In Sweden, all employers are obligated to provide occupational health services that prevent and eliminate health risks in the workplace. Risk assessment is one of the recommended procedures of systematic work environment management that employers shall conduct to investigate the occurrence of workplace risks. However, implementation of systematic risk management tools might be challenging for employers because it requires certain organizational preconditions such as enough OHS skills, resources, management commitment or a good workplace climate because these preconditions might facilitate or hinder the implementation. To support the implementation of risk management tools, the organizational readiness for change can be assessed. This master's thesis was written in collaboration with LKAB, the Swedish company operating in the mining industry. Specifically, the aim was to assess the organizational readiness of the worksite LKAB Malmberget for initiating the implementation of the RAMP risk assessment tool. The organizational readiness was evaluated based on the modified theoretical model which was created by combining existing theoretical concepts about organizational readiness for change together with the findings from the empirical pre-study conducted with two ergonomists who worked with the RAMP tool implementation in the Swedish company Scania. The research method was a case study, the data were collected by semi-structured interviews and analysed through directed qualitative content analysis. The evaluation resulted in the identification of facilitating and hindering aspects of organizational readiness. The organizational facilitating factors for RAMP tool implementation were identified as - sufficient organizational resources for work environment activities; high management commitment to improving work environment; good organizational climate for employees' participation in work environment routines; well-integrated technological system for risk reporting; and workers' positive experience with previously done work environment changes. The organizational hindering aspects for RAMP tool implementation were identified as - the prevalence of reactive approach in the systematic work environment management; lack of usage of standardized risk assessment tools, lack of OHS expertise in the execution of the work environment routines; ergonomics was not integrated into the work environment management; top management's tendency to support work environment interventions with clear benefits and timelines. Finally, the evaluation of organizational readiness resulted in the development of practical recommendations for the worksite which could be supported and initiated for the RAMP tool implementation.

The major objective of this thesis was to investigate how the use of a recently developed microprocessor-controlled limb system altered the negative mechanical work done by the intact and prosthetic limb when trans-femoral amputees terminated gait. Participants terminated gait on a level surface from their self-selected walking speed and on declined surface from slow and customary speeds, using limb system prosthesis with microprocessor active or inactive. Limb negative work, determined as the integral of the negative mechanical (external) limb power during the braking phase, was compared across surface, speed and microprocessor conditions. Halting gait was achieved predominantly from negative work done by the trailing/intact. Trailing versus leading limb mechanical work imbalance was similar to how able body individuals halted gait. Importantly, the negative limb work performed on the prosthetic side when terminating gait on declined surface was increased when the microprocessor was active for both slow and customary speeds (no difference on level surface) but no change on intact limb. This indicates the limb system’s ‘ramp-descent mode’ effectively/dynamically altered the hydraulic resistances at the respective joints with evidence indicating changes at the ankle were the key factor for increasing the prosthetic limb negative work contribution. Findings suggest that trans-femoral amputees became more assured using their prosthetic limb to arrest body centre of mass velocity when the limb system’s microprocessor was active. More generally findings suggest, trans-femoral amputees should obtain clinically significant biomechanical benefits from using a limb system prosthesis for locomotion involving adapting to their everyday walking where adaptations to an endlessly changing environment are required. / Higher Committee of Education Development in IRAQ (HCED)

