bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphological transition of nanostructures of self‐assembled block copolymers by stimuli‐induced conformational changes in the hydrophilic block
Authors: Jeong Moon Gon , Kim Jiwon , Kwon Jun Ho , Kim Kyoung Taek 
Published: February 2020

AbstractThe morphological control of nanostructures created by the self‐assembly of macromolecular building blocks in solution has practical importance because the structural parameters of nanostructures greatly affect their physical and chemical behavior in solution, for example, pharmacokinetics. Herein, we report that the stimuli‐induced changes to the conformation of the hydrophilic polymer block of a block copolymer (BCP), in this case branched‐linear poly(ethylene glycol)‐b‐poly(styrene) BCPs, are translated to changes in the morphology of the BCP self‐assemblies in solution. Specifically, the cone angle between the poly(ethylene glycol) arms in the tri‐arm hydrophilic block equipped with pyridyl units in the scaffold can be changed by varying the self‐assembly conditions, thus affecting the packing parameter (p) of the BCP. Upon increasing the cone angle by protonating the pyridyl units, the self‐assembled BCP structures underwent changes consistent with a reduction in the p value. In contrast, the chelation of zinc metal cations (Zn2+) to the pyridyl groups resulted in the conformation of the hydrophilic block taking on a closed form, resulting in an apparent increase in the p value of the BCP. Our results could be applied to stimuli‐dependent morphological transitions of other self‐assembled BCP nanostructures in solution.
Experiment study on etching process of graphite electrode by DC hydrogen plasma
Authors: Long Lin , Zhou Weixing , Tang Jingfeng , Zhou Desheng 
Published: February 2020

AbstractDC (direct current) graphite electrodes were used to investigate the hydrogen plasma etching characteristics. Results show that the intermittent spark is marked by physical etching, whereas glow discharge is marked by chemical etching. CH4 is the main gas product, together with the existence of C2H6, C2H4, C3H8, and C3H6. A detailed analysis of the 20‐mA glow discharge showed that the chemical reactions due to the plasma occur mainly through hydrogenation reactions on graphite defects, and different plasma action zones on the graphite also play different roles. Additionally, plasma gaseous reaction processes were analyzed through free radical reactions.
Effects of amendments and microtopography on created tidal freshwater wetland soil morphology and carbon
Authors: Ott Emily T. , Galbraith John M. , Daniels W. Lee , Aust W. Michael 
Published: February 2020

AbstractCreated wetlands used to mitigate impacts to natural wetlands often have lower organic matter, less microtopography, fewer hydric soil field indicators (HSFIs), and higher bulk density (BD) than natural wetlands. Organic matter amendments may improve soil properties soon after wetland construction, but long‐term effects are seldom studied. This study investigated changes with time in soil properties of a sandy freshwater tidal created wetland in the Coastal Plain of Virginia. During construction in 2003/2004, five compost and topsoil treatments were applied, along with pit–mound microtopography. Soil descriptions were made in 2005, 2007, and 2015; samples were taken in 2006 and 2015. Four years after wetland construction, 69% of sandy plots met one or more HSFIs (S5, S6), and 62% of loamy plots met an HSFI (F3). Plots with loamy topsoil additions exhibited greater horizon and structure development, HSFI stability, greater soil mass C (0–30 cm), and higher soil C accumulation. Average soil C accumulation to 30 cm was 2.86 Mg ha−1 yr−1 in topsoil plots. With time, soils became darker (lower value, chroma) and higher in A horizon total C, and grayer (lower chroma) in C horizons, regardless of treatment. In 2015, microtopographic pits had lower color value (2.4), chroma (1.9), BD (0.87 g cm−3), and higher total C (2.39%) than mounds. We recommend adding pit and mound microtopography to created wetlands for increasing diversity of habitat. Further study is needed to see if topsoil and compost amendments improve long‐term plant community development in sandy created wetlands and in other wetland types.
Get rich or die trying… finding revenue model fit using machine learning and multiple cases
Authors: Tidhar Ron , Eisenhardt Kathleen M. 
Published: February 2020

