Estimating Procurement Cost Growth Using Logistic and Multiple Regression

Cost Growth in Department of Defense (DoD) major systems has been an ongoing problems for more than 30 years. Previous research has demonstrated the use of two-step logistic and multiple regression methodology to predicting cost growth produces desirable results traditional single-step regression. This research effort validates, and further explores the use of a two-step procedure for assessing DoD major weapon system cost growth using historical data. We compile programmatic data from the Selected Acquisition Reports (SARs) between 1990 and 2001 for programs covering all defense departments. Our analysis concentrates on cost growth in procurement dollar accounts for the Engineering and Manufacturing Development phase of acquisition. We investigate the use of logistic regression in cost growth analysis to predict whether or not procurement cost growth will occur in a program. If applicable, the multiple regression step is implemented to predict how much procurement cost growth will occur. Our study considers all seven SAR categories within the procurement accounts - engineering, schedule, estimating, support, quantity, economic, and other, but we refrain from analyzing these categories individually. Consequently, we focus on the total procurement cost growth incurred from these five categories during the Engineering and Manufacturing Development phase of acquisition

Combining Taipan snake venom time/Ecarin time screening with the mixing studies of conventional assays increases detection rates of lupus anticoagulants in orally anticoagulated patients

<p>Abstract</p> <p>Background</p> <p>Oral anticoagulation compromises conventional lupus anticoagulant (LA) screening assays. Mixing studies can counteract the oral anticoagulant effect but the dilution reduces sensitivity and can generate false negative results. A firm diagnosis can be made from mixing studies when an elevated screen ratio is accompanied by a confirm ratio that generates significant correction to demonstrate phospholipid dependence, but also returns into the reference range, indicating complete normalisation of the oral anticoagulant effect. Taipan snake venom time (TSVT) with Ecarin time (ET) as a confirmatory test comprises an oral anticoagulant insensitive LA detection system and this study investigates the potential impact on detection rates when coupled with mixing studies on standard assays.</p> <p>Methods</p> <p>Eighty patients known to have LA who were receiving oral anticoagulation were tested with TSVT/ET and 1:1 mixing studies with normal plasma by dilute Russell's viper venom time (DRVVT) and dilute activated partial thromboplastin time (DAPTT) to assess detection rates by single and multiple assays.</p> <p>Results</p> <p>Thirty three of the 80 samples from known LA positive patients were positive in all three assays and 15 were positive in combinations of DRVVT, DAPTT or TSVT/ET. The remainder were positive in only one assay; 12 by DRVVT, 4 by DAPTT and 16 by TSVT/ET. Although all DRVVT and DAPTT positive mixing studies generated significant correction of the screen ratio by the confirm ratio, not all confirm ratios corrected back into the reference range. This was the case for 87.5% of the DRVVT results, 44.7% of the DAPTT results and 13.3% of the TSVT/ET positive mixing tests.</p> <p>Conclusion</p> <p>Addition of TSVT/ET screening for LA in orally anticoagulated patients could increase diagnostic efficacy either by detecting antibodies diluted in the mixing tests of conventional assays or those that do not react in DRVVT or DAPTT. Additionally, TSVT/ET can affirm the presence of a LA where conventional assay mixing tests may not have fully counteracted the oral anticoagulant effect but confirmatory test correction suggests the presence of a LA.</p

Analytical dilemmas in lupus anticoagulant detection

Accurate lupus anticoagulant (LA) detection is crucial to antiphospholipid syndrome (APS) diagnosis. Detection is based on LA functional behavior in coagulation assays irrespective of epitope specificity. LA screening tests employ dilute phospholipids to accentuate in vitro inhibition by LAs, although they are not LA-specific and can be elevated by other coagulation abnormalities. Elevated screening tests are reflexed to mixing tests to distinguish between factor deficiency and inhibition. Confirmatory tests with high phospholipid concentration swamp LA to generate shorter clotting times than screening tests, whilst prolongation persists with non-phospholipid-dependent inhibitors. LA heterogeneity means that no single screening test detects every LA and the screen/mix/confirm medley must be applied to at least two assay types, usually dilute Russell’s viper venom time (dRVVT) and an LA-sensitive activated partial thromboplastin time (aPTT). Most laboratories restrict LA testing to these two assays, yet others, such as dilute prothrombin time (dPT), can perform with equal diagnostic efficacy, and additionally detect LA unreactive with dRVVT and aPTT. Converting clotting times to normalized ratios improves assay performance, and practitioners must choose between normal pooled plasma (NPP) clotting time denominators to reflect on-the-day assay performance, or reference interval (RI) mean clotting times to negate the effects of NPP variation. Cut-offs can be generated parametrically from normally distributed data, or different percentiles applied depending on the preferred balance between sensitivity and specificity. Sourcing sufficient donors for accurate cut-off estimations is problematic and transference exercises can be undertaken on low donor numbers. Analytical limitations of mixing tests have led to the adoption of alternative algorithms to the screen/mix/confirm test order, whilst some continue to rigidly apply the latter despite those limitations. Strategies to reduce or eliminate the effects of therapeutic anticoagulation have limitations, whilst the Taipan snake venom time (TSVT) screening test with an ecarin time (ET) confirmatory test is insensitive to vitamin K antagonist (VKA) and direct activated factor X anticoagulation

