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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(11): 1174-1183, 2021 Nov 15.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-34753551

RESUMO

OBJECTIVES: To study the effect of high-fat diet for maternal Sprague-Dawley rats at different stages on glucose and lipid metabolism in offspring and related mechanisms. METHODS: According to the diet before pregnancy and during pregnancy and lactation, maternal rats were randomly divided into four groups (n=9 each): CC (control diet before pregnancy and during pregnancy and lactation), HC (high-fat diet before pregnancy and control diet during pregnancy and lactation), CH (control diet before pregnancy and high-fat diet during pregnancy and lactation), and HH (high-fat diet before pregnancy and during pregnancy and lactation), and all offspring rats were given control diet after weaning. The body weight of maternal rats was recorded before and during pregnancy. Male offspring rats were selected from each group at the juvenile stage (3-week old) and the adult stage (12-week old) to measure the levels of fasting blood glucose (FBG) and fasting insulin (FINS) and the levels of triglyceride (TG) and total cholesterol (TC) in the liver. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) index was calculated, and the area under the curve (AUC) was calculated for glucose tolerance test (GTT) and insulin tolerance test (ITT). Lipid deposition in the liver was observed, and the mRNA and protein expression levels of the key genes in glucose and lipid metabolism (IR, IRS, and AKT), FASN, SREBP1c, and PPARα in the liver were also measured. RESULTS: Compared with the control diet groups (CC and CH groups), the groups with high-fat diet before pregnancy (HC and HH groups) had a significant increase in body weight (P<0.001). Compared with the CC group, the HC, CH, and HH groups had a significantly greater increase in body weight (P<0.001). Compared with the CC group, the HC, CH, and HH groups had significant increases in body weight, the levels of TG and TC in the liver, and the mRNA and protein expression levels of FASN, SREBP1c, and PPARα in the offspring rats at week 3 after birth (P<0.05), as well as a significant increase in lipid deposition in the liver, with the most significant increase of the parameters in the HH group. Compared with the CC group, the HH group had significant increases in the levels of FBG and FINS, HOMA-IR index, GTT-AUC, ITT-AUC, and the protein expression level of p-IRS in the liver and significant reductions in the mRNA and protein expression levels of IR and IRS in the liver in the offspring rats at week 3 after birth (P<0.05). Compared with the CC group, the HC, CH, and HH groups had significant increases in body weight, the levels of FBG and FINS, HOMA-IR index, GTT-AUC, ITT-AUC, the levels of TG and TC in the liver, protein expression level of p-IRS in the liver, and the mRNA and protein expression levels of FASN, SREBP1c, and PPARα in the offspring rats at week 12 after birth (P<0.05), as well as a significant increase in lipid deposition in the liver, with the most increase of the parameters in the HH group. Compared with the CC group, the HC, CH, and HH groups had significant reductions in the mRNA expression levels of IR, IRS, and AKT and the protein expression levels of IR, IRS, and p-AKT in the offspring rats at week 12 after birth (P<0.05). There were no significant differences in the levels of glucose and lipid metabolism between the HC and CH groups at various stages (P>0.05). CONCLUSIONS: High-fat diet for rats at different stages before and after pregnancy has different effects on glucose and lipid metabolism of offspring rats, and high-fat diet before pregnancy and during pregnancy and lactation has the greatest effect. The effect of high-fat diet on glucose and lipid metabolism of offspring rats is considered associated with the changes in the expression of genes involved in glucose and lipid metabolism.


Assuntos
Dieta Hiperlipídica , Glucose , Resistência à Insulina , Metabolismo dos Lipídeos , Animais , Peso Corporal , Dieta Hiperlipídica/efeitos adversos , Feminino , Glucose/metabolismo , Insulina , Fígado/metabolismo , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley
2.
Biomed Environ Sci ; 31(3): 208-214, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29673443

RESUMO

OBJECTIVE: To detect Japanese encephalitis virus (JEV) rapidly and distinguish its genotypes, a TaqMan-based reverse transcriptase quantitative polymerase chain reaction (RT-PCR) detection system was developed. METHODS: By aligning the full-length sequences of JEV (G1-G5), six sets of highly specific TaqMan real-time RT-PCR primers and probes were designed based on the highly conserved NS1, NS2, and M genes of JEV, which included one set for non-specific JEV detection and five sets for the detection of specific JEV genotypes. Twenty batches of mosquito samples were used to evaluate our quantitative PCR assay. RESULTS: With the specific assay, no other flavivirus were detected. The lower limits of detection of the system were 1 pfu/mL for JEV titers and 100 RNA copies/µL. The coefficients of variation of this real-time RT-PCR were all < 2.8%. The amplification efficiency of this method was between 90% and 103%. CONCLUSION: A TaqMan real-time RT-PCR detection system was successfully established to detect and differentiate all five JEV genotypes.


