bluuebunny/crossref_metadata_2025_split huggingface dataset:
Racemic Bisindole Alkaloids: Structure, Bioactivity, and Computational Study
Authors: Jin Tian‐Yun , Li Ping‐Lin , Wang Ci‐Li , Tang Xu‐Li , Cheng Mei‐Mei , Zong Yuan , Luo Lian‐Zhong , Ou Hui‐Long , Liu Ke‐Chun , Li Guo‐Qiang 
Published: May 2021

Main observation and conclusionThe new racemic and dimeric indole alkaloids with the characteristic cyclopenta[b]indole backbone, (+)‐ and (–)‐spondomine (1a/1b), were isolated from a cultured sponge Tedania anhelans. A semi‐synthesis was employed to obtain 1a/1b and the other four stereoisomers 1c—1f. Their structures were determined by spectroscopic analysis, single‐crystal X‐ray, and quantum chemical calculations. Six stereoisomers differ in bioactivity according to their absolute configurations. Especially, (+)‐spondomine (1a) displayed cytotoxicity against the K562 cell line and exhibited stronger Wnt and HIF1 dual signaling inhibitory activity at 5 μmol/L than the positive control, which offers an exciting starting point for further investigations. All stereoisomers significantly promoted angiogenesis and showed moderate anti‐inflammation in zebrafish. A quantum chemical calculation and deuteration experiment were applied to unveil the reaction mechanism which guides the synthesis of the target compounds.
The Synergistic Effect of Heteroatom Doping and Vacancy on The Reduction of CO2 by Photocatalysts
Authors: Cui Dandan , Hao Weichang , Chen Jun 
Published: May 2021

AbstractAgainst the backdrop of rapid world economic growth and energy shortages, we are facing a big challenge about carbon‐containing resources converting. To solve the problems of energy and environmental, developing the catalysts to converse the carbon‐containing resources with high‐efficiency is very important. It has been proved that the vacancy and heteroatom doping can promote the activity of photocatalyst to reduce CO2. Herein, we provide a concise overview on the synergistic effects of defect and heteroatom doping about how to improve the activity of photocatalysts to reduce CO2, and to make a future perspective in the synergistic effects of vacancy and heteroatom doping for photocatalytic CO2 reduction.
Indocyanine green versus technetium‐99m with blue dye for sentinel lymph node detection in early‐stage cervical cancer: A systematic review and meta‐analysis
Authors: Baeten Ilse G. T. , Hoogendam Jacob P. , Jeremiasse Bernadette , Braat Arthur J. A. T. , Veldhuis Wouter B. , Jonges Geertruida N. , Jürgenliemk‐Schulz Ina M. , van Gils Carla H. , Zweemer Ronald P. , Gerestein Cornelis G. 
Published: May 2021

AbstractBackgroundThe fluorescent dye indocyanine green (ICG) has emerged as a promising tracer for intraoperative detection of sentinel lymph nodes (SLNs) in early‐stage cervical cancer. Although researchers suggest the SLN detection of ICG is equal to the more conventional combined approach of a radiotracer and blue dye, no consensus has been reached.AimsWe aimed to assess the differences in overall and bilateral SLN detection rates with ICG versus the combined approach, the radiotracer technetium‐99m (99mTc) with blue dye.Methods and ResultsWe searched MEDLINE, Embase, and the Cochrane Library from inception to January 1, 2020 and included studies reporting on a comparison of SLN detection with ICG versus 99mTc with blue dye in early‐stage cervical cancer. The overall and bilateral detection rates were pooled with random‐effects meta‐analyses.From 118 studies retrieved seven studies (one cross‐sectional; six retrospective cohorts) were included, encompassing 589 patients. No significant differences were found in the pooled overall SLN detection rate of ICG versus 99mTc with blue dye. Meta‐analyses of all studies showed ICG to result in a higher bilateral SLN detection rate than 99mTc with blue dye; 90.3% (95%CI, 79.8‐100.0%) with ICG versus 73.5% (95%CI, 66.4‐80.6%) with 99mTc with blue dye. This resulted in a significant and clinically relevant risk difference of 16.6% (95%CI, 5.3‐28.0%). With sensitivity analysis, the risk difference of the bilateral detection rate maintained in favor of ICG but was no longer significant (13.2%, 95%CI −0.8‐27.3%).ConclusionICG appears to provide higher bilateral SLN detection rates compared to 99mTc with blue dye in patients with early‐stage cervical cancer. However, in adherence with the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) guidelines, the quality of evidence is too low to provide strong recommendations and directly omit the combined approach of 99mTc with blue dye.
5G network slicing: Fundamental concepts, architectures, algorithmics, projects practices, and open issues
Authors: Debbabi Fadoua , Jmal Rihab , Chaari Fourati Lamia 
Published: May 2021

