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A study is presented on changes in the structure and the chemical composition of antimony-doped semiconducting glazes before and after exposure to AC and DC electric fields in outdoor conditions and in the laboratory using the rotating-wheel-dip (RWD) test. Surface sensitive techniques such as scanning electron microscopy (SEM) in combination with energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and secondary ion-mass spectrometry (SIMS) were employed to characterize the materials. Aging in the form of crater building, surface cracking and pitting as well as formation of a tin oxide rich layer took place under both AC and DC exposure. However, the damage was much more severe under DC voltage. Similar aging changes could be obtained in the laboratory after only a few days of the RWD test. In the field, leakage currents were monitored for evaluating the electrical performance of the samples. On new samples, the currents varied only slightly depending on weather conditions. However, during rainfall periods the leakage currents on samples exposed to DC voltage for a longer period were significantly increased compared to the new state, while the currents on AC exposed samples remained unchanged. No flashovers occurred during the 4-month testing. Thermal runaway on samples exposed to DC voltage in the field caused the appearance of black spots in the glaze. Their origin and chemical composition are still under investigation.

The distributions of protons after the absorption of positive pions by 3 He at 118, 162 and 239 MeV are presented. A decomposition of the three-nucleon cross section in terms of initial state interactions and other processes is given, based upon simple models. A clear signal of initial state interactions is visible in the data, diminishing at the lower energies.

A Large Acceptance Detector System (LADS) has been designed and built at the Paul Scherrer Institute to study multiparticle final states following pion-nucleus absorption. It consists of a 28-sector cylinder of plastic scintillators of 1.6 m active length and 1.4 m diameter, two cylindrical wire chambers, and two 14-sector plastic scintillator end-caps which close each end. The nearly 4π solid angle coverage of this detector minimizes uncertainties associated with extrapolations over unmeasured regions of phase space. The design and the performance of the LADS detector are presented.

to examine the effect of cycle phase or a low dose oral contraceptive on exercise performance in young women.As controls, 15 men were tested twice by a maximal treadmill test (Vo2 max) and by an endurance run 14 d apart to determine performance variability from causes other than hormonal fluctuations. Ten women ages 18-30 were then tested for Vo2 max and endurance in the same way in both the follicular and the luteal phase (random order, ovulation assessed by sonography). They were then randomly assigned to placebo (n = 3) or oral contraceptive (1 mg norethindrone and 35 micrograms ethinyl oestradiol) (n = 7) for 21 days. Tests were repeated during the first and third weeks of treatment. Vo2 max and endurance tests were compared in the men and control cycle of the women by using independent t tests on percent change. The data for both cycles in the women were analysed by repeated measures ANOVA.There was no difference in per cent change in total test time, Vo2 max, or breathing frequency between the men and women in either test. Data obtained during the Vo2 max test revealed no difference between the follicular and luteal phases of the menstrual cycle for total test time [11.8 (SD 2.3) v 12.6 (2.3) min], Vo2 [41.6 (12.1) v 39.7 (11.4) ml.kg-1.min-1], or breathing frequency [26.8 (3.5) v 27.3 (9.9) breaths.min-1] respectively, or during the first and third weeks of treatment [total test time 12.0 (2.5) v 12.8 (2.4) min; Vo2 37.3 (7.4) v 41.0 (12.4) ml.kg-1.min-1; breathing frequency 27.8 (4.2) v 27.7 (3.4) breaths.min-1, respectively]. Data obtained during the endurance test revealed no difference between the follicular and luteal phase of the menstrual cycle for total test time [20.5 (15.7) v 16.2 (8.5) min], Vo2 [37.5 (9.4) v 32.9 (8.1) ml.kg-1.min-1], or breathing frequency [32.0 (6.0) v 33.2 (5.1) breaths.min-1, respectively], or during the first and third weeks of treatment [total test time 32.3 (34.9) v 30.6 (30.1) min; Vo2 33.9 (10.1) v 35.2 (8.6) ml.kg-1.min-1; breathing frequency 34.0 (5.9) v 34.8 (5.3) breaths.min-1, respectively].Neither cycle phase nor a low dose oral contraceptive containing 1 mg norethindrone adversely affects performance during a maximal treadmill test or endurance run.The authors examined the effect of cycle phase or a low dose oral contraceptive on the exercise performance of young women. As controls, 15 men were tested twice by a maximal treadmill test and by an endurance run 14 days apart to determine performance variability from causes other than hormonal fluctuations. 10 women aged 18-30 were then tested by maximal treadmill test and endurance in the same manner in both the follicular and luteal phase. They were then randomly assigned to placebo or oral contraceptive for 21 days. Tests were repeated during the first and third weeks of treatment. Maximal treadmill test and endurance tests were compared in the men and control cycle of women using independent t tests on percent change. Neither cycle phase nor a low dose oral contraceptive containing 1 mg norethindrone was found to adversely affect performance during a maximal treadmill test or endurance run.

