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Importance: While UV radiation displays may be used for recreational purposes at outdoor events, unprotected eyes have been reported to have symptoms consistent with photokeratitis. Such symptoms warrant documentation and evaluation in ophthalmic peer reviewed literature. Objective: To describe a case series of photokeratitis associated with a single ultraviolet radiation display at an outdoor event. Design, Setting, and Participants: This case series involved a retrospective record review of 8 patients who presented in public and private health sectors in November 2023 after developing photokeratitis following UV radiation exposure at an outdoor event in Hong Kong on the night of November 4, 2023. Main Outcomes and Measures: Clinical symptoms, signs, and clinical course of patients who were diagnosed acute photokeratitis following exposure to UV radiation. Results: The mean time of UV display exposure for the 8 patients (mean [SD] age, 33.12 [5.19] years; 4 [50%] female) was 3.00 (1.41) hours, and symptoms presented at a mean (SD) 8.88 (8.24) hours after the exposure. None of the patients were wearing spectacles during the exposed period. All patients were affected bilaterally. All patients experienced eye pain, 6 experienced red eye, and 5 experienced tearing and photophobia. Mean (SD) presenting visual acuity was logMAR 0.10 (0.14) (approximate Snellen equivalent, 20/25) for right eyes and 0.06 (0.89) (approximate Snellen equivalent, 20/25) for left eyes. On examination, there were findings of cornea and conjunctival involvement with punctate epithelial erosions and ciliary vasodilation, but none of the patients presented with anterior chamber reaction. Corticosteroids, lubricants, and antibiotics, all provided topically, were prescribed. Five patients were not scheduled for a review, and 3 had follow-up visits, with the length of follow-up ranging from 7 to 10 days. All patients had undergone a complete recovery. Conclusions and Relevance: These findings provide evidence of an association between UV radiation used for recreational purposes and photokeratitis, which may help guide evaluation and management of future cases.
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Queratitis , Rayos Ultravioleta , Agudeza Visual , Humanos , Femenino , Rayos Ultravioleta/efectos adversos , Masculino , Estudios Retrospectivos , Adulto , Queratitis/etiología , Queratitis/diagnóstico , Hong Kong , Adulto Joven , RecreaciónRESUMEN
Anomalous transport of topological semimetals has generated significant interest for applications in optoelectronics, nanoscale devices, and interconnects. Understanding the origin of novel transport is crucial to engineering the desired material properties, yet their orders of magnitude higher transport than single-particle mobilities remain unexplained. This work demonstrates the dramatic mobility enhancements result from phonons primarily returning momentum to electrons due to phonon-electron dominating over phonon-phonon scattering. Proving this idea, proposed by Peierls in 1932, requires tuning electron and phonon dispersions without changing symmetry, topology, or disorder. This is achieved by combining de Haas - van Alphen (dHvA), electron transport, Raman scattering, and first-principles calculations in the topological semimetals MX2 (M = Nb, Ta and X = Ge, Si). Replacing Ge with Si brings the transport mobilities from an order magnitude larger than single particle ones to nearly balanced. This occurs without changing the crystal structure or topology and with small differences in disorder or Fermi surface. Simultaneously, Raman scattering and first-principles calculations establish phonon-electron dominated scattering only in the MGe2 compounds. Thus, this study proves that phonon-drag is crucial to the transport properties of topological semimetals and provides insight to engineer these materials further.
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For some intermetallic compounds containing lanthanides, structural transitions can result in intermediate electronic states between trivalency and tetravalency; however, this is rarely observed for praseodymium compounds. The dominant trivalency of praseodymium limits potential discoveries of emergent quantum states in itinerant 4f1 systems accessible using Pr4+-based compounds. Here, we use in situ powder x-ray diffraction and in situ electron energy-loss spectroscopy (EELS) to identify an intermetallic example of a dominantly Pr4+ state in the polymorphic system Pr2Co3Ge5. The structure-valence transition from a nearly full Pr4+ electronic state to a typical Pr3+ state shows the potential of Pr-based intermetallic compounds to host valence-unstable states and provides an opportunity to discover previously unknown quantum phenomena. In addition, this work emphasizes the need for complementary techniques like EELS when evaluating the magnetic and electronic properties of Pr intermetallic systems to reveal details easily overlooked when relying on bulk magnetic measurements alone.
