Miracle-dz/UniFAR-FTUs huggingface dataset:
A multi-channel mac protocol for ad hoc wireless networks

This paper proposes a medium access control (MAC) protocol for ad hoc wireless networks that can utilize multiple channels dynamically to improve performance. IEEE 802.11 standard provides multiple channels for use, but its MAC protocol is designed only for a single channel. We can achieve imp roved throughput with multiple channels because multiple transmissions can take place simultaneously without interfering each other. We modify IEEE 802.11 DCF protocol to enable hosts to utilize multiple channels by switching channels dynamically. Our scheme requires only one transceiver for each host. The main idea is to use ATIM windows as in power saving mechanism (PSM) of IEEE 802.11 DCF, so that hosts can negotiate and select channels during the window using ATIM messages. Our scheme imp roves throughput of the network significantly, especially when the network is highly congested. We have simulated our protocol to verify its performance compared to IEEE 802.11 and another multi-channel MAC protocol. The results show that our protocol performs better than both. The improvement over the existing multi-channel MAC protocol is obtained even though our protocol uses simpler hardware.
Distribution of LDL particle size in a population-based sample of children and adolescents and relationship with other cardiovascular risk factors.

BACKGROUND Smaller, denser LDL particles are associated with an increased risk for cardiovascular diseases (CVD). In youths, data on the distribution of LDL particle size and on its association with other CVD risk factors are limited. METHODS We determined LDL peak particle size by nondenaturing 2%-16% gradient gel electrophoresis in a representative sample of 2249 youths 9, 13, and 16 years of age who participated in a school-based survey conducted in 1999 in the province of Quebec, Canada. Standardized clinical measurements and fasting plasma lipid, glucose, and insulin concentrations were available. RESULTS The LDL peak particle size distribution was gaussian. The 5th, 50th (median), and 95th percentiles by age and sex were 255.5-258.6, 262.1-263.2, and 268.1-269.5 A, respectively. The prevalence of the small, dense LDL phenotype (LDL peak particle size <or=255 A) was 10% in participants with insulin resistance syndrome (IRS), in contrast to 1% in those without IRS. In a multiple regression analysis, the association of LDL size with other CVD risk factors [apolipoprotein B, HDL-cholesterol (HDL-C), triglyceride (TG), and insulin concentrations, and body mass index] was strongest with TG and HDL-C concentrations: a 1 SD increase in log(e)-transformed TG concentration was associated with a 1.2 A reduction in LDL size, and a 1 SD increase in HDL-C was associated with a 1.1 A increase in LDL size. CONCLUSIONS Although the small, dense LDL phenotype is less prevalent in youths than adults, its prevalence is clearly increased in childhood IRS. Metabolic correlates of LDL size are similar in youths and adults.
Mapping Condition-Dependent Regulation of Lipid Metabolism in Saccharomyces cerevisiae

Lipids play a central role in cellular function as constituents of membranes, as signaling molecules, and as storage materials. Although much is known about the role of lipids in regulating specific steps of metabolism, comprehensive studies integrating genome-wide expression data, metabolite levels, and lipid levels are currently lacking. Here, we map condition-dependent regulation controlling lipid metabolism in Saccharomyces cerevisiae by measuring 5636 mRNAs, 50 metabolites, 97 lipids, and 57 13C-reaction fluxes in yeast using a three-factor full-factorial design. Correlation analysis across eight environmental conditions revealed 2279 gene expression level-metabolite/lipid relationships that characterize the extent of transcriptional regulation in lipid metabolism relative to major metabolic hubs within the cell. To query this network, we developed integrative methods for correlation of multi-omics datasets that elucidate global regulatory signatures. Our data highlight many characterized regulators of lipid metabolism and reveal that sterols are regulated more at the transcriptional level than are amino acids. Beyond providing insights into the systems-level organization of lipid metabolism, we anticipate that our dataset and approach can join an emerging number of studies to be widely used for interrogating cellular systems through the combination of mathematical modeling and experimental biology.
Rechts-, Wirtschafts-und Verwaltungswissenschaftliche Sektion Fachbereich Wirtschaftswissenschaften Diskussionspapiere Der Dfg- Forschergruppe (nr.: 3468269275): Heterogene Arbeit: Positive Und Normative Aspekte Der Qualifikationsstruktur Der Arbeit Diskussionspapier Der Forschergruppe (nr.: 3468269