Assuntos
Culicidae/virologia , Vírus da Encefalite Japonesa (Espécie)/genética , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Animais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Biomed Environ Sci ; 31(3): 227-232, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29673445

RESUMO

Japanese encephalitis (JE) is a serious public health issue. This study was undertaken to better understand the relationship between JE distribution and environmental factors in China. JE data from 2005 to 2010 were retrieved from National Notifiable Disease Report System. ArcGIS, remote sensing techniques, and R software was used to exhibit and explore the relationship between JE distribution and environmental factors. Our results indicated that JE cases were mostly concentrated in warm-temperate, semitropical and tropical zones with annual precipitation > 400 mm; Broad-leaved evergreen forest, shrubs, paddy field, irrigated land, dryland, evergreen coniferous forest, and shrubland were risk factors for JE occurrence, and the former five were risk factors for counties with high JE incidence. These findings will inform the effective allocation of limited health resources such as intensive vaccination, surveillance and training in areas with high environmental risk factors.


Assuntos
Encefalite Japonesa/epidemiologia , Meio Ambiente , Monitoramento Epidemiológico , China/epidemiologia , Encefalite Japonesa/virologia , Humanos , Incidência , Fatores de Risco
4.
Appl Environ Microbiol ; 83(4)2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27986717

RESUMO

Manipulation of biofilm formation in Shewanella is beneficial for application to industrial and environmental biotechnology. BpfA is an adhesin largely responsible for biofilm formation in many Shewanella species. However, the mechanism underlying BpfA production and the resulting biofilm remains vaguely understood. We previously described the finding that BpfA expression is enhanced by DosD, an oxygen-stimulated diguanylate cyclase, under aerobic growth. In the present work, we identify FlrA as a critical transcription regulator of the bpfA operon in Shewanella putrefaciens CN32 by transposon mutagenesis. FlrA acted as a repressor of the operon promoter by binding to two boxes overlapping the -10 and -35 sites recognized by σ70 DosD regulation of the expression of the bpfA operon was mediated by FlrA, and cyclic diguanylic acid (c-di-GMP) abolished FlrA binding to the operon promoter. We also demonstrate that FlhG, an accessory protein for flagellum synthesis, antagonized FlrA repression of the expression of the bpfA operon. Collectively, this work demonstrates that FlrA acts as a central mediator in the signaling pathway from c-di-GMP to BpfA-associated biofilm formation in S. putrefaciens CN32. IMPORTANCE: Motility and biofilm are mutually exclusive lifestyles, shifts between which are under the strict regulation of bacteria attempting to adapt to the fluctuation of diverse environmental conditions. The FlrA protein in many bacteria is known to control motility as a master regulator of flagellum synthesis. This work elucidates its effect on biofilm formation by controlling the expression of the adhesin BpfA in S. putrefaciens CN32 in response to c-di-GMP. Therefore, FlrA plays a dual role in controlling motility and biofilm formation in S. putrefaciens CN32. The cooccurrence of flrA, bpfA, and the FlrA box in the promoter region of the bpfA operon in diverse Shewanella strains suggests that bpfA is a common mechanism that controls biofilm formation in this bacterial species.


