bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction between the ADAM12 and SH3MD1 genes may confer susceptibility to late‐onset Alzheimer's disease
Authors: Harold D. , Jehu L. , Turic D. , Hollingworth P. , Moore P. , Summerhayes P. , Moskvina V. , Foy C. , Archer N. , Hamilton B.A. , Lovestone S. , Powell J. , Brayne C. , Rubinsztein D.C. , Jones L. , O'Donovan M.C. , Owen M.J. , Williams J.
Published: April 2007

The neuropathology of Alzheimer's disease (AD) is characterized by intracellular neurofibrillary tangles and the extracellular deposition of β‐amyloid (Aβ) in senile plaques. Aβ has been shown to mediate neurodegenerative and inflammatory changes associated with amyloid plaques, although the pathological mechanism of Aβ remains largely unknown. Recent evidence suggests that the FISH adapter protein binds to, and potentially regulates, ADAM12 (a disintegrin and metalloprotease 12) to mediate a neurotoxic effect of Aβ. The ADAM12 gene lies on chromosome 10q26.3, and the gene encoding FISH, SH3MD1, lies within a region of linkage to late‐onset AD (LOAD) on 10q25.1. This study investigates whether there is a relationship between variation in ADAM12 and SH3MD1 and susceptibility to LOAD in a sample of 1,051 AD cases and 1,269 matched controls. We observe significant interactions between variants in the two genes that may influence susceptibility to LOAD. The most significant statistical interaction is between rs3740473, a synonymous single nucleotide polymorphism (SNP) in SH3MD1 and rs11244787, an intronic SNP in ADAM12 (effect size = 2.1 for interaction term, P = 0.006). © 2007 Wiley‐Liss, Inc.
Candidate gene association study of insulin signaling genes and Alzheimer's disease: Evidence for SOS2, PCK1, and PPARγ as susceptibility loci
Authors: Hamilton Gillian , Proitsi Petra , Jehu Luke , Morgan Angharad , Williams Julie , O'Donovan Michael C. , Owen Michael J. , Powell John F. , Lovestone Simon
Published: April 2007

Epidemiological evidence supports the existence of a possible link between type II diabetes mellitus (T2DM) and late‐onset Alzheimer's disease (LOAD). Polymorphisms from candidate genes for T2DM were genotyped in a two‐stage approach to identify novel risk factors for LOAD. One hundred fifty‐two polymorphisms were initially genotyped in a case:control cohort: nine SNPs showed individual association with disease status under at least one genetic model, while an additional two SNPs showed a haplotype association. In a replication study, we confirmed significant association of SNPs within three genes—PPARγ, SOS2, and PCK1—with Alzheimer's disease. In particular, our data suggest that the effect of variants within these genes might be influenced by gender. © 2007 Wiley‐Liss, Inc.
Anorexia nervosa, perfectionism, and dopamine D4 receptor (DRD4)
Authors: Bachner‐Melman Rachel , Lerer Elad , Zohar Ada H. , Kremer Ilana , Elizur Yoel , Nemanov Lubov , Golan Moria , Blank Shulamit , Gritsenko Inga , Ebstein Richard P.
Published: April 2007

The dopamine D4 receptor (DRD4), a well‐characterized, polymorphic gene, is an attractive candidate for contributing risk to disordered eating and anorexia nervosa (AN). We tested association using UNPHASED for 5 DRD4 polymorphic loci, 3 promoter region SNPs (C‐521T, C‐616G, A‐809G), the 120 bp promoter region tandem duplication and the exon III repeat, in 202 AN trios and 418 control families. Since perfectionism characterizes AN, we tested these five loci for association with the Child and Adolescent Perfectionism Scale (CAPS) in the AN and control groups. Single locus analysis showed significant association between the ‘C’ C‐521T allele and AN. Haplotype analysis also showed significant association, particularly a 4‐locus haplotype (exon III&120 bp repeat&C‐521T&A‐809G). Association was also observed between DRD4 and CAPS scores both for AN and control subjects. The insulin‐like growth factor 2 (IGF2) and the arginine vasopressin 1a receptor (AVPR1a), previously shown to be associated with disordered eating, were also associated with CAPS scores. Three genes associated with AN were also associated with perfectionism. Personality traits are potential endophenotypes for understanding the etiology of eating disorders and one of the several pathways to eating pathology may be mediated by the impact of DNA sequences on perfectionism. © 2007 Wiley‐Liss, Inc.
Twenty‐five years of end‐user searching, Part 1: Research findings
Authors: Markey Karen
Published: April 2007

This is the first part of a two‐part article that reviews 25 years of published research findings on end‐user searching in online information retrieval (IR) systems. In Part 1 (Markey, 2007), the author seeks to answer the following questions: What characterizes the queries that end users submit to online IR systems? What search features do people use? What features would enable them to improve on the retrievals they have in hand? What features are hardly ever used? What do end users do in response to the system's retrievals? Are end users satisfied with their online searches? Summarizing searches of online IR systems by the search features people use everyday makes information retrieval appear to be a very simplistic one‐stop event. In Part 2, the author examines current models of the information retrieval process, demonstrating that information retrieval is much more complex and involves changes in cognition, feelings, and/or events during the information seeking process. She poses a host of new research questions that will further our understanding about end‐user searching of online IR systems.
Novel amphiphilic ternary polysaccharide derivates chitosan‐g‐ PCL‐b‐MPEG: Synthesis, characterization, and aggregation in aqueous solution
Authors: Lu Yiye , Liu Li , Guo Shengrong
Published: April 2007

