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1.
While climate change is inherently a global problem, its public health impacts will be experienced most acutely at the local and regional level, with some jurisdictions likely to be more burdened than others. The public health infrastructure in the U.S. is organized largely as an interlocking set of public agencies at the federal, state and local level, with lead responsibility for each city or county often residing at the local level. To understand how directors of local public health departments view and are responding to climate change as a public health issue, we conducted a telephone survey with 133 randomly selected local health department directors, representing a 61% response rate. A majority of respondents perceived climate change to be a problem in their jurisdiction, a problem they viewed as likely to become more common or severe over the next 20 years. Only a small minority of respondents, however, had yet made climate change adaptation or prevention a top priority for their health department. This discrepancy between problem recognition and programmatic responses may be due, in part, to several factors: most respondents felt personnel in their health department--and other key stakeholders in their community--had a lack of knowledge about climate change; relatively few respondents felt their own health department, their state health department, or the Centers for Disease Control and Prevention had the necessary expertise to help them create an effective mitigation or adaptation plan for their jurisdiction; and most respondents felt that their health department needed additional funding, staff and staff training to respond effectively to climate change. These data make clear that climate change adaptation and prevention are not currently major activities at most health departments, and that most, if not all, local health departments will require assistance in making this transition. We conclude by making the case that, through their words and actions, local health departments and their staff can and should play a role in alerting members of their community about the prospect of public health impacts from climate change in their jurisdiction. 相似文献
2.
Dena M. Smith Jonathan D. Marcot 《Proceedings. Biological sciences / The Royal Society》2015,282(1805)
Coleoptera (beetles) is the most species-rich metazoan order, with approximately 380 000 species. To understand how they came to be such a diverse group, we compile a database of global fossil beetle occurrences to study their macroevolutionary history. Our database includes 5553 beetle occurrences from 221 fossil localities. Amber and lacustrine deposits preserve most of the beetle diversity and abundance. All four extant suborders are found in the fossil record, with 69% of all beetle families and 63% of extant beetle families preserved. Considerable focus has been placed on beetle diversification overall, however, for much of their evolutionary history it is the clade Polyphaga that is most responsible for their taxonomic richness. Polyphaga had an increase in diversification rate in the Early Cretaceous, but instead of being due to the radiation of the angiosperms, this was probably due to the first occurrences of beetle-bearing amber deposits in the record. Perhaps, most significant is that polyphagan beetles had a family-level extinction rate of zero for most of their evolutionary history, including across the Cretaceous–Palaeogene boundary. Therefore, focusing on the factors that have inhibited beetle extinction, as opposed to solely studying mechanisms that may promote speciation, should be examined as important determinants of their great diversity today. 相似文献
3.
PHYLOGENETIC RELATIONSHIPS AMONG PAPER WASP SOCIAL PARASITES AND THEIR HOSTS (HYMENOPTERA: VESPIDAE; POLISTINAE) 总被引:1,自引:0,他引:1
James M. Carpenter Joan E. Strassmann Stefano Turillazzi Colin R. Hughes Carlos R. Solís Rita Cervo 《Cladistics : the international journal of the Willi Hennig Society》1993,9(2):129-146
Abstract— Cladistic analyses of data from allozyme polymorphisms in paper wasp social parasites and their hosts do not support the hypothesis that social parasites are most closely related to their hosts. Electrophoretic data are adduced for nine species of Polistes , including all three known species of social parasites ( Sulcopolistes ) and their hosts. Three different coding methods are investigated; in no case do the social parasites cluster most closely with their hosts. Rather, there is limited evidence that they form a monophyletic group. However, formal taxonomic recognition of Sulcopolistes is not justified, as it renders Polistes sensu stricto paraphyletic. Although the social parasites are not most closely related to their hosts, hosts and parasites belong in the same subgenus and share many characteristics that may have facilitated the exploitation and deception practised by the parasites on the hosts. 相似文献
4.
The nomadic Romani (gypsy) people are known for their deep-rooted traditions, but most of their history is recorded from external sources. We find evidence for a Romani genetic lineage in England long before their recorded arrival there. The most likely explanations are that either the historical record is wrong, or that early liaisons between Norse and Romani people during their coincident presence in ninth to tenth century Byzantium led to the spread of the haplotype to England. 相似文献
5.
