bluuebunny/crossref_metadata_2025 huggingface dataset:
Chitosan/clay nanocomposite film preparation and characterization
Authors: Xu Yixiang , Ren Xi , Hanna Milford A.
Published: December 2005

Nanocomposites of chitosan and nanoclays (MMT‐Na+ and Cloisite 30B) were prepared by solvent casting. The structural properties, thermal behaviors, and mechanical properties were characterized using X‐ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy, differential scanning calorimetry, thermogravimetry analyses, and an Instron universal testing machine. XRD and TEM results indicated that an exfoliated structure was formed with addition of small amounts of MMT‐Na+ to the chitosan matrix. Intercalation along with some exfoliation occurred with up to 5 wt % MMT‐Na+. Micro‐scale composite (tactoids) formed when Cloisite 30B was added to the chitosan matrix. Surface roughness increased with addition of a small amount of clay. Tensile strength of a chitosan film was enhanced and elongation‐at‐break decreased with addition of clay into the chitosan matrix. Melt behavior and thermal stability did not change significantly with addition of clays. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1684–1691, 2006
4‐Acetamidophenyl acrylate copolymers with acrylonitrile and N‐vinyl‐2‐pyrrolidone: Synthesis, characterization, and reactivity ratios
Authors: Reddy B. S. R. , Balasubramaniam S. , Suriyan M. R.
Published: December 2005

4‐Acetamidophenyl acrylate (APA) was synthesized and characterized by IR, 1H and 13C NMR spectroscopies. Homo‐ and copolymers of APA with acrylonitrile (AN) and N‐vinyl‐2‐pyrrolidone (NVP) were prepared by a free radical polymerization. All the copolymer compositions have been determined by 1H NMR technique, and the reactivity ratios of the monomer pairs have been evaluated using the linearization methods Fineman–Ross, Kelen–Tudos, and extended Kelen–Tudos. Nonlinear error‐in‐variable model (EVM) method was used to compare the reactivity ratios. The reactivity ratios for copoly(APA–AN) system were APA(r1) = 0.70 and AN(r2) = 0.333, and for copoly(APA–NVP) system the values were APA(r1) = 4.99 and NVP(r2) = 0.019. Thermal stability and molecular weights of the copolymers are reported. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1919–1927, 2006
Influences of the polymerization ingredients on the porous morphology of soap‐free poly(methyl methacrylate/ethyl acrylate/methacrylic acid) seeded latex particles
Authors: Kang Kai , Kan Cheng You , Du Yi , Liu De Shan
Published: December 2005

Monodispersed soap‐free poly(methyl methacrylate/ethyl acrylate/methacrylic acid) latex particles were synthesized by the seeded emulsion polymerization of methyl methacrylate, ethyl acrylate, and methacrylic acid (MAA), and particles with a porous morphology were obtained after an alkali posttreatment. The effects of the unsaturated acid and crosslinking agent on the properties and morphology of the latex particles were investigated. The results showed that the particle size decreased and its distribution widened when the concentration of MAA was greater than 10.0 mol % or the concentration of ethylene glycol dimethacrylate (EGDMA) was greater than 1.5%. When more than 4.0 mol % MAA was used, a porous structure could be detected clearly under a transmission electron microscope, and the particle volume and pore size first gradually increased to a maximum and then decreased rapidly with an increase in the MAA concentration. The porous morphology disappeared completely as the MAA concentration reached 16.0 mol %. A multihollow morphology was generated when the EGDMA concentration exceeded 1.0%, and the particle volume decreased monotonously with the concentration of EGDMA increased. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1934–1939, 2006
Effect of alkylammonium salt on the dispersion and properties of Poly(p‐phenylene sulfide)/clay nanocomposites via melt intercalation
Authors: Zou Hao , Xu Wei , Zhang Qing , Fu Qiang
Published: December 2005

