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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Combinational Effects of Polymethoxyflavones and Atorvastatin in Inhibiting Human Breast Cancer Cells

Li, Longfang 01 January 2013 (has links) (PDF)
Utilization of potential synergistic interactions among different bioactive agents is a promising approach to inhibit complex diseases such as cancer. Nobiletin (NBT) and tangeretin (TAN) are major polymethoxyflavones (PMFs) found in citrus fruits. Herein, we studied NBT and TAN in combination with atorvastatin (ATST, Lipitor, a cholesterol-lowering drug) in MDAMB231 and MCF-7 human breast cancer cells. Both NBT/ATST and TAN/ATST combinations at low doses produced much stronger inhibitory effect on cancer cell viability in comparison to those produced by NBT, TAN, or ATST alone at much higher doses. Isobologram analysis confirmed that both NBT/ATST and TAN/ATST combinations produced strong synergy in inhibiting the growth of two breast cancer cell lines. Flow cytometry analysis showed that both NBT/ATST and TAN/ATST combinations caused significant cell cycle arrest at G0/G1 phase in MDAMB231 cells (ER+). Consistent with these results, PMFs and ATST combinations decreased expression levels of phospho Rb, cyclin D1, and CDK4. Further experiments showed that the combination treatment induced autophagy and late apoptosis in MDA-MB-231 cells. Meanwhile, co-treatment of PMFs and ATST induce G2/M phase in MCF-7 (ER+) cells.. The combination of PMFs and ATST also caused autophagy in MCF-7 cells, which was evidenced by activation of LC3B and P62. In conclusion, our result demonstrated strong synergy between two major citrus PMFs (NBT and TAN) and ATST in inhibiting human breast cancer cell growth.
202

Good Times?: Simulating the Seventies in Nineties Hollywood;

Johnson, Logan 05 May 2023 (has links)
No description available.
203

Immunological Consequences of HLA-B27 Misfolding: Implications for Spondyloarthropathy Pathogenesis

Turner, Matthew Joseph 08 October 2007 (has links)
No description available.
204

[pt] AVALIAÇÃO DAS POSSÍVEIS SINERGIAS A SEREM GERADAS EM UMA FUSÃO DA TIM S.A. COM A OI S.A / [en] EVALUATION OF POTENTIAL SYNERGIES GENERATED BY A MERGER BETWEEN TIM S.A. AND OI S.A.

CARLOS HENRIQUE DA SILVA PADUA 26 November 2019 (has links)
[pt] O mercado de telecomunicações no Brasil está alcançando a maturidade e a competição tem pressionado as margens das operadoras. Há especulações sobre um processo de racionalização e consolidação da indústria em curso para os próximos anos. Considerando a complementaridade das operações, bem como o baixo nível de concentração de mercado e de consolidação do espectro de frequências, o objetivo deste estudo foi avaliar as potenciais sinergias geradas em uma fusão entre a TIM e a Oi. A avaliação foi feita utilizando o método de fluxo de caixa descontado, perpetuidade, o CAPM e os múltiplos de mercado. Também foi levada em consideração a vivência de 10 anos em implantação de projetos estratégicos e planejamento estratégico nas duas operadoras avaliadas. O resultado obtido foi um alto potencial de sinergias, mesmo com premissas conservadoras, principalmente na geração de receita, na redução de custos de rede e investimentos sobrepostos. Ao final, foi possível inferir que o volume esperado de sinergias poderia gerar um valor maior para as companhias em uma operação consolidada do que em operações separadas. / [en] The telecommunications market in Brazil is reaching maturity and the competition has pushed the operators margins. Market agents speculate about an ongoing rationalization and consolidation process in the industry for the coming years. Considering the complementarity of the operations, a low level of market concentration and frequency spectrum consolidation, the analysis aimed to evaluate the potential synergies generated by a merger between TIM and Oi. The evaluation used the discounted cash flow method, perpetuity, CAPM and market multiples. It was also taken into account the experience of 10 years in the implementation of strategic projects and strategic planning in the two operators. As a result, a high potential for synergies was found, even using conservative assumptions, mainly in revenue generation, reduction of network costs and overlapping investments. The findings suggest that it is possible to infer, given the expected volume of synergies, a greater value for the companies in a consolidated operation than in a separate scenario.
205

