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1.
During 1991 and 1992, hourly measurements were taken of solid particulates (size, 22–25 μm).Olea and grass pollen and spores. The results were then compared with symptoms recorded in patients consulting the Allergy Unit during the period of highest pollen concentrations (April–June). The spore-trap slides were studied by spectrophotometry in order to analyse the total solid particulates content in the air as a possible synergic agent of the pollen. This allowed the volume of material present in the air to be determined and expressed as a percentage of total optical density (OD). Allergy symptom data were obtained from the study of subjective clinical records completed by patients, who were required to note down the severity of a selected series of symptoms every 4 h using a scale from 0–3. The results showed a clear link during the season between hourly peaks and pollen concentrations, and the different patterns of response associated with the dominant pollen types. An attempt has been made to determine whether a relationship exists between the increment of the optical density and the symptomatic response. The positive relationship encountered seems to indicate that a synergic agent takes an active part in the effects produced by pollen in the patients.  相似文献   

2.
Abstract

Empirical evidence has consistently documented the direct relationship between infant mortality and socioeconomic inequality in the United States and numerous other countries. While the majority of these studies reveal an inverse relationship between socioeconomic level and infant mortality, not even this finding is free from disagreement. Furthermore, the specific nature and magnitude of this relationship has varied over time.

This study will examine the relationship between socioeconomic status and infant mortality in metropolitan Ohio by using birth and infant death data centered on the 2000 Census. The analyses presented herein will describe and analyze the relationship between infant mortality and socioeconomic status in metropolitan Ohio in the year 2000. The key finding is that in spite of remarkable declines in infant mortality during the past several decades, most notably in neonatal mortality, there continues to be a pronounced inverse association between the infant death rate and the economic status of a population.  相似文献   

3.
The investigation of airborne fungal spore concentrations was carried out in Szczecin, Poland between 2004 and 2006. The objective of the studies was to determine a seasonal variation in concentrations of selected fungal spore types due to meteorological parameters. The presence of spores of ten taxa: Cladosporium, Ganoderma, Alternaria, Epicoccum, Didymella, Torula, Dreschlera‐type, Polythrincium, Stemphylium and Pithomyces was recorded in Szczecin using a volumetric method (Hirst type). Fungal spores were present in the air in large numbers in summer. The highest concentrations were noted in June, July and August. The peak period was recorded in August for most of the studied spore types: Ganoderma, Alternaria, Epicoccum, Dreschlera‐type, Polythrincium and Stemphylium. Cladosporium and Didymella spores reached their highest concentrations in July while concentrations of Torula were highest in May and Pithomyces in September. Multiple regression analysis was performed for three fungal seasons: 2004, 2005, and 2006. Spore concentrations were positively correlated with minimum temperature for seven spore types in 2004, for five spore types in 2005, and for eight spore types in 2006 (significance level of α = 0.05). Some spore types are also significantly correlation among their concentrations, pressure, relative humidity and rain. Minimum temperature appeared to be the most influential factor for most spore types.  相似文献   

4.
Allergies due to airborne pollen affect a considerable percentage of Europeans; thus, the provision of health-related information services concerning pollen-induced symptoms can improve the overall quality of life. In this paper, we demonstrate the development of personalized, health-related, quality-of-life information services by adopting a data-driven approach. The data we use consist of allergic symptoms reported by people as well as detailed pollen count information of the most allergenic taxa. We apply computational intelligence methods in order to analyze symptoms, identify possible interrelationships with several pollen taxa and develop models that associate pollen count levels with allergic symptoms on a personal level. The results for the case of Austria show that this approach can lead to accurate personalized symptom forecasting models; we report an average correlation coefficient of r = 0.70 for a sample of 102 users of the Patients Hayfever Diary. We conclude that some of these models could serve as the basis for personalized health information services.  相似文献   

5.
Even though intra-guild predators frequently prey on the same species, it is unclear whether diet overlap between two predators is a source of interspecific competition or whether predators simply use the same abundant prey resource. We measured the extent to which the diets of barn owls (Tyto alba) and long-eared owls (Asio otus) in Israel overlap and examined whether yearly differences in diet overlap correlate with barn owl breeding success. Pianka’s index of niche overlap was positively related to barn owl population size but not to its breeding success. The number of breeding barn owls was higher when long-eared owls consumed more rodents, suggesting that diet overlap most likely increased when rodents became more abundant. Therefore, in Israel, when these two owl species prey more often on rodents, their diets are more similar and interspecific competition is reduced. Unlike sympatric populations in Europe, in years when rodents are less abundant in Israel long-eared owls switch to hunting alternative prey (e.g., birds), perhaps to avoid competition with barn owls.  相似文献   

