Physiologie du protecteur (2e édition) / par un aveugle clairvoyant de la Chaussée-d'Antin [Jacques Arago]...

Référence bibliographique : Lhéritier, 24

Formation of chlorite during thrust fault reactivation. Record of fluid origin and P-T conditions in the Monte Perdido thrust fault (southern Pyrenees)

The chemical and isotopic compositions of clay minerals such as illite and chlorite are commonly used to quantify diagenetic and low-grade metamorphic conditions, an approach that is also used in the present study of the Monte Perdido thrust fault from the South Pyrenean fold-and-thrust belt. The Monte Perdido thrust fault is a shallow thrust juxtaposing upper Cretaceous-Paleocene platform carbonates and Lower Eocene marls and turbidites from the Jaca basin. The core zone of the fault, about 6 m thick, consists of intensely deformed clay-bearing rocks bounded by major shear surfaces. Illite and chlorite are the main hydrous minerals in the fault zone. Illite is oriented along cleavage planes while chlorite formed along shear veins (< 50 mu m in thickness). Authigenic chlorite provides essential information about the origin of fluids and their temperature. delta O-18 and delta D values of newly formed chlorite support equilibration with sedimentary interstitial water, directly derived from the local hanging wall and footwall during deformation. Given the absence of large-scale fluid flow, the mineralization observed in the thrust faults records the P-T conditions of thrust activity. Temperatures of chlorite formation of about 240A degrees C are obtained via two independent methods: chlorite compositional thermometers and oxygen isotope fractionation between cogenetic chlorite and quartz. Burial depth conditions of 7 km are determined for the Monte Perdido thrust reactivation, coupling calculated temperature and fluid inclusion isochores. The present study demonstrates that both isotopic and thermodynamic methods applied to clay minerals formed in thrust fault are useful to help constrain diagenetic and low-grade metamorphic conditions.

On high-rate full-diversity 2x2 space-time codes with low-complexity optimum detection

The 2×2 MIMO profiles included in Mobile WiMAX specifications are Alamouti’s space-time code (STC) fortransmit diversity and spatial multiplexing (SM). The former hasfull diversity and the latter has full rate, but neither of them hasboth of these desired features. An alternative 2×2 STC, which is both full rate and full diversity, is the Golden code. It is the best known 2×2 STC, but it has a high decoding complexity. Recently, the attention was turned to the decoder complexity, this issue wasincluded in the STC design criteria, and different STCs wereproposed. In this paper, we first present a full-rate full-diversity2×2 STC design leading to substantially lower complexity ofthe optimum detector compared to the Golden code with only a slight performance loss. We provide the general optimized form of this STC and show that this scheme achieves the diversitymultiplexing frontier for square QAM signal constellations. Then, we present a variant of the proposed STC, which provides a further decrease in the detection complexity with a rate reduction of 25% and show that this provides an interesting trade-off between the Alamouti scheme and SM.

A comparison of full-rate full-diversity 2x2 space-time codes for WiMAX systems

Multiple-input multiple-output (MIMO) techniques have become an essential part of broadband wireless communications systems. For example, the recently developed IEEE 802.16e specifications for broadband wireless access include three MIMOprofiles employing 2×2 space-time codes (STCs), and two of these MIMO schemes are mandatory on the downlink of Mobile WiMAX systems. One of these has full rate, and the other has full diversity, but neither of them has both of the desired features. The third profile, namely, Matrix C, which is not mandatory, is both a full rate and a full diversity code, but it has a high decoder complexity. Recently, the attention was turned to the decodercomplexity issue and including this in the design criteria, several full-rate STCs were proposed as alternatives to Matrix C. In this paper, we review these different alternatives and compare them to Matrix C in terms of performances and the correspondingreceiver complexities.

