120 research outputs found
Seedbed consolidation and surface sealing for soils of different texture and soil organic carbon contents
Effects of simulated rainfall intensity on water flow through soil in two tillage systems
Diffuse losses of phosphorus from agricultural land to freshwater reservoirs have gained increasing interest in later years. Resent research suggests that phosphorus is mainly transported from the fields through macropores, and that soil under reduced forms of tillage can develop a higher macroporosity and thus an increased risk of phosphorus leaching compared to conventionally tilled soil, because of the more rapid flows of water through the
soil. In this study field measurements of flow responses to variations in rainfall and laboratory measurements of soil dry bulk density, soil porosity and soil water retention characteristics were compared for a heavy clay soil subject to reduced and conventional tillage respectively.
In the field, rainfall with intensities of 10 or 33 mm/h were simulated and percolating water was collected from a cavity dug out at 40-45 cm depth and the collected
volume was measured at given times. A simple dual-permeability model was also made and its ability to describe flow responses to changes in rainfall intensity was evaluated through comparison with the field measurements. Flow responses to variations in rainfall
intensity were rather similar between the two tillage treatments. Stabilized outflow rates were also very similar between the treatments; between 4 and 8.5 mm/h under the lower rainfall intensity and between 22 and 28 mm/h under the higher. Neither of the parameters measured at the lab showed any clear differences between the two tillage treatments. The model was able to describe the timing of changes in outflow in response to changes in rainfall
intensity, but the simulated outflow rate was higher than what was measured and the model also described different final soil water contents after rainfall from those that were measured. Overall, the measurements did not show any effect of tillage treatment on soil hydraulic properties on the profile scale; flow showed dependence mainly on rainfall intensity and soil moisture conditions. The model would need to account for water flow from macropores to matrix to better be able to describe the total outflow from the profile
Surface and subsurface transport pathways for pesticides to surface waters
Risk assessment and mitigation of pesticides losses to surface waters is a major challenge due to spatial and temporal variation in the factors that influence underlying transport processes. This thesis examines effects of spatial and temporal variation in soil properties on such losses and the pathways along which the transport occurs. Spatial variation in pesticide concentrations in streamflow were monitored in a small Swedish agricultural catchment with a large variation in soil types. Temporal variability in the structural and hydraulic properties that largely control the partitioning between surface and subsurface runoff was examined through field measurements and laboratory experiments.
Considerable changes in the volume, size distribution and connectivity of structural pores due to rainfall were observed in the harrowed layer after tillage, both in the field and the laboratory. In the field these changes were associated with decreases in near-saturated hydraulic conductivities of around one order of magnitude. Effects of wetting and drying on total porosity and the pore size distribution (PSD) varied between soils of different texture and organic carbon content. Post-tillage changes in soil structural and hydraulic properties could be accounted for in mechanistic models as changes in total porosity and the PSD and functions relating soil properties to the magnitude of these changes should be useful for parameterization. The ability to predict pesticide losses through surface runoff could thus be expected to increase.
At the catchment scale, consistently larger numbers of compounds at larger concentrations were found in a sub-catchment with a relatively large proportion of clay soils than in a sub-catchment with a smaller proportion of such soils. Only a few compounds at trace concentration were found in a third sub-catchment with coarser textured soils. Temporal stability of this spatial pattern suggests that the relative risk of pesticide losses to surface waters is related to soil properties under Swedish agro-environmental conditions. Soil texture maps could thus be used as a simple method for identification of high-risk areas. In the studied catchment, which is to a large extent subsurface drained and where surface connectivity between fields and the stream is limited, drainage was found to be a more likely dominant transport pathway than surface runoff
