314 research outputs found
Sapropel-based supports as novel macroporous carbon-mineral adsorbents for enzymatic active substances
The novel macroporous carbon-mineral Sapropel supports were obtained from lacustrine sapropel silts of freshwater lakes by annealing of semi-coke in the inert atmosphere. The specific surface area of these supports varied from 10 to 100 m2 /g, the total pore volume from 0.3 cm3 /g till 1.6 cm3 /g; macropores of diameters more than 2 μm were predominating. The Sapropel supports were studied for the adsorption/adhesion of enzymatic active substances, such as whole bacterial cells, and invertase-active fully destroyed baker's yeast cells (autolysates), and purified enzyme nitrilase. The heterogeneous biocatalysts with required enzymatic activity were prepared and their properties were studied in the corresponding bioconversion processes. The invertase-active biocatalysts exhibited high activity, 120-135 U/g, and stability; the half-times of their inactivation (t½) were more than 1000 h in the continuous process of sucrose hydrolysis at 50 °С. The nitrilase-active biocatalysts for “green” chemistry of nitriles possessed high activity, 350-500 U/g, and the t½ were estimated to be more than 100 h in the periodic process of hydration of acrylonitrile to acrylic acid at 22 °С
An overview and prospective on Al and Al-ion battery technologies
Aluminum batteries are considered compelling electrochemical energy storage systems because of the natural abundance of aluminum, the high charge storage capacity of aluminum of 2980 mA h g−1/8046 mA h cm−3, and the sufficiently low redox potential of Al3+/Al. Several electrochemical storage technologies based on aluminum have been proposed so far. This review classifies the types of reported Al-batteries into two main groups: aqueous (Al-ion, and Al-air) and non-aqueous (aluminum graphite dual-ion, Al-organic dual-ion, Al-ion, and Al-sulfur). Specific focus is given to Al electrolyte chemistry based on chloroaluminate melts, deep eutectic solvents, polymers, and “chlorine-free” formulations
Efficacy of surgical treatment of renal form of hyperparathyroidism
Objective: to study the efficacy of surgical treatment of primary hyperparathyroidism in risk of uronephrolithiasis progression. Material and Methods. The research involved 55 patients, the biochemical and clinical parameters before and after treatment with retrospective-prospective method of analysis were studied and analyzed. Results. It is established that the surgical treatment of patients with uronephrolithiasis is proved to be effective in 96,4% of the cases, as it allows to eliminate the classic symptoms of primary hyperparathyroidism, and urolithiasis. Improvement of laboratory hormonal and biochemical indices of mineral metabolism, and, consequently, reducing the severity of risk factors of urolithiasis is marked. Conclusion. Surgical treatment of renal forms of primary hyperparathyroidism is a pathogeneti-cally reasonable method. Parathyroidectomy performed in an adequate amount prevents relapses and progression of diseases that are the consequence of primary hyperparathyroidism.</p
Апробація ЗТ-ПЛР тест-системи для диференційної діагностики африканської та класичної чуми свиней
The first Ukrainian real-time reverse-transcriptase polymerase chain reaction (RT-qPCR) based test kit for the differential diagnosis of African (AFS) and Classical swine fever (CSF) has been developed in the Institute of Veterinary Medicine of NAAS. The proposed test kit allows simultaneous detection of three targets: ASFV DNA, CSFV cDNA and an internal control sample. The goal of this work was to provide an expert evaluation of the RT-qPCR kit for differential diagnosis of ASF and CSF according to appearance, analytical sensitivity, specificity and repeatability. Interdepartmental evaluation of the kit was conducted in the State Scientific and Research Institute of Laboratory Diagnostics and Veterinary and Sanitary Expertise (DNDILDEVSE) in accordance with the approved methodology. The RT-qPCR kit sensitivity was determined by testing 10-fold serial dilutions of the ASFV DNA and CSFV cDNA (concentration range was 103–100 copies/μl). For specificity determination reference samples of ASFV DNA different genotypes, ASF and CSF positive and negative field samples, as well as pathogens which cause similar to ASF and CSF clinical syndromes were used. Sample preparation and amplification were performed according to the test kit instructions. The amplification was accomplished on QuantStudio™ 5 System (Applied Biosystems). As a result of accomplished interdepartmental evaluation high sensitivity, specificity and repeatability of RT-qPCR kit were confirmed. In particular, it was determined that the limit of detection of the RT-qPCR kit was 5 copies of the ASFV and CSFV genomes per one reaction. The high specificity of the assay to ASFV (I, II, V, VIII, IX and X genotypes) and CSFV was confirmed. It was showп no cross-reactions with closely related pigs viruses (porcine circovirus type 2, porcine reproductive and respiratory syndrome virus and virus of Aujeszky's disease). The high enough repeatability of results was also confirmed. In conclusion, the obtained results are in compliance with the requirements of the RT-qPCR kit normative and technical documentation. This RT-qPCR kit will be recommended for use in veterinary medicine laboratories after its registration would be done.