3,963 research outputs found
Deformation of generic submanifolds in a complex manifold
This paper shows that an arbitrary generic submanifold in a complex manifold
can be deformed into a 1-parameter family of generic submanifolds satisfying
strong nondegeneracy conditions. The proofs use a careful analysis of the jet
spaces of embeddings satisfying certain nondegeneracy properties, and also make
use of the Thom transversality theorem, as well as the stratification of
real-algebraic sets. Optimal results on the order of nondegeneracy are given.Comment: 24 page
The Unpaid Internship: Benefits, Drawbacks, and Legal Issues
This article hopes to clear up some of the confusion surrounding unpaid internships by discussing who participates in such internships, the merits and drawbacks relative to paid internships, and the relevant legal issues. This summary of existing research provides several key insights, which are of interest to potential interns as well as educators. For students, the literature suggests that unpaid internships are different from their paid counterparts in a variety of ways and pose certain risks that paid internships do not. On an institutional level, this paper documents the unique legal environment surrounding the unpaid internship and notes the unique liabilities program administrators may face if they fail to act with caution
Paleobiomarkers and defining exobiology experiments for future Mars experiments
Mars is a cold, dry planet with an oxidizing surface bombarded by ultraviolet and ionizing radiation, making prospects for an extant Mars biota bleak. Yet, it is suggested that early Earth and early Mars were similar enought that life may have evoled on Mars. If life did evolve on Mars, what evidence for its existence might we find? What constitutes a Martian paleobiomarker, and how can we distinguish such a marker from abiotically produced substances? The topics studied to answer this question include carbon and nitrogen cycling, as well as the stability and relative abundance of their intermediates in microbially dominated ecosystems. The microbially dominated ecosystems studied are the crytoendolithic microbial community living within sand rocks, the endoevaporite microbial community living inside salt crystals, and the microbial communities living beneath perennially ice-covered lakes and hypersaline ponds. The nitrogen cycle of these communities ranges from simple, where only assimilation occurs, to the more complex, where a complete cycle occurs. The carbon cycle of these communities appears to be complete
Emotional distress as a key construct in the personal model of diabetes management : associations of fatigue, diabetes-specific distress, and depressive symptomatology with quality of life in type 2 diabetes mellitus.
The importance of maximizing self-management and quality of life is well documented in the diabetes literature. Although maintaining self-care is known to be important for individuals with type 2 diabetes, this is often difficult to maintain over time. Emotional distress has also been shown to impact self-care behaviors in adults with type 2 diabetes. Glasgow et al (1997) introduced a model of key variables influencing diabetes self-management. This study examined specific emotional Personal Model constructs of diabetes management. Independent and converging lines of research have implicated several potentially overlapping constructs that may reflect emotional distress in persons living with diabetes including: fatigue, distress, and global depression that is specific to the demands of diabetes. These emotional distress constructs have all been linked to self-management behavior and quality of life in chronic disease. This study sought to explain the associations between these emotional constructs and their impact on self-management and quality of life. Questionnaire and medical chart review data were collected from adults (N=151) with type 2 diabetes at an outpatient diabetes clinic. Depressive symptomatology, diabetes-specific distress, and fatigue were found to be moderately associated with one another. Fatigue and diabetes specific distress were found to be associated with diet, mental, and physical quality of life. Findings suggest the Problem Areas In Diabetes scale (PAID) had the strongest association with diet adherence. Depressive symptomatology, diabetes-specific distress, and fatigue have a significant negative impact physical and mental quality of life. Future research should include the impact of fatigue on quality of life in adults with type 2 diabetes
Mapping of the Melatonin Receptor 1a (MTNR1A) Gene in Pigs, Sheep and Cattle
Human and sheep Melatonin receptor 1a (MTNR1A) gene information was used to clone a portion of the coding region of this gene in pigs, and to identify polymorphisms of the gene for its assignment to both the genetic linkage and physical maps. MTNR1A maps to pig chromosome 17, establishing a new region of conserved synteny between this chromosome and human chromosome 4. Furthermore, we have assigned MTNR1A to bovine chromosome 27 and sheep chromosome 26. The addition of genes like MTNR1A to livestock genome maps allows questions about evolutionary events and the genetic basis for quantitative traits in livestock to be addressed
Prediction Equations for Estimating Lean Quantity in 15- to 50-kg Pigs
Equations for predicting the quantity of lean in the young pig were developed from measurements on 48 pigs (16.8 to 48.5 kg body weight) representing four crossbred mating types; maternal breed(s) × maternal breed(s), paternal breed(s) × maternal breed(s), paternal breed(s) × paternal breed(s) and porcine stress-susceptible × mixed breed. Within litter and sex, each of three pigs was assigned randomly to a light, intermediate or heavy slaughter weight group such that each mating type was represented by six barrows and six gilts from four different litters. Thirteen measurements were obtained for each pig; body weight, body length, body circumference, front leg circumference, front leg length, shoulder depth, shoulder width, ham width, head width, shoulder fat, last rib fat, last lumbar fat and loin muscle depth. Fat measurements and loin depth were taken ultrasonically. Pigs were slaughtered, chilled and manually separated into lean and fat, bone, skin and feet and tail components. Fat composition was determined by the Goldfisch method and also an x-ray absorption procedure. Pigs averaged 32.0 kg body weight and 12.5 kg of lean. Prediction equations were developed by maximum R2 and stepwise regression procedures. The model that includes the 13 measured variables and average backfat produced a .97 R2 when predicting kilograms of lean (LWTA). Body weight was the only significant variable. The one-variable model of body weight (P\u3c.01) produced a .95 R2 Kilograms of lean was estimated for an additional 24 pigs using the one-variable model of body weight and the two-variable model of body weight and shoulder width. The variable LWTA was found to be highly correlated with both estimates of LWTA (r = .97). Results suggest that LWTA can be predicted using a simple model that could be adapted to applied situations
The MicroJansky Radio Galaxy Population
We use highly spectroscopically complete observations of the radio sources
from the VLA 1.4 GHz survey of the HDF-N region to study the faint radio galaxy
population and its evolution. We spectrally classify the sources into four
spectral types: absorbers, star formers, Seyfert galaxies, and broad-line AGNs,
and we analyze their properties by type. We supplement the spectroscopic
redshifts with photometric redshifts measured from the rest-frame UV to MIR
spectral energy distributions. Using deep X-ray observations of the field, we
do not confirm the existence of an X-ray-radio correlation for star-forming
galaxies. We also do not observe any correlations between 1.4 GHz flux and R
magnitude or redshift. We find that the radio powers of the host galaxies rise
dramatically with increasing redshift, while the optical properties of the host
galaxies show at most small changes. Assuming that the locally determined
FIR-radio correlation holds at high redshifts, we estimate total FIR
luminosities for the radio sources. We note that the FIR luminosity estimates
for any radio-loud AGNs will be overestimates. Considering only the radio
sources with quasar-like bolometric luminosities, we find a maximum ratio of
candidate highly-obscured AGNs to X-ray-luminous (>10^42 ergs/s) sources of
about 1.9. We use source-stacking analyses to measure the X-ray surface
brightnesses of various X-ray and radio populations. We find the contributions
to the 4-8 keV light from our candidate highly-obscured AGNs to be very small,
and hence these sources are unable to account for the light that has been
suggested may be missing at these energies.Comment: 20 pages, Accepted by The Astrophysical Journal (scheduled for 1 Jan
2007), color figures 2 and 3 can be found at
http://www.astro.wisc.edu/~barger/radiopaper.htm
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