Trends in respiratory diseases before and after the COVID-19 pandemic in China from 2010 to 2021.

BACKGROUND: The ongoing benefits of coronavirus disease 2019 (COVID-19) nonpharmaceutical interventions (NPIs) for respiratory infectious diseases in China are still unclear. We aimed to explore the changes in seven respiratory infectious diseases before, during, and after COVID-19 in China from 2010 to 2021. METHODS: The monthly case numbers of seven respiratory infectious diseases were extracted to construct autoregressive integrated moving average (ARIMA) models. Eight indicators of NPIs were chosen from the COVID-19 Government Response Tracker system. The monthly case numbers of the respiratory diseases and the eight indicators were used to establish the Multivariable generalized linear model (GLM) to calculate the incidence rate ratios (IRRs). RESULTS: Compared with the year 2019, the percentage changes in 2020 and 2021 were all below 100% ranging from 3.81 to 84.71%. Pertussis and Scarlet fever started to increase in 2021 compared with 2020, with a percentage change of 183.46 and 171.49%. The ARIMA model showed a good fit, and the predicted data fitted well with the actual data from 2010 to 2019, but the predicted data was bigger than the actual number in 2020 and 2021. All eight indicators could negatively affect the incidence of respiratory diseases. The seven respiratory diseases were significantly reduced during the COVID-19 pandemic in 2020 and 2021 compared with 2019, with significant estimated IRRs ranging from 0.06 to 0.85. In the GLM using data for the year 2020 and 2021, the IRRs were not significant after adjusting for the eight indicators in multivariate analysis. CONCLUSION: Our study demonstrated the incidence of the seven respiratory diseases decreased rapidly during the COVID-19 pandemic in 2020 and 2021. At the end of 2021, we did see a rising trend for the seven respiratory diseases compared to the year 2020 when the NPIs relaxed in China, but the rising trend was not significant after adjusting for the NPIs indicators. Our study showed that NPIs have an effect on respiratory diseases, but Relaxation of NPIs might lead to the resurgence of respiratory diseases.

A prediction model for COVID-19 liver dysfunction in patients with normal hepatic biochemical parameters.

Coronavirus disease 2019 (COVID-19) patients with liver dysfunction (LD) have a higher chance of developing severe and critical disease. The routine hepatic biochemical parameters ALT, AST, GGT, and TBIL have limitations in reflecting COVID-19-related LD. In this study, we performed proteomic analysis on 397 serum samples from 98 COVID-19 patients to identify new biomarkers for LD. We then established 19 simple machine learning models using proteomic measurements and clinical variables to predict LD in a development cohort of 74 COVID-19 patients with normal hepatic biochemical parameters. The model based on the biomarker ANGL3 and sex (AS) exhibited the best discrimination (time-dependent AUCs: 0.60-0.80), calibration, and net benefit in the development cohort, and the accuracy of this model was 69.0-73.8% in an independent cohort. The AS model exhibits great potential in supporting optimization of therapeutic strategies for COVID-19 patients with a high risk of LD. This model is publicly available at https://xixihospital-liufang.shinyapps.io/DynNomapp/.

Perovskite grain wrapping by converting interfaces and grain boundaries into robust and water-insoluble low-dimensional perovskites.

Stabilizing perovskite solar cells requires consideration of all defective sites in the devices. Substantial efforts have been devoted to interfaces, while stabilization of grain boundaries received less attention. Here, we report on a molecule tributyl(methyl)phosphonium iodide (TPI), which can convert perovskite into a wide bandgap one-dimensional (1D) perovskite that is mechanically robust and water insoluble. Mixing TPI with perovskite precursor results in a wrapping of perovskite grains with both grain surfaces and grain boundaries converted into several nanometer-thick 1D perovskites during the grain formation process as observed by direct mapping. The grain wrapping passivates the grain boundaries, enhances their resistance to moisture, and reduces the iodine released during light soaking. The perovskite films with wrapped grains are more stable under heat and light. The best device with wrapped grains maintained 92.2% of its highest efficiency after light soaking under 1-sun illumination for 1900 hours at 55°C open-circuit condition.

Frequency dependence of the ultrasonic power reflected from the water-tissue interface of human cancellous bone in vitro.

