SP-100 control drive assembly development

The SP-100 is an electrical generating nuclear power system for space operation. This paper describes the nuclear reactor control systems and the methods used to assure reliable performance for the 10-year design life. Reliable performance is achieved by redundancy and by selecting highly reliable components and design features. Reliability is quantified by analysis using established reliability data. Areas lacking reliability data are identified for development testing. A specific development test description is provided as an example to demonstrate how this process is meeting the system reliability goals

Land-use controls for outdoor recreation areas

Land-use planning and control is fast becoming a major issue in the United States. Dwindling natural resources, a growing population, a recognized need for a quality environment, and several incidents of controversial resource management have brought land-use problems to the public eye. State land-use legislation, numerous court cases, and extensive debate have resulted. Central to the general debate is concern over the role of government in this area, formerly considered to be the realm of the individual and private firm. This paper is designed to help clarify the role of government in land-use planning and control by analyzing the powers available to government entities in providing opportunities for outdoor recreation.https://lib.dr.iastate.edu/specialreports/1074/thumbnail.jp

Referral patterns of children with glaucoma and their caretakers in Northern Tanzania.

AIM: To describe the referral patterns of children with primary childhood glaucoma (PCG) or secondary childhood glaucoma (SCG) and their presenting symptoms in Northern Tanzania. METHODS: A retrospective observational study of children 0.48, better eye). Most of the children (60%) and their caretakers presented on their own initiative, while 24% were sent by different general health cadres and 16% by eye care professionals. Buphthalmos was the main symptom mentioned as a trigger for presentation. CONCLUSION: The study shows that most of the children presented late resulting in advanced stages of glaucoma at the time of initiation of treatment. The majority attended the referral eye department on their own initiative with buphthalmos being the most commonly described symptom. Awareness creation among caretakers of children, general health and eye care providers, ideally embedded in general child health promotion activities, is needed to increase and accelerate referrals

Two distinct halo populations in the solar neighborhood. IV. Lithium abundances

We investigate if there is a difference in the lithium abundances of stars belonging to two halo populations of F and G main-sequence stars previously found to differ in [alpha/Fe] for the metallicity range -1.4 < [Fe/H] < -0.7. Li abundances are derived from the LiI 6707.8 A line measured in high-resolution spectra using MARCS model atmospheres. Furthermore, masses of the stars are determined from the logTeff - logg diagram by interpolating between Yonsei-Yale evolutionary tracks. There is no significant systematic difference in the lithium abundances of high- and low-alpha halo stars. For the large majority of stars with masses 0.7 < M/M_sun < 0.9 and heavy-element mass fractions 0.001 < Z < 0.006, the Li abundance is well fitted by a relation A(Li) = a0 + a1 M + a2 Z + a3 M Z, where a0, a1, a2, and a3 are constants. Extrapolating this relation to Z = 0 leads to a Li abundance close to the primordial value predicted from standard Big Bang nucleosynthesis calculations and the WMAP baryon density. The relation, however, does not apply to stars with [Fe/H] < -1.5. We suggest that metal-rich halo stars were formed with a Li abundance close to the primordial value, and that lithium in their atmospheres has been depleted in time with an approximately linear dependence on stellar mass and Z. The lack of a systematic difference in the Li abundances of high- and low-alpha stars indicates that an environmental effect is not important for the destruction of lithium.Comment: 10 pages, 7 figures, accepted for publication in Astronomy and Astrophysic

Stavovi obiteljskih liječnika o elektroničkim alatima i dostupnosti, uporabi i pridržavanju smjernica za prevenciju kardiovaskularnih bolesti u Hrvatskoj