Chitosan‐g‐PCL‐b‐MPEG copolymers of various compositions were successful synthesized via a protection‐graft‐deprotection procedure, by the esterification of phthaloyl‐protected chitosan (PHCS) with MPEG‐b‐PCL‐COOH, which was synthesized from MPEG and ε‐caprolactone and carboxylated by maleic anhydride. The chemical structure of the chitosan‐g‐PCL‐b‐MPEG was characterized by Fourier transform infrared and NMR spectroscopy. The chitosan‐g‐PCL‐b‐MPEG was obtained as amphoteric hybrid with amino polysaccharide backbone and amphiphilic MPEG‐b‐PCL side chain. Their crystallinity and aggregation behavior in aqueous solution were also investigated. © 2007 Wiley Periodicals, Inc. Biopolymers 86: 403–408, 2007.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Hormonal imprinting: phylogeny, ontogeny, diseases and possible role in present‐day human evolution
Authors: Csaba G.
Published: April 2007

Hormonal (chemical) imprinting which was first observed (and named) by us in the seventies of the last century, is a general biological phenomenon which takes place when the developing receptor meets its target hormone for the first time. Under the effect of imprinting, receptors mature and reach their maximal binding capacity. It also influences the cells' hormone production and different functions depending on receptors and hormones. Hormonal imprinting is present already at the unicellular level causing the development of specific receptors and helping the easier recognition of useful or harmful surrounding molecules. The phenomenon is an important factor in the survival of the species, as the effect of imprinting is transmitted to the progeny cell generations. At the same time it possibly helps the selection of molecules which are suitable for acting as hormones in higher ranked animals. In mammals, hormonal imprinting takes place perinatally and determines the function of receptor‐signal‐transduction systems as well as hormone production for life. However, there are other critical imprinting periods for continuously developing cells. Excess of the target hormones or presence of foreign molecules which are able to bind to the receptors, provoke faulty imprinting in the critical periods with life‐long morphological, biochemical, functional or behavioural consequences. As many receptor‐bound foreign molecules are used as medical treatments and many such molecules are present around us and inside us as environmental pollutants, they—causing faulty imprinting—are able to predispose the (human) organism to cardiovascular, endocrine, metabolic and cancerous diseases. It seems likely that this effect is connected with disturbance of DNA methylation process in the critical periods of life. There are some signs of the transgenerational effect of faulty imprinting and this could be manifested in the evolution of humans by an epigenetic route. Copyright © 2007 John Wiley & Sons, Ltd.
Decreased serum dependence in the growth of NIH3T3 cells from the overexpression of human nuclear receptor‐binding SET‐domain‐containing protein 1 (NSD1) or fission yeast su(var)3‐9, enhancer‐of‐zeste, trithorax 2 (SET2)
Authors: Yamada‐Okabe Toshiko , Matsumoto Naomichi
Published: April 2007

Nuclear receptor‐binding SET‐domain‐containing protein 1 (NSD1), a culprit gene for Sotos syndrome, contains a su(var)3‐9, enhancer‐of‐zeste, trithorax (SET) domain that is responsible for histone methyltransferase activity and other domains such as plant homeodomain (PHD) and proline‐tryptophan‐tryptophan‐proline (PWWP) involved in protein–protein interactions in the C‐terminal half of NSD1. To elucidate the function of NSD1 on cell growth, we overexpressed NSD1 in NIH3T3 cells. Cells overexpressing NSD1 grew in the presence of 2% serum, whereas vector transfected cells did not. Overexpression of the C‐terminal half of NSD1 but not the N‐terminal half of NSD1 also produced cell growth under low serum concentration. Furthermore, overexpression in NIH3T3 of Schizosaccharomyces pombe SET2 which has a SET domain but not PHD or PWWP domains conferred the reduced serum dependence. Thus, the SET domain of NSD1 is involved in cell growth by modulating serum dependence. Copyright © 2007 John Wiley & Sons, Ltd.
Ligand‐Induced Folding of the Adenosine Deaminase A‐Riboswitch and Implications on Riboswitch Translational Control
Authors: Rieder Renate , Lang Kathrin , Graber Dagmar , Micura Ronald
Published: April 2007

By using a structure‐based fluorescence spectroscopic approach, we have examined the folding of an adenine‐responsive riboswitch that regulates translation initiation. We observed adaptive recognition of the ligand for the aptamer domain of adenosine deaminase (add) mRNA from Vibrio vulnificus, and revealed pronounced conformational changes even in the preorganized loop–loop region that is distant from the binding site. Importantly, the full‐length riboswitch domain, which has a potential translational repressor stem is able to form a binary complex with adenine, and does not act as a folding trap to inhibit binding. The aptamer that is extended by the expression platform therefore remains fully responsive to its ligand; this is in contrast to the previously investigated pbuE A‐riboswitch, which becomes trapped in a nonresponsive terminator fold. Consequently, the latter must employ complex response mechanisms, such as operating in kinetic‐control mode or using transcriptional pausing, to provide time for the aptamer portion to fold and to bind. The different behavior of the riboswitches can be rationalized by their distinct sequence interface between the aptamer and expression platform. For the add A‐riboswitch, our data suggest a thermodynamically driven response mechanism.
Chaos theory in chemistry and chemometrics: a review
Authors: Cramer Jeffrey A. , Booksh Karl S.
Published: April 2007

