Background: A 5 Ci 241Am-Be radio isotopic neutron source-based prompt gamma neutron activation analysis (PGNAA) setup was designed for estimation of minimum detectable concentration (MDC) of elements in aqueous solutions. Materials and Methods: Performance variables related to PGNAA setup (source to sample distance, sample to detector distance and volume of water) were optimized experimentally...

Let P be a set of n points in the plane. For a line L ⊂ R, we can project the points P orthogonally onto L, which we denote by πL(P ). Imagine that the line L is a graduated line, that is, a line decomposed into line segments (cells) of length one. For a cell c ⊂ L, let Pop(P, c) be the population of the cell c after the projection, that is Pop(P, c) = |{p ∈ P |πL(p) ∈ c}|. For a graduated line...

We introduce a formal model for geographic social networks, and introduce the notion of rank-based friendship, in which the probability that a person v is a friend of a person u is inversely proportional to the number of people w who live closer to u than v does. We then prove our main theorem, showing that rank-based friendship is a sufficient explanation of the navigability of any geographic ...

We introduce a formal model for geographic social networks, and introduce the notion of rank-based friendship, in which the probability that a person v is a friend of a person u is inversely proportional to the number of people w who live closer to u than v does. We then prove our main theorem, showing that rank-based friendship is a sufficient explanation of the navigability of any geographic ...

Prompt membrane permeabilization is a requisite for liposomes designed for local stimuli-induced intravascular release of therapeutic payloads. Incorporation of a small amount (i.e., 5 molar percent) of an unsaturated phospholipid, such as dioleoylphosphatidylcholine (DOPC), accelerates near infrared (NIR) light-triggered doxorubicin release in porphyrin-phospholipid (PoP) liposomes by an order...

This study evaluated the bonding characteristics to ground and unground enamel obtained with different strategies. For this purpose, 24 sound third-molars were bisected mesiodistally to obtain tooth halves. A flat enamel area was delimited in the tooth sections, which were randomly distributed into 8 groups (n=6), according to the enamel condition (ground and unground) and adhesive system (Adpe...

A wet-oxidation method is presented for determining simultaneously particulate organic carbon (POC), particulate organic nitrogen (PON) and particulate organic phosphorus (POP) collected on filters. Conversion of POC, PON and POP to inorganic products, carbon dioxide, nitrate+nitrite and soluble reactive phosphate respectively, is performed by a persulfate wet-oxidation in slight alkaline condi...

background and aims. the aim of this study was to evaluate the effect of dilution and curing methods of an etch-and-rinse adhesive and a self-etching primer from the same manufacturer at early exposure time on cytotoxicity of primary hu-man gingival fibroblasts. materials and methods. primary human gingival fibroblasts were exposed to different dilutions of adper single bond (asb) and adper pro...

adequate bond strength between glass ionomer cements and composite resin is necessary for the success of the sandwich technique.this study assessed the micro-shear bond strength of composite resin to glass-ionomer cements (gic) using self-etch adhesives with different ph values.one hundred specimens (6×4×2 mm) were made using fuji ii and fuji ii lc gics and treated with different adhesives as f...

A learner who can solve a problem cannot always understand the problem adequately. In order to deeply understand a problem, it is necessary that he/she poses various problems which can be solved by the “solution method” of the problem. Moreover, after he/she poses problems, it is necessary that he/she considers and indicates differences between the problems posed by him/her, too. So, we develop...