469 resultados para Abstinence Survivorship


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The Comprehensive Everglades Restoration Plan (CERP) attempts to restore hydrology in the Northern and Southern Estuaries of Florida. Reefs of the Eastern oyster Crassostrea virginica are a dominant feature of the estuaries along the Southwest Florida coast. Oysters are benthic, sessile, filter-feeding organisms that provide ecosystem services by filtering the water column and providing food, shelter and habitat for associated organisms. As such, the species is an excellent sentinel organism for examining the impacts of restoration on estuarine ecosystems. The implementation of CERP attempts to improve: the hydrology and spatial and structural characteristics of oyster reefs, the recruitment and survivorship of C. virginica, and the reef-associated communities of organisms. This project links biological responses and environmental conditions relative to hydrological changes as a means of assessing positive or negative trends in oyster responses and population trends. Using oyster responses, we have developed a communication tool (i.e., Stoplight Report Card) based on CERP performance measures that can distinguish between responses to restoration and natural patterns. The Stoplight Report Card system is a communication tool that uses Monitoring and Assessment Program (MAP) performance measures to grade an estuary's response to changes brought about by anthropogenic input or restoration activities. The Stoplight Report Card consists of both a suitability index score for each organism metric as well as a trend score (− decreasing trend, +/− no change in trend, and + increasing trend). Based on these two measures, a component score (e.g., living density) is calculated by averaging the suitability index score and the trend score. The final index score is obtained by taking the geometric score of each component, which is then translated into a stoplight color for success (green), caution (yellow), or failure (red). Based on the data available for oyster populations and the responses of oysters in the Caloosahatchee Estuary, the system is currently at stage “caution.” This communication tool instantly conveys the status of the indicator and the suitability, while trend curves provide information on progress towards reaching a target. Furthermore, the tool has the advantage of being able to be applied regionally, by species, and collectively, in concert with other species, system-wide.

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Questions: How are the early survival and growth of seedlings of Everglades tree species planted in an experimental setting on artificial tree islands affected by hydrology and substrate type? What are the implications of these responses for broader tree island restoration efforts? Location: Loxahatchee Impoundment Landscape Assessment (LILA), Boynton Beach, Florida, USA. Methods: An experiment was designed to test hydrological and substrate effects on seedling growth and survivorship. Two islands – a peat and a limestone-core island representing two major types found in the Everglades – were constructed in four macrocosms. A mixture of eight tree species was planted on each island in March of 2006 and 2007. Survival and height growth of seedlings planted in 2006 were assessed periodically during the next two and a half years. Results: Survival and growth improved with increasing elevation on both tree island substrate types. Seedlings' survival and growth responses along a moisture gradient matched species distributions along natural hydrological gradients in the Everglades. The effect of substrate on seedling performance showed higher survival of most species on the limestone tree islands, and faster growth on their peat-based counterparts. Conclusions: The present results could have profound implications for restoration of forests on existing landforms and artificial creation of tree islands. Knowledge of species tolerance to flooding and responses to different edaphic conditions present in wetlands is important in selecting suitable species to plant on restored tree islands

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The present study has the primary aim of examining the predictors of treatment attrition among racial/ethnic minority adolescents with substance use problems. This study explores the potential differential influence of specific individual, social, cultural, and treatment factors on treatment attrition within three racial/ethnic subgroups of adolescents. Participants: A unique feature of the study is the use of a racial/ethnic minority sample (N=453), [U.S.-born Hispanics (n = 262), Foreign-born Hispanics (n = 117), and African-Americans (n = 74)]. Multivariate logit analyses were used to examine the influence of specific factors on treatment attrition among the full sample of adolescents, as well as within each racial/ethnic subgroup. Consistent with expectations, multivariate logit analyses reveal that, the specific factors associated with attrition varied across the three racial/ethnic subgroups. Having parents with problem substance use, being on the waitlist, and being court mandated to treatment emerged as predictors of attrition among the US-born Hispanics, while only Conduct Disorder was significantly associated with greater attrition among foreign-born Hispanics. Finally, among African-Americans, parental crack/cocaine use, parental abstinence from alcohol, and being on the waitlist were predictive of attrition. Multiple factors were associated with treatment attrition among racial/ethnic minority adolescents with specific factors differentially predicting attrition within each racial/ethnic subgroup. African-American youth were more than twice as likely as their Hispanic counterparts to leave treatment prematurely. It is critically important to understand the predictors of attrition among racial/ethnic minority youth in order to better meet the needs of youth most at risk of dropping out. ^

