bluuebunny/crossref_metadata_2025 huggingface dataset:
High stakes
Authors: Elgin Catherine Z.
Published: October 2004

I discuss the contributions of Harvey Siegel, Francis Schrag and Randall Curren to this volume. Their articles cast in bold relief the relation of High Stakes Testing to the goals of education, the nature of mind and the demands of justice. I argue that the connections are deep, but that the considerations these authors raise do not show that High Stakes Tests are in principle unacceptable. Rather, they show that we need to be exceedingly careful about how our assessments are constructed, how the results are interpreted, what we take them to reveal and what we do with the results.
The morality of school choice reconsidered
Authors: Swift Adam
Published: October 2004

I reply to the more philosophical critiques of How Not to Be a Hypocrite (2003), published in this volume of Theory and Research in Education. Against Elizabeth Anderson, I claim that unequal chances are unfair, and unfairness is bad, but acknowledge that its badness can be outweighed by other values. Distinguishing principled from empirical disagreements, I argue that even where rules permitting private schools are justified on productivity grounds, we should still consider those rules to be unfair, and parents who use them to favour their own children to be exceeding the bounds of legitimate partiality. I agree with much of Matthew Clayton’s and David Stevens’ discussion of the burdens of injustice, but suggest that they underestimate the weight of partial reasons, a weight which may be acknowledged even from the impersonal standpoint. Sympathetic to Colin Macleod’s discussion of partiality-constituted goods, I doubt that school choice qualifies as something the personal monitoring of which destroys spontaneity, and offer other reasons why it is worse not to vote for abolition than to send one’s child to a private school. I end by distinguishing two ways in which the current choice situation facing affluent parents may be unjust, and explain why Hypocrite took a strategic decision to leave that distinction unbroached.
The problem with faith schools
Authors: Hand Michael
Published: October 2004

Geoffrey Short, Harvey Siegel and Douglas Groothuis have, in previous issues, advanced a number of objections to my recent paper (Vol. 1(1)) arguing for the abolition of faith schools. Here I attempt to answer their criticisms.
A Simple Alternative to Ethylene Vinyl Acetate Copolymers (EVAS) for Produce and Packaging Films
Authors: Hitchcock Amy B.
Published: October 2004

Ethylene vinyl acetate copolymers (EVAs) have historically been used to provide seal strength and good gloss in packaging for carrots, lettuce, and grapes. It is possible to obtain the same optical properties and increased sealing properties through the use of clarity and enhanced clarity linear low-density polyethylenes (LLDPEs). Several coextruded structures containing these two improved LLDPEs were selected to provide more economical options to the film converter. Data were obtained on these coextruded structures, comparing their properties to typical EVA coextrusions.
Metallocene LLDPE Films for Heavy-Duty Sack Applications
Authors: Fiscus David M.
Published: October 2004

This article describes (1) the applications for heavy-duty sacks, (2) the technical requirements for the sacks, and (3) the films and resins used to meet the critical requirements for this industry. It also describes how the technical requirements of the sack are determined. Finally, it shows how gas phase metallocene-catalyzed hexene copolymer linear low density polyethylene resins are used to produce downgauged sacks with tailored properties to meet the needs of this industry.
Blockade of Platelet-Derived Growth Factor Receptor-Beta by CDP860, a Humanized, PEGylated di-Fab', Leads to Fluid Accumulation and Is Associated With Increased Tumor Vascularized Volume
Authors: Jayson G.C. , Parker G.J.M. , Mullamitha S. , Valle J.W. , Saunders M. , Broughton L. , Lawrance J. , Carrington B. , Roberts C. , Issa B. , Buckley D.L. , Cheung S. , Davies K. , Watson Y. , Zinkewich-Péotti K. , Rolfe L. , Jackson A.
Published: October 2004

Purpose

CDP860 is an engineered Fab' fragment-polyethylene glycol conjugate, which binds to and blocks the activity of the beta-subunit of the platelet-derived growth factor receptor (PDGFR-β). Studies in animals have suggested that PDGFR-β inhibition reduces tumor interstitial fluid pressure, and thus increases the uptake of concomitantly administered drugs. The purpose of this study was to determine whether changes in tumor vascular parameters could be detected in humans, and to assess whether CDP860 would be likely to increase the uptake of a concurrently administered small molecule in future studies.

Patients and Methods

Patients with advanced ovarian or colorectal cancer and good performance status received intravenous infusions of CDP860 on days 0 and 28. Patients had serial dynamic contrast-enhanced magnetic resonance imaging studies to measure changes in tumor vascular parameters.

Results

Three of eight patients developed significant ascites, and seven of eight showed evidence of fluid retention. In some patients, the ratio of vascular volume to total tumor volume increased significantly (P < .001) within 24 hours following CDP860 administration, an effect suggestive of recruitment of previously non-functioning vessels.

