86 research outputs found

    Demonstration of the COBRA Teardrop Concept using Two Smallsats in 8-Hour Elliptic Orbits

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    Space Resource America Corporation is engaged in developing new concepts for communications satellite systems that will avoid interference with any of the Geostationary satellites and can provide a significant increase in global capacity compared with that of the GEO ring. Additionally, since all satellites in such a system are flying in formation, they will not interfere with each other. The company has filed for a series of patents on the orbital arrays, or constellations, that appear to hold the most promise in satisfying both commercial and government requirements. Each of the three active arcs of a single 8-hour satellite has a ground trace that resembles a coiled COBRA, and the orbits were so named. The acronym-like name COBRA was later amplified to “Communications Orbiting Broadband Repeating Arrays”. One of these arrays employs six 8-hour period leaning elliptical orbit satellites describing three continuous closed paths in the Northern Hemisphere. Ground antennas follow these satellites as their active arcs describe a repeating teardrop-shaped closed path in the sky. The tracking rate is very slow- averaging about 10 degrees/hour. It is possible to demonstrate all of the features of this array, however, with only two satellites. SRA is planning such a demonstration using two smallsats with a limited broadband communications payload. The communications payload will operate at Ku band or higher. The repeating ground tracks of this planned satellite duo will allow for an 8-hour demonstration daily in each of three Northern Hemisphere regions. The three teardrop shaped loops are separated in longitude by 120 degrees. One teardrop is centered upon the United States, the second on Japan and eastern China, and the third on central Europe. Conveniently, each regional demonstration will begin and end at the same local time of day. The use of smallsats for this demonstration is very desirable, in order to hold down costs of both satellites and launch vehicles. The design lifetime of the satellites will be approximately six months to a year, with the satellites being de-orbited at the appropriate time

    The Diversion of Prescription Drugs by Health Care Workers in Cincinnati, Ohio

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    Data are reported from drug diversion cases involving health care workers who were investigated by the Cincinnati Police Division Pharmaceutical Diversion Squad over an 11-year period. This type of information is rarely available because few U.S. police jurisdictions dedicate resources to prescription drug diversion surveillance. Data from 1992 through 2002 show that opioids were the drugs most commonly diverted by health care workers, followed by benzodiazepines. Nurses, nursing assistants, and medical assistants were involved in almost three quarters of all cases. Hospitals were the most common sources of complaint to police, followed by pharmacies. Health care professional associations are advised to promote greater awareness of drug misuse and dependence concerns among their memberships, and health care facilities that stock pharmaceuticals liable for misuse and diversion are advised to increase the security of their supplies

    Antifungal prophylaxis in chemotherapy-associated neutropenia: a retrospective, observational study

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    <p>Abstract</p> <p>Background</p> <p>In August 2002, the antifungal prophylaxis algorithm for neutropenic hematology/oncology (NHO) patients at the Medical Center was changed from conventional amphotericin (AMB) to an azole (AZ) based regimen (fluconazole [FLU] in low-risk and voriconazole [VOR] in high-risk patients). The aim of our study was to compare outcomes associated with the two regimens, including breakthrough fungal infection, adverse drug events, and costs.</p> <p>Methods</p> <p>Adult, non-febrile, NHO patients who received prophylactic AMB from 8/01/01-7/30/02 or AZ from 8/01/02-7/30/03 were retrospectively evaluated.</p> <p>Results</p> <p>A total of 370 patients (AMB: n = 181; AZ: n = 216) associated with 580 hospitalizations (AMB: n = 259; AZ: n = 321) were included. The incidence of probable/definite breakthrough Aspergillus infections was similar among regimens (AMB: 1.9% vs AZ: 0.6%; p=0.19). A greater incidence of mild/moderate (24.7% vs. 5.3%; p < 0.0001) and severe renal dysfunction (13.5% vs. 4.4%; p < 0.0012) was observed with AMB. In contrast, patients treated with VOR were found to have an increased rate of severe hepatic toxicity (32.5%) compared with patients treated with either AMB (22.6%) or FLU (21.4%) (p = 0.05). While the AZ period was associated with a >9,000increaseinmeantotalcosts/hospitalization,themeanacquisitioncostassociatedwithAZwasonly9,000 increase in mean total costs/hospitalization, the mean acquisition cost associated with AZ was only 947/hospitalization more than AMB.</p> <p>Conclusion</p> <p>While an AZ-based regimen is associated with increased cost, the reduced rate of nephrotoxicity and availability of oral dosage forms, suggests that azoles be used preferentially over AMB. However, an increased rate of severe hepatic toxicity may be associated with VOR.</p

