bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of thin-walled frames considering joint flexibilities
Authors: Marur P R
Published: October 2007

TAnalytical models are developed for static and dynamic analysis of thin-walled frames representing the automotive side structures. The model is based on one-dimensional beam theory that considers joint flexibility to compute stiffness and frequency response of the whole frame structure. The computed out-of-plane displacements under static and impact loading are in good agreement with those obtained from the shell finite element method. Using the validated analytical model, the influence of joint flexibility on the elastic response of the side structure is studied.
The deformity index as a predictor of final radiological outcome in Perthes’ disease
Authors: Nelson D. , Zenios M. , Ward K. , Ramachandran M. , Little D. G.
Published: October 2007

The deformity index is a new radiological measurement of the degree of deformity of the femoral head in unilateral Perthes’ disease. Its values represent a continuous outcome measure of deformity incorporating changes in femoral epiphyseal height and width compared with the unaffected side. The sphericity of the femoral head in 30 radiographs (ten normal and 20 from patients with Perthes’ disease) were rated blindly as normal, mild, moderate or severe by three observers. Further blinded measurements of the deformity index were made on two further occasions with intervals of one month.

There was good agreement between the deformity index score and the subjective grading of deformity. Intra- and interobserver agreement for the deformity index was high. The intraobserver intraclass correlation coefficient for each observer was 0.98, 0.99 and 0.97, respectively, while the interobserver intraclass correlation coefficient was 0.98 for the first and 0.97 for the second set of calculations.

We also reviewed retrospectively 96 radiographs of children with Perthes’ disease, who were part of a multicentre trial which followed them to skeletal maturity. We found that the deformity index at two years correlated well with the Stulberg grading at skeletal maturity. A deformity index value above 0.3 was associated with the development of an aspherical femoral head. Using a deformity index value of 0.3 to divide groups for risk gives a sensitivity of 80% and specificity of 81% for predicting a Stulberg grade of III or IV.

We conclude that the deformity index at two years is a valid and reliable radiological outcome measure in unilateral Perthes’ disease.
Aneurysmal bone cysts of the distal fibula in children
Authors: Lampasi M. , Magnani M. , Donzelli O.
Published: October 2007

We report the results of the treatment of nine children with an aneurysmal bone cyst of the distal fibula (seven cysts were juxtaphyseal, and two metaphyseal). The mean age of the children was 10 years and 3 months (7 years and 4 months to 12 years and 9 months). All had open physes. All cysts were active and in seven cases substituted and expanded the entire width of the bone (type-2 lesions). The mean longitudinal extension was 5.7 cm (3 to 10). The presenting symptoms were pain, swelling and pathological fracture. Moderate fibular shortening was evident in one patient.

In six patients curettage was performed, using phenol as adjuvant in three. Three with juxtaphyseal lesions underwent resection. A graft from the contralateral fibula (one case) and allografts (two cases) were positioned at the edge of the physis for reconstruction. The mean follow-up was 11.6 years (3.1 to 27.5). There was no recurrence.

At the final follow-up there was no significant difference in the American Orthopaedic Foot and Ankle Society scores (excellent/good in all cases) and in growth disturbance, alignment, stability and bone reconstitution, but in the resection group the number of operations, including removal of hardware, complications (two minor) and time of immobilisation/orthosis, were increased. Movement of the ankle was restricted in one patient.

The potential risks in the management of these lesions include recurrence, physeal injury, instability of the ankle and hardware and graft complications. Although resection is effective it should be reserved for aggressive or recurrent juxtaphyseal lesions.
Are occult fractures of the hip and pelvic ring mutually exclusive?
Authors: Lakshmanan P. , Sharma A. , Lyons K. , Peehal J. P.
Published: October 2007

We have evaluated retrospectively the relationship of bony injuries seen on 106 consecutive MR scans in elderly patients of a mean age of 81.4 years (67 to 101) who were unable to bear weight after a low-energy injury.

There were no visible fractures on plain radiographs of the hip but eight patients (7.5%) had fractures of the pubic ramus. In 43 patients (40.5%) MRI revealed a fracture of the femoral neck and in 26 (24.5%) there was a fracture of a pubic ramus. In 17 patients (16%) MRI showed an occult sacral fracture and all of these had a fracture of the pubic ramus. No patient with a fracture of the femoral neck had an associated fracture of the pelvic ring or vice versa. Occult fracture of the hip and of the pelvic ring appear to be mutually exclusive and if an acute fracture of the pubic ramus is diagnosed radiologically further investigations are not needed to rule out an occult fracture of the hip.
Osteoarthritis of the costovertebral joints
Authors: Sales J. R. , Beals R. K. , Hart R. A.
Published: October 2007

Thoracic back pain caused by osteoarthritis of a single costovertebral joint is a poorly recognised condition. We report a series of five patients who were successfully treated by resection arthroplasty of this joint.

Each had received a preliminary image-guided injection of local anaesthetic and steroid into the joint to confirm it as the source of pain. The surgical technique is described. There were no complications. The pain improved from a mean of 7.0 (6 to 8) on a visual analogue scale to 2.0 (0 to 4) post-operatively. The final post-operative Oswestry disability index was a mean of 19.4 (9 to 38).

