60 dB high-extinction auto-configured Mach-Zehnder interferometer.

Imperfections in integrated photonics manufacturing have a detrimental effect on the maximal achievable visibility in interferometric architectures. These limits have profound implications for further technological developments in photonics and in particular for quantum photonic technologies. Active optimization approaches, together with reconfigurable photonics, have been proposed as a solution to overcome this. In this Letter, we demonstrate an ultrahigh (>60 dB) extinction ratio in a silicon photonic device consisting of cascaded Mach-Zehnder interferometers, in which additional interferometers function as variable beamsplitters. The imperfections of fabricated beamsplitters are compensated using an automated progressive optimization algorithm with no requirement for pre-calibration. This work shows the possibility of integrating and accurately controlling linear-optical components for large-scale quantum information processing and other applications.

Shared decision making: audiology student perspectives.

Introduction: Shared decision making is a concept in healthcare that actively involves patients in the management of their condition. The process of shared decision making is taught in clinical training programmes, including Audiology, where there are several options for the management of hearing loss. This study sought to explore the perception of Healthcare Science (Audiology) student views on shared decision making. Methods: Twelve students across all years of the BSc Healthcare Science degree took part in three semi-structured focus groups. Four students were work-based learners, and eight students were enrolled on the standard pathway. Data were analysed using Thematic Analysis. Results: Students' definition and understanding of shared decision making was influenced by three key factors that were based on using a range of resources, implementation of a decision aid, and recognising Ida Institute as a pinnacle of shared decision making. Students also identified their roles as the future of healthcare workforce and the importance of disseminating best practice. Conclusion: Shared decision making is valued by students in their roles as healthcare trainees. This study data will enhance teaching practices for healthcare science students in audiology training. Future research involving patient views in clinical training is vital.

The effect of infection history on the fitness of the gastrointestinal nematode Strongyloides ratti.

SUMMARY: Hosts in nature will often acquire infections by different helminth species over their lifetime. This presents the potential for new infections to be affected (particularly via the host immune response) by a host's history of previous con- or hetero-specific infection. Here we have used an experimental rat model to investigate the consequences of a history of primary infection with either Nippostrongylus brasiliensis, Strongyloides venezuelensis or S. ratti on the fitness of, and immunological response to, secondary infections of S. ratti. We found that a history of con-specific, but not hetero-specific, infection reduced the survivorship of S. ratti; the fecundity of S. ratti was not affected by a history of either con- or hetero-specific infections. We also found that a history of con-specific infection promoted Th2-type responses, as shown by increased concentrations of total IgE, S. ratti-specific IgG1, rat mast cell protease II (RMCPII), IL4 (but decreased concentrations of IFNgamma) produced by mesenteric lymph node cells in response to S. ratti antigen. Additionally, S. ratti-specific IgG1 was positively related to the intensity of both primary and secondary infections of S. ratti. Hetero-specific primary infections were only observed to affect the concentration of total IgE and RMCPII. The overall conclusion of these experiments is that the major immunological effect acting against an infection is induced by the infection itself and that there is little effect of prior infections of the host.

Hypothalamic-pituitary-adrenal axis function and the cellular immune response in former preterm children.

CONTEXT: Animal data suggest that adverse early experiences may affect endocrine and immune functioning in later life. OBJECTIVE: Our objective was to assess the impact of preterm delivery on hypothalamus-pituitary-adrenal axis functioning, heart rate responses, and immune function. PARTICIPANTS: Former preterm children [aged 8-14 yr (n = 18)], sex and age-matched full-term born control children (n = 18), data on birth weight, gestational age, birth weight for gestational age (in sd units), actual body weight, height, and body mass index were assessed. DESIGN AND OUTCOME MEASURES: Subjects were exposed to a standardized laboratory stressor ("Trier Social Stress Test for Children"). Cortisol in saliva was determined in 10-min intervals before and after the stress test; heart rates were obtained continuously during the stress test. Additional assessment of saliva cortisol was performed: 1) on 3 consecutive days after awakening and at +10, +20, and +30 min (morning cortisol); and 2) at 0800, 1400, 1600, and 1900 h (short diurnal profile). Measurement of the delayed type hypersensitivity reaction to seven recall antigens [Multitest cellular mediated immunity (Multitest-Immignost, Biosyn, Fellbach, Germany)]. RESULTS: Exposure to the Trier Social Stress Test for Children yielded significantly increased cortisol levels [F (8, 232) = 19.86; P < 0.001] and heart rates [F (38, 988) = 10.46; P < 0.001], however, no difference between former preterms and full-terms could be observed. No between-group differences were found in the short diurnal cortisol profile. Former preterms showed significantly higher cortisol levels after awakening [F (3, 102) = 3.14; P < 0.05]. In addition, a significantly suppressed delayed type hypersensitivity response [reduced number of positive antigens (t = -2.64, P < 0.05); induration (t = -2.4, P < 0.05)] was found in former preterms. CONCLUSION: The data suggest that preterm delivery may be associated with altered endocrine and immune functions well into late childhood.

