bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linking Three Gorges Dam and downstream hydrological regimes along the Yangtze River, China
Authors: Mei Xuefei , Dai Zhijun , van Gelder P. H. A. J. M. , Gao Jinjuan 
Published: March 2015

AbstractThe magnitude of anthropogenic influence, especially dam regulation, on hydrological system is of scientific and practical value for large river management. As the largest dam in the world by far, Three Gorges Dam (TGD) is expected to be a strong evidence on dam impacts on downstream hydrological regime. In this study, statistical methods are performed on the pre‐ and post‐TGD daily hydrological data at Yichang, Hankou, and Datong stations to detect the daily, monthly, yearly, and spatial fluctuations in river hydrology along the Yangtze River during the period of 2000–2013. It is found that TGD makes a significant hydrological variation along the Yangtze River following the dam operation since 2003. Specifically, the daily discharge and water level are gathered to normal event ranges with less extreme events than before 2003. Both maximum and minimum daily water levels at the study stations have decreased due to TGD‐induced riverbed incision. The operation of TGD shifts the maximum monthly discharge and water level from August to July at Yichang station. The significance of TGD effect on discharge and water level relationship presents spatial variation. The rating curves at upstream reach experience the most significant effects with a substantial upward shift, while those at lower reach only suggest slight modification. Of the potential drivers considered in this study, dam regulation is responsible for the changes in downstream river hydrology. Moreover, the tributary and adjoining riparian lakes of the Yangtze River contribute to weaken the effect of TGD on downstream hydrological behavior.
Spatial and temporal variations in crustal production at the Mid‐Atlantic Ridge, 25°N–27°30′N and 0–27 Ma
Authors: Wang Tingting , Tucholke Brian E. , Lin Jian 
Published: March 2015

AbstractWe use high‐resolution multibeam bathymetry, shipboard gravity, side‐scan sonar images, and magnetic anomaly data collected on conjugate flanks of the Mid‐Atlantic Ridge at 25°N–27°30′N and out to ~27 Ma crust to investigate the crustal evolution of the ridge. Substantial variations in crustal structure and thickness are observed both along and across isochrons. Along isochrons within spreading segments, there are distinct differences in seafloor morphology and gravity‐derived crustal thickness between inside and outside corners. Inside corners are associated with shallow depths, thin crust, and enhanced normal faulting while outside corners have greater depths, thicker crust, and more limited faulting. Across‐isochrons, systematic variations in crustal thickness are observed at two different timescales, one at ~2–3 Myr and another at >10 Myr, and these are attributed to temporal changes in melt supply at the ridge axis. The shorter‐term variations mostly are in‐phase between conjugate ridge flanks, although the actual crustal thickness can be significantly different on the two flanks at any given time. We observe no correlation between crustal thickness and spreading rate. Thus, during periods of low melt supply, tectonic extension must increase to accommodate the full plate separation rate. This extension commonly is concentrated in long‐lived faults on only one side of the axial valley, resulting in strong across‐axis asymmetries in crustal thickness and seafloor morphology. The thin‐crust flank has few volcanic features and exhibits elevated, blocky topography with large‐offset, often irregular faults, while the conjugate thicker‐crust flank shows shorter‐offset, regular faulting, and common volcanic features. The variations in melt supply at the ridge axis most likely are caused either by episodic convection in the subaxial mantle or by variable melting of chemically heterogeneous mantle.
High‐resolution acoustic mapping to understand the ore deposit in the Bayonnaise knoll caldera, Izu‐Ogasawara arc
Authors: Honsho Chie , Ura Tamaki , Asada Akira , Kim Kangsoo , Nagahashi Kenji 
Published: March 2015

