bluuebunny/crossref_metadata_2025 huggingface dataset:
Aldehyde and Ketone Synthesis by P450‐Catalyzed Oxidative Deamination of Alkyl Azides
Authors: Giovani Simone , Alwaseem Hanan , Fasan Rudi
Published: July 2016

Heme‐containing proteins have recently attracted increasing attention for their ability to promote synthetically valuable transformations not found in nature. Following the recent discovery that engineered variants of myoglobin can catalyze the direct conversion of organic azides into aldehydes, we investigated the azide oxidative deamination reactivity of a variety of hemoproteins featuring different heme coordination environments. Our studies show that although several heme‐containing enzymes possess basal activity in this reaction, an engineered variant of the bacterial cytochrome P450 CYP102A1 constitutes a particularly efficient biocatalyst for promoting this transformation, and it exhibits a broad substrate scope along with high catalytic activity (up to 11 300 turnovers), excellent chemoselectivity, and enhanced reactivity toward secondary alkyl azides to yield ketones. Mechanistic studies and Michaelis–Menten analyses provided insight into the mechanism of the reaction and the impact of active‐site mutations on the catalytic properties of the P450. Altogether, these studies demonstrate that engineered P450 variants represent promising biocatalysts for the synthesis of aryl aldehydes and ketones through the oxidative deamination of alkyl azides under mild reaction conditions.
Layered Li1.3Mn0.58Ni0.12Co0.11O2+δ Cathode Material for Lithium‐Ion Batteries with High Reversible Capacity
Authors: Deng Ya‐Ping , Fu Fang , Wu Zhen‐Guo , Zhang Tao , Yin Zu‐Wei , Zhang Shao‐Jian , Li Jun‐Tao , Huang Ling , Sun Shi‐Gang
Published: July 2016

Layered Li1.3Mn0.58Ni0.12Co0.11O2+δ, a solid solution of 0.53 Li2MnO3⋅0.47 LiMn0.4Ni0.3Co0.3O2, has been successfully synthesized by using an improved solvothermal strategy and used as the cathode material of a Li‐ion battery. The pure phase of the layered structure is characterized by using X‐ray diffraction and Raman spectroscopy. Electrochemical tests demonstrate that as‐synthesized layered Li1.3Mn0.58Ni0.12Co0.11O2+δ exhibits high discharge capacities of 349.4, 322.4, 304.6, and 291.7 mAh g−1 at 0.1, 0.2, 0.5, and 1 C rates, respectively. Such high reversible capacities could be ascribed to the enrichment of oxygen in the materials, which was evidenced clearly by a potential plateau below 3.0 V in the discharge process and originated form the electrochemical oxygen reduction.
Analysis of multiblock datasets using ComDim: Overview and extension to the analysis of (K + 1) datasets
Authors: El Ghaziri Angélina , Cariou Véronique , Rutledge Douglas N. , Qannari El Mostafa
Published: July 2016

ComDim analysis was designed to assess the relationships between individuals and variables within a multiblock setting where several variables, organized in blocks, are measured on the same individuals. An overview of this method is presented together with some of its properties. Furthermore, we discuss a new extension of the method of analysis to the case of (K+1) datasets. More precisely, the aim is to explore the relationships between a response dataset and K other datasets. An illustration of this latter strategy of analysis on the basis of a case study involving Time Domain ‐ Nuclear Magnetic Resonance data is outlined and the outcomes are compared with those of Multiblock Partial Least Squares regression.
Introducing a Hydrogen‐Bond Donor into a Weakly Nucleophilic Brønsted Base: Alkali Metal Hexamethyldisilazides (MHMDS, M=Li, Na, K, Rb and Cs) with Ammonia
Authors: Neufeld Roman , Michel Reent , Herbst‐Irmer Regine , Schöne Ralf , Stalke Dietmar
Published: July 2016

Alkali metal 1,1,1,3,3,3‐hexamethyldisilazide (MHMDSs) are one of the most utilised weakly nucleophilic Brønsted bases in synthetic chemistry and especially in natural product synthesis. Like lithium organics, they aggregate depending on the employed donor solvents. Thus, they show different reactivity and selectivity as a function of their aggregation and solvation state. To date, monomeric LiHMDS with monodentate donor bases was only characterised in solution. Since the first preparation of LiHMDS in 1959 by Wannagat and Niederprüm, all efforts to crystallise monomeric LiHMDS in the absence of chelating ligands failed. Herein, we present ammonia adducts of LiHMDS, NaHMDS, KHMDS, RbHMDS and CsHMDS with unprecedented aggregation motifs: 1) The hitherto missing monomeric key compound in the LiHMDS aggregation architectures. Monomeric crystal structures of trisolvated LiHMDS (1) and NaHMDS (2), showing unique intermolecular hydrogen bonds, 2) the unprecedented tetrasolvated KHMDS (3) and RbHMDS (4) dimers and 3) the disolvated CsHMDS (5) dimer with very close intermolecular Si−CH3⋅⋅⋅Cs s‐block “agostic” interactions have been prepared and characterised by single‐crystal X‐ray structure analysis.
Enantioselective Syntheses of Lignin Models: An Efficient Synthesis of β‐O‐4 Dimers and Trimers by Using the Evans Chiral Auxiliary
Authors: Njiojob Costyl N. , Bozell Joseph J. , Long Brian K. , Elder Thomas , Key Rebecca E. , Hartwig William T.
Published: July 2016

