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Separate body- and world-referenced representations of visual space in parietal cortex.

In order to direct a movement towards a visual stimulus, visual spatial information must be combined with postural information. For example, directing gaze (eye plus head) towards a visible target requires the combination of retinal image location with eye and head position to determine the location of the target relative to the body. Similarly, world-referenced postural information is required to determine where something lies in the world. Posterior parietal neurons recorded in monkeys combine visual information with eye and head position. A population of such cells could make up a distributed representation of target location in an extraretinal frame of reference. However, previous studies have not distinguished between world-referenced and body-referenced signals. Here we report that modulations of visual signals (gain fields) in two adjacent cortical fields, LIP and 7a, are referenced to the body and to the world, respectively. This segregation of spatial information is consistent with a streaming of information, with one path carrying body-referenced information for the control of gaze, and the other carrying world-referenced information for navigation and other tasks that require an absolute frame of reference.

Animals↗

Collective dynamics of 'small-world' networks.

Networks of coupled dynamical systems have been used to model biological oscillators, Josephson junction arrays, excitable media, neural networks, spatial games, genetic control networks and many other self-organizing systems. Ordinarily, the connection topology is assumed to be either completely regular or completely random. But many biological, technological and social networks lie somewhere between these two extremes. Here we explore simple models of networks that can be tuned through this middle ground: regular networks 'rewired' to introduce increasing amounts of disorder. We find that these systems can be highly clustered, like regular lattices, yet have small characteristic path lengths, like random graphs. We call them 'small-world' networks, by analogy with the small-world phenomenon (popularly known as six degrees of separation. The neural network of the worm Caenorhabditis elegans, the power grid of the western United States, and the collaboration graph of film actors are shown to be small-world networks. Models of dynamical systems with small-world coupling display enhanced signal-propagation speed, computational power, and synchronizability. In particular, infectious diseases spread more easily in small-world networks than in regular lattices.

Animals↗

Trichromatic colour vision in New World monkeys.

Trichromatic colour vision depends on the presence of three types of cone photopigment. Trichromacy is the norm for all Old World monkeys, apes and humans, but in several genera of New World monkeys, colour vision is strikingly polymorphic. The difference in colour vision between these New and Old World primates results form differing arrangements of the pigment genes on the X chromosome. In Old World primates the three photopigments required for routine trichromatic colour vision are encoded by two or more X-chromosome pigment genes and an autosomal pigment gene. New World monkeys typically have only one X-chromosome pigment gene; multiple alleles allow different types of dichromatic colour vision and, in female heterozygous at this locus, variant forms of trichromatic colour vision. Here we report that multiple X-chromosome pigment genes and trichromatic colour vision are the norm for one genus of platyrrhine monkey, the howler monkey, Alouatta.

Alouatta↗

The prevalence of asthma appears to be inversely related to the incidence of typhoid and tuberculosis: hypothesis to explain the variation in asthma prevalence around the world.

The prevalence of asthma varies widely throughout the world. We now believe that asthma is due to airway inflammation caused by an imbalance of the T-lymphocytes in the airway. The atopy that drives asthma is due to a predominance of Th2 lymphocytes in the airway. This paper links the prevalence of asthma inversely to the prevalence of tuberculosis and enteric infection. We will argue that the reason we observe such marked variations in the prevalence of asthma around the world is the fact that in the developing world there is a survival advantage in the fetal immune response to mature from Th2 to Th1 lymphocyte predominant. A Th1 response is required to combat infectious diseases such as typhoid and tuberculosis. Data from the World Health Organization confirms that these two infectious diseases occur very rarely in those communities where the asthma is high. It may be that the clean and infection-free environment of Australia and New Zealand is responsible for the region of Oceania having the dubious honor of having the highest prevalence of asthma in the world.

Asthma↗

Cyclophilin A is required for TRIM5{alpha}-mediated resistance to HIV-1 in Old World monkey cells.

The peptidyl-prolyl isomerase cyclophilin A (CypA) embraces an exposed, proline-rich loop on HIV-1 capsid (CA) and renders reverse transcription complexes resistant to an antiviral activity in human cells. A CypA fusion with TRIM5 that is unique to New World owl monkeys also targets HIV-1 CA, but this interaction potently inhibits infection. A similar block to HIV-1 infection in Old World monkeys is attributable to the alpha isoform of the TRIM5 orthologue in these species. To determine whether HIV-1 restriction by Old World monkey TRIM5alpha is modulated by the CA-CypA interaction, RNA interference was used to disrupt CypA in cells from African green monkeys and rhesus macaques. HIV-1 infectivity increased in response to CypA knock-down to the same extent that it increased in response to TRIM5 knock-down. CypA knock-down eliminated the HIV-1 stimulatory effect of cyclosporin A (CsA), a competitive inhibitor of the CypA-CA interaction, or of CA mutants that block binding to CypA but caused no change in titer of retroviruses that don't interact with CypA. Simultaneous knock-down of both CypA and TRIM5 caused minimal additional increase in titer, suggesting that CypA inhibits HIV-1 replication in these cells because it is required for CA recognition by TRIM5alpha. Finally, CsA increased HIV-1 titer in otherwise nonrestrictive feline cells but only after these cells were transduced with Old World monkey TRIM5alpha. Thus, CypA is required for HIV-1 restriction by Old World monkey orthologues of TRIM5alpha.

