Aerobiological monitoring for fungal spores in a rehabilitation hospital in Northern Italy

In the setting of an aerobiological study of confined environments and environmental prevention of nosocomial infections, aerobiological monitoring of 22 areas in Montescano Medical Rehabilitation Centre (Pavia) was performed in three different months: February, May, and August, 1994. A Lanzoni 3000 spore trap was used for the monitoring. Examination of the results showed that, in the environments monitored, the indoor presence of fungi increased progressively over the three periods considered. The behaviour of individual genera of fungi differed. In the winter periodPenicillium andAspergillus were the most commonly encountered genera.Cladosporium was the dominant genus from the spring to the summer while the yeasts had their maximum counts in the spring morning. The use of air conditioning, combined with the low air exchange between outdoors and indoors in some of the environments certainly played a part in the low concentrations of these latter aerofungi.     

Odor preference in honeybees as a function of amount of reward: Tests of two explanations

How does a foraging honeybee come to prefer a color or odor paired with the large of two amounts of sucrose solution to a color or odor paired with the smaller amount? One hypothesis is that the attractiveness of a color or odor is based on the strength of its association with the taste of sucrose, which increases with the duration of concurrent color-taste or odor-taste stimulation. Another hypothesis is that the attractiveness of a color or odor is based on association with the afferent consequences of feeding, which are different for the two amounts. Both hypotheses were tested in experiments on proboscis-extension conditioning, a technique that provides better control of stimulation than is possible in work with free-flying foragers. In Experiments 1–3, which were designed to test the first hypothesis, an odor that accompanied the ingestion of sucrose on training trials was found to elicit extension of the proboscis when subsequently it was presented alone, but the duration of concurrent stimulation had no significant effect on the probability or persistence of the response. In Experiments 4 and 5, which were designed to test the second hypothesis, an odor that immediately followed the ingestion of sucrose on training trials failed to elicit extension of the proboscis when subsequently it was presented alone. The results support neither hypothesis.     

Mercury translocation in and evaporation from soil. I. soil lysimeter experiments with 203Hg‐radiolabeled compounds

Due to a considerable increase of anthropogenic mercury emissions, the mercury load of many soils has risen significantly, for instance in northern Europe. Understanding the fate of mercury in soils is a prerequisite for assessing the effects of ecotoxicological concern. This paper presents a method for obtaining qualitative and quantitative information about mercury translocation in and evaporation from soil. Soil lysimeters were treated with ²⁰³Hg‐labeled HgCl₂ and CH₃HgCl and irrigated with artificial rain. It was demonstrated that the leaching of Hg can be detected by measuring the relative y‐activity throughout the soil profile by means of Na(TI)I detectors. Furthermore, the set‐up was designed to allow detection of Hg volatilization from soil by using traps of iodized charcoal, followed by a potassium peroxodisulfate solution and measuring the γ‐activity. The amount of radioactive Hg in soil leachate was measured by a Na(Tl)I well‐type detector after upconcentration. The determination of monomethyl ²⁰³Hg was been performed by extraction procedures that isolate the methyl mercury compounds. The amount of ²⁰³Hg retained in the soil profile and the real depth of leaching were determined by stratifying the soil profile at the end of the experiment and measuring the y‐activity. With control of all pathways of Hg, the experimental design allows performance of a mass balance analysis.     

Postharvest disease control in mangoes using high humidity hot air and fungicide treatments

The disease control efficacy of quarantine heat treatments developed for fruit fly disinfestation in mangoes cv. Kensington Pride was evaluated in this study. Heat was applied using high humidity (>95% r.h.) hot air (HHHA) at temperatures ranging from 47–49°C. Anthracnose, caused by Colletotrichum gloeosporioides, was well controlled in mangoes heated to a core temperature of 46°C, 47°C or 48°C for 24, 10 or 8 min respectively, prior to ripening at 23°C for 16 days. Stem end rot, caused by Dothiorella dominicana and Lasiodiplodia theobromae, was not satisfactorily controlled by these treatments. In a subsequent experiment, fruit were immersed in a hot benomyl (0.5 g a.i. litre“¹ at 52°C for 5 min) or unheated prochloraz (0.25 ml a.i. litre¹ at 28°C for 30 s) dip before or after the application of HHHA (core temperature of 47°C for 10 min). During storage at 23°C for 15 days, the incidence of stem end rot was reduced by HHHA alone, although immersion in hot benomyl either before or after HHHA treatment greatly improved stem end rot control. HHHA treatment (core temperature of 46.5°C for 10 min) alone reduced the incidence of anthracnose in mangoes stored at 13°C for 14 days prior to ripening at 22°C, although a combination treatment consisting of HHHA and either hot benomyl or unheated prochloraz gave complete control of anthracnose under these storage conditions. HHHA treatment alone gave no control of stem end rot in mangoes stored at 13°C prior to ripening at 22°C. A supplementary hot benomyl treatment was required for acceptable control of this disease in cool-stored mangoes. The development of yellow skin colour in fruit was accelerated by HHHA treatment.     

