151 research outputs found
ECOSSE: Estimating Carbon in Organic Soils - Sequestration and Emissions: Final Report
Background
Climate change, caused by greenhouse gas ( GHG) emissions, is one of the most serious threats facing our planet, and is of concern at both UK and devolved administration levels. Accurate predictions for the effects of changes in climate and land use on GHG emissions are vital for informing land use policy. Models which are currently used to predict differences in soil carbon (C) and nitrogen (N) caused by these changes, have been derived from those based on mineral soils or deep peat. None of these models is entirely satisfactory for describing what happens to organic soils following land-use change. Reports of Scottish GHG emissions have revealed that approximately 15% of Scotland's total emissions come from land use changes on Scotland's high carbon soils; the figure is much lower for Wales. It is therefore important to reduce the major uncertainty in assessing the carbon store and flux from land use change on organic soils, especially those which are too shallow to be deep peats but still contain a large reserve of C.
In order to predict the response of organic soils to external change we need to develop a model that reflects more accurately the conditions of these soils. The development of a model for organic soils will help to provide more accurate values of net change to soil C and N in response to changes in land use and climate and may be used to inform reporting to UKGHG inventories.
Whilst a few models have been developed to describe deep peat formation and turnover, none have so far been developed suitable for examining the impacts of land-use and climate change on the types of organic soils often subject to land-use change in Scotland and Wales. Organic soils subject to land-use change are often (but not exclusively) characterised by a shallower organic horizon than deep peats (e.g. organo-mineral soils such as peaty podzols and peaty gleys). The main aim of the model developed in this project was to simulate the impacts of land-use and climate change in these types of soils. The model is, a) be driven by commonly available meteorological data and soil descriptions, b) able to simulate and predict C and N turnover in organic soils, c) able to predict the impacts of land-use change and climate change on C and N stores in organic soils in Scotland and Wales.
In addition to developing the model, we have undertaken a number of other modelling exercises, literature searches, desk studies, data base exercises, and experimentation to answer a range of other questions associated with the responses of organic soils in Scotland and Wales to climate and land-use change.
Aims of the ECOSSE project
The aims of the study were:
To develop a new model of C and N dynamics that reflects conditions in organic soils in Scotland and Wales and predicts their likely responses to external factors
To identify the extent of soils that can be considered organic in Scotland and Wales and provide an estimate of the carbon contained within them
To predict the contribution of CO 2, nitrous oxide and methane emissions from organic soils in Scotland and Wales, and provide advice on how changes in land use and climate will affect the C and N balance
In order to fulfil these aims, the project was broken down into modules based on these objectives and the report uses that structure. The first aim is covered by module 2, the second aim by module 1, and the third aim by modules 3 to 8. Many of the modules are inter-linked.
Objectives of the ECOSSE project
The main objectives of the project were to:
Describe the distribution of organic soils in Scotland and Wales and provide an estimate of the C contained in them
Develop a model to simulate C and N cycling in organic soils and provide predictions as to how they will respond to land-use, management and climate change using elements of existing peat, mineral and forest soil models
Provide predictive statements on the effects of land-use and climate change on organic soils and the relationships to GHG emissions, including CO 2, nitrous oxide and methane.
Provide predictions on the effects of land use change and climate change on the release of Dissolved Organic Matter from organic soils
Provide estimates of C loss from scenarios of accelerated erosion of organic soils
Suggest best options for mitigating C and N loss from organic soils
Provide guidelines on the likely effects of changing land-use from grazing or semi-natural vegetation to forestry on C and N in organic soils
Use the land-use change data derived from the Countryside Surveys of Scotland and Wales to provide predictive estimates for changes to C and N balance in organic soils over time
Natural selection for efficiency in the use of nitrogen in common bean identified by analysis of microsatellites and grain yield
Abstract This study was carried out in order to verify whether natural
selection acts on segregating common bean populations grown in the
presence and absence of N, and to verify that natural selection affects
the frequency of microsatellite alleles specifically, and in order to
identify those that can assist in selection. Four populations from the
crosses Ouro Negro x CI-107 and VC-5 x IAPAR-81 were carried forward in
bulk to F8 at both levels of N. Ouro Negro and VC-5 are considered
stress tolerant to nitrogen and IAPAR-81 and CI-107 responsive. One
hundred progenies were obtained from each cross and grown in the
presence and absence of N. DNA was extracted from 400 progenies, of
which 194 were evaluated in the rainy season and 79 in the winter crop
for grain yield. These progenies were evaluated in two separate
experiments with and without N, in a 14 x 14 lattice design during
rainy season and 9 x 9 in the winter season. We selected 35 pairs of
polymorphic primers from the parents, with 20 being common from the two
crosses. Using DNA of the 400 progenies, it was found that natural
selection acted in 33 loci, in at least one environment and cross, and
that alleles of the four parents were favoured by natural selection.
