Horizontal and vertical movements of juvenile bluefin tuna (Thunnus thynnus) in relation to oceanographic conditions of the western North Atlantic, determined with ultrasonic telemetry

We employed ultrasonic transmitters to follow (for up to 48 h) the horizontal and vertical movements of five juvenile (6.8–18.7 kg estimated body mass) bluefin tuna (Thunnus thynnus) in the western North Atlantic (off the eastern shore of Virginia). Our objective was to document the fishes’ behavior and distribution in relation to oceanographic conditions and thus begin to address issues that currently limit population assessments based on aerial surveys. Estimation of the trends in adult and juvenile Atlantic bluefin tuna abundance by aerial surveys, and other fishery-independent measures, is considered a priority. Juvenile bluefin tuna spent the majority of their time over the continental shelf in relatively shallow water (generally less then 40 m deep). Fish used the entire water column in spite of relatively steep vertical thermal gradients (≈24°C at the surface and ≈12°C at 40 m depth), but spent the majority of their time (≈90%) above 15 m and in water warmer then 20°C. Mean swimming speeds ranged from 2.8 to 3.3 knots, and total distance covered from 152 to 289 km (82–156 nmi). Because fish generally remained within relatively con-fined areas, net displacement was only 7.7–52.7 km (4.1–28.4 nmi). Horizontal movements were not correlated with sea surface temperature. We propose that it is unlikely that juvenile bluefin tuna in this area can detect minor horizontal temperature gradients (generally less then 0.5°C/km) because of the steep vertical temperature gradients (up to ≈0.6°C/m) they experience during their regular vertical movements. In contrast, water clarity did appear to influence behavior because the fish remained in the intermediate water mass between the turbid and phytoplankton-rich plume exiting Chesapeake Bay (and similar coastal waters) and the clear oligotrophic water east of the continental shelf.

Vertical and horizontal movements of southern bluefin tuna (Thunnus maccoyii) in the Great Australian Bight observed with ultrasonic telemetry

The vertical and horizontal movements of southern bluefin tuna (SBT), Thunnus maccoyii, in the Great Australian Bight were investigated by ultrasonic telemetry. Between 1992 and 1994, sixteen tuna were tracked for up to 49 h with depth or combined temperature-depth transmitting tags. The average swimming speeds (measured over the ground) over entire tracks ranged from 0.5 to 1.4 m/s or 0.5 to 1.4 body lengths/s. The highest sustained swimming speed recorded was 2.5 m/s for 18 hours. Horizontal movements were often associated with topographical features such as lumps, reefs, islands and the shelf break. They spent long periods of time at the surface during the day (nearly 30%), which would facilitate abundance estimation by aerial survey. At night, they tended to remain just below the surface, but many remained in the upper 10 m throughout the night. SBT were often observed at the thermocline interface or at the surface while travelling. A characteristic feature of many tracks was sudden dives before dawn and after sunset during twilight, followed by a gradual return to their original depth. It is suggested that this is a behavior evolved to locate the scattering layer and its associated prey when SBT are in waters of sufficient depth. SBT maintained a difference between stomach and ambient temperature of up to 9°C.

Induced breeding, embryonic and larval development in Heteropneustes fossilis (Bloch) in the agro-climatic conditions of Maharashtra

Heteropneustes fossilis was induced bred for the first time in the agro-climatic conditions of Maharashtra, India. The embryonic development was completed within 16-18h after fertilisation. Head and tail ends were distinguishable after 3h and 11-12 somites were visible after 6-7h. The eggs started hatching after 14h of incubation. Average hatching time was 16-18h at 26 degrees C. In first day old pro-larva, notochord was deflected upwards, eyes were darkly pigmented and alimentary canal appeared. In fourth day old post-larva intestinal coiling could be seen and yolk was absorbed. Aerial respiration started by 8th day. The 10 day old post-larva was free swimming and fed voraciously attaining a length of 20 mm in 30 days.

Heat budget studies of the north Arabian Sea during summer and winter seasons, 1992

In this study heat budget components and momentum flux for August and January 1992 over the north Arabian Sea are computed. The marine meteorological data measured on board during the cruises of PAK-US joint project (NASEER) are used for the computation. Significant differences were found in the heat budget components as well as in the momentum flux during different monsoon periods over the north Arabian Sea. The latent heat flux was always positive and attributed to the large vapour pressure gradient. The computed moisture and latent heat fluxes in January were higher than August The highest value of latent heat flux 309 W/m2 at station 8 was evaluated. These higher latent heat fluxes were due to the large vapour pressure gradient, air-sea temperature difference, the wind speed, and the prevailing wind direction (from north and northeast). Negative values of sensible heat fluxes in both seasons indicate that the heat transfer was from the atmosphere to the ocean. The negative values of net heat gain indicate that the sea surface field became an energy sink: or the sea surface supplied more energy to the atmosphere than it received from it. Large variation in the momentum flux mainly attributed to the variation in the wind speed. Aerial averages of heat and momentum fluxes were also computed.