AbstractWe collected deep‐sea multibeam, side scan, and subbottom profiler data using an autonomous underwater vehicle at the Bayonnaise knoll, a submarine caldera located in the rift zone of the Izu‐Ogasawara arc. We aimed to reveal topographic and geological features and the origin of a hydrothermal field called the Hakurei site in the caldera. We performed seafloor classification by textural analysis using calibrated side‐scan sonar data, which provided an effective means to understand the geology and to highlight potential areas of hydrothermal constructions. The high‐resolution bathymetric map illustrates that the Hakurei hydrothermal field is distributed over a landslide landform in the caldera wall. The distribution of hydrothermal vents indicates that the slip surface has served as a major route of hydrothermal fluids. The radial alignment of chimneys and mounds indicates radial routes of hydrothermal fluid and/or belching along fragile lines in the landslide landform. Various postcaldera activities are inferred including the formation of a lava dome, a pyroclastic cone, and subsequent phreatic explosions. A general volcano‐tectonic structure extending across the caldera in a NW‐SE direction is interpreted as an inferred boundary fault of the North Myojin Rift. Analogous to the Hokuroku basin and land kuroko deposits, it is suggested that the main contributing factor in the formation of kuroko deposits was volcano‐tectonic activity that dominated the margin of the back‐arc rift basin. The intersections between the margin of a rift basin and the surrounding knolls have a high potential for ore‐forming areas.
Classification of atmospheric river events on the U.S. West Coast using a trajectory model
Authors: Ryoo Ju‐Mee , Waliser Duane E. , Waugh Darryn W. , Wong Sun , Fetzer Eric J. , Fung Inez 
Published: March 2015

AbstractWe investigate transport pathways of water vapor associated with landfalling atmospheric river (AR) events that result in precipitation along the West Coast of the U.S. for winters of 1997–2010. The water vapor transport pathways are determined by computing back trajectories with a trajectory model using the Modern Era Retrospective analysis for Research and Applications reanalysis data set. The majority of AR events (86%) over the West Coast of the U.S. are grouped into three trajectory types, and two of them are closely associated with the AR events. We designate the first type as Ascending near landfall and of Tropical Origin (AT), the second type as Ascending near landfall and of Extratropical Origin (AE), and the third type as Descending or parallel near landfall and of Extratropical Origin (DE), which is accompanied but not directly associated with the AR events. The magnitude and spatial distribution of precipitation of a given AR event are found to be strongly determined by the type of trajectories. In general, AR events composed of both AT and AE trajectories have more frequent precipitation over a broad region of the western U.S. and AR events composed of both AT and DE trajectories have intense precipitation over the southwestern U.S. due to AT trajectories. AR events of AT‐only trajectories have intense precipitation, especially over the northwestern U.S., but are less frequent compared to those of AT + AE trajectories. In addition, different patterns of trajectory types among AR events are closely linked to upper level potential vorticity (PV) anomalies; 66% of AR events are associated with anticyclonic Rossby wave breaking events.
Iron: Models of Proteins with Dinuclear Active Sites
Authors: Chavez Ferman A. , Li Jia 
Published: March 2015

Abstract

This article focuses on recent developments in the area of synthetic model compounds for diiron enzymes. The archetypical enzyme in this class is soluble methane monooxygenase, a protein capable of hydroxylating methane as well as many other substrates. The article includes new diiron enzymes for which the X‐ray structures have been determined. These developments allow for synthetic chemists to focus on new coordination modes for model compounds. The versatility of the diiron site provides new challenges for modeling. The synthetic approaches are organized based on ligand types and assembly modes. These categories include the use of chelating ligands to generate mononuclear iron sites that are then coupled together by bridging ligands to generate the dinuclear site. Employment of trispyridyl ligands, used extensively by Que's group, is next addressed and separated from chelating ligands owing to their popularity and versatility. New developments in binucleating ligands first seen several decades ago are treated next and this is followed by the employment of bulky carboxylate ligands, mainly pioneered by Lippard's group, to control nuclearity and structure. The final topic is a new approach introduced by Lippard's group in which metal‐spanning ligands referred to as “platform ligands” are used to create
syn
nitrogen coordination. Overall, new developments have been in the area of reactivity where functional models have been developed. Although the goal of catalytically oxidizing external alkane and aromatic substrates under ambient conditions with dioxygen is coming closer to reality, this is yet to be achieved. The modeling approach will continue to provide valuable insights into catalytic mechanisms of dinuclear enzymes and will help in the development of green catalysts.
Membrane‐Bound Pyrophosphatases
Authors: Kellosalo Juho , Goldman Adrian 
Published: March 2015

