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Chlorella contains a variety of polysaccharides with complex composition and structure, which are composed of various monosaccharides such as galactose, rhamnose, glucose, arabinose, mannose, xylose and glucuronic acid. The glycosidic linkages of polysaccharides are diverse, including α-1,6-glucose, β-1,3-galactose, α-1,6-galactose, α-1,3-rhamnose, α-1,2-rhamnose, α-1,5-arabinose, α-1,6-mannose and β-1,4-xylose. Some polysaccharides are modified by methylation, sulfation and acetylation. Meanwhile, many studies have shown that polysaccharides have multiple functions such as immunoregulatory, anti-inflammatory, antioxidant, anti-tumor, antibacterial and intestinal flora-regulatory effects. At present, monosaccharide composition analysis, methylation combined with gas chromatography-mass spectrometry (GC-MS) and two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy are mainly used for research on the structure of chlorella polysaccharides such as analysis of monosaccharide composition, glycosidic bond types, branch chain substitution positions and branch chain types. This review hopes to provide valuable information for the fine structural analysis and structure-activity relationship study of polysaccharides from Chlorella.

Aims: Heritable dilated cardiomyopathy (DCM) or DCM associated with congenital or acquired left ventricular diseases carries a significant mortality risk. Pulmonary artery banding (PAB) has been proposed as an alternative to heart transplantation. This study aimed to delineate the clinical development, ventricular reverse remodelling, and functional regeneration of the dilated left ventricle, presenting as a pioneering approach in China. Methods and results: This prospective study was initiated in November 2021, involving paediatric patients with a significant dilated left ventricle and preserved right ventricle who underwent surgical PAB. The baseline characteristics and clinical information during follow‐up were collected. Seven patients (five boys) with a median age of 240 (148, 1028) days have been included thus far. No procedural or follow‐up mortality was observed. The modified Ross functional class improved from treatment to follow‐up of 348 (200, 629) days, and the median left ventricular ejection fraction increased from 27.0 (15.0, 34.0) % before surgery to 61.0 (52.0, 68.0) % (P < 0.05); the median left ventricular end‐diastolic diameter and corresponding Z‐scores decreased from 43.0 (40.0, 55.0) mm [+9.4 (+7.7, +11.7)] to 33.0 (29.0, 39.0) mm [+1.8 (+1.3, +3.8)] (P < 0.05). Functional regeneration of the left ventricle was observed in five patients. Three of them underwent balloon dilation of the PAB to relieve excessively elevated right ventricular pressures. Conclusions: The application of PAB should adhere to strict criteria. Initial results are promising for infants and even toddlers with a dilated left ventricle and limited probability of spontaneous recovery. PAB can be an alternative when there is a shortage of donor transplants and assist devices, especially for low‐ and middle‐income countries. [ABSTRACT FROM AUTHOR]

Objective To analyze the epidemiological characteristics of a local outbreak of dengue fever caused by a construction site in Shenzhen City, evaluate the effectiveness of control measures, and explore dengue fever prevention and control strategies suitable for local characteristics. Methods Epidemiological investigations were conducted on dengue fever cases during the outbreak. Descriptive analysis methods were used to analyze the epidemiological characteristics of the outbreak. The Breteau Index method and double-layer trap method were employed to monitor mosquito density and evaluate the effectiveness of control measures. Results A total of 85 cases were reported in this outbreak, all of which were local cases. Among them, 76 cases (89.41%) were laboratory-confirmed, and 9 cases (10.59%) were clinically diagnosed. All laboratory-confirmed cases were identified as Dengue Virus Serotype 1 (DENV-1). There were 64 male and 21 female cases, with no critical or fatal cases. The age of cases ranged from 4 to 78 years old, with the highest number of cases occurring in the 31-<50 age group (43 cases, 50.59%). The majority of cases were construction workers (38 cases, 44.71%). The outbreak was mainly concentrated in Qiutou Community, Fu Hai Street, Bao'an District, accounting for 69 cases (81.18%). The median and quartile M (P25, P75) interval between onset of illness and diagnosis was 3 (2, 5) days, with construction workers having a shorter interval between onset and seeking medical attention compared to other residents. After implementing control measures such as case search, isolation and treatment, mosquito control, cleaning of mosquito breeding sites, and health education, the daily average Breteau Index decreased from the initial 12 to below 3, and the adult mosquito density remained at 0 mosquitoes (person/hour). Conclusions This outbreak was a local dengue fever outbreak initiated at a construction site. After the community staff participated in the comprehensive prevention and control measures, including case searching, mosquito elimination, clearing of breeding grounds, environmental health inspection, and education and propaganda, the epidemic was effectively contained. In addition, the continuous improvement of clinicians' diagnostic levels for dengue fever and the popularization of dengue fever antigen primary screening reagents (NS1 antigen reagents) in medical institutions may have played a crucial role in the early detection of the epidemic. [ABSTRACT FROM AUTHOR]

