Evaluation of enzyme immunoassays in the diagnosis of camel (Camelus dromedarius) trypanosomiasis:a preliminary investigation

Three enzyme immunoassays were used for the serodiagnosis of Trypanosoma evansi in camels in the Sudan in order to evaluate their ability to discriminate between infected and non-infected animals. Two assays were used for the detection of trypanosomal antibodies, one using specific anti-camel IgG conjugate and another using a non-specific Protein A conjugate. The third assay detected the presence of trypanosomal antigens using anti-T. evansi antibodies in a double antibody sandwich assay. Inspection of the frequency distribution of assay results suggested that the ELISA for circulating trypanosomal antibodies using specific antisera and the ELISA for circulating antigens can distinguish between non-infected camels and infected camels exhibiting patent infections or not. The ELISA using Protein A conjugate to bind non-specifically to camel immunoglobulin did not appear to discriminate between infected and non-infected animals

Water fluoridation in Queensland, why not? Timing, circumstance, and the nature of 'The fluoridation of public water supplies Act (1963)'

During the last 52 years, almost all Queensland authorities have refused to implement artificial water fluoridation. Once again, the argument that Queensland is different suggests a cultural explanation for its fluoride status. This paper argues, however, that the reason lies with the Fluoridation of Public Water Supplies Act 1963 (Qld), which gives real power to the minister for Local Government, local authorities and 10 percent of electors, who can all request a referendum on fluoridation proposals. This law has given opponents of fluoridation tactical advantages, which they have used consistently

Constraining quasar host halo masses with the strength of nearby Lyman-alpha forest absorption

Using cosmological hydrodynamic simulations we measure the mean transmitted flux in the Lyman alpha forest for quasar sightlines that pass near a foreground quasar. We find that the trend of absorption with pixel-quasar separation distance can be fitted using a simple power law form including the usual correlation function parameters r_{0} and \gamma so that ( = \sum exp(-tau_eff*(1+(r/r_{0})^(-\gamma)))). From the simulations we find the relation between r_{0} and quasar mass and formulate this as a way to estimate quasar host dark matter halo masses, quantifying uncertainties due to cosmological and IGM parameters, and redshift errors. With this method, we examine data for ~3000 quasars from the Sloan Digital Sky Survey (SDSS) Data Release 3, assuming that the effect of ionizing radiation from quasars (the so-called transverse proximity effect) is unimportant (no evidence for it is seen in the data.) We find that the best fit host halo mass for SDSS quasars with mean redshift z=3 and absolute G band magnitude -27.5 is log10(M/M_sun) = 12.48^{+0.53}_{-0.89}. We also use the Lyman-Break Galaxy (LBG) and Lyman alpha forest data of Adelberger et al in a similar fashion to constrain the halo mass of LBGs to be log10(M/M_sun) = 11.13^{+0.39}_{-0.55}, a factor of ~20 lower than the bright quasars. In addition, we study the redshift distortions of the Lyman alpha forest around quasars, using the simulations. We use the quadrupole to monopole ratio of the quasar-Lyman alpha forest correlation function as a measure of the squashing effect. We find that this does not have a measurable dependence on halo mass, but may be useful for constraining cosmic geometry.Comment: 10 pages, 11 figures, submitted to MNRA

Appraising Forgeability and Surface Cracking in New Generation Cast and Wrought Superalloys

Surface cracking poses a major problem in industrial forging, but the scientific understanding of the phenomenon is hampered by the difficulty of replicating it in a laboratory setting. In this work, a novel laboratory-scale experimental method is presented to investigate forgeability in new generation cast and wrought superalloys. This new approach makes possible appraising the prevalence and severity of surface cracking by mimicking the die chilling effects characteristic of hot die forging. Two high γ′-reinforced alloys are used to explore this methodology. A Gleeble thermo-mechanical simulator is used to conduct hot compression tests following a non-isothermal cycle, with the aim to simulate the cooling of the near-surface regions during the forging process. FEA simulations, sample geometry design, and heat-treatments are used to ensure the correspondence between laboratory and real-scale forging. A wide range of surface cracking results are obtained for different forging temperatures and cooling rates—proving the soundness of the method. Surprisingly, samples heated up to higher initial temperatures typically show more extensive surface cracking. These findings indicate that—along with the local mechanical conditions of the forging—die-chilling effects and forging temperatures are paramount in controlling surface cracking, as they dictate the key variables governing the distribution and kinetics of γ′ formation

Resolved Sideband Cooling of a Micromechanical Oscillator

Micro- and nanoscale opto-mechanical systems provide radiation pressure coupling of optical and mechanical degree of freedom and are actively pursued for their ability to explore quantum mechanical phenomena of macroscopic objects. Many of these investigations require preparation of the mechanical system in or close to its quantum ground state. Remarkable progress in ground state cooling has been achieved for trapped ions and atoms confined in optical lattices. Imperative to this progress has been the technique of resolved sideband cooling, which allows overcoming the inherent temperature limit of Doppler cooling and necessitates a harmonic trapping frequency which exceeds the atomic species' transition rate. The recent advent of cavity back-action cooling of mechanical oscillators by radiation pressure has followed a similar path with Doppler-type cooling being demonstrated, but lacking inherently the ability to attain ground state cooling as recently predicted. Here we demonstrate for the first time resolved sideband cooling of a mechanical oscillator. By pumping the first lower sideband of an optical microcavity, whose decay rate is more than twenty times smaller than the eigen-frequency of the associated mechanical oscillator, cooling rates above 1.5 MHz are attained. Direct spectroscopy of the motional sidebands reveals 40-fold suppression of motional increasing processes, which could enable reaching phonon occupancies well below unity (<0.03). Elemental demonstration of resolved sideband cooling as reported here should find widespread use in opto-mechanical cooling experiments. Apart from ground state cooling, this regime allows realization of motion measurement with an accuracy exceeding the standard quantum limit.Comment: 13 pages, 5 figure

