Evaluation of different culture conditions for high-level soluble expression of human cyclin A(2) with pET vector in BL21 (DE3) and spectroscopic characterization of its inclusion body structure

In this paper, we evaluated various parameters of culture condition affecting high-level soluble expression of human cyclin A, in Escherichia coli BL21(DE3), and demonstrated that the highest protein yield was obtained using TB(no glycerol) + 0.5% glucose medium at 25 degrees C. By single immobilized metal ion affinity chromatography, we got highly purified human cyclin A(2) with a yield ranged from 20 to 30 mg/L. By amyloid-diagnostic dye ThT binding and Fourier transform infrared spectroscopy, we observed a significant decrease in alpha-helix content and an increase in beta-sheet structure in cyclin A(2) inclusion body in comparison to its native protein, and confirmed the resemblance of the internal organization of cyclin A(2) inclusion body and amyloid fibrils.

Conjugate Model for Heat and Mass Transfer of Porous Wall in the High Temperature Gas Flow

Heat and mass transfer of a porous permeable wall in a high temperature gas dynamical flow is considered. Numerical simulation is conducted on the ground of the conjugate mathematical model which includes filtration and heat transfer equations in a porous body and boundary layer equations on its surface. Such an approach enables one to take into account complex interaction between heat and mass transfer in the gasdynamical flow and in the structure subjected to this flow. The main attention is given to the impact of the intraporous heat transfer intensity on the transpiration cooling efficiency.

Short-surface waves radiated by a partially-immersed 3-dimensional oscillating body

The short-surface waves generated by a 3-D arbitrarily oscillating body floating onwater are discussed. In the far-field off the body, the phase and the amplitude functions ofthe radiated waves are determined by the ray method. An undetermined constant is includ-ed in the amplitude function. From the result of Ref. [1], the near-field boundary layersolution near the body waterline is obtained. The amplitude of this solution depends on thewhole wall shape of the body and the slope at the body waterline on the cross-sections per-pendicular to the waterline. By matching the far-field solution with the near-field bound-ary layer solution, the undetermined constant in the amplitude function of the far-fieldradiated waves is determined. For the special case of a half-submerged sphere which per-forms vertical oscillating motion, the result obtained in this paper is in agreement withthat of Ref. [ 2 ].

The toxic effects of microcystin-LR on embryo-larval and juvenile development of loach, Misguruns mizolepis Gunthe

Microcystin-LR, a specific and potent hepatotoxin, was tested for its effects oil loach embryo-larval and juvenile development, The results of this study showed that loach embryos were more sensitive when exposed to microcystin-LR at a later than at an earlier stage of development, Juveniles were far less sensitive to MC-LR than were embryos and larvae. Mortality and developmental abnormality were proven to be dose-dependent and to be stage-specific sensitive. Among the abnormal changes noted were: pericardial edema and tubular heart, bradycardia, homeostasis, poor yolk resumption. small head, curved body and tail, and abnormal hatching, Liver and heart were the main targets of microcystin-LR toxicity. Ultrastructural analysis documented a complex set of sublethal effects of microcystin-LR on loach hepatocytes, chiefly including morphological alteration in nuclear and RER of loach liver cells. fit addition, microcystin-LR was lethal to loach juvenile in the subacute (7 days) exposure (LC50) = 593.3 mug/l). (C) 2002 Elsevier Science Ltd. All rights reserved.

Theoretical Analysis and New Formulae for Half-Lives of Proton Emission

The proton radioactivity half-lives of spherical proton emitters are calculated by the cluster model with the contribution of a centrifugal potential barrier considered separately. The results are compared with the experimental data and other theoretical data, and good agreement is found for most nuclei. In addition, two formulae are proposed for the proton decay half-life of spherical proton emitters through the least squares fit to the experimental data available, and could reproduce the experimental half-lives successfully.

Cluster preformation in heavy nuclei and radioactivity half-lives

Various cluster radioactivities of heavy nuclei have been investigated by using the unified fission model (UFM). The cluster preformation factors have been extracted by employing the UFM connected with the experimental half-lives, and the relationship of preformation probability between the cluster and alpha-particle has been discussed in detail. In addition, the cluster preformation probability has been studied in the framework of statistical physics. Some useful predictions on the cluster emission half-lives are provided for future experiments.

alpha-decay half-lives of superheavy nuclei and general predictions

The generalized liquid drop model (GLDM) and the cluster model have been employed to calculate the alpha-decay half-lives of superheavy nuclei (SHN) using the experimental alpha-decay Q values. The results of the cluster model are slightly poorer than those from the GLDM if experimental Q values are used. The prediction powers of these two models with theoretical Q values from Audi et al. (Q(Audi)) and Muntian et al. (Q(M)) have been tested to find that the cluster model with Q(Audi) and Q(M) could provide reliable results for Z > 112 but the GLDM with Q(Audi) for Z <= 112. The half-lives of some still unknown nuclei are predicted by these two models and these results may be useful for future experimental assignment and identification.

Properties and structure of N = Z nuclei within relativistic mean field theory

The axially deformed relativistic mean field theory with the force NLSH has been performed in the blocked BCS approximation to investigate the proper-ties and structure of N=Z nuclei from Z=20 to Z=48. Some ground state quantities such as binding energies, quadrupole deformations, one/two-nucleon separation energies, root-mean-squaxe (rms) radii of charge and neutron, and shell gaps have been calculated. The results suggest that large deformations can be found in medium-heavy nuclei with N=Z=38-42. The charge and neutron rms radii increase rapidly beyond the magic number N=Z=28 until Z=42 with increasing nucleon number, which is similar to isotope shift, yet beyond Z=42, they decrease dramatically as the structure changes greatly from Z=42 to Z=43. The evolution of shell gaps with proton number Z can be clearly observed. Besides the appearance of possible new shell closures, some conventional shell closures have been found to disappear in some region. In addition, we found that the Coulomb interaction is not strong enough to breakdown the shell structure of protons in the current region.

