A multiscale stratigraphic investigation of the context of StW 573 'Little Foot' and Member 2, Sterkfontein Caves, South Africa.

The Sterkfontein Caves is currently the world's richest Australopithecus-bearing site. Included in Sterkfontein's hominin assemblage is StW 573 ('Little Foot'), a near-complete Australopithecus skeleton discovered in Member 2 in the Silberberg Grotto. Because of its importance to the fossil hominin record, the geological age of StW 573 has been the subject of significant debate. Three main hypotheses have been proposed regarding the formation and age of Member 2 and by association StW 573. The first proposes that Member 2 (as originally defined in the type section in the Silberberg Grotto) started to accumulate at around 2.58 Ma and that the unit is contained within the Silberberg Grotto. The second proposes that Member 2 started forming before 3.67 ± 0.16 Ma and that the deposit extends into the Milner Hall and close to the base of the cave system. The third proposes a 'two-stage burial scenario', in which some sediments and StW 573 represent a secondary and mixed-age accumulation reworked from a higher cave. The stratigraphic and sedimentological implications of these hypotheses are tested here through the application of a multiscale investigation of Member 2, with reference to the taphonomy of the StW 573 skeleton. The complete infilling sequence of Member 2 is described across all exposures of the deposit in the Silberberg Grotto and into the Milner Hall. Sediments are generally stratified and conformably deposited in a sequence of silty sands eroded from well-developed lateritic soils on the landscape surface. Voids, clasts and bioclasts are organized consistently across and through Member 2 conforming with the underlying deposit geometry, indicating gradual deposit accretion with no distinct collapse facies evident and only localized intra-unit postdepositional modification. The stratigraphy and sedimentology of Member 2 support a simple single-stage accumulation process of Member 2 and a primary association between the sediments of Member 2 and the StW 573 'Little Foot' skeleton.

Ultrasound-guided versus landmark approach for peripheral intravenous access by critical care nurses: a randomised controlled study.

OBJECTIVE: Establishing a peripheral intravenous catheter (PIVC) after a long intensive care unit (ICU) stay can be a challenge for nurses, as these patients may present vascular access issues. The aim of this study was to compare an ultrasound-guided method (UGM) versus the landmark method (LM) for the placement of a PIVC in ICU patients who no longer require a central intravenous catheter (CIVC). DESIGN: Randomised, controlled, prospective, open-label, single-centre study. SETTING: Tertiary teaching hospital. PARTICIPANTS: 114 awake patients hospitalised in ICU fulfilling the following criteria: (1) with a central venous catheter that was no longer required, (2) needing a PIVC to replace the central venous catheter and (3) with no apparent or palpable veins on upper limbs after tourniquet placement. INTERVENTION: Placement of a PIVC using an UGM. PRIMARY OUTCOME: Number of attempts for the establishment of a PIVC in the upper limbs. RESULTS: 57 patients were respectively included in both the UGM group and LM group. Stasis oedema in the upper limbs was the main cause of poor venous access identified in 80% of patients. Both the number of attempts (2 (1-4), p=0.911) and catheter lifespan ((3 (1-3) days and 3 (2-3) days, p=0.719) were similar between the two groups. Catheters in the UGM group tended to be larger (p=0.059) and be associated with increased extravasation (p=0.094). CONCLUSION: In ICU patients who no longer require a CIVC, use of an UGM for the establishment of a PIVC is not associated with a reduction in the number of attempts compared with LM. TRIAL REGISTRATION NUMBER: NCT02285712; Results.

RETRACTED: The revised stratigraphy of the hominin-bearing site of Kromdraai (Gauteng, South Africa) and associated perspectives.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the co-Editors-in-Chief and the authors. The Results and Discussion of this article duplicate significant parts of book chapter "A revised stratigraphy of Kromdraai", published by L.B., R.M., R.C., F.T. and J.B. in Braga, J. and Thackeray, J.F. (Eds.), "Kromdraai. A Birthplace of Paranthropus in the Cradle of Humankind" (2016, SUN MeDIA MeTRO, pp. 31-47), https://doi.org/10.18820/9781928355076. One of the conditions of submission of a paper to Journal of Human Evolution is that authors declare explicitly that that their work is original and has not been published previously. Reuse of any data should be appropriately cited. As such this article represents an abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.

