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At least 613 records · Page 34Linked to original sources
PubMed1999

Indoor air quality at the Correr Museum, Venice, Italy.

Two multidisciplinary field surveys, one in winter and the other in summer have monitored the indoor microclimate, air pollution, deposition and origin of the suspended particulate matter and microorganisms of the Correr Museum, Venice. In addition, this study was focused to identify the problems caused by the heating and air conditioning system (HAC) and the effects due to the presence of carpets. Heating and air conditioning systems (HACs), when chiefly designed for human welfare, are not suitable for conservation and can cause dangerous temperature and humidity fluctuations. Improvements at the Correr Museum have been achieved with the assistance of environmental monitoring. The carpet has a negative influence as it retains particles and bacteria which are resuspended each time people walk on it. The indoor/outdoor pollutants ratio is greater in the summertime, when doors and windows are more frequently open to allow for better ventilation, illustrating that this ratio is mainly governed by the free exchange of the air masses. The chemical composition, size and origin of the suspended particulate matter have been identified, as well as the bacteria potentially dangerous to the paintings. Some general suggestions for improving indoor air quality are reported in the conclusions.

Aerosols↗
PubMed1999

Inorganic deterioration affecting the Altamira Cave, N Spain: quantitative approach to wall-corrosion (solutional etching) processes induced by visitors.

In order to study the wall corrosion processes induced by visitors in the Altamira Cave (northern Spain), a multidisciplinary study was conducted in the cave. For a period of 1 year, a microclimate monitoring system, measuring the temperature, relative humidity, CO2 and 222Rn concentrations was operated. Host rock samples were collected as well as indoor and outdoor atmospheric particulate matter. These data are used for a quantitative assessment of the wall corrosion processes. The presence of visitors was found to enhance the corrosion processes up to 78 times in comparison with the natural processes. Outdoor air pollution did not have a significant affect.

Air Pollution↗
PubMed1984

The relationship between the size of Lymnaea truncatula naturally infected with Fasciola hepatica and the intensity and maturity of the redial infection.

Of the 2,652 Lymnaea truncatula collected from sites in Cumbria and Gwynedd during 1973-75, when the prevalence of fascioliasis in the primary host was low and declining, only 123 were infected with Fasciola hepatica. Dissection of these snails revealed that the proportion infected, the mean redial burden and the proportion of mature rediae in each snail increased with shell length. The results are compared with a similar data set acquired when the prevalence of infection in both the primary and intermediate hosts was uncharacteristically high. Although the results are qualitatively similar, there are important quantitative differences. The mean redial burden of infected snails at times of high disease prevalence was generally twice as high as that reported in the present study. It is suggested that differences in habitat microclimate could not account entirely for the observed differences in redial burden and the role of multiple miracidial infection is discussed.

Animals↗
PubMed2001

Genetic evidence for adaptation-driven incipient speciation of Drosophila melanogaster along a microclimatic contrast in "Evolution Canyon," Israel.

Substantial genetic differentiation, as great as among species, exists between populations of Drosophila melanogaster inhabiting opposite slopes of a small canyon. Previous work has shown that prezygotic sexual isolation and numerous differences in stress-related phenotypes have evolved between D. melanogaster populations in "Evolution Canyon," Israel, in which slopes 100-400 m apart differ dramatically in aridity, solar radiation, and associated vegetation. Because the canyon's width is well within flies' dispersal capabilities, we examined genetic changes associated with local adaptation and incipient speciation in the absence of geographical isolation. Here we report remarkable genetic differentiation of microsatellites and divergence in the regulatory region of hsp70Ba which encodes the major inducible heat shock protein of Drosophila, in the two populations. Additionally, an analysis of microsatellites suggests a limited exchange of migrants and lack of recent population bottlenecks. We hypothesize that adaptation to the contrasting microclimates overwhelms gene flow and is responsible for the genetic and phenotypic divergence between the populations.

Adaptation, Physiological↗
PubMed1995

Halotherapy for treatment of respiratory diseases.

