4,775 research outputs found
The Therapeutic Camping Needs Of Children: The Hole-In-The-Hills At Wa-Shawtee
This executive summary of the preliminary report documents the major findings, to date, of the first two components of a needs assessment being conducted for the Hole in the Hills at Wa-Shawtee (HITH). The purpose of the study is to determine if a new, medically-equipped and professionally-staffed therapeutic camp in the Great Plains region of the Midwest has the capacity to be a success. There are almost 3.5 million children between the ages of five and seventeen in the 6-state HITH region, 1 an unknown number of whom are seriously-ill and/or have special medical conditions and health care needs, who could potentially benefit from a therapeutic camping facility.
The first two completed sections of the needs assessment are: 1) an inventory of existing camps and camp programs for selected pediatric conditions in the 6-state catchment area and 2) an inventory of the population to be served, including the prevalence of priority illnesses/conditions and the levels of unmet need or potential camp demand in the HITH region. The remaining two components of the assessment, which will be included in the final report are: 3) the identification and ranking of the needs of seriously-ill children in the priority disease groups, and 4) the identification and ranking of the needs of these children’s parents and families
Perturbations of a Universe Filled with Dust and Radiation
A first-order perturbation approach to Friedmann cosmologies filled
with dust and radiation is developed. Adopting the coordinate gauge comoving
with the perturbed matter, and neglecting the vorticity of the radiation, a
pair of coupled equations is obtained for the trace of the metric
perturbations and for the velocity potential . A power series solution with
upwards cutoff exists such that the leading terms for large values of the
dimensionless time agree with the relatively growing terms of the dust
solution of Sachs and Wolfe.Comment: 9 pp, typeset in late
Increased compensatory kidney workload results in cellular damage in a short time porcine model of mixed acidemia – Is acidemia a ‘first hit’ in acute kidney injury?
Acute kidney injury (AKI) corrupts the outcome of about 50% of all critically ill patients. We investigated the possible contribution of the pathology acidemia on the development of AKI. Pigs were exposed to acidemia, acidemia plus hypoxemia or a normal acid-base balance in an experimental setup, which included mechanical ventilation and renal replacement therapy to facilitate biotrauma caused by extracorporeal therapies. Interestingly, extensive histomorphological changes like a tubular loss of cell barriers occurred in the kidneys after just 5 hours exposure to acidemia. The additional exposure to hypoxemia aggravated these findings. These 'early' microscopic pathologies opposed intra vitam data of kidney function. They did not mirror cellular or systemic patterns of proinflammatory molecules (like TNF-α or IL 18) nor were they detectable by new, sensitive markers of AKI like Neutrophil gelatinase-associated lipocalin. Instead, the data suggest that the increased renal proton excretion during acidemia could be an 'early' first hit in the multifactorial pathogenesis of AKI
Fractal Analysis of Protein Potential Energy Landscapes
The fractal properties of the total potential energy V as a function of time
t are studied for a number of systems, including realistic models of proteins
(PPT, BPTI and myoglobin). The fractal dimension of V(t), characterized by the
exponent \gamma, is almost independent of temperature and increases with time,
more slowly the larger the protein. Perhaps the most striking observation of
this study is the apparent universality of the fractal dimension, which depends
only weakly on the type of molecular system. We explain this behavior by
assuming that fractality is caused by a self-generated dynamical noise, a
consequence of intermode coupling due to anharmonicity. Global topological
features of the potential energy landscape are found to have little effect on
the observed fractal behavior.Comment: 17 pages, single spaced, including 12 figure
Intensive Rotational Grazing of Steers on Highly Erodible Land at the Adams County CRP Project
Grazing yearling steers is one way to utilize the forages required for participation in the Conservation Reserve Program (CRP) after CRP contracts expire. In 1995, a stocker-steer intensive-rotational grazing study was conducted at the CRP Research and Demonstration Project near Corning, Iowa. A similar study was carried out in 1994. Seventy-five yearling crossbred steers grazed a 65- acre pasture that had been divided into 27 paddocks using electric fencing from May 4, 1995 to September 14, 1995. During this period, the 65-acre pasture system produced 9,975 animal-days of grazing and 11,403 pounds of gain. On a per-acre basis, this translates to 153.5 animal-days of grazing and 175.4 pounds of gain. The stocking rate was constant for the entire 133- day grazing season at 1.15 steers per acre. On May 4, 1995, the beginning of the grazing season, the average weight of the steers was 495.7 pounds. By the end of the grazing trial on September 14, 1995, the average weight of the steers had increased to 647.7 pounds. The average gain per steer during the 133-day grazing period was 152 pounds, and the average daily gain per steer was 1.14 pounds. The average bodyweight of the steers during the entire grazing season was 571.7 pounds
