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At least 361 records · Page 20Linked to original sources
PubMed1996

[The microclimate conditions of the environment for treating patients in hospital clinics and wards (a review)].

The problem of the microclimatic parameters of the environment in some clinics and hospital departments is discussed as well as their significance in the general therapeutic course. The impact of the air environment as a potent therapeutic factor is outlined. It is stated that the temperature regime in the rooms must be differentiated in accordance to the climatic conditions, seasons, patient's age, the nosologic group. Discussing the problem with regard to the balance "man-environment" it is outlined that the adaptive capabilities, which are narrowed and altered in the patient, can not compensate for the unfavourable conditions of the environment. The authors point at differentiated values of the microclimatic parameters for the rooms in some clinics and departments.

Health Facility Environment↗
PubMedDate not supplied

[The use of an artificial microclimate chamber in the treatment of patients with chronic obstructive lung diseases].

Halotherapy was used for sanatorium rehabilitation in 29 patients with chronic obstructive pulmonary diseases (chronic bronchitis and asthma). Significant positive effects of this method resulted in the improvement of the flow-volume parameters curve of lung function and in hypotensive effects on blood pressure. Halotherapy is recommended for use in patients suffering from chronic obstructive pulmonary diseases with hypertension or coronary heart disease.

Adult↗
PubMed1999

Leaf orientation and distribution in a Phaseolus vulgaris L. crop and their relation to light microclimate.

Changes in canopy structure parameters (leaflet orientation, leaflet inclination and leaf area index) were measured in crops of beans (Phaseolus vulgaris L.) in the field as the canopy developed between July and October. These changes were compared with the corresponding changes in seasonal light transmission. The beans showed clear heliotropic behaviour, with preferential orientation of leaflets towards the sun's beam, especially on sunny days. Nevertheless a significant proportion of the leaves pointed in other directions, with as much as 20% oriented towards the north. The highest proportion of leaf inclinations was in the range 30-40 degrees on cloudy days and between 40 degrees and 50 degrees on sunny days. Two methods were compared for assessing changes in light transmission: (a) the use of a Sunfleck Ceptometer and (b) the use of continuous records obtained with sensors installed in the canopy. Over the growth period studied, the total of the leaf plus stem area indices (L(S)) increased from 0.26 to 5.2 with the transmission coefficient (tau) for photosynthetic photon flux density (PPFD), obtained using the Ceptometer, correspondingly decreasing from 0.72 to 0.05, and the canopy extinction coefficient decreasing from 1.4 to 0.62. The continuous records of light transmission gave generally similar estimates of tau. Some contrasting leaf angle distribution functions were compared for estimation of L(S) from the light measurements. The best leaf angle function to predict L(S) from the observed light transmission was a conical function corrected by the degree of heliotropism.

Journal Article↗
PubMed1988

Na+-dependent elevation of the acidic cell surface pH (microclimate pH) of rat jejunal villus cells induced by cyclic nucleotides and phorbol ester: possible mediators of the regulation of the Na+/H+ antiporter.

The effects of cyclic nucleotides and phorbol ester on the acidic cell surface pH of rat jejunal villi were studied by using single-barrelled pH-sensitive microelectrodes. Addition of dibutyryl cAMP (1 mM) to the mucosal bathing solution caused an elevation of the cell surface pH from 6.19 +/- 0.04 (n = 12 measurements from three animals) to 6.53 +/- 0.03 (12) in the presence of Na+ in the medium. However, dibutyryl cAMP had no significant effect in the absence of Na+ and presence of 1 mM amiloride. Dibutyryl cGMP (1 mM) also had an Na+-dependent inhibitory effect on the cell surface pH. A phorbol ester, phorbol 12-myristate 13-acetate, caused an elevation of the cell surface pH only in the presence of Na+ from 6.14 +/- 0.07 (12) to 6.46 +/- 0.08 (12). Phorbol and phorbol 13-acetate, which do not stimulate protein kinase C, were without significant effects. These results suggest that increased levels of the intracellular cyclic nucleotides and activation of protein kinase C raise the acidic cell surface pH by inhibiting the activity of the brush-border Na+/H+ antiporter in the rat jejunal villus cells.

Amiloride↗
PubMed1992

A preliminary study of the effect of microclimate on third-stage larvae of Haemonchus contortus and Haemonchus placei on irrigated pasture.