Isolated osteoarthritis of a costovertebral joint is a rare but treatable cause of thoracic back pain. It is possible to obtain excellent short- and intermediate-term relief from pain with resection arthroplasty in appropriately selected patients.
Biphasic Effect of Prostaglandin E2 on Osteoclast Formation in Spleen Cell Cultures: Role of the EP2 Receptor
Authors: Ono Katsuhiro , Kaneko Hironori , Choudhary Shilpa , Pilbeam Carol C , Lorenzo Joseph A , Akatsu Takuhiko , Kugai Nobuo , Raisz Lawrence G
Published: October 2007

We examined the effect of PGE2 on OC formation from spleen cells treated with M-CSF and RANKL. PGE2 decreased OC number at 5–6 days of culture and increased OC number, size, and resorptive activity at 7–8 days. A selective EP2 receptor agonist mimicked these effects. Deletion of the EP2 receptor or depletion of T-cells abrogated the increase in OC number.

Introduction: Prostaglandin E2 (PGE2) has been reported to increase osteoclast (OC) number in spleen cells cultured with RANKL and macrophage-colony-stimulating factor (M-CSF). In this study, we examined the time course of PGE2 effects on spleen cells cultured with RANKL and M-CSF. We then investigated which PGE receptors and cell types were involved in these effects.

Materials and Methods: Spleen cells were cultured from wildtype C57BL/6 mice and EP2 or EP4 receptor-deficient (−/−) and wildtype (+/+) mice on a mixed genetic background. Spleen cells were cultured with M-CSF and RANKL for 5–9 days with or without PGE2 or selective agonists for the four PGE2 receptors (EP1A, EP2A, EP3A, or EP4A). Some cultures were performed using T-cell-depleted spleen cells. OC number and size were quantitated. OC apoptosis and pit formation were measured at 7 or 8 days.

Results: PGE2 decreased the number of OCs formed in the presence of RANKL and M-CSF at 5–6 days of culture and increased OC number at 8–9 days compared with cultures without PGE2. PGE2 also increased OC size at 7 and 8 days, decreased apoptosis of OC at 7 days, and increased pit formation at 8 days. EP1A or EP4A had no effect on OC. EP3A decreased OC number. EP2A mimicked effect of PGE2. EP2−/− spleen cells showed no increase in OC number in response to PGE2, whereas deletion of EP4 had no effect. Depletion of T-cells abrogated the late increase of OC number.

Conclusions: We conclude that PGE2 has an initial inhibitory effect on OC formation in spleen cell cultures, possibly mediated by both EP2 and EP3 receptors, and a later stimulatory effect, mediated by the EP2 receptor, possibly acting on T-cells.
Understanding Low-Sloped Roofs Under Hurricane Charley From Field to Practice
Authors: Baskaran A. , Molleti S. , Roodvoets D.
Published: October 2007

Natural wind hazard damages have been dramatic in recent years, incurring losses of life and property around the world. Wind-induced failure is one of the major contributors to insurance claims, and it is rising. To address these growing concerns, RICOWI (Roofing Industry Committee on Weather Issues) started a Wind Investigation Program (WIP) to investigate the field performance of roofing assemblies after major windstorm events and to factually describe roof assembly performance and modes of damage. As part of this program, Hurricane Charley, which hit Punta Gorda, FL, with winds exceeding 140 mph (63 m/s), was investigated. This paper mainly focuses on the field performance of the low-sloped roofs with three important parameters that were found critical in the failure of the roofing systems, namely, • Effect of corner wind suction, • Effect of parapet, • Effect of internal pressure. For each scenario, first scientific documentation was presented, and then how the field observation reflects the fundamental principles were discussed. Based on this exercise, correlations are developed for roof wind design. In addition, wind design data from the North American codes of practice are also calculated and compared to show the impact of science and field observation on durable roof design. With these illustrations, this paper offers recommendations to advance the roof system design for hurricane-prone regions.
Política social na periferia do capitalismo: a situação recente no Brasil
Authors: Pochmann Marcio
Published: October 2007

Por ser um país situado na periferia do capitalismo mundial, uma vez que não dispõe de moeda de curso internacional e apresenta-se com débil capacidade de produção e difusão tecnológica, o Brasil desenvolve, com muita especificidade, a sua política social. Em grande medida, as últimas duas décadas, por força da Constituição de 1988, foram de reconhecidos avanços na política social, apesar dos constrangimentos considerados no comportamento mais geral da economia frente ao seu baixo dinamismo e as conseqüências do aumento do desemprego e da precarização dos postos de trabalho. Simultaneamente, a condição de semi-estagnação da renda per capita dos brasileiros tem sido acompanhada de medidas de constantes ajustes fiscais, que constrangem a evolução mais recente do gasto social. Tudo esse esforço fiscal termina, muitas vezes, sustentando o ciclo da financeirização de riqueza, especialmente para a diminuta parcela da sociedade que se coloca na condição de detentores dos títulos da dívida pública. A análise dessa especificidade nacional pode permitir compreender a perda atual da oportunidade de superação de grande parte das mazelas sociais do país. Isso porque a política social possui uma importante ação sobre a população de menor renda.
Direito à saúde, atenção básica e transferências condicionadas de renda na América Latina
Authors: Fonseca Ana Maria Medeiros da , Viana Ana Luiza d'Ávila
Published: October 2007