Measurements have been made of [pi][sup +] absorption on [sup 3]He at [ital T][sub [pi]][sup +]=118, 162, and 239 MeV using the Large Acceptance Detector System. The nearly 4[pi] solid angle coverage of this detector minimizes uncertainties associated with extrapolations over unmeasured regions of phase space. The total absorption cross section is reported. In addition, the total cross section is divided into components in which only two or all three nucleons play a significant role in the process. These are the first direct measurements of the total and three nucleon absorption cross sections.

The presence and functional role of the cyclic nucleotide signal transduction system was investigated in platelets from patients with myeloproliferative disorders. Platelets from certain patients with chronic myelocytic leukemia showed decreased expression of cGMP-dependent protein kinase, and platelets from two such patients were studied in some detail. These platelets had very little if any cGMP-dependent protein kinase but a normal level of cAMP-dependent protein kinase. They also contained a normal level of VASP (vasodilator-stimulated phosphoprotein, a specific substrate of both cAMP- and cGMP-dependent protein kinase), as well as a functionally intact prostaglandin E1-stimulated cAMP-mediated VASP phosphorylation. In contrast, sodium nitroprusside-stimulated VASP phosphorylation was severely impaired in these cGMP-dependent protein kinase-deficient platelets, despite an exaggerated cGMP response to sodium nitroprusside. Furthermore, whereas selective activation of the cGMP-dependent protein kinase by 8-(4-chlorophenylthio)-cGMP strongly inhibited the ADP- or thrombin-evoked calcium mobilization from intracellular stores in normal platelets, this agonist-evoked calcium response was not inhibited by the cGMP analog in cGMP-dependent protein kinase-deficient platelets. The results demonstrate a defect in the nitrovasodilator-/cGMP-regulated signal transduction system in human platelets from some patients with myeloproliferative disorders, and underscore that a cGMP-dependent protein kinase regulatory system, distinct from that of cAMP-dependent protein kinase or other cGMP-dependent effectors is operative in normal human platelets.

Human evolutionary research in Eastern Germany, limited in this paper to the origins and evolution of Pleistocene man, has mainly focused during the last decade on theoretical aspects of the evolution of man and human society from multiple and interdisciplinary perspectives. An interdisciplinary working group «Probleme der Menschwerdung» was founded in 1977. About 30 specialists from various fields have discussed problems of the origins and evolution of man and human society under interdisciplinary aspects. The activities, difficulties and results of this cooperation will be outlined in this paper. There will also be given a progress report on the disciplinary initiated research on local sites as well as on general aspects and problems.

Human serum and low density lipoproteins (LDLs) were shown to inactivate endotoxin (lipopolysaccharide [LPS]) by testing the effect of LPS interactions with serum or LDL on the activation of human monocytes. Sera and LDL preparations from four patients with familial hypercholesterolemia were used to demonstrate the inhibition of LPS from inducing interleukin-1 release. Before LDL removal by immunoapheresis, the patients' sera were able to inactive approximately fivefold more LPS than after LDL removal. The LPS-inactivating capacity lost during apheresis could essentially be retrieved in the LDL-rich eluate from the immunoadsorption columns. Because patients were treated frequently with immunoapheresis, their LDL levels before LDL removal were not markedly elevated. These patients' sera before LDL removal were shown to inactivate amounts of LPS comparable to those inactivated by the sera from three healthy volunteers. LDL prepared by ultracentrifugation showed similar LPS inactivation as LDL prepared by immunoapheresis. We conclude that the inhibition of LPS-induced monocyte activation by human serum is dependent to a large extent on the LDL fraction. LDLs were demonstrated to inhibit LPS from inducing interleukin-1 release by human monocytes.

