bluuebunny/crossref_metadata_2025_split huggingface dataset:
Max‐IDEAL: A max‐flow based approach for IDEAL water/fat separation
Authors: Soliman Abraam S. , Yuan Jing , Vigen Karl K. , White James A. , Peters Terry M. , McKenzie Charles A. 
Published: September 2013

PurposeTo propose a novel approach to water/fat separation using a unique smoothness constraint.Theory and MethodsChemical‐shift based water/fat separation is an established noninvasive imaging tool for the visualization of body fat in various anatomies. Nevertheless, B0 magnetic field inhomogeneities can hamper the water/fat separation process. In this work, B0 variations are mapped using a convex‐relaxed labeling model which produces a coarse estimate of the field map, while considering T2* decay during the labeling process. Fat and water components are subsequently resolved using T2*‐IDEAL. An adaptive spatial filtering (ASF) was introduced to improve the robustness of the estimate. The method was tested on cardiac and abdominal datasets from healthy volunteers and nonalcoholic fatty liver disease (NAFLD) patients.ResultsOut of 168 cardiac and abdominal images, only 1 case has shown water/fat swaps that can hinder the clinical interpretation of the underlying anatomy.ConclusionThis work demonstrates a new water/fat separation approach that prevents the occurrence of water/fat swaps, by means of a unique smoothness constraint. Incorporating T2* effect in the labeling procedure and including the ASF processing enhance the robustness of the proposed approach and permit the procedure to handle abrupt B0 variations within the field of view. Magn Reson Med 72:510–521, 2014. © 2013 Wiley Periodicals, Inc.
Absolute oxygen R1eimaging in vivo with pulse electron paramagnetic resonance
Authors: Epel Boris , Bowman Michael K. , Mailer Colin , Halpern Howard J. 
Published: September 2013

PurposeTissue oxygen (O2) levels are among the most important and most quantifiable stimuli to which cells and tissues respond through inducible signaling pathways. Tumor O2levels are major determinants of the response to cancer therapy. Developing more accurate measurements and images of tissue O2partial pressure (pO2), assumes enormous practical, biological, and medical importance.MethodsWe present a fundamentally new technique to image pO2in tumors and tissues with pulse electron paramagnetic resonance (EPR) imaging enabled by an injected, nontoxic, triaryl methyl (trityl) spin probe whose unpaired electron's slow relaxation rates report the tissue pO2. Heretofore, virtually all in vivo EPR O2imaging measures pO2with the transverse electron spin relaxation rate, R2e, which is susceptible to the self‐relaxation confounding O2sensitivity.ResultsWe found that the trityl electron longitudinal relaxation rate, R1e, is an order of magnitude less sensitive to confounding self‐relaxation. R1eimaging has greater accuracy and brings EPR O2images to an absolute pO2image, within uncertainties.ConclusionR1eimaging more accurately determines oxygenation of cancer and normal tissue in animal models than has been available. It will enable enhanced, rapid, noninvasive O2images for understanding oxygen biology and the relationship of oxygenation patterns to therapy outcome in living animal systems. Magn Reson Med 72:362–368, 2014. © 2013 Wiley Periodicals, Inc.
Uncertainty in MR tracer kinetic parameters and water exchange rates estimated from T1‐weighted dynamic contrast enhanced MRI
Authors: Zhang Jin , Kim Sungheon 
Published: September 2013

PurposeThe aim of this study was to assess the uncertainty in estimation of MR tracer kinetic parameters and water exchange rates in T1‐weighted dynamic contrast enhanced (DCE) MRI.MethodsSimulated DCE‐MRI data were used to assess four kinetic models; general kinetic model with a vascular compartment (GKM2), GKM2 combined with water exchange (SSM2), adiabatic approximation of the tissue homogeneity model (ATH), and ATH combined with water exchange (ATHX).ResultsIn GKM2 and SSM2, increase in transfer constant (Ktrans) led to underestimation of vascular volume fraction (vb), and increase in vb led to overestimation of Ktrans. Such coupling between Ktrans and vb was not observed in ATH and ATHX. The precision of estimated intracellular water lifetime (τi) was substantially improved in both SSM2 and ATHX when Ktrans > 0.3 min−1. Ktrans and vb from ATHX model had significantly smaller errors than those from ATH model (P < 0.05).ConclusionThe results of this study demonstrated the feasibility of measuring τi from DCE‐MRI data albeit low precision. While the inclusion of water exchange improved the accuracy of Ktrans, vb, and the interstitial volume fraction estimation (ve), it lowered the precision of other kinetic model parameters within the conditions investigated in this study. Magn Reson Med 72:534–545, 2014. © 2013 Wiley Periodicals, Inc.
Revised motion estimation algorithm for PROPELLER MRI
Authors: Pipe James G. , Gibbs Wende N. , Li Zhiqiang , Karis John P. , Schar Michael , Zwart Nicholas R. 
Published: September 2013