We describe an efficient five‐step, enantioselective synthesis of (R,R)‐ and (S,S)‐lignin dimer models possessing a β‐O‐4 linkage, by using the Evans chiral aldol reaction as a key step. Mitsunobu inversion of the (R,R)‐ or (S,S)‐isomers generates the corresponding (R,S)‐ and (S,R)‐diastereomers. We further extend this approach to the enantioselective synthesis of a lignin trimer model. These lignin models are synthesized with excellent ee (>99 %) and high overall yields. The lignin dimer models can be scaled up to provide multigram quantities that are not attainable by using previous methodologies. These lignin models will be useful in degradation studies probing the selectivity of enzymatic, microbial, and chemical processes that deconstruct lignin.
Chemical Platform for the Preparation of Synthetic Orally Active Peptidomimetics with Hemoregulating Activity
Authors: Deigin Vladislav , Ksenofontova Olga , Khrushchev Alexey , Yatskin Oleg , Goryacheva Alexandra , Ivanov Vadim
Published: July 2016

A novel chemical platform based on branched piperazine‐2,5‐dione derivatives (2,5‐diketopiperazines) for creating orally available biologically active peptidomimetics has been developed. The platform includes a diketopiperazine scaffold with “built‐in” functionally active peptide fragments covalently attached via linkers. The concept was applied to two hemostimulatory drugs, the dipeptide thymogen (GluTrp) and the tripeptide stemokin (IleGluTrp). Preparation of a series of respective derivatives is described. Of the five synthesized analogues, three demonstrated high hemostimulatory activity in vivo on intact mice and on ex vivo irradiated bone marrow cells. Prospects of further development of the concept are discussed.
Tobacco assessment in completed lung cancer treatment trials
Authors: Peters Erica N. , Warren Graham W. , Sloan Jeff A. , Marshall James R.
Published: July 2016

An effort over 3 years to conduct a data pooling project regarding the association between smoking and lung cancer treatment outcomes has shown that, of 32 completed studies of lung cancer treatments in 1 National Cancer Institute Cooperative Group, only a minority have usable data concerning smoking‐related variables. Clinical trials research is needed to inform patients with cancer and their physicians about the impact of smoking, and how smoking cessation may affect the course of their disease.
Nanomaterial‐Based Soft Electronics for Healthcare Applications
Authors: Choi Changsoon , Choi Moon Kee , Hyeon Taeghwan , Kim Dae‐Hyeong
Published: July 2016

Soft electronic devices, particularly for healthcare applications, have been intensively studied over the past decade owing to their unique advantages over conventional rigid electronics. These advantages include conformal contacts on target tissues such as the skin, heart, and brain along with a high deformability that minimizes unwanted inflammatory responses. To achieve mechanically soft but multifunctional high performance electronics for wearable and implantable biomedical devices, several strategies have been employed including designed assembly of high quality nanomaterials, the combination of unconventional manufacturing processes with existing microprocessing technologies, new device designs with deformable structures, and disease‐specific system‐level integration of diverse soft electronics. In this Focus Review, we summarize recent advances in soft electronic devices for healthcare applications. More specifically, we describe assembly methods for various nanomaterials, new device designs and integration strategies, their applications to textile‐based and skin‐attached wearable electronics, and their incorporation in fully and/or minimally invasive medical devices. Finally, this review concludes with a brief description on the future direction of healthcare applications using nanomaterial‐based soft bioelectronics.
Net demand prediction for power systems by a new neural network‐based forecasting engine
Authors: Abedinia Oveis , Amjady Nima
Published: July 2016

Integration of renewable generations, such as wind and photovoltaic, into electrical power systems is rapidly growing throughout the world. Stochastic and variable nature of these resources makes some operational challenges to power systems. The most effective way to tackle these challenges is short‐term prediction of their available powers. Despite various developed methods to forecast generation of renewable resources, still they have large errors, which may lead to under/over‐commitment of conventional generators in power systems. Prediction of net demand (ND), defined as electrical load minus renewable generations, can provide useful information for accurate scheduling of conventional generators. In this article, characteristics of the time series of electric load, renewable generations and ND are analyzed, and a new hybrid prediction strategy is presented for direct prediction of ND. The training mechanism of the proposed forecasting engine is composed of a new stochastic search method and Levenberg–Marquardt learning algorithm based on an iterative procedure and greedy search. The suggested prediction strategy is tested on different real‐world power systems and its obtained results are compared with the results of several other forecast methods and published literature figures. These comparisons confirm the validity of the developed forecasting strategy. © 2016 Wiley Periodicals, Inc. Complexity 21: 296–308, 2016
Networks metrics and ball possession in professional football
Authors: Gama José , Dias Gonçalo , Couceiro Micael , Sousa Tiago , Vaz Vasco
Published: July 2016

