bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional neuroanatomical associations of working memory in early‐onset Alzheimer's disease
Authors: Kobylecki Christopher , Haense Cathleen , Harris Jennifer M. , Stopford Cheryl L. , Segobin Shailendra H. , Jones Matthew , Richardson Anna M.T. , Gerhard Alexander , Anton‐Rodriguez José , Thompson Jennifer C. , Herholz Karl , Snowden Julie S. 
Published: March 2017

ObjectiveTo characterize metabolic correlates of working memory impairment in clinically defined subtypes of early‐onset Alzheimer's disease.BackgroundEstablished models of working memory suggest a key role for frontal lobe function, yet the association in Alzheimer's disease between working memory impairment and visuospatial and language symptoms suggests that temporoparietal neocortical dysfunction may be responsible.MethodsTwenty‐four patients with predominantly early‐onset Alzheimer's disease were clinically classified into groups with predominantly amnestic, multidomain or visual deficits. Patients underwent neuropsychological evaluation focused on the domains of episodic and working memory, T1‐weighted magnetic resonance imaging and brain fluorodeoxyglucose positron emission tomography. Fluorodeoxyglucose positron emission tomography data were analysed by using a region‐of‐interest approach.ResultsPatients with multidomain and visual presentations performed more poorly on tests of working memory compared with amnestic Alzheimer's disease. Working memory performance correlated with glucose metabolism in left‐sided temporoparietal, but not frontal neocortex. Carriers of the apolipoprotein E4 gene showed poorer episodic memory and better working memory performance compared with noncarriers.ConclusionsOur findings support the hypothesis that working memory changes in early‐onset Alzheimer's disease are related to temporoparietal rather than frontal hypometabolism and show dissociation from episodic memory performance. They further support the concept of subtypes of Alzheimer's disease with distinct cognitive profiles due to prominent neocortical dysfunction early in the disease course. Copyright © 2017 John Wiley & Sons, Ltd.
Facts, values, and journalism
Authors: Gilbert Susan 
Published: March 2017

AbstractAt a time of fake news, hacks, leaks, and unverified reports, many people are unsure whom to believe. How can we communicate in ways that make individuals question their assumptions and learn? My colleagues at The Hastings Center and many journalists and scientists are grappling with this question and have, independently, reached the same first step: recognize that facts can't be fully understood without probing their connection to values. “Explaining the basics is important, of course, but we also need to diversify our approach to the coverage of science—particularly as it intersects with the matrix of cultural, religious, social, and political values of our readers,” said an article in Undark, an online magazine of science journalism. An editorial in Nature called for scientists to engage directly with citizens in debates over climate change and genome editing, noting that “the ethical issues can be critically dependent on the science, for example, in understanding where the boundaries between non‐heritable and heritable genome modifications might be.”We're here to help.
Space for the Prisoner's Point of View
Authors: Haupt Laura 
Published: March 2017

AbstractThe lead article in this issue discusses a potentially free metaphorical space—that of decision‐making—within the confines, tangible and intangible, of life in jail or prison. By interviewing prisoner‐participants from six clinical studies, Paul Christopher and colleagues sought to find out how these men and women would answer open‐ended questions about their decision to enroll in the research. What the interviewers heard was that none saw themselves as having been inappropriately pressured to do so. In fact, a significant percentage of the prisoners described being dissuaded from participating in the studies. The authors therefore advise that unfair exploitation poses the more relevant research risk to contemporary prisoners in the United States than does coercion, and they encourage investigations into whether prisoners are unfairly restricted or discouraged from joining clinical studies.Although Keramet Reiter makes no reference to etymology in her commentary responding to the article, her argument suggests that the roots of “coerce”—the Latin for “shut up” or “enclose”—remain relevant. Reiter argues that, under current conditions, the people shut up in prisons in the United States cannot make an unfettered choice to join a clinical trial.
Enrolling in Clinical Research While Incarcerated: What Influences Participants’ Decisions?
Authors: Christopher Paul P. , Garcia‐Sampson Lorena G. , Stein Michael , Johnson Jennifer , Rich Josiah , Lidz Charles 
Published: March 2017

