bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methods for Exerting and Sensing Force in Polymer Materials Using Mechanophores
Authors: Stratigaki Maria , Göstl Robert 
Published: January 2020

AbstractIn recent years, polymer mechanochemistry has evolved as a methodology to provide insights into the action‐reaction relationships of polymers and polymer‐based materials and composites in terms of macroscopic force application (stress) and subsequent deformation (strain) through a mechanophore‐assisted coupling of mechanical and chemical phenomena. The perplexity of the process, however, from the viewpoint of mechanophore activation via a molecular‐scaled disruption of the structure that yields a macroscopically detectable optical signal, renders this otherwise rapidly evolving field challenging. Motivated by this, we highlight here recent advancements of polymer mechanochemistry with particular focus on the establishment of methodologies for the efficient activation and quantification of mechanophores and anticipate to aptly pinpoint unresolved matters and limitations of the respective approaches, thus highlighting possible developments.
Can We Rely on Results From IQVIA Medical Research Data UK Converted to the Observational Medical Outcome Partnership Common Data Model?
Authors: Candore Gianmario , Hedenmalm Karin , Slattery Jim , Cave Alison , Kurz Xavier , Arlett Peter 
Published: January 2020

Exploring and combining results from more than one real‐world data (RWD) source might be necessary in order to explore variability and demonstrate generalizability of the results or for regulatory requirements. However, the heterogeneous nature of RWD poses challenges when working with more than one source, some of which can be solved by analyzing databases converted into a common data model (CDM). The main objective of the study was to evaluate the implementation of the Observational Medical Outcome Partnership (OMOP) CDM on IQVIA Medical Research Data (IMRD)‐UK data. A drug utilization study describing the prescribing of codeine for pain in children was used as a case study to be replicated in IMRD‐UK and its corresponding OMOP CDM transformation. Differences between IMRD‐UK source and OMOP CDM were identified and investigated. In IMRD‐UK updated to May 2017, results were similar between source and transformed data with few discrepancies. These were the result of different conventions applied during the transformation regarding the date of birth for children younger than 15 years and the start of the observation period, and of a misclassification of two drug treatments. After the initial analysis and feedback provided, a rerun of the analysis in IMRD‐UK updated to September 2018 showed almost identical results for all the measures analyzed. For this study, the conversion to OMOP CDM was adequate. Although some decisions and mapping could be improved, these impacted on the absolute results but not on the study inferences. This validation study supports six recommendations for good practice in transforming to CDMs.
Mechanistic Population Pharmacokinetic Model of Oseltamivir and Oseltamivir Carboxylate Accounting for Physiological Changes to Predict Exposures in Neonates and Infants
Authors: Gibiansky Leonid , Ravva Patanjali , Parrott Neil J. , Bhardwaj Rajinder , Zwanziger Elke , Grimsey Paul , Clinch Barry , Sturm Stefan 
Published: January 2020

A mechanistic population‐pharmacokinetic model was developed to predict oseltamivir exposures in neonates and infants accounting for physiological changes during the first 2 years of life. The model included data from 13 studies, comprising 436 subjects with normal renal function (317 pediatric subjects (≥ 38 weeks postmenstrual age (PMA), ≥ 13 days old) and 119 adult subjects < 40 years). Concentration–time profiles of oseltamivir and its active metabolite, oseltamivir carboxylate (OC), were characterized by a four‐compartment model, with absorption described by three additional compartments. Renal maturational changes were implemented by description of OC clearance with allometric function of weight and Hill function of PMA. Clearance of OC increased with weight up to 43 kg (allometric coefficient 0.75). Half the adult OC clearance was reached at a PMA of 45.6 weeks (95% confidence interval (CI) 41.6–49.6) with a Hill coefficient of 2.35 (95% CI 1.67–3.04). The model supports the European Union/United States‐approved 3 mg/kg twice‐daily oseltamivir dose for infants < 1 year (PMA ≥ 38 weeks) and allows prediction of exposures in preterm neonates.
Reversible Tricolor Mechanochromic Luminescence in Anthranyl π‐Conjugates by Varying the Number of Methoxy Substituents: A Structure‐Property Relationship Study
Authors: Prusti Banchhanidhi , Aggarwal Himanshu , Chakravarty Manab 
Published: January 2020