Storage for water and plant nutrients
Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in the
distribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, while
farms with animal production often have manure in excess of their needs. In addition to this the retention of
water and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number and
size in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophication
as well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrich
surface water from agricultural areas and use it for irrigation of agricultural crops. This thesis is a study on
the water and nutrient flows between four irrigation ponds, the irrigated fields and the streams from which water
is pumped into storage. It was found that the amount of nitrogen (N) and phosphorus (P) that had been gathered
in the different ponds varied a lot between ponds, due to differences in nutrient levels in the streams and to
differences in when ponds were filled. A maximum of 98 kg of N and 0.4 kg of P were collected in one of the
ponds. Only small amounts of nutrients were brought back to the fields with irrigation, at the most 5 kg of N and
0.07 kg of P. It was concluded that the practice of irrigating agricultural crops with nutrient-rich surface water
did not contribute much to nutrient demand, but it decreased nutrient transport further downstream as effectively
as an average wetland
Desenvolvimento de um Guia de Cuidado FarmacĂȘutico para o atendimento de pacientes em tratamento da ansiedade
TCC (graduação) - Universidade Federal de Santa Catarina, Centro de CiĂȘncias da SaĂșde, FarmĂĄcia.A ansiedade Ă© uma condição clĂnica incapacitante no Brasil e no mundo. O tratamento adequado dessa condição requer o trabalho coordenado de uma equipe de profissionais. Falhas no cuidado podem levar a redução da qualidade de vida do paciente, ao agravamento dos quadros e maiores custos para o sistema de saĂșde e para a sociedade. Sabe-se que os tratamentos sĂŁo complexos e muitas vezes envolvem o uso de medicamentos. Neste contexto, destaca-se o papel do farmacĂȘutico na avaliação e acompanhamento dos tratamentos, visando Ă adesĂŁo aos tratamentos, e que estes sejam os mais efetivos e seguros possĂveis. Para tal, Ă© necessĂĄrio que estejam munidos de informação. Tendo isso em vista, o objetivo deste trabalho foi desenvolver um Guia de Cuidado FarmacĂȘutico para auxiliar no atendimento de pacientes em tratamento da ansiedade. Assim, realizou-se um estudo descritivo transversal, com estudo de campo, para levantamento de dados a respeito de quais informaçÔes os profissionais farmacĂȘuticos acreditam ser mais relevantes para constar no guia e quais suas dificuldades no atendimento destes pacientes. A partir disso, informaçÔes foram buscadas em diversas fontes de dados, como livros, artigos, bases de dados online, guidelines e protocolos nacionais e internacionais. O modelo de guia desenvolvido foi validado com farmacĂȘuticos com experiĂȘncia no atendimento de pacientes. O material final ficou dividido em 5 capĂtulos principais: tratamento da ansiedade, efetividade do tratamento, adesĂŁo ao tratamento, segurança do tratamento e comunicação com o paciente. Pretende-se que o guia elaborado sirva de instrumento de suporte, simples e organizado, para auxiliar no atendimento destes pacientes, no manejo adequado de possĂveis problemas identificados, na promoção de educação em saĂșde e para o uso racional de medicamentos, com vistas a melhores resultados terapĂȘuticos.Anxiety is a disabling clinical condition in Brazil and worldwide. Proper treatment of this condition requires the coordinated work of health care professionals. Failures in this system can lead to a reduction in the patient's quality of life, a worsening of clinical condition and causing higher costs for the healthcare system and for the society. It is known that treatments are complex and often involve the use of medication. In this context, the pharmacist's role is highlighted in the evaluation and follow-up of treatments, aiming at the adherence of treatments, and remaining as effective and safe as possible. For that, they need to be informed. The objective of this work was to develop a Pharmaceutical Care Guide to assist in the care of patients undergoing anxiety treatment. Therewith, a descriptive cross-sectional study with a field research, was carried out to collect data on what information pharmaceutical professionals believe to be most relevant to establish the