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1.
BMC Cancer ; 21(1): 20, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33402102

RESUMO

BACKGROUND: Curing locally advanced gastric cancer through surgery alone is difficult. Adjuvant and neoadjuvant chemotherapy bring potential benefits to more patients with gastric cancer based on several clinical trials. According to phase II studies and guidelines, SOX regimen as neoadjuvant chemotherapy is efficient. However, the optimal duration of neoadjuvant chemotherapy has not been established. In this study, we will evaluate the efficacy and safety of different cycles of SOX as neoadjuvant chemotherapy for patients with locally advanced gastric cancer. METHODS: RESONANCE-II trial is a prospective, multicenter, randomized, controlled phase III study which will enroll 524 patients in total. Eligible patients will be registered, pre-enrolled and receive three cycles of SOX, after which tumor response evaluations will be carried out. Those who show stable disease or progressive disease will be excluded. Patients showing complete response or partial response will be enrolled and assigned into either group A for another three cycles of SOX (six cycles in total) followed by D2 surgery; or group B for D2 surgery (three cycles in total). The primary endpoint is the rate of pathological complete response and the secondary endpoints are R0 resection rate, three-year disease-free survival, five-year overall survival, and safety. DISCUSSION: This study is the first phase III randomized trial to compare the cycles of neoadjuvant chemotherapy using SOX for resectable locally advanced cancer. Based on a total of six to eight cycles of perioperative chemotherapy usually applied in locally advanced gastric cancer, patients in group A can be considered to have completed all perioperative chemotherapy, the results of which may suggest the feasibility of using chemotherapy only before surgery in gastric cancer. TRIAL REGISTRATION: Registered prospectively in the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) with registration number ChiCTR1900023293 on May 21st, 2019.

2.
BMC Geriatr ; 21(1): 14, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407187

RESUMO

BACKGROUND: With the extended life expectancy of the Chinese population and improvements in surgery and anesthesia techniques, the number of aged patients undergoing surgery has been increasing annually. However, safety, effectiveness, and quality of life of aged patients undergoing surgery are facing major challenges. In order to standardize the perioperative assessment and procedures, we have developed a perioperative evaluation and auxiliary decision-making system named "Aged Patient Perioperative Longitudinal Evaluation-Multidisciplinary Trial (APPLE-MDT)". METHODS: We will conduct a perioperative risk evaluation and targeted intervention, with follow-ups at 1, 3, and 6 months after surgery. The primary objective of the study is to evaluate the effectiveness of the "Aged Patient Perioperative Longitudinal Evaluation-Multiple Disciplinary Trial Path" (hereinafter referred to as the APPLE-MDT path) in surgical decision-making for aged patients (≥75 years) undergoing elective surgery under non-local anesthesia in the operating room. The secondary objectives of the study are to evaluate the postoperative outcome and health economics of the APPLE-MDT path applied to the surgical decision-making of aged patients (≥75 years) undergoing elective surgery under non-local anesthesia and to optimize intervention strategies for aged patients undergoing surgery to reduce the occurrence of postoperative complications and improve the quality of life after surgery. DISCUSSION: It is necessary to formulate a reliable, effective, and concise evaluation tool, which can effectively predict the perioperative complications and mortality of aged patients, support targeted intervention strategies, and allow for a more comprehensive risk and benefit analysis, thereby forming an effective senile perioperative surgery management path. It is expected that the implementation of this protocol can reduce the occurrence of postoperative complications, improve the postoperative quality of life, shorten hospital stay, reduce hospitalization expenses, reduce social burden, and allow the elderly to have a good quality of life after surgery. TRIAL REGISTRATION: ChiCTR, ChiCTR1800020363 , Registered 15 December 2018.

3.
Exp Appl Acarol ; 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33484388

RESUMO

The structures of arthropod bacterial communities are complex. These microbiotas usually provide many beneficial services to their hosts, whereas occasionally they may be parasitical. To date, little is known about the bacterial communities of Tetranychus truncatus and the factors contributing to the structure of its bacterial communities are unexplored yet. Here, we used four symbiont-infected T. truncatus strains-including one Wolbachia and Spiroplasma co-infected strain, two symbiont singly-infected strains and one symbiont uninfected strain-to investigate the influence of endosymbionts on the structure of the host mites' microbiota. Based on 16S rRNA genes sequencing analysis, we found Wolbachia and Spiroplasma were the two most abundant bacteria in T. truncatus and the presence of both symbionts could not change the diversity of bacterial communities (based on alpha-diversity indexes such as ACE, Chao1, Shannon and Simpson diversity index). Symbiont infection did alter the abundance of many other bacterial genera, such as Megamonas and Bacteroides. The structures of bacterial communities differed significantly among symbiont-infected strains. These results suggested a prominent effect of Wolbachia and Spiroplasma on bacterial communities of the host T. truncatus. These findings advance our understanding of T. truncatus microbiota and will be helpful for further study on bacterial communities of spider mites.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33462695

