bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Oxygen Environment at Birth Specifies the Population of Alveolar Epithelial Stem Cells in the Adult Lung
Authors: Yee Min , Gelein Robert , Mariani Thomas J. , Lawrence B. Paige , O'Reilly Michael A. 
Published: February 2016

AbstractAlveolar epithelial type II cells (AEC2) maintain pulmonary homeostasis by producing surfactant, expressing innate immune molecules, and functioning as adult progenitor cells for themselves and alveolar epithelial type I cells (AEC1). How the proper number of alveolar epithelial cells is determined in the adult lung is not well understood. Here, BrdU labeling, genetic lineage tracing, and targeted expression of the anti-oxidant extracellular superoxide dismutase in AEC2s are used to show how the oxygen environment at birth influences postnatal expansion of AEC2s and AEC1s in mice. Birth into low (12%) or high (≥60%) oxygen stimulated expansion of AEC2s through self-renewal and differentiation of the airway Scgb1a1 + lineage. This non-linear or hormesis response to oxygen was specific for the alveolar epithelium because low oxygen stimulated and high oxygen inhibited angiogenesis as defined by changes in V-cadherin and PECAM (CD31). Although genetic lineage tracing studies confirmed adult AEC2s are stem cells for AEC1s, we found no evidence that postnatal growth of AEC1s were derived from self-renewing Sftpc + or the Scbg1a1 + lineage of AEC2s. Taken together, our results show how a non-linear response to oxygen at birth promotes expansion of AEC2s through two distinct lineages. Since neither lineage contributes to the postnatal expansion of AEC1s, the ability of AEC2s to function as stem cells for AEC1s appears to be restricted to the adult lung.
Concise Review: Plasma and Nuclear Membranes Convey Mechanical Information to Regulate Mesenchymal Stem Cell Lineage
Authors: Uzer Gunes , Fuchs Robyn K. , Rubin Janet , Thompson William R. 
Published: February 2016

Abstract
Numerous factors including chemical, hormonal, spatial, and physical cues determine stem cell fate. While the regulation of stem cell differentiation by soluble factors is well-characterized, the role of mechanical force in the determination of lineage fate is just beginning to be understood. Investigation of the role of force on cell function has largely focused on “outside-in” signaling, initiated at the plasma membrane. When interfaced with the extracellular matrix, the cell uses integral membrane proteins, such as those found in focal adhesion complexes to translate force into biochemical signals. Akin to these outside-in connections, the internal cytoskeleton is physically linked to the nucleus, via proteins that span the nuclear membrane. Although structurally and biochemically distinct, these two forms of mechanical coupling influence stem cell lineage fate and, when disrupted, often lead to disease. Here we provide an overview of how mechanical coupling occurs at the plasma and nuclear membranes. We also discuss the role of force on stem cell differentiation, with focus on the biochemical signals generated at the cell membrane and the nucleus, and how those signals influence various diseases. While the interaction of stem cells with their physical environment and how they respond to force is complex, an understanding of the mechanical regulation of these cells is critical in the design of novel therapeutics to combat diseases associated with aging, cancer, and osteoporosis.
Mesenchymal Stem Cells Induce Suppressive Macrophages Through Phagocytosis in a Mouse Model of Asthma
Authors: Braza Faouzi , Dirou Stéphanie , Forest Virginie , Sauzeau Vincent , Hassoun Dorian , Chesné Julie , Cheminant-Muller Marie-Aude , Sagan Christine , Magnan Antoine , Lemarchand Patricia 
Published: February 2016