AbstractAs a 2006 Institute of Medicine report highlights, surprisingly little empirical attention has been paid to how prisoners arrive at decisions to participate in modern research. With our study, we aimed to fill this gap by identifying a more comprehensive range of factors as reported by prisoners themselves during semistructured interviews. Our participants described a diverse range of motives, both favoring and opposing their eventual decision to join. Many are well‐recognized considerations among nonincarcerated clinical research participants, including a desire for various forms of personal benefit, altruism, and concern about study risks and inconveniences. However, a number of influences seem unique to prisoners. Participants did not report that they were not coerced into enrolling, and they have even been under pressure not to enroll. However, many sought to enroll in order to obtain access to better health care, raising a concern about whether they were unfairly exploited.
Toward an Ethically Sensitive Implementation of Noninvasive Prenatal Screening in the Global Context
Authors: Mozersky Jessica , Ravitsky Vardit , Rapp Rayna , Michie Marsha , Chandrasekharan Subhashini , Allyse Megan 
Published: March 2017

AbstractNoninvasive prenatal screening using cell‐free DNA, which analyzes placental DNA circulating in maternal blood to provide information about fetal chromosomal disorders early in pregnancy and without risk to the fetus, has been hailed as a potential “paradigm shift” in prenatal genetic screening. Commercial provision of cell‐free DNA screening has contributed to a rapid expansion of the tests included in the screening panels. The tests can include screening for sex chromosome anomalies, rare subchromosomal microdeletions and aneuploidies, and most recently, the entire fetal genome.The benefits of this screening tool are generally framed, by both providers and commercial laboratories, as enhancing reproductive autonomy and choice by providing an earlier, simpler, and more accurate screening while potentially reducing the need for invasive follow‐up testing. The majority of the literature has explored these issues empirically or conceptually from a European or North American vantage point, one that assumes normative priorities such as individual reproductive autonomy and the clinical availability of maternal health care or prenatal screening programs within which cell‐free DNA screening is offered. While its implementation has raised both challenges and opportunities, very little is known about real‐world experiences and the implications of the rapid introduction of cell‐free DNA screening outside of North America and Europe, especially in low‐ and middle‐income countries. To begin addressing this gap in knowledge, we organized a four‐day international workshop to explore the ethical, legal, social, economic, clinical, and practical implications of the global expansion of cell‐free DNA screening. We describe eight key insights that arose from the workshop.
Risk of Stress Fracture Varies by Race/Ethnic Origin in a Cohort Study of 1.3 Million US Army Soldiers
Authors: Bulathsinhala Lakmini , Hughes Julie M , McKinnon Craig J , Kardouni Joseph R , Guerriere Katelyn I , Popp Kristin L , Matheny Ronald W , Bouxsein Mary L 
Published: March 2017

ABSTRACT

Stress fractures (SF) are common and costly injuries in military personnel. Risk for SF has been shown to vary with race/ethnicity. Previous studies report increased SF risk in white and Hispanic Soldiers compared with black Soldiers. However, these studies did not account for the large ethnic diversity in the US military. We aimed to identify differences in SF risk among racial/ethnic groups within the US Army. A retrospective cohort study was conducted using data from the Total Army Injury and Health Outcomes Database from 2001 until 2011. SF diagnoses were identified from ICD-9 codes. We used Cox-proportional hazard models to calculate time to SF by racial/ethnic group after adjusting for age, education, and body mass index. We performed a sex-stratified analysis to determine whether the ethnic variation in SF risk depends on sex. We identified 21,549 SF cases in 1,299,332 Soldiers (more than 5,228,525 person-years of risk), revealing an overall incidence rate of 4.12 per 1000 person-years (7.47 and 2.05 per 1000 person-years in women and men, respectively). Using non-Hispanic blacks as the referent group, non-Hispanic white women had the highest risk of SF, with a 92% higher risk of SF than non-Hispanic black women (1.92 [1.81–2.03]), followed by American Indian/Native Alaskan women (1.72 [1.44–1.79]), Hispanic women (1.65 [1.53–1.79]), and Asian women (1.32 [1.16–1.49]). Similarly, non-Hispanic white men had the highest risk of SF, with a 59% higher risk of SF than non-Hispanic black men (1.59 [1.50–1.68]), followed by Hispanic men (1.19 [1.10–1.29]). When examining the total US Army population, we found substantial differences in the risk of stress fracture among racial/ethnic groups, with non-Hispanic white Soldiers at greatest risk and Hispanic, American Indian/Native Alaskan, and Asian Soldiers at an intermediate risk. Additional studies are needed to determine the factors underlying these race- and ethnic-related differences in stress fracture risk. © 2017 American Society for Bone and Mineral Research.
Progressive iron accumulation across multiple sclerosis phenotypes revealed by sparse classification of deep gray matter
Authors: Elkady Ahmed M. , Cobzas Dana , Sun Hongfu , Blevins Gregg , Wilman Alan H. 
Published: March 2017