Since the initial development of chaos theory and corollary concepts such as the strange attractor and fractal dimensionality, there has been a nontrivial effort to apply these concepts to the quantification of material and data structures. There exists within chaos theory modeling concepts that allow for thorough complexity analyses not available through alternate paradigms. The purpose of this paper is to review the main body of work that has been pursued in both experimental chemistry research and related data analysis development with respect to chaos theory and derivative ideas. Copyright © 2007 John Wiley & Sons, Ltd.
Study of Intramolecular Competition between Carboxylate and Phosphonate for PtII with the Aid of a Novel Tridentate Carboxylato‐Thioether‐Phosphonato Ligand
Authors: Hamel Matthieu , Rizzato Silvia , Lecinq Matthieu , Sène Aboubacary , Vazeux Michel , Gulea Mihaela , Albinati Alberto , Kozelka Jiří
Published: April 2007

The tridentate dianionic ligand 2‐[2′‐(hydroxyisopropoxyphosphoryl)phenylsulfanyl]benzoate (L2−) reacts with cis‐[Pt(NH3)2(H2O)2]2+ to form an S,O‐chelate in which the O‐coordinated group is either carboxylate or phosphonate, depending on the degree of protonation of the complex. Carboxylate appears to be the stronger ligand, and the stoichiometric reaction between cis‐[Pt(NH3)2(H2O)2]2+ and L2− yields the neutral species [Pt(L)(NH3)2], with L bound by sulfanyl and carboxylate groups, both in solution and in the solid state. Upon protonation of [Pt(L)(NH3)2], the stronger basicity of the carboxylate causes the Pt coordination to switch from carboxylate to phosphonate, and the uncoordinated carboxylate group becomes protonated. In methanolic solution, the first‐order kinetics of this rearrangement could be observed by 31P NMR spectroscopy. Both complexes—the carboxylate‐bound neutral complex [Pt(L)(NH3)2]⋅H2O (triclinic, P$\bar 1$ (no. 2), a=9.529(6), b=9.766(6), c=12.299(7) Å, α=106.91(2), β=101.71(2), γ=102.05(2)°, Z=2) and the perchlorate salt of the phosphonate‐bound complex [Pt(LH)(NH3)2]ClO4⋅H2O (monoclinic, P21/c (no. 14), a=12.095(2), b=14.046(2), c=14.448(2) Å, β=95.55(2)°, Z=4)—were characterized by X‐ray crystallography.
Total Synthesis of Potent Antifungal Marine Bisoxazole Natural Products Bengazoles A and B
Authors: Bull James A. , Balskus Emily P. , Horan Richard A. J. , Langner Martin , Ley Steven V.
Published: April 2007

The bengazoles are a family of marine natural products that display potent antifungal activity and a unique structure, containing two oxazole rings flanking a single carbon atom. Total syntheses of bengazole A and B are described, which contain a sensitive stereogenic centre at this position between the two oxazoles. Additionally, the synthesis of 10‐epi‐bengazole A is reported. Two parallel synthetic routes were investigated, relying on construction of the 2,4‐disubstituted oxazole under mild conditions and a diastereoselective 1,3‐dipolar cycloaddition. Our successful route is high yielding, provides rapid access to single stereoisomers of the complex natural products and allows the synthesis of analogues for biological evaluation.
Intramolecular Mixed‐Valence State Through Silicon or Germanium Double Bridges in Rigid Bis(Tetrathiafulvalenes)
Authors: Biaso Frédéric , Geoffroy Michel , Canadell Enric , Auban‐Senzier Pascale , Levillain Eric , Fourmigué Marc , Avarvari Narcis
Published: April 2007

The synthesis and characterization of two ortho‐dimethyltetrathiafulvalene (o‐DMTTF)‐based rigid dimers containing dimethylsilicon (Me2Si) or dimethylgermanium (Me2Ge) linkers are described. Single‐crystal X‐ray analysis reveals planar geometry for the central 1,4‐disilicon or 1,4‐digermanium six‐membered rings. DFT calculations provide optimized conformations in agreement with the experimental ones, and also emphasize the role of the heteroatomic linkers in the conjugation between the two redox active units. Cyclic voltammetry measurements show sequential oxidation into radical cation, and then dication species. Solution EPR measurements on the radical‐cation species indicate full delocalization of the unpaired electron over both electroactive TTF units, with an associated coupling of 0.42 G with twelve equivalent protons. DFT calculations afford fully planar geometry for the radical‐cation species and confirm the experimental isotropic coupling constant. Single‐crystal X‐ray analyses of two charge‐transfer compounds obtained upon chemical oxidation, formulated as [(Me2Si)2(o‐DMTTF)2]⋅1/2[TCNQ]⋅1/2[TCNQF4] and [(Me2Ge)2(o‐DMTTF)2]⋅[TCNQ], demonstrate the occurrence of genuine mixed‐valence radical‐cation species, as well as a three‐dimensional network of short S⋅⋅⋅S intermolecular contacts. Temperature‐dependent conductivity measurements demonstrate semiconducting behavior for both charge‐transfer compounds, with an increase of the absolute value of the conductivity upon applying external pressure. Band structure calculations reveal peculiar pseudo‐two‐dimensional electronic structures, also confirming electronic interactions through SiMe2 and GeMe2 bridges.
Kinetic Studies and Anaerobic Co‐digestion of Vegetable Market Waste and Sewage Sludge
Authors: Anhuradha S. , Vijayagopal V. , Radha P. , Ramanujam R.
Published: April 2007

