Time-varying correlation coefficients estimation and its application to dynamic connectivity analysis of fMRI

Exploration of the dynamics of functional brain connectivity based on the correlation coefficients of functional magnetic resonance imaging (fMRI) data is important for understanding the brain mechanisms. Because fMRI data are time-varying in nature, the functional connectivity shows substantial fluctuations and dynamic characteristics. However, an effective method for estimating time-varying functional connectivity is lacking, which is mainly due to the difficulty in choosing an appropriate window to localize the time-varying correlation coefficients (TVCC). This paper introduces a novel method for adaptively estimating the TVCC of non-stationary signals and studies its application to infer dynamic functional connectivity of fMRI data in a visual task. The proposed method employs a sliding window having a certain bandwidth to estimate the TVCC locally and the window bandwidths are selected adaptively by a local plug-in rule to minimize the mean squared error. The results show that the functional connectivity changes in the visual task are transient, which suggests that simply assuming sustained connectivity changes during task period might not be sufficient to capture dynamic connectivity changes induced by tasks.published_or_final_versio

Lightest sterile neutrino abundance within the nuMSM

We determine the abundance of the lightest (dark matter) sterile neutrinos created in the Early Universe due to active-sterile neutrino transitions from the thermal plasma. Our starting point is the field-theoretic formula for the sterile neutrino production rate, derived in our previous work [JHEP 06(2006)053], which allows to systematically incorporate all relevant effects, and also to analyse various hadronic uncertainties. Our numerical results differ moderately from previous computations in the literature, and lead to an absolute upper bound on the mixing angles of the dark matter sterile neutrino. Comparing this bound with existing astrophysical X-ray constraints, we find that the Dodelson-Widrow scenario, which proposes sterile neutrinos generated by active-sterile neutrino transitions to be the sole source of dark matter, is only possible for sterile neutrino masses lighter than 3.5 keV (6 keV if all hadronic uncertainties are pushed in one direction and the most stringent X-ray bounds are relaxed by a factor of two). This upper bound may conflict with a lower bound from structure formation, but a definitive conclusion necessitates numerical simulations with the non-equilibrium momentum distribution function that we derive. If other production mechanisms are also operative, no upper bound on the sterile neutrino mass can be established.Comment: 34 pages. v2: clarifications and a reference added; published version. v3: erratum appende

Intrapreneurial self-capital training: a case study of an Italian university student

This chapter presents a case study which describes the application of the Intrapreneurial Self-Capital Training with a final-year postgraduate female biology student, Erica. The chapter presents an overview of theory that is relevant to the world of work and the conceptual dimensions of intrapreneurial self capital (ISC). Training for ISC aims to assist young people to identify their personal strengths in terms of intrapreneurship and career adaptability. A qualitative instrument, the Life Adaptability Qualitative Assessment (LAQuA) was administered before and after the training to detect meaningful changes in the participant’s narratives about career adaptability and enhanced reflexivity. The LAQuA coding system revealed enhancements to the participant’s awareness about her personal intrapreneurial resources and career adaptability. The relevance of ISC to employability and career services in education contexts is discussed along with recommendations for research into ISC training

A harmonized atlas of mouse spinal cord cell types and their spatial organization

Single-cell RNA sequencing data can unveil the molecular diversity of cell types. Cell type atlases of the mouse spinal cord have been published in recent years but have not been integrated together. Here, we generate an atlas of spinal cell types based on single-cell transcriptomic data, unifying the available datasets into a common reference framework. We report a hierarchical structure of postnatal cell type relationships, with location providing the highest level of organization, then neurotransmitter status, family, and finally, dozens of refined populations. We validate a combinatorial marker code for each neuronal cell type and map their spatial distributions in the adult spinal cord. We also show complex lineage relationships among postnatal cell types. Additionally, we develop an open-source cell type classifier, SeqSeek, to facilitate the standardization of cell type identification. This work provides an integrated view of spinal cell types, their gene expression signatures, and their molecular organization

Fibrin Sealants and Axillary Lymphatic Morbidity. A Systematic Review and Meta-Analysis of 23 Clinical Randomized Trials

Background: use of fibrin sealants following pelvic, paraaortic, and inguinal lymphadenec- tomy may reduce lymphatic morbidity. The aim of this meta-analysis is to evaluate if this finding applies to the axillary lymphadenectomy. Methods: randomized trials evaluating the efficacy of fibrin sealants in reducing axillary lymphatic complications were included. Lymphocele, drainage output, surgical-site complications, and hospital stay were considered as outcomes. Results: twenty-three randomized studies, including patients undergoing axillary lymphadenectomy for breast cancer, melanoma, and Hodgkin’s disease, were included. Fibrin sealants did not affect axillary lymphocele incidence nor the surgical site complications. Drainage output, days with drainage, and hospital stay were reduced when fibrin sealants were applied (p < 0.0001, p < 0.005, p = 0.008). Conclusion: fibrin sealants after axillary dissection reduce the total axillary drainage output, the duration of drainage, and the hospital stay. No effects on the incidence of postoperative lymphocele and surgical site complications rate are found

