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In this paper, an versatile and potential surface remelting strengthening technology, high-efficiency intelligent cladding (HEI-cladding) is presented. Ni-based alloy coatings were prepared by HEI-cladding. The microstructures of the cladding coatings were investigated by scanning electron microscopy, and the compositions were analyzed by electron diffraction spectroscopy. The phases of the cladding coating were clarified by X-ray diffraction technology. The microhardness of the coating was tested by microhardness tester. It shows that cladding coatings at 1298 K are denser and have fewer defects, while the number of the hard phases such as bulk structure, carbide and borideis are obviously increased. It shows that the grain size is much smaller than the overmelting temperature, the interfacial defects decreased significantly. The diffusion transfer band (DTB) width is 10–15 um at the interface of the coating prepared at 1298 K, which results in a good metallurgical reaction at the interface. The microhardness results show that the cladding coating at 1298 K has a smaller grain size, higher hardness in DTB near the interface and better microhardness distribution.

Alzheimer's disease (AD) and vascular dementia (VD) are serious, irreversible forms of cognitive impairment, which means that an early diagnosis is essential to slow down their progression. One potential neurophysiological biomarker of these diseases is the mismatch negativity (MMN) event-related potentials (ERP) component, which reflects an automatic detection mechanism at the pre-attentive stages of information processing. We evaluated the auditory MMN response in individuals from two patient groups: those in the prodromal stages of AD (P-AD) and those in the prodromal stages of VD (P-VD). Thirty patients (15 P-AD patients and 15 P-VD patients) and 30 age-matched controls were recruited to undergo electrophysiological recordings during the presentation of an auditory deviant-standard-reverse oddball paradigm that was used to elicit genuine MMN responses. We show that over the frontal-central area, the mean amplitude of the MMN was significantly reduced in both the P-AD (p=0.017) and P-VD groups (p=0.013) compared with controls. The MMN peak latency in P-VD patients was significantly shorter than in controls (p=0.027). No MMN response differences between the P-AD and P-VD were found in either the frontal-central or the temporal areas. These results indicate that P-AD and P-VD patients exhibit impaired pre-attentive information processing mechanisms as revealed by the frontal-central area MMN response, which is associated with sensory memory and cognitive deficits.

In this numerical study, it was mainly intended to investigate the flow and flow control for a practical drilling riser system with auxiliary lines at various incidence angles. The flow past the riser system was simulated through solving the Reynolds averaged Navier–Stokes equations and k−ω turbulence model. The cases about fluid flow past single cylinder, two staggered cylinders and eight even-distributed auxiliary lines around main line were simulated first, and the results match well with previous researches. The Reynolds number (Re) used here was 35,000, which belongs to the subcritical Reynolds region, and the flow in this Reynolds region can shows the typical flow characteristics in practical drilling operator. The effects of the incidence angle, which was in the range of 0–360° and at 30° intervals, on the drag and lift coefficients, the pressure distribution around the main line, the vortex shedding frequencies and the flow structure were investigated. The mean and RMS values of the drag and lift coefficients of the main line vary with the incidence angle irregularly due to the complexity of the geometry of the riser system. The flow patterns can be classified into six types based on the time-averaged streamlines. The effects of the auxiliary lines on mean force coefficients of the main line in different flow patterns were discussed in detail based on the distributions of the pressure on the main line. The auxiliary lines can suppress the vortex shedding on the main line at all incidence angles. Especially, in the CVP (clamped vortices pair, α=210° and α=330°) pattern, the vortex shedding behind the main line is suppressed most effectively by multiple downstream auxiliary lines. The mean value of the drag coefficient is just about 45.5% of that of the single cylinder, and the RMS value of the lift coefficient is about 1.5% of that of the single cylinder. This is the favorable condition for drilling operation. The worst effect of suppression occurs in the SLA (shear layers afflux, α=90°) pattern, and the RMS value of the lift coefficient is about 76.8% of that of the single cylinder. Due to the interaction between the vortices shed from different lines in riser system, the frequencies of the lift coefficients of the lines in riser system change largely, and some higher frequencies appear in the lift coefficients of the main line. As α=60° and α=120°, the Strouhal number of the main line is about 0.75.

To meet the requirements of riser safety monitoring in offshore oil fields, a new Fiber Bragg Grating (FBG)-based bundle-structure riser stress monitoring sensor has been developed. In cooperation with many departments, a 49-day marine test in water depths of 1365 m and 1252 m was completed on the “HYSY-981” ocean oil drilling platform. No welding and pasting were used when the sensor was installed on risers. Therefore, the installation is convenient, reliable and harmless to risers. The continuous, reasonable, time-consistent data obtained indicates that the sensor worked normally under water. In all detailed working conditions, the test results show that the sensor can do well in reflecting stresses and bending moments both in and in magnitude. The measured maximum stress is 132.7 MPa, which is below the allowable stress. In drilling and testing conditions, the average riser stress was 86.6 MPa, which is within the range of the China National Offshore Oil Corporation (CNOOC) mechanical simulation results.