The effect of anaerobic co‐digestion of vegetable market waste and sewage sludge was studied extensively. The effects of co‐digestion were compared with the separate digestion of vegetable market waste and sewage sludge. The batch studies were carried out using three bench scale reactors having 1.5 L working volume. The cumulative biogas production shows that the organic waste available from the vegetable waste contains easily biodegradable organic matter compared with the sewage sludge. First order reaction kinetics is maintained throughout the methanation fermentation. The reductions in volatile solids (VS) in the three reactors were in the range of 63–65 %. The specific gas production for vegetable waste was higher (0.75 L biogas/g VSin and 1.17 L biogas/g VSdes) than for the sewage sludge (0.43 L biogas/g VSin and 0.68 L biogas/g VSdes). Consequently, the specific gas production for the co‐digestion of the mixture of vegetable waste and sewage sludge (0.68 L biogas/g VSin and 1.04 L biogas/g VSdes) was considerably higher than for the sewage sludge only. Batch kinetics of anaerobic digestion is useful in predicting the performance of digesters and for the design of appropriate digesters.
On the Use of Venturi Tubes in Aeration
Authors: Baylar Ahmet , Ozkan Fahri , Unsal Mehmet
Published: April 2007

The ecological quality of water depends largely on the amount of oxygen that the water can hold. The higher the level of dissolved oxygen, the better the quality of a water system. By measuring dissolved oxygen, scientists determine the quality of water and health of an ecosystem. Oxygen enters water by entrainment of air bubbles. Many industrial and environmental processes involve the aeration of a liquid by such entrainment of air bubbles. Venturi aeration is a method of aeration that has become popular in recent years. When a minimal amount of differential pressure exists between the inlet and outlet sides of a venturi tube, a vacuum (air suction) occurs at the suction holes of the venturi tube. The present paper describes the effect of Reynolds Number, air inlet hole diameter, inlet diameter, pipe length, and angle of pipe downstream of the venturi tube, on the air injection rate. It is observed from the results that venturi tubes have high air injection efficiencies. Therefore, venturi tubes can be used as highly effective aerators in ponds, lakes, fish hatcheries, water treatment plants, etc.
Degree of Sulfate‐Reducing Activities on COD Removal in Various Reactor Configurations in Anaerobic Glucose and Acetate‐fed Reactors
Authors: Erdirencelebi Dilek , Ozturk Izzet , Ubay Cokgor Emine , Ubay Tonuk Gulseren
Published: April 2007

Sulfate‐reduction data from various anaerobic reactor configurations, e. g., upflow anaerobic sludge blanket reactor (UASBR), completely stirred tank reactor (CSTR), and batch reactor (BR) with synthetic wastewaters, having glucose and acetate as the substrates and different levels of sulfate, were evaluated to determine the level of sulfate‐reducing activity by sulfate‐reducing bacteria coupled to organic matter removal. Anaerobic reactors were observed for the degree of competition between sulfate‐reducing sulfidogens and methane producing bacteria during the degradation of glucose and acetate. Low sulfate‐reducing activity was obtained with a maximum of 20% of organic matter degradation with glucose‐fed upflow anaerobic sludge bed reactors (UASBRs), while a minimum of 2% was observed with acetate‐fed batch reactors. The highest sulfate removal performance (72–89%) was obtained from glucose fed‐UASB reactors, with the best results observed with increasing COD/SO4 ratios. UASB reactors produced the highest level of sulfidogenic activity, with the highest sulfate removal and without a performance loss. Hence, this was shown to be the optimum reactor configuration. Dissolved sulfide produced as a result of sulfate reduction reached 325 mg/L and 390 mg/L in CST and UASB reactors, respectively, and these levels were tolerated. The sulfate removal rate was higher at lower COD/SO4 ratios, but the degree of sulfate removal improved with increasing COD/SO4 ratios.
Experimental and Isothermal Studies on Sorption of Congo Red by Modified Mycelial Biomass of Wood‐rotting Fungus
Authors: Binupriya Arthur Raj , Sathishkumar Muthuswamy , Kavitha Dhamodaran , Swaminathan Krishnaswamy , Yun Sei‐Eok , Mun Sung‐Phil
Published: April 2007

Batch biosorption experiments were carried out for the removal of Congo red from aqueous solution using native and pretreated mycelial pellets/biomass of Trametes versicolor. The effect of process parameters such as contact time, dye concentration, and pH on the extent of Congo red biosorption has been investigated. Higher dye concentrations resulted in lower biosorption. Increases in biomass dosage led to increases in the levels of biosorption. Biosorption kinetics and equilibrium data are essential basic requirements to develop an effective and accurate design model for the removal of the dye. A kinetic study showed that the biosorption of the dye on fungal biomass was a gradual process. Pseudo‐first‐order, pseudo‐second‐order, and Bangham's model were used to fit the experimental data. The results of the kinetic studies showed that the second‐order kinetic model fitted well for the present experimental data. Equilibrium isotherms were analyzed by Langmuir, Freundlich, Dubnin‐Radushkevich, and Temkin isotherms. The biosorption equilibrium data obeyed the Langmuir and Temkin isotherms well. Acidic pH was favorable for the biosorption of the dye. Studies on the pH effect and desorption show that chemisorption seems to play a major role in the biosorption process. Among the native and pretreated biomass studied, autoclaved biomass showed a better biosorption capacity.
Limited feasibility of double transplant in multiple myeloma
Authors: Corso Alessandro , Mangiacavalli Silvia , Barbarano Luciana , Alessandrino Emilio Paolo , Cairoli Roberto , Morra Enrica , Lazzarino Mario ,   on Behalf of the HOST Group
Published: April 2007

BACKGROUND.

Although high‐dose therapy is considered the standard therapy for younger patients with multiple myeloma (MM), the advantages of performing a second transplant remain debated. The current study was conducted to evaluate the efficacy and the feasibility of a front‐line double transplant program in young MM patients.

