bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancing the Viscosity‐Sensitive Range of a BODIPY Molecular Rotor by Two Orders of Magnitude
Authors: Toliautas Stepas , Dodonova Jelena , Žvirblis Audrius , Čiplys Ignas , Polita Artūras , Devižis Andrius , Tumkevičius Sigitas , Šulskus Juozas , Vyšniauskas Aurimas 
Published: April 2019

AbstractMolecular rotors are a class of fluorophores that enable convenient imaging of viscosity inside microscopic samples such as lipid vesicles or live cells. Currently, rotor compounds containing a boron‐dipyrromethene (BODIPY) group are among the most promising viscosity probes. In this work, it is reported that by adding heavy‐electron‐withdrawing −NO2 groups, the viscosity‐sensitive range of a BODIPY probe is drastically expanded from 5–1500 cP to 0.5–50 000 cP. The improved range makes it, to our knowledge, the first hydrophobic molecular rotor applicable not only at moderate viscosities but also for viscosity measurements in highly viscous samples. Furthermore, the photophysical mechanism of the BODIPY molecular rotors under study has been determined by performing quantum chemical calculations and transient absorption experiments. This mechanism demonstrates how BODIPY molecular rotors work in general, why the −NO2 group causes such an improvement, and why BODIPY molecular rotors suffer from undesirable sensitivity to temperature. Overall, besides reporting a viscosity probe with remarkable properties, the results obtained expand the general understanding of molecular rotors and show a way to use the knowledge of their molecular action mechanism for augmenting their viscosity‐sensing properties.
Modelling the Inhibition of Selenoproteins by Small Molecules Using Cysteine and Selenocysteine Derivatives
Authors: Reddy Kishorkumar M. , Mugesh Govindasamy 
Published: April 2019

AbstractSmall molecule‐based electrophilic compounds such as 1‐chloro‐2,4‐dinitrobenzene (CDNB) and 1‐chloro‐4‐nitrobenzene (CNB) are currently being used as inhibitors of cysteine‐ and selenocysteine‐containing proteins. CDNB has been used extensively to determine the activity of glutathione S‐transferase and to deplete glutathione (GSH) in mammalian cells. Also, CDNB has been shown to irreversibly inhibit thioredoxin reductase (TrxR), a selenoenzyme that catalyses the reduction of thioredoxin (Trx). Mammalian TrxR has a C‐terminal active site motif, Gly‐Cys‐Sec‐Gly, and both the cysteine and selenocysteine residues could be the targets of the electrophilic reagents. In this paper we report on the stability of a series of cysteine and selenocysteine derivatives that can be considered as models for the selenoenzyme–inhibitor complexes. We show that these derivatives react with H2O2 to generate the corresponding selenoxides, which undergo spontaneous elimination to produce dehydroalanine. In contrast, the cysteine derivatives are stable towards such elimination reactions. We also demonstrate, for the first time, that the arylselenium species eliminated from the selenocysteine derivatives exhibit significant redox activity by catalysing the reduction of H2O2 in the presence of GSH (GPx (glutathione peroxidase)‐like activity), which suggests that such redox modulatory activity of selenium compounds may have a significant effect on the cellular redox state during the inhibition of selenoproteins.
Surface‐Confined SnS2@C@rGO as High‐Performance Anode Materials for Sodium‐ and Potassium‐Ion Batteries
Authors: Li Deping , Sun Qing , Zhang Yamin , Chen Lina , Wang Zhongpu , Liang Zhen , Si Pengchao , Ci Lijie 
Published: April 2019

