摘要:

To study the aerobiological processes directly, it is important to differentiate between fresh and older pollen grains. Different methods were tested for this purpose using birch (Betula) pollen. Simple general stains stained also dead grains. More specific histochemical techniques (nitro blue tetrazolium and isatin) stained a high percentage of the grains even after eight days, although most of the germination ability was lost already in 2–3 days. Of the methods tried, thein vitrogermination test was thus the most sensitive in differentiating between fresh and older pollen grains. To test the germination ability of airborne pollen it was collected by a suction pump on filters. Sectors of filters were incubated on a thin layer of agar on objective glasses in moist Petri dishes in +30°C for 24 hours. The germination ability was presumed to vary during the pollen season, but this was not found in this preliminary study. The diurnal variation in germination ability was clear. During or near diurnal peak concentrations the percentage of germination ability significantly higher than during diurnal minima and during intermediate concentrations.

ISSN:0017-3134    

DOI:10.1080/00173139109432003

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The possibility to apply diffusiophoresis and the Stefan flow effects in a new type of sampler was investigated. The advantages of the later are significant compared with other sampler desingns, since it gives representative samples that can subsequently analysed by the methods of optic and electron microscopy. The low particle deposition velocity keeps microorganisms intact, on the other hand, the small depence of the particles' deposition velocity upon their sizes makes the separation of the analyzed aerobiological objects impossible. As a result, the representativness of samples is secured. In this paper the sampler design is described and its working conditions (heat, hydrodynamic) are analyzed.

ISSN:0017-3134    

DOI:10.1080/00173139109432004

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Spores of fungi and actinomycetes are often aggregated, greatly affecting their aerodynamic behaviour with significance for both plant pathology and medicine. However, apart from experimental work with inorganic particles relative to industrial hygiene and lung deposition, the effects of aggregation on aerodynamic behaviour have been little studied. The available information is reviewed and methods are suggested for the study of microbial aggregates.

ISSN:0017-3134    

DOI:10.1080/00173139109432005

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Exposure to microorganisms, including thermophilic actinomycetes and fungal spores, and to airborne dust produced during compost production and mushroom picking may cause work-related respiratory symptoms. Previous studies have implicatedThermoactinomyces vulgarisandFaenia rectivirgula, the aetiological agents in farmer's lung disease, as causes of these symptoms but these species have been rare in aerobiological studies of mushroom farms. As part of a study of the respiratory health of the exposed workers, we carried out an aerobiological survey of all the stages of commercial mushroom production. Samples of viable airborne microorganisms were collected at a farm from eight locations on two occasions using Andersen cascade impactors. Large numbers of airborne thermophilic actinomycetes, yielding > 106colony-forming units (cfu) m−3air sampled, were associated with compost handling. These were predominantlyThermomonosporaspp., whileThermoactinomycesspp. andFaenia rectivirgulawere few. Because the compost was largely undisturbed, few airborne actinomycete spores were found in mushroom growing houses, but concentrations of fungal spores exceeded 105cfu m−3when mushrooms were being harvested. Most werePenicilliumspp. andAspergillus fumigatusbutPeziza ostracodermaandTrichodermaspp. were also isolated. Workers are thus exposed to a wide range of airborne microorganisms, but the role of many of these in mushroom workers' respiratory symptoms is not yet fully understood.

ISSN:0017-3134    

DOI:10.1080/00173139109432006

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Three different methods were used for the monitoring of airborne microorganisms: (1). Cultivation of microbes trapped in a single-stage biological impactor directly on a solid agar nutrient medium (meat-pepton agar, Sabouraud's agar, blood agar) in Petri dishes. The repeated yearly course of concentrations of cultivable organisms, or colony-forming units (CFU), was obtained by long-run measurements. (2) Aeresol was trapped by impact on membrane filters, and the microorganisms were cultivated by placing the filters on the agar media as above. (3) Direct microorganism counting in a fluorescence microscope; air was sampled in a four-stage impactor where the aerosol was trapped on microscope slides, and the microorganisms were subsequently stained with fluorescent dyes (fluorescein diacctate, 4;6-diamidino-2-phenylindole and, particular, ethidium bromide).

ISSN:0017-3134    

DOI:10.1080/00173139109432007

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Numbers of airborne microorganisms, fungi, Gram-negative bacteria, thermophilic microorganisms, endotoxins and dust have been monitored in resource recovery plants and composting plants. The work is still in progress, so this paper decribes only preliminary results. Only low levels (< 15 ng m−3) of endotoxins were found at all locations. Levels of microorganisms, fungi, Gram-negative bacteria and dust changed with quality of waste, activity in the plant etc. Levels of airborne microorganisms, endotoxins and dust could be considerably decreased in resource recovery plants if only waste of good quality, e.g. presorted materials, is handled. For composting plants the highest levels of airborne microorganisms were found during aeration, especially by indoor composting where levels of 8.3 × 105CFU of mesophilic microorganisms were found.

ISSN:0017-3134    

DOI:10.1080/00173139109432008

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

While returning from the 13th Polish Scientific Expedition to Antarctica, one of the authors (M.O.) collected airborne biological samples along the transect from the South Shetland Islands to Gdynia on the Baltic Seacoast of Poland. The journey aboard the Polish ship ORP “Heweliusz”, lasted from 4 March until 13 April 1990. During this period, two samples a day, exposed 12 h each, were collected in Petri dishes. The authors made preliminary identifications of plant and animal fragments in the samples. The most important finding was the presence of propagules of lichens (fragments of thallus, isidia soredia) in all samples. The relatively small number of pollen grains in samples could be accounted for by the season of collection when few pollen grains are airborne.

ISSN:0017-3134    

DOI:10.1080/00173139109432009

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The first results of an aerobiological study, with the help of a Burkard spore trap in Hungary, are reported. A pollen calendar of 1989 is presented. Out of the total identified sporomorphs, the most relevant 16 types of pollen and 10 of fungal spores are reported. We have pointed out, that in BudapestAmbrosiaandArtemisiapollen and some fungal spores are particularly responsible for the long lasting allergies to pollen and spores in the autumn. The pollen frequencies and the symptom scores of patients of the Pediatrics (Semmelweis Medical School, Budapest) showed a good correlation. Weekly reports are published in a newspaper and in television.

ISSN:0017-3134    

DOI:10.1080/00173139109432010

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Registration of viable microfungi in the Copenhagen outdoor air has been done since 1978 as a routine procedure for a service of the allergic patients.

ISSN:0017-3134    

DOI:10.1080/00173139109432011

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Totally 341 outdoors air samples were taken by Casella Airborne Sampler at a height of 7 m in the Allergy Centre of Kuwait between 1986 and 1988.Bacilluswas detected in 85.3% of the samples.Micrococcus(71.3%),Staphylococcus albus(65.4%). Gram-positive rods (53.4%) were more prevalent than gram-negative rods (23.7%). Higher counts were seen in 1986 (500 CFU m−3) compared to 1987 (407 CFU m−3) and 1988 (369 CFU m−3). Relatively higher counts were seen in August and September and a smaller peak was found in February and March. The correlation between the various types was always positive and was frequently highly significant. High counts were seen with strong winds. Among the meteorological factors, wind speed was the only significant factor. High average of bacteria counts were found when winds were blowing from the land (574 CFU m−3) compared with the sea (346.5 CFU m−3). Higher average counts were observed in the days with sand storms (1769 CFU m−3), with rising sand (534.8 CFU m−3) and the other days with dust phenomena, compared with clear weather (317 CFU m−3).

ISSN:0017-3134    

DOI:10.1080/00173139109432012

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor