bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects on plasma lipids and fatty acid composition of very low fat diets enriched with fish or kangaroo meat
Authors: Sinclair Andrew J. , O'Dea Kerin , Dunstan Graeme , Ireland Paul D. , Niall Maggie
Published: January 2007

The effects of very low fat diets (<7% energy) enriched with different sources of long chain (C20 and C22) polyunsaturated fatty acids (PUFA) on plasma lipid levels and plasma fatty acids (PUFA) on plasma lipid levels and plasma fatty acid composition were studied in 13 healthy volunteers. Three diets provided 500 g/day of tropical Australian fish (rich in arachidonic acid and docosahexaenoic acid), southern Australian fish (rich in docosahexaenoic acid) or kangaroo meat (rich in linoleic and arachidonic acids). The fourth diet was vegetarian, similarly low in fat but containing no 20‐ and 22‐carbon PUFA. Subjects ate their normal or usual diets on weeks 1 and 4 and the very low fat diets in weeks 2 and 3. Weighed food intake records were kept, and weeks 2, 3 and 4 were designed to be isoenergetic with week 1.

Plasma cholesterol levels fell significantly on all diets within one week. There were reductions in both low density (LDL) and high density lipoprotein (HDL) cholesterol levels, with effects on HDL cholesterol being more consistent. There were no consistent or significant effects on total triglyceride levels despite the high carbohydrate content of the diets. On all diets the percentage of linoleic acid fell in the plasma phospholipid and cholesteryl ester fractions, while the percentage of palmitic acid in the phospholipids and cholesteryl esters and palmitoleic acid in the cholesteryl ester fraction rose on all diets. The percentage of arachidonic acid rose in the phospholipid and cholesteryl esters on the two diets that were good sources of this fatty acid (tropical fish and kangaroo meat). The percentage of docosahexaenoic acid also rose on the two diets that were the richest sources of this fatty acid (the fish diets), and the percentage of eicosapentaenoic acid rose in the phospholipid and cholesteryl esters in proportion to the dietary level of this fatty acid (southern fish > kangaroo > tropical fish). The changes in fatty acid composition were almost completely reversed within seven days of returning to the usual higher fat diets.
Lipid metabolism of the yellow clam,Mesodesma mactroides: I. Composition of the lipids
Authors: De Moreno Julia E. A. , Moreno Victor J. , Brenner Rodolfo R.
Published: January 2007

The lipid composition of the yellow clam,Mesodesma mactroides, that lives in the northern beaches of the Buenos Aires province of Argentina was studied. The main nonpolar lipids are triglycerides and alkoxyglycerides. Phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl serine are the main phospholipids. The predominant fatty acids are 16∶0, 16∶1ω7, 18∶0, 18∶1ω9, 20∶5ω3, and 22∶6ω3. The are mainly provided by the clam's food and stored in the hepatopancreas. The content of polyunsaturated acids increases in summer together with an increase in nonpolar lipids and is correlative with an increase in phytoplankton in the sea water. Sexual maturity modifies the lipid composition of gametes.
Fluorescent product formation and changes in structure of DNA reacted with peroxidizing arachidonic acid
Authors: Reiss U. , Al Tappel L.
Published: January 2007

Calf thymus DNA was reacted with peroxidizing arachidonic acid at 37 C for 76 hr. Fluorescent DNA products increased with reaction time. These products had characteristic fluorescence spectra with maximum excitation at 315 nm and maximum fluorescence at 420 nm. Structural changes occurred in the DNA reacted with peroxidizing arachidonic acid, as observed by decreased melting point, decreased hyperchromicity, partial resistance to hydrolysis by deoxyribonuclease and by decreased template activity for rat liver RNA polymerase.
Fluorescent products of phospholipids during lipid peroxidation
Authors: Bidlack W. R. , Tappel A. L.
Published: January 2007

During peroxidation, phosphatidyl ethanolamine and phosphatidyl serine formed fluorescent chromophores with maximum emission at 435 nm and maximum excitation at 365 nm. The development of fluorescence was related to formation of thiobarbituric acid reactive substance during lipid peroxidation. This relationship was studied by reacting dipalmityl phosphatidyl ethanolamine with the oxidation products of the methyl esters of arachidonic, linolenic and linoleic fatty acids. Reaction parameters affecting the development of lipid‐extractable fluorescent chromophores are: the production of peroxidation products, especially malonaldehyde, from autoxidation of polyunsaturated fatty acids; the length of time these products react; and the availability of reactive amino groups on the phospholipids.
Nature of fecal sterols and intestinal bacterial flora
Authors: Martin W. J. , Ravi Subbiah M. T. , Kottke B. A. , Birk C. C. , Naylor M. C.
Published: January 2007