RESUMO

With the deepening implementation of the energy revolution and the advent of the era in which renewable energy will be grid parity, China's offshore wind power projects have gradually taking steps to shape a large-scale development. This paper reviews the relevant policies for offshore wind power, adopting the levelized cost of electricity (LCOE) model to conduct an economic evaluation of offshore wind power projects in six typical provinces in China. Among the six provinces studied in this paper, Hebei Province has the highest LCOE value of 0.87 yuan/kWh, and Fujian Province has the lowest LCOE value of 0.71 yuan/kWh; the LCOE results of offshore wind power projects in Hebei and Guangdong provinces are higher than the policy guidance price by 8.75% and 6.25% respectively; the LCOE value of the offshore wind power projects in the other four provinces are lower than the guidance price, and the average profit is considerable; the expected annual utilization hours and unit cost have varied impact on the LCOE value in different provinces. The results show that with the upcoming offshore wind power on-grid price bidding era, China's offshore wind power grid parity era is just around the corner. Finally, this paper puts forward relevant policy suggestions, hoping to provide practical guidance for the promotion of offshore wind power technology in China.

5.
Clin Appl Thromb Hemost ; 27: 1076029620986862, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33426903

RESUMO

The purpose of this study was to identify patients at higher risk of deep venous thrombosis (DVT) in the uninjured lower extremity both preoperatively and postoperatively in patients with lower extremity fractures. We collected the clinical data of patients with lower extremities fractures who presented at Xi'an Honghui Hospital between 1 July, 2015 and 31 October, 2017. Doppler ultrasonography was used to diagnose the DVT. Patients were examined pre- and postoperatively. The patients were divided into thrombosis group and no thrombosis group according to the preoperative and postoperative ultrasonography results. The thrombosis group was defined as patients with DVT in the uninjured lower extremity and the no thrombosis group was defined as patients without DVT in the uninjured lower extremity. This study enrolled 1454 patients who met the inclusion criteria. The incidence of preoperative DVT in the uninjured lower extremity was 9.63% whereas the postoperative incidence was 20.29%. Age (OR = 0.965, 95 CI%: 0.954-0.977; P ≤ 0.001) and female (OR = 0.667, 95% CI: 0.451-0.986, P = 0.042) were independent risk factors for preoperative DVT in the uninjured lower extremity. Blood loss (OR = 0.997, 95 CI%: 0.995-1.000; P = 0.020), D-dimer level at admission (OR = 0.941, 95 CI%: 0.887-0.999; P = 0.045), and postoperative day 5 D-dimer level (OR = 0.889, 95 CI%: 0.819-0.965; P = 0.005), were independent risk factors for postoperative DVT in the uninjured lower extremity. For the patients with lower extremity fractures, age and female were associated with the preoperative DVT in the uninjured lower extremity. Blood loss, D-dimer at admission and postoperative day 5 D-dimer were associated with the postoperative DVT in the uninjured lower extremity.

6.
Acta Diabetol ; 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452595

RESUMO

AIMS: To investigate the association between fibroblast growth factor 21 (FGF21) levels and glycemic response to exenatide in patients with type 2 diabetes. METHODS: The exploratory analysis of a multi-center trial included 190 patients with type 2 diabetes inadequately controlled by monotherapy or combination therapy of metformin and insulin secretagogues. All participants received exenatide twice daily as an add-on therapy for 16 weeks. Serum FGF21 and other information at the baseline and end of follow-ups were obtained. Linear regression analysis was used to determine the correlations between baseline FGF21 levels and HbA1c reduction from baseline after the treatment. RESULTS: After 16 weeks of treatment with exenatide, a decline in the HbA1c levels from baseline was associated with higher baseline FGF21 levels among all participants (r = 0.193, P = 0.008) and in subgroup of the participants receiving background metformin monotherapy (r = 0.231, P = 0.034). Compared with patients in the lowest FGF21 quartile, patients in the highest FGF21 quartile showed a significantly weakened decline in HbA1c levels from baseline among all participants (ß = - 0.16 [95% Cl - 0.31 to - 0.01], P < 0.05) and in subgroup of the participants receiving background metformin monotherapy (ß = - 0.23 [95% Cl - 0.43 to - 0.03], P < 0.05), after adjusting for the confounding factors, including age, sex, and baseline HbA1c levels. CONCLUSIONS: The high baseline FGF21 levels are associated with poor glycemic responses to exenatide in patients with type 2 diabetes. Therefore, FGF21 could be used as a biomarker for predicting the efficacy of exenatide treatment. TRIAL REGISTRATION: ChiCTR-IPR-15006558, date registered May 27, 2015.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33409585

