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We report on the chemical analysis of ultrathin (10 nm) polymer films using the attenuated total reflectance–Fourier transform infrared (ATR-FTIR) technique based on p-polarized infrared light and two types of enhancing substrates, that is, metallic (Au) and dielectric (Si). We selected low-temperature plasma-treated ∼10 nm thick polystyrene films as a test case for demonstrating the capability of the p-polarized ATR-FTIR, whose performance was further compared with the conventional X-ray photoelectron spectroscopy (XPS) techniques. Although ATR-FTIR cannot be used for quantitatively determining elemental compositions in polymers at which XPS excels, it is able to be operated under nonvacuum conditions and allows the study of hydrogen-containing moieties. By correcting the contact condition between the polymer surface and the ATR prism, the relative concentration of the chemical bonds from different samples can be compared. Because ATR-FTIR and XPS provide complementary information on chemical bonds, their combination provides a powerful approach for studying the chemical composition of polymers.

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P2VN‐b‐PAA is a novel diblock copolymer which has potential as a self‐assembled nanoscale patterning material. Thin spin cast P2VN‐b‐PAA films rapidly reorganize to vertical lamellar with exposure to acetone vapor. P2VN‐b‐PAA lamellar morphology was aligned by electric field under acetone vapor at a significantly faster rate and at lower electric field strengths than other polymer systems. Observed dry etching selectivity for P2VN to PAA were comparatively high for a variety of etch gases, consistent with estimations from Ohnishi and ring parameters. Block copolymer self assembled patterns were transferred to silicon via two‐step CF4and SF6etching.

Abstract: Introduction: Implantable cardioverter defibrillators (ICDs) are effective at reducing mortality in patients at high risk for sudden cardiac death (SCD) but can cause psychological distress and reduce quality of life (QOL). The full benefits of ICDs can only be achieved when the patient’s QOL and psychological status are maintained. We examined psychological status and QOL post ICD implantation; the relationship of psychological status to QOL; the relationship of time since implantation to psychological status and QOL; and the relationship of time since ICD implantation and age of patient to these variables. Methods and Results: A cross-sectional self-administered assessment of QOL, depression, anxiety, demographic characteristics and cardiovascular health history of patients (n = 48) who had received ICDs within the past 10 years at an urban hospital. Patients who had ICDs for longer experienced worse depression and QOL. Patients who were younger had worse depression, anxiety, and QOL. The combination of anxiety, depression, age, and time since ICD implant significantly predicted overall QOL and the psychosocial and physical dimensions of QOL explaining 55.5, 54, and 34.9% of the variance, respectively. Conclusion: Younger ICD patients are at highest risk for psychological distress and poor QOL. Longitudinal research would facilitate determination of the trajectory of changes in psychological status and QOL over the duration of the ICD experience.

Background This study was designed to investigate the tolerability, safety, and effect on left ventricular function of a new long-acting preparation of metoprolol, metoprolol succinate (CR/XL). Methods and Results Sixty patients were randomly assigned with a 2:1 ratio, drug versus placebo, administered with a gradually increasing dose of 12.5 to 150 mg of blinded medication during an 8-week period and continued for 6 months. The average peak dose achieved was 99 mg and 132 mg in the metoprolol succinate and placebo groups, respectively. The drug was well tolerated and there was no significant difference in drug withdrawals, New York Heart Association class, or quality of life assessment. The increase in left ventricular ejection fraction measure at baseline and 6 months measured by radioisotopic ventriculography was greater in the metoprolol succinate group (27.5% to 36.3%) than in the placebo group (26% to 27.9%) (P < .015). Examination of serial Holter electrocardiographic recordings indicate that metoprolol succinate therapy was associated with a significant (P < .05) decrease in total ventricular ectopy at 8 weeks of therapy and a decrease in ventricular couplets and nonsustained ventricular tachycardia at 8 through 26 weeks of therapy. No changes were observed in plasma norepinephrine during therapy except a transitory significant (P < .05) increase in N terminal proatrial natriuretic factor at 8 weeks in the metoprolol succinate group. Conclusions This study indicates that treatment with metoprolol succinate for a 6-month period is safe and well tolerated and is associated with an increase in left ventricular ejection fraction and a decrease in ventricular ectopic beats. (Am Heart J 1999;138:1158-65.)

Continuous elevation of the middle finger for 15‐60 min gave rise to modulation of the e.m.g. at 4‐6 Hz. A marked peak (50‐150% of the amplitude of the coexisting 8‐12 Hz peak) at 4‐6 Hz was produced in sixteen out of twenty‐one subjects. The 8‐12 Hz peak was also enhanced (2‐14 times with respect to its initial amplitude in eighteen subjects) during the course of the prolonged contraction but its frequency did not change. The 4‐6 Hz and the 8‐12 Hz peaks were present simultaneously; it is concluded that the two phenomena are separate entities. A step‐function mechanical perturbation of the finger generates, time‐locked to the stimulus, a train of waves at the frequency of the slow tremor, which can be abolished by local ischaemia. It is proposed that this slow tremor is due to an oscillatory process, possibly involving the reflex arc, but entailing a longer neuronal delay than that responsible for 8‐12 Hz tremor.

For the classical numerical radius f(A) of an n-by-n real or complex matrix A, we consider inequalities of the following two types. [image omitted] in which f and g are polynomials. In the latter case, the event in which f and g are simple powers is of special interest. We present a variety of particular results depending upon the dimension n and the classification of A or the polynomials. A number of natural questions remain open.

