7,010 research outputs found
FORTRAN 4 digital program changer
Computer program modifies other source language programs as aid to debugging, checkout and final documentation to eliminate manual performance of rearranging and incrementing statement numbers, identifying and sequencing cards and inserting and/or removing end-of-batch symbols
Modeling the physical properties in the ISM of the low-metallicity galaxy NGC4214
We present a model for the interstellar medium of NGC4214 with the objective
to probe the physical conditions in the two main star-forming regions and their
connection with the star formation activity of the galaxy. We used the spectral
synthesis code Cloudy to model an HII region and the associated
photodissociation region (PDR) to reproduce the emission of mid- and
far-infrared fine-structure cooling lines from the Spitzer and Herschel space
telescopes for these two regions. Input parameters of the model, such as
elemental abundances and star formation history, are guided by earlier studies
of the galaxy, and we investigated the effect of the mode in which star
formation takes place (bursty or continuous) on the line emission. Furthermore,
we tested the effect of adding pressure support with magnetic fields and
turbulence on the line predictions. We find that this model can satisfactorily
predict (within a factor of ~2) all observed lines that originate from the
ionized medium ([SIV] 10.5um, [NeIII] 15.6um, [SIII] 18.7um, [SIII] 33.5um, and
[OIII] 88um), with the exception of [NeII] 12.8um and [NII] 122um, which may
arise from a lower ionization medium. In the PDR, the [OI] 63um, [OI] 145um,
and [CII] 157um lines are matched within a factor of ~5 and work better when
weak pressure support is added to the thermal pressure or when the PDR clouds
are placed farther away from the HII regions and have covering factors lower
than unity. Our models of the HII region agree with different evolutionary
stages found in previous studies, with a more evolved, diffuse central region,
and a younger, more compact southern region. However, the local PDR conditions
are averaged out on the 175 pc scales that we probe and do not reflect
differences observed in the star formation properties of the two regions.Comment: accepted for publication in A&
Rotor and control system loads analysis of the XV-15 with the advanced technology blades
An analysis of the rotor and control system loads of the XV-15 with the Advanced Technology Blades (XV-15/ATB) was conducted to study the effects of modifications designed to alleviate high collective actuator loads encountered during initial flight tests. Rotor loads predictions were correlated with flight data to establish accuracies of the methodology used in the analysis. Control system loads predictions were then examined and were also correlated with flight data. The results showed a significant reduction in 3/rev collective actuator loads of the XV-15/ATB when the control system stiffness was increased and the rotor blade chord balance and tip twist were modified
Supermarkets: their effect on the ice cream industry.
Thesis (M.B.A.)--Boston Universit
The search for novel analgesics: re-examining spinal cord circuits with new tools
In this perspective, we propose the absence of detailed information regarding spinal cord
circuits that process sensory information remains a major barrier to advancing analgesia.
We highlight recent advances showing that functionally discrete populations of neurons in
the spinal cord dorsal horn play distinct roles in processing sensory information. We then
discuss new molecular, electrophysiological, and optogenetic techniques that can be
employed to understand how dorsal horn circuits process tactile and nociceptive
information. We believe this information can drive the development of entirely new classes
of pharmacotherapies that target key elements in spinal circuits to selectively modify
sensory function and blunt pain
Changes in Income Inequality within U.S. Metropolitan Areas
In studying MSA data that link the characteristics of metropolitan economies to significant changes in income inequality, Madden is able to study changes in poverty rates, household income inequality, and wage inequality within 182 of the largest MSAs and to identify what she says are the three factors most likely to influence changes in income inequality in metropolitan areas.https://research.upjohn.org/up_press/1060/thumbnail.jp
Has the Concentration of Income and Poverty among Subsurbs of Large US Metropolitan Areas Changed over Time?
American policy analysts have assumed that poverty is increasingly concentrating in the inner suburbs of large cities. This study demonstrates that that assumption is inaccurate. Using data on household income and poverty for suburban civil divisions from the 1970, 1980, and 1990 US Censuses, this article calculates values for two indicators of the change in the relative concentration of income and poverty, the coefficient of variation, and a regression of changes on initial values. Results indicate that poverty and income concentrations have not generally increased among suburbs over the last twenty years. There is evidence, however, that poverty has increasingly concentrated within some suburban municipalities of older metropolitan areas in the northeast and midwest
Effect of Staff Training and Cost Support on Provision of Long-Acting Reversible Contraception in Community Health Centers
Objective
To compare the proportion of women receiving same-day long-acting reversible contraception (LARC) between two different models of contraceptive provision adapted from the Contraceptive CHOICE Project.