Sterol excretion in the spontaneously atherosclerosis‐susceptible White Carneau (WC) pigeon, the Silver King (SK) pigeon and the Show Racer (SR) pigeon was studied by thin layer chromatography (TLC), argentation TLC and gas liquid chromatography. Unlike man and the chicken, these pigeons excreted no coprostanol or coprostanone derivatives of sterols. Moreover incubation of14C‐labeled cholesterol with pigeon feces indicated that, also unlike man and the chicken, these pigeons are unable to convert it to coprostanol. Bacteriologic examination revealed the absence of gram‐negative anaerobic flora and of members of the genusBifidobacterium in both the WC and SR pigeons. On the other hand, one of the two SK pigeons examined showed evidence of the presence of bothBacteroids fragilis andB. bifidum in the upper intestinal tract. Although no qualitative experiments were performed, no unusual characteristics of the aerobic flora were noted in these pigeons. In addition, analysis of human stool specimens indicated a “normal” bowel flora. The flora of the intestinal tract of the chicken is similar to that of the human. Because of this similarity, it appears that differences in environment (living conditions, diets) between the human and the chicken are of little consequence. The results obtained in this study suggest the possibility that the anaerobic gram‐negative flora and sponsible, at least in part, for the chemical conversion of cholesterol to coprostanol.
Intracellular route and mechanism of action of ERB‐hRNase, a human anti‐ErbB2 anticancer immunoagent
Authors: De Lorenzo Claudia , Di Malta Chiara , Calì Gaetano , Troise Fulvia , Nitsch Lucio , D’Alessio Giuseppe
Published: January 2007

Human anti‐ErbB2 immunoRNase with Erbicin fused to HP‐RNase (ERB‐hRNase) is a fully human immunoRNase made up of human pancreatic RNase fused to a human anti‐ErbB2 scFv. It binds selectively with high affinity to ErbB2‐positive cells, and specifically inhibits their proliferation, in vitro and in vivo. An investigation of its mechanism of action and its intracellular destination has revealed that ERB‐hRNase depends on its RNase activity for cytotoxic action; it reaches the cytosol directly from the endosomal compartment; it is inhibited by the cytosolic RNase inhibitor (cRI), but the levels that ERB‐hRNase reaches in the cytosol neutralize cRI, thus inducing cell death by apoptosis.
Predictability of wheat growth and yield in light-limited conditions
Authors: BEED F. D. , PAVELEY N. D. , SYLVESTER-BRADLEY R.
Published: January 2007

In seeking better predictions of grain yield under light-limited conditions, shading was applied to field-grown winter wheat cv. Slejpner during each of five consecutive phases (canopy expansion, ear expansion, pre-flowering, grain expansion and grain filling). Absolute measures were taken of solar radiation and its effects on growth in three seasons, at a site where water and nutrient supplies were not limiting. Replicate mobile shades automatically occluded 0·80 of incident light when mean total solar radiation exceeded 250 J/m2 per s. Mean effects over seasons of shading on incident total solar radiation were −296, −139, −78, −157 and −357 MJ/m2 for the five phases respectively, and corresponding effects on shoot dry weight were −236, −184, −58, −122 and −105 g/m2. Estimated efficiency of radiation use after flowering was 1·2 g/MJ unshaded, tending to increase with shading. Shading in all phases reduced grain dry matter yield: mean effects over seasons were −106, −64, −61, −93 and −281 g/m2 for the five consecutive shading periods. Shading from GS31–39 increased mean maximum area of the two top leaves from 2700 to 3100 mm2 per leaf but, with fewer stems, canopy size remained unaffected. This and the next shading, from GS39–55, reduced specific leaf weight from 42 g/m2 by 4 and 3 g/m2 respectively, but effects on shoot dry weight were largely due to stem and ear. By flowering, stem weights, and especially their reserves of water-soluble carbohydrates, had partially recovered. Effects on yield of shading from GS31–39 were explained by a reduction in grains/m2 of 3070 from 26109. Shading from GS39–55 reduced grains/m2 by 4211 due to fewer grains per ear, whilst mean weight per grain increased in compensation. Shading from GS55–61 decreased grains/ear by 2·5. Shading from GS61–71 decreased ear growth and reduced stem weight, and at harvest resulted in 4·3 less grains/ear. Effects of the final shading from GS71–87 were fully explained by a reduction in mean dry weight/grain of 10·3 mg. Except for shading from GS71–87, source- and sink-based explanations of grain yield both proved feasible, within the precision of the measurements. Constraints to accurate comparison of source- and sink-based approaches are identified, and the implications for yield forecasting are discussed.
Three-dimensional transverse instabilities in detached boundary layers
Authors: GALLAIRE FRANÇOIS , MARQUILLIE MATTHIEU , EHRENSTEIN UWE
Published: January 2007

A direct numerical simulation of the incompressible Navier–Stokes equations of the flow over a bump shows a stationary longitudinal instability at a Reynolds number of Re = 400. A three-dimensional global mode linear analysis is used to interpret these results and shows that the most unstable eigenmode is steady and localized in the recirculation bubble, with spanwise wavelength of approximately ten bump heights. An inviscid geometrical optics analysis along closed streamlines is then proposed and modified to account for viscous effects. This motivates a final discussion regarding the physical origin of the observed instability.
Bluff bodies in deep turbulent boundary layers: Reynolds-number issues
Authors: LIM HEE CHANG , CASTRO IAN P. , HOXEY ROGER P.
Published: January 2007

