Reconstructing 4000 years of mass movement and tsunami history in a deep peri-Alpine lake (Lake Geneva, France-Switzerland)

The study of mass movements in lake sediments provides insights into past natural hazards at historic and prehistoric timescales. Sediments from the deep basin of Lake Geneva reveal a succession of six large-scale (volumes of 22 × 106 to 250 × 106 m3) mass-transport deposits, associated with five mass-movement events within 2600 years (4000 cal bp to 563 ad). The mass-transport deposits result from: (i) lateral slope failures (mass-transport deposit B at 3895 ± 225 cal bp and mass-transport deposits A and C at 3683 ± 128 cal bp); and (ii) Rhône delta collapses (mass-transport deposits D to G dated at 2650 ± 150 cal bp, 2185 ± 85 cal bp, 1920 ± 120 cal bp and 563 ad, respectively). Mass-transport deposits A and C were most probably triggered by an earthquake, whereas the Rhône delta collapses were likely to be due to sediment overload with a rockfall as the external trigger (mass-transport deposit G, the Tauredunum event in 563 ad known from historical records), an earthquake (mass-transport deposit E) or unknown external triggers (mass-transport deposits D and F). Independent of their origin and trigger mechanisms, numerical simulations show that all of these recorded mass-transport deposits are large enough to have generated at least metre-scale tsunamis during mass movement initiation. Since the Tauredunum event in 563 ad, two small-scale (volumes of 1 to 2 × 106 m3) mass-transport deposits (H and I) are present in the seismic record, both of which are associated with small lateral slope failures. Mass-transport deposits H and I might be related to earthquakes in Lausanne/Geneva (possibly) 1322 ad and Aigle 1584 ad, respectively. The sedimentary record of the deep basin of Lake Geneva, in combination with the historical record, show that during the past 3695 years, at least six tsunamis were generated by mass movements, indicating that the tsunami hazard in the Lake Geneva region should not be neglected, although such events are not frequent with a recurrence time of 0·0016 yr−1.

Thermal and collisional history of Tishomingo iron meteorite: More evidence for early disruption of differentiated planetesimals

Tishomingo is a chemically and structurally unique iron with 32.5 wt.% Ni that contains 20% residual taenite and 80% martensite plates, which formed on cooling to between -75 and -200 °C, probably the lowest temperature recorded by any meteorite. Our studies using transmission (TEM) and scanning electron microscopy (SEM), X-ray microanalysis (AEM) and electron backscatter diffraction (EBSD) show that martensite plates in Tishomingo formed in a single crystal of taenite and decomposed during reheating forming 10-100 nm taenite particles with ∼50 wt.% Ni, kamacite with ∼4 wt.%Ni, along with martensite or taenite with 32 wt.% Ni. EBSD data and experimental constraints show that Tishomingo was reheated to 320-400 °C for about a year transforming some martensite to kamacite and to taenite particles and some martensite directly to taenite without composition change. Fizzy-textured intergrowths of troilite, kamacite with 2.7 wt.% Ni and 2.6 wt.% Co, and taenite with 56 wt.% Ni and 0.15 wt.% Co formed by localized shock melting. A single impact probably melted the sub-mm sulfides, formed stishovite, and reheated and decomposed the martensite plates. Tishomingo and its near-twin Willow Grove, which has 28 wt.% Ni, differ from IAB-related irons like Santa Catharina and San Cristobal that contain 25-36 wt.% Ni, as they are highly depleted in moderately volatile siderophiles and enriched in Ir and other refractory elements. Tishomingo and Willow Grove therefore resemble IVB irons but are chemically distinct. The absence of cloudy taenite in these two irons shows that they cooled through 250 °C abnormally fast at >0.01 °C/yr. Thus this grouplet, like the IVA and IVB irons, suffered an early impact that disrupted their parent body when it was still hot. Our noble gas data show that Tishomingo was excavated from its parent body about 100 to 200 Myr ago and exposed to cosmic rays as a meteoroid with a radius of ∼50-85 cm.