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Fe5-xGeTe2 is a promising two-dimensional (2D) van der Waals (vdW) magnet for practical applications, given its magnetic properties. These include Curie temperatures above room temperature, and topological spin texturesâTST (both merons and skyrmions), responsible for a pronounced anomalous Hall effect (AHE) and its topological counterpart (THE), which can be harvested for spintronics. Here, we show that both the AHE and THE can be amplified considerably by just adjusting the thickness of exfoliated Fe5-xGeTe2, with THE becoming observable even in zero magnetic field due to a field-induced unbalance in topological charges. Using a complementary suite of techniques, including electronic transport, Lorentz transmission electron microscopy, and micromagnetic simulations, we reveal the emergence of substantial coercive fields upon exfoliation, which are absent in the bulk, implying thickness-dependent magnetic interactions that affect the TST. We detected a "magic" thickness t ≈ 30 nm where the formation of TST is maximized, inducing large magnitudes for the topological charge density (â¼6.45 × 1020 cm-2), and the concomitant anomalous (ρxyA,max ≃22.6 µΩ cm) and topological (ρxyu,T 1≃5 µΩ cm) Hall resistivities at T ≈ 120 K. These values for ρxyA,max and ρxyu,T are higher than those found in magnetic topological insulators and, so far, the largest reported for 2D magnets. The hitherto unobserved THE under zero magnetic field could provide a platform for the writing and electrical detection of TST aiming at energy-efficient devices based on vdW ferromagnets.
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There is an ongoing interest in kagome materials because they offer tunable platforms at the intersection of magnetism and electron correlation. Herein, we examine single crystals of new kagome materials, LnxCo3(Ge1-ySny)3 (Ln = Y, Gd; y = 0.11, 0.133), which were produced using the Sn flux-growth method. Unlike many of the related chemical analogues with the LnM6X6 formula (M = transition metal and X = Ge, Sn), the Y and Gd analogues crystallize in a hybrid YCo6Ge6/CoSn structure, with Sn substitution. While the Y analogue displays temperature-independent paramagnetism, magnetic measurements of the Gd analogue reveal a magnetic moment of 8.48 µB, indicating a contribution from both Gd and Co. Through anisotropic magnetic measurements, the direction of Co-magnetism can be inferred to be in plane with the kagome net, as the Co contribution is only along H//a. Crystal growth and structure determination of YxCo3(Ge,Sn)3 and GdxCo3(Ge,Sn)3, two new hybrid kagome materials of the CoSn and YCo6Ge6 structure types. Magnetic properties, heat capacity, and resistivity on single crystals are reported.
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Inferior scapula avulsion fractures are rare injuries, with few cases reported and only a small number managed operatively discussed in the literature. We report the case of a man in his 40s who fell from a height and presented with right-sided scapular winging and point tenderness at the inferior pole of his right scapula with no neurological deficit. Radiographs and CT diagnosed avulsion fracture of the inferior scapula. The patient underwent surgical fixation and, following a course of physiotherapy, successfully recovered with no residual winging and full range of movement.
