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1.
Clin Infect Dis ; 76(3): e148-e154, 2023 02 08.
Article in English | MEDLINE | ID: mdl-35870128

ABSTRACT

BACKGROUND: Acceleration of negative respiratory conversion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in patients with coronavirus disease 2019 (COVID-19) might reduce viral transmission. Nirmatrelvir/ritonavir is a new antiviral agent recently approved for treatment of COVID-19 that has the potential to facilitate negative conversion. METHODS: A cohort of hospitalized adult patients with mild-to-moderate COVID-19 who had a high risk for progression to severe disease were studied. These patients presented with COVID-19 symptoms between 5 March and 5 April 2022. The time from positive to negative upper respiratory reverse transcription-polymerase chain reaction (RT-PCR) conversion was assessed by Kaplan-Meier plots and Cox proportional hazards regression with the adjustment for patients' baseline demographic and clinical characteristics. RESULTS: There were 258 patients treated with nirmatrelvir/ritonavir and 224 nontreated patients who had mild-to-moderate COVID-19. The median (interquartile range) time for patients who converted from positive to negative RT-PCR was 10 days (7-12 days) in patients treated ≤5 days after symptom onset and 17 days (12-21 days) in nontreated patients. The proportions of patients with a negative conversion at day 15 were 89.7% and 42.0% in treated patients and nontreated patients, corresponding to a hazard ratio of 4.33 (95% confidence interval, 3.31-5.65). Adjustment for baseline differences between the groups had little effect on the association. Subgroup analysis on treated patients suggests that time to negative conversion did not vary with the patients' baseline characteristics. CONCLUSIONS: This cohort study of high-risk patients with mild-to-moderate COVID-19 found an association between nirmatrelvir/ritonavir treatment and accelerated negative RT-PCR respiratory SARS-CoV-2 conversion that might reduce the risk of viral shedding and disease transmission.


Subject(s)
COVID-19 , Adult , Humans , SARS-CoV-2 , Ritonavir/therapeutic use , Reverse Transcriptase Polymerase Chain Reaction , Cohort Studies , Reverse Transcription , COVID-19 Drug Treatment , COVID-19 Testing
2.
Int Microbiol ; 24(1): 25-35, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32691258

ABSTRACT

PURPOSE: Sporothrix schenckii is a thermally dimorphic fungus. In a saprotrophic environment or culturing at 25 °C, it grows as mycelia, whereas in host tissues or culturing at 37 °C, it undergoes dimorphic transition and division into pathogenic yeast cells. S. schenckii can cause serious disseminated sporotrichosis in immunocompromised hosts and presents an emerging global health problem. The mycelium-to-yeast transition was a consequence of the adaptive process to different environment. Some studies showed that the transition was significantly related to the virulence and pathogenesis of dimorphic fungi. However the genetic mechanisms of this complicated biological process are poorly understood. METHOD: Our study presented a comparative transcriptomic analysis perspective on temperature stress in a visceral isolates of S. schenckii, obtaining more genetic information related to dimorphic transition. RESULTS: The 9.38 Gbp dataset was generated and assembled into 14,423 unigenes. Compared with gene and protein databases, 9561 unigenes were annotated. Comparative analysis identified 1259 genes expressed differentially in mycelium and yeast phase, and were categorized into a number of important biological processes, such as synthesis and metabolism, transmembrane transport, biocatalysis, oxidation reduction, and cellular signal transduction. CONCLUSIONS: The findings suggested that temperature-dependent transition was tightly associated with stress adaptation, growth and development, signal regulation, adhesion, and colonization, which was predicted to be related with virulence and pathogenesis. Collection of these data should offer fine-scale insights into the mechanisms of dimorphism and pathogenesis of S. schenckii, and meanwhile facilitate the evolutionary and function studies of other dimorphic fungi.


