173 research outputs found
Queue-munity engagement: Collaborative Event Ethnography at the Antiques Roadshow in Kent
Using Collaborative Event Ethnography as a research method, a team of 21 researchers conducted fieldwork at the Antiques Roadshow in Ightham Mote, Kent. This article reflects on the experience of queuing at the event and how it was experienced and discussed by researchers and participants. Drawing upon Mol, the article approaches the practice of queuing as involving an inherent multiplicity of often contradictory experiences through which idealised, Second World War-related understandings of British queuing practice are simultaneously confirmed and challenged. Through multiple participants viewing the queue from within and outside we were able to capture the processes of community-building, curation, management, rule-maintenance and rule-bending within the social life of the queue. In demonstrating this multiplicity Collaborative Event Ethnography is shown to be an excellent research tool for capturing short-term, large-scale events while also highlighting the simultaneous simplicity and complexity of social interactions and social norms within queues
Development of a Type 2 Diabetes Risk Model From a Panel of Serum Biomarkers From the Inter99 Cohort
Permafrost conditions in the Mediterranean region since the Last Glaciation.
Cold-climate geomorphological processes today in the Mediterranean region are only distributed in the highest mountain environments. However, climate condition prevailing during the Late Pleistocene and Holocene have conditioned significant spatio-temporal variations of the glacial and periglacial domain in these mountains, including permafrost. In this communication we examine permafrost condition in the Mediterranean region taking into account five periods: Last Glaciation, deglaciation, Holocene, Little Ice Age (LIA) and present-day. The distribution of currently inactive permafrost-derived landforms and sedimentary records indicates that the permafrost elevation during the Last Glaciation was ca. 1000 m lower than present. Permafrost was also widespread in non-glaciated slopes above the snowline forming rock glaciers and block streams, as well as in relatively flat summit areas where meter-sized stone circles developed. As in most areas of the Northern Hemisphere, the deglaciation in the Mediterranean region started ca. 19-20 ka. The exposed terrain by retreating glaciers was affected by paraglacial dynamics and intense periglacial processes, mostly associated with permafrost condition. Many rock glaciers, protalus lobes and block streams formed in these recently deglaciated environments, becoming gradually inactive as temperatures rose during the Bølling-Allerød. Following the Younger Dryas glacial advance, the last massive deglaciation in Mediterranean mountains took place during the Early Holocene together with a progressive shift of the periglacial belt to higher elevations. It is unlikely that widespread permafrost have existed in Mediterranean mountains during the Holocene, except in the highest massifs exceeding 2500-3000 m. The colder climate prevailing during the LIA favoured a minor glacial advance and the spatial expansion of permafrost, with the development of new protalus lobes and rock glaciers in the highest massifs. Finally, the warming started during the second half of the 19th century has led to glacial retreat and/or complete melting, increased paraglacial activity, migration of periglacial processes to the highest lands and degradation of alpine permafrost along with geoecological changes
Classification of hepatitis C virus into six major genotypes and a series of subtypes by phylogenetic analysis of the NS-5 region
Hepatitis C virus (HCV) shows substantial nucleotide sequence diversity distributed throughout the viral genome, with many variants showing only 68 to 79 % overall sequence similarity to one another. Phylogenetic analysis ofnucleofide sequences derived from part of the gene encoding a non-structural protein (NS-5) has provided evidence for six major genotypes of HCV amongst a worldwide collection of 76 samples from HCV-infected blood donors and patients with chronic hepatitis. Many of these HCV types comprised a number of more closely related subtypes, leading to a current total of 11 genetically distinct viral populations. Phylo-genetic analysis of other regions of the viral genome produced relationships between published sequences equivalent to those found in NS-5, apart from the more highly conserved 5 ' non-coding region in which only the six major HCV types, but not subtypes, could be differentiated. A new nomenclature for HCV variants is proposed in this communication that reflects the twotiered nature of sequence differences between different viral isolates. The scheme classifies all known HCV variants to date, and describes criteria that would enable new variants to be assigned within the classification as they are discovered
A Simple, Inexpensive Device for Nucleic Acid Amplification without Electricity—Toward Instrument-Free Molecular Diagnostics in Low-Resource Settings
Molecular assays targeted to nucleic acid (NA) markers are becoming increasingly important to medical diagnostics. However, these are typically confined to wealthy, developed countries; or, to the national reference laboratories of developing-world countries. There are many infectious diseases that are endemic in low-resource settings (LRS) where the lack of simple, instrument-free, NA diagnostic tests is a critical barrier to timely treatment. One of the primary barriers to the practicality and availability of NA assays in LRS has been the complexity and power requirements of polymerase chain reaction (PCR) instrumentation (another is sample preparation).In this article, we investigate the hypothesis that an electricity-free heater based on exothermic chemical reactions and engineered phase change materials can successfully incubate isothermal NA amplification assays. We assess the heater's equivalence to commercially available PCR instruments through the characterization of the temperature profiles produced, and a minimal method comparison. Versions of the prototype for several different isothermal techniques are presented.We demonstrate that an electricity-free heater based on exothermic chemical reactions and engineered phase change materials can successfully incubate isothermal NA amplification assays, and that the results of those assays are not significantly different from ones incubated in parallel in commercially available PCR instruments. These results clearly suggest the potential of the non-instrumented nucleic acid amplification (NINA) heater for molecular diagnostics in LRS. When combined with other innovations in development that eliminate power requirements for sample preparation, cold reagent storage, and readout, the NINA heater will comprise part of a kit that should enable electricity-free NA testing for many important analytes
