287 research outputs found
Higgsino dark matter in partly supersymmetric models
Models where supersymmetry (SUSY) is manifest only in a sector of the
low-energy spectrum have been recently proposed as an alternative to the MSSM.
In these models the electroweak scale is explained by a fine-tuning between
different Higgs mass contributions (split-SUSY models), or by the localization
of the Higgs sector in a point of an extra dimension where all the mass
parameters are suppressed by the metric (partly-SUSY models). Therefore, the
presence of a good dark matter candidate becomes the main motivation for
(partial) low-energy SUSY. We study this issue in minimal frameworks where the
higgsinos are the only light supersymmetric particles. Whereas in split-SUSY
models the higgsino should have a mass around 1 TeV, we show that in
partly-SUSY models the lightest higgsino could also be found below MW.Comment: 12 pages, 3 figures, version to appear in Phys. Rev.
Piloting a holistic information culture program: The experience of CETYS Universidad system of libraries
This article presents the staff, structure, methods and preliminary results from the pilot of a holistic information literacy program developed in the System of Libraries of CETYS Universidad in Mexico. âInformation Culture Developmentâ (ICD) is driven by action research (AR) and the concept of information culture (IC), comprised of information literacy (IL), digital literacy (DL), and research competences. ICD aims at developing these competences and supporting reflection and improvement upon university practices related to curriculum, teaching, and research. ICDâs initiatives and products were divided into four axes: a) curriculum and learning support, b) information and digital literacies development, c) research and scientific communication support, and d) evaluation and communication of results. ICDâs pilot involved workshops and activities framed within an AR perspective and a mixed methods approach. Preliminary results determine the success of activities with academics and students regarding their strengths and weaknesses in IC-related competencies
On the criticality of inferred models
Advanced inference techniques allow one to reconstruct the pattern of
interaction from high dimensional data sets. We focus here on the statistical
properties of inferred models and argue that inference procedures are likely to
yield models which are close to a phase transition. On one side, we show that
the reparameterization invariant metrics in the space of probability
distributions of these models (the Fisher Information) is directly related to
the model's susceptibility. As a result, distinguishable models tend to
accumulate close to critical points, where the susceptibility diverges in
infinite systems. On the other, this region is the one where the estimate of
inferred parameters is most stable. In order to illustrate these points, we
discuss inference of interacting point processes with application to financial
data and show that sensible choices of observation time-scales naturally yield
models which are close to criticality.Comment: 6 pages, 2 figures, version to appear in JSTA
Association between exposure to particulate matter during pregnancy and multidimensional development in schoolâage children: A crossâsectional study in Italy
Air pollutants can potentially affect the development of children. However, data on the effect of exposure to air pollution during pregnancy and developmental outcomes in school children are rare. We investigated the link between prenatal exposure to particulate matters smaller than 10 microns (PM10) and the development of school-age children in multiple domains. Cross-sectional data were collected in Italy between 2013 and 2014. Children aged between 5 and 8 years (n = 1187) were assessed on cognitive, communication, socio-emotional, adaptive, and motor developmental domains using the Developmental Profile 3 questionnaire. The monthly average concentration of PM10 during the entire fetal period was linked to the municipality of residence of the children. The increase in the prenatal PM10 was associated with a decrease in the cognitive score during the second (+13.2 ”g/m3 PM10 increase: â0.30 points; 95%CI: â0.12ââ0.48) and third trimesters of pregnancy (â0.31 points; 95%CI: â0.11ââ0.50). The communicative domain was also negatively influenced by PM10 increases in the second trimester. The development of cognitive and communicative abilities of children was negatively associated with the exposure to PM10 during the period of fetal development, confirming that exposure to air pollution during pregnancy can potentially hinder the development of the brain
Combined effect of active coating and modified atmosphere packaging on prolonging the shelf life of low-moisture Mozzarella cheese
Abstract In this work, the effect of active coating on the shelf life of low-moisture Mozzarella cheese packaged in air and modified atmosphere (MAP) was studied. The active coating was based on sodium alginate (2%, wt/vol) and potassium sorbate (1%, wt/vol). The MAP was made up of 75% CO 2 and 25% N 2 (MAP1), 25% CO 2 and 75% N 2 (MAP2), or 50% CO 2 and 50% N 2 (MAP3). The product quality decay was assessed by monitoring microbiological and sensory changes during storage at 4, 8, and 14°C. Results showed that the combination of active coating and MAP was able to improve the preservation of low-moisture Mozzarella cheese. Specifically, the shelf life increased up to 160 d for samples stored at 4°C, and 40 and 11 d for those at 8 and 14°C, respectively. A faster quality decay for untreated samples packaged in air was observed. In particular, the Pseudomonas spp. growth and the appearance of molds were responsible for product unacceptability. The combination of active coating and MAP represents a strategic solution to prolong the shelf life of low-moisture Mozzarella cheese and to ensure the safety of the product under thermal abuse conditions
HCV clearance patterns in saliva and serum of patients with chronic HCV infection under interferon plus ribavirin therapy
This is the peer reviewed version of the article which has been published in final form at Wiley Online Library. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for self-archiving[Abstract] Statements of the problem:â Hepatitis C virus (HCV)-RNA is often present in saliva of HCV-infected patients, with plasma viral load being the only known predictable factor. Interferon plus ribavirin therapy yields a sustained reduction in HCV viremia. This study aimed to assess the presence of HCV in saliva and serum specimens from patients undergoing this combination therapy (CT).
