Ion thrusters for electric propulsion: Scientific issues developing a niche technology into a game changer.

The transition from old space to new space along with increasing commercialization has a major impact on space flight, in general, and on electric propulsion (EP) by ion thrusters, in particular. Ion thrusters are nowadays used as primary propulsion systems in space. This article describes how these changes related to new space affect various aspects that are important for the development of EP systems. Starting with a historical overview of the development of space flight and of the technology of EP systems, a number of important missions with EP and the underlying technologies are presented. The focus of our discussion is the technology of the radio frequency ion thruster as a prominent member of the gridded ion engine family. Based on this discussion, we give an overview of important research topics such as the search for alternative propellants, the development of reliable neutralizer concepts based on novel insert materials, as well as promising neutralizer-free propulsion concepts. In addition, aspects of thruster modeling and requirements for test facilities are discussed. Furthermore, we address aspects of space electronics with regard to the development of highly efficient electronic components as well as aspects of electromagnetic compatibility and radiation hardness. This article concludes with a presentation of the interaction of EP systems with the spacecraft.

Impact of physical exercise on sensor performance of the FreeStyle Libre intermittently viewed continuous glucose monitoring system in people with Type 1 diabetes: a randomized crossover trial.

AIMS: To evaluate the sensor performance of the FreeStyle Libre intermittently viewed continuous glucose monitoring system using reference blood glucose levels during moderate-intensity exercise while on either full or reduced basal insulin dose in people with Type 1 diabetes. METHODS: Ten participants with Type 1 diabetes [four women, mean ± sd age 31.4 ± 9.0 years, BMI 25.5±3.8 kg/m2 , HbA1c 55±7 mmol/mol (7.2±0.6%)] exercised on a cycle ergometer for 55 min at a moderate intensity for 5 consecutive days at the clinical research facility, while receiving either their usual or a 75% basal insulin dose. After a 4-week washout period, participants performed the second exercise period having switched to the alternative basal insulin dose. During exercise, reference capillary blood glucose values were analysed using the fully enzymatic-amperometric method and compared with the interstitial glucose values obtained. Intermittently viewed continuous glucose monitoring accuracy was analysed according to median (interquartile range) absolute relative difference, and Clarke error grid and Bland-Altman analysis for overall glucose levels during exercise, stratified by glycaemic range and basal insulin dosing scheme (P<0.05). RESULTS: A total of 845 glucose values were available during exercise to evaluate intermittently viewed continuous glucose monitoring sensor performance. The median (interquartile range) absolute relative difference between the reference values and those obtained by the sensor across the glycaemic range overall was 22 (13.9-29.7)%, and was 36.3 (24.2-45.2)% during hypoglycaemia, 22.8 (14.6-30.6)% during euglycaemia and 15.4 (9-21)% during hyperglycaemia. Usual basal insulin dose was associated with a worse sensor performance during exercise compared with the reduced (75%) basal insulin dose [median (interquartile range) absolute relative difference: 23.7 (17.2-30.7)% vs 20.5 (12-28.1)%; P<0.001). CONCLUSIONS: The intermittently viewed continuous glucose monitoring sensor showed diminished accuracy during exercise. Absolute glucose readings derived from the sensor should be used cautiously and need confirmation by additional finger-prick blood glucose measurements.

Number and cost of hospitalizations with principal and secondary diagnoses of tuberculosis, United States.

