bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hierarchical, multi‐grain rendezvous site selection by wolves in southern Italy
Authors: Ciucci Paolo , Boitani Luigi , Falco Matteo , Maiorano Luigi 
Published: February 2018

ABSTRACTFine‐scale knowledge of how anthropogenic effects may alter habitat selection by wolves (Canis lupus) is important to inform conservation management, especially where wolf populations are expanding into more populated areas or where human activity and development are increasingly encroaching on formerly pristine environments. From 1999 to 2003, we documented rendezvous sites (n = 31) used by wolves (n = 6 packs) in a previously unstudied wolf population in the southern Apennines, Italy (Pollino National Park [PNP]), where conditions are ideal to unveil behavioral adaptations of wolves living in human‐dominated landscapes. We adopted a hierarchical, multi‐scale habitat selection approach by using a set of environmental, topographic, and anthropogenic factors within multi‐grain resource selection functions (MRSFs) at the landscape and the territory extent. Habitat selection by wolves was scale‐dependent and different habitat components affected wolves at different grains. When establishing a territory at the landscape scale, wolves avoided areas featuring high densities of humans, paved roads, and trails, and they preferentially located territories where higher forest cover and rough terrain enhanced concealment and ensured reduced accessibility by humans. Concurrently, wolves also selected open areas and, at coarse grain, areas of high density of dirt roads and trails to enhance hunting and traveling efficiency. When selecting rendezvous sites within territories, wolves still selected for forest cover and lessened avoidance of anthropogenic features apparent at the lower order of selection. When choosing rendezvous sites, wolves also avoided low‐use anthropogenic linear features and rough terrain, unveiling trade‐offs in selection decisions across different spatial and temporal scales. Our results reinforce the notion that occurrence of wolves in human‐modified landscapes is shaped by avoidance of anthropogenic pressure, but they also indicate that rendezvous site selection by wolves conform to a hierarchical decision‐making process that is extent‐ and grain‐dependent. Spatially explicit models of rendezvous site selection such as the one we developed for PNP enhance management effectiveness for strategies such as regulating human access and activity during the pup rearing seasons, preventing human persecution, mitigating livestock depredations, and designing cost‐effective monitoring programs. © 2018 The Wildlife Society.
Manioc losses by terrestrial vertebrates in western Brazilian Amazonia
Authors: Abrahams Mark I. , Peres Carlos A. , Costa Hugo C. M. 
Published: February 2018

ABSTRACTTropical biodiversity benefits humanity. However, the costs of conserving topical biodiversity are largely borne by local communities. The damage caused by wild animals to human‐cultivated plants (crop‐raiding) in tropical ecosystems directly affects the livelihoods of local agriculturalists, which erodes their support for conserving biodiversity. We used data collected between 2013 and 2015 from 132 camera‐trap stations and responses from 157 interviewees representing 47 semi‐subsistence communities to quantify and contextualize terrestrial vertebrate crop‐raiding damage to manioc (Manihot esculenta) agricultural fields (i.e., roçados) in the Médio‐Juruá region of western Brazilian Amazonia. The 5 vertebrate species identified by respondents as the most damaging crop raiders were agoutis (Dasyprocta fuliginosa), collared peccaries (Pecari tajacu), pacas (Cuniculus paca), red brocket deer (Mazama americana), and spiny rats (family Echimyidae). These species were frequently detected by camera traps in early‐successional forests. Respondents reported mean manioc stem losses to crop raiders of 7.3%/roçado. Proportional losses of more palatable manioc varieties were approximately 3 times higher than more phytochemically defended varieties, further constraining crop choice. Respondents estimated that in the absence of active crop‐raider suppression, overall losses would have been 73.9%/respondent/annum, and therefore invested substantial effort in crop protection. Small communities, already economically disadvantaged by isolation from the material, service, and information monopoly of urban centers, were most affected by crop raiding. Although, the most damaging crop raiders are ideal candidates for sustainable subsistence hunting, we found only weak evidence of positive opportunities for agriculturalists to hunt crop raiders to compensate for crop losses. Our study indicated that crop raiding may continue to exacerbate the challenges inherent in tropical agriculture and represents a significant forest ecosystem disservice. © 2018 The Wildlife Society.
Unilateral radiotherapy treatment for p16/human papillomavirus–positive squamous cell carcinoma of unknown primary in the head and neck
Authors: Tiong Albert , Rischin Danny , Young Richard J. , Herschtal Alan , Solomon Ben , D'Costa Ieta , Fua Tsien , Liu Chen , Coleman Andrew , Kleid Stephen , Dixon Benjamin J. , Corry June 
Published: February 2018

