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Considerable ambiguity remains over the extent and nature of millennial/centennial-scale climate instability during the Last Interglacial (LIG). Here we analyse marine and terrestrial proxies from a deep-sea sediment sequence on the Portuguese Margin and combine results with an intensively dated Italian speleothem record and climate-model experiments. The strongest expression of climate variability occurred during the transitions into and out of the LIG. Our records also document a series of multi-centennial intra-interglacial arid events in southern Europe, coherent with cold water-mass expansions in the North Atlantic. The spatial and temporal fingerprints of these changes indicate a reorganization of ocean surface circulation, consistent with low-intensity disruptions of the Atlantic meridional overturning circulation (AMOC). The amplitude of this LIG variability is greater than that observed in Holocene records. Episodic Greenland ice melt and runoff as a result of excess warmth may have contributed to AMOC weakening and increased climate instability throughout the LIG.

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OBJECTIVES: To identify breed-associated risk factors for urolithiasis in dogs from the UK. METHODS: Records of all canine uroliths submitted to Hills Pet Nutrition UK for analysis at the University of Minnesota Urolith Centre over 10 years (1997 to 2006) were reviewed. The results, along with the request forms completed by the submitting veterinarian, were analysed. The most commonly affected breeds, age and gender of the dogs were identified for each of the most common types of uroliths (struvite, calcium oxalate, urate, cystine and mixed). Pearson's chi-squared tests were performed to assess whether certain breeds of dogs were over-represented relative to a reference population (from an insurance database). RESULTS: The records of 14,008 urolith submissions were analysed. The relative frequency of struvite remained stable over time, whereas calcium oxalate decreased over the study period. Breeds found to be significantly over-represented for calcium oxalate uroliths included the Chihuahua, miniature poodle and Yorkshire terrier. Staffordshire bull terriers and English bulldogs were at increased risk for cystine uroliths. CLINICAL SIGNIFICANCE: Associations between breed, gender, age and urolith formation were similar to those reported elsewhere. However, temporal trends and novel breed predispositions were identified.

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During the last two decades, there has been an explosive increase in the number of MR investigations involving genetically manipulated mice and rats. Many of the animal studies are performed in a more or less clinical environment, where whole-body MR scanners are the only option available. The quality and acquisition time of MR images have improved with the development of novel RF coil technologies. This communication describes the construction of a small inductively coupled capacitive overlap transmit-receive MR coil for imaging of small animals and objects in a clinical MR scanner. The MR coil presented here is a modified version of the bridged loop-gap coil and consists of two tube-shaped coupled resonance circuits, where the primary circuit partly encapsulates the imaging (secondary) circuit. By rotating the concentric primary coil relative to the secondary coil tuning over a range of several hundred kilohertz is obtained. The coil performance was characterized experimentally by acquiring high-resolution anatomical, diffusion and perfusion MR images as well as the acquisition of proton spectra of a mouse tumour.

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Several species of freshwater unionid mussels in the genus Lampsilis exhibit a remarkable reproductive strategy. Female mussels of these species enclose their larvae in a minnow-like lure, called a 'superconglutinate', to attract piscivorous fishes. When a fish attempts to ingest the superconglutinate the lure ruptures and the larvae are released to parasitize the fish. Of the four species of mussel which exhibit this strategy and are endemic to the Gulf Coast drainages of the southeastern United States, three are protected under the Endangered Species Act, and one is recognized as imperiled. Phylogenetic analysis of nucleotide sequences of the mitochondrial 16S ribosomal RNA and the first subunit of the cytochrome oxidase c genes was conducted on 18 individual specimens representing these four species and six outgroup taxa. Phylogenetic analyses of these data support the monophyly of the superconglutinate-producing mussels, and indicates a strong geographical component to the data. The zoogeographic patterns of the four taxa included in the study are congruent with those seen in freshwater vertebrates, and are consistent with a vicariant pattern resulting from fluctuations in sea level during the Pleistocene. Despite the strong geographical structuring of the data, only one species, Lampsilis subangulata, was recovered as monophyletic. The authors attribute the lack of support for the monophyly of the remaining species to insufficient sequence variation and the recent origin of the ancestor of these taxa. Based on these data, any future captive breeding projects aimed at augmenting or re-establishing populations should do so only from the appropriate source populations so as to maintain the genetic integrity of these nascent species.

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Evidence is growing that hydrothermal venting occurs not only along mid-ocean ridges but also on old regions of the oceanic crust away from spreading centres. Here we report the discovery of an extensive hydrothermal field at 30 degrees N near the eastern intersection of the Mid-Atlantic Ridge and the Atlantis fracture zone. The vent field--named 'Lost City'--is distinctly different from all other known sea-floor hydrothermal fields in that it is located on 1.5-Myr-old crust, nearly 15 km from the spreading axis, and may be driven by the heat of exothermic serpentinization reactions between sea water and mantle rocks. It is located on a dome-like massif and is dominated by steep-sided carbonate chimneys, rather than the sulphide structures typical of 'black smoker' hydrothermal fields. We found that vent fluids are relatively cool (40-75 degrees C) and alkaline (pH 9.0-9.8), supporting dense microbial communities that include anaerobic thermophiles. Because the geological characteristics of the Atlantis massif are similar to numerous areas of old crust along the Mid-Atlantic, Indian and Arctic ridges, these results indicate that a much larger portion of the oceanic crust may support hydrothermal activity and microbial life than previously thought.

