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Federated Learning (FL), a promising deep learning paradigm extensively deployed in Vehicular Edge Computing Networks (VECN), allows a distributed approach to train datasets of nodes locally, e.g., for mobile vehicles, and exchanges model parameters to obtain an accurate model without raw data transmission. However, the existence of malicious vehicular nodes as well as the inherent heterogeneity of the vehicles hinders the attainment of accurate models. Moreover, the local model training and model parameter transmission during FL exert a notable energy burden on vehicles constrained in resources. In view of this, we investigate FL client selection and resource management problems in FL-enabled UAV-assisted Vehicular Networks (FLVN). We first devise a novel reputation-based client selection mechanism by integrating both data quality and computation capability metrics to enlist reliable high-performance vehicles. Further, to fortify the FL reliability, we adopt the consortium blockchain to oversee the reputation information, which boasts tamper-proof and interference-resistant qualities. Finally, we formulate the resource scheduling problem by jointly optimizing the computation capability, the transmission power, and the number of local training rounds, aiming to minimize the cost of clients while guaranteeing accuracy. To this end, we propose a reinforcement learning algorithm employing an asynchronous parallel network structure to achieve an optimized scheduling strategy. Simulation results show that our proposed client selection mechanism and scheduling algorithm can realize reliable FL with an accuracy of 0.96 and consistently outperform the baselines in terms of delay and energy consumption.

Ridge-furrow film mulching has been proven to be an effective water-saving and yield-improving planting pattern in arid and semi-arid regions. Drought is the main factor limiting the local agricultural production in the Loess Plateau of China. In this study, we tried to select a suitable ridge-furrow mulching system to improve this situation. A two-year field experiment of summer maize (Zea maysL.) during the growing seasons of 2017 and 2018 was conducted to systematically analyze the effects of flat planting with no film mulching (CK), ridge-furrow with ridges mulching and furrows bare (RFM), and double ridges and furrows full mulching (DRFFM) on soil temperature, soil water storage (SWS), root growth, aboveground dry matter, water use efficiency (WUE), and grain yield. Both RFM and DRFFM significantly increased soil temperature in ridges, while soil temperature in furrows for RFM and DRFFM was similar to that for CK. The largest SWS was observed in DRFFM, followed by RFM and CK, with significant differences among them. SWS was lower in ridges than in furrows for RFM. DRFFM treatment kept soil water in ridges, resulting in higher SWS in ridges than in furrows after a period of no water input. Across the two growing seasons, compared with CK, RFM increased root mass by 10.2% and 19.3% at the jointing and filling stages, respectively, and DRFFM increased root mass by 7.9% at the jointing stage but decreased root mass by 6.0% at the filling stage. Over the two growing seasons, root length at the jointing and filling stages was respectively increased by 75.4% and 58.7% in DRFFM, and 20.6% and 30.2% in RFM. Relative to the jointing stage, the increased proportions of root mass and length at the filling stage were respectively 42.8% and 94.9% in DRFFM, 63.2% and 115.1% in CK, and 76.7% and 132.1% in RFM, over the two growing seasons, showing that DRFFM slowed down root growth while RFM promoted root growth at the later growth stages. DRFFM treatment increased root mass and root length in ridges and decreased them in 0–30 cm soil layer, while RFM increased them in 0–30 cm soil layer. Compared with CK, DRFFM decreased aboveground dry matter while RFM increased it. Evapotranspiration was reduced by 9.8% and 7.1% in DRFFM and RFM, respectively, across the two growing seasons. Grain yield was decreased by 14.3% in DRFFM and increased by 13.6% in RFM compared with CK over the two growing seasons. WUE in CK was non-significantly 6.8% higher than that in DRFFM and significantly 22.5% lower than that in RFM across the two growing seasons. Thus, RFM planting pattern is recommended as a viable water-saving option for summer maize in the Loess Plateau of China.

