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Most of kiwifruit cultivars (e.g. Actinidia chinensis cv. Donghong, "DH") were sensitive to waterlogging, thus, waterlogging resistant rootstocks (e.g. Actinidia valvata Dunn, "Dunn") were widely used for kiwifruit industry. Those different species provided ideal materials to understand the waterlogging responses in kiwifruit. Compared to the weaken growth and root activities in "DH", "Dunn" maintained the relative high root activities under the prolonged waterlogging. Based on comparative analysis, transcript levels of pyruvate decarboxylase (PDCs) and alcohol dehydrogenase (ADHs) showed significantly difference between these two species. Both PDCs and ADHs had been significantly increased by waterlogging in "DH", while they were only limitedly triggered by 2 days stress and subsided during the prolonged waterlogging in "Dunn". Thus, 19 differentially expressed transcript factors (DETFs) had been isolated using weighted gene co-expression network analysis combined with transcriptomics and transcript levels of PDCs and ADHs in waterlogged "DH". Among these DETFs, dual luciferase and electrophoretic mobility shift assays indicated AcMYB68 could bind to and trigger the activity of AcPDC2 promoter. The stable over-expression of AcMYB68 significantly up-regulated the transcript levels of PDCs but inhibited the plant growth, especially the roots. Moreover, the enzyme activities of PDC in 35S::AcMYB68 were significantly enhanced during the waterlogging response than that in wild type plants. Most interestingly, comparative analysis indicated that the expression patterns of AcMYB68 and the previously characterized AcERF74/75 (the direct regulator on ADHs) either showed no responses (AcMYB68 and AcERF74) or very limited response (AcERF75) in "Dunn". Taken together, the restricted responses of AcMYB68 and AcERF74/75 in "Dunn" endow its waterlogging tolerance.
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Actinidia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Piruvato Descarboxilase , Actinidia/genética , Actinidia/fisiologia , Actinidia/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Piruvato Descarboxilase/genética , Piruvato Descarboxilase/metabolismo , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Água/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estresse Fisiológico , Regiões Promotoras Genéticas/genéticaRESUMO
Discovered decades ago, the quantum Hall effect remains one of the most studied phenomena in condensed matter physics and is relevant for research areas such as topological phases, strong electron correlations and quantum computing1-5. The quantized electron transport that is characteristic of the quantum Hall effect typically originates from chiral edge states-ballistic conducting channels that emerge when two-dimensional electron systems are subjected to large magnetic fields2. However, whether the quantum Hall effect can be extended to higher dimensions without simply stacking two-dimensional systems is unknown. Here we report evidence of a new type of quantum Hall effect, based on Weyl orbits in nanostructures of the three-dimensional topological semimetal Cd3As2. The Weyl orbits consist of Fermi arcs (open arc-like surface states) on opposite surfaces of the sample connected by one-dimensional chiral Landau levels along the magnetic field through the bulk6,7. This transport through the bulk results in an additional contribution (compared to stacked two-dimensional systems and which depends on the sample thickness) to the quantum phase of the Weyl orbit. Consequently, chiral states can emerge even in the bulk. To measure these quantum phase shifts and search for the associated chiral modes in the bulk, we conduct transport experiments using wedge-shaped Cd3As2 nanostructures with variable thickness. We find that the quantum Hall transport is strongly modulated by the sample thickness. The dependence of the Landau levels on the magnitude and direction of the magnetic field and on the sample thickness agrees with theoretical predictions based on the modified Lifshitz-Onsager relation for the Weyl orbits. Nanostructures of topological semimetals thus provide a way of exploring quantum Hall physics in three-dimensional materials with enhanced tunability.
