829 resultados para Problem children - Behavior modification


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Ceramics are widely used in industrial applications due to their advantageous thermal and mechanical stability. Corrosion of ceramics is a great problem resulting in significant costs. Coating is one method of reducing adversities of corrosion. There are several different thin film deposition processes available such as sol-gel, Physical and Chemical Vapour Deposition (PVD and CVD). One of the CVD processes, called Atomic Layer Deposition (ALD) stands out for its excellent controllability, accuracy and wide process capability. The most commonly mentioned disadvantage of this method is its slowness which is partly compensated by its capability of processing large areas at once. Several factors affect the ALD process. Such factors include temperature, the grade of precursors, pulse-purge times and flux of precursors as well as the substrate used. Wrongly chosen process factors may cause loss of self-limiting growth and thus, non-uniformities in the deposited film. Porous substrates require longer pulse times than flat surfaces. The goal of this thesis was to examine the effects of ALD films on surface properties of a porous ceramic material. The analyses applied were for permeability, bubble point pressure and isoelectric point. In addition, effects of the films on corrosion resistance of the substrate in aqueous environment were investigated. After being exposured to different corrosive media the ceramics and liquid samples collected were analysed both mechanically and chemically. Visual and contentual differences between the exposed and coated ceramics versus the untreated and uncoated ones were analysed by scanning electron microscope. Two ALD film materials, dialuminium trioxide and titanium dioxide were deposited on the ceramic substrate using different pulse times. The results of both film materials indicated that surface properties of the ceramic material can be modified to some extent by the ALD method. The effect of the titanium oxide film on the corrosion resistance of the ceramic samples was observed to be fairly small regardless of the pulse time.

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Female sexual dysfunctions, including desire, arousal, orgasm and pain problems, have been shown to be highly prevalent among women around the world. The etiology of these dysfunctions is unclear but associations with health, age, psychological problems, and relationship factors have been identified. Genetic effects explain individual variation in orgasm function to some extent but until now quantitative behavior genetic analyses have not been applied to other sexual functions. In addition, behavior genetics can be applied to exploring the cause of any observed comorbidity between the dysfunctions. Discovering more about the etiology of the dysfunctions may further improve the classification systems which are currently under intense debate. The aims of the present thesis were to evaluate the psychometric properties of a Finnish-language version of a commonly used questionnaire for measuring female sexual function, the Female Sexual Function Index (FSFI), in order to investigate prevalence, comorbidity, and classification, and to explore the balance of genetic and environmental factors in the etiology as well as the associations of a number of biopsychosocial factors with female sexual functions. Female sexual functions were studied through survey methods in a population based sample of Finnish twins and their female siblings. There were two waves of data collection. The first data collection targeted 5,000 female twins aged 33–43 years and the second 7,680 female twins aged 18–33 and their over 18–year-old female siblings (n = 3,983). There was no overlap between the data collections. The combined overall response rate for both data collections was 53% (n = 8,868), with a better response rate in the second (57%) compared to the first (45%). In order to measure female sexual function, the FSFI was used. It includes 19 items which measure female sexual function during the previous four weeks in six subdomains; desire, subjective arousal, lubrication, orgasm, sexual satisfaction, and pain. In line with earlier research in clinical populations, a six factor solution of the Finnish-language version of the FSFI received supported. The internal consistencies of the scales were good to excellent. Some questions about how to avoid overestimating the prevalence of extreme dysfunctions due to women being allocated the score of zero if they had had no sexual activity during the preceding four weeks were raised. The prevalence of female sexual dysfunctions per se ranged from 11% for lubrication dysfunction to 55% for desire dysfunction. The prevalence rates for sexual dysfunction with concomitant sexual distress, in other words, sexual disorders were notably lower ranging from 7% for lubrication disorder to 23% for desire disorder. The comorbidity between the dysfunctions was substantial most notably between arousal and lubrication dysfunction even if these two dysfunctions showed distinct patterns of associations with the other dysfunctions. Genetic influences on individual variation in the six subdomains of FSFI were modest but significant ranging from 3–11% for additive genetic effects and 5–18% for nonadditive genetic effects. The rest of the variation in sexual functions was explained by nonshared environmental influences. A correlated factor model, including additive and nonadditive genetic effects and nonshared environmental effects had the best fit. All in all, every correlation between the genetic factors was significant except between lubrication and pain. All correlations between the nonshared environment factors were significant showing that there is a substantial overlap in genetic and nonshared environmental influences between the dysfunctions. In general, psychological problems, poor satisfaction with the relationship, sexual distress, and poor partner compatibility were associated with more sexual dysfunctions. Age was confounded with relationship length but had over and above relationship length a negative effect on desire and sexual satisfaction and a positive effect on orgasm and pain functions. Alcohol consumption in general was associated with better desire, arousal, lubrication, and orgasm function. Women pregnant with their first child had fewer pain problems than nulliparous nonpregnant women. Multiparous pregnant women had more orgasm problems compared to multiparous nonpregnant women. Having children was associated with less orgasm and pain problems. The conclusions were that desire, subjective arousal, lubrication, orgasm, sexual satisfaction, and pain are separate entities that have distinct associations with a number of different biopsychosocial factors. However, there is also considerable comorbidity between the dysfunctions which are explained by overlap in additive genetic, nonadditive genetic and nonshared environmental influences. Sexual dysfunctions are highly prevalent and are not always associated with sexual distress and this relationship might be moderated by a good relationship and compatibility with partner. Regarding classification, the results supports separate diagnoses for subjective arousal and genital arousal as well as the inclusion of pain under sexual dysfunctions.

