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1.
Inquiries into homicides committed by psychiatric patients are currently mandatory under Department of Health guidance. They are often broadly defined in their terms of reference and almost always address not only the cause of the incident but also professional skill, practice, and culpability. Concurrent pursuit of both purposes is unlikely to maximise "learning from experience." Also, since inquiries can set their own thresholds for culpability, doctors can potentially be judged to a higher standard than would be required by the General Medical Council or negligence law. Lack of strict legal process increases the inherent potential unfairness to doctors. Investigation of cause and culpability should be separated and inquiries restricted to the former. There should also be a standing secretariat for inquiries to set terms of reference and to collate and distribute findings of inquiries. Widespread mandatory systematic audit of professional practice and service efficiency concerning risk assessment and management should largely replace costly ad hoc mandatory inquiries after homicides.  相似文献   

2.
As many as 700,000-1,000,000 Japanese are spending a substantial part of their life in bed not being able to resume standing position due to disease and/or accident. Our objectives were urgently derived from that fact. The research project group at Faculty of Medicine, University of Tokyo, in Japan have studied effects of prolonged horizontal bed rest on humans since 1990. Financial supports from the Japanese Ministry of Education (Grant-in aide for scientific research), National Aero Space Development Agency of Japan and Japan Federation for Health Sciences have enabled us to perform five prolonged bed rest experiments for 5 years from 1990 to 1994. Many scientists in Europe, America and Russia have already made a heap of studies on this subject since the latter half of 1940s (eg. 39). However, our studies mainly focused upon the effects of inactivity on human health to determine how to bring a human from inactivity back to an unrestricted active life. This short review is going to summarize our results obtained from 1990 to 1993.  相似文献   

3.
Conventional wisdom teaches that Thomas Huxley discredited Richard Owen in their debate over ape and human brains. This paper reexamines the dispute and uses it as a test case for evaluating the metaphysical realist, internal realist, and social constructivist theories of scientific knowledge. Since Owen worked in the Kantian tradition, his anatomical research illustrates the implications of internal realism for scientific practice. As an avowed Cartesian, Huxley offered a well developed attack on Owen's position from a metaphysical realist perspective. Adrian Desmond's political retrospective on the dispute affords the additional opportunity to contrast internal realism with social constructivism. I argue that since Huxley ultimately based his attack on his valuing Europeans as superior to blacks, his argument illustrates the hazards of accepting the metaphysical realist promise of value free science. Desmond overlooks this racial dimension of the dispute, and his work shows how social constructivism can distract the historian and philosopher from even the social meaning of science. As internal realists like Putnam have argued, values enter science not from without, but from within the very process of science itself.  相似文献   

4.
Innovation is often assumed to be the work of a talented few, whose products are passed on to the masses. Here, we argue that innovations are instead an emergent property of our species'' cultural learning abilities, applied within our societies and social networks. Our societies and social networks act as collective brains. We outline how many human brains, which evolved primarily for the acquisition of culture, together beget a collective brain. Within these collective brains, the three main sources of innovation are serendipity, recombination and incremental improvement. We argue that rates of innovation are heavily influenced by (i) sociality, (ii) transmission fidelity, and (iii) cultural variance. We discuss some of the forces that affect these factors. These factors can also shape each other. For example, we provide preliminary evidence that transmission efficiency is affected by sociality—languages with more speakers are more efficient. We argue that collective brains can make each of their constituent cultural brains more innovative. This perspective sheds light on traits, such as IQ, that have been implicated in innovation. A collective brain perspective can help us understand otherwise puzzling findings in the IQ literature, including group differences, heritability differences and the dramatic increase in IQ test scores over time.  相似文献   

5.
One of the first envatted brains, the most cyborgian element of J. D. Bernal’s 1929 futuristic manifesto, The world, the flesh and the the devil, proposed a technological solution to the dreary certainty of mortality. In Bernal’s scenario the brain is maintained in an ‘out of body’ but ‘like-body’ environment—in a bath of cerebral–spinal fluid held at constant body temperature. In reality, acquiring prospective immortality requires access to very different technologies—those that allow human organs and tissues to be preserved in a quite ‘inhuman’ life-world—the cryogenic storage chamber. Like Bernal, today’s cryonicists consider that immortality can be secured through preservation of the brain alone. In this article I trace attempts to preserve or suspend life, and especially brain function, through the application of new ‘technologies of immortality’. Drawing together historical information on the development of refrigeration, cryopreservation, transplantation, and nanotechnologies, I explore the uneasy relationship between cryonics and the technology on which it depends for its success—cryogenics. In so doing, I argue that the ability to successfully realize the science fiction fantasy of human immortality will rest on a moral and scientific parasitism: the capacity to use the biotechnological artifacts or proxies—cryogenically preserved brains, archived brains, tissues, and immortalized cell lines—derived from the dead, in order to prolong life.  相似文献   

