Sociodemographic factors and the variation in syphilis rates among US counties, 1984 through 1993: an ecological analysis

OBJECTIVES: Syphilis in the United States is focally distributed, with high incidence rates in the South and in metropolitan areas nationwide. In this study an ecological analysis, using the county as the unit of analysis, was performed to generate hypotheses about community-level determinants of syphilis rates. METHODS: Bivariate rank correlations and multivariate, backward stepwise elimination linear regressions were performed. Mean annual incidence of primary- and secondary-stage syphilis in a county was the dependent variable, and county sociodemographic characteristics (from census data) were the independent variables. RESULTS: In the multivariate regression model, sociodemographic characteristics accounted for 71% of the variation in syphilis rates among counties. With other factors accounted for, the most highly correlated characteristics were percentage non-Hispanic Black population, county location in the South, percentage of the population that was urban, percentage Hispanic population, and percentage of births to women younger than 20 years. CONCLUSIONS: Most of the variation in syphilis rates among counties is accounted for by sociodemographic characteristics. Identification and remediation of modifiable health determinants for which these factors are markers are needed to improve the health status of these populations.     

On the Refinement Mechanism of Silicon in Al-Si-Cu-Zn Alloy with Addition of Bismuth

Obtained results of micro and nano studies reveal that bismuth refines the silicon in which the flake silicon changed to lamellar structure with reduction in twin spacing from 160 to 75 nm. Bismuth segregates towards the inter-dendritic regions and decreases the Al-Si contact angle resulting in suppression of the silicon growth causing refinement of the eutectic structure. Increased recalescence temperature and time confirmed that the refinement effect is attributed to the growth stage.     

Human immunodeficiency virus partner notification. Cost and effectiveness data from an attempted randomized controlled trial

OBJECTIVE: Determine the cost and effectiveness of partner notification for human immunodeficiency virus (HIV) infection. METHODS: Persons testing HIV positive in three areas were randomly assigned one of four approaches to partner notification. Analysis plans changed because disease intervention specialists notified many partners from the patient referral group. We dropped the patient referral group and combined the others to assess the cost and effectiveness of provider referral. RESULTS: The 1,070 patients reported 8,633 partners. Of those 1,035 were located via record search or in person. A previous positive test was reported by 248 partners. Of the 787 others, 560 were tested: 438 were HIV negative and 122 were newly identified as HIV positive. The intervention specialist's time totaled 197 minutes per index patient. The cost of the intervention specialist's time, travel, and overhead was $268,425: $251 per index patient, $427 per partner notified, or $2,200 per new HIV infection identified. No demographic characteristic of the index patient strongly predicted the likelihood of finding an infected partner. CONCLUSION: We could not compare the effectiveness of different partner notification approaches because of frequent crossover between randomized groups. The cost of partner notification can be compared with other approaches to acquired immunodeficiency syndrome prevention, but the benefits are not easily measured. We do not know the number of HIV cases prevented or the value of fulfilling the ethical obligation to warn partners of a potential threat to their health.     

Voltage sensitivity of the osteoclast calcium receptor

We demonstrated previously that osteoclasts possess a divalent cation-sensitive "receptor", the Ca2+ receptor. Activation of the Ca2+ receptor by the surrogate cation Ni2+ was shown to elicit an increase in cytosolic [Ca2+] to a peak value followed by an exponential decline. In the present study we examined the influence of surface membrane voltage on the kinetics of Ca2+ receptor inactivation. The K+ ionophore, valinomycin was applied to intercept the declining phase of the cytosolic [Ca2+] transient elicited by application of between 50 microM- and 5 mM-[Ni2+]. This resulted in a sustained elevation of cytosolic [Ca2+] or even a 'hump' followed by a gradual decline. Such a kinetic alteration persisted in a Ca(2+)-free solution, but was abolished in high extracellular [K+] (105 mM). Thus, we demonstrate for the first time to our knowledge, a modulatory effect of membrane potential on the function of the osteoclast Ca2+ receptor.     

The influence of safety belt laws on self- reported safety belt use in the United States

We assessed rates and trends in safety belt use by presence and type of safety belt law using data from states participating in the 1984–1989 Behavioral Risk Factor Surveillance System. State(s) with a safety belt law allowing law enforcement officers to stop vehicles for occupants' failure to use safety belts (primary enforcement law) had greater and more rapid increases in safety belt use rates than did states with laws requiring that vehicles must first be stopped for some other violation before a citation or fine for occupants' failure to use safety belts could be imposed (secondary enforcement law). Larger and sustained increases in safety belt use occurred when safety belt laws became effective or when fines were imposed for violations than when laws were first enacted. These data suggest that primary enforcement laws result in greater and more rapid increases in safety belt use than do secondary enforcement laws, and that initial increases in safety belt use following implementation of laws are sustained.     

