bluuebunny/crossref_metadata_2025_split huggingface dataset:
Placebo Response in Fragile X‐associated Tremor/Ataxia Syndrome
Authors: Hill Emily J. , Goetz Christopher G. , Stebbins Glenn T. , Hagerman Randi , Ouyang Bichun , Hall Deborah A. 
Published: February 2020

ABSTRACTBackgroundFragile X‐associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder characterized by intention tremor, cerebellar ataxia, and executive dysfunction in carriers of a CGG repeat expansion premutation (55–200 repeats) in the fragile X mental retardation 1 (FMR1) gene. Given reports of poor insight in FXTAS, we postulated that patients with FXTAS would be less likely to exhibit placebo response.ObjectiveTo analyze placebo response from the first randomized controlled trial in FXTAS that evaluated cognitive and motor outcomes after 1 year of treatment with memantine.MethodsData from the placebo arm of the first randomized controlled trial in FXTAS were analyzed. There were 2 coprimary outcomes. Based on studies in Parkinson's disease, placebo responders were defined as individuals with an improvement of at least 50% in the coprimary outcomes. Improvements of 20% and 30% served as secondary cutoff values based on the suggested magnitude of placebo response in other movement disorders.ResultsA total of 36 participants in the placebo group completed baseline and follow‐up evaluations. The average age was 66 ± 7 years, and 60% were men. Average CGG repeat size was 86 ± 18. A total of 19 participants had stage 3 disease. Only 1 patient showed 50% improvement in both coprimary outcomes. At 30% and 20% improvement, there were 2 and 3 patients showing placebo response in the coprimary outcomes, respectively.ConclusionsPatients with FXTAS exhibited low rates of placebo response in a randomized controlled trial. Further studies on the relationship between baseline insight and placebo responsivity are applicable to FXTAS and other disorders exhibiting cognitive impairment.
Frequency diverse array with random logarithmically increasing frequency offset
Authors: Huang Gaojian , Ding Yuan , Ouyang Shan , Fusco Vincent 
Published: February 2020

AbstractThe frequency diverse arrays (FDAs) have been extensively investigated since it can provide a unique angle‐range‐dependent beampattern. This range‐dependent characteristic can suppress the range ambiguous clutters, leading to many novel potential Radar applications. Two issues, however, exist in conventional FDA (CFDA) beampatterns, that is, range‐angle coupling and range periodicity. Therefore, for a CFDA Radar, target range information cannot be obtained directly from the beampattern peaks and target ambiguity occurs in the range domain. In this work, a new frequency diverse array (FDA) transmitter architecture with random logarithmically increasing frequency offset (log‐RFDA) is presented. It is shown that the proposed strategy provides a nonperiodic thumbtack‐like beampattern, eliminating the ambiguity in range domain, suffered in the CFDA Radar. Furthermore, reduced side lobe and higher detection resolution can be achieved, compared with the previously reported log‐FDA.
Influence of limb position on assessment of nerve mechanical properties by using shear wave ultrasound elastography
Authors: Rugel Chelsea L. , Franz Colin K. , Lee Sabrina S. M. 
Published: February 2020

AbstractIntroductionEvaluation of nerve mechanical properties has the potential to improve assessment of nerve impairment. Shear wave velocity, as measured by using shear wave (SW) ultrasound elastography, is a promising indicator of nerve mechanical properties such as stiffness. However, elucidation of external factors that influence SW velocity, particularly nerve tension, is required for accurate interpretations.MethodsMedian and ulnar nerve SW velocities were measured at proximal and distal locations with limb positions that indirectly altered nerve tension.ResultsShear wave velocity was greater at proximal and distal locations for limb positions that induced greater tension in the median (mean increase proximal 89.3%, distal 64%) and ulnar (mean increase proximal 91.1%, distal 37.4%) nerves.DiscussionDue to the influence of nerve tension when SW ultrasound elastography is used, careful consideration must be given to limb positioning.
Multiscale design of three‐dimensional nonlinear composites using an interface‐enriched generalized finite element method
Authors: Brandyberry David R. , Najafi Ahmad R. , Geubelle Philippe H. 
Published: February 2020

