bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automotive, Molded Viscoelastic Foams
Authors: Farkas Paul , Stanciu Romeo , Mendoza Liberato 
Published: April 2004

An improved type ofmolded viscoelastic foam, Intellisense TM(Trademark of Woodbridge Foam Corporation), extends the effective operating range ofthe material from elevated temperatures to below 0 C, while maintaining the energy dissipation values at designed levels. Until now, viscoelastic (VE) foams have not found a significant success in automotive interior/exterior applications due to an evident loss ofsome essential properties with changing conditions (e.g. diminished softness/ “friendliness” in contact with human body when used at low temperatures or reduced VE properties at high temperatures). A viscoelastic behavior means a time-delayed and rate-dependent response to applied stress [Birley, A.W. et al. (1991). Physics of Plastics, pp. 260–261, Oxford University Press, New York, NY] and makes it desirable in parts designed for specific energy management (EM). However, to be acceptable for an application, the effectiveness of the foam response has to be in the expected usage temperature range of the final part. Systems formulated with a balanced mixture ofpolyols, some special additives, and modified isocyanates generated VE foams with the glass transition temperature (Tg) below 20 C. The observed loss ofviscoelasticity at elevated temperatures, common with prior-art foam of this type, is significantly reduced as well. This novel approach to viscoelastic foams will benefit energy management automotive applications like head restraint, seat occupant safety, sound or vibration attenuation, etc. It is expected that this finding may extend the area of applicability beyond the car industry.
An Evaluation of the Thermal Conductivity of Extruded Polystyrene Foam Blown with HFC-134a or HCFC-142b
Authors: Vo Chau V. , Paquet Andrew N. 
Published: April 2004

Insulation performance of extruded polystyrene (XPS) foams expanded with various halogenated blowing agents including HFC-134a or HCFC-142b was measured over time. Residual blowing agents were measured after aging up to 26 years. The diffusive transport properties of the blowing agents can be determined through the mathematical calculation of the heat transfer in the gas phase component of the foam thermal conductivity. These values are used in a Dow model which allows an accurate prediction of the long-term thermal resistance of extruded polystyrene foams blown with a variety of blowing agents including CFC-12, HCFC-142b, HCFC-22, HFC-134a, HFC-152a, and CO2. Excellent agreement was obtained between measured and predicted thermal conductivity values with samples stored in laboratory conditions, as well as samples extracted from field conditions, such as cellar and upside-down roof applications. The results confirm the slow diffusion rate of CFC-12, HCFC-142b and HFC-134a through extruded polystyrene foam, and demonstrate that HFC-134a or HCFC-142b-blown extruded polystyrene (XPS) foams meet the requirement for applications requiring excellent long-term insulation performance. HCFC-22 and HFC-152a are fugitive blowing agents in XPS foams, and the thermal performance of foams made with these blowing agents reach the thermal performance of CO2-blown foams after a short aging period.
Mechano-Chemical Reclamationof Waste Rubber Powder andIts Effect on the performanceof NR and SBR Vulcanizates
Authors: Yehia A. A. , Ismail M. N. , Hefny Y. A. , Abdel-Bary E. M. , Mull M. A. 
Published: April 2004

Waste rubber powder (RP) was processed in a Brabenderpremixer under various conditions in the presence of reclaiming agents toconvert the RP into plastic mass (reclaimed rubber), then the obtained reclaimwas blended with both NR and SBR in different ratios. It was found that thebehavior of the reclaim in both NR and SBR is the same. The rheometriccharacteristics show that by increasing the reclaim ratio, the curing time wasdecreased and consequently the cure rate index was increased. Also themaximum torque of the same rubber compounds was decreased. The physico-mechanical data of the reclaim/NR and reclaim/SBR blends showthat the tensile strength as well as elongation at break were decreased withincreasing the reclaim ratio in the blend. On the other hand the equilibrium swellingwas increased. However one can replace about 10–30% of NR or SBR by thereclaim without sacrificing the essential characteristics of the rubber vulcanizates.
Optimal Allocation of Resources across Four Interventions for Type 2 Diabetes
Authors: Earnshaw Stephanie R. , Richter Anke , Sorensen Stephen W. , Hoerger Thomas J. , Hicks Katherine A. , Engelgau Michael , Thompson Ted , Venkat Narayan K. M. , Williamson David F. , Gregg Edward , Zhang Ping 
Published: April 2004

