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PetroChina lays off 10000 workers in first nine months 被引量:1
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《China Oil & Gas》 CAS 2000年第4期21-21,共1页
关键词 PetroChina lays off 10000 workers in first nine months
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An Analysis of Play It As It Lays from the Perspective of Fromm’s Alienation Theory
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作者 朱叶琴 《海外英语》 2021年第8期233-235,共3页
Joan Didion is an outstanding female writer who has achieved a distinctive position in contemporary literature.Her second novel,Play It As It Lays,is nominated for a National Book Award.Set in Hollywood and Las Vegas,... Joan Didion is an outstanding female writer who has achieved a distinctive position in contemporary literature.Her second novel,Play It As It Lays,is nominated for a National Book Award.Set in Hollywood and Las Vegas,it presents the alienated world through exquisite description of its protagonist Maria.Based on Erich Fromm’s Alienation Theory,this essay attempts to analyze the alienation in the novel from two aspects:first,the novel’s materialistic environment in the 1960s;second,the alienated relationship between spouses as well as between parents and children. 展开更多
关键词 Joan Didion Play It As It lays Erich Fromm Alienation Theory RELATIONSHIP
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Multi-omics analysis reveals the molecular regulatory network underlying the prevention of Lactiplantibacillus plantarum against LPS-induced salpingitis in laying hens 被引量:1
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作者 Dan Song Aike Li +6 位作者 Bingxu Chen Jia Feng Tao Duan Junlin Cheng Lixian Chen Weiwei Wang Yuna Min 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期427-441,共15页
Background Salpingitis is one of the common diseases in laying hen production, which greatly decreases the economic outcome of laying hen farming. Lactiplantibacillus plantarum was effective in preventing local or sys... Background Salpingitis is one of the common diseases in laying hen production, which greatly decreases the economic outcome of laying hen farming. Lactiplantibacillus plantarum was effective in preventing local or systemic inflammation, however rare studies were reported on its prevention against salpingitis. This study aimed to investigate the preventive molecular regulatory network of microencapsulated Lactiplantibacillus plantarum(MLP) against salpingitis through multi-omics analysis, including microbiome, transcriptome and metabolome analyses.Results The results revealed that supplementation of MLP in diet significantly alleviated the inflammation and atrophy of uterus caused by lipopolysaccharide(LPS) in hens(P < 0.05). The concentrations of plasma IL-2 and IL-10 in hens of MLP-LPS group were higher than those in hens of LPS-stimulation group(CN-LPS group)(P < 0.05). The expression levels of TLR2, MYD88, NF-κB, COX2, and TNF-α were significantly decreased in the hens fed diet supplemented with MLP and suffered with LPS stimulation(MLP-LPS group) compared with those in the hens of CN-LPS group(P < 0.05). Differentially expressed genes(DEGs) induced by MLP were involved in inflammation, reproduction, and calcium ion transport. At the genus level, the MLP supplementation significantly increased the abundance of Phascolarctobacterium, whereas decreased the abundance of Candidatus_Saccharimonas in LPS challenged hens(P < 0.05). The metabolites altered by dietary supplementation with MLP were mainly involved in galactose, uronic acid, histidine, pyruvate and primary bile acid metabolism. Dietary supplementation with MLP inversely regulates LPSinduced differential metabolites such as Lyso PA(24:0/0:0)(P < 0.05).Conclusions In summary, dietary supplementation with microencapsulated Lactiplantibacillus plantarum prevented salpingitis by modulating the abundances of Candidatus_Saccharimonas, Phascolarctobacterium, Ruminococcus_torques_group and Eubacterium_hallii_group while downregulating the levels of plasma metabolites, p-tolyl sulfate, o-cresol and N-acetylhistamine and upregulating S-lactoylglutathione, simultaneously increasing the expressions of CPNE4, CNTN3 and ACAN genes in the uterus, and ultimately inhibiting oviducal inflammation. 展开更多
关键词 Laying hen METABOLOME MICROBIOME Microencapsulated Lactiplantibacillus plantarum SALPINGITIS TRANSCRIPTOME
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Coated sodium butyrate ameliorates high‑energy and low‑protein diet induced hepatic dysfunction via modulating mitochondrial dynamics, autophagy and apoptosis in laying hens 被引量:1