SummaryNetwork slicing (NS) presents the key enabler of cellular network improvements. It allows enhancing the performance of diverse requirements supported for verticals industries. The concept of NS was carefully studied over the previous few years, and the primary operational principles were developed. However, there is an important need for more investigations on studying NS to enable further development. This article offers a deep study related to the NS principle, the recent standardization process for Third Generation Partnership Project and Fifth Generation Public Private Partnership, the diverse broad use cases, NS key concepts, NS architectures, and NS management and orchestration. Besides, it discusses radio access network slicing and sharing, the algorithms, the projects, and the NS practical experience and practices. Finally, this article proposes and highlights a possible solution to several open research issues.
The Sulfolene Protecting Group: Observation of a Direct Photoinitiated Cheletropic Ring Opening
Authors: Skov Anders B. , Folkmann Linnea M. , Boguslavskiy Andrey E. , Röder Anja , Lausten Rune , Stolow Albert , Johnson Matthew S. , Pittelkow Michael , Nielsen Ole John , Sølling Theis I. , Hansen Thorsten 
Published: May 2021

AbstractPhotolabile protecting groups offer synthetic routes with facile deprotection by photolysis, providing higher yields with less workup. Protecting groups producing only gaseous byproducts upon removal are particularly desirable as sustainable reagents. Cheletropic reactions provide just this combination of photocleavable groups with gaseous byproducts. However, only few protecting groups for cheletropic reactions have been described and little is known about their photochemistry and associated stereochemistry. Here we show that the sulfolene protecting group, used for diene protection and functionalization, can be photochemically removed. First, using TD‐DFT, we conclude that the photochemical ring‐opening occurs conrotatorily in a concerted process, consistent with the Woodward‐Hoffmann rules. Experimentally, we demonstrate that this process can be photoinitiated by radiation between 180 and 300 nm and confirm the proposed stereochemistry in solution. Using time‐resolved photoelectron spectroscopy, we determine that the first steps in the photochemical ring‐opening of sulfolene occur on ultrafast timescales (≤84 fs), consistent with a fully concerted process. Our findings expand applications of the sulfolene protecting group and promise an easy strategy for control of cis‐trans isomerization.
Measurement of the Effects of Metals on Taxis‐to‐Food Behavior in Caenorhabditis elegans
Authors: Queirós Libânia , Monteiro Luana , Marques Carlos , Pereira Joana L. , Gonçalves Fernando J. M. , Aschner Michael , Pereira Patrícia 
Published: May 2021