AbstractConsidering the demand and challenges ahead in the development of new and easily accessible small molecules as mechano(piezo)fluorochromic aggregation‐induced emission active fluorogens (PAIEgens), 1,3,5‐trimethoxybenzene is conveniently connected to anthracene and linked to mono‐N‐alkyl‐phenothiazine with different alkyl chain lengths via a facile, low‐cost and metal‐free synthetic route. These unsymmetrical π‐conjugates are established as small blue‐shifted AIEEgens (AIEE=aggregation‐induced enhanced emission) that exhibit tricolor switching with a sharp PL (photoluminescence or fluorescence) color change (48 nm red‐shift) from green‐to‐yellow on grinding and yellow‐to‐reddish upon thermal annealing at 150 °C. The color change is found to be reversible on exposure to solvent vapor. The role of the trimethoxy groups and N‐alkylphenothiazine core to achieve PAIEE is demonstrated by analyzing its molecular structure and crystal packing with various intermolecular interactions. The structure‐property relationship study shows the significant role of the combination of trimethoxy groups and phenothiazine cores for this system. A variation on the destruction and creation of different crystal facets under different external stimuli are identified through powder X‐ray diffraction studies. The existence of different metastable states is also captured by the appearance of exothermic peaks in the differential scanning calorimetry experiments. Such PAIEgens are shown to be useful as a platform with “write‐erase‐write” functions in security writing and anti‐counterfeiting applications under external stimuli.
Enhanced drought tolerance with artificial microRNA‐mediated StProDH1 gene silencing in potato
Authors: Li Shigui , Zhang Ning , Zhu Xi , Ma Rui , Yang Jiangwei , Tang Xun , Si Huaijun 
Published: January 2020

AbstractProline is a multifunctional molecule, which especially is associated with response to abiotic stress. The proline dehydrogenase (ProDH) is the rate‐limiting enzyme in the process of proline catabolism. In the present study, two potato ProDH genes, StProDH1 and StProDH2, were cloned from potato (Solanum tuberosum L.) cultivar ‘Favorita’. Gene expression analysis indicated that these two genes exhibited tissue‐specific expression and responded differently to various stress conditions, and that the StProDH1 plays a predominant role in most of these conditions. An artificial microRNA expression vector, under the control of CaMV 35S promoter, was constructed to generate transgenic potato plants by Agrobacterium‐mediated transformation, thereby silencing the StProDH1 gene. The result showed that the artificial microRNA caused a decline in StProDH1 expression, which was accompanied by a concomitant increase in proline content in transgenic plants under drought stress. The transgenic potato plants showed normal phenotypes under drought stress, while the non‐transgenic plants appeared withered. Results of physiological parameters assays showed that malondialdehyde, relative water content, and chlorophyll content in the transgenic potato plants were higher than that of non‐transgenic plants. Upon rehydration after two weeks of drought, proline and soluble sugar contents of the transgenic potato plants were significantly higher than those of non‐transgenic plants. These results combined demonstrate that the StProDH1 is a key player in the process of potato response to drought stress.
A Metal‐Free Donor–Acceptor Covalent Organic Framework Photocatalyst for Visible‐Light‐Driven Reduction of CO2with H2O
Authors: Lei Kai , Wang Di , Ye Liqun , Kou Mingpu , Deng Yu , Ma Zhaoyu , Wang Li , Kong Yan 
Published: January 2020

AbstractVisible‐light‐driven CO2reduction to valuable chemicals without sacrificial agents and cocatalysts remains challenging, especially for metal‐free photocatalytic systems. Herein, a novel donor–acceptor (D–A) covalent organic framework (CT‐COF) was constructed by the Schiff‐base reaction of carbazole‐triazine based D–A monomers and possessed a suitable energy band structure, strong visible‐light‐harvesting, and abundant nitrogen sites. CT‐COF as a metal‐free photocatalyst could reduce CO2with gaseous H2O to CO as the main carbonaceous product with approximately stoichiometric O2evolution under visible‐light irradiation and without cocatalyst. The CO evolution rate (102.7 μmol g−1 h−1) was 68.5 times that of g‐C3N4under the same conditions. In situ Fourier‐transform (FT)IR analysis indicated that CT‐COF could adsorb and activate the CO2and H2O molecules and that COOH* species may be a key intermediate. DFT calculations suggested that nitrogen atoms in the triazine rings may be photocatalytically active sites.
Tunnel FET‐based ultralow‐power and hardware‐secure circuit design considering p‐i‐n forward leakage
Authors: Japa Aditya , Majumder Manoj Kumar , Sahoo Subhendu K. , Vaddi Ramesh 
Published: January 2020

