9,214 research outputs found
Read Operators and their Expressiveness in Process Algebras
We study two different ways to enhance PAFAS, a process algebra for modelling
asynchronous timed concurrent systems, with non-blocking reading actions. We
first add reading in the form of a read-action prefix operator. This operator
is very flexible, but its somewhat complex semantics requires two types of
transition relations. We also present a read-set prefix operator with a simpler
semantics, but with syntactic restrictions. We discuss the expressiveness of
read prefixes; in particular, we compare them to read-arcs in Petri nets and
justify the simple semantics of the second variant by showing that its
processes can be translated into processes of the first with timed-bisimilar
behaviour. It is still an open problem whether the first algebra is more
expressive than the second; we give a number of laws that are interesting in
their own right, and can help to find a backward translation.Comment: In Proceedings EXPRESS 2011, arXiv:1108.407
Possible Implication of Red Blood Cells in the Prothrombotic Risk in Early Rheumatoid Arthritis
Rheumatoid arthritis (RA) is an autoimmune inflammatory disease that can be considered as a prothrombotic state1. A great number of studies have investigated the possible role of reactive oxygen species (ROS) in the etiology and pathogenesis of this disease. The presence of large amounts of superoxide radicals and hydrogen peroxide produced by activated neutrophils has been reported in the synovial fluid of patients with RA. This may cause lipid peroxidation that yields a wide variety of end products, including malondialdehyde (MDA), a known marker of oxidative stress. These products are therefore transported from the synovial fluid to the blood circulation system2. Considering that elevated levels of MDA have been observed in the blood plasma of patients with RA2, the aim of this pilot study was to investigate whether the elevated levels of plasmatic MDA could be associated with a modification of the total antioxidant capacity (TAC) of blood plasma that is usually indicative of a âsystemicâ oxidative imbalance3. In addition, in view of their activity as redox effectors or scavengers4, as well as determinants of thrombus formation5, we evaluated red blood cell (RBC) features in terms of their redox state and lifespan marker molecules
Recommender systems fairness evaluation via generalized cross entropy
Fairness in recommender systems has been considered with respect
to sensitive attributes of users (e.g., gender, race) or items (e.g., revenue
in a multistakeholder setting). Regardless, the concept has been
commonly interpreted as some form of equality â i.e., the degree to
which the system is meeting the information needs of all its users in
an equal sense. In this paper, we argue that fairness in recommender
systems does not necessarily imply equality, but instead it should
consider a distribution of resources based on merits and needs.We
present a probabilistic framework based ongeneralized cross entropy
to evaluate fairness of recommender systems under this perspective,
wherewe showthat the proposed framework is flexible and explanatory
by allowing to incorporate domain knowledge (through an ideal
fair distribution) that can help to understand which item or user aspects
a recommendation algorithm is over- or under-representing.
Results on two real-world datasets show the merits of the proposed
evaluation framework both in terms of user and item fairnessThis work was supported in part by the Center for Intelligent Information
Retrieval and in part by project TIN2016-80630-P (MINECO
Dolphin Morbillivirus Associated with a Mass Stranding of Sperm Whales, Italy
In September 2014, 7 sperm whales stranded along the Adriatic Italian coastlines. Postmortem investigations on 3 dead females dead and in 1 fetus harbored by the largest one revealed molecular and immunoistochemical evidences of dolphin morbillivirus infection. A possible role of the virus in the stranding event was considered
Draft Genome of Shewanella frigidimarina Ag06-30, a Marine Bacterium Isolated from Potter Peninsula, King George Island, Antarctica
We present the draft genome of Shewanella frigidimarina Ag06-30, a marine bacterium from King George Island, Antarctica,which encodes the carbapenemase SFP-1. The assembly contains 4,799,218 bp (GC content 41.24%). This strain harbors severalmobile genetic elements that provide insight into lateral gene transfer and bacterial plasticity and evolution.Fil: Parmeciano Di Noto, Gisela Paula. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: VĂĄzquez, Susana Claudia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de NanobiotecnologĂa. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Instituto de NanobiotecnologĂa; ArgentinaFil: MacCormack, Walter P.. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de NanobiotecnologĂa. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Instituto de NanobiotecnologĂa; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. DirecciĂłn Nacional del AntĂĄrtico. Instituto AntĂĄrtico Argentino; ArgentinaFil: Iriarte, AndrĂ©s. Universidad de la RepĂșblica; Uruguay. Instituto de Investigaciones BiolĂłgicas ; UruguayFil: Quiroga, Cecilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; Argentin
Sind unsere KĂŒhe fĂŒr die Weide noch geeignet?
