321 research outputs found

    Exclusive electroproduction of φ mesons at 4.2 GeV

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    We studied the exclusive reaction ep⃗ e′p′φ using the φ⃗ K+K- decay mode. The data were collected using a 4.2 GeV incident electron beam and the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. Our experiment covers the range in Q2 from 0.7 to 2.2 GeV2, and W from 2.0 to 2.6 GeV. Taken together with all previous data, we find a consistent picture of φ production on the proton. Our measurement shows the expected decrease of the t slope with the vector-meson formation time cΔτ below 2 fm. At ⟨cΔτ⟩=0.6 fm, we measure bφ=2.27±0.42 GeV-2. The cross section dependence on W as W0.2±0.1 at Q2=1.3 GeV2 was determined by comparison with φ production at HERA after correcting for threshold effects. This is the same dependence as observed in photoproduction

    Opportunities to Intercalibrate Radiometric Sensors From International Space Station

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    Highly accurate measurements of Earth's thermal infrared and reflected solar radiation are required for detecting and predicting long-term climate change. We consider the concept of using the International Space Station to test instruments and techniques that would eventually be used on a dedicated mission such as the Climate Absolute Radiance and Refractivity Observatory. In particular, a quantitative investigation is performed to determine whether it is possible to use measurements obtained with a highly accurate reflected solar radiation spectrometer to calibrate similar, less accurate instruments in other low Earth orbits. Estimates of numbers of samples useful for intercalibration are made with the aid of year-long simulations of orbital motion. We conclude that the International Space Station orbit is ideally suited for the purpose of intercalibration

    Влияние равномерности внесения птичьего помета на урожайность зерновых культур

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    Possibility of increase of efficiency of poultry manure application due to more evenness of fertilizer application into the soil was investigated. Machines with a wide range of regulation of an application rate, for example ROU-6 with interval from 4 to 80 t/ha are for this purpose necessary. Efficiency of poultry manure application for grain crops was increased due to using of machines of drum type with optimum doses fertilizing (12-16 t/ha). An assessment of efficiency was carried out. The drums rotation speed, shovel quantity and shape, their installation angle and a design of the directing board were determined. The developed modified working of a spreader of drum type allowed to reduce unevenness of width fertilizing by 12-14 percent, on length of unit pass - by 5 percent. It was established that if the dose increases more than 8 t/ha, the crop productivity growths not significant. At reduction of fertilizing unevenness from 97 to 72 percent yield losses decrease by 54.4 percent. At reduction of fertilizing unevenness more than 97 percent, efficiency worsens by 58 percent. Poultry manure spreading by the machine and tractor unit MTZ-82.1 + ROU-6M afforded an yield by 38 percent higher, in comparison with the machine and tractor unit T-150K + PRT-10. At decrease in unevenness from 82 to 43 percent of barley loss decreased by 29 percent. It was revealed that spreading by machine ROU-6M provided a yield increase by 8.6 percent more, than by machine PRT-10. Yield losses because of spreading unevenness made: by the PRT-10 operating - 30 percent; by the ROU-6M operating - 0.33 percent. The grain yield increase was higher thanks to more evenness of fertilizer application by ROU-6M with the new spreading working element.Исследовали возможность повышения эффективности применения птичьего помета благодаря более равномерному внесению удобрения в почву. Для этого необходимы машины с широким диапазоном регулирования дозы внесения, например РОУ-6, с помощью которой можно вносить от 4 до 80 т/га. Эффективность применения птичьего помета повышали, используя машины барабанного типа для внесения под зерновые культуры оптимальных доз удобрения (12-16 т/га). Оценили результатаы при различной равномерности распределения. Определили угловую скорость вращения барабанов, количество и форму лопаток, углов их установки и конструкции направляющего щита. Разработанный модифицированный рабочий орган разбрасывателя барабанного типа позволил снизить неравномерность внесения помета по ширине на 12-14 процентов, по длине прохода агрегата - на 5 процентов. Установили, что с ростом дозы помета более 8 т/га значительного увеличения урожайности не происходит. При сокращении неравномерности внесения с 97 до 72 процентов потери урожая снижаются на 54,4 процента. При неравномерности внесения помета 97 процентов эффективность ухудшается на 58 процентов. Внесение птичьего помета машинно-тракторным агрегатом МТЗ-82.1 + РОУ-6М обеспечило прибавку урожая на 38 процентов выше, по сравнению с машинно-тракторным агрегатом Т-150К + ПРТ-10. При снижении неравномерности внесения помета с 82 до 43 процентов потери урожая ячменя уменьшились на 29 процентов. Выявили, что внесение помета машиной РОУ-6М обеспечило прибавку урожая на 8,6 процента больше, чем машиной ПРТ-10. Потери урожая от неравномерности внесения составили: при работе ПРТ-10 - 30 процентов; при работе РОУ-6М - 0,33 процента. При применении РОУ-6М с новым разбрасывающим рабочим органом прибавка урожая зерна была выше благодаря более равномерному внесению помета

