894 resultados para Parent-adolescent relationships
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Weed biocontrol relies on host specificity testing, usually carried out under quarantine conditions to predict the future host range of candidate control agents. The predictive power of host testing can be scrutinised directly with Aconophora compressa, previously released against the weed Lantana camara L. (lantana) because its ecology in its new range (Australia) is known and includes the unanticipated use of several host species. Glasshouse based predictions of field host use from experiments designed a posteriori can therefore be compared against known field host use. Adult survival, reproductive output and egg maturation were quantified. Adult survival did not differ statistically across the four verbenaceous hosts used in Australia. Oviposition was significantly highest on fiddlewood (Citharexylum spinosum L.), followed by lantana, on which oviposition was significantly higher than on two varieties of Duranta erecta (‘‘geisha girl’’ and ‘‘Sheena’s gold’’; all Verbenaceae). Oviposition rates across Duranta varieties were not significantly different from each other but were significantly higher than on the two non-verbenaceous hosts (Jacaranda mimosifolia D. Don: Bignoneaceae (jacaranda) and Myoporum acuminatum R. Br.: Myoporaceae (Myoporum)). Production of adult A. compressa was modelled across the hosts tested. The only major discrepancy between model output and their relative abundance across hosts in the field was that densities on lantana in the field were much lower than predicted by the model. The adults may, therefore, not locate lantana under field conditions and/or adults may find lantana but leave after laying relatively few eggs. Fiddlewood is the only primary host plant of A. compressa in Australia, whereas lantana and the others are used secondarily or incidentally. The distinction between primary, secondary and incidental hosts of a herbivore species helps to predict the intensity and regularity of host use by that herbivore. Populations of the primary host plants of a released biological control agent are most likely to be consistently impacted by the herbivore, whereas secondary and incidental host plant species are unlikely to be impacted consistently. As a consequence, potential biocontrol agents should be released only against hosts to which they have been shown to be primarily adapted.
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Rooted cutting propagation is widely used for maximising tree yield, quality and uniformity in conjunction with clonal selection. Some eucalypt species are deployed as rooted cuttings but many are considered to difficult to root. This study examined IBA effects on photoinhibition, root formation, mortality and root and shoot development in cuttings of Corymbia torelliana, C. citriodora and their hybrids. IBA had little or no effect on photoinhibition but it had strong, dose-dependent effects on root formation and mortality. IBA frequently increases primary root number of rooted cutting but it did not increase total root weight, length, surface area or volume, possibly because the highest doe (8g IBA/kg IBA/kg powder) caused leaf abscission and sometimes reduced leaf area (by 55-79%)or shoot dry weight (by 40-58%). An intermediate dose (3g IBA/kg powder) most consistnely improved root formation with little or no effect on mortality or shoot development. Across the F1 hybrid families this treatment increased the number of rooted cuttings by 72-121% and more than ddoubled the number of primary roots per rooted cutting (from 1.1-1.7 roots to 3.5-4.1 roots). This simple treatment will facilitate commercial multiplication of superior individuals or selected families of C. torelliana x C. citriodora through a vegetative propagation system.
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Spotted gum dominant forests occur from Cooktown in northern Queensland (Qld) to Orbost in Victoria (Boland et al. 2006) and these forests are commercially very important with spotted gum the most commonly harvested hardwood timber in Qld and one of the most important in New South Wales (NSW). Spotted gum has a wide range of end uses from solid wood products through to power transmission poles and generally has excellent sawing and timber qualities (Hopewell 2004). The private native forest resource in southern Qld and northern NSW is a critical component of the hardwood timber industry (Anon 2005, Timber Qld 2006) and currently half or more of the native forest timber resource harvested in northern NSW and Qld is sourced from private land. However, in many cases productivity on private lands is well below what could be achieved with appropriate silvicultural management. This project provides silvicultural management tools to assist extension staff, land owners and managers in the south east Qld and north eastern NSW regions. The intent was that this would lead to improvement of the productivity of the private estate through implementation of appropriate management. The other intention of this project was to implement a number of silvicultural experiments and demonstration sites to provide data on growth rates of managed and unmanaged forests so that landholders can make informed decisions on the future management of their forests. To assist forest managers and improve the ability to predict forest productivity in the private resource, the project has developed: • A set of spotted gum specific silvicultural guidelines for timber production on private land that cover both silvicultural treatment and harvesting. The guidelines were developed for extension officers and property owners. • A simple decision support tool, referred to as the spotted gum productivity assessment tool (SPAT), that allows an estimation of: 1. Tree growth productivity on specific sites. Estimation is based on the analysis of site and growth data collected from a large number of yield and experimental plots on Crown land across a wide range of spotted gum forest types. Growth algorithms were developed using tree growth and site data and the algorithms were used to formulate basic economic predictors. 2. Pasture development under a range of tree stockings and the expected livestock carrying capacity at nominated tree stockings for a particular area. 3. Above-ground tree biomass and carbon stored in trees. •A series of experiments in spotted gum forests on private lands across the study area to quantify growth and to provide measures of the effect of silvicultural thinning and different agro-forestry regimes. The adoption and use of these tools by farm forestry extension officers and private land holders in both field operations and in training exercises will, over time, improve the commercial management of spotted gum forests for both timber and grazing. Future measurement of the experimental sites at ages five, 10 and 15 years will provide longer term data on the effects of various stocking rates and thinning regimes and facilitate modification and improvement of these silvicultural prescriptions.