Subject(s)
Fungal Proteins/genetics , Sporothrix/growth & development , Sporothrix/genetics , Sporotrichosis/microbiology , Animals , Fungal Proteins/metabolism , Gene Expression Profiling , Gene Expression Regulation, Developmental , Gene Expression Regulation, Fungal , Humans , Mycelium/genetics , Mycelium/growth & development , Mycelium/physiology , Sporothrix/physiology , Stress, Physiological , Temperature , Transcription, Genetic
3.
J Med Virol ; 87(9): 1573-7, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25940435

ABSTRACT

Hepatitis E virus (HEV) infection is an important public health concern worldwide, especially in developing countries, causing waterborne outbreaks as well as sporadic autochthonous hepatitis. China is usually considered to be a HEV-endemic area, but the prevalence of HEV infection in children in mainland China remains unclear. Between May 2013 and July 2014, a cross-sectional study was conducted to estimate the seroprevalence and potential risk factors associated with the acquisition of HEV infection by children in China. A total of 1,500 healthy children (range 1-18; 942 and 558 from urban and rural areas, respectively) were recruited to examine for the presence of anti-HEV IgG and IgM antibodies by enzyme-linked immunosorbent assay. Socio-demographic and behavioral characteristics from the examined children were obtained. The overall seroprevalence of HEV in the examined children was 14.93%. Of these, 174 (11.60%) were positive for only anti-HEV IgG antibodies, 50 (3.33%) were IgM positive and IgG negative, and 44 (2.93%) were positive for both anti-HEV IgG and IgM antibodies. Age, type of residence area, contact with pigs, and source of drinking water were found to be associated with HEV infection. These findings demonstrated the high prevalence of HEV and the considerable potential for the transmission of HEV infection in children in China.


Subject(s)
Hepatitis Antibodies/blood , Hepatitis E virus/immunology , Hepatitis E/epidemiology , Seroepidemiologic Studies , Adolescent , Animals , Child , Child, Preschool , China/epidemiology , Cross-Sectional Studies , Demography , Enzyme-Linked Immunosorbent Assay , Female , Hepatitis E/transmission , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Infant , Male , Risk Factors , Swine
4.
Zhonghua Yi Xue Za Zhi ; 94(28): 2212-5, 2014 Jul 22.
Article in Zh | MEDLINE | ID: mdl-25331475

ABSTRACT

OBJECTIVE: To explore the effects of early cigarette smoke exposure on the immune functions of T-lymphocyte subsets in asthmatic mice model. METHODS: Forty mice (20 days) were randomly allocated into four groups: air control group, cigarette smoke (CS) control group, air+ovalbumin (OVA) group, and CS+OVA group (n = 10 each). The CS control and CS+OVA groups were exposed to cigarette smoke for 3 weeks while the other two groups exposed to air. At an age of 8 weeks, air+OVA and CS+OVA groups had OVA sensitization for establishing an asthma model while the other two groups were selected as control. The percentage of regulatory T cells (Treg), effect of T cell (Te) subgroup including T helper type (Th)1, Th2 and Th17 in splenic mononuclear T cell were determined by flow cytometry. The levels of transforming growth factor-ß (TGF-ß), interleukin (IL)-4, IL-5, IL-10, IL-13, IL-17A and interferon-γ (IFN-γ) in bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay (ELISA). And the percentage ratios of Treg to Te were compared among four groups. RESULTS: The percentages of Th1, Th2, Th17 and Treg in splenic mononuclear of CS+OVA group ((21.47 ± 2.84)%, (16.33 ± 3.02)%, (1.89 ± 0.23)% and (2.92 ± 0.40)%, respectively) were all significantly higher than those in air+OVA group ((14.78 ± 2.21)%, (9.72 ± 1.46)%, (1.01 ± 0.12)% and (1.84 ± 0.22)% , respectively), the levels of IL-4, IL-5, IL-10, IL-13, IL-17A, IFN- γ and TGF-ß in BALF of CS+OVA group ((138.6 ± 18.9), (195.3 ± 32.6), (22.8 ± 3.9), (716.9 ± 123.6), (62.8 ± 7.9), (173.2 ± 25.5) and (66.5 ± 8.2) ng/L, respectively) were all significantly higher than those in air+OVA group ((90.1 ± 13.7), (128.5 ± 21.8), (14.4 ± 2.9), (421.4 ± 60.4), (40.4 ± 6.2), (113.8 ± 16.9) and (42.9 ± 3.8) ng/L, respectively) (all P < 0.05). No significant difference of Treg/Te percentage ratio existed in mice spleen mononuclear cells between air+OVA group and CS+OVA group (P > 0.05). CONCLUSION: Early cigarette smoke exposure could significantly exacerbate T cell immune dysfunction in asthmatic mice.