Epidermal Growth Factor–PEG Functionalized PAMAM-Pentaethylenehexamine Dendron for Targeted Gene Delivery Produced by Click Chemistry
Aim of this study was the site-specific conjugation of an epidermal growth factor (EGF)-polyethylene glycol (PEG) chain by click chemistry onto a poly(amido amine) (PAMAM) dendron, as a key step toward defined multifunctional carriers for targeted gene delivery. For this purpose, at first propargyl amine cored PAMAM dendrons with ester ends were synthesized. The chain terminal ester groups were then modified by oligoamines with different secondary amino densities. The oligoamine-modified PAMAM dendrons were well biocompatible, as demonstrated in cytotoxicity assays. Among the different oligoamine-modified dendrons, PAMAM-pentaethylenehexamine (PEHA) dendron polyplexes displayed the best gene transfer ability. Conjugation of PAMAM-PEHA dendron with PEG spacer was conducted via click reaction, which was performed before amidation with PEHA. The resultant PEG-PAMAM-PEHA copolymer was then coupled with EGF ligand. pDNA transfections in HuH-7 hepatocellular carcinoma cells showed a 10-fold higher efficiency with the polyplexes containing conjugated EGF as compared to the ligand-free ones, demonstrating the concept of ligand targeting. Overall gene transfer efficiencies, however, were moderate, suggesting that additional measures for overcoming subsequent intracellular bottlenecks in delivery have to be taken
A Rifted Margin Origin for the Crescent Basalts and Related Rocks in the Northern Coast Range Volcanic Province, Washington and British-Columbia
The remarkable early to middle Eocene volcanic sequence of the Crescent Formation exposed on the Olympic Peninsula consists predominantly of tholeiitic to minor transitional alkaline basalts with sparse sedimentary interbeds. A composite section measured in the vicinity of the Dosewallips River includes 8.4 km of pillowed to massive submarine basalts overlain by 7.8 km of subaerial flows. An upper limit of about 48 Ma on the age of the Crescent basalts is indicated by faunal assemblages in sediments interbedded with the uppermost flows in the sequence and a circa 50 Ma 40Ar/39Ar age on a leucogabbro from the presumably correlative Bremerton Igneous Complex. Stratigraphically controlled samples collected from throughout the Crescent basalt sequence show that two distinctly different chemical types exist. The lower part of the sequence originated from a relatively depleted mantle course resembling normal (N) to enriched (E)-MORB. The upper flows have a chemistry resembling E-MORB to oceanic island tholeiites. This difference could be due to either variable metasomatism of a single source domain, or influx of a separate enriched-mantle source component during the extrusion of the upper part of the sequence. Paleomagnetic measurements indicate that the Crescent basalts have not been significantly rotated, nor translated northwards since their extrusion. Paleotectonic reconstructions show that formation of the Crescent basalts and the Coast Range volcanic province as a whole coincided with a marked increase in the velocity of oblique convergence of the Kula plate with North America at about 60 Ma. Other geologic, geochemical, and paleomagnetic data are consistent with the interpretation that extrusion occurred in a basin or series of basins formed by a rift system along the continental margin of North America. Rifting might have been initiated by the influence of a hotspot, an increase in the rate of oblique convergence, or the kinematic effects of the Kula-Farallon ridge as it migrated along the margin. If extrusion is related to the passage of the triple junction, then the Coast Ranges can be considered to be an important tectonic marker for early to middle Eocene plate reconstructions
Sifting for Sapphires: Systematic Selection of Tidal Disruption Events in iPTF
We present results from a systematic selection of tidal disruption events
(TDEs) in a wide-area (4800~deg), band, Intermediate Palomar
Transient Factory (iPTF) experiment. Our selection targets typical
optically-selected TDEs: bright (60\% flux increase) and blue transients
residing in the center of red galaxies. Using photometric selection criteria to
down-select from a total of 493 nuclear transients to a sample of 26 sources,
we then use follow-up UV imaging with the Neil Gehrels Swift Telescope,
ground-based optical spectroscopy, and light curve fitting to classify them as
14 Type Ia supernovae (SNe Ia), 9 highly variable active galactic nuclei
(AGNs), 2 confirmed TDEs, and 1 potential core-collapse supernova. We find it
possible to filter AGNs by employing a more stringent transient color cut ( 0.2 mag); further, UV imaging is the best discriminator for filtering
SNe, since SNe Ia can appear as blue, optically, as TDEs in their early phases.