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BACKGROUND: Cerebral microbleeds (CMB) are indicators of severe cerebral small vessel disease (CSVD) that can be identified through hemosiderin-sensitive sequences in MRI. Specifically, quantitative susceptibility mapping (QSM) and deep learning were applied to detect CMBs in MRI. PURPOSE: To automatically detect CMB on QSM, we proposed a two-stage deep learning pipeline. STUDY TYPE: Retrospective. SUBJECTS: A total number of 1843 CMBs from 393 patients (69 ± 12) with cerebral small vessel disease were included in this study. Seventy-eight subjects (70 ± 13) were used as external testing. FIELD STRENGTH/SEQUENCE: 3 T/QSM. ASSESSMENT: The proposed pipeline consisted of two stages. In stage I, 2.5D fast radial symmetry transform (FRST) algorithm along with a one-layer convolutional network was used to identify CMB candidate regions in QSM images. In stage II, the V-Net was utilized to reduce false positives. The V-Net was trained using CMB and non CMB labels, which allowed for high-level feature extraction and differentiation between CMBs and CMB mimics like vessels. The location of CMB was assessed according to the microbleeds anatomical rating scale (MARS) system. STATISTICAL TESTS: The sensitivity and positive predicative value (PPV) were reported to evaluate the performance of the model. The number of false positive per subject was presented. RESULTS: Our pipeline demonstrated high sensitivities of up to 94.9% at stage I and 93.5% at stage II. The overall sensitivity was 88.9%, and the false positive rate per subject was 2.87. With respect to MARS, sensitivities of above 85% were observed for nine different brain regions. DATA CONCLUSION: We have presented a deep learning pipeline for detecting CMB in the CSVD cohort, along with a semi-automated MARS scoring system using the proposed method. Our results demonstrated the successful application of deep learning for CMB detection on QSM and outperformed previous handcrafted methods. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.
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Hemorragia Cerebral , Doenças de Pequenos Vasos Cerebrais , Aprendizado Profundo , Imageamento por Ressonância Magnética , Humanos , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Idoso , Estudos Retrospectivos , Hemorragia Cerebral/diagnóstico por imagem , Pessoa de Meia-Idade , Algoritmos , Encéfalo/diagnóstico por imagem , Sensibilidade e Especificidade , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/métodosRESUMO
Pb soil pollution poses a serious health risk to both the environment and humans. Immobilization is the most common strategy for remediation of heavy metal polluted soil. In this study, municipal sewage sludge was used as an amendment for rehabilitation of Pb-contaminated soils, for agricultural use, near a lead-acid battery factory. The passivation effect was further improved by the addition of phosphate fertilizer. It was found that the leachable Pb content in soils was decreased from 49.6 mg kg-1 to 16.1-36.6 mg kg-1 after remediation of sludge for 45 d at applied dosage of municipal sewage sludge of 4-16 wt%, and further decreased to 14.3-34.3 mg kg-1 upon extension of the remediation period to 180 d. The addition of phosphate fertilizer greatly enhanced the Pb immobilization, with leachable Pb content decreased to 2.0-23.6 mg kg-1 with increasing dosage of phosphate fertilizer in range of 0.8-16 wt% after 180 d remediation. Plant assays showed that the bioavailability of Pb was significantly reduced by the soil remediation, with the content of absorbed Pb in mung bean roots decreased by as much as 87.0%. The decrease in mobility and biotoxicity of the soil Pb is mainly attributed to the speciation transformation of carbonate, Fe-Mn oxides and organic matter bound Pb to residue Pb under the synergism of reduction effect of sludge and acid dissolution and precipitation effect of phosphate fertilizer. This study suggests a new method for remediation of Pb-contaminated soil and utilization of municipal sewage sludge resources.
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BACKGROUND: The quality of transitional care is closely related to the health outcomes of patients, and understanding the status of transitional care for patients is crucial to improving the health outcomes of patients. Therefore, this study aims to investigate the quality of transitional care in elderly patients with chronic diseases and analyze its influencing factors, to provide a basis for improving transitional care services. METHODS: This is a cross-sectional study. We used the Chinese version of the Partners at Care Transitions Measure (PACT-M) to survey patients with chronic diseases aged 60 years and older who were about to be discharged from five tertiary hospitals in Henan and Shanxi provinces. We used the mean ± standard deviation to describe the quality of transitional care, t-test or one-way ANOVA, and regression analysis to explore the factors affecting the quality of transitional care for patients. RESULTS: 182 elderly patients with chronic diseases aged ≥ 60 years completed the PACT-M survey. The scores of PACT-M1 and PACT-M2 were (30.69 ± 7.87) and (25.59 ± 7.14) points, respectively. The results of the t-test or one-way ANOVA showed that the patient's marital status, ethnicity, religion, educational level, preretirement occupation, residence, household income per month, and living situation had an impact on the quality of transitional care for elderly patients with chronic diseases (P < 0.05). The results of regression analyses showed that patients' preretirement occupation, social support, and health status were the main influences on the quality of transitional care for elderly patients with chronic diseases (P < 0.05), and they explained 63.1% of the total variance. CONCLUSIONS: The quality of transitional care for older patients with chronic illnesses during the transition from hospital to home needs further improvement. Factors affecting the quality of transitional care included patients' pre-retirement occupation, social support, and health status. We can improve the hospital-community-family tertiary linkage service to provide coordinated and continuous transitional care for patients based on their occupation, health status, and social support to enhance the quality of transitional care and the patient's health.
