bluuebunny/crossref_metadata_2025_split huggingface dataset:
The development of structural covariance networks during the transition from childhood to adolescence
Authors: Vijayakumar Nandita , Ball Gareth , Seal Marc L. , Mundy Lisa , Whittle Sarah , Silk Tim 
Published: May 2021

AbstractStructural covariance conceptualizes how morphologic properties of brain regions are related to one another (across individuals). It can provide unique information to cortical structure (e.g., thickness) about the development of functionally meaningful networks. The current study investigated how structural covariance networks develop during the transition from childhood to adolescence, a period characterized by marked structural re-organization. Participants (N = 192; scans = 366) completed MRI assessments between 8.5 and 14.5 years of age. A sliding window approach was used to create “age-bins”, and structural covariance networks (based on cortical thickness) were created for each bin. Next, generalized additive models were used to characterize trajectories of age-related changes in network properties. Results revealed nonlinear trajectories with “peaks” in mean correlation and global density that are suggestive of a period of convergence in anatomical properties across the cortex during early adolescence, prior to regional specialization. “Hub” regions in sensorimotor cortices were present by late childhood, but the extent and strength of association cortices as “hubs” increased into mid-adolescence. Moreover, these regional changes were found to be related to rates of thinning across the cortex. In the context of neurocognitive networks, the frontoparietal, default mode, and attention systems exhibited age-related increases in within-network and between-network covariance. These regional and modular developmental patterns are consistent with continued refinement of socioemotional and other complex executive functions that are supported by higher-order cognitive networks during early adolescence.
Association of plasma level of high-mobility group box-1 with necroptosis and sepsis outcomes
Authors: Yoo Hongseok , Im Yunjoo , Ko Ryoung-Eun , Lee Jin Young , Park Junseon , Jeon Kyeongman 
Published: May 2021

AbstractThe role of high-mobility group box-1 (HMGB1) in outcome prediction in sepsis is controversial. Furthermore, its association with necroptosis, a programmed cell necrosis mechanism, is still unclear. The purpose of this study is to identify the association between the plasma levels of HMGB1 and the severity and clinical outcomes of sepsis, and to examine the correlation between HMGB1 and key executors of necroptosis including receptor-interacting kinase 3 (RIPK3) and mixed lineage kinase domain-like- (MLKL) proteins. Plasma HMGB1, RIPK3, and MLKL levels were measured with the enzyme-linked immunosorbent assay from the derivation cohort of 188 prospectively enrolled, critically-ill patients between April 2014 and December 2016, and from the validation cohort of 77 patients with sepsis between January 2017 and January 2019. In the derivation cohort, the plasma HMGB1 levels of the control (n = 46, 24.5%), sepsis (n = 58, 30.9%), and septic shock (n = 84, 44.7%) groups were significantly increased (P < 0.001). A difference in mortality between high (≥ 5.9 ng/mL) and low (< 5.9 ng/mL) HMGB1 levels was observed up to 90 days (Log-rank test, P = 0.009). There were positive linear correlations of plasma HMGB1 with RIPK3 (R2 = 0.61, P < 0.001) and MLKL (R2 = 0.7890, P < 0.001). The difference in mortality and correlation of HMGB1 levels with RIPK3 and MLKL were confirmed in the validation cohort. Plasma levels of HMGB1 were associated with the severity and mortality attributed to sepsis. They were correlated with RIPK3 and MLKL, thus suggesting an association of HMGB1 with necroptosis.
Lithological and stress anisotropy control large-scale seismic velocity variations in tight carbonates
Authors: Trippetta F. , Barchi M. R. , Tinti E. , Volpe G. , Rosset G. , De Paola N. 
Published: May 2021