METHODS.

A total of 153 MM patients aged ≤65 years, the majority of whom had stage III disease (65%), were enrolled in a multicenter, nonrandomized, high‐dose program including 2 transplants.

RESULTS.

The percentage of good quality responses (complete and very good partial responses) increased from an initial 33% after induction to 91% (complete response rate of 29%) after 2 transplants. However, this increase in response did not produce an advantage in either event‐free survival or overall survival, even when the analysis was performed grouping patients by response. The protocol was well tolerated and no difference in transplant‐related mortality was observed between the first and second transplants. A first transplant was performed in 122 of 153 patients (80%), and 65 (42% of the enrolled patients) completed the double transplant program. Reasons for not undergoing the second autologous transplant were death (n = 2 patients), insufficient peripheral blood stem cells (n = 8 patients), severe transplant‐related toxicity (n = 10 patients), allotransplants (n = 9 patients), early progression after first transplant (n = 6 patients), lost to follow‐up (n = 3 patients), and patient refusal (n = 19 patients).

CONCLUSIONS.

Considering the limited advantage of double transplants, the complexity of the program, the high percentage of dropouts, and the additional costs of a second transplant, the current study favors single transplant programs for the treatment of younger MM patients. Cancer 2007. © 2007 American Cancer Society.
Upper and lower bounds for recurrent and recursively decomposable parallel processor‐networks
Authors: De La Torre Pilar , Kruskal Clyde P.
Published: April 2007

A “recursively decomposable network” can be partitioned into a finite number of subnetworks that are smaller “versions of itself,” where the subnetworks are themselves recursively decomposable. Several interesting notions of such networks emerge depending on the collections of parameters chosen to model the relative behavioral characteristics that make a subnetwork a version of another. Examples of such parameters are permutation time, bandwidth, latency, topology, wires, degree, and size. This paper introduces and studies the class of networks that are recursively decomposable relative to bandwidth limitations, and the subclass of “recurrent networks” that are recursively decomposable relative to topology limitations.

We show that an N‐node recursively decomposable into halves network with bandwidth‐inefficiency function β(x) must be at least \documentclass{article}\pagestyle{empty}\begin{document}$\frac{N}{2}\sum\nolimits_{i = l}^{\lg N}{\frac{1}{{\beta(2^i)}}}$\end{document} wires. This implies that the linear array, hypercube, and completely connected networks are all exactly optimal. The above lower bound is generalized to networks that are recursively decomposable, but not necessarily into halves. We show that the bound is tight up to a constant factor by exhibiting recurrent networks matching the above lower bounds.

Our lower bound results both tighten and generalize a result of Meertens: no recurrent, fixed degree network can permute in O(log N) time. © 1996 John Wiley & Sons, Inc. ©1996 John Wiley & Sons, Inc.
Global attractivity in a nonlinear second‐order difference equation
Authors: Kocic V. L. , Ladas G.
Published: April 2007

In this paper we obtain a global attractivity result for the positive equilibrium of a nonlinear second‐order difference equation of the form xn+1 = f(xn, xn+1), n = 0, 1, ⃛

The result applies to the difference equation xn+1 =A+bxn/A+n−1, n = 0, 1, ⃛

Where a, b, A ϵ (0, ∞). © 1996 John Wiley & Sons, Inc.
Solvable set/hyperset contexts: I. Some decision procedures for the pure, finite case
Authors: Omodeo Eugenio G. , Policriti Alberto
Published: April 2007

Hereditarily finite sets and hypersets are characterized both as algorithmic data structures and by means of a first‐order axiomatization which, despite being rather weak, suffices to make the following two problems decidable:

Establishing whether a conjunctionrof formulae of the form: ∀ y1⃛∀ ym((y1ϵW1& ⃛&ymϵWm) ←q), withqquantifier‐free and involving only the relators =, ϵ and propositional connectives, and eachyidistinct from allwj's, is satisfiable.

Establishing whether a formula of the form ∀y q, qquantifier‐free, is satisfiable.

Concerning (1), an explicit decision algorithm is provided; moreover, significantly broad subproblems of (1) are singled out in which a classification — that we call the ‘syllogistic decomposition’ ofr— of all possible ways of satisfying the input conjunctionrcan be obtained automatically. For one of these subproblems, carrying out the decomposition results in a finite family of syntactic substitutions that generate the space of all solutions tor. In this sense, one has a unification algorithm.

Concerning (2), a technique is provided for reducing it to a subproblem of (1) for which a decomposition method is available.

The algorithmic complexity of the problems under study is highlighted; a generalization of the decidability results to a theory where sets are blended with free Herbrand functors is announced. © 1996 John Wiley & Sons, Inc.
Bit‐parallel, free‐space, optical communication
Authors: Rudolph Larry
Published: April 2007

In this paper, we examine several issues of bit‐parallel free space optical communication such as arbitration operations, fault tolerance, and connector alignment. © 1996 John Wiley & Sons, Inc.
Robot motion planning
Authors: Sharir Micha
Published: April 2007

We survey recent developments in algorithmic motion planning in robotics. © 1996 John Wiley & Sons, Inc.
The murine allantois: emerging paradigms in development of the mammalian umbilical cord and its relation to the fetus
Authors: Inman Kimberly E. , Downs Karen M.
Published: April 2007