PurposeTo create an automated framework for localized analysis of deep gray matter (DGM) iron accumulation and demyelination using sparse classification by combining quantitative susceptibility (QS) and transverse relaxation rate (R2*) maps, for evaluation of DGM in multiple sclerosis (MS) phenotypes relative to healthy controls.Materials and MethodsR2*/QS maps were computed using a 4.7T 10‐echo gradient echo acquisition from 16 clinically isolated syndrome (CIS), 41 relapsing‐remitting (RR), 40 secondary‐progressive (SP), 13 primary‐progressive (PP) MS patients, and 75 controls. Sparse classification for R2*/QS maps of segmented caudate nucleus (CN), putamen (PU), thalamus (TH), and globus pallidus (GP) structures produced localized maps of iron/myelin in MS patients relative to controls. Paired t‐tests, with age as a covariate, were used to test for statistical significance (P ≤ 0.05).ResultsIn addition to DGM structures found significantly different in patients compared to controls using whole region analysis, singular sparse analysis found significant results in RRMS PU R2* (P = 0.03), TH R2* (P = 0.04), CN QS (P = 0.04); in SPMS CN R2* (P = 0.04), GP R2* (P = 0.05); and in PPMS CN R2* (P = 0.04), TH QS (P = 0.04). All sparse regions were found to conform to an iron accumulation pattern of changes in R2*/QS, while none conformed to demyelination. Intersection of sparse R2*/QS regions also resulted in RRMS CN R2* becoming significant, while RRMS R2* TH and PPMS QS TH becoming insignificant. Common iron‐associated volumes in MS patients and their effect size progressively increased with advanced phenotypes.ConclusionA localized technique for identifying sparse regions indicative of iron or myelin in the DGM was developed. Progressive iron accumulation with advanced MS phenotypes was demonstrated, as indicated by iron‐associated sparsity and effect size.Level of Evidence: 1Technical Efficacy: Stage 1J. Magn. Reson. Imaging 2017;46:1464–1473.
B1 mapping for bias‐correction in quantitative T1 imaging of the brain at 3T using standard pulse sequences
Authors: Boudreau Mathieu , Tardif Christine L. , Stikov Nikola , Sled John G. , Lee Wayne , Pike G. Bruce 
Published: March 2017

PurposeB1 mapping is important for many quantitative imaging protocols, particularly those that include whole‐brain T1 mapping using the variable flip angle (VFA) technique. However, B1 mapping sequences are not typically available on many magnetic resonance imaging (MRI) scanners. The aim of this work was to demonstrate that B1 mapping implemented using standard scanner product pulse sequences can produce B1 (and VFA T1) maps comparable in quality and acquisition time to advanced techniques.Materials and MethodsSix healthy subjects were scanned at 3.0T. An interleaved multislice spin‐echo echo planar imaging double‐angle (EPI‐DA) B1 mapping protocol, using a standard product pulse sequence, was compared to two alternative methods (actual flip angle imaging, AFI, and Bloch‐Siegert shift, BS). Single‐slice spin‐echo DA B1 maps were used as a reference for comparison (Ref. DA). VFA flip angles were scaled using each B1 map prior to fitting T1; the nominal flip angle case was also compared.ResultsThe pooled‐subject voxelwise correlation (ρ) for B1 maps (BS/AFI/EPI‐DA) relative to the reference B1 scan (Ref. DA) were ρ = 0.92/0.95/0.98. VFA T1 correlations using these maps were ρ = 0.86/0.88/0.96, much better than without B1 correction (ρ = 0.53). The relative error for each B1 map (BS/AFI/EPI‐DA/Nominal) had 95th percentiles of 5/4/3/13%.ConclusionOur findings show that B1 mapping implemented using product pulse sequences can provide excellent quality B1 (and VFA T1) maps, comparable to other custom techniques. This fast whole‐brain measurement (∼2 min) can serve as an excellent alternative for researchers without access to advanced B1 pulse sequences.Level of Evidence: 1Technical Efficacy: Stage 1J. Magn. Reson. Imaging 2017;46:1673–1682.
A Case of Pituitary Gigantism and Acromegaly in Anatolia (Tasmasor, Erzurum, Turkey)
Authors: Özdemir K. , Erdal Ö. D. , Erdal Y. S. 
Published: March 2017