Os programas de transferência de renda na América Latina foram acompanhados de condicionalidades - responsabilidades com o objetivo de melhorar os níveis educacionais, impedir a evasão escolar e o trabalho infantil e também para melhorar os indicadores de saúde e nutrição. Apesar da relativa uniformidade encontrada na condicionalidade vinculada à saúde, as estratégias utilizadas pelos governos para cumprir com as metas e os objetivos estabelecidos são diversas e configuram dificuldades adicionais para a melhoria das condições de vida das populações mais vulneráveis. Longe de essa iniciativa incentivar o direito à saúde, talvez o que promova seja expansão de um novo ciclo de programas de atenção básica focalizados e de natureza provisória.
Transformações e continuidades nos programas de bem-estar social no Canadá
Authors: Lessa Iara
Published: October 2007

As mães pobres e suas famílias constituem um dilema central a um sistema de bem-estar social que visa principalmente encorajar e manter os trabalhadores na força de trabalho. As transferências de renda pelo poder público para este e outros grupos marginalizados podem ser vistas como um desestímulo ao trabalho assalariado e têm sido, desde o início do século XX no Canadá, marcadas por enormes mesquinhez e contradições. Esse artigo discute transformações recentes nesses programas e seus efeitos nas famílias e indivíduos, enfocando o caso específico das mulheres pobres mantendo suas famílias sozinhas. Ele argumenta que o corte e re-definição gradual dos programas mudaram a natureza do estado de bem-estar social no Canadá e reduzem os caminhos para sair da pobreza disponíveis a grupos marginalizados.
Crenças e influências sobre dietas de emagrecimento entre obesos de baixa renda
Authors: Cavalcanti Ana Paula Rodrigues , Dias Mardonio Rique , Rodrigues Carla Fernanda Ferreira , Gouveia Charlene Nayana Nunes Alves , Ramos Deborah Dornellas , Serrano Fagner José de Oliveira
Published: October 2007

A obesidade tornou-se uma epidemia carente de controle imediato, principalmente entre pobres, mulheres e pessoas de baixa escolaridade. A OMS solicita e vários estudos corroboram que estudos esclarecedores sobre os comportamentos psicológicos e sociais interferentes na aderência terapêutica aos regimes devem ser encorajados. Este estudo usou a Teoria da Ação Racional - TAR, de M. Fishbein, em Psicologia Social, e comparou duas séries de entrevistas abertas (em 2001 e 2005) que eliciaram as crenças positivas (vantagens) e negativas (desvantagens) sobre fazer dieta entre obesos de baixa renda de João Pessoa, Paraíba, além dos referentes (pessoas de opinião influente) destes pacientes quanto a segui-la. Os resultados de 2001 foram corroborados em 2005, revelando o medo das doenças relacionadas à obesidade e a vontade de sentir mais saúde e leveza de corpo. Mães, filhos e principalmente o cônjuge aparecem como apoiadores do regime. Ressaltou-se que não bastaria força de vontade, mas também reflexão e construção de habilidades de controle, apropriação e modificação das condições de vida. Preocupações estéticas não foram prioritárias. Estas informações podem fomentar melhores resultados na aderência terapêutica.
Consentimento livre e esclarecido em odontologia nos hospitais públicos do Distrito Federal
Authors: Maluf Fabiano , Carvalho Gilberto Paiva de , Diniz Júnior José Caubi , Bugarin Junior João Geraldo , Garrafa Volnei
Published: October 2007

A individualidade e o poder de decisão dos indivíduos devem ser respeitados. A autonomia manifestada por meio do consentimento livre e esclarecido é a fonte de tal respeito. Este trabalho visou levantar dados sobre a realidade no uso do consentimento livre e esclarecido nos hospitais públicos do Distrito Federal. Um questionário foi encaminhado aos dentistas dos hospitais públicos para ser respondido. Os resultados obtidos demonstram que, no início do tratamento, é utilizado o consentimento livre e esclarecido, de forma verbal, na maioria dos hospitais. Observam-se, ainda, equívocos na utilização e conceituação do consentimento livre e esclarecido. Os documentos misturam autorização do uso de imagem, com consentimento livre e esclarecido. Os documentos apresentam poucas informações e não esclarecem aspectos importantes do tratamento. Portanto, os cirurgiões-dentistas atuantes na rede pública hospitalar necessitam de um aprofundamento nos fundamentos bioéticos com o intuito de congregarem, ao princípio da beneficência, já consolidado e normatizado, o princípio da autonomia.
Characterizing crosstalk in anaglyphic stereoscopic images on LCD monitors and plasma displays
Authors: Woods Andrew J. , Yuen Ka Lun , Karvinen Kai S.
Published: October 2007

Abstract— In 1853, William Rollman developed the inexpensive and easy to use anaglyph method for displaying stereoscopic images. Although it can be used with nearly any type of full‐color display, the anaglyph method compromises the accuracy of color reproduction, and it often suffers from crosstalk (or ghosting) between the left‐ and right‐eye image channels. Crosstalk degrades the ability of the observer to fuse the stereoscopic image, and hence reduces the quality of the 3‐D image. Crosstalk is present in various levels with most stereoscopic displays; however, it is often particularly evident with anaglyphic 3‐D images. This paper summarizes the results of two projects that characterized the presence of anaglyphic crosstalk due to spectral issues on 13 LCD monitors, 14 plasma displays, and a CRT monitor when used with 25 different pairs of anaglyph 3‐D glasses. A mathematical model was used to predict the amount of crosstalk in anaglyphic 3‐D images when different combinations of displays and glasses are used, and therefore highlight displays, glasses, and combinations thereof which exhibit lower levels of crosstalk when displaying anaglyphic 3‐D images.
Experimental Study of Phase-Transformation Effects on Relative Permeabilities in Fractures
Authors: Chen Chih-Ying , Li Kewen , Horne Roland N.
Published: October 2007