STUDY ON THE SPATIAL PATTERNS OF LAND-USE CHANGE AND ANALYSES OF DRIVING FORCES IN NORTHEASTERN CHINA DURING 1990-2000

Land-use change is an important aspect of global environment change. It is, in a sense, the direct result of human activities influencing our physical environment. Supported by the dynamic serving system of national resources, including both the environment database and GIS technology, this paper analyzed the land-use change in northeastern China in the past ten years (1990 - 2000). It divides northeastern China into five land-use zones based on the dynamic degree (DD) of land-use: woodland/grassland - arable land conversion zone, dry land - paddy field conversion zone, urban expansion zone, interlocked zone of farming and pasturing, and reclamation and abandoned zone. In the past ten years, land-use change of northeastern China can be generalized as follows: increase of cropland area was obvious, paddy field and dry land increased by 74. 9 and 276. 0 thousand ha respectively; urban area expanded rapidly, area of town and rural residence increased by 76. 8 thousand ha; area of forest and grassland decreased sharply with the amount of 1399. 0 and 1521. 3 thousand ha respectively; area of water body and unused land increased by 148. 4 and 513. 9 thousand ha respectively. Besides a comprehensive analysis of the spatial patterns of land use, this paper also discusses the driving forces in each land-use dynamic zones. The study shows that some key biophysical factors affect conspicuously the conversion of different land- use types. In this paper, the relationships between land- use conversion and DEM, accnmlated temperature(>= 10 degrees C) and precipitation were analysed and represented. We conclude that the land- use changes in northeast China resulted from the change of macro social and economic factors and local physical elements. Rapid population growth and management changes, in some sense, can explain the shaping of woodland/grassland - cropland conversion zone. The conversion from dry land to paddy field in the dry land - paddy field conversion zone, apart from the physical elements change promoting the expansion of paddy field, results from two reasons: one is that the implementation of market-economy in China has given farmers the right to decide what they plant and how they plant their crops, the other factor is originated partially from the change of dietary habit with the social and economic development. The conversion from paddy field to dry land is caused primarily by the shortfall of irrigation water, which in turn is caused by poor water allocation managed by local governments. The shaping of the reclamation and abandoned zone is partially due to the lack of environment protection consciousness among pioneer settlers. The reason for the conversion from grassland to cropland is the relatively higher profits of fanning than that of pasturing in the interlocked zone of farming and pasturing. In northeastern China, the rapid expansion of built-up areas results from two factors: the first is its small number of towns; the second comes from the huge potential for expansion of existing towns and cities. It is noticeable that urban expansion in the northeastern China is characterized by gentle topographic relief and low population density. Physiognomy, transportation and economy exert great influences on the urban expansion.

冀东油田柳南地区新近系油藏剩余油形成及分布规律研究

This thesis is based on the research project of Study on the Geological Characteristics and Remaining Oil Distribution Law of Neogene Reservoirs in Liunan Area, which is one of the key research projects set by PetroChina Jidong Oilfield Company in 2006. The determination of remaining oil distribution and its saturation changes are the most important research contents for the development and production modification of oilfields in high water-cut phases. Liunan oilfield, located in Tangshan of Hebei Province geographically and in Gaoliu structural belt of Nanpu sag in Bohai Bay Basin structurally, is one of the earliest fields put into production of Jidong oilfield. Focusing on the development problems encountered during the production of the field, this thesis establishes the fine geological reservoir model through the study of reservoir properties such as fine beds correlation, sedimentary facies, micro structures, micro reservoir architecture, flow units and fluid properties. Using routine method of reservoir engineering and technology of reservoir numerical modeling, remaining oil distribution in the target beds of Liunan area is predicted successfully, while the controling factors of remaining oil distribution are illustrated, and the model of remaining oil distribution for fault-block structure reservoirs is established. Using staged-subdivision reservoir correlation and FZI study, the Strata in Liunan Area is subdivided step by step; oil sand body data-list is recompiled; diagram databases are established; plane and section configuration of monolayer sandstone body, and combination pattern of sandstone bodys are summarized. The study of multi-level staged subdivision for sedimentary micro-facies shows that the Lower member of Minghuazhen formation and the whole Guantao formation in Liunan Area belong to meandering river and braided river sedimentary facies respectively, including 8 micro facies such as after point bar, channel bar, channel, natural levee, crevasse splay, abandoned channel, flood plain and flood basin. Fine 3D geological modeling is performed through the application of advanced software and integration of geological, seismic logging and reservoir engineering data. High resolution numerical simulation is performed with a reserve fitting error less than 3%, an average pressure fitting fluctuation range lower than 2Mpa and an accumulate water cut fitting error less than 5%. In this way, the distribution law of the target reservoir in the study area is basically recognized. Eight major remaining oil distribution models are established after analysis of production status and production features in different blocks and different layers. In addition, fuzzy mathematics method is used to the integreted evaluation and prediction of abundant remaining oil accumulation area in major production beds and key sedimentary time units of the shallow strata in Liunan Area and corresponding modification comments are put forward. In summary, the establishment of fine reservoir geological model, reservoir numerical simulation and distribution prediction of remaining oil make a sound foundation for further stimulation of oilfield development performance.