AbstractMembrane‐bound pyrophosphatases (M‐PPases) are homodimeric enzymes that couple the vectorial transport of protons and/or sodium ions to pyrophosphate (PPi) hydrolysis or synthesis. They are found in prokaryotes, plants, and protists and are thus present in all three domains of life. M‐PPases have an important role in conferring tolerance against abiotic stress conditions and are also vital for plant maturation. Like many proteins that catalyze the formation or cleavage of phosphoanhydride bonds (e.g., P‐ and F‐type ATPases, soluble PPases), M‐PPases require magnesium for activity, both because they bind 2–3 free Mg2+ions and because the catalytically relevant substrate at physiological pH and Mg ion concentration is Mg2PPi. Besides this alkaline earth metal, M‐PPases also bind alkali metals: Na+‐pumping M‐PPases bind and transport Na+and certain M‐PPases bind and are activated by K+. In this article, we give a concise summary of the current structural and functional understanding of M‐PPases, with an emphasis on describing the role of the metal ions in the enzymatic function of these proteins.
Lytic Polysaccharide Monooxygenase
Authors: Aachmann Finn L , Vaaje‐Kolstad Gustav , Forsberg Zarah , Røhr Åsmund , Eijsink Vincent G H , Sørlie Morten 
Published: March 2015

AbstractFor decades, the enzymatic conversion of recalcitrant polysaccharides such as cellulose and chitin was thought to rely on the synergistic action of hydrolytic enzymes, but recent work has shown that lytic polysaccharide monooxygenases (LPMOs) are important contributors to this process. LPMOs that are divided into three auxiliary activities (AA) families share a structural fold, but there is no detectable sequence identity between members of different families. The general core structure of LPMOs is an immunoglobulin‐like distorted β‐sandwich fold, consisting of antiparallel β‐strands connected by loops with a varying number of α‐helix insertions. LPMOs have a flat binding surface that harbors a type‐2 copper center that is coordinated by three nitrogens with a T‐shaped geometry that has been referred to as the histidine brace. Two of the nitrogens come from the imidazole side chain and the main chain amino group of the N‐terminal histidine, whereas the third nitrogen is from a second conserved histidine. The role of the copper ion is to reduce dioxygen, which requires electrons from an external electron donor. The reduced dioxygen likely abstracts a hydrogen from the substrate, which eventually leads to cleavage of the β‐1,4 glycosidic linkage. While copper‐dependent enzymes usually use more than one metal to activate O2by multielectron reduction, LPMOs use only a single Cu center for catalysis. Central for LPMO activity is a flat protein surface with a few conserved residues suggesting a role in substrate binding and the T‐shape of the copper site that permits strong O2binding with very little reorganization energy allowing the thermodynamically difficult one‐electron reduction activating the oxygen.
Rhodium‐Catalyzed Direct C7 Alkynylation of Indolines
Authors: Jin Ning , Pan Changduo , Zhang Honglin , Xu Pan , Cheng Yixiang , Zhu Chengjian 
Published: March 2015

AbstractAn efficient rhodium(III)‐catalyzed direct C7 alkynylation of indoline CH bonds with the alkynylated hypervalent iodine reagents has been developed. This reaction proceeds smoothly under mild conditions over a wide structural scope with high site‐selectivity and excellent functional‐group tolerance. N‐Acetyl as well as other N‐acyls served as effective directing groups (DG). This procedure allows for the synthesis of a variety of 7‐alkynyl‐substituted indolines in good to excellent yield. More significantly, C7‐alkynylated indoles through further transformations have been successfully accessed.magnified image
Clinical and 22‐item Sino‐Nasal Outcome Test symptom patterns in primary headache disorder patients presenting to otolaryngologists with “sinus” headaches, pain or pressure
Authors: Lal Devyani , Rounds Alexis B. , Rank Matthew A. , Divekar Rohit 
Published: March 2015

