bluuebunny/crossref_metadata_2025_split huggingface dataset:
Error analysis of helmholtz‐based MR‐electrical properties tomography
Authors: Mandija Stefano , Sbrizzi Alessandro , Katscher Ulrich , Luijten Peter R. , van den Berg Cornelis A.T. 
Published: November 2017

PurposeMR electrical properties tomography (MR‐EPT) aims to measure tissue electrical properties by computing spatial derivatives of measured
data. This computation is very sensitive to spatial fluctuations caused, for example, by noise and Gibbs ringing. In this work, the error arising from the computation of spatial derivatives using finite difference kernels (FD error) has been investigated. In relation to this FD error, it has also been investigated whether mitigation strategies such as Gibbs ringing correction and Gaussian apodization can be beneficial for conductivity reconstructions.MethodsConductivity reconstructions were performed on a phantom (by means of simulations and MR measurements at 3T) and on a human brain model. The accuracy was evaluated as a function of image resolution, FD kernel size, k‐space windowing, and signal‐to‐noise ratio. The impact of mitigation strategies was also investigated.ResultsThe adopted small FD kernel is highly sensitive to spatial fluctuations, whereas the large FD kernel is more noise‐robust. However, large FD kernels lead to extended numerical boundary error propagation, which severely hampers the MR‐EPT reconstruction accuracy for highly spatially convoluted tissue structures such as the human brain. Mitigation strategies slightly improve the accuracy of conductivity reconstructions. For the adopted derivative kernels and the investigated scenario, MR‐EPT conductivity reconstructions show low accuracy: less than 37% of the voxels have a relative error lower than 30%.ConclusionThe numerical error introduced by the computation of spatial derivatives using FD kernels is one of the major causes of limited accuracy in Helmholtz‐based MR‐EPT reconstructions. Magn Reson Med 80:90–100, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Effect of body temperature on the pharmacokinetics of a triarylmethyl‐type paramagnetic contrast agent used in EPR oximetry
Authors: Matsumoto Ken‐ichiro , Hyodo Fuminori , Mitchell James B. , Krishna Murali C. 
Published: November 2017

PurposePharmacokinetics of the tri[8‐carboxy‐2,2,6,6‐tetrakis(2‐hydroxymethyl)benzo[1,2‐d:4,5‐d’]bis(1,3)dithio‐4‐yl]methyl radical (Oxo63) after a single bolus and/or continuous intravenous infusion was investigated in tumor‐bearing C3H mice with or without body temperature control while under anesthesia.MethodThe in vivo time course of Oxo63 in blood was measured using X‐band electron paramagnetic resonance spectroscopy. Distribution of Oxo63 in normal muscle and tumor tissues was obtained using a surface coil resonator and a 700‐MHz electron paramagnetic resonance spectrometer. The whole‐body distribution of Oxo63 was obtained by 300‐MHz continuous‐wave electron paramagnetic resonance imaging. The high‐resolution 300‐MHz time‐domain electron paramagnetic resonance imaging was also carried out to probe the distribution of Oxo63.ResultsUrination of mice was retarded at low body temperature, causing the concentration of Oxo63 in blood to attain high levels. However, the concentration of Oxo63 in tumor tissue was lower with no control of body temperature than active body temperature control. The nonsystemized blood flow in the tumor tissues may pool Oxo63 at lower body temperature.ConclusionsPharmacokinetics of the contrast agent were found to be significantly affected by body temperature of the experimental animal, and can influence the probe distribution and the image patterns. Magn Reson Med 79:1212–1218, 2018. © Published 2017. This article is a U.S. Government work and is in the public domain in the USA
Can Financial Aid Help to Address the Growing Need for STEM Education? The Effects of Need‐Based Grants on the Completion of Science, Technology, Engineering, and Math Courses and Degrees
Authors: Castleman Benjamin L. , Long Bridget Terry , Mabel Zachary 
Published: November 2017

