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Based on the research of other major foreign petroleum companies management process and evaluating the characteristics of operation for overseas petroleum projects, the portfolio optimization workflow for overseas petroleum investment was established; The multi-objective optimization model considering multiple objectives and constraints such as production, investment capital, IRR, project risk, and NPV was established. Four optimized portfolio cases were separately analyzed. By proposing the strategies of postponing some projects to build capacity, selling the part of working interests or quitting whole projects, and purchasing some new projects, the requirements of multi-objective planning were ultimately satisfied. The results and suggestions can provide a theoretical basis for the decision choices of overseas petroleum investment.

Quercetin (Q) is one of the most common flavonoids present in roots, stems, leaves, flowers and fruits of most plants. In this study, a quercetin-based fluorescent probe for detecting fluorid ions had been proposed. With good selectivity and sensitivity for fluorid ions, Q-based fluorescent probe was easier to prepare, more eco-friendly and more innoxious compared with traditional fluorescent probe obtained by organic chemistry synthesis operation. There was a major fluorescence emission peak at 500 nm for Q in dimethyl sulfoxide (DMSO) when the excitation wavelength was 390 nm. The changes of fluorescence spectra were investigated before and after adding different anions into Q solution. The fluorescence emission intensity of Q even had no change when adding Cl-，Br-，I-，ClO-4，H2PO-4, respectively. While adding fluorid ions, the fluorescence emission intensity of Q was decreased obviously, which suggested fluorid ions could induce fluorescence quenching of Q in DMSO. And the fluorescence emission intensity of Q-F- system had almost no significant change when adding other anions (Cl-，Br-，I-，ClO-4，H2PO-4), which meant the progress for detecting fluorid ions didn’t be affected by other anions, and Q showed a good selectivity for fluorid ions. The fluorescence titration spectra showed that the fluorescence emission intensity of Q was decreased with the increase of concentration of fluorid ions, and they were in concentration-dependent manner. The fluorescence titration curve exhibited that the Q as fluorescent probe can be applied to the quantification of fluorid ions with a good linearity (R2=0.991), linear range of 1.0～8.0×10-6 mol·L-1 and the detection limit of 1.0×10-7 mol·L-1. Not only the changes appeared in fluorescence spectra, but also the changes appeared in UV-visible spectra, compared with Q absorption spectrum, the location of band at 375 nm had no change after adding Cl-，Br-，I-，ClO-4，H2PO-4, respectively. However, when adding fluorid ions, the band at 375 nm was shifted to 394 nm, and the color of the solution was changed into dark yellow, which revealed the interactions between Q and fluorid ions. The probable mechanism of fluorid ions inducing fluorescence quenching of Q was obtained with 1H NMR spectrum and the changes of fluorescence emission intensity of Q-F- system in different polar solvents (DMSO containing different concentration of water). The interaction mode about Q and fluorid ions in DMSO was related with hydrogen bond. Both experiments suggested that the possible recognition mechanism on fluorid ions was: fluorid ions were destroyed or weakened by original hydrogen bonds, and were promoted charge transfer within quercetin molecule, which resulted in fluorescence intensity decreasing of quercetin. This method was successfully applied in detecting fluorid ions of samples in DMSO with good recovery.

Objective OTUB1 is a member of deubiquitinating enzymes; however, its expression and function in colon cancer are still unclear. The present study aimed at investigating the expression of OTUB1 in colon cancer and the relationship between the expression and some clinicopathologic parameters. Methods Immunohistochemistry and quantitative real-time PCR were carried out in selected colon cancer and normal mucosa tissues. Results The expression of OTUB1 protein in the colon cancer was significantly higher than normal mucosa, and the OTUB1 mRNA in colon cancer was also 3.15-fold higher than the normal mucosa. The higher expression of OTUB1 in colon cancer was related with tumor size, differentiation and lymph node metastasis. Conclusions OTUB1 may play an important role in colon cancer development and metastasis.

Markowitz’s portfolio selection theory was applied in overseas petroleum venture capital investment, the mean of each project’s AT cash was used as the portfolio’s return, the fluctuate rate return of project was used to reflect portfolio’s risk, the combination of minimum risk portfolio optimization decision model was established. A variety of risk definition method were explored, efficient frontier under variety of risk-defined were developed, according to different risk preferences, the investment decision-makers can choose optimal portfolio to maximize investment, so as to reduce and avoid undue loss.

