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1.
Nano Lett ; 23(19): 8833-8841, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37726204

RESUMEN

Moiré superlattices induced by twisted van der Waals (vdW) heterostructures or homostructures have recently gained significant attention due to their potential to generate exotic strong-correlation electronic and phonon phenomena. However, the lack of dynamic tuning for interlayer coupling of moiré superlattices hinders a thorough understanding and development of the moiré correlation state. Here, we present a dynamic tuning method for twisted WSe2/WSe2 homobilayers using a diamond anvil cell (DAC). We demonstrate the powerful tuning of interlayer coupling and observe an enhanced response to pressure for interlayer breathing modes and the rapid descent of indirect excitons in twisted WSe2/WSe2 homobilayers. Our findings indicate that the introduction of a moiré superlattice for WSe2 bilayers gives rise to hybridized excitons, which lead to the different pressure-evolution exciton behaviors compared to natural WSe2 bilayers. Our results provide a novel understanding of moiré physics and offer an effective method to tune interlayer coupling of moiré superlattices.

2.
Small ; 19(26): e2207988, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36938893

RESUMEN

The exploration of moiré superlatticesholds promising potential to uncover novel quantum phenomena emerging from the interplay of atomic structure and electronic correlation . However, the impact of the moiré potential modulation on the number of twisted layers has yet to be experimentally explored. Here, this work synthesizes a twisted WSe2 homotrilayer using a dry-transfer method and investigates the enhancement of the moiré potential with increasing number of twisted layers. The results of the study reveal the presence of multiple exciton resonances with positive or negative circularly polarized emission in the WSe2 homostructure with small twist angles, which are attributed to the excitonic ground and excited states confined to the moiré potential. The distinct g-factor observed in the magneto-optical spectroscopy is also shown to be a result of the confinement of the exciton in the moiré potential. The moiré potential depths of the twisted bilayer and trilayer homostructures are found to be 111 and 212 meV, respectively, an increase of 91% from the bilayer structure. These findings demonstrate that the depth of the moiré potential can be manipulated by adjusting the number of stacked layers, providing a promising avenue for exploration into highly correlated quantum phenomena.

3.
Cardiovasc Diabetol ; 22(1): 42, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36859269

RESUMEN

BACKGROUND: The prevalence of prediabetes is increasing in young adults and patients undergoing coronary angiography. However, whether prediabetes is a considerable risk factor for all-cause mortality remains undetermined in young patients undergoing coronary angiography. METHODS: In this study, we retrospectively included 8868 young patients (men aged < 45 years, women aged < 55 years) who underwent coronary angiography (CAG). Patients were categorized as normoglycemic, prediabetes and diabetes according to the HbA1c level or documented history of diabetes. The association of all-cause mortality with diabetes and prediabetes was detected by Cox proportional hazards regression analysis. RESULTS: A total of 3240 (36.5%) among 8868 young patients receiving CAG were prediabetes and 2218 (25.0%) were diabetes. 728 patients died during a median follow-up of 4.92 years. Compared to the normoglycemic group, prediabetes increased the risk of all-cause mortality in young CAG patients by 24%(adjusted HR: 1.24, 95% CI: 1.04-1.49, p = 0.019) and diabetes increased the risk of all-cause mortality by 46%(adjusted HR:1.46, 95% CI:1.2-1.79, p < 0.001). Subgroup analysis showed that diabetes and prediabetes increased the risk of death mainly in patients without comorbidities. CONCLUSION: Prediabetes accounts for more than one-third of the young adults undergoing CAG and was associated with an increased risk of all-cause mortality, active prevention strategy should be considered for these patients.