Late Glacial and Holocene environmental history of the Pirin Mountains (SW Bulgaria): a paleolimnological study of Lake Dalgoto (2310 m)

Diatoms, Cladocera, and chironomids preserved in the sediments of Lake Dalgoto were studied to reconstruct the history of the lake ecosystem in the context of the vegetation history as represented by the pollen stratigraphy. Younger Dryas silty sediments at the base of the core are characterized by low diversity of aquatic organisms. The transition to the Holocene is indicated by a sharp change from silt to clay-gyttja. The migration and expansion of trees at lower elevations between 10200 and 8500 14C-yr BP, along with higher diversities and concentrations of aquatic organisms and the decreased proportion of north-alpine diatoms, point to rapidly rising summer temperatures. After 6500 14C-yr BP the expansion of Pinus mugo in the catchment coincides with signs of natural eutrophication as recorded by an increase of planktonic diatoms. In the late Holocene (4000–0 14C-yr BP) Pinus peuce and Abies are reduced and Picea expands. Cereal grains and disturbance indicators suggest late-Holocene human modification of the vegetation.

THE IMPACT OF FAMILY HISTORY ON MEDULLARY THYROID CANCER IN MEN2A PATIENTS

The American Thyroid Association recently classified all MEN2A-associated codons into increasing risk levels A-C and stated that some patients may delay prophylactic thyroidectomy if certain criteria are met. One criterion is a less aggressive family history of MTC but whether families with the same mutated codon have variable MTC aggressiveness is not well described. We developed several novel measures of MTC aggressiveness and compared families with the same mutated codon to determine if there is significant inter-familial variability. Pedigrees of families with MEN2A were reviewed for codon mutated and proportion of RET mutation carriers with MTC. Individuals with MTC were classified as having local or distant MTC and whether they had progressive MTC. MTC status and age were assessed at diagnosis and most advanced MTC stage. For those without MTC, age was recorded at prophylactic thyroidectomy or last follow-up if the patient did not have a thyroidectomy. For each pedigree, the mean age of members without MTC, with MTC, and the proportion of RET mutation carriers with local or distant and progressive MTC were calculated. We assessed differences in these variables using ANOVA and the Fisher’s exact test. Sufficient data for analysis were available for families with mutated codons 609 (92 patients from 13 families), 618 (41 patients from 7 families), and 634 (152 patients from 13 families). The only significant differences found were the mean age of patients without MTC between families with codon 609 and 618 mutations even after accounting for prophylactic thyroidectomy (p=0.006 and 0.001, respectively), and in the mean age of MTC diagnosis between families with codon 618 and 634 mutations even after accounting for symptomatic presentation (p=0.023 and 0.014, respectively). However, these differences may be explained by generational differences in ascertainment of RET carriers and the availability of genetic testing when the proband initially presented.

