bluuebunny/crossref_metadata_2025_split huggingface dataset:
Why are monarch butterflies declining in the West? Understanding the importance of multiple correlated drivers
Authors: Crone Elizabeth E. , Pelton Emma M. , Brown Leone M. , Thomas Cameron C. , Schultz Cheryl B. 
Published: July 2019

AbstractUnderstanding the factors associated with declines of at‐risk species is an important first step in setting management and recovery targets. This step can be challenging when multiple aspects of climate and land use are changing simultaneously, and any or all could be contributing to population declines. We analyzed population trends of monarch butterflies in western North America in relation to likely environmental drivers. Unlike the larger eastern monarch population, past analyses of western monarchs have only evaluated the importance of climate (i.e., not land use) factors as drivers of abundance. We used partial least squares regression (PLSR) to evaluate the potential importance of changes in land use and climate variables. Trends in western monarch abundance were more strongly associated with land use variables than climate variables. Conclusions about importance of climate and land use variables were robust to changes in PLSR model structure. However, individual variables were too collinear to unambiguously separate their effects. We compared these conclusions to the more widely used technique of multiple regression, followed by multi‐model inference (MRMI). Naïve interpretation of MRMI results could be misleading, if collinearity were not taken into account. MRMI was also highly sensitive to variation in model construction. Our results suggest a two‐pronged approach to monarch conservation, specifically, starting efforts now to restore habitat, while also using experiments to more clearly delineate separate effects of climate and land use factors. They also demonstrate the utility of PLSR, a technique that is growing in use but is still relatively under‐appreciated in conservation biology.
Nitrogen controls the net primary production of an alpine Kobresia meadow in the northern Qinghai‐Tibet Plateau
Authors: Dai Licong , Ke Xun , Du Yangong , Zhang Fawei , Li Yikang , Li Qian , Lin Li , Peng Cuoji , Shu Kai , Cao Guangmin , Guo Xiaowei 
Published: July 2019

AbstractNet primary production (NPP) is a fundamental property of natural ecosystems. Understanding the temporal variations of NPP could provide new insights into the responses of communities to environmental factors. However, few studies based on long‐term field biomass measurements have directly addressed this subject in the unique environment of the Qinghai‐Tibet plateau (QTP). We examined the interannual variations of NPP during 2008–2015 by monitoring both aboveground net primary productivity (ANPP) and belowground net primary productivity (BNPP), and identified their relationships with environmental factors with the general linear model (GLM) and structural equation model (SEM). In addition, the interannual variation of root turnover and its controls were also investigated. The results show that the ANPP and BNPP increased by rates of 15.01 and 143.09 g/m2 per year during 2008–2015, respectively. BNPP was mainly affected by growing season air temperature (GST) and growing season precipitation (GSP) rather than mean annual air temperature (MAT) or mean annual precipitation (MAP), while ANPP was only controlled by GST. In addition, available nitrogen (AN) was significantly positively associated with BNPP and ANPP. Root turnover rate averaged 30%/year, increased with soil depth, and was largely controlled by GST. Our results suggest that alpine Kobresia meadow was an N‐limited ecosystem, and the NPP on the QTP might increase further in the future in the context of global warming and nitrogen deposition.
Bumble bee parasite prevalence but not genetic diversity impacted by the invasive plantImpatiens glandulifera
Authors: Vanderplanck Maryse , Roger Nathalie , Moerman Romain , Ghisbain Guillaume , Gérard Maxence , Popowski Dominik , Granica Sebastian , Fournier Denis , Meeus Ivan , Piot Niels , Smagghe Guy , Terrana Lucas , Michez Denis 
Published: July 2019

