bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of the Multivalency of Ultrashort Arg‐Trp‐Based Antimicrobial Peptides (AMP) on Their Antibacterial Activity
Authors: Hoffknecht Barbara C. , Worm Dennis J. , Bobersky Sandra , Prochnow Pascal , Bandow Julia E. , Metzler‐Nolte Nils 
Published: July 2015

AbstractPeptide dendrimers are a class of molecules of high interest in the search for new antibiotics. We used microwave‐assisted, copper(I)‐catalyzed alkyne–azide cycloaddition (CuAAC; “click” chemistry) for the simple and versatile synthesis of a new class of multivalent antimicrobial peptides (AMPs) containing solely arginine and tryptophan residues. To investigate the influence of multivalency on antibacterial activity, short solid‐phase‐ synthesized azide‐modified Arg‐Trp‐containing peptides were “clicked” to three different alkyne‐modified benzene scaffolds to access scaffolds with one, two, or three peptides. The antibacterial activity of 15 new AMPs was investigated by minimal inhibitory concentration (MIC) assays on five different bacterial strains, including a multidrug‐resistant Staphylococcus aureus (MRSA) strain. With ultrashort (2–3 residues) peptides, a clear synergistic effect of the trivalent display was observed, whereas this effect was not apparent with longer peptides. The best candidates showed activities in the low‐micromolar range against Gram‐positive MRSA. Surprisingly, the best activity against Gram‐negative Acinetobacter baumannii was observed with an ultrashort dipeptide on the trivalent scaffold (MIC: 7.5 μM). The hemolytic activity was explored for the three most active peptides. At concentrations ten times the MIC values, <1 % hemolysis of red blood cells was observed.
A Triazolyl‐Pyridine‐Supported CuI Dimer: Tunable Luminescence and Fabrication of Composite Fibers
Authors: Bai Shi‐Qiang , Kai Dan , Ke Karen Lin , Lin Ming , Jiang Lu , Jiang Ying , Young David James , Loh Xian Jun , Li Xu , Hor T. S. Andy 
Published: July 2015

AbstractThe dinuclear complex [Cu2I2(L1)2] (1) (L1=3‐((4‐(pyridin‐2‐yl)‐1H‐1,2,3‐triazol‐1‐yl)methyl)benzonitrile) is characterized by single‐crystal X‐ray diffraction (XRD), powder XRD, IR, photoluminescence spectroscopy, and thermogravimetric analysis. Unlike other related, known copper iodide complexes, it exhibits strong yellow emission in the solid state at both room temperature and 77 K. Showing good compatibility with PMMA, it is blended with the polymer in different weight ratios to prepare luminescent composite fibers.
Rapid water quality change in the Elwha River estuary complex during dam removal
Authors: Foley Melissa M. , Duda Jeffrey J. , Beirne Matthew M. , Paradis Rebecca , Ritchie Andrew , Warrick Jonathan A. 
Published: July 2015

AbstractDam removal in the United States is increasing as a result of structural concerns, sedimentation of reservoirs, and declining riverine ecosystem conditions. The removal of the 32 m Elwha and 64 m Glines Canyon dams from the Elwha River in Washington, U.S.A., was the largest dam removal project in North American history. During the 3 yr of dam removal—from September 2011 to August 2014—more than ten million cubic meters of sediment was eroded from the former reservoirs, transported downstream, and deposited throughout the lower river, river delta, and nearshore waters of the Strait of Juan de Fuca. Water quality data collected in the estuary complex at the mouth of the Elwha River document how conditions in the estuary changed as a result of sediment deposition over the 3 yr the dams were removed. Rapid and large‐scale changes in estuary conditions—including salinity, depth, and turbidity—occurred 1 yr into the dam removal process. Tidal propagation into the estuary ceased following a large sediment deposition event that began in October 2013, resulting in decreased salinity, and increased depth and turbidity in the estuary complex. These changes have persisted in the system through dam removal, significantly altering the structure and functioning of the Elwha River estuary ecosystem.
Biogeochemical and metagenomic analysis of nitrite accumulation in the Gulf of Mexico hypoxic zone
Authors: Bristow Laura A. , Sarode Neha , Cartee John , Caro‐Quintero Alejandro , Thamdrup Bo , Stewart Frank J. 
Published: July 2015