Objectives/HypothesisThe outcomes of unilateral radiotherapy treatment for patients with p16/HPV‐positive squamous cell carcinomas of unknown primary (SCCUP) affecting cervical lymph nodes are under‐reported. Compared to radiating large volumes of the pharyngeal axis (the more common approach), this is potentially a much less toxic treatment for a good prognosis group.Study DesignRetrospective cohort study.MethodsWe identified patients with SCCUP who were treated radically at our center and did not have parotid or isolated level IV or V nodal involvement. Failure‐free and overall survivals were calculated using Kaplan‐Meier methods.ResultsFrom 2004 to 2012, there were 49 radically treated patients with SCCUP. Fourteen patients had bilateral neck treatment (they had bilateral nodal disease or suspected lesions in the base of tongue, though not proven with biopsy), two had surgery alone, whereas 33 had unilateral radiotherapy (after neck dissection, excisional biopsy, or definitively with concurrent chemotherapy). Of the 33 patients, 21 tested positive to p16/HPV and had median follow‐up of 57 months. In this group, no isolated contralateral neck failures or putative primaries emerged. There was 1/21 (4.3%) ipsilateral neck failure, 1/21 (4.3%) concurrent contralateral neck and distant failure, and 1/21 (4.3%) patient with distant failure. The 5‐year freedom from failure was 78% (95% confidence interval [CI]: 56%‐100%) and overall survival was 90% (95% CI: 79%‐100%).ConclusionsWith no emergence of putative primaries and no isolated contralateral neck failures, this single‐institution experience in p16/HPV‐positive SCCUP patients suggests that unilateral radiotherapy may be an underutilized management strategy.Levels of Evidence4 Laryngoscope, 128:2076–2083, 2018
Aggregation Behavior of Poly(3‐hexylthiophene) in Solvent Mixtures: Linear Solvation Energy Relationship (LSER) Modeling and COSMO‐RS Calculations
Authors: Sapolsky Marni , McFaddin John , Boucher David 
Published: February 2018

AbstractThe solubility and self‐assembly behavior of poly(3‐hexylthiophene) (P3HT) in solvent mixtures, and the dominant intermolecular forces related to these attributes, have only been partially scrutinized. In this work, the extent of aggregation of amorphous P3HT and the structural order of P3HT aggregates (Mn ≈ 20 kDa and Mn ≈ 75 kDa) are investigated in 54 solvent mixtures of chloroform with acetone, acetonitrile, dichloromethane, ethyl acetate, ethanol, and n‐hexane. Correlations between the molecular mass, the extent of aggregation, the structural order of the aggregates, and the nature of the solvent‐P3HT interactions are studied using a (1) linear solvation energy relationship (LSER) modeling and (2) solubility parameter‐based Flory–Huggins interaction parameters, χ. In addition, COSMO‐RS calculations are used to assess correlations between the extent of aggregation and the activity coefficients, γ, of P3HT. The results reveal that the extent of aggregation and the structural order of the P3HT aggregates are governed by different solvent–P3HT interactions. LSER modeling shows that the nucleophilicity and polarity of the solvent blends are the principal determinant of the structural order of P3HT aggregates. This result, which is based on an independent experimental method, supports previous computational results using COSMO‐RS σ‐profiles to assess the nucleophilicity and polarity of the solvent.
Reversible Supramolecular Polylactides Gels Obtained via Stereocomplexation
Authors: Michalski Adam , Socka Marta , Brzeziński Marek , Biela Tadeusz 
Published: February 2018

AbstractIn this paper, stereocomplexation is used as a driving force for the formation of 3D polymer networks by hydrogen bonding cross‐linking between complementary enantiomeric polylactides (PLAs). Thus, the formation of the gels after the mixing of equimolar solutions of l‐ and d‐star‐shaped PLAs in the biocompatible N‐methyl‐2‐pyrrolidone (NMP) is observed. The utility of star‐shaped polymers facilitates the cross‐linking of macromolecules by increasing the number of functional end groups. Moreover, the well‐established reaction with succinic anhydride is used to functionalize the star‐shaped PLAs with carboxylic functions. These end groups have a significant impact on the viscosity and stability of the resulting PLA gels. Importantly, the formation of the supramolecular gel is reversible, and it can return to sol upon heating. These results demonstrate that the gel formation is a result of a synergic interaction of the PLA functional end groups and stereocomplexation. These novel stereocomplex gels have potential for biomedical applications due to the biocompatibility of both components: PLA and NMP.
Horizontal Dendritic Stacking of Methanofullerene Single Crystals upon Diffusion‐Limited Aggregation
Authors: Wu Ching‐Feng , Lo Jui‐Hsien , Wang Chen‐An , Ruan Jrjeng 
Published: February 2018