Conclusion

These observations suggest that inhibition of PDGFR-β might improve delivery of a concurrently administered therapy. However, in cancer patients, further exploration of the dosing regimen of CDP860 is required to dissociate adverse effects from beneficial effects. The findings challenge the view that inhibition of PDGF alone is beneficial, and confirm that effects of PDGFR kinase inhibition mediate, to some extent, the fluid retention observed in patients treated with mixed tyrosine kinase inhibitors.
ZrCl4 as an Efficient Catalyst for Selective Tosylation of Alcohols with p-Toluenesulfonic Acid
Authors: Das Biswanath , Reddy Vtukuri Saidi
Published: October 2004

Tosylation of alcohols has directly been carried out with p-toluenesulfonic acid in methylene chloride under reflux using ZrCl4 as a catalyst. Primary alcohols were found to be tosylated chemoselectively over secondary alcohols.
Functional Characterization of Atherosclerosis-Associated Ser128Arg and Leu554Phe E-Selectin Mutations
Authors: Wenzel K. , Stahn R. , Speer A. , Denner K. , Gläser C. , Affeldt M. , Moobed M. , Scheer A. , Baumann G. , Felix S.B.
Published: October 2004

The cellular adhesion molecule E-selectin is expressed on activated endothelial cells, and is involved in the process of adherence of blood cells to vessel endothelium in inflammatory events such as atherosclerosis. In a recent study we found a Ser128Arg mutation in the EGF domain as well as a Leu554Phe mutation in the membrane domain of E-selectin. We also established increased frequencies of both mutations among young patients with severe coronary atherosclerosis. In the present study we investigated the influence of these mutations on cell adhesion and on the release of soluble E-selectin. Mutants were created by site-directed mutagenesis and COS cells were transfected with E-selectin, either wild-type or mutant. Antibody-binding studies and cell-adhesion assays were performed on transfected COS cells and on interleukin-1 beta-stimulated HUVECs. Soluble E-selectin in supernatants of wild type and Leu554Phe mutant-transfected COS cells was measured by ELISA. We discovered significant differences in the strength of HL-60 cell adhesion for the Ser128Arg mutant: in comparison with the wild type, the strength of adhesion to the mutant was reduced on transfected COS cells (P < 0.01) as well as on stimulated HUVECs (P < 0.01). Significantly diminished release of soluble E-selectin was detected for the Leu554Phe membrane domain mutant, in comparison with the wild type. In summary, the mutations studied here influence the E-selectin functionin vitroand may be considered as one of the risk factors involved in the complex pathogenesis of atherosclerosis.
Cycloheximide, a New Tool to Dissect Specific Steps in ER-Associated Degradation of Different Substrates
Authors: Amshoff C. , Jäck H.-M. , Haas I.G.
Published: October 2004

To study the degradation requirements of unassembled immunoglobulin (Ig) chains, we heterologously expressed a cDNA encoding the secretory form of murine μ in the yeast
Localization of Rat Cathepsin K in Osteoclasts and Resorption Pits: Inhibition of Bone Resorption and Cathepsin K-Activity by Peptidyl Vinyl Sulfones
Authors: Xia L. , Kilb J. , Wex H. , Li Z. , Lipyansky A. , Breuil V. , Stein L. , Palmer J.T. , Dempster D.W. , Brömme D.
Published: October 2004

We have localized cathepsin K in rat osteoclasts and within exposed resorption pits by immuno-fluorescence microscopy. Intracellular staining using an antibody raised against recombinant mouse cathepsin K was vesicular and uniformly distributed throughout the cell. Confocal microscopy analysis did not reveal an accumulation of cathepsin K containing vesicles opposing the ruffled border and the resorption lacuna. Exposed resorption pits exhibited a uniform distribution of cathepsin K, and no differences were observed between the edges and the centers of the pits. The immunostaining of resorption pits with anti-cathepsin K antibodies demonstrates that the protease is secreted into the sub-osteoclastic compartment.

Cathepsin K-specific inhibition using peptidyl vinyl sulfones as selective cysteine protease inactivators reduced bone resorption by 80% in a dose-dependent manner at sub-micromolar concentrations. No reduction of bone resorption was observed at those low concentrations using a potent cathepsin L, S, B-specific inhibitor. That the inhibition of bone resorption can be attributed to cathepsin K-like protease inhibition was corroborated by the selective inhibition of the osteoclastic Z-Gly-Pro-Arg-MβNA hydrolyzing activity by the cathepsin K, L, S, B-inhibitor, but not by the cathepsin L, B, and S inhibitor. Z-Gly-Pro-Arg-MβNA is efficiently hydrolyzed by cathepsin K but only poorly by cathepsins L, S, and B. On the contrary, the intracellular hydrolysis of the cathepsin B-specific substrate, Z-Arg-Arg-MβNA, was prevented by both types of inhibitors.

The identification of cathepsin K in resorption pits and the inhibition of bone resorption and intracellular cathepsin K activity by selective vinyl sulfone inhibitors indicate the critical role of the protease in osteoclastic bone resorption.
Oxidation of 4-tert-Butylcatechol and Dopamine by Hydrogen Peroxide Catalysed by Horseradisch Peroxidase
Authors: García-Moreno M. , Moreno-Conesa M. , Rodríguez-López J.N. , García-Cánovas F. , Varón R.
Published: October 2004

The catalytic cycle of horseradish peroxidase (HRP; donor:hydrogen peroxide oxidoreductase; EC 1.11.1.7) is initiated by a rapid oxidation of it by hydrogen peroxide to give an enzyme intermediate, compound I, which reverts to the resting state via two successive single electron transfer reactions from reducing substrate molecules, the first yielding a second enzyme intermediate, compound II. To investigate the mechanism of action of horseradish peroxidase on catechol substrates we have studied the oxidation of both 4-
Acquisition of Myogenic Specificity through Replacement of One Amino Acid of MASH-1 and Introduction of an Additional alpha -Helical Turn
Authors: Dezan C. , Meierhans D. , Künne A.G.E. , Allemann R.K.
Published: October 2004

