Pigs experience biological stress such as physiological, environmental, and social challenges when weaned from the sow. The process of weaning is one of the most stressful events in the pig＇s life that can contribute...Pigs experience biological stress such as physiological, environmental, and social challenges when weaned from the sow. The process of weaning is one of the most stressful events in the pig＇s life that can contribute to intestinal and immune system dysfunctions that result in reduced pig health, growth, and feed intake, particularly during the first week after weaning. Technological improvements in housing, nutrition, health, and management have been used to minimize some of the adverse effects of weaning stress, but a greater understanding of the biological impact of stress is needed to improve strategies to overcome weaning stress. The focus of this review paper is to briefly describe how the biological stress associated with weaning impacts intestinal morphology, structure, physiology, and intestinal immune responses that can impact subsequent production efficiencies such as growth, intake, morbidity, and mortality.展开更多
远距离跨区直流输电规模持续增长,使得电力系统暂态电压稳定（transient voltage stability,TVS）问题突出,量化评估暂态电压稳定裕度具有重要意义。针对现有实用暂态电压评估指标区分度低的问题,基于二元表描述,提出一种可用多二元表...远距离跨区直流输电规模持续增长,使得电力系统暂态电压稳定（transient voltage stability,TVS）问题突出,量化评估暂态电压稳定裕度具有重要意义。针对现有实用暂态电压评估指标区分度低的问题,基于二元表描述,提出一种可用多二元表描述的暂态电压稳定裕度指标。首先,介绍现有的实用暂态电压稳定判据及其衍生的暂态电压跌落可接受性（transient voltage dip acceptability,TVDA）指标。其次,介绍表征可接受性的单二元表判据和表征稳定裕度的单二元表判据,并从二元表判据角度分析比较现有暂态电压可接受性判据特性及其缺陷。再次,基于不同跌落程度权重不同的思想,提出基于多二元表的可接受性判据,并给出相关权重系数的计算方法;进而结合暂态电压稳定要求,提出暂态电压稳定裕度指标。最后,基于实际电网数据仿真验证基于多二元表的暂态电压稳定裕度指标具有对负荷水平、故障等运行条件更强的适用性和有效性。展开更多
Chronic inflammation is often associated with alcoholrelated medical conditions. The key inducer of such inflammation, and also the best understood, is gut microflora-derived lipopolysaccharide (LPS). Alcohol can sign...Chronic inflammation is often associated with alcoholrelated medical conditions. The key inducer of such inflammation, and also the best understood, is gut microflora-derived lipopolysaccharide (LPS). Alcohol can significantly increase the translocation of LPS from the gut. In healthy individuals, the adverse effects of LPS are kept in check by the actions and interactions of multiple organs. The liver plays a central role in detoxifying LPS and producing a balanced cytokine milieu. The central nervous system contributes to anti-inflammatory regulation through neuroimmunoendocrine actions. Chronic alcohol use impairs not only gut and liver functions, but also multi-organ interactions, leading to persistent systemic inflammation and ultimately, to organ damage. The study of these interactions may provide potential new targets for therapeutic intervention.展开更多
Insulinomas continue to pose a diagnostic challenge to physicians, surgeons and radiologists alike. Most are intrapancreatic, benign and solitary. Biochemical diagnosis is obtained and imaging techniques to localize l...Insulinomas continue to pose a diagnostic challenge to physicians, surgeons and radiologists alike. Most are intrapancreatic, benign and solitary. Biochemical diagnosis is obtained and imaging techniques to localize lesions continue to evolve. Surgical resection is the treatment of choice. Despite all efforts, an occult insulinoma (occult insulinoma refers to a biochemically proven tumor with indeterminate anatomical site before operation) may still be encountered. New localization preoperative techniques decreases occult cases and the knowledge of the site of the mass before surgery allows to determine whether enucleation of the tumor or pancreatic resection is likely to be required and whether the tumor is amenable to removal via a laparoscopic approach. In absence of preoperative localization and intraoperative detection of an insulinoma, blind pancreatic resection is not recommended.展开更多
