1,832 research outputs found
State and local agencies are more effective than the federal government in housing discrimination enforcement
Discrimination by those selling or renting homes is illegal under the 1968 Fair Housing Act (known as Title VIII), but housing discrimination and segregation in the US have not been eliminated. Federal, state, and local agencies are responsible for enforcing Title VIII, so in which part of government is enforcement most effective? In new research which analyses data from the ..
Modified Appleby Procedure with Arterial Reconstruction for Locally Advanced Pancreatic Adenocarcinoma: A Literature Review and Report of Three Unusual Cases.
BACKGROUND: Pancreatic body and tail ductal adenocarcinomas are often diagnosed with local vascular invasion of the celiac axis (CA) and its various branches. With such involvement, these tumors have traditionally been considered unresectable. The modified Appleby procedure allows for margin negative resection of some such locally advanced tumors. This procedure involves distal pancreatectomy with en bloc splenectomy and CA resection and relies on the presence of collateral arterial circulation via an intact pancreaticoduodenal arcade and the gastroduodenal artery to maintain prograde hepatic arterial perfusion. When the resultant collateral circulation is inadequate to provide sufficient hepatic and gastric arterial inflow, arterial reconstruction (AR) is necessary to supercharge the inflow. Herein, we review all reported cases of AR with modified Appleby procedures that we have identified in the literature, and we report our experience of three recent cases with arterial reconstruction including two cases with arterial bypasses not requiring interposition grafting.
METHODS: Perioperative and oncologic outcomes from our Institutional Review Board-approved database of pancreatic resections at the Thomas Jefferson University were reviewed. Additionally, PubMed search for cases of distal or total pancreatectomy with celiac axis resection and concurrent AR was performed.
RESULTS: From the literature, 12 reports involving 28 patients were identified of distal and total pancreatectomy with AR after CA resection. The most common AR in the literature, performed in 12 patients, was a bypass from the aorta to the common hepatic artery (CHA) using a variety of interposition conduits. In our institutional experience, patient #1 had a primary side-to-end aorto-CHA bypass, patient #2 had a primary end-to-end bypass of the transected distal CHA to the left gastric artery in the setting a replaced left hepatic artery, and patient #3 required an aortic to proper hepatic artery bypass with saphenous vein graft and portal venous reconstruction. All patients recovered from their operations without ischemic complications, and they are currently 16, 15, and 13 months post-op, respectively.
CONCLUSIONS: The criteria for resectability in patients with locally advanced pancreatic body and tail neoplasms are expanding due to increasing experience with AR in the setting of the modified Appleby procedure. When performing AR, primary arterial re-anastomosis may be considered preferable to interposition grafting as it decreases the potential for the infectious and thrombotic complications associated with conduits and it reduces the number of vascular anastomoses from two to one. Consideration must also be given to normal variant anatomy of the hepatic circulation during operative planning as the origin of the left gastric artery is resected with the CA. The modified Appleby procedure with AR, when used in appropriately selected patients, offers the potential for safe, margin negative resection of locally advanced pancreatic body and tail tumors
Flash-Heating of Circumstellar Clouds by Gamma Ray Bursts
The blast-wave model for gamma-ray bursts (GRBs) has been called into
question by observations of spectra from GRBs that are harder than can be
produced through optically thin synchrotron emission. If GRBs originate from
the collapse of massive stars, then circumstellar clouds near burst sources
will be illuminated by intense gamma radiation, and the electrons in these
clouds will be rapidly scattered to energies as large as several hundred keV.
Low-energy photons that subsequently pass through the hot plasma will be
scattered to higher energies, hardening the intrisic spectrum. This effect
resolves the "line-of-death" objection to the synchrotron shock model.
Illuminated clouds near GRBs will form relativistic plasmas containing large
numbers of electron-positron pairs that can be detected within ~ 1-2 days of
the explosion before expanding and dissipating. Localized regions of pair
annihilation radiation in the Galaxy would reveal past GRB explosions.Comment: 9 pages, 1 figure, submitted to ApJ Letter
Hyperpycnal wave-modified turbidites of the Pennsylvanian Minturn Formation, north-central Colorado
The Pennsylvanian Minturn Formation in north-central Colorado exhibits a complex stratigraphic architecture of fan-delta deposits that developed in association with high
topographic relief in a tectonically active setting. The formation records a wide range of environments including alluvial fan, fluvial, deltaic, and open marine settings. This field trip will examine outcrops of a remarkable ~20 to 35-m-thick, unconformity-bound unit with turbidite-like
beds that presumably developed within the lower reaches of incised valleys. This unit consists of dark green shale and graded sandstone beds with tool marks produced by abundant
plant material. The sandstone event beds contain evidence for strong unidirectional flows and the variable influence of storm-generated waves. Proximal deposits contain beds with evidence for wave-dominated combined flows, including well developed, large-scale hummocky cross-stratification.