This study aimed to verify the network of interactions resulting from the collective behavior of professional football teams and the influence of ball possession. A dataset of 30 matches of one highly successful team from the Portuguese Premier League, season 2010/2011, was considered. From these 30 matches, 13,958 passes (e.g., 11,127 successfully passes and 2831 unsuccessfully passes) and 7583 collective offensive actions were analysed. The data were analysed using Node XL Template that allows to characterize networks and team activity profiles. The results showed that football players' interactions tended to occur, preferentially, during the offensive phase, wherein the network of contacts was mainly organised in the central and lateral areas of the field. We concluded that the ball possession during a football match endows the team with a larger domain in terms of game actions. Moreover, the results of this study also allow concluding that the ball possession does not significantly influence the final outcome of the game. This study has practical implications for coaches, since it provides a multidimensional analysis of the football match (e.g., networks and ball possession) and offers relevant insights on how creative and organizing individuals might act to orchestrate team strategies. © 2016 Wiley Periodicals, Inc. Complexity 21: 342–354, 2016
Manganese‐Substituted Polyoxometalate as an Effective Shuttle Redox Mediator in Z‐Scheme Water Splitting under Visible Light
Authors: Tsuji Kohei , Tomita Osamu , Higashi Masanobu , Abe Ryu
Published: July 2016

In the present study, a polyoxometalate is for the first time applied as a shuttle redox in two‐step (Z‐Scheme) photocatalytic water splitting. Photocatalytic H2 evolution using a Mn‐substituted polyoxometalate [SiW11O39MnII(H2O)]6− as an electron donor proceeded over a Ru‐loaded SrTiO3:Rh photocatalyst under visible light with relatively high selectivity, accompanied by the stoichiometric production of its oxidized form [SiW11O39MnIII(H2O)]5−. Photocatalytic O2 evolution using the oxidized [SiW11O39MnIII(H2O)]5− as an electron acceptor proceeded over PtOx‐loaded WO3 photocatalyst under visible light with relatively high quantum efficiency and selectivity, whereas the loading of effective PtOx cocatalyst was necessary to facilitate the reduction of polyoxometalate. Finally, a two‐step water splitting into H2 and O2 was demonstrated under visible light using the couple of Mn‐substituted polyoxometalate as shuttle redox between Ru/SrTiO3:Rh and PtOx/WO3 photocatalysts, under mildly acidic conditions with pH≈4.5.
Hybrid channel gain prioritized access‐aware cell association with interference mitigation in LTE‐Advanced HetNets
Authors: Gadam M.A. , Ng Chee Kyun , Nordin Nor Kamariah , Sali Aduwati , Hashim Fazirulhisyam
Published: July 2016

LTE‐Advanced heterogeneous networks deployment is meant to address the increasing demand for quality of service, high data rates and coverage extension. Load balancing is among the primary challenges, especially when the user equipments (UEs) associate with diverse transmission power network tiers using received signal strength. The low‐power network tier's spectrum will be underutilized, and UEs associated with them will be inflicted by interference from the high‐power network tier. The proposed hybrid channel gain prioritized access (HCGPA)‐aware cell association scheme stresses the importance of combined metrics with interference mitigation to simultaneously achieve load balancing and enhance performance among the network tiers. The high‐priority UEs associate with the tier that gives the maximum channel gain being higher than a given threshold. While the low‐priority UEs association is based on the maximum joint metrics (channel gain, channel access probabilities of low‐priority UEs and high‐priority UEs). The HCGPA scheme has 1.72 times the number of UEs connected to low‐power networks, 8% better load balancing fairness, compared with the conventional reference signal receive power and RSRP + 6 dB bias cell associations. Although the susceptibility of HCGPA to interference led to the poor signal to interference to noise ratio (SINR) performance of the cell‐edge UEs, the cell‐centre UEs exhibited the best spectral efficiency performance. Copyright © 2016 John Wiley & Sons, Ltd.
Manganese enrichments near a large gas‐hydrate and cold‐seep field: a record of past redox and sedimentation events
Authors: Ingram Wesley C. , Meyers Stephen R. , Shen Zhizhang , Xu Huifang , Martens Christopher S.
Published: July 2016

The spatial distribution, mineralogy, and origin of manganese enrichments surrounding a large gas hydrate and cold seep field (Mississippi Canyon 118, Gulf of Mexico) are investigated in this study, to better constrain their biogeochemical context in deep‐sea sediments and to assess how gas hydrates may alter such records. Manganese depth profiles from 10 sediment cores, documented using centimetre‐scale X‐ray fluorescence core scanning, display highly‐enriched 1 to 10 cm thick layers. These manganese‐rich layers are more numerous, but of lower concentration, in close proximity to the field, and show no consistent relationship with sedimentology (clay vs. carbonate content) or the established chronostratigraphic framework at the site. X‐ray diffraction and sequential dissolution procedures indicate that the manganese enrichments are authigenic carbonates, which formed along a palaeo redox boundary during periods of prolonged steady‐state conditions. The hypothesis that spatial heterogeneity of this manganese record is linked to the nearby gas hydrate and cold seep field, by influencing redox conditions and/or sedimentation processes, is investigated here. Results are consistent with more frequent interruption of steady‐state sedimentation in closer proximity to the salt‐tectonic induced bathymetric mound, which contains the active cold seeps and gas hydrate deposits. Thus, spatial mapping of manganese enrichment horizons provides a tool to reconstruct sedimentation surrounding these volatile sea bed features, yielding a measure of past activity of gas hydrates and cold seeps.
Diabetic nephropathy in type 1 diabetes: a review of early natural history, pathogenesis, and diagnosis
Authors: Papadopoulou‐Marketou Nektaria , Chrousos George P. , Kanaka‐Gantenbein Christina
Published: July 2016

