Influence of X-ray on the autophagic-lysosomal system in rat pancreatic acini

Lysosomes have an important role in radiation injury of cells and tissues. Activation of autophagy is frequently observed in different types of pathological tissue degeneration. In radiation response it increases in some cases, and lysosomes are responsible for regulated degradation of the autophagic vacuoles. Lysosomes are also involved in ionizing radiation induced cell death. In apoptosis lysosomes degrade content of the phagocytotic vacuoles derived from engulfed apoptotic blebs. On the other hand lysosomal enzymes discharged from disintegrated cells have a key role in induction of necrotic changes. In this work we investigate autophagy and lysosomal protein degradation in the relatively radiation insensitive exocrine pancreatic acini in vivo and in vitro. Type of cell death induced by X-ray was also examined in relation to the changes of the lysosomal processes. In 5h after 16 Gy in vivo whole body irradiation we observed significant increase in the cytoplasmic volume fraction of autophagic vacuoles and in the number of apoptotic cells in vivo. But in the acini isolated from irradiated rats we could not detect a change in the lysosomal degradation of intracellular proteins. Therefore irradiation probably influences the autophagy in an earlier step than lysosomal degradation. Extended necrotic lesions were not observed in vivo as long as 48 h. Isolated pancreatic acini usually contain more autophagic vacuoles than in vivo, but we could not observe additional increase in autophagy after 8 Gy, in vitro irradiation. Lysosomal degradation of intracellular proteins was also unaltered after 8 Gy, in vitro irradiation. Other biochemical functional parameters of the isolated pancreatic acini, like protein synthesis and amylase secretion were not changed either after 8 Gy, in vitro X-ray treatment. These results indicate that pancreatic acinar cells in vitro have a high tolerance to irradiation. The observed in vivo radiation induced changes of the exocrine pancreas are possibly indirectly induced by injuries of more sensitive mechanisms.     

石墨狭缝中甲烷吸附的分子动力学模拟

用分子动力学模拟研究石墨狭缝中甲烷的吸附,考察狭缝宽度和温度对甲烷吸附的影响.模拟发现甲烷在石墨狭缝中出现分层现象,吸附层中甲烷具有类液特征,第一吸附层内甲烷中总有两个氢原子的连线与另外两个氢原子的连线分别位于平行于狭缝壁的两个平面内,游离层中甲烷呈现气体的特征;碳原子间的平均作用势说明吸附层中甲烷分子间结合能力大于游离层,吸附态是甲烷在石墨狭缝中的主要赋存形式之一;伦敦力以及由吸附层净电荷产生的电场力是甲烷吸附和分层的主要原因;甲烷的吸附量随狭缝宽度增大或温度升高而减少,当狭缝宽度小于16.46Å时,甲烷仅以吸附形态存在.甲烷在第一吸附层中的扩散能力最弱、游离层中最强,甲烷扩散系数随狭缝宽度的增大或温度的升高而增大.     

Spectral Properties of Single BODIPY Dyes in Polystyrene Microspheres and in Solutions

The absorption, fluorescence, fluorescence quantum yield, and photostability of five BODIPY dyes are characterized and compared as single dyes in two environments, in 40-nm polystyrene spheres and in solution. The absorption and fluorescence spectra of the dyes in spheres are similar in profile but shifted to lower energies compared to those in solution. All the dyes are highly fluorescent, with three having fluorescence quantum yields of 1.0. For three of the five dyes, the yields were the same in spheres as in solution (1.00, 1.00, and 0.73). The high concentration of these dyes in spheres does not quench their fluorescence. For two other dyes the yields dropped, from 1.00 to 0.55 in one case and 0.83 to 0.50 in another, comparing the dyes in solution versus in spheres. The photodegradation of the dyes decreases in spheres compared to in solution in all but one case. For one dye, it decreases as much as 800-fold. Dyes overlooked because of low fluorescence or stability in solution could become useful fluorescent materials in the microsphere environment.     

