Seventeen Middle Pleistocene crania from the Sima de los Huesos site (Atapuerca, Spain) are analyzed, including seven new specimens. This sample makes it possible to thoroughly characterize a Middle ...Pleistocene hominin paleodeme and to address hypotheses about the origin and evolution of the Neandertals. Using a variety of techniques, the hominin-bearing layer could be reassigned to a period around 430,000 years ago. The sample shows a consistent morphological pattern with derived Neandertal features present in the face and anterior vault, many of which are related to the masticatory apparatus. This suggests that facial modification was the first step in the evolution of the Neandertal lineage, pointing to a mosaic pattern of evolution, with different anatomical and functional modules evolving at different rates.
The recently initiated Arecibo Legacy Fast ALFA (ALFALFA) survey aims to map ~7000 deg2 of the high Galactic latitude sky visible from Arecibo, providing a H I line spectral database covering the ...redshift range between -1600 and 18,000 km s-1 with ~5 km s-1 resolution. Exploiting Arecibo's large collecting area and small beam size, ALFALFA is specifically designed to probe the faint end of the H I mass function in the local universe and will provide a census of H I in the surveyed sky area to faint flux limits, making it especially useful in synergy with wide-area surveys conducted at other wavelengths. ALFALFA will also provide the basis for studies of the dynamics of galaxies within the Local Supercluster and nearby superclusters, allow measurement of the H I diameter function, and enable a first wide-area blind search for local H I tidal features, H I absorbers at z < 0.06, and OH megamasers in the redshift range 0.16 < z < 0.25. Although completion of the survey will require some 5 years, public access to the ALFALFA data and data products will be provided in a timely manner, thus allowing its application for studies beyond those targeted by the ALFALFA collaboration. ALFALFA adopts a two-pass, minimum intrusion, drift scan observing technique that samples the same region of sky at two separate epochs to aid in the discrimination of cosmic signals from noise and terrestrial interference. Survey simulations, which take into account large-scale structure in the mass distribution and incorporate experience with the ALFA system gained from tests conducted during its commissioning phase, suggest that ALFALFA will detect on the order of 20,000 extragalactic H I line sources out to z ~ 0.06, including several hundred with H I masses M < 107.5 M.
A New Hybrid DGTD/FDTD Method in 2-D Garcia, S.G.; Fernandez Pantoja, M.; de Jong van Coevorden, C.M. ...
IEEE microwave and wireless components letters,
12/2008, Letnik:
18, Številka:
12
Journal Article
Recenzirano
In this letter, we present a method to efficiently hybridize the discontinuous Galerkin time domain method (DGTD) with the classical finite difference time domain method (FDTD). The main advantage of ...this hybrid method is that it maintains the generality of FDTD to treat the main part of a complex inhomogeneous problem, applying only DGTD for accurately taking into account the geometrical details of the objects which would not be properly treated with the usual staircased approximation of the classical FDTD.
Leukocyte count is routinely performed for diagnostic purposes and is rapidly emerging as a significant biomarker for a wide array of diseases. Additionally, leukocytes have demonstrated considerable ...promise in novel cell-based immunotherapies. However, the direct retrieval of leukocytes from whole blood is a significant challenge due to their low abundance compared to erythrocytes. Here, we introduce a microfluidic-based platform that isolates and recovers leukocytes from diluted whole blood in a single step. Our platform utilizes a novel, sheathless method to initially sediment and focus blood cells into a dense stream while flowing through a tubing before entering the microfluidic device. A hexagonal-shaped structure, patterned at the device's inlet, directs all the blood cells against the channel's outer walls. The focused cells are then separated based on their size using the deterministic lateral displacement (DLD) microfluidic technique. We evaluated various parameters that could influence leukocyte separation, including different focusing structures (assessed both computationally and experimentally), the orientation of the tubing-chip interface, the effects of blood sample hematocrit (dilution), and flow rate. Our device demonstrated the ability to isolate leukocytes from diluted blood with a separation efficiency of 100%, a recovery rate of 76%, and a purity of 80%, while maintaining a cell viability of 98%. The device operates for over 30 min at a flow rate of 2 μL min
. Furthermore, we developed a handheld pressure controller to drive fluid flow, enhancing the operability of our platform outside of central laboratories and enabling near-patient testing. Our platform can be integrated with downstream cell-based assays and analytical methods that require high leukocyte purity (80%), ranging from cell counting to diagnostics and cell culture applications.
