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The dispersal of Crocodylus from Africa to Europe during the Miocene is not well understood. A small collection of cranial fragments and postcranial elements from the latest Miocene (6.2 Ma) site of Venta del Moro (Valencia, Spain) have previously been referred to Crocodylus cf. C. checchiai Maccagno, 1947 without accompanying descriptions. Here we describe and figure for the first time the crocodylian remains from Venta del Moro, which represent at least two individuals. Our comparisons indicate that this material clearly does not belong to Diplocynodon or Tomistoma—the only two other crocodylians described so far for the European late Miocene. The material is only tentatively referred to cf. Crocodylus sp. because the apomorphies of this genus are not preserved and a referral to C. checchiai cannot be supported on a morphological basis. However, it is likely that this late Miocene species, originally described from Libya (As Sahabi) and later identified also in Kenya, could have dispersed across the Mediterranean Basin multiple times and colonized the southern areas of Mediterranean Europe, as evidenced by several Crocodylus or Crocodylus-like remains described during the past years.
B vitamins involved in one-carbon metabolism have been implicated in the development of inflammation- and angiogenesis-related chronic diseases, such as colorectal cancer (CRC). Yet, the role of one-carbon metabolism in inflammation and angiogenesis among CRC patients remains unclear. The objective of this study was to investigate associations of components of one-carbon metabolism with inflammation and angiogenesis biomarkers among newly diagnosed CRC patients (n 238) in the prospective ColoCare Study, Heidelberg. We cross-sectionally analysed associations between twelve B vitamins and one-carbon metabolites and ten inflammation and angiogenesis biomarkers from pre-surgery serum samples using multivariable linear regression models. We further explored associations among novel biomarkers in these pathways with Spearman partial correlation analyses. We hypothesised that pyridoxal-5’-phosphate (PLP) is inversely associated with inflammatory biomarkers. We observed that PLP was inversely associated with C-reactive protein (CRP) (r –0·33, Plinear < 0·0001), serum amyloid A (SAA) (r –0·23, Plinear = 0·003), IL-6 (r –0·39, Plinear < 0·0001), IL-8 (r –0·20, Plinear = 0·02) and TNFα (r –0·12, Plinear = 0·045). Similar findings were observed for 5-methyl-tetrahydrofolate and CRP (r –0·14), SAA (r –0·14) and TNFα (r –0·15) among CRC patients. Folate catabolite acetyl-para-aminobenzoylglutamic acid (pABG) was positively correlated with IL-6 (r 0·27, Plinear < 0·0001), and pABG was positively correlated with IL-8 (r 0·21, Plinear < 0·0001), indicating higher folate utilisation during inflammation. Our data support the hypothesis of inverse associations between PLP and inflammatory biomarkers among CRC patients. A better understanding of the role and inter-relation of PLP and other one-carbon metabolites with inflammatory processes among colorectal carcinogenesis and prognosis could identify targets for future dietary guidance for CRC patients.
A monitoring study was carried out in Gumara watershed, upper Blue Nile basin, with the objective of evaluating livestock water productivity (LWP) using a life cycle assessment method. Sixty two smallholder farmers were selected for the study implemented between November 2006 and February 2008. Data on crop and livestock production were collected to allow assessment of livestock water productivity. Study sites were situated in three different rainfed mixed crop/livestock farming systems; barley/potato based system (BPS), tef/finger-millet based system (TMS), and rice/noug based system (RNS). LWP was found to be significantly lower (p < 0.01) in RNS (0.057 USD m−3 water) than in TMS (0.066 USD m−3 water) or in BPS (0.066 USD m−3 water). Notably, water requirement per kg live weight of cattle increased towards the lower altitude area (in RNS) mainly because of increased evapo-transpiration. As a result, 20% more water was required per kg live weight of cattle in the low ground RNS compared to BPS situated in the upstream parts of the study area. Cattle herd management that involved early offtake increased LWP by 28% over the practice of late offtake. Crop water productivity expressed in monetary units (0.39 USD m−3 water) was higher than LWP (0.063 USD m−3 water) across the mixed farming systems of Gumara watershed. Strategies for improving LWP, from its present low level, could include keeping only the more productive animals, increasing pasture productivity and linking production to marketing. These strategies would also ease the imbalance between the existing high livestock population and the declining carrying capacity of natural pasture.
Capnography and capnometry provide useful information that may help improve decision-making and reduce complications during transport. This chapter reviews specific clinical applications of capnography and capnometry: assuring proper endotracheal tube placement, monitoring airway circuit integrity, monitoring the consistency of mechanical ventilation, improving safety in procedural sedation, assessing cardiac output, and evaluating patients in cardiac arrest. Capnometry and capnography aid in the confirmation of correct endotracheal tube placement. End-tidal CO2 (ETCO2) measurement can accurately detect esophageal intubation because CO2 is exhaled through the trachea, and not the esophagus. Once an airway device is in place, continuous monitoring is important to assure ventilator circuit patency, including that of the endotracheal tube, and to assure consistent levels of ventilation. Capnography is the gold standard for monitoring patients on airway appliances and ventilator circuits, and there are useful roles for the technology during procedural sedation and evaluating patients in the time surrounding arrest states.
