291 research outputs found
Seeking for a fingerprint: analysis of point processes in actigraphy recording
Motor activity of humans displays complex temporal fluctuations which can be
characterized by scale-invariant statistics, thus documenting that structure
and fluctuations of such kinetics remain similar over a broad range of time
scales. Former studies on humans regularly deprived of sleep or suffering from
sleep disorders predicted change in the invariant scale parameters with respect
to those representative for healthy subjects. In this study we investigate the
signal patterns from actigraphy recordings by means of characteristic measures
of fractional point processes. We analyse spontaneous locomotor activity of
healthy individuals recorded during a week of regular sleep and a week of
chronic partial sleep deprivation. Behavioural symptoms of lack of sleep can be
evaluated by analysing statistics of duration times during active and resting
states, and alteration of behavioural organization can be assessed by analysis
of power laws detected in the event count distribution, distribution of waiting
times between consecutive movements and detrended fluctuation analysis of
recorded time series. We claim that among different measures characterizing
complexity of the actigraphy recordings and their variations implied by chronic
sleep distress, the exponents characterizing slopes of survival functions in
resting states are the most effective biomarkers distinguishing between healthy
and sleep-deprived groups.Comment: Communicated at UPON2015, 14-17 July 2015, Barcelona. 21 pages, 11
figures; updated: figures 4-7, text revised, expanded Sec. 1,3,
Is flood defense changing in nature? Shifts in the flood defense strategy in six European countries
In many countries, flood defense has historically formed the core of flood risk management but this strategy is now evolving with the changing approach to risk management. This paper focuses on the neglected analysis of institutional changes within the flood defense strategies formulated and implemented in six European countries (Belgium, England, France, the Netherlands, Poland, and Sweden). The evolutions within the defense strategy over the last 30 years have been analyzed with the help of three mainstream institutional theories: a policy dynamics-oriented framework, a structure-oriented institutional theory on path dependency, and a policy actors-oriented analysis called the advocacy coalitions framework. We characterize the stability and evolution of the trends that affect the defense strategy in the six countries through four dimensions of a policy arrangement approach: actors, rules, resources, and discourses. We ask whether the strategy itself is changing radically, i.e., toward a discontinuous situation, and whether the processes of change are more incremental or radical. Our findings indicate that in the European countries studied, the position of defense strategy is continuous, as the classical role of flood defense remains dominant. With changing approaches to risk, integrated risk management, climate change, urban growth, participation in governance, and socioeconomic challenges, the flood defense strategy is increasingly under pressure to change. However, these changes can be defined as part of an adaptation of the defense strategy rather than as a real change in the nature of flood risk management
Hyperon Polarization in the Constituent Quark Model
We consider mechanism for hyperon polarization in inclusive production. The
main role belongs to the orbital angular momentum and polarization of the
strange quark-antiquark pairs in the internal structure of the constituent
quarks. We consider a nucleon as a core consisting of the constituent quarks
embedded into quark condensate. The nonperturbative hadron structure is based
on the results of chiral quark models.Comment: 14 pages, LaTeX, 2 Figures, References adde
Enhanced light intensity increases flavonol and anthocyanin concentrations but reduces flavone levels in the cotyledons of common buckwheat seedlings
The effects of two light intensities on the concentration of several flavonoids were investigated in the cotyledons of common buckwheat seedlings. The study was performed on four days old seedlings of cvs. Hruszowska, Panda, Kora and Red Corolla. One group of seedlings was grown under exposure to 180 ± 20 μmol · m−2 · s−1 photosynthetically active radiation, whereas the other group was exposed to 360 ± 20 μmol · m−2 · s−1. The experiment lasted 5 days. The results revealed that light intensity induces changes in the levels of flavonols and flavones. Increased light intensity contributed to a decrease in the concentrations of all flavone C-glucosides: orientin (luteolin-8-C-glucoside) and iso-orientin (luteolin-6-C-glucoside), and apigenin: vitexin (apigenin-8-C-glucoside) and iso-vitexin (apigenin-6-C-glucoside). Simultaneously, a substantial increase in the content of flavonols, i.e. quercetin O-glycosides, was found. To the best of our knowledge, this is the first evidence to demonstrate the contrary responses of plant flavonols and flavones to light intensity. The content of anthocyanin also increased under exposure to higher light intensity. Our results indicate that quercetin O-glycosides can play a similar role to anthocyanins in the cotyledons of common buckwheat seedlings. Results of correlation analysis indicate that the increase in flavonol and anthocyanin concentrations in response to higher light intensity is maintained through reduced accumulation of flavones and proanthocyanidins
Effect of the 5-HTTLPR polymorphism on affective temperament, depression and body mass index in obesity
Background and aim: Many studies show high prevalence of affective disorders in obese patients.
