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A survey was carried out on doctoral students in the U.S. from eleven disciplines and twenty-seven universities to find the impact of the satisfaction of doctoral students with their advisors as instrumental in completing their doctoral training.

The reinvestigation of the n-BuOH extract of the roots of Clematis argentilucida led to the isolation of four new oleanane-type triterpenoid saponins, 1-4, four known saponins, 5-8, first isolated from the species, together with ten saponins, 9-18, reported in the preceding papers. The structures of saponins 1-8 were elucidated by extensive spectroscopic analysis and chemical evidences. The cytotoxicity of all the saponins were evaluated against human tumor HL-60, HepG-2, and SGC-7901 cell lines. The monodesmosidic saponins 4, 7, 8,a n d 14-18 exhibited cytotoxic activity against the three cell lines with IC50 values in the range of 0.87-19.48 µM. [ABSTRACT FROM AUTHOR]

A stencil printing process (SPP) optimization problem is studied in this paper. Due to the limitation that neural network requires a large number of samples for the accurate model fitting, a two-stage SPP optimization method is proposed. The design interval can be reduced with small sample by using neural network. In this reduced design interval , response surface method is adopted to obtain the accurate mathematical SPP model. The concept of confidence level is introduced to make the proposed model robust. An interactive method is used to solve the model. The proposed method is compared with the one-stage optimization method and the results show that the proposed method achieves a better performance on each objective.

Intramuscular fat (IMF) content is an important determinant of quality characteristics such as tenderness, juiciness and flavour, and of its acceptability by consumers. Research has therefore focused on improving meat quality by optimizing IMF. The present review describes evidence from studies of physiology, biochemistry, cell biology, genetics, candidate genes and nutritional regulation as well as animal trials relating to pig meat IMF and meat quality. Recent evidence suggests that breed and marker-assisted selection, candidate genes and nutritional regulation are the most promising strategies for improving IMF content. Additionally, some important aspects of IMF content research and related patents are also discussed.

A novel cyclic ether monomer 3‐{2‐[2‐(2‐hydroxyethoxy)ethoxy]ethoxy‐methyl}‐3′‐methyloxetane (HEMO) was prepared from the reaction of 3‐hydroxymethyl‐3′‐methyloxetane tosylate with triethylene glycol. The corresponding hyperbranched polyether (PHEMO) was synthesized using BF3·Et2O as initiator through cationic ring‐opening polymerization. The evidence from 1H and 13C NMR analyses revealed that the hyperbranched structure is constructed by the competition between two chain propagation mechanisms, i.e. active chain end and activated monomer mechanism. The terminal structure of PHEMO with a cyclic fragment was definitely detected by MALDI‐TOF measurement. A DSC test implied that the resulting polyether has excellent segment motion performance potentially beneficial for the ion transport of polymer electrolytes. Moreover, a TGA assay showed that this hyperbranched polymer possesses high thermostability as compared to its liquid counterpart. The ion conductivity was measured to reach 5.6 × 10−5 S/cm at room temperature and 6.3 × 10−4 S/cm at 80 °C after doped with LiTFSI at a ratio of Li:O = 0.05, presenting the promise to meet the practical requirement of lithium ion batteries for polymer electrolytes. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3650–3665, 2006

Focuses on the evolvement of health care in rural cities in China from the 1940s-1990s. Information on cooperative medical care pertaining to change; Details on the ensuring of proper use of medical care fund in Tai'an; Examination of the training of the medical workers in rural clinics.

Two human hepatoma cell lines, QGY-7703 and SMMC-7721, and two human pulmonary adenocarcinoma cell lines, LTEP-a-2 and SPC-A-1, were found to respond to 1 μg/mL Na2SeO3, 24 h, in-vitro treatment by decreasing its confluent saturation density. The same treatment was found to cause an increase in the adhesiveness of cells measured as resistance to detachment by trypsin/EDTA. The pathological features of tumors after heterotransplantation of treated and untreated cells were similar, but the size of tumor grown from treated cells was much smaller.

The effect of different concentrations of Na2SeO3on human pulmonary adenocarcinoma cells and human embryonic lung diploid cells in vitro was investigated. For human pulmonary adenocarcinoma cells, mitotic index and cell count decreased with increasing selenium concentrations. At 1 μg/mL sodium selenite, mitotic activity and growth of human lung cancer cells were partially inhibited, and the progression of human lung cancer cell cycle was partially arrested. When human embryonic lung diploid cells were treated with 1 μg/mL sodium selenite for five continuous days, cell counts of the treated group were closely parallel to those of the control group. After treating human embryonic lung diploid cells with 1–5μg/mL sodium selenite for 1–3 d, the mitotic index (MI), labeled index (LI), and average silver grain (SG) number per 20 labeled nuclei were the same as those of the control. In mixed cultures of human embryonic lung diploid cells and human pulmonary adenocarcinoma cells, treated with 3 and 5 μg/mL sodium selenite for 24 h, the lung diploid cells showed a normal fusiform morphology, whereas the lung cancer cells showed heavily vacuolated cytoplasms and distorted nuclei.

The effects of various concentrations of Na2SeO3on human hepatoma cells and human embryonic liver cells was investigated in vitro. For human hepatoma cells, mitotic index and cell count decreased with increasing selenium concentrations. At 1 μg/mL Na2SeO3, mitotic activity of human hepatoma cells were partially arrested. In human embryonic liver cells continuously treated with Na2SeO3, (1 μg/mL) cell count of the treated group decreased only by d 7; mitotic index, labeled index, and mean silver grain number per 50 labeled nuclei were the same as in the control group on exposure to 1, 3, and 5 μg/mL for up to 72 h. In mixed cultures of human hepatoma and embryonic liver cells treated with 3 and 5 μg/mL of Na2SeO3for 24 h, hepatoma cells showed vacuolated cytoplasms, distorted nuclei, condensed chromatin, and even pyknosis, whereas the embryonic liver cells retained a normal morphology under the same treatment.

Twenty cases of infantile eczema were treated by combination of Tuina therapy and Western medications, and 18 cases were treated by Western medications. The therapeutic effective rate was respectively 100% and 90.0% in the two groups, with a difference between them (P<0.01).

We present two realistic entanglement concentration protocols (ECPs) for pure partially entangled photons. A partially entangled photon pair can be concentrated to a maximally entangled pair with only an ancillary single photon with a certain probability, while the conventional ECPs require two copies of partially entangled pairs at least. Our first protocol is implemented with linear optics and the second protocol is implemented with cross-Kerr-nonlinearities. Compared with other ECPs, they do not need to know the accurate coefficients of the initial state. With linear optics, it is feasible with current experiments. With cross-Kerr-nonlinearities, it does not require sophisticated single-photon detectors and can be repeated to get a higher success probability. Moreover, the second protocol can get the higher entanglement transformation efficiency and it may be the most economical protocol by far. Meanwhile, both protocols are more suitable for multiphoton system concentration because they need less operations and classical communications. All these advantages make the two protocols useful in current long-distance quantum communications. [ABSTRACT FROM AUTHOR]