PurposeTo introduce a new algorithm for estimating data shifts (used for both rotation and translation estimates) for motion‐corrected PROPELLER MRI. The method estimates shifts for all blades jointly, emphasizing blade‐pair correlations that are both strong and more robust to noise.Theory and MethodsThe heads of three volunteers were scanned using a PROPELLER acquisition while they exhibited various amounts of motion. All data were reconstructed twice, using motion estimates from the original and new algorithm. Two radiologists independently and blindly compared 216 image pairs from these scans, ranking the left image as substantially better or worse than, slightly better or worse than, or equivalent to the right image.ResultsIn the aggregate of 432 scores, the new method was judged substantially better than the old method 11 times, and was never judged substantially worse.ConclusionThe new algorithm compared favorably with the old in its ability to estimate bulk motion in a limited study of volunteer motion. A larger study of patients is planned for future work. Magn Reson Med 72:430–437, 2014. © 2013 Wiley Periodicals, Inc.
Reliability‐based design for slopes reinforced with a row of drilled shafts
Authors: Li Lin , Liang Robert Y. 
Published: September 2013

SUMMARYIn this paper, a reliability‐based computational algorithm was developed and coded into a computer program, P‐UASLOPE, for design of a row of equally spaced drilled shafts to stabilize an unstable slope while achieving the required target reliability index with minimum volume of drilled shafts. The Monte Carlo simulation technique was used in the previously developed deterministic computational program, in which the limiting equilibrium method of slices was modified to incorporate the arching effects of the drilled shafts in a slope. Uncertainties of soil parameters in the slope were considered by statistical descriptors, including mean, coefficient of variance, and distribution function. Model errors of the semi‐empirical predictive equation for the load transfer factor for characterizing the soil arching effects were considered by statistics of bias. A total of 41 cases of 3‐D finite element simulation results were used to determine the statistics of bias. Two design examples, one is a two‐layer slope and the other one is an actual failed slope, were given to demonstrate the use of P‐UASLOPE program for optimized design of drilled shafts reinforced slope system to achieve the most economic combination of design variables (i.e., location, spacing, diameter, and length of drilled shafts) to satisfy the design requirements in terms of target reliability index and the structural performance of the drilled shafts. A single value of factor of safety chosen in the deterministic approach may not yield the desired level of reliability as uncertainties of soil parameters and model errors cannot be accounted for systematically. Copyright © 2013 John Wiley & Sons, Ltd.
Communicating “pink”: an analysis of the communication strategies, transparency, and credibility of breast cancer social media sites
Authors: Fussell Sisco Hilary , McCorkindale Tina 
Published: September 2013

In public relations, the social media explosion has significantly impacted how organizations communicate to their various publics through sites such as Facebook and Twitter. Although previous studies have investigated dialogic communication and relationship building strategies in organizations, few have carried out this in terms of an organization's overall social media presence, especially with nonprofits. Research has found most nonprofits are not taking full advantage of social media. Moreover, the organizations that did use social media typically employed one‐way communication strategies focusing primarily on information dissemination.This study quantitatively analyzed the transparency and credibility of breast cancer nonprofits are participating on social media sites, specifically Facebook and Twitter, and how these sites affect perceptions of credibility and transparency. Overall, most top breast cancer nonprofits are active on both Twitter and Facebook but differ in terms of activity, credibility, and transparency. Organizations that tweeted more had more “likes”, more followers, and more overall tweets and were seen to be more transparent and credible by virtue of activity alone. This study also found a strong relationship between the transparency and credibility of the organization. Therefore, organizations need to use social media sites not only to communicate with their audiences but also to engage in dialogue on a regular basis. Copyright © 2013 John Wiley & Sons, Ltd.
Newborn screening program for hemoglobinopathies in Rio de Janeiro, Brazil
Authors: de Castro Lobo Clarisse Lopes , Ballas Samir K. , Domingos Ana Carolina Bonini , Moura Patricia G. , do Nascimento Emilia Matos , Cardoso Gilberto Perez , de Carvalho Silvia Maia Farias 
Published: September 2013