<p>Biomechanical and neural factors have both been suggested to contribute to the limited independence of finger movement and involuntary force production. The purpose of this study was to evaluate the degree of finger independence by examining the activity of the four compartments of extensor digitorum (ED) and flexor digitorum superficialis (FDS) using surface electromyography and involuntary force production in the non-task fingers using methods such as the “enslaving effect” (EE) and the “selectivity index” (SI). Twelve male participants performed a series of 5-second sub-maximal exertions at 5, 25, 50 and 75% of maximum using isometric isotonic and ramp finger flexion and extension exertions. Ramp exertions were performed from 0 to 85% of each finger’s maximum force with ascending and descending phases taking 4.5 seconds each with 0.5 seconds of plateau at 85%. Lower EE and higher SI (more selective force production) was found in flexion exertions compared to extension partially due to the higher activity of the antagonist ED compartments counterbalancing the involuntary activation of the non-task FDS compartments. Minimal FDS activity was seen during extension exertions. At forces up to and including 50%, both EE and muscle activity of the non-task compartments were significantly higher in descending exertions than the isotonic or ascending exertions. The selectivity index was also lower during the descending flexion and extension exertions at 25 and 50% MVC exertions. Up to mid-level forces, both finger proximity and contraction mode affects involuntary force production and muscle activation while at higher forces only finger proximity (and not the exertion mode) contributes to finger independence. The fingers were less selective at higher exertion levels (75% MVC) and all 3 exertion modes resulted in similar SI at 75% MVC in all flexion and extension exertions.</p> / Master of Science in Kinesiology

This thesis consists of five scientific articles oriented towards capacity. Managing capacity constraints with associated delays is a big issue at new design as well as at trimming existing traffic facilities. In larger Swedish cities these challenges have become more and more important as a result of growing traffic demand due to rapid population increase.Models for estimating capacity and delay are available, but not many are calibrated for Swedish conditions due to the high effort required. This thesis documents development and calibration of new models for motorway links, entry and exit lanes and weaving areas and an developed space-time model with the ability to calculate queue length, delay, etc.The first article is focused on identifying weaknesses in the former Swedish capacity method for motorways, and development of new models overcoming these shortcomings. The development includes new models for jam density at queue, capacity in weaving areas and fundamental flow-density relationships for 15 different highway types for inclusion in the new Swedish capacity manual.The second article describes the development of a Swedish motorway space-time model to estimate travel times and queues in oversaturated conditions based on the American FREEVAL model in Highway Capacity Manual 2010 (HCM 2010). Calibration and validation of the model has been performed with data from the Motorway Control System (MCS) in Stockholm. A good correspondence was obtained for most cases, but further calibration and validation efforts are required for entry and exit lanes.The third article describes further development of the intersection model in the Swedish microscopic model “Rural Traffic Simulator (RuTSim). This is a continuation of the work documented in the author’s licentiate thesis published in 2002. The development focused on simulation of intersections using a new concept on lane use not included in the old RuTSim model. The model describes Swedish rural intersections with flared approaches providing a non-discreet lane use due to vehicle types in queue. New data for calibration and validation data was also generated. The validation results showed good correspondence between simulated and empirical delay results. The new intersection model is now implemented in RuTSim, providing new tools for estimation of capacity, delay and queue length already included in Swedish guidelines and capacity manuals/software (Capcal).The fourth article describes the development of a new capacity model for roadwork zones. Focus is on the resulting capacity of one lane due to several reduction factors. These factors include impacts of closed road shoulders, reduction of number of lanes, diversion of traffic to the opposite carriageway, commuting traffic, length of work zone, lane width and type of road work. The first two correction factors were successfully validated in a full-scale test on the E6 motorway in Gothenburg.The fifth article describes development and implementation of a new harmonization algorithm for MCS systems on motorways designed to increase bottleneck capacity and throughput. Two different models were developed, one of which was implemented in the existing MCS system on E4 Södertäljevägen south of Stockholm. Full-scale trials were carried out with a model based on trigger levels in terms of flow. The second model based on the difference in the variance of speed during two following time periods was tested offline also with very good results. / <p>QC 20160429</p>

