bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of ovarian angiogenesis and apoptosis by GnRH‐I analogs
Authors: Parborell Fernanda , Irusta Griselda , Rodríguez Celín Alejandra , Tesone Marta
Published: September 2007

An adequate vascular supply is important to provide endocrine and paracrine signals during follicular development. We evaluated the direct in vivo effects of both the GnRH‐agonist Leuprolide acetate (LA) and the GnRH‐antagonist Antide (Ant) on the expression of VEGF‐A and ANPT‐1 and their receptors in ovarian follicles from prepubertal eCG‐treated rats. We also examined whether the changes observed in apoptosis by GnRH‐I analogs have an effect on the caspase cascade. LA significantly decreased the levels of VEGF‐A, its receptor Flk‐1, and ANPT‐1 when compared to controls, while the co‐injection of Ant interfered with this effect. No changes were observed in the levels of Tie‐2 after treatment with these analogs. When we measured the follicular content of caspase‐3 protein, we observed that LA significantly increased the level of the active form. The co‐injection of Ant interfered with this effect and Ant alone significantly decreased caspase‐3 cleavage. IHC analyses corroborated these data. Notably, while LA increased caspase‐3 activity levels, Ant decreased them when compared to controls. In follicles obtained from LA‐treated rats, cleavage of PARP (a substrate of caspase‐3) from the intact 113‐kDa protein showed a significant enhancement in an 85‐kDa fragment. The co‐injection of Ant interfered with this effect. Ant alone significantly decreased PARP cleavage as compared to controls. We conclude that the decrease in VEGF‐A, its receptor Flk‐1/KDR, and ANPT‐1 produced by the administration of GnRH‐I agonist is one of the mechanisms involved in ovarian cell apoptosis. This suggests an intraovarian role of an endogenous GnRH‐like peptide in gonadotropin‐induced follicular development. Mol. Reprod. Dev. 75: 623–631, 2008. © 2007 Wiley‐Liss, Inc.
Mapping of the cerebral vascular response to hypoxia and hypercapnia using quantitative perfusion MRI at 3 T
Authors: Nöth Ulrike , Kotajima Futoshi , Deichmann Ralf , Turner Robert , Corfield Douglas R.
Published: September 2007

Changes in breathing change the concentration of oxygen and carbon dioxide in arterial blood resulting in changes in cerebral blood flow (CBF). This mechanism can be described by the cerebral vascular response (CVR), which has been shown to be altered in different physiological and pathophysiological states. CBF maps of grey matter (GM) were determined with a pulsed arterial spin labelling technique at 3 T in a group of 19 subjects under baseline conditions, hypoxia, and hypercapnia. Experimental conditions allowed a change in either arterial oxygen (hypoxia) or carbon dioxide (hypercapnia) concentration compared with the baseline, leaving the other variable constant, in order to separate the effects of these two variables. From these results, maps were calculated showing the regional distribution of the CVR to hypoxia and hypercapnia in GM. Maps of CVR to hypoxia showed very high intra‐subject variations, with some GM regions exhibiting a positive response and others a negative response. Per 10% decrease in arterial oxygen saturation, there was a statistically significant 7.0 ± 2.9% (mean ± SEM) increase in GM‐CBF for the group. However, 70% of subjects showed an overall positive CVR (positive responders), and the remaining 30% an overall negative CVR (negative responders). Maps of CVR to hypercapnia showed less intra‐subject variation. Per 1 mm Hg increase in partial pressure of end‐tidal carbon dioxide, there was a statistically significant 5.8 ± 0.9% increase in GM‐CBF, all subjects showing an overall positive CVR. As the brain is particularly vulnerable to hypoxia, a condition associated with cardiorespiratory diseases, CVR maps may help in the clinic to identify the areas most prone to damage because of a reduced CVR. Copyright © 2007 John Wiley & Sons, Ltd.
Two‐sided bounds on the convergence rate of two‐level methods
Authors: Zikatanov Ludmil T.
Published: September 2007

In this paper, we prove two‐sided bounds on the convergence rate of a standard two‐level subspace correction method. We then apply these estimates to show that a two‐level method with point‐wise smoother for variational problem in H0(curl) does not have optimal convergence rate. This result justifies the conclusion, observed numerically and reported in the literature, that a point relaxation as a smoother does not lead to an optimal multigrid method. In fact, we show that for such problems using a well‐conditioned smoother will always lead to a method that is not optimal. Copyright © 2007 John Wiley & Sons, Ltd.
Reduced‐order suboptimal control design for a class of nonlinear distributed parameter systems using POD and θ–Dtechniques
Authors: Padhi Radhakant , Xin Ming , Balakrishnan S. N.
Published: September 2007

A new computational tool is presented in this paper for suboptimal control design of a class of nonlinear distributed parameter systems (DPSs). In this systematic methodology, first proper orthogonal decomposition‐based problem‐oriented basis functions are designed, which are then used in a Galerkin projection to come up with a low‐order lumped parameter approximation. This technique has evolved as a powerful model reduction technique for DPSs. Next, a suboptimal controller is designed using the emerging θ–Dtechnique for lumped parameter systems. This time domain control solution is then mapped back to the distributed domain using the same basis functions, which essentially leads to a closed form solution for the controller in a state‐feedback form. We present this technique for the class of nonlinear DPSs that are affine in control. Numerical results for a benchmark problem as well as for a more challenging representative real‐life nonlinear temperature control problem indicate that the proposed method holds promise as a good optimal control design technique for the class of DPSs under consideration. Copyright © 2007 John Wiley & Sons, Ltd.
Privatisation and regulation in an Asian transitional economy: the case of Mongolia
Authors: Marshall Richard , Nixson Frederick , Walters Bernard
Published: September 2007

