Increasing levels of pollution within water bodies can cause eutrophication and an associated rapid growth in and reproduction of phytoplankton. Although most frequently occurring in bodies of water such as lakes and ...Increasing levels of pollution within water bodies can cause eutrophication and an associated rapid growth in and reproduction of phytoplankton. Although most frequently occurring in bodies of water such as lakes and dams, in recent years an increasing number of river systems in China have suffered serious algal blooms. The community structure of phytoplankton may differ, however, dependent on the hydrodynamic conditions and nutrient levels within the water body. The field investigation results obtained from a stagnant river in Suzhou City and Taihu Lake, China, showed that in water with higher concentrations of nitrogen and phosphorus, Chlorophyta became the predominant species and in water with lower concentrations of nitrogen and phosphorus, Cyanobacteria became the predominant species. Growth experiments with competitive species, Microcystis aeruginosa Kutz and Scenedesmus quadricauda （Turp.）, were conducted at three different nutrient levels. The biomass of algae in pure and mixed cultures was measured under conditions of different N/P ratios at oligotrophic, eutrophic and hypertrophic nutrient levels. The results indicated that the most suitable state for the growth and reproduction of M. aeruginosa and S. quadricauda were eutrophic conditions in both pure and mixed cultures. Under competition, however, the lower medium nutrient levels favoured M. aeruginosa, while the higher medium nutrient levels better suited S. quadricauda. Under similar hydrodynamic conditions, the community structure of phytoplankton in the water body was determined by the dominant species in competition for nutrients.展开更多
Eleven barnyardgrass populations were assayed. The highest resistant population was Geqiushan R with RI 125.45 resulted from the seed assay and 87.29 resulted from the whole plant bioassay followed by 853 R with RI 2....Eleven barnyardgrass populations were assayed. The highest resistant population was Geqiushan R with RI 125.45 resulted from the seed assay and 87.29 resulted from the whole plant bioassay followed by 853 R with RI 2.79 resulted from the seed assay and 6.04 resulted from the whole plant bioassay. The resistance level of other nine populations was low with RI 1.13-2.61 resulted from the seed assay and 1.48-3.63 resulted from the whole plant bioassay. The activity of an important metabolic enzyme glutathione S-transferases （GSTs） and three protective enzymes （SOD, POD, and CAT） were determined in vivo for Geqiushan R, 853 R, and Wudalianchi R. Compared with the S controls, the activities of POD in Geqiushan R, GSTs in 853 R, and Wudalianchi R were increased.展开更多
[ Objective] To investigate the effects of different nutritional levels on production performance, apparent digestibility of nutrients and car- cass quality, and determine the optimal levels of energy, crude protein, ...[ Objective] To investigate the effects of different nutritional levels on production performance, apparent digestibility of nutrients and car- cass quality, and determine the optimal levels of energy, crude protein, calcium and phosphorus in diet for the Landrace pigs at fattening stage. [ Method] A total of 36 healthy Landrace pigs at the same parity with close weaning age and similar body weight [ （70 ± 1 ） kg ~ were selected. They were divided into nine experimental groups randomly. The experiment was carried out according to the L9 （3^4） orthogonal design. Then the production performance, apparent digestibility of nutrients and carcass quality were determined, respectively. The preliminary trial lasted for 7 d, and the trial lasted for 42 d. [ Result] The levels of crude protein and calcium had significant effects on the average daily gain （ P 〈 0.05）, and the energy level had extremely significant effects on the average daily gain （ P 〈 0.01 ）. The levels of energy, crude protein, calcium and phosphorus had effects on the apparent digestibility of nutrients in various degrees. The crude protein level had significant effects on the backfat P2 （P 〈 0.05） ; the energy level had significant effects on the backfat P2 and backfat P1 （P 〈 0.05） ; and the calcium level had significant effects on backfat P2 and lean meat percentage （P 〈 0.05）. [ Condasion] During the fattening period, the requirement of digestible energy, crude protein, calcium and phosphorus for the new America-line Landrace pills was 13.39 MJ/ka. 16.00%. 1.45% and 0.90%. respectively.展开更多
