bluuebunny/crossref_metadata_2025 huggingface dataset:
Intratesticular Androgens and Spermatogenesis During Severe Gonadotropin Suppression Induced by Male Hormonal Contraceptive Treatment
Authors: Page Stephanie T. , Kalhorn Thomas F. , Bremner William J. , Anawalt Bradley D. , Matsumoto Alvin M. , Amory John K.
Published: August 2007

ABSTRACT: Male hormonal contraceptive regimens function by suppressing gonadotropin secretion, resulting in a dramatic decrease in testicular androgen biosynthesis and spermatogenesis. Animal studies suggest that persistent intratesticular (iT)‐androgen production has a stimulatory effect on spermatogenesis in the setting of gonadotropin suppression. We hypothesized that men with incompletely suppressed spermatogenesis (>1 000 000 sperm/mL) during male hormonal contraceptive treatment would have higher iT‐androgen concentrations than men who achieved severe oligospermia (≤1 000 000 sperm/mL). Twenty healthy men ages 18–55 years enrolled in a 6‐month male contraceptive study of transdermal testosterone (T) gel (100 mg/d) plus depomedroxyprogesterone acetate (300 mg intramuscularly every 12 weeks) with or without the gonadotropin releasing hormone (GnRH) antagonist acyline (300 μg/kg subcutaneously every 2 weeks for 12 weeks) were studied. During the 24th week of treatment, subjects underwent fine needle aspirations of the testes and iT‐T and iT‐dihydrotestosterone (iT‐DHT) were measured in testicular fluid by liquid chromatography—tandem mass spectrometry. All men dramatically suppressed spermatogenesis; 15 of 20 men were severely oligospermic, and 5 of 20 suppressed to 1.5 million −3.2 million sperm per milliliter. In all subjects, mean iT‐T and iT‐DHT concentrations were 35 ± 8 and 5.1 ± 0.8 nmol/L. IT‐androgen concentrations did not significantly differ in men who did and did not achieve severe oligospermia (P = .41 for iT‐T; P = .18 for iT‐DHT). Furthermore, there was no significant correlation between iT‐T or iT‐DHT and sperm concentration after 24 weeks of treatment. In this study of prolonged gonadotropin suppression induced by male hormonal contraceptive treatment, differences in iT‐androgens did not explain differences in spermatogenesis. Additional studies to identify factors involved in persistent spermatogenesis despite gonadotropin suppression are warranted.
Effects of Long‐Term Castration on the Smooth Muscle Cell Phenotype of the Rat Ventral Prostate
Authors: Antonioli Eliane , Cardoso Alexandre Bruni , Carvalho Hernandes F.
Published: August 2007

ABSTRACT: Smooth muscle (SM) is an important component of the prostatic stroma. We previously showed that, despite extensive morphologic changes, smooth muscle cells (SMCs) of the rat ventral prostate preserve some differentiation markers 21 days after castration. In the present study, we investigated whether the expression of SMC markers is preserved in the rat ventral prostate after long‐term castration. Adult Wistar rats were castrated and sacrificed 100 days after surgery. The ventral prostates were processed for histology, stereology, immunocytochemistry (SM α‐actin and SM‐myosin heavy chain [MHC]), transmission electron microscopy (TEM), and reverse transcription polymerase chain reaction (smoothelin, sm22, and calponin). The prostates of castrated rats showed significant weight reduction, corresponding to only 5.6% of the control. Stereology showed that SMCs occupied the same proportion of the prostate volume but suffered a significant reduction in absolute volume (5.5% of control). The SMCs were retracted and showed spinous outlines. TEM revealed the presence of an abundant myofibrillar component, dense plaques, and an external lamina in these cells. SMCs were reactive to antibodies against SM α‐actin and SM‐MHC and expressed mRNA for smoothelin, sm22, and calponin. The results confirmed that rat prostatic SMCs are affected by androgen deprivation. Although showing marked phenotypic changes, these cells expressed SMC markers at the protein (SM α‐actin and SM‐MHC) and mRNA (smoothelin, sm22, and calponin) levels. These observations support the idea that SMCs may modulate their phenotypes (contractile vs synthetic) without changing their differentiation states.
Structural Alterations of Epididymal Epithelial Cells in Cathepsin A—Deficient Mice Affect the Blood‐Epididymal Barrier and Lead to Altered Sperm Motility
Authors: Hermo Louis , Korah Nadine , Gregory Mary , Liu Lauren Ye , Cyr Daniel G. , D'Azzo Alessandra , Smith Charles E.
Published: August 2007

