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Defects and their interactions in crystalline solids often underpin materialproperties and functionality as they are decisive for stability, result inenhanced diffusion, and act as a reservoir of vacancies. Recently, lithium-richlayered oxides have emerged among the leading candidates for thenext-generation energy storage cathode material, delivering 50 % excesscapacity over commercially used compounds. Oxygen-redox reactions are believedto be responsible for the excess capacity, however, voltage fading hasprevented commercialization of these new materials. Despite extensive researchthe understanding of the mechanisms underpinning oxygen-redox reactions andvoltage fade remain incomplete. Here, using operando three-dimensional Braggcoherent diffractive imaging, we directly observe nucleation of a mobiledislocation network in nanoparticles of lithium-rich layered oxide material.Surprisingly, we find that dislocations form more readily in the lithium-richlayered oxide material as compared with a conventional layered oxide material,suggesting a link between the defects and the anomalously high capacity inlithium-rich layered oxides. The formation of a network of partial dislocationsdramatically alters the local lithium environment and contributes to thevoltage fade. Based on our findings we design and demonstrate a method torecover the original high voltage functionality. Our findings reveal that thevoltage fade in lithium-rich layered oxides is reversible and call for newparadigms for improved design of oxygen-redox active materials.

Symmetry breaking and the emergence of order is one of the most fascinating phenomena in condensed matter physics. It leads to a plethora of intriguing ground states found in antiferromagnets, Mott insulators, superconductors, and density-wave systems. Exploiting states of matter far from equilibrium can provide even more striking routes to symmetry-lowered, ordered states. Here, we demonstrate for the case of elemental chromium that moderate ultrafast photoexcitation can transiently enhance the charge-density-wave (CDW) amplitude by up to 30% above its equilibrium value, while strong excitations lead to an oscillating, large-amplitude CDW state that persists above the equilibrium transition temperature. Both effects result from dynamic electron-phonon interactions, providing an efficient mechanism to selectively transform a broad excitation of the electronic order into a well-defined, long-lived coherent lattice vibration. This mechanism may be exploited to transiently enhance order parameters in other systems with coupled degrees of freedom.

Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformation in individual palladium nanocubes in situ using coherent X-ray diffractive imaging. The phase transformation dynamics, which involve the nucleation and propagation of a hydrogen-rich region, are dependent on absolute time (aging) and involve intermittent dynamics (avalanching). A hydrogen-rich surface layer dominates the crystal strain in the hydrogen-poor phase, while strain inversion occurs at the cube corners in the hydrogen-rich phase. A three-dimensional phase-field model is used to interpret the experimental results. Our experimental and theoretical approach provides a general framework for designing and optimizing phase transformations for single nanocrystals in reactive environments.

We synthesized Ni nanoparticles with an atmospheric-thermal chemical vapor deposition method and investigated their lattice distortions and defects using Bragg coherent diffractive imaging. Because the strain can alter the magnetic properties of ferromagnetic materials, it is important to study the lattice distortion and structural imperfection. As a result of the Bragg coherent diffractive imaging, we found that the Ni nanocubes have a deformation-free zone in the middle. In addition, the defects such as dislocation and twin domain defects were detected in other Ni nanoparticles based on the Bragg diffraction images and patterns. The imaging of nanoparticles can contribute to a better understanding of their growth mechanisms and improve the design and synthesis of nanoparticles. [ABSTRACT FROM AUTHOR]

The article discusses a research study on a group of congenital generalized lipodystrophy (CGL) in l-acyl-sn-glycerol 3-phosphate O-acyltransferase 2 (Agpat2) mice and its pathology. Selected for microijection were Agpat2-null mice and knockout mice for phenotyping were intercrossed then tissues were collected from control mice and knockout mice for immunohistochemistry and histopathologic examination. Conclusions indicated that Agpat2 mice exhibit pathologic and metabolic changes associated with GCL in mouse lipodystrophy models and human cases.

Discontinuous solid-solid phase transformations play a pivotal role in determining the properties of rechargeable battery electrodes. By leveraging operando Bragg Coherent Diffractive Imaging (BCDI), we investigate the discontinuous phase transformation in Li x Ni 0.5 Mn 1.5 O 4 within an operational Li metal coin cell. Throughout Li-intercalation, we directly observe the nucleation and growth of the Li-rich phase within the initially charged Li-poor phase in a 500 nm particle. Supported by the microelasticity model, the operando imaging unveils an evolution from a curved coherent to a planar semi-coherent interface driven by dislocation dynamics. Our data indicates negligible kinetic limitations from interface propagation impacting the transformation kinetics, even at a discharge rate of C/2 (80 mA/g). This study highlights BCDI's capability to decode complex operando diffraction data, offering exciting opportunities to study nanoscale phase transformations with various stimuli., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications., (© 2022 The Ecological Society of America.)