Jurassic sedimentation history at DSDP Hole 76-534A

Site 534 reflects a complex interplay of global, basinal, and local influences on sedimentation during the Callovian and Late Jurassic. Rifting and rapid subsidence of the continental margins of the North Atlantic-Tethys seaway occurred during the late Early Jurassic (Sinemurian-Pliensbachian), but rapid spreading between the North American margin (Blake Spur Ridge and magnetic lineation) and the northwest African margin did not commence until the Bathonian or earliest Callovian. Site 534, drilled on marine magnetic anomaly "M-28" of Bryan et al. (1980), was initially about 150 km from either continental margin. The ?middle Callovian basal sediments are dusky red silty marl. Callovian transgression led to active carbonate platforms on the margin, recorded at Site 534 as a rise in the CCD (carbonate compensation depth), then arrival of lime-rich turbidites from the Blake Plateau platform across the Blake Spur Ridge. The host pelagic sediment is greenish black, organic-rich, radiolarian-rich, silty claystone. Hydrothermal activity on the nearby spreading ridge enriched this lower unit in metals. In the Oxfordian, the input of terrestrial silt rapidly diminished; radiolarians or other bioclasts were not preserved. The dark variegated claystone has fine-grained marl and reddish claystone turbidite beds. The late Callovian-Oxfordian Western Tethys has radiolarian chert deposition, marine hiatuses, or organic-rich sediments. The Kimmeridgian and Tithonian had a stable or receding sea level. Near the end of the Jurassic many of the carbonate platforms of the margins were buried beneath prograding fan or alluvial deposits. Carbonate deposition shifted to the deep sea. Site 534 records the deepening of the CCD and ACD (aragonite compensation depth) during the Kimmeridgian and early Tithonian, then a rise of the ACD in the middle Tithonian. Similar trends occurred throughout the Western Tethys-Atlantic. High nannofossil productivity of the seaway led to deposition of very widespread white micritic limestone in the late Tithonian-Berriasian. The underlying sediment had a slower deposition rate of carbonate, therefore its higher clay and associated Fe content produced a red marl. A short sea-level incursion occurred on the Atlantic margins during the Kimmeridgian and is reflected in the Site 534 greenish gray marl unit by numerous turbidite beds of shallow-water carbonates.

The year book of daily recreation and information, concerning remarkable men and manners, times and seasons, solemnities and merrymakings, antiquities and novelties: on the plan of the Every=day book and Table book ... forming a complete history of the year; and a perpetual key to the almanac.

Printed in double columns.

Palaeoclimatic implications of the growth history and stable isotope (delta O-18 and delta C-13) geochemistry of a Middle to Late Pleistocene stalagmite from central-western Italy

The age structure and, stable isotope composition of a stalagmite (CC I) from an upland cave in central-western Italy were studied to investigate regional response to global climatic changes. Four growth phases are constrained by 28 thermal ionization and multi-collector inductively coupled plasma mass spectrometry Th-U ages and reveal intermittent deposition through the period between Marine isotope Stage (MIS) 11 and 3 (similar to380 and similar to43 kyr). Most of the growth took place between similar to380 and similar to280 kyr, a period punctuated briefly by a hiatus in deposition through the glacial maximum of MIS 10. Growth was terminated abruptly at 280 kyr just prior to the MIS 8 glacial maximum. With a present-day chamber temperature of 7.5 degreesC, the timing of hiatuses close to these glacial maxima point to freezing conditions at the time. No deposition was recorded through the entirety of MIS 7 and most of MIS 6, whilst two minor growth phases occurred at similar to141-125 and similar to43 kyr. Growth at 141 kyr indicates temperatures >0 degreesC at a time when MIS 6 ice volumes were close to their maximum. High stable carbon isotope (delta(13)C) values (similar to2.8parts per thousand to +3.1parts per thousand) throughout the stalagmite's growth reflect a persistently low input of biogenic CO2, indicating that the steep, barren and alpine-like recharge area of today ha's been in existence for at least the last similar to380 kyr. During MIS 9, the lowest delta(13)C values occur well after maximum interglacial conditions, suggesting a lag in the development of post-glacial soils in this high-altitude karst. The stable oxygen isotope (delta(18)O) trends match the main structural features of the major climate proxy records (SPECMAP, Vostok and Devils Hole), suggesting that the delta(18)O of CC1 has responded to global-scale climate changes, whilst remarkable similarity exists between CC1 delta(18)O and regional sea-surface temperature reconstructions from North Atlantic core ODP980 and southwest Pacific marine core MD97-2120 through the most detailed part of the CC1 record, MIS 9-8. The results suggest that CC1 and other stalagmites from the cave have the potential to capture a long record of regional temperature trends, particularly in regards to the relative severity of Pleistocene glacial stages. (C) 2004 Elsevier B.V. All rights reserved.