This work elucidates the questions upon the development of a new drug-free method of a respiratory diseases treatment. Halotherapy (HT)--is mode of treatment in a controlled air medium which simulates a natural salt cave microclimate. The main curative factor is dry sodium chloride aerosol with particles of 2 to 5 mkm in size. Particles density (0.5-9 mg/m3) varies with the type of the disease. Other factors are comfortable temperature- humidity regime, the hypobacterial and allergen-free air environment saturated with aeroions. The effect of HT was evaluated in 124 patients (pts) with various types of respiratory diseases. The control group of 15 pts received placebo. HT course consisted of 10-20 daily procedures of 1 hour. HT resulted in improvements of clinical state in the most of patients. The positive dynamics of flow-volume loop parameters and decrease of bronchial resistance measured by bodyplethysmography were observed. The changes in control group parameters after HT were not statistically significant. The specificity of this method is the low concentration and gradual administration of dry sodium chloride aerosol. Data on healing mechanisms of a specific airdispersive environment of sodium chloride while while treatment the respiratory diseases are discussed.

Adolescent↗
PubMed2005

Spatial and temporal dynamics of potato tuberworm (Lepidoptera: Gelechiidae) infestation in field-stored potatoes.

The potato tuberworm, Phthorimaea operculella (Zeller), is a major pest of potatoes in fields and traditional storage. A common method of nonrefrigerated storage is to pile potatoes in straw-covered heaps in the field. Tubers may be stored up to 3-4 mo in this manner, until the next harvest. We studied the dynamics of potato tuber moth infestation associated with such field storage in a 12-wk experiment in Israel. We set up six potato heaps, and sampled them for potato tuber moth at different locations at weekly intervals. Potato tuber moth infestation was significantly higher at the perimeter of the heaps than at their center, but it did not differ between bottom, mid-height, and top of the heaps. The proportion of potato tuber moth-infested potato tubers increased from 10 to 65% over the course of the experiment, and the mean number of potato tuber moth larvae per tuber increased from 0.25 to 2.50. Potato tuberworm populations increased sharply after 3, 6, and 9 wk of study, possibly corresponding to successive generations that developed within the heaps. This interpretation is supported by calculations of potato tuberworm generation length based on temperature data. Catches in pheromone traps that were placed near the heaps were not correlated (spatially and temporally) with potato tuberworm densities within heaps, hinting that migration among heaps did not considerably affect within-heap population dynamics. Potato tuberworm levels were not correlated with ambient temperatures, perhaps because of the warm, humid, and constant microclimate within the heaps. We discuss the significance of our findings for control efforts of the potato tuberworm.

Animals↗
PubMed1998

Water balance of Dermatophagoides pteronyssinus (Acari: Pyroglyphidae) maintained by brief daily spells of elevated air humidity.

A facility was constructed to expose cultured Dermatophagoides pteronyssinus (Trouessart) to 24-h cycles of changing relative humidity; low humidity was interrupted every day by a period of high humidity. The temperature was kept at 16 degrees C, a common temperature on the ground floor of Dutch houses. Partially dehydrated mites were exposed to various humidity regimes in the absence of food and liquid water. Some mites gained weight when moist air was given for only 1.5 h every day. In the presence of food, egg production was recorded when moist air was given for at least 3 h daily, whereas the average relative humidity was quite low and less than the critical equilibrium humidity of D. pteronyssinus. Brief spells of elevated humidity allowed populations to survive much longer in a microclimate that was otherwise too dry, and may be decisive for survival during the winter months. We found that average relative humidity was misleading as an indicator of mite survival and growth conditions.

Acari↗
PubMed2005

Effects of microclimatic changes caused by land use and land cover on duration of gonotrophic cycles of Anopheles gambiae (Diptera: Culicidae) in western Kenya highlands.