Phase transformation affects multiphase flow in geothermal and gas/condensate reservoirs owing to the same substance occurring in different phases. These effects change the phase behavior and the flow characteristics. The goals of this research were to compare the flow behavior and relative permeability differences between two-phase flow with and without phase-transformation effects in smooth-walled and rough-walled fractures. During this research, an experimental apparatus was built to capture the unstable nature of the two-phase flow in fractures and to display the flow structures in real time. Two-phase-flow experiments with phase-transformation effects (steam/water flow) and without phase-transformation effects (nitrogen/water flow) were conducted. The porous-medium approach was used to calculate two-phase relative permeabilities. From the results in this study, steam/water relative permeabilities are different from nitrogen/water relative permeabilities. The enhanced steam-phase relative permeability is caused by the effects of phase transformation. This shows consistency with some earlier studies in porous media. The nitrogen/water relative permeability is described most appropriately by using the viscous coupling model. However, steam/water flow in the rough-walled fracture, which is coupled with strong phase-transformation effects, seems to be represented better by Brooks-Corey relative permeability functions for fractured media (λ→∞). The results from this study suggest that relative permeabilities accounting for phase-transformation effects must be used in simulations of geothermal and solution-gas reservoirs to represent two-phase interactions adequately.
Simulation of Miscible Flow Including Bypassed Oil and Dispersion Control
Authors: Coats K. H. , Thomas L. K. , Pierson R. G.
Published: October 2007

This paper describes methods for the simulation of first-contact miscible (FCM), multicontact miscible, and vaporizing gas drive, which include logic to account for bypassed oil. Dispersion control is included for FCM cases.

First-contact miscibility may be simulated in fully compositional mode with any number of components, Nc, or in two-pseudocomponent equation-of-state (EOS) mode. Pseudoization is performed internally in the model so that hydrocarbon-fluid density and viscosity, as functions of pressure and composition, are the same as calculated in Nc-component mode. Bypassed oil and dispersion control are based on an extension of Koval's (1963) method. This procedure allows the user to adjust the fractional flow of oil during upscaling or history matching to match fine-grid or historical results. This feature can be used to simulate both water-alternating-gas (WAG) and tertiary-recovery projects where solvent injection is preceded by a water-injection period.

Example cases are included to illustrate the techniques presented in this paper. Results are also given on the efficiencies of the algorithms.
Fluid Characterization for Miscible EOR Projects and CO2 Sequestration
Authors: Jessen Kristian , Stenby Erling H.
Published: October 2007

Accurate performance prediction of miscible enhanced-oil-recovery (EOR) projects or CO2 sequestration in depleted oil and gas reservoirs relies in part on the ability of an equation-of-state (EOS) model to adequately represent the properties of a wide range of mixtures of the resident fluid and the injected fluid(s). The mixtures that form when gas displaces oil in a porous medium will, in many cases, differ significantly from compositions created in swelling tests and other standard pressure/volume/temperature (PVT) experiments. Multicontact experiments (e.g., slimtube displacements) are often used to condition an EOS model before application in performance evaluation of miscible displacements. However, no clear understanding exists of the impact on the resultant accuracy of the selected characterization procedure when the fluid description is subsequently included in reservoir simulation.

In this paper, we present a detailed analysis of the quality of two different characterization procedures over a broad range of reservoir fluids (13 samples) for which experimental swelling-test and slimtube-displacement data are available. We explore the impact of including swelling-test and slimtube experiments in the data reduction and demonstrate that for some gas/oil systems, swelling tests do not contribute to a more accurate prediction of multicontact miscibility. Finally, we report on the impact that use of EOS models based on different characterization procedures can have on recovery predictions from dynamic 1D displacement calculations.
Liver cystic echinococcosis in humans — a study of 30 cases
Authors: Ćulafić D. , Katić-Radivojević S. , Kerkez M. , Vukčević M. , Ranković V. , Stefanović D.
Published: October 2007

The aim of this study is to demonstrate the clinical manifestations and diagnostic approach to liver hydatid disease and suggest its treatment. The prospective study was carried out on 30 patients with liver hydatidosis. Hepatologic examinations were based on: medical history, physical examination, biochemical and serological tests, ultrasonography and computed tomography scanning. Twenty-five (83.3 %) patients underwent radical cyst resection, while in 5 (16.7 %) cases liver resection with left lobectomy was also performed. Hydatid cyst was histopathologically verified in all the patients. Our results showed that the patients with multiple cysts had impaired functional liver tests significantly more often than patients with unilocular cyst. In addition, ultrasonography and computed tomography scans are the valid imaging procedures in diagnosis. Radical, surgical resection of hepatic hydatid cysts is the goal of treatment.
Gastrointestinal helminths found in the three freshwater turtles (Erymnochelys madagascariensis, Pelomedusa subrufa and Pelusios castanoides) from Ankarafantsika National Park, Madagascar
Authors: Roca V. , García G. , Montesinos A.
Published: October 2007

