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1.
Artigo em Zh | MEDLINE | ID: mdl-38311952

RESUMO

Poisoning induced by inhalation of hydrogen chloride has significant effects on the respiratory system. It can cause severe pulmonary edema and acute respiratory distress syndrome (ARDS) in the early stage, and even death in critical cases. As a novel treatment for ARDS, the efficacy of sivelestat sodium in infection-induced ARDS has been widely verified, but its application in ARDS caused by chemical poisoning is still scarce in literature. Here we report a case of ARDS induced by hydrogen chloride inhalation which was successfully treated with sivelestat sodium and conventional treatment.


Assuntos
Glicina , Ácido Clorídrico , Síndrome do Desconforto Respiratório , Sulfonamidas , Humanos , Glicina/análogos & derivados , Ácido Clorídrico/efeitos adversos , Pulmão , Síndrome do Desconforto Respiratório/etiologia , Sódio
2.
J Phys Chem A ; 127(8): 2034-2040, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36791330

RESUMO

We apply the Self-Consistent Effective Hamiltonian Theory (SCEHT), which uses a general variational Fermionic many-body wave function to generate an effective Hamiltonian in a quadratic form, to the Anderson impurity model. The chiral symmetry-breaking quadratic effective Hamiltonian is solved exactly for the single Fermion excitation spectrum. We validate the theory by numerically solving a model problem. The solution shows the correct Kondo resonance in the quasi-particle density of states.

3.
Zhonghua Wai Ke Za Zhi ; 61(2): 120-128, 2023 Feb 01.
Artigo em Zh | MEDLINE | ID: mdl-36720621

RESUMO

Objective: To investigate the clinical effects of one-stage revision combined with intra-articular infusion of vancomycin in the treatment of chronic prosthetic joint infection (PJI) caused by Enterococcal. Methods: From May 2013 to June 2020,the clinical data of 9 patients (2 males and 7 females) with chronic Enterococcal PJI treated with one-stage revision using intra-articular infusion of vancomycin at Department of Orthopaedics,First Affiliated Hospital of Xinjiang Medical University were retrospectively analyzed,including 8 hips and 1 knee.A total of 9 patients with age of (63.9±11.7)years (range:43 to 76 years) were included, and the body mass index was (23.6±4.3)kg/m2 (range:18 to 30 kg/m2).There were 6 cases with antibiotic history and 5 cases with sinus tract.The joint fluid,infected tissue around the prosthesis and ultrasonic shock fluid of the prosthesis were collected during operation for microbial culture identification and drug sensitivity test.After thorough debridement of the infected site and removal of the infected prosthesis,a new prosthesis was implanted,then the drainage tube in the operation area was placed.After surgery,vancomycin(1.0 g,q12 h) was combined with intra-articular vancomycin(0.5 g,qd) in monomicrobial PJI,and vancomycin(1.0 g,q12 h) was combined with intra-articular vancomycin (0.5 g,qd) and imipenem/meropenem (0.5 g,qd),and the interval between the two drugs was 12 hours in polymicrobial PJI.Hip and knee functions were evaluated by Harris Hip Score or Knee Society Score(KSS),respectively.The comparison of hip function scores before and after operation was performed by paired t-test. Results: All patients were followed up for (60±39)months(range:24 to 110 months).Two cases were infected with Enterococcus faecium and 7 cases were infected with Enterococcus faecalis.There were 7 cases of monomicrobial infection and 2 cases of polymicrobial infection.Erythromycin(5/9),tetracycline(4/9),ciprofloxacin and ß-lactam antibiotics(3/9) were the top three antibiotics in Enterococci resistance rate.The sensitive antibiotics for Enterococcal were vancomycin,linezolid and tigecycline.The average duration of intravenous antibiotics was (14±1)days (range:13 to 17 days),and the average duration of antibiotics in articular cavity was (15±2)days(range:11 to 20 days).Mean duration of oral antibiotic use after discharge was (2±1)months(range:1 to 3 months).One case of polymicrobial PJI treatment failed,with a failure rate of 1/9.At last follow-up,the Harris score of patients with hip PJI increased from (43±6)points to (84±6)points(t=-11.899, P<0.01). KSS score of knee function was improved from 33 point pre-operatively to 85 point post-operatively;overall function score was improved from 35 point pre-operatively to 80 point post-operatively.During the treatment,no formation of sinus tract of the hip joint caused by a catheter,skin necrosis at the knee puncture site or leakage of joint fluid;no complications such as deep vein thrombosis and pulmonary embolism occurred. Conclusions: One-stage revision combined with intra-articular infusion of vancomycin can achieve acceptable infection control rate and joint function in patients with chronic Enterococcus PJI.However,the treatment of polymicrobial PJI still needs to be further verified.


