Sensitivity studies for r-process nucleosynthesis in three astrophysical scenarios

In rapid neutron capture, or r-process, nucleosynthesis, heavy elements are built up via a sequence of neutron captures and beta decays that involves thousands of nuclei far from stability. Though we understand the basics of how the r-process proceeds, its astrophysical site is still not conclusively known. The nuclear network simulations we use to test potential astrophysical scenarios require nuclear physics data (masses, beta decay lifetimes, neutron capture rates, fission probabilities) for all of the nuclei on the neutron-rich side of the nuclear chart, from the valley of stability to the neutron drip line. Here we discuss recent sensitivity studies that aim to determine which individual pieces of nuclear data are the most crucial for r-process calculations. We consider three types of astrophysical scenarios: a traditional hot r-process, a cold r-process in which the temperature and density drop rapidly, and a neutron star merger trajectory.Comment: 8 pages, 4 figures, submitted to the Proceedings of the International Nuclear Physics Conference (INPC) 201

Faster subsequence recognition in compressed strings

Computation on compressed strings is one of the key approaches to processing massive data sets. We consider local subsequence recognition problems on strings compressed by straight-line programs (SLP), which is closely related to Lempel--Ziv compression. For an SLP-compressed text of length $\bar m$, and an uncompressed pattern of length $n$, C{\'e}gielski et al. gave an algorithm for local subsequence recognition running in time $O(\bar mn^2 \log n)$. We improve the running time to $O(\bar mn^{1.5})$. Our algorithm can also be used to compute the longest common subsequence between a compressed text and an uncompressed pattern in time $O(\bar mn^{1.5})$; the same problem with a compressed pattern is known to be NP-hard

Advances in nickel hydrogen technology at Yardney Battery Division

The current major activites in nickel hydrogen technology being addressed at Yardney Battery Division are outlined. Five basic topics are covered: an update on life cycle testing of ManTech 50 AH NiH2 cells in the LEO regime; an overview of the Air Force/industry briefing; nickel electrode process upgrading; 4.5 inch cell development; and bipolar NiH2 battery development

Electromagnetic Dipole Strength in Transitional Nuclei

Electromagnetic dipole absorption cross-sections of transitional nuclei with large-amplitude shape fluctuations are calculated in a microscopic way by introducing the concept of Instantaneous Shape Sampling. The concept bases on the slow shape dynamics as compared to the fast dipole vibrations. The elctromagnetic dipole strength is calculated by means of RPA for the instantaneous shapes, the probability of which is obtained by means of IBA. Very good agreement with the experimental absorption cross sections near the nucleon emission threshold is obtained.Comment: 4 pages, 4 figure

Hormonal regulation of female reproduction

Reproduction is an event that requires the coordination of peripheral organs with the nervous system to ensure that the internal and external environments are optimal for successful procreation of the species. This is accomplished by the hypothalamic-pituitary-gonadal axis that coordinates reproductive behavior with ovulation. The primary signal from the central nervous system is gonadotropin-releasing hormone (GnRH), which modulates the activity of anterior pituitary gonadotropes regulating follicle stimulating hormone (FSH) and luteinizing hormone (LH) release. As ovarian follicles develop they release estradiol, which negatively regulates further release of GnRH and FSH. As estradiol concentrations peak they trigger the surge release of GnRH, which leads to LH release inducing ovulation. Release of GnRH within the central nervous system helps modulate reproductive behaviors providing a node at which control of reproduction is regulated. To address these issues, this review focuses on several critical questions. How is the HPG axis regulated in species with different reproductive strategies? What internal and external conditions modulate the synthesis and release of GnRH? How does GnRH modulate reproductive behavior within the hypothalamus? How does disease shift the activity of the HPG axis.Fil: Christensen, A.. University of California at Los Angeles; Estados UnidosFil: Bentley, G. E.. University of California at Berkeley; Estados UnidosFil: Cabrera Kreiker, Ricardo Jorge. Universidad de Mendoza; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Ortega, Hugo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Litoral; ArgentinaFil: Perfito, N.. University of California at Berkeley; Estados UnidosFil: Wu, T. J.. Uniformed Services University Of The Health Sciences; Estados UnidosFil: Micevych, P.. University of California at Los Angeles; Estados Unido