Numerous studies have performed in vitro ultrasonic measurements of cancellous bone in water to develop techniques for ultrasonic bone assessment. Because cancellous bone is a highly porous medium, ultrasonic reflections at the water-bone interface may be frequency dependent. The goal of this study was to investigate the effect of porosity on the frequency dependence of the reflected power. Ultrasonic measurements were performed in a water tank at room temperature on 15 specimens of cancellous bone prepared from the proximal end of 9 human femurs using single element, broadband transducers with center frequencies of 3.5, 5, 7.5, and 10 MHz. Power spectra of pulses reflected from the water-specimen interface were corrected for the frequency response of the measurement system to obtain the reflected power in decibels R^dB(f). To suppress random phase cancellation effects, R^dB(f) was averaged over multiple sites on multiple specimens. A frequency dependence of R^dB(f) was observed in the 2.6-10 MHz range. The frequency dependence was moderate, with a maximum change of less than 6 dB over the entire frequency range. R^dB(f) was greatest for low porosity specimens. The frequency averaged intensity reflection coefficient ranged from 7.4 × 10^-4 to 7.8 × 10^-3 for high and low porosity specimen groups, respectively.

Bifacial all-perovskite tandem solar cells.

The efficiency of all-perovskite tandem devices falls far below theoretical efficiency limits, mainly because a widening bandgap fails to increase open-circuit voltage. We report on a bifacial all-perovskite tandem structures with an equivalent efficiency of 29.3% under back-to-front irradiance ratio of 30. This increases energy yield and reduces the required bandgap of a wide-bandgap cell. Open-circuit voltage deficit is therefore minimized, although its performance under only front irradiance is not ideal. The bifacial device needs a sputtered rear transparent electrode, which could reduce photon path length and deteriorate stability of Pb-Sn perovskites. Embedding a light-scattering micrometer-sized particle layer into perovskite to trap light, effectively increases absorptance by 5 to 15% in the infrared region. Using a nonacidic hole transport layer markedly stabilizes the hole-extraction interface by avoiding proton-accelerated formation of iodine. These two strategies together increase efficiency of semitransparent Pb-Sn cells from 15.6 to 19.4%, enabling fabrication of efficient bifacial all-perovskite tandem devices.

A novel U-shaped relationship between mitochondrial mass and risk of incomplete immune reconstitution in HIV-infected patients on antiviral therapy.

Mitochondrial mass (MM) is considered an essential parameter of the immune system, but the association of MM with incomplete immune reconstitution (IIR) in people living with HIV (PLWH) remains unclear. Here, we tested 2148 blood samples from 1999 PLWH by flow cytometry in China between August 2021 and February 2022. A novel U-shaped relationship, determined by multivariable smooth curve fitting and piecewise-linear mixed-effect model, was observed between the ratio of MM to SD (MM/SD) and IIR, with a threshold cutoff of 2.8. For MM/SD <2.8, per SD increment of MM was independently associated with 30%, 30%, 20%, and 20% decreased risk of CD4+ T-cell counts <500 cells/µL after 4 years of treatment and CD4+ T-cell counts <350 cells/µL after 4, 5, 6 years of treatment, respectively. Our study suggested that increasing MM may indicate the low risk of IIR for PLWH with MM/SD <2.8.

Serum CHI3L1 as a Biomarker for Non-invasive Diagnosis of Liver Fibrosis.

BACKGROUND: Liver fibrosis is the early pathological manifestation of various chronic liver diseases (including schistosomiasis, alcoholic, viral, nonalcoholic, fatty liver, etc.), which can progress to cirrhosis and even liver cancer. Out of the 7.7 billion world population, approximately 2 billion individuals have evidence of hepatitis B virus (HBV) infection; of these, 350 to 400 million suffer from chronic HBV infection, accounting for about 5% of the global population. The global prevalence of hepatitis C is 3%. These figures indicate that liver fibrosis is quite common. METHODS: 98 patients with liver fibrosis were included in this study. The serum chitinase-3 Like Protein-1 (CHI3L1) level was measured by the double antibody Sandwich ELISA method. RESULTS: Serum levels of CHI3L1 were significantly different between no-fibrosis and fibrosis groups (P < 0.01). There was a strong correlation between the levels of CHI3L1, elastometry, hyaluronan, CIV (P < 0.01) and age and sex, TBIL, DBIL, ALB, AST, ALT, GGT, ALP, PLT, LN, PIINP, FIB-4, and APRI (P < 0.05). The expression of CHI3L1 was different from fibrosis grades S1, S3, and S4 (P < 0.05, P < 0.001). The expression of CHI3L1 was significantly different between F1 and F4 (P < 0.05). Serum CHI3L1 expression level can be a valuable metric for diagnosing liver fibrosis, with an AUC value of 0.812. Out of the 98 patients who had undergone liver puncture, 79 patients (30.38%) had ALT ≤ 2ULN. CONCLUSIONS: The expression level of serum CHI3L1 was significantly higher in patients with liver fibrosis than that in patients without liver fibrosis. The expression levels of serum CHI3L1 were different in different grades of liver fibrosis and increased with the severity of liver fibrosis. Serum CHI3L1 can distinguish early stage (S1) of liver fibrosis from late stage (S3-4) of liver fibrosis. Serum CHI3L1 combined with HA is even more effective in the diagnosis of S2-4 hepatic fibrosis. The diagnostic efficacy of serum CHI3L1 in patients with ALT ≤ 2ULN was better than that of the other non-invasive diagnostic models.