AbstractWhile many bee species are experiencing population declines, some host plant generalist bees remain common in Europe, partly because they seem able to shift to new resources. However, foraging on a new alternative plant, such as an invasive species, can modify diet quality and have a potentially detrimental effect on bee health. Herein, we investigated whether the spread of the invasive plantImpatiens glanduliferaaffectsBombus pascuorumpopulation regarding parasite prevalence, genetic structure, and nest density in Belgium. While no difference in bumble bee genetic structure was detected between invaded and uninvaded sites, we show thatI. glanduliferaoccurrence was significantly correlated with a decrease in the prevalence ofApicystis bombibut not the prevalence of three other parasite species (i.e.,Crithidia bombi,Nosema bombi,Nosema ceranae, andNosemasp.). Regarding our investigations, this effect was likely not due to variation in local bumble bee population fitness beforeI. glanduliferaflowering, nor to the relative abundance of other pollinators such asApis mellifera, but the unique chemical composition (i.e., polyphenol rich) of the pollen ofI. glanduliferaremained as an interesting hypothesis. WhereasB. pascuorumqueens probably colonize all the potential nesting sites in an area, invaded byI. glanduliferaor not, the abundance of polyphenol ampelopsin in pollen fromI. glanduliferapollen might reduce local parasite prevalence. Our field study confirms that bumble bee parasite prevalence is potentially related to the particular chemical composition of collected pollen. Plant traits such as secondary metabolite occurrence could play a key role in the health and conservation of bumble bees.
Fire, leaf harvest, and abiotic factors drive demography of an ecologically and culturally important understory plant
Authors: Hart‐Fredeluces G. , Ticktin T. 
Published: July 2019

AbstractUnderstanding how multiple simultaneous drivers interact to influence plant demography is critical for protecting plant diversity in the context of global change. Fire is a key disturbance in forested ecosystems, but the interactive effects of fire and other abiotic and management factors on understory plants are poorly understood. Beargrass (Xerophyllum tenax) is perennial herb that provides food, habitat, and nesting material for a wide range of animals. Beargrass populations are prescribe‐burned by Native American experts, and leaves are subsequently harvested at low‐intensity for use in weaving. Leaves for weaving are reportedly becoming harder to find due to lack of fire and competition with commercial harvesters. To elucidate the effects of fire and its interactions with leaf harvest and abiotic factors on beargrass populations, we collected demographic data on more than 1000 individuals over three years across fire severities in combination with individual‐level soil moisture and light measurements. We also conducted an experiment simulating low‐intensity leaf harvest. We built mixed‐effects models to test our predictions that fire would increase growth and reproduction, and that it would mediate the effects of soil moisture and leaf harvest on beargrass growth. Fire increased growth as well as sexual and vegetative reproduction, providing evidence that beargrass is fire‐adapted. Leaf harvest both reduced survival probability and increased the probability of vegetative reproduction. Individual growth increased with early growing season soil moisture in unburned and low‐severity fire areas but did not vary with soil moisture in high‐severity areas. In sum, fire is a key driver of beargrass demography and fire interacted with other factors to influence beargrass vital rates. Understanding the impacts of changes to management and abiotic factors on understory species such as beargrass, and the ecosystem services they provide, requires attention to interactions among multiple environmental factors.
Rain downpours affect survival and development of insect herbivores: the specter of climate change?
Authors: Chen Cong , Harvey Jeffrey A. , Biere Arjen , Gols Rieta 
Published: July 2019

AbstractChanges in the frequency, duration, and intensity of rainfall events are among the abiotic effects predicted under anthropogenic global warming. Heavy downpours may profoundly affect the development and survival of small organisms such as insects. Here, we examined direct (physically on the insects) and indirect (plant‐mediated) effects of simulated downpours on the performance of caterpillars of two lepidopteran herbivores (Plutella xylostella and Pieris brassicae) feeding on black mustard (Brassica nigra) plants. Host plants were exposed to different rainfall regimes both before and while caterpillars were feeding on the plants in an attempt to separate direct and indirect (plant‐mediated) effects of rainfall on insect survival and development. In two independent experiments, downpours were simulated as a single long (20 min) or as three short (5 min) daily events. Downpours had a strong negative direct effect on the survival of P. xylostella, but not on that of P. brassicae. Direct effects of downpours consistently increased development time of both herbivore species, whereas effects on body mass depended on herbivore species and downpour frequency. Caterpillar disturbance by rain and recorded microclimatic cooling by 5°C may explain extended immature development. Indirect, plant‐mediated effects of downpours on the herbivores were generally small, despite the fact that sugar concentrations were reduced and herbivore induction of secondary metabolites (glucosinolates) was enhanced in plants exposed to rain. Changes in the frequency of precipitation events due to climate change may impact the survival and development of insect herbivores differentially. Broader effects of downpours on insects and other arthropods up the food chain could seriously impair and disrupt trophic interactions, ultimately destabilizing communities.
Volatility forecasting with bivariate multifractal models
Authors: Liu Ruipeng , Demirer Riza , Gupta Rangan , Wohar Mark 
Published: July 2019