Potential Use of Multiplex PCR in Diagnosis of Tuberculous Meningitis.

Accurate and rapid diagnosis of tuberculous meningitis (TBM) is important for early administration of treatment. In this study, we have evaluated the diagnostic value of smear, culture, multiplex PCR and GeneXpert MTB/RIF to detect M. tuberculosis in cerebrospinal fluid (CSF) samples from patients with suspected TBM registered in Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia. Of the 55 CSF samples collected, 12 (21.8%) samples were positive by multiplex PCR, 3 (5.4%) by GeneXpert MTB/RIF and only 1 (1.8%) by smear and culture. Multiplex PCR showed higher sensitivity to detect M. tuberculosis in patients with suspected TBM and has the potential to be used as a diagnostic method.

Assessing exposure to disinfection by-products in women of reproductive age living in Corpus Christi, Texas, and Cobb county, Georgia: descriptive results and methods.

We conducted a field study in Corpus Christi, Texas, and Cobb County, Georgia, to evaluate exposure measures for disinfection by-products, with special emphasis on trihalomethanes (THMs). Participants were mothers living in either geographic area who had given birth to healthy infants from June 1998 through May 1999. We assessed exposure by sampling blood and water and obtaining information about water use habits and tap water characteristics. Two 10-mL whole blood samples were collected from each participant before and immediately after her shower. Levels of individual THM species (chloroform, bromodichloromethane, dibromochloromethane, and bromoform) were measured in whole blood [parts per trillion (pptr)] and in water samples (parts per billion). In the Corpus Christi water samples, brominated compounds accounted for 71% of the total THM concentration by weight; in Cobb County, chloroform accounted for 88%. Significant differences in blood THM levels were observed between study locations. For example, the median baseline blood level of bromoform was 0.3 pptr and 3.5 pptr for participants in Cobb County and Corpus Christi, respectively (p = 0.0001). Differences were most striking in blood obtained after showering. For bromoform, the median blood levels were 0.5 pptr and 17 pptr for participants in Cobb County and Corpus Christi, respectively (p = 0.0001). These results suggest that blood levels of THM species vary substantially across populations, depending on both water quality characteristics and water use activities. Such variation has important implications for epidemiologic studies of the potential health effects of disinfection by-products.

Pregnancy related to infertility diagnosis, number of attempts, and age in a program of in vitro fertilization.

Three hundred nineteen infertility patients who did not become pregnant with standard therapies presented to Norfolk for in vitro fertilization between January 1981 and December 1983. There were 560 laparoscopic cycles with 105 pregnancies. The pregnancy rate was 18.8% by cycle, 24.5% by transfer, and 33% by patient. The overall pregnancy rate was found to be independent of infertility diagnosis, age, and number of attempts.

Cumulative pregnancy rates for in vitro fertilization.

Data on 575 couples undergoing 1057 consecutive cycles of in vitro fertilization (IVF) were used to calculate cumulative pregnancy rates for repeated IVF cycles. Excluding preclinical abortions and couples in whom the male partner had poor semen parameters, calculated cumulative pregnancy rates for cycles 1 to 6 were 13.6%, 24.8%, 37.2%, 47.8%, 52.2%, and 59.6%, respectively. A parametric model used to fit these data yielded a strong correlation between observed and predicted pregnancy rates (r = 0.99, P less than 0.001). Predicted cumulative pregnancy rates after 9 and 12 cycles were 75% and 84%, respectively. Excluding preclinical abortions, the pregnancy rate per cycle was approximately constant, at approximately 15% over repeated cycles. As the cost of IVF declines and as treatment cycles become more easily tolerated, persistence in IVF can lead to successful pregnancy for a large proportion of couples.

