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New high-quality multibeam and high-resolution seismic data reveal new observations on sediment transfer and distribution and margin morphometrics in the uppermost slope of Northeastern Little Bahama Bank between 20 and 300 m water depth. The echofacies/backscatter facies show an alongslope sediment distribution forming successive strips. The upper part of the uppermost slope corresponds to the alternation of several submerged coral terraces and escarpments that could be related to Late Quaternary sea-level variations. The terraces could either be related to periods of stagnating sea-level or slow-down in sea-level change and therefore increased erosion by waves, or periods of accelerated sea-level rise since the Last Glacial Maximum. Terraces could therefore be related to coral construction and drowing. The medium part corresponds to the marginal escarpment, a steep cemented area. The lower part of the uppermost slope shows a discontinuous Holocene sediment wedge with varying thickness between 0 and 35 m. It is separated from the upper part by a zone of well-cemented seafloor associated with the marginal escarpment. Passing cold fronts result in sediment export caused by density cascading. The associated sediment fall-out and convective sedimentation can generate density currents that form this wedge and eventually flow through linear structures on the upper slope. The survey reveals the presence of recently active channels that extend over the entire uppermost slope and interrupt the wedge. The channels connect shallow tidal channels to submarine valleys connected to the proximal part of canyons. They directly feed the canyons with platform-derived sediment forming low-density turbidity currents and could supply the deepest part of the system with coarse-grained sediment directly exported from the carbonate platform. [ABSTRACT FROM AUTHOR]

Sorption-based cooler is considered as an excellent candidate for the vibration-free cooling at cryogenic temperature. In a such cooler, the sorption compressor is the most critical module. To design a sorption-compressor, effective numerical models are essential which allow one to simulate the details of the heat and mass transfer within the sorption-compressor cell, predict the system performance and optimize various parameters. This paper presents a 1-dimensional dynamic model for a sorption-compressor cell, which is based on extensive adsorption-isotherm measurements and realistic thermal properties of materials at low temperatures. This numerical model combines the mass and energy equations while the momentum equation is skipped. It assumes the pressure to be uniform within the cell. However, the convection term in the energy equation is evaluated in this model with proper approximation without calculating the velocity field. A typical simulation case is presented to understand the details during a sorption compression that occur in the sorption-compressor cell. Experiments based on helium and neon operating at 77 K (liquid nitrogen temperature) were carried out to validate this model. The measured compressor performance was deviated from the simulation about 18%, but that is a reasonable inaccuracy for design propose and is well reasoned. Such 1-D dynamic model is qualified to be further used to design sorption compressor. [ABSTRACT FROM AUTHOR]

The aim of this study is to systematically review whether the presence of altered central pain modulation pre-surgical influences outcome after total knee replacement (TKR) in patients with knee osteoarthritis (OA), and if so which indices of central pain modulation predict poor outcome after TKR. To identify relevant articles, PubMed and Web of Science were searched. The search strategy was a combination of key words related to "Knee Osteoarthritis and Total Knee Replacement", "Central Pain Modulation" and "Post-Surgical Outcome Measures". Articles fulfilling the inclusion criteria were screened for methodological quality and results were analyzed and summarized. Sixteen prospective cohort studies were included. Strong evidence is available that presence of catastrophic thinking and poor coping strategies predict more pain after TKR and that there is no association between fear of movement and post-surgical pain or function. Evidence on other psychosocial influences is limited or conflicting. Literature on the influence of other signs of altered central pain modulation on post-surgical outcome is scarce. It is plausible that pre-surgical signs of altered central pain modulation, such as joint pain at rest or widespread pain sensitization, predict more post-surgical pain. Surgeons should be attentive for patients with signs of altered central pain modulation before surgery as they might be at risk for unfavorable outcome. A broader therapeutic approach aiming to desensitize the central nervous system can be adapted in these patients. Further research is however needed to identify the influence of central pain modulation pre-surgical in predicting outcome after TKR. [ABSTRACT FROM AUTHOR]