SUMMARY: In patients with pathologically altered erythrocytes, red blood cell exchange is a very efficient therapeutic measure without important side effects. With increasing migration more patients with e.g. severe malaria or sickle cell anemia have to be treated. In minor or bidirectional ABO-mismatched stem cell transplantations after reduced intensity conditioning, hemolysis can be prevented by prophylactic erythrocytapheresis. Other rare indications for red blood cell exchange are advanced erythropoietic protoporphyria and babesiosis. Sickle cell anemia can be treated with hydroxyurea. Transfusions are administered when necessary, but this results in iron overload in the long term. An expensive but safe and very efficient treatment alternative is red blood cell exchange. In cases with stroke, acute chest syndrome and other severe complications, erythrocytapheresis reproducibly breaks the vicious circle of sickling and increasing oxygen deficiency. At the same time one can aim at an exact end hematocrit. In severe malaria, erythrocytapheresis both reduces parasite load to the designated extent and reconstitutes reduced oxygen transport capacity without serious adverse effects. Here we describe our experience of erythrocytapheresis in long-term prophylaxis of complications in sickle cell anemia and sickle cell thalassemia patients. The documentation of improved iron balance was carried out by liver susceptometry.

CERN’s Large Hadron Collider (LHC) [1][2] will be supplied with protons from the injector chain Linac2-PS Booster (PSB)-PS-SPS (Fig. 1). The required transverse beam brilliance (intensity/emittance) is almost twice that of current PS beams and the LHC bunch spacing of 25 ns must be impressed on the beam before its transfer to the SPS. The scheme involves new RF harmonics in the PSB and the PS, an increase of the PSB energy, and two-batch filling of the PS. After a successful test of the main ingredients, a project for converting the PS complex was launched in 1994. Major additions are (i) h=1 RF systems in the PSB, (ii) upgrading of the PSB main magnet supply from 1 to 1.4 GeV operation, (iii) new magnets, septa, power supplies, kicker pulsers for the PSB-PS beam transfer, (iv) 40 and 80 MHz systems in the PS, (v) beam profile measurement devices with improved resolution. A significant part of the effort is being provided by TRIUMF under the Canada-CERN co-operation agreement on the LHC.

Under antidepressive treatment with amitryptiline (100 mg/d) a 71-year old woman developed delirious symptoms, hyponatremia and a grand mal seizure followed by cardiovascular arrest. A few month later she ingested 48 mg reboxetine with suicidal intent. Overdosing of reboxetine, a selective noradrenaline re-uptake inhibitor, proceeded without complications.

Elevated plasma lipoprotein (a) (Lp[a]) and cardiac events show a modest but significant association in various clinical studies. However, the influence of high Lp(a) on the gene expression in blood monocytes as a major cell involved in atherogenesis is poorly described. To identify genes influenced by elevated serum Lp(a), the gene expression was analyzed on a complementary DNA microarray comparing monocytes from a patient with isolated Lp(a) hyperlipidemia and coronary heart disease with monocytes from a healthy blood donor with low Lp(a). By using this approach, numerous genes were found differentially expressed in patient-versus-control monocytes. Verification of these candidates by Northern blot analysis or semiquantitative polymerase chain reaction in monocytes from additional patients with Lp(a) hyperlipidemia and healthy blood donors with elevated Lp(a) confirmed a significant induction of plasminogen activator inhibitor type 2 (PAI-2) messenger RNA (mRNA) in monocytes from male, but not from female, individuals with high Lp(a), indicating that this observation is gender specific. This led also to increased intracellular and secreted PAI-2 protein in monocytes from male probands with Lp(a) hyperlipidemia. Plasminogen activator inhibitor type 1 (PAI-1) mRNA was found suppressed only in the patients′ monocytes and not in healthy probands with high Lp(a) levels. Purified Lp(a) induced PAI-2 mRNA and protein and reduced PAI-1 expression in monocytes isolated from various controls. The finding that PAI-2 is elevated in monocytes from male patients with isolated Lp(a) hyperlipidemia and male healthy probands with high Lp(a) and that purified Lp(a) up-regulates PAI-2 in control monocytes in vitro indicate a direct, but gender-specific, effect of Lp(a) for the induction of PAI-2 expression.