OBJECTIVE: To estimate the number and cost of hospitalizations with a diagnosis of active tuberculosis (TB) disease in the United States. METHODS: We analyzed the 2014 National In-Patient Sample using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9) codes to identify hospitalizations with a principal (TB-PD) or any secondary discharge (TB-SD) TB diagnosis. We used a generalized linear model with log link and gamma distribution to estimate the cost per TB-PD and TB-SD episode adjusted for patient demographics, insurer, clinical elements, and hospital characteristics. RESULTS: We estimated 4985 TB-PD and 6080 TB-SD hospitalizations nationwide. TB-PD adjusted averaged $16 695 per episode (95%CI $16 168-$17 221). The average for miliary/disseminated TB ($22 498, 95%CI $21 067-$23 929) or TB of the central nervous system ($28 338, 95%CI $25 836-$30 840) was significantly greater than for pulmonary TB ($14 819, 95%CI $14 284-$15 354). The most common principal diagnoses for TB-SD were septicemia (n = 965 hospitalizations), human immunodeficiency virus infection (n = 610), pneumonia (n = 565), and chronic obstructive pulmonary disease and bronchiectasis (COPD-B, n = 150). The adjusted average cost per TB-SD episode was $15 909 (95%CI $15 337-$16 481), varying between $8687 (95%CI $8337-$9036) for COPD-B and $23 335 (95%CI $21 979-$24 690) for septicemia. TB-PD cost the US health care system $123.4 million (95%CI $106.3-$140.5) and TB-SD cost $141.9 million ($128.4-$155.5), of which Medicaid/Medicare covered respectively 67.2% and 69.7%. CONCLUSIONS: TB hospitalizations result in substantial costs within the US health care system.

Pushing the limits of in vivo diffusion MRI for the Human Connectome Project.

Perhaps more than any other "-omics" endeavor, the accuracy and level of detail obtained from mapping the major connection pathways in the living human brain with diffusion MRI depend on the capabilities of the imaging technology used. The current tools are remarkable; allowing the formation of an "image" of the water diffusion probability distribution in regions of complex crossing fibers at each of half a million voxels in the brain. Nonetheless our ability to map the connection pathways is limited by the image sensitivity and resolution, and also the contrast and resolution in encoding of the diffusion probability distribution. The goal of our Human Connectome Project (HCP) is to address these limiting factors by re-engineering the scanner from the ground up to optimize the high b-value, high angular resolution diffusion imaging needed for sensitive and accurate mapping of the brain's structural connections. Our efforts were directed based on the relative contributions of each scanner component. The gradient subsection was a major focus since gradient amplitude is central to determining the diffusion contrast, the amount of T2 signal loss, and the blurring of the water PDF over the course of the diffusion time. By implementing a novel 4-port drive geometry and optimizing size and linearity for the brain, we demonstrate a whole-body sized scanner with G(max) = 300 mT/m on each axis capable of the sustained duty cycle needed for diffusion imaging. The system is capable of slewing the gradient at a rate of 200 T/m/s as needed for the EPI image encoding. In order to enhance the efficiency of the diffusion sequence we implemented a FOV shifting approach to Simultaneous MultiSlice (SMS) EPI capable of unaliasing 3 slices excited simultaneously with a modest g-factor penalty allowing us to diffusion encode whole brain volumes with low TR and TE. Finally we combine the multi-slice approach with a compressive sampling reconstruction to sufficiently undersample q-space to achieve a DSI scan in less than 5 min. To augment this accelerated imaging approach we developed a 64-channel, tight-fitting brain array coil and show its performance benefit compared to a commercial 32-channel coil at all locations in the brain for these accelerated acquisitions. The technical challenges of developing the over-all system are discussed as well as results from SNR comparisons, ODF metrics and fiber tracking comparisons. The ultra-high gradients yielded substantial and immediate gains in the sensitivity through reduction of TE and improved signal detection and increased efficiency of the DSI or HARDI acquisition, accuracy and resolution of diffusion tractography, as defined by identification of known structure and fiber crossing.

Maternal obesity and risk of cesarean delivery: a meta-analysis.

Despite numerous studies reporting an increased risk of cesarean delivery among overweight or obese compared with normal weight women, the magnitude of the association remains uncertain. Therefore, we conducted a meta-analysis of the current literature to provide a quantitative estimate of this association. We identified studies from three sources: (i) a PubMed search of relevant articles published between January 1980 and September 2005; (ii) reference lists of publications selected from the search; and (iii) reference lists of review articles published between 2000 and 2005. We included cohort designed studies that reported obesity measures reflecting pregnancy body mass, had a normal weight comparison group, and presented data allowing a quantitative measurement of risk. We used a Bayesian random effects model to perform the meta-analysis and meta-regression. Thirty-three studies were included. The unadjusted odd ratios of a cesarean delivery were 1.46 [95% confidence interval (CI): 1.34-1.60], 2.05 (95% CI: 1.86-2.27) and 2.89 (95% CI: 2.28-3.79) among overweight, obese and severely obese women, respectively, compared with normal weight pregnant women. The meta-regression found no evidence that these estimates were affected by selected study characteristics. Our findings provide a quantitative estimate of the risk of cesarean delivery associated with high maternal body mass.

