bluuebunny/crossref_metadata_2025 huggingface dataset:
A fracture‐mechanics‐based approach to fracture control in biomedical devices manufactured from superelastic Nitinol tube
Authors: Robertson S. W. , Ritchie R. O.
Published: May 2007

Several key fracture‐mechanics parameters associated with the onset of subcritical and critical cracking, specifically the fracture toughness, crack‐resistance curve, and fatigue threshold, have recently been reported for the superelastic alloy Nitinol, in the product form of the thin‐walled tube that is used to manufacture several biomedical devices, most notably endovascular stents. In this study, we use these critical parameters to construct simple decision criteria for assessing the quantitative effect of crack‐like defects in such Nitinol devices with respect to their resistance to failure by deformation or fracture. The criteria are based on the (equivalent) crack‐initiation fracture toughness and fatigue threshold stress‐intensity range, together with the general yield strength and fatigue endurance strength, and are used to construct a basis for design against single‐event (overload) failures as well as for time‐/cycle‐delayed failures associated with fatigue. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2008
Interaction of cells and nanofiber scaffolds in tissue engineering
Authors: Venugopal J. , Low Sharon , Choon Aw Tar , Ramakrishna S.
Published: May 2007

Nanofibers and nanomaterials are potentially recent additions to materials in relation to tissue engineering (TE). TE is the regeneration of biological tissues through the use of cells, with the aid of supporting structures and biomolecules. Mimicking architecture of extracellular matrix is one of the challenges for TE. Biodegradable biopolymer nanofibers with controlled surface and internal molecular structures can be electrospun into mats with specific fiber arrangement and structural integrity for drug delivery and TE applications. The polymeric materials are widely accepted because of their ease of processability and amenability to provide a large variety of cost‐effective materials, which help to enhance the comfort and quality of life in modern biomedical and industrial society. Today, nanotechnology and nanoscience approaches to scaffold design and functionalization are beginning to expand the market for drug delivery and TE is forming the basis for highly profitable niche within the industry. This review describes recent advances for fabrication of nanofiber scaffolds and interaction of cells in TE. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2008
Should in the treatment of osteochondritis dissecans biodegradable or metallic fixation devices be used? A comparative study in goat knees
Authors: Wouters Diederick B. , Bos Rudolf R. M. , van Horn Jim R. , van Luyn Marja J. A.
Published: May 2007

Most of the metallic devices have to be removed, treating osteochondritis dissecans lesions. This animal study describes the biological and mechanical behavior of screws and pins, made of commercially available PGA/PLA and PLA96 and metallic screws and pins, used for fragment fixation. A sham operation served as control. A tissue reaction with cavity formation was observed around every PGA/PLA screw, beginning at 12 weeks following insertion, in contrast to once around a PLA96 screw (p< 0.001), once around one of the 16 PGA/PLA pins and never around those, made of PLA96 (no significance). Disintegration of the PGA/PLA devices started 6 weeks following implantation against 34 weeks for the PLA96 implants. The gap between the fragment and the recipient cartilage disappeared only in the sham group. Many fragments of PGA/PLA material were found in the synovia, in contrast with just a few fragments in the PLA96 group, causing a mild cellular reaction. No polymer particles were found in the draining lymph nodes at any interval. In conclusion, the tested biodegradable screws should not be used for fragment fixation in the treatment of osteochondritis dissecans. Either an undesirable tissue reaction can be expected (PGAPLA), or, because of the slow degradation (PLLA), a screw might damage the opposite cartilage during weight bearing. Two biodegradable pins provide a safe rotational stability and should be combined with one metallic screw, providing compression. This screw has to be removed before loading the limb to prevent cartilage wear of the opposite tibia plateau. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2008
Cinnabarinic acid generated from 3‐hydroxyanthranilic acid strongly induces apoptosis in thymocytes through the generation of reactive oxygen species and the induction of caspase
Authors: Hiramatsu Rie , Hara Toshiaki , Akimoto Hidetoshi , Takikawa Osamu , Kawabe Tsutomu , Isobe Ken‐ichi , Nagase Fumihiko
Published: May 2007

3‐Hydroxyanthranilic acid (3HAA) is one of the tryptophan metabolites along the kynurenine pathway and induces apoptosis in T cells. We investigated the mechanism of 3HAA‐induced apoptosis in mouse thymocytes. The optimal concentration of 3HAA for apoptosis induction was 300–500 µM. The induction of apoptosis by a suboptimal concentration (100 µM) of 3HAA was enhanced by superoxide dismutase (SOD) as well as MnCl2 and further promoted in the presence of catalase. The 3HAA‐mediated generation of intracellular reactive oxygen species (ROS) was enhanced by SOD or MnCl2 and inhibited by catalase. Corresponding to apoptosis induction, the generation of cinnabarinic acid (CA) through the oxidation of 3HAA was enhanced by SOD or MnCl2 in the presence of catalase. The synthesized CA possessed more than 10 times higher apoptosis‐inducing activity than 3HAA. The intracellular ROS generation was induced by CA within 15 min and decreased to the control levels within 4 h, whereas the 3HAA‐induced ROS generation increased gradually up to 4 h. Corresponding to ROS generation, the mitochondrial membrane potential was downregulated within 15 min and retained by the CA treatment. Apoptosis induction by 3HAA or CA was dependent on caspases, and caspase‐3 was much more strongly activated by CA than 3HAA. In conclusion, the CA generated from 3HAA possesses a strong apoptosis‐inducing activity in thymocytes through ROS generation, the loss of mitochondrial membrane potential, and caspase activation. J. Cell. Biochem. 103: 42–53, 2008. © 2007 Wiley‐Liss, Inc.
A novel semi‐empirical topological descriptor Nt and the application to study on QSPR/QSAR
Authors: Zhou Congyi , Nie Changming , Li Shan , Li Zhonghai
Published: May 2007

