bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fat suppression for ultrashort echo time imaging using a single‐point Dixon method
Authors: Jang Hyungseok , Carl Michael , Ma Yajun , Jerban Saeed , Guo Tan , Zhao Wei , Chang Eric Y. , Du Jiang 
Published: February 2019

PurposeIn ultrashort echo time (UTE) imaging, fat suppression can improve short T2* contrast but can also reduce short T2* signals. The conventional two‐point Dixon (2p‐Dixon) method does not perform well due to short T2* decay. In this study, we propose a new method to suppress fat for high contrast UTE imaging of short T2 tissues, utilizing a single‐point Dixon (1p‐Dixon) method.MethodsThe proposed method utilizes dual‐echo UTE imaging, where UTE is followed by the second TE, chosen flexibly. Fat is estimated by applying a 1p‐Dixon method to the non‐UTE image after correction of phase errors, which is used to suppress fat in the UTE image. In vivo ankle and knee imaging were performed at 3 T to evaluate the proposed method.ResultIt was observed that fat and water signals in tendons were misestimated by the 2p‐Dixon method due to signal decay, while the 1p‐Dixon method showed reliable fat and water separation not affected by the short T2* signal decay. Compared with the conventional chemical shift based fat saturation technique, the 1p‐Dixon based approach showed much stronger signal intensities in the Achilles, quadriceps, and patellar tendons, with significantly improved contrast to noise ratios (CNRs) of 11.8 ± 2.2, 16.0 ± 1.6, and 26.8 ± 1.3 with the 1p‐Dixon method and 0.6 ± 0.2, 4.6 ± 1.0, and 17.5 ± 1.4 with regular fat saturation, respectively.ConclusionThe proposed 1p‐Dixon based fat suppression allows more flexible selection of imaging parameters and more accurate fat and water separation over the conventional 2p‐Dixon in UTE imaging. Moreover, the proposed method provides much improved CNR for short T2 tissues over the conventional fat saturation method.
On error controlled numerical model reduction in FE2‐analysis of transient heat flow
Authors: Ekre Fredrik , Larsson Fredrik , Runesson Kenneth 
Published: February 2019

SummaryNumerical model reduction is exploited for solving the two‐scale problem that arises from the computational homogenization of a model problem of transient heat flow. Since the problem is linear, an orthogonal basis is obtained via the method of spectral decomposition. A key feature is the construction of a symmetrized version of the space‐time variational format, by which it is possible to estimate the error from the model reduction in (i) energy norm and in (ii) a given quantity of interest. In previous work by the authors, this strategy has been applied to the solution of an individual representative volume element problem, whereas the error transport to the macroscale problem in the finite element squared (FE2) approach was ignored. In this paper, such transport of error is included in the error estimate. It is remarkable that it is (still) possible to obtain guaranteed bounds on the error, as compared to the fully resolved discrete finite element problem, while using only the reduced basis and with minor extra computational effort. The performance of the error estimates is demonstrated via numerical results, whereby the subscale is modeled in three dimensions, whereas the macroscale problem is either one or two dimensional.
Critical review of the management of primary central nervous nongerminomatous germ cell tumors
Authors: Abu Arja Mohammad H. , Bouffet Eric , Finlay Jonathan L. , AbdelBaki Mohamed S. 
Published: February 2019

AbstractMultimodal strategies have significantly improved the outcomes for patients with central nervous system nongerminomatous germ cell tumors. Two large cooperative group studies have recently reported much improved outcomes compared with historical series. However, a substantial proportion of patients still attain inadequate responses to initial chemotherapy prior to irradiation, with adverse impact upon survival; optimal induction chemotherapy regimens and radiotherapy strategies are as yet unidentified. Outcomes for patients with relapsed disease remain poor. There is an obvious need to incorporate molecular studies within prospective clinical trials that will likely lead to the incorporation of targeted, more effective future treatment strategies.
Academic socialization, parental educational expectations, and academic self‐efficacy among Latino adolescents
Authors: Cross Fernanda L. , Marchand Aixa D. , Medina Michael , Villafuerte Andrea , Rivas‐Drake Deborah 
Published: February 2019

