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Laser altimeters are commonly used in planetary research for their high geodetic accuracy. A key procedure in processing of laser altimeter data is the geolocation. In this process, the time-of-flight measurements are converted to coordinates of laser pulse footprints on the surface of the target body. Here, we present a consistent and systematic formulation of three commonly used geolocation models with increasing complexity: static model, spacecraft motion model, pointing aberration model and special relativity model. We show that for small velocities of the spacecraft relative to the target the special relativity model can be reduced to the pointing aberration model without significant loss in the geolocation accuracy. We then discuss the respective accuracies of the proposed models and apply them to time-of-flight measurements from the Mars Orbiter Laser Altimeter (MOLA) onboard the Mars Global Surveyor (MGS) spacecraft and the Mercury Laser Altimeter (MLA) onboard the MErcury Surface, Space ENvironment, GEochemistry and Ranging spacecraft (MESSENGER). While, the archived datasets had not considered the effect of pointing aberration, we demonstrate that a correction due to pointing aberration makes insignificant improvements of 4–5 m laterally and up to ± 3 cm radially for MOLA profiles, these figures enormously increase to up to about 150 m laterally and ± 25 m radially when applied to the MLA orbital profiles.

It is of significance to evaluate the equivalent contact heat transfer coefficient (ECHTC) at the sheet-die interface in hot stamping of boron steel (HSBS) for controlling the local cooling rate of the sheet and hence obtaining components with tailored microstructure and properties. Moreover, accurate evaluation of the ECHTC can provide a reliable thermal boundary condition for numerical simulation of the HSBS process. In the study, a simple and effective physical simulation setup for die quenching of boron steel (DQBS) was developed, where the temperatures at measurement points are related only to the ECHTC so as to improve the evaluation accuracy. A FE-based optimization model for inverse evaluating the ECHTC was established. The ECHTCs at the B1500HS sheet-H13 die steel interface were identified under various contact pressures, and it was found that the ECHTC increases exponentially with the pressure increasing. Both the physical simulation of DQBS and the HSBS experiment were performed to verify the ECHTC evaluated, and the maximum relative errors of 9.6 and 19.7 % were observed, respectively, between the predicted and measured temperature histories.

Overuse of nitrogen (N) fertilizer constitutes the major issue of current crop production in China, exerting a substantial effect on global warming through massive emission of greenhouse gas (GHG). Despite the ongoing effort, which includes the promotion of technologically sophisticated N management schemes, farmers' N rates maintain at excessive rates. Therefore the current study tests three simple and easily to apply N fertilizer recommendation strategies, which could be implemented on large scale through the existing agricultural advisory system of China, at comparatively low cost. Building on a detailed crop production dataset of 65 winter wheat (WW) and summer maize (SM) producing farm households of the North China Plain, scenario analysis is applied. The effects of the three N strategies under constant and changing yield levels on product carbon footprint (PCF) and gross margin (GM) are determined for the production condition of every individual farm household. The N fixed rate strategy realized the highest improvement potential in PCF and GM in WW; while the N coefficient strategy performed best in SM. The analysis furthermore revealed that improved N management has a significant positive effect on PCF, but only a marginal and insignificant effect on GM. On the other side, a potential 10% yield loss would have only a marginal effect on PCF, but a detrimental effect on farmers' income. With farmers currently applying excessive N rates as "cheap insurance" against potential N limitation, it will be of vital importance to avoid any yield reductions (caused by N limitation) and respective severe financial losses, when promoting and implementing advanced fertilization strategies. To achieve this, it is furthermore recommended to increase the price of fertilizer, improve the agricultural extensions system, and recognize farmers' fertilizer related decision-making processes as key research areas.

Ovarian cancer has the highest mortality rate and is the most common of all gynecologic malignancies. Novel treatments for ovarian cancer are urgently required to improve outcomes and the overall survival of patients. The present study investigated whether immunotherapy with natural killer (NK) cells affected the survival of mice with ovarian cancer. Results analysis identified adjunctive NK cells as a potential therapeutic method in ovarian cancer. Patient-derived ovarian cells were isolated, cultured and subsequently injected subcutaneously into immune deficient BALB/c-nude mice. Human NK cells were isolated from peripheral blood mononuclear cells and cultured for expansion in vitro. The present results demonstrated that ovarian cells in BALB/c-nude mice did not induce spontaneous ovarian cancer cell metastasis in the NK-treated group. In addition, NK cells activated immune cells in the immune system, which resulted in inhibition of ovarian tumor growth in vitro and in a murine xenograft model of ovarian cancer. The data also indicated that cytotoxic activity of NK cells prevented migration and invasion of ovarian cancer cells, which contributed to prevention of systemic metastasis and suggested that NK cells could be effective cells for therapy against ovarian cancer. Furthermore, NK cells induced apoptosis and increased the number of cluster of differentiation (CD)4+, CD8+ as well as cytotoxic T lymphocyte responses by intravenous injection in a murine xenograft model of ovarian cancer. These results suggested that NK cells inhibited the systemic metastasis for ovarian cancer cells. In conclusion, the present study suggested that NK cell immunotherapy inhibited systemic metastasis of ovarian cancer cells and improved the survival rate of mice. Sufficient supplementation of NK cells may serve as a promising immunotherapeutic strategy for ovarian cancer.