AbstractChemosensation in nematodes is linked to processes that affect their ability to survive, such as the search for food and the avoidance of toxic substances. Since the 1970s, numerous studies have assessed chemotaxis in the nematode species Caenorhabditis elegans, focusing on a multitude of agents, including bacteria (food), ions, salts, hormones, volatile organic compounds, and, to a lesser extent, metal‐contaminated medium/food. The few studies evaluating metal exposure have reported a variety of responses (neutral, attraction, avoidance), which generally appear to be contaminant and/or concentration specific. Differences in experimental designs, however, hinder appropriate comparison of the findings and attainment of firm conclusions. Therefore, we herein propose and describe a detailed protocol for the assessment of the effects of metals on taxis‐to‐food behavior in C. elegans. Distinct approaches are proposed in two innovative stages of testing to (1) screen metals’ effects on taxis‐to‐food behavior and (2) classify the behavioral response as attraction/avoidance/indifference or preference. Use of such a standard protocol will allow for easy comparison across studies and direct interpretation of results. Findings using this model system can contribute to a deeper understanding of the real risks of metal contamination to nematodes and how such contaminants could impact ecosystems in general, given the key environmental roles that these organisms play. © 2021 Wiley Periodicals LLC.Basic Protocol: Assessing the effects of metal contamination on taxis‐to‐food behavior in Caenorhabditis elegansSupport Protocol 1: Synchronization of C. elegans by hand‐picking gravid wormsSupport Protocol 2: Synchronization of C. elegans by using a bleaching solution
Physicochemical and Electrochemical Properties of Water‐in‐Salt Electrolytes
Authors: Amiri Mona , Bélanger Daniel 
Published: May 2021

AbstractAqueous electrolytes are attractive for applications in electrochemical technologies due to features like being eco‐friendly, cost effective, and non‐flammable. Very recently, superconcentrated aqueous electrolytes, such as so‐called water‐in‐salt, water‐in‐bisalt, and hydrate melt, have received a significant attention for electrochemical energy storage due to enhanced stability and much wider electrochemical stability window. This Review focuses on the physicochemical properties of the highly concentrated electrolytes that are derived from several analysis techniques and simulation. A summary of most common features such as ions‐water interactions, structure of species present in the electrolyte, conductivity, and viscosity of the electrolytes found in the literature are presented as well. In addition, this Review explains how these characteristics affect the electrochemical behavior of the electrolyte such as double layer structure and electrode/electrolyte interface leading to enhanced electrochemical stability of aqueous electrolytes.
Spatiotemporal seed transfer zones as an efficient restoration strategy in response to climate change
Authors: Marinoni L. , Parra Quijano M. , Zabala J. M. , Pensiero J. F. , Iriondo J. M. 
Published: May 2021

AbstractRestoration of wild plant populations in a changing environment is not a simple task, and it becomes increasingly complex and challenging in the context of climate change. In the present study, a spatiotemporal approach was used to delimit provisional seed transfer zones (STZs), for restoration activities involving two wild perennial grasses in Argentina. Ecogeographical land characterization maps were built specifically for the two species of Trichloris genus for the present bioclimatic conditions to define the different STZs; then, they were projected for two future climate scenarios (2050 and 2070). This allowed us to identify populations occurring in cells that underwent changes in ecogeographical categories, potential future beneficiaries of germplasm, and populations that could be used as corresponding source populations under the present conditions. Finally, the conservation status of populations was surveyed and a germplasm collection for future restoration activities was proposed. For the 2050 scenario, for Trichloris crinita, 32 potential beneficiary populations belonging to nine changing categories were identified, whereas for Trichloris pluriflora, four changing categories determined seven beneficiary populations. The number of changing categories and, consequently, the beneficiary populations increased in the 2070 scenario in both species. Several potential seed source populations are already stored in Argentine germplasm banks, but there is little representation of potential beneficiary populations. Spatial locations of still non‐conserved populations, both seed sources and beneficiaries, were prioritized for future germplasm collecting missions. This novel approach used for Trichloris spp. can also be adopted for other species for collection and/or restoration purposes in the light of climate change.
Between a rock and a hard place: Ovipositing treefrogs navigate complex trade‐offs in the landscape of patch quality
Authors: Resetarits William J. 
Published: May 2021