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Föräldraskap upplevs som en utmanande uppgift i dag och det påstås att föräldrar oftare än förr skulle var i behov av råd och stöd beträffande barnuppfostran. Denna uppgift kan ytterligare försvåras om det i familjen finns ett hyperaktivt okoncentrerat barn att uppfostra. Detta arbete undersökte effekterna av ett kortvarigt gruppbaserat interventionsprogram benämnt Familjeskolan POP (Preschool Overactivity Programme). Familjeskolan är avsedd för familjer med barn i lekåldern, som visar beteendesvårigheter såsom ADHD (Attention Deficit Hyperactivity Disorder), ODD (Oppositional Deficit Disorder) eller CD (Conduct Disorder). Målet för Familjeskolan är att öka föräldrarnas kunskaper och självförtroende då de har ett krävande svårhanterligt barn att uppfostra. Familjeskolan strävar också till att reducera barns icke-önskvärda beteenden genom att öka deras sociala färdigheter och koncentrationsförmåga. Familjeskolan verkställdes i Helsingfors vid ADHD- centrets lokaliteter. 45 mödrar och deras barn från huvudstadsregionen deltog i denna undersökning. Av dessa deltog 33 i Familjeskola-programmet medan de 12 övriga bildade den s.k. kontrollgruppen. Undersökningsresultaten tyder på förbättringar beträffande både moderns och faderns föräldrakunskaper efter Familjeskola-interventionen. Det är att lägga märke till att enbart mödrar deltog i interventionsprogrammet. Efter programmet klarade mödrar enligt egen utsaga vardagen bättre. Speciellt hade de blivit bättre på att hantera barnens beteendesvårigheter och hyperaktivt okoncentrerat beteende. Resultaten påvisade också att programmet var effektivast för de mödrar som före Familjeskolan upplevde sig besitta ringa föräldrakunskaper. Mödrarna rapporterade en signifikant minskning i barnens totala beteendesvårigheter. Efter interventionen ansåg mödrarna att deras barn var mindre olydiga, hyperaktiva samt att deras beteendesvårigheter var lindrigare. Enligt dagvårdspersonalen hade barnens totala beteendesvårigheter och problem med koncentration och hyperaktivitet också minskat. Motsvarande förbättringar uppnåddes inte i kontrollgruppen. Resultaten från uppföljningsintervjun, visade också att barnens beteendeförändringar var bestående både hemma och i daghemmet. Både föräldrar och dagvårdspersonalen rapporterade en signifikant minskning i barnens totala svårigheter jämfört med innan familjerna påbörjade interventionen. Föräldrarna rapporterade en marginell minskning i barnens ADHD-liknande beteende, beteendesvårigheter och i svårigheter med kamrater, dagvårdspersonalen däremot rapporterade en signifikant minskning i barnens beteendesvårigheter, hyperaktivt/okoncentrerat beteende samt i svårigheter med kamrater mellan innan familjerna påbörjade interventionen och uppföljningen ett år efter. Resultaten av denna undersökning stödjer hypotesen att kortvariga gruppbaserade interventionsprogram kan åstadkomma permanenta förbättringar i föräldrakunskaper och barns beteende. Detta gäller främst hyperaktivitet, koncentrationssvårigheter och trotsighet.

