bluuebunny/crossref_metadata_2025_split huggingface dataset:
Applying a dryland degradation framework for rangelands: the case of Mongolia
Authors: Jamsranjav C. , Reid R. S. , Fernández‐Giménez M. E. , Tsevlee A. , Yadamsuren B. , Heiner M. 
Published: March 2018

AbstractLivestock‐caused rangeland degradation remains a major policy concern globally and the subject of widespread scientific study. This concern persists in part because it is difficult to isolate the effects of livestock from climate and other factors that influence ecosystem conditions. Further, degradation studies seldom use multiple plant and soil indicators linked to a clear definition of and ecologically grounded framework for degradation assessment that distinguishes different levels of degradation. Here, we integrate two globally applicable rangeland degradation frameworks and apply them to a broad‐scale empirical data set for the country of Mongolia. We compare our assessment results with two other recent national rangeland degradation assessments in Mongolia to gauge consistency of findings across assessments and evaluate the utility of our framework. We measured livestock‐use impacts across Mongolia's major ecological zones: mountain and forest steppe, eastern steppe, steppe, and desert steppe. At 143 sites in 36 counties, we measured livestock‐use and degradation indicators at increasing distances from livestock corrals in winter‐grazed pastures. At each site, we measured multiple indicators linked to our degradation framework, including plant cover, standing biomass, palatability, species richness, forage quality, vegetation gaps, and soil surface characteristics. Livestock use had no effect on soils, plant species richness, or standing crop biomass in any ecological zone, but subtly affected plant cover and palatable plant abundance. Livestock effects were strongest in the steppe zone, moderate in the desert steppe, and limited in the mountain/forest and eastern steppes. Our results aligned closely with those of two other recent country‐wide assessments, suggesting that our framework may have widespread application. All three assessments found that very severe and irreversible degradation is rare in Mongolia (1–18% of land area), with most rangelands slightly (33–53%) or moderately (25–40%) degraded. We conclude that very severe livestock‐induced rangeland degradation is overstated in Mongolia. However, targeted rangeland restoration coupled with monitoring, adaptive management and stronger rangeland governance are needed to prevent further degradation where heavy grazing could cause irreversible change. Given the broad applicability of our degradation framework for Mongolia, we suggest it be tested for application in other temperate grasslands throughout Central Asia and North America.
Nonadaptive female pursuit of extrapair copulations can evolve through hitchhiking
Authors: Lyu Nan , Servedio Maria R. , Sun Yue‐Hua 
Published: March 2018

AbstractMounting evidence has indicated that engaging in extrapair copulations (EPCs) might be maladaptive or detrimental to females. It is unclear why such nonadaptive female behavior evolves. In this study, we test two hypotheses about the evolution of female EPC behavior using population genetic models. First, we find that both male preference for allocating extra effort to seek EPCs and female pursuit behavior without costs can be maintained and remain polymorphic in a population via frequency‐dependent selection. However, both behaviors cannot evolve when females with pursuit behavior suffer from a decline in male parental care. Second, we present another novel way in which female pursuit behavior can evolve; indirect selection can act on this behavior through a ratchet‐like mechanism involving oscillating linkage disequilibria between the target EPC pursuit locus and two other loci determining male mate choice and a female sexual signal. Although the overall positive force of such indirect selection is relatively weak, our results suggest that it may still play a role in promoting the evolution of female EPC behavior when this behavior is nonadaptive (i.e., it is neutral) or only somewhat maladaptive (e.g., males only occasionally lower parental care when their mates pursue EPCs).
Effect of growth temperature on photosynthetic capacity and respiration in three ecotypes of Eriophorum vaginatum
Authors: Schedlbauer Jessica L. , Fetcher Ned , Hood Katherine , Moody Michael L. , Tang Jianwu 
Published: March 2018

AbstractEcotypic differentiation in the tussock‐forming sedge Eriophorum vaginatum has led to the development of populations that are locally adapted to climate in Alaska's moist tussock tundra. As a foundation species, E. vaginatum plays a central role in providing topographic and microclimatic variation essential to these ecosystems, but a changing climate could diminish the importance of this species. As Arctic temperatures have increased, there is evidence of adaptational lag in E. vaginatum, as locally adapted ecotypes now exhibit reduced population growth rates. Whether there is a physiological underpinning to adaptational lag is unknown. Accordingly, this possibility was investigated in reciprocal transplant gardens. Tussocks of E. vaginatum from sites separated by ~1° latitude (Coldfoot: 67°15′N, Toolik Lake: 68°37′, Sagwon: 69°25′) were transplanted into the Toolik Lake and Sagwon sites and exposed to either an ambient or an experimental warming treatment. Five tussocks pertreatment combination were measured at each garden to determine photosynthetic capacity (i.e., Vcmax and Jmax) and dark respiration rate (Rd) at measurement temperatures of 15, 20, and 25°C. Photosynthetic enhancements or homeostasis were observed for all ecotypes at both gardens under increased growth temperature, indicating no negative effect of elevated temperature on photosynthetic capacity. Further, no evidence of thermal acclimation in Rd was observed for any ecotype, and there was little evidence of ecotypic variation in Rd. As such, no physiological contribution to adaptational lag was observed given the increase in growth temperature (up to ~2°C) provided by this study. Despite neutral to positive effects of increased growth temperature on photosynthesis in E. vaginatum, it appears to confer no lasting advantage to the species.
Floatability and a semiempirical model for resuspension thresholds of hydrochorous seeds
Authors: Zhu Xi , Zeng Yuhong , Huai Wenxin 
Published: March 2018