Assuntos
Antibacterianos , Vancomicina , Feminino , Masculino , Humanos , Vancomicina/uso terapêutico , Estudos Retrospectivos , Antibacterianos/uso terapêutico , Enterococcus , Próteses e Implantes , Inflamação
4.
J Water Health ; 20(4): 610-619, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35482378

RESUMO

The objective of this study was to understand the drinking water quality state in the Inner Mongolia Autonomous Region from 2014 to 2018 and to derive information that will provide a basis for improving the drinking water quality in the region. Monitoring data for drinking water from the Inner Mongolia Autonomous Region for 2014 to 2018 were analyzed and the results were compared with GB 5749-2006, the Standard Test Method for Drinking Water, and GB 5749-2006, the Drinking Water Quality Standards. Data for a total of 30,613 water samples were assessed. Of the data for the microbiological index, sensory trait and general chemical index, and toxicological index, 89, 80, and 69% were qualified, respectively. For the toxicological index, the fluoride and nitrate nitrogen data were the least compliant. The water quality in all the cities was generally very suitable for drinking. However, there were marked differences in the qualified rates of drinking water in different areas and the qualified rates of the data for the three indexes were lower in rural areas than in urban areas. Given the varied issues with the drinking water quality, the relevant departments of League cities should implement appropriate and effective treatment measures to improve the drinking water quality and ensure it is safe for residents.


Assuntos
Água Potável , Qualidade da Água , China , Fluoretos , Abastecimento de Água
5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 50(3): 257-262, 2022 Mar 24.
Artigo em Zh | MEDLINE | ID: mdl-35340144

RESUMO

Objective: To analyze the safety and efficacy of combined left atrial appendage (LAA) and patent foramen ovale (PFO) closure in adult atrial fibrillation (AF) patients complicating with PFO. Methods: This study is a retrospective and cross-sectional study. Seven patients with AF complicated with PFO diagnosed by transesophageal echocardiography (TEE) in Zhoupu Hospital Affiliated to Shanghai University of Medicine & Health Sciences from June 2017 to October 2020 were selected. Basic data such as age, gender and medical history were collected. The atrial septal defect or PFO occluder and LAA occluder were selected according to the size of PFO, the ostia width and depth of LAA. Four patients underwent left atrial appendage closure(LAAC) and PFO closure at the same time. PFO closure was performed during a one-stop procedure of cryoablation combined with LAAC in 2 patients. One patient underwent PFO closure at 10 weeks after one-stop procedure because of recurrent transient ischemic attack (TIA). All patients continued to take oral anticoagulants. TEE was repeated 8-12 weeks after intervention. In case of device related thrombus(DRT), TEE shall be rechecked 6 months after adjusting anticoagulant and antiplatelet drug treatment. Patients were follow-up at 1, 3, 6, 12, 24 months by telephone call, and the occurrence of cardio-cerebrovascular events was recorded. Results: Among the 7 patients with AF, 2 were male, aged (68.0±9.4) years, and 3 had a history of recurrent cerebral infarction and TIA. Average PFO diameter was (3.5±0.8)mm. Three patients were implanted with Watchman LAA occluder (30, 30, 33 mm) and atrial septal defect occluder (8, 9, 16 mm). 2 patients were implanted with LAmbre LAA occluder (34/38, 18/32 mm) and PFO occluder (PF1825, PF2525). 2 patients were implanted with LACbes LAA occluder (24, 28 mm) and PFO occluder (PF2525, PF1825) respectively. The patients were followed up for 12 (11, 24) months after operation. TEE reexamination showed that the position of LAA occluder and atrial septal defect occluder or PFO occluder was normal in all patients. DRT was detected in 1 patient, and anticoagulant therapy was adjusted in this patient. 6 months later, TEE showed that DRT disappeared. No cardiovascular and cerebrovascular events occurred in all patients with AF during follow-up. Conclusions: In AF patients complicated with PFO, LAAC combined with PFO closure may have good safety and effectiveness.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Forame Oval Patente , Adulto , Idoso , Apêndice Atrial/cirurgia , Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia , Cateterismo Cardíaco/métodos , China , Estudos Transversais , Forame Oval Patente/complicações , Forame Oval Patente/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Artigo em Zh | MEDLINE | ID: mdl-35915951

