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1.
Acta Biochim Biophys Sin (Shanghai) ; 56(6): 844-856, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38606478

RESUMO

Lipid droplets (LDs) are dynamic organelles that store neutral lipids and are closely linked to obesity. Previous studies have suggested that Lycium barbarum polysaccharide (LBP) supplements can ameliorate obesity, but the underlying mechanisms remain unclear. In this study, we hypothesize that LBP alleviates LD accumulation in adipose tissue (AT) by inhibiting fat-specific protein 27 (Fsp27) through an activating transcription factor-6 (ATF6)/small-molecule sirtuin 1 (SIRT1)-dependent mechanism. LD accumulation in AT is induced in high-fat diet (HFD)-fed mice, and differentiation of 3T3-L1 preadipocytes (PAs) is induced. The ability of LBP to alleviate LD accumulation and the possible underlying mechanism are then investigated both in vivo and in vitro. The influences of LBP on the expressions of LD-associated genes ( ATF6 and Fsp27) are also detected. The results show that HFD and PA differentiation markedly increase LD accumulation in ATs and adipocytes, respectively, and these effects are markedly suppressed by LBP supplementation. Furthermore, LBP significantly activates SIRT1 and decreases ATF6 and Fsp27 expressions. Interestingly, the inhibitory effects of LBP are either abolished or exacerbated when ATF6 is overexpressed or silenced, respectively. Furthermore, SIRT1 level is transcriptionally regulated by LBP through opposite actions mediated by ATF6. Collectively, our findings suggest that LBP supplementation alleviates obesity by ameliorating LD accumulation, which might be partially mediated by an ATF6/SIRT1-dependent mechanism.


Assuntos
Células 3T3-L1 , Fator 6 Ativador da Transcrição , Tecido Adiposo , Medicamentos de Ervas Chinesas , Gotículas Lipídicas , Camundongos Endogâmicos C57BL , Sirtuína 1 , Animais , Sirtuína 1/metabolismo , Sirtuína 1/genética , Camundongos , Fator 6 Ativador da Transcrição/metabolismo , Fator 6 Ativador da Transcrição/genética , Tecido Adiposo/metabolismo , Tecido Adiposo/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/efeitos dos fármacos , Masculino , Medicamentos de Ervas Chinesas/farmacologia , Dieta Hiperlipídica/efeitos adversos , Adipócitos/metabolismo , Adipócitos/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/tratamento farmacológico , Lycium/química , Diferenciação Celular/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos
2.
Phys Chem Chem Phys ; 25(24): 16578-16586, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37309551

RESUMO

Achieving high spin polarization transport and a pure spin current is particularly desired in spintronics. We use a sawtooth graphene nanoribbon (STGNR) and its derived five-member ring structure (5-STGNR) to design new spin caloritronic devices, since they have been successfully prepared experimentally and have an interface with no lattice distortion. By using first-principle calculations combined with the non-equilibrium Green's function approach, we have studied the spin caloritronic transport properties of several STGNR-based devices, including the structures with symmetrical and asymmetrical edges, and found some excellent spin caloritronic properties, such as spin polarization, magnetoresistance and the spin Seebeck effect. By introducing a temperature difference, giant magnetoresistance and spin Seebeck effects are achieved in a heterojunction with a symmetrical edge, whereas spin polarization is more effective in a heterojunction with an asymmetrical edge. Meanwhile, the metal-semiconductor-metal junction, which is composed of STGNRs with a symmetrical edge, exhibits approximately 100% spin polarization and produces a perfect thermally induced pure spin current at room temperature. Our results indicate that the devices consisting of a sawtooth graphene nanoribbon and its derived five-member ring structure are promising novel spin caloritronic devices.

