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Covalent 2D magnets such as Cr 2 Te 3 , which feature self-intercalated magnetic cations located between monolayers of transition-metal dichalcogenide material, offer a unique platform for controlling magnetic order and spin texture, enabling new potential applications for spintronic devices. Here, it is demonstrated that the unconventional anomalous Hall effect (AHE) in Cr 2 Te 3 , characterized by additional humps and dips near the coercive field in AHE hysteresis, originates from an intrinsic mechanism dictated by the self-intercalation. This mechanism is distinctly different from previously proposed mechanisms such as topological Hall effect, or two-channel AHE arising from spatial inhomogeneities. Crucially, multiple Weyl-like nodes emerge in the electronic band structure due to strong spin-orbit coupling, whose positions relative to the Fermi level is sensitively modulated by the canting angles of the self-intercalated Cr cations. These nodes contribute strongly to the Berry curvature and AHE conductivity. This component competes with the contribution from bands that are less affected by the self-intercalation, resulting in a sign change in AHE with temperature and the emergence of additional humps and dips. The findings provide compelling evidence for the intrinsic origin of the unconventional AHE in Cr 2 Te 3  and further establish self-intercalation as a control knob for engineering AHE in complex magnets., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Background: Little is known about the protein expression of the transient receptor potential canonical (TRPC) channels 1, 3, and 6 in the thyroid. Research in human tissue is insufficient. Our aim was to investigate the distribution of TRPC1, 3, and 6 in the healthy human thyroid., Methods: Healthy samples were collected from seven nitrite pickling salt-ethanol-polyethylene glycol-fixed cadavers and from one patient who had undergone neck surgery (5 males, 3 females; median = 81.0, interquartile range = 6.5 years). The protein expression profiles of TRPC1, 3, and 6 were assessed using immunohistochemistry with knockout-validated antibodies. A monoclonal calcitonin antibody was used to detect calcitonin-producing C-cells., Results: All samples were labeled as healthy, displaying age-appropriate signs of degeneration. TRPC1, 3, and 6 immunolabeling in thyrocytes showed irregular staining patterns leaving selected cells with intense staining, some without. The comparison of calcitonin- and TRPC1-, 3-, and 6-immunolabeled slides strongly suggested TRPC1, 3, and 6 expression in C-cells. Connective tissue showed no immunoreactivity., Conclusions: This is, to the authors' knowledge, the first detailed description of the distribution of these channels in the human thyroid. We conclude that TRPC1, 3, and 6 are expressed in thyrocytes and C-cells of the human thyroid. Further studies are necessary to confirm these small-case-number results and to explore the relevance of these versatile channels in thyroidal health and disease., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Background: Expression and function of TRPC3 and TRPC6 in the pancreas is a controversial topic. Investigation in human tissue is seldom. We aimed to provide here a detailed description of the distribution of TRPC3 and TRPC6 in the human exocrine and endocrine pancreas., Methods: We collected healthy samples from cadavers (n = 4) and visceral surgery (n = 4) to investigate the respective expression profiles using immunohistochemical tracing with knockout-validated antibodies., Results: TRPC3- and TRPC6-proteins were detected in different pancreatic structures including acinar cells, as well as epithelial ductal cells from intercalate, intralobular, and interlobular ducts. Respective connective tissue layers appeared unstained. Endocrine islets of Langerhans were clearly and homogenously immunolabeled by the anti-TRPC3 and anti-TRPC6 antibodies. Insular α, β, γ, and δ cells were conclusively stained, although no secure differentiation of cell types was performed., Conclusions: Due to aforementioned antibody specificity verification, protein expression in the immunolabeled localizations can be accepted. Our study in human tissue supports previous investigations especially with respect to acinar and insular α and β cells, while other localizations are here reported for the first time to express TRPC3 and TRPC6, ultimately warranting further research., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Quantum technologic and spintronic applications require reliable material platforms that enable significant and long-living spin polarization of excitations, the ability to manipulate it optically in external fields, and the possibility to implement quantum correlations between spins, i.e., entanglement. Here it is demonstrated that these conditions are met in bulk crystals of lead halide perovskites. A giant optical orientation of 85% of excitons, approaching the ultimate limit of unity, in FA 0.9 Cs 0.1 PbI 2.8 Br 0.2 crystals is reported. The exciton spin orientation is maintained during the exciton lifetime of 55 ps resulting in high circular polarization of the exciton emission. The optical orientation is robust to detuning of the excitation energy up to 0.3 eV above the exciton resonance and remains larger than 20% up to detunings of 0.9 eV. It evidences pure chiral selection rules and suppressed spin relaxation of electrons and holes, even with large kinetic energies. The exciton and electron-hole recombinations are distinguished by means of the spin dynamics detected via coherent spin quantum beats in magnetic field. Further, electron-hole spin correlations are demonstrated through linear polarization beats after circularly polarized excitation. These findings are supported by atomistic calculations. All-in-all, the results establish lead halide perovskite semiconductors as suitable platform for quantum technologies., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Transient receptor potential canonical sub-family channel 3 (TRPC3) is considered to play a critical role in calcium homeostasis. However, there are no established findings in this respect with regard to TRPC6. Although the parathyroid gland is a crucial organ in calcium household regulation, little is known about the protein distribution of TRPC channels-especially TRPC3 and TRPC6-in this organ. Our aim was therefore to investigate the protein expression profile of TRPC3 and TRPC6 in healthy and diseased human parathyroid glands. Surgery samples from patients with healthy parathyroid glands and from patients suffering from primary hyperparathyroidism (pHPT) were investigated by immunohistochemistry using knockout-validated antibodies against TRPC3 and TRPC6. A software-based analysis similar to an H-score was performed. For the first time, to our knowledge, TRPC3 and TRPC6 protein expression is described here in the parathyroid glands. It is found in both chief and oxyphilic cells. Furthermore, the TRPC3 staining score in diseased tissue (pHPT) was statistically significantly lower than that in healthy tissue. In conclusion, TRPC3 and TRPC6 proteins are expressed in the human parathyroid gland. Furthermore, there is strong evidence indicating that TRPC3 plays a role in pHPT and subsequently in parathyroid hormone secretion regulation. These findings ultimately require further research in order to not only confirm our results but also to further investigate the relevance of these channels and, in particular, that of TRPC3 in the aforementioned physiological functions and pathophysiological conditions.

