Quantitative analysis of pheromone production in irradiated Caribbean fruit fly males,Anastrepha suspensa (Loew)

Pheromonal volatiles emitted by irradiated and control 5- to 11-day-old Caribbean fruit flies,Anastrepha suspensa (Loew), were collected on Tenax adsorbent filters and quantified by gas chromatography (GC). The components released were identified by comparison of retention times on GC and by mass spectrometry (MS) with authentic synthetic standards. Pharate adults were irradiated with gamma rays from a⁶⁰Co source at a dose rate of 10.3 Gray (Gy)/min. The total dosages given were 30, 50, 70, and 100 Gy. Pheromone volatiles were collected from adult males when they were between 5 and 11 days of age. The compounds quantified were (Z)-3-nonenol and (Z, Z)-3,6-nonadienol, which eluted from the GC column together and were quantified as one peak,h756j4055313/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-bisabolene, suspensolide, anastrephin, and epianastrephin. Irradiation with 30 Gy did not significantly reduce any pheromonal components, nor did it change the pheromonal blend. In contrast, suspensolide and bisabolene were significantly reduced in flies irradiated with 50 Gy, while the nonenols and epianastrephin were reduced at the 70-Gy dose. Irradiation with the 100-Gy dose reduced all components with the exception of suspensolide.University of Florida Agric. Exper. Sta. Journal Series No.R-03156.     

The historical workstation project

Since 1978 research in the development of software dedicated to the specific problems of historical research has been undertaken at the Max-Planck-Institute für Geschichte in Göttingen. From a background of practical experiences during these years, a concept of what an appropriate h8q821/xxlarge8216.gif" alt="lsquo" align="BASELINE" BORDER="0">workstationh8q821/xxlarge8221.gif" alt="rdquo" align="MIDDLE" BORDER="0"> for an historian would be has been derived. It stresses the necessity of three components: (a) software, derived from a detailed analysis of what differentiates information contained in historical sources from such present in current material, (b) databases which are as easily available as printed books and (c) knowledge bases which allow software and data bases to draw upon the information contained in historical reference works. A loose network of European research projects, dedicated to the realization of such a setup, is described.Manfred Thaller has a Ph.D. (1975) in Modern and Medieval History and held a post-doctoral fellowship in sociology at the Institute for Advanced Studies (Vienna). Since 1978 he has been at the Max-Planck-Institute for History, where he is a research fellow for Historical Information Science.     

Texture analysis of poly-adenylated mRNA staining following global brain ischemia and reperfusion

Texture analysis provides a means to quantify complex changes in microscope images. We previously showed that cytoplasmic poly-adenylated mRNAs form mRNA granules in post-ischemic neurons and that these granules correlated with protein synthesis inhibition and hence cell death. Here we utilized the texture analysis software MaZda to quantify mRNA granules in photomicrographs of the pyramidal cell layer of rat hippocampal region CA3 around 1 h of reperfusion after 10 min of normothermic global cerebral ischemia. At 1 h reperfusion, we observed variations in the texture of mRNA granules amongst samples that were readily quantified by texture analysis. Individual sample variation was consistent with the interpretation that animal-to-animal variations in mRNA granules reflected the time-course of mRNA granule formation. We also used texture analysis to quantify the effect of cycloheximide, given either before or after brain ischemia, on mRNA granules. If administered before ischemia, cycloheximide inhibited mRNA granule formation, but if administered after ischemia did not prevent mRNA granulation, indicating mRNA granule formation is dependent on dissociation of polysomes. We conclude that texture analysis is an effective means for quantifying the complex morphological changes induced in neurons by brain ischemia and reperfusion.     

Unconventional Field Dependence of Magnetoresistance of (TMTSF)2ClO4 Studied by 46-T Pulsed Magnetic Field System

A new TTP donor, Me-DH-TTP (2-methyl-5-(1,3-dithiolan-2-yliden)-1,3,4,6-tetrathiapentalene), was designed to realize a system with large on-site Coulomb repulsion as compared with the previously known bis-fused type TTP donors. Probably as a consequence, (Me-DH-TTP)₂AsF₆ exhibits semiconducting behavior from room temperature to liquid helium temperature. By increasing pressure, metallic behavior appears below 300 K, and with distinct metal-insulator (M-I) transition up to 2.2 GPa. This M-I transition suddenly disappears beyond 2.5 GPa, and metallic state is stabilized down to 2.6 K. We discuss the possibility of quantum critical point around 2.4 GPa.     