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作者 Sasa Miao Tianming Mu +5 位作者 Ru Li Yan Li Wenyan Zhao Jiankui Li Xinyang Dong Xiaoting Zou 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1190-1206,共17页
Background Fatty liver hemorrhagic syndrome(FLHS),a fatty liver disease in laying hens,poses a grave threat to the layer industry,stemming from its ability to trigger an alarming plummet in egg production and usher in... Background Fatty liver hemorrhagic syndrome(FLHS),a fatty liver disease in laying hens,poses a grave threat to the layer industry,stemming from its ability to trigger an alarming plummet in egg production and usher in acute mortality among laying hens.Increasing evidence suggests that the onset and progression of fatty liver was closely related to mitochondria dysfunction.Sodium butyrate was demonstrated to modulate hepatic lipid metabolism,alle-viate oxidative stress and improve mitochondrial dysfunction in vitro and mice models.Nevertheless,there is limited existing research on coated sodium butyrate(CSB)to prevent FLHS in laying hens,and whether and how CSB exerts the anti-FLHS effect still needs to be explored.In this experiment,the FLHS model was induced by administering a high-energy low-protein(HELP)diet in laying hens.The objective was to investigate the effects of CSB on alleviating FLHS with a focus on the role of CSB in modulating mitochondrial function.Methods A total of 288 healthy 28-week-old Huafeng laying hens were arbitrarily allocated into 4 groups with 6 replicates each,namely,the CON group(normal diet),HELP group(HELP diet),CH500 group(500 mg/kg CSB added to HELP diet)and CH750 group(750 mg/kg CSB added to HELP diet).The duration of the trial encompassed a period of 10 weeks.Results The result revealed that CSB ameliorated the HELP-induced FLHS by improving hepatic steatosis and patho-logical damage,reducing the gene levels of fatty acid synthesis,and promoting the mRNA levels of key enzymes of fatty acid catabolism.CSB reduced oxidative stress induced by the HELP diet,upregulated the activity of GSH-Px and SOD,and decreased the content of MDA and ROS.CSB also mitigated the HELP diet-induced inflammatory response by blocking TNF-α,IL-1β,and F4/80.In addition,dietary CSB supplementation attenuated HELP-induced activation of the mitochondrial unfolded protein response(UPRmt),mitochondrial damage,and decline of ATPase activity.HELP diet decreased the autophagosome formation,and downregulated LC3B but upregulated p62 protein expression,which CSB administration reversed.CSB reduced HELP-induced apoptosis,as indicated by decreases in the Bax/Bcl-2,Caspase-9,Caspase-3,and Cyt C expression levels.Conclusions Dietary CSB could ameliorate HELP diet-induced hepatic dysfunction via modulating mitochondrial dynamics,autophagy,and apoptosis in laying hens.Consequently,CSB,as a feed additive,exhibited the capacity to prevent FLHS by modulating autophagy and lipid metabolism. 展开更多
关键词 AUTOPHAGY Coated sodium butyrate Laying hens Lipid metabolism MITOCHONDRIA
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Decreased eggshell strength caused by impairment of uterine calcium transport coincide with higher bone minerals and quality in aged laying hens 被引量:1
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作者 Yu Fu Jianmin Zhou +4 位作者 Martine Schroyen Haijun Zhang Shugeng Wu Guanghai Qi Jing Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1258-1277,共20页
Background Deteriorations in eggshell and bone quality are major challenges in aged laying hens.This study compared the differences of eggshell quality,bone parameters and their correlations as well as uterine physiol... Background Deteriorations in eggshell and bone quality are major challenges in aged laying hens.This study compared the differences of eggshell quality,bone parameters and their correlations as well as uterine physiologi-cal characteristics and the bone remodeling processes of hens laying eggs of different eggshell breaking strength to explore the mechanism of eggshell and bone quality reduction and their interaction.A total of 24074-week-old Hy-line Brown laying hens were selected and allocated to a high(HBS,44.83±1.31 N)or low(LBS,24.43±0.57 N)eggshell breaking strength group.Results A decreased thickness,weight and weight ratio of eggshells were observed in the LBS,accompanied with ultrastructural deterioration and total Ca reduction.Bone quality was negatively correlated with eggshell quality,marked with enhanced structures and increased components in the LBS.In the LBS,the mammillary knobs and effective layer grew slowly.At the initiation stage of eggshell calcification,a total of 130 differentially expressed genes(DEGs,122 upregulated and 