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Short-hydroperiod Everglades wetlands have been disproportionately affected by reductions in freshwater inflows, land conversion and biotic invasions. Severe hydroperiod reductions in these habitats, including the Rocky Glades, coupled with proximity to canals that act as sources of invasions, may limit their ability to support high levels of aquatic production. We examined whether karst solution holes function as dry-down refuges for fishes, providing a source of marsh colonists upon reflooding, by tracking fish abundance, nonnative composition, and survival in solution holes throughout the dry season. We paired field surveys with an in situ nonnative predation experiment that tested the effects of predation by the recent invader, African jewelfish (Hemichromis letourneuxi) on native fishes. Over the 3 years surveyed, a large number of the solution holes dried before the onset of the wet season, while those retaining water had low survivorship and were dominated by nonnatives. In the experiment, mortality of eastern mosquitofish (Gambusia holbrooki) in the presence of African jewelfish was greater than that associated with deteriorating water quality. Under current water management, findings suggest that solution holes are largely sinks for native fishes, given the high frequency of drydown, extensive period of fish residence, and predation by nonnative fishes.

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Every year, 16 million women aged 15 to 19 years give birth globally. Adolescent births account for 11% of all births globally and 23% of the overall burden of disability and diseases due to pregnancy and childbirth. In the United States, 750,000 adolescents (15-19 years) become pregnant each year, making the United States the developed country with the highest rates of adolescent pregnancy. The economic burden of adolescent pregnancy in the U. S. is $7-15 billion per year. Adolescent pregnancy brings risks associated with pregnancy induced hypertension, preterm infants, maternal and neonatal mortality. Social factors include poverty, low educational levels, alcohol, and drug use. Between 30-50% of adolescent mothers who have a first birth before age 18 years will have a second child within 12 to 24 months. Subsequent adolescent pregnancies compound fetal and maternal risks. Many vulnerable adolescent mothers succumb to external pressures and have a repeat adolescent pregnancy while others are able to overcome the challenges of an adolescent pregnancy and prevent a repeat adolescent pregnancy. This cross sectional survey designed study investigated the effects of resilience and social influences on contraceptive use or abstinence by Black and Hispanic adolescent parenting mothers to prevent a repeat adolescent pregnancy. 140 adolescent mothers were recruited from three postpartum units of a tertiary hospital system in Miami, Florida. The Wagnild and Young Resilience Scale and the Adolescent Social Influence Scale were used to measure resilience and social influences, respectively. Demographic data, length of labor, plan for contraceptive use or abstinence were measured by an investigator developed instrument. Point biserial correlation showed a significant positive correlation between Black adolescent mothers' resilience and contraceptive use (r =.366, p2(11, N=133) = 27.08, p =.004. (OR = .28). These results indicate a need for interventional strategies to maximize resilience in parenting adolescents to prevent a repeat adolescent pregnancy.

