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To assess the impact of California sea lions (Zalophus californianus) on salmon fisheries in the Monterey Bay region of California, the percentages of hooked fish taken by sea lions in commercial and recreational salmon fisheries were estimated from 1997 to 1999. Onboard surveys of sea lion interactions with the commercial and recreational f isheries and dockside interviews with fishermen after their return to port were conducted in the ports of Santa Cruz, Moss Landing, and Monterey. Approximately 1745 hours of onboard and dockside surveys were conducted—924 hours in the commercial fishery and 821 hours in the recreational fishery (commercial passenger fishing vessels [CPFVs] and personal skiffs combined). Adult male California sea lions were responsible for 98.4% of the observed depredations of hooked salmon in the commercial and recreational fisheries in Monterey Bay. Mean annual percentages of hooked salmon taken by sea lions ranged from 8.5% to 28.6% in the commercial fishery, 2.2% to 18.36% in the CPFVs, and 4.0% to 17.5% in the personal skiff fishery. Depredation levels in the commercial and recreational salmon fisheries were greatest in 1998—likely a result of the large El Niño Southern Oscillation (ENSO) event that occurred from 1997 to 1998 that reduced natural prey resources. Commercial fishermen lost an estimated $18,031−$60,570 of gear and $225,833−$498,076 worth of salmon as a result of interactions with sea lions. Approximately 1.4−6.2% of the available salmon population was removed from the system as a result of sea lion interactions with the fishery. Assessing the impact of a growing sea lion population on fisheries stocks is difficult, but may be necessary for effective fisheries management.

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The worldwide literature on management of spotted seals, Phoca largha, was reviewed and updated, and aerial surveys weref lown in 1992 and 1993 to determine the species' distribution and abundance in U.S. waters. In April, spotted seals were found only in the Bering Sea ice front. In June, they were seen along deteriorating ice floes and fast ice in Norton Sound. Surveys along most of Alaska's western coast in August and September found over 2,500 spotted seals in Kuskokwim Bay and concentrations of 100-400 seals around Nunivak Island, Scammon Bay, Golovnin Bay/Norton Sound, Cape Espenberg/Kotzebue Sound, and Kasegaluk Lagoon. All of these sites have been used by spotted seals in the past. The sum of the highest counts, irrespective of year, was 3,570 seals (CV =0.06). This is not an abundance estimate for all spotted seals in the Bering Sea, because it does not account for animals in the water, and we did not survey the Asian coast and some islands. Also, spotted seals and harbor seals, Phoca vitulina, are too similar in appearance to be identified accurately from the air, so our results probably include a mix of these species where their ranges overlap.

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The charter boat industry in U. S. Gulf of Mexico provides access to offshore fishing opportunities for about 570,000 passengers per year on 971 boats. A 25% random sample of charter boat operators was interviewed during 1987-88 to determine species targeted, percent time committed to targeting each species, and reactions to existing catch restrictions. Three-fourths of the charter boat fleet was in Florida, 13% in Texas, 5% in Louisiana, 4% in Alabama, and 2% in Mississippi. Responses were diverse regarding species focus within the region. Species of dominant importance included groupers, Epinephelus sp. and Mycteroperca sp. (Fla.); snapper, Lutjanus campechanus (Ala., Fla., Miss., and La.); king mackerel, Scomberomorus cavalla (Miss., Tex., Ala. and Fla.); spotted seatrout, Cynoscion nebulosus (Tex. and La.); and red drum, Sciaenops ocellatus (Tex. and La). Catch restrictions were generally supported with higher levels of opposition to restricted high effort fish and/or one fish or closed fishery limits.

