130 research outputs found
Driving magnetic order in a manganite by ultrafast lattice excitation
Optical control of magnetism, of interest for high-speed data processing and
storage, has only been demonstrated with near-infrared excitation to date.
However, in absorbing materials, such high photon energies can lead to
significant dissipation, making switch back times long and miniaturization
challenging. In manganites, magnetism is directly coupled to the lattice, as
evidenced by the response to external and chemical pressure, or to
ferroelectric polarization. Here, femtosecond mid-infrared pulses are used to
excite the lattice in La0.5Sr1.5MnO4 and the dynamics of electronic order are
measured by femtosecond resonant soft x-ray scattering with an x-ray free
electron laser. We observe that magnetic and orbital orders are reduced by
excitation of the lattice. This process, which occurs within few picoseconds,
is interpreted as relaxation of the complex charge-orbital-spin structure
following a displacive exchange quench - a prompt shift in the equilibrium
value of the magnetic and orbital order parameters after the lattice has been
distorted. A microscopic picture of the underlying unidirectional lattice
displacement is proposed, based on nonlinear rectification of the
directly-excited vibrational field, as analyzed in the specific lattice
symmetry of La0.5Sr1.5MnO4. Control of magnetism through ultrafast lattice
excitation has important analogies to the multiferroic effect and may serve as
a new paradigm for high-speed optomagnetism.Comment: 10 pages manuscript, 4 figure
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Gender differences in the pharmacological actions of pegylated glucagon-Like peptide-1 on endothelial progenitor cells and angiogenic precursor cells in a combination of metabolic disorders and lung emphysema
In clinical practice, the metabolic syndrome (MetS) is often associated with chronic obstructive pulmonary disease (COPD). Although gender differences in MetS are well documented, little is known about sex-specific differences in the pathogenesis of COPD, especially when combined with MetS. Consequently, it is not clear whether the same treatment regime has comparable efficacy in men and women diagnosed with MetS and COPD. In the present study, using sodium glutamate, lipopolysaccharide, and cigarette smoke extract, we simulated lipid metabolism disorders, obesity, hyperglycemia, and pulmonary emphysema (comorbidity) in male and female C57BL/6 mice. We assessed the gender-specific impact of lipid metabolism disorders and pulmonary emphysema on angiogenic precursor cells (endothelial progenitor cells (EPC), pericytes, vascular smooth muscle cells, cells of the lumen of the nascent vessel), as well as the biological effects of pegylated glucagon-like peptide 1 (pegGLP-1) in this experimental paradigm. Simulation of MetS/COPD comorbidity caused an accumulation of EPC (CD45−CD31+CD34+), pericytes, and vascular smooth muscle cells in the lungs of female mice. In contrast, the number of cells involved in the angiogenesis decreased in the lungs of male animals. PegGLP-1 had a positive effect on lipids and area under the curve (AUC), obesity, and prevented the development of pulmonary emphysema. The severity of these effects was stronger in males than in females. Furthermore, PegGLP-1 stimulated regeneration of pulmonary endothelium. At the same time, PegGLP-1 administration caused a mobilization of EPC (CD45−CD31+CD34+) into the bloodstream in females and migration of precursors of angiogenesis and vascular smooth muscle cells to the lungs in male animals. Gender differences in stimulatory action of pegGLP-1 on CD31+ endothelial lung cells in vitro were not observed. Based on these findings, we postulated that the cellular mechanism of in vivo regeneration of lung epithelium was at least partly gender-specific. Thus, we concluded that a pegGLP-1-based treatment regime for metabolic disorder and COPD should be further developed primarily for male patients
КАЧЕСТВО ЖИЗНИ ПАЦИЕНТОВ С МЫШЕЧНО-ИНВАЗИВНЫМ РАКОМ МОЧЕВОГО ПУЗЫРЯ СТАДИИ Т2B−Т3А ПОСЛЕ ХИРУРГИЧЕСКОГО ЛЕЧЕНИЯ
The article represents the study of quality of life in patients with muscle-invasive bladder cancer stages T2b and T3a after surgery, depending on the operation type. The study was conducted using questionnaires EORTC QLQ-30 and FACT-BL. The best levels of quality of life were observed in patients after organ-saving treatment of muscle-invasive bladder cancer.Представлен материал по изучению качества жизни у пациентов с мышечно-инвазивным раком мочевого пузыря (РМП) стадии Т2b и Т3а после хирургического лечения в зависимости от вида оперативного пособия. Исследование проводилось с помощью опросников EORTC QLQ-30 и FACT-BL. Наилучшие показатели качества жизни наблюдаются среди пациентов после органосохраняющего лечения мышечно-инвазивного РМП
ХАРАКТЕР РЕЦИДИВИРОВАНИЯ ПОСЛЕ ОРГАНОСОХРАНЯЮЩЕГО ОПЕРАТИВНОГО ЛЕЧЕНИЯ МЫШЕЧНО-ИНВАЗИВНОГО РАКА МОЧЕВОГО ПУЗЫРЯ
