581 research outputs found
Application of AIS Technology to Forest Mapping
Concerns about environmental effects of large scale deforestation have prompted efforts to map forests over large areas using various remote sensing data and image processing techniques. Basic research on the spectral characteristics of forest vegetation are required to form a basis for development of new techniques, and for image interpretation. Examination of LANDSAT data and image processing algorithms over a portion of boreal forest have demonstrated the complexity of relations between the various expressions of forest canopies, environmental variability, and the relative capacities of different image processing algorithms to achieve high classification accuracies under these conditions. Airborne Imaging Spectrometer (AIS) data may in part provide the means to interpret the responses of standard data and techniques to the vegetation based on its relatively high spectral resolution
Rhubarb extract partially improves mucosal integrity in chemotherapy-induced intestinal mucositis
AIM: To investigate the effects of orally gavaged aqueous rhubarb extract (RE) on 5-fluorouracil (5-FU)-induced intestinal mucositis in rats. METHODS: Female Dark Agouti rats (n = 8/group) were gavaged daily (1 mL) with water, high-dose RE (HDR; 200 mg/kg) or low-dose RE (LDR; 20mg/kg) for eight days. Intestinal mucositis was induced (day 5) with 5-FU (150 mg/kg) via intraperitoneal injection. Intestinal tissue samples were collected for myeloperoxidase (MPO) activity and histological examination. Xenopus oocytes expressing aquaporin 4 water channels were prepared to examine the effect of aqueous RE on cell volume, indicating a potential mechanism responsible for modulating net fluid absorption and secretion in the gastrointestinal tract. Statistical significance was assumed at P < 0.05 by one-way ANOVA. RESULTS: Bodyweight was significantly reduced in rats administered 5-FU compared to healthy controls (P < 0.01). Rats administered 5-FU significantly increased intestinal MPO levels (â„ 307%; P < 0.001), compared to healthy controls. However, LDR attenuated this effect in 5-FU treated rats, significantly decreasing ileal MPO activity (by 45%; P < 0.05), as compared to 5-FU controls. 5-FU significantly reduced intestinal mucosal thickness (by â„ 29% P < 0.001) as compared to healthy controls. LDR significantly increased ileal mucosal thickness in 5-FU treated rats (19%; P < 0.05) relative to 5-FU controls. In xenopus oocytes expressing AQP4 water channels, RE selectively blocked water influx into the cell, induced by a decrease in external osmotic pressure. As water efflux was unaltered by the presence of extracellular RE, the directional flow of water across the epithelial barrier, in the presence of extracellular RE, indicated that RE may alleviate water loss across the epithelial barrier and promote intestinal health in chemotherapy-induced intestinal mucositis. CONCLUSION: In summary, low dose RE improves selected parameters of mucosal integrity and reduces ileal inflammation, manifesting from 5-FU-induced intestinal mucositis.Juliana E Bajic, Georgina L Eden, Lorrinne S Lampton, Ker Y Cheah, Kerry A Lymn, Jinxin V Pei, Andrea J Yool, Gordon S Howart
Scaling up experimental ocean acidification and warming research: from individuals to the ecosystem
NERC UK Ocean Acidification Research Programme NE/HO1747X/1 The full text is under embargo until 17.08.1
Can we project changes in fish abundance and distribution in response to climate?
