2,761 research outputs found
Farm land and debt situation in Iowa, 1935
Corporate-owned land amounted on January 1, 1935, to 10.1 percent of the 34 million acres of farm land in Iowa.
Insurance companies hold over half the corporate-owned land, with deposit banks the second largest holder.
Centers of concentration are in the south-central, north-central and a small area in the western part of the state.
The Iowa farm mortgage debt was reduced by 924,000,000, of which 40 percent is held by insurance companies, 26 percent by the Farm Credit Administration and 12 percent by banks The debt per acre was 66 in 1933. Since 1933 there has been a reduction of 2 percent in farm land mortgaged. (Forty-three percent is now mortgaged.
XBootes: An X-Ray Survey of the NDWFS Bootes Field - Paper I Overview and Initial Results
We obtained a 5 ksec deep Chandra X-ray Observatory ACIS-I map of the 9.3
square degree Bootes field of the NOAO Deep Wide-Field Survey. Here we describe
the data acquisition and analysis strategies leading to a catalog of 4642
(3293) point sources with 2 or more (4 or more) counts, corresponding to a
limiting flux of roughly 4(8)x10^{-15} erg cm^{-2}s^{-1} in the 0.5-7 keV band.
These Chandra XBootes data are unique in that they consitute the widest
contiguous X-ray field yet observed to such a faint flux limit. Because of the
extraordinarily low background of the ACIS, we expect only 14% (0.7%) of the
sources to be spurious. We also detected 43 extended sources in this survey.
The distribution of the point sources among the 126 pointings (ACIS-I has a 16
x 16 arcminute field of view) is consistent with Poisson fluctuations about the
mean of 36.8 sources per pointing. While a smoothed image of the point source
distribution is clumpy, there is no statistically significant evidence of large
scale filamentary structure. We do find however, that for theta>1 arcminute,
the angular correlation function of these sources is consistent with previous
measurements, following a power law in angle with slope -0.7. In a 1.4 deg^{2}
sample of the survey, approximately 87% of the sources with 4 or more counts
have an optical counterpart to R ~26 mag. As part of a larger program of
optical spectroscopy of the NDWFS Bootes area, spectra have been obtained for
\~900 of the X-ray sources, most of which are QSOs or AGN.Comment: 18 Pages, 10 figures (AASTex Preprint format
Pac13 is a small, monomeric dehydratase that mediates the formation of the 3′-deoxy nucleoside of pacidamycins
This work was supported by the EPSRC council (Grant number 1398501), Wellcome Trust (Investigator Award) and GlaxoSmithKline.The uridyl peptide antibiotics (UPAs), of which pacidamycin is a member, have a clinically unexploited mode of action and an unusual assembly. Perhaps the most striking feature of these molecules is the biosynthetically unique 3′-deoxyuridine that they share. This moiety is generated by an unusual, small and monomeric dehydratase, Pac13, which catalyses the dehydration of uridine-5’-aldehyde. Here we report the structural characterisation of Pac13 with a series of ligands, and gain insight into the enzyme’s mechanism demonstrating that H42 is critical to the enzyme’s activity and that the reaction is likely to proceed via an E1cB mechanism. The resemblance of the 3′-deoxy pacidamycin moiety with the synthetic anti-retrovirals, presents a potential opportunity for the utilisation of Pac13 in the biocatalytic generation of antiviral compounds.Publisher PDFPeer reviewe
The Chandra XBootes Survey - III: Optical and Near-IR Counterparts
The XBootes Survey is a 5-ks Chandra survey of the Bootes Field of the NOAO
Deep Wide-Field Survey (NDWFS). This survey is unique in that it is the largest
(9.3 deg^2), contiguous region imaged in X-ray with complementary deep optical
and near-IR observations. We present a catalog of the optical counterparts to
the 3,213 X-ray point sources detected in the XBootes survey. Using a Bayesian
identification scheme, we successfully identified optical counterparts for 98%
of the X-ray point sources. The optical colors suggest that the optically
detected galaxies are a combination of z<1 massive early-type galaxies and
bluer star-forming galaxies whose optical AGN emission is faint or obscured,
whereas the majority of the optically detected point sources are likely quasars
over a large redshift range. Our large area, X-ray bright, optically deep
survey enables us to select a large sub-sample of sources (773) with high X-ray
to optical flux ratios (f_x/f_o>10). These objects are likely high redshift
and/or dust obscured AGN. These sources have generally harder X-ray spectra
than sources with 0.1<f_x/f_o<10. Of the 73 X-ray sources with no optical
counterpart in the NDWFS catalog, 47 are truly optically blank down to R~25.5
(the average 50% completeness limit of the NDWFS R-band catalogs). These
sources are also likely to be high redshift and/or dust obscured AGN.Comment: 19 pages, 13 figures, ApJ accepted. Catalog can be found at:
http://www.noao.edu/noao/noaodeep or
ftp://archive.noao.edu/pub/catalogs/xbootes
Pressure radiation from a perforated duct exit region
Acknowledgements The authors are grateful to the following bodies that provided financial support for the project: (i) China Scholarship Council, (ii) National Natural Science Foundation of China (Grant no. U1334201) and (iii) UK Engineering and Physical Sciences Research Council (Grant no. EP/G069441/1).Peer reviewedPublisher PD
Etiology of Severe Non-malaria Febrile Illness in Northern Tanzania: A Prospective Cohort Study.
The syndrome of fever is a commonly presenting complaint among persons seeking healthcare in low-resource areas, yet the public health community has not approached fever in a comprehensive manner. In many areas, malaria is over-diagnosed, and patients without malaria have poor outcomes. We prospectively studied a cohort of 870 pediatric and adult febrile admissions to two hospitals in northern Tanzania over the period of one year using conventional standard diagnostic tests to establish fever etiology. Malaria was the clinical diagnosis for 528 (60.7%), but was the actual cause of fever in only 14 (1.6%). By contrast, bacterial, mycobacterial, and fungal bloodstream infections accounted for 85 (9.8%), 14 (1.6%), and 25 (2.9%) febrile admissions, respectively. Acute bacterial zoonoses were identified among 118 (26.2%) of febrile admissions; 16 (13.6%) had brucellosis, 40 (33.9%) leptospirosis, 24 (20.3%) had Q fever, 36 (30.5%) had spotted fever group rickettsioses, and 2 (1.8%) had typhus group rickettsioses. In addition, 55 (7.9%) participants had a confirmed acute arbovirus infection, all due to chikungunya. No patient had a bacterial zoonosis or an arbovirus infection included in the admission differential diagnosis. Malaria was uncommon and over-diagnosed, whereas invasive infections were underappreciated. Bacterial zoonoses and arbovirus infections were highly prevalent yet overlooked. An integrated approach to the syndrome of fever in resource-limited areas is needed to improve patient outcomes and to rationally target disease control efforts
Bostonia: The Boston University Alumni Magazine. Volume 12
Founded in 1900, Bostonia magazine is Boston University’s main alumni publication
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