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Subsequent Effects (subsequent + effects)
Selected AbstractsImplications of Climatic Warming for Conservation of Native Trees and Shrubs in FloridaCONSERVATION BIOLOGY, Issue 4 2001David W. Crumpacker Climatic-envelope models are useful for simultaneous investigation of many plant species whose range-limiting mechanisms are poorly known. They are most effectively applied in regions with strong temperature and moisture gradients and low relief. Their required databases are often relatively easy to obtain. We provide an example involving the effect of six annual warming scenarios, ranging from +1° C to +2° C and from +10% to ,20% annual precipitation (some have greater warming in winter than in summer), on 117 native woody species in Florida (U.S.A.). Tree species at their southern range boundaries in several parts of Florida are likely to be negatively affected by as little as 1° C warming if it is greater in winter than in summer or is accompanied by a 20% decrease in annual precipitation. Potential species responses to an identical type of 1° C warming may be different for some conservation areas in the same region of Florida. Potentially extensive disruption of some major woody ecosystems is predicted under certain types of 1° C annual warming and under all types of 2° C annual warming that were investigated. Additional consideration of nonclimatic factors suggests that many potential effects on species and ecosystems are not underestimates of actual effects over a 100-year period of warming. We recommend monitoring for decreased fertility and viability of ecologically important, temperate woody species near their southern range limits in Florida. Early detection of such changes in fitness might then provide time for mitigations designed to alleviate more serious subsequent effects on biodiversity. Control of invasive, non-native plant species and prevention of their additional introduction, human-assisted translocation of native subtropical plant species into previously temperate parts of Florida, and restoration of more natural hydrological regimes are examples of potentially useful mitigations if climatic warming continues. Resumen: Los modelos de procesos ecológicos y los modelos empíricos han sido usados para relacionar predicciones de cambio climático con los efectos en especies de plantas y vegetación. Los modelos climáticos son útiles para la investigación simultánea de muchas especies de plantas cuyos mecanismos limitantes de rango son poco conocidos. Estos modelos son más eficientemente aplicados en regiones con gradientes de temperatura y humedad fuertes y con relieve bajo. Las bases de datos requeridas son a menudo relativamente fáciles de adquirir. Proveemos un ejemplo que involucra el efecto de seis escenarios anuales de calentamiento con un rango de +1° C a +2° C y de +10% a ,20% de precipitación anual (algunos con rangos de calentamiento mayores en el invierno que en el verano), en 117 especies leñosas nativas de Florida ( E.U.A.). Las especies de árboles en sus límites de rango al sur en diversas partes de Florida son más factibles de ser negativamente afectadas por tan poco como 1° C de calentamiento, si este es mayor en el invierno que en el verano o si es acompañado por una disminución de un 20% de precipitación anual. Las respuestas potenciales de las especies a un tipo idéntico de calentamiento de 1° C puede ser diferente para algunas áreas de conservación en la misma región de Florida. Se predicen perturbaciones potencialmente extensivas en algunos ecosistemas leñosos principales investigados bajo ciertos tipos de calentamiento anual de 1° C y bajo todos los tipos de calentamiento anual de 2° C. Las consideraciones adicionales de factores no climáticos sugieren que muchos efectos potenciales sobre las especies y ecosistemas no son subestimaciones de los efectos actuales sobre un período de calentamiento de 100 años. Se recomienda el monitoreo de la disminución de la fertilidad y viabilidad de especies leñosas templadas ecológicamente importantes cerca de los límites sureños de sus rangos en la Florida. La detección temprana de estos cambios en adaptabilidad pueden proveer tiempo para mitigaciones diseñadas para aliviar efectos posteriores más serios en la biodiversidad. Algunos ejemplos de mitigaciones potencialmente útiles en caso de que el calentamiento global continúe incluyen el control de especies de plantas invasoras no nativas y la prevención de su introducción adicional, la translocación asistida por humanos de plantas nativas subtropicales en partes previamente templadas de Florida y la restauración de regimenes hidrológicos más naturales. [source] Developmental toxicity of in ovo exposure to polychlorinated