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Black dyes for coir fibre: 3 practical considerations
Earlier trials on Synacril Black A, Benzamin Black DS 167% and Suprexcel Black VY- three possible substitute dyes for Chlorazol Black E -showed the effect of variations in dyebath conditions on the amount of dye deposited on coir (Canning, A. J., Jarman, C. G. and Mykoluk, S. M. (1979) Black dyes for coir fibre. Part 2. Evaluation of selected dyes. Report of the Tropical Products Institute, L52). Further trials, in which both different concentrations of dye in the bath, and a standing bath were used, have now been carried out to obtain additional data on the exhaustion characteristics of the three dyes. Additionally, the effect of variations in dyebath conditions on the quality of colour, and the amount of each of the three dyes that needs to be deposited on to the fibre to produce an acceptable black, have been assessed. With all three dyes, dyebath exhaustion was approached more slowly with increased dyebath concentration. As a consequence, when additional dye is used, dyeing time must be increased to obtain the most efficient use of dye. Since the proportion of dye that exhausts from the bath is also reduced, particularly with the higher dyebath concentrations or the shorter dyeing times, increasingly large additions of dye are required in order to intensify the visual depth of shade. With low dyebath concentrations of the two direct dyes (Benzamin Black and Suprexcel Black), allowing the liquor to cool during dyeing could reduce heating costs since the exhaustion obtained after 1.5 hours at 95°C followed by cooling was similar to that obtained after 6 hours at 95°C. However, with deeper shades the opportunity for reducing heating costs by reducing dyeing time at 95°C and then cooling is less. The inclusion of sodium carbonate in the dyebath could also result in savings on dyestuff. When using a standing bath technique with Benzamin Black, significantly different exhaustion/time relationships were obtained with each batch of fibre. As a consequence there would be considerable practical difficulties in using this dye with this technique. On the other hand, the exhaustion of Suprexcel Black was only slightly affected by the use of replenished liquors and a standing bath technique could reduce costs. Because of its almost complete exhaustion, there would be no advantage in using a standing bath with the basic dye Synacril Black. All the dyes gave better light-fastness properties when they were concentrated at the periphery of the fibre rather than when they penetrated more deeply: however, staining of adjacent fabrics was greater. The distribution of the dye within the fibre did not affect the visual colour. All three dyes should produce black colours which are technically similar to those of commercial samples of black coir. The amounts which need to be deposited on the fibre to produce an acceptable black are estimated as approximately: Benzamin Black DS 167% - 19g per kilogram of fibre; Suprexcel Black VY - 22g per kilogram of fibre; Synacril Black A - 10g per kilogram of fibre. Fastness properties of the blacks vary with the dye and the technique used to apply it. Information on the development of optimum dyeing conditions is appended
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Social Investment. Tools for success: doing the right things and doing them right
Healthcare access for refugees in Greece: Challenges and opportunities
The arrival of more than one million refugees and migrants in Europe in 2015, most of whom transited through Greece, has placed significant strains on local health systems and demonstrated the need for preparedness to meet the immediate and longer-term health needs of arrivals in EU countries. Population movements will continue to occur and the need for cost effective, appropriate provision of both primary and secondary health services to meet these needs is key. The Global Compact on Migration was ratified in 2018 and forms an overarching, international agreement to address safe, orderly and regular migration which benefits refugees and migrants as well as host communities; however, it did not give due emphasis to health. In this manuscript, we explore the evolution of the health response for refugees in Greece over the last three years, the challenges faced at different times of the response and the efforts to integrate refugees into Greece’s health system
Do Surgical Trials Meet the Scientific Standards for Clinical Trials?
Unlike medications, the dissemination of surgical procedures into practice is not regulated. Before marketing, pharmaceutical products are required to be shown safe and efficacious in comparative clinical trials that use bias-reducing strategies designed to reduce the distortion of estimates of treatment effect by predispositions toward the investigational intervention or control. Unless an investigational device is involved, the corresponding process for surgical innovations is usually unregulated and therefore may not be based on adequate evidence. Given these differences, we sought to evaluate the state of clinical research on invasive procedures. We conducted a systematic review of publications from 1999 through 2008, which reported the results of studies evaluating the effects of invasive therapeutic procedures, focusing on trials that appeared to influence practice. Our objective was to determine what proportion of studies evaluating surgical procedures use a comparative clinical trial design and methods to control bias. This article reports our results and raises concerns about the methodologic, and therefore the ethical, quality of clinical research used to justify the implementation of surgical procedures into practice
Hormonal impact of the 17α-hydroxylase/C17,20-lyase inhibitor abiraterone acetate (CB7630) in patients with prostate cancer
A series of three dose escalating studies were conducted to investigate the ability of the 17-hydroxylase/C17,20-lyase inhibitor abiraterone acetate, to cause maximum suppression of testosterone synthesis when delivered to castrate and noncastrate males with prostate cancer. Study A was a single dose study in castrate males. Study B was a single dose study in noncastrate males and study C was a multiple dose study in noncastrate males. The drug was given orally in a once-daily dose and blood samples taken to assess pharmacokinetic (PK) parameters and hormone levels in all patients. The study drug was well tolerated with some variability in PKs. Suppression of testosterone levels to <0.14 nmol l-1 was seen in four out of six castrate males treated with a single dose of 500 mg. At 800 mg given days 1–12 in noncastrate males, target suppression was achieved in three out of three patients, but a two- to three-fold increase of Luteinising Hormone (LH) levels in two out of three patients overcame suppression within 3 days. All patients in the multiple dose study developed an abnormal response to a short Synacthen test by day 11, although baseline cortisol levels remained normal. This is the first report of the use of a specific 17-hydroxylase/17,20-lyase inhibitor in humans. Repeated treatment of men with intact gonadal function with abiraterone acetate at a dose of 800 mg can successfully suppress testosterone levels to the castrate range. However, this level of suppression may not be sustained in all patients due to compensatory hypersecretion of LH. The enhanced testosterone suppression achieved in castrate men merits further clinical study as a second-line hormonal treatment for prostate cancer. Adrenocortical suppression may necessitate concomitant administration of replacement glucocorticoid
Ab initio calculation of the neutron-proton mass difference
The existence and stability of atoms rely on the fact that neutrons are more
massive than protons. The measured mass difference is only 0.14\% of the
average of the two masses. A slightly smaller or larger value would have led to
a dramatically different universe. Here, we show that this difference results
from the competition between electromagnetic and mass isospin breaking effects.