Assuntos
Adesinas Bacterianas/genética , Biofilmes/crescimento & desenvolvimento , Proteínas Repressoras/genética , Shewanella putrefaciens/metabolismo , Transcrição Gênica/genética , Adesinas Bacterianas/metabolismo , Proteínas de Bactérias/genética , Sequência de Bases , GMP Cíclico/análogos & derivados , GMP Cíclico/farmacologia , Flagelos/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Regiões Promotoras Genéticas/genética , Shewanella putrefaciens/genética
5.
Biomed Environ Sci ; 30(3): 210-214, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28427491

RESUMO

In this study, we isolated a virus strain (YN12031) from specimens of Armigeres subalbatus collected in the China-Laos border. BHK-21 cells infected with YN12031 exhibited an evident cytopathic effect (CPE) 32 h post-infection. The virus particles were spherical, 70 nm in diameter, and enveloped; they also featured surface fibers. Molecular genetic analysis revealed that YN12031 was closely related to alpha viruses such as Chikungunya virus and Sindbis virus, and located in the same clade as MM2021, the prototype of Getahvirus (GETV) isolated in Malaysia in 1955. Phylogenetic analysis of the E2 and capsid genes further revealed that YN12031 was located in the same clade as the Russian isolate LEIV/16275/Mag. Analysis of the homology of nucleotides and amino acids in the coding area and E2 gene demonstrated that the YN12031 isolated from the China-Laos border (tropical region) was related closest to the LEIV/16275/Mag isolate obtained in Russia (North frigid zone area) among other isolates studied. These results suggest that GETV can adapt to different geographical environments to propagate and evolve. Thus, strengthening the detection and monitoring of GETV and its related diseases is very crucial.


Assuntos
Alphavirus/genética , Alphavirus/isolamento & purificação , Culicidae/virologia , Animais , Linhagem Celular , China , Cricetinae , Laos , Filogenia
6.
Biomed Environ Sci ; 29(12): 902-908, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28081752

RESUMO

Fifteen pediatric cases of suspected Japanese encephalitis (JE) were reported in Beijing Children's Hospital during the late summer of 2013. The clinical manifestations in most cases included high fever, seizures, and abnormal magnetic resonance imaging findings. Twelve of 15 cases were laboratory-confirmed as JE cases by pathogen identification. Epidemiological investigations showed that five of the 12 laboratory-confirmed patients had an incomplete JE vaccination history. Follow-up investigations after discharge indicated that seven laboratory-confirmed JE patients without JE vaccinations had relatively poor prognoses, with an average Modified Rankin Scale (MRS) score of 2.6 when compared with the other five laboratory-confirmed, JE-vaccinated patients with an average MRS score of 0.5. The observation of pediatric JE cases among those with a history of JE vaccination warrants further attention.


Assuntos
Encefalite Japonesa/epidemiologia , Vacinas contra Encefalite Japonesa/administração & dosagem , Pequim/epidemiologia , Criança , Pré-Escolar , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Encefalite Japonesa/diagnóstico , Encefalite Japonesa/virologia , Feminino , Humanos , Masculino , Prognóstico
7.
Biomed Environ Sci ; 29(6): 443-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27470105

RESUMO

Ebola virus disease reemerged in Western Africa in 2014. Chinese Center for Disease Control and Prevention dispatched the first Ebola virus (EBOV) detection team to run newly established Sierra Leone-China Friendship Biological Safety Laboratory. The aims of study were to understand epidemiology, clinical manifestations and survival time of EBOV in patient's blood. A total of 913 specimens were tested between March 11 and April 20, 2015. EBOV positivity occurred in 7.37% of the blood and 0.53% in throat swabs. Most commonly reported symptoms of laboratory confirmed patients were intense fatigue, anorexia, and fever. EBOV RNAs persisted in blood for almost 4 weeks and the real-time RT-PCR Ct values showed close correlation with the sampling time after onset.


Assuntos
Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/sangue , Adolescente , Adulto , Idoso , Sangue/virologia , Criança , Pré-Escolar , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/virologia , Humanos , Lactente , Laboratórios , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Serra Leoa/epidemiologia , Adulto Jovem
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 550-4, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-27209767

RESUMO

Pyroelectric X-ray generator is implemented, and an X-ray fluorescence spectrometer is accomplished by combining the pyroelectric X-ray generator with a high energy resolution silicon drift detector. Firstly, the parameters of the X-ray generator are decided by analyzing and calculating the influence of the thickness of the pyroelectriccrystal and the thickness of the target on emitted X-ray. Secondly, the emitted X-ray is measured. The energy of emitted X-ray is from 1 to 27 keV, containing the characteristic X-ray of Cu and Ta, and the max counting rate is more than 3 000 per second. The measurement also proves that the detector of the spectrometer has a high energy resolution which the FWMH is 210 eV at 8. 05 keV. Lastly, samples of Fe, Ti, Cr and high-Ti basalt are analyzed using the spectrometer, and the results are agreed with the elements of the samples. It shows that the spectrometer consisting of a pyroelectric X-ray generator and a silicon drift detector is effective for element analysis. Additionally, because each part of the spectrometer has a small volume, it can be easily modified to a portable one which is suitable for non-destructive, on-site and quick element analysis.

