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* Objective: To determine the risk for genital herpes and asymptomatic herpes simplex virus (HSV) shedding in late pregnancy and delivery in a population of HSV type 2 (HSV-2)-seropositive but previously asymptomatic pregnant women. * Design: A prospective inception cohort study. * Participants: A total of 1355 pregnant women with no history of genital herpes referred from three private obstetrics practices between November 1985 and June 1988. * Main Outcome Measures: Confidential questionnaires evaluated sexual risk factors in relation to HSV-2 serologic status as determined by Western blot analysis. Herpes simplex virus shedding was determined by viral culture of the cervix and vulva and of any suspicious lesions. * Results: Antibody to HSV-2 was detected in 439 of 1355 pregnant women (32%) with no history of genital herpes. Asymptomatic HSV shedding was detected in 5 of 1160 cultures (0.43%) obtained in late pregnancy and during delivery. A first episode of clinical genital herpes was recognized by 43 of 264 HSV-2-seropositive women (16%) during their pregnancy. * Conclusions: Serologic evidence of unknown HSV-2 infection was common in pregnant women without a history of genital herpes. Asymptomatic viral shedding in these women occurred at a rate similar to that seen in women with symptomatic genital HSV-2 infection. To improve recognition of genital herpes near term, obstetricians should counsel pregnant women about the high prevalence and mild and diverse symptoms of genital HSV-2 infection., Reactivation of herpes simplex virus type 2 (HSV-2) may occur in pregnant women with no history of genital herpes. Seventy-eight to 97% of individuals infected with HSV-2 have no symptoms. Among 1,355 pregnant women with no history of HSV-2 infection, 439 (32%) had developed antibodies to HSV-2. Of 264 women infected HSV-2 who were followed until delivery, 43 (16%) developed their first episode of genital herpes during their pregnancy. Approximately half of these women developed their first episode of genital herpes during the third trimester of pregnancy. Less than one percent of 1,160 cervical cultures obtained from women infected with HSV-2 revealed asymptomatic viral shedding during late pregnancy or at the time of delivery. Newborns exposed to HSV-2 during passage through the birth canal have a 3% to 8% risk of developing an HSV-2 infection.

Purpose: Rotating components such as rotating beams and plates are working in complex physical environments subjected to nonuniform distribution of their own materials, vibration caused by external excitation may result in work instability, structural fatigue and the like, so the dynamic analysis of rotating structures is of great significance. Methods: Based on the nonlocal elasticity theory and Timoshenko beam model, the vibration of a rotating functionally graded piezoelectric nanobeam is investigated. First, the dynamic governing equations and corresponding boundary conditions are derived by the Hamiltonian principle. Then, the governing equations and boundary conditions are discretized by the differential quadrature method. Subsequently, the vibration characteristics of nanobeams are analyzed after detailed numerical calculations. Results: The effects of various parameters including rotational velocity, nonlocal parameter, functional gradient index, length–height geometry ratio and external voltage on the vibration characteristics under different boundary conditions are examined. Finally, the numerical results show that these parameters have non-negligible effects on the natural frequencies and modal shapes. Conclusions: The dynamics of rotating functionally graded nanobeams are affected by both external kinematic and voltage factors and inherent scale factor and their coupling effects. In particular, a nonlinear small-scale effect is observed for a rotating functionally graded piezoelectric nanobeam, which may be useful to the design and optimization of the nano-electro-mechanical system including the rotating structures.

As several major new gas discoveries have been made recently in the Lower Cambrian Longwangmiao Fm reservoirs in the Leshan-Longnǚsi Palaeohigh of the Sichuan Basin, a super-huge gas reservoir group with multiple gas pay zones vertically and cluster reservoirs laterally is unfolding in the east segment of the palaeohigh. Study shows that the large-scale enrichment and accumulation of natural gas benefits from the good reservoir-forming conditions, including: (1) multiple sets of source rocks vertically, among which, the high-quality Lower Paleozoic source rocks are widespread, and have a hydrocarbon kitchen at the structural high of the Palaeohigh, providing favorable conditions for gas accumulation near the source; (2) three sets of good-quality reservoirs, namely, the porous-vuggy dolomite reservoirs of mound-shoal facies in the 2nd and 4th members of the Sinian Dengying Fm as well as the porous dolomite reservoirs of arene-shoal facies in the Lower Cambrian Longwangmiao Fm, are thick and wide in distribution; (3) structural, lithological and compound traps developed in the setting of large nose-like uplift provide favorable space for hydrocarbon accumulation. It is concluded that the inheritance development of the Palaeohigh and its favorable timing configuration with source rock evolution are critical factors for the extensive enrichment of gas in the Lower Cambrian Longwangmiao Fm reservoirs. The structural high of the Palaeohigh is the favorable area for gas accumulation. The inherited structural, stratigraphic and lithological traps are the favorable sites for gas enrichment. The areas where present structures and ancient structures overlap are the sweet-spots of gas accumulation.