3.
Phys Chem Chem Phys ; 25(15): 10991-10997, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37016939

RESUMO

The discovery of two-dimensional (2D) magnetic materials makes it possible to realize in-plane magnetic tunnel junctions. In this study, the transport characteristics of an in-plane double barrier magnetic tunnel junction (IDB-MTJ) based on Cr2C have been studied by density functional theory combined with the nonequilibrium Green's function method. The results showed its maximum tunneling magnetoresistance ratio (TMR) value reached 6.58 × 1010. Its minimum TMR value (3.86 × 106) was also comparable to those of conventional field effect transistors (FETs). Due to its giant TMR and unique structural characteristics, the IDB-MTJ based on Cr2C has great potential applications in magnetic random access memory (MRAM) and logic computing.

4.
Phys Chem Chem Phys ; 25(13): 9548-9558, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36939192

RESUMO

The rapid rise of two-dimensional (2D) materials has aroused increasing interest in the fields of microelectronics and optoelectronics; various types of 2D van der Waals heterostructures (vdWHs), especially those based on MoS2, have been widely investigated in theory and experiment. However, the interfacial properties of MoS2 and the uncommon crystal surface of traditional three-dimensional (3D) metals are yet to be explored. In this paper, we studied heterostructures composed of MoS2 and metal(001) slabs, based on the first-principles calculations, and we uncovered that MoS2/Au(001) and MoS2/Ag(001) vdWHs reveal Schottky contacts, and MoS2/Cu(001) belongs to Ohmic contact and possesses ultrahigh electron tunneling probability at the equilibrium distance. Thus, the MoS2/Cu(001) heterostructure exhibits the best contact performance. Further investigations demonstrate that external longitudinal strain can modulate interfacial contact to engineer the Schottky-Ohmic contact transition and regulate interfacial charge transport. We believe that it is a general strategy to exploit longitudinal strain to improve interfacial contact performance to design and fabricate a multifunctional MoS2-based electronic device.

5.
Inorg Chem ; 61(43): 17353-17361, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36257300

RESUMO

The photocatalytic properties of Janus transition metal dichalcogenide (TMD) nanotubes are closely correlated with the electrostatic potential difference between their inner and outer surfaces (ΔΦ). However, due to some distraction from the tubular structures, it remains a great challenge to calculate their ΔΦ directly. Here, we creatively work out the ΔΦ of Janus MoSSe armchair single-walled nanotubes (A-SWNTs) with their corresponding building block models by first-principles calculations. The ΔΦ increases as the diameter reduces. After considering ΔΦ, we find that all of these MoSSe A-SWNTs possess suitable band-edge positions required for water redox reactions and high solar-to-hydrogen (STH) conversion efficiencies. The built-in field induced by the ΔΦ promotes the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) to proceed separately on the inner and outer surfaces. Especially, the photoexcited carriers exhibit adequate driving forces for OER and HER. Besides, constructing a double-walled nanotube can dramatically increase ΔΦ, which also further improves the separation and redox capacity of photoexcited carriers as well as the STH conversion efficiency. Moreover, all of these MoSSe armchair nanotubes have outstanding optical absorption in the visible light range. Our studies provide an effective strategy to improve the photocatalytic water-splitting performance of Janus TMD nanotubes.

6.
Phys Chem Chem Phys ; 24(39): 24328-24334, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36177914

RESUMO

Monolayer phosphorene has outstanding mechanical flexibility, making it rather attractive in flexible spintronics that are based on 2D materials. Here, we report a first-principles study on non-equilibrium electronic-transport properties of the Co/phosphorene/Co magnetic tunnel junction (MTJ) with two α-Co electrodes. The magnetic moments of the two electrodes are considered in the parallel configuration (PC) and the anti-parallel configuration (APC). The tunneling current through the MTJ is investigated at a small bias from 0 to 40 mV when mechanical bending is applied on the MTJ with different central angle (θ) values. For both the PC and APC, the tunneling current increases evidently and monotonously with increasing mechanical bending for 25° < θ < 40°, as compared to that without bending, which is mainly due to the reduced tunnel barrier. In the PC, the spin-injection efficiency (SIE) of the current is largely increased at a small bias from 0 to 40 mV for 25° ≤ θ ≤ 30° with a maximum of 90%, while the SIE is overall increased under all mechanical bending angles for the APC. The tunnel magnetoresistance is decreased with an increasing bias voltage, which can be largely enhanced for θ ≥ 25°, especially at small bias. Our results indicate that the Co/phosphorene/Co MTJ has promising applications in flexible low-power spintronic devices.