QTLs were identified for the response rate of N and for grain yield and
the linked markers are potential for assisted selection, especially the
two most stable; BMD-20, in response to the use of N and PVBR-93 for
grain yield
Sources, behaviour and mitigation strategies influencing indoor air quality
The particulate impact on air quality of typical domestic behaviours (e.g. cleaning and cooking) and their potential mitigation strategies (e.g. increasing ventilation) was investigated in the DOMESTIC unit at University of Chester. A 'typical day' based on the UK Time Use Survey of 2014-15 and tested under 2 separate ventilation conditions for 2 days each. This clearly indicated the impacts of different activities and the reduction of particulate levels with higher ventilation
Simulation of flash-butt welding process of a railway steel. Part 1 : residual stress analysis via FEM.
Trilhos longos, soldados pelo processo Flash Butt Welding (FBW), s?o a realidade das ferrovias brasileiras de m?dia e alta carga por eixo. Embora apresentem caracter?sticas desej?veis do ponto de vista do comportamento din?mico da via, as soldas s?o regi?es de descontinuidade estrutural e mec?nica onde se originam tens?es residuais, e que est?o associadas a falhas prematuras por fadiga. Simula??es num?ricas termomec?nicas, fisicamente n?o-lineares, no dom?nio do tempo, pelo M?todo dos Elementos Finitos (MEF), foram empregadas para avaliar o desenvolvimento de tens?es residuais originadas durante o processo de soldagem. Uma nova abordagem para a inclus?o do aporte de calor envolvido no processo ? proposta. Os resultados num?ricos s?o comparados a medidas experimentais de tens?es residuais superficiais e aspectos macrogr?ficos das juntas, incluindo largura da Zona Termicamente Afetada (ZTA) e dados de taxas de resfriamento. Os resultados mostram boa correla??o entre as an?lises num?ricas e medidas experimentais de tens?es residuais. Aspectos fundamentais relacionados ao desenvolvimento de tens?es residuais s?o esclarecidos a partir da correla??o entre an?lises num?rica e experimental. Ademais, verifica-se que os modelos computacionais podem ser utilizados na previs?o de pontos cr?ticos para nuclea??o de trincas por fadiga e/ou avaliar efeitos de vari?veis de processo sobre o campo de tens?es residuais.Long rails, welded by the Flash-Butt Welding (FBW) process, are the reality of the Brazilian railroads for medium and high axle loads. Although they present desirable characteristics concerning the dynamic behavior of the track, welded joints are regions of structural and mechanical discontinuity where high residual stresses originate, and, consequently, premature fatigue failures may take place. This paper employs the Finite Element Method (FEM) to carry out transient, physically non-linear thermo-mechanical analyses to evaluate residual stresses evolved in the welding process. A new approach is proposed to take into account the heat input involved in the process. The numerical results are compared to experimentally measured surface residual stresses, and to the macrographic joint aspects, including the HAZ width and cooling rate data. The results show a good correlation between the numerical and experimental measurements of residual stresses. Fundamental aspects related to the development of residual stresses are clarified, correlating numerical and experimental analyses. In addition, it is verified that the computational models can be used to predict critical crack nucleation points by fatigue, and/or to evaluate effects of process parameters on the residual stress field
Is the Rehbein procedure obsolete in the treatment of Hirschsprung’s disease?
Contains fulltext :
87916.pdf (publisher's version ) (Closed access)PURPOSE: After 25 years of practice and positive results of the Rehbein-procedure (RB) for children with Hirschsprung Disease (HD), we changed to the less invasive transanal endorectal pull through (TERPT). The aim of this study was to compare short- and mid-term complications of these two procedures in our patients with HD. METHODS: Retrospective data of 50 HD patients were analyzed. Of these patients, 25 underwent RB (2000-2006) and in 25 the TERPT was performed (2005-2009). Medical records were reviewed to score complications and outcomes. Differences were analyzed using Chi-Square and Mann-Whitney U tests. RESULTS: All RB patients (100%) were given a colostomy compared with four patients (16%) in the TERPT group (p < 0.001). The average age at surgery in the RB group was 191 days whereas this was 72 days in the TERPT group (p < 0.01). The mean length of time of surgery in the RB group (158 min) was not significantly different from that in the TERPT group (183 min). Ganglion cells were located in all specimens at the proximal end of the specimens. The median time to first feeding significantly decreased from 2 days (range 1-11) in the RB group to 1 day (range 1-3) in the TERPT group (p < 0.01). The median length of hospital stay decreased in the TERPT group (8 days) compared with the RB group (10 days) (p < 0.001). There was a significant reduction in postoperative obstructive symptoms during the first 6 months in the TERPT group (48%) compared with the RB group (84%) (p = 0.016). Postoperative enterocolitis decreased from 40% in the RB group to 24% in the TERPT group although this was not statistically significant. CONCLUSIONS: The introduction of TERPT reduced the need for colostomies; it shortened days to first feeding after surgery and reduced hospital stay. It also improved short-term outcome with less obstructive symptoms. We recommend TERPT surgery as a first choice in children with HD. we consider the RB now to be obsolete.1 november 201
