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2021 ◽  
Vol 50 (1) ◽  
pp. 8-8
Author(s):  
Editorial Board

Over the past 10 years in Russia, there has been an intensive increase in the incidence of malignant tumors of the reproductive system in women, whose share in the structure of oncological diseases amounted to 36.9%. The current situation is primarily due to an increase in the incidence of malignant tumors of the mammary gland, endometrium, and ovaries. The incidence of breast cancer is growing at a particularly fast pace. Over the past decade, the indicators have increased by more than 70%. The emerging trend towards a decrease in the incidence of cervical cancer in the 70-80s was replaced by a new rise in the period 1990-1999, mainly due to the II-III stages of the disease. The main peak of incidence corresponds to the age period of 56-65 years with a tendency to "rejuvenate" breast cancer up to 35-50 years.


Author(s):  
В.Б. Заалишвили ◽  
Д.А. Мельков ◽  
А.Ф. Габараев ◽  
Т.И. Мерзликин

Исследования нелинейных явлений в грунтах, начатые в России почти 60 лет назад, явились стимулом современного развития исследований сейсмоаномальных явлений в комплексе геофизических показателей, наблюдающихся при сильных и разрушительных землетрясениях. Кроме чисто научных интересов большой интерес вызывает вопрос прогнозирования поведения грунтов и сооружений с точки зрения адекватности ожидаемому проявлению сейсмического воздействия. Адекватное изучение нелинейности, являющейся неотъемлемой характеристикой природных явлений, позволит приблизить соответствующее антисейсмические мероприятия к реальным особенностям проявлений сейсмического эффекта при сильных землетрясениях. Цельюработы являлось построение расчетной модели, описывающей явления, наблюдаемые в грунтовой среде при сильных сейсмических воздействиях и сопоставление расчетных данных с результатами инструментальных наблюдений. Методы. В работе анализируется иснтрументальная запись, полученная на слабых грунтах, на сонове вейвлет нанализа. Моделируются импульсы различной проолжитлеьности в среде с различной стпенью проявления нелинейных свойст (кртутизны нелиненйой заивисисмоти напряжение -деформация) методом конечных элементов. Результаты. В результате установлены различия в спектральном составе моделируемых импульсов. Сильное проявление нелинейных свойств характеризуется резкими изменениями фаз колебаний, в фазах высокой скорости нарастания амплитуд. В нелинейных спектрах происходит перераспределение энергии в более высокочастотную область, кратную основному пику, тем сильнее, чем сильнее нелинейность кривой наряжение-деформация. Studies of nonlinear phenomena in soils, which began in Russia almost 60 years ago, have stimulated the modern development of studies of seismically anomalous phenomena in the complex of geophysical indicators observed during strong and destructive earthquakes. In addition to scientific interests, the issue of forecasting the behavior of soils and structures from the point of view of adequacy to the expected manifestation of seismic impact is of great interest. An adequate study of nonlinearity, which is an integral characteristic of natural phenomena, will make it possible to bring the corresponding antiseismic measures closer to the real features of the manifestations of the seismic effect during strong earthquakes. Aim. The aim of the work was to build a computational model describing the phenomena observed in a soil medium under strong seismic effects and to compare the computed data with the results of instrumental observations. Methods.The paper analyzes an instrumental record obtained on soft soils using wavelet analysis. With the help of the finite element method pulses of different duration are modeled in a medium with different degrees of nonlinear properties manifestation (steepness of nonlinear stress-strain dependence). Results. As a result, differences in the spectral composition of the modeled pulses were determined. A strong manifestation of nonlinear properties is characterized by sharp changes in the phases of vibrations, in the phases of a high rate of amplitude rise. In nonlinear spectra, the energy is redistributed to a higher frequency region, which is a multiple of the main peak and the stronger the nonlinearity of the stress-strain curve is stronger.


Biology ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 26
Author(s):  
Rita Carrotta ◽  
Maria Rosalia Mangione ◽  
Fabio Librizzi ◽  
Oscar Moran

The early impairments appearing in Alzheimer’s disease are related to neuronal membrane damage. Both aberrant Aβ species and specific membrane components play a role in promoting aggregation, deposition, and signaling dysfunction. Ganglioside GM1, present with cholesterol and sphingomyelin in lipid rafts, preferentially interacts with the Aβ peptide. GM1 at physiological conditions clusters in the membrane, the assembly also involves phospholipids, sphingomyelin, and cholesterol. The structure of large unilamellar vesicles (LUV), made of a basic POPC:POPS matrix in a proportion of 9:1, and containing different amounts of GM1 (1%, 3%, and 4% mol/mol) in the presence of 5% mol/mol sphingomyelin and 15% mol/mol cholesterol, was studied using small angle X-ray scattering (SAXS). The effect of the membrane composition on the LUVs–Aβ-peptide interaction, both for Aβ1–40 and Aβ1–42 variants, was, thus, monitored. The presence of GM1 leads to a significant shift of the main peak, towards lower scattering angles, up to 6% of the initial value with SM and 8% without, accompanied by an opposite shift of the first minimum, up to 21% and 24% of the initial value, respectively. The analysis of the SAXS spectra, using a multi-Gaussian model for the electronic density profile, indicated differences in the bilayer of the various compositions. An increase in the membrane thickness, by 16% and 12% when 2% and 3% mol/mol GM1 was present, without and with SM, respectively, was obtained. Furthermore, in these cases, in the presence of Aβ40, a very small decrease of the bilayer thickness, less than 4% and 1%, respectively, was derived, suggesting the inhibiting effect that the presence of sphingomyelin has on the GM1–Aβ interaction.