Tartrate-Resistant Acid Phosphatase 5b: a Serum Marker of Bone Resorption

Bone is a physiologically dynamic tissue being constantly regenerated throughout life as a consequence of bone turnover by bone-resorbing osteoclasts and bone-forming osteoblasts. In certain bone diseases, such as osteoporosis, the imbalance in bone turnover leads to bone loss and increased fracture risk. Measurement of bone mineral density (BMD) predicts the risk of fracture, but also biochemical markers of bone metabolism have been suggested to be suitable for prediction of fractures and monitoring the efficacy of antiresorptive treatment. Tartrate-resistant acid phosphatase 5b (TRACP 5b) is an enzyme released from osteoclasts into the circulation, from where it can be detected kinetically or immunologically. Conventional assays for serum total TRACP were spectrophotometric and suffered from interference by other acid phosphatases and non-osteoclastic TRACP 5a isoform. Our aim was to develop novel immunoassays for osteoclastic TRACP 5b. Serum TRACP 5b levels were elevated in individuals with high bone turnover, such as children, postmenopausal women, patients with osteoporosis, Paget’s disease and breast cancer patients with bone metastases. As expected, hormone replacement therapy (HRT) in postmenopausal women decreased the levels of serum TRACP 5b. Surprisingly, the highest TRACP 5b levels were observed in individuals with rare autosomal dominant osteopetrosis type II (ADO2), which is characterized by high BMD and fracture risk with simultaneously elevated levels of deficient osteoclasts. In ADO2 patients, elevated levels of serum TRACP 5b were associated with high fracture frequency. It is likely that serum TRACP 5b reflects the number of inactive osteoclasts in ADO2. Similar results supporting the hypothesis that TRACP 5b would reflect the number of osteoclasts instead of their activity were observed with cultured osteoclasts and in animal models. Novel TRACP 5b immunoassays may prove to be of value either as independent or combinatory tools with other bone metabolic markers and BMD measurements in clinical practice and bone research.

Ryhmämuotoinen kuntoutusjakso sotainvalidien puolisoille ja leskille Kaunialan sotavammasairaalassa

Opinnäytetyön tarkoituksena oli kartoittaa Kaunialan sotavammasairaalan ryhmämuotoiselle kuntoutusjaksolle osallistuneiden kuntoutujien kokemuksia kuntoutusjakson sisällöstä sekä sen merkityksestä psykososiaaliseen- ja fyysiseen toimintakykyyn. Tutkimuksen kohderyhmänä olivat sotainvalidien puolisot ja lesket. Kyseessä on pilottikuntoutusjakso ja se on kertaluontoinen. Tässä työssä on painotettu psykososiaalista näkökulmaa merkittävänä kuntoutuksen toimintakykyä edistävänä tekijänä. Kysely toteutettiin postikyselynä puolistrukturoidulla kyselylomakkeella. Tutkimustapa oli kuvaileva kartoitustutkimus, jossa oli sekä kvalitatiivisia että kvantitatiivisia piirteitä. Tutkimukseen osallistui 29 henkilöä, joista 24 oli leskiä. Tutkimusaineisto kerättiin keväällä 2006. Kvantitatiivinen aineisto analysoitiin SPSS-tilasto-ohjelmistolla ja kvalitatiivisen aineiston analysoinnissa sovellettiin sisällön analyysia. Tutkimuksen tulosten mukaan kuntoutusasiakkaat olivat pääsääntöisesti tyytyväisiä kuntoutusjakson sisältöön. Mielialaan, ihmissuhteisiin ja leskeyteen sekä kuolemaan liittyviä asioita olisi toivottu käsiteltävän enemmän. Ystävällinen henkilökunta ja osaston positiivinen ilmapiiri koettiin tärkeänä osana kuntoutusjaksoa. Ohjatun toiminnan merkitys nousi vastauksista esiin tärkeänä tekijänä arvioitaessa tyytyväisyyttä kuntoutusjakson antiin. Ryhmämuotoisuuden koettiin edistävän kuntoutujien psykososiaalista toimintakykyä. Kuntoutusjakso toimi fyysistä toimintakykyä ylläpitävänä ja edistävänä tekijänä sekä tuki itsenäistä kotona selviytymistä.