SummaryTunnel field‐effect transistor (TFET) exhibits significant p‐i‐n forward leakage with the increase in drain‐to‐source voltage bias, and this adversely impacts the power consumption and reliability of TFET digital circuits. This work presents low‐power circuit techniques that result in novel compact gates and recommends tristate gates to mitigate the leakage effects. The proposed novel compact gates and tristate gates demonstrate two and six times lower power consumption compared with conventional TFET transmission gates with enhanced reliability. Further, this work introduces a new design methodology that leverages TFET p‐i‐n forward leakage for hardware obfuscation applications. Utilizing the proposed design methodology, the optimization of 40% and 80% in area and power consumption of hardware security primitives like true random number generators is also accomplished.
Development of vertical and forward jumping skills in typically developing children in the context of referent control of motor actions
Authors: Chan‐Viquez Daniela , Hasanbarani Fariba , Zhang Lei , Anaby Dana , Turpin Nicolas A. , Lamontagne Anouk , Feldman Anatol G. , Levin Mindy F. 
Published: January 2020

AbstractThe empirically based referent control theory of motor actions provides a new framework for understanding locomotor maturation. Mature movement patterns of referent control are characterized by periods of minimization of activity across multiple muscles (global electromyographic [EMG] minima) resulting from transient matching between actual and referent body configurations. We identified whether locomotor maturation in young children was associated with (a) development of referent control and (b) children's frequency of participation in everyday activities evaluated by parents. Kinematics and EMG activity were recorded from typically developing children (n = 15, 3–5 years) and young adults (n = 10, 18–25 years) while walking, vertical or forward jumping. Presence and location of global EMG minima in movement cycles, slopes of ankle vertical/sagittal displacements, and shoulder displacement ratios were evaluated. Children had fewer global EMG minima compared to adults during specific phases of vertical and forward jumps. Ankle displacement profiles for walking and jumping forward were related to each other in adults, whereas those for walking and vertical jumping were related in children. Higher frequency of participation was significantly correlated with more mature jumping patterns in children. A decrease in the number of global EMG minima and changes in ankle movement patterns could be indicators of locomotor immaturity in typically developing children.
Prevention of foot ulcers in the at‐risk patient with diabetes: a systematic review
Authors: van Netten Jaap J. , Raspovic Anita , Lavery Lawrence A. , Monteiro‐Soares Matilde , Rasmussen Anne , Sacco Isabel C. N. , Bus Sicco A. 
Published: January 2020

AbstractPrevention of foot ulcers in patients with diabetes is important to help reduce the substantial burden on both patient and health resources. A comprehensive analysis of reported interventions is needed to better inform healthcare professionals about effective prevention. The aim of this systematic review is to investigate the effectiveness of interventions to help prevent both first and recurrent foot ulcers in persons with diabetes who are at risk for this complication. We searched the available medical scientific literature in PubMed, EMBASE, CINAHL, and the Cochrane databases for original research studies on preventative interventions. We screened trial registries for additional studies not found in our search and unpublished trials. Two independent reviewers assessed data from controlled studies for methodological quality, and extracted and presented this in evidence and risk of bias tables. From the 13,490 records screened, 35 controlled studies and 46 non‐controlled studies were included. Few controlled studies, which were of generally low to moderate quality, were identified on the prevention of a first foot ulcer. For the prevention of recurrent plantar foot ulcers, there is benefit for the use of daily foot skin temperature measurements, and for therapeutic footwear with demonstrated plantar pressure relief, provided it is consistently worn by the patient. For prevention of ulcer recurrence, there is some evidence for providing integrated foot care, and no evidence for a single session of education.Surgical interventions have been shown effective in selected patients, but the evidence base is small. Foot‐related exercises do not appear to prevent a first foot ulcer. A small increase in the level of weight‐bearing daily activities does not seem to increase the risk for foot ulceration. The evidence base to support the use of specific self‐management and footwear interventions for the prevention of recurrent plantar foot ulcers is quite strong. The evidence is weak for the use of other, sometimes widely applied, interventions, and is practically non‐existent for the prevention of a first foot ulcer and non‐plantar foot ulcer.
The role of spines in anthropogenic seed dispersal on the Galápagos Islands
Authors: Johnson Mae K. A. , Johnson Oscar P. J. , Johnson Reagan A. , Johnson Marc T. J. 
Published: January 2020