Zusammenfassung: In a two-period model with agent heterogeneity we analyze a pension reform toward a stronger link between contributions and benefits (as recently observed in several countries) in a pension system with a Bismarckian and a Beveridgian component. We show that such a policy change reduces the educational level in an economy. The life expectancy differential between skilled and unskilled individuals drives this result. Furthermore, we investigate the consequences on the intragenerational redistribution characteristics of the pension system – in the sense of the number of net-recipients relative to net-payers – as well as welfare effects. Abstract In a two-period model with agent heterogeneity we analyze a pension reform toward a stronger link between contributions and benefits (as recently observed in several countries) in a pension system with a Bismarckian and a Beveridgian component. We show that such a policy change reduces the educational level in an economy. The life expectancy differential between skilled and unskilled individuals drives this result. Furthermore, we investigate the consequences on the intragenerational redistribution characteristics of the pension system – in the sense of the number of net-recipients relative to net-payers – as well as welfare effects.
Polarized Submillimeter Emission from Filamentary Molecular Clouds

We model the submillimeter polarization patterns that are expected for filamentary clouds that are threaded by helical magnetic fields. We previously developed a three-parameter model of such clouds, which are described by a concentration parameter C and two flux-to-mass ratios Γz and Γϕ to specify the mass loading of the poloidal and toroidal field lines, respectively. Our models provide a simple and purely geometric explanation for the well-known "polarization hole" effect, in which the submillimeter polarization percentage decreases toward the regions of peak intensity. This occurs because of a cancellation between contributions to the polarization from the "backbone" of poloidal flux along the filament's axis and its surrounding envelope, which is dominated by the toroidal field component. A systematic exploration of our parameter space allows us to classify the polarization patterns due to filaments aligned approximately perpendicular to the plane of the sky into three basic types. The polarization vectors are parallel to filaments when Bz,S/Bϕ,S ≲ 0.1, where Bz,S and Bϕ,S are, respectively, the poloidal and toroidal magnetic field components at the outer surface of the filament. The polarization vectors are perpendicular to filaments when Bz,S/Bϕ,S ≳ 0.37. Intermediate cases result in polarization patterns that contain 90° flips in the orientation of the polarization vectors. The flips are symmetric about the central axis for filaments oriented parallel to the plane of the sky, but more complicated asymmetric patters result from filaments that are inclined at some angle.
Use of Social Media Across US Hospitals: Descriptive Analysis of Adoption and Utilization

Background Use of social media has become widespread across the United States. Although businesses have invested in social media to engage consumers and promote products, less is known about the extent to which hospitals are using social media to interact with patients and promote health. Objective The aim was to investigate the relationship between hospital social media extent of adoption and utilization relative to hospital characteristics. Methods We conducted a cross-sectional review of hospital-related activity on 4 social media platforms: Facebook, Twitter, Yelp, and Foursquare. All US hospitals were included that reported complete data for the Centers for Medicare and Medicaid Services Hospital Consumer Assessment of Healthcare Providers and Systems survey and the American Hospital Association Annual Survey. We reviewed hospital social media webpages to determine the extent of adoption relative to hospital characteristics, including geographic region, urban designation, bed size, ownership type, and teaching status. Social media utilization was estimated from user activity specific to each social media platform, including number of Facebook likes, Twitter followers, Foursquare check-ins, and Yelp reviews. Results Adoption of social media varied across hospitals with 94.41% (3351/3371) having a Facebook page and 50.82% (1713/3371) having a Twitter account. A majority of hospitals had a Yelp page (99.14%, 3342/3371) and almost all hospitals had check-ins on Foursquare (99.41%, 3351/3371). Large, urban, private nonprofit, and teaching hospitals were more likely to have higher utilization of these accounts. Conclusions Although most hospitals adopted at least one social media platform, utilization of social media varied according to several hospital characteristics. This preliminary investigation of social media adoption and utilization among US hospitals provides the framework for future studies investigating the effect of social media on patient outcomes, including links between social media use and the quality of hospital care and services.
α-tomatine inhibits growth and induces apoptosis in HL-60 human myeloid leukemia cells

