958 resultados para spring to neap tide


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A series of HeLa cell lines which stably express beta-globin pre-mRNAs carrying point mutations at nt 654, 705, or 745 of intron 2 has been developed. The mutations generate aberrant 5' splice sites and activate a common 3' cryptic splice site upstream leading to aberrantly spliced beta-globin mRNA. Antisense oligonucleotides, which in vivo blocked aberrant splice sites and restored correct splicing of the pre-mRNA, revealed major differences in the sensitivity of these sites to antisense probes. Although the targeted pre-mRNAs differed only by single point mutations, the effective concentrations of the oligonucleotides required for correction of splicing varied up to 750-fold. The differences among the aberrant 5' splice sites affected sensitivity of both the 5' and 3' splice sites; in particular, sensitivity of both splice sites was severely reduced by modification of the aberrant 5' splice sites to the consensus sequence. These results suggest large differences in splicing of very similar pre-mRNAs in vivo. They also indicate that antisense oligonucleotides may provide useful tools for studying the interactions of splicing machinery with pre-mRNA.

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The aim of the present study was to analyse whether offspring of mature Quercus ilex trees grown under life-long elevated pCO2 show alterations in the physiological response to elevated pCO2 in comparison with those originating from mature trees grown at current ambient pCO2. To investigate changes in C- (for changes in photosynthesis, biomass and lignin see Polle, McKee & Blaschke Plant, Cell and Environment 24, 1075–1083, 2001), N-, and S-metabolism soluble sugar, soluble non-proteinogenic nitrogen compounds (TSNN), nitrate reductase (NR), thiols, adenosine 5′-phosphosulphate (APS) reductase, and anions were analysed. For this purpose Q. ilex seedlings were grown from acorns of mother tree stands at a natural spring site (elevated pCO2) and a control site (ambient pCO2) of the Laiatico spring, Central Italy. Short-term elevated pCO2 exposure of the offspring of control oaks lead to higher sugar contents in stem tissues, to a reduced TSNN content in leaves, and basipetal stem tissues, to diminished thiol contents in all tissues analysed, and to reduced APS reductase activity in both, leaves and roots. Most of the components of C-, N- and S-metabolism including APS reductase activity which were reduced due to short-term elevated pCO2 exposure were recovered by life-long growth under elevated pCO2 in the offspring of spring oaks. Still TSNN contents in phloem exudates increased, nitrate contents in lateral roots and glutathione in leaves and phloem exudates remained reduced in these plants. The present results demonstrated that metabolic adaptations of Q. ilex mother trees to elevated pCO2 can be passed to the next generation. Short- and long-term effects on source-to-sink relation and physiological and genetic acclimation to elevated pCO2 are discussed.

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Slow growth, branch dieback and scarce acorn yield are visible symptoms of decay in abandoned Quercus pyrenaica coppices. A hypothetical root-to-shoot (R:S) imbalance provoked by historical coppicing is investigated as the underlying driver of stand degradation. After stem genotyping, 12 stems belonging to two clones covering 81 and 16 m2 were harvested and excavated to measure above- and below-ground biomass and nonstructural carbohydrate (NSC) pools. To study root system functionality, root connections and root longevity were assessed by radiocarbon analysis. Seasonality of NSC was monitored on five additional clones. NSC pools, R:S biomass ratio and fine roots-to-foliage ratio were higher in the large clone, whose centennial root system, estimated to be 550 years old, maintained large amounts of sapwood (51.8%) for NSC storage. 248 root connections were observed within the large clone, whereas the small clone showed comparatively simpler root structure (26 connections). NSC concentrations were higher in spring (before bud burst) and autumn (before leaf fall), and lower in summer (after complete leaf expansion); they were always higher in roots than in stems or twigs. The persistence of massive and highly inter-connected root systems after coppicing may lead to increasing R:S biomass ratios and root NSC pools over time. We highlight the need of surveying belowground organs to understand aboveground dynamics of Q. pyrenaica, and suggest that enhanced belowground NSC storage and consumption reflect a trade-off between clonal vegetative resilience and aboveground performance.

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Subsurface fluid flow can be affected by earthquakes; increased spring activity, mud vol- cano eruptions, groundwater fluctuations, changes in geyser frequency, and other forms of altered subsurface fluid flow have been documented during, after, or even prior to seismic shaking. Recently discovered giant pockmarks on the bottom of Lake Neuchâtel, Switzerland, are the lake-floor expression of subsurface fluid flow. They discharge groundwater from the Jura Mountains karstic aquifers and experience episodically increased subsurface fluid flow documented by subsurface sediment mobilization deposits at the levees of the pockmarks. In this study, we present the spatio-temporal distribution of event deposits from these phases of sediment expulsion and of multiple time-correlative mass-transport deposits. We report five striking instances of concurrent multiple subsurface sediment deposits and multiple mass- transport deposits since late glacial times, for which we propose past earthquakes as a trigger. Comparison of this new event catalogue with historic earthquakes and other independent paleoseismic records suggests that initiation of sediment expulsion requires a minimum mac- roseismic intensity of VII. Thus, our study presents for the first time sedimentary deposits resulting from increased subsurface fluid flow as a paleoseismic proxy.