Asunto(s)
Estado Prediabético , Masculino , Adulto Joven , Humanos , Femenino , Angiografía Coronaria , Vasos Coronarios , Estudios Retrospectivos , China
4.
Opt Lett ; 48(9): 2393-2396, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37126281

RESUMEN

Monolayer transition metal dichalcogenides (TMDs) have a crystalline structure with broken spatial inversion symmetry, making them promising candidates for valleytronic applications. However, the degree of valley polarization is usually not high due to the presence of intervalley scattering. Here, we use the nanoindentation technique to fabricate strained structures of WSe2 on Au arrays, thus demonstrating the generation and detection of strained localized excitons in monolayer WSe2. Enhanced emission of strain-localized excitons was observed as two sharp photoluminescence (PL) peaks measured using low-temperature PL spectroscopy. We attribute these emerging sharp peaks to excitons trapped in potential wells formed by local strains. Furthermore, the valley polarization of monolayer WSe2 is modulated by a magnetic field, and the valley polarization of strained localized excitons is increased, with a high value of up to approximately 79.6%. Our results show that tunable valley polarization and localized excitons can be realized in WSe2 monolayers, which may be useful for valleytronic applications.

5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(10): 1270-1274, 2023 Oct 10.
Artículo en Zh | MEDLINE | ID: mdl-37730229

RESUMEN

OBJECTIVE: To investigate the clinical features and genetic variant of a child with X-linked dominant Alport syndrome (XLAS). METHODS: A child who had presented at the First Affiliated Hospital of Zhengzhou University in May 2019 was selected as the study subject. Clinical data of the child was collected. Next generation sequencing (NGS) was carried out for the child. Candidate variants were validated by Sanger sequencing of his family members. RESULTS: The child, a 12-year-old boy, had mainly manifested gross hematuria, proteinuria, nephrotic syndrome, and progressive renal impairment in conjunct with hearing loss. Kidney biopsy has revealed uneven glomerular basement membrane thickness. DNA sequencing revealed that the child and his mother have both carried a heterozygous c.2632G>A (p.G878R) variant of the COL4A5 gene, for which his father and brother were of the wild type. This variant was unreported previously. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was classified as pathogenic (PS1+PM1+PM2_Supporting+PP3). CONCLUSION: The maternally derived hemizygous c.2632G>A (p.G878R) variant of the COL4A5 gene probably underlay the XLAS in this child. Above finding has enriched the mutational spectrum of the COL4A5 gene.


Asunto(s)
Sordera , Nefritis Hereditaria , Masculino , Femenino , Humanos , Niño , Nefritis Hereditaria/genética , Glomérulos Renales , Genómica , Madres
6.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6257-6268, 2023 Dec.
Artículo en Zh | MEDLINE | ID: mdl-38211982

RESUMEN

According to the systematic review of text and opinion(SrTO) developed by the Joanna Briggs Institute(JBI), this study integrated the evidence of the medical cases, papers, medical experience, and other related research of famous experts and schools on the treatment of chronic renal failure in the field of traditional Chinese medicine(TCM) nephropathy, analyzed the academic characteristics and influencing factors from the aspects of the principle, method, recipe, and medicines, and explored the internal logic and law of inheritance and innovation in TCM nephropathy. A total of 36 famous TCM experts and 4 schools were included. The work areas are concentrated in North and South China. 94.0% of the famous TCM experts have experienced master-disciple teaching. 27.8% have studied TCM through family succession. 38.9% have been taught by multiple famous teachers. And 5.6% have not experienced master-disciple teaching. In terms of principle, method, recipe, and medicines, many innovations have been made, with 30.6% of famous TCM experts proposing new theories, 11.1% advocating staged treatment of chronic renal failure, and 47.2% summarizing the treatment methods. The formation of the academic thoughts of contemporary famous TCM experts and schools on the treatment of chronic renal failure is closely related to the learning mode, era, and work area. Contemporary famous TCM experts and schools have the academic characteristics of combining classical and clinical theories and paying more attention to TCM with western medicine supplemented. The field of TCM nephropathy has the characteristics of simultaneous inheritance and innovation. On the basis of inheriting the classical theories of TCM, it absorbs modern medical theories, combines clinical diagnosis with the syndrome and treatment law of contemporary diseases, and makes innovations in principle, method, recipe, and medicines, which has significant clinical efficacy in the treatment of chronic renal failure.


