bluuebunny/crossref_metadata_2025_split huggingface dataset:
Encapsulating Co2P@C Core–Shell Nanoparticles in a Porous Carbon Sandwich as Dual‐Doped Electrocatalyst for Hydrogen Evolution
Authors: Yang Yuanyuan , Liang Xiongyi , Li Feng , Li Shuwen , Li Xinzhe , Ng Siu‐Pang , Wu Chi‐Man Lawrence , Li Rong 
Published: October 2017

AbstractA highly efficient and pH‐universal hydrogen evolution reaction (HER) electrocatalyst with a sandwich‐architecture constructed using zero‐dimensional N‐ and P‐dual‐doped core–shell Co2P@C nanoparticles embedded into a 3 D porous carbon sandwich (Co2P@N,P‐C/CG) was synthesized through a facile two‐step hydrothermal carbonization and pyrolysis method. The interfacial electron transfer rate and the number of active sites increased owing to the synergistic effect between the N,P‐dual‐doped Co2P@C core–shell and sandwich‐nanostructured substrates. The presence of a high surface area and large pore sizes improved the mass‐transfer dynamics. This nanohybrid showed remarkable electrocatalytic activity toward the HER in a wide pH range with good stability. The computational study and experiments revealed that the carbon atoms close to the N and P dopants on the shell of Co2P@N,P‐C were effective active sites for HER catalysis and that both Co2P and the N,P dopants gave rise to an optimized binding free energy of H on the active sites.
Comparison of two photographic methodologies for collecting and analyzing the condition of coral reef ecosystems
Authors: Bryant D. E. P. , Rodriguez‐Ramirez A. , Phinn S. , González‐Rivero M. , Brown K. T. , Neal B. P. , Hoegh‐Guldberg O. , Dove S. 
Published: October 2017

AbstractCoral reefs are declining rapidly in response to unprecedented rates of environmental change. Rapid and scalable measurements of how benthic ecosystems are responding to these changes are critically important. Recent technological developments associated with the XL Catlin Seaview Survey have begun to provide high‐resolution 1‐m2 photographic quadrats of ~1.8–2 km of coral reefs at 10 m depth by using a semi‐autonomous image collection SeaView II camera system (SVII). The rapid collection of images by SVII can result in images being taken at a variable distance (1–2 m) from the substrate as well as having natural light variability between images captured. This variability can affect the quality of taxonomic resolution archived from photographic quadrats captured by SVII. Conventional approaches for taking photographic quadrats of coral reefs involve taking images from a fixed distance with the use of artificial light. These methods often provide images that enable high taxonomic resolution, but are typically used to cover areas of 50–150 m. Here, we select key metrics associated with coral reef condition from a functional perspective to contrast how much is lost in terms of association and agreement from image annotations using SVII images (1‐m2 photoquadrats) compared to conventional methods, capturing 0.5‐m2 photoquadrats using a digital single lens reflex camera from a fixed height of 0.5 m above the benthos. Comparisons were made over the same 50‐m linear transects at 15 sites in the Maldives. Photoquadrats were manually analyzed using an online image annotation tool and image repository called coral net with 25 randomly placed dots per 0.5 m2 of a quadrat. Our results reveal high levels of correlation and agreement between methods when measuring the abundance of hard corals as a functional group and individual labels, which make up hard corals as a functional group. These results demonstrate the two methods are comparable when measuring functional groups and coral communities on coral reefs. Therefore, involving rapid semi‐automated technologies that maximize data collection for monitoring coral reefs does not necessarily imply that taxonomic resolution is compromised. This insight has important ramifications for detecting important changes in coral reef condition, such as a decline in coral cover or shifts in benthic community composition.
Two Sustainability Epistemologies in the Marketization of a Natural Resource
Authors: Säwe Filippa , Hultman Johan 
Published: October 2017