Abstract
Mesenchymal stem cell (MSC) immunosuppressive functions make them attractive candidates for anti-inflammatory therapy in allergic asthma. However, the mechanisms by which they ensure therapeutic effects remain to be elucidated. In an acute mouse model of house dust mite (Der f)-induced asthma, one i.v. MSC injection was sufficient to normalize and stabilize lung function in Der f-sensitized mice as compared to control mice. MSC injection decreased in vivo airway responsiveness and decreased ex vivo carbachol-induced bronchial contraction, maintaining bronchial expression of the inhibitory type 2 muscarinic receptor. To evaluate in vivo MSC survival, MSCs were labeled with PKH26 fluorescent marker prior to i.v. injection, and 1 to 10 days later total lungs were digested to obtain single-cell suspensions. 91.5 ± 2.3% and 86.6 ± 6.3% of the recovered PKH26+ lung cells expressed specific macrophage markers in control and Der f mice, respectively, suggesting that macrophages had phagocyted in vivo the injected MSCs. Interestingly, only PKH26+ macrophages expressed M2 phenotype, while the innate PKH26− macrophages expressed M1 phenotype. Finally, the remaining 0.5% PKH26+ MSCs expressed 10- to 100-fold more COX-2 than before injection, suggesting in vivo MSC phenotype modification. Together, the results of this study indicate that MSCs attenuate asthma by being phagocyted by lung macrophages, which in turn acquire a M2 suppressive phenotype.
Concise Review: Control of Cell Fate Through Cell Cycle and Pluripotency Networks
Authors: Boward Ben , Wu Tianming , Dalton Stephen 
Published: February 2016

Abstract
Pluripotent stem cells (PSCs) proliferate rapidly with a characteristic cell cycle structure consisting of short G1- and G2-gap phases. This applies broadly to PSCs of peri-implantation stage embryos, cultures of embryonic stem cells, induced pluripotent stem cells, and embryonal carcinoma cells. During the early stages of PSC differentiation however, cell division times increase as a consequence of cell cycle remodeling. Most notably, this is indicated by elongation of the G1-phase. Observations linking changes in the cell cycle with exit from pluripotency have raised questions about the role of cell cycle control in maintenance of the pluripotent state. Until recently however, this has been a difficult question to address because of limitations associated with experimental tools. Recent studies now show that pluripotency and cell cycle regulatory networks are intertwined and that cell cycle control mechanisms are an integral, mechanistic part of the PSC state. Studies in embryonal carcinoma, some 30 years ago, first suggested that pluripotent cells initiate differentiation when in the G1-phase. More recently, a molecular “priming” mechanism has been proposed to explain these observations in human embryonic stem cells. Complexity in this area has been increased by the realization that pluripotent cells exist in multiple developmental states and that in addition to each having their own characteristic gene expression and epigenetic signatures, they potentially have alternate modes of cell cycle regulation. This review will summarize current knowledge in these areas and will highlight important aspects of interconnections between the cell cycle, self-renewal, pluripotency, and cell fate decisions.
Modification of the simplified method of crack control included in EN 1992‐3
Authors: Zych Mariusz 
Published: February 2016

AbstractThe methods of crack control for liquid‐retaining RC tank walls are analysed taking into account external load (EN 1992‐1‐1) and imposed strain occurring at the construction stage (EN 1992‐3), i.e. during the concrete‐hardening period. The convergence ranges of the s implified method of crack control included in EN 1992‐3 and the detailed calculation methods included in EN 1992‐1‐1 and EN 1992‐3 are defined. Apart from the compatibility areas, overestimation of the acceptable reinforcing bar diameter φs*, illustrated in Fig. 7.103N in EN 1992‐3, was proved. Coefficients kφ1 and kφ2 are defined, which enable the calculation of the acceptable reinforcing bar diameter φs* in order to obtain the values complying with the direct calculations. For practical purposes, graphs have been plotted to facilitate the definition of coefficients kφ1 and kφ2 without performing direct calculations. On the basis of the analyses performed and the relations proposed, it can be concluded that there is a possibility or a necessity to increase or decrease the acceptable reinforcing bar diameter φs* depending on the concrete mechanical properties and geometrical properties of an RC tank wall.
The structural redistribution coefficient KRd: a numerical approach to its evaluation
Authors: di Prisco Marco , Martinelli Paolo , Dozio Daniele 
Published: February 2016