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The survival of preterm born infants has increased but the prevalence of long-term morbidities has still remained high. Preterm born children are at an increased risk for various developmental impairments including both severe neurological deficits as well as deficits in cognitive development. According to the literature the developmental outcome perspective differs between countries, centers, and eras. Definitions of preterm infant vary between studies, and the follow-up has been carried out with diverse methods making the comparison less reliable. It is essential to offer parents upto-date information about the outcome of preterm infants born in the same area. A centralized follow-up of children at risk makes it possible to monitor the consequences of changes in the treatment practices of hospitals on developmental outcome. This thesis is part of a larger regional, prospective multidisciplinary follow-up project entitled “Development and Functioning of Very Low Birth Weight Infants from Infancy to School Age” (PIeniPAinoisten RIskilasten käyttäytyminen ja toimintakyky imeväisiästä kouluikään, PIPARI). The thesis consists of four original studies that present data of very low birth weight (VLBW) infants born between 2001 and 2006, who are followed up from the neonatal period until the age of five years. The main outcome measure was cognitive development and secondary outcomes were significant neurological deficits (cerebral palsy, CP, deafness, and blindness). In Study I, the early crying and fussing behavior of preterm infants was studied using parental diaries, and the relation of crying behavior and cognitive and motor development at the age of two years was assessed. In Study II, the developmental outcome (cognitive, CP, deafness, and blindness) at the age of two years was studied in relation to demographic, antenatal, neonatal, and brain imaging data. Development was studied in relationship to a full-term born control group born in the same hospital. In Study III, the stability of cognitive development was studied in VLBW and full-term groups by comparing the outcomes at the ages of two and five years. Finally, in Study IV the precursors of reading skills (phonological processing, rapid automatized naming, and letter knowledge) were assessed for VLBW and full-term children at the age of five years. Pre-reading skills were studied in relation to demographic, antenatal, neonatal, and brain imaging data. The main findings of the thesis were that VLBW infants who fussed or cried more in the infancy were not at greater risk for problems in their cognitive development. However, crying was associated with poorer motor development. The developmental outcome of the present population was better that has been reported earlier and this improvement covered also cognitive development. However, the difference to fullterm born peers was still significant. Major brain pathology and intestinal perforation were independent significant risk factors for adverse outcome, also when several individual risk factors were controlled for. Cognitive development at the age of two years was strongly related with development at the age of five years, stressing the importance of the early assessment, and the possibility for early interventions. Finally, VLBW children had poorer pre-reading skills compared with their full-term born peers, but the IQ was an important mediator even when children with mental retardation were excluded from the analysis. The findings suggest that counseling parents about the developmental perspectives of their preterm infant should be based on data covering the same birth hospital. Neonatal brain imaging data and neonatal morbidity are important predictors for developmental outcome. The findings of the present study stress the importance of both short-term (two years) and long-term (five years) follow-ups for the individual, and for improving the quality of care.

