778 research outputs found
Combining CV and RP data: a note on the relationship between consistency and rationality
In this paper, we show that, when combining revealed (RP) and stated (SP) data, for marginal changes in quality of environmental goods, rationality implies consistency, as the consistency conditions coincide with a subset of the conditions for rationality.combined (RP and SP) individual data; rationality; data consistency
SHStream: Self-Healing Framework for HTTP Video-Streaming
HTTP video-streaming is leading delivery of video
content over the Internet. This phenomenon is explained by the
ubiquity of web browsers, the permeability of HTTP traffic
and the recent video technologies around HTML5. However,
the inclusion of multimedia requests imposes new requirements
on web servers due to responses with lifespans that can reach
dozens of minutes and timing requirements for data fragments
transmitted during the response period. Consequently, web-
servers require real-time performance control to avoid playback
outages caused by overloading and performance anomalies. We
present
SHStream
, a self-healing framework for web servers
delivering video-streaming content that provides (1) load admit-
tance to avoid server overloading; (2) prediction of performance
anomalies using online data stream learning algorithms; (3)
continuous evaluation and selection of the best algorithm for
prediction; and (4) proactive recovery by migrating the server
to other hosts using container-based virtualization techniques.
Evaluation of our framework using several variants of
Hoeffding
trees
and
ensemble algorithms
showed that with a small number of
learning instances, it is possible to achieve approximately 98% of
recall
and 99% of
precision
for failure predictions. Additionally,
proactive failover can be performed in less than 1 secon
Combining Averting Behavior and Contingent Valuation Data: An Application to Drinking Water Treatment
This paper is an empirical application that combines averting behavior with contingent valuation data. Consistency tests are performed incorporating alternative heteroscedastic structures in the bivariate probit models by taking advantage of the different information content that characterizes each data source. We look at three covariates not yet examined in the literature when combining stated and revealed preferred data to explain the variance in the models: income, the bid in the contingent valuation questionnaire, and the distance between the bid and the averting expenditures with drinking water. The models estimated include between and within data sources heteroscedasticity. The results obtained allow the combination of the two data sources under a common preference structure.averting behavior, combination of data sets, consistency tests, contingent valuation, revealed preferred data
Reboot-based Recovery of Performance Anomalies in Adaptive Bitrate Video-Streaming Services
Performance anomalies represent one common type
of failures in Internet servers. Overcoming these failures without
introducing server downtimes is of the utmost importance in
video-streaming services. These services have large user abandon-
ment costs when failures occur after users watch a significant part
of a video. Reboot is the most popular and effective technique for
overcoming performance anomalies but it takes several minutes
from start until the server is warmed-up again to run at its
full capacity. During that period, the server is unavailable or
provides limited capacity to process end-users’ requests. This
paper presents a recovery technique for performance anomalies
in HTTP Streaming services, which relies on Container-based
Virtualization to implement an efficient multi-phase server reboot
technique that minimizes the service downtime. The recovery
process includes analysis of variance of request-response times
to delimit the server warm-up period, after which the server
is running at its full capacity. Experimental results show that
the Virtual Container recovery process completes in
72
seconds,
which contrasts with the
434
seconds required for full operating
system recovery. Both recovery types generate service downtimes
imperceptible to end-users
Plant protein blends in diets for Senegalese sole affect skeletal muscle growth, flesh texture and the expression of related genes
