bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective Modification of Ribosomally Synthesized and Post‐Translationally Modified Peptides (RiPPs) through Diels–Alder Cycloadditions on Dehydroalanine Residues
Authors: de Vries Reinder H. , Viel Jakob H. , Oudshoorn Ruben , Kuipers Oscar P. , Roelfes Gerard 
Published: July 2019

AbstractWe report the late‐stage chemical modification of ribosomally synthesized and post‐translationally modified peptides (RIPPs) by Diels–Alder cycloadditions to naturally occurring dehydroalanines. The tail region of the thiopeptide thiostrepton could be modified selectively and efficiently under microwave heating and transition‐metal‐free conditions. The Diels–Alder adducts were isolated and the different site‐ and endo/exo isomers were identified by 1D/2D 1H NMR. Via efficient modification of the thiopeptide nosiheptide and the lanthipeptide nisin Z the generality of the method was established. Minimum inhibitory concentration (MIC) assays of the purified thiostrepton Diels–Alder products against thiostrepton‐susceptible strains displayed high activities comparable to that of native thiostrepton. These Diels–Alder products were also subjected successfully to inverse‐electron‐demand Diels–Alder reactions with a variety of functionalized tetrazines, demonstrating the utility of this method for labeling of RiPPs.
Batch Versus Flow Lithiation–Substitution of 1,3,4‐Oxadiazoles: Exploitation of Unstable Intermediates Using Flow Chemistry
Authors: Wong Jeff Y. F. , Tobin John M. , Vilela Filipe , Barker Graeme 
Published: July 2019

Abstract1,3,4‐Oxadiazoles are a common motif in pharmaceutical chemistry, but few convenient methods for their modification exist. A fast, convenient, high yielding and general α‐substitution of 1,3,4‐oxadiazoles has been developed using a metalation‐electrophilic trapping protocol both in batch and under continuous flow conditions in contradiction to previous reports which suggest that α‐metalation of this ring system results in ring fragmentation. In batch, lithiation is accomplished at an industrially convenient temperature, −30 °C, with subsequent trapping giving isolated yields of up to 91 %. Under continuous flow conditions, metalation is carried out at room temperature, and subsequent in flow electrophilic trapping gave up to quantitative isolated yields. Notably, lithiation in batch at room temperature results only in ring fragmentation and we propose that the superior mixing in flow allows interception and exploitation of an unstable intermediate before decomposition can occur.
Short‐term blood pressure changes have a more strong impact on stroke and its subtypes than long‐term blood pressure changes
Authors: Guo Rongrong , Xie Yanxia , Zheng Jia , Wang Yali , Dai Yue , Sun Zhaoqing , Xing Liying , Zhang Xingang , Sun Yingxian , Zheng Liqiang 
Published: July 2019

AbstractBackgroundElevated blood pressure (BP) is closely related to stroke and its subtypes. However, different time periods changes in BP may result in differential risk of stroke.HypothesisShort‐term blood pressure changes have a more strong impact on stroke and its subtypes than long‐term blood pressure changes.MethodsWe designed the study on the effects of short‐ (2008‐2010) and long‐term (2004‐2010) BP changes on stroke events (2011‐2017), including 22 842 and 28 456 subjects, respectively. The difference in β coefficients between short‐ and long‐term BP changes on the effects of stroke were examined using the Fisher Z test.ResultsDuring a median 12.5‐year follow‐up period, 1014 and 1505 strokes occurred in short‐ and long‐term groups. In short‐term group, going from prehypertension to hypertension, the risk of stroke events increased (stroke: hazard ratio [HR] = 1.537 [1.248‐1.894], ischemic stroke: 1.456 [1.134‐1.870] and hemorrhagic stroke: 1.630 [1.099‐2.415]); going from hypertension to prehypertension, the risk of stroke events decreased (stroke:0.757 [0.619‐0.927] and hemorrhagic stroke:0.569 [0.388‐0.835]). Similarly, in long‐term group, going from prehypertension to hypertension, individuals had an increased risk of stroke (1.291, 1.062‐1.569) and hemorrhagic stroke (1.818, 1.261‐2.623); going from hypertension to prehypertension, participants had a decreased risk of stroke (0.825, 0.707‐0.963) and hemorrhagic stroke (0.777, 0.575‐0.949). Furthermore, the effects of BP changes during short‐term period on stroke events were greater than that in long‐term period.ConclusionsShort‐ and long‐terms BP changes were both associated with the risk of stroke events. Furthermore, short‐term BP changes had a stronger impact than did long‐term changes on risk of stroke events.
Synthesis of Plasmin‐Loaded Fe3O4@CaCO3 Nanoparticles: Towards Next‐Generation Thrombolytic Drugs
Authors: Serov Nikita , Prilepskii Artur , Sokolov Alexey , Vinogradov Vladimir 
Published: July 2019

