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Resumo Objetivo Descrever a técnica e os resultados da artroscopia no tratamento cirúrgico dos cistos sinoviais volares no punho. Materiais e Métodos Foram incluídos e analisados neste trabalho 21 pacientes submetidos a artroscopia para o tratamento de cisto sinovial volar no punho, no período entre janeiro de 2015 e maio de 2017, com avaliação completa e mínima de 6 meses. A técnica descrita foi indicada para os pacientes com dor e incapacidade funcional com duração de mais de quatro meses, sem melhora com o tratamento conservador, ou para aqueles com queixas estéticas e que apresentavam o cisto havia mais de três meses. Resultados A média de idade dos pacientes foi de 43,6 anos, sendo 16 (76%) do sexo feminino, e 5 (24%) do masculino. O tempo de seguimento médio entre a cirurgia e a avaliação final foi de 10,9 meses. Um total de 2 (9,6%) pacientes apresentaram dor leve e uma restrição da mobilidade no pós-operatório. Nos 18 (90,4%) pacientes restantes, houve melhora das queixas estéticas, recuperação funcional completa, e melhora completa da dor. Não houve recidivas ou infecções. Nenhum paciente necessitou ser submetido a nova cirurgia. Conclusões A ressecção artroscópica do cisto sinovial volar mostrou-se uma técnica útil e segura. É um procedimento minimamente invasivo, com baixa morbidade e poucas complicações, sendo uma boa alternativa à técnica aberta.

Resumo Objetivo Descrever os resultados do tratamento cirurgico de pacientes portadores de artrogripose congenita com deformidade do punho atraves da osteotomia intracarpica biplanar. Metodo Por meio de uma avaliacao retrospectiva, entre janeiro de 2004 e dezembro de 2009, o estudo avaliou nove pacientes com grave deformidade em flexao e desvio ulnar do punho por artrogripose submetidos a osteotomia intracarpica com cunha de resseccao dorsal biplanar, com avaliacao minima de 48 meses de evolucao pos‐operatoria. Em tres pacientes, a osteotomia foi bilateral, perfez 12 punhos analisados. A indicacao da tecnica descrita foi deformidade e rigidez havia mais de seis meses, sem melhoria com tratamento conservador. Resultados A media de idade dos pacientes no dia da cirurgia foi de cinco anos e oito meses. A media de mobilidade inicial do punho foi de 35° e as articulacoes apresentavam 72,5° de flexao media em posicao de repouso. Todas osteotomias consolidaram em um periodo medio de 5,7 semanas. A media da posicao final do punho em repouso foi de 12° de flexao e a mobilidade media foi de 26,6°, ligeiramente inferior ao pre‐operatorio, porem mais bem posicionado. Nao foram observadas complicacoes graves decorrentes da cirurgia ou no pos‐operatorio imediato. Conclusoes A osteotomia intracarpica com cunha de resseccao dorsal biplanar se mostrou util e eficaz no auxilio da correcao da deformidade em flexao e desvio ulnar do punho, com manutencao de uma mobilidade razoavel. E uma cirurgia preservadora, com baixa morbidade e que evita a progressao da deformidade e alteracoes degenerativas futuras.

Objective: To describe the results of the surgical treatment of patients with congenital arthrogryposis with wrist deformity through biplanar carpal wedge osteotomy. Method: This study analyzed nine patients through a retrospective evaluation with severe deformity in flexion and ulnar deviation of the wrist in the period between January 2004 and December 2009. They were submitted to carpal osteotomy with a biplanar dorsal resection wedge, with a minimum evaluation of 48 months of postoperative evolution. In three patients the osteotomy was bilateral, totalling 12 cuffs analyzed. The indication for the technique described was deformity and stiffness for over six months, without improvement with the conservative treatment. Results: The mean age of the patients on the day of surgery was five years and eight months. The initial mean wrist mobility was 35°, and the joints presented a mean flexion of 72.5° in a resting position. Osteotomy union occurred in all patients at an average period of 5.7 weeks. The final position of the resting wrist was 12° of flexion and the mean mobility was 26.6°, slightly lower than preoperatively but in a much better position. No serious complications arising from surgery or in the immediate postoperative period were observed. Conclusions: Carpal osteotomy with biplanar dorsal resection wedge was useful and effective in helping to correct the deformities in flexion and ulnar deviation of the wrist, maintaining a reasonable mobility. It is a preservation surgery, which has low morbidity and avoids the progression of deformity and future degenerative changes. RESUMO Objetivo: Descrever os resultados do tratamento cirúrgico de pacientes portadores de artrogripose congênita com deformidade do punho através da osteotomia intracárpica biplanar. Método: Por meio de uma avaliação retrospectiva, entre janeiro de 2004 e dezembro de 2009, o estudo avaliou nove pacientes com grave deformidade em flexão e desvio ulnar do punho por artrogripose submetidos a osteotomia intracárpica com cunha de ressecção dorsal biplanar, com avaliação mínima de 48 meses de evolução pós-operatória. Em três pacientes, a osteotomia foi bilateral, perfez 12 punhos analisados. A indicação da técnica descrita foi deformidade e rigidez havia mais de seis meses, sem melhoria com tratamento conservador. Resultados: A média de idade dos pacientes no dia da cirurgia foi de cinco anos e oito meses. A média de mobilidade inicial do punho foi de 35° e as articulações apresentavam 72,5° de flexão média em posição de repouso. Todas osteotomias consolidaram em um período médio de 5,7 semanas. A média da posição final do punho em repouso foi de 12° de flexão e a mobilidade média foi de 26,6°, ligeiramente inferior ao pré-operatório, porém mais bem posicionado. Não foram observadas complicações graves decorrentes da cirurgia ou no pós-operatório imediato. Conclusões: A osteotomia intracárpica com cunha de ressecção dorsal biplanar se mostrou útil e eficaz no auxílio da correção da deformidade em flexão e desvio ulnar do punho, com manutenção de uma mobilidade razoável. É uma cirurgia preservadora, com baixa morbidade e que evita a progressão da deformidade e alterações degenerativas futuras.