RESUMO

BACKGROUND: The role of intraoperative use of indocyanine green (ICG) fluorescence angiography (ICGFA) to prevent anastomotic leakage (AL) in rectal cancer surgery remains controversial. METHODS: The systematic review for studies evaluating ICGFA in patients undergoing rectal cancer surgery in PubMed, Embase, Web of Science, and the Cochrane Library was performed up to April 30, 2020. The primary outcome was the incidence of AL. The analysis was performed using RevMan v5.3 and Stata v12.0 software. RESULTS: Eighteen studies comprising 4038 patients were included. In the present meta-analysis, intraoperative use of ICGFA markedly reduced AL rate (OR = 0.33; 95% CI: 0.24-0.45; P < 0.0001; I2 = 0%) in rectal cancer surgery, which was still significant in surgeries limited to symptomatic AL (OR = 0.44; 95% CI: 0.31-0.64; P < 0.0001; I2 = 22%). This intervention was also associated with shorter postoperative stays (MD = - 1.27; 95% CI: - 2.42 to - 0.13; P = 0.04; I2 = 60%). However, reoperation rate (OR = 0.61; 95% CI: 0.34-1.10; P = 0.10; I2 = 6%), ileus rate (OR = 1.30; 95% CI: 0.60-2.82; P = 0.51; I2 = 56%), and surgical site infection rate (OR = 1.40; 95% CI: 0.62-3.20; P = 0.42; I2 = 0%) were not significantly different between the two groups. CONCLUSION: The use of ICGFA was associated with a lower AL rate after rectal cancer resection. However, more multi-center RCTs with large sample size are required to further verify the value of ICGFA in rectal cancer surgery.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33409962

RESUMO

Left atrial sphericity index (LASI) is one significant geometric remodeling parameter to evaluate the prognosis of atrial fibrillation (AF). We aimed to determine whether transthoracic echocardiography (TTE)-derived LASI may help predict the outcomes following AF radiofrequency catheter ablation (RFCA). This prospective study enrolled 190 consecutive AF patients who underwent TTE 24 h before RFCA. LASI was calculated as the ratio of left atrial maximum volume to spherical volume. After 1-year follow-up, 56 patients (29.5%) relapsed. Multivariate Cox regression showed that LASI (hazard ratio = 1.48, 95% Cl 1.15-1.92, P = 0.003) was an independent predictor of AF recurrence. Stratifying patients into four subgroups with different LAVI showed that high LASI value indicated a high risk of recurrence, especially in patients with mildly and moderately enlarged atria (the recurrence rate was 0% vs. 26.3%, P = 0.049; 9.5% vs. 40.9%, P = 0.018, respectively). In conclusion, TTE-derived LASI may be useful to predict AF recurrence after RFCA.

9.
Environ Sci Technol ; 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33412847

RESUMO

Biomass chars are a major component of the soil environmental black carbon pool and prepared forms are a potentially useful tool in remediation. A function critical to the roles of both environmental and prepared chars is sorption of organic compounds. Char properties known to control sorption include surface area, porosity, functional group composition, and percent aromatic carbon. Here, we show that sorption affinity (but not maximum capacity) of organic compounds is directly related to the degree of condensation of the aromatic fraction. The Dubinin-Ashtakov characteristic sorption energy (EDA, kJ mol-1) of 22 compounds on a thermoseries of bamboo chars correlates strongly with the DP/MAS-13C NMR-determined bridgehead aromatic carbon fraction (χb), which relates to the mean ring cluster size. Density functional theory-computed binding energy (Ebd) for five of the compounds on a representative series of polybenzenoid hydrocarbon open-face sheets also correlates positively with χb, leveling off for rings larger than ∼C55. The Ebd, in turn, correlates strongly with EDA. An increase in Ebd with cluster size is also found for sorption, both monolayer and bilayer, between parallel sheets representing slit micropores. The increasing sorption energy with cluster size is shown to be due to increasing cluster polarizability, which strengthens dispersion forces with the sorbate. The findings underscore a previously overlooked explicit role of aromatic condensation in sorption energy, and illustrate the utility of EDA-Ebd comparison for predicting sorption.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33394411