The fertilized egg of the mammal gives rise to the embryo and its extraembryonic structures, all of which develop in intimate relation with each other. Yet, whilst the past several decades have witnessed a vast number of studies on the embryonic component of the conceptus, study of the extraembryonic tissues and their relation to the fetus have been largely ignored. The allantois, precursor tissue of the mature umbilical cord, is a universal feature of all placental mammals that establishes the vital vascular bridge between the fetus and its mother. The allantois differentiates into the umbilical blood vessels, which become secured onto the chorionic component of the placenta at one end and onto the fetus at the other. In this way, fetal blood is channeled through the umbilical cord for exchange with the mother. Despite the importance of this vascular bridge, little is known about how it is made. The aim of this review is to address current understanding of the biology of the allantois in the mouse and genetic control of its features and functions, and to highlight new paradigms concerning the developmental relationship between the fetus and its umbilical cord. genesis 45: 237–258, 2007. Published 2007 Wiley‐Liss, Inc.
Photochemistry of trans‐ and cis‐[RuCl2(dmso)4] in Aqueous and Nonaqueous Solutions
Authors: Brindell Małgorzata , Stochel Grażyna , Bertolasi Valerio , Boaretto Rita , Sostero Silvana
Published: April 2007

The photochemical behavior of the trans‐ and cis‐[RuCl2(dmso)4] complexes has been investigated in organic coordinating solvents (dmso, CH3CN) and aqueous solutions by means of electronic and 1H NMR spectroscopy as well as chloride‐selective electrode measurements. Excitation in the UVA and visible region of the cis‐[RuCl2(dmso)4] complex in dmso leads to geometric isomerization with quantum yields Φ313 = 0.41 and Φ365 = 0.49 to give the photostable trans complex, whereas in acetonitrile and aqueous solutions, both isomerization and substitution processes occur. Moreover, in the latter two solvents, the trans isomer is photoactive and undergoes substitution reactions. In acetonitrile, for both trans‐ and cis‐[RuCl2(dmso)4] isomers, selective photolabilization of the dimethylsulfoxide ligands results in the formation of the trans‐[RuCl2(CH3CN)4] complex. In aqueous solutions, the dmso and Cl– ligands are gradually substituted by water molecules to give as a final product a mixture of(aqua)ruthenium(II) and (aqua)(chlorido)ruthenium(II) complexes. These species may prove to be useful in the binding of cellular components. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Solvent Control in the Protonation of [Cp*Mo(dppe)H3] by CF3COOH
Authors: Dub Pavel A. , Baya Miguel , Houghton Jennifer , Belkova Natalia V. , Daran Jean‐Claude , Poli Rinaldo , Epstein Lina M. , Shubina Elena S.
Published: April 2007

The outcome of the reaction between [Cp*Mo(dppe)H3] [dppe = 1,2‐bis(diphenylphosphanyl)ethane] and trifluoroacetic acid (TFA) is highly dependent on the solvent and the TFA/Mo ratio. The dihydride compound [Cp*Mo(dppe)H2(O2CCF3)] is obtained selectively when the reaction is carried out in aromatic hydrocarbons (benzene, toluene) when using less than one equivalent of TFA. The dihydride is also the end product when THF or MeCN are used as solvent, independent of the TFA/Mo ratio. In benzene/toluene the use of excess acid has a profound effect, resulting in the formation of the tetrahydrido complex [Cp*Mo(dppe)H4]+, which did not further evolve into the dihydrido product. Monitoring of the reaction by NMR and IR spectroscopy under different conditions (solvent, temperature, TFA/Mo ratio) reveals the rapid establishment of an equilibrium between the dihydrogen‐bonded adduct, [Cp*Mo(dppe)H3]···HO2CCF3, the ion‐paired proton‐transfer product, [Cp*Mo(dppe)H4]+···–O2CCF3, and the separated ions, followed by a slower irreversible transformation to the final dihydride product with H2 evolution. The activation parameters of the H2 evolution and M–OR product formation were determined. Excess TFA in low‐polarity solvents stabilizes the separated charged species by forming the homoconjugate anion [CF3COO(CF3COOH)n]–. The effect of the solvent on the course of the reaction can be interpreted in terms of the different polarity, H‐bonding ability, and coordinating power of the various solvent molecules.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Asymmetric 1,3‐Dipolar Cycloaddition Reactions of Benzonitrile Oxide Mediated by a Chiral Lewis Acid
Authors: Yamamoto Hidetoshi , Hayashi Saori , Kubo Masashi , Harada Mayu , Hasegawa Masayuki , Noguchi Michihiko , Sumimoto Michinori , Hori Kenzi
Published: April 2007

In this paper we report on the asymmetric 1,3‐dipolar cycloaddition reactions of nitrile oxides mediated by pybox/ytterbium triflates, ‐/magnesium bromide, and ‐/magnesium perchlorate. It was confirmed that the reactions proceed smoothly to give isoxazoline derivatives in high enantiomeric excesses with Mg2+ or Yb3+ complexes and acrylamide dipolarophiles bearing an oxazolidinone or imidazolidinone coordination auxiliary as well as a pybox ligand. In reactions with a dipolarophile bearing 4,4‐dimethyloxazolidinone as the coordination auxiliary, an enantiomeric excess (59 % ee) of the corresponding cycloaddition product was achieved by using a slow addition technique to generate nitrile oxides in the presence of Yb(OTf)3/ph‐pybox. The cycloaddition reaction of a dipolarophile with an unsubstituted oxazolidinone group in the presence of Yb(OTf)3/ph‐pybox at a relatively high temperature (35 °C) produced a higher enantiomeric excess. A relatively low temperature (–78 °C) was required to obtain enantiomeric excesses such as 69 and 87 % ee in the reactions of a dipolarophile bearing an imidazolidinone group to afford cycloadducts in the presence of MgBr2/ip‐pybox.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Allene Substitution‐Controlled Switching of Dimerization to Cycloisomerization in the PdII‐Catalyzed Reaction of Terminal α‐Allenones
Authors: Alcaide Benito , Almendros Pedro , Martínez del Campo Teresa
Published: April 2007