To explore the possibility of making poly(p‐phenylene sulfide) (PPS) nanocomposites via melt intercalation and improving the mechanical properties of PPS, in this study we first modified clay (montmorillonite) with alkylammonium salt by cation exchange and then mixed the modified clay together with the PPS matrix by twin‐screw extrusion. Because the PPS/clay composites were made at a high temperature (300°C), thermogravimetric analysis experiments were carried out first to check the thermal stability of the alkylammonium salt treated clay and the obtained composites. Possible degradation of the alkylammonium salt during processing caused a decrease in the interlayer spacing of the clay. Scanning electron microscopy, transmission electron microscopy, and X‐ray diffraction were used to investigate the dispersion of the clay sheet in the matrix. The clay layers were homogeneously dispersed in the PPS matrix with a nanometer scale, and an exfoliated structure was achieved at a low load of clay. The alkylammonium salt modifier enhanced the interaction between the PPS and clay on the one hand, but on the other hand, it also acted as a plasticizer and caused decreases in the glass‐transition temperature and tensile properties. More work is needed to find a modifier and processing conditions by which the modifier can help the dispersion of clay and also be completely degraded after the formation of an exfoliated structure. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1724–1731, 2006
Application of time–temperature superposition principle to polymer transition kinetics
Authors: Cheng Rongshi , Yang Hu
Published: December 2005

The time–temperature equivalence equation is deduced simply in view of the transition kinetics of a polymer. The independent variables time and temperature are separated in the two sides of the resulting equation. Thus, a physical property of the polymer, which is temperature dependent, can be matched with the theoretical calculated curve from a supposed model of transition kinetics in which only time is involved as the independent variable. By comparing different models, one may judge which model is probably more correct. The procedure of data fitting is described. As an application example, the measured viscosity data at different temperatures for the coil–globule transition of poly(N‐isopropylacrylamide) in aqueous solution is tested to judge its transition mechanism. A transition mechanism involving a two‐stage reversible reaction fits the experimental data in a satisfactory way. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1767–1772, 2006
Essential work of fracture evaluation of fracture behavior of glass bead filled linear low‐density polyethylene
Authors: Yang Wei , Xie Bang‐Hu , Shi Wei , Li Zhong‐Ming , Liu Zheng‐Ying , Chen Jun , Yang Ming‐Bo
Published: December 2005

The effect of the glass bead (GB) size and bead content on the fracture behavior of GB‐filled linear low‐density polyethylene (LLDPE) composites was evaluated by means of the essential work of fracture (EWF). The results indicated the specific EWF (we) is lower for the composites than that of pure LLDPE and the obtained we values do not show significant differences for the filled samples with different GB diameters. The non‐EWF or plastic work (βwp) also decreased with the addition of GBs, indicating that less energy is absorbed during the fracture process for the composites filled with different diameter GBs. For the composites filled with GBs of different contents, the we decreased with increasing GB contents and the βwp that was higher than that of pure LLDPE at relatively low contents also decreased with the content of GBs. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1781–1787, 2006
Electrodialytic removal of nitrates and hardness from simulated mixtures using ion‐exchange membranes
Authors: Nataraj S. K. , Hosamani K. M. , Aminabhavi T. M.
Published: December 2005

A novel electrodialysis (ED) pilot plant unit coupled with a membrane stack containing 11 cation‐exchange and 10 anion‐exchange membranes is used for the removal of nitrates and hardness from simulated aqueous mixtures containing salts that are usually encountered in brackish water. The removal of high nitrates and water hardness is performed in 150 min of ED under three constant applied voltages at room temperature. The limiting current density is obtained for sodium nitrate and calcium chloride mixtures in dilute solution. In order to check the efficacy of the ED method, parameters like the applied potential are varied at constant flow rates. The efficiency of the ED method depends on the applied potential. Possible applications of ED are discussed for the removal of contaminants below the minimum contaminant level of drinking water. The ED method used here is satisfactory to produce good quality drinking water from a simulated mixture by removing the unwanted ions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1788–1794, 2006
Expression of caveolin‐1 in the rat temporomandibular joint
Authors: Nozawa‐Inoue Kayoko , Suzuki Akiko , Amizuka Norio , Maeda Takeyasu
Published: December 2005

This immunocytochemical study revealed the expression of caveolin‐1, a major protein of caveolae, in the rat temporomandibular joint. In the synovial lining layer, immunoreactive products for caveolin‐1 were detected on the cell membrane of the fibroblast‐like type B cells, as confirmed by immunocytochemistry for heat shock protein 25. The cells in the articular disk, the articular layer, and zone of proliferation of the mandibular condyle also showed intense immunoreactions for caveolin‐1. © 2005 Wiley‐Liss, Inc.
Specializations of the granular prefrontal cortex of primates: Implications for cognitive processing
Authors: Elston Guy N. , Benavides‐Piccione Ruth , Elston Alejandra , Zietsch Bendan , Defelipe Javier , Manger Paul , Casagrande Vivien , Kaas Jon H.
Published: December 2005