В Інституті ветеринарної медицини НААН уперше в Україні розроблено діагностичний набір для диференційної діагностики африканської (АЧС) та класичної чуми свиней (КЧС) методом зворотно-транскриптазної полімеразної ланцюгової реакції (ЗТ-ПЛР) у режимі реального часу. Розроблений діагностикум дозволяє одночасно детектувати три мішені: ДНК вірусу АЧС, кДНК вірусу КЧС і внутрішній контрольний зразок. Метою роботи було провести експертну оцінку діагностичного набору для диференційної діагностики АЧС та КЧС методом ПЛР у режимі реального часу за показниками: зовнішній вигляд, чутливість, специфічність і збіжність результатів. Міжвідомчі випробування діагностикуму було проведено на базі Державного НДІ з лабораторної діагностики та ветеринарно-санітарної експертизи (ДНДІЛДВСЕ) згідно з розробленою і затвердженою методикою. Для визначення чутливості діагностикуму досліджували серію 10-кратних розведень ДНК вірусу АЧС і кДНК КЧС (в концентрації 103–100 копій/мкл). Для визначення специфічності дослідували референтні зразки ДНК вірусу АЧС різних генотипів, польові зразки позитивні та негативні щодо АЧС, КЧС, а також сторонні збудники. Підготовку зразків та проведення ампліфікації проводили здіно з листівкою-вкладкою до діагностикуму. Ампліфікацію здійснювали на приладі QuantStudio™ 5 System, виробник «Applied Biosystems». У результаті роботи підтверджено високу чутливість, специфічність та збіжність діагностикуму. Зокрема визначено, що чутливість тест-системи становить близько 5 копій ДНК вірусу АЧС та 5 копій кДНК вірусу КЧС на одну реакцію. Підтверджено специфічність діагностикуму до вірусів АЧС (І, ІІ, V, VIII, IX,X генотипів) та КЧС. При цьому не спостерігалось неспецифічних реакцій зі сторонніми вірусами (цирковірус свиней 2-го типу, вірус репродуктивно-респіраторного синдрому свиней, вірус хвороби Ауєскі). Підтверджено також достатньо високу збіжність результатів. Загалом, отримані результати відповідають вимогам нормативно-технічної документації діагностикуму. Протестований діагностикум після проведення реєстрації буде рекомендований для використання у лабораторіях ветеринарної медицини
Nuclear shadowing at low Q^2
We re-examine the role of vector meson dominance in nuclear shadowing at low
Q^2. We find that models which incorporate both vector meson and partonic
mechanisms are consistent with both the magnitude and the Q^2 slope of the
shadowing data.Comment: 7 pages, 2 figures; to appear in Phys. Rev.
On the intersystem crossing rate in a Platinum(ii) donor–bridge–acceptor triad
The rates of ultrafast intersystem crossing in acceptor–bridge–donor molecules centered on Pt(II) acetylides are investigated. Specifically, a Pt(II) trans-acetylide triad NAP–[triple bond, length as m-dash]–Pt–[triple bond, length as m-dash]–Ph-CH2-PTZ [1], with acceptor 4-ethynyl-N-octyl-1,8-naphthalimide (NAP) and donor phenothiazine (PTZ), is examined in detail. We have previously shown that optical excitation in [1] leads to a manifold of singlet charge-transfer states, S*, which evolve via a triplet charge-transfer manifold into a triplet state 3NAP centered on the acceptor ligand and partly to a charge-separated state 3CSS (NAP−–Pt–PTZ+). A complex cascade of electron transfer processes was observed, but intersystem crossing (ISC) rates were not explicitly resolved due to lack of spin selectivity of most ultrafast spectroscopies. Here we revisit the question of ISC with a combination and complementary analysis of (i) transient absorption, (ii) ultrafast broadband fluorescence upconversion, FLUP, which is only sensitive to emissive states, and (iii) femtosecond stimulated Raman spectroscopy, FSR. Raman resonance conditions allow us to observe S* and 3NAP exclusively by FSR, through vibrations which are pertinent only to these two states. This combination of methods enabled us to extract the intersystem crossing rates that were not previously accessible. Multiple timescales (1.6 ps to ∼20 ps) are associated with the rise of triplet species, which can now be assigned conclusively to multiple ISC pathways from a manifold of hot charge-transfer singlet states. The analysis is consistent with previous transient infrared spectroscopy data. A similar rate of ISC, up to 20 ps, is observed in the trans-acetylide NAP–[triple bond, length as m-dash]–Pt–[triple bond, length as m-dash]–Ph [2] which maintains two acetylide groups across the platinum center but lacks a donor unit, whilst removal of one acetylide group in mono-acetylide NAP–[triple bond, length as m-dash]–Pt–Cl [3] leads to >10-fold deceleration of the intersystem crossing process. Our work provides insight on the intersystem crossing dynamics of the organo-metallic complexes, and identifies a general method based on complementary ultrafast spectroscopies to disentangle complex spin, electronic and vibrational processes following photoexcitation
Measurements of and production in proton–proton interactions at in the NA61/SHINE experiment
Double-differential yields of and
resonances produced in \pp interactions
were measured at a laboratory beam momentum of 158~\GeVc. This measurement is
the first of its kind in \pp interactions below LHC energies. It was performed
at the CERN SPS by the \NASixtyOne collaboration. Double-differential
distributions in rapidity and transverse momentum were obtained from a sample
of 2610 inelastic events. The spectra are extrapolated to full phase
space resulting in mean multiplicity of (6.73
0.25 0.67) and (2.71
0.18 0.18). The rapidity and transverse momentum
spectra and mean multiplicities were compared to predictions of string-hadronic
and statistical model calculations
Measurements of and production in proton–proton interactions at in the NA61/SHINE experiment
International audienceThe production of and hyperons in inelastic p+p interactions is studied in a fixed target experiment at a beam momentum of 158 . Double differential distributions in rapidity and transverse momentum are obtained from a sample of 33M inelastic events. They allow to extrapolate the spectra to full phase space and to determine the mean multiplicity of both and . The rapidity and transverse momentum spectra are compared to transport model predictions. The mean multiplicity in inelastic p+p interactions at 158 is used to quantify the strangeness enhancement in A+A collisions at the same centre-of-mass energy per nucleon pair
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