A novel semi‐empirical topological descriptor Nt was proposed by revising the traditional distance matrix based on the equilibrium electronegativity and the relative bond length. Nt can not only efficiently distinguish structures of organic compounds containing multiple bonds and/or heteroatoms, but also possess good applications of QSPR/QSAR (quantitative structure‐property/activity relationships) to a large diverse set of compounds, which are alkanes, alkenes, alkynes, aldehydes, ketones, thiols, and alkoxy silicon chlorides with all the correlation coefficients of the models over 0.99. The LOO CV (leave‐one‐out cross‐validation) method was used to testify the stability and predictive ability of the models. The validation results verify the good stability and predictive ability of the models employing the cross‐validation parameters: RCV, SEPCV and SCV, which demonstrate the wide potential of the Nt descriptor for applications to QSPR/ QSAR. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007
A systematic quantum chemical investigation of the CH bond activation in methane by gas phase vanadium oxide cation VO+
Authors: Pykavy Mikhail , Van Wüllen Christoph
Published: May 2007

The interaction between a methane molecule and the VO+ cation in the gas phase has been investigated by means of single reference density functional (B3LYP) and wave function‐based multireference (MR) correlation calculations. For the latter, an extrapolation technique is used to evaluate correlation energies at the basis set limit. A comprehensive picture for the CH activation features a variety of molecular structures corresponding to both minima and transition states. Possible reaction paths are discussed, also taking into account change of the spin multiplicity. Activation of the methane molecule by VO+ is always an endothermic process. Competing reaction paths might be expected. An evaluation of miscellaneous computational methods is performed using calculated energy differences for various molecular structures. Results obtained from the MR calculations exhibit no systematic convergence with increasing size of the active space used, and for two largest active spaces relative energies still differ by up to 25 kJ/mol. Simple mean difference between the B3LYP results and the best MR values is −50 ± 19 kJ/mol. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007
Model transition states for methane diazonium ion methylation of guanine runs in oligomeric DNA
Authors: Ekanayake Kaushalya S. , Lebreton Pierre R.
Published: May 2007

The DNA reaction pattern of the methane diazonium ion, which is the reactive intermediate formed from several carcinogenic methylating agents, was examined at N7 and O6 sites in guanine runs occurring in oligonucleotides and model oligonucleotides. Density functional B3LYP/6‐31G*, and SCF 3‐21G and STO‐3G energies of model transition states were calculated in the gas phase and in the CPCM reaction field. For nucleotides containing two, three, and four stacked guanines with counterions in the gas phase, O6 reactivity is greater than N7 reactivity. In the reaction field, N7 reactivity is 9.0 to 9.8 times greater than O6 reactivity. For a double‐stranded oligonucleotide containing two stacked guanines with counterions in the reaction field, the N7 and O6 reactivities of the 3′‐guanine are 3.9 times greater than the corresponding sites in the 5′‐guanine. For double‐stranded oligonucleotides with three or four stacked guanines and counterions, the reactivities of the interior guanines are higher than corresponding reactivities of guanines at the ends. These reaction patterns agree with most of the available experimental data. Activation energy decomposition analysis for gas‐phase reactions in a double‐stranded dinucleotide containing two stacked guanines with counterions indicates that selectivity at O6 is almost entirely due to electrostatic forces. Selectivity at N7 also has a large electrostatic interaction. However, the orbital interaction also contributes significantly to the gas‐phase selectivity, accounting for 32% of the total interaction energy difference between the 3′‐ and 5′‐guanine reactions. In aqueous solution, the relative orbital contribution to N7 selectivity is likely to be larger. © 2007 Wiley Periodicals, Inc. J Comput Chem 2007
Windock: Structure‐based drug discovery on windows‐based PCs
Authors: Hu Zengjian , Southerland William
Published: May 2007

In recent years, virtual database screening using high‐throughput docking (HTD) has emerged as a very important tool and a well‐established method for finding new lead compounds in the drug discovery process. With the advent of powerful personal computers (PCs), it is now plausible to perform HTD investigations on these inexpensive PCs. To make HTD more accessible to a broad community, we present here WinDock, an integrated application designed to help researchers perform structure‐based drug discovery tasks under a uniform, user friendly graphical interface for Windows‐based PCs. WinDock combines existing small molecule searchable three‐dimensional (3D) libraries, homology modeling tools, and ligand‐protein docking programs in a semi‐automatic, interactive manner, which guides the user through the use of each integrated software component. WinDock is coded in C++. © 2007 Wiley Periodicals, Inc. J Comput Chem 28: 2347–2351, 2007
Cytokine profile of human adipose‐derived stem cells: Expression of angiogenic, hematopoietic, and pro‐inflammatory factors
Authors: Kilroy Gail E. , Foster Sandra J. , Wu Xiying , Ruiz Joseph , Sherwood Sonya , Heifetz Aaron , Ludlow John W. , Stricker Dawn M. , Potiny Suma , Green Patrick , Halvorsen Yuan‐Di C. , Cheatham Bentley , Storms Robert W. , Gimble Jeffrey M.
Published: May 2007