为确定滴灌条件下温室黄瓜的适宜灌水方案,该文基于20 cm标准蒸发皿的累计水面蒸发量设计不同灌水处理,研究了滴灌条件下不同灌水处理(充分灌水T1,轻度水分亏缺T2,中度水分亏缺T3)对不同种植季节温室黄瓜生理特性、耗水量(Evapotranspir...为确定滴灌条件下温室黄瓜的适宜灌水方案,该文基于20 cm标准蒸发皿的累计水面蒸发量设计不同灌水处理,研究了滴灌条件下不同灌水处理(充分灌水T1,轻度水分亏缺T2,中度水分亏缺T3)对不同种植季节温室黄瓜生理特性、耗水量(Evapotranspiration,ET_c)、产量及水分利用效率(Water Use Efficiency,WUE)的影响,且于2017年8-12月(秋冬季)和2018年3-7月(春夏季)分别对不同灌水处理下土壤水分状况、作物生理指标、耗水量、产量和WUE等指标进行了系统的田间试验观测及分析。研究结果表明,随着灌水量的减小,温室黄瓜产量和WUE均呈降低趋势,不同程度的水分亏缺对黄瓜不同生育期ET_c有一定的抑制作用,在黄瓜生长任一阶段发生水分亏缺均会降低黄瓜植株的茎流速率、光合速率及气孔导度,进而可能影响黄瓜干物质的运转与积累,其中在作物生长中期,温室黄瓜茎流速率及产量对水分亏缺响应最为显著。黄瓜平均单果质量、果茎、果长和单株坐果数均随灌水量的降低而减小,黄瓜果实畸形比例随不同生长阶段水分亏缺的增大而增大。不同种植季节温室黄瓜T1处理的产量分别高出T2和T3处理的22.0%和51.2%(春夏季)、54.2%和73.9%(秋冬季);温室黄瓜T1处理的ET_c分别高出T2和T3处理的17.4%和34.9%(春夏季)、24.0%和48.0%(秋冬季);T1处理的WUE分别高出T2和T3处理的5.5%和25%(春夏季)、39.7%和50.0%(秋冬季)。综合研究结果,黄瓜发育期适宜灌溉水量为累计水面蒸发量的0.8倍,生长中、后期为累计水面蒸发量的1.2倍。研究结果对实现农业水分高效利用及促进设施作物优质、高产具有重要参考价值。展开更多
AIM： To estimate the prevalence and identify the risk factors for metabolic bone disease in patients with cirrhosis. METHODS： The study was performed on 72 Indian patients with cirrhosis （63 male, 9 female; aged 〈...AIM： To estimate the prevalence and identify the risk factors for metabolic bone disease in patients with cirrhosis. METHODS： The study was performed on 72 Indian patients with cirrhosis （63 male, 9 female; aged 〈 50 years）. Etiology of cirrhosis was alcoholism （n = 37）, hepatitis B （n = 25） and hepatitis C （n = 10）. Twenty-three patients belonged to Child class A, while 39 were in class B and 10 in class C. Secondary causes for metabolic bone disease and osteoporosis were ruled out. Sunlight exposure, physical activity and dietary constituents were calculated. Complete metabolic profiles were derived, and bone mineral density （BMD） was measured using dual energy X ray absorptiometry. Low BMD was defined as a Z score below -2. RESULTS： Low BMD was found in 68% of patients. Lumbar spine was the most frequently and severely affected site. Risk factors for low BMD included low physical activity, decreased sunlight exposure, and low lean body mass. Calcium intake was adequate, with unfavorable calcium： protein ratio and calcium： phosphorus ratio. Vitamin D deficiency was highly prevalent （92%）. There was a high incidence of hypogonadism （41%）. Serum estradiol level was elevated significantly in patients with normal BMD. Insulin-like growth factor （IGF） 1 and IGF binding protein 3 levels were below the age-related normal range in both groups. IGF-1 was significantly lower in patients with low BMD. Serum osteocalcin level was low （68%） and urinary deoxypyridinoline to creatinine ratio was high （79%）, which demonstrated low bone formation with high resorption. CONCLUSION： Patients with cirrhosis have low BMD. Contributory factors are reduced physical activity, low lean body mass, vitamin D deficiency and hypogonadism and low IGF-1 level.展开更多