Animals↗

DNA sequence support for a close phylogenetic relationship between some storks and New World vultures.

Nucleotide sequences from the mitochondrial cytochrome b gene were used to address a controversial suggestion that New World vultures are related more closely to storks than to Old World vultures. Phylogenetic analyses of 1-kb sequences from 18 relevant avian species indicate that the similarities in morphology and behavior between New World and Old World vultures probably manifest convergent adaptations associated with carrion-feeding, rather than propinquity of descent. Direct sequence evidence for a close phylogenetic alliance between at least some New World vultures and storks lends support to conclusions reached previously from DNA.DNA hybridization methods and detailed morphology-based appraisals, and it illustrates how mistaken assumptions of homology for organismal adaptations can compromise biological classifications. However, there was a lack of significant resolution for most other branches in the cytochrome b phylogenetic reconstructions. This irresolution is most likely attributable to a close temporal clustering of nodes, rather than to ceiling effects (mutational saturation) producing an inappropriate window of resolution for the cytochrome b sequences.

Animals↗

Malaria's Eve: evidence of a recent population bottleneck throughout the world populations of Plasmodium falciparum.

We have analyzed DNA sequences from world-wide geographic strains of Plasmodium falciparum and found a complete absence of synonymous DNA polymorphism at 10 gene loci. We hypothesize that all extant world populations of the parasite have recently derived (within several thousand years) from a single ancestral strain. The upper limit of the 95% confidence interval for the time when this most recent common ancestor lived is between 24,500 and 57,500 years ago (depending on different estimates of the nucleotide substitution rate); the actual time is likely to be much more recent. The recent origin of the P. falciparum populations could have resulted from either a demographic sweep (P. falciparum has only recently spread throughout the world from a small geographically confined population) or a selective sweep (one strain favored by natural selection has recently replaced all others). The selective sweep hypothesis requires that populations of P. falciparum be effectively clonal, despite the obligate sexual stage of the parasite life cycle. A demographic sweep that started several thousand years ago is consistent with worldwide climatic changes ensuing the last glaciation, increased anthropophilia of the mosquito vectors, and the spread of agriculture. P. falciparum may have rapidly spread from its African tropical origins to the tropical and subtropical regions of the world only within the last 6,000 years. The recent origin of the world-wide P. falciparum populations may account for its virulence, as the most malignant of human malarial parasites.

Africa↗

Euthanasia, physician-assisted suicide, and Christianity's positive relationship to the world.

This essay addresses the problem of communication between Christianity and the secular world in an area where the latter tends to oppose the moral norms endorsed by the former. How, in the interest of missionary outreach (and with which understandings of what such outreach involves) can the language barriers be bridged? Whereas the Roman Catholic natural law tradition posits a neutral common ground of (traditional or hermeneutical) rationality between Christianity and the world, an Ebeling- and Barth-modified Lutheranism engages in an argument ad hominem by seizing upon an admitted deficiency within that world, and by recommending Christianity for mending that deficiency. Both positions differ from the Evangelical claim that since that which the world politically values is derived from Christianity, it must remain subject to Christianity's moral legislation. An entirely different approach to the communication- and outreach-problem is taken by Orthodox Christianity: The gulf which separates it from the world is acknowledged, and the possibility of trans-gulf-traffic is referred to God's grace. It is only this latter model, however, which preserves Christianity's theological terms (such as "Scripture", "law", and "holiness") from common-ground-securing, deficiency-mending, or authority-imposing secularizing, and thus from compromising that very theological context into which communicative outreach endeavors were to invite.

Catholicism↗

The belief in a just world and perceptions of discrimination.

We examined the relationship between the belief in a just world and frequency of self-reported acts of personal discrimination. American adults with a strong belief in a just world reported fewer acts of personal discrimination against themselves than those with a weak belief in a just world. Among the various domains of discrimination, the belief in a just world correlated most strongly with religious discrimination. People with a strong belief in a just world felt that they would be less likely to provide special programs and funding based solely on a person's age; they did not feel that age discrimination was prevalent in American society.

Age Factors↗

Beliefs about the world and recovery from myocardial infarction.