AbstractThis paper examines volatility linkages and forecasting for stock and foreign exchange markets from a novel perspective by utilizing a bivariate Markov‐switching multifractal model that accounts for possible interactions between stock and foreign exchange markets. Examining daily data from major advanced and emerging nations, we show that generalized autoregressive conditional heteroskedasticity models generally offer superior volatility forecasts for short horizons, particularly for foreign exchange returns in advanced markets. Multifractal models, on the other hand, offer significant improvements for longer horizons, consistently across most markets. Finally, the bivariate multifractal model provides superior forecasts compared to the univariate alternative in most advanced markets and more consistently for currency returns, while its benefits are limited in the case of emerging markets.
Experimental and analytical investigation on an automobile radiator with CuO/EG‐water based nanofluid as coolant
Authors: Maisuria Mahendra B. , Sonar Devendraprasad M. , Rathod Manish K. , Bhatt Manhar K. 
Published: July 2019

AbstractIn the present study, experimental and analytical thermal performance of automobile radiator using nanofluids is investigated and compared with performance obtained with conventional coolants. Effect of operating parameters and nanoparticle concentration on heat transfer rate are studied for water as well as CuO/EG‐water based nanofluid analytically. The results are presented in the form of graphs showing variations of net heat transfer rate for various coolant flow rate, air velocity, and source temperature for various CuO/EG‐water based nanofluids. Experimental results indicate that with the increase in coolant flow rate and air velocity, heat transfer rate increases, reaches maximum and then decreases. Experimental investigation of a radiator is carried out using CuO/EG‐water based nanofluids. Results obtained by experimental work and analytical MATLAB code are almost the same. Maximum absolute error in water and air side is within 12% for all flow condition and coolant fluids. Nusselt number of nanofluid is calculated using equation number 33[9]. The results obtained from experimental work using 0.2% volume CuO/EG‐water based nanofluids are compared with the results obtained from MATLAB code. The results show that the maximum error in the outlet temperature of the coolant and air is 12% in each case. Thus MATLAB code can be used for different concentration of nanofluids to study the effect of operating parameters on heat transfer rate. Thus MATLAB code developed is valid for given heat exchanger applications. From the results obtained by already validated MATLAB code, it is concluded that increase in coolant flow rate, air velocity, and source temperature increases the heat transfer rate. Addition of nanoparticles in the base fluid increases the heat transfer rate for all kind of base fluids. Among all the nanofluid analyzed in this study, water‐based nanofluid gives highest value of heat transfer rate and is recommended for the heat exchanger applications under normal operating conditions. Maximum enhancement is observed for ethylene glycol‐water (4:6) mixture for 1% volume concentration of CuO is almost equal to 20%. As heat transfer rate increases with the use of nanofluids, the heat transfer area of the radiator can be minimized.
Modeling the effective thermal conductivity of nanofluids using full factorial design analysis
Authors: Grine Wassila , Benhamza Mohamed E. H. 
Published: July 2019