We conducted a survey of the presence, prevalence and diversity of gastrointestinal helminths in faecal samples and stomach contents of three turtle species, — Erymnochelys madagascariensis (Chelonia: Podocnemididae), Pelomedusa subrufa and Pelusios castanoides (Chelonia: Pelomedusidae), — from several localities in Madagascar. Four nematode species were detected: Atractis chabaudi, Camallanus chelonius, Falcaustra pelusios, and Spiroxys sp. E. madagascariensis, with all four species, had the greatest helminth diversity. A. chabaudi was the community’s core species, whereas Spiroxys sp. was a satellite species. Only two species (A. chabaudi and Spiroxys sp.) were found in P. subrufa and only one, Spiroxys sp., in P. castanoides. These are the first helminthological data on E. madagascariensis, one of the most threatened freshwater turtles in the world.
Morphometrics of females, juveniles and a hermaphrodite of Longidorus distinctus Lamberti et al., 1983 (Nematoda: Longidoridae) from Slovakia
Authors: Lišková M.
Published: October 2007

A population of Longidorus distinctus Lamberti, Choleva & Agostinelli, 1983 was recovered from soil samples collected from the rhizosphere of plum trees at Král’ovský Chlmec in south-eastern Slovakia. The area is characterized by sandy soil derived from dune sand. The population comprised females, juveniles of four developmental stages and a bisexual specimen. No males were found. It is the first record of this species from Slovakia. Two females were sequenced and the sequence was deposited in Gen-Bank.
Parasites of carp bream, Abramis brama, from Lake Jamno, Poland
Authors: Dzika E. , Kuształa A. , Kuształa M.
Published: October 2007

A total of 40 carp bream, Abramis brama (L.) from Lake Jamno were examined for their parasites in May 2002. Lake Jamno is a brackish-water coastal lagoon, strongly eutrophied and polluted by communal and industrial sewage from the city of Koszalin. The survey yielded 15 parasite species, representing different systematic groups, including 7 monogeneans Dactylogyrus auriculatus, D. falcatus, D. wunderi, D. zandti, Gyrodactylus elegans, Gyrodactylus sp., Diplozoon paradoxum; 4 digeneans (at the stage of metacercaria) Diplostomum sp., Tylodelphys clavata, Ichthyocotylurus platycephalus, I. variegatus; 1 cestode Caryophyllaeus laticeps; 2 crustaceans Ergasilus sieboldi, Argulus foliaceus; and 1 hirudinean Caspiobdella fadejewi. Monogeneans constituted the most abundant parasite group, accounting for 61.5 % of all parasite individuals collected. They were followed by the cestodes (20.7 %), digenean flukes (16 %), crustaceans (0.7 %), and leeches (0.2 %).
First report of an entomopathogenic nematode from continental Portugal
Authors: Valadas V. , Boyle S. , Vieira P. , Kakouli-Duarte T. , Mota M.
Published: October 2007

In continental Portugal no information is available concerning the occurrence of entomopathogenic nematodes. During a survey in several different habitats from the southern regions of the country, several isolates where identified as Steinernema feltiae. This represents the first report of an entomopathogenic nematode genus for continental Portugal.
On existence of tame Harrison map
Authors: Koprowski Przemysław
Published: October 2007

We present here two new criteria for existence of a tame Harrison map of two formally real algebraic function fields over a fixed real closed field of constants. The first criterion (c.f. Theorem 2.5) shows that a square class group isomorphism is a tame Harrison map if it induces an isomorphism of the coproduct rings of residue Witt rings. The other result (c.f. Proposition 3.5) associates a tame Harrison map to an integral quaternion-symbol equivalence.
Oscillation of nonlinear second order matrix differential equations
Authors: Parhi N. , Praharaj P.
Published: October 2007

In this paper, sufficient conditions are obtained for oscillation of all nontrivial, prepared, symmetric solutions of a class of nonlinear second order matrix differential equations of the form
$$(P(t)Y')' + Q(t)F(Y) = 0, t \geqslant 0,$$
and
$$Y'' + Q(t)F(Y) = 0, t \geqslant 0.$$
On some new type generalized difference sequence spaces
Authors: Esi Ayhan , Tripathy Binod , Sarma Bipul
Published: October 2007

In this paper we introduce a new type of difference operator Δmn for fixed m, n ∈ ℕ. We define the sequence spaces ℓ∞(Δmn), c(Δmn) and c
0(Δmn) and study some topological properties of these spaces. We obtain some inclusion relations involving these sequence spaces. These notions generalize many earlier existing notions on difference sequence spaces.
The design of the century
Authors: Forbes A. , Grannell M. , Griggs T.
Published: October 2007

We construct a 2-chromatic Steiner system S(2, 4, 100) in which every block contains three points of one colour and one point of the other colour. The existence of such a design has been open for over 25 years.
3D Microstructured Surfaces Obtained by Soft‐Lithography Using Fast‐Crosslinking Elastomeric Precursors and 2D Masters
Authors: del Campo A. , Álvarez I. , Filipe S. , Wilhelm M.
Published: October 2007

A new method for the fabrication of microstructured polymer surfaces possessing features with different 3D geometries is reported. Controlled micromolding using masters with 2D topographies and fluid elastomeric precursors with various viscosities and crosslinking kinetics yielded homogeneously structured surfaces possessing microtubes and concave and convex hemispheres with defined dimensions. This fabrication strategy does not require sophisticated 3D structuring equipment and can be extended to other materials, dimensions and geometries.
Organic Light Emitting Field Effect Transistors: Advances and Perspectives
Authors: Cicoira F. , Santato C.
Published: October 2007

