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1.
为探究单翼迷宫式滴灌带坡度、进水压力和铺设长度对灌水均匀度的影响,以3种单翼迷宫式滴灌带为研究对象,以灌水均匀度作为评价指标,采用UL9(34)均匀正交设计试验,比较了3种不同流量的单翼迷宫滴灌带在进水压力、铺设长度和坡度作用下的灌水均匀度的变化规律.经直观分析、方差分析和多重比较进行综合评价,再由SPSS和PPR对试... 相似文献
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İsmail Hakkı Nur William Pérez Horst Erich König 《Anatomia, histologia, embryologia》2021,50(3):658-667
This study aims to reveal the morphological properties of facial nerve and the middle ear in Van cats. Study material was composed of 6 female Van cats. Dissections were performed under a Zoom Stereo Microscope. There was no plexus buccalis in Van cats. The chorda tympani was observed to pass through an opening in the tympanic cavity, emerge through a small opening just behind the retroarticular process, and join the lingual nerve. A rounded anatomical formation with a size of 2.75 ± 0.3 mm was found to be located within the mastoid process of the temporal bone between the facial nerve and the auricular branch of the vagus nerve. The stapes nerve was not present. The geniculate ganglion was very prominent and about 1.00 mm high. The deep petrosal nerve was observed to emerge from the plexus tympanicus. The bulla tympanica was 18.96 ± 0.10 mm long, 13.03 ± 0.20 mm wide and 13.16 ± 0.20 mm high. After leaving the mandibular nerve, the n.tensoris tympani coursed caudally around the a.maxillaris, formed an ansa, entered the tympanic cavity through the canalis musculotubarius and reached an end in the m. tensor tympani. Due to the scarcity of studies on the middle ears of Van cats, it is thought that this study will fill a gap in the field of veterinary anatomy. 相似文献
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Digestibility,growth and pigmentation of astaxanthin,canthaxanthin or lutein diets in Lake Kurumoi rainbowfish,Melanotaenia parva (Allen) cultured species
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Nina Meilisza Dedi Jusadi Muhammad Zairin Jr. I Made Artika Nur Bambang Priyo Utomo Tutik Kadarini Muhammad Agus Suprayudi 《Aquaculture Research》2017,48(11):5517-5525
New cultured ornamental fish namely Lake Kurumoi rainbowfish Melanotaenia parva (Allen) run into reduced of colour performances when reared in the aquaria, consequently, fish feed must be added with carotenoids as a pigment source. The aim of this study was to evaluate the digestibility, growth and pigmentation of astaxanthin, canthaxanthin and lutein in diet. Apparent digestibility coefficients (ADC) of dry matter, lipid, protein, carotenoids, growth and pigmentation were studied in twenty fish after 14 and 56 days of observation. The single‐dose supplementation of 100 mg/kg of astaxanthin, canthaxanthin, or lutein diets on fish was fed by apparent satiation. The basal diet without carotenoids was used as control. The result showed that the ADC of carotenoids of test diets was higher compared to control. Fish fed astaxanthin diet had higher survival rate (96.67 ± 2.89%), colour measurements of lightness (57.60 ± 7.46%), a*‐values (4.66 ± 1.20), total carotenoids content in skin (33.75 ± 5.02 mg/kg) and muscle (2.16 ± 0.74 mg/kg). Astaxanthin also increased the growth after 14 days (2.00% ± 0.19%/days) but there was no significantly different at the end of experiment. The yellowish‐orange colour performance was more rapidly achieved by fish fed astaxanthin diet after 28 days experimentation. These values suggested that dietary carotenoids were required and astaxanthin diet was superior to other diets for skin pigmentation of Lake Kurumoi rainbowfish. 相似文献
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David G Ainley Nadav Nur Joseph T Eastman Grant Ballard Claire L Parkinson Clive W Evans Arthur L. DeVries 《Fish and Fisheries》2013,14(3):343-363
We report the analyses of a dataset spanning 39 years of near‐annual fishing for Dissostichus mawsoni in McMurdo Sound, Antarctica, 1972–2011. Data on total length, condition and catch per unit effort (CPUE) were derived from the > 5500 fish caught, the large majority of which were measured, tagged and released. Contrary to expectation, the length frequency of the McMurdo Sound catch was dominated by fish in the upper two‐thirds of the overall distribution exhibited in the industrial catch for the Ross Sea shelf. Fish length and condition increased from the early 1970s to the early 1990s and then decreased. Fish length positively correlated with Ross Sea ice extent in early spring, a relationship