ABSTRACT: Past studies have shown that the epithelial lining of the epididymis in adult mice deficient in protective protein cathepsin A (PPCA −/−) becomes swollen and vacuolated as a result of an accumulation of pale lysosomes, some very large, in addition to the presence of an abundance of macrophages infiltrating the intertubular spaces. The purpose of this study was to assess the integrity of the epididymal epithelial—blood barrier in these altered mice by characterizing the distribution of claudins (Cldns) and the leakiness of tight junctions to lanthanum nitrate. A second goal was to characterize sperm motility behavior in PPCA −/− mice using computer‐assisted sperm analyses (CASA). The results indicated that lanthanum nitrate penetrated apical junctional complexes between adjacent epithelial cells and entered the epididymal lumen in PPCA −/− mice but not in control PPCA +/+ mice. Immunostaining for Cldns 1, 3, 8, and 10 revealed unique patterns of expression based on cell type and region specificity in PPCA +/+ mice, which were much different in PPCA –/– mice. PPCA –/– mice showed reduced intensities of immunoreactions, complete absence of immunoreactions, and appearance of atypical cytoplasmic immunoreactions. CASA indicated that sperm counts in the PPCA –/– mice were 70% reduced, and among other problems, there was a fourfold higher percentage of static sperm in PPCA –/– mice compared with controls. These results suggest that PPCA deficiency causes structural changes to the blood‐epididymal barrier as evidenced by lanthanum nitrate and Cldns expression that affects the luminal environment of the epididymis, resulting in altered sperm motility.
Aging and Down Syndrome: Implications for Physical Therapy
Authors: Barnhart Robert C , Connolly Barbara
Published: August 2007

The number of people over the age of 60 years with lifelong developmental delays is predicted to double by 2030. Down syndrome (DS) is the most frequent chromosomal cause of developmental delays. As the life expectancy of people with DS increases, changes in body function and structure secondary to aging have the potential to lead to activity limitations and participation restrictions for this population. The purpose of this update is to: (1) provide an overview of the common body function and structure changes that occur in adults with DS as they age (thyroid dysfunction, cardiovascular disorders, obesity, musculoskeletal disorders, Alzheimer disease, depression) and (2) apply current research on exercise to the prevention of activity limitations and participation restrictions. As individuals with DS age, a shift in emphasis from disability prevention to the prevention of conditions that lead to activity and participation limitations must occur. Exercise programs appear to have potential to positively affect the overall health of adults with DS, thereby increasing the quality of life and years of healthy life for these individuals.
Higher Education Policy as Secondary School Reform: Texas Public High Schools After Hopwood
Authors: Domina Thurston
Published: August 2007

The higher education diversity programs that Texas enacted after Hopwood v. University of Texas banned affirmative action had unexpected positive consequences for the state’s high schools. The Texas top 10% law, the Longhorn Opportunity Scholarship and Century Scholarship programs, and the Towards Excellence, Access and Success Grant program each explicitly linked postsecondary opportunities to high school performance and clearly articulated that link to students across the state. As a result, these programs worked as K–16 school reforms, using college opportunities as incentives to improve educational outcomes at the high school level. Using panel data describing Texas high schools between 1993 and 2002, the author demonstrates that Texas’s post- Hopwood higher education policies redistributed college-related activity at public high schools and boosted high school students’ academic engagement.
Inquiry-Oriented Instruction in Science: Who Teaches That Way?
Authors: Smith Thomas M. , Desimone Laura M. , Zeidner Timothy L. , Dunn Alfred C. , Bhatt Monica , Rumyantseva Nataliya L.
Published: August 2007

The expansion of the No Child Left Behind Act to include science standards and assessments is likely to refocus states’ attention on science teaching and learning. Requiring teachers to have subject majors and greater funding of professional development are two key policy levers for improving instruction in science. There has been relatively little work examining the characteristics of teachers who are most likely to initiate inquiry-oriented instruction in science classrooms. Using a nationally representative sample of the teachers of eighth grade science students, the authors found relatively strong associations between reform-oriented practice and the majors and degrees that teachers earned as part of their formal schooling, as well as their current levels of participation in content-oriented professional development activities.
Does Age of Entrance Affect Community College Completion Probabilities? Evidence From a Discrete-Time Hazard Model
Authors: Calcagno Juan Carlos , Crosta Peter , Bailey Thomas , Jenkins Davis
Published: August 2007

Research has consistently shown that older students—those who enter college for the first time at age 25 or older—are less likely to complete a degree or certificate. The authors estimate a single-risk discrete-time hazard model using transcript data on a cohort of first-time community college students in Florida to compare the educational outcomes of older and traditional-age students. Contrary to conventional wisdom, the authors’ results suggest that after controlling for cognitive mathematics ability, older students enrolled in Florida community colleges have a higher conditional probability of completing a degree or certificate in the observed event period.
Cover Picture: Joining Strategies for Open Porous Metallic Foams on Iron and Nickel Base Materials (Adv. Eng. Mater. 8/2007)
Authors: Longerich S. , Piontek D. , Ohse P. , Harms A. , Dilthey U. , Angel S. , Bleck W.
Published: August 2007

The cover shows a cavity in a metal foam which developed due to large heat effects in the foam during welding. More about joining strategies of open porous metallic foams can be found in the paper by S. Angel, W. Bleck et al. on page 670.
Forming Antifouling Organic Multilayers on Porous Silicon Rugate Filters Towards In Vivo/Ex Vivo Biophotonic Devices
Authors: Kilian K. A. , Böcking T. , Ilyas S. , Gaus K. , Jessup W. , Gal M. , Gooding J. J.
Published: August 2007