The optical properties of lead halide perovskite semiconductors in vicinity of the bandgap are controlled by excitons, so that investigation of their fundamental properties is of critical importance. The exciton Landé or g-factor g X is the key parameter, determining the exciton Zeeman spin splitting in magnetic fields. The exciton, electron, and hole carrier g-factors provide information on the band structure, including its anisotropy, and the parameters contributing to the electron and hole effective masses. Here, g X is measured by reflectivity in magnetic fields up to 60 T for lead halide perovskite crystals. The materials band gap energies at a liquid helium temperature vary widely across the visible spectral range from 1.520 up to 3.213 eV in hybrid organic-inorganic and fully inorganic perovskites with different cations and halogens: FA 0.9 Cs 0.1 PbI 2.8 Br 0.2 , MAPbI 3 , FAPbBr 3 , CsPbBr 3 , and MAPb(Br 0.05 Cl 0.95 ) 3 . The exciton g-factors are found to be nearly constant, ranging from +2.3 to +2.7. Thus, the strong dependences of the electron and hole g-factors on the bandgap roughly compensate each other when combining to the exciton g-factor. The same is true for the anisotropies of the carrier g-factors, resulting in a nearly isotropic exciton g-factor. The experimental data are compared favorably with model calculation results., (© 2023 The Authors. Small published by Wiley‐VCH GmbH.)

Coherent spin dynamics of electrons and holes are studied in hybrid organic-inorganic lead halide perovskite FAPbBr 3 bulk single crystals using the time-resolved Kerr ellipticity technique at cryogenic temperatures. The Larmor spin precession of the carrier spins in a magnetic field is monitored to measure the Landé g -factors of electrons (+2.44) and holes (+0.41). These g -factors are highly isotropic. The measured spin dephasing times amount to a few nanoseconds, and the longitudinal hole spin relaxation time is 470 ns. The important role of the strong hyperfine interaction between carrier spins and nuclear spins is demonstrated via dynamic nuclear polarization. At low temperatures, electron and hole spin relaxation predominantly occurs via the hyperfine interaction, whose importance significantly decreases at temperatures above 12 K. We overview the spin dynamics in various lead halide perovskite crystals and polycrystalline films and conclude on their common features provided by charge carrier localization at cryogenic temperatures.

