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Three sets of activated carbons (ACs) were prepared with the same precursor but activated differently (by CO or water vapour) with various burn-off levels. The ACs demonstrate increased deviation of the pore shape from the slitshaped model with increasing burn-off and contributions of pores of different sizes depending on the activation type. Significant re-arrangement of adsorption complexes, especially of the Van der Waals type characteristic for nonpolar or weakly polar adsorbates (H, CH, CHCl, CHCl), occurs in both micropores and mesopores of ACs with decreasing temperature. The behaviour of their mixtures with water and DMSO can strongly differ from that of individual adsorbates. [ABSTRACT FROM AUTHOR]

We report on an approach toward the development of a high-resolution single photon emission computed tomography (SPECT) system to image the biodistribution of radiolabeled tracers such as Tc-99m and I-125 in unrestrained/unanesthetized mice. An infrared (IR)-based position tracking apparatus has been developed and integrated into a SPECT gantry. The tracking system is designed to measure the spatial position of a mouse's head at a rate of 10-15 frames per second with submillimeter accuracy. The high-resolution, gamma imaging detectors are based on pixellated NaI(Tl) crystal scintilator arrays, position-sensitive photomultiplier tubes, and novel readout circuitry requiring fewer analog-digital converter (ADC) channels while retaining high spatial resolution. Two SPECT gamma camera detector heads based upon position-sensitive photomultipiler tubes have been built and installed onto the gantry. The IR landmark-based pose measurement and tracking system is under development to provide animal position data during a SPECT scan. The animal position and orientation data acquired by the tracking system will be used for motion correction during the tomographic image reconstruction. [ABSTRACT FROM AUTHOR]

Context: Little is known about pregnancy outcomes among the approximately 11 million refugees worldwide, 25% of whom are women of reproductive age.Objective: To estimate incidence of and determine risk factors for poor pregnancy outcomes and to calculate the contribution of mortality from neonatal and maternal deaths to overall mortality in a refugee camp.Design: Cross-sectional review of records and survey, conducted in February and March 1998.Setting: Mtendeli refugee camp, Tanzania.Participants: For the overall assessment, 664 Burundi women who had a pregnancy outcome during a recent 5-month period (September 1, 1997-January 31, 1998) and their 679 infants; 538 women (81%) completed the survey.Main Outcome Measures: Incidence of fetal death (fetus born > or =500 g or > or =22 weeks' gestation with no signs of life), low birth weight (<2500 g), neonatal death (death <28 days of life), and maternal death (deaths during or within 42 days of pregnancy from any cause related to or aggravated by the pregnancy or its management).Results: The fetal death rate was 45.6 per 1000 births, the neonatal mortality rate was 29.3 per 1000 live births, and 22.4% of all live births were low birth weight. Compared with women without poor pregnancy outcome, those with poor pregnancy outcome were more likely to report prior high socioeconomic status (adjusted odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.4), having a first or second pregnancy (OR, 2.2; 95% CI, 1.4-3.4), and having 3 or more episodes of malaria during pregnancy (OR, 2.0; 95% CI, 1.4-3.1). Neonatal and maternal deaths accounted for 16% of all deaths during the period studied.Conclusions: Poor pregnancy outcomes were common in this refugee setting, and neonatal and maternal deaths, 2 important components of reproductive health-related deaths, contributed substantially to overall mortality. [ABSTRACT FROM AUTHOR]