It is generally assumed that flows around wall-mounted sharp-edged bluff bodies submerged in thick turbulent boundary layers are essentially independent of the Reynolds number Re, provided that this exceeds some (2–3) × 104. (Re is based on the body height and upstream velocity at that height.) This is a particularization of the general principle of Reynolds-number similarity and it has important implications, most notably that it allows model scale testing in wind tunnels of, for example, atmospheric flows around buildings. A significant part of the literature on wind engineering thus describes work which implicitly rests on the validity of this assumption. This paper presents new wind-tunnel data obtained in the ‘classical’ case of thick fully turbulent boundary-layer flow over a surface-mounted cube, covering an Re range of well over an order of magnitude (that is, a factor of 22). The results are also compared with new field data, providing a further order of magnitude increase in Re. It is demonstrated that if on the one hand the flow around the obstacle does not contain strong concentrated-vortex motions (like the delta-wing-type motions present for a cube oriented at 45° to the oncoming flow), Re effects only appear on fluctuating quantities such as the r.m.s. fluctuating surface pressures. If, on the other hand, the flow is characterized by the presence of such vortex motions, Re effects are significant even on mean-flow quantities such as the mean surface pressures or the mean velocities near the surfaces. It is thus concluded that although, in certain circumstances and for some quantities, the Reynolds-number-independency assumption is valid, there are other important quantities and circumstances for which it is not.
Coherent structure in a turbulent jet via a vector implementation of the proper orthogonal decomposition
Authors: IQBAL M. O. , THOMAS F. O.
Published: January 2007

The coherent structure in the near-field of an axisymmetric turbulent jet at a Reynolds number of 3.8 × 105 and Mach number of 0.3 is experimentally characterized by a vector implementation of the proper orthogonal decomposition (POD). The POD eigenfunctions and associated eigenvalues are extracted at several selected streamwise locations in the initial region. The focus on the near-field is motivated by its importance in numerous technical applications. Results show a rapid energy convergence with POD mode number. Examination of the relative energy contained in the combined azimuthal and radial components of the POD modes reveals that it is comparable to that in the streamwise component. The streamwise evolution of the eigenvalue spectra is characterized by a remarkable variation in the azimuthal mode number energy distribution, leading to the dominance of azimuthal mode m = 1 beyond the end of the jet core. In contrast, a scalar implementation using only the streamwise component shows the dominance of mode m = 2 which is consistent with previous scalar implementations of the POD. For a given azimuthal mode number, the eigenvalue spectra exhibit a broad peak which occurs at a constant value of Strouhal number based on local shear layer momentum thickness and local jet maximum velocity. The phase information required for a local reconstruction of the jet structure is obtained by projecting the POD eigenmodes onto instantaneous realizations of the flow at fixed streamwise locations. The instantaneous realizations are obtained by utilizing cross-stream arrays of multi-sensor probes in conjunction with linear stochastic estimation (LSE). Results clearly show the local dynamic behaviour of each component of the jet structure.
Drag and lift forces on bubbles in a rotating flow
Authors: VAN NIEROP ERNST A. , LUTHER STEFAN , BLUEMINK JOHANNA J. , MAGNAUDET JACQUES , PROSPERETTI ANDREA , LOHSE DETLEF
Published: January 2007

The motion of small air bubbles in a horizontal solid-body rotating flow is investigated experimentally. Bubbles with a typical radius of 1 mm are released in a liquid-filled horizontally rotating cylinder. We measure the transient motion of the bubbles in solid-body rotation and their final equilibrium position from which we compute drag and lift coefficients for a wide range of dimensionless shear rates 0.1<Sr<2 (Sr is the velocity difference over one bubble diameter divided by the slip velocity of the bubble) and Reynolds numbers 0.01<Re<500 (Re is based on the slip velocity and bubble diameter). For large Sr, we find that the drag force is increased by the shear rate. The lift force shows strong dependence on viscous effects. In particular, for Re<5, we measure negative lift forces, in line with theoretical predictions.
Their eyes were watching God: African-American topical songs on the 1928 Florida hurricanes and floods
Authors: MONGE LUIGI
Published: January 2007

This study focuses on the five known African-American topical songs dealing with the two hurricanes and ensuing floods that took place in Florida in the summer of 1928. The first is a commercially recorded blues song and the others are unreleased Library of Congress sacred recordings, which are transcribed and analysed here for the first time.
Determining What is Important in a Good Formulation
Authors: Flitcroft Alyson , James Ian Andrew , Freeston Mark , Wood-Mitchell Amy
Published: January 2007

Research suggests that there is low inter-rater reliability between therapists when asked to formulate the same case and that there may be discrepancies in what is considered an essential part of a formulation. The present study aimed to explore the diversity of therapists' viewpoints regarding the purpose and essential features of a cognitive-behavioural therapy (CBT) case formulation of depression. A Q-sort methodology was used in order to render these beliefs operational. Seven experienced CBT therapists participated in the construction of 86 statements, capturing concepts considered relevant to a CBT formulation of depression. This Q-sort was then administered to 23 therapists, who rated these statements in terms of their importance using a Q-sort procedure. Three factors emerged, suggesting three dominant opinions as to the importance of features of a formulation. A “state” CBT factor, focusing on the “here and now”, accounted for most variance; followed by a second factor emphasizing “function and process” and a third factor emphasizing “trait” components. Whilst there was some agreement between what was considered to be least important in a formulation, the emergence of three distinct viewpoints suggests a lack of complete consensus amongst the therapists.
Modeling of Purification Operations in Biotechnology: Enabling Process Development, Optimization, and Scale‐Up
Authors: Velayudhan Ajoy , Menon Manoj K.
Published: January 2007

