Non-linear dose response relationships pose statistical challenges for their discovery. Even when an initial linear approximation is followed by other approaches, the results may be misleading and, possibly, preclude altogether the discovery of the nonlinear relationship under investigation. We review a variety of straightforward statistical approaches for detecting nonlinear relationships and ...

Children's ability to place fractions on a number line strongly correlates with math achievement. But does the number line play a causal role in fraction learning or does it simply index more advanced fraction knowledge? The number line may be a particularly effective representation for fraction learning because its properties align with the desired mental representation and take advantage of p...

dactylogyrus spp. are monogenean worms found mostly as ectoparasites on the gills of several fish species, including carp and goldfish. these parasites are commonly detected by microscopic analysis of the gill lamellae, but this is time-consuming and technically difficult. in contrast to this conventional method, molecular techniques provide specific, sensitive and safe detection of parasites. ...

The mechanism by which protective immunity to Plasmodium is lost in the absence of continued exposure to this parasite has yet to be fully elucidated. It has been recently shown that IFN-γ produced during human and murine acute malaria primes the immune response to TLR agonists. In this study, we investigated whether IFN-γ-induced priming is important to maintain long-term protective immunity a...

conclusions according to the results of the present study, the prevalence of some infections with intestinal parasites is high in the hamadan city. considering that most of the parasites are nonpathogenic, pathogenic ones have been reduced generally in comparison to the previous reports. nevertheless, the existence of taenia species and h. nana could not be ignored. results among 228 samples, 8...

hydatid disease commonly involves liver but in rare cases, it can involve cardiac structures. a 75-yr-old farmer from parsabad-moghan, northwestern iran was presented to the emergency room of tehran imam khomeini hospital, tehran, iran with dyspnea and without chest pain in 2014. a lesion compatible with hydatid cyst was found in echocardiography and confirmed by serology and mri. surgical trea...

In most natural infections or after recovery, small numbers of Leishmania parasites remain indefinitely in the host. Persistent parasites play a vital role in protective immunity against disease pathology upon reinfection through the process of concomitant immunity, as well as in transmission and reactivation, yet are poorly understood. A key question is whether persistent parasites undergo rep...

We examined the relationship between the numbers of brain-encysting trematodes (Ornithodiplostomum ptychocheilus) and the magnitude of altered behaviors in fathead minnows (Pimephales promelas). Because cysts develop within a brain region that integrates visual stimuli with motor response. we evaluated the standard optomotor response (OMR). Monitoring this task involved recording the time minno...

Previous studies have indicated that Il21r (-/-) mice chronically infected with Toxoplasma gondii display a defect in serum IgG; however, the basis for this antibody defect was not defined and questions remain about the role of IL-21 in promoting the production of IL-10, which is required to limit infection-induced pathology during toxoplasmosis. Therefore, Il21 (-/-) mice were challenged with ...