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Fracturas por Avulsión , Fracturas del Hombro , Traumatismos Torácicos , Masculino , Humanos , Fracturas por Avulsión/diagnóstico por imagen , Fracturas por Avulsión/cirugía , Escápula/cirugía , RadiografíaRESUMEN
Gout is one of the most common noncommunicable diseases in Hong Kong. Although effective treatment options are readily available, the management of gout in Hong Kong remains suboptimal. Like other countries, the treatment goal in Hong Kong usually focuses on relieving symptoms of gout but not treating the serum urate level to target. As a result, patients with gout continue to suffer from the debilitating arthritis, as well as the renal, metabolic, and cardiovascular complications associated with gout. The Hong Kong Society of Rheumatology spearheaded the development of these consensus recommendations through a Delphi exercise that involved rheumatologists, primary care physicians, and other specialists in Hong Kong. Recommendations on acute gout management, gout prophylaxis, treatment of hyperuricemia and its precautions, co-administration of non-gout medications with urate-lowering therapy, and lifestyle advice have been included. This paper serves as a reference guide to all healthcare providers who see patients who are at risk and are known to have this chronic but treatable condition.
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Gota , Hiperuricemia , Reumatología , Humanos , Ácido Úrico , Supresores de la Gota/uso terapéutico , Hong Kong , Consenso , Gota/tratamiento farmacológico , Hiperuricemia/complicaciones , Hiperuricemia/tratamiento farmacológicoRESUMEN
STUDY OBJECTIVES: To examine the trajectories of sleep disturbance in cancer survivors during the first 2 years post-treatment and to investigate whether psychological, cognitive, and physical factors differentiate trajectories. METHODS: A total of 623 Chinese cancer survivors of diverse cancer types participated in a 2-year-long prospective study after the completion of cancer treatment. Sleep disturbance was measured using Pittsburgh Sleep Quality Index at 3 (T2), 6 (T3), 12 (T4), 18 (T5), and 24 (T6) months after baseline (within 6-months post-treatment; T1). Latent growth mixture modeling identified distinctive sleep disturbance trajectories and tested if these longitudinal patterns were predicted by baseline psychological distress, attentional control, attentional bias and physical symptom distress and T2 cancer-related distress. Fully adjusted multinomial logistic regression then identified whether these factors differentiated trajectories. RESULTS: Two distinct sleep disturbance trajectories were identified, namely stable good sleepers (69.7%) and persistent high sleep disturbance (30.3%). Compared to those in the stable good sleep group, patients in the persistent high sleep disturbance group were less likely to report avoidant (OR=0.49, 95% CI = 0.26-0.90), while more likely to report intrusive thoughts (OR = 1.76, 95% CI = 1.06-2.92) and cancer-related hyperarousal (OR = 3.37, 95% CI = 1.78-6.38). Higher depression scores also predicted persistent high sleep disturbance group membership (OR = 1.13, 95% CI = 1.03-1.25). Attentional bias, attentional control, anxiety, and physical symptom distress did not predict sleep trajectory membership. CONCLUSIONS: One in three cancer survivors experienced persistent high sleep disturbance. Screening and managing depressive symptoms and cancer-related distress in early cancer rehabilitation may reduce risk of persistent sleep disturbance among cancer survivors.
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Supervivientes de Cáncer , Neoplasias , Trastornos del Sueño-Vigilia , Humanos , Estudios Prospectivos , Trastornos del Sueño-Vigilia/complicaciones , Ansiedad , Sueño , Neoplasias/complicacionesRESUMEN
The detection of adverse drug reactions (ADRs) is critical to our understanding of the safety and risk-benefit profile of medications. With an incidence that has not changed over the last 30 years, ADRs are a significant source of patient morbidity, responsible for 5%-10% of acute care hospital admissions worldwide. Spontaneous reporting of ADRs has long been the standard method of reporting, however this approach is known to have high rates of under-reporting, a problem that limits pharmacovigilance efforts. Automated ADR reporting presents an alternative pathway to increase reporting rates, although this may be limited by over-reporting of other drug-related adverse events. We developed a deep learning natural language processing algorithm to identify ADRs in discharge summaries at a single academic hospital centre. Our model was developed in two stages: first, a pre-trained model (DeBERTa) was further pre-trained on 1.1 million unlabelled clinical documents; secondly, this model was fine-tuned to detect ADR mentions in a corpus of 861 annotated discharge summaries. This model was compared to a version without the pre-training step, and a previously published RoBERTa model pretrained on MIMIC III, which has demonstrated strong performance on other pharmacovigilance tasks. To ensure that our algorithm could differentiate ADRs from other drug-related adverse events, the annotated corpus was enriched for both validated ADR reports and confounding drug-related adverse events using. The final model demonstrated good performance with a ROC-AUC of 0.955 (95% CI 0.933 - 0.978) for the task of identifying discharge summaries containing ADR mentions, significantly outperforming the two comparator models.