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Objective: We aimed to assess the feasibility of delivering a music therapy program on adolescent psychiatric wards. Method: We undertook a mixed-methods evaluation of a pilot program. Various active and receptive techniques were employed in group music therapy sessions delivered as part of a structured clinical program. Data collected in interviews with participants and staff and feedback questionnaires were thematically and descriptively analysed and triangulated. Results: Data from 62 questionnaires returned by 43 patients who took part in 16 music therapy sessions, and seven staff, evidenced strong support for music therapy. Patients typically reported experiencing sessions as relaxing, comforting, uplifting, and empowering; >90% would participate by choice and use music therapeutically in the future. Staff endorsed music therapy as valuable therapeutically, reporting that patients engaged enthusiastically and identified sessions as improving their own moods and ward milieu. Conclusions: Integration of music therapy in inpatient treatment of adolescents is feasible and acceptable, and is valued by staff and patients as a complement to ‘talking therapies’. Participation is enjoyed and associated with outcomes including improvement in mood, expression of feelings and social engagement consistent with recovery.
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The objectives of this study were to quantify the components of genetic variance and the genetic effects, and to examine the genetic relationship of inbred lines extracted from various shrunken2(sh2) breeding populations. Ten diverse inbred lines developed from genetic background, were crossed in half diallel. Parents and their F1 hybrids were evaluated at three environments. The parents were genotyped using 20 polymorphic simple sequence repeats (SSR). Agronomic and quality traits were analysed by a mixed linear model according to additive-dominance genetic model. Genetic effects were estimated using an adjusted unbiased prediction method. Additive variance was more important than dominance variance in the expression of traits related to ear aspects (husk ratio and percentage of ear filled) and eating quality (flavour and total soluble solids). For agronomic traits, however, dominance variance was more important than additive variance. The additive genetic correlation between flavour and tenderness was strong (r = 0.84, P <0.01). Flavour, tenderness and kernel colour additive genetic effects were not correlated with yield related traits. Genetic distance (GD), estimated from SSR profiles on the basis of Jaccard's similarity coefficient varied from 0.10 to 0.77 with an average of 0.56. Cluster analysis classified parents according to their pedigree relationships. In most studied traits, F1 performance was not associated with GD.
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Conformational energy calculations were carried out on penicillin α-and Β-sulfoxides and δ2- and δ3-cephalosporins, in order to identify the structural features governing their biological activity. Results on penicillin Β-sulfoxide indicated that in its favoured conformation, the orientation of the aminoacyl group was different from the one required for biological activity. Penicillin α sulfoxide, like penicillin sulfide, favoured two conformations of nearly equal energies, but separated by a much higher energy barrier. The reduced activity of the sulfoxides despite the nonplanarity of their lactam peptide indicated that the orientations of the aminoacyl and carboxyl groups might also govern biological activity. δ3-cephalosporins favoured two conformations of nearly equal energies, whereas δ2-cephalosporins favoured only one conformation. The lactam peptide was moderately nonplanÄr in the former, but nearly planar in the latter. The differences in the.preferred orientations of the carboxyl group between penicillins and cephalosporins were correlated with the resistance of cephalosporins to penicillinases.
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INTRODUCTION:Terrestrial top-predators are expected to regulate and stabilise food webs through their consumptive and non-consumptive effects on sympatric mesopredators and prey. The lethal control of top-predators has therefore been predicted to inhibit top-predator function, generate the release of mesopredators and indirectly harm native fauna through trophic cascade effects. Understanding the outcomes of lethal control on interactions within terrestrial predator guilds is important for zoologists, conservation biologists and wildlife managers. However, few studies have the capacity to test these predictions experimentally, and no such studies have previously been conducted on the eclectic suite of native and exotic, mammalian and reptilian taxa we simultaneously assess. We conducted a series of landscape-scale, multi-year, manipulative experiments at nine sites spanning five ecosystem types across the Australian continental rangelands to investigate the responses of mesopredators (red foxes, feral cats and goannas) to contemporary poison-baiting programs intended to control top-predators (dingoes) for livestock protection.RESULT:Short-term behavioural releases of mesopredators were not apparent, and in almost all cases, the three mesopredators we assessed were in similar or greater abundance in unbaited areas relative to baited areas, with mesopredator abundance trends typically either uncorrelated or positively correlated with top-predator abundance trends over time. The exotic mammals and native reptile we assessed responded similarly (poorly) to top-predator population manipulation. This is because poison baits were taken by multiple target and non-target predators and top-predator populations quickly recovered to pre-control levels, thus reducing the overall impact of baiting on top-predators and averting a trophic cascade.CONCLUSIONS:These results are in accord with other predator manipulation experiments conducted worldwide, and suggest that Australian populations of native prey fauna at lower trophic levels are unlikely to be negatively affected by contemporary dingo control practices through the release of mesopredators. We conclude that contemporary lethal control practices used on some top-predator populations do not produce the conditions required to generate positive responses from mesopredators. Functional relationships between sympatric terrestrial predators may not be altered by exposure to spatially and temporally sporadic application of non-selective lethal control.