AbstractColonizing organisms actively choosing habitats face a bewildering array of choices regarding patch quality, whether choosing for themselves, offspring, or both. Decisions are especially critical when selecting patches for long‐term use (demographic habitat selection). Thus, identifying higher quality patches based on available cues, and integrating information across multiple axes of patch quality, is critical to survival, performance, and fitness. Two critical axes of patch quality for ovipositing gray treefrogs, revealed by prior experiments, are predation risk and patch size. We utilized a unique design presenting two, suboptimal patch choices: small fishless pools and large pools with fish. Our goal was to gain an understanding of the relative priority of these two important patch characteristics for treefrogs by presenting only compromise choices and comparing these results to expectations generated by a previous experiment. In the absence of optimal patches, treefrogs increased their use of both large pools with fish and especially small fishless patches, both of which are unused when larger fishless patches are available. These results reaffirm the primacy of predation, especially the presence of fish, vividly illustrating the spatial context dependence of habitat selection behavior, as well as the complexity of the decisions faced by colonizing and ovipositing organisms in complex landscapes.
Cycling performance for storage and purification of lanthanum‐rich mischmetal alloy in the presence of hydrogen sulfide
Authors: Miao Shan , Eguchi Akashi , Katayama Noboru , Dowaki Kiyoshi 
Published: May 2021

AbstractWith the continuous expansion of the high‐purity hydrogen application range, the performance degradation of hydrogen storage alloy (HSA) caused by impurities has attracted widespread attention in producing pure hydrogen from biomass. In this study, the lanthanum‐rich mischmetal alloy's purification ability on hydrogen sulfide impurities and cycling performance were studied. The hydrogen with different concentrations of hydrogen sulfide was used to investigate the purification performance, which assumes the gas derived from biomass. Besides, a cycling experiment was designed to analyze cycling performance. The results show that the HSA could remove high concentrations of hydrogen sulfide entirely. It was also found that impurities of 1 ppm hydrogen sulfide had little effect on the HSA. With hydrogen sulfide concentrations of 100 ppm, the hydrogen storage capacity, absorption rate, and release rate were reduced, but they became a stable state from the second cycle. The performance degradation mechanism was analyzed by Energy Dispersive X‐Ray Spectroscopy (EDS) and X‐ray Photoelectron Spectroscopy (XPS​).
Participation of electric vehicles in auxiliary service market to promote renewable energy power consumption: Case study on deep peak load regulation of auxiliary thermal power by electric vehicles
Authors: Yang Xiaolong , Niu Dongxiao , Sun Lijie , Wang Keke , De Gejirifu 
Published: May 2021

AbstractWith the rapid development of new energy sources and the increasing proportion of electric vehicles (EVs) connected to the power grid in China, peak load regulation of power systems will face severe challenges. Therefore, in this study, we analyzed the relationship between the electricity consumption characteristics of EVs and the peak load regulation (PLR) mechanism of power systems, and we proposed an operation mode for virtual power plants with EVs to participate in the auxiliary service market and facilitate deep peak load regulation in the thermal power units. Based on the electricity demand‐side management theory and cost‐benefit analysis method, we constructed a decision model for economic deep peak load regulated operation (DPLR) of the auxiliary thermal power units in a virtual power plant with EVs, aiming to optimize the operation efficiency. The case study showed that a virtual power plant that included EVs can effectively reduce the total PLR cost of the system and the peak valley difference of the net load as well as improve the economic benefits of the thermal power units. The results indicated that the virtual power plant had improved economic efficiency. Therefore, the results of this research can help improve the PLR capacity of the grid and significantly promote the consumption of intermittent renewable energy.
Spectrally efficient M‐ary QAM based multi‐antenna cooperative system over TWDP fading channel
Authors: Makkar Rahul , Gupta Akshita , Rawal Divyang , Sharma Nikhil 
Published: May 2021