We performed lattice quantum-chromodynamics and quantum-electrodynamics
computations with four nondegenerate Wilson fermion flavors and computed the
neutron-proton mass-splitting with an accuracy of kilo-electron volts,
which is greater than by standard deviations. We also determine the
splittings in the , , and isospin multiplets,
exceeding in some cases the precision of experimental measurements.Comment: 57 pages, 15 figures, 6 tables, revised versio
An assessment of the strength of knots and splices used as eye terminations in a sailing environment
Research into knots, splices and other methods of forming an eye termination has been limited, despite the fact that they are essential and strongly affect the performance of a rope. The aim of this study was to carry out a comprehensive initial assessment of the breaking strength of eye terminations commonly used in a sailing environment, thereby providing direction for further work in the field. Supports for use in a regular tensile testing machine were specially developed to allow individual testing of each sample and a realistic spread of statistical data to be obtained. Over 180 break tests were carried out on four knots (the bowline, double bowline, figure-of-eight loop and perfection loop) and two splices (three-strand eye splice and braid-on-braid splice). The factors affecting their strength were investigated. A statistical approach to the analysis of the results was adopted. The type of knot was found to have a significant effect on the strength. This same effect was seen in both types of rope construction (three-strand and braid-on-braid). Conclusions were also drawn as to the effect of splice length, eye size, manufacturer and rope diameter on the breaking strength of splices. Areas of development and further investigation were identified
Diagnostic accuracy of the T-MACS decision aid with a contemporary point-of-care troponin assay.
OBJECTIVES: The rapid turnaround time of point-of-care (POC) cardiac troponin (cTn) assays is highly attractive for crowded emergency departments (EDs). We evaluated the diagnostic accuracy of the Troponin-only Manchester Acute Coronary Syndromes (T-MACS) decision aid with a POC cTn assay. METHODS: In a prospective diagnostic accuracy study at eight EDs, we included patients with suspected acute coronary syndromes (ACS). Blood drawn on arrival and 3 hours later was analysed for POC cTnI (i-Stat, Abbott Point of Care). The primary outcome was a diagnosis of ACS, which included both an adjudicated diagnosis of acute myocardial infarction (AMI) based on serial laboratory cTn testing and major adverse cardiac events (death, AMI or coronary revascularisation) within 30 days. RESULTS: Of 716 patients included, 105 (14.7%) had ACS. Using serial POC cTnI concentrations over 3 hours could have 'ruled out' ACS in 198 (31.2%) patients with a sensitivity of 99.0% (95% CI 94.4% to 100.0%) and negative predictive value 99.5% (95% CI 96.5% to 99.9%). No AMIs were missed. T-MACS 'ruled in' ACS for 65 (10.4%) patients with a positive predictive value of 91.2% (95% CI 82.1% to 95.9%) and specificity 98.9% (97.6% to 99.6%). CONCLUSION: With a POC cTnI assay, T-MACS could 'rule out' ACS for approximately one-third of patients within 3 hours while 'ruling in' ACS for another 10%. The rapid turnaround time and portability of the POC assay make this an attractive pathway for use in crowded EDs or urgent care centres. Future work should also evaluate use in the prehospital environment
Marine environmental DNA biomonitoring reveals seasonal patterns in biodiversity and identifies ecosystem responses to anomalous climatic events
Marine ecosystems are changing rapidly as the oceans warm and become more acidic. The physical factors and the changes to ocean chemistry that they drive can all be measured with great precision. Changes in the biological composition of communities in different ocean regions are far more challenging to measure because most biological monitoring methods focus on a limited taxonomic or size range. Environmental DNA (eDNA) analysis has the potential to solve this problem in biological oceanography, as it is capable of identifying a huge phylogenetic range of organisms to species level. Here we develop and apply a novel multi-gene molecular toolkit to eDNA isolated from bulk plankton samples collected over a five-year period from a single site. This temporal scale and level of detail is unprecedented in eDNA studies. We identified consistent seasonal assemblages of zooplankton species, which demonstrates the ability of our toolkit to audit community composition. We were also able to detect clear departures from the regular seasonal patterns that occurred during an extreme marine heatwave. The integration of eDNA analyses with existing biotic and abiotic surveys delivers a powerful new long-term approach to monitoring the health of our world's oceans in the context of a rapidly changing climate
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