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The present study has the primary aim of examining the predictors of treatment attrition among racial/ethnic minority adolescents with substance use problems. This study explores the potential differential influence of specific individual, social, cultural, and treatment factors on treatment attrition within three racial/ethnic subgroups of adolescents. Participants: A unique feature of the study is the use of a racial/ethnic minority sample (N=453), [U.S.-born Hispanics (n = 262), Foreign-born Hispanics (n = 117), and African- Americans (n = 74)]. Multivariate logit analyses were used to examine the influence of specific factors on treatment attrition among the full sample of adolescents, as well as within each racial/ethnic subgroup. Consistent with expectations, multivariate logit analyses reveal that, the specific factors associated with attrition varied across the three racial/ethnic subgroups. Having parents with problem substance use, being on the waitlist, and being court mandated to treatment emerged as predictors of attrition among the US-born Hispanics, while only Conduct Disorder was significantly associated with greater attrition among foreign-born Hispanics. Finally, among African-Americans, parental crack/cocaine use, parental abstinence from alcohol, and being on the waitlist were predictive of attrition. Multiple factors were associated with treatment attrition among racial/ethnic minority adolescents with specific factors differentially predicting attrition within each racial/ethnic subgroup. African-American youth were more than twice as likely as their Hispanic counterparts to leave treatment prematurely. It is critically important to understand the predictors of attrition among racial/ethnic minority youth in order to better meet the needs of youth most at risk of dropping out.

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In aquatic ecosystems, hydrological fluctuation may generate a gradient of lifehistory responses associated with marsh drying. This study was conducted in the Florida Everglades to document spatial and temporal variability in growth and survivorship of the bluefin killifish (Lucania goodei) from six populations along a hydroperiod gradient. The otolith-microstructure analysis of field-collected fish was used to estimate growth rate and those data were combined with field-density estimates for survivorship analysis. Otolith analysis revealed that L. goodei is extremely short-lived with no variation in growth rates and very little spatial or temporal variation in survivorship. These results suggest that bluefin killifish populations experience similar life histories across a diversity of hydroperiods either through well-mixed populations homogenizing these vital rates, or more likely, that a multitude of factors force L. goodei to respond to these "stressors" in a similar fashion across hydroperiod gradients.

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Ethanol withdrawn individuals present a wealth of signs and symptoms, some of them related with anxiety. To better understand brain areas involved in anxiety caused by ethanol abstinence, preclinical studies have been employing models of ethanol consumption followed by withdrawal in rodents submitted to behavioral tests of anxiety, such as the elevated plus-maze. The aim of this study was to investigate if short- or long-term ethanol withdrawal could alter both anxiety-related behaviors in the elevated plus-maze (EPM) and open field tests and the number of serotonin immunorreactive cels in the dorsal raphe nucleus, a midbrain area associated with anxiety. Female Wistar rats (90 days old) were submitted to increasing concentrations of ethanol (2% for 3 days, 4% for 3 days and 6% for 15 days) as the only source of liquid diet and the control group received water ad libitum. Both groups received food ad libitum. In the behavioral experiments, on 21st day of consumption, ethanol was substituted by water (withdrawal) and 72 h or 21 days after withdrawal animals were submitted to the EPM, where it was evaluated the percentage of time and entries in the open arms and the entries in the enclosed arms during 5 minutes. Twenty and four hours after testing in the EPM, animals were submitted to the open field test for 15 minutes, where the distance traveled by the animals was observed along this period. During the first 5 minutes, the distance traveled, entries and time spent in the center of the test were analyzed. In the immunohistochemistry study, animals were submitted to 21 days of consumption of ethanol followed or not by 72 hours and 21 days of withdrawal previously perfusion, brain tissue preparation and quantification of serotonin dyed cells in the dorsal and caudal portions in the dorsal raphe nucleus. Behavioral data showed that both short- and long-term ethanol withdrawals reduced the open arms exploration in the EPM. In the open field test there were no locomotor activity changes during the total 15 minutes; however, longterm ethanol withdrawal reduced the exploration in the center of the open field during the first 5 minutes. In the immunohistochemistry step, there were no differences, when short- and long-term withdrawn groups were compared with control group; nevertheless, the chronic consumption of ethanol decreased the number of serotonergic immunorreactive cells in the dorsal part of dorsal raphe nucleus. Taken together, results here obtained suggest that both short- and long-term ethanol withdrawals promoted an anxiogenic-like effect that was not related with changes in the serotonin immunorreactivity in the dorsal and caudal parts of the dorsal raphe nucleus.