AbstractA major obstacle in the development of the next‐generation of thrombolytic drugs has been the fact that plasmin – a serine protease that dissolves fibrin in blood clots – despite being the only enzyme suitable for the clot cleavage, is still not used in practice due to its rapid inactivation. Here we point to a potential solution to this problem by developing a magnetically controlled system for targeted delivery and recrystallization‐driven release of plasmin showing therapeutic potential.
CO2 Reduction of Hybrid Cu2O–Cu/Gas Diffusion Layer Electrodes and their Integration in a Cu‐based Photoelectrocatalytic Cell
Authors: de Brito Juliana Ferreira , Genovese Chiara , Tavella Francesco , Ampelli Claudio , Boldrin Zanoni Maria Valnice , Centi Gabriele , Perathoner Siglinda 
Published: July 2019

AbstractCu2O/gas diffusion layer (GDL) electrodes prepared by electrodeposition were studied for the electrocatalytic reduction of CO2. The designed electrode was also tested in solar‐light‐induced CO2 conversion in combination with a CuO/NtTiO2 photoanode using a compact photoelectrocatalytic (PEC) cell. Both PEC cell electrodes were prepared using non‐critical raw materials and low cost, easily scalable procedures. In the PEC experiments, a total carbon faradaic selectivity of about 90 % to formate and about 75 % to acetate was obtained after 24 h of operations without application of potential/current or using sacrificial agents. In electrocatalytic tests of CO2 reduction at −1.5 V, the same electrode yielded high total faradaic selectivity (>95 %) but formed selectively formate (about 80 % selectivity) rather than acetate. The in situ transformation of the Cu2O/GDL electrode leads to the formation of a hybrid Cu2O–Cu/GDL system. Cyclic voltammetry data indicate that the potential and the presence of CO2 (not only of HCO3− species) are both important elements in this transformation. Data also indicate that the surface concentration of CO2 (or of its products of transformation) on the electrode is an important factor to determine performance in the conversion of CO2.
A fuzzy decision scheme for relay selection in cooperative wireless sensor network
Authors: Jain Nitin Kumar , Yadav Dharmendra Singh , Verma Ajay 
Published: July 2019

SummaryIn energy‐constrained military wireless sensor networks, minimizing the bit error rate (BER) with little compromise on network lifetime is one of the most challenging issues. This paper presents a new relay selection based on fuzzy logic (RSFL) scheme which provides balance between these parameters. The proposed scheme considers node's residual energy and path loss of the relay‐destination link as the input parameters for the selection of the relay node. The relay node selection by fuzzy logic is based on prioritizing higher residual energy and minimum path loss. To evaluate the performance on wireless sensor network, we compare the proposed scheme with the three existing relay selection strategies, ie, random, maximum residual energy based relay selection (MaxRes), and minimum energy consumption based relay selection (MinEnCon). The simulation results of the proposed scheme in terms of network lifetime, BER, Network Survivability Index (NSI), and average energy of network nodes have been presented and compared with different relay selection schemes. The simulation results show that the proposed RSFL scheme has the lowest BER, moderate network lifetime, average energy, and NSI.
The interaction of maternal diabetes with mutations that affect folate metabolism and how they affect the development of neural tube defects in mice
Authors: López‐Escobar Beatriz , Wlodarczyk Bogdan J. , Caro‐Vega Jose , Lin Ying , Finnell Richard H. , Ybot‐González Patricia 
Published: July 2019