RESUMO

Lake surface water temperature (LSWT) is an important factor affecting a lake's ecological environment. In recent decades, LSWT worldwide has shown an increasing trend in the context of global climate change. This rising trend has been more evident in urban lakes. With the rapid development of urbanization, urban lakes are affected not only by climate warming but also by human activities. Among these factors, due to the increase in impervious surface coverage (ISC), the impact of thermal runoff pollution caused by precipitation events on urban lakes cannot be ignored. Therefore, this study used the Dianchi Lake watershed as a study area, and the surface water temperature of Dianchi Lake, the precipitation data, and the land use data were collected and analyzed. Based on these data, the influence of precipitation events on the surface water temperature of Dianchi Lake was analyzed. The research results show that under the background of different ISC levels and different growth rates of impervious surface area (ISA), precipitation events have different effects on the LSWT. When ISC is low and the growth rate of ISA is slow, the annual precipitation is negatively correlated with the annual average surface water temperature of Dianchi Lake (r = - 0.183). When ISC is high and the growth rate of ISA is fast, the annual precipitation is positively correlated with the average annual surface water temperature of Dianchi Lake (r = 0.65). With the increase in ISC, the correlation between seasonal precipitation and the average surface water temperature in Dianchi Lake changed from negative to positive in spring and autumn. Under the action of impervious surfaces, precipitation events have a warming effect on the surface water temperature of the lake, and this effect will be intensified with the increase in ISC.

11.
Nano Lett ; 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33401909

RESUMO

Hydrogel materials with high water content and good biocompatibility are drawing more and more attention now, especially for biomedical use. However, it still remains a challenge to construct hydrogel fibers with enough strength and toughness for practical applications. Herein, we report a bio-inspired lotus-fiber-mimetic spiral structure hydrogel bacterial cellulose fiber with high strength, high toughness, high stretchability, and energy dissipation, named biomimetic hydrogel fiber (BHF). The spiral-like structure endows BHF with excellent stretchability through plastic deformation and local failure, assisted by the breaking-reforming nature of the hydrogen bonding network among cellulose nanofibers. With the high strength, high stretchability, high energy dissipation, high hydrophilicity, porous structure, and excellent biocompatibility, BHF is a promising hydrogel fiber for biomedicine. The outstanding stretchability and energy dissipation of BHF allow it to absorb energy from the tissue deformation around a wound and effectively protect the wound from rupture, which makes BHF an ideal surgical suture.

12.
Org Lett ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33439028

RESUMO

Three emissive bridged-triphenylamine derivatives are designed and synthesized by incorporating carbon (DQAO), oxygen (OQAO), and sulfur (SQAO) atoms with two carbonyl groups. The fully bridged geometry and unique frontier molecular orbital distribution reveal its potential as narrowband thermally activated delayed fluorescence emitters. DQAO-, OQAO-, and SQAO-based organic light-emitting diodes exhibit the maximum external quantum efficiency (EQEmax) of 15.2%, 20.3%, and 17.8% for blue, green, and yellow, respectively.

13.
Free Radic Biol Med ; 163: 220-233, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33359683

RESUMO

Nonalcoholic steatohepatitis (NASH) is an increasingly prevalent liver disease linked to obesity and associated complications. Endoplasmic reticulum (ER) stress provokes dysfunction in lipid metabolism, which often leads to a progression of obesity-induced hepatic steatosis to NASH. However, the underlying mechanisms in which ER stress in adipose tissue induces hepatic pathology remain elusive. Here, we used male C57BL/6J mice to develop an animal model of NASH induced by a high fat (HFD) diet and methionine- and choline-deficient (MCD) diets. Using a gene-silencing approach with a recombinant lentiviral vector and extensive LC-MS/MS-based proteomics and lipidomics, we demonstrate that the ER stress-induced adipocyte-secreted exosome (ATEx) orchestrates lipid dynamics in the liver. We also noted that ATEx causes hepatic steatosis, inflammation, and fibrosis that lead to NASH through initial accumulation of glycerol and triglycerides in hepatocytes. We also determined that aldo-keto-reductase 1B7 (Akr1b7), a key mediator in liver lipid metabolism, is involved in ATEx-mediated NASH induction. Of note, Akr1b7 deficiency in ER stress-induced ATEx strongly protected the murine liver against HFD and MCD-induced NASH. Our results indicated that ER stress-induced, adipocyte-secreted ATEx triggers NASH by delivering exosomal AKR1B7 to, and elevating glycerol level, in hepatocytes. These findings suggest potential therapeutic strategie that target ATEx to prevent or manage obesity-induced NASH.