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BACKGROUND: This study explored risk perception characteristics and influencing factors among informal caregivers of functionally dependent elderly individuals at home, aiming to improve caregivers' caregiving risk perception and coping abilities and ultimately enhance the quality of life for these individuals. METHODS: We used purposive sampling to select 22 informal caregivers from a community in Zhengzhou City, Henan Province, China, between March and September 2023 and conducted face-to-face semi-structured in-depth interviews. The data were analyzed using Colaizzi's seven-step analysis method. RESULTS: We extracted two themes, caregiving risk perception characteristics and caregiving risk perception associated factors, and eight sub-themes, perceived risk possibility, perceived risk anticipation, perceived severity of consequences, past caregiving experiences, health literacy, psychological status, caregiving burden, and family social support. CONCLUSION: There were differences in how informal caregivers perceived the risks associated with caring for functionally dependent elderly individuals at home, which various factors could influence. It was essential to provide training that covered the knowledge and skills needed for caregiving, improve caregivers' awareness of safety risks, and establish a correct perception of caregiving risks. The government must construct and refine a comprehensive framework for caregiver respite services. Simultaneously, healthcare professionals should proactively undertake health education endeavors to augment the recognition of care safety risks among informal caregivers, thereby cultivating an accurate awareness of care risk perception.
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Differences in the implementation of the perioperative nutrition guidelines and pathways by caregivers lead to differences in enteral nutrition provided to the patients. This study investigated the effect of a personalized enteral nutrition protocol on the postoperative nutritional status of patients who underwent oral cancer surgery at Zhejiang Ningbo NO. 2 Hospital. Those who underwent surgery between July 2017 and October 2018 received routine enteral nutrition based on the Nutritional Risk Screening 2002 (routine group), while those between November 2018 and August 2021 received personalized enteral nutrition based on the Patient-Generated Subjective Global Assessment tool (personalized group). Seventy patients completed the study (routine group, n = 34; personalized group, n = 36). After surgery, the personalized group exhibited significantly greater improvements in serum albumin levels (P < 0.01) (on the 7th and 10th day) and hand grip strength (P < 0.01), higher self-care ability (P < 0.01), lower incidence of gastrointestinal reactions during enteral feeding (P < 0.05), and shorter hospital stay (P < 0.05) than the routine group. Therefore, a personalized enteral nutrition program might improve the postoperative nutritional status, shorten the hospital stay, and accelerate postoperative recovery in patients who underwent oral cancer surgery.
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Nutrição Enteral , Neoplasias Bucais , Humanos , Nutrição Enteral/métodos , Estado Nutricional , Força da Mão , Tempo de Internação , Neoplasias Bucais/cirurgiaRESUMO
Background: The clinical outcomes of low-grade glioma (LGG) are associated with T cell infiltration, but the specific contribution of heterogeneous T cell types remains unclear. Method: To study the different functions of T cells in LGG, we mapped the single-cell RNA sequencing results of 10 LGG samples to obtain T cell marker genes. In addition, bulk RNA data of 975 LGG samples were collected for model construction. Algorithms such as TIMER, CIBERSORT, QUANTISEQ, MCPCOUTER, XCELL, and EPIC were used to depict the tumor microenvironment landscape. Subsequently, three immunotherapy cohorts, PRJEB23709, GSE78820, and IMvigor210, were used to explore the efficacy of immunotherapy. Results: The Human Primary Cell Atlas was used as a reference dataset to identify each cell cluster; a total of 15 cell clusters were defined and cells in cluster 12 were defined as T cells. According to the distribution of T cell subsets (CD4+ T cell, CD8+ T cell, Naïve T cell, and Treg cell), we selected the differentially expressed genes. Among the CD4+ T cell subsets, we screened 3 T cell-related genes, and the rest were 28, 4, and 13, respectively. Subsequently, according to the T cell marker genes, we screened six genes for constructing the model, namely, RTN1, HERPUD1, MX1, SEC61G, HOPX, and CHI3L1. The ROC curve showed that the predictive ability of the prognostic model for 1, 3, and 5 years was 0.881, 0.817, and 0.749 in the TCGA cohort, respectively. In addition, we found that risk scores were positively correlated with immune infiltration and immune checkpoints. To this end, we obtained three immunotherapy cohorts to verify their predictive ability of immunotherapy effects and found that high-risk patients had better clinical effects of immunotherapy. Conclusion: This single-cell RNA sequencing combined with bulk RNA sequencing may elucidate the composition of the tumor microenvironment and pave the way for the treatment of low-grade gliomas.
