Knowledge and attitudes toward breast-feeding: differences among dietitians, nurses, and physicians working with WIC clients

We assessed the knowledge of and attitude toward breast-feeding of dietitians, nurses, and physicians who work with individuals in the Alabama Special Supplemental Food Program for Women, Infants, and Children. On a scale of 0 to 100, dietitians expressed stronger interest in lactation (78.6) and exhibited greater knowledge (79.6) of the questions asked than nurses (74.5 and 73.0, respectively). Attitude and knowledge scores of physicians (70.2 and 75.5, respectively) were not statistically different from those of dietitians or nurses. Respondents disagreed greatly about the relationship of breast-feeding to weight loss and the appropriateness of oral contraceptives during breast-feeding 6 weeks postpartum. Professionals were more knowledgeable about benefits to infants than about maternal concerns. Results of this study suggest that professional breast-feeding education programs should address maternal concerns such as weight loss, contraception, and mastitis as well as benefits to the infant.     

Techniques for visualization of cavern boundaries in opaque industrial mixing systems

In the agitation of complex fluids, the avoidance of caverns is essential for successful blending. Electrical resistance tomography (ERT) and positron emission projection imaging, which can both image within opaque fluids, have been assessed for visualization of cavern boundaries. A vessel of diameter, T = 154 mm, equipped with a single 57 mm diameter six bladed 45° down pumping pitched blade disc turbine formed the test system. The fluid used was aqueous solution of carbopol 940. Both techniques were used to detect and image caverns at Re from 20–86.6 and compared with optical images. Reasonable agreement on the maximum cavern heights and widths were obtained, with the taller and narrower caverns obtained via 3D ERT measurements being attributed to artifacts of the method and interactions between the polymer and tracer. Caverns were also detectable using a robust linear ERT array, which has potential for use within industrial systems. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

Stereological estimation of Weibel-Palade bodies in the retinal vasculature of normal and diabetic dogs

The absolute volume of Weibel-Palade (WP) bodies, the storage organelles of von Willebrand factor (vWF), was estimated by a stereological method in a known volume of central retina from normal and 5-year diabetic dogs. The results showed that the volume of WP bodies present in the endothelium of the retinal vasculature varies with blood vessel type and in diabetes. In both diabetic and normal dogs the endothelium of the retinal veins contained a higher volume of WP bodies than that of the retinal arteries. In dogs which had been diabetic for a duration of 5 years the volume of WP bodies present in the endothelium of retinal veins was significantly greater than in the endothelium of veins from the control animals. However, there was no significant difference in the volume of WP bodies present in the endothelium of retinal arteries or capillaries between the two groups of animals.     

2DRMP: A suite of two-dimensional R-matrix propagation codes

The R-matrix method has proved to be a remarkably stable, robust and efficient technique for solving the close-coupling equations that arise in electron and photon collisions with atoms, ions and molecules. During the last thirty-four years a series of related R-matrix program packages have been published periodically in CPC. These packages are primarily concerned with low-energy scattering where the incident energy is insufficient to ionise the target. In this paper we describe 2DRMP, a suite of two-dimensional R-matrix propagation programs aimed at creating virtual experiments on high performance and grid architectures to enable the study of electron scattering from H-like atoms and ions at intermediate energies.

Program summary

Program title: 2DRMPCatalogue identifier: AEEA_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEEA_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 196 717No. of bytes in distributed program, including test data, etc.: 3 819 727Distribution format: tar.gzProgramming language: Fortran 95, MPIComputer: Tested on CRAY XT4 [1]; IBM eServer 575 [2]; Itanium II cluster [3]Operating system: Tested on UNICOS/lc [1]; IBM AIX [2]; Red Hat Linux Enterprise AS [3]Has the code been vectorised or parallelised?: Yes. 16 cores were used for small test runClassification: 2.4External routines: BLAS, LAPACK, PBLAS, ScaLAPACKSubprograms used: ADAZ_v1_1Nature of problem: 2DRMP is a suite of programs aimed at creating virtual experiments on high performance architectures to enable the study of electron scattering from H-like atoms and ions at intermediate energies.Solution method: Two-dimensional R-matrix propagation theory. The (r₁,r₂) space of the internal region is subdivided into a number of subregions. Local R-matrices are constructed within each subregion and used to propagate a global R-matrix, ℜ, across the internal region. On the boundary of the internal region ℜ is transformed onto the IERM target state basis. Thus, the two-dimensional R-matrix propagation technique transforms an intractable problem into a series of tractable problems enabling the internal region to be extended far beyond that which is possible with the standard one-sector codes. A distinctive feature of the method is that both electrons are treated identically and the R-matrix basis states are constructed to allow for both electrons to be in the continuum. The subregion size is flexible and can be adjusted to accommodate the number of cores available.Restrictions: The implementation is currently restricted to electron scattering from H-like atoms and ions.Additional comments: The programs have been designed to operate on serial computers and to exploit the distributed memory parallelism found on tightly coupled high performance clusters and supercomputers. 2DRMP has been systematically and comprehensively documented using ROBODoc [4] which is an API documentation tool that works by extracting specially formatted headers from the program source code and writing them to documentation files.Running time: The wall clock running time for the small test run using 16 cores and performed on [3] is as follows: bp (7 s); rint2 (34 s); newrd (32 s); diag (21 s); amps (11 s); prop (24 s).References:

• [1] 

  HECToR, CRAY XT4 running UNICOS/lc, http://www.hector.ac.uk/, accessed 22 July, 2009.