9.
Neurochem Res ; 40(8): 1655-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26134310

RESUMO

Protocatechuic acid (PA), a major metabolite of anthocyanins, has been reported to possess antioxidant and anti-inflammatory activities. However, the effects of PA on LPS-induced inflammatory responses in microglia have not been reported. The aim of this study was to investigate the anti-inflammatory effects and molecular mechanisms of PA on LPS-stimulated BV2 microglia. The production of inflammatory mediators TNF-α, IL-6, IL-1ß, and PGE2 were detected by ELISA. TLR4, NF-κB and MAPKs activation were detected by western blotting. Our results demonstrated that PA dose-dependently inhibited LPS-induced TNF-α, IL-6, IL-1ß, and PGE2 production. In addition, PA suppressed LPS-induced TLR4 expression, NF-κB and MAPKs activation, which resulted in the inhibition of inflammatory mediators. In conclusion, these results suggested that PA exhibited anti-inflammatory effects on LPS-stimulated BV2 microglia and the mechanisms were involved in the inhibition of TLR4-mediated NF-κB and MAPKs signaling pathways.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hidroxibenzoatos/farmacologia , Lipopolissacarídeos/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Microglia/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Microglia/metabolismo , NF-kappa B/metabolismo
10.
Biomed Environ Sci ; 28(5): 374-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26055565

RESUMO

A real-time RT-PCR (RT-qPCR) assay for the detection of Tahyna virus was developed to monitor Tahyna virus infection in field-collected vector mosquito samples. The targets selected for the assay were S segment sequences encoding the nucleocapsid protein from the Tahyna virus. Primers and probes were selected in conserved regions by aligning genetic sequences from various Tahyna virus strains available from GenBank. The sensitivity of the RT-qPCR approach was compared to that of a standard plaque assay in BHK cells. RT-qPCR assay can detect 4.8 PFU of titrated Tahyna virus. Assay specificities were determined by testing a battery of arboviruses, including representative strains of Tahyna virus and other arthropod-borne viruses from China. Seven strains of Tahyna virus were confirmed as positive; the other seven species of arboviruses could not be detected by RT-qPCR. Additionally, the assay was used to detect Tahyna viral RNA in pooled mosquito samples. The RT-qPCR assay detected Tahyna virus in a sensitive, specific, and rapid manner; these findings support the use of the assay in viral surveillance.


Assuntos
Culicidae/virologia , Vírus da Encefalite da Califórnia/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Sensibilidade e Especificidade
11.
Biomed Environ Sci ; 27(4): 231-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24758751

RESUMO

OBJECTIVE: To determine the molecular characterization of full-length genome of Japanese encephalitis virus (JEV) genotype V. METHODS: The full-length nucleotide sequences of JEV strains isolated from different locations and sources were used in sequence and phylogenetic analysis. RESULTS: The full-length genome of genotypes V JEV, XZ0934, and Muar strain were composed of 10 983 and 10 988 nucleotides respectively and shared a lower level of identity with JEV genotypes I-IV, ranging from 78.4% (G I, KV1899) to 79.7% (G III, JaGAr01), for the nucleotide sequences, and from 90.0% (G I, KV1899) to 91.8% (G III, JaGAr01) for the amino acid sequences. The open reading frame (ORF) of JEV genotype V spanned nucleotides 96 to 10 397 and encoded 3 433 amino acids. Interestingly, a comparison with JEV genotype I-IV revealed that 3 nucleotides (encoded with a serine residue) were inserted in the NS4A gene of JEV genotype V, and the insertion of nucleotides was also found in downstream of the ORF stop codon in 3'-untranslated region. Moreover, numerous amino acid mutations were observed in 3 functional domains of the E gene of JEV genotype V. CONCLUSION: The molecular characterization of JEV genotype V is significantly different from that of the known genotypes I-IV. The mutations located in the coding region and the non-coding region may be molecular markers of JEV genotype V and warrant further studies to determine their effects on biology and immunogenicity of genotype V strains.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/genética , Genoma Viral , Sequência de Aminoácidos , Animais , Sequência de Bases , Culex/virologia , Genótipo , Humanos , Masculino , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Tibet , Adulto Jovem
12.
J Hazard Mater ; 464: 133015, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-37988942