Nurses' communication with mechanically ventilated patients in the intensive care units

Dithole, Kefalotse Sylvia 21 November 2014 (has links)
Critically ill patients experience overwhelming communication problems; caused by intubation and cognitive, sensory or language deficits that distance the patients from communicating their needs and wants from nurses and loved ones. The purpose of this study was to explore communication patterns and strategies with the aim of implementing intervention strategies for nurse/patient communication in the intensive care units. The American Association of Critical Care Nurses’ Synergy Model for Patient Care was used to guide the study. A mixed method approach using quasi-experimental design combining quantitative and qualitative data collections and analysis was used. Concurrent data collection for quantitative and qualitative data was used. Auditing of patient’s files, protocols, family counselling conference and in-service books and a survey for nurses was used for quantitative data. Qualitative data collection was through interviewing nurses and nurse managers. Lack of documentation and use of other communication strategies were the key findings of the study. In accordance with the model used for the study clinical judgment and moral distress were found to be common among nurses. Lack of collaboration between nurses and other health care workers was also attributed to poor communication with mechanically ventilated patients. Conclusions derived from the study are that nurses need to be supported through informal and formal training on documentation and use of communication methods available / Health Studies / D. Litt. et Phil. (Health Studies)
206

In Vitro antimicrobial synergy testing of Acinetobachter Baumannii

Martin, Siseko 12 1900 (has links)
Bibliography / Thesis (MMed (Pathology. Medical Microbiology))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Acinetobacter baumannii has emerged as one of the most troublesome nosocomial pathogens globally. This organism causes infections that are often extremely difficult to treat because of the widespread resistance to the major antibiotic groups. Colonization or infection with multidrugresistant A. baumannii is associated with the following risk factors: prolonged hospital stay, admission to an intensive care unit (ICU), mechanical ventilation, and exposure to broad spectrum antibiotics, recent surgery, invasive procedures, and severe underlying disease. A. baumannii has been isolated as part of the skin flora, mostly in moist regions such as axillae, groin and toe webs. It has also been isolated from the oral cavity and respiratory tract of healthy adults. Debilitated hospitalized patients have a high rate of colonization, especially during nosocomial Acinetobacter outbreaks. This organism is an opportunistic pathogen as it contains few virulence factors. Clinical manifestations of A. baumannii include nosocomial pneumonia, nosocomial bloodstream infections, traumatic battlefield and other wound infections, urinary tract infections, and post-neurological surgery meningitis. Fulminant community-acquired pneumonia has recently been reported, indicating that this organism can be highly pathogenic. The number of multidrug-resistant A. baumannii strains has been increasing worldwide in the past few years. Therefore the selection of empirical antibiotic treatment is very challenging. Antibiotic combinations are used mostly as empirical therapy in critically ill patients. One rationale for the use of combination therapy is to achieve synergy between agents. The checkerboard and time-kill methods are two traditional methods that have been used for synergy testing. These methods are labor intensive, cumbersome, costly, and time consuming. The E-test overlay method is a modification of the E-test method to determine synergy between the different antibiotics. This method is easy to perform, flexible and time efficient. The aim of this study was to assess the in vitro activity of different combinations of colistin, rifampicin, imipenem, and tobramycin against selected clinical strains of A. baumannii using the checkerboard and the E-test synergy methods. The MICs obtained with the E-test and broth microdilution method were