Author's accepted version (postprint).Available from 26/11/2017.Skeletal muscle growth and flesh quality of Senegalese sole fed diets containing increasing levels of plant protein blends to replace fishmeal were evaluated using muscle cellularity, texture profile and gene expression. A control fish meal-based diet (FM) was compared with three isonitrogenous (54%) and isolipidic (9%) diets with increasing levels of plant protein (PP) blends (50% PP50, 75% PP75 and 100% PP100). By the end of the experiment sole fed PP50 and PP75 had a final body length similar to the CTR (25 cm), but fish fed PP100 were significantly smaller (23 cm). Total FM replacement by PP sources resulted in significantly smaller muscle cross sectional area (CSA) mainly due to a decrease in the muscle fibre size as the total number of fibres did not vary significantly among treatments. The dietary incorporation of PP significantly reduced the expression of several key genes involved in myogenesis and muscle growth (mrf4, fgf6, myhc and mylc2). Fillet texture analysed instrumentally was affected by the total substitution of FM. Fish fed PP100 diet had a significantly higher modulus of elasticity, i.e. lower flesh stiffness, compared with the other groups. Muscle fibre size was moderately related (r = − 0.573) to the modulus of elasticity and positively correlated with the expression of lysyl oxidase (r = 0.495). The observed changes in muscle cellularity could not be associated with the expression of texture-related genes (capn2, ctsb, ctsd), since no significant differences were observed among diets. The present results point towards a modulation of the expression of several muscle growth related genes by increasing levels of PP sources that alter muscle cellularity and textural properties of Senegalese sole when total FM is replaced by PP
Cyclobenzaprine raises ROS levels in Leishmania infantum and reduces parasite burden in Infected mice
11 p.-5 fig. Ferreira Cunha-Júnior, Edézio et al.Background
The leishmanicidal action of tricyclic antidepressants has been studied and evidences have pointed that their action is linked to inhibition of trypanothione reductase, a key enzyme in the redox metabolism of pathogenic trypanosomes. Cyclobenzaprine (CBP) is a tricyclic structurally related to the antidepressant amitriptyline, differing only by the presence of a double bond in the central ring. This paper describes the effect of CBP in experimental visceral leishmaniasis, its inhibitory effect in trypanothione reductase and the potential immunomodulatory activity.Methodology/Principal Findings
In vitro antileishmanial activity was determined in promastigotes and in L. infantum-infected macrophages. For in vivo studies, L. infantum-infected BALB/c mice were treated with CBP by oral gavage for five days and the parasite load was estimated. Trypanothione reductase activity was assessed in the soluble fraction of promastigotes of L. infantum. For evaluation of cytokines, L. infantum-infected macrophages were co-cultured with BALB/c splenocytes and treated with CBP for 48 h. The supernatant was analyzed for IL-6, IL-10, MCP-1, IFN-γ and TNF-α. CBP demonstrated an IC50 of 14.5±1.1μM and an IC90 of 74.5±1.2 μM in promastigotes and an IC50 of 12.6±1.05 μM and an IC90 of 28.7±1.3 μM in intracellular amastigotes. CBP also reduced the parasite load in L. infantum-infected mice by 40.4±10.3% and 66.7±10.5% in spleen at 24.64 and 49.28 mg/kg, respectively and by 85.6±5.0 and 89.3±4.8% in liver at 24.64 and 49.28mg/kg, after a short-term treatment. CBP inhibited the trypanothione reductase activity with a Ki of 86 ± 7.7 μM and increased the ROS production in promastigotes. CBP inhibited in 53% the production of IL-6 in infected macrophages coculture.Conclusion/Significance
To the best of our knowledge, this study is the first report of the in vivo antileishmanial activity of the FDA-approved drug CBP. Modulation of immune response and induction of oxidative stress in parasite seem to contribute to this efficacy.This work was supported by Programa Estratégico de Apoio à Pesquisa em Saúde,FIOCRUZ/Conselho Nacional de Desenvolvimento Científico e Tecnológico - www.cnpq.br, (PAPES/
CNPq 407680/2012-8 to ECTS and 407590/2012-9
to EEAA), Fundação de Apoio a Pesquisa do Estado do Rio de Janeiro ± www.faperj.br (Fellow and grant E-26/010.001828/2016 to EFCJ), Conselho Nacional de Desenvolvimento CientõÂfico e
TecnoloÂgico (CNPq/Universal grant 470627/2013-1 to EEAA), São Paulo Research Foundation - www.fapesp.br (FAPESP 2015/23403-9 to AGT),Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad
FEDER - www.idi.mineco.gob.es/ (SAF2015-65740-R) and Subdirección General de Redes y Centros de Investigación Cooperativa-FEDER -www.isciii.es/ (RD12/0018/0007) (to LR).Peer reviewe
Monitoring programmes: the fundamental component of estuaries management: how to design one?