The magnitude of epikarstic water storage variation is evaluated in various karst settings using a relative spring gravimeter. Gravity measurements are performed over a 1.5-year period at the surface and inside caves at different depths on three karst hydro-systems in southern France: two limestone karst systems and one dolomite karst system. We find that significant water storage variations occur in the first 10 m of karst unsaturated zone. The subsurface water storage is also evidenced by complementary magnetic resonance sounding. The comparison between sites of the depth gravity measurements with respect to net water inflow suggests that seasonal water storage depends on the lithology. The transmissive function of the epikarst on the seasonal scale has been deduced from the water storage change estimation. Long (> 6 months) and short (

In this study we attempt to evaluate the magnitude of epikarstic water storage variation in various karst settings using a relative spring gravimeter. Gravity measurements are performed two times a year at the surface and inside caves at different depths on three karst aquifers in southern France: two limestone karst systems and one dolomite karst system. We find that water storage variations occur mainly in the first ten meters of karst unsaturated zone. Afterward, surface to depth gravity measurements are compared between the sites with respect of net water inflow. A difference of seasonal water storage is evidenced probably associated with the lithology. The transmissive function of the epikarst has been partially deduced from the water storage change estimation. Long (> 6 months) and short (

In this paper we present the potential of a new compact superconducting gravimeter (GWR iGrav) designed for groundwater monitoring. At first, 3 yr of continuous gravity data are evaluated and the performance of the instrument is investigated. With repeated absolute gravity measurements using a Micro-g Lacoste FG5, the calibration factor (−894.8 nm s−2 V−1) and the long-term drift of this instrument (45 nm s−2 yr−1) are estimated for the first time with a high precision and found to be respectively constant and linear for this particular iGrav. The low noise level performance is found similar to those of previous superconducting gravimeters and leads to gravity residuals coherent with local hydrology. The iGrav is located in a fully instrumented hydrogeophysical observatory on the Durzon karstic basin (Larzac plateau, south of France). Rain gauges and a flux tower (evapo-transpiration measurements) are used to evaluate the groundwater mass balance at the local scale. Water mass balance demonstrates that the karst is only capacitive: all the rainwater is temporarily stored in the matrix and fast transfers to the spring through fractures are insignificant in this area. Moreover, the upper part of the karst around the observatory appears to be representative of slow transfer of the whole catchment. Indeed, slow transfer estimated on the site fully supports the low-flow discharge at the only spring which represents all groundwater outflows from the catchment. In the last part of the paper, reservoir models are used to characterize the water transfer and storage processes. Particular highlights are done on the advantages of continuous gravity data (compared to repeated campaigns) and on the importance of local accurate meteorological data to limit misinterpretation of the gravity observations. The results are complementary with previous studies at the basin scale and show a clear potential for continuous gravity time-series assimilation in hydrological simulations, even on heterogeneous karstic systems.

OBJECTIVE: The presence of a lesion with atypical presentation, obscure clinical history, which does not improve with classic treatments, shall raise the red flag of the medical team. In such cases, the hypothesis of a factitious lesion shall be considered. Many times the correct diagnosis on the initial assessment may avoid high-cost diagnostic tests, unnecessary treatments, and time consumption of the medical team. We present here two classic cases of factitious lesions that, similar to those described in the literature, is difficult to diagnose and difficult to treat. OBJETIVO: A presença de lesão com apresentação atípica, história clínica indefinida, que não melhora com tratamentos clássicos, deve colocar a equipe médica em alerta. Nesses casos, a hipótese de lesão factícia tem de ser levada em conta. Muitas vezes o diagnóstico correto na avaliação inicial pode evitar a realização de testes diagnósticos de alto custo, tratamentos desnecessários e desgaste da equipe médica. Por meio da apresentação de dois casos clássicos de lesão factícia na mão mostramos que, assim como descrito na literatura, tal patologia é de difícil diagnóstico e tratamento.

The Bureau International des Poids et Mesures (BIPM), Sèvres, France, hosted the 7th International Comparison of Absolute Gravimeters (ICAG) and the associated Relative Gravity Campaign (RGC) from August to September 2005. ICAG 2005 was prepared and performed as a metrological pilot study, which aimed: (1) To determine the gravity comparison reference values; (2) To determine the offsets of the absolute gravimeters; and (3) As a pilot study to accumulate experience for the CIPM Key Comparisons. This document presents a complete and extensive review of the technical protocol and data processing procedures. The 1st ICAG–RGC comparison was held at the BIPM in 1980–1981 and since then meetings have been organized every 4 years. In this paper, we present an overview of how the meeting was organized, the conditions of BIPM gravimetric sites, technical specifications, data processing strategy and an analysis of the final results. This 7th ICAG final report supersedes all previously published reports. Readings were obtained from participating instruments, 19 absolute gravimeters and 15 relative gravimeters. Precise levelling measurements were carried out and all measurements were performed on the BIPM micro-gravity network which was specifically designed for the comparison.

A network of 54 survey GPS sites, 28 continuous GPS stations and three absolute gravity (AG) observation sites have been set up in the Alborz mountain range to quantify the present-day kinematics of the range. Our results allow us to accurately estimate the motion of the South Caspian block (SCB) for the first time, and indicate rotation of the SCB relative to Eurasia, accounting for the left lateral motion in the Alborz range. In light of these new results, it clearly appears that deformation rates vary along the range, the eastern part accommodating mainly left lateral strike slip (2 mm yr(-1) south of the range and 5 mm yr(-1) north of the range) with a very low range normal shortening rate on the Khazar thrust fault (similar to 2 mm yr(-1)), and the western part accommodating range normal shortening (similar to 6 mm yr-1) on the Khazar thrust fault with a left lateral component of similar to 2 mm yr(-1) north of the range and 1 mm yr(-1) south of the range. These present-day kinematics agree with geomorphologic estimated slip rates, but not the long-term deformation, corroborating the idea that the kinematics of the range have changed recently due to the change of SCB motion.;Modelling of the interseismic deformation suggests a deep locking depth on the central-western segment of the Khazar fault (similar to 30 km) in agreement with the Baladeh earthquake rupture and aftershock ranging between 10 and 30 km. Given this unusual deep locking depth and the 34 degrees dip of the thrust, a large part of the Alborz range is located above the seismically coupled part of the fault. Based on our AG measurements this part of the range seems to uplift at a rate of 1-5 mm yr(-1), in agreement with terrace uplift.