This study investigates the effectiveness of the hole-drilling strain gage method on residual stress estimation. The thermal elastic-plastic model of the commercial Marc finite element method package is used to simulate and build up the hole-drilling process and residual stress distribution. Two Inconel 690 alloy plate welded with GTAW filler I-52 solder are first simulated using the Marc software. The traditional hole-drilling process is then simulated. The simulated residual strain variation data is incorporated into the hole-drilling strain-gage method to derive the possible residual stress components. The effects of drilling depth and drill size on the accuracy of residual stress estimates are also discussed. A comparison of stress components estimated from the traditional hole-drilling strain gage method and simulated from the Marc software is presented. The modified dimensionless parameters are provided by applying the optimum technique. The numerical results indicate that the proposed dimensionless parameters can significantly improve the accuracy of estimated residual stress components.

Abstract: A microcalorimetric technique was used to evaluate the influence of Er3+ on Halobacterium halobium R1 growth. By means of a LKB-2277 Bioactivity Monitor ampoule method, we obtained the thermogenic curves of H. halobium R1 growth at 37C. In order to analyze the results, the relationship between k and C was obtained. The addition of Er3+ in low concentration cause a decrease of the maximum heat production P max and growth rate constants k; however, Er3+ in a high concentration might promote growth of H. halobium R1. When Er3+ is in a much higher concentration, the growth of H. halobium R1 is inhibited completely. For comparison, the shapes of H. halobium R1 cells were observed by means of transmission electron microscope (TEM). According to the thermogenic curves and TEM photos of H. halobium R1 under different conditions, it is clear that the metabolic mechanism of H. halobium R1 growth has been changed with the addition of Er3+.

Abstract The 40Ar‐39Ar age method is employed in this work to analyze fluid inclusions of quartz in the ore bodies from the Kuo'erzhenkuola and Bu'erkesidai gold deposits in the Sawur gold belt, northern Xinjiang. The results show that the main mineralization occurred in 332.05±2.02–332.59±0.51 Ma and 335.53±0.32 Ma‐336.78±0.50 Ma for the Kuo'erzhenkuola and Bu'erkesidai gold deposits respectively, indicating that the two deposits are formed almost at the same time, and the metallogenic time of the two deposits are close to those of the hosting rocks formed by volcanic activity of the Sawur gold belt. This geochronological study supplies new evidence for determining the timing of gold mineralization, the geneses of gold deposits, and identifies that in the Hercynian period, the Altay area developed a tectonic‐magmatic‐hydrothermal mineralization of the Early Carboniferous period, except the two known mineralization periods including the tectonic‐magmatic‐hydrothermal mineralization of the Devonian period and Late Carboniferous‐Permian period.

Abstract: By using an LKB-2277 Bioactivity Monitor, cycle-flow method, the thermogenic curves of aerobic growth for Bacillus thuringiensis cry II strain at 28�C have been obtained. The metabolic thermogenic curves of B. thuringiensis cry II contained two distinct patterns: the first reflects the changes during the bacterial growth phase and the second corresponds to the sporulation phase. From these thermogenic curves in the absence and presence of Sm3+ ions, the thermokinetic parameters such as the growth rate constants k, the interval time τI, the maximum power P max 1 and heat-output Q log for log phase, the maximum power P max 2 and heat-output Q stat for stationary phase, the heat-output Q spor for sporulation phase and total heat effects Q T are calculated. Sm3+ ion has promoting action on the growth of B. thuringiensis cry II in its lower concentration range; on the other hand, this ion has inhibitory action on the sporulation of B. thuringiensis in its higher concentration range. We also found that the effects of Sm3+ ion on B. thuringiensis during the sporulation phase were far greater than that during the bacterial phase. It is concluded that the application of B. thruringiensis of controlling insecticides is not affected by the presence of the rare-earth elements in the environmental ecosystem.