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Consensus has not been reached on safe alcohol consumption recommendations during pregnancy. The National Institutes for Care and Health Excellence (NICE) in the UK suggest that one to two drinks not more than twice per week is safe. However, the speech and language effects of even low levels of alcohol use among offspring are unknown. The aim of this study was to review systematically the evidence on studies of the effect of low to moderate levels of alcohol consumption during pregnancy (up to 70 grams of alcohol per week) compared to abstinence on speech and language outcomes in children.

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We present experiments that examined the metamorphosis, growth, and survivorship of larvae from three species of commercially and ecologically valuable shellfish (Mercenaria mercenaria, Argopecten irradians, and Crassostrea virginica) at the levels of CO2 projected to occur during the 21st century and beyond. Under CO2 concentrations estimated to occur later this century (~66 Pa, 650 ppm), M. mercenaria and A. irradians larvae exhibited dramatic declines (>50%) in survivorship as well as significantly delayed metamorphosis and significantly smaller sizes. Although C. virginica larvae also experienced lowered growth and delayed metamorphosis at ~66 Pa CO2, their survival was only diminished at ~152 Pa CO2. The extreme sensitivity of larval stages of shellfish to enhanced levels of CO2 indicates that current and future increases in pelagic CO2 concentrations may deplete or alter the composition of shellfish populations in coastal ecosystems.

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Manipulative studies have demonstrated that ocean acidification (OA) is a threat to coral reefs, yet no experiments have employed diurnal variations in pCO2 that are ecologically relevant to many shallow reefs. Two experiments were conducted to test the response of coral recruits (less than 6 days old) to diurnally oscillating pCO2; one exposing recruits for 3 days to ambient (440 µatm), high (663 µatm) and diurnally oscillating pCO2 on a natural phase (420-596 µatm), and another exposing recruits for 6 days to ambient (456 µatm), high (837 µatm) and diurnally oscillating pCO2 on either a natural or a reverse phase (448-845 µatm). In experiment I, recruits exposed to natural-phased diurnally oscillating pCO2 grew 6-19% larger than those in ambient or high pCO2. In experiment II, recruits in both high and natural-phased diurnally oscillating pCO2 grew 16 per cent larger than those at ambient pCO2, and this was accompanied by 13-18% higher survivorship; the stimulatory effect on growth of oscillatory pCO2 was diminished by administering high pCO2 during the day (i.e. reverse-phased). These results demonstrate that coral recruits can benefit from ecologically relevant fluctuations in pCO2 and we hypothesize that the mechanism underlying this response is highly pCO2-mediated, night-time storage of dissolved inorganic carbon that fuels daytime calcification.

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Invasive species allow an investigation of trait retention and adaptations after exposure to new habitats. Recent work on corals from the Gulf of Aqaba (GoA) shows that tolerance to high temperature persists thousands of years after invasion, without any apparent adaptive advantage. Here we test whether thermal tolerance retention also occurs in another symbiont-bearing calcifying organism. To this end, we investigate the thermal tolerance of the benthic foraminifera Amphistegina lobifera from the GoA (29° 30.14167 N 34° 55.085 E) and compare it to a recent "Lessepsian invader population" from the Eastern Mediterranean (EaM) (32° 37.386 N, 34°55.169 E). We first established that the studied populations are genetically homogenous but distinct from a population in Australia, and that they contain a similar consortium of diatom symbionts, confirming their recent common descent. Thereafter, we exposed specimens from GoA and EaM to elevated temperatures for three weeks and monitored survivorship, growth rates and photophysiology. Both populations exhibited a similar pattern of temperature tolerance. A consistent reduction of photosynthetic dark yields was observed at 34°C and reduced growth was observed at 32°C. The apparent tolerance to sustained exposure to high temperature cannot have a direct adaptive importance, as peak summer temperatures in both locations remain <32°C. Instead, it seems that in the studied foraminifera tolerance to high temperature is a conservative trait and the EaM population retained this trait since its recent invasion. Such pre-adaptation to higher temperatures confers A. lobifera a clear adaptive advantage in shallow and episodically high temperature environments in the Mediterranean under further warming.

