bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observation-Based Longwave Cloud Radiative Kernels Derived from the A-Train
Authors: Yue Qing , Kahn Brian H. , Fetzer Eric J. , Schreier Mathias , Wong Sun , Chen Xiuhong , Huang Xianglei 
Published: January 2016

Abstract
The authors present a new method to derive both the broadband and spectral longwave observation-based cloud radiative kernels (CRKs) using cloud radiative forcing (CRF) and cloud fraction (CF) for different cloud types using multisensor A-Train observations and MERRA data collocated on the pixel scale. Both observation-based CRKs and model-based CRKs derived from the Fu–Liou radiative transfer model are shown. Good agreement between observation- and model-derived CRKs is found for optically thick clouds. For optically thin clouds, the observation-based CRKs show a larger radiative sensitivity at TOA to cloud-cover change than model-derived CRKs. Four types of possible uncertainties in the observed CRKs are investigated: 1) uncertainties in Moderate Resolution Imaging Spectroradiometer cloud properties, 2) the contributions of clear-sky changes to the CRF, 3) the assumptions regarding clear-sky thresholds in the observations, and 4) the assumption of a single-layer cloud. The observation-based CRKs show the TOA radiative sensitivity of cloud types to unit cloud fraction change as observed by the A-Train. Therefore, a combination of observation-based CRKs with cloud changes observed by these instruments over time will provide an estimate of the short-term cloud feedback by maintaining consistency between CRKs and cloud responses to climate variability.
Characterizing Recent Trends in U.S. Heavy Precipitation
Authors: Hoerling Martin , Eischeid Jon , Perlwitz Judith , Quan Xiao-Wei , Wolter Klaus , Cheng Linyin 
Published: January 2016

Abstract
Time series of U.S. daily heavy precipitation (95th percentile) are analyzed to determine factors responsible for regionality and seasonality in their 1979–2013 trends. For annual conditions, contiguous U.S. trends have been characterized by increases in precipitation associated with heavy daily events across the northern United States and decreases across the southern United States. Diagnosis of climate simulations (CCSM4 and CAM4) reveals that the evolution of observed sea surface temperatures (SSTs) was a more important factor influencing these trends than boundary condition changes linked to external radiative forcing alone. Since 1979, the latter induces widespread, but mostly weak, increases in precipitation associated with heavy daily events. The former induces a meridional pattern of northern U.S. increases and southern U.S. decreases as observed, the magnitude of which closely aligns with observed changes, especially over the south and far west. Analysis of model ensemble spread reveals that appreciable 35-yr trends in heavy daily precipitation can occur in the absence of forcing, thereby limiting detection of the weak anthropogenic influence at regional scales.
Analysis of the seasonality in heavy daily precipitation trends supports physical arguments that their changes during 1979–2013 have been intimately linked to internal decadal ocean variability and less so to human-induced climate change. Most of the southern U.S. decrease has occurred during the cold season that has been dynamically driven by an atmospheric circulation reminiscent of teleconnections linked to cold tropical eastern Pacific SSTs. Most of the northeastern U.S. increase has been a warm season phenomenon, the immediate cause for which remains unresolved.
Tropospheric and Stratospheric Precursors to the January 2013 Sudden Stratospheric Warming
Authors: Attard Hannah E. , Rios-Berrios Rosimar , Guastini Corey T. , Lang Andrea L. 
Published: January 2016