AbstractStructures made of a material with a very high standard deviation, such as fibre‐reinforced concrete, exhibit an exceptionally safe prediction of the maximum bearing capacity when this is derived from characteristic values identified by means of small specimens. This is emphasized when the structures are characterized by high redundancy. In this regard, two reference tests representing two extreme situations are considered: a) simply supported unnotched full‐scale beams characterized by a statically determinate loading scheme and b) full‐scale slabs on the ground characterized by a statically indeterminate loading scheme. The Italian standard and, more recently, the fib Model Code for Concrete Structures 2010 have introduced a coefficient (structural redistribution factor) that is able to take into account the reduced variability of mechanical bearing capacity when associated with a large volume involved in the failure process and/or when the structure is able to redistribute stresses significantly, thus favouring the average rather than the minimum strength. A numerical procedure taking into account the expected heterogeneity of the mechanical characteristics in the structure is introduced for the first time to evaluate the redistribution factor.
Derivation of design rules for innovative shear connectors in steel‐concrete composites through the systematic use of non‐linear finite element analysis (FEA)
Authors: Classen Martin , Herbrand Martin , Kueres Dominik , Hegger Josef 
Published: February 2016

AbstractToday, the development of innovative shear connectors for steel‐concrete composites is accompanied by a large number of experimental investigations, which are obligatory when proposing suitable design formula and carving out their limitations of use. Using the example of the so‐called pin connector, the present paper illustrates to what extent validated finite element models of novel shear connectors can be used to replace expensive and time‐consuming shear tests and how these finite element models can support the deduction of design concepts. The pin connector considered was developed for connecting steel sections to very slender high‐strength concrete slabs in which conventional shear connectors such as headed studs cannot be used due to the limited embedment depth. In order to clarify the shear behaviour and load‐carrying mechanisms of these novel connectors, non‐linear finite element models were set up using the commercial FE software Abaqus. Subsequently, the FE models were used to perform systematic parametric studies. This paper describes the numerical results and also explains the stepwise development of an entire engineering model for determining the longitudinal shear capacity of small‐scale pin connectors, including all the necessary limitations of use. The proposed modelling strategy and the methodology for the deduction of design rules can be transferred and assigned to other types of shear connectors.
Development of stiffness and ultrasonic pulse velocity of fatigue loaded concrete
Authors: von der Haar Christoph , Marx Steffen 
Published: February 2016

AbstractDamage processes in fatigue loaded concrete structures depend on the number and amplitude of the load cycles applied. Damage evolution is linked to a reduction in concrete stiffness, and it is thought that this reduction causes stress redistributions at component level which have a favourable impact on the service life of a structure. Until now, the stiffness reduction and stress redistribution have never been successfully measured in laboratory tests or in situ. It is only known that the real service life is longer than the calculated one and that indicators of stiffness reduction, such as component deflection, increase with the number of load cycles applied.Ultrasonic measurement techniques are considered to be well suited to detecting degradation processes caused by cyclic loading. It is expected that the stiffness reduction in fatigue loaded concrete structures can be recorded reliably with ultrasonic pulse velocity measurements. In the light of this, fatigue tests were performed on small‐scale concrete specimens. The aims of the tests were to understand the correlation between the observed stiffness degradation of the specimens and the results of ultrasonic pulse velocity measurements and to estimate the potential for using ultrasonic pulse velocity measurements in continuous structural health monitoring.
Power allocation, relay selection and energy cooperation strategies in energy harvesting cooperative wireless networks
Authors: Baidas Mohammed W. , Alsusa Emad A. 
Published: February 2016

