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We report K-Pg-age deposits in Baja California, Mexico, consisting of terrestrial and shallow-marine materials re-sedimented onto the continental slope, including corals, gastropods, bivalves, shocked quartz grains, an andesitic tuff with a SHRIMP U-Pb age (66.12 ± 0.65 Ma) indistinguishable from that of the K-Pg boundary, and charred tree trunks. The overlying mudstones show an iridium anomaly and fungal and fern spores spikes. We interpret these heterogeneous deposits as a direct result of the Chicxulub impact and a mega-tsunami in response to seismically-induced landsliding. The tsunami backwash carried the megaflora offshore in high-density flows, remobilizing shallow-marine fauna and sediment en route. Charring of the trees at temperatures up to > 1000 °C took place in the interval between impact and arrival of the tsunami, which on the basis of seismic velocities and historic analogues amounted to only tens of minutes at most. This constrains the timing and causes of fires and the minimum distance from the impact site over which fires may be ignited.

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Sediment, nutrients, organic carbon and pollutants are funnelled down submarine canyons from continental shelves by sediment-laden flows called turbidity currents, which dominate particulate transfer to the deep sea. Post-glacial sea-level rise disconnected more than three quarters of the >9000 submarine canyons worldwide from their former river or long-shore drift sediment inputs. Existing models therefore assume that land-detached submarine canyons are dormant in the present-day; however, monitoring has focused on land-attached canyons and this paradigm remains untested. Here we present the most detailed field measurements yet of turbidity currents within a land-detached submarine canyon, documenting a remarkably similar frequency (6 yr-1) and speed (up to 5-8 ms-1) to those in large land-attached submarine canyons. Major triggers such as storms or earthquakes are not required; instead, seasonal variations in cross-shelf sediment transport explain temporal-clustering of flows, and why the storm season is surprisingly absent of turbidity currents. As >1000 other canyons have a similar configuration, we propose that contemporary deep-sea particulate transport via such land-detached canyons may have been dramatically under-estimated.

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The purpose of this prospective and observational design study was to assess the feasibility of using a pedometer and step log to explore level of physical activity (PA) and to assess motivation to be physically active in adults with schizophrenia. Descriptive statistics were used to analyse data of 7 male and 5 female subjects. Pedometer data indicated that subjects walked an average of 4731.03 (±3318.19) steps and 5002.58 (±3041.03) during the first week and second week of the study, respectively. A minimum 30-min walk was recorded on an average of 3.67 (±1.82) days (week one) and 4.5 (±1.88) days (week two). Step logs, inconsistently maintained by subjects, were not able to be analysed. Examination of the Motives for Physical Activity Measure-Revised (MPAM-R) at baseline indicates that exercise fitness and body appearance were subjects' primary motives for PA participation. Study findings indicate that it is feasible to use a pedometer to monitor the level of PA. However, maintenance of a concurrent step log requires further consideration to determine realistic outcomes. Extrinsically focused motivations for PA in this study sample may predict low PA adherence.

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The purpose of this prospective and observational study was to explore medication-taking behaviours in community-based young adults with schizophrenia using an electronic monitoring system and patient self-report questionnaires. The Medication Event Monitoring System (MEMS®), the Index for Medication Adherence (IMA) and the Brief Evaluation of Medication Influences and Beliefs (BEMIB) measured medication-taking behaviours. Data were collected at baseline, 4 and 8 weeks. Descriptive statistics were used in analysis. A total of 11 subjects were recruited; one dropped out. Five were male, and five were female. Average age was 32.64 (SD = 5.70) years. Four (40%) were White people; six (60%) were non-White people. The average number of medications treating schizophrenia was 1.9 (SD = 0.57). MEMS® identified 71.77% (SD = 30.47) dose adherence and 55.92% (SD = 31.27) day adherence. Most subjects took medications irregularly (early, late or missing). The BEMIB demonstrated that 50%, 20% and 30% of subjects considered themselves to be adherent to their medications at baseline, 4 weeks and 8 weeks, while the IMA reported 90%, 90% and 80% at baseline, 4 weeks and 8 weeks, respectively. Regarding the observed discrepancies between patients' reports and their actual medication-taking behaviours, clinical implications were discussed. Effective interventions improving medication adherence in schizophrenia are needed for practice and for future studies.