N. E. Langmore 《Ethology : formerly Zeitschrift fur Tierpsychologie》1999,105(2):125-136
The songs of a population of wild dunnocks, Prunella modularis , were recorded over 3 yrs to investigate song tutor choice by first year males. Young males often settled on occupied territories as subordinates and most of their earliest territorial interactions were with the male on whose territory they settled (the co-male). Yearlings learned their song repertoire from their comales and territorial neighbours. This supports results of laboratory studies which suggest that social interactions influence song tutor choice and that yearlings are most likely to learn from the males that are most aggressive towards them. Repertoire overlap between neighbouring males was high (76%), so learning the repertoire of the comale may provide yearling males with a 'short cut' route to learning a few of the songs of every neighbour. 相似文献
6.
M. B. King 《BMJ (Clinical research ed.)》1988,297(6642):182-184
An unselected series of outpatients infected with the human immunodeficiency virus (HIV) who attended two London hospitals were interviewed to assess their relationship with their general practitioner. Although most of the 192 patients were registered with a general practitioner, the doctors of only one half knew of the diagnosis. Patients feared a negative reaction from their general practitioner or were concerned about confidentiality. Although those who had told their doctor had received favourable reactions, few general practitioners attempted to counsel or educate their patients. The patients who previously had been open about their homosexuality were not more likely to have told their general practitioner of their HIV infection. Although most did not think that general practitioners were well informed about AIDS, half of the patients wished that general practitioners could take a bigger part in their care. 相似文献
7.
R F Shaw 《The Journal of heredity》1991,82(1):77-80
Codons that differ from a terminator triplet by only a single base are sometimes thought, because of their greater risk of undergoing a harmful mutation, to be kept at a reduced frequency by natural selection. The present study on human genes shows that these codons are infrequent, but their low frequency is not directly related to their risk of mutation to terminator. Rather, it is a consequence of their ending in A or G; comparable A-ending and G-ending codons that are not mutable to terminator are also infrequent. Natural selection does not appear to have depressed the frequency of mutable-to-terminator codons by directly eliminating some of them individually. It may have depressed their frequency indirectly by adjusting mutation rates in the population so that most of the purine-ending codons--and consequently most of the mutable-to-terminator ones as well--are infrequent. 相似文献
8.
The aims of the study were to analyse the sport activity and eating habits of obese people in their childhood and adulthood. The research was underpinned by a survey questionnaire containing 37 variables which was completed by 71 people attending the obesity programme. The frequencies and contingency tables were calculated, whereas statistical significance was established at a 5% significance level. The analysis of the results showed that more than one-half of the survey respondents joined the obesity programme primarily for reasons of health and well-being. Most obese people did not engage in any organised sport activity in their childhood, nor did most of their parents. The respondents practiced sport in their childhood to a greater extent if their parents were also physically active and if they guided and encouraged their children. No less than one-third of the respondents were overweight in their childhood, of whom two-thirds did not participate in any organised sport activity. The majority of the respondents (85.9%) are currently engaged in an organised sport activity in their adulthood, mainly due to their participation in the weight reduction programme; most of them practice sport twice a week. Their eating habits are encouraging; the share of skipped meals is considerably lower and practically negligible compared to that in childhood. It has to be emphasized that most of them are of opinion that obese people have difficulties finding expert information on obesity, nutrition and sport activities as well as weight management centers and institutions. 相似文献
9.
Rudy Boonstra 《Oecologia》1984,62(1):126-131
Summary Field evidence indicates that adult microtines, especially females, may be a major cause of poor juvenile survival and this may be instrumental in their population regulation. This suggests that males and females behave differently towards young animals. To examine how adult males, nonlactating females, and lactating females behave towards strange young, I introduced young animals into the home cage of the adults. Lactating females were most aggressive towards young; most males investigated them; most nonlactating females ignored them. However, discriminant function analysis indicated a great deal of overlap in the behavior of the classes. None of the classes behaved differently towards young of either sex. Females did not vary their behavior during lactation. Behavior varied among lactating females, with 55% showing little aggression and 20% showing a great deal. Most lactating females showed similar behavior in each of their bouts: docile females remained docile, aggressive females remained aggressive. I conclude that lactating females are most aggressive towards strange young. These results are consistent with the field evidence, which suggests that adult females depress juvenile survival and recruitment and that the main culprits are breeding females. 相似文献
10.
11.
