bluuebunny/crossref_metadata_2025 huggingface dataset:
Trends and lacunae for future computer assisted learning (CAL) research: An assessment of the literature in SSCI journals from 1998–2006
Authors: Luor Ted (Tainyi) , Johanson Robert E. , Lu Hsi‐Peng , Wu Ling‐ling
Published: April 2008

This study surveyed 536 CAL publications in 71 SSCI (Social Science Citation Index) journals from 1998 to February 2006 to identify trends and lacunae for future research. The parameters and keywords employed by the authors are first presented, followed by a description of the study's general findings. A comparison is then drawn between CAL and recent depictions of the “blogosphere,” for the majority of the contributors to the field produced only a few articles and authors of individual publications demonstrated a far greater collective influence on the field than the more frequently‐cited authors. Results also revealed that the amount of articles pertaining to the aged, disabled children, and home schooling were significantly lower than those relating to school student's learning. This study offers an interesting snapshot of a field that is apparently on the rise; moreover, it raises some issues to be addressed in further research on CAL‐related topics.
Androgen deprivation falls as orchiectomy rates rise after changes in reimbursement in the U.S. Medicare population
Authors: Weight Christopher J. , Klein Eric A. , Jones J. Stephen
Published: April 2008

BACKGROUND

Expenditures related to the use of medical androgen deprivation led in part to the Medicare Modernization Act (MMA) in 2003. This mandated a decline in reimbursement to 80% to 85% of the average wholesale price starting in 2004 followed by a more significant reduction in 2005 to 106% of the average sales price, which effectively reduced the reimbursement by approximately 50% of 2003 values. The authors hypothesized that these changes in reimbursement may affect the way practitioners administer these treatments.

METHODS

The publicly available dataset Medicare Part B Extract Summary System was examined from 2001 to 2005 for trends in the number of allowed services and dollar amounts of allowed charges and payments. The reimbursable Medicare codes of J9217 (leuprolide acetate), J9202 (goserelin acetate), J9219 (leuprolide acetate implant), and J3315 (triptorelin pamoate) were examined for medical castration. The code for simple orchiectomy, 54520, was used for surgical castration.

RESULTS

The use of medical castration increased from 2001 to 2003, whereas, over the same period, surgical castration decreased. Total allowed charges for medical castration peaked in 2003 at $1.23 billion. After the enactment of the MMA, surgical castration rates increased, and medical castration decreased. Total allowed charges for medical castration in 2005 dropped 65% from the 2003 peak.

CONCLUSIONS

The use of medical androgen ablation decreased significantly with the decrease in reimbursement. The administration of either surgical or medical castration in the U.S. Medicare population appears to be tied closely to reimbursement in trend, but not always in magnitude. Cancer 2008. © 2008 American Cancer Society.
Function of Pax1 and Pax9 in the sclerotome of medaka fish
Authors: Mise Takeshi , Iijima Minoru , Inohaya Keiji , Kudo Akira , Wada Hiroshi
Published: April 2008

We examined the expression and functions of Pax1 and Pax9 in a teleost fish, the medaka Oryzias latipes. While Pax1 and Pax9 show distinct expression in the sclerotome in amniotes, we could not detect the differential expression of Pax1 and Pax9 in the developing sclerotome of the medaka. Furthermore, unlike the mouse, in which Pax1 is essential for development of the vertebral body, and where the neural arch is formed independent of either Pax1 or Pax9, our morpholino knockdown experiments revealed that both Pax1 and Pax9 are indispensable for the development of the vertebral body and neural arch. Therefore, we conclude that after gene duplication, Pax1 and Pax9 subfunctionalize their roles in the sclerotome independently in teleosts and amniotes. In Stage‐30 embryo, Pax9 was strongly expressed in the posterior mesoderm, as was also observed for mouse Pax9. Since this expression was not detected for Pax1 in the mouse or fish, this new expression in the posterior mesoderm likely evolved in Pax9 of ancestral vertebrates after gene duplication. Two‐month‐old fish injected with Pax9 morpholino oligonucleotide showed abnormal morphology in the tail hypural skeletal element, which may have been related to this expression. genesis 46:185–192, 2008. © 2008 Wiley‐Liss, Inc.
Use of ERT2‐iCre‐ERT2 for conditional transgenesis
Authors: Jullien Nicolas , Goddard Isabelle , Selmi‐Ruby Samia , Fina Jean‐Luc , Cremer Harold , Herman Jean‐Paul
Published: April 2008

We examined the use of ERT2‐iCre‐ERT2 (Cre2ERT2), a tamoxifen‐regulated form of Cre that has been described to have a background activity lower than that of other tamoxifen‐regulated Cre constructs, for establishing performant conditional deleter mouse lines. Cre2ERT2 was inserted by homologous recombination into the Rosa26 locus. These mice were mated with R26R Cre‐reporter mice. No recombination could be observed in the progenies in the absence of tamoxifen treatment. Tamoxifen treatment at E13‐14 led to a high level, albeit variable, recombination in most of the tissues examined: liver, heart, kidney, brain, lung etc. Treatment of adult animals also induced recombination in these tissues, although at a lower level. Northern blot and qPCR studies suggested that these differences are not linked to significant variations of the level of expression of Cre2ERT2. Thus, Cre2ERT2 appears to be a good alternative to existing modulatable Cre systems, displaying a lack of background activity and a high‐level inducibility in vivo. genesis 46:193–199, 2008. © 2008 Wiley‐Liss, Inc.
Mouse Dach1 and Dach2 are redundantly required for Müllerian duct development
Authors: Davis Richard J. , Harding Mark , Moayedi Yalda , Mardon Graeme
Published: April 2008

dachshund/Dach gene family members encode transcriptional cofactors with highly conserved protein interaction domains and are expressed in the developing eyes, brains, and limbs in insects and vertebrates. These observations suggest that the developmental roles of dachshund/Dach in these tissues have been conserved since the divergence of arthropods and chordates. However, while Drosophila dachshund mutants have abnormalities in eye, brain, limbs, mouse Dach1 or Dach2 knockout mutants do not exhibit gross anatomical malformations in these tissues. In addition, Dach1/2 double homozygotes have intact eyes and limbs. Here we show that in Dach1/Dach2 double mutants, female reproductive tract (FRT) development is severely disrupted. This defect is associated with the Müllerian duct (MD) and not the Wolffian duct (WD), which normally differentiate into either the FRT or male reproductive tract (MRT), respectively. Dach1 and Dach2 are expressed in the MD, and in Dach1/2 double mutants, MD expression of Lim1 and Wnt7a is abnormal and MD development is disrupted. In contrast, WD and MRT development are not grossly affected. We propose that Dach1 and Dach2 proteins may redundantly control FRT formation by regulating the expression of target genes required for development of the MD. This vertebrate Dach1/2 function may have been conserved during arthropod evolution, as Drosophila dachshund mutants also exhibit an FRT phenotype. genesis 46:205–213, © 2008 Wiley‐Liss, Inc.
Mechanical and flow characterization of Sponceram® carriers: Evaluation by homogenization theory and experimental validation
Authors: Sanz‐Herrera Jose A. , Kasper Cornelia , van Griensven Martijn , Garcia‐Aznar Jose M. , Ochoa Ignacio , Doblare Manuel
Published: April 2008

The experimental evidence of the dependence of cell proliferation and differentiation in vitro on the mechanical environment aims to the need of characterization of porous scaffolds in terms of mechanical and flow properties. In this sense, the Young's modulus and intrinsic permeability for three types of Sponceram® cell carriers developed for in‐vitro applications are here analyzed. Young's modulus and ultimate compression stress were obtained by performing a two‐plates compression test carried out in a universal microtester machine Instron® for several representative samples of each specimen. A permeability test was also implemented to correlate flow rate and pressure gradient in the linear range. Furthermore, porosity and specific surface were obtained through micro‐CTs of the scaffold microstructure. These experimental data were compared with those obtained numerically by homogenization for several representative volume elements (RVEs) of the scaffolds microstructure. The good agreement found between numerical and experimental results let us consider that the use of numerical techniques is an attractive tool for the analysis of complex scaffold microstructures. Moreover, Sponceram® carriers are shown to have very appropriate properties as bone bioscaffolds which let us recommending further clinical and numerical research on these specific materials. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Molecular parameters of genome instability: Roles of fragile genes at common fragile sites
Authors: Pichiorri Flavia , Ishii Hideshi , Okumura Hiroshi , Trapasso Francesco , Wang Ya , Huebner Kay
Published: April 2008

Common chromosome fragile sites occur at specific sequences within mammalian genomes that exhibit apparent single‐stranded regions in mitotic chromosomes on exposure of cells to replication stress. Recent progress in the characterization of sequences, and more precise mapping of common fragile sites in mammalian and yeast genomes, has led to the exact placement of large common fragile regions straddling the borders of chromosomal G and R bands, with early and late replicating genomic regions, respectively, and could lead to breakthroughs in understanding the function of these evolutionarily conserved but highly recombinogenic chromosome elements. Deficiency of genes involved in DNA damage checkpoint responses, such as ATR, CHK1, HUS1 leads to increased frequency of fragile site instability. Some of these fragile sites, particularly FRA3B, encode genes that are themselves involved in the protection of cells from DNA damage through various mechanisms. Protection of mammalian genomes from accumulation of DNA damage in somatic cells is critical during development, puberty and during the reproductive lifespan, and occurs through mechanisms involving surveillance of the genome for damage, signals to the cell cycle machinery to stop cell cycle progression, signals to repair machinery to repair damage, signals to resume cycling or initiate apoptotic programs, depending on the extent of damage and repair. When genes involved in these processes are altered or deleted, cancer can occur. The tumor suppressor gene, FHIT at the FRA3B locus, and possibly other fragile genes, is a common target of damage and paradoxically encodes a protein with roles in protection from DNA damage. J. Cell. Biochem. 104: 1525–1533, 2008. © 2008 Wiley‐Liss, Inc.
Small applied electric fields guide migration of hippocampal neurons
Authors: Yao Li , Shanley Lynne , McCaig Colin , Zhao Min
Published: April 2008