Subject(s)
Asthma/immunology , Smoking/adverse effects , T-Lymphocyte Subsets/immunology , Animals , Bronchoalveolar Lavage Fluid , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Interferon-gamma , Interleukins , Mice , Nicotiana
5.
Micromachines (Basel) ; 14(6)2023 May 29.
Article in English | MEDLINE | ID: mdl-37374735

ABSTRACT

With the rapid development of semiconductor technology, traditional equation-based modeling faces challenges in accuracy and development time. To overcome these limitations, neural network (NN)-based modeling methods have been proposed. However, the NN-based compact model encounters two major issues. Firstly, it exhibits unphysical behaviors such as un-smoothness and non-monotonicity, which hinder its practical use. Secondly, finding an appropriate NN structure with high accuracy requires expertise and is time-consuming. In this paper, we propose an Automatic Physical-Informed Neural Network (AutoPINN) generation framework to solve these challenges. The framework consists of two parts: the Physics-Informed Neural Network (PINN) and the two-step Automatic Neural Network (AutoNN). The PINN is introduced to resolve unphysical issues by incorporating physical information. The AutoNN assists the PINN in automatically determining an optimal structure without human involvement. We evaluate the proposed AutoPINN framework on the gate-all-around transistor device. The results demonstrate that AutoPINN achieves an error of less than 0.05%. The generalization of our NN is promising, as validated by the test error and the loss landscape. The results demonstrate smoothness in high-order derivatives, and the monotonicity can be well-preserved. We believe that this work has the potential to accelerate the development and simulation process of emerging devices.

6.
Micromachines (Basel) ; 15(1)2023 Dec 30.
Article in English | MEDLINE | ID: mdl-38258204

ABSTRACT

With the CMOS technology downscaling to the deep nanoscale, the aging effects of devices degrade circuit performance and even lead to functional failure. The stress analysis is critical to evaluate the influence of aging effects on digital circuits. Some related analytical work has recently focused on reliability-aware circuit analysis. Nevertheless, the aging dependence among different devices is not considered, which will induce errors of degradation evaluation in the digital circuit. In order to improve the accuracy of reliability-aware static timing analysis, an improved analytical method is proposed by employing logical resolving. Experimental results show that the proposed method has a better evaluation accuracy of aging path delay than traditional strategies. For aging timing evaluation on aging paths, excessive pessimism can be reduced by employing the proposed method. And, a 378× speedup is achieved while having a 0.56% relative error compared with precise SPICE simulation. Moreover, the circuit performance sacrifice of an aging-aware synthesis flow with the proposed method can be decreased. Due to the high efficiency and high accuracy, the proposed method can meet the speed demands of large-scale digital circuit reliability analysis while achieving transistor simulation accuracy.

7.
Emerg Microbes Infect ; 12(1): 2149935, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36398721

ABSTRACT

It is critical to determine the real-world performance of vaccines against coronavirus disease 2019 (COVID-19) so that appropriate treatments and policies can be implemented. There was a rapid wave of infections by the Omicron variant in Jilin Province (China) during spring 2022. We examined the effectiveness of inactivated vaccines against Omicron using real-world data from this epidemic. This retrospective case-case study of vaccine effectiveness (VE) examined infected patients who were quarantined and treated from April 16 to June 8, 2022 and responded to an electronic questionnaire. Data were analyzed by univariable and multivariable analyses. A total of 2968 cases with SARS-CoV-2 infections (asymptomatic: 1061, mild disease: 1763, pneumonia: 126, severe disease: 18) were enrolled in the study. Multivariable regression indicated that the risk for pneumonia or severe disease was greater in those who were older or had underlying diseases, but was less in those who received COVID-19 vaccines. Relative to no vaccination, VE against the composite of pneumonia and severe disease was significant for those who received 2 doses (60.1%, 95%CI: 40.0%, 73.5%) or 3 doses (68.1%, 95%CI: 44.6%, 81.7%), and VE was similar in the subgroups of males and females. However, VE against the composite of all three classes of symptomatic diseases was not significant overall, nor after stratification by sex. There was no statistical difference in the VE of vaccines from different manufacturers. The inactivated COVID-19 vaccines protected patients against pneumonia and severe disease from Omicron infection, and booster vaccination enhanced this effect.


