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Evaluating a Day Treatment Program for Children with Serious Emotional DisordersLee, Nicole Lynn 01 January 2004 (has links)
The current study used a longitudinal design to evaluate a day treatment program for children with serious emotional disorder located in Richmond, Virginia (N = 101). Child and Adolescent Functional Assessment Scale (Hodges, 1984, 1999) results were analyzed from children who had attended the program for at least six months. Repeated Measures Analysis of Variance tests indicated that children attending YDT for nine months improved their overall functioning F(2, 217) = 26.23, p = .01 as well as their functioning at school F(3,279)= 10.822, p =.01, home F(3, 244) = 6.120, p = .01, and in the community F(3, 238) = 4.158, p =.01. In addition, children improved their thinking F(2, 232) = 5.595, p = .01, behavior toward others F(3, 279)= 24.230, p = .01 and decreased the amount of self-harm F(1, 121) = 7.546, p =.01. Children began YDT with an average total CAFAS score of score of 85.90; however, after nine months of treatment, children dropped 20.40 points to an average CAFAS score of 65.50 points. Results indicate that even the most functionally impaired children in the sample demonstrated some level of improvement. Implications for social work micro and macro practice are included.
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Vliv vojenského managementu na krajinu a vegetaci Dokeska / Influence of military activities on vegetation diversity in Doksy regionStaněk, Ondřej January 2013 (has links)
The thesis focuses on description of specific area of Doksy region, situated in northern Bohemia. This region was affected by fifty years of military management. Vegetation composition, species richness and several environmental characteristics were measured and statistically tested to determine the effect of military area on landscape and vegetation. No significant difference in species richness, but important changes in species composition were discovered. Also the environmental (soil) characteristics of the area were probably changed by the military history of landscape. There were no major changes in Beta diversity uncovered, probably because of different management leading to the same resulting changes applied in the landscape. Also four invasive plant species were found in high numbers present in the area connected with past military land-use.
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Attitude and position control of quadrotors: design, implementation and experimental evaluationMardan, Maziar 06 April 2016 (has links)
The performance of a quadrotor can be significantly disturbed in presence of wind. In this paper, a simple-to-implement attitude controller is proposed to render a robust and accurate trajectory tracking in presence of disturbance and model uncertainties. The attitude controller design is based on Quantitative Feedback Theory (QFT). A fuzzy logic controller is further employed to provide satisfactory position trajectory tracking for the quadrotor. The performances of the controllers, in terms of disturbance rejection and trajectory tracking are experimentally studied. Finally, a flight scenario is performed to compare the performances of the designed QFT-Fuzzy control scheme with the ArduCopter controller. / May 2016
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Body disfigurement and self-concept: an existential-phenomenological study of men and women with psoriasis14 November 2008 (has links)
D.Litt. et Phil. / This study explored the impact of psoriasis on the self-concept (a multifaceted, hierarchical construct of self with both cognitive and emotional components) (Hattie & Marsh, 1996), of men and women who live with this cutaneous disease. Psoriasis is a common (frequently occurring), chronic inflammatory dermatological disease that can severely affect the sufferer's quality of life. While the underlying cause is unknown, the immediate cause of psoriasis is the rate of growth and differentiation of the outer layer of the skin. In a process known as hyper-proliferation (renewal of skin every four days as opposed to every 28 days), psoriasis is anatomically disfiguring. Symptoms include: the thickening of psoriatic plaques, the sloughing of silvery scales, severe itching of the affected areas and a thickening and yellowing of the fingernails. The severity of psoriasis varies from small scattered patches to total skin coverage (Young, 2005). Chronic skin diseases, such as psoriasis, can affect one's self-concept at the level of the physical, emotional, social and spiritual dimensions of self (Kew, Nevin & Cruickshank, 2002). According to Gupta and Gupta (1995), sufferers of psoriasis experience external shame (fear of negative evaluations and stigmatisation) as well as internal body shame (negative self-evaluations and self-focussed feelings). According to Stake, Huff and Zand (1995), a disturbance in one dimension