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The literature on niche separation and coexistence between species is large, but there is widespread variation in behavioural strategy between individuals of the same species that has received much less attention. Understanding what maintains this diversity is important because intraspecific behavioural diversity can affect population dynamics and community interactions. Multiple behavioural strategies can arise either as phenotype-dependent ‘conditional strategies’, where phenotypic variation causes individuals to adopt different strategies for optimizing fitness, or as internally-independent ‘alternative strategies’, where multiple fitness peaks exist for individuals and strategic ‘choice’ remains plastic. Though intraspecific variation in stable phenotypes is known to maintain intraspecific behavioural diversity through conditional strategies, when internal conditions are highly plastic or reversible, it is not clear whether individual behaviours are maintained as conditional strategies, or as alternative strategies of equal fitness. In this study, I combine an observational and experimental approach to identify the likely mechanisms maintaining behavioural diversity between hemoglobin-rich and hemoglobin-poor morphs in a natural population of Daphnia pulicaria. In Round Lake, individuals with low hemoglobin migrate daily from the hypolimnion to the epilimnion, whereas individuals with high hemoglobin remain in the hypolimnion. Using high-resolution depth and time sampling, I discovered behavioural diversity both within and among hemoglobin phenotypes. I tested the role of hemoglobin phenotype in maintaining behavioural diversity using automated migration robots that move individuals across the natural environmental gradients in the lake. By measuring the fitness of each morph undergoing either a natural migration behaviour, or the migration of the opposite morph, I found that the fitness of hemoglobin rich and poor morphs in their natural behaviour does not differ, but that Hb-rich individuals can obtain equal fitness from either behaviour, while Hb-poor morphs suffer substantial drops in survivorship in the alternate migration behaviour. Thus, migration behaviour in this system exists as a conditional strategy for some individuals, and as alternative strategies of equal fitness for others. The results of this study suggest that individual limits in the expression of highly flexible internal conditions can reinforce intraspecific behavioural diversity. Few studies have measured the fitness consequences of switching migration strategies and this study provides a rare example in the field.

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BACKGROUND: Follow-up care aims to provide surveillance with early detection of recurring cancers and to address treatment complications and other health issues in survivorship. It is assumed that follow-up care fulfills these aims, however little evidence supports routine surveillance detecting curable disease early enough to improve survival. Cancer survivors are a diverse patient population, suggesting that a single follow-up regimen may not meet all patients’ follow-up needs. Little is known about what effective follow-up care should include for head and neck cancer patients in a Canadian setting. Identification of subgroups of patients with specific needs and current practices would allow for hypotheses to be generated for enhancing follow-up care. OBJECTIVES: 1a) To describe the follow-up needs and preferences of head and neck cancer patients, 1b) to identify which patient characteristics predict needs and preferences, 1c) to evaluate how needs and preferences change over time, 2a) to describe follow-up care practices by physician visits and imaging tests, and 2b) to identify factors associated to the delivered follow-up care. METHODS: 1) 175 patients who completed treatment between 2012 and 2013 in Kingston and London, Ontario were recruited to participate in a prospective survey study on patients’ needs and preferences in follow-up care. Bivariate and multivariate analyses were employed to describe patient survey responses and to identify patient characteristics that predicted needs and preferences. 2) A retrospective cohort study of 3975 patients on routine follow-up from 2007 to 2015 was carried out using data linkages across registry and administrative databases to describe follow-up practices in Ontario by visits and tests. Multivariate regression analyses assessed factors related to follow-up care. RESULTS: 1) Patients’ needs and preferences were wide-ranging with several characteristics predicting needs and preferences (ORECOG=2.69 and ORAnxiety=1.13). Needs and preferences declined as patients transitioned into their second year of follow-up (p<0.05). 2) Wide variation in practices was found, with marked differences compared to existing consensus guidelines. Multiple factors were associated with follow-up practices (RRTumor site=0.73 and RRLHIN=1.47). CONCLUSIONS: Patient characteristics can be used to personalize care and guidelines are not informing practice. Future research should evaluate individualized approaches to follow-up care.