We describe the development and optimization of porous silicon photonic crystal surface chemistry towards implantable optical devices. Porous silicon rugate filters were prepared to obtain a narrow linewidth reflectivity peak in the near‐infrared (700–1000 nm) with low background reflectivity elsewhere. The morphology of the mesoporous structures (pore diameter < 50 nm) was such that only small proteins could infiltrate the pores whereas larger proteins were excluded. To provide stability in biological media, we established an approach to build organic multilayers containing hexa(ethylene oxide) moieties in porous silicon. The optical changes associated with organic derivatization were monitored concurrently with FTIR characterization. Furthermore, the antifouling capability of our chemical strategy is assessed and the penetration of different sized proteins into the structure was determined. The structural stability in biological environments was evaluated by incubation in human blood plasma over time while monitoring the optical signature of the photonic crystal.
A Novel Ultra‐hydrophobic Surface: Statically Non‐wetting but Dynamically Non‐sliding
Authors: Zhao N. , Xie Q. , Kuang X. , Wang S. , Li Y. , Lu X. , Tan S. , Shen J. , Zhang X. , Zhang Y. , Xu J. , Han C. C.
Published: August 2007

In this study, we report the fabrication of a novel surface with both morphology and composition heterogeneities by casting polymer blend solution. The resultant poly (methyl methacrylate) (PMMA) and amphiphilic polyurethane (A‐PU) surface has a rough structure on microscale and separated hydrophobic and hydrophilic nanodomains as well. On this surface, water drop shows a static CA about 160° but the drop is pinned on the surface at any titled angles. This phenomenon can be ascribed to the special surface characters as the air trapped in the porous surface and hydrophobic domains repel the water, leading to a very high static CA, whereas the hydrophilic domains contacting with water at the interface, though being restrained to a little fraction by the surface roughness, adhere the drop. In addition, by adding the third component, hydrophobic fluorinated polyurethane, in the blend, the formed PMMA/A‐PU/F‐PU blend surfaces show CA about 160° but the SA be able to rationally tune from small to large by adjusting the ratio of A‐PU to F‐PU. Our method provides a novel approach for controlling surface morphology, composition and corresponding surface adhesion, and may find many applications in various fields.
Proton‐Conducting Aromatic Polymers Carrying Hypersulfonated Side Chains for Fuel Cell Applications
Authors: Lafitte B. , Jannasch P.
Published: August 2007

Polysulfone main chains have been functionalized with hypersulfonated aromatic side chains where the sulfonic acid groups were highly concentrated on a local scale, with two acid groups placed on the same aromatic ring. This molecular design was implemented to promote the nanophase separation that takes place in proton‐exchange membranes between the hydrophobic polymer main chain and the hydrophilic ionic groups responsible for the water uptake and conduction. Morphological investigations revealed that polysulfones functionalized with disulfonaphthoxybenzoyl or trisulfopyrenoxybenzoyl side chains contained larger and more uniform ionic clusters, as compared to conventionally sulfonated polysulfones where the acid groups are dispersed along the main chain. Membranes based on the polymers carrying hypersulfonated side chains formed efficient networks of water‐filled nanopores upon hydration, which facilitated excellent levels of proton conductivity exceeding that of the commercial Nafion membrane at moderate water uptakes.
Severe Henoch‐Schönlein purpura in a thalassemic patient under deferiprone treatment
Authors: Unal Sule , Güçer Safak , Kale Gülsev , Besbas Nesrin , Özen Seza , Gümrük Fatma
Published: August 2007

Herein we present a 7‐year‐old β‐thalassemia major patient who developed severe Henoch‐Schönlein purpura (HSP) with renal, pulmonary involvement and invagination while under iron chelation with deferiprone. DNA analysis for familial Mediterranean fever revealed M696V mutation. Various cellular and humoral immunological impairments have been described in thalassemia major patients and the severe course of HSP in our case may be related to these underlying immunological defects. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
Benzene production and economics: a review
Authors: Gentry Joseph C.
Published: August 2007

This paper reviews the fundamental aspects of benzene manufacturing, benzene use, and the economics of benzene production plants. The objective is to provide an essential overview of the benzene industry that will assist in improved business and technological decision‐making. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.
Design and application of a highly efficient separation technology for C9 arenes
Authors: Zhu Menglei , Sun Jinsheng , Tian YuFeng , Ren Maoming , Li Xingang
Published: August 2007

C9 arenes consist of a series of isomeric compounds with very close boiling points. Although hard to separate by distillation, e.g. the separation of 1,2,4‐trimethylbenzene and 1,3,5‐trimethylbenzene, it was possible to perform flow sheet and equipment analyses of the actual operating data by computer simulation and produce a successful flow sheet revamp. That is, with new separation technology and structured packing technology, the original flow sheet was rearranged and columns were reconstructed. The conclusion of the retrofit demonstrated increased throughput, purity and productivity of 1,2,4‐trimethylbenzene (the main product). In addition, 1,3,5‐trimethylbenzene, a very important by‐product, was obtained at higher purity. This reconstruction brings significant economic benefit and advanced technology for the separation and utilization of C9 arenes in worldwide operations. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.
Optimization of reactive distillation processes using differential evolution strategies
Authors: Babu B. V. , Khan Muzaffar
Published: August 2007