International audience; In this study we attempt to understand the water storage variations in a karst aquifer on the Larzac Plateau (South of France) using ground-based gravimetry. Surface to 60 m depth gravity measurements are performed three times a year since 2006 down a pothole, in complement to monthly absolute gravity (AG) measurements at three sites. The time variations of the surface to depth (STD) gravity differences are compared with the AG variations. Using a simple Bouguer plate model, we find that the STD gravity differences are very similar to the AG variations. The STD gravity differences are then used to determine apparent density values. These integrative density values are compared with measured grain densities from core samples to obtain an apparent porosity and saturation change representative of the investigated depth. The apparent porosity ranges from 4.8 to 7.3 per cent. We then discuss on the repartition of the apparent physical properties with respect to the epikarst and infiltration zone karst structures. We argue that AG and STD differences monitor epikarst water storage variations. Within this scope, we discuss the fact that seasonal scale water storage variation occurs predominantly in the epikarst.

The Alborz is a narrow (100 km) and elevated (3000 m) mountain belt which accommodates the differential motion between the Sanandaj–Sirjan zone in central Iran and the South Caspian basin. GPS measurements of 12 geodetic sites in Central Alborz between 2000 and 2002 allow to constrain the motion of the belt with respect to western Eurasia. One site velocity on the Caspian shoreline suggests that the South Caspian basin moves northwest at a rate of 6±2 mm/year with respect to western Eurasia. North–South shortening across the Alborz occurs at 5±2 mm/year. To the South, deformation seems to extend beyond the piedmont area, probably due to active thrusting on the Pishva fault. We also observe a left-lateral shear of the overall belt at a rate of 4±2 mm/year, consistent with the geological motion observed along E–W active strike-slip faults inside the belt (e.g., the Mosha fault).

SUMMARY A network of 27 GPS sites was implemented in Iran and northern Oman to measure displacements in this part of the Alpine‐Himalayan mountain belt. We present and interpret the results of two surveys performed in 1999 September and 2001 October. GPS sites in Oman show northward motion of the Arabian Plate relative to Eurasia slower than the NUVEL-1A estimates (e.g. 22 ± 2m m yr −1 at N8 ◦ ± 5 ◦ E instead of 30.5 mm yr −1 at N6 ◦ E at Bahrain longitude). We define a GPS Arabia‐Eurasia Euler vector of 27.9 ◦ ± 0.5 ◦ N, 19.5 ◦ ± 1.4 ◦ E, 0.41 ◦ ± 0.1 ◦ Myr −1 . The Arabia‐Eurasia convergence is accommodated differently in eastern and western Iran. East of 58 ◦ E, most of the shortening is accommodated by the Makran subduction zone (19.5 ± 2m m yr −1 ) and less by the Kopet-Dag (6.5 ± 2m m yr −1 ). West of 58 ◦ E, the deformation is distributed in separate fold and thrust belts. At the longitude of Tehran, the Zagros and the Alborz mountain ranges accommodate 6.5 ± 2m m yr −1 and 8 ± 2m m yr −1 respectively. The right-lateral displacement along the Main Recent Fault in the northern Zagros is about 3 ± 2m m yr −1 , smaller than what was generally expected. By contrast, large rightlateral displacement takes place in northwestern Iran (up to 8 ± mm yr −1 ). The Central Iranian Block is characterized by coherent plate motion (internal deformation < 2m m yr −1 ). Sites east of 61 ◦ E show very low displacements relative to Eurasia. The kinematic contrast between eastern and western Iran is accommodated by strike-slip motions along the Lut Block. To the south, the transition zone between Zagros and Makran is under transpression with right-lateral displacements of 11 ± 2m m yr −1 .

The rate of crustal deformation in Iran due to the Arabia–Eurasia collision is estimated. The results are based on new global positioning system (GPS) data. In order to address the problem of the distribution of the deformation in Iran, Iranian and French research organizations have carried out the first large-scale GPS survey of Iran. A GPS network of 28 sites (25 in Iran, two in Oman and one in Uzbekistan) has been installed and surveyed twice, in September 1999 and October 2001. Each site has been surveyed for a minimum observation of 4 days. GPS data processing has been done using the GAMIT-GLOBK software package. The solution displays horizontal repeatabilities of about 1.2 mm in 1999 and 2001. The resulting velocities allow us to constrain the kinematics of the Iranian tectonic blocks. These velocities are given in ITRF2000 and also relative to Eurasia. This last kinematic model demonstrates that (1) the north–south shortening from Arabia to Eurasia is 2–2.5 cm/year, less than previously estimated, and (2) the transition from subduction (Makran) to collision (Zagros) is very sharp and governs the different styles of deformation observed in Iran. In the eastern part of Iran, most of the shortening is accommodated in the Gulf of Oman, while in the western part the shortening is more distributed from south to north. The large faults surrounding the Lut block accommodate most of the subduction–collision transition.

This paper introduces a new approach to airborne gravity data reduction well‐suited for surveys flown at high altitude with respect to gravity sources (mountainous areas). Classical technique is reviewed and illustrated in taking advantage of airborne gravity measurements performed over the western French Alps by using a LaCoste & Romberg air‐sea gravity meter. The part of nongravitational vertical accelerations correlated with gravity meter measurements are investigated with the help of coherence spectra. Beam velocity has proved to be strikingly correlated with vertical acceleration of the aircraft. This finding is theoretically argued by solving the equation of the gravimetric system (gravity meter and stabilized platform). The transfer function of the system is derived, and a new formulation of airborne gravity data reduction, which takes care of the sensitive response of spring tension to observable gravity field wavelengths, is given. The resulting gravity signal exhibits a residual noise caused by electronic devices and short‐wavelength Eötvös effects. The use of dedicated exponential filters gives us a way to eliminate these high‐frequency effects. Examples of the resulting free‐air anomaly at 5100‐m altitude along one particular profile are given and compared with free‐air anomaly deduced from the classical method for processing airborne gravity data, and with upward‐continued ground gravity data. The well‐known trade‐off between accuracy and resolution is discussed in the context of a mountainous area.

