The origins and development of Zuwīla, Libyan Sahara: an archaeological and historical overview of an ancient oasis town and caravan centre

Zuwīla in southwestern Libya (Fazzān) was one of the most important early Islamic centres in the Central Sahara, but the archaeological correlates of the written sources for it have been little explored. This paper brings together for the first time a detailed consideration of the relevant historical and archaeological data, together with new AMS radiocarbon dates from several key monuments. The origins of the settlement at Zuwīla were pre-Islamic, but the town gained greater prominence in the early centuries of Arab rule of the Maghrib, culminating with the establishment of an Ibāḍī state ruled by the dynasty of the Banū Khaṭṭāb, with Zuwīla its capital. The historical sources and the accounts of early European travellers are discussed and archaeological work at Zuwīla is described (including the new radiocarbon dates). A short gazetteer of archaeological monuments is provided as an appendix. Comparisons and contrasts are also drawn between Zuwīla and other oases of the ash-Sharqiyāt region of Fazzān. The final section of the paper presents a series of models based on the available evidence, tracing the evolution and decline of this remarkable site

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

The effect of selection for rapid lean growth on the dietary lysine and energy requirements of pigs fed to scale

A line of pigs (S line) selected for weight of ham lean, a measure of lean growth, was compared with an unselected control line (C line) of common origin on a series of food regimens ranging in average daily intake from 23.7 to 27.2 MJ digestible energy and from 13.3 to 23.4 g total lysine. The comparison was made over a 12-week test period starting at 25 kg liveweight and measurements were made of growth rate, fat depth by ultrasonics and, from these, predicted weight of lean in the ham at the end of test. As energy and lysine in the diet were increased, growth rate and ham lean rose at rates and reached limits which were higher in the S than the C line. As a result of 4.4 standard deviations (SD) of selection differential accumulated over five generations of selection, the superiority of the S over the C line in ham lean ranged from 0.5 (SD) on a low energy-lysine diet to 2.7 SD on a high energy-lysine diet. Maximum growth rate and ham lean were reached in the S line on a diet which provided 1 MJ day-1 more digestible energy and 3 g day-1 more total lysine than the diet at which the maxima were reached in the C line. Increasing dietary energy raised fat depths in the C line and increasing lysine lowered fat depths in the S line. Pigs from both lines were most profitable on diets lower in energy and lysine levels than those which gave maximum growth. Net monetary returns were most responsive to changes in energy in the C line and to changes in lysine in the S line

The effect of selection for rapid lean growth on the dietary lysine and energy requirements of pigs fed to scale

A line of pigs (S line) selected for weight of ham lean, a measure of lean growth, was compared with an unselected control line (C line) of common origin on a series of food regimens ranging in average daily intake from 23.7 to 27.2 MJ digestible energy and from 13.3 to 23.4 g total lysine. The comparison was made over a 12-week test period starting at 25 kg liveweight and measurements were made of growth rate, fat depth by ultrasonics and, from these, predicted weight of lean in the ham at the end of test. As energy and lysine in the diet were increased, growth rate and ham lean rose at rates and reached limits which were higher in the S than the C line. As a result of 4.4 standard deviations (SD) of selection differential accumulated over five generations of selection, the superiority of the S over the C line in ham lean ranged from 0.5 (SD) on a low energy-lysine diet to 2.7 SD on a high energy-lysine diet. Maximum growth rate and ham lean were reached in the S line on a diet which provided 1 MJ day-1 more digestible energy and 3 g day-1 more total lysine than the diet at which the maxima were reached in the C line. Increasing dietary energy raised fat depths in the C line and increasing lysine lowered fat depths in the S line. Pigs from both lines were most profitable on diets lower in energy and lysine levels than those which gave maximum growth. Net monetary returns were most responsive to changes in energy in the C line and to changes in lysine in the S line

Assessment of current practice in the diagnosis and therapy of idiopathic pulmonary fibrosis

SummaryBackgroundThe consensus statement on the Diagnosis and Therapy of Idiopathic Pulmonary Fibrosis (IPF) formulated by the American Thoracic Society/European Respiratory Society (ATS/ERS) was published in 2000. Acceptance and implementation of these guidelines have not been assessed. We surveyed the fellows of the American College of Chest Physicians (FCCP) to establish current practice patterns regarding the diagnosis and therapy of IPF.MethodsWe electronically distributed a 32-item questionnaire to all 6443 pulmonary medicine board-certified Fellows of the American College of Chest Physicians. The response rate was 13%. Demographic characteristics were similar between respondents and non-respondents.ResultsSeventy-two percent of respondents were familiar with the ATS/ERS consensus statement and 63% found it clinically useful. However, a similar number of respondents indicated that an update is needed. Bronchoscopy and surgical lung biopsy are used infrequently. Forty-five percent of pulmonary physicians advocate providing only supportive care for patients outside of clinical trials. If pharmacological therapy is recommended, prednisone (either alone or in combination with azathioprine) or off-label agents are preferentially prescribed. Despite physician awareness (79%) of clinical trials, interested patients are not consistently referred (54%). A majority of respondents (61%) felt that lung transplantation represents the only effective therapy for IPF, and 86% refer their patients to lung transplant centers.ConclusionsThere is substantial variability among pulmonary physicians in the diagnosis and management of IPF. This may, in part, reflect the current lack of effective pharmacologic therapy. Updated practice guidelines are needed for the diagnosis and therapy of IPF