8 downregulated)were identified in the uterus of hens in the LBS relative to those in the HBS.These DEGs were relevant to apoptosis due to the cellular Ca overload.Higher values of p62 protein level,caspase-8 activity,Bax protein expression and lower values of Bcl protein expression and Bcl/Bax ratio were seen in the LBS.TUNEL assay and hematoxylin-eosin staining showed a significant increase in TUNEL-positive cells and tissue damages in the uterus of the LBS.Although few DEGs were identified at the growth stage,similar uterine tissue damages were also observed in the LBS.The expressions of runt-related transcription factor 2 and osteocal-cin were upregulated in humeri of the LBS.Enlarged diameter and more structural damages of endocortical bones and decreased ash were observed in femurs of the HBS.Conclusion The lower eggshell breaking strength may be attributed to a declined Ca transport due to uterine tissue damages,which could affect eggshell calcification and lead to a weak ultrastructure.Impaired uterine Ca transport may result in reduced femoral bone resorption and increased humeral bone formation to maintain a higher mineral and bone quality in the LBS. 展开更多
关键词 Bone parameter Calcium transport Eggshell quality Laying hen Tissue damage
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Lactiplantibacillus plantarum FRT4 attenuates high-energy low-protein dietinduced fatty liver hemorrhage syndrome in laying hens through regulating gut-liver axis 被引量:1
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作者 Daojie Li Hongying Cai +5 位作者 Guohua Liu Yunsheng Han Kai Qiu Weiwei Liu Kun Meng Peilong Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1292-1311,共20页
Background Fatty liver hemorrhage syndrome(FLHS)becomes one of the most major factors resulting in the laying hen death for caged egg production.This study aimed to investigate the therapeutic effects of Lactiplantiba... Background Fatty liver hemorrhage syndrome(FLHS)becomes one of the most major factors resulting in the laying hen death for caged egg production.This study aimed to investigate the therapeutic effects of Lactiplantibacillus plan-tarum(Lp.plantarum)FRT4 on FLHS model in laying hen with a focus on liver lipid metabolism,and gut microbiota.Results The FLHS model of laying hens was established by feeding a high-energy low-protein(HELP)diet,and the treatment groups were fed a HELP diet supplemented with differential proportions of Lp.plantarum FRT4.The results indicated that Lp.plantarum FRT4 increased laying rate,and reduced the liver lipid accumulation by regulating lipid metabolism(lipid synthesis and transport)and improving the gut microbiota composition.Moreover,Lp.plan-tarum FRT4 regulated the liver glycerophospholipid metabolism.Meanwhile,“gut-liver”axis analysis showed that there was a correlation between gut microbiota and lipid metabolites.Conclusions The results indicated that Lp.plantarum FRT4 improved the laying performance and alleviated FLHS in HELP diet-induced laying hens through regulating“gut-liver”axis.Our findings reveal that glycerophospholipid metabolism could be the underlying mechanism for the anti-FLHS effect of Lp.plantarum FRT4 and for future use of Lp.plantarum FRT4 as an excellent additive for the prevention and mitigation of FLHS in laying hens. 展开更多
关键词 Fatty liver hemorrhage syndrome Gut microbiota Lactiplantibacillus plantarum FRT4 Laying hens Lipid metabolism
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Effects of different energy levels in low-protein diet on liver lipid metabolism in the late-phase laying hens through the gut-liver axis
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作者 Hong Hu Ying Huang +7 位作者 Anjian Li Qianhui Mi Kunping Wang Liang Chen Zelong Zhao Qiang Zhang Xi Bai Hongbin Pan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2122-2136,共15页
Background The energy/protein imbalance in a low-protein diet induces lipid metabolism disorders in late-phase laying hens.Reducing energy levels in the low-protein diet to adjust the energy-to-protein ratio may impro... Background The energy/protein imbalance in a low-protein diet induces lipid metabolism disorders in late-phase laying hens.Reducing energy levels in the low-protein diet to adjust the energy-to-protein ratio may improve fat deposition,but this also decreases the laying performance of hens.This study investigated the mechanism by which different energy levels in the low-protein diet influences liver lipid metabolism in late-phase laying hens through the enterohepatic axis to guide feed optimization and nutrition strategies.A total of 288 laying hens were randomly allocated to the normal-energy and normal-protein