Firstly, aiming at the characteristics of accuracy and complexity of uncertain information representation. the interval grey number extended the general grey number. Then, the concept of extended general grey number is put forward based on grey number theory, which is used to represent complex uncertain information. Secondly, according to the essence of the kernel and degree of greyness of general grey number, the basic method of reducing general grey number to interval grey number is given. Thirdly, the measurement method of general grey number distance is given based on the essential characteristics of kernel and grey degree and Euclidean metric. Finally, from perspective of expectation and variance, the concept of kernel expectation and kernel variance of general grey number is put forward, and the ranking method of general grey number is given.

In deep-water drilling processes, the flow rate of drilling mud inside an annular pipe is significant judgment data for early kick detection. On the basis of the continuous-wave Doppler ultrasound, this paper proposes a new detection method of nonoriented continuous-wave Doppler ultrasound. The method solves the problem of the ultrasound having great attenuation in mud and not receiving effective signals by using a continuous ultrasound. Moreover, this method analyzes the nonoriented characteristics of ultrasound reflection on principle and proposes the detection of ultrasound Doppler frequency shift by detecting Lamb wave, which releases the detection of oil-based mud flow rate in a nonintrusive annular pipe. The feasibility of the method is verified through theoretical analysis and numerous experiments on a gas kick simulation platform. The measurement result has reached a flow accuracy approximating to the intrusive flow meter.

A kind of bare fiber Bragg grating (FBG) gas pressure sensor based on fiber loop ring-down is presented, in which there are no sensitizing means or assistant structure on the bare FBG. The pressure sensitivity is analyzed theoretically via discussing the relationship between the ring-down time and the gas pressure. By detecting the ring-down time at different gas pressure levels, the gas pressure characteristics of the bare FBG are investigated in the time domain. The experimental results demonstrate that there exists a linear dependence of the pressure applied to the bare FBG on the ring-down time. A high sensitivity of −0.384 μs/MPa (being equivalent to −240 pm/MPa) could be achieved, which is 79 times larger than that of the optical spectral analyzer interrogated. This kind of pressure sensor could be used for gas or liquid pressure measurement.

Scutellaria baicalensis is a widely used Chinese herbal medicine historically used in antiinflammatory and anticancer therapy. The goals of the study were to 1) determine its in vitro and in vivo anti-prostate cancer activity, 2) investigate its molecular mechanism directed at cell proliferation control including cyclooxygenase-2(COX-2) prostaglandin E2 (PGE2) and cyclins/cdks pathways, and 3) compare it with those of PC-SPES (PC stands for prostate cancer and spes is Latin for hope), a former herbal mixture for prostate cancer treatment of which S. baicalensis is a major constituent. Two human prostate cancer cell lines (LNCaP, androgen dependent, and PC-3, androgen independent) were assessed for growth inhibition. S. baicalensis exerted dose- and time-dependent increased growth inhibition in both cell lines. However, the PC-3 cells IC50 (50% growth inhibition concentration) were slightly more sensitive than LNCaP cells (IC50=0.15 mg/ml), although the former is androgen independent. S. baicalensis was more effective in inhibition of cell growth compared with PC-SPES (IC50=0.38 mg/ml for PC-3 cells). Significant reduction of PGE2 synthesis in both cells after treatment with S. baicalensis resulted from direct inhibition of COX-2 activity rather than COX-2 protein suppression. S. baicalensis also inhibited prostate-specific antigen production in LNCaP cells. Finally, S. baicalensis suppressed expression of cyclin D1 in LNCaP cells, resulting in a G1 phase arrest, while inhibiting cdk1 expression and kinase activity in PC-3 cells, ultimately leading to a G2/M cell cycle arrest. Animal studies showed a 50% reduction in tumor volume after a 7-wk treatment period. This study demonstrated that S. baicalensis may be a novel anticancer agent for the treatment of prostate cancer.