Nature ◽  
2021 ◽  
Vol 600 (7890) ◽  
pp. 621-624
Author(s):  
A. J. Castro-Tirado ◽  
N. Østgaard ◽  
E. Göǧüş ◽  
C. Sánchez-Gil ◽  
J. Pascual-Granado ◽  
...  

Agriculture ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 8
Author(s):  
Bingfei Bao ◽  
Shengtian Jin ◽  
Lilian Li ◽  
Kaifeng Duan ◽  
Xiaomei Gong

Based on the grain production data of the counties (cities, districts) in Poyang Lake Basin, this paper uses the productivity index of Epsilon Based Measure of Malmquist Luenberger (EBM-ML Index) to analyse the green total factor productivity (GTFP) of grain in Poyang Lake Basin. Kernel density function and Markov analysis are used to discuss the dynamic evolution process of the distribution of GTFP of grain. The results show the following: (1) From the time dimension, the GTFP of grain is on the rise and fluctuates more frequently from 2001 to 2017, and its trend of change is determined by the combination of technical efficiency and technological progress. Moreover, from a spatial dimension, the number of counties (cities, districts) with GTFP of grain greater than 1.0 has shown an overall increase, indicating that the overall level of GTFP of grain is increasing. (2) According to the kernel density estimation results, the crest of the main peak of the kernel density curve corresponding to the GTFP of grain in Poyang Lake Basin shifts to the right, and the area formed by the right part of the GTFP of grain corresponding to the crest of the main peak of its kernel density curve gradually increases. The peak of the kernel density curve changes from “multi-peak mode” to “single-peak mode,” and the height of the main peak of the kernel density curve of GTFP of grain shows an overall decrease. Meanwhile, the right tail of the kernel density curve shows an overall extending trend. (3) According to the estimation results of the Markov chain, the GTFP of grain in Poyang Lake Basin is highly mobile from 2001 to 2017, and the counties (cities, districts) have a certain degree of agglomeration in the low, medium-low, medium-high and high levels. In other words, the long-term equilibrium state of growth of GTFP of grain remains dispersed in the state space of four level types, indicating that the divergence state of GTFP of grain in counties (cities, districts) of Poyang Lake Basin will continue for a long time in the future. The study reveals the evolution and dynamic change of GTFP of grain in Poyang Lake Basin, which has important theoretical significance and practical value for optimizing the spatial pattern and realizing the balanced development of GTFP among counties (cities, districts) of Poyang Lake Basin and consolidating China’s food security strategy.


Author(s):  
Abolhassan Najafi ◽  
Mahdi Khoeini ◽  
Gholamreza Khalaj ◽  
Amirhossein Sahebgharan

Abstract In the present research, the use of electronic waste in the synthesis of silver nanoparticles was investigated. For this purpose, electronic scraps were used as a consumable part to synthesize silver nanoparticles. The results revealed that by optimizing the time and temperature of the dissolution process using nitric acid solution up to 90%, silver can be extracted from these parts. The temperature of 60°C and the duration of one hour were determined as the optimum conditions for this phase. Afterward, the synthesis of silver nanoparticles was checked using silver nitrate solution. The results indicated that the concentration of initial silver nitrate had a significant impact on the quality of the final product so that the best conditions for the synthesis of silver nanoparticles with suitable properties were provided at 1 molar concentration. Phase studies indicated that the main phase of the synthesized silver particles had an FCC structure and no unwanted phase was observed. Ultraviolet-visible analysis of the synthesized powder revealed that the main peak for the silver nanoparticles appeared in the wavelength range of 400 to 450 nm. DLS analysis revealed that precursor's particles inside the sol were below 15 nm. Based on AFM and TEM investigations, the particles synthesized under these conditions had nanometric spherical morphology with uniform particle size distribution.