Abused boys, battered mothers, and male involvement in teen pregnancy.

BACKGROUND: The relationship between boyhood exposure to physical abuse, sexual abuse, or to a battered mother and subsequent risk of impregnating a teenage girl has not previously been examined. METHODS: In a retrospective cohort study set in a primary care clinic for adult members of a large health maintenance organization, questionnaire responses from 4127 men were analyzed. Respondents provided the age of the youngest female whom they had impregnated, their own ages at the time, and information regarding childhood exposure to physical or sexual abuse and battered mothers. We calculated the prevalence and adjusted odds ratio (OR) for having impregnated a teenage girl according to these 3 adverse childhood experiences, regardless of the male's age at the time of impregnation. Using logistic regression, ORs were adjusted for the male's age at time of survey, race, and education. RESULTS: Nineteen percent of the men reported that they had ever impregnated a teenage girl. During childhood, 32% of respondents had been physically abused, 15% sexually abused, and 11% had battered mothers. Compared with respondents reporting no abuse, frequent physical abuse or battering of mothers increased the risk of involvement in teen pregnancy by 70% (OR: 1.7; 95% confidence interval [CI]: 1.2-2.5) and 140% (OR: 2.4; 95% CI: 1.1-5.0), respectively. Sexual abuse as a boy at age 10 years or younger increased the risk of impregnating a teenage girl by 80% (OR: 1.8; 95% CI: 1.3-2.4); sexual abuse with violence increased the risk by 110% (OR: 2.1; 95% CI: 1.2-3.4). We found a dose-response relationship between the number of types of exposures and the risk of impregnating a teenage girl; men who reported all 3 types of exposures were more than twice as likely to have been involved than those with no exposures (OR: 2.2; 95% CI: 1.4-3.5). CONCLUSIONS: Boyhood exposure to physical or sexual abuse or to a battered mother is associated with an increased risk of involvement in a teen pregnancy-during both adolescence and adulthood. Because these exposures are common and interrelated, boys and adult men who have had these experiences should be identified via routine screening by pediatricians and other health care providers and counseled about sexual practices and contraception. Such efforts may prevent teen pregnancy and the intergenerational transmission of child abuse and domestic violence.

Outcomes of weight-based heparin dosing based on literature guidelines and institution individualization.

STUDY OBJECTIVE: To determine whether unfractionated heparin is optimally dosed using published weight-based guidelines. DESIGN: Six-month, prospective study. SETTING: University hospital. PATIENTS: Ninety-six patients in the weight-based unfractionated heparin-dosing group 1 (WBHD1; 37 men; mean age 66.9 +/- 15.1 years; mean weight 80.1 +/- 20.6 kg) and 68 patients in the WBHD2 (25 men; mean age 68.2 +/- 15.6 years; mean weight 82.0 +/- 19.6 kg). INTERVENTIONS: The WBHD1 received a 100-U/kg intravenous bolus followed by an 18-U/kg/hour continuous intravenous infusion. After 3 months, the protocol was modified, and the WBHD2 received a 90-U/kg bolus followed by a 16-U/kg/hour continuous infusion for 3 months. MEASUREMENTS AND MAIN RESULTS: Activated partial thromboplastin times (aPTTs), frequency of bleeding episodes that required blood transfusions, and the number of recurrent thromboembolic events were collected from both groups after 3 months on the study. In the WBHD1, 24 hours after starting heparin, 38.5% of patients had therapeutic aPTTs, and at 48 hours, 54.3% were therapeutic. In the WBHD2, 42.6% and 51.4% of patients had therapeutic aPTTs at 24 and 48 hours, respectively. There was no statistical difference between the WBHD1 and WBHD2 in the percentage of patients with therapeutic aPTTs. CONCLUSIONS: Weight-based heparin dosing resulted in low percentages of patients with therapeutic aPTTs. The use of weight alone to dose heparin may not be adequate to optimize therapy.

Pseudorabies virus glycoprotein K requires the UL20 gene product for processing.