Orthotopic heart transplantation in a transgenic pig-to-primate model

BACKGROUND: Previous studies demonstrated that hearts from transgenic pigs expressing human decay-accelerating factor (hDAF) were not hyperacutely rejected when transplanted heterotopically into the abdomen of cynomolgus monkeys. This study examines orthotopic transplantation of hDAF transgenic pig hearts into baboon recipients. METHODS: Orthotopic xenogeneic heart transplantation was performed using piglets, transgenic for hDAF, as donors. Ten baboons were used as recipients and were immunosuppressed with a combination of cyclophosphamide, cyclosporine, and steroids. RESULTS: Five grafts failed within 18 hr without any histological signs of hyperacute rejection. Pulmonary artery thrombosis induced by a size mismatch was observed in two of these animals. The other three recipients died because of failure to produce even a low cardiac output and/or dysrhythmia. The remaining five animals survived between four and nine days. One animal died of bronchopneumonia on day 4. Three xenografts stopped beating on day 5 due to acute vascular rejection. The longest survivor was killed on day 9 with a beating, histologically normal xenograft, because of pancytopenia. CONCLUSIONS: The results reported here demonstrate that hDAF transgenic pig hearts are not hyperacutely rejected when transplanted into baboon recipients. Orthotopically transplanted transgenic pig hearts are capable of maintaining cardiac output in baboons. An optimum immunosuppressive regimen is the subject of ongoing research.     

The use of a multipurpose stent in children

OBJECTIVES: To assess the use of a multipurpose stent (the 'Blue stent', Angiomed Urosoft Pyeloplasty Stent, Bard, UK) in children undergoing pyeloplasty and ureteric reimplantation. PATIENTS AND METHODS: Between August 1994 and August 1996, the Blue stent was used in 50 renal units in 46 children aged 2 months to 12 years and 6 months. Twenty-five children underwent pyeloplasty, 11 had ureteric reimplantation for vesico-ureteric reflux (VUR), eight had ureteric reimplantation with remodelling for obstructed megaureters and in two patients it was used during the removal of stones. The mean follow-up was 18 months (range 6-30 months). RESULTS: After pyeloplasty, 22 patients (88%) had improved renal function and drainage with a decrease in hydronephrosis; two patients had a decrease in hydronephrosis only, one had an anastomotic leak and needed a repeat pyeloplasty and four developed a urinary tract infection (UTI). After ureteric reimplantation, VUR was not detected in any patient. Two patients had no change in drainage after remodelling and reimplantation of a megaureter, one was later diagnosed as having a neuropathic bladder and one child developed a UTI after ureteric reimplantation. The hospital stay was 3 days after pyeloplasty and 5 days after reimplantation. CONCLUSION: The design of the multipurpose Blue stent provides versatility; it can be used as a stent, and both an internal and external drain. Its use does not prolong the hospital stay. Insertion causes minimal trauma to the renal parenchyma, and removal is easy, pain-free and requires no anaesthesia. The complication rates in the present series compare favourably with other reported series.     

Circulation rates of boiling liquids in a vertical tube

An experimental study of heat transfer to boiling liquids under natural convective flow has been carried out in a single tube vertical thermosiphon reboiler to investigate the effect of heat flux and submergence on circulation rates. The test liquids used were distilled water, various concentrations of propan-2-ol in water and their azeotrope. The test section was an electrically heated stainless steel tube of 25.56 mm i.d., 28.85 mm o.d. and 1900 mm long with twenty-one spot welded copper constantan thermocouples to measure the variations in wall temperature along its axis. The uniform heat fluxes in the range of 3.5–42.4 kW/m² were employed while inlet liquid sub-cooling varied from 0.2 to 30.7 °C. The liquid submergence levels were maintained in the range 30–100%. The typical experimental data has been graphically presented and discussed. An empirical correlation has been developed from the experimental data of the present study through regression analysis.     

Emotional speaker recognition in real life conditions using multiple descriptors and i-vector speaker modeling technique

Multimedia Tools and Applications - Emotional speaker recognition under real life conditions becomes an urgent need for several applications. This paper proposes a novel approach using multiple...