359 research outputs found

    Identifikasi Parasit Pada Ikan Kuwe (Caranx spp) yang di Budidayakan di Keramba Jaring Apung Desa Talengen

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    Penelitian ini bertujuan untuk mengidentifikasi jenis parasit pada ikan kuwe (caranx spp) yang dibudidayakan di keramba jaring apung Desa Talengen. Penelitian ini dilaksanakan dengan mengambil sampel ikan kuwe secara acak di keramba jaring apung Desa Talengen dan pemeriksaan sampel dilakukan di Laboratorium Stasiun Karantina Ikan Kelas II Tahuna. Sampel ikan berjumlah 20 ekor. Hasil penelitian menunjukan 7 jenis parasit yang digolongkan dalam (2) dua jenis Protozoa : Trichodina sp dan Chilodonella sp; (1) satu jenis cacing bulat Nemathelminthes : Camallanus sp; (3) tiga cacing pipih Platyhelminthes : Hexostoma sp, Stephanostomum sp dan Scolex sp; (1) satu jenis parasit Arthropoda : Ergasilus sp

    Pengujian Kuat Lentur Kayu Profil Tersusun Bentuk Kotak

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    Kayu sebagai bahan bangunan mempunyai kelebihan dibanding bahan bangunan lainnya, tersedia hampir diseluruh dunia yang mudah diperoleh dalam berbagai bentuk dan ukuran. Namun, kayu solid sudah sangat susah ditemukan dengan ukuran yang diinginkan. Sehingga dibuatlah inovasi balok tersusun dengan cara menggabungkan beberapa kayu untuk mendapatkan variasi ukuran balok kayu yang diinginkan dan dibutuhkan. Dengan menggabungkan kayu menjadi balok tersusun digunakan berbagai macam jenis sambungan.Penelitian ini bertujuan untuk mengetahui sifat karakterisik kayu dengan pengujian modulus elastisitas dan kekuatan lentur balok tersusun kayu. Balok tersusun dengan dimensi 130 mm x 150 mm x 1000 mm dengan ukuran paku 2 inch dan variasi jarak paku 3 cm, 6 cm, dan 9 cm, dengan sistem kampuh mendatar dan kampuh tegak dibuat untuk mengetahui kekuatan balok tersusun mana yang lebih kuat dan lebih efisien. Pengujian dilakukan dengan parameter SNI (Standar Nasional Indonesia).Hasil penelitian menyatakan bahwa mutu kayu ditentukan oleh modulus elastisitas. Dalam hasil didapatkan bahwa kayu cempaka yang digunakan diperoleh hasil nilai E7, E8, E9, E10. Kuat lentur kayu didapat bahwa kampuh tegak memiliki kekuatan lentur yang lebih kuat dengan nilai 44,918 kN, 47,009 kN, 50,342 kN, dibandingkan dengan kampuh mendatar dengan nilai 44,061 kN, 43,339 kN, 32,505 kN. Penelitian ini juga menunjukkan bahwa kampuh tegak dengan jarak 9 cm mempunyai kekuatan yang lebih kuat. Kekuatan paku tidak dilihat dan ditentukan oleh jumlah paku

    The Value of Sharing Information: A Neural Account of Information Transmission

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    Humans routinely share information with one another. What drives this behavior? We used neuroimaging to test an account of information selection and sharing that emphasizes inherent reward in self-reflection and connecting with other people. Participants underwent functional MRI while they considered personally reading and sharing New York Times articles. Activity in neural regions involved in positive valuation, self-related processing, and taking the perspective of others was significantly associated with decisions to select and share articles, and scaled with preferences to do so. Activity in all three sets of regions was greater when participants considered sharing articles with other people rather than selecting articles to read themselves. The findings suggest that people may consider value not only to themselves but also to others even when selecting news articles to consume personally. Further, sharing heightens activity in these pathways, in line with our proposal that humans derive value from self-reflection and connecting to others via sharing

    Adjustment of Daily Activities: the Influence of Smartphone Adoption on the Travel Pattern of Mobile Professionals in the Greater Jakarta Area