Glycoprotein K (gK) of pseudorabies virus (PrV) has recently been identified as a virion component which is dispensable for viral entry but required for direct cell-to-cell spread. Electron microscopic data suggested a possible function of gK in virus egress by preventing immediate fusion of released virus particles with the plasma membrane (B. G. Klupp, J. Baumeister, P. Dietz, H. Granzow, and T. C. Mettenleiter, J. Virol. 72:1949-1958, 1998). For more detailed analysis, a PrV mutant with a deletion of the UL53 (gK) open reading frame (ORF) from codons 48 to 275 was constructed, and the protein was analyzed with two monoclonal antibodies directed against PrV gK. The salient findings of this report are as follows. (i) From the PrV UL53 ORF, a functional gK is translated only from the first in-frame methionine. From the second in-frame methionine, a nonfunctional product is expressed which is not incorporated into virions. (ii) When constitutively expressed in a stable cell line without other viral proteins, gK is only incompletely processed. After superinfection with gK-deletion mutants, proper processing is restored and mature gK is incorporated into virions. (iii) The UL20 gene product is specifically required for processing of gK. gK is not correctly processed in a UL20 deletion mutant of PrV, and superinfection of gK-expressing cells with PrV-UL20(-) does not restore processing. However, all other known structural viral glycoproteins appear to be processed normally in PrV-UL20(-)-infected cells. (iv) Coexpression of gK and UL20 restored gK processing at least partially. Thus, our data show that the UL20 gene product is required for proper processing of PrV gK.

Unintended pregnancy among adult women exposed to abuse or household dysfunction during their childhood.

CONTEXT: Studies have identified childhood sexual and physical abuse as a risk factor for adolescent pregnancy but the relationship between exposure to childhood abuse and unintended pregnancy in adulthood has, to our knowledge, not been studied. OBJECTIVE: To assess whether unintended pregnancy during adulthood is associated with exposure to psychological, physical, or sexual abuse or household dysfunction during childhood. DESIGN AND SETTING: Analysis of data from the Adverse Childhood Experiences Study, a survey mailed to members of a large health maintenance organization who visited a clinic in San Diego, Calif, between August and November 1995 and January and March 1996. The survey had a 63.4% response rate among the target population for this study. PARTICIPANTS: A total of 1193 women aged 20 to 50 years whose first pregnancy occurred at or after age 20 years. MAIN OUTCOME MEASURE: Risk of unintended first pregnancy by type of abuse (psychological, physical, or sexual abuse; peer sexual assault) and type of household dysfunction (physical abuse of mother by her partner, substance abuse by a household member, mental illness of a household member). RESULTS: More than 45% of the women reported that their first pregnancy was unintended, and 65.8% reported exposure to 2 or more types of childhood abuse or household dysfunction. After adjustment for confounders (marital status at first pregnancy and age at first pregnancy), the strongest associations between childhood experiences and unintended first pregnancy included frequent psychological abuse (risk ratio [RR], 1.4; 95% confidence interval [CI], 1.2-1.6), frequent physical abuse of the mother by her partner (RR, 1.4; 95% CI, 1.1-1.7), and frequent physical abuse (RR, 1.5; 95% CI, 1.2-1.8). Women who experienced 4 or more types of abuse during their childhood were 1.5 times (95% CI, 1.2-1.8) more likely to have an unintended first pregnancy during adulthood than women who did not experience any abuse. CONCLUSIONS: This study indicates that there may be a dose-response association between exposure to childhood abuse or household dysfunction and unintended first pregnancy in adulthood. Additional research is needed to fully understand the causal pathway of this association.

Live births resulting from unintended pregnancies: is there variation among states? The PRAMS Working Group.

