58 research outputs found

    A High Quality and Quantity Hybrid Perovskite Quantum Dots (CsPbX\u3csub\u3e3\u3c/sub\u3e, X= Cl, Br and I) Powders Synthesis via Ionic Displacement

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    Recently, all-inorganic perovskites CsPbX3 (X= Cl, Br and I) quantum dots (QDs) have drawn great attentions because of their PL spectra tunable over the whole visible spectral region (400-700 nm) and adjustable bandgap, which revealed a promising potential on the field of photoelectronic devices, such as solar cells, LEDs and sensors. In this paper, CsPbX3 QDs and hybrid QDs, CsPbClxBr3-x and CsPbBrxI3-x were synthesized via one-step and two-step methods comparably. The optical bandgaps of CsPbCl3, CsPbBr3, and CsPbI3, were calculated as 3.08, 2.36, and 1.73eV, respectively, based on the Tauc\u27s equation and UV absorption spectra. Ionic displacement and phase transformation occurred during the mixing process were found based on the monitoring of PL spectra and HRTEM characterization. The long-term stability, dried, high quality and two-dimensional hybrid CsPbBrxI3-x QDs powders could be achieved via the two-step method. Polar solution inductions were used to wash and purify the CsPbX3 QDs, which help obtain of various compositions and well crystallize all-inorganic perovskites QDs powders

    Measuring the contribution of the ocean: A comparison of the statistical classification of the marine economy used by China and Canada

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    Most of the major marine countries share an identical knowledge about marine economy. Ocean-related principle is the primary principles which distinguish the ocean economy from national economy and other economies. The understandings of marine economy from various countries all take into consideration the ocean-relativeness character geographically or industrially. However, there are certain differences in statistical frameworks and specific industrial classifications. In this paper, the statistical classification of marine economy between China and Canada is comparatively studied from the perspectives of the connotation of marine economy, the classification of regional statistics, and the classification of industrial statistics. Moreover, the identification of the statistical calibers of the two countries’ marine economy is further analyzed. This allows for a comparison of the statistical data between the two countries’ marine economy. Several suggestions on enforcing the statistical work for the marine economy are proposed in the end

    Decomposition of Microbial Necromass Is Divergent at the Individual Taxonomic Level in Soil

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    The turnover of microbial biomass plays an important part in providing a significant source of carbon (C) to soil organic C. However, whether the decomposition of microbial necromass (non-living microbial biomass) in the soil varies at the individual taxa level remains largely unknown. To fill up these gaps, we compared the necromass decomposition of bacterial and archaeal taxa by separating live microbial biomass with 18O-stable isotope probing from dead microbial biomass in soil. Our results showed that most of the microbial necromass at the operational taxonomic unit level (88.51%), which mainly belong to Acidobacteria, Actinobacteria, Gemmatimonadetes, and Proteobacteria, decomposed significantly after 30 days. In addition, there were great variations in necromass decomposition within each phylum, such as the decomposition of operational taxonomic units in Proteobacteria that ranged from 51% (Beijerinckia) to 92% (Nitrosospira). More importantly, the necromass decomposition was not related to the chemical composition of the cell wall but might positively correlate with the guanine–cytosine content of DNA and negatively correlated with genome size. This study provided a new insight that the decomposition of microbial necromass in soil was divergent at the individual taxonomic level and could not be fully explained by previously proposed mechanisms

    The Research Value of Biphasic Registration Quantitative Computed Tomography Emphysema Index in the Evaluation of Mild to Moderate COPD