Process modeling involves the use of a set of mathematical equations to represent key physical phenomena involved in the process. An appropriately validated model can be used to predict process behavior with limited experimental data, identify critical ranges for process variables, and guide further process development. Although process modeling is extensively used in the chemical process industries, it has not been widely used in purification unit operations in biotechnology. Recent FDA guidelines encourage the use of process modeling during process development, along with multivariate statistical methods, detailed risk assessment, and other quantifiers of uncertainty. This paper will review recent advances in the modeling of key downstream unit operations: chromatography, filtration, and centrifugation. The focus will be on the application of modeling for industrial applications. Relevant papers presented at a session on this topic at the recent American Chemical Society National Meeting in San Francisco will also be reviewed.
Quantitative reconstructions of annual rainfall in Africa 6000 years ago: Model‐data comparison
Authors: Peyron Odile , Jolly Dominique , Braconnot Pascale , Bonnefille Raymonde , Guiot Joël , Wirrmann Denis , Chalié Françoise
Published: January 2007

This paper provides the first set of quantitative reconstructions of annual precipitation for mid‐Holocene Africa, based on pollen data. The estimates of precipitation are based on 85 pollen sites 14C dated at 6000 ± 500 years B.P and distributed over the whole of Africa. To improve the reliability of the pollen‐based climate reconstruction, two methods are used: the “modern analogues technique” (MAT) and the “plant functional types” (PFT) methods. We then conduct a model‐data comparison for five distinct regions, allowing an evaluation of model outputs (the Sahara‐Sahel, the eastern Sahara, western equatorial Africa, East Africa, and Madagascar). The pollen‐inferred reconstructions are compared with 21 mid‐Holocene simulations yielded by Atmospheric General Circulation Models (AGCMs), and coupled ocean‐atmosphere‐vegetation models (OAVGCMs). The large‐scale feature of the hydrological changes is shown to be well captured by most of the models. Data show that during the mid‐Holocene, the Sahara was considerably wetter than today (+200 to +700 mm/yr). The results reinforce the conclusion that the AGCMs significantly underestimate this precipitation increase in the Sahara whereas the OAVGCM simulations are in accordance with the data. Our results show that vegetation and ocean feedbacks do not have a strong impact in the intertropical zone and that models fail to properly reproduce the climatic conditions in East Africa and Madagascar. The model‐data comparison also suggests that the lengthening of the dry season during boreal winter in the west equatorial region is a robust feature although the pollen‐based reconstruction shows no change or only slight drying there.
Proteinase K-sensitive disease-associated ovine prion protein revealed by conformation-dependent immunoassay
Authors: Thackray Alana M. , Hopkins Lee , Bujdoso Raymond
Published: January 2007

PrPSc [abnormal disease-specific conformation of PrP (prion-related protein)] accumulates in prion-affected individuals in the form of amorphous aggregates. Limited proteolysis of PrPSc results in a protease-resistant core of PrPSc of molecular mass of 27–30 kDa (PrP27–30). Aggregated forms of PrP co-purify with prion infectivity, although infectivity does not always correlate with the presence of PrP27–30. This suggests that discrimination between PrPC (normal cellular PrP) and PrPSc by proteolysis may underestimate the repertoire and quantity of PrPSc subtypes. We have developed a CDI (conformation-dependent immunoassay) utilizing time-resolved fluorescence to study the conformers of disease-associated PrP in natural cases of sheep scrapie, without using PK (proteinase K) treatment to discriminate between PrPC and PrPSc. The capture-detector CDI utilizes N-terminal- and C-terminal-specific anti-PrP monoclonal antibodies that recognize regions of the prion protein differentially buried or exposed depending on the extent of denaturation of the molecule. PrPSc was precipitated from scrapie-infected brain stem and cerebellum tissue following sarkosyl extraction, with or without the use of sodium phosphotungstic acid, and native and denatured PrPSc detected by CDI. PrPSc was detectable in brain tissue from homozygous VRQ (V136 R154 Q171) and ARQ (A136 R154 Q171) scrapie-infected sheep brains. The highest levels of PrPSc were found in homozygous VRQ scrapie-infected brains. The quantity of PrPSc was significantly reduced, up to 90% in some cases, when samples were treated with PK prior to the CDI. Collectively, our results show that the level of PrPSc in brain samples from cases of natural scrapie display genotypic differences and that a significant amount of this material is PK-sensitive.
Biosynthesis of the dystonia-associated AAA+ ATPase torsinA at the endoplasmic reticulum
Authors: Callan Anna C. , Bunning Sandra , Jones Owen T. , High Stephen , Swanton Eileithyia
Published: January 2007

TorsinA is a widely expressed AAA+ (ATPases associated with various cellular activities) ATPase of unknown function. Previous studies have described torsinA as a type II protein with a cleavable signal sequence, a single membrane spanning domain, and its C-terminus located in the ER (endoplasmic reticulum) lumen. However, in the present study we show that torsinA is not in fact an integral membrane protein. Instead we find that the mature protein associates peripherally with the ER membrane, most likely through an interaction with an integral membrane protein. Consistent with this model, we provide evidence that the signal peptidase complex cleaves the signal sequence of torsinA, and we show that the region previously suggested to form a transmembrane domain is translocated into the lumen of the ER. The finding that torsinA is a peripheral, and not an integral membrane protein as previously thought, has important implications for understanding the function of this novel ATPase.
Significantly enhanced low-frequency dielectric permittivity in the BaTiO3/poly(vinylidene fluoride) nanocomposite
Authors: Dang Zhi-Min , Xu Hai-Ping , Wang Hai-Yan
Published: January 2007