The influence of a deep-level-defect（DLD） band formed in a heavily Mg-doped GaN contact layer on the performance of Ni/Au contact to p-GaN is investigated. The thin heavily Mg-doped GaN（p^＋＋-GaN） contact layer w...The influence of a deep-level-defect（DLD） band formed in a heavily Mg-doped GaN contact layer on the performance of Ni/Au contact to p-GaN is investigated. The thin heavily Mg-doped GaN（p^＋＋-GaN） contact layer with DLD band can effectively improve the performance of Ni/Au ohmic contact to p-GaN. The temperature-dependent I–V measurement shows that the variable-range hopping（VRH） transportation through the DLD band plays a dominant role in the ohmic contact. The thickness and Mg/Ga flow ratio of p^＋＋-GaN contact layer have a significant effect on ohmic contact by controlling the Mg impurity doping and the formation of a proper DLD band. When the thickness of the p^＋＋-GaN contact layer is 25 nm thick and the Mg/Ga flow rate ratio is 10.29%, an ohmic contact with low specific contact resistivity of 6.97×10^-4Ω·cm^2 is achieved.展开更多
目的:在高孕激素超促排卵(progestin-primed ovarian stimulation,PPOS)及全胚胎冷冻移植的背景下,探讨诱发排卵日内源性孕酮(P)水平与多囊卵巢综合征(polycystic ovary syndrome,PCOS)患者体外受精/卵胞质内单精子显微注射(IVF/ICSI)...目的:在高孕激素超促排卵(progestin-primed ovarian stimulation,PPOS)及全胚胎冷冻移植的背景下,探讨诱发排卵日内源性孕酮(P)水平与多囊卵巢综合征(polycystic ovary syndrome,PCOS)患者体外受精/卵胞质内单精子显微注射(IVF/ICSI)临床结局的关系。方法:回顾性纳入180例PCOS患者行IVF/ICSI-冻融胚胎移植(FET)的资料,所有患者均采用促性腺激素(gonadtropin,Gn)联合孕激素的超促排卵方案,取卵后全部胚胎冷冻,择期行FET,根据诱发排卵日P水平分为A组(P<1.0μg/L,n=125)和B组(P≥1.0μg/L,n=55),比较两组患者的促排卵结局和妊娠结局。结果:A组与B组的Gn总用量(1950.8±384.5 IU vs 1931.2±308.9 IU)及周期治疗时间(11.2±1.4 d vs 11.1±1.1 d)均无统计学差异(P>0.05)。A组诱发日直径>14 mm卵泡数(14.1±7.7 vs21.0±10.3)、获卵数(14.0±7.8 vs 24.1±10.3)、成熟卵数(12.1±7.1 vs 21.1±9.0)、正常受精卵数(9.8±6.1 vs 16.8±8.2)及冷冻胚胎数(5.3±3.6 vs 7.2±3.4)均较B组低,且差异均具有统计学意义。成熟卵率、正常受精卵率、周期取消率、临床妊娠率及种植率组间均无统计学差异(P>0.05)。结论:在FET的前提下,高孕激素超促排卵过程中诱发日内源性P水平的升高提示卵巢反应良好,对PCOS患者的IVF/ICSI临床结局无明显影响。展开更多
基金supported by the Natural Science Foundation of Jiangsu Province (No.BK2006710) the Hi-Tech Research and Development Program (863) of China (No:2003AA601100)
文摘Increasing levels of pollution within water bodies can cause eutrophication and an associated rapid growth in and reproduction of phytoplankton. Although most frequently occurring in bodies of water such as lakes and dams, in recent years an increasing number of river systems in China have suffered serious algal blooms. The community structure of phytoplankton may differ, however, dependent on the hydrodynamic conditions and nutrient levels within the water body. The field investigation results obtained from a stagnant river in Suzhou City and Taihu Lake, China, showed that in water with higher concentrations of nitrogen and phosphorus, Chlorophyta became the predominant species and in water with lower concentrations of nitrogen and phosphorus, Cyanobacteria became the predominant species. Growth experiments with competitive species, Microcystis aeruginosa Kutz and Scenedesmus quadricauda （Turp.）, were conducted at three different nutrient levels. The biomass of algae in pure and mixed cultures was measured under conditions of different N/P ratios at oligotrophic, eutrophic and hypertrophic nutrient levels. The results indicated that the most suitable state for the growth and reproduction of M. aeruginosa and S. quadricauda were eutrophic conditions in both pure and mixed cultures. Under competition, however, the lower medium nutrient levels favoured M. aeruginosa, while the higher medium nutrient levels better suited S. quadricauda. Under similar hydrodynamic conditions, the community structure of phytoplankton in the water body was determined by the dominant species in competition for nutrients.
基金supported by the Ph D Programs Foundation of Ministry of Education of China(20093702110003)the National Key Technology R&D Program of China (2006BAD08A09)
文摘Eleven barnyardgrass populations were assayed. The highest resistant population was Geqiushan R with RI 125.45 resulted from the seed assay and 87.29 resulted from the whole plant bioassay followed by 853 R with RI 2.79 resulted from the seed assay and 6.04 resulted from the whole plant bioassay. The resistance level of other nine populations was low with RI 1.13-2.61 resulted from the seed assay and 1.48-3.63 resulted from the whole plant bioassay. The activity of an important metabolic enzyme glutathione S-transferases （GSTs） and three protective enzymes （SOD, POD, and CAT） were determined in vivo for Geqiushan R, 853 R, and Wudalianchi R. Compared with the S controls, the activities of POD in Geqiushan R, GSTs in 853 R, and Wudalianchi R were increased.
