bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intrinsically Photoswitchable α/β Peptides toward Two‐State Foldamers
Authors: Marafon Giulia , Crisma Marco , Moretto Alessandro 
Published: June 2018

AbstractA simple, unsaturated, E–Z photoisomerizable β‐amino acid, (Z)‐3‐aminoprop‐2‐enoic acid, has been introduced into peptide foldamers through a one‐pot chemical coupling, based on Pd/Cu‐catalyzed olefin oxidative amidation, between two peptide segments carrying, respectively, a ‐Gly‐NH2 residue at the C‐terminus and an acryloyl group at the N‐terminus. Reversible conversion between the Z and E configurations of the 3‐aminoprop‐2‐enoic linkage was achieved photochemically. A crystallographic analysis on two model compounds shed light on the consequences, in terms of 3D structure and self‐association properties, brought about by the different configuration of the unsaturated linkage. As a proof of concept, E–Z photoisomerization of a 3‐aminoprop‐2‐enoic acid residue, inserted as the junction between two conformationally distinct peptide domains (one helical while the other β‐sheet promoter), allowed supramolecular self‐association to be reversibly turned on/off.
Tunable Chiroptical Properties from the Plasmonic Band to Metal–Ligand Charge Transfer Band of Cysteine‐Capped Molybdenum Oxide Nanoparticles
Authors: Li Yiwen , Cheng Jiaji , Li Jiagen , Zhu Xi , He Tingchao , Chen Rui , Tang Zikang 
Published: June 2018

AbstractUnderstanding the interactions between a semiconducting nanocrystal surface and chiral anchoring molecules could resolve the mechanism of chirality induction in nanoscale and facilitate the rational design of chiral semiconducting materials for chiroptics. Now, chiral molybdenum oxide nanoparticles are presented in which chirality is transferred via a bio‐to‐nano approach. With facile control of the amount of chiral cysteine molecules under redox treatment, circular dichroism (CD) signals are generated in the plasmon region and metal–ligand charge‐transfer band. The obtained enhanced CD signals with tunable lineshapes illustrate the possibility of using chiral molybdenum oxide nanoparticles as potentials for chiral semiconductor nanosensors, optoelectronics, and photocatalysts.
Ring‐Opening Metathesis Polymerization in Aqueous Media Using a Macroinitiator Approach
Authors: Foster Jeffrey C. , Varlas Spyridon , Blackman Lewis D. , Arkinstall Lucy A. , O'Reilly Rachel K. 
Published: June 2018

AbstractWater‐soluble and amphiphilic polymers are of great interest to industry and academia, as they can be used in applications such as biomaterials and drug delivery. Whilst ring‐opening metathesis polymerization (ROMP) is a fast and functional group tolerant methodology for the synthesis of a wide range of polymers, its full potential for the synthesis of water‐soluble polymers has yet to be realized. To address this, we report a general strategy for the synthesis of block copolymers in aqueous milieu using a commercially available ROMP catalyst and a macroinitiator approach. This allows for excellent control in the preparation of block copolymers in water. If the second monomer is chosen such that it forms a water‐insoluble polymer, polymerization‐induced self‐assembly (PISA) occurs and a variety of self‐assembled nano‐object morphologies can be accessed.
Experimental studies on drag reduction by coupled addition of nonionic polymer poly(ethylene oxide) and cationic surfactant cetyltrimethyl ammonium chloride
Authors: Pang Mingjun , Xie Chengcheng , Zhang Zhan , Dai Junrong 
Published: June 2018

AbstractMore and more attention is paid to the synergistic drag reduction by polymers and surfactants because there are serious disadvantages of the drag reduction by them alone. In order to understand the synergistic effect of the drag reduction by polymers and surfactants, in‐depth investigations are performed on the drag reduction behavior by simultaneous addition of nonionic polymer poly(ethylene oxide) (PEO) and cationic surfactant cetyltrimethyl ammonium chloride (CTAC) in a two‐dimensional channel flow. The sodium salicylate (NaSal) is added to provide counter ions for promoting micelle formation. For comparisons, the drag‐reducing behaviors of PEO and CTAC/NaSal alone are also investigated. The present results show that the synergistic effect of the drag reduction depends upon concentration combination of PEO and CTAC/NaSal. The Reynolds number range with a high drag‐reducing rate becomes wider due to the simultaneous addition of PEO & CTAC/NaSal, whereas the ultimate drag reduction rate has a minimal change. The drag reduction enhancement is a complicated and nonlinear issue, and it seems that PEO and CTAC/NaSal play different roles in the drag reduction in different Reynolds number ranges.
Characterization of polymorphic microsatellite loci for North American common greenbrier, Smilax rotundifolia (Smilacaceae)
Authors: Wang Ruihong , Li Mengdi , Wu Xue , Shen Chao , Yu Wendi , Liu Jinliang , Qi Zhechen , Li Pan 
Published: June 2018