Seventy male, Hindu Myocardial Infarction (MI) patients were interviewed twice--4 to 5 days after their first heart attack (Time 1) and a month after their first heart attack (Time 2). The patients' beliefs about the world (world beliefs), about the causes of the disease (causal beliefs), and about the factors contributing to their recovery (recovery beliefs) were measured. Each category of beliefs was concerned with three domains: karma, God, and just world (or self). The patients' physical and psychological recovery was evaluated. World and recovery beliefs were intercorrelated, but these beliefs were only weakly correlated with causal beliefs. Furthermore, world beliefs and recovery beliefs were positively associated with recovery from MI at both Time 1 and Time 2. Attribution of causality to God was negatively correlated with medical recovery, perceived recovery, and mood state at Time 2. This trend was in the reverse direction for attribution of causality to self.

Adaptation, Psychological↗

Religiosity and sphere-specific just world beliefs in 16- to 18-year-olds.

One hundred forty-three (31 female and 112 male) English school pupils, 16 to 18 years old, completed the Francis Scale of Attitudes towards Christianity (FSAC; Francis & Stubbs, 1987), the Global Belief in a Just World Scale (GBJWS; Lipkus, 1991), and the Multidimensional Belief in a Just World Scale (MBJWS; Furnham & Procter, 1992). The MBJWS yields three subscale scores: Sociopolitical Just World Beliefs (SJW), Interpersonal Just World Beliefs (IJW), and Personal Just World Beliefs (PJW). Scores on the FSAC were not associated with scores on the GBJWS, the SJW, or the IJW, but they were positively associated, albeit weakly, with scores on the PJW.

Adolescent↗

2nd World Water Forum.

The world is facing a water crisis. About one billion people lack access to safe water and three billion to appropriate sanitation. There will probably be two billion extra people on the planet by 2025; so while today's shortages are for fresh water and sanitation, tomorrow's are predicted to be for growing crops. Already, 10% of world food production is drawing down underground water faster than the recharge rates. Water also threatens to cause conflicts between regions--a state of affairs that is expected to worsen as this century progresses. To raise public awareness of these issues and pressurize politicians to act, the World Water Commission (WWC) held a Forum in March 2000 in The Hague. The Forum collected together a huge range of people from governments, non-government organizations (NGOs), workers for the environment and development, private sector water providers, trades unions and scientific institutes. They all discussed a document (World Water Vision: A Water Secure World, referred to as the Vision) drawn up by the WWC as a basis for action. The Forum culminated in a meeting of ministers from over 140 governments.

Conservation of Natural Resources↗

Comparison of National Death Index and World Wide Web death searches.

The authors used the National Death Index and a World Wide Web Internet site that searches the Social Security Administration master files of deaths to determine the mortality status of 1,000 US subjects from the College Alumni Health Study. Subjects were classified as definitely dead, possibly dead, or presumed alive. Of 246 definite deaths pinpointed by the National Death Index, the World Wide Web identified 94.7% of them. Of 438 men presumed alive according to the National Death Index, the World Wide Web identified 97.5% of them. However, the World Wide Web was not useful for identifying deaths of women. This study demonstrated that the World Wide Web may provide an alternative, inexpensive method of determining the mortality status of subjects in relatively small epidemiologic studies.

Databases, Factual↗

Ethnicity, ethics, and the deaf-world.

This article is concerned with ethical aspects of the relations between language minorities using signed languages (called the Deaf-World) and the larger societies that engulf them. The article aims to show that such minorities have the properties of ethnic groups, and that an unsuitable construction of the Deaf-World as a disability group has led to programs of the majority that discourage Deaf children from acquiring the language and culture of the Deaf-World and that aim to reduce the number of Deaf births-programs that are unethical from an ethnic group perspective. Four reasons not to construe the Deaf-World as a disability group are advanced: Deaf people themselves do not believe they have a disability; the disability construction brings with it needless medical and surgical risks for the Deaf child; it also endangers the future of the Deaf-World; finally, the disability construction brings bad solutions to real problems because it is predicated on a misunderstanding.

Cultural Diversity↗

Mitochondrial DNA analysis of Mongolian populations and implications for the origin of New World founders.

