201 research outputs found
Identifikasi Keanekaragaman Jenis Burung dan Kearifan Tradisional Masyarakat dalam Upaya Konservasi di Pulau Rambut Kepulauan Seribu
Tujuan penelitian ini adalah untuk: (1) Menganalisis keanekaragaman jenis burung di Pulau Rambut Kepulauan Seribu menggunakan metode encounter rates (tingkat pertemuan) yaitu pengamatan langsung dengan cara menjelajah dan menghitung setiap individu yang ditemui, (2) Menjelaskan bentuk kearifan tradisional masyarakat Pulau Untung Jawa Kepulauan Seribu, dan (3) Menjelaskan ancaman terhadap kearifan serta menganalisis cara menangkal ancaman dalam upaya melestarikan burung. Pencarian data menggunakan observasi langsung berupa eksplorasi dan wawancara pada narasumber yang dapat dipercaya. Pengamatan dilakukan dengan teropong binokuler merk carton dengan ukuran 8 x 30 tipe 430 FT/1000 YDS made in Japan. Setiap burung yang dijumpai diperhatikan ukuran, warna, dan suaranya sera ciri-ciri khasnya, kemudian diidentifikasi. Masyarakat Pulau Untung Jawa menganggap burung yang ada di Pulau Rambut merupakan anugerah dan berkah yang harus dilestarikan. Keanekaragaman jenis burung di Pulau Rambut Kepulauan Seribu cukup tinggi yaitu ditunjukkan dengan 24 jenis burung. Adanya aktivitas masyarakat Pulau Untung Jawa diduga memberikan pengaruh terhadap keanekaragaman jenis burung yang terdapat di Pulau rambut Kepulauan Seribu
Sound and complete axiomatizations of coalgebraic language equivalence
Coalgebras provide a uniform framework to study dynamical systems, including
several types of automata. In this paper, we make use of the coalgebraic view
on systems to investigate, in a uniform way, under which conditions calculi
that are sound and complete with respect to behavioral equivalence can be
extended to a coarser coalgebraic language equivalence, which arises from a
generalised powerset construction that determinises coalgebras. We show that
soundness and completeness are established by proving that expressions modulo
axioms of a calculus form the rational fixpoint of the given type functor. Our
main result is that the rational fixpoint of the functor , where is a
monad describing the branching of the systems (e.g. non-determinism, weights,
probability etc.), has as a quotient the rational fixpoint of the
"determinised" type functor , a lifting of to the category of
-algebras. We apply our framework to the concrete example of weighted
automata, for which we present a new sound and complete calculus for weighted
language equivalence. As a special case, we obtain non-deterministic automata,
where we recover Rabinovich's sound and complete calculus for language
equivalence.Comment: Corrected version of published journal articl
Méthode d'évaluation de l'action de conseil en irrigation IRRIPARC en régions Nord-Pas-de-Calais et Picardie
Parmi les nombreuses actions de conseil en irrigation dĂ©veloppĂ©es en France, trop peu d'entre elles sont Ă©valuĂ©es pour apprĂ©cier leur impact sur les pratiques d'irrigation et les bĂ©nĂ©fices pour la ressource. Dans cet article, nous proposons une mĂ©thode d'Ă©valuation de l'une d'entre elles, sur l'Ă©tude d'un cas concret : l'action IRRIPARC. Dans les rĂ©gions Nord-Pas-de-Calais et Picardie, des fiches de rĂ©glages de canons enrouleurs ont Ă©tĂ© diffusĂ©es aux agriculteurs, pour limiter les effets du vent sur l'uniformitĂ© de la rĂ©partition de l'eau d'irrigation. La mĂ©thode d'Ă©valuation proposĂ©e repose sur l'Ă©tude de trois critĂšres : l'efficacitĂ©, la pertinence et la cohĂ©rence de l'action. La collecte des donnĂ©es se fait par enquĂȘtes quantitatives et qualitatives auprĂšs de diffĂ©rents acteurs : les agriculteurs, public cible de l'action, et les partenaires impliquĂ©s dans l'action IRRIPARC. L'analyse dĂ©bouche sur des perspectives d'Ă©volution et fournit des recommandations pour l'action. / Several technical support actions in irrigation have been carried out in France. However, very few have been evaluated to determine their actual impact on irrigation practices and their water saving benefits. In this paper, an assessment method of a technical support action is presented on a concrete case: the IRRIPARC action. The action was carried in the Nord Pas-de-Calais region of France. It aims at providing to farmers technical forms to help them to set their irrigation guns according to the wind speed in order to improve water distribution uniformity. The method depends on three criteria based on the effectiveness, the relevance and the consistency of the action. The data have been collected through quantitative and qualitative enquiries to different stakeholders: farmers to which the action was intended, and other partners which were involved in the action. The analysis results in evolution perspective of IRRIPARC action
Tropical sea surface temperatures for the past four centuries reconstructed from coral archives