Diabetic nephropathy constitutes a devastating complication in patients with type 1 diabetes mellitus, and its diagnosis is traditionally based on microalbuminuria. The aim of this review is to update through the medical literature the suggested early natural course of diabetic nephropathy, the theories behind the pathways of its pathogenesis, and its diagnosis. Poor glycemic control, dyslipidemia, smoking, advanced glycation end products, and environmental and genetic clues play an important role in the development of diabetic nephropathy. Microalbuminuria has been traditionally considered as a primary early marker of microvascular complication unraveling the risk for progress to the advanced stages of chronic kidney disease, but because of our inability to make an early diagnosis of diabetic nephropathy in young patients as well as nonalbuminuric diabetic nephropathy, recently, other additional markers of renal injury like serum and urinary neutrophil gelatinase–associated lipocalin, chitinase‐3–like protein 1, cystatin C, and plasma growth differentiation factor 15 have been proposed to unmask early renal dysfunction, even before microalbuminuria supervenes. Copyright © 2016 John Wiley & Sons, Ltd.
Relative importance of climate and mountain pine beetle outbreaks on the occurrence of large wildfires in the westernUSA
Authors: Mietkiewicz Nathan , Kulakowski Dominik
Published: July 2016

Extensive outbreaks of bark beetles have killed trees across millions of hectares of forests and woodlands in western North America. These outbreaks have led to spirited scientific, public, and policy debates about consequential increases in fire risk, especially in the wildland–urban interface (WUI), where homes and communities are at particular risk from wildfires. At the same time, large wildfires have become more frequent across this region. Widespread expectations that outbreaks increase extent, severity, and/or frequency of wildfires are based partly on visible and dramatic changes in foliar moisture content and other fuel properties following outbreaks, as well as associated modeling projections. A competing explanation is that increasing wildfires are driven primarily by climatic extremes, which are becoming more common with climate change. However, the relative importance of bark beetle outbreaks vs. climate on fire occurrence has not been empirically examined across very large areas and remains poorly understood. The most extensive outbreaks of tree‐killing insects across the western United States have been of mountain pine beetle (MPB;Dendroctonus ponderosae), which have killed trees over >650,000 km2, mostly in forests dominated by lodgepole pine (Pinus contorta). We show that outbreaks ofMPBin lodgepole pine forests of the western United States have been less important than climatic variability for the occurrence of large fires over the past 29 years. In lodgepole pine forests in general, as well as those in theWUI, occurrence of large fires was determined primarily by current and antecedent high temperatures and low precipitation but was unaffected by preceding outbreaks. Trends of increasing co‐occurrence of wildfires and outbreaks are due to a common climatic driver rather than interactions between these disturbances. Reducing wildfire risk hinges on addressing the underlying climatic drivers rather than treating beetle‐affected forests.
Limiting inbreeding in disjunct and isolated populations of a woody shrub
Authors: Sampson Jane F. , Byrne Margaret , Gibson Neil , Yates Colin
Published: July 2016

Pollen movements and mating patterns are key features that influence population genetic structure. When gene flow is low, small populations are prone to increased genetic drift and inbreeding, but naturally disjunct species may have features that reduce inbreeding and contribute to their persistence despite genetic isolation. Using microsatellite loci, we investigated outcrossing levels, family mating parameters, pollen dispersal, and spatial genetic structure in three populations of Hakea oldfieldii, a fire‐sensitive shrub with naturally disjunct, isolated populations prone to reduction in size and extinction following fires. We mapped and genotyped a sample of 102 plants from a large population, and all plants from two smaller populations (28 and 20 individuals), and genotyped 158–210 progeny from each population. We found high outcrossing despite the possibility of geitonogamous pollination, small amounts of biparental inbreeding, a limited number of successful pollen parents within populations, and significant correlated paternity. The number of pollen parents for each seed parent was moderate. There was low but significant spatial genetic structure up to 10 m around plants, but the majority of successful pollen came from outside this area including substantial proportions from distant plants within populations. Seed production varied among seven populations investigated but was not correlated with census population size. We suggest there may be a mechanism to prevent self‐pollination in H. oldfieldii and that high outcrossing and pollen dispersal within populations would promote genetic diversity among the relatively small amount of seed stored in the canopy. These features of the mating system would contribute to the persistence of genetically isolated populations prone to fluctuations in size.
Factors influencing the survival of outmigrating juvenile salmonids through multiple dam passages: an individual‐based approach
Authors: Elder Timothy , Woodley Christa M. , Weiland Mark A. , Strecker Angela L.
Published: July 2016