AbstractResearch SummaryWhile revenue models are strategically important, research is incomplete. Thus, we ask: “What is the optimal choice of revenue model?” Using a novel theory‐building method combining machine learning and multi‐case theory building, we unpack optimal revenue model choice for a wide range of products on the App Store. Our primary theoretical contribution is a framework of high‐performing revenue model‐activity system configurations. Our core insight is the fit between value capture (revenue models) and value creation (activities) at the heart of successful business models. Contrastingly, low‐performing products avoid complex value capture (i.e., freemium) and misunderstand value creation (e.g., overweight effort). Overall, we contribute a theoretically accurate and empirically grounded view of successful business models using a pioneering method for theory building using large, quantitative data sets.Managerial SummaryRevenue models are critical for product performance. Yet, the high‐performing choice is often unclear. We combine machine learning with multiple‐case deep‐dives to unpack optimal revenue model choice for a wide range of products on the App Store, a significant setting in the digital economy. Our primary insight is that high‐performing products fit value capture (revenue models) and value creation (activity systems) to form coherent business models. Contrastingly, low‐performing products avoid complex value capture (i.e., freemium) and misunderstand value creation (e.g., overweight effort and price). We also identify the importance of user resources, marketing, offline brand, and product complexity for specific revenue models. Overall, we contribute a framework for the optimal choice of revenue model and spotlight the revenue model‐activity system configurations of successful business models.
Shaping Metallic Nanolattices: Design by Microcontact Printing from Wrinkled Stamps
Authors: Wang Xuepu , Sperling Marcel , Reifarth Martin , Böker Alexander 
Published: February 2020

AbstractA method for the fabrication of well‐defined metallic nanostructures is presented here in a simple and straightforward fashion. As an alternative to lithographic techniques, this routine employs microcontact printing utilizing wrinkled stamps, which are prepared from polydimethylsiloxane (PDMS), and includes the formation of hydrophobic stripe patterns on a substrate via the transfer of oligomeric PDMS. Subsequent backfilling of the interspaces between these stripes with a hydroxyl‐functional poly(2‐vinyl pyridine) then provides the basic pattern for the deposition of citrate‐stabilized gold nanoparticles promoted by electrostatic interaction. The resulting metallic nanostripes can be further customized by peeling off particles in a second microcontact printing step, which employs poly(ethylene imine) surface‐decorated wrinkled stamps, to form nanolattices. Due to the independent adjustability of the period dimensions of the wrinkled stamps and stamp orientation with respect to the substrate, particle arrays on the (sub)micro‐scale with various kinds of geometries are accessible in a straightforward fashion. This work provides an alternative, cost‐effective, and scalable surface‐patterning technique to fabricate nanolattice structures applicable to multiple types of functional nanoparticles. Being a top‐down method, this process could be readily implemented into, e.g., the fabrication of optical and sensing devices on a large scale.
Nano‐Architectured Composite Anode Enabling Long‐Term Cycling Stability for High‐Capacity Lithium‐Ion Batteries
Authors: Kumar Praveen , Berhaut Christopher L. , Zapata Dominguez Diana , De Vito Eric , Tardif Samuel , Pouget Stéphanie , Lyonnard Sandrine , Jouneau Pierre‐Henri 
Published: February 2020

AbstractFailure mechanisms associated with silicon‐based anodes are limiting the implementation of high‐capacity lithium‐ion batteries. Understanding the aging mechanism that deteriorates the anode performance and introducing novel‐architectured composites offer new possibilities for improving the functionality of the electrodes. Here, the characterization of nano‐architectured composite anode composed of active amorphous silicon domains (a‐Si, 20 nm) and crystalline iron disilicide (c‐FeSi2, 5–15 nm) alloyed particles dispersed in a graphite matrix is reported. This unique hierarchical architecture yields long‐term mechanical, structural, and cycling stability. Using advanced electron microscopy techniques, the nanoscale morphology and chemical evolution of the active particles upon lithiation/delithiation are investigated. Due to the volumetric variations of Si during lithiation/delithiation, the morphology of the a‐Si/c‐FeSi2 alloy evolves from a core‐shell to a tree‐branch type structure, wherein the continuous network of the active a‐Si remains intact yielding capacity retention of 70% after 700 cycles. The root cause of electrode polarization, initial capacity fading, and electrode swelling is discussed and has profound implications for the development of stable lithium‐ion batteries.
Ten‐Gram‐Scale Facile Synthesis of Organogadolinium Complex Nanoparticles for Tumor Diagnosis
Authors: Wei Zhenni , Jiang Zhenqi , Pan Chunshu , Xia Jianbi , Xu Kaiwei , Xue Ting , Yuan Bo , Akakuru Ozioma Udochukwu , Zhu Chengjie , Zhang Guilong , Mao Zheng , Qiu Xiaozhong , Wu Aiguo , Shen Zheyu 
Published: February 2020

