Investigation of the EXAFS Cumulants of Silicon and Germanium Semiconductors by Statistical Moment Method: Pressure Dependence

Pressure dependence of Extended X-ray Absorption Fine Structure (EXAFS) cumulants of silicon and germanium have been investigated using the statistical moment method (SMM). Analytical expressions of the first and second cumulants of silicon and germanium have been derived. The equations of states for silicon and germanium semiconductors have been also obtained using which the pressure dependence of lattice constants and volume of these semiconductors have been estimated. Numerical results using the developed theories for these semiconductors are found to be in good and reasonable agreement with those of the other theories and with experiment

Pressure Dependence of EXAFS Debye-Waller Factors in Crystals

In present article the pressure dependence of Debye-Waller factors in crystals has been investigated by using statistical moment method and anharmonic correlated Einstein model. These two methods provide similar results which indicate that the Debye-Waller factors of crystals decreases slightly under high pressure. Our numerical results for several crystals are compared to other theoretical and experimental values and showed a good agreement

Influence of Temperature And Concentration of Ethanol on Properties of Borosilicate Glass Photonic Crystal Fiber Infiltrated by Water – Ethanol Mixture

In this paper, we present a numerical simulation of the properties of a photonic crystal fiber (PCF) made of borosilicate glass infiltrated by the water-ethanol mixture. We examine the influence of temperature and ethanol concentration for the refractive index, dispersion properties, effective mode area and confinement loss of the fundamental mode by a Lumerical simulation method. We also calculate the fundamental mode of the fiber infiltrated with a water-ethanol mixture with the concentration range of ethanol from 0% to 100% in the temperature range from 10°C to boiling point of ethanol. The results show that all fibers infiltrated with water-ethanol mixture have flat dispersion characteristics in the infrared range above 1.32. The best flatness exists for pure ethanol. Furthermore, it is possible to shift the zero-dispersion wavelength and modify fundamental properties of PCFs by both temperature and concentration of ethanol. The results obtained are important because of that we not only use their reasonable parameters for the design and manufacture but also use them in nonlinear phenomena and nonlinear applications of fibers as supercontinuum generation

PRELIMINARY STUDY OF THE ANTIOXIDANT PROPERTIES OF OPHIOCORDYCEPS SOBOLIFERA

The aim of study was to determine preliminary phytochemical analysis and the antioxidant potential of Ophiocordyceps sobolifera. The antioxidant activity of Ophiocordyceps sobolifera was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and total antioxidant activity methods. Phytochemical analyses revealed the presence of steroids, triterpenoids, alkaloids, phenolics, flavoinods, protein, carbohydarte and saponins. The antioxidant activity of the ethanol extracts and water extracts showed high antioxidant activity with the lowest half maximal inhibitory concentration (IC50) values to 0.70 from 0.95mg/mL, realtively. Total antioxidant capacity of the O. sobolifera showed contained from 5.52 ± 0.14 to 12,71 ± 0.23 mg GA/g or from 3.55 ± 0.15 to 7.87 ± .05 μmol AS/g. These data suggest that O. sobolifera is a natural source of antioxidants

Numerical simulation of all-normal dispersion visible to near-infrared supercontinuum generation in photonic crystal fibers with core filled chloroform

This study proposes a photonic crystal fiber made of fused silica glass, with the core infiltrated with chloroform as a new source of supercontinuum (SC) spectrum. We numerically study the guiding properties of the fiber structure in terms of characteristic dispersion and mode area of the fundamental mode. Based on the results, we optimized the structural geometries of the CHCl3-core photonic crystal fiber to support the broadband SC generations. The fiber structure with a lattice constant of 1 μm, a filling factor of 0.8, and the diameter of the first-ring air holes equaling 0.5 μm operates in all-normal dispersion. The SC with a broadened spectral bandwidth of 0.64 to 1.80 μm is formed by using a pump pulse with a wavelength of 850 nm, 120 fs duration, and power of 0.833 kW. That fiber would be a good candidate for all-fiber SC sources as cost-effective alternative to glass core fibers

In vitro antioxidant activity and content of bioactive compounds from Homalomena occulta

Homalomena occulta, a plant widely used in traditional Vietnamese medicine, was assessed for its antioxidant potential through DPPH radical scavenging and total antioxidant capacity methods. The results showed that Homalomena occulta exhibited significant antioxidant activities with a low IC50 value of 40.27 μg/mL, which is comparable to that of curcumin (38.50 μg/mL). Furthermore, the total antioxidant capacity of the Homalomena occulta extract was determined to be 77.48 ± 2.34 mg GA/g. To investigate the composition of the plant, various compounds including total phenolic, total flavonoid, polysaccharides, and triterpenoids were quantified using colorimetric methods with specific reagents. The content of phenolic compounds, flavonoid compounds, polysaccharides, and triterpenoids in Homalomena occulta was found to be 36.87 ± 0.42 GAE/g, 26.83 ± 0.29 mg QUE/g, 5.06 ± 0.06%, and 52.09 ± 1.77 mg Olenanoic/g, respectively. Notably, this study provides the first-ever report on the polysaccharide and total triterpenoid content of Homalomena occulta