guide and what are their difficulties in caring for these patients. From this, information was searched in data sources, such as books, articles, online databases, and national and international guidelines and protocols. The guide model developed was validated with pharmacists with experience in patient care. The final material is divided into 5 main chapters: anxiety treatment, treatment efficacy, treatment adherence, treatment safety and communication with the patient. It is intended that the guide will serve as a support tool, simple and organized, to assist in the care of these patients, in the adequate management of the possible problems identified, in the promotion of health education and the rational use of medicines, with a view to better therapeutic results
DepressĂŁo e pandemia: estudo com universitĂĄrios brasileiros
Depression is a disabling, chronic and recurrent disease. Symptoms include depressed mood, displeasure in activities that previously generated pleasure, loss or significant weight gain due to changes in appetite, insomnia or hypersomnia, lack of energy, y, guilt, difficulty concentrating, low self-esteem, irritability, anxiety, and , in severe cases, can lead to suicide. It can be classified as mild, moderate or severe according to the intensity of the symptoms. This disease can worsen in several contexts, such as in situations of social isolation, due to stress, anxiety, lack or excess information. College students are affected due to the change in routine and psychological pressure. The objective of the work was to evaluate the number of university students with symptoms of depression, comparing courses in the health field with those in other areas. The research had a sample of 210 university students from the state of Rio de Janeiro, Brazil, 69% female and 31% male, with an average age of 23 years. The questionnaire was sent via social network containing: a form evaluating personal data and the Beck Depression Inventory (BDI). In relation to university students, the BDI showed that 119 (56.7%) had no symptoms, 20 (9.5%) had dysphoria and 61 (29%) had symptoms of depression. It is concluded that the data indicated high rates of depressive symptoms among the university students studied and the need for follow-up actions.A depressĂŁo Ă© uma doença incapacitante, crĂŽnica e recorrente. Tem como sintomas humor deprimido, desprazer em atividades que antes geravam prazer, perda ou ganho significativo de peso por alteração no apetite, insĂŽnia ou hipersonia, falta de energia, sentimento de culpa, dificuldade de se concentrar, baixa autoestima, irritabilidade, ansiedade, e, em casos graves, pode levar ao suicĂdio. Pode ser classificadas como leve, moderada ou grave de acordo com a intensidade dos sĂntomas. Essa doença pode piorar em diversos contextos, como em situaçÔes de isolamento social, devido ao estresse, ansiedade, falta ou excesso de informação. Os universitĂĄrios sĂŁo afetados devido a mudança na rotina e a pressĂŁo psicolĂłgica. O objetivo do trabalho foi avaliar a quantidade de universitĂĄrios com sintomas de depressĂŁo, comparando cursos da ĂĄrea da saĂșde com o de outras ĂĄreas. A pesquisa teve uma amostra de 210 universitĂĄrios do estado do Rio de Janeiro, Brasil, sendo 69% do gĂȘnero feminino e 31% masculino, com idade mĂ©dia de 23 anos. O questionĂĄrio foi enviado via rede social contendo: um formulĂĄrio avaliando dados pessoais e o InventĂĄrio de DepressĂŁo de Beck (BDI). O BDI mostrou em relação aos universitĂĄrios que 119 (56.7%) nĂŁo apresentaram sintomas, 20 (9.5%) apresentaram disforia e 61 (29%) apresentaram sintomas de depressĂŁo. onclui-se que os dados indicaram altas taxas de sintomas depressivos entre os universitĂĄrios estudados e a necessidade de açÔes de acompanhamento
Earthworm burrowing modes and rates depend on earthworm species and soil mechanical resistance
Earthworms drive multiple soil processes, but their specific impact on soil functions differs between earthworm species and ecological categories. A key challenge in modern agriculture is soil compaction due to heavy ma-chinery, but we have limited quantitative knowledge about how the burrowing activity of different earthworm species is affected by compaction. Here, we address this question in a laboratory experiment with 2-D terraria, where we used Aporrectodea caliginosa (Savigny, 1826) and Aporrectodea longa (Ude, 1885) as representatives of two different ecological categories. We exposed both species to four different soil mechanical resistance levels and monitored their burrowing activity for three days. We quantified burrowing rates and cast production, assessed the burrowing