International audience; The Western Alps are among the best studied collisional belts with both detailed structural mapping and also crustal geophysical investigations such as the ECORS and EGT seismic profile. By contrast, the present-day kinematics of the belt is still largely unknown due to small relative motions and the insufficient accuracy of the triangulation data. As a consequence, several tectonic problems still remain to be solved, such as the amount of N-S convergence in the Occidental Alps, the repartition of the deformation between the Alpine tectonic units, and the relation between deformation and rotation across the Alpine arc. In order to address these problems, the GPS ALPES group, made up of French, Swiss and Italian research organizations, has achieved the first large-scale GPS surveys of the Western Alps. More than 60 sites were surveyed in 1993 and 1998 with a minimum observation of 3 days at each site. GPS data processing has been done by three independent teams using different software. The different solutions have horizontal repeatabilities (N-E) of 4-7 mm in 1993 and 2-3 mm in 1998 and compare at the 3-5-mm level in position and 2-mm/ yr level in velocity. A comparison of 1993 and 1998 coordinates shows that residual velocities of the GPS marks are generally smaller than 2 mm/yr, precluding a detailed tectonic interpretation of the differential motions. However, these data seem to suggest that the N-S compression of the Western Alps is quite mild (less than 2 mm/yr) compared to the global convergence between the African and Eurasian plate (6 mm/yr). This implies that the shortening must be accomodated elsewhere by the deformation of the Maghrebids and/ or by rotations of Mediterranean microplates. Also, E-W velocity components analysis supports the idea that E-W extension exists, as already suggested by recent structural and seismotectonic data interpretation.

The kinematics of the present-day deformation in the western Alps is still poorly known, mostly because of a lack of direct measurements of block motion and internal deformation. Geodetic measurements have the potential to provide quantitative estimates of crustal strain and block motion in the Alps, but the low expected rates, close to the accuracy of the geodetic techniques, make such measurements challenging. Indeed, an analysis of 2.5 years of continuous GPS data at Torino (Italy), Grasse (France), and Zimmerwald (Switzerland), showed that the present-day differential motion across the western Alps does not exceed 3 mm/yr [Calais, 1999]. Continuous measurements performed at permanent GPS stations provide unique data sets for rigorously assessing crustal deformation in regions of low strain rates by reducing the amount of time necessary to detect a significant strain signal, minimizing systematic errors, providing continuous position time series, and possibly capturing co- and post-seismic motion. In 1997, we started the implementation of a network of permanent GPS stations in the western Alps and their surroundings (REGAL network). The REGAL network mostly operates dual frequency Ashtech Z12 CGRS GPS stations with choke-ring antennae. In most cases, the GPS antenna is installed on top of a 1.5 to 2.5 m high concrete pilar directly anchored into the bedrock. The data are currently downloaded once daily and sent to a data center located at Geosciences Azur, Sophia Antipolis where they are converted into RINEX format, quality checked, archived, and made available to users. Data are freely available in raw and RINEX format at http://kreiz.unice.fr/regal/. The GPS data from the REGAL network are routinely processed with the GAMIT software, together with 10 global IGS stations (KOSG, WZTR, NOTO, MATE, GRAZ, EBRE, VILL, CAGL, MEDI, UPAD) that serve as ties with the ITRF97. We also include the stations ZIMM, TORI, GRAS, TOUL, GENO, HFLK, OBER because of their tectonic interest. We obtain long term repeatabilities on the order of 2-3 mm for the horizontal components, 8-10 mm for the vertical component. Using a noise model that combines white and coloured noise (flicker noise, spectral index 1), we find uncertainties on the velocities ranging from 1 mm/yr for the oldest stations (ZIMM, GRAS, TOUL, TORI, SJDV) to 4-5 mm/yr for the most recently installed (CHAT, MTPL). Station velocities obtained in ITRF97 are rotated into a Eurasian reference by substracting the rigid rotation computed from ITRF97 velocities at 11 central European sites located away from major active tectonic structures (GOPE, JOZE, BOR1, LAMA, ZWEN, POTS, WETT, GRAZ, PENC, Effelsberg, ONSA). The resulting velocity field shows residual motions with respect to Eurasia lower than 3 mm/yr. We obtain at TORI, in the Po plain, a residual velocity of 2.3+ or -0.8 mm/yr to the SSW and a velocity of 1.9+ or -1.1 mm/yr at SJDV, on the Alpine foreland. These results indicate that the current kinematic boundary conditions across the western Alps are extensional, as also shown by the SJDV-TORI baseline time series. We obtain at MODA (internal zones) a residual velocity of 1.2+ or -1.2 mm/yr to the SSE. The MODA-FCLZ baseline show lengthening at a rate of 1.6+ or -0.8 mm/yr. These results are still marginally significant but suggest that the current deformation regime along the Lyon-Torino transect is extension, as also indicated by from recent seismotectonic data. It is in qualitative agreement with local geodetic measurements in the internal zones (Briancon area) but excludes more than 2.4 mm/yr of extension (FCLZ-MODA baseline, upper uncertainty limit at 95% confidence). Our results indicate a different tectonic regime in the southern part of the western Alps and Provence, with NW-SE to N-S compression. The GRAS-TORI baseline, for instance, shows shortening at a rate of 1.4+ or -1.0 mm/an. This result is consistent with seismotectonic data and local geodetic measurements in these areas. The Middle Durance fault zone, one of the main active faults in this area, is crossed by the GINA-MICH baseline, which shows shortening at a rate of 1.0+ or -0.8 mm/an. This result is only marginally significant, but confirms the upper bound of 2 mm/yr obtained from triangulation-GPS comparisons. The REGAL permanent GPS network has been operating since the end of 1997 for the oldest stations and will continue to be densified. Although they are still close to or within their associated uncertainties, preliminary results provide, for the first time, a direct estimate of crustal deformation across and within the western Alps.

The REGAL permanent GPS network currently consists of 12 GPS stations covering the Western Alps and their foreland. Preliminary results indicate ( i ) residual velocities with respect to Eurasia lower than 3 mm·yr –1 , ( ii ) extensional kinematic boundary conditions along the Lyons–Turin transect and extensional strain regime in the central part of the Western Alps, and ( iii ) north–south to NW–SE compression in the southern Alps and Provence. These results are still preliminary and marginally significant, given the associated uncertainties. They are however consistent with the most recent seismotectonic results published in these areas.