Subject(s)
COVID-19 , Pneumonia , Female , Male , Humans , COVID-19 Vaccines , SARS-CoV-2 , COVID-19/prevention & control , Retrospective Studies , China/epidemiology
8.
Front Pediatr ; 10: 990944, 2022.
Article in English | MEDLINE | ID: mdl-36458144

ABSTRACT

Background: Recently, there was an outbreak in China of the Omicron (B.1.1.529) variant, the corresponding clinical characteristics of Chinese children with the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were then reviewed and summarized retrospectively. Methods: From March to April 2022, a total of 134 children infected with the Omicron variant were included in the study. Data such as sex, age, clinical symptoms, laboratory examinations, and imaging features were collected for further analyses. Results: Half of the children were male and the median age was 5.67 years. The most SARS-CoV-2 Omicron variant was identified in mild (122, 91%), and the most three frequent symptoms were as cough (108, 80.6%), fever (75, 56%), and sore throat (38, 28.4%). Among age groups, no significant difference was observed in the distribution of symptoms, and no statistical difference was found in different clinical types among sex or age groups. Laboratory examinations revealed that white blood cells, neutrophils, and hemoglobin decreased; and monocytes, C-reactive protein (CRP), and aspartate aminotransferase (AST) increased. Further analyses showed that neutrophils, hemoglobin, CRP, and AST exhibited significant differences among age groups. Radiological abnormalities were found in nine cases, with small patchy high-density shadows. Of the 76 cured cases discharged from the hospital, the median hospital stay was 13 days (mean, 12 days). Conclusions: In China, most children with Omicron SARS-CoV-2 infection have mild presentation. The findings of this study may help other districts improve the management of children with Omicron SARS-CoV-2 infection in China.

9.
Autoimmunity ; 55(6): 351-359, 2022 09.
Article in English | MEDLINE | ID: mdl-35766145

ABSTRACT

BACKGROUND: Regulatory B cells (Bregs) are a subset of B cells that secrete interleukin 10 (IL-10) and play a vital role in suppressing the immune response. The aim of this study was to evaluate the proportion of Bregs in patients with thymoma. METHODS: The proportions of subgroups of Bregs in 23 patients with thymoma and 15 healthy controls were detected by flow cytometry. The serum IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ, and TNF-α levels of the subjects were measured using a cytometric bead array (CBA). RESULTS: The proportions of circulating IL-10+ B cells, IL-10+CD24hiCD38hi Bregs, and IL-10+CD24hiCD27+ Bregs and the serum IL-10 level were significantly higher in patients with thymoma than in the control group and were negatively correlated with the Karnofsky Performance Scale (KPS) score. The serum levels of cytokines IL-2, IL-6, IFN-γ, and TNF-α were higher and serum IL-17A level was lower in patients with thymoma. Patients with advanced-stage thymoma exhibited significantly higher proportions of IL-10-producing Bregs and a higher serum IL-10 level. After tumour resection, the frequency of circulating IL-10+CD24hiCD38hi Bregs and the serum IL-10 level were significantly decreased in patients with thymoma. The serum IL-10 levels exhibited the best accuracy in assessing the risk of thymoma occurrence in this study. CONCLUSIONS: The expression of IL-10 produced by Bregs is increased in patients with thymoma, particularly those with advanced-stage disease, which may suggest that Bregs are involved in the pathogenesis and progression of thymoma.