In this contribution, we describe the role of steric interactions in PdII‐catalyzed reactions of terminal α‐allenones, which has not previously been invoked in discussions of these versatile compounds. By adopting [PdCl2(MeCN)2] as catalyst, the cycloisomerization/dimerization ratio of α‐allenones is controlled by the substitution of the allene compound: unsubstituted allenones mainly afford dimerization, whereas allenones bearing an internal substituent favor the formation of cycloisomerization products. Thus, for the first time the mode of reaction (cycloisomerization vs. dimerization) of α‐allenones is substrate‐directable.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Anion Receptors Based on a Quinoline Backbone
Authors: Albrecht Markus , Triyanti  , Schiffers Stefanie , Osetska Olga , Raabe Gerhard , Wieland Thomas , Russo Luca , Rissanen Kari
Published: April 2007

2‐Amido‐8‐urea substituted quinoline derivatives are potent receptors for the binding of halide or benzoate anions in chloroform. The selectivity and affinity of the receptors for fluoride can be tuned by variation of the substituents at the receptor side chains. Computational considerations show that the cleft of the receptors provides space for effective binding of F–, but not bigger anions.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Electrochemical Properties of Electrode Modified with Langmuir‐Blodgett Film of p‐tert‐Butylcalix[4]arene Derivatives and Its Application in Determining of Silver
Authors: Wang Lu , Zhao Bang‐Tun , Ye Bao‐Xian
Published: April 2007

A new type of voltammetric sensor, Langmuir‐Blodgett (LB) film of 5,11,17,23‐tetra‐tert‐butyl‐25,27‐di(3‐thiadiazole‐propanoxy)‐26,28‐dihydroxycalix[4]arene modified glassy carbon electrode (LBTZCA–GCE), was prepared. The electrochemical properties of LBTZCA–GCE were researched in detail and its recognizing mechanism for silver ion in aqueous solution was discussed. Using this voltammetric sensor, a new stripping voltammetric method for determining of Ag+ was erected with good sensitivity, selectivity, reproducibility and recovery. The detection limit was 8×10−9 M at accumulation time of 180 s. By this method, real samples (lake water, tap water and synthesis sample) were analyzed and the results obtained were well satisfactory.
Cathedral Cave, Wellington Caves, New South Wales, Australia. A multiphase, non‐fluvial cave
Authors: Osborne R. A. L.
Published: April 2007

Cathedral Cave is an outstanding example of a class of multiphase caves with largely non‐fluvial origins. It contains large cavities such as cathedrals and cupolas, characteristic of excavation by convection currents in rising waters. Smaller‐scale features such as rising half‐tubes, pseudonotches, curved juts, projecting corners, blades and bridges indicate intersection and exhumation of older cavities during the formation of younger ones. It is possible to recognize at least ten significant phases of speleogenesis by morphostratigraphy, in addition to the four generations of cave‐filling palaeokarst deposits intersected by the cave. The cave we see today results from the progressive integration of a number of previously disconnected or poorly connected solution cavities. Copyright © 2007 John Wiley & Sons, Ltd.
A framework for stabilized partitioned analysis of thin membrane–wind interaction
Authors: Wüchner Roland , Kupzok Alexander , Bletzinger Kai‐Uwe
Published: April 2007

This contribution proposes a methodology for the numerical analysis and for the improvement of the design of free‐form membrane structures subjected to flow‐induced effects. Typical applications in such context are tents exposed to wind. Different physical factors connected to thin and flexible structures, highly turbulent air flows, as well as their interaction have to be taken into account. This necessitates the appropriate combination of different numerical disciplines which is done in the simulation of fluid–structure interaction. The over‐all complexity of the problem favours a modular and flexible software environment with a partitioned coupling strategy. Within such an environment, the solution of each physical and algorithmic field is applicable with the most suited method. In the proposed framework, the structural field is solved with the in‐house finite element program CARAT, which uses several finite element types and advanced solution strategies for form finding, nonlinear, and dynamical problems. The fluid field is solved with the CFD software package CFX‐5. The interaction between both physical fields is realized by the exchange of boundary conditions. Beyond the mere exchange of data, the utilization of stabilized as well as efficient coupling strategies is mandatory. This contribution illuminates the scope of numerical simulation theory and presents implementations followed by illustrative examples. Copyright © 2007 John Wiley & Sons, Ltd.
Fifth‐order Hermitian schemes for computational linear aeroacoustics
Authors: Capdeville G.
Published: April 2007

We develop a class of fifth‐order methods to solve linear acoustics and/or aeroacoustics. Based on local Hermite polynomials, we investigate three competing strategies for solving hyperbolic linear problems with a fifth‐order accuracy. A one‐dimensional (1D) analysis in the Fourier series makes it possible to classify these possibilities. Then, numerical computations based on the 1D scalar advection equation support two possibilities in order to update the discrete variable and its first and second derivatives: the first one uses a procedure similar to that of Cauchy–Kovaleskaya (the ‘Δ‐P5 scheme’); the second one relies on a semi‐discrete form and evolves in time the discrete unknowns by using a five‐stage Runge–Kutta method (the ‘RGK‐P5 scheme’). Although the RGK‐P5 scheme shares the same local spatial interpolator with the Δ‐P5 scheme, it is algebraically simpler. However, it is shown numerically that its loss of compactness reduces its domain of stability.