compared. The results of the disk diffusion for imipenem and tobramycin as tested in the routine microbiology laboratory were presented for comparison. Overall good reproducibility was obtained with all three methods of sensitivity testing. The agreement of MICs between the broth dilution and E-test methods was good with not more than two dilution differences in MIC values for all isolates, except one in which the rifampicin E-test MIC differed with three dilutions from the MIC obtained with the microdilution method. However, the categorical agreement between the methods for rifampicin was poor. Although MICs did not differ with more than two dilutions in most cases, many major errors occurred because the MICs clustered around the breakpoints. The combinations of colistin + rifampicin, colistin + imipenem, colistin + tobramycin, rifampicin + tobramycin, and imipenem + tobramycin all showed indifferent or additive results by the E-test method. No results indicating synergy were obtained for all the above-mentioned combinations. There was one result indicating antagonistic effect for the combination of colistin + tobramycin. The results of the checkerboard method showed results indicating synergy in four of the six isolates for which the combination of colistin and rifampicin was tested. The other two isolates showed indifferent/additive results. All the other combinations showed indifferent/additive results for all isolates except isolate 30 (col + tob) and isolate 25 (rif + tob) which showed synergism. No antagonistic results were observed by the checkerboard method. When the results obtained with the E-test and checkerboard methods were compared, it was noted that for most antibiotic combinations an indifferent/additive result was obtained. However, for the colistin + rifampicin combination, the checkerboard method showed synergism for 4 of 6 isolates, whereas the E-test method showed indifference and an additive result in one. For the rifampicin + tobramycin, and colistin + tobramycin combinations, synergism was also shown with the checkerboard method in one isolate for each combination. The E-test method however showed an indifferent and additive result respectively. . The E-test method was found to be a rapid, reproducible, easy-to-perform, and flexible method to determine synergistic antibiotic activity. This study was however limited by low numbers of isolates. This might explain why no synergistic results were obtained with the E-test method and few synergistic results with the checkerboard method. Genotypic analysis using pulse-field gel electrophoresis (PFGE) may be considered in future studies to determine relatedness of the isolates which will facilitate the selection of different strains for synergy testing. Furthermore, clinical studies are needed to establish whether in vitro synergy testing is useful in the clinical setting and whether the results of synergy testing will have any bearing on the clinical outcome of patients infected with multidrug resistant A. baumannii. / AFRIKAANSE OPSOMMING: Acinetobacter baumannii het wêreldwyd as een van die mees problematiese nosokomiale patogene verskyn. Hierdie organisme veroorsaak infeksies wat dikwels baie moeilik is om te behandel weens wydverspreide weerstandigheid teen major antibiotikagroepe. Kolonisasie of infeksie met multi-weerstandige A. baumannii word geassosieer met die volgende riskofaktore: verlengde hospitaalverblyf, toelating tot ‘n intensiewe sorgeenheid (ICU), meganiese ventilasie, blootstelling aan breëspektrum antibiotika, onlangse chirurgie, indringende prosedures en ernstige onderliggende siekte. A. baumannii kan deel vorm van die normale velflora, veral in die axillae, inguinale area en tussen die tone. Dit is ook al vanuit die mondholte en die respiratoriese traktus van gesonde volwassenes geïsoleer. Verswakte gehospitaliseerde pasiënte word veral gekoloniseer gedurende nosokomiale Acinetobacter uitbrake. Hierdie organisme is ‘n opportunistiese patogeen en bevat min virulensie faktore. Kliniese manifestasies van A. baumannii sluit nosokomiale pneumonie, nosokomiale bloedstroom infeksies, troumatiese slagveld- en ander wondinfeksies, urienweginfeksies en meningitis wat volg op neurologiese chirurgie in. Fulminerende gemeenskapsverworwe