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Rumor, misinformation and oral contraceptive use in Egypt.

Rumor and misinformation about oral contraceptives continue to prevail in much of Egypt. This study tests the hypothesis that rumor involvement can have a negative and independent impact on pill usage by focusing on a common misbelief that the pill causes 'weakness'. The data comes from a 1981-1982 national self-weighted sample survey of 3283 currently married men and women dealing with family planning and mass media behaviors. The analyses confirm that rumor involvement decreases the probability of current or future pill use by previous users and by those who have never used it. Correct knowledge about the pill is shown to enhance pill usage as do other determinants such as social support for birth control and the desire for no more children. The importance of providing strong contraceptive education programs giving deeper consideration to contraceptive and related health beliefs in delivering fertility regulation services is highlighted.

Adult↗

Wittgenstein running: neural mechanisms of collective intentionality and we-mode.

In this paper we discuss the problem of the neural conditions of shared attitudes and intentions: which neural mechanisms underlie "we-mode" processes or serve as precursors to such processes? Neurophysiological and neuropsychological evidence suggests that in different areas of the brain neural representations are shared by several individuals. This situation, on the one hand, creates a potential problem for correct attribution. On the other hand, it may provide the conditions for shared attitudes and intentions.

Brain↗

Urinary metabolites of di-n-octyl phthalate in rats.

Di-n-octyl phthalate (DnOP) is a plasticizer used in polyvinyl chloride plastics, cellulose esters, and polystyrene resins. The metabolism of DnOP results in the hydrolysis of one ester linkage to produce mono-n-octyl phthalate (MnOP), which subsequently metabolizes to form oxidative metabolites. We investigated the toxicokinetics of DnOP in adult female Sprague-Dawley rats by monitoring the excretion of DnOP metabolites in urine after oral administration of DnOP (300 mg/kg). By using authentic standards, the presence of urinary phthalic acid (PA), MnOP, and the major DnOP metabolite, mono-(3-carboxypropyl) phthalate (MCPP) was clearly established. Furthermore, we identified five additional urinary DnOP oxidative metabolites based on their chromatographic behavior and mass spectrometric fragmentation pattern. These DnOP oxidative metabolites, are postulated to be mono-carboxymethyl phthalate (MCMP), mono-(5-carboxy-n-pentyl) phthalate (MCPeP), mono-(7-carboxy-n-heptyl) phthalate (MCHpP), and isomers of mono-hydroxy-n-octyl phthalate (MHOP) (e.g., mono-(7-hydroxy-n-octyl) phthalate) and of mono-oxo-n-octyl phthalate (MOOP) (e.g., mono-(7-oxo-n-octyl) phthalate). The urinary excretion of DnOP metabolites followed a biphasic excretion pattern. The metabolite levels decreased significantly after the first day of DnOP administration although MCPP, MCHpP, MHOP, and MOOP were detectable after 4 days. We also studied the in vitro metabolism of DnOP and MnOP by rat liver microsomes. DnOP produced MnOP, MHOP, and PA in vitro whereas, MnOP produced MHOP and PA in vitro at detectable levels.

Administration, Oral↗

Urinary oxidative metabolites of di(2-ethylhexyl) phthalate in humans.