Abstract: Rare earth elements have been emitted into the environment largely as fertilizer components. This has caused much fear about whether they would influence our environment, especially on the metabolism and genetics of microorganisms. In this article, the trivalent ion of a rare earth element, lanthanum, was studied for the effects on growth, transformation, and gene expression of Escherichia coli. The results showed that La3+ at concentrations from 50 to 150 �g/mL stimulated the endogenic metabolism and ectogenic metabolism, but had few effects on gene expression. La3+ at lower concentrations from 0.5 to 30 �g/mL inhibit intensively E. coli-absorbing external DNA, decreasing the transformation efficiency. It is also supported by observations using transmission electron microscopy. Our results are significant in understanding the function of rare earth elements to microorganisms and assessing the risk of application of rare earth compounds.

In this paper, a ?-N potential is presented. The long and medium range parts of this potential are given by the OBEP and TBEP , while the short range part by a phenomenological soft core. Based on the ?-N potential, the ?-separation energies and the spectra of and as well as the s-wave phase shifts and the cross section of the ?-N elastic scattering are calculated. The results are in good agreement: with the experimental data. Finally, the ?-well depth in nuclear matter is discussed.

We have calculated the cross section and the S wave phase shift of the ?-P elastic scattering by using the meson exchange potential which is obtained in Ref.[1]. The results are in good agreement with agreement with the experimental data.

The purpose of this paper is to study the ?-N interaction by using the meson exchange theory. We have considered four processes:l) Single K meson exchange, 2) Single ? and single ? meson exchange, 3) Box diagrams of 2? and ?? exchanges with the intermediate states of ?N, and 4) Box diagrams of 2? and ?? exchanges with the intermediate states of ??. For simplicity, the zero initial momentum approximation and the closure approximation have been taken in the calculation. The results are reasonable and consistent with experimental data. Especially for the cases of and , the theoretica1 spectra of and are in good agreement with experimental data.

Based on the first-hand information on the Zhongyuan-Huabei oil-gas area, this paper gives a description of the geochemical characteristics of the coal-type gas in this area. In terms of the carbon isotopic composition of methane, argon isotopic characteristics of natural gases, the carbon isotopic composition of condensate and the abundance of mercury in natural gases, the paper discusses the differences in chemical and isotopic compositions between the coal-type gas and the oil-type gas, and presents the indices for comprehensively distinguishing the coal-type gas from the oil-type gas. A systematic and scientific dissetation of some typical examples of gas reservoirs, such as the Wenliu, Suqiao and Shenze gas reservoirs, gives evidence suggesting that the gas reservoirs are of coal type. This indicates the existence of natural gas reservoirs of commercial value related to gas-source rocks of the Carboniferous-Permian coal series. This study provides important clues to the exploration and development of the coaltype gas reservoirs in China.

The relative importance of local and regional sources of lead and associated elements in fine and coarse aerosol particles of an urban atmosphere was assessed by means of a two-day study, July 20 and 30, 1980 in Beijing, China. Five near-ground locations were selected for aerosol sampling by cascade impactors and elemental analysis by proton induced X-ray emission (PIXE): the imperial palace courtyard, a park, near two streets, and a mid-street traffic island. These sites, ranked in order of increasing traffic intensity and fugitive surface dust, showed that concentrations of major dust constitutents, represented by coarse particle (>2 μm diameter) Si, Al, and Ca, increased correspondingly. Pb, as well as Zn, As, and Cu, were present mainly in fine (<2 μm) particles; their concentrations were unrelated to traffic, indicating they resulted mainly from regional combustion or other sources. However, these elements also were present in coarse particles at concentrations that varied with the major dust elements and were relatively enriched, compared to average earth crust rock material, by factors of more than 100 (Pb), 50 (Zn), and 10 (Cu). Nonurban Beijing shows much smaller coarse aerosol enrichments of Pb, Zn, and Cu, indicating urban contamination of surface dust. Published data from St. Louis, USA show both fine and coarse aerosol Pb and Zn. Compared with Beijing, fine and coarse concentrations in St. Louis are similar for Pb, but lower for Zn, Ca, and Fe. Both Pb and Zn are enriched relative to earth crust composition to a greater degree in St. Louis than Beijing in both fine and coarse particle size ranges. The results suggest that heavy metals from combustion occur in the air as fine particles and, after deposition on the surface, as reentrained coarse particles of fugitive dust. Both many contribute to human exposures of these heavy metals.