14.
Neuroreport ; 32(2): 77-81, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33323835

RESUMO

Isoflurane is an inhaled anesthetic, though its actions at the cellular level remain controversial. By using acute spinal cord slices from adult rats and the whole-cell recording technique, we found that aqueous isoflurane at the minimum alveolar concentration decreased postsynaptic neural excitability and enhanced membrane conductance, while suppressing glutamate release from presynaptic afferent onto substantia gelatinosa (lamina II) neurons in the dorsal horn. The data demonstrate that isoflurane modulates synaptic transmission from peripheral to the spinal cord via both pre- and postsynaptic effects and these actions may underlie its spinal anesthesia.

15.
J Alzheimers Dis ; 79(2): 653-661, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33337379

RESUMO

BACKGROUND: Education plays a potential important effect on the prevalence and incidence of dementia. However, most of the evidence based on convenience sampling. OBJECTIVE: To explore effects of education on cognition in individuals with subjective cognitive decline (SCD) and cognitive impairment (CI) from a population-based study. METHODS: We examined the effect of education on cognition among individuals with SCD (n = 451) and CI (n = 280) from a population-based study. A series of neuropsychological tests of memory, executive, language, and general cognitive function were used to assess the participants. RESULTS: Multiple regression analyses revealed that education has a positive effect on cognition in both SCD and CI group in the population-based research. Further stratification study showed that the beneficial effect of education remains in the SCD group regardless of the education level, especially in the SCD participants with a low education level. However, that effect of education exists in the CI group with a low education level and disappears in the high education level. CONCLUSION: These results from a population-based sample suggest that high educational attainment may delay cognitive decline in the individuals with SCD regardless of high or low educational level, and high education only predicts cognition in those in the low educational level in CI group.

16.
Entropy (Basel) ; 22(11)2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33286982

RESUMO

The heat transfer and entropy generation in a tube filled with double-layer porous media are analytically investigated. The wall of the tube is subjected to a constant heat flux. The Darcy-Brinkman model is utilized to describe the fluid flow, and the local thermal non-equilibrium model is employed to establish the energy equations. The solutions of the temperature and velocity distributions are analytically derived and validated in limiting case. The analytical solutions of the local and total entropy generation, as well as the Nusselt number, are further derived to analyze the performance of heat transfer and irreversibility of the tube. The influences of the Darcy number, the Biot number, the dimensionless interfacial radius, and the thermal conductivity ratio, on flow and heat transfer are discussed. The results indicate, for the first time, that the Nusselt number for the tube filled with double-layer porous media can be larger than that for the tube filled with single layer porous medium, while the total entropy generation rate for the tube filled with double-layer porous media can be less than that for the tube filled with single layer porous medium. And the dimensionless interfacial radius corresponding to the maximum value of the Nusselt number is different from that corresponding to the minimum value of the total entropy generation rate.

17.
Bioorg Med Chem Lett ; 33: 127750, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33340662

RESUMO

Targeting specific mitochondrial alterations to kill cancer cells without affecting their normal counterparts emerges as a feasible strategy. Coumarin derivatives have demonstrated the potential anti-breast cancer activities. By coupling coumarin-3-carboxamide derivatives with mitochondria carrier triphenylphosphonium, mitocoumarins 15a-c were produced and tested as the anti-breast cancer fluorescence agents. Among them, 15b as the amide-based drug potently suppressed the cell growth in MCF-7, MDA-231, SK-BR-3 breast cancer cells with the IC50 values from 3.0 to 4.1 µM, including the lower cytotoxicity to normal MCF-10A cells with the IC50 value around 45.30 ± 2.45 µM. In mechanistic study for 15b in MDA-MB-231 cells, it could localize in mitochondria to elicit ROS burst and collapse Δψm. Besides, it could deplete GSH by an irreversible alkylation process and moderately inhibit mitochondrial thioredoxin reductase TrxR2, thus leading to aggravate cellular oxidative stress. This study reported 15b might be useful for the further development into a mitochondria-targeted anti-triple negative breast cancer drug.