2021 ◽  
Vol 105 (1) ◽  
pp. 77-84
Author(s):  
Patrícia Guricová ◽  
Ondřej Čech ◽  
Tomáš Kazda

Extraction of the cathode material from disassembled Samsung 18650 cell with LiCoO2 (LCO) chemistry was performed. The effect of dissolving with industrially used organic solvents is compared with the effect of selected ecological options. In successfully separated powders were studied structural changes as a function of aging and storage time. Ex-situ X-ray diffraction analysis was used for observation of differences between materials separated from cell in a fresh state and aged cell. Phase transition happening in the LiCoO2 material during cycling of the battery but also when in contact with air are discussed. Shift of the main peak (0 0 3) and (1 0 4) for the aged cathode material are displayed and discussed.


MAUSAM ◽  
2021 ◽  
Vol 61 (4) ◽  
pp. 569-576
Author(s):  
A. KASHYAPI ◽  
A. L. KOPPAR ◽  
A. P. HAGE

The spatial and temporal distributions of heat unit and various agrometeorological indices for the rice crop, are studied in this paper. Eight ET – stations were selected from six rice growing zones, viz., Canning (in lower Gangetic plains), Bikramganj and Varanasi (in middle Gangetic plains), Ludhiana (in trans Gangetic plains), Ranchi, Shymakhunta (in eastern plateau and hills), Annamalai Nagar (in east coast plains and hill region) and Pattambi (in western plains and ghat region). Eleven crop growth stages were identified for this  study, viz., germination, nursery seedling, transplanting, tillering, active tillering, lag phase, panicle initiation, flowering, grain formation, grain maturity and harvesting, the duration of each of the growth stages varied widely, station wise. Daily data were collected growth stagewise for latest available five years and the mean values were computed for the derived parameters, viz., the crop requirements of heat unit, agroclimatic rainfall index (ARI), yield moisture index (YMI), aridity index (AI). The study revealed that for rice crop the total degree days requirement varied from 1706 degree – days (at Ranchi) to 2815 degree – days (at Shymakhunta). It showed primary peak (with 16.7 % of total requirement) at active tillering stage. The ARI values were mostly higher than 100 per cent. The mean YMI values varied widely from 477 mm (at Bikramganj) to 1523 mm (at Pattambi). The values showed main peak at active tillering stage. The AI values showed moderate aridity at early growth stages, which increased at advanced crop growth stages.


2021 ◽  
Vol 9 (12) ◽  
pp. 2419
Author(s):  
Paulina Pradel ◽  
Nancy Calisto ◽  
Laura Navarro ◽  
Andrés Barriga ◽  
Nicolás Vera ◽  
...  

Carotenoids are highly important in pigmentation, and its content in farmed crustaceans and fish correlates to their market value. These pigments also have a nutritional role in aquaculture where they are routinely added as a marine animal food supplement to ensure fish development and health. However, there is little information about carotenoids obtained from Antarctic bacteria and its use for pigmentation improvement and flesh quality in aquaculture. This study identified carotenoids produced by Antarctic soil bacteria. The pigmented strain (CN7) was isolated on modified Luria–Bertani (LB) media and incubated at 4 °C. This Gram-negative bacillus was identified by 16S rRNA analysis as Flavobacterium segetis. Pigment extract characterization was performed through high-performance liquid chromatography (HPLC) and identification with liquid chromatography–mass spectrometry (LC–MS). HPLC analyses revealed that this bacterium produces several pigments in the carotenoid absorption range (six peaks). LC–MS confirms the presence of one main peak corresponding to lutein or zeaxanthin (an isomer of lutein) and several other carotenoid pigments and intermediaries in a lower quantity. Therefore, we propose CN7 strain as an alternative model to produce beneficial carotenoid pigments with potential nutritional applications in aquaculture.


Author(s):  
. Vaishali ◽  
Sudhanshu Ranjan Swain ◽  
Santosh Kumar Verma

The purpose of this exploration research work article is to develop equivalent method and evaluate its equivalency (Cross validation) against pharmacopoeial method of Montelukast sodium for the evaluation and assessment of process related impurities i.e. Methyl MLK impurity in Montelukast sodium by HPLC method and its principles. The method mentioned in European Pharmacopoeia (EP) and United States Pharmacopoeia (USP) does not sufficiently separates impurity C and impurity D , as these impurities elutes under the main peak and the pharmacopoeial methods were also not able to detect the Methyl MLK impurity which is not listed in USP monograph. So our prime design of experiment is to develop of new high-performance liquid chromatographic (HPLC) method which eliminates the drawback of two pharmacopoeial methods and this proposed created strategy is fit for recognition and detection of Methyl MLK impurity and separation of all process related impurities of Montelukast sodium mentioned in EP and USP monographs. An efficient strategy screening and scouting in which various C-18 columns were tried and tested. LUNA C-18 column utilized in RP HPLC mode ended up being the phenomenal decision for the technique streamlining. The proportion of acetonitrile and trifluoroacetic acid (TFA) in water and in the mobile phase, column temperature, flow rate and diluents were considered as basic strategy boundary. The method developed equivalency was checked in terms of Specificity, LOD, Quantitation (LOQ), Precision, Linearity, Relative response factor (RRF), and Accuracy.


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