Experimental assessment of drag reduction by traveling waves in a turbulent pipe flow

We experimentally assess the capabilities of an active, open-loop technique for drag reduction in turbulent wall flows recently introduced by Quadrio et al. [J. Fluid Mech., v.627, 161, (2009)]. The technique consists in generating streamwise-modulated waves of spanwise velocity at the wall, that travel in the streamwise direction. A proof-of-principle experiment has been devised to measure the reduction of turbulent friction in a pipe flow, in which the wall is subdivided into thin slabs that rotate independently in the azimuthal direction. Different speeds of nearby slabs provide, although in a discrete setting, the desired streamwise variation of transverse velocity. Our experiment confirms the available DNS results, and in particular demonstrates the possibility of achieving large reductions of friction in the turbulent regime. Reductions up to 33% are obtained for slowly forward-traveling waves; backward-traveling waves invariably yield drag reduction, whereas a substantial drop of drag reduction occurs for waves traveling forward with a phase speed comparable to the convection speed of near-wall turbulent structures. A Fourier analysis is employed to show that the first harmonics introduced by the discrete spatial waveform that approximates the sinusoidal wave are responsible for significant effects that are indeed observed in the experimental measurements. Practical issues related to the physical implementation of this control scheme and its energetic efficiency are briefly discussed.Comment: Article accepted by Phys. Fluids. After it is published, it will be found at http://pof.aip.or

Damage quantification and reaction of bean genotypes (Phaseolus vulgaris L.) to Meloidogyne incognita race 3 and M. javanica.

The damage and the resistance levels of cultivars and accessions of common beans rescued in the South and mountain regions of Espírito Santo State, Brazil, to M. incognita race 3 and M. javanica parasitism were evaluated under a greenhouse. Four rescued bean genotypes ("FORT-10", "FORT-13", "FORT-16" and "FORT-19") and 2 commercial cultivars: "Pérola", and "Aporé", were tested. The cultivar "Rico-23" was included as standard of susceptibility to nematodes and non-inoculated plants constituted the control. Thus, the experiment was carried out in a completely randomized design in 3 (treatments considering nematodes) x 7 (genotypes and bean cultivars) factorial arrangement, with 7 replicates. Data were measured at 50 days after plant inoculation. For damage quantification, the following variables were evaluated: plant height (PHE), number of nodes (NNO), number of trifoliate leaves (NRT), fresh matter weight (FWE) and dry matter weight (DWE) of shoots, root weight (RWE), number of root nodules (NRO) and final population (FPO) of nematodes per root system. There were no significant differences between the effects caused by M. incognita and M. javanica, but both species showed inferior values of PHE, NNO, NRT, RWE, FWE and DWE compared to controls. Concerning the levels of resistance of bean plants to M. incognita, the genotypes "FORT-10", "FORT-13", "Aporé" and "FORT-16" behaved as moderately resistant, the cultivars "Rico 23" and "Pérola" low resistant, and the genotype "FORT-19" as highly susceptible. When parasitized by M. javanica, the beans "FORT-19", "Rico-23", "FORT-16" and "FORT-13" were low resistant, "Pérola" and "Aporé" susceptible and "FORT-10" highly susceptible