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Aprendizaje Profundo , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Procesamiento de Lenguaje Natural , Sistemas de Registro de Reacción Adversa a Medicamentos , Algoritmos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , FarmacovigilanciaRESUMEN
Interlayer excitons, or bound electron-hole pairs whose constituent quasiparticles are located in distinct stacked semiconducting layers, are being intensively studied in heterobilayers of two-dimensional semiconductors. They owe their existence to an intrinsic type-II band alignment between both layers that convert these into p-n junctions. Here, we unveil a pronounced interlayer exciton (IX) in heterobilayers of metal monochalcogenides, namely, γ-InSe on ε-GaSe, whose pronounced emission is adjustable just by varying their thicknesses given their number of layers dependent direct band gaps. Time-dependent photoluminescense spectroscopy unveils considerably longer interlayer exciton lifetimes with respect to intralayer ones, thus confirming their nature. The linear Stark effect yields a bound electron-hole pair whose separation d is just (3.6 ± 0.1) Å with d being very close to dSe = 3.4 Å which is the calculated interfacial Se separation. The envelope of IX is twist-angle-dependent and describable by superimposed emissions that are nearly equally spaced in energy, as if quantized due to localization induced by the small moiré periodicity. These heterostacks are characterized by extremely flat interfacial valence bands making them prime candidates for the observation of magnetism or other correlated electronic phases upon carrier doping.
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Although strongly correlated f-electron systems are well known as reservoirs for quantum phenomena, a persistent challenge is to design specific states. What is often missing are simple ways to determine whether a given compound can be expected to exhibit certain behaviors and what tuning vector(s) would be useful to select the ground state. In this review, we address this question by aggregating information about Ce, Eu, Yb, and U compounds with the ThCr2Si2 structure. We construct electronic/magnetic state maps that are parameterized in terms of unit cell volumes and d-shell filling, which reveals useful trends including that (i) the magnetic and nonmagnetic examples are well separated, and (ii) the crossover regions harbor the examples with exotic states. These insights are used to propose structural/chemical regions of interest in these and related materials, with the goal of accelerating discovery of the next generation of f-electron quantum materials.
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The recent discovery of the A n+1B n X3n+1 (A = lanthanide, B = transition metal, X = tetrel) homologous series provides a new platform to study the structure-property relationships of highly correlated electron systems. Several members of Ce n+1Co n Ge3n+1 (n = 1, 4, 5, 6, and ∞) show evidence of heavy electron behavior with complex magnetic interactions. While the Ce analogues have been investigated, only n = 1, 2, and ∞ of Pr n+1Co n Ge3n+1 have been synthesized, with n = 1 and 2 showing a nonsinglet magnetic ground state. The Pr analogues can provide a platform for direct comparison of highly correlated behavior. In this perspective, we discuss the impetus for synthesizing the Pr n+1Co n Ge3n+1 members and present the structural characterization of the n = 3 and n = 4 members. We lay the foundation for future investigations of the Pr n+1Co n Ge3n+1 family of compounds and highlight the importance of complementary methods to characterize new quantum materials.