pneumonie is onlangs beskryf en dui aan dat hierdie organisme hoogs patogenies kan wees. Die aantal multi-weerstandige A. baumannii stamme het wêreldwyd toegeneem oor die laaste paar jare. Daarom is die seleksie van empiriese antibiotiese behandeling ‘n uitdaging. Antibiotika kombinasies word meestal as empiriese behandeling in ernstige siek pasiënte gebruik. Die beginsel hiervan is om sinergistiese werking tussen agente te verkry. Die “checkerboard” en “time-kill” metodes is twee tradisionele metodes van sinergisme toetsing. Hierdie metodes is werksintensief, duur en tydrowend. Die E-toets sinergisme metode is gebaseer op die E-toets metode. Hierdie metode is maklik, buigbaar en tydseffektief. Die doel van hierdie studie was om die in vitro aktiwiteit tussen verskillende antibiotika kombinasies van colistin, rifampisien, imipenem, en tobramisien teen geselekteerde kliniese A. baumannii isolate te toets met die “checkerboard” en E-toets sinergisme toetsing metodes. Die minimum inhibitoriese konsentrasies (MIKs) verkry met die E-toets en “broth microdilution” metode is ook vergelyk. Die resultate van die skyfie diffusie metode (die metode wat in die roetiene mikrobiologie laboratorium gebruik word) vir imipenem en tobramisien word ook verskaf vir vergelyking van die resultate van verskillende sensitiwiteitsmetodes. In oorsig is goeie herhaalbaarheid van resultate verkry met al drie metodes van sensitiwiteitstoetsing. Die ooreenstemming van MIKs tussen die “broth dilution” en E-toets metodes was goed en resultate het met nie meer as twee verdunnings in MIK waardes verskil nie. Daar is een uitsondering waar die rifampisien E-toets MIK waarde met drie verdunnings van die MIK waarde verkry met die “microdilution” metode verskil. Die ooreenstemming tussen die sensitiwiteitskategorie resultate tussen die twee metodes was egter swak vir rifampisien. Alhoewel die MIKs in die meeste gevalle met nie meer as twee verdunnings in waarde verskil het nie, was daar baie major foute aangetoon omdat die MIKs rondom die breekpunte geval het. Die kombinasies van colistin + rifampisien, colistin + imipenem, colistin + tobramisien, rifampisien + tobramisien, en imipenem + tobramisien het oorwegend slegs matige interaksie met die E-toets metode getoon. Geen sinergisme is verkry met enige van die antibiotika kombinasies met hierdie metode nie. Daar was egter een resultaat wat antagonisme getoon het vir die kombinasie van colistin + tobramycin. Die resultate van die “checkerboard” metode het sinergisme getoon in vier van die ses isolate wat vir die kombinasie van colistin en rifampisien getoets was. Die ander twee isolate het slegs matige interaksie getoon. Al die ander kombinasies het ook slegs matige interaksie getoon, behalwe in isolaat 30 (col + tob) en isolaat 25 (rif + tob) waar die spesifieke kombinasies sinergisme getoon het. Geen antagonisme is waargeneem met die “checkerboard” metode nie. Met vergelyking van die E-toets en “checkerboard” metodes, is dit opmerklik dat vir die meeste van die antibiotika kombinasies slegs matige interaksie verkry is. Vir die colistin + rifampisien kombinasie toon die “checkerboard” metode egter sinergisme vir 4 uit 6 isolate, terwyl die E-toets metode slegs matige interaksie toon. Vir rifampisien + tobramisien, en colistin + tobramisien kombinasies is sinergisme getoon met die “checkerboard” metode in een isolaat vir elke kombinasie. Die E-toets metode het slegs matige interaksie getoon. Die E-toets sinergisme metode was vinnig, herhaalbaar en maklik om uit te voer. Hierdie studie word egter beperk deur lae getalle van isolate. Dit mag verklaar waarom geen sinergistiese resultate met die E-toets metode verkry is nie en die min sinergistiese resultate met die “checkerboard” metode. Genotipiese analiese met “pulse-field gel electrophoresis” mag in aanmerking geneem word in toekomstige studies om die verwantskap tussen isolate te bepaal wat die seleksie van verskillende stamme vir sinergisme toetsing sal vergemaklik. Verder, kliniese studies is nodig om te bepaal of in vitro sinergisme toetsing van waarde is en of die resultate van sinergisme toetsing ‘n rol speel in die kliniese uitkoms van pasënte geïnfekteer met multiweerstandige A. baumannii. / The National Health Laboratory Serivice
207

