Oldowan sites in primary geological context are rare in the archaeological record. Here we describe the depositional environment of Oldowan occurrences at Kanjera South, Kenya, based on field ...descriptions and granulometric analysis. Excavations have recovered a large Oldowan artefact sample as well as the oldest substantial sample of archaeological fauna. The deposits at Kanjera South consist of 30 m of fluvial, colluvial and lacustrine sediments. Magneto- and biostratigraphy indicate the Kanjera South Member of the Kanjera Formation was deposited during 2.3–1.92 Ma, with 2.0 Ma being a likely age for the archaeological occurrences. Oldowan artefacts and associated fauna were deposited in the colluvial and alluvial silts and sands of beds KS1–3, in the margins of a lake basin. Field descriptions and granulometric analysis of the sediment fine fraction indicate that sediments from within the main archaeological horizon were emplaced as a combination of tractional and hyperconcentrated flows with limited evidence of debris-flow deposition. This style of deposition is unlikely to significantly erode or disturb the underlying surface, and therefore promotes preservation of surface archaeological accumulations. Hominins were repeatedly attracted to the site locale, and rapid sedimentation, minimal bone weathering and an absence of bone or artefact rounding further indicate that fossils and artefacts were quickly buried.
Deep brain stimulation (DBS) of the posterior hypothalamus was found to be effective in the treatment of drug-resistant chronic cluster headache. We report the results of a multicentre case series of ...six patients with chronic cluster headache in whom a DBS in the posterior hypothalamus was performed. Electrodes were implanted stereotactically in the ipsilateral posterior hypothalamus according to published coordinates 2 mm lateral, 3 mm posterior and 5 mm inferior referenced to the mid-AC-PC line. Microelectrode recordings at the target revealed single unit activity with a mean discharge rate of 17 Hz (range 13-35 Hz, n = 4). Out of six patients, four showed a profound decrease of their attack frequency and pain intensity on the visual analogue scale during the first 6 months. Of these, one patient was attack free for 6 months under neurostimulation before returning to the baseline which led to abortion of the DBS. Two patients had experienced only a marginal, non-significant decrease within the first weeks under neurostimulation before returning to their former attack frequency. After a mean follow-up of 17 months, three patients are almost completely attack free, whereas three patients can be considered as treatment failures. The stimulation was well tolerated and stimulation-related side-effects were not observed on long term. DBS of the posterior inferior hypothalamus is an effective therapeutic option in a subset of patients. Future controlled multi-centre trials will need to confirm this open-label experience and should help to better define predictive factors for non-responders.
Forest soils have a large capacity of stocking and cycling carbon, incorporated by organic matter and evaded by roots and soil microbiota as CO₂. Soil respiration can indicate ecosystem processes, ...but little is known about the successional, seasonal and diurnal variation in CO₂ flux. This study presents estimations of soil CO₂ efflux in a seasonal Atlantic forest fragment (FF) and an adjacent 15 years-old restoration site (RS), in two seasons (winter-dry and summer-rainy), during 24-hour periods, in southern Brazil. Measurements were performed with an infrared gas analyser at 2-hour intervals. Respiration rates were 50% higher in the rainy season, both in FF (261, against 135 mg m⁻² s⁻¹ in the dry season) and RS (237 and 127 mg m⁻² s⁻¹), indicating that higher humidity and temperature promoted higher soil biota activity. The soil respiration was higher at FF only in the dry season, revealing that this environment may be less sensitive to water limitation. Greater overnight respiration was observed in the dry season for both sites, likely reflecting more intense microbial metabolism at night in this season. There was no rainy season diurnal variation. Seasonal and daily variation suggests that soil respiration in the RS is more sensitive to warmer and dryer conditions.
Data from a dense urban meteorological network (UMN) are analyzed, revealing the spatial heterogeneity and temporal variability of the Twin Cities (Minneapolis–St. Paul, Minnesota) canopy-layer urban ...heat island (UHI). Data from individual sensors represent surface air temperature (SAT) across a variety of local climate zones within a 5000-km² area and span the 3-yr period from 1 August 2011 to 1 August 2014. Irregularly spaced data are interpolated to a uniform 1 km × 1 km grid using two statistical methods: 1) kriging and 2) cokriging with impervious surface area data. The cokriged SAT field exhibits lower bias and lower RMSE than does the kriged SAT field when evaluated against an independent set of observations. Maps, time series, and statistics that are based on the cokriged field are presented to describe the spatial structure and magnitude of the Twin Cities metropolitan area (TCMA) UHI on hourly, daily, and seasonal time scales. The average diurnal variation of the TCMA UHI exhibits distinct seasonal modulation wherein the daily maximum occurs by night during summer and by day during winter. Daily variations in the UHI magnitude are linked to changes in weather patterns. Seasonal variations in the UHI magnitude are discussed in terms of land–atmosphere interactions. To the extent that they more fully resolve the spatial structure of the UHI, dense UMNs are advantageous relative to limited collections of existing urban meteorological observations. Dense UMNs are thus capable of providing valuable information for UHI monitoring and for implementing and evaluating UHI mitigation efforts.