Effectively directed neuron migration is critical for development and repair in the central nervous system (CNS). Endogenous electric fields (EFs) are widespread in developing and regenerating tissues and regulate a variety of cell behaviors including directed cell migration. Electrically‐directed neuronal migration has not been tested previously and we show that an applied EF directs migration of hippocampal neurons toward the cathode at a field strength of 120 mV/mm, close to the physiological range. Reversal of the field polarity reversed the direction of neuron migration. Neuron migration from an explant also was directed by an applied EF. Mechanistically, EF‐guided migration was transduced by activation of the second messenger molecules ROCK (Rho‐associated protein kinase) and PI3 kinase (phosphoinositide‐3 kinase) since their pharmacological inhibition decreased the directedness and speed of neuron migration. This work demonstrates that rat hippocampal neurons respond to applied EFs with directional migration and raises the possibility that EFs may be used as a cue to direct neuronal migration in novel strategies to repair the CNS. J. Cell. Physiol. 216: 527–535, 2008. © 2008 Wiley‐Liss, Inc.
First‐trimester diagnosis of cesarean scar ectopic pregnancy
Authors: Moschos Elysia , Sreenarasimhaiah Sreedevi , Twickler Diane M.
Published: April 2008

Once considered extremely rare, implantation of a pregnancy within the scar of a previous cesarean section is becoming more common. In fact, its incidence is now higher than that of cervical ectopic pregnancies. We identified 5 cases of ectopic pregnancy implanted in a prior cesarean section scar at our institution since 2004. We outline the criteria for the first‐trimester sonographic diagnosis of cesarean scar ectopic pregnancy, including a new sign of lower uterine segment ballooning, which has previously not been reported. Clinicians must have a heightened awareness of this serious and potentially fatal pregnancy complication. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008.
An identification of stem cell‐resembling gene expression profiles in high‐grade astrocytomas
Authors: Yang Yang , Qiu Yongming , Ren Wenwen , Gong Jialei , Chen Fuxue
Published: April 2008

High‐grade astrocytomas are among the most intractable types of cancers and are often fatal. Previous studies have suggested that high‐grade astrocytomas may adopt the self‐renewal and migration properties of neural stem cells (NSCs) to proliferate and spread by expressing the stem cell‐specific genes. However, despite a few common molecules being documented, the molecular basis underlying these similarities remains largely unknown. To have a better understanding of the stem cell characteristics of high‐grade astrocytomas, we performed the study to identify the stem cell‐resembling gene expression profile in high‐grade astrocytomas. cDNA microarray analysis was used to detect the differentially expressed genes of isolated human high‐grade astrocytomas versus their peritumoral tissue counterparts, and the identification of stem cell‐resembling genes was approached by comparing the high‐grade astrocytomas‐specific gene expression profile with that of NSCs identified by our previous study and other groups. We identified more than 200 high‐grade astrocytomas‐specific genes in this study, and near 10% genes or gene families of them exhibited similar up or down expression patterns as in NSCs. Further analysis indicated that these genes were actively involved in cell proliferation, adhesion, migration, and metastasis. This study revealed a list of stem cell‐specific genes in high‐grade astrocytomas, which was likely to have critical roles in determining the “stem” characteristics of high‐grade astrocytomas. © 2008 Wiley‐Liss, Inc.
ERp29, an endoplasmic reticulum secretion factor is involved in the growth of breast tumor xenografts
Authors: Mkrtchian Souren , Baryshev Mikhail , Sargsyan Ernest , Chatzistamou Ioulia , Volakaki Aspasia‐Athina , Chaviaras Nick , Pafiti Agatha , Triantafyllou Aggeliki , Kiaris Hippokratis
Published: April 2008

Cancer cells are committed to an actively secretory state that facilitates communication with their microenvironment. We have addressed the role of ERp29, a novel endoplasmic reticulum secretion factor in mammary carcinogenesis using MCF‐7 human breast cancer cells as a model. Xenografts originating from cells stably transfected with dominant‐negative form of ERp29 were smaller and better differentiated than those derived from cells overexpressing wild‐type ERp29. Similar effects were observed by siRNA‐mediated ERp29 silencing in xenografts. However, unlike xenografts, the modulation of ERp29 in vitro did not affect the rate of cell proliferation. In addition, we have evaluated the expression of ERp29 in the resting and lactating mammary glands of mice as well as in the human primary breast tumors. About 25% of breast cancers and also lactating mammary glands were expressing ERp29 while the resting glands did not. Taken together these data suggest the active involvement of ERp29 in the malignant conversion of mammary epithelial cells. © 2008 Wiley‐Liss, Inc.
A model testing factors that influence physical activity for Taiwanese adults with anxiety
Authors: Ma Wei‐Fen , Lane Hsien‐Yuan , Laffrey Shirley C.
Published: April 2008

The aim of this study was to test a theoretical model of the facilitators and barriers to physical activity for Taiwanese adults with anxiety. Structural equation modeling was used to examine both one‐way direct and indirect influences of 11 personal and cognitive‐emotional factors on physical activity in this population (N = 239). The final version of the model provided a good fit to the data, with nine variables explaining 23.3% of the variance in physical activity. Perceived life stress events, perceived benefits of activity, and perceived self‐efficacy for activity directly influenced physical activity. The results suggest that these variables should be addressed in designing treatment physical activity programs for Taiwanese individuals with anxiety. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:476–489, 2008
Structure and folding of disulfide‐rich miniproteins: Insights from molecular dynamics simulations and MM‐PBSA free energy calculations
Authors: Combelles Cecil , Gracy Jérôme , Heitz Annie , Craik David J. , Chiche Laurent
Published: April 2008