Effect of ausforming temperature and strain on the bainitic transformation kinetics of a low carbon boron steel

The effect of ausforming temperature and strain on the bainitic transformation kinetics was investigated in a low carbon boron steel. A new mechanism, which is based on the competition between the increase in nucleation rate and the decrease in average volume of bainite sheaf after deformation, is proposed. The increase in nucleation rate is due to the decrease in boron concentration at the grain boundaries after small deformation and the formation of sub-grain boundaries at the grain interior after large deformation. The decrease in average volume of bainite sheaf is ascribed to the frequent impingement of bainite sub-units after deformation. The increase in nucleation rate after deformation results in the decrease in incubation time, which is confirmed from the experiment. The increase in nucleation rate overcomes the decrease in average volume of bainite sheaf, resulting in the increase in transformation velocity and volume fraction after small deformation. On the contrary, the decrease in the average volume of bainite sheaf overcomes the increase in nucleation rate after large deformation, leading to the decrease in transformation velocity and volume fraction of bainite.     

Technological applications of Mössbauer spectroscopy

A brief review is given of some recent industrial applications of Mossbauer spectroscopy. One of the most desirable futures of the Mossbauer effect is the feasibility of performing in situ measurements. Such measurements are extremely important especially in the upgrading of coal derived liquids. Such applications have been very successful in understanding the role of iron sulfides stoichiometries in direct coal liquefaction. The use of in situ techniques in invaluable in the investigation of the metal support interaction and their relation to carburization processes in Fischer-Tropsch reactions. Some examples of such applications will be presented in this paper. In this paper, emphasis will be placed in the use of a multiple technique approach to elucidate scientific problems of industrial importance.     

Certain general questions of fast-electron transport II. Kinetic equations and conditions governing the accelerated motion of fast electrons in dielectrics in an electric field

A general kinetic equation for the differential density of fast particles moving in a medium in an external field is derived on the basis of the continuity equation in phase space. An equation is written for the differential flux in the case of fixed target particles. This equation is used to derive equations for fast electrons; account is taken of the coupling of energy-loss and scattering events in an electric field for various particular problems analogous to those studied in the theory of electron transport in the absence of a field. The kinetic equations are used to analyze the conditions governing accelerated motion of electrons in a dielectric in an external electric field in the continuous-deceleration approximation. Account is taken of fluctuations in the energy loss and of multiple scattering. There are two energy ranges of particles moving in a dielectric in which accelerated motion can occur; in the case of an electron beam with a continuous energy spectrum, this acceleration would be accompanied by monochromatization of the beam.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 7–12, February, 1972.     

ICP-AES测定云南楚雄糖尿病患者发样微量元素的研究

探讨微量元素与糖尿病间的关联性及临床意义。采用ICP-AES等离子体发射光谱仪测定了楚雄地区糖尿病患者人发中11种元素,采用2,3-二氨基萘荧光法测定发样中的硒元素。选取糖尿病患者120例,对照组35例。糖尿病组发样中常量元素Ca、Mg低于对照组,P高于对照组;除Cd、Cr、Fe外,微量元素Zn、Se、Ni、Mn、Cu等5种元素低于对照组,并有显著差异(P0.01)。糖尿病组间性别比较数据显示男性除发Ni、Mn、P外,其余元素含量均低于女性,其中发锌远低于女性。3个不同年龄段糖尿病人群的微量元素含量变化显示Fe、P2种元素随年龄增加含量增高;Mg、Cd2种元素随年龄增加含量减少;其余各元素变化情况为Fe、P元素在老年组中较高,Cu、Cd、Mg较低;Mn、Cr、Cu元素含量在中年组中较高,而Zn、Se略低;Zn、Se在青年组较高,而Mn、Cr低。城市人群发中Zn、Cd、Cu、Mg、Ca含量比农村人群高;Se元素含量二者间差别也不大,其余元素含量均低于农村人群。楚雄地区糖尿病患者发中Zn、Se、Mg、Mn4种元素水平低,楚雄地区糖尿病患者致病原因可能与地区属低Se水平和患者体内硒水平低有关。     