The importance of the follicular phase to success and failure in in vitro fertilization.

One hundred seventy-five cycles in patients with irreparable tubal disease were stimulated by human menopausal gonadotropin/human chorionic gonadotropin for the purpose of in vitro fertilization. As judged by the height of the peripheral estradiol response, the patients were classified as high, intermediate, or low responders. In addition, the estradiol pattern of the response was found to be separable into six categories. The pregnancy rate was found to be related to the height and to the pattern of peripheral response. The overall pregnancy rate in this consecutive series was 19% but varied according to the height and pattern of response from 40% to 0%.

The program for in vitro fertilization at Norfolk.

Several aspects of the program of in vitro fertilization (IVF), or, as it is called in Norfolk, the program for the Vital Initiation of Pregnancy (VIP), have been or are in the process of publication. However, because there has been no overall account, it seems appropriate to give a brief report of a general nature covering the period from the beginning of the effort in late February 1980 through December 31, 1981. Although minor changes were constantly made in the protocol, there were two major revisions. Therefore, a discussion of the program during three distinct periods, i.e., 1980, 1981-Phase I, and 1981-Phase II, is necessary. During 1980 and 1981 all patients had either no fallopian tubes or irreparable tubes.

PIP: The general procedures utilized in the 2 major phases of the Norfolk in vitro fertilization program in 1981 are described. When the program began, it was believed desirable to exploit the natural menstrual cycle instead of a stimulated controlled cycle, to aspirate the single dominant follicle at the last possible moment prior to expected ovulation, since it was believed impossible to further mature an oocyte in vitro; to utilize a reliable method to predict the hour of ovulation; to utilize a proven aspiration technique; to take extreme measures to maintain a special environment for the oocyte; and to provide means of inseminating the egg with the least possible delay. The results for 1980 were disappointing; from 41 laparoscopies only 19 fertilizable ova were obtained, and no pregnancies resulted from in vitro and in vivo attempts. For phase I beginning in 1981, a protocol was adopted calling for stimulated controlled ovulation using human menopausal gonadotropin (hMG). Exogenous human chorionic gonadotropin (hCG) was used to substitute for the midcycle luteinizing hormone (LH) surge. Laparoscopy for follicular aspiration was scheduled 36-38 hours after hCG administration. The use of a realtime sector ultrasonograph to monitor follicular growth became routine, quality control in the laboratory was tightened, and supplementary maturation in vitro of oocytes prior to insemination was initiated. In Phase I, 48 fertilizable eggs were obtained in 26 of 31 cycles; cleavage was obtained in eggs from 12 cycles, and 2 pregnancies occurred. In 1981-Phase II, several changes in procedures were made. Serum E2 values became available on a daily basis, so that hMG injections could be controlled. There were further improvements in laboratory quality control, such as measures to insure a toxin-free water supply. It became possible to incubate morphologically immature oocytes which subsequently accepted fertilization. In 1981 Phase II, fertilizable eggs were obtained in 22 of 24 laparoscopic cycles, eggs were fertilized from 21 of the 22 cycles, transfers were made in 19 cycles, and there were 5 pregnancies. The importance of transferring more than 1 conceptus became evident from the 31 cycles with transfers: the pregnancy rate was 13% with transfer of a single conceptus, 31% with 2, and 50% with 3.

Safety and tolerability of zalcitabine (ddC) in patients with AIDS or advanced AIDS-related complex in the European expanded access programme.

This international expanded access programme was initiated to provide zalcitabine (o 75 mg three times daily) to patients with AIDS or advanced ARC who had failed, were no longer able to tolerate or were ineligible to receive zidovudine (ZDV). Data are available from 517 patients. No unexpected adverse events occurred during the study with 13.2% of patients discontinuing treatment due to drug-related adverse events. Peripheral neuropathy (PN) was the most common adverse event reported. This was considered to be at least possibly related to zalcitabine in 12.2% of patients, with only 2.3% of patients withdrawing from the study due to zalcitabine-associated PN. Patients with a baseline diagnosis of AIDS and a CD4 count

Pro-drinking messages and message environments for young adults: the case of alcohol industry advertising in African American, Latino, and Native American communities.