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    Objective: To find the optimal quantitative index of emphysema by comparing and analyzing the quantitative indexes of emphysema in patients with mild to moderate chronic obstruction pulmonary disease (COPD) via registered biphasic quantitative computed tomography (QCT). Methods: We retrospectively collected 55 healthy controls, 21 Global Initiative for Chronic Obstructive Pulmonary Disease (GOLD) 1 case, and 31 GOLD 2 cases in our hospital. We imported the CT raw DICOM data into the "Digital Lung" analysis platform and measured the LAA-950% at the end of deep inspiration and the LAA-910% at the end of deep expiration. The expiratory and inspiratory CT images were registered. Then, the percentage of emphysema area (PRMEmph%), the percentage of functional small airway disease area (PRMfSAD%), and the percentage of the normal area (PRMNormal%) were calculated according to the threshold method. Pulmonary function indicators included FVC, FEV1%, and FEV1/FVC. Differences in general data, CT quantitative indexes, and pulmonary function between groups were assessed using the independent sample t-test, Mann–Whitney U test, or chi-square test, and the correlation was analyzed using Spearman correlation. The receiver operating characteristic (ROC) curve was drawn to analyze the diagnostic performance of CT quantitative parameters for emphysema in patients with mild to moderate COPD. Results: There were significant differences in sex, smoking index, FEV1%, FEV1/FVC, inspiratory phase LAA%-950, expiratory phase LAA%-910, PRMEmph%, PRMfSAD%, and PRMNormal% between the mild to moderate COPD patients and normal control groups. The inspiratory phase LAA%-950 was negatively correlated with FEV1/FVC, the expiratory phase LAA%-910 and PRMEmph% were negatively correlated with FVC, FEV1%, and FEV1/FVC. ROC curve analysis results showed that the areas under the curve of inspiration phase LAA%-950, expiratory phase LAA%-910, and PRMEmph% were 0.742, 0.861, and 0.876, respectively. Among them, the area under the curve of the PRMEmph% index was the largest, with a corresponding critical value of 9.84%, a sensitivity of 76.90%, and a specificity of 94.50%. Conclusion: Quantitative CT emphysema index LAA%-950 in the inspiratory phase, LAA%-910 in the expiratory phase, and PRMEmph% in biphasic can objectively evaluate emphysema in patients with mild to moderate COPD, among which PRMEmph% is the best evaluation index

    Facile Synthesis of Monodisperse CdS Nanocrystals via Microreaction

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    CdS-based nanocrystals (NCs) have attracted extensive interest due to their potential application as key luminescent materials for blue and white LEDs. In this research, the continuous synthesis of monodisperse CdS NCs was demonstrated utilizing a capillary microreactor. The enhanced heat and mass transfer in the microreactor was useful to reduce the reaction temperature and residence time to synthesize monodisperse CdS NCs. The superior stability of the microreactor and its continuous operation allowed the investigation of synthesis parameters with high efficiency. Reaction temperature was found to be a key parameter for balancing the reactivity of CdS precursors, while residence time was shown to be an important factor that governs the size and size distribution of the CdS NCs. Furthermore, variation of OA concentration was demonstrated to be a facile tuning mechanism for controlling the size of the CdS NCs. The variation of the volume percentage of OA from 10.5 to 51.2% and the variation of the residence time from 17 to 136 s facilitated the synthesis of monodisperse CdS NCs in the size range of 3.0–5.4 nm, and the NCs produced photoluminescent emissions in the range of 391–463 nm

    Synthesis of Monodisperse Nanocrystals via Microreaction: Open-to-Air Synthesis with Oleylamine as a Coligand

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    Microreaction provides a controllable tool to synthesize CdSe nanocrystals (NCs) in an accelerated fashion. However, the surface traps created during the fast growth usually result in low photoluminescence (PL) efficiency for the formed products. Herein, the reproducible synthesis of highly luminescent CdSe NCs directly in open air was reported, with a microreactor as the controllable reaction tool. Spectra investigation elucidated that applying OLA both in Se and Cd stock solutions could advantageously promote the diffusion between the two precursors, resulting in narrow full-width-at-half maximum (FWHM) of PL (26 nm). Meanwhile, the addition of OLA in the source solution was demonstrated helpful to improve the reactivity of Cd monomer. In this case, the focus of size distribution was accomplished during the early reaction stage. Furthermore, if the volume percentage (vol.%) of OLA in the precursors exceeded a threshold of 37.5%, the resulted CdSe NCs demonstrated long-term fixing of size distribution up to 300 s. The observed phenomena facilitated the preparation of a size series of monodisperse CdSe NCs merely by the variation of residence time. With the volume percentage of OLA as 37.5% in the source solution, a 78 nm tuning of PL spectra (from 507 to 585) was obtained through the variation of residence time from 2 s to 160 s, while maintaining narrow FMWH of PL (26–31 nm) and high QY of PL (35–55%)