Large scale and long-term changes in fish abundance and distribution in response to climate change have been simulated using both statistical and process-based models. However, national and regional fisheries management requires also shorter term projections on smaller spatial scales, and these need to be validated against fisheries data. A 26-year time series of fish surveys with high spatial resolution in the North East Atlantic provides a unique opportunity to assess the ability of models to correctly simulate the changes in fish distribution and abundance that occurred in response to climate variability and change. We use a dynamic bioclimate envelope model forced by physical-biogeochemical output from eight ocean models to simulate changes in fish abundance and distribution at scales down to a spatial resolution of 0.5°. When comparing with these simulations with annual fish survey data, we found the largest differences at the 0.5° scale. Differences between fishery model runs driven by different biogeochemical models decrease dramatically when results are aggregated to larger scales (e.g. the whole North Sea), to total catches rather than individual species or when the ensemble mean instead of individual simulations are used. Recent improvements in the fidelity of biogeochemical models translate into lower error rates in the fisheries simulations. However, predictions based on different biogeochemical models are often more similar to each other than they are to the survey data, except for some pelagic species. We conclude that model results can be used to guide fisheries management at larger spatial scales, but more caution is needed at smaller scales
The grapevine uncharacterized intrinsic protein 1 (VvXIP1) is regulated by drought stress and transports glycerol, hydrogen peroxide, heavy metals but not water
A MIP (Major Intrinsic Protein) subfamily called Uncharacterized Intrinsic Proteins (XIP) was recently described in several fungi and eudicot plants. In this work, we cloned a XIP from grapevine, VvXIP1, and agrobacterium-mediated transformation studies in Nicotiana benthamiana revealed that the encoded aquaporin shows a preferential localization at the endoplasmic reticulum membrane. Stopped-flow spectrometry in vesicles from the aqy-null yeast strain YSH1172 overexpressing VvXIP1 showed that VvXIP1 is unable to transport water but is permeable to glycerol. Functional studies with the ROS sensitive probe CM-H(2)DCFDA in intact transformed yeasts showed that VvXIP1 is also able to permeate hydrogen peroxide (H2O2). Drop test growth assays showed that besides glycerol and H2O2, VvXIP1 also transports boric acid, copper, arsenic and nickel. Furthermore, we found that VvXIP1 transcripts were abundant in grapevine leaves from field grown plants and strongly repressed after the imposition of severe water-deficit conditions in potted vines. The observed downregulation of VvXIP1 expression in cultured grape cells in response to ABA and salt, together with the increased sensitivity to osmotic stress displayed by the aqy-null yeast overexpressing VvXIP1, corroborates the role of VvXIP1 in osmotic regulation besides its involvement in H2O2 transport and metal homeostasis.This work was supported by European Union Funds (FEDER/COMPETE Operational Competitiveness Programme) and Portuguese national Funds (FCT-Portuguese Foundation for Science and Technology): KBBE-2012-6-3117 "Inovinne", FCOMP-01-0124-FEDER-022692 and PTDC/AGR-ALI/100636/2008. HN (SFRH/BD/74257/2010) and APM (SFRH/BD/65046/2009) were supported by PhD grants from FCT. The Interuniversity Attraction Poles Programme-Belgian Science Policy (IAP7/29) and the Belgian French community ARC11/16-036 project.info:eu-repo/semantics/publishedVersio
Integrating ocean observations across bodyâsize classes to deliver benthic invertebrate abundance and distribution information
Invertebrate animals living at the seafloor make up a prominent component of life globally, spanning 10 orders of magnitude in body size over 71% of Earth's surface. However, integrating information across sizes and sampling methodologies has limited our understanding of the influence of natural variation, climate change and human activity. Here, we outline maturing practices that can underpin both the feasibility and impact of establishing Benthic Invertebrate Abundance and Distribution as a Global Ocean Observing SystemâEssential Ocean Variable, including: (1) quantifying individual body size, (2) identifying the well-quantified portions of sampled body-size spectra, (3) taking advantage of (semi-)automated information processing, (4) application of metadata standards such as Darwin Core, and (5) making data available through internationally recognized access points. These practices enable broader-scale analysis supporting research and sustainable development, such as assessments of indicator taxa, biodiversity, biomass, and the modeling of carbon stocks and flows that are contiguous over time and space
Is TEA an inhibitor for human Aquaporin-1?
