EXPERIMENTAL STUDIES OF TARGETING THERAPY OF GASTRIC CANCER WITH ^(131)-I LABELED McAbs

To investigate the radioimmunotherapeutic efficacy, radio-immunoconjugate 131-I-3G9, 811-I-3H11 and 131-I-NMIgG (irre levant antibody) were i.p. injected into nude mice bearing human gastric cancer xenograftes. Each animal received a single doses of 555MBq. Over 14 days the accumulative absorbed doses in tumors were 13.7 Gy for 131-I-3H11 and 12.17 Gy for 131-I-3G9. Both were significantly higher than that for 131-I-NMIgG (3.23 Gy). Thera peutic efficacy appeared most sharply from 2 to 3 weeks after injection. The inhibition ratio of tumor were 86% and 70% for 131-I-3H11 and 131-I-3G9 respectively. Histopathological evidance indicated that in tumor tissues radioactive damage was showed as karyopyknosis, karyorrhexis and necrosis or partial disappearance of tumor cells, while in the other tissues no radioactive damage was observed. WBC counts of all animals did not show significant difference before and after treatment, which indicated that the haemopoietic function of bone marrow was not affected.

Interaction between an Accelerated Mass in Straight Motion and a Hidden Energy Reservoir as a Strict Mathematical Consequence of Special Relativity

A. Einstein and H.A. Lorentz had found that the mass of an accelerated body traveling at relativistic velocity appears to depend on whether the acceleration is performed in the direction of motion or in a transverse direction. E.P. Epstein rejected this result in the “Annalen der Physik”;he rather postulated an additional force that turns up when the body is accelerated in the longitudinal direction. It can be shown that the concept of an increased longitudinal mass is based on a simple mathematical error. When correcting this error, it turns out that Epstein’s additional, hidden force is indispensable in order to avoid an inner inconsistency of Special Relativity. It does most of the total work absorbed by the moving object, and is thus responsible for most of the increase in its energy (=mass), given the speed attained is relativistic. In other words: While the total force on the body needed to maintain a constant acceleration a0 is “(1-v2/c2)-1ma0=m0(1-v2/c2)-3/2a0”, the technical force needed to maintain that acceleration amounts only to “ma0=m0(1 - v2/c2)-1/2a0”. The total energy of two objects that undergo a symmetrical, elastic head-on collision is therefore not conserved during the collision, thus requiring the involvement of a hidden reservoir of energy. This result is confirmed by calculations that use the concept of momenergy. The phenomenon of an apparent disappearance of energy has been noticed in particle physics already (target-experiment), but its consequences have been ignored. Instead, an explanation has been given (reduced “energy of the center of mass”) which is inconsistent and violates the relativity principle.

Experimental researches on underwater target scattering properties in non-incident direction

In the bistatic case, theoretical analysis and experimental researches on underwater acoustic scattering properties of some submarine model are made in this paper. When sourcet target and receiver have complicated triangular configuration, the relationships among target strength, incidence angle and bistatic angle are obtained. The validity of this theory is verified by theoretical calculations and tank experiments. The research results can be directly used in bistatic or multistatic underwater acoustic detection systems.

Prototype studies on the forward MWDC tracking array of the external target experiment at HIRFL-CSR

A prototype of the forward tracking array consisting of three multiwire drift chambers（MWDC） for the external target experiment（CEE） at the Heavy Ion Research Facility at the Lanzhou-Cooling Storage Ring（HIRFL-CSR） has been assembled and tested using cosmic rays. The signals from the anode wires are amplified and fed to a Flash-ADC to deliver the drift time and charge integration. The performances of the array prototype are investigated under various high voltages. For the tracking performances, after the space-time relation（STR）calibration and the detector displacement correction, the standard deviation of 223 μm of the residue is obtained.The performances of the forward MWDCs tracking array meets the requirements of CEE in design.

A Fast Algorithm for Solving CNOP and Associated Target Observation Tests

Conditional Nonlinear Optimal Perturbation （CNOP） is a new method proposed by Mu et al. in 2003, which generalizes the linear singular vector （LSV） to include nonlinearity. It has become a powerful tool for studying predictability and sensitivity among other issues in nonlinear systems. This is because the CNOP is able to represent, while the LSV is unable to deal with, the fastest developing perturbation in a nonlinear system. The wide application of this new method, however, has been limited due to its large computational cost related to the use of an adjoint technique. In order to greatly reduce the computational cost, we hereby propose a fast algorithm for solving the CNOP based on the empirical orthogonal function （EOF）. The algorithm is tested in target observation experiments of Typhoon Matsa using the Global/Regional Assimilation and PrEdiction System （GRAPES）, an operational regional forecast model of China. The effectivity and feasibility of the algorithm to determine the sensitivity （target） area is evaluated through two observing system simulation experiments （OSSEs）. The results, as expected, show that the energy of the CNOP solved by the new algorithm develops quickly and nonlinearly. The sensitivity area is effectively identified with the CNOP from the new algorithm, using 24 h as the prediction time window. The 24-h accumulated rainfall prediction errors （ARPEs） in the verification region are reduced significantly compared with the ＂true state,＂ when the initial conditions （ICs） in the sensitivity area are replaced with the ＂observations.＂ The decrease of the ARPEs can be achieved for even longer prediction times （e.g., 72 h）. Further analyses reveal that the decrease of the 24-h ARPEs in the verification region is attributable to improved simulations of the typhoon＇s initial warm-core, upper level relative vorticity, water vapor conditions, etc., as a result of the updated ICs in the sensitivity area.

A Flash-ADC data acquisition system developed for a drift chamber array and a digital filter algorithm for signal processing

A Flash-ADC data acquisition （DAQ） system has been developed for the drift chamber array designed for the External-Target-Experiment at the Cooling Storage Ring at the Heavy Ion Research Facility, Lanzhou. The simplified readout electronics system has been developed using the Flash-ADC modules and the whole waveform in the sampling window is obtained, with which the time and energy information can be deduced with an offiine processing. A digital filter algorithm has been developed to discriminate the noise and the useful signal. With the digital filtering process, the signal to noise ratio （SNR） is increased and a better time and energy resolution can be obtained.

MicroRNA target prediction based on second-order Hidden Markov Model

MicroRNAs are one class of small singlestranded RNA of about 22 nt serving as important negative gene regulators.In animals,miRNAs mainly repress protein translation by binding itself to the 3'UTR regions of mRNAs with imperfect complementary pairing.Although bioinformatics investigations have resulted in a number of target prediction tools,all of these have a common shortcoming—a high false positive rate.Therefore,it is important to further filter the predicted targets.In this paper,based on miRNA:target duplex,we construct a second-order Hidden Markov Model,implement Baum-Welch training algorithm and apply this model to further process predicted targets.The model trains the classifier by 244 positive and 49 negative miRNA:target interaction pairs and achieves a sensitivity of 72.54%,specificity of 55.10%and accuracy of 69.62%by 10-fold crossvalidation experiments.In order to further verify the applicability of the algorithm,previously collected datasets,including 195 positive and 38 negative,are chosen to test it,with consistent results.We believe that our method will provide some guidance for experimental biologists,especially in choosing miRNA targets for validation.