Substantial declines of Pacific salmon populations have occurred over the past several decades related to large‐scale anthropogenic and climatic changes in freshwater and marine environments. In the Columbia River Basin, migrating juvenile salmonids may pass as many as eight large‐scale hydropower projects before reaching the ocean; however, the cumulative effects of multiple dam passages are largely unknown. Using acoustic transmitters and an extensive system of hydrophone arrays in the Lower Columbia River, we calculated the survival of yearling Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) passing one, two, or three dams. We applied a unique index of biological characteristics and environmental exposures, experienced by each fish individually as it migrated downstream, in order to examine which factors most influence salmonid survival. High outflow volumes led to involuntary spill in 2011 and created an environment of supersaturated dissolved gas concentrations. In this environment, migrating smolt survival was strongly influenced by barometric pressure, fish velocity, and water temperature. The effect of these variables on survival was compounded by multiple dam passages compared to fish passing a single dam. Despite spatial isolation between dams in the Lower Columbia River hydrosystem, migrating smolt appear to experience cumulative effects akin to a press disturbance. In general, Chinook salmon and steelhead respond similarly in terms of survival rates and responses to altered environmental conditions. Management actions that limit dissolved gas concentrations in years of high flow will benefit migrating salmonids at this life stage.
Life history evolution and cellular mechanisms associated with increased size in high‐altitude Drosophila
Authors: Lack Justin B. , Yassin Amir , Sprengelmeyer Quentin D. , Johanning Evan J. , David Jean R. , Pool John E.
Published: July 2016

Understanding the physiological and genetic basis of growth and body size variation has wide‐ranging implications, from cancer and metabolic disease to the genetics of complex traits. We examined the evolution of body and wing size in high‐altitude Drosophila melanogaster from Ethiopia, flies with larger size than any previously known population. Specifically, we sought to identify life history characteristics and cellular mechanisms that may have facilitated size evolution. We found that the large‐bodied Ethiopian flies laid significantly fewer but larger eggs relative to lowland, smaller‐bodied Zambian flies. The highland flies were found to achieve larger size in a similar developmental period, potentially aided by a reproductive strategy favoring greater provisioning of fewer offspring. At the cellular level, cell proliferation was a strong contributor to wing size evolution, but both thorax and wing size increases involved important changes in cell size. Nuclear size measurements were consistent with elevated somatic ploidy as an important mechanism of body size evolution. We discuss the significance of these results for the genetic basis of evolutionary changes in body and wing size in Ethiopian D. melanogaster.
Ode to Ehrlich and Raven or how herbivorous insects might drive plant speciation
Authors: Marquis Robert J. , Salazar Diego , Baer Christina , Reinhardt Jason , Priest Galen , Barnett Kirk
Published: July 2016

Fifty years ago, Ehrlich and Raven proposed that insect herbivores have driven much of plant speciation, particularly at tropical latitudes. There have been no explicit tests of their hypotheses. Indeed there were no proposed mechanisms either at the time or since by which herbivores might generate new plant species. Here we outline two main classes of mechanisms, prezygotic and postzygotic, with a number of scenarios in each by which herbivore‐driven changes in host plant secondary chemistry might lead to new plant lineage production. The former apply mainly to a sympatric model of speciation while the latter apply to a parapatric or allopatric model. Our review suggests that the steps of each mechanism are known to occur individually in many different systems, but no scenario has been thoroughly investigated in any one system. Nevertheless, studies of Dalechampia and its herbivores and pollinators, and patterns of defense tradeoffs in trees on different soil types in the Peruvian Amazon provide evidence consistent with the original hypotheses of Ehrlich and Raven. For herbivores to drive sympatric speciation, our findings suggest that interactions with both their herbivores and their pollinators should be considered. In contrast, herbivores may drive speciation allopatrically without any influence by pollinators. Finally, there is evidence that these mechanisms are more likely to occur at low latitudes and thus more likely to produce new species in the tropics. The mechanisms we outline provide a predictive framework for further study of the general role that herbivores play in diversification of their host plants.
Hierarchical filters determine community assembly of urban species pools
Authors: Aronson Myla F. J. , Nilon Charles H. , Lepczyk Christopher A. , Parker Tommy S. , Warren Paige S. , Cilliers Sarel S. , Goddard Mark A. , Hahs Amy K. , Herzog Cecilia , Katti Madhusudan , La Sorte Frank A. , Williams Nicholas S. G. , Zipperer Wayne
Published: July 2016

The majority of humanity now lives in cities or towns, with this proportion expected to continue increasing for the foreseeable future. As novel ecosystems, urban areas offer an ideal opportunity to examine multi‐scalar processes involved in community assembly as well as the role of human activities in modulating environmental drivers of biodiversity. Although ecologists have made great strides in recent decades at documenting ecological relationships in urban areas, much remains unknown, and we still need to identify the major ecological factors, aside from habitat loss, behind the persistence or extinction of species and guilds of species in cities. Given this paucity of knowledge, there is an immediate need to facilitate collaborative, interdisciplinary research on the patterns and drivers of biodiversity in cities at multiple spatial scales. In this review, we introduce a new conceptual framework for understanding the filtering processes that mold diversity of urban floras and faunas. We hypothesize that the following hierarchical series of filters influence species distributions in cities: (1) regional climatic and biogeographical factors; (2) human facilitation; (3) urban form and development history; (4) socioeconomic and cultural factors; and (5) species interactions. In addition to these filters, life history and functional traits of species are important in determining community assembly and act at multiple spatial scales. Using these filters as a conceptual framework can help frame future research needed to elucidate processes of community assembly in urban areas. Understanding how humans influence community structure and processes will aid in the management, design, and planning of our cities to best support biodiversity.
Vagal innervation is required for the formation of tertiary lymphoid tissue in colitis
Authors: Olivier Brenda J. , Cailotto Cathy , van der Vliet Jan , Knippenberg Marlene , Greuter Mascha J. , Hilbers Francisca W. , Konijn Tanja , te Velde Anje A. , Nolte Martijn A. , Boeckxstaens Guy E. , de Jonge Wouter J. , Mebius Reina E.
Published: July 2016