SummaryA computational framework is developed to model and optimize the nonlinear multiscale response of three‐dimensional particulate composites using an interface‐enriched generalized finite element method. The material nonlinearities are associated with interfacial debonding of inclusions from a surrounding matrix which is modeled using C−1 continuous enrichment functions and a cohesive failure model. Analytic material and shape sensitivities of the homogenized constitutive response are derived and used to drive a nonlinear inverse homogenization problem using gradient‐based optimization methods. Spherical and ellipsoidal particulate microstructures are designed to match a component of the homogenized stress‐strain response to a desired constructed macroscopic stress‐strain behavior.
Organizational capacity and entrepreneurial behavior
Authors: Svensson Per G. , Andersson Fredrik O. , Faulk Lewis 
Published: February 2020

AbstractIn this research note, we examine the relationship between organizational capacity and entrepreneurial behavior in a global sample of 165 nonprofit organizations operating in a single, rapidly growing field of nonprofit activity. Our findings show a strong relationship between organizations' entrepreneurial behavior and levels of organizational capacity. We discuss our results relative to the importance of both organizational capacity and entrepreneurial behavior in a rapidly growing nonprofit subsector. The results contribute to the continued development and refinement of theoretical and empirical work on the causal links between organizational capacity and entrepreneurial behavior more generally.
Continued Decline in Obesity and Severe Obesity Prevalence Among New York City Public School Youth in Grades K‐8: 2011‐2017
Authors: Day Sophia E. , D’Agostino Emily M. , Huang Terry T.‐K. , Larkin Michael , Harr Lindsey , Konty Kevin J. 
Published: February 2020

ObjectiveThis study aimed to estimate population‐level prevalence of obesity and severe obesity for New York City youth and examine the most recent trends over time.MethodsAll public school youth in grades kindergarten through eighth (K‐8) (2011‐2012 through 2016‐2017) with valid weight and height measures were included (N = 1,137,782 unique students; 3,720,297 observations). Age‐ and sex‐specific BMI percentiles for obesity and severe obesity were estimated using Centers for Disease Control and Prevention growth charts. Repeated cross‐sectional analyses were conducted using logistic regression, weighting for missing or invalid responses and accounting for clustering by students and schools to examine trends over time and by sociodemographics.ResultsAmong youth in K‐8 (aged 5‐15 years, 48.8% girls), the prevalence of obesity and severe obesity in 2011‐2012 was 21.5% and 6.4%, respectively, compared with 20.2% and 6.0%, respectively, in 2016‐2017. Since 2011‐2012, decreasing trends in obesity and severe obesity (relative declines: 6.0% and 6.3%, respectively,P < 0.001) have been observed. Significant decreases were observed for all subgroups (P < 0.001), although there remained disparities in relative declines over time by race/ethnicity and poverty.ConclusionsDecreasing trends in obesity and severe obesity among all New York City K‐8 public school youth are promising; however, persistent disparities highlight the need to improve intervention design and implementation strategies for groups disproportionately burdened by obesity.
Striatal Dopamine Responses to Feeding are Altered in People with Obesity
Authors: Eisenstein Sarah A. , Black Kevin J. , Samara Amjad , Koller Jonathan M. , Dunn Julia P. , Hershey Tamara , Klein Samuel , Smith Gordon I. 
Published: February 2020

ObjectiveThis study determined whether striatal dopamine (DA) release is affected by food ingestion and whether the DA response to high‐calorie food images is greater in the fasted than in the fed state in people with obesity.MethodsStriatal DA release was evaluated in 10 people with obesity and prediabetes after consuming a meal to satiation and after fasting overnight as well as in response to viewing images of high‐calorie compared with low‐calorie foods after consuming a meal to satiation or fasting overnight by using positron emission tomography with [11C]raclopride injection.ResultsStriatal DA D2/D3 receptor availability was not different during fasted and fed conditions. Viewing images of high‐calorie foods induced striatal DA release relative to viewing images of low‐calorie foods (P < 0.05), but there was no difference in the magnitude of the response between fasting and fed conditions.ConclusionsPeople with obesity and prediabetes do not increase striatal DA release after eating a meal to satiation compared with fasting overnight and fail to inhibit DA release in response to high‐calorie food stimuli after eating a meal to satiation. These data suggest that impaired DA signaling contributes to greater energy intake during meals in this population.
Current controversies in prenatal diagnosis 2: The 59 genes ACMG recommends reporting as secondary findings when sequencing postnatally should be reported when detected on fetal (and parental) sequencing
Authors: Amor David J. , Chitty Lyn S. , Van den Veyver Ignatia B. 
Published: February 2020

