Early human impacts and ecosystem reorganization in southern-central Africa.

Modern Homo sapiens engage in substantial ecosystem modification, but it is difficult to detect the origins or early consequences of these behaviors. Archaeological, geochronological, geomorphological, and paleoenvironmental data from northern Malawi document a changing relationship between forager presence, ecosystem organization, and alluvial fan formation in the Late Pleistocene. Dense concentrations of Middle Stone Age artifacts and alluvial fan systems formed after ca. 92 thousand years ago, within a paleoecological context with no analog in the preceding half-million-year record. Archaeological data and principal coordinates analysis indicate that early anthropogenic fire relaxed seasonal constraints on ignitions, influencing vegetation composition and erosion. This operated in tandem with climate-driven changes in precipitation to culminate in an ecological transition to an early, pre-agricultural anthropogenic landscape.

High-resolution surface faulting from the 1983 Idaho Lost River Fault Mw 6.9 earthquake and previous events.

We present high-resolution mapping and surface faulting measurements along the Lost River fault (Idaho-USA), a normal fault activated in the 1983 (Mw 6.9) earthquake. The earthquake ruptured ~35 km of the fault with a maximum throw of ~3 m. From new 5 to 30 cm-pixel resolution topography collected by an Unmanned Aerial Vehicle, we produce the most comprehensive dataset of systematically measured vertical separations from ~37 km of fault length activated by the 1983 and prehistoric earthquakes. We provide Digital Elevation Models, orthophotographs, and three tables of: (i) 757 surface rupture traces, (ii) 1295 serial topographic profiles spaced 25 m apart that indicate rupture zone width and (iii) 2053 vertical separation measurements, each with additional textual and numerical fields. Our novel dataset supports advancing scientific knowledge about this fault system, refining scaling laws of intra-continental faults, comparing to other earthquakes to better understand faulting processes, and contributing to global probabilistic hazard approaches. Our methodology can be applied to other fault zones with high-resolution topographic data.

Combined heart-lung transplantation from a donation after circulatory death donor.

Combined heart-lung transplantation is the optimal treatment option for many patients with end-stage heart failure and fixed severe pulmonary hypertension. It offers the only possibility of long-term survival and a return to a normal quality of life. Unfortunately, it is rarely performed because of donor organ allocation policies. We present the case of a critically ill 24-year-old man, who after waiting for >100 days in-hospital on the urgent transplant list, deteriorated further and underwent the first successful heart-lung transplant with organs from a donation after circulatory death.

Earliest known Oldowan artifacts at >2.58 Ma from Ledi-Geraru, Ethiopia, highlight early technological diversity.

The manufacture of flaked stone artifacts represents a major milestone in the technology of the human lineage. Although the earliest production of primitive stone tools, predating the genus Homo and emphasizing percussive activities, has been reported at 3.3 million years ago (Ma) from Lomekwi, Kenya, the systematic production of sharp-edged stone tools is unknown before the 2.58-2.55 Ma Oldowan assemblages from Gona, Ethiopia. The organized production of Oldowan stone artifacts is part of a suite of characteristics that is often associated with the adaptive grade shift linked to the genus Homo Recent discoveries from Ledi-Geraru (LG), Ethiopia, place the first occurrence of Homo ∼250 thousand years earlier than the Oldowan at Gona. Here, we describe a substantial assemblage of systematically flaked stone tools excavated in situ from a stratigraphically constrained context [Bokol Dora 1, (BD 1) hereafter] at LG bracketed between 2.61 and 2.58 Ma. Although perhaps more primitive in some respects, quantitative analysis suggests the BD 1 assemblage fits more closely with the variability previously described for the Oldowan than with the earlier Lomekwian or with stone tools produced by modern nonhuman primates. These differences suggest that hominin technology is distinctly different from generalized tool use that may be a shared feature of much of the primate lineage. The BD 1 assemblage, near the origin of our genus, provides a link between behavioral adaptations-in the form of flaked stone artifacts-and the biological evolution of our ancestors.

PALEOANTHROPOLOGY. Response to Comment on "Early Homo at 2.8 Ma from Ledi-Geraru, Afar, Ethiopia".

Hawks et al. argue that our analysis of Australopithecus sediba mandibles is flawed and that specimen LD 350-1 cannot be distinguished from this, or any other, Australopithecus species. Our reexamination of the evidence confirms that LD 350-1 falls outside of the pattern that A. sediba shares with Australopithecus and thus is reasonably assigned to the genus Homo.

