2,580 research outputs found
The economy and efficiency of a milking machine
Industry has progressed considerably in substituting mechanical appliances for hand labor, thereby vastly reducing unit production costs. In more recent years agriculture has been making wider uses of mechanical equipment with the result that production has been increased, altho the proportion of agricultural laborers has markedly declined. Kinsman1 states that within the last 75 years a man\u27s ability as a field worker on the farm has been trebled. As the future of agriculture is studied it seems likely that the greatest opportunity for reducing production costs is to increase the output per man thru mechanical equipment. It is with a hope of lessening labor costs that mechanical milkers are now being installed on numerous dairy farms
Effectiveness of bilateral tubotubal anastomosis in a large outpatient population
Is bilateral tubotubal anastomosis a successful treatment in an outpatient patient population
Soil-Transmitted Helminthiases: Implications of Climate Change and Human Behavior
Soil-transmitted helminthiases (STHs) collectively cause the highest global burden of parasitic disease after malaria and are most prevalent in the poorest communities, especially in sub-Saharan Africa. Climate change is predicted to alter the physical environment through cumulative impacts of warming and extreme fluctuations in temperature and precipitation, with cascading effects on human health and wellbeing, food security and socioeconomic infrastructure. Understanding how the spectrum of climate change effects will influence STHs is therefore of critical importance to the control of the global burden of human parasitic disease. Realistic progress in the global control of STH in a changing climate requires a multidisciplinary approach that includes the sciences (e.g. thermal thresholds for parasite development and resilience) and social sciences (e.g. behavior and implementation of education and sanitation programs)
Dual effects of implicit bystanders: Inhibiting vs. facilitating helping behavior
Encouraging consumers to engage in helpful behavior is a perennial task of marketers in non‐profit and for‐profit organizations. Recent research suggests that merely imagining the presence of others can lead to less helping behavior on a subsequent unrelated task (Garcia, S.M., Weaver, K.D., Moskowitz, G.B., and Darley, J.M. (2002). Crowded minds: The implicit bystander effect. Journal of Personality and Social Psychology, 83, 843–853.). The present analysis uncovers the boundary conditions of this effect. Across four studies, we establish that the degree to which a group situation fosters public scrutiny is an important moderator. When group primes are paired with public scrutiny, their inhibitive effect on helping behavior diminishes, and helping behavior on a subsequent task tends to increase. The present research thus adds complexity to previous findings by suggesting that implicit bystanders can both decrease and increase helping behavior.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142246/1/jcpy215.pd
Succulent feeds for dairy cows in summer
Profits in dairy operations are determined largely by the roughages available on a dairy farm. Successful dairymen plan feeding practices according to the roughages they have at hand. The kind and amount of grain they feed depends upon the roughage, being employed largely to supplement any possible deficiency in the roughages
Fitting Together the HI Absorption and Emission in the SGPS
In this paper we study 21-cm absorption spectra and the corresponding
emission spectra toward bright continuum sources in the test region (326deg< l
< 333 deg) of the Southern Galactic Plane Survey. This survey combines the high
resolution of the Australia Telescope Compact Array with the full brightness
temperature information of the Parkes single dish telescope. In particular, we
focus on the abundance and temperature of the cool atomic clouds in the inner
galaxy. The resulting mean opacity of the HI, , is measured as a
function of Galactic radius; it increases going in from the solar circle, to a
peak in the molecular ring of about four times its local value. This suggests
that the cool phase is more abundant there, and colder, than it is locally.
The distribution of cool phase temperatures is derived in three different
ways. The naive, ``spin temperature'' technique overestimates the cloud
temperatures, as expected. Using two alternative approaches we get good
agreement on a histogram of the cloud temperatures, T(cool), corrected for
blending with warm phase gas. The median temperature is about 65 K, but there
is a long tail reaching down to temperatures below 20 K. Clouds with
temperatures below 40 K are common, though not as common as warmer clouds (40
to 100 K).
Using these results we discuss two related quantities, the peak brightness
temperature seen in emission surveys, and the incidence of clouds seen in HI
self-absorption. Both phenomena match what would be expected based on our
measurements of and T(cool).Comment: 50 pages, 20 figure
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Serum Bovine Immunoglobulins Improve Inflammation and Gut Barrier Function in Persons with HIV and Enteropathy on Suppressive ART.