The overall aim of the present thesis is to clarify the control of intracellular chloride homeostasis in central neurons, because of the critical role of chloride ions (Cl–) for neuronal function. Normal function of the central nervous system (CNS) depends on a delicate balance between neuronal excitation and inhibition. Inhibition is, in the adult brain, most often mediated by the neurotransmitter γ-aminobutyric acid (GABA). GABA may, however, in some cases cause excitation. GABA acts by activating GABA type A receptors (GABAARs), which are ion channels largely permeable to Cl–. The effect of GABAAR-mediated neuronal signaling - inhibitory or excitatory - is therefore mainly determined by the Cl– gradient across the membrane. This gradient varies with neuronal activity and may be altered in pathological conditions. Thus, understanding Cl– regulation is important to comprehend neuronal function. This thesis is an attempt to clarify several unknown aspects of neuronal Cl– regulation. For such clarification, a sufficiently sensitive method for measuring the intracellular Cl– concentration, [Cl–]i, is necessary. In the first study of this thesis, we examined two electrophysiological methods commonly used to estimate [Cl–]i. Both methods, here called the interpolation and the voltage-ramp method, depend on an estimate of the Cl– equilibrium potential from the current-voltage relation of GABA- or glycine-evoked Cl– currents. Both methods also provide an estimate of the membrane Cl– conductance, gCl. With a combination of computational and electrophysiological techniques, we showed that the most common (interpolation) method failed to detect changes in [Cl–]i and gCl during prolonged GABA application, whereas the voltage-ramp method accurately detected such changes. Our analysis also provided an explanation as to why the two methods differ. In a second study, we clarified the role of the extracellular matrix (ECM) for the distribution of Cl– across the cell membrane of neurons from rat brain. It was recently proposed that immobile charges located within the ECM, rather than as previously thought cation-chloride transporter proteins, determine the low [Cl–]i which is critical to GABAAR-mediated inhibition. By using electrophysiological techniques to measure [Cl–]i, we showed that digestion of the ECM decreases the expression and function of the neuron-specific K+ Cl– cotransporter 2 (KCC2), which normally extrudes Cl- from the neuron, thus causing an increase in resting [Cl–]i. As a result of ECM degradation, the action of GABA may be transformed from inhibitory to excitatory. In a third study, we developed a method for quantifying the largely unknown resting Cl– (leak) conductance, gCl, and examined the role of gCl for the neuronal Cl– homeostasis. In isolated preoptic neurons from rat, resting gCl was about 6 % of total resting conductance, to a major part due to spontaneously open GABAARs and played an important role for recovery after a high Cl– load. We also showed that spontaneous, impulse-independent GABA release can significantly enhance recovery when the GABA responses are potentiated by the neurosteroid allopregnanolone. In a final commentary, we formulated the mathematical relation between Cl– conductance, KCC2-mediated Cl– extrusion capacity and steady-state [Cl–]i. In summary, the present thesis (i) clarifies how well common electrophysiological methods describe [Cl–]i and gCl, (ii) provides a novel method for quantifying gCl in cell membranes and (iii) clarifies the roles of the ECM, ion channels and ion transporters in the control of [Cl–]i homeostasis and GABAAR-mediated signaling in central neurons.

The primary objective of the study is to evaluate the safety performance of different freeway exit types used in current practical designs. More specific, the research objectives include the following two parts: 1) to compare the safety performance of different design types at freeway diverge areas and exit ramp sections; and 2) to identify the impact factors contributing to the crashes happening at these two specific segments. The study area includes four subjects, the freeway widely-spaced diverge areas; the freeway closely-spaced diverge areas; the left-side off-ramps and the exit ramp sections. For the freeway diverge areas, design types were defined based on the number of lanes used by vehicular traffic to exit freeways and lane-balance theory. Four exit ramp types were considered for the widely-spaced diverge area, including single-lane exit ramps (Type 1), sing-lane exit ramps without a taper (Type 2), two-lane exit ramps with an optional lane (Type 3), and two-lane exit ramps without an optional lane (Type 4). For the closely-spaced diverge areas, three types, named as Type A, Type B and Type C, are selected to compare the safety performances among the three types. For the left-side off-ramp at the freeway diverge area, this study examined the two most widely used design types at the left-side freeway diverge areas in Florida, which are defined as Type I (one-lane left-side off-ramp), and Type II (two-lane left-side off-ramp). Type I is comparable to Type 1 design type and Type II is comparable to Type 3 design type at widely-spaced freeway diverge area. For the exit ramp sections, four ramp configurations, including diamond, out connection, free-flow loop and parclo loop, were considered. Cross-sectional comparisons were conducted to compare the crash frequency, the crash rate, the crash severity and target crash types between different design groups. Crash predictive models were also built to quantify the impacts of various contributing factors. The results of this study would expectedly help transportation decision makers develop tailored technical guidelines governing the selection of the optimum design combinations at freeway diverge areas and exit ramp sections.