Abstract

Dispersal has important ecological and evolutionary consequences for populations, but understanding the role of specific traits in dispersal can be difficult and requires careful experimentation. Moreover, understanding how humans alter dispersal is an important question, especially on oceanic islands where anthropogenic disturbance through species introductions can dramatically alter native ecosystems.

In this study, we investigated the functional role of spines in seed dispersal of the plant caltrop (Tribulus cistoides L., Zygophyllaceae) by anthropogenic dispersal agents. We also tested whether humans or wildlife are more important seed dispersers of T. cistoides on the Galápagos.

Tribulus cistoides is found on tropical mainland and oceanic island habitats. The dispersal structure of T. cistoides is called a mericarp, and they are typically protected by one pair of upper spines and a second pair of lower spines, but the presence and size of spines varies within and between populations. On the Galápagos, the upper and lower spines protect mericarps from seed predation by Darwin's finches. We tested whether spines play a dual role in dispersal by factorially manipulating the presence/absence of the upper and lower spines to simulate natural variation in mericarp morphology.

The upper spines greatly facilitated seed dispersal, whereas the lower spines had no discernible effect on dispersal. The presence of upper spines increased dispersal rate on shoes by pedestrians 23‐fold, on fabrics (e.g., towels) and cars by nearly twofold, and the presence of upper spines increased dispersal distance by cars sixfold. When comparing dispersal rates in habitats with high (roads and foot paths) versus low (arid forest) anthropogenic activity, dispersal rates were demonstrably higher in the habitats with more human activity.

These results have important implications for understanding the ecology and evolution of plant dispersal in the Anthropocene. Spines on the fruits of T. cistoides play important functional roles in anthropogenic dispersal, whereas native and introduced wildlife plays a minor role in dispersal on inhabited islands of the Galápagos. Our results imply that seed predators and humans are jointly shaping the ecology and evolution of contemporary populations of T. cistoides on the Galápagos.
Ecological response to altered rainfall differs across the Neotropics
Authors: Srivastava Diane S. , Céréghino Régis , Trzcinski M. Kurtis , MacDonald A. Andrew M. , Marino Nicholas A. C. , Mercado Dimaris Acosta , Leroy Céline , Corbara Bruno , Romero Gustavo Q. , Farjalla Vinicius F. , Barberis Ignacio M. , Dézerald Olivier , Hammill Edd , Atwood Trisha B. , Piccoli Gustavo C. O. , Ospina-Bautista Fabiola , Carrias Jean‐François , Leal Juliana S. , Montero Guillermo , Antiqueira Pablo A. P. , Freire Rodrigo , Realpe Emilio , Amundrud Sarah L. , de Omena Paula M. , Campos Alice B. A. 
Published: January 2020