AbstractThis paper investigates the tropospheric and stratospheric precursors to a major sudden stratospheric warming (SSW) that began on 6 January 2013. Using the Climate Forecast System Reanalysis dataset, the analysis identified two distinct decelerations of the 10-hPa zonal mean zonal wind at 65°N in December in addition to the major SSW, which occurred on 6 January 2013 when the 10-hPa zonal mean zonal wind at 65°N reversed from westerly to easterly. The analysis shows that the two precursor events preconditioned the stratosphere for the SSW.Analysis of the tropospheric state in the days leading to the precursor events and the major SSW suggests that high-latitude tropospheric blocks occurred in the days prior to the two December deceleration events, but not in the days prior to the SSW. A detailed wave activity flux (WAF) analysis suggests that the tropospheric blocking prior to the two December deceleration events contributed to an anomalously positive 40-day-average 100-hPa zonal mean meridional eddy heat flux prior to the SSW. Analysis of the stratospheric structure in the days prior to the SSW reveals that the SSW was associated with enhanced WAF in the upper stratosphere, planetary wave breaking, and an upper-stratospheric/lower-mesospheric disturbance. These results suggest that preconditioning of the stratosphere occurred as a result of WAF initiated by tropospheric blocking associated with the two December deceleration events. The two December deceleration events occurred in the 40 days prior to the SSW and led to the amplification of wave activity in the upper stratosphere and wave resonance that caused the January 2013 SSW.
Regulation of Assisted Reproductive Technologies: Gains and Losses
Authors: Chakravarthi Indira 
Published: January 2016

Technology assessment and regulatory strategies have been proffered as ways of addressing concerns and problems arising from availability of certain medical technologies. Regulation especially is invoked as a remedy that can deliver several objectives—as a way of assuring quality care; as a way of preventing medical malpractice and negligence; as a remedy for market failure; as a way of improving performance and efficiency; and as a way of even achieving national health objectives or wider social goals such as equity and accountability. It is assumed that the key issues in regulation are its design and having proper monitoring and enforcement.  The article reviews the regulations instituted to address issues arising from the use of reproductive technologies. Through such analysis, the article seeks to draw attention to the field of technology assessment and regulation in general as applicable to biomedical technologies, in a context of overall commercialisation of medical and health care.
Right-to-left shunt detection sensitivity with air–saline and air–succinil gelatin transcranial Doppler
Authors: Puledda Francesca , Toscano Massimiliano , Pieroni Alessio , Veneroso Gabriele , Di Piero Vittorio , Vicenzini Edoardo 
Published: January 2016

Background Air–saline transcranial Doppler is nowadays the first-choice examination to identify right-to-left shunt. To increase right-to-left shunt detection in echocardiography, cardiologists also use air–gelatin mixtures, which are more stable, more echogenic, and easier to be prepared. Aim We assessed the sensitivity of air–gelatin compared with air–saline for transcranial Doppler right-to-left shunt detection. Methods Air–saline transcranial Doppler, during unilateral middle cerebral artery monitoring at rest and after Valsalva maneuver, was performed in patients referred to our neurosonology laboratory for right-to-left shunt detection. The same transcranial Doppler protocol was repeated with air–gelatin. To consider transcranial Doppler positive for cardiac right-to-left shunt, at least one embolic signal had to be detected within 20″ from contrast injection. Later signals were interpreted of pulmonary origin. Trans-thoracic echocardiography was repeated with both air–saline and air–gelatin. Results A total of 97 patients were enrolled; 46 had negative transcranial Doppler for cardiac right-to-left shunt with both air–saline and air–gelatin; out of these, four patients with air–saline plus two more patients with air–gelatin presented late, isolated microemboli, slightly more numerous with air–gelatin: these were interpreted as pulmonary shunts and confirmed with trans-thoracic echocardiography. In 28 patients with already early positive air–saline transcranial Doppler at rest, air–gelatin induced a marked right-to-left shunt increase, facilitating its visualization at trans-thoracic echocardiography. In 23 patients in whom air–saline transcranial Doppler was negative at rest and positive for cardiac right-to-left shunt only after Valsalva maneuver, air–gelatin was able to reveal shunt also at rest. Conclusions Air–gelatin increases right-to-left shunt detection sensitivity with transcranial Doppler in particular at rest, even in patients in whom air–saline mixture fails to identify the shunt. The choice of air–gelatin mixture should be considered for multicentric, clinical, and research trials.
Identification of imaging selection patterns in acute ischemic stroke patients and the influence on treatment and clinical trial enrollment decision making
Authors: Luby Marie , Warach Steven J , Albers Gregory W , Baron Jean-Claude , Cognard Christophe , Dávalos Antoni , Donnan Geoffrey A , Fiebach Jochen B , Fiehler Jens , Hacke Werner , Lansberg Maarten G , Liebeskind David S , Mattle Heinrich P , Oppenheim Catherine , Schellinger Peter D , Wardlaw Joanna M , Wintermark Max 
Published: January 2016