Background Several interventions can be applied to prevent complications of type 2 diabetes. This article examines the optimal allocation of resources across 4 interventions to treat patients newly diagnosed with type 2 diabetes. The interventions are intensive glycemic control, intensified hypertension control, cholesterol reduction, and smoking cessation. Methods A linear programming model was designed to select sets of interventions to maximize quality-adjusted life years (QALYs), subject to varied budget and equity constraints. Results For no additional cost, approximately 211,000 QALYs can be gained over the lifetimes of all persons newly diagnosed with diabetes by implementing interventions rather than standard care. With increased availability of funds, additional health benefits can be gained but with diminishing marginal returns. The impact of equity constraints is extensive compared to the solution with the same intervention costs and no equity constraint. Under the conditions modeled, intensified hypertension control and smoking cessation interventions were provided most often, and intensive glycemic control and cholesterol reduction interventions were provided less often. Conclusions A resource allocation model identifies trade-offs involved when imposing budget and equity constraints on care for individuals with newly diagnosed diabetes.
Cost-Effectiveness of the Pneumococcal Vaccine in Healthy Younger Adults
Authors: Vold Pepper Patricia , Owens Douglas K. 
Published: April 2004

Objectives Routine vaccination for Streptococcus pneumoniae has been recommended as a cost-effective measure for elderly and immunocompromised patients, yet no analysis has been performed for healthy younger adults in America. The authors evaluated the cost-effectiveness of the pneumococcal vaccine and determined the net health benefits conferred for the healthy young adult population. Methods The authors developed a decision model to compare the health and economic outcomes of vaccinate versus do not vaccinate for S. pneumoniae. Results Vaccinating patients for S. pneumoniae generates benefits that are dependent on incidence rates and the efficacy of the vaccine. In the 22-year-old patient with a pneumonia incidence of 0.3/1000, the vaccine would need to be >71 percent effective for the vaccination strategy to cost less than $50,000/QALY gained. At an incidence of 0.4/1000, the threshold efficacy is 53 percent, whereas at 0.5/1000 it is 43 percent. In the 35-year-old patient where the incidence of pneumococcal pneumonia is higher (0.85/1000), the vaccine would be cost-effective with an efficacy as low as 30 percent. Conclusions Use of the S. pneumoniae vaccine in young adults would provide modest reductions in pneumonia-associated morbidity and mortality. Vaccination of young adults is moderately expensive unless vaccine efficacy is above 50% to 60%. In 35-year-old adults, use of the vaccine is cost-effective even with moderate efficacy.
The Impact of Expected HIV Transmission Rates on the Effectiveness and Cost of Ruling Out HIV Infection in Infants
Authors: Mrus Joseph M. , Yi Michael S. , Eckman Mark H. , Tsevat Joel 
Published: April 2004

Objective To quantify the costs and effectiveness of different strategies for ruling out HIV infection in infants born to HIV-infected mothers in the United States. Methods The authors assessed 4 different testing strategies that incorporated serial HIV DNA polymerase chain reaction (PCR) testing with or without enzyme-linked immunosorbent assay (ELISA) antibody testing. Testing costs, false reassurance rates, and incremental cost-effectiveness ratios were compared for the 4 strategies. Results In HIV-exposed infants, HIV DNA PCR testing at birth, 1 month, and 4 months of age results in a false reassurance rate of 21 per million (at a 2% transmission rate). Adding an ELISA test lowers the false reassurance rate to 0.052 per million at a cost of $570,000 per additional case detected; adding another PCR lowers the false reassurance rate to 1.49 per million at a cost of $720,000 per additional case detected compared with the 3-PCR strategy. At a high transmission rate (20%), there would be substantially more erroneously negative results (false reassurance rate is 256 per million with PCR testing at birth, 1 month, and 4 months) and consequently more favorable cost-effectiveness ratios with additional testing: $47,000 per additional case detected by adding 1 ELISA test and $59,000 per additional case detected by adding an other PCR test. Conclusions False-negative HIV results after serial testing in exposed infants are rare, and the incremental cost-effectiveness ratios of additional tests are substantial at low transmission rates. However, the false reassurance rate increases considerably with a 3-PCR strategy and additional testing becomes more cost-effective at greater transmission rates; therefore, additional testing may be warranted in infants at greater risk of infection.
Cost-Benefit Analysis of a New HEDIS Performance Measure for Pneumococcal Vaccination
Authors: Ahmed Faruque , Elbasha Elamin E. , Thompson Betsy L. , Harris Jeffrey R. , Sneller Vishnu-Priya 
Published: April 2004