The role of the nitric oxide synthase (NOS) pathway in inhibiting the ability of Rickettsia prowazekii to initially infect (invade) mouse cytokine-treated, fibroblastic L929 cells and macrophagelike RAW264.7 cells and the ability of nitric oxide (NO) to damage isolated rickettsiae were investigated. Substantial amounts of nitrite (a degradation product of NO) were produced and the initial rickettsial infection was suppressed in cultures of L929 cells treated with crude lymphokine preparations (LK) or with gamma interferon (IFN-gamma) plus tumor necrosis factor alpha (TNF-alpha) but not in L929 cell cultures treated with IFN-gamma alone or TNF-alpha alone. The NOS inhibitors N(G)-methyl-L-arginine and aminoguanidine both inhibited nitrite production and prevented the suppression of the initial rickettsial infection. Antibody-mediated neutralization of the IFN-gamma in the LK also inhibited both nitrite production and suppression of the initial rickettsial infection. Cultures of RAW264.7 cells treated with IFN-gamma plus lipopolysaccharide exhibited suppression of the initial rickettsial infection, and the suppression was relieved by aminoguanidine. Addition of oxyhemoglobin (a scavenger of extracellular NO) during the rickettsial infection alleviated the suppression of the initial rickettsial infection observed in appropriately treated L929 cells and RAW264.7 cells. In addition, the oxyhemoglobin restored the rickettsia-mediated, rapid killing of the treated RAW264.7 cells. Incubation of isolated rickettsiae with NO inhibited their ability to infect L929 and IFN-gamma-treated RAW264.7 cells and to rapidly kill IFN-gamma-treated RAW264.7 cells. In contrast, incubation of L929 cells with a solution that contained NO and/or degradation products of NO did not affect their ability to be infected by rickettsiae. The data are consistent with the hypothesis that NO released from appropriately stimulated potential host cells kills extracellular rickettsiae and thus prevents the rickettsiae from infecting the cells.

Simultaneous recordings were made from fusimotor axons in the central ends of filaments of the masseter nerve, and from masseter and temporalis spindle afferents in the mesencephalic nucleus of the fifth cranial nerve in lightly anaesthetized cats. Fusimotor and alpha‐motor units in the masseter nerve were differentiated on the basis of their response to passive ramp and hold stretches applied to the jaw. Spindle afferents were identified as primary or secondary according to their dynamic index after administration of suxamethonium. The activity of a given fusimotor unit during reflex movements of the jaw followed one of two distinct patterns: so‐called ‘tonic’ units showed a general increase in activity during a movement, without detailed relation to lengthening or shortening, while ‘modulated’ units displayed a striking modulation of their activity with shortening, and were usually silent during subsequent lengthening. Comparison of the simultaneously recorded fusimotor and spindle afferent activity suggests that modulated units may be representative of a population of static fusimotor neurones, and tonic units of a population of dynamic fusimotor neurones. In these lightly anaesthetized animals, both primary and secondary spindle afferents showed increased firing during muscle shortening as well as during lengthening. This increase during shortening is not usually seen in conscious animals and reasons are given for the view that it is due to greater depression of alpha‐motor activity than of static fusimotor activity during anaesthesia. The results are discussed in relation to the theories of ‘alpha‐gamma co‐activation’ and of ‘servo‐assistance'; and it is suggested that static fusimotor neurones provide a ‘temporal template’ of the intended movement, while dynamic fusimotor neurones set the required dynamic sensitivity to deviations from the intended movement pattern.

Aged (12- to 14-month-old) C57BL oestrous mice exhibited significantly lower (P< 0·001) ovarian Δ5-3β-hydroxysteroid dehydrogenase (3β-HSD) concentration, specific activity and total content than young (3-month-old) oestrous mice, suggesting a decrease in the potential of the older animals to produce ovarian Δ4-3-oxosteroids. Mice in both age groups maintaining pregnancy to 10 or 18 days post coitum(p.c.) had similar values for activity of ovarian 3β-HSD. In the aged females in which foetal resorption had occurred, the majority of foetuses had been resorbed by 10 days p.c. However, ovarian 3β-HSD activity in these animals was not significantly different from that of young or aged mice maintaining pregnancy. By day 18, however, ovarian dehydrogenase activity in aged females failing to maintain pregnancy had decreased significantly. It is suggested that foetal death in aged mice is not the result of a deficiency in ovarian 3β-HSD, but rather may initiate luteal regression and consequently a decline in 3β-HSD.

Left ventricular automatic border detection (ABD) patterns were defined in the parasternal short-axis and the apical four-chamber views and were compared with pulsed-wave diastolic Doppler flow-velocity patterns of the mitral valve in 49 subjects (aged 39 to 87 years), 10 selected normal individuals, and 39 consecutive patients with high-quality echocardiographic Doppler studies and relaxation abnormalities (Doppler peak early diastolic velocity/peak late velocity ratio <1). Both short-axis and apical four-chamber views were useful in the assessment of diastolic function by ABD. However, in subjects with high-quality two-dimensional echocardiographic Doppler studies, ABD was technically more feasible in the apical four-chamber view (97%; 38/39 subjects) than in the short-axis view (64%; 25/39 subjects) and correlated better with Doppler parameters. Compared with normal subjects, patients with abnormal Doppler relaxation patterns showed significant differences in diastolic filling indexes obtained by the ABD technique. The ratio of peak rapid filling rate/peak atrial filling rate (PRFR/PAFR) obtained from the dA/dt waveform in the apical four-chamber view had the highest correlation with Doppler indexes (r=0.79). A PRFR/PAFR ratio of 1.5 best discriminated between normal individuals and subjects with relaxation abnormalities, with high sensitivity and specificity (95% and 100%, respectively). The PRFR/PAFR ratio obtained from the dA/dt waveform seemed to be a simple and useful method to distinguish between normal and abnormal left ventricular diastolic filling, as defined by Doppler echocardiography.