AbstractThe market of available contrast agents for clinical magnetic resonance imaging (MRI) has been dominated by gadolinium (Gd) chelates based T1 contrast agents for decades. However, there are growing concerns about their safety because they are retained in the body and are nephrotoxic, which necessitated a warning by the U.S. Food and Drug Administration against the use of such contrast agents. To ameliorate these problems, it is necessary to improve the MRI efficiency of such contrast agents to allow the administration of much reduced dosages. In this study, a ten‐gram‐scale facile method is developed to synthesize organogadolinium complex nanoparticles (i.e., reductive bovine serum albumin stabilized Gd‐salicylate nanoparticles, GdSalNPs‐rBSA) with high r1 value of 19.51 mm−1 s−1 and very low r2/r1 ratio of 1.21 (B0 = 1.5 T) for high‐contrast T1‐weighted MRI of tumors. The GdSalNPs‐rBSA nanoparticles possess more advantages including low synthesis cost (≈0.54 USD per g), long in vivo circulation time (t1/2 = 6.13 h), almost no Gd3+ release, and excellent biosafety. Moreover, the GdSalNPs‐rBSA nanoparticles demonstrate excellent in vivo MRI contrast enhancement (signal‐to‐noise ratio (ΔSNR) ≈ 220%) for tumor diagnosis.
Promoting Student Agency in Writing
Authors: Barnes Jill 
Published: February 2020

AbstractWith increasing expectations on students regarding written communication, the promotion of student agency in writing is more important now than ever. Teachers must find ways to engage and empower all learners throughout the writing process so they can produce authentic and meaningful writing independently. To promote such agency, educators must allow students to do more of the work, even while scaffolding for students who need more support. Supporting students in ways that promote metacognition, using their own voice and ideas, pinpointing their individual needs, and encouraging student leadership throughout the writing process kindle students’ capacity and inclination to take initiative for their own achievement. The author presents strategies that teachers can use to promote student metacognition and agency during the writing processes while allowing students to keep their own writing identity and build independence.
NMR based metabolomic approach for evaluation of Vietnamese honey
Authors: Luong Dang Vu , Tam Nguyen Quang , Xuan Do Thi Thanh , Tai Nguyen Tien 
Published: February 2020

AbstractHoney represents a natural, agricultural product endowed with valuable nutritional and pharmacological functions. Therefore, the classification and evaluation of honey has always been a challenge for chemical analysis, especially when honey adulteration is increasing. The traditional methods for quality control of honey is currently based on physicochemical methods, which is often relatively high cost and time‐consuming. NMR based metabolomics is a metabolomic fingerprinting approach for NMR data using chemometric tools. This combined approach can be apply in food analysis for origin discrimination, biomarker discovery and authenticity screening. The present study demonstrated the capability of the 1H NMR based metabolomics for evaluation of 27 NMR spectra of 09 selected honey samples from Viet Nam. 1H NMR analysis was conducted immediately on collected honey samples, without extraction. Unsupervised PCA multivariate data analysis, applied on 1H NMR experimental data, used to characterize and classify honey samples according to their origin and quality. Different metabolites specific for each botanical origins of honey samples also determined. The obtained results of the demonstration suggests that this combined approach could be useful to develop generally applicable metabolomic approaches to valuate honey products as well as other agricultural products.
Substituent effects on antioxidant activity of monosubstituted indole‐3‐carbinols: A DFT study
Authors: Van Quan Vo , Phu Ho Thi , Thao Pham Thi Thu , Nam Pham Cam 
Published: February 2020

AbstractIndole‐3‐carbinol (I3C) is an indole compound with proven health benefits and thus potential preventive medicine and therapeutic applications. Here the origins of the substituent effects on the antioxidant activity of monosubstituted indole‐3‐carbinols (I3Cs) were studied in silico by calculating their thermochemical properties using the (RO)B3LYP/6‐311++G(2df,2p)//B3LYP/6‐311G(d,p) model chemistry. It was found that the electron withdrawing groups such as CF3, CN, COOH, COOMe can increase the bond dissociation energy (BDE) values of N‐H bonds and decrease the BDE(C8‐H) values, while the presence of the Br, Cl, F, Me, NMe2, NH2, NHMe, OH, OMe, Ph groups seems to decline the BDE(X‐H)s (X = N, C). It is worth noticing that a sequential electron transfer mechanism is responsible for these I3Cs with the strong electron donating groups including NMe2, NHMe and NH2, while a hydrogen atom transfer mechanism is likely favored for the remaining monosubstituted I3Cs. The kinetic study according to the HAT mechanism showed that the CH3OO• radical scavenging of 2‐NMe2‐I3C derivative has the highest rate constant (k = 1.93×1010 M‐1s‐1) and it is higher than that of typical antioxidants i.e. Trolox or ascorbic acid. Thus, the results appear to suggest that the N‐Br‐I3C and 2‐NMe2‐I3C compounds are potential antioxidants.
Study to improve the properties of polylactic acid by epoxidized crude rubber seed oil
Authors: Thuy Nguyen Thi , Nam Bui Xuan , Duc Vu Minh 
Published: February 2020