Determinants and Incidence of Chronic Kidney Disease with Tenofovir- Based Antiretroviral Therapy Regimens: A Cohort Study in HIV-Infected Adults in South China.

BACKGROUND: The data of the impact of tenofovir (TDF) on kidney damage in Chinese HIV-1 infected patients are limited. OBJECTIVE: The study aims to evaluate the incidence and risk factors of stage 3 chronic kidney disease (CKD) and rapid kidney function decline (RKFD) among Chinese HIV-1 infected patients starting with a TDF-based regimen. METHODS: We enrolled 797 TDF-initiated HIV-1-infected patients in a Chinese cohort. Kidney dysfunctions were defined as stage 3 CKD (eGFR < 60 mL/min/1.73 m2 during follow-up) and RKFD (eGFR decline > 10 mL/min/1.73 m2/year). A linear mixed-effects model was used to quantify the average eGFR change per 48 weeks. A generalized estimating equation regression analysis was conducted to determine the risk factors associated with renal dysfunction. The method of multiple imputations was used to reduce the bias caused by missing data. RESULTS: In this retrospective study, 14 (2%) patients experienced stage 3 CKD, and 272 (34%) individuals experienced RKFD during a median of 26 (IQR, 4-78; maximum 325) weeks follow-up period. The mean loss in eGFR per 48 weeks increased consistently over time, from -2.59 mL/min/1.73 m2 before 48 weeks to -17.61 mL/min/1.73 m2 after 288 weeks. For every 10 mL/min/1.73 m2 increase of eGFR, the risk of RKFD increased by 29% (95%CI: 18%, 40%). Each 10 years older and every 10 mL/min/1.73 m2 higher in baseline eGFR, the risk of stage 3 CKD increased to 1.56 (95% CI: 1.00, 2.43) and decreased by 65% (95% CI: 48%, 76%), respectively. Anemia and higher viral load were significantly associated with RKFD. The results were robust across a range of multiple imputation analyses. CONCLUSION: TDF-associated CKD is rare in HIV-1 infected Chinese adults. Longer TDF-exposed patients are more likely to have renal dysfunction, especially those with older age, anemia, lower baseline eGFR, and higher viral load.

Solution-Processed Ternary Tin (II) Alloy as Hole-Transport Layer of Sn-Pb Perovskite Solar Cells for Enhanced Efficiency and Stability.

Tin-lead (Sn-Pb) narrow-bandgap (NBG) perovskites show great potential in both single-junction and all-perovskite tandem solar cells. Sn-Pb perovskite solar cells (PSCs) are still limited by low charge collection efficiency and poor stability. Here, a ternary Sn (II) alloy of SnOCl is reported as the hole-transport material (HTM) with a work function of 4.95 eV for Sn-Pb PSCs. The solution-processed SnOCl layer has a texture structure that not only reduces the optical loss of the devices, but also changes grain growth of Sn-Pb perovskites and boosts the carrier diffusion length to 3.63 µm. The formation of small perovskite grains at the HTM/perovskite interface is suppressed. These result in an almost constant internal quantum efficiency (IQE) of 96 ± 2% across the absorption spectrum of Sn-Pb perovskites. The SnOCl HTM significantly enhances the stability of Sn-Pb PSCs with 87% of its initial efficiency retained after 1-sun illumination for 1200 h, and keeps 85% efficiency under 85 °C thermal stress for 1500 h. The hybrid HTM further improves the stabilized efficiencies of single-junction Sn-Pb PSCs and all-perovskite tandem solar cells to 23.2% and 25.9%, respectively. This discovery opens an avenue to the multicomponent metal alloys as HTM in PSCs.

High grain boundary recombination velocity in polycrystalline metal halide perovskites.