利用原子吸收光谱法分析盐胁迫对野生披碱草矿质元素吸收和积累的影响

应用原子吸收光谱法测定了两份耐盐性不同的野生披碱草种质材料在不同盐浓度胁迫条件下根组织和叶组织中的大量元素(Na,K,Ca,Mg)和微量元素(Cu,Fe,Mn,Zn)含量,并对野生披碱草种质材料矿质元素吸收和积累的选择性与耐盐性的关系进行了分析,结果表明：随着盐胁迫浓度的升高,野生披碱草种质材料叶和根组织中Na含量不断增加,耐盐材料HS叶组织中的Na含量显著低于敏盐材料LS(P<0.05);而K和Ca含量呈下降的趋势,在高浓度盐胁迫下,耐盐材料HS中两种元素的含量显著高于敏盐材料LS(P<0.05);微量元素Fe和Zn在野生披碱草材料根、叶组织中的含量升高,Cu在根组织中的含量没有变化,但是在叶组织中升高,而Mn在根、叶组织中的含量都呈下降的趋势,耐盐材料HS叶组织和根组织中Zn和Fe含量低于敏盐材料LS,Mn含量显著高于敏盐材料LS(P<0.05)。     

近50年中国降水及温度变化在干旱形成中的影响

根据中国气象局1958—2007年194站的温度、降水和Palmer旱涝指数（Palmer Drought Severity Index, PDSI）均一化数据库,构建统计模型量化了温度和降水变化在干旱形成中所占的比重,尤其讨论了中国8个气候区域温度和降水变化在干旱成因中的特征.受全球增温趋势的影响,未来中国北方地区的干旱化趋势仍将继续.未来五年内干旱发生概率较大的地区主要分布在中国华北,且有持续向南扩张的趋势,一直延伸到江淮地区.在全球变暖的背景下,降水减少仍然是中国东部干旱形成的主要因素.相对于南方地 关键词： 降水 全球变暖 干旱     

Excited State Proton Transfer Reaction of 4-Methyl-2,6-dicarbomethoxyphenol in Some Protic Solvents at Room Temperature and 77K: Interaction with Base

The ground and excited state proton transfer reactions of 4-methyl-2,6-dicarbomethoxyphenol (CMOH) have been studied in water and some alcoholic solvents both in the presence and in the absence of base by means of absorption, emission, and nanosecond spectroscopy at room temperature and 77 K. Solute–solvent interaction appears to play a major role in determining the nature of absorbing and fluorescing species in these solvent media. The emission properties of CMOH have been examined in relation to those of 4-methyl-2,6-diformylphenol (MFOH). The spectral characteristics obtained indicates that CMOH in methanol, ethanol, and water exists in more than one structural form in both the ground and excited states. At 77 K the emission spectra show phosphorescence only in the presence of a base. The fluorescence decay rates of CMOH are relatively slower than those of MFOH and nonradiative decays are dominant in the decay process of CMOH. It is proposed that intramolecular hydrogen bond in CMOH is stronger compared to that in MFOH. From our theoretical calculation at AM1 level of approximation suggested that the process is thermodynamically endothermic in the ground state and also encounter high barriers. However, the process becomes exothermic in the excited state.     

Relaxation enhancement using liposomes carrying paramagnetic species

Studies were performed to investigate the effects upon the relaxation times of mouse organs of intravenously administered Mn-DTPA entrapped in multilamellar liposomes, Mn-DTPA, 0.9% NaCl entrapped in liposomes, 0.9% NaCl. Manganese concentrations in injectates and tissues were assessed with 54Mn and atomic absorption. T1 and T2 of freshly excised tissues were measured in an NMR spectrometer at 20 MHz and 37% C with IR and CPMG sequences. Entrapment of Mn-DTPA in liposomes increased 54Mn accumulation in liver by 207% and in spleen 1208% and reduced 54Mn in heart by 20% and in kidney by 24% relative to free Mn-DTPA. Statistically significant increases in relaxation rates were produced. However, the increase in relaxation rate per unit concentration of Mn in tissue is reduced by 31% in liver and 62% in spleen when Mn is delivered inside liposomes. These observations have implications for the design of NMR contrast agents.     

On the Energy of a “Two-Dimensional” Two-Electron Atom

With the use of the known solution of the Schrödinger equation for an electron in the nucleus field in the polar coordinates, the energy of a “two-dimensional” two-electron atom in the ground state, as well as its single ionization energy, has been calculated both in perturbation theory and with an almost century-old method of variation of the parameter Z in a trial wavefunction of the ground state. Since such two-dimensional atoms, e.g., helium atoms, can in principle be implemented in experiments by “freezing” of one degree of freedom in the phase of Bose–Einstein condensate, the conclusions made in this work can be tested. Fundamental features of the calculation of the energy of “one-dimensional” two-electron atoms and the formation of their Bose–Einstein condensate have also been discussed. The results obtained in this work coincide in a number of particular cases with the results obtained in a previous work, where some results were absent.     