AbstractThe polylactic acid plasticized by epoxidized crude rubber seed oil (EcRSO) was prepared by using a Brabender mixer to improve the ductility of polylactic acid (PLA). The weight ratios of PLA/EcRSO were changed from 100/0 to 90/10. The tensile properties proved that the addition of EcRSO to PLA led to a strong increase in elongation at break (815 %) and a very strong increase in tensile toughness (1370 %), but a decrease in tensile strength. The plasticization of PLA with EcRSO lowered the Tg as well as cold‐crystallization temperature. The initial weight loss temperature grew from 261.8 to 308.8 oC and the weight loss at 380 oC of PLA reduced from 90.9 to 83.2 % with the presence of 5 wt.% EcRSO. Based on the overall results of this investigation, EcRSO could be used as an environmental friendly plasticizer to replace petroleum‐based plasticizers in improvement the overall properties of PLA.
Transition metal oxides as Pt‐free counter electrodes for liquid‐junction photovoltaic devices
Authors: Dao Van‐Duong , Quang Dang Viet , Vu Ngoc Hung , Vu Hong Ha Thi , Hoa Nguyen Duc , Duoc Vo Thanh , Van Hieu Nguyen , Nguyen Thi Hanh , Tran Nam Anh 
Published: February 2020

AbstractThis work presents the synthesis of the transition metal oxides (micro‐wheels composed of self‐assembled WO3 nanorods, SnO2 nanosheets, and Fe2O3 nanoparticles) by hydrothermal method. The synthesized catalysts are then applied for the regeneration of iodide ions from triiodide ions at counter electrodes (CEs) of dye‐sensitized solar cells (DSCs). As the results, the DSCs with low‐cost catalysts as WO3, SnO2, and Fe2O3 provided an efficiency of 4.36, 4.37 and 1.54 %, respectively, under 1 sun irradiation that is slightly lower than that of a cell with Pt electrode (5.86 %). This behavior is elucidated by electrochemical impedance measurements. These findings provide a strategy to develop low‐cost materials for DSC application.
Antioxidant vs. pro‐oxidant activities of quercetin in aqueous phase: A Density Functional Theory study
Authors: Thao Tran Hoang Dieu , Dung Vo Thi Ngoc , Dao Duy Quang 
Published: February 2020

AbstractThe antioxidant potential of quercetin (Quer) has been investigated for its radical scavenging activity and Cu(II) ion chelating one. Two intrinsic reactivities including bond dissociation enthalpy (BDE) and proton affinity (PA) were systematically calculated in water at the M05‐2X/6‐311++G(d,p) level of theory. All possible hydrated Quer–Cu(II) complexes were also performed to consider its indirect antioxidant activity via the meal ion chelation capacity. Furthermore, reaction enthalpies as well as Gibbs free energies of reactions between Quer‐Cu(II) complexes with O2•‐ and ascorbate anion (Asc‐) in forming corresponding Quer‐Cu(I) ones have also been investigated to draw the larger picture on reduction potential of Cu(II)to Cu(I) ions which may involve in Fenton‐like reactions leading to HO• radical formation.
Comparison of Merriam's Turkey Harvest Strategies and Survival in Northern Arizona
Authors: McCall Thomas C. , Clement Matthew J. , Wakeling Brian F. 
Published: February 2020

ABSTRACTWe compared annual survival and hunting‐related mortality of female Merriam's turkey (Meleagris gallopavo merriami) between a period of relatively liberal hunting regulation (before 1990) and after implementation of a more conservative hunting regulation (after 1991) in Arizona, USA, to determine how those regulation changes affected hunting opportunity. Between January 2013 and October 2016, we used radiotelemetry to estimate survival and mortality rates of 185 female wild turkeys (60 juvenile, 125 adult) on 3 study areas in northern Arizona, which we compared with survival and mortality rates documented during an earlier study (1987–1990; Wakeling 1991). We used the nest survival approach in Program MARK to estimate survival and mortality rates for turkeys. Annual survival rate for radiomarked hens was 0.649 (95% CI = 0.597–0.702). Annual survival differed among Game Management Units, but not by season, year, age, or age × season interaction. Harvest rates were 0.024 (95% CI = 0.011–0.51) and 0.039 (95% CI = 0.022–0.071) for females during spring (Mar–May) and fall (Aug–Oct), respectively. The overall human‐caused mortality rate (i.e., fall harvest, spring harvest, unlawful take, wounding loss) was 0.073 (95% CI = 0.046–0.115). The decision to restrict fall turkey hunting opportunities using a regulated permit system had little effect on female turkey survival and hunting‐related mortality, but reduced the number of turkey hunters that could participate by 43%. © 2020 The Wildlife Society.
Bulk reconstruction for spinor fields in AdS/CFT
Authors: Foit Valentino F. , Kabat Daniel , Lifschytz Gilad 
Published: February 2020