Distal sections contain beds with reverse-to-normal grading and vertical successions of sedimentary structures that indicate long-lived waxing-to-waning unidirectional
flows in conjunction with storm waves. We interpret these beds as a record of deposition from hyperpycnal flows, i.e., turbidity currents generated directly from highly concentrated river plumes, which waxed and waned in response to the rising and falling flood hydrograph. The focus of this trip will be the hydrodynamic interpretation of these different bed types, including their spatial and stratigraphic distribution
Valley formation and methane precipitation rates on Titan
Branching valley networks near the landing site of the Huygens probe on Titan imply that fluid has eroded the surface. The fluid was most likely methane, which forms several percent of Titan's atmosphere and can exist as a liquid at the surface. The morphology of the valley networks and the nature of Titan's surface environment are inconsistent with a primary valley formation process involving thermal, chemical, or seepage erosion. The valleys were more likely eroded mechanically by surface runoff associated with methane precipitation. If mechanical erosion did occur, the flows must first have been able to mobilize any sediment accumulated in the valleys. We develop a model that links precipitation, open-channel flow, and sediment transport to calculate the minimum precipitation rate required to mobilize sediment and initiate erosion. Using data from two monitored watersheds in the Alps, we show that the model is able to predict precipitation rates in small drainage basins on Earth. The calculated precipitation rate is most sensitive to the sediment grain size. For a grain diameter of 1–10 cm, a range that brackets the median size observed at the Huygens landing site, the minimum precipitation rate required to mobilize sediment in the nearby branching networks is 0.5–15 mm hr^(−1). We show that this range is reasonable given the abundance of methane in Titan's atmosphere. These minimum precipitation rates can be compared with observations of tropospheric cloud activity and estimates of long-term methane precipitation rates to further test the hypothesis that runoff eroded the valleys
The effect of follicular fluid hormones on oocyte recovery after ovarian stimulation: FSH level predicts oocyte recovery.
BackgroundOvarian stimulation for assisted reproductive technology (ART) overcomes the physiologic process to develop a single dominant follicle. However, following stimulation, egg recovery rates are not 100%. The objective of this study is to determine if the follicular fluid hormonal environment is associated with oocyte recovery.MethodsThis is a prospective study involving patients undergoing ART by standard ovarian stimulation protocols at an urban academic medical center. A total of 143 follicular fluid aspirates were collected from 80 patients. Concentrations of FSH, hCG, estradiol, progesterone, testosterone and prolactin were determined. A multivariable regression analysis was used to investigate the relationship between the follicular fluid hormones and oocyte recovery.ResultsIntrafollicular FSH was significantly associated with oocyte recovery after adjustment for hCG (Adjusted odds ratio (AOR) = 1.21, 95%CI 1.03-1.42). The hCG concentration alone, in the range tested, did not impact the odds of oocyte recovery (AOR = 0.99, 95%CI 0.93-1.07). Estradiol was significantly associated with oocyte recovery (AOR = 0.98, 95% CI 0.96-0.99). After adjustment for progesterone, the strength of association between FSH and oocyte recovery increased (AOR = 1.84, 95%CI 1.45-2.34).ConclusionThe relationship between FSH and oocyte recovery is significant and appears to work through mechanisms independent of the sex hormones. FSH may be important for the physiologic event of separation of the cumulus-oocyte complex from the follicle wall, thereby influencing oocyte recovery. Current methods for inducing the final stages of oocyte maturation, with hCG administration alone, may not be optimal. Modifications of treatment protocols utilizing additional FSH may enhance oocyte recovery
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IT Alignment with Business Strategies in Healthcare Organizations: An Empirical Analysis
This paper describes a study that assessed the performance implications of aligning information technology (IT) strategy to overall business strategy across a variety of health care organization (HCO) structures. We obtained survey results from senior executives of 178 hospitals to identify key configurations of IT strategic practices, business strategy and HCO structures. Using K- means cluster analysis, we identified which business strategies correlate strongly with certain IT strategy types. Our results indicate that HCOs achieve superior performance through unique combinations of business and IT strategy, suggesting that correctly aligning these strategies is a critical decision for healthcare organizations
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