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Este estudo foi realizado para investigar os níveis de leptina no fluido de endometriomas ovarianos e comparar a expressão de leptina e seus receptores no tecido ovariano afetado por endometrioma de mulheres inférteis com a sua expressão no tecido ovariano normal de controles férteis sem endometriose. Neste estudo observacional, o tecido ovariano , amostras de sangue e fluido peritoneal foram obtidas de 20 mulheres (10 controles férteis sem endometriose ou qualquer doença ovariana, que foram submetidos à cirurgia de laqueadura tubária e 10 mulheres inférteis com endometriose grave endometrioma ovariano). O fluido contido no endometrioma ovariano foi aspirado, e biópsias de implantes peritoneais foram realizadas. Os tecidos removidos durante as cirurgias foram imediatamente congelados em nitrogênio líquido para determinação da expressão proteica por western blot e níveis de leptina pelo ELISA. A expressão do receptor de leptina foi maior no tecido do ovariano afetado por endometrioma que no tecido de ovariano normal (controle= 0,38 0,05, estudo= 0,60 0,09, p= 0,03), mas não houve diferença significativa nos níveis de leptina entre estes grupos (controle= 0,1 0,57, estudo= 0,1 0,35, p= 0,18). Foram observadas correlações positivas e significativas entre a leptina e seu receptor no endometrioma ovariano (r = 0,85, p = 0,004) e em implantes peritoneais (r= 0,87, p= 0,001). Os resultados do ELISA demonstraram uma maior concentração de leptina no fluido endometrioma em comparação com a leptina sérica e no fluido peritoneal (soro= 8,4 1,0, FP= 1,6 0,5, FE= 73,8 16,2, p= 0,0001), mas não houve correlação entre estas variáveis. Observou-se uma correlação positiva, significativa e forte entre os níveis de leptina no fluido peritoneal e a expressão de leptina e seu receptor em implantes peritoneais (leptina: r= 0,88, p= 0,0008; OBR: r= 0,96, p= 0,0001) e entre os níveis de leptina no fluido endometrioma e a expressão da leptina e seu receptor no endometrioma ovariano (leptina: r= 0,94, p= 0,001; OBR: r = 0,84, p= 0,02). Nossos resultados sugerem que a leptina pode desempenhar um papel importante na fisiopatologia do endometrioma ovariano por meio de uma interação moduladora com o seu receptor.