Asunto(s)
Medicamentos Herbarios Chinos , Fallo Renal Crónico , Humanos , Medicina Tradicional China , Instituciones Académicas , China , Fallo Renal Crónico/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico
7.
Plant Physiol ; 187(3): 1812-1833, 2021 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-34618071

RESUMEN

Improving photosynthesis is considered a major and feasible option to dramatically increase crop yield potential. Increased atmospheric CO2 concentration often stimulates both photosynthesis and crop yield, but decreases protein content in the main C3 cereal crops. This decreased protein content in crops constrains the benefits of elevated CO2 on crop yield and affects their nutritional value for humans. To support studies of photosynthetic nitrogen assimilation and its complex interaction with photosynthetic carbon metabolism for crop improvement, we developed a dynamic systems model of plant primary metabolism, which includes the Calvin-Benson cycle, the photorespiration pathway, starch synthesis, glycolysis-gluconeogenesis, the tricarboxylic acid cycle, and chloroplastic nitrogen assimilation. This model successfully captures responses of net photosynthetic CO2 uptake rate (A), respiration rate, and nitrogen assimilation rate to different irradiance and CO2 levels. We then used this model to predict inhibition of nitrogen assimilation under elevated CO2. The potential mechanisms underlying inhibited nitrogen assimilation under elevated CO2 were further explored with this model. Simulations suggest that enhancing the supply of α-ketoglutarate is a potential strategy to maintain high rates of nitrogen assimilation under elevated CO2. This model can be used as a heuristic tool to support research on interactions between photosynthesis, respiration, and nitrogen assimilation. It also provides a basic framework to support the design and engineering of C3 plant primary metabolism for enhanced photosynthetic efficiency and nitrogen assimilation in the coming high-CO2 world.


Asunto(s)
Cloroplastos/metabolismo , Producción de Cultivos/métodos , Productos Agrícolas/metabolismo , Nitrógeno/metabolismo , Dióxido de Carbono/metabolismo , Modelos Biológicos
8.
Environ Res ; 213: 113652, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35700767

RESUMEN

Fine particulate matter (PM2.5) can induce the generation of reactive oxygen species (ROS) and damage human tissues. Fully understanding the generation mechanism of oxidative toxicity of PM is challenging due to the extremely complex composition. Classification methods may be helpful in understanding the ROS production mechanisms of complex PM. This study used a solvent extraction and solid phase extraction methods to separate five different components from PM2.5 includes non-extractable components that have rarely been studied before, and discussed the coupling effect and heterogeneous characteristics of oxidation activity they produced. It is found that the water-soluble component contribute about half of the PM oxidation activity, and metal ions probably contribute most of the oxidation activity. Experimental results show that oxygen molecules is the main precursor of ROS production, which depends on whether the aerosol component has catalytic conversion ability. After mixing humic-like substance (HULIS) and hydrophilic water-soluble (HP-WSM) PM, the oxidation activity increased, it is most likely to be a synergistic effect between HULIS and metal ions is dominant, but limited contribution to oxidation activity. It turns out that the non-extractable and water-insoluble components have higher oxidation activity than the water-soluble components, and the two components exhibited a more durable ability to produce 1O2. The reaction of soluble components to produce ROS is homogeneous, but it is obviously heterogeneous for these insoluble components. This study suggests that future attention should be paid to the oxidative toxicity of the non-extractable component, and that single PM component or compound cannot simply be studied independently.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Humanos , Sustancias Húmicas/análisis , Oxidación-Reducción , Material Particulado/análisis , Material Particulado/toxicidad , Especies Reactivas de Oxígeno/análisis , Agua
9.
BMC Urol ; 22(1): 72, 2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35488246

