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Tapered silver halide fibers were used for the first time for high-sensitivity fiber evanescent wave spectroscopic (FEWS) measurements of chlorinated hydrocarbons (CHCs) in water at trace level. The sensor arrangement consisted of a tunable diode laser (TDL) source, a polymer-coated and tapered silver halide fiber, and a direct fiber/mercury cadmium telluride (MCT) detector coupling. A minimum detection limit of 50 μg L−1 was achieved by using a polyisobutylene-coated fiber with a 1:4 tapering ratio. The sensor response is in the minute range and shows reversible analyte enrichment.

Polymer-coated attenuated total reflection (ATR) elements have been used to compare the diffusion behavior and enrichment from aqueous solutions of three different chlorinated hydrocarbons (CHCs) — monochlorobenzene (MCB), chloroform (CF), and tetrachloroethylene (TeCE)—into different polymers. The influence of polymer properties such as glass transition temperature and crystallinity and the effect of the polymer background IR absorption and varying thicknesses of the polymer membranes to the detectability were investigated. The crystallinity and the glass transition temperature have a very pronounced influence on the velocity of the diffusion process, whereas the partition coefficient influences the amount of CHC diffusing into the polymer membrane. The time constants for 90% saturation of the polymer with the test analytes are in the range of 8 to 40 min, depending on the nature of the polymer and analyte. A linear calibration graph was obtained for simultaneous detection of all three test analytes in the range from 5 mg/L to 100 mg/L CHC with detection limits of 1.5 to 2 mg/L. Coefficients for CHC partitioning between water and polymers measured by ATR/IR were in good agreement with values determined by GC/MS.

In this work the influence of the substrate geometry on FT-IR microspectroscopical transmission measurements is reported with special emphasis on the impact on the lateral resolution. Mid-infrared transparent fibers (chalcogenide glass) and even substrates (zinc selenide ATR crystal) were sprayed with drops (drop size distribution: 15 to 150 μm in diameter) of an organic polymer with specific absorption bands in the mid-infrared range. Quadratic scans along the surface of the fiber and of the even substrate gave information about whether the drops distributed on the surface appear laterally resolved, by maintaining the local information in the resulting contour plot. Several scans with different microscopic apertures accentuate the relation between the diameter of the focused IR beam on the sample surface and the broadening of the drop image in the contour plot.

In this work the development and validation of a new MIR fiber-optic physicochemical sensor system for the continuous in situ analysis of chlorinated hydrocarbons (CHCs) in water is described. This study took advantage of the selectivity and sensitivity of fiber evanescent wave spectroscopy (FEWS) and the recent development of polycrystalline silver halide fibers. Since these fibers are transparent up to 20 μm, it was possible for the first time to develop a fiber-optic sensing system for CHCs, which have their strongest absorption bands > 10 μm. The silver halide fibers were coated with low-density polyethylene (LDPE) to enrich the CHC within the evanescent wave and to exclude the IR absorbing water from the measurement. For the quantitative in situ FEWS measurements, the coated silver halide fibers were coupled to a Fourier transform infrared (FT-IR) spectrometer using an off-axis parabolic mirror and a fiber-detector coupling system. This setup enabled the simultaneous in situ detection of the most common chlorinated hydrocarbons in concentrations between 1 to 50 mg/L in water by employing a fiber sensing part only 10 cm in length. A comparative analysis of waste water samples under participation of two experienced head space-gas chromatography (HSGC) laboratories showed good agreement of this continuous sensor system with the established standard techniques. The resulting working curve for tetrachloroethylene showed a correlation coefficient of r2 = 0.968 and a relative standard deviation of 17% in the range from 1 to 10 ppm.

Objective: To review the published studies on the sex distribution of hypochondriasis, and to examine sex differences in hypochondriacal concerns and in attitudes toward illness. Method: The Illness Attitude Scales, Factors 2 and 3 of the Whiteley Index and the Symptom Checklist-90 (SCL-90) were administered to fifty randomly-selected female family practice patients ages eighteen to sixty-five, and to male patients matched by age in decades. From a pool of 130 consecutive nonpsychotic psychiatric outpatients, fifty females and fifty males were matched with the family practice patients. Results: Although females rated themselves as more depressed than males in both groups, there were no significant differences between the sexes in hypochondriacal fears and beliefs. Psychiatric male patients reported the most adverse effects of bodily symptoms on work and leisure. There were no other significant differences between the sexes in any of the other attitudes toward illness or symptoms. Hypochondriacal concerns were more common in the psychiatric patients than in the family practice patients of both sexes. Conclusion: The review of published studies on the sex distribution of hypochondriasis suggests that disease phobia is more common in females, except for the cardiophobic syndrome, which is more common in males. The other reported differences are inconsistent and appear to be caused by referral biases, varying diagnostic criteria, and cultural factors. In our study, we found no substantial differences between males and females in hypochondriacal concerns and attitudes toward illness.

In a previous study ten women with hyperprolactinemia and amenorrhea had significantly higher Symptom Questionnaire scores for depression, hostility and anxiety than patients with amenorrhea only and a matched nonpatient employees group. The hyperprolactinemic patients and employees were compared with ten women on their seventh day after childbirth who had been matched for sociodemographic variables and had similar prolactin levels. Hostility was significantly higher in postpartum patients than employees and did not differ significantly from that of women with hyperprolactinemic amenorrhea. Postpartum hyperprolactinemic women did not differ significantly from the employees for anxiety and depression, which was significantly lower than in the amenorrheic patients. In several mammals aggression occurs concurrently with lactation. The studies in humans suggest an association of high prolactin levels with hostility.

Beliefs and attitudes which can be responsible for hypochondriacal behavior were explored by administering the Illness Attitude Scales and two distress scales to patients attending a family practice clinic, nonpsychotic psychiatric outpatients and a random group of employees. Family practice patients were more distressed, had more hypochondriacal concerns and had more bodily preoccupations than employees and took more precautions about their health. Psychiatric patients were more distressed and had more fears about illness and death than family practice patients, yet took fewer precautions about their health. The findings appear to have implications for treatment.