Ectopic Lymphoid Structures Support Ongoing Production of Class-Switched Autoantibodies in Rheumatoid Synovium
Costantino Pitzalis and colleagues show that lymphoid structures in synovial tissue of patients with rheumatoid arthritis support production of anti-citrullinated peptide antibodies, which continues following transplantation into SCID mice
A study of the dry forest communities in the Dominican Republic
This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani (thorny dry forest on coastal dunes), Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest), Consoleo moniliformis-Camerarietum linearifoliae (dry forest on hard limestones), Lemaireocereo hystricis-Prosopidetum juliflorae (northern Dominican disturbed dry forest), Lycio americani-Prosopidetum juliflorae (disturbed dry forest on saline soils) and Guettardo ellipticae-Guapiretum discoloris (dry forest on flat-topped hillocks in Montecristi). This is an important step forward in the phytosociological and floristic studies of the Caribbean territories.Este trabalho apresenta um estudo florístico e fitossociológico das comunidades de florestas secas da República Dominicana. Um total de 69 amostras foram obtidas pelo método relevé em biótopos florestais secos. As amostras foram posteriormente submetidas à análise de correspondência destendenciada para a determinação e estudo de possíveis agrupamentos. O estudo não abrange formações arbóreas desenvolvidas sobre serpentinitos, nem as chamadas florestas semideciduais, peculiares às áreas de maior pluviosidade. Foram identificados nove fitocenoses. Os resultados mais significativos levaram à descrição de seis novas associações fitossociológicas: Simaroubetum berteroani (floresta espinhosa seca em dunas costeiras), Phyllostylo rhamnoidis-Prosopidetum juliflorae (floresta seca perturbada do sul da República Dominicana), Consoleo moniliformis-Camerarietum linearifoliae (floresta seca sobre calcários compactos), Lemaireocereo hystricis-Prosopidetum juliflorae (floresta seca perturbada do norte da República Dominicana), Lycio americani-Prosopidetum juliflorae (floresta seca perturbada desenvolvida em solos salinos) Guettardo ellipticae-Guapiretum discoloris (floresta seca em colinas de topo achatado em Montecristi). O trabalho realizado representa um importante avanço nos estudos fitossociológicos e florísticos dos territórios do Caribe.This research paper was possible thanks to the sponsorship of the Agencia Española de Cooperación Internacional para el Desarrollo (AECID), under the auspices of the Ministerio de Asuntos Exteriores y de Cooperación de España, which funded the project (cod. A/3499/05)
Parasites and immunotherapy: with or against?
Immunotherapy is a sort of therapy in which antibody or antigen administrates to the patient in order to treat or reduce the severity of complications of disease. This kind of treatment practiced in a wide variety of diseases including infectious diseases, autoimmune disorders, cancers and allergy. Successful and unsuccessful immunotherapeutic strategies have been practiced in variety of parasitic infections. On the other hand parasites or parasite antigens have also been considered for immunotherapy against other diseases such as cancer, asthma and multiple sclerosis. In this paper immunotherapy against common parasitic infections, and also immunotherapy of cancer, asthma and multiple sclerosis with parasites or parasite antigens have been reviewe
Origin and diversification of Xanthomonas citri subsp. citri pathotypes revealed by inclusive phylogenomic, dating, and biogeographic analyses.
Xanthomonas citri subsp. citri pathotypes cause bacterial citrus canker, being responsible for severe agricultural losses worldwide. The A pathotype has a broad host spectrum, while A* and Aw are more restricted both in hosts and in geography. Two previous phylogenomic studies led to contrasting well-supported clades for sequenced genomes of these pathotypes. No extensive biogeographical or divergence dating analytic approaches have been so far applied to available genomes. Results: Based on a larger sampling of genomes than in previous studies (including six new genomes sequenced by our group, adding to a total of 95 genomes), phylogenomic analyses resulted in different resolutions, though overall indicating that A?+?AW is the most likely true clade. Our results suggest the high degree of recombination at some branches and the fast diversification of lineages are probable causes for this phylogenetic blurring effect. One of the genomes analyzed, X. campestris pv. durantae, was shown to be an A* strain; this strain has been reported to infect a plant of the family Verbenaceae, though there are no reports of any X. citri subsp. citri pathotypes infecting any plant outside the Citrus genus. Host reconstruction indicated the pathotype ancestor likely had plant hosts in the family Fabaceae, implying an ancient jump to the current Rutaceae hosts. Extensive dating analyses indicated that the origin of X. citri subsp. citri occurred more recently than the main phylogenetic splits of Citrus plants, suggesting dispersion rather than host-directed vicariance as the main driver of geographic expansion. An analysis of 120 pathogenic-related genes revealed pathotype-associated patterns of presence/absence. Conclusions: Our results provide novel insights into the evolutionary history of X. citri subsp. citri as well as a sound phylogenetic foundation for future evolutionary and genomic studies of its pathotypes
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