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1.
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   

2.
The study examines the relationship between sudden changes in weather conditions in summer, represented by (1) sudden air temperature changes, (2) sudden atmospheric pressure changes, and (3) passages of strong atmospheric fronts; and variations in daily mortality in the population of the Czech Republic. The events are selected from data covering 1986–2005 and compared with the database of daily excess all-cause mortality for the whole population and persons aged 70 years and above. Relative deviations of mortality, i.e., ratios of the excess mortality to the expected number of deaths, were averaged over the selected events for days D−2 (2 days before a change) up to D+7 (7 days after), and their statistical significance was tested by means of the Monte Carlo method. We find that the periods around weather changes are associated with pronounced patterns in mortality: a significant increase in mortality is found after large temperature increases and on days of large pressure drops; a decrease in mortality (partly due to a harvesting effect) occurs after large temperature drops, pressure increases, and passages of strong cold fronts. The relationship to variations in excess mortality is better expressed for sudden air temperature/pressure changes than for passages of atmospheric fronts. The mortality effects are usually more pronounced in the age group 70 years and above. The impacts associated with large negative changes of pressure are statistically independent of the effects of temperature; the corresponding dummy variable is found to be a significant predictor in the ARIMA model for relative deviations of mortality. This suggests that sudden weather changes should be tested also in time series models for predicting excess mortality as they may enhance their performance.  相似文献   

3.
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   

4.
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   

5.
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   

6.
Abstract

Galton believed that his data on hereditary genius support purely genetic inheritance. On the contrary, analysis under a simple model shows no clear resolution of genetic and cultural inheritance in this material, or generally, unless adoptive relations, monozygous twins, and/or environmental indices are included in a design adequate to test the assumptions under which they are informative.  相似文献   

7.
Essential oils can be produced in this country, but extensive investigations and careful planning are of prime importance.  相似文献   

8.
9.
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   

10.
11.
Summary When millet was grown in short-term pot experiments in the greenhouse, in the red-clay and sand-veld soils of Southern Rhodesia and the red clay loams of Uganda, a very close correlation was obtained between labile soil phosphorus and the aluminium- and iron-bound phosphate in these soils. A large increase in labile soil phosphorus was obtained when millet was grown in Uganda soils that had been stored in the air-dry condition for 15 weeks, and a greater increase after 24 weeks. The increase is attributed to the mineralisation of soil organic phosphorus. The maximum temperature used to dry the soils had no effect on the labile soil phosphorus values obtained.  相似文献   

12.
The investigation of airborne pollen and fungalspore concentrations was carried out in Cracowbetween 1997–1999. For this study thevolumetric method has been employed (Burkard).At the same time the clinical diagnosis ofpollen allergy in 40 patients was obtained onthe basis of an interview, positive skin pricktests with pollen extracts and increasedspecific IgE level. An increase in seasonalallergy symptoms in all patients occurred fromthe middle of May to the middle of August.Eighty eight percent of the patients (35 out of40) were sensitive to Poaceae pollen and about50% of them were additionally sensitive totree and herb pollen excluding grasses. Forpatients with additional allergy to tree pollenthe seasonal symptoms started at the end ofMarch (Betula) while for patients withadditional allergy to herb pollen it wasextended to the middle of September (Artemisia).Five people out of 40 revealed positive skinreactions to Alternaria spores and anincrease in specific IgE level. Positive skinreaction to Cladosporium spores with noincrease in specific IgE level occurred in 2patients. The increase in seasonal allergysymptoms in people sensitive to Alternariaspores noted in July and August could becaused not only by these spores but also byPoaceae pollen.  相似文献   

13.
Evidence for the identity of β-galactosidase and β-fucosidase enzymes in the house mouse was obtained by examination of the enzyme activities in animals from different crosses between C57BL/Kl mice with high galactosidase and fucosidase activities and DBA/2/Kl mice with low activities. There is a strong correlation between the activities of these two enzymes in different tissues of F2 animals. A comparison of the fractionation properties of β-galactosidase and β-fucosidase showed that the two activities had a parallel distribution and identical thermostability. These data suggest that the same enzyme catalyzes the hydrolysis of both substrates.  相似文献   