AbstractThis study examined the direct association between parental educational expectations and adolescents’ academic self‐efficacy, as well as the moderating influence of parental academic socialization messages. Participants were 148 Latino parent–adolescent dyads with the majority of Mexican origin (80.4%). Most of the parent participants were mothers (85.8%). Adolescents were 13 (46%) or 14 (54%) years of age, and 53% identified as female. Adolescents reported their academic self‐efficacy and perceptions of their parents’ educational expectations; parents reported on their academic socialization messages of shame/pressure and effort regarding academics. The results suggest that, after accounting for parents’ level of education and immigrant status, parental educational expectations were positively associated with adolescent academic self‐efficacy. This association was stronger among adolescents whose parents reported transmitting fewer messages of shame/pressure and academic effort. These results point to the importance of nuances in the content and type of academic socialization messages within Latino families.
Young adolescent psychological need profiles: Associations with classroom achievement and well‐being
Authors: Earl Stephen R. , Taylor Ian M. , Meijen Carla , Passfield Louis 
Published: February 2019

AbstractDrawing on self‐determination theory, a person‐centered methodology was adopted to identify distinct pupil profiles based on their psychological need satisfaction. A sample of 586 pupils (387 male, 199 female; mean age = 12.6, range 11–15 years old) from three secondary schools reported their psychological need satisfaction, and well‐ and ill‐being, with teachers rating pupil achievement. Hierarchical cluster analysis revealed five distinct profiles. Four profiles indicated synergy existed between the three needs, showing similar in‐group levels of satisfaction across the needs but in varying amounts. Univariate and multivariate analyses, controlling for school and taught subject, revealed the satisfied group displayed the highest classroom performance (F4,540 = 7.03; p < 0.001; ηp2 = 0.05), well‐being (F8,1,136 = 45.63; p < 0.001; Wilk's Λ = 0.57; ηp2 = 0.24) and lowest ill‐being (F8,1,134 = 23.39; p < 0.001; Wilk's Λ = 0.74, ηp2 = 0.14), whereas the dissatisfied group displayed the most adverse outcomes. The findings illustrate that the three psychological needs may operate interdependently and should be considered in combination rather than in isolation. The research offers practical insights into why pupils may function differently in classrooms and could inform targeted initiatives towards pupils with psychological need satisfaction deficits.
Electron Density of Polymeric Nanoparticles Determined by Image Processing of Transmission Electron Micrographs: Insights into Heavy Metal Staining Processes
Authors: Reifarth Martin , Müller Walter , Shkodra‐Pula Blerina , Görls Helmar , Schubert Ulrich S. , Heintzmann Rainer , Hoeppener Stephanie 
Published: February 2019

AbstractA crucial parameter for the investigation of in particular low electron scattering materials by transmission electron microscopy is their ability to attenuate the electron beam and by this to generate appropriate contrast. Surprisingly little attempts have been devoted to at least qualitatively judge on this property of materials. Here an automated imaging analysis algorithm is introduced for the determination of a characteristic electron attenuation factor for homo‐ and (co)polymer nanoparticles which provides a means to access a measure for the contrast in a systematic study of the inherent contrast as well as of the contrast of the nanoparticles after staining procedures. The determination is based on similar imaging conditions for different nanoparticle systems, which enables a comparative approach. Additionally, based on the importance and versatility of osmium tetroxide staining, experiments are conducted elucidating the staining process of model nanoparticle systems bearing olefinic groups. The binding of osmium tetroxide in the environment of the nanoparticle is investigated by means of high‐resolution electrospray mass spectrometry.
Roles of the ClpX IGF loops in ClpP association, dissociation, and protein degradation
Authors: Amor Alvaro J. , Schmitz Karl R. , Baker Tania A. , Sauer Robert T. 
Published: February 2019

AbstractIGF‐motif loops project from the hexameric ring of ClpX and are required for docking with the self‐compartmentalized ClpP peptidase, which consists of heptameric rings stacked back‐to‐back. Here, we show that ATP or ATPγS support assembly by changing the conformation of the ClpX ring, bringing the IGF loops closer to each other and allowing efficient multivalent contacts with docking clefts on ClpP. In single‐chain ClpX pseudohexamers, deletion of one or two IGF loops modestly slows association with ClpP but strongly accelerates dissociation of ClpXP complexes. We probe how changes in the sequence and length of the IGF loops affect ClpX–ClpP interactions and show that deletion of one or two IGF loops slows ATP‐dependent proteolysis by ClpXP. We also find that ClpXP degradation is less processive when two IGF loops are deleted.
Celastrol attenuates renal injury in diabetic rats via MAPK/NF‐κB pathway
Authors: Zhang Min , Chen Yan , Yang Mei‐ju , Fan Xin‐Rong , Xie Hui , Zhang Ling , Nie Yu‐Song , Yan Miao 
Published: February 2019