Many problems of process synthesis and design in chemical engineering can be modeled as mixed integer nonlinear programming (MINLP) problems. They include both the continuous (floating point) and integer variables. A common feature of this class of mathematical problems is the potential existence of nonconvexities due to a particular form of the objective function and/or the set of constraints. Owing to their combinatorial nature, these problems are considered to be difficult to solve. In the present study, a model based on an extension of conventional distillation is proposed for the synthesis of ethylene glycol using the nonequilibrium reactive distillation. The proposed model is simulated using the relaxation and homotopy‐continuation methods. The differential evolution (DE) algorithm is applied to find the minimum total annualized cost of the nonequilibrium reactive distillation for the synthesis of ethylene glycol, which is a MINLP optimization problem.

The optimization is performed with nonideal vapor–liquid equilibrium using ten strategies of DE, considering synthesis reaction on all trays. The results show that the optimized objective function values are better than those reported in the literature, and mostly independent of the number of trays and of the reaction distribution. It is shown that the proposed homotopy‐continuation method with DE strategy (DE/best/1/bin) is capable of providing optimized solutions which are close to the global optimum, and reveals its adequacy for the optimization of reactive distillation problems encountered in chemical engineering practice. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.
Role of green tea polyphenol crosslinking in alleviating ultraviolet‐radiation effects on collagen
Authors: Fathima Nishtar Nishad , Ansari Thamimul , Rao Jonnalagadda Raghava , Nair Balachandran Unni
Published: August 2007

The widespread application of collagen warrants studies on the effects of ultraviolet (UV) radiation on stabilized collagen. The negative impact of UV radiation is well known. Because collagen is used as a biomaterial in various biomedical applications, knowing the effects of UV irradiation on stabilized collagen has become essential. In this study, the effects of UV irradiation on collagen stabilized with green tea polyphenols, that is, Acacia mearnsii (wattle), and catechin has been studied. The fluorescence intensity has been found to decrease with irradiation for native and wattle‐treated collagen. Spectral studies have indicated that the photodegradation products increase after irradiation for native collagen, whereas collagen treated with catechin or A.mearnsii exhibits different responses depending on the duration of the irradiation. The duration of the irradiation has a significant influence on polyphenol‐treated collagen. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Morphology and mechanical property of binary and ternary polypropylene nanocomposites with nanoclay and CaCo3 particles
Authors: Chen Haibin , Wang Mozhen , Lin Yong , Chan Chi‐Ming , Wu Jingshen
Published: August 2007

Inorganic nanofillers, CaCO3 and nanoclay, are widely applied to improve the mechanical properties of polypropylene (PP). In general, the use of spherical CaCO3 can enhance the impact strength while the use of layered nanoclay can enhance the modulus and yield stress. With the objective to simultaneously improve the stiffness, strength, and impact strength of PP, in this work a ternary nanocomposite, PP/CaCO3/nanoclay (NCPP), was prepared and its morphology, crystallization, and mechanical behaviors were investigated with a comparison to the binary nanocomposites, PP/CaCO3 (CPP) and PP/nanoclay (NPP). The results showed that in NCPP the nanoclay was extremely exfoliated with a much higher degree than that in NPP, which was possibly because the incorporation of CaCO3 nanoparticles adjusted the matrix viscosity and thus provided a balance between shear stress and molecule diffusion. As a result of this highly exfoliated structure, a substantial increase in modulus and yield stress was attained in NCPP. However, its impact strength was less enhanced. The toughening effects of the CaCO3 particles observed in CPP became ineffective. This difference was ascribed to the fact that in NCPP the crystallization behavior was dominated by the nanoclay and the formation of β‐phase crystallites induced by the CaCO3 particles was inhibited. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
History of Cannabis and Its Preparations in Saga, Science, and Sobriquet
Authors: Russo Ethan B.
Published: August 2007

Cannabis sativa L. is possibly one of the oldest plants cultivated by man, but has remained a source of controversy throughout its history. Whether pariah or panacea, this most versatile botanical has provided a mirror to medicine and has pointed the way in the last two decades toward a host of medical challenges from analgesia to weight loss through the discovery of its myriad biochemical attributes and the endocannabinoid system wherein many of its components operate.

