Freilandversuche über Stickstoffumsetzungen und Aziditätsänderungen in verwesender Waldstreu     

Dr. Yellow Hwang 《European Journal of Forest Research》1938,60(21):661-676

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颗粒剂防治玉米钻心虫的研究     

郑炳宗  黄书针 《植物保护学报》1965,4(2):133-142

1962年在北京夏玉米上用顆粒剂防治玉米钻心虫的結果表明:心叶末期施5％DDT顆粒剂,防治一次,每株2克,在一般年份,从产量上来看是很有利的。同时对药剂残效,幼虫在玉米不同生育期植株上的分布,以及顆粒剂在心叶期施药至抽雄后在植株上的分布测定,并結合顆粒剂小区防治試驗。分析結果说明:心叶末期施药,影响药效的主要原因,不是5％DDT残效的問題,而是抽雄后药剂在植株上部分布較少,尤其是包在雄穗节外的第一叶腋没有药,而此时期,幼虫在植株上部分布較多,同时DDT速效也不如666。  相似文献   

Effects of Confluent, Roscovitine Treatment and Serum Starvation on the Cell-cycle Synchronization of Bovine Foetal Fibroblasts     

SR Cho  SA Ock  JG Yoo  B Mohana kumar  SY Choe  GJ Rho 《Reproduction in domestic animals》2005,40(2):171-176

The present study was designed to examine the effects of cell-cycle synchronization protocols, such as confluent, roscovitine treatment and serum starvation, in bovine foetal fibroblasts on synchronization accuracy at G0/G1, viability, apoptosis, necrosis and ploidy for use as a nuclei donor. The cells in 5-10 passages were randomly allocated into three treated groups. Cells were cultured either in Dulbecco's modified Eagle's medium (DMEM) + 10% foetal bovine serum (FBS) until 90% confluent (group 1, confluent), in DMEM + 10% FBS + 30 microM roscovitine for 12 h (group 2, roscovitine), or in DMEM + 0.5% FBS for 5 days (group 3, serum starvation). Most of the cells (>80%) in all groups were arrested at the G0/G1 stage. Although the rates did not differ, cells in group 1 showed an increased cell population arrested at the G0/G1 phase. Significantly (p < 0.05) higher rates of apoptosis occurred in group 3 than in group 1 and 2 (10% vs 6% and 6%, respectively). No differences in chromosomal abnormality were observed among groups. However, by increasing the number of cell culture passages up to 15, significantly (p < 0.05) higher chromosomal abnormality was observed than in 5 and 10 passages (39% vs 28% and 23%, respectively) in group 1. The results clearly indicated that bovine foetal fibroblasts could be effectively synchronized at G0/G1 stages by all the three different treatments, confluent, roscovitine and serum starvation. However, cells in confluent showed reduced apoptosis and necrosis when they underwent 5-10 passages, exhibiting increased percentage of cells with stable chromosome diversity. Hence, cells in confluent merit further studies before they could be used as nuclear donors.  相似文献   

Effects of surgical implantation of temperature dataloggers on reproduction of captive striped skunks (Mephitis mephitis).     

Yeen Ten Hwang  Marie-Line Gentes  Dennilyn L Parker  Serge Larivière  Fran?ois Messier 《Journal of zoo and wildlife medicine》2004,35(4):515-519

A total of 20 (14 females, six males) captive striped skunks (Mephitis mephitis) with miniature temperature dataloggers implanted free in the abdominal cavity were examined for reproductive performance and pathology because of implants. Eleven of 12 female skunks reproduced successfully 45.9+/-3.7 days after surgery to remove implanted dataloggers. The pregnancy rate of 91.7% (11/12) was much higher than other captive studies and was comparable with that of wild skunks. Eight striped skunks (six males, two females) that were euthanatized and necropsied after having implants in the abdominal cavity for 5 mo showed no apparent pathology associated with the implant. Implantation of the intraperitoneal devices did not lead to complications in abdominal tissues. Neither implant nor surgery affected reproduction. We conclude that implanted dataloggers can safely be used in physiologic studies of striped skunks or possibly other small carnivores in captive or field studies.  相似文献   

Differences in the growth stages of Erysiphe pisi on cultivars of field pea (Pisum sativum L.)     