Role of frustration in quasi 1D conductor — Charge ordering and/or CDW in (R1,R2-DCNQI)2M (M=Ag, Li, Cu) system —

Synchrotron X-ray high-resolution measurements have been performed to investigate the nature of the insulating state of a quarter-filled quasi-one-dimensional conductor (DI-DCNQI)₂Ag and the π-d interacted conductor (DBr-DCNQI)₂Cu. The two-fold structure in the ground state of (DI-DCNQI)₂Ag system consists of not only charge ordering columns but also monotonic charge dimerized columns caused by frustration among DCNQI columns. On the other hand, Cu salt in the insulating phase realizes a commensurate structure where the Cu charge ordering is coupled with the 3c-CDW in the insulator phase. The frustration among charged columns is restrained by the charge ordering of the Cu ions.     

Work function variations of incandescent filaments during self-cooling in vacuum

A novel method of dynamic measurement of work function (WF) variations of hot metal filaments is described. It is essential in this method that electron emission current (I_e) is recorded during filament self-cooling when no heating power is supplied, thereby I_e is not disturbed by the potential gradient along the filament. WF shift due to the presence of a low-pressure gas, where the main active compounds are O₂ and H₂O, is calculated from an equation derived on the basis of the Richardson formula. The relative increase of WF found by this method was 5 times larger for tungsten than that for tantalum over the entire temperature range from 900 to 1800 K. Our method may be used in research studies of adsorption-related phenomena on metallic surfaces at high temperatures.     

叠层材料振动钻削的计算机仿真

以灰色系统理论为基础,将GM(1,h)模型应用于叠层材料变参数振动钻削过程的仿真,运用灰关联度分析方法研究了叠层材料振动钻削过程中的振动频率、振幅、进给量等输入参数对工艺效果的影响,获得了钻削效果影响因素的显著性次序。理论分析和实验结果表明,用GM(1,h)模型进行仿真,建模方便、计算简单。为叠层材料振动钻削研究提供了新的方法和途径。     

Improved single neuron controller for multivariable stochastic systems with non-Gaussianities and unmodeled dynamics

In this paper, a new adaptive control approach is presented for multivariate nonlinear non-Gaussian systems with unknown models. A more general and systematic statistical measure, called (h,?)h altimg="si0004.gif" overflow="scroll">hy="false">(h,?hy="false">)h>-entropy, is adopted here to characterize the uncertainty of the considered systems. By using the “sliding window” technique, the non-parameter estimate of the (h,?)h altimg="si0005.gif" overflow="scroll">hy="false">(h,?hy="false">)h>-entropy is formulated. Then, the improved neuron based controllers are developed for multivariate nonlinear non-Gaussian systems by minimizing the entropies of the tracking errors in closed loops. The condition to guarantee the strictly decreasing entropy of tracking error is presented. Moreover, the convergence in the mean-square sense has been analyzed for all the weights in the neural controllers. Finally, the comparative simulation results are presented to show that the performance of the proposed algorithm is superior to that of PID control strategy.     

除氧器用1200t／h喷嘴的国产化

考虑了除氧器给水高含氧量及除氧器内部高温加快腐蚀速率的特点,结合喷嘴关键核心零件碟片的加工方法进行合理选材,并提出材料防腐表面处理要求。经过疲劳试验验证碟片的使用寿命能满足除氧器设计寿命30年的需要。将喷嘴中滤网从啧嘴下部移到喷嘴入口处,使检修、清理方便,在喷嘴下部设计了4个支撑点,使喷嘴在安装、检修时的安放更为稳固。     

Bystander effect in human hepatoma HepG2 cells caused by medium transfers at different times after high-LET carbon ion irradiation

Although radiation-induced bystander effects have been well documented in a variety of biological systems, whether irradiated cells have the ability to generate bystander signaling persistently is still unclear and the clinical relevance of bystander effects in radiotherapy remains to be elucidated. This study examines tumor cellular bystander response to autologous medium from cell culture irradiated with high-linear energy transfer (LET) heavy ions at a therapeutically relevant dose in terms of clonogenic cell survival. In vitro experiments were performed using human hepatoma HepG2 cell line exposed to 100 keV/μm carbon ions at a dose of 2 Gy. Two different periods (2 and 12 h) after irradiation, irradiated cell conditioned medium (ICCM) and replenished fresh medium were harvested and then transferred to unirradiated bystander cells. Cellular bystander responses were measured with the different medium transfer protocols. Significant higher survival fractions of unirradiated cells receiving the media from the irradiated cultures at the different times post-irradiation than those of the control were observed. Even replenishing fresh medium for unirradiated cells which had been exposed to the ICCM for 12 h could not prevent the bystander cells from the increased survival fraction. These results suggest that the irradiated cells could release unidentified signal factor(s), which induced the increase in survival fraction for the unirradiated bystander cells, into the media sustainedly and the carbon ions triggered a cascade of signaling events in the irradiated cells rather than secreting the soluble signal factor(s) just at a short period after irradiation. Based on the observations in this study, the importance of bystander effect in clinical radiotherapy was discussed and incorporating the bystander effect into the current radiobiological models, which are applicable to heavy ion radiotherapy, is needed urgently.