7.
Psychogeriatrics ; 22(2): 243-251, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35048467

RESUMO

BACKGROUND: Numerous studies have confirmed that the apolipoprotein E4 allele (APOE4) gene and arteriosclerosis (AS) have a combined effect on the occurrence of cognitive function impairment, and dyslipidaemia levels are significantly correlated with APOE4 levels and AS. Few studies have focused on the combined effect of the APOE4 gene and AS on cognitive function. Therefore, this study aimed to investigate the effect of APOE4 gene and AS acting together on cognitive function through dyslipidaemia levels, which could provide certain scientific research value for future studies. METHODS: A multi-stage cluster sampling method was used to investigate older adults aged 60 years and above in rural areas of Guizhou, China. The demographic sociological characteristics were collected, and laboratory tests, blood lipid measurements, and physical examinations were performed. Mini-Mental State Examination (MMSE) was used to determine cognitive function. Analysis of variance with two-factor factorial design was used to analyse the interaction between the APOE4 gene and AS on cognitive function and its domains. RESULTS: A total of 549 elderly subjects were eligible for this study. The result of the factorial design analysis revealed there was a significant interaction between the APOE4 gene and AS in terms of attention and numeracy (F = 6.878, P = 0.009). CONCLUSIONS: The combination of the APOE4 gene and AS leads to a decrease in the level of attention and numeracy domains, and certain attention should be focused on such populations in the future.


Assuntos
Arteriosclerose , Disfunção Cognitiva , Idoso , Apolipoproteína E4/genética , China , Disfunção Cognitiva/genética , Estudos Transversais , Humanos
8.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(1): 26-32, 2022 Jan 15.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-35177172

RESUMO

OBJECTIVES: To study the value of bedside echocardiography in predicting persistent patency of the ductus arteriosus during the early postnatal period in very low birth weight (VLBW) infants. METHODS: A retrospective analysis was performed for 51 VLBW infants who were admitted from March 2020 to June 2021, with an age of ≤3 days and a length of hospital stay of ≥14 days. According to the diameter of patent ductus arteriosus (PDA) on days 14 and 28 after birth, the infants were divided into three groups: large PDA group (PDA diameter ≥2 mm), small PDA group (PDA diameter <2 mm), and PDA closure group (PDA diameter =0 mm). The echocardiographic parameters measured at 72 hours after birth were compared among the three groups. The receiver operating characteristic (ROC) curve was used to evaluate the value of the echocardiographic parameters in predicting persistent patency of the ductus arteriosus (PDA≥2 mm) at the ages of 14 and 28 days. RESULTS: On day 14 after birth, there were 17 infants in the large PDA group, 11 in the small PDA group, and 23 in the PDA closure group. On day 28 after birth, there were 14 infants in the large PDA group, 9 in the small PDA group, and 26 in the PDA closure group. There were significant differences in gestational age, birth weight, rate of pulmonary surfactant use, and incidence rate of hypotension among the three groups (P<0.05). PDA diameter, end-diastolic velocity of the left pulmonary artery, left ventricular output, and left ventricular output/superior vena cava flow ratio measured at 72 hours after birth were associated with persistent patency of the ductus arteriosus at the ages of 14 and 28 days (P<0.05), and the ratio of the left atrium to aorta diameter was associated with persistent patency of the ductus arteriosus at the age of 28 days (P<0.05). The ROC curve analysis showed that the area under the curve that the PDA diameter measured at 72 hours after birth predicting the persistent patency of the ductus arteriosus at the ages of 14 and 28 days was the largest (0.841 and 0.927 respectively), followed by end-diastolic velocity of the left pulmonary artery, with the area under the curve of 0.793 and 0.833 respectively. CONCLUSIONS: The indicators obtained by beside echocardiography at 72 hours after birth, especially PDA diameter and end-diastolic velocity of the left pulmonary artery, can predict persistent patency of the ductus arteriosus at the ages of 14 and 28 days in VLBW infants, which provides a basis for the implementation of early targeted treatment strategy for PDA.