The homologous transcription factors Myf-5, MyoD, myogenin, MRF-4, and MASH-1 bind with high affinity and modest sequence specificity to DNA containing an E-box (CANNTG). This similarity of the
The Heavy Metal-Responsive Transcription Factor-1 (MTF-1) Is Not Required for Neural Differentiation
Authors: Lichtlen P. , Georgiev O. , Schaffner W. , Aguzzi A. , Brandner S.
Published: October 2004

The zinc finger transcription factor MTF-1 is essential for proper response to heavy metal load and other stress conditions in vertebrates, and also contributes to the maintenance of the cellular redox state. Target genes include metallothioneins (MT-I and MT-II) and gamma-glutamylcysteine synthetase (gamma-GCS), an enzyme involved in glutathione biosynthesis. Although MTF-1 is expressed ubiquitously, the primary defect in null mutant mice is hepatocyte necrosis, which results in embryonic lethality around day E14 and prevents the analysis of delayed effects on other organs. To assess the impact of MTF-1 deficiency on the function of the mature central nervous system, we employed the neural grafting strategy. Neuroectodermal brain tissue obtained from transgenic mouse embryos at gestational day 12.5 was transplanted into the caudoputamen of adult wild-type mice. 33 days later, grafts derived from MTF-1 deficient mice consisted of fully differentiated neuroectodermal tissue and showed no differences to heterozygous control grafts. This indicates that MTF-1 is dispensable for the development and differentiation of the nervous system. Such transplants devoid of MTF-1 may provide a useful tool for the further investigation of the effect of cell stress, including oxidative stress.
Universal and Unique Features of Kinesin Motors: Insights from a Comparison of Fungal and Animal Conventional Kinesins
Authors: Kirchner J. , Woehlke G. , Schliwa M.
Published: October 2004

Kinesins are microtubule motors that use the energy derived from the hydrolysis of ATP to move unidirectionally along microtubules. The founding member of this still growing superfamily is conventional kinesin, a dimeric motor that moves processively towards the plus end of microtubules. Within the family of conventional kinesins, two groups can be distinguished to date, one derived from animal species, and one originating from filamentous fungi. So far no conventional kinesin has been reported from plant cells. Fungal and animal conventional kinesins differ in several respects, both in terms of their primary sequence and their physiological properties. Thus all fungal conventional kinesins move at velocities that are 4–5 times higher than those of animal conventional kinesins, and all of them appear to lack associated light chains. Both groups of motors are characterized by a number of group-specific sequence features which are considered here with respect to their functional importance. Animal and fungal conventional kinesins also share a number of sequence characteristics which point to common principles of motor function. The overall domain organization is remarkably similar. A C-terminal sequence motif common to all kinesins, which constitutes the only region of high homology outside the motor domain, suggests common principles of cargo association in both groups of motors. Consideration of the differences of, and similarities between, fungal and animal kinesins offers novel possibilities for experimentation (e. g., by constructing chimeras) that can be expected to contribute to our understanding of motor function.
On the Lysosomal Degradation of Neurofibromin and Its Phosphorylation in Cultured Melanocytes
Authors: Kaufmann Dieter , Junge Iska , Bartelt Britta , Lattke Herbert , Müller Ralf
Published: October 2004

Neurofibromatosis type 1 (NF1) is one of the most
common inherited disorders in humans. Most of the
NF1gene mutations result in a reduction of the amount
of neurofibromin to about 50%. Recently, we found
that the level of neurofibromin can be regulated posttranslationally
through the alteration of its half-life.
Here, we investigated whether lysosomes are involved
in this post-translational regulation in cultured melanocytes
of NF1 patients and controls. When the lysosomal
degradation was inhibited by chloroquine, an
increase of neurofibromin by a factor of 2 to 3, correlating
with an increased half-life, was measured. Incubation
with phosphoprotein-phosphatase inhibitors
also increased the neurofibromin content in melanocytes.
Investigations on phosphorylation of neurofibromin
revealed a basal phosphorylation in melanocytes
cultured with growth factor-deprived medium
that increased upon incubation with the growth stimulators
PMA or bFGF. Because both factors are also
able to increase the half-life of neurofibromin, we suggest
its phosphorylation to be an important step in
protecting neurofibromin against specific lysosomal
degradation.
Isolation and Characterization of Viridin, a New 65 kDa Antifungal Protein from the Mould Trichoderma viride
Authors: Hao Jian-Jiang , Geng Chuan-dong , Xie Wei-jun , Gong Zhen-zhen , Liu Wang-Yi , Wang En-duo
Published: October 2004

A new extracellular antifungal protein with a yield of 10 mg per liter was isolated from the culture medium of the mouldTrichoderma viride. The protein, which we named viridin, was purified by carboxymethyl-cellulose cation-exchange chromatography and Superose 12 HR 10/30 high-performance liquid chromatography. Viridin, a basic protein of approximately 65 kDa as determined by SDS-PAGE, inhibits the growth of the cotton pathogenVerticillum dahliae, the IC50being 6 ΜM.
An Evaluation of Techniques for the Extraction and Amplification of DNA from Naturally Shed Hairs
Authors: Vigilant Linda
Published: October 2004