Objectives Measurement of the quality of care provided by managed care organizations (MCOs) has achieved national prominence, though there is controversy regarding its value. This article assesses the economic implications of a new Health Plan Employer Data and Information Set (HEDIS®) measure for pneumococcal vaccination. Methods A Markov decision model, with Monte Carlo simulations, was utilized to conduct a cost-benefit analysis of annual HEDIS-associated interventions, which were repeated for 5 consecutive years, in an average Medicare MCO, using a societal perspective and a 3% annual discount rate. Results Compared with the status quo, the HEDIS intervention will be cost saving 99.8% of the time, with an average net savings of $3.80 per enrollee (95% probability interval: $0.73–$6.87). Conclusions The new HEDIS measure will save societal dollars. This type of analysis is essential if performance measurement is to become a legitimate part of our health care landscape.
Assessing Preferences for Prevention versus Treatment Using Willingness to Pay
Authors: Corso Phaedra S. , Hammitt James K. , Graham John D. , Dicker Richard C. , Goldie Sue J. 
Published: April 2004

Background Rising health care costs and limited resources necessitate trade-offs between resources allocated toward prevention and those toward treatment. Information from opinion polls suggests citizens favor spending a higher proportion of all health care dollars on prevention rather than treatment. Objectives To assess the policy implications of willingness to pay (WTP) for use in cost-benefit analysis (CBA) as a method for capturing individual preferences for prevention and treatment in the context of resource allocation decisions. Methods The authors recruited a random sample of 1456 US residents age 18 years and greater by telephone using random-digit dialing. The survey was designed as a 3-stage (phone-mail-phone) process and was conducted between December 1998 and March 1999. For all persons completing the survey (N = 1104), the authors 1st collected respondents’ opinions about the costs and effectiveness of prevention versus treatment programs in general. Half of respondents were then asked to state their WTP for a hypothetical prevention scenario and half were asked to state their WTP for a hypothetical treatment scenario. Both scenarios were specific to the same health context and included an identical reduction in mortality risk. Results WTP for treatment was significantly greater than WTP for prevention, $665 and $223, respectively. Prior opinions on the relative effectiveness afforded by preventive and treatment interventions moderately influenced the WTP estimates for persons randomized to either scenario. Prior opinions on costs had no significant effect on WTP estimates for either scenario. WTP significantly increased with age and household income in the full sample but was not significantly affected by gender or educational attainment. Conclusions The aggregated WTP responses from the prevention and treatment scenarios presented in our study would imply that treatment is more strongly preferred by society than prevention when the health context is the same and benefits of each are held constant. A better understanding is needed of the discrepancy between citizens’ stated preferences for prevention (e.g., through polling) and our findings that they were willing to pay substantially more for treatment than for prevention.
A Further Development in Social Marketing
Authors: Binney Wayne , Hall John , Shaw Mike 
Published: April 2004

This social marketing study discusses the application of Rothschild’s MOA framework (Motivation, Opportunity, and Ability) in a land-use management context. The authors hypothesize that landholders with higher levels of MOA are positively associated with behavior that would result in the effective control of a vertebrate pest (the European rabbit). A random sample of 566 land managers in southeastern Australia was obtained. The development of scales associated with this study were the result of intensive qualitative research, including focus groups, in-depth interviews, and a thorough review of secondary resources. The scales were developed through a factor analytic process and were piloted and pre-tested before being used. From the study it is ascertained that about one-third of land managers fall into the highest level of effective behavior, and for the remainder, social marketing interventions, using marketing, education, and the law, could be applied to changebehavior. The study provides evidence that Rothschild’s theoretical MOA framework can be applied to a social market and thus provides guidance on the types of interventions that may be effective in altering behavior. The MOA framework also provides a mechanism for segmentation that can be used to describe various markets and gives direction to the interventions that may be effective in altering behavior.
A Comparison of Three Dementia Screening Instruments Administered by Telephone in China
Authors: Zhou Jingsheng , Zhang Xinqing , Mundt James C. , Wang Lidong , Meng Chao , Chu Changbiao , Yang Jing , Chan Piao 
Published: April 2004