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MR diffusion/perfusion mismatch may help identify patients for acute stroke treatment, but mixed results from clinical trials suggest that further evaluation of the mismatch concept is required. To work effectively, mismatch should predict prognosis on arrival at hospital. We assessed mismatch duration and associations with functional outcome in acute stroke. We recruited consecutive patients with acute stroke, recorded baseline clinical variables, performed MR diffusion and perfusion imaging and assessed 3-month functional outcome. We assessed practicalities, agreement between mismatch on mean transit time (MTT) or cerebral blood flow (CBF) maps, visually and with lesion volume, and the relationship of each to functional outcome. Of 82 patients starting imaging, 14 (17%) failed perfusion imaging. Overall, 42% had mismatch (56% at <6 h; 41% at 12-24 h; 23% at 24-48 h). Agreement for mismatch by visual versus volume assessment was fair using MTT (kappa 0.59, 95% CI 0.34-0.84) but poor using CBF (kappa 0.24, 95% CI 0.01-0.48). Mismatch by either definition was not associated with functional outcome, even when the analysis was restricted to just those with mismatch. Visual estimation is a reasonable proxy for mismatch volume on MTT but not CBF. Perfusion is more difficult for acute stroke patients than diffusion imaging. Mismatch is present in many patients beyond 12 h after stroke. Mismatch alone does not distinguish patients with good and poor prognosis; both can do well or poorly. Other factors, e.g. reperfusion, may influence outcome more strongly, even in patients without mismatch.

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BACKGROUND: The mismatch between perfusion and diffusion lesions on magnetic resonance perfusion-weighted imaging (PWI)/diffusion-weighted imaging (DWI) may help identify patients for thrombolysis. Evidence underlying this hypothesis was assessed. METHODS: All papers describing magnetic resonance PWI/DWI findings in patients with acute ischaemic stroke, and their functional and/or radiological outcome at 1 month, with or without thrombolysis were systematically reviewed. RESULTS: 11 papers fulfilled the inclusion criteria. Among these, there were 5 different mismatch definitions and at least 7 different PWI methods. Only 3 papers including 61 patients with and 18 without mismatch provided data on mismatch, outcome and influence of thrombolysis. Mismatch (v no mismatch) without thrombolysis was associated with a non-significant twofold increase in the odds of infarct expansion (odds ratio (OR) 2.2, 95% confidence interval (CI) 0.34 to 14.1), which did not change with thrombolysis (OR 2.0, 95% CI 0.37 to 10.9). Half of the patients without mismatch also had infarct growth (with or without thrombolysis). No data were available on functional outcome. CONCLUSIONS: Standardised definitions of mismatch and perfusion are needed. Infarct growth may occur even in the absence of mismatch. Currently, data available on mismatch are too limited to guide thrombolysis in routine practice. More data are needed from studies including patients with and without mismatch, and randomised treatment allocation, to determine the role of mismatch.

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BACKGROUND: There are wide variations in survival after cardiopulmonary resuscitation. The aim of this survey was to describe how equipment provision of resuscitation trolleys was deployed in a range of clinical ward areas. METHODS: The equipment in randomly selected resuscitation trolleys in all 14 South West Thames Region hospitals was surveyed. The gold standard for equipment provision was referenced from the document CPR Guidance for Clinical Practice and Training in Hospital. RESULTS: There were significant differences in the provision of circulation equipment (p = 0.004) and in the rates of drug items present (p = 0.001). There was no significant difference in provision of airways equipment (p = 0.24) or immediate access items (p = 0.55). CONCLUSIONS: There are variations in the provision of resuscitation equipment in many clinical areas. Hospitals need to review the procedures for ensuring adequate provision of resuscitation equipment in all clinical areas.

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A realistic estimation of the cost of government campaigns to control rinderpest and contagious bovine pleuropneumonia is essential in order to determine profitable fees for private veterinarians with a health mandate in Senegal. A cost analysis of a vaccination campaign, organised by the Veterinary Services in Senegal between 1995 and 1996, involving 547,735 cattle, was conducted. Revenue and total costs were 50 CFA francs and 110 +/- 37 CFA francs per head, respectively. Staff-related costs accounted for 39.41% +/- 7.62% of the total cost. The gross and net margins corresponded to the average subsidies of 42 +/- 27 CFA francs and 60 +/- 37 CFA francs, respectively. Simulations showed better relative efficiency for private veterinarians who vaccinate at a price of between 97 and 84 CFA francs per head. Economies of scale varied from 8 to 13 CFA francs per head when the vaccination team increased the number of animals initially vaccinated (16,000 head) by 25% and 44%, respectively. This indicates that a fee of 125 CFA francs per head should guarantee the profitability of compulsory vaccination for private veterinarians.

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BACKGROUND: After the age of 60, isolated cardiac amyloidosis is four times more common among blacks than whites in the United States; 3.9 percent of blacks are heterozygous for an amyloidogenic allele of the normal serum carrier protein transthyretin in which isoleucine is substituted for valine at position 122 (Ile 122). We hypothesized that the high prevalence of transthyretin Ile 122 is at least partially responsible for the increased frequency of senile cardiac amyloidosis among blacks. METHODS: Paraffin blocks of cardiac tissue were obtained from an earlier study of 52,370 autopsies in Los Angeles and were examined by immunohistochemical and DNA analyses. Samples were available from 32 of 55 blacks and 20 of 78 whites over 60 years of age with isolated cardiac amyloidosis and from two control groups (228 cases). RESULTS: Transthyretin amyloidosis was identified in 31 of the 32 cardiac-tissue samples from the black patients and in 19 of the 20 samples from the white patients. Six of the 26 analyzable DNA samples (23 percent) from the black patients and none of the 19 samples from the white patients were heterozygous for the Ile 122 variant. Four of 125 DNA samples obtained at autopsy (3.2 percent) from a second, more recent, age-matched cohort of blacks without amyloidosis at the same institution were heterozygous for the transthyretin Ile 122 allele. On reexamination the cardiac tissue from these four patients contained small amounts of amyloid not detected at the initial autopsies. All subjects with the Ile 122 variant had ventricular amyloid. CONCLUSIONS: The assessment of elderly black patients with unexplained heart disease should include a consideration of transthyretin amyloidosis, particularly that related to the Ile 122 allele.