Both schemes are then extended to bi‐dimensional acoustics and aeroacoustics.

Following the methodology validated in (J. Comput. Phys. 2005; 210:133–170; J. Comput. Phys. 2006; 217:530–562), we build an algorithm in three stages in order to optimize the procedure of discretization.

In the ‘reconstruction stage’, we define a fifth‐order local spatial interpolator based on an upwind stencil. In the ‘decomposition stage’, we decompose the time derivatives into simple wave contributions.

In the ‘evolution stage’, we use these fluctuations to update either by a Cauchy–Kovaleskaya procedure or by a five‐stage Runge–Kutta algorithm, the discrete variable and its derivatives.

In this way, depending on the configuration of the ‘evolution stage’, two fifth‐order upwind Hermitian schemes are constructed.

The effectiveness and the exactitude of both schemes are checked by their applications to several 2D problems in acoustics and aeroacoustics. In this aim, we compare the computational cost and the computation memory requirement for each solution.

The RGK‐P5 appears as the best compromise between simplicity and accuracy, while the Δ‐P5 scheme is more accurate and less CPU time consuming, despite a greater algebraic complexity. Copyright © 2007 John Wiley & Sons, Ltd.
Gravity models of intra‐EU trade: application of the CCEP‐HT estimation in heterogeneous panels with unobserved common time‐specific factors
Authors: Serlenga Laura , Shin Yongcheol
Published: April 2007

We follow recent developments of panel data studies and allow for the existence of both observed and unobserved common factors where their individual responses are allowed to be heterogeneous. We then develop a generalized Hausman–Taylor estimation methodology, and apply our proposed estimation technique to an analysis of the gravity equation of bilateral trade flows among 15 European countries over 1960–2001. Empirical results demonstrate that our proposed approach provides more sensible results than the conventional approach based on fixed time dummies. These findings may highlight the importance of allowing for a certain degree of cross‐section dependence through unobserved heterogeneous time‐specific effects; the resulting estimates would otherwise be severely biased. Copyright © 2007 John Wiley & Sons, Ltd.
Evaluating the impacts of Washington state repeated job search services on the earnings of prime‐age female TANF recipients
Authors: Hsiao Cheng , Shen Yan , Wang Boqing , Weeks Greg
Published: April 2007

This paper uses an unbalanced panel dataset to evaluate how repeated job search services (JSS) and other personal characteristics affect the quarterly earnings of the prime‐age female welfare recipients in the State of Washington. We propose a joint dependent framework for the probability of employment and potential earnings or hours or hourly wage rates to facilitate the investigation of the issues of joint determination of employment and potential earnings and to allow for factors to have different impacts on employment status and on quarterly earnings. We have also suggested formulae to compute the dynamic impact of JSS on duration and earnings. Both the maximum likelihood (ML) and semi‐parametric estimates are provided. We find that the results are sensitive to the choice of models and estimation methods. For a randomly assigned individual, the first, second and three or more JSS raised the short‐run and long‐run earnings by (5%, 0%, 0%) and (1%, 0%, 0%), respectively, based on the MLE, and by (56.6%, 36.2%, 36.9%) and (50.7%, 36.2%, 36.9%), respectively, based on the semi‐parametric Tobit model. We have also conducted specification analysis. The results appear to favor semi‐parametric Type II Tobit model estimates. Copyright © 2007 John Wiley & Sons, Ltd.
Panel unit root tests and spatial dependence
Authors: Baltagi Badi H. , Bresson Georges , Pirotte Alain
Published: April 2007

This paper studies the performance of panel unit root tests when spatial effects are present that account for cross‐section correlation. Monte Carlo simulations show that there can be considerable size distortions in panel unit root tests when the true specification exhibits spatial error correlation. These tests are applied to a panel data set on net real income from the 1000 largest French communes observed over the period 1985–1998. Copyright © 2007 John Wiley & Sons, Ltd.
Disruption of FRNK expression by gene targeting of the intronic promoter within the focal adhesion kinase gene
Authors: Hayasaka Haruko , Martin Karen H. , Hershey E. Daniel , Parsons J. Thomas
Published: April 2007

FRNK, a non‐catalytic variant of focal adhesion kinase (FAK), is expressed in major blood vessels throughout mouse development and is postulated to play a role in regulating cell adhesion and signaling in vascular smooth muscle cells (VSMCs). The FRNK transcriptional start site lies within an intron of the FAK gene, suggesting that the FRNK gene is a “gene within a gene”. Here, we identified a 1 kb intronic sequence of the FAK gene that is necessary for endogenous FRNK expression. Deletion of this sequence in gene‐targeted mice abolished FRNK expression, showing the direct involvement of the FAK intron in the regulation of FRNK expression. The level of FAK expression was normal in the FRNK‐deficient mice, indicating that FAK and FRNK are transcriptionally regulated by distinct promoters. The FRNK‐deficient mice were viable, fertile, and displayed no obvious histological abnormalities in any of the major blood vessels. Western blot analysis showed that FRNK–deficient and wild‐type (WT) cells had comparable levels of steady‐state and adhesion‐dependent FAK autophosphorylation. Despite the fact that ectopic expression of FRNK suppresses focal adhesion formation in cultured cells, these results suggest that endogenous FRNK is not essential for development or the formation of the mouse vasculature. J. Cell. Biochem. 102: 947–954, 2007. © 2007 Wiley‐Liss, Inc.