Background: SARS-CoV-2 infection has caused variable clinical outcomes including hospitalization and death. We analyzed state-level data from the North Carolina COVID-19 Surveillance System (NC COVID) to describe demographics of those infected with SARS-CoV-2 and to describe factors associated with infection-fatality in North Carolina., Methods: This was a retrospective cohort study using surveillance data on positive SARS-CoV-2-infected individuals (N = 214,179) identified between March 1, 2020, and September 30, 2020. We present descriptive statistics and associations among demographics, medical comorbidities, and SARS-CoV-2 infection-fatality., Results: Median age for residents with reported SARS-CoV-2 was 38 (IQR 23-54). Age was strongly correlated with SARS-CoV-2 infection-fatality. Greater infection-fatality was noted among those who identified as Black across all comorbidities. Coexisting chronic disease was associated with greater infection-fatality, with kidney disease demonstrating the strongest association., Limitations: A high percentage of missing data for race/ethnicity and comorbidities limits the interpretation of our findings. Data were not available for socioeconomic measures that could aid in better understanding inequities associated with SARS-CoV-2 infection-fatality., Conclusions: Among North Carolinians identified with SARS-CoV-2 via surveillance efforts, age, race, and comorbidities were associated with infection-fatality; these findings are similar to those of studies using different source populations in the United States. In addition to age and other nonmodifiable variables, systematic differences in social conditions and opportunity may increase the risk of SARS-CoV-2 infection-fatality among Black Americans compared to other races/ethnicities., Competing Interests: Funding: This project was supported by a COVID-19 response grant from the North Carolina Policy Collaboratory at the University of North Carolina at Chapel Hill. The findings and conclusions in this publication are those of the authors and do not necessarily represent the views of the North Carolina Department of Health and Human Services, Division of Public Health. Data were sourced from the NCDHHS Division of Public Health. Disclosure of interests: Dr. Denslow, Dr. Rote, Dr. Wingert, and Dr. Sexton report no conflicts of interest or other sources of financial support. Dr. Hanchate receives funding from the NIH, HRSA, Duke Foundation, JPB Foundation, and the Kate B. Reynolds Charitable Trust. He has no conflicts of interest to report. Dr. Lanou receives funding from the Kate B. Reynolds Charitable Trust and the Administration for Community Living and does not have any conflicts of interest or other sources of financial support to report. Dr. Westreich consulted with PRI Healthcare Solutions on behalf of Sanofi-Pasteur within the last 12 months on topics unrelated to COVID-19 and does not have any conflicts of interest to report. Dr. Halladay is an academic researcher with a university faculty appointment as a Full Professor in the Department of Family Medicine at the University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, with current funding support from the Patient Centered Outcomes Research Institute, the National Institutes of Health (NIA and NHLBI), and the Agency for Healthcare and Quality. She does not have any conflicts of interest or other sources of financial support to report., (Copyright ©2023 by the North Carolina Institute of Medicine and The Duke Endowment. All rights reserved.)

A new species of Geophagus sensu stricto is described from the Tapajos River basin, Brazil, elevating the number of species of the genus to 21. The new species is of commercial importance and is known in the aquarist trade as Geophagus 'red head'. The new species is diagnosed using an integrative approach, based on mitochondrial DNA analysis along with morphological evidence. The new species is distinguished from all congeners by the absence of markings on the head, the bar pattern composed by nine vertical bars on the flanks and the presence of distinct longitudinal bands in the caudal fin. Additionally, it shows a genetic distance of at least 2.0% in cytochrome b gene sequences from its closest congeners. Molecular analysis including most genera of Cichlidae from South America corroborates that the new species belongs to the group of Geophagus sensu stricto., (© 2022 Fisheries Society of the British Isles.)