Assuntos
Permeabilidade do Canal Arterial , Permeabilidade do Canal Arterial/diagnóstico por imagem , Ecocardiografia , Humanos , Lactente , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Estudos Retrospectivos , Veia Cava Superior
9.
Langmuir ; 37(29): 8776-8788, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34266237

RESUMO

With the purpose of oil energy recovery as well as achieving efficiency of oil/water separation, hydrophobic mesh materials have attracted extensive attention. However, fabrication of the current methods is not environmentally friendly, has high energy consumption, and creates serious pollution. Inspired by lotus leaves and rose petals, a biomimetic superhydrophobic surface was fabricated prepared on a stainless steel mesh by an in situ chemical reduction method with simple operation and mild conditions. The results of SEM, XRD, and XPS demonstrated that the mesh shows a stable and uniform moss-like rough structured surface. The SSM/Ag/ODA mesh, which was modified by moss-like Ag nanoclusters and low surface energy agents, has excellent superhydrophobicity with an excellent oil/water separation efficiency that reached up to 99.8%. The silver mirror phenomenon formed by the Ag nanoclusters further confirmed that silver ions were reduced and attached to the surface of the mesh. Moreover, the mesh can maintain superhydrophobicity under harsh conditions, such as a high concentration of a salty solution, organic solvents, alkaline, acidic solution, and even long-time UV irradiation, etc. More importantly, the modified mesh has excellent physical stability, in which the water contact angle on the mesh can be maintained above 150° after harsh mechanical wear. The hydrophobic mesh showed great potential to be applied for highly efficient oil/water separation and oil energy recovery even under complex and harsh conditions.


Assuntos
Óleos , Prata , Biomimética , Interações Hidrofóbicas e Hidrofílicas , Telas Cirúrgicas
10.
Ann Clin Microbiol Antimicrob ; 19(1): 39, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32878629

RESUMO

Majocchi's granuloma is an uncommon fungal infection of the dermis and subcutaneous tissue. The most frequently identified cause of Majocchi's granuloma is anthropophilic Trichophyton rubrum, and it is most commonly located on the anterior aspect of the lower limbs in women. Here, we report a case of Majocchi's granuloma on the forearm, a site that is rarely involved, in a 62-year-old woman who had been bitten by a dog. Histological examination revealed a dense dermal infiltrate composed of lymphoplasmacytic cells and neutrophils, with hyphae in the dermis. The presence of the fungus, Trichophyton tonsurans, was confirmed by mycological examination and molecular methods. Therefore, histological and mycological examination confirmed the diagnosis of Majocchi's granuloma. The patient was treated with local moxibustion and itraconazole, 200 mg/day, for 60 days, which facilitated a complete resolution of the lesions.


Assuntos
Mordeduras e Picadas/complicações , Granuloma/diagnóstico , Granuloma/microbiologia , Tinha/diagnóstico , Tinha/microbiologia , Animais , Antifúngicos/uso terapêutico , Arthrodermataceae/isolamento & purificação , Cães , Feminino , Granuloma/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Tinha/tratamento farmacológico
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(6): 638-642, 2020 Jun.
Artigo em Zh | MEDLINE | ID: mdl-32571465