Subject(s)
B-Lymphocytes, Regulatory , Thymoma , Thymus Neoplasms , B-Lymphocytes, Regulatory/metabolism , B-Lymphocytes, Regulatory/pathology , Humans , Interleukin-10/metabolism , Interleukin-17/metabolism , Interleukin-2/metabolism , Interleukin-6/metabolism , Thymoma/metabolism , Thymoma/pathology , Thymus Neoplasms/diagnosis , Thymus Neoplasms/metabolism , Thymus Neoplasms/pathology , Tumor Necrosis Factor-alpha/metabolism
10.
Animals (Basel) ; 12(19)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36230279

ABSTRACT

Specific pathogen-free (SPF) grade laboratory animals are kept in specific cages for life. The limited space could affect the characterization of colonization and dynamic changes related to gut microorganisms, and affect adipokines, even further affecting the fat synthesis and muscle quality of animals. The objective of this study was to analyze the stocking density on the dynamic distribution of gut microbiota, fat synthesis and muscle quality of SPF grade Kunming mice. Three housing densities were accomplished by raising different mice per cage with the same floor size. Kunming mice were reared at low stocking density (LSD, three mice a group), medium stocking density (MSD, 5 mice a group), and high stocking density (HSD, 10 mice a group) for 12 weeks. The results demonstrated that the stocking density affected intestinal microbial flora composition. We found that compared with the MSD group, the abundance of Lactobacillus in the LSD group and the HSD group decreased, but the abundance of unclassified_Porphyromonadaceae increased. Moreover, fat synthesis and muscle quality were linked to the intestinal microbial flora and stocking density. Compared with the LSD group and the HSD group, the MSD group had a more balanced gut flora, higher fat synthesis and higher muscle quality. Overall, this study demonstrated that stocking density could affect gut microbiota composition, and reasonable stocking density could improve fat synthesis and muscle quality. Our study will provide theoretical support for the suitable stocking density of laboratory animals.

11.
Front Pediatr ; 9: 722885, 2021.
Article in English | MEDLINE | ID: mdl-34650942

ABSTRACT

Background: Jilin Province, located in northeastern China, recently experienced a human adenovirus (HAdV) epidemic. Few studies involving hospitalized pediatric patients with pneumonia caused by HAdV in our region exist. HAdV pneumonia can lead to severe long-term respiratory sequelae, such as post-infectious bronchiolitis obliterans (PIBO), which has a poor prognosis and greatly influences the quality of life of pediatric patients. However, studies on the risk factors for PIBO are limited. Objective: To describe the HAdV pneumonia prevalence and determine potential risk factors for PIBO development among hospitalized children in Jilin Province, China. Methods: The data of 187 children with HAdV pneumonia (10 months-12 years old) admitted to the First Hospital of Jilin University during an outbreak between October 2018 and January 2020 were retrospectively studied. We analyzed the epidemiological characteristics of HAdV pneumonia, focusing on severe HAdV pneumonia (66 cases). The risk factors for BO development were determined by comparing the demographic and clinical data of the BO and non-BO groups. Results: The largest number of HAdV pneumonia cases occurred in January 2019 (severe n = 18, general n = 21), followed by December 2018 (severe n = 14, general n = 11), June 2019 (general n = 17), July 2019 (general, n = 14), and May 2019 (general, n = 13). In total, 91.98% of the children with HAdV pneumonia were <6 years old (172/187), and 50% of the pediatric patients with severe HAdV pneumonia were <2 years old (33/66). We found that 30.3% of the severe cohort developed BO (20/66), and the strongest independent risk factors for PIBO were persistent wheezing (OR 181.776, 95% CI, 3.385-9,761.543) and acute respiratory failure (OR 51.288, 95% CI, 1.858-1,415.441) during a severe pneumonia episode. Conclusions: The largest number of HAdV pneumonia cases, especially severe cases, occurred in winter in Northeast China, followed by summer. The majority of children admitted with HAdV pneumonia were <6 years old, and half of severe HAdV pneumonia patients were <2 years old. Children who had persistent wheezing or acute respiratory failure during the acute phase of severe HAdV pneumonia were prone to the development of BO.

