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A consideration of the mycotoxin hypothesis with special reference to the mycoflora of maize, sorghum, wheat and groundnuts (G105)
This review attempts to trace the connection between the mycology of foodstuffs and the onset of disease due to the toxins that various fungi produce within those foodstuffs. The association of fungal activity with the occurrence of various disease syndromes in man and animals has only recently been recognised. Possibly this is because the epidemiology of mycotoxins involves more than one scientific discipline. and the collation of knowledge has inevitably been slow. Also the chronic long term effects of mycotoxin poisoning may have been obviated by better preventive measures in the developed countries; certainly it is the Third World countries which have contributed most to our understanding of this subject. Because of the relative remoteness of these areas from the main areas of research however, it has taken longer to collect sufficient data, especially that pertaining to the human situation
Are complex systems hard to evolve?
Evolutionary complexity is here measured by the number of trials/evaluations
needed for evolving a logical gate in a non-linear medium. Behavioural
complexity of the gates evolved is characterised in terms of cellular automata
behaviour. We speculate that hierarchies of behavioural and evolutionary
complexities are isomorphic up to some degree, subject to substrate specificity
of evolution and the spectrum of evolution parameters
A field evaluation of the Hardy TB MODS Kit™ for the rapid phenotypic diagnosis of tuberculosis and multi-drug resistant tuberculosis.
BACKGROUND: Even though the WHO-endorsed, non-commercial MODS assay offers rapid, reliable TB liquid culture and phenotypic drug susceptibility testing (DST) at lower cost than any other diagnostic, uptake has been patchy. In part this reflects misperceptions about in-house assay quality assurance, but user convenience of one-stop procurement is also important. A commercial MODS kit was developed by Hardy Diagnostics (Santa Maria, CA, USA) with PATH (Seattle, WA, USA) to facilitate procurement, simplify procedures through readymade media, and enhance safety with a sealing silicone plate lid. Here we report the results from a large-scale field evaluation of the MODS kit in a government service laboratory. METHODS & FINDINGS: 2446 sputum samples were cultured in parallel in Lowenstein-Jensen (LJ), conventional MODS and in the MODS kit. MODS kit DST was compared with conventional MODS (direct) DST and proportion method (indirect) DST. 778 samples (31.8%) were Mycobacterium tuberculosis culture-positive. Compared to conventional MODS the sensitivity, specificity, positive, and negative predictive values (95% confidence intervals) of the MODS Kit were 99.3% (98.3-99.8%), 98.3% (97.5-98.8%), 95.8% (94.0-97.1%), and 99.7% (99.3-99.9%). Median (interquartile ranges) time to culture-positivity (and rifampicin and isoniazid DST) was 10 (9-13) days for conventional MODS and 8.5 (7-11) for MODS Kit (p<0.01). Direct rifampicin and isoniazid DST in MODS kit was almost universally concordant with conventional MODS (97.9% agreement, 665/679 evaluable samples) and reference indirect DST (97.9% agreement, 687/702 evaluable samples). CONCLUSIONS: MODS kit delivers performance indistinguishable from conventional MODS and offers a convenient, affordable alternative with enhanced safety from the sealing silicone lid. The availability in the marketplace of this platform, which conforms to European standards (CE-marked), readily repurposed for second-line DST in the near future, provides a fresh opportunity for improving equity of access to TB diagnosis and first and second-line DST in settings where the need is greatest
Investigating the celebrity effect: the influence of well-liked celebrities on adults' implicit and explicit responses to brands
©American Psychological Association, 2018. This paper is not the copy of record and may not exactly replicate the authoritative document published in the APA journal. Please do not copy or cite without author's permission. The final article is available, upon publication, at: https://doi.org/10.1037/ppm0000199Celebrities are used within advertisements in an attempt to impact positively on consumers’ attitudes toward brands, purchase intentions, and ad believability. However, the findings from previous research on the effects of celebrity liking on brand evaluations have been mixed. In the study presented here, explicit and implicit responses to brands were more positive after pairing with well-liked celebrities (p < .01) and more positive than for brands paired with noncelebrities (p < .001). Participants also demonstrated a preference for celebrity-paired brands in their brand choices (p < .001). Participants’ general accuracy-based advertising skepticism was negatively correlated with explicit celebrity brand preferences (p < .05), whereas affect-based skepticism was negatively correlated with implicit (p < .05) preferences. These results are discussed in relation to the contextual and attitudinal factors that might trigger resistance to the effects of celebrity endorsement as well as the underlying psychological processes involved in responding to ads
