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Notes: The roles of the autonomic nervous system and cardiac output on hypoxic pulmonary vasoconstriction were studied in 15 mongrel dogs anaesthetised with intravenous pentoharbitone (30 mg/kg) and the lungs mechanically ventilated to maintain normal arterial blood gases. After a hypoxic challenge in Group I (n =6) and Group II (n =3) animals, autonomic denervation was achieved by total spinal block with tetracaine (20 mg) injected into the cisterna magna. Group I animals received a large volume of intravenous fluid (80 ml/kg normal saline) before the block while Group II animals were given minimum fluid. When Group I animals were exposed to 10% inspired oxygen, mean pulmonary arterial pressure increased by 88 and by 72% before and after the block, respectively. The cardiac output increased by 27% with hypoxia before the block while it did not change significantly with hypoxia after the block. The pulmonary vascular resistance increased by 65 and by 152% with hypoxia before and after the block. Group II animals were also exposed to 10% inspired oxygen. They showed a similar response to Group I animals before the block. However, after the block irreversible hypotension developed with hypoxia. In Group III animals (n =6), the same anaesthesia and hypoxic challenge protocol was used. Immediately after measurements at 10 minutes of hypoxia, the inferior vena cava was constricted to reduce the cardiac output to the control level and another set of measurements were made. The cardiac output increased by 30% with hypoxia and then was reduced to the control level with vena caval constriction. The mean pulmonary arterial pressure increased by 125% with hypoxia and then it decreased slightly with the inferior vena cava constriction. The pulmonary vascular resistance increased by 95% with hypoxia and then it further increased by 28% with the vena caval constriction. These results suggest that sympathectomy accentuates rather than attenuates the hypoxic pulmonary vasoconstriction and that an increase in cardiac output counteracts hypoxic pulmonary vasoconstriction. The results also suggest that adequate intravascular volume and oxygenation are extremely important for maintaining homeostasis when reflex sympathetic stimulation to the cardiovascular system has been eliminated.

Notes: Clarithromycin is one of the macrolide antibiotics used for cutaneous and respiratory system infections. Only a few cases of adverse cutaneous reactions to this drug have been reported. Here we report a rare case of clarithromycin-induced fixed drug eruption which could be reproduced by a peroral provocation test, whereas patch tests on both unaffected and residual pigmented skin yielded negative results. All cutaneous lesions that recurred due to the challenge test developed the same pigmentation after a short course of intravenous corticosteroid.

Notes: Summary The calibration factors of the Davos-type pyrradiometer were investigated experimentally and theoretically for both long-wave and short-wave radiation. The apparatus which was developed for calibrating pyrradiometers for long-wave radiation is illustrated. The calibration for long-wave radiation was made over melting ice and a heated water surface of 40°C with an instrument temperature of 20°C. The following characteristics were investigated: cosine and azimuth errors; the efficiency of the thermopile; the effects of ventilation, thermal stability of the air in the hemisphere and the overheating of the polyethylene hemisphere. The results are summarized in the form of ratios of calibration factors for long-wave radiation to those for short-wave radiation under various conditions. Improved methods of installing pyrradiometers and of evaluating the field data are recommended.

Notes: Abstract. Total body bone mineral content (BMCTB in g) and density (BMDTB in g/cm2) and body composition were measured in 1006 healthy Japanese women aged 20–79 years using dual X-ray absorptiometry. Peak BMDTB was 1.11 ± 0.05 g/cm2 in women 20–49 years, and mean BMDTB was 1.019 g/cm2 in the 6th decade, 0.956 g/cm2 in the 7th decade, and 0.900 g/cm2 in the 8th decade. BMDTB declined by 0.007 g/cm2/year in women after age 50. This age-related decline in BMD showed a similar pattern to that seen for the lumbar spine and femoral neck, but the actual rate of loss was lower for BMDTB than for these other measurement sites. There was no significant difference between a eumenorrheic premenopausal group and a group with irregular menses. BMCTB and BMDTB were associated with body build, lean tissue mass, and fat mass (r = 0.29 ∼ 0.65 and 0.26 ∼ 0.41, respectively). Bone mass and density decreased significantly in older women of all body builds. Premenopausal Japanese women had a 5% lower BMDTB than U.S. and European whites, but the difference was several times greater in postmenopausal than in premenopausal women.

Notes: Abstract  Annual cycles of monthly albedos simulated with a general circulation model (GCM) are compared with surface observations. The data observed at 35 stations are retrieved from the Global Energy Balance Archive (GEBA) and drawn from the soil moisture and meteorological observations in the former Soviet Union. The model data are obtained with the ECHAM4 GCM in a ten-year simulation of the present-day climate at T106 resolution. The model calculated albedo values are modified before they are compared with the surface observations: They are interpolated to the stations and adjusted to account for altitude differences and fractional forest area. During the snow-free period, the model underestimates the albedo by up to 0.05 at the stations (with values between 0.2 and 0.25 measured over short grass) because the albedo for grassland is too low in the model. During the period with seasonal snow cover, the model underestimates the albedo by up to 0.2 at stations in Russia, Scandinavia and Canada, which experience severe winters. This underestimation is due to an oversimplified parameterization of the snow covered grid fraction and an inadequate linear relation between snow albedo and temperature. The derivative of albedo with respect to the forest fraction implemented in ECHAM is in line with the observations, although a small overestimation of the model’s gradient has been detected.