12.
Nanomaterials (Basel) ; 11(11)2021 Nov 16.
Article in English | MEDLINE | ID: mdl-34835848

ABSTRACT

As one of the important technologies in the field of heterogeneous integration, transfer technology has broad application prospects and unique technical advantages. This transfer technology includes the wet chemical etching of a sacrificial layer, such that silicon nano-film devices are released from the donor substrate and can be transferred. However, in the process of wet etching the SiO2 sacrificial layer present underneath the single-crystal silicon nano-film by using the transfer technology, the etching is often incomplete, which seriously affects the efficiency and quality of the transfer and makes the device preparation impossible. This article analyzes the principle of incomplete etching, and compares the four factors that affect the etching process, including the size of Si nano-film on top of the sacrificial layer, the location of the anchor point, the shape of Si nano-film on top of the sacrificial layer, and the thickness of the sacrificial layer. Finally, the etching conditions are obtained to avoid the phenomenon of incomplete etching of the sacrificial layer, so that the transfer technology can be better applied in the field of heterogeneous integration. Additionally, Si MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors) on sapphire substrate were fabricated by using the optimized transfer technology.

13.
Bioengineered ; 11(1): 1058-1070, 2020 12.
Article in English | MEDLINE | ID: mdl-33016225

ABSTRACT

Serine protease Omi/HtrA2, a member of the HtrA family, is closely related to the maintenance of mitochondrial integrity and participates in apoptosis but its role in cerebral ischemia/reperfusion (I/R) injury and cellular oxidative stress response remains unclear. In this study, we found that I/R injury resulted in a time-dependent increase in Omi/HtrA2 expression in rat brain tissue. Inhibition of Omi/HtrA2 significantly inhibited XIAP cleavage in H2O2-induced PC12 cells. In addition, inhibition of Omi/HtrA2 significantly inhibited the up-regulation of mitochondrial stress proteins CHOP and ClpP, significantly reduced mitochondrial aggregation, and attenuated the decline of mitochondrial ΔΨm in PC12 cells. Studies show that there is a physical interaction between Omi/HtrA2 and OPA1. We found that Omi/HtrA2 and OPA1 are closely related to the oxidative stress mitochondrial response in PC12 cells. The current study has demonstrated that Omi/HtrA2 is upregulated in brain I/R injury in vivo and is implicated in mitochondrial response to oxidative stress in vitro by regulating mitochondrial stress proteins CHOP and CLpP and by interacting with mitochondrial cristae remodeling protein OPA1. These findings suggest that Omi/HtrA2 could be a candidate molecular target in diseases that involve oxidative stress such as in I/R injury. Abbreviation: ATP: Adenosine tripHospHate; Bax: BCL2-Associated X; Bcl-2: B-cell lympHoma-2; BSA: Albumin from bovine serum; DMEM: Dulbecco's Minimum Essential Medium; DMSO: Dimethyl sulfoxide; HSP60: Heat shock protein60, 70; L-OPA1: Long forms of OPA1; Omi/HtrA2: high-temperature-regulated A2; MCAO: Middle cerebral artery occlusion; OPA1: Optic AtropHy; PBS: PHospHate buffered saline; PMSF: pHenylmethyl sulfonylfluoride; ROS: reactive oxygen species; SDS: Sodium dodecyl sulfate; S-OPA1: Short forms of OPA1; TTC: TripHenyltetrazalium chloride; XIAP: X-linked inhibitor apoptosis protein.