AbstractThe normative implications of sustainable development mean that different understandings of how sustainability should be achieved will either facilitate or put at risk different values associated with economic, environmental and social aspects of sustainability. By a qualitative analysis of Swedish fishery legislation documents, we analyse and outline the consequences of two different and competing sustainability epistemologies: a top‐down system understanding and a bottom‐up experiential understanding. To define these two epistemologies, the case study adopts discourse analysis on one fishery law and one fishery regulation proposal, and the remittance answers to these documents. We demonstrate how a top‐down system approach shapes social reality according to its own logic of efficiency, and that pre‐defined principles of economic optimization prevail over social experience and continuity. We conclude that qualitative analysis holds promise to expand the understanding of the premises and consequences of alternative environmental governance trajectories due to its ability to uncover social constructions of meaning. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
A numerical study on the feasibility of evaluating CO2injection wellbore integrity through casing deformation monitoring
Authors: Li Yurong , Nygaard Runar 
Published: October 2017

AbstractDistributed sensing technologies have been increasingly used for downhole monitoring in the oil field in recent years. A casing deformation monitoring system based on distributed strain sensors has been developed and proposed for wellbore integrity monitoring. However, due to the lack of field data on casing deformation induced by various exploration and development activities, the relationship between casing deformation and wellbore integrity remains unclear. To study the feasibility of evaluating short‐term CO2injection wellbore integrity through casing deformation monitoring, a staged finite element analysis is conducted for an existing well in the Weyburn field to study the relationship between casing deformation and wellbore integrity during CO2injection. The model is generated with HypermeshTMand the analysis is conducted with AbaqusTM. The staged finite element model applies loads and materials in multiple steps to replicate the actual drilling process. The wellbore stress, casing strain, and interface gap distance change at the surface casing shoe and production casing shoe are calculated. A parametric study is also conducted to study the effect of various parameters on CO2injection wellbore integrity in the Weyburn field. The result shows that the casing deformation can be correlated to the wellbore integrity by cement expansion/shrinkage through its effect on the interface gap distance change and the stress difference between wellbore components induced by CO2injection. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd.
Dendrites, deep learning, and sequences in the hippocampus
Authors: Bhalla Upinder S. 
Published: October 2017

AbstractThe hippocampus places us both in time and space. It does so over remarkably large spans: milliseconds to years, and centimeters to kilometers. This works for sensory representations, for memory, and for behavioral context. How does it fit in such wide ranges of time and space scales, and keep order among the many dimensions of stimulus context? A key organizing principle for a wide sweep of scales and stimulus dimensions is that of order in time, or sequences. Sequences of neuronal activity are ubiquitous in sensory processing, in motor control, in planning actions, and in memory. Against this strong evidence for the phenomenon, there are currently more models than definite experiments about how the brain generates ordered activity. The flip side of sequence generation is discrimination. Discrimination of sequences has been extensively studied at the behavioral, systems, and modeling level, but again physiological mechanisms are fewer. It is against this backdrop that I discuss two recent developments in neural sequence computation, that at face value share little beyond the label “neural.” These are dendritic sequence discrimination, and deep learning. One derives from channel physiology and molecular signaling, the other from applied neural network theory ‐ apparently extreme ends of the spectrum of neural circuit detail. I suggest that each of these topics has deep lessons about the possible mechanisms, scales, and capabilities of hippocampal sequence computation.
Headwaters to oceans: Ecological and biogeochemical contrasts across the aquatic continuum
Authors: Xenopoulos Marguerite A. , Downing John A. , Kumar M. Dileep , Menden‐Deuer Susanne , Voss Maren 
Published: October 2017