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An epidemiological survey was carried out in the Trarza and Brakna regions of the Senegal River valley in Mauritania prior to implementation of a program to control intestinal parasitic infection and schistosomiasis. A total of 1297 school children between the ages of 5 and 12 years from a randomized selection of villages in the region were examined to determine the prevalence and intensity of intestinal parasitic infections and schistosomiasis. Overall prevalence was 38.1% for intestinal parasitic infection, 7.1% for intestinal schistosomiasis, and 17.1% for urinary schistosomiasis. Analysis of weight and height as indicators of nutritional status indicated that 40.9% of the children examined were under the 10th percentile of the weight-for-height indicator and that there was a statistically significant correlation between malnutrition, diarrhea, and intestinal parasitic infection (p < 0.0001). Measurement of hemoglobin levels showed that 50.4% of children were anemic (hemoglobin level < 11 g/dl) and that there was a correlation between anemia and infection by Schistosoma haematobium. This is the first epidemiological survey on intestinal parasitic infections in Mauritania and the first study on Schistosoma mansoni on the Mauritanian side of the Senegal River. Findings suggest not only that implementation of a program to control intestinal parasitic infection and schistosomiasis is needed in the region but also that it should be associated with a food/iron supplementation program and growth monitoring.

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The transthyretin (TTR) Ile 122 variant is associated with cardiac amyloidosis in individuals of African descent. To determine the prevalence of the allele encoding TTR Ile 122 in African-Americans, we have used PCR and restriction analysis to test DNA from African-Americans from various geographic areas, and found an allele frequency of 66/3376 (0.020), which is higher than the value we previously reported in a much smaller pilot study. Our data indicate that this TTR variant is present at equal frequency in African-Americans throughout the U.S., and suggest that this mutation may be a common, often unrecognized cause of cardiac disease in African-Americans.

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To define some methodological factors that could affect the measurement of the esophageal clearance, we used three different protocols, on 41 healthy control subjects. In 20 subjects, we studied the influence of a naso-esophageal probe on the frequency of swallowing. We observed a significant (44 +/- 5%) decrease in the frequency of spontaneous swallows after 15 minutes, with stabilization after this 15 minute period of adaptation. In 11 subjects, we studied the influence of the pH of the esophageal content on esophageal clearance. We found an exponential relationship between the esophageal clearance (C) expressed in minutes and the initial pH of the lumen contents: C = 43.3 exp (-0.54 pH) In 10 other subjects, we studied the influence of the volume of the esophageal contents on esophageal clearance. We found no influence for volumes less than 30 ml and a significant increase of clearance for volumes greater than 30 ml. In summary, this study of the effects of methodological factors on esophageal clearance: Gives new information about the "accommodation phase" of the esophagus after distension by a naso-gastric probe; Allows us to propose a new quantitative method for evaluation of esophageal clearance Shows the small importance of the ingested volume.

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All too often nursing standards have been viewed as a cumbersome paperwork task with little day-to-day practical relevance. Using a matrix approach that incorporates nursing role functions and the nursing process, the authors developed a model that provides the basis for job descriptions, performance appraisals, peer review, and quality management activities.

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Mutations in the protein transthyretin cause amyloidosis involving the heart, peripheral nerves, and other organs. A family from West Virginia developed an unusually aggressive form of widespread transthyretin amyloidosis. Single-strand conformation polymorphism analysis revealed a variant in the transthyretin gene, which was found on sequencing to be a T----C transversion at position 2 of codon 55, corresponding to a Leu----Pro substitution. The variant sequence was confirmed by restriction analysis and polymerase chain reaction (PCR)-primer introduced restriction analysis.

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This study was intended to assess the presence of antibodies to BCG: immunoglobulin G (IgG) and immunoglobulin M (IgM) in three homogenous african populations: 76 tuberculous patients, 55 adult healthy subjects and 46 newborn. We have used an indirect immuno-peroxidase reaction. Tuberculous patients were clearly distinguished from the other two groups by raised IgG titres, associated with severe clinical and radiological features. In the control population, the IgG anti-BCG were also present, but to a lesser degree. The IgM anti-BCG were seen in high titres (greater than 20 in this study) in healthy adults and patients. The two populations differed significantly (p less than 0.001), nevertheless some healthy adults achieved IgM titres comparable with tuberculous patients. This simple test could be an interesting contributory factor in cases of diagnostic difficult and enables a serological assessment of patients having BCG therapy.

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