Excessive water uptake through aquaporins can be life threatening, and disregulation of water permeability causes many diseases. Therefore, reversible aquaporin inhibitors are highly desired. In this paper, we identified the binding site for tetraethylammonium (TEA) of the membrane water channel aquaporin-1 by a combined molecular docking and molecular dynamics simulation approach. The binding site identified from docking studies was independently confirmed with an unbiased molecular dynamics simulation of an aquaporin tetramer embedded in a lipid membrane, surrounded by a 100-mM tetraethylammonium solution in water. A third independent assessment of the binding site was obtained by umbrella sampling simulations. These simulations, in addition, revealed a binding affinity of more than 17âkJ/mol, corresponding to an IC50 value of << 3âmM. Finally, we observed in our simulations a 50% reduction of the water flux in the presence of TEA, in agreement with water permeability measurements on aquaporin expressed in oocytes. These results confirm TEA as a putative lead for an aquaporin-1 inhibitor
Evaluation of ocean dimethylsulfide concentration and emission in CMIP6 models
Characteristics and trends of surface ocean dimethylsulfide (DMS) concentrations and fluxes into the atmosphere of four Earth system models (ESMs: CNRM-ESM2-1, MIROC-ES2L, NorESM2-LM, and UKESM1-0-LL) are analysed over the recent past (1980â2009) and into the future, using Coupled Model Intercomparison Project 6 (CMIP6) simulations. The DMS concentrations in historical simulations systematically underestimate the most widely used observed climatology but compare more favourably against two recent observation-based datasets. The models better reproduce observations in mid to high latitudes, as well as in polar and westerlies marine biomes. The resulting multi-model estimate of contemporary global ocean DMS emissions is 16â24âTgâSâyrâ1, which is narrower than the observational-derived range of 16 to 28âTgâSâyrâ1. The four models disagree on the sign of the trend of the global DMS flux from 1980 onwards, with two models showing an increase and two models a decrease. At the global scale, these trends are dominated by changes in surface DMS concentrations in all models, irrespective of the airâsea flux parameterisation used. In turn, three models consistently show that changes in DMS concentrations are correlated with changes in marine productivity; however, marine productivity is poorly constrained in the current generation of ESMs, thus limiting the predictive ability of this relationship. In contrast, a consensus is found among all models over polar latitudes where an increasing trend is predominantly driven by the retreating sea-ice extent. However, the magnitude of this trend between models differs by a factor of 3, from 2.9 to 9.2âGgâSâdecadeâ1 over the period 1980â2014, which is at the low end of a recent satellite-derived analysis. Similar increasing trends are found in climate projections over the 21st century
Alien Planktonic Species in the Marine Realm: What Do They Mean for Ecosystem Services Provision?
Human well-being is significantly affected by the contributions provided by ecosystems, or ecosystem services. In this well-illustrated atlas, world-class experts identify and discuss key driving forces, trade-offs, and synergies of ecosystem services. Through interdisciplinary case studies varying across ecosystems and scales, this atlas narrows the knowledge gap between ecosystem services management and related fields of study.
This atlas begins with conceptual background and proceeds to present drivers and their risks for ecosystems, their functions and services, and biodiversity. Trade-offs and synergies among ecosystem services and societal responses to the drivers and trade-offs are discussed. Sustainable land management and governance concepts are demonstrated throughout the atlas. Environmental scientists, practitioners and policy makers worldwide will appreciate the solutions and best practices identified throughout the chapters. Students of environmental sciences, socio-economics and landscape planning will find this atlas to be a valuable read, as well
Caregiver awareness of reproductive health issues for women with intellectual disabilities
<p>Abstract</p> <p>Background</p> <p>Limited attention has been paid to the issue of reproductive health as it affects women with intellectual disabilities, despite reproductive health being a vital issue in public health policy for women in the general population. This paper describes caregiver awareness of reproductive health issues relative to women with intellectual disabilities who are being cared for in welfare institutions in Taiwan.</p> <p>Methods</p> <p>The study employed a cross-sectional, questionnaire-based study which recruited 1,152 caregivers (response rate = 71.87%) from 32 registered disability welfare institutions in Taiwan. We classified their understanding/awareness of reproductive health issues into four domains: menstrual (1) and menopause (2) issues, sex education (3), and reproductive health services (4). Each domain had five associated yes/no questions and the total score for the four domains was out of a maximum of 20. Data were analyzed using SPSS 15.0 software.</p> <p>Results</p> <p>We found that most of the caregivers were familiar with matters concerning sex education, menopause, and reproductive health services, but they lacked adequate understanding of issues associated with menstruation in women with ID. Many aspects of reproductive health such as "menstrual pain", "age at menarche", "masturbation", "diet during perimenopause", and "publicly available reproductive health services" were issues in which caregivers lacked adequate knowledge and required further instruction. Logistic regression analysis revealed that female caregivers with a university degree, and those who had experience assisting with reproductive health care were more inclined to have higher reproductive health awareness scores than their counterparts.</p> <p>Conclusions</p> <p>This study highlights that service providers should offer appropriate reproductive health education to institutional caregivers, and that more attention be focused on the personal experiences and concerns of intellectually disabled women in future research.</p
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