AbstractGenome sequencing is increasingly being used to aid genetic diagnosis in fetuses with structural abnormalities detected on ultrasound examination. However, with clinical exome and genome sequencing, there is potential for the recognition and reporting of incidental or secondary findings unrelated to the indication for ordering the sequencing, but of potential medical value for patient care. In the postnatal setting, the American College of Medical Genetics and Genomics (ACMG) has clear guidelines that state that when offering sequencing, secondary findings should be reported in 59 genes for which ACMG consider there is a clinical evidence that pathogenic variants may result in disease that might be prevented or treated, with the option to opt out of receiving this information. However, these guidelines specifically exclude prenatal sequencing. Here, we report the debate on whether or not pathogenic findings in these 59 genes should or should not be reported in the prenatal setting. Although more were in favour of reporting before the debate, there was no significant consensus from the audience. After the debate there was a swing toward not reporting, but a slim majority (55%) remained in favour, indicating that this is an area requiring further research and the development of evidence‐based guidelines applicable to prenatal proband and trio sequencing.
Ultraviolet‐induced chain extension of poly(ethylene terephthalate) based on radical reaction with the aid of trimethylolpropane triacrylate and glycidyl methacrylate during extrusion
Authors: Huang Wei‐Tao , He Guang‐Jian , Tang Wen‐Dong , Cao Xian‐Wu 
Published: February 2020

AbstractIn order to improve the processing properties of poly(ethylene terephthalate) (PET), carbon–carbon double bonds were end‐capped onto the chain end of PET by reacting with glycidyl methacrylate (GMA) and then the product was reacted with trimethylolpropane triacrylate (TMPTA) based on a free radical reaction initiated by ultraviolet light to form long‐chain branching structures. The reaction was demonstrated by intrinsic viscosity measurements, carboxyl content analysis, Fourier transform infrared spectroscopy and size exclusion chromatography. Then the rheological and thermal properties of PET were investigated with various TMPTA and GMA contents. Chain extended PET displayed higher complex viscosity than pristine PET and pronounced shear‐thinning behavior. Moreover, the relaxation time spectrum revealed that the modified PET displayed a longer relaxation time during the relaxation process, which was attributed to the higher degree of entanglements resulting from long‐chain branching. Besides, its crystallization temperature and melt temperature shifted to lower temperatures, and the glass transition temperature shifted to higher temperature, indicating that the thermal properties of the modified PET had also been improved. Thus this method can be used to improve the overall properties of PET. © 2020 Society of Chemical Industry
Controlled and highly effective ring‐opening polymerization of α‐chloro‐ε‐caprolactone using Zn‐ and Al‐based catalysts
Authors: Bolley Anaëlle , Mameri Samir , Dagorne Samuel 
Published: February 2020

