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1.
Gut Microbes ; 16(1): 2340487, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38626129

RESUMO

Obesity is becoming a major global health problem in children that can cause diseases such as type 2 diabetes and metabolic disorders, which are closely related to the gut microbiota. However, the underlying mechanism remains unclear. In this study, a significant positive correlation was observed between Prevotella copri (P. copri) and obesity in children (p = 0.003). Next, the effect of P. copri on obesity was explored by using fecal microbiota transplantation (FMT) experiment. Transplantation of P. copri. increased serum levels of fasting blood glucose (p < 0.01), insulin (p < 0.01) and interleukin-1ß (IL-1ß) (p < 0.05) in high-fat diet (HFD)-induced obese mice, but not in normal mice. Characterization of the gut microbiota indicated that P. copri reduced the relative abundance of the Akkermansia genus in mice (p < 0.01). Further analysis on bile acids (BAs) revealed that P. copri increased the primary BAs and ursodeoxycholic acid (UDCA) in HFD-induced mice (p < 0.05). This study demonstrated for the first time that P. copri has a significant positive correlation with obesity in children, and can increase fasting blood glucose and insulin levels in HFD-fed obese mice, which are related to the abundance of Akkermansia genus and bile acids.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Obesidade Pediátrica , Prevotella , Humanos , Criança , Animais , Camundongos , Insulina , Ácidos e Sais Biliares/farmacologia , Glicemia , Camundongos Obesos , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL
2.
Vet Q ; 44(1): 1-17, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38557401

RESUMO

This study evaluates the effects of dietary Chinese herb ultrafine powder (CHUP) supplementation in late-phase laying hens on the quality and nutritional values of eggs. A total of 576 Xinyang black-feather laying hens (300-day-old) were randomly allocated into eight groups for a 120-day feeding trial. Each group contained eight replicates with nine hens per replicate. The experimental groups included the control (basal diet) and different levels of CHUP groups (details in 'Materials and methods'). The results showed that the eggshell strength was increased (p < 0.05) in the L, LF, L-LF, L-T, and LF-T groups on day 60 of the trial. In addition, the plasma estradiol level in the L-LF, LF-T, and L-LF-T groups and unsaturated fatty acids concentrations in egg yolk of the CHUP groups (except LF-T group) were increased, whereas total cholesterol (T, L-LF, L-T, and L-LF-T groups) in egg yolk and the atherogenicity (T, L-T, and L-LF-T groups) and thrombogenicity (T, L-LF, L-T, and L-LF-T groups) indexes were decreased (p < 0.05) on day 60 of the trial compared with the control group. Moreover, bitter amino acids in egg albumen were decreased (p < 0.05) in the L-LF group on day 60 and the L-LF-T group on day 120 of the trial. Collectively, these findings indicate that dietary CHUP supplementation could improve eggshell quality and increase plasma reproductive hormone, fatty acid and amino acid composition, and nutritional values of eggs, especially L-LF and L-LF-T.


Assuntos
Ração Animal , Galinhas , Animais , Feminino , Pós/análise , Pós/farmacologia , Ração Animal/análise , Óvulo , Gema de Ovo/química , Dieta/veterinária , Aminoácidos , Suplementos Nutricionais
3.
Food Funct ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573228

RESUMO

This study elucidates the mechanism of obesity-related adverse pregnancy outcomes and further investigates the effect of resveratrol on reproductive performance in a short- or long-term HFD-induced obese mouse model. Results show that maternal weight had a significant positive correlation with litter mortality in mice. A long-term HFD increased body weight and litter mortality with decreased expression of uterine cytochrome oxidase 4 (COX4), which was recovered by resveratrol in mice. Moreover, HFD decreased the expression of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), nuclear respiratory factors-1 (Nrf-1), and phosphorylated adenosine 5'-monophosphate (AMP)-activated protein kinase (p-AMPK) and increased the expression of phosphorylated extracellular regulated protein kinases (p-ERK) in the uterus. Resveratrol, a polyphenol that can directly bind to the ERK protein, suppressed the phosphorylation of ERK, increased the expression of p-AMPK, PGC-1α and Nrf-1, and decreased litter mortality in mice.

