Multipolar Planetary Nebulae: Not as Geometrically Diversified as Thought

Planetary nebulae (PNe) have diverse morphological shapes, including point-symmetric and multipolar structures. Many PNe also have complicated internal structures such as torus, lobes, knots, and ansae. A complete accounting of all the morphological structures through physical models is difficult. A first step toward such an understanding is to derive the true three-dimensional structure of the nebulae. In this paper, we show that a multipolar nebula with three pairs of lobes can explain many of such features, if orientation and sensitivity effects are taken into account. Using only six parameters - the inclination and position angles of each pair - we are able to simulate the observed images of 20 PNe with complex structures. We suggest that the multipolar structure is an intrinsic structure of PNe and the statistics of multipolar PNe has been severely underestimated in the past.Comment: 36 pages, 5 figures, 2 table

Characterization of Induced Seismicity in a Petroleum Reservoir: A Case Study

Fluid production and injection in hydrocarbon and geothermal reservoirs generally results in induced seismic activity. In this paper we study the microseismic activity in a petroleum field in Oman. The microearthquake data we used are those collected by a five-station digital network in the field between 29 October 1999 and 18 June 2001. We relocated 405 high-quality microseismic events using P and S travel-times picked from waveform data by the global grid-search location method. The results reveal a complex seismic zone with a NE-SW trend. All events are located within a depth range of 0.5 to 3.5 km. Focal mechanisms of 10 events of magnitude greater than one are inverted using the wavelet-based waveform inversion method where the source parameters, data kernel, waveform data, and the inversion are all represented by wavelet expansions. The dominant style of focal mechanism is left-lateral strike-slip for events with focal depths less than 1.5 km, and dip-slip along an obliquely trending fault for those with focal depths greater than 2.0 km. The inferred focal plane is nearly vertical and has a strike of NE-SW, which is also consistent with the trend of seismicity. To determine the cause of the events, seismicity rate is correlated with gas production and fluid injection. The results show that event rate in the field is strongly correlated with gas production in the Natih formation.Massachusetts Institute of Technology. Earth Resources LaboratoryPetroleum Development Oma

The Use of Medicinal Mushroom or Herb as Effective Immunomodulatory Agent

Background: Medicinal mushrooms are mushrooms used with the aim for health enhancement. They have been used in traditional Chinese medicine (TCM) for thousands of years. These mushrooms and some herbal medicines have gain in popularity in recent times, largely due to a growing number of scientific studies that suggest their potential medical benefits. They are found to exert immunomodulatory effects through changes in the quantity of some specific cytokines in blood; as well as numbers and activities of distinct immune cell subsets. This article summarizes the immunomodulatory effects of two commonly consumed medicinal mushrooms (Coriolus versicolor and Ganoderma lucidum) and also three herbal medicines that have been categorized as immunomodulatory in function (Cordyceps sinensis, Astragalus membranaceus and Eleutherococcus senticosus). Methods: A systematic search of published articles of clinical trial studies between 1985 and August 2015 was conducted in four electronic databases (EMBASE, PubMed, Scopus and Web of Science). The outcome measures included changes in the serum cytokines secretion and the number and functional activity of different immune cell populations. Results: After a thorough literature searching of 237 relevant articles, 15 were included. Coriolus versicolor and Ganoderma lucidum showed immunomodulatory effects in both innate and adaptive immunity arms. There are only very few studies in each mushroom or herb, and unequivocal conclusions cannot be drawn. Future larger trials of randomized and placebo controlled clinical studies with laboratory investigation of changes of multiple immune populations and their subsets are needed in consistent with an evidence-based medicine approach

Under-Pricing and Long-Run Performance of Initial Public Offerings in Developing Markets

The purpose of this paper is to examine the long-run performance of IPOs in developing markets using various methods to ascertain the significance of the over or under-performance of IPOs. Among the many reasons for the performance which we see, one of them could be the sensitivity of the results to the choice of benchmarks. Dimson and Marsh, Ritter, Gregory et al., Fama and French and Fama have successively demonstrated the sensitivity of the long-run performance of the IPOs the benchmark used in the study. For this reason, I am also motivated to study the effect of various benchmarks on the return measurements so as to elucidate the possibility that the magnitude of the performance is benchmark dependent. Finally, the focus of this study will be the Chinese and Indian markets

Investigation of the Biosynthetic Potential of Endophytes in Traditional Chinese Anticancer Herbs

Traditional Chinese medicine encompasses a rich empirical knowledge of the use of plants for the treatment of disease. In addition, the microorganisms associated with medicinal plants are also of interest as the producers of the compounds responsible for the observed plant bioactivity. The present study has pioneered the use of genetic screening to assess the potential of endophytes to synthesize bioactive compounds, as indicated by the presence of non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) genes. The total DNA extracts of 30 traditional Chinese herbs, were screened for functional genes involved in the biosynthesis of bioactive compounds. The four PCR screens were successful in targeting four bacterial PKS, six bacterial NRPS, ten fungal PKS and three fungal NRPS gene fragments. Analysis of the detected endophyte gene fragments afforded consideration of the possible bioactivity of the natural products produced by endophytes in medicinal herbs. This investigation describes a rapid method for the initial screening of medicinal herbs and has highlighted a subset of those plants that host endophytes with biosynthetic potential. These selected plants can be the focus of more comprehensive endophyte isolation and natural product studies