    Phenomic analysis of chronic granulomatous disease reveals more severe integumentary infections in X-Linked compared with autosomal recessive chronic granulomatous disease

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    BACKGROUND : Chronic granulomatous disease (CGD) is an inborn error of immunity (IEI), characterised by recurrent bacterial and fungal infections. It is inherited either in an Xlinked (XL) or autosomal recessive (AR) mode. Phenome refers to the entire set of phenotypes expressed, and its study allows us to generate new knowledge of the disease. The objective of the study is to reveal the phenomic differences between XL and AR-CGD by using Human Phenotype Ontology (HPO) terms. METHODS : We collected data on 117 patients with genetically diagnosed CGD from Asia and Africa referred to the Asian Primary Immunodeficiency Network (APID network). Only 90 patients with sufficient clinical information were included for phenomic analysis. We used HPO terms to describe all phenotypes manifested in the patients. RESULTS : XL-CGD patients had a lower age of onset, referral, clinical diagnosis, and genetic diagnosis compared with AR-CGD patients. The integument and central nervous system were more frequently affected in XL-CGD patients. Regarding HPO terms, perianal abscess, cutaneous abscess, and elevated hepatic transaminase were correlated with XL-CGD. A higher percentage of XL-CGD patients presented with BCGitis/BCGosis as their first manifestation. Among our CGD patients, lung was the most frequently infected organ, with gastrointestinal system and skin ranking second and third, respectively. Aspergillus species, Mycobacterium bovis, and Mycobacteirum tuberculosis were the most frequent pathogens to be found. CONCLUSION : Phenomic analysis confirmed that XL-CGD patients have more recurrent and aggressive infections compared with AR-CGD patients. Various phenotypic differences listed out can be used as clinical handles to distinguish XL or AR-CGD based on clinical features.The Society for Relief of Disabled Children and Jeffrey Modell Foundation.https://www.frontiersin.org/journals/immunologydm2022Paediatrics and Child Healt

    Targeted gene sanger sequencing should remain the first-tier genetic test for children suspected to have the five common X-linked inborn errors of immunity

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    DATA AVAILABILITY STATEMENT : The original contributions presented in the study are included in the article/Supplementary Material. Further inquiries can be directed to the corresponding author.To address inborn errors of immunity (IEI) which were underdiagnosed in resource-limited regions, our centre developed and offered free genetic testing for the most common IEI by Sanger sequencing (SS) since 2001. With the establishment of The Asian Primary Immunodeficiency (APID) Network in 2009, the awareness and definitive diagnosis of IEI were further improved with collaboration among centres caring for IEI patients from East and Southeast Asia. We also started to use whole exome sequencing (WES) for undiagnosed cases and further extended our collaboration with centres from South Asia and Africa. With the increased use of Next Generation Sequencing (NGS), we have shifted our diagnostic practice from SS to WES. However, SS was still one of the key diagnostic tools for IEI for the past two decades. Our centre has performed 2,024 IEI SS genetic tests, with in-house protocol designed specifically for 84 genes, in 1,376 patients with 744 identified to have disease-causing mutations (54.1%). The high diagnostic rate after just one round of targeted gene SS for each of the 5 common IEI (X-linked agammaglobulinemia (XLA) 77.4%, Wiskott–Aldrich syndrome (WAS) 69.2%, X-linked chronic granulomatous disease (XCGD) 59.5%, X-linked severe combined immunodeficiency (XSCID) 51.1%, and X-linked hyper-IgM syndrome (HIGM1) 58.1%) demonstrated targeted gene SS should remain the first-tier genetic test for the 5 common X-linked IEI.The Hong Kong Society for Relief of Disabled Children and Jeffrey Modell Foundation.http://www.frontiersin.org/Immunologyam2023Paediatrics and Child Healt
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