Light emitting field effect transistors based on molecular and polymeric organic semiconductors are multifunctional devices that integrate light emission with the current modulating function of a transistor. The planar geometry of organic light emitting field effect transistors (OLEFETs) offers direct access to the light emission region, providing a unique experimental configuration to investigate fundamental optical and electronic properties in organic semiconductors. OLEFETs show great potential for technological applications such as active matrix full color electroluminescent displays. In this Feature Article we review advances in OLEFETs since their first demonstration in 2003 and we highlight exciting challenges associated with their future development.
Nanoparticles Prepared by Salt Vapor‐Solvent Vapor Cocondensation and Controlled Nucleation: Metal Sulfides (ZnS, CdS, CdSe, PbS), and Metal Halide (LiF). Size, Aggregates, Structures, Digestive Ripening, Superlattices, and Impregnations
Authors: Heroux D. , Ponce A. , Cingarapu S. , Klabunde K. J.
Published: October 2007

A versatile method for the production of gram quantities of nanocrystals of metal sulfides and metal halides has been developed, based on vaporization of the bulk materials followed by controlled nucleation of the molecular vapor species in cold solvent matrices (cocondensate). This approach worked well with ZnS, CdS, CdSe, CdTe, SnS, PbS, and LiF as examples, and is applicable for a large number of semiconductors, ionic salts, as well as metals. Choice of solvent (polar or non‐polar), vaporization rate, and rate of warm‐up of the cocondensate (period of nucleation) allows some control of crystallite size, aggregate size, and surface area. Interestingly, polar solvents lead to smaller nanocrystals, but larger, less porous aggregates. Also, molar mass of the molecular species has an effect on crystallite size, with heavier molecules giving smaller crystals, apparently due to slower migration in the warming cocondensate. Studies of sintering temperature and crystal growth have shown the nanocrystals are quite thermally stable. Addition of ligands, such as thiols, followed by heating in solvent (digestive ripening) has allowed more monodisperse materials to be formed. Finally, this molecular vapor synthesis approach can be used for impregnating semiconductors (CdS, CdSe) of controlled crystal size on solid supports, such as TiO2 or SiO2.
Chemical modification of multiwalled carbon nanotube with the liquid phase method
Authors: Chiu Wei‐Ming , Chang You‐An
Published: October 2007

In this study, multiwalled carbon nanotubes (MWNTs) were purified by using chemical method with different proportion of nitric acid and sulfuric acid liquid phase mixture. Carboxyl groups and other functional groups could be modified on the MWNTs surface. However, oxidation can damage the structure of carbon atoms on the surface of the carbon nanotube. Furthermore, the characteristic properties of MWNTs specimens were demonstrated by Raman spectrograph and Fourier transform infrared spectrum. The thermal properties and morphology of MWNTs were checked by Thermogravimetric analysis and Scanning electron microscope. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
UV polymerization‐based surface modification technique for the production of bioactive packaging
Authors: Kothapalli A. , Morgan M. , Sadler G.
Published: October 2007

The term bio‐active packaging refers to a packaging material that has been modified by the attachment or immobilization of bioactive components on the food contact surface. This article describes a novel, economical, and feasible technique for embedding bioactive components in energy curable food contact resins. While the technique is versatile and potentially applicable to any antimicrobial or bioactive compound; the proof of concept discussed in this article has focused on enzyme immobilization. Glucose oxidase (GOx) and catalase were used as representative enzymes. These oxidoreductases are very sensitive to inactivation by extrinsic factors and therefore present a challenging model for immobilization. Embedding of activity occurred via UV polymerization of commercial polymer coatings. The efficiency of immobilization and the performance of bioactive packaging were tested in both food simulants and actual food products. In both cases immobilization resulted in food contact surfaces with high retained enzyme activity as demonstrated by oxygen removal. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis, characterization, and thermal properties of tris (3‐aminophenyl) phosphine oxide‐based nadimide resins
Authors: Darshan  , Sharma Pooja , Malhotra Priti , Narula A. K.
Published: October 2007

This article describes the synthesis, characterization, and thermal properties of nadimides obtained by reacting endo‐5‐norbornene‐2,3‐dicarboxylic acid anhydride (nadic anhydride) (NA), 4,4′‐oxodiphthalic anhydride (ODA), 1,4,5,8‐naphthalene tetra carboxylic dianhydride (NTDA) in glacial acetic acid/DMF. Structural characterization of the resins was done by elemental analysis, IR, 1H‐NMR, and 13C‐NMR. The DSC scan showed the endothermic transition in the temperature range of 120–270°C. Multistep decomposition was observed in the TG scan of uncured resins in nitrogen atmosphere. Isothermal curing of the resins was done at 250 and 300°C for 1 h in an air atmosphere. These cured resins were stable to (350 ± 30)°C and decomposed in a single step above this temperature. This may be due to the retro Diels Alder (RDA) reaction. The char yield of the resins increased significantly on curing. The char yield was highest for P‐2N resin and this could be due to the presence of rigid skeleton i.e. naphthalene. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Effect of microencapsulated curing agents on the curing behavior for diglycidyl ether of bisphenol A epoxy resin systems
Authors: Xu Hongxia , Fang Zhengping , Tong Lifang
Published: October 2007