The article represents the study of frequency and nature of the recurrence and survival rate (common, oncology-specific, disease-free) after organ-saving surgery of patients with muscle-invasive bladder cancer stages T2b and T3a. Oncology-speсific and disease-free survival rates were much higher if full diagnosis of bladder mucosa, the adjuvant intravesical chemotherapy had been on pre-operative and intra-operative stages than in the absence of these diagnosis and therapy. Recurrentes of bladder cancer which appeared in the absence of diagnosis and combination therapy, statistically reliably occured at another location other than the zone of operation, stage of recurrentes and degree of differentiation of recurrents were less than the original tumor. This information confirms the existence of foci of cancer in situ which have not been identified on the diagnostic stage.Изучены частота, характер рецидивирования и показатели выживаемости (общей, онкоспецифической, безрецидивной) после органосохраняющего оперативного лечения мышечно-инвазивного рака мочевого пузыря (РМП) в стадии Т2b−Т3а. Выявлено, что онкоспецифическая и безрецидивная выживаемость при наличии полноценной диагностики слизистой мочевого пузыря на до- и интраоперационном этапах и при проведении адъювантной внутрипузырной химиотерапии намного выше, чем при отсутствии данных обследований и комбинированной терапии. Рецидивы РМП, возникающие при отсутствии обследования слизистой мочевого пузыря и адъювантной внутрипузырной химиотерапии, статистически достоверно возникают на другом месте, отличном от зоны операции, стадия рецидива и степень дифференцировки рецидива меньше, чем первоначальной опухоли, что подтверждает наличие очагов рака in situ, не выявленных на этапе диагностики
Development of a technology for the preparation of a dry nutrient medium for anthrax vaccine production
Currently, submerged cultivation of the Bacillus anthracis STI-1 strain for live anthrax vaccine production requires liquid nutrient media, which have disadvantages of a short shelf life (no more than one month) and a narrow range of storage temperatures (2–8 °С). Dry media, in contrast, have a number of indisputable advantages: such media are transportable and easy to use, have a standard capability to retain properties, and can be stored without preservatives at 2–30 °С for 2–5 years. The aim of this work was to develop a technology for the preparation of a dry nutrient medium for anthrax vaccine production. Materials and methods: The study used the Bacillus anthracis STI-1 vaccine strain and a nutrient medium for its cultivation, containing a 70:30 mixture of an enzymatic digest of casein and a pre-processed corn extract solution. Drying of the nutrient medium was carried out on a spray-drying unit. The authors evaluated physicochemical parameters of experimental medium batches. The shelf life was determined by an accelerated stability study. The dry nutrient medium was used to produce a live anthrax vaccine. Quality attributes of the vaccine were assessed for compliance with regulatory requirements. Results: The authors developed the dry media production technology. According to it, the liquid nutrient medium is fed to the drying unit at a rate of 20–25 dm3/h. The spray air pressure is 0.02 MPa. Temperatures at the drying chamber inlet and outlet are 118–122 °С and 85–90 °С, respectively. The technology was used to obtain 3 experimental batches of the dry medium. The study results demonstrate that the technology is reproducible, and the tested quality attributes of experimental medium batches are consistent with the requirements. According to the accelerated stability study, the shelf life of the dry nutrient medium at 2–30 °С is at least 3 years. Experiments demonstrated the possibility of using the dry nutrient medium for live anthrax vaccine production. Critical quality attributes of the vaccine obtained with the medium met regulatory requirements. Conclusions: The developed technology allows for the production of a standard dry nutrient medium with a prolonged shelf life, which is convenient for live anthrax vaccine production
Manufacturing of Hybridomas-Producers of Monoclonal Anti-Bodies to Tularemia Agent Antigens
Carried out have been two experimental studies on hybridization of mouse myeloma cells and lymphocytes of BALB/c mice immunized with inactivated microbe Francisella tularensis cultures. As a result obtained have been hybridomas-producers of monoclonal antibodies (MAb) specific to the antigens of tularemia agent. Evaluated have been the prospects of its application for the detection of the agent under discussion using enzyme-linked immunoassay. Established is the fact that monoclonal antibodies produced by 31G1F10, 32E5D3, 35B11C8, 36C2F11 hybridomas make it possible to identify microbe cells of various tularemia agent strains when concentrated up to 0.5·106 mc/sm3, and do not interact with cultures of heterologous microorganisms when concentrated to 1.0·108 mc/sm3, which testifies to their specificity. These MAb are planned to be used for the construction of immune-enzyme and immune-chromatographic test-systems designed for tularemia agent detection