AbstractFloatability and incipient motion of seeds are the key indicators in primary and secondary dispersal during hydrochory, respectively. Floatability could prolong the time for seeds' survival in water and thereby extend the distance of primary dispersal. Seeds that were deposited but did not germinate may be resuspended and transported by currents farther until permanently stranded. This study aimed to describe and predict the dispersal patterns and movements of seeds with these 2 indicators under static and dynamic water conditions that correspond to the 2 aforementioned dispersal phases. The physical properties and hydrodynamic characteristics of seeds from 3 angiosperm species were used to study the floatability and resuspension thresholds of hydrochorous seeds. Floatability quantified by the number of seeds remaining buoyant varies among the 3 species, implicating their differing capabilities of primary dispersal. Resuspension thresholds of settled seeds were quantified by critical currents (shear velocities) that move seeds at rest on the bed sediment. On the basis of a model of nonuniform sand and collected experimental data, we proposed a model suitable for incipient motion of seeds from the bed. This model can be applied in the evaluation of secondary dispersal potential under different flow conditions. The preliminary research on the movements of seeds in water helps elucidate and determine species distribution and establishment. These factors are important in dispersal ecology.
Identifying foundation species in North American forests using long‐term data on ant assemblage structure
Authors: Record Sydne , McCabe Tempest , Baiser Benjamin , Ellison Aaron M. 
Published: March 2018

AbstractFoundation species are locally abundant and uniquely control associated biodiversity, whereas dominant species are locally abundant but are thought to be replaceable in ecological systems. It is important to distinguish foundation from dominant species to direct conservation efforts. Long‐term studies that remove abundant species while measuring community dynamics have the potential to (1) aid in the identification of foundation vs. dominant species and, (2) once a foundation species is identified, determine how long its effects persist within a community after its loss. Long‐term data on ant assemblages within two canopy‐manipulation experiments—the Harvard Forest Hemlock Removal Experiment (HF‐HeRE) and the Black Rock Future of Oak Forests Experiment (BRF‐FOFE)—provide insights into how ant assemblages change and reassemble following the loss of Tsuga canadensis or Quercus spp. Previous research documented foundation species effects on ants in the HF‐HeRE for up to four years after T. canadensis loss. Six additional years of data at HF‐HeRE presented for the first time here show that removal of T. canadensis resulted in taxonomic and some measures of functional shifts in ant assemblages that persisted for ten years, further supporting the hypothesis that T. canadensis is a foundation species at Harvard Forest. In contrast, ant assemblages at BRF‐FOFE varied little regardless of whether oaks or other tree species were removed from the canopy, suggesting that Quercus species do not act as foundation species at Black Rock Forest. Deer and moose exclosures within each experiment also allowed for comparisons between effects on ants of foundation or dominant tree species relative to effects of large herbivores. At HF‐HeRE, effects of T. canadensis were stronger than effects of large herbivores on taxonomic and functional diversity of ant assemblages. At BRF‐FOFE, in contrast, effects of Quercus species were weaker than effects of large herbivores on ant taxonomic diversity and some measures of ant functional diversity. These findings illustrate the importance of distinguishing between the roles of irreplaceable foundation species and replaceable dominant ones in forested ecosystems along with other drivers of biodiversity (e.g., herbivory).
Structural Optimization of Autonomous Energy Networks by Mathematical Programming Techniques
Authors: SAKAKIBARA KAZUTOSHI , MATSUMOTO TAKUYA , TANIGUCHI ITTETSU , TAMAKI HISASHI 
Published: March 2018