AbstractWhile the disciplines of oceanography and limnology often operate in isolate, freshwater, estuarine, and marine ecosystems are intricately linked. The emphasis of this special issue for Limnology and Oceanography is on the aquatic continuum and the connectivity between aquatic ecosystems from headwater streams and inland waters, to coastal and marine systems. Changes in the transport and transformation of elements as well as ecological functions occur along this aquatic continuum. Assemblages of organisms change in a way that reflects the ecological and biogeochemical conditions of the aquatic gradient. Here, we highlight research progress in limnology and oceanography across the aquatic continuum and at the interfaces of headwaters to oceans. Contributions explored nutrient and carbon dynamics which included release, transportation, transformation, and stoichiometry from freshwaters to marine. The special issue also explored food web continua, including functional changes, biodiversity gradients, and photosynthesis and respiration comparisons among ecosystems at different points in the continuum. Rapid improvements in biomolecular techniques, use of long‐term datasets, applications of novel statistical methods, and improved upscaling methods can transform the way aquatic scientists are describing biological organisms and communities from freshwaters to oceans. One important conclusion is the recognition that anthropogenic activities such as invasive species and nutrient pollution trigger challenge the current concepts of aquatic continua including the river continuum concept, the land to ocean continuum, river to estuary systems, and the submarine groundwater discharge. Both limnologists and oceanographers have much to gain from exchanging information with one another, especially in light of global change.
Benthic N pathways in illuminated and bioturbated sediments studied with network analysis
Authors: Magri M. , Benelli S. , Bondavalli C. , Bartoli M. , Christian R. R. , Bodini A. 
Published: October 2017

AbstractThe regulation of benthic nitrogen (N) cycling by multiple interactions among bacteria, macrofauna, and primary producers is poorly understood. We hypothesized that a biodiverse benthic system should better exploit the benthic N‐availability and retain N than a simpler one. Retention occurs by avoiding losses both to the water column via increased recycling and to the atmosphere via decreased N2 fluxes and by limiting energy‐costly processes as N‐fixation. We also hypothesized that primary producer‐bacterial competition is reduced in the presence of macrofauna due to mobilization of refractory N pools. To this purpose, the effects of two bioturbators (the detritivorous Sparganophilus tamesis and the filter‐feeding Corbicula spp.) and two primary producer growth forms (the rooted macrophyte Vallisneria spiralis and microphytobenthos) on benthic N cycling were studied. An array of N‐processes were measured along a complexity gradient (from bare sediments to all combinations of the above mentioned organisms), and experimental outcomes were analyzed via ecological network analysis (ENA). This suite of algorithms, applied to the microscale, revealed differential partitioning of N fluxes among bare sediments (highest denitrification rates), sediments with macrofauna (highest recycling), and sediments with rooted plants (highest N‐fixation). N2 losses and inputs were significantly reduced when all components were represented, and N requirements by primary producers were to a large extent supported by the activity of macrofauna. Ecological interactions in biodiverse benthic systems promoted an efficient exploitation of sedimentary N pools, increased the coupling between recycling and uptake, and maximized N use efficiency at the expenses of losses and imports.
Using probability of drug use as independent variable in a register‐based pharmacoepidemiological cause‐effect study—An application of the reverse waiting time distribution
Authors: Hallas Jesper , Pottegård Anton , Støvring Henrik 
Published: October 2017

AbstractBackgroundIn register‐based pharmacoepidemiological studies, each day of follow‐up is usually categorized either as exposed or unexposed. However, there is an underlying continuous probability of exposure, and by insisting on a dichotomy, researchers unwillingly force a nondifferential misclassification into their analyses. We have recently developed a model whereby probability of exposure can be modeled, and we tested this on an empirical case of nonsteroidal anti‐inflammatory drug (NSAID)‐induced upper gastrointestinal bleeding (UGIB).MethodsWe used a case‐controls data set, consisting of 3568 cases of severe UGIB and 35 552 matched controls. Exposure to NSAID was based on 3 different conventional dichotomous measures. In addition, we tested 3 probabilistic exposure measures, a simple univariate backward‐recurrence model, a “full” multivariable model, and a “reduced” multivariable model. Odds ratios (ORs) and 95% confidence intervals for the association between NSAID use and UGIB were calculated by conditional logistic regression, while adjusting for preselected confounders.ResultsCompared to the conventional dichotomous exposure measures, the probabilistic exposure measures generated adjusted ORs in the upper range (4.37‐4.75) while at the same time having the most narrow confidence intervals (ratio between upper and lower confidence limit, 1.46‐1.50). Some ORs generated by conventional measures were higher than the probabilistic ORs, but only when the assumed period of intake was unrealistically short.ConclusionThe pattern of high ORs and narrow confidence intervals in probabilistic exposure measures is compatible with less nondifferential misclassification of exposure than in a dichotomous exposure model. Probabilistic exposure measures appear to be an attractive alternative to conventional exposure measures.
The effects of processing parameters on the morphology of PLA/PEG melt electrospun fibers
Authors: Nazari Tayebe , Garmabi Hamid 
Published: October 2017