Abstract: The present study brings new insights on the small-scale characteristics of relatively distal turbidite deposits (classically defined as depositional lobes or sheets) from the deep-water clastic slope system of the Annot Sandstones (Grès d''Annot), in the Trois Evêchés area. This “seismic scale” outcrop has been studied in detail to characterize sedimentary geometries and facies associations within and between sheet-like sandstone-bodies. In terms of facies, their internal architecture is dominated by numerous erosional features, variable scale cross-bedding and dewatering structures. Facies range from gravelly sandstones to fine-grained sandstones and their spatial distribution inside sandstone-bodies is provided, allowing us to discuss the spatial changes in flow behaviour. A detailed dataset, made of very high-resolution correlations in thick to thin-bedded sheet-like sandstone-bodies, enables to identify five main types of architectural elements, composed of both channelised and unchannelised depositional bodies. Gravelly-filled channel-elements, laterally stacked channel-elements (interpreted as being related to sinuous channel migrations) and wing-like channel-elements constitute the channelised sheet systems whereas tabular sandstones (sheets sensu stricto), prograding and/or dome-shaped units constitute layered sheet systems. Sinuous channels are represented by the association of erosive-based, laterally stacked bedsets and very coarse-grained, low-angle cross-bedded facies. These latter facies are interpreted as the result of flow deconfinement and overbanks above channel margins. The stratigraphic relationships between these architectural elements permit establishing a conceptual model of the distribution and organisation of the components. This distribution scheme is based on the longitudinal differentiation of gravity processes, which are directly linked with architectural element types. This model is composed of proximal confined units where channelization processes, amalgamation and bypass dominate, to more distal and less confined units where compensation, constructive structures and high deposition rates control sedimentary architectures. The Trois Evêchés sub-basin may be considered as a good example of a channelised lobe to unchannelised lobe transitional environment, which explains the lateral and vertical high variability during its infill. The widespread apparition of residual facies, such as cross-stratified sandstones as well as basal lags, suggests significant bypass. The appearance of both channelised and unchannelised units is consistent with this transitional environment. The provided detailed dataset in this paper displays the associated wide range of architectural elements in these settings, and highlights the significant heterogeneities of sand-rich confined turbidite sheet systems. These heterogeneities are under the seismic resolution and may influence fluid migration in sand-rich deep-water reservoirs. [Copyright &y& Elsevier]

Abstract: Several types of sediment failures in the Gulf of Cadiz were observed using multibeam bathymetry, acoustic imagery and high-resolution seismic. These instabilities are mainly sediment failures and flows. Their width and length vary from 1 to more than 10km. The failures are mainly related to high sedimentation rates, particularly in places where the Mediterranean Outflow Water (MOW) spills over, such as channel bends and the outer side of the giant contourite levee. Steep slopes are also a trigger for failure at the continental shelf-slope transition, on valley sides, on canyon flanks, and on the sides of bathymetric highs. Other mass movements are related to fluid escape (mud volcanoes) and earthquakes. In areas where the MOW flows along the seafloor, the constant shearing and related erosion can add to the overall stresses. The frequency of failures can be estimated using the deposits resulting of their distal transformations into turbidites. [Copyright &y& Elsevier]

Abstract: A numerical model has been developed for the simulation of turbidity currents driven by nonuniform, non cohesive sediment and flowing over a complex three dimensional submarine topography. The model is based on an alternative approach known as Cellular Automata paradigm. The model is validated by comparing a simulation with a reported field-scale event. The chosen case is a turbidity current which occurred in Capbreton Canyon and was initiated by a storm in December 1999. Using data from recent oceanographic cruises, the deposit of the event has been precisely described, which constrain values of model parameters. The model simulates the 1999 turbidity current over the actual canyon topography and related turbidite using three different types of particle. The model successfully simulates areas of erosion and deposition in the canyon. It predicts the vertical and longitudinal grain size evolution, and shows that the fining-up sequence can be deposited by several phases of deposition and erosion related to the current energetic variation during its evolution. This result could explain the presence of intrabed contacts or the frequent lack of facies in Bouma sequences. [Copyright &y& Elsevier]

OBJECTIVE: To quantify the frequency of physical, cognitive, emotional, and behavioral changes as reported by patients and relatives after a stroke and to determine their degree of agreement. DESIGN: Follow-up study of 172 stroke patients to a mean of 9.8 months poststroke and 143 relatives interviewed separately with a questionnaire. SETTING: Home-based stroke patients. PARTICIPANTS: The 172 patients (107 men, 68 women) were a subset of 229 patients enrolled in a previous study. Their mean age +/- standard deviation was 55.3+/-10.9 years (age range, 18-70y). Other participants were 143 relatives (mostly spouses; 43 men, 100 women) had a mean age of 52.4+/-12.2 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Structured interview using a questionnaire. RESULTS: The overall percentage of frequency of different disturbances was comparable between patients' and relatives' reports. However, the degree of agreement between patients and their relatives tended to be low. Several possible explanations for this finding are considered, including the potential role of residuals of anosognosia in this stroke population. CONCLUSIONS: Educating families and rehabilitation specialists about the frequency of disturbances and possible reasons for different opinions between patients and families may provide useful information for therapeutic interventions. Copyright © 2005 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation [ABSTRACT FROM AUTHOR]