AbstractAlthough workers in science, technology, engineering, and math (STEM) fields earn above‐average wages, the number of college graduates prepared for STEM jobs lags behind employer demand. A key question is how to recruit and retain college students in STEM majors. We offer new evidence on the role of financial aid in supporting STEM attainment. Exploiting a regression discontinuity that allows for causal inference, we find that eligibility for need‐based financial aid increased STEM credit completion by 20 to 35 percent among academically‐ready students in a large, public higher education system. These results appear to be driven by shifting students into STEM‐heavy course loads, suggesting aid availability impacts the academic choices students make after deciding to enroll. We also find suggestive evidence that aid offers increase degree attainment in STEM fields, although we cannot rule out null impacts on STEM degree production.
Isolation and whole genome sequencing of fetal cells from maternal blood towards the ultimate non‐invasive prenatal testing
Authors: Chen Fang , Liu Ping , Gu Ying , Zhu Zhu , Nanisetti Amulya , Lan Zhangzhang , Huang Zhiwei , Liu Jia Sophie , Kang Xiongbin , Deng Yuqing , Luo Liqiong , Jiang Dan , Qiu Yong , Pan Jianchang , Xia Jun , Xiong Ken , Liu Chao , Xie Lin , Shi Qianyu , Li Jing , Zhang Xiuqing , Wang Wei , Drmanac Snezana , Bolund Lars , Jiang Hui , Drmanac Radoje , Xu Xun 
Published: November 2017

AbstractObjectiveThe purpose of this study were to develop a methodology of isolating fetal cells from maternal blood and use deep sequence demonstrating the promise for complete and accurate genetic screening compared to other non‐invasive prenatal testing.MethodsHere in this study, we developed a double negative selection (DNS) procedure to unbiasedly enrich fetal cells. After validated by short tandem repeat (STR), the isolated circulating fetal cells (CFCs) were subjected to deep whole genome sequencing analysis.ResultsOur DNS protocol significantly increasing the purity of the mimic fetal cells from 1 in 1 million nucleated cells in whole blood to 1:8 to 1:30 (12.5%‐3.33%) after 2 steps of enrichment. Isolated single fetal cell obtained a coverage rate (86.8%) and allelic dropout rate (24.90%) comparative to the reported results of human cell line. Several disease‐associated variants were identified in the whole genome sequencing data of isolated CFCs and further confirmed in the sequencing data of unamplified gDNA.ConclusionIn conclusion, the robustness of DNS and STR to collect CFCs from peripheral maternal blood for the first time coupled with deep sequencing technique demonstrates the possibility of comprehensive non‐invasive prenatal testing of genetic disorders using isolated CFCs.
Adsorption of polycyclic aromatic hydrocarbons and inversion barriers of curved conjugated systems inside the molecular cage ExCage6+
Authors: Denis Pablo A. , Iribarne Federico 
Published: November 2017

AbstractWe investigated the hosting of planar and curved π systems by ExCage6+. The M06‐2X/6‐311G* method and including basis set superposition error (BSSE) corrections showed good agreement with the experimental free energy changes in solution. The mean absolute deviation (MAD) with respect to experiment was 1.3 kcal/mol. The M06‐2X/6‐31G* method exhibited a MAD of 2.1 kcal/mol, so it may be useful to investigate large systems. The good agreement between the M06‐2X/6‐311G*+BSSE results and the M06‐2X/6‐31G* ones was due to a fortuitous error cancelation between basis set incompleteness and BSSE. The interaction energies decreased linearly with the number of CC double bonds present in the PAH, but the shape of the PAH is an important factor in determining the binding strength. Finally, we studied how effective is ExCage6+ in reducing the inversion barriers of buckybowls. For corannulene, sumanene and dibenzo[a,g]corannulene they are reduced by 2.0, 2.7, and 2.0 kcal/mol, respectively. Although these values indicate an induced fit catalysis by ExCage6+, they are far from those values calculated inside bilayer graphene. Therefore, much work is necessary to replicate the reduction of inversion barriers observed for graphene.
A universe of stories: Mobilizing narrative practices during transformative change
Authors: Dalpiaz Elena , Di Stefano Giada 
Published: November 2017