Affective temperament is a subclinical manifestation of such conditions. The 5-HTT gene encoding the
serotonin transporter may be involved in both mood and eating dysregulation. The aim of this study was
to investigate the influence of a polymorphism in the 5-HTT gene on affective temperament types,
depressive symptoms and Body Mass Index (BMI) in obese patients.
Methods: This study involved 390 patients (237 females, and 153 males) with obesity. The TEMPS-A
questionnaire, Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HDRS) were used
to evaluate affective temperaments and prevalence of depression. DNA was obtained for serotonin
transporter gene-linked polymorphism (5-HTTLPR) genotyping.
Results: In obese patients S/S genotype was associated with depressive and L/L with cyclothymic temperament.
Subjects with L/L genotype presented significantly higher BMI and greater intensity of
depressive symptoms in BDI and HDRS. Females scored higher in anxious and depressive, while males in
hyperthymic, cyclothymic and irritable temperaments. Females scored higher in BDI (subjective
depression) while males in HDRS (objective depression).
Limitations: TEMPS-A, BDI and HDRS are frequently used in studies on affective disorders. However,
these methods do not examine all dimensions of mood and personality.
Conclusions: In obese patients S allele of 5-HTTLPR was associated with development of depressive
temperament while L allele corresponded with greater obesity and prevalence of depression. Different
mechanisms may be involved in manifestation of depression in males and females with obesity
Higgs Boson Production and Weak Boson Structure
The influence of the QCD structure of the weak bosons on the Higgs boson
production in - scattering is studied. The energy and Higgs boson mass
dependence of the cross-section, following from the new contributions, is
calculated.Comment: 8 pages, 3 figures, compressed uuencoded Postscript fil
Nano-Aptamer for Breast Cancer Imaging: Initial Considerations.
The application of aptamers especially in the use of drug delivery systems (DDSs) has the potential to develop in vivo nanoparticles for theranosis (therapy+diagnosis). With the advent of medical imaging and radiotherapeutics, this area of research developing the next era of radiopharmaceuticals is both attractive and promising. Overall, nano-radiopharmaceuticals have the potential to solve several problems regarding the in vivo stability of aptamers. This paper discusses a study in the development and proof-of-concept of nano-aptamers and supporting its use as a nano-radiopharmaceutical for the treatment of breast cancer and other potentially related disease states
Information transmission in oscillatory neural activity
Periodic neural activity not locked to the stimulus or to motor responses is
usually ignored. Here, we present new tools for modeling and quantifying the
information transmission based on periodic neural activity that occurs with
quasi-random phase relative to the stimulus. We propose a model to reproduce
characteristic features of oscillatory spike trains, such as histograms of
inter-spike intervals and phase locking of spikes to an oscillatory influence.
The proposed model is based on an inhomogeneous Gamma process governed by a
density function that is a product of the usual stimulus-dependent rate and a
quasi-periodic function. Further, we present an analysis method generalizing
the direct method (Rieke et al, 1999; Brenner et al, 2000) to assess the
information content in such data. We demonstrate these tools on recordings from
relay cells in the lateral geniculate nucleus of the cat.Comment: 18 pages, 8 figures, to appear in Biological Cybernetic
Transverse polarization in inclusive quasi-real photoproduction: quark scattering model
The transverse polarization of hyperons produced in the inclusive
reaction at the 27.6 GeV beam energy is assumed to appear mostly via
scattering of the strange quark in a color field. Results of application of
such an idea to the preliminary data of HERMES are presented. Contributions of
, , and resonances to the polarization are taken into
account.Comment: 5 pages, 5 figures, corrected according to version accepted by
Physics of Atomic Nucle
Exploring a Controls-Based Assessment of Infrastructure Vulnerability
Assessing the vulnerability of an enterprise's infrastructure is an important step in judging the security of its network and the trustworthiness and quality of the information that flows through it. Currently, low-level infrastructure vulnerability is often judged in an ad hoc manner, based on the criteria and experience of the assessors. While methodological approaches to assessing an organisation's vulnerability exist, they are often targeted at higher-level threats, and can fail to accurately represent risk. Our aim in this paper therefore, is to explore a novel, structured approach to assessing low-level infrastructure vulnerability. We do this by placing the emphasis on a controls-based evaluation over a vulnerability-based evaluation. This work aims to investigate a framework for the pragmatic approach that organisations currently use for assessing low-level vulnerability. Instead of attempting to find vulnerabilities in infrastructure, we instead assume the network is insecure, and measure its vulnerability based on the controls that have (and have not) been put in place. We consider different control schemes for addressing vulnerability, and show how one of them, namely the Council on Cyber Security's Top 20 Critical Security Controls, can be applied
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