RESUMO

In the face of diversified analytes, it is a great challenge and infeasible task to design and synthesize corresponding macrocyclic hosts to realize the ideal supramolecular sensing. Herein, we proposed a novel supramolecular sensing strategy, guest adaptative assay (GAA), in which analyte was quantitatively transformed under mild conditions to perfectly adapt to macrocyclic host. As a health-threatening "landmine" in cereals, aflatoxins were converted by the aid of alkali hydrolysis to satisfactorily obtain aflatoxins transformants in ionic state, resulting in sensitive response by the guanidinocalix[5]arene•fluorescein reporter pair. Surprisingly, the established strategy not only exhibited effective practicality in screening out high-risk cereals contaminated with aflatoxins, but also relieved the laborious task of macrocycle design and screening in supramolecular sensing.


Assuntos
Aflatoxinas , Aflatoxinas/análise , Grão Comestível/química
13.
Biomed Environ Sci ; 37(3): 294-302, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38582993

RESUMO

Objective: Viral encephalitis is an infectious disease severely affecting human health. It is caused by a wide variety of viral pathogens, including herpes viruses, flaviviruses, enteroviruses, and other viruses. The laboratory diagnosis of viral encephalitis is a worldwide challenge. Recently, high-throughput sequencing technology has provided new tools for diagnosing central nervous system infections. Thus, In this study, we established a multipathogen detection platform for viral encephalitis based on amplicon sequencing. Methods: We designed nine pairs of specific polymerase chain reaction (PCR) primers for the 12 viruses by reviewing the relevant literature. The detection ability of the primers was verified by software simulation and the detection of known positive samples. Amplicon sequencing was used to validate the samples, and consistency was compared with Sanger sequencing. Results: The results showed that the target sequences of various pathogens were obtained at a coverage depth level greater than 20×, and the sequence lengths were consistent with the sizes of the predicted amplicons. The sequences were verified using the National Center for Biotechnology Information BLAST, and all results were consistent with the results of Sanger sequencing. Conclusion: Amplicon-based high-throughput sequencing technology is feasible as a supplementary method for the pathogenic detection of viral encephalitis. It is also a useful tool for the high-volume screening of clinical samples.


Assuntos
Encefalite Viral , Vírus , Humanos , Encefalite Viral/diagnóstico , Vírus/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Reação em Cadeia da Polimerase , DNA Viral
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(5): 1360-3, 2013 May.
Artigo em Zh | MEDLINE | ID: mdl-23905352

RESUMO

Alpha particle X-ray spectrometer (APXS) is one of the payloads of Chang'E-3 lunar rover, the scientific objective of which is in-situ observation and off-line analysis of lunar regolith and rock. Distance measurement is one of the important functions for APXS to perform effective detection on the moon. The present paper will first give a brief introduction to APXS, and then analyze the specific requirements and constraints to realize distance measurement, at last present a new near infrared distance sensing algorithm by using the inflection point of response curve. The theoretical analysis and the experiment results verify the feasibility of this algorithm. Although the theoretical analysis shows that this method is not sensitive to the operating temperature and reflectance of the lunar surface, the solar infrared radiant intensity may make photosensor saturation. The solutions are reducing the gain of device and avoiding direct exposure to sun light.

15.
J Virol ; 85(19): 9847-53, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21697481

RESUMO

Japanese encephalitis virus (JEV), a mosquito-borne zoonotic pathogen, is one of the major causes of viral encephalitis worldwide. Previous phylogenetic studies based on the envelope protein indicated that there are four genotypes, and surveillance data suggest that genotype I is gradually replacing genotype III as the dominant strain. Here we report an evolutionary analysis based on 98 full-length genome sequences of JEV, including 67 new samples isolated from humans, pigs, mosquitoes, midges. and bats in affected areas. To investigate the relationships between the genotypes and the significance of genotype I in recent epidemics, we estimated evolutionary rates, ages of common ancestors, and population demographics. Our results indicate that the genotypes diverged in the order IV, III, II, and I and that the genetic diversity of genotype III has decreased rapidly while that of genotype I has increased gradually, consistent with its emergence as the dominant genotype.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/classificação , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/virologia , Genoma Viral , Animais , Ásia/epidemiologia , Análise por Conglomerados , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(7): 1965-8, 2012 Jul.
Artigo em Zh | MEDLINE | ID: mdl-23016364