diet group(positive control:CK)or 1 of 3 groups:lowenergy and low-protein diet(LL),normal-energy and low-protein diet(NL),and high-energy and low-protein diet(HL)groups.The energy-to-protein ratios of the CK,LL,NL,and HL diets were 0.67,0.74,0.77,and 0.80,respectively.Results Compared with the CK group,egg quality deteriorated with increasing energy intake in late-phase laying hens fed low-protein diet.Hens fed LL,NL,and HL diets had significantly higher triglyceride,total cholesterol,acetylCo A carboxylase,and fatty acid synthase levels,but significantly lower hepatic lipase levels compared with the CK group.Liver transcriptome sequencing revealed that genes involved in fatty acid beta-oxidation(ACOX1,HADHA,EHHADH,and ACAA1)were downregulated,whereas genes related to fatty acid synthesis(SCD,FASN,and ACACA)were upregulated in LL group compared with the CK group.Comparison of the cecal microbiome showed that in hens fed an LL diet,Lactobacillus and Desulfovibrio were enriched,whereas riboflavin metabolism was suppressed.Cecal metabolites that were most significantly affected by the LL diet included several vitamins,such as riboflavin(vitamin B2),pantethine(vitamin B5 derivative),pyridoxine(vitamin B6),and 4-pyridoxic acid.Conclusion A lipid metabolism disorder due to deficiencies of vitamin B2 and pantethine originating from the metabolism of the cecal microbiome may be the underlying reason for fat accumulation in the liver of late-phase laying hens fed an LL diet.Based on the present study,we propose that targeting vitamin B2 and pantethine(vitamin B5 derivative)might be an effective strategy for improving lipid metabolism in late-phase laying hens fed a low-protein diet. 展开更多
关键词 Cecal microbiome Energy/protein imbalance Late-phase laying hens laying hens Liver lipid metabolism Low-protein diet Multi-omics
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Prevotella and succinate treatments altered gut microbiota,increased laying performance,and suppressed hepatic lipid accumulation in laying hens
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作者 Min Liu Zeyue Kang +4 位作者 Xikang Cao Hongchao Jiao Xiaojuan Wang Jingpeng Zhao Hai Lin 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期844-861,共18页
Background This work aimed to investigate the potential benefits of administering Prevotella and its primary metabolite succinate on performance,hepatic lipid accumulation and gut microbiota in laying hens.Results One... Background This work aimed to investigate the potential benefits of administering Prevotella and its primary metabolite succinate on performance,hepatic lipid accumulation and gut microbiota in laying hens.Results One hundred and fifty 58-week-old Hyline Brown laying hens,with laying rate below 80%and plasma triglyceride(TG)exceeding 5 mmol/L,were used in this study.The hens were randomly allocated into 5 groups and subjected to one of the following treatments:fed with a basal diet(negative control,NC),oral gavage of 3 mL/hen saline every other day(positive control,PC),gavage of 3 mL/hen Prevotella melaninogenica(10^(7)CFU/mL,PM)or 3 mL/hen Prevotella copri(10^(7)CFU/mL,P.copri)every other day,and basal diet supplemented with 0.25%sodium succinate(Succinate).The results showed that PM and P.copri treatments significantly improved laying rate compared to the PC(P<0.05).The amount of lipid droplet was notably decreased by PM,P.copri,and Succinate treatments at week 4 and decreased by P.copri at week 8(P<0.05).Correspondingly,the plasma TG level in Succinate group was lower than that of PC(P<0.05).Hepatic TG content,however,was not significantly influenced at week 4 and 8(P>0.05).PM treatment increased(P<0.05)the mRNA levels of genes PGC-1βand APB-5B at week 4,and ACC and CPT-1 at week 8.The results indicated enhanced antioxidant activities at week 8,as evidenced by reduced hepatic malondialdehyde(MDA)level and improved antioxidant enzymes activities in PM and Succinate groups(P<0.05).Supplementing with Prevotella or succinate can alter the cecal microbiota.Specifically,the abundance of Prevotella in the Succinate group was significantly higher than that in the other 4 groups at the family and genus levels(P<0.05).Conclusions Oral intake of Prevotella and dietary supplementation of succinate can ameliorate lipid metabolism of laying hens.The beneficial effect of Prevotella is consistent across different species.The finding highlights that succinate,the primary metabolite of Prevotella,represents a more feasible feed additive for alleviating fatty liver in laying hens. 展开更多
关键词 Fatty liver Gut microbiota Laying hen PREVOTELLA SUCCINATE