This paper examines targeted alcohol advertising in three ethnic communities: African Americans, Latinos, and Native Americans in the U.S. We focus on the appropriation of cultural systems and the reinvention of them as commodities to consumers. We outline the specific strategies used in each ethnic community. For African Americans, there is an emphasis on selling malt liquor to young adults through the use of "power" and gang-related images. For Latinos, there is an appropriation of historical and cultural symbols such as the national flags and maps of Mexico and Central America. Native Americans have coalesced to keep the image of a chief and warrior, Crazy Horse, from being used to market malt liquor. Each of the ethnic groups is engaged in action to prevent alcohol-related problems in their communities. Generating and implementing solutions is a universal social responsibility.

Some physiological aspects of bone marrow pressure.

An investigation was made into some of the hemodynamic properties of bone. The parameters studied were bone marrow and medullary venous pressures. The resting level and changes in the two pressures were measured under autoperfusion and constant-flow perfusion conditions. Changes were induced either by drugs or by alteration in blood flow. Marrow pressure was measured with a new tonometric technique. A specially constructed miniature pressure transducer was utilized as the tonometer. Trauma-induced hemorrhage of the marrow was avoided. The marrow pressure was measured across an intact endosteal membrane. The pressure of the normal bone marrow and the medullary venous pressure in the anesthetized dog were nearly equal, approximately twenty millimeters of mercury and about 17 per cent of systemic blood pressure. These values were found whether measured simultaneously or separately in comparable groups of dogs under a variety of conditions. Induced changes in the two pressures produced either by changes in perfusion rate or by drugs were also nearly equal and in the same direction.

Surgical treatment of internal derangements of the temporomandibular joint. A long-term study.

A long-term surgical follow-up study of 176 patients (211 joints) with documented internal derangements of the temporomandibular joint was carried out. Arthrograms and tomograms were used in all cases. Forty of the patients (49 joints) were nonsurgical control patients. Diagnostic staging of the cases was accomplished as previously published. A clinical/radiologic assessment index was derived, which included seven measured parameters. Surgical patients, grouped by diagnostic stages and selected operations, were compared with each other and with control patients over the follow-up period (average, 8.1 years; range, 5 to 14 years). The surgical procedures included meniscectomy, reconstructive arthroplasty, and arthroplasty with temporary Silastic (Dow Corning Wright, Arlington, Tenn) implant. The overall success rate for surgical cases with all stages and procedures was 93.8%. In contrast, the control group demonstrated significant clinical and radiographic progression. The surgical results were stage dependent for the same operative procedure. Significantly better success rates were obtained in early-stage cases (96.9%) than in late-stage cases (89.4%). With respect to comparison of operative procedures, it was found that reconstructive arthroplasty provided results superior to those of meniscectomy. There was no significant difference between results obtained by meniscectomy and those by arthroplasty with a temporary Silastic implant. Long-term stability was excellent in most cases. Follow-up radiographic changes for the surgical group were less than expected. On the other hand, radiographic analysis of the control group demonstrated progressive degenerative changes in 73.5% of cases. Complications over the entire study were rare. It was concluded that surgery can provide successful long-term results in the treatment of internal derangements.

Internal derangements of the temporomandibular joint. Pathological variations.

A retrospective analysis of 540 operated cases (740 joints) of internal derangements of the temporomandibular joint was carried out. Observations of this patient population provided the basis for describing pathological variations of internal derangements. Radiologic studies, including tomograms and arthrograms or magnetic resonance scans, and surgical/pathological findings were correlated with clinical data in each case. It was found that clinical manifestations varied in a characteristic way and were directly related to the degree of pathological change and time course. Various stages of internal derangements were identified. Pathophysiological mechanisms responsible for the observed changes, as well as clinical signs and symptoms and causal factors, were discussed. Internal derangements are organic lesions that appear to be progressive and are probably of traumatic origin. The view is given that internal derangements represent the basic pathological entity responsible for clinical manifestations of what has been known as the temporomandibular joint pain-dysfunction syndrome or similarly described conditions. Effective clinical management takes on new importance because progression to advanced degenerative states may occur.

Temporomandibular joint imaging. Practical application of available technology.