Mongolia's transition to a market economy has entailed rapid and extensive privatisation accompanied by,inter alia, stabilisation, liberalisation and de‐regulation. The primary objective of this strategy was to cement the new political and economic order. Little weight was given to the problems created by the privatisation programme and only limited consideration given to questions of regulation in the economic, social and environmental spheres. However, the failure of the economy to translate economic growth into poverty reduction and the acceleration of the privatisation programme, which includes the progressive transfer of land, and proposals to privatise health, educational and cultural assets, have made regulation a more pressing issue. New, powerful social classes and interest groups have emerged, which have contributed to regulatory failure and capture and have undermined public policy. We identify a range of issues relating to privatisation and regulation and discuss the degree to which they are being addressed by the post‐1990 political class. Although there exist a number of regulatory agencies, there is a lack of political commitment, and only piecemeal implementation and enforcement. The scarcity of experienced and technically competent staff capable of establishing and operating effective regulatory agencies and ensuring compliance is also a major problem. Copyright © 2007 John Wiley & Sons, Ltd.
Laboratory markers of thrombosis risk in children with hereditary spherocytosis
Authors: Troendle Sarah B. , Adix Leah , Crary Shelley E. , Buchanan George R.
Published: September 2007

Background

Recent data suggest that adults with hereditary spherocytosis (HS) may be protected from atherothrombosis before splenectomy but have increased risk of thrombosis following splenectomy. In order to aid in making informed decisions regarding splenectomy in children with HS, we conducted a retrospective study of several surrogate laboratory markers of thrombosis risk in children with HS.

Methods

A retrospective record review was performed on 246 children with HS. Platelet count and hemoglobin concentration were recorded prior to and following splenectomy in each patient. Serum cholesterol levels were collected from the record when available.

Results

Prior to splenectomy, hypocholesterolemia was common. Mean platelet counts in 31 evaluable patients pre‐ and post‐splenectomy were 334 and 608 × 109/L, respectively (P < 0.001). Twenty‐nine patients (94%) exhibited persistent thrombocytosis following splenectomy. Hemoglobin values following splenectomy often rose to higher than age and gender‐matched norms, with 30% of measurements greater than the 90th percentile and 17% greater than the 97th percentile.

Conclusions

The findings of hypocholesterolemia before splenectomy and thrombocytosis and mild polycythemia afterwards support the hypothesis that patients with HS might be protected from thrombosis before splenectomy and/or more susceptible afterwards. Prospective studies of additional prothrombotic biomarkers and thrombotic events in HS patients are warranted. Pediatr Blood Cancer 2007;49:781–785. © 2007 Wiley‐Liss, Inc.
An instructive example of a long‐latency adverse drug reaction—sclerosing peritonitis due to practolol
Authors: Mann Ronald D.
Published: September 2007

Objective

By examination of the original Yellow Card data to determine the duration of the latent period of the sclerosing peritonitis which formed part of the oculomucocutaneous syndrome that was associated with practolol, the beta‐adrenergic receptor blocking agent that was withdrawn from clinical usage in the UK in December 1975 in response to reports of the syndrome.

Method

Relevant drug analysis prints (DAPs) for practolol were obtained from the Medicines and Healthcare Products Regulatory Agency (MHRA) and, by application to the Interim Committee on Yellow Card data, copies were obtained of the anonymised Yellow Card reports for all the 201 cases of sclerosing peritonitis that were reported in patients treated with practolol. These data were used to determine the latent period of this iatrogenic adverse drug reaction.

Results

It was shown that no other cause than practolol operated in all or a majority of the cases of sclerosing peritonitis and the suspected adverse reaction could properly be attributed to the drug. The latent period (the time period between the drug start date and the reaction start date) of the sclerosing peritonitis associated with practolol averaged 201 weeks (range 26–606 weeks; standard deviation 130 weeks).

Conclusion

The latent period of the sclerosing peritonitis that formed part of the practolol oculomucocutaneous syndrome averaged about 4 years and had a range of from 0.5 to over 11.5 years. The Yellow Card Scheme could detect this ultra long‐latency adverse reaction. Copyright © 2007 John Wiley & Sons, Ltd.
Carbon nanotube‐reinforced polyacrylonitrile nanofibers by vibration‐electrospinning
Authors: Wan Yu‐Qin , He Ji‐Huan , Yu Jian‐Yong
Published: September 2007

Carbon nanotubes (CNTs) are thought to be perfect enhancive materials for composites. Multi‐wall carbon nanotubes were directly electrospun into polyacrylonitrile (PAN) nanofibers via both traditional electrospinning and vibration‐electrospinning. The fibers obtained were examined by scanning electron microscopy and X‐ray diffraction. CNTs were aggregated heavily in the fibers obtained by traditional electrospinning while CNTs were well distributed and aligned in PAN fibers obtained by vibration‐electrospinning. Copyright © 2007 Society of Chemical Industry
Mathematical models for continuous electrospun nanofibers and electrospun nanoporous microspheres
Authors: He Ji‐Huan , Xu Lan , Wu Yue , Liu Yong
Published: September 2007

