bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linking resource availability and heterogeneity to understorey species diversity through succession in boreal forest of Canada
Authors: Kumar Praveen , Chen Han Y. H. , Thomas Sean C. , Shahi Chander 
Published: August 2017

Abstract

Understorey vegetation comprises the majority of species diversity and contributes greatly to ecosystem functioning in boreal forests. Although patterns of understorey abundance, species diversity and composition associated with forest stand development are well researched, mechanisms driving these patterns remain largely speculative.

We sampled fire‐origin stands of varying stand ages and overstorey compositions on mesic sites of the boreal forest of Canada and used structural equation modelling (SEM) to link time since fire (stand age), light availability and heterogeneity, substrate heterogeneity and soil nitrogen to understorey vegetation cover and species diversity.

The most parsimonious model for total understorey cover showed a positive direct effect of stand age (r = .43) and an indirect effect via mean light level (0.18) and shrub cover (−0.11), with a positive total effect (0.50); the per cent broadleaf canopy had a direct negative effect (−0.22) and an indirect effect via shrub cover (−0.11). The model for total understorey species richness showed an indirect effect of stand age via mean light (0.24), light heterogeneity (0.10) and substrate heterogeneity (0.07), with a positive total effect (0.52); per cent broadleaf canopy had an indirect effect via light heterogeneity (0.09), and substrate heterogeneity (−0.10). Soil nitrogen did not significantly influence either understorey cover or species richness. The models for vascular plants followed similar trends to those for total understorey cover and species richness; however, there was an opposite indirect effect of light heterogeneity for both cover and species richness of non‐vascular plants. Shrub cover had positive direct and negative direct and indirect effects on both vascular and non‐vascular cover and species richness.

Synthesis. Our findings indicate that understorey cover and species diversity are driven by time since disturbance, light availability as influenced by overstorey and shrub layers, but with important additional effects mediated by light and substrate heterogeneity. Non‐vascular understorey vegetation is more strongly determined by time since disturbance than vascular vegetation, and negatively affected by broadleaf tree abundance. The overall results highlight the importance of colonization, light availability and heterogeneity, substrate specialization and growth dynamics in determining successional patterns of boreal forest understorey vegetation.
Strain‐specific consumption and transformation of alga‐derived dissolved organic matter by members of the Limnohabitans‐C and Polynucleobacter‐B clusters of Betaproteobacteria
Authors: Horňák Karel , Kasalický Vojtěch , Šimek Karel , Grossart Hans‐Peter 
Published: August 2017

SummaryWe investigated changes in quality and quantity of extracellular and biomass‐derived organic matter (OM) from three axenic algae (genera Rhodomonas, Chlamydomonas, Coelastrum) during growth of Limnohabitans parvus, Limnohabitans planktonicus and Polynucleobacter acidiphobus representing important clusters of freshwater planktonic Betaproteobacteria. Total extracellular and biomass‐derived OM concentrations from each alga were approximately 20 mg l−1 and 1 mg l−1 respectively, from which up to 9% could be identified as free carbohydrates, polyamines, or free and combined amino acids. Carbohydrates represented 54%–61% of identified compounds of the extracellular OM from each alga. In biomass‐derived OM of Rhodomonas and Chlamydomonas 71%–77% were amino acids and polyamines, while in that of Coelastrum 85% were carbohydrates. All bacteria grew on alga‐derived OM of Coelastrum, whereas only Limnohabitans strains grew on OM from Rhodomonas and Chlamydomonas. Bacteria consumed 24%–76% and 38%–82% of all identified extracellular and biomass‐derived OM compounds respectively, and their consumption was proportional to the concentration of each OM compound in the different treatments. The bacterial biomass yield was higher than the total identifiable OM consumption indicating that bacteria also utilized other unidentified alga‐derived OM compounds. Bacteria, however, also produced specific OM compounds suggesting enzymatic polymer degradation or de novo exudation.
Small‐p politics: how pleasurable, convivial and pragmatic political ideals influence engagement in eat‐local initiatives
Authors: Kennedy Emily Huddart , Johnston Josée , Parkins John R. 
Published: August 2017