RESUMO

Alpha particle X-ray spectrometer (APXS) is one of the payloads of Chang'E-3 lunar rover of China's Lunar Exploration Project. The present paper introduces briefly the components of APXS, how it works and its working environment on the lunar surface. The environmental temperature effect has been studied with simulations and experiments, and the results show that the temperature of the APXS sensor will be varying during the measuring on the lunar surface. And another experiment reveals that the energy resolution becomes worse if the sensor's temperature is varying. In this paper, a correction method based on Pearson's chi-squared test is presented. The method can improve the energy resolution when the sensor's temperature is varying. We have tested the method with the spectra acquired by APXS in the temperature varying period of Temperature Cycling Test, and the results show that the method is efficient and reliable.

17.
J Phys Condens Matter ; 34(19)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35158344

RESUMO

We study a non-Hermitian chiral topological superconductor system on two dimensional square lattice, from which we obtained a rich topological phase diagram and established an exact relationship between topological charge flow of exceptional points in generalized Brillouin zone and change of topological properties. Its rich topological phase diagram is the result of competition between anisotropy and non-Hermitian effect. This system belongs to class D according to AZ classification of non-Hermitian systems. Each topological phase can be characterized by a 2DZnumber, which indicates the number of chiral edge modes, and two 1DZ2numbers, which indicate the existence of zero modes at edge dislocations.

18.
J Phys Condens Matter ; 34(36)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35760065

RESUMO

Floquet engineering plays a key role in realizing novel dynamical topological states. The conventional Floquet engineering, however, only applies to time-periodic non-dissipative Hermitian systems, and for the open quantum systems, non-Hermitian processes usually occur. So far, it remains unclear how to characterize the topological phases of time-periodic open quantum systems via the frequency space Floquet Hamiltonian. Here, we propose the non-Floquet theory to solve the problem and illustrate it by a continuously time-periodic non-Hermitian bipartite chain. In non-Floquet theory, a temporal non-unitary transformation is exercised on the Floquet states, and the transformed Floquet spectrum restores the form of the Wannier-Stark ladder. Besides, we also show that different choices of the starting points of the driving period can result in different localization behavior, effects of which can reversely be utilized to design quantum detectors of phases in dissipative oscillating fields. Our methods are capable of describing topological features in dynamical open quantum systems with various driving types and can find its applications to construct new types of dynamical topological materials.

19.
Chem Commun (Camb) ; 57(94): 12627-12630, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34761762

RESUMO

Calixarenes are reportedly excellent activators that can remarkably improve the transport efficiencies of cell penetrating peptides. We employed eight calixarenes to systematically study the influence of structure on activation efficiency, which revealed that the scaffold, head group, and alkyl chain are all significant factors for activation efficiency by affecting affinities with the peptide and membrane.


Assuntos
Calixarenos/farmacologia , Peptídeos/metabolismo , Transporte Biológico/efeitos dos fármacos , Calixarenos/química , Avaliação Pré-Clínica de Medicamentos , Humanos , Estrutura Molecular
20.
Emerg Infect Dis ; 16(3): 514-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20202434

RESUMO

Banna viruses (BAVs) have been isolated from pigs, cattle, ticks, mosquitoes, and human encephalitis patients. We isolated and analyzed 20 BAVs newly isolated in China; this finding extends the distribution of BAVs from tropical zone to north temperate climates and demonstrate regional variations in BAV phylogeny and mosquito species possibly involved in BAV transmission.


Assuntos
Coltivirus/isolamento & purificação , Culicidae/virologia , Insetos Vetores/virologia , Aedes/virologia , Animais , Anopheles/virologia , China , Coltivirus/classificação , Coltivirus/genética , Culex/virologia , Culicidae/classificação , Humanos , Insetos Vetores/classificação , Filogenia , Infecções por Reoviridae/transmissão , Infecções por Reoviridae/virologia , Análise de Sequência de DNA
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