This study surveys the history of cannabis, its genetics and preparations. A review of cannabis usage in Ancient Egypt will serve as an archetype, while examining first mentions from various Old World cultures and their pertinence for contemporary scientific investigation. Cannabis historians of the past have provided promising clues to potential treatments for a wide array of currently puzzling medical syndromes including chronic pain, spasticity, cancer, seizure disorders, nausea, anorexia, and infectious disease that remain challenges for 21st century medicine. Information gleaned from the history of cannabis administration in its various forms may provide useful points of departure for research into novel delivery techniques and standardization of cannabis‐based medicines that will allow their prescription for treatment of these intractable medical conditions.
Cannabidiol – Recent Advances
Authors: Mechoulam Raphael , Peters Maximilian , Murillo‐Rodriguez Eric , Hanuš Lumír O.
Published: August 2007

The aim of this review is to present some of the recent publications on cannabidiol (CBD; 2), a major non‐psychoactive constituent of Cannabis, and to give a general overview. Special emphasis is laid on biochemical and pharmacological advances, and on novel mechanisms recently put forward, to shed light on some of the pharmacological effects that can possibly be rationalized through these mechanisms. The plethora of positive pharmacological effects observed with CBD make this compound a highly attractive therapeutic entity.
Arachidonic acid and glucose uptake by freshly isolated human adipocytes
Authors: Malipa Ana C. A. , Meintjes Roy A. , Haag Marianne
Published: August 2007

Fatty acid (FA) and glucose transport into insulin‐dependent cells are impaired in insulin resistance (IR; type 2 diabetes mellitus). Studies done on the effects of FAs on glucose uptake, and the influence of insulin on FA uptake by adipocytes, have yielded contradictory results. In this study, isolated human adipocytes were exposed to arachidonic acid (AA) and to insulin, and FA uptake as well as glucose uptake was measured. AA uptake into adipocyte membranes and nuclei was also investigated. Glucose uptake was inhibited by 57 ± 8% after 30 min of exposure to arachidonate. AA was significantly taken up into adipocyte membranes (49.6 ± 29% and 123 ± 74%) at 20 and 30 min of exposure, respectively, and into nuclei (147.6 ± 19.2%) after 30 min. Insulin stimulated AA uptake (24.1 ± 14.1%) at 30 min by adipocytes from a non‐obese subject, while inhibiting it (16.6 ± 12%) in adipocytes from an obese subject. These results suggest that: (1) AA inhibits glucose uptake by adipocytes exposed over a short period, probably by a membrane‐associated mechanism, (2) insulin‐dependent AA uptake is dependent on the body mass index (BMI) of the donor and the insulin sensitivity of their adipocytes. Copyright © 2007 John Wiley & Sons, Ltd.
Long‐chain fatty acyl‐coenzyme A‐induced inhibition of glucokinase in pancreatic islets from rats depleted in long‐chain polyunsaturated ω3 fatty acids
Authors: Zhang Ying , Bulur Nurdan , Peltier Sébastien , Carpentier Yvon A. , Malaisse Willy J. , Sener Abdullah
Published: August 2007

The metabolism of D‐glucose was recently reported to be impaired in pancreatic islets from second generation rats depleted in long‐chain polyunsaturated ω3 fatty acids. Considering the increased clearance of circulating non‐esterified fatty acids prevailing in these rats, a possible inhibition of glucokinase in insulin‐producing cells by endogenous long‐chain fatty acyl‐CoA was considered. The present study was mainly aimed at assessing the validity of the latter proposal. The activity of glucokinase in islet homogenates, as judged from the increase in D‐glucose phosphorylation rate in response to a rise in the concentration of the hexose represented, in the ω3‐depleted rats, was only 81.8 ± 4.8% (n = 11; p < 0.005) of the paired value recorded in control animals. This coincided with the fact that the inclusion of D‐glucose 6‐phosphate (3.0 mM) and D‐fructose 1‐phosphate (1.0 mM) in the assay medium resulted in a lesser fractional decrease of D‐glucose phosphorylation in ω3‐depleted rats than in control animals. Moreover, whereas palmitoyl‐CoA (50 µM) decreased the activity of glucokinase by 38.0 ± 6.0% (n = 4; p < 0.01) in islet homogenates from normal rats, the CoA ester failed to affect significantly the activity of glucokinase in islet homogenates from ω3‐depleted rats. These findings afford direct support for the view that glucokinase is indeed inhibited by endogenous long‐chain fatty acyl‐CoA in islets from ω3‐depleted rats, such an inhibition probably participating to the alteration of D‐glucose catabolism prevailing in these islets. Copyright © 2007 John Wiley & Sons, Ltd.
Locomotion of fish epidermal keratocytes on spatially selective adhesion patterns
Authors: Csucs Gabor , Quirin Katharina , Danuser Gaudenz
Published: August 2007

Cell migration results from forces generated by assembly, contraction, and adhesion of the cytoskeleton. To address how these forces integrate in space and time, novel assays are required that allow spatial separation of the different force categories. We used micro‐contact printing of fibronectin on glass substrates to study the effect of adhesion patterns on fish epidermal keratocytes locomotion. Cells migrated at similar speeds on homogeneously adhesive substrates and on patterns with 5 μm‐wide adhesive stripes interleaved by non‐adhesive stripes with a width varied between 5 and 13 μm. The leading edge protruded on adhesive stripes and lagged behind on non‐adhesive stripes. On patterns with non‐adhesive stripes wider than 13 μm cells halted, although the lamellipodium did not collapse. High correlation was found between the widths of protruding and lagging edge segments and the widths of the underlying stripes. We explain our data by the force balances between actin polymerization, contraction and adhesion on fibronectin stripes; and between actin polymerization, contraction and lamellipodium‐internal elastic tension on non‐adhesive stripes. We tested our model further by blocking lamellipodium actin network contraction and polymerization. In both experiments we observed that cells eventually lost their ability to move. However, the two perturbations induced distinct morphological responses. The data suggested that forces powering forward motion of keratocytes are largely associated with network assembly whereas contraction maintains cell polarity. This study establishes spatially selective adhesion substrates and cell morphological readouts as a means to elucidate the mechanical balance between substrate adhesion and cytoskeleton‐internal tension in cell migration. Cell Motil. Cytoskeleton, 2007. © 2007 Wiley‐Liss, Inc.
Proactive gossip‐based management of semantic overlay networks
Authors: Voulgaris Spyros , van Steen Maarten , Iwanicki Konrad
Published: August 2007

Much research on content‐based P2P searching for file‐sharing applications has focused on exploiting semantic relations between peers to facilitate searching. Current methods suggest reactive ways to manage semantic relations: they rely on the usage of the underlying search mechanism, and infer semantic relationships based on the queries placed and the corresponding replies received. In this paper we follow a different approach, proposing a proactive method to build a semantic overlay. Our method is based on an epidemic protocol that clusters peers with similar content. Peer clustering is done in a completely implicit way, that is, without requiring the user to specify preferences or to characterize the content of files being shared. In our approach, each node maintains a small list of semantically optimal peers. Our simulation studies show that such a list is highly effective when searching files. The construction of this list through gossiping is efficient and robust, even in the presence of changes in the network. Copyright © 2007 John Wiley & Sons, Ltd.
Tracking provenance in a virtual data grid
Authors: Clifford Ben , Foster Ian , Voeckler Jens‐S. , Wilde Michael , Zhao Yong
Published: August 2007

The virtual data model allows data sets to be described prior to, and separately from, their physical materialization. We have implemented this model in a Virtual Data Language (VDL) and associated supporting tools, which provide for both the storage, query, and retrieval of virtual data set descriptions, and the automated, on‐demand materialization of virtual data sets. We use a standardized data provenance challenge exercise to illustrate the powerful queries that can be performed on the data maintained by these tools, which for a single virtual data set can include three elements: the computational procedure(s) that must be executed to materialize the data set, the runtime log(s) produced by the execution of the computation(s), and optional metadata annotation(s) that associate application semantics with data and procedures. Copyright © 2007 John Wiley & Sons, Ltd.
Protein Side Chains Facilitate Mg/Al Exchange in Model Protein Binding Sites
Authors: Rezabal Elixabete , Mercero Jose M. , Lopez Xabier , Ugalde Jesus M.
Published: August 2007

Among the most frequent protein binding sites served by MgII, we identify those which have higher affinity towards AlIII. We also estimate the free energies of metal exchange for all these binding sites taking into account solvent effects explicitly. The obtained results show that thermodynamically favored MgII/AlIII exchange reactions take place at a number of these metal binding sites, which could possibly be related to some dysfunctions of MgII‐dependent biological processes. Additionally, they shed light on the molecular basis of the toxicity of AlIII in living organisms.
Evaluation of a green laser pointer for flow cytometry
Authors: Habbersett Robert C. , Naivar Mark A. , Woods Travis A. , Goddard Gregory R. , Graves Steven W.
Published: August 2007

Flow cytometers typically incorporate expensive lasers with high‐quality (TEM00) output beam structure and very stable output power, significantly increasing system cost and power requirements. Red diode lasers minimize power consumption and cost, but limit fluorophore selection. Low‐cost DPSS laser pointer modules could possibly offer increased wavelength selection but presumed emission instability has limited their use. A $160 DPSS 532 nm laser pointer module was first evaluated for noise characteristics and then used as the excitation light source in a custom‐built flow cytometer for the analysis of fluorescent calibration and alignment microspheres. Eight of ten modules tested were very quiet (RMS noise ≤ 0.6% between 0 and 5 MHz). With a quiet laser pointer module as the light source in a slow‐flow system, fluorescence measurements from alignment microspheres produced CVs of about 3.3%. Furthermore, the use of extended transit times and ≤1 mW of laser power produced both baseline resolution of all 8 peaks in a set of Rainbow microspheres, and a detection limit of <20 phycoerythrin molecules per particle. Data collected with the transit time reduced to 25 μs (in the same instrument but at 2.4 mW laser output) demonstrated a detection limit of ∼75 phycoerythrin molecules and CVs of about 2.7%. The performance, cost, size, and power consumption of the tested laser pointer module suggests that it may be suitable for use in conventional flow cytometry, particularly if it were coupled with cytometers that support extended transit times. Published 2007 Wiley‐Liss, Inc.
A new type of SRAM using DRAM technology
Authors: Kihara Yuji , Okamura Leona , Nakashima Yasushi , Izutsu Takashi , Nakamoto Masayuki , Yoshihara Tsutomu
Published: August 2007