biphenyls: I. Immediate and subsequent effects on first-generation nestling American kestrels (Falco sparverius)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2003Kim Fernie Abstract We determined that in ovo exposure to polychlorinated biphenyls (PCBs) alters growth off first-generation nestlings during and one year after parental exposure. Captive American kestrels (Falco sparverius) laid eggs with environmentally relevant total PCB levels (34.1 ,g/g whole-egg wet wt) when fed PCB-spiked (Aroclor® 1248, 1254, and 1260) food (7 mg/kg body wt/d) for 100 d in 1998. In 1999, the same adults laid eggs with estimated total PCBs of 29.0 ,g/g. Nonsurviving PCB-exposed chicks were small (mass, bones) in 1998. Survivors showed a strong sex-specific growth response (mass, bones) compared to respective sex controls: Only female hatchlings were larger, and only male nestlings had longer feathers (1998); maximal growth and bone growth rates also differed (males were advanced, faster; females delayed, slower) (1999); and male nestlings fledged earlier and were smaller, while females were larger (1998, 1999). However, regardless of sex, PCB-exposed nestlings generally grew at faster rates in both years. In 1998, greater contaminant burdens and toxic equivalent concentrations in sibling eggs were associated with nestlings being lighter, having longer bones and feathers, and growing at faster rates (mass, bone) for females but slower rates (mass) for males. Both physiological-biochemical and behavioral changes are likely mechanisms. This study supports and expands on the Great Lakes embryo mortality, edema, and deformities syndrome: While PCB exposure alters nestling size, maximal growth and growth rates also change immediately, are sustained, and are sex specific. [source] Anorexia nervosa: Towards an integrative neuroscience modelEUROPEAN EATING DISORDERS REVIEW, Issue 3 2010A. Hatch Abstract We reviewed the evidence for emotion-related disturbances in anorexia nervosa (AN) from behavioural, cognitive, biological and genetic domains of study. These domains were brought together within the framework of an integrative neuroscience model that emphasizes the role of emotion and feeling and their regulation, in brain organization. PsychInfo and Medline searches were performed to identify published peer-reviewed papers on AN within each domain. This review revealed evidence for ,Emotion', ,Thinking and Feeling' and ,Self-regulation' disturbances in AN that span non-conscious to conscious processes. An integrative neuroscience framework was then applied to develop a model of AN, from which hypotheses for empirical investigation are generated. We propose that AN reflects a core disturbance in emotion at the earliest time stage of information processing with subsequent effects on the later stages of thinking, feeling and self-regulation. Copyright © 2010 John Wiley & Sons, Ltd and Eating Disorders Association. [source] CNS-irrelevant T-cells enter the brain, cause blood,brain barrier disruption but no glial pathologyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2007Alina Smorodchenko Abstract Invasion of autoreactive T-cells and alterations of the blood,brain barrier (BBB) represent early pathological manifestations of multiple sclerosis and its animal model experimental autoimmune encephalomyelitis (EAE). Non-CNS-specific T-cells are also capable of entering the CNS. However, studies investigating the spatial pattern of BBB alterations as well as the exact localization and neuropathological consequences of transferred non-CNS-specific cells have been thus far lacking. Here, we used magnetic resonance imaging and multiphoton microscopy, as well as histochemical and high-precision unbiased stereological analyses to compare T-cell transmigration, localization, persistence, relation to BBB disruption and subsequent effects on CNS tissue in a model of T-cell transfer of ovalbumin (OVA)- and proteolipid protein (PLP)-specific T-cells. BBB alterations were present in both EAE-mice and mice transferred with OVA-specific T-cells. In the latter case, BBB alterations were less pronounced, but the pattern of initial cell migration into the CNS was similar for both PLP- and OVA-specific cells [mean (SEM), 95 × 103 (7.6 × 103) and 88 × 103 (18 × 103), respectively]. Increased microglial cell density, astrogliosis and demyelination were, however, observed exclusively in the brain of EAE-mice. While mice transferred with non-neural-specific cells showed similar levels of rhodamine-dextran extravasation in susceptible brain regions, EAE-mice presented huge BBB disruption in brainstem and moderate leakage in cerebellum. This suggests that antigen specificity and not the absolute number of infiltrating cells