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    The swift augmentation in the adoption of smartphones, the gadget that resulted from the convergence of Information and Communication Technology (ICT), potentially transforms people\u27s life in myriad dimensions. One potential change induced by smartphones, is how people restructure their daily agenda and consecutively influence their travel pattern. To understand it, this study theoretically reviews mobile professional work, smartphone adoption, and how people conduct their mobile interaction, planning and execution of daily activities. Mobile professionals, the cohort of professionals that spend more than 20% of their total working time moving around out of their work environment; they are important beneficiaries of smartphones and have been chosen as the target of this study. Empirical results of mobile professionals´ experiences in the Greater Jakarta Area are presented at this juncture. Furthermore, their adjustment of activities as a dynamic response to receiving extensive information via smartphones is also analysed. The results indicate that there is a strong adjustment of daily activities by mobile professionals. Through those changes, the transformation of daily travel patterns related to the activity is also brought about by the use of this high-end ICT contrivance

    Macro-Climatic Distribution Limits Show Both Niche Expansion and Niche Specialization among C4 Panicoids

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    Grasses are ancestrally tropical understory species whose current dominance in warm open habitats is linked to the evolution of C4 photosynthesis. C4 grasses maintain high rates of photosynthesis in warm and water stressed environments, and the syndrome is considered to induce niche shifts into these habitats while adaptation to cold ones may be compromised. Global biogeographic analyses of C4 grasses have, however, concentrated on diversity patterns, while paying little attention to distributional limits. Using phylogenetic contrast analyses, we compared macro-climatic distribution limits among ~1300 grasses from the subfamily Panicoideae, which includes 4/5 of the known photosynthetic transitions in grasses. We explored whether evolution of C4 photosynthesis correlates with niche expansions, niche changes, or stasis at subfamily level and within the two tribes Paniceae and Paspaleae. We compared the climatic extremes of growing season temperatures, aridity, and mean temperatures of the coldest months. We found support for all the known biogeographic distribution patterns of C4 species, these patterns were, however, formed both by niche expansion and niche changes. The only ubiquitous response to a change in the photosynthetic pathway within Panicoideae was a niche expansion of the C4 species into regions with higher growing season temperatures, but without a withdrawal from the inherited climate niche. Other patterns varied among the tribes, as macro-climatic niche evolution in the American tribe Paspaleae differed from the pattern supported in the globally distributed tribe Paniceae and at family level.Fil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Biganzoli, Fernando. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Métodos Cuantitativos y Sistemas de Información; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bena, María Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Godoy Bürki, Ana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Reinheimer, Renata. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin

    Evaluation of continuous beam rescanning versus pulsed beam in pencil beam scanned proton therapy for lung tumours

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    The treatment of moving targets with pencil beam scanned proton therapy (PBS-PT) may rely on rescanning strategies to smooth out motion induced dosimetric disturbances. PBS-PT machines, such as Proteus (R) Plus (PPlus) and Proteus (R) One (POne), deliver a continuous or a pulsed beam, respectively. In PPlus, scaled (or no) rescanning can be applied, while POne implies intrinsic 'rescanning' due to its pulsed delivery. We investigated the efficacy of these PBS-PT delivery types for the treatment of lung tumours. In general, clinically acceptable plans were achieved, and PPlus and POne showed similar effectiveness

    Genome biogeography reveals the intraspecific spread of adaptive mutations for a complex trait