Abstract
We develop the representation of free spinor fields in the bulk of Lorentzian anti-de Sitter space in terms of smeared operators in the dual conformal field theory. To do this we expand the bulk field in a complete set of normalizable modes, work out the extrapolate dictionary for spinor fields, and show that the bulk field can be reconstructed from its near-boundary behavior. In some cases chirality and reality conditions can be imposed in the bulk. We study the action of the CFT modular Hamiltonian on bulk fermions to show that they transform with the expected spinor Lie derivative, and we calculate bulk-boundary two-point functions starting from CFT correlators.
Stability of neuronal avalanches and long-range temporal correlations during the first year of life in human infants
Authors: Jannesari Mostafa , Saeedi Alireza , Zare Marzieh , Ortiz-Mantilla Silvia , Plenz Dietmar , Benasich April A. 
Published: February 2020

AbstractDuring infancy, the human brain rapidly expands in size and complexity as neural networks mature and new information is incorporated at an accelerating pace. Recently, it was shown that single-electrode EEG in preterms at birth exhibits scale-invariant intermittent bursts. Yet, it is currently not known whether the normal infant brain, in particular, the cortex, maintains a distinct dynamical state during development that is characterized by scale-invariant spatial as well as temporal aspects. Here we employ dense-array EEG recordings acquired from the same infants at 6 and 12 months of age to characterize brain activity during an auditory odd-ball task. We show that suprathreshold events organize as spatiotemporal clusters whose size and duration are power-law distributed, the hallmark of neuronal avalanches. Time series of local suprathreshold EEG events display significant long-range temporal correlations (LRTCs). No differences were found between 6 and 12 months, demonstrating stability of avalanche dynamics and LRTCs during the first year after birth. These findings demonstrate that the infant brain is characterized by distinct spatiotemporal dynamical aspects that are in line with expectations of a critical cortical state. We suggest that critical state dynamics, which theory and experiments have shown to be beneficial for numerous aspects of information processing, are maintained by the infant brain to process an increasingly complex environment during development.
InvestRM – Investieren in Rohstoffe am Balkan
Authors: Haindl Angelika 
Published: February 2020

ZusammenfassungDer Balkan ist ein Gebiet mit geologischem Potential, besonders für die Selbstversorgung Europas mit kritischen Rohstoffen. In der gesamten Region fehlen relevante, gut aufbereitete Daten im Rohstoffsektor. Vorhandene Informationen über Vorkommen und Lagerstätten sind nicht immer objektiv, neutral und verifiziert. Dies macht es für Investoren schwierig, Investitionskalkulationen auf einer profunden Datenbasis durchzuführen. Genau hier setzt die Idee von „InvestRM“ an.Am Beispiel Bosniens und Herzegowinas wird im Zuge des Projektes ein Online-Werkzeug entwickelt, welches auf eine umfangreche Datenbank aufbaut, die strukturierte Landesdaten sowie validierte geologische Informationen von rund 120 Vorkommen und Lagerstätten kritischer Rohstoffe enthält. Dabei handelt es sich um Vorkommen und Lagerstätten für den Abbau von Antimon, Bauxit (als Quelle für Seltene Erden), Fluorit und Magnesit.Abgefragte Daten werden in wenigen Sekunden in einem PDF-Bericht in englischer Sprache zusammengestellt. Der Anwender erhält einen verlässlichen, modern aufbereiteten Auszug, welcher als Entscheidungsgrundlage für Investitionen fungieren kann.Aktuell befindet sich das InvestRM-Tool gerade in der Testphase. Online, unter https:\\test.investrm.eu, können Interessierte bereits Berichte erstellen. Neben der Entwicklung des Webportals sind im Projekt auch Projektteam-Treffen und Informationstage (in Banja Luka, Prijedor, Tuzla und Zenica) eingeplant.