The Pennsylvanian Marble Falls Formation in the Llano Uplift region of the southern Fort Worth Basin (Central Texas) is a Morrowan-Atokan mixed carbonate-siliciclastic unit whose deposition was influenced by icehouse glacioeustatic sea-level fluctuations and foreland basin tectonics. Previous interpretations of the Marble Falls Formation focused on outcrop data at the fringes of the Llano Uplift. This study uses a series of 21 cores to create a facies architectural model, depositional environmental interpretation, and regional sequence stratigraphic framework. On the basis of core data, the study area is interpreted to have been deposited in a ramp setting with a shallower water upper ramp area to the south and a deeper water basin setting to the north. Analysis of cores and thin sections identified 14 inner ramp to basin facies. Dominant facies are: (1) burrowed sponge spicule packstone, (2) algal grain-dominated packstone to grainstone, (3) skeletal foraminiferal wackestone, and (4) argillaceous mudstone to clay shale. Facies stacking patterns were correlated and combined with chemostratigraphic data to improve interpretations of the unit’s depositional history and form an integrated regional model. The Marble Falls section was deposited during Pennsylvanian icehouse times in a part of the Fort Worth Basin with active horst and graben structures developing in response to the Ouachita Orogeny. The resulting depositional cycles reflect high-frequency sea-level fluctuations and are divided into 3 sequences. Sequence 1 represents aggradational ramp deposition truncated by a major glacioeustatic sea-level fall near the Morrowan-Atokan boundary (SB1). This fall shifted accommodation basinward and previously distal areas were sites of carbonate HST in Sequence 2 deposition following a short TST phase. Sequence 3 represents the final phase of carbonate accumulation that was diachronously drowned by Smithwick siliciclastics enhanced by horst and graben faulting. These findings contribute to our understanding of the depositional response to glacioeustatic sea-level changes during the Pennsylvanian and can also form the basis for constructing a sedimentological and facies analog for Morrowan to Atokan shallow- to deepwater carbonates in the Permian Basin and the northern Fort Worth Basin. / text

Made available in DSpace on 2016-06-02T20:19:08Z (GMT). No. of bitstreams: 1 DissANO.pdf: 2915693 bytes, checksum: a616909e56aa8b487546b0aff1e28427 (MD5) Previous issue date: 2004-04-29 / Universidade Federal de Minas Gerais / Purpose: quantify the anaerobic threshold (AT), by analysis of the response of heart rate (HR), surface electromyography (SEMG) and the ventilatory and metabolic variables, using mathematical methods and compare with ventilatory visual method to estimate the aerobic ability in hypertensive middle-aged man. Methods: nine middle-aged man (56,77 ± 2,81 years), active, with arterial hypertension, no medication, subject a baseline to control for evaluate the arterial blood pressure profile, was done three times a week during two weeks, in supine, seated and stand up position. Systolic blood pressure (SBP) was recorded in the appearing as the first sound (first-phase Korotkoff), and diastolic blood pressure (DBP), as the fifth sound (fifth-phase Korotkoff). All subjects were submit a performed ramp continuous dynamic physical exercise test (RCDPET), in electromagnetic cycloergometer (Corival 400) in 4 W during 4 minutes, follow up increment of 15 or 20 W/min, until exhaustion and/or sign limit. Heart rate was collected in real time, on a beat-to-beat basis (electrocardiogram ECAFIX TC500), during all RCDPET, vastus lateralis SEMG activity was collected continuous (Lynx Tecnology Eletronic Ltd) and the ventilatory and metabolic variables VO2 e VCO2 were also collected breath-bybreath quantification of ventilatory volumes and gas exchanges (CPX/D MedGraphics). Workload, heart rate (HR), VO2, VCO2 and surface electromyography (SEMG) analysis by 5 different methods: ventilatory visual graphic method (VVM) used with gold standard, linear-linear bissegmentar mathematical model method (LLMM) applied to carbon dioxide output data and Hinkley mathematical model method applied to heart rate data (HMM-HR), VCO2 data (HMMVCO2) and RMS index of SEMG activity data (HMM-RMS), who appoint exercise level in was to detect the AT. Workload, heart rate (HR), VO2, VCO2 and surface electromyography (SEMG) were statistical analysis to non-parametric tests were selected: Friedman test for repeated measures followed by post-hoc Dunn test for multiple comparisons and Spearman