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Glioma , Análise da Expressão Gênica de Célula Única , Humanos , Prognóstico , Fatores de Transcrição , Linfócitos T CD4-Positivos , Complexo CD3 , Glioma/genética , Microambiente Tumoral/genética , Canais de Translocação SECRESUMO
When a medical device or surgical instrument comes into contact with the patient's sterile tissue or mucous membrane during the various processes, the risk of introducing infections into the patient's body increases. Furthermore, an infection may be transmitted from one patient to another, from a patient to a member of the medical staff and vice versa or from the environment to the patient via improperly sterilized or disinfected equipment. A number of outbreaks and diseases have been documented in the hospital setting as a result of poorly sanitized devices. As a result, adequate disinfection procedures for medical and surgical items are required in all healthcare facilities. It is equally the responsibility of healthcare providers to reduce and eliminate such infections. Each hospital should have its own standards for sterilization and disinfection of equipment based on the intended use of medical devices and associated infections. In order to reduce the risk of both endogenous and exogenous infections, infection control procedures must be implemented in general practice. Using a formulation containing alcohol alone or in combination with other agents to properly wash hands after each patient's checkup and before any procedure reduces the likelihood of transmitting infections to and from patients. Sterilization and disinfection are the most important aspects of infection control. The most common sterilization methods are steam sterilizers and ethylene dioxide sterilizers. Trash generated during practice should be handled according to protocol and rules, as it may be a source of nosocomial infections. Trained personnel are required to carry out these procedures.
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Infecção Hospitalar , Desinfecção , Humanos , Desinfecção/métodos , Infecção Hospitalar/prevenção & controle , Instrumentos Cirúrgicos , Pessoal de Saúde , Resultado do TratamentoRESUMO
In mitochondria, the major subunits of oxidative phosphorylation complexes are translated by the mitochondrial ribosome (mito-ribosome). The correct insertion and assembly of these subunits into the inner mitochondrial membrane (IMM) are facilitated by mitochondrial oxidase assembly protein 1 (Oxa1) during the translation process. This co-translational insertion process involves an association between the mito-ribosome and the C-terminus of Oxa1 (Oxa1-CTD) Nuclear magnetic resonance (NMR) methods were mainly used to investigate the structural characterization of yeast Oxa1-CTD and its mode of interaction with the E. coli 70S ribosome. Oxa1-CTD forms a transient α-helical structure within the residues P342-Q385, which were reported to form an α-helix when combining with the ribosome. Two conserved contact sites that could interact with the ribosome were further identified. The first site was located on the very end of the N-terminus (V321-I327), and the second one encompassed a stretch of amino acid residues I348-Q370. Based on our discoveries and previous reports, a model has been proposed in which Oxa1-CTD interacts with ribosomes, accompanied by transient-to-stable transitions at the second contact site. These observations may enhance our understanding of the potential role of Oxa1-CTD in facilitating the assembly of oxidative phosphorylation complexes and provide insight into the structural characteristics of Oxa1-CTD.