18.
Sensors (Basel) ; 20(23)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33255800

RESUMO

Currently, intelligent security systems are widely deployed in indoor buildings to ensure the safety of people in shopping malls, banks, train stations, and other indoor buildings. Multi-Object Tracking (MOT), as an important component of intelligent security systems, has received much attention from many researchers in recent years. However, existing multi-objective tracking algorithms still suffer from trajectory drift and interruption problems in crowded scenes, which cannot provide valuable data for managers. In order to solve the above problems, this paper proposes a Multi-Object Tracking algorithm for RGB-D images based on Asymmetric Dual Siamese networks (ADSiamMOT-RGBD). This algorithm combines appearance information from RGB images and target contour information from depth images. Furthermore, the attention module is applied to repress the redundant information in the combined features to overcome the trajectory drift problem. We also propose a trajectory analysis module, which analyzes whether the head movement trajectory is correct in combination with time-context information. It reduces the number of human error trajectories. The experimental results show that the proposed method in this paper has better tracking quality on the MICC, EPFL, and UMdatasets than the previous work.

19.
Gut Microbes ; 12(1): 1-18, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33289609

RESUMO

Gut microbial communities of athletes differ from that of sedentary persons in both diversity and the presence of certain taxa. However, it is unclear to what degree elite athletes and non-elite athletes harbor different gut microbial community patterns and if we can effectively monitor the potential of athletes based on microbiota. A team of professional female rowing athletes in China was recruited and 306 fecal samples were collected from 19 individuals, which were separated into three cohorts: adult elite athlete's (AE), youth elite athlete's (YE), and youth non-elite athlete's (YN). The differences in gut microbiome among different cohorts were compared, and their associations with dietary factors, physical characteristics, and athletic performance were investigated. The microbial diversities of elite athletes were higher than those of youth non-elite athletes. The taxonomical, functional, and phenotypic compositions of AE, YE and YN were significantly different. Additionally, three enterotypes with clear separation were identified in athlete's fecal samples, with majority of elite athletes stratified into enterotype 3. And this enterotype-dependent gut microbiome is strongly associated with athlete performances. These differences in athlete gut microbiota lead to establishment of a random forest classifier based on taxonomical and functional biomarkers, capable of differentiating elite athletes and non-elite athletes with high accuracy. Finally, these versatilities of athlete microbial communities of athletes were found to be associated with dietary factors and physical characteristics, which can in concert explain 41% of the variability in gut microbiome.

20.
Sci Total Environ ; : 143866, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33293096

RESUMO

Fe/C composite is emerging as a promising nanoscale zero-valent iron (nZVI) based material for wastewater treatment to counteract the limitations of nZVI, while its preparation method, structure-activity relationship, and working mechanisms and conditions still need to be studied. In this study, Fe/C composites derived from iron-crosslinked alginate was successfully achieved via high temperature pyrolysis. Ferric ions were only transformed into Fe3O4/γ-Fe2O3 at low pyrolysis temperature (≤500 °C), whereas Fe0/Fe3C became the primary Fe species with the formation of graphitic carbon at elevated pyrolysis temperature (≥700 °C). Fe/C composites from higher pyrolysis temperature presented better performance in atrazine (ATZ) removal, and the optimal pyrolysis temperature was 800 °C (Fe/C-800). Batch experiments showed that the removal kinetics of ATZ (10 mg L-1) by Fe/C-800 (0.2 g L-1) followed pseudo-second-order model, and 24-h ATZ removal efficiency maintained at 93.5 ± 1.0% within pH 3-9. The adsorption by the graphitic carbon phase of Fe/C-800 was the principal contributor to the pH-independent superior performance in ATZ removal, and the Langmuir model fitted adsorption capacity was 64.8 mg g-1 at pH 6. Although the carbon-phase adsorbed ATZ was basically unavailable for degradation, Fe0/Fe3C-mediated ATZ degradation contributed to the great reactivity of Fe/C-800 at pH 3. Fe0/Fe3C in Fe/C-800 was more efficient for ATZ degradation than commercial nZVI, and oxidative dealkylation by Fe0/Fe3C mediated Fenton reaction was the predominant ATZ degradation pathway rather than reductive dechlorination. Moreover, the produced ATZ degradation intermediates could be further adsorbed by Fe/C-800, mitigating potential secondary pollution. Thus, iron-crosslinked alginate derived Fe/C composites can be an excellent alternative for nZVI in organics-polluted water treatment with great reactivity and wide pH applicability.

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