Studies were carried out at a malaria epidemic-prone highland site in western Kenya to determine the effects of deforestation-caused microclimate change on the duration of the gonotrophic cycle of the malaria vector Anopheles gambiae Giles. Gonotrophic cycle duration was measured using field-collected F1 A. gambiae females. Average ambient temperature in the deforested area of Kakamega (elevation 1,430-1,580 m above sea level), western Kenya, was 0.5 degrees C higher than that of the forested area over a 10-mo period. During the dry season, deforested areas showed an increased mean indoor temperature of 1.8 degrees C, and a shortened duration of the mosquitoes' first and second gonotrophic cycles, by 1.7 d (59%) and 0.9 d (43%). During the rainy season, the average indoor temperature of houses located in the deforested area was 1.2 degrees C higher than in houses in the forested area. The duration of the first and second gonotrophic cycles was shortened by 1.5 d (17%) and 1.4 d (27%), respectively, in the deforested highland site. A shorter mosquito gonotrophic cycle implies increased daily biting frequency and thus increased vectorial capacity. Together with evidence that deforestation reduced A. gambiae larva-to-adult developmental time and increased larval and adult survivorship, this study suggests that deforestation can further enhance malaria transmission potential in the highlands through increased indoor temperature and shortened gonotrophic cycle durations of A. gambiae mosquitoes.

Animals↗
PubMed2005

Phylloclimate or the climate perceived by individual plant organs: what is it? How to model it? What for?

This review introduces the emergence of a new research topic, phylloclimate, located at the crossroads between ecophysiology and canopy microclimate research. Phylloclimate corresponds to the physical environment actually perceived by each individual aerial organ of a plant population, and is described by physical variables such as spectral irradiance, temperature, on-leaf water and features of around-organ air (wind speed, temperature, humidity, etc.). Knowing the actual climate in which plant organs grow may enable advances in the understanding of plant-environment interactions, as knowing surface temperature instead of air temperature enabled advances in the study of canopy development. Characterizing phylloclimate variables, using experimental work or modeling, raises many questions such as the choice of suitable space- and time-scale as well as the ability to individualize plant organs within a canopy. This is of particular importance when aiming to link phylloclimate and function-structure plant models. Finally, recent trends and challenging questions in phylloclimate research are discussed, as well as the possible applications of phylloclimate results.

Ecosystem↗
PubMed2006

An overview of challenges in modeling heat and mass transfer for living on Mars.

Engineering a life-support system for living on Mars requires the modeling of heat and mass transfer. This report describes the analysis of heat and mass transfer phenomena in a greenhouse dome, which is being designed as a pressurized life-support system for agricultural production on Mars. In this Martian greenhouse, solar energy will be converted into chemical energy in plant biomass. Agricultural products will be harvested for food and plant cultivation, and waste materials will be processed in a composting microbial ecosystem. Transpired water from plants will be condensed and recycled. In our thermal design and analysis for the Martian greenhouse, we addressed the question of whether temperature and pressure would be maintained in the appropriate range for humans as well as plants. Energy flow and material circulation should be controlled to provide an artificial ecological system on Mars. In our analysis, we assumed that the greenhouse would be maintained at a subatmospheric pressure under 1/3-G gravitational force with 1/2 solar light intensity on Earth. Convection of atmospheric gases will be induced inside the greenhouse, primarily by heating from sunlight. Microclimate (thermal and gas species structure) could be generated locally around plant bodies, which would affect gas transport. Potential effects of those environmental factors are discussed on the phenomena including plant growth and plant physiology and focusing on transport processes. Fire safety is a crucial issue and we evaluate its impact on the total gas pressure in the greenhouse dome.

Agriculture↗
PubMedDate not supplied

Design and development of an automated and non-contact sensing system for continuous monitoring of plant health and growth.

An automated system was designed and built to continuously monitor plant health and growth in a controlled environment using a distributed system approach for operational control and data collection. The computer-controlled system consisted of a motorized turntable to present the plants to the stationary sensors and reduce microclimate variability among the plants. Major sensing capabilities of the system included machine vision, infrared thermometry, time domain reflectometry, and micro-lysimeters. The system also maintained precise growth-medium moisture levels through a computer-controlled drip irrigation system. The system was capable of collecting required data continuously to monitor and to evaluate the plant health and growth.

Automation↗
PubMed2003

Roost selection by Formosan leaf-nosed bats (Hipposideros armiger terasensis).