The fold of small disulfide‐rich proteins largely relies on two or more disulfide bridges that are main components of the hydrophobic core. Because of the small size of these proteins and their high cystine content, the cysteine connectivity has been difficult to ascertain in some cases, leading to uncertainties and debates in the literature. Here, we use molecular dynamics simulations and MM‐PBSA free energy calculations to compare similar folds with different disulfide pairings in two disulfide‐rich miniprotein families, namely the knottins and the short‐chain scorpion toxins, for which the connectivity has been discussed. We first show that the MM‐PBSA approach is able to discriminate the correct knotted topology of knottins from the laddered one. Interestingly, a comparison of the free energy components for kalata B1 and MCoTI‐II suggests that cyclotides and squash inhibitors, although sharing the same scaffold, are stabilized through different interactions. Application to short‐chain scorpion toxins suggests that the conventional cysteine pairing found in many homologous toxins is significantly more stable than the unconventional pairing reported for maurotoxin and for spinoxin. This would mean that native maurotoxin and spinoxin are not at the lowest free energy minimum and might result from kinetically rather than thermodynamically driven oxidative folding processes. For both knottins and toxins, the correct or conventional disulfide connectivities provide lower flexibilities and smaller deviations from the initial conformations. Overall, our work suggests that molecular dynamics simulations and the MM‐PBSA approach to estimate free energies are useful tools to analyze and compare disulfide bridge connectivities in miniproteins. Proteins 2008. © 2008 Wiley‐Liss, Inc.
Long‐range analysis of density fitting in extended systems
Authors: Varga Štefan
Published: April 2008

Density fitting scheme is analyzed for the Coulomb problem in extended systems from the correctness of long‐range behavior point of view. We show that for the correct cancellation of divergent long‐range Coulomb terms it is crucial for the density fitting scheme to reproduce the overlap matrix exactly. It is demonstrated that from all possible fitting metric choices the Coulomb metric is the only one which inherently preserves the overlap matrix for infinite systems with translational periodicity. Moreover, we show that by a small additional effort any non‐Coulomb metric fit can be made overlap‐preserving as well. The problem is analyzed for both ordinary and Poisson basis set choices. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Interaction of CO and NO with the spinel CuCr2O4 (100) surface: A DFT study
Authors: Xu Xiang‐Lan , Chen Wen‐Kai , Chen Zhan‐Hong , Li Jun‐Qian , Yi Li
Published: April 2008

The characteristics of CO and NO molecules at Cu2+ and Cr3+ ion sites on the CuCr2O4 (100) surface have been studied by first principles calculations based on spin‐polarized density functional theory (DFT). The calculated results show that adsorption energies for X‐down(C, N) adsorption vary in the order: Cu2+‐CO>Cr3+‐NO≈Cr3+‐CO>Cu2+‐NO. CO molecules are preferentially adsorbed at Cu sites, whereas NO molecules adsorb favorably at Cu2+ and Cr3+ ion sites. The C‐O and N‐O stretching frequencies are red‐shifted upon adsorption. Combining the analysis of frontier molecular orbitals and Mulliken charge, for CO and NO X‐down adsorption systems, the 5σ orbitals donate electrons and the 2π* orbitals obtain back‐donated electrons. Although for NO with O‐down adsorption systems, the NO‐2π* orbitals obtain back‐donated electrons from substrates without 5σ‐donation. Coadsorption calculations show the CO/NO mixture adsorb selectively at the Cu2+ion site but simultaneously at the Cr3+ ion site, respectively. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Thermal unfolding of proteins probed by laser spray mass spectrometry
Authors: Shi Xiangguo , Takamizawa Atsushi , Nishimura Yoshifumi , Hiraoka Kenzo , Akashi Satoko
Published: April 2008

The stability and conformational changes of cytochrome c (cyt c) at different temperatures and pH have been well examined so far by using various analytical methods. We have found that laser spray mass spectrometry enables much faster and more convenient monitoring of those changes of cyt c compared with other methods. The results correlated well with circular dichroism (CD) experiments under relatively acidic conditions, which destabilize the protein. Laser spray mass spectra of cyt c at various pH were obtained at different levels of laser power. Bimodal charge‐state distributions of the protein were observed in laser spray mass spectra, indicating the two‐state model of structural change; the lower charges correspond to the folded state, the higher charges to the unfolded state. Based on this result, the presumed denaturation curve of the protein was plotted as a function of laser power, and laser power by which 50% of the protein was assumed to be denatured, E50%, as obtained at each pH. We also examined the melting temperatures, Tm, of cyt c at various values of pH by using CD spectroscopy. The correlation coefficient between E50% and Tm for cyt c was 0.999, demonstrating an excellent correlation. Furthermore, laser spray analysis of ubiquitin, which is found to be more thermally stable than cyt c, gave a higher E50% than cyt c. These results indicate that laser spray mass spectrometry can be an extremely convenient method for probing thermal stabilities and dynamic conformational changes of proteins with subtle structural differences caused by slight changes in pH. Copyright © 2008 John Wiley & Sons, Ltd.
Adaptive control design for a class of nonsmooth nonlinear systems with matched and linearly parameterized uncertainty
Authors: Nakakuki Takashi , Shen Tielong , Tamura Katsutoshi
Published: April 2008