AbstractThe present study details the highly effective and controlled ring‐opening polymerization (ROP) of α‐chloro‐ε‐caprolactone (1, αClεCL), a cyclic ester that has been little explored thus far in ROP catalysis, using Zn‐ and Al‐based catalysts [Zn(C6F5)2(toluene)] (4), [N,N′‐bis(3,5‐di‐tert‐butylsalicylidene)1,3‐diaminopropanato]aluminium(III)benzyloxide (5) and [N,N′‐bis(3,5‐di‐tert‐butylsalicylidene)1,3‐diamino‐2,2′‐dimethylpropanato]aluminium(III)benzyloxide] (6). Chain‐length‐controlled PαClεCL material is produced under solution ROP conditions, as deduced from GPC, NMR, MALDI‐TOF, and kinetic data. In contrast, the ROP of 1 is ill‐defined under bulk ROP conditions due to partial thermal degradation of the polymer chain (presumably through C–Cl cleavage), reflecting the limited stability of PαClεCL. The Al Catalysts 5 and 6 are highly active ROP catalysts of αClεCL at room temperature (TOF up to 2,400 hr−1) to afford well‐defined P(αClεCL). In the case of Catalyst 6, carrying out the ROP of αClεCL under immortal conditions (with BnOH as chain transfer agent) is clearly beneficial to ROP activity and control, with no apparent side‐reaction of chloro‐functionalized PCL chains as the ROP proceeds. The controlled character of these ROPs was further exploited for the production of chain‐length‐controlled PLLA‐b‐PαClεCL diblocks through sequential ROP of l‐lactide and αClεCL, affording copolymers with improved thermal and biodegradable properties.
Observations and modelling of ground temperature evolution in the discontinuous permafrost zone in Nadym, north‐west Siberia
Authors: Kukkonen Ilmo T. , Suhonen Elli , Ezhova Ekaterina , Lappalainen Hanna , Gennadinik Victor , Ponomareva Olga , Gravis Andrey , Miles Victoria , Kulmala Markku , Melnikov Vladimir , Drozdov Dmitry 
Published: February 2020

AbstractWe analyze ground temperatures measured daily at depths of 0–10 m in the Nadym region, north‐west Siberia (65°18′N, 72°6′E). Nadym is located within the discontinuous permafrost zone and the forest–tundra transition subzone, thus representing an area threatened by permafrost thawing. Soil comprises a 0.4–1.0‐m‐thick topmost layer of peat with high porosity (~0.9), underlain by layers of mineral soil (sand, clay, loam) with lower porosities of 0.3–0.4. With a numerical heat transfer model, we provide predictions of general permafrost development for the next 300 years. Furthermore, we apply the model with the same time frame, to predict permafrost evolution in two monitoring boreholes (BH) in the Nadym area, BH 1‐09 and 3‐09 with present (2012–2016) temperatures at the top of the permafrost (TTOP) of −2.0 and 0.0 °C, respectively. Applying a mild warming trend (0.02 °C/yr in mean annual air temperature [MAAT], corresponding to the IPCC representative concentration pathway trend RCP 2.6) does not lead to thawing of permafrost during the applied 300 years of simulation time in BH 1‐09, whereas in BH 3‐09 thawing has already begun. Applying a strong warming trend of 0.05 °C/yr in MAAT (corresponding to RCP 8.5) leads to gradual thawing of permafrost in both boreholes.
Re‐examining how Munc13‐1 facilitates opening of syntaxin‐1
Authors: Magdziarek Magdalena , Bolembach Agnieszka A. , Stepien Karolina P. , Quade Bradley , Liu Xiaoxia , Rizo Josep 
Published: February 2020

AbstractMunc13‐1 is crucial for neurotransmitter release and, together with Munc18‐1, orchestrates assembly of the neuronal SNARE complex formed by syntaxin‐1, SNAP‐25, and synaptobrevin. Assembly starts with syntaxin‐1 folded into a self‐inhibited closed conformation that binds to Munc18‐1. Munc13‐1 is believed to catalyze the opening of syntaxin‐1 to facilitate SNARE complex formation. However, different types of Munc13‐1‐syntaxin‐1 interactions have been reported to underlie this activity, and the critical nature of Munc13‐1 for release may arise because of its key role in bridging the vesicle and plasma membranes. To shed light into the mechanism of action of Munc13‐1, we have used NMR spectroscopy, SNARE complex assembly experiments, and liposome fusion assays. We show that point mutations in a linker region of syntaxin‐1 that forms intrinsic part of the closed conformation strongly impair stimulation of SNARE complex assembly and liposome fusion mediated by Munc13‐1 fragments, even though binding of this linker region to Munc13‐1 is barely detectable. Conversely, the syntaxin‐1 SNARE motif clearly binds to Munc13‐1, but a mutation that disrupts this interaction does not affect SNARE complex assembly or liposome fusion. We also show that Munc13‐1 cannot be replaced by an artificial tethering factor to mediate liposome fusion. Overall, these results emphasize how very weak interactions can play fundamental roles in promoting conformational transitions and strongly support a model whereby the critical nature of Munc13‐1 for neurotransmitter release arises not only from its ability to bridge two membranes but also from an active role in opening syntaxin‐1 via interactions with the linker.
The comforts of home: The association between coresidence with parents and young adults' residential mobility and migration in the United States
Authors: Lei Lei , South Scott J. 
Published: February 2020

