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1.
Vaccines have been among the most effective tools for addressing global public health challenges. With the advent of genomics, novel approaches for vaccine discovery are opening up new opportunities for vaccine development and applications, particularly with the expectation of personalized vaccines and the possibility of addressing a broader range of infectious diseases. In this context, it is useful to reflect on the social contexts of vaccine development as these have been influenced by social, ethical, political challenges. This article discusses the historical context of vaccine controversies and factors that help explain public acceptance and resistance, illustrating that these challenges go well beyond simple public misunderstandings. The broader vaccine challenges evident along the innovation trajectory, from development to commercialization and implementation include problems in research and development, organizational issues, and legal and regulatory challenges that may collectively contribute to public resistance or confidence. The recent history of genomics provides further lessons that the developing field of vaccinomics can learn from.  相似文献   

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Evolution has no foresight, but produces ad hoc solutions by tinkering with available variation. A new study demonstrates how evolution nevertheless prepares organisms for the future by increasing their evolvability.  相似文献   

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A hypothesis is advanced according to which the level of environmental comfort is estimated by embryo brain during the embryogeny. Depending on the level of comfort the organism prepares itself to the postembryonic life predicting its most probable conditions on the basis of the current conditions of the embryogeny. It is postulated that the embrionic conditions determine the peculiarities of reactions to stress, sex behavior, and rate of development.  相似文献   

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This paper addresses the transformation of forest bureaucracy, which has occurred in accordance with a national policy shift from “fence-and-fine” to “participatory” conservation, and its impact on resource users at Gunung Halimun-Salak National Park in Indonesia and analyzes causal relationships between this transformation and its outcome. The research suggests that the mode of conservation governance was transformed through the implementation of new ways of communication and interaction, learning processes and perceptional and behavioral changes. The result of this analysis indicates that while the dominant discourse of participatory conservation assumes a primary importance of satisfying local economic needs for conservation, what should be emphasized is the process of trust-building and learning between frontline staff and local resource users without which the durability of a conservation institution is questionable. The analysis also reveals both challenges and limitations of a trust-building approach: while the approach effectively functions to halt forest degradation, it might not lead to the rehabilitation of forest ecosystem.  相似文献   

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The human gastric pathogen, Helicobacter pylori, colonizes more than 50% of the world population and is a well-known cause of peptic ulcer disease. H. pylori has been epidemiologically linked to various other diseases, among which its putative link with certain complex diseases such as type 1 diabetes mellitus (T1DM) is of interest. Although antibiotic resistance is a significant clinical problem in H. pylori infection control, the exact cause and much of the underlying mechanisms of T1DM are not clearly understood. In addition, commensal microflora, gut-adapted microbial communities, and plausible roles of some of the chronic human pathogens add an important dimension to the control of T1DM. Given this, the present review attempts to analyze and examine the confounding association of H. pylori and T1DM and the approaches to tackle them, and how the emerging field of vaccinomics might help in this pursuit.  相似文献   

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Perception of the smell of a food precedes its ingestion and perception of its flavor. The neurobiological underpinnings of this association are not well understood. Of central interest is whether the same neural circuits code for anticipatory and consummatory phases. Here, we show that the amygdala and mediodorsal thalamus respond preferentially to food odors that predict immediate arrival of their associated drink (FO+) compared to food odors that predict delivery of a tasteless solution (FO-) and compared to the receipt of the drink. In contrast, the left insula/operculum responds preferentially to the drink, whereas the right insula/operculum and left orbitofrontal cortex respond to FO+ and drink. These findings indicate separable and overlapping representation of anticipatory and consummatory chemosensation. Moreover, since ratings of perceived pleasantness of FO+, FO-, and drink were similar, the response in the amygdala and thalamus cannot reflect acquired affective value but rather predictive meaning or biological relevance.  相似文献   

7.
Feeding innovations and parasitism in birds   总被引:2,自引:0,他引:2  
The rate of behavioural innovation, such as opportunistic feeding innovation, may facilitate adaptation to novel environments. Because parasites may affect how their hosts adopt novel means of resource acquisition, or because opportunistic behaviours may involve the risk of being exposed to a large parasite fauna, we hypothesize an evolutionary link between the rate of feeding innovations and parasitism. We investigated the phylogenetic relationship between relative frequency of feeding innovations (adjusted for research effort and population size) and relative size of immune defense organs (as a relative measure of parasite-mediated selection) and the prevalence of blood parasites in birds. Using generalized least squares models, we found that species with relatively large bursa of Fabricius, thymus, and spleen had higher rates of feeding innovations than species with small immune defense organs. Similarly, there was a positive interspecific association between feeding innovation and haematozoa prevalence. These relationships were not confounded by migration, relative brain size, geographical distribution, and male plumage brightness. Analyses of causality relying on evolutionary modelling of discrete variables and path analysis suggest that increasing rate of feeding innovation may place species under intense selection due to parasitism. Therefore, behavioural adaptation by feeding innovation seems to have consequences for the coevolutionary arm race between parasites and hosts.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 441–455.  相似文献   