RESUMO

OBJECTIVE: To study the clinical features of neonatal enterovirus infection, especially severe enterovirus infection. METHODS: A retrospective analysis was performed for the clinical data of 244 neonates with enterovirus infection. According to the severity of infection, they were divided into a common infection group with 231 neonates and a severe infection group with 13 neonates. Clinical features were compared between the two groups. RESULTS: Of the 244 neonates, 207 (84.8%) developed the disease in May to October, with the highest number of patients in June to July. Compared with the common infection group, the severe infection group had a significantly lower gestational age at birth and a significantly higher proportion of preterm infants (P<0.05). Compared with the common infection group, the severe infection group had a significantly earlier onset time (P<0.05) and significantly higher incidence rates of skin petechiae and ecchymosis, respiratory symptoms, sepsis-like manifestations (poor appetite, crying less, and less movement), concomitant diseases (such as pneumonia, myocarditis, necrotic hepatitis, and coagulation disorder), thrombocytopenia, prolonged prothrombin time, elevated creatine kinase-MB, and elevated alanine aminotransferase (P<0.05). The severe infection group had a significantly higher mortality rate than the common infection group (P<0.05). CONCLUSIONS: There are significant differences in onset time, common clinical manifestations, and concomitant diseases between the neonates with common and severe enterovirus infection. In the enterovirus epidemic season, if the neonates have rashes and/or sepsis-like manifestations such as poor appetite and less movement, especially if the laboratory tests suggest liver damage and coagulation dysfunction, it is necessary to pay particular attention to the possibility of severe enterovirus infection.


Assuntos
Infecções por Enterovirus , Enterovirus , Sepse , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Estudos Retrospectivos
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(3): 226-230, 2020 Mar.
Artigo em Zh | MEDLINE | ID: mdl-32204758

RESUMO

Since December 2019, the outbreak of coronavirus disease (COVID-19) has become the most serious public health issue. As the special population with immature immune function, newborns with COVID-19 have been reported. Newborns with suspected or confirmed COVID-19 should be transferred to designated hospitals for isolation treatment. An emergency transfer response plan for newborns with COVID-19 has been worked out. This plan puts forward the indications for neonatal COVID-19 transfer, organization management, protection strategies for medical staff, work procedures, and disinfection methods for transfer equipment, in order to provide guidance and suggestions for the inter-hospital transfer of suspected or confirmed neonatal COVID-19.


Assuntos
Infecções por Coronavirus , Pneumonia Viral , Betacoronavirus , COVID-19 , Hospitais , Humanos , Recém-Nascido , SARS-CoV-2
13.
J Cell Biochem ; 120(5): 6926-6936, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30652355

RESUMO

Emerging evidence has shown that the long noncoding RNA urothelial carcinoma-associated 1 (UCA1) plays a tumor-promoting role in colorectal cancer, while miR-28-5p shows tumor-inhibitory activity in several tumor types. However, the mechanisms both of these in colon cancer progression are still unknown. In this work, the detailed roles and mechanisms of UCA1 and its target genes in colon cancer were studied. The results showed that UCA1 was upregulated in colon cancer tissues when compared with the adjacent nonhumorous tissues, as well as in the various colon cancer cell lines, but the expression of miR-28-5p showed an opposite trend. Furthermore, a high UCA1 level in colon cancer tissues is positively associated with the tumor size and advanced tumor stages. Functional assays revealed that both UCA1 knockdown and miR-28-5p overexpression could inhibit colon cancer cell growth and migration. Further mechanistic studies indicated that UCA1 knockdown played tumor suppressive roles in SW480 and HT116 cells through binding with miR-28-5p. We also, for the first time, identified HOXB3 as the target gene of miR-28-5p and that HOXB3 overexpression could mediate the functions of UCA1 in cell proliferation and migration of colon cancer cells. In conclusion, our data provided evidence for the regulatory network of UCA1/miR-28-5p/HOXB3 in colon cancer, suggesting that UCA1, miR-28-5p, and HOXB3 are the potential targets for colon cancer therapy.