6.
Fully differentiated neurons in adult mammalian brains do not divide; consequently, their metaphase chromosomes have never been examined. Here we report metaphase chromosome constitutions of cortical neurons in adult mice visualized by a nuclear transfer technique. We found that although some reconstructed oocytes cloned from neuronal nuclei have an apparently normal karyotype, the majority do not. Regardless of chromosome morphology, nuclei of adult neurons totally lack the ability to support embryonic development. These findings support the hypothesis that fully differentiated neurons in adult mammalian brains are genomically altered.  相似文献   

7.
Morphometric and hormonal measures were collected from 21 captive savanna baboons (Papio cynocephalus) maintained at the Tulane National Primate Research Center in order to determine age-related patterns in leptin levels over the life course as well as their relationships to body composition and adrenal and gonadal steroids. Comparison of leptin levels between peri-pubertal, adolescent, young adult, and fully mature males show lower levels among adolescent as compared with young adult males (P = 0.05 by Kruskal-Wallis ANOVA). In addition, abdominal fat varied among age groups (P = 0.003 by Kruskal-Wallis ANOVA) with the peri-pubertal animals lower than the adolescents, young adults, and prime adults. However leptin was not related to any measure of body composition, including abdominal fat, or to adrenal hormones (dehydroepiandrosterone, dehydroepiandrosterone-sulfate, and cortisol) or gonadal hormones (testosterone and estradiol). Age-related changes in leptin appear similar to those reported for captive rhesus macaques, while the failure to find an association between leptin and abdominal fat is interestingly different. These results confirm elevated levels of leptin in captive baboons compared with their wild counterparts and suggest that they result from changes in fetal development.  相似文献   

8.
Professional experience and lay wisdom teach us the benefits of exercise and the hazards of idleness. Yet the myth persists that "bed rest is good for you" when ill or convalescing. Abundant scientific evidence in the past 50 years has demonstrated the specific damage done to each of the body''s organ systems by inactivity. Both aging and inactivity lead to strikingly similar kinds of deterioration. I summarize the data from military and veterans'' hospitals, rehabilitation experience, aerospace research, and gerontology and review the physiologic and metabolic changes of aging and inactivity, along with strategies to help prevent the iatrogenic complications of bed rest.  相似文献   

9.
10.
Recordings of ongoing neural activity with EEG and MEG exhibit oscillations of specific frequencies over a non-oscillatory background. The oscillations appear in the power spectrum as a collection of frequency bands that are evenly spaced on a logarithmic scale, thereby preventing mutual entrainment and cross-talk. Over the last few years, experimental, computational and theoretical studies have made substantial progress on our understanding of the biophysical mechanisms underlying the generation of network oscillations and their interactions, with emphasis on the role of neuronal synchronization. In this paper we ask a very different question. Rather than investigating how brain rhythms emerge, or whether they are necessary for neural function, we focus on what they tell us about functional brain connectivity. We hypothesized that if we were able to construct abstract networks, or "virtual brains", whose dynamics were similar to EEG/MEG recordings, those networks would share structural features among themselves, and also with real brains. Applying mathematical techniques for inverse problems, we have reverse-engineered network architectures that generate characteristic dynamics of actual brains, including spindles and sharp waves, which appear in the power spectrum as frequency bands superimposed on a non-oscillatory background dominated by low frequencies. We show that all reconstructed networks display similar topological features (e.g. structural motifs) and dynamics. We have also reverse-engineered putative diseased brains (epileptic and schizophrenic), in which the oscillatory activity is altered in different ways, as reported in clinical studies. These reconstructed networks show consistent alterations of functional connectivity and dynamics. In particular, we show that the complexity of the network, quantified as proposed by Tononi, Sporns and Edelman, is a good indicator of brain fitness, since virtual brains modeling diseased states display lower complexity than virtual brains modeling normal neural function. We finally discuss the implications of our results for the neurobiology of health and disease.  相似文献   

11.
During the period of brain development, the levels of nonhydroxy- and hydroxy-cerebrosides in the cytosol from brains of jimpy mutants were determined by high-performance liquid chromatography and compared to those in the rest of the particulates from the same brains as well as those in the littermate controls. The concentrations of cerebrosides in jimpy brain preparations were much lower than in controls at all ages. In another experiment, [U-14C]glucose was injected intraperitoneally into jimpy mutants and their littermate controls. The amounts of radioactivity incorporated into cerebrosides and sulfatides in brain cytosol, the microsome-rich fraction, and the rest of the heavier particles were determined. Although the total radioactivity incorporated into these lipids was much lower in jimpy, the specific activities were 2–3 times the control value in all subcellular fractions.  相似文献   