Objective: Our purpose was to investigate the value of plasma glutathione S-transferase Alpha 1-1 measurements in the assessment of hepatocellular damage in hypertensive disorders of pregnancy.Study Design: Patients were recruited at the Department of Obstetrics and Gynecology of the University Hospital, Nijmegen, The Netherlands. Five groups of patients were studied: normotensive pregnancy (n = 87), pregnancy-induced hypertension (n = 48), preeclampsia (n = 79), the syndrome of hemolysis, elevated liver enzymes, and low platelets (n = 39), and serially studied normotensive pregnancy (n = 21). Blood was collected for assessment of plasma glutathione S-transferase Alpha 1-1 levels and serum alanine aminotransferase activity. Levels in hypertensive pregnancies were compared with levels in normotensive pregnancy by the Mann-Whitney U test. Patients were categorized according as to whether their values are below (normal) or above (elevated) the upper normal reference level. The difference in relative magnitude of elevation between the two factors was determined by the Wilcoxon matched-pairs signed-rank test.Results: Plasma levels in the longitudinally studied normotensive pregnancy group did not differ between gestational ages and were not significantly different from those of the normotensive control group. Median levels of glutathione S-transferase Alpha 1-1 and alanine aminotransferase were significantly increased (p < 0.01, p < 0.0001, respectively) in all subgroups of hypertensive pregnancies compared with normotensive pregnancies. When both levels were elevated, the relative magnitude of the increase of glutathione S-transferase Alpha 1-1 levels was significantly higher than that of alanine aminotransferase activity in preeclampsia (p < 0.01) and the syndrome of hemolysis, elevated liver enzymes, and low platelets (p < 0.0001). Almost half the patients with preeclampsia showed elevated levels of alanine aminotransferase and/or glutathione S-transferase Alpha 1-1.Conclusion: Plasma glutathione S-transferase Alpha 1-1 measurements may provide a more sensitive indicator of acute hepatic damage in preeclampsia and the syndrome of hemolysis, elevated liver enzymes, and low platelets compared with the assessment of aminotransferase activity and therefore may allow earlier recognition of these syndromes. The clinical benefits of plasma measurements of glutathione S-transferase Alpha 1-1 for monitoring the hepatic condition in the management of these patients need to be elucidated in further studies. [ABSTRACT FROM AUTHOR]

The study of neuromuscular activity at very slow walking speeds may lead to a better understanding of the mechanisms underlying speed regulation during walking, and may aid the interpretation of gait data in patients who walk slowly. Extreme reductions in walking speed will cause changes in locomotor task demands that may eventually result in modifications of the patterning of muscle activity that underlies walking. The aim of the present study was to investigate patterns of lower limb muscle activity during very slow walking (<0.28 m s−1), and to study the neuromuscular gain functions that reflect the phase dependent effects of walking speed on electromyographic (EMG) amplitude. Nine healthy young adults walked at seven different walking speeds (1.39, 0.83, 0.28, 0.22, 0.17, 0.11, and 0.06 m s−1) while EMG was recorded from eight lower extremity muscles. Results showed that the phasing of muscle activity remained relatively stable over walking speeds despite substantial changes in its amplitude. However, between 1.39 and 0.28 m s−1, epochs of Rectus femoris, Biceps femoris and Tibialis anterior activities were found that were typical for specific speed ranges. When walking speed decreased further to almost standing still (0.06 m s−1), negative gain values were found in Peroneus longus during midstance and Rectus femoris in late swing, indicating the emergence of new bursts of activity with decreasing walking speed. It is proposed that these extra activities may be attributed to increased demands on postural stability, and the altered dynamics of the swinging limb at very slow speeds. [Copyright &y& Elsevier]