Two new gravity surveys performed in the western Alps allow the drawing of a high-resolution gravity map. Moreover, a well-constrained Moho depth model was used to correct the initial map from the Moho depth variation gravity effect and to interpret the residual effect in terms of crustal heterogeneities. The main structures of the western Alps are pointed out, specially the Ivrea body parallel to the Penninic front, the crystalline massifs (Simplon-Tessin, Pelvoux, Mercantour) and the sedimentary basins and nappes of the southern Alps (Digne, Castellane, Valensole).

Com o objetivo de analisar, na amostra, fatores que influenciaram a morbidade pós-operatória após trauma hepático penetrante, realizou-se um estudo prospectivo com 61 pacientes submetidos a cirurgia por trauma hepático penetrante no Hospital de Pronto Socorro (HPS) durante 12 meses. Foram excluídos os óbitos ocorridos nas primeiras 24 horas após o trauma. As seguintes variáveis foram estudadas: idade, mecanismo de trauma, choque, grau de lesão hepática, lesões intra- abdominais associadas, técnica cirúrgica e drenagem peri-hepática. Utilizou-se um modelo de regressão logística múltipla para avaliar a correlação entre esses fatores e a ocorrência de complicações pós-operatórias. A média de idade foi de 26± 3,49 anos, variando entre 17 e 63 anos. Trauma por arma de fogo ocorreu em 34 casos (55,7%) e por arma branca em 27 (44,3%). O choque esteve presente em 37 casos (60,7%). As lesões hepáticas de grau II e III (42,6% e 41 %) foram as mais comuns, e as lesões intra-abdominais associadas mais freqüentes foram de estômago (18 casos - 29,5% ) e cólon (nove casos - 14,7% ). O ATI médio foi 20,5 ±17. As complicações pós-operatórias mais comuns foram broncopneumonia (dez casos - 25%) e abscesso intra-abdominal (seis casos - 9,8%). Houve dois óbitos na série. Foram fatores preditivos de complicações, nessa amostra, o choque, os ferimentos por projetis de arma de fogo e a complexidade da cirurgia hepática. This study is a prospective analysis of 61 patients who suffered penetrating hepatic trauma followed by surgery, and the aspects that influenced the post-surgical morbidity. The study was developed during 12 months at Hospital de Pronto Socorro de Porto Alegre, RS, Brazil, and did not consider the deaths which occurred along the first 24 hours after the trauma. The following aspects were studied: age, trauma mechanism, shock, hepatic lesion grade, associated intra-abdominal lesions, surgical technique and peri-hepatic drainage. We employed a multiple logistic regression model to evaluate the relationship between these events and the occurrence of post-surgical morbidity. The average age was 26:1: 3.49, varying from 17 to 63 years. Gunshot wounds occurred in 34 cases (55.7%) and stab wound in 27 cases (44.3%). Shock was present in 37 cases (60.7%). Grade I and II hepatic lesions (42.6% and 41% respectively) were the most frequent while the most commonly associated intra-abdominal lesions were those of stomach (18 cases/29.5%) and colon (9 cases/14.7%). The average ATI was 20.5 ± 17. Pneumonia (10 cases/25%) and intra-abdominal abscess (6 cases/9,8%) were the most frequent post-surgical complications. The series presented two deaths. Shock, gunshot wounds and the complexity of the surgical procedure were considered to be predictive factors of morbidity.

Analysis of seismic lines coupled with gravity interpretation in the western Gulf of Oman, shows that the rootless Cretaceous ophiolite nappes are bounded to the north by the deep arcuate Sohar Basin. Two phases of sedimentary infill are clearly identified; from late Campanian to Miocene and from Miocene to Quaternary. The Sohar Basin is separated from the oceanic domain by a continental axis interpreted as the NW seaward prolongation of the Saih-Hatat metamorphic unit. We assume that creation of the Sohar Basin resulted from a late-obduction uplift of the Saih-Hatat axis followed by the re-working of the basal thrust during a later Neogene compressive event.

Precise estimation of the vertical deformation is a challenge for understanding geodynamical processes. In mountainous areas, the main limitation of precise GPS vertical measurement lies in the difficulty of estimating tropospheric delay due to high differential elevation and large weather variability. We carried out two GPS campaigns in July 1994 (8 days) and March 1996 (11 days), during extreme weather conditions, on a 1 390 m height difference baseline. The zenith delay was calibrated with a standard atmospheric model (STD), Water Vapor Radiometric measurements (WVR) and surface pressure measurements, or computed through a least squares estimation (LSE). Half daily repeatability of the vertical LSE solutions has a precision of 11–14 mm with a small difference of 1 mm between the two expeditions.

The obduction process in Oman during Late Cretaceous time, and continental-to-oceanic subduction along the Zagros-Makran region during the Tertiary are consequences of the Arabian-Eurasian collision, resulting in construction of complex structures composed of the Oman ophiolite belt, the Zagros continental mountain belt and the Makran subduction zone with its associated accretionary wedge. In this paper, we jointly interpret Bouguer anomaly and available petroleum seismic profiles in terms of crustal structures. We show that the gravity anomaly in northern Oman is characterized by a high-amplitude negative-positive couple. The negative anomaly is coincident with Late Cretaceous (Fiqa) and Tertiary (Pabdeh) foreland basins and with the Zagros-Oman mountain belts, whereas the positive anomaly is correlated to the ophiolite massifs. The Bouguer anomaly map indicates the presence of a post-Late Cretaceous sedimentary basin, the Sohar basin, centred north of the Batinah plain. We interpret the negative/positive couple in terms of loading of the elastic Arabian lithosphere. We estimate the different Cretaceous-to-Recent loads, including topography, ophiolite nappes, sedimentary fill and the accretionary prism of the Makran trench. A new method, using Mindlin's elastic plate theory, is proposed to model the 2D deflection of the heterogeneous elastic Arabian plate, taking into account boundary conditions at the ends of the subducted plate. We show that remnant ophiolites are isolated from Tethyan oceanic lithosphere in the Gulf of Oman by a continental basement ridge, a NW prolongation of the Saih-Hatat window. Loading the northward-limited ophiolite blocks explains the deflection of the Fiqa foredeep basin. West of the Musandam Peninsula, the Tertiary Pabdeh foredeep is probably related to the emplacement of a 8-km-thick tectonic prism located on the Musandam Peninsula and in the Strait of Hormuz. Final 2D density models along profiles through the Oman mountain belt and the Gulf of Oman are discussed in the framework of Late Cretaceous obduction of the Tethys and synchronous subduction and exhumation of the Oman margin.