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In order to encourage children and adolescents to defend and support their victimized peers, it is important to identify factors that either maximize or minimize the probability that students will engage in such behaviors. This thesis is composed of four studies designed to elucidate how a variety of factors work in conjunction to explain why some children defend their victimized classmates, whereas others remain passive or reinforce the bully. The conceptual framework of this thesis is drawn from several theoretical considerations, including social cognitive learning theory, the expectancy-value framework as well as the literature emphasizing the importance of empathy in motivating behaviors. Also the child-by-environment perspective and the socialecological perspective influenced this research. Accordingly, several intra- and interpersonal characteristics (e.g., social cognitions, empathy, and social status) as well as group-level factors (e.g., norms) that may either enhance or reduce the probability that students defend their victimized peers are investigated. In Studies I and II, the focus is on social cognitions, and special attention is paid to take into account the domain-specificity of cognition-behavior processes. Self-efficacy for defending is still an interest of study III, but the role of affective empathy on defending is also investigated. Also social status variables (preference and perceived popularity) are evaluated as possible moderators of links between intrapersonal factors and defending. In Study IV, the focus is expanded further by concentrating on characteristics of children’s proximal environments (i.e., classroom). Bullying norms and collective perceptions (i.e., connectedness among the students and the teachers’ ability to deal with bullying situations) are examined. Data are drawn from two research projects: the Kaarina Cohort Study (consisting of fourth and eighth graders) and the randomized controlled trial (RCT) evaluating the effects of the KiVa antibullying program (consisting of third to fifth graders). The results of the thesis suggest that defending the victims of bullying is influenced by a variety of individual level motivational characteristics, such as social cognitions and affective empathy. Also, both perceived popularity and social preference play a role in defending, and the findings support the conceptualization that behavior results from the interplay between the characteristics of an individual child and their social-relational environment. Classroom context further influences students’ defending behavior. Thus, antibullying efforts targeting peer bystanders should aim to influence intra- and interpersonal characteristics of children and adolescents as well as their social environment.

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This paper presents a study on the dynamics of the rattling problem in gearboxes under non-ideal excitation. The subject has being analyzed by a number of authors such as Karagiannis and Pfeiffer (1991), for the ideal excitation case. An interesting model of the same problem by Moon (1992) has been recently used by Souza and Caldas (1999) to detect chaotic behavior. We consider two spur gears with different diameters and gaps between the teeth. Suppose the motion of one gear to be given while the motion of the other is governed by its dynamics. In the ideal case, the driving wheel is supposed to undergo a sinusoidal motion with given constant amplitude and frequency. In this paper, we consider the motion to be a function of the system response and a limited energy source is adopted. Thus an extra degree of freedom is introduced in the problem. The equations of motion are obtained via a Lagrangian approach with some assumed characteristic torque curves. Next, extensive numerical integration is used to detect some interesting geometrical aspects of regular and irregular motions of the system response.

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In this thesis, two negatively valenced emotions are approached as reflecting children’s self-consciousness, namely guilt and shame. Despite the notable role of emotions in the psychological research, empirical research findings on the links between guilt, shame, and children’s social behavior – and particularly aggression – have been modest, inconsistent, and sometimes contradictory. This thesis contains four studies on the associations of guilt, shame, emotion regulation, and social cognitions with children’s social behavior. The longitudinal material of the thesis was collected as a survey among a relatively large amount of Finnish preadolescents. In Study I, the distinctiveness of guilt and shame in children’s social behavior were investigated. The more specific links of emotions and aggressive behavior were explored in Study II, in which emotion regulation and negative emotionality were treated as the moderators between guilt, shame, and children’s aggressive behavior. The role of emotion management was further evaluated in Study III, in which effortful control and anger were treated as the moderators between domain-specific aggressive cognitions and children’s aggressive behavior. In the light of the results from the Studies II and III, it seems that for children with poor emotion management the effects of emotions and social cognitions on aggressive behavior are straight-forward, whereas effective emotion management allows for reframing the situation. Finally, in Study IV, context effects on children’s anticipated emotions were evaluated, such that children were presented a series of hypothetical vignettes, in which the child was acting as the aggressor. Furthermore, the identity of the witnesses and victim’s reactions were systematically manipulated. Children anticipated the most shame in situations, in which all of the class was witnessing the aggressive act, whereas both guilt and shame were anticipated the most in the situations, in which the victim was reacting with sadness. Girls and low-aggressive children were more sensitive to contextual cues than boys and high-aggressive children. Overall, the results of this thesis suggest that the influences of guilt, shame, and social cognition on preadolescents’ aggressive behavior depend significantly on the nature of individual emotion regulation, as well as situational contexts. Both theoretical and practical implications of this study highlight a need to acknowledge effective emotion management as enabling the justification of one’s own immoral behavior.