Peripheral and central mechanisms involved in hormonal control of male and female reproduction

Reproduction involves the integration of hormonal signals acting across multiple systems togenerate a synchronized physiological output. A critical component of reproduction is the luteinizinghormone (LH) surge, which is mediated by estradiol (E2) and neuroprogesterone interacting tostimulate kisspeptin release in the rostral periventricular nucleus of the third ventricle in rats. Recentevidence has shown that both classical and membrane E2 and progesterone signaling is involved inthis pathway. A metabolite of gonadotropin-releasing hormone (GnRH), GnRH-(1-5), has been shownto stimulate GnRH expression, secretion, and has a role in the regulation of lordosis. Additionally,gonadotropin-inhibitory hormone (GnIH) projects to and influences the activity of GnRH neurons inbirds. Stress-induced changes in GnIH have been shown to alter breeding behaviors in birds,demonstrating another molecular control of reproduction. Peripherally, paracrine and autocrineactions within the gonad have been suggested as therapeutic targets for infertility in both males andfemales. Dysfunction of testicular prostaglandin synthesis is a possible cause of idiopathic maleinfertility. Indeed, local production of melatonin and corticotropin-releasing hormone (CRH) couldinfluence spermatogenesis via immune pathways in the gonad. In females, vascular endothelialgrowth factor A (VEGF-A) has been implicated in an angiogenic process that mediates developmentof the corpus luteum and thus fertility via the Notch signaling pathway. Age-induced decreases infertility involve ovarian kisspeptin and its regulation of ovarian sympathetic innervation. Finally,morphological changes in the arcuate nucleus of the hypothalamus influence female sexualreceptivity in rats. The processes mediating these morphological changes have been shown toinvolve rapid effects of E2 controlling synaptogenesis in this hypothalamic nucleus. Together, thisreview highlights new research in these areas, focusing on recent findings in the molecularmechanisms of central and peripheral hormonal control of reproduction.Fil: Rudolph, L. M.. University of California at Los Angeles; Estados UnidosFil: Bentley, G. E.. University of California Berkeley; Estados UnidosFil: Calandra, Ricardo Saul. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Paredes, A. H.. Universidad de Chile; ChileFil: Tesone, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Wu, T. J.. Uniformed Services University; Estados UnidosFil: Micevych, P. E.. University of California at Los Angeles; Estados Unido

Gladstone air study 2009-2010 : Monitoring for polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzo-p-dioxins (PCDDs) & furans (PCDFs) and polychlorinated biphenyls (PCBs).