Most annually resolved climate reconstructions of the Common Era are based on terrestrial data, making it a challenge to independently assess how recent climate changes have affected the oceans. Here as part of the Past Global Changes Ocean2K project, we present four regionally calibrated and validated reconstructions of sea surface temperatures in the tropics, based on 57 published and publicly archived marine paleoclimate data sets derived exclusively from tropical coral archives. Validation exercises suggest that our reconstructions are interpretable for much of the past 400 years, depending on the availability of paleoclimate data within, and the reconstruction validation statistics for, each target region. Analysis of the trends in the data suggests that the Indian, western Pacific, and western Atlantic Ocean regions were cooling until modern warming began around the 1830s. The early 1800s were an exceptionally cool period in the Indo-Pacific region, likely due to multiple large tropical volcanic eruptions occurring in the early nineteenth century. Decadal-scale variability is a quasi-persistent feature of all basins. Twentieth century warming associated with greenhouse gas emissions is apparent in the Indian, West Pacific, and western Atlantic Oceans, but we find no evidence that either natural or anthropogenic forcings have altered El Ni ËnoâSouthern Oscillation-related variance in tropical sea surface temperatures. Our marine-based regional paleoclimate reconstructions serve as benchmarks against which terrestrial reconstructions as well as climate model simulations can be compared and as a basis for studying the processes by which the tropical oceans mediate climate variability and change
Autonomous and self-sustained circadian oscillators displayed in human islet cells
Aims/hypothesis: Following on from the emerging importance of the pancreas circadian clock on islet function and the development of type 2 diabetes in rodent models, we aimed to examine circadian gene expression in human islets. The oscillator properties were assessed in intact islets as well as in beta cells. Methods: We established a system for long-term bioluminescence recording in cultured human islets, employing lentivector gene delivery of the core clock gene Bmal1 (also known as Arntl)-luciferase reporter. Beta cells were stably labelled using a rat insulin2 promoter fluorescent construct. Single-islet/cell oscillation profiles were measured by combined bioluminescence-fluorescence time-lapse microscopy. Results: Human islets synchronised in vitro exhibited self-sustained circadian oscillations of Bmal1-luciferase expression at both the population and single-islet levels, with period lengths of 23.6 and 23.9h, respectively. Endogenous BMAL1 and CRY1 transcript expression was circadian in synchronised islets over 48h, and antiphasic to REV-ERBα (also known as NR1D1), PER1, PER2, PER3 and DBP transcript circadian profiles. HNF1A and PDX1 exhibited weak circadian oscillations, in phase with the REV-ERBα transcript. Dispersed islet cells were strongly oscillating as well, at population and single-cell levels. Importantly, beta and non-beta cells revealed oscillatory profiles that were well synchronised with each other. Conclusions/interpretation: We provide for the first time compelling evidence for high-amplitude cell-autonomous circadian oscillators displayed in human pancreatic islets and in dispersed human islet cells. Moreover, these clocks are synchronised between beta and non-beta cells in primary human islet cell culture
Spatial and temporal robustness of Sr/CaâSST calibrations in Red Sea corals : evidence for influence of mean annual temperature on calibration slopes
© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Paleoceanography and Paleoclimatology 33 (2018): 443-456, doi:10.1029/2017PA003276.Sr/Ca ratios recorded in the aragonite skeleton of massive coral colonies are commonly used to reconstruct seasonalâ to centennialâscale variability in sea surface temperature (SST). While the Sr/Ca paleothermometer is robust in individual colonies, Sr/CaâSST relationships between colonies vary, leading to questions regarding the utility of the proxy. We present biweeklyâresolution calibrations of Sr/Ca from five Porites spp. corals to satellite SST across 10° of latitude in the Red Sea to evaluate the Sr/Ca proxy across both spatial and temporal scales. SST is significantly correlated with coral Sr/Ca at each site, accounting for 69â84% of Sr/Ca variability (P âȘ 0.01). Intercolony variability in Sr/CaâSST sensitivities reveals a latitudinal trend, where calibration slopes become shallower with increasing mean annual temperature. Mean annual temperature is strongly correlated with the biweeklyâresolution calibration slopes across five Red Sea sites (r2 = 0.88, P = 0.05), while also correlating significantly to Sr/CaâSST slopes for 33 Porites corals from across the entire IndoâPacific region (r2 = 0.26, P < 0.01). Although interannual summer, winter, and mean annual calibrations for individual Red Sea colonies are inconsistently robust, combined multicoral calibrations are significant at summer (r2 = 0.53, P âȘ 0.01), winter (r2 = 0.62, P âȘ 0.01), and mean annual time scales (r2 = 0.79, P âȘ 0.01). Our multicoral, multisite study indicates that the Sr/Ca paleothermometer is accurate across both temporal and spatial scales in the Red Sea and also potentially explains for the first time variability in Sr/CaâSST calibration slopes across the IndoâPacific region. Our study provides strong evidence supporting the robustness of the coral Sr/Ca proxy for examining seasonal to multicentury variability in global climate phenomena.Singapore Ministry of Education;