α-tomatine is a glycoalkaloid that occurs naturally in tomatoes (Lycopersicon esculentum). In the present study, the effects of α-tomatine on human myeloid leukemia HL-60 cells were investigated. Treatment of HL-60 cells with α-tomatine resulted in growth inhibition and apoptosis in a concentration-dependent manner. Tomatidine, the aglycone of tomatine had little effect on the growth and apoptosis of HL-60 cells. Growth inhibition and apoptosis induced by α-tomatine in HL-60 cells was partially abrogated by addition of cholesterol indicating that interactions between α-tomatine and cell membrane-associated cholesterol may be important in mediating the effect of α-tomatine. Activation of nuclear factor-κB by the phorbol ester, 12-O-tetradecanoylphorbol-13-acetate failed to prevent apoptosis in HL-60 cells treated with α-tomatine. In animal experiments, it was found that treatment of mice with α-tomatine inhibited the growth of HL-60 xenografts in vivo. Results from the present study indicated that α-tomatine may have useful anti-leukemia activities.
Males Have Larger Skeletal Size and Bone Mass Than Females, Despite Comparable Body Size

Gender differences in fractures may be related to body size, bone size, geometry, or density. We studied this in 18‐year‐old males (n = 36) and females (n = 36) matched for height and weight. Despite comparable body size, males have greater BMC and BMD at the hip and distal tibia and greater tibial cortical thickness. This may confer greater skeletal integrity in males.
High rates of fuel consumption are not required by insulating motifs to suppress retroactivity in biochemical circuits

Retroactivity arises when the coupling of a molecular network $\mathcal{U}$ to a downstream network $\mathcal{D}$ results in signal propagation back from $\mathcal{D}$ to $\mathcal{U}$. The phenomenon represents a breakdown in modularity of biochemical circuits and hampers the rational design of complex functional networks. Considering simple models of signal-transduction architectures, we demonstrate the strong dependence of retroactivity on the properties of the upstream system, and explore the cost and efficacy of fuel-consuming insulating motifs that can mitigate retroactive effects. We find that simple insulating motifs can suppress retroactivity at a low fuel cost by coupling only weakly to the upstream system $\mathcal{U}$. However, this design approach reduces the signalling network's robustness to perturbations from leak reactions, and potentially compromises its ability to respond to rapidly-varying signals.
Risk of Burnout in Perioperative Clinicians: A Survey Study and Literature Review

Background: Burnout can lead to health and psychologic problems and is apparently increasing in physicians and nurses. Previous studies have not evaluated all healthcare workers within a single work unit. This study evaluates the risk of burnout in all medical personnel in one perioperative unit. Methods: We developed an online survey that included demographics, a modified version of the Maslach Burnout Inventory–Human Services Survey, and the Social Support and Personal Coping Survey. Survey constructs (e.g., depersonalization and health) and a global score were calculated. Larger construct and global values were associated with higher risk of burnout. These were separately regressed on role, age, and sex. The global score was then regressed on each of the survey constructs. Results: Of the 145 responses, 46.2% were physicians (22.8% residents), 43.4% were nurses or nurse anesthetists, and 10.3% were other personnel. After adjusting for sex and age, residents scored higher than other physicians on the following (expected change [95% confidence interval]): global score (1.12 [0.43–1.82]), emotional exhaustion (1.54 [0.44–2.60]), and depersonalization (1.09 [0.23–1.95]). Compared with nonphysicians, residents were 1 U or more higher on these items (P < 0.05 in all cases). Residents had higher health (1.49 [0.48–2.50]) and workload (1.23 [0.07–2.40]) values compared with physicians. Better health, personal support, and work satisfaction scores were related to decreased global scores (P < 0.05). Conclusions: Physicians (particularly residents) had the largest global burnout scores, implying increased risk of burnout. Improving overall health, increasing personal support, and improving work satisfaction may decrease burnout among perioperative team members.
Widespread microglial activation in patients deceased from traumatic brain injury