AbstractIn 2003, a tall skeleton belonging to a young adult individual was recovered from a post‐medieval cemetery situated north‐east of the modern city of Erzurum, Turkey. The sex of the individual was not possible to determine. The predicted stature values range from 182 to 200 cm with the average 188.94 cm. The growth was proportional on almost all bones, except for the cranial and facial bones. The selected metric data were compared with the mean values of the male individuals from the same cemetery for differential diagnosis. The individual exhibits characteristics of both pituitary gigantism and acromegaly due to the tumour formation developed in the intrasellar area. Pathological features such as severe osteoarthritis, enthesis and new bone formation around and on the joint surface of the post‐cranial bones, kyphoscoliosis and ankylosis are in agreement with these diagnoses as well. Copyright © 2017 John Wiley & Sons, Ltd.
Synergistic enhancement of mechanical, crystalline and dielectric properties of polyarylene ether nitrile‐based nanocomposites by unidirectional hot stretching–quenching
Authors: You Yong , Du Xuanyi , Mao Hua , Tang Xiaohe , Wei Renbo , Liu Xiaobo 
Published: March 2017

AbstractCopper tetra‐amine phthalocyanine (NH2‐CuPc) was grafted onto barium titanate (BaTiO3) whose surface was modified by carboxylic polyarylene ether nitrile (CPEN) to afford a nano‐filler (CPEN‐f‐BaTiO3@NH2‐CuPc). Through a solution‐casting method combined with ultrasonic dispersion technology, the obtained CPEN‐f‐BaTiO3@NH2‐CuPc was successfully incorporated into biphenyl polyarylene ether nitrile (BP‐PEN) matrix to prepare nanocomposite films with various mass fractions of CPEN‐f‐BaTiO3@NH2‐CuPc (0, 2.0, 5.0, 10.0 and 20.0 wt%). After that, the nanocomposite films were unidirectionally stretched with various stretching ratios at 280 °C. All the nanocomposite films show excellent mechanical and thermal stability, which is provided by the BP‐PEN matrix. The crystallinity and mechanical, thermal and dielectric properties of the nanocomposite films are efficiently enhanced after the unidirectional hot‐stretching process. The results show that hot‐stretching is a useful method for improving the mechanical and crystallization behaviors as well as the thermal and dielectric properties of the nanocomposite films. © 2017 Society of Chemical Industry
Correspondence between the rigid amorphous fraction and nanoconfinement effects on glass formation
Authors: Lee Jonathan , Mangalara Jayachandra Hari , Simmons David S. 
Published: March 2017

ABSTRACTSemicrystalline polymers' properties are strongly influenced by the presence of a “rigid amorphous fraction” (RAF) of material with enhanced glass transition temperature and suppressed mobility. Here, we review striking similarities between this domain and near‐interface regions of altered dynamics in other nanostructured polymers, including thin films, nanocomposites, layered films, and ionomers. Building on these observations, we present results of molecular simulations of model nanolayered polymers in which one layer is crystalline. The results of these simulations, which bear close similarities to semicrystalline homopolymers while providing a well‐defined equilibrium crystal size, suggest that the RAF shares the same phenomenology and mechanism as dynamic interphases in these other polymeric systems. Specifically, the fraction of rigid amorphous material is driven by the scale of cooperative rearrangements characteristic of dynamics in polymers and other supercooled liquids. These results situate the RAF as a specific instance of a general tendency towards broad dynamic interphases in polymers and other glass‐forming materials. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 907–918
Projectile Impact Ignition and Reaction Violent Mechanism for HMX‐Based Polymer Bonded Explosives at High Temperature
Authors: Dai Xiaogan , Wen Yushi , Wen Miaoping , Huang Fenglei , Li Ming , Deng Chuan 
Published: March 2017