In vitro antioxidant activity and bioactive compounds from Calocybe indica

Nowadays, the use of mushrooms in medicine is ubiquitous and has achieved particular success. The antioxidants in mushrooms can deactivate free radicals. This study assesses the antioxidant potential of mushroom Calocybe indica with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging methods and the total antioxidant capacity. The mushroom’s ethanol extract exhibits acceptable activity with a low IC50 value (240.11 μg/mL), approximately 2.9 times lower than that of the mushroom Ophiocordyceps sobolifera extract. The ABTS scavenging rate of the extract is around 60% at 500 µg/mL, and the total antioxidant capacity is equivalent to 64.94 ± 1.03 mg of GA/g or 77.42 ± 0.42 μmol of AS/g.  The total phenolics, flavonoids, polysaccharides, and triterpenoids are equivalent to 29.33 ± 0.16 mg of GAE/g, 17.84 ± 0.11 mg of QUE/g (5.04 ± 0.04%), and 4.96 ± 0.04 mg of oleanolic acid/g, respectively. Specifically, the total triterpenoid content has been reported for the first time. The mushroom can have potential biomedical applications

Polysaccharide extraction from Myxopyrum smilacifolium trunk and its antioxidant capacity

As a traditional medicinal plant in Vietnam, Myxopyrum smilacifolium has been used for a long history to treat cough, nervous disorders, numbness, rheumatism, and cephalalgia. Nevertheless, reports on the antioxidant activity and extraction of M. smilacifolium polysaccharides are still very rare. This study was designed to extract a high yield of polysaccharides from the M. smilacifolium trunk and characterize it. As a result, the maximum yield of the polysaccharides of 5.13 ± 0.05% was obtained with an extraction time of three hours, extraction temperature of 100 oC, the ratio of water to sample of 1:50 as extraction solution, extraction number of times 3, and the ratio of ethanol to extract volume 5:1 (v/v). Polysaccharides was characterized by Fourier transform infrared spectroscopy (FT-IR) and high-performance gel-permeation chromatography (HPGPC). The average molecular weight of extracted polysaccharides was around 3.78 × 105 Da. In vitro assays dan impressive antioxidant activities of the extracted polysaccharides, containing 0.2423 ± 0.0028 mg GA/g or 0.2142 ± 0.0007 μmol AS/g. The IC50 values of polysaccharides in the DPPH and ABTS methods were 0.89 mg/mL and 3.85 mg/mL, respectively.  These findings exhibited the potential for application or further research and development of polysaccharides from Myxopyrum smilacifolium

Состояние провоспалительного цитокинового звена у больных с нестабильной стенокарадией и сахарным диабетом 2-го типа в зависимости от функционального класса хронической сердечной недостаточности

Проанализировано состояние провоспалительного звена цитокинов у больных с нестабильной стенокардией (НС) и сопутствующим сахарным диабетом (СД) 2−го типа в зависимости от функционального класса хронической сердечной недостаточности (ХСН). Нарастание проявлений сердечной декомпенсации у больных с НС и СД 2−го типа ассоциируется с высокой активностью провоспалительного цитокинового звена, представленного фактором некроза опухолей−α и интерлейкином−6. Повышение функционального класса ХСН характеризуется увеличением инсулинорезистентности у больных с НС и СД 2−го типа.Проаналізовано стан прозапальної ланки цитокінів у хворих із нестабільною стенокардією (НС) та супутнім цукровим діабетом (ЦД) 2−го типу залежно від функціонального класу хронічної серцевої недостатності (ХСН). Наростання проявів серцевої декомпенсації у хворих із НС та СД 2−го типу асоціюється з високою активністю прозапальної цитокінової ланки, представленої фактором некрозу пухлин−α та інтерлейкіном−6. Підвищення функціонального класу ХСН характеризується зростанням інсулінорезистентності у хворих із НС та ЦД 2−го типу.The state of pro−inflammatory cytokines in patients with unstable angina (UA) and associated type 2 diabetes mellitus (DM) was analyzed depending on the functional class of chronic heart failure (CHF). The increase in manifestations of cardiac decompensation in patients with UA and type 2 DM is associated with high activity of pro−inflammatory cytokine level represented by tumor necrosis factor−β and interleukin−6. Increase of functional class of CHF is characterized by increased insulin resistance in patients with UA and type 2 DM