4.
PLoS One ; 19(4): e0298590, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578739

RESUMO

In power electronics systems, system design and operation often involve multiple time and space scales, ranging from nanosecond switching dynamics to hour-level system operation behavior. Due to the complexity of these systems and the rise of wide-gap semiconductor technology, a series of multi-scale phenomena have emerged that are difficult to ignore. The high frequency of switching operations makes multi-scale effects particularly significant, including the fast dynamic response of the power loop, EMI, and heat conduction problems. They are key factors that must be considered in the design to ensure the efficient and reliable operation of power electronic devices. This study proposes the construction and simulation of a joint scale model for power electronic converters based on wavelet decomposition and reconstruction algorithms to address the multi-scale phenomenon and limitations of single-scale power electronic converters. Firstly, a joint scale model for power electronic converters at both macro and micro-scales was established, targeting both single-scale models and simple combinations of multiple scale models for power electronic converters. The traditional single-scale model is sufficient to describe the average behavior of the converter, but it has serious limitations in capturing fast transient processes and high-frequency switching behavior in power electronic systems. These limitations often manifest themselves when there is a need to capture fine timescales of detail. By transforming between the time domain and the frequency domain, wavelet decomposition enables the model to capture both macroscopic average characteristics and microscopic transient dynamics. The wavelet reconstruction algorithm can simulate all kinds of fast changes in the actual working process more accurately and compress irrelevant information while retaining key signal features, so as to optimize the simulation performance of the model. Secondly, this algorithm is used to analyze BC in short time scale. Finally, the short time scale characteristics of power electronic converters are analyzed. Experimental results show that the fusion of wavelet decomposition and reconstruction algorithm enhances the accuracy of the power electronic converter model and improves the performance of the system. The model achieves an error reduction of nearly 3% in the calculation step size of 10-7s, which has a significant impact on the high precision requirements of high-frequency operations. In addition, the optimal calculation step size of 8×10-8s achieves an error reduction of more than 14%, making an important contribution to the transient analysis and fine structure simulation. The wavelet algorithm can improve the accuracy of multi-scale modeling in power electronic system and reduce the simulation time. The reduction of error not only shows the improvement of the accuracy of the model, but also shows its practical significance in the design and test of the actual power electronic system. The reduction in error reveals the ability to more accurately predict and mitigate potential performance problems in matching tests with actual hardware, as well as its ability to adapt to emerging wide bandgap semiconductor materials and structures.


Assuntos
Algoritmos , Eletrônica , Simulação por Computador , Frequência Cardíaca
5.
Front Psychol ; 15: 1333958, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440244

RESUMO

In the service industry, highway toll collectors serve as a distinctive frontline workforce who frequently encounter mistreatment from customers. Unfortunately, these behaviors have not received the attention and resolution they deserve, resulting in significant physical and psychological stress for toll collectors and exacerbating turnover rates. The study highlights how customer mistreatment affects toll collectors' turnover intentions by performing the sequential mediating roles of stress symptoms and affective commitment and assumes that neuroticism exacerbates the stress symptoms resulting from customer mistreatment based on affective events theory. The model was tested using data collected from 230 highway toll collectors in Zhuhai, China. All hypotheses received support. This study holds both theoretical and practical implications for future research.