Great tits were played recordings of one of their own songs, and a song of the same type from a neighbour and one from a stranger (from more than 500 m away). The birds matched their own songs most often and those of strangers least. We had predicted that strangers would be matched most, because previous work had shown an association between matching and a strong response. An analysis using a difference index showed that the birds matched most often when the stimulus song was very similar in detailed structure to their own rendition of the song. This was confirmed in a second experiment in which we played ‘similar’ and ‘different’ renditions recorded from strangers. However, once the effect of similarity was partialled out there was a residual tendency to match strangers more than neighbours, as we had first predicted. We discuss the implications of these results for perception of song categories by the birds, possible use by the birds of their own songs as ‘standards’ and the functional significance of matching. 相似文献
12.
Effect of Host Cell Wall Material on the Adsorbability of Cofactor-requiring T4 总被引:2,自引:2,他引:0
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The adsorbability of T4 on host cells was determined as a function of time after their liberation from infected cells. Freshly liberated (nascent) particles are readily adsorbed but lose their adsorbability with a half-time of about 2 days at 5 C, but only about 20 min at 37 C. They can be made adsorbable again with an alpha-amino acid cofactor like l-tryptophan, and this state of adsorbability can be stabilized by cell wall material from Escherichia coli. Such stabilized particles lose their adsorbability at a rate similar to that at which nascent particles lose theirs. Most freshly liberated particles are observed by means of electron microscopy to have "debris" attached to their baseplates and to have most of their six, long tail fibers free, whereas "old" particles that have lost their adsorbability appear relatively "clean" with most of their tail fibers wrapped around their sheaths. Nascent particles have densities that are lower than those of old particles. The material responsible for nascent adsorbability seems to be a fragment of the host's cell wall, for nascent adsorbability is destroyed by lysozyme. Furthermore, nascent T4 particles liberated from host cells with radioactively labeled walls carry the label in density gradients but lose it as they lose adsorbability. In addition, only a small proportion of particles liberated from infected spheroplasts are nascently adsorbable, whereas most particles liberated from intact cells are adsorbable. 相似文献
13.
Ornithine decarboxylase (ODC) catalyzes the first and rate limiting step in the biosynthesis of polyamines in most eukaryotes.
Because polyamines have pleiotropic and often dramatic effects on cellular processes at both high and low concentrations,
ODC expression is tightly controlled. ODC is regulated by a family of polyamine-induced proteins, antizymes, which bind to,
and inactivate it. In mammals, and apparently most vertebrates, antizymes are in turn antagonized by proteins called antizyme
inhibitors. Antizyme inhibitors are homologs of ODC that have lost their decarboxylation activity but have retained their
ability to bind antizyme, in most cases even more tightly than ODC. We present a phylogenetic analysis of over 200 eukaryotic
homologs of ODC and evaluate their potential to be either true ODCs or catalytically inactive proteins that might be analogs
of the previously identified antizyme inhibitors. This analysis yielded several orthologous groups of putative novel antizyme
inhibitors each apparently arising independently. In the process we also identify previously unrecognized ODC paralogs in
several evolutionary branches, including a previously unrecognized ODC paralog in mammals, and we evaluate their biochemical
potential based on their pattern of amino acid conservation. 相似文献
14.
Animals breeding only once late in life should spend most of the time during their one reproductive season attempting to reproduce. Contrary to this prediction, we found that the individuals of three species of sticklebacks (Pisces: Gasterosteidae) spent very short periods of time on their breeding ground. Tidal flooding of the site controlled patterns of fish immigration and emigration. Inundations early in the breeding season brought in new immigrants which replaced most resident fish. However, towards the end of the breeding season there was less immigration and a higher percentage of the residents remained in their pools. We expected to see movements among pools by surplus males searching for sites to establish a territory; instead, few fish moved among pools, and most of those that did were females. A high energetic cost of breeding in this unstable habitat may best explain these residency patterns. 相似文献
15.
Call-timing mechanisms among anuran males calling within choruses are frequent, and previous studies have indicated that midwife toad females respond preferentially to these mechanisms. The results of multi-speaker tests performed here with midwife toads suggest that the temporal order of male calls within a dense chorus can determine the ability of females to locate the most attractive calls (in this instance the low-frequency calls emitted by larger males). When call emission was regular in the multi-speaker tests, most females chose the most attractive option (i.e., the speaker emitting the lower-frequency call). When call emission was not regular, however, most females failed to reach the most attractive option, selecting the speaker that emitted immediately after that emitting the most attractive call. These results support the idea that there may be benefits for smaller males that emit their less attractive calls close to those of larger, more attractive males in dense choruses. Less attractive males could exploit the attractiveness of nearby larger males calls by alternating their calls in an unordered sequence to reach receptive females. 相似文献
16.