Microcapsules containing a curing agent, 2‐phenyl imidazole (2PZ), for a diglycidyl ether of bisphenol A (DGEBA) epoxy resin were prepared by a solid‐in‐oil‐in‐water emulsion solvent evaporation technique with poly(methyl methacrylate) (PMMA) as a polymeric wall. The mean particle size of the microcapsules and the concentration of 2PZ were about 10 μm and nearly 10 wt %, respectively. The onset cure temperature and peak temperature of the DGEBA/2PZ–PMMA microcapsule system appeared to increase by nearly 30 and 10°C, respectively, versus those of the DGEBA/2PZ system because of the increased reaction energy of curing. The former could take more than 3 months at room temperature, whereas the latter was cured after only a week. The values of the reaction order (a curing kinetic parameter) for DGEBA/2PZ and DGEBA/2PZ–PMMA microcapsules were quite close, and this showed that the curing reactions of the two samples proceeded conformably. The curing mechanism was investigated, and a two‐step initiation mechanism was considered: the first was assigned to adduct formation, whereas the second was due to alkoxide‐initiated polymerization. The glass‐transition temperature of DGEBA/2PZ was 165.2°C, nearly 20°C higher than the glass‐transition temperatures of DGEBA/2PZ–PMMA microcapsules and DGEBA/2PZ/PMMA microspheres, as determined by differential scanning calorimetry measurements. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Shakbazian Compact Groups: Mass‐to‐light ratios and mass distribution models: I. ShCG 362 and ShCG 166
Authors: Gimeno G. , Campos M. , Díaz R. , Calderón J.
Published: October 2007

We present results of photometric observations under excellent seeing conditions of Shakbazian Compact Groups. We obtained the seeing‐unconvolved surface brightness profiles of individual galaxies in the I band. We also determined the B – I color index for each galaxy, and investigated the presence of cores in the early type galaxies. We constructed models for the mass distribution of the individual galaxies. The mass‐to‐light (𝔐/L) ratios have normal values, and the conclusion that these groups have little dark matter is confirmed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photospheric and chromospheric activity on EY Dra
Authors: Korhonen H. , Brogaard K. , Holhjem K. , Ramstedt S. , Rantala J. , Thöne C.C. , Vida K.
Published: October 2007

Magnetic activity in the photosphere and chromosphere of the M dwarf EY Dra is studied and possible correlations between the two are investigated using photometric observations in the V and R bands and optical and near infrared spectroscopy. The longitudinal spot configuration in the photosphere is obtained from the V band photometry, and the chromospheric structures are investigated using variations in the Hα line profile and observations of the Paschen β line. The shape of the V band light‐curve indicates two active regions on the stellar surface, about 0.4 in phase apart. The spectroscopic observations show enhanced Hα emission observed close to the phases of the photometrically detected starspots. This could indicate chromospheric plages associated with the photospheric starspots. Some indications of prominence structures are also seen. The chromospheric pressure is limited to log mTR < –4 based on the non‐detection of emission in the Paschen β wavelength region. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A near‐infrared/optical/X‐ray survey in the centre of σ Orionis
Authors: Caballero J.A.
Published: October 2007

Because of the intense brightness of the OB‐type multiple star system σ Ori, the low‐mass stellar and substellar populations close to the centre of the very young σ Orionis cluster is poorly know. I present an IJHKs survey in the cluster centre, able to detect from the massive early‐type stars down to cluster members below the deuterium burning mass limit. The near‐infrared and optical data have been complemented with X‐ray imaging. Ten objects have been found for the first time to display high‐energy emission. Previously known stars with clear spectroscopic youth indicators and/or X‐ray emission define a clear sequence in the I vs. I – Ks diagram. I have found six new candidate cluster members that follow this sequence. One of them, in the magnitude interval of the brown dwarfs in the cluster, displays X‐ray emission and a very red J – Ks colour, indicative of a disc. Other three low‐mass stars have excesses in the Ks band as well. The frequency of X‐ray emitters in the area is 80±20 %. The spatial density of stars is very high, of up to 1.6±0.1 arcmin–2. There is no indication of lower abundance of substellar objects in the cluster centre. Finally, I also report two cluster stars with X‐ray emission located at only 8000–11000 AU to σ Ori AB, two sources with peculiar colours and an object with X‐ray emission and near‐infrared magnitudes similar to those of previously‐known substellar objects in the cluster. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Recent photometry of symbiotic stars
Authors: Skopal A. , Vaňko M. , Pribulla T. , Chochol D. , Semkov E. , Wolf M. , Jones A.
Published: October 2007

We present new photometric observations of 15 symbiotic stars covering their last orbital cycle(s) from 2003.9 to 2007.2. We obtained our data by both classical photoelectric and CCD photometry. Main results are: EG And brightened by ∼0.3 mag in U from 2003. A ∼0.5 mag deep primary minimum developed in the U light curve (LC) at the end of 2006. ZAnd continues its recent activity that began during the 2000 autumn. A new small outburst started in summer of 2004 with a peak U magnitude of ∼ 9.2. During the spring of 2006 the star entered a massive outburst. It reached its historical maximum at U ∼ 8.0 in 2006 July. AEAra erupted in 2006 February with Δmvis ∼ 1.2 mag. BF Cyg entered a new active stage in 2006 August. A brightness maximum (U ∼ 9.4) was measured during 2006 September. CH Cyg persists in a quiescent phase. During 2006 June–December a ∼ 2 mag decline in all colours was measured. CI Cyg started a new active phase during 2006 May–June. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
No effect of an UMTS mobile phone‐like electromagnetic field of 1.97 GHz on human attention and reaction time
Authors: Unterlechner Manuela , Sauter Cornelia , Schmid Gernot , Zeitlhofer Josef
Published: October 2007