6.
Anim Nutr ; 16: 147-157, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38357574

RESUMO

This study evaluated the effects of flavonoids from mulberry leaves (FML) on plasma biochemical indices, serum activities of lipid metabolism-related enzymes, fat morphology, fatty acid composition, and lipid metabolism in different adipose tissues of finishing pigs. We used 120 Chinese hybrid barrows of Berkshire and Bama mini-pigs with an average initial body weight of 45.11 ± 4.23 kg. The pigs were randomly assigned to five treatment groups and fed a control diet based on corn, soybean meal, and wheat bran or a control diet supplemented with 0.02%, 0.04%, 0.08%, or 0.16% FML. Each experimental group had six replicates (pens), with four pigs per pen. After a 7-d adaptation period, the feeding trial was conducted for 58 d. Blood and adipose tissue samples were collected from 30 pigs (one pig per pen) at the end of the test. The results showed that FML supplementation significantly decreased the feed intake to body gain ratio, the plasma concentrations of total cholesterol and free fatty acids, and the serum activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase (linear or quadratic effects, P < 0.05), and decreased the plasma triglyceride concentration (quadratic, P = 0.07). Increasing FML supplementation increased the average daily gain and serum activities of lipoprotein lipase (linear and quadratic effects, P < 0.05) and adipose triglyceride lipase (linear, P < 0.05). Dietary FML supplementation decreased the adipocyte area in the dorsal subcutaneous adipose (DSA) tissue of finishing pigs (linear, P = 0.05) and increased the adipocyte area in the visceral adipose tissue (quadratic, P < 0.01). Increasing FML supplementation decreased the C20:1 content in DSA, abdominal subcutaneous adipose, and visceral adipose tissues of finishing pigs (P < 0.05) and increased the C18:3n3 and n-3 PUFA contents (P < 0.05). The lipid metabolism genes were regulated by the PPARγ-LXRα-ABCA1 signaling pathway, and their expressions differed in different adipose tissues. These findings suggest that FML improved growth performance, regulated lipid metabolism, inhibited fat production, and improved fatty acid distribution in the adipose tissue of finishing pigs, thereby improving pig fat's nutritional quality and health value.

7.
BMC Anesthesiol ; 24(1): 13, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172775

RESUMO

BACKGROUND: The primary purpose of this study was to investigate the predictive value of alterations in cervical artery hemodynamic parameters induced by a simulated end-inspiratory occlusion test (sEIOT) measured by ultrasound for predicting postinduction hypotension (PIH) during general anesthesia. METHODS: Patients undergoing gastrointestinal tumor resection under general anesthesia were selected for this study. Ultrasound has been utilized to assess hemodynamic parameters in carotid artery blood flow before induction, specifically focusing on variations in corrected flow time (ΔFTc) and peak blood flow velocity (ΔCDPV), both before and after sEIOT. Anesthesia was induced by midazolam, sufentanil, propofol, and rocuronium, and blood pressure (BP) and heart rate (HR) were recorded within the first 10 min following endotracheal intubation. PIH was defined as fall in systolic blood pressure (SBP) or mean arterial pressure (MAP) by > 30% of baseline or MAP to < 60 mm Hg. RESULTS: The area under the receiver operating characteristic curves (AUC) for carotid artery ΔFTc was 0.88 (95%CI, 0.81 to 0.96; P < 0.001), and the optimal cutoff value was -16.57%, with a sensitivity of 91.4% and specificity of 77.60%. The gray zone for carotid artery ΔFTc was -16.34% to -15.36% and included 14% of the patients. The AUC for ΔCDPV was 0.54, with an optimal cutoff value of -1.47%. The sensitivity and specificity were calculated as 55.20% and 57.10%, respectively. CONCLUSION: The corrected blood flow time changes in the carotid artery induced by sEIOT can predict hypotension following general anesthesia-induced hypotension, wherein ΔFTc less than 16.57% is the threshold. TRIAL REGISTRATION: Chinese Clinical Trial Registry ( www.chictr.org.cn ; 20/06/2023; ChiCTR2300072632).


Assuntos
Hipotensão , Humanos , Hipotensão/diagnóstico por imagem , Hipotensão/etiologia , Hemodinâmica , Pressão Sanguínea/fisiologia , Anestesia Geral/efeitos adversos , Artérias Carótidas
8.
Phys Rev Lett ; 132(1): 011401, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38242677

RESUMO

We investigate the detectability of gravitational waves that have been lensed by a spinless stellar-mass black hole, with respect to the advanced LIGO. By solving the full relativistic linear wave equations in the spacetime of a Schwarzschild black hole, we find that the strong gravity can create unique signals in the lensed waveform, particularly during the merger and ring-down stages. The differences in terms of fitting factor between the lensed waveform and best-fitted unlensed general relativity template with spin precession and higher-order multipoles are greater than 5% for the lens black hole mass within 70M_{⊙}