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Demonstrating inter-device reliability is essential to use devices interchangeably, and accurately integrate, interpret, or compare data from different actigraphs. Despite this, there is a paucity of comparative literature over a timeframe exceeding one night. The aims of this study were to determine an optimal wake threshold for GENEActiv and to evaluate the concordance between Actiwatch-2 and GENEActiv using a common algorithm (Phillips Respironics). Data were collected from 33 individuals (20 female) aged 20-35 years (M= 25.33, SD = 4.69) across a total 213 nights. Participants wore both devices simultaneously and continuously for seven days. The sleep parameters of interest were: total sleep time, sleep efficiency, sleep onset latency, and wake after sleep onset. Exploratory analyses of sensitivity, specificity, overall accuracy, mean bias, and paired samples t-tests indicated an optimal wake threshold of 115 for GENEActiv, compared with Actiwatch-2 at the 40 (medium, default) threshold. Using these thresholds, sensitivity, and overall accuracy of GENEActiv were both good (86% and 78%, respectively), however specificity was relatively low (40%). There were no significant inter-device differences for any sleep parameters, and all absolute mean biases were small. Overall, the findings from this study provide the first empirical evidence to support the reliability of GENEActiv against Actiwatch-2 over multiple nights using a common algorithm with device-specific wake thresholds.
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Actigrafía , Sueño , Algoritmos , Femenino , Humanos , Polisomnografía , Reproducibilidad de los ResultadosRESUMEN
The BaAl4 prototype structure and its derivatives have been identified to host several topological quantum materials and noncentrosymmetric superconductors. Single crystals up to â¼3 mm × 3 mm × 5 mm of Ln2Co3Ge5 (Ln = Pr, Nd, and Sm) are obtained via flux growth utilizing Sn as metallic flux. The crystal structure is isostructural to the Lu2Co3Si5 structure type in the crystallographic space group C2/c. The temperature-dependent magnetization indicates magnetic ordering at 30 K for all three compounds. Pr2Co3Ge5 and Nd2Co3Ge5 exhibit complex magnetic behavior with spin reorientations before ordering antiferromagnetically around 6 K, whereas Sm2Co3Ge5 shows a clear antiferromagnetic behavior at 26 K. The structures and properties of Ln2Co3Ge5 (Ln = Pr, Nd, and Sm) are compared to those of the ThCr2Si2 and BaNiSn3 structure types. Herein, we present the optimized crystal growth, structure, and physical properties of Ln2Co3Ge5 (Ln = Pr, Nd, and Sm).
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Whereas electron-phonon scattering relaxes the electron's momentum in metals, a perpetual exchange of momentum between phonons and electrons may conserve total momentum and lead to a coupled electron-phonon liquid. Such a phase of matter could be a platform for observing electron hydrodynamics. Here we present evidence of an electron-phonon liquid in the transition metal ditetrelide, NbGe2, from three different experiments. First, quantum oscillations reveal an enhanced quasiparticle mass, which is unexpected in NbGe2 with weak electron-electron correlations, hence pointing at electron-phonon interactions. Second, resistivity measurements exhibit a discrepancy between the experimental data and standard Fermi liquid calculations. Third, Raman scattering shows anomalous temperature dependences of the phonon linewidths that fit an empirical model based on phonon-electron coupling. We discuss structural factors, such as chiral symmetry, short metallic bonds, and a low-symmetry coordination environment as potential design principles for materials with coupled electron-phonon liquid.