AbstractThere is growing recognition that ecosystems may be more impacted by infrequent extreme climatic events than by changes in mean climatic conditions. This has led to calls for experiments that explore the sensitivity of ecosystems over broad ranges of climatic parameter space. However, because such response surface experiments have so far been limited in geographic and biological scope, it is not clear if differences between studies reflect geographic location or the ecosystem component considered. In this study, we manipulated rainfall entering tank bromeliads in seven sites across the Neotropics, and characterized the response of the aquatic ecosystem in terms of invertebrate functional composition, biological stocks (total invertebrate biomass, bacterial density) and ecosystem fluxes (decomposition, carbon, nitrogen). Of these response types, invertebrate functional composition was the most sensitive, even though, in some sites, the species pool had a high proportion of drought‐tolerant families. Total invertebrate biomass was universally insensitive to rainfall change because of statistical averaging of divergent responses between functional groups. The response of invertebrate functional composition to rain differed between geographical locations because (1) the effect of rainfall on bromeliad hydrology differed between sites, and invertebrates directly experience hydrology not rainfall and (2) the taxonomic composition of some functional groups differed between sites, and families differed in their response to bromeliad hydrology. These findings suggest that it will be difficult to establish thresholds of “safe ecosystem functioning” when ecosystem components differ in their sensitivity to climatic variables, and such thresholds may not be broadly applicable over geographic space. In particular, ecological forecast horizons for climate change may be spatially restricted in systems where habitat properties mediate climatic impacts, and those, like the tropics, with high spatial turnover in species composition.
Metal‐free graphene/boron nitride heterointerface for CO2 reduction: Surface curvature controls catalytic activity and selectivity
Authors: Mao Xin , Wijethunge Dimuthu , Zhang Lei , Wang Sufan , Yan Cheng , Zhu Zhonghua , Du Aijun 
Published: January 2020

AbstractSearching environmentally friendly and low‐cost catalysts for CO2 reduction is critical for the development of sustainable energy and environmental technologies. In this work, we report a novel heterointerface between graphene and BN nanotubes or nanoribbons as efficient catalysts for CO2 reduction with high activity and selectivity. The active sites are found to be at the C‐N interfaces of graphene‐BN (G‐BN) and their excellent catalytic performance is derived from the surface curvature effect. The density functional theory (DFT) results reveal that the most energy favorable pathway for the formation of CH3OH is * + CO2 → *COOH → *CO → *OCH → *OCH2 → *OCH3 → *CH3OH → * + CH3OH. And the formation of CH4 is through * + CO2 → *COOH → *CO → *OCH → *OCH2 → *OCH3 → *O + CH4 → *OH + CH4 → *H2O + CH4 pathway. Moreover, the calculated results further demonstrate that for the smaller index of G‐BN nanotubes, such as G‐BN (3), the formation of CH3OH product is much easier than the *O intermediate and CH4 molecule due to the lower free energy change. However, for the higher indexed G‐BN nanotubes, after forming *OCH3 intermediate, the generation of *O and CH4 molecule is more feasible, particularly for G‐BN (9), and the calculated limiting potential is only −0.42 V, which is higher than the best Cu‐based materials, like −0.93 V on Cu(111), and −0.74 V on Cu (211). This metal free heterostructure is confirmed to facilitate CO2 conversion with high activity and selectivity, demonstrating a great potential as a new type of catalyst for CO2 reduction.image
Single vs double atom catalyst for N2 activation in nitrogen reduction reaction: A DFT perspective
Authors: Qian Yumin , Liu Yuanyue , Zhao Yu , Zhang Xiaohong , Yu Guihua 
Published: January 2020

AbstractAmmonia synthesis through electrochemical reduction of nitrogen molecules is a promising strategy to significantly reduce the energy consumption in traditional industrial process. Detailed mechanism study of multistep complex nitrogen reduction reaction is prerequisite for the design of highly efficient catalyst. Stable atomically dispersed catalyst with unique geometric and electronic structure is suitable for the mechanism clarification of such a complex reaction. In this study, d‐block transition‐metal (TM) anchored C2N single layer catalyst is investigated by the density functional theory (DFT) calculation. Both single TM‐anchored single atom catalyst (SAC) and double TM‐anchored double atom catalyst (DAC) exhibit good thermodynamic stability in atomically dispersed catalyst. In the case of SACs, IVB metals (Ti, Zr, Hf) exhibit the highest reactivity and lowest overpotential. While in the case of DACs, Cr─Cr system leads to the NH3 formation, but V─V system leads to the N2H4 formation. The SACs show much lower overpotential and stronger activation of N2 molecule than the DACs due to the different activation mechanisms: traditional σ‐donation/π‐backdonation N2 activation mechanism is found in SACs, while a new π‐donation/π‐backdonation N2 activation mechanism is found in the DACs. The present work demonstrates that the different catalytic effect for NRR between SAC and DAC and their corresponding electronic structure origin, which gives more insight into the single atom catalyst.image