A brief review of mathematical models of electrospinning is given. The nano‐effect and electrospinning dilation are presented to explain how to prepare extremely high strength continuous nanofibers and nanoporous microspheres, respectively. According to the established models, vibration‐electrospinning is introduced to improve electrospinability, Siro‐electrospinning is suggested to mimic the spinning procedure of a spider and magneto‐electrospinning is used to control the instability arising in the electrospinning process. A new theory linked to both classical mechanics and quantum mechanics should be developed to explain certain special phenomena in electrospinning. E‐infinity theory is considered to be a potential theory to deal with quantum‐like properties and nano‐effect on the nanoscale. The emphasis of this brief review is upon the authors' recent work, and the references are not exhaustive. Copyright © 2007 Society of Chemical Industry
Engineering electrospun nanofibrillar surfaces for spinal cord repair: a discussion
Authors: Meiners Sally , Ahmed Ijaz , Ponery Abdul S , Amor Nathan , Harris Suzan L , Ayres Virginia , Fan Yuan , Chen Qian , Delgado‐Rivera Roberto , Babu Ashwin N
Published: September 2007

BACKGROUND: The design of implants comprised of biodegradable electrospun nanofibers for the purpose of bridging injuries in damaged spinal cord is discussed. Electrospun nanofibers structurally mimic the extracellular matrix on which neurons and other cell types grow in vivo. This property has created great interest for their use in tissue engineering applications. However, their employment as biomimetic surfaces for such in vivo applications is still in its infancy.

RESULTS: A nonwoven fabric comprised of electrospun polyamide nanofibers supported modest axonal regeneration in injured adult rat spinal cord. Covalent modification of the nanofibers with a bioactive peptide derived from the neuroregulatory extracellular matrix molecule tenascin‐C enhanced the ability of the nanofibers to facilitate axonal regrowth. However, the random orientation of the nanofibrillar fabric folds was an impediment to the forward movement of axons.

CONCLUSIONS: Polyamide nanofibers covalently modified with neuroactive molecules provide a promising material for grafts to promote spinal cord regeneration. However, for the proper guidance of regrowing axons, attention must be paid to the engineering of ordered nanofibrillar structures. Copyright © 2007 Society of Chemical Industry
Lead‐free on‐laminate laser soldering: a new module assembling concept
Authors: Gast Maren , Köntges Marc , Brendel Rolf
Published: September 2007

We demonstrate lead‐free laser soldering of standard industrial solar cells. The laser‐soldered contacts stay stable for more than 240 accelerated ageing cycles by humidity–freeze test and withstand peel forces in excess of 10 N/cm. Laser soldering is demonstrated while the cells are lying on the ethylene vinyl acetate (EVA) foil. This permits to connect the solar cells to the lead‐free tinned copper ribbons directly on the lamination materials. We also demonstrate soldering on the bottom side by lasering through the glass and the non‐polymerized EVA. With the aid of a pick and place robot it thus becomes possible to avoid all string handling. On‐laminate laser soldering (OLLS) technique, which permits a high level of automation and process control, induces little thermal and mechanical stress, reduces the handling and should thus be of particular advantage for assembling modules with very thin cells at a high yield. Copyright © 2007 John Wiley & Sons, Ltd.
A two‐dimensional proteome reference map of Herbaspirillum seropedicae proteins
Authors: Chaves Daniela Fojo Seixas , Ferrer Pércio Pereira , de Souza Emanuel Maltempi , Gruz Leonardo Magalhães , Monteiro Rose Adele , de Oliveira Pedrosa Fábio
Published: September 2007

Herbaspirillum seropedicae is an endophytic diazotroph associated with economically important crops such as rice, sugarcane, and wheat. Here, we present a 2‐D reference map for H. seropedicae. Using MALDI‐TOF‐MS we identified 205 spots representing 173 different proteins with a calculated average of 1.18 proteins/gene. Seventeen hypothetical or conserved hypothetical ORFs were shown to code for true gene products. These data will support the genome annotation process and provide a basis on which to undertake comparative proteomic studies.
A novel late embryogenesis abundant protein and peroxidase associated with black point in barley grains
Authors: March Timothy J. , Able Jason A. , Schultz Carolyn J. , Able Amanda J.
Published: September 2007

Black point of barley grain is a disorder characterised by a brown‐black discolouration at the embryo end of the grain. Black point is undesirable to the malting industry and results in significant economic loss annually. To identify proteins associated with barley black point we utilised a proteomic approach with 2‐DE to compare proteins from whole grain samples of black pointed and healthy grain. From this comparison two condition‐specific proteins were identified: a novel 75 kDa late embryogenesis abundant (LEA) protein and a barley grain peroxidase 1 (BP1) that were specifically more abundant in healthy grain and black pointed grain, respectively. Although LEA protein was less abundant in black pointed grain, LEA gene expression was greater suggesting protein degradation had possibly occurred in black pointed grain. Similarly, the increase in BP1 in black pointed grain could not be explained by gene expression. Western blot analysis also revealed that the identified LEA protein is biotinylated in vivo. The role that each of these proteins might have in black point development is discussed.
Photo‐ and thermochromic cation sensitive spiro[indoline‐pyridobenzopyrans]
Authors: Chernyshev Anatoly V. , Metelitsa Anatoly V. , Gaeva Elena B. , Voloshin Nikolai A. , Borodkin Gennady S. , Minkin Vladimir I.
Published: September 2007