Abstract Primary objective: The role of microglial activation in traumatic brain injury (TBI) has been extensively described in established animal models. In contrast, very few studies have analysed this process in human patients, the majority being focused on the local reaction in the contused parenchyma. In this work, the main objective was the analysis of microglial activation in brain regions distant from the primary lesion. Research design: Morphological changes of microglia were evaluated in the cerebral cortex of patients deceased from TBI in comparison with control subjects. Methods and procedures: Cortical samples from five cases with TBI and 10 controls were evaluated using Ricinus communis lectin histochemistry and conventional Hematoxylin-eosin staining. Main outcomes and results: It was observed that microglial cells from patients with TBI presented shorter and thicker cellular projections compared with controls. Moreover, the percentage of histological area reactive to lectin was statistically higher in samples from subjects with TBI. These signs of microglial activation were observed in all of the analysed cortical areas, thus indicating a generalized effect on the whole cerebral cortex. The results are consistent with previous imaging PET studies performed in living patients with the 11C-PK11195 radiotracer. Conclusions: The findings indicate that TBI induces a widespread activation of brain microglia which affects all cortical areas, including those distant from the contusion site.
Nkx3.2 Promotes Primary Chondrogenic Differentiation by Upregulating Col2a1 Transcription

Background The Nkx3.2 transcription factor promotes chondrogenesis by forming a positive regulatory loop with a crucial chondrogenic transcription factor, Sox9. Previous studies have indicated that factors other than Sox9 may promote chondrogenesis directly, but these factors have not been identified. Here, we test the hypothesis that Nkx3.2 promotes chondrogenesis directly by Sox9-independent mechanisms and indirectly by previously characterized Sox9-dependent mechanisms. Methodology/Principal Findings C3H10T1/2 pluripotent mesenchymal cells were cultured with bone morphogenetic protein 2 (BMP2) to induce endochondral ossification. Overexpression of wild-type Nkx3.2 (WT-Nkx3.2) upregulated glycosaminoglycan (GAG) production and expression of type II collagen α1 (Col2a1) mRNA, and these effects were evident before WT-Nkx3.2-mediated upregulation of Sox9. RNAi-mediated inhibition of Nkx3.2 abolished GAG production and expression of Col2a1 mRNA. Dual luciferase reporter assays revealed that WT-Nkx3.2 upregulated Col2a1 enhancer activity in a dose-dependent manner in C3H10T1/2 cells and also in N1511 chondrocytes. In addition, WT-Nkx3.2 partially restored downregulation of GAG production, Col2 protein expression, and Col2a1 mRNA expression induced by Sox9 RNAi. ChIP assays revealed that Nkx3.2 bound to the Col2a1 enhancer element. Conclusions/Significance Nkx3.2 promoted primary chondrogenesis by two mechanisms: Direct and Sox9-independent upregulation of Col2a1 transcription and upregulation of Sox9 mRNA expression under positive feedback system.
Cotton Nonwovens as Oil Spill Cleanup Sorbents

We examined partial or complete replacement of synthetic sorbents by cotton- containing nonwovens for use in oil spill cleanup. The results indicate that with light crude oil, oil sorption capacities of the needlepunched cotton-containing sorbents were slightly greater than those of sorbents made from 100% polypropylene fibers. If necessary, a small portion of polypropylene fiber could be incorporated into nonwovens to increase mechanical strength properties and to maintain fabric integrity. The cotton- containing sorbents were reusable after a simple mechanical compression to remove oil. They also floated in an artificial seawater bath for a long period of time. We found that oil sorption of cotton fiber was controlled by adsorption on the fiber surface and capillary action through its lumen. Contrarily, the main mechanism for polypropylene was through capillary bridges between fibers. Detailed evaluation using an environ mental scanning electron microscope confirmed this mechanism. Individual bundles of both cotton and polypropylene fibers sorbed more oil than did the needlepunched nonwoven fabrics prepared from the respective fibers. In addition, sorption decreased as needling density increased. This study provides preliminary data for investigating other cotton nonwoven constructions with improved oil sorption properties.
The detection of the periodic structure of high-angle twist boundaries: II. High resolution electron microscopy study