Patterns of roost use by Formosan leaf-nosed bats (Hipposideros armiger terasensis) were studied from November 1998 to April 2000. Structural characteristics, microclimates, and disturbance levels of 17 roosts used by H. a. terasensis and 15 roosts either used by other bat species (2) or not occupied by any bat species were compared. Roosts used by these bats were significantly larger in size and had greater areas covered by water compared to unused roosts. Entrances of active roosts were more likely to be east-west oriented. Hibernacula had lower entrances and ceilings than did roosts used only in summer. Higher temperatures were recorded in non-breeding roosts than in breeding roosts, but temperature gradients in these two types of roosts did not differ. In winter, hibernacula were warmer, and the temperature fluctuated less than in non-hibernacula. The relative humidities in summer roosts and hibernacula were nearly 100%. Disturbance levels were significantly higher in non-breeding roosts than in breeding roosts, and in non-hibernacula than in hibernacula. These results suggest that the Formosan leaf-nosed bats are selective of their roosts, but the pattern of their roost selection differs from those reported for bats of temperate regions. The reasons for such differences may be related to differences in body size, behavior, and reproductive strategy of the Formosan leaf-nosed bats living in a subtropical climate in Taiwan.

Animals↗
PubMed1998

Effects of two kinds of underwear on metabolic heat production during 60 min recovery after 30 min severe exercise in the cold.

The purpose of this study is to investigate the thermophysiological significance of hydrophilic and hydrophobic properties of underwear materials under the influences of profuse sweating produced during severe exercise in the cold. Two kinds of underwear were used: two layers of cotton underwear with two-piece long-sleeved shirt and full-trousers (C), and two layers of polypropylene underwear with two-piece long-sleeved shirt and full-trousers (P). In addition, the subject put on a two-piece ski suit of 100% polyester including 100% polyester padding. Eight adult females volunteered as subjects in this study. The test was performed in a climatic chamber at an ambient air temperature of 2 degrees C and an air velocity of 0.26 m.s-1. The subject exercised on a cycle ergometer at an intensity of 65% maximal oxygen uptake for 30 min and followed by 60 min recovery. The major findings are summarized as follows: 1) The fall of rectal temperature tended to be greater in P during the recovery. 2) The absolute humidity of innermost layer and middle layer was significantly higher in C than in P during the recovery, but the absolute humidity of middle layer and outermost layer was significantly higher in P than in C during the exercise. 3) Clothing microclimate temperature of innermost at back was significantly higher in C during the exercise and recovery. 4) Metabolic heat production for last 30 min during recovery was significantly higher in P. 5) The degree of skin wettedness sensation and sweating sensation for whole body was significantly higher in P during the exercise. It was concluded that the slower evaporation behavior by absorbing of underwear material in the clothing system has a beneficial influence on thermophysiological responses during severe exercise and its recovery in the cold, although the differences were very small.

Adult↗
PubMed2003

Effects of thermal underwear on thermal and subjective responses in winter.

This study was conducted to obtain basic data in improving the health of Koreans, saving energy and protecting environments. This study investigated the effects of wearing thermal underwear for keeping warm in the office in winter where temperature is not as low as affecting work efficiency, on thermoregulatory responses and subjective sensations. In order to create an environment where every subject feels the same thermal sensation, two experimental conditions were selected through preliminary experiments: wearing thermal underwear in 18 degrees C air (18-condition) and not wearing thermal underwear in 23 degrees C air (23-condition). Six healthy male students participated in this study as experiment subjects. Measurement items included rectal temperature (T(re)), skin temperature (T(sk)), clothing microclimate temperature (T(cm)), thermal sensation and thermal comfort. The results are as follows: (1) T(re) of all subjects was maintained constant at 37.1 degrees C under both conditions, indicating no significant differences. (2) (T)(sk) under the 18-condition and the 23-condition were 32.9 degrees C and 33.7 degrees C, respectively, indicating a significant level of difference (p<0.05). (3) Among local skin temperature, trunk part (forehead and abdomen) did not show significant differences. After 90-min exposure, the skin temperature of hands and feet under the 18-condition was significantly lower than that under the 23-condition (p<0.001). (4) More than 80% of all the respondents felt comfortable under both conditions. It was found (T)(sk) decreased due to a drop in the skin temperature of hands and feet, and the subjects felt cooler wearing only one layer of normal thermal underwear at 18 degrees C. Yet, the thermal comfort level, T(re) and T(cm) of chest part under the 18-condition were the same as those under the 23-condition. These results show that the same level of comfort, T(re) and T(cm) can be maintained as that of an environment about 5 degrees C higher in the office in winter, by wearing one layer of thermal underwear. In this regard, this study suggests that lowering indoor temperature by wearing thermal underwear in winter can contribute to saving energy and improving health.