「新三中」跨媒體集團資源整合與綜效—以【超級星光大道】之節目策略為例 / A Research on Resources Integration and Synergies Exploiting for “Neo-San Chung” Media Conglomerate: A Case Study of the TV Show “One Million Star” Programming Strategy

邱琬淇, Chiu, Wan-Chi Unknown Date (has links)
本研究關注跨媒體集團執行資源整合與綜效化經營導向之間的策略關係,並且聚焦電視節目經營的運作範圍。主要經由深度訪談的研究途徑,旨在透過個案節目:【超級星光大道】之實務分析,作為檢視中視、中天與中時所形成的「新三中」跨媒體集團之對照,藉以探究新三中資源整合的策略意涵,以及產出的綜效價值與相關影響,同時思考跨媒體集團於電視節目市場的經營邏輯與整合模式。 研究結果指出,新三中在此節目的經營過程,並非經過系統性地研擬與完整規劃,而是呈現隨市場情勢,漸進調整的發展狀態。其中,節目的收視表現和集團政策的配合是影響資源整合策略執行的關鍵。另外在價值創造方面,不管是「行銷、營運與管理綜效」,【超級星光大道】為新三中分別都在各個細部層次帶來正向的效益成長。但本研究也發現新三中的資源整合,出現難以整合管理,並且對新聞專業義理產生衝擊,尤其為了追求綜效卻導致顧此失彼造成矛盾等反向效應,種種問題隱憂代表跨媒體集團的資源整合雖能實現正面綜效的價值,但不得忽略其同時亦能產生負面綜效的影響作用。 / This research concentrates on the interaction between implementing resources-integration and operating synergy-oriented strategies in media conglomerates, with focusing on television program management. Taking the TV show “One Million Star” as an empirical investigation with depth-interviewing approach, the study intends to analyze the media conglomerate “Neo-San Chung” which comprising CTV, CTiTV and China Times three media companies; the main purpose is to explore strategic meanings, synergy value and related influences behind the resources-integration in “Neo-San Chung”. Also, the research concerns about the governance logic and the model of integration in media market. According to the research, instead of systematic design and planning step by step, the managing process of the TV show by “Neo-San Chung” presents a changing condition varying with market circumstances. Meanwhile, the program’s performance and the conglomerate’s governance policy are crucial factors. Regarding the aspect of creating value, “One Million Star” produces advantages in each detailed layers of marketing, operating and managing synergies. However, the study notices that there are some derivative problems, such as difficulties in integrated management, conflicts in Journalism values, and especially the contradiction resulted from realizing synergy benefits. Although resources integration could bring media conglomerates positive synergy values, these problems reveal that negative synergy might arise simultaneously and become potential crisis.
208

Verzerrter Recall als potentielles Hindernis für Synergie bei Gruppenentscheidungen / Biased Recall as a potential obstacle for the achievement of synergy in decision-making groups