Four new dibenzocyclooctadiene lignans from Schisandra rubriflora

From the aerial parts of Schisandra rubriflora (FRANCH) REHD. et WILS., four new dibenzocyclooctadiene lignans, methylgomisin R (1), (+)-14-tigloylgomisin K-3 (2), 12-demethylwuweilignan I (3), schisandrene A (4), together with 13 known lignans, were isol

Periglaucines A-D, anti-HBV and -HIV-1 alkaloids from Pericampylus glaucus

Four new hasubanane-type alkaloids, periglaucines A-D (1-4), and three known alkaloids, norruffscine (5), (-)-8-oxotetrahydropalmatine (6), and (-)-8-oxocanadine (7), were isolated from the aerial parts of Pericampylus glaucus. Their structures were eluci

Lignans with Anti-HIV Activity from Schisandra propinqua var. sinensis

Fourteen new lignans, tiegusanins A-N (1-14), together with 13 known compounds were isolated from the aerial parts of Schisandra propinqua var. sinensis. The structures and absolute configurations of 1-13 were established using a combination of spectrosco

Study of density, distribution and yield on benthic fauna and brown trout (Salmo trutta fario) feeding in Laar reservoirs

Lar lake, with the international UTM specification of 39S 579680 3976567 & 39S 589930 3976184 is Situated in Lar national Park with an aerial distance of 55 Km of Tehran along Haraz road. The present research is carried out as part of a comprehensives Plan for assessment of bioresearches of Lar lake & the rivers flowing into it. This research includes examination of there benthic Samplings performed in Lar lake and each of the related rivers including Delichaee, Ab-e-sefid , Alarm & Lar (Kamardasht).Tubifex and Chironomus genus were found to have the highest frequencies of occurrence in the lake with %77.117 & %21.823 respectively followed by Chironomidae and Simulidae from the Diptera order which accounted for %72.328 and %13.812 occurrences in four rivers examined in the Study. The benthic biomass at various examined Sites and the average wet weight of the benthic biomass in station No one in the lake Was 17.397g and the figure for the examined site in Alarm was 20.242 g which were the highest level among Other examination stations the index for the abundance of species in Alarm river was greater than the rest of the examined rivers with 12.57. A sum of 354 Pieces of brown trouts was caught in the course of sampling which were closely investigated in terms of their digestive tract Content. It was identified that Daphniidae and Chironomus constituted the bulk of eaten items from the lake with %17.985 and %63.973 respectively. Meanwhile, Chironomidae and Simuladae were the most frequently eanten benthos by the fish with %81.47 and %7.93 respectively.The index for the relative length of gut was recorded at 0.49± 0.08 which is well indicative of the carnivorous diet of the fish.The index for the feeding intensity amounted to 138  83 showing that the one year old fish were of more feeding intensity.The coefficient of condition (K) was estimated at 1.02  0.142 for all the caught fish. The average wet weight of the benthos was 10.348 g per square meter which if extended to 700ha surface area of the lake, the total macrobenthic production in the lake would amount to 72730Kg of wet weight or 6510 Kg of dry weight. Since the Secondary Production of macrobenthos have always been double that of their biomass, it is reasonable to assume that the Secondary Production of macrobenthos amount to 145640 Kg by their wet weight and Since the energy transfer in the food chain of the lake from benthos to fish is 10 percent, the fish production Capacity Coming from benthic resources of the lake (Lar) would be 14.5 MT, half of which (7000-8000MT) could annually be harvested. Further more, the actual fish Production Capacity might exceed the projected level Since Daphnia, Rotifers and Ostracoda which belong to Zooplanktons, play a part in the natural diet of trout. Meanwhile, rivers Play a major role in fish nutrition and the annual fish production in Delichaee river is about 4481.8Kg while the figures for Ab-e-sefid, Alerm and Lar rivers are 2370.7 4848.7 and 2586.2 Kg respectively, that further increase fish Production in the area and every year half of these resources can be exploitable from the river & the lake.Nevertheless, due to ecological & biological importance of rivers and the probability of environmental Pollution, devastation of natural fish habitats & their nursery grounds, Sport fishing is not recommended at all.