AbstractNon‐confrontational engagement practices like ethical consumption are a popular form of everyday politics. Existing research into these practices offers positive evaluations (highlighting the value of everyday engagement in public life) and critical perspectives (questioning whether myriad small acts can address structural barriers to equity and sustainability). Meanwhile, less emphasis has been placed on understanding the underlying ideals and motivations for political action that seeks to avoid traditional politics. In order to advance such understanding, this case study uses participant observation and semi‐structured interviews with 57 individuals whose daily paid or unpaid leadership roles shape eat‐local initiatives. We find that in the local food realm, participants idealize pleasurable, convivial and pragmatic engagement and these ideals culminate in a particular form of everyday action we term ‘small‐p politics’. The paper offers a theoretically and empirically informed investigation of non‐traditional political engagement in eat‐local movements, concluding that it emerges from a site where: (a) cultural change is prioritized above contentious politics; (b) rejecting traditional political activity is linked with achieving tangible outcomes; and (c) consumers are deemed the ideal agents of change. Non‐traditional politics play a prominent role in the landscape of contemporary civic engagement. This research advances our existing knowledge of such practices by providing a thick description of the political ideals that endorse consumption‐based approaches to change in the realm of local food.
The Science of Impact and the Impact of Agricultural Science
Authors: Midmore Peter 
Published: August 2017

AbstractResearch impact and its measurement are of increasing importance. This is particularly significant for agricultural science, which is expected to produce solutions to future challenges that will arise from population growth, climate change and ecosystem degradation. Much econometric effort has been devoted to analysis of investment in agricultural research and its effects on farm productivity. This analysis, reviewed here, has produced a consensus suggesting that returns are high, although they are achieved only after long lags. However, policy‐makers perceive the occurrence of impacts as too few, and poorly targeted with respect to their needs. An attribution gap between the outcomes of agricultural research and how they reach farmers has motivated evaluation of the process of transmission and translation of agricultural research outputs into ultimate impacts. This gap can be narrowed by Participatory Impact Pathway Analysis, implemented mostly so far in low income countries. However, it is a costly and cognitively complex approach. Content analysis of the UK's 2014 REF Impact Case Studies uncovers the mind set of researchers and their managers regarding the description of impact and how it is supposed to occur. This reveals a nascent conservatism that focuses on research that can be shown to have impact, rather than research impact itself. From the overall discussion it can be concluded that the impact evaluation of agricultural science raises more profound issues than simply efficiency or transparency. Confirmation bias threatens impact evaluation, principally by distracting from other important stories about how and why the ultimate effects occur, but also by transforming the nature of the process itself. Methodological pluralism, with greater integration and triangulation between different evaluation approaches, is a promising means of resolving these problems.
Cell lines from diamondback moth exhibiting differential susceptibility to baculovirus infection and expressing midgut genes
Authors: Ma Xiao‐Li , He Wei‐Yi , Wang Ping , You Min‐Sheng 
Published: August 2017

AbstractSix new cell lines were established from embryonic tissues of the diamondback moth, Plutella xylostella (L.). The cell lines showed differential characteristics, including growth in attachment or in suspension, susceptibility to a baculovirus infection and expression of genes involved in the glucosinolate detoxification pathway in P. xylostella larvae. Five of the cell lines grew attached to the culture flask and one cell line grew unattached as a suspension cell line. The cell lines had population doubling times ranging from 18 to 23 h. Among five of the P. xylostella cell lines examined for infection of a nucleopolyhedrovirus from Autographa californica, AcMNPV, four cell lines were highly susceptible to AcMNPV infection, but one was only semi‐permissive to AcMNPV infection. The production of two recombinant proteins, a β‐galactosidase of bacterial origin and a secreted alkaline phosphatase of eukaryotic origin, in the P. xylostella cell lines was examined in comparison with that in the cell line Sf9 which is commonly used for recombinant protein production. In the P. xylostella cell lines, expression of three important midgut genes involved in the glucosinolate detoxification pathway, including the glucosinolate sulfatase genes GSS1 and GSS2 and the sulfatase modifying factor gene SUMF1, was detected. The P. xylostella cell lines developed in this study could be useful in in vitro research systems for studying insec–virus interactions and complex molecular mechanisms in glucosinolate detoxification and insect–plant interactions.
Late Miocene Pods and Leaves of Albizzia (Leguminosae: Mimosoideae) from Yunnan, SW China and Their Phytogeographic Implications
Authors: LI Binke , XIE Sanping , ZHANG Sihang , CHEN Tianyu , SHAO Yang 
Published: August 2017

