Aquaporins enable the passage of a diverse set of solutes besides water. Many novel aquaporin permeants, such as antimonite and arsenite, silicon, ammonia, and hydrogen peroxide, have been described very recently. By the same token, the number of available aquaporin sequences has rapidly increased. Yet, sequence analyses and structure models cannot reliably predict permeability properties. Even...

BACKGROUND A prevailing assumption in neuroimaging studies is that relatively low fMRI signals are due to weak neuronal activation, and, therefore, they are commonly ignored. However, lower fMRI signals may also result from intense activation by highly selective, albeit small, subsets of neurons in the imaged voxel. We report on an approach that could form a basis for resolving this ambiguity i...

In Part I of this work, using a one-dimensional (1D) representation of the two-dimensional (2D) electrostatic and ion concentration fields, we showed that highly selective adhesion can be achieved between two charged surfaces separated by an electrolyte. In Part II of this work, we provide a detailed theoretical justification of our 1D model by solving the electrostatic problem in a 2D configur...

activated charcol phase loaded with 2-propylpiperidine-1-carbodithioate (ppcd) were synthesized based on chemical binding and physical adsorption approaches. the stability of a chemically modified ppcd especially in concentrated hydrochloric acid which was then used as a recycling and pre-concentration reagent for further uses of activated charcol immobilized ppcd. the application of this activ...

The relative contributions of feedforward and recurrent connectivity to the direction-selective responses of cells in layer IVB of primary visual cortex are currently the subject of debate in the neuroscience community. Recently, biophysically detailed simulations have shown that realistic direction-selective responses can be achieved via recurrent cortical interactions between cells with nondi...

Groups of time-courses created from fMRI data by the frequently used correlation analysis are often highly heterogeneous. This heterogeneity is due to the limited selectivity of correlation when trying to match brain time-courses to an externally imposed activation paradigm. Thus, this process unnecessarily generates many type I errors (false positives). Furthermore, as a consequence of the het...

Using econometric models of endogenous sample selection, we examine possible payment bias to Medicare Tax Equity and Fiscal Responsibility Act of 1982 (TEFRA) risk health maintenance organizations (HMOs) in the Twin Cities in 1988. We do not find statistically significant evidence of favorable HMO selection. In fact, the sign of the selection term indicates adverse selection into HMOs. This fin...

Primary visual cortex (V1) provides crucial insights into the selectivity and emergence of specific output features such as orientation tuning. Tuning and selectivity of cortical neurons in mouse visual cortex is not equivocally resolved so far. While many in-vivo experimental studies found inhibitory neurons of all subtypes to be broadly tuned for orientation other studies report inhibitory ne...