14.
15.
In the “Eastern Pontides” (NE Turkey), the intense volcanic activity accompanying carbonate-siliceous sedimentation during the Late Cretaceous period ensured the occurrence of thick volcano-sedimentary sequences. Seventy-one radiolarian species belonging to 26 genera were identified from five stratigraphic sections of the Upper Cretaceous sequences between Trabzon and Giresun areas in NE Turkey. These species were obtained from the lower Turonian–lower Coniacian strata of the Çe?meler Formation, the Coniacian–lower Santonian strata of the Elmal? Dere Formation and the upper Santonian strata of the Ça?layan Formation. Coniacian–Campanian fauna, consisting of planktonic foraminifera Hedbergella, Marginotruncana, Globotruncana, Whiteinella and biserial heterohelicids as well as radiolarians, was recovered from the red pelagic limestones of the Elmal? Dere Formation known as marker horizon.  相似文献   

16.
The mechanical arrangement of the PD organ of Cancer has been studied and equations derived which relate its length to the articulation angle of the PD joint and to the angle which the receptor strand makes with the dactylopodite flexor tendon. These relationships are discussed in the light of the anatomy of the PD articulation.  相似文献   

17.
Iteroparous species examined from the northwest Atlantic demonstrated distinct relationships between feeding and reproduction. Two species showed an increase in feeding during the developing, ripe and running stages of reproduction, indicative of the ramper pattern. Four species showed an increase in feeding after spawning in the spent or resting stage of reproduction, indicative of the rester pattern. Two species exhibited no distinct pattern. Evidence from other species confirms these major patterns. This information may be useful to determine the effectiveness of different management measures, particularly in relation to feeding or spawning aggregations. There are two major feeding-reproductive patterns for fishes along a continuum of possibilities.  相似文献   

18.
19.
Abstract

From information on mortality of Jews obtained from individual death certificates and population data from surveys of the Jewish population undertaken in 1963 and 1987, age‐specific death rates and life expectancy of the Jewish population of Rhode Island are compared with those of the total white population for 1963 and 1987 to assess changing differentials. The Jewish mortality experience continues to differ from that of the larger population even while both groups have experienced noticeable improvements. For males, the age standardized rates have widened in favor of Jews as have the life expectancies at birth and the percentage surviving to old age. By contrast, for females, the standardized death rate has widened considerably in favor of whites, while life expectancy has improved almost identically for both groups and therefore remained about equal, as it was in 1963. Reasons for these patterns are explored through attention to differences between Jews and the general white population in death rates at particular stages of the life cycle. Jews tend to be more advantaged at all but the most advanced ages, age groups in which proportionally more of the Jewish population and Jewish deaths are concentrated.  相似文献   

20.
Although the ecological effects of surface wateracidification are now well researched, factorscontrolling the abundance and occurrence of aquaticorganisms in unpolluted acid-sensitive systems arepoorly known. The Høylandet region in central Norwayexperiences relatively low levels of atmosphericpollution and its surface waters, although acid, arenot significantly acidified. Hence lakes and streamsin this region were selected to study the influence ofwater chemistry on diatom algae. Relationships betweenthe two were explored using the multivariate techniqueof canonical correspondence analysis (CCA). Theprincipal water chemistry variables influencingspecies composition of periphytic diatoms were foundto be pH and water colour. Furthermore, therelationship between species abundance and pH wassufficiently strong to enable reconstruction of wateracidity from diatom data. Establishing the nature ofaquatic communities in atmospherically clean butgeologically sensitive regions is an important meansof identifying control systems against which therecovery of acidified lakes in polluted regions can beassessed. The Høylandet region has the potential toprovide a Europe-wide control system of this naturebut much further work is required to follow up andextend the results of this preliminary study.  相似文献   

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