AbstractPotassium‐ (PIBs) and sodium‐ion batteries (SIBs) are emerging as promising alternatives to lithium‐ion batteries owing to the low cost and abundance of K and Na resources. However, the large radius of K+ and Na+ lead to sluggish kinetics and relatively large volume variations. Herein, a surface‐confined strategy is developed to restrain SnS2 in self‐generated hierarchically porous carbon networks with an in situ reduced graphene oxide (rGO) shell (SnS2@C@rGO). The as‐prepared SnS2@C@rGO electrode delivers high reversible capacity (721.9 mAh g−1 at 0.05 A g−1) and superior rate capability (397.4 mAh g−1 at 2.0 A g−1) as the anode material of SIB. Furthermore, a reversible capacity of 499.4 mAh g−1 (0.05 A g−1) and a cycling stability with 298.1 mAh g−1 after 500 cycles at a current density of 0.5 A g−1 were achieved in PIBs, surpassing most of the reported non‐carbonaceous anode materials. Additionally, the electrochemical reactions between SnS2 and K+ were investigated and elucidated.
Preface to Special Issue of ChemSusChem—Water Splitting: From Theory to Practice
Authors: Tilley S. David , Selloni Annabella , Hisatomi Takashi 
Published: April 2019

AbstractIn this Editorial, Guest Editors David Tilley, Annabella Selloni, and Takashi Hisatomi introduce the Special Issue of ChemSusChem on Water Splitting: From Theory to Practice. The significance and enormous challenges of sunlight‐driven water splitting are reviewed and the contents of the contributions to the Special Issue are outlined.
Mobile target tracking algorithm for wireless camera sensor networks with adjustable monitoring direction of nodes
Authors: Lu Xu , Zhang Yujing , Liu Jun , Yuan Fei , Cheng Lianglun 
Published: April 2019

SummaryWireless camera sensor networks (WCSNs) possess a powerful physical environment monitoring capability. Camera nodes with adjustable monitoring directions further improve their flexibility. This study focuses on tracking multiple mobile targets to investigate the node scheduling and target location evaluation strategy of WCSNs on the basis of rotating nodes. By referring to existing research, this study improves the camera node monitoring and rotation model and proposes three network performance evaluation indicators. The proposed algorithm schedules nodes and their monitoring directions by using the unutilized energy of the nodes and the number of monitored targets. It also predicts the moving trends of the targets and selects active nodes by using the locations and linear speeds of the targets. Experimental results show that the proposed algorithm has a high target tracking accuracy. Compared with traditional target tracking algorithms, the proposed algorithm can effectively reduce the number of active nodes, balance the energy consumption between nodes, and prolong network lifetime.
Intelligent Information‐Centric Networking routing scheme under imprecise information
Authors: Zhang Lingling , Lv Jianhui 
Published: April 2019

SummaryInformation‐Centric Networking (ICN) has been accepted to overcome some weaknesses of the current Internet architecture, showing that “what is being exchanged” is more important than “who are exchanging information.” Given the inadequate considerations on Quality of Service (QoS) and energy saving in ICN routing, we propose in this paper a routing algorithm to enhance the two aspects. At first, on one hand, Cauchy distribution is used as a fuzzy model to evaluate users' QoS requirements, such as bandwidth, delay, and error rate; on the other hand, we formulate energy saving problem to evaluate the green quality of routing algorithm. Then, we design a link selection approach by considering QoS and energy saving, which belongs to a multi‐objective decision problem resolved by intelligent drops algorithm. Finally, we implement the proposed algorithm and compare it with the famous adaptive forwarding mechanism in terms of some significant metrics, and the experimental results reveal that the proposed algorithm is more efficient.
Optimal barrier coverage for critical area surveillance using wireless sensor networks
Authors: Benahmed Tariq , Benahmed Khelifa 
Published: April 2019