The 8th International Comparison of Absolute Gravimeters (ICAG2009) took place at the headquarters of the International Bureau of Weights and Measures (BIPM) from September to October 2009. It was the first ICAG organized as a key comparison in the framework of the CIPM Mutual Recognition Arrangement of the International Committee for Weights and Measures (CIPM MRA) (CIPM 1999). ICAG2009 was composed of a Key Comparison (KC) as defined by the CIPM MRA, organized by the Consultative Committee for Mass and Related Quantities (CCM) and designated as CCM.G-K1. Participating gravimeters and their operators came from national metrology institutes (NMIs) or their designated institutes (DIs) as defined by the CIPM MRA. A Pilot Study (PS) was run in parallel in order to include gravimeters and their operators from other institutes which, while not signatories of the CIPM MRA, nevertheless play important roles in international gravimetry measurements. The aim of the CIPM MRA is to have international acceptance of the measurement capabilities of the participating institutes in various fields of metrology. The results of CCM.G-K1 thus constitute an accurate and consistent gravity reference traceable to the SI (International System of Units), which can be used as the global basis for geodetic, geophysical and metrological observations of gravity. The measurements performed afterwards by the KC participants can be referred to the international metrological reference, i.e. they are SI-traceable. The ICAG2009 was complemented by a number of associated measurements: the Relative Gravity Campaign (RGC2009), high-precision levelling and an accurate gravity survey in support of the BIPM watt balance project. The major measurements took place at the BIPM between July and October 2009. Altogether 24 institutes with 22 absolute gravimeters (one of the 22 AGs was ultimately withdrawn) and nine relative gravimeters participated in the ICAG/RGC campaign. This paper is focused on the absolute gravity campaign. We review the history of the ICAGs and present the organization, data processing and the final results of the ICAG2009. After almost thirty years of hosting eight successive ICAGs, the CIPM decided to transfer the responsibility for piloting the future ICAGs to NMIs, although maintaining a supervisory role through its Consultative Committee for Mass and Related Quantities. © 2012 BIPM & IOP Publishing Ltd.

The southern Rhine Graben was investigated by the seismic reflection ecors-dekorp program. Gravity data available in this region have been reprocessed in order to develop a coherent map along the seismic line. The new map has been corrected for the gravity effects of tertiary sediment and crust-mantle discontinuity. The strong negative gradient towards the Alps may be explained by a density contrast of 300–500 kg/m3 at the crust-mantle interface. The residual map shows a negative, long-wavelength anomaly superimposed on the Moldanubian domain of the Variscan belt, along a Vosges-Black Forest-Swabian Jura axis. This anomaly cannot be explained by the properties of the Variscan crust but may result from a low-density body within the upper mantle. However, its ENE-WSW direction rules out any connection with the formation of the Tertiary grabens, which trend north-south. The recent uplift of topography and the volcanic activity (< 20 Ma) of the southern Rhine Graben may partly be a consequence of an asthenospheric upwelling beneath this area. The analysis of the residual short-wavelength anomalies shows a fundamental difference between the light Variscan terranes of the Moldanubian zone and the dense “Barrandian” Saverne-Kraighau structures of the Saxothuringian domain. A density cross-section along the ecors-dekorp line confirms that the Moho uplift extends beyond the Graben, whereas thinning of the lower crust affects the Graben area only. We interpret this crustal structure as an initially thin Hercynian crust, later deformed by asymmetric extension during Oligocene rifting.

[1] The aim of this study is to bring new information on water storage dynamics in karst systems from tiltmeter measurements. Newly developed long-base hydrostatic tiltmeters are installed at two sites on the Larzac plateau (France) in a karst aquifer of ∼100 km2 recharge area. Each site is located within a karst cave where two tilt directions are monitored. Significant reversible tilt deformation reaching amplitudes of 10−6 to 10−5 rad was observed at both sites following heavy precipitation. Elastic parameters were determined with an experiment in which a tiltmeter site was loaded by up to 25 t of weight at strategic locations at the ground surface. Mechanisms responsible for the observed tilt were then examined by means of finite element modeling. Deformation induced by water pressure changes in fractures is our preferred interpretation as the most plausible mechanism. Within this scope, we used the tiltmeter responses to extract time constants using lumped parameter modeling. Time constants are interpreted to be associated with the filling and emptying of fractures nearby the tiltmeters. These instruments therefore appear as useful tools to study the local dynamics of water infiltration in karst systems.

International audience; South-east Iran is the site of a rare case of young transition between subduction and collision. We synthesized recent results in geodesy, tectonics, seismology and magnetism to understand the structure and kinematics of the Zagros-Makran transition. Surface observations (tectonics, magnetism and geodesy) draw a transpressive discontinuity consisting of several faults striking obliquely to the convergent plate motion, whereas deeper observations (seismology) support a smooth transition across the fault system. No lithospheric transform fault has been created, even though the transition already behaves like a major boundary in terms of tectonic style, seismic structure, lithology and magnetism. The Zendan-Minab-Palami fault system consists of several faults that accommodate a transpressive tectonic regime. It is the surface expression of a southward propagation of the N-trending right-lateral strike-slip fault system of Jiroft-Sabzevaran. Within each system the numerous faults will coalesce into a single, lithospheric, wrench fault.

The International Comparison of Absolute Gravimeters ICAG-2005 was held at the Bureau International des Poids et Mesures (BIPM), Sevres, France in September 2005. The organization of ICAG-2005, measurement strategy, calculation and presentation of the results were described in a technical protocol pre-developed to the comparison. Nineteen absolute gravimeters carried out 96 series of measurements of free-fall acceleration g at the sites of the BIPM gravity network. The vertical gravity gradients were measured by relative gravimeters. For the first time the budgets of uncertainties were presented.