Background: Anticipated and experienced stigma constitute important issues for patients with multiple sclerosis receiving adequate healthcare. Stigma is likely to be associated with lower quality of life in patients with multiple sclerosis, but the underlying mechanisms and contributing factors are unclear., Methods: We conducted a cross-sectional survey among N = 101 patients with a diagnosis of multiple sclerosis in a German outpatient department. Patients completed questionnaires on enacted and self-stigma (SSCI-8), sense of coherence (SOC-L9) and quality of life (MusiQol). Age, sex, disease duration, disability or extent of limitations (EDSS), cognition (SDMT), depression (BDI-II) and fatigue (FSMC) were used as covariates in linear regression and mediation models., Results: 57.3% of patients with MS reported having experienced stigmatization due to MS at least once. Fatigue (b = -0.199, p < 0.001), enacted stigmatization experience (b = -0.627, p = 0.010) and sense of coherence (b = 0.654, p < 0.001) were significant predictors for quality of life. The mediation analysis showed a partial mediation of the association between enacted stigma and quality of life by patients' sense of coherence (direct effect: b = -1.042, t = -4.021, p < 0.001; indirect effect: b = -0.773, CI = -1.351--0.339. The association of self-stigma with quality of life was fully mediated by sense of coherence (b = -1.579, CI = -2.954--0.669)., Conclusion: Patients with multiple sclerosis are affected by stigma, which is associated with lower quality of life. Sense of coherence is a potentially important mediator of stigma and represents a promising target to refine existing stigma interventions and improve the quality of life in these patients., (© 2021. The Author(s).)

Recurrent episodes of decompensated heart failure (HF) represent an emerging cause of hospitalizations in developed countries with an urgent need for effective therapies. Recently, the pregnancy-related hormone relaxin (RLN) was found to mediate cardio-protective effects and act as a positive inotrope in the cardiovascular system. RLN binds to the RLN family peptide receptor 1 (RXFP1), which is predominantly expressed in atrial cardiomyocytes. We therefore hypothesized that ventricular RXFP1 expression might exert potential therapeutic effects in an in vivo model of cardiac dysfunction. Thus, mice were exposed to pressure overload by transverse aortic constriction and treated with AAV9 to ectopically express RXFP1. To activate RXFP1 signaling, RLN was supplemented subcutaneously. Ventricular RXFP1 expression was well tolerated. Additional RLN administration not only abrogated HF progression but restored left ventricular systolic function. In accordance, upregulation of fetal genes and pathological remodeling markers were significantly reduced. In vitro, RLN stimulation of RXFP1-expressing cardiomyocytes induced downstream signaling, resulting in protein kinase A (PKA)-specific phosphorylation of phospholamban (PLB), which was distinguishable from β-adrenergic activation. PLB phosphorylation corresponded to increased calcium amplitude and contractility. In conclusion, our results demonstrate that ligand-activated cardiac RXFP1 gene therapy represents a therapeutic approach to attenuate HF with the potential to adjust therapy by exogenous RLN supplementation., Competing Interests: Declaration of interests N.S., P.S., H.A.K., and P.W.J.R are listed as inventors of a filed patent related to relaxin receptor 1 for use in treatment and prevention of heart failure (PCT/EP2019/081962). The other authors declare no competing interests., (Copyright © 2021 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)

Here, we photoinduce and directly observe with x-ray scattering an ultrafast enhancement of the structural long-range order in the archetypal Mott system V&#95;{2}O&#95;{3}. Despite the ultrafast increase in crystal symmetry, the change of unit cell volume occurs an order of magnitude slower and coincides with the insulator-to-metal transition. The decoupling between the two structural responses in the time domain highlights the existence of a transient photoinduced precursor phase, which is distinct from the two structural phases present in equilibrium. X-ray nanoscopy reveals that acoustic phonons trapped in nanoscale twin domains govern the dynamics of the ultrafast transition into the precursor phase, while nucleation and growth of metallic domains dictate the duration of the slower transition into the metallic phase. The enhancement of the long-range order before completion of the electronic transition demonstrates the critical role the nonequilibrium structural phases play during electronic phase transitions in correlated electrons systems.

The possibility of studying dynamics at time scales on the order of the pulse duration at synchrotron X-ray sources with present avalanche photodiode point detection technology is investigated, without adopting pump-probe techniques. It is found that sample dynamics can be characterized by counting single and double photon events and an analytical approach is developed to estimate the time required for a statistically significant measurement to be made. The amount of scattering required to make such a measurement possible presently within a few days is indicated and it is shown that at next-generation synchrotron sources this time will be reduced dramatically, i.e. by more than three orders of magnitude. The analytical results are confirmed with simulations in the frame of Gaussian statistics. In the future, this approach could be extended to even shorter time scales with the implementation of ultrafast streak cameras.

The recent advent of hard x-ray free electron lasers (XFELs) opens new areas of science due to their exceptional brightness, coherence, and time structure. In principle, such sources enable studies of dynamics of condensed matter systems over times ranging from femtoseconds to seconds. However, the studies of "slow" dynamics in polymeric materials still remain in question due to the characteristics of the XFEL beam and concerns about sample damage. Here we demonstrate the feasibility of measuring the relaxation dynamics of gold nanoparticles suspended in polymer melts using X-ray photon correlation spectroscopy (XPCS), while also monitoring eventual X-ray induced damage. In spite of inherently large pulse-to-pulse intensity and position variations of the XFEL beam, measurements can be realized at slow time scales. The X-ray induced damage and heating are less than initially expected for soft matter materials.