Understanding carrier recombination processes in metal halide perovskites is fundamentally important to further improving the efficiency of perovskite solar cells, yet the accurate recombination velocity at grain boundaries (GBs) has not been determined. Here, we report the determination of carrier recombination velocities at GBs (SGB) of polycrystalline perovskites by mapping the transient photoluminescence pattern change induced by the nonradiative recombination of carriers at GBs. Charge recombination at GBs is revealed to be even stronger than at surfaces of unpassivated films, with average SGB reaching 2200 to 3300 cm/s. Regular surface treatments do not passivate GBs because of the absence of contact at GBs. We find a surface treatment using tributyl(methyl)phosphonium dimethyl phosphate that can penetrate into GBs by partially dissolving GBs and converting it into one-dimensional perovskites. It reduces the average SGB by four times, with the lowest SGB of 410 cm/s, which is comparable to surface recombination velocities after passivation.

Influence of voids on the thermal and light stability of perovskite solar cells.

The formation of voids in perovskite films close to the buried interface has been reported during film deposition. These voids are thought to limits the efficiency and stability of perovskite solar cells (PSCs). Here, we studied the voids formed during operation in perovskite films that were optimized during the solution deposition process to avoid voids. New voids formed during operation are found to assemble along grain boundaries at the bottom interface, caused by the loss of residual solvent and conversion of amorphous phase to crystalline phase. Unexpectedly, the formation of these voids did not negatively affect the stability of PSCs. Decreasing the amorphous region in perovskites by thermal annealing decreased the positive iodide interstitial density, and improved the light stability of PSCs. The annealed devices maintained 90% of their initial efficiency and light soaking for 1900 hours at open circuit condition under 1-sun illumination at 50°C.

Sensitive Imaging of Cellular RNA via Cascaded Proximity-Induced Fluorogenic Reactions.

Owing to its important biological functions, RNA has become a promising molecular biomarker of various diseases. With a dynamic change in its expression level and a relatively low amount within the complicated biological matrix, signal amplification detection based on DNA probes has been put forward, which is helpful for early diagnosis and prognostic prediction. However, conventional methods are confined to cell lysates or dead cells and are not only time-consuming in sample preparation but also inaccessible to the spatial-temporal information of target RNAs. To achieve live-cell imaging of specific RNAs, both the detection sensitivity and intracellular delivery issues should be addressed. Herein, a new cascaded fluorogenic system based on the combination of hybridization chain reactions (HCRs) and proximity-induced bioorthogonal chemistry is developed, in which a bioorthogonal reaction pair (a tetrazine-quenched dye and its complementary dienophile) is brought into spatial proximity upon target RNA triggering the HCR to turn on and amplify the fluorescence in one step, sensitively indicating the cellular distribution of RNA with minimal false positive results caused by unspecific degradation. Facilitated by a biodegradable carrier based on black phosphorus with high loading capacity and excellent biocompatibility, the resulting imaging platform allows wash-free tracking of target RNAs inside living cells.

Mild Behavioral Impairment: An Early Sign and Predictor of Alzheimer's Disease Dementia.

BACKGROUND: Alzheimer's disease (AD) is the most common form of dementia in the elderly population and places heavy burdens on medical care and nursing. Recently, the psychiatric and behavioral symptoms of prodromal AD, especially mild behavioral impairment (MBI), have attracted much attention. In 2012, Alzheimer's Association International Conference, MBI was proposed as a syndrome with psychiatric and behavioral disturbance before the onset of typical clinical cognitive symptoms in dementia. Increasing lines of evidence have indicated the link between MBI and early AD pathologies including Aß and tau. OBJECTIVE: This narrative review aims to summarize the advantages of MBI over other concept of psychiatric and behavioral symptoms associated with AD in the early prediction of AD dementia. We also discuss the possible common genetic basis and pathological mechanisms underlying the interactions between MBI and AD. METHODS: Papers cited here were retrieved from PubMed up to February 2022. We selected a total of 95 articles for summary and discussion. RESULTS: The occurrence of MBI is mainly due to the overlapped genetic and pathological risk factors with AD and is related to the brain's response to environmental stressors. MBI may be a warning sign for the early pathology of AD, and more attention should be paid on the number and duration of MBI symptoms. CONCLUSION: MBI may be an early sign and predictor of Alzheimer's disease dementia. Early intervention for MBI may have a positive effect on alleviating long-term cognitive decline.

Integrated Ideal-Bandgap Perovskite/Bulk-Heterojunction Solar Cells with Efficiencies > 24.