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Deflective displays direct predatory attacks to body parts thatare relatively invulnerable or can be lost without disastrousconsequences. Usually, these behaviors are directed to predatorspoised to attack at very close quarters. In contrast to suchreactive deflection is anticipatory deflection in situationsthat entail a high risk of being ambushed. Because a predatorcan draw nearer during display, reactive deflection is feasibleonly when the predator is already close. A graphical model showslines relating probability of death to distance from the predatorwhen the prey displays and when it flees without display. Reactivedeflection decreases the probability of death when the predatoris closer than the intersection of these lines, but increasesthe probability of death beyond the intersection. If the predatoris detected when far enough away, the best option is to fleewithout displaying. Anticipatory deflection may increase theprobability of surviving ambush immediately after arriving ata new location but increase the risk of attracting the attentionof other predators. This risk increases with time since stoppingas more predators arrive that did not detect the prey movingto its new location. Anticipatory deflection can be selectivelyfavored only during a brief interval immediately after the preyarrives. The interval increases with benefit of display to survivalif ambushed. It decreases with increases in probabilities ofbeing detected and killed due to display. Examples of thesedisplays and other taxa in which they may be sought are discussed.  相似文献   

11.
Reliable estimates of time are essential for initiating interceptive actions at the right moment. However, our sense of time is surprisingly fallible. For instance, time perception can be distorted by prolonged exposure (adaptation) to movement. Here, we make use of this to determine if time perception and anticipatory actions rely on the same or on different temporal metrics. Consistent with previous reports, we find that the apparent duration of movement is mitigated by adaptation to more rapid motion, but is unchanged by adaptation to slower movement. By contrast, we find symmetrical effects of motion-adaptation on the timing of anticipatory interceptive actions, which are paralleled by changes in perceived speed for the adapted direction of motion. Our data thus reveal that anticipatory actions and perceived duration rely on different temporal metrics.  相似文献   

12.
The origin or evolutionary `success' of taxa is often attributed to key innovations-aspects of organismal phenotype that promote diversification. Different ways of delimiting taxa and measuring `success' (i.e. number or longevity of species, morphological variety or differential control of energy) give rise to different ideas of how key innovations might operate. Key innovations may enhance competitive ability, relax adaptive trade-offs or permit exploitation of a new productive resource base. Recent key innovation studies comparing species richness in extant sister clades may miss important observations possible only with consideration of the fossil record, traditional higher taxa and phenotypic diversity.  相似文献   

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The present research concerns anticipatory postural adjustments (APA), with the purpose of determining whether they are preprogrammed and of specifying their biomechanical finality. The experimental situation allowed us to distinguish between the voluntary movement itself (an upper limb elevation) and the postural adjustments associated with it. To this aim, the upper limb kinematics, evaluated from an accelerometer fixed at wrist level, were compared to the whole body dynamics, recorded by means of a force platform. Movements, executed in series of five, were studied according to three conditions: bilateral flexions (BF) and unilateral flexions (UF), with (IUF) and without (OUF) an additional inertia, of the stretched upper limb(s). Six right handed adults were tested twice. Results showed that the ground reaction resultant forces as well as the ground reaction resultant moment about the vertical axis presented reproducible variations before and after the onset of upper limb acceleration. The biomechanical organization of APA corresponded, for the three experimental conditions, to an upward and forward acceleration of the body center of gravity, and also, for UF, to a resultant moment directed towards the contralateral side. The duration of APA varied with the characteristics of the forthcoming voluntary movement, increasing significantly from BF to OUF and from OUF to IUF. It is concluded that APA correspond to dynamic phenomena which are centrally preprogrammed. The inertia forces associated with APA may, when the time comes, balance the inertia forces due to the movement of the mobile limb therefore counteracting the disturbance to postural equilibrium.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
Explanations for taxonomic diversity in a particular clade often implicate evolutionary innovations, possessed by members of the clade, that are thought to have favoured diversification. We review such “key innovation”; hypotheses, the ecological mechanisms involved, and potential tests of such hypotheses.

Key innovation hypotheses can be supported by evidence of ecological mechanism and by comparative tests. We argue that both are necessary for convincing support. In fact, few key innovation hypotheses are currently backed by either one.

We group ecological mechanisms of diversification in three major classes. Diversification may be spurred by innovations that: I) allow invasion of new adaptive zones; II) increase fitness, allowing one clade to replace another; or III) increase the propensity for reproductive or ecological specialization. Key innovations in different classes are likely to produce different evolutionary patterns, and therefore may be supported by different kinds of ecological evidence.  相似文献   

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Coral Reefs - Tubelip wrasses were probably the first modern fish group to feed on corals, an ability that has been linked to their unusual lips. However, the only detailed account of these lips is...  相似文献   

18.
The importance of the intensive control of blood glucose in patients with diabetes has been well documented in several large scale studies. Attempts to attain strict glucose control when managing diabetes have traditionally utilized daily subcutaneous injections of human insulin. This strategy has offered improvements in glycaemic control but is unable to replicate fully the normal diurnal plasma profile of endogenous human insulin. Advances in protein engineering techniques have, however, resulted in the formulation of a number of insulin analogues that offer more desirable properties of absorption from the subcutaneous depot and hence improved insulin profiles in patients with diabetes. Concurrent to the development of insulin analogues, devices to deliver insulin either subcutaneously or by other routes have also advanced. These novel delivery strategies are also likely to contribute to improved glycaemic control for patients with diabetes in the future.  相似文献   

19.
Mutational robustness facilitates evolutionary innovations. Gene duplications are unique kinds of mutations, in that they generally increase such robustness. The frequent association of gene duplications in regulatory networks with evolutionary innovation is thus a special case of a general mechanism linking innovation to robustness. The potential power of this mechanism to promote evolutionary innovations on large time scales is illustrated here with several examples. These include the role of gene duplications in the vertebrate radiation, flowering plant evolution and heart development, which encompass some of the most striking innovations in the evolution of life.  相似文献   

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