Premise of the StudyMicrosatellite markers were developed for Smilax rotundifolia (Smilacaceae), an understory vine widely distributed in eastern North America, to investigate genetic diversity and structure. Cross‐amplification was tested in three congeneric species: S. china, S. riparia, and S. walteri.Methods and ResultsA total of 6153 simple sequence repeat primer pairs were detected from the de novo–assembled transcriptome data (88,3962 contigs) of S. rotundifolia. Thirty‐three polymorphic microsatellite loci were selected for further analysis among 96 individuals representing four natural populations of the species. The number of alleles ranged from two to 15, and 87.9% of the developed primer pairs could be cross‐amplified in at least one of three congeneric Smilax species.ConclusionsThe simple sequence repeat markers developed in this study will facilitate further studies on genetic diversity and phylogeographic patterns of S. rotundifolia and provide additional potential microsatellite resources for other Smilax species.
The park never born: Outcome of a quarter of a century of inaction on the sea‐floor integrity of a proposed but not established Marine Protected Area
Authors: Bianchi Carlo Nike , Cocito Silvia , Diviacco Giovanni , Dondi Nicolò , Fratangeli Francesca , Montefalcone Monica , Parravicini Valeriano , Rovere Alessio , Sgorbini Sergio , Vacchi Matteo , Morri Carla 
Published: June 2018

Abstract

Marine Protected Areas (MPAs) are a major tool to conserve marine ecosystems but are also strongly attractive to tourists, the increased numbers of which can cause environmental issues if not properly managed.
Proposing an MPA and then failing to establish it risks advertising the beauty of a marine area without managing the unavoidable increase in tourism. This is what happened at Gallinara Island (Ligurian Sea, north‐western Mediterranean), where an MPA was proposed in 1990 but has not yet been established.
Benthic data collected soon after the proposal (1990–92) have been compared with similar information obtained in subsequent periods (2009 and 2016): change has been assessed both visually and statistically, using multivariate and univariate techniques.
The Gallinara sea floor supported five epibenthic communities in 1991, four of which corresponded to European Nature Information System (EUNIS) habitats; the fifth epibenthic community, characterized by the erect sponge Axinella polypoides, should be included in the next revision of EUNIS.
In the 25 years since the original MPA proposal, all epibenthic communities have exhibited a reduction in their three‐dimensional structure and biotic homogenization, and severe decreases in species diversity, and the sea floor has been littered with derelict fishing gear and other waste from boats.
In absence of the MPA, proposals to develop a management plan for a marine Site of Community Importance (SCI) have been provided, to reduce sea‐based human pressures. The dramatic alteration of Gallinara sea floor after 25 years of negligence and inaction is a sad warning for other unmanaged yet beautiful natural areas within urbanized regions of the world.
Penalized spline smoothing using Kaplan–Meier weights with censored data
Authors: Orbe Jesus , Virto Jorge 
Published: June 2018

AbstractIn this paper, we consider the problem of nonparametric curve fitting in the specific context of censored data. We propose an extension of the penalized splines approach using Kaplan–Meier weights to take into account the effect of censorship and generalized cross‐validation techniques to choose the smoothing parameter adapted to the case of censored samples. Using various simulation studies, we analyze the effectiveness of the censored penalized splines method proposed and show that the performance is quite satisfactory. We have extended this proposal to a generalized additive models (GAM) framework introducing a correction of the censorship effect, thus enabling more complex models to be estimated immediately. A real dataset from Stanford Heart Transplant data is also used to illustrate the methodology proposed, which is shown to be a good alternative when the probability distribution for the response variable and the functional form are not known in censored regression models.
Silver‐doped graphite carbon nitride nanosheets as fluorescent probe for the detection of curcumin
Authors: Yang Haifen , Li Xuebing , Wang Xinxv , Chen Wenfang , Bian Wei , Choi Martin M. F. 
Published: June 2018