Here, the authors report a highly efficient integrated ideal-bandgap perovskite/bulk-heterojunction solar cell (IPBSC) with an inverted architecture, featuring a near infrared (NIR) polymer DTBTI-based bulk-heterojunction (BHJ) layer atop guanidinium bromide (GABr)-modified FA0.7 MA0.3 Pb0.7 Sn0.3 I3 perovskite film as the photoactive layer. The IPBSC shows cascade-like energy level alignment between the charge-extractionlayer/perovskite/BHJ and efficient passivation effect of BHJ on perovskite. Thanks to the well-matched energy level alignment and high-quality ideal bandgap-based perovskite film, an efficient charge transfer occurs between the charge-extraction-layer/perovskite/BHJ. Moreover, the NIR polymer DTBTI on the perovskite film leads to an improved NIR light response for the IPBSC. In addition, the O, S and N atoms in the DTBTI polymer yield a strong interaction with perovskite, which is conducive to reducing the defects of the perovskite and suppressing charge recombination. As a result, the solar cell achieves a power conversion efficiency (PCE) of 24.27% (certificated value at 23.4% with 0.283-volt voltage loss), currently the recorded efficiency for both IPBSCs and Pb-Sn alloyed PSCs, and which is over the highest efficiency of perovskite-organic tandem solar cell. Moreover, the thermal, humidity and long-term operational stabilities of the IPBSCs are also significantly improved compared with the control PSCs.

Controllable Heterogenous Seeding-Induced Crystallization for High-Efficiency FAPbI3 -Based Perovskite Solar Cells Over 24.

The addition of small seeding particles into a supersaturated solution is one among the most effective approaches to obtain high-quality semiconductor materials via increased crystallization rates. However, limited study is conducted on this approach for the fabrication of perovskite solar cells. Here, a new strategy-"heterogenous seeding-induced crystallization (hetero-SiC)" to assist the growth of FAPbI3 -based perovskite is proposed. In this work, di-tert-butyl(methyl)phosphonium tetrafluoroborate is directly introduced into the precursor, which forms a low-solubility complex with PbI2 . The low-solubility complex can serve as the seed to induce crystallization of the perovskite during the solvent-evaporation process. Various in situ measurement tools are used to visualize the hetero-SiC process, which is shown to be an effective way of manipulating the nucleation and crystal growth of perovskites. The hetero-SiC process greatly improves the film quality, reduces film defects, and suppresses nonradiative recombination. A hetero-SIC proof-of-concept device exhibits outstanding performance with 24.0% power conversion efficiency (PCE), well over the control device with 22.2% PCE. Additionally, hetero-SiC perovskite solar cell (PSC) stability under light illumination is enhanced and the PSC retains 84% of its initial performance after 1400 h of light illumination.

Machine learning to predict post-operative acute kidney injury stage 3 after heart transplantation.

BACKGROUND: Acute kidney injury (AKI) stage 3, one of the most severe complications in patients with heart transplantation (HT), is associated with substantial morbidity and mortality. We aimed to develop a machine learning (ML) model to predict post-transplant AKI stage 3 based on preoperative and perioperative features. METHODS: Data from 107 consecutive HT recipients in the provincial center between 2018 and 2020 were included for analysis. Logistic regression with L2 regularization was used for the ML model building. The predictive performance of the ML model was assessed using the area under the curve (AUC) in tenfold stratified cross-validation and was compared with that of the Cleveland-clinical model. RESULTS: Post-transplant AKI occurred in 76 (71.0%) patients including 15 (14.0%) stage 1, 18 (16.8%) stage 2, and 43 (40.2%) stage 3 cases. The top six features selected for the ML model to predicate AKI stage 3 were serum cystatin C, estimated glomerular filtration rate (eGFR), right atrial long-axis dimension, left atrial anteroposterior dimension, serum creatinine (SCr) and FVII. The predictive performance of the ML model (AUC: 0.821; 95% confidence interval [CI]: 0.740-0.901) was significantly higher compared with that of the Cleveland-clinical model (AUC: 0.654; 95% [CI]: 0.545-0.763, p < 0.05). CONCLUSIONS: The ML model, which achieved an effective predictive performance for post-transplant AKI stage 3, may be helpful for timely intervention to improve the patient's prognosis.

Blading of Conformal Electron-Transport Layers in p-i-n Perovskite Solar Cells.