This paper presents an adaptive control design for a class of nonsmooth nonlinear systems with matched uncertainty, which is linearly parameterized with a known discontinuous function. The design framework is based on the concept of the Filippov solution as the classical Lyapunov theory for smooth systems cannot be applied to establish the stability of the adaptive control system due to the presence of the discontinuity. It is proved that as an adaptive control system, the global Lyapunov stability with the convergence of the state of the controlled system to the origin can be achieved by evaluating the monotonicity of the Lyapunov function in the state space, particularly on the discontinuous surface, while the uniqueness of the solution of the closed‐loop system is not necessarily guaranteed. Some interesting numerical examples are demonstrated with simulation results. Copyright © 2008 John Wiley & Sons, Ltd.
Equivalent chain lengths of methyl octadecadienoates and octadecatrienoates
Authors: Scholfield C. R. , Dutton H. J.
Published: April 2008

Equivalent chain lengths (ECL) have been determined for a number of methyl octadecadienoates and octadecatrienoates with different stationary phases, including Apiezon L, polyphenyl ether, diethylene glycol succinate, XF 1150, 100% cyanoethyl silicone and tetracyanoethylated pentaerythritol. ECL values for unconjugated esters are slightly larger than calculated by adding the ECL increments over stearate found for octadecenoates with the same position and configuration of double bonds. In general, differences are greater for methylene‐interrupted double bonds and fortrans double bonds. They are greater for more polar columns. Average corrections can be added so that calculated ECL values agree well with the determined values. ECL increases with polarity of the stationary phase. The relative ECL pattern on different stationary phases changes little with position of double bonds in the isomers, but it is affected by double bond configuration. For esters with the same double bond positions isomers withtrans double bonds tend to have lower ECL values thancis on polar stationary phases and higher ECL values on nonpolar. ECL’s of conjugated octadecadienoates are always higher than unconjugated and increase in the ordercis,cis; mono‐trans; andtrans,trans.
Alkyl azelaaldehydates of high purity from alkyl soyates: Preparation and properties
Authors: Awl R. A. , Pryde E. H. , Weisleder D. , Rohwedder W. K. , Cowan J. C.
Published: April 2008

Reductive ozonolysis of appropriate alkyl soyates in various participating media producted methyl, ethyl,n‐propyl, isopropyl andn‐butyl azelaaldehydates in good yield and high purity (98+%). The participating media examined were: methyl, ethyl,n‐propyl andn‐butyl alcohols; mixtures of an alcohol and acetic acid; water; and mixtures of water and acetic acid. Any combination of solvent and ester, except methanol‐methyl soyate, allowed good separation by fractional distillation of ester and acetal impurities from the azelaaldehydate. A preparative method was developed by which high purity ethyl azelaaldehydate is produced from soybean oil by reductive ozonolysis in water. The only major impurity by this method was ethyl hydrogen azelate, which was easily removed with a bicarbonate wash. After a single fractional distillation with a short Vigreux column, the azelaaldehydate was obtained in 78% yield and 98+% purity. Physical properties and spectral (IR, NMR and mass spectroscopy) and chromatographic data were determined for the pure alkyl azelaaldehydates. Several of these properties were also determined for acetal and diester byproducts.
A rapid screening technique for determining the lipid composition of soybean seeds
Authors: Dahmer Mark L. , Fleming Pierce D. , Collins Glenn B. , Hildebrand David F.
Published: April 2008

An efficient method to determine the fatty acid composition of a large number of small seed tissue samples is needed to facilitate the genetic manipulation of seed lipid composition in soybean and other oilseeds. A rapid procedure has been developed to simultaneously extract and transmethylate the neutral lipids from soybean cotyledons at 90°C in a mixture of hexane and 1% H2SO4 in methanol (pretreatment of cotyledon pieces with hexane prior to methanolysis was found to improve yields). Fatty acid methyl esters were analyzed by capillary or packed column gas chromatography. The method required less than 10 mg of cotyledon tissue which could be taken from opposite the embryo axis so the sampled seed remained viable.

This direct transmethylation method was compared to Soxhlet extraction and subsequent acid methanolysis and to methods requiring separate steps for extraction [with hexane alone, hexane:isopropanol (3:2) or chloroform:methanol (2:1)], washing, solvent removal and methanolysis. Determinations of fatty acid content and composition were similar among the four methods. Approximately 30 times more samples could be analyzed (more than 2000 samples per month) using the direct transesterification method than were possible with the Soxhlet procedure. This direct transmethylation method is more rapid, requires less tissue, and provides results comparable to other inexpensive methods. It should be especially useful in breeding studies where large numbers of small samples are encountered.
The extraction of natural cashew nut‐shell liquid from the cashew nut (Anacardium occidentale)
Authors: Tyman J. H. P. , Johnson R. A. , Muir M. , Rokhgar R.
Published: April 2008