of self (e.g. the physical self-concept), invariably effects other self-dimensions (e.g. the private, social self-dimensions). A study by Gupta and Gupta (1995) revealed that psoriasis was a major contributing factor to the onset of psychopathology such as depression, anxiety, unfocussed anger and obsessional behaviours. A study by Choi and Koo (as cited in Young, 2005), found that the impact of psoriasis on the psychological and emotional dimensions of self-concept to be comparable to that experienced by sufferers of more chronic diseases such as cancer, heart disease and clinical depression. General healthcare providers who treat the medical components of psoriasis may be surprised to learn that the emotional and social burdens of psoriasis are often greater than the physical toll of psoriasis on patients. Further, psoriasis is observed to be persistent, unpredictable and stressful over longer periods of time than more serious illnesses (Young, 2005). Although many people with disfiguring skin disorders cope remarkably well psychologically and socially, many do not and may require professional help in describing their bodily being in relation to the world and to come to terms with the positive and negative aspects of self (Van Deurzen-Smith, 1997). Significantly, studies in psychoneuroendocrineimmunology have shown the interconnectedness of emotions and mental attitude to physical health and which underscores the importance of treating the whole person and not just the symptoms (Linsteadt, 2002). Consistently, studies have shown the importance of self-concept to psychological health (Francis, 2002; Hattie & Marsh, 1996; Newell, 2000; Young, 2005) and body satisfaction as being pivotal in one's overall concept of self (Tiggemann & Williamson, 2000). Problematic however is that the literature indicates a dearth of dermatological studies detailing the meaning-making experiences of individuals who have undergone changes to their physical appearance as a result of this and the impact of cutaneous disease on the self-concept (Hill, 2004; Papadopoulos, Bor & Legg, 1999; Thompson & Kent, 2001). Our experiences and how we make sense of what we experience is primarily dependent upon the kinds of bodies we have and also on the ways we interact with the various environments we inhabit. It is through our embodied interactions that we inhabit a world, and it is through our bodies that we are able to understand and act within this world with varying degrees of success (Johnson, 1999). The importance of skin for an individual's psychosocial equilibrium can easily be appreciated. First, the skin represents the outward packaging of our being. Second, the cutaneous surface is what society initially perceives and with dermatological disease being the basis for social stigma. Arguably, having a healthy, unblemished skin can enhance one's self-esteem, self-identity and not infrequently, one's social standing (Koo & Yeung, 2002). Studies investigating the impact of disfiguring cutaneous disease on the self-concept appear to be lacking in the literature. In 2004, at a meeting of the Editorial Board for the Journal of Dermatology Nursing, the need for studies presenting the patient's experience of cutaneous disease was discussed. It was thought that qualitative exploration of the patient's experience of cutaneous disease would provide medical and mental healthcare professionals with valuable insights and important information to help improve dermatology patient care (Hill, 2004). Dermatology and self-concept phenomena tend to be investigated interdependently of each other. Furthermore, the majority of research in this area focuses on quantitative research design. Consequently, much of the depth of information regarding the experiential world of sufferers of cutaneous disease is invariably lost (Hill, 2004; Thompson & Kent, 2001). In light of that stated above, this study explored the meaning-making experience of men and women who suffer from psoriasis and the impact of this on the various dimensions of the self-concept. Due to the sparsity of South African studies investigating qualitatively, the experiences of persons suffering from a common, chronic dermatological condition, this study followed an existential phenomenological approach in describing the impact of psoriasis on the self-concept as told from the perspective of the men and women who live with this. Existential phenomenology seeks to explicate the essence, structure and form of both human experiences and behaviour as revealed through essentially descriptive techniques that includes disciplined reflection (Sokolowski, 2000). Given the apparent lack of awareness and knowledge of psychological processes, meaning-making and coping strategies utilised by psoriasis sufferers in their experience of this, this methodology was thought most appropriate (Hill, 2004; Newell, 2000; Papadopoulos, et al., 1999; Thompson & Kent, 2001). In terms of the areas of participation, three male and four female