energy physics experiment before. The performance has been studied with Monte-Carlo simulations and various beam tests at DESY and CERN. The final design meets all PANDA requirements and guarantees sufficient safety margins.

On 22 September 2017, IceCube reported a high-energy neutrino event which was found to be coincident with a flaring blazar, TXS 0506+056. This multi-messenger observation hinted at blazars contributing to the observed high-energy astrophysical neutrinos and raised a need for extensive correlation studies. Recent work shows that the internal absorption of gamma rays, and their interactions intrinsic to the source and with the extragalactic background, will cause a lack of energetic gamma-ray and neutrino correlation while hinting towards a correlation between neutrinos and lower photon energy observations in the X-ray and radio bands. Studies based on published IceCube alerts and radio observations report a possible radio-neutrino correlation in both gamma-ray bright and gamma-ray dim active galactic nuclei (AGN). However, they have marginal statistical significance due to limited available data. We present a correlation analysis between 15 GHz radio observations of AGN reported in the MOJAVE XV catalog and 10 years of IceCube detector data and discuss the results derived from a time-averaged stacking analysis.