AbstractThe Louisiana Shelf in the Gulf of Mexico experiences recurrent bottom water hypoxia under summertime eutrophic conditions. The onset, maintenance, and breakdown of hypoxia are associated with dynamic microbial biogeochemical cycles. However, the distribution of microbial taxa and metabolisms across Shelf oxygen gradients remains under‐characterized. We combined biogeochemical analyses of nitrogen (N) distributions and metabolic rates with metagenomic and metatranscriptomic analysis of summertime Shelf waters. Samples from an east–west transect during July 2012 revealed an inverse relationship between nitrite and oxygen concentrations, with concentrations exceeding 1 μmol L−1 at ∼ 50% oxygen saturation and reaching 4.6 μmol L−1 at the most oxygen‐depleted sites. Historical data confirms that nitrite accumulation occurs frequently in this region both above and below the hypoxic threshold. Experimental incubations demonstrated a strong decoupling between the two steps of nitrification, with ammonia oxidation proceeding up to 30 times faster than nitrite oxidation under low oxygen. 16S rRNA gene, metagenome, and metatranscriptome sequencing revealed a diverse microbial community, stratified over shallow (< 10 m) depth gradients, with an enrichment of ammonia‐oxidizing Thaumarchaeota genes and transcripts in deeper more oxygen‐depleted layers, and a comparatively low representation of sequences related to nitrite oxidation. A range of factors, including temperature and substrate availability, which may be linked indirectly to bottom water oxygen content, potentially drives decoupling of ammonia and nitrite oxidation on the Louisiana Shelf. Nitrite accumulation in hypoxic zones remains understudied and may have important effects on microbial nitrogen flux, algal dynamics, and production.
The effect of transmitted Er:YAG laser energy through a dental ceramic on different types of resin cements
Authors: Tak Onjen , Sari Tugrul , Arslan Malkoç Meral , Altintas Subutayhan , Usumez Aslihan , Gutknecht Norbert 
Published: July 2015

Background and ObjectiveThe laser debonding procedure of adhesively luted all‐ceramic restorations is based on the ablation of resin cement due to the transmitted laser energy through the ceramic. The purpose of this study was to determine the effect of Er:YAG laser irradiation transmitted through a dental ceramic on five different resin cements.Materials and MethodsFive different resin cements were evaluated in this study: G‐Cem LinkAce, Multilink Automix, Variolink II, Panavia F, and Rely X Unicem U100. Disc shaped resin cement specimens (n = 10) were fabricated for each group. A ceramic disc was placed between the resin cement discs and the tip of the handpiece of Er:YAG laser device. The resin cement discs were irradiated through the ceramic and the volume of the resin cement discs were measured using a micro‐CT system before and after Er:YAG laser irradiation. The volume loss of the resin cement discs was calculated and analyzed with one‐way ANOVA and Tukey–HSD tests.ResultsThe highest volume loss was determined in G‐Cem (1.1 ± 0.6 mm3) and Multilink (1.3 ± 0.1 mm3) (P < 0.05) groups, and the lowest volume loss was determined in Rely X (0.3 ± 0.07 mm3), Variolink (0.4 ± 0.2 mm3), and Panavia (0.6 ± 0.2 mm3) groups (P < 0.05). All resin cements were affected by the laser irradiation resulting in the volume loss of the cement; however, there are significant differences among different resin cements.ConclusionsAll the resin cements tested in this study were effected by the Er:YAG laser irradiation and there were significant differences among the resin cements with regard to ablation volume. Lasers Surg. Med. 47:602–607, 2015. © 2015 Wiley Periodicals, Inc.
Dielectric Relaxation Behavior of a Poly(ethylene carbonate)‐Lithium Bis‐(trifluoromethanesulfonyl) Imide Electrolyte
Authors: Motomatsu Joh , Kodama Hidekazu , Furukawa Takeo , Tominaga Yoichi 
Published: July 2015