sufferers of psoriasis participated in the study. For all participants, psoriasis was in the active phase and covered most parts of their body. Data was collected using a questionnaire set consisting of semi-structured questions and the research question, which was open-ended. The method of data analysis was based on an integration of the works by various phenomenologists and involved six phases, namely: bracketing, intuitive grasp, eidetic reduction, textural and structural descriptions, composite textural and structural descriptions, and the final synthesis. The participants confirmed that the statements generated were accurately reflected. The results evidenced several prominent themes shared by the group, namely: (a) that the severity of the physical manifestations and the painful symptoms of psoriasis can result in negative self-concept evaluations; (b) a lack of empathy and a failure to provide knowledge on psoriasis and a priori caution of the side-effects of psoriatic medications by the medical doctors consulted was experienced by the participants as disempowering and adversely affected their emotional well-being; (c) the doctor/patient relationship was observed as pivotal in influencing the participants general concept of self; (d) the participants acceded that medical aids need to place psoriasis on the list of chronic medical conditions; (e) social stigma adversely affects self-concept evaluations; (f) public education on psoriasis is required; (g) drawing on various methods of coping was deemed crucial to the enhancement of the self-concept in the participants journey towards psychological health; (h) positive meaning-making from the psoriatic/self-concept experience enhanced quality of life issues; and finally, (i) trait self-esteem and healthy self-concept development may be important determinant factors in the psychological recovery of patients suffering from psoriasis. More specifically, in terms of self-evaluation, the participants experienced psoriasis as an assault on the physical self that was painful, embarrassing and humiliating. In redefining psoriasis in this way, the participants redefined their body image (mental construct of the body), and with the pervasiveness of negative self-evaluations an offshoot of continuous negative cognitive and emotional schemas of the body. Regarding the doctor/patient relationship, the results of the study show a need for medical doctors to expand their focus of treating the symptoms of psoriasis to incorporate a more holistic treatment approach that places emphasis on psychological, social and nutritional processes. The willingness of medical professionals to network with psychologists and other healthcare professionals and also being prepared to integrate the concept of holism into their treatment programmes was thought one method of attaining a holistic approach to the treatment and management of dermatology patients. Significantly, the doctor/patient relationship was also experienced as being an important factor in the patients drive to want to heal (healing is not here equated with cure but rather being able to approach living with psoriasis more positively). The participants in this study experienced doctors to be largely unsympathetic and not well versed in the physiology of psoriasis. Additionally, the degree of psychological trauma experienced by the participants in their suffering with psoriasis seemed to go unnoticed by the treating doctors. To this end, helplessness and feelings of disempowerment were heightened. In terms of treatment implications, the participants claimed that their treating doctors failed to inform them of the severity of the side-effects, the dangers of various treatments, and the possible inefficacy of many treatments utilised. The participants experience of this resulted in the following: a) diminished trust in the doctor/patient relationship and the medical profession generally; b) heightened body shame and repulsion of self (as opposed to feeling repulsed by the psoriasis alone); c) intense anger and with some participants describing emotional anarchy; and finally, d) in feeling left out of the treatment decision-making process, participants felt as though they had lost control over their own body. In terms of medical aid support, the participants pointed out that psoriasis is not on the government approved list of chronic conditions and as such, given their experiences, acceded that this is something that needed to be challenged. Regarding social stigma, the participants’ experience of this appeared to result in re-enforcing a sense of their feeling socially shunned and physically alienated from their familiar body. Furthermore, it would appear that social stigma might play a participatory role in increasing the severity of the psoriatic condition due to the stress evoked in the experience of feeling socially stigmatised and also the heightening of psychological difficulties experienced as participants moved from pride to shame. All