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To allow different organizations to jointly use PCA for dimensionality reduction and data release under the premise of protecting the privacy of local sensitive data and the data released after dimensionality reduction, this paper proposed a horizontal federated PCA differential privacy data publishing algorithm. It introduced a random seed joint negotiation scheme to generate the same noise matrix between sites with less communication cost. It proposed a local noise averaging scheme, and added the averaging noise to the local covariance matrix. On the one hand, it protected local data privacy. On the other hand, it reduced the amount of noise added and achieved the same noise level as the centralized differential privacy PCA algorithm. Compared with similar algorithms, the amount of noise added was reduced. The experiment evaluates the algorithm from the perspective of privacy and utility, and proves that the algorithm has higher utility compared with similar algorithms. [ABSTRACT FROM AUTHOR]

In differential privacy histogram publication the privacy budget involves the intensity of noise adding, which has a direct impact on the availability of data publication. Therefore, how to allocate and optimize the privacy budget is a challenge to the histogram publishing algorithm. This paper proposed a histogram publishing algorithm based on adaptive privacy budget allocation strategy, called APB. In order to balance the noise error and reconstruction errorefficiently and get the relations hip between the privacy budget allocation weight and the group size and number of group, APB established an optimization model of privacy budget allocation weight by analyzing the noise introduced before and after the grouping step. In order to boost the accuracy of the released histogram, this paper employed optimization model and greedy grouping to propose an adaptive privacy budget allocation strategy. Experimental results show that the proposed method of histogram publication based on adaptive privacy budget allocation strategy is more available than similar algorithms. [ABSTRACT FROM AUTHOR]

The collision between India Plate and Asia Plate has a strong impact on the deformation of the orogenic belts and basins in the western China， especially much of the deformation is centered on the internal Tarim Basin with the rigid basement，which is mainly in and both sides of Bachu uplift. The northtoward Mazatage arcuate structure in map-view， which is located in the southern deformation sides of Bachu uplift， is covered by Quaternary sedimentary terrestrial clastic rocks. The poor reflection of the seismic data in the both limbs nearby the core of Mazatage anticline has given many structural interpretations of Mazatage structural belt，because the wells， mainly located in the cores of Mazatage anticline， are relatively shallower and unrevealed deeper strata. The Mazatage actuate structural belt can be divided into three parts in map， including the northeastward west part， the east-westward middle part and the northwestward east part，which were respectively separated by Ma7-well lateral ramp and a transversal Ma4-well strike-slip fault. By wells and 2D seismic data，the reinterpreted seismic data show Mazatage anticline is a typical mid-Cambrian-gypsum-cored detachment folds both in the western part and central part of Mazatage arcuate structure with thrusting northward，in which two thrust faults are developed in both the core and in south limb of the anticline. According to the structural styles in detail, it is found that a mid-Cambrian-gypsum-cored Mazatage detachment anticline restored by removing thrust faults shows a shortening of Cambrian-Ordovician is greater than that of Carboniferous-Permian，and can be interpreted a simple shear fault-bend fold resulted by both Mazatage thrust and Gudongshan thrust fault with strike-slip shear faulting in the north limb of anticline in the west part of Mazatage arcuate structure. In the eastern part of Mazatage arcuate structures，an anticline is developed by North Mazatage thrust fautt with strike-slip shear faulting in the south limb of anticline，and can be interpreted a simple shear fault-bend fold. The section restored by removing thrust faults illustrates that the shortening from Early-Middle Cambrian to Late Ordovician increases greatly, but decreases gradually from Carbonic to Late Permian. The detached Mazatage anticline restored by removing thrust faults shows that the shorting of Paleozoic strata from Permian to Cambrian is not changed in the central part without shearing in the north limb of anticline. The interpretation of seismic data shows that there is a sinistral component of transcurrent movement added to the north thrusting in the western part of Mazatage arcuate structures, and a dextral component of transcurrent movement added to the north thrusting in the eastern part. [ABSTRACT FROM AUTHOR]

The sidewall contact device of CMRT was broken; the pusher head and the screw broken. Through the macro and micro analysis of the fracture surface, it is determined that the failure mode of the push head is cleavage fracture, and that of the screw is fatigue fracture. The chemical compositions of the two cracked parts meet the technical requirements of 17-4PH.The hardness value of the pusher head meets the standard requirements, and the hardness value of the screw is lower than the standard requirements. The results of metallographic structure analysis show that both contain δ-ferrite except normal martensite. Based on the physical and chemical test results and the structural characteristics of the thruster, the screw is determined to be the initial fragment. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of interference of Sema4D expression on cell biological behavior in pancreatic cancer. MethodsSema4D-siRNA was designed, synthesized, and transfected into a human pancreatic cancer cell line. The cells were divided into siRNA transfection group, negative control group (nonspecific transfection group), and blank control group (untreated pancreatic cancer cells). RT-qPCR was used to measure the change in the mRNA expression of Sema4D at 48 hours after transfection, and Western blot was used to measure the change in the protein expression of Sema4D at 72 hours after transfection. MTT assay was used to observe the change in cell growth after transfection, Transwell chamber invasion assay was used to observe the change in tumor cell invasion after transfection, and flow cytometry was used to observe the change in the apoptosis of tumor cells. An analysis of variance was used for comparison between multiple groups, and the least significant difference t-test was used for further comparison between any two groups. ResultsAt 48 hours after Sema4D-siRNA transfection, the siRNA transfection group had significantly lower mRNA expression of Sema4D than the negative control group and the blank control group (F=421.990, P＜0.001). At 72 hours after Sema4D-siRNA transfection, the siRNA transfection group had significantly lower protein expression of Sema4D than the negative control group and the blank control group (F=27.074, P=0.002 3). At 48, 72, and 96 hours after transfection, the siRNA transfection group had a significantly lower cell growth rate than the negative control group and the blank control group (F=15.314, 62.255, and 223.493, P=0.004, ＜0.001, and ＜0.001). The siRNA transfection group had a significantly lower number of cells which crossed the membrane than the negative control group and the blank control group (42.0±5.9 vs 60.0±6.1 vs 61.0±4.6,F=37.21, P=0.000 4). The siRNA transfection group had a significantly lower apoptosis rate than the negative control group and the blank control group ［(16.57±0.31)% vs (9.50±0.45)% vs (9.90±0.61)%，F=26.75，P=0.007 4］. ConclusionSema4D-siRNA can downregulate the expression of Sema4D in pancreatic cells and can inhibit the proliferation of pancreatic cancer cells and reduce their invasion ability and apoptosis. [ABSTRACT FROM AUTHOR]