AbstractGreen fluorescent silver (Ag)‐doped graphite carbon nitride (Ag‐g‐C3N4) nanosheets have been fabricated by an ultrasonic exfoliating method. The fluorescence of the Ag‐g‐C3N4 nanosheets is quenched by curcumin. The fluorescence intensity decreases with the increase in the concentration of curcumin, indicating that the Ag‐g‐C3N4 nanosheets can function as a non‐toxic and facile fluorescence probe to detect curcumin. The fluorescence intensity of Ag‐g‐C3N4 nanosheets shows a linear relationship to curcumin in the concentration range 0.01–2.00 μM with a low detection limit of 38 nM. The fluorescence quenching process between curcumin and Ag‐g‐C3N4 nanosheets mainly is based on static quenching. The fluorescent probe has been successfully applied to analyse curcumin in human urine and serum samples with satisfactory results.
Making image and vision effortless: Learning methodology through the quick and easy design of short case studies
Authors: Mateo Sanguino Tomás de J. , Castilla Webber Pedro A. 
Published: June 2018

AbstractLearning on machine vision and image processing generally require high‐level knowledge on techniques, algorithms and programming skills. The educational process is frequently supported by formal lecture approaches assisted by object lessons or lab activities, and project‐based learning methodologies where students engage complex questions, challenges, and problems over a longer period of time. These educational approaches are not effective when applying to learners in robotics study programs or without a programming background where time and motivation are different. To address this concern, this paper presents an educational tool developed to teach the basic principles of machine vision and image processing through the design of short case studies. As the main contribution, the proposed tool allows to shorten the training time required by students—mainly beginners—without the skills in programming and deep understanding of math hidden behind each image operation. This lets to fit theoretical and practical works into short development times. To this end, we conducted an educational experience in robotics subjects with third year students of the computer science and industrial engineering degrees. As a result of this scenario, we statistically compared the teaching and learning issues, the user preferences about the tool and the student academic performance.
Photocontrol of Drug Release from Supramolecular Hydrogels with Green Light
Authors: Karcher Johannes , Pianowski Zbigniew L. 
Published: June 2018

AbstractPhotoresponsive smart materials transform light energy into sophisticated functions. They find increasing biomedical applications in light‐induced drug‐release and photopharmacology, because they can provide the desired therapeutic effect locally due to precise spatiotemporal dosage control. However, the majority of reported studies rely on cytotoxic UV light that penetrates tissues poorly. Here, we report the first drug‐releasing system based on photochromic low molecular weight supramolecular hydrogels that is triggered with visible light. We demonstrated green‐light‐induced release of structurally unmodified antibiotic, anticancer, and anti‐inflammatory drugs under physiological conditions. Using the antibiotic‐loaded gel, we selectively inhibited bacterial growth with green light.
A Short Discussion about Practices in the Calculation of Particle Size Distribution by Using the Concept of Moments
Authors: Zhang Qian 
Published: June 2018

AbstractDie theoretische Beschreibung einer Partikelgrößenverteilung als stetige, differenzierbare Funktion bietet den Vorteil einer schlichten Formulierung ohne Verlust von mathematischer Korrektheit. Da es aber bei realen Mengenverteilungen immer nur endliche Mengen und bei deren Messungen immer eine endliche Anzahl an Größenintervallen gibt, sind messtechnisch ermittelte Partikelgrößenverteilungen immer diskrete Verteilungen, und die Verteilungsfunktionen sind nicht differenzierbar. Für die Auswertung und Darstellung der Verteilungen werden Annahmen getroffen, die bei weitergehenden Auswertungen nicht immer berücksichtigt werden. In diesem Beitrag wird die gängige Praxis bei der Umrechnung von Partikelgrößenverteilungen mit dem Konzept von Momenten diskutiert und numerische Differenzen zwischen verschiedenen Rechenmethoden aufgezeigt.
FRFB: Top‐k Followee Recommendation by exploring the Following Behaviors in social networks
Authors: Xue Zhengyuan , Li Ruixuan , Li Yuhua , Huo Lin , Gu Xiwu , Xiao Weijun 
Published: June 2018