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Escherichia coli , Proteínas Mitocondriais , Ribossomos , Saccharomyces cerevisiae , Escherichia coli/genética , Escherichia coli/metabolismo , Espectroscopia de Ressonância Magnética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Ribossomos/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismoRESUMO
Currently, two-dimensional (2D) materials with intrinsic antiferromagnetism have stimulated research interest due to their insensitivity to external magnetic fields and absence of stray fields. Here, we predict a family of stable transition metal (TM) borides, TMB12 (TM = V, Cr, Mn, Fe) monolayers, by combining TM atoms and B12 icosahedra based on first-principles calculations. Our results show that the four TMB12 monolayers have stable antiferromagnetic (AFM) ground states with large magnetic anisotropic energy. Among them, three TMB12 (TM=V, Cr, Mn) monolayers display an in-plane easy magnetization axis, while the FeB12 monolayer has an out-of-plane easy magnetization axis. Among them, the CrB12 and the FeB12 monolayers are AFM semiconductors with band gaps of 0.13 eV and 0.35 eV, respectively. In particular, the AFM FeB12 monolayer is a spin-polarized AFM material with a Néel temperature of 125 K. Moreover, the electronic and magnetic properties of the CrB12 and the FeB12 monolayers can be modulated by imposing external biaxial strains. Our findings show that the TMB12 monolayers are candidates for designing 2D AFM materials, with potential applications in electronic devices.
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BACKGROUND: No studies have reported on how to relieve distress or relax in medical health workers while wearing medical protective equipment in coronavirus disease 2019 (COVID-19) pandemic. The study aimed to establish which relaxation technique, among six, is the most feasible in first-line medical health workers wearing medical protective equipment. METHODS: This was a two-step study collecting data with online surveys. Step 1: 15 first-line medical health workers were trained to use six different relaxation techniques and reported the two most feasible techniques while wearing medical protective equipment. Step 2: the most two feasible relaxation techniques revealed by step 1 were quantitatively tested in a sample of 65 medical health workers in terms of efficacy, no space limitation, no time limitation, no body position requirement, no environment limitation to be done, easiness to learn, simplicity, convenience, practicality, and acceptance. RESULTS: Kegel exercise and autogenic relaxation were the most feasible techniques according to step 1. In step 2, Kegel exercise outperformed autogenic relaxation on all the 10 dimensions among the 65 participants while wearing medical protective equipment (efficacy: 24 v. 15, no space limitation: 30 v. 4, no time limitation: 31 v. 4, no body position requirement: 26 v. 4, no environment limitation: 30 v. 11, easiness to learn: 28 v. 5, simplicity: 29 v. 7, convenience: 29 v. 4, practicality: 30 v. 14, acceptance: 32 v. 6). CONCLUSION: Kegel exercise seems a promising self-relaxation technique for first-line medical health workers while wearing medical protective equipment among COVID-19 pandemic.
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COVID-19 , COVID-19/prevenção & controle , Pessoal de Saúde , Humanos , Pandemias/prevenção & controle , Equipamentos de Proteção , Terapia de RelaxamentoRESUMO
BACKGROUND: Coffin-Siris syndrome (CSS) is a rare autosomal dominant disorder characterized by intellectual disability, developmental delay, and characteristic facial features. Few patients with cutaneous phenotype in this rare syndrome have been reported. CASE PRESENTATION: Herein, we describe a 12-year-old Chinese girl diagnosed with CSS, who was referred to our hospital because of intellectual disability and short stature. Prominent characteristics of the cutaneous system were observed: (1) A congenital giant nevus from the left frontal and temporal regions to the entire left scalp; and (2) multiple melanocytic nevi on the face and trunk. Whole exome sequencing revealed a novel heterozygous variant in the ARID1B gene. Recombinant human growth hormone (rhGH) was given for short stature, and resulted in significantly improved height. No enlargement or malignant transformation of nevi occurred within 4 years of follow-up. CONCLUSION: The symptoms in cutaneous system is noteworthy,which may be a neglected phenotype in CSS.The therapeutic response of growth hormone is effective in this patient and no tumor related signs were found.