RESUMEN

BACKGROUND: The advantages and disadvantages of transperineal and transrectal biopsies remain controversial in the era of prostate targeted biopsy. In this study, we compared the cancer detection and complication rates of transperineal magnetic resonance/ultrasound (MR/US) fusion biopsy and transrectal cognitive fusion biopsy of the prostate. METHODS: This was a comparative study of two prospectively collected cohorts. Men with clinically suspected prostate cancer and prostate imaging reporting and data system (PI-RADS) score ≥ 3 lesions on multi-parametric magnetic resonance imaging (mpMRI) were enrolled. They underwent either transperineal software fusion biopsy or transrectal cognitive fusion biopsy and systematic biopsy. The detection rates of any prostate cancer and clinically significant prostate cancer (csPC, defined as Gleason score ≥ 3 + 4) and the complication rates between both groups were analysed. RESULTS: Ninety-two and 85 patients underwent transperineal software fusion and transrectal cognitive fusion biopsies, respectively. The detection rate for any prostate cancer was similar between both groups (60.8% vs. 56.4%, p = 0.659). In terms of csPC detection, transperineal fusion biopsy outperformed transrectal fusion biopsy (52.2% vs. 36.5%, p = 0.036). In multivariate regression analysis, age, PI-RADS score > 3, and transperineal route were significant predictors of csPC. Meanwhile, transperineal biopsy resulted in a higher rate of urinary retention than transrectal biopsy (18.5% vs. 4.7%, p = 0.009). No serious infectious complications were noted, although a patient developed sepsis after transrectal biopsy. CONCLUSIONS: Transperineal software fusion biopsy provided a higher csPC detection rate than transrectal cognitive fusion biopsy and carried minimal risk for infectious complications in patients with MRI-visible prostate lesions.


Asunto(s)
Próstata , Neoplasias de la Próstata , Cognición , Humanos , Biopsia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Masculino , Próstata/diagnóstico por imagen , Próstata/patología , Neoplasias de la Próstata/patología , Programas Informáticos
10.
Molecules ; 27(21)2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36364273

RESUMEN

Vanadomolybdates (VMos), comprised of Mo and V in high valences with O bridges, are one of the most important types of polyoxometalates (POMs), which have high activity due to their strong capabilities of gaining/losing electrons. Compared with other POMs, the preparation of VMos is difficult due to their relatively low structural stability, especially those with unclassical architectures. To overcome this shortcoming, in this study, triol ligands were applied to synthesize VMos through a beaker reaction in the presence of V2O5, Na2MoO4, and organic species in the aqueous solution. The single-crystal X-ray diffraction results indicate that two VMo clusters, Na4{V5Mo2O19[CH3C(CH2O)3]}∙13H2O and Na4{V5Mo2O19[CH3CH2C(CH2O)3]}∙13H2O, with a similar architecture, were synthesized, which were both stabilized by triol ligand and {MoO6} polyhedron. Both clusters are composed of five V ions and one Mo ion in a classical Lindqvist arrangement with an additional Mo ion, showing an unprecedented hepta-nuclear VMo structure. The counter Na+ cations assemble into one-dimensional channels, which facilitates the transport of protons and was further confirmed by proton conductivity experiments. The present results provide a new strategy to prepare and stabilize VMos, which is applicable for developing other compounds, especially those with untraditional architectures.