In the two‐stage recovery of natural cashew nut‐shell liquid (CNSL) by solvent extraction, the overall yields from half‐shells obtained by mechanical cutting and from chilled fragmented shells (to solidify the phenols) by manual processing are identical, indicating that no physical loss of phenolic material occurs in the mechanical process. At the first stage, prior to comminution, the yield from intact half‐shells of mechanical origin is considerably less than that from manually processed shells due to extensive internal fracturing of the shell structure and greater solvent penetration in the latter case. Static solvent extraction of macerated shells gave the same yield as Soxhlet extraction, but the filtration stage was difficult and large volumes of solvent were required. Soxhlet solvent extraction or ultrasound/solvent extraction of manually processed shells at ambient temperature gave similar yields and economy in solvent usage. Both were much superior to mechanical agitation. By catalyzed decarboxylation of the recovered natural CNSL an almost theoretical yield (25%) of phenolic lipid rich in cardanol was obtained, which is considerably higher than that (10%) in the traditional recovery of technical CNSL by the hot oil bath industrial method. Natural CNSL contains a predominant amount of anacardic acid and represents a novel phenolic lipid source. Chemical reduction with air/aqueous hydrazine gave saturated natural CNSL. Polymerization of natural CNSL was effected in alkaline solution with paraformaldehyde.
Hepatic cirrhosis, dystonia, polycythaemia and hypermanganesaemia—A new metabolic disorder
Authors: Tuschl Karin , Mills Philippa B. , Parsons Howard , Malone Marian , Fowler Darren , Bitner‐Glindzicz Maria , Clayton Peter T.
Published: April 2008

We report a new constellation of clinical features consisting of hypermanganesaemia, liver cirrhosis, an extrapyramidal motor disorder and polycythaemia in a 12 year‐old girl born to consanguineous parents. Blood manganese levels were >3000 nmol/L (normal range <320 nmol/L) and MRI revealed signal abnormalities of the basal ganglia consistent with manganese deposition. An older brother with the same phenotype died at 18 years, suggesting a potentially lethal, autosomal recessive disease. This disorder is probably caused by a defect of manganese metabolism with the accumulation of manganese in the liver and the basal ganglia similar to the copper accumulation in Wilson disease. In order to assess the genetic basis of this syndrome we investigated two candidate genes: ATP2C2 and ATP2A3 encoding the manganese‐transporting calcium‐ATPases, SPCA2 and SERCA3, respectively. Genotyping of the patient and the family for microsatellite markers surrounding ATP2C2 and ATP2A3 excluded these genes. The patient was found to be heterozygous for both gene loci. Despite the unknown pathophysiology, we were able to develop a successful treatment regime. Chelation therapy with disodium calcium edetate combined with iron supplementation is the treatment of choice, lowering blood manganese levels significantly and improving clinical symptoms.
AGAT, GAMT and SLC6A8 distribution in the central nervous system, in relation to creatine deficiency syndromes: A review
Authors: Braissant O. , Henry H.
Published: April 2008

Creatine deficiency syndromes, either due to AGAT, GAMT or SLC6A8 deficiencies, lead to a complete absence, or a very strong decrease, of creatine within the brain, as measured by magnetic resonance spectroscopy. While the mammalian central nervous system (CNS) expresses AGAT, GAMT and SLC6A8, the lack of SLC6A8 in astrocytes around the blood–brain barrier limits the brain capacity to import creatine from the periphery, and suggests that the CNS has to rely mainly on endogenous creatine synthesis through AGAT and GAMT expression. This seems contradictory with SLC6A8 deficiency, which, despite AGAT and GAMT expression, also leads to creatine deficiency in the CNS. We present novel data showing that in cortical grey matter, AGAT and GAMT are expressed in a dissociated way: e.g. only a few cells co‐express both genes. This suggests that to allow synthesis of creatine within the CNS, at least for a significant part of it, guanidinoacetate must be transported from AGAT‐ to GAMT‐expressing cells, possibly through SLC6A8. This would explain the creatine deficiency observed in SLC6A8‐deficient patients. By bringing together creatine deficiency syndromes, AGAT, GAMT and SLC6A8 distribution in CNS, as well as a synthetic view on creatine and guanidinoacetate levels in the brain, this review presents a comprehensive framework, including new hypotheses, on brain creatine metabolism and transport, both in normal conditions and in case of creatine deficiency.
Reduction in bone mineral density in glycogenosis type III may be due to a mixed muscle and bone deficit
Authors: Mundy H. R. , Williams J. E. , Lee P. J. , Fewtrell M. S.
Published: April 2008

Glycogen storage disease type III (GSD III; OMIM 232400) is an autosomal recessive deficiency of the glycogen debrancher enzyme, amylo‐1,6‐glucosidase (EC 3.2.1.33). Patients with other hepatic glycogenoses are known to have reduced bone mineral content (BMC) and to be at consequent risk of fractures. They have key metabolic differences from GSD III patients, however. This study examines bone density and metabolism in 15 GSD III patients (6 female) from childhood to adulthood (aged 10–34 years). The results demonstrate that patients with GSD III have low bone mass at all skeletal sites compared with healthy individuals of the same age and sex, with a significant proportion (40–64%) having BMD > 2 standard deviations below the mean for whole body and lumbar spine. The deficiency seems to be attributable to a mixed muscle andbone deficit. Lower bone mass was found at all sites for GSD IIIa patients (combined liver and muscle defect) compared with GSD IIIb patients (liver only defect). Conclusion: Patients with GSD III have significantly abnormal bone mass, placing them at increased risk of potential fracture. The underlying mechanism is probably multifactorial with contributions from abnormal muscle physiology, abnormal metabolic milieu and altered nutrition affecting micronutrient intake. Therapies need to address all these factors to be successful.
Sanfilippo syndrome: A mini‐review
Authors: Valstar M. J. , Ruijter G. J. G. , van Diggelen O. P. , Poorthuis B. J. , Wijburg F. A.
Published: April 2008