Adult↗
PubMed1999

[The efficacy of subterranean therapy in the salt chamber of Kinga Spa in Wieliczka for patients suffering from allergic rhinitis].

42 patients (27 women and 15 men aged 14-65 years) suffering from atopic and non atopic rhinitis were submitted for 24 days to the subterraneo-therapy in salt chambers of Kinga Spa in Wieliczka during the exacerbation of their illness. 20 patients suffered from pollen or dust mites allergy and the next 22 patients from non atopic rhinitis with recurrent nasal polyposis. In the first week and at the end of the therapy rhinoscopy, peak nasal inspiratory flow and smell were evaluated as well as daily symptoms score was noted in each treated patient. The results of performed observations indicate that unrelatively to the type of the rhinitis: 1. the nasal symptoms (running nose, sneezing, block of the nose) resolved directly during the stay of the patient in the salt chamber but the more constant effect was visible with the time of the therapy. 2. an increase in the peak nasal expiratory flow was connected with the decrease of nasal mucosal edema, 3. the smell disturbances disappeared in the patients together with the decrease of mucosal edema. The observed changes seem to be connected with the influence of the salt chambers' microclimate on the cells osmolarity disturbances in the nasal mucosa provoked by the non infectious chronic inflammation.

Adolescent↗
PubMed2000

The different effects of black and white Vietnamese Aodai folk costumes on rectal temperature and heart rate in women walking intermittently in hot and sunny environment.

The present study was undertaken to investigate whether there is any difference in the rectal temperature and heart rate between women wearing black or white Aodai folk costume and walking intermittently in natural sunlight. The experiment was performed in the field outside buildings in Hanoi, Vietnam, between May and June, 1998. The only difference was in the colour (black or white) of clothing other physical characteristics, like materials, thickness, weight and so on, were nearly identical. Air temperature was around 39 degrees C, globe temperature around 52 degrees C and sun radiation reached 1010 W.m-2. Eight young female students (aged 20 years) participated in the experiment. They sat quietly on a chair inside the building for the first 30 min. Then they walked for 20 min at their ordinary walking speed in the sun, and rested for 10 min in the shade. This schedule was repeated three times. The main results are summarised as follows: (1) Rectal temperature was significantly lower in the black than in the white Aodai; (2) Clothing microclimate temperature at frontal chest level was also significantly lower in the black Aodai; (3) Heart rate was significantly lower in the black than in the white Aodai; (4) Clothing surface and inside temperatures measured at frontal chest level were significantly higher in the black than in the white Aodai. These results strongly suggest that the black Aodai could reduce heat strain more effectively than the white one. The physiological mechanism may result from more effective ventilation between skin and clothing in the black Aodai, due to higher temperature inside and outside this garment.

Adult↗
PubMed1999

[Hygienic appraisal on apartment houses in the western district of Beijing].

A survey on the essential factors of building hygiene of 12 apartment houses in the Western District of Beijing was presented. The site environment layout of rooms, illumination, ventilation, microclimate, indoor air quality, floor area per person, necessary equipped facilities etc, in the apartment, and its hygienic appraisal were assessed. The results and appraisal of the study showed that almost all the essential factors of building hygiene complied with the requirements of the national hygienic standards for air pollutants in indoors and in hotels. On the other hand, there existed some shortcomings, such as the gas appliance for heating water produced large amount of pollutants in the kitchen it there was no proper ventilation for it. Suggestions for their improvements were put forward. The appraisal is useful for improving the living conditions in apartment houses and also useful for the design and construction.

Air Pollution, Indoor↗