Gene expression profiles of 4‐hydroxy‐N‐desmethyl‐tamoxifen (endoxifen)‐ and 4‐hydroxy‐tamoxifen (4OHTAM)‐treated human breast cancer cells determined by CDNA microarray analysis

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109798/1/cptclpt2004192.pd

Dynamics of on-line Hebbian learning with structurally unrealizable restricted training sets

We present an exact solution for the dynamics of on-line Hebbian learning in neural networks, with restricted and unrealizable training sets. In contrast to other studies on learning with restricted training sets, unrealizability is here caused by structural mismatch, rather than data noise: the teacher machine is a perceptron with a reversed wedge-type transfer function, while the student machine is a perceptron with a sigmoidal transfer function. We calculate the glassy dynamics of the macroscopic performance measures, training error and generalization error, and the (non-Gaussian) student field distribution. Our results, which find excellent confirmation in numerical simulations, provide a new benchmark test for general formalisms with which to study unrealizable learning processes with restricted training sets.Comment: 7 pages including 3 figures, using IOP latex2e preprint class fil

Using ultra-low frequency waves and their characteristics to diagnose key physics of substorm onset

Substorm onset is marked in the ionosphere by the sudden brightening of an existing auroral arc or the creation of a new auroral arc. Also present is the formation of auroral beads, proposed to play a key role in the detonation of the substorm, as well as the development of the large-scale substorm current wedge (SCW ), invoked to carry the current diversion. Both these phenomena, auroral beads and the SCW, have been intimately related to ultra-low frequency (ULF) waves of specific frequencies as observed by ground-based magnetometers. We present a case study of the absolute and relative timing of Pi1 and Pi2 ULF wave bands with regard to a small substorm expansion phase onset. We find that there is both a location and frequency dependence for the onset of ULF waves. A clear epicentre is observed in specific wave frequencies concurrent with the brightening of the substorm onset arc and the presence of “auroral beads”. At higher and lower wave frequencies, different epicentre patterns are revealed, which we conclude demonstrate different characteristics of the onset process; at higher frequencies, this epicentre may demonstrate phase mixing, and at intermediate and lower frequencies these epicentres are characteristic of auroral beads and cold plasma approximation of the “Tamao travel time” from near-earth neutral line reconnection and formation of the SCW

Association between remnant lipoprotein cholesterol levels and non-alcoholic fatty liver disease in adolescents

Background & Aims: Remnant lipoprotein cholesterol (RLP-C) is an atherogenic lipid profile associated with non-alcoholic fatty liver disease (NAFLD) and cardiovascular disease (CVD). With increased rates of CVD seen in adults with NAFLD, RLP-C has the potential to identify individuals with NAFLD who are at increased risk of CVD. This study examined in adolescents sex-different associations among RLP-C, NAFLD, and cardiometabolic risk factors, and whether RLP-C is associated with NAFLD beyond traditional cardiometabolic risk factors. Methods: Adolescents in the Raine Study had anthropometry, clinical, biochemistry and arterial stiffness measurements recorded at 17 years of age. Fatty liver, subcutaneous and visceral adipose thickness were assessed using abdominal ultrasound. Relationships among RLP-C, NAFLD, liver biochemistry, insulin resistance, adipokines, adiposity and arterial stiffness were assessed. Results: NAFLD was diagnosed in 15.1% (19.6% females and 10.7% males) of adolescents. Increasing RLP-C levels were associated with increasing severity of hepatic steatosis and metabolic syndrome. Adolescents with NAFLD and serum RLP-C levels in the highest quartile compared with the lowest quartile, had higher serum leptin, homeostatic model assessment of insulin resistance (HOMA-IR), high-sensitivity C-reactive protein, low-density-lipoprotein cholesterol, triglycerides, BMI, subcutaneous and visceral adipose thickness, systolic blood pressure and arterial stiffness, but lower adiponectin and high-density-lipoprotein cholesterol. Using multivariable logistic regression, RLP-C in the lowest quartile compared with the highest quartile was associated with 85% lower odds of NAFLD in males and 55% in females, after adjusting for waist circumference, leptin, ALT, adiponectin and HOMA-IR. Conclusions: There is an association between RLP-C and NAFLD beyond traditional risk factors of adiposity and insulin resistance in adolescents. Although raised serum RLP-C levels were associated with the severity of hepatic steatosis and markers of cardiometabolic risk, lower serum RLP-C might reflect reduced cardiovascular risk. Lay summary: Remnant lipoprotein cholesterol (RLP-C) is a part of the blood cholesterol that is linked with heart disease and non-alcoholic fatty liver disease (NAFLD) in adults. In the Raine Study, teenagers with high RLP-C levels had more severe fat accumulation in their liver. Thus, RLP-C might be the hidden link between NAFLD and future risk of heart disease