The photo‐ and thermochromic behaviour of a series of spiro[indolinepyridobenzopyrans] 1–5 has been studied. The thermodynamic and kinetic parameters of the thermal equilibria between the ring‐closed and ring‐opened (merocyanine) isomeric forms of spiropyrans have been determined using UV–Vis absorption and 1H NMR spectroscopies techniques. The most stable form of 1‐(2‐hydroxyethyl)‐spiro[indoline‐pyridobenzopyran] 4 is represented by its trans‐(hydroxystyryl)oxazolidineindoline isomer coexisting in acetone solution with the ring‐closed spiroform. In the presence in solution of metal salts, spiro[indoline‐pyridobenzopyrans] exhibit strong ionochromic effect due to the formation of complexes with the merocyanine ligand. The composition of the complexes formed by Zn2+ and Ni2+ ions has been determined with the use of spectrophotometric and electrospray ionisation mass spectroscopy techniques. The stepwise stability constants and spectral properties of the most stable 1:1 and 1:2 metal/merocyanine complexes have been determined. Selectivity of the complexation reaction depends on the position of the thermochromic equilibrium. Copyright © 2007 John Wiley & Sons, Ltd.
Substituent effect of diarylethenes on IR spectra for application of non‐destructive readout of photochromic recording
Authors: Takata Atsushi , Yokojima Satoshi , Nakagawa Hirotomo , Matsuzawa Yuji , Murakami Akinori , Nakamura Shinichiro , Irie Masahiro , Uchida Kingo
Published: September 2007

Photochromic diarylethene derivatives, 1,2‐bis(2‐methyl‐5‐phenyl‐3‐thienyl)perfluorocyclopentene (1), 1,2‐bis(2,4‐dimethyl‐5‐phenyl‐3‐thienyl)perfluorocyclopentene (2), and 1,2‐bis(2‐methoxy‐5‐phenyl‐3‐thienyl) perfluorocyclopentene (3) were prepared to study substituent effects on IR spectra. The origin of the change of IR spectra due to the substituents may be categorized into (1) change in structure, (2) change in charge distribution, and (3) new normal modes due to the newly introduced substituent, which was examined by ab initio quantum chemical calculations. Comparisons between the experimental and computational IR spectra clarified the difference of the substituent effects between open‐ and closed‐ring isomers. Such understanding should be useful for designing diarylethene derivatives in use for non‐destructive readout by IR light. Copyright © 2007 John Wiley & Sons, Ltd.
Fluorene‐based liquid crystalline networks with linearly polarized blue emission
Authors: Millaruelo Marta , Chinellato Luiz S. , Serrano José Luis , Oriol Luis , Piñol Milagros
Published: September 2007

A series of fluorene‐based luminophores containing methacrylic end groups have been prepared and incorporated into uniaxially oriented liquid crystalline films by in situ photopolymerization. Various structural modifications on the 2‐(4‐cyanophenyl)fluorene core, which include alkyl chains at the 9‐position and elongation of the rigid core with one additional phenyl ring, have been investigated to generate emitters with adjusted liquid crystal compatibility, improved luminescence and dichroic properties. Polarized blue‐emitting films were produced that had an acceptable photostability, and it was found that the polarization emission was better for samples with low (5%) cross‐linker contents. Polarization of the luminescence was favored by the liquid crystalline properties of the luminophore. In addition, the detrimental effect of the alkyl substituent at the fluorene core on the mesomorphism and on the emission polarization can be overcome by lengthening the π‐system. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4804–4817, 2007
Living cationic polymerization of vinyl ether with a cyclic acetal group
Authors: Namikoshi Takeshi , Hashimoto Tamotsu , Urushisaki Michio
Published: September 2007

The living cationic polymerization of 5‐ethyl‐2‐methyl‐5‐(vinyloxymethyl)‐1,3‐dioxane (1), a vinyl ether with a cyclic acetal unit, was investigated with various initiating systems in toluene or methylene chloride at 0 to −30 °C. With initiating systems such as hydrogen chloride (HCl)/zinc chloride (ZnCl2), isobutyl vinyl ether–acetic acid adduct [CH3CH(OiBu)OCOCH3]/tin tetrabromide (SnBr4)/di‐tert‐butylpyridine (DTBP), and CH3CH(OiBu)OCOCH3/ethylaluminum sesquichloride (Et1.5AlCl1.5)/ethyl acetate (CH3COOEt), the number‐average molecular weights (Mn's) of the obtained poly(1)s increased in direct proportion to the monomer conversion and produced polymers with relatively narrow molecular weight distributions [MWDs; weight‐average molecular weight/number‐average molecular weight (Mw/Mn) = 1.2–1.3]. To investigate the living nature of the polymerization with CH3CH(OiBu)OCOCH3/SnBr4/DTBP, a second monomer feed was added to the almost polymerized reaction mixture. The added monomer was completely consumed, and the Mn values of the polymers showed a direct increase against the conversion of the added monomer, indicating the formation of a long‐lived propagating species. The glass transition temperature and thermal decomposition temperature of poly(1) (e.g., Mn = 13,600, Mw/Mn = 1.30) were 29 and 308 °C, respectively. The cyclic acetal group in the pendants of the polymer of 1 could be converted to the corresponding two hydroxy groups in a 65% yield by an acid‐catalyzed hydrolysis reaction. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4855–4866, 2007
Synthesis and electroluminescent properties of a phenothiazine‐based polymer for nondoped polymer light‐emitting diodes with a stable orange‐red emission
Authors: Liu Yingliang , Cao Huayu , Li Jianghui , Chen Zhijian , Cao Shaokui , Xiao Lixin , Xu Shengang , Gong Qihuang
Published: September 2007