AbstractBackgroundAbnormalities in maternal folate and carbohydrate metabolism have both been shown to induce neural tube defects (NTDs) in humans and animal models. Nevertheless, how these two factors might interact in the development of NTDs remains unclear.ResultsIn specific mouse models and embryo culture systems, we assessed the effects of combining maternal diabetes with mutations in genes involved in folate transport and metabolism (methylenetetrahydrofolate reductase [Mthfr] and folic acid receptor 1 [Folr1]). When maternal hyperglycemia is combined with alterations in folic acid metabolism, there appears to be an increase in the incidence of congenital malformations in the offspring, with NTDs representing the majority of the malformations detected.ConclusionsThe teratogenic effects of diabetes during pregnancy are exacerbated when combined with altered embryonic folate metabolism.
Comparing generalized and customized spread models for nonnative forest pests
Authors: Hudgins Emma J. , Liebhold Andrew M. , Leung Brian 
Published: July 2019

AbstractWhile generality is often desirable in ecology, customized models for individual species are thought to be more predictive by accounting for context specificity. However, fully customized models require more information for focal species. We focus on pest spread and ask: How much does predictive power differ between generalized and customized models? Further, we examine whether an intermediate “semi‐generalized” model, combining elements of a general model with species‐specific modifications, could yield predictive advantages. We compared predictive power of a generalized model applied to all forest pest species (the generalized dispersal kernel or GDK) to customized spread models for three invasive forest pests (beech bark disease [Cryptococcus fagisuga], gypsy moth [Lymantria dispar], and hemlock woolly adelgid [Adelges tsugae]), for which time‐series data exist. We generated semi‐generalized dispersal kernel models (SDK) through GDK correction factors based on additional species‐specific information. We found that customized models were more predictive than the GDK by an average of 17% for the three species examined, although the GDK still had strong predictive ability (57% spatial variation explained). However, by combining the GDK with simple corrections into the SDK model, we attained a mean of 91% of the spatial variation explained, compared to 74% for the customized models. This is, to our knowledge, the first comparison of general and species‐specific ecological spread models’ predictive abilities. Our strong predictive results suggest that general models can be effectively synthesized with context‐specific information for single species to respond quickly to invasions. We provided SDK forecasts to 2030 for all 63 United States pests in our data set.
Suicidal selection: Programmed cell death can evolve in unicellular organisms due solely to kin selection
Authors: Vostinar Anya E. , Goldsby Heather J. , Ofria Charles 
Published: July 2019

AbstractUnicellular organisms can engage in a process by which a cell purposefully destroys itself, termed programmed cell death (PCD). While it is clear that the death of specific cells within a multicellular organism could increase inclusive fitness (e.g., during development), the origin of PCD in unicellular organisms is less obvious. Kin selection has been shown to help maintain instances of PCD in existing populations of unicellular organisms; however, competing hypotheses exist about whether additional factors are necessary to explain its origin. Those factors could include an environmental shift that causes latent PCD to be expressed, PCD hitchhiking on a large beneficial mutation, and PCD being simply a common pathology. Here, we present results using an artificial life model to demonstrate that kin selection can, in fact, be sufficient to give rise to PCD in unicellular organisms. Furthermore, when benefits to kin are direct—that is, resources provided to nearby kin—PCD is more beneficial than when benefits are indirect—that is, nonkin are injured, thus increasing the relative amount of resources for kin. Finally, when considering how strict organisms are in determining kin or nonkin (in terms of mutations), direct benefits are viable in a narrower range than indirect benefits.Open Research BadgesThis article has been awarded Open Data and Open Materials Badges. All materials and data are publicly accessible via the Open Science Framework at https://github.com/anyaevostinar/SuicidalAltruismDissertation/tree/master/LongTerm.
Aetiology‐based clinical scenarios predict outcomes of transcatheter edge‐to‐edge tricuspid valve repair of functional tricuspid regurgitation
Authors: Schlotter Florian , Orban Mathias , Rommel Karl‐Philipp , Besler Christian , von Roeder Maximilian , Braun Daniel , Unterhuber Matthias , Borger Michael , Hagl Christian , Orban Martin , Nabauer Michael , Massberg Steffen , Thiele Holger , Hausleiter Jörg , Lurz Philipp 
Published: July 2019