Habitat degradation of Rhinopithecus bieti in Yunnan, China

Black-and-white snub-nosed monkeys (Rhinopithecus bieti) are endemic to the Trans-Himalayas in Northwest Yunnan and Southeast Tibet between the upper Yangtze and Mekong Rivers. Based on field surveys and previous reports, we identified the dark-coniferous forest, the mixed coniferous and broadleaf forest, and oak patches as suitable habitats (SH) for the monkeys. Summer grazing lands (SGL), which were made by local people cutting and burning the dark-coniferous forest at the high altitude belt, replaced SH. To have a general view of the status of the SH in Yunnan, we estimated the areas of SH and SGL from satellite images in 1997, and compared with areas estimated from aerial photo-based maps (ca. 1958). The work resulted in: 1) the area of SH was 4,169 km(2) in 1997; 2) SGL was 1,923 km(2); 3) during the past 40 years, the area of SH decreased by 31% (1,887 km(2)), and SGL increased by 204% (1,291 km(2)); and 4) the mean size of forest patches decreased from 15.6 to 5.4 km(2). In addition, the area of SGL is positively correlated to local human population (R-2 greater than or equal to0.53), implying that the reduction and fragmentation of habitat for Rhinopithecus bieti is a result of population growth of humans, who mostly employ traditional modes of production. Only 11 monkey groups remained in the changing habitat. Considering that forests at lower elevation were also encroached upon by farmlands in a similar way, the forest ecosystem is highly threatened. The destruction will continue unless there is a change in the mode of production in the region.

Daily timing of emersion and elevated atmospheric CO2 concentration affect photosynthetic performance of the intertidal macroalga Ulva lactuca (Chlorophyta) in sunlight

The lunar day differs in length from the solar day so that times of low tide vary from day to day. Thus, aerial exposure of intertidal seaweeds may be during the day or during the night. We measured photosynthetic CO, assimilation rates of the intertidal green macroalga Ulva lactuca during exposures of varied daily timings during sunny days of summer to establish how photosynthetic performance responds to emersion timing under varied CO2 levels [at ambient (360 ppmv) and 2x ambient (720 ppmv) atmospheric CO2 concentrations]. There was an increase in net photosynthetic rates following some duration of exposure when the initial timing of exposure occurred during early morning (06.30 h) and late afternoon (17.15 h). In contrast, net rates exhibited a sharp decline with exposure duration when the initial timing of exposure occurred at 09.30 h, 15.30 h and especially at noon (12.30 h), implying the occurrence of a severe photoinhibition resulting from mid-day insolation. Doubled atmospheric CO2 concentration significantly enhanced the emersed photosynthetic rates, indicating that the emersed photosynthesis is CO2-limited at ambient CO2 levels. However, increasing CO2 barely stimulates the emersed photosynthetic rates during mid-day insolation.

Diurnal changes of behavior and respiration of Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) in captivity

A preliminary study was carried out to investigate diurnal changes of behavior of three, one adult mate, one adult female, and one juvenile female, Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) in captivity. The respiration and behavior of the porpoises were recorded for 222 hr across 42 days. Behavioral data were recorded for eight general categories: aerial display and fast swimming, begging for fish, playing, nonsexual socializing, sexual behavior, resting, rubbing, and miscellaneous (i.e., other behaviors not included in the above categories). Each behavioral category was scored using one-zero sampling with 10-min intervals. The adult male showed shorter mean respiratory intervals at night (19:00-7:00 h), whereas the mean respiratory intervals of the females were shorter during the day (7:00-19:00 h). Begging for fish of all individuals, playing of the juvenile female, nonsexual socializing, and miscellaneous behavior of the adult female and resting of the male were observed more easily in the day, and aerial display and fast swimming of the adults and resting of the females were observed more easily at night. No significant diurnal difference was found, however, in the remaining categories of each individual. Each of the three porpoises therefore showed a distinct diurnal pattern, but none was obviously more active in the daytime than during the nighttime. Results suggest that daytime-only feeding schedules may be insufficient to meet the energetic needs of marine mammals that show a 24-hr activity cycle, and that nighttime feeding may be a worthwhile addition to husbandry routines.