AbstractOur knowledge of subsurface structures often derives from seismic velocities that are measured during seismic acquisition surveys. These velocities can greatly change due to lithological, fracture frequencies and/or effective pressure/temperature variations. However, the influence of such intrinsic lithological properties and environmental conditions at the large scale is poorly understood due to the lack of comprehensive datasets. Here, we analyze 43 borehole-derived velocity datasets of 3 end-member tight carbonate sequences from Central Italy, including massive pure limestone (Calcare Massiccio, CM), thick-layered (20–50 cm) pure limestone (Maiolica, MA), and thin-layered (2–20 cm) marly limestone (Calcareous Scaglia, CS). Our results show that the main rock parameters and environmental conditions driving large scale velocity variations are bedding and paleostresses, while mineralogical composition and current tectonic stress also play a role. For each of the 3 end-members, measured VP values vary differently with depth, as the thin-layered CS units show a clear increase in Vp, while velocity slightly increases and remains constant for the thick-layered MA and massive CM units, respectively. Such observations show that velocities are affected by specific characteristics of lithological discontinuities, such as the thickness of bedding. Counterintuitively, larger Vp values were recorded in the deformed mountain range than in the undeformed foreland suggesting that higher paleo-stresses increase velocity values by enhancing diagenesis and healing of discontinuities. Our results thus demonstrate that large scale velocity variations are strictly related to variation of lithological properties and to the geological and tectonic history of an area. We suggest that such lithological and environmental controls should be taken into account when developing velocity and mechanical models for tectonically active regions of the Mediterranean Area, where earthquakes mostly nucleate and propagate through carbonate formations, and for resource exploration in fractured carbonate reservoirs.
Management of ongoing direct anticoagulant treatment in patients with hip fracture
Authors: Rostagno Carlo , Cartei Alessandro , Polidori Gianluca , Civinini Roberto , Ceccofiglio Alice , Rubbieri Gaia , Curcio Massimo , Boccaccini Alberto , Peris Adriano , Prisco Domenico 
Published: May 2021

AbstractAim of the present study was to investigate the effects of ongoing treatment with DOACs on time from trauma to surgery and on in-hospital clinical outcomes (blood losses, need for transfusion, mortality) in patients with hip fracture. Moreover we evaluated the adherence to current guidelines regarding the time from last drug intake and surgery. In this observational retrospective study clinical records of patients admitted for hip fracture from January 2016 to January 2019 were reviewed. 74 patients were in treatment with DOACs at hospital admission. Demographic data, comorbidities and functional status before trauma were retrieved. As control group we evaluated 206 patients not on anticoagulants matched for age, gender, type of fracture and ASA score. Time to surgery was significantly longer in patients treated with DOACs (3.6 + 2.7 vs. 2.15 ± 1.07 days, p < 0.0001) and treatment within 48 h was 47% vs. 80% in control group (p < 0.0001). The adherence to guidelines’ suggested time from last drug intake to surgery was 46%. Neither anticipation nor delay in surgery did result in increased mortality, length of stay or complication rates with the exception of larger perioperative blood loss (Hb levels < 8 g/dl) in DOACs patients (34% vs 9% p < 0.0001). Present results suggest that time to surgery is significantly longer in DOAC patients in comparison to controls and adherence to guidelines still limited.
Volatile metal emissions from volcanic degassing and lava–seawater interactions at Kīlauea Volcano, Hawai’i
Authors: Mason Emily , Wieser Penny E. , Liu Emma J. , Edmonds Marie , Ilyinskaya Evgenia , Whitty Rachel C. W. , Mather Tamsin A. , Elias Tamar , Nadeau Patricia Amanda , Wilkes Thomas C. , McGonigle Andrew J. S. , Pering Tom D. , Mims Forrest M. , Kern Christoph , Schneider David J. , Oppenheimer Clive 
Published: May 2021

AbstractVolcanoes represent one of the largest natural sources of metals to the Earth’s surface. Emissions of these metals can have important impacts on the biosphere as pollutants or nutrients. Here we use ground- and drone-based direct measurements to compare the gas and particulate chemistry of the magmatic and lava–seawater interaction (laze) plumes from the 2018 eruption of Kīlauea, Hawai’i. We find that the magmatic plume contains abundant volatile metals and metalloids whereas the laze plume is further enriched in copper and seawater components, like chlorine, with volatile metals also elevated above seawater concentrations. Speciation modelling of magmatic gas mixtures highlights the importance of the S2− ligand in highly volatile metal/metalloid degassing at the magmatic vent. In contrast, volatile metal enrichments in the laze plume can be explained by affinity for chloride complexation during late-stage degassing of distal lavas, which is potentially facilitated by the HCl gas formed as seawater boils.
Rapid metal pollutant deposition from the volcanic plume of Kīlauea, Hawai’i
Authors: Ilyinskaya Evgenia , Mason Emily , Wieser Penny E. , Holland Lacey , Liu Emma J. , Mather Tamsin A. , Edmonds Marie , Whitty Rachel C. W. , Elias Tamar , Nadeau Patricia A. , Schneider David , McQuaid James B. , Allen Sarah E. , Harvey Jason , Oppenheimer Clive , Kern Christoph , Damby David 
Published: May 2021