Perovskite solar cells (PSCs) are promising to reduce the cost of photovoltaic system due to their low-cost raw materials and high-throughput solution process; however, fabrication of all the active layers in perovskite modules using a scalable solution process has not yet been demonstrated. Herein, the fabrication of highly efficient PSCs and modules in ambient conditions is reported, with all layers bladed except the metal electrode, by blading a 36 ± 9 nm-thick electron-transport layer (ETL) on perovskite films with a roughness of ≈80 nm. A combination of additives in phenyl-C61 -butyric acid methyl ester (PCBM) allows the PCBM to conformally cover the perovskites and still have a good electrical conductivity. Amine-functionalized molecules are added to enhance both the dispersity of PCBM and the affinity to perovskites. A PCBM dopant of 4-(2,3-dihydro-1,3-dimethyl-1H-benzimidazol-2-yl)-N,N-dimethylbenzenamine (N-DMBI) recovers the conductivity loss induced by the small amine molecules. PSCs (0.08 cm2 ) fabricated by the all-blading process reache an average efficiency of 22.4 ± 0.5% and a champion efficiency of 23.1% for perovskites with a bandgap of 1.51 eV, with much better stability compared to evaporated ETL PSCs. The all-bladed minimodule (25.03 cm2 ) shows an aperture efficiency of ≈19.3%, showing the good uniformity of the bladed ETLs.

Risk factors of renal replacement therapy after heart transplantation: a retrospective single-center study.

Background: Acute kidney injury (AKI) and renal replacement therapy (RRT) are common after heart transplantation (HT). The need for RRT has been reported to be one of the most important predictors of a poor prognosis after HT. Therefore, it is important to early identify risk factors of RRT after HT. However, in the heart transplantation setting, the risk factors are less well studied, and some of the conclusions are controversial. This study aimed to identify the clinical predictors of RRT after HT. Methods: This single-center, retrospective study from January 2010 to June 2021 analyzed risk factors (pre-, intra-, and postoperative characteristics) of 163 patients who underwent HT. The endpoint of the study was RRT within 7 days of HT. Risk factors were analyzed by multivariable logistic regression models. Results: Fifty-five (33.74%) recipients required RRT within 7 days of HT. Factors independently associated with RRT after HT were as follows: a baseline estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m2 [odds ratio (OR) =3.123; 95% confidence interval (CI): 1.183-8.244; P=0.022], a dose of intraoperative methylprednisolone >10 mg/kg (OR =3.197; 95% CI: 1.290-7.923; P=0.012), the use of mechanical circulatory support (MCS) during surgery (OR =4.903; 95% CI: 1.628-14.766; P=0.005), a cardiopulmonary bypass (CPB) time ≥5 hours (OR =3.929; 95% CI: 1.222-12.634; P=0.022), and postoperative serum total bilirubin (TBIL) ≥60 umol/L (OR =5.105; 95% CI: 1.868-13.952; P=0.001). Protective factors were higher postoperative serum albumin (OR =0.907; 95% CI: 0.837-0.983; P=0.017) and higher postoperative left ventricular ejection fraction (LVEF) (OR =0.908; 95% CI: 0.838-0.985; P=0.020). Conclusions: A low preoperative eGFR, a high intraoperative dose of methylprednisolone, a long CPB time, the use of mechanical circulatory support, and a high postoperative TBIL were risk factors for RRT after HT. While a high postoperative serum albumin level and a high left ventricular ejection fraction were protective factors. Understanding these risk factors may help us identify high-risk patients and intervene early.

Sustainable production and characterization of medium-molecular weight welan gum produced by a Sphingomonas sp. RW.

Welan gum is widely used in food, concrete, and oil recovery for its excellent stability and unique rheological properties. This study describes an engineered Sphingomonas sp. RW strain deficient in the lyase gene (welR) and outlines its application in an industrial by-product fermentation strategy to produce welan gum. The yield of the engineered strain was enhanced to 25.11 ± 0.05 g/L, whereas the broth viscosity (2110 mPas) increased by 281.81%. The welan gum produced by Sphingomonas sp. RW was named medium-molecular weight welan gum (MMWG, ~350 kDa). FT-IR and monosaccharide composition analysis revealed that the MMWG was composed of l-mannose, l-rhamnose, glucuronic acid, and glucose (with mole ratios of 1:4.46:1.26:2.82). Significantly, MMWG had favorable hydroxyl radical scavenging activity and emulsifying capacity. These results provide a strategy for cost-effective welan gum production and enrich the properties of welan gum with different molecular weight.