Several studies in the past reported influences of electromagnetic emissions of GSM phones on reaction time in humans. However, there are currently only a few studies available dealing with possible effects of the electromagnetic fields emitted by UMTS mobile phones. In our study, 40 healthy volunteers (20 female, 20 male), aged 26.0 years (range 21–30 years) underwent four different computer tests measuring reaction time and attention under three different UMTS mobile phone‐like exposure conditions (two exposure levels plus sham exposure). Exposure of the subjects was accomplished by small helical antennas operated close to the head and fed by a generic signal representing the emissions of a UMTS mobile phone under constant receiving conditions as well as under a condition of strongly varying transmit power. In the high exposure condition the resulting peak spatial average exposure of the test subjects in the cortex of the left temporal lobe of the brain was 0.63 W/kg (min. 0.25 W/kg, max. 1.49 W/kg) in terms of 1 g averaged SAR and 0.37 W/kg (min. 0.16 W/kg, max. 0.84 W/kg) in terms of 10 g averaged SAR, respectively. Low exposure condition was one‐tenth of high exposure and sham was at least 50 dB below low exposure. Statistical analysis of the obtained test parameters showed that exposure to the generic UMTS signal had no statistically significant immediate effect on attention or reaction. Therefore, this study does not provide any evidence that exposure of UMTS mobiles interferes with attention under short‐term exposure conditions. Bioelectromagnetics 29:145–153, 2008. © 2007 Wiley‐Liss, Inc.
New Regiocontrolled Synthesis of Functionalized Pyrroles from 2‐Azetidinone‐Tethered Allenols
Authors: Alcaide Benito , Almendros Pedro , Carrascosa Rocío , Redondo María C.
Published: October 2007

A new one‐pot approach to synthesize densely substituted racemic and enantiopure pyrroles from β‐lactams has been developed. The approach relies on the regiocontrolled cyclization of β‐allenamine intermediates derived from the ring opening of 2‐azetidinone‐tethered allenols. In this approach four points of diversity are introduced, one of which is the position of the allene moiety on the β‐lactam ring.
Amphiphilic and Magnetic Properties of a New Class of Cluster‐Bearing [L2Cu4(μ4‐O)(μ2‐carboxylato)4] Soft Materials
Authors: Shakya Rajendra , Hindo Sarmad Sahiel , Wu Libo , Ni Suolong , Allard Marco , Heeg Mary Jane , da Rocha Sandro R. P. , Yee Gordon T. , Hratchian Hrant P. , Verani Cláudio N.
Published: October 2007

A general approach toward amphiphilic systems bearing multimetallic clusters and their ability to form Langmuir–Blodgett films is presented. The synthetic strategy to stabilize these clusters involves the use of a ligand (HL) containing an N2O‐donor set and long octadecanoic chains to obtain the carboxylate‐supported [L2Cu4(μ4‐O)(μ2‐OAc)4]⋅EtOH (1) and [L2Cu4(μ4‐O)(μ2‐OBz)4] (2) in which OAc− and OBz− represent acetate (1) and benzoate (2) co‐ligands. These species were thoroughly characterized and had their structures solved by X‐ray crystallography. We observed that the μ‐oxo Cu4 cluster is antiferromagnetically coupled and used broken‐symmetry density functional theory (DFT) calculations to describe the main superexchange pathways of the tetracopper core. We also describe the amphiphilic properties of the ligand and the cluster‐containing systems by means of area versus pressure isotherms and show that these cluster‐bearing species can be transferred onto solid substrates yielding homogeneous Langmuir–Blodgett films, as characterized by atomic force microscopy and contact angle measurements.
Breaking Symmetry: Spontaneous Resolution of a Polyoxometalate
Authors: Hou Yu , Fang Xikui , Hill Craig L.
Published: October 2007

A chiral polyoxometalate [Hf(PW11O39)2]10− (1) has been prepared and structurally characterized. It crystallizes in the chiral space group P21212, as a conglomerate of two enantiomerically pure crystals in the absence of any chiral source. The absolute configuration of 1 was determined from the Flack parameter by X‐ray crystallography. The structure of 1 comprises two lacunary [PW11O39]7− units, each functioning as a tetra‐dentate ligand sandwiching an 8‐coordinate HfIV centre in a distorted square antiprismatic geometry. Optically active crystals of both enantiomers were spectroscopically distinguishable by means of solid state circular dichroism spectroscopy. This hafnium‐substituted polyoxometalate (POM), 1, shows that spontaneous chiral resolution, a rare phenomenon, can be operable in POM systems.
Primary prevention of eating disorders: A constructivist integration of mind and body strategies
Authors: Scime Melinda , Cook‐Cottone Catherine
Published: October 2007

Objective:

This study investigated the impact of a primary prevention program for eating disorders aimed at fifth‐grade females. The curriculum was based on empirically validated risk and protective factors and incorporated interactive discourse, yoga, and relaxation into 10 weekly sessions.

Method:

Pre‐ and post‐test data from five groups conducted over 2 years were combined for a total of 75 participants. Data were also collected from 69 control group participants.

Results:

Results indicate completion of the group resulted in a significant decrease on scales from the Eating Disorder Inventory‐2 measuring body dissatisfaction and bulimia, as well as an increase on the Social scale of the Multidimensional Self‐Concept Scale.

Conclusion:

The results demonstrate mixed support for the Girls' Group prevention program. Implications for practice and future research are discussed. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2008