A new class of polymer electrolytes, consisting of poly(ethylene carbonate) (PEC) and metal salts, is expected to find application in all‐solid‐state batteries because of its excellent performance as an electrolyte. To study the ion‐conductive mechanism in PEC‐based electrolytes, broadband dielectric spectroscopy is used to analyze the correlation between dielectric relaxation and ionic conduction in PEC‐lithium bis‐(trifluoromethanesulfonyl) imide electrolytes over a broad range of salt concentration (0–150 mol%) at 40 °C. The PEC system has two relaxation modes, α and β, associated respectively with the segmental motion and the local motion of PEC chains. The conductivity increases exponentially with increasing salt concentration, while the α relaxation frequency (fα) decreases with increasing strength (Δεα) at low salt concentrations, whereas in contrast fα increases with Δεα being saturated at high salt concentrations above 10 mol%. It is believed that the mobility of PEC segment at high concentration is enhanced by two factors. The first is that intermolecular interactions decrease, given the existence of many ion pairs and aggregated ions around saturated PEC domains where the dissociated ions are highly concentrated. The second is that intramolecular interactions between CO and CH2 are lowered by the ion–dipole interaction.
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ZPAC is required for normal spermatogenesis in mice
Authors: Zuo Er‐Wei , Yang Xiao‐Gan , Lu Yang‐Qing , Xie Long , Shang Jiang‐Hua , Li Di , Yang Huan , Hu Lin‐Lin , Zhao Hui‐Min , Lu Sheng‐Sheng , Lu Ke‐Huan 
Published: July 2015

SUMMARYThe ubiquitin‐proteasome pathway, involved in genetic recombination and sex‐chromosome silencing during meiosis, plays critical roles in the specification of germ‐line stem cells and the differentiation of gametes from gonocytes. Zygote‐specific proteasome assembly chaperone (ZPAC) is expressed in the early mouse embryo, where it is important for progression of the mouse maternal‐to‐zygotic transition. The role of ZPAC during spermatogenesis in the adult gonads, however, remains unknown. In this study, rapid amplification of cDNA ends was used to determine theZpaccDNA sequence, a 1584‐bp transcript that includes a putative 1122‐bp open reading frame coding for a 373 amino acid protein. Western blot and immunohistochemistry revealed that ZPAC was specifically expressed in gonads. To further dissect the function of ZPAC during spermatogenesis, we employed PiggyBac‐based RNA interference vectors for transgenesis combined with cell transplantation to depleteZpacduring spermatogenesis. This RNAi‐mediate depletion inZpacexpression disrupted normal spermatogenesis from spermatogonial stem cells. Two independent yeast two‐hybrid screens further revealed an interaction between ZPAC and SYCE1. Together, these data suggest that ZPAC is required for normal spermatogenesis in mice.Mol. Reprod. Dev. 82: 747–755, 2015. © 2015 Wiley Periodicals, Inc.
Migration and Social Cohesion: Appraising the Resilience of Place in London
Authors: Hickman Mary J , Mai Nicola 
Published: July 2015

AbstractThis paper is based on research designed to understand how previous immigrations are perceived/experienced and how this informs the contemporary moment of immigration. We explored the actual lived lives and practices of both new immigrants and long‐term settled populations in six places across the UK. We were particularly interested in layered histories of migration, and historically constituted diaspora spaces, that is, the spaces of multiculture encounter in all their specificities and the relevance of this for social intervention policies in the UK.We emphasize the importance of understanding social cohesion and the nation through the formation and (re)formulation of prevailing narratives of belonging, obligation, and identity. These narratives inform the way that social heterogeneity, resulting from social and geographical mobility and the porousness of multiculture spaces of encounter, is managed in different places and at different levels, encompassing the global, the national, and the local dimensions.This paper considers material drawn from in‐depth life narrative interviews in the two sites that we researched in London: Kilburn in the north‐west of the city and Downham in the south‐east. The research aimed to engage with Downham and Kilburn in an exploration of the complexity of ‘cosmopolitan’ London by exploring the way in which the historical experience of migrancy and hybridity (or its lack) can be a factor sustaining (or hindering) social cohesion. Both places are socially and economically deprived areas, but they constitute examples of contrasting responses to contemporary immigration. Copyright © 2015 John Wiley & Sons, Ltd.
Vegetation–Hydrogeomorphology Interactions in a Low‐Energy, Human‐Impacted River
Authors: Gurnell A. M. , Grabowski R. C. 
Published: July 2015