Adipose tissue serves as a source of adipokines and cytokines with both local and systemic actions in health and disease. In this study, we examine the hypothesis that multipotent human adipose‐derived stem cells (ASCs), capable of differentiating along the adipocyte, chondrocyte, and osteoblast pathways, contribute to adipose tissue‐derived cytokine secretion. Following exposure to basic fibroblast growth factor (bFGF) or epidermal growth factor (EGF), the ASCs significantly increase their secretion of hepatocyte growth factor (HGF), a cytokine implicated in hematopoiesis, vasculogenesis, and mammary epithelial duct formation. Ascorbic acid synergizes with these inductive factors, further increasing HGF levels. Following exposure to lipopolysaccharide, ASCs increase their secretion of both hematopoietic (granulocyte/monocyte, granulocyte, and macrophage colony stimulating factors, interleukin 7) and proinflammatory (interleukins 6, 8, and 11, tumor necrosis factor α) cytokines based on ELISA and RT‐PCR. In co‐cultures established with umbilical cord blood‐derived CD34+ cells, the ASCs support long‐term hematopoiesis in vitro. Furthermore, in short‐term 12‐day co‐cultures, the ASC maintain and expand the numbers of both myeloid and lymphoid progenitors. These observations are consistent with the functionality of the secreted cytokines and confirm recent reports by other laboratories concerning the hematopoietic supportive capability of ASCs. We conclude that the ASCs display cytokine secretory properties similar to those reported for bone marrow‐derived mesenchymal stem cells (MSCs). J. Cell. Physiol. 212:702–709, 2007. © 2007 Wiley‐Liss, Inc.
Regulation of Na,K‐ATPase α1 subunit gene transcription in response to low K+: Role of CRE/ATF‐ and GC box‐binding proteins
Authors: Wang Gang , Kawakami Kiyoshi , Gick Gregory
Published: May 2007

Na,K‐ATPase expression is upregulated in mammalian cells as a consequence of persistent inhibition of Na,K‐ATPase enzymatic activity by low external K+. We previously demonstrated that exposure of neonatal rat cardiac myocytes to low K+ increased Na,K‐ATPase α1 subunit mRNA content and promoter activity. In this work, we utilized transient transfection studies with rat Na,K‐ATPase α1 subunit 5′‐flanking region deletion plasmids to identify DNA sequences required for low K+‐mediated stimulation of α1 subunit promoter expression in cardiac myocytes. Maximal low K+‐responsiveness of the α1 promoter was found to be dependent on nucleotides from −102 to −62 and a downstream region from +53 to +261. Further analysis of the upstream low K+‐responsive region using mutant constructs revealed that a CRE/ATF site at −70 to −63 and a GC box motif at −57 to −48 were both required for the effect of low K+ on α1 subunit gene transcription. Electrophoretic mobility shift assays revealed that low K+ increased binding of transcription factors to the GC box and, to a lesser extent, to the CRE/ATF site. Western blot analysis demonstrated that exposure of cardiac myocytes to low K+ resulted in increased nuclear content of Sp1, Sp3 and CREB‐1. Finally, a selective increase in phosphorylation of Sp1 was found in nuclear extracts from low K+‐treated cells. We conclude that low K+‐mediated upregulation of Na,K‐ATPase α1 subunit gene expression in neonatal rat cardiac myocytes is dependent, in part, on CRE/ATF‐ and GC box‐binding transcription factors. J. Cell. Physiol. 213: 167–176, 2007. © 2007 Wiley‐Liss, Inc.
Differential gene expression induction by TRAIL in B chronic lymphocytic leukemia (B‐CLL) cells showing high versus low levels of Zap‐70
Authors: Secchiero Paola , di Iasio Maria Grazia , Gonelli Arianna , Barbarotto Elisa , Melloni Elisabetta , Tiribelli Mario , Chiaruttini Cristina , Zauli Giorgio
Published: May 2007

Among 14 peripheral blood samples obtained from patients affected by B chronic lymphocytic leukemia (B‐CLL) at initial stages (Rai 0–1) of the disease, 6 showed intermediate/high levels of Zap‐70 while 8 displayed low/absent levels of Zap‐70. Although Zap‐70high and Zap‐70low B‐CLL samples displayed similar levels of surface death receptor TRAIL‐R2, recombinant TRAIL induced cytotoxicity only in a subset of Zap‐70low B‐CLL samples while Zap‐70high were completely resistant to TRAIL. The gene expression profiling was next analyzed in all B‐CLL samples treated with either chlorambucil or recombinant TRAIL. While chlorambucil up‐regulated the steady‐state mRNA levels of known p53 target genes, such as PUMA, Fas/CD95 and MDM2 in all B‐CLL samples examined, it significantly down‐regulated survivin in Zap‐70low but not in Zap‐70high. On the other hand, recombinant TRAIL up‐regulated the expression of several cytokines (IL‐1β, IL‐1α, IL‐8), which have been involved in promoting B‐CLL cell survival. In particular, TRAIL selectively up‐regulated IL‐1β in Zap‐70low B‐CLL samples, while it markedly and selectively up‐regulated its own mRNA and that of cyclooxigenase‐2 (COX‐2) in Zap‐70high. Taken together, our findings suggest that a significant expression of Zap‐70 modulate the response of B‐CLL to TRAIL, which might represents an initial step in the pathogenesis of B‐CLL. J. Cell. Physiol. 213: 229–236, 2007. © 2007 Wiley‐Liss, Inc.
PIM‐2 is an independent regulator of chondrocyte survival and autophagy in the epiphyseal growth plate
Authors: Bohensky Jolene , Shapiro Irving M. , Leshinsky Serge , Watanabe Hitoshi , Srinivas Vickram
Published: May 2007