When adipose-derived stem cells （ASCs） arc retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based...When adipose-derived stem cells （ASCs） arc retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based on their buoyancy, mature adipocytes can be easily isolated from the adipose cell suspension and dediffercn- tiated into lipid-frce fibroblast-like cells, named dediffercntiated fat （DFAT） cells. DFAT cells rc-establish active proliferation ability and undertake multipotent capacities. Compared with ASCs and other adult stem cells, DFAT cells showed unique advantages in their abundance, isolation and homogeneity. In this concise review, the establishment and culture methods of DFAT cells arc introduced and the current profiles of their cellular nature are summarized. Under proper inducti~,n culture in vitro or environment in vivo, DFAT cells could demonstrate adipogenic, osteogenic, chondrogenie and myogenic potentials. In angiogenie conditions, DFAT cells could exhibit perivascular characteristics antt elicit neovascularization. Our preliminary findings also suggested the pericyte phenotype underlying such cell lineage, which supported a novel interpretation about the common origin of mesenchymal stem cells and tissue-specific stem cells within blood vessel walls. Current research on DFAT cells indicated that this alternative source of adult multipotent cells has great potential in tissue engineering and regenerative medicine.展开更多
The manipulation and characterization of light polarization states are essential for many applications in quantum communication and computing,spectroscopy,bioinspired navigation,and imaging.Chiral metamaterials and me...The manipulation and characterization of light polarization states are essential for many applications in quantum communication and computing,spectroscopy,bioinspired navigation,and imaging.Chiral metamaterials and metasurfaces facilitate ultracompact devices for circularly polarized light generation,manipulation,and detection.Herein,we report bioinspired chiral metasurfaces with both strong chiral optical effects and low insertion loss.We experimentally demonstrated submicron-thick circularly polarized light filters with peak extinction ratios up to 35 and maximum transmission efficiencies close to 80% at near-infrared wavelengths(the best operational wavelengths can be engineered in the range of 1.3-1.6μm).We also monolithically integrated the microscale circular polarization filters with linear polarization filters to perform full-Stokes polarimetric measurements of light with arbitrary polarization states.With the advantages of easy on-chip integration,ultracompact footprints,scalability,and broad wavelength coverage,our designs hold great promise for facilitating chip-integrated polarimeters and polarimetric imaging systems for quantum-based optical computing and information processing,circular dichroism spectroscopy,biomedical diagnosis,and remote sensing applications.展开更多
文摘Pigs experience biological stress such as physiological, environmental, and social challenges when weaned from the sow. The process of weaning is one of the most stressful events in the pig＇s life that can contribute to intestinal and immune system dysfunctions that result in reduced pig health, growth, and feed intake, particularly during the first week after weaning. Technological improvements in housing, nutrition, health, and management have been used to minimize some of the adverse effects of weaning stress, but a greater understanding of the biological impact of stress is needed to improve strategies to overcome weaning stress. The focus of this review paper is to briefly describe how the biological stress associated with weaning impacts intestinal morphology, structure, physiology, and intestinal immune responses that can impact subsequent production efficiencies such as growth, intake, morbidity, and mortality.