This article focuses on the design of a conceptual framework to design and
assess environmental estuarine monitoring programmes, including the networks,
to detect quality status changes in coastal areas within environmental
management programmes. Monitoring is a fundamental component in any
management system, and in particular in sensitive areas under strong human
pressures, like estuaries. These pressures will be reflected in impacts in the
ecosystem and also in responses from it. A monitoring program including the
network and the indicators measured, should be designed to be able to identify
the i) pressures, ii) the state and effects, and iii) the responses of human action in
the estuary according to casualty chains, also the monitoring performance should be measured to assess the effectiveness of the monitoring program itself.
Answers to these needs are studied in this article, namely in what concerns the
selection and location of the monitoring stations. To evaluate the “best”
monitoring design one should first clearly identify the objectives of the network
and which indicators (in the sense of important variables that reflect
environmental attributes) are most appropriate for the particular situation. In this
work two methods for monitoring network design will be evaluated, namely i)
variance-reduction based, and ii) space-filling. These two are examples of a
statistically-based method, and of a random-allocation-based method. The most
appropriate objective functions are used to reflect the objectives of the
monitoring. In all cases the objective function models are solved with the
simulated annealing meta-heuristic algorithm, implemented by the team to solve
monitoring optimisation problems. Due to the amount and quality of the
information available, the Sado estuary is used as a case-study to demonstrate the
results of the methods and helping in the comparative analysis.info:eu-repo/semantics/publishedVersio
The effects of different concentrations of the α2-Adrenoceptor Agonist Medetomidine on basal excitatory synaptic transmission and synaptic plasticity in hippocampal slices of adult mice
α2-Adrenoceptor agonists are used frequently in human and veterinary anesthesia as sedative/analgesic drugs. However, they can impair cognition. Little is known about the concentration-dependent effects of α2-adrenoceptor agonists on synaptic plasticity, the neurophysiological basis of learning and memory. Therefore, we investigated the effects of different concentrations of medetomidine, an α2-adrenoceptor agonist, on basal excitatory synaptic transmission and on 2 forms of synaptic plasticity: paired-pulse facilitation (PPF) and long-term potentiation (LTP).Funding: This work was supported by FCT (Lisbon, Portugal) and cofunded by COMPETE: 01-0124-FEDER-009497 (Lisbon, Portugal), through the project grants PTDC/CVT/099022/2008 and PTDC/SAU-NSC/122254/2010 and through a personal PhD grant (SFRH /BD/48883/2008) to Patrícia do Céu Oliveira Ribeiro and by QREN (09-68-ESR-FP-010).info:eu-repo/semantics/publishedVersio
Role of Visual Assessment of High-Quality Cakes in Emotional Response of Consumers
[EN] Thinking of the present gastronomic trends is inevitable when talking about innovation in haute pastry. Launching a successful product that meets consumers' high expectations despite the rising demand for new creations is increasingly complex. For this reason, sensory analysis studies are more and more interested in studying the emotional response evoked by these products to better understand and improve user experiences. The main goal of this work was to conduct a study to analyze the emotional arousal of consumers after the visualization of five haute patisserie cakes. An online questionnaire with the EsSense Profile (R) scale and CATA methodology were used for data collection. The EsSense Profile (R) is a predefined and validated scale that measures food-related emotions, which includes 39 terms. When analyzing the emotions expressed by all the participants, 22 were statistically significant, of which 14 were classified as positive, 6 as neutral, and only 2 were negative. By analyzing the responses by gender, we observed differences in the number of elicited emotional terms: females showed significant differences between cakes for 18 emotion terms compared to 8 terms for males. The results obtained support the importance of the emotional profile to understand consumers' expectations and behavior.Author Cunha acknowledges financial support from National Funds from FCT-Fundacao para a Ciencia e a Tecnologia within the scope of UIDB/05748/2020 and UIDP/05748/2020.Alba-Martínez, J.; Bononad-Olmo, A.; Igual Ramo, M.; Cunha, LM.; Martínez-Monzó, J.; García-Segovia, P. (2022). Role of Visual Assessment of High-Quality Cakes in Emotional Response of Consumers. Foods. 11(10):1-15. https://doi.org/10.3390/foods11101412115111
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