AbstractLong-lived basaltic volcanic eruptions are a globally important source of environmentally reactive, volatile metal pollutant elements such as selenium, cadmium and lead. The 2018 eruption of Kīlauea, Hawai’i produced exceptionally high discharge of metal pollutants, and was an unprecedented opportunity to track them from vent to deposition. Here we show, through geochemical sampling of the plume that volatile metal pollutants were depleted in the plume up to 100 times faster than refractory species, such as magnesium and iron. We propose that this rapid wet deposition of complexes containing reactive and potentially toxic volatile metal pollutants may disproportionately impact localised areas close to the vent. We infer that the relationship between volatility and solubility is an important control on the atmospheric behaviour of elements. We suggest that assessment of hazards from volcanic emissions should account for heterogeneous plume depletion of metal pollutants.
Faculty of Color in Communication Sciences and Disorders: An Overdue Conversation
Authors: Mishra Avinash , Núñez Giselle , Tyson Cara E. 
Published: May 2021

Purpose
Representation of faculty of color (FoC) in the discipline of communication sciences and disorders is limited. FoC face unique challenges within academic institutions. As FoC, we present an overview of three critical areas that directly affect our academic careers: cultural competency, imposter syndrome, and racial microaggression. Definitions, examples, and potential solutions to improve the experience of FoC are provided.

Conclusions
While this article provides a foundation for further discussion, we call upon institutions of higher learning to act now and to recognize the unique obstacles faced by FoC. By implementing solutions, the current academic climate will reflect inclusivity and support of FoC.
MAC layer performance modelling for IEEE 802.15.7 based on discrete‐time Markov chain
Authors: Bhutani Monica , Lall Brejesh , Dixit Abhishek 
Published: May 2021

AbstractPotential lack of enough wireless frequency spectrum has guided researchers towards visible light communication (VLC), emerging as a sturdy support to Wi‐Fi. Though the IEEE 802.15.7 standard has comprehensive medium access control (MAC) and physical (PHY) layer specifications, the emerging VLC technology still faces MAC challenges. Further, throughput is one of the major concerns for the VLC personal area network (VPAN) as it directly impacts the network speed. We propose a novel Markov chain model with two clear channel assessments, which proves to be a significant milestone in improving the network throughput for a star topology VPAN. This paper extends the already available analytical models for the MAC layer to efficiently plan and predict the VPAN performance. We also extensively evaluate other network metrics, like network collision probability and end‐to‐end epoch, to demonstrate the proposed model's applicability. We verify the model's analytical results with elaborate MATLAB simulations and obtain good estimation, especially for large network sizes.
Temperature distribution characteristics and heat defect judgment method based on temperature gradient of suspended composite insulator in operation
Authors: Li Te , Wang Shaohua , Hu Qin , Liu Li , Zhou Luyao , Deng Yu 
Published: May 2021

AbstractIn order to solve the problem of determining the heating suspended composite insulators in transmission lines, infrared tests for composite insulators newly put into operation and with heat defect were conducted. The insulator surface temperature distribution characteristics were obtained. Furthermore, the characteristic parameters based on temperature gradient were revealed and the judgment method of heating defect was established. The results indicate that considerable proportion of the composite insulators in operation have a temperature difference more than 5 K, thus false judgment could occurred when judging heating defect only by temperature difference. Normal composite insulator temperature curve was composed of high‐frequency and low‐frequency components. The influence of the low‐frequency component on the temperature difference is greater than that of the high‐frequency component. Obvious temperature gradient exists at the heating region boundary. The standard deviation of temperature gradient and the maximum absolute value of temperature low‐frequency component gradient are effective characteristic parameters to distinguish whether heating defects exist. The heating defect judgment method was established based on the characteristic parameters, and was verified by field data with an accuracy rate of 94.31%. The method satisfied the heating defect judgement under UAV infrared lens with spatial resolution value not larger than 0.895 mrad.
Disturbance attenuation control for LVRT capability enhancement of doubly fed wind generators
Authors: Qin Boyu , Zhang Ruowei , Li Hengyi , Ding Tao , Liu Wansong 
Published: May 2021