AbstractElectrospinning of a polymer melt is an ideal technique to produce highly porous nanofibrous or microfibrous scaffolds appropriate for biomedical applications. In recent decades, melt electrospinning has been known as an eco‐friendly procedure as it eliminates the cytotoxic effects of the solvents used in solution electrospinning. In this work, the effects of spinning conditions such as temperature, applied voltage, nozzle to collector distance and collector type as well as polyethylene glycol (PEG) concentration on the diameter of melt electrospun polylactic acid (PLA)/PEG fibers were studied. The thermal stability of PLA/PEG blends was monitored through TGA and rheometry. Morphological investigations were carried out via optical and scanning electron microscopy. Based on the results, blends were almost stable over the temperature range of melt electrospinning (170 − 230 °C) and a short spinning time of 5 min. To obtain non‐woven meshes with uniform fiber morphologies, experimental parameters were optimized using ANOVA. While increasing the temperature, applied voltage and PEG content resulted in thinner fibers, PEG concentration was the most influential factor on the fiber diameter. In addition, a nozzle to collector distance of 10 cm was found to be the most suitable for preparing uniform non‐woven PLA/PEG meshes. At higher PEG concentrations, alterations in the collector distance did not affect the uniformity of fibers, although at lower distances vigorous bending instabilities due to polarity augmentation and viscosity reduction resulted in curly fibrous meshes. Finally, the finest and submicron scale fibers were obtained through melt electrospinning of PLA/PEG (70/30) blend collected on a metallic frame. © 2017 Society of Chemical Industry
Design of 3D Graphene‐Oxide Spheres and Their Derived Hierarchical Porous Structures for High Performance Supercapacitors
Authors: Li Zhuangnan , Gadipelli Srinivas , Yang Yuchen , Guo Zhengxiao 
Published: October 2017

AbstractGraphene‐oxide (GO) based porous structures are highly desirable for supercapacitors, as the charge storage and transfer can be enhanced by advancement in the synthesis. An effective route is presented of, first, synthesis of three‐dimensional (3D) assembly of GO sheets in a spherical architecture (GOS) by flash‐freezing of GO dispersion, and then development of hierarchical porous graphene (HPG) networks by facile thermal‐shock reduction of GOS. This leads to a superior gravimetric specific capacitance of ≈306 F g−1 at 1.0 A g−1, with a capacitance retention of 93% after 10 000 cycles. The values represent a significant capacitance enhancement by 30–50% compared with the GO powder equivalent, and are among the highest reported for GO‐based structures from different chemical reduction routes. Furthermore, a solid‐state flexible supercapacitor is fabricated by constructing the HPG with polymer gel electrolyte, exhibiting an excellent areal specific capacitance of ≈220 mF cm−2 at 1.0 mA cm−2 with exceptional cyclic stability. The work reveals a facile but efficient synthesis approach of GO‐based materials to enhance the capacitive energy storage.
Word maturity indices with latent semantic analysis: why, when, and where is Procrustes rotation applied?
Authors: Jorge‐Botana Guillermo , Olmos Ricardo , Luzón José M. 
Published: October 2017

