118 research outputs found
Fano Resonance Between Mie and Bragg Scattering in Photonic Crystals
We report the observation of a Fano resonance between continuum Mie
scattering and a narrow Bragg band in synthetic opal photonic crystals. The
resonance leads to a transmission spectrum exhibiting a Bragg dip with an
asymmetric profile, which can be tunably reversed to a Bragg rise. The Fano
asymmetry parameter is linked with the dielectric contrast between the
permittivity of the filler and the specific value determined by the opal
matrix. The existence of the Fano resonance is directly related to disorder due
to non-uniformity of a-SiO2 opal spheres. Proposed theoretical "quasi-3D" model
produces results in excellent agreement with the experimental data
Успешное лечение пациента с тяжелым сепсисом и синдромом полиорганной недостаточности, осложнившими течение гнойных ран различной локализации
The article describes the complex surgical treatment of a patient with a bilateral hip phlegmon complicated by severe sepsis, multiple organ failure syndrome (cardiac, respiratory), as well as deep pressure ulcers of various depths and localization under the primarily diagnosed diabetes mellitus.В статье представлен опыт комплексного хирургического лечения пациента с флегмоной обоих бедер, осложнившейся развитием тяжелого сепсиса с синдромом полиорганной недостаточности (сердечной, дыхательной) и глубокими пролежнями различной локализации на фоне впервые выявленного сахарного диабета
Oxygen-rich microporous carbons with exceptional hydrogen storage capacity
Porous carbons have been extensively investigated for hydrogen storage but, to date, appear to have an upper limit to their storage capacity. Here, in an effort to circumvent this upper limit, we explore the potential of oxygen-rich activated carbons. We describe cellulose acetatederived carbons that combine high surface area (3800 m2 g-1) and pore volume (1.8 cm3 g-1) that arise almost entirely (> 90%) from micropores, with an oxygen-rich nature. The carbons exhibit enhanced gravimetric hydrogen uptake (8.1 wt% total, and 7.0 wt% excess) at -196 ºC and 20 bar, rising to a total uptake of 8.9 wt% at 30 bar, and exceptional volumetric uptake of 44 g l-1 at 20 bar, and 48 g l-1 at 30 bar. At room temperature they store up to 0.8 wt% (excess) and 1.2 wt% (total) hydrogen at only 30 bar, and their isosteric heat of hydrogen adsorption is above 10 kJ mol-1
Interaction of Hydrogen with Graphitic Surfaces, Clean and Doped with Metal Clusters
Producción CientíficaHydrogen is viewed as a possible alternative to the fossil fuels in transportation.
The technology of fuel-cell engines is fully developed, and the outstanding
remaining problem is the storage of hydrogen in the vehicle. Porous materials,
in which hydrogen is adsorbed on the pore walls, and in particular nanoporous
carbons, have been investigated as potential onboard containers. Furthermore,
metallic nanoparticles embedded in porous carbons catalyze the dissociation of
hydrogen in the anode of the fuel cells. For these reasons the interaction of
hydrogen with the surfaces of carbon materials is a topic of high technological
interest. Computational modeling and the density functional formalism (DFT)
are helping in the task of discovering the basic mechanisms of the interaction
of hydrogen with clean and doped carbon surfaces. Planar and curved graphene
provide good models for the walls of porous carbons. We first review work on
the interaction of molecular and atomic hydrogen with graphene and graphene nanoribbons, and next we address the effects due to the presence of metal clusters
on the surface because of the evidence of their role in enhancing hydrogen
storage.Ministerio de Economía, Industria y Competitividad (Grant MAT2014-54378-R
Study of the characteristics of photoresistors based on hydrochemically deposited films of Pb0.902Sn0.098Se solid solution
Tapping into non-English-language science for the conservation of global biodiversity.
The widely held assumption that any important scientific information would be available in English underlies the underuse of non-English-language science across disciplines. However, non-English-language science is expected to bring unique and valuable scientific information, especially in disciplines where the evidence is patchy, and for emergent issues where synthesising available evidence is an urgent challenge. Yet such contribution of non-English-language science to scientific communities and the application of science is rarely quantified. Here, we show that non-English-language studies provide crucial evidence for informing global biodiversity conservation. By screening 419,679 peer-reviewed papers in 16 languages, we identified 1,234 non-English-language studies providing evidence on the effectiveness of biodiversity conservation interventions, compared to 4,412 English-language studies identified with the same criteria. Relevant non-English-language studies are being published at an increasing rate in 6 out of the 12 languages where there were a sufficient number of relevant studies. Incorporating non-English-language studies can expand the geographical coverage (i.e., the number of 2° × 2° grid cells with relevant studies) of English-language evidence by 12% to 25%, especially in biodiverse regions, and taxonomic coverage (i.e., the number of species covered by the relevant studies) by 5% to 32%, although they do tend to be based on less robust study designs. Our results show that synthesising non-English-language studies is key to overcoming the widespread lack of local, context-dependent evidence and facilitating evidence-based conservation globally. We urge wider disciplines to rigorously reassess the untapped potential of non-English-language science in informing decisions to address other global challenges. Please see the Supporting information files for Alternative Language Abstracts
EXPERIMENTAL STUDY OF SPECIFIC ACTIVITY OF 1,3-DIAZINON-4 COMPOUND PYaTdl DERIVATIVE IN VIVO
Aim. Study anti-leprosy activity of a 1.3-diazinon-4 compound derivative under the laboratory code PYaTd 1 on the model of intra-plantar infection of mice and evaluate the character of its antibacterial effect. Materials and methods. Study of specific activity was carried out in vivo on the experimental model of leprosy, proposed by Shepard C.C., that assumes execution of intra-plantar infection of mice with a suspension of mycobacteria, produced from lepromas or autopsy tissue of a non-treated leprosy infected, or from tissues of experimental mice, previously infected with Mycobacterium leprae from non-treated patients. The study was carried out on 120 C BA line mice infected with M. leprae (VIII passage) from patient M. Dapsone and PYaTdl compound were administered to animals next day after the infection with forage at a dose of 25 mg/kg for 4.5, 6, 9 and 11 months. The mice were split into 3 groups: control (infected without treatment), comparison (infected, receiving dapsone), experimental (infected, receiving PYaTd 1). After the control term the mice were euthanized under chloroform anesthesia. Suspensions for quantification of mycobacteria were prepared from paw pads. Smears were stained by Ziehl-Nilsson. Results. After 4.5 months the intensity of infect reproduction under the effect of dapsone and PYaTd 1 was reduced compared with control by 18 - 25 times. After a 6-month course - by 50 - 75% and after 9 months - by 85 - 90%. After 11 months in mice that had received PYaTd 1, an intensive suppression of microorganism reproduction was observed: the yield in paws was 70 times lower than in control. In the group that had received dapsone, a reduction of the number of mycobacteria by 20 - 25 times was detected, it was significantly less effective than under the conditions of PYaTd 1 administration. Conclusion. A novel 1.3-diazinon-4 derivative under the code PYaTdl can actively supress reproduction of M. leprae, that gives evidence regarding its specific anti-mycobacterial activity and determines perspectives of its further studies
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