Mucopolysaccharidosis type III (MPS III, Sanfilippo syndrome) is an autosomal recessive disorder, caused by a deficiency in one of the four enzymes involved in the lysosomal degradation of the glycosaminoglycan heparan sulfate. Based on the enzyme deficiency, four different subtypes, MPS IIIA, B, C, and D, are recognized. The genes encoding these four enzymes have been characterized and various mutations have been reported. The probable diagnosis of all MPS III subtypes is based on increased concentration of heparan sulfate in the urine. Enzymatic assays in leukocytes and/or fibroblasts confirm the diagnosis and allow for discrimination between the different subtypes of the disease. The clinical course of MPS III can be divided into three phases. In the first phase, which usually starts between 1 and 4 years of age, a developmental delay becomes apparent after an initial normal development during the first 1–2 years of life. The second phase generally starts around 3–4 years and is characterized by severe behavioural problems and progressive mental deterioration ultimately leading to severe dementia. In the third and final stage, behavioural problems slowly disappear, but motor retardation with swallowing difficulties and spasticity emerge. Patients usually die at the end of the second or beginning of the third decade of life, although survival into the fourth decade has been reported. Although currently no effective therapy is yet available for MPS III, several promising developments raise hope that therapeutic interventions, halting the devastating mental and behavioural deterioration, might be feasible in the near future.
N‐3 Polyunsaturated Fatty Acids Modulate In‐Vitro T Cell Function in Type I Diabetic Patients
Authors: Merzouk Sid Ahmed , Saker Meriem , Reguig Karima Briksi , Soulimane Nassima , Merzouk Hafida , Guermouche Baya , Berrouiguet Abdelsslam Yahia , Hichami Aziz , Narce Michel , Khan Naim Akhtar
Published: April 2008

In this work, we assessed the in‐vitro effects of eicosapentaenoic acid (EPA; C20:5n‐3) and docosahexaenoic acid (DHA; C22:6n‐3) (final concentration, 15 μM) on T cell blastogenesis, interleukin‐2 and ‐4 (IL‐2, IL‐4) secretion, fatty acid composition and intracellular oxidative status in type I diabetic patients with or without complications. Con A stimulated lymphocyte proliferation, glucose uptake, intracellular reduced glutathione levels and catalase activity were lower in diabetics as compared to controls, regardless to the presence of complications. EPA and DHA diminished T‐lymphocyte proliferation and IL‐2 production but enhanced IL‐4 secretion in both diabetic and control groups. No changes in the levels of reduced glutathione and in the activities of catalase and SOD were observed in control T cells cultured in the presence of EPA and DHA. However, in diabetic patients, addition of n‐3 PUFA to culture induced an increase in T cell levels of reduced glutathione and hydroperoxide, and in activities of catalase and SOD. Low levels of arachidonic acid (C20:4n‐6) were found in plasma membrane phospholipids of lymphocytes from diabetic patients compared to controls. Incubation of lymphocytes with EPA and DHA was associated with an incorporation of these fatty acids in membrane phospholipids. In conclusion, the beneficial effects of n‐3 PUFA on T cell functions in type I diabetes could be attributed to their suppressive action and modulation of cytokine secretion, and to the improvement of intracellular oxidative status.
Norm convergence of multiple ergodic averages for commuting transformations
Authors: TAO TERENCE
Published: April 2008

Let T1,…,Tl:X→X be commuting measure-preserving transformations on a probability space $(X, \mathcal {X}, \mu )$. We show that the multiple ergodic averages $\bfrac {1}{N} \sum _{n=0}^{N-1} f_1(T_1^n x) \cdots f_l(T_l^n x)$ are convergent in $L^2(X,\mathcal {X},\mu )$ as $N \to \infty $ for all $f_1,\ldots ,f_l \in L^\infty (X,\mathcal {X},\mu )$; this was previously established for l=2 by Conze and Lesigne [J. P. Conze and E. Lesigne. Théorèmes ergodique por les mesures diagonales. Bull. Soc. Math. France112 (1984), 143–175] and for general l assuming some additional ergodicity hypotheses on the maps Ti and TiTj−1 by Frantzikinakis and Kra [N. Frantzikinakis and B. Kra. Convergence of multiple ergodic averages for some commuting transformations. Ergod. Th. & Dynam. Sys.25 (2005), 799–809] (with the l=3 case of this result established earlier by Zhang [Q. Zhang. On the convergence of the averages $\bfrac {1}{N} \sum _{n=1}^N f_1(R^n x) f_2(S^n x) f_3(T^n x)$. Mh. Math.122 (1996), 275–300]). Our approach is combinatorial and finitary in nature, inspired by recent developments regarding the hypergraph regularity and removal lemmas, although we will not need the full strength of those lemmas. In particular, the l=2 case of our arguments is a finitary analogue of those by Conze and Lesigne.
Product platform design and customization: Status and promise
Authors: SIMPSON TIMOTHY W.
Published: April 2008

