3,799 research outputs found
Hepatocyte growth factor stimulates neutrophil degranulation but not respiratory burst
Neutrophil function is regulated in part by cytokines with growth factor activities for different cell types. Hepatocyte growth factor (HGF) is a cytokine produced during injury to the liver and other organs. Neutrophils are numerous in such tissue injury sites and may be influenced by HGF. In the present study the effect of HGF on neutrophils was investigated. The data show that HGF at 1–10 ng/ml increased lysosomal enzyme release from both specific and azurophilic granules of cytochalasin-B treated neutrophils. The release of specific granule contents in response to N-formyl-methionyl-leucylphenylalanine was also increased by HGF. In contrast there were no significant effects of HGF on neutrophil respiratory burst, adherence or locomotion. It is concluded that HGF modulates neutrophil granule exocytosis
review of the social and environmental factors affecting the behavior and welfare of turkeys meleagris gallopavo
ABSTRACT In modern rearing systems, turkey producers often face economic losses due to increased aggression, feather pecking, cannibalism, leg disorders, or injuries among birds, which are also significant welfare issues. The main underlying causes appear to relate to rapid growth, flock size, density, poor environmental complexity, or lighting, which may be deficient in providing the birds with an adequate physical or social environment. To date, there is little information regarding the effect of these factors on turkey welfare. This knowledge is, however, essential to ensure the welfare of turkeys and to improve their quality of life, but may also be beneficial to industry, allowing better bird performance, improved carcass quality, and reduced mortality and condemnations. This paper reviews the available scientific literature related to the behavior of turkeys as influenced by the physical and social environment that may be relevant to advances toward turkey production systems that take welfare into consideration. We addressed the effects that factors such as density, group size, space availability, maturation, lightning, feeding, and transport may have over parameters that may be relevant to ensure welfare of turkeys. Available scientific studies were based in experimental environments and identified individual factors corresponding to particular welfare problems. Most of the studies aimed at finding optimal levels of rearing conditions that allow avoiding or decreasing most severe welfare issues. This paper discusses the importance of these factors for development of production environments that would be better suited from a welfare and economic point of view
Strong approximations of Brownian sheet by uniform transport processes.
Many years ago, Griego, Heath and Ruiz-Moncayo proved that it is possible to define realizations of a sequence of uniform transport processes that converges almost surely to the standard Brownian motion, uniformly on the unit time interval. In this paper we extend their results to the multi parameter case. We begin constructing a family of processes, starting from a set of independent standard Poisson processes, that has realizations that converge almost surely to the Brownian sheet, uniformly on the unit square. At the end the extension to the d-parameter Wiener processes is presented
Diatom flagellar genes and their expression during sexual reproduction in Leptocylindrus danicus
Background: Flagella have been lost in the vegetative phase of the diatom life cycle, but they are still present in male gametes of centric species, thereby representing a hallmark of sexual reproduction. This process, besides maintaining and creating new genetic diversity, in diatoms is also fundamental to restore the maximum cell size following its reduction during vegetative division. Nevertheless, sexual reproduction has been demonstrated in a limited number of diatom species, while our understanding of its different phases and of their genetic control is scarce. Results: In the transcriptome of Leptocylindrus danicus, a centric diatom widespread in the world's seas, we identified 22 transcripts related to the flagella development and confirmed synchronous overexpression of 6 flagellum-related genes during the male gamete formation process. These transcripts were mostly absent in the closely related species L. aporus, which does not have sexual reproduction. Among the 22 transcripts, L. danicus showed proteins that belong to the Intra Flagellar Transport (IFT) subcomplex B as well as IFT-A proteins, the latter previously thought to be absent in diatoms. The presence of flagellum-related proteins was also traced in the transcriptomes of several other centric species. Finally, phylogenetic reconstruction of the IFT172 and IFT88 proteins showed that their sequences are conserved across protist species and have evolved similarly to other phylogenetic marker genes. Conclusion: Our analysis describes for the first time the diatom flagellar gene set, which appears to be more complete and functional than previously reported based on the genome sequence of the model centric diatom, Thalassiosira pseudonana. This first recognition of the whole set of diatom flagellar genes and of their activation pattern paves the way to a wider recognition of the relevance of sexual reproduction in individual species and in the natural environment
An estimate of attributable cases of alzheimer disease and vascular dementia due to modifiable risk factors. the impact of primary prevention in europe and in italy
Background:
Up to 53.7% of all cases of dementia are assumed to be due to Alzheimer disease (AD), while 15.8% are considered to be due to vascular dementia (VaD). In Europe, about 3 million cases of AD could be due to 7 potentially modifiable risk factors: diabetes, midlife hypertension and/or obesity, physical inactivity, depression, smoking, and low educational level.
Aims:
To estimate the number of VaD cases in Europe and the number of AD and VaD cases in Italy attributable to these 7 potentially modifiable risk factors.