The overall goal of the investigation was to examine the activity and role of the PIM serine/threonine protein kinases in the growth plate. We showed for the first time that PIM‐2 was highly expressed in epiphyseal chondrocytes and that the kinase was required for critical activities linked to cell survival. These activities were independent of those mediated by Akt‐1. It was noted that PIM‐2 protected chondrocytes from rapamycin sensitized (TOR inhibited) cell death. Since inhibition of mTOR caused autophagy, we examined the autophagic response of PIM‐2 silenced cells. We showed that PIM‐2 promoted expression and organization of autophagic proteins LC3, and Beclin‐1 and enhanced lysosomal acidification. At the same time, PIM‐2 modulated the activity of a key regulator of apoptosis, BAD. Since BAD inhibition and Beclin‐1 expression activated autophagy, it is likely that induction of the autophagic pathway would serve to inhibit apoptosis and preserve the life of the terminally differentiated chondrocyte. We conclude that PIM‐2 regulates a new intermediate stage in the differentiation pathway, the induction of autophagy. J. Cell. Physiol. 213: 246–251, 2007. © 2007 Wiley‐Liss, Inc.
Methylation suppresses the proteasome‐inhibitory function of green tea polyphenols
Authors: Landis‐Piwowar Kristin R. , Wan Sheng Biao , Wiegand Richard A. , Kuhn Deborah J. , Chan Tak Hang , Dou Q. Ping
Published: May 2007

Under physiological conditions, biotransformation reactions, such as methylation, can modify green tea polyphenols (GTPs) and therefore limit their in vivo cancer‐preventive activity. Although a recent study suggested that methylated polyphenols are less cancer‐protective, the molecular basis is unknown. We previously reported that ester bond‐containing GTPs, for example (−)‐epigallocatechin‐3‐gallate [(−)‐EGCG] or (−)‐epicatechin‐3‐gallate [(−)‐ECG], potently and specifically inhibit the proteasomal chymotrypsin‐like activity. In this study, we hypothesize that methylated GTPs have decreased proteasome‐inhibitory abilities. To test this hypothesis, methylated (−)‐EGCG and (−)‐ECG analogs that can be found in vivo were synthesized and studied for their structure‐activity relationships (SARs) using a purified 20S proteasome. The addition of a single methyl group on (−)‐EGCG or (−)‐ECG led to decreased proteasome inhibition and, as the number of methyl groups increased, the inhibitory potencies further decreased. These SARs were supported by our findings from in silico docking analysis published recently. Previously, we synthesized a peracetate‐protected (−)‐EGCG molecule, Pro‐EGCG (1), to enhance its cellular permeability and stability, and current HPLC analysis confirms conversion of Pro‐EGCG (1) to (−)‐EGCG in cultured human leukemic Jurkat T cells. Furthermore, in this study, peracetate‐protected forms of methylated GTPs were added in intact Jurkat T cells to observe the intracellular effects of methylation. Peracetate‐protected, monomethylated (−)‐EGCG induced greater cellular proteasome inhibition and apoptosis than did peracetate‐protected, trimethylated (−)‐EGCG, consistent with the potencies of the parent methylated analogs against a purified 20S proteasome. Therefore, methylation on GTPs, under physiological conditions, could decrease their proteasome‐inhibitory activity, contributing to decreased cancer‐preventive effects of tea consumption. J. Cell. Physiol. 213: 252–260, 2007. © 2007 Wiley‐Liss, Inc.
Non‐essential dietary factors: from test tube to lifespan
Authors: Hillyard S Luke , German J Bruce
Published: May 2007

The agriculture and food industries have an opportunity to change the future of food production by providing foods containing non‐essential dietary factors (NEDFs) that improve health beyond a freedom from disease. In order to accomplish this in a safe and time‐effective manner, however, each NEDF needs to be tested on a number of levels before it is incorporated into foods. In vitro assays are useful for discovering potential beneficial NEDFS, but in vivo studies are needed to both confirm positive effects and to detect negative effects. The genetic and metabolic similarities between humans and Caenorhabditis elegans, combined with the ease with which this nematode can be manipulated in the laboratory make it an attractive candidate to fulfill the role of an early stage in vivo model. Measuring the lifespan of C. elegans cultured in the presence of a range of concentrations of a NEDF would be of both mechanistic and strategic value in identifying those NEDFs that warrant further testing. Copyright © 2007 Society of Chemical Industry
Is hepatic transplantation justified for primary liver cancer?
Authors: Fisher Robert A. , Maluf Daniel G. , Wolfe Luke , Williams Bridgette , Cotterell Adrian , Stravitz R. Todd , Heuman Douglas , Posner Marc
Published: May 2007

A concise, yet objective overview of Hepatocellular Carcinoma (HCC) treatment in 2006 with an intent to transplant is presented. The most significant variables impacting on the use of hepatic transplantation as therapy for primary liver cancer are developed under the headings of: Staging Criteria; Organ allocation; Transplant dropout minimization therapies; and Effects on the HCC general population. The pertinent medical literature and update of an ongoing intent‐to‐treat HCC with transplant single center randomized control trial are reviewed. J. Surg. Oncol. 2007;95:674–679. © 2007 Wiley‐Liss, Inc.
Measurement of limb volume: Laser scanning versus volume displacement
Authors: McKinnon John Gregory , Wong Vanessa , Temple Walley J. , Galbraith Callum , Ferry Paul , Clynch George S. , Clynch Colin
Published: May 2007

Background

Determining the prevalence and treatment success of surgical lymphedema requires accurate and reproducible measurement. A new method of measurement of limb volume is described.

Methods

A series of inanimate objects of known and unknown volume was measured using digital laser scanning and water displacement. A similar comparison was made with 10 human volunteers. Digital scanning was evaluated by comparison to the established method of water displacement, then to itself to determine reproducibility of measurement.

Results

(1) Objects of known volume: Laser scanning accurately measured the calculated volume but water displacement became less accurate as the size of the object increased. (2) Objects of unknown volume: As average volume increased, there was an increasing bias of underestimation of volume by the water displacement method. The coefficient of reproducibility of water displacement was 83.44 ml. In contrast, the reproducibility of the digital scanning method was 19.0 ml. (3) Human data: The mean difference between water displacement volume and laser scanning volume was 151.7 ml (SD ± 189.5). The coefficient of reproducibility of water displacement was 450.8 ml whereas for laser scanning it was 174 ml.