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Stable isotope analyses of discrete seasonal layers from a 108-yr annually laminated freeze-core from Baldeg-gersee, a small, eutrophic lake in central Switzerland, provide information on the climatological and environmental factors, including lake eutrophication, that control oxygen and carbon isotopic composition of epilimnic biologically induced calcite precipitate. During the last 100 yr, Baldeggersee has undergone major increases in productivity and eutrophication in response to nutrient loading from agriculture and industrialization in the lake's watershed. Calibration of the isotopic signal in Baldeggersee to historical limnological data quantitatively links evidence of isotopic depletion in the sedimented calcite to trophic state of the lake. δ18O values from the spring/summer “light” sediment layers steadily diverged to more depleted values in response to historical eutrophication: measured δ18O values were up to 21.5‰ more negative than calculated equilibrium δ18O values. Evidence for 13C depletion in the calcite, relative to equilibrium values, is more difficult to ascertain because of an overall dominance of isotopic enrichment in the dissolved inorganic pool as productivity in Baldeggersee increases. A positive association exists between the degree of oxygen-18 depletion and the calcite crystal size. Thus, large amorphous calcite grains can be used as a proxy for recognizing apparent isotopic nonequilibrium in sediment sequences from highly productive lacustrine environments from all geologic time scales. In contrast to the light layers, the oxygen isotopic composition of the calcite in the late summer/fall “dark” sediment layers is unaffected by the apparent isotope nonequilibrium. Oxygen and carbon isotope values from the dark laminae in the Baldeggersee sediment therefore provide environmental and climatological proxies that can be calibrated with known environmental and regional climate data for the last century.

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Abundance of the Ommastrephes bartramii winter-spring cohort fluctuated greatly from 1995 to 2004. To understand how abundance was influenced by sea surface conditions, we examined the variations in the proportion of thermal habitats with favourable sea surface temperature (SST). The SST data of both the spawning and feeding grounds were used to calculate the monthly proportion of favourable-SST areas (PFSSTA). Catch per fishing day per fishing boat (catch per unit effort, CPUE) of the Chinese mainland squid-jigging fleet was used as squid abundance index. The relationships between CPUE and monthly PFSSTA at spawning and feeding grounds were analyzed, and the relationship between CPUE and selected PFSSTA was quantified with a multiple linear regression model. Results showed that February PFSSTA at the spawning ground and August to November PFSSTA at the feeding ground could account for about 60% of the variability in O. bartramii abundance between 1995 and 2004, that February was the most important period influencing squid recruitment during the spawning season, and that feeding ground PFSSTA during the fishing season would influence CPUE by causing squid to aggregate. Our forecast model was found to perform well when we compared the model-predicted CPUEs and the average CPUEs observed during August to November in 2005 and 2006 from the Chinese squid-jigging fishery.

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Dimethylsulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP), in both particulate and dissolved forms, were surveyed during the early spring (March and April) and summer (July) of 1991 in coastal and offshore waters of the Gulf of Maine, USA, along with the hydrography, inorganic nutrients, phytoplankton chlorophyll, and phytoplankton taxonomic composition and abundance. Concentrations as high as 15 nM DMS (in April and July), 208 nM particulate DMSP (in April), and 101 nM dissolved DMSP (in July) were recorded. Total DMSP (dissolved plus particulate) reached 293 nM in a patch of the dinoflagellate Katodinium sp. in April. This is the first report of high DMSP concentrations in temperate waters in early spring associated with any organism other than the prymnesiophyte Phaeocystis pouchetii. There were no correlations between phytoplankton biomass, as measured by chlorophyll a, and DMS, and there were only slight correlations between chlorophyll a and DMSP in either dissolved or particulate form. As previously demonstrated by others, concentrations of intracellular (particulate) DMSP were related more to the presence of specific phytoplankton species rather than to overall phytoplankton biomass. The occurrence of high DMSP and DMS levels in early spring, comparable with or higher than those seen in summer maxima, at a time when bacterial activity is minimal and wind speeds are typically high may result in enhanced air-sea-fluxes of DMS.

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Despite the horrific oil spill in the Gulf and possible extinction of Kemp's Ridley sea turtles, there are still reasons to celebrate the shore--for example, Connecticut's shorebirds.