AbstractAlbizzia is a leguminous genus belonging to the subfamily Mimosoideae with approximately 150 modern species, widely distributed in the tropical and subtropical regions of Asia, Africa, Australia and America. Among them, 17 species are mainly distributed in southern and southwestern China. Abundant fossils of the subfamily Mimosoideae, including leaves, pods, flowers and wood, have been reported from the Cretaceous and Paleogene strata of the Northern Hemisphere. However, Neogene records of Mimosoideae are relatively scarce. In this study, fossil pods and leaves belonging to the genus Albizzia from the Bangmai Formation of Yunnan, China were described. They were assigned to three species, including Albizzia scalpelliformis Guo, Li and Xie Emended, Albizzia cf. kalkora (Roxb.) Prain and Albizzia sp. The occurrence of Albizzia fossils from Lincang not only gives important information on the Neogene plant diversity from Yunnan—a worldwide famous biological hotspot—but also provides additional evidence for its phytogeographic history.
Oxidation and Mineralization of Mn2+ Ions Mediated by Pseudomonas putida: Insights from an Experimental Study
Authors: CHEN Xiaoye , LU Xiancai , LIU Huan , LI Juan , XIANG Wanli , ZHANG Rui , LU Jianjun 
Published: August 2017

AbstractThe formation of manganese oxides in nature is commonly mediated by microorganisms. In this study, the mineralization of biogenic manganese oxidation mediated by Pseudomanas putida has been experimentally investigated by employing various characterization techniques, including SEM, FESEM, TEM, XRD, and STXM‐NEXAFS. The results indicate that Mn2+ ions can be oxidized into Mn (IV) minerals (birnessite and pyrolusite) and Mn(III) minerals (hausmannite and feitknechtite), successively. The primary products (birnessite and pyrolusite) further transformed into hausmannite and feitknechtite under Mn2+ ion‐enriched conditions. However, birnessite and pyrolusite are the end‐products of the continuous microbial oxidation processes. These biogenic Mn oxides are poorly crystallized, which provides them with a high potential for usage in environmental restoration of contaminated soils and waters contaminated with heavy metals. The approaches employed in this study will also enrich genesis research of biological oxidation of Mn(II) species in nature.
Zircon U–Pb Geochronology and Geochemistry of the Early Cretaceous Volcanic Rocks from the Manitu Formation in the Hongol Area, Northeastern Inner Mongolia
Authors: ZHANG Xiangxin , SU Zhen , GAO Yongfeng 
Published: August 2017

