239 research outputs found
The subject of crime: the problem of establishing age limits of criminal responsibility
This article presents the authors’ analysis of the problem of determining the subject of a crime as a legal concept, and defining the legal characteristics of a person who has committed a crime by features that are necessary for criminal responsibility (individual, age, and responsibility
Effect of mechanical activation on the composition if mineral components in humic acids isolated from carbons
It is shown that the mechanical activation of oxidized and brown coals is accompanied by an increase in the yield of humic acids and in their content of functional groups. It was demonstrated by atomic-emission spectroscopy that, under a high-intensity mechanical treatment, mineral elements are redistributed in the coal substance and incorporated into the structure of humic acids
СОВЕРШЕНСТВОВАНИЕ ПРОЦЕДУРЫ ОПРЕДЕЛЕНИЯ БИС(2-ХЛОРЭТИЛ)СУЛЬФИДА В МАТЕРИАЛАХ С ВЫСОКОЙ СОРБЦИОННОЙ АКТИВНОСТЬЮ
A rapid, unified, highly sensitive and selective procedure for bis(2-chloroethyl)sulfide (sulfur mustard, SM) determination in matrices with high sorption activity using gas chromatography-tandem mass-spectrometry (GC-MS/MS) was developed. Ceramic tile, concrete, various types of bricks and polymers were studied as objects of the analysis. The parameters for the GC-MS/MS determination of SM were optimized. The efficiency of five solvents (diethyl ether, 2-chloropropane, acetonitrile, hexane, and acetone) for the extraction of SM from the various matrices was studied. 2-chloropropane was the extraction solvent of choice. The developed procedure is based on the extraction of SM from the matrix and the concentration of the extract under the stream of nitrogen to 0.2 mL followed by GC-MS/MS analysis. The LODs for SM in all investigated matrices were 0.7-0.9 ng/g (0.007-0.009 MPC). The long-term stability of SM in various materials was studied. It was shown that in brick, concrete and ceramic samples the residual amount of SM after five months of storage at 4°C was below the LOD of the method, while in polymer samples under the same storage condition the amount of SM has not changed significantly. The developed procedure has been applied to the analysis of samples from the former chemical weapons destruction facility.Key words: bis(2-chloroethyl)sulfide, sulfur mustard, construction materials, gas chromatography, tandem mass-spectrometryDOI: http://dx.doi.org/10.15826/analitika.2021.25.2.004 M.D. Shachneva, N.L. Koryagina, E.I. Savelieva Research Institute of Hygiene, Occupational Pathology and Human EcologyFederal State Unitary Enterprise, Federal Medical Biological Agency,g/p Kuz’molovsky, Vsevolozhsky District, Leningrad Region, 188663, Russian FederationРазработана унифицированная высокочувствительная высокоселективная и экспрессная процедура определения бис(2-хлорэтил)сульфида (сернистого иприта) в образцах с высокой сорбционной активностью методом газовой хроматографии с тандемным масс-селективным детектированием (ГХ-МС/МС). Процедура основана на экстракции бис(2-хлорэтил)сульфида из матрицы и концентрировании экстракта в токе азота до 0.2 мл с последующим анализом методом ГХ-МС/МС. В качестве объектов анализа исследованы керамическая плитка, бетон, различные виды кирпича и полимеров. Предел определения иприта в разных матрицах составил 0.7-0.9 нг/г (0.007-0.009 ПДК). Изучена эффективность пяти экстрагентов (диэтилового эфира, 2-хлорпропана, ацетонитрила, гексана и ацетона) для извлечения аналита из матриц различной природы. Показано, что для извлечения бис(2-хлорэтил)сульфида из впитывающих материалов оптимальным экстрагентом является 2-хлорпропан. Исследована стабильность бис(2-хлорэтил)сульфида в составе впитывающих материалов в процессе длительного хранения. Показано, что в образцах на основе бетона после пяти месяцев хранения при температуре 4 °С остаточное содержание бис(2-хлорэтил)сульфида ниже предела обнаружения методики, в то время как в полимерных материалах в этих же условиях хранения содержание бис(2-хлорэтил)сульфида практически не менялось. Проведена апробация методики на образцах строительных материалов, отобранных при мониторинге бывшего объекта по уничтожению химического оружия на этапе конверсии.Ключевые слова: бис(2-хлорэтил)сульфид, сернистый иприт, строительные материалы, газовая хроматография, тандемное масс-селективное детектированиеDOI: http://dx.doi.org/10.15826/analitika.2021.25.2.00