9.
J Nutr Biochem ; 124: 109491, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37865382

RESUMO

Weaning is one of the major factors that cause stress and intestinal infection in infants and in young animals due to an immature intestine and not fully developed immune functions. Pectin (PEC), a prebiotic polysaccharide, has attracted considerable attention in intestinal epithelial signaling and function via modulation of the microbial community. A total of 16 weaned piglets (21-d-old) were randomly assigned into two groups: control group and PEC group. Supplementation of 5% pectin improved intestinal mucosal barrier function by modulating the composition of the bile acid pool in piglets. Specifically, piglets in PEC group had less serum D-lactate content and alkaline phosphatase activity. In the ileum, dietary pectin increased the number of crypt PAS/AB-positive goblet cells and the mRNA expressions of MUC2, ZO-1, and Occludin. Piglets in PEC group displayed a decreased abundance of Enterococcus (2.71 vs. 65.92%), but the abundances of Lactobacillus (30.80 vs. 7.93%), Streptococcus (21.41 vs. 14.81%), and Clostridium_sensu_stricto_1 (28.34 vs. 0.01%) were increased. Elevated concentrations of bile acids especially hyocholic acid species (HCAs) including HCA, HDCA, and THDCA were also observed. Besides, correlation analysis revealed that dietary pectin supplementation may have beneficial effects through stimulation of the crosstalk between gut microbes and bile acid synthesis within the enterohepatic circulation. Thus, dietary pectin supplementation exhibited a further positive effect on the healthy growth and development of weaned piglets. These findings suggest pectin supplementation as the prebiotic is beneficial for gut health and improvement of weaned stress via regulating microbiota and bile acid metabolism.


Assuntos
Suplementos Nutricionais , Humanos , Animais , Suínos , Suplementos Nutricionais/análise , Pectinas/farmacologia , Dieta , Ácidos e Sais Biliares , Desmame
10.
Int Immunopharmacol ; 126: 111153, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37979451

RESUMO

To investigate the regulatory effects of Chito-oligosaccharide (COS) on the anti-oxidative, anti-inflammatory, and MAPK signaling pathways. A total of 40 28-day-old weaned piglets were randomly allotted to 4 equal groups [including the control group, lipopolysaccharide (LPS) group, COS group, and COS*LPS group]. On the morning of d 14 and 21, piglets were injected with saline or LPS. At 2 h post-injection, whole blood samples were collected on d 14 and 21, and small intestine and liver samples were collected and analyzed on d 21. The results showed that COS inhibited the LPS-induced increase of malondialdehyde (MDA) concentration and hepatic TNF-α cytokines. COS significantly increased the serum total antioxidant capability (T-AOC) value on d 14, and total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) activities in both serum and liver on d 21. Furthermore, it increased hepatic catalase (CAT) activity. COS also increased the LPS-induced decrease in serum IgG concentrations. Immunohistochemical analysis results showed that COS significantly increased the jejunal and ileal Caspase 3, and ileal CD4+ values challenged by LPS. Dietary COS decreased the LPS-induced jejunal and ileal BAX and CCL2 mRNA levels, markedly decreased ileal COX2 and SOD1 mRNA levels, while increasing ileal iNOS. Furthermore, COS significantly increased the LPS-induced jejunal and ileal p-P38 and MyD88, as well as jejunal P38, while it effectively suppressed jejunal JNK1, and jejunal and ileal JNK2, p-JNK1, and p-JNK2 protein expressions. These results demonstrated that COS could be beneficial by attenuating LPS-challenged intestinal inflammation via regulating mitochondrial apoptotic and MAPK signaling pathways.


Assuntos
Lipopolissacarídeos , Transdução de Sinais , Animais , Suínos , Lipopolissacarídeos/farmacologia , Antioxidantes/metabolismo , RNA Mensageiro/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Oligossacarídeos , Suplementos Nutricionais/análise
11.
J Control Release ; 366: 261-281, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38161032