    Дыхательная реабилитация у больных вирусной пневмонией на фоне новой коронавирусной инфекции

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    Pulmonary rehabilitation in COVID-19 patients with pneumonia is associated with better treatment outcomes. However, existing protocols have never been evaluated in randomized control studies. The aim. To evaluate the effectiveness of newly-developed pulmonary rehabilitation protocol compared to basic Russian COVID-19 guidelines for patients with oxygenation index (OI) between 200 and 400 points without IMV. Methods. Based on literature reviews and own clinical experience, standard rehabilitation protocol was designed and tailored for specific needs of low-OI patients. Two clinical centers participated in the study and included total 73 patients in main group. Control group included 73 retrospective patients based in propensity score; this patients received standard protocol of early pneumonia activation from official COVID-19 guidelines. Ten-days clinical outcomes were assessed based on parameter distribution type. Results. Evidence show significant difference in required time of continuous oxygen support in (5.1 ± 3.3 vs 8.0 ± 4.6 days for main and control group respectively. Main group also had mildly better functional. We’ve observed less mortality in main group, but attribute it not to the program, but for growing experience of health professionals and decreased loads on health system. Malignancy as comorbidity was considered a significant cofactor also. Conclusion. New pulmonary rehabilitation protocol improves clinical outcomes in critical COVID-19 patients by decreasing the demand fox oxygen support.При использовании дыхательной реабилитации при пневмонии, ассоциированной с новой коронавирусной инфекцией (НКИ), отмечено улучшение результатов лечения. Однако типовые протоколы дыхательной реабилитации для тяжелых форм коронавирусной пневмонии по данным рандомизированных исследований до настоящего момента не оценивались. Целью рандомизированного клинического исследования, проведенного в 2 клинических центрах, явилось определение эффективности протокола дыхательной реабилитации у больных с индексом оксигенации < 400 и > 200 при самостоятельном дыхании или кислородной поддержке по сравнению с пациентами, у которых реабилитация не проводилась. Материалы и методы. В исследовании приняли участие пациенты (n = 146) с ДН, отобранные методом ретроспективной псевдорандомизации среди больных, проходивших лечение ранее. Разработан протокол из 5 последовательных упражнений дыхательной гимнастики. Пациентам основной группы (n = 73) к лечению в течение 10 дней добавлена исследуемая реабилитационная программа, затем оценивались результаты. Результаты. Получено достоверное различие продолжительности непрерывной кислородной поддержки между группами (5,1 ± 3,3 дня vs 8,0 ± 4,6 дня). При анализе в подгруппах важной самостоятельной ковариатой исхода оказалось наличие онкологического заболевания. Заключение. При использовании комплекса лечебной физической культуры в остром периоде течения НКИ повышается эффективность лечения за счет раннего снижения потребности в кислородной поддержке, ускоренной нормализации индекса оксигенации, повышения толерантности к физической нагрузке

    Application of machine vision technology for focused laser effect accuracy improvement in microelectronic structures research and semiconductor microprocessing

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    Machine vision is a field of artificial intelligence that deals with processing images and videos using special algorithms. This allows devices to analyze visual information. Machine vision helps with tasks such as pattern recognition, image segmentation, object detection, and tracking. In microscopy, machine vision plays an important role, particularly in laser scanning microscopy (LSM). Laser scanning microscopy, laser scribing, and laser correction of the topology of semiconductor crystals are important technological processes in the production, control and adjustment of semiconductor crystals both on debug samples and as part of a test batch on a wafer. Laser exposure allows not only mechanically separate crystals, but also carry out more delicate and minimally invasive actions, in particular, adjustments to the values of thin-film resistors or burning of bridges necessary to adjust the circuit and disable unused blocks of the crystal. The paper lists the main parameters of the positioning system as part of the laser scanning setup, their impact on the quality of scanning and exposure to focused radiation at control points. The principles of machine vision algorithms when working with the image of the scanned object and the results of testing in the task of automated laser burning of bridges on a semiconductor wafer are described. Since the number of bridges can reach tens of thousands, and positioning systems have significant errors, machine vision allows you to correct the area and accuracy of laser exposure at any stage of scanning, which significantly improves the quality and efficiency of the process