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This study explored whether 3-mo.-old male infants' differential vocal response to mother vs a female stranger, which has been related to cognitive and academic functioning up to 12 years of age, is also related to adult development. Of the 12 subjects who had been seen from infancy through 12 years, 10 were located at Ages 21 and 28 years and were asked about their high school grade point average, scores on the SAT, years of schooling, emotional adjustment, substance abuse, and if they were in a stable relationship by the age 28. Responses showed 3-mo.-olds' differential vocal response was related positively to high school grade point average, scores on the SAT, years of completed education by age 28, and stability of relationship by age 28, and negatively related to substance abuse. No relationship was found between differential vocal response and reported emotional problems. Results suggest that early infant social interactions may be linked to adult development or adjustment.

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Syntactic priming of Chinese nouns and verbs was investigated in word recognition (cued shadowing of auditory targets) and production (picture naming). Disyllabic compound words were presented after syntactically congruent, incongruent, or neutral auditory contexts, with a zero delay between offset of the context and onset of the target. Significant priming was observed in both tasks, including facilitation as well as inhibition. Post hoc analyses showed that reaction times were also affected by sublexical variables that are especially relevant for Chinese, including syllable density (number of word types and tokens in the language with the same first or second syllable) and semantic transparency (whether the meaning of the whole word is predictable from the separate meanings of the two syllables within the compound). These patterns suggest competitive effects at the sublexical level. Implications for interactive models of lexical access are discussed.

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The effect of sentence priming on picture naming was investigated across the lifespan, from age 3 to 87 years. Names that are normally acquired before 3 years of age were presented in auditory contexts that were semantically congruent, incongruent, or neutral in relation to each picture and its name. Sentential priming was present at all age levels. Facilitation (neutral vs. congruent) was significantly by 4 years of age and did not vary significantly with age. Interference (incongruent vs. neutral) was significant at all age levels, but changed nonmonotonically with age (largest in the youngest children, stable from young adulthood through age 70, with a small increase in the oldest participants). We conclude that picture naming is a useful tool for the investigation of sentential priming effects across the lifespan and that it can reveal potentially interesting developmental changes in the effects of sentential context on word retrieval.

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European adolescents' use of mass media differs significantly by gender, family life, social economic status, and education, according to recent studies. For example, boys are more likely than girls to have a television in their own room, and content preferences are dramatically different. Recent studies also suggest that family dynamics may change as new media technologies are introduced. In some studies, the mother's educational status has been more directly related to patterns of electronic media use than the father's, and adolescents' commitment to school has been shown to predict music preferences. To make meaningful generalizations about adolescents and the media in the future, these and other mediating factors, including ethnicity and cognitive development, must be considered.

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A study of 147 mother-infant dyads revealed that the most talkative mothers did not allow their infants to initiate many conversations. The least talkative mothers ignored many of their infants' vocalizations. Mothers in the mid-level talking range demonstrated the greatest reciprocity, allowing their infants to initiate more conversations.

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The majority of Middle American cichlids are placed in the informal assemblage 'Cichlasoma.' The group is divided into eight sections which appear to be based primarily on trophic morphology. Although several members of 'Cichlasoma' have been used in ecomorphological, behavioral, and biogeographic studies, no phylogenetic hypotheses for the group exist. In an attempt to develop a better understanding of the phylogenetic relationships of 'cichlasomine' cichlids, we examined the evolution of the trophic specialization, substratum-sifting, in two sections, 'Cichlasoma (Thorichthys)' and 'C. (Amphilophus),' to determine whether the trait reflects common ancestry. We sequenced the complete mitochondrial cytochrome b gene for 19 cichlids representing six sections of 'Cichlasoma,' and representatives of other Neotropical Cichlidae. Additional cichlid, and noncichlid outgroup sequences were included for a total of 22 taxa. The molecular phylogeny supports the recognition of the section 'C. (Thoricthys)' as a natural group, and we place those cichlids in the genus Thorichthys. The phylogeny also depicts 'C. (Amphilophus)' as paraphyletic, with substratum-sifters and generalized predators forming separate nonsister clades. We recommend that the substratum-sifting clade of the section 'C. (Amphilophus)' be placed in the resurrected genus Astatheros. The generalized predator clade of 'C. (Amphilophus)' contains only two species, 'C. (A.) citrinellum' and 'C. (A.) labiatum,' which we place in the genus Amphilophus. The phylogenetic hypotheses generated indicate that the substratum-sifting genera Thorichthys and Amphilophus do not share a common ancestor. Reconstruction of the evolution of substratum-sifting is equivocal, requiring either the independent evolution of the trait on two separate occasions or its presence in a more inclusive clade and subsequent loss in nonsubstratum sifting species.