AbstractWe undertook zircon U–Pb dating and geochemical analyses of volcanic rocks from the Manitu Formation in the Hongol area, northeastern Inner Mongolia, to determine their age, petrogenesis and sources, which are important for understanding the Late Mesozoic tectonic evolution of the Great Xing'an Range. The volcanic rocks of the Manitu Formation from the Hongol area consist primarily of trachyandesite, based on their chemical compositions. The zircons from two of these trachyandesites are euhedral–subhedral in shape, display clear oscillatory growth zoning and have high Th/U ratios (0.31–1.15), indicating a magmatic origin. The results of LA‐ICP‐MS zircon U–Pb dating indicate that the volcanic rocks from the Manitu Formation in the Hongol area formed during the early Early Cretaceous with ages of 138.9–140.5 Ma. The volcanic rocks are high in alkali (Na2O + K2O = 6.22–8.26 wt%), potassium (K2O = 2.49–4.58 wt%) and aluminium (Al2O3 = 14.27–15.88 wt%), whereas they are low in iron (total Fe2O3 = 3.76–6.53 wt%) and titanium (TiO2 = 1.02–1.61 wt%). These volcanic rocks are obviously enriched in large ion lithophile elements, such as Rb, Ba, Th and U, and light rare earth elements, and are depleted in high field strength elements, such as Nb, Ta and Ti with pronounced negative anomalies. Their Sr–Nd–Pb isotopic compositions show positive ∊Nd(t) (+0.16‰ to+1.64‰) and low TDM(t) (694–767 Ma). The geochemical characteristics of these volcanic rocks suggest that they belong to a shoshonitic series and were likely generated from the partial melting of an enriched lithospheric mantle that was metasomatised by fluids released from a subducted slab during the closure of the Mongol–Okhotsk Ocean. Elemental and isotopic features reveal that fractional crystallization with the removal of ferromagnesian minerals, plagioclase, ilmenite, magnetite and apatite played an important role during the evolution of the magma. These shoshonitic rocks were produced by the partial melting of the enriched lithospheric mantle in an extensional regime, which resulted from the gravitational collapse following the final closure of the Mongol–Okhotsk Ocean in the Middle–Late Jurassic.
Restoration of Eroded Thickness of the Neogene Strata in the Western Qaidam Basin and Its Significance for Oil and Gas Occurrence
Authors: SUN Ping , GUO Zeqing , HE Wenyuan , LIU Weihong 
Published: August 2017

AbstractDuring the Pleistocene, the western Qaidam Basin has largely experienced strong structural reconstruction and strong erosion. First, the eroded thickness of Neogene strata was restored approximately by the stratigraphic profile comparison method and plane trend surface restoring method; then, accurate calculation of erosion was recovered using vitrinite reflectance, and the erosion that was restored by the trend surface restoring method was corrected; finally, a distribution map of cumulative erosion was produced. This study marks an important achievement in that one of the most important parameters of basin tectonic evolution, sedimentary evolution, and oil and gas accumulation history has been obtained, and that a basic geological problem has been solved in the Qaidam Basin. The areas with high erosion and low erosion are shown in the map and a close relation between the distribution of oil and gas fields and erosion was recognized. Large and medium oil and gas fields are mainly distributed in areas with medium and low erosion. It is difficult to form large‐scale oil and gas accumulation in areas in which erosion is more than 2000 m. The mechanism of the relation between oil and gas distribution and erosion is explained. This study will be of use in predicting the distribution of oil and gas.
A Combination of N2 and CO2 Adsorption to Characterize Nanopore Structure of Organic‐Rich Lower Silurian Shale in the Upper Yangtze Platform, South China: Implications for Shale Gas Sorption Capacity
Authors: CHEN Lei , JIANG Zhenxue , LIU Keyu , GAO Fenglin , WANG Pengfei 
Published: August 2017

AbstractThe pores in shales are mainly of nanometer‐scale, and their pore size distribution is very important for the preservation and exploitation of shale gas. This study focused on the organic‐rich Lower Silurian black shale from four wells in the Upper Yangtze Platform, and their TOC, mineralogical composition and pore characterization were investigated. Low pressure N2 and CO2 adsorption were conducted at 77.35 K and 273.15 K, respectively, and the pore structures were characterized by modified Brunauer‐Emmett‐Teller (BET), Dubinin‐Radushkevich (DR), t‐plot, Barrett‐Joyner‐Halenda (BJH) and density functional theory (DFT) methods and then the relationship between pore structure and shale gas sorption capacity was discussed. The results indicate that (1) The Lower Silurian shale has high TOC content of 0.92%–4.96%, high quartz content of 30.6%–69.5%, and high clays content of 24.1%–51.2%. The total specific surface area varies from 7.56 m2/g to 25.86 m2/g. Both the total specific surface area and quartz content are positively associated with the TOC content. (2) Shale samples with higher TOC content have more micropores, which results in more complex nanopore structure. Micropore volumes/surface areas and non‐micropore surface areas all increase with the increasing TOC content. (3) A combination of N2 and CO2 adsorption provides the most suitable detection range (∼0.3–60 nm) and has high reliability and accuracy for nanopore structure characterization. (4) The TOC content is the key factor to control the gas sorption capacity of the Lower Silurian shale in the Upper Yangtze Platform.
Turbidite Events Recorded in Deep‐sea Core IR‐GC1 off Western Sumatra: Evidence from Grain‐size Distribution
Authors: QIU Zhongyan , HAN Xiqiu , WANG Yejian 
Published: August 2017