Subject(s)
GTP Phosphohydrolases/metabolism , High-Temperature Requirement A Serine Peptidase 2/metabolism , Mitochondrial Proteins/metabolism , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Transcription Factor CHOP/metabolism , Animals , Apoptosis/physiology , GTP Phosphohydrolases/genetics , High-Temperature Requirement A Serine Peptidase 2/genetics , Hydrogen Peroxide/pharmacology , Male , Mitochondria/metabolism , Mitochondrial Dynamics/genetics , Mitochondrial Dynamics/physiology , Mitochondrial Proteins/genetics , Oxidative Stress/physiology , PC12 Cells , Rats , Rats, Wistar , Reactive Oxygen Species/metabolism , Transcription Factor CHOP/genetics
14.
Materials (Basel) ; 13(10)2020 May 19.
Article in English | MEDLINE | ID: mdl-32438627

ABSTRACT

Optical microcavity configuration is one optical strategy to enhance light trapping in devices using planar electrodes. In this work, the potential application of optical microcavity configuration with ultrathin metal electrodes in highly efficient perovskite solar cells (PSCs) was investigated. By comparing with the device with conventional indium-tin-oxide (ITO) electrodes, it is shown that by carefully designing the Ag/dielectric planar electrode, a device with an optical microcavity structure can achieve comparable-or even higher-power conversion efficiency than a conventional device. Moreover, there is a relative high tolerance for the Ag film thickness in the optical microcavity structure. When the thickness of the Ag film is increased from 8 to 12 nm, the device still can attain the performance level of a conventional device. This gives a process tolerance to fabricate devices with an optical microcavity structure and reduces process difficulty. This work indicates the great application potential of optical microcavities with ultrathin metal electrodes in PSCs; more research attention should be paid in this field.

15.
Nanomaterials (Basel) ; 10(7)2020 Jul 06.
Article in English | MEDLINE | ID: mdl-32640591

ABSTRACT

The inorganic perovskite has a better stability than the hybrid halide perovskite, and at the same time it has the potential to achieve an excellent photoelectric performance as the organic-inorganic hybrid halide perovskite. Thus, the pursuit of a low-cost and high-performance inorganic perovskite solar cell (PSC) is becoming the research hot point in the research field of perovskite devices. In setting out to build vacuum-free and carbon-based all-inorganic PSCs with the traits of simple fabrication and low cost, we propose the ones with a simplified vertical structure of FTO/CsPbIBr2/carbon upon interfacial modification with PEI species. In this structure, both the electron-transporting-layer and hole-transporting-layer are abandoned, and the noble metal is also replaced by the carbon paste. At the same time, FTO is modified by PEI, which brings dipoles to decrease the work function of FTO. Through our measurements, the carrier recombination has been partially suppressed, and the performance of champion PSCs has far exceeded the control devices without PEI modification, which yields a power conversion efficiency of 4.9% with an open circuit voltage of 0.9 V and a fill factor of 50.4%. Our work contributes significantly to give an available method to explore charge-transporting-layer-free, low-cost, and high-performance PSCs.

16.
ACS Appl Mater Interfaces ; 12(5): 6607-6614, 2020 Feb 05.
Article in English | MEDLINE | ID: mdl-31927909

ABSTRACT

Self-powered photodetectors (PDs) with inorganic lead halide perovskites hold multiple traits of high sensitivity, fast response, independence from external power supply, and excellent sustainability and stability, thus holding a great promise for practical applications. However, they generally contain high-temperature-processed electron-transporting layers (ETLs) and high-cost, unstable hole-transporting layers (HTLs) coupled with noble metal electrodes, which bring significant obstacles of production cost and stability for their potential commercialization. Herein, we demonstrate the building of high-performance HTL/ETL-free, self-powered CsPbIBr2 PD with simplified architecture of fluorine-doped tin oxide (FTO)/CsPbIBr2/carbon upon interfacial modification by polyethyleneimine (PEI). The optimized PD yields a dark current of 2.03 × 10-9 A, peak responsivity (R) of 0.32 A/W, maximum specific detectivity (D*) of 3.74 × 1012 Jones, and response time of 1.21 µs. These figures of merit are far beyond those of the one prepared without PEI modification and even the PD containing TiO2 ETL. Hence, our work suggests a highly feasible route to develop self-powered PDs with significantly simplified fabrication and a reduced production cost.