A summer outbreak of severe gastroenteritis followed by haemolytic uraemic syndrome (HUS) and thrombotic thrombocytopenic purpura in a nursery school and kindergarten is described. Sandwiches prepared with green butter made with contaminated parsley were the likely vehicle of infection. The parsley originated from an organic garden in which manure of pig origin was used instead of artificial fertilizers, Cornally identical Verotoxinogenic Citrobacter freundii were found as causative agents of HUS and gastroenteritis and were also detected on the parsley.
Most steel grades undergo a ductility trough in the temperature
range 700 to 1100 °C that may bring about surface cracks in the CC
strands. Micro-mechanical modelling of the as solidified austenite-ferrite
microstructure, supported by experimental evaluations of the fracture
surfaces, affords a comprehensive description of the crack formation
mechanism. This opens the way for a quantitative evaluation
of the sensitivity of CC strands to transverse cracks.
An amorphous silicon photoconductor to detect wavelengths between 180 nm to 550 nm without scintillator is presented. The photoconductor is based on a coplanar configuration of the electrodes, similar to measurement structures to determine material characteristics of amorphous layers, e.g. for the Constant Photocurrent Method (CPM). After passing through a thin transparent passivation layer, the incident radiation is directly absorbed in the intrinsic a-Si:H material. The carrier collecting electrical field is applied perpendicular to the incoming light. Test structures have been fabricated with 80 nm thick sputtered chromium contacts on top of a 60 nm carbonized hydrogenated i-layer and a SixNx passivation layer with a thickness of about 36 nm. The spacing between the Schottky contacts is varied between 3 μm and 100 μm. They are deposited on top or below the a-SiC:H layer. First experiments with this simple coplanar design show that with an increasing voltage a shift towards UV wavelengths can be observed. The new UV detector is applicable in the field of TFA image sensors (Thin Film on ASIC) and in the new Lab-on-a-Chip concept presently under development at the institute for microsystem technologies.
TFA technology, using ASICs coated with amorphous silicon based photo detectors, opens new applications for CMOS image sensors. One particular field of interest is the detection of low light level images with pixel photocurrents in the femtoampere range and below. In this paper we describe the effects of the capacitances on the pixel amplifier, we derive noise values for the detector and the amplifier, and we estimate the gain fixed pattern noise level. An inverter circuit providing a 40-fold increase of the charge conversion gain is presented.
This experiment aimed to investigate the influence of folic acid supplements on the carry-over of folates from the sow to the fetus during late gestation and to the suckling piglet. Two groups of sixteen German Landrace sows received, during gestation and lactation, a diet supplemented with either 0 or 10 mg folic acid/kg. Increased folic acid concentrations in the serum of sows were detected only at the end of gestation (day 100) and at the end of lactation (day 28). The supplementation with folic acid to the sows' diet improved the folic acid supply of the fetus compared with unsupplemented controls; values were respectively 92.6 v. 56.2 nmol folates/l serum in newborn piglets and 171.9 v. 76.3 μmol folates/g fresh liver in stillborn piglets (P < 0.05). Folate concentrations in colostrum and milk (day 28) were 3.6- and 5.0-times higher in supplemented than unsupplemented sows. This treatment effect was also reflected in the serum of piglets until weaning. Therefore, the folic acid supply for the suckling piglet is dependent mainly upon the carry-over of maternal folates via colostrum and milk.
The noise current spectral density of an a-Si:H pin diode can be calculated with experimentally determined flicker noise coefficients by superposition of the shot and flicker noise spectra of photocurrent and dark current. The dependence of the flicker noise current spectral density in pin diodes on the pixel area is calculated with our expansion of Hooge's law for flicker noise. We propose a new method for the calculation of dynamic range (DR) and signal-to-noise ratio (SNR) in pin diode pixels as a function of pixel area, dark current, photocurrent and the integration time of the imager. DR and SNR of the pin diodes are calculated for Thin Film on ASIC (TFA) image sensors.
An image sensor with enhanced sensitivity for near ultraviolet radiation (UVA) has been fabricated in TFA (Thin Film on ASIC) technology. The device employs an amorphous silicon pin detector optimized for UV detection by carbonization and layer thickness variation. The front electrode consists of an Al grid or TCO. Measurements show a peak responsivity of 90 mAW-1 at 380 nm. The UV Imager prototype consists of 128 × 128 pixels with a size of 25 μm × 25 [tim each, fabricated in a 0.7 μm CMOS process. Global sensitivity control serves to achieve a dynamic range in excess of 80 dB. The sensor can be used in fields such as chemical, medical and astronomical applications. Furthermore, a UV monitor has been developed, suited to warn of excessive sunlight exposure, considering skin type and sun protection factor.