In an effort to improve customization for today's highly competitive global marketplace, many companies are utilizing product families and platform-based product development to increase variety, shorten lead times, and reduce costs. The key to a successful product family is the product platform from which it is derived either by adding, removing, or substituting one or more modules to the platform or by scaling the platform in one or more dimensions to target specific market niches. This nascent field of engineering design has matured rapidly in the past decade, and this paper provides a comprehensive review of the flurry of research activity that has occurred during that time to facilitate product family design and platform-based product development for mass customization. Techniques for identifying platform leveraging strategies within a product family are reviewed along with metrics for assessing the effectiveness of product platforms and product families. Special emphasis is placed on optimization approaches and artificial intelligence techniques to assist in the process of product family design and platform-based product development. Web-based systems for product platform customization are also discussed. Examples from both industry and academia are presented throughout the paper to highlight the benefits of product families and product platforms. The paper concludes with a discussion of potential areas of research to help bridge the gap between planning and managing families of products and designing and manufacturing them.
Complex products and systems: Potential from using layout platforms
Authors: HOFER ADRIAN P. , HALMAN JOHANNES I.M.
Published: April 2008

In their quest to manage the complexity of offering greater product variety, firms in many industries are considering platform-based development of product families. Key in this approach is the sharing of components, modules, and other assets across a family of products. Current research indicates that companies are often choosingphysicalelements of the product architecture (i.e., components, modules, building blocks) for building platform-based product families. Other sources for platform potential are widely neglected. We argue that for complex products and systems with hierarchic product architectures and considerable freedom in design, a new platform type, thesystem layout, offers important commonality potential. This layout platform standardizes the arrangement of subsystems within the product family. This paper is based on three industry case studies, where a product family based on a common layout could be defined. In combination with segment-specific variety restrictions, this results in an effective, efficient, and flexible positioning of a company's products. The employment of layout platforms leads to substantial complexity reduction, and is the basis for competitive advantage, as it imposes a dominant design on a product family, improves its configurability, and supports effective market segmentation.
Boltzmann bias grand canonical Monte Carlo
Authors: Garberoglio G.
Published: April 2008

We derive an efficient method for the insertion of structured particles in grand canonical Monte Carlo simulations of adsorption in very confining geometries. We extend this method to path integral simulations and use it to calculate the isotherm of adsorption of hydrogen isotopes in narrow carbon nanotubes (two-dimensional confinement) and slit pores (one-dimensional confinement) at the temperatures of 20 and 77 K, discussing its efficiency by comparison to the standard path integral grand canonical Monte Carlo algorithm. We use this algorithm to perform multicomponent simulations in order to calculate the hydrogen isotope selectivity for adsorption in narrow carbon nanotubes and slit pores at finite pressures. The algorithm described here can be applied to the study of adsorption of real oligomers and polymers in narrow pores and channels.
Rotational-vibrational energy spectra of triatomic molecules near relative equilibria
Authors: Iwai Toshihiro , Yamaoka Hidetaka
Published: April 2008

Complete Hamiltonian operators have been obtained in terms of internal coordinates on the basis of the fiber bundle theory in geometry [J. Math Phys. 44, 4411 (2003)]. In this article, the full Hamiltonian is specialized for a rigid and for a semirigid molecule. For the rigid molecule, all internal coordinates are fixed at constants, so that the Hamiltonian operator comes to take an ordinary matrix form, and accordingly, the Schrödinger equation becomes an algebraic eigenvalue equation. The eigenvalues then provide rotational energy spectra of the rigid molecule. For the semirigid molecule, the full Hamiltonian is expanded in the vicinity of an equilibrium position into a power series in an infinitesimal parameter, to which the perturbation method is applied to obtain energy spectra in the form of a power series in the infinitesimal parameter. Indeed, the energy spectra are calculated to the second order term in the infinitesimal parameter in both the cases where the unperturbed energy spectra are nondegenerate and where those are degenerate. It then turns out that the amount of the energy shift caused by the rotation, which is the sum of the pure rotational and the rotation-vibration coupling terms, is proportional to the total angular momentum eigenvalue. It is also observed that a vibrational energy shift occurs simultaneously, which is caused by the metric defined on the internal space. No symmetry is assumed on the shape of the molecule in equilibrium.
Optical energies of AlInN epilayers
Authors: Wang K. , Martin R. W. , Amabile D. , Edwards P. R. , Hernandez S. , Nogales E. , O’Donnell K. P. , Lorenz K. , Alves E. , Matias V. , Vantomme A. , Wolverson D. , Watson I. M.
Published: April 2008

Optical energy gaps are measured for high-quality Al1−xInxN-on-GaN epilayers with a range of compositions around the lattice match point using photoluminescence and photoluminescence excitation spectroscopy. These data are combined with structural data to determine the compositional dependence of emission and absorption energies. The trend indicates a very large bowing parameter of ≈6eV and differences with earlier reports are discussed. Very large Stokes’ shifts of 0.4–0.8eV are observed in the composition range 0.13<x<0.24, increasing approximately linearly with InN fraction despite the change of sign of the piezoelectric field.
Impact of defects on the properties of ferromagnetic nanoparticles
Authors: Wesselinowa J. M. , Apostolova I.
Published: April 2008

The influence of doping effects on different static properties of spherical ferromagnetic nanoparticles is studied based on the Heisenberg model and by using the Green function technique. The obtained results show that the properties can increase or decrease for different kinds and numbers of doping ions. Moreover, the filling with defects beginning from the surface shell leads to a stronger increase or decrease of the magnetization, the Curie temperature, and the coercive field with an increasing number of defect shells compared to the case of filling with defects beginning from the central atom. The results are in accordance with the experimental data.