AbstractLow voltage ride through (LVRT) requires wind generation systems (WGS) to maintain continuous operation and provide reactive power support under grid voltage dips. This paper proposes a novel disturbance attenuation control (DAC) approach based on state‐dependent Riccati equation (SDRE) technique to enhance the LVRT capability of doubly fed induction generator‐based (DFIG‐based) WGS. The DAC problems are formulated with the control objectives for rotor side converter and grid side converter, and the weighing matrices are designed with fully studied principles to balance the control effect and cost. The SDRE technique is adopted to solve the DAC problems, and an alternative feasible state dependent coefficient construction algorithm is applied to improve computational efficiency. An active Crowbar circuit with overcurrent limiting mechanism is applied to ensure the rotor current and DC link voltage within the secure zone. Comparisons with conventional PI controller, exact linearization controller and coordinated control strategy are performed, the results demonstrate the proposed DAC approach has a better transient performance and enhances the LVRT capability of DFIG‐based WGS.
Modelling, analysis, and implementation of a switched‐inductor based DC/DC converter with reduced switch current stress
Authors: Sadaf Shima , Al‐Emadi Nasser , Iqbal Atif , Bhaskar Mahajan Sagar , Meraj Mohammad 
Published: May 2021

AbstractThis paper proposes a technique for switch current stress reduction in a Switched Inductor DC‐DC Boost Converter (SIBC). The proposed technique comes up with a low‐cost design, high voltage conversion ratio with a less duty cycle value, and lower current stress without increasing the component count. This topology is basically a transformer‐less design where one diode of the traditional switched inductor configuration has been replaced with a switch, which is in parallel with the existing switch, resulting in a design that can incorporate active switches with a low current rating, since the total input current is equally shared by them. The detailed modes of operation in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM) and steady‐state analysis, the non‐idealities’ effect on voltage gain, design approach, and a comparative study with other DC‐DC converters for some significant performance characteristics are provided. The experimental validations for the performance and working of the 500 W designed prototype are presented.
Advances in quantum secure direct communication
Authors: Zawadzki Piotr 
Published: May 2021

AbstractThe practical implementation of quantum secure direct communication (QSDC) will undoubtedly be a milestone in the development of quantum cryptography. Research is in its final phase and focuses on developing secure protocols that consider realistic constraints and are feasible within the current state of technology. Three well‐known protocols ae compared, Ping‐Pong, Two‐Step and Deng‐Long, in the context of the level of security offered and the challenges related to their implementation. This work explains how the evolution of QSDC protocols from a purely quantum formulation to hybrid classical‐quantum solutions based on the Wyner wiretap channel model can solve most problems encountered. The work aims to inform scientists in other fields of quantum information processing about the latest advances in QSDC. The attached appendix introduces basic concepts for readers unfamiliar with this research area.
An integrated control algorithm of power distribution for islanded microgrid based on improved virtual synchronous generator
Authors: Zhang Liang , Zheng Hao , Wan Tao , Shi Donghan , Lyu Ling , Cai Guowei 
Published: May 2021

AbstractVirtual synchronous generator technology can effectively improve the anti‐interference characteristics of the system frequency and bus voltage in the microgrid, and solve the problems of insufficient damping and low inertia of the system. However, in an islanded microgrid with multiple distributed generation, the difference in line impedance will cause local voltage deviations, which in turn leads to a series of problems, such as reducing power distribution accuracy and increasing bus voltage drop. Therefore, for the island‐type microgrid multi‐inverter distributed power generation parallel system, in order to solve the problem of low power distribution accuracy and large frequency oscillation caused by system parameters in virtual synchronous generator control, an improved virtual synchronous generator control algorithm based on adaptive droop coefficient is proposed in this paper, which not only eliminates the resistance component of the line impedance, makes the system impedance characteristic present a purely inductive nature, but also realises real‐time adjustment of active and reactive power. While maintaining the stability of the bus voltage and system frequency, it maintains high power distribution accuracy and improves the dynamic performance and operational stability of the power grid system.
Study on feature processing schemes for deep‐learning‐based human activity classification using frequency‐modulated continuous‐wave radar
Authors: Hernangómez Rodrigo , Santra Avik , Stańczak Sławomir 
Published: May 2021