动力学阿尔文波及其在太阳和空间等离子体中的应用

动力学阿尔文波是短波长的色散阿尔文波,其色散主要是由于垂直波长接近离子回旋半径或电子惯性长度等微观粒子动力学特征尺度而引起的。在频率远低于离子回旋频率的低频条件下,其平行波长通常仍然远大于离子惯性长度,这导致动力学阿尔文波在电磁偏振和传播方向上呈现显著各向异性的重要特性,并因此使其在磁等离子体的粒子能化现象和结构丝化现象中起重要作用。动力学阿尔文波早期于1970年代由Chen和Hasegawa研究聚变等离子体加热问题时首先提出。随后,在1980年代受到空间等离子体、特别是电离层-磁层耦合与极光现象研究的广泛关注。进入1990年代后,由于在空间卫星探测技术和地面等离子体实验技术的不断发展,特别是一些高分辨空间等离子体探测仪器和地面大型等离子体实验设备投入工作以来,在动力学阿尔文波的实验研究上取得了一系列突破性的重要进展。这不仅导致对动力学阿尔文波在磁等离子体动力学现象中重要作用的重新估价和正视,并再次激发了对动力学阿尔文波理论及其在实验室、空间和天体环境下各类等离子体活动现象中应用研究的广泛兴趣。自1990年代中期以来,我们在中国科学院紫金山天文台的研究小组一直致力于动力学阿尔文波及其在太阳和空间等离子体粒子能化现象中应用的研究。这篇综述性报告主要介绍了有关动力学阿尔文波非线性孤波理论及其在空间和太阳等离子体粒子能化现象中应用的研究进展,也是我们这十几年来在这一领域研究工作的一个总结。报告的第一章简要介绍动力学阿尔文波的一些主要特征及其在磁等离子体动力学现象中的重要作用。然后,在第二章中利用等离子体的双流体方程、结合有关的实验观测,系统介绍了动力学阿尔文波的色散、传播、偏振等基本特性和在一维孤波与二维涡旋等非线性结构理论方面的研究进展。接下来的第三、四、五章将聚焦在动力学阿尔文波的耗散机制及其在太阳和空间等离子体粒子能化现象中的应用研究上,分别包括：动力学阿尔文孤波的耗散结构及其在极光高能电子加速现象中的应用（第三章）;动力学阿尔文孤波中重离子的各向异性能化机制及其在延伸日冕中少量重离子反常加热现象中的应用（第四章）;以及动力学阿尔文波的反常耗散机制及其在日冕磁等离子体结构非均匀加热现象中的应用（第五章）。最后的第六章是一个简要的总结和几点进一步发展的展望。     

Features of interannual variations of ozone in the middle stratosphere over Moscow according to observations at millimeter waves

The features of interannual variations of ozone in the middle stratosphere over Moscow in cold half-years since 1995 to 2015 are considered. These features are most pronounced in two separated groups of winters (six winters in each group) in December–January. It appeared that the seasonal variation of ozone averaged within each group is characterized by a higher ozone concentration \({C_{{O_3}}}\) in group I (in comparison with group II) in December and lower values in January. The differences in the seasonal variation of ozone between these groups at the level of 10 mbar in December and January exceed 2 ppm. A feature of the stratosphere circulation for half-year group I is the existence of a stable polar vortex and the absence of strong midwinter perturbations and sudden stratospheric warmings. On the contrary, for cold half-years of group II, the appearance of strong stratospheric warmings in January–February is in common. The results presented provide a quantitative estimate of the effect of these stratospheric warmings on ozone of the middle stratosphere overMoscow.     