SummaryAs social networks such as micro‐blogging sites rapidly grow, deciding whom to follow (followee recommendation) becomes a significantly important problem. Most existing works exclusively rely on two traditional factors: the proximity between two users in the network topology or the similarity of the user‐generated contents in the social network, disregarding the effect of users' following behaviors. The challenge of how to effectively combine these two factors remains largely open. Moreover, most research studies simply sort the scores to find top‐k users, which is time‐consuming, especially for large‐scale networks. In this paper, we propose the idea that “predict users' following behaviors by following behaviors themselves.” We consider a user's following to others as a normal process of dynamic and coherent behavior, and we model the potential propagation of the users' following behaviors. Furthermore, based on our previous research on top‐k selection problem, we propose an effective top‐k followee recommendation algorithm, called FRFB. FRFB has low complexity and high scalability and, moreover, good adaptability to real‐life dynamic social networks. We conduct extensive experiments, with two real social network data sets (Wiki and Twitter), which show that FRFB outperforms the well‐known topology‐based followee recommendation algorithms.
Pt and Pt–Ni(OH)2 Electrodes for the Hydrogen Evolution Reaction in Alkaline Electrolytes and Their Nanoscaled Electrocatalysts
Authors: Ruqia Bibi , Choi Sang‐Il 
Published: June 2018

AbstractThe design and synthesis of Pt‐based electrocatalysts for the hydrogen evolution reaction (HER) are of great importance for the successful development of hydrogen‐based alternative energy technologies. Although Pt is considered to be the most active catalyst for the HER, its reaction performance is limited in alkaline solutions owing to a slow rate for water dissociation. Therefore, many research groups have intensively investigated reaction mechanisms and developed system designs and efficient Pt‐based catalysts to enhance the alkaline HER. Herein, we summarize the catalytic surface specificity of Pt and Pt–Ni(OH)2 materials to control the kinetics of the alkaline HER. In particular, we increase our understanding of Ni(OH)2‐modified Pt surfaces and the corresponding nanoscaled Pt–Ni(OH)2 electrocatalysts to improve the sluggish water‐dissociation step, and this knowledge will guide us to future sustainable energy applications of advanced nanomaterials.
Ion‐Selective Prussian‐Blue‐Modified Celgard Separator for High‐Performance Lithium–Sulfur Battery
Authors: Wu Xian , Fan Lishuang , Qiu Yue , Wang Maoxu , Cheng Junhan , Guan Bin , Guo Zhikun , Zhang Naiqing , Sun Kening 
Published: June 2018

AbstractApplication of Li–S batteries has been restricted because of their major problem, that is, shuttling of soluble polysulfides between electrodes, which results in serious capacity fading. For the development of high‐performance Li–S batteries, we first time utilize a simple growth method to introduce a Prussian blue (PB)‐modified Celgard separator as an ion‐selective membrane. The unique structure of PB could effectively suppress the shuttle of polysulfides but scarcely affect the transfer ability of lithium ions, which is beneficial to achieve high sulfur conversion efficiency and capacity retention. The Li–S battery with PB‐modified Celgard separator has an average capacity decay of only 0.03 % per cycle at 1 C after 1000 cycles.
Efficiently enforcing artisanal fisheries to protect estuarine biodiversity
Authors: Duarte de Paula Costa Micheli , Mills Morena , Richardson Anthony J. , Fuller Richard A. , Muelbert José H. , Possingham Hugh P. 
Published: June 2018

AbstractArtisanal fisheries support millions of livelihoods worldwide, yet ineffective enforcement can allow for continued environmental degradation due to overexploitation. Here, we use spatial planning to design an enforcement strategy for a pre‐existing spatial closure for artisanal fisheries considering climate variability, existing seasonal fishing closures, representative conservation targets and enforcement costs. We calculated enforcement cost in three ways, based on different assumptions about who could be responsible for monitoring the fishery. We applied this approach in the Patos Lagoon estuary (Brazil), where we found three important results. First, spatial priorities for enforcement were similar under different climate scenarios. Second, we found that the cost and percentage of area enforced varied among scenarios tested by the conservation planning analysis, with only a modest increase in budget needed to incorporate climate variability. Third, we found that spatial priorities for enforcement depend on whether enforcement is carried out by a central authority or by the community itself. Here, we demonstrated a method that can be used to efficiently design enforcement plans, resulting in the conservation of biodiversity and estuarine resources. Also, cost of enforcement can be potentially reduced when fishers are empowered to enforce management within their fishing grounds.
Inter‐ and intraspecific variation in mangrove carbon fraction and wood specific gravity in Gazi Bay, Kenya
Authors: Gillerot Loïc , Vlaminck Ellen , De Ryck Dennis J. R. , Mwasaru Donald Maringa , Beeckman Hans , Koedam Nico 
Published: June 2018