CONTEXT: States need data on live births resulting from unintended pregnancies in order to assess the need for family planning services; however, many states do not collect such data. Some states may use extrapolated rates from other states. METHODS: Pregnancy Risk Assessment Monitoring System (PRAMS) data were assessed to explore the feasibility of extrapolating data on the percentage of live births resulting from unintended pregnancies from states that collect these data to states that do not. Data on women who had live births between 1993 and 1995 were examined for eight states: Alabama, Florida, Georgia, Michigan, New York (excluding New York City), Oklahoma, South Carolina and West Virginia. Logistic regression was used to determine state variation in the odds of delivering a live birth resulting from an unintended pregnancy after adjustment for maternal race, marital status, age, education, previous live birth and participation in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). RESULTS: The percentage of live births resulting from unintended pregnancy ranged from 33% in New York to 49% in Alabama, Georgia and South Carolina. Compared with women in Alabama, women in Oklahoma were more likely to deliver a live birth resulting from an unintended pregnancy (odds ratio of 1.2, confidence interval of 1.1-1.3) and women in New York State were less likely (odds ratio of 0.7, confidence interval of 0.6-0.8) to have such a birth. However, unmarried white women in New York had lower odds of having a live birth resulting from an unintended pregnancy and married black women in Michigan had higher odds of having a live birth resulting from unintended pregnancy than their counterparts in Alabama. Although the percentages varied, in all eight states women who were black, were unmarried, were younger than 20 years of age, had less than 12 years of education or had more than one child had higher percentages of live births resulting from unintended pregnancy than women with other demographic characteristics. CONCLUSIONS: Data on which women have the greatest risk of delivering a live birth resulting from an unintended pregnancy may be extrapolated from one state to another, but the rate of such births may overestimate or underestimate the problem from one state to another.

In Vitro activity of 6 antimicrobials against propionibacteria isolates from untreated acne papulopustulosa.

In the present study, MIC values of 6 antibiotics were determined for 70 Propionibacterium acnes and 13 P.granulosum strains from 71 untreated acne patients using the agar dilution method. The interpretation of in vitro results is difficult because there are only poor data about the concentrations of antibiotics achievable in the sebaceous gland infundibulum. Based on breakpoint concentrations according to DIN 58,944, no resistance was found against chlortetracycline, doxycycline, minocycline, and chloramphenicol. In contrast, 11% of the P.acnes and 31% of the P.granulosum strains were not susceptible in vitro to erythromycin at a breakpoint concentration of 4 micrograms/ml. The present study shows that these strains are not suppressed even at higher erythromycin concentrations up to 256 micrograms/ml. Data from the literature reporting ineffective treatment of patients carrying erythromycin-resistant P.acnes strains may be explained by our study. Concerning clindamycin, resistance was found in only 6.8% of P.acnes and in 0% of the P.granulosum strains. Since sensitivity was seen in 100% of the strains already at a concentration of 16 micrograms/ml, a therapeutic effect may be possible.

Completeness of ascertainment of prenatal smoking using birth certificates and confidential questionnaires: variations by maternal attributes and infant birth weight. PRAMS Working Group. Pregnancy Risk Assessment Monitoring System.

Birth certificate data frequently are used to monitor the prevalence of smoking during pregnancy. The authors used a two-sample capture-recapture method to estimate the completeness of ascertainment of prenatal smoking on birth certificates and on confidential questionnaires in six US states. Completeness of ascertainment was also examined according to maternal attributes and infant birth weight. The samples included white women who delivered a live infant between 1993 and 1995 in one of six states (Alabama, Alaska, Georgia, Maine, South Carolina, or West Virginia) and who responded to a questionnaire mailed to them 2-6 months postpartum as part of the Pregnancy Risk Assessment Monitoring System. State-specific sample sizes ranged from 2,647 to 4,795. The completeness of ascertainment ranged from 70.6% to 82.0% using birth certificates and from 86.2% to 90.3% using confidential questionnaires. In all six states, the birth certificates' completeness of ascertainment varied by maternal education and infant birth weight, and the questionnaires' completeness varied by maternal age. Both birth certificates and questionnaires underestimated the true extent of smoking during pregnancy among these white women. Differential reporting by birth weights recorded on birth certificates would result in an overestimated association between low birth weight and prenatal smoking.

Differences in the risk of homicide and other fatal injuries between postpartum women and other women of childbearing age: implications for prevention.