RESUMO

In our country, there are a large number of carbon monoxide poisoning patients every winter. 10% to 30% of patients with acute carbon monoxide poisoning develop acute carbon monoxide poisoning delayed encephalopathy after a "false recovery period" of about 2 to 60 days. The morbidity and mortality rates of the disease are extremely high, but there is still no effective treatment for this condition. The pathogenesis of the disease is complex, and there is no clear conclusion yet. After consulting a large number of recent relevant literatures, this article reviews the main research results of the pathogenesis of the disease so far, with an aim to facilitate its early clinical diagnosis and correct treatment.


Assuntos
Encefalopatias , Intoxicação por Monóxido de Carbono , Encefalopatias/etiologia , Intoxicação por Monóxido de Carbono/complicações , Intoxicação por Monóxido de Carbono/terapia , Humanos
7.
Artigo em Zh | MEDLINE | ID: mdl-35255579

RESUMO

Objective: To systematically evaluate the correlation between professional quality of life and social support of Chinese nurses based on Pearson and Spearman correlation coefficients. Methods: In databases including PubMed, Cochrane Library, CINAHL, Medline, CBM, CNKI、Wanfang, and other databases were searched by computer for the literatures on correlation between Chinese nurses' professional quality of life and social support from January 2005 to July 2020. The Chinese and English search terms are "nurse" "professional quality of life" "empathy satisfaction" "empathy fatigue" "professional quality of life" "ProQOL" "comparison satisfaction" "comparison fatigue" "social support" "competent social support" "SSRS" "PSSS", etc. Literatures were screened according to the inclusion and exclusion criteria. After evaluating quality and extracting data, meta-analysis was conducted using RevMan 5.3 software. Results: A total of 12 studies were included. The meta analysis showed that nurses' compassion satisfaction, burnout, secondary traumatic stress were related to social support, summary r were 0.35, -0.26 and -0.23 respectively. The correlation between compassion satisfaction and social support were increased with sample, the south was higher than the north, and comprehensive departments were higher than other departments (P<0.05) . The correlation between burnout and social support were increased with time and sample, and the south was higher than the north, oncology was higher than others, non-random sampling was higher than random sampling, using ProQOL and Perceived Social Support Scale (PSSS) was higher than Professional Quality of Life Scale (ProQOL) and Social Support Racting Scale (SSRS) (P<0.05) . The correlation coefficient between secondary traumatic stress and social support in oncology was higher than others, random sampling was higher than non-random sampling, using ProQOL and PSSS was higher than ProQOL and SSRS (P<0.05) . Conclusion: There is a positive and weak correlation between compassion satisfaction and social support, and a negative and weak correlation between burnout and secondary traumatic stress and social support. There are differences in different time, research design, region and department.