The biological underpinnings of human intelligence remain enigmatic. There remains the greatest confusion and controversy regarding mechanisms that enable humans to conceptualize, plan, and prioritize, and why they are set apart from other animals in their cognitive abilities. Here we demonstrate that the basic neuronal building block of the cerebral cortex, the pyramidal cell, is characterized by marked differences in structure among primate species. Moreover, comparison of the complexity of neuron structure with the size of the cortical area/region in which the cells are located revealed that trends in the granular prefrontal cortex (gPFC) were dramatically different to those in visual cortex. More specifically, pyramidal cells in the gPFC of humans had a disproportionately high number of spines. As neuron structure determines both its biophysical properties and connectivity, differences in the complexity in dendritic structure observed here endow neurons with different computational abilities. Furthermore, cortical circuits composed of neurons with distinguishable morphologies will likely be characterized by different functional capabilities. We propose that 1. circuitry in V1, V2, and gPFC within any given species differs in its functional capabilities and 2. there are dramatic differences in the functional capabilities of gPFC circuitry in different species, which are central to the different cognitive styles of primates. In particular, the highly branched, spinous neurons in the human gPFC may be a key component of human intelligence. © 2005 Wiley‐Liss, Inc.
Pattern of infliximab utilization in rheumatoid arthritis patients at an academic medical center
Authors: Agarwal Sandeep K. , Maier Agnes L. , Chibnik Lori B. , Coblyn Jonathan S. , Fossel Anne , Lee Ryan , Fanikos John , Fiumara Karen , Lowry Colleen , Weinblatt Michael E.
Published: December 2005

Objective

To investigate the pattern of use of infliximab with an emphasis on treatment escalation and the durability of infliximab use in the management of rheumatoid arthritis (RA) in an academic setting.

Methods

We conducted a retrospective review of pharmacy and medical records of 183 patients with RA who received at least 1 infliximab infusion at the infusion centers of the Brigham and Women's Hospital. Treatment escalation was defined as an increase in the dosage of infliximab to >3 mg/kg and/or a decrease in the dosing interval to <7 weeks between infusions.

Results

A total of 183 patients with RA received infliximab infusions for a mean ± SD duration of 58.2 ± 56.6 weeks. Infliximab was discontinued in 48% of the patients during the first year of therapy and in 67% of the patients overall. A total of 126 patients had a treatment escalation, including 25 patients with a dose increase, 35 patients with a decrease in the interval, and 66 patients with both. Infliximab treatment was associated with a decrease in corticosteroid and methotrexate doses. Patients who had a treatment escalation were more likely to continue infliximab infusions compared with patients without a treatment escalation (odds ratio 2.0, 95% confidence interval 1.0–4.1).

Conclusion

The use of infliximab may be an effective treatment for RA; however, a substantial number of patients will discontinue its use. Treatment escalation is commonly used in the management of RA with infliximab and is associated with longer duration of infliximab use.
Pain as a mediator of sleep problems in arthritis and other chronic conditions
Authors: Power J. Denise , Perruccio Anthony V. , Badley Elizabeth M.
Published: December 2005

Objective

To examine the associations between arthritis and insomnia symptoms and unrefreshing sleep, as well as the role of pain as a mediator of these relationships.

Methods

Analyses were conducted on the cross‐sectional, nationally representative, weighted sample of adults ≥18 years of age (n = 118,336) in the 2000/2001 Canadian Community Health Survey. Four logistic regression models were estimated for each sleep problem (model 1: arthritis only; model 2: model 1 + sociodemographic characteristics, lifestyle factors, and other chronic conditions; model 3: model 2 + mental health [stress, depression]; and model 4: model 3 + pain). Mediation by pain was quantified by the percentage change in the effect of arthritis on a particular sleep problem by comparing models 3 and 4.

Results

The prevalence of insomnia symptoms and unrefreshing sleep in persons with arthritis was 24.8% and 11.9%, respectively. These estimates are twice as high as those for persons without arthritis. In multivariate regression analyses, the addition of pain decreased the effect of arthritis by 53% (insomnia symptoms) and 64% (unrefreshing sleep). The effect of arthritis was still statistically significant in these models, suggesting that pain is a partial mediator of these relationships.

Conclusion

Insomnia symptoms and unrefreshing sleep affect a considerable proportion of individuals with arthritis. Pain mediates a substantial amount of the relationship between arthritis and sleep problems. Better pain management could significantly improve sleep in