文摘远距离跨区直流输电规模持续增长,使得电力系统暂态电压稳定（transient voltage stability,TVS）问题突出,量化评估暂态电压稳定裕度具有重要意义。针对现有实用暂态电压评估指标区分度低的问题,基于二元表描述,提出一种可用多二元表描述的暂态电压稳定裕度指标。首先,介绍现有的实用暂态电压稳定判据及其衍生的暂态电压跌落可接受性（transient voltage dip acceptability,TVDA）指标。其次,介绍表征可接受性的单二元表判据和表征稳定裕度的单二元表判据,并从二元表判据角度分析比较现有暂态电压可接受性判据特性及其缺陷。再次,基于不同跌落程度权重不同的思想,提出基于多二元表的可接受性判据,并给出相关权重系数的计算方法;进而结合暂态电压稳定要求,提出暂态电压稳定裕度指标。最后,基于实际电网数据仿真验证基于多二元表的暂态电压稳定裕度指标具有对负荷水平、故障等运行条件更强的适用性和有效性。
文摘Chronic inflammation is often associated with alcoholrelated medical conditions. The key inducer of such inflammation, and also the best understood, is gut microflora-derived lipopolysaccharide (LPS). Alcohol can significantly increase the translocation of LPS from the gut. In healthy individuals, the adverse effects of LPS are kept in check by the actions and interactions of multiple organs. The liver plays a central role in detoxifying LPS and producing a balanced cytokine milieu. The central nervous system contributes to anti-inflammatory regulation through neuroimmunoendocrine actions. Chronic alcohol use impairs not only gut and liver functions, but also multi-organ interactions, leading to persistent systemic inflammation and ultimately, to organ damage. The study of these interactions may provide potential new targets for therapeutic intervention.
文摘Insulinomas continue to pose a diagnostic challenge to physicians, surgeons and radiologists alike. Most are intrapancreatic, benign and solitary. Biochemical diagnosis is obtained and imaging techniques to localize lesions continue to evolve. Surgical resection is the treatment of choice. Despite all efforts, an occult insulinoma (occult insulinoma refers to a biochemically proven tumor with indeterminate anatomical site before operation) may still be encountered. New localization preoperative techniques decreases occult cases and the knowledge of the site of the mass before surgery allows to determine whether enucleation of the tumor or pancreatic resection is likely to be required and whether the tumor is amenable to removal via a laparoscopic approach. In absence of preoperative localization and intraoperative detection of an insulinoma, blind pancreatic resection is not recommended.
文摘为确定滴灌条件下温室黄瓜的适宜灌水方案,该文基于20 cm标准蒸发皿的累计水面蒸发量设计不同灌水处理,研究了滴灌条件下不同灌水处理(充分灌水T1,轻度水分亏缺T2,中度水分亏缺T3)对不同种植季节温室黄瓜生理特性、耗水量(Evapotranspiration,ET_c)、产量及水分利用效率(Water Use Efficiency,WUE)的影响,且于2017年8-12月(秋冬季)和2018年3-7月(春夏季)分别对不同灌水处理下土壤水分状况、作物生理指标、耗水量、产量和WUE等指标进行了系统的田间试验观测及分析。研究结果表明,随着灌水量的减小,温室黄瓜产量和WUE均呈降低趋势,不同程度的水分亏缺对黄瓜不同生育期ET_c有一定的抑制作用,在黄瓜生长任一阶段发生水分亏缺均会降低黄瓜植株的茎流速率、光合速率及气孔导度,进而可能影响黄瓜干物质的运转与积累,其中在作物生长中期,温室黄瓜茎流速率及产量对水分亏缺响应最为显著。黄瓜平均单果质量、果茎、果长和单株坐果数均随灌水量的降低而减小,黄瓜果实畸形比例随不同生长阶段水分亏缺的增大而增大。不同种植季节温室黄瓜T1处理的产量分别高出T2和T3处理的22.0%和51.2%(春夏季)、54.2%和73.9%(秋冬季);温室黄瓜T1处理的ET_c分别高出T2和T3处理的17.4%和34.9%(春夏季)、24.0%和48.0%(秋冬季);T1处理的WUE分别高出T2和T3处理的5.5%和25%(春夏季)、39.7%和50.0%(秋冬季)。综合研究结果,黄瓜发育期适宜灌溉水量为累计水面蒸发量的0.8倍,生长中、后期为累计水面蒸发量的1.2倍。研究结果对实现农业水分高效利用及促进设施作物优质、高产具有重要参考价值。
基金Supported by Corpus generated by Department of Endocrinology, KEM Hospital, Mumbai, India
文摘AIM： To estimate the prevalence and identify the risk factors for metabolic bone disease in patients with cirrhosis. METHODS： The study was performed on 72 Indian patients with cirrhosis （63 male, 9 female; aged 〈 50 years）. Etiology of cirrhosis was alcoholism （n = 37）, hepatitis B （n = 25） and hepatitis C （n = 10）. Twenty-three patients belonged to Child class A, while 39 were in class B and 10 in class C. Secondary causes for metabolic bone disease and osteoporosis were ruled out. Sunlight exposure, physical activity and dietary constituents were calculated. Complete metabolic profiles were derived, and bone mineral density （BMD） was measured using dual energy X ray absorptiometry. Low BMD was defined as a Z score below -2. RESULTS： Low BMD was found in 68% of patients. Lumbar spine was the most frequently and severely affected site. Risk