National Research Foundation Singapore Grant Number: NRFFâ2012â03;
U.S. National Science Foundation Grant Number: OCEâ1031288;
King Abdullah University of Science and Technology Grant Numbers: USA 00002, KSA 0001
Autonomous and self-sustained circadian oscillators displayed in human islet cells
Aims/hypothesis: Following on from the emerging importance of the pancreas circadian clock on islet function and the development of type 2 diabetes in rodent models, we aimed to examine circadian gene expression in human islets. The oscillator properties were assessed in intact islets as well as in beta cells. Methods: We established a system for long-term bioluminescence recording in cultured human islets, employing lentivector gene delivery of the core clock gene Bmal1 (also known as Arntl)-luciferase reporter. Beta cells were stably labelled using a rat insulin2 promoter fluorescent construct. Single-islet/cell oscillation profiles were measured by combined bioluminescence-fluorescence time-lapse microscopy. Results: Human islets synchronised in vitro exhibited self-sustained circadian oscillations of Bmal1-luciferase expression at both the population and single-islet levels, with period lengths of 23.6 and 23.9h, respectively. Endogenous BMAL1 and CRY1 transcript expression was circadian in synchronised islets over 48h, and antiphasic to REV-ERBα (also known as NR1D1), PER1, PER2, PER3 and DBP transcript circadian profiles. HNF1A and PDX1 exhibited weak circadian oscillations, in phase with the REV-ERBα transcript. Dispersed islet cells were strongly oscillating as well, at population and single-cell levels. Importantly, beta and non-beta cells revealed oscillatory profiles that were well synchronised with each other. Conclusions/interpretation: We provide for the first time compelling evidence for high-amplitude cell-autonomous circadian oscillators displayed in human pancreatic islets and in dispersed human islet cells. Moreover, these clocks are synchronised between beta and non-beta cells in primary human islet cell culture
The Expectation Monad in Quantum Foundations
The expectation monad is introduced abstractly via two composable
adjunctions, but concretely captures measures. It turns out to sit in between
known monads: on the one hand the distribution and ultrafilter monad, and on
the other hand the continuation monad. This expectation monad is used in two
probabilistic analogues of fundamental results of Manes and Gelfand for the
ultrafilter monad: algebras of the expectation monad are convex compact
Hausdorff spaces, and are dually equivalent to so-called Banach effect
algebras. These structures capture states and effects in quantum foundations,
and also the duality between them. Moreover, the approach leads to a new
re-formulation of Gleason's theorem, expressing that effects on a Hilbert space
are free effect modules on projections, obtained via tensoring with the unit
interval.Comment: In Proceedings QPL 2011, arXiv:1210.029
ROBO2 is a stroma suppressor gene in the pancreas and acts via TGF-ÎČ signalling.
Whereas genomic aberrations in the SLIT-ROBO pathway are frequent in pancreatic ductal adenocarcinoma (PDAC), their function in the pancreas is unclear. Here we report that in pancreatitis and PDAC mouse models, epithelial Robo2 expression is lost while Robo1 expression becomes most prominent in the stroma. Cell cultures of mice with loss of epithelial Robo2 (Pdx1Cre;Robo2F/F) show increased activation of Robo1+ myofibroblasts and induction of TGF-ÎČ and Wnt pathways. During pancreatitis, Pdx1Cre;Robo2F/F mice present enhanced myofibroblast activation, collagen crosslinking, T-cell infiltration and tumorigenic immune markers. The TGF-ÎČ inhibitor galunisertib suppresses these effects. In PDACÂ patients, ROBO2 expression is overall low while ROBO1 is variably expressed in epithelium and high in stroma. ROBO2low;ROBO1high patients present the poorest survival. In conclusion, Robo2 acts non-autonomously as a stroma suppressor gene by restraining myofibroblast activation and T-cell infiltration. ROBO1/2 expression in PDAC patients may guide therapy with TGF-ÎČ inhibitors or other stroma /immune modulating agents
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