Superconductivity and superfluidity as universal emergent phenomena

Superconductivity (SC) or superfluidity (SF) is observed across a remarkably broad range of fermionic systems: in BCS, cuprate, iron-based, organic, and heavy-fermion superconductors, and in superfluid helium-3 in condensed matter; in a variety of SC/SF phenomena in low-energy nuclear physics; in ultracold, trapped atomic gases; and in various exotic possibilities in neutron stars. The range of physical conditions and differences in microscopic physics defy all attempts to unify this behavior in any conventional picture. Here we propose a unification through the shared symmetry properties of the emergent condensed states, with microscopic differences absorbed into parameters. This, in turn, forces a rethinking of specific occurrences of SC/SF such as high-T_c SC in cuprates, which becomes far less mysterious when seen as part of a continuum of behavior shared by a variety of other systems.     

Stability of bilayer lipid membrane in the presence of Co-containing metalloporphyrins

Stability of bilayer lipid membrane (BLM) in an electric field in the presence of Co-porphyrin in the solution surrounding BLM is investigated. We have shown that the presence of porphyrin in a solution reduces line tension of the pore edge and surface tension of BLM and increases the number of pores on the BLM. It is also shown that a decrease in the stability of BLM in the electric field in the presence of the porphyrin is a result of the reduction of line tension of the pore edge and increase in the number of pores.     

Japanese cedar pollinosis: Discovery,nomenclature, and epidemiological trends

The history of pollinosis in Japan before the discovery of Japanese cedar pollinosis was presented in part I in this paper. Until early 1960s, it was believed that there was no pollinosis in Japan except one case of ragweed pollinosis.The summary of how the Japanese cedar pollinosis was discovered and named was presented in part II, by referring to the paper in which we reported the presence of Japanese cedar pollinosis for the first time.The epidemiology after the discovery of Japanese cedar pollinosis was presented in part III. The number of the patients suffering from Japanese cedar pollinosis gradually increased since the 1970s. The annual incidence rate of the pollinosis had correlations with the dispersed pollen count per year. The prevalence rate of the patients with Japanese cedar pollinosis increased from 16.2% in 1998 to 26.5% in 2008 by the nationwide survey. The prevalence rate of the patients with Japanese cedar pollinosis in Tokyo metropolitan area was 10% from 1983 to 1987, 19.4% in 1996, and 28.2% in 2006.The prospects of current research and future studies were discussed in parts IV and V.     

Photostability of a C<Subscript>60</Subscript> fullerene coating as a solid-phase photosensitizer of singlet oxygen

The stability of the optical properties and the generation efficiency of singlet oxygen of a solidphase photosensitizer based on fullerene in an aqueous suspension subjected to prolonged intense irradiation with visible light are studied in comparison with a photosensitizer based on methylene blue in an aqueous solution. Changes in the absorption spectra show that, as a result of 20-min irradiation, the content of fullerene decreases by 2% from its initial value, while that of methylene blue decreases by 19%. In both cases, the dynamics of the decrease in the photosensitizing ability of the photosensitizers in the course of their irradiation correlates with the changes in their spectra, but the magnitude of this decrease in the case of the solid-phase photosensitizer is greater than the magnitude of its spectral changes because of the surface nature of the photosensitization process. The study of the absorption spectra of fullerene coatings shows that their irradiation in water or in air causes the same photodegradation of fullerene. At the same time, studies with the help of the electron spin resonance (ESR) technique reveal differences in the nature of processes undergone by fullerene in water and in air.     

Influence of the Concentration of Aqueous Solutions of Sulfuric Acid on the Reflection Spectra of Pine Needles

The effect of solutions of sulfuric acid of different concentrations on the optical characteristics of pine needles was investigated. It is found that an increase in the acid concentration results in a decrease in the content of pigments in pine needles and in their reflectance in the visible region. An analysis of experimental data by using the LIBERTY model has shown that the decrease in the pine needle reflectance with decrease in the pigment content depends on the change in the refractive index at the cell wall–binding medium interface.     

Weak localization in monolayer and bilayer graphene

We describe the weak localization correction to conductivity in ultra-thin graphene films, taking into account disorder scattering and the influence of trigonal warping of the Fermi surface. A possible manifestation of the chiral nature of electrons in the localization properties is hampered by trigonal warping, resulting in a suppression of the weak anti-localization effect in monolayer graphene and of weak localization in bilayer graphene. Intervalley scattering due to atomically sharp scatterers in a realistic graphene sheet or by edges in a narrow wire tends to restore weak localization resulting in negative magnetoresistance in both materials.