• [2] 

  HPCx, IBM eServer 575 running IBM AIX, http://www.hpcx.ac.uk/, accessed 22 July, 2009.

• [3] 

  HP Cluster, Itanium II cluster running Red Hat Linux Enterprise AS, Queen s University Belfast, http://www.qub.ac.uk/directorates/InformationServices/Research/HighPerformanceComputing/Services/Hardware/HPResearch/, accessed 22 July, 2009.

• [4] 

  Automating Software Documentation with ROBODoc, http://www.xs4all.nl/~rfsber/Robo/, accessed 22 July, 2009.

     

Instability of pUC19 in Escherichia coli transcription termination factor mutant, rho026

We compared internalization of three radioiodinated octreotide (OCT) somatostatin (SS) analogs-[125I-Tyr3]OCT, [DTPA degrees, 125I-Tyr3]OCT, and [DOTA degrees,125I-Tyr3]OCT-by somatostatin receptor (SSR)-positive mouse AtT20 pituitary tumor cells and human insulinoma cells. The three SS analogs were internalized in a specific, time-dependent manner. Internalization was significantly inhibited by pertussis toxin (100 microg/l) by 38%, 43%, and 31%, and by an inhibitor of receptor-mediated endocytosis (phenyl arsine oxide; 10 microM) by 98%, 94%, and 92%, respectively. Binding affinities of the three radioligands were comparable (0.2, 0.2, and 0.3 nM, respectively). However, [DOTA degrees,125I-Tyr3]OCT was internalized in a five-fold higher amount in comparison with the two other radioligands. A comparably high uptake of [DOTA degrees, 125I-Tyr3]OCT was found in SSR-positive organs (pituitary, pancreas, and adrenals) in vivo in rats (a ten-fold, five-fold, and eight-fold higher uptake 4 hr post injection, respectively, compared with the two other radioligands). This resulted in very high target-background ratios for [DOTA degrees,125I-Tyr3]OCT 4 hr post injection amounting to 274, 566, and 623 in the pituitary, adrenals, and pancreas, respectively. Both in vivo and in vitro there was a rapid dissociation of radioactivity from the SSR-positive cells. Main conclusions are that: 1) coupling of chelating groups like DTPA or DOTA to the SS analog [Tyr3]OCT does not prevent the internalization of OCT after binding to SSRs; 2) [DOTA degrees, 125I-Tyr3]OCT is internalized in a significantly higher amount by AtT20 and human insulinoma cells and in vivo in rats in SSR-positive organs, in comparison with [DTPA degrees,125I-Tyr3]OCT and [125I-Tyr3]OCT; and 3) the very high target-background ratios in vivo make radioiodinated [DOTA degrees,Tyr3]OCT a very suitable ligand for SSR-targeted radioguided surgery of SSR-positive human neuroendocrine tumors.     

Bubble sizes in agitated solvent/reactant mixtures used in heterogeneous catalytic hydrogenation of 2-butyne-1,4-diol

Catalytic hydrogenations reactions are frequently conducted in “dead-end” multiphase stirred reactors with the reactant dissolved either in an alcohol, or in water or a mixture of the two. In such systems, the rate of gas-liquid mass transfer, which depends on bubble size, may well be the overall rate-limiting step. However, a study of bubble sizes across the whole range of solvent compositions from entirely water to entirely organic has not been reported. Here, for the first time, a systematic investigation has been made in a 3 L, closed vessel simulating a “dead-end” reactor containing 1% by volume of air which is dispersed by a Rushton turbine in water, isopropanol (IPA) and mixtures of the two, with and without 2-butyne-1,4-diol simulating a reactant. Mean specific energy dissipation rates, , up to have been used and bubbles size distributions and mean size were measured using a video-microscope-computer technique. In the single component solvents (water, ; IPA, though the interfacial tensions are very different, irregular, relatively large bubbles of similar sizes were observed ( in IPA, and in water) with a wide size distribution. In the mixed aqueous/organic solvents, and especially at the lower concentrations of IPA (1%, 5%, 10%), the bubbles were spherical, much smaller (d₃₂ from 50 to ) with a narrow size distribution. The addition of the reactant (0.2 M 2-butyne-1,4-diol) to the mixed solvents had little effect on the mean size, shape or distribution. However, addition to water (thus producing a mixed aqueous/organic liquid phase) led to small spherical bubbles of narrow size distribution. Neither Weber number nor surface tension was suitable for correlating bubble sizes since σ decreased steadily from pure water to IPA whilst bubble size passed through a minimum at around 5% IPA. For any particular fluid composition, the functionality between d₃₂ and was similar, i.e. . The above observations are explained in terms of the polarisation of bubble surfaces in miscible mixed aqueous/organic liquids caused by preferential directional adsorption at low concentrations of the organic component with its hydrophilic part directed into the aqueous phase and its hydrophobic part into the gas phase. As a result, coalescence is heavily suppressed in the low-concentration miscible alcohol (or diol)/aqueous systems whilst strong coalescence dominates bubble sizes in water and the alcohol and at high concentrations of the latter.     