12.
The 2001 honoring of Russian twin researcher, Dr. Inna V. Ravich-Shcherbo, at the Tenth International Congress on Twin Studies (ISTS), in London, brought timely recognition to an international colleague. It also marked an occasion for reflecting on the course of twin studies in Russia. Historical trends and current accomplishments are examined with an eye toward future developments. Next, the distinguished careers of Russian monozygotic twins, Drs. Alexander and Andrew Fingelkurts, exemplify twin research findings on intelligence and occupational choice, and illuminate the status of twin studies and other scientific research in their country, are told. Their life histories are followed by the initially tragic, but ultimately heartwarming, story of young twins, Max and Andy, whose physical disabilities were overcome through the efforts of an empathic war veteran. The recent Moscow Summer School, the first in a three-time lecture series, encouraged crucial academic exchange among scientific investigators and students from around the world. Final thoughts are that much can be learned and much can be accomplished, given that we continue to nurture the twin-related resources available to us.  相似文献   

13.
In an endeavor to screen bioactive compounds present in vegetables with effective mechanism using in silico method lead us to develop a vegetable phytochemicals and their target database (VPTD). The VPTD is a unique bioinformatics resource that compiles information about phytochemicals from vegetables and their mechanism. VPTD contains 2496 phytochemicals from 27 vegetables, their 3D images and their 1337 possible biological mechanism. Each phytochemical contain records of seven data fields providing detailed information on name, source, amount present, structure and mechanistic information. This information has been manually extracted and manually verified from numerous sources, including other electronic databases, textbooks and scientific journals. VPTD is fully searchable and supports extensive text search. The main focus of the VPTD is on providing possible mechanism of phytochemicals, which will help in discovery of potential drugs from one of the common bioresource-vegetable. VPTD is freely available. AVAILABILITY: The database is available for free at http://www/vptd.in.  相似文献   

14.
There have been suggestions that heat caused by cerebral metabolic activity may constrain mammalian brain evolution, architecture, and function. This article investigates physical limits on brain wiring and corresponding changes in brain temperature that are imposed by thermodynamics of heat balance determined mainly by Na+/K+-ATPase, cerebral blood flow, and heat conduction. It is found that even moderate firing rates cause significant intracellular Na+ build-up, and the ATP consumption rate associated with pumping out these ions grows nonlinearly with frequency. Surprisingly, the power dissipated by the Na+/K+ pump depends biphasically on frequency, which can lead to the biphasic dependence of brain temperature on frequency as well. Both the total power of sodium pumps and brain temperature diverge for very small fiber diameters, indicating that too thin fibers are not beneficial for thermal balance. For very small brains blood flow is not a sufficient cooling mechanism deep in the brain. The theoretical lower bound on fiber diameter above which brain temperature is in the operational regime is strongly frequency dependent but finite due to synaptic depression. For normal neurophysiological conditions this bound is at least an order of magnitude smaller than average values of empirical fiber diameters, suggesting that neuroanatomy of the mammalian brains operates in the thermodynamically safe regime. Analytical formulas presented can be used to estimate average firing rates in mammals, and relate their changes to changes in brain temperature, which can have important practical applications. In general, activity in larger brains is found to be slower than in smaller brains.  相似文献   

15.
Parents have a critical role in adolescent health. The association of adolescents'' perceptions of family relationships with adolescent health was investigated using a sample of 67 female adolescents who participated in eight focus group discussions, utilising a purposeful sampling method. All tape-recorded data were fully transcribed and content analysis was performed. Three themes were identified, namely emotional support, responsible parents and well-informed parents. With regard to some of the challenges in Iranian adolescents'' relationships with their parents, it is necessary to educate parents to be alert to their role in adolescent health.  相似文献   