Limited water resources often result in reduced crop yield and low water productivity (WP). In northwestern China, crop production is generally dependent on precipitation. Therefore, a variety of agricultural rainwater harvesting (ARH) techniques have been used for conserving soil moisture, ameliorating soil environment, increasing crop yield, and improving water use efficiency. A two-year (2013–2015) field experiment was conducted under a typical sub-humid drought-prone climate in Yangling (108°24′E, 34°20′N; 521 m a.s.l.), Shaanxi Province, China, to explore the effects of mulching (same for summer maize and winter wheat) on soil moisture, soil temperature, crop water consumption, and crop yield with a winter wheat/summer maize rotation. Crops were planted in a ridge-furrow pattern and the treatments consisted of a transparent film mulch over the ridges (M1), a crop straw mulch in the furrows (M2), a transparent film mulch over the ridges and a crop straw mulch in the furrows (M3), a black film mulch over the ridges and a crop straw mulch in the furrows (M4), and a control with no mulch (CK). Results showed that M4 was the best treatment for improving soil water storage and content, and decreasing crop water consumption during the summer maize and winter wheat rotation. In both maize and wheat seasons, M1 had a higher soil temperature than M2 and CK, and M3 had a higher soil temperature than M4. In the maize seasons, M4 had the highest yield, WP, and precipitation productivity (PP), with the average values for these parameters increasing by 30.9%, 39.0%, and 31.0%, respectively, compared to those in CK. In the wheat seasons, however, M3 had the highest yield, WP, and PP, with the average values for these parameters being 23.7%, 26.7%, and 23.8% higher, respectively, than those in CK. Annual yield (maize and wheat yields combined) and WP did not differ significantly between M3 and M4. These results suggested that M3 and M4 may thus be the optimal ARH practices for the production of winter wheat and summer maize, respectively, in arid and semi-arid areas.

The aims of this study were to investigate the effects of supplemental N-acetyl-l-cysteine (NAC) on chronic heat stress-induced oxidative stress and inflammation in the ovaries of growing pullets. A total of 120, 12-wk-old, Hy-Line Brown hens were randomly separated into 4 groups with 6 replicates of 5 birds in each group for 21 d. The 4 treatments were as follows: the CON group and CN group were supplemented with basal diet or basal diet with 1 g/kg NAC, respectively; and the HS group and HSN group were heat-stressed groups supplemented with basal diet or basal diet with 1 g/kg NAC, respectively. The results indicated that the ovaries suffered pathological damage due to chronic heat stress and that NAC effectively ameliorated these changes. Compared with the HS group, antioxidant enzyme activities (including SOD, GSH-Px, CAT, and T-AOC) were enhanced, while the MDA contents and the expression levels of HSP70 were decreased in the HSN group. In addition, NAC upregulated the expression levels of HO-1, SOD2, and GST by upregulating the activity of Nrf2 at different time points to mitigate oxidative stress caused by heat exposure. Simultaneously, NAC attenuated chronic heat stress-induced NF-κB pathway activation and decreased the expression levels of the proinflammatory cytokines IL-8, IL-18, TNF-α, IKK-α, and IFN-γ. Cumulatively, our results indicated that NAC could ameliorate chronic heat stress-induced ovarian damage by upregulating the antioxidative capacity and reducing the secretion of proinflammatory cytokines.