Hair can be a valuable source of DNA for the noninvasive study of human and nonhuman populations. However, hairs contain extremely small quantities of DNA, making the method used to extract the DNA of paramount importance. This study compares the effectiveness of 4 different methods of DNA extraction from shed chimpanzee hair, as measured by the ability to amplify mtDNA targets using PCR. The most successful method is also the simplest, requiring only digestion of the root end in a buffer compatible with subsequent PCR without a prior purification or extraction step. Strategies to non-specifically preamplify the template are not successful with DNA from stored shed hairs.
Huntington's disease–like 2 (HDL2) in North America and Japan
Authors: Margolis Russell L. , Holmes Susan E. , Rosenblatt Adam , Gourley Lisa , O'Hearn Elizabeth , Ross Christopher A. , Seltzer William K. , Walker Ruth H. , Ashizawa Tetsuo , Rasmussen Astrid , Hayden Michael , Almqvist Elisabeth W. , Harris Juliette , Fahn Stanley , MacDonald Marcy E. , Mysore Jayalakshmi , Shimohata Takayoshi , Tsuji Shoji , Potter Nicholas , Nakaso Kazuhiro , Adachi Yoshiki , Nakashima Kenji , Bird Thomas , Krause Amanda , Greenstein Penny
Published: October 2004

Huntington's Disease–like 2 (HDL2) is a progressive, autosomal dominant, neurodegenerative disorder with marked clinical and pathological similarities to Huntington's disease (HD). The causal mutation is a CTG/CAG expansion mutation on chromosome 16q24.3, in a variably spliced exon of junctophilin‐3. The frequency of HDL2 was determined in nine independent series of patients referred for HD testing or selected for the presence of an HD‐like phenotype in North America or Japan. The repeat length, ancestry, and age of onset of all North American HDL2 cases were determined. The results show that HDL2 is very rare, with a frequency of 0 to 15% among patients in the nine case series with an HD‐like presentation who do not have the HD mutation. HDL2 is predominantly, and perhaps exclusively, found in individuals of African ancestry. Repeat expansions ranged from 44 to 57 triplets, with length instability in maternal transmission detected in a repeat of 33 triplets. A younger age of onset is correlated with a longer repeat length (r2 = 0.29, p = 0.0098). The results further support the evidence that the repeat expansion at the chromosome 16q24.3 locus is the direct cause of HDL2 and provide preliminary guidelines for the genetic testing of patients with an HD‐like phenotype. Ann Neurol 2004

An Erratum has been published for this article in Ann Neurol 56: 911, 2004.
Minocycline prevents cholinergic loss in a mouse model of Down's syndrome
Authors: Hunter Christopher L. , Bachman David , Granholm Ann‐Charlotte
Published: October 2004

Individuals with Down's syndrome develop Alzheimer's‐like pathologies comparatively early in life, including progressive degeneration of basal forebrain cholinergic neurons (BFCNs). Cholinergic hypofunction contributes to dementia‐related cognitive decline and remains a target of therapeutic intervention for Alzheimer's disease. In light of this, partial trisomy 16 (Ts65Dn) mice have been developed to provide an animal model of Down's syndrome that exhibits progressive loss of BFCNs and cognitive ability. Another feature common to both Down's syndrome and Alzheimer's disease is neuroinflammation, which may exacerbate neurodegeneration, including cholinergic loss. Minocycline is a semisynthetic tetracycline with antiinflammatory properties that has demonstrated neuroprotective properties in certain disease models. Consistent with a role for inflammatory processes in BFCN degeneration, we have shown previously that minocycline protects BFCNs and improves memory in mice with acute, immunotoxic BFCN lesions. We now report that minocycline treatment inhibits microglial activation, prevents progressive BFCN decline, and markedly improves performance of Ts65Dn mice on a working and reference memory task. Minocycline is an established antiinflammatory and neuroprotective drug and may provide a novel approach to treat specific AD‐like pathologies. Ann Neurol 2004
Actin mutations are one cause of congenital fibre type disproportion
Authors: Laing Nigel G. , Clarke Nigel F. , Dye Danielle E. , Liyanage Khema , Walker Kendall R. , Kobayashi Yasuaki , Shimakawa Shuichi , Hagiwara Tohru , Ouvrier Robert , Sparrow John C. , Nishino Ichizo , North Kathryn N. , Nonaka Ikuya
Published: October 2004

We report three heterozygous missense mutations of the skeletal muscle alpha actin gene (ACTA1) in three unrelated cases of congenital fiber type disproportion (CFTD) from Japan and Australia. This represents the first genetic cause of CFTD to be identified and confirms that CFTD is genetically heterogeneous. The three mutations we have identified Leucine221Proline, Aspartate292Valine, and Proline332Serine are novel. They have not been found previously in any cases of nemaline, actin, intranuclear rod, or rod‐core myopathy caused by mutations in ACTA1. It remains unclear why these mutations cause type 1 fiber hypotrophy but no nemaline bodies. The three mutations all lie on one face of the actin monomer on the surface swept by tropomyosin during muscle activity, which may suggest a common pathological mechanism. All three CFTD cases with ACTA1 mutations had severe congenital weakness and respiratory failure without ophthalmoplegia. There were no clinical features specific to CFTD cases with ACTA1 mutations, but the presence of normal eye movements in a severe CFTD patient may be an important clue for the presence of a mutation in ACTA1. Ann Neurol 2004
Mechanical and thermal properties of glass bead–filled nylon‐6
Authors: Huang Li , Yuan Qiang , Jiang Wei , An Lijia , Jiang Shengxiang , Li R. K. Y.
Published: October 2004