Paleoanthropology. Early Homo at 2.8 Ma from Ledi-Geraru, Afar, Ethiopia.

Our understanding of the origin of the genus Homo has been hampered by a limited fossil record in eastern Africa between 2.0 and 3.0 million years ago (Ma). Here we report the discovery of a partial hominin mandible with teeth from the Ledi-Geraru research area, Afar Regional State, Ethiopia, that establishes the presence of Homo at 2.80 to 2.75 Ma. This specimen combines primitive traits seen in early Australopithecus with derived morphology observed in later Homo, confirming that dentognathic departures from the australopith pattern occurred early in the Homo lineage. The Ledi-Geraru discovery has implications for hypotheses about the timing and place of origin of the genus Homo.

Paleoanthropology. Late Pliocene fossiliferous sedimentary record and the environmental context of early Homo from Afar, Ethiopia.

Sedimentary basins in eastern Africa preserve a record of continental rifting and contain important fossil assemblages for interpreting hominin evolution. However, the record of hominin evolution between 3 and 2.5 million years ago (Ma) is poorly documented in surface outcrops, particularly in Afar, Ethiopia. Here we present the discovery of a 2.84- to 2.58-million-year-old fossil and hominin-bearing sediments in the Ledi-Geraru research area of Afar, Ethiopia, that have produced the earliest record of the genus Homo. Vertebrate fossils record a faunal turnover indicative of more open and probably arid habitats than those reconstructed earlier in this region, which is in broad agreement with hypotheses addressing the role of environmental forcing in hominin evolution at this time. Geological analyses constrain depositional and structural models of Afar and date the LD 350-1 Homo mandible to 2.80 to 2.75 Ma.

Near-field deformation from the El Mayor-Cucapah earthquake revealed by differential LIDAR.

Large [moment magnitude (M(w)) ≥ 7] continental earthquakes often generate complex, multifault ruptures linked by enigmatic zones of distributed deformation. Here, we report the collection and results of a high-resolution (≥nine returns per square meter) airborne light detection and ranging (LIDAR) topographic survey of the 2010 M(w) 7.2 El Mayor-Cucapah earthquake that produced a 120-kilometer-long multifault rupture through northernmost Baja California, Mexico. This differential LIDAR survey completely captures an earthquake surface rupture in a sparsely vegetated region with pre-earthquake lower-resolution (5-meter-pixel) LIDAR data. The postevent survey reveals numerous surface ruptures, including previously undocumented blind faults within thick sediments of the Colorado River delta. Differential elevation changes show distributed, kilometer-scale bending strains as large as ~10(3) microstrains in response to slip along discontinuous faults cutting crystalline bedrock of the Sierra Cucapah.

Slip in the 1857 and earlier large earthquakes along the Carrizo Plain, San Andreas Fault.

The moment magnitude (Mw) 7.9 Fort Tejon earthquake of 1857, with a approximately 350-kilometer-long surface rupture, was the most recent major earthquake along the south-central San Andreas Fault, California. Based on previous measurements of its surface slip distribution, rupture along the approximately 60-kilometer-long Carrizo segment was thought to control the recurrence of 1857-like earthquakes. New high-resolution topographic data show that the average slip along the Carrizo segment during the 1857 event was 5.3 +/- 1.4 meters, eliminating the core assumption for a linkage between Carrizo segment rupture and recurrence of major earthquakes along the south-central San Andreas Fault. Earthquake slip along the Carrizo segment may recur in earthquake clusters with cumulative slip of approximately 5 meters.

Climate-modulated channel incision and rupture history of the San Andreas Fault in the Carrizo Plain.

The spatial and temporal distribution of fault slip is a critical parameter in earthquake source models. Previous geomorphic and geologic studies of channel offset along the Carrizo section of the south central San Andreas Fault assumed that channels form more frequently than earthquakes occur and suggested that repeated large-slip earthquakes similar to the 1857 Fort Tejon earthquake illustrate typical fault behavior. We found that offset channels in the Carrizo Plain incised less frequently than they were offset by earthquakes. Channels have been offset by successive earthquakes with variable slip since ~1400. This nonuniform slip history reveals a more complex rupture history than previously assumed for the structurally simplest section of the San Andreas Fault.

The impact of intra-operative transoesophageal echocardiography on cardiac surgical practice.