11.
Phys Rev Lett ; 126(15): 155701, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33929239

RESUMEN

The layered crystal of EuSn_{2}As_{2} has a Bi_{2}Te_{3}-type structure in rhombohedral (R3[over ¯]m) symmetry and has been confirmed to be an intrinsic magnetic topological insulator at ambient conditions. Combining ab initio calculations and in situ x-ray diffraction measurements, we identify a new monoclinic EuSn_{2}As_{2} structure in C2/m symmetry above ∼14 GPa. It has a three-dimensional network made up of honeycomblike Sn sheets and zigzag As chains, transformed from the layered EuSn_{2}As_{2} via a two-stage reconstruction mechanism with the connecting of Sn-Sn and As-As atoms successively between the buckled SnAs layers. Its dynamic structural stability has been verified by phonon mode analysis. Electrical resistance measurements reveal an insulator-metal-superconductor transition at low temperature around 5 and 15 GPa, respectively, according to the structural conversion, and the superconductivity with a T_{C} value of ∼4 K is observed up to 30.8 GPa. These results establish a high-pressure EuSn_{2}As_{2} phase with intriguing structural and electronic properties and expand our understandings about the layered magnetic topological insulators.

12.
Cancer Control ; 28: 10732748211026671, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34263661

RESUMEN

OBJECTIVE: Patients with lung cancer are at risk of radiation pneumonia (RP) after receiving radiotherapy. We established a prediction model according to the critical indicators extracted from radiation pneumonia patients. MATERIALS AND METHODS: 74 radiation pneumonia patients were involved in the training set. Firstly, the clinical data, hematological and radiation dose parameters of the 74 patients were screened by Logistics regression univariate analysis according to the level of radiation pneumonia. Next, Stepwise regression analysis was utilized to construct the regression model. Then, the influence of continuous variables on RP was tested by smoothing function. Finally, the model was externally verified by 30 patients in validation set and visualized by R code. RESULTS: In the training set, there was 40 patients suffered≥ level 2 acute radiation pneumonia. Clinical data (diabetes), blood indexes (lymphocyte percentage, basophil percentage, platelet count) and radiation dose (V15 > 40%, V20 > 30%, V35 >18%, V40 > 15%) were related to radiation pneumonia (P < 0.05). Particularly, stepwise regression analysis indicated that the history of diabetes, the basophils percentage, platelet count and V20 could be the best combination used for predicting radiation pneumonia. The column chart was obtained by fitting the regression model with the combined indicator. The receiver operating characteristic (ROC) curve showed that the AUC in the development term was 0.853, the AUC was 0.656 in the validation term. And calibration curves of both groups showed the high stability in efficiently diagnostic. Furthermore, the DCA curve showed that the model had a satisfactory positive net benefit. CONCLUSION: The combination of the basophils percentage, platelet count and V20 is available to build a predictive model of radiation pneumonia for patients with advanced lung cancer.


Asunto(s)
Neoplasias Pulmonares/radioterapia , Neumonitis por Radiación/epidemiología , Anciano , Comorbilidad , Femenino , Pruebas Hematológicas , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Estadificación de Neoplasias , Pronóstico , Curva ROC , Dosificación Radioterapéutica , Estudios Retrospectivos
13.
Nano Lett ; 20(9): 6824-6830, 2020 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-32816495

RESUMEN

Light-emitting diodes (LEDs) based on III-V/II-VI materials have delivered a compelling performance in the mid-infrared (mid-IR) region, which enabled wide-ranging applications in sensing, including environmental monitoring, defense, and medical diagnostics. Continued efforts are underway to realize on-chip sensors via heterogeneous integration of mid-IR emitters on a silicon photonic chip, but the uptake of such an approach is limited by the high costs and interfacial strains, associated with the processes of heterogeneous integrations. Here, the black phosphorus (BP)-based van der Waals (vdW) heterostructures are exploited as room-temperature LEDs. The demonstrated devices emit linearly polarized light, and the spectra cover the technologically important mid-IR atmospheric window. Additionally, the BP LEDs exhibit fast modulation speed and exceptional operation stability. The measured peak extrinsic quantum efficiency is comparable to the III-V/II-VI mid-IR LEDs. By leveraging the integrability of vdW heterostructures, we further demonstrate a silicon photonic waveguide-integrated BP LED.