AbstractIn this paper, optimal power allocation and relay selection strategies in energy harvesting cooperative wireless networks are studied. In particular, signal‐to‐noise ratio (SNR)‐maximizing based power allocation and relay selection without and with energy cooperation—via wireless energy transfer—are considered. Moreover, total relay power minimization subject to target end‐to‐end SNR is investigated. The different optimal strategies are formulated as optimization problems, which are non‐convex. Thus, intelligent transformations are applied to transform non‐convex problems into convex ones, and polynomial‐time solution procedures are proposed. Simulation results illustrate that power allocation strategies achieve higher end‐to‐end SNR than relay selection ones. Finally, energy cooperation is shown to be effective in improving end‐to‐end SNR, while total relay power minimization balances end‐to‐end SNR, transmit power consumption, and harvested energy. Copyright © 2016 John Wiley & Sons, Ltd.
Achieving energy‐neutral data transmission by adjusting transmission power for energy‐harvesting wireless sensor networks
Authors: Tan Qian , An Wei , Han Yanni , Luo Haiyan , Liu Yanwei , Ci Song , Tang Hui 
Published: February 2016

AbstractRecently, benefiting from rapid development of energy harvesting technologies, the research trend of wireless sensor networks has shifted from the battery‐powered network to the one that can harvest energy from ambient environments. In such networks, a proper use of harvested energy poses plenty of challenges caused by numerous influence factors and complex application environments. Although numerous works have been based on the energy status of sensor nodes, no work refers to the issue of minimizing the overall data transmission cost by adjusting transmission power of nodes in energy‐harvesting wireless sensor networks. In this paper, we consider the optimization problem of deriving the energy‐neutral minimum cost paths between the source nodes and the sink node. By introducing the concept of energy‐neutral operation, we first propose a polynomial‐time optimal algorithm for finding the optimal path from a single source to the sink by adjusting the transmission powers. Based on the work earlier, another polynomial‐time algorithm is further proposed for finding the approximated optimal paths from multiple sources to the sink node. Also, we analyze the network capacity and present a near‐optimal algorithm based on the Ford–Fulkerson algorithm for approaching the maximum flow in the given network. We have validated our algorithms by various numerical results in terms of path capacity, least energy of nodes, energy ratio, and path cost. Simulation results show that the proposed algorithms achieve significant performance enhancements over existing schemes. Copyright © 2016 John Wiley & Sons, Ltd.
Transmit antenna selection of correlated MIMO multiuser cognitive radio networks in Nakagami‐m fading channels
Authors: Abd El‐Malek Ahmed H. , Al‐Qahtani Fawaz S. , Zummo Salam A. , Alnuweiri Hussein 
Published: February 2016

AbstractIn this paper, we examine the impact of antenna correlation on transmit antenna selection with receive maximal ratio combining (TAS/MRC) in multiple‐input multiple‐output multiuser underlay cognitive radio network (MIMO‐MCN) over a Nakagami‐m fading environment. The secondary network under consideration consists of a single source and M destinations equipped with multiple correlated antennas at each node. The primary network composed of L primary users, each of which is equipped with multiple correlated antennas. For the considered underlay spectrum sharing paradigm, the transmission power of the proposed secondary system is limited by the peak interference limit on the primary network and the maximum transmission power at the secondary network. In particular, we derive exact closed‐form expressions for the outage probability and average symbol error rate of the proposed secondary system. To gain further insights, simple asymptotic closed‐form expressions for the outage probability and symbol error rate are provided to obtain the achievable diversity order and coding gain of the system. In addition, the impact of antenna correlation on the secondary user ergodic capacity has been investigated by deriving closed‐form expressions for the secondary user capacity. The derived analytical formulas herein are supported by numerical and simulation results to clarify the main contributions. Copyright © 2016 John Wiley & Sons, Ltd.
Higher Acetabular Anteversion in Direct Anterior Total Hip Arthroplasty: A Retrospective Case-Control Study
Authors: Chen Antonia F. , Chen Chi-Lung , Low Sara , Lin Wei-Ming , Chinnakkannu Karthikeyan , Orozco Fabio R. , Ong Alvin C. , Post Zachary D. 
Published: February 2016