correlation test was also used. Significance level was set at 5%. Results: HMM-VCO2 model present significant difference (p<0,05) when compare with four methods (MVV, MMLL, HMM-FC and HMM-RMS) for values of workload. For values of VCO2 and heart rate, HMM-VCO2 model present significant differed (p<0,05) when compare with HMM-FC and HMM-RMS models; for values of VO2, HMM-VCO2 model present significant difference (p<0,05) when compare with MMLL, HMM-FC and HMM-RMS models. The HMM-VCO2 model present for all variables minor values in relation the MVV, MMLL, HMM-FC and HMM-RMS models. It was observed no significant correlations (p>0,05) when VVM (gold standard) model was correlation with LLMM (rs=0,56), HMM-HR (rs=0,40), HMM-VCO2 (rs=0,43) and HMM- RMS (rs=0,40) in AT power output values detected by the gold standard. However, it was observed significant correlations (p<0,05) in the correlation workload and VO2 (rs=0,75), and workload and HR (rs=0,69) values when utilize VVM (gold standard) model. Conclusions: the results found in the present investigation suggest that the mathematical models were effective in detecting the response pattern changes in variables (HR, VO2, VCO2 e RMS index of SEMG activity) detecting adequately the AT and the date of workload, heart rate 30 (HR), VO2, VCO2 and surface electromyographic (SEMG) analyze the HMM-VCO2 model present for all variables minor values, and this fact can be associated to hypertensive subjects have a increases in the sympathetic nervous system outflow and than might contribute to prevalence of anaerobic metabolism in the energetic production and this fact can be associated with different skeletal muscle fiber composition, with relative preponderance of glycolytic fast-twitch (type II-b) over oxidative fast-twitch (type II-a) or slow-twitch (type I) and than might contribute to impaired aerobic metabolism. The methodological limitation in this study in no carry out the biopsy to muscle, propose the continuation this topic in this study. / Objetivo:Determinar e correlacionar o limiar de anaerobiose a partir da resposta da freqüência cardíaca, do sinal eletromiográfico e das variáveis ventilatórias e metabólicas, utilizando metodologias matemáticas e compará-las com o método da análise visual gráfica das variáveis ventilatórias, para estimar a capacidade aeróbia em homens hipertensos de meia-idade. Metodologia: 9 homens de meia-idade (56,77 ± 2,81 anos), ativos ocupacionais, com hipertensão arterial, sem uso de medicamentos, submetidos a um período controle para o perfil da pressão arterial sistólica (PAS) e diastólica (PAD) de duas semanas com 3 medições semanais, nas posições supina, sentada e em pé. Os valores de PAS foram determinados no momento do aparecimento do primeiro som (fase I de Korotkoff) e os valores de PAD no desaparecimento do som (fase V de Korotkoff). Os mesmos, foram submetidos a um protocolo de teste de exercício físico dinâmico contínuo do tipo rampa (TEFDCR), realizado em cicloergômetro eletromagnético (Corival 400), com carga de 4 Watts (W) durante 4 minutos seguido de um incremento de potência de 15 ou 20 W/min, até a exaustão física e/ou sintoma limitado. Durante todo o TEFDC-R, a FC foi captada por meio de um monitor cardíaco (ECAFIX TC500), batimento a batimento em tempo real, o sinal eletromiográfico do músculo vasto lateral, foi coletado continuamente(Lynx Tecnologia Eletrônica Ltda), e as variáveis ventilatórias e metabólicas VO2 e VCO2 foram também coletadas respiração a respiração (ergoespirômetro CPX/D da marca MedGraphics). Os dados de potência, VO2, VCO2, FC e RMS do sinal da EMGs foram analisados por 05 diferentes metodologias que são: método do modelo visual gráfico ventilatório (MVV), o qual foi utilizado como padrão de referência, método do modelo matemático bissegmentado linear-linear (MMLL) aplicado aos dados de produção de gás carbônico (VCO2) e método do modelo matemático de Hinkley aplicado aos dados de FC (MMH-FC), VCO2 (MMH-VCO2) e RMS do sinal da EMGs (MMH-RMS), que indicaram o nível de exercício em que foi determinado o LA. Os valores de potência, VO2 , VCO2 , FC e RMS do sinal da EMGs foram analisados a partir dos testes estatísticos não paramétricos de Friedman para medidas repetidas seguido de técnica de comparação múltipla (post-hoc de Dunn) e teste de correlação de Spearman com nível de significância de &#945; = 5%. Resultados: para os valores de potência, o modelo MMH-VCO2 apresentou diferença estatisticamente significante (p<0,05) quando comparado com os 4 outros modelos de análise (MVV, MMLL, MMH-FC e MMHRMS). Houve diferença estatisticamente significante (p<0,05) para os valores de VCO2 e FC, entre o modelo MMH-VCO2 em relação aos modelos MMH-FC e MMHRMS; para o VO2 entre o modelo MMH-VCO2 em relação aos modelos MMLL, MMH-FC e MMH-RMS. O modelo MMH-VCO2 apresentou para todas as variáveis estudadas valores menores em relação aos valores determinados pelas outras metodologias. Não houve associação significativa (p<0,05) entre o modelo MVV e os modelos MMLL (rs=0,56), MMH-FC (rs=0,40), MMH-VCO2 (rs=0,43) e MMH-RMS (rs=0,40) para os valores de potência, analisados no nível em que foi determinado o LA. Porém, houve associação significativa entre potência e VO2 (rs=0,75) e entre potência e FC (rs=0,69) utilizando-se o modelo MVV considerado no presente estudo como padrão de referência. Conclusões: os resultados obtidos no presente estudo, 28 sugerem que os modelos matemáticos de análise mostraram-se sensíveis na determinação da mudança de padrão das respostas das variáveis estudadas (FC, VO2, VCO2 e RMS do sinal eletromiográfico), determinando adequadamente o limiar de anaerobiose, e que o modelo matemático de Hinkley aplicado aos dados de VCO2 apresentou-se sempre com menores valores, o que pode estar relacionado ao fato dos voluntários hipertensos estudados apresentarem aumento de atividade do sistema nervoso simpático, e isto pode contribuir para a predominância do metabolismo anaeróbio na produção de energia, que poderia estar relacionado com a composição das fibras musculo-esqueléticas, com predomínio de fibras de contração rápida glicolítica (tipo II-b) em relação a de contração rápida oxidativa(tipo II-a) e de contração lenta (tipo I) podendo resultar em prejuízo do metabolismo aeróbio. Devido a limitação metodológica da não realização de biópsia muscular no presente estudo, sugere-se a continuidade deste trabalho com o referido enfoque.

Made available in DSpace on 2015-03-13T17:08:23Z (GMT). No. of bitstreams: 1 RodrigoMP_ate Cap8.pdf: 2288926 bytes, checksum: 44bae2f6f3e55dec9ebd5707fbed042f (MD5) Previous issue date: 2005-09-16 / In spite of significant study and exploration of Potiguar Basin, easternmost Brazilian equatorial margin, by the oil industry, its still provides an interesting discussion about its origin and the mechanisms of hydrocarbon trapping. The mapping and interpretation of 3D seismic reflection data of Baixa Grande Fault, SW portion of Umbuzeiro Graben, points as responsible for basin architecture configuration an extensional deformational process. The fault geometry is the most important deformation boundary condition of the rift stata. The development of flat-ramp geometries is responsible for the formation of important extensional anticline folds, many of then hydrocarbon traps in this basin segment. The dominant extensional deformation in the studied area, marked by the development of normal faults developments, associated with structures indicative of obliquity suggests variations on the former regime of Potiguar Basin through a multiphase process. The changes in structural trend permits the generation of local transpression and transtension zones, which results in a complex deformation pattern displayed by the Potiguar basin sin-rift strata. Sismostratigraphic and log analysis show that the Baixa Grande Fault acts as listric growing fault at the sedimentation onset. The generation of a relay ramp between Baixa Grande Fault and Carnaubais Fault was probably responsible for the balance between subsidence and sedimentary influx taxes, inhibiting its growing behaviour. The sismosequences analysis s indicates that the extensional folds generation its diachronic, and then the folds can be both syn- and post-depositional / Apesar do significativo estudo e explora??o da Bacia Potiguar, extremo-leste da margem equatorial brasileira, pela ind?stria do petr?leo, a bacia ainda permite uma interessante discuss?o acerca de sua origem e dos mecanismos de trapeamento de hidrocarbonetos associados. O mapeamento e interpreta??o de dados de s?smica de reflex?o 3D da Falha de Baixa Grande, por??o SW do Graben de Umbuzeiro, aponta como respons?vel pela defini??o da arquitetura desta por??o da bacia um processo deformacional, essencialmente, distensional. A geometria da Falha de Baixa Grande ? a principal condi??o de contorno da deforma??o dos estratos sedimentares da fase sin-rifte da bacia. O desenvolvimento de geometrias do tipo flat-ramp ? respons?vel pela forma??o de importantes dobramentos distensionais anticlinais, muitos deles portadores de hidrocarbonetos neste segmento da bacia. A predominante deforma??o distensional na ?rea de estudo, marcada pelo desenvolvimento de falhas normais, associada