Ecophysiological characteristics of four intertidal marine macroalgae during emersion along Shantou coast of China, with a special reference to the relationship of photosynthesis and CO2

Intertidal marine macroalgae experience periodical exposures during low tide due to their zonational distribution. The duration of such emersion leads to different exposures of the plants to light and aerial CO2, which then affect the physiology of them to different extents. The ecophysiological responses to light and CO2 were investigated during emersion in two red algae Gloiopeltis furcata and Gigartina intermedia, and two brown algae Petalonia fascia and Sargassum hemiphyllum, growing along the Shantou coast of China. The light-saturated net photosynthesis in G. furcata and P. fascia showed an increase followed by slightly desiccation, whereas that in G. intermedia and S. hemiphyllum exhibited a continuous decrease with water loss. In addition, the upper-zonated G. furcata and P. fascia, exhibited higher photosynthetic tolerance to desiccation and required higher light level to saturate their photosynthesis than the lower-zonated G. intemedia and S. hemiphyllum. Desiccation had less effect on dark respiration in these four algae compared with photosynthesis. The light-saturated net photosynthesis increased with increased CO2 concentrations, being saturated at CO2 concentrations higher than the present atmospheric level in G. furcata, G. intermedia and S. hemiphyllum during emersion. It was evident that the relative enhancement of photosynthesis by elevated CO, in those three algae increased, though the absolute values of photosynthetic enhancement owing to CO2 increase were reduced when the desiccation statuses became more severe. However, in the case of desiccated P. fascia (water loss being greater than 20 %), light saturated net photosynthesis was saturated with current ambient atmospheric CO2 level. It is proposed that increasing atmospheric CO2 will enhance the daily photosynthetic production in intertidal macroalgae by varied extents that were related to the species and zonation.

Biologically inspired visual odometer for navigation of a flying robot

Experimental research in biology has uncovered a number of different ways in which flying insects use cues derived from optical flow for navigational purposes, such as safe landing, obstacle avoidance and dead reckoning. In this study, we use a synthetic methodology to gain additional insights into the navigation behavior of bees. Specifically, we focus on the mechanisms of course stabilization behavior and visually mediated odometer by using a biological model of motion detector for the purpose of long-range goal-directed navigation in 3D environment. The performance tests of the proposed navigation method are conducted by using a blimp-type flying robot platform in uncontrolled indoor environments. The result shows that the proposed mechanism can be used for goal-directed navigation. Further analysis is also conducted in order to enhance the navigation performance of autonomous aerial vehicles. © 2003 Elsevier B.V. All rights reserved.

毛蕊异黄酮类似物的合成及其对JAK/STAT信号途径调控的构效关系研究

干扰素（IFNs）是最早发现的具有广泛用途的一类细胞因子，IFN-α通过JAK/STAT信号途径调控机体一系列生理和病理反应。至今尚未发现类干扰素的小分子。我们前期研究发现天然产物毛蕊异黄酮可激活干扰素诱导的JAK/STAT信号途径。为发现类干扰素小分子、获得小分子探针，本课题拟建立成熟的JAK/STAT信号途径的筛选模型，合成毛蕊异黄酮及其类似物，研究这些化合物的构效关系，进而尝试通过共价键标记生物素或香豆素来直接研究它们与相关受体的作用。 从异香草醛出发经7步合成反应得到了毛蕊异黄酮。采用平行合成策略得到异黄酮类化合物；采用分支式合成策略，以取代苯乙酸作为合成砌块，获得具有与异黄酮类似结构的香豆素、3-芳基喹诺酮。与分离得到的黄酮类化合物，构建了一个包括异黄酮、黄酮、香豆素、3-芳基喹诺酮在内的化合物库。 建立了包含IFN-α刺激反应元件 (ISRE)的荧光素酶报告基因体系，通过筛选化合物库中的化合物，发现异黄酮骨架为激活JAK/STAT信号途径必须结构、毛蕊异黄酮7-位酚羟基被取代后活性丧失。根据以上结果，对毛蕊异黄酮3′-位标记物的合成进行了初步尝试。 发现山茱萸科植物青荚叶(Helwingia japonica (Thunb.) Dietr.)有抑制蛋白酪氨酸磷酸酯酶1B（PTP1B）的活性。从其地上部分95%乙醇提取物的乙酸乙酯部分分离得到5个化合物,应用波谱方法及与已知品对照的手段鉴定它们为p-menth-2-en-1β, 4β, 8-triol (Z-1)、blumenol A (Z-2)、2′,3′,4′,5′,6′-五羟基查尔酮(Z-3)、洋芹素7-O-β-D-吡喃葡萄糖苷(Z-4)、木犀草素7-O-β-D-吡喃葡萄糖苷(Z-5). Interferons (IFNs) are one kind of cytokines with broad functions. IFN-α mediates series physiological and pathological changes of human body via JAK/STAT pathway. Untill now, no IFNs-like small molecules are discovered. In our preliminary experiment, the natural product calycosin has been observed to activate JAK/STAT pathway. Therefore, we establish a luciferase reporter gene system and synthesize calycosin and its analogues to reveal their structure-activity relationship (SAR). Besides, in order to prove that calycosin activates JAK/STAT pathway through IFN receptor, we attempted to tag it with biotin or coumarin by covalent bonding. Calycosin was synthesized from isovanillin via seven steps. Other isoflavones were obtained by parallel synthesis; coumarins and quinolones were prepared through divergent synthesis, using substituted phenylacetic acids as building blocks. Combing with natural flavones, a small molecule library was established. A luciferase reporter gene system, consisting of 5 copies of the ISRE (interferon-stimulated response element), was used for screening of small molecules from that library. We found that the core-structure of isoflavone was necessary, and if the 7-OH is substituted, the activity slumps. According to our observation, we tried to tag biotin or coumarin at 3′-OH of calycosin. The 95% ethanol extract of the aerial parts of Helwingia japonica (Thunb.) Dietr. showed protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Five compounds were isolated. On the basis of spectral data or by comparison with authentic samples, they were identified as p-menth-2-en-1β,4β,8-triol (1), blumenol A (2), 2′,3′,4′,5′,6′-pentahydroxychalcone (3), apigenin 7-O-β-D-glucopyranoside (4), and luteolin 7-O-β-D-glucopyranoside (5).