Assuntos
Esgotamento Profissional , Enfermeiras e Enfermeiros , China , Estudos Transversais , Humanos , Satisfação no Emprego , Qualidade de Vida , Apoio Social , Inquéritos e Questionários
8.
Zhonghua Wai Ke Za Zhi ; 59(6): 484-490, 2021 Jun 01.
Artigo em Zh | MEDLINE | ID: mdl-34102732

RESUMO

Objective: To analyze the pathogen distribution and drug resistance in acute,delayed and chronic periprosthetic joint infection (PJI). Methods: The clinical data of 316 patients with periprosthetic infection after primary hip and knee arthroplasty admitted to the Department of Arthroplasty,the First Affiliated Hospital,Xinjiang Medical University from August 2010 to August 2020 were retrospectively analyzed.There were 146 males and 170 females,aged (62.3±14.2) years (range:22 to 89 years).One hundred and sixty one patients underwent total hip arthroplasty and 155 patients underwent total knee arthroplasty.According to the time of postoperative infection,the patients were divided into acute PJI group (65 cases),delayed PJI group (83 cases) and chronic PJI group (168 cases).The results of pathogen species,composition ratio and drug susceptibility tests were collected,and the independent sample t test,Chi-square test or Fisher's exact probability test were used for comparison. Results: Gram-positive bacteria were the main pathogens of PJI (49.7%,157/316),and the positive rates of culture in patients with acute PJI,delayed PJI and chronic PJI were 33.8% (22/65),55.4% (46/83) and 53.0% (89/168),and the difference was statistically significant(χ²=8.343,P=0.015).The common bacteria were coagulase-negative Staphylococcus (54.8%,86/157) and Staphylococcus aureus (30.6%,48/157),The drug-sensitivity to linezolid,vancomycin and tigacycline was 100%.The gram-negative bacteria were mainly Escherichia coli and Enterobacter cloacae,and the drug resistance rate to carbapenems was low,ranging from 0 to 9.09%.The drug resistance rates of acute PJI patients to rifampicin,ciprofloxacin and erythromycin were significantly higher than those of late onset and chronic PJI patients,the difference was statistically significant(rifampicin:χ²=14.332,P=0.001;ciprofloxacin:χ²=12.086,P=0.002;erythromycin:χ²=9.096,P=0.010);The drug resistance rate of acute PJI patients to levofloxacin,clindamycin and tetracycline was higher than that of chronic PJI patients,and the difference was statistically significant(levofloxacin:χ²=10.500,P=0.002; clindamycin: χ²=7.103,P=0.007; tetracycline: χ²=6.909,P =0.012).The resistance rate of ampicillin/sulbactam in acute PJI (60.0%) was significantly higher than that in chronic PJI (16.7%),and the difference was statistically significant(χ²= 5.853,P=0.040). Conclusion: Gram-positive bacteria are the main pathogens of PJI,and the resistance rate of pathogens of acute PJI is higher than that of late onset and chronic PJI.


Assuntos
Artroplastia de Quadril , Infecções Relacionadas à Prótese , Antibacterianos/uso terapêutico , Artroplastia de Quadril/efeitos adversos , Farmacorresistência Bacteriana , Feminino , Bactérias Gram-Positivas , Humanos , Masculino , Testes de Sensibilidade Microbiana , Infecções Relacionadas à Prótese/tratamento farmacológico , Estudos Retrospectivos
9.
Zhonghua Bing Li Xue Za Zhi ; 49(7): 721-726, 2020 Jul 08.
Artigo em Zh | MEDLINE | ID: mdl-32610385