Gas phase atomic metals in the circumstellar envelope of IRC+10216
We report the results of a search for gas phase atomic metals in the
circumstellar envelope of the AGB carbon star IRC+10216. The search was made
using high resolution (R=50000) optical absorption spectroscopy of a backgound
star that probes the envelope on a line of sight 35" from the center. The metal
species that we detect in the envelope include NaI, KI, CaI, CaII, CrI, and
FeI, with upper limits for AlI, MnI, TiI, TiII, and SrII. The observations are
used to determine the metal abundances in the gas phase and the condensation
onto grains. The metal depletions range from a factor of 5 for Na to 300 for
Ca, with some similarity to the depletion pattern in interstellar clouds. Our
results directly constrain the condensation efficiency of metals in a
carbon-rich circumstellar envelope and the mix of solid and gas phase metals
returned by the star to the ISM. The abundances of the uncondensed metal atoms
that we observe are typically larger than the abundances of the metal-bearing
molecules detected in the envelope. The metal atoms are therefore the major
metal species in the gas phase and likely play a key role in the metal
chemistry.Comment: 11 pages, 8 Figures. Accepted by Astronomy and Astrophysic
A Conjecture about Hadrons
We conjecture that in the chiral limit of QCD the spectrum of hadrons is
comprised of decoupled, reducible chiral multiplets. A simple rule is developed
which identifies the chiral representations filled out by the ground-state
hadrons. Our arguments are based on the algebraic structure of superconvergence
relations derived by Weinberg from the high-energy behavior of pion-hadron
scattering amplitudes.Comment: 15 pages LaTe
Comparison of Relativistic Nucleon-Nucleon Interactions
We investigate the difference between those relativistic models based on
interpreting a realistic nucleon-nucleon interaction as a perturbation of the
square of a relativistic mass operator and those models that use the method of
Kamada and Gl\"ockle to construct an equivalent interaction to add to the
relativistic mass operator. Although both models reproduce the phase shifts and
binding energy of the corresponding non-relativistic model, they are not
scattering equivalent. The example of elastic electron-deuteron scattering in
the one-photon-exchange approximation is used to study the sensitivity of
three-body observables to these choices. Our conclusion is that the differences
in the predictions of the two models can be understood in terms of the
different ways in which the relativistic and non-relativistic -matrices are
related. We argue that the mass squared method is consistent with conventional
procedures used to fit the Lorentz-invariant cross section as a function of the
laboratory energy.Comment: Revtex 13 pages, 5 figures, corrected some typo
Rapid monitoring of anti-tuberculosis therapy using fluorescein diacetate microscopy: a simple method to determine infectiousness and screen for drug resistance
Background: Tuberculosis treatment and infection control are hampered by difficulty assessing mycobacterial viability to determine infectiousness and early treatment response. TB culture takes weeks; molecular tests are technically demanding; and acid-fast staining cannot differentiate live from dead tuberculosis. / Objectives: To develop and evaluate a simple slide-microscopy test to rapidly determine tuberculosis viability. / Methods: A protocol was optimized to stain viable but not dead tuberculosis in decontaminated sputum dried onto microscope slides and stained with the vital stain fluorescein diacetate (FDA). The reliability of this FDA slide microscopy for determining the concentration of viable tuberculosis in sputum was then compared with quantitative culture. / Results-laboratory evaluation: In untreated patients, tuberculosis auramine staining was unaffected whether sputum was fresh or had been sterilized by boiling, whereas FDA stained only un-boiled, viable tuberculosis. Quantification of viable tuberculosis by culture was reliably predicted by FDA, but not by auramine microscopy. / Results-clinical evaluation : Sequential sputums were collected from 35 patients before and after 3, 6 and 9 days of first-line tuberculosis treatment. Culture quantification of viable mycobacteria in sputum was predicted by slide microscopy with FDA (r2=0.77) but not auramine (r2=0.33). Quantification of viable tuberculosis in sputum by both quantitative culture and FDA microscopy fell 10-100 fold during the first nine days of treatment in all patients with drug-susceptible tuberculosis, whereas there was little change for patients with MDRTB. Specifically, 70% of samples from patients with drug-susceptible tuberculosis had a decline in the FDA count of viable tuberculosis of at least 0.2 logs/treatment-day, compared with none of the samples from MDRTB patients (P1 month required for culture. This simple and inexpensive technique rapidly assessed patient infectiousness on treatment, potentially guiding infection control measures. FDA staining also revealed differences in early treatment response between non-MDR and MDRTB and may allow early field screening for MDRTB and impending treatment failure
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