In social stratification research, the most frequently used social class schema are based on employment relations (EGP and ESEC). These schemes have been propelled to paradigms for research on social ...mobility and educational inequalities and applied in cross-national research for both genders. Using the European Working Conditions Survey, we examine their criterion and construct validity across 31 countries and for both genders. We investigate whether classes are welldelineated by the theoretically assumed dimensions of employment relations and we assess how several measures of occupational advantage differ across classes. We find broad similarity in the criterion validity of EGP and ESEC across genders and countries as well as satisfactory levels of construct validity. However, the salariat classes are too heterogeneous and their boundaries with the intermediate classes are blurred. To improve the measurement of social class, we propose to differentiate managerial and professional occupations within the lower and higher salariat respectively. We show that implementing these distinctions in ESEC and EGP improves their criterion validity and allows to better identify privileged positions.
Abstract Wernicke’s encephalopathy (WE) is a severe brain disorder, first described in 1881, and is caused by a nutritional deficiency of thiamine (vitamin B1) found mostly in patients suffering from ...chronic alcoholism. In addition, WE can also complicate bariatric surgery if adequate vitamin supplementation is not insured. Without immediate treatment, the prognosis is poor and the mortality rate is high. Most patients present with atypical neurological symptoms, which hampers rapid diagnosis. We present a 40-year-old woman who underwent gastroplasty combined with gastric banding for severe obesity. She experienced repetitive vomiting and her diet was without vitamin supplementation. After three months she developed convergent strabismus, apathy and urinary incontinence, which was diagnosed as WE and treated as such. Six months later her recovery was incomplete, still showing gait difficulties and nystagmus. We aim to show that adequate vitamin supplementation in patients undergoing gastroplasty is necessary, especially considering the risk of permanent neurological deficits.
Vultures comprise two geographically isolated and taxonomically distinct groups, Old World accipitrids and New World vulturids, and provide a classic case of convergent evolution. In both regions, ...several species of vultures often feed together in large numbers on carcasses. Behavioral studies of East African and Amazonian vultures have documented parallels in apparent ecological separation within this guild of specialized scavengers. Here morphological differences in skull, beak, and manibular dimensions are compared among sympatric vultures in East Africa, South Africa, the Indian subcontinent, Amazonia, and the Pleistocene Rancho La Brea deposits in California. A discriminant function analysis based on morphological indices separates three basic feeding types: rippers, gulpers, and scrappers. Vultures of the three feeding types are present in both Pleistocene and Recent assemblages and show a similar distribution of body sizes into three size classes, suggesting that competition has favored similar pathways of ecological separation. This is true even when phylogenetic differences among some of the assemblages are partially accounted for. Comparisons between the fossil and extant New World vultures indicate that more specialized species were prone to extinction and that there has been a reduction in body size since the Pleistocene.
The number of oocytes recovered from Bos taurus indicus females subjected to ovum pick-up averaged two to four times greater compared to Bos taurus taurus females. The objective of the present study ...was to test the hypothesis that this difference in oocyte yield was due to more preantral follicles in the ovaries of Bos indicus females. Ovaries (n = 64) from Nelore (Bos indicus) fetuses (n = 10), heifers (n = 12), and cows (n = 10), and Aberdeen Angus (Bos taurus) fetuses (n = 10), heifers (n = 12), and cows (n = 10) were cut longitudinally into halves, fixed, and processed for histological evaluation. The number of preantral follicles was estimated by counting them in each histological section, using the oocyte nucleus as a marker and employing a correction factor. The average number of preantral follicles in the ovaries of Bos indicus vs Bos taurus was (mean ± SD) 143,929 ± 64,028 vs 285,155 ± 325,195 for fetuses, 76,851 ± 78,605 vs 109,673 ± 86,078 for heifers, and 39,438 ± 31,017 vs 89,577 ± 86,315 for cows (P > 0.05). The number of preantral follicles varied greatly among individual animals within the same category, as well as between breeds. In conclusion, we inferred that the higher oocyte yield from Bos indicus females was not due to a greater ovarian reserve of preantral follicles. Therefore, mechanisms controlling follicle development after the preantral stage likely accounted for differences between Bos indicus and Bos taurus females in number of oocytes retrieved at ovum pick-up.
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