In vielen LĂ€ndern ist in den letzten Jahrzehnten ein deutlicher Anstieg der Milchleistung bei KĂŒhen in der Milchviehhaltung zu beobachten. Gleichzeitig ging bei steigendem Kraftfuttereinsatz der Weidegrasanteil in den Milchviehrationen zurĂŒck und wurden die KĂŒhe auch gröĂer und schwerer. Fasst man die Literaturergebnisse zur Eignung von Hochleistungstieren fĂŒr die (konsequente) Weidehaltung zusammen, dann zeigt sich folgendes Bild:
âą Die tĂ€gliche Weidefutteraufnahme ist im Gegensatz zur Stallhaltung mit 15â20 kg T pro Tier stĂ€rker begrenzt. Als Ursachen dafĂŒr werden die begrenzte Fresszeit, Bissfrequenz und Bissanzahl diskutiert.
âą Hochleistungstiere mobilisieren zu Laktationsbeginn im Vergleich zu niedrig leistenden KĂŒhen ĂŒber einen lĂ€ngeren Zeitraum und auch deutlich stĂ€rker Körperreserven.
âą Mit steigender Einzeltierleistung muss bei Weidehaltung mit einer stĂ€rkeren Stoffwechselbelastung (NĂ€hrstoffmobilisation, erhöhte Stoffwechselrate, Hitzestress, etc.) gerechnet werden. Diese kann auch zu einer Verschlechterung der Fruchtbarkeitsergebnisse und Nutzungsdauer fĂŒhren.
âą Wenn hohe Einzeltierleistungen mit gröĂeren und schwereren KĂŒhen verbunden sind, dann ist von stĂ€rkeren TrittschĂ€den auf den Weiden auszugehen.
In Ăsterreich greift ein GroĂteil der Weidebetriebe auf Stunden- oder Halbtagsweidehaltung mit entsprechend hoher BeifĂŒtterung zurĂŒck. DarĂŒber hinaus ist die saisonale Abkalbung nicht ĂŒblich. Bei diesen eingeschrĂ€nkten (Weide-) Systemen ist daher (noch) nicht zu erwarten, dass die derzeitigen gezĂŒchteten Kuhtypen nicht mehr weidetauglich sind. Je stĂ€rker jedoch âLow-Inputâ Strategien am Milchviehbetrieb umgesetzt werden, desto weniger geeignet dĂŒrften dafĂŒr KĂŒhe mit hohen Laktations(einsatz)leistungen sein. GrundsĂ€tzlich kann extensiver wirtschaftenden Betrieben bzw. biologisch wirtschaftenden Betrieben empfohlen werden, bei der Zuchttierauswahl verstĂ€rktes Augenmerk auf die Fitnessmerkmale zu legen. Bei zunehmender Differenzierung der Leistungs- und FĂŒtterungsbedingungen zwischen den Betriebssystemen ist nĂ€mlich zu erwarten, dass die unter intensiveren Bedingungen ausgelesen Tiere nicht mehr automatisch auch die besten KĂŒhe fĂŒr extensive FĂŒtterungsbedingungen (Genotyp-Umwelt-Interaktion) sind. Stellt man einen Vergleich der Zuchtwerte der eingesetzten Zuchtstiere auf biologisch und konventionell wirtschaftenden Betrieben an, dann zeigen sich nĂ€mlich noch keine wesentlichen Unterschiede. Bio-Betriebe greifen (noch) nicht stĂ€rker als die konventionellen Berufskollegen/innen auf Tiere mit hohen Fitnesszuchtwerten zurĂŒck (FĂŒrst 2006)
Energiepflanzenproduktion in biologischen Marktfruchtbetrieben
On organic crop farms mobile nitrogen sources are scarce. One possible source can be degassed biomass from fermented energy crops produced on organic farms. This study analyses the effects of an investment in a cooperative biogas plant on the production program and the net farm income using a linear planning model. The production of green electricity from biogas yields in a higher net farm income. Alfalfa grass is a more efficient energy crop than maize in organic farms. Fewer legumes and more cash crops are produced. The yearly labour requirement rises due to the production of energy crops, operation of the biogas plant and spreading the degassed biomass
Valuing environmental education as a cultural ecosystem service at Hudson River Park
Author Posting. © The Author(s), 2018. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Ecosystem Services 31C (2018): 387-394, doi:10.1016/j.ecoser.2018.03.005.The Hudson River and its estuary is once again an ecologically, economically, and culturally functional component of New York Cityâs natural environment. The estuary's cultural significance may derive largely from environmental education, including marine science programs for the public. These programs are understood as âculturalâ ecosystem services but are rarely evaluated in economic terms. We estimated the economic value of the Hudson River Parkâs environmental education programs. We compiled data on visits by schools and summer camps from 32 New York City school districts to the Park during the years 2014 and 2015. A âtravel costâ approach was adapted from the field of environmental economics to estimate the value of education in this context. A smallâbut conservativeâestimate of the Parkâs annual education program benefits ranged between 25,500, implying an average capitalized value on the order of $0.6 million. Importantly, organizations in districts with high proportions of minority students or English language learners were found to be more likely to participate in the Parkâs programs. The results provide an optimistic view of the benefits of environmental education focused on urban estuaries, through which a growing understanding of ecological systems could lead to future environmental improvements.We thank the Hudson River Foundation and Woods Hole Oceanographic Institutionâs Summer Student Fellow program for financial support
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