16‐Mbit low‐power SRAM (SuperSRAM) was developed using a new memory cell technology which makes use of DRAM technology and TFT technology, which has a record of actual performance in SRAM. For SRAM, the problems of soft errors and operation at the lower limits of Vcchave manifested at the increasing levels of miniaturization, and increases in capacity have become increasingly difficult. Nonetheless, complete compatibility with asynchronous SRAM has been implemented with the free use of circuit technology, while various problems have been resolved without cost increases using DRAM memory cell technology, which reduces surface area. The characteristics of such devices are discussed predominantly from the perspective of design. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(9): 32–41, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20330
Coupling coefficient of resonators—An intuitive way of its understanding
Authors: Awai Ikuo , Zhang Yangjun
Published: August 2007

A new representation of the coupling coefficient of resonators has been obtained by the authors using the coupled mode theory. In this expression, the coupling coefficient is given by an overlap integral of the electric field and the magnetic field. This expression is extremely useful for explanation of the physical meaning of coupling. In the present paper, various microstrip resonators are discussed and their coupling mechanisms are explained by the above theory resulting in a clear interpretation that includes phenomena hitherto not adequately explained. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(9): 11– 18, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20342
Equivalent circuit analysis for vias in multilayered printed circuit boards by optimization method
Authors: Shiraki Yasuhiro , Sugahara Kengo , Murata Yuichiro , Nishi Shinya
Published: August 2007

In this paper, a highly accurate equivalent circuit is constructed that can calculate the transmission characteristics of the vias connecting the layers in multilayered printed circuit boards. Various factors of the vias affecting the transmission characteristics are discussed. The present equivalent circuit is based on the physical structure and the equivalent circuit parameters are determined by an optimization method. The equivalent circuit is applied to the vias in printed circuit boards with more than 10 layers. The results of evaluation of the transmission characteristics in the gigahertz range are verified by the FDTD method and by measurement so as to verify their validity. Further, by using the present equivalent circuit, the effects of various factors of the vias on the transmission characteristics are studied. It is demonstrated that the time needed for study by the equivalent circuit is less than that needed for numerical analysis. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(9): 1–10, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20350
Realization of feature description systems for clusters by rule generation based on genetic programming and its applications
Authors: Lu Jianjun , Kishikawa Yoshinori , Tokinaga Shozo
Published: August 2007

This paper deals with the realization of feature description systems for clusters by rule generation based on genetic programming (GP) and its applications. First, the data are divided into several clusters by using conventional clustering algorithms. Then logical variables corresponding to the categorical variables are introduced, and the logical expressions using these logical variables are defined as rules to extract the targeted cluster from the dataset. The rules are improved by GP so that they are valid (become true) only for the targeted cluster. Unlike ordinary GP procedures, the fitness of individuals is defined as proportional to the number of hits inside the targeted cluster, but also to the inverse of the number of hits outside the targeted cluster. In simulation studies, the system is applied first to artificially generated samples and clusters to examine the performance of the system, and then to personal loan assessment problems, after which the evaluation of several kinds of clustering problems is summarized. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(9): 87– 97, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20380
Interoperability of mobile agents for ubiquitous applications
Authors: Hasegawa Tetsuo , Cho Kenta , Ohsuga Akihiko , Kumeno Fumihiro , Nakajima Shin , Honiden Shinichi
Published: August 2007

A mobile agent is an important platform for applications for the coming ubiquitous society. Many different kinds of mobile agent platforms have been developed. However, agents from one agent platform are generally not able to migrate into another agent platform. As a solution to this problem, we propose an interoperability concept using an incarnation agent. The concept realizes logical mobility within different kinds of agent platforms. The incarnation agent extracts an agent's procedures and status, compiling them into agent platform independent format and then re‐compiling them to target agent platform format, thus enabling the process to continue. The incarnation agent also has autonomy for interoperability. It manages complex migration for interoperability, so agent's procedure can be described in simple mobile model. Moreover, the incarnation agent modifies agent's procedures as applicable to facilities of target agent platform. This paper also reports an interoperability middle‐ware and its examination. The middle‐ware is a foundation of realizing the Incarnation Agent, and the response time and network traffic overheads by the interoperability middle‐ware has been measured. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(4): 49–59, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20388
A study on bid strategies for electric power suppliers in bilateral market considering spot market
Authors: Hayashi Tokuhisa , Kita Hiroyuki , Tanaka Eiichi , Hasegawa Jun
Published: August 2007

As deregulation in the electric power industry has advanced in many countries, a spot market and a futures market for electric energy have already been formulated. In Japan, the foundation of a day‐ahead spot market is scheduled for the 2005 fiscal year. This paper presents a method to evaluate the expected profit and risk for an electric power supplier considering both spot market and bilateral market. In this paper, the Vasicek model is used to represent the fluctuations in spot price and demand in a bilateral market, and additionally, Value at Risk (VaR) is used as a risk index. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(4): 1–11, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20515
Mesoporous Carbon Prepared from Carbohydrate as Hard Template for Hierarchical Zeolites (Eur. J. Inorg. Chem. 25/2007)
Authors: Zhu Kake , Egeblad Kresten , Christensen Claus Hviid
Published: August 2007

