178 research outputs found

    A Primer on Gas Phase CO2 Production and Transport in Peatland Soils

    Get PDF
    CO2 sequestered by peatlands is accounted for and offset against national emissions. Observational and modelling studies are used to estimate emission factors that dictate the rate of CO2 emissions or removals from peatlands accounted for within the Landuse and landuse change including forestry (LULUCF) sector and often use simple Tier 1 emission factors found in the IPCC (1996) guidebook. However, the current estimates are predominately based off peatland surface fluxes measured using either chamber methods or eddy covariance techniques. These methods do not focus on sub-surface conditions while this information may prove useful in understanding efflux rates and conditions that influence them. To help assess the potential significance of subsurface dynamics in overall CO2 efflux rates from peatlands this study proposes to review the literature dealing with subsurface conditions. The review found that the production of CO2 in the sub-surface layers was often uncoupled from emissions and that on short time-scales the storage of CO2 in soil pores and dissolved in soil water may account for this. The rate of production was found to be influenced by decomposition rate, vegetation type, nutrient availability and peat depth. The review also found that the mechanism of transport of CO2 within the sub-surface was important in accounting for efflux rates. While diffusion is often assumed the most significant form of transport, the quantification and dynamics of other non-diffusive transport methods were found to also be important and further research is required to ascertain the drivers of both diffusive and non-diffusive transport

    Multinational perspectives on information technology from academia and industry

    Get PDF
    As the term \u27information technology\u27 has many meanings for various stakeholders and continues to evolve, this work presents a comprehensive approach for developing curriculum guidelines for rigorous, high quality, bachelor\u27s degree programs in information technology (IT) to prepare successful graduates for a future global technological society. The aim is to address three research questions in the context of IT concerning (1) the educational frameworks relevant for academics and students of IT, (2) the pathways into IT programs, and (3) graduates\u27 preparation for meeting future technologies. The analysis of current trends comes from survey data of IT faculty members and professional IT industry leaders. With these analyses, the IT Model Curricula of CC2005, IT2008, IT2017, extensive literature review, and the multinational insights of the authors into the status of IT, this paper presents a comprehensive overview and discussion of future directions of global IT education toward 2025

    The nutrition transition and its health implications in lower-income countries

    Get PDF
    OBJECTIVE: This article reviews information on the rapid changes in diet, activity and body composition that lower- and middle-income countries are undergoing and then examines some of the potential health implications of this transition. DESIGN AND SETTING: Data came from numerous countries and also from national food balance (FAOSTAT) and World Bank sources. Nationally representative and nationwide surveys are used. The nationally representative Russian Longitudinal Monitoring Surveys from 1992-96 and the nationwide China Health and Nutrition Survey from 1989-93 are examined in detail. RESULTS: Rapid changes in the structure of diet, in particular associated with urbanization, are documented. In addition, large changes in occupation types are documented. These are linked with rapid increases in adult obesity in Latin America and Asia. Some of the potential implications for adult health are noted. CONCLUSIONS: The rapid changes in diet, activity and obesity that are facing billions of residents of lower- and middle-income countries are cause for great concern. Linked with these changes will be a rapid increase in chronic diseases. Little to date has been done at the national level to address these problems

    Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

    Get PDF
    This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin

    Colorectal Adenomas in a Randomized Folate Trial: The Role of Baseline Dietary and Circulating Folate Levels

    Get PDF
    The Aspirin/Folate Polyp Prevention Study is a randomized, placebo-controlled trial of aspirin use and folic acid supplementation and incidence of colorectal adenomas in individuals with a history of these lesions. The trial showed that folic acid supplementation does not prevent the occurrence of new adenomas and may increase risk. We extend these results by investigating whether the effect of folic acid treatment differed by baseline dietary and circulating folate levels. Diet and supplement use were ascertained at baseline through a food-frequency questionnaire; a blood sample was used to determine plasma and red blood cell (RBC) folate levels. Individuals were followed for 3 years (1st follow up) and subsequently for an additional 3-5 years (2nd follow up). We used generalized linear regression to estimate risk ratios and 95% confidence limits as measures of association. There was little evidence that baseline dietary and total folate intake, and plasma and RBC folate modified the association between folic acid treatment and risk of any adenomas or advanced lesions. However, there was a protective association of the highest tertile of dietary and total intake as well as circulating folate with risk of any adenomas among those in the placebo group, but no association among individuals in the folic acid group. Our findings support the idea that while moderate doses of folate may be protective compared to deficiency, at some point of sufficiency supplementation provides no additional benefit

    Progenitor and stem cells for bone and cartilage regeneration

    Get PDF
    Research in regenerative medicine is developing at a significantly quick pace. Cell-based bone and cartilage replacement is an evolving therapy aiming at the treatment of patients who suffer from limb amputation, damaged tissues and various bone and cartilage-related disorders. Stem cells are undifferentiated cells with the capability to regenerate into one or more committed cell lineages. Stem cells isolated from multiple sources have been finding widespread use to advance the field of tissue repair. The present review gives a comprehensive overview of the developments in stem cells originating from different tissues and suggests future prospects for functional bone and cartilage tissue regeneration.The European Network of Excellence EXPERTISSUES (Project No. NMP3-CT-2004-500283), under which this work was carried out, is acknowledged

    Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber

    Get PDF
    Monoecious species provide a comprehensive system to study the developmental programs underlying the establishment of female and male organs in unisexual flowers. However, molecular resources for most monoecious non-model species are limited, hampering our ability to study the molecular mechanisms involved in flower development of these species. The objective of this study was to identify differentially expressed genes during the development of male and female flowers of the monoecious species Quercus suber, an economically important Mediterranean tree. Total RNA was extracted from different developmental stages of Q. suber flowers. Non-normalized cDNA libraries of male and female flowers were generated using 454 pyrosequencing technology producing a total of 962,172 high-quality reads with an average length of 264 nucleotides. The assembly of the reads resulted in 14,488 contigs for female libraries and 10,438 contigs for male libraries. Comparative analysis of the transcriptomes revealed genes differentially expressed in early and late stages of development of female and male flowers, some of which have been shown to be involved in pollen development, in ovule formation and in flower development of other species with a monoecious, dioecious, or hermaphroditic sexual system. Moreover, we found differentially expressed genes that have not yet been characterized and others that have not been previously shown to be implicated in flower development. This transcriptomic analysis constitutes a major step toward the characterization of the molecular mechanisms involved in flower development in a monoecious tree with a potential contribution toward the knowledge of conserved developmental mechanisms in other species.This work was funded by FEDER funds through the Operational Competitiveness Programme-COMPETE and by National Funds through FCT-Fundacao para a Ciencia e a Tecnologia under the project FCOMP-01-0124-FEDER-019461 (PTDC/AGR-GPL/118508/2010) and the sub-project SOBREIRO/0019/2009 within the National Consortium (COEC-Cork Oak ESTs Consortium). Romulo Sobral was supported by funding from FCT with a PhD grant (ref. SFRH/BD/84365/2012). Margarida Rocheta was supported by funding from FCT with a Post-Doc grant (ref. SFRH/BPD/64905/2009). Teresa Ribeiro was supported by funding from FCT with a Post-Doc grant (SFRH/BPD/64618/2009). We are grateful to Alexandre Magalhaes for the kind help given in bioinformatic analysis

    Envisioning surprises: How social sciences could help models represent ‘deep uncertainty’ in future energy and water demand

    Get PDF

    Plant chemicals and the sexual behavior of male tephritid fruit flies

    Get PDF
    Plant compounds affect insects in many different ways. In addition to being a food source, plants also contain secondary metabolites that may have positive and negative impacts on insects. The influence of these compounds on sexual behavior, in particular, has been the focus of many recent studies. Here, we review the existing literature on the effects of plant compounds on the sexual behavior of tephritid fruit fly males. We put special focus on polyphagous species whose males congregate in leks, where females exert strong mate selection. We first summarize the main findings related to plant compounds that increase male signaling behavior and attraction of females and consequently increase mating frequency, a phenomenon that has been recorded mainly for species of Anastrepha and Ceratitis. In other tephritid species, males are attracted to phenylpropanoids produced by plants (such as methyl eugenol or raspberry ketone) that, upon encounter, are consumed and sequestered by males. These compounds, or metabolic derivatives, which normally have negligible nutritional value, are included in the pheromone and also confer advantages in a sexual context: enhanced female attraction and improved male mating success. These phenomena have been reported for several Bactrocera species as well as for Zeugodacus cucurbitae. Because many tephritid species are serious pests, the effect of plant compounds on male behavior has been explored for potential incorporation into control strategies such as the sterile insect technique (SIT). We conclude noting several factors, such as age and nutrition during larval and adult stage, that modulate the effect of plant compounds on male mating behavior as well as some prominent gaps that preclude a thorough understanding of the plant-mediated enhancement of male sexual performance and hence limit our ability to effectively utilize phytochemicals in pest control strategies.Instituto de GenéticaFil: Segura, Diego Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Genética de Insectos de Importancia Económica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Belliard, Silvina A. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Genética de Insectos de Importancia Económica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vera, María Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Bachmann, Guillermo Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Genética de Insectos de Importancia Económica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ruiz, María Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Jofre-Barud, Flavia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernández, Patricia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Delta del Paraná; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lopez, M. Liza. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Shelly, Todd E. United States Department of Agriculture. Animal and Plant Health Inspection Service; Estados Unido

    Tissue engineering of functional articular cartilage: the current status

    Get PDF
    Osteoarthritis is a degenerative joint disease characterized by pain and disability. It involves all ages and 70% of people aged >65 have some degree of osteoarthritis. Natural cartilage repair is limited because chondrocyte density and metabolism are low and cartilage has no blood supply. The results of joint-preserving treatment protocols such as debridement, mosaicplasty, perichondrium transplantation and autologous chondrocyte implantation vary largely and the average long-term result is unsatisfactory. One reason for limited clinical success is that most treatments require new cartilage to be formed at the site of a defect. However, the mechanical conditions at such sites are unfavorable for repair of the original damaged cartilage. Therefore, it is unlikely that healthy cartilage would form at these locations. The most promising method to circumvent this problem is to engineer mechanically stable cartilage ex vivo and to implant that into the damaged tissue area. This review outlines the issues related to the composition and functionality of tissue-engineered cartilage. In particular, the focus will be on the parameters cell source, signaling molecules, scaffolds and mechanical stimulation. In addition, the current status of tissue engineering of cartilage will be discussed, with the focus on extracellular matrix content, structure and its functionality
    corecore