New ages from Sehonghong rock shelter: Implications for the late Pleistocene occupation of highland Lesotho

Sehonghong rock shelter is situated in the eastern Lesotho highlands, a climatically extreme region of southern Africa. The site is one of a handful in southern Africa that preserves human occupations before, during, and after the Last GlacialMaximum(LGM). The site's long and well-preserved sequence makes it relevant to addressing questions of human mobility, subsistence, and technology in relation to broader environmental change. Here we present a Bayesian-modelled radiocarbon chronology for the LGM and terminal Pleistocene occupations at Sehonghong. Our model incorporates previously published radiocarbon dates and new accelerator mass spectrometry ages. We also present archaeological evidence to test the hypothesis that Sehonghong was occupied in a series of punctuated events, and that some of these occupations were more intensive than others. Previous chronological and archaeological data were insufficient for testing these hypotheses. The new dates and archaeological data confirmthat the sitewas occupied intensively in the early LGMand immediately thereafter. The site was otherwise occupied sporadically.We find that greater site occupation density is not always correlated with intensified use of local resources as measured by increased bipolar reduction and fish consumption. The new dates further confirm that Sehonghong contains some of the oldest evidence for systematic freshwater fishing in southern Africa. The availability of fish, a high fat protein source, probably stimulated human occupation, however sporadic, of suchmontane environments during cooler and drier periods. These findings suggest behavioural variability in response to shifting mobility and subsistence strategies. Our brief discussion informs upon huntergatherer occupation of southern Africanmontane environments more broadly and human behavioural variability during the LGM

Photogeneration of α‑Bimetalloid Radicals via Selective Activation of Multifunctional C1 Units

Light-driven strategies that enable the chemoselective activation of a specific bond in multifunctional systems are comparatively underexplored in comparison to transition-metal-based technologies, yet desirable when considering the controlled exploration of chemical space. With the current drive to discover next-generation therapeutics, reaction design that enables the strategic incorporation of an sp 3 carbon center, containing multiple synthetic handles for the subsequent exploration of chemical space would be highly enabling. Here, we describe the photoactivation of ambiphilic C1 units to generate α-bimetalloid radicals using only a Lewis base and light source to directly activate the C–I bond. Interception of these transient radicals with various SOMOphiles enables the rapid synthesis of organic scaffolds containing synthetic handles (B, Si, and Ge) for subsequent orthogonal activation. In-depth theoretical and mechanistic studies reveal the prominent role of 2,6-lutidine in forming a photoactive charge transfer complex and in stabilizing in situ generated iodine radicals, as well as the influential role of the boron p-orbital in the activation/weakening of the C–I bond. This simple and efficient methodology enabled expedient access to functionalized 3D frameworks that can be further derivatized using available technologies for C–B and C–Si bond activation

Prevalence of true vein graft aneurysms: Implications for aneurysm pathogenesis

AbstractBackground: Circumstantial evidence suggests that arterial aneurysms have a different cause than atherosclerosis and may form part of a generalized dilating diathesis. The aim of this study was to compare the rates of spontaneous aneurysm formation in vein grafts performed either for popliteal aneurysms or for occlusive disease. The hypothesis was that if arterial aneurysms form a part of a systemic process, then the rates of vein graft aneurysms should be higher for patients with popliteal aneurysms than for patients with lower limb ischemia caused by atherosclerosis. Methods: Infrainguinal vein grafting procedures performed from 1990 to 1995 were entered into a prospective audit and graft surveillance program. Aneurysmal change was defined as a focal increase in the graft diameter of 1.5 cm or greater, excluding false aneurysms and dilatations after graft angioplasty. Results: During the study period, 221 grafting procedures were performed in 200 patients with occlusive disease and 24 grafting procedures were performed in 21 patients with popliteal aneurysms. Graft surveillance revealed spontaneous aneurysm formation in 10 of the 24 bypass grafts (42%) for popliteal aneurysms but in only 4 of the 221 grafting procedures (2%) that were performed for chronic lower limb ischemia. Conclusion:This study provides further evidence that aneurysmal disease is a systemic process, and this finding has clinical implications for the treatment of popliteal aneurysms. (J Vasc Surg 1999;29:403-8.

Bariatric surgery tourism in the COVID-19 era

Background: Since the start of the Covid-19 pandemic primary and secondary health care services in Northern Ireland have observed an increase in the number of patients who have had bariatric surgery outside of the UK. This study sought to estimate the frequency of bariatric surgery tourism and to audit indications, blood monitoring and medical complications.Methods: All primary care centres within the Western Health Social Care Trust (WHSCT) were invited to document the number of patients undergoing bariatric surgery between January 1, 2017 and December 31, 2022. For one primary care centre, patients who underwent bariatric surgery were assessed against the National Institute of Health and Clinical Excellence (NICE) guideline indications for bariatric surgery. In addition, the blood monitoring of these patients was audited against the British Obesity and Metabolic Surgery Society (BOMSS) guidelines for up to two years following surgery. Medical contacts for surgical complications of bariatric surgery were recorded.Results: Thirty-five of 47 (74.5%) GP surgeries replied to the survey, representing 239,961 patients among 325,126 registrations (73.8%). In the six year study period 463 patients had reported having bariatric surgery to their GP. Women were more likely to have had bariatric surgery than men (85.1% versus 14.9%). There was a marked increase in the number of patients undergoing bariatric surgery with each year of the study (p&lt;0.0001 chi square for trend). Twenty-one of 47 patients (44.7%) evaluated in one primary care centre fulfilled NICE criteria for bariatric surgery. The level of three-month monitoring ranged from 23% (for vitamin D) to 89% (electrolytes), but decreased at two years to 9% (vitamin D) and 64% (electrolytes and liver function tests). Surgical complication prevalence from wound infections was 19% (9 of 44). Antidepressant medications were prescribed for 23 of 47 patients (48.9%).Conclusions: The WHSCT has experienced a growing population of patients availing of bariatric surgery outside of the National Health Service. In view of this and the projected increase in obesity prevalence, a specialist obesity management service is urgently required in Northern Ireland.</p