AbstractIn this paper, a full factorial design analysis is proposed for predicting nanofluid thermal conductivity ratio (TCR) as well as determining the effects of critical factors and their interactions. A statistical design of experiment approach with three variables (volume fraction, temperature, and nanoparticle diameter) at two levels is carried out. Three types of oxide‐water nanofluids (Al2O3‐water, CuO‐water, and TiO2‐water) are used to evaluate the effectiveness of the proposed mathematical model. The significance and adequacy of the regression model were evaluated by the analysis of variance. The predicted model has a root mean square error equals to 0.0074, R2 = 0.99, and P < .0013, thus showing good results compared to a set of experimental data as well as other mathematical model results. The results illustrate that the TCR of metallic oxide nanoﬂuids increases with temperature and nanoparticles volume fraction but decreases when nanoparticle size intensiﬁes. Furthermore, it is found that the nanoparticles volume fraction has a great impact on the nanoﬂuids thermophysical properties. Finally, the obtained results confirm that the proposed model is considerably accurate and capable of predicting nanoﬂuids thermal conductivity and that it can be used with ease as an alternative to many other models.
Analyzing credit risk transmission to the nonfinancial sector in Europe: A network approach
Authors: Gross Christian , Siklos Pierre L. 
Published: July 2019

SummaryWe use a factor model and elastic net shrinkage to model a high‐dimensional network of European credit default swap (CDS) spreads. Our empirical approach allows us to assess thejointtransmission of bank and sovereign risk to the nonfinancial corporate sector. Our findings identify a sectoral clustering in the CDS network, where financial institutions are in the center and nonfinancial entities as well as sovereigns are grouped around the financial center. The network has a geographical component reflected in different patterns of real‐sector risk transmission across countries. Our framework also provides dynamic estimates of risk transmission, a useful tool for systemic risk monitoring.
MicroRNA‐140 inhibit prostate cancer cell invasion and migration by targeting YES proto‐oncogene 1
Authors: Zhao Shijia , Jie Chuanling , Xu Pengchao , Diao Yan 
Published: July 2019

AbstractProstate cancer (PCa), which is an aggressive malignancy of the male genitourinary system. In the present study, the effects of microRNA‐140 (miR‐140) on PCa were determined. We transfected miR‐140 mimics or negative control into PCa cells, and we used MTT, wound healing, and Transwell assays for determining the capacities of miR‐140 in cell proliferation, migration, and invasion, respectively. We also confirmed the relationship between miR‐140 and YES proto‐oncogene 1 (YES1) using Luciferase reporter assay. The results showed that miR‐140 was downregulated in PCa cells and tissues, and overexpression of miR‐140 could significantly suppress their capacities of proliferation, migration, and invasion. Moreover, YES1 was shown to be a direct target of miR‐140. Moreover, miR‐140 expression is negatively correlated with YES1 levels. miR‐140 exhibits significant tumor‐suppressive effects in PCa by inhibiting YES1. The study indicated that miR‐140 and YES1 could be the potential targets for PCa therapy.
Glutathione peroxidase 3 (GPX3) suppresses the growth of melanoma cells through reactive oxygen species (ROS)‐dependent stabilization of hypoxia‐inducible factor 1‐α and 2‐α
Authors: Yi Zihan , Jiang Lu , Zhao Lei , Zhou Meiling , Ni Yueli , Yang Yuye , Yang Huixin , Yang Lijuan , Zhang Qiao , Kuang Yingmin , Deng Mingjia , Zhu Yuechun 
Published: July 2019