野桂花的化学成分研究

首次从野桂花（Osmanthus yunnanensis Fr. P. S. Green）地上部分95%乙醇提取物中通过色谱分离得到20个化合物, 其中化合物20为新化合物。基于波谱数据它们被鉴定为(E)-阿魏酸二十烷基酯(1)、β-谷甾醇(2)、羽扇豆醇(3)、齐墩果酸(4)、7-oxo-β-sitosterol(5)、乙酰齐墩果酸(6)、(6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside(7)、rotundioic acid(8)、地榆糖甙Ⅱ(9)、27-O-(E)-对羟基肉桂酰-28-齐墩果酸(10)、27-O-(Z)-对羟基肉桂酰-28-齐墩果酸(11)、hycandinic acid ester(12)、绿原酸丁酯(13)、4,5-二咖啡酰奎尼酸丁酯(14)、4,5-dihydroxyprenyl caffeate(15)、28-O-β-D-glucopyranosyl rotundioic acid (16)、4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada-glycoside C, 17)、 4-β-D-glucopyranosyloxy-5-hydroxy-prenyl caffeate (aohada-glycoside A, 18)、β-胡萝卜甙(19)以及3-[O-β-D-(6-O-咖啡酰吡喃葡萄糖)]-甲基-2-烯-γ-内酯 (20)。化合物13、14、15和17有较强的α-葡萄糖甙酶抑制活性。当浓度为1 mg/ml时，它们对α-葡萄糖甙酶的抑制分别为61.5%、95.5%、72.1%、62.6%，活性高于阿卡波糖。 综述了木犀属植物化学成分及1993年以来苯丙素甙类化合物活性研究进展。 Twenty compounds were isolated from the 95% ethanol extract of the aerial parts of Osmanthus yunnanensis Fr. P. S. Green by chromatography for the first time. On the basis of spectral data, they were identified as (E)-ferulic acid eicosyl ester (1), β-sitosterol (2), lupenol (3), oleanolic acid (4), 7-oxo-β-sitosterol (5), acetyloleanolic acid (6), (6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside (7), rotundioic acid (8), ziyu glycosideⅡ (9), 3β-hydroxy-27-p-(E)-coumaroyloxy-olean-12-en-28-oic acid (10), 3β-hydroxy-27-p-(Z)-coumaroyloxyolean-12-en-28-oic acid (11), hycandinic acid ester (12), chlorogenic acid butyl ester (13), 4,5-di-O-caffeoylquinic acid butyl ester (14), 4,5-dihydroxyprenyl caffeate (15), 28-O-β-D-glucopyranosyl rotundioic acid (16), 4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada- glycoside C, 17), 4-β-D-glucopyranosyloxy-5-hydroxyprenyl caffeate (aohada- glycoside A, 18), β-daucosterol(19) and 3-[O-β-D-(6-O-caffeoylglucopyranosyl)]- methyl-2-en-γ-lactone (20). Compound 20 is a new one. Compounds 13, 14, 15 and 17 inhibit α-glucosidase with corresponding inhibitory rate of 61.5%, 95.5%, 72.1% and 62.6% at a concentration of 1 mg/ml, higher than acarbose. The chemical studies on Osmanthus genus and bioactivities of phenylpropanoid glycosides were summarized.