Clinical afflictions of the temporomandibular joint (TMJ) are common, but TMJ afflictions remain one of the most poorly understood and controversial areas of clinical practice. Theories of TMJ pathophysiology, diagnosis, treatment, and patient disposition abound. Many afflicted patients have undergone expensive, protracted, and fruitless therapeutic endeavors, many of which are without scientific basis, causing many health insurers to exclude evaluation and treatment of TMJ disorders from coverage. Medical imaging has a central role in establishing a correct diagnosis. Available imaging procedures include roentgenography, arthrography, videofluoroscopy, magnetic resonance imaging, and computed tomography.

Three-dimensional computed tomography in maxillofacial surgical planning.

Fifty-four maxillofacial three-dimensional computed tomographic examinations were performed during a 12-month period for the purpose of surgical planning. Pathologic entities in the series included trauma, neoplasia, cleft palate, and other developmental anomalies. Computer-assisted mandibular disarticulation was performed routinely after each study to permit direct viewing of the mandible or maxilla in isolation. Three-dimensional computed tomography is a useful technique for maxillofacial surgical planning.

Modeling the effects of water usage and co-behavior on inhalation exposures to contaminants volatilized from household water.

The volatilization of volatile organic chemicals during domestic water usage can result in significant indoor air concentrations, and the subsequent inhalation of these contaminants is an important route of exposure. The magnitude of these exposures is highly dependent on the activities undertaken by the exposed individual, as well as the activities of other occupants of the home. The indoor air quality-exposure Model for the Analysis of Volatiles and Residential Indoor Air Quality (MARVIQ) was used to ascertain the impact of water-use activities on the potential contaminant dose to household members. Human time-activity patterns of various population groups were sampled from the California Air Resources Board database, applying distributions of water-use occurrence and water-use duration to each activity based on survey results. Indoor air concentrations in a sample house and the resulting potential inhalation dose to the occupants were computed for different individuals and pairs of individuals to test for exposure and coexposure effects. The simulated daily exposure is well described by a simplified equation that is a function of the amount of time the individual spends in the shower, the bath, and the bathroom; the total water usage in the home; and the fraction of time the individual is at home. These results can be used to identify high-risk populations, individuals, and households. The study also demonstrates the importance of further research on joint time-activity patterns in multiperson households for assessment of exposure and coexposure effects.

Mandibular retrusion, temporomandibular joint derangement, and orthognathic surgery planning.

One-hundred consecutive orthognathic surgery candidates with mandibular retrusion were selected for retrospective analysis. Patients had undergone imaging studies that included magnetic resonance imaging (MRI) of both temporomandibular joints to assess the presence or absence, stage, and activity of suspected internal derangement(s). Patients were divided into stable and unstable deformity groups based on the presence or absence of change in their facial contour and/or occlusal disturbances in the 24 months prior to evaluation. Each of the 58 unstable and 30 of 42 stable patients were found to have internal derangements of at least one temporomandibular joint. The degree of joint degeneration directly paralleled the severity of retrognathia in most cases. We concluded that temporomandibular joint internal derangement is common in cases of mandibular retrusion and leads to the facial morphology in a high percentage of patients. Preoperative temporomandibular joint imaging with MRI is recommended prior to orthognathic surgical correction of retrognathic deformities.

Analysis of sampling strategies for estimating annual average indoor NO2 concentrations in residences with gas ranges.

Range gas consumption in households tends to follow an annual cycle resembling a sinusoid, with peak consumption during the winter. When outdoor NO2 concentrations have a constant or small impact, the resulting indoor NO2 concentrations also tend to resemble an annual sinusoid. Optimal monitoring strategies can be designed to take advantage of this knowledge to obtain a better estimate of the true annual average gas consumption or indoor NO2 concentration. Gas consumption data, together with measured outdoor concentrations, house volumes, sampled emission rates, air exchange rates, and NO2 decay rates, are used to model weekly indoor NO2 concentrations throughout the year. Based on the modeling results, various monitoring strategies are evaluated for their accuracy in estimating the annual mean. Analysis of the results indicates that greater accuracy is attained using samples equally spaced throughout the year. In addition, the expected error for various monitoring strategies and various numbers of equally spaced samples is quantified, and their ability to classify homes into correct concentration categories is assessed.