High levels of mitochondrial DNA (mtDNA) diversity were determined for Mongolian populations, represented by the Mongol-speaking Khalkha and Dariganga. Although 103 samples were collected across Mongolia, low levels of genetic substructuring were detected, reflecting the nomadic lifestyle and relatively recent ethnic differentiation of Mongolian populations. mtDNA control region I sequence and seven additional mtDNA polymorphisms were assayed to allow extensive comparison with previous human population studies. Based on a comparative analysis, we propose that indigenous populations in east Central Asia represent the closest genetic link between Old and New World populations. Utilizing restriction/deletion polymorphisms, Mongolian populations were found to carry all four New World founding haplogroups as defined by WALLACE and coworkers. The ubiquitous presence of the four New World haplogroups in the Americas but narrow distribution across Asia weakens support for GREENBERG and coworkers' theory of New World colonization via three independent migrations. The statistical and geographic scarcity of New World haplogroups in Asia makes it improbable that the same four haplotypes would be drawn from one geographic region three independent times. Instead, it is likely that founder effects manifest throughout Asia and the Americas are responsible for differences in mtDNA haplotype frequencies observed in these regions.

Asian People↗

Follow-up studies of World War II and Korean war prisoners. II. Morbidity, disability, and maladjustments.

US Army veterans taken prisoner (POW's) in World War II and in the Korean War are compared with controls as to hospital admissions from 1946 to 1965 (1954-1965 for Korean War POW's), and as to symptoms, disability, and maladjustments in 1966-1967. Sequelae of the POW experience are both somatic and psychiatric, and are of greatest extent and severity among Pacific World War II POW's. Among European World War II POW's only psychiatric sequelae are apparent. Somatic sequelae were most prevalent in the early years after liberation, but for Pacific World War II POW's they persist in the form of higher hospital admission rates for many specific causes in the most recent period. Nevertheless, persistent psychiatric sequelae (especially psychoneurosis but also schizophrenia) are the more notable and pervasive for both Pacific World War II POW's and Korean War POW's as seen not only in elevated hospital admission rates but also in VA disability awards and in symptoms reported on the cornell Medical Index Health Questionnaire. The excess morbidity appears to correlate well with retrospective accounts of weight-loss and nutritional deficiency diseases and symptoms during the POW period.

Aged↗

Patterns and problems of deliberate self-poisoning in the developing world.

Deliberate self-harm is a major problem in the developing world, responsible for around 600 000 deaths in 1990. The toxicity of available poisons and paucity of medical services ensure that mortality from self-poisoning is far greater in the tropics than in the industrialized world. Few data are available on the poisons most commonly used for self-harm in different parts of the world. This paper reviews the literature on poisoning, to identify the important poisons used for self-harm in these regions. Pesticides are the most important poison throughout the tropics, being both common and associated with a high mortality rate. In some regions, particular pesticides have become the most popular method of self-harm, gaining a notoriety amongst both health-care workers and public. Self-poisoning with medicines such as benzodiazepines and antidepressants is common in urban areas, but associated with few deaths. The antimalarial chloroquine appears the most significant medicine, self-poisoning being common in both Africa and the Pacific region, and often fatal. Paracetamol (acetaminophen) is used in many countries but in few has it reached the popularity typical of the UK. Domestic and industrial chemicals are responsible for significant numbers of deaths and long-term disabilities world-wide. Self-poisoning with plant parts, although uncommon globally, is locally popular in some regions. Few of these poisons have specific antidotes. This emphasizes the importance of determining whether interventions aimed at reducing poison absorption actually produce a clinical benefit, reducing death and complication rates. Future research to improve medical management and find effective ways of reducing the incidence of self-harm, together with more widespread provision of interventions proven to be effective, could rapidly reduce the number of deaths from self-poisoning in the developing world.

Adolescent↗

Considering body mass differences, who are the world's strongest women?

PURPOSE: Allometric modeling (AM) has been used to determine the world's strongest body mass-adjusted man. Recently, however, AM was shown to demonstrate body mass bias in elite Olympic weightlifting performance. A second order polynomial (2OP) provided a better fit than AM with no body mass bias for men and women. The purpose of this study was to apply both AM and 2OP models to women's world powerlifting records (more a function of pure strength and less power than Olympic lifts) to determine the optimal model approach as well as the strongest body mass-adjusted woman in each event. METHODS: Subjects were the 36 (9 per event) current women world record holders (as of Nov., 1997) for bench press (BP), deadlift (DL), squat (SQ), and total (TOT) lift (BP + DL + SQ) according to the International Powerlifting Federation (IPF). RESULTS: The 2OP model demonstrated the superior fit and no body mass bias as indicated by the coefficient of variation and residuals scatterplot inspection, respectively, for DL, SQ, and TOT. The AM for these three lifts, however, showed favorable bias toward the middle weight classes. The 2OP and AM yielded an essentially identical fit for BP. CONCLUSIONS: Although body mass-adjusted world records were dependent on the model used, Carrie Boudreau (U.S., 56-kg weight class), who received top scores in TOT and DL with both models, is arguably the world's strongest woman overall. Furthermore, although the 2OP model provides a better fit than AM for this elite population, a case can still be made for AM use, particularly in light of theoretical superiority.

Bias↗