High resolution electron microscopy was used to image directly the 0-lattice of <001> twist boundaries with mis-o orientations up to 25° and 0-lattice spacings as small as 7A. The results were entirely consistent i^ith the conclusions reached on the basis of the diffraction experiments described as Part I. An experimental method was devised for determining whether the 0-lattice was imaged by conventional diffraction strain contrast or by interference strain contrast xvhich arises from interference between f.c. c. and 0-reflections resulting from the periodic structure of the boundary (Part I). It was o demonstrated that spacings down to about 34A were imaged mainly by means of diffraction strain contrast, while networks o with spacings of about 16A or less were imaged mainly by means of interference strain contrast. Efforts were also made to detect secondary grain boundary dislocation networks and such networks were observed in the vicinity of S=5, 13 and 17 bound aries over a larger range of misorientations than detected previously.
NEW RESULTS ON THE NON-LINEARITY AND THE SENSITIVITY OF THE ESTIMATION OF THE DIFFUSION COEFFICIENT IN A 2D ELLIPTIC EQUATION

We consider the problem of determining the diffusion coefficient a x in a 2D elliptic equation from a distributed measurement z in H 1 of the solution u of the equation. For a problem with a simple geometry, we give conditions under which the first derivative of the b 1 a u mapping is coercive. Then we show that its non linearity in a direction d increases, and its sensitivity decreases, when the ratio ∇ d b L2 d b L2 increases. This corroborates observations on scale, sensitivity and non linearity made in (Chavent and Liu, 89) (Grimstad and Mannseth, 99).
A Class I ADP-Ribosylation Factor GTPase-Activating Protein Is Critical for Maintaining Directional Root Hair Growth in Arabidopsis1[W][OA]

Membrane trafficking and cytoskeletal dynamics are important cellular processes that drive tip growth in root hairs. These processes interact with a multitude of signaling pathways that allow for the efficient transfer of information to specify the direction in which tip growth occurs. Here, we show that AGD1, a class I ADP ribosylation factor GTPase-activating protein, is important for maintaining straight growth in Arabidopsis (Arabidopsis thaliana) root hairs, since mutations in the AGD1 gene resulted in wavy root hair growth. Live cell imaging of growing agd1 root hairs revealed bundles of endoplasmic microtubules and actin filaments extending into the extreme tip. The wavy phenotype and pattern of cytoskeletal distribution in root hairs of agd1 partially resembled that of mutants in an armadillo repeat-containing kinesin (ARK1). Root hairs of double agd1 ark1 mutants were more severely deformed compared with single mutants. Organelle trafficking as revealed by a fluorescent Golgi marker was slightly inhibited, and Golgi stacks frequently protruded into the extreme root hair apex of agd1 mutants. Transient expression of green fluorescent protein-AGD1 in tobacco (Nicotiana tabacum) epidermal cells labeled punctate bodies that partially colocalized with the endocytic marker FM4-64, while ARK1-yellow fluorescent protein associated with microtubules. Brefeldin A rescued the phenotype of agd1, indicating that the altered activity of an AGD1-dependent ADP ribosylation factor contributes to the defective growth, organelle trafficking, and cytoskeletal organization of agd1 root hairs. We propose that AGD1, a regulator of membrane trafficking, and ARK1, a microtubule motor, are components of converging signaling pathways that affect cytoskeletal organization to specify growth orientation in Arabidopsis root hairs.
Case–Control Studies of Gene–Environment Interaction: Bayesian Design and Analysis

Summary With increasing frequency, epidemiologic studies are addressing hypotheses regarding gene‐environment interaction. In many well‐studied candidate genes and for standard dietary and behavioral epidemiologic exposures, there is often substantial prior information available that may be used to analyze current data as well as for designing a new study. In this article, first, we propose a proper full Bayesian approach for analyzing studies of gene–environment interaction. The Bayesian approach provides a natural way to incorporate uncertainties around the assumption of gene–environment independence, often used in such an analysis. We then consider Bayesian sample size determination criteria for both estimation and hypothesis testing regarding the multiplicative gene–environment interaction parameter. We illustrate our proposed methods using data from a large ongoing case–control study of colorectal cancer investigating the interaction of N‐acetyl transferase type 2 (NAT2) with smoking and red meat consumption. We use the existing data to elicit a design prior and show how to use this information in allocating cases and controls in planning a future study that investigates the same interaction parameters. The Bayesian design and analysis strategies are compared with their corresponding frequentist counterparts.