Method of study:â Paired serum and saliva specimens were collected from 44 chronic HCV-infected patients at basal time, 4 and 12 weeks after CT onset, at the end of treatment and 6 months latter. Serum HCV-RNA levels were determined by the polymerase chain reaction (PCR) Amplicor system. Presence of HCV-RNA in saliva was tested by a highly sensitive non-commercialized nested-PCR.
Results:â The HCV-RNA was detected in 26 saliva specimens at basal time (59.1%). In 34.1% of cases, a concordance viral clearance pattern in serum and saliva was observed in both responders (pattern 1a) and non-responders (pattern 1b). In pattern 2 (13.6% of cases), HCV was detected longer during CT in serum than in saliva (pattern 2a) or in saliva than in serum (pattern 2b). In 11.3% of patients, viral clearance was corroborated either in their serum (pattern 3a) or in their saliva (pattern 3b), but not in both fluids. Of the eight primary responders with 1a clearance pattern, seven were sustained responders. None of the patients with 2a clearance pattern was a sustained responder. Of the two primary responders showing the 3b salivary pattern, one had already relapsed in the first 6 months of follow up.
Conclusions:â The present results suggest that the monitoring of salivary levels of HCV would be a helpful means of determining sustained antiviral effects of interferon and ribavirin in the treatment of HCV disease
Financial correlations at ultra-high frequency: theoretical models and empirical estimation
A detailed analysis of correlation between stock returns at high frequency is
compared with simple models of random walks. We focus in particular on the
dependence of correlations on time scales - the so-called Epps effect. This
provides a characterization of stochastic models of stock price returns which
is appropriate at very high frequency.Comment: 22 pages, 8 figures, 1 table, version to appear in EPJ
Beyond inverse Ising model: structure of the analytical solution for a class of inverse problems
I consider the problem of deriving couplings of a statistical model from
measured correlations, a task which generalizes the well-known inverse Ising
problem. After reminding that such problem can be mapped on the one of
expressing the entropy of a system as a function of its corresponding
observables, I show the conditions under which this can be done without
resorting to iterative algorithms. I find that inverse problems are local (the
inverse Fisher information is sparse) whenever the corresponding models have a
factorized form, and the entropy can be split in a sum of small cluster
contributions. I illustrate these ideas through two examples (the Ising model
on a tree and the one-dimensional periodic chain with arbitrary order
interaction) and support the results with numerical simulations. The extension
of these methods to more general scenarios is finally discussed.Comment: 15 pages, 6 figure
Manufacture and characterization of gluten-free spaghetti enriched with vegetable flour
The manufacture and characterization of gluten-free spaghetti based on maize flour and different vegetable
flours (artichoke, asparagus, pumpkin, zucchini, tomato, yellow pepper, red pepper, green pepper,
carrot, broccoli, spinach, eggplant and fennel) were addressed in this study. The screening of the vegetable
flours showed that homogeneity, color, fibrous, taste and odor were the parameters that have
most influenced the overall quality of the dry spaghetti. The spaghetti added with yellow pepper flour
was chosen for further analysis because of its highest sensory quality; in contrast, it recorded low carotenoids
content due to the high temperature of the drying process (cycle named as HTDC). Therefore,
an optimization of the drying cycle was performed (lower temperature) on the yellow pepper flour (cycle
named as LTDC) that resulted in an increase of the carotenoids content. Although the spaghetti with low
temperature yellow pepper flour had a higher cooking loss and lower instrumental hardness when
compared to the spaghetti made with only maize flour (CTRL) it however had a significantly higher
protein and dietary fiber content. Moreover there was no significant difference in the amount of glucose
released during in vitro digestion for this spaghetti sample with respect to the CTRL sample
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