The second international comparison of absolute gravimeters was held in Walferdange, Grand Duchy of Luxembourg, in November 2007, in which twenty absolute gravimeters took part. A short description of the data processing and adjustments will be presented here and will be followed by the presentation of the results. Two different methods were applied to estimate the relative offsets between the gravimeters. We show that the results are equivalent as the uncertainties of both adjustments overlap. The absolute gravity meters agree with one another with a standard deviation of 2 μgal (1 gal = 1 cm/s2).

International audience; P>The Strait of Hormuz area is a transition zone between the continental collision of the Zagros (west) and the subduction of an oceanic part of the Arabian Plate beneath the Makran wedge (east). Geology and recent GPS measurements indicate that about 15 mm yr-1 of relative motion in N10 degrees E direction is accommodated by two major fault systems: (1) the NNW-trending Minab-Zendan-Palami (MZP) fault system that connects the Main Zagros Thrust (MZT) to the inner Makran thrust system and the Frontal subduction thrust and (2) the N-trending Sabzevaran-Kahnuj-Jiroft (SKJ) fault system that bounds the Jazmurian depression to the west. We use dense GPS measurements along four transects across these fault systems in order to determine the strains spatial distribution. The northern GPS transect confirms the total fault slip rates for both fault systems estimated by the tectonic analyses (about 10 and 7.3 mm yr-1 in N10 degrees direction across the MZP and SKJ fault systems, respectively). For both fault systems, the elastic deformation spreads over shear zones that are several tens of kilometres wide. However, transects located close to latitude 27 degrees N reveal a much narrower shear zone (similar to 10 km) for the MZP fault system. Moreover, we confirm that most of the present-day strain is transferred towards the frontal subduction thrust rather than towards the inner Makran thrusts. In order to complement this new GPS velocity field with spatially dense measurements, we processed a set of ERS radar images by the radar interferometry (InSAR) technique. We used both a 'stacking' and a 'persistant-scatterers' approach to differentiate the ground deformation signal which spatial gradient is expected to be very low, from the atmospheric signal. Results from these interferograms appear to be relatively in agreement with the GPS-determined strain distribution. Nevertheless, they confirm the absence of any superficial creep behaviour since no sharp discontinuity on interferometric phase can be noted on any interferogram. Finally, we use a purely kinematic 'block model' inversion process to calculate slip rates and locking depths for each fault system from our GPS measurements. These models suggest that the relative quiescence over the last 200 yr has certainly produced a slip deficit as high as 2 m. So, we may wonder if the MZP fault system is not late in the interseismic phase of its earthquake cycle.

International audience; This paper is the first presentation of a project called GHYRAF (Gravity and Hydrology in Africa) devoted to the detailed comparison between models and multidisciplinary observations (ground and satellite gravity, geodesy, hydrology, meteorology) of the variations of water storage in Africa from the Sahara arid part to the monsoon equatorial part. We describe the various actions planned in this project. We first detail the actions planned in gravimetry which consist in two main surface gravity experiments: on the one hand the periodic repetition of absolute gravity measurements along a north-south monsoonal gradient of rainfall in West Africa, going from Tamanrasset (20 mm/year) in southern Algeria to Djougou (1200 mm/year) in central Benin; on the other hand the continuous measurements at Djougou (Benin) with a superconducting gravimeter to monitor with a higher sampling rate the gravity changes related to an extreme hydrological cycle. Another section describes the actions planned in GPS which will maintain and develop the present-day existing network in West Africa. The third type of actions deals with hydrol-ogy and we review the three sites that will be investigated in this joint hydrogeophysics project namely Wankama (near Niamey) and Bagara (near Diffa) in the Niger Sahelian zone and Nalohou (near Djougou) in the Benin monsoon zone. We also address the question of the ground truth of satellite-derived missions ; in this context the GHYRAF project will lead to test the hydrology models by comparison both with in situ and satellite data such as GRACE, as well as to an important increase of our knowledge of the seasonal water cycle in Africa. We finally present preliminary results in GPS based on the analysis of the vertical motion of the Djougou site. The resulting absolute gravity changes related to the 2008 monsoon are finally given.

International audience; The island of Taiwan is located on the convergent boundary between the Philippine Sea plate and the Chinese continental margin. It offers very active mountain building and collapsing processes well illustrated by the rugged topography, rapid uplift and denudation, young tectonic landforms, active faulting and numerous earthquakes. In this paper, using simple models, we have estimated vertical movements and associated absolute gravity variations which can be expected along a profile crossing the southern part of the island and probably suffering the highest rates of rising. The two different tectonic styles proposed for the island, thin-skinned and thick-skinned, were taken into account. Horizontal and vertical movements were modeled by an elastic deformation code. Gravity variations due to these deformations are then modeled at a second step. They are dominated by plate and free-air effects, i.e. elevation of the topography, with several mu Gal yr(-1). By comparison, gravity changes generated by mass transfers are weak: maximum 0.1 mu Gal yr(-1) with the thin-skinned tectonic and 0.3 mu Gal yr(-1) with the thick-skinned tectonic. Though elastic rheology has limitations, this modeling offers interesting results on what gravity signal can be expected from the AGTO project (Absolute Gravity in the Taiwanese Orogen), which proposes to study the dynamic of these mountain ranges using absolute gravimetry (AG) and also including relative gravimetry (RG) and GPS measurements.

TAG LITHO; In this study we attempt to understand the water storage variations in a karst aquifer on the Larzac Plateau (South of France) using absolute gravimetry. On this karst system, water input is exclusively rainfall and draining occurs at the Durzon perennial spring in a karstic valley. Our basis assumption is that water storage in the vadose zone (epikarst and infiltration zone) has a significant effect on surface gravity through Newtonian attraction. The karst aquifer is hence being monitored since January 2006 with monthly absolute gravity measurements at three sites. The gravity measurements are corrected for regional scale gravity using water storage models in order to obtain gravity variations related exclusively to the local water storage variations. The gravity variations exhibit an important seasonal component (10-15 mu gal corresponding to a variation of equivalent water stab thickness of similar to 24-36 cm). Water storage variation seen by gravimetry is not spatially uniform on the studied karst system, corroborating current geomorphologic observations and interpretations. Finally, we use a global mass balance consideration linking rainfall, evapotranspiration and spring discharge to provide a conceptual framework for the understanding of observed gravity variations.