participants felt public education and awareness of the onset, cause and course of psoriasis was required. Methods of coping utilised by the participants included: the seeking out of empathetic medical practitioners, psychotherapy, hypnotherapy, assertiveness skills training, implementing spirituality in their lives, and drawing upon the support of family and friends. Finally, in the midst of much adversity, the participants found an inner strength from which to reclaim their sense of self and which they attribute to having had a positive demeanour prior to suffering from psoriasis. In the deconstruction (fracturing) of self, the participants seemed to have felt compelled into a process of change that could be characterised as a reconstruction of self - an evolving of the old and new dimensions of self that would evolve further into a stronger and more resilient sense of self that characterises the participants today. The participants to this study embarked upon a journey of self-empowerment and which was a defining factor in their making meaning from their suffering. Not alluded to in the literature is that, for the participants, psoriasis became a tool that they utilised to reclaim their lives and to re-build the self anew. The results of this study reveal many important areas for future research with persons suffering from psoriasis and dermatological conditions generally, such as: i) the focussing on levels of trait self-esteem in effecting how positive change in one's self-concept may or may not occur; ii) the exploration of disfiguring skin conditions as an impetus for self-concept enhancement and creating meaning in one’s life; iii) exploring the efficacy of combining psychotherapy with medical treatments in the management of dermatology patients; iv) exploring the role of the doctor/patient relationship in the patient’s drive towards psychological health and treatment compliance; and finally, v) exploring the impact of dermatological disease on the family of the sufferer, especially given the significance of the familial system in the sufferers coping. Importantly, the results of this study suggest that having a healthy self-concept prior to the development of illness or disease is pivotal in accounting for why some people recover remarkably well psychologically and others do not. The findings of this study are valuable and will have important implications for all within the healing profession in helping to effect positive change in their future endeavours with persons who suffer from dermatological disease.
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The prevalence of body dysmorphic disorder in a South African university student sample14 January 2014 (has links)
M.A. (Psychology) / Body dysmorphic disorder is a somatoform disorder characterised by a preoccupation with an imagined defect in appearance, causing clinically significant distress or impairment in functioning. An electronic search of articles and dissertations yielded no results on the prevalence of body dysmorphic disorder in South Africa. This study aimed to determine the prevalence of body dysmorphic disorder among 395 undergraduate students at an inner-city university. Proportionate stratified random cluster sampling was used to select the sample. The students completed a demographics survey and the Body Image Disturbance Questionnaire. Results indicated an overall prevalence of 5.1%, which is similar to prevalence rates reported in existing literature among student populations. No clinically significant differences were found on the ,demographic variables of gender, race or sexual orientation. However, students differed significantly in their experience of the severity of the disorder in terms of age, such that students over the age of 21 reported higher severity levels than did students under the age of 21.
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Short and Long-term Changes in the Fish Assemblages of Bayou Lacombe, LouisianaVan Vrancken, Jeffrey M. 15 December 2007 (has links)
Over the past thirty-five years, anthropogenic disturbances around Bayou Lacombe have altered its fish assemblage. In 2005, the impact of Hurricane Katrina on southeast Louisiana presented me with a unique opportunity to explore the effects of a catastrophic storm on the Bayou. I explored the effects of natural and human disturbances on the Bayou's fish assemblage by electrofishing six historically sampled stations. My research goals were to determine: 1) which Bayou Lacombe fish assemblages were most resilient to the multiple effects of Hurricane Katrina, 2) if there were significant differences in the Bayou's fish assemblages over the past 35 years based on historical fish assemblage data, and 3) what are the drivers of fish assemblage change in Bayou Lacombe. I found significant differences in upstream fish assemblages before and after Hurricane Katrina in the Bayou. I also documented the disappearance of nearly all cyprinid species over the past 35 years.