A Weil 《Cellular and molecular biology, including cyto-enzymology》2001,47(8):1343-1351
Whatever their own policies may be, developing countries will inevitably be affected by the development of genetically-modified organisms in industrialized countries. While maintaining a cautious attitude, most of these countries wish to keep their options open, thus protecting themselves from the risk of being deprived of future technologies that might allow them to achieve self-sufficiency in food production, to resolve certain problems confronting their most vulnerable populations and to preserve the international competitiveness of their products. Companies should see that it is in their interest to help these countries implement their own policies, notably through an open attitude to industrial property. If the value of genetic engineering is thus confirmed, then it perhaps in this manner that GMOs will earn the legitimacy required to make them acceptable to the people of Northern countries where the majority of solvent markets are located. 相似文献
17.
Bacteria can clearly enhance their survival by expanding their genetic repertoire. However, the tight packing of the bacterial genome and the fact that the most evolved species do not necessarily have the biggest genomes suggest there are other evolutionary factors limiting their genome expansion. To clarify these restrictions on size, we studied those protein families contributing most significantly to bacterial-genome complexity. We found that all bacteria apply the same basic and ancestral 'molecular technology' to optimize their reproductive efficiency. The same microeconomics principles that define the optimum size in a factory can also explain the existence of a statistical optimum in bacterial genome size. This optimum is reached when the bacterial genome obtains the maximum metabolic complexity (revenue) for minimal regulatory genes (logistic cost). 相似文献
18.
The growth of most mensural characters of Krobia guianensis and Crenicichla saxatilis during early development was explained by a split regression indicating inflection in allometry at specific standard lengths. Double-centred PCA revealed morphological transformations during ontogeny mostly under the influence of the maximum body depth and the maximum caudal peduncle width, the area of the caudal fin and the horizontal diameter of the eye contributing also, but to a lesser extent. Young K. guianensis switched to larger prey at the end of the period when the growth of most of their studied mensural characters demonstrated an inflection, but young C. saxatilis changed their diet at a much smaller size than that at which an inflection occurred. However, in the lower reservoir sites, most young juveniles of K. guianensis and C. saxatilis did not switch to larger items during their ontogeny and micro-crustaceans occurred more frequently in their diet. It is hypothesized that the low net energy gained when eating such small prey may explain why the young of both species were thinner at these sites than in their undisturbed habitats. If food resources of young cichlids do not improve in the Petit-Saut reservoir, it is hypothesized that these species will develop stunted populations there. 相似文献
19.
Edwin B. Powers 《The Journal of general physiology》1922,4(3):305-317
1. The ability of marine fishes to absorb oxygen at low tension from the sea water is more or less dependent upon the hydrogen ion concentration of the water. 2. The ability of fishes to withstand wide variations in the range of hydrogen ion concentration of the sea water can be correlated with their habitats. The fishes that are most resistant to a wide variation in the hydrogen ion concentration are most cosmopolitan in their habitat. Those that are least resistant to a variation in the hydrogen ion concentration are the most restricted in their range of habitat. 3. There is a close correlation between the optimum condition of the sea water for the absorption of oxygen at low tension by the herring (Clupea pallasii), the condition of the sea water to which they react positive and that in which they are found most abundantly. 4. It is suggested that the variation in the ability to absorb oxygen at low tension at a given pH of individuals of a species is dependent upon the alkaline reserve of the blood of the individual fish. 相似文献
20.
Propagule size and parental care: the "safe harbor" hypothesis 总被引:3,自引:0,他引:3
R Shine 《Journal of theoretical biology》1978,75(4):417-424
Species that protect their offspring (by egg-brooding or live-bearing) produce larger (and hence fewer) propagules than do related species that do not protect their offspring. This result holds true in most animal groups showing parental care. Analysis of these data supports the hypothesis that propagule size evolves in response to relative survivorship rates during and after the propagule stage: natural selection is most likely to favor large egg size when the egg is a safe harbor. 相似文献