Tertiary lymphoid tissue (TLT) is lymphoid tissue that forms in adult life as a result of chronic inflammation in a tissue or organ. TLT has been shown to form in a variety of chronic inflammatory diseases, though it is not clear if and how TLT develops in the inflamed colon during inflammatory bowel disease. Here, we show that TLT develops as newly formed lymphoid tissue in the colon following dextran sulphate sodium induced colitis in C57BL/6 mice, where it can be distinguished from the preexisting colonic patches and solitary intestinal lymphoid tissue. TLT in the inflamed colon develops following the expression of lymphoid tissue‐inducing chemokines and adhesion molecules, such as CXCL13 and VCAM‐1, respectively, which are produced by stromal organizer cells. Surprisingly, this process of TLT formation was independent of the lymphotoxin signaling pathway, but rather under neuronal control, as we demonstrate that selective surgical ablation of vagus nerve innervation inhibits CXCL13 expression and abrogates TLT formation without affecting colitis. Sympathetic neuron denervation does not affect TLT formation. Hence, we reveal that inflammation in the colon induces the formation of TLT, which is controlled by innervation through the vagus nerve.
Enhancement of carbon dioxide capture by amine‐modified rice husk mesoporous material
Authors: Boonpoke Anusorn , Chiarakorn Siriluk , Laosiripojana Navadol , Chidthaisong Amnat
Published: July 2016

Carbon dioxide capture and sequestration (CCS) has become a promising mitigation measure to reduce carbon dioxide (CO2) emissions from large stationary point sources. The CO2 capture process is the core limitation in terms of operating costs and energy consumption. To address this problem, this work aims to produce low cost solid sorbents for capturing CO2. Rice husk was used as a silica source for Mobil Composition of Matter No. 41 (MCM‐41) synthesis (called R‐MCM‐41). To enhance the CO2 adsorption performance at a high temperature, polyethyleneimine (PEI), monoethanolamine (MEA), and aniline (ANL) were applied as modification reagents onto the R‐MCM‐41 surface. The adsorption test was conducted by using an adsorption column. The results indicated that the adsorption capacity of R‐MCM‐41 decreased with an increase in adsorption temperature. However, amine modification can enhance the adsorption capacity at high adsorption temperatures. Out of all the materials tested, the R‐MCM‐41 impregnated with 50 wt % of PEI provided the highest adsorption capacity at 1.70 mmol g−1. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1716–1723, 2016
Can channel banks be the dominant source of fine sediment in a UK river?: an example using 137Cs to interpret sediment yield and sediment source
Authors: Pulley Simon , Foster Ian
Published: July 2016

Cultivated fields have been shown to be the dominant sources of sediment in almost all investigated UK catchments, typically contributing 85 to 95% of sediment inputs. As a result, most catchment management strategies are directed towards mitigating these sediment inputs. However, in many regions of the UK such as the Nene basin there is a paucity of sediment provenance data. This study used the caesium‐137 (137Cs) inventories of lake and floodplain cores as well as the 137Cs activities of present day sediment to determine sediment provenance. Sediment yields were also reconstructed in a small lake catchment.

Low 137Cs inventories were present in the lake and floodplain cores in comparison to the reference inventory and inventories in cores from other UK catchments. Caesium‐137 activities in the present day sediments were low; falling close to those found in the channel bank catchment samples. It was estimated that 60 to 100% of the sediment in the Nene originated from channel banks.

Pre‐1963 sediment yields were approximately 11.2 t km−2 yr−1 and post‐1963 was approximately 11.9 t km−2 yr−1. The lack of increased sediment yield post‐1963 and low sediment yield is unusual for a UK catchment (where a yield of 28 to 51 t km−2 yr−1 is typical for a lowland agricultural catchment), but is explained by the low predicted contribution of sediment from agricultural topsoils. The high channel bank contribution is likely caused by the river being starved of sediment from topsoils, increasing its capacity to entrain bank material.