(U-Th)/He and 40Ar/39Ar Geochronology of Weathering, Hamersley Province, Australia: Implications for weathering history and landscape Evolution

(U–Th)/He dating of goethite, when combined with quantification of diffusive 4He loss by the 4He/3He methodology, provides reliable corrected ages for minerals precipitated in weathering profiles. We have combined (U–Th)/He dating of supergene goethite with 40Ar/39Ar dating of supergene manganese oxides to study the weathering history and landscape evolution in the Hamersley Province, northwestern Australia. Incremental heating 40Ar/39Ar analysis of 187 grains of Mn oxides from 65 samples (44 hand specimens) collected from weathering profiles at seven field sites across the Hamersley Province yield precipitation ages ranging from 63.4 ± 0.9 to 1.5 ± 0.2 Ma. These results, combined with previous results of 40Ar/39Ar dating of Mn oxides (Vasconcelos, 1998 Vasconcelos, P.V., 1998. Unpub. report, pp. 1–278.Vasconcelos, 1998 and Cochrane, 2003), reveal a protracted and episodic history of weathering and landscape evolution, which was already ongoing in Late Cretaceous and spans the Palaeogene and Neogene. Seventy-three grains of goethite from 39 samples extracted from 21 hand specimens, collected from the same field sites where the Mn oxides originated, were dated by the (U–Th)/He method. Internally consistent (U–Th)/He ages, which range from 84.3 ± 12.2 to 3.3 ± 0.5 Ma, have been obtained for most samples when corrections are applied for 10% helium diffusive loss. The geochronological results obtained show remarkable similarity in the distribution of ages associated with supergene mineral precipitation. The widespread occurrence of iron oxides such as goethite in soils and weathering profiles and the successful application of (U–Th)/He dating of goethite offers great opportunities for extracting the wealth of palaeoclimatic and palaeoenvironmental information recorded by these profiles on the surface of terrestrial planets such as Earth and Mars.

Select toxic metals status of pregnant women with history of pregnancy complications in Benin City, South-South Nigeria.

Toxic metals are part of the most important groups of environmental pollutants that can bind to vital cellular components and interfere with their functions via inhalation, foods, water etc. The serum levels of toxic metals (lead, mercury, cadmium and arsenic) in pregnant women with history of pregnancy complications, pregnant women without history of pregnancy complication and non-pregnant women in Benin City, South – South Nigeria was investigated in this paper, with total of 135 healthy women comprising of 45 pregnant women with history of previous pregnancy complications, 45 pregnant women without history of pregnancy complications and 45 non-pregnant women without history of pregnancy complications (controls). Some demographic characteristics and 4ml of blood samples were obtained from each subject for the analysis of lead, mercury, cadmium and arsenic by standard methods. Pregnant women with history of pregnancy complications recorded a highly significant increase in the toxic metal (lead) mean value of 25.81μg/dl as against 23.70μg/dl for pregnant women without history of pregnancy complications and 11.23μg/dl for non-pregnant (control) women without history of pregnancy complications as well as significant increases in the mean values of other toxic metals (mercury, cadmium and arsenic) compared with controls (p<0.001). The selected toxic metals (Pb, Hg, Cd and As) may be involved in the development of pregnancy complications among pregnant women in Benin City, South– South Nigeria. Lead in particular may pose threat to mothers and fetuses as its mean values in the two groups of pregnant women were well above normal.

[how The Gynecologist Can Guide Women With A Family History Of Cancer?].

36

Ginastica de Grande Area : uma realidade possivel no contexto escolar

Universidade Estadual de Campinas. Faculdade de Educação Física

Recalled and recorded bowel habits confirm early onset and high frequency of constipation in day-care nursery children