We study the Y(2175) using the method of QCD sum rules. There are two independent ssss interpolating currents with JPC=1--, and we calculate both their diagonal and their off-diagonal correlation functions. We obtain two new currents that do not strongly correlate to each other, so they may couple to two different physical states: one of them couples to the Y(2175), while the other may couple to another state whose mass is evaluated to be 2.41±0.25 GeV. Evidence of the latter state can be found in the BABAR [B. Aubert et al. (BABAR Collaboration), Phys. Rev. D 76, 012008 (2007)], BESII [M. Ablikim et al. (BES Collaboration), Phys. Rev. Lett. 100, 102003 (2008)], Belle [C. P. Shen et al. (Belle Collaboration), Phys. Rev. D 80, 031101 (2009)], and BESIII [M. Ablikim et al. (BESIII Collaboration), Phys. Rev. D 91, 052017 (2015)] experiments. [ABSTRACT FROM AUTHOR]

Reports on the expected increase in the net output of Indonesian Duri crude by December 1998. Volume of Duri crude pumped by equity producer Caltex; Transporting of gas from Asamera's Corridor Block in South Sumatra to replace Duri crude burned for steam generation; Expected startup for using gas for steam generation; Gas facilities planned by Asamera.

Discusses problems in a one-year experiment with exporting Alaskan crude. Impact of problems on British Petroleum (BP); American government's decision to lift the ban on Alaska North Slope (ANS) crude; Lack of success in BP's efforts to renew ANS term contracts.

Reports on Norway's indecision when to implement its crude oil production cuts. Norway's participation in a joint effort involving Organization of Petroleum Exporting Countries (OPEC) and non-OPEC producers to boost declining oil prices by reducing the world crude glut; Possibility of implementing cuts in April 1998.

The aim of this study was to investigate the expression of survivin and the apoptosis induced by DNR and BrTet in the leukemic cells K562/A02.In a typical experiment, the K562/AO2 cells were treated with daunorubicin (DNR), 5-bromotetrandrine (BrTet), or DNR and BrTet for 48 hours, and the cells treated without any drugs were used as control group. Cell proliferation was analyzed by MTT assay. Cells apoptosis and the concentration of DNR within the cells were measured by Flow cytometry (FCM). The expressions of mRNA and protein of survivin were determined by semi-quantitative reverse transcription PCR (RT-PCR) and Western blot, respectively.The results of MTT assay indicated that DNR and BrTet were both able to inhibit the proliferation of K562/AO2 cells in dose-dependent manner. The fresh evidence from flow cytometry showed that a higher apoptosis rate could be induced and a higer concentration of DNR could be detected in K562/AO2 cells by DNR and BrTet as compared with those by DNR or BrTet in the same concentrations(P<0.01). RT-PCR revealed that the expression of survivin mRNA, a higer expression in K562/AO2 cells with acquired resistance to adriamycin than that in parent K-562 cells, decreased in the DNR and BrTet group (P<0.05), but there was no obvious change in other groups(P>0.05). Western bolt demonstrated that the expression of survivin protein was much lower in the DNR and BrTet group(P<0.05).BrTet could increase the concentration of DNR and reverse the multidrug resistance(MDR) in the K562/AO2 cells. Survivin may play an important role in apoptosis induced by DNR. Survivin could be a target for the treatment of MDR in haematopoietic malignancies.No relevant conflicts of interest to declare.

No relevant conflicts of interest to declare.

Reports on the effects of weak petroleum demand to Asia. Causes of Asia's supply problems; Reason for Mobil Oil Singapore's reduction of its crude throughput at its Jurong refinery.

Reports on the condition of the petroleum industry in Japan. Factors that are influencing the condition of the industry; Petroleum companies that are operating at a loss; Ratings given on domestic bonds issued by some companies; Reason for the negative condition of the industry.

Reports on Atlantic Richfield's sale of the first parcel of its Qatari heavy crude Al-Rayyan. Selling price offered to Japan; Scheduled production at Al-Rayyan; Atlantic Richfield's plans for more oil field developments in Qatar.