Electrochemical Aptasensor Based on a Macrocyclic Ligand Bearing Neutral Red
An amperometric aptasensor has been developed by immobilization of DNA aptamer with Neutral Red (NR) on polycarboxylated thiacalix[4]arene onto the electropolymerized NR layer at a glassy carbon electrode. The NR reduction current recorded after 10min incubation decayed with increased thrombin concentration due to limitation of the electron exchange in the surface layer. The aptasensor makes it possible to determine 0.1-50nM of thrombin (limit of detection 0.05nM). The aptasensor can be used for the direct determination of thrombin in blood serum and does not exert any alteration of the response in the presence of 100 fold excess of serum proteins. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Label-free aptasensor for thrombin determination based on the nanostructured phenazine mediator
New aptasensors based on DNA aptamer and polycarboxylated thiacalix[4]arenes in cone, 1,3-alternate and partial cone configurations bearing Neutral Red (NR) at substituents at the lower rim have been developed and applied for thrombin detection. The assembly of the biorecognition layer was optimized by AFM and EIS study to reach the maximal coverage and regular composition of the surface layer. The interaction of the NR groups with thrombin suppressed the electron hopping between oxidized and reduced mediator groups. This regularly decreased the NR peak current and increased the resistance of the charge transfer. The aptasensor makes it possible to detect from 1 nM to 1 μM of thrombin with the detection limit of 0.05-0.5 nM. No effect of the 1000 excess of bovine serum albumin on the signal was observed. The influence of thiacalix[4]arene configuration on the sensitivity of aptasensor signal toward thrombin is discussed. © 2012 Elsevier B.V. All rights reserved
HL-1 cells express an inwardly rectifying K+ current activated via muscarinic receptors comparable to that in mouse atrial myocytes
An inwardly rectifying K^+ current is present in atrial cardiac myocytes that is activated by acetylcholine (I_{KACh}). Physiologically, activation of the current in the SA node is important in slowing the heart rate with increased parasympathetic tone. It is a paradigm for the direct regulation of signaling effectors by the Gβγ G-protein subunit. Many questions have been addressed in heterologous expression systems with less focus on the behaviour in native myocytes partly because of the technical difficulties in undertaking comparable studies in native cells. In this study, we characterise a potassium current in the atrial-derived cell line HL-1. Using an electrophysiological approach, we compare the characteristics of the potassium current with those in native atrial cells and in a HEK cell line expressing the cloned Kir3.1/3.4 channel. The potassium current recorded in HL-1 is inwardly rectifying and activated by the muscarinic agonist carbachol. Carbachol-activated currents were inhibited by pertussis toxin and tertiapin-Q. The basal current was time-dependently increased when GTP was substituted in the patch-clamp pipette by the non-hydrolysable analogue GTPγS. We compared the kinetics of current modulation in HL-1 with those of freshly isolated atrial mouse cardiomyocytes. The current activation and deactivation kinetics in HL-1 cells are comparable to those measured in atrial cardiomyocytes. Using immunofluorescence, we found GIRK4 at the membrane in HL-1 cells. Real-time RT-PCR confirms the presence of mRNA for the main G-protein subunits, as well as for M2 muscarinic and A1 adenosine receptors. The data suggest HL-1 cells are a good model to study IKAch
Thermal chamber for material testing
© Published under licence by IOP Publishing Ltd. The problem of ensuring the correct conduct of the experiment with preservation of the required temperature is considered. The construction of the device is proposed that will allow satisfying the conditions for carrying out tensile tests with an increased or lowered sample temperature
Improvement of the procedure for bis(2-chloroethyl)sulfide determination in matrices with high sorption activity