A novel phenothiazine‐based polymer was synthesized through the Heck reaction of 3,7‐divinyl‐N‐octyl‐phenothiazine with 4,7‐dibromo‐2‐octylbenzotriazole according to the alternating donor–acceptor strategy. The polymer was characterized with 1H NMR, infrared spectroscopy, gel permeation chromatography, cyclic voltammetry, ultraviolet–visible spectroscopy, and fluorescence spectroscopy. With the polymer used as an active layer, three nondoped polymer light‐emitting diodes (PLEDs) with a double‐layer configuration were fabricated by the spin‐coating approach with different thermal annealing processes. The emission maximum in electroluminescent spectra was stabilized at 616 nm. The maximum luminance reached 2432 cd/m2. The coordinate value of Commission International de l'Eclairage 1931 in the double‐layer PLEDs after the thermal treatment was nearly stabilized at (x, y) =(0.62, 0.38). Additionally, the luminous efficiency of device II reached a balanceable state with an increase in the current. Therefore, the polymer had an orange‐red emission with stable chromaticity coordinates under different driving voltages. Finally, a nondoped device with a stable luminous efficiency and chromaticity was obtained. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4867–4878, 2007
Influence of specific muscle training on pain, activity limitation and kinesiophobia in women with back pain post‐partum — A ‘Single‐subject research design’
Authors: Gustafsson Johanna , Nilsson‐Wikmar Lena
Published: September 2007

Background and Purpose. Many women suffer from back pain and experience activity limitation post‐partum. To our knowledge the physiological factors and physiotherapy related to back pain post‐partum have received limited evaluation and the effectiveness of specific physiotherapeutic approaches to exercise should be tested. In addition, there has been limited research on kinesiophobia in women with back pain post‐partum. The purpose of the current study was to test the influence of specific trunk muscle training on pain, activity limitation and kinesiophobia in 10 subjects with back pain post‐partum. Method. The treatment consisted of specific deep muscle training of the transversus abdominus and multifidus muscles. Pain was rated based on the visual analogue scale (VAS) and pain drawings. Activity limitation was recorded using the Disability Rating Index. Kinesiophobia was evaluated using the Swedish version of the Tampa Scale for Kinesiophobia. An A–B–A single‐subject research design was used and a number of measurements were obtained during each phase. The analysis consisted of a visual inspection and a two standard deviation band test (2‐SD). Results. The visual analysis showed a trend towards reduced pain and activity limitation for all 10 subjects. The 2‐SD test showed mixed results among all subjects. In addition, all subjects reported kinesiophobia before and after treatment. Conclusions. Individual specific deep muscle training of the transversus abdominus and multifidus muscles reduced pain and activity limitation in women with back pain post‐partum. Further research is needed to determine more precisely how kinesiophobia affects women with back pain post‐partum. Copyright © 2007 John Wiley & Sons, Ltd.
Recommended management of mental health disorders
Authors: Hindley Peter
Published: September 2007

Our series Prescribing in children gives practical advice for successful management of childhood problems in general practice. Here, Dr Hindley describes the management of mental health disorders encompassing drug treatments and social/psychological interventions. Copyright © 2007 Wiley Interface Ltd
1,4‐Diazepine‐2,5‐dione ring formation during solid phase synthesis of peptides containing aspartic acid β‐benzyl ester
Authors: Süli‐Vargha Helga , Schlosser Gitta , Ilaš Janez
Published: September 2007

The Fmoc‐based SPPS of H‐Xaa‐Asp(OBzl)‐Yaa‐Gly‐NH2 sequences results in side reactions yielding not only aspartimide peptides and piperidide derivatives, but also 1,4‐diazepine‐2,5‐dione‐peptides. Evidence is presented to show that the 1,4‐diazepine‐2,5‐dione derivative is formed from the aspartimide peptide. The rate of this ring transformation depends primarily on the tendency to aspartimide and piperidide formation, which is influenced by the nature of the amino acid following the aspartic acid β‐benzyl ester (Xaa). However the bulkiness of the amino acid side chain preceeding the aspartic acid β‐benzyl ester (Yaa) is also important. Under certain conditions the 1,4‐diazepine‐2,5‐dione peptide derivative may even be formed dominantly, which is a highly undesirable side reaction in peptide synthesis, but which provides a new way for the synthesis of diazepine peptide derivatives with targeted biological or pharmacological activity. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Viral peptide immunogens: current challenges and opportunities
Authors: Azizi Ali , Diaz‐Mitoma Francisco
Published: September 2007

Synthetic peptide vaccines have potential to control viral infections. Successful experimental models using this approach include the protection of mice against the lethal Sendai virus infection by MHC class I binding CTL peptide epitope. The main benefit of vaccination with peptide epitopes is the ability to minimize the amount and complexity of a well‐defined antigen. An appropriate peptide immunogen would also decrease the chance of stimulating a response against self‐antigens, thereby providing a safer vaccine by avoiding autoimmunity. In general, the peptide vaccine strategy needs to dissect the specificity of antigen processing, the presence of B‐and T‐cell epitopes and the MHC restriction of the T‐cell responses. This article briefly reviews the implications in the design of peptide vaccines and discusses the various approaches that are applied to improve their immunogenicity. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Synthesis of cyclooctapeptides: constraints analogues of the peptidic neurotoxin, ω‐agatoxine IVB—an experimental point of view
Authors: Minta Ewelina , Kafarski Pawel , Martinez Jean , Rolland Valérie
Published: September 2007