mode, and estimated energy requirements as a function of soil mechanical resistance. The results showed that the burrowing rates of both earthworm species significantly decreased with increasing soil mechanical resistance, but that the impact was species-dependent and lower for A. longa. Earthworms changed their burrowing mode towards ingestion when soil mechanical resistance increased, and this shift was more prominent for A. caliginosa that primarily burrowed via cavity expansion (i.e. by pushing soil aside) at low soil mechanical resistance. We further show that energy requirement and cast produced per unit burrow length increased with soil mechanical resistance. Our study revealed significant and species-dependent adverse effects of soil mechanical resistance on earthworm burrowing, which in turn has consequences for many soil processes mediated by earthworms, such as water infiltration, soil aeration, nutrient cycling and soil organic matter turnover
Changing Neighborhoods and Residentsâ Health Perceptions: The Heart Healthy Hoods Qualitative Study
Cities, and therefore neighborhoods, are under constant change. Neighborhood changes may affect residentsâ health in multiple ways. The Heart Healthy Hoods (HHH) project studies the association between neighborhood and residentsâ health. Focusing on a middleâlow-socioeconomic neighborhood in Madrid (Spain), our aim was to describe qualitatively its residentsâ perceptions on the urban changes and their impacts on health. We designed a qualitative study using 16 semi-structured interviews including adult residents and professionals living or working in the area. Firstly, we described the perceived main social and neighborhood changes. Secondly, we studied how these neighborhood changes connected to residentsâ health perceptions. Perceived major social changes were new demographic composition, new socioâcultural values and economic changes. Residentsâ negative health perceptions were the reduction of social relationships, increase of stress and labor precariousness. Positive health perceptions were the creation of supportive links, assimilation of self-care activities and the change in traditional roles. Neighborhood changes yielded both negative and positive effects on residentsâ health. These effects would be the result of the interrelation of different elements such as the existence or absence of social ties, family responsibilities, time availability, economic resources and access and awareness to health-promoting programs. These qualitative research results provide important insight into crafting urban health policies that may ultimately improve health outcomes in communities undergoing change
Variation i biologisk mÄngfald och samhÀllsstruktur hos bottenfauna och kiselalger i tvÄ smÄ avrinningsomrÄden
Cirka 90% av Sveriges vattendrag avvattnar avrinningsomrĂ„den mindre Ă€n 15 km2. För dessa smĂ„ vattendrag finns ytterst begrĂ€nsad kunskap om biologi, kemi och hydrologi. Dessutom saknas information om aktuell status och mĂ€nsklig pĂ„verkan enligt EU:s vattendirektiv och de nationella bedömningsgrunderna. Normal provtagning av biologi i vattendrag sker pĂ„ lokaler dĂ€r avrinningsomrĂ„dets storlek överskrider 15 kmÂČ men vi vet lite om dessa prov ocksĂ„ representerar status och mĂ€nsklig pĂ„verkan för de uppströms liggande smĂ„ vattendragen. Att det finns eventuella skillnader biologiskt mellan smĂ„ och större vattendrag beror givetvis inte pĂ„ avrinningsomrĂ„dets storlek, utan att denna variabel Ă€r korrelerad med ekologiskt viktiga styrvariabler sĂ„som vattenkemi (hĂ€r frĂ€mst surhet), substrattyp och strömhastighet. För att anvĂ€nda en enhetlig klassificering i denna rapport delades vattendragen upp i storleksklasser dĂ€r provtagningslokalerna klassades som smĂ„ < 2 km2, medelstora 2 â 10 km2 och stora > 10 km2. I studien provtogs totalt 18 stationer med avseende pĂ„ biologi i tvĂ„ avrinningsomrĂ„den (DanshytteĂ„n och LugnĂ„n). Kemiskt skiljer sig bĂ„de avrinningsomrĂ„dena och de tre storleksklasserna Ă„t, framförallt nĂ€r det gĂ€ller de surhetsrelaterade parametrarna. MedelvĂ€rdet för antalet taxa av bottenfauna i de smĂ„ vattendragen var lĂ€gre Ă€n i de medelstora som i sin tur var lĂ€gre Ă€n i de stora vattendragen. Det fanns inget samband (korrelation) mellan avrinningsomrĂ„dets storlek och antalet taxa av bottenfauna. Det var ingen skillnad i antalet rĂ€knade taxa mellan de olika vattendragsstorlekarna för kiselalger. Det fanns inte heller nĂ„got samband (korrelation) mellan antalet rĂ€knade kiselalgstaxa och avrinningsomrĂ„dets storlek. För bĂ„de bottenfauna och kiselalger fanns en statistiskt sĂ€kerstĂ€lld skillnad i