possibly caused by more ice encouraging larger fish to move farther south over the shelf and into the study area. Fish condition positively correlated with the amount of open water in the Ross Sea during the previous summer (Feb), perhaps reflecting greater availability of prey with the higher productivity that more open water brings. Decreasing fish size corresponds to the onset of the fishery, which targets the large individuals. CPUE was constant through 2001 and then decreased dramatically. We hypothesize that this decrease is related to the industrial fishery, which began in the 1996–97 austral summer, and concentrates effort over the ice‐free Ross Sea continental slope. As a result of limited prey choices and close coupling among mesopredators of the region, Antarctic toothfish included, the fishery appears to be dramatically altering the trophic structure of the Ross Sea. 相似文献
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Zakiyah Nur Meili Handoyo Tri Kim Kyung-Min 《Journal of Crop Science and Biotechnology》2019,22(1):55-63
Journal of Crop Science and Biotechnology - In this research, we investigated genetic diversity of 21 rice genotypes (Oryza sativa L.) assessed using 38 decamer RAPD primers. A total of 405 bands... 相似文献
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The history of scientific forest management in Bangladesh datesback to the nineteenth century with defined forest policiesand laws. Due to various socio-economic and socio-politicalfactors, forest cover of the country reduced drastically andall such policy initiatives proved ineffective. Although traditionalforest management objectives covered a wide range from economicbenefit to ecological stability, these have never been attainedfully. Huge population and limited land area compelled policymakers to think about alternatives to traditional forest management.One alternative, social forestry, was introduced in Bangladeshin early 1980s and has proved to be extremely successful. Whiletraditional forest management resulted in a net loss of forestresource cover, social forestry on the other hand, is playinga vital role in the expansion of forest cover (40 387 ha ofnew forest cover and 48 420 km new strip plantation since themid-1980s) benefiting thousands of poor people. Results showthat during the last four years (20002003) more than23 000 individuals benefited from the final felling of differentsocial forestry plantations (woodlot, agroforestry and stripplantation). This generated a total income of US$ 5.6 millionfor the government and US$ 5.3 million for participants plusUS$ 1.2 million for the Tree Farming Fund a 10 per centdepository reserve to sustain the practice in the long run.Although average individual final returns (US$ 223 person1)are not so attractive, some people got about US$ 5000 to US$8500 from final felling, sufficient to improve their standardof living and social position. Despite the success so far achieved,social forestry in Bangladesh still suffers from various institutionaldeficiencies like organization, skilled manpower, legitimateusufruct rights, peoples' participation from policy to implementationand clear budgetary arrangements. Besides, until now the roleof relevant actors is not well defined in all the steps of socialforestry practice in Bangladesh. Unless the participants aregiven clear legitimate usufruct rights, they will remain scepticaltowards this programme. They should have good and meaningfulaccess from planning to implementation. In the context of institutionaldevelopment, there are governmental policy guidelines and a20-year Master Plan for Bangladesh. Although some steps havebeen partially completed, there is still much to do to complywith forest policy guidelines and the Master Plan. It is shownthat in the last seven years (1995/962001/2002) onlyUS$ 15.41 million a1 has actually been spent againstan allocated sum of US$ 68.37 million a1. Therefore,if the intention is to institutionalize social forestry in Bangladesh,government and policy makers should actively come forward. Otherwisethe full potential of social forestry in Bangladesh will notbecome a reality. 相似文献
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María?C.?Mateo-SánchezEmail author Aitor?Gastón Carlos?Ciudad Juan?I.?García-Vi?as Jorge?Cuevas César?López-Leiva Alfredo?Fernández-Landa Nur?Algeet-Abarquero Miguel?Marchamalo Marie-Josée?Fortin Santiago?Saura 《Landscape Ecology》2016,31(6):1261-1276