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Rosemary extract improves egg quality by altering gut barrier function,intestinal microbiota and oviductal gene expressions in late-phase laying hens
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作者 Lianhua Zhang Junwei Ge +7 位作者 Fei Gao Min Yang Hui Li Fei Xia Hongtong Bai Xiangshu Piao Zhiying Sun Lei Shi 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期295-312,共18页
Background Rosemary extract(RE)has been reported to exert antioxidant property.However,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not be... Background Rosemary extract(RE)has been reported to exert antioxidant property.However,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not been systematically studied.This study was investigated to detect the potential effects of RE on performance,egg quality,serum parameters,intestinal heath,cecal microbiota and metabolism,and oviductal gene expressions in late-phase laying hens.A total of 21065-week-old“Jing Tint 6”laying hens were randomly allocated into five treatments with six replicates and seven birds per replicate and fed basal diet(CON)or basal diet supplemented with chlortetracycline at 50 mg/kg(CTC)or RE at 50 mg/kg(RE50),100 mg/kg(RE100),and 200 mg/kg(RE200).Results Our results showed that RE200 improved(P<0.05)Haugh unit and n-6/n-3 of egg yolk,serum superoxide dismutase(SOD)compared with CON.No significant differences were observed for Haugh unit and n-6/n-3 of egg yolk among CTC,RE50,RE100 and RE200 groups.Compared with CTC and RE50 groups,RE200 increased serum SOD activity on d 28 and 56.Compared with CON,RE supplementation decreased(P<0.05)total cholesterol(TC)level.CTC,RE100 and RE200 decreased(P<0.05)serum interleukin-6(IL-6)content compared with CON.CTC and RE200 increased jejunal m RNA expression of ZO-1 and Occludin compared with CON.The biomarkers of cecal microbiota and metabolite induced by RE 200,including Firmicutes,Eisenbergiella,Paraprevotella,Papillibacter,and butyrate,were closely associated with Haugh unit,n-6/n-3,SOD,IL-6,and TC.PICRUSt2 analysis indicated that RE altered carbohydrate and amino acid metabolism of cecal microbiota and increased butyrate synthesizing enzymes,including 3-oxoacid Co A-transferase and butyrate-acetoacetate Co A-transferase.Moreover,transcriptomic analysis revealed that RE200 improved gene expressions and functional pathways related to immunity and albumen formation in the oviductal magnum.Conclusions Dietary supplementation with 200 mg/kg RE could increase egg quality of late-phase laying hens via modulating intestinal barrier,cecal microbiota and metabolism,and oviductal function.Overall,RE could be used as a promising feed additive to improve egg quality of laying hens at late stage of production. 展开更多
关键词 Intestinal health Laying hens MICROBIOTA Oviductal function PHYTOCHEMICALS Production
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Hepatic steatosis is associated with dysregulated cholesterol metabolism and altered protein acetylation dynamics in chickens
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作者 Xiaoli Guo Qianqian Zhou +5 位作者 Jiaming Jin Fangren Lan Chaoliang Wen Junying Li Ning Yang Congjiao Sun 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期53-67,共15页
Background Hepatic steatosis is a prevalent manifestation of fatty liver, that has detrimental effect on the health and productivity of laying hens, resulting in economic losses to the poultry industry. Here, we aimed... Background Hepatic steatosis is a prevalent manifestation of fatty liver, that has detrimental effect on the health and productivity of laying hens, resulting in economic losses to the poultry industry. Here, we aimed to systematically investigate the genetic regulatory mechanisms of hepatic steatosis in laying hens.Methods Ninety individuals with the most prominent characteristics were selected from 686 laying hens according to the accumulation of lipid droplets in the liver, and were graded into three groups, including the control, mild hepatic steatosis and severe hepatic steatosis groups. A combination of transcriptome, proteome, acetylome and lipidome analyses, along with bioinformatics analysis were used to screen the key biological processes, modifications and lipids associated with hepatic steatosis.Results The rationality of the hepatic steatosis grouping was verified through liver biochemical assays and RNA-seq. Hepatic steatosis was characterized by increased lipid deposition and multiple metabolic abnormalities. Integration of proteome and acetylome revealed that differentially expressed proteins(DEPs) interacted with differentially acetylated proteins(DAPs) and were involved in maintaining the metabolic balance