6.
Class III histone deacetylases (HDACs) belong to the proteasome family, comprising seven family members identified in mammalian cells, identified Sirt1–Sirt7. As an important member of HDACs, Sirt3 is hotly debated for its multiple functions. It was reported that Sirt3 got involved in the alleviation of multiple diseases, including myocardial infarction, neuron ischemia, hypertrophy, and diabetic myopathy. Through regulating many cellular mechanisms, such as apoptosis, autophagy, and clearance of reactive oxygen species (ROS), Sirt3 played an important role in the alleviation of myocardial ischemia–reperfusion injury. Nowadays Sirt3-induced autophagy was indicated to be involved in the process of the development of myocardial ischemia–reperfusion injury. Sirt3 could both activate and inhibit autophagy process by activating different downstream signal pathways, such as Sirt3–AMP-activated protein kinase pathway, Sirt3–Foxo3a pathway, and Sirt3–superoxide dismutase–mitochondrial ROS pathway. Whereas the Sirt3-induced autophagy in different phases of myocardial ischemia–reperfusion has not been systematically illustrated. In this review, we summarized the regulated mechanisms found in these years and listed the updated research about the relationship between Sirt3 and autophagy which are both positive and negative during myocardial ischemia–reperfusion phase. We anticipated that we may controlled the activation of autophagy by regulating the concentration of Sirt3 in myocyte. By maintaining a proper expression of autophagy in different phases of myocardial ischemia–reperfusion, we could reduce the morbidity of patients with myocardial infarction apparently in the future.  相似文献   

7.
Apart from differences in circadian phase position, individuals with different morningness–eveningness levels vary in many more characteristics. Particularly consistent relationships have been observed between morningness–eveningness and mood. Eveningness has been associated with disadvantageous mood, e.g. depressiveness in healthy individuals, and mood disorders. A concept of social jetlag suggests that evening subjects function in less advantageous environments due to discrepancies between internal and social time (societies promote morning-oriented functioning), which results in their lowered mood. Individual temperament, as defined by the Regulative Theory of Temperament (RTT), refers to the capacity of the human organism to meet environmental requirements – the greater the capacity, the less negative impact of external conditions. Thus, the aim of this study is to determine which RTT traits are linked to both morningness–eveningness and mood dimensions and to test whether they account for the relationship between morningness–eveningness and mood. A sample of 386 university students (267 female) aged between 19 and 47 (M?=?21.15, SD?=?4.23) years completed the University of Wales Institute of Science and Technology (UWIST) Mood Adjective Check List, Morningness–Eveningness Questionnaire and Formal Characteristics of Behaviour – Temperament Inventory. Analyses revealed lower endurance (EN) and higher emotional reactivity (ER) related to eveningness as well as to lower hedonic tone (HT), energetic arousal (EA) and to higher tense arousal (TA). Moreover, eveningness was associated with lower HT, EA and higher TA. Among RTT traits, EN was most strongly related to eveningness, and mediation analyses revealed that this temperamental trait fully mediated the relationship between eveningness and the three mood dimensions. The remaining RTT traits did not provide more explanation of the association between morningness–eveningness and mood than EN itself. If subjects did not differ in EN, the association between morningness–eveningness and mood was absent. EN is discussed as a protective factor against negative consequences of social jetlag and particularly lowered mood in evening individuals.  相似文献   

8.
In this exploratory study, indoor and outdoor airborne fungal spores, pollen, and (1→3)-β-D-glucan levels were determined through long-term sampling (24-h) using a Button Personal Inhalable Aerosol Sampler. The air samples were collected in five Cincinnati area homes that had no visible mold growth. The total count of fungal spores and pollen in the collected samples was conducted under the microscope and Limulus Amebocyte Lysate (LAL) chromogenic assay method was utilized for the determination of the (1→3)-β-D-glucan concentration. For the combined number concentration of fungal spores and pollen, the indoor and outdoor geometric mean values were 573 and 6,435 m−3, respectively, with a geometric mean of the Indoor/Outdoor (I/O) ratio of .09. The geometric means of indoor and outdoor (1→3)-β-D-glucan concentrations were .92 and 6.44 ng m−3, respectively, with a geometric mean of the I/O ratio equal to .14. The I/O ratio of (1→3)-β-D-glucan concentration was found to be marginally greater than that calculated based on the combined number concentration of fungal spores and pollen. This suggests that (1→3)-β-D-glucan data are affected not only by intact spores and pollen grains but also by the airborne fragments of fungi, pollen, and plant material, which are ignored by traditional enumeration methodologies. Since the (1→3)-β-D-glucan level may elucidate the total exposure to fungal spores, pollen, and fungal fragments, its I/O ratio may be used as a risk marker for mold and pollen exposure in indoor environments.  相似文献   