Epstein-Barr virus (EBV), one of the most common human viruses, is a member of the Herpesviridae family. EBV infects more than 90% of the world's population and remains latent in B-cell lymphocytes. EBV is associated with the development of certain malignancies, including lymphoma and posttransplant

Abstract In the mid 2012, three deep water exploration wells have been accomplished in the South China Sea by CNOOC as the operator employing the deep water drilling unit HYSY981, which symbolizes the epoch of deep water drilling of CNOOC. By reviewing the history of deep water drilling implemented by CNOOC and its partners, this paper put forward the key challenges of deep water drilling in South China Sea, such as typhoon, soliton, gas hydrates and so on. Potential solutions to these challenges are discussed in the paper, aiming at drilling safety. Firstly, this paper focuses on the strategy of the typhoon resistance for the new building deep water drilling unit (DWDU) HYSY981. On which the preliminary research results are given in the paper. The typhoon resistance solution is drawn up in combination with the platform dynamic analysis and operational mode that have been performed to demonstrate its feasibility. Secondly, the paper shows solutions to the soliton for deep water drilling in the South China Sea. And finally, the recommendation to deal with the risk of hydrate formation in deep water drilling is summarized. 1 Introduction The construction of deep water semi-submersible drilling unit HYSY981, which was sponsored by CNOOC, begun from April 28th, 2008 and was finished on February 26th, 2010. The drilling unit HYSY981 is the first sixth generation semi-submersible drilling unit in China, which is designed and constructed independently by CNOOC. For HYSY981, the operating water depth beyond 3000m, the deck area is 114m length and 89m width. General 3rd dynamic position system is deployed on the drilling unit, while the unit itself can be positioned by anchoring when it is operated in waters less than 1500m deep. The drilling unit was designed to be able to maintain position in the occurrence of a-200years-return typhoon condition.[1] The drilling unit HYSY981 carried out the first well drilling operation on March 6th, 2012 at the LH29–2–1 location. And until August 8th, 2012, the drilling unit has finished drilling and completion operation of three wells, which are LH29–2–1(754m water depth), LW6–1–1(1495m WD), and BY13–2–1(688m WD). During the process of drilling operations at these well locations, HYSY981 experienced four typhoons and twelve solitons. While taking reasonable measures to deal with these threats, the operator CNOOC has summarized experience of dealing with various deep water drilling problems, which forms recommendation for consequential deep water drilling operation of HYSY981 drilling unit in South China Sea. From 2006 on, CNOOC and its partners such as Husky and Devon, has finished drilling and completion operations of 32 wells, including LW3–1–1, BY6–1–1, LW3–1–2, LH29–1–1, LH34–2–1 and LW3–1–10. During these operations period, there are 56 accidents, 20 of which cost NPT more than 100hrs. Figure.1 shows that weather influence and BOP accident are two main factors influencing South China Sea deep water drilling. Severe weather conditions seriously affect drilling operations. When Husky carried out drilling operation at LH34–2–1 location, typhoon " Koppu" attacked the drilling unit HYSY981, with the drilling riser & LMRP hanged on rotary table, the drilling unit was push to shallow water district, the LMRP collided with seafloor, which resulted in the damage of riser joint, telescopic joint and tensioner. More than 50 regular work days and 50 million dollars were lost. [2] By reviewing the history of deep water drilling implemented by CNOOC and its partners in the South China Sea, this paper presents the key challenges to deep water drilling, such as typhoon, soliton, gas hydrates and so on, which are unique in the South China Sea. Firstly, proposed strategy solutions of the typhoon resistance for HYSY981 to these challenges are discussed in the paper, and these solutions should be draw up in combination with the platform structural analysis and operational mode.

It is very important to monitor the lateral and axial strains of drilling riser for evaluation its health in deepwater. An optical fiber strain sensing system based on optical fiber Bragg gratings (FBGs) used for monitoring the strain of drilling riser is presented. The optical fiber strain sensors are made by embedding FBGs into thin columned fiber reinforced polymer which protect FBGs from seawater corrosion. Four optical fiber strain sensors are installed parallel to the riser axis and arranged at 90° angles around the riser by a home-made metal belt, at the same time, twelve resistance strain gauges are pasted near the sensors around the drilling riser at 30° angles as reference sensors. A scaled drilling riser about 1 meter long and 0.245m diameter is pressed in the lateral and axial direction in the range of 0-400KN, the experimental results show that the relative error between optical fiber strain sensors and resistance strain gauges is less than 6%.

Marine riser fatigue damage in the hostile ocean environments is the fatal issue for deep and ultra deep waters petroleum and gas drilling and productions during. Strain detecting provides a direct measure of the riser fatigue. One riser fatigue monitoring formula based on FBG sensor with orthogonal distribution was researched which takes into account temperature compensation function. Mathematical model for calculating stress and bending moment of riser with the relative change in the Bragg wavelength was presented. One riser stress-strain measuring device based on FBG sensor was designed. Strain measurement tests of a riser scale model were performed. The study shows that the riser fatigue monitoring formula based on FBG sensor presented in this paper is reasonable, and the research results provide the technical support for field practice.