The purpose of this study was to investigate the renal protective effect of celastrol on diabetic rats. Furthermore, the mechanism of its action was discussed whether it was related to MAPK/NF‐κB signaling pathway. There were a total of 36 rats. Six rats were randomly chosen as the control group. The remaining 30 rats were given 1% streptozotocin intraperitoneal injection (50 mg/kg) and were randomly divided into five groups: the model control group, the low‐dose celastrol group, the high‐dose celastrol group, the Tripterygium wilfordii polyglycosides group, and the MAPK/NF‐κB inhibitor group. After 4 weeks of continuous administration, 24‐hr urine volume, urinary protein, blood urea nitrogen, and serum creatinine content were observed, and hematoxylin–eosin (HE) staining of the kidney and liver were evaluated. p38MAPK was designated by immunohistochemical method, and NF‐κB p65 in renal tissue was detected by western blotting. Our results showed that celastrol could not only reduce contents of creatinine and urea nitrogen in blood but also reduce excretion of urinary protein in diabetic rats, improve renal pathological injury, and down‐regulate the expression of p38MAPK and NF‐κB p65. In conclusion, celastrol could protect kidney of diabetic rats by regulating the signal pathway of MAPK/NF‐κB, inhibiting inflammation and delaying renal injury.
Semiglobal finite‐time synchronization of complex networks with stochastic disturbance via intermittent control
Authors: Jiang Wenlin , Li Liangliang , Tu Zhengwen , Feng Yuming 
Published: February 2019

SummaryThis paper focuses on the problem of semiglobal finite‐time synchronization of stochastic complex networks via an intermittent control strategy. By establishing a finite‐time criterion condition and a novel finite‐time
‐operator differential inequality, combined with convex techniques, some sufficient conditions are obtained to ensure finite‐time synchronization for stochastic complex networks with time delays. An effective controller is given to guarantee inner finite‐time synchronization, especially for a nondelayed dynamic system. This paper provides a simple controller. Finally, a numerical simulation is given to demonstrate the effectiveness of our results.
The influence of riparian vegetation on water quality in a mixed land use river basin
Authors: Chua Evan M. , Wilson Scott P. , Vink Sue , Flint Nicole 
Published: February 2019

AbstractWorldwide, agricultural activities are associated with environmental impacts including riparian degradation and increased waterway pollution. The Fitzroy Basin of Central Queensland lies within the Brigalow Belt Bioregion, which is currently experiencing the highest rates of tree clearing in Australia driven by grazing activities, and this is likely to increase riparian degradation. Local riparian condition, however, has not been consistently monitored within the Fitzroy Basin, and its relationship with water quality has not been well established. This study assessed riparian condition of waterways in the Fitzroy Basin using two established scoring methods (the Rapid Appraisal of Riparian Condition and the Australian Rivers Assessment System Habitat Assessment) and statistically investigated the relationship between stream water quality and local riparian condition. Twelve sites in six waterways were sampled four times over two years, during ambient (nonflood) conditions. Upstream creeks with poorer riparian condition had elevated dissolved organic carbon (DOC), dissolved manganese, sulfate, and total nitrogen (TN) concentrations. High concentrations of these water quality variables were associated with poor local riparian scores in principal components analysis. Dissolved manganese and sulfate were included in the multiple regression model for riparian scores (r values: 0.83 to 0.86; p < 0.001), and DOC and TN were very significantly negatively correlated with riparian scores (r values: −0.55 to −0.69; p < 0.001). Overall, the results suggest that protecting riparian vegetation in the Fitzroy Basin and restoring degraded riparian zones could aid in improving water quality in waterways within this region.
Aggregation‐Induced Ultraviolet Emission Enhancement and the Electroluminescence Based on New Phenanthrene Derivatives
Authors: Ye Chang‐Qing , Zhou Li‐Wei , Fan Cong‐Bin , Dai Guo‐Liang , Wang Xiao‐Mei , Tao Xu‐Tang , Tang Peng‐Yu , Su Wen‐Ming 
Published: February 2019