Study Design
We used a controlled time-trend study design to compare 502 women receiving structured contraceptive counseling in addition to usual care (“Enhanced Care”) to 506 women receiving counseling plus healthcare provider education and cost support for LARC (“Complete CHOICE”) at three federally qualified health centers. We provided funds to health centers to ensure an “on-the-shelf” supply and no-cost LARC for uninsured women. We recorded the contraceptive method chosen after contraceptive counseling and the healthcare provider appointment as well as the contraceptive method received that day. Among women choosing LARC, we calculated proportions and performed Poisson regression with robust error variance to estimate relative risks for same-day insertion.
Results
Participant demographics reflected the health center populations; 69% were black, 66% had a high school diploma or less, 57% were publicly insured, and 75% reported household income less than 101% federal poverty line. There were 153 (30.5%) women in “Enhanced Care” and 273 (54.0%) in “Complete CHOICE” who chose LARC (p<0.01). Among women who chose LARC (n=426), those in “Complete CHOICE” were more likely to receive a same-day insertion, 53.8% vs. 13.7% (RRadj 4.73; 95%CI 3.20-6.98) compared to “Enhanced Care.”
Conclusions
A contraceptive care model that included healthcare provider education and cost support for LARC in addition to structured contraceptive counseling resulted in higher rates of same-day LARC insertion compared to contraceptive counseling and usual care alone
Performance-Support Bias and the Gender Pay Gap among Stockbrokers
Organizational mechanisms, and their contexts, leading to gender inequality among stockbrokers in two large brokerages are analyzed. Inequality is the result of gender differences in sales, as both firms use performance-based pay, paying entirely by commissions. This paper develops and tests whether performance-support bias, whereby women receive inferior sales support and sales assignments, causes the commissions gap. Newly available data on the brokerages’ internal transfers of accounts among brokers allows measurement of performance-support bias. Gender differences in the quality and quantity of transferred accounts provide a way to measure gender differences in the assignment of sales opportunities and support. Sales generated from internally transferred accounts, controlling for the accounts’ sales histories, provide a “natural experiment” testing for gender differences in sales capacities. The evidence for performance-support bias is: (1) women are assigned inferior accounts; and (2) women produce sales equivalent to men when given accounts with equivalent prior sales histories
Early germination physiology in hybrid maize (Zea mays L.) embryos damaged by high-temperature desiccation
Artificial drying of hybrid maize (Zea mays L.) seed using air temperatures in excess of 40°C can reduce seed vigor without affecting viability. Seed that was dried using high-temperature (45°C) air exhibited lower early seedling dry weight accumulation when compared to low-temperature (35°C) treatments. In embryo culture experiments, an extended germination period was observed for excised embryos from high-temperature (HT) treatments compared to low-temperature (LT). This observation coincided with reduced respiration rates for imbibing axis tissue from HT samples. In addition, uptake rates continued to increase for LT samples through the first 6 h of imbibition while rates for HT axes were constant. Mitochondria isolated from HT treated axis tissue that had been imbibed for 4 h exhibited no respiratory control. However, ADP/O values of 0.79 and 0.77 were recorded for NADH and succinate assays, respectively, for mitochondria from LT treated axes. Electron micrographs of cells from the radicle meristem region showed that mitochondrial development during the initial 24 h of imbibition was impaired in HT treated samples compared to LT tissue. A visible disruption of the matrix structure in HT tissue after 0 and 6 h of imbibition resulted in the apparent degeneration of some mitochondria at 24 h while others appear to have achieved repair. Analysis of nucleotide extracts of imbibed axis tissue by high performance liquid chromatography showed lower triphosphate nucleoside levels in HT samples. After 2 h of imbibition in air-saturated water, ATP levels in LT samples had increased dramatically and were 45% larger than HT treatments. Though ATP levels increased in HT treated tissue through 6 h of imbibition, the pool size did not attain the level measured for LT samples at 2 h. A reduced capacity for de novo synthesis of adenine nucleotides was also evident in the HT samples with total adenylates increasing only slightly in the first 6 h of imbibition. Adenylate energy charge values for LT samples after 4 h of 0.87 were consistent with metabolically active tissue while HT samples did not attain the same energy status. These results indicate that mitochondrial function, during the initial stages of embryonic tissue hydration, is a key element in determining the rate of germination (whole seed) and subsequent seedling growth
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