The systemic pharmacological treatment of disease is limited by severe toxicity to normal organs/tissue. Therefore, various delivery vehicles have been designed to carry therapeutic drugs to their target tissues. We designed a novel vehicle formed by the interaction of biotins in a DNA (polymer) with avidins (crosslink), resulting in a porous particle. This self-assembled (HSAM) nanoparticle vehicle has been tested in our laboratory both in vitro and in vivo for its ability to carry doxorubicin, a widely used anticancer drug with a high toxicity to normal organs. Doxorubicin binds to the nanoparticle by intercalating into the DNA strands that are later degraded by nucleases released from cancer cells. Our results showed that 1.1 microg of HSAM DNA can carry 1 microg of doxorubicin, and the doxorubicin-bound HSAM nanoparticle can still be degraded by nucleases (BAL-31 and DNase I). The HSAM nanoparticle carrying doxorubicin can efficiently inhibit cancer cell growth in vitro and in a murine model. Furthermore, this nanoparticle is able to deliver up to 180 ng/mg of doxorubicin to the target tumor tissue, which is 15-fold above the systemic toxicity dose (12 mg/kg). These results suggest that the HSAM nanoparticle is both biocompatible and biodegradable, making it a valuable vehicle for drug delivery in cancer treatment.

Botanical products have been widely used for various illnesses and general well-being. However, quality control of botanical products is often not performed due to lack of standardization, resulting in inconsistent efficacies and sometimes serious toxicity. The goals of this study were to determine the correlation between chemical composition and biological activities and to establish a method to measure authenticity, chemical consistency, and biological potency of botanical products. A high-performance liquid chromatography method was used to analyze the authenticity and chemical composition of 10 different commercial extracts. The cell viability assay and prostaglandin E2 (PGE2) enzyme immunoassay were used to analyze biological potency and consistency. Our results showed all extracts contained marker components (baicalein and/or baicalin), confirming their authenticity. However, significant product-to-product and batch-to-batch variation of these marker components was observed with 4 products containing no baicalin at all and baicalein concentration ranging from 0 to 52.3 g/mg. The 50% growth inhibition concentration of the extracts ranged from 0.18 to 2.0 mg/ml, more than an 11-fold variation. PGE2 levels varied from 19.5 to 111.1 pg/106 cells, more than a 5.7-fold difference. These results demonstrated significant variation in chemical composition and biological activities of the commercial extracts and that the amount of marker components may not reflect biological activity levels. Therefore, chemical analysis alone is inadequate for quality control, and biological assays must be included for botanical products to ensure chemical authenticity as well as pharmacological/biological potency and consistency.

Scutellaria baicalensis is a widely used Chinese herbal medicine that has been used historically in anti-inflammatory and anticancer therapy. The purpose of this study is to verify its anticancer activity on head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo and to investigate its effect on cyclooxygenase-2 (COX-2), which converts arachidonic acid to prostaglandin E(2) (PGE(2)) and is highly expressed in HNSCC. Two human HNSCC cell lines (SCC-25 and KB) and a nontumorigenic cell line (HaCaT) were tested in vitro for growth inhibition, proliferation cell nuclear antigen expression, and COX-2 activity and expression after treatment with Scutellaria baicalensis extract. Its effects were compared with those of baicalein (a flavonoid isolated from Scutellaria baicalensis), indomethacin (a nonselective COX inhibitor), and celecoxib (a selective COX-2 inhibitor). Four nude mice with s.c. inoculation of KB cells were tested for its anticancer activity in vivo by oral administration of Scutellaria baicalensis at a dose of 1.5 mg/mouse (75 mg/kg), five times/week for 7 weeks. Scutellaria baicalensis and other agents demonstrated a strong growth inhibition in both tested human HNSCC cell lines. No growth inhibition of HaCaT cells was observed with Scutellaria baicalensis. The IC(50)s were 150 micro g/ml for Scutellaria baicalensis, 25 micro M for celecoxib, and 75 micro M for baicalein and indomethacin. Scutellaria baicalensis, as well as celecoxib and indomethacin, but not baicalein, suppressed proliferation cell nuclear antigen expression and PGE(2) synthesis in both cell types. Scutellaria baicalensis inhibited COX-2 expression, whereas celecoxib inhibited COX-2 activity directly. A 66% reduction in tumor mass was observed in the nude mice. Scutellaria baicalensis selectively and effectively inhibits cancer cell growth in vitro and in vivo and can be an effective chemotherapeutic agent for HNSCC. Inhibition of PGE(2) synthesis via suppression of COX-2 expression may be responsible for its anticancer activity. Differences in biological effects of Scutellaria baicalensis compared with baicalein suggest the synergistic effects among components in Scutellaria baicalensis.