9.
The porphyrinogenic drug 2-allyl-2-isopropylacetamide causes the degradation of microsomal cytochrome P-450 and inhibits the synthesis of catalase in rat liver. The inhibition of catalase synthesis follows the induction of delta-aminolaevulinate synthetase and the consequent overproduction of haem. The allylisopropylacetamide-mediated breakdown of cytochrome P-450 is a rapid event and has a reciprocal relationship to the pattern of delta-aminolaevulinate synthetase induction. Breakdown of cytochrome P-450 appears to be one of the conditions leading to the ;derepression' of delta-aminolaevulinate synthetase.  相似文献   

10.
The aim of the study was to investigate theAmbrosia pollen concentrations inselected Polish cities and for Kraków torelate it to some meteorological factors.Sampling was carried out in Kraków in1982–1997 and in Rabka in 1992–1996 with theuse of the gravimetric method. In Zakopane,Kraków, Ostrowiec witokrzyski,Warszawa and Pozna in 1995–1996 both thegravimetric and volumetric methods (Burkardtrap) were employed. In Kraków themonitoring has been performed since 1994 usingthe volumetric method. The results show theragweed pollen presence in August and Septemberwith the tendency to appear more frequently inAugust in some years. In Kraków (1994–1999)Ambrosia pollen was found either in thelast two weeks of August or in the first twoweeks of September which seems to be a regularand repeatable pattern every two years.Seasonal fluctuations of Ambrosia pollenconcentration do not show a clear increasingtendency except at Warszawa and Ostrowiecwitokrzyski in 1996 and at Krakówin 1999. Percentage of Ambrosia pollen inannual sums of total pollen is very low anddoes not exceed 1% except at Ostrowiecwitokrzyski in 1996 (1.2%) and atKraków in 1999 (2%). For Kraków theanalysis of some meteorological factors (Tmax,Tmin, precipitation, wind direction) wasperformed. High temperature and lack of rain orlow precipitation correlate well with ragweedpollen concentrations. During the Ambrosia pollen seasons ESE, E, S, SE, WSW, SWwind directions prevailed which could suggest along-distance transport from Ukraine, the CzechRepublic, Slovakia and also from Hungary, one ofthe most ragweed-polluted countries.  相似文献   

11.
Airborne pollen concentration was analysed for six plant taxa for the years 1980–2001 and related to temperature records for the same interval in two different areas in Austria. Both in valley areas (Innsbruck) and at higher altitudes (Obergurgl) the flowering period starts earlier, and lasts longer, and the peak values and pollen production were found to increase. Thus the potential for allergic responses to pollen has considerably increased.  相似文献   

12.
13.
Airborne fungal spore concentrations in Szczecin, Poland, were studied between 2004 and 2006 with the objective of determining a seasonal variation in the concentrations of selected fungal spore types in relation to meteorological parameters. The presence of spores of five taxa, namely, Cladosporium, Ganoderma, Alternaria, Leptosphaeria and Didymella, was recorded using a volumetric method (Hirst type). Fungal spores were present in the air in large numbers during the summer, with the highest concentrations recorded mainly in June, July and August. The peak concentrations of two of the studied spore types, Ganoderma and Alternaria, occurred in August, while the concentrations of Cladosporium, Leptosphaeria and Didymella spores were the highest in July. Multiple regression analysis was performed for three fungal seasons—2004, 2005 and 2006. Spore concentration was found to be positively correlated with the minimum temperature. For some spore types, there was also a significant correlation between concentrations, relative humidity and rain.  相似文献   