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    Physiological novelties are often studied at macro-evolutionary scales such that their micro-evolutionary origins remain poorly understood. Here, we test the hypothesis that key components of a complex trait can evolve in isolation and later be combined by gene flow. We use C4 photosynthesis as a study system, a derived physiology that increases plant productivity in warm, dry conditions. The grass Alloteropsis semialata includes C4 and non-C4 genotypes, with some populations using laterally-acquired C4 -adaptive loci, providing an outstanding system to track the spread of novel adaptive mutations. Using genome data from C4 and non-C4 A. semialata individuals spanning the species' range, we infer and date past migrations of different parts of the genome. Our results show that photosynthetic types initially diverged in isolated populations, where key C4 components were acquired. However, rare but recurrent subsequent gene flow allowed the spread of adaptive loci across genetic pools. Indeed, laterally-acquired genes for key C4 functions were rapidly passed between populations with otherwise distinct gene pools. Thus, our intraspecific study of C4 -related genomic variation indicates that components of adaptive traits can evolve separately and later be combined through secondary gene flow, leading to the assembly and optimization of evolutionary innovations. This article is protected by copyright. All rights reserved

    Production and ecosystem structure in cold‐core vs. warm‐core eddies: Implications for the zooplankton isoscape and rock lobster larvae

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    Anticyclonic (warm-core) mesoscale eddies (WCEs) in the Eastern Indian Ocean carry higher surface chlorophyll signatures than cyclonic (cold-core) eddies (CCEs). Paradoxically, WCEs host rock lobster larvae (phyllosomas) with lower lipid stores and protein reserves than phyllosomas in CCEs, suggesting a poorer nutritional status. We assess primary productivity and zooplankton isotopic data from eight eddies across four research voyages (2003–2011) to determine how this contradiction might occur. We find that WCEs and CCEs are equally productive per unit chlorophyll a, but depth-integrated primary production (PP) is greater in eddies with shallower mixed layers (MLs), especially in CCEs. MLs tend to be shallower in CCEs than in WCEs because the pycnocline is closer to the surface. This, in combination with stronger stratification in CCE euphotic zones than those of WCEs, supports greater flagellate and dinoflagellate populations in CCEs. These phytoplankton provide high-quality nutrition for zooplankton, which feed on average ~ 0.6 trophic level lower in CCEs with the shallowest MLs, accumulating high lipid stores. Conversely, WCEs have, on average, ~ 70 m deeper MLs than CCEs, and host a phytoplankton community with more diatoms. Diatoms provide lower quality food for zooplankton, and zooplankton lipid stores in WCEs decline with trophic level, and possibly, with time after initial (or seasonal) nutrient injection. As a result, phyllosomas in CCEs have higher energy and lipid content than those in warm-core eddies. The resolution of the paradox, therefore, is that the higher surface chlorophyll signatures of WCEs are not representative of the nutritional value of the prey field of the phyllosoma. We also conclude that interannual variations of mixed layer depth occur at a regional scale, controlling PP

    Erythritol and xylitol differentially impact brain networks involved in appetite regulation in healthy volunteers

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    Background: There is a growing consensus that sugar consumption should be reduced and the naturally occurring, low-calorie sweeteners xylitol and erythritol are gaining popularity as substitutes, but their effect on brain circuitry regulating appetite is unknown. Aim: The study’s objective was to examine the effects of the two sweeteners on cerebral blood flow (rCBF) and resting functional connectivity in brain networks involved in appetite regulation, and test whether these effects are related to gut hormone release. Methods: The study was performed as a randomized, double-blind, placebo-controlled, cross-over trial. Twenty volunteers received intragastric (ig) loads of 50g xylitol, 75g erythritol, 75g glucose dissolved in 300mL tap water or 300mL tap water. Resting perfusion and blood oxygenation level-dependent data were acquired to assess rCBF and functional connectivity. Blood samples were collected for determination of CCK, PYY, insulin and glucose. Results: We found: (i) xylitol, but not erythritol, increased rCBF in the hypothalamus, whereas glucose had the opposite effect; (ii) graph analysis of resting functional connectivity revealed a complex pattern of similarities and differences in brain network properties following xylitol, erythritol, and glucose; (iii) erythritol and xylitol induced a rise in CCK and PYY, (iv) erythritol had no and xylitol only minimal effects on glucose and insulin. Conclusion: Xylitol and erythritol have a unique combination of properties: no calories, virtually no effect on glucose and insulin while promoting the release of gut hormones, and impacting appetite-regulating neurocircuitry consisting of both similarities and differences with glucose
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