AimsTranscatheter tricuspid valve repair (TTVR) is an emerging technique to treat tricuspid regurgitation (TR). Predictors of adverse outcomes are scarce, and stratification by TR aetiologies is lacking.Methods and resultsWe report the bi‐centre procedural outcomes of 164 patients undergoing TTVR for TR stratified into four aetiology‐based clinical scenarios (CSs). By stepwise categorization, patients were categorized into Dialysis‐CS if they were on chronic haemodialysis; patients not undergoing dialysis with MR grade ≥ 3 into MR‐CS; patients not meeting the inclusion into Dialysis‐CS or MR‐CS with an invasively‐determined systolic pulmonary artery pressure ≥ 50 mmHg into PAPs‐CS; and the remaining patients into Afib‐CS in case a history of atrial fibrillation/flutter existed. Clinical characteristics and procedural outcomes were evaluated. Procedural success was > 80% in all CSs and decreased mortality (P = 0.03). Within the group of patients with procedural success, PAPs‐CS had the highest rates of the primary endpoint of death, heart failure hospitalization or reintervention (P = 0.01). Mortality was significantly higher in PAPs‐CS when compared to the other CSs (P = 0.03) and Dialysis‐CS had the highest mortality rate (33.3%). In all CSs, the majority of patients experienced New York Heart Association functional class improvement at follow‐up.ConclusionsStratification of TTVR into aetiology‐based CSs may open new paths to stratify for clinical risk and procedural benefit and may aid in the design of clinical trials in the heterogeneous TTVR patient population. Despite the observed CS outcome differences, TTVR appears feasible and safe, and confers functional improvements in patients with TR and heart failure.
Psychophysical or spinal reflex measures when assessing conditioned pain modulation?
Authors: Lie Marie Udnesseter , Petriu Elena , Matre Dagfinn , Hansson Per , Andersen Ole Kæseler , Zwart John‐Anker , Nilsen Kristian Bernhard 
Published: July 2019

AbstractBackgroundAssessing conditioning pain modulation (CPM) with spinal reflex measures may produce more objective and stable CPM effects than using psychophysical measures. The aim of the study was to compare the CPM effect and test–retest reliability between a psychophysical protocol with thermal test‐stimulus and a spinal reflex protocol with electrical test‐stimulus.MethodsTwenty‐five healthy volunteers participated in two identical experiments separated by minimum 1 week. The thermal test‐stimulus was a constant heat stimulation of 120 s on the subjects’ forearm with continuous ratings of pain intensity on a 10 cm visual analogue scale. The electrical test‐stimulus was repeated electrical stimulation on the arch of the foot for 120 s, which elicited a nociceptive withdrawal reflex recorded from the anterior tibial muscle. Conditioning stimulus was a 7°C water bath. Differences in the magnitude and test–retest reliability were investigated with repeated‐measures analysis of variance and by relative and absolute reliability indices.ResultsThe CPM effect was −46% and 4.5% during the thermal and electrical test‐stimulus (p < 0.001) respectively. Intraclass correlation coefficient of 0.5 and 0.4 was found with the electrical and thermal test‐stimulus respectively. Wide limits of agreement were found for both the electrical (−3.4 to 3.8 mA) and the thermal test‐stimulus (−3.2 to 3.6 cm).ConclusionsMore pronounced CPM effect was demonstrated when using a psychophysical protocol with thermal test‐stimulus compared to a spinal reflex protocol with electrical test‐stimulus. Fair relative reliability and poor absolute reliability (due to high intraindividual variability) was found in both protocols.SignificanceThe large difference in CPM effect between the two protocols suggests that the CPM effect relates to pain perception rather than nociception on the spinal level. Due to poor absolute intrarater reliability, we recommend caution and further research before using any of the investigated CPM protocols in clinical decision making on an individual level.
The software tool to find greener solvent replacements, PARIS III
Authors: Harten Paul , Martin Todd , Gonzalez Michael , Young Douglas 
Published: July 2019

AbstractPARIS III (Program for Assisting the Replacement of Industrial Solvents III, Version 1.4.0) is a pollution prevention solvent substitution software tool used to find mixtures of solvents that are less harmful to the environment than the industrial solvents to be replaced. By searching extensively though hundreds of millions of possible solvent combinations, mixtures that perform the same as the original solvents may be found. Greener solvent substitutes may then be chosen from those mixtures that behave similarly but have less environmental impact. These extensive searches may be enhanced by fine‐tuning impact weighting factors to better reflect regional environmental concerns; and by adjusting how close the properties of the replacement must be to those of the original solvent. Optimal replacements can then be compared again and selected for better performance, but less environmental impact. This method can be a very effective way of finding greener replacements for harmful solvents used by industry.
Hydraulic flushing in soft coal sublayer: Gas extraction enhancement mechanism and field application
Authors: Zhang Hao , Cheng Yuanping , Yuan Liang , Wang Liang , Pan Zhejun 
Published: July 2019

