1,627 research outputs found
Somatic embryogenesis and plant regeneration from cotyledon tissue of Arachis hypogaea L.
Tissue culture techniques are useful for ex situ conservation of rare, endemic orthreatened plant species. This report describes a protocol for somatic embryogenesis ofpeanut (Arachis hypogaea L.) through cotyledon explants. Only 10% of the explants werecontaminated by using this material to start the in vitro culture. The highest frequency(35.4%) of embryogenic calli induction was observed on MS medium supplemented with0.50 mg/l KIN in combination with 0.10 mg/l 2,4,-D. the percentage response for embryogenicproliferation increased in the medium supplemented with GA3(0.20 mg/l) and 1.0 mg/l BA.The regenerated embryos were successfully transferred to the embryo development mediumand transferred to the trays after the development of secondary and tertiary rootdevelopment
The Controversies and Difficulties of Diagnosing Primary Ciliary Dyskinesia
We welcome the correspondence from Lavie and Amirav (1), highlighting the difficulties diagnosing primary ciliary dyskinesia (PCD) and the role of high-speed video analysis (HSVA). As members of the European Respiratory Society (ERS) PCD Diagnostic Task Force (2) and/or large PCD Centres, we agree that HSVA has an important role that is not recognized by the American Thoracic Society (ATS) PCD Diagnostic Guideline (3). This risks a large proportion of false-negative âmissedâ diagnoses and a sizable number of false-positive cases; we make additional important observations.</div
Secondary organic aerosol formation from in-use motor vehicle emissions using a potential aerosol mass reactor.
Secondary organic aerosol (SOA) formation from in-use vehicle emissions was investigated using a potential aerosol mass (PAM) flow reactor deployed in a highway tunnel in Pittsburgh, Pennsylvania. Experiments consisted of passing exhaust-dominated tunnel air through a PAM reactor over integrated hydroxyl radical (OH) exposures ranging from ⌠0.3 to 9.3 days of equivalent atmospheric oxidation. Experiments were performed during heavy traffic periods when the fleet was at least 80% light-duty gasoline vehicles on a fuel-consumption basis. The peak SOA production occurred after 2-3 days of equivalent atmospheric oxidation. Additional OH exposure decreased the SOA production presumably due to a shift from functionalization to fragmentation dominated reaction mechanisms. Photo-oxidation also produced substantial ammonium nitrate, often exceeding the mass of SOA. Analysis with an SOA model highlight that unspeciated organics (i.e., unresolved complex mixture) are a very important class of precursors and that multigenerational processing of both gases and particles is important at longer time scales. The chemical evolution of the organic aerosol inside the PAM reactor appears to be similar to that observed in the atmosphere. The mass spectrum of the unoxidized primary organic aerosol closely resembles ambient hydrocarbon-like organic aerosol (HOA). After aging the exhaust equivalent to a few hours of atmospheric oxidation, the organic aerosol most closely resembles semivolatile oxygenated organic aerosol (SV-OOA) and then low-volatility organic aerosol (LV-OOA) at higher OH exposures. Scaling the data suggests that mobile sources contribute ⌠2.9 ± 1.6 Tg SOA yr(-1) in the United States, which is a factor of 6 greater than all mobile source particulate matter emissions reported by the National Emissions Inventory. This highlights the important contribution of SOA formation from vehicle exhaust to ambient particulate matter concentrations in urban areas
Locating poor livestock keepers at the global level for research and development targeting
P.K. Thornton, R.L. Kruska, P.M. Kristjanson, R.S. Reid and T.P. Robinson are ILRI authorsMany research and development agencies are committed to halving the number of people living in extreme poverty by 2015. Knowledge of where the poor are, and what characterises them, is patchy at best. Here we describe a global livestock and poverty mapping study designed to assist in targeting research and development activities concerning livestock. Estimates of the numbers of poor livestock keepers by production system and region are presented. While these estimates suffer from various problems, improvements in global databases are critical to improve the targeting of interventions that can meet the challenges posed by poverty and to chart progress against international development indicators
Cattle trypanosomiasis in Africa to 2030
Trypanosomiasis diseases are caused by single-cell organisms and affect both humans and cattle. This indicative study modelled the effect of climate change and population growth on the future range of tsetse flies, their main vector, in sub- Saharan Africa. Projected climate change to 2030 has a limited effect on their distribution. Population growth has more significant consequences, mainly caused by the land-use change that accompanies it. It could reduce the area in which tsetse flies are found by 15% by 2030. The main effect would be in drier areas of western, eastern and southern Africa, and in Ethiopia. Humid areas would be less altered. The authors say that other factors such as disease control efforts and changing agricultural practices may also affect the future range of the flies and of the diseases with which they are associated