in the liver. Acetylation alterations mainly occurred in the progression from mild to severe hepatic steatosis, i.e., the enzymes in the fatty acid oxidation and bile acid synthesis pathways were significantly less acetylated in severe hepatic steatosis group than that in mild group(P < 0.05). Lipidomics detected a variety of sphingolipids(SPs) and glycerophospholipids(GPs) were negatively correlated with hepatic steatosis(r ≤-0.5, P < 0.05). Furthermore, the severity of hepatic steatosis was associated with a decrease in cholesterol and bile acid synthesis and an increase in exogenous cholesterol transport.Conclusions In addition to acquiring a global and thorough picture of hepatic steatosis in laying hens, we were able to reveal the role of acetylation in hepatic steatosis and depict the changes in hepatic cholesterol metabolism. The findings provides a wealth of information to facilitate a deeper understanding of the pathophysiology of fatty liver and contributes to the development of therapeutic strategies. 展开更多
关键词 ACETYLATION Cholesterol metabolism Hepatic steatosis Laying hens Multiomics
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Effect of dietary supplementation with discardednutrient medium of Cordyceps militaris on layingperformance and diversity of intestinal flora in laying hens
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作者 XU Fangxu ZHANG Jinying +2 位作者 LI Bingxin LIU Yefei WANG Ze 《沈阳师范大学学报(自然科学版)》 CAS 2024年第2期186-192,共7页
The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordy... The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordyceps militaris were added to the basal diet of laying hens. The results showed that the optimal addition of discarded nutrient medium of Cordyceps militaris in the diet of laying hens was 10%. According to the results of measuring the conventional indicators of eggs, the weight of eggs produced by laying hens fed with discarded nutrient medium of Cordyceps militaris was higher than that of laying hens fed with ordinary laying hens. The content of interleukin-1(IL-1) in the experimental group was significantly higher than that in the control group, and the concentration of IL-1 increased by 141.5 pg/mL, which indicated that the application of discarded nutrient medium of Cordyceps militaris effectively improved the immunity of laying hens. The high-throughput analysis of the intestinal contents of the two groups of laying hens showed that the microbial population abundance of the intestinal tract of the experimental group was greater than that of control group, and the application of discarded nutrient medium of Cordyceps militaris increased the diversity of bacteria in the intestinal tract of laying hens. In addition, the sensitivity of some pathogenic bacteria in the intestinal tract of chickens to drugs was also increased, thereby reducing the use of antibiotics. The secondary utilization of discarded nutrient medium of Cordyceps militaris has great development and utilization prospects, which provided a scientific reference and basic theoretical basis for the development of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 展开更多
关键词 Cordyceps militaris discarded nutrient medium drug susceptibility intestinal flora laying hens
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Effects of Abrus cantoniensis Hance Extract on Blood Lipid of Laying Hen Feed with High Energy and Low Protein Diet
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作者 Hailong LIU Jing CUI +4 位作者 Lingling WANG Fei WANG Xinghua ZHAO Ning MA Yan ZHANG 《Medicinal Plant》 2024年第5期96-99,共4页
[Objectives]To explore the effects of Abrus cantoniensis Hance(ACH)extract on blood lipid indicators of laying hen fed with high energy and low protein diet.[Methods]Sixty 90-day-old laying hens were randomly divided ... [Objectives]To explore the effects of Abrus cantoniensis Hance(ACH)extract on blood lipid indicators of laying hen fed with high energy and low protein diet.[Methods]Sixty 90-day-old laying hens were randomly divided into five groups:the blank control group(basic diet),the model group(high-energy and low-protein diet,HELPD),the low-dose group(HELPD+0.5 g ACH extract per hen,LACH),and the medium-dose group(HELPD+1 g ACH extract per hen,MACH),high dose group(HELPD+2 g ACH extract per hen,HACH).The ACH extract was administrated by drinking water for 48 d.[Results]Different doses of ACH could improve the pathological changes induced by high energy and low protein.ACH extract had no significant effect on blood routine indicators of laying hens(P>0.05).The contents of total cholesterol(TC),triglyceride(TG)and low density lipoprotein cholesterol(LDL-C)in the model group were significant-ly higher than those in the control group(P<0.05),while the content of high density lipoprotein cholesterol(HDL-C)was significantly lower than that in the control group(P<0.05).There was no significant difference in blood lipid between LACH group and model group(P>0.05).In MACH and HACH groups,the contents of TC,TG and LDL-C were significantly lower than those in the model group(P<0.05),and the content of HDL-C was significantly higher than that in the model group(P<0.05).[Conclusions]The ACH extract can regulate theHELPD-induced dyslipidemia in laying hens. 展开更多