RESUMO

Objective: To study the clinicopathological characteristics and pathologic diagnosis of autoimmune gastritis. Methods: Fourteen biopsies of autoimmune gastritis were collected from January 2018 to March 2019 at Guangdong Provincial People's Hospital. Their clinical data, histological features and immunohistochemical (IHC) results were analyzed, with review of relevant literature. Results: All 14 patients' ages ranged from 41 to 79 years (mean 55 years). There were 12 females and 2 males. All patients had non-specific symptoms, but they all had positive serum anti-parietal cell antibody and/or anti-intrinsic factor antibody. Seven patients had variable degree of anemia. Two patients had concomitant H. pylori infection. Two patients presented with multiple protruding polyps in corpus/fundus, 0.2 to 0.9 cm in diameter, or multiple large lobulated and broad based polyps (0.8 to 3.5 cm in diameters). The former cases were diagnosed as type 1 neuroendocrine tumors, the latter were multiple hyperplastic polyps. Microscopically, autoimmune gastritis showed typical morphology, characterized by diffuse corpus-restricted atrophic gastritis with variable proportions of intestinal metaplasia, or pseudopyloric metaplasia, pancreatic, acinar metaplasia, foveolar hyperplasia and hyperplasia of the endocrine-like cells (ECL cells). Hyperplasia of ECL cells often needed IHC staining to confirm. CgA/Syn IHC stain highlighted linear and micronodular ECL cell hyperplasia. In the absence of concurrent or past H. pylori infection, the antrum was usually normal. Gastrin IHC stain showed hyperplasia of gastrin-producing cells (G cells) in the antrum. Two cases were in the early phase, six were in florid phase, and six were end phase. Conclusions: Most patients of autoimmune gastritis have non-specific symptoms or are asymptomatic and show various endoscopic findings. There are three histologic phases of autoimmune gastritis. Recognition of this entity would be beneficial for pathologists to avoid misdiagnosis. Pathologists can make preferred diagnosis of autoimmune gastritis depending on the histologic clues and prompt appropriate and timely management for the patients.


Assuntos
Doenças Autoimunes , Gastrite , Adulto , Idoso , Celulas Tipo Enterocromafim , Feminino , Mucosa Gástrica , Infecções por Helicobacter , Helicobacter pylori , Humanos , Masculino , Pessoa de Meia-Idade
10.
Zhonghua Wai Ke Za Zhi ; 58(6): 464-468, 2020 Jun 01.
Artigo em Zh | MEDLINE | ID: mdl-32498487

RESUMO

Objective: To investigate the diagnose value of D-dimer for chronic periprosthetic infection (PJI) after hip and knee arthroplasty. Methods: A retrospective analyze was conducted on 168 patients underwent revision arthroplasty and primary arthroplasty at the First Affiliated Hospital of Xinjiang Medical University from November 2017 to December 2018.There were 58 males and 110 females, aged(58.6±14.5)years.There were 48 cases of chronic PJI (21 cases of knee joint, 27 cases of hip joint), 57 cases of aseptic loosening (16 cases of knee joint, 41 cases of hip joint), and 63 cases of normal follow-up patients after hip (35 cases) or knee (28 cases) arthroplasty.The levels of D-dimer, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were collected.The levels of D-dimer in patients with chronic PJI of hip and knee joints were compared by Mann-Whitney U test.The diagnostic efficacy of D-dimer, ESR and CRP in chronic PJI of hip and knee joints was analyzed by receiver operator curve (ROC). Results: The D-dimer level was significantly higher in knee chronic PJI patients than hip chronic PJI patients(M (Q(R)) ) (1 040 (1 140.5) µg/L vs.435 (605) µg/L, Z=3.169, P=0.002) . ROC analysis showed that the optimum cutoff value of D-dimer in the diagnosis of chronic PJI was 370.5 µg/L, the sensitivity was 90.5%, the specificity was 84.1%; the optimum cutoff value of CRP was 9.3 mg/L, the sensitivity was 95.2%, the specificity was 90.9%, the optimum cutoff value of ESR was 33 mm/h, the sensitivity was 90.5%, and the specificity was 88.6%.The optimum cutoff value of D-dimer in the diagnosis of chronic PJI of hip joint is 294 µg/L, the sensitivity of diagnosis is 66.7%, the specificity is 77.6%; the optimum cutoff value of ESR is 45 mm/h, the sensitivity of diagnosis is 55.6% , the specificity is 97.4%; the optimum cutoff value of CRP is 8.1 mg/L, the sensitivity of diagnosis is 74.1%, the specificity is 84.2%. Conclusion: The value of D-dimer in the diagnosis of chronic PJI of knee joint is higher than that of hip joint, but the value of D-dimer in the diagnosis of chronic PJI is not better than ESR and CRP.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Infecções Relacionadas à Prótese/diagnóstico , Adulto , Idoso , Biomarcadores/sangue , Sedimentação Sanguínea , Proteína C-Reativa/análise , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/sangue , Infecções Relacionadas à Prótese/etiologia , Estudos Retrospectivos
11.
Nano Lett ; 18(12): 7777-7783, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30499678