The most creative organization in the world? The BBC, 'creativity' and managerial style
The managerial styles of two BBC directors-general, John Birt and Greg Dyke, have often been contrasted but not so far analysed from the perspective of their different views of 'creative management'. This article first addresses the orthodox reading of 'Birtism'; second, it locates Dyke's 'creative' turn in the wider context of fashionable neo-management theory and UK government creative industries policy; third, it details Dyke's drive to change the BBC's culture; and finally, it concludes with some reflections on the uncertainties inherent in managing a creative organisation
Giant Cell Arteritis and COVID-19:Similarities and Discriminators. A Systematic Literature Review
OBJECTIVE: To identify shared and distinct features of giant cell arteritis (GCA) and coronavirus disease 2019(COVID-19) to reduce diagnostic errors that could cause delays in correct treatment. METHODS: Two systematic literature reviews determined the frequency of clinical features of GCA and COVID-19 in published reports. Frequencies in each disease were summarized using medians and ranges. RESULTS: Headache was common in GCA but was also observed in COVID-19 (GCA 66%, COVID-19 10%). Jaw claudication or visual loss (43% and 26% in GCA, respectively) generally were not reported in COVID-19. Both diseases featured fatigue (GCA 38%, COVID-19 43%) and elevated inflammatory markers (C-reactive protein [CRP] elevated in 100% of GCA, 66% of COVID-19), but platelet count was elevated in 47% of GCA but only 4% of COVID-19 cases. Cough and fever were commonly reported in COVID-19 and less frequently in GCA (cough, 63% for COVID-19 vs 12% for GCA; fever, 83% for COVID-19 vs 27% for GCA). Gastrointestinal upset was occasionally reported in COVID-19 (8%), rarely in GCA (4%). Lymphopenia was more common in COVID-19 than GCA (53% in COVID-19, 2% in GCA). Alteration of smell and taste have been described in GCA but their frequency is unclear. CONCLUSION: Overlapping features of GCA and COVID-19 include headache, fever, elevated CRP and cough. Jaw claudication, visual loss, platelet count and lymphocyte count may be more discriminatory. Physicians should be aware of the possibility of diagnostic confusion. We have designed a simple checklist to aid evidence-based evaluation of patients with suspected GCA
Medical imaging for plantar heel pain:a systematic review and meta-analysis
BACKGROUND: Medical imaging can be used to assist with the diagnosis of plantar heel pain. The aim of this study was to synthesise medical imaging features associated with plantar heel pain. METHODS: This systematic review and meta-analysis conducted searches in MEDLINE, CINAHL, SPORTDiscus, Embase and the Cochrane Library from inception to 12th February 2021. Peer-reviewed articles of cross-sectional observational studies written in English that compared medical imaging findings in adult participants with plantar heel pain to control participants without plantar heel pain were included. Study quality and risk of bias was assessed using the National Institutes of Health quality assessment tool for observational cohort and cross-sectional studies. Sensitivity analyses were conducted where appropriate to account for studies that used unblinded assessors. RESULTS: Forty-two studies (2928 participants) were identified and included in analyses. Only 21% of studies were rated âgoodâ on quality assessment. Imaging features associated with plantar heel pain included a thickened plantar fascia (on ultrasound and MRI), abnormalities of the plantar fascia (on ultrasound and MRI), abnormalities of adjacent tissue such as a thickened loaded plantar heel fat pad (on ultrasound), and a plantar calcaneal spur (on x-ray). In addition, there is some evidence from more than one study that there is increased hyperaemia within the fascia (on power Doppler ultrasound) and abnormalities of bone in the calcaneus (increased uptake on technetium-99âm bone scan and bone marrow oedema on MRI). CONCLUSIONS: People with plantar heel pain are more likely to have a thickened plantar fascia, abnormal plantar fascia tissue, a thicker loaded plantar heel fat pad, and a plantar calcaneal spur. In addition, there is some evidence of hyperaemia within the plantar fascia and abnormalities of the calcaneus. Whilst these medical imaging features may aid with diagnosis, additional high-quality studies investigating medical imaging findings for some of these imaging features would be worthwhile to improve the precision of these findings and determine their clinical relevance. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13047-021-00507-2
Dr. Conway et al reply
We thank Sauret et al for their interest in our systematic literature review that explored potential diagnostic confusion between giant cell arteritis (GCA) and the coronavirus disease 2019 (COVID-19). This was a particularly important consideration during the early months of the COVID-19 pandemic, when community testing for SARS-CoV-2 was limited and diagnostic tests for GCA were restricted or unavailable due to redeployment of staff.</p
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