The good agreement between the results derived using cores and recently transported sediments, highlight the reliability of 137Cs when tracing sediment sources. However, care should be taken to assess the potential impacts of sediment particle size, sediment focusing in lakes and the possible remobilization of 137Cs from sedimentary deposits. Copyright © 2016 John Wiley & Sons, Ltd.
Using the Weibull distribution to improve the description of riverine wood loads
Authors: Stout Justin C. , Rutherfurd Ian , Grove James , Webb J. Angus , Kitchingman Adrian , Tonkin Zeb
Published: July 2016

Reporting uncertainty in environmental measurements and estimates is important for cross‐comparison and inter‐comparison of sites and other spatial units. One such measure is the load of large in‐stream wood in river systems. In this paper we propose the use of the Weibull distribution to describe the central tendency and variability of wood loads along a river reach. We illustrate the link between the average wood load and the central tendency or scale parameter of the Weibull distribution. The shape of the Weibull distribution is strongly related to the ability of rivers to transport and rearrange the wood in a reach. We use six Victorian rivers to test the fit of the Weibull distribution, showing that the Weibull is a useful and flexible distribution that provides common reporting metrics useful for future studies. Using common reporting metrics provides a stronger tool for comparisons of wood loads between rivers and with reaches. Copyright © 2016 John Wiley & Sons, Ltd.
Spheroidal weathering of granite porphyry with well‐developed columnar joints by oxidation, iron precipitation, and rindlet exfoliation
Authors: Hirata Yasuto , Chigira Masahiro , Chen Youqing
Published: July 2016

Spheroidal weathering, one of the important rock weathering styles, has been attributed to chemical weathering by the water from joint surfaces, and mechanical aspects of the weathering have not been well addressed. We made an investigation on spheroidal weathering of Miocene granite porphyry with well‐developed columnar joints and found that this spheroidal weathering proceeds through chemical processes and accompanying mechanical processes. The investigation of the textures, physical properties, mineralogy, and chemistry of the porphyry revealed the presence of a brown band on the surface margins of corestones, representing the oxidation of pyrite and chlorite, and the precipitation of iron hydroxides, and the consequent generation of micro‐cracks within the band. During weathering, oxidation progresses inwards from joints that surround the rindlets, including both high‐angle columnar and low‐angle planar joints, and causes rounding of the unweathered interior portion of the rock. Microscopic observations of the brown band embedded with fluorescent resin show that pores are first filled with iron hydroxides, and that micro‐cracks then form parallel to the oxidation front in the outer portion of the brown band. Iron hydroxide precipitation increases the P‐wave velocity in the brown band, while micro‐crack formation decreases the tensile strength of the rock. Where the brown band has thickened to ~6 cm, the micro‐cracks are connected to one another to create continuous cracks, which separate the rindlets from the corestone. Micro‐crack formation parallel to the corestone surface may be attributed to compressive stresses generated by small amounts of volumetric expansion due to the precipitation of iron hydroxides in the brown band. Earth surface is under oxidizing environments so that precipitation of iron hydroxides commonly occurs; the spheroidal weathering in this paper is a typical example of the combination of chemical and mechanical processes under such environments. Copyright © 2016 John Wiley & Sons, Ltd.
Design of a Gigabit DSL modem using super orthogonal complete complementary codes
Authors: van Wyk Jacques H. , Linde Louis P.
Published: July 2016

This paper describes the preliminary design and simulation towards a gigabit digital subscriber line modem that provides multi‐user interference‐free communication in a far‐end crosstalk dominated environment by incorporating super orthogonal complete complementary spreading into the existing xDSL modem architecture. This is in contrast to existing vectoring and dynamic spectral management techniques that use joint processing and pre‐processing of each user's signal to mitigate far‐end crosstalk. A novel code allocation algorithm is introduced to provide all users with equal data rate ratios, even with bad line profiles and high‐required data rates. Preliminary simulation results show that 1 Gbps aggregate throughput can be obtained for the system over a single pair of 0.5 mm copper wire over a distance from 180 to 150 m, depending on whether ADSL2+ or VDSL2 Profile 30a service bands are avoided, if present. Copyright © 2016 John Wiley & Sons, Ltd.
Stabilized mixed three‐field formulation for a generalized incompressible Oldroyd‐B model
Authors: Kwack JaeHyuk , Masud Arif , Rajagopal K. R.
Published: July 2016

This paper presents a generalization of the incompressible Oldroyd‐B model based on a thermodynamic framework within which the fluid can be viewed to exist in multiple natural configurations. The response of the fluid is viewed as a combination of an elastic component and a dissipative component. The dissipative component leads to the evolution of the underlying natural configurations, while the response from the natural configuration to the current configuration is considered elastic and therefore non‐dissipative. For an incompressible fluid, it is necessary that both the elastic behavior as well as the dissipative behavior is isochoric. This is achieved by ensuring that the determinant of the stretch tensor associated with the elastic response meets the constraint that its determinant is unity.

A new stabilized mixed method is developed for the velocity, pressure and the kinematic tensor fields. Analytical models for fine scale fields are derived via the solution of the fine‐scale equations facilitated by the Variational Multiscale framework that are then variationally embedded in the coarse‐scale variational equations. The resulting method inherits the attributes of the classical SUPG and GLS methods, while a significant new contribution is that the form of the stabilization tensors is explicitly derived. A family of linear and quadratic tetrahedral and hexahedral elements is developed with equal‐order interpolations for the various fields. Numerical tests are presented that validate the incompressibility of the elastic stretch tensor, show optimal L2 convergence for the conformation tensor field, and present stable response for high Weissenberg number flows. Copyright © 2016 John Wiley & Sons, Ltd.
Images, imagination and the global environment: towards an interdisciplinary research agenda on global environmental images
Authors: Grevsmühl Sebastian Vincent
Published: July 2016