SummaryIntrusion detection using barrier coverage is one of many applications existed in wireless sensor networks. The main purpose of using barrier coverage is to monitor the borders of a specific area against the intruders that are trying to penetrate this critical area by ensuring the total coverage with a low cost and extending the lifetime of the network, many solutions have been proposed in the literature in order to solve the coverage problem in wireless sensor networks, which became a vital field of research. In this paper, we present a new technique based on geometric mathematical models, in order to guarantee the total coverage of our deployed barriers with a minimum possible number of sensors. The idea is to calculate the number of sensors adequate to cover a barrier before deployment. We then formulate the problem to minimize the number of sensors to be deployed to properly cover a barrier; the calculation makes it possible to solve this problem in polynomial using our own heuristic. Additionally, we propose a new mechanism for ensuring a fault‐tolerant network by detecting the faulty sensors and select other suited sensors to close the existing gaps inside the barriers and detecting the sensors whose energy is low before the failure. The obtained simulation results prove the effectiveness of the proposed algorithms.
A virtualized infrastructure to offer network mapping functionality in SDN networks
Authors: Manzanares‐Lopez Pilar , Muñoz‐Gea Juan Pedro , Malgosa‐Sanahuja Josemaria , Flores‐de la Cruz Adrian 
Published: April 2019

SummaryThe separation of control and forwarding planes in software‐defined networking (SDN) networks is a key issue of the SDN technology. This feature and the existence of the SDN controller allow the developing of dynamic, adaptable and manageable networks, networks that require adequate services, and applications. However, the separation of these planes prevents the use of existing powerful tools that were coded considering traditional networks. In this paper, we make use of the potential of network virtualization (NV) technologies to propose the use of a virtualized infrastructure that makes possible the incorporation of these existing services and/or applications to an SDN network, without the need for programming additional and complex software modules in the SDN controller. Thus, in this paper, NV is not employed to develop a network managed by SDN but to broaden and give support to the SDN control layer. As an example, we describe the incorporation of nmap (a versatile and powerful tool widely used by security experts for network exploration) into the SDN framework. It is only necessary to develop a simple control plane service that thanks to the proposed virtualized infrastructure allows the inclusion of this powerful management application. The result offers the complete functionality of the nmap utility to the network administrators, who control the SDN network through the out‐of‐band control plane. In addition, a northbound REST API has been defined to offer the main functionality of the tool (host discovery, port scanning, and operating system detection) to the application layer.
An eigenvalue‐based edge infrastructure for cloud‐based CDN
Authors: Sahoo Sampa , Sahoo Bibhudatta , Turuk Ashok Kumar 
Published: April 2019

SummaryIn today's dynamic video landscape, an end user needs services to be delivered to any devices anytime with less delay over the Internet. Now users' expectation has changed; they want faster time‐to‐market, cost reduction, and the ability to adjust according to the evolving requirements, which are a limit for the traditional server‐based approach. The explosive growth of the internet multimedia application needs a new approach to content delivery to overcome the limitations of server‐based techniques. Cloud‐based content delivery networks (CCDNs) have recently started to emerge where contents are cached from the cloud storage and delivered through the distribution service to meet quality of services (QoS) of requested services. In this paper, we dealt with CCDN deployment problem and proposed a new eigenvalue‐based edge infrastructure for a network service provider to serve the users with a variation on proximity interest concerning operational cost and user QoS satisfaction. The edge infrastructure designing is a two‐step process: (a) ideal location search for placing edge server and (b) edge server placement and capacity provisioning. The performance of the proposed approach is appraised via modeling and simulation. Performance evaluation outcomes are exhibited to manifest the effectiveness and competitiveness of our approach when compared with existing algorithms.
Adaptable mesocosm facility to study oil spill impacts on corals
Authors: Silva Denise P. , Duarte Gustavo , Villela Helena D.M. , Santos Henrique F. , Rosado Phillipe M. , Rosado João Gabriel , Rosado Alexandre S. , Ferreira Edir M. , Soriano Adriana U. , Peixoto Raquel S. 
Published: April 2019