New ages from Boomplaas Cave, South Africa, provide increased resolution on late/terminal Pleistocene human behavioural variability

Abstract: Boomplaas Cave, South Africa, contains a rich archaeological record, with evidence of human occupation from approximately 66,000 years ago until the protohistoric period. Notwithstanding a long history of research at the site, its existing chronology can benefit from revision. Many of the site’s members are currently delimited by only a single conventional radiocarbon date and some of the existing dates were measured on materials now known to be unsuitable for radiocarbon dating. Here we present the results of an ongoing effort to redate key late/terminal Pleistocene sequences in southern Africa. This paper presents a Bayesian-modelled radiocarbon chronology for the late/terminal Pleistocene horizons at Boomplaas. Our model incorporates previously published radiocarbon dates as well as new accelerator mass spectrometry ages. We also present archaeological evidence to examine in greater detail than was previously possible the nature of occupation patterning across the late/terminal Pleistocene and to assess technological change across two of the site’s Last Glacial Maximum (LGM) members. The new dates and archaeological data confirm that the site was occupied in a series of low intensity events in the early LGM and immediately thereafter. The site was occupied intensively in the terminal Pleistocene in line with major changes in palaeoenvironments and sea-level fluctuations. The lithic data show the use of variable technological strategies in contexts of shifting mobility and site occupation patterns. Our discussion informs upon huntergatherer behavioural variability that did not, and should not be expected to, reflect the strategies adopted and adapted by a handful of well-known arid-zone hunter-gatherers in the twentieth-century Kalahari

Amino acid-dependent cMyc expression is essential for NK cell metabolic and functional responses in mice

Natural killer (NK) cells are lymphocytes with important anti-tumour functions. Cytokine activation of NK cell glycolysis and oxidative phosphorylation (OXPHOS) are essential for robust NK cell responses. However, the mechanisms leading to this metabolic phenotype are unclear. Here we show that the transcription factor cMyc is essential for IL-2/IL-12-induced metabolic and functional responses in mice. cMyc protein levels are acutely regulated by amino acids; cMyc protein is lost rapidly when glutamine is withdrawn or when system L-amino acid transport is blocked. We identify SLC7A5 as the predominant system L-amino acid transporter in activated NK cells. Unlike other lymphocyte subsets, glutaminolysis and the tricarboxylic acid cycle do not sustain OXPHOS in activated NK cells. Glutamine withdrawal, but not the inhibition of glutaminolysis, results in the loss of cMyc protein, reduced cell growth and impaired NK cell responses. These data identify an essential role for amino acid-controlled cMyc for NK cell metabolism and function

From BASE-ASIA Toward 7-SEAS: A Satellite-Surface Perspective of Boreal Spring Biomass-Burning Aerosols and Clouds in Southeast Asia

In this paper, we present recent field studies conducted by NASA's SMART-COMMIT (and ACHIEVE, to be operated in 2013) mobile laboratories, jointly with distributed ground-based networks (e.g., AERONET, http://aeronet.gsfc.nasa.gov/ and MPLNET, http://mplnet.gsfc.nasa.gov/) and other contributing instruments over northern Southeast Asia. These three mobile laboratories, collectively called SMARTLabs (cf. http://smartlabs.gsfc.nasa.gov/, Surface-based Mobile Atmospheric Research & Testbed Laboratories) comprise a suite of surface remote sensing and in-situ instruments that are pivotal in providing high spectral and temporal measurements, complementing the collocated spatial observations from various Earth Observing System (EOS) satellites. A satellite-surface perspective and scientific findings, drawn from the BASE-ASIA (2006) field deployment as well as a series of ongoing 7-SEAS (2010-13) field activities over northern Southeast Asia are summarized, concerning (i) regional properties of aerosols from satellite and in situ measurements, (ii) cloud properties from remote sensing and surface observations, (iii) vertical distribution of aerosols and clouds, and (iv) regional aerosol radiative effects and impact assessment. The aerosol burden over Southeast Asia in boreal spring, attributed to biomass burning, exhibits highly consistent spatial and temporal distribution patterns, with major variability arising from changes in the magnitude of the aerosol loading mediated by processes ranging from large-scale climate factors to diurnal meteorological events. Downwind from the source regions, the tightly coupled-aerosolecloud system provides a unique, natural laboratory for further exploring the micro- and macro-scale relationships of the complex interactions. The climatic significance is presented through large-scale anti-correlations between aerosol and precipitation anomalies, showing spatial and seasonal variability, but their precise cause-and-effect relationships remain an open-ended question. To facilitate an improved understanding of the regional aerosol radiative effects, which continue to be one of the largest uncertainties in climate forcing, a joint international effort is required and anticipated to commence in springtime 2013 in northern Southeast Asia