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OBJECTIVES: Approximately 3.2 million children live with their grandparents or other relatives-a 40% increase in 10 years. This article presents selected findings from an exploratory study of the experience of 71 African-American women raising their grandchildren because of the crack epidemic. METHODS: The study was designed to describe the caregivers' self-reported physical and emotional health status and health-care-related behaviors through a combination of qualitative and quantitative data collected during two in-home interviews. RESULTS: Most respondents rated their health as good or fair, with little change over the previous year, or since caregiving began. Employed women were more likely not only to rate their health as excellent or good, but also to report that their health had deteriorated over the previous year. Other subgroups showing evidence of deteriorating health were those caring for several grandchildren and great-grandmothers. Caregivers without a confidante reported a positive health change. Although 80% of the sample reported receiving regular health care, one third had not been to the doctor in 3 years. Half reported breaking a medical appointment in the last year, most often because of caregiving demands. CONCLUSIONS: These findings have relevance for physicians and other health-care providers because they suggest that many grandparent caregivers may be or soon become the "hidden patients" of the crack cocaine epidemic.

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Full-term infants at both 2 and 3 months and preterm ones at 3 months from due date vocalized more to mother than to a stranger and gazed more at a stranger than the mother. Preterm infants at 3 months from birth, but 6 weeks from due date, did not show differential responding by any mode, indicating the importance of maturational rather than environmental factors in these behaviors.

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This article presents a case study of the effective synergy of health education inquiry, community collaboration, and policy advocacy. Using the Grandparent Caregiver Study as the example, the authors focus on key methodological decisions that enabled them to incorporate research, education, and advocacy activities into an ever-growing project on a modest budget. The study itself centered on two in-depth interviews with each of 71 African American grandmothers raising young grandchildren due to the crack cocaine epidemic in Oakland, California. The case study demonstrates ways in which health education research can increase the efficacy of individuals and disenfranchised groups to define problems, voice their concerns, and advocate for more just and healthy public policies. Through discussion of the authors' methods and activities, they suggest strategies through which research participants, service providers, and policymakers can work together to bring a new issue to the policy arena through a collaborative and empowering research process.

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A survey of hydrothermal activity along the superfast-spreading (approximately 150 millimeters per year) East Pacific Rise shows that hydrothermal plumes overlay approximately 60 percent of the ridge crest between 13 degrees 50' and 18 degrees 40'S, a plume abundance nearly twice that known from any other rige portion of comparable length. Plumes were most abundant where the axial cross section is inflated and an axial magma chamber is present. Plumes with high ratios of volatile ((3)He, CH(4), and H(2)S) to nonvolatile (Mn and Fe) species marked where hydrothermal circulation has been perturbed by recent magmatic activity. The high proportion of volatile-rich plumes observed implies that such episodes are more frequent here than on slower spreading ridges.

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Changes in family and friendship networks of 71 African-American grandmothers raising grandchildren as a consequence of the crack-cocaine epidemic are examined. Despite continued strong social ties, many of the women reported decreased contact with family and friends other than confidantes and a decline in marital satisfaction. Implications of the findings for research, policy, and practice are discussed.

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Community interventions and service programs for grandparents raising grandchildren are being identified and tracked through the Brookdale Grandparent Caregiver Information Project. Based on the first year's examination of 124 such programs, an overview of community intervention effort is provided, with special attention to support groups and comprehensive multi-service programs for grandparent caregivers. Lack of funding and institutional support, and the consequent inability to provide child care, were among key obstacles faced, while sponsorship by health and social service agencies often played a vital role in providing in-kind support and part-time professional staff.

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The conceptions of 53 American and 54 Greek infants were categorized as planned or unplanned on the basis of mothers' reports. At age three months in both cultural groups, infants in the planned category showed higher levels of cognitive processing and attachment to their mothers than did infants in the unplanned category, as shown by their differential vocal responses to mothers versus a female stranger.

PIP: Female investigators observed 107 full-term, normal, home-reared, 3-month-old infants in their homes with their mothers present to determine whether the babies whose mothers planned their pregnancy had a higher differential vocal response to their mothers than to a female stranger than did babies whose mothers did not plan their pregnancy. They compared the reactions of 53 infants from Los Angeles, California, with those of 54 infants from Athens, Greece. Regardless of culture, infants who were a result of a planned pregnancy had a higher differential vocal response score and vocalized significantly more in response to their mothers than to the stranger than did infants who were the result of an unplanned pregnancy (p .01 and .001, respectively). These findings demonstrated the 3-month-old infant's cognitive capacity to differentiate the mother from the stranger and their preference for their mother. They also suggested that the mother's feelings toward the baby do indeed contribute to the quality of the relationship and the degree of reciprocity with the mother. Further, it appears that children whose conception is unplanned are at greater risk for maternal rejection and subsequent psychopathology than children whose conception is planned. Thus, psychologists and psychiatrists should study the degree of bonding between mother and child and, if required, try to strengthen the bonding in cases where the mother did not plan the child's conception and psychopathology exists.

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