International audience; The Bandar Abbas-Strait of Hormuz zone is considered as a transition between the Zagros collision and the Makran oceanic subduction. We used GPS network measurements collected in 2000 and 2002 to better understand the distribution of the deformation between the collision zone and the Makran subduction. Analysing the GPS velocities, we show that transfer of the deformation is mainly accommodated along the NNW-SSE-trending reverse right-lateral Zendan-Minab-Palami (ZMP) fault system. The rate is estimated to 10 +/- 3 mm yr-1 near the faults. Assuming that the ZMP fault system transfers the motion between the Makran-Lut Block and the Arabian plate, we estimate to 15 mm yr-1 and 6 mm yr-1, respectively, the dextral strike-slip and shortening components of the long-term transpressive displacement. Our geodetic measurements suggest also a 10-15 km locking depth for the ZMP fault system. The radial velocity pattern and the orientation of compressive strain axes around the straight of Hormuz is probably the consequence of the subducting Musandam promontory. The N-S Jiroft-Sabzevaran (JS) fault system prolongates southwards the dextral shear motion of the Nayband-Gowk (NG) fault system at an apparent rate of 3.1 +/- 2.5 mm yr-1. The change from strong to weak coupling for underthrusting the Arabian plate beneath the Zagros (strong) and the Makran (weak) may explain the dextral motion along the ZMP, JS/NG and Neh-Zahedan fault systems which transfer the convergence from a broad zone in the western Iran (Zagros, Tabriz fault system, Alborz, Caucasus and Caspian sea surroundings) to Makran subduction.

Geophysical Journal International, 152 (1), ISSN:0956-540X, ISSN:1365-246X

A high-precision GPS network was installed in the Western Alps in September 1993 to map the movement of the African and Eurasian plates in the Mediterranean region. The GPS measurements will explain how convergence is distributed in the Western Alps, the largest, highest, and most deformed range in the Alpine collision zone. If a large earthquake strikes the region, the network will also help constrain the dislocation at depth. Measurements of convergence will be made every five years. Global plate motion models predict a north-south mean convergence rate of 6 mm/yr between the African and Eurasian plates in the Western Mediterranean region (Figure lb). Most of this deformation is probably accommodated in the active mountain belts: the Pyrenees, Alps, Apennines, and Maghrebids. Deformation in these structures is complex.

We present an inverse method for processing rough data from oil wells in order to evaluate the heat flow density. Assuming that the evaluations of temperatures and thermal resistivities present gaussian uncertainties, we give formulas for computing the optimal value of the heat flow density and its standard deviation. A synthetic example, using likely assumptions on various uncertainties, leads to the prediction that a standard deviation of about 10 mW m−2 could apply to heat flow estimates from oil well data for typical situations.

We investigate in this paper the possible origin of the high heat flow anomaly observed in the Massif Central (100–110 mW m−2). A detailed study of crustal heat production shows that the radioactive component cannot account for the entire surface anomaly. However, when we remove the integrated radioactive contribution from the surface heat flow, it appears that the anomaly is reduced to a smaller area close to the Cenozoic graben and the volcanic area, with an amplitude of 25–30 mW m−2. This mantle heat flow anomaly is interpreted as a transient component related to a mantle diapir ascent in the Massif Central since the Oligocene, also outlined by several other geological and geophysical studies. A kinematic model of thermal diapir in the mantle can explain this transient anomaly as well as other independent sets of data (gravity anomaly, topography, lithospheric thickness, partial melting) provided the vertical velocity of the ascent is 1 cm yr−1, the width of the diapir 40 km and the depth where it initiates 150 km.

In order to furnish further constraints to modelling the ECORS Pyrenees deep seismic profile, gravity data were collected along a stripe 20 km wide and 220 km long containing the seismic line. A total of 4020 stations have been used to derive a Bouguer anomaly map of the area, A large and roughly symmetrical negative anomaly ( - 100 mGa1) is centered on the Axial zone. A local positive anomaly over the North Pyrenean zone disturbs the negative regional trend. Somewhat detailed densities were assigned to the sedimentary cover on tbe basis of borehole samples. Refraction data and a velocity-density relationship were used to constrain the densities adopted for the deeper layers. The results of the two-dimensional gravity modelling confirm the asymmetrical shape of the crust/mantle boundary beneath the Pyrenean belt; the downward deflection of the Iberian Moho from the Ebro basin leads to a maximum depth of 65 km under the Paleozoic Axial zone, whereas a depth of 35 km is found for the European Moho under the North Pyrenean zone. Two extreme models are proposed for the northern limit of the Iberian crust, a vertical contact in the downward continuity of the North Pyrenean fault or a 70° northward-sloping interface. The positive anomalies beneath the North Pyrenean zone may be explained by dense intractustal mantle slices or lower crustal sheets. The outcrop of granulitic basic gneiss within the Labourd massif suggests that the anomaly results from lower crustal sheets.

A package of Fortran routines using linear programming techniques in linear inverse problems as gravimetry or geomagnetism is presented. These routines, with a complete description and examples of their applications, are available at the SEG Business Office. This paper presents a brief description of the package and the general features of the method; taking into account the nonuniqueness of the solution, the bounds of some parameters or some particular solutions, such as the “ideal body” [Parker (1975)], are computed. This package can be applied to inverse gravity or geomagnetic problems with a maximum data size on IBM 360/65 of the order such that the number of measurements ⩽ 250, number of unknowns ⩽ 600.

In Iceland tectonic activity in the neovolcanic zone leads to the formation of three kinds of parallel structures: open fissures, emissive fissures, and normal faults. This observation is used to built a kinematic model which is based on the superposition of lava flows generated from an active central belt of finite width. The results are in good agreement with the recent results in magnetism and tectonic observations of both subaerial and underwater active ridges.

The aim of this paper is to use linear inverse theory to interpret gravity surveys in mining exploration by incorporating a priori information on the densities and data in terms of Gaussian or uniform probability laws. The Bayesian approach and linear programming techniques lead to the solution of well‐posed questions resulting from the exploration process. In particular, we develop a method of measuring the possible heterogeneity within a given domain by using linear programming. These techniques are applied to gravity data taken over the massive sulfide deposit of Neves Corvo (Portugal). We show how crude constraints on the densities lead to a first estimation of the location of sources, while further geologic constraints allow us to estimate the heterogeneity and to put definite bounds on the ore masses.