AbstractAlthough numerous studies have been carried out on the impacts of oil spills on coral physiology, most have relied on laboratory assays. This scarcity is partly explained by the difficulty of reproducing realistic conditions in a laboratory setting or of performing experiments with toxic compounds in the field. Mesocosm systems provide the opportunity to carry out such studies with safe handling of contaminants while reproducing natural conditions required by living organisms. The mesocosm design is crucial and can lead to the development of innovative technologies to mitigate environmental impacts. Therefore, this study aimed to develop a mesocosm system for studies simulating oil spills with several key advantages, including true replication and the use of gravity to control flow‐through that reduces reliance on pumps that can clog thereby decreasing errors and costs. This adaptable system can be configured to (a) have continuous flow‐through; (b) operate as an open or closed system; (c) be fed by gravity; (d) have separate mesocosm sections that can be used for individual and simultaneous experiments; and (e) simulate the migration of oil from ocean oil spills to the nearby reefs. The mesocosm performance was assessed with two experiments using the hydrocoral Millepora alcicornis and different configurations to simulate two magnitudes of oil spills. With few exceptions, physical and chemical parameters remained stable within replicates and within treatments throughout the experiments. Physical and chemical parameters that expressed change during the experiment were still within the range of natural conditions observed in Brazilian marine environments. The photosynthetic potential (Fv/Fm) of the algae associated with M. alcicornis decreased in response to an 1% crude‐oil contamination, suggesting a successful delivery of the toxic contaminant to the targeted replicates. This mesocosm is customizable and adjustable for several types of experiments and proved to be effective for studies of oil spills.
A meta‐analysis of herbivore effects on plant attractiveness to pollinators
Authors: Moreira Xoaquín , Castagneyrol Bastien , Abdala‐Roberts Luis , Traveset Anna 
Published: April 2019

AbstractHerbivores may directly or indirectly affect plant attractiveness to pollinators. Although several studies have reported on these effects, there is yet no general consensus on the strength and sign of such interactions or their contingency on herbivory features such as the plant tissue attacked. We performed a meta‐analysis of studies testing for effects of herbivores on floral traits, plant attractiveness to pollinators, and plant reproductive success. We also assessed whether herbivore effects depended on the plant tissue attacked by herbivores and if real or simulated herbivory was used. We found an overall significant negative effect of herbivores on floral traits, plant attractiveness to pollinators, and plant reproductive success. These effects were, however, contingent on the plant tissue attacked and on whether real or simulated damage was used. Real floral and leaf, but not root, herbivores showed detrimental effects on floral traits and plant attractiveness to pollinators. In addition, real leaf, but not floral or root herbivory, lowered plant reproductive success. Contrastingly, simulated leaf and floral herbivory showed no effect on any of the response variables. These findings help move forward our understanding of the strength and directionality of herbivore effects on plant attractiveness to pollinators and their underlying mechanisms.
Evaluation of bias on the probability of collapse from amplitude scaling using spectral‐shape‐matched records
Authors: Dávalos Héctor , Miranda Eduardo 
Published: April 2019

SummaryAlthough for many years it was thought that amplitude scaling of acceleration time series to reach a target intensity did not introduce any bias in the results of nonlinear response history analyses, recent studies have showed that scaling can lead to an overestimation of deformation demands with increasing scale factors. Some studies have suggested that the bias can be explained by differences in spectral shape between the response spectra of unscaled and scaled records. On the basis of these studies, some record selection procedures assume that if records are selected using spectral‐shape‐matching procedures, amplitude scaling does not induce any bias on the structural response. This study evaluates if bias is introduced on lateral displacement demands and seismic collapse risk estimates even when spectral shape is carefully taken into consideration when selecting ground motions. Several single‐degree‐of‐freedom and multiple‐degree‐of‐freedom systems are analyzed when subjected to unscaled and scaled ground motions selected to approximately match the mean and the variance of the conditional spectrum at the target level of intensity. Results show that an explicit consideration of spectral shape is not enough to avoid a systematic overestimation of lateral displacement demands and collapse probabilities as the scale factor increases. Moreover, the bias is observed in practically all cases for systems with strength degradation and it increases with decreasing period and decreasing lateral strength relative to the strength required to remain elastic. Key reasons behind the bias are presented by evaluating input energy, causal parameters, and damaging pulse distributions in unscaled and scaled ground motion sets.
A Re-Evaluation of Chironomid Deformities as an Environmental Stress Response: Avoiding Survivorship Bias and Testing Noncontaminant Biological Factors
Authors: Gagliardi Bryant , Long Sara M. , Pettigrove Vincent J. , Griffin Philippa C. , Hoffmann Ary A. 
Published: April 2019

