44 research outputs found

    МЕТОДИКА ОПРЕДЕЛЕНИЯ ИЗОТОПНЫХ ОТНОШЕНИЙ Cu И Zn МЕТОДОМ МК ИСП-МС С ИСПОЛЬЗОВАНИЕМ СМОЛЫ AG MP-1

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    The isotopic composition of copper is of great interest for researchers in various fields of science, geochemistry and hydrology in particular, wherein the consideration is being given to the variations in the isotopic composition of the Earth's crust, extraterrestrial matter, and water basins, as well as to the origin and transfer of matter. Zn isotopes appear to be promising for identifying the sources and pathways of the environmental pollution. The aim of this study involves the refinement and validation of the zinc and copper isotopic ratio determination methodology covering the whole process from sample digestion to MC ICP-MS measurements. For this reason, as well as to assess the suitability of the methodology for the analysis of environmental samples, Zn and Cu isotopic analysis of the BHVO-2, BCR-2 and AGV2 USGS certified reference materials has been performed. The method for determination of Cu and Zn stable isotope ratios by multi-collector inductively coupled plasma mass spectrometry in environmental samples is developed. The application of the AG MP1 resin with optimized layer parameters (resin bed height 3.5 cm, diameter 1 cm) provides the highpurity Cu and Zn fractions. The method is characterized by high throughput and adequate analytical figures of merit when using the standardsample bracketing technique for mass bias correction. The procedural blanks related to chemical dissolution and ion exchange procedures are lower than 1 and 3 ng for Cu and Zn, respectively, assuring no blank effect on the isotopic composition of samples. The accuracy and precision obtained for Cu and Zn isotope measurements in the BHVO2, BCR2 and AGV2 geological certified reference materials demonstrate good agreement with the reference values published. © 2022 Institute of the Earth's Crust. All rights reserved.ААААА181180530900458; Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-15-2021-680; Russian Science Foundation, RSF: 18-77-10024The work of Okuneva T.G. is supported by the Russian Science Foundation (project 18-77-10024), the rest authors are supported by the state assignment of the IGG UB RAS ААААА181180530900458. Isotopic analyses are performed at the "Geoanalitik" Shared Research Facilities of the IGG UB RAS. The reequipment and comprehensive development of the "Geoanalitik" Shared Research Facilities of the IGG UB RAS is financially supported by the grant of the Ministry of Science and Higher Education of the Russian Federation (Agreement 075-15-2021-680).authors are supported by the state assignment of the IGG UB RAS ААААА 猃?猃猃稃爃眃甃爃笃爃爃瘃?稁 Isotopic analyses are performed at the 㘀Geoanalitik ? Shared Research Facilities of the IGG UB RAS. The reequipment and comprehensive development of the 㘀Geoanalitik 㘀 Shared Research Facilities of the IGG UB RAS is 퀀inancially supported by the grant of the Ministry of Science and Higher Education of the Russian Federation (Agreement 075-15-2021-680).FUNDING: The work of Okuneva T.G. is supported by the Russian Science Foundation (project 18-77-10024), the res

    THE METHOD FOR Cu AND Zn ISOTOPE RATIO DETERMINATION BY MC ICP-MS USING THE AG MP-1 RESIN

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    The isotopic composition of copper is of great interest for researchers in various fields of science, geochemistry and hydrology in particular, wherein the consideration is being given to the variations in the isotopic composition of the Earth’s crust, extraterrestrial matter, and water basins, as well as to the origin and transfer of matter. Zn isotopes appear to be promising for identifying the sources and pathways of the environmental pollution. The aim of this study involves the refinement and validation of the zinc and copper isotopic ratio determination methodology covering the whole process from sample digestion to MC ICP-MS measurements. For this reason, as well as to assess the suitability of the methodology for the analysis of environmental samples, Zn and Cu isotopic analysis of the BHVO-2, BCR-2 and AGV-2 USGS certified reference materials has been performed. The method for determination of Cu and Zn stable isotope ratios by multi-collector inductively coupled plasma mass spectrometry in environmental samples is developed. The application of the AG MP-1 resin with optimized layer parameters (resin bed height 3.5 cm, diameter 1 cm) provides the high-purity Cu and Zn fractions. The method is characterized by high throughput and adequate analytical figures of merit when using the standard-sample bracketing technique for mass bias correction. The procedural blanks related to chemical dissolution and ion exchange procedures are lower than 1 and 3 ng for Cu and Zn, respectively, assuring no blank effect on the isotopic composition of samples. The accuracy and precision obtained for Cu and Zn isotope measurements in the BHVO-2, BCR-2 and AGV-2 geological certified reference materials demonstrate good agreement with the reference values published