BackgroundThe objective of this work was to study patient and 22‐item Sino‐Nasal Outcome Test (SNOT‐22) characteristics in primary headache disorders (PHDs).MethodsRetrospective chart review of “sinus” headache/pressure/pain patients was conducted. Patients that had rhinosinusitis excluded (negative endoscopy/computed tomography [CT]), and neurologist‐confirmed PHD were studied. Patterns in symptom and SNOT‐22 items were analyzed by network visualization and cluster analysis.ResultsForty‐six patients met study criteria. Forty‐three (93.5%) reported “need to blow nose” and 40 (86.9%) reported postnasal drainage. Sneezing was reported by 37 (80.4%) patients, “blockage/congestion of nose” by 33 (71.8%), and “runny nose by 32 (69.6%) patients. The median SNOT‐22 score was 54 (interquartile range [IQR], 40 to 63). Past history included neurological diagnoses (60%), rhinologic disease (39%; chronic rhinosinusitis [CRS], rhinitis, recurrent acute sinusitis), asthma (28%), and allergen‐sensitivity (26%). Previous sinonasal surgery had been performed in 41%. Network layout and cluster analysis identified 2 patient clusters and 2 symptom clusters. Two‐thirds (31) of patients formed a tight cluster (cluster 1) linking to a symptom cluster of psychosocial items wrapped tightly with “facial pain/pressure.” The remaining one‐third of patients (cluster 2) linked to rhinologic symptoms loosely grouped away from “facial pressure/pain.” In contrast to patients in cluster 2, patients in cluster 1 were predominantly female (p < 0.04), had significantly higher (p < 0.0001) median SNOT‐22 scores (60 vs 34; IQR, 53 to 67 vs 17 to 42), were more likely to have migraine history (p = 0.058), and reported being “sad” (p < 0.0001) or “embarrassed” (p < 0.006).ConclusionProminent rhinologic symptoms can be present in PHD patients in the absence of rhinosinusitis. In particular, high symptom‐burden/SNOT‐22 scores and high psychosocial symptoms should raise suspicion of PHD when endoscopy and/or CT results do not correlate with symptoms.
Identifying a suite of surrogate freshwaterscape fish species: a case study of conservation prioritization in Ontario's Far North, Canada
Authors: McDermid Jenni , Browne David , Chetkiewicz Cheryl‐Lesley , Chu Cindy 
Published: March 2015

Abstract

Freshwater ecosystems are among the most threatened ecosystems on the planet, yet freshwater fish species are frequently overlooked in conservation planning initiatives.
Ontario's Far North (OFN) in Canada is at present one of the largest relatively intact landscapes in North America with 11% of the total area covered by freshwater ecosystems, not including wetlands.
Resource development is being planned for OFN but due to the paucity of data on fish species and the freshwater ecosystems they inhabit, the freshwaterscape is largely being overlooked.
Given the importance of freshwater resources in OFN, existing information on fish species in OFN was compiled and assessed using the Landscape Species Approach (LSA) on this freshwaterscape. The LSA is a species‐based conservation planning tool developed for terrestrial conservation that is constructed around the identification of focal species for a given landscape.
An analysis of 14 large‐bodied candidate freshwater species, including their area requirements, habitat use, ecological function, socio‐economic function and vulnerability to threats was used to identify three freshwaterscape species: lake sturgeon, lake trout, and walleye.
The identification of these species and their ecological requirements suggests a starting place for research, management, and conservation of freshwater resources in OFN before large‐scale landscape changes.
Copyright © 2015 John Wiley & Sons, Ltd.
My Recency, Our Primacy: How Social Connection Influences Evaluations of Sequences
Authors: Bhargave Rajesh P. , Montgomery Nicole Votolato 
Published: March 2015