AbstractThe tropical mangrove ecosystem harbors great potential for carbon offsetting schemes because of their exceptionally high carbon sequestration potential. These cannot only generate an income for local communities by financially compensating for the non‐exploitation of protected or replanted stands, but also simultaneously reduce emissions due to forest degradation and deforestation, thereby helping to counteract the global threat on these forests. As carbon is directly monetized through offsetting carbon emissions, accurate species‐specific estimation of carbon content in trees is essential and reduces the propagation of errors generated by accounting uncertainties. Accordingly, this study assessed variation in both carbon fraction and wood specific gravity among and within the 10 mangrove species occurring in Gazi Bay, Kenya. Significant interspecific differences were found with values ranging from 45.8% (Avicennia marina) to 49.8% (Ceriops tagal) for carbon fraction and from 0.58 (Sonneratia alba) to 0.93 (Pemphis acidula) for wood specific gravity. The influence of environmental factors (soil salinity, stand density, and elevation a.s.l. as a proxy for multiple interrelated conditions) was investigated, but only elevation a.s.l. appeared to have a species‐specific though moderate influence only on carbon fraction. Significant differences in carbon fraction and wood specific gravity were found between stem, aerial roots, and branches of Rhizophora mucronata. In contrast, no significant differences in carbon fraction were found among different stem tissues of A. marina, C. tagal and R. mucronata, the Bay's most abundant species. These results provide insight in carbon content variation, confirming the importance of considering species‐specific or even site‐specific values of carbon fraction and wood specific gravity, thereby rendering future carbon accounting more accurate.
Quantifying snow controls on vegetation greenness
Authors: Pedersen Stine Højlund , Liston Glen E. , Tamstorf Mikkel P. , Abermann Jakob , Lund Magnus , Schmidt Niels Martin 
Published: June 2018

AbstractSnow is a key driver for biotic processes in Arctic ecosystems. Yet, quantifying relationships between snow metrics and biological components is challenging due to lack of temporally and spatially distributed observations at ecologically relevant scales and resolutions. In this study, we quantified relationships between snow, air temperature, and vegetation greenness (using annual maximum normalized difference vegetation index [MaxNDVI] and its timing [MaxNDVI_DOY]) from ground‐based and remote‐sensing observations, in combination with physically based models, across a heterogeneous landscape in a high‐Arctic, northeast Greenland region. Across the 98‐km distance from the Greenland Ice Sheet (GrIS) to the coast, we quantified significant inland–coast gradients of air temperature, winter precipitation (using pre‐melt snow‐water‐equivalent [SWE]), and snowmelt timing (using snow‐free day of year [SnowFree_DOY]). Near the coast, the mean annual air temperature was 4.5°C lower, the mean SWE was 0.3 m greater, and the mean SnowFree_DOY was 37 d later, than near the GrIS. The regional continentality gradient was eight times stronger than the south‐to‐north air–temperature gradient along the Greenland east coast. Across this strong gradient, the mean vegetation greening‐up period (SnowFree_DOY‐MaxNDVI_DOY) varied spatially by 24–57 d. We quantified significant non‐linear relationships between the vegetation characteristics of MaxNDVI and MaxNDVI_DOY, and SWE, SnowFree_DOY, and growing degree‐days‐sums during greening‐up (Greening_GDD) across the 16‐yr study period (2000–2015). These demonstrated that the snow metrics, both SWE and SnowFree_DOY, were more important drivers of MaxNDVI and MaxNDVI_DOY than Greening_GDD within this seasonally snow‐covered region. The methodologies that provided temporally and spatially distributed snow, air temperature, and vegetation greenness data are applicable to any snow‐ and vegetation‐covered area on Earth.