Giersiepen, Annika Nora 20 December 2016 (has links)
In Hidden Profiles gelingt es Gruppen häufig nicht, ihr Potenzial, bessere Entscheidungen als jedes ihrer Mitglieder zu treffen, zu erfüllen. Für dieses Phänomen wurden bereits verschiedene Ursachen ermittelt. Dazu gehören insbesondere Verzerrungen im Inhalt der Gruppendiskussion sowie der Bewertung von entscheidungsrelevanten Informationen durch die Gruppenmitglieder. In der vorliegenden Arbeit wird nun ein weiterer Aspekt individueller Informationsverarbeitung untersucht, dessen Verzerrung einen nachteiligen Einfluss auf die Entscheidungsqualität von Diskussionsgruppen haben könnte: der individuelle Recall bezüglich aufgabenrelevanter Informationen. Dabei werden zwei Verzerrungen postuliert: Ein Erinnerungsvorteil von Informationen, welche die ursprüngliche Präferenz des jeweiligen Gruppenmitglieds unterstützen sowie eine Verzerrung zugunsten von Informationen, die bereits vor der Diskussion verfügbar sind. Es wird angenommen, dass beide Verzerrungen einen negativen Einfluss auf die Entscheidungsqualität des Individuums und somit auch der gesamten Gruppe haben. Diese Annahmen wurden in einer Reihe von vier Experimenten und der Reanalyse zweier früherer Studien untersucht. Insgesamt wurde dabei Evidenz für einen Erinnerungsvorteil eigener, vor der Diskussion bekannter Informationen gegenüber in der Diskussion neu gelernten Informationen gefunden. Belege für einen Erinnerungsvorteil präferenzkonsistenter Informationen zeigten sich dagegen nur vereinzelt und in einer metaanalytischen Zusammenfassung nicht in signifikantem Maße. Eine experimentelle Manipulation der Erinnerungsverzerrungen liefert keinen Hinweis auf einen Zusammenhang zwischen diesen Faktoren und der Entscheidungsqualität in Hidden-Profile- Situationen. Eine Verzerrung der individuellen Erinnerung im Hinblick auf entscheidungsrelevante Informationen ist somit nach den Ergebnissen dieser Arbeit keine sinnvolle Erweiterung der bestehenden Erklärungsansätze für das Scheitern von Entscheidungsgruppen an der Realisierung von Synergien.
209

Étude per-opératoire par stimulation électrique directe des représentation sensorimotrices corticales et cérébelleuses chez l'homme / Per-operative investigation with direct electrical stimulation of cortical and cerebellar sensorimotor representations in humans

Mottolese, Carmine 21 December 2013 (has links)
Durant les dernières décennies, le système moteur a été largement étudié. Pourtant, bien des zones d'incertitudes persistent concernant d'une part la nature des circuits neuronaux de haut niveau impliqués dans l'émergence des sentiments d'intention ou de conscience motrice et d'autre part l'organisation des structures cérébrales de bas-niveau impliquées dans l'expression de ces sentiments. Il a été suggéré que le cortex pariétal et l'aire motrice supplémentaire pourraient jouer un rôle dans la génération des intentions motrices, alors que le cortex prémoteur pourrait plutôt sous-tendre la conscience du geste. Cela étant, les processus exacts implémentés dans chacune de ces régions, la façon dont elles interagissent fonctionnellement et la nature des signaux qu'elles échangent avec les structures sensorimotrices considérées de bas-niveau demeurent méconnus. Il est établi que ces structures bas-niveau, dont le cortex moteur primaire et le cervelet, contiennent des cartes sensorimotrices organisées de manière topographique. Cependant, l'organisation fine de cette topographie et la nature des interactions entre les différentes cartes restent à définir. Dans ce travail de thèse, j'ai utilisé la stimulation électrique directe chez des patients opérés de tumeurs et malformations cérébrales pour explorer la manière dont les multiples représentations motrices sont organisées et pour identifier les régions responsables de l'émergence des sentiments d'intention et de conscience motrice. J'ai alors pu montrer, en particulier, l'existence de cartes motrices multiples au sein des cortex moteur primaire et cérébelleux. Par ailleurs, j'ai pu identifier le rôle critique du cortex pariétal pour l'émergence du sentiment d'intention motrice et -sur la base de processus prédictifs- de la conscience d'agir. Par rapport à ce point, j'ai aussi pu mettre en évidence que le cortex prémoteur était impliqué, à travers un contrôle continu des prédictions pariétales, dans l'émergence d'une conscience d'agir non plus inférée mais véritable / During the last five decades, the motor system has been widely studied. Yet, little is known about the neural substrate of high-level aspects of movement such as intention and awareness and how these functions are related to low-level movement execution processes. It has been suggested that the parietal cortex and supplementary motor area are involved in generating motor intentions, while premotor cortex may play a role in the emergence of motor awareness. However, the precise mechanisms implemented within each of these areas, the way they interact functionally and the nature of the signals conveyed to primary sensory and motor regions is far from being understood. Furthermore, intention and awareness of movement are also influenced by peripheral information coming from the skin, muscles and joints, and this information must be integrated to produce smooth, accurate and coordinated motor actions. Cortical and subcortical structures such as the primary motor cortex and the cerebellum are known to contain motor maps thought to contribute to motor control, learning and plasticity, but the intrinsic organization of these maps and the nature of their reciprocal relations are still unknown. In this thesis I used Direct Electrical Stimulation in patients undergoing brain surgeries to investigate how multiple motor representations are organized and identify the regions responsible for the emergence of conscious motor intention and awareness. I showed, in particular, the existence of multiple efferent maps within the cerebellum and the precentral gyrus. Furthermore, I identified the critical role of the parietal cortex for the emergence of conscious intention and -based on predictive processes- motor awareness. I also provided evidence that the premotor cortex is involved in "checking" parietal estimations, thus leading to a sense of "veridical awareness"
210