AbstractTo cater the ever‐increasing demand of wireless high‐speed data access and mobile users, one of the potential enablers toward the sustainable improved network capacity is the network densification at different layers of the radio access system. In this article, a possible solution to achieve a spectrally efficient, ultradense network (UDN) for cellular communication is analyzed. In particular, the performance of the generalized M‐ary quadrature amplitude modulation (M‐QAM) scheme for multiantenna cooperative decode‐and‐forward (DF) system over two‐wave with diffuse power (TWDP) fading is presented. The TWDP fading is evaluated using the moment generating function (MGF) based approach on spectral efficient QAM transmission. In this article, novel closed‐form expressions for the exact average symbol error rate (ASER) for the generalized rectangular‐QAM (R‐QAM) and square‐QAM (S‐QAM) schemes are presented. The obtained expressions are in the form of Appell's and Laureicella's confluent hypergeometric function which can be evaluated mathematically either in the series or the integral‐form. Further, the asymptotic analysis is also presented for the considered system to get better insights into the system. The analytical results derived are corroborated by simulations to validate the accuracy of the analysis.
Erucic acid concentration of rapeseed (Brassica napus L.) oils on the German food retail market
Authors: Russo Marco , Yan Feng , Stier Annegret , Klasen Linda , Honermeier Bernd 
Published: May 2021

AbstractRapeseed oil is one of the most important vegetable oils in Germany. It has a favorable fatty acid composition but also contains a certain amount of erucic acid (EA). As the result of toxicological considerations regarding this fatty acid, the European Food Safety Authority (EFSA) established a tolerable daily intake (TDI) for EA of 7 mg/kg body weight in 2016. On this basis, the maximum EA levels for vegetable oils allowed in the European Union have been reduced shortly from 50 to 20 g/kg, and for infant formula and follow‐on formula from 10 to 4 g/kg. However, rapeseed oil is also recommended for the preparation of homemade food for infants and children. Little is known about the actual EA concentrations of rapeseed oils on the German retail market. Current data are especially important for the necessary reassessment of its recommendation in infant and child nutrition based on the established TDI. Three hundred representative rapeseed oil samples were purchased in retail stores across Germany. EA concentrations, determined by GC‐FID, were in a range of 0.17–9.68 g/kg, with 241 samples being even below 4 g/kg. All oils were below the maximum level valid at the time of this investigation, and even below the newly established lower maximum level of 20 g/kg. The major part also met the requirements for infant and follow‐on formula. The representative results provide valuable current data for the necessary reassessment of the dietary recommendations for infant and child nutrition based on the established TDI.
Astroglial Cx30 differentially impacts synaptic activity from hippocampal principal cells and interneurons
Authors: Hardy Eléonore , Cohen‐Salmon Martine , Rouach Nathalie , Rancillac Armelle 
Published: May 2021

AbstractAstrocytes play important roles in brain function via dynamic structural and functional interactions with neurons. Yet the underlying mechanisms remain poorly defined. A typical feature of astrocytes is the high expression of connexins, which mediate their extensive intercellular communication and regulate their structural properties. In particular, connexin 30 (Cx30), one of the two connexins abundantly expressed by astrocytes, was recently shown to be a critical regulator of excitatory synaptic transmission by controlling the astroglial coverage of synapses. However, the role of Cx30 in the regulation of inhibitory synaptic transmission and excitatory/inhibitory balance remains elusive. Here, we investigated the role of astroglial Cx30 on the electrophysiological and morphological properties of five classes of hippocampal CA1 stratum oriens and pyramidale neurons, defined by the unsupervised Ward's clustering. Using Cx30 knockout mice, we found that Cx30 alters specific properties of some subsets of CA1 interneurons, such as resting membrane potential and sag ratio, while other parameters, such as action potential threshold and saturation frequency, were more frequently altered among the different classes of neurons. The excitation‐inhibition balance was also differentially and selectively modulated among the different neuron subtypes. Only slight morphological differences were observed on reconstructed neurons. Altogether, these data indicate that Cx30 differentially alters the electrophysiological and morphological properties of hippocampal cell populations, and modulates both their excitatory and inhibitory inputs. Astrocytes, via Cx30, are thus active modulators of both excitatory and inhibitory synapses in the hippocampus.