Поражения сердца у детей на фоне течения COVID-19

Ongoing research on SARS-CoV-2 showed the ability of a pathogen to affect cardio-vascular system in the form of myocarditis, dysrhythmia, cardiac failure, etc. According to an infectious diseases hospital in Omsk, changes in the heart were recorded in 3.3% of children hospitalized with COVID-19. Authors conducted a retrospective study of 24 children aged 1—17 years 11 months with a new coronavirus infection who recieved treatment in an infectious diseases hospital at the Budgetary Healthcare Institution of Omsk Oblast City Children's Clinical Hospital №3 in Omsk from October 2020 to December 2021. It was found that heart lesions were more often recorded in children over 10 years old, all males. In most patients, cardiac lesions developed in presence of concomitant pathology and were combined with lung damage. Clinical manifestations indicating involvement in the pathological process of the cardiovascular system appeared in addition to respiratory infection. They were mild and nonspecific.Продолжающиеся исследования в отношении SARS-CoV-2 показали возможность возбудителя поражать сердечно-сосудистую систему в виде миокардитов, нарушений ритма, сердечной недостаточности и др. По данным инфекционного стационара г. Омска, изменения со стороны сердца регистрировались у 3,3% госпитализированных детей с COVID-19. Материалы и методы. Было проведено ретроспективное исследование историй болезни 24 детей в возрасте от 1 года до 17 лет 11 месяцев с новой коронавирусной инфекцией, находившихся на лечении в инфекционном стационаре БУЗОО ГДКБ №3 г. Омска в период с октября 2020 года по декабрь 2021 г. Результаты. Было выявлено, что поражения сердца чаще регистрируются в группе детей старше 10 лет, мужского пола. У большинства пациентов поражения сердца развивались на фоне сопутствующей патологии и сочетались с поражением легких. Клинические проявления, свидетельствующие о вовлечении в патологический процесс сердечно-сосудистой системы, появлялись на фоне респираторной инфекции, были слабо выражены и неспецифичны

Клинический случай развития мультисистемного воспалительного синдрома у ребенка с новой коронавирусной инфекцией

Objective: The article deals with a clinical case of new coronavirus infection in a 1 5-year-old child who was receiving treatment in an infectious diseases hospital of City Children's Clinical Hospital №3 during the period from 1 0 October to 1 December 2020.Materials and methods. The diagnosis was confirmed through nasal swabs examination for the presence of SARS-CoV-2 RNA using PCR and SARS-CoV-2 IgM detection through ELISA.Results. The main feature of the infection course in the present patient was multisystem inflammatory syndrome development with long-term fever, maculopapular rash and multisystemic lesions including bilateral pneumonia, acute carditis and polyserositis.Цель: описание клинического случая новой коронавирусной инфекции у ребенка 15 лет, находившегося на лечении в инфекционном стационаре БУЗОО ГДКБ №3 г. Омска в период с 10 ноября по 1 декабря 2020 г.Материалы и методы. Диагноз был подтвержден исследованием мазков из носоглотки на наличие РНК SARS-CoV-2 методом ПЦР и обнаружением IgM к SARS-CoV-2 методом ИФА.Результаты. Особенностью течения коронавирусной инфекции у данного пациента явилось развитие мультисистемного воспалительного синдрома с длительной лихорадкой, пятнисто-папулезной сыпью, полиорганными поражениями, включающими двустороннюю пневмонию, острый кардит, полисерозит

Earliness and morphotypes of common wheat cultivars of Western and Eastern Siberia

The global and local climate changes determine the producing of highly-adaptive common (bread) wheat commercial cultivars of a new generation whose optimal earliness matches the climatic features of the territory where the cultivars are farmed. Principal component analysis involving our own and published data has been applied to investigate 98 commercial common wheat cultivars from Western and Eastern Siberia comparing their morphotypes; cultivar zoning time; length of the vegetation period; 1000-grain weight, and inheritance of spring growth habit. It demonstrated that the dominant Vrn gene polymorphism determining the spring growth habit of the Siberian cultivars was minimally polymorphic. In 75 % of the tested cultivars, the spring growth habit was controlled by digenic, namely dominant Vrn-A1 and Vrn-B1 genes. In 25 % of them (24 cultivars), spring growth habit is controlled by a single gene. In 19 and 5 of these cultivars spring growth habit is controlled by only one dominant gene, Vrn-B1 or Vrn-A1, respectively. In cv. Tulun 15, a trigenic control was identified. A conclusion about the optimality of the digenic control for the climatic conditions of both Western and Eastern Siberia has been confirmed. However, since none of the tested cultivars had the dominant Vrn-D1 gene typical of the regions of China and Central Asia bordering Siberia, it can be considered as an additional argument in favor of the European origin of Siberian common wheat cultivars. The revealed high frequency of the Vrn-B1c allele in the Western Siberian cultivars and the Vrn-B1a allele in the Eastern Siberian cultivars suggests their selectivity. The analysis also confirmed the dominance of red glume (ferrugineum, milturum) and awned spike (ferrugineum, erythrospermum) varieties in the Eastern Siberian cultivars, and white glume and awnedless spike (lutescens and albidum) ones in the Western Siberian cultivars. Small grain size cultivars are more typical of Eastern than Western Siberia. The retrospective analysis based on the cultivars’ zoning time included in the “State Register for Selection Achievements Admitted for Usage” brought us to the conclusion that the earliness/lateness of modern Siberian commercial cultivars was not regionally but rather zonally-associated (taiga, subtaiga, forest-steppe and steppe zones)