RESUMO

The promise of magnetic skyrmions in future spintronic devices hinges on their topologically enhanced stability and the ability to be manipulated by external fields. The technological advantages of nonvolatile zero-field skyrmion lattice (SkL) are significant if their stability and reliability can be demonstrated over a broad temperature range. Here, we study the relaxation dynamics including the evolution and lifetime of zero-field skyrmions generated from field cooling (FC) in an FeGe single-crystal plate via in situ Lorentz transmission electron microscopy (L-TEM). Three types of dynamic switching between zero-field skyrmions and stripes are identified and distinguished. Moreover, the generation and annihilation of these metastable skyrmions can be tailored during and after FC by varying the magnetic fields and the temperature. This dynamic relaxation behavior under the external fields provides a new understanding of zero-field skyrmions for their stability and reliability in spintronic applications and also raises new questions for theoretical models of skyrmion systems.

12.
Persoonia ; 43: 186-221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32214500

RESUMO

The Fusarium incarnatum-equiseti species complex (FIESC) is a phylogenetically species-rich complex that includes over 30 cryptic phylogenetic species, making identification based on phenotypic characters problematic. Several established Fusarium species known to reside in the FIESC lack type material, further complicating the use of Latin binomials for this complex. To overcome this problem, an informal classification system based on a haplotype nomenclature was introduced to improve communication between researchers in various fields. However, some conflicts in the application of this nomenclature system have arisen. To date, 16 phylo-species in the FIESC have been provided with Latin binomials with approximately 18 FIESC phylo-species still lacking Latin binomials, the majority of which reside in the Incarnatum clade. The aim of this study is to introduce Latin binomials for the unnamed FIESC phylo-species based on phylogenetic inference supported by phenotypic characters. The three-gene (calmodulin, RNA polymerase II second largest subunit and translations elongation factor 1-alpha) phylogenetic inference resolved 47 lineages, of which 44 belonged to the FIESC. The F. camptoceras species complex (FCAMSC) is introduced here for three lineages that are distinct from the FIESC. Epitypes are designated for F. compactum, F. incarnatum and F. scirpi, and a neotype for F. camptoceras. Latin binomials are provided for 20 of these newly resolved phylo-species in the FIESC.

13.
Phys Rev Lett ; 121(17): 176801, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30411944

RESUMO

We report a method to control contributions of bulk and surface states in the topological insulator Bi_{2}Te_{2}Se that allows accessing the spin-polarized transport endowed by topological surface states. An intrinsic surface dominant transport is established when cooling the sample to low temperature or reducing the conduction channel length, both achieved in situ in the transport measurements with a four-probe scanning tunneling microscope without the need of further tailoring the sample. The topological surface states show characteristic transport behaviors with mobility about an order of magnitude higher than reported before, and a spin polarization approaching the theoretically predicted value. Our result demonstrates accessibility to the intrinsic high mobility spin transport of topological surface states, which paves a way to realizing topological spintronic devices.

14.
Proc Natl Acad Sci U S A ; 112(31): 9558-62, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26195791

RESUMO

The interesting transport and magnetic properties in manganites depend sensitively on the nucleation and growth of electronic phase-separated domains. By fabricating antidot arrays in La0.325Pr0.3Ca0.375MnO3 (LPCMO) epitaxial thin films, we create ordered arrays of micrometer-sized ferromagnetic metallic (FMM) rings in the LPCMO films that lead to dramatically increased metal-insulator transition temperatures and reduced resistances. The FMM rings emerge from the edges of the antidots where the lattice symmetry is broken. Based on our Monte Carlo simulation, these FMM rings assist the nucleation and growth of FMM phase domains increasing the metal-insulator transition with decreasing temperature or increasing magnetic field. This study points to a way in which electronic phase separation in manganites can be artificially controlled without changing chemical composition or applying external field.

