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971.
Invasive fungal infections occur frequently in neutropenic patients although only in recent years has the role of emerging fungi been clearly established. We describe two cases of fungemia caused by Trichosporon beigelii and Rhodotorula glutinis respectively in two neutropenic patients with hematological malignancies who were treated with amphotericin B. The first patient, with refractory multiple myeloma, died following massive pneumonia despite therapy with amphotericin B and granulocyte-colony stimulating factor (G-CSF); the second patient, with relapsed acute lymphatic leukemia and persistent fever without any other clinical evidence, finally recovered. Amphotericin B continues to be considered the "gold standard" in the treatment of invasive mycoses although other approaches need to be tested for refractory infections. 相似文献
972.
Eight typically developing children first learned to select pictures in response to dictated words in a three-choice matching-to-sample format. Next, the matching-to sample baseline was transformed via a stimulus control shaping procedure: Matching trials displayed two pictures and a third stimulus (termed a "blank" comparison). The blank was to be selected if the dictated sample did not match either of the displayed pictures. The blank comparison baseline was then used to evaluate the children's response to matching displays that presented novel sample and comparison stimuli. The blank comparison method permitted the children to indicate whether the novel sample-comparison pair were related (by selecting the picture) or not related (by selecting the blank). The method was used to evaluate emergent symbolic mapping and learning of new word:picture matching relations by the children. This study illustrates new, potentially more informative methods for analyzing symbol mapping in young children. The methods were shown to have considerable promise for advancing theoretical analyses of emergent mapping in both behavior analytic and developmental language research. 相似文献
973.
Although the actual visual simultaneous localization and mapping (SLAM) algorithms provide highly accurate tracking and mapping, most algorithms are too heavy to run live on embedded devices. In addition, the maps they produce are often unsuitable for path planning. To mitigate these issues, we propose a completely closed-loop online dense RGB-D SLAM algorithm targeting autonomous indoor mobile robot navigation tasks. The proposed algorithm runs live on an NVIDIA Jetson board embedded on a two-wheel differential-drive robot. It exhibits lightweight three-dimensional mapping, room-scale consistency, accurate pose tracking, and robustness to moving objects. Further, we introduce a navigation strategy based on the proposed algorithm. Experimental results demonstrate the robustness of the proposed SLAM algorithm, its computational efficiency, and its benefits for on-the-fly navigation while mapping. 相似文献
974.
Subham Ghosh Nabadyuti Barman Eliovardo Gonzalez-Correa Madhulika Mazumder Aryan Zaveri Raynald Giovine Alexis Manche Swapan K. Pati Raphaële J. Clément Premkumar Senguttuvan 《Advanced functional materials》2021,31(48):2105463
Vanadium multiredox-based NASICON-NazV2−yMy(PO4)3 (3 ≤ z ≤ 4; M = Al3+, Cr3+, and Mn2+) cathodes are particularly attractive for Na-ion battery applications due to their high Na insertion voltage (>3.5 V vs Na+/Na0), reversible storage capacity (≈150 mA h g−1), and rate performance. However, their practical application is hindered by rapid capacity fade due to bulk structural rearrangements at high potentials involving complex redox and local structural changes. To decouple these factors, a series of Mg2+-substituted Na3+yV2−yMgy(PO4)3 (0 ≤ y ≤ 1) cathodes is studied for which the only redox-active species is vanadium. While X-ray diffraction (XRD) confirms the formation of solid solutions between the y = 0 and 1 end members, X-ray absorption spectroscopy and solid-state nuclear magnetic resonance reveal a complex evolution of the local structure upon progressive Mg2+ substitution for V3+. Concurrently, the intercalation voltage rises from 3.35 to 3.45 V, due to increasingly more ionic V O bonds, and the sodium (de)intercalation mechanism transitions from a two-phase for y ≤ 0.5 to a solid solution process for y ≥ 0.5, as confirmed by in operando XRD, while Na-ion diffusion kinetics follow a nonlinear trend across the compositional series. 相似文献
975.
976.