ω‐AGA IVB is an important lead structure when considering the design of effectors of glutamate release inducting P/Q‐type calcium channels. The best route to achieve the analogues possessing the three‐dimensional arrangement corresponding to the native binding loop was the introduction of constraint by ring formation via side chain to side chain lactamization for suitably protected Lys and Glu residues. Since tryptophane residue located at position 14 of this neuropeptide has been suggested as essential for binding, analogues in which this amino acid was replaced by aza‐tryptophane and alanine were synthesized. The synthesis was carried out on various acid‐labile resins (BARLOS chlorotrityl, Rink amide, PEG‐based or Wang resins), by Fmoc strategy. In this paper, we describe optimization of the peptide cyclization with various protecting groups, and on resin or in solution cyclization experimental parameters. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
GISAXS study of the alignment of oriented carbon nanotubes grown on plain SiO2/Si(100) substrates by a catalytically enhanced CVD process
Authors: Mane Mane J. , Cojocaru C. S. , Barbier A. , Deville J. P. , Thiodjio Sendja B. , Le Normand F.
Published: September 2007

We report a quantitative Grazing Incidence Small Angle X‐Ray Scattering (GISAXS) study of the alignment of mutually oriented carbon nanotubes (CNTs) grown by a catalytically‐activated, a plasma direct current and hot filaments‐assisted (DC HF CCVD) process. Metallic catalytic (Co) islands were dispersed on plain SiO2 (5 nm thickness)/Si(100) substrates prior the growth of CNTs which can be considered as highly anisotropic 1D nanostructures. The GISAXS pattern analysis in the framework of the Distorted‐Wave Born Approximation (DWBA) has been expanded to multilayered non‐correlated surface science systems (non‐correlated carbon nanotubes) and is based on the determination of carbon nanotubes density, characteristic lengths, atomic Co dispersion throughout the CNTs and roughnesses of the uncorrelated particles. Even dominated by envelope features of disordered objects, they provide noticeable information about CNTs films: both structural (orientation, size and length distribution) and correlation (density, mutual alignment) information. The results stand in rather good agreement with the Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) observations. Moreover, the GISAXS patterns could only be satisfactorily reproduced by adding a mixed C–Co contribution between the pure carbon and the metallic cobalt let on top of the CNT, inferring that cobalt continuously fills the nanotube in the course of the growth and that the CNTs experience a large tendency toward mutual alignment. The effect of variable X‐ray incidence angles has been investigated. With a weak addition of ammonia (from 1% to 3% of the gas mixture) the density has been found to decrease by more than one order of magnitude. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Three‐Dimensional Holographic Vector of Atomic Interaction Field Applied in QSAR of Anti‐HIV HEPT Analogues
Authors: Tong Jianbo , Liu Shuling
Published: September 2007

A newly developed Three‐Dimensional Holographic Vector of Atomic Interaction Field (3D‐HoVAIF) was used to describe the chemical structures of 35 anti‐human immunodeficiency virus drugs as 1‐[(2‐Hydroxyethoxy)‐Methyl]‐6‐(Phenylthio)Thymine (HEPT). Here two Quantitative Structure–Activity Relationship (QSAR) models were built by both Partial Least Square (PLS) regression and Support Vector Machine (SVM) regression. Both estimation stability and prediction ability of these models were strictly analyzed by both internal and external validations. The correlation coefficient (R2) of established PLS and SVM models, Leave‐One‐Out (LOO) Cross‐Validation (CV), prediction values versus experimental ones of external samples were Rcum2=0.922, QCV2=0.656, Qext2=0.624 (PLS) and Rcum2=0.821, QCV2=0.797, Qext2=0.771 (SVM), respectively. The results of SVM were found to be better than those of PLS and Multiple Linear Regression (MLR) as previously reported by Garg et al. (Chem. Rev. 1999, 99, 3525–3601), which had both favorable estimation stability and good prediction capabilities. Satisfactory results showed that 3D‐HoVAIF could preferably express information related to biological activity of HEPT.
Robust discontinuous exponential regulation of dynamic nonholonomic wheeled mobile robots with parameter uncertainties
Authors: Ma B. L. , Tso S. K.
Published: September 2007

For regulating a dynamic nonholonomic WMR (wheeled mobile robot) with parameter uncertainties, we derive a simple robust discontinuous control law, yielding a global exponential convergence of position and orientation to the desired set point despite parameter uncertainties. The controller design relies on separating the error dynamics into two subsystems, followed by robust feedback control laws to stabilize the subsystems. The effectiveness of the proposed control laws is verified by simulation. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis of Magnetic Microspheres with Controllable Structure via Polymerization‐Triggered Self‐Positioning of Nanocrystals
Authors: Xia Ao , Hu Jianhua , Wang Changchun , Jiang Donglin
Published: September 2007