AbstractSediment core IR‐GC1, from the abyssal basin of the Indian Ocean off Sumatra, may provide important information on depositional events related to earthquakes and tsunamis. In this study, based on a combination of grain‐size analysis with lithological studies and oxygen isotope stratigraphy, seven deep‐sea turbidite layers were identified, corresponding to seven turbidity events that occurred at 128–130, 105–107, 98–100, 86–87, 50–53, 37–41 and 20–29 ka. The sediments of the turbidite deposits are characterized by coarse grain sizes, poor sorting, wide kurtosis, bimodal frequency distributions and clear depositional variations. Particle size grading is also an important signature of deep‐sea turbidite deposits and can be used as an indicator to identify turbidite layers. Possible triggering mechanisms for the turbidite events include tsunamis, earthquakes, volcanic eruptions and sea‐level changes.
The Financial Crisis of UNESCO after 2011: Political Reactions and Organizational Consequences
Authors: Hüfner Klaus 
Published: August 2017

AbstractThe present situation of UNESCO is unique in both, financial and legal terms. The United States with an assessment rate of 22 per cent to be contributed to the regular budget stopped paying its membership dues as of 2011 when the General Conference of UNESCO admitted Palestine as a Member State. But the United States decided to remain full member of the Organization. Israel followed the same way. The impact of an increasing ‘debt mountain’ over the years is obvious which led to a serious reduction in staff and activities. No one dares to question the issue of membership. Other member states started paying their annual dues either late or not at all. Ad hoc attempts of organizational change dominate the running of UNESCO without overcoming the existing fragmentation.
Overexpression of IFITM3 predicts poor prognosis in stage IIA esophageal squamous cell carcinoma after Ivor Lewis esophagectomy
Authors: Jia Yang , Xiao Zhaohua , Jiang Wenpeng , Chen Gang , Wang Zhou 
Published: August 2017

BackgroundRecent research has shown that IFITM3 plays an important role in the tumorigenesis of many malignancies. We investigated the clinicopathological variables and prognostic value of IFITM3 in stage IIA esophageal squamous cell carcinoma (ESCC) patients.MethodsImmunohistochemistry and Western blot analysis were used to examine IFITM3 expression in tumor specimens. The relationships between IFITM3 expression and clinicopathological variables, as well as the five‐year survival and recurrence status of patients, were analyzed.Results
IFITM3 was aberrantly expressed in tumor tissue. Statistical analysis showed a close correlation of IFITM3 expression with T tumor status (P = 0.004). Additionally, IFITM3 overexpression, advanced T status, poor degree of differentiation, and large tumor size were not only associated with poor survival but were high lymphatic metastatic recurrence predictors in ESCC patients (P < 0.05).ConclusionOur data indicated that IFITM3 overexpression may predict poor prognosis in stage IIA ESCC patients after Ivor Lewis esophagectomy.
Morphology of the thoracic limb of goat as evidenced by gross osteology and radiology
Authors: Makungu M. , Merere B. 
Published: August 2017

SummaryThe objective of this study was to provide the detailed normal gross osteology and radiographic anatomy of the thoracic limb in goats as a reference for clinical use and in biomedical research. Radiography of the thoracic limb was performed in five small East African goats. Radiographic findings were correlated with bone specimens from four adult small East African goats. The scapula was narrow. The major tubercle was large and extended proximally above the head of the humerus. The lateral supracondylar crest was less prominent. The lateral and medial epicondyles of the humerus were almost of the same size. The lateral surface of the lateral condyle of the humerus presented a prominent depression for the origin of extensors of the carpus and digits. The cranially located radial notch was deep seated and the radial tuberosity was represented by a rough area located nearer to the head of the radius. The fifth metacarpal bone was seen in all animals. The morphology of the thoracic limb of small East African goats indicated the presence of powerful extensor muscles and is restricted to forward and backward movements as an adaptation to terrestrial lifestyle.