Разработана унифицированная высокочувствительная высокоселективная и экспрессная процедура определения бис(2-хлорэтил)сульфида (сернистого иприта) в образцах с высокой сорбционной активностью методом газовой хроматографии с тандемным масс-селективным детектированием (ГХ-МС/МС). Процедура основана на экстракции бис(2-хлорэтил)сульфида из матрицы и концентрировании экстракта в токе азота до 0.2 мл с последующим анализом методом ГХ-МС/МС. В качестве объектов анализа исследованы керамическая плитка, бетон, различные виды кирпича и полимеров. Предел определения иприта в разных матрицах составил 0.7-0.9 нг/г (0.007-0.009 ПДК). Изучена эффективность пяти экстрагентов (диэтилового эфира, 2-хлорпропана, ацетонитрила, гексана и ацетона) для извлечения аналита из матриц различной природы. Показано, что для извлечения бис(2-хлорэтил)сульфида из впитывающих материалов оптимальным экстрагентом является 2-хлорпропан. Исследована стабильность бис(2-хлорэтил)сульфида в составе впитывающих материалов в процессе длительного хранения. Показано, что в образцах на основе бетона после пяти месяцев хранения при температуре 4 °С остаточное содержание бис(2-хлорэтил)сульфида ниже предела обнаружения методики, в то время как в полимерных материалах в этих же условиях хранения содержание бис(2-хлорэтил)сульфида практически не менялось. Проведена апробация методики на образцах строительных материалов, отобранных при мониторинге бывшего объекта по уничтожению химического оружия на этапе конверсии.A rapid, unified, highly sensitive and selective procedure for bis(2-chloroethyl)sulfide (sulfur mustard, SM) determination in matrices with high sorption activity using gas chromatography-tandem mass-spectrometry (GC-MS/MS) was developed. Ceramic tile, concrete, various types of bricks and polymers were studied as objects of the analysis. The parameters for the GC-MS/MS determination of SM were optimized. The efficiency of five solvents (diethyl ether, 2-chloropropane, acetonitrile, hexane, and acetone) for the extraction of SM from the various matrices was studied. 2-chloropropane was the extraction solvent of choice. The developed procedure is based on the extraction of SM from the matrix and the concentration of the extract under the stream of nitrogen to 0.2 mL followed by GC-MS/MS analysis. The LODs for SM in all investigated matrices were 0.7-0.9 ng/g (0.007-0.009 MPC). The long-term stability of SM in various materials was studied. It was shown that in brick, concrete and ceramic samples the residual amount of SM after five months of storage at 4°C was below the LOD of the method, while in polymer samples under the same storage condition the amount of SM has not changed significantly. The developed procedure has been applied to the analysis of samples from the former chemical weapons destruction facility
Medium and long-term adherence to postabortion contraception among women having experienced unsafe abortion in Dar es Salaam, Tanzania
<p>Abstract</p> <p>Background</p> <p>Postabortion contraceptive service is considered an effective means in addressing the problem of unsafe abortion; in spite this fact this component remains one of the weakest parts of postabortion care. In this context, the paper aims to describe the impact of a postabortion contraceptive service intervention among women admitted with complications from unsafe abortions and to explore the women's long-term contraceptive adherence.</p> <p>Methods</p> <p>392 women having experienced unsafe abortion were identified by an empathetic approach and offered postabortion contraceptive service, which included counselling on HIV and condom use. Questionnaire interviews about contraceptive use were conducted at the time of inclusion and 12 months after the abortion. Additionally, in-depth interviews were performed 6–12 months after the abortion.</p> <p>Results</p> <p>Eighty-nine percent of the women accepted postabortion contraception. Follow-up information was obtained 12 months after the abortion among 59 percent of the women. Among these, 79 percent of the married women and 84 percent of the single women stated they were using contraception at 12 months. Condom use among the single women increased significantly during the 12 months follow up.</p> <p>Conclusion</p> <p>Postabortion contraceptive services appear to be well accepted by women who are admitted with complications after an unsafe abortion and should thus be recognized as an important means in addressing the problem of unsafe abortion. In addition, counselling about HIV and condom use should be considered an essential aspect of postabortion care.</p
- …