Le Jas d’en Biel 2, nouveau site gravettien du piémont est-méditerranéen des Pyrénées

The Corbières massif forms the lowest part of the Eastern Pyrenees, and as such is the easiest natural passage to connect the coastal plains of Languedoc and Roussillon in Southern France with those of Gironès and Barcelona in Northern Spanish Catalonia. This geographical situation confers on each of the sites discovered in this passage a role of milestone that can allow us to apprehend the dynamics of anthropic movements and relationships across these spaces. In 2007, the presence of a first Gravettian site in this Northern Pyrenean foothill was published: Jas d’en Biel 1. This discovery filled an “archaeological void” between the Gravettian sites of Languedoc and those of Spanish Catalonia. The discovery of a new site: Jas d’en Biel 2, 300 m from the first, reinforces the Gravettian presence in this region. The fact that the two sites present similar characteristics in terms of anthropic choices (solar orientation, proximity to a watercourse, lightness of the soil, protection from the wind, etc.) are all parameters that demonstrate the choices made by Gravettian men. The respective compositions of the lithic industries of the series do not show significant differences, allowing us to imagine a certain synchronism between the two sites. Burins are the most numerous tools, but at Jas d’en Biel 2 we find specimens close to the Raysse type that were absent from Jas d’en Biel 1. Jas d’en Biel 2, as well as its neighbor Jas d’en Biel 1, shows similarities with certain sites in Languedoc, such as Bois-des-Brousses, La Treille, La Verrière, the caves of Bize or La Crouzade. These are usually small deposits that belong to terminal moments of the Gravettian period. All these parameters point to similarities between the Languedoc sites and Jas d’en Biel 1 and 2. The geographical position of the Corbières massif allows us to consider the Jas d’en Biel sites as the last milestones of the Gravettian period upstream from the crossing of the Pyrenean passes, before the sites of the Serinyà region, such as l’Arbreda. Recent surveys carried out in the same valley of the Ravin d’en Saman have made it possible to locate and identify several other open-air settlements related to the Gravettian lato sensu. An analysis of intra- and extra-site characteristics will aim to understand the parameters that led men to settle in this micro-zone, as well as the reasons for this “concentration”.     

Biotechniques for air pollution control

This paper gives an overview of present biological techniques for the treatment of off-gases and the techniques that are being developed at the moment. The characteristics, advantages, disadvantages, costs and application area are discussed and compared. Biological off-gas treatment is based on the absorption of volatile contaminants in an aqueous phase or biofilm followed by oxidation by the action of microorganisms. Biofilters, bioscrubbers and biotrickling filters are used for elimination of odour and bioconvertable volatile organic and inorganic compounds and are enjoying increasing popularity. This popularity is a result of the low investment and operational costs involved compared to physico-chemical techniques and the elimination efficiencies that can be obtained. The operational envelop is still extending to higher concentrations and gas flow rates (exceeding 200,000 m³ h^–1) and a broader spectrum of degradable compounds. Research and development on the use of membranes and the addition of activated carbon or a second liquid phase to the biological systems may lead to a more efficient elimination of hydrophobic compounds and buffering of fluctuating loads. Shorter adaptation periods can be obtained by inoculation with specialized microorganisms. Improved design and operation are made possible by the growing insights in the kinetics and microbiology and supported by the development of models describing biological off-gas treatment. In conclusion, biotechniques are efficient and cost effective in treating off-gases with concentrations of biodegradable contaminants up to 1–5 g/m³. They could play a justified and important role in air pollution control in the coming years.Abbreviations VOC volatile organic compound - NO _x gaseous oxides of nitrogen     

REVISING A CLASSIC BUTTERFLY MIMICRY SCENARIO: DEMONSTRATION OF MÜLLERIAN MIMICRY BETWEEN FLORIDA VICEROYS (LIMENITIS ARCHIPPUS FLORIDENSIS) AND QUEENS (DANAUS GILIPPUS BERENICE)

Batesian and Müllerian mimicry relationships differ greatly in terms of selective pressures affecting the participants; hence, accurately characterizing a mimetic interaction is a crucial prerequisite to understanding the selective milieux of model, mimic, and predator. Florida viceroy butterflies (Limenitis archippus floridensis) are conventionally characterized as palatable Batesian mimics of distasteful Florida queens (Danaus gilippus berenice). However, recent experiments indicate that both butterflies are moderately distasteful, suggesting they may be Müllerian comimics. To directly test whether the butterflies exemplify Müllerian mimicry, I performed two reciprocal experiments using red-winged blackbird predators. In Experiment 1, each of eight birds was exposed to a series of eight queens as “models,” then offered four choice trials involving a viceroy (the putative “mimic”) versus a novel alternative butterfly. If mimicry was effective, viceroys should be attacked less than alternatives. I also compared the birds' reactions to solo viceroy “mimics” offered before and after queen models, hypothesizing that attack rate on the viceroy would decrease after birds had been exposed to queen models. In Experiment 2, 12 birds were tested with viceroys as models and queens as putative mimics. The experiments revealed that (1) viceroys and queens offered as models were both moderately unpalatable (only 16% entirely eaten), (2) some birds apparently developed conditioned aversions to viceroy or queen models after only eight exposures, (3) in the subsequent choice trials, viceroy and queen “mimics” were attacked significantly less than alternatives, and (4) solo postmodel mimics were attacked significantly less than solo premodel mimics. Therefore, under these experimental conditions, sampled Florida viceroys and queens are comimics and exemplify Müllerian, not Batesian, mimicry. This compels a reassessment of selective forces affecting the butterflies and their predators, and sets the stage for a broader empirical investigation of the ecological and evolutionary dynamics of mimicry.     