The mechanical and thermal properties of glass bead–filled nylon‐6 were studied by dynamic mechanical analysis (DMA), tensile testing, Izod impact, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) tests. DMA results showed that the incorporation of glass beads could lead to a substantial increase of the glass‐transition temperature (Tg) of the blend, indicating that there existed strong interaction between glass beads and the nylon‐6 matrix. Results of further calculation revealed that the average interaction between glass beads and the nylon‐6 matrix deceased with increasing glass bead content as a result of the coalescence of glass beads. This conclusion was supported by SEM observations. Impact testing revealed that the notch Izod impact strength of nylon‐6/glass bead blends substantially decreased with increasing glass bead content. Moreover, static tensile measurements implied that the Young's modulus of the nylon‐6/glass bead blends increased considerably, whereas the tensile strength clearly decreased with increasing glass bead content. Finally, TGA and DSC measurements indicated that the thermal stability of the blend was obviously improved by incorporation of glass beads, whereas the melting behavior of the nylon‐6 remained relatively unchanged with increasing glass bead content. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1885–1890, 2004
Melt free‐radical grafting of maleimides with hindered phenol groups onto polyethylene
Authors: Kim Taek Hyeon
Published: October 2004

A monomeric antioxidant, bearing carbamate groups, was synthesized from the reaction of 3,5‐di‐tert‐butyl‐4‐hydroxybenzyl alcohol and azidomaleimide. Another antioxidant was prepared from the reaction of N‐(4‐hydroxyphenyl)maleimide and 3‐(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl) propionic chloride in the presence of triethylamine. These fictional antioxidants were grafted onto polyethylene (PE) via melt processing with free‐radical initiators in a minimax molder. The IR spectra of the grafted PE showed that the monomeric antioxidants were added to PE. IR spectroscopy methods were used for the quantitative determination of the extent of grafting of the monomeric antioxidants. Also, the extent of crosslinking was determined from the gel content. To optimize the reaction conditions, we investigated the effects of the initiator concentration, monomeric antioxidant, reaction time, and temperature on the extent of grafting. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2117–2122, 2004
Effect of rigid particle size on the toughness of filled polypropylene
Authors: Dubnikova I. L. , Berezina S. M. , Antonov A. V.
Published: October 2004

The role of rigid particle size in the deformation and fracture behavior of filled semicrystalline polymer was investigated with systems based on polypropylene (PP) and model rigid fillers [glass beads, Al(OH)3]. The regularities of the influence of particle content and size on the microdeformation mechanisms and fracture toughness of the composites at low and high loading rates were found. The existence of the optimal particle size for fixed filler content promoting both maximum ultimate elongation of the composite at the tensile and maximum toughness at impact test was shown. The decrease of the toughening effect with both decreasing and increasing particle size regarding the optimal one was explained by dual role of particle size, correspondingly as either “adhesive” or “geometric” factors of fracture. The adhesive factor is due by the increase of debonding stress with the particle size decrease and the voiding difficulty resulting in the restriction of plastic flow. The geometric factor consists in the dramatic decrease of the composite strength at break if the void size exceeds the critical size of defect (for a given matrix) at which the crack initiation occurs. The analysis of the filled polymer toughness dependencies upon the particle size revealed that a capacity of rigid particles for the energy dissipation at the high loading rate depends on two factors: (i) ability of the dispersed particles to detach from matrix and to initiate the matrix local shear yielding at the vicinity of the voids and (ii) the size of the voids forming. Based on the findings it was concluded that the optimal minimal rigid particle size for the polymer toughening should answer the two main requirements: (i) to be smaller than the size of defect dangerous for polymer fracture and (ii) to have low debonding stress (essentially lower compared to the polymer matrix yield stress). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1917–1926, 2004
Thermomechanical film properties and aging of blends of poly(lactic acid) and malonate oligomers
Authors: Ljungberg N. , Wesslén B.
Published: October 2004

Malonate oligomers were synthesized as plasticizers for poly(lactic acid) (PLA). Esterification reactions were performed between diethyl bishydroxymethyl malonate (DBM) and either adipoyl dichloride or succinyl dichloride. Two molar masses were obtained within each series. Blending was carried out with PLA and the four oligomers as well as the monomeric unit from the syntheses (DBM). Dynamic mechanical analysis and differential scanning calorimetry were used to investigate the viscoelastic mechanical and thermal film properties of the blends. All the investigated plasticizers reduced the glass‐transition temperature of PLA, and the plasticization effect was better for the plasticizers of low molar mass. However, the amorphous domains of PLA became saturated with plasticizer at a certain concentration, and phase separation occurred. A higher molar mass of the plasticizer caused this saturation to occur at lower plasticizer concentrations. Subsequently, the aging of the blends at the ambient temperature for 4 months induced phase separation in the blends containing DBM, whereas those with an oligomeric plasticizer were stable and remained compatible with PLA within the aging period. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2140–2149, 2004
Antimicrobial and physical properties of woolen fabrics cured with citric acid and chitosan
Authors: Hsieh S.‐H. , Huang Z. K. , Huang Z. Z. , Tseng Z. S.
Published: October 2004

In this study, we used citric acid (CA) as a crosslinking agent, mixed with biopolymer molecular chitosan, to perform a pad–dry–cure treatment on woolen fabrics to study its antimicrobial effects and physical properties with the help of IR spectroscopy, electron microscopy, and differential thermal analysis. From the experimental results, we learned that CA did not crosslink with the woolen fibers if the woolen fabrics were not oxidized by potassium permanganate and that after oxidization, CA produced esterification with the OH group of the wool and chitosan and transamidation with theNH2 group of the wool to form a crosslink. The surface crosslinks of the oxidized woolen fibers were relatively coarse, which is undesirable for shrink‐proofing and yet beneficial for the antimicrobial and antiseptic effects of the woolen fabrics. It had a negative effect on the fabric softness, yellowness, stretching resistance, and elongation percentage. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1999–2007, 2004
A one‐step method for fabricating chitosan microspheres
Authors: Kuo Shyh Ming , Niu Gregory Cheng‐Chie , Chang Shwu Jen , Kuo Chia Hung , Bair Miin Shyan
Published: October 2004

