5 resultados para Heating treatments

em Digital Commons at Florida International University


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We investigated the combined effects of salinity and hydroperiod on seedlings of Rhizophora mangle and Laguncularia racemosa grown under experimental conditions of monoculture and mixed culture by using a simulated tidal system. The objective was to test hypotheses relative to species interactions to either tidal or permanent flooding at salinities of 10 or 40 g/l. Four-month-old seedlings were experimentally manipulated under these environmental conditions in two types of species interactions: (1) seedlings of the same species were grown separately in containers from September 2000 to August 2001 to evaluate intraspecific response and (2) seedlings of each species were mixed in containers to evaluate interspecific, competitive responses from August 2002 to April 2003. Overall, L. racemosa was strongly sensitive to treatment combinations while R. mangle showed little effect. Most plant responses of L. racemosa were affected by both salinity and hydroperiod, with hydroperiod inducing more effects than salinity. Compared to R. mangle, L. racemosa in all treatment combinations had higher relative growth rate, leaf area ratio, specific leaf area, stem elongation, total length of branches, net primary production, and stem height. Rhizophora mangle had higher biomass allocation to roots. Species growth differentiation was more pronounced at low salinity, with few species differences at high salinity under permanent flooding. These results suggest that under low to mild stress by hydroperiod and salinity, L. racemosa exhibits responses that favor its competitive dominance over R. mangle. This advantage, however, is strongly reduced as stress from salinity and hydroperiod increase.

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A novel biocompatible and biodegradable polymer, termed poly(Glycerol malate co-dodecanedioate) (PGMD), was prepared by thermal condensation method and used for fabrication of nanoparticles (NPs). PGMD NPs were prepared using the single oil emulsion technique and loaded with an imaging/hyperthermia agent (IR820) and a chemotherapeutic agent (doxorubicin, DOX). The size of the void PGMD NPs, IR820-PGMD NPs and DOX-IR820-PGMD NPs were approximately 90 nm, 110 nm, and 125 nm respectively. An acidic environment (pH=5.0) induced higher DOX and IR820 release compared to pH=7.4. DOX release was also enhanced by exposure to laser, which increased the temperature to 42°C. Cytotoxicity of DOX-IR820-PGMD NPs was comparable in MES-SA but was higher in Dx5 cells compared to free DOX plus IR820 (p<0.05). The combination of hyperthermia (HT) and chemotherapy improved cytotoxicity in both cell lines. We also explored the cellular response after rapid, short-term and low thermal dose (laser/Dye/NP) induced-heating, and compared it to slow, long-term and high thermal dose cell incubator heating by investigating the reactive oxygen species (ROS) level, hypoxia-inducible factor-1&agr; (HIF-1&agr;) and vascular endothelial growth factor (VEGF) expression. The cytotoxicity of IR820-PGMD NPs after laser/Dye/NP HT resulted in higher cancer cell killing compared to incubator HT. ROS level, HIF-1&agr; and VEGF expression were elevated under incubator HT, while maintained at the baseline level under the laser/Dye/NP HT. In vivo mouse studies showed that NP formulation significantly improved the plasma half-life of IR820 after tail vein injection. Significant lower IR820 content was observed in kidney in DOX-IR820-PGMD NP treatment as compared to free IR820 treatment in our biodistribution studies (p<0.05). In conclusion, both IR820-PGMD NPs and DOX-IR820-PGMD NPs were successfully developed and used for both imaging and therapeutic purposes. Rapid and short-term laser/Dye/NP HT, with a low thermal dose, did not up-regulate HIF-1&agr; and VEGF expression, whereas slow and long-term incubator HT, with a high thermal dose, can enhance expression of both HIF-1&agr; and VEGF.^