Second Year Results from Razor C.O.A.C.H.

In this paper, we present the results of a random assignment evaluation on the Razor C.O.A.C.H. (Creating Opportunities for Arkansan’s Career Hopes) program. As the program started in the 2012-13 school year, this evaluation analyzes the impact of the program in its second year of operation and includes two cohorts of students. The focus of the comprehensive evaluation is the impacts of the program on students’ academic outcomes, short-term noncognitive outcomes, short-term college and career readiness outcomes, and post-secondary outcomes

Influence of \u3ci\u3eLysobacter enzymogenes\u3c/i\u3e Strain C3 on Nematodes

Chitinolytic microflora may contribute to biological control of plant-parasitic nematodes by causing decreased egg viability through degradation of egg shells. Here, the influence of Lysobacter enzymogenes strain C3 on Caenorhabditis elegans, Heterodera schachtii, Meloidogyne javanica, Pratylenchus penetrans, and Aphelenchoides fragariae is described. Exposure of C. elegans to L. enzymogenes strain C3 on agar resulted in almost complete elimination of egg production and death of 94% of hatched juveniles after 2 d. Hatch of H. schachtii eggs was about 50% on a lawn of L. enzymogenes strain C3 on agar as compared to 80% on a lawn of E. coli. Juveniles that hatched on a lawn of L. enzymogenes strain C3 on agar died due to disintegration of the cuticle and body contents. Meloidogyne javanica juveniles died after 4 d exposure to a 7-d-old chitin broth culture of L. enzymogenes strain C3. Immersion of A. fragariae, M. javanica, and P. penetrans juveniles and adults in a nutrient broth culture of L. enzymogenes strain C3 led to rapid death and disintegration of the nematodes. Upon exposure to L. enzymogenes strain C3 cultures in nutrient broth, H. schachtii juveniles were rapidly immobilized and then lysed after three days. The death and disintegration of the tested nematodes suggests that toxins and enzymes produced by this strain are active against a range of nematode species

A Completely New Type of Actuator -or- This Ain't Your Grandfather's Internal Combustion Engine

A completely new type of actuator - one that is proposed for use in a variety of environments from sea to land to air to space - has been designed, patented, built, and tested. The actuator is loosely based on the principle of the internal combustion engine, except that it is a completely closed system, only requiring electrical input, and the working fuel is water. This paper outlines the theory behind the electrolysis- and ignition-based cycle upon which the actuator operates and describes the performance capability test apparatus and results for the actuator. A mechanism application that harnessed the unit s power to twist a scaled rotor blade is also highlighted

Technical Changes in Paraspinous Muscle Flap Surgery Have Increased Salvage Rates of Infected Spinal Wounds

Objectives: The objective of this study is to introduce modifications in paraspinous muscle flap surgery and compare this new variation's ability to salvage infected hardware with the classic technique. Infected posterior spine wounds are a difficult problem for reconstructive surgeons. As per experience, hardware retention in infected wounds maintains spinal stability, decreases length of stay, and decreases the wound healing complication rate. Methods: An 11-year retrospective office and hospital chart review was conducted between July 1996 and August 2007. All patients who underwent paraspinous muscle flap reconstruction for postspine surgery wound infections during this time period were included. There were 51 patients in the study representing the largest reported series, to date, for this procedure. Twenty-two patients underwent treatment using the modified technique and 29 patients were treated using the classic technique. Results: There was no statistical difference between the 2 groups in demographics, medical history, or reason for initial spine surgery. The hardware salvage rate associated with the modified technique was greater than the rate associated with the classic technique (95.4% vs 75.8%; P = .03). There were fewer postreconstruction wound healing complications requiring hospital readmission in the modified technique group than the classic group (13.6% vs 44.8%; P = .04). Patients in the modified technique group demonstrated a shorter mean length of stay than the patients in the classic group (23.7 days vs 29.7; P = .25). Conclusions: The modified paraspinous muscle flap technique is an excellent option for spinal wound reconstruction, preservation of spinal hardware, and local infection control