The current paper discusses the measure methods and presents the application of acceleration sensors in a stamping press tonnage load monitoring. The forming force is proportion to the distortion of press stressed components, and it can be calculated with double integral from the acceleration signals. Multi-sensors of MEMS are used to obtain the relative signals between the frame body and bottom die base in X, Y and Z-axes directions. Based the acceleration signals, the stages of press stamping process can be distinguished clearly due to the relation tie up the forming force change. The paper introduces a measurement value of the maximum relative distortion and load, then discusses the reasons of error bring in experiments. A principle is proposed to correct the integral results and the experiments prove that the method is doable and the results deviation can be held in an acceptable accuracy limit.

This paper discusses automatic modulation classification (AMC) of analog schemes. Histograms of instantaneous frequency are used as classification features and Support Vector Machines (SVMs) are then applied to classify the unknown modulation schemes. This novel machine-learning based method can insure robustness in a wide range of SNR. Extensive simulation has demonstrated the validity of the proposed AMC algorithm. It is a practical algorithm in blind AMC environments.

Polycyclic aromatic hydrocarbons (PAHs) in a sediment core from the north Lianhuan Lake were collected to investigate its historical changes in the last one hundred years and its possible influence on ecological system in the lake. GC-MS was used to determine the concentrations of PAHs, and sediment chronological age was examined by (137)Cs dating approach. The concentrations of 16 different kinds of PAHs in the sediment samples ranged from 297 to 1,327 ng g(-1), and the low molecular weight (LMW) were predominant. The intensification of industrial and anthropogenic activities in the Daqing oil field may play the key role in the increase of PAHs concentrations in the late 1950s. To the early 1980s, the PAHs concentrations significantly decreased due to the grain size coarsening in the sediment samples, which was confirmed by the precipitation information. The 5-6 rings PAHs concentrations increased in the early 1980s may be attributed to the consumption of petroleum, coal and wood. The results showed that both the PAHs historical record and current concentrations may cause some influence on the Lianhuan Lake ecological system. The toxicology research on this ecological system should be done in the further investigations for determining the PAHs damage on human and ecological system health.

This paper presents an effective carrier frequency estimation algorithm for adaptive demodulation of SSB-SC signals based on software defined radios. Higher-order moments are used for accurate carrier frequency estimation without a priori physical layer knowledge or a pilot tone associated with the received signal. Experiment results demonstrate the good performance of the algorithm.

Liver cancer is the fifth most common cancer caused deaths worldwide and its incidence is increasing. The factors that influence the liver cancer progression are not clear. Recent reports show heme oxygenase-1 (HO-1) plays an important role in tumor progression and metastasis. Therefore, study the mechanism of HO-1 in liver cancer could potentially understand the liver cancer development and metastasis. We established two liver cancer cell lines that either contains wild- or mutant-type HO-1 gene to study the role of HO-1 in liver cancer metastasis. Matrigel invasion chambers assay was used to determine the invasion and migration of cells. The expression of IL-6, which is the key regulator of HO-1, was analyzed by real-time RT-PCR and ELISA for mRNA and protein, respectively. Two target-specific MMP and RGD peptides imaging agents were synthesized to follow up the liver cancer growth. Imaging studies were performed in cancer cells and xenograft models. In vivo imaging studies (n=10) were performed with peptide imaging agents and 18F fluoro-deoxy-glucose (18F-FDG) using optical, CT and PET scanning. The data demonstrated that overexpression of HO-1 significantly decreased the invasion ability of the liver cancer cells (P *CZ, WW: These authors contributed equally to this work. Grant support: DoD W81XWH-08-1-0489 (SK, WW), Department of Radiology research fund (SK, WW, MEM), National Science Foundation of China Grants 81000933 (CZ), Major State Basic Research Development Program of China 973 Program 2009CB521702 (XG). Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5300. doi:10.1158/1538-7445.AM2011-5300