However, when UV-optical color is unavailable, higher precision astrometry can
also effectively reduce SNe contamination in the optical. Our most stringent
optical photometric selection criteria yields a 4.5:1 contamination rate,
allowing for a manageable number of TDE candidates for complete spectroscopic
follow-up and real-time classification in the ZTF era. We measure a TDE per
galaxy rate of 1.7 10 gal yr (90\%
CL in Poisson statistics). This does not account for TDEs outside our selection
criteria, thus may not reflect the total TDE population, which is yet to be
fully mapped.Comment: 24 pages, 21 figures. Accepted for publication in the Astrophysical
Journal Supplement Serie
Volume Expansion of Swiss-Cheese Universe
In order to investigate the effect of inhomogeneities on the volume expansion
of the universe, we study modified Swiss-Cheese universe model. Since this
model is an exact solution of Einstein equations, we can get an insight into
non-linear dynamics of inhomogeneous universe from it. We find that
inhomogeneities make the volume expansion slower than that of the background
Einstein-de Sitter universe when those can be regarded as small fluctuations in
the background universe. This result is consistent with the previous studies
based on the second order perturbation analysis. On the other hand, if the
inhomogeneities can not be treated as small perturbations, the volume expansion
of the universe depends on the type of fluctuations. Although the volume
expansion rate approaches to the background value asymptotically, the volume
itself can be finally arbitrarily smaller than the background one and can be
larger than that of the background but there is an upper bound on it.Comment: 22 pages, 7 figures, to be submitted to Phys. Rev.
Synthesis and Conformational Analysis of Locked Carbocyclic Analogues of 1,3-Diazepinone Riboside, a High-Affinity Cytidine Deaminase Inhibitor
Cytidine deaminase (CDA) catalyzes the deamination of cytidine via a hydrated transition-state intermediate that results from the nucleophilic attack of zinc-bound water at the active site. Nucleoside analogues where the leaving NH3 group is replaced by a proton and prevent conversion of the transition state to product are very potent inhibitors of the enzyme. However, stable carbocyclic versions of these analogues are less effective as the role of the ribose in facilitating formation of hydrated species is abolished. The discovery that a 1,3-diazepinone riboside (4) operated as a tight-binding inhibitor of CDA independent of hydration provided the opportunity to study novel inhibitors built as conformationally locked, carbocyclic 1,3-diazepinone nucleosides to determine the enzyme’s conformational preference for a specific form of sugar pucker. This work describes the synthesis of two target bicyclo[3.1.0]hexane nucleosides, locked as north (5) and south (6) conformers, as well as a flexible analogue (7) built with a cyclopentane ring. The seven-membered 1,3-diazepinone ring in all the three targets was built from the corresponding benzoyl-protected carbocyclic bis-allyl ureas by ring-closing metathesis. The results demonstrate CDA’s binding preference for a south sugar pucker in agreement with the high-resolution crystal structures of other CDA inhibitors bound at the active site
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