CONTEXT: Mothers recall early-onset constipation in children attending gastroenterology clinics. OBJECTIVES: To study the bowel habit of young children in the community to determine, first, whether early-onset constipation is confirmed in this setting and, second, the agreement between recalled and recorded bowel habit. METHODS:Defecation data of 57 children aged 6.0-40.7 mo were obtained by maternal recall (questionnaire on predominant stool characteristics) and by record (1,934 defecations registered prospectively at home and in the nursery). The bowel habit was classified according to stool frequency and proportion of stool characteristics (soft, hard and/or runny). Two criteria were used to classify recorded data, since the cutoff point for hard stools to identify constipation is undefined in children: predominant criterion and adult criterion, respectively with >50% and >25% of stools with altered consistency. Bowel habit categories were: adequate, constipation, functional diarrhea and "other bowel habit". Nonparametric statistics, and the Kappa index for agreement between recalled and recorded bowel habit, were used. RESULTS: Constipation occurred in 17.5%, 10.5%, 19.3% of the children by recall, the predominant and the adult criteria, respectively. Constipation was the main recalled alteration, vs 12.3% "other bowel habit". Only one child classified as having functional diarrhea (by the adult criterion). Agreement between recalled and recorded bowel habit was fair for constipation, by the predominant and the adult criteria (K = 0.28 and 0.24, respectively), but only slight (K <0.16) for other bowel habit categories. Individual data, however, pointed to a better relationship between recalled constipation and the adult rather than the predominant criterion. CONCLUSIONS: Frequent early-onset constipation was confirmed. Fair agreement between recalled and recorded constipation by the two used criteria indicates that recalled data are quite reliable to detect constipation.

Natural history and population data of fishes in caves of the Serra do Ramalho karst area, Middle São Francisco basin, northeastern Brazil

During the exploration and mapping of new caves in Serra do Ramalho karst area, southern Bahia state, cavers from the Grupo Bambuí de Pesquisas Espeleológicas - GBPE (Belo Horizonte) noticed the presence of troglomorphic catfishes (species with reduced eyes and/or melanic pigmentation), which we intensively investigated with regards to their ecology and behavior since 2005. Non-troglomorphic fishes regularly found in the studied caves were included in this investigation. We present here data on the natural history of two troglobitic (exclusively subterranean troglomorphic species) fishes - Rhamdia enfurnada Bichuette & Trajano, 2005 (Heptapteridae; Gruna do Enfurnado) and Trichomycterus undescribed species (Trichomycteridae; Lapa dos Peixes and Gruna da Água Clara), and non-troglomorphic Hoplias cf. malabaricus, probably a troglophile (able to form populations both in epigean and subterranean habitats) in the Gruna do Enfurnado, and Pimelodella sp., a species with a sink population in the Lapa dos Peixes.

Ecology and natural history of Akodon lindberghi (Rodentia, Sigmodontinae) in southeastern Brazil

We studied the ecology and natural history of the globally threatened and poorly known Akodon lindberghi Hershkovitz, 1990 in Parque Nacional da Serra da Canastra (PNSC) and Juiz de Fora (JF), southeastern Brazil. From November 1998 to September 2001 a total of 131 individuals were captured in wire-cage live-traps and 52 by pitfalls traps. They were all marked and released at the site. The largest abundances were registered during the dry season, and most of the captures occurred in open habitats. The mean body mass of the two populations was significantly different (18.1 g at PNSC versus 13.1 g at JF; H = 46.2678, g.l.=2, p<0.001). In PNSC, individuals were reproductively active from August to February, and juveniles were present from May to August. The results suggest that the changes in vegetation structure caused by deforestation and intensive agricultural activities could increase the predation rate, affecting the mean body mass of the population.

Larva of Atractocerus Brasiliensis (Lepeletier & Audinet-Serville, 1825) (Lymexylidae, Atractocerinae)

The larva of Atractocerus brasiliensis (Lepeletier & Audinet-Serville, 1825), collected for the first time in Pinus oocarpa Schiede ex Schltdl. (Pinaceae) is described and illustrated. Until now, for Lymexylidae, only the larva of Melittomma sp. (Melittomminae) was known from the neotropical region (Brazil). Biological notes, a comparison with the description of A. brevicornis, the type-species of the genus (recorded from Africa and Madagascar), and history of the known lymexylid larvae are also included.