Conclusion

Laser scanning is an innovative method of measuring tissue volume that combines precision and reproducibility and may have clinical utility for measuring lymphedema. J. Surg. Oncol. 2007;96:381–388. © 2007 Wiley‐Liss, Inc.
Laser crystals and ceramics: recent advances
Authors: Kaminskii A.A.
Published: May 2007

After a brief examination of known insulating laser crystals and the stimulated emission channels of their generating activator ions, this article reviews recent advances in the development of novel lasing crystals and ceramics, as well as inorganic and organic nonlinear‐laser crystals for χ(3)and cascaded χ(3)↔ χ(2)frequency converters. Several new modern attractive technologies in the physics and techniques of crystalline lasers are also discussed.
On the Quasiasymptotic of Schwartz Distributions
Authors: Pilipovic Stevan
Published: May 2007

The quasiasymptotic of distributions with the supports in (0, ∞) was studied by the Soviet mathematicians Vladimirov, Drožinov and Zavialov in several papers. Some essential questions on the quasiasymptotic behaviour of Schwartz distributions defined on R are posed and answered in this paper.
On Interpolation Spaces with the Gelfand‐Phillips Property
Authors: Mastylo Mieczyslaw
Published: May 2007

In this paper we study interpolation spaces generated by some interpolation functors. We show that under some conditions for Banach couples X and Y the spaces dual to the orbits of elements are Gelfand—Philips spaces. Consequently, the ideal of nuclear operators from X to Y contains a copy of l1. We give also an interpolation theorem for limited operators.
Σ‐Groups as Convergence Groups
Authors: Higgs Denis
Published: May 2007

A Σ‐group is an abelian group in which certain infinite sums are postulated to exist and to satisfy axioms suggested by the properties of unconditional sums in abelian convergence groups. Two notions of convergence are considered: in terms of nets, and in terms of filters. It is proved that every Σ‐group can be regarded as a net convergence group (of a particular type). An example is given to show that the same does not remain true if filters are used instead of nets. For the special class of ‘adic’ Σ‐groups, however, it is proved that filters are adequate.
On Strong Versions of the Central Limit Theorem
Authors: Schatte Peter
Published: May 2007

Let Sn be the sum of n i.i.d.r.v. and let 1(‐∞,x)(·) be the indicator function of the interval (‐∞, x). Then the sequence 1(‐∞, x)(Sn/√n) does not converge for any x. Likewise the arithmetic means of this sequence converge only with probability zero. But the logarithmic means converge with probability one to the standard normal distribution Ø(x). Then for any bounded and a.e. continuous function a(y) the logarithmic means of a(Sn/√n) converge a.s. to a = ∫a(y)dØ(y). The arithmetic means of a(Snk/√n) converge to the same limit a for all subsequences nk = [ck], c > 1.
A Completion Functor for Ordered Cauchy Spaces
Authors: Kent D. C. , Vainio R.
Published: May 2007

A completion functor is constructed on a completion subcategory of the category of ordered CAUCHY spaces which preserves regularity, total boundedness, and uniformizability. Objects in the completion subcategory include the uniformizable ordered CAUCHY spaces and the c‐embedded CAUCHY spaces with discrete order.
Geometric Properties Characteristic of Normed Linear Space
Authors: Murphy Grattan , Freese Raymond , Andalafte Edward
Published: May 2007

This paper provides new characterizations of arbitrary, not necessarily rotund, normed linear spaces, using triangle median properties and weakened forms of associativity and the consistent midpoint property. Connections are explored between the methods used here and a characterization announced by ARONSZAJN in 1935.
On Smallest and Largest Orlicz Spaces
Authors: Hudzik Henryk
Published: May 2007

There are found the smallest and largest spaces among all ORLICZ spaces generated by non‐decreasing ORLICZ functions and also among all ORLICZ spaces generated by s‐convex ORLICZ functions, 0 < s ⩽ 1.
Estimates on the Spectrum of SCHRÖDINGER Operators with Attractive Boundary Conditions
Authors: Schröder Manfred
Published: May 2007

Estimates for the infimum of the spectrum of the Schrödinger operator HQu = ‐ Δu at a half space with boundary condition un = Qu (with un denoting the inner normal derivative of u, and Q being a real‐valued function defined at the boundary), and for the number resp. density of surface states of HQ, are presented.
Order‐Convergence in Posets
Authors: Fleischer Isidore
Published: May 2007

The kind of convergence induced in subsets of posets by order‐convergence is characterized: it is separated regular Fréchet filter convergence. An order‐convergence completion for posets and progroups is presented.
Manifolds with Cusps
Authors: Cromme Ludwig J.
Published: May 2007

In this paper manifolds with cusps are defined and their properties investigated. Manifolds with cusps are manifolds with boundary where the dimension of the tangent cone at points varies widely with that point. Examples are exponential sums, splines, and polynomials with only real roots. The investigations are motivated by numerical algorithms in approximation theory and other areas.
The Approximation Property for Nuclear Convergence Vector Spaces
Authors: Bjon Sten
Published: May 2007

Nuclear convergence spaces are studied. It is shown that an Le‐embedded convergence vector space E is LeLM‐embedded if it is Schwartz and satisfies a certain countability condition which expresses that the set of filters converging to zero is essentially countable. Further it is shown that if E is LeLM‐embedded and nuclear, then the identity E → E can be approximated with finite operators in the equable continuous convergence structure on L(E, E). This result is used in the study of the spectrum HomcHe(U) of the convergence algebra He(U) of holomorphic functions on a circled convex open set to prove sufficient conditions for the validity of the formula HomcHe(U) ∼ U.
[Russian Text Ignored]
Authors: [Russian Text Ignored]
Published: May 2007