A Oferta do serviço ecossistêmico de regulação climática em florestas tropicais: o estado da arte e as implicações da conversão da floresta em campo antrópico / The climate regulation ecosystem service supply in tropical forest: the state of the art and the implications of forest conversion into pastureland

Caracena, Susana Elizabeth López 04 April 2019 (has links)
O serviço ecossistêmico de regulação climática global (SERCG) ofertado pelas florestas é reconhecido pelo seu papel crucial na mitigação da mudança climática. Tais ecossistemas atuam como sumidouros de carbono atmosférico por meio do CO2 sequestrado e armazenado nos tecidos vivos dos vegetais. Porém, processos de continuo desmatamento afetam negativamente a capacidade desses ecossistemas em ofertar o SERCG, especialmente em florestas tropicais que possuem alto potencial de ofertar o serviço e sofrem forte pressão devido ao desenvolvimento agroindustrial. As paisagens atlânticas brasileiras são exemplos dessa condição, em especial no estado de São Paulo, onde a vegetação natural foi primordialmente convertida em pastagens e silvicultura. Avaliar e gerenciar os estoques e fluxos de serviços dos ecossistemas em paisagens espacialmente heterogêneas constitui um dos principais desafios da ciência da sustentabilidade da paisagem. Frente a esse contexto, o presente estudo tem o objetivo de avaliar os estudos sobre a valoração ecológica do SERCG da floresta tropical e analisar a oferta deste serviço em paisagens atlânticas pressionadas pela atividade pecuária. Inicialmente, investigamos as tendências e lacunas que envolvem a pesquisa dos atributos biofísicos do SERCG nas florestas tropicais e subtropicais na escala pan-tropical através de uma revisão sistemática da literatura sobre o tema nos últimos 20 anos, de acordo com uma abordagem exploratória qualitativa. Constatamos que as estimativas de estoque de carbono das florestas tropicais apresentam alta variabilidade, que os fatores de influência mais recorrentes sobre o SERCG na literatura são as mudanças no uso da terra e a riqueza de espécies e que o SERCG possui maior número de relações de sinergia que de trade-off com outros SEs. Em um segundo momento, analisamos a oferta do serviço de regulação em paisagens atlânticas do Vale do Paraíba do Sul (SP), considerando o processo de substituição de floresta nativa por campo antrópico. Levantamos dados em campo para o cálculo de biomassa acima do solo de fragmentos florestais em diferentes estágios sucessionais e em campo antrópico, e transformamos esses dados em estoques de carbono. Os dados subsidiaram os cálculos de SERCG para 16 paisagens que tinham diferentes proporções de áreas de floresta e campo. Também avaliamos a influência da configuração da paisagem sobre a produção de biomassa dos remanescentes florestais. Obtivemos valores de estoque de carbono de 16,9±7,25 MgC há-1 para a floresta inicial, 34,8±12,05 MgC ha-1 para floresta intermediária-avançada e 0,53±0,26 MgC ha-1 para campo antrópico. Identificamos que a distância ao fragmento mais próximo diminui a biomassa das florestas em estágio inicial, enquanto a área média dos fragmentos localizados em um raio de 500 m ao redor do fragmento amostrado aumenta a biomassa das florestas em estágio intermediário-avançado. Destacamos o fato de que as paisagens avaliadas com > 40% do território florestado possuem um diferencial na contribuição da oferta do SERCG, devido ao aumento em número e área de fragmentos de floresta em estágio intermediário-avançado. Apesar do contraste entre a contribuição dos pequenos fragmentos em estágio inicial