14.
Exp Eye Res ; 193: 107991, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32142723

RESUMEN

Choroidal neovascularization (CNV) is an acknowledged pathogenic mechanism of various ocular diseases, and in situ cells and mobilized bone marrow-derived cells (BMCs) are thought to participate in this process. We aimed to evaluate the roles of integrin α5 in BMCs and vascular endothelial cells (VECs) in the CNV process mediated by SDF-1/CXCR4 signaling. Adult wild-type mice were engrafted with whole BMCs obtained from GFP transgenic mice and then laser injured to induce CNV. BMCs and RF/6A cells were cultured to discover the mechanism of CNV in vitro. BMCs were mobilized to CNV areas, which expressed elevated SDF-1 and CXCR4. When SDF-1 was intravitreally injected, the number of BMCs was profoundly increased. In the SDF-1-treated group, the levels of integrin α5 expressed on BMCs and VECs were significantly higher than those on the cells in the control group. SDF-1 significantly increased the expression and positive ratio of integrin α5, which was involved in the recruitment and differentiation of BMCs into BMC-derived VECs, and these effects were suppressed by the CXCR4 inhibitor AMD3100. The PI3K/AKT pathway rather than the ERK pathway mediated SDF-1/CXCR4 induction of integrin α5. Integrin α5 suppression efficiently prevented the production of TGF-ß and bFGF but not VEGF. Inhibiting the SDF-1/CXCR4-PI3K/AKT-integrin α5 axis reduced CNV severity. Integrin α5 participates in BMC recruitment and differentiation in SDF-1/CXCR4-induced CNV and inhibition of this pathway may be a new approach to inhibit CNV.


Asunto(s)
Células de la Médula Ósea/citología , Neovascularización Coroidal/genética , Regulación de la Expresión Génica , Integrina alfa5beta1/genética , Animales , Western Blotting , Diferenciación Celular , Movimiento Celular , Células Cultivadas , Neovascularización Coroidal/metabolismo , Neovascularización Coroidal/patología , Modelos Animales de Enfermedad , Integrina alfa5beta1/biosíntesis , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , ARN/genética , Transducción de Señal
15.
Arch Microbiol ; 202(9): 2551-2556, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32661667

RESUMEN

A Gram-stain positive, motile, aerobic and rod-shaped strain (MIC A30T) was isolated from river sediment in Yuantouzhu park, Wuxi City, China. Growth occurred at 20-40 °C, at pH 6.0-9.0 and at 0-5.0% NaCl. Strain MIC A30T was moderately related to Arthrobacter liuii CGMCC 1.12778T (97.9%), Arthrobacter pokkaliiT (97.9%) and Arthrobacter globiformis NBRC 12137T (96.7%) by 16S rRNA analysis. The DNA-DNA relatedness values between strain MIC A30T and these reference strains were below 30%. The DNA G+C content was 63.1 mol%. Average nucleotide identity (ANI) and genome-to-genome distance (GGD) values between strain MIC A30T and A. liuii CGMCC 1.12778T were 60.34% and 29.39%, respectively. Quinone was identified as MK-9(H2). Major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. Major fatty acids were iso-C15:0, anteiso-C15:0 and anteiso-C17:0. Whole-cell sugars were galactose, mannose and rhamnose. The cell wall peptidoglycan contained A4α peptidoglycan type with lysine as the diagnostic diamino acid. Based on several taxonomic results, strain MIC A30T is identified as a novel species in genus Arthrobacter, whose name is proposed as Arthrobacter sedimenti sp. nov. The type strain is MIC A30T (= KACC 19599T = CGMCC 1.13474T).