[Russian Text Ignored].
A First Order Sufficient Condition for Optimality in Nonsmooth Optimization
Authors: Correa Rafaël , Hiriart‐Urruty Jean‐Baptiste
Published: May 2007

We derive a simple sufficient condition for a point a∈S⊂X be a local minimum of f: X → R on S. This condition is of the first order in its nature and takes into account the derivative (or some generalization of it) in a neighborhood of a. Applications like a sufficient condition for (a, b)∈ S × T ⊂ X × Y be a saddle‐point of a bivariate function f: X × Y ⊂ R are also proposed.
Strongly Cyclic Vectors for Partial Op*‐Algebras
Authors: Antoine J.‐P. , Inoue Atsushi
Published: May 2007

In this paper we define the notion of strongly cyclic vectors for partial Op*‐algebras. While such a notion has been considered in [1], the present one is more general and more useful in practice.
Shape as an Information‐Thermodynamical Concept and the Pattern Recognition Problem
Authors: Ingarden Roman S. , Górniewicz Lech
Published: May 2007

A hierarchical classification of different concepts of shape of compact connected sets inRn(topological, Lipshitz, homotopic, Borsuk an homological shapes) is given. The most general among them is the homological shape. There is only a countable number of homological shapes for connected compact sets inRn. In the casen= 2 even the number of different Borsuk shapes for connected compact sets is countable. Giving a probability distribution of shapes we can define a shape entropy, a mean shape and shape fluctuations. This enables a formulation of information thermodynamics of shape and its applications to different fields (physics – small systems, chemistry, biophysics, pattern recognition). The paper does not develop yet these applications, its aim is to clear the basic notions.
Partially Commutative Moment Problems
Authors: Borchers H. J. , Yngvason Jakob
Published: May 2007

Partially commutative tensor algebras occur naturally in the algebraic formulation of Wightman field theory. A state on an algebra of this type leads via GNS‐construction to a partially commutative family of hermitean operators on Hilbert space. We discuss the question when these operators can be extended to self adjoint operators preserving the commutation properties and state a necessary and sufficient condition for the existence of such an extension in terms of a positivity property of the state.
On Normal Bases for Finite Commutative Rings
Authors: Steidl Gabriele
Published: May 2007

This paper is devoted to the introduction of extension rings S : = R[x]/gR[x] with a suitable polynomial g ϵ R[x] of arbitrary commutative rings R with identity and to the development of a normal basis concept of S over R, which is similar to that of Galois extensions of finite fields. We prove new results for Galois extensions of local rings and apply them together with the Chinese remainder theorem to solve the above task in a constructive way.
One‐Parameter Groups Arising from Real Subspaces of Self‐Dual Hilbert W*‐Moduli
Authors: Frank Michael
Published: May 2007

The purpose of this paper is to generalize the results of M. A. Rieffel and A. van Daele [8, §§ 1, 2, 3] for Hilbert W*‐moduli over commutative W*‐Algebras. Some special real subspaces of such Hilbert W*‐moduli and the related operators are investigated. Particularly, the relation is established between *weakly continuous unitary one‐parameter groups of operators arising from them and the generalized K.M.S. condition. All key definitions are formulated without any commutativity supposition for the underlying W*‐algebra. The interpretation of these results is given for sets of continuous sections of “self‐dual” locally trivial Hilbert bundles over hyperstonian compact spaces. At the end of this paper some aspects of the general noncommutative case are discussed.
Isometries of a Space of Continuous Functions Determined by an Involution
Authors: Grzesiak Maciej
Published: May 2007

Let C(X, σ) be the space of all σ‐conjugate continuous complex functions, where σ is an involution on X. Surjective isometries of such spaces are investigated and a generalization of the Banach‐Stone theorem is proved.
Restricted Non‐Commutative Bernoulli Shifts
Authors: Quasthoff Uwe
Published: May 2007

Constructing non‐commutative Bernoulli shifts one starts with a measure theoretic Bernoulli shift and an equivalence relation on the measure space. There is a doubly infinite increasing sequence of measure preserving ergodic equivalence relations giving an increasing sequence of pairwise isomorphic von Neumann algebras invariant under the Bernoulli shift automorphism. We consider the index of Jones for those subalgebras and give an explicit example of conjugate non‐commutative Bernoulli shifts.
Probabilistic Proofs of Some Real Inversion Formulas
Authors: Teugels Jozef L.
Published: May 2007

We provide short probabilistic proofs for a number of new and known real inversion formulas for the Laplace and for the Stieltjes transform.
Oscillations of Higher Order Neutral Differential Equations with Variable Coefficients
Authors: Chuanxi Q. , Ladas G.
Published: May 2007

We obtain sufficient conditions for the oscillation of all solutions of the higher order neutral differential equation dn/dm[y(t) + P(t) y(t ‐ μ)] + Q(t) y(t −σ) = 0, t ≧ t0 where n ≧ 1, P ϵ C[t0, ∞), R], Q ϵ C[t0, ∞), R] and τ, μ ϵ R+.