A semi-parametric approach to estimate risk functions associated with multi-dimensional exposure profiles: application to smoking and lung cancer

A common characteristic of environmental epidemiology is the multi-dimensional aspect of exposure patterns, frequently reduced to a cumulative exposure for simplicity of analysis. By adopting a flexible Bayesian clustering approach, we explore the risk function linking exposure history to disease. This approach is applied here to study the relationship between different smoking characteristics and lung cancer in the framework of a population based case control study

The Arabidopsis thaliana knockout mutant for phytochelatin synthase1 (cad1-3) Is defective in callose deposition, bacterial pathogen defense and auxin content, but shows an increased stem lignification

The enzyme phytochelatin synthase (PCS) has long been studied with regard to its role in metal(loid) detoxification in several organisms, i.e., plants, yeasts, and nematodes. It is in fact widely recognized that PCS detoxifies a number of heavy metals by catalyzing the formation of thiol-rich oligomers, namely phytochelatins, from glutathione and related peptides. However, recent investigations have highlighted other possible roles played by the PCS enzyme in the plant cell, e.g., the control of pathogen-triggered callose deposition. In order to examine novel aspects of Arabidopsis thaliana PCS1 (AtPCS1) functions and to elucidate its possible roles in the secondary metabolism, metabolomic data of A. thaliana wild-type and cad1-3 mutant were compared, the latter lacking AtPCS1. HPLC-ESI-MS analysis showed differences in the relative levels of metabolites from the glucosinolate and phenylpropanoid pathways between cad1-3 and wild-type plants. Specifically, in control (Cd-untreated) plants, higher levels of 4-methoxy-indol 3-ylmethylglucosinolate were found in cad1-3 plants vs. wild-type. Moreover, the cad1-3 mutant showed to be impaired in the deposit of callose after Cd exposure, suggesting that AtPCS1 protects the plant against the toxicity of heavy metals not only by synthesizing PCs, but also by contributing to callose deposition. In line with the contribution of callose in counteracting Cd toxicity, we found that another callose-defective mutant, pen2-1, was more sensitive to high concentrations of Cd than wild-type plants. Moreover, cad1-3 plants were more susceptible than wild-type to the hemibiotrophic bacterial pathogen Pseudomonas syringae. The metabolome also revealed differences in the relative levels of hydroxycinnamic acids and flavonols,with consequences on cell wall properties and auxin content, respectively. First, increased lignification in the cad1-3 stems was found, probably aimed at counteracting the entry of Cd into the inner tissues. Second, in cad1-3 shoots, increased relative levels of kaempferol 3,7 dirhamnoside and quercetin hexoside rhamnoside were detected. These flavonols are endogenous inhibitors of auxin transport in planta; auxin levels in both roots and shoots of the cad1-3 mutant were in fact lower than those of the wild-type. Overall, our data highlight novel aspects of AtPCS1 functions in A. thaliana

B-L Cosmic Strings in Heterotic Standard Models

E_{8} X E_{8} heterotic string and M-theory, when compactified on smooth Calabi-Yau manifolds with SU(4) vector bundles, can give rise to softly broken N=1 supersymmetric theories with the exact matter spectrum of the MSSM, including three right-handed neutrinos and one Higgs-Higgs conjugate pair of supermultiplets. These vacua have the SU(3)_{C} X SU(2)_{L} X U(1)_{Y} gauge group of the standard model augmented by an additional gauged U(1)_{B-L}. Their minimal content requires that the B-L symmetry be spontaneously broken by a vacuum expectation value of at least one right-handed sneutrino. The soft supersymmetry breaking operators can induce radiative breaking of the B-L gauge symmetry with an acceptable B-L/electroweak hierarchy. In this paper, it is shown that U(1)_{B-L} cosmic strings occur in this context, potentially with both bosonic and fermionic superconductivity. We present a numerical analysis that demonstrates that boson condensates can, in principle, form for theories of this type. However, the weak Yukawa and gauge couplings of the right-handed sneutrino suggests that bosonic superconductivity will not occur in the simplest vacua in this context. The electroweak phase transition also disallows fermion superconductivity, although substantial bound state fermion currents can exist.Comment: 41 pages, 5 figure

Homeownership and Wealth in Switzerland and Germany

Property wealth represents the most important wealth component in nearly all OECD countries. Homeownership is linked to wealth accumulation in several ways: Wealthier households are more likely to buy a house or apartment, home owners tend to save more and rising house values typically yield higher returns than money in a bank account. Moreover, owners can borrow on a mortgage to finance, e.g., the formation of an enterprise or other economic activities. At the aggregate level, these relations can explain why countries with low rates of homeownership tend to have a high wealth inequality. This paper looks at wealth and homeownership in Germany and Switzerland. These countries show the lowest proportion of owner-occupiers in Europe and a high wealth inequality. We analyse to what extent this high inequality can be explained by homeownership status. In the first part of this contribution, we review explanations for the low share of owner-occupiers in the two countries. In the second part, we analyse wealth and homeownership empirically using data of the SHP and the German Socio-Economic Panel (SOEP) from 2012. We make use of decomposition methods to analyse how renter and owner households differ in wealth levels and wealth inequality