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光系统II(PSII)是存在于类囊体膜中的多亚基色素蛋白复合物,是吸收光能、催化光诱导水裂解释放氧气、质子和电子的重要机构。它在体内的基本单位是由外周天线蛋白(LHCII)与PSII核心复合物结合形成的PSII-LHCII超分子复合物,这一结构保证了LHCII吸收的能量能够快速有效的传递到PSII反应中心(RC),进行原初光化学反应。 本论文分为两部分:1、利用捕光色素蛋白复合物(LHCII)与PSII核心复合物在以DGDG、PG、SQDG三种类囊体膜脂形成的脂质体中重组的方法,研究了LHCII与PSII在脂膜上结构与功能的相互作用;2、通过研究光破坏和色素置换对PSII RC的影响,探讨了RC中不同色素的功能。主要结果如下: 1、LHCII与PSII核心复合物的蛋白脂质体研究: 将OECC(粗提核心复合物)、pdOE(纯化核心复合物)、LHCII(大量天线)制剂分别与脂质体重组并研究了其光谱性质。LHCII在与脂质体重组前表现出典型的聚集态光谱特征,重组后吸收和荧光发射峰发生明显蓝移;LHCII、OECC和pdOE三种蛋白脂质体与重组前的样品相比荧光发射强度增加;表明脂环境影响了色素蛋白复合物的聚集状态以及色素和蛋白之间的相互作用。 OECC和pdOE分别与LHCII在脂质体中重组,得到两种重组蛋白(LHCII-OECC和LHCII-pdOE)脂质体,用冰冻蚀刻电镜技术和低温荧光光谱的方法研究其结构和功能特征。LHCII和核心复合物(OECC或pdOE)结合形成PSII-LHCII重组颗粒,并在脂质体中均匀排布,阻止了LHCII晶格状结构的形成。重组蛋白脂质体的吸收光谱既有LHCII的吸收特征,又有核心复合物的特征吸收峰,但低温荧光光谱的主要发射峰是核心复合物的特征峰(684 nm-685 nm),而不是LHCII的特征峰(680 nm);而且激发不同色素得到的荧光发射光谱基本一致,这些结果证明LHCII吸收的能量传递到了核心复合物中,在重组蛋白脂质体中不同色素蛋白复合物在结构和功能上都实现了相互偶联。 通过对OECC或pdOE与LHCII重组形成的蛋白脂质体放氧或DCPIP光还原活性的检测研究了PSII光化学活性特征。LHCII和核心复合物(OECC或pdOE)的重组蛋白脂质体与单独核心脂质体相比,在强光和弱光下光化学活性都明显提高。这从另一个角度证明了核心复合物与LHCII的功能偶联,LHCII的结合使捕光截面积增大,从而使PSII光化学活性增加。 用77K飞秒时间分辨荧光光谱分析了几种蛋白脂质体的能量传递和捕获情况。LHCII、OECC和pdOE三种蛋白脂质体的主要荧光衰减组分分别是670 ps(发射峰在680 nm)、650 ps(发射峰在690 nm)和570 ps(发射峰在685 nm)。LHCII-OECC和LHCII-pdOE脂质体的主要衰减组分分别是940 ps(发射峰在690 nm)和840 ps(发射峰在685 nm),并且出现了一个在核心复合物脂质体和LHCII脂质体中没有的40 ps组分,可以推测,这是LHCII和核心复合物之间达到平衡的时间组分,比激发态衰减的平均寿命要快得多,因此支持了PSII的trap-limited激发能衰减动力学模型。此外,可以看到天线的增大使Chl a荧光衰减的寿命延长,这一特性可能与PSII的光保护机制有关。 LHCII和OECC、LHCII和pdOE在脂质体中都成功的实现了重组,而且在结构和功能上没有明显差异;表明小天线以及23 kDa、17 kDa蛋白可能不是LHCII和核心复合物结合及能量传递所必需的。 2、受体侧光破坏和色素置换对PSII RC的影响: 在800 μmol.m-2 .s-1光照和无外加电子受体、供体的情况下,研究了PSII RC色素的受体侧光破坏情况。Chl a、Pheo和β-Car的光漂白几乎同时发生,其中在680 nm吸收的色素破坏最为显著,670 nm吸收的外周Chl比其他色素更加稳定。荧光发射强度呈先升高后降低的趋势,最大发射峰位逐渐蓝移,表明色素之间的能量传递受到破坏。用β-Car的主要吸收波长488 nm和514.5 nm激发得到两组谱带峰位和强度不同的拉曼光谱,表明在PSII RC中存在两个光谱性质不同的β-Car。光破坏过程中两组谱带的位置和带宽都没有明显变化,表明β-Car的光保护机制不涉及自身构象的变化。 将PSII RC与Cu-Chl a进行色素置换,得到了与Cu-Chl重组的RC(Cu-Chl-RC),含有0.5 Cu-Chl/2Pheo。与对照RC(按同样方式与Chl a置换的RC)和天然RC相比,Cu-Chl含量增加而Chl含量减少,660 nm的吸收增加而670 nm吸收降低,因此推测是外周Chl被替换。色素置换过程对RC的多肽组分及大部分的P680活性没有影响,CD光谱的变化也很小,表明产生CD信号的色素和蛋白环境也没有受到明显影响。但是Cu-Chl-RC的荧光发射强度明显降低,最大发射峰蓝移且峰形发生变化,Cu-Chl可能在重组RC中作为激发态的淬灭剂,阻碍了色素之间的能量传递。

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The regression coefficients in length-weight relationship of males and females of Tachysurus tenuispinis differ significantly. The relative condition factor was calculated for females in relation to various lengths and months. The sex ratio in the catch varied widely in the different months. The number of eggs ranged from 72 to 89 for the fish of length 394 to 570 mm. Empty stomachs occurred in a very high percentage (63.5%) of the total stomachs examined. This is a bottom carnivorous feeder. The main food items found in the guts in order of preference were crustaceans, polychaetes, molluscs, fishes and echinoderms.