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Gagueira e família: concepções, atitudes e sentimentos manifestados no discurso das mães / Stuttering and family: conceptions, attitudes and feelings manifested on the speech of mothersMartins, Eliana de Menezes Venancio 09 August 2002 (has links)
A gagueira é definida como um distúrbio de fluência que se caracteriza por interrupções anormais do fluxo da fala, geralmente experimentadas pelo indivíduo que gagueja como perda de controle, já que ocorrem de modo involuntário. É uma patologia de comunicação que atinge 5% da população em todo o mundo, dos quais 1% continua a gaguejar na idade adulta. Apresenta uma diversidade de sintomas que nem sempre são encontráveis em todos os indivíduos, o que dificulta diagnosticar as possíveis causas e defini-las com precisão. Medidas preventivas e, se necessário, tratamento precoce é o melhor que se pode fazer para impedir que uma criança se torne um adulto gago. A família, seio de desenvolvimento da criança, deve ser o ponto de partida para se entender o processo de aparecimento e desenvolvimento desta patologia e talvez seja dela que venham as respostas para um tratamento mais efetivo. Este trabalho tem por objetivo identificar as características significativas de comunicação às quais a criança está exposta em seu ambiente familiar, conhecer a rede de relações dentro do grupo familiar, o significado da comunicação para a família, seu padrão lingüístico, suas exigências socioculturais e suas práticas educativas. Participaram desta pesquisa quinze mães de crianças entre três e treze anos de idade, com diagnóstico de gagueira. Foram realizadas entrevistas utilizando-se roteiro semi-estruturado, cujos dados foram analisados quantitativa e qualitativamente por meio de análise temática de conteúdo. Os resultados mostram que as mães consideram a comunicação oral, o falar bem, como fundamental na vida das pessoas. Quando perceberam seus filhos gagos, ficaram preocupadas, pois julgam a gagueira um problema muito sério para o futuro deles. Corrigiam-nos, na tentativa de ajudá-los a parar de gaguejar. Todas procuraram ajuda de profissionais (fonoaudiólogos e psicólogos), quando sentiram a ineficiência de seus métodos corretivos. Pode-se constatar que algumas crianças do grupo recusaram-se a falar e tornaram-se tímidas, outras ao contrário eram falantes e extrovertidas, não se importando com a gagueira. O seu surgimento parece não depender do padrão lingüístico ou mesmo da estrutura e dinâmica familiares, não se encontrando neles um fator causal predominante para a gagueira. Conclui-se que a comunicação oral é extremamente valorizada pela sociedade e por isso a gagueira preocupa excessivamente as mães, cuja ansiedade pode interferir na manutenção deste distúrbio de comunicação. Palavras-chave: gagueira e família, distúrbio de comunicação. A gagueira é definida como um distúrbio de fluência que se caracteriza por interrupções anormais do fluxo da fala, geralmente experimentadas pelo indivíduo que gagueja como perda de controle, já que ocorrem de modo involuntário. É uma patologia de comunicação que atinge 5% da população em todo o mundo, dos quais 1% continua a gaguejar na idade adulta. Apresenta uma diversidade de sintomas que nem sempre são encontráveis em todos os indivíduos, o que dificulta diagnosticar as possíveis causas e defini-las com precisão. Medidas preventivas e, se necessário, tratamento precoce é o melhor que se pode fazer para impedir que uma criança se torne um adulto gago. A família, seio de desenvolvimento da criança, deve ser o ponto de partida para se entender o processo de aparecimento e desenvolvimento desta patologia e talvez seja dela que venham as respostas para um tratamento mais efetivo. Este trabalho tem por objetivo identificar as características significativas de comunicação às quais a criança está exposta em seu ambiente familiar, conhecer a rede de relações dentro do grupo familiar, o significado da comunicação para a família, seu padrão lingüístico, suas exigências socioculturais e suas práticas educativas. Participaram desta