Assessments were made on the influence of several microclimatic variables on the availability of third-stage larvae of Haemonchus contortus and Haemonchus placei on four strata of irrigated Kikuyu pasture. Three replicates of these pasture samples were collected on 18 sample days over 12 months and the log10 mean counts of the larvae recovered were analysed by a step-wise regression model. Predictors for the log counts of the four strata for the two nematode species included relative humidity, illumination, air temperature and windspeed. The effect of air temperature on larvae of both Haemonchus species was similar; as air temperature increased, the number of larvae on pasture increased. The inverse was true for windspeed; as windspeed increased larval counts decreased. For H. contortus, relative humidity increased as the number of larvae increased on all strata except upper herbage. The R2 values ranged from 0.11 to 0.21 for H. contortus and from 0.04 to 0.12 for H. placei. Under the conditions of this study, only 21% of the effect on H. contortus and 12% on H. placei third-stage larvae on pasture can be explained by microclimatic conditions.

Animals↗
PubMed1988

The effect of heat-stable Escherichia coli enterotoxin, theophylline and forskolin on cyclic nucleotide levels and mucosal surface (acid microclimate) pH in rat proximal jejunum in vivo.

The normally acidic mucosal surface pH of 6.24 +/- 0.02(30) in rat proximal jejunum in vivo is effectively neutralised by 30 min exposure to heat-stable Escherichia coli (STa) enterotoxin (14 micrograms/ml) to 6.80 +/- 0.07 (n = 5) or to a forskolin/theophylline combination (1 mM:20 mM) to 7.10 +/- 0.07(7) while perfusion with Krebs-phosphate buffer alone without glucose left the mucosal surface pH unchanged at a pH of 6.21 +/- 0.02(9). Forskolin alone had no effect, and 20 mM theophylline moderately elevated the surface pH to 6.52 +/- 0.03(5). Theophylline, forskolin and their combination all elevated cAMP levels per mg tissue DNA above control values while STa enterotoxin was without effect. In contrast, all agents elevated cGMP levels per mg tissue DNA above control levels. These findings indicate that surface pH is only moderately affected by changes in cAMP levels and is affected to a much greater extent by altered cGMP levels.

Animals↗
PubMed2005

Varations in maize pollen emission and deposition in relation to microclimate.

The coexistence of genetically modified (GM) crops with conventional crops has become a subject of debate and inquiry. Maize (Zea mays L.) is one of the most cultivated crop plants in the world and there is a need to assess the risks of cross-pollination. Concentration and deposition rate downwind from different-sized maize crops were measured during three flowering seasons, together with micrometeorological conditions in the surrounding environment. Pollen release started once the air vapor pressure deficit (VPD) increases above 0.2 to 0.5 kPa. Moreover, the dynamics of release was correlated with the dynamics of VPD surrounding the tassels. Horizontal deposition appeared to follow a power law over short distance downwind from the source, and the dispersal distance increased with the source canopy height and the roughness length of the downwind canopy. This work also provides a data set containing both pollen measurements and contrasting weather conditions to validate dispersal models and further investigate maize pollen dispersal processes.

Air Pressure↗
PubMed1998

Air movement and the thermal microclimates observed in poultry lairages.

1. The thermal environment experienced by broilers during transport and a 4 h lairage period were recorded for 8 loads of birds to 2 processing plants under summer and winter conditions. 2. During the transport period the thermal environment was considered not to have been a significant challenge to bird welfare. 3. During the lairage period, over all 8 d, external ambient temperatures were in the range 4 degrees to 15 degrees C during the winter trials and 12 degrees to 29 degrees C during the summer. Temperatures amongst the crated birds for this period were in the range 16 degrees to 29 degrees C and 20 degrees to 31 degrees C during the winter and summer trials respectively. 4. Air velocity measurements at bird level indicated air movement was of small magnitude (typically < 0.1 m/s) and of variable direction, despite the large air movements around the modules with speeds of over 1 m/s. 5. The potentially stressful thermal environments observed during lairage were achieved rapidly (< 1 h) after unloading. It is considered, therefore, that the minimisation of holding time alone is not a suitable control strategy. 6. The use of water-misting sprays as a control strategy in one lairage was observed to lower the temperature throughout the lairage but raised the humidity, which might offset the temperature advantage to the birds' thermoregulatory ability. 7. More closely controlled environments for broiler lairage facilities are suggested, with further work to increase air movement at bird level.

Air Movements↗