e os de estágio mais avançado, a ocorrência dos primeiros implica em uma maior oferta do SERCG em escala de paisagem. Ademais, a conservação desses fragmentos não só influenciaria na oferta do serviço de regulação climática, mas também na oferta de outros com os quais apresenta relações sinérgicas / The global climate regulation ecosystem service (GCRES) provided by forests is recognized for its crucial role in mitigating climate change. These ecosystems act as sinks of atmospheric carbon by sequestering and stocking CO2 in the living tissues of plants. However, continuous deforestation processes decreases its capacity to supply GCRES, especially in tropical forests which have high potential to provide the service and suffer strong pressure due to agroindustrial development. Brazilian Atlantic landscapes are examples of this condition, especially in the state of São Paulo, where natural vegetation was primarily converted into cattle pastures and forestry. Assessing and managing ecosystem services stocks and flows in spatially heterogeneous landscapes is one of the major challenges of landscape sustainability science. In this context, our objective is to evaluate the studies on the ecological valuation of GCRES in tropical forest and to analyse the supply of this service in Atlantic landscapes pressured by livestock activity. Initially, we investigated the trends and gaps that involve the biophysical attributes of GCRES in tropical and subtropical forest at a pan-tropical scale through a systematic review of the literature on the subject in the last 20 years, according to a qualitative exploratory approach. We found that (1) estimates of carbon stock from forests show high variability; (2) the most recurrent factors that influence on GCRES are land use and species richness; and (3) GCRES has a greater number of synergy relations with other SEs compared to trade-off relations. Secondly, we analysed the supply of the regulation service in Atlantic landscapes of the Paraiba do Sul Valley (SP, BR), considering the process of replacing native forest by pasturelands. We collected field data to calculate pasture and forest fragments aboveground biomass at different successional stages, and transformed these data into carbon stocks. This data subsidized the calculations of GCRES supply for 16 landscapes that had different proportions of forest and pasture areas. We also evaluated the influence of landscape configuration on forest remnants biomass production. We found carbon stock values of 16.9 ± 7.25 MgC ha-1 in initial forest, 34.8 ± 12.05 MgC ha-1 in intermediate-advanced forest and 0.53 ± 0.26 MgC ha-1 in cattle pastures. We identified that the distance to the nearest fragment decreases the early-stage forest biomass, while the average area of fragments located within a radius of 500 m around the sampled fragment increases the intermediate-advanced stage forest biomass. We highlight the fact that the evaluated landscapes with more than 40% of forested area have a differentiated contribution to the SERCG supply due to the increase in number and area of intermediate-advanced stage forest fragments. In spite of the contrast between the contribution of small fragments in the early stages and those of more advanced stage, the presence of the former implies a greater supply of SERCG at the landscape scale. In addition, the conservation of these fragments would not only influence the supply of the climate regulation service, but also the supply of other services with which it has synergistic relations

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