artsammansĂ€ttning mellan de tre storleksklasserna av avrinningsomrĂ„den. För kiselalger berodde detta frĂ€mst pĂ„ att de smĂ„ vattendragen Ă€r sura, och i dessa hittades surhetsrelaterade taxa, till skillnad frĂ„n de neutrala (oftast större) vattendragen. För bĂ„de bottenfauna och kiselalger klassades i princip alla lokaler som hög/god ekologisk status. Ett viktigt resultat frĂ„n studien Ă€r att de nedströms liggande provtagningslokalerna i denna studie inte pĂ„ ett tillfredsstĂ€llande sĂ€tt kunde pĂ„visa pĂ„verkan högre upp i avrinningsomrĂ„det (gĂ€ller frĂ€mst pH) dĂ€r de nedströms liggande lokalerna klassas som nĂ€ra neutrala eller neutrala medan de smĂ„ vattendragen uppströms klassas som sura eller mycket sura. Det fanns dĂ€remot inte nĂ„got samband mellan nĂ„got index (bottenfauna och kiselalger) och totalkvĂ€vehalt i vattendragen medan DJ indexet svarade bĂ€st mot totalfosfor gradienten i analysen av de tvĂ„ avrinningsomrĂ„dena tillsammans. ACID indexet för kiselalger svarade bĂ€ttre Ă€n MISA indexet mot pH gradienten i de tvĂ„ avrinningsomrĂ„dena tillsammans. Slutsatser: Det Ă€r frĂ€mst tre saker som behöver göras för att utöka vĂ„r förstĂ„else för och kunskap om de smĂ„ vattendragen: i) en provtagningsmetod för bottenfauna som ger jĂ€mförbara resultat med den standardiserade sparkprovtagningen bör utvecklas (troligtvis genom att man istĂ€llet för att ta fem enmetersprov, tar ett större antal prov med en surberliknande provtagare, men dĂ€r den totala provtagna ytan motsvarar de 1.25 m2 som Ă€r den yta som provtas enligt den standardiserade sparkprovtagning), ii) en större jĂ€mförelse mellan artsammansĂ€ttning av bottenfauna och kiselalger i uppströms liggande smĂ„vattendrag och nedströms större vattendrag bör genomföras dĂ€r i första hand opĂ„verkade vattendrag provtas för att se vilken effekt storlek av vattendragen har pĂ„ den biologiska mĂ„ngfalden och artsammansĂ€ttningen nĂ€r man inte behöver ta hĂ€nsyn till olika typer av mĂ€nsklig pĂ„verkan (opĂ„verkat tillstĂ„nd), iii) smĂ„ vattendrag bör i nĂ„gra fall inkluderas i den nationella miljöövervakningen (trendstationer) för att vi skall fĂ„ en uppfattning om vilken variation i artsammansĂ€ttning och biologisk mĂ„ngfald det finns i dessa smĂ„ system jĂ€mfört med större vattendrag (de Ă€r ju t.ex. i mycket högre utstrĂ€ckning Ă€n större vattendrag utsatta för risken för uttorkning respektive bottenfrysning jĂ€mfört med de större vattendrage
Thyroid hormones in relation to toxic metal exposure in pregnancy, and potential interactions with iodine and selenium
Background: Several endocrine-disrupting metals may affect thyroid function, but the few available studies of exposure during pregnancy and thyroid hormones are inconclusive. Objective: To explore if environmental exposure to cadmium (Cd), lead (Pb), and methylmercury (MeHg) impacts thyroid function in pregnancy, and interacts with iodine and selenium status. Methods: Women in a Swedish birth cohort provided blood and urine samples in early third trimester. Concentrations of erythrocyte Cd, Pb, and Hg (n = 544), urinary Cd and iodine (n = 542) and plasma selenium (n = 548) were measured using inductively coupled plasma-mass spectrometry. Free and total thyroxine (fT4, tT4) and triiodothyronine (fT3, tT3), and thyroid stimulating hormone (TSH), were measured in plasma (n = 548) with electrochemiluminescence immunoassays. Metal-hormone associations were assessed in regression models, and metal mixture effects and metal-nutrient interactions were explored in Bayesian kernel machine regression (BKMR). Results: In multivariable-adjusted regression models, a doubling of urinary Cd was associated with a mean increase in tT4 of 2.7 nmol/L (95% CI: 0.78, 4.6), and in fT3 and tT3 of 0.06 pmol/L (0.02, 0.10) and 0.09 nmol/L (0.05, 0.13), respectively. A doubling of urinary Cd was associated with a â0.002 (â0.003, â0.001) and â0.03 (â0.05, â0.02) decrease in the fT4:tT4 and fT3:tT3 ratio, respectively. A doubling of erythrocyte Hg (>1 \ub5g/kg) was associated with a decrease in fT3 and tT3 by â0.11 pmol/L (â0.16, â0.05) and â0.11 nmol/L (â0.16, â0.06), respectively, and a â0.013 (â0.02, â0.01) decrease in the fT3:fT4 ratio. BKMR did not indicate any mixture effect of toxic metals or interactions between metals and iodine or selenium in relation to the hormones. Conclusion: Our findings suggest that exposure to Cd and Hg, at levels globally prevalent through the diet, may affect thyroid function during pregnancy, independently of iodine and selenium levels. Further studies on potential implications for maternal and child health are warranted
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