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Anxiety disorders; such as separation anxiety disorder, generalized anxiety disorder, social phobia and specific phobia, are widespread in children and adolescents. Cognitive behavioral therapy (CBT) has been shown to be effective in reducing excessive fears and anxieties in children and adolescents. Research has produced equivocal findings that involving parents in treatment of child anxiety enhances effects over individual CBT (ICBT). The present dissertation study examined whether parental involvement can enhance individual treatment effect if the parent conditions are streamlined by targeting specific parental variables. The first parent condition, Parent Reinforcement Skills Training (RFST), involved increasing mothers' use of positive reinforcement and decreasing use of negative reinforcement. The second parent condition, Parent Relationship Skill Training (RLST), involved increasing maternal child acceptance and decreasing maternal control (or increasing autonomy granting). Results of the present dissertation findings support the use of all three treatment conditions (ICBT, RLST, RFST) for child anxiety; that is, significant reductions in anxiety were found in each of the three treatment conditions. No significant differences were found between treatment conditions with respect to diagnostic recovery rate, clinician rating, and parent rating of child anxiety. Significant differences between conditions were found on child self rating of anxiety, with some evidence to support the superiority of RLST and RFST to ICBT. These findings support the efficacy of individual, as well as parent involved CBT, and provide mixed evidence with respect to the superiority of parent involved CBT over ICBT. The conceptual, empirical, and clinical implications of the findings are discussed. ^

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Introduction: ADHD is a chronic medical condition that affects 3-7% of school-aged children. Over the last few years, there has been increased attention with children in the preschool age range. The American Academy of Pediatrics (AAP) recommends that treatment for ADHD in the preschool age range should take the form of behavior modification first, with medication only considered after behavior modification is not effective alone in treating the symptoms (AAP, 2011). However, little research has been done to examine parent perceptions of evidence-based treatment approaches for children in the preschool age range. Objective: This study sought to examine parent perceptions of psychotropic medication use for preschool age (4-6 years) children with or at-risk of ADHD. Method: Data was collected from 176 families who presented for treatment at a clinic in southeast Florida. Parents completed questionnaires about their family background, their child’s behavior, behavioral functioning, and their perceptions of medication treatment. Results: Preliminary results indicate that 50% of parents were not open to the possibility of medication, 44.6% of parents were open to the possibility of medication, and 5.4% of parents chose against medication when a physician recommended it. Results examining the extent to which severity of child behavior problems impacts parent perceptions of medication will also be presented. Conclusion: These findings demonstrate that parents of preschool children are hesitant to consider medication as a treatment option for their young children. The findings of this study are important as more and more young children are being diagnosed with ADHD each year

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Anxiety disorders; such as separation anxiety disorder, generalized anxiety disorder, social phobia and specific phobia, are widespread in children and adolescents. Cognitive behavioral therapy (CBT) has been shown to be effective in reducing excessive fears and anxieties in children and adolescents. Research has produced equivocal findings that involving parents in treatment of child anxiety enhances effects over individual CBT (ICBT). The present dissertation study examined whether parental involvement can enhance individual treatment effect if the parent conditions are streamlined by targeting specific parental variables. The first parent condition, Parent Reinforcement Skills Training (RFST), involved increasing mothers’ use of positive reinforcement and decreasing use of negative reinforcement. The second parent condition, Parent Relationship Skill Training (RLST), involved increasing maternal child acceptance and decreasing maternal control (or increasing autonomy granting). Results of the present dissertation findings support the use of all three treatment conditions (ICBT, RLST, RFST) for child anxiety; that is, significant reductions in anxiety were found in each of the three treatment conditions. No significant differences were found between treatment conditions with respect to diagnostic recovery rate, clinician rating, and parent rating of child anxiety. Significant differences between conditions were found on child self rating of anxiety, with some evidence to support the superiority of RLST and RFST to ICBT. These findings support the efficacy of individual, as well as parent involved CBT, and provide mixed evidence with respect to the superiority of parent involved CBT over ICBT. The conceptual, empirical, and clinical implications of the findings are discussed.