pesquisa quinze mães de crianças entre três e treze anos de idade, com diagnóstico de gagueira. Foram realizadas entrevistas utilizando-se roteiro semi-estruturado, cujos dados foram analisados quantitativa e qualitativamente por meio de análise temática de conteúdo. Os resultados mostram que as mães consideram a comunicação oral, o falar bem, como fundamental na vida das pessoas. Quando perceberam seus filhos gagos, ficaram preocupadas, pois julgam a gagueira um problema muito sério para o futuro deles. Corrigiam-nos, na tentativa de ajudá-los a parar de gaguejar. Todas procuraram ajuda de profissionais (fonoaudiólogos e psicólogos), quando sentiram a ineficiência de seus métodos corretivos. Pode-se constatar que algumas crianças do grupo recusaram-se a falar e tornaram-se tímidas, outras ao contrário eram falantes e extrovertidas, não se importando com a gagueira. O seu surgimento parece não depender do padrão lingüístico ou mesmo da estrutura e dinâmica familiares, não se encontrando neles um fator causal predominante para a gagueira. Conclui-se que a comunicação oral é extremamente valorizada pela sociedade e por isso a gagueira preocupa excessivamente as mães, cuja ansiedade pode interferir na manutenção deste distúrbio de comunicação. Palavras-chave: gagueira e família, distúrbio de comunicação. / Stuttering is defined as a disturb of fluency which is characterized for uncommon interruptions in the speech flow, usually experienced for the individual that stutters as a lost of control, since they occur in an involuntary way. It is a pathology of communication that affects 5% of the population in the whole world, from which 1% keeps stuttering on adult age. It displays a variety of symptoms not always possible to be found in all individuals, what makes it difficult to diagnose the possible causes and precisely define them. Preventive measures and, if necessary, precocious treatment is the best to do in order to avoid a child to become a stuttering adult. The family, heart of the childs development, must be the starting point for understanding the process of emersion and developing of this pathology and maybe it is the place where the answers for a more effective treatment come. This report has the objective of identifying the significative characteristics of communication to which a child is exposed in its family environment, understand the net of relations inside the family group, the meaning of communication to the family, its linguistic pattern, social-cultural demands and educational customs. The subjects were fifteen mothers of children amongst three and thirteen years old, with stuttering diagnosis. Interviews were made with a semi-structured script, which data were quantitative and qualitatively analyzed by means of a thematic contents analysis. The results show that mothers regard the oral communication, the well-speaking, as fundamental in peoples life. When they noticed their children stutter, they got worried, since they consider stuttering a very serious problem for their future. They corrected them, as an attempt to try to help them stop stuttering. All of them searched for professional help (phonoaudiologists and psychologists), when they felt the inefficiency of their corrective methods. It is possible to realize that some children from the group refused to speak and became timid, other children, on the contrary, talked a lot and behaved in an extroverted way, not caring about their stuttering. Its emergence seems not to depend on the linguistic pattern or even the familiar structure and dynamics, being not possible to find in them an outstanding causal factor for stuttering. It is concluded that oral communication is extremely valued by society and, this way, stuttering extremely worries mothers, whose anxiety might interfere in the persistence of this communication disturb.
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The management of insomnia on a residential pain management programme : a single case series and qualitative analysisTreves, Katharine F. January 1999 (has links)
No description available.