AbstractWithin the binary amorphous homogeneous mixtures of conjugated polyalkylfluorene and methanofullerene, the annealing‐induced nucleation and growth of methanofullerene single crystals under the influences of molecular supply and mixing tendency have been studied in this research. As the molecular supply is satisfactory at selected annealing temperatures, the crystallization of methanofullerene is identified to advance mainly via the concurrent growth of board‐like crystals. When the diffusion is relatively limited, the local self‐aggregation of methanofullerene retards the further growth of preexistent crystals. Consequently, the successive nucleation of new single crystals on preexistent crystals emerges as the dominant mechanism of crystallization. With the advance of horizontal stacking of single crystals, the fractal‐like stacking patterns are able to evolve with long‐range continuity and facilitate the charge transportation. Nevertheless, upon the increase of annealing temperature and side‐chain length, the mixing tendency is enhanced, declining the tendency of self‐aggregation and thus successive horizontal stacking of single crystals.
X‐ray‐induced acoustic computed tomography for 3D breast imaging: A simulation study
Authors: Tang Shanshan , Yang Kai , Chen Yong , Xiang Liangzhong 
Published: February 2018

PurposeThe objective of this study is to demonstrate the feasibility of x‐ray‐induced acoustic computed tomography (XACT) for early breast un‐palpable microcalcification (μCa) detection in three dimensions (3D). The proposed technique provides the true 3D imaging for breast volume which overcomes the disadvantage of the tissue superposition in mammography.MethodsA 3D breast digital phantom was rendered from two‐dimensional (2D) breast CT slices. Three different tissue types, including the skin, adipose tissue, and glandular tissue, were labeled in the 3D breast phantom. μCas were manually embedded in different locations inside the breast phantom. For each tissue type, the initial pressure rise caused by the x‐ray‐induced acoustic (XA) effect was calculated according to its themoacoustic properties. The XA wave's propagation from the point of generation and its detection by ultrasound detector array were simulated by Matlab K‐Wave toolbox. The 3D breast XACT volume with μCa was acquired without tissue superposition, and the system was characterized by μCas placed at different locations.ResultsThe simulation results illustrated that the proposed breast XACT system has the ability to show the μCa cluster in 3D without any tissue superposition. Meanwhile, μCa as small as 100 μm in size can be detected with high imaging contrast, high signal to noise ratio (SNR), and high contrast to noise ratio (CNR). The dose required by the proposed XACT configuration was calculated to be 0.4 mGy for a 4.5 cm‐thick compressed breast. This is one‐tenth of the dose level of a typical two‐view mammography for a breast with the same compression thickness.ConclusionsThe initial exploration for the feasibility of 3D breast XACT has been conducted in this study. The system feasibility and characterization were illustrated through a 3D breast phantom and simulation works. The 3D breast XACT with the proposed system configuration has great potential to be applied as a low‐dose screening and diagnostic technique for early un‐palpable lesion in the breast.
Gradient waveform pre‐emphasis based on the gradient system transfer function
Authors: Stich Manuel , Wech Tobias , Slawig Anne , Ringler Ralf , Dewdney Andrew , Greiser Andreas , Ruyters Gudrun , Bley Thorsten A. , Köstler Herbert 
Published: February 2018

PurposeThe gradient system transfer function (GSTF) has been used to describe the distorted k‐space trajectory for image reconstruction. The purpose of this work was to use the GSTF to determine the pre‐emphasis for an undistorted gradient output and intended k‐space trajectory.MethodsThe GSTF of the MR system was determined using only standard MR hardware without special equipment such as field probes or a field camera. The GSTF was used for trajectory prediction in image reconstruction and for a gradient waveform pre‐emphasis. As test sequences, a gradient‐echo sequence with phase‐encoding gradient modulation and a gradient‐echo sequence with a spiral read‐out trajectory were implemented and subsequently applied on a structural phantom and in vivo head measurements.ResultsImage artifacts were successfully suppressed by applying the GSTF‐based pre‐emphasis. Equivalent results are achieved with images acquired using GSTF‐based post‐correction of the trajectory as a part of image reconstruction. In contrast, the pre‐emphasis approach allows reconstruction using the initially intended trajectory.ConclusionThe artifact suppression shown for two sequences demonstrates that the GSTF can serve for a novel pre‐emphasis. A pre‐emphasis based on the GSTF information can be applied to any arbitrary sequence type.
N‐methyl‐d‐aspartate receptor dysfunction in the prefrontal cortex of stroke‐prone spontaneously hypertensive rat/Ezo as a rat model of attention deficit/hyperactivity disorder
Authors: Shikanai Hiroki , Oshima Nobuhiro , Kawashima Hidekazu , Kimura Shin‐ichi , Hiraide Sachiko , Togashi Hiroko , Iizuka Kenji , Ohkura Kazue , Izumi Takeshi 
Published: February 2018