Objective: Our purpose was to determine whether length of hospital stay after vaginal delivery as determined by the discharging physician is associated with rehospitalizations or increased outpatient contacts by mothers and neonates and to assess the impact of home health care visits.Study Design: An inception cohort study of all rehospitalizations and outpatient contacts of mothers and neonates after vaginal delivery at St. Joseph Hospital, Denver, Colorado, was done from January 1, 1994, to September 30, 1995. All Kaiser Permanente mother-neonate pairs in which the delivery was vaginal (excluding those with multiple gestations or birth weight < 2500 g) were included. Length of initial hospital stay was divided into three time periods: < or = 24 hours, 25 to 48 hours, and > 48 hours. The Colorado Kaiser Permanente Perinatal Database was used to identify perinatal and demographic factors that might have increased health care use. Additional information was sought in administrative databases, bill records, and inpatient charts. Mothers were followed up for 6 weeks and neonates for 28 days after delivery. Home care visits were provided to more than half the mothers and neonates by means of a standardized protocol. The main outcome measures were rehospitalizations and outpatient visits for mothers and neonate, controlling for home care visits.Results: A total of 4323 mother-neonate pairs were identified. For the mothers, a longer initial hospital stay (> 48 hours) was significantly associated with both readmission (P < .01) and increased outpatient care use (P = .01) in the 6-week postpartum period. Thirty-five mothers (.81%) were rehospitalized by 6 weeks. Maternal factors associated with increased outpatient contacts were preeclampsia, preterm delivery, and instrument delivery. Sixty-seven neonates (1.55%) were readmitted to the hospital. Home care visits reduced the need for both readmissions and outpatient visits.Conclusions: For mothers in this cohort a longer initial hospital stay was significantly associated with hospital readmission and increased outpatient care in the postpartum period. Further analysis revealed that mothers with recognized potential and observed problems were rarely discharged in < or = 24 hours. We did not find statistically significant problems among neonates that were related to the length of their initial hospital stay. Those neonates receiving home care were less likely to require hospital readmission and less likely to seek outpatient care. It is unlikely that a single discharge policy will be appropriate for all mothers and neonates. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the feasibility of evaluating the pharmacokinetics of radiolabeled anti-cancer drugs using spectral analysis, a non-compartmental tracer kinetic modeling technique, and positron emission tomography (PET).Methods: Dynamic PET studies were performed on patients receiving tracer doses of 5-fluorouracil (5-[18F]-FU) and two developmental drugs [11C]-temozolomide and [11C]-acridine carboxamide. Spectral analysis was then used to (a) determine individual and group average pharmacokinetics, (b) predict tumour handling in response to different drug administration regimens, and (c) produce functional parametric images describing regional pharmacokinetics.Results: Spectral analysis could distinguish tumour kinetics from normal tissue kinetics in an individual [11C]-temozolomide study and demonstrated a markedly greater volume of distribution (VD) in glioma than in normal brain, although there was no appreciable difference in mean residence time. Analysis of pooled acridine carboxamide data (n = 22) revealed a relatively large VD (and prolonged retention) in the liver and spleen and a markedly lower VD (and initial uptake) in the brain. Continuous infusion of 5-[18F]-FU was predicted to achieve a concentration in colorectal metastases in liver approximately 10 times that achieved in plasma at 10 h after commencement of the infusion.Conclusions: We conclude that spectral analysis provides important pharmacokinetic information about radiolabeled anti-cancer drugs with relatively few model assumptions. [ABSTRACT FROM AUTHOR]

Women in later stages of pregnancy are at increased risk for serious influenza-related morbidity; thus, universal influenza vaccination of pregnant women is recommended. However, vaccine uptake in the United States has been suboptimal. We previously described the burden of severe influenza-related morbidity during pregnancy in the United States by examining hospitalizations of pregnant women with respiratory illness during influenza season. Nondelivery hospitalizations with respiratory illness had significantly longer lengths of stay than those without respiratory illness. Hospitalization characteristics associated with greater likelihood of respiratory illness were the presence of a high-risk condition for which influenza vaccination is recommended, Medicaid/Medicare as primary expected payer, and hospitalization in a rural area. These findings may be explained by these women being at higher risk of influenza-related morbidity or reflect disparities in receipt of influenza immunization. Universal vaccination of pregnant women to decrease influenza-related morbidity should be encouraged. [ABSTRACT FROM AUTHOR]