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Norms for a battery of instruments, including Denckla's and Garfield's tests of Motor Persistence, Benton's Right-Left Discrimination, two recall modalities (Immediate and Delayed) of the Bender Test, Wechsler's Digit Span, the Color Span Test and the Human Figure Drawing Test, were developed for the neuropsychological assessment of children in the greater Rio de Janeiro area. Additionally, the behavior of each child was assessed with the Composite Teacher Rating Scale (Brito GNO and Pinto RCA (1991) Journal of Clinical and Experimental Neuropsychology, 13: 417-418). A total of 398 children (199 boys and 199 girls balanced for age) with a mean age of 9.3 years (SD = 2.8), who were attending a public school in Niterói, were the subjects of this study. Gender and age had significant effects on performance which depended on the instrument. Nonachievers performed worse than achievers in most neuropsychological tests. Comparison of our data to the available counterparts in the United States revealed that American children outperformed Brazilian children on the Right-Left Discrimination, Forward Digit Span, Color Span and Human Figure Drawing Tests. Further analysis showed that the neurobehavioral data consist of different factorial dimensions, including Human Body Representation, Motor Persistence of the Legs, Orbito-Orobuccal Motor Persistence, Attention-Memory, Visuospatial Memory, Neuropsychomotor Speed, Hyperactivity-Inattention, and Anxiety-Negative Socialization. We conclude that gender and age should be taken into account when using the normative data for most of the instruments studied in the present report. Furthermore, we stress the need for major changes in the Brazilian public school system in order to foster the development of secondary cognitive abilities in our children

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The Kraft pulping process is the dominant chemical pulping process in the world. Roughly 195 million metric tons of black liquor are produced annually as a by-product from the Kraft pulping process. Black liquor consists of spent cooking chemicals and dissolved organics from the wood and can contain up to 0.15 wt% nitrogen on dry solids basis. The cooking chemicals from black liquor are recovered in a chemical recovery cycle. Water is evaporated in the first stage of the chemical recovery cycle, so the black liquor has a dry solids content of 65-85% prior to combustion. During combustion of black liquor, a portion of the black liquor nitrogen is volatilized, finally forming N2 or NO. The rest of the nitrogen remains in the char as char nitrogen. During char conversion, fixed carbon is burned off leaving the pulping chemicals as smelt, and the char nitrogen forms mostly smelt nitrogen (cyanate, OCN-). Smelt exits the recovery boiler and is dissolved in water. The cyanate from smelt decomposes in the presence of water, forming NH3, which causes nitrogen emissions from the rest of the chemical recovery cycle. This thesis had two focuses: firstly, to determine how the nitrogen chemistry in the recovery boiler is affected by modification of black liquor; and secondly, to find out what causes cyanate formation during thermal conversion, and which parameters affect cyanate formation and decomposition during thermal conversion of black liquor. The fate of added biosludge nitrogen in chemical recovery was determined in Paper I. The added biosludge increased the nitrogen content of black liquor. At the pulp mill, the added biosludge did not increase the NO formation in the recovery boiler, but instead increased the amount of cyanate in green liquor. The increased cyanate caused more NH3 formation, which increased the NCG boiler’s NO emissions. Laboratory-scale experiments showed an increase in both NO and cyanate formation after biosludge addition. Black liquor can be modified, for example by addition of a solid biomass to increase the energy density of black liquor, or by separation of lignin from black liquor by precipitation. The precipitated lignin can be utilized in the production of green chemicals or as a fuel. In Papers II and III, laboratory-scale experiments were conducted to determine the impact of black liquor modification on NO and cyanate formation. Removal of lignin from black liquor reduced the nitrogen content of the black liquor. In most cases NO and cyanate formation decreased with increasing lignin removal; the exception was NO formation from lignin lean soda liquors. The addition of biomass to black liquor resulted in a higher nitrogen content fuel mixture, due to the higher nitrogen content of biomass compared to black liquor. More NO and cyanate were formed from the fuel mixtures than from pure black liquor. The increased amount of formed cyanate led to the hypothesis that black liquor is catalytically active and converts a portion of the nitrogen in the mixed fuel to cyanate. The mechanism behind cyanate formation during thermal conversion of black liquor was not clear before this thesis. Paper IV studies the cyanate formation of alkali metal loaded fuels during gasification in a CO2 atmosphere. The salts K2CO3, Na2CO3, and K2SO4 all promoted char nitrogen to cyanate conversion during gasification, while KCl and CaCO3 did not. It is now assumed that cyanate is formed when alkali metal carbonate or an active intermediate of alkali metal carbonate (e.g. -CO2K) reacts with the char nitrogen forming cyanate. By testing different fuels (bark, peat, and coal), each of which had a different form of organic nitrogen, it was concluded that the form of organic nitrogen in char also has an impact on cyanate formation. Cyanate can be formed during pyrolysis of black liquor, but at temperatures 900°C or above, the formed cyanate will decompose. Cyanate formation in gasifying conditions with different levels of CO2 in the atmosphere was also studied. Most of the char nitrogen was converted to cyanate during gasification at 800-900°C in 13-50% CO2 in N2, and only 5% of the initial fuel nitrogen was converted to NO during char conversion. The formed smelt cyanate was stable at 800°C 13% CO2, while it decomposed at 900°C 13% CO2. The cyanate decomposition was faster at higher temperatures and in oxygen-containing atmospheres than in an inert atmosphere. The presence of CO2 in oxygencontaining atmospheres slowed down the decomposition of cyanate. This work will provide new information on how modification of black liquor affects the nitrogen chemistry during thermal conversion of black liquor and what causes cyanate formation during thermal conversion of black liquor. The formation and decomposition of cyanate was studied in order to provide new data, which would be useful in modeling of nitrogen chemistry in the recovery boiler.