Ecosystems as Commodity Frontiers - Challenges Faced by Land Set Aside as Protected Areas (PAs) in the Dubai Emirate, United Arab Emirates (UAE)

This chapter examines natural habitats in Dubai, UAE that the state has demarcated as protected areas (PAs) in an attempt to utilize them for recreational/economic purposes while also mitigating habitat fragmentation. The authors employ the concept of the ‘commodity frontier’ to demonstrate how these PAs have contributed to the ongoing commodification of land that began with the rise of modern agriculture in the mid-twentieth century. The rise of the oil economy in the mid-twentieth century stimulated significant development that, over time, has resulted in ecological degradation. In line with state conservation agendas aimed at greening the desert and preserving biodiversity, PAs also serve as a mechanism for promoting tourism. Ironically, these activities have in turn put further pressure on the country’s natural resources and desert ecology. The authors also present an example of a PA that has been effectively managed and could serve as a model of sustainable development

Direct oral anticoagulants-Remove versus Taipan snake venom time for detection of a lupus anticoagulant in patients taking oral direct factor Xa inhibitors.

BACKGROUND: The optimal method of detecting a lupus anticoagulant (LA) for patients taking direct factor Xa inhibitor (DFXaI) direct oral anticoagulants (DOACs) remains controversial. Methods include charcoal adsorption of the DOACs to allow testing with the activated partial thromboplastin time (APTT) and dilute Russell viper venom time (dRVVT), or use of the DFXaI-insensitive Taipan snake venom time (TSVT) and Ecarin time (ET) assays on neat plasma. OBJECTIVES: The objective was to compare the utility of APTT and dRVVT analysis following DOAC Remove against TSVT/ET on untreated plasma for LA detection in spiked plasmas and routine clinical samples for patients on DFXaIs. PATIENTS/METHODS: Various LA-negative and LA-positive samples were assayed by APTT, dRVVT, and TSVT/ET, and then separately spiked with rivaroxaban, apixaban, and edoxaban calibrators to a concentration of ~190 ng/ml and the assays repeated on spiked plasma before and after DOAC Remove treatment. Testing of 284 consecutive samples from DFXaI-anticoagulated patients by APTT/dRVVT and TSVT/ET before and after DOAC Remove treatment was undertaken. RESULTS: In the spiking model, we found that both TSVT/ET and DOAC Remove strategies generally distinguished LA-negative and LA-positive samples, but some false-positive LA results occurred. In the investigation of 284 consecutive patient samples on DFXaIs, the percentage agreement for LA detection in neat samples tested by TSVT/ET versus APTT and dRVVT after DOAC Remove treatment was 90% (Cohen kappa 0.12). CONCLUSION: Our data highlight uncertainty and disagreement for testing LA in patients on DFXaI. Further studies are required

Clinical Validation of an Automated Fluorogenic Factor XIII Activity Assay Based on Isopeptidase Activity.

Hereditary factor XIII (FXIII) deficiency is a rare autosomal bleeding disorder which can cause life-threatening bleeding. Acquired deficiency can be immune-mediated or due to increased consumption or reduced synthesis. The most commonly used screening test is insensitive, and widely used quantitative assays have analytical limitations. The present study sought to validate Technofluor FXIII Activity, the first isopeptidase-based assay available on a routine coagulation analyser, the Ceveron s100. Linearity was evidenced throughout the measuring range, with correlation coefficients of >0.99, and coefficients of variation for repeatability and reproducibility were <5% and <10%, respectively. A normally distributed reference range of 47.0-135.5 IU/dL was derived from 154 normal donors. Clinical samples with Technofluor FXIII Activity results between 0 and 167.0 IU/dL were assayed with Berichrom® FXIII Activity, a functional ammonia release assay, and the HemosIL™ FXIII antigen assay, generating correlations of 0.950 and 0.980, respectively. Experiments with a transglutaminase inhibitor showed that Technofluor FXIII Activity can detect inhibition of enzymatic activity. No interference was exhibited by high levels of haemolysis and lipaemia, and interference by bilirubin was evident at 18 mg/dL, a level commensurate with severe liver disease. Technofluor FXIII Activity is a rapid, accurate and precise assay suitable for routine diagnostic use with fewer interferents than ammonia release FXIII activity assays