14.
Osteoclasts are unique cells that destroy the mineralized matrix of the skeleton. There is a “love–hate” relationship between the osteoclasts and the bone matrix, whereby the osteoclast is stimulated by the contact with the matrix but, at the same time, it disrupts the matrix, which, in turn, counteracts this disruption by some of its components. The balance between these concerted events brings about bone resorption to be controlled and to contribute to bone tissue integrity and skeletal health. The matrix components released by osteoclasts are also involved in the local regulation of other bone cells and in the systemic control of organismal homeostasis. Disruption of this regulatory loop causes bone diseases, which may end up with either reduced or increased bone mass, often associated with poor bone quality. Expanding the knowledge on osteoclast-to-matrix interaction could help to counteract these diseases and improve the human bone health. In this article, we will present evidence of the physical, molecular and regulatory relationships between the osteoclasts and the mineralized matrix, discussing the underlying mechanisms as well as their pathologic alterations and potential targeting.  相似文献   

15.
Summary By means of two Burkard Volumetric Spore-Traps situated in the center of Torino and Perugia, pollen was sampled between March and August for three years (1982–83–84). The two pollen spectra, with special reference to trees, were compared for pollen levels and duration of season in the two cities. Comments on vegetation in and around Torino and Perugia and meteorological data are compared with the two pollen spectra.   相似文献   

16.
BackgroundEmotion dysregulation has been consistently linked to psychopathology, and the relationship between disability and depressive symptomatology in old age is well-known.ObjectiveTo examine the mediational role of emotional dysregulation in the relationship between perceived disability and depressive symptomatology in older adults.MethodsTwo hundred eighty-three participants, aged 60–96 years (M ± SD = 74.22 ± 8.69; 62.9% women; 29.0% with long-term care support [LTC-S] and 71.0% community residents without LTC-S), were assessed with the Geriatric Depression Scale-8 (GDS-8), the World Health Organization Disability Assessment Schedule-2 (WHODAS-2), and the Difficulties in Emotion Regulation Scale-16 (DERS-16).ResultsA mediation model was established, which revealed: (1) a moderate association between WHODAS-2 and GDS-8 (β = 0.20; p < .001); (2) DERS-16 partially and weakly mediated the relationship between WHODAS-2 and GDS-8 (β = 0.003; p < .01). The model explained 31.9% of the variance of depressive symptoms. An inconsistent mediation model was obtained in the LTC-S group.ConclusionsGlobally, our findings indicate that disability has an indirect relationship with depressive symptomatology through emotional dysregulation (except for those in the LTC-S). Accordingly, we present suggestions for the treatment of depressive symptoms and for the inclusion of other emotion regulation variables in the study of the disability-depressive symptom link in future studies with older people in the LTC-S.  相似文献   

17.
The temporal changes in progesterone (Δ4P), 20α-dihydroprogesterone (20α-DHP) and luteinizing hormone (LH) concentrations in pseudopregnant (PSP) rats after treatment with a single subcutaneous Silastic-PUP tube containing 600 μg PGF were correlated. Progesterone levels fell and LH levels rose significantly 2h after initiation of treatment, while 20α-DHP levels were fond to increase significantly 12h after treatment. Since the changes in Δ P and LH concentrations occurred concurrently, it seems that the increase in LH levels could have been due to a direct effect of PGF2a on the ovary causing a reduction in Δ4P and thus a negative feedback effect on LH release. Alternatively, PGF2a might exert a direct effect on LH secretion at the hypothalamic-pituitary level.  相似文献   

18.
Daily deaths in ten large cities in the United States were correlated with weather elements for the months of January, April, July, and October of the years 1962–1965. In addition to showing the effects of spells of hot, humid weather and pollution episodes (extreme weather), it was determined that large interdiurnal changes of temperature, dewpoint, and pressure were accompanied by fluctuations in daily mortality. This applies to the northcentral and northeastern United States, where increases in mortality were coincident with prefrontal weather, decreases with postfrontal weather. Total mortality was the cause of death which correlated highest with the weather elements. Deaths over age 70, and under 70, follow in that order. There was little essential difference between arteriosclerotic heart disease and stroke in responsiveness to weather events.
Zusammenfassung Die täglichen Todesfälle in 10 Grosstädten der Vereinigten Staaten wurden mit Wetterelementen der Monate Januar, April, Juli und Oktober der Jahre 1962–1965 korreliert. Es konnte eine Beziehung zwischen Episoden von feuchtwarmemWetter und Luftverschmutzung und Mortalität nachgewiesen werden. Ausserdem ergab sich, dass grosse interdiurnale Schwankungen der Temperatur, des Taupunktes und Luftdruckes von Schwankungen der täglichen Mortalität begleitet sind. In den nordzentralen und nordöstlichen USA fielen Zunahme der Mortalität zusammen mit Vorfronten- und Abnahme mit Nachfronten-Wetter. Die Gesamtmortalität war die Todesursache, die am besten mit den Wetterelementen korrelierte, gefolgt von der Mortalität von Personen über und unter 70 Jahren. Ein wesentlicher Unterschied der Wetteranfälligkeit bei arteriosklerotischen Herzkrankheiten und Schlaganfall bestand nicht.