A simple and in situ method, by using a high‐voltage electrostatic system, for the fabrication of chitosan microspheres (in a form of isolatable microgels) by an extrusion process, exhibiting variable sizes and different membrane structures, was presented. The chitosan microspheres exhibited good sphericity and were in the range of 185.8 ± 13.8 to 380.9 ± 11.5 μm in diameter. There were two significant factors, the pump flow rate and electrostatic field strength, that affected the chitosan microsphere size. The microsphere size decreased when the flow rate was increased from 0.1 to 0.4 mL/h. Also, the microsphere size decreased when the electrostatic field strength was increased from 5.5 to 6.5 kV/cm. However, when the electrostatic field strength was raised to 7 kV/cm and higher, the microsphere size increased. For the latter case, with other parameters fixed, chitosan microsphere size can be controlled by adjusting the electrostatic field strength and predetermined by a simple linear regression equation: Microsphere Diameter (D, in μm) = −(75.48) + 45.67 × (Electrostatic Field Strength, E, in kV/cm), at [7 ≤ (Electrostatic Field Strength) ≤ 10] (R2 = 0.956, P < 0.001). Following treatment with various ratios of crosslinking/gelating (Na5P3O10/NaOH) agents, the prepared chitosan microspheres exhibited distinct membrane structures that yielded various mechanical strengths. In the Na5P3O10/NaOH ratio of 19, the chitosan microspheres had a distinct two‐layer structure. The selection of crosslinking/gelating ratio provided an additional degree of freedom, permitting the simultaneous regulation of mechanical properties and permeability of the microspheres, without extra manipulation, and thus, improved applicability in the biomedical field. When the chitosan microsphere extrusion process was used to encapsulate β‐tricalcium phosphate powder for application as bony material, we found that the ultra fine β‐tricalcium phosphate powder was trapped inside of the membrane very well. After appropriate collecting procedures, stored microspheres also retained good spherical shape. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2150–2157, 2004
Multifunctional coupling agents. II. Chain extension and terminal group modification of polyamides
Authors: Jakisch L. , Komber H. , Wursche R. , Böhme F.
Published: October 2004

New bifunctional coupling agents possessing one 2‐oxazoline group and one 2‐oxazinone group were converted in a Haake melt mixer or extruder with PA6 and PA12. It was shown by means of NMR spectroscopic investigations that the 2‐oxazoline group reacted mainly with carboxylic groups whereas the oxazinone group reacted preferably with the amino groups. Both reactions proceeded with high selectivity and independent from each other. In the case of carboxy/amino group terminated polyamides, the conversions resulted in increased molecular weights since both reactive terminal groups of the polyamides were addressed simultaneously by the coupling agent. In the case of amino group terminated polyamides, the conversion with the bifunctional coupling agent resulted in oxazoline terminated polymer chains. Unlike PA6, it was possible to convert PA12 in two steps. At lower temperatures (210°C) and short reaction times (2 min), the reaction of the oxazinone group with the amino groups was predominant, whereas the reaction of the oxazoline group with the carboxylic groups proceeded to a sufficient extent only after longer reaction times or at higher temperatures. In the case of PA6, processing temperatures of about 250°C were necessary. Here, a side reaction was observed that resulted in the formation of cyclic quinoxaline structures under evolution of water. This side reaction did not disturb the chain extension significantly. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2170–2177, 2004
Effect of CsBr–MnCl2 mixed fillers on the crystal structure and optical and electrical properties of poly(vinyl alcohol)
Authors: Abdelaziz M.
Published: October 2004

Poly(vinyl alcohol) (PVA) films filled with (x)CsBr(15 − x)MnCl2, where 0.0 ≤ x ≤ 15%, were prepared by a casting technique. The crystal structure properties of the prepared films were examined by XRD, DTA, and FTIR. A correlation between XRD, DTA, and FTIR of the filled polymer was discussed. Optical absorption measurements revealed two optical band gaps (Eg1 and Eg2). The electrical properties were studied using dc electrical conductivity. The filling level (FL) dependency of Eg1 and Eg2, thermal activation energy (ΔE), and hopping distance (R0) are given to illustrate the behavior of the filled polymers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2178–2186, 2004
The effect of fever, febrile illnesses, and heat exposures on the risk of neural tube defects in a Texas‐Mexico border population
Authors: Suarez Lucina , Felkner Marilyn , Hendricks Kate
Published: October 2004

BACKGROUND

Hyperthermia produces neural tube defects (NTDs) in a variety of animal species. Elevated maternal body temperatures may also place the developing human embryo at risk. We examined the relation between maternal hyperthermia and the development of NTDs in a high‐risk Mexican‐American population.

METHODS

Case‐women were Mexican‐American women with NTD‐affected pregnancies who resided and delivered in any of the 14 Texas counties bordering Mexico, during 1995–2000. Control‐women were randomly selected from study area residents delivering normal live births, frequency‐matched to cases by hospital and year. Information on maternal fevers, febrile illnesses, exposures to heat generated from external sources, and hyperthermia‐inducing activities was gathered through in‐person interviews, conducted about six weeks postpartum.