factors for low BMD included low physical activity, decreased sunlight exposure, and low lean body mass. Calcium intake was adequate, with unfavorable calcium： protein ratio and calcium： phosphorus ratio. Vitamin D deficiency was highly prevalent （92%）. There was a high incidence of hypogonadism （41%）. Serum estradiol level was elevated significantly in patients with normal BMD. Insulin-like growth factor （IGF） 1 and IGF binding protein 3 levels were below the age-related normal range in both groups. IGF-1 was significantly lower in patients with low BMD. Serum osteocalcin level was low （68%） and urinary deoxypyridinoline to creatinine ratio was high （79%）, which demonstrated low bone formation with high resorption. CONCLUSION： Patients with cirrhosis have low BMD. Contributory factors are reduced physical activity, low lean body mass, vitamin D deficiency and hypogonadism and low IGF-1 level.
文摘When adipose-derived stem cells （ASCs） arc retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based on their buoyancy, mature adipocytes can be easily isolated from the adipose cell suspension and dediffercn- tiated into lipid-frce fibroblast-like cells, named dediffercntiated fat （DFAT） cells. DFAT cells rc-establish active proliferation ability and undertake multipotent capacities. Compared with ASCs and other adult stem cells, DFAT cells showed unique advantages in their abundance, isolation and homogeneity. In this concise review, the establishment and culture methods of DFAT cells arc introduced and the current profiles of their cellular nature are summarized. Under proper inducti~,n culture in vitro or environment in vivo, DFAT cells could demonstrate adipogenic, osteogenic, chondrogenie and myogenic potentials. In angiogenie conditions, DFAT cells could exhibit perivascular characteristics antt elicit neovascularization. Our preliminary findings also suggested the pericyte phenotype underlying such cell lineage, which supported a novel interpretation about the common origin of mesenchymal stem cells and tissue-specific stem cells within blood vessel walls. Current research on DFAT cells indicated that this alternative source of adult multipotent cells has great potential in tissue engineering and regenerative medicine.
基金supported in part by the AFOSR YIP under grant no.FA9550-16-1-0183the National Science Foundation under grant no.1809997+2 种基金partial support from the National Science Foundation under grant no.1711412Arizona State University startup funds provided to C.W.supported,in part,by NSF contract ECCS-1542160.
文摘The manipulation and characterization of light polarization states are essential for many applications in quantum communication and computing,spectroscopy,bioinspired navigation,and imaging.Chiral metamaterials and metasurfaces facilitate ultracompact devices for circularly polarized light generation,manipulation,and detection.Herein,we report bioinspired chiral metasurfaces with both strong chiral optical effects and low insertion loss.We experimentally demonstrated submicron-thick circularly polarized light filters with peak extinction ratios up to 35 and maximum transmission efficiencies close to 80% at near-infrared wavelengths(the best operational wavelengths can be engineered in the range of 1.3-1.6μm).We also monolithically integrated the microscale circular polarization filters with linear polarization filters to perform full-Stokes polarimetric measurements of light with arbitrary polarization states.With the advantages of easy on-chip integration,ultracompact footprints,scalability,and broad wavelength coverage,our designs hold great promise for facilitating chip-integrated polarimeters and polarimetric imaging systems for quantum-based optical computing and information processing,circular dichroism spectroscopy,biomedical diagnosis,and remote sensing applications.