Family physicians are burdened with a great number of guidelines considering different conditions they treat. We analyzed opinions of family physicians on electronic tools which help managing chronic conditions and their influence on patient care by cardiovascular disease (CVD) prevention guideline availability, usage and adherence. A descriptive study was performed on a convenient sample of 417 (response rate 56.0%) Croatian family physicians. Data on physician characteristics and availability, usage and adherence to CVD prevention guidelines were analyzed. The χ2-test was used for comparisons. Significance was defined as p<0.05. Family physicians who used additional electronic tools in Electronic Health Record software on more than 80% of their patients had CVD prevention guidelines more available (p<0.01) and used them more frequently (p<0.01). A group who used electronic tools on more than 80% of their patients had CVD prevention guidelines available to them frequently and used them on more than 60% of their patients, also strictly adhering to the guidelines (p<0.01). Physicians who used CVD prevention guidelines on more than 60% of their patients spent more time doing patient education (p=0.036). Using electronic tools helps Croatian family physicians in terms of availability, usage and adherence to the guidelines and quality improvement.Obiteljski liječnici su u radu opterećeni velikim brojem smjernica za različite bolesti. Analizirali smo njihovo mišljenje o elektroničkim alatima koji im pomažu u skrbi za bolesnike s kroničnim bolestima i njihovom utjecaju na dostupnost, uporabu i pridržavanje smjernica za prevenciju kardiovaskularnih bolesti (KVB). Provedeno je opisno istraživanje na uzorku od 417 (stopa odgovora 56,0%) hrvatskih obiteljskih liječnika. Analizirani su podaci o značajkama liječnika, dostupnosti, upotrebi i pridržavanju smjernica za prevenciju KVB. Za usporedbe je primijenjen χ2-test. Statistička značajnost je definirana kao p<0,05. Obiteljski liječnici koji su rabili dodatne elektroničke alate za više od 80% svojih bolesnika imali su dostupnije smjernice za prevenciju KVB (p<0,01) i više su ih upotrebljavali (p<0,01). Liječnici koji su istodobno rabili elektroničke alate na više od 80% svojih bolesnika često su imali na raspolaganju smjernice za prevenciju KVB i upotrebljavali su ih na više od 60% svojih bolesnika, a ujedno su se strogo pridržavali smjernica (p<0,01). Liječnici koji su rabili smjernice za prevenciju KVB na više od 60% svojih bolesnika proveli su i više vremena obrazujući svoje bolesnike (p=0,036). Primjena elektroničkih alata pomaže obiteljskim liječnicima u Hrvatskoj u pogledu dostupnosti, upotrebe i pridržavanja smjernica te unaprjeđenju kvalitete skrbi

Impact of physical and biological processes on temporal variations of the ocean carbon sink in the mid-latitude North Atlantic (2002–2016)

The ocean is currently a significant net sink for anthropogenically remobilised CO2, taking up around 24% of global emissions. Numerical models predict a diversity of responses of the ocean carbon sink to increased atmospheric concentrations in a warmer world. Here, we tested the hypothesis that increased atmospheric forcing is causing a change in the ocean carbon sink using a high frequency observational dataset derived from underway pCO2 (carbon dioxide partial pressure) instruments on ships of opportunity (SOO) and a fixed-point mooring between 2002 and 2016. We calculated an average carbon flux of 0.013 Pg yr−1 into the ocean at the Porcupine Abyssal Plain (PAP) site, consistent with past estimates. In spite of the increase in atmospheric pCO2, monthly average seawater pCO2 did not show a statistically significant increasing trend, but a higher annual variability, likely due to the decreasing buffer capacity of the system. The increasing led to an increasing trend in the estimated CO2 flux into the ocean of 0.19 ± 0.03 mmol m−2 day−1 per year across the entire 15 year time series, making the study area a stronger carbon sink. Seawater pCO2 variability is mostly influenced by temperature, alkalinity and dissolved inorganic carbon (DIC) changes, with 77% of the annual seawater pCO2 changes explained by these terms. DIC is in turn influenced by gas exchange and biological production. In an average year, the DIC drawdown by biological production, as determined from nitrate uptake, was higher than the DIC increase due to atmospheric CO2 dissolution into the surface ocean. This effect was enhanced in years with high nutrient input or shallow mixed layers. Using the rate of change of DIC and nitrate, we observed Redfieldian carbon consumption during the spring bloom at a C:N ratio of 6.2 ± 1.6. A comparison between SOO and PAP sustained observatory data revealed a strong agreement for pCO2 and DIC. This work demonstrates that the study area has continued to absorb atmospheric CO2 in recent years with this sink enhancing over time. Furthermore, the change in pCO2 per unit nitrate became larger as surface buffer capacity changed