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Mutations of the tumor suppressor gene p53 have been considered to be important determinants in several kinds of human cancer. Accumulation of p53 protein has been reported to correlate with more aggressive clinical behavior in some neoplasms. The role of p53 expression in adrenal cortical tumors (ACT) has not been elucidated but some studies have suggested its correlation with malignant behavior. Our objective was to determine if there is a correlation between the expression of immunoreactive p53 and the biological behavior of ACT. Fifty-seven ACT (21 from children and 36 from adults) were evaluated for p53 expression by immunohistochemistry in formalin-fixed paraffin-embedded tissue and analyzed in terms of outcome. The p53 parameter was utilized semiquantitatively. Tumors were classified as p53 negative when no positivity was observed, or when only few cells showed weak positivity (0/1+) and scored as p53 positive when there was a diffuse and strong nuclear positivity (2+/3+). In children, p53 positivity was associated with clinically malignant ACT and p53 negativity was associated with clinically benign ACT (P = 0.026). In adults' ACT, p53 positivity had an effect on disease-free survival (P<0.001) and also correlated with Weiss score, with a cutoff = 4 (P = 0.04). p53 expression was related to the clinical behavior of ACT in both children and adults and these findings seem to support a role for p53 in ACT progression.

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The objective of the present study was to examine gender differences in the influence of paternal alcoholism on children's social-emotional development and to determine whether paternal alcoholism is associated with a greater number of externalizing symptoms in the male offspring. From the Mannheim Study of Risk Children, an ongoing longitudinal study of a high-risk population, the developmental data of 219 children [193 (95 boys and 98 girls) of non-alcoholic fathers, non-COAs, and 26 (14 boys, 12 girls) of alcoholic fathers, COAs] were analyzed from birth to the age of 11 years. Paternal alcoholism was defined according to the ICD-10 categories of alcohol dependence and harmful use. Socio-demographic data, cognitive development, number and severity of behavior problems, and gender-related differences in the rates of externalizing and internalizing symptoms were assessed using standardized instruments (IQ tests, Child Behavior Checklist questionnaire and diagnostic interviews). The general linear model analysis revealed a significant overall effect of paternal alcoholism on the number of child psychiatric problems (F = 21.872, d.f. = 1.217, P < 0.001). Beginning at age 2, significantly higher numbers of externalizing symptoms were observed among COAs. In female COAs, a pattern similar to that of the male COAs emerged, with the predominance of delinquent and aggressive behavior. Unlike male COAs, females showed an increase of internalizing symptoms up to age 11 years. Of these, somatic complaints revealed the strongest discriminating effect in 11-year-old females. Children of alcoholic fathers are at high risk for psychopathology. Gender-related differences seem to exist and may contribute to different phenotypes during development from early childhood to adolescence.