• 3D streamlines separating from downstream junction edge form a dividing surface. • Dividing surface delineates an open separation zone with a limited discharge. • 3D streamlines reveal different types of recirculating motions inside separation zone. • Classical delineation methods for separation zone proxies make simplifying assumptions on flow, yield reasonable maximum dimensions, but provide no physical insight. In the context of a T-shaped open-channel confluence, where the tributary flow separates at the downstream junction edge and creates a separation zone in the post-confluence channel, this paper provides a critical reflection upon the terminology and the delineation methods for the separation zone and its proxies: the recirculation zone and the reverse flow zone. Following the fluid-mechanical literature on flow separation, the separation zone is delineated by a dividing surface formed by the three-dimensional (3D) streamlines separating from the downstream junction edge. Based on a dense 3D time-averaged velocity field obtained from a Large-Eddy Simulation of a lab-style confluence flow, the separation zone turns out to be open. Near the bed, the dividing surface exhibits a gap, through which mainly tributary fluid enters the separation zone, leading to a limited discharge flowing through that zone. Downstream of the section where the merging flows are the most contracted, the dividing surface does not reattach to the inner bank, prohibiting the determination of a maximum length of the separation zone. Downstream of that section, the dividing surface gradually loses its role as a skeleton for the separation zone shear layer. Due to mixing, the separation zone and the adjacent maximum velocity zone gradually dissolve and transform into the flow recovery zone, as in a wake. By means of flow visualization with 3D streamlines, revealing different types of recirculating motions, the maximum recirculation zone extent is determined. Then three simplified methods commonly used in the literature to quantify the dimensions of the separation zone or its proxies are evaluated by comparison with the 3D streamline method. By adopting various simplifying assumptions about the flow, the pseudo-streamline method, the zero-unit-discharge method and the zero-velocity method yield definite reasonable maximum lengths for the recirculation zone and the reverse flow zone. With the exception of the zero-velocity method, all simplified methods yield reasonable estimates for the maximum widths and the corresponding contraction coefficients of the separation zone proxies. Still, contrary to the simplified methods, only the 3D streamline method can provide physical insight into the flow features occurring in the separation zone or its proxies. [ABSTRACT FROM AUTHOR]

The Danube Deep-Sea Fan (NW Black Sea) is one of the most developed deep-sea sediment depositional systems in Europe. Although the morphology and the architecture have been widely described in the past years, little is known about the stratigraphy of this depositional system. For the late Quaternary, this results from the lack of significant stratigraphic markers, the scarcity of radiocarbon ages and the difficulty in constraining reservoir ages. Recent robust quantification of reservoir ages has allowed the construction of a new stratigraphic framework for the Black Sea from the end of the last glacial period to the Holocene, thus giving the opportunity to correlate sedimentological and geochemical features previously described on the NW Black Sea margin with climatic events identified in the Northern Hemisphere. Based on this approach, we propose an improved chrono-lithostratigraphic framework for the Danube Deep-Sea Fan channel–levees since the Last Glacial Maximum. We show that the Danube Deep-Sea Fan was active during the Last Glacial Maximum until the Younger Dryas–Early Holocene transition ca. 11,700 cal a. BP, when the turbidite activity abruptly terminated in the whole system. Throughout this period, the Danube River was the main source of the deep depositional system, except between ca. 17,200 cal a. BP and 15,700 ± 300 cal a. BP. At that time, the deposition of ‘red turbidites’ in the deep basin, concomitant with the deposition of the so-called ‘Red Layers’ onto the continental shelf and the upper slope, emphasises the direct impact of the increased meltwater runoff of the Dnieper River as far as the Danube Deep-Sea Fan. Some significant changes in the location of the depocentre of the Danube Deep-Sea Fan occurred through time. The main change in depocentre location occurred at ca. 28,000 cal a. BP, with the northward avulsion leading to the formation of the Middle Channel. Although the Middle and Northern Channel became the preferential turbidite depocentres after this event, the deposition of turbidites has persisted in the Southern channel–levee until 14,700 cal a. BP, indicating that the Southern Channel was definitely not abandoned after the upstream northward avulsion. Unsurprisingly, water-level fluctuations and river sediment flux acted as the main forcings on the evolution of the Danube Deep-Sea Fan. Based on these results, and on the morphology of the Danube Canyon, we propose that ( i ) lowstand conditions (≤ − 110 m) prevailed during the Last Glacial Maximum, and possibly between 15,700 ± 300 cal a. BP and 14,700 cal a. BP, ( ii ) water-level ranged from ≥ − 110 and ≤ − 70 m between 14,700 and 11,700 cal a. BP, and ( iii ) water-level ranged from ≥ − 70 and ≤ − 30 m from 11,700 cal a. BP and until the reconnection of the Black Sea ‘Lake’ with the global ocean at ca. 9000 cal a. BP. [ABSTRACT FROM AUTHOR]