Stratigraphic analysis of the Sterkfontein StW 573 Australopithecus skeleton and implications for its age.

StW 573, Little Foot, is the most complete Australopithecus skeleton yet discovered, with many of its bones found in their correct anatomical position. Since the discovery of the in situ skeleton in the Silberberg Grotto in 1997, several teams have attempted to date the fossil. This appeared a simple process because several flowstones are inter-bedded in the breccia above and below StW 573. Dating of these flowstones, using U-Pb (uranium-lead) isotope decay techniques, gave younger results than expected from the fauna and stratigraphic position, around 2.2 Ma (millions of years). Our recent stratigraphic, micromorphological and geochemical studies revealed that the stratigraphy is much more complicated than was previously thought, with localized post-depositional processes leading to the creation of voids within the breccia around the skeleton. These voids were then filled by multiple generations of flowstone growth. The research we present here demonstrates that the proposed dates based on the flowstone deposition can give only a minimum age for StW 573 and that the flowstone formation came after, and probably long after, the breccia deposition. If one takes account of the long evolution of these karst fillings, StW 573 appears to be significantly older than 2.2 Ma.

Intoxicación subclínica por monóxido de carbono en nuestra área sanitaria / Subclinical carbon monoxide poisoning in our health area

Presentamos un estudio observacional sobre la relación entre niveles elevados de carboxihemoglobina (COHB) e intoxicación subclínica por monóxido de carbono (CO) en nuestra área sanitaria, realizado en febrero y marzo de 2000, en 228 pacientes de ambos sexos, mayores de 18 años, que acudieron a Urgencias por diversos motivos. Previo consentimiento informado, obtuvimos una muestra de sangre venosa para determinar COHB y recogimos datos antropométricos, consumo de tabaco y tipo de calefacción domiciliaria. Los valores límite de COHB obtenidos fueron: en no fumadores, 1,9 por ciento; en fumadores de 1-10 cigarrillos/día, 5,1 por ciento; de 11-20, 6,9 por ciento y de > 20, 9,6 por ciento. El 25 por ciento de los pacientes presentaban una COHB elevada independientemente del hábito tabáquico, siendo el brasero de cisco la fuente de exposición más frecuente a CO (AU)

[Subclinical carbon monoxide poisoning in our health area]. / Intoxicación subclínica por monóxido de carbono en nuestra área sanitaria.

We present an observation study on the relatioship between high levels of carboxyhemoglobin (COHB) and subclinical poisoning by carbon monoxide (CO) in our health area. The study was carried out in February and March 2000 in 228 over 18-year-old patients of both sexes who went to the Emergency Room for various reasons. After an informed consent was conceded, a venous blood sample was obtained in order to determine the level of COHB; later, we collected the anthropometric data, the data relative to the tobacco use, and the data of the type of heating at home. The values limit of the COHB obtained were the following: in non smokers, 1.9%; in 1-10 cigarettes/day smokers, 5.2%; in 11-20 cigarettes/day smokers, 6.9%; in >20 cigarettes/day smokers, 9.6%. A COHB high level was observed in 25% of the patients regardless of the smoking habits, being the coal-dust slack brazier the source of most frequent exposure to CO.

[Primary pulmonary nodular amyloidosis]. / Amiloidosis nodular primaria pulmonar.

Localized nodular pulmonary amyloidosis is a very rare condition. We report the case of a man with an upper left lobe mass measuring 8 cm and a nodule measuring 3 cm at the same site. Both were detected by chance in radiologic images. Neoplasia was suspected and diagnosis was made by thoracotomy and lung biopsy. After two years of follow-up, the patient remains asymptomatic and the radiologic images are stable, with no clinical or analytical evidence of systemic amyloidosis or dysproteinemia.