Research Summary: Constructing narratives of transformative change is an important but challenging practice through which strategy‐makers attempt to influence acceptance of an ongoing transformation. To understand whether and how strategy‐makers can construct a steady influx of captivating narratives of transformative change, we analyzed how one noted strategy‐maker assisted the successful transformation of his organization over three decades by orchestrating the production of change narratives. Our analysis reveals that the strategy‐maker constructed and reconstructed meanings of change over time using three sets of distinct but interconnected narrative practices. We develop a dynamic model linking the simultaneous mobilization of these practices to strategy‐makers’ ability to harness the persistent tension between novelty and familiarity in a transformative change, and thereby, win endorsement from key audiences.Managerial Summary: How can storytelling be used to influence acceptance of an ongoing organizational transformation? In this article, we try to answer this question by examining how, over three decades, Italian company Alessi documented its transformation from a manufacturer of kitchen steel utensils to a producer of a variety of household objects purchased also for their symbolic value. The leader behind Alessi's transformation, Alberto Alessi, orchestrated such storytelling effort, targeting employees, customers, retailers, and visitors to Alessi exhibitions. Our findings uncover how stories can be used to win audiences’ endorsement of change through narrative practices aimed at: (a) constructing a collective memory of change, (b) depicting change as a novel but coherent departure from the past, and (c) portraying change as a transcendent endeavor.
An identity perspective on coopetition in the craft beer industry
Authors: Mathias Blake D. , Huyghe Annelore , Frid Casey J. , Galloway Tera L. 
Published: November 2017

Research Summary: To further our understanding of how and why organizations engage in coopetition, we explore cooperative and competitive actions in the craft beer industry. Through an inductive field study, including interviews with craft brewery owners, we propose collective identity and collective norms play a critical role in the persistence of coopetition over time. Our process model suggests that (a) an oppositional collective identity, (b) the shared belief that a rising tide lifts all boats, and (c) the shared belief that advice and assistance should be paid forward, can lead to the persistence of coopetition beyond market category emergence.
Managerial Summary: This paper develops a theory of how smaller, craft‐based organizations (i.e., “Davids”) encourage cohesion and cooperation amongst themselves when operating against an incumbent market of mass‐producers (i.e., “Goliaths”). An ideological opposition to existing players can lead to a shared belief that helping organizations like your own benefits everyone—the rising tide lifts all boats mentality. Similarly, when organizations first enter a market and receive help from established members, they can feel compelled to help others who enter the market after—the pay‐it‐forward mentality. Together, these mechanisms offer an explanation as to how and why coopetition might persist in a market category over time.
Secondary school science teachers' arguments for the particulate nature of matter
Authors: Gunnarsson Robert , Hellquist Björn , Strömdahl Helge , Zelic Dusan 
Published: November 2017

AbstractHow do secondary school science teachers justify the model of a particulate nature of matter, and how do the arguments they use relate to historical arguments? To find out, we individually interviewed 11 in‐service secondary school science teachers (certified to teach chemistry and/or physics in secondary school, and with 2 to 30 years of teaching experience) regarding their arguments for the particulate nature of matter and experiments that could demonstrate the existence of particles. The collected data were qualitatively analyzed. Three qualitatively different categories of arguments could be constructed from data: philosophical arguments, indirect experimental arguments, and direct experimental arguments. The indirect experimental arguments which is the largest category could be further divided into qualitatively different subcategories: nonspecific research and experiments, and chemical, physical, and subatomic experiments. Even though several experiments and arguments were suggested by the informants in our study, the arguments regarding the validity of the experiments were quite uncertain and vague. The experiments and arguments were used to corroborate the particulate nature of matter and taken for granted in advance rather than used to justify a model with particles. The outcome was discussed in relation to scientific arguments and experiments and in view of results from previous science education research. Based on our data, teacher education and in‐service teacher training, as well as teacher guides, were suggested to be more elaborate regarding contemporary knowledge, with direct experimental evidence for the particulate nature of matter being presented.
Flexure pitch bearing concept for individual pitch control of wind turbines
Authors: Juettner Michael , Hasse Alexander , Tremmel Stephan 
Published: November 2017