RESULTS

The risk effect (OR) associated with maternal fever in the first trimester, compared to no fever, was 2.9 (95% CI, 1.5–5.7). Women taking fever‐reducing medications showed a lower risk effect (OR, 2.4; 95% CI, 1.0–5.6) than those who did not (OR, 3.8; 95% CI, 1.4–10.9). First‐trimester maternal exposures to heat devices such as hot tubs, saunas, or electric blankets were associated with an OR of 3.6 (95% CI, 1.1–15.9). Small insignificant effects were observed for activities such as cooking in a hot kitchen (OR, 1.6; 95% CI, 1.0–2.6) and working or exercising in the sun (OR, 1.4; 95% CI, 0.9–2.2).

CONCLUSIONS

Maternal hyperthermia increases the risk for NTD‐affected offspring. Women intending to become pregnant should avoid intense heat exposures, carefully monitor and manage their febrile illnesses, and routinely consume folic acid supplements. Birth Defects Research (Part A), 2004. © 2004 Wiley‐Liss, Inc.
Design, synthesis, and evaluation of peptides with estrogen‐like activity
Authors: Kasher Roni , Gayer Batya , Kulik Tikva , Somjen Dalia , Venkatesh Natarajan , Fridkin Mati , Katchalski‐Katzir Ephraim , Kohen Fortune
Published: October 2004

Currently used antiestrogenic drugs against hormone‐dependent breast cancer, and estrogenic drugs used in treatment of osteoporosis, are associated with risk factors. Therefore, there is a strong need to develop selective estrogen receptor modulators with better tissue selectivity. In a recent study (Peptides, 2002, Vol. 3, 573–580), we used a monoclonal antibody to estradiol (mAb‐E2) to screen a phage‐display peptide library. We identified a 15‐mer peptide (peptide H5) that recognizes mAb‐E2 (IC50 1 μM) and estrogen receptor (ER)α (IC50 500 μM) but not ERβ, and displays estrogen‐like activity in vitro and in vivo. In this study, we designed and prepared peptides based on peptide H5, which possess improved estrogenic activity, by evaluating their binding to mAb‐E2 and to ERs. Initially, we determined the minimal binding sequence of peptide H5 capable of binding mAb‐E2 and ER. Subsequently, systematic single‐residue replacements of the minimal sequence, followed by multiple‐residue replacements, yielded hexa‐ and heptapeptides with increased affinities to mAb‐E2 and to ER. The most promising peptides, VSWFFE (EMP‐1) and VSWFFED (EMP‐2) (EMP: estrogen‐mimetic peptide), bind mAb‐E2 with high affinity (IC50 of 6 and 30 nM, respectively), recognize ERs with increased affinity (IC50 of 100 μM for ERα, and 100–250 μM for ERβ), and possess estrogenic activity in vivo. The short peptides described in this study may be used as potential lead compounds for developing new ER ligands. © 2004 Wiley Periodicals, Inc. Biopolymers (Pept Sci), 2004
Das Bioisosterie‐Konzept: Arzneistoffentwicklung
Authors: Siebert Carsten D.
Published: October 2004

Bioisosterie bedeutet gleiche räumliche Ausdehnung
bei vergleichbarer Wirkung in biologischen Systemen. Dies bezieht sich auf
pharmakologisch wirksame Verbindungen, die vor allem in vivo einen
vergleichbaren Effekt erzielen. Die Paare Benzol‐Thiophen, Benzol‐Pyridin und
Thiophen‐Furan sind bekannte Beispiele für Bioisosterie in der
Wirkstoffforschung.
Clemens Winkler – zum 100. Todestag
Authors: Volke Klaus
Published: October 2004

Clemens Winklers geniale analytische Fähigkeiten führten 1886 zur Entdeckung des Elementes Germanium. Damit konnte eine Lücke im Periodensystem der Elemente von Dmitrij Mendelejew (1834 – 1907) und Lothar Meyer (1830 – 1895) geschlossen werden.
Phasenumwandlung birgt Erinnerung
Authors: Feil Sylvia
Published: October 2004

Manche Stoffe scheinen ein Erinnerungsvermögen zu besitzen: Sie kehren unter Verrichtung mechanischer Arbeit in eine vorher eingeprägte Form zurück. Eine Legierung aus Nickel und Titan in nahezu stöchiometrischem Verhältnis – Nitinol – verfügt über ein solches Formgedächtnis. Dahinter steckt eine Festphasenumwandlung.
Museen und “Science Center” im Netz – reloaded
Authors: Hildebrandt Henry
Published: October 2004

Science Center sind “in” – Museen sind “out”. Allerdings: Wo eigentlich ist der Unterschied? Vielleicht sprechen neue Begriffe auch neue Zielgruppen an. Denn auch alte Museen haben schon immer mit ihren Ausstellungen zum aktiven Umgang aufgefordert – also: Alles nur geklaut?
Digital image interpolation with warping of coordinate point and biasing of signal amplitude
Authors: Shimura Atsushi , Taguchi Akira
Published: October 2004