Implementation of valid and efficient case-finding methods to screen for cognitive impairment is important for identifying people during the earliest stages of dementia. The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), Information-Memory-Concentration Test (IMCT), and Blessed-Roth Dementia Scale (BRDS) are assessment tools commonly used in China. This study investigated the usefulness of administering these scales by telephone. Subjects ( N= 132: 74 females, 58 males) from Xuanwu Hospital, Capital University of Medical Sciences in Beijing, China were recruited for participation in this study; 132 collateral informants who accompanied the subjects to their appointments provided IQCODE and BRDS data. Senior neurologists using Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria (American Psychiatric Publishing, 2000), patient history, physical examination, neuropsychological tests, neuroradiology, and laboratory tests made the dementia diagnoses. Blinded personnel administered the IQCODE, IMCT, and BRDS by telephone and face-to-face in the clinic in counter-balanced administration order. Independent subsamples of 20 subjects were selected for assessment of test-retest and inter-rater reliabilities of the telephone assessments. Correlations between the face-to-face and telephone administrations of the scales were good, ranging from .80 to .97. The administration order of assessment methods did not affect the results. Inter-rater and test-retest reliabilities were satisfactory. The sensitivity and specificity of each scale exceeded 80 percent, demonstrating scale validity and clinical utility. The results support reliable and valid administration of these dementia assessments in person or over the telephone. The appropriate selection of assessment instruments is dependent upon the characteristics of the patient population and the intended use of the results. Use of telephone assessments may provide a valid and efficient method to screen elderly people for early detection of dementia symptoms and to monitor the effectiveness of treatment.
Variables that Affect/Control High-Density Polyethylene Film Oxygen-Moisture Barrier
Authors: Todd William G. 
Published: April 2004

Multiple layer polyolefin-based films continue to be one of the preferred packages for both the food and medical industries. The technology of these films has advanced over the years from simple monolayer structures to multilayer hybrid structures. These affordable packages not only provide tamper proof evidence, but also protection from insects, bacteria, germs, and dust and are very effective in providing moisture and oxygen barrier. This paper will discuss these latter two properties, moisture and oxygen barrier, when polyethylene is used as the primary film component. Many variables affect high-density polyethylene (HDPE) film’s oxygen transmission rates (OTR), and water vapor transmission rates (WVTR). These variables include film crystalline structure, relaxation rates of molten polyethylene, polyethylene manufacturing technology, polyethylene resin physical properties, atmospheric conditions, and film fabrication technology and structure. This paper will describe how permeation rates are measured and how each of the above variables affects the permeation rates.
Neptunium incorporation into uranyl compounds that form as alteration products of spent nuclear fuel: Implications for geologic repository performance
Authors: Burns Peter C. , Deely Kathryn M. , Skanthakumar Suntharalingam 
Published: April 2004