    Temperature Evolution of Sodium Nitrite Structure in a Restricted Geometry

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    The NaNO2_{2} nanocomposite ferroelectric material in porous glass was studied by neutron diffraction. For the first time the details of the crystal structure including positions and anisotropic thermal parameters were determined for the solid material, embedded in a porous matrix, in ferro- and paraelectric phases. It is demonstrated that in the ferroelectric phase the structure is consistent with bulk data but above transition temperature the giant growth of amplitudes of thermal vibrations is observed, resulting in the formation of a "premelted state". Such a conclusion is in a good agreement with the results of dielectric measurements published earlier.Comment: 4 pages, 4 figure

    АТОПИЧЕСКИЙ ДЕРМАТИТ У ДЕТЕЙ: НАЛИЧИЕ СПЕЦИФИЧЕСКИХ АНТИТЕЛ К СУПЕРАНТИГЕНАМ STAPHYLOCOCCUS AUREUS И ЕГО АНТИБИОТИКОРЕЗИСТЕНТНОСТЬ

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    Background. Staphylococcus aureus function in atopic dermatitis (AD) children skin is double-handed: an infectious trigger and an allergen. The aim of the study was to evaluate the frequency of S. aureus enterotoxins the IgE in children with infected AD skin and to compare the IgE levels with antibiotic resistance of S. aureus. Methods: specific IgE to S. aureus enterotoxins A and B (ImmunoCap, Phadia AB, Sweden) were detected in the serum of 90 children infected with AD. The IgE levels were compared with the resistance to antibiotics (McNemar test and 95% confidential intervals of related frequencies). Results: specific IgE > 0,35 kUA/l to S. aureus enterotoxin A were found with a frequency of 0,29; to enterotoxin B — 0,36; to at least one of them — 0,43. The number of children with IgE > 0,35 kUA/l and S. aureus resistant to antibiotics was about 1/3 of the number of children with IgE < 0,35 kUA/l and S. aureus sensitive to antibiotics (р < 0,001). S. aureus in children with IgE > 0,35 kUA/l remained sensitive to oxacillin. Conclusion. In children infected with AD S. aureus enterotoxins A or/and B are revealed in 25–50% of cases. Specific IgE levels to S. aureus enterotoxins are similar in antibiotic resistant and antibiotic sensitive S. aureus skin swabs — about 30%. The IgE level to enterotoxins of S. aureus and its antibiotic resistance don't seem to be conditioned by each other.Актуальность. Наличие атопии создает условия для функционирования Staphylococcus aureus не только в качестве триггера инфекционного процесса, но и в качестве аллергена. Цель работы — оценить частоту выявления специфических IgE к энтеротоксинам S. aureus кожи детей с атопическим дерматитом (АтД), осложненным вторичным инфицированием кожи, и сопоставить наличие IgE с антибиотикорезистентностью S. aureus. Пациенты и методы. Обследовано 90 детей с АтД, осложненным вторичным инфицированием кожи. Специфические IgE-антитела к энтеротоксинам А и В  S. aureus определяли иммунохемилюминесцентным методом (ImmunoCap, Phadia AB, Швеция). Оценивали взаимосвязь наличия IgE к энтеротоксинам S. aureus с его антибиотикорезистентностью (критерий МакНемара, 95% доверительные интервалы относительных частот). Результаты. Специфические IgE к энтеротоксину А обнаружены с частотой 0,29, к энтеротоксину В — 0,36, хотя бы к одному из них — 0,43. Количество детей с наличием специфических IgE и устойчивыми к антибиотикам штаммами S. aureus составляло 1/3 количества детей с отсутствием IgE и чувствительными штаммами S. aureus (р < 0,001). Заключение. У детей с АтД, осложненным вторичной инфекцией, энтеротоксины А и/или В S. aureus обнаруживаются в 25–50% наблюдений. Частота выявления IgE к энтеротоксинам S. aureus одинакова у штаммов с различной антибиотикорезистентностью и составляет 30%. Взаимной опосредованности антибиотикорезистентности S. aureus и выработки специфических IgE-антител к его энтеротоксинам не выявлено