AbstractBackgroundNewborn screening for hemoglobinopathy in Brazil has been decentralized until 2001 when the Health Ministry of Brazil established the National Newborn Hemoglobinopathy Screening Program. The State of Rio de Janeiro started a program in collaboration with the State Health Department and the Institute of Hematology in Rio (HEMORIO). The goal of this study was to evaluate the effectiveness of the first 10 years of the Newborn Hemoglobinopathy Screening Program in identifying and managing infants with Sickle cell disease (SCD) in the State of Rio de Janeiro.ProcedureBlood samples from 1,217,833 neonates were analyzed by High Performance Liquid Chromatography. Infants with SCD were enrolled in comprehensive treatment programs.ResultsData showed that 4.87% of the newborns were heterozygous for a hemoglobin variant, 0.08% were homozygous or doubly heterozygous for abnormal hemoglobins and 95.02% had normal hemoglobin. All the 912 newborns with SCD were referred for treatment at HEMORIO, 34 (3.7%) of these died due to acute chest syndrome, sepsis or splenic sequestration. Four more children died of unknown causes. The implementation of the Rio de Janeiro Newborn Screening Program gradually increased the area of the State covered by the program.ConclusionData collected during the 10 years of the program showed reduction in mortality of patients with SCD in comparison to available historical statistical data before the implementation of the national screening program. This 10‐year study showed that early diagnosis and treatment of newborns was associated with improved survival and quality of life of Brazilian children with SCD. Pediatr Blood Cancer 2014;61:34–39. © 2013 Wiley Periodicals, Inc.
Useful marker of oscillatory lung function in methacholine challenge test—comparison of reactance and resistance with dose–response slope
Authors: Yoon Jung Won , Shin Youn Ho , Jee Hye Mi , Chang Sun Jung , Baek Ji Hyeon , Choi Sun Hee , Kim Hyeong Yun , Han Man Yong 
Published: September 2013

SummaryBackgroundThere are few studies focusing on the comparison of resistance (Rrs) and reactance (Xrs) in impulse oscillometry system (IOS) in the bronchial challenge test using dose–response slope (DRS), a quantitative index of bronchial hyperresponsiveness.Material and MethodsWe conducted a case–control study of 144 asthmatic and 218 non‐asthmatic children to compare the diagnostic accuracy of two‐point linear DRS for FEV1, Rrs5, and Xrs5 (DRS_FEV1, DRS_Rrs5, and DRS_Xrs5) and assessed various diagnostic cut‐off points of provocation concentrations (PC) using receiver operating characteristic (ROC) curves.ResultsDRS_FEV1 had a stronger correlation with DRS_Xrs5 (r = 0.739, P < 0.001) than with DRS_Rrs5 (r = 0.652, P < 0.001) and the area under the ROC curves of DRS_Xrs5 (0.737) was similar to that of DRS_FEV1 (0.732) and higher than that of DRS_Rrs5 (0.668). The area under the ROC curves in order of greater value was as follows: absolute change of Xrs5 (Abs_Xrs5) (0.759) > percent change of FEV1 (Pch_FEV1) (0.735) > Pch_Xrs5 (0.727) > Abs_Rrs5 (0.690) > Pch_Rrs5 (0.630). PC78_Xrs5 and PC0.17_Xrs5 of IOS showed considerably good sensitivity and specificity comparable to those of PC20_FEV1 by spirometry. Additional 18 (13%) children who showed normal spirometric measures were identified as asthmatics with the use of IOS.ConclusionThe utility of the DRS_Xrs5 to differentiate asthmatics from controls was comparable to that of the DRS_FEV1 and better than that of the DRS_Rrs5. In addition, IOS could detect additional asthmatic patients who did not show positive responses in spirometry. Pediatr Pulmonol. 2014; 49:521–528. © 2013 Wiley Periodicals, Inc.
The E2F1/DNMT1 axis is associated with the development of AR negative castration resistant prostate cancer
Authors: Valdez Conrad David , Kunju Lakshmi , Daignault Stephanie , Wojno Kirk J. , Day Mark L. 
Published: September 2013