Asunto(s)
Arthrobacter/clasificación , Sedimentos Geológicos/microbiología , Microbiología del Suelo , Arthrobacter/química , Arthrobacter/genética , Arthrobacter/aislamiento & purificación , Composición de Base , China , ADN Bacteriano/genética , Hibridación de Ácido Nucleico , Peptidoglicano/química , ARN Ribosómico 16S/genética , Ríos/microbiología , Especificidad de la Especie
16.
Phys Chem Chem Phys ; 22(14): 7483-7488, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-32219228

RESUMEN

Two dimensional atomic crystals with pentagonal building blocks have attracted extensive interest in recent years for their fundamental significance and potential applications in nanoscale devices. Here, with the help of ab initio calculations based on density functional theory, we report a unique pentagonal structured NiS2 monolayer in P4[combining macron]21m symmetry, named P-NiS2. Its dynamic stability has been confirmed by phonon mode analysis. Molecular dynamics simulations and total-energy calculations show that this new P-NiS2 has robust thermal stability and energetically more stable than all other reported NiS2 monolayer structures. Electronic band structure calculations show that it is a semiconductor with an indirect band gap of 1.94 eV. Furthermore, we find that small strain triggers a transition from the indirect to direct band gap for this P-NiS2, suggesting its great potential for applications based on strain-engineering techniques.

17.
Med Sci Monit ; 26: e924811, 2020 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-32719308

RESUMEN

BACKGROUND Contracture is related to modulation of passive stiffness in muscle and tendon after spinal cord injury (SCI). Current clinical assessments of stiffness in muscles and tendons are subjective in patients with spinal cord injury. We proposed a quantitative method to evaluate stiffness of the gastrocnemius and Achilles tendon (AT) with a portable device, the MyotonPRO. The purpose of this study was to investigate the intraoperator and interoperator reliability of the MyotonPRO when used in patients after spinal cord injury. MATERIAL AND METHODS Fourteen patients with SCI participated in this study. Gastrocnemius stiffness and AT stiffness were measured with the MyotonPRO. RESULTS In participants with SCI, the intraclass correlation coefficient (ICC) values for intraoperator and interoperator reliability of stiffness measurements in the gastrocnemius and AT were excellent (all ICC >0.87), with relatively low values for standard error measurement (SEM) and minimal detectable change (MDC). CONCLUSIONS Our findings suggest that use of the MyotonPRO is feasible for evaluating stiffness of the gastrocnemius and AT in the lower limbs of patients with spinal cord injury.


Asunto(s)
Fuerza Muscular/fisiología , Tono Muscular/fisiología , Traumatismos de la Médula Espinal/fisiopatología , Tendón Calcáneo/fisiología , Adolescente , Adulto , Anciano , Articulación del Tobillo/fisiología , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiología , Rango del Movimiento Articular/fisiología , Reproducibilidad de los Resultados
18.
Med Sci Monit ; 26: e926578, 2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33137025

RESUMEN

BACKGROUND Temporomandibular disorders (TMD) are accompanied by masticatory muscle-related pain, making it meaningful to assess the stiffness of the masticatory muscles. The present study investigated the intra- and inter-operator reliabilities of MyotonPRO for assessing the elasticity of masseter muscles, to determine minimal detectable changes, and to quantify changes in stiffness from conditions of relaxation to maximal contraction. MATERIAL AND METHODS Twenty healthy subjects (10 men and 10 women) were recruited. The stiffness of their masseter muscles was quantified with MyotonPRO in both relaxed and maximal contraction conditions. Two experienced operators (A and B) measured stiffness on the same day, and operator A repeated this procedure 5 days later. RESULTS Intra-rater reliability was good (ICC=0.78) and inter-operator reliability was excellent (ICC=0.95) for assessing masseter muscle stiffness with MyotonPRO. The mean stiffness of the masseter muscle on the dominant side was 369.5 N/m under relaxed conditions and 618.3 N/m at maximum bite force, an increase of 67.4%. Stiffness on the dominant and non-dominant sides did not differ significantly under both conditions (P>0.05). CONCLUSIONS MyotonPRO is a reliable method for quantifying the stiffness of the masseter muscle and monitoring its changes under different contraction conditions.