    Two-gluon form factor of the nucleon and J/ψJ/\psi photoproduction

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    We argue that the t-dependence of the two-gluon form factor of the nucleon should be given by Γ(t)=(1t/m2g2)2\Gamma(t)=(1-t/m_{2g}^2)^{-2} with m2g21GeV2m_{2g}^2\approx 1 GeV^2. We demonstrate that this form provides a good description of the t-dependence of the cross section of the elastic photoproduction of J/ψJ/\psi-mesons between the threshold region of Eγ=11GeVE_{\gamma}=11 GeV (Cornell), Eγ=19GeVE_{\gamma}=19 GeV (SLAC) and Eγ=100GeVE_{\gamma}=100 GeV (FNAL) including the strong energy dependence of the t-slope. It is also well matched with the recent HERA data. The same assumption explains also the t-dependence of ϕ\phi-meson electroproduction near threshold at W=2.3GeV,Q2=1.0GeV2W=2.3 GeV, Q^2=1.0 GeV^2.Comment: 10 pages, 4 figure

    Effective interaction between helical bio-molecules

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    The effective interaction between two parallel strands of helical bio-molecules, such as deoxyribose nucleic acids (DNA), is calculated using computer simulations of the "primitive" model of electrolytes. In particular we study a simple model for B-DNA incorporating explicitly its charge pattern as a double-helix structure. The effective force and the effective torque exerted onto the molecules depend on the central distance and on the relative orientation. The contributions of nonlinear screening by monovalent counterions to these forces and torques are analyzed and calculated for different salt concentrations. As a result, we find that the sign of the force depends sensitively on the relative orientation. For intermolecular distances smaller than 6A˚6\AA it can be both attractive and repulsive. Furthermore we report a nonmonotonic behaviour of the effective force for increasing salt concentration. Both features cannot be described within linear screening theories. For large distances, on the other hand, the results agree with linear screening theories provided the charge of the bio-molecules is suitably renormalized.Comment: 18 pages, 18 figures included in text, 100 bibliog

    Measurement of the Polarized Structure Function σLT\sigma_{LT^\prime} for p(e,eπ+)np(\vec{e},e'\pi^+)n in the Δ(1232)\Delta(1232) Resonance Region

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    The polarized longitudinal-transverse structure function σLT\sigma_{LT^\prime} has been measured using the p(e,eπ+)np(\vec e,e'\pi^+)n reaction in the Δ(1232)\Delta(1232) resonance region at Q2=0.40Q^2=0.40 and 0.65 GeV2^2. No previous σLT\sigma_{LT^\prime} data exist for this reaction channel. The kinematically complete experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. A partial wave analysis of the data shows generally better agreement with recent phenomenological models of pion electroproduction compared to the previously measured π0p\pi^0 p channel. A fit to both π0p\pi^0 p and π+n\pi^+ n channels using a unitary isobar model suggests the unitarized Born terms provide a consistent description of the non-resonant background. The tt-channel pion pole term is important in the π0p\pi^0 p channel through a rescattering correction, which could be model-dependent.Comment: 6 pages, LaTex, 5 eps figures: Submitted to PRC/Brief Reports v2: Updated referenc

    Prodigal: prokaryotic gene recognition and translation initiation site identification

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    <p>Abstract</p> <p>Background</p> <p>The quality of automated gene prediction in microbial organisms has improved steadily over the past decade, but there is still room for improvement. Increasing the number of correct identifications, both of genes and of the translation initiation sites for each gene, and reducing the overall number of false positives, are all desirable goals.</p> <p>Results</p> <p>With our years of experience in manually curating genomes for the Joint Genome Institute, we developed a new gene prediction algorithm called Prodigal (PROkaryotic DYnamic programming Gene-finding ALgorithm). With Prodigal, we focused specifically on the three goals of improved gene structure prediction, improved translation initiation site recognition, and reduced false positives. We compared the results of Prodigal to existing gene-finding methods to demonstrate that it met each of these objectives.</p> <p>Conclusion</p> <p>We built a fast, lightweight, open source gene prediction program called Prodigal <url>http://compbio.ornl.gov/prodigal/</url>. Prodigal achieved good results compared to existing methods, and we believe it will be a valuable asset to automated microbial annotation pipelines.</p
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