The absorption of 239 MeV positive pions on $^{3}\mathrm{He}$, $^{4}\mathrm{He}$, N, and Ar is studied. A strong enhancement is seen in the differential cross sections in the kinematic region associated with free $\ensuremath{\pi}\ensuremath{-}p$ scattering. This enhancement is interpreted as a clear signature of initial state interactions in the absorption of pions on nuclei.

Physicians educate their patients by direct teaching and by serving as a role model. Through the use of questionnaires, we evaluated the degree to which physicians in West Virginia participate in these activities. Thirty-five percent of the 2,404 licensed physicians in the state returned completed questionnaires. Although 90% prescribed appropriate diets and recommended exercise for their patients, the physicians who responded were often less likely to follow their own advice. Twenty percent of the male physicians and 13% of the female doctors were obese; 30% had LDL cholesterol levels over 130 mg./dl.; 13% had HDL cholesterol values of less than 35 mg./dl.; and 8% had triglycerides over 250 mg./dl. Participation in regular exercise (30 minutes three times per week) was reported by 48% of the male physicians and 47% of the female physicians. Eight percent of the men were smokers, as were 1.9% of the females. These results suggest that the role model aspect of patient education may need to be improved among some West Virginia physicians. It is an inexpensive method of directing attention to lifestyle in order to decrease preventable disorders such as coronary artery disease, obesity, diabetes, and hypertension.

Heart disease is a significant problem in women. Age, smoking, and hyperlipidemia are potent risk factors, as is the presence of diabetes. Hypertension is less of a risk factor in women than men. Diagnosis of coronary artery disease is most difficult in women, especially using non-invasive techniques, because of a lower prevalence of disease. Thrombolytic therapy may be associated with more bleeding in older, smaller women. Angioplasty and surgical bypass may be more difficult because of smaller coronary artery size in women. Exercise, aspirin, and estrogens appear to decrease the incidence and mortality of heart disease in women, but concern has been raised that the use of resources for the study, prevention and treatment of heart disease has a gender bias, with men receiving more than their fair share.

Patients with non-insulin-dependent diabetes are at greatly increased risk for coronary artery disease. Although exercise training has been shown to decrease risk factors, the presence of obesity, older age, and a sedentary lifestyle make a high-intensity exercise program an unrealistic choice of therapy. Therefore, we examined the effect of a low-to-moderate-intensity (mean 69 per cent of maximal heart rate) walking program on lipids, glucose, insulin, glycosylated hemoglobin and cardiovascular fitness. Nine women and seven men, mean age 56, were randomly assigned to a control or an exercise group which exercised three times per week for two months. Supervised exercise sessions consisted of 40-45 minutes of walking and/or slow jogging. Subjects continued on their usual diets. The trained group showed a significant improvement in VO2max from 1.65 to 1.95 L/min. Resting systolic blood pressure decreased from 141 to 130 mm Hg after training, and resting heart rate decreased from 88 to 81. Glycosylated hemoglobin decreased in the exercise group in seven or eight subjects and in only two of eight controls. Triglycerides decreased in the exercise group from 285 to 223 mg/dl. Body weight, total and HDL cholesterol, glucose, and insulin did not change in either group. These data indicate that a low-to-moderate level of aerobic training, independent of dietary changes, is an effective and feasible method of improving cardiovascular risk factors: physical fitness, systolic blood pressure, plasma triglycerides, and glycemic control in non-insulin-dependent diabetic subjects.

Forty-five men (18-35 years) trained three times a week for eight weeks to determine the effects of four constant-resistant weight training programmes on muscular strength, endurance, body composition and cardiovascular functioning. Subjects were randomly assigned to one of four programmes: Endurance (2 sets of 15 repetition maximum [RM]); Explosive (1 set of 15 RM); Strength 1 (3 sets of 6 RM); Strength 2 (1 set of 10 RM twice weekly and 1 set of 3 RM once weekly). All groups showed significant increases in elbow and shoulder flexion strength with elbow extension strength improved in the Explosive, Strength 2 and Endurance groups. Shoulder extension strength improved the Endurance group and in the Strength 2 group. Maximum oxygen uptake (L/min) and (ml X kg-1 min-1) improved significantly in the Endurance and Strength 2 groups. Lean body weight increased significantly in all groups except the Strength 1 group, but there was no change in % fat for any group. Due to a high drop out rate (55%) and injury related problems, the Explosive technique is not recommended. The Endurance and Strength 2 programmes were most effective for improving physiologic functioning, as assessed in this study.