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Background Adolescent Idiopathic Scoliosis is the most common type of spinal deformity, and whilst the risk of progression appears to be biomechanically mediated (larger deformities are more likely to progress), the detailed biomechanical mechanisms driving progression are not well understood. Gravitational forces in the upright position are the primary sustained loads experienced by the spine. In scoliosis they are asymmetrical, generating moments about the spinal joints which may promote asymmetrical growth and deformity progression. Using 3D imaging modalities to estimate segmental torso masses allows the gravitational loading on the scoliotic spine to be determined. The resulting distribution of joint moments aids understanding of the mechanics of scoliosis progression. Methods Existing low-dose CT scans were used to estimate torso segment masses and joint moments for 20 female scoliosis patients. Intervertebral joint moments at each vertebral level were found by summing the moments of each of the torso segment masses above the required joint. Results The patients’ mean age was 15.3 years (SD 2.3; range 11.9 – 22.3 years); mean thoracic major Cobb angle 52° (SD 5.9°; range 42°-63°) and mean weight 57.5 kg (SD 11.5 kg; range 41 – 84.7 kg). Joint moments of up to 7 Nm were estimated at the apical level. No significant correlation was found between the patients’ major Cobb angles and apical joint moments. Conclusions Patients with larger Cobb angles do not necessarily have higher joint moments, and curve shape is an important determinant of joint moment distribution. These findings may help to explain the variations in progression between individual patients. This study suggests that substantial corrective forces are required of either internal instrumentation or orthoses to effectively counter the gravity-induced moments acting to deform the spinal joints of idiopathic scoliosis patients.
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Research in organizational psychology has increasingly focused on understanding the determinants of "green" employee behavior. The present study used a daily diary design to investigate relationships between employees' daily affect, pro-environmental attitude, as well as daily task-related pro-environmental behavior (i.e., the extent to which employees complete required work tasks in environmentally friendly ways), and daily proactive pro-environmental behavior (i.e., the extent to which employees show personal initiative when acting in environmentally friendly ways at work). Fifty-six employees working in small businesses completed a baseline survey and two daily surveys over ten workdays. Daily unactivated positive affect and pro-environmental attitude positively predicted daily task-related pro-environmental behavior. In addition, daily activated positive affect positively predicted daily proactive pro-environmental behavior among employees with a less positive pro-environmental attitude but not among employees with a more positive pro-environmental attitude. These findings suggest that fostering pro-environmental attitudes and, to some extent, positive affect among employees could help organizations to promote pro-environmental behavior in the workplace.
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In this study, the authors investigated leader generativity as a moderator of the relationships between leader age, leader-member exchange, and three criteria of leadership success (follower perceptions of leader effectiveness, follower satisfaction with leader, and follower extra effort). Data came from 128 university professors paired with one research assistant each. Results showed positive relationships between leader age and leader generativity, and negative relationships between leader age and follower perceptions of leader effectiveness and follower extra effort. Consistent with expectations based on leadership categorization theory, leader generativity moderated the relationships between leader age and all three criteria of leadership success, such that leaders high in generativity were better able to maintain high levels of leadership success at higher ages than leaders low in generativity. Finally, results of mediated moderation analyses showed that leader-member exchange quality mediated these moderating effects. The findings suggest that, in combination, leader age and the age-related construct of generativity importantly influence leadership processes and outcomes. © 2011 American Psychological Association.
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Focus on opportunities is a cognitive-motivational facet of occupational future time perspective that describes how many new goals, options, and possibilities individuals expect to have in their personal work-related futures. This study examined focus on opportunities as a mediator of the relationships between age and work performance and between job complexity and work performance. In addition, it was expected that job complexity buffers the negative relationship between age and focus on opportunities and weakens the negative indirect effect of age on work performance. Results of mediation, moderation, and moderated mediation analyses with data collected from 168 employees in 41 organizations (mean age = 40.22 years, SD = 10.43, range = 19-64 years) as well as 168 peers providing work performance ratings supported the assumptions. The findings suggest that future studies on the role of age for work design and performance should take employees' focus on opportunities into account.