High Aspect Ratio Sub‐Micrometer Channels Using Wet Etching: Application to the Dynamics of Red Blood Cell Transiting through Biomimetic Splenic Slits
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Priya Gambhire Scott Atwell Cécile Iss Frédéric Bedu Igor Ozerov Catherine Badens Emmanuèle Helfer Annie Viallat Anne Charrier 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(32)
Nanoparticles delivering drugs, disseminating cancer cells, and red blood cells (RBCs) during splenic filtration must deform and pass through the sub‐micrometer and high aspect ratio interstices between the endothelial cells lining blood vessels. The dynamics of passage of particles/cells through these slit‐like interstices remain poorly understood because the in vitro reproduction of slits with physiological dimensions in devices compatible with optical microscopy observations requires expensive technologies. Here, novel microfluidic PDMS devices containing high aspect ratio slits with sub‐micrometer width are molded on silicon masters using a simple, inexpensive, and highly flexible method combining standard UV lithography and anisotropic wet etching. These devices enabled revealing novel modes of deformations of healthy and diseased RBCs squeezing through splenic‐like slits (0.6–2 × 5–10 × 1.6–11 µm3) under physiological interstitial pressures. At the slit exit, the cytoskeleton of spherocytic RBCs seemed to be detached from the lipid membrane whereas RBCs from healthy donors and patients with sickle cell disease exhibited peculiar tips at their front. These tips disappeared much slower in patients' cells, allowing estimating a threefold increase in RBC cytoplasmic viscosity in sickle cell disease. Measurements of time and rate of RBC sequestration in the slits allowed quantifying the massive trapping of spherocytic RBCs. 相似文献
977.
Michèle Bodo 《先进材料力学与结构力学》2018,25(13):1140-1147
In a military context, blast loadings are encountered, with more or less severe consequences on structures in interaction with a shock wave, which travels in a field. With a need of protecting the fighter, the understanding of this physical dynamic phenomenon is of extreme importance to avoid body trauma induced by the primary blast. In this context, this study explores simulations of blast loading, and its interaction with a human torso biomechanical model previously developed, based on referenced experiments from the literature. The concept of similarities is also studied (peak pressure equivalence for long distance and large explosive mass and short distance and small explosive mass). Validations of numerical results are conducted using experimental data from the literature in terms of pressure peak as a function of scaled distance, and also in terms of pressure time history in the biomechanical model. Good agreement between the numerical results and the experimental peak pressure is achieved. 相似文献
978.
Screening of antigenic vesicular fluid proteins of Echinococcus multilocularis as potential viability biomarkers to monitor drug response in alveolar echinococcosis patients
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979.
William M. Jubb Richard A. A. Noble Jamie R. Dodd Andrew D. Nunn Jonathan D. Bolland 《河流研究与利用》2023,39(6):1054-1066
Anthropogenic structures extensively fragment riverine systems, reducing longitudinal connectivity, inhibiting migration and leading to severe declines in many fish populations, especially for diadromous species. This study investigated the upstream spawning migration of anadromous river lamprey (Lampetra fluviatilis) in a heavily fragmented tributary of the Humber Estuary, the location of one of the largest UK river lamprey populations. Overall, this study quantified river lamprey migration, spawning habitat distribution and historic river levels to develop a novel empirical index to understand the impact of man-made barriers and prioritise their remediation. Passage at all weirs only occurred during episodic high river levels, often after prolonged delays with no lamprey passing below average levels for the time of year or utilising the fish pass at the first weir (T1) at the tidal limit. Barrier passage opportunities at the first four weirs were only possible for 30.3%, 38.7%, 52.1% and 6.7% of the migration period, but were lower and severely limited in 15 of the last 21 years. In addition, more lamprey (60%, n = 18) were last detected in reaches with no spawning habitat than in spawning habitat (40%, n = 12). Given the impassibility of, and lack of retreat from, T1 to other Humber tributaries, the River Trent is currently considered an ecological trap for a large proportion of lamprey that enter from the Humber Estuary. This passage should be urgently remediated, per the prioritisation index presented here, to aid river lamprey conservation, especially given their status as a designated feature of the Humber SAC. 相似文献
980.
This study reports the plasma lipid changes in lambs receiving either ewes' milk or a reconstituted low fat milk powder during
the first eight days after birth. The liveweight gains of the lambs on the artificial diet was less than half that observed
in the lambs on the natural diet. The plasma lipid levels in the lambs on the natural diet increased considerably after birth
due to large increases in the concentrations of the cholesteryl ester, triglyceride and phospholipid fractions. For the lambs
on the artificial diet these fractions remained similar to those observed at birth. In both groups unesterified fatty acid
fractions decreased after birth. The main difference between the two groups of lambs was the large increase in C18 polyunsaturated fatty acids observed after birth in the lambs on the natural diet. The triene-tetraene ratio of the fatty
acids in the lambs on the natural diet decreased from 1.0 at birth to 0.08 after eight days whereas in the lambs on the artificial
diet the ratio increased to 2.9. These composition changes are discussed in relationship to the metabolism of essential fatty
acids in monogastric animals. 相似文献