The (${\ensuremath{\pi}}^{\ensuremath{-}},2n$) process has been studied in a kinematically complete experiment on three neighboring $1p$-shell nuclei. Distributions of excitation energy of the residual nuclei, of recoil momentum, of the angle between the emitted neutrons, and the angle between the sum and the difference of the neutron momenta have been measured. From the excitation spectra a striking analogy with ($p,2p$) data has been found in the region of $p$-shell nucleon removal. The possibility of $s$-shell nucleon removal has been investigated. The data are compared with theoretical predictions.

The energy, width and intensity of prompt nuclear gamma -rays following capture of pi /sup -/ at rest by /sup 9/Be, /sup 10/B, /sup 16/O, /sup 19/F, /sup 31/P, Ca and /sup 93/Nb were measured with a Ge (Li) detector. In most cases it was possible to identify the final nucleus from the energy of the observed gamma -ray. Using the measured Doppler broadening of gamma -rays from short-lived states, the vector sum momentum distribution of the emitted nucleons was calculated. From the measured gamma -ray intensities, isotopic yields were deduced corresponding to the removal of from 1 to 12 nucleons. The average number of removed nucleons changes from 3.0 to 5.5 as the target varies from /sup 16/O to /sup 40/Ca. A comparison was made with data from both spallation reactions and multi-nucleon pick up reactions. (40 refs).

Direct comparison of the pionic K-series X-ray transitions for 16O/18O and 6Li/7Li has been made and a new measurement of the same transitions in 3He has been performed.

The total K-X-ray yield Y K in pionic 3 He has been determined to (27 ± 7)% by measuring a ratio of 3.44 ± 0.29 for the simultaneously detected numbers of K-X-rays and deuterons emitted after pion absorption. Partial K-X-ray yields Y K d and Y K p corresponding to the dn- and pnn-absorption channels, respectively, have been measured by detecting coincidences between K-X-rays and deuterons or protons above 20 MeV, respectively resulting in Y K d =(49 ± 5)% and Y K p ( T p ⩾20 MeV) = (29 ± 4)%.

Experimental data for 3 He(π + , pp)p at T π =120 MeV in a kinematical region dominated by three-nucleon absorption, where all three protons have obtained an appreciable amount of energy, are analyzed by means of variables specifically sensitive to different reaction mechanisms. The data are compared with predictions for two-step mechanisms and a genuine three-nucleon absorption mechanism. No evidence is found for such two-step processes as scattering or charge exchange preceding a two-nucleon absorption or as two-nucleon absorption followed by “Hard FSI”. The results, however, agree with a genuine three-nucleon absorption process, consistent with the recently measured phase-space-like behavior of this process.

The reactions π −3 He → nnp and π −3 He → nd have been measured in a kinematically complete experiment with stopped pions. The results show strong preference for collinear events. About three quarters of all absorption processes occur as quasi-free absorption on np- or pp-pairs with a ratio of R = 10.1 ± 1.5. The remaining quarter shows energy sharing among all three nucleons and is located in the final-state interaction regions. Branching ratios for all observed final states are given.

The (${\ensuremath{\pi}}^{\ensuremath{-}}$,$2n$) reaction on $^{6}\mathrm{Li}$ and $^{7}\mathrm{Li}$ nuclei has been studied in a kinematically complete experiment. Distributions of excitation energy of residual nuclei, of recoil momentum, and of angle spanned by relative and c.m. momenta of emitted neutrons have been extracted. The reaction mechanism has been investigated through a comparison with theoretical predictions.

An sauber tangential geschnittenen Furnierstreifen einiger Holzarten wird die Quellung in der Tangentialrichtung untersucht. Bei sorgfaltig wasserfreiem Arbeiten nehmen in der Reihe der aliphatischen primaren Alkohole C1−C6 mit zunehmender C-Kette die Quellungsgeschwindigkeit und der Grad der konstanten Endquellung ab und erreichen beim Hexanol praktisch den Nullwert. Iso-Alkohole wirken schwacher quellend als Normalformen. Von den anderen untersuchten Quellungsmitteln erzielt Wasser die starkste Quellung uberhaupt, dann folgen 1,4-Dioxan und Glycerin.