SUMMARYThe renewal of conventional energy systems is important countermeasures against global warming effects and natural hazards. A self‐sustainable decentralized energy system is one of the promising solutions for future sustainable and resilient societies. In this paper, a mathematical programming model is formulated and design and utilization of the overall energy network is optimized based on the model, where stationary batteries are equipped. Through some numerical simulation results, the effectiveness and the potential, for example, for clarifying the effect of the batteries, of the proposed model are investigated.
Development of Fast Derivation Method of Revenue Distribution for Power Trading Support
Authors: NAKAMURA RYOSUKE , YOKOTA TOSHIMI , TSURUGAI MITSUO , SAWA TOSHIYUKI 
Published: March 2018

SUMMARYWe are developing the power trading support system for judgment on making contract of negotiation transaction. About this system, fast derivation method of revenue distribution is developed. Calculation amount of deriving revenue is very large, because risk factors take a various value. Revenue is derived using “cost function” which represents the price against the amount of electricity generation. The total number is same as combination of risk factors. So, in developed method, risk factors are considered sequentially in calculation, and temporary cost function is assembled on each step. We evaluated the trade‐off of between effect of acceleration and error amount by example. We got the prospects that cumulative probability error is within 2% and calculation time is within 1 min.
Influence of Water and Temperature on Ionomer in Catalytic Layers and Membranes of Fuel Cells and Electrolyzers Evaluated by AFM
Authors: Morawietz T. , Handl M. , Oldani C. , Friedrich K. A. , Hiesgen R. 
Published: March 2018

AbstractThe major difference for the durability of the materials in PEM fuel cells and PEM electrolyzers is the exposure to humidified gases and to liquid water, respectively. Aquivion and Nafion ionomer was investigated at surfaces of membranes and cross‐sections of electrodes by material‐sensitive atomic force microscopy. The dimensional behavior of electrodes and membranes in a membrane‐electrode assembly cross section was studied as a function of combined humidity and temperature changes. The observed opposite effects of ionomer dimensional changes in membrane and catalytic layers are important for understanding mechanical stress factors and degradation. For the lamellar polymer phase at moderate humidity, a linear swelling behavior and the enclosure of multiples of 0.8 nm‐thick water layers was observed. Submersed in water, 3 nm‐thick enclosed water layers were found. At the water‐immersed Aquivion membrane derived from alcoholic dispersion larger 30–50 nm sized water‐rich areas were found. In contrast, for membranes derived from water‐based dispersion the water‐rich phase was smaller with 11 nm. The thickness of the ultrathin ionomer layers in the electrode was investigated as a function of humidity and temperature. A linear swelling was found for humidity changes whereas nonlinear behavior with 100% expansion and hysteresis was seen for temperature cycles.
Nonlinear Frequency Response Method for Evaluating Forced Periodic Operations of Chemical Reactors
Authors: Petkovska Menka , Nikolić Daliborka , Seidel‐Morgenstern Andreas 
Published: March 2018

AbstractNonlinear Frequency Response (NFR) method is a relatively new method which can be used for fast evaluation of possible process improvements through periodic operations. The method is analytical and approximate. Its main task is to give an answer whether periodic modulation of one or more process inputs can result in improved process performance. The method is explained in brief and an overview of the existing applications is given. The review covers simple reactions performed in isothermal and non‐isothermal stirred tank reactors exposed to different modulated inputs (inlet concentration, flow‐rate, inlet temperature, temperature of the heating/cooling medium). Processes with two simultaneously modulated inputs and different shapes of the periodic input are also considered. The results of the NFR method are compared with the results of numerical simulation and a critical evaluation of the method is given.
The euro area bias and the role of financial centres
Authors: Floreani Vincent Arthur , Habib Maurizio Michael 
Published: March 2018

AbstractThis paper investigates the euro area bias—a stronger preference for euro area securities in the cross‐border portfolio of euro area residents with respect to the prediction of an international finance gravity model. Compared with previous studies, we disentangle different partitions of the euro area and, crucially, isolate euro area financial centres, finding some novel results. First, the euro area bias is not always present and remarkably weak for securities issued by euro area high‐rating economies, those that would be expected to provide better insurance during crisis periods. Second, the extent of the euro area bias could be overstated, because euro area financial centres may conceal round‐tripping flows from euro area low‐rating economies. Finally, in the case of equity, the euro area bias did not decline during the crisis period but, in the case of debt issued by euro area low‐rating economies, unsurprisingly, weakened. The decline in exposure towards euro area debt securities was common among all cross‐border investors, not a specific retrenchment of euro area investors. Overall, our results call for a prudent treatment of cross‐border financial statistics in the presence of a financial centre bias.
Association between induced abortion history and later in vitro fertilization outcomes
Authors: Wang Yao , Sun Yun , Di Wen , Kuang Yan‐ping , Xu Bing 
Published: March 2018