To comprehensively understand temperature and moisture changes in a continuous microwave rice grain drying system, this study proposes a simulation strategy that facilitates the continuous movement of rice grains. The study establishes a three‐dimensional model concerning multiple physical fields, including electromagnetism, heat, and mass transfer. It examines the effects of rice grain layer thickness and microwave intensity on the moisture and temperature of rice grains. The results indicate that the drying rate is negatively correlated with material thickness but positively correlated with temperature. The optimal thickness for the rice grain layer is 8 mm. Furthermore, both the microwave drying rate and temperature increase with microwave intensity. These findings contribute to a deeper understanding of the hydrothermal change mechanisms in rice grains during microwave drying. Practical applications: Microwave drying, as an emergent drying technology, has garnered widespread attention for its selective heating, efficient drying, energy savings, and environmental protection. Nevertheless, enhancing uniformity during the microwave heating process constitutes an important research topic in scientific research and technological applications. Numerical simulation methods can visually analyze electric field distribution, thereby optimizing microwave heating uniformity and improving drying effects. This article aims to accurately predict the continuous microwave drying time of paddy and maximize energy usage by optimizing drying thickness and microwave power parameters establishing a mathematical model for the process. The study not only provides a solid theoretical basis for microwave dryer design but also scientifically guides the continuous microwave drying of rice and other food crops. [ABSTRACT FROM AUTHOR]

Regioselective benzanilide bromination that generates either regioisomer from the same starting material is desirable. Herein, we develop switchable site-selective C(sp2)-H bromination by promoter regulation. This protocol leads to regiodivergent brominated benzanilide starting from the single substrate via selection of promoters. The protocol demonstrates excellent regioselectivity and good tolerance of functional groups with high yields. The utility effectiveness of this method has been well exemplified in the late-stage modification of biologically important molecules. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is the leading cause of acute viral hepatitis worldwide. HEV RNA detection is the gold standard for HEV infection diagnosis and PCR methods are commonly used but are usually time-consuming and expensive, resulting in low detection efficiency and coverage, especially in low-income areas. Here, we developed a simpler and more accessible HEV RNA detection method based on CRISPR-Cas13a system. A total of 265 samples of different types and sources, including 89 positive samples and 176 negative samples, were enrolled for evaluations. The sensitivity and specificity of the Cas13a-crRNA detection system were evaluated. The World Health Organization reference panel for HEV genotypes was used to evaluate the capability for detecting different HEV genotypes. The validity of the assay was compared with RT-qPCR. The 95 % limits of detection (LOD) of Cas13a-crRNA-based fluorescence assay and strip assay were 12.5 and 200 IU/mL, respectively. They did not show cross-reactivity with samples positive for hepatitis A virus, hepatitis B virus, hepatitis C virus, coxsackievirus A16, rotavirus, enterovirus 71, norovirus or enteropathic Escherichia coli. Different HEV genotypes (HEV1–4) can be detected by the assay. Compared to RT-qPCR, the positive predictive agreements of Cas13a-crRNA-based fluorescence and strip assay were 98.9 % (95 % CI: 93.9–99.8 %) and 91.0 % (95 % CI: 83.3–95.4 %), respectively. The negative predictive agreements were both 100 % (95 % CI: 97.8–100 %). In conclusion, we established a rapid and convenient HEV RNA detection method with good sensitivity and specificity based on CRISPR-Cas13a system, providing a new option for HEV infection diagnosis. [ABSTRACT FROM AUTHOR]