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Strongly correlated electrons in layered perovskite structures have been the birthplace of high-temperature superconductivity, spin liquids, and quantum criticality. Specifically, the cuprate materials with layered structures made of corner-sharing square-planar CuO4 units have been intensely studied due to their Mott insulating ground state, which leads to high-temperature superconductivity upon doping. Identifying new compounds with similar lattice and electronic structures has become a challenge in solid-state chemistry. Here, we report the hydrothermal crystal growth of a new copper tellurite sulfate, Cu3(TeO4)(SO4)·H2O, a promising alternative to layered perovskites. The orthorhombic phase (space group Pnma) is made of corrugated layers of corner-sharing CuO4 square-planar units that are edge-shared with TeO4 units. The layers are linked by slabs of corner-sharing CuO4 and SO4. Using both the bond valence sum analysis and magnetization data, we find purely Cu2+ ions within the layers but a mixed valence of Cu2+/Cu+ between the layers. Cu3(TeO4)(SO4)·H2O undergoes an antiferromagnetic transition at TN = 67 K marked by a peak in the magnetic susceptibility. Upon further cooling, a spin-canting transition occurs at T* = 12 K, evidenced by a kink in the heat capacity. The spin-canting transition is explained on the basis of a J1-J2 model of magnetic interactions, which is consistent with the slightly different in-plane superexchange paths. We present Cu3(TeO4)(SO4)·H2O as a promising platform for the future doping and strain experiments that could tune the Mott insulating ground state into superconducting or spin liquid states.
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Ce-based intermetallics are of interest due to the potential to study the interplay of localized magnetic moments and conduction electrons. Our work on Ce-based germanides led to the identification of a new homologous series An+1MnX3n+1 (A = rare earth, M = transition metal, X = tetrels, and n = 1-6). This work presents the single-crystal growth, structure determination, and anisotropic magnetic properties of the n = 4 member of the Cen+1ConGe3n+1 homologous series. Ce5Co4+xGe13-ySny consists of three Ce sites, three Co sites, seven Ge sites, and two Sn sites, and the crystal structure is best modeled in the orthorhombic space group Cmmm where a = 4.3031(8) Å, b = 45.608(13) Å, and c = 4.3264(8) Å, which is in close agreement with the previously reported Sn-free analog where a = 4.265(1) Å, b = 45.175(9) Å, and c = 4.293(3) Å. Anisotropic magnetic measurements show Kondo-like behavior and three magnetic transitions at 6, 4.9, and 2.4 K for Ce5Co4+xGe13-ySny.
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Van der Waals (VdW) materials have opened new directions in the study of low dimensional magnetism. A largely unexplored arena is the intrinsic tuning of VdW magnets toward new ground states. Chromium trihalides provided the first such example with a change of interlayer magnetic coupling emerging upon exfoliation. Here, we take a different approach to engineer previously unknown ground states, not by exfoliation, but by tuning the spin-orbit coupling (SOC) of the nonmagnetic ligand atoms (Cl, Br, I). We synthesize a three-halide series, CrCl3 - x - y Br x I y , and map their magnetic properties as a function of Cl, Br, and I content. The resulting triangular phase diagrams unveil a frustrated regime near CrCl3. First-principles calculations confirm that the frustration is driven by a competition between the chromium and halide SOCs. Furthermore, we reveal a field-induced change of interlayer coupling in the bulk of CrCl3 - x - y Br x I y crystals at the same field as in the exfoliation experiments.
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A new ternary nonstoichiometric Zr6.5Pt6Se19 has been discovered as a part of effort to dope Zr into the layered transitional metal chalcogenide PtSe2. With a new structure type (oC68), it is the first Pt-based ternary chalcogenide with group 4 elements (Ti, Zr, and Hf). The crystal structure adopts the orthorhombic space group Cmmm with lattice parameters of a = 15.637(6) Å, b = 26.541(10) Å, c = 3.6581(12) Å, and V = 1518.2(9) Å3. This unusual structure consists of several building units: chains of edge-sharing selenium trigonal prisms and octahedra centered by zirconium atoms, chains of corner-shared square pyramid, and square planar centered by Pt atoms. The condensation of these building blocks forms a unique structure with bilayered Zr5.54Pt6Se19 slabs stacking along the b direction and large channels parallel to the c direction within the bilayered slabs. Band structure calculations suggest that partial occupancy of Zr atoms creates a pseudo gap at the Fermi level and is likely the main cause for the stability of this new phase.