基金supported by the Animal Husbandry and Fishery Bureau Fund of Guangxi Zhuang Autonomous Region Fund"Joint Breeding of New America-line Landrace Pigs"(072410)
文摘[ Objective] To investigate the effects of different nutritional levels on production performance, apparent digestibility of nutrients and car- cass quality, and determine the optimal levels of energy, crude protein, calcium and phosphorus in diet for the Landrace pigs at fattening stage. [ Method] A total of 36 healthy Landrace pigs at the same parity with close weaning age and similar body weight [ （70 ± 1 ） kg ~ were selected. They were divided into nine experimental groups randomly. The experiment was carried out according to the L9 （3^4） orthogonal design. Then the production performance, apparent digestibility of nutrients and carcass quality were determined, respectively. The preliminary trial lasted for 7 d, and the trial lasted for 42 d. [ Result] The levels of crude protein and calcium had significant effects on the average daily gain （ P 〈 0.05）, and the energy level had extremely significant effects on the average daily gain （ P 〈 0.01 ）. The levels of energy, crude protein, calcium and phosphorus had effects on the apparent digestibility of nutrients in various degrees. The crude protein level had significant effects on the backfat P2 （P 〈 0.05） ; the energy level had significant effects on the backfat P2 and backfat P1 （P 〈 0.05） ; and the calcium level had significant effects on backfat P2 and lean meat percentage （P 〈 0.05）. [ Condasion] During the fattening period, the requirement of digestible energy, crude protein, calcium and phosphorus for the new America-line Landrace pills was 13.39 MJ/ka. 16.00%. 1.45% and 0.90%. respectively.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61474110,61377020,61376089,61223005,and 61176126)the National Science Fund for Distinguished Young Scholars of China(Grant No.60925017)+1 种基金One Hundred Person Project of the Chinese Academy of Sciencesthe Basic Research Project of Jiangsu Province,China(Grant No.BK20130362)
文摘The influence of a deep-level-defect（DLD） band formed in a heavily Mg-doped GaN contact layer on the performance of Ni/Au contact to p-GaN is investigated. The thin heavily Mg-doped GaN（p^＋＋-GaN） contact layer with DLD band can effectively improve the performance of Ni/Au ohmic contact to p-GaN. The temperature-dependent I–V measurement shows that the variable-range hopping（VRH） transportation through the DLD band plays a dominant role in the ohmic contact. The thickness and Mg/Ga flow ratio of p^＋＋-GaN contact layer have a significant effect on ohmic contact by controlling the Mg impurity doping and the formation of a proper DLD band. When the thickness of the p^＋＋-GaN contact layer is 25 nm thick and the Mg/Ga flow rate ratio is 10.29%, an ohmic contact with low specific contact resistivity of 6.97×10^-4Ω·cm^2 is achieved.
文摘目的:在高孕激素超促排卵(progestin-primed ovarian stimulation,PPOS)及全胚胎冷冻移植的背景下,探讨诱发排卵日内源性孕酮(P)水平与多囊卵巢综合征(polycystic ovary syndrome,PCOS)患者体外受精/卵胞质内单精子显微注射(IVF/ICSI)临床结局的关系。方法:回顾性纳入180例PCOS患者行IVF/ICSI-冻融胚胎移植(FET)的资料,所有患者均采用促性腺激素(gonadtropin,Gn)联合孕激素的超促排卵方案,取卵后全部胚胎冷冻,择期行FET,根据诱发排卵日P水平分为A组(P<1.0μg/L,n=125)和B组(P≥1.0μg/L,n=55),比较两组患者的促排卵结局和妊娠结局。结果:A组与B组的Gn总用量(1950.8±384.5 IU vs 1931.2±308.9 IU)及周期治疗时间(11.2±1.4 d vs 11.1±1.1 d)均无统计学差异(P>0.05)。A组诱发日直径>14 mm卵泡数(14.1±7.7 vs21.0±10.3)、获卵数(14.0±7.8 vs 24.1±10.3)、成熟卵数(12.1±7.1 vs 21.1±9.0)、正常受精卵数(9.8±6.1 vs 16.8±8.2)及冷冻胚胎数(5.3±3.6 vs 7.2±3.4)均较B组低,且差异均具有统计学意义。成熟卵率、正常受精卵率、周期取消率、临床妊娠率及种植率组间均无统计学差异(P>0.05)。结论:在FET的前提下,高孕激素超促排卵过程中诱发日内源性P水平的升高提示卵巢反应良好,对PCOS患者的IVF/ICSI临床结局无明显影响。