Su  H.  Hwang  S. F.  Chang  K. F.  Conner  R. L.  Howard  R. J.  Turbull  G. D.  Blade  S. F. 《植物病害和植物保护杂志》2004,111(1):64-70

Journal of Plant Diseases and Protection - The infection process of Erysiphe pisi on field pea cvs. ‘Highlight’ and ‘Tara’ carrying resistance gene erl, line...  相似文献   

Novel Caryophyllane-Related Sesquiterpenoids with Anti-Inflammatory Activity from Rumphella antipathes (Linnaeus, 1758)     

Yu-Chia Chang  Chih-Chao Chiang  Yuan-Shiun Chang  Jih-Jung Chen  Wei-Hsien Wang  Lee-Shing Fang  Hsu-Ming Chung  Tsong-Long Hwang  Ping-Jyun Sung 《Marine drugs》2020,18(11)

Two previously undescribed caryophyllane-related sesquiterpenoids, antipacids A (1) and B (2), with a novel bicyclo[5.2.0] core skeleton, and known compound clovane-2β,9α-diol (3), along with rumphellolide L (4), an esterified product of 1 and 3, were isolated from the organic extract of octocoral Rumphella antipathes. Their structures, including the absolute configurations were elucidated by spectroscopic and chemical experiments. In vivo anti-inflammatory activity analysis indicated that antipacid B (2) inhibited the generation of superoxide anions and the release of elastase by human neutrophils, with IC₅₀ values of 11.22 and 23.53 μM, respectively, while rumphellolide L (4) suppressed the release of elastase with an IC₅₀ value of 7.63 μM.  相似文献   

Directly-prelithiated carbon nanotube film for high-performance flexible lithium-ion battery electrodes     

Sehyun Lee  Hyeonjun Song  Jun Yeon Hwang  Youngjin Jeong 《Fibers and Polymers》2017,18(12):2334-2341

Carbon nanotube (CNT) films are very flexible and serve as active materials for lithium-ion batteries (LIBs). Hence, they have high potential as flexible free-standing electrodes for wearable batteries. However, nanocarbon materials such as CNTs and graphene are of limited use as electrodes because they have a large initial irreversible capacity due to the formation of a solid electrolyte interphase (SEI). Herein, we prelithiated the CNT films to make them available as electrodes for flexible batteries by reducing their irreversible capacity. The SEI is pre-formed through a direct prelithiation (DP) method that brings lithium metal into direct contact with CNT films in an electrolyte. As a result, the capacity of directly-prelithiated CNT film electrodes continues to increase to 1520 mAh/g until 350th cycle of charge/discharge and their initial irreversible capacity vanishes. The changes in the electrochemical properties of CNT film electrodes by DP treatment and their flexibility are investigated.  相似文献   

Evidence for functional G-coupled protein receptors 43 and 120 in subcutaneous and intramuscular adipose tissue of Angus crossbred steers     

Lindsay Westbrook  Bradley J Johnson  Gyoungok Gang  Kentaro Toyonaga  Jinhee Hwang  Kiyong Chung  Stephen B Smith 《Journal of animal science》2021,99(6)

We conducted 3 independent experiments to demonstrate functional G-coupled protein receptor 43 (GPR43) and GPR120 in bovine intramuscular (i.m.) and subcutaneous (s.c.) adipose tissues. We hypothesized that media volatile fatty acids and long-chain fatty acids would affect cAMP-activated protein kinase-alpha (AMPKα) protein expression and cAMP concentrations differently in i.m. and s.c. adipose tissue. Experiment 1: oleic acid (18:1n-9) decreased phosphorylated AMPKα protein (p-AMPKα) and the p-AMPKα/AMPKα protein ratio in i.m. preadipocytes, increased the p-AMPKα/AMPKα protein ratio in bovine satellite cells, and had no effect in s.c. preadipocytes. Experment 2: ex vivo explants from the 5th to 8th longissimus thoracic rib muscle section of Angus crossbred steers were cultured 48 hr in media containing 0.25 µM ciglitizone, 5 mM glucose, and 5 mM acetate, in the absence or the presence of 100 µM oleic acid. Oleic acid increased acetate incorporation into fatty acids and GPR43 gene expression in i.m. adipose tissue (P < 0.05), but oleic acid had no effect on fatty acid synthesis or GPR43 expression in s.c. adipose tissue. Experiment 3: fresh s.c. and i.m. adipose tissue from the 5th to 8th longissimus thoracic rib muscle section of Angus crossbred steers was transferred immediately to 6-well culture plates containing 3 mL of KHB/Hepes/5 mM glucose. Samples were preincubated with 0.5 mM theophylline plus 10 μM forskolin for 30 min, after which increasing concentrations of acetate or propionate (0, 10⁻³, 10^−2.3, and 10⁻³ M) in the absence or the presence of 100 μM oleic acid or 100 µM palmitic acid (16:0) were added to the incubation media. Acetate had no effect on forskolin-stimulated cAMP production in s.c. adipose tissue but decreased cAMP in i.m. adipose tissue (P < 0.05); this indicates a functional GPR43 receptor in i.m. adipose tissue. The combination of 10⁻² M acetate and oleic acid decrease cAMP production in s.c. adipose tissue, consistent with GPR120 receptor activity, but oleic acid and palmitic acid attenuated the depression of cAMP production caused by acetate in i.m. adipose tissue. Palmitic acid depressed cAMP production in s.c. adipose tissue, and increased cAMP production in i.m. adipose tissue (P < 0.05). Propionate had no effect on cAMP production in s.c. or i.m. adipose tissue. These results provide evidence for functional GPR43 receptors in i.m. adipose tissue and GPR120 receptors in s.c. adipose tissue, both of which would suppress lipolysis.  相似文献   