Methods:
Assuming the nonindependence of the 7 risk factors, the adjusted combined population attributable risk (PAR) was estimated for AD and VaD.
Results:
In Europe, adjusted combined PAR was 31.4% for AD and 37.8% for VaD. The total number of attributable cases was 3,033,000 for AD and 873,000 for VaD. In Italy, assuming a 20% reduction of the prevalence of each risk factor, adjusted combined PAR decreased from 45.2 to 38.9% for AD and from 53.1 to 46.6% for VaD, implying a 6.4 and 6.5% reduction in the prevalence of AD and VaD, respectively.
Conclusion:
A relevant reduction of AD and VaD cases in Europe and Italy could be obtained through primary prevention
Efficacy of intramuscular polysulfated glycosaminoglycan in a controlled study of equine carpitis
Twelve healthy horses were subject to the monoioidoacetate (MIA) carpitis model, which was allowed to develop for 7 days. The horses were then randomly divided into two groups. Group A (control) received an intramuscular injection of normal saline every 4 days for a total of seven injections while group B received 500 mg of a PSGAG (SYNTEX CSY36) intramuscularly every 4 days for seven treatments. Efficacy of the PSGAG was evaluated by three clinical outcomes: lameness score, carpal circumference and maximum carpal flexion. Clinical outcomes were measured on days -8 (previous to carpitis induction), 0 (previous to drug treatment), 7, 14, 21, 28 and 35. Areas under the curve clinical outcome as function of time were built and used as variables for the statistical analysis. There was less joint circumference enlargement and lameness and greater carpal flexion in PSGAG-treated horses compared with that in controls. The studied compound has demonstrated to be efficacious on the treatment of a chemically induced carpitis in horses.Fil: Verde, C.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Ferrante, M.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Simpson, M. I.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Babusci, M.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Broglia, G.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Landoni, Maria Fabiana. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata; Argentin
On the Feasibility of Malware Authorship Attribution
There are many occasions in which the security community is interested to
discover the authorship of malware binaries, either for digital forensics
analysis of malware corpora or for thwarting live threats of malware invasion.
Such a discovery of authorship might be possible due to stylistic features
inherent to software codes written by human programmers. Existing studies of
authorship attribution of general purpose software mainly focus on source code,
which is typically based on the style of programs and environment. However,
those features critically depend on the availability of the program source
code, which is usually not the case when dealing with malware binaries. Such
program binaries often do not retain many semantic or stylistic features due to
the compilation process. Therefore, authorship attribution in the domain of
malware binaries based on features and styles that will survive the compilation
process is challenging. This paper provides the state of the art in this
literature. Further, we analyze the features involved in those techniques. By
using a case study, we identify features that can survive the compilation
process. Finally, we analyze existing works on binary authorship attribution
and study their applicability to real malware binaries.Comment: FPS 201
Tracking the connection between disorder and energy landscape in glasses using geologically hyperaged amber
Fossil amber offers the unique opportunity of investigating an amorphous
material which has been exploring its energy landscape for more than 110 Myears
of natural aging. By applying different x-ray scattering methods to amber
before and after annealing the sample to erase its thermal history, we identify
a link between the potential energy landscape and the structural and
vibrational properties of glasses. We find that hyperaging induces a depletion
of the vibrational density of states in the THz region, also ruling the sound
dispersion and attenuation properties of the corresponding acoustic waves.
Critically, this is accompanied by a densification with structural implications
different in nature from that caused by hydrostatic compression. Our results,
rationalized within the framework of fluctuating elasticity theory, reveal how
upon approaching the bottom of the potential energy landscape (9% decrease in
the fictive temperature ) the elastic matrix becomes increasingly less
disordered (6%) and longer-range correlated (22%).Comment: 9 pages, 10 figure
New results on pushdown module checking with imperfect information
Model checking of open pushdown systems (OPD) w.r.t. standard branching
temporal logics (pushdown module checking or PMC) has been recently
investigated in the literature, both in the context of environments with
perfect and imperfect information about the system (in the last case, the
environment has only a partial view of the system's control states and stack
content). For standard CTL, PMC with imperfect information is known to be
undecidable. If the stack content is assumed to be visible, then the problem is
decidable and 2EXPTIME-complete (matching the complexity of PMC with perfect
information against CTL). The decidability status of PMC with imperfect
information against CTL restricted to the case where the depth of the stack
content is visible is open. In this paper, we show that with this restriction,
PMC with imperfect information against CTL remains undecidable. On the other
hand, we individuate an interesting subclass of OPDS with visible stack content
depth such that PMC with imperfect information against the existential fragment
of CTL is decidable and in 2EXPTIME. Moreover, we show that the program
complexity of PMC with imperfect information and visible stack content against
CTL is 2EXPTIME-complete (hence, exponentially harder than the program
complexity of PMC with perfect information, which is known to be
EXPTIME-complete).Comment: In Proceedings GandALF 2011, arXiv:1106.081
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