The cover picture shows a novel method for producing mesoporous zeolite single crystals by using cheap and easily prepared porous carbon as the mesopore template. The porous carbon template was obtained by carbonization in Ar of a hydrothermally treated sucrose/ammonia mixture, and it was successfully applied as an inert carbon matrix during zeolite crystallization. After hydrothermal crystallization, combustion of the carbon embedded in the zeolite crystals yielded mesoporous zeolite single crystals. Details are discussed in the article by C. H. Christensen et al. on p. 3955 f.
meso,meso‐Linked and Triply Fused Diporphyrins with Mixed‐Metal Ions: Synthesis and Electrochemical Investigations
Authors: Fendt Leslie‐Anne , Fang Hongjuan , Plonska‐Brzezinska Marta E. , Zhang Sheng , Cheng Fuyong , Braun Christophe , Echegoyen Luis , Diederich François
Published: August 2007

A novel series of biaryl‐type, meso,meso‐linked and planar, triply fused diporphyrin derivatives was prepared and fully characterized together with the corresponding monoporphyrin control compounds. They feature peripheral meso‐3‐cyanophenyl and meso‐3,5‐cyanophenyl groups, which have previously been shown to undergo transformation into malonates without perturbation of the porphyrin core and subsequent Bingel addition to fullerene C60. The tetrapyrrolic metal binding sites in the diporphyrin arrays are either complexed to two ZnII or CuII ions, or, in a mixed coordination, to one CuII and one ZnII ion; alternatively, one or both sites remain unoccupied. The interaction between the differentially metallated porphyrin rings was systematically investigated by UV/Vis spectroscopy and electrochemistry. Cyclic voltammetry and differential pulse voltammetry reveal that electronic communication in the diporphyrin arrays varies strongly with the mode of connection (meso,meso‐linked or triply fused), the nature of the bound metal ion, and the number of peripheral cyano groups. The electrochemical HOMO–LUMO gap in both series of diporphyrins is strongly but differentially affected by the choice of the inserted metal ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Econometric modelling for short‐term inflation forecasting in the euro area
Authors: Espasa Antoni , Albacete Rebeca
Published: August 2007

This paper examines the problem of forecasting macro‐variables which are observed monthly (or quarterly) and result from geographical and sectorial aggregation. The aim is to formulate a methodology whereby all relevant information gathered in this context could provide more accurate forecasts, be frequently updated, and include a disaggregated explanation as useful information for decision‐making. The appropriate treatment of the resulting disaggregated data set requires vector modelling, which captures the long‐run restrictions between the different time series and the short‐term correlations existing between their stationary transformations. Frequently, due to a lack of degrees of freedom, the vector model must be restricted to a block‐diagonal vector model. This methodology is applied in this paper to inflation in the euro area, and shows that disaggregated models with cointegration restrictions improve accuracy in forecasting aggregate macro‐variables. Copyright © 2007 John Wiley & Sons, Ltd.
Can panel data really improve the predictability of the monetary exchange rate model?
Authors: Westerlund Joakim , Basher Syed A.
Published: August 2007

A common explanation for the inability of the monetary model to beat the random walk in forecasting future exchange rates is that conventional time series tests may have low power, and that panel data should generate more powerful tests. This paper provides an extensive evaluation of this power argument to the use of panel data in the forecasting context. In particular, by using simulations it is shown that although pooling of the individual prediction tests can lead to substantial power gains, pooling only the parameters of the forecasting equation, as has been suggested in the previous literature, does not seem to generate more powerful tests. The simulation results are illustrated through an empirical application. Copyright © 2007 John Wiley & Sons, Ltd.
Is there a relationship between elderly suicide rates and smoking? A cross‐national study
Authors: Shah Ajit
Published: August 2007

Background

An independent relationship between smoking cigarettes and completed suicides has been reported in several cohort and case‐control studies of younger subjects, but this relationship has rarely been examined in the elderly.

Methods

The relationship between the prevalence of smoking in males and females and suicide rates in males and females in the age‐bands 65–74 years and 75 + years was examined using national‐level aggregate data from the World Health Organisation and the United Nations Development Programme websites. In addition to univariate analysis, multivariate analysis were conducted to ascertain an independent relationship between the prevalence of smoking and elderly suicide rates.

Results

The main findings were: (i) on univariate analysis, the prevalence of smoking in males was positively correlated with suicide rates in males aged 65–74 years and males aged 75 + years, but this relationship was absent in females and (ii) on multivariate analysis there was no independent relationship between the prevalence of smoking in males and suicide rates in males in both the elderly age‐bands.

Conclusions

There is a case for examination of the relationship between smoking and elderly suicides in individual‐level cohort or case‐control studies because of the potential methodological difficulties in cross‐national studies using national‐ level aggregate data, paucity of cohort or case‐control studies at an individual‐level in the elderly, and the observation of an independent relationship between smoking and completed suicides in individual‐level cohort and case‐control studies in younger age groups. Copyright © 2007 John Wiley & Sons, Ltd.