Global environmental images have become part of our everyday life experience. We encounter them in news reports, scientific articles and artistic interventions. Yet so far, only the most iconic of these images have received close critical attention from scholars coming mostly from two related fields, science studies and cultural geography. Some of those studies, as for instance research carried out on the famous Apollo photographs, have revealed that the icons of our environmental age do not provide simple readings, that they carry multiple, often contradicting messages, and that they can be vectors of highly ambiguous and even conflicting political beliefs. However, historically informed interdisciplinary research on visual cultures from an environmental perspective is still at its beginning. This essay thus calls for a systematic exploration of the crucial role the visual plays in the creation, circulation, interpretation and adaptation of global environmental knowledge. It is argued that this inquiry cannot be left solely to historians or geographers but calls for a truly interdisciplinary engagement. One central claim is that we need to better understand the constitutive role the visual and associated knowledge practices, conventions and infrastructures play in mediating global environmental phenomena. One possibility, it is argued, is to develop a broader historical framework for understanding how the visual actively shaped scientific and environmental discourse, and how it stimulated the rise of holistic and dynamic understandings of the environment from the nineteenth century onwards. A second important research area that is suggested concerns the crucial role global environmental images play at the interface of science discourse and environmental policy and governance. The essay concludes by suggesting three basic theses which seem particularly promising for future interdisciplinary inquiries into global environmental images.
Impacts of relative permeability formulation on forecasts of CO2 phase behavior, phase distribution, and trapping mechanisms in a geologic carbon storage reservoir*
Authors: Moodie Nathan , Pan Feng , Jia Wei , McPherson Brian
Published: July 2016

A critical aspect in the risk assessment of geologic carbon storage, a carbon‐emissions reduction method under extensive review and testing, is effective multiphase CO2 flow and transport simulation. Relative permeability is a flow parameter particularly critical for accurate forecasting of the multiphase behavior of CO2 in the subsurface. The relative permeability relationship assumed and especially the residual saturation of the gas phase greatly impacts predicted CO2 trapping mechanisms and long‐term plume migration behavior. A primary goal of this study was to evaluate the impact of the selection of relative permeability formulations on the efficacy of regional‐scale CO2 sequestration models. To accomplish this, we selected the San Rafael Swell area of East‐central Utah as a case study to evaluate the impact of relative permeability formulations on CO2 plume movement and behavior. A 2D vertical cross section model was built to simulate injection of CO2 into a brine aquifer for 30 years followed by 970 years of post‐injection monitoring. We evaluated five different relative permeability relationships to quantify their relative impacts on forecasted flow results of the model, with all other parameters maintained uniform and constant. Because of the interdependence between phase saturation and relative permeability in numerical simulations we expected to see some variation in phase behavior, phase distribution, and CO2 trapping mechanisms. An almost 60% difference in residually trapped gas was observed across the different relative permeability relationships. Large variations of up to 40% in the saturation of both dissolved phase and mobile supercritical phase CO2 were also observed. The pressure buildup and decay observed was not significantly affected by the relative permeability formulation until after injection pressures have dissipated. Results of this analysis suggest that CO2 plume movement and behavior are significantly dependent on the specific relative permeability formulation assigned, including the assumed residual saturation values of CO2 and brine. More specifically, different relative permeability relationships translate to significant differences in CO2 plume behavior and corresponding trapping mechanisms. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
Conditional rod photoreceptor ablation reveals Sall1 as a microglial marker and regulator of microglial morphology in the retina
Authors: Koso Hideto , Tsuhako Asano , Lai Chen‐Yi , Baba Yukihiro , Otsu Makoto , Ueno Kazuko , Nagasaki Masao , Suzuki Yutaka , Watanabe Sumiko
Published: July 2016

Neurodegeneration has been shown to induce microglial activation and the infiltration of monocyte‐derived macrophages into the CNS, resulting in the coexistence of these two populations within the same lesion, though their distinct features remain elusive. To investigate the impact of rod photoreceptor degeneration on microglial activation, we generated a toxin‐mediated genetic model of rod degeneration. Rod injury induced microglial proliferation and migration toward the photoreceptors. Bone marrow transplantation revealed the invasion of monocyte‐derived macrophages into the retina, with microglia and the infiltrating macrophages showing distinct distribution patterns in the retina. By comparing the gene expression profiles of the activated microglia and infiltrating macrophages, we identified microglia‐specific genes, including Ak1, Ctsf, Sall1, Phlda3, and Spns2. An analysis of Sall1gfp knock‐in mice showed GFP expression in the microglia of developing and mature healthy retinas. DTA injury induced the expansion of Sall1gfp+ microglia, whereas Ly6C+ monocyte‐derived macrophages were mostly Sall1gfp‐, supporting the idea that Sall1 is exclusively expressed in microglia within the retinal phagocyte pool. We evaluated the contribution of microglia to the phagocyte pool in rd1 mutant retinas and found that Sall1gfp+ microglia constituted the majority of phagocytes. A Sall1 deficiency did not affect microglial colonization of the retina and the cortex, but it did change their morphology from a ramified to a more amoeboid appearance. The morphological defects observed in Sall1‐deficient microglia were not rescued by the presence of wild‐type non‐microglial cells, suggesting that Sall1 functions cell‐autonomously in microglia. Taken together, our data indicate that Sall1 regulates microglial morphology during development. GLIA 2016;64:2005–2024