AbstractThe excessive use of individual pitch control (IPC) for fatigue load reduction is accompanied by the uncertainty of potential bearing failures. This problem, which is due to the small swivel angles associated with IPC, arises because of the rolling and sliding contacts that occur with the rolling element bearings that are typically used. The use of a flexure bearing is proposed as a way of bypassing this issue. The flexure bearing enables a certain range of motion to be exclusively provided by elastic deformation. This article presents a novel bearing concept that is based on the hypothesis that such a flexure bearing can handle the unfavorable load conditions associated with IPC better than a rolling element bearing. Methods for the dimensioning of the aforementioned flexure bearing are therefore presented. The loads, particularly the required elastic rotation angle of the flexure bearing, are determined first. A promising design for the flexure bearing itself is then chosen and adapted to meet the specific requirements of IPC. These methods are applied to develop an initial conceptual design of the novel bearing unit for a 3‐bladed wind turbine of about 3.6 MW. The result demonstrates the feasibility of the concept, and a final discussion presents further opportunities of the design that will make this concept satisfy the special requirements of IPC.
Chest X‐ray Prior to Thyroidectomy: Is It Really Needed?
Authors: Mikhael Alexandra , Patell Rushad , Tabet Michael , Bena James , Berber Eren , Nasr Christian 
Published: November 2017

AbstractBackgroundChest X‐ray (CXR) prior to thyroid surgery continues to be routinely obtained at some institutions despite the lack of evidence for its utility. This study aimed to determine the utility of preoperative CXR in patients undergoing thyroidectomy at a single institution.MethodsIn total, 594 thyroidectomy patients were included in the study. Demographics, CXR findings, anesthesia records and pathologic data were assessed. We investigated whether difficult intubation or cancer stage correlated with the presence of CXR abnormalities.ResultsOf the total cohort, 83% had a preoperative CXR and 67% had cancer on surgical pathology. In total, 56% had at least one CXR abnormality, the most frequent being skeletal abnormalities (25%), followed by tracheal deviation (16%). Of 78 patients (15.8%) with tracheal deviation on CXR, only 5% had a difficult intubation. Tracheal deviation was more commonly seen in non‐cancer cases compared to cancer cases (27 vs. 12%, p < 0.001). CXR impacted management in 4%. Among patients with cancer, a higher T‐stage (>2) was associated with higher rate of tracheal deviation compared to T1 (17 vs. 8%, p < 0.001). While patients with non‐metastatic cancer (n = 277) compared to metastatic cancer patients had a higher proportion of any abnormality on CXR (57 vs. 44%, p = 0.045), there was no significant difference for tracheal deviation, skeletal abnormalities or lung nodules. Of patients with nodules on CXR (n = 29), only 14% were found to have metastatic disease.ConclusionThe utility of preoperative CXR in patients undergoing thyroidectomy is very limited. In the climate of value‐based care, routine use of this modality may be redundant and should only be ordered if clinically indicated.
Multi-scale account of the network structure of macaque visual cortex
Authors: Schmidt Maximilian , Bakker Rembrandt , Hilgetag Claus C. , Diesmann Markus , van Albada Sacha J. 
Published: November 2017

Abstract
Cortical network structure has been extensively characterized at the level of local circuits and in terms of long-range connectivity, but seldom in a manner that integrates both of these scales. Furthermore, while the connectivity of cortex is known to be related to its architecture, this knowledge has not been used to derive a comprehensive cortical connectivity map. In this study, we integrate data on cortical architecture and axonal tracing data into a consistent multi-scale framework of the structure of one hemisphere of macaque vision-related cortex. The connectivity model predicts the connection probability between any two neurons based on their types and locations within areas and layers. Our analysis reveals regularities of cortical structure. We confirm that cortical thickness decays with cell density. A gradual reduction in neuron density together with the relative constancy of the volume density of synapses across cortical areas yields denser connectivity in visual areas more remote from sensory inputs and of lower structural differentiation. Further, we find a systematic relation between laminar patterns on source and target sides of cortical projections, extending previous findings from combined anterograde and retrograde tracing experiments. Going beyond the classical schemes, we statistically assign synapses to target neurons based on anatomical reconstructions, which suggests that layer 4 neurons receive substantial feedback input. Our derived connectivity exhibits a community structure that corresponds more closely with known functional groupings than previous connectivity maps and identifies layer-specific directional differences in cortico-cortical pathways. The resulting network can form the basis for studies relating structure to neural dynamics in mammalian cortex at multiple scales.
Combined Short‐Path Distillation and Solvent‐Assisted Crystallization of Beef Fatty Acid Methyl Esters
Authors: Dugan Michael E. R. , Gzyl Katherine E. , Rolland David C. , Vahmani Payam 
Published: November 2017