15.
Nano Lett ; 17(11): 7075-7079, 2017 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-28990787

RESUMO

Magnetic skyrmions, particular those without the support of external magnetic fields over a wide temperature region, are promising as alternative spintronic units to overcome the fundamental size limitation of conventional magnetic bits. In this study, we use in situ Lorentz microscope to directly demonstrate the generation and sustainability of robust biskyrmion lattice at zero magnetic field over a wide temperature range of 16-338 K in MnNiGa alloy. This procedure includes a simple field-cooling manipulation from 360 K (higher than Curie temperature TC ∼ 350 K), where topological transition easily occurs by adapting the short-range magnetic clusters under a certain magnetic field. The biskyrmion phase is favored upon cooling below TC. Once they are generated, the robust high-density biskyrmions persist even after removing the external magnetic field due to the topological protection and the increased energy barrier.

16.
Fa Yi Xue Za Zhi ; 34(6): 590-594, 2018 Jun.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-30896094

RESUMO

OBJECTIVES: To develop a method to screen and quantify 10 common herbicides (paraquat, diquat, glyphosate, glufosinate, cyanazine, atrazine, metazachlor, acetochlor, chlorsulfuron, and metsulfuron) in blood. METHODS: With acetonitrile-water solution [V(acetonitrile)∶V(water)=3∶1] as protein precipitant, 10 common herbicides in blood were detected using ultra-high performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). RESULTS: All the 10 herbicides had good linearity in their linear range (coefficient of determination R2≥0.993), with the recovery rates 67.4%-111.9%, the relative standard deviations 1.5%-10.8%, the accuracies 85.1%-106.1%, intra-day precisions 2.7%-13.5%, and inter-day precisions 3.3%-13.3%. CONCLUSIONS: This method is easy to operate with high recovery rates. It enables rapid and accurate qualitative screening and quantitative analysis of various herbicides in blood simultaneously.


Assuntos
Herbicidas , Cromatografia Líquida de Alta Pressão , Herbicidas/sangue , Espectrometria de Massas , Espectrometria de Massas em Tandem
17.
Artigo em Zh | MEDLINE | ID: mdl-29996377

RESUMO

Objective: To investigate the anti-inflammatory effect of hesperetin (HSP) on lung damage induced by paraquat (PQ) in rats by detecting the levels of inflammatory makers in rat lung tissues. Methods: 140 Wistar male rats were randomly divided into negative control group, HSP control group, HSP control group, paraquat model group, pirfenidone (PDF) positive control group, and 100, 200, 400 mg/kg HSP treatment groups. All groups were exposed to 50mg/kg paraquat by oral gavage except for the negative control group and HSP control group. After 24 hours, the rats in each group were given drug intervention once daily. 10 rats were randomly sacrificed at 7th day and 28th day after exposure to paraquat respectively. 3 rats were randomly selected from them and HE, Masson staining were used to observe the pathological changes in the lungs of each group. Each group randomly selected 6 rats at two time points to detect the levels of TGF-ß(1), TNF-α, IL-4, IL-10, IL-1ß and IFN-γ in rat lung tissues. Results: Histopathological examination found that the lung injury were reduced in the rats of PDF positive control group and all HSP treatment groups. Compared with the negative control group, the levels of TGF-ß1, IL-1ß, TNF-α, IL-4, and IL-10 in rat lung tissues were significantly increased (P<0.05, P<0.01) after PQ exposure at two points in time, and there was no significant difference in the level of IFN-γ in lung tissues compared with the negative control group (P>0.05) . The levels of TGF-ß1, IL-1ß, IL-4, IL-10 and TNF-α in the lung tissues of rats on the 7th day in different dose treatment groups of HSP were reduced compared with those in the PQ model group with varying degrees (P<0.05, P<0.01) . The level of IFN-γ in lung tissues of rats were not significantly different from that of model group (P>0.05) . The levels of TGF-ß(1) and TNF-α in lung tissue of rats on the 28th day in PDF positive control group and different dose treatment groups of HSP were reduced compared with those in the PQ model group with varying degrees (P<0.05, P<0.01). The levels of IFN-γ in the rat lung tissues were increased compared with those in the PQ model group (P<0.05). Besides, there were no significant in the levels of IL-1ß, IL-4 and IL-10 in lung tissues compared with PQ model group (P>0.05). Conclusion: HSP can reduce lung damage induced by PQ in rats by inhibiting the release of inflammatory factors and promoting the secretion of anti-inflammatory factors.