Our results extend and improve several known results in the literature.
A Central Limit Theorem for the Weakly Asymmetric Simple Exclusion Process
Authors: Dittrich Peter , Gärtner Jürgen
Published: May 2007

We consider the one‐dimensional weakly asymmetric nearest neighbour exclusion process and study, in macroscopic space‐time coordinates, the fluctuations of the associated density field around the solution of the nonlinear BURGERS equation with viscosity. We show that this fluctuations converge to a generalized ORNSTEIN‐UHLENBECK process, the drift term of which can be obtained by linearization of the BURGERS equation. Our approach is based on a nonlinear transformation of the exclusion process.
Second‐order Characteristics for Stochastic Structures Connected with Gibbs Point Processes
Authors: Stoyan Dietrich , Grabarnik Pavel
Published: May 2007

The points of stationary and isotropic GIBBS point process are marked by exp(corresponding local energy). For the mean mark and two mark product density functions very simple formulae are true which contain the intensity and the pair potential function of the process. Furthermore, there is a close connection between the pair correlation function of the process and the covariance function of the random field given by the conditional intensity.
A Closed Formula for the Rule of Littlewood/Richardson with Applications in the Theory of Representations of gl(V) and the Superalgebra pl(V)
Authors: Schlosser Hartmut
Published: May 2007

A closed formula for the rule of LITTLEWOOD/RICHARDSON is given. By specialization closed formulas are gotten for the decomposition of representations of gl(V) and pl(V) resp. where V is a vector space (graduate vector space) over ℭ.
Einige Bemerkungen über die Regularität von stationären Punkten gewisser geometrischer Variationsintegrale
Authors: Duzaar Frank , Fuchs Martin
Published: May 2007

We discuss the regularity properties of weak solutions of certain degenerate elliptic systems arising from problems in geometry. For example we prove C1‐regularity of conformal m‐harmonic maps from the m‐ball into m‐dimensional oriented submanifolds of Rm+1 as well as a regularity theorem for weak H‐surfaces in Rm+1. Our arguments make strong use of a version of the isoperimetric inequality.
Mapping Properties and Composition Structure of Multidimensional Integral Transforms
Authors: Glaeske Hans‐Jürgen , Tuan Vu Kim
Published: May 2007

In this paper mapping properties of multidimensional integral transforms ℑ︁ are considered, which have a composition of the type ℑ︁ f = C ℑ︁ a ℑ︁ f, where C is a constant, ℑ︁ the Fourier transform and a denotes a function of absolute value one. Mapping properties are investigated in the spaces L2(Rn) and in Lizorkin spaces of test and generalized functions as well as in Gelfand‐Shilov spaces of test and generalized functions. Two‐ and three‐dimensional examples are discussed.
The Poincaré Method and Samojlenko Method for the Construction of Periodic Solutions to Ordinary Differential Equations
Authors: Evhuta N. A. , Zabrejko P. P.
Published: May 2007

The purpose of this paper is to propose a new approach to constructing ω‐periodic solutions to quasilinear systems of ordinary differential equations and evolution equations in BANACH spaces which embraces the classical POINCARÉ method, the numerical‐analytic SAMOJLENKO method, and other methods.
Leighton Type Oscillation Criterion and Sturm Type Comparison Theorem
Authors: Yu Y. H.
Published: May 2007

In this paper, we present a LEIGHTON type oscillation criterion and a STURM type comparison theorem. These results are obtained by using a generalized RICCATI transformation and can be applied in some cases in which classical oscillation results are not applicable.
Oscillation in Linear Differential Equations with Continuous Distribution of Time Lag
Authors: Yuanji Cheng
Published: May 2007

The purpose of this paper is to study oscillation of solutions of the following equation where Dk ϵ B(C[‐r, 0], R), k = 0, 1,…,n, r > 0, const, xt(s) = x(t + s). Under very generic conditions, we show that the oscillatory property of (1) can be determined from the behavior of the characteristic.
On the Potential Theory of the KOLMOGOROV Equation
Authors: Hoh Walter , Jacob Niels
Published: May 2007

We prove a mean value theorem for the solutions of the backward KOLMOGOROV equation. The mean values are taken over the level surfaces of the fundamental solution of the formally adjoint operator with respect to a certain measure which is identified with a measure obtained by a sweeping out procedure in the harmonic space generated by the KOLMOGOROV operator. Further we prove that the harmonic space under consideration is a strongly harmonic space and that single points are polar in this space. This makes it possible to apply a recent result of H. BAUER on the fine boundary behaviour of generalized harmonic functions.
Das kanonische Modell eines Kugelquotienten
Authors: Reimann Harry
Published: May 2007

Die Arbeit behandelt Quotienten einer komplexen Einheitskugel gerader Dimension, die sich als Zusammenhangskomponenten von SHIMURAvarietäten interpretieren lassen. Damit besitzen diese ein kanonisches Modell über einem Zahlkörper, das durch Angabe der speziellen Punkte und ihres Verhaltens unter der Wirkung von Automorphismen von C beschrieben wird.
On Products of CAUCHY Completions
Authors: Kent D. C. , de Eguino R. Ruiz
Published: May 2007

We investigate conditions under which the completion of a product of CAUCHY spaces is equivalent to the product of the completions. Necessary and sufficient conditions are given for the WYLER completion to commute with products. The natural completion and natural ordered completion are shown to commute with finite products.
Oscillation of Systems of Neutral Equations with Variable Coefficients
Authors: Georgiou D. A. , Qian C.
Published: May 2007

Consider the system of the neutral delay differential equations
(1) \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{d}{{dt}}\left[{Y\left(t \right) - R\left(T \right)Y\left({T - \varrho } \right)} \right] + P\left(t \right)Y\left({t - \tau } \right) - Q\left(t \right)Y\left({t - \sigma } \right) = 0 $\end{document}
where P(t) = (pij(t)), Q(t) = (qij(t)) and R(t) = (rij(t)) are n x n matrices for t ≧ 0 and the delays τ, σ and ϱ are nonnegative numbers. We obtain sufficient conditions for the oscillation of all solutions of (1) under the following hypotheses: magnified image
HMGA2 overexpression in non‐small cell lung cancer
Authors: Meyer Britta , Loeschke Siegfried , Schultze Anke , Weigel Thomas , Sandkamp Martin , Goldmann Torsten , Vollmer Ekkehard , Bullerdiek Jörn
Published: May 2007