17.
Polymers (Basel) ; 10(7)2018 Jul 02.
Article in English | MEDLINE | ID: mdl-30960650

ABSTRACT

In this work, an efficient inverted organic solar cell (OSC) based on the non-fullerene PBDB-T:IT-M blend system is demonstrated by using an aqueous solution processed ZnO electron-selective layer with the whole process temperature ≤150 °C and a thermally evaporated MoO3 hole-selective layer The ZnO selective layer is deposited by aqueous solution and prepared in a low-temperature process, so that it can be compatible with the roll-to-roll process. The proposed device achieves an enhanced power conversion efficiency (PCE) of 9.33% compared with the device based on the high-temperature sol-gel-processed ZnO selective layer, which achieves a PCE of 8.62%. The inverted device also shows good stability, keeping more than 82% of its initial PCE after being stored under ambient air conditions and a humidity of around 40% without any encapsulation for 240 h. The results show the potential for the fabrication of efficient non-fullerene OSCs with low-temperature metal oxide selective layers.

19.
Acta Trop ; 152: 215-219, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26384456

ABSTRACT

This cross-sectional study was aimed to investigate the Toxocara serology in children in Shandong and Jilin provinces, China using an enzyme-linked immunosorbent assay (ELISA). The overall Toxocara seroprevalence among the study population (n=1458) was 19.3%, sick children (26.4%) had significantly higher seroprevalence than clinically healthy children (14.4%) (P<0.05), and the highest Toxocara seroprevalence was found in children suffering from chronic cough (40.6%), followed by recurrent abdominal pain (40.0%), recurrent headache (38.1%), slight fever (36.2%), and recurrent vomiting (31.6%). Place of residence, education level, type of school, keeping dogs at home, contact with dogs and cats and exposure with soil were found to be associated with Toxocara infection. Our findings show that children infection with Toxocara is common in Shandong and Jilin provinces, eastern and northeastern China, indicating an immediate need for implementing strategies and measures to prevent and control Toxocara infection in children in China.


Subject(s)
Toxocariasis/epidemiology , Adolescent , Animals , Cats , Child , Child, Preschool , China/epidemiology , Cross-Sectional Studies , Dogs , Female , Humans , Infant , Male , Risk Factors , Seroepidemiologic Studies , Toxocariasis/etiology , Toxocariasis/prevention & control
20.
Int J Infect Dis ; 30: 33-5, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25461653

ABSTRACT

OBJECTIVE: Infection by the protozoan parasite Toxoplasma gondii is generally prevalent in animals and humans worldwide. However, little is known about T. gondii infection among children in China. Thus, the present study was conducted to detect the seroprevalence of T. gondii infection and estimate associated risk factors among children in eastern China. METHODS: A cross-sectional study of 1500 children from three cities (Changchun, Qingdao, Weihai) was conducted between May 2013 and July 2014 to estimate the seroprevalence and potential risk factors associated with acquiring T. gondii infection in children in China. Demographic and blood samples were collected, and anti-T. gondii IgG and IgM antibodies were measured by ELISA. RESULTS: The mean age of the 1500 children participating in the study was 9.03 years (range 1-18). The overall seroprevalence of Toxoplasma infection was 15.13%, of which 13.13% were positive for only anti-Toxoplasma IgG antibodies, 3.13% were positive for both anti-Toxoplasma IgG and IgM antibodies and 2.00% were IgM positive and IgG negative. Moreover, raising cats at home (OR=1.94, 95% CI=1.288-2.912, P=0.002) and hand washing habits (OR=0.38, 95% CI=0.230-0.635, P<0.001) were estimated to be risk and protective factors associated with Toxoplasma seroprevalence, respectively. CONCLUSIONS: The present study revealed for the first time that children's infection with T. gondii is common in eastern China. The present data indicate a need to implement methods of prevention and control measures against Toxoplasma infection in China.


Subject(s)
Toxoplasma/immunology , Toxoplasmosis/epidemiology , Adolescent , Animals , Antibodies, Protozoan/blood , Child , Child, Preschool , China , Cities , Cross-Sectional Studies , Female , Humans , Immunoglobulin G/blood , Infant , Male , Risk Factors , Seroepidemiologic Studies
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