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Nanismo , Deformidades Congênitas da Mão , Micrognatismo , Nevo Pigmentado , Anormalidades Múltiplas , Criança , Proteínas de Ligação a DNA/genética , Nanismo/genética , Face/anormalidades , Feminino , Deformidades Congênitas da Mão/diagnóstico , Deformidades Congênitas da Mão/genética , Humanos , Deficiência Intelectual , Micrognatismo/genética , Pescoço/anormalidades , Nevo Pigmentado/genética , Fatores de Transcrição/genéticaRESUMO
Light-matter coupling in excitonic materials has been the subject of intense recent investigations due to emergence of new materials. Two-dimensional layered hybrid organic/inorganic perovskites (2D HOIPs) support strongly bound excitons at room temperature with some of the highest oscillator strengths and electric loss tangents among the known excitonic materials. Here, we report strong light-matter coupling in Ruddlesden-Popper phase 2D HOIP crystals without the necessity of an external cavity. We report the concurrent occurrence of multiple orders of hybrid light-matter states via both reflectance and luminescence spectroscopy in thick (>100 nm) crystals and near-unity absorption in thin (<20 nm) crystals. We observe resonances with quality factors of >250 in hybridized exciton-polaritons and identify a linear correlation between exciton-polariton mode splitting and extinction coefficient of the various 2D HOIPs. Our work opens the door to studying polariton dynamics in self-hybridized and open cavity systems with broad applications in optoelectronics and photochemistry.
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OBJECTIVES: To study the clinical features and fibroblast growth factor receptor 3 (FGFR3) gene mutations of children with achondroplasia (ACH) through an analysis of 17 cases. METHODS: A retrospective analysis was performed on the clinical data and FGFR3 gene detection results of 17 children with ACH who were diagnosed from January 2009 to October 2021. RESULTS: Of the 17 children with ACH, common clinical manifestations included disproportionate short stature (100%, 17/17), macrocephaly (100%, 17/17), trident hand (82%, 14/17), and genu varum (88%, 15/17). The common imaging findings were rhizomelic shortening of the long bones (100%, 17/17) and narrowing of the lumbar intervertebral space (88%, 15/17). Major complications included skeletal dysplasia (100%, 17/17), middle ear dysfunction (82%, 14/17), motor/language developmental delay (88%, 15/17), chronic pain (59%, 10/17), sleep apnea (53%, 9/17), obesity (41%, 7/17), foramen magnum stenosis (35%, 6/17), and hydrocephalus (24%, 4/17). All 17 children (100%) had FGFR3 mutations, among whom 13 had c.1138G>A hotspot mutations of the FGFR3 gene, 2 had c.1138G>C mutations of the FGFR3 gene, and 2 had unreported mutations, with c.1252C>T mutations of the FGFR3 gene in one child and c.445+2_445+5delTAGG mutations of the FGFR3 gene in the other child. CONCLUSIONS: This study identifies the unreported mutation sites of the FGFR3 gene, which extends the gene mutation spectrum of ACH. ACH is a progressive disease requiring lifelong management through multidisciplinary collaboration.
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Acondroplasia , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos , Acondroplasia/diagnóstico , Acondroplasia/genética , Criança , Humanos , Mutação , Osteocondrodisplasias/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Estudos RetrospectivosRESUMO
We have developed a sensitive cryogenic second-harmonic generation microscopy to study a van der Waals antiferromagnet MnPS_{3}. We find that long-range Néel antiferromagnetic order develops from the bulk crystal down to the bilayer, while it is absent in the monolayer. Before entering the long-range antiferromagnetic ordered phase in all samples, an upturn of the second harmonic generation below 200 K indicates the formation of the short-range order and magnetoelastic coupling. We also directly image the two antiphase (180°) antiferromagnetic domains and thermally induced domain switching down to bilayer. An anomalous mirror symmetry breaking shows up in samples thinner than ten layers for the temperature both above and below the Néel temperature, which indicates a structural change in few-layer samples. Minimal change of the second harmonic generation polar patterns in strain tuning experiments indicate that the symmetry crossover at ten layers is most likely an intrinsic property of MnPS_{3} instead of an extrinsic origin of substrate-induced strain. Our results show that second harmonic generation microscopy is a direct tool for studying antiferromagnetic domains in atomically thin materials, and opens a new way to study two-dimensional antiferromagnets.