A facile and novel method for the synthesis of magnetite–polymer hybrid microspheres with controllable structure is reported. On the basis of the interactions between polymers and magnetic nanocrytals, which are coated with a primary oleic acid layer, a variety of magnetic microspheres with well‐tailored structure are fabricated by carefully modulating polymerization and selecting components of composite microspheres; the evolvement of hierarchical structure, and the magnetic properties of microspheres were systematically studied. Importantly, the mechanism of polymerization‐triggered self‐positioningof magnetic nanocrystals is investigated.
Adaptation of a career portfolio at Georgia Tech: A case study
Authors: Mobley Ralph
Published: September 2007

This chapter describes the planning, development, testing, and implementation of Georgia Tech's online career portfolio, as well as the challenges associated with adaptation of the program.
Program evaluation of e‐portfolios
Authors: Reardon Robert C. , Hartley Sarah Lucas
Published: September 2007

This chapter provides a description of the various types of e‐portfolios, a discussion of program development considerations, and an overview of e‐portfolio evaluation models.
Neurophysiological actions of methylphenidate in the primary somatosensory cortex
Authors: Drouin Candice , Wang Dorothy , Waterhouse Barry D.
Published: September 2007

As a catecholamine reuptake blocker, methylphenidate (MPH) enhances noradrenergic transmission and is likely to influence norepinephrine actions in sensory systems. To characterize neurophysiological actions of MPH in the primary somatosensory (SI) cortex, we recorded basal and whisker deflection‐evoked discharge of infragranular sensory cortical neurons, before and after intraperitoneal administrations of saline and MPH (5 mg/kg) in halothane‐anesthetized rats. MPH had two types of actions on sensory‐evoked neuronal responses in the SI cortex, depending on the initial amplitude of the sensory response. When the whisker deflection induced a small excitatory response under control conditions, MPH significantly increased the amplitude of the response by ∼40%. When the whisker stimulation induced a large excitatory response under control conditions, MPH did not significantly alter the amplitude of the response, but significantly decreased the duration and the peak latency of the response, so that the response was more focused. These neurophysiological actions of MPH may underlie some of the beneficial effects of the drug on sensory processing and attention.Synapse 61:985–990, 2007. © 2007 Wiley‐Liss, Inc.
Faculty members' social identities and classroom authority
Authors: Chesler Mark , Young Jr Alford A.
Published: September 2007

How do faculty members' social group identities influence their choices about how they present themselves and their course materials? How do these identities affect student responses to them and the material they present?
Acts of diversity: Assessing the impact of service‐learning
Authors: Paoletti Jo B. , Segal Eden , Totino Christina
Published: September 2007

This chapter explores the challenges of assessing multicultural learning in a service‐learning course and offers a variety of strategies for measuring student development.
Diversity combining with up‐link power control
Authors: Nam Sung Sik , Alouini Mohamed‐Slim , Qaraqe Khalid A.
Published: September 2007

We introduce in this paper a new adaptive power‐controlled diversity combining scheme that reduces the average transmitted power of the mobile units (MUs) while meeting a certain minimum required quality of service. The key idea is (i) to collect and combine all the available diversity paths at the base station (BS) and then (ii) to request the MU to increase or decrease its transmitted power just to track the required target signal‐to‐noise ratio (SNR). Four power control variants accounting for practical implementation constraints including discrete power levels and transmitter gain saturation are proposed and studied. Some selected numerical results show that the proposed scheme offers considerable savings in the transmitted power levels over a wide SNR range but amplifier saturation leads to a violation of the target BER requirement in the low average SNR range. Additional numerical examples show that the power control variants that take into account practical implementation constraints conserve the main features of the ideal continuous power algorithm. Copyright © 2007 John Wiley & Sons, Ltd.
QuESt: a QoS‐based energy efficient sensor routing protocol
Authors: Saxena Navrati , Roy Abhishek , Shin Jitae
Published: September 2007

Rapid penetration of smart wireless devices and enormous growth of wireless communication technologies has already set the stage for deployment of wireless sensor networks (WSNs). While these small sensor nodes are often considered as the future of wireless communications, they also suffer from energy constraints. On the other hand, with increasing demand for real‐time services in next generation wireless networks, quality‐of‐service (QoS)‐based routing has emerged as an interesting research topic. Naturally offering some QoS‐guarantee in sensor networks raises significant challenges. The network needs to cope up with battery‐constraints, while providing precise QoS (end‐to‐end delay and bandwidth requirement) guarantee. More precisely, designing such QoS‐protocols, optimizing multiple objectives, is computationally intractable. Based on the multi‐objective genetic algorithm (MOGA), in this paper we propose a QoS‐based energy‐efficient sensor routing (QuESt) protocol that determines application‐specific, near‐optimal sensory‐routes demand, by optimizing multiple QoS parameters, (end‐to‐end delay and bandwidth requirements) and energy consumption. Simulation results demonstrate that the proposed protocol is capable of discovering a set of QoS‐based, near‐optimal routes, even with imprecise network information. Copyright © 2007 John Wiley & Sons, Ltd.
On the performance of BICM with mapping diversity in hybrid ARQ
Authors: Szczecinski Leszek , Diop Fatou‐Kiné , Benjillali Mustapha
Published: September 2007