Background Surgical approach is known as a risk factor that influences cup malposition while performing total hip arthroplasty (THA). However, no study has been conducted comparing cup positioning between the supine direct anterior (DA) and supine direct lateral (DL) THA approaches. Questions/Purposes (1) Is there a difference in acetabular cup positioning between supine DA and supine DL THA approaches? (2) Are there differences in complications based on acetabular cup positioning between the two approaches? Methods From 2012 to 2014, 186 patients who underwent primary THAs using DA approach were matched with 186 patients using DL approach by body mass index, age, and gender. Cup anteversion and abduction angles were measured from standing anteroposterior pelvis radiographs by two blinded observers. The Lewinnek safe zone was used as the standard for cup positioning. Cup anteversion, abduction angles, and complications were recorded and compared. Results Cup anteversion was on average 3° higher in the DA approach compared to the DL approach. The abduction angle for the DA approach was equivalent to the DL approach both averaging 46° to 47°. There were more DA hips outside of the safe zone (10%) for anteversion than DL (3%) hips. There were no differences in complications between DA and DL approaches. Conclusion There is a tendency to antevert the acetabular cup when performing THAs using the DA approach, and one must be mindful of this when implanting the acetabular component.
Bioactive Compounds in Virgin Olive Oil of the PDO Montoro‐Adamuz
Authors: Romero C. , Ruiz‐Méndez Mª. V. , Brenes Manuel 
Published: February 2016

AbstractVirgin olive oil (VOO) is generally recognized as a healthy fat because of its fatty acid composition and content in minor compounds but a wide range of these substances can be found in commercial oils. The concentration of compounds with attributed health benefits were analyzed in VOO of the PDO Montoro‐Adamuz. Oleic acid represented around 79 % of the total fatty acids, and the mean squalene and tocopherols concentrations were 5800 and 247 mg/kg respectively. Despite the changes found in polyphenols concentration in the oils analyzed for six consecutive crops, these substances accounted for more than 700 mg/kg. Moreover, the effect of irrigation regime and sun radiation on the content in bioactive substances of these oils was also assessed. No significant differences were detected between oils from trees irrigated ad libitum or rain‐feed. In contrast, the level of tree radiation exerted a great effect on the concentration of bioactive substances in oils. Oils from trees cultivated in a sunny area (south orientation) had a higher percentage of oleic acid and concentration in phenolic compounds than those from shady areas (north orientation). The opposite was detected for tocopherols and squalene which were more concentrated in oils from olives of the shady area. The results obtained in this study point out VOO of the PDO Montoro‐Adamuz as a very healthy fat due to their composition in bioactive substances, in particular their richness in phenolic compounds.
Evaluating the Talent Search TRIO program: A Benefit-Cost Analysis and Cost-Effectiveness Analysis
Authors: Bowden A. Brooks , Belfield Clive 
Published: February 2016

Talent Search was created to improve high school completion and college enrollment for disadvantaged students. Since the program’s inception in 1967, there has not been a valid study on its economic value. In this paper, we perform a full economic evaluation, yielding direct information on the value of Talent Search and highlighting key methodological issues relating to economic evaluations of education programs. We provide rigorous estimates of social costs using the ingredients method. Using prior estimates of impacts from Constantine et al. [(2006). Study Of The Effect of The Talent Search Program On Secondary And Postsecondary Outcomes In Florida, Indiana And Texas: Final Report From Phase II of The National Evaluation. Washington, DC: U.S. Department of Education Office of Planning, Evaluation and Policy Development, Policy and Program Studies Service], we perform a cost-benefit analysis based on new estimates of shadow prices. Finally, to examine site-specific differences in impacts and costs, we undertake cost-effectiveness analysis and derive confidence intervals that illustrate key sensitivity issues. Regarding costs, we find significant resource use beyond federal funding amounts; but we also find that the present value benefits of Talent Search almost certainly exceed the present value of costs by a substantial margin. With regard to cost-effectiveness, we find significant differences across sites and extremely wide confidence intervals. We conclude with an outline of key research issues that need to be addressed to enhance future economic evaluations in educational settings with wide site-specific variation.