AbstractIn this study, we aimed to explore the mechanism of glutathione peroxidase 3 (GPX3) in the growth of malignant melanoma (MM) cells by hypoxia‐inducible factor‐1α (HIF1‐α) and HIF2‐α regulating the metabolism through reactive oxygen species (ROS). The messenger RNA and protein expression of GPX3, HIF1‐α, HIF2‐α in tissues, and cell lines were measured by reverse transcription‐quantitative PCR and Western blot analysis. A375 cells were transfected with GPX3 overexpression plasmid, small interfering RNA (siRNA) targeting GPX3, or siRNA targeting HIF1‐α/HIF2‐α to upregulate or downregulate the expression of GPX3 or HIF1‐α/HIF2‐α. The effects of H2O2 and N‐acetylcysteine (NAC) on the levels of HIF1‐α and HIF2‐α after overexpression of GPX3 were studied. The cell viability was detected by Cell Counting Kit‐8. The levels of ROS, glucose uptake and lactic acid production, oxidative phosphorylation, and glycolysis of cells were measured for assessment of cellular metabolism. The expression of GPX3 decreased, while ROS, HIF1‐α, and HIF2‐α increased in MM tissues and cells. Overexpression of GPX3 inhibited the viability of MM cells and the growth of melanoma xenografts. The overexpression of GPX3 reduced the glucose uptake, extracellular lactic acid content, and extracellular acidification rate and increased the oxygen consumption rate level. Overexpression of GPX3 could reduce the levels of HIF1‐α and HIF2‐α, which could regulate metabolic levels. GPX3 reduced ROS level in MM to inhibit HIF1‐α and HIF2‐α. The addition of H2O2 increased while NAC reduced the protein levels of HIF1‐α and HIF2‐α in the cells overexpressing GPX3. Our study demonstrates that GPX3 inhibits the growth of MM cells through its inhibitory effect on cell metabolic disorder by inhibiting HIF1‐α via regulating ROS.
Retracted: Long noncoding RNA Alu‐mediated p21 transcriptional regulator promotes proliferation, migration, and pipe‐formation of human microvascular endothelial cells by sponging miR‐126
Authors: Song Aiping , Feng Rong , Gao Jianying , Yang Chunqing 
Published: July 2019

AbstractPeripheral artery disease (PAD) is a serious hazard to the elderly in the lower extremity atherosclerotic plaque, accompanied by a large number of angiogenesis. Long noncoding RNA Alu‐mediated p21 transcriptional regulator (APTR) exerts important functions in promoting cell growth. Therefore, we planned to research the mechanism of APTR in angiogenesis in PAD. CCK‐8 assay, flow cytometry analysis, and migration assay were to detect cell viability, apoptosis, and migration respectively. The interaction between APTR and miR‐12 was tested through luciferase activity test. In vitro angiogenesis assay was used to test the number of tubular cells. qRT‐PCR and Western blot were to test expression of APTR, miR‐126, and angiogenesis relative factors. There was spontaneously pipe‐formation in HEMC‐1 cells under matrigel condition. Knockdown of APTR inhibited cell viability and migration and reduced the number of tubular cells. Further, APTR sponged miR‐126 and downregulating miR‐126 to promote angiogenesis. Overexpression of APTR promoted cell activity and migration and increased the number of tubular cells via negatively regulating miR‐126. APTR could elevate activating phosphatidylinositol 3 kinase/protein kinase B and mitogen extracellular kinase/extracellular signal‐regulated kinase signal pathways via negatively regulating miR‐126 to promote cell proliferation, migration, and pipe‐formation. We researched the mechanism of angiogenesis that APTR elevated proliferation, migration, and pipe‐formation via negatively regulating miR‐126.
An evaluation of different Cripto‐1 antibodies and their variable results
Authors: Gudbergsson Johann Mar , Duroux Meg 
Published: July 2019

AbstractCripto‐1 is a protein expressed during embryonal development and has been linked to several malignant processes in cancer. Since the discovery of cripto‐1 in the late 1980s, it has become a subject of biomarker investigation in several types of cancer which in many cases relies on immunolocalization of cripto‐1 using antibodies. Investigating cripto‐1 expression and localization in primary glioblastoma cells, we discovered nonspecific binding of cripto‐1 antibody to the extracellular matrix Geltrex. A panel of four cripto‐1 antibodies was investigated with respect to their binding to the Geltrex matrix and to the cripto‐1 positive control cells NTERA2. The cripto‐1 expression was varied for the different antibodies with respect to cellular localization and fixation methods. To further elaborate on these findings, we present a systematic review of cripto‐1 antibodies found in the literature and highlight some possible cross reactants with data on sequence alignments and structural comparison of EGF domains.