The aim of this paper is to describe and explain one useful computational methodology to model the semantic development of word representation: Word maturity. In particular, the methodology is based on the longitudinal word monitoring created by Kirylev and Landauer using latent semantic analysis for the representation of lexical units. The paper is divided into two parts. First, the steps required to model the development of the meaning of words are explained in detail. We describe the technical and theoretical aspects of each step. Second, we provide a simple example of application of this methodology with some simple tools that can be used by applied researchers. This paper can serve as a user‐friendly guide for researchers interested in modeling changes in the semantic representations of words. Some current aspects of the technique and future directions are also discussed. WIREs Cogn Sci 2018, 9:e1457. doi: 10.1002/wcs.1457This article is categorized under:

Computer Science > Natural Language Processing
Linguistics > Language Acquisition
Psychology > Development and Aging
The Clinical Implications of Liver Resection Margin Size in Patients with Hepatocellular Carcinoma in Terms of Positron Emission Tomography Positivity
Authors: Park Jae Hyun , Kim Dong Hwi , Kim Sung Hoon , Kim Moon Young , Baik Soon Koo , Hong In Su 
Published: October 2017

AbstractBackgroundThe positivity of positron emission tomography (PET) in hepatocellular carcinoma (HCC) correlates with aggressive tumor factors and poor survival. Adequate resection margin size is still a topic of debate. We analyzed the clinical implications of resection margin size in patients with HCC in terms of PET positivity.MethodsWe retrospectively reviewed the medical records of 92 patients who underwent liver resection from March 2012 to October 2015. We investigated prognostic factors for recurrence and survival. We analyzed the correlation of resection margin size and PET positivity. Resection margins were classified as less than 1 cm and more than 1 cm.ResultsTwenty six (31.3%) patients had PET‐positive HCC. Multivariate analysis showed PET, satellite nodules, microvessel invasion, and multicentric occurrence were significant prognostic factors for HCC recurrence. Multivariate analysis also showed satellite nodules and microscopic portal vein invasion were significant prognostic factors for overall survival (OS). Resection margin size did not affect disease‐free survival (DFS) (p = 0.681) or OS (p = 0.301) in patients with PET‐negative HCC, but showed a difference in DFS [<1 cm at 11 months vs. ≥1 cm at 41 months (p = 0.188)] and OS [<1 cm at 28 months vs. ≥1 cm at 48 months (p < 0.001)] in patients with PET‐positive HCC.ConclusionsPET has low sensitivity for HCC. However, it is useful to predict treatment outcomes after liver resection or liver transplantation for HCC. Although the extent of liver resection must be decided based on liver function, a resection margin size >1 cm may improve DFS and OS in patients with PET‐positive HCC.
Effects of Timing of Appendectomy on the Risks of Perforation and Postoperative Complications of Acute Appendicitis
Authors: Kim Jong Wan , Shin Dong Woo , Kim Doo Jin , Kim Jeong Yeon , Park Sung Gil , Park Jun Ho 
Published: October 2017

AbstractBackgroundIt is generally believed that appendectomy should be performed immediately to prevent perforation and complications. Therefore, our objectives were to investigate the effect of timing of appendectomy on the incidence of perforation and complications.MethodsWe retrospectively reviewed the medical records of patients who underwent laparoscopic appendectomy between January 2014 and June 2015. The time from symptom onset to appendectomy was categorized into three periods: time from symptom onset to hospital admission (symptomatic time), time from admission to appendectomy (hospitalization time), and time from symptom onset to appendectomy [symptomatic period + hospitalization period (overall time)]. Multivariable analyses were performed to identify independent factors associated with perforation and complications.ResultsA total of 1753 patients were included in the present study. Perforation occurred in 28.2% of patients, and postoperative complications occurred in 10.0% of patients. Multivariable analysis showed that BT > 38 °C (P = 0.006), WBC count >13,000 cells/µl (P = 0.02), neutrophil ratio >80% (P < 0.001), and symptomatic time >24 h (P < 0.001) were independent factors of appendiceal perforation, while the neutrophil ratio >80% (P < 0.001) and symptomatic time >48 h (P = 0.003) were independently associated with complications.ConclusionsThe present study showed that the symptomatic time and overall time were significantly associated with perforation and complications, whereas hospitalization time was not associated with either perforation or complications.