Interaction versus independence of startle-modification processes in the rat

The absolute bioavailability of quinidine was studied in 11 hospitalized patients. A 400-mg dose of quinidine gluconate was administered to each patient by intravenous infusion and as an oral solution. Drug treatments were separated by a 72-hr period. In 8 patients, peak plasma quinidine concentrations were reached in 65 min after the oral dose; in the remaining 3 subjects, peak concentrations were reached later. From the ratio of the total area under the plasma concentration-time curves (AUCoral/AUCir), the absolute bioavailability of quinidine ranged from 44% to 89% (mean, 72). In 8 patients, the ratio of the total amount of quinidine excreted in the urine in 48 hr (AUinfinity oral/AUinfinity ir) indicated that the extent of quinidine bioavailability varied form 47% to 96% (mean, 73). The predicted bioavailability of quindine due to first-pass effects was 76+/-11%. It is concluded that absorption after the oral solution was rapid and that the reduction of quinidine bioavailability was due to first-pass hepatic drug removal.     

Advanced glycation end products in vitreous: Structural and functional implications for diabetic vitreopathy

PURPOSE: Advanced glycation end products (AGEs) form irreversible cross-links with many macromolecules and have been shown to accumulate in tissues at an accelerated rate in diabetes. In the present study, AGE formation in vitreous was examined in patients of various ages and in patients with diabetes. Ex vivo investigations were performed on bovine vitreous incubated in glucose to determine AGE formation and cross-linking of vitreous collagen. METHODS: By means of an AGE-specific enzyme-linked immunosorbent assay (ELISA), AGE formation was investigated in vitreous samples obtained after pars plana vitrectomy in patients with and without diabetes. In addition, vitreous AGEs were investigated in bovine vitreous collagen after incubation in high glucose, high glucose with aminoguanidine, or normal saline for as long as 8 weeks. AGEs and AGE cross-linking was subsequently determined by quantitative and qualitative assays. RESULTS: There was a significant correlation between AGEs and increasing age in patients without diabetes (r = 0.74). Furthermore, a comparison between age-matched diabetic and nondiabetic vitreous showed a significantly higher level of AGEs in the patients with diabetes (P < 0.005). Collagen purified from bovine vitreous incubated in 0.5 M glucose showed an increase in AGE formation when observed in dot blot analysis, immunogold labeling, and AGE ELISA. Furthermore, there was increased cross-linking of collagen in the glucose-incubated vitreous, when observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and protein separation. This cross-linking was effectively inhibited by coincubation with 10 mM aminoguanidine. CONCLUSIONS: This study suggests that AGEs may form in vitreous with increasing age. This process seems to be accelerated in the presence of diabetes and as a consequence of exposure to high glucose. Advanced glycation and AGE cross-linking of the vitreous collagen network may help to explain the vitreous abnormalities characteristic of diabetes.     

Production and absorption of nitric oxide gas in the nose

Some nitric oxide gas (NO) produced in the sinuses and nasal cavity is absorbed before leaving the nose. To measure production and absorption, we introduced NO at different concentrations into one nostril while sampling the NO leaving the opposite nostril with the soft palate closed. The quantity of NO gas produced in six normal subjects (amount leaving plus the amount absorbed) averaged 352 nl/min and was the same at gas flows ranging from 8 to 347 ml/min and at 10 l/min. An absorption coefficient A was calculated by dividing the amount of NO absorbed by the concentration leaving the nose. A ranged from 17 ml/min at a nasal gas flow of 8 ml/min to an A of 24 ml/min at a nasal gas flow of 347 ml/min. The calculated rates of production and absorption did not change when gas flow rate was increased, suggesting diffusion equilibrium. The amount of uptake of NO in the nasal mucosa can be explained by its solubility coupled with tissue and blood reactivity.     

Heterogeneous oxidation of 2-octanol on 5 wt%Pt–1 wt%Bi/Carbon catalyst

The low activity of 5%Pt–1%Bi/Carbon for the oxidation of 2-octanol at atmospheric pressure and 343 K was investigated. Using solvents such as heptane and p-xylene, it was shown that the reaction rates decrease dramatically shortly after the start of the reaction due to poisoning by product adsorption. Hence this work investigates the effect of using different solvent mixtures on the oxidation reaction of 2-octanol with 5%Pt–1%Bi/Carbon. Mixtures with different volumetric ratios of heptane and dioxane were investigated to find the best composition capable of effectively removing the adsorbed amphiphilic ketone. It is apparent that the reaction rate is correlated with the adsorption coefficient of ketone on the catalyst, such that the maximum reaction rate occurs at the lowest ketone adsorption coefficient, corresponding to a concentration of 16–18%v/v dioxane. A model based on a Langmuir–Hinshelwood mechanism has been successfully fitted to the experimental rates.