Coherent many-body states are highly promising for robust quantum information processing. While far-reaching theoretical predictions have been made for various implementations, direct experimental evidence of their appealing properties can be challenging. Here, we demonstrate optical manipulation of the nuclear spin ensemble in the lead halide perovskite semiconductor FAPbBr 3 (FA = formamidinium), targeting a long-postulated collective dark state that is insensitive to optical pumping after its build-up. Via optical orientation of localized hole spins we drive the nuclear many-body system into this entangled state, requiring a weak magnetic field of only a few milli-Tesla strength at cryogenic temperatures. During its fast establishment, the nuclear polarization along the optical axis remains small, while the transverse nuclear spin fluctuations are strongly reduced, corresponding to spin squeezing as evidenced by a strong violation of the generalized nuclear squeezing-inequality with ξ s  < 0.5. The dark state corresponds to an ~35-body entanglement between the nuclei. Dark nuclear spin states can be exploited to store quantum information benefiting from their long-lived many-body coherence and to perform quantum measurements with a precision beyond the standard limit., (© 2023. Springer Nature Limited.)

The tunability of the optical properties of lead halide perovskite nanocrystals makes them highly appealing for applications. Halide anion exchange and quantum confinement enable tailoring of the band gap. For spintronics, the Landé g -factors of electrons and holes are essential. Using empirical tight-binding and k · p methods, we calculate them for nanocrystals of all-inorganic lead halide perovskites CsPb X 3 ( X = I, Br, Cl). The hole g -factor band gap dependence follows the universal law found for bulk perovskites, while for electrons, a considerable modification is predicted. Based on the k · p analysis, we conclude that this difference arises from the interaction of the bottom conduction band with the spin-orbit split electron states. These predictions are confirmed experimentally for electron and hole g -factors in CsPbI 3 nanocrystals in a glass matrix, measured by time-resolved Faraday ellipticity in a magnetic field at cryogenic temperatures.

The class of Ruddlesden-Popper type (PEA) 2 PbI 4 perovskites comprises 2D structures whose optical properties are determined by excitons with a large binding energy of about 260 meV. It complements the family of other 2D semiconductor materials by having the band structure typical for lead halide perovskites, that can be considered as inverted compared to conventional III-V and II-VI semiconductors. Accordingly, novel spin phenomena can be expected for them. Spin-flip Raman scattering is used here to measure the Zeeman splitting of electrons and holes in a magnetic field up to 10 T. From the recorded data, the electron and hole Landé factors (g-factors) are evaluated, their signs are determined, and their anisotropies are measured. The electron g-factor value changes from +2.11 out-of-plane to +2.50 in-plane, while the hole g-factor ranges between -0.13 and -0.51. The spin flips of the resident carriers are arranged via their interaction with photogenerated excitons. Also the double spin-flip process, where a resident electron and a resident hole interact with the same exciton, is observed showing a cumulative Raman shift. Dynamic nuclear spin polarization induced by spin-polarized holes is detected in corresponding changes of the hole Zeeman splitting. An Overhauser field of the polarized nuclei acting on the holes as large as 0.6 T can be achieved., (© 2023 The Authors. Small published by Wiley-VCH GmbH.)

The spin physics of perovskite nanocrystals with confined electrons or holes is attracting increasing attention, both for fundamental studies and spintronic applications. Here, stable [Formula: see text] lead halide perovskite nanocrystals embedded in a fluorophosphate glass matrix are studied by time-resolved optical spectroscopy to unravel the coherent spin dynamics of holes and their interaction with nuclear spins of the 207 Pb isotope. We demonstrate the spin mode locking effect provided by the synchronization of the Larmor precession of single hole spins in each nanocrystal in the ensemble that are excited periodically by a laser in an external magnetic field. The mode locking is enhanced by nuclei-induced frequency focusing. An ensemble spin dephasing time [Formula: see text] of a nanosecond and a single hole spin coherence time of T 2  = 13 ns are measured. The developed theoretical model accounting for the mode locking and nuclear focusing for randomly oriented nanocrystals with perovskite band structure describes the experimental data very well., (© 2023. The Author(s).)

The versatile potential of lead halide perovskites and two-dimensional materials is merged in the Ruddlesden-Popper perovskites having outstanding optical properties. Here, the coherent spin dynamics in Ruddlesden-Popper (PEA) 2 PbI 4 perovskites is investigated by picosecond pump-probe Kerr rotation in an external magnetic field. The Larmor spin precession of resident electrons with a spin dephasing time of 190 ps is identified. The longitudinal spin relaxation time in weak magnetic fields measured by the spin inertia method is as long as 25 μs. A significant anisotropy of the electron g -factor with the in-plane value of +2.45 and out-of-plane value of +2.05 is found. The exciton out-of-plane g -factor of +1.6 is measured by magneto-reflectivity. This work contributes to the understanding of the spin-dependent properties of two-dimensional perovskites and their spin dynamics.