Laws Restricting Access to Abortion Services and Infant Mortality Risk in the United States

Objectives: Since the US Supreme Court′s 1973 Roe v. Wade decision legalizing abortion, states have enacted laws restricting access to abortion services. Previous studies suggest that restricting access to abortion is a risk factor for adverse maternal and infant health. The objective of this investigation is to study the relationship between the type and the number of state-level restrictive abortion laws and infant mortality risk. Methods: We used data on 11,972,629 infants and mothers from the US Cohort Linked Birth/Infant Death Data Files 2008–2010. State-level abortion laws included Medicaid funding restrictions, mandatory parental involvement, mandatory counseling, mandatory waiting period, and two-visit laws. Multilevel logistic regression was used to determine whether the type or number of state-level restrictive abortion laws during the year of birth were associated with odds of infant mortality. Results: Compared to infants living in states with no restrictive laws, infants living in states with one or two restrictive laws (adjusted odds ratio (AOR) = 1.08; 95% confidence interval [CI] = 0.99–1.18) and those living in states with 3 to 5 restrictive laws (AOR = 1.10; 95% CI = 1.01–1.20) were more likely to die. Separate analyses examining the relationship between parental involvement laws and infant mortality risk, stratified by maternal age, indicated that significant associations were observed among mothers aged ≤19 years (AOR = 1.09, 95% CI = 1.00–1.19), and 20 to 25 years (AOR = 1.10, 95% CI = 1.03–1.17). No significant association was observed among infants born to older mothers. Conclusion: Restricting access to abortion services may increase the risk for infant mortality

Structural racism and odds for infant mortality among infants born in the United States 2010

Abstract OBJECTIVES: While ecological studies indicate that high levels of structural racism within US states are associated with elevated infant mortality rates, studies using individual-level data are needed. To determine whether indicators of structural racism are associated with the individual odds for infant mortality among white and black infants in the US. METHODS: We used data on 2,163,096 white and 590,081 black infants from the 2010 US Cohort Linked Birth/Infant Death Data Files. Structural racism indicators were ratios of relative proportions of blacks to whites for these domains: electoral (registered to vote and voted; state legislature representation), employment (civilian labor force; employed; in management; with a bachelor\u27s degree), and justice system (sentenced to death; incarcerated). Multilevel logistic regression was used to determine whether structural racism indicators were risk factors of infant mortality. RESULTS: Compared to the lowest tertile ratio of relative proportions of blacks to whites with a bachelor\u27s degree or higher-indicative of low structural racism-black infants, but not whites, in states with moderate (OR = 1.12, 95% CI = 0.94, 1.32) and high tertiles (OR = 1.25, 95% CI = 1.03, 1.51) had higher odds of infant mortality. CONCLUSIONS: Educational and judicial indicators of structural racism were associated with infant mortality among blacks. Decreasing structural racism could prevent black infant deaths

Complicated acute type B aortic dissection: Midterm results of emergency endovascular stent–grafting

ObjectiveThis study assessed midterm results of emergency endovascular stent–grafting for patients with life-threatening complications of acute type B aortic dissection.MethodsBetween November 1996 and June 2004, 16 patients with complicated acute type B aortic dissections (mean age 57 years, range 16–88 years) underwent endovascular stent–grafting within 48 hours of presentation. Complications included contained rupture, hemothorax, refractory chest pain, and severe visceral or lower limb ischemia. Stent–graft types included custom-made first-generation endografts and second-generation commercial stent–grafts (Gore Excluder or TAG; W. L. Gore & Associates, Inc, Flagstaff, Ariz.). Follow-up was 100% complete, averaged 36 ± 36 months, and included postprocedural surveillance computed tomographic scans.ResultsEarly mortality was 25% ± 11% (70% confidence limit), with no late deaths. No new neurologic complications occurred. According to the latest scan, 4 patients (25%) had complete thrombosis of the false lumen; the lumen was partially thrombosed in 6 patients (38%). Distal aortic diameter was increased in only 1 patient. Actuarial survival at 1 and 5 years was 73% ± 11%; freedom from treatment failure (including aortic rupture, device fault, reintervention, aortic death, or sudden, unexplained late death) was 67% ± 14% at 5 years.ConclusionWith follow-up to 9 years, endovascular stent–grafting for patients with complicated acute type B aortic dissection conferred benefit. Consideration of emergency stent–grafting may improve the dismal outlook for these patients; future refinements in stent–graft design and technology and earlier diagnosis and intervention should be associated with improved results