AbstractBACKGROUNDResearch on castration resistant prostate cancer (CRPC) has focused primarily on functional alterations of the androgen receptor (AR). However, little is known about the loss of AR gene expression itself and the possible contribution of AR negative cells to CRPC.METHODSHuman and murine prostate cancer tissue microarrays (TMAs) were evaluated with antibodies specific for E2F1, DNA methyltransferase 1 or AR. The human prostate cancer TMA consisted of clinical samples ranging from normal tissue to samples of metastatic disease. The murine TMA was comprised of benign, localized or metastatic prostate cancer acquired from TRAMP mice treated with castration and/or 5′‐Aza‐2′‐deoxycytidine (5Aza).RESULTSImmunohistochemical analysis revealed increased nuclear DNMT1 staining in localized PCa (P < 0.0001) and metastatic PCa (P < 0.0001) compared to normal tissue. Examination of specific diagnoses revealed that Gleason seven tumors exhibited greater nuclear DNMT1 staining than Gleason six tumors (P < 0.05) and that metastatic tissue exhibited greater levels of nuclear DNMT1 than Gleason seven tumors (P < 0.01). Evaluation of the murine tissue cores revealed that 8.2% and 8.1% of benign tissue cores stained positive for E2F1 and DNMT1 respectively, while 97.0% were AR positive. Conversely, 81% and 100% of tumors were positive for E2F1and DNMT1 respectively. This was in stark contrast to only 18% of tumors positive for AR. Treatment of mice with 5Aza reduced DNMT1 staining by 30%, while AR increased by 27%.CONCLUSIONSThese findings demonstrate that the E2F1/DNMT1 inhibitory axis of AR transcription is activated during the emergence of CRPC. Prostate 73:1776–1785, 2013. © 2013 Wiley Periodicals, Inc.
Spin textures of strongly correlated spin Hall quantum dots
Authors: Dolcetto Giacomo , Ziani Niccolò Traverso , Biggio Matteo , Cavaliere Fabio , Sassetti Maura 
Published: September 2013

AbstractWe study the spin ordering of a quantum dot defined via magnetic barriers in an interacting quantum spin Hall edge. The spin‐resolved density–density correlation functions are computed. We show that strong electron interactions induce a ground state with a highly correlated spin pattern. The crossover from the liquid‐type correlations at weak interactions to the ground state spin texture found at strong interactions parallels the formation of a one‐dimensional Wigner molecule in an ordinary strongly interacting quantum dot.magnified imageA quantum dot, delimited by two magnetic barriers, embedded into a quantum spin Hall edge.(© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
Best practices in system dynamics modeling
Authors: Martinez‐Moyano Ignacio J. , Richardson George P. 
Published: September 2013

AbstractThis research explores opinions about best practices in system dynamics modeling elicited from a distinguished group of experts in the field. We address three questions: What do practitioners believe is the best way to undertake system dynamics modeling? What specific core activities are essential for exemplary action during the different stages of the modeling process? What do experts believe are the most important practices during the different stages of the modeling process? The researchers used a multi‐method approach involving interviews, virtual meetings using the Internet, statistical analysis of the generated data and, finally, a facilitated face‐to‐face meeting in which experts discussed the results of the study and their implications. The results of this research include 72 best practices grouped into six categories that reflect the stages of the system dynamics modeling process. Copyright © 2013 System Dynamics Society.
“We could think of things that could be science”: Girls' re‐figuring of science in an out‐of‐school‐time club
Authors: Gonsalves Allison , Rahm Jrène , Carvalho Alice 
Published: September 2013

AbstractGrounded in sociocultural theory, this study explores how the figured world of science is reworked through a series of multi‐media activities that were introduced into a girls‐only conversation club in an after school program for Teens. The study is part of a multi‐sited ethnography in which we explored youths' engagement with science within three sites. In this paper, we focus on a qualitative case study of one site. We present an analysis of the kinds of resources and cultural models of science that youth mobilized as they re‐figured science together over time, and in a space usually reserved for talk about girls' issues. Our study revealed that a meaningful introduction of science into an out‐of‐school‐time (OST) space that values youths' prior experiences seemed to depend on a two‐way exchange: re‐figuring their experiences as science‐experiences; and the re‐figuring of science to include their every‐day experiences. The study was successful in helping the girls re‐figure the world of science in ways that went beyond the mobilization of cultural models tied to school science only. Through collage, video production, formal and informal dialogue, youth mobilized resources from youth culture to position themselves as insiders to science and to refigure science to include resources from their everyday experiences. Yet, that figuring was also heavily marked by time and space. Follow‐up interviews point to a limited shifting of what counts as “real science” or how the youth consider themselves in relation to science. We conclude with a discussion of the gap between youth interest driven science experiences and science experiences driven by disciplinary practices detached from the world of youth. We discuss the implications of such a tension for introducing science into OST settings with program goals that extend beyond science learning. © 2013 Wiley Periodicals, Inc. J Res Sci Teach 50: 1068–1097, 2013
Relocation routing for energy balancing in mobile sensor networks
Authors: Deng Yiping , Lin Chuang , Wu Dapeng , Ren Fengyuan 
Published: September 2013