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Poly-L-lactide (PLLA) is a widely used sustainable and biodegradable alternative to replace synthetic non-degradable plastic materials in the packaging industry. Conversely, its processing properties are not always optimal, e.g. insufficient melt strength at higher temperatures (necessary in extrusion coating processes). This thesis reports on research to improve properties of commercial PLLA grade (3051D from NatureWorks), to satisfy and extend end-use applications, such as food packaging by blending with modified PLLA. Adjustment of the processability by chain branching of commercial poly-L-lactide initiated by peroxide was evaluated. Several well-defined branched structures with four arms (sPLLA) were synthesized using pentaerythritol as a tetra-functional initiator. Finally, several block copolymers consisting of polyethylene glycol and PLLA (i.e. PEGLA) were produced to obtain a well extruded material with improved heat sealing properties. Reactive extrusion of poly-L-lactide was carried out in the presence of 0.1, 0.3 and 0.5 wt% of various peroxides [tert-butyl-peroxybenzoate (TBPB), 2,5-dimethyl-2,5-(tert-butylperoxy)-hexane (Lupersol 101; LOL1) and benzoyl peroxide (BPO)] at 190C. The peroxide-treated PLLAs showed increased complex viscosity and storage modulus at lower frequencies, indicating the formation of branched/cross linked architectures. The material property changes were dependent on the peroxide, and the used peroxide concentration. Gel fraction analysis showed that the peroxides, afforded different gel contents, and especially 0.5 wt% peroxide, produced both an extremely high molar mass, and a cross linked structure, not perhaps well suited for e.g. further use in a blending step. The thermal behavior was somewhat unexpected as the materials prepared with 0.5 wt% peroxide showed the highest ability for crystallization and cold crystallization, despite substantial cross linking. The peroxide-modified PLLA, i.e. PLLA melt extruded with 0.3 wt% of TBPB and LOL1 and 0.5 wt% BPO was added to linear PLLA in ratios of 5, 15 and 30 wt%. All blends showed increased zero shear viscosity, elastic nature (storage modulus) and shear sensitivity. All blends remained amorphous, though the ability of annealing was improved slightly. Extrusion coating on paperboard was conducted with PLLA, and peroxide-modified PLLA blends (90:10). All blends were processable, but only PLLA with 0.3 wt% of LOL1 afforded a smooth high quality surface with improved line speed. Adhesion levels between fiber and plastic, as well as heat seal performance were marginally reduced compared with pure 3051D. The water vapor transmission measurements (WVTR) of the blends containing LOL1 showed acceptable levels, only slightly lower than for comparable PLLA 3051D. A series of four-arm star-shaped poly-L-lactide (sPLLA) with different branch length was synthesized by ring opening polymerization (ROP) of L-lactide using pentaerythritol as initiator and stannous octoate as catalyst. The star-shaped polymers were further blended with its linear resin and studied for their melt flow and thermal properties. Blends containing 30 wt% of sPLLA with low molecular weight (30 wt%; Mwtotal: 2500 g mol-1 and 15000 g mol-1) showed lower zero shear viscosity and significantly increased shear thinning, while at the same time slightly increased crystallization of the blend. However, the amount of crystallization increased significantly with the higher molecular weight sPLLA, therefore the star-shaped structure may play a role as nucleating agent. PLLA-polyethylene glycol–PLLA triblock copolymers (PEGLA) with different PLLA block length were synthesized and their applicability as blends with linear PLLA (3051D NatureWorks) was investigated with the intention of improving heat-seal and adhesion properties of extrusion-coated paperboard. PLLA-PEG-PLLA was obtained by ring opening polymerization (ROP) of L-lactide using PEG (molecular weight 6000 g mol-1) as an initiator, and stannous octoate as catalyst. The structures of the PEGLAs were characterized by proton nuclear magnetic resonance spectroscopy (1H-NMR). The melt flow and thermal properties of all PEGLAs and their blends were evaluated using dynamic rheology, and differential scanning calorimeter (DSC). All blends containing 30 wt% of PEGLAs showed slightly higher zero shear viscosity, higher shear thinning and increased melt elasticity (based on tan delta). Nevertheless, no significant changes in thermal properties were distinguished. High molecular weight PEGLAs were used in extrusion coating line with 3051D without problems.