determine the magnitude of BBB disruption and glial pathology. [source] 5,-Reductase type 2 gene variant associations with prostate cancer risk, circulating hormone levels and androgenetic alopeciaINTERNATIONAL JOURNAL OF CANCER, Issue 4 2007Vanessa M. Hayes Abstract Controversy exists over the significance of associations between the SRD5A2 (5,-reductase type 2) polymorphisms, A49T and V89L, and risk of prostate cancer. These potentially functional polymorphisms may alter life-long exposure to androgens with subsequent effects on male health and aging. The aim of this study was to examine the association of these variants with prostate cancer risk, plasma hormone levels and androgenetic alopecia. Subjects include 827 cases and 736 controls from an Australian population-based case,control study of prostate cancer. Information on prostate cancer risk factors and patterns of balding were collected. Plasma levels of testosterone, 3,-diol glucuronide (3,-diolG), dehydroepiandrosterone sulfate, androstenedione, sex hormone-binding globulin and estradiol were measured for controls. No associations with the V89L polymorphism were found. Carriers of the rarer A49T A allele were at a 60% higher risk of prostate cancer (OR = 1.60; 95% CI 1.09,2.36; p = 0.02) and 50% lower risk of vertex and frontal balding (p = 0.03) compared with men homozygous for the more common G allele. Although we found little evidence of association between this variant and plasma levels of 5 measured androgens, circulating 3,-diolG levels were 34% lower in A49T A allele carriers (p < 0.0001). Our study provides evidence that the SRD5A2 A49T A variant is associated with an increased risk of prostate cancer, lower levels of circulating 3,-diolG and decreased risk of baldness. These findings raise important questions with respect to previous assumptions concerning hormonal influences on prostate cancer risk in ageing males. © 2006 Wiley-Liss, Inc. [source] Effects of sunlight exposure and log size on pine engraver (Coleoptera: Curculionidae) reproduction in ponderosa pine slash in Northern Arizona, U.S.A.AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2009Christopher J. Hayes Abstract 1,Abiotic conditions within logs can affect pine engraver Ips pini (Say) reproductive success, and slash management techniques have been developed that exploit these relationships to reduce brood production. In the present study, we investigated the affect of sunlight exposure on phloem temperature and moisture in logs of two diameters and the subsequent effects on pine engraver reproduction. 2,Logs, 30 cm in length, with diameters of 10 and 15 cm, were cut, left in the field for natural colonization by I pini, and then placed in an open meadow and under shade cloth, providing 27% and 66% shade, until offspring beetles had left the logs. Phloem temperature and moisture were recorded over the duration of the experiment and, at the end of the field experiment, logs were dissected and galleries were measured to gauge beetle reproductive success. 3,As sunlight exposure increased, phloem temperatures increased and potentially lethal temperatures were often reached in the high-sunlight exposure but seldom in the low-sunlight. Smaller diameter logs had drier phloem than larger diameter logs. All logs dried with time but sunlight level did not affect desiccation rates. Ips pini preferred attacking larger logs and the bottom side of logs. Sunlight exposure had a significant effect on net reproductive success in smaller diameter logs, with very little net reproductive success in high-sunlight exposed logs, and the highest reproductive success was found in small diameter logs in the low-sunlight treatments. 4,Management implications of these results are discussed. [source] Agroindustrialization, globalization, and international development: An overview of issues, patterns, and determinantsAGRICULTURAL ECONOMICS, Issue 3 2000Thomas Reardon Abstract This paper offers an overview for a special issue on agroindustrialization, globalization, and international development. It sets out a conceptual framework for understanding the links among these three broad phenomena and then discusses emerging issues and evidence concerning the factors conditioning agroindustrialization in developing countries and the subsequent effects on employment, poverty, and the natural environment. We conclude with a research agenda. [source] The Effect of Betamethasone Treatment on Neuroactive Steroid Synthesis in a Foetal Guinea Pig Model of Growth RestrictionJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2010A. A. McKendry There are ongoing concerns that antenatal corticosteroids, which are administered to women at high risk of delivering preterm to reduce the incidence