Assuntos
Hesperidina/farmacologia , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico , Pulmão/patologia , Paraquat/toxicidade , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Ratos Wistar
18.
Phys Rev Lett ; 119(10): 105501, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28949192

RESUMO

A defect's formation energy is a key theoretical quantity that allows the calculation of equilibrium defect concentrations in solids and aids in the identification of defects that control the properties of materials and device performance, efficiency, and reliability. The theory of formation energies is rigorous only for neutral defects, but the Coulomb potentials of charged defects require additional ad hoc numerical procedures. Here we invoke statistical mechanics to derive a revised theory of charged-defect formation energies, which eliminates the need for ad hoc numerical procedures. Calculations become straightforward and transparent. We present calculations demonstrating the significance of the revised theory for defect formation energies and thermodynamic transition levels.

19.
Phys Rev Lett ; 119(13): 137202, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-29341679

RESUMO

We demonstrate a new method for the detection of the spin-chemical potential in topological insulators using spin-polarized four-probe scanning tunneling microscopy on in situ cleaved Bi_{2}Te_{2}Se surfaces. Two-dimensional (2D) surface and 3D bulk conductions are separated quantitatively via variable probe-spacing measurements, enabling the isolation of the nonvanishing spin-dependent electrochemical potential from the Ohmic contribution. This component is identified as the spin-chemical potential arising from the 2D charge current through the spin momentum locked topological surface states (TSS). This method provides a direct measurement of spin current generation efficiency and opens a new avenue to access the intrinsic spin transport associated with pristine TSS.

20.
Andrologia ; 49(9)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28295478

RESUMO

To investigate the effects of different concentrations of various cryoprotectants (CPs) on the cell viability as well as expression of spermatogenesis-related genes, such as CREM, Stra8 and HSP70-2 in frozen-thawed bovine calf testicular tissue, immature bovine (Qinchuan cattle) calf testicular tissue was collected and cryopreserved in the cryomedia containing different concentrations (5%, 10%, 15% and 20%) of the following three CPs: glycerol, ethylene glycol (EG) and dimethyl sulphoxide (DMSO) respectively. After 1 month cryopreservation in liquid nitrogen, cell viability was evaluated using Trypan blue exclusion under a bright-field microscope. The mRNA expression of the three genes was also evaluated using qRT-PCR. The results indicated that different concentrations of glycerol, EG and DMSO in cryomedia during cryopreservation could protect bovine calf testicular tissue in various ways to avoid freezing or cryopreservation-induced expression changes in spermatogenesis-related genes. The highest cell viability and the three spermatogenesis-related genes (CREM, Stra8 and HSP70-2) expression level came from the cryomedia containing glycerol, EG and DMSO at 10% concentration respectively (p < .05). Meanwhile, compared with the other CPs, the frozen-thawed bovine calf testicular tissue treated with 10% DMSO exhibited the highest cell viability and mRNA expression level of the spermatogenesis-related genes (CREM, Stra8 and HSP70-2).


Assuntos
Bovinos , Criopreservação , Crioprotetores/administração & dosagem , Testículo , Animais , Sobrevivência Celular , Modulador de Elemento de Resposta do AMP Cíclico/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Masculino
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