Background and Purpose For the STroke Imaging Research (STIR) and VISTA-Imaging Investigators The purpose of this study was to collect precise information on the typical imaging decisions given specific clinical acute stroke scenarios. Stroke centers worldwide were surveyed regarding typical imaging used to work up representative acute stroke patients, make treatment decisions, and willingness to enroll in clinical trials. Methods STroke Imaging Research and Virtual International Stroke Trials Archive-Imaging circulated an online survey of clinical case vignettes through its website, the websites of national professional societies from multiple countries as well as through email distribution lists from STroke Imaging Research and participating societies. Survey responders were asked to select the typical imaging work-up for each clinical vignette presented. Actual images were not presented to the survey responders. Instead, the survey then displayed several types of imaging findings offered by the imaging strategy, and the responders selected the appropriate therapy and whether to enroll into a clinical trial considering time from onset, clinical presentation, and imaging findings. A follow-up survey focusing on 6 h from onset was conducted after the release of the positive endovascular trials. Results We received 548 responses from 35 countries including 282 individual centers; 78% of the centers originating from Australia, Brazil, France, Germany, Spain, United Kingdom, and United States. The specific onset windows presented influenced the type of imaging work-up selected more than the clinical scenario. Magnetic Resonance Imaging usage (27–28%) was substantial, in particular for wake-up stroke. Following the release of the positive trials, selection of perfusion imaging significantly increased for imaging strategy. Conclusions Usage of vascular or perfusion imaging by Computed Tomography or Magnetic Resonance Imaging beyond just parenchymal imaging was the primary work-up (62–87%) across all clinical vignettes and time windows. Perfusion imaging with Computed Tomography or Magnetic Resonance Imaging was associated with increased probability of enrollment into clinical trials for 0–3 h. Following the release of the positive endovascular trials, selection of endovascular only treatment for 6 h increased across all clinical vignettes.
Head position and cerebral blood flow in acute ischemic stroke patients: Protocol for the pilot phase, cluster randomized, Head Position in Acute Ischemic Stroke Trial (HeadPoST pilot)
Authors: Brunser Alejandro M , Muñoz Venturelli Paula , Lavados Pablo M , Gaete Javier , Martins Sheila , Arima Hisatomi , Anderson Craig S , Olavarría Verónica V 
Published: January 2016

Rationale Few proven interventions exist for acute ischemic stroke (AIS), and most are expensive and restricted in applicability. Lying flat ‘head down’ positioning of AIS patients has been shown to increase by as much as 20%, mean cerebral blood flow velocities (CBFV) measured by transcranial Doppler (TCD) but whether this translates into clinical improvement is uncertain. Aim To determine if the lying flat position increases mean CBFV in the affected territory as compared to the sitting up position in AIS patients. Methods and design Head Position in Acute Ischemic Stroke Trial (HeadPoST pilot) is a cluster randomized (clusters being months), assessor-blinded end-point, phase IIb trial, where consecutive adults with anterior circulation AIS within 12 h of symptom onset are positioned to a randomized position for 48 h with TCD performed serially. Study outcomes Primary outcome is mean CBFV on TCD at 1 and 24 h after positioning. Secondary outcomes include: serious adverse events, neurological impairment at seven days, and death and disability at 90 days. Sample size estimates Assuming an increase of 8.3 (SD 11.4) cm/s in average of mean CBFV when tilted from 30° to 0°, 46 clusters are required (92 patients in total) to detect a 20% increase of mean CBFV with 90% power and 5% level of significance. Conclusion HeadPoST pilot is a cluster randomized multicenter clinical trial investigating the effect of head positioning on mean CBFV in anterior circulation AIS.
Microtubule-associated protein 1b is required for shaping the neural tube
Authors: Jayachandran Pradeepa , Olmo Valerie N. , Sanchez Stephanie P. , McFarland Rebecca J. , Vital Eudorah , Werner Jonathan M. , Hong Elim , Sanchez-Alberola Neus , Molodstov Aleksey , Brewster Rachel M. 
Published: January 2016