Alien Registration- Breton, Honore (Lewiston, Androscoggin County)
https://digitalmaine.com/alien_docs/30621/thumbnail.jp
ПРОСТАТИЧЕСКАЯ ИНТРАЭПИТЕЛИАЛЬНАЯ НЕОПЛАЗИЯ: ГИСТОЛОГИЧЕСКИЕ АССОЦИАЦИИ
The authors determined the detection rates of prostatic intraepithelial neoplasia (PIN) in 2317 patients with benign prostatic hyperplasia (BPH) and prostate cancer (PC); and those of chronic prostatitis and fibrosis in patients with PIN, BPH, or PC. There was no difference in median age between the groups. PC was found to be more concurrent with PIN 2 than with BPH. The severer inflammation or fibrosis is, more likely there is a concomitance with PIN 2 or PC. There is evidence for the theory of inflammation is a factor of carcinogenesis. Prostatic fibrosis may also initiate carcinogenesis.Определена частота выявления простатической интраэпителиальной неоплазии (ПИН) у 2317 пациентов с доброкачественной гиперплазией (ДГПЖ) и раком (РПЖ) предстательной железы, хронического простатита и фиброза у больных ПИН, ДГПЖ и РПЖ. Средний возраст пациентов не имеет отличий. РПЖ чаще сочетается с ПИН 2, чем ДГПЖ. Чем выраженнее воспаление или фиброз, тем вероятнее сочетание с ПИН 2 или РПЖ. Получено подтверждение теории о воспалении как факторе канцерогенеза. Фиброз предстательной железы также может инициировать канцерогенез
ТВЕРДОСТЬ, АДГЕЗИОННАЯ ПРОЧНОСТЬ И ТРИБОЛОГИЧЕСКИЕ СВОЙСТВА АДАПТИВНЫХ НАНОСТРУКТУРНЫХ ИОННО-ПЛАЗМЕННЫХ ВАКУУМНО-ДУГОВЫХ ПОКРЫТИЙ (Ti,Al)N–Mo2N
The article reviews the properties of nanostructured multilayer coatings (Ti, Al)N–Mo2N obtained by plasma-ion vacuum arc deposition method (arc-PVD). The thickness of coating layers was comparable to the size of a grain, which was about 30–50 nm. Coating hardness reached 40 GPa with relative plastic work of deformation of about 60 %. It was found by the measuring scratching method that cohesive nature of coating destruction takes place entirely by a plastic strain mechanism, which was the evidence of its high viscosity. Local coating abrasion to a substrate level occurred at a load in the order of 75 N. Under test conditions as per «pin-on-disk» scheme using the opposing Al2O3 element at a load of 5 N, coating friction factor was equal to 0,35 and 0,50 at 20 °C and 500 °C respectively. Besides, it was practically not worn due to formation of MoO3 oxide in the friction zone (Magneli phase) which served as a solid lubricant. The increase in friction factor and appearance of significant wear were observed with further rising of test temperature. Such effect was due to intensified sublimation of MoO3 from friction surfaces with subsequent reduction of its lubricating efficiency.Исследованы свойства наноструктурных мультислойных покрытий состава (Ti,Al)N–Mo2N, полученных методом ионно-плазменного вакуумно-дугового осаждения (arc-PVD). Толщина слоев покрытия сопоставима с размером зерна, который составлял порядка 30–50 нм. Твердость покрытий достигала 40 ГПа с относительной работой пластической деформации около 60 %. Методом измерительного царапания установлено, что когезионный характер разрушения покрытия происходит исключительно по механизму пластического деформирования, что свидетельствует о высокой его вязкости. Локальное истирание покрытия до подложки происходило при нагрузке порядка 75 Н. Коэффициент трения покрытия в условиях испытаний по схеме «стержень–диск» с применением контртела из Al2O3 при нагрузке 5 Н составлял 0,35 и 0,50 при температурах 20 и 500 °C соответственно. При этом оно практически не изнашивалось из-за образования в зоне трения оксида MoO3 (фазы Магнели), работающего в качестве твердого смазывающего материала. При дальнейшем повышении температуры испытания наблюдалось повышение коэффициента трения и появление заметного износа, что связано с интенсификацией процессов сублимации MoO3 с рабочих поверхностей и снижением эффективности его работы как смазывающего материала
Evolution of three-dimensional correlations during the photoinduced melting of antiferromagnetic order in La
Using time-resolved resonant soft x-ray diffraction, we measure the evolution of the full three-dimensional scattering volume of the antiferromagnetic superlattice reflection in the single-layer manganite La<sub>0.5</sub>Sr<sub>1.5</sub>MnO<sub>4</sub> on femtosecond time scales following photoexcitation. We find that the in-plane correlations are unchanged as a metastable state is entered, however there are subtle changes in the c-axis correlations. We observe a transient shift of the scattering ellipsoid along (00L) at very short times, and at longer time scales the short-range c-axis correlations are more robust than they are in equilibrium. Such results are not obtainable with any other techniques and hint at previously unresolved processes in the dynamics of photomelting in strongly correlated systems
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