Early needle senescence and thinning of the crown structure of Picea abies as induced by chronic SO2 pollution. II. Field data basis, model results and tolerance limits

Field data on the sulphur and cation budget of growing Norway spruce canopies (Picea abies [L.] Karst.) are summarized. They are used to test a spruce decline model capable of quantifying effects of chronic SO₂ pollution on spruce forests. At ambient SO₂ concentrations, acute SO₂ damage is rare, but exposure to polluted air produces reversible thinning of the canopy structure with a half-time of a few years. Canopy thinning in the spruce decline model is highest (i) at elevated SO₂ pollution, (ii) in the mountains, (iii) at unfertilized sites with poor K⁺, Mg²⁺ or Zn²⁺ supply, (iv) at low spruce litter decomposition rates, and (v) acidic, shallow soils at high annual precipitation rates in the field and vice versa. Model application using field data from Würzburg (moderate SO₂ pollution, alkaline soils, no spruce decline) and from the Erzgebirge (extreme SO₂ pollution, acidic soils in the mountains, massive spruce decline) predicts canopy thinning by 2–11% in Würzburg and by 45–70% in the Erzgebirge. The model also predicts different SO₂-tolerance limits for Norway spruce depending on the site elevation and on the nutritional status of the needles. If needle loss of more than 25% (damage class 2) is taken to indicate ‘real damage’ exceeding natural variances, then for optimum soil conditions SO₂ tolerance limits range from (27.3 ± 7.4) μg m^?3 to (62.6 ± 16.5) μg m^?3. For shallow and acidic soils, SO₂ tolerance limits range from (22.0 ± 5.5) μg m^?3 to (37.4 ± 7.5) μ m^?3. These tolerance limits, which are calculated on an ecophysiological data basis for Norway spruce are close to epidemiological SO₂-toIerance limits as recommended by the IUFRO, UN-ECE and WHO. The observed statistical regression slope of the plot (damaged spruce trees vs. SO₂-pollution) in west Germany is confirmed by modelling (6% error). Model application to other forest trees allows deduction of the observed sequence of SO₂-sensitivity: Abies > Picea > Pinus > Fagus > Quercus. Thus, acute phytotoxicity of SO₂ seems not to be involved in ‘forest decline’. Chronic SO₂-pollution induces massive canopy thinning of Abies alba and Picea abies only at unfavourable sites, where natural stress factors and secondary effects of SO₂pollution act together to produce tree decline.     

Simplified methods for monitoring petroleum‐contaminated ground water and soil vapor

Portable meters and simplified gas Chromatographic (GC) techniques were investigated for monitoring volatile hydrocarbon (HC), CO₂, and O₂, concentrations in groundwater, exhaust gases, and soil vapor during in situ remediation using soil vapor extraction (SVE) and air sparging (AS). Results of groundwater samples analyzed in‐house using a headspace technique compared well to split samples analyzed by a certified analytical laboratory (r² = 0.94). SVE exhaust gas HC and CO₂ concentrations measured using a GT201 portable HC/O₂ meter and a RA‐411A meter (GasTech), respectively, were highly correlated with in‐house laboratory GC analyses (r² = 0.91). O₂ concentrations fell in a small range and meter analyses were not well correlated with laboratory analyses. Results of soil gas monitoring were not as well correlated as those for exhaust gases for HC, CO₂, or O₂, perhaps due to environmental conditions such as changes in relative humidity or the wider range of soil gas values. Overall, the meters were good indicators of vapor contamination, they greatly simplified estimates of total HC mass removal, and they allowed estimates of the biological contribution to contaminant removal during the remediation process.     

苯甲醛对果蝇视觉联想记忆的阻断

采用飞行模拟系统,以视觉模式为线索、热惩罚为负强化因子,对于在不同发育时期经受苯甲醛处理过的果蝇的视觉飞行定向条件化进行了检验。苯甲醛气味分别作用于果蝇幼虫和成虫阶段,将阻断果蝇成虫建立视觉联想记忆的能力;雌性果蝇在处女期对苯甲醛气味的接触,会阻断其子代建立视觉联想记忆,这种视觉联想记忆的能力可以通过对其子代连续３代的正常饲养而逐渐得到恢复。