To disclose an effect of ceramic particle size on dielectric properties of BaTiO3/ poly(vinylidene fluoride) (BT/PVDF) composites at low frequency, the dielectric properties of the BT/PVDF composites loaded with different diameter BT particles at the same volume concentration were studied at wide frequency ranges from 10−1to107Hz. A significant low-frequency dielectric permittivity increase in the BT/PVDF nanocomposite was noticed, which was not reported previously. The authors considered that the marked aggrandizement of interface and dipole polarization at low frequency is charged with the significant increase in dielectric permittivity.
Estimation of absolute solvent and solvation shell entropies via permutation reduction
Authors: Reinhard Friedemann , Grubmüller Helmut
Published: January 2007

Despite its prominent contribution to the free energy of solvated macromolecules such as proteins or DNA, and although principally contained within molecular dynamics simulations, the entropy of the solvation shell is inaccessible to straightforward application of established entropy estimation methods. The complication is twofold. First, the configurational space density of such systems is too complex for a sufficiently accurate fit. Second, and in contrast to the internal macromolecular dynamics, the configurational space volume explored by the diffusive motion of the solvent molecules is too large to be exhaustively sampled by current simulation techniques. Here, we develop a method to overcome the second problem and to significantly alleviate the first one. We propose to exploit the permutation symmetry of the solvent by transforming the trajectory in a way that renders established estimation methods applicable, such as the quasiharmonic approximation or principal component analysis. Our permutation-reduced approach involves a combinatorial problem, which is solved through its equivalence with the linear assignment problem, for which O(N3) methods exist. From test simulations of dense Lennard-Jones gases, enhanced convergence and improved entropy estimates are obtained. Moreover, our approach renders diffusive systems accessible to improved fit functions.
Large magnetoelectric susceptibility: The fundamental property of piezoelectric and magnetostrictive laminated composites
Authors: Zhai Junyi , Li Jiefang , Viehland D. , Bichurin M. I.
Published: January 2007

The magnetoelectric (ME) susceptibility (αme) is the fundamental property that describes the coupling between the polarization and magnetization of a ME media. It is a complex quantity (αme*) which has rarely been studied. Here, we report investigations of the ME susceptibility for various ME laminated composites, which demonstrates that αme is on the order of 10−7s∕m for these materials, which is dramatically larger than that of single phase materials.
One-dimensional ordering of Ge nanoclusters along atomically straight steps of Si(111)
Authors: Sekiguchi Takeharu , Yoshida Shunji , Itoh Kohei M. , Mysliveček Josef , Voigtländer Bert
Published: January 2007

Ge nanostructures grown by molecular beam epitaxy on a vicinal Si(111) surface with atomically well-defined steps are studied by means of scanning tunneling microscopy and spectroscopy. When the substrate temperature during deposition is around 250°C, Ge nanoclusters of diameters less than 2.0nm form a one-dimensional array of the periodicity 2.7nm along each step. This self-organization is due to preferential nucleation of Ge on the unfaulted 7×7 half-unit cells at the upper step edges. Scanning tunneling spectroscopy reveals localized electronic states of the nanoclusters.
Tuning the threshold voltage of organic field-effect transistors by an electret encapsulating layer
Authors: Scharnberg M. , Zaporojtchenko V. , Adelung R. , Faupel F. , Pannemann C. , Diekmann T. , Hilleringmann U.
Published: January 2007

Here, the authors present a technique to adjust the threshold voltage of an organic field-effect transistor (OFET) using a design similar to a dual-gate structure with an insulating Teflon-based electret layer as a second gate. The threshold voltage of a pentacene bottom gate OFET was shifted from +13.1to−2.3V by depositon of a 1.7μm thick electret layer, proving the principal feasibility of this approach. This controlled tuning of the threshold voltage compensates one of the main drawbacks of organic electronics and even allows switching from a depletion to an enhancement-type transistor behavior.
Doping effect of multiwall carbon nanotubes on the microwave electromagnetic properties of NiCoZn spinel ferrites
Authors: Han Mangui , Deng Longjiang
Published: January 2007

NiCoZn ferrites have been found exhibiting two well separated resonance peaks. One is due to domain wall movement at 1.76GHz. One is due to spin rotation at 6.80GHz. With increasing the content of multiwall carbon nanotubes (MWCNTs) in the NiCoZn ferrite/MWCNT/wax hybrid composites, both resonance peaks are maintained, but their peak positions are found dependent on the MWCNT content. The damping factor for spin rotation is found decreasing as the content of MWCNT in composites increases. The dielectric loss of hybrid composites is also found significantly increased by increasing the content of MWCNT. The doping effects of MWCNT are thought due to the interaction between the ferrite and MWCNT. The microwave permeability of pure MWCNT has also been investigated, and it is believed due to the residual nanosized Ni particles.
Enhancement of learning and memory after activation of cerebral Rho GTPases
Authors: Diana Giovanni , Valentini Giovanni , Travaglione Sara , Falzano Loredana , Pieri Massimo , Zona Cristina , Meschini Stefania , Fabbri Alessia , Fiorentini Carla
Published: January 2007