AbstractObjectiveTo establish an effective and safe clinical fertility strategy by investigating the relationship between abortion history and pregnancy outcomes of in vitro fertilization (IVF) treatment.MethodsIn the present retrospective cohort study, data from IVF treatment cycles performed at a reproductive center in China between October 1, 2014, and October 31, 2015, were assessed. Outcomes were compared between women with a history of induced abortion and those without.ResultsThere were 1532 IVF treatment cycles included; 454 patients had a history of induced abortion and 1078 did not. The spontaneous abortion rate was significantly higher (30/170 [17.6%] vs 41/420 [9.8%]; P=0.002) and the endometrium was significantly thinner (8.8 ± 1.8 vs 9.7 ± 1.8 cm; P=0.001) among patients with a history of induced abortion compared with those without. In a subgroup analysis of patients with a history of induced abortion, women who had undergone surgical abortions had a lower live delivery rate compared with medical abortions (29/76 [38%] vs 101/378 [27%]; P=0.039). Further, women who had a history of more than two surgical abortions had lower live delivery and clinical pregnancy rates (both P<0.05).ConclusionA history of induced abortion was associated with worse IVF outcomes, especially a history of more than two surgical abortions.
Connecting Drip Irrigation Performance to Farmers’ Practices: The Case of Greenhouse Horticulture in the Algerian Sahara
Authors: Laib K. , Hartani T. , Bouarfa S. , Kuper M. , Mailhol J.C. 
Published: March 2018

AbstractDrip irrigation is widely used in a range of different farming systems. Farmers generally adapt drip irrigation systems to their specific conditions. Irrigation performance is usually related to the hydraulic parameters of drip irrigation, and is usually expressed as a single static value. We developed a comprehensive approach to account for irrigation performance as a dynamic process, which evolves continuously due to changes in the way farmers schedule irrigation and renew irrigation equipment. The performance of drip irrigation systems used for greenhouse horticulture was evaluated in south‐east Algeria in the 2012–2013 growing season. Two indicators were evaluated—distribution uniformity and water stress level. The approach was applied to 25 greenhouses owned by 13 farmers. Results revealed that the performance of drip irrigation systems is a dynamic process. We showed that farmers have integrated certain irrigation performance indicators such as distribution uniformity and water stress levels in their practices, as they have visible effects on crop production. Conversely, the relative irrigation supply does not directly interest the farmers, and was consequently not incorporated in their irrigation practices. We conclude that measuring drip irrigation performance must be accompanied by a broader understanding of the farming systems in which drip irrigation is used. Copyright © 2018 John Wiley & Sons, Ltd.
Inside Back Cover: Development of a 3‐dimensional tissue lung phantom of a preterm infant for optical measurements of oxygen—Laser‐detector position considerations (J. Biophotonics 3/2018)
Authors: Larsson Jim , Liao Peilang , Lundin Patrik , Krite Svanberg Emilie , Swartling Johannes , Lewander Xu Märta , Bood Joakim , Andersson‐Engels Stefan 
Published: March 2018

The picture depicts the different 3d‐printed organs, thorax, lungs, heart and bone. Assembled it is used as an optical phantom of a preterm infant for performing percutaneous optical measurements of the gas content in the lungs. In order to simulate the optical properties of the tissue, the heart and thorax can be filled with liquid phantoms, a mixture of Intralipid and Indian Ink.Further details can be found in the article by Jim Larsson et al. (e201700097).
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Nano‐layered TiO2 for effective bacterial disintegration of waste activated sludge and biogas production
Authors: Godvin Sharmila Vincent , Rajesh Banu Jeyakumar , Gunasekaran Muniappan , Angappane Subramanian , Yeom Ick Tae 
Published: March 2018

AbstractBACKGROUNDProper management of the huge amount of waste activated sludge generated during the conventional treatment of wastewater is nowadays a major environmental issue. Proper treatment of sludge needs huge investment and proper handling. To address this issue, the immobilized photocatalyst (TiO2) mediated exocellular fractionation of bacterial pretreatment for anaerobic digestion was utilized as a sludge treatment technique.RESULTTi was deposited on glass substrate by a DC spluttering technique, and a TiO2 layer was formed by annealing in oxygen atmosphere. This immobilized TiO2 efficiently extricated the extracellular components after 45 min by removing 99% of the total extractable extracellular polymeric substances. The exocellular fractionated bacterial pretreatment induced 20% of COD solubilization with methane generation of about 0.0217 g COD g‐1 COD d‐1, which was higher than the sludge without any treatment and sludge with bacterial pretreatment only.CONCLUSIONAn 8% increase in COD solubilization was achieved, which generated high quantities of methane. With the advantage of methane generation, the maximum profitable sludge reduction was obtained. Thin film deposition of TiO2 enables easy recovery of TiO2. The cost, energy, and solid balance analysis confirmed that this treatment method is field applicable. © 2018 Society of Chemical Industry