12,609 research outputs found
Ecosystem Viable Yields
The World Summit on Sustainable Development (Johannesburg, 2002) encouraged
the application of the ecosystem approach by 2010. However, at the same Summit,
the signatory States undertook to restore and exploit their stocks at maximum
sustainable yield (MSY), a concept and practice without ecosystemic dimension,
since MSY is computed species by species, on the basis of a monospecific model.
Acknowledging this gap, we propose a definition of "ecosystem viable yields"
(EVY) as yields compatible i) with guaranteed biological safety levels for all
time and ii) with an ecosystem dynamics. To the difference of MSY, this notion
is not based on equilibrium, but on viability theory, which offers advantages
for robustness. For a generic class of multispecies models with harvesting, we
provide explicit expressions for the EVY. We apply our approach to the
anchovy--hake couple in the Peruvian upwelling ecosystem
Unconventional Therapy on Headache from Anatomy and Physiology Standpoint
This article discusses applied pharmacotherapy related to headaches and Gout. Headache is one of the frequently reported subjective complaints. Based on the causes, they are classified as primary headaches and secondary headaches. The aim of this paper is that students can know the definition of headache, know the classification of panic pain, know the anatomy and physiology of headache, know the prevention of headaches and adjunctive therapy and know the management for headaches
The early stages of heart development: insights from chicken embryos
The heart is the first functioning organ in the developing embryo and the detailed understanding of the molecular and cellular mechanisms involved in its formation provides insights into congenital malformations affecting its function and therefore the survival of the organism. Because many developmental mechanisms are highly conserved, it is possible to extrapolate from observations made in invertebrate and vertebrate model organisms to human. This review will highlight the contributions made through studying heart development in avian embryos, particularly the chicken. The major advantage of chick embryos is their accessibility for surgical manipulations and functional interference approaches, both gain- and loss-of-function. In addition to experiments performed in ovo, the dissection of tissues for ex vivo culture, genomic or biochemical approaches, is straightforward. Furthermore, embryos can be cultured for time-lapse imaging, which enables tracking of fluorescently labeled cells and detailed analyses of tissue morphogenesis. Owing to these features, investigations in chick embryos have led to important discoveries, often complementing genetic studies in mouse and zebrafish. As well as including some historical aspects, we cover here some of the crucial advances made in understanding of early heart development using the chicken model
The numerical solution of the Navier-Stokes equations for laminar incompressible flow past a paraboloid of revolution
A numerical method is presented for the solution of the Navier-Stokes equations for flow past a paraboloid of revolution. The flow field has been computed for a large range of Reynolds numbers. Results are presented for the skinfriction and the pressure together with their respective drag coefficients. The total drag has been checked by means of an application of the momentum theorem.
Friend or Beau?
We’ve seen it in romantic comedies, sitcoms and even on this season of “The Bachelor.” Friends of the opposite sex either become Mr. and Mrs. Chandler Bing or are sent home at the Rose Ceremony. But what about in between? Can friends that move ahead romantically go back to being just friends
Fermi Large Area Telescope observations of GRB 110625A
Gamma-ray bursts (GRBs) that emit photons at GeV energies form a small but
significant population of GRBs. However, the number of GRBs whose GeV-emitting
period is simultaneously observed in X-rays remains small. We report gamma-ray
observations of GRB 110625A using Fermi's Large Area Telescope (LAT) in the
energy range 100 MeV to 20 GeV. Gamma-ray emission at these energies was
clearly detected using data taken between 180s and 580s after the burst, an
epoch after the prompt emission phase. The GeV light curve differs from a
simple power-law decay, and probably consists of two emission periods.
Simultaneous Swift/XRT observations did not show flaring behaviors as in the
case of GRB 100728A. We discuss the possibility that the GeV emission is the
synchrotron self-Compton radiation of underlying ultraviolet flares.Comment: 6 pages, 3 figures, 1 table; accepted for publication in the ApJ on
May 31, 201
Expression kinetics and innate immune response after electroporation and LNP-mediated delivery of a self-amplifying mRNA in the skin
In this work, we studied the expression kinetics and innate immune response of a self-amplifying mRNA (sa-RNA) after electroporation and lipid-nanoparticle (LNP)-mediated delivery in the skin of mice. Intradermal electroporation of the sa-RNA resulted in a plateau-shaped expression, with the plateau between day 3 and day 10. The overall protein expression of sa-RNA was significantly higher than that obtained after electroporation of plasmid DNA (pDNA) or non-replication mRNAs. Moreover, using IFN-beta reporter mice, we elucidated that intradermal electroporation of sa-RNA induced a short-lived moderate innate immune response, which did not affect the expression of the sa-RNA. A completely different expression profile and innate immune response were observed when LNPs were used. The expression peaked 24 h after intradermal injection of sa-RNA-LNPs and subsequently showed a sharp drop. This drop might be explained by a translational blockage caused by the strong innate immune response that we observed in IFN-beta reporter mice shortly (4 h) after intradermal injection of sa-RNA-LNPs. A final interesting observation was the capacity of sa-RNA-LNPs to transfect the draining lymph nodes after intradermal injection
Aurora Credit Services, a Minnesota corporation, on behalf of itself and all other shareholders of Liberty West Development, a corporation, v. Liberty West Development, a Utah corporation, XM INTERNATIONAL, a Utah limited liability company, and DENNIS W. GAY, an individual : Reply Brief
APPEAL COURT FROM JUDGMENT OF IN AND FOR JUDGE L. SALT THIRD LAKE A. DEVER DISTRICT COUNTY
Microchamber Cultures of Bladder Cancer: A Platform for Characterizing Drug Responsiveness and Resistance in PDX and Primary Cancer Cells.
Precision cancer medicine seeks to target the underlying genetic alterations of cancer; however, it has been challenging to use genetic profiles of individual patients in identifying the most appropriate anti-cancer drugs. This spurred the development of patient avatars; for example, patient-derived xenografts (PDXs) established in mice and used for drug exposure studies. However, PDXs are associated with high cost, long development time and low efficiency of engraftment. Herein we explored the use of microfluidic devices or microchambers as simple and low-cost means of maintaining bladder cancer cells over extended periods of times in order to study patterns of drug responsiveness and resistance. When placed into 75 µm tall microfluidic chambers, cancer cells grew as ellipsoids reaching millimeter-scale dimeters over the course of 30 days in culture. We cultured three PDX and three clinical patient specimens with 100% success rate. The turn-around time for a typical efficacy study using microchambers was less than 10 days. Importantly, PDX-derived ellipsoids in microchambers retained patterns of drug responsiveness and resistance observed in PDX mice and also exhibited in vivo-like heterogeneity of tumor responses. Overall, this study establishes microfluidic cultures of difficult-to-maintain primary cancer cells as a useful tool for precision cancer medicine
Viability Kernel for Ecosystem Management Models
We consider sustainable management issues formulated within the framework of
control theory. The problem is one of controlling a discrete--time dynamical
system (e.g. population model) in the presence of state and control
constraints, representing conflicting economic and ecological issues for
instance. The viability kernel is known to play a basic role for the analysis
of such problems and the design of viable control feedbacks, but its
computation is not an easy task in general. We study the viability of nonlinear
generic ecosystem models under preservation and production constraints. Under
simple conditions on the growth rates at the boundary constraints, we provide
an explicit description of the viability kernel. A numerical illustration is
given for the hake--anchovy couple in the Peruvian upwelling ecosystem
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