关键词 Abrus cantoniensis Hance(ACH) High-energy and low-protein diet(HELPD) Laying hen LIPID
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Exploration on the Optimization Strategy for the Layup of Composite Material Pressure Vessels Based on Advanced Algorithms
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作者 Qingshan Zeng Zuxin Chen 《Open Journal of Applied Sciences》 2024年第9期2482-2505,共24页
This study aims to explore the influence of the laying angle on the pressure shell structure made of composite materials under the condition of a fixed shape. By using a composite material composed of a mixture of T80... This study aims to explore the influence of the laying angle on the pressure shell structure made of composite materials under the condition of a fixed shape. By using a composite material composed of a mixture of T800 carbon fiber and AG80 epoxy resin to design pressure vessels, this material combination can significantly improve the interlaminar shear strength and heat resistance. The article elaborates on the basic concepts and failure criteria of composite materials, such as the maximum stress criterion, the maximum strain criterion, the Tsai-Hill criterion, etc. With the help of the APDL parametric modeling language, the arc-shaped, parabolic, elliptical, and fitting curve-shaped pressure vessel models are accurately constructed, and the material property settings and mesh division are completed. Subsequently, APDL is used for static analysis, and the genetic algorithm toolbox built into Matlab is combined to carry out optimization calculations to determine the optimal laying angle. The research results show that the equivalent stress corresponding to the optimal laying angle of the arc-shaped pressure vessel is 5.3685e+08 Pa, the elliptical one is 5.1969e+08 Pa, the parabolic one is 5.8692e+08 Pa, and the fitting curve-shaped one is 5.36862e+08 Pa. Among them, the stress distribution of the fitting curve-shaped pressure vessel is relatively more uniform, with a deformation of 0.568E−03 m, a minimum equivalent stress value of 0.261E+09 Pa, a maximum equivalent stress value of 0.537E+09 Pa, and a ratio of 0.48, which conforms to the equivalent stress criterion. In addition, the fitting curve of this model can adapt to various models and has higher practical value. However, the stress distribution of the elliptical and parabolic pressure vessels is uneven, and their applicability is poor. In the future, further exploration can be conducted on the application of the fitting curve model in composite materials to optimize the design of pressure vessels. This study provides important theoretical support and practical guidance for the design of composite material pressure vessels. 展开更多
关键词 Composite Material Pressure Vessel Matlab APDL Parametric Modeling Static Analysis Optimal Laying Angle
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LaY沸石中La离子定位的研究 被引量:12
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作者 潘晖华 何鸣元 +2 位作者 宋家庆 田辉平 朱玉霞 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2007年第3期87-91,共5页
由二交二焙工艺及液-固工艺制备LaY沸石,采用多晶XRD结合Rietveld结构精修确定了La离子在Y沸石骨架外的分布。结果表明,进入方钠石笼的La离子定位于SⅠ’位置,与骨架O3形成配位,从而稳定沸石骨架,提高沸石水热稳定性。采用液-固工艺制备... 由二交二焙工艺及液-固工艺制备LaY沸石,采用多晶XRD结合Rietveld结构精修确定了La离子在Y沸石骨架外的分布。结果表明,进入方钠石笼的La离子定位于SⅠ’位置,与骨架O3形成配位,从而稳定沸石骨架,提高沸石水热稳定性。采用液-固工艺制备的LaY沸石中La离子与O3的距离比采用二交二焙工艺制备的LaY沸石中La离子与O3的距离要短。因此,前者La离子与O3的作用更强。采用液-固工艺制备的LaY沸石中,每个La离子除与3个O3配位外,还与2个羟基配位,La离子以[La(OH)2]+形式存在。2种工艺制备的样品中,均有少量Na+定位于六方柱笼SⅠ位置。采用二交二焙工艺制备的LaY沸石中,沸石骨架有轻微脱Al,有少量Al3+定位于SⅡ’位置。 展开更多
关键词 LaY沸石 稀土 结构精修 稀土离子位置
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柔性管Reel-lay铺管安装稳定性分析 被引量:6
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作者 白勇 唐继蔚 +2 位作者 余彬彬 阮伟东 闫会宾 《海洋工程》 CSCD 北大核心 2013年第6期22-29,共8页
钢管的S-lay、J-lay铺管方法的应用研究已经非常深入,而柔性管的Reel-lay铺管法的应用研究则相对较少。由于管道本身的材料非线性、管土接触存在非线性以及环境的不确定性等问题过于复杂,因此通过类比J-lay铺管法,采用整管的力学性能、... 钢管的S-lay、J-lay铺管方法的应用研究已经非常深入,而柔性管的Reel-lay铺管法的应用研究则相对较少。由于管道本身的材料非线性、管土接触存在非线性以及环境的不确定性等问题过于复杂,因此通过类比J-lay铺管法,采用整管的力学性能、弹性海底模型及均匀流等方式对Reel-lay铺管的水下段稳定性问题进行了简化;根据悬链线理论和小变形梁理论,给出了柔性管Reel-lay铺管法的数值计算方法,并与有限元模拟的结果进行了对比分析。结果表明:随着铺设角度增大,管道受到的弯矩也随之增大,但管道顶部的拉力却随之减小;随着铺设水深的增加,管道悬浮段质量增加,管道顶部拉力明显增加,但弯矩明显减小;浮重对管道铺设很重要,应根据实际情况,选择合适的配重以满足管道稳定和铺设的要求。 展开更多