    Определение фоновых изотопных отношений биодоступного стронция для рудника бронзового века новотемирский

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    To assess the mobility and provenance of ancient populations, it is necessary to compare their 87Sr/86Sr isotopic ratios with the local bioavailable strontium baseline (background), characteristic of each specific location or potential provenance region of an individual or artifact. Its definition requires a comprehensive approach to the analysis of heterogeneous samples («proxies») characterizing the ecosystem of the archaeological site under study, the identification of the most suitable proxies, as well as the unification and standardization of the sampling and analytic protocols. A pilot study is presented devoted the definition of the local range of bioavailable strontium by the example of the Novotemirskiy Bronze Age mine (Southern Urals). 87Sr/86Sr isotope ratios were determined in surface and underground water, bedrock (serpentinite), clay from the mine wall, and steppe polecat’s bone, as well as in grass and a bivalve shell from the lake. The lowest range of strontium isotope ratios relative to each other is characteristic of surface and groundwater, shell and grass, which allows them to be used to determine the combined baseline of bioavailable strontium. Multi-proxy (surface and underground water, grass and a bivalve shell) local bioavailable strontium baseline for the Novotemirskiy ancient mine (Southern Urals) is 0,7096 ± 0,0003 (2σ, n = 5). © 2021 Russian Academy of Sciences, Institute of Archaeology. All rights reserved.Работа выполнена при финансовой поддержке РНФ, проект No 20-18-00402 «Миграции человеческих коллективов и индивидуальная мобильность в рамках мультидисциплинарного анализа археологической информации (бронзовый век Южного Урала)», в ЮУрГУ (НИУ) (Д. В. Киселева – геохимическая интерпретация, П. С. Анкушева – археологическая документация и аналитика; Т. Г. Окунева, А. В. Касьянова – измерения проб и стандартных образцов; Е. С. Шагалов, М. Н. Анкушев – отбор проб и геологическая характеристика)

    Fungal endophthalmitis

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    The article presents a clinical case of fungal endophthalmitis, the causative agent of which was Paecilomyces lilacinum. Patient M., female, 1947 year of birth was operated on for complicated cataract of the right eye. Two weeks later, she complained of decreased vision. A local anti-inflammatory therapy of the exudative reaction in the anterior chamber was carried out, therefore an improvement was achieved. Two weeks later, the patient again complained of visual impairment. Лечение было продолжено со сменой фунгицидных средств, обладающих большим Systemic and local anti-inflammatory and antibacterial therapy of exudative uveitis with the course of fluconazole for 15 days was carried out. Extended clinical and laboratory studies did not reveal any chronic inflammatory and immune diseases in the female patient. In connection with the further progression of the process, vitrectomy was performed with the removal of IOL and washing of the vitreous cavity with a solution of vancomycin. The achieved stabilization lasted short. There were appeared signs indicating a fungal etiology of the inflammatory process. Taking into account the previous long-term antibiotic therapy, yeast contamination was suggested. Despite the active treatment, there was a further deterioration of the eye. No pathogenic and conditionally pathogenic microflora growth was revealed as a result of seeding. Confocal microscopy revealed a filamentous structure of the mycelium in the thickness of the corneal stroma, which indicated infection with mold, not yeast fungi. Treatment was continued with a change of fungicidal agents with a large spectrum of action, as well as a silicone oil tamponade. The obtained culture was aimed at identification of the species and determination of sensitivity to fungicides in the medical scientific and practical center for tuberculosis control, Moscow. Cultural studies identified pathogenic microflora – Paecilomyces lilacinum, sensitive to ketoconazole. In connection with the spread of infection to the periorbital tissues, with the subsequent probability of systemic damage, an emergency enucleation of the eyeball was decided. This example indicates the need for increased alertness for fungal infection in cases of atypical flow of intraocular inflammation, the search for methods for early detection of the pathogen