OBJECTIVES: This study compared injury deaths between postpartum women and other women aged 15 to 44. METHODS: Risk ratios and 95% confidence intervals (CIs) were computed for injury fatality rates. RESULTS: Fifty percent (29/58) of postpartum injury deaths were homicides, compared with 26% (427/1648) of injury deaths among nonpregnant, nonpostpartum women. For females aged 15 to 19, the homicide rate was 2.6 times higher (95% CI = 1.17, 5.95) for postpartum females than for other females. The motor-vehicle fatality rate was lower for postpartum females than for nonpregnant, nonpostpartum females (risk ratio = 0.30, CI = 0.18, 0.48). CONCLUSIONS: Postpartum females aged 15 to 19 years were at higher risk of homicide. Postpartum women were at reduced risk of motor-vehicle fatalities.

Pseudorabies virus glycoprotein gK is a virion structural component involved in virus release but is not required for entry.

The pseudorabies virus (PrV) gene homologous to herpes simplex virus type 1 (HSV-1) UL53, which encodes HSV-1 glycoprotein K (gK), has recently been sequenced (J. Baumeister, B. G. Klupp, and T. C. Mettenleiter, J. Virol. 69:5560-5567, 1995). To identify the corresponding protein, a rabbit antiserum was raised against a 40-kDa glutathione S-transferase-gK fusion protein expressed in Escherichia coli. In Western blot analysis, this serum detected a 32-kDa polypeptide in PrV-infected cell lysates as well as a 36-kDa protein in purified virion preparations, demonstrating that PrV gK is a structural component of virions. After treatment of purified virions with endoglycosidase H, a 34-kDa protein was detected, while after incubation with N-glycosidase F, a 32-kDa protein was specifically recognized. This finding indicates that virion gK is modified by N-linked glycans of complex as well as high-mannose type. For functional analysis, the UL53 open reading frame was interrupted after codon 164 by insertion of a gG-lacZ expression cassette into the wild-type PrV genome (PrV-gKbeta) or by insertion of the bovine herpesvirus 1 gB gene into a PrV gB- genome (PrV-gK(gB)). Infectious mutant virus progeny was obtained only on complementing gK-expressing cells, suggesting that gK has an important function in the replication cycle. After infection of Vero cells with either gK mutant, only single infected cells or small foci of infected cells were visible. In addition, virus yield was reduced approximately 30-fold, and penetration kinetics showed a delay in entry which could be compensated for by phenotypic gK complementation. Interestingly, the plating efficiency of PrV-gKbeta was similar to that of wild-type PrV on complementing and noncomplementing cells, pointing to an essential function of gK in virus egress but not entry. Ultrastructurally, virus assembly and morphogenesis of PrV gK mutants in noncomplementing cells were similar to wild-type virus. However, late in infection, numerous nucleocapsids were found directly underneath the plasma membrane in stages typical for the entry process, a phenomenon not observed after wild-type virus infection and also not visible after infection of gK-complementing cells. Thus, we postulate that presence of gK is important to inhibit immediate reinfection.

Live births resulting from unintended pregnancies: an evaluation of synthetic state-based estimates.

OBJECTIVES: Most states lack information on the proportion of live births resulting from unintended pregnancies. We evaluated a potential solution to the lack of data, a synthetic state-based estimate of the percentage of live births resulting from unintended pregnancies for the state of Georgia. METHODS: We constructed the synthetic estimate by standardizing the 1995 National Survey of Family Growth data by the race, marital status, and age distribution of Georgia residents ages 15-44 years who delivered a live birth during 1990-1994. Two surveys conducted in Georgia during the same period that collected information on unintended pregnancies were used for comparison: the Georgia Women's Health Survey (GWHS) and the Georgia Pregnancy Risk Assessment Monitoring System (PRAMS). RESULTS: The synthetic estimate (35.2%, 95% CI = 33.5%-36.7%) was not statistically different from the GWHS estimate (39.6%, 95% CI = 35.7%-43.5%), but was significantly lower than the Georgia PRAMS estimate (49.0%, 95% CI = 45.5%-52.5%). When we stratified by race, marital status, and age, the synthetic and GWHS estimates were statistically similar except for married females and females ages 25-34 years, for whom the synthetic estimates were lower. For all groups of females, the synthetic estimates were statistically lower than the Georgia PRAMS estimates. CONCLUSIONS: The synthetic estimate can be a useful method for states that need to know the overall magnitude of the percentage of live births resulting from unintended pregnancy for purposes such as program planning.

Delayed entry into prenatal care: effect of physical violence.