The mechanism whereby the morphology and connectivity of the dendritic tree is regulated depends on an actin dynamics that, in turn, is controlled by Rho GTPases, a family of small GTP-binding proteins encompassing Rho, Rac, and Cdc42 subfamilies. Cytotoxic necrotizing factor 1 (CNF1), a protein toxin from
Escherichia coli
, constitutively activates Rho GTPases, thus leading to remodeling of the actin cytoskeleton in intact cells. Here, we show that the modulation of cerebral RhoA and Rac1 activity induced by CNF1 in mice leads to (
i
) rearrangement of cerebral actin cytoskeleton, (
ii
) enhanced neurotransmission and synaptic plasticity, and (
iii
) improved learning and memory in various behavioral tasks. The effects persist for weeks and are not observed in mice treated with a recombinant CNF1, in which the enzymatic activity was abolished by substituting serine to cysteine at position 866. The results suggest that learning ability can be improved through pharmacological manipulation of neural connectivity.
Coating Urinary Catheters with an Avirulent Strain ofEscherichia colias a Means to Establish Asymptomatic Colonization
Authors: Trautner Barbara W. , Hull Richard A. , Thornby John I. , Darouiche Rabih O.
Published: January 2007

We investigated whether insertion of urinary catheters that had been coated withEscherichia coliHU2117 could establish bladder colonization with this nonvirulent organism. Ten of 12 subjects were successfully colonized for 14 days or more. The rate of symptomatic UTI during colonization was 0.15 per 100 patient-days.
Function of theCaenorhabditis elegansABC Transporter PGP-2 in the Biogenesis of a Lysosome-related Fat Storage Organelle
Authors: Schroeder Lena K. , Kremer Susan , Kramer Maxwell J. , Currie Erin , Kwan Elizabeth , Watts Jennifer L. , Lawrenson Andrea L. , Hermann Greg J.
Published: January 2007

Caenorhabditis elegans gut granules are intestine specific lysosome-related organelles with birefringent and autofluorescent contents. We identified pgp-2, which encodes an ABC transporter, in screens for genes required for the proper formation of gut granules. pgp-2(−) embryos mislocalize birefringent material into the intestinal lumen and are lacking in acidified intestinal V-ATPase–containing compartments. Adults without pgp-2(+) function similarly lack organelles with gut granule characteristics. These cellular phenotypes indicate that pgp-2(−) animals are defective in gut granule biogenesis. Double mutant analysis suggests that pgp-2(+) functions in parallel with the AP-3 adaptor complex during gut granule formation. We find that pgp-2 is expressed in the intestine where it functions in gut granule biogenesis and that PGP-2 localizes to the gut granule membrane. These results support a direct role of an ABC transporter in regulating lysosome biogenesis. Previously, pgp-2(+) activity has been shown to be necessary for the accumulation of Nile Red–stained fat in C. elegans. We show that gut granules are sites of fat storage in C. elegans embryos and adults. Notably, levels of triacylglycerides are relatively normal in animals defective in the formation of gut granules. Our results provide an explanation for the loss of Nile Red–stained fat in pgp-2(−) animals as well as insight into the specialized function of this lysosome-related organelle.
Impact of Intrascalar Blood on Hearing
Authors: Radeloff Andreas , Unkelbach Marc H. , Tillein Jochen , Braun Susanne , Helbig Silke , Gstöttner Wolfgang , Adunka Oliver F.
Published: January 2007

Objective/Hypothesis: The objective of this controlled animal study was to evaluate the effects of intrascalar blood on hearing.

Material and Methods: Eight guinea pigs underwent intrascalar administration of their own blood in one ear and control solution in the contralateral ear. Solutions were applied through cochleostomy to the scala tympani. Compound action potential (CAP) thresholds were determined before administration and at different intervals for 2 months thereafter.

Results: Immediate deterioration of thresholds was seen mainly in the high‐frequency range, averaging 27 dB and 20 dB in the study and control groups, respectively. At day 3, threshold shifts recovered in the control group but remained in the low‐frequency range in the study group. An extensive recovery was seen in both groups. However, permanent threshold shifts persisted. There was an enhanced shift of thresholds of up to 7 dB in the study group.

Conclusions: Even small amounts of intrascalar blood seem to cause transient and permanent detrimental effects on cochlear function. In procedures involving opening of the otic capsule—like stapes surgery and cochlear implantation with hearing preservation—minimizing surgical blood admixture to intracochlear compartments seems therefore fundamental.
Electromyographic Findings After Different Selective Neck Dissections
Authors: Tsuji Tetsuya , Tanuma Akira , Onitsuka Tetsuro , Ebihara Mitsuru , Iida Yoshiyuki , Kimura Akio , Liu Meigen
Published: January 2007

Objectives: The objective was to compare electrophysiologic investigations of the upper trapezius muscle (UT) after different selective neck dissections (SND) and analyze the differences between types of SND and the preservation and excision of the cervical nerves (the C2–4 rami of the cervical plexus).

Study Design: Retrospective study of 54 patients (average age, 65.1 ± 9.6 yr, 45 males) with 70 SND.

Methods: Patients underwent needle electromyography (EMG) of the UT by 4 months after surgery. The findings were rated according to the 5 point EMG scale system from 1 (total denervation: positive sharp wave or fibrillation potential at rest and electrical silence at voluntary contraction) to 5 (normal pattern).