Notes: Abstract  A comprehensive dataset of direct observations is used to assess the representation of surface and atmospheric radiation budgets in general circulation models (GCMs). Based on combined measurements of surface and collocated top-of-the-atmosphere fluxes at more than 700 sites, a lack of absorption of solar radiation within the atmosphere is identified in the ECHAM3 GCM, indicating that the shortwave atmospheric absorption calculated in the current generation of GCMs, typically between 60 and 70 Wm-2, is too low by 10–20 Wm-2. The surface and atmospheric radiation budgets of a new version of the Max-Planck Institute GCM, the ECHAM4, differ considerably from other GCMs in both short- and longwave ranges. The amount of solar radiation absorbed in the atmosphere (90 Wm-2) is substantially larger than typically found in current GCMs, resulting in a lower absorption at the surface (147 Wm-2). It is shown that this revised disposition of solar energy within the climate system generally reduces the biases compared to the observational estimates of surface and atmospheric absorption. The enhanced shortwave absorption in the ECHAM4 atmosphere is due to an increase in both simulated clear-sky and cloud absorption compared to ECHAM3. The increased absorption in the cloud-free atmosphere is related to an enhanced absorption of water vapor, and is supported in stand-alone comparisons of the radiation scheme with synchronous observations. The increased cloud absorption, on the other hand, is shown to be predominantly spurious due to the coarse spectral resolution of the ECHAM4 radiation code, thus providing no physical explanation for the “anomalous cloud absorption” phenomenon. Quantitatively, however, an additional increase of atmospheric absorption due to clouds as in ECHAM4 is, at least at low latitudes, not in conflict with the observational estimates, though this does not rule out the possibility that other effects, such as highly absorbing aerosols, could equally contribute to close the gap between models and observations. At higher latitudes, however, the increased cloud absorption is not supported by the observational dataset. Overall, this study points out that not only the clouds, but also the cloud-free atmosphere might be responsible for the discrepancies between observational and simulated estimates of shortwave atmospheric absorption. The smaller absorption of solar radiation at the surface in ECHAM4 is compensated by an increased downward longwave flux (344 Wm-2), which is larger than in other GCMs. The enhanced downward longwave flux is supported by surface measurements and by a stand-alone validation of the radiation scheme for clear-sky conditions. The enhanced flux also ensures that a sufficient amount of energy is available at the surface to maintain a realistic intensity of the global hydrological cycle. In contrast, a one-handed revision of only the shortwave radiation budget to account for the increased shortwave absorption in GCM atmospheres may induce a global hydrological cycle that is too weak.

Notes: Abstract The velocity (SOS), attenuation slope (BUA) and stiffness index in the os calcis were measured using the ‘Achilles’ ultrasound bone densitometer (Lunar, Madison, WI). We evaluated the basic attributes of this ultrasound bone densitometer, and showed the age-related changes in ultrasound values in normal Japanese women. The precision was measured in vivo on ten occasions over a 2-week period in 5 subjects. The short-term precision errors (CVs) in vivo were 0.6% for stiffness index, 0.3% for SOS and 1.0% for BUA. Spine, femur neck and total body BMD using dual X-ray absorptiometry (DXA) were highly correlated with stiffness index (r=0.80, 0.77 and 0.78, respectively) in 194 subjects. Ultrasound values for patients with osteoporosis were significantly lower than those for the normal controls. TheZ-score compared with young normals was significantly higher for spine bone mineral density (−4.4) than for stiffness index (−3.5); BUA and SOS gave significantly lowerZ-scores −2.9 and −3.0, respectively). Ultrasound values were also lower compared with age-matched normal controls. TheZ-score for stiffness index (−2.1) was significantly superior to that for either SOS or BUA (−1.5). Age-related change in ultrasound values was evaluated in 842 normal women. There was a decline in stiffness index of about 24% from the values in young adulthood to those of women in their seventies, about 75% of which occurred from age 44–49 years onward. These findings seem to indicate that the menopause affected the change in ultrasound values. In conclusion, ultrasound bone densitometry may not be as useful as DXA of the spine for screening for osteoporosis, since theZ-score for DXA is excellent. However, ultrasound bone densitometry appears potentially to be applicable to problems in the diagnosis and management of osteoporosis when used in association with DXA.

Notes: Summary Simulated temperature and precipitation changes over western Europe for a scenario of doubled atmospheric concentrations of CO2 are presented. The simulations are performed using a Limited Area Model LAM (RegCM2) nested into a General Circulation Model (ECHAM3). Both model components are operated at very high spatial resolutions — approximately 120 km for the GCM and 20 km for the LAM; the LAM domain encompasses a region of 1100 × 1100 km squared. Climatologies for five January and five July periods have been simulated. Average surface (2 m) temperatures are found to increase by 1.4 K in winter (January) and 3.9 K in summer (July); this latter figure is, however, largely dependent on a positive bias in the summer temperature fields of the driving GCM. Average precipitation changes are generally small in absolute values, but exhibit considerable spatial variability. Large precipitation amounts are seen to be shifted towards higher elevations with a corresponding reduction in the ‘upwind’ areas. The results are discussed taking into account the ‘predictive skill’ of the modelling system, which is derived from comparing the simulated present day temperature and precipitation fields to the corresponding climatological information. A method is introduced to assess the reliability of climate scenario predictions — such as those discussed here — on the basis of this predictive skill.