Lung cancer is still the leading cause of death from cancer worldwide primarily because of the fact that most lung cancers are diagnosed at advanced stages. Overexpression of the high mobility group protein HMGA2 has been observed in a variety of malignant tumors and often correlates with poor prognosis. Herein, HMGA2 expression levels were analyzed in matching cancerous and non‐cancerous lung samples of 17 patients with adenocarcinoma (AC) and 17 patients with squamous cell carcinoma (SCC) with real‐time quantitative RT‐PCR (qRT‐PCR). Transcript levels were compared to results obtained by immunohistochemistry (IHC). HMGA2 expression was detectable by qRT‐PCR in all samples tested and varied from 5422 to 16 991 545 copies per 250 ng total RNA in the carcinoma samples and from 289 to 525 947 copies in the non‐cancerous tissue samples. In 33/34 non‐small cell lung cancer (NSCLC) samples tested, an overexpression of HMGA2 was revealed with statistically highly significant differences between non‐neoplastic and tumor samples for both AC (P < 0.0001) as well as for SCC (P < 0.0001). Expression varies strongly and is increased up to 911‐fold for AC and up to 2504‐fold for SCC, respectively, with statistically significant higher increase in SCC (P < 0.05). The results presented herein indicate that HMGA2 overexpression is a common event in NSCLC and could serve as molecular marker for lung cancer. © 2007 Wiley‐Liss, Inc.
Selective cyclooxygenase‐2 inhibition suppresses basic fibroblast growth factor expression in human esophageal adenocarcinoma
Authors: Baguma‐Nibasheka Mark , Barclay Christie , Li Audrey W. , Geldenhuys Laurette , Porter Geoffrey A. , Blay Jonathan , Casson Alan G. , Murphy Paul R.
Published: May 2007

Inhibition of cyclooxygenase (COX)‐2 is reported to suppress growth and induce apoptosis in human esophageal adenocarcinoma (EADC) cells, although the precise biologic mechanism is unclear. In this study we tested the hypothesis that the antitumor activity of COX‐2 inhibitors may involve modulation of basic fibroblast growth factor (FGF‐2), which is overexpressed in EADC. We evaluated the effects of NS‐398, a selective COX‐2 inhibitor, on FGF‐2 expression and proliferation of EADC cell lines that express COX‐2 and those that do not. We also correlated COX‐2 and FGF‐2 expression with clinico‐pathologic findings and outcome in a well‐characterized series of surgically resected EADC tissues. Seg‐1 cells robustly expressed COX‐2 and FGF‐2, whereas Bic‐1 cells expressed neither transcript. FGF‐2 was reduced to undetectable levels in Seg‐1 cells following NS‐398 treatment, but increased within 4 h of drug removal. NS‐398 significantly inhibited the growth of Seg‐1 cells, and this effect was ameliorated by addition of exogenous FGF‐2. In contrast, NS‐398 had no effect on Bic‐1 cell proliferation and FGF‐2 alone had no effect on proliferation of either cell line. NS‐398, or a neutralizing anti‐FGF‐2 antibody, induced apoptosis in Seg‐1 cells, and these effects were inhibited by addition of exogenous FGF‐2. COX‐2 protein was strongly expressed in 46% (10/22) of EADCs, and was associated with a trend towards reduced disease‐free survival. These findings indicate that the antitumor effects of COX‐2 inhibition in EADC cells may be mediated via suppression of FGF‐2, and that COX‐2 may be a clinically relevant molecular marker in the management of human EADC. © 2007 Wiley‐Liss, Inc.
Melanoma susceptibility and cell cycle genes in Xiphophorus hybrids
Authors: Butler Andrew P. , Trono David , Beard Rebecca , Fraijo Rachel , Nairn Rodney S.
Published: May 2007

Xiphophorus interspecies hybrids provide genetically defined models of both spontaneous and inducible melanomagenesis. In both models, backcrossing F1 hybrids of different strains of X. maculatus and X. helleri to a X. helleri parental fish results in segregation of melanoma susceptibility, fitting a Mendelian two‐gene inheritance model. The sex‐linked Xmrk oncogene is required for melanoma development in both crosses. The Xiphophorus CDKN2A/B gene, which is homologous to mammalian CDKN2A/B cyclin‐dependent kinase inhibitors (p16 and p15), is a candidate melanoma susceptibility gene. In this model, tumor susceptibility segregates with homozgyosity for CDKN2A/B from the recurrent X. helleri parent in backcross hybrids. We found that both CDKN2A/B mRNA and protein are highly overexpressed in melanoma. Because the p13 protein product of CDKN2A/B is a putative regulator of the G1 checkpoint, we investigated expression of other components of Xiphophorus G1 checkpoint control. By real‐time PCR analysis, retinoblastoma gene (RB) is consistently expressed twofold higher in both tumors and melanized skin than in normal tissue, indicating that RB is not downregulated by the overexpression of CDKN2A/B in Xiphophorus melanoma. We also found a significant correlation between the quantitative level of CDKN2A/B and Xmrk RNA in tumors, suggesting a functional relationship between Xmrk and CDKN2A/B expression. Although X. helleri CDKN2A/B protein contains a non‐conservative substitution, the biochemical function appears to show little overt defect. These studies indicate that in Xiphophorus melanoma, CDKN2A/B is functionally insufficient to mediate cell‐cycle arrest in the presence of Xmrk. © 2007 Wiley‐Liss, Inc.