14.
Ecotoxicol Environ Saf ; 170: 722-731, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30580167

RESUMO

Waste biomass and sewage sludge were used to obtain an adsorbent material with excellent performance qualities by adopting a KOH activation process via one-stage (ACone) or two-stage (ACtwo) co-pyrolysis. The main purpose of this work was to investigate the effects of both methods in terms of the physicochemical properties and adsorption capacities for methylene blue (MB). Textural analyses revealed that the surface area (Stot= 683.82 m2/g) and total pore volume (Vtot= 0.72 cm3/g) of ACtwo were more than two-fold compared with ACone (Stot= 285.33 m2/g; Vtot= 0.35 cm3/g). Thus, two-stage co-pyrolysis produced activated carbon with increased porosity, which was favorable for MB adsorption. Nevertheless, the intensity of the surface functional groups of ACtwo was weaker than for ACone, which could be due to the pore-forming mechanism. Two-stage co-pyrolysis increased the yield and aromaticity of activated carbon, but sufficient activation caused more functional groups to decompose. For the adsorbate MB, the maximum adsorption capacity of ACtwo (602.80 mg/g) was more than five-fold greater than that of ACone (101.88 mg/g), due to its excellent porosity properties. Furthermore, the interactions of MB molecules with activated carbon were via hydrogen bonds and electrostatic attraction. The adsorption process of MB onto activated carbon was accurately described by the pseudo-second-order kinetic model. Adsorption equilibrium evaluated Langmuir isotherms demonstrated that MB formed a monolayer by adsorption onto the activated carbon. Adsorption thermodynamics was used to investigate the influence of temperature on the adsorption process. Thermodynamic parameters indicated that MB adsorption onto activated carbon was spontaneous and endothermic. In conclusion, our results showed that two-stage co-pyrolysis improves the adsorption capabilities of activated carbon, so achieving better economic value from waste materials.


Assuntos
Carvão Vegetal/química , Cocos/química , Pirólise , Esgotos/química , Adsorção , Carbono/química , Carvão Vegetal/síntese química , Frutas , Ligação de Hidrogênio , Cinética , Azul de Metileno/química , Porosidade , Termodinâmica
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(12): 1218-1222, 2019 Dec.
Artigo em Zh | MEDLINE | ID: mdl-31874663

RESUMO

A girl was admitted to the hospital on day 2 after birth due to jaundice of the skin and sclera for half a day. The main clinical manifestations were persistent severe jaundice and thrombocytopenia, and she was finally diagnosed with congenital thrombotic thrombocytopenic purpura (TTP). Her conditions were improved after phototherapy, exchange transfusion, and infusion of fresh frozen plasma, red blood cells, and platelets. Gene detection showed a homozygous mutation of c.3650T>C(p.I1217T) in the ADAMTS13 gene, while her parents had a heterozygous mutation at this locus. Congenital TTP is a rare autosomal recessive disease, and timely infusion of fresh frozen plasma can achieve a good clinical outcome. This is the first case of congenital TTP caused by homozygous mutation at this locus reported in China and overseas.


Assuntos
Púrpura Trombocitopênica Trombótica , Proteína ADAMTS13 , Anemia , China , Feminino , Humanos , Hiperbilirrubinemia , Recém-Nascido
16.
Pak J Med Sci ; 34(2): 385-389, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29805413

RESUMO

OBJECTIVE: To detect the serum IgE and allergen-specific IgE levels of pediatric patients with chronic urticaria, and to analyze the distribution characteristics of allergens. METHODS: Ninety-six patients with chronic urticaria admitted in our hospital, which were not administered antihistamine 10 days before detection or glucocorticoid 20 days before detection, were selected. Their serum IgE levels were measured and 34 antigens were analyzed. RESULTS: Ninety-two of the ninety-six patients were detected as serum IgE positive (positive rate: 95.83%). The positive serum IgE levels did not significantly change along with season (P>0.05). The positive detection rate of antigens was 95.83% (92/96), and the top five potent antigens included house dust mite, flour mite, histamine, egg yolk and egg white. CONCLUSION: Dust mite, as the most common antigen for pediatric patients with chronic urticaria, is prone to variations of specific IgE positive rate along with season. The results may be associated with the persistent warm and humid climate in this region.

17.
Phys Chem Chem Phys ; 18(3): 1601-6, 2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26675820

RESUMO

Monolayer black phosphorus (MBP) is an interesting emerging electronic material with a direct band gap and relatively high carrier mobility. In this work we report a theoretical investigation of nonequilibrium spin injection and spin-polarized quantum transport in MBP from ferromagnetic Ni contacts, in two-dimensional magnetic tunneling structures. We investigate physical properties such as the spin injection efficiency, the tunnel magnetoresistance ratio, spin-polarized currents, charge currents and transmission coefficients as a function of external bias voltage, for two different device contact structures where MBP is contacted by Ni(111) and by Ni(100). While both structures are predicted to give respectable spin-polarized quantum transport, the Ni(100)/MBP/Ni(100) trilayer has the superior properties where the spin injection and magnetoresistance ratio maintains almost a constant value against the bias voltage. The nonequilibrium quantum transport phenomenon is understood by analyzing the transmission spectrum at nonequilibrium.