EXECUTIVE SUMMARY The Gladstone Air Study was initiated as part of the Clean & Healthy Air for Gladstone (CHAG) project established by Queensland Health and the Department of Environment and Resource Management. This project arose in response to community concern regarding the perceived cumulative impact of industrial growth in the Gladstone region on air quality and the consequences for human health. The Gladstone Air Study, as a component of CHAG, aimed to provide data which will profile the levels and types of specific hazardous air pollutants (HAPs) and allow for an assessment of the subsequent health risks they pose to humans living and working in the Gladstone region. The specific HAPs, which were targeted in the Gladstone Air Study, included polycylic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs). These HAPs were monitored over a twelve month period between February 2009 and January 2010. Monitoring was conducted on a monthly basis at two sites (South Gladstone and Targinie) and in winter (June/July 2009) and summer (December 2009) at an additional four sites (Boyne Island, Clinton, Auckland Point, and Boat Creek) within the Gladstone Air Monitoring Network. Some additional monthly monitoring occurred at Boyne Island in October and November. Overall this monitoring for HAPs in the Gladstone region has found that the concentrations of PAHs, PCBs and PCDD/Fs in air: „h are within available health based guidelines (National Environmental Protection Measure (Air Toxics) monitoring investigation levels) established for benzo[a]pyrene as a marker for PAH exposure; „h do not contribute significantly to nor exceed available international exposure standards for intake of ¡§dioxin-like¡¨ PCBs and PCDD/Fs recommended by the National Health and Medical Research Council within Australia; and „h are consistent with, or lower than the concentrations measured in other parts of Australia. There was however considerable variation in the concentrations and profiles of specific HAPs within the Gladstone region. Overall the maximum concentrations of all PAH markers of exposure for the region occurred at the South Gladstone site and in summer. The maximum monthly and annual average concentrations of benzo[a]pyrene at this location were 0.14 ng.m-3 and 0.046 ¡Ó 0.045 ng.m-3 respectively, while the regional average concentration (all data) was 0.032 ¡Ó 0.034 ng.m-3. These average concentrations are approximately an order of magnitude lower than the annual average monitoring investigation level of 0.3 ng.m-3 established under the National Environmental Protection Measure (Air Toxics). The concentrations of benzo[a]pyrene in the Gladstone region are similarly lower than the concentrations measured previously in ambient air in major cities in Australia. The maximum monthly concentrations of PCDD/Fs and ¡§dioxin-like¡¨ PCBs expressed as World Health Organization toxic equivalent air concentrations (WHO05 TEQDF and WHO05 TEQP respectively) occurred at South Gladstone in summer (12 fg.m-3) and Boyne Island in winter (0.40 fg.m-3). South Gladstone also had the highest annual average WHO05 TEQDF (4.5 fg.m-3) in the region while Auckland Point had the highest average WHO05TEQP (0.34 fg.m-3). The regional average WHO05 TEQDF and WHO05 TEQP were 2.3 fg.m-3 and 0.14 fg.m-3 respectively. The regional average and range of 2.3 ¡Ó 2.4 (0.24 ¡V 12) fg.m-3 for WHO05 TEQDF measured in the Gladstone region are very consistent with the finding of the National Dioxin Program Page 2 conducted in 2003 which indicated that the concentrations in ambient air in Australia are very low by world standards. For example WHO98 TEQDF average (and range) concentrations of 8.9 (0.73 ¡V 41), 1.5 (0.27 ¡V 4.04), 1.1 (0.11 -121), 2.8 (0.29 ¡V 13) fg.m-3 were reported for Eagle Farm in Brisbane, Mutdapilly south west of Brisbane, Cape Grim in Tasmania and Berrimah in Darwin, respectively. The dominant PCDD congener across the Gladstone region was octachlorodibenzo-p-dioxin (OCDD) which is approximately 10 000 times less potent than the reference dioxin congener 2,3,7,8-tetrachnlorodibenzo-p-dioxin (2,3,7,8-TCDD). Average OCDD concentrations ranged from 30 ¡Ó 24 fg.m-3 at Boyne Island to 78 ¡Ó 57 fg.m-3 at South Gladstone. 2,3,7,8-TCDD was only detected at the South Gladstone site in concentrations ranging from 0.50 fg.m-3 to 2.9 fg.m-3. The highest concentrations of PCDF congeners occurred at Targinie and Boat Creek in the north of the region. These elevated PCDF profiles, where maximum concentrations were observed in winter, may reflect some preservation of wood smoke source profiles within the ambient profiles at these locations. The dominant non-ortho PCB congener in the Gladstone region was PCB 77. The average concentrations for this congener ranged from 10 fg.m-3 at Boat Creek and Targinie in the north of the region to 55 fg.m-3 at Auckland Point. The most potent ¡§dioxin-like¡¨ PCB monitored was the non-ortho congener PCB 126 which has an WHO05 TEF of 0.1 (10 times less potent than 2,3,7,8-TCDD). This congener was present at relatively low concentrations across the region with average concentrations ranging from 0.75 ¡V 2.8 fg.m-3 at Clinton and Auckland Point respectively. The most dominant mono-ortho ¡§dioxin-like¡¨ PCB was PCB 118 which was present at maximum values ranging from 517 fg.m-3 at South Gladstone to 1321 fg.m-3 at Auckland Point. It should be noted that this congener was not detected in any of the monitoring periods at sites to the north of Gladstone (Targinie and Boat Creek). While PCB 118 was detected at relatively high concentrations compared to many of the other ¡§dioxin-like¡¨ PCBs, all of the mono-ortho PCBs exhibit a relatively low potency with respect to 2,3,7,8-TCDD