Results: The average EMG scale was 1.7 ± 1.1, 58.6% for score 1 and only 5.7% for score 5. There was not a significant difference in the EMG scale between the types of SND, whereas the group in which the cervical nerves were excised was significantly lower than in that in which it was preserved. The average EMG scales in the former and latter were 1.5 ± 0.8 and 2.0 ± 1.3, 68.8%.

Conclusions: The study data confirm that complete or incomplete denervation of the UT was caused by axonal injury of the spinal accessory nerve, even though it was spared, because of traction of the nerve during neck dissection. Second, the excision of the C2 to 4 rami of the cervical plexus caused worse damage of the UT. It is suggested that it is important to preserve the cervical nerves to avoid denervation of the UT.
Impact of Re‐resection for Inadequate Margins on the Prognosis of Upper Aerodigestive Tract Cancer Treated by Laser Microsurgery
Authors: Jäckel Martin C. , Ambrosch Petra , Martin Alexios , Steiner Wolfgang
Published: January 2007

Objectives: Positive or uncertain surgical margins left untreated have a distinct prognostic relevance in squamous cell carcinoma of the upper aerodigestive tract. An advantage of transoral laser microsurgery is that it can be easily repeated if inadequate resection margins are found postoperatively. The present study investigates the impact of laser surgical reresection on the outcome of patients.

Study Design: The authors conducted a retrospective unicenter study.

Methods: A review of 1,467 patients with squamous cell carcinoma of the upper aerodigestive tract who were initially treated by transoral laser microsurgery with curative intent between August 1986 and December 2002 was conducted. Locoregional control as well as TNM adjusted and overall survival were analyzed using the Kaplan‐Meier method.

Results: Three hundred eighty‐six patients have required reresection to obtain clear surgical margins, in 70 of whom residual carcinoma has been detected in revision specimens. Patients without need for revision and those in whom revision specimens were found tumor‐free had an almost identical locoregional control (P = .4611). In patients with positive revision specimens, however, locoregional control was significantly worsened (P = .0058). Neither the need for reresection nor the detection of further tumor tissue in revision specimens affected TNM adjusted or overall survival.

Conclusions: Survival of patients was similar whether clear resection margins were reached within the first surgical step or with revision surgery. However, patients in whom reresection specimens contained residual carcinoma had an increased risk of locoregional failure and should undergo a further reresection or at least a very close follow up.
Effects of High versus Standard Early Protein Intake on Growth of Extremely Low Birth Weight Infants
Authors: Maggio Luca , Cota Francesco , Gallini Francesca , Lauriola Valeria , Zecca Chiara , Romagnoli Costantino
Published: January 2007

Objectives:

Early provision of protein has been shown to limit catabolism and could improve growth. Our objective was to determine whether early aggressive protein intake improved growth outcomes of extremely low birth weight (ELBW) infants.

Patients and Methods:

ELBW infants were included in the study if they had no major congenital anomalies or renal failure and were still hospitalized at 36 weeks postmenstrual age. In 25 infants (HP) the early protein intake was planned to be 20% greater than in 31 historical controls (SP).

Results:

The 2 groups were similar in the baseline characteristics. The mean protein intake during the first 14 days of life was significantly greater in the HP group (3.1 ± 0.2 vs 2.5 ± 0.2 g/kg/d; P<0.0001). HP group showed lower postnatal weight loss (−3.1%; 95% confidence interval [CI] −5.9, −0.2) and earlier regain of birth weight (−4.1 days; 95% CI −6.6, −1.7). Mean blood urea nitrogen and bicarbonate levels were similar; mean serum glucose level was lower in the HP group (−21,7 mg/dL; 95% CI −41.9,−1.5). HP infants had a reduced fall in weight z score (−0.57; 95% CI −1.01, −0.12) and in length z score (−0.51; 95% CI −0.97, −0.05) from birth to discharge.

Conclusion:

Early high protein intake was associated with improved weight and length growth outcomes at discharge. These findings highlight the benefits of aggressive protein intake immediately after birth.
Double‐blind, Placebo‐controlled Trial Comparing Effects of Supplementation of Two Micronutrient Sprinkles on Fatty Acid Status in Cambodian Infants
Authors: Agostoni Carlo , Giovannini Marcello , Sala Debora , Usuelli Michele , Livio Luca , Francescato Gaia , Braga Marta , Riva Enrica , Martiello Antonella , Colombo Claudio , Marangoni Franca , Galli Claudio
Published: January 2007

Background:

Infants in developing countries require early dietary interventions to prevent nutritional deficiencies, above all protein, energy, iron and zinc. To what extent these interventions may affect the fatty acid (FA) status is still unknown.

Objectives:

To examine and compare the effects of 2 micronutrient “sprinkles” supplementations (iron 12.5 mg + folic acid 150 μg, iron/folate and iron 12.5 mg + folic acid 150 μg + zinc 5 mg + vitamins A, C and D3, mineral/micronutrient [MMN]) versus placebo on the FA status of Cambodian infants.