AbstractA series of new fused‐heterocycle phenanthrene derivatives, namely 9‐(o‐benzofuryl)phenanthrene (Compd. 1), 9,10‐bis(o‐benzofuryl)phenanthrene (Compd. 2), 9‐(o‐dibenzofuryl)phenanthrene (Compd. 3) and 9‐(o‐benzothienyl)phenanthrene (Compd. 4) were designed and synthesized in an effort to obtain aggregation‐induced emission enhancement (AIEE) of ultraviolet (UV) light. The results have shown that Compd. 1 and 2 possess the AIEE of UV‐blue light while Compd. 3 presents UV‐AIEE characteristic. However, Compd. 4 is AIEE‐inactive due to sulfur's heavy atom effect. Based on the absorption and fluorescence in both solution and aggregation, it was found that there is no direct correlation of the intramolecular change‐transfer (ICT) and AIEE properties. Associated with the single‐crystal analyses, it was confirmed that the twisted molecular configuration leading to rigid stacking arrangement with larger intermolecular distance is not immediately relevent to AIEE intensity. It was the degree of the restricted intramolecular rotation (DRIR) in the aggregation that shows direct proportional to the AIEE intensity, in the order of Compd. 1 (5.4‐fold increase) > Compd. 3 (3.2‐fold increase) > Compd. 2 (2.6‐fold increase). UV electroluminescence (EL) from organic light‐emitting diode (OLED) consisting of Compd. 3 as emitting layer was firstly reported.
Hydrogenation of Cinnamaldehyde to Hydrocinnamyl Alcohol on Pt/Graphite Catalyst
Authors: Chang Susheng , Meng Sugang , Fu Xianliang , Zhang Sujuan , Zheng Xiuzhen , Chen Shifu 
Published: February 2019

AbstractChemoselectivity is a cornerstone of catalysis, permitting the targeted modification of specific functional groups within complex starting materials. Herein, we elucidate key structural and electronic factors in converting cinnamaldehyde to related hydrocinnamyl alcohol over Pt/graphite composites. Pt/graphite composites were prepared by a facile hydrothermal method, and performed excellent catalytic performance and selectivity in cinnamaldehyde conversion. When the ratio of Pt loading reaches 4%, cinnamaldehyde conversion is 97.3%, and the yield of hydrocinnamyl alcohol is 94.6%, with the selectivity high to 97.2%. Besides graphite, other support materials (BN, SiO2, TiO2, Al2O3, activated carbon, graphene and g‐C3N4), are also investigated to probe the reaction mechanism. This work indicates that the chemoselective hydrogenation of cinnamaldehyde over supported Pt catalyst can be flexibly controlled by tuning Pt loading amount and support materials.
Self‐Supporting Electrode of High Conductive PEDOT:PSS/CNTs Coaxial Nanocables Wrapped by MnO2 Nanosheets
Authors: Guan Xunbao , Zhao Liping , Zhang Peng , Song Xuefeng , Liu Jing , Gao Lian 
Published: February 2019

AbstractA free‐standing film of manganese oxide/poly(3,4‐ethylenedioxythiophene):poly (styrene sulfonate)/ carbon nanotubes (MnO2/PEDOT:PSS/CNTs) is obtained and directly applied as self‐supporting electrode of supercapacitors. CNTs (modified by ionic liquid) are homogeneously wrapped by conducting polymer PEDOT:PSS. The presence of PEDOT:PSS prevents ultrathin MnO2 nanosheets from restacking as well as promotes them vertical growth and uniform distribution on the surface of PEDOT:PSS/CNTs. The MnO2/PEDOT:PSS/CNTs hybrid electrode which possesses coaxial nanocable structure exhibits significant improvement both in specific capacitance and conductivity compared with CNTs or MnO2/CNTs electrodes. This specific hybrid structure greatly accelerates electrons transport. The specific capacitance of MnO2/PEDOT:PSS/CNTs electrode is 533 Fcm−3 at the current density of 1 mAcm−2, while the specific capacitance values of CNTs and MnO2/CNTs electrodes at the same current density only show 15 and 150 Fcm−3, respectively. The as‐fabricated MnO2/PEDOT:PSS/CNTs hybrid film also exhibits excellent rate capability and cycle stability. For example, the hybrid film shows a specific capacitance of 265 Fcm−3 at current density of 20 mAcm−2, and the high capacitance retention ratio of 129% is achieved after 20000 cycles. Due to its excellent electrochemical properties and good flexibility, MnO2/PEDOT:PSS/CNTs self‐supporting electrode presents promising applications in flexible supercapacitors.
Fulfilling psychological needs predicts less sleep disruption and worry while awaiting uncertain news
Authors: Howell Jennifer L. , Sweeny Kate 
Published: February 2019