The adverse effects of chronic heat stress (CHS)-induced fatty liver syndrome on laying hens during the egg-producing stages have been wildly documented. However, until nowadays, the CHS responses of growing laying hens as well as its alleviating effects of vitamin C are rarely reported. In this study, 12-wk-old laying hens were subjected to CHS at 36 °C for 10 h/d for 3 wk with or without dietary supplementation of 300 mg/kg vitamin C. Results showed that CHS significantly impaired the growth performances and the liver functions of birds, as characterized by reduced feed intake and body weight, increased hepatic lipid accumulation and serum concentrations of TG, ALT, and AST, as well as the abnormal expression patterns of the lipid metabolism-related genes. Vitamin C supplementation successfully mitigated the lipid accumulation, while showing no alleviating effect on the serum contents of ALT or AST, which are two key indicators of liver functions. Metabolomic analysis based on UPLC-Q-TOF/MS identified 173 differential metabolites from the HS and HSV group samples, and they are mainly enriched in the pathways related to the cellular components, vitamin and amino acid metabolism and energy substance metabolism. The results indicate that CHS-induced hepatic lipid deposition in growing laying hens is effectively alleviated by dietary supplementation of vitamin C, which is probably resulted from the alterations of hepatocellular metabolic patterns.The findings in this study not only extend our understandings about the CHS responses of growing laying hens, but also provide new clues and experimental basis for the salvaging of CHS and FLS disease in the poultry industry.Chronic heat stress (CHS)-induced fatty liver syndrome (FLS) is one of the major problems faced in poultry industry. However, the heat stress response as well as the alleviating strategies for growing laying hens is rarely concerned until nowadays. In this study, 12-wk-old laying hens were subjected to the CHS condition with or without dietary supplementation of 300 mg/kg vitamin C, we found that CHS can also remarkably impair the growth performance and liver functions and induce the hepatic lipid metabolism disorders in the growing laying hens. Vitamin C supplementation successfully mitigated the hepatic lipid accumulation, while showed no alleviating effect on the liver functions. Metabolomic analysis further identified 173 differential metabolites between CHS and HSV groups, which are mainly enriched in the pathways including the cellular components, vitamin and amino acid metabolism and the energy substance metabolism. The results suggest that vitamin C supplementation can effectively alleviate the hepatic lipid deposition in growing laying hens under CHS probably through altering their energy metabolism patterns.

The purpose of this study was to explore whether conjugated linoleic acid (CLA) could alleviate fatty liver hemorrhagic syndrome (FLHS) induced by estradiol benzoate intramuscular injection in laying hens. One hundred male Hy-Line white chickens were randomly divided into two groups, namely, the control (CON) and estradiol benzoate (E) groups, and both groups were fed the same basal diet. After injections of estradiol benzoate at 2 mg/kg every two days for a total of 7 times, chickens in the E group showed FLHS symptoms, including liver enlargement, hemorrhage, and steatosis. Then half of the chickens in the E group received an additional diet containing 5000 mg/kg CLA for 8 weeks. The results of morphological observations, hematoxylin and eosin staining, and Oil Red O staining showed that CLA alleviated liver enlargement, hemorrhage, and lipid accumulation in FLHS chickens. In addition, we measured liver function and lipid metabolism indicators, including ALT, AST, TG, TCH, HDL-C, and LDL-C, which further suggested that CLA mitigated the disturbance of serum and liver metabolism in FLHS chickens. Mechanistically, CLA inhibited hepatic de novo lipogenesis, cholesterol synthesis, and TG accumulation and increased TG hydrolysis in FLHS chickens by regulating the gene expression of CD36, ACC, FAS, SCD 1, DGAT2, LIPE, ATGL, CPT1A, SREBP-1c, SREBP-2, PPARγ, and PPARα. Furthermore, CLA ameliorated hepatic oxidative stress and inhibited NF-κB signaling pathway-mediated inflammation in FLHS chickens. In conclusion, CLA regulated lipid metabolism, thus further alleviating oxidative stress and inflammation to alleviate FLHS induced by estrogen in chickens.We successfully replicated the FLHS pathological model by intramuscular injection of estradiol benzoate. Most importantly, dietary CLA alleviated FLHS by alleviating hepatic lipid metabolism disorders, oxidative stress injury, and inflammation.Fatty liver hemorrhagic syndrome (FLHS) has become one of the most common noninfectious diseases that contribute to laying hen mortality. Conjugated linoleic acid (CLA) is a functional polyunsaturated fatty acid with antioxidant and anti-inflammatory properties The purpose of this study was to investigate the effect of CLA on FLHS induced by estradiol benzoate in laying hens. We successfully replicated the FLHS pathological model by intramuscular injection of estradiol benzoate. The results of morphological and histopathological observations showed that CLA alleviated liver lipid accumulation in FLHS chickens. In addition, we measured liver function and lipid metabolism indicators, which further suggested that CLA mitigated the disturbance of serum and liver metabolism in FLHS chickens. Moreover, CLA inhibited hepatic de novo lipogenesis, cholesterol synthesis, and TG accumulation and increased TG hydrolysis in FLHS chickens by regulating related gene expression. Furthermore, CLA ameliorated hepatic oxidative stress and inhibited inflammation in FLHS chickens. In conclusion, CLA regulated lipid metabolism, thus further alleviating oxidative stress and inflammation to alleviate FLHS induced by estrogen in chickens. Our results provide new evidence and insights for applying CLA as an effective treatment for FLHS.