Di(2-ethylhexyl) phthalate (DEHP) is added to polyvinyl chloride (PVC) plastics used widely in medical devices and toys to impart flexibility and durability. DEHP produces reproductive and development toxicities in rodents. Initial metabolism of DEHP in animals and humans results in mono(2-ethylhexyl) phthalate (MEHP), which subsequently metabolizes to a wide range of oxidative metabolites before being excreted in urine and feces. We investigated the metabolism of DEHP in humans by identifying urinary oxidative metabolites of DEHP from individuals with urinary MEHP concentrations about 100 times higher than the median concentration in the general US population. In addition to the previously identified DEHP metabolites MEHP, mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), and mono(2-carboxymethylhexyl) phthalate (MCMHP), we also identified for the first time in humans three additional oxidative metabolites, mono(2-ethyl-3-carboxypropyl) phthalate (MECPrP), mono(2-ethyl-4-carboxybutyl) phthalate (MECBP), and mono(2-(1-oxoethyl)hexyl) phthalate (MOEHP) based on their chromatographic behavior and mass spectrometric fragmentation patterns. We also tentatively identified metabolites with two functional groups in the side alkyl chain as isomers of mono(2-hydroxyethyl-4-carboxybutyl) phthalate (MHECBP), mono(2-ethyl-4-oxo-5-carboxypentyl) phthalate (MEOCPP), and mono(2-ethyl-4-hydroxy-5-carboxypentyl) phthalate (MEHCPP). We report the presence of urinary DEHP metabolites in humans that have fewer than eight carbons in the alkyl chain. These metabolites were previously identified in rodents. Although quantitative information is not available, our findings suggest that, despite potential differences among species, the oxidative metabolism of DEHP in humans and rodents results in similar urinary metabolic products.

Adult↗

Cooperation of solid granule and solvent as porogenic agents. Novel porogenic mode of biporous media for protein chromatography.

A novel porogenic mode, cooperation of solid granule and solvent, has been introduced to prepare a biporous medium for protein chromatography. The matrix, a ternary copolymer of glycidyl methacrylate, triallylisocyanurate and divinylbenzene, was produced by a simple in situ polymerization with granules of sodium sulfate and cyclohexanol and dodecanol as porogenic agents. Functionalized with diethylamine, the resin (denoted as Resin C) was used as an anion exchanger. The pore structure, specific surface area and chromatographic properties of Resin C were determined and compared with those of the resin with only the solvents as porogen (Resin A) and the resin with only the salt granules as porogen (Resin B). The results indicated that Resin C contained regions of micropores with a maximum at approximately 55 nm and regions of macropores with a distinct maximum near 340 nm, which swelled to about 1 microm in aqueous solution. Compared with Resins A and B, the biporous medium Resin C simultaneously possessed a high specific surface area of 37.2 m2/g and a low back-pressure at mobile phase flow velocity up to 720 cm/h. The result of dynamic porosity showed that mobile phase was able to convectively flow through the macropores in Resin C. The dynamic adsorption capacity of Resin C for bovine serum albumin was as high as 57.0 mg/ml column volume (95.0 mg/g wet resin), basically identical to its static capacity, while that of Resin A was only 1.95 mg/ml column volume (3.12 mg/g wet resin), about 3% that of its static capacity. In addition, the column efficiency of Resin C was comparable to that of Resin B, but much higher than that of Resin A, indicating that the mass transfer behavior of proteins in the column was greatly improved by convective flow through the macropores.

Adsorption↗

"Mobbing".

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Civil Disorders↗

Passive dissolution of hydrogen gas into groundwater using hollow-fiber membranes.

A new hollow-fiber membrane remediation system has recently been developed to passively supply groundwater with dissolved hydrogen (H2) to stimulate the biodegradation of chlorinated solvents. Understanding the mass transfer behavior of membranes under conditions of creeping flow is critical for the design of such systems. Therefore, the objectives of this research were to evaluate the gas transfer behavior of hollow-fiber membranes under conditions typical of groundwater flow and to assess the effect of membrane configuration on gas transfer performance. Membrane gas transfer was evaluated using laboratory-scale glass columns operated at low flow velocities (8.6-12,973 cm/d). H2 was supplied to the inside of the membrane fibers while water flowed on the outside and normal to the fibers (i.e. cross-flow). Membrane configuration (single fiber and fabric) and membrane spacing for the fabric modules did not affect gas transfer performance. Therefore, the results from all of the experiments were combined to obtain the following dimensionless Sherwood number (Sh) correlation expressed as a function of Reynolds number (Re) and Schmidt number (Sc): Sh = 0.824Re(0.39)Sc(0.33) (0.0004<Re<0.6). This correlation is useful for predicting the rate of transfer of any gas from clean membranes to flowing water at low Re. This correlation provides a basis for estimating the membrane surface area requirements for groundwater remediation as illustrated by a simple example.

Biodegradation, Environmental↗