AbstractResearch on self‐determination theory suggests that people have fundamental needs to feel autonomous, competent, and socially connected and that fulfilling these needs is critical for well‐being. In the present study, we examined whether fulfilling psychological needs is associated with physical and psychological well‐being—specifically sleep disruption and worry, two key indicators of well‐being during waiting periods—while managing the unique stress of awaiting uncertain news. In a study of law graduates during the 4 months while they awaited their California bar exam (the exam one is required to pass before practicing law) results, personal increases in need fulfilment related to temporally congruent reductions in sleep disruption and worry. In addition, those whose needs were most fulfilled during the waiting period responded less negatively to failing the bar exam. The picture for need frustration was mixed; only autonomy frustration was associated with concurrent increases in worry, although those whose needs were more frustrated in general also experienced greater worry and sleep disruption on average. On the whole, our findings suggest that self‐determination theory needs may be a fruitful target for interventions that can protect well‐being while people wait and even once their uncertainty is resolved.
Frame flexibility: The role of cognitive and emotional framing in innovation adoption by incumbent firms
Authors: Raffaelli Ryan , Glynn Mary Ann , Tushman Michael 
Published: February 2019

Research SummaryWhy do incumbent firms frequently reject nonincremental innovations? Beyond technical, structural, or economic factors, we propose an additional factor: the degree of the top management team's (TMT) frame flexibility, i.e., their capability to cognitively expand an innovation's categorical boundaries and to cast the innovation as emotionally resonant with the organization's identity, competencies, and competitive boundaries. We argue that inertial forces generally constrict how TMTs perceive innovations, but that frame flexibility can overcome these constraints, increasing the likelihood of adoption and broadening the organization's innovation practices. We advance a theoretical model that relaxes the assumption that cognitive frames are static, showing how they become flexible via categorical positioning, and introduce a role for emotional frames that appeal to organizational members' sentiments and aspirations in innovation adoption.Managerial SummaryConfronting a technological change is one of the most difficult challenges facing any incumbent firm. Technological transitions create pressure for leaders to reframe their mental models while continuing to develop existing capabilities and product category variants. Yet at key junctures in a product class and during technological change, a concrete definition of the firm's innovation boundaries and identity hold a firm hostage to its past. We show how a flexible cognitive frame—coupled with emotional framing—helps leaders and organization members become emotionally engaged in transformation efforts and, in turn, learn about executing nonincremental innovation over time. At technological transitions, perhaps there is no more important role for leaders than to expand their cognitive frames and to infuse these expanded frames with emotion.
Count‐rate, linearity, and performance of new backgammon detector technology
Authors: Melia Hamish A. , Dean Jonathan W. , Smale Lucas F. , Illig Alexis J. , Chantler Christopher T. 
Published: February 2019

The meander wire backgammon technology has high levels of flux and spatial linearity across a wide range of energies. One of the attractive features of these technologies is the stability of response and robustness under long X‐ray exposure, compactness, and portability. A key problem historically has been the limited range of count‐rate for processing to the optimum resolution. We report dramatic advances in this and other areas appropriate for high‐accuracy experiments including tests of quantum electrodynamics, fundamental relativistic atomic physics, X‐ray calibration, and crystallography. We illustrate this technology applied to the Kα1,2 spectra of titanium, chromium, and copper. The quality of the spectra permits deeper insight into atomic and solid state science and permits accurate measurement of energy and relativistic atomic physics processes, below 1‐μm accuracy or down to 1 ppm in energy.