AbstractAimWe previously reported that stroke‐prone spontaneously hypertensive rat/Ezo (SHRSP/Ezo) has high validity as an attention deficit/hyperactivity disorder (AD/HD) animal model, based on its behavioral phenotypes, such as inattention, hyperactivity, and impulsivity. Fronto‐cortical dysfunction is implicated in the pathogenesis of AD/HD. In this study, we investigated prefrontal cortex (PFC) function in SHRSP/Ezo rats by electrophysiological methods and radioreceptor assay.MethodsWe recorded excitatory postsynaptic potential in layer V pyramidal neurons in the PFC by intracellular recording method to assess synaptic plasticity in the form of long‐term potentiation (LTP). We also performed N‐methyl‐d‐aspartate acid (NMDA) receptor binding assay in the PFC and hippocampus using radiolabeled NMDA receptor antagonist [3H]MK‐801.ResultsTheta‐burst stimulation induced LTP in the PFC of genetic control, WKY/Ezo, whereas failed to induce LTP in that of SHRSP/Ezo. The Kd value of [3H]MK‐801 binding for NMDA receptors in the PFC of SHRSP/Ezo was higher than in the WKY/Ezo. Neither the Bmax nor Kd of [3H]MK‐801 binding in the SHRSP/Ezo hippocampus was significantly different to WKY/Ezo.ConclusionThese results suggest that the AD/HD animal model SHRSP/Ezo has NMDA receptor dysfunction in the PFC.
2‐Alkyl‐3‐methoxypyrazines are potent attractants of florivorous scarabs (Melolonthidae, Cyclocephalini) associated with economically exploitable Neotropical palms (Arecaceae)
Authors: Maia Artur Campos Dália , Santos Geanne Karla Novais , Gonçalves Eduardo Gomes , Navarro Daniela Maria do Amaral Ferraz , Nuñez‐Avellaneda Luis Alberto 
Published: February 2018

AbstractBACKGROUND2‐Alkyl‐3‐methoxypyrazines (MPs) are naturally occurring aromatic compounds involved in insect chemical communication as both pheromones and allelochemicals. Although rarely characterized in floral scents, they have been identified as major constituents in headspace samples from palm inflorescences and evidence pointed towards their function as attractive cues for scent‐oriented pollinators, as well as florivores. In this study, we investigated the occurrence of MPs in economically exploitable palms belonging to Acrocomia and Attalea through headspace floral scent analysis and assessed their role in the selective attraction of flower‐feeding cyclocephaline scarabs (Melolonthidae, Cyclocephalini) in field bioassays conducted in Brazil and Colombia.RESULTSThree different MPs were identified among floral headspace samples of Acrocomia aculeata, Acr. intumescens, Attalea butyracea and Att. insignis: 2‐isopropyl‐3‐methoxypyrazine (IPMP), 2‐isobutyl‐3‐methoxypyrazine (IBMP) and 2‐(sec‐butyl)‐3‐methoxypyrazine (SBMP). Their combined estimated total scent emissions per inflorescence ranged from 246 μg h−1 to 6.2 mg h−1. Scented traps, individually baited with either IPMP or SBMP, resulted in species‐selective and high yield captures of Cyclocephala amazona and C. distincta, known florivores associated with over 20 different species of Neotropical palms.CONCLUSIONSThe identification of MPs as potent kairomones could prove instrumental in integrated pest management plans for these insects in emerging oil‐yielding crops in South America, including those of the wine palm (Att. butyracea) and macaw palms (Acrocomia spp.). © 2018 Society of Chemical Industry
Phosphorescence “Turn‐On” Sensing of Anions by Rhenium(I) Schiff‐Base Complexes
Authors: Ramdass Arumugam , Sathish Veerasamy , Velayudham Murugesan , Thanasekaran Pounraj , Rajagopal Seenivasan 
Published: February 2018