RESUMO

Vascular smooth muscle cells (VSMCs) have emerged as pivotal contributors throughout all phases of atherosclerotic plaque development, effectively dispelling prior underestimations of their prevalence and significance. Recent lineage tracing studies have unveiled the clonal nature and remarkable adaptability inherent to VSMCs, thereby illuminating their intricate and multifaceted roles in the context of atherosclerosis. This comprehensive review provides an in-depth exploration of the intricate mechanisms and distinctive characteristics that define VSMCs across various physiological processes, firmly underscoring their paramount importance in shaping the course of atherosclerosis. Furthermore, this review offers a thorough examination of the significant strides made over the past two decades in advancing imaging techniques and therapeutic strategies with a precise focus on targeting VSMCs within atherosclerotic plaques, notably spotlighting meticulously engineered nanoparticles as a promising avenue. We envision the potential of VSMC-targeted nanoparticles, thoughtfully loaded with medications or combination therapies, to effectively mitigate pro-atherogenic VSMC processes. These advancements are poised to contribute significantly to the pivotal objective of modulating VSMC phenotypes and enhancing plaque stability. Moreover, our paper also delves into recent breakthroughs in VSMC-targeted imaging technologies, showcasing their remarkable precision in locating microcalcifications, dynamically monitoring plaque fibrous cap integrity, and assessing the therapeutic efficacy of medical interventions. Lastly, we conscientiously explore the opportunities and challenges inherent in this innovative approach, providing a holistic perspective on the potential of VSMC-targeted strategies in the evolving landscape of atherosclerosis research and treatment.


Assuntos
Aterosclerose , Calcinose , Placa Aterosclerótica , Humanos , Músculo Liso Vascular , Aterosclerose/diagnóstico por imagem , Aterosclerose/tratamento farmacológico , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/tratamento farmacológico , Terapia Combinada , Placa Amiloide
12.
Anim Nutr ; 15: 341-349, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38053801

RESUMO

Rosemary extracts have been widely used as feed additives in recent years. This study aimed to investigate the effects of rosmarinic acid (RA) and ursolic acid (UA), the main active components of rosemary, on growth performance, meat quality and lipid metabolism in finishing pigs. A total of 72 finishing pigs (Landrace; initial age of 150 d) were randomly divided into 3 treatments with 8 replicates of 3 pigs each, and fed a basal diet or diet containing 500 mg/kg of RA or UA. The results showed that dietary supplementation of RA or UA had no significant effect on the growth performance and carcass traits of finishing pigs (P > 0.05). However, both RA and UA significantly increased the triglyceride (TG) level in soleus muscle (P < 0.001). Supplementation of RA increased the expression of genes related to lipogenesis and transport including fatty acid synthase (FAS) (P < 0.001), sterol regulatory element binding protein-1c (SREBP1c) (P < 0.001) and peroxisome proliferator-activated receptor γ (PPARγ) (P < 0.05), while UA increased the expression of fatty acid transport protein 1 (FATP1), a gene related to lipid uptake (P < 0.05). However, RA reduced the expression of adipogenesis-related gene acetyl-coenzyme A carboxylase α (ACCα) (P < 0.01). Characterization of cecal microbiota indicated that RA increased the microbial richness (chao 1, P < 0.001) and diversity (observed species, P < 0.01). Further analysis of the genera revealed that RA increased the relative abundance of Bacteroides and g-UCG-005 (P < 0.05), and UA enriched Prevotella (P < 0.001). Correlation analysis showed that g-UCG-005 was positively correlated with the expression of FAS, carnitine palmitoyl transferase 1B (CPT1B), SREBP1c and PPARγ (P < 0.01). In conclusion, dietary supplementation of RA or UA may increase fat deposition in muscle of finishing pigs by regulating lipid metabolism and gut microbiota.

13.
ACS Nano ; 17(19): 19144-19154, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37772918

RESUMO

Electronic structure defines the conductivity and ion absorption characteristics of a functional electrode, significantly affecting the charge transfer capability in batteries, while it is rarely thought to be involved in mesoscopic volume and diffusion kinetics of the host lattice for promoting ion storage. Here, we first correlate the evolution in electronic structure of the Mo6S8 cathode with the ability to bound volume expansion and accelerate diffusion kinetics for high-performance aqueous Cu2+ storage. Operando synchrotron energy-dispersive X-ray absorption spectroscopy reveals that accumulative delocalized Mo 4d electrons enhance the Mo-Mo interaction with distinctly contracting and uniformizing Mo6 clusters during the reduction of Mo6S8, which potently restrain lattice expansion and release space to promote Cu2+ diffusion kinetics. Operando synchrotron X-ray diffraction and comprehensive characterizations further validate the structural and electrochemical properties induced by the Cu2+ intercalation electronic structure, endowing the Mo6S8 cathode a high specific capacity with small volume expansion, fast ions diffusion, and long-term cycling stability.