18.
Zoolog Sci ; 31(12): 781-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25483789

RESUMO

Many migratory bird species fly during the night (nocturnal migrants) and have been shown to display some phototaxis to artificial light. During 2006 to 2009, we investigated phototaxis in nocturnal migrants at Jinshan Yakou in Xinping County (N23°56', E101°30'; 2400 m above sea-level), and at the Niaowang Mountain in Funing County (N23°30', E105°35'; 1400 m above sea-level), both in the Yunnan Province of Southwest China. A total of 5069 birds, representing 129 species, were captured by mist-netting and artificial light. The extent of phototaxis effect on bird migration was examined during all four seasons, three phases of the moon, and under two weather conditions (mist and wind). Data were statistically analyzed to determine the extent to which these factors may impact phototaxis of nocturnal migrants. The results point to phototaxis in birds migrating in the spring and autumn, especially in the autumn. Furthermore, migrating birds were more readily attracted to artificial lights during nights with little moonlight, mist, and a headwind. Regardless of the initial orientation in which birds flew, either following the wind or against the wind, birds would always fly against the wind when flying towards the light. This study broadens our understanding of the nocturnal bird migration, potentially resulting in improved bird ringing practices, increased awareness, and better policies regarding bird protection.


Assuntos
Migração Animal/fisiologia , Aves/fisiologia , Ritmo Circadiano , Estações do Ano , Animais , Aves/classificação , China , Voo Animal/fisiologia , Luz , Especificidade da Espécie
19.
Infect Drug Resist ; 17: 727-732, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38433782

RESUMO

Tinea capitis, a common cutaneous fungal infection, shows an increasing prevalence with the increasing number of pets. We present tinea capitis in a 4-year-old girl presenting without typical symptoms such as alopecia or hair breakage. After a comprehensive evaluation including dermoscopy, Wood's light, direct KOH fluorescent staining, scanning electron microscopy, fungal culture and mass spectrometry analysis, a diagnosis of tinea capitis infected Microsporum canis carried by domestic cats was made. We preliminarily explored the two modes of hair erosion by tinea capitis fungi and analyzed the possibility of the feature in this case. This case highlights the importance of accurate diagnosis and appropriate therapeutic intervention in cases of paediatric tinea capitis, particularly in households with resident pets.

20.
Sci Rep ; 14(1): 14149, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898041

RESUMO

Using the principles of density functional theory (DFT) and nonequilibrium Green's function (NEGF), We thoroughly researched carbon-doped zigzag boron nitride nanoribbons (ZBNNRs) to understand their electronic behavior and transport properties. Intriguingly, we discovered that careful doping can transform carbon-doped ZBNNRs into a spintronic nanodevice with distinct transport features. Our model showed a giant magnetoresistance (GMR) up to a whopping 10 5 under mild bias conditions. Plus, we spotted a spin rectifier having a significant rectification ratio (RR) of 10 4 . Our calculated transmission spectra have nicely explained why there's a GMR up to 10 5 for spin-up current at biases of - 1.2 V, - 1.1 V, and - 1.0 V, and also accounted for a GMR up to 10 3 -10 5 for spin-down current at biases of 1.0 V, 1.1 V, and 1.2 V. Similarly, the transmission spectra elucidate that at biases of 1.0 V, 1.1 V, and 1.2 V for spin-up, and at biases of 1.1 V and 1.2 V for spin-down in APMO, the RRs reach 10 4 . Our research shines a light on a promising route to push forward the high-performance spintronics technology of ZBNNRs using carbon atom doping. These insights hint that our models could be game-changers in the sphere of nanoscale spintronic devices.

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