Use of monoclonal antibodies to identify outer membrane antigens of Actinobacillus species     

M C Healey  H M Gharpure  S J Kleinschuster  H H Hwang  A V Johnston 《American journal of veterinary research》1986,47(7):1446-1451

Three monoclonal antibodies (LG17, LG30, and LG33) were used to identify outer membrane antigens of Actinobacillus sp (As8C isolate) cultured from the epididymides of an infected ram lamb. Specificity of the 3 antibodies to As8C antigens was determined by use of bacterial agglutination, the enzyme-linked immunosorbent assay, and the indirect fluorescent antibody test. Results of immunoelectron microscopy confirmed that each antibody was specific for epitopes on As8C outer membrane antigens. Evaluation by use of enzyme-linked immunoelectrotransfer blot indicated that target antigens for LG17 and LG33 antibodies had molecular weights of 10 kilodaltons and 43 kilodaltons, respectively. Multiple-band staining was observed with the LG33 antibody. The target antigen for the LG30 antibody could not be discerned by use of enzyme-linked immunoelectrotransfer blot. For each of the 3 monoclonal antibodies, enzyme-linked immunosorbent assay titers were obtained for Actinobacillus seminis, A actinomycetemcomitans, and 10 field isolates of Actinobacillus spp. Target antigens for LG17 and LG30 antibodies occurred infrequently or were absent on these bacteria. However, the target antigen for the LG33 antibody was shared by Actinobacillus seminis, A actinomycetemcomitans, and the 10 field isolates of Actinobacillus spp, indicating some diversity of outer membrane antigens between isolates.  相似文献   

Improved monospermic fertilization and subsequent blastocyst formation of bovine oocytes fertilized in vitro in a medium containing NaCl of decreased concentration     

Roh S  Hwang W  Lee B  Lim J  Lee E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(8):667-671

The objective of this study was to evaluate whether changes in NaCl concentration in a fertilization medium could improve normal fertilization and preimplantation development of bovine oocytes. In vitro matured bovine oocytes were inseminated with frozen-thawed semen for 18 hr in a Tyrode's medium with albumin, lactate and pyruvate (TALP), to which 114 (TALP-114), 96 (TALP-96) or 78 (TALP-78) mM NaCl was added. Presumptive zygotes were cultured for 192 hr in a modified TALP containing 90 mM NaCl, 1.5 mM glucose, 0.3% (w/v) BSA, minimal essential medium (MEM) essential and nonessential amino acids, and insulin-transferrin-selenium complex. Lower polyspermy rate was obtained by the insemination in TALP-96 (7.8 +/- 2.3%) than by the insemination in TALP-114 (25.6 +/- 1.4%), without decrease in male pronucleus (MPN) formation. Fertilization in TALP-78 also yielded decreased polyspermic fertilization (3.8 +/- 1.5%), but significant decrease in MPN formation was found (63.1 +/- 3.1%). In preimplantation development, more blastocysts developed from oocytes inseminated in TALP-96 (24.1 +/- 1.7%) than from oocytes inseminated in TALP-114 (16.8 +/- 1.4%). TALP-78, however, did not improve preimplantation development beyond the 8-cell stage compared with TALP-114. Mean cell number of blastocyst was higher when oocytes were fertilized in TALP-96 (137.0 +/- 4.5) than in TALP-114 (123.1 +/- 5.1) and in TALP-78 (102.3 +/- 4.5). These results demonstrate that insemination of bovine oocytes in a TALP with decreased NaCl concentration (96 mM) improves blastocyst formation and embryo viability. Decrease in NaCl concentration below 96 mM, however, may delay or inhibit MPN formation, and inhibits subsequent development in vitro.  相似文献