14.
Structure ; 31(11): 1463-1472.e2, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37652002

RESUMO

The type II restriction endonuclease Sau3AI cleaves the sequence 5'-GATC-3' in double-strand DNA producing two sticky ends. Sau3AI cuts both DNA strands regardless of methylation status. Here, we report the crystal structures of the active site mutant Sau3AI-E64A and the C-terminal domain Sau3AI-C with a bound GATC substrate. Interestingly, the catalytic site of the N-terminal domain (Sau3AI-N) is spatially blocked by the C-terminal domain, suggesting a potential self-inhibition of the enzyme. Interruption of Sau3AI-C binding to substrate DNA disrupts Sau3AI function, suggesting a functional linkage between the N- and C-terminal domains. We propose that Sau3AI-C behaves as an allosteric effector binding one GATC substrate, which triggers a conformational change to open the N-terminal catalytic site, resulting in the subsequent GATC recognition by Sau3AI-N and cleavage of the second GATC site. Our data indicate that Sau3AI and UbaLAI might represent a new subclass of type IIE restriction enzymes.


Assuntos
Clivagem do DNA , DNA , DNA/metabolismo , Enzimas de Restrição do DNA/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/química , Metilação
15.
Environ Sci Pollut Res Int ; 30(43): 97531-97544, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37594715

RESUMO

Groundwater nitrate concentrations cannot be effectively diluted in an oasis of desert hinterland without direct recharge from external rivers. Therefore, there is an urgent need to understand the relationship between groundwater nitrate concentration and the groundwater recharge process. Using hydrochemicals, stable isotopes, LUCC, and combining these with the MixSIAR model, the distributions of groundwater nitrate concentration in the Dengmaying Basin (DMYB) in 2006 and 2020 were obtained. The contributions of groundwater recharge and nitrate sources were also quantified. With the development of agriculture in the DMYB, groundwater irrigation leakage has gradually become a crucial recharge source of groundwater, with a recharge proportion reaching 30.3%. From 2006 to 2020, under the influence of well irrigation and agricultural fertilization, the groundwater nitrate concentration in the DMYB increased significantly, with an increased range of 1.3 ~ 14.3 mg L-1. Moreover, the δ15N-NO3- and δ18O-NO3- values of nitrate in cultivated soil water were similar to those in groundwater, which also proves the process of carrying nitrate from the vadose zone into groundwater by irrigation water. The contribution of anthropogenic sources (54.9%) to groundwater nitrate exceeded that of natural sources (45.1%) to groundwater nitrate in the DMYB. These results indicate that the potential for nitrate pollution in groundwater must be considered, even in desert oases.


Assuntos
Água Subterrânea , Nitratos , China , Agricultura , Água
16.
Sci Bull (Beijing) ; 68(18): 2115-2124, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37567812

RESUMO

The systematic decline of rural areas in the process of rapid urbanization has become a global trend, creating greater challenges for sustainable rural development. As the spatial projection of socio-economic development and living environment in rural areas, the continuous tracking of rural settlements (RUS) is crucial to quantify the imbalance of rural development. However, consistent information on RUS is highly needed but is quite deficient in current research. In this study, a cost-effective mapping model was proposed to produce an annual RUS dataset in the rapid urbanization region of Beijing-Tianjin-Hebei (BTH) in North China during 1990-2020, and the temporal-spatial regularity of RUS changes was further analyzed. The location-based and the area-based comparison verified the effectiveness of our model, with a mean overall accuracy of 85% and a mean correlation value of 0.88, respectively. The total area of RUS in the BTH region increased by 2561 km2 from 1990 to 2020, while the average size of RUS remained stable after 2005. The annual change trends in RUS appeared with increasing and decreasing accounting for 76.33% and 23.67%, respectively. The centroids of RUS in Tianjin and Hebei have moved closer to Beijing, while those in Beijing have moved away from the former. Notably, we have identified 56.3% counties in the BTH region belong to the "Convex-I" change type in RUS. In general, our work can help to consistently quantify the spatiotemporal patterns of RUS in a cost-effective way, providing more explicit spatial information and continuous temporal information for rural residential land management.