The Landé or g-factors of charge carriers are decisive for the spin-dependent phenomena in solids and provide also information about the underlying electronic band structure. We present a comprehensive set of experimental data for values and anisotropies of the electron and hole Landé factors in hybrid organic-inorganic (MAPbI 3 , MAPb(Br 0.5 Cl 0.5 ) 3 , MAPb(Br 0.05 Cl 0.95 ) 3 , FAPbBr 3 , FA 0.9 Cs 0.1 PbI 2.8 Br 0.2 , MA=methylammonium and FA=formamidinium) and all-inorganic (CsPbBr 3 ) lead halide perovskites, determined by pump-probe Kerr rotation and spin-flip Raman scattering in magnetic fields up to 10 T at cryogenic temperatures. Further, we use first-principles density functional theory (DFT) calculations in combination with tight-binding and k ⋅ p approaches to calculate microscopically the Landé factors. The results demonstrate their universal dependence on the band gap energy across the different perovskite material classes, which can be summarized in a universal semi-phenomenological expression, in good agreement with experiment., (© 2022. The Author(s).)

The outstanding optical quality of lead halide perovskites inspires studies of their potential for the optical control of carrier spins as pursued in other materials. Entering largely uncharted territory, time-resolved pump-probe Kerr rotation is used to explore the coherent spin dynamics of electrons and holes in bulk formamidinium caesium lead iodine bromide (FA 0.9 Cs 0.1 PbI 2.8 Br 0.2 ) and to determine key parameters characterizing interactions of their spins, such as the g-factors and relaxation times. The demonstrated long spin dynamics and narrow g-factor distribution prove the perovskites as promising competitors for conventional semiconductors in spintronics. The dynamic nuclear polarization via spin-oriented holes is realized and the identification of the lead ( 207 Pb) isotope in optically detected nuclear magnetic resonance proves that the hole-nuclei interaction is dominated by the lead ions. A detailed theoretical analysis accounting for the specifics of the lead halide perovskite materials allows the evaluation of the underlying hyperfine interaction constants, both for electrons and holes. Recombination and spin dynamics evidence that at low temperatures, photogenerated electrons and holes are localized at different regions of the perovskite crystal, resulting in their long lifetimes up to 44 μs. The findings form the base for the tailored development of spin-optoelectronic applications for the large family of lead halide perovskites and their nanostructures., (© 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Voltage control of ferromagnetism on the nanometer scale is highly appealing for the development of novel electronic devices with low power consumption, high operation speed, reliable reversibility and compatibility with semiconductor technology. Hybrid structures based on the assembly of ferromagnetic and semiconducting building blocks are expected to show magnetic order as a ferromagnet and to be electrically tunable as a semiconductor. Here, we demonstrate the electrical control of the exchange coupling in a hybrid consisting of a ferromagnetic Co layer and a semiconductor CdTe quantum well, separated by a thin non-magnetic (Cd,Mg)Te barrier. The electric field controls the phononic ac Stark effect-the indirect exchange mechanism that is mediated by elliptically polarized phonons emitted from the ferromagnet. The effective magnetic field of the exchange interaction reaches up to 2.5 Tesla and can be turned on and off by application of 1V bias across the heterostructure.

The coherent spin dynamics of fluorine donor-bound electrons in ZnSe induced by pulsed optical excitation is studied in a perpendicular applied magnetic field. The Larmor precession frequency serves as a measure for the total magnetic field exerted onto the electron spins and, surprisingly, does not increase linearly with the applied field, but shows a step-like behavior with pronounced plateaus, given by multiples of the laser repetition rate. This discretization occurs by a feedback mechanism in which the electron spins polarize the nuclear spins, which in turn generate a local Overhauser field adjusting the total magnetic field accordingly. Varying the optical excitation power, we can control the plateaus, in agreement with our theoretical model. From this model, we trace the observed discretization to the optically induced Stark field, which causes the dynamic nuclear polarization.