Asunto(s)
Electromiografía , Músculo Masetero/fisiología , Contracción Muscular/fisiología , Adulto , Fuerza de la Mordida , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
19.
Med Sci Monit ; 26: e926407, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33071278

RESUMEN

BACKGROUND Achilles tendinopathy commonly occurs in specific regions of the tendon, and Achilles tendon stiffness can be related to local pathological changes in the tendon. The MyotonPRO is a new handheld device that conveniently assesses stiffness of muscles and tendons. This study aimed to 1) evaluate the intra- and inter-rater reliability of stiffness measurements of the Achilles tendon at different ankle positions, 2) investigate the modulation of stiffness at different ankle joint angles, and 3) examine the differences between 2 regions of Achilles tendon stiffness. MATERIAL AND METHODS Thirty healthy young adults (15 men and 15 women) participated in this study. The regional Achilles tendon stiffness at 0 cm (AT-0) and 6 cm (AT-6) above the tendon insertion were evaluated by the MyotonPRO in the neutral position and 10° dorsiflexion of the ankle joint. Measurements of stiffness were taken by 2 raters on the first day and 5 days later. The stiffness data were compared by repeated measures analysis of variance (ANOVA). RESULTS The intra- and inter-rater reliability of stiffness measurements at AT-0 and AT-6 for each ankle position were good (all intraclass correlation coefficients >0.84). A significant modulation of Achilles tendon stiffness was obtained at different ankle joint angles (P<0.05). Stiffness at AT-0 was higher than at AT-6 (P<0.05) in both positions. CONCLUSIONS These results suggest the MyotonPRO reliably assessed Achilles tendon stiffness and monitors its modulation, and tendon stiffness increased with ankle dorsiflexion. Stiffness was also nonuniform along the length of the tendon.


Asunto(s)
Tendón Calcáneo , Articulación del Tobillo , Músculo Esquelético , Tendón Calcáneo/patología , Tendón Calcáneo/fisiopatología , Adulto , Articulación del Tobillo/patología , Articulación del Tobillo/fisiopatología , Femenino , Humanos , Masculino , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Rango del Movimiento Articular , Tendinopatía/patología , Tendinopatía/fisiopatología
20.
Curr Microbiol ; 77(7): 1341-1347, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32140833

RESUMEN

A Gram-negative, motile, aerobic, and rod-shaped strain (MIC 1.5T) was isolated from soil in Changguangxi national wetland park. Growth occurred at 20-45 °C, at pH 6.0-8.0, and at 0-4.0% NaCl. Based on 16S rRNA gene sequence analysis, strain MIC 1.5T was related to were identified as Luteimonas dalianensis CGMCC 1.12191T (95.3%), Luteimonas padinae DSM 101536T (94.5%), Luteimonas huabeiensis DSM 26429T (94.1%), and Luteimonas mephitis DSM 12574T (92.5%). The DNA-DNA relatedness values between strain MIC 1.5T , and these strains were well below 31%. The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. The DNA G+C content of strain MIC 1.5T was 66.3 mol%. Average nucleotide identity (ANI) and genome-to-genome distance (GGD) values between strain MIC 1.5T and L. dalianensis CGMCC 1.12191T were 65.39% and 29.52%, respectively. The quinone was identified as Q-8. The major fatty acids were iso-C15:0, iso-C15:0 3OH, and iso-C17:0 3OH and summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH). Based on the phylogenetic, physiological, and chemotaxonomic results, strain MIC 1.5T represents a novel species of the genus Luteimonas, for which the name Luteimonas cellulosilyticus sp. nov. is proposed. The type strain is MIC 1.5T (= KACC 19469T = CCTCC AB 2017256T).


Asunto(s)
Xanthomonadaceae , China , Ácidos Grasos , Microbiología del Suelo , Humedales , Xanthomonadaceae/química , Xanthomonadaceae/clasificación , Xanthomonadaceae/genética
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