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Children and adults frequently skip breakfast and rates are currently increasing. In addition, the food choices made for breakfast are not always healthy ones. Breakfast skipping, in conjunction with unhealthy breakfast choices, leads to impaired cognitive functioning, poor nutrient intake, and overweight. In response to these public health issues, Skip To Breakfast, a behaviorally based school and family program, was created to increase consistent and healthful breakfast consumption among ethnically diverse fifth grade students and their families, using Intervention Mapping™. Four classroom lessons and four parent newsletters were used to deliver the intervention. For this project, a healthy, "3 Star Breakfast" was promoted, and included a serving each of dairy product, whole grain, and fruit, each with an emphasis on being low in fat and sugar. The goal of this project was to evaluate the feasibility and acceptability of the intervention. A pilot-test of the intervention was conducted in one classroom, in a school in Houston, during the Fall 2007 semester. A qualitative evaluation of the intervention was conducted, which included focus groups with students, phone interviews of parents, process evaluation data from the classroom teacher, and direct observation. Sixteen students and six parents participated in the study. Data were recorded and themes were identified. Initial results showed there is a need for such programs. Based on the initial feedback, edits were made to the intervention and program. Results showed high acceptability among the teacher, students, and parents. It became apparent that students were not reliably getting the parent newsletters to their parents to read, so a change to the protocol was made, in which students will receive incentives for having parents read newsletters and return signed forms, to increase parent participation. Other changes included small modifications to the curriculum, such as, clarifying instructions, changing in-class assignments to homework assignments, and including background reading materials for the teacher. The main trial is planned to be carried out in Spring 2008, in two elementary schools, utilizing four, fifth grade classes from each, with one school acting as the control and one as the intervention school. Results from this study can be used as an adjunct to the Coordinated Approach To Child Health (CATCH) program. ^

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Geographic health planning analyses, such as service area calculations, are hampered by a lack of patient-specific geographic data. Using the limited patient address information in patient management systems, planners analyze patient origin based on home address. But activity space research done sparingly in public health and extensively in non-health related arenas uses multiple addresses per person when analyzing accessibility. Also, health care access research has shown that there are many non-geographic factors that influence choice of provider. Most planning methods, however, overlook non-geographic factors influencing choice of provider, and the limited data mean the analyses can only be related to home address. This research attempted to determine to what extent geography plays a part in patient choice of provider and to determine if activity space data can be used to calculate service areas for primary care providers. ^ During Spring 2008, a convenience sample of 384 patients of a locally-funded Community Health Center in Houston, Texas, completed a survey that asked about what factors are important when he or she selects a health care provider. A subset of this group (336) also completed an activity space log that captured location and time data on the places where the patient regularly goes. ^ Survey results indicate that for this patient population, geography plays a role in their choice of health care provider, but it is not the most important reason for choosing a provider. Other factors for choosing a health care provider such as the provider offering "free or low cost visits", meeting "all of the patient's health care needs", and seeing "the patient quickly" were all ranked higher than geographic reasons. ^ Analysis of the patient activity locations shows that activity spaces can be used to create service areas for a single primary care provider. Weighted activity-space-based service areas have the potential to include more patients in the service area since more than one location per patient is used. Further analysis of the logs shows that a reduced set of locations by time and type could be used for this methodology, facilitating ongoing data collection for activity-space-based planning efforts. ^

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This study retrospectively evaluated the spatial and temporal disease patterns associated with influenza-like illness (ILI), positive rapid influenza antigen detection tests (RIDT), and confirmed H1N1 S-OIV cases reported to the Cameron County Department of Health and Human Services between April 26 and May 13, 2009 using the space-time permutation scan statistic software SaTScan in conjunction with geographical information system (GIS) software ArcGIS 9.3. The rate and age-adjusted relative risk of each influenza measure was calculated and a cluster analysis was conducted to determine the geographic regions with statistically higher incidence of disease. A Poisson distribution model was developed to identify the effect that socioeconomic status, population density, and certain population attributes of a census block-group had on that area's frequency of S-OIV confirmed cases over the entire outbreak. Predominant among the spatiotemporal analyses of ILI, RIDT and S-OIV cases in Cameron County is the consistent pattern of a high concentration of cases along the southern border with Mexico. These findings in conjunction with the slight northward space-time shifts of ILI and RIDT cluster centers highlight the southern border as the primary site for public health interventions. Finally, the community-based multiple regression model revealed that three factors—percentage of the population under age 15, average household size, and the number of high school graduates over age 25—were significantly associated with laboratory-confirmed S-OIV in the Lower Rio Grande Valley. Together, these findings underscore the need for community-based surveillance, improve our understanding of the distribution of the burden of influenza within the community, and have implications for vaccination and community outreach initiatives.^