AbstractIn China, one or several ultrathin soft coal sublayers are widely developed in the coal seam. Therefore, a method of using hydraulic flushing in soft sublayer to enhance the gas extraction in these particular coal seams is developed in this work. We first established a new fully coupled gas extraction model by combing gas diffusion, gas flow, and a permeability model that considers the effect of stress change and plastic failure. By adopting this model, the gas extraction enhancement mechanism and its main influence factors were studied using the numerical simulation method based on the engineering and geological background in the Yangquan No.5 coalmine. Thereafter, a hydraulic flushing equipment, which could move freely in the underground coalmine, was developed to apply the hydraulic flushing method in soft coal sublayers used in the 8402 working face. Its gas extraction effect was systematically investigated. Our simulation results match well with the field results, suggesting that our model is feasible. Meanwhile, after adopting this method, the gas extraction condition in this coalmine improves significantly. The borehole number decreases by 66.7%, while the gas extraction rate and gas extraction concentration increase by 1.33 times and 3 times, respectively. Moreover, during the coal mining process, the gas adsorption index of drilling cuttings, the quantity of drilling cuttings, and the CH4 concentration also decrease dramatically.
Towards a trusted unmanned aerial system using blockchain for the protection of critical infrastructure
Authors: Barka Ezedin , Kerrache Chaker Abdelaziz , Benkraouda Hadjer , Shuaib Khaled , Ahmad Farhan , Kurugollu Fatih 
Published: July 2019

AbstractWith the exponential growth in the number of vital infrastructures such as nuclear plants and transport and distribution networks, these systems have become more susceptible to coordinated cyberattacks. One of the effective approaches used to strengthen the security of these infrastructures is the use of unmanned aerial vehicles (UAVs) for surveillance and data collection. However, UAVs themselves are prone to attacks on their collected sensor data. Recently, blockchain (BC) has been proposed as a revolutionary technology that can be integrated within Internet of things (IoT) to provide a desired level of security and privacy. However, the integration of BC within IoT networks, where UAV's sensors constitute a major component, is extremely challenging. The major contribution of this study is twofold:(1) survey the security issues for UAV's collected sensor data, define the security requirements for such systems, and identify ways to address them; and (2) propose a novel BC‐based solution to ensure the security of and the trust between the UAVs and their relevant ground control stations. Our implementation results and analysis show that using UAVs as means for protecting critical infrastructure is greatly enhanced through the utilization of trusted BC‐based unmanned aerial systems.
Influence of liquid accelerant on scaling behavior of stainless steel in fire: An experimental study
Authors: Xie Dongbai , Wang Wen , Duo Shuwang 
Published: July 2019

SummaryAmong the commercial materials, stainless steel is widely used in our daily life and can be hardly destroyed by flame or the heat emanating from a fire. In this fundamental work, the formation and development of oxide scale on stainless steel 1Cr11Ni2W2MoV were investigated at 600°C to 800°C in the atmospheres with and without liquid accelerant. The aim of this work is to figure out the influence of accelerant on the oxidation pattern of stainless steel at high temperature that occurs in a fire. The morphology, microstructure, and the growth rate of the oxide scales were characterized by thermogravimetric analysis, visual analysis, scanning electron microscopy, energy‐dispersive spectroscopy, and X‐ray diffraction. The results revealed that the oxide scale formed on the stainless steel 1Cr11Ni2W2MoV was mostly protective in both atmospheres from 600°C to 800°C, except that breakaway oxidation occurred locally that resulted in the formation of intrusion oxide. Both increasing temperature and the presence of kerosene in combustion atmosphere increased the mass gain of stainless steel, which was mainly attributed to the occurrence of local breakaway oxidation. Consequently, the addition of accelerant just increased the formation trend of local intrusion oxide, rather than remarkably affect the scaling behavior. Therefore, careful analysis is needed to identify the presence possibility of accelerant in oxidation atmosphere according to the scaling behavior of stainless steel. Characterization of surface scale and metallurgical analysis of metallic material are expected to be supplementary technique for fire characterization in the future.