The use of transoesophageal echocardiography during cardiac surgery has increased dramatically and it is now widely accepted as a routine monitoring and diagnostic tool. A prospective study was carried out between September 2004 and September 2007, and included all patients in whom intra-operative echocardiography was performed, 2 473 (44%) out of a total of 5 591 cases. Changes to surgery were subdivided into predictable (where echocardiographic examination was planned specifically to guide surgery) and unpredictable (new pathology not diagnosed pre-operatively). A change in the planned surgical procedure was documented in 312 (15%) cases. In 216 (69%) patients the changes were predictable and in 96 (31%) they were unpredictable. The number of predictable changes increased between 2004-5 and 2006-7 (8% vs 13%, p = 0.025). In these cases, intra-operative echocardiography was specifically requested by the surgeon to help determine the operative intervention. This has implications for consent and operative risk, which have yet to be fully determined.

The Papworth BiVent tube: a new device for lung isolation.

Provision of one lung ventilation can be technically challenging, particularly for anaesthetists who are only occasionally required to isolate one lung from the other. A new double lumen endotracheal tube, the Papworth BiVent Tube, has been designed to enable rapid and reliable lung isolation using any bronchus blocker without the need for fibreoptic endoscopic guidance. In this study, an airway-training manikin was used to assess ease of tracheal intubation and lung isolation using the Papworth BiVent tube. Ease of intubation was compared to a single lumen endotracheal tube and a conventional double lumen endobronchial tube. Ease of lung isolation when using a bronchus blocker was compared to a single lumen tube combined with a bronchial blocker. Tracheal intubation using the Papworth BiVent tube was found to be easier than when using a conventional double lumen endobronchial tube. Lung isolation using the Papworth BiVent tube used in combination with a bronchus blocker was achieved more reliably and rapidly than when using a single lumen tube and bronchus blocker.

The Papworth BiVent tube: a feasibility study of a novel double-lumen endotracheal tube and bronchial blocker in human cadavers.

BACKGROUND: A novel double-lumen endotracheal tube, the Papworth BiVent tube, has been designed to allow the rapid passage of a blocker into either main bronchus, without fibreoptic endoscopic guidance. METHODS: The feasibility of lung isolation and one-lung ventilation (OLV) in human cadavers is examined, along with displacement of the bronchus blocker during head and neck movement. RESULTS: Cadaveric endotracheal intubation with the Papworth BiVent tube was straightforward and comparable with intubation with a conventional single-lumen tube (SLT). Reliable lung isolation was achieved considerably faster using the Papworth BiVent tube than with a bronchoscopically guided bronchial blocker through an SLT (mean 7.75 s BiVent tube vs 128.2 s SLT). The Papworth BiVent tube also prevented displacement of the blocker from its position in the bronchus on head movement. CONCLUSIONS: This study in human cadavers has shown that it is feasible to use the Papworth BiVent tube to attain rapid and secure lung isolation for OLV. Further work is required in clinical settings.

Cardiopulmonary bypass and deep hypothermic circulatory arrest in a massively obese patient.

As a consequence of the rising global prevalence and magnitude of obesity, a greater proportion of patients presenting for cardiac surgery is morbidly obese. Being overweight (body mass index; BMI 25-29.9 kg/m(2)) or obese (BMI 30-35 kg/m(2)) appears to confer some survival benefit following cardiac surgery. By contrast, morbid obesity (BMI >40 kg/m(2)) is associated with an increased likelihood of postoperative complications and prolonged intensive care unit and hospital length of stay. The physical difficulties encountered when managing this group of patients is exemplified by those undergoing complex, multiple procedures requiring prolonged cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA). We present the successful management of a massively obese 19-year-old male (BMI 45 kg/m(2)) with Marfan's syndrome who required aortic root and arch replacement under DHCA. The selection of extracorporeal circuit components to accommodate a large circulating volume and permit high CPB flow rates (>9 l/min) is discussed.

Local clinical quality monitoring for detection of excess operative deaths.

A monitoring system for cardiac surgery has been in use at Papworth Hospital for 10 years. We wished to determine whether this system would have detected an increase in deaths associated with a single practitioner, whether a poorly performing doctor or a serial killer such as Dr Harold Shipman, whose activities went undetected in the absence of a monitoring system for nearly a quarter of a century. Random extra deaths were artificially introduced into the practice of a surgeon and an anaesthetist in a way that broadly reproduced Shipman's pattern. The standard monitoring system was then used to analyse the hypothetical data thus generated. Using the current standard monitoring, the excess deaths would have been detected in less than 10 months. Suspicions would have been raised even earlier. Robust local quality monitoring of risk-adjusted outcomes is possible and, in our opinion, essential.