    Prevalence and temporal trends of crack injection among injection drug users in eastern central Canada

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    Background: Little is known about crack injection and its temporal trends in North America. This article describes the extent of crack injection and examines temporal trends among injection drug users (IDUs) recruited from 2003 to 2010 in the SurvUDI network. Methods: IDUs who injected recently (past 6 months) were recruited in harm reduction and health programs in eastern central Canada. Trend analyses were performed using generalized estimating equations. Some IDUs participated multiple times; first interview was retained for the descriptive analyses, while first interview per year was retained for the trend analyses. Results: Of the 4088 IDUs recruited, 15.2% (621) reported crack injection; large variations across sites were noted (range: 0.3%-39.5%). Trend analyses were limited to Ottawa (449 crack injectors) and Montréal (121). For Ottawa, a significant decline was observed, from 48.3% to 36.9%, with a prevalence ratio (PR) of 0.97 per year (95%CI: 0.94-0.99). For Montréal, a significant rise was observed, from 6.0% to 18.4%, with a PR of 1.29 per year (95%CI: 1.19-1.40). Conclusions: Strong variations in crack injection exist throughout the SurvUDI network, and reversed temporal trends have been observed in Ottawa and Montréal. These data will be useful to local harm reduction programs to evaluate the need to distribute items required by crack injectors and to develop prevention messages

    Misdemeanor crime : trivial criminal pursuit

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    Volume 4197 p.; 20 cm

    Automated Breast Ultrasound in Breast Cancer Screening of Women With Dense Breasts: Reader Study of Mammography-Negative and Mammography-Positive Cancers.

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    © 2016 American Roentgen Ray Society. OBJECTIVE. The objective of our study was to assess and compare, in a reader study, radiologists\u27 performance in the detection of breast cancer using full-field digital mammography (FFDM) alone and using FFDM with 3D automated breast ultrasound (ABUS). MATERIALS AND METHODS. In this multireader, multicase, sequential-design reader study, 17 Mammography Quality Standards Act-qualified radiologists interpreted a cancerenriched set of FFDM and ABUS examinations. All imaging studies were of asymptomatic women with BI-RADS C or D breast density. Readers first interpreted FFDM alone and subsequently interpreted FFDM combined with ABUS. The analysis included 185 cases: 133 noncancers and 52 biopsy-proven cancers. Of the 52 cancer cases, the screening FFDM images were interpreted as showing BI-RADS 1 or 2 findings in 31 cases and BI-RADS 0 findings in 21 cases. For the cases interpreted as BI-RADS 0, a forced BI-RADS score was also given. Reader performance was compared in terms of AUC under the ROC curve, sensitivity, and specificity. RESULTS. The AUC was 0.72 for FFDM alone and 0.82 for FFDM combined with ABUS, yielding a statistically significant 14% relative improvement in AUC (i.e., change in AUC = 0.10 [95% CI, 0.07-0.14]; p \u3c 0.001). When a cutpoint of BI-RADS 3 was used, the sensitivity across all readers was 57.5% for FFDM alone and 74.1% for FFDM with ABUS, yielding a statistically significant increase in sensitivity (p \u3c 0.001) (relative increase = 29%). Overall specificity was 78.1% for FFDM alone and 76.1% for FFDM with ABUS (p = 0.496). For only the mammography-negative cancers, the average AUC was 0.60 for FFDM alone and 0.75 for FFDM with ABUS, yielding a statistically significant 25% relative improvement in AUC with the addition of ABUS (p \u3c 0.001). CONCLUSION. Combining mammography with ABUS, compared with mammography alone, significantly improved readers\u27 detection of breast cancers in women with dense breast tissue without substantially affecting specificity
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