Hybrid ARQ with packet combining for high‐order modulations (such as 16‐QAM) may be significantly enhanced if the bits‐to‐symbols mappings are appropriately changed throughout the transmissions. In this paper, we analyze the relationship between such mapping diversity and channel coding. We calculate the capacity of the popular bit‐interleaved‐coded modulation (BICM) to draw qualitative and approximate quantitative conclusions that are valid for strong codes approaching the capacity limits. We conclude that the choice/design of the appropriate mapping depends on the targeted spectral efficiency and we demonstrate that certain forms of mapping diversity may be counterproductive. We also show that iterative demapping may be successfully applied to significantly reduce (by more than 1 dB) the gap between the BICM and coded modulations (CM) capacities. The analysis is illustrated with results obtained when the mapping diversity is combined with practical turbo codes. Copyright © 2007 John Wiley & Sons, Ltd.
Application and methodology of in vivo K x‐ray fluorescence of Pb in bone (impact of KXRF data in the epidemiology of lead toxicity, and consistency of the data generated by updated systems)
Authors: Nie Huiling , Hu Howard , Chettle David R.
Published: September 2007

K x‐ray fluorescence (KXRF) technology has been used to make in vivo measurements of lead in bone for more than three decades. The data obtained are beneficial to research on lead toxicity as well as, in certain circumstances, the practice of occupational and environmental medicine. This paper reviews the impact of KXRF data on epidemiologic research involving lead toxicity and demonstrates that bone lead is and will continue to be a valuable biomarker in addressing long‐term health effects related to cumulative exposure. The KXRF system has been improved and upgraded several times ever since it was first used. The consistency of the data obtained from these KXRF systems has been investigated in many studies. This paper provides an overview of the factors that will affect the data generated by the KXRF systems. A calibration problem encountered in one of the major KXRF laboratories is described, and the approach taken to solve the problem is discussed. Despite all the theoretical considerations, there are still some important practical challenges to the intercalibration of KXRF instruments both within the laboratory, and between laboratories. Copyright © 2007 John Wiley & Sons, Ltd.
On the Structure of Entanglement Witnesses and New Class of Positive Indecomposable Maps
Authors: Chruściński Dariusz , Kossakowski Andrzej
Published: September 2007

We construct a new class of positive indecomposable maps in the algebra of d × d complex matrices. Each map is uniquely characterized by a cyclic bistochastic matrix. This class generalizes Choi map for d = 3. It provides a new reach family of indecomposable entanglement witnesses which define important tool for investigating quantum entanglement.
How to Observe Quantum Fields and Recover Them From Observational Data?
Authors: Ojima Izumi , Takeori Mitsuharu
Published: September 2007

On the basis of the mathematical notion of “micro-macro duality” for understanding mutual relations between microsopic quantum systems (micro) and their macroscopic manifestations (macro) in terms of the notion of sectors and order parameters, a general mathematical scheme is proposed for detecting the state-structure inside of a sector through measurement processes of a maximal abelian subalgebra of the algebra of observables. For this purpose, the Kac-Takesaki operators controlling group duality play essential roles, which naturally leads to the composite system of the observed system and the measuring system formulated by a crossed product. This construction of composite systems will be shown to make it possible for the micro to be reconstructed from its observational data as macro in the light of the Takesaki duality for crossed products.
Tensor Product Structures, Entanglement, and Particle Scattering
Authors: Harshman N. L. , Wickramasekara S.
Published: September 2007

Particle systems admit a variety of tensor product structures (TPSs) depending on the complete system of commuting observables chosen for the analysis. Different notions of entanglement are associated with these different TPSs. Global symmetry transformations and dynamical transformations factor into products of local unitary operators with respect to certain TPSs and not with respect to others. Symmetry-invariant and dynamical-invariant TPSs and corresponding measures of entanglement are defined for particle scattering systems.
The Safety of Percutaneous Trigger Finger Release
Authors: Schramm J. Mark , Wongworawat Montri D. , Nguyen Minhthy
Published: September 2007

This study attempted to determine the safety of percutaneous release of trigger fingers, with particular attention given to border digits and the thumb. We performed percutaneous release of the A1 pulley in six fresh frozen cadaveric hands utilizing established surface landmarks. After freezing all specimens, we performed cross-sections at the A1 pulley, avoiding dissection of soft tissues, which could alter the natural position of the digital nerves. There was no difference in the distance from the needle tract to the neurovascular bundle when comparing between digits, and the closest distance was 2.7 mm. There was no significant difference between the needle tract and the radial and ulnar digital nerves. Based on our findings, percutaneous trigger finger release can safely be performed on all digits, including the thumb, small fingers, and index fingers.
Hydrolysis of Epoxidized Soybean Oil in the Presence of Phosphoric Acid
Authors: Guo Yinzhong , Hardesty Jon H. , Mannari Vijay M. , Massingill John L.
Published: September 2007

Ring‐opening hydrolysis of epoxidized soybean oil in the presence of phosphoric acid was studied under varying experimental conditions. The influence of type and amount of solvents, phosphoric acid content and water content on the rate of ring‐opening reactions and the characteristics of the derived products were studied. The soy‐polyols prepared were characterized by determination of hydroxyl content, viscosity measurements, determination of average molecular weight and polydispersity index (GPC). The structural confirmation was done by FT‐IR and 1H‐NMR spectroscopy. The study shows that under the reaction conditions employed, a substantial degree of oligomerization due to oxirane‐oxirane, and/or oxirane‐hydroxyl reaction takes place. It is possible to synthesize soy‐polyols having varying hydroxyl content and phosphate‐ester functionality by controlling the type and amount of polar solvent and phosphoric acid content.