    МЕТОДИКА ОПРЕДЕЛЕНИЯ ИЗОТОПНЫХ ОТНОШЕНИЙ Cu И Zn МЕТОДОМ МК ИСП-МС С ИСПОЛЬЗОВАНИЕМ СМОЛЫ AG MP-1

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    The isotopic composition of copper is of great interest for researchers in various fields of science, geochemistry and hydrology in particular, wherein the consideration is being given to the variations in the isotopic composition of the Earth’s crust, extraterrestrial matter, and water basins, as well as to the origin and transfer of matter. Zn isotopes appear to be promising for identifying the sources and pathways of the environmental pollution. The aim of this study involves the refinement and validation of the zinc and copper isotopic ratio determination methodology covering the whole process from sample digestion to MC ICP-MS measurements. For this reason, as well as to assess the suitability of the methodology for the analysis of environmental samples, Zn and Cu isotopic analysis of the BHVO-2, BCR-2 and AGV-2 USGS certified reference materials has been performed. The method for determination of Cu and Zn stable isotope ratios by multi-collector inductively coupled plasma mass spectrometry in environmental samples is developed. The application of the AG MP-1 resin with optimized layer parameters (resin bed height 3.5 cm, diameter 1 cm) provides the high-purity Cu and Zn fractions. The method is characterized by high throughput and adequate analytical figures of merit when using the standard-sample bracketing technique for mass bias correction. The procedural blanks related to chemical dissolution and ion exchange procedures are lower than 1 and 3 ng for Cu and Zn, respectively, assuring no blank effect on the isotopic composition of samples. The accuracy and precision obtained for Cu and Zn isotope measurements in the BHVO-2, BCR-2 and AGV-2 geological certified reference materials demonstrate good agreement with the reference values published.Изотопный состав меди представляет большой интерес для исследователей в различных областях науки, в частности в геохимии и гидрологии, где рассматриваются вариации изотопного состава земной коры и внеземного вещества, водных бассейнов, а также вопросы происхождения и процессы переноса вещества. Изотопы Zn перспективны для определения источников и путей загрязнения окружающей среды. Целью данного исследования является уточнение и валидация методики измерения изотопных соотношений цинка и меди, охватывающей весь процесс – от разложения образца до измерений методом МК ИСП-МС. Для оценки пригодности методики анализа образцов окружающей среды был проведен изотопный анализ Zn и Cu в стандартных образцах BHVO-2, BCR-2 и AGV-2, сертифицированных Геологический службой США. Разработан метод определения отношений стабильных изотопов Cu и Zn с помощью мультиколлекторной масс-спектрометрии с индуктивно связанной плазмой в экологических пробах. Применение смолы AG MP-1 с оптимизированными параметрами слоя (высота слоя смолы 3.5 см, диаметр 1 см) обеспечивает получение фракций Cu и Zn высокой чистоты. Метод отличается высокой производительностью и удовлетворительными метрологическими характеристиками при использовании брекетинга для коррекции дискриминации ионов по массе. Процедурные бланки (холостые пробы), относящиеся к процедурам химического растворения и хроматографии, составляют менее 1 нг для Cu и 3 нг для Zn, что гарантирует отсутствие значимого влияния холостой (контрольной) пробы на изотопный состав образцов. Точность и прецизионность, полученные при измерениях изотопов Cu и Zn в сертифицированных геологических стандартных материалах BHVO-2, BCR-2 и AGV-2, демонстрируют хорошее согласие с опубликованными сертифицированными значениями

    УБМ-критерии безопасности фемтосопровождения в хирургии катаракты после ранее выполненной микроинвазивной непроникающей глубокой склерэктомии