SummaryAlteration of spent nuclear fuel in a geological repository under oxidizing conditions is likely to result in abundant uranyl compounds. Incorporation of radionuclides into the uranyl alteration phases may significantly reduce their mobility, thereby impacting repository performance. The following compounds have been synthesized from solutions containing from ∼10 to 500ppm Np5+: meta-schoepite, UO3·2H2O; Na-compreignacite, Na2[(UO2)3O2(OH)3]2(H2O)7; uranophane, Ca(UO2)2(SiO3OH)2(H2O)5; and β-(UO2)(OH)2. The structures of each involve sheets of uranyl polyhedra; the interlayers contain cations and H2O groups in Na-compreignacite and uranophane, only H2O in meta-schoepite, and β-(UO2)(OH)2does not contain interlayer constituents. Synthesized powders were characterized by X-ray powder diffractometry, and were analyzed by ICP-AES (U, Na, Ca) and ICP-MS (Np). Aliquots of the powders were washed in 0.5M acetic acid to remove sorbed Np prior to analysis. The powders of meta-schoepite and β-(UO2)(OH)2contained at most a few ppm Np5+. In contrast, powders of Na-compreignacite and uranophane contained Np5+in proportion to the Np5+concentration in the mother solution, and powders of each containing more than 400ppm Np5+(of total Np + U) were obtained. Incorporation of Np5+into uranyl compounds that form in a geological repository appears possible, and may impact the mobility of Np.
Enhanced production possibility of the therapeutic radionuclides 64Cu, 67Cu and 89Sr via (n,p) reactions induced by fast spectral neutrons
Authors: Spahn I. , Coenen Heinz H. , Qaim Syed M. 
Published: April 2004

Summary
Spectrum averaged cross sections for the 64Zn(n,p)64Cu, 67Zn(n,p)67Cu and 89Y(n,p)89Sr reactions were measured using a 14MeV d(Be) neutron source. In each case a clean radiochemical separation was performed and the radioactivity of the product was determined via high-resolution γ-ray spectrometry or anticoincidence β
- counting. The cross sections are three to five times higher than with a fission neutron spectrum. It is postulated that at an intense fast spectral neutron source, e.g. a spallation source, it would be advantageous to use an (n,p) reaction: GBq amounts of 64Cu and 67Cu could be produced in one hour irradiation and of 89Sr in about one day irradiation.
Thrombocytopenia due to acute venous thromboembolism and its role in expanding the differential diagnosis of heparin‐induced thrombocytopenia
Authors: Kitchens Craig S. 
Published: April 2004

AbstractThrombocytopenia is an uncommon but serious consequence of heparin administration. Occasionally patients with massive acute venous thromboembolism (VTE) will develop thrombocytopenia. As heparin or some thrombin inhibitor is strongly indicated in acute VTE, it is important to distinguish this event from heparin‐induced thrombocytopenia (HIT). Four patients are presented who developed thrombocytopenia so early in their course of VTE and/or therapy with heparin that HIT was considered unlikely. The mean nadir platelet count for these four patients was 60,000/μl occurring at a mean time of 18 hr after the initiation of heparin therapy. Because of strong indications to continue heparin for their acute VTE in the face of a very low likelihood that they did have HIT, heparin was continued with excellent results and resolution of the thrombocytopenia. The literature of this subject is reviewed. Thrombocytopenia following VTE is actually rather common, but it is usually milder than in these four cases. In some cases such as these four, the thrombocytopenia can be sudden and rather severe causing diagnostic confusion with HIT. Am. J. Hematol. 76:69–73, 2004. © 2004 Wiley‐Liss, Inc.
Differences in the frequency of the C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene among the Lebanese population
Authors: Almawi Wassim Y. , Finan Ramzi R. , Tamim Hala , Daccache Jocelyn L. , Irani‐Hakime Noha 
Published: April 2004

AbstractIn view of its role in precipitating mild hyperhomocysteinemia as well as being a risk factor for vascular thrombosis, we investigated the frequency of the C677T mutation of the methylenetetrahydrofolate reductase (MTHFR) gene among 589 healthy Lebanese subjects by PCR‐RFLP analysis (HinfI digestion) and compared them with those of other countries of Caucasian and non‐Caucasian origin. The prevalence of the mutated homozygous (T/T) and heterozygous (C/T) C677T MTHFR genotype was 11.04% and 39.73%, respectively, giving an allele frequency of 0.309. While the prevalence of the T/T genotype was similar with respect to gender, higher prevalence was noted among Christian (13.08%) compared to Moslem (7.66%) subjects (P < 0.001), and heterogeneity in its distribution was seen in the different Lebanese provinces, and was directly related to the Christian/Moslem composition of each province. The distribution of the MTHFR C677T in Lebanon is unique with regard to its higher occurrence among Christians compared to Moslems, adding to the existing body of literature on the heterogeneity of its prevalence and distribution. Am. J. Hematol. 76:85–87, 2004. © 2004 Wiley‐Liss, Inc.