17.
PLoS One ; 18(7): e0288324, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37506066

RESUMO

An energy calculation parameter named the energy dissipation degree (RUd) is introduced based on the analysis of the energy dissipation mechanism and energy evolution characteristics during conventional triaxial tests of the granite of Shuangjiangkou. The deviatoric stress‒strain curve of rock can be divided into five stages using four stress thresholds (crack closure stress σcc, crack initiation stress σci, damage stress σcd and peak stress σp), which also correspond to the four RUd thresholds (RUdc, RUdi, RUdd and RUdp) on the energy dissipation degree-strain curve. A given stress threshold increases with increasing confining pressure; however, a given RUd threshold is basically stable under different confining pressures. Then, a new criterion for dividing the excavation damaged zones (EDZs) in the rock surrounding underground caverns based on the monotonically increasing characteristics of the energy dissipation degree‒axial strain relationship curve is proposed, and it allows for the classification of the surrounding rock into five types of zones through quantitative analysis of the RUd thresholds. Based on the criterion for dividing the EDZs of the surrounding rock mass of the underground cavern, the EDZs of the surrounding rocks of the underground cavern group of the Shuangjiangkou Hydropower Station are analyzed. The distribution characteristics of the EDZs of the rock surrounding underground caverns obtained by numerical simulation calculations based on RUd are basically the same as those obtained by in situ elastic wave tests. However, the RUd-based method for classifying the EDZs of the surrounding rock has the obvious advantage of being able to probe the boundaries of the undamaged zone (UDZ) of the surrounding rock more explicitly, while the method based on wave velocity testing is not sufficiently explicit. The damage zoning of the surrounding rock based on RUd can provide support design advice for the excavation of the surrounding rock, such as the support method, the length of the free section and anchor section of the prestressing anchor, etc.


Assuntos
Cavernas , Planejamento de Cidades , Cognição , Simulação por Computador , Pressão
18.
Gut Microbes ; 15(1): 2238959, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37505920

RESUMO

Gut microbiota-diet interaction has been identified as a key factor of metabolic associated fatty liver disease (MAFLD). Recent studies suggested that dietary polyphenols may protect against MAFLD by regulating gut microbiota; however, the underlying mechanisms remain elusive. We first investigated the effects of cyanidin 3-glucoside and its phenolic metabolites on high-fat diet induced MAFLD in C57BL/6J mice, and protocatechuic acid (PCA) showed a significant positive effect. Next, regulation of PCA on lipid metabolism and gut microbiota were explored by MAFLD mouse model and fecal microbiota transplantation (FMT) experiment. Dietary PCA reduced intraperitoneal and hepatic fat deposition with lower levels of transaminases (AST & ALT) and inflammatory cytokines (IL-1ß, IL-2, IL-6, TNF-α & MCP-1), but higher HDL-c/LDL-c ratio. Characterization of gut microbiota indicated that PCA decreased the Firmicutes/Bacteroidetes ratio mainly by reducing the relative abundance of genus Enterococcus, which was positively correlated with the levels of LDL-c, AST, ALT and most of the up-regulated hepatic lipids by lipidomics analysis. FMT experiments showed that Enterococcus faecalis caused hepatic inflammation, fat deposition and insulin resistance with decreased expression of carnitine palmitoyltransferase-1 alpha (CPT1α), which can be reversed by PCA through inhibiting Enterococcus faecalis. Transcriptomics analysis suggested that Enterococcus faecalis caused a significant decrease in the expression of fibroblast growth factor 1 (Fgf1), and PCA recovered the expression of Fgf1 with insulin-like growth factor binding protein 2 (Igfbp2), insulin receptor substrate 1 (Irs1) and insulin receptor substrate 2 (Irs2). These results demonstrated that high proportion of gut Enterococcus faecalis accelerates MAFLD with decreased expression of CPT1α and Fgf1, which can be prevented by dietary supplementation of PCA.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , LDL-Colesterol , Fator 1 de Crescimento de Fibroblastos/metabolismo , Fator 1 de Crescimento de Fibroblastos/farmacologia , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Fígado/metabolismo , Dieta Hiperlipídica/efeitos adversos
19.
Injury ; 54(8): 110917, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37400327