AbstractThis study uses data from the 2005 through 2015 waves of the Panel Study of Income Dynamics' Transition to Adulthood supplement to examine the association between young adults' living arrangements and their likelihood of moving. Compared with young adults who live with their parents, young adults who live independently are about twice as likely to move within a state, and four times as likely to move between states, over a biennial period. The negative association between parental coresidence and residential movement is stronger for young men than for young women and for Hispanics than for non‐Hispanic Whites. Increases in parental coresidence explain 70% of the decline in young adults' odds of making an intrastate move, and almost one third of the decline in the odds of making an interstate move, between 2005 and 2015.
Adaptive neural network tracking control for uncertain nonlinear systems with input delay and saturation
Authors: Ma Jiali , Xu Shengyuan , Zhuang Guangming , Wei Yunliang , Zhang Zhengqiang 
Published: February 2020

SummaryIn this article, the adaptive tracking control problem is considered for a class of uncertain nonlinear systems with input delay and saturation. To compensate for the effect of the input delay and saturation, a compensation system is designed. Radial basis function neural networks are directly utilized to approximate the unknown nonlinear functions. With the aid of the backstepping method, novel adaptive neural network tracking controllers are developed, which can guarantee all the signals in the closed‐loop system are semiglobally uniformly ultimately bounded, and the system output can track the desired signal with a small tracking error. In the end, a simulation example is given to illustrate the effectiveness of the proposed methods.
Secure data dissemination techniques for IoT applications: Research challenges and opportunities
Authors: Bodkhe Umesh , Tanwar Sudeep 
Published: February 2020

SummaryInternet of Things (IoT) connects different objects in the physical world to the Internet, and various Internet protocols are used to provide communication services to a large number of these embedded devices termed as smart devices. But, these devices are resource‐constrained, low configured, and have very low power storage capacity, which depends on the services offered by the protocols. For the exchange of information to the end‐users, smart devices communicate through an open channel, such as the Internet, which is not secure enough. Moreover, efficient delivery ratio, secure data forwarding are not achieved because of the enormous amount of data produced by these smart devices and the possibility of security threats. So there is a need to devise a secure and reliable data dissemination scheme for the IoT environment. Motivated from the these facts, this paper presents a systematic review and propose a solution taxonomy for secure data dissemination techniques for various smart IoT‐based applications. This paper also includes a comparison of the state‐of‐the‐art data dissemination techniques used for the Internet of Vehicles (IoVs), Internet of Drones (IoDs), and Internet of Battlefield Things (IoBTs) applications along with their merits and demerits. Finally, the research challenges and possible countermeasures are also discussed in detail, which gives insights to the beginners who want to start work in this emerging
area.
A methodology for modeling sociotechnical systems to facilitate exploratory policy analysis
Authors: Pennock Michael J. , Bodner Douglas A. 
Published: February 2020

AbstractAddressing modern societal challenges often requires the consideration of sociotechnical systems. Sociotechnical systems consist of technological, organizational, and social systems interacting to achieve a goal. Developing effective approaches to modeling sociotechnical systems could enable policy makers to better understand the implications of policy options prior to implementation. Through past work, the authors evaluated a modeling methodology intended to accomplish that goal. While the methodology was found to be useful, there were also significant limitations. In this paper, the authors analyze these limitations through the lens of consolidative versus exploratory modeling. The result is a substantial revision of the modeling methodology that moves from a sequential 10‐step process to a multiphase process intended to facilitate exploratory modeling and detect unintended policy consequences.