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Vegetation history and logging disturbance : effects on rain forest in the Lope Reserve, Gabon (with special emphasis on elephants and apes)White, Lee J. T. January 1992 (has links)
An investigation of the effects of commercial mechanised selective logging on rain forest vegetation and mammals, was undertaken in the Lope Reserve, central Gabon, between January 1989 to July 1991. Vegetation in Lope is mostly semi-evergreen lowland tropical rain forest, but there are some localised patches of savanna., which are thought to be natural in origin, but which are maintained today by regular fires started by humans. Study sites were established in areas of forest logged 20-25, 10-15, and 3-5 years previously, a fourth was logged during the study, and a fifth remained unexploited. None of the study sites had been subject to hunting in the recent past. A line-transect five kilometres in length was cut across the drainage in each site. Forest composition and structure was assessed along each transect, by identifying and measuring trees and lianes in botanical plots, counting stem density of herbaceous vegetation in the families Marantaceae and Zingiberaceae, and by measuring canopy cover at three heights. At total of 4885 trees and lianes of 327 species occurred in five 2.5 ha samples of plants greater than 10 cm dbh, whilst 1832 individuals of 137 species were found in five 25ha samples of trees greater than 70cm dbh. There were marked differences in structure and species composition both between and within sites. A model was developed to attempt to explain this variation, based upon the theory that much of Lope had been covered by savanna vegetation during a previous cool, dry climatic phase, and that forest structure and composition reflected recolonisation of the savanna by forest. Physical features such as swamps, rocky outcrops and altitude were also considered. Two types of multivariate analysis were applied to botanical data and supported the model. The effects of logging on forest vegetation were assessed by returning after logging to botanical plots established before exploitation. Damage levels were low, compared to other parts of the World, resulting in about a 10% reduction in canopy cover. Patterns of fruit production were studied by counting fallen ripe and unripe fruit on transects. Fruits encountered were classified on the basis of their morphology and dispersal mechanism. There was a period of low fruit production during the major dry season, when frugivores are likely to suffer dietary stress. A number of plant species which did produce fruit at this time were identified as species which might represent 'keystone' resources. Over 70% of fruit species were animal-dispersed, demonstrating the the important role animals play in the ecology of tropical rain forests. Forest elephant (Loxodonta africana cyclotis) diet, ecological role and group structure were analysed. The bulk of the diet consisted of the bark and leaves of trees, and some monocotyledons in the families Marantaceae and Zingiberaceae, but fruit was also important. Large-scale seasonal movements in response to fruit availability were detected. Elephants were important seed dispersers f o r many plant species, and were responsible for less than 1% of natural tree mortality. The social structure of these forest elephants differed from that of populations that have been studied i n east and southern Africa. Average group size was 2.8, and no groups of more than 10 individuals were encountered. Densi ties of primates, ungulates and squirrels were assessed using standard line-transect censuses. Resolution was poor, but statistical differences were detected between sites for some species. Chimpanzee, (Pan t. troglodytes) densities declined in logged forest, but no other species could be shown to decline after logging. Some other differences between sites were related to vegetation composition. Biomass was high, estimated a t up to 4692.6 kg km-2, but was dominated by elephants, which made up 25-82%. Conservation implications of this study are discussed, and recommendations made.
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Engelmann Spruce Survival and Regeneration After an Epidemic Spruce Beetle Outbreak on the Markagunt Plateau in Southern UtahPettit, Jessika M. 01 August 2018 (has links)
Bark beetle outbreaks are becoming more intense and severe when coupled with the effects of climate change. Engelmann spruce (Picea engelmannii) is one such species facing large-scale, epidemic spruce beetle outbreaks. Large-scale disturbances, such as beetle outbreaks, have major consequences for the future success of the ecosystem, thus highlighting the importance of understanding what promotes amplified outbreaks as well as their effects on future seedling establishment. Our research focused on two parts of a large-scale beetle outbreak: the mortality of spruce trees and the subsequent regeneration of seedlings. Our first study examined the timing of spruce mortality during an outbreak in order to identify the extent to which drought promotes host species mortality. Trees that are drought stressed have less resources to defend themselves against beetle attacks, however, the warmer temperatures associated with droughts also promote a more rapid population expansion of spruce beetles. We were specifically interested in determining the contribution that host drought stress plays during an epidemic outbreak. Our second study analyzed the patterns of regenerating seedlings with an aim to identify changes associated with the outbreak. Specifically, we were interested in how an epidemic outbreak changes the drivers of seedling establishment.
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