关键词 柔性管 Reel—lay铺管法 整体稳定性 理论模型 有限元模型
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乌拉尔图小麦(Triticumurartu)lAy高分子量麦谷蛋白亚基基因编码区的克隆与鉴定 被引量:5
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作者 白建荣 贾旭 +1 位作者 刘坤凡 王道文 《Acta Botanica Sinica》 CSCD 2004年第4期463-471,共9页
应用简并性引物和基因组PCR反应从乌拉尔图小麦(Triticumurartu)不同种质材料中获得并测定了表达型和沉默型lAy高分子量麦谷蛋白亚基基因全长编码区的基因组DNA序列。表达型lAy基因编码区的序列与前人已发表的y型高分子量麦谷蛋白亚基... 应用简并性引物和基因组PCR反应从乌拉尔图小麦(Triticumurartu)不同种质材料中获得并测定了表达型和沉默型lAy高分子量麦谷蛋白亚基基因全长编码区的基因组DNA序列。表达型lAy基因编码区的序列与前人已发表的y型高分子量麦谷蛋白亚基基因编码区的序列高度同源,由其推导的lAy亚基的一级结构与已知的高分子量麦谷蛋白亚基相似。在细菌细胞中,表达型lAy基因编码区的克隆序列可经诱导而产生lAy蛋白,该蛋白与种子中lAy亚基在电泳迁移率和抗原性上类似,表明所克隆的序列真实地代表了表达型lAy基因的全长编码区。但是,本研究所克隆的沉默型lAy基因的编码区序列因含有3个提前终止子而不能翻译成完整的lAy蛋白。讨论了表达型lAy基因在小麦籽粒加工品质改良中的潜在利用价值以及lAy基因沉默的机制。 展开更多
关键词 乌拉尔图小麦 普通小麦 LAY 高分子量麦谷蛋白亚基 籽粒加工 品质改良 克隆 鉴定
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微波辅助均相沉淀法制备(Y_(1-x-y),La_y)_2O_3∶xEu^(3+)红色荧光粉 被引量:2
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作者 曾青云 李青 +2 位作者 肖婷 王宗俊 肖培南 《有色金属科学与工程》 CAS 2017年第2期107-111,共5页
用微波辅助均相沉淀法制备了一系列(Y_(1-x-y),La_y)_2O_3∶xEu^(3+)(x=0.01~0.05,y=0.05~0.25)红色荧光粉.研究Eu^(3+)、La^(3+)的掺杂浓度和煅烧温度对荧光粉性能的影响.通过差热分析仪、红外光谱仪、XRD、SEM和荧光分光光度计,对前... 用微波辅助均相沉淀法制备了一系列(Y_(1-x-y),La_y)_2O_3∶xEu^(3+)(x=0.01~0.05,y=0.05~0.25)红色荧光粉.研究Eu^(3+)、La^(3+)的掺杂浓度和煅烧温度对荧光粉性能的影响.通过差热分析仪、红外光谱仪、XRD、SEM和荧光分光光度计,对前驱体热重曲线和FTIR曲线、样品的晶体结构、表面形貌及颗粒大小和荧光性能进行表征.结果表明:前驱体组成为(Y,La,Eu)OHCO_3·nH_2O;所制备样品为立方晶系;SEM显示荧光粉为均匀分散的球形颗粒,粒度为200 nm左右;较为适宜的焙烧温度为900℃;La^(3+)掺杂含量y=10%,Eu^(3+)掺杂含量x=3%时,样品荧光粉发光性能最好,最大发射波长为614 nm,对应的是Eu^(3+)的5D0→7F2跃迁;样品的色坐标为(0.654,0.346).所制备的(Y_(1-x-y),La_y)_2O_3∶xEu^(3+)荧光粉具备较好的发光强度与色纯度. 展开更多
关键词 (Y1-x-y Lay)2O3∶xEu3+ 微波 红色荧光粉 均相沉淀法
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La交换NaY分子筛中的离子定位和迁移规律 被引量:14
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作者 杜晓辉 张海涛 +3 位作者 李雪礼 谭争国 刘宏海 高雄厚 《催化学报》 SCIE EI CAS CSCD 北大核心 2013年第8期1599-1607,共9页
以NaY分子筛为原料, 采用二次交换二次焙烧工艺, 制得了LaNH4Y-1, LaY-1, LaNH4Y-2和LaY-2四种分子筛样品. 采用粉末X射线衍射结合Rietveld结构精修确定了La离子在分子筛中的分布. 结果表明, 在离子交换过程中, La离子首先定位于分子筛... 以NaY分子筛为原料, 采用二次交换二次焙烧工艺, 制得了LaNH4Y-1, LaY-1, LaNH4Y-2和LaY-2四种分子筛样品. 采用粉末X射线衍射结合Rietveld结构精修确定了La离子在分子筛中的分布. 结果表明, 在离子交换过程中, La离子首先定位于分子筛超笼里; 经焙烧脱水后, La离子迁移到分子筛方钠石笼并定位在SI′位置. T-O-T键角的变化表明, LaNH4Y-1表现出最大的骨架扭曲性和结构不稳定性. La离子定位在SI′位置与O3配位, 增加了T-O3的键长, 表明稀土离子不仅通过控制骨架脱铝抑制晶胞收缩, 还可能通过影响T-O3键长使晶胞增大. 在REY分子筛中, 稀土的主要作用是稳定分子筛结构, 从而调节其酸性和催化活性. 采用红外光谱和NH3程序升温脱附考察了La离子和NH4+对分子筛酸性的影响, 并总结了稀土离子稳定Y型分子筛的机理. 展开更多
关键词 LaY型分子筛 RIETVELD结构精修 镧离子迁移 骨架结构 热稳定性
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海底管道S-Lay铺设过程中的质量控制 被引量:3
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作者 焦冬梅 于文太 +1 位作者 杜永军 韩旭 《中国海洋平台》 2013年第3期23-26,共4页
海底管道作为最主要的海洋石油天然气的运输方式,对施工质量要求很高。在对S-Lay铺管船铺设海底管道的铺管工艺进行介绍的基础上,利用因果分析法,对铺管过程中的潜在风险因素进行了识别和分析,并针对这些问题,对铺管过程中各个环节的质... 海底管道作为最主要的海洋石油天然气的运输方式,对施工质量要求很高。在对S-Lay铺管船铺设海底管道的铺管工艺进行介绍的基础上,利用因果分析法,对铺管过程中的潜在风险因素进行了识别和分析,并针对这些问题,对铺管过程中各个环节的质量控制要点进行了阐述,对类似项目的质量管理有参考意义。 展开更多
关键词 海底管道 S—Lay铺管 因果分析 质量控制
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Correlation between Polymorphism of Neuropeptide Y Gene and Traits at First Laying of Wenchang Chicken
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作者 朱文奇 李慧芳 +5 位作者 吴蓉蓉 宋卫涛 徐文娟 于吉英 肖小君 陈宽维 《Animal Husbandry and Feed Science》 CAS 2009年第2期5-7,12,共4页
[ Objective] The paper presents the polymorphism of neuropeptide Y gene (NPY) and its relationship with traits at first laying in Wen- chang chicken in order to provide information for breeding of high-yielding Wenc... [ Objective] The paper presents the polymorphism of neuropeptide Y gene (NPY) and its relationship with traits at first laying in Wen- chang chicken in order to provide information for breeding of high-yielding Wenchang chicken. [Method] The polymorphism of NPYgene at Dra I site was detected by PCR-RFLP, and the genotypes and the genetic stability were determined. The correlation between the polymorphism and traits at first laying (age, body weight and egg weight) was also analyzed. [Result] There were three kinds of genotype of NPYgene at Dra I site in Wenchang chicken, designated as AA, AB and BB; the distribution of these genotypes was consistent with the Hardy -Weinberg law; age and egg weight were not significantly different among the three genotypes ( P 〉0.05), and body weight was extremely significantly different ( P 〈0.01 ). [ Conclusion] The NPYgene of Wenchang chicken is in Hardy -Weinberg equilibrium at Dra I site, and its genetic polymorphism affects body weight at first laying. 展开更多
关键词 Wenchang chicken NPY gene Traits at first laying
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