BackgroundSystemic inflammation persists in chronic HIV infection and is associated with increased rates of non-AIDS events such as cardiovascular and liver disease. Increased gut permeability and systemic exposure to microbial products are key drivers of this inflammation. Serum-derived bovine immunoglobulin/protein isolate (SBI) supports gut healing in other conditions such as inflammatory bowel disease.MethodsIn this randomized, double-blind study, participants receiving suppressive antiretroviral therapy (ART) with chronic diarrhea received placebo or SBI at 2.5 g BID or 5 g BID for 4 weeks, followed by a 20-week placebo-free extension phase with SBI at either 2.5 or 5 g BID. Intestinal fatty acid binding protein (I-FABP), zonulin, flagellin, lipopolysaccharide (LPS) and LPS-binding protein, and inflammatory markers were measured by ELISA or multiplex assays. Non-parametric tests were used for analysis.ResultsOne hundred three participants completed the study. By week 24 SBI significantly decreased circulating levels of I-FABP (-0.35 ng/μL, P=0.002) and zonulin (-4.90 ng/μL, P=0.003), suggesting improvement in gut damage, and interleukin-6 (IL-6) (-0.40 pg/μL, P=0.002), reflecting improvement in systemic inflammation. In participants with the lowest quartile of CD4+ T-cell counts at baseline (189-418 cells/μL), CD4+ T-cell counts increased significantly (26 cells/μL; P=0.002).ConclusionsOral SBI may decrease inflammation and warrants further exploration as a potential strategy to improve gut integrity and decrease systemic inflammation among persons receiving prolonged suppressive ART
The Nature and Frequency of the Gas Outbursts in Comet 67P/Churyumov-Gerasimenko observed by the Alice Far-ultraviolet Spectrograph on Rosetta
Alice is a far-ultraviolet imaging spectrograph onboard Rosetta that, amongst
multiple objectives, is designed to observe emissions from various atomic and
molecular species from within the coma of comet 67P/Churyumov-Gerasimenko. The
initial observations, made following orbit insertion in August 2014, showed
emissions of atomic hydrogen and oxygen spatially localized close to the
nucleus and attributed to photoelectron impact dissociation of H2O vapor.
Weaker emissions from atomic carbon were subsequently detected and also
attributed to electron impact dissociation, of CO2, the relative H I and C I
line intensities reflecting the variation of CO2 to H2O column abundance along
the line-of-sight through the coma. Beginning in mid-April 2015, Alice
sporadically observed a number of outbursts above the sunward limb
characterized by sudden increases in the atomic emissions, particularly the
semi-forbidden O I 1356 multiplet, over a period of 10-30 minutes, without a
corresponding enhancement in long wavelength solar reflected light
characteristic of dust production. A large increase in the brightness ratio O I
1356/O I 1304 suggests O2 as the principal source of the additional gas. These
outbursts do not correlate with any of the visible images of outbursts taken
with either OSIRIS or the navigation camera. Beginning in June 2015 the nature
of the Alice spectrum changed considerably with CO Fourth Positive band
emission observed continuously, varying with pointing but otherwise fairly
constant in time. However, CO does not appear to be a major driver of any of
the observed outbursts.Comment: 6 pages, 4 figures, accepted for publication in the Astrophysical
Journal Letter
Flexible Models for Solar Sail Control
Solar sails employ a unique form of propulsion, gaining momentum from incident and reflected photons. However, the momentum transferred by an individual photon is extremely small. Consequently, a solar sail must have an extremely large surface area and also be extremely light. The flexibility of the sail then must be considered when designing or evaluating control laws. In this paper, solar sail flexibility and its influence on control effectiveness is considered using idealized two-dimensional models to represent physical phenomena rather than a specific design. Differential equations of motion are derived for a distributed parameter model of a flexible solar sail idealized as a rotating central hub with two opposing flexible booms. This idealization is appropriate for solar sail designs in which the vibrational modes of the sail and supporting booms move together allowing the sail mass to be distributed along the booms in the idealized model. A reduced analytical model of the flexible response is considered. Linear feedback torque control is applied at the central hub. Two translational disturbances and a torque disturbance also act at the central hub representing the equivalent effect of deflecting sail shape about a reference line. Transient simulations explore different control designs and their effectiveness for controlling orientation, for reducing flexible motion and for disturbance rejection. A second model also is developed as a two-dimensional "pathfinder" model to calculate the effect of solar sail shape on the resultant thrust, in-plane force and torque at the hub. The analysis is then extended to larger models using the finite element method. The finite element modeling approach is verified by comparing results from a two-dimensional finite element model with those from the analytical model. The utility of the finite element modeling approach for this application is then illustrated through examples based on a full finite element model
X-ray imaging of the Seyfert 2 galaxy Circinus with Chandra
We present results from the zeroth-order imaging of a Chandra HETGS
observation of the nearby Seyfert 2 galaxy Circinus. Twelve X-ray sources were
detected in the ACIS-S image of the galaxy, embedded in diffuse X-ray emission.
The latter shows a prominent (~18arcsec) soft ``plume'' in the N-W direction,
coincident with the [OIII] ionization cone. The radial profiles of the
brightest X-ray source at various energies are consistent with an unresolved
(FWHM ~0.8arcsec) component, which we identify as the active nucleus, plus two
extended components with FWHMs ~ 2.3arcsec and 18arcsec, respectively. In a
radius of 3arcsec, the nucleus contributes roughly the same flux as the
extended components at the softest energies (< 2 keV). However, at harder
energies (> 2 keV), the contribution of the nucleus is dominant. The
zeroth-order ACIS spectrum of the nucleus exhibits emission lines at both soft
and hard X-rays, including a prominent Fe Kalpha line at 6.4 keV, showing that
most of the X-ray lines previously detected with ASCA originate in a compact
region (<15 pc). Based on its X-ray spectrum, we argue that the 2.3arcsec
extended component is scattered nuclear radiation from nearby ionized gas. The
large-scale extended component includes the emission from the N-W plume and
possibly from the outer starburst ring.Comment: Figure 1 in color. ApJ Letters, in pres
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