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The objective of this study is to increase understanding of the nature and role of trust in temporary virtual problem-solving teams engaged in real-life co-creation activities, while much of previous research has been conducted in student settings. The different forms and bases of trust, possible trust barriers and trust building actions, and perceived role of trust in knowledge sharing and collaboration are analyzed. The study is conducted as a qualitative case study in case company. Data includes interviews from 24 people: 13 from 3 different project teams that were going on during the study, 8 from already finalized project teams, and 3 founders of case company. Additional data consists of communication archives from three current teams. The results indicate that there were both knowledge-based and swift trust present, former being based on work-related personal experiences about leaders or other team members, and latter especially on references, disposition to trust and institution-based factors such as norms and rules, as well as leader and expert action. The findings suggest that possible barriers of trust might be related to lack of adaptation to virtual work, unclear roles and safety issues, and nature of virtual communication. Actions that could be applied to enhance trust are for example active behavior in discussions, work-related introductions communicating competence, managerial actions and face-to-face interaction. Finally, results also suggest that trust has a focal role as an enabler of action and knowledge sharing, and coordinator of effective collaboration and performance in temporary virtual problem-solving teams.

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INTODUCTION: Nephrotic syndrome is one of the most frequent glomerular diseases among children, and steroid therapy remains as the treatment choice. In spite of this, 10 to 15% of the patients are steroidresistant, and the best therapy for such cases has never been defined. Mycophenolate acid (MA) is one of the treatments used in such situations. OBJECTIVE: To describe the clinical behavior of children diagnosed with steroid-resistant nephrotic syndrome (SRNS) and to assess the therapeutic response to MA. METHODS: This was a retrospective and descriptive study. RESULTS: 26 clinical records of patients with SRNS; 70% male and 30% female. All patients underwent kidney biopsies, which showed a predominance of focal segmental glomerulosclerosis (FSGS). The immunosuppresive drugs used were: Mycophenolate mofetil (MMF) 100%, Cyclosporine 69.2%, Cyclophosphamide 23.1%, and Rituximab 23%. One month after treatment initiation with MMF 61.5% achieved remission. The median of relapses per year for the patients was 3 (p25: 2.75 - p75: 4). This median became 1 (p25: 1 - p75: 3.25) after using this medication (p = 0.08). Furthermore, prior to the start of the MMF treatment, the median of the steroid dose was 1 (p25: 0.5- p75: 1.62) mg/k/day. After using MMF, this median became 0.07 (p25: 0 - p75: 0.55) mg/k/day (p < 0.001), in 8 patients prednisolone was stopped. CONCLUSION: In our experience, treatment with MMF showed positive results such as decrease in the frequency of relapses, less proteinuria, and reduction in the dose of steroids administered without deterioration of glomerular filtration rates. However, more studies are needed to assess efficacy, safety, and optimal dosage.

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The parents of premature infants, especially the mothers, are at increased risk for distress. Infants born prematurely are at risk for developmental problems. The aim of this study was to investigate whether the psychological well-being of both parents is associated with child development in very low birth weight (VLBW, ≤1500g) children. The burden of prematurity-related morbidity to the children and to the family was also assessed. A cohort of 201 VLBW infants born during 2001–2006 in the Turku University Hospital, Finland, and their parents were studied (I–IV). One study included a control group (n=166) of full-term infants (IV). The psychological well-being of the parents was evaluated by assessments of depressive symptoms, parenting stress, the sense of coherence and general family functioning. Cognitive, behavioral, and socio-emotional development, and the health-related quality of life (HRQoL) of the children were determined when the children were 2 to 8 years old. The psychological well-being of the parents was associated with the cognitive, behavioral and social development of the VLBW children. The VLBW infants with prematurity-related morbidities had a poorer HRQoL and the general functioning of the family was inferior compared to the control children and their families. 64.5% of the VLBW children survived without morbidities. Most of the VLBW children did not have significant behavior problems (93%), had normal social skills (63%), had no emotional problems (64%), and had no problems in executive functioning (62%). Only 3% of the surviving VLBW infants had significant cognitive delay. In conclusion, the depressive symptoms and stress of the parents can be risk factors for disadvantageous child development, while a strong sense of coherence can be protective. Parents of the premature children with developmental delays might also experience more depressive symptoms and stress than other parents. Prematurity-related morbidities were a burden to the VLBW child as well as to the family.