Background: OTUB1 is a new member of ovarian-tumor-domain-containing proteases (OTUs), a deubiquitinating enzymes family (DUBs), which is a cysteine proteasome-associated DUB to be involved in the Ub-dependent degradation of proteins. Therefore the expression of OTUB1 in colon cancer was examined and compared with precancerous lesion and normal colonic mucosa. Material/Methods: Tissue samples were obtained from 60 patients, and we took a piece of tissue from three different parts of the same patient, colon cancer, precancerous lesion and normal mucosa, respectively. Immunohistochemistry were carried out in colon cancer, precancerous lesion and normal mucosa. Results: Precancerous lesions and colon cancer tissues showed strong expression of OTUB1 in the cell cytoplasm. The expression of OTUB1 protein in the colon cancer was significantly higher than precancerous lesion and normal mucosa (PRead Complete Article at ijSciences: V5201601906 AND DOI: http://dx.doi.org/10.18483/ijSci.906

CdO nanoparticles with different sizes were synthesized by a simple thermal decomposition reaction of precursor obtained by room-temperature solid-state grinding reaction between Cd(CH3COO)22H2O and NaOH in the presence of PEG400. Composition, structure and morphology of the products were analyzed and characterized by X-ray diffraction technology, Transmission electron microscopy and Fourier infrared spectra. The formation of CdO nanoparticles is thought that the nucleation rate of the reactive system is far excess the growth rate of particle. Optical properties of the products were recorded, and the results show that Ultraviolet-visible (UV-vis) spectra exhibit distinct blue shift in comparison with them of the bulk CdO, which is because that the quantum confinement effect of the products is larger than the Coulomb effect. Photoluminescence (PL) spectra exhibit green and red emission bands around 520 and 720 nm respectively.

To evaluate the status of drug resistance among treat-naive HIV-1 infected men who have sex with men (MSM) in Shenzhen during the period of 2008 - 2010.Plasma samples of 227 treatment-naive HIV-1 infected MSM were collected in Shenzhen. HIV-1 pol genes (RT and PR) were amplified by nested-polymerase chain reaction (PCR) from RNA. Phylogenetic and drug resistance analyses were performed on the nucleotide sequence data.A total of 164 pol gene sequences were amplified. The prevalence of primary genotypic drug resistance was 14.6%. The overall prevalence of drug-resistant mutations was 22.6%, corresponding to 8.54% for protease inhibitors (PI) minor drug resistance mutation, 1.22% for nucleotide reverse transcriptase inhibitors (NRTI) drug resistance mutation and 13.41% for non-nucleotide reverse transcriptase inhibitors (NNRTI) drug resistance mutation. The prevalence of drug-resistant mutations was 30.88% for CRF01_AE strain and 19.23% for B strain.The prevalence of drug resistance is relatively moderate in the treat-naive HIV-1 infected MSM in Shenzhen. The prevalence of drug-resistant HIV-1 among MSM in Shenzhen should raise a high alert.

In China there has been an emerging epidemic of HIV and syphilis infections among men who have sex with men (MSM). Multiple surveys conducted in recent years have shown a high prevalence of syphilis infections among MSM in China. A rapid increase of HIV prevalence has been demonstrated among MSM in some areas including in China. For example the prevalence of HIV had increased from 0.4% in 2004 to 5.8% in 2006 in Beijing China. A high HIV prevalence has also been found among MSM in other Asian countries including Phnom Penn Cambodia (8.9%) Chiang Mai Thailand (15.3%) and Andhra Pradesh India (18.2%). In 2007 homosexual transmission has accounted for 12.2% of the 50000 estimated new HIV infections in China. Risk of HIV transmission is a particular concern in the context of current syphilis epidemic because infection with ulcerative STDs including syphilis has been shown to increase the risk of HIV transmission 3- to 5-fold. HIV may also increase the acquisition of other STDs and alter the natural history and response to standard therapy of ulcerative STDs resulting in an epidemiologic synergy between HIV and STDs. For these reasons there is particular concern about the potentially increasing transmission of HIV and syphilis among MSM. Because of overlaps in sexual networks between the MSM and non-MSM population it is also predicted that the transmission of HIV and syphilis among MSM may play an important role on driving the epidemic of HIV and syphilis in China in the future. This article presents results from 3 consecutive prevalence surveys of HIV and syphilis infections among MSM in Shenzhen of Guangdong China. This study aimed to understand the magnitude of HIV and syphilis infections among MSM trends in infection over time and the main corrects for infections in order to inform policy makers and develop an evidence-based syphilis control program. (excerpt)