AbstractSolvent‐assisted crystallization has previously been employed to remove long‐chain saturated fatty acids (≥ 18 carbons) from animal fat to improve its cold temperature biofuel properties. The same technology can be used for removing long‐chain saturated fatty acids (SFA) from animal fats for human consumption, but SFA remaining (i.e., 14:0 and 16:0) are more atherogenic than longer chain SFA. In the present study, an easy and efficient method was developed using short‐path distillation prior to solvent‐assisted crystallization for the more complete removal of SFA from beef tallow, and for the first time reports the distillation and crystallization behavior of polyunsaturated fatty acid biohydrogenation products (PUFA‐BHP). Shorter chain SFA methyl esters (i.e., 14:0 and 16:0) were efficiently removed at 90 °C, 9.3 Pa, with a rotor speed of 70 rpm and either two cycles of distillation at 90 drops/min or three cycles at 110 drops/min. Stearic acid (18:0) was then effectively removed by crystallization at −20 °C using a sample to methanol ratio of 1:10. The remaining fraction enriched with PUFA‐BHP (i.e., rumenic acid, c9,t11‐18:2, and its precursor vaccenic acid, t11‐18:1) have potential use in disease model (i.e., cell culture and animal) studies to help further elucidate their bioactivity and mode of action, and may in the future have functional food or nutraceutical potential.
Ethical Responsibility - An Arendtian Turn
Authors: Gardiner Rita A. 
Published: November 2017

ABSTRACT:This article contends that Hannah Arendt’s writing can add value to current discussions on responsible leadership. Specifically, considering responsibility through an Arendtian lens offers insights that deepen our understanding of the interconnections among leadership, responsibility, and ethical action. Turning to Arendt can, therefore, increase our grasp of the complexities of leading responsibly. She shows how acting responsibly requires not only ethical forethought but also a willingness to judge for ourselves. Her emphasis on judgment enriches discussions on responsible leadership, encouraging us to think more deeply about what it might mean to act responsibly, and how such action connects with ethics. Examples of irresponsible action are explored as they concern individual and collective judgment in particular political and corporate contexts. Thus, it is by engaging with the messy realities of everyday life that an Arendtian turn can help us rethink leadership, ethics, and responsibility in new and productive ways.
Identification of Clostridium difficile Reservoirs in The Patient Environment and Efficacy of Aerial Hydrogen Peroxide Decontamination
Authors: Yui Samuel , Ali Shanom , Muzslay Monika , Jeanes Annette , Wilson A. Peter R. 
Published: November 2017

OBJECTIVETo identify, using a novel enhanced method of recovery, environmental sites where spores of Clostridium difficile persist despite cleaning and hydrogen peroxide aerial decontamination.DESIGNCohort study.SETTINGTertiary referral center teaching hospital.METHODSIn total, 16 sites representing high-frequency contact or difficult-to-clean surfaces in a single-isolation room or bed area in patient bed bays were sampled before and after terminal or hydrogen peroxide disinfection using a sponge swab. In some rooms, individual sites were not present (eg, there were no en-suite rooms in the ICU). Swab contents were homogenized, concentrated by membrane-filtration, and plated onto selective media. Results of C. difficile sampling were used to focus cleaning.RESULTSOver 1 year, 2,529 sites from 146 rooms and 44 bays were sampled. Clostridium difficile was found on 131 of 572 surfaces (22.9%) before terminal cleaning, on 105 of 959 surfaces (10.6%) after terminal cleaning, and on 43 of 967 surfaces (4.4%) after hydrogen peroxide disinfection. Clostridium difficile persisted most frequently on floor corners (97 of 334; 29.0%) after disinfection. Between the first and third quarters, we observed a significant decrease in the number of positive sites (25 of 390 vs 6 of 256). However, no similar change in the number of isolates before terminal cleaning was observed.CONCLUSIONPersistence of C. difficile in the clinical environment was widespread. Although feedback of results did not improve the efficacy of manual disinfection, numbers of C. difficile following hydrogen peroxide gradually declined.Infect Control Hosp Epidemiol 2017;38:1487–1492