Estimation of black carbon emissions from Siberian fires using satellite observations of absorption and extinction optical depths

Black carbon (BC) emissions from open biomass burning (BB) are known to have a considerable impact on the radiative budget of the atmosphere at both global and regional scales; however, these emissions are poorly constrained in models by atmospheric observations, especially in remote regions. Here, we investigate the feasibility of constraining BC emissions from BB using satellite observations of the aerosol absorption optical depth (AAOD) and the aerosol extinction optical depth (AOD) retrieved from OMI (Ozone Monitoring Instrument) and MODIS (Moderate Resolution Imaging Spectroradiometer) measurements, respectively. We consider the case of Siberian BB BC emissions, which have the strong potential to impact the Arctic climate system. Using aerosol remote sensing data collected at Siberian sites of the AErosol RObotic NETwork (AERONET) along with the results of the fourth Fire Lab at Missoula Experiment (FLAME-4), we establish an empirical parameterization relating the ratio of the elemental carbon (EC) and organic carbon (OC) contents in BB aerosol to the ratio of AAOD and AOD at the wavelengths of the satellite observations. Applying this parameterization to the BC and OC column amounts simulated using the CHIMERE chemistry transport model, we optimize the parameters of the BB emission model based on MODIS measurements of the fire radiative power (FRP); we then obtain top-down optimized estimates of the total monthly BB BC amounts emitted from intense Siberian fires that occurred from May to September 2012. The top-down estimates are compared to the corresponding values obtained using the Global Fire Emissions Database (GFED4) and the Fire Emission Inventory–northern Eurasia (FEI-NE). Our simulations using the optimized BB aerosol emissions are verified against AAOD and AOD data that were withheld from the estimation procedure. The simulations are further evaluated against in situ EC and OC measurements at the Zotino Tall Tower Observatory (ZOTTO) and also against aircraft aerosol measurement data collected in the framework of the Airborne Extensive Regional Observations in SIBeria (YAK-AEROSIB) experiments. We conclude that our BC and OC emission estimates, considered with their confidence intervals, are consistent with the ensemble of the measurement data analyzed in this study. Siberian fires are found to emit 0.41±0.14&thinsp;Tg of BC over the whole 5-month period considered; this estimate is a factor of 2 larger and a factor of 1.5 smaller than the corresponding estimates based on the GFED4 (0.20&thinsp;Tg) and FEI-NE (0.61&thinsp;Tg) data, respectively. Our estimates of monthly BC emissions are also found to be larger than the BC amounts calculated using the GFED4 data and smaller than those calculated using the FEI-NE data for any of the 5 months. Particularly large positive differences of our monthly BC emission estimates with respect to the GFED4 data are found in May and September. This finding indicates that the GFED4 database is likely to strongly underestimate BC emissions from agricultural burns and grass fires in Siberia. All of these differences have important implications for climate change in the Arctic, as it is found that about a quarter of the huge BB BC mass emitted in Siberia during the fire season of 2012 was transported across the polar circle into the Arctic. Overall, the results of our analysis indicate that a combination of the available satellite observations of AAOD and AOD can provide the necessary constraints on BB BC emissions.</p