a estruturas indicativas de obliq?idade, sugere varia??es no regime distensional formador da bacia Potiguar atrav?s de processos multif?sicos. A varia??o no trend estrutural ao longo da evolu??o da bacia permite a gera??o de zonas de comportamento local transtrativo e transpressivo, resultando no desenvolvimento do complexo padr?o deformacional impresso nos estratos da fase sin-rifte da Bacia Potiguar. An?lises sismoestratigr?ficas e de dados de po?os indicam que a Falha de Baixa Grande atuou como falha l?strica de crescimento nos primeiros epis?dios de sedimenta??o da bacia. A cria??o de uma rampa de revezamento entre as Falhas de Baixa Grande e Carnaubais foi, provavelmente, respons?vel pelo equil?brio entre as taxas de subsid?ncia e aporte sedimentar inibindo o funcionamento da falha como falha de crescimento. A an?lise de sismoseq??ncias permite, por fim, concluir que a gera??o dos dobramentos distensionais ? di?crona, podendo estes ser sin a p?s-deposicionais

[pt] Em obras ambientais, onde geossintéticos são utilizados como sistema de proteção e de cobertura de taludes, é de extrema importância o conhecimento do mecanismo de interação solo-geossintético, através da obtenção dos parâmetros de resistência da interface (adesão e ângulo de atrito da interface). O ensaio de laboratório mais adequado para a obtenção desses parâmetros, nestas condições, é o de cisalhamento em plano inclinado ou ensaio de rampa, pois permite simular a condição de campo onde o cisalhamento ocorre em um plano inclinado sob baixas tensões. Assim, este trabalho apresenta um estudo sobre a interação sologeossintético através de ensaios de rampa, executados em um equipamento de grandes dimensões, visando analisar a influência de alguns fatores, tais como, tipo de geossintético, tipo de solo, densidade relativa do solo e tensão confinante. Foram utilizados dois tipos de geossintéticos, uma geomembrana de PVC e uma geogrelha uniaxial e dois tipos de solo, areia e pedregulho (brita). A análise da influência da densidade relativa do solo foi realizada através de ensaios na interface areia-geossintético em duas densidades relativas diferentes (35 e 100%). A influência da tensão confinante foi estudada através de ensaios com três tensões confinantes distintas (2,1; 3,2 e 5,1 kPa). Os resultados mostram que a influência de fatores como densidade relativa do solo, tensão confinante e tipo de solo, dependem do tipo do geossintético. O aumento da densidade relativa do solo promove um acréscimo de resistência na interface para a geogrelha e uma redução para a geomembrana. O aumento da tensão confinante reduz o ângulo de rampa na ruptura, sendo este efeito mais pronunciado na interface areia-geogrelha. Em relação ao tipo de material, a interface brita-geogrelha é a que apresenta maior resistência. / [en] In environmental works, where geosynthetics are used as protection system and of slope covering, it is of extreme importance the knowledge of the interaction mechanism soil-geosynthetic, through the obtaining of the parameters of resistance of the interface (adhesion and interface friction angle). The laboratory test more appropriate for the obtaining of those parameters, in these conditions, is it the inclined plane test or ramp test, because it allows to simulate the field condition where the shearing happens in inclined plane under low tensions. Like this, this work presents a study about the interaction soilgeosynthetic through ramp tests, executed in an equipment of great dimensions seeking to analyze the influence of some factors, such as, geosynthetic type, soil type, relative density of the soil and confinement pressure. Two geosynthetics types, a PVC geomembrane and a uniaxial geogrid, two soil types, it sand and gravel (break). The analysis of the influence of the relative density of the soil was accomplished through tests in the interface sand- geosynthetic in two different relative densities (35 and 100%). The influence of the confinement pressure was studied through tests with three different confinement pressures (2,1; 3,2 and 5,1 kPa). The results show that the influence of factors as relative density of the soil, pressure confinement and soil type, they depend on the type of the geosynthetic. The increase of the relative density of the soil promotes an increment in the interface resistance for the geogrid and a reduction for the geomembrana. The increase of the confinement pressure reduces the ramp angle in the rupture, being this more pronounced effect in the interface sand-geogrid. In relation to the material type, the interface gravel-geogrid presents larger resistance.