of respiratory distress syndrome, have adverse effects on foetal brain development and subsequent effects on behaviour and learning, when administered as repeated courses. The present study aimed to examine whether repeated betamethasone treatment alters the expression of the key-rate limiting enzyme, 5,-reductase, in the synthetic pathway of the potent neuroactive steroid allopregnanolone in the brain and placenta and whether this effect is potentiated in growth restricted foetuses. To investigate this, pregnant guinea pigs carrying either control (sham surgery) or growth-restricted foetuses were treated with vehicle or betamethasone (1 mg/kg/day) for 4 days prior to sacrifice (65d). Placental insufficiency was induced by the ablation of uterine artery branches supplying each placenta at mid gestation, resulting in foetal growth restriction characterised by ,brain sparing'. Real-time reverse transcriptase polymerase chain reaction was used to determine relative 5,-reductase type 1 and 2 mRNA expression in the placenta and brain. Immunohistochemistry was used to examine the glial fibrillary acidic protein (GFAP) expression in the subcortical white matter, CA1 and dentate regions of the hippocampus. 5,-reductase type 2 mRNA expression in the brain was markedly reduced by betamethasone treatment in male foetuses compared to vehicle-treated controls but not in female foetuses. In addition, 5,-reductase type 1 expression in the brain was increased by growth restriction and/or betamethasone treatment in female foetuses but expression in males foetuses did not increase. 5,-reductase type 2 expression in the placenta was markedly reduced by betamethasone treatment compared to vehicle-treated control. Intrauterine growth restriction and betamethasone treatment reduced GFAP expression in the CA1 region of the hippocampus in the brains of male but not female foetuses. These data indicate that betamethasone treatment suppresses placental expression and has sexually dimorphic effects on expression of neuroactive steroid synthetic enzymes in the brain. These actions may lead to adverse effects on the developing brain, particularly in male foetuses, such as the observed effects on GFAP expression. [source] Median liver lobe of woodchuck as a model to study hepatic outflow obstruction: a pilot studyLIVER INTERNATIONAL, Issue 9 2008Uta Dahmen Abstract Background: Hepatic vein outflow obstruction represents an important clinical problem in living-liver transplantation. An animal model is required to study the influence of outflow obstruction on the intrahepatic regulation of liver perfusion and the subsequent effects on liver injury and recovery during liver regeneration. The size of woodchucks enables the use of standard clinical imaging procedures. Aim: This study aims at describing hepatic vascular and territorial anatomy of the woodchuck liver based on a virtual three-dimensional (3D) visualization of the hepatic vascular tree. Methods: Woodchucks (n=6) were subjected to an all-in-one computed tomography (CT) after contrasting the vascular and the biliary tree. CT-images were used for 3D-reconstruction of hepatic and portal veins and calculation of the corresponding portal and hepatic vein territories and their respective volume using hepavision (MeVisLab). A virtual resection was performed following the Cantlie-line and territories at risk were calculated. Results: The median lobe of the woodchuck liver has a similar vascular supply and drainage as the human liver with two portal (right and left median portal vein) and three hepatic veins (left, middle and right median hepatic vein). The corresponding portal and hepatic vein subterritories are of a similar relative size compared with the human liver. Virtual splitting of the median lobe of the woodchuck liver revealed areas at risk of focal outflow obstruction, as observed clinically. Conclusion: The median liver lobe of the woodchuck represents, to a small extent, the hepatic vascular anatomy of the human liver and is therefore a suitable potential model to correlate repeated imaging of impaired liver perfusion with histomorphological findings of liver damage and regeneration. [source] Ultrastructural study of the intracellular behavior of four mineral elements in the lactating mammary gland cells: Study using conventional transmission electron microscopyMICROSCOPY RESEARCH AND TECHNIQUE, Issue 12 2008Ayadi Ahlem Abstract The effects of parenteral injection of aluminum, indium, gadolinium, or terbium in rats have been previously studied in several organs such as the liver, the kidneys, etc., but never in mammary glands. In this work, we have attempted to study the subcellular localization of these elements after their intraperitoneal administration. Their subsequent effects in the lactating mammary gland cells have also been studied. Our results using conventional transmission electron microscopy have shown that the lysosomes of the mammary glandular epithelial cells are the intracellular site of accumulation of the studied elements. Our results have also show intracellular deteriorations such as an expanded ergastoplasm and altered mitochondria after intraperitoneal injection of aluminum and indium. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc. [source] Consequences of Positive and Negative Feedback: The Impact on Emotions and Extra-Role BehaviorsAPPLIED PSYCHOLOGY, Issue 2 2009Frank D. Belschak These studies examine employees' emotional reactions to performance feedback from their supervisors as well as subsequent effects on attitudes and (intentions to show) affect-driven work behaviors (counterproductive behavior, turnover, citizenship, and affective commitment). A pre-study (N= 72) illustrates that employees regularly receive performance feedback from supervisors and that this feedback elicits different positive and negative emotions. Next, a scenario experiment (Study 1) comparing the effects of positive/negative feedback given in public/private was conducted, with a student sample (N= 240) and a sample of working adults (N= 107). In both samples, feedback has an impact on emotions and subsequently on work attitudes and behavioral intentions. The results from the scenario experiment were validated in a survey study (Study 2) among employees of a for-profit research firm (N= 86) who reported on recalled emotions and work behaviors after receiving performance feedback during appraisals. Again, different types of feedback relate to different emotions. In turn, these emotions were related to subsequent work behaviors and attitudes. Together, these studies show that feedback affects recipients' emotions and that such emotional reactions mediate the relationship between feedback and counterproductive behavior, turnover intentions, citizenship, and affective commitment. Ces travaux abordent les réactions émotives des salariés suite au feedback sur leurs performances en provenance de leur supérieur, ainsi que l'impact sur les attitudes et, au niveau des intentions, sur les conduites professionnelles soumises aux affects (comportements contre-productifs, démissions, citoyenneté et implication affective). Une préenquête (N= 72) a montré que les salariés reçoivent régulièrement des informations sur leurs résultats de la part de leur supérieur et que cette situation provoque des émotions à la fois positives et négatives. Ensuite, une expérience (Etude n° 1) comparant les conséquences d'un feedback positif ou négatif exprimé en public ou en privé a été menée à bien sur un échantillon d'étudiants (N= 240) et sur un échantillon de travailleurs (N= 107). Dans les deux cas, la rétroaction avait des retombées sur les émotions et par suite sur les attitudes professionnelles et les intentions comportementales. Les conclusions de cette expérience ont été confirmées lors d'une enquête (Etude n, 2) réalisées auprès de salariés d'une société commerciale qui décrirent leurs émotions et leurs comportements professionnels à l'issue d'une rétroaction sur leur performance lors d'une évaluation. Comme prévu, les différentes sortes de feedback sont en relation avec des émotions différentes; puis ces émotions provoquent des attitudes et des conduites professionnelles spécifiques. Au total, ces travaux montrent que le feedback affecte les émotions des individus concernés et que ces réactions émotives s'insèrent dans la relation entre la rétroaction et les comportements contre-productifs, les projets de démission, la citoyenneté et l'implication affective. [source] Immediate and subsequent effects of differential reinforcement of other behavior and noncontingent matched stimulation on stereotypy,BEHAVIORAL INTERVENTIONS, Issue 3 2010Marc J. Lanovaz A three-component multiple-schedule and brief reversals were used to examine the effects of differential reinforcement of other behavior (DRO) and noncontingent matched stimulation (NMS) on the automatically reinforced mouthing of a child with autism. Both DRO and NMS decreased immediate engagement in mouthing, but NMS produced larger reductions in the behavior. Furthermore, NMS produced subsequent effects (i.e., when the treatment was withdrawn) similar to those of prior access, whereas DRO marginally increased subsequent engagement in mouthing. The results suggest that NMS was a functionally matched intervention for mouthing. Implications for the assessment and treatment of stereotypy and applications for future research are discussed. Copyright © 2010 John Wiley & Sons, Ltd. [source] | ||||||||||||||||