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Background. First synthesized in 1874, dichlorodiphenyltrichloroethane (DDT) was not used until the second half of World War II after its insecticidal properties were discovered in 1939. For decades DDT has been used globally with the intent of eradicating malaria. This began in 1955 when the eighth World Health Assembly launched a global campaign selecting DDT as the chemical of choice for the eradication of malaria. The United States banned DDT use in 1972 partially due to the publication of “Silent Spring” by Rachel Carson in 1962 which suggested that DDT was harmful to the environment, wildlife and is a carcinogen. ^ Objectives. To critically review the literature on DDT, and evaluate its importance in malaria prevention and control. Methods: The design of this systematic literature review is a narrative summary and evaluation of the papers reviewed. The data came from searches using PubMed and MEDLINE which are free and publicly available databases. Inclusive criteria that were considered during the search are English language peer reviewed journal articles published in the last 20 years. The keywords were: “insecticidal and agricultural use of DDT”, “human impact of malaria”, “economic impact of malaria”, “benefits of DDT”, “effects of DDT”, “importance of malaria control”, and alternatives to DDT for malaria control. ^ Results. Malaria continues to be one of the most common infectious diseases and creates a tremendous global public health problem. WHO recommends DDT for malaria vector control because compared to other pesticides, it is the most persistent in indoor spraying. ^ Conclusion. Indoor spraying of DDT in malaria endemic areas may cause increased exposure of the chemical to humans; however I conclude that the overall benefits outweigh the risks because more lives are saved due to fewer infections with malaria.^

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If allowed to continue unabated, the obesity epidemic may lead to the first decline in life expectancy in the developed world (Olshansky et al., 2005). Similar to the relationship between smoking habits in youth and adulthood, obesogenic dietary and physical activity habits in childhood may persist into adulthood (Kelder et al., 2002). Teaching children how to establish healthy eating habits and activity levels, as well as providing them the necessary resources to internalize and maintain these behaviors, may be the key to curbing this epidemic.^ A school-based obesity prevention approach is advantageous for many reasons including exposure to large captive audiences, reduced costs of sustainability and long-term maintenance, and generalizability of models and results across multiple populations. The effectiveness of school-based programs has been researched over the past 20 years, with promising results.^ Social marketing is a program-planning process that “facilitates the acceptance, rejection, modification, abandonment, or maintenance of particular behaviors” (Grier & Bryant, 2005). Social marketing has been shown to be effective in a variety of public health applications including improving diet, increasing physical activity, and preventing substance abuse. It is hypothesized that social marketing could further enhance the effectiveness of the Coordinated Approach To Child Health (CATCH) Central Texas Middle School Project, a school-based obesity prevention program.^ The development, implementation, and initial evaluation of the get ur 60 campaign, to promote the Center for Disease Control and Prevention (CDC) recommended sixty minutes of daily activity, is described in this paper. Various components of the get ur 60 campaign were assessed to evaluate the effectiveness of the campaign during the first semester of implementation. At the end of the spring semester focus groups were held to collect student reactions to the first semester of the get ur 60 campaign.^ The initial results from the first semester of get ur 60 have demonstrated that the campaign as designed was feasible to implement, accepted at all intervention schools, and resulted in a measure of success. ^

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This culminating experience was a practice based intervention conducted by an organization, utilizing an intervention mapping approach for the program planning. It took place summer 2010 through spring 2011 and included incorporating a community garden into the Gusto wellness program at The Women's Home. This organization offers long-term residential care, and therapeutic services. Literature relating to community gardens and nutrition behavior change was reviewed. Short-term objectives included: 1) Conducting a needs assessment using focus groups, 2) Designing gardening program components based on intervention mapping guidelines, 3) Constructing a garden bed at Midtown Community Garden for use of The Women's Home, 4) Planning and implementing gardening education, and 5) Assessing feasibility of the garden program. The target population included 24 residents living at the residential dormitory of The Women's Home at the time of this project. The major variables are intervention mapping constructs including: 1) Needs assessment, 2) Preparing matrices of change objectives, 3) Selecting theory-informed intervention methods and practical strategies, 4) Producing program components and materials, 5) Planning program adoption, implementation, and sustainability, and 6) Planning for evaluation. The specific focus was lack of access to fresh fruits and vegetables (FV) for this population. Focus group responses revealed interest in community garden participation. Matrices of change were developed for lack of FV access based on performance objectives for behavioral and environmental factors and related determinants and theory. Methods and strategies were developed to implement a community garden and encourage participation. Program components included initiating a garden club, networking activities, creating gardening curriculum, and participating at Midtown Community Garden. Adoption and implementation performance objectives were outlined, and many were carried out. Evaluation questions were designed and outcomes of the garden project were discussed. ^ Outcomes of the project included exposure of garden topics and activities for The Women's Home residents, focus group responses revealing an interest in gardening among this population, gardening program components designed based on intervention mapping steps, and a constructed garden bed that was used for planting vegetables and flowers through fall 2010. Limited resources and budget along with a lack of a residential coordinator at The Women's Home were the main limiting factors for this project. Future garden projects can be developed using the intervention mapping process.^