The fatty liver hemorrhage syndrome in laying hens is a disease of lipid metabolism disorders. Importantly, energy sensor AMP-activated protein kinase (AMPK) plays an essential role in homeostasis regulation of liver lipid. The current research aims to investigate the relationship between AMPK signaling pathway and lipid metabolism in laying hen hepatocytes and explore the underlying mechanisms. The steatotic hepatocytes model of laying hen was established and treated with AMPK agonist AICAR and inhibitor compound C. The results showed that the levels of triglyceride, total cholesterol, and low-density lipoprotein cholesterol significantly declined while high-density lipoprotein cholesterol level increased in the AICAR-treated steatosis group compared with the steatosis group. Furthermore, the mRNA levels of liver kinase B1 and AMP-activated protein kinase α1 declined significantly in the steatosis group compared with those in the normal group. However, AMPK activation significantly upregulated the mRNA levels of peroxisome proliferator-activated receptor α and carnitine palmitoyl transferase-1 while downregulated the mRNA levels of acetyl CoA carboxylase, fatty acid synthase, 3-hydroxy-3-methyl glutaryl coenzyme A reductase, Sn-glycerol-3-phosphate acyltransferase, and hepatocyte nuclear factor 4α. These results suggest that activated AMPK signaling pathway increases fatty acid oxidation and reduces lipid synthesis in laying hen hepatocytes, thereby ameliorating liver steatosis.

ABSTRACTBackground: In China, less than one-fifth of multidrug-resistant tuberculosis (MDR-TB) cases are detected. MDR-TB screening is conducted amongst the following five high-risk groups of TB patients: chronic cases, close contacts of MDR-TB patients, patients with treatment failure, relapsed and returned patients, and smear-positive patients at the end of the third month of initial treatment.Objective: To estimate the possibility of detecting MDR-TB cases if only the high-risk screening strategy is applied in China.Methods: A secondary analysis was applied to the surveillance-based longitudinal data of all sputum smear-positive TB patients in Prefecture E and Prefecture W of China from 2013 to 2015. The population attributable risk (PAR) was estimated using odds ratios for five risk factors/predictors and exposure proportions amongst all MDR-TB cases.Results: A total of 3513 TB patients (2807 from Prefecture E and 706 from Prefecture W) were included. Males accounted for 77.91% (2737/3513) of the patients. The average age was 52.5 ± 20.0 years old. Overall, 40.34% (71/176) of MDR-TB patients were from the five high-risk groups during the three-year study period. The detected proportion of MDR-TB cases using the high-risk screening strategy was significantly higher in Prefecture E than in Prefecture W. The PAR% for all five risk factors/predictors was 43.4% (95% CI: 24.6–61.7%), 49.9% (95% CI: 31.3–67.0%), and 30.3% (95% CI: 12.9–50.1%) in Prefecture E and 36.6% (95% CI: 10.4–64.5%), 13.3% (95% CI: −1.7–39.7%), and −82.5% (95% CI: −117.5–−11.2%) in Prefecture W in 2013, 2014, and 2015, respectively. The PAR% for the five specific risk factors/predictors ranged from 0.4% (95% CI: −0.2–4.8%) to 21.0% (95% CI: 13.1–30.0%) in these two prefectures.Conclusion: In general, a high-risk screening strategy would miss more than half of the MDR-TB patients because they do not belong to the five high-risk groups.