Methods:

A total of 204 infants age 6 mo and living in Kompong Chhnang Province, Cambodia, were randomly assigned to receive daily supplementation of MMN (n = 68) and iron/folate (n = 68) or placebo (n = 68) for a 12‐mo period in powder form as sprinkles. At the end of the intervention period, FAs in the range of 16 to 24 C were determined in blood drops absorbed on a strip collected from 182 subjects, and values among the 3 intervention subgroups and those of 21 Italian 18‐mo‐old, normal‐growing infants as the reference group were compared.

Results:

At the end of the supplementation trial, higher levels of the 2 essential FAs (EFAs) (linoleic acid, 18:2n‐6, and α‐linolenic acid, 18:3n‐3) were found in the MMN group. No differences occurred for the major longer chain derivatives of both EFAs arachidonic acid (20:4n‐6) and docosahexaenoic acid (22:6n‐3). In MMN supplemented Cambodians, blood levels of linoleic acid approached those of Italian infants, and in addition their α‐linolenic acid levels were improved. Cambodian infants, mostly still breast‐fed through the second year of life, showed significantly higher levels of long‐chain derivatives of both the n‐6 and the n‐3 series compared with Italians.

Conclusions:

Supplementation with iron, folic acid, zinc and vitamins was associated with an increase of linoleic acid and α‐linolenic acid levels in Cambodian infants versus placebo, without significant changes in the concentrations of their longer chain derivatives, resulting in a FA status closer to Italian counterparts for the essential polyunsaturated FA levels. The iron/folate–treated infants showed no differences compared with the other 2 groups. Studies are needed to differentiate the potential effects of the supplemented micronutrients on the FA status.
Whole‐specimen histopathology: a method to produce whole‐mount breast serial sections for 3‐D digital histopathology imaging
Authors: Clarke G M , Eidt S , Sun L , Mawdsley G , Zubovits J T , Yaffe M J
Published: January 2007

Aims:  To develop a method for preparing diagnostic‐quality, whole‐mount serial sections of breast specimens while preserving 3‐D conformation. This required supporting the fresh specimen prior to breadloafing and refining the conventional tissue processing method. The overall goal is to use digital images of whole‐specimen histopathology to improve the estimation of extent of disease.

Methods and results:  To maintain a 3‐D conformation, the specimen is suspended in 3.5% agar at 55°C. The block is sliced at 5‐mm intervals. Sectioning is performed after extended fixation in 4% formaldehyde from paraformaldehyde in 0.1 m Millonig's buffer, followed by paraffin processing using a non‐routine schedule and extended paraffin infiltration. Whole‐mount serial breast sections are produced with features of equal or superior quality to that which can be achieved using conventional methods. The method is compatible with some immunohistochemical stains but requires further optimization for others.

Conclusions:  The technique is currently suitable for research applications. With the reduction in processing time achievable with microwave‐assisted processing, there is the potential for its use as a routine clinical method. This tool may improve the accuracy of margin estimates and identification of multifocality in breast cancer; further evaluation is necessary.
Relational ethics and advocacy in nursing: literature review
Authors: MacDonald Hannah
Published: January 2007

Title. Relational ethics and advocacy in nursing: literature review

Aim. The purpose of this paper is to analyse themes from accounts of nurses’ experiences with advocacy that may expand our understanding of advocacy in nursing practice.

Background. Although the ethical obligation to advocate is universal, a lack of clarity persists about the nature of advocacy in nursing practice.

Method. This discussion of advocacy is based on a synthesis of qualitative studies that focus on nurses’ experiences with advocacy in practice. Empirical studies were retrieved through searches on the CINAHL and Academic Search Premier databases for the years 1993–2005. The search terms used were advocacy, advocate role, ethics, nursing practice and qualitative research.

Findings. Empirical studies related to the role of advocacy in nursing are limited in number. Nurses’ experiences with advocacy reveal important themes in relation to factors that influence the application of advocacy in nursing practice. Evidence suggests that the nature and context of relationships plays a significant role in influencing the enactment of advocacy.

Conclusion. The application of advocacy in nursing practice is complex. The philosophy of relational ethics emphasizes the contextual features of relationships. An examination of relational ethics as it applies to advocacy in nursing brings us closer to a deeper understanding of the process by which nurses make advocacy choices in practice, and raises implications for the development of advocacy in nurses’ practice. Advocacy is universally considered a moral obligation in nursing practice, and thus advancement of our knowledge about its nature in nursing is relevant to nursing across multiple contexts and cultures.
Cutaneous manifestations of Costello syndrome
Authors: Nguyen Victoria , Buka Robert L. , Roberts Brandie J. , Eichenfield Lawrence F.
Published: January 2007

Cutaneous findings are common in Costello syndrome, but have not been extensively reviewed in the dermatology literature. We present the cutaneous and histopathologic findings from two cases of Costello syndrome and review previously described cutaneous features of this syndrome. Both patients had manifestations of Costello syndrome with thick, lax skin on the dorsal aspects of hands and feet, deep palmar and plantar creases, curly hair, hyperkeratoses, acanthosis nigricans, papillomas, and multiple pigmented lesions. One patient had multiple syringomas on the forearms, a finding not previously reported. Pigmented lesions have previously been reported as nevi in the literature though no biopsies have been reported. We conclude that thick, loose skin on the dorsal aspects of hands and feet and deep palmar and plantar creases are cardinal manifestations of Costello syndrome and benign tumors of ectodermal origin such as papillomas, calcified epitheliomas, dermoid cysts, mammary fibroadenosis, and syringomas are important features of this syndrome.