Resume On a mis en parallèle le nombre journalier de décès survenus dans 10 grandes villes des Etats-Unis et des paramètres météorologiques. L'étude se rapporte aux mois de janvier, avril, juillet et octobre des années 1962 à 1965. On a pu en tirer une corrélation entre les périodes chaudes à atmosphère polluée et une mortalité élevée. En outre, des variations interdiurnes prononcées de la température, du point de rosée et de la pression atmosphérique sont accompagnées de fluctuations marquées de la mortalité. Dans le nord-est, le nord et le centre des Etats-Unis, la mortalité augmente par situations préfrontales et diminue par situations postfrontales. La meilleure relation avec les éléments météorologiques est donnée par le nombre total de décès. Suivent ensuite les décès des gens âgés de plus de 70 ans, puis de ceux qui sont plus jeunes. On n'a par contre pas décelé d'effets météorotropiques marqués ni dans le cas de faiblesses cardiaques artériosclérotiques ni dans le cas d'attaques d'apopléxie.


Condensation of the author's Ph.D. dissertation in meteorology, at the University of Wisconsin, Madison, Wisconsin 1970.  相似文献   

19.
The limited availability of resources is predicted to impose trade‐offs between growth, reproduction and self‐maintenance in animals. However, although some studies have shown that early reproduction suppresses growth, reproduction positively correlates with size in others. We use detailed records from a large population of semi‐captive elephants in Myanmar to assess the relationships between size (height and weight), reproduction and survival in female Asian elephants, a species characterized by slow, costly life history. Although female height gain during the growth period overlapped little with reproductive onset in the population, there was large variation in age at first reproduction and only 81% of final weight had been reached by peak age of reproduction at the population level (19 years). Those females beginning reproduction early tended to be taller and lighter later in life, although these trends were not significant. We found that taller females were more likely to have reproduced by a given age, but such effects diminished with age, suggesting there may be a size threshold to reproduction which is especially important in young females. Because size was not linked with female survival during reproductive ages, the diminishing effect of height on reproduction with age is unlikely to be due to biased survival of larger females. We conclude that although reproduction may not always impose significant costs on growth, height may be a limiting factor to reproduction in young female Asian elephants, which could have important implications considering their birth rates are low and peak reproduction is young – 19 years in this population.  相似文献   

20.
Recent studies have shown that some species of Mimosa (Leguminosae-Mimosoideae) create resource islands (RI), rich in soil organic matter and nutrients, as well as in arbuscular mycorrhyzal fungal (AMF) spores, in the semi-arid Valley of Tehuacán-Cuicatlán. The relevance of this fact is that arid and semi-arid regions are characterized by low fertility soils and scarce precipitation, limiting plant species growth and development; this explains why the presence of AM fungi may be advantageous for mycorrhizal desert plants. Fluctuations in AMF spore numbers could be related to environmental, seasonal and soil factors which affect AMF sporulation, in addition to the life history of the host plant. The aim of this study was to asses the impact of spatial (resource islands vs open areas, OA) and seasonal (wet season vs start of dry season vs dry season) soil heterogeneity in the distribution and abundance of AMF spores in four different study sites within the Valley. We registered AMF spores in the 120 soil samples examined. Significant differences in the number of AMF spores were reported in the soil below the canopy of Mimosa species (RI) comparing with OA (RI > OA), and between Mimosa RI themselves when comparing along a soil gradient within the RI (soil near the trunk > soil below the middle of the canopy > soil in the margin of the canopy > OA); however, there were no significant differences between the soil closest to the trunk vs middle, and margin 's OA. Finally, more spores were reported in the soil collected during the wet season than during the dry season (wet > start of dry > dry). Therefore, the distribution of AMF spores is affected by spatial and seasonal soil heterogeneity. This study points out the relevance of Mimosa RI as AMF spore reservoirs and the potential importance of AM fungi for plant species survivorship and establishment in semi-arid regions. AM fungi have recently been recognized as an important factor determining plant species diversity in arid and temperate ecosystems.  相似文献   

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