16.
Large brain sizes in humans have important metabolic consequences as humans expend a relatively larger proportion of their resting energy budget on brain metabolism than other primates or non-primate mammals. The high costs of large human brains are supported, in part, by diets that are relatively rich in energy and other nutrients. Among living primates, the relative proportion of metabolic energy allocated to the brain is positively correlated with dietary quality. Humans fall at the positive end of this relationship, having both a very high quality diet and a large brain size. Greater encephalization also appears to have consequences for aspects of body composition. Comparative primate data indicate that humans are 'under-muscled', having relatively lower levels of skeletal muscle than other primate species of similar size. Conversely, levels of body fatness are relatively high in humans, particularly in infancy. These greater levels of body fatness and reduced levels of muscle mass allow human infants to accommodate the growth of their large brains in two important ways: (1) by having a ready supply of stored energy to 'feed the brain', when intake is limited and (2) by reducing the total energy costs of the rest of the body. Paleontological evidence indicates that the rapid brain evolution observed with the emergence of Homo erectus at approximately 1.8 million years ago was likely associated with important changes in diet and body composition.  相似文献   

17.
One function of sleep is thought to be the restoration of energy stores in the brain depleted during wakefulness. One such energy store found in mammalian brains is glycogen. Many of the genes involved in glycogen regulation in mammals have also been found in Drosophila melanogaster and rest behavior in Drosophila has recently been shown to have the characteristics of sleep. We therefore examined, in the fly, variation in the glycogen contents of the brain, the whole head and the body throughout the rest/activity cycle and after rest deprivation. Glycogen in the brain varies significantly throughout the day (p=0.001) and is highest during rest and lowest while flies are active. Glycogen levels in the whole head and body do not show diurnal variation. Brain glycogen drops significantly when flies are rest deprived for 3 h (p=0.034) but no significant differences are observed after 6 h of rest deprivation. In contrast, glycogen is significantly depleted in the body after both 3 and 6 h of rest deprivation (p<0.0001 and p<0.0001, respectively). Glycogen in the fly brain changes in relationship to rest and activity and demonstrates a biphasic response to rest deprivation similar to that observed in mammalian astrocytes in culture.  相似文献   

18.
Adolescents’ behavior is often a matter of concern, given their increased likelihood of enacting antisocial behaviors, which cause disruptions in the social order and are potentially harmful for the adolescents themselves and for the people around them. In this six-wave longitudinal study we sought to examine the interplay among maternal empathy, multiple indicators of mother-adolescent relationship quality (i.e., balanced relatedness, conflict, and support), and adolescent antisocial behaviors rated both by adolescents and their mothers. Participants for the current study were 497 Dutch adolescents (56.9% males) followed from age 13 to 18, and their mothers. A series of cross-lagged panel models revealed reciprocal associations between maternal empathy and mother-adolescent relationship quality and between mother-adolescent relationship quality and adolescent antisocial behaviors. Interestingly, we also found some indirect effects of adolescent antisocial behaviors on maternal empathy mediated by mother-adolescent relationship quality. Overall, this study further highlights a process of reciprocal influences within mother-adolescent dyads.  相似文献   

19.
In France, over 45 millions people watch TV every day for more than 3 hours. Science and image get well together since most TV watchers trust this media and rely on it (more than on any other source) for their scientific information. This emphasizes the power of images, which do not always deliver information, but can be naively regarded as creating communication. Image is necessary and an event which does not generate images is a non-event. Images are more than just a support for scientific messages: technologies have produced an enormous amount of images which allow us to uncover the mysteries of the world and Universe, their beauty and delicacy. We can be fascinated by the discovery of the invisible world which surrounds us, and science has truly generated artistic masterpieces even though we should remember that its primary goal is to understand the world rather than to create images.  相似文献   

20.
Meinertzhagen, I.A. 2010. The organisation of invertebrate brains: cells, synapses and circuits. —Acta Zoologica (Stockholm) 91 : 64–71 Invertebrate brains are structurally diverse. Neuron numbers range from ~102 to 108 in different groups, compared with larger numbers in vertebrate brains, ~107 to 1014. The underpopulated brains of invertebrates are noted in their extreme cases for having few cells, and neurons that can be identified from animal to animal, many known in great detail. Although few in number, invertebrate neurons nevertheless comprise many classes. Correlated with the paucity of their number they are sparsely connected, many having ~50 synapses or fewer. Synaptic densities, roughly 1 per μm3 of neuropile, differ little from those for much larger vertebrate neurons. Invertebrate neurons differ from their vertebrate counterparts in the position of their soma, generally in a cortex surrounding the neuropile that consequently occupies a relatively small volume. Their axons typically lack myelin and, supporting a range of conduction velocities, have diameters that differ over a wide range, from 103 to 10?1μm. Nerves with thousands of axons differ from neuropile fascicles, which typically have 20 or less. Unlike most vertebrate synapses, but like those of the vertebrate retina, synapses in many invertebrate groups – probably all ecdysozoans and possibly some lophotrochozoans – have synaptic contacts with multiple postsynaptic elements, dyads, triads and so on.  相似文献   

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