Since the dimensions for digital images are set by the acquisition system, digital image enlargement is indispensable when the dimensions that can be displayed are larger in the display system than in the acquisition system. Conventionally, this enlargement process was performed by interpolation. The digital image enlargement corresponds to a larger Nyquist frequency, but the frequency band that is expanded during the enlargement cannot be considered by the interpolation scheme, and blur is produced in the enlarged image. The parts where the image blur stands out subjectively are primarily the signals forming the image contours having the step edge shape and the details of the image consisting of mountain‐ and valley‐shaped signals when viewed microscopically. Therefore, the proposed method moves the coordinate points interpolated to preserve the discontinuities of step edge signals and decides whether the interpolated points are the vertices of the mountain‐ or valley‐shaped signals, and then moves the amplitudes of the interpolated points for creating these peak signals up or down. In other words, we explain an interpolation scheme involving the warping and biasing that randomly moves the coordinate points and the signal amplitudes, and implement digital image interpolation with improved resolution. Furthermore, the parameter settings for the proposed method are both objectively and subjectively evaluated. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 88(2): 10–21, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20095
Reorganizing learning resources on the WWW and its application to adaptive recommendation for navigational support
Authors: Hasegawa Shinobu , Kashihara Akihiro , Toyoda Jun'ichi
Published: October 2004

As the Internet rapidly increases in popularity, learning resources on the WWW are being used more and more. Since there are many learning resources that describe the same topic from different perspectives on the WWW, it is possible to deepen understanding of topics by making good use of them. Though there exists a tremendous amount of learning resources, in many cases they do not have clear descriptions of their properties, such as “What you can learn and how.” Thus, it is very difficult for learners to select learning resources that match their objectives. As an approach to this issue, we propose a method of providing indexes for description of the properties of learning resources, and of reorganizing learning resources based on them. In order to show the usefulness of this reorganization, we have developed a resource navigation support method that recommends learning resources at each step, with the aim of helping learners to deepen their understanding of a certain subject of study step by step. Testing and evaluation have shown the validity of this navigation support method based on resource indexes. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 88(2): 52–63, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20158
Equal emissions per capita over time – a proposal to combine responsibility and equity of rights for post‐2012 GHG emission entitlement allocation
Authors: Bode Sven
Published: October 2004

Any effective future climate policy regime based on the Kyoto Protocol requires the determination of the concrete contribution regarding time and quantity for each party. Based on the two justice principles, responsibility and equity of rights, that form the basis for the so‐called Brazilian Proposal and Contraction and Convergence respectively, a new approach is developed: future emission rights are allocated on the basis of equal emissions per capita over time. By so doing not only are emissions per capita (EPC) taken into account during the allocation but also their evolution over time. This may result in negative quantities of emission rights for some parties due to their historical ‘burden’. On the other hand, parties with low EPC would be allocated large amounts of ‘fair air’. Even though this approach may currently lack political support by powerful parties, it offers another analytical reference point for the political bargaining process on future allocations. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment.
Expression of the SH2D1A gene is regulated by a combination of transcriptional and post‐transcriptional mechanisms
Authors: Okamoto Susumu , Ji Hongbin , Howie Duncan , Clarke Kareem , Gullo Charles , Manning Stephen , Coyle Anthony J. , Terhorst Cox
Published: October 2004

The SH2D1A gene, which is altered or deleted in patients with X‐linked lymphoproliferative disease, encodes the small protein SAP (for SLAM‐associated protein) that is expressed in T and NK cells. A 22‐bp fragment in close proximity to an initiator‐like site was defined as the basal promoter of mouse SH2D1A, and a highly homologous 33‐bp segment was defined as the human basal promoter. When an Ets consensus site was mutated, no reporter activity was detectable. Gel mobility supershift assays revealed that the two transcription factors Ets‐1 and Ets‐2 bind to the human and mouse sequences. The involvement of Ets‐1 and Ets‐2 in expression of SH2D1A was functionally confirmed by overexpression studies of their dominant‐negative forms. We also found that SH2D1A mRNA decays very rapidly in mouse T cells, and its 3′ untranslated region (UTR) has RNA‐destabilizing activity in transfection studies with reporter/3′ UTR constructs. As judged by RNA‐gel mobility shift assays, this rapid degradation of SH2D1A mRNA was due to a balance in binding of the factors AUF1 and HuR to its 3′ UTR. Although the SH2D1A mRNA level decreased upon triggering of the T cell receptor (TCR), the RNA degradation rate itself was not altered by TCR engagement.
The imbalance between Bim and Mcl‐1 expression controls the survival of human myeloma cells
Authors: Gomez‐Bougie Patricia , Bataille Régis , Amiot Martine
Published: October 2004

Multiple myeloma is a fatal B cell malignancy characterized by the accumulation of plasma cells within the bone marrow. IL‐6 is a major survival factor for myeloma cells. Bcl‐2 protein family regulates pathways to apoptosis that are activated upon growth factor deprivation. Pro‐apoptotic proteins that have only a single Bcl‐2 homology domain, BH3‐only, are potent inducers of apoptosis. In myeloma cells, Mcl‐1 has been shown to be a major anti‐apoptotic protein that appears to regulate cell survival through the JAK/STAT pathway. In this study, we examined the regulation of the BH3‐only protein Bim and its interaction with Mcl‐1. The three major Bim isoforms are expressed in myeloma cells and are negatively regulated by IL‐6. Blockade of IL‐6 signaling induces an up‐regulation of Bim concomitant to Mcl‐1 down‐regulation. Of major interest, Bim is found strongly associated with Mcl‐1 in viable myeloma cells while this interaction is disrupted under apoptosis induction. Of note, while Bim is also found strongly associated to Bcl‐2, this interaction is not changed under apoptosis induction. Thus, in myeloma cells, Mcl‐1 neutralizes Bim through complex formation and therefore prevents apoptosis. Under apoptosis induction, the disappearance of Mcl‐1 allows Bim to exercise its pro‐apoptotic function and to activate Bax.