AbstractIndividuals have many life experiences (e.g., work and vacations) that consist of a series of interconnected episodes (i.e., temporal sequences). Assessments of such experiences are integral to daily life in that they facilitate future planning and behaviors for individuals. Therefore, these experiences often culminate in evaluations of their global affect. Past work has shown that retrospective, affective evaluations of these sequences generally exhibit an “end effect,” whereby a sequence's end intensity—but not its start intensity—is disproportionately weighted. Yet, researchers have largely investigated experiences that occur alone. In contrast, many real‐world experiences vary in their extent of social connection to others (e.g., working in an office with others versus alone in a cubicle). The present work fills this gap by showing the moderating role of social connection on how episodes are weighted in global affective ratings. Five studies involving two autobiographical experiences spanning several days each (workweek and spring break) and two brief simulated experiences show that high social connection leads to greater (lesser) weighting of the first (last) episode. To our knowledge, we are the first to demonstrate that these effects persist across different forms of social connection (i.e., interpersonal interaction versus semantic priming tasks) and are supported regardless of whether social connection occurs at encoding or retrieval of an experience. Copyright © 2015 John Wiley & Sons, Ltd.
Double Reference Points: the Effects of Social and Financial Reference Points on Decisions Under Risk
Authors: Lu Jingyi , Xie Xiaofei , Wang Mei , Tang Xin 
Published: March 2015

AbstractThe existing literature is inconsistent about how social comparison affects risk attitudes. We propose a framework where the total utility is composed of the social and financial utilities. The financial utility is consistent with prospect theory (i.e., an S‐shaped utility function with a financial reference point), whereas the social utility is affected by both social and financial reference points. Therefore, social risk attitudes are determined by interaction between gains/losses in both social and financial contexts. On the basis of safety‐first principle, we propose that when experiencing financial gains, individuals tend to seek upside potential and take social risks (i.e., a convex social utility function). In contrast, when facing financial losses, people would be more risk seeking in social gains but more risk averse in social losses to maximize security (i.e., an inverse S‐shaped utility function). We also propose that the relative importance of financial and social utilities depends on the saliency of the reference points and size of stakes. Studies 1 and 2 showed that individuals were risk seeking in both social gains and losses with social reference points alone. Studies 3 and 4 demonstrated that when both financial and social reference points were salient, participants were risk averse in both social gains and losses when facing financial gains, but risk seeking in social gains and risk averse in social losses when facing financial losses. The hypotheses derived from the theoretical framework were in general supported by our experiments. Copyright © 2015 John Wiley & Sons, Ltd.
Evaluation study of eLGuide: A framework for adaptive e‐learning
Authors: Zafar Aasim , Albidewi Ibrahim 
Published: March 2015

ABSTRACTThis paper outlines the design and development of an intelligent tutoring technique to personalize the navigation of individual users in the course content and generate advice to students. Based on that, a framework for adaptive e‐learning, the e‐Learning Guide system (eLGuide), is implemented and an empirical evaluation of the prototype is conducted to assess the possibility of its integration with web‐based learning systems. The system is tested in a real setting with the SQL—A Database Language course comprising postgraduate students of the computer science program, all new to database systems. The evaluation study shows a positive impact on learning outcomes. The results of the experimental study allowed us to conclude that eLGuide is a useful framework, which can be employed in a web‐based learning environment to support students as well as teachers in a better way. © 2015 Wiley Periodicals, Inc. Comput Appl Eng Educ 23:542–555, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21625
Improving Capacitance by Introducing Nitrogen Species and Defects into Graphene
Authors: Tian Ke , Liu Wu‐Jun , Zhang Shun , Zeng Raymond J. , Jiang Hong 
Published: March 2015

AbstractNitrogen‐doped graphene (NG) materials were prepared with different levels of ammonia modification and their capacitive performances were compared. The surface structure, nitrogen species and contents, as well as the defects and disorders of the as‐prepared NG materials were investigated. Electrochemical measurements showed that the capacitance of the NG materials is significantly higher than that of pristine graphene and varies with the ammonia dosage. Graphene modified with 20 mL of ammonia possesses the highest capacitance among all of the materials studied. Further investigation showed that nitrogen species and defects in NG perform pivotal functions in improving capacitance; by contrast, the surface morphology had little influence on the capacitance of the as‐prepared NG materials. Results suggested that adjusting the N1 pyridinic N content is an efficient method for elevating the capacitive performance of NG materials.