Congenital generalized lipodystrophy (CGL) comprises a heterogeneous group of rare diseases associated with partial or total loss of adipose tissue. Of these, autosomal recessive Berardinelli-Seip congenital lipodystrophy (BSCL) is characterized by the absence of metabolically active subcutaneous and visceral adipose tissues. Metabolic abnormalities associated with lipodystrophy include insulin resistance, hypertriglyceridemia, hepatic steatosis, and diabetes. One form of BSCL has been linked to genetic mutations affecting the lipid biosynthetic enzyme 1-acyl-sn-glycerol 3-phosphate O-acyltransferase 2 (AGPAT2), which is highly expressed in adipose tissue. Precisely how AGPAT2 deficiency causes lipodystrophy remains unresolved, but possible mechanisms include impaired lipogenesis (triglyceride synthesis and storage), blocked adipogenesis (differentiation of preadipocytes to adipocytes), or apoptosis/necrosis of adipocytes. Agpat2(-/-) mice share important pathophysiologic features of CGL previously reported in humans. However, the small white adipose tissue (WAT) depots consisting largely of amoeboid adipocytes with microvesiculated basophilic cytoplasm showed that adipogenesis with deficient lipogenesis was present in all usual locations. Although well-defined lobules of brown adipose tissue (BAT) were present, massive necrosis resulted in early ablation of BAT. Although necrotic or apoptotic adipocytes were not detected in WAT of 10-day-old Agpat2(-/-), the absence of adipocytes in aged mice indicates that these cells must undergo necrosis/apoptosis at some point. Another significant finding in aged lipodystrophic mice was massive pancreatic islet hypertrophy in the face of chronic hyperglycemia, which suggests that glucotoxicity is insufficient by itself to cause β-cell loss and that adipocyte-derived factors help regulate total β-cell mass.

We used gene knockout mice to explore the role of Angiopoietin-like-4 (Angptl4) in lipid metabolism as well as to generate anti-Angptl4 mAbs with pharmacological activity. Angptl4 -/- mice had lower triglyceride (TG) levels resulting both from increased very low-density lipoprotein (VLDL) clearance and decreased VLDL production and had modestly lower cholesterol levels. Also, both Angptl4 -/- suckling mice and adult mice fed a high-fat diet showed reduced viability associated with lipogranulomatous lesions of the intestines and their draining lymphatics and mesenteric lymph nodes. Treating C57BL/6J, ApoE -/-, LDLr -/-, and db/db mice with the anti-Angptl4 mAb 14D12 recapitulated the lipid and histopathologic phenotypes noted in Angptl4 -/- mice. This demonstrates that the knockout phenotype reflects not only the physiologic function of the Angptl4 gene but also predicts the pharmacologic consequences of Angptl4 protein inhibition with a neutralizing antibody in relevant models of human disease.

A thyroid hormone analogue, sodium dextro-triiodothyronine (NaDT3), at a dosage of 1 mg/day for 1 or 2 yr, decreased serum cholesterol levels about 30% in 26 hyperlipidemic adults. There were less sustained decreases in the serum phospholipids, and occasional lowering of the serum triglycerides, but no effects on body weight, blood pressure, or pulse rate. Changes recognized as variable concomitants of spontaneous or induced thyrotoxicosis, such as transient increases in fasting blood glucose, calcium, and globulin, persistent rises in alkaline phosphatase, and nonsustained decreases in hematocrit are consonant with the fact that Na-DT3 exerts about one tenth of the thyroid hormone activity of LT3. These changes, however, appear to represent actions of iodinated amino acids apart from those effects that result in clinical thyrotoxicosis.

The authors investigated a population of identified users of inhalants at a Native American boarding school and compared and contrasted the users to a control group of nonusers. The subjects included 62 adolescents of Native American descent (mean age of 16.6), classified into one nonuser control group (N = 20) and two user groups: onetime users (N = 21) and repeat users (N = 21). Measures of traditional Native American characteristics, desirable physical and psychological assets, academic achievement, grade point average, adherence to school policy, and self-concept were collected on each subject. A one-way analysis of variance was computed to determine the relationship that existed between the research variables and the membership of each subject in his or her respective groups. Findings are discussed, and similarities of the Native American inhalant users to inhalant users in the general adolescent population are noted.