AbstractWireless sensor networks (WSNs) have been widely investigated in the past decades because of its applicability in various extreme environments. As sensors use battery, most works on WSNs focus on energy efficiency issues (e.g., local energy balancing problems) in statically deployed WSNs. Few works have paid attention to the global energy balancing problem for the scenario that mobile sensor nodes can move freely. In this paper, we propose a new routing protocol called global energy balancing routing protocol (GEBRP) based on an active network framework and node relocation in mobile sensor networks. This protocol achieves global energy efficiency by repairing coverage holes and replacing invalid nodes dynamically. Simulation and experiment results demonstrate that the proposed GEBRP achieves superior performance over the existing scheme. In addition, we analyze the delay performance of GEBRP and study how the delay performance is affected by various system parameters.Copyright © 2013 John Wiley & Sons, Ltd.
Fair and efficient Transmission Control Protocol access in the IEEE 802.11 infrastructure basic service set
Authors: Keceli Feyza , Inan Inanc , Ayanoglu Ender 
Published: September 2013

AbstractWhen the stations in an IEEE 802.11 infrastructure basic service set employ Transmission Control Protocol (TCP), this exacerbates per‐flow unfair access problem. We propose a novel analytical model to approximately calculate the maximum per‐flow TCP congestion window limit that prevents packet losses at the access point buffer and therefore provides fair TCP access both in the downlink and uplink. The proposed analysis is unique in considering the effects of varying number of uplink and downlink TCP flows, differing round trip times among TCP connections and the use of delayed TCP acknowledgment (ACK) mechanism. Motivated by the findings of this theoretical analysis and simulations, we design a link layer access control block to be employed only at the access point in order to resolve the unfair access problem. The proposed link layer access control block uses congestion control and ACK filtering approach by prioritizing the access of TCP data packets of downlink flows over TCP ACK packets of uplink flows. Via simulations, we show that the proposed algorithm can provide both short‐term and long‐term fair accesses while improving channel utilization and access delay. Copyright © 2013 John Wiley & Sons, Ltd.
A Layered Zinc(II) Coordination Polymer Containing Infinite Zn–S–Zn Chains and its Cluster‐like Derivative
Authors: Luo Daibing , Chen Ziyi , Wu Liangzhuan , Zhi Jinfang , Lin Zhien 
Published: September 2013

AbstractA layered zinc(II) coordination polymer, Zn(SPh)(im) (1), was synthesized under solvothermal conditions. This compound exhibits a sql topology with zinc thiolate chains cross‐linked by imidazolate ligands. To further incorporate S2– ions into the synthetic system, the animidazole‐ligated P1 cluster, Zn8S(SPh)14(Him)2·PhSSPh (2), was isolated and structurally characterized.
Zirconium Complexes of Two Different Iminopyrrolyl Ligands – Syntheses and Structures
Authors: Kottalanka Ravi K. , Naktode Kishor , Panda Tarun K. 
Published: September 2013

AbstractThe reaction involving N‐aryliminopyrrolyl ligand, 2‐((p‐Me‐C6H3N=CMe)–C4H3NH) (1a) (ImpMe‐H), and Zr(OtBu)4 in a 2:1 molar ratio in toluene at 90 °C afforded the corresponding bis(iminopyrrolyl) complex of zirconium, [(ImpMe)2Zr(OtBu)2] (2a) having two bidentate iminopyrrole groups in the coordination sphere. In contrast, the bulkier 2‐((2,6‐iPr2C6H3N=CH)–C4H3NH) (1b) (ImpDipp‐H) and Zr(OtBu)4 in a 1:1 molar ratio under the same condition yielded the corresponding mono(iminopyrrolyl) complex of zirconium, [(ImpDipp)Zr(OtBu)3(THF)] (2b), which contains only one bidentate iminopyrrole moiety in the coordination sphere. Both complexes were characterized by single‐crystal X‐ray diffraction analysis. The solid‐state structures reveal that the bulky iminopyrrole ligands cause a steric crowding around the zirconium ion along with three tert‐butoxide ligands attached to the central metal atom.