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BACKGROUND: The use of phytochemicals for the treatment of various bodily ailments has been in practice since ancient days. Even though in practice, scientific studies on the protective effect of ß-glucogallin (BG) against glaucoma is limited. OBJECTIVES: In the present study, the in vitro glaucoma model (hydrostatic pressure) using PC12 neuronal cells exposed to BG were used to elucidate its protective effects. METHOD: The cultured cells were analyzed for the mitochondrial responses, oxidant-antioxidant status, and expression of caveolin-1, ANGPTL7, the glaucoma markers, and cytokines. RESULTS: We demonstrated a significant increase in the expression of glial fibrillary acidic protein, ANGPTL7, with altered mitochondrial enzymes in glaucoma cells compared to the control. Moreover, cells predisposed to hydrostatic pressure demonstrated an increase in oxidative stress with augmented (p < 0.01) inflammatory cytokines such as IL-2, CXCR4, IL-6, IL-8, MCP-1, and TNF-α. On the other hand, cells pretreated with BG attenuated the reactive oxygen species levels with improved antioxidant enzymes. Simultaneously, the levels of inflammatory cytokines and ANGPTL7 proteins were found attenuated with restored mitochondrial responses in BG pretreated cells. CONCLUSION: Thus, the results of the present study demonstrate that the use of BG on retinal cells against relieving the intraocular pressure may be a promising therapeutic for controlling the disease progression.
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van der Waals (vdW) semiconductors are attractive for highly scaled devices and heterogeneous integration as they can be isolated into self-passivated, two-dimensional (2D) layers that enable superior electrostatic control. These attributes have led to numerous demonstrations of field-effect devices ranging from transistors to triodes. By exploiting the controlled, substitutional doping schemes in covalently bonded, three-dimensional (3D) semiconductors and the passivated surfaces of 2D semiconductors, one can construct devices that can exceed performance metrics of "all-2D" vdW heterojunctions. Here, we demonstrate 2D/3D semiconductor heterojunctions using MoS2 as the prototypical 2D semiconductor laid upon Si and GaN as the 3D semiconductor layers. By tuning the Fermi levels in MoS2, we demonstrate devices that concurrently exhibit over 7 orders of magnitude modulation in rectification ratios and conductance. Our results further suggest that the interface quality does not necessarily affect Fermi level tuning at the junction, opening up possibilities for novel 2D/3D heterojunction device architectures.
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Electro-dewatering (EDW) is an emerging technology for improved sludge/sediment dewatering enabling subsequent cost effective treatment for toxicity and pathogenic reduction if required and/or disposal, but the effects of sediment/sludge properties on the efficacy of EDW remain unclear. Here we investigate EDW in the absence of chemical conditioning which can result in secondary pollution. The influence of sediment/sludge volatile solids content (VS), electrical conductivity (EC), pH and zeta potential (ζ), on mechanical and electrical behaviors determining dewaterability and energy consumption (PE) was investigated. Optimization of EDW parameters increased the final solids content (DSf) from 40 wt% to more than 55 wt% for river sediment, while the solids content in municipal sludge was only increased from 10 wt% to 15-20 wt%. Multiple linear regression and statistical analysis showed that electro-dewatering performance is primarily affected by VS and PE is mainly affected by EC. A theoretical basis for engineering design and selection of operational parameters for sludge/sediment electro-dewatering is provided by this study.
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Esgotos , Eliminação de Resíduos Líquidos , Condutividade Elétrica , Eletricidade , Rios , ÁguaRESUMO
Two-dimensional (2D) van der Waals (vdW) materials show a range of profound physical properties that can be tailored through their incorporation in heterostructures and manipulated with external forces. The recent discovery of long-range ferromagnetic order down to atomic layers provides an additional degree of freedom in engineering 2D materials and their heterostructure devices for spintronics, valleytronics, and magnetic tunnel junction switches. Here, using direct imaging by cryo-Lorentz transmission electron microscopy we show that topologically nontrivial magnetic-spin states, skyrmionic bubbles, can be realized in exfoliated insulating 2D vdW Cr2Ge2Te6. Due to the competition between dipolar interactions and uniaxial magnetic anisotropy, hexagonally packed nanoscale bubble lattices emerge by field cooling with magnetic field applied along the out-of-plane direction. Despite a range of topological spin textures in stripe domains arising due to pair formation and annihilation of Bloch lines, bubble lattices with single chirality are prevalent. Our observation of topologically nontrivial homochiral skyrmionic bubbles in exfoliated vdW materials provides a new avenue for novel quantum states in atomically thin insulators for magneto-electronic and quantum devices.