OBJECTIVE: To assess whether women who experienced physical violence by their partner during the 12 months before delivery were more likely to delay entry into prenatal care than were women who had not experienced physical violence. METHODS: We analyzed data from the Pregnancy Risk Assessment Monitoring System. The sample included 27,836 women who delivered live infants during 1993-1994 in nine states and were surveyed 2-6 months after delivery. We calculated risk ratios and 95% confidence intervals (CIs) to measure the association between physical violence within the 12 months before delivery and entry into prenatal care. RESULTS: The prevalence of delayed entry into prenatal care (entering after the first trimester) was 18.1% and that of reported physical violence was 4.7%. Overall, women who experienced physical violence were 1.8 times more likely (95% CI 1.5, 2.1) to have delayed entry into prenatal care than women who had not experienced such violence. When stratifying by selected maternal characteristics, this association was found only for groups of women who were 25 years of age or older or were of higher socioeconomic status. CONCLUSION: Older women and women of higher socioeconomic status who reported physical violence were more likely to delay entry into prenatal care than younger or less affluent women.

Prenatal smoking in two consecutive pregnancies: Georgia, 1989-1992.

OBJECTIVE: To explore the patterns of prenatal smoking among women whose first and second pregnancies ended in live births. METHODS: We used population-based data to explore prenatal smoking among 14,732 white and 8968 black Georgia residents whose first and second pregnancies ended in live births during 1989-1992. Smoking status was obtained from birth certificates linked for individual mothers. Because of demographic differences, we analyzed white and black women separately. RESULTS: Approximately 15% (2253) of white women and 4% (318) of black women smoked during their first pregnancy. Of those smokers, 69% (1551) of white women and 58% (184) of black women also smoked during their second pregnancy. For both white and black nonsmokers during the first pregnancy, low education was the most significant predictor of smoking during the second pregnancy, after adjusting for consistency of the father's name on the birth certificate, prenatal care, birth interval, mother's county of residence, and birth outcome. CONCLUSIONS: The prevalence of smoking in this study may be low because of underreporting of prenatal smoking on birth certificates. The majority of women who smoked during their first pregnancy also smoked during their second, suggesting that these women exposed their first infant to tobacco smoke both in utero and after delivery. Practitioners should offer smoking cessation programs to women during, as well as after, pregnancy. Pediatricians should educate parents on the health risks to young children of exposure to environmental tobacco smoke and refer smoking parents to smoking cessation programs.

Emergency surgery in hematologic patients.

Patients at risk for clinically significant bleeding and who require urgent or emergent surgical procedures are encountered. Usually local causes are responsible, but a generalized hematologic defect may be uncovered. Quickly and effectively distinguishing the cause may be critical to rapid treatment and survival. A careful history, appropriate use of laboratory tests (e.g., partial thromboplastin time, prothrombin time, and platelet count), and knowledge of possible causes are key to prompt diagnosis and treatment. Bleeding from multiple sites, spontaneous bleeding, or unexpectedly severe bleeding suggests a systemic process. Immunocompromised or suppressed patients or systemically ill patients with chronic hepatic renal, lymphatic, and hematologic disorders are seen with urgent surgical problems. The key is rapid diagnosis and effective systemic and local therapy to counter the problem. The syndrome of diffuse "medical bleeding" frequently confronts the surgeon treating a patient who has received transfusions of more than 1.5 times blood volume. The coagulation defect is almost always associated with hypothermia and acidosis. Treatment consists in control of large-vessel bleeding by appropriate surgical techniques, blunt packing, and tamponade of diffuse bleeding, rapid rewarming of the patient, and adequate resuscitation for shock. Transfusion of platelets and fresh frozen plasma is empiric initially and subsequently guided by the clinical and laboratory coagulation profiles of the patient.

The sexually sadistic serial killer.

This article explores characteristics and crime scene behavior of 20 sexually sadistic serial murderers. The pairing of character pathology with paraphilic arousal to the control and degradation of others is examined as it manifests itself in their murders. Commonalities across murders and across murderers are highlighted, i.e., the execution of murders that are well-planned, the use of preselected locations, captivity, a variety of painful sexual acts, sexual bondage, intentional torture, and death by means of strangulation and stabbing.