Abstract

Background
Shaping of the neural tube, the precursor of the brain and spinal cord, involves narrowing and elongation of the neural tissue, concomitantly with other morphogenetic changes that contribue to this process. In zebrafish, medial displacement of neural cells (neural convergence or NC), which drives the infolding and narrowing of the neural ectoderm, is mediated by polarized migration and cell elongation towards the dorsal midline. Failure to undergo proper NC results in severe neural tube defects, yet the molecular underpinnings of this process remain poorly understood.

Results
We investigated here the role of the microtubule (MT) cytoskeleton in mediating NC in zebrafish embryos using the MT destabilizing and hyperstabilizing drugs nocodazole and paclitaxel respectively. We found that MTs undergo major changes in organization and stability during neurulation and are required for the timely completion of NC by promoting cell elongation and polarity. We next examined the role of Microtubule-associated protein 1B (Map1b), previously shown to promote MT dynamicity in axons. map1b is expressed earlier than previously reported, in the developing neural tube and underlying mesoderm. Loss of Map1b function using morpholinos (MOs) or δMap1b (encoding a truncated Map1b protein product) resulted in delayed NC and duplication of the neural tube, a defect associated with impaired NC. We observed a loss of stable MTs in these embryos that is likely to contribute to the NC defect. Lastly, we found that Map1b mediates cell elongation in a cell autonomous manner and polarized protrusive activity, two cell behaviors that underlie NC and are MT-dependent.

Conclusions
Together, these data highlight the importance of MTs in the early morphogenetic movements that shape the neural tube and reveal a novel role for the MT regulator Map1b in mediating cell elongation and polarized cell movement in neural progenitor cells.
Human endothelial and foetal femur-derived stem cell co-cultures modulate osteogenesis and angiogenesis
Authors: Inglis Stefanie , Christensen David , Wilson David I. , Kanczler Janos M. , Oreffo Richard O. C. 
Published: January 2016

Abstract
Background
A dynamic vasculature is a prerequisite for bone formation where the interaction of bone cells and endothelial cells is essential for both the development and the healing process of bone. Enhanced understanding of the specific mediators involved in bone cell and endothelial cell interactions offers new avenues for skeletal regenerative applications. This study has investigated the osteogenic and angiogenic potential of co-cultures of human foetal diaphyseal or epiphyseal cells with human umbilical vein endothelial cells (HUVEC) in the presence and absence of vascular endothelial growth factor (VEGF) supplementation.

Methods
Early osteogenic activities of the co-cultures (±VEGF) were assessed by alkaline phosphatase (ALP) activity. Osteogenic and angiogenic gene expression was measured using quantitative polymerase chain reaction. An ex vivo organotypic embryonic chick (E11) femur culture model was used to determine the osteogenic effects of VEGF as determined using micro-computed tomography (μCT) and Alcian blue/Sirius red histochemistry and immunocytochemistry for expression of CD31.

Results
ALP activity and gene expression of ALP and Type-1 collagen was enhanced in foetal skeletal/HUVECs co-cultures. In foetal diaphyseal/HUVECs co-cultures, VEGF reduced the levels of ALP activity and displayed a negligible effect on von Willebrand factor (vWF) and VEGF gene expression. In contrast, VEGF supplementation was observed to significantly increase FLT-1 and KDR gene expression in co-cultures with modulation of expression enhanced, compared to VEGF skeletal monocultures. In the organotypic chick model, addition of VEGF significantly enhanced bone formation, which coincided with elevated levels of CD31-positive  cells in the mid-diaphyseal region of the femurs.