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    PURPOSE: To evaluate the safety criteria of femtolaser impact during femtosecond laser–assisted cataract phacoemulsification on the filtration zone after microinvasive non-penetrating deep sclerotomy based on ultrasound bio- microscopy data.MATERIALS AND METHODS: 12 patients (15 eyes) with operated primary open-angle glaucoma, 7 women and 5 men, were kept under observation. The average age of the patients was 64±11 years. Femtosecond laser–assisted cataract phacoemulsification was performed 6-12 months after microinvasive non-penetrating deep sclerectomy. In addition to standard research methods all patients underwent ultrasound biomicroscopy prior to surgery. The femtolaser stage of the surgery was performed using FEMTO LDV Z8 device («Ziemer», Switzerland). Ultrasonic cataract phacoemulsification was performed using Centurion VisionSystem («Alcon», USA) according to the standard phaco-chop technique. Ultrasonic biomicroscopy follow-up was performed 1 day and 1 month after the operation.RESULTS: Study results indicate the need to include ultrasound biomicroscopy into the list of mandatory diag nostic research methods for patients with previously operated glaucoma prior to femtosecond laser–assisted cataract surgery. To ensure a safe performing of femtolaser cataract surgery in patients after microinvasive non-penetrating deep sclerectomy, one has to take into account a combination of such features as the preservation of the linear profile of the trabeculodecemetic membrane, the absence of its dense adhesions with surrounding tissues, and the presence of an intrascleral cavity with a height of 0.25 mm and above. Failure to respect these conditions when using femtosecond laser technology can lead to adverse changes of the newly formed drainage system.CONCLUSION: Femtosecond laser–assisted cataract surgery for patients who previously underwent microinvasive non-penetrating deep sclerotomy (MNSE) is a safe and effective technology when performed after a preliminary selection of patients based on filtration zone ultrasound biomicroscopy (UBM).ЦЕЛЬ: Выявить критерии безопасности фемтолазерного воздействия на фильтрационную зону в ходе факоэмульсификации катаракты (ФЭК) после микроинвазивной непроникающей глубокой склерэктомии (МНГСЭ) на основании данных ультразвуковой биомикроскопии (УБМ). МАТЕРИАЛЫ И МЕТОДЫ. Под наблюдением находились 12 пациентов (7 женщин, 5 мужчин; 15 глаз) с оперированной первичной открытоугольной глаукомой. Средний возраст пациентов составил 64±11 лет. ФЭК с фемтолазерным сопровождением выполнялась через 6-12 месяцев после ранее проведенной МНГСЭ. В предоперационном периоде помимо стандартных методов исследования всем пациентам дополнительно проводили УБМ. Фемтолазерный этап операции выполняли на приборе FEMTO LDV Z8 («Ziemer», Швейцария). Ультразвуковую ФЭК проводили на системе Centurion VisionSystem («Alcon», США) по стандартной методике «phaco-chop». УБМ в динамике осуществляли в 1-е сутки и через 1 месяц после операции.РЕЗУЛЬТАТЫ.Результаты исследования указывают на необходимость включения ультразвуковой биомикроскопии в перечень обязательных методов исследования для пациентов с ранее оперированной глаукомой на этапе диагностики перед хирургией катаракты с фемтосопровождением. Для обеспечения безопасного проведения фемтолазерной хирургии катаракты у пациентов после МНГСЭ следует учитывать совокупность таких признаков, как сохранность линейного профиля трабекулодесцеметовой мембраны, отсутствие ее плотных сращений с окружающими тканями, наличие интрасклеральной полости с высотой от 0,25 мм и выше. Применение фемтолазерной технологии при несоблюдении данных условий может спровоцировать неблагоприятные изменения в сформированной дренажной системе. ЗАКЛЮЧЕНИЕ. Фемтолазерная хирургия катаракты, выполняемая при наличии показаний и на основе предварительного отбора пациентов с учетом данных УБМ фильтрационной зоны после МНГСЭ, является безопасной и эффективной технологией у пациентов с оперированной ранее глаукомой

    Primary Cosmic Rays Energy Spectrum and Mean Mass Composition by the Data of the TAIGA Astrophysical Complex

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    The corrected dependence of the mean depth of the EAS maximum XmaxX_{max} on the energy was obtained from the data of the Tunka-133 array for 7 years and the TAIGA-HiSCORE array for 2 year. The parameter lnA\langle\ln A\rangle, characterizing the mean mass compositon was derived from these results. The differential energy spectrum of primary cosmic rays in the energy range of 210142\cdot 10^{14} - 210162\cdot 10^{16}\,eV was reconstructed using the new parameter Q100Q_{100} the Cherenkov light flux at the core distance 100 m.}Comment: 6 pages, 3 figures, Submitted to SciPost Phys.Pro
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