AbstractRadar is an attractive sensor for classifying human activity because of its invariance to the environment and its ability to operate under low lighting conditions and through obstacles. Classification for human activity finds applications in human–computer interfaces, user‐intent understanding and contextual‐aware smart homes. Moreover, frequency‐modulated continuous‐wave technology enables radar systems to retrieve both micro‐Doppler and range profiles from humans, which can then be used to recognize target movements. Several feature processing schemes are studied on signatures obtained from a compact, short‐range, 60‐GHz, frequency‐modulated continuous‐wave radar for various human activities. The contribution of distinct features to the performance of classification is analysed and novel convolutional‐ and recurrent‐neural‐network architectures are consequently presented that efficiently combine range and Doppler information for classifying human activity. In particular, applying multibranch deep learning techniques to high‐resolution range profiles and Doppler spectrograms achieves performance similar to that using range‐Doppler map videos although it requires less computational and memory resources.
SADOE: Sequential‐based angle‐Doppler off‐grid estimation with coprime sampling structures for space‐time adaptive processing
Authors: Li Bin , Lu Lei , Zhou Chengwei 
Published: May 2021

AbstractParameter estimation for space‐time adaptive processing (STAP) usually encounters conflicts between estimation accuracy and algorithmic computation complexity in practical applications. In addition, due to the complication of mobile characteristics in STAP, it is often necessary to detect many prominent surface targets. Herein, we propose a sequential approach based on coprime sampling structures for off‐grid angle‐Doppler estimation in the framework of STAP, where both the accuracy and efficiency are well balanced. The estimation is accomplished via three sequential stages, where the initialized relative spatial–temporal map and closed‐form solutions to spatial and temporal parameters based on the rotational invariant technique are subsequently formulated, eventually paired by a Euclidean distance minimization‐based principle. Benefiting from such sequential implementation, the computational complexity can be greatly reduced, and the basis mismatch problem can be avoided in the meantime. Besides, coprime sampling structures enable expanded degrees of freedom in the case of fixed physical cost, adapting to more complicated actual scenarios. Simulation results demonstrate the effectiveness of the proposed algorithm from the aspects of both accuracy and efficiency along with the advance of DOFs.
Influence of thermally induced self‐assembly shish‐kebab crystal on charge transport behaviour in polypropylene/elastomer blends
Authors: Li Jing , Gao Yu , Song Zheng , Peng Jinjing , Xu Xuri 
Published: May 2021

AbstractThis paper reports on the influence of thermally induced self‐assembly shish‐kebab crystal on charge transport behaviour in polypropylene (PP) and PP/propylene‐based elastomer (PBE) blends. The film samples with the shish‐kebab crystal were prepared by adding a β nucleating agent TMB‐5 under thermally induced self‐assembly. Polarised optical microscope （POM）, X‐ray diffraction (XRD) and differential scanning calorimetry (DSC) measurements were performed to understand the crystallisation characteristics of samples. Carrier trap distribution was analysed by isothermal surface potential decay (ISPD) method, and DC breakdown strength measured as well. The decrease of shish‐kebab crystal size, the reduction of trap level, the increase of shallow trap density and the decrease of deep trap density were obtained with the TMB‐5 content. The hopping distance of charges decreased with the shallow trap density increasing. The DC breakdown strength for PP/PBE/TMB‐5 was higher than that for PP/TMB‐5. It is suggested that deep traps are formed on the clear shish‐kebab crystal boundaries, while shallow traps are induced by the elastomer and the un‐crystallisation nucleating agents. Both the carrier trap formation on the crystal boundary and the physical channel orientation of the shish‐kebab crystals affect the charge transport behaviour.