Conclusion
These studies demonstrate a differential skeletal response of early foetal skeletal cells, when co-cultured with endothelial cells and the potential of co-culture models for bone repair. The differential effect of VEGF supplementation on markers of angiogenesis and osteogenesis in co-cultures and organ cultures, demonstrate the importance of the intricate temporal coordination of osteogenic and angiogenic processes during bone formation and implications therein for effective approaches to bone regenerative therapies.
Youth unemployment and active labor market policies in Europe
Authors: Caliendo Marco , Schmidl Ricarda 
Published: January 2016

AbstractSince the economic crisis in 2008, European youth unemployment rates have been persistently high at around 20% on average. The majority of European countries spends significant resources each year on active labor market programs (ALMP) with the aim of improving the integration prospects of struggling youths. Among the most common programs used are training courses, job search assistance and monitoring, subsidized employment, and public work programs. For policy makers, it is of upmost importance to know which of these programs work and which are able to achieve the intended goals – may it be the integration into the first labor market or further education. Based on a detailed assessment of the particularities of the youth labor market situation, we discuss the pros and cons of different ALMP types. We then provide a comprehensive survey of the recent evidence on the effectiveness of these ALMP for youth in Europe, highlighting factors that seem to promote or impede their effectiveness in practice. Overall, the findings with respect to employment outcomes are only partly promising. While job search assistance (with and without monitoring) results in overwhelmingly positive effects, we find more mixed effects for training and wage subsidies, whereas the effects for public work programs are clearly negative. The evidence on the impact of ALMP on furthering education participation as well as employment quality is scarce, requiring additional research and allowing only limited conclusions so far.JEL codes:J13, J68, J64
PERFORMANCE BASED COUPLED CFD-FEM ANALYSIS OF 3-BAY HIGH INDUSTRIAL HALL UNDER NATURAL FIRE
Authors: Malendowski Michal , Glema Adam , Szymkuc Wojciech 
Published: January 2016

In this paper, the main emphasis is put into showing differences between standard fire design of structural elements and performance based approach, that takes into account analysis of structure under natural fire. The exemplary structure is a 3-bay 65,0x110,0 m in plane and 22,0 m high industrial hall with heavy cranes. Because of the significant volume with respect to fire load, there is a low probability that the fully developed fire can occur, nonetheless regarding technological process, a significant local fire could take place and affect the neighbour structure. The most complex approach used in this work is based on coupled CFD-FEM analysis of influence of local fire onto structure.Fire exposure of structural elements is calculated by the coupling scripts, taking into account real heat exposure of section by using adiabatic surface temperature approach.
PREDICTION OF RESIDUAL STRENGTH OF COMPOSITE COLUMNS USING FEM ANALYSIS
Authors: Kim Sun-Hee , Yom Kyong-Soo , Choi Sung-Mo 
Published: January 2016

Fires in buildings cause not only economic losses but also many casualties. A prolonged fire involves the possibility of the damage to structural members, which calls for the repair or reinforcement of the building. Since it is critical to decide whether structural members need reinforcement, the technique to determine the degree of the damage to structural members caused by a fire should be established. CFT columns are superior to generic steel columns in terms of fire resistance performance thanks to the thermal storage effect of the concrete inside the columns. Studies have suggested how to reinforce the concrete to further improve the structural strength and fire resistance performance of CFT columns. When CFT columns of a building are damaged by a fire, it is required to determine preciously how serious the structural deterioration of the members is. The purpose of this study is to evaluate the residual strength of CFT columns damaged by a fire by evaluating the temperature distribution inside the columns and determining the degree of deterioration in the load capacity of concrete and steel in relation to temperature distribution.
INFLUENCE OF SURROUNDING BOUNDARIES ON FIRE COMPARTMENT TEMPERATURE
Authors: Byström Alexandra , Wickström Ulf 
Published: January 2016

This paper shows and demonstrates how an analysis of the energy and mass balance of a fully developed (ventilation controlled) compartment fire can be used as a basis for simple and accurate predictions of fire temperatures. The model has been applied on compartments of light weight concrete structures. A finite element FE analysis has been used to solve the heat transfer equation. Effects of moisture were considered for material properties of the surrounding structure. The results were validated with experiments. The model then accurately predicted the fire temperatures and among other things it showed the influence of moisture in the surrounding structure on the fire temperature. Parametric temperature curves according to EN 1991-1-2, 2002 were shown to overestimate the fire temperature.