AbstractMonometallic rhenium(I) polypyridine complexes (1‐4) having imine functionalized phenol moieties based on 2,2’‐bipyridine ligands L1‐L4 have been used as phosphorescent turn‐on sensors for anions. These complexes showed various degrees of response to F–, CN–, CH3COO– and H2PO4– anions in the UV‐vis absorption spectra and displayed a phosphorescence “turn‐on” sensor for F–, CN–, CH3COO– and H2PO4– anions with different sensitivities. There is a substantial increase in emission intensity, quantum yield and luminescence lifetime is observed through deprotonation of the phenolic OH proton in 1–4 upon the addition of these anions. The signaling mechanism relies on the formation of acid‐base equilibrium through a set of well‐defined isosbestic points between 1–4 and anions, giving high equilibrium constants in the order F–>CN–>CH3COO–>H2PO4– with a 1:1 binding stoichiometry. The selectivity and sensitivity towards F− were explained in terms of H‐bonding interaction between 1–4 and F−, then deprotonation of 1–4 by 1H NMR titration analysis. The excellent selectivity of 1–4 for F– is ascribed to the fitness in the acidity of its phenolic OH‐group, which is able to discern the subtle difference in the affinity of F–, CN–, CH3COO– and H2PO4–ions to OH proton of phenolic group.
Review of Carbon Materials for Lithium‐Sulfur Batteries
Authors: Li Shanshan , Jin Bo , Zhai Xiaojie , Li Huan , Jiang Qing 
Published: February 2018

AbstractLithium‐sulfur battery as one of the most promising and attractive candidate among the emerging electrical energy storage has attracted enormous attentions. It has superior characteristics of high specific energy density (2600 Wh kg−1) and high theoretical specific capacity (1675 mAh g−1), which is equal to 3–5 times of lithium‐ion batteries, and more closed to the requirement of the pure electric vehicles and hybrid electric vehicles. Furthermore, sulfur element is inexpensive, naturally abundant, and environmentally friendly. However, the commercial application of lithium‐sulfur batteries (LSBs) still faces some major technical obstacles such as the low electrical conductivity of sulfur, the shuttle effect of polysulfides, and the drastic volume expansion during charge/discharge process. In this review paper, we focus on some of the effective strategies in boosting the electrochemical performance of LSBs through the development of sulfur/carbon composite electrode materials, including the use of porous carbons, carbon nanotubes/fibers, and graphene. The integration of carbon materials and sulfur can efficiently improve the utilization of active materials, enhance the conductivity of cathode materials, and provide a polysulfides barrier. Simultaneously, the challenges and prospects on LSBs in the near future are also presented and discussed.
Efficient Catalyst‐Free Trans Sulfonamidation/Sulfonamide Metathesis under Mild Conditions
Authors: Ramkumar Rajagopal , Chandrasekaran Srinivasan 
Published: February 2018

AbstractAn efficient, catalyst‐free chemo selective protocol for the N‐tosyl metathesis of 1,2,3‐triazoles/ N‐tosyl heteroaromatic compounds with various amines at room temperature is reported. This effective procedure would be useful for the detosylation of 1,2,3‐triazoles/ N‐tosyl heteroaromatic compounds as well as N‐tosylation of amines.
Direct Visualization of Ligands Exchange on the Surfaces of Quantum Dots by a Two‐Phase Approach
Authors: Nie Xiaobo , Zhang Ying , Wang Xiaojuan , Ren Chunguang , Gao Shu‐Qin , Lin Ying‐Wu 
Published: February 2018

AbstractSemiconductor quantum dots (QDs) have a wide range of applications owing to their uniquely photoelectric performance. It is helpful to modify QDs with desired polymer chains for improving their steric stabilization and compatibilization. Although various strategies have been successfully developed to graft polymer chains onto the surfaces of QDs, few methods can directly monitor the process of grafting. In this study, we took advantages of the color labels of QDs and developed a simple and convenient “grafting‐to” method by ligand exchange, which occurred in a two‐phase system with direct visualization. Briefly, cadmium selenide@cadmium sulphide core‐shell QDs capped by n‐trioctylphosphine oxide (TOPO‐CdSe@CdS QDs), dispersed in n‐hexane, and amino/thiol terminated polystyrene (PS‐NH2/PS‐SH), dissolved in N,N‐dimethylformamide (DMF), were mixed to form a novel two‐phase system. A direct visualization of the QDs from n‐hexane to DMF confirmed the ligand exchange on the surfaces of QDs. Further evidences for the ligand exchange were provided by both Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H NMR) studies, as well as by the grafting density of the PS on the surface of QDs. The PS‐grafted QDs can improve the compatibility with the polymers chemically or structurally similar to PS, which makes them useful as functional additives in the polymer matrix to construct nanocomposites with desired optical and mechanical properties.