Africa’s response to the COVID-19 pandemic : A review of the nature of the virus, impacts and implications for preparedness
Background: COVID-19 continues to wreak havoc in different countries across the world, claiming thousands of lives, increasing morbidity and disrupting lifestyles. The global scientific community is in urgent need of relevant evidence, to understand the challenges and knowledge gaps, as well as the opportunities to contain the spread of the virus. Considering the unique socio-economic, demographic, political, ecological and climatic contexts in Africa, the responses which may prove to be successful in other regions may not be appropriate on the continent. This paper aims to provide insight for scientists, policy makers and international agencies to contain the virus and to mitigate its impact at all levels. Methods: The Affiliates of the African Academy of Sciences (AAS), came together to synthesize the current evidence, identify the challenges and opportunities to enhance the understanding of the disease. We assess the potential impact of this pandemic and the unique challenges of the disease on African nations. We examine the state of Africa’s preparedness and make recommendations for steps needed to win the war against this pandemic and combat potential resurgence. Results: We identified gaps and opportunities among cross-cutting issueswhich must be addressed or harnessed in this pandemic. Factors such as the nature of the virus and the opportunities for drug targeting, point of care diagnostics, health surveillance systems, food security, mental health, xenophobia and gender-based violence, shelter for the homeless, water and sanitation, telecommunications challenges, domestic regional coordination and financing. Conclusion: Based on our synthesis of the current evidence, while there are plans for preparedness in several African countries, there are significant limitations. A multi-sectoral efforts from the science, education, medical, technology, communication, business, and industry sectors, as well as local communities, must work collaboratively to assist countries in order to win this fight
Correlation between serum HCV RNA and aminotransferase levels in patients with chronic HCV infection
Cross-sectional studies on the correlation between serum hepatitis C virus (HCV) RNA and alanine aminotransferase (ALT) levels in patients with chronic hepatitis C have yielded conflicting results. We conducted a longitudinal study to examine the correlation between HCV viremia and serum ALT levels in individual patients over time. Serial samples (mean 9) from 25 patients with chronic HCV infection, including interferon-treated and untreated immunocompetent and immunosuppressed patients, collected over a period of 1–4.8 years (mean 2.6 years) were tested for HCV RNA and ALT levels using a highly reproducible quantitative (bDNA) assay. A significant correlation was found between serum HCV RNA and ALT levels in the patients who received IFN therapy, but no correlation was observed in the untreated patients. Among the untreated patients, the immunosuppressed patients had significantly higher HCV RNA levels (39±4 vs 3.6±8 Meq/ml, P <0.0001) but significantly lower ALT (56±11 vs 97±12 units/liter, P =0.03) levels when compared to the immunocompetent ones. In summary, we found no correlation between serum HCV RNA and ALT levels in chronic hepatitis C patients who are not receiving interferon therapy. Immunosuppression results in higher HCV RNA but lower ALT levels.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44425/1/10620_2005_Article_BF02071402.pd
Dipstick Test for Rapid Diagnosis of Shigella dysenteriae 1 in Bacterial Cultures and Its Potential Use on Stool Samples
International audienceBACKGROUND: We describe a test for rapid detection of S. dysenteriae 1 in bacterial cultures and in stools, at the bedside of patients. METHODOLOGY/PRINCIPAL FINDINGS: The test is based on the detection of S. dysenteriae 1 lipopolysaccharide (LPS) using serotype 1-specific monoclonal antibodies coupled to gold particles and displayed on a one-step immunochromatographic dipstick. A concentration as low as 15 ng/ml of LPS was detected in distilled water and in reconstituted stools in 10 minutes. In distilled water and in reconstituted stools, an unequivocal positive reaction was obtained with 1.6×10⁶ CFU/ml and 4.9×10⁶ CFU/ml of S. dysenteriae 1, respectively. Optimal conditions to read the test have been determined to limit the risk of ambiguous results due to appearance of a faint yellow test band in some negative samples. The specificity was 100% when tested with a battery of Shigella and unrelated strains in culture. When tested on 328 clinical samples in India, Vietnam, Senegal and France by laboratory technicians and in Democratic Republic of Congo by a field technician, the specificity (312/316) was 98.7% (95% CI:96.6-99.6%) and the sensitivity (11/12) was 91.7% (95% CI:59.8-99.6%). Stool cultures and the immunochromatographic test showed concordant results in 98.4 % of cases (323/328) in comparative studies. Positive and negative predictive values were 73.3% (95% CI:44.8-91.1%) and 99.7% (95% CI:98-100%). CONCLUSION: The initial findings presented here for a simple dipstick-based test to diagnose S. dysenteriae 1 demonstrates its promising potential to become a powerful tool for case management and epidemiological surveys
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