Background: Non-communicable diseases (NCD) are now the leading cause of death worldwide. As habits and lifestyle are established in childhood and adolescence, targeting school children before they develop unhealthy habits offers a window of opportunity to halt and reverse the emerging NCD epidemic. However, few experiences from school interventions in low- and middle-income countries have been collected. Therefore, the aim of this study was to review experiences of implementing school-based health promotion interventions to identify barriers and recommendations for future interventions., Methods: A qualitative investigation of 17 school-based health promotion interventions in low- and middle-income countries was conducted. Data were collected through questionnaires (15 project leaders) and in-depth interviews with nine project leaders. The data from the questionnaires and interviews was triangulated and analysed using content analysis, where themes and categories emerging from the material were explored., Results: Three key themes emerged from the data: 1) policy environment and stakeholder engagement, 2) health education sessions, and 3) practical health promotion activities. The themes explored the experiences and lessons learned from 17 school-based health promotion projects in low- and middle-income countries. Stakeholders at different administrative levels were important for the projects; however, stakeholders close to implementation were seen to be more engaged. Most projects conducted traditional health education lectures, which formed the basis of their intervention. Promotion of physical activity and healthy eating through participatory approaches were identified; however, barriers such as lack of areas suitable for physical activity and lack of healthy food alternatives in schools can obstruct the successful implementation of interventions., Conclusions: This study has documented experiences with school-based health promotion in low- and middle-income countries, and has shown that schools can play an important role in facilitating NCD-related behavioural change in children. The study recommends increased emphasis on a whole-school approach where activities focusing on individual behavioural change are supported by interventions improving the structural environment., (© 2015 John Wiley & Sons Ltd.)

We report a case of vertebral tuberculosis in a female patient with polycystic kidney disease (PKD) who had been treated with maintenance hemodialysis for six years. Diagnosis of lumbar bacillary spondylitis was particularly difficult, owing to proximity of polycystic kidneys and spine. After removal of one kidney in which no bacterial focus was found, pain and inflammation persisted. Two months later CT scan and RMN evidence of 4th lumbar vertebral lysis led to performing open vertebral biopsy. Tuberculous lesions were found on this material and antibacillary treatment was begun. This case illustrates the difficulty of diagnosing vertebral tuberculosis in dialysis patients, especially in those with PKD.

The role distinctive features played in the identification of 21 dichotically presented syllable initial English consonants was evaluated. Results were analyzed for the entire stimulus set and for various intra- and inter-manner class comparisons. Consistent with previous dichotic studies of stops alone, stops as a subgroup showed a large right ear advantage, a high incidence of blend errors, and greater accuracy in identification when the competing stimuli contrasted on one (rather than two) distinctive features. Results for manner classes other than stops, for inter-manner comparisons and for the total stimulus set indicated increased correct identification with increasing numbers of distinctive feature differences between the two syllables. Analysis of error patterns revealed that, in addition to the stops, continuants, and stop-continuant, stop-affricate, and stop-nasal pairs revealed significant numbers of blend errors. Error responses also showed a tendency for unmarked feature specifications to predominate significantly over marked feature specifications. Finally, the magnitude of the right ear advantage varied significantly as a function of manner class, but not as a function of number of feature contrasts.

Peritonitis remains the major obstacle to the acceptance of continuous ambulatory peritoneal dialysis as a long-term dialysis technique. In January, 1985, Y connectors were introduced into our continuous ambulatory peritoneal dialysis programme, and a two-year prospective randomized trial for all new patients was initiated in which the Y connection system was compared with the conventional technique in the prevention of peritonitis (group I). At the same time, 16 patients (group II), with a high incidence of peritonitis episodes were switched from the conventional technique to the Y connection system, while 55 patients (group III), remained on the conventional technique. Group IA patients (27 new patients using the Y connection system), developed peritonitis every 23 patient-months. Group IB patients (28 new patients using the conventional technique), developed peritonitis every 12.2 patient-months. The difference between these two sub-groups was statistically significant (P less than 0.02). Before their transfer to the Y connection system, group II patients developed peritonitis every 10 patient-months and thereafter one every 24 patient-months (P less than 0.001). Group III patients were divided into 12 continuous cyclic peritoneal dialysis patients with peritonitis every 24 patients-months, and 43 continuous ambulatory peritoneal dialysis patients with peritonitis every 11.7 patient-months. The Y connector therefore proved to be a simple and safe procedure effective in reducing the peritonitis rate in patients on continuous ambulatory peritoneal dialysis.