This work presents first results of potential manufacturing processes for integrated series connected hydrogenated amorphous silicon (a-Si:H) thin film solar modules and/or pindiode/TFT based macroelectronic circuits on flexible tapes. A RTR (Reel-To-Reel) deposition system on laboratory scale has been built, The system consists of seven metal sealed LIHV stinless steel chambers to obtain ultra high vacuum as a basis for high quality a-Si:H layers, in order to support continuous movement of the tape in the RTR process the chambers cannot be isolated from each other. The necessary pressure difference between the sputtering chambers and the PECVD (Plasma Enhanced Chemical Vapor Deposition) chambers is provided by pressure stages. They are optimized for high molecular flow resistance without any influence on the moving substrate tape. The back metal contacts and the semitransparent TCO (Transparent Conductive Oxide) contacts are deposited by rf magnetron sputtering, the a-Si:H film system is deposited by PECVD. Parallel to the film deposition a Nd:YAG laser patterning system is coupled into one chamber. This allows for instance a total manufacturing of integrated series connected solar modules in one system without breaking the vacuum. Our present investigations focus on the deposition of doped and intrinsic high quality a-Si:H based layers in neighboring chambers. The quality of semiconducting films deposited in adjacent chambers is studied with regard to potential contamination effects.
Image sensors in TFA (Thin Film on ASIC) technology have been successfully fabricated and tested. This paper provides a survey of TFA research results so far and outlines future perspectives. The properties of different a-Si:H b/w and color thin film detectors are evaluated, including spectral sensitivity, dark current, temperature influence and transient behavior. Furthermore several TFA prototypes and emerging concepts are presented, ranging from a simple one-transistor cell design to a locally autoadaptive sensor.
Silicon carbide fiber-reinforced alumina bodies have been produced by ram extrusion. The Al2O3 powder and SiC fiber were milled together to give a dry dispersion of up to 30 vol % fiber which was subsequently mixed to a paste by high shear kneading using hydroxypropylmethylcellulose solutions as the binder phase. Extruded bodies with green densities ranging between 56 and 63% full theoretical density were achieved. The paste flow behavior was characterized using physically based equations which show that for any given moisture content the pressure drop and the constituent paste parameters are all systematically reduced as the fiber loading is increased. This observation can be explained almost completely by combining packing theory with the paste rheology data. Fiber interactions within the paste and the die system appear not to greatly influence the rheological character of the material. It is shown statistically that the fibers are homogeneously dispersed throughout the paste mass after extrusion. Image analysis has been used to aid in macrodefect analysis, and it is shown that the optimum concentration of fiber was 20 vol % with a quantity of binder sufficient to give an initial yield stress of 2 MPa.
Band gap and defect engineered amorphous silicon based nipin photo diodes with bias controlled spectral response have been fabricated successfully. The devices exhibit good linearity over a wide illumination range and linearly independent spectral response curves which are required to generate a standard RGB-signal. In the bias range from -1.5 V to 1.5 V a dynamic range exceeding 90 dB for two color sensors and 80 dB for three color sensors has been observed. The general operation principle of the multispectral photo diode is discussed using a numerical simulation program. The model describes the defect state distribution of dangling bonds according to the defect-pool model and uses coherent wave propagation in the device to calculate the profile of photo generated carriers. Additionally, an analytical model has been developed to be included into standard circuit simulation programs like SPICE (Simulation Program with Integrated Circuit Emphasis). The analytical model uses linear field approximations in both i-layers of the device.
A TFA image sensor consists of an amorphous silicon based multilayer structure on top of a crystalline ASIC. The Multilayer acts as the optical detector, whereas the ASIC performs analog or digital signal processing for each individual pixel. Depending on the operation Mode, the dynamic range of the detector exceeds the performance of conventional CCDs by far. Pixel electronics which is adapted to the requirements of the detector can thereby maximize the dynamic range of the complete sensor array. Crosstalk among adjacent pixels can be eliminated by technological or electronic Means.
A novel α-Si(C):H color sensor array has been developed. In this device a single pixel consists of a combination of an amorphous silicon nipin detector and a crystalline operational amplifier. Steady state and transient opto electronic behavior of the nipin structure have been studied in order to optimize the design of the image sensor. Nipin structures are found to exhibit excellent dynamic range (125 dB) and linearity. The crystalline electronics causes only very little signal distortion which makes this sensor device a potential candidate for color image capture and processing for a wide range of illumination levels.
Amorphous silicon based n-i-p-i-n structures may be used as color detectors. A simulation program has been developed which allows the examination of the spatial distribution of carrier concentrations, electric field and current densities under different illumination conditions. Furthermore current/voltage- and monochromatic response curves are presented. The results of the simulation point out that the defect density in the p-layer has a major influence on device performance.