AbstractThe geomorphological dynamics of rivers have been traditionally explained largely by the physical processes of water flow, and sediment erosion and deposition, but the significant role of a third element, vegetation, in driving geomorphological changes has been increasingly highlighted recently. However, few studies have documented how both aquatic and woody riparian plants interact with fluvial processes to induce landform development and initiate channel adjustment. This paper presents analyses of historical maps, recent aerial images and field observations from the River Frome (Dorset, UK), which, as a result of human pressures, has been subject to an increased supply of sand and finer sediment, particularly over the last 50–60 years. Analysis of these information sources indicates that this low‐energy river has adjusted to this delivery of finer sediment by narrowing and increasing its sinuosity. The analysis also indicates that this has been achieved through interactions amongst vegetation, water flow and sediment. Emergent aquatic macrophytes were observed to retain sediment, which leads to the development of submerged shelves that aggrade and become colonized by other plant species to form bars, berms and benches, eventually leading to the extension of river banks into the channel and also the formation of islands. Where woody riparian vegetation is well developed, complex geomorphic changes were observed, with fine sediment being absorbed into a diverse mosaic of geomorphic features initiated by living trees and large wood. These observations underline the importance of vegetation for the geomorphic dynamics and adjustment of lowland, low‐energy rivers and its potential for inclusion in the development of sustainable, process‐based river management and restoration strategies. Copyright © 2015 John Wiley & Sons, Ltd.
Awakening a dialogue: A critical race theory analysis of U. S. nature of science research from 1967 to 2013
Authors: Walls Leon 
Published: July 2015

AbstractAs the nation's K‐12 classrooms become increasingly more racially, culturally, and linguistically diverse, it is incumbent upon the science community to seize opportunities to attend to the rhetoric of reform, namely to enhance scientific literacy for all students. Using Critical Race Theory (CRT) as a framework, this study examined 112 nature of science (NOS) research peer‐reviewed studies conducted in the U. S. from (1967 to 2013). Results suggests that while White participants are being represented in the NOS research, Black, Latino, Native American and other people of color, were found to be disproportionally excluded as participants. Implications of excluding these individuals are explored and suggestions for making NOS research more equitable are discussed. © 2015 Wiley Periodicals, Inc. J Res Sci Teach 53: 1546–1570, 2016
Bayesian co‐clustering
Authors: Domeniconi Carlotta , Laskey Kathryn 
Published: July 2015

Co‐clustering means simultaneously identifying natural clusters in different kinds of objects. Examples include simultaneously clustering customers and products for a recommender application; simultaneously clustering proteins and molecules in microbiology; or simultaneously clustering documents and words in a text mining application. Important insights into a problem can be gained by understanding the interactions between clusters for the different kinds of objects. This paper considers Bayesian models for co‐clustering. The Bayesian approach begins by developing a model for the data generating process, and inverting that model through Bayesian inference to infer cluster membership, learn characteristics of the clusters, and fill in missing observations. We consider a basic Bayesian clustering model and several extensions to the model. Experimental evaluations and comparisons among the clustering methods are presented. WIREs Comput Stat 2015, 7:347–356. doi: 10.1002/wics.1359This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Bayesian Methods and Theory
Statistical Learning and Exploratory Methods of the Data Sciences > Clustering and Classification
Statistical and Graphical Methods of Data Analysis > Nonparametric Methods
Identifying Perceived Neighborhood Stressors Across Diverse Communities in New York City
Authors: Shmool Jessie L. C. , Yonas Michael A. , Newman Ogonnaya Dotson , Kubzansky Laura D. , Joseph Evelyn , Parks Ana , Callaway Charles , Chubb Lauren G. , Shepard Peggy , Clougherty Jane E. 
Published: July 2015