Abstract
Larval deformities have been observed in chironomids, and are thought to be associated with aquatic contaminant exposure. However, in laboratory assays, deformities have not been linked with contaminants in the absence of potential confounding variables including mortality, which introduces a survivorship bias. There is also a paucity of data on noncontaminant causes. In addition, power analyses are rarely undertaken, meaning that effect sizes detectable are usually uncertain. We therefore aimed to clarify factors associated with deformities, by running survivorship bias–free (i.e., sublethal) assays, assessing contaminant (copper and imidacloprid) and noncontaminant (malnutrition) stressors, and considering natural biological (metamorphosis) factors in Chironomus tepperi. We included a posteriori power analyses for all tests. Our assays found no significant association between tested factors and deformity rate. Power analyses indicated that the stressor experiment had moderate power to detect deformity effects. The metamorphosis assay had relatively lower power (due to an unexpectedly high control deformity rate), highlighting the importance of power tests in these types of evaluations. These results, in conjunction with others recently published, raise doubts as to the causal effects of environmental stressors on deformity incidence. By avoiding survivorship bias, and by testing noncontaminant factors and statistical power, we present a more holistic methodology, to resolve ongoing uncertainty in this area. We also discuss possible future directions for chironomid deformity research, and concerns regarding survivorship bias in ecotoxicology. Environ Toxicol Chem 2019;38:1658–1667. © 2019 SETAC
Empathetic Practice: The Struggle and Virtue of Empathizing with a Patient's Suffering
Authors: Campelia Georgina , Tate Tyler 
Published: April 2019

AbstractIn this article, our analysis of empathy in the clinical context hinges on the complexities of patients who are acutely suffering. Using a case concerning a heart transplant patient with Duchenne muscular dystrophy, Alex, and his nurse, Joe, we investigate how empathy’s phenomenological nebulousness can generate doubts about its virtue. Even when asking, “How are you, Alex?” Joe hates the question; it seems empty, silly. Cases like this show both that the enactment of empathy is sometimes challenging and that it can be reasonable to wonder if empathy is a virtue at all. Perhaps Alex’s suffering is simply too massive: Joe cannot possibly know how he feels, so why try? Perhaps empathy would only cause Joe to suffer along with Alex. Not only is empathy difficult to produce in the context of Alex’s suffering; it may not even be possible; and if we simply cannot muster empathy, what is the point of morally demanding it?In response, we distinguish different kinds of empathic engagements from one another and offer separate counsel. We argue that it is important to understand empathy as something that must be honed across varied contexts before it can be called a virtue. Conceptualizing and operationalizing empathy in this way helps to ground its possibility and virtue even in the most challenging and complex clinical encounters.
The Critical Role of Medical Institutions in Expanding Access to Investigational Interventions
Authors: Spector‐Bagdady Kayte , Weatherwax Kevin J. , Gravelin Misty , Shuman Andrew G. 
Published: April 2019

AbstractThe U.S. federal government provides two tracks for eligible patients to obtain access outside clinical trials to investigational interventions currently under study for potential clinical benefits: the Food and Drug Administration’s expanded access pathway and the pathway created by the more recent Right to Try Act. In this issue of the Hastings Center Report, with a critical focus on patients, industry, and the research enterprise, Kelly Folkers and colleagues frame the inherent challenges that these pathways are meant to solve and have also inadvertently created. But an additional key focus is how the relevant situations should be managed at the bedside and how the system risks both inefficient and inequitable access to options at the institutional level. Although either pathway could be helpful to patients, the challenges of having the pathways coexist are greater than the sum of their parts. Individual clinicians represent the front line of the regulatory and eligibility challenges of expanded access and right to try, making clinical education a critical component of a comprehensive approach to using them well. But it is medical institutions that must take the lead on supporting access to investigational options in the most equitable and effective manner possible.