This study aimed to evaluate the concurrent validity of two different inertial measurement units for measuring spatiotemporal parameters during running on a treadmill, by comparing data with a ...high-speed video analysis (VA) at 1,000 Hz. Forty-nine endurance runners performed a running protocol on a treadmill at comfortable velocity (i.e., 3.25 ± 0.36 m.s-1). Those wearable devices (i.e., Stryd™ and RunScribe™ systems) were compared to a high-speed VA, as a reference system for measuring spatiotemporal parameters (i.e. contact time CT, flight time FT, step frequency SF and step length SL) during running at comfortable velocity. The pairwise comparison revealed that the Stryd™ system underestimated CT (5.2%, p < 0.001) and overestimated FT (15.1%, p < 0.001) compared to the VA; whereas the RunScribe™ system underestimated CT (2.3%, p = 0.009). No significant differences were observed in SF and SL between the wearable devices and VA. The intra class correlation coefficient (ICC) revealed an almost perfect association between both systems and high-speed VA (ICC > 0.81). The Bland-Altman plots revealed heteroscedasticity of error (r2 = 0.166) for the CT from the Stryd™ system, whereas no heteroscedasticity of error (r2 < 0.1) was revealed in the rest of parameters. In conclusion, the results obtained suggest that both foot pods are valid tools for measuring spatiotemporal parameters during running on a treadmill at comfortable velocity. If the limits of agreement of both systems are considered in respect to high-speed VA, the RunScribe™ seems to be a more accurate system for measuring temporal parameters and SL than the Stryd™ system.
The objectives of this study were twofold: firstly, to study the thermal decomposition of Cu
2
ZnSnS
4
(CZTS) in the air or inert atmosphere, and secondly, to study the impact on the structural and ...optical properties of pure CZTS nanoparticles annealing in an air atmosphere at temperatures of 300 and, 400 °C. CZTS nanoparticles were synthesized at 200 °C through a hydrothermal-microwave technique. CZTS nanoparticles were characterized by TGA, XRD, Raman, SEM, HR-TEM, and UV–Vis techniques to analyze decomposition temperature, crystalline structure, vibrational transitions, morphology, d-spaces, and optical properties, respectively. The as-synthesized particles at 200 °C showed 6 nm size and were annealed at 300, 400, and 500 °C in an air atmosphere. TGA analysis shows CZTS nanoparticles remain stable inside the air atmosphere until 400 °C. However, this material is stable in the inert atmosphere until 600 °C. XRD pattern confirmed the decomposition of CZTS in an air atmosphere at 500 °C to Cu
2
S, SnO
2
, Zn(SO
4
), Cu(SO
4
), and Cu
2
(SO
4
)O. CZTS nanoparticles were stable up to 400 °C, showing a better optical property in the crystal size and structure. The band gap value of CZTS nanoparticles decreases with the heat treatment, which gives a better advantage to light absorption in the visible range for better optoelectronic applications.
A method to simulate an open boundary problem within the finite difference time domain approach for the emission of photo-conductive antennas is presented here. For this purpose, we use convolutional ...perfectly matched layers (CPMLs). In these devices, the semiconductor region, where transient currents are present in simulation time, is considered to be an "active" medium. This medium is extended virtually beyond its boundaries or the computational domain limits. We explain in this communication how to simulate the transient state of a semiconductor in a CPML region as well as the potential of the method developed to solve conventional practical applications.
This letter explores the influence of the geometry of bias electrodes in the performance of terahertz (THz) photoconductive antennas (PCAs). To this end, a methodology is presented to calculate ...numerically the operational bandwidth and radiation efficiency of the PCAs. The procedure is validated through a comparison to experimental measurements. Also, results are depicted from numerical simulations of different PCAs under varying conditions of bias voltage, doping factor, and incident optical power. It is concluded that an appropriate configuration of the electrodes may double the efficiency of the antennas, with a penalty in the bandwidth of the radiated pulse usually smaller than 10%.
Abstract Objective To describe the variability in the prescription of non-biologic disease-modifying antirheumatic drugs (nbDMARDs) for the treatment of spondyloarthritis (SpA) in Spain and to ...explore which factors relating to the disease, patient, physician, and/or center contribute to these variations. Methods A retrospective medical record review was performed using a probabilistic sample of 1168 patients with SpA from 45 centers distributed in 15/19 regions in Spain. The sociodemographic and clinical features and the use of drugs were recorded following a standardized protocol. Logistic regression, with nbDMARDs prescriptions as the dependent variable, was used for bivariable analysis. A multilevel logistic regression model was used to study variability. Results The probability of receiving an nbDMARD was higher in female patients OR = 1.548; 95% confidence interval (CI): 1.208–1.984, in those with elevated C-reactive protein (OR = 1.039; 95% CI: 1.012–1.066) and erythrocyte sedimentation rate (OR = 1.012; 95% CI: 1.003–1.021), in those with a higher number of affected peripheral joints (OR = 12.921; 95% CI: 2.911–57.347), and in patients with extra-articular manifestations like dactylitis (OR = 2.997; 95% CI: 1.868–4.809), psoriasis (OR = 2.601; 95% CI: 1.870–3.617), and enthesitis (OR = 1.717; 95% CI: 1.224–2.410). There was a marked variability in the prescription of nbDMARDs for SpA patients, depending on the center (14.3%; variance 0.549; standard error 0.161; median odds ratio 2.366; p < 0.001). After adjusting for patient and center variables, this variability fell to 3.8%. Conclusion A number of factors affecting variability in clinical practice, and which are independent of disease characteristics, are associated with the probability of SpA patients receiving nbDMARDs in Spain.
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