Foraminifera and ostracods have been quantitatively studied in core MD01-2472, from the upper continental slope (at water depth of 501 m), to evaluate their relationship with bottom water condition variability and decipher the control of the Levantine Intermediate Water (LIW) current on benthic faunas. The occurrence of reworked ostracod species (originating from the continental shelf) and, the presence of shallow water Elphidium/Ammonia benthic foraminifera are used to estimate the degree of along-slope transport at the core site. This has revealed two intervals of along-slope transport also associated with coarse-grained contourite deposits, deposited during the YD and HS2 episodes. Planktonic-benthic foraminiferal and ostracod assemblages reflect climate oscillations. Peaks of the polar planktonic Neogloboquadrina pachyderma (left-coiling S) may be used to identify Heinrich Events. Interstadials are marked by abundant ostracod species such as Paracypris sp., Argilloecia acuminata , and Cytheropteron alatum and the presence of benthic foraminifera like Bulimina marginata , Bulimina costata and Gyroidina altiformis . The B–A and Holocene are characterized by abundant warm water species of planktonic foraminifera and by the ostracod species Polycope sp. We hypothesize that there is relationship between LIW intensification during cold rapid climate events and benthic fauna assemblage variations due to changes in: 1) bottom water ventilation; and 2) the export of nutrients and/or sediment particles by bottom currents. [ABSTRACT FROM AUTHOR]

Abstract: Cellular automata (CA) represent an interesting approach to the modelling of dynamical systems evolving on the basis of local interactions and internal transformations. The CA model, specially developed for simulating density currents, is described. The objective is to predict the formation and evolution of channels and the structure of deposits associated to the flow path. For simulation purposes, currents are represented as a dynamical system subdivided into elementary parts, whose state evolves as a consequence of local interactions and internal transformations within a spatial discrete domain. The model is developed for unsteady, two-dimensional, depth-averaged, particle-laden turbulent underflows driven by gravity, acting on density gradients created by non-uniform and non-cohesive sediment. CA is defined as a tessellation of finite-state automata (cells). The attributes of each cell (substates) describe physical characteristics. The natural phenomenon is decomposed into a number of elementary processes, with a particular composition that makes up the transition function of the CA. By applying this function to all the cells simultaneously, the evolution of the phenomenon can be simulated in terms of modification of the substates. The transition function includes the effects of water incorporation at the suspension–ambient fluid interface, a transport equation for the particle volume concentration, and a toppling rule for the deposited sediments. Simple and flexible, the obtained model constitutes a first step toward quantitative comprehension of the impact of external parameters on the turbidity current dynamics and on the organisation of the subsequent depositional sequences. [Copyright &y& Elsevier]

OBJECTIVE: To determine the effects on energy expenditure, health and fitness outcomes in sedentary older adults aged 55-65 after 6-month participation in the GALM program. METHODS: In three Dutch communities, subjects from matched neighbourhoods were assigned to an intervention (n = 79) or a waiting-list control group (n = 102). The GALM program consisted of fifteen 60 min sessions once a week emphasising moderate-intensity recreational sports activities. RESULTS: The intervention group showed significant increases in energy expenditure for recreational sports activities, other leisure-time physical activity, health indicators, and perceived and performance-based fitness. Contrary to our expectations, the same increases were found for the control group. Consequently, only significant between-group differences, favouring the intervention group, were obtained for sleep, diastolic blood pressure, perceived fitness score and grip strength. CONCLUSION: The increases in energy expenditure for physical activity from the GALM program, especially for the more intensive recreational sports activities, look promising and are in line with the expected amounts necessary to improve health. Further research is needed to evaluate long-term effects of participation in the GALM program. PRACTICE IMPLICATIONS: These results underline that GALM can be considered successful in stimulating leisure-time physical activity and improving health and fitness in older adults. [ABSTRACT FROM AUTHOR]

Abstract: The Rhône Deep Sea Fan is the largest sedimentary body in the western Mediterranean Sea. We present here the results of a detailed geophysical and sedimentological analysis of the most recent gravity deposits situated on the western flank of this large sedimentary body. These results are based on the interpretation of seismic profiles as well as acoustic and coring data acquired during the MARION cruise conducted in 2000 onboard R/V Le Suroît and Images V cruise on board of the R/V Marion Dufresne (1999). We found that (1) a new channel-levee unit developed during the last stage of the Rhône Neofan evolution and (2) the last phase of up-building of this channel/levee system dates back to 15.1kaBP (14C). This implies that the last lobe of the Rhône deep-sea fan was built during the last low sea-level and the ensuing sea-level rise. We also identified (3) 10 recent sandy deposits, previously interpreted as related to the Neofan activity. In fact, their origin is probably linked to the Sète canyon that collect sandy shelf-edge deposits remobilised at the head of the Pyreneo-Languedocian canyons. We also characterised (4) the morphology and discuss the origin of the scours previously identified in the study area. These results contrast with previous interpretation which assigned a much younger age to the Neofan (). [Copyright &y& Elsevier]