AbstractThere is growing interest in the role of psychosocial stress in health disparities. Identifying which social stressors are most important to community residents is critical for accurately incorporating stressor exposures into health research. Using a community‐academic partnered approach, we designed a multi‐community study across the five boroughs of New York City to characterize resident perceptions of key neighborhood stressors. We conducted 14 community focus groups; two to three in each borough, with one adolescent group and one Spanish‐speaking group per borough. We then used systematic content analysis and participant ranking data to describe prominent neighborhood stressors and identify dominant themes. Three inter‐related themes regarding the social and structural sources of stressful experiences were most commonly identified across neighborhoods: (1) physical disorder and perceived neglect, (2) harassment by police and perceived safety and (3) gentrification and racial discrimination. Our findings suggest that multiple sources of distress, including social, political, physical and economic factors, should be considered when investigating health effects of community stressor exposures and psychological distress. Community expertise is essential for comprehensively characterizing the range of neighborhood stressors that may be implicated in psychosocial exposure pathways.
Mitochondrial SSRs and their utility in distinguishing wild species, CMS lines and maintainer lines in pigeonpea (Cajanus cajan L.)
Authors: Khera Pawan , Saxena Rachit , Sameerkumar C. V. , Saxena Kulbhushan , Varshney Rajeev K. 
Published: July 2015

AbstractAnalysis of the pigeonpea mitochondrial genome sequence identified 25 SSRs. Mononucleotide SSR motifs were the most abundant repeats followed by dinucleotide and trinucleotide repeats. Primer pairs could be designed for 24 SSRs, 23 of which were polymorphic amongst the 22 genotypes consisting of cytoplasmic male sterile (CMS or A) line, maintainer or B line and wild Cajanus species representing six different CMS systems viz., A1, A2, A4, A5, A6 and A8. These markers amplified a total of 107 alleles ranging from 2 to 10 with an average of 4.65 alleles per locus. The polymorphic information content for these markers ranged from 0.09 to 0.84 with an average of 0.52 per marker. Hence, the present study adds a novel set of 24 mitochondrial SSR markers to the markers repository in pigeonpea, which would be useful to distinguish the genotypes based on mitochondrial genome types in evolutionary and phylogenetic studies.
Biodiesel Production from Mustard Emulsion by a Combined Destabilization/Adsorption Process
Authors: Tabtabaei Solmaz , Boocock David G. B. , Diosady Levente L. 
Published: July 2015

AbstractTetrahydrofuran, added to the oil‐in‐water emulsions formed by the aqueous processing of yellow mustard flour, produced oil/water/THF miscellas containing 1–2 % water. The high water content prevented the direct conversion of the system to fatty acid methyl esters (FAME) through a single‐phase base‐catalyzed transmethylation process. Dehydration of these miscellas by adsorption on 4A molecular sieves at room temperature using either batch or continuous fixed‐bed systems successfully reduced the water content to the quality standards needed for biodiesel feedstock (0.3 %). Equilibrium adsorption studies for the uptake of water from oil/THF/water miscella phases at room temperature allowed quantitative comparison of the water adsorption capacity based on the oil and THF concentrations of the miscellas. Batch contact was used to investigate the dominant parameters affecting the uptake of water including miscella composition, adsorbent dose and contact time. The adsorption of the water was strongly dependent on adsorbent dose and miscella oil concentrations. The regeneration of molecular sieves by heating under nitrogen at reduced pressure for 6 h at 275 °C resulted in incomplete desorption of miscella components. The adsorption breakthrough curves in terms of flow rates, initial water and oil miscella concentrations were determined. The dehydrated miscella phases were reacted with methanol in a single‐phase base‐catalyzed transmethylation process with high yields (99.3 wt%) to FAME. The resulting FAME met the ASTM international standard in terms of total glycerol content and acid number.