RESUMO

OBJECTIVE: The objective of this study was to evaluate the biomechanical properties of different internal fixation methods for Maisonneuve fractures under physiological loading conditions. METHODS: Finite element analysis was used to numerically analyze various fixation methods. The study focused on high fibular fractures and included six groups of internal fixation: high fibular fracture without fixation + distal tibiofibular elastic fixation (group A), high fibular fracture without fixation + distal tibiofibular strong fixation (group B), high fibular fracture with 7-hole plate internal fixation + distal tibiofibular elastic fixation (group C), high fibular fracture with 7-hole plate internal fixation + distal tibiofibular strong fixation (group D), high fibular fracture with 5-hole plate internal fixation + distal tibiofibular elastic fixation (group E), and high fibular fracture with 5-hole plate internal fixation + distal tibiofibular strong fixation (group F). The finite element method was employed to simulate and analyze the different internal fixation models for the six groups, generating overall structural displacement and Von Mises stress distribution maps during slow walking and external rotation motions. RESULTS: Group A demonstrated the best ankle stability under slow walking and external rotation, with reduced tibial and fibular stress after fibular fracture fixation. Group D had the least displacement and most stability, while group A had the largest displacement and least stability. Overall, high fibular fracture fixation improved ankle stability. In slow walking, groups D and A had the least and greatest interosseous membrane stress. Comparing 5-hole plate (E/F) and 7-hole plate (C/D) fixation, no significant differences were found in ankle strength or displacement under slow walking or external rotation. CONCLUSION: Combining internal fixation for high fibular fractures with elastic fixation of the lower tibia and fibula is optimal for orthopedic treatment. It yields superior outcomes compared to no fibular fracture fixation or strong fixation of the lower tibia and fibula, especially during slow walking and external rotation. To minimize nerve damage, a smaller plate is recommended. This study strongly advocates for the clinical use of 5-hole plate internal fixation for high fibular fractures with elastic fixation of the lower tibia and fibula (group E).


Assuntos
Traumatismos do Tornozelo , Fraturas da Fíbula , Humanos , Análise de Elementos Finitos , Traumatismos do Tornozelo/diagnóstico por imagem , Traumatismos do Tornozelo/cirurgia , Articulação do Tornozelo/cirurgia , Fixação Interna de Fraturas/métodos , Fíbula/cirurgia
20.
Front Vet Sci ; 10: 1185191, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377951

RESUMO

The purpose of this study is to reveal the effects of different particle sizes of rice straw on the rumen protozoa count, nutrient disappearance rate, rumen fermentation, and microbial community in a rumen simulation technique (RUSITEC) system. In this experiment, a single-factor random trial design was adopted. According to the different particle sizes of rice straw, there were three treatments with three replies in each treatment. Three kinds of goat total mixed ration (TMR), with the same nutrients were used to carry out a 10 days in vitro fermentation experiment using the rumen simulation system developed by Hunan Agricultural University, including 6 days the pretrial period and 4 days formal period. This study found that the organic matter disappearance rate, concentrations of total volatile fatty acids (VFAs), acetate, propionate, and iso-butyrate were greatest in the 4 mm group (p < 0.05). There were no significant differences in the alpha diversity, among the three groups (p > 0.05). The relative abundance of Treponema and Ruminococcus of the 2 mm group increased; the relative abundance of Butyrivibrio and Prevotella in samples increased in the 4 mm group. In addition, the results of correlation analysis showed that Prevotella and Ruminococcus was positively correlated with butyrate, ammonia-N, dOM and d ADF (p < 0.05) and negatively correlated with valerate (p < 0.05); Oscillospira was positively correlated with valerate (p < 0.01) and negatively correlated with propionate, butyrate, ammonia-N, dOM and dADF (p < 0.05). The present results imply that compared to the other groups, rice straw particle size of 4 mm may improve the disappearance rate of nutrients and promote the production of volatile fatty acids by regulating ruminal microorganisms.

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