AbstractDetermining the mechanism of transition from projectile‐impact ignition to detonation is a complex and difficult task with strong practical applications. Ignition due to low‐velocity projectile impact cannot be properly explained by the available theories. We attempted to determine the mechanisms of initiation of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX)‐based polymer‐bonded explosives (PBXs) in a range of high temperatures, which have rarely been investigated. Comparing the shock initiation results, we found that the low‐velocity projectile impact response mechanisms for a heated explosive are much more complex. Our results show that the impact ignition threshold velocity of the heated explosive does not always decrease with increasing temperature as commonly expected. A temperature dependent plastic power during impact controls the ignition in the range of 25 °C to 75 °C. At 190 °C and 200 °C, there was a sharp rise of reaction degree induced by β→δ phase transition for high HMX‐content PBX. Conversely, such phase transition effect becomes insignificant for low (<50 %) HMX‐content PBX. Our results show that three competing mechanisms affect the impact safety for a high HMX‐content PBX at high temperature, including plastic power, temperature sensitizing, and phase transition.
Direct Determination of Effective Spectral Emissivity of Hot Burnt Gas using Absolutely Calibrated Radiometric Spectrometer
Authors: Lee Wondong , Han Kiwook , Hahn Jae Won 
Published: March 2017

AbstractMeasurement of the radiative characteristics of a flame is important in the field of combustion diagnostics to better understand combustion processes, fuel performance, and combustion engine efficiency. Flame emissivity is one of the most important parameters for investigating such characteristics. This paper proposes a method to directly measure the effective spectral emissivity of a hot burnt gas in flame. We calibrate the radiometric measurement of a mid‐infrared (IR) emission spectrometer using a directly heated graphite blackbody in a national standards laboratory, and determine the flame temperature by fitting the spectrum detected with the emission spectrometer to the color ratio calculated with HITEMP using the species concentrations predicted by ICT thermodynamic calculation. For proof of concept, we determine the spectral effective emissivity of the flame of an IR countermeasure flare in the spectral range of 2–5 μm. We estimate the uncertainty in the measurement to be 11.48 %.
Building Hydrologic Foundations for Applications of ELOHA: How Long A Record Should You Have?
Authors: Williams J. G. 
Published: March 2017

AbstractsThe Ecological Limits of Hydrologic Alteration framework for making regional assessments of environmental flows requires a ‘hydrologic foundation’ of flow data for current and undeveloped conditions. This raises the question how long a record is needed for an adequate hydrologic foundation? The answer depends on the variance in the flow record and on how much uncertainty is tolerable in metrics developed from the flow data. Copyright © 2017 John Wiley & Sons, Ltd.
Pseudodynamic tests with substructuring of a full‐scale precast box‐modularized structure made of reinforced concrete shear walls
Authors: Xu Guoshan , Wang Zhen , Wu Bin , Bursi Oreste S. , Tan Xiaojing , Yang Qingbo , Wen Long , Jiang Hongbin 
Published: March 2017

SummaryA novel horizontal and vertical wall‐to‐wall and wall‐to‐floor connection methods for precast box‐modularized structure with reinforced concrete shear walls (PBSRCSWs) are proposed in this paper. The entailing behavior of the proposed connections and the seismic performance of one full‐scale six‐story PBSRCSWs were experimentally studied by means of pseudodynamic substructure tests. In order to improve the relevant experimental accuracy, we presented and validated one versatile testing platform Hytest, combined with external displacement feedback control (EDFC; Hytest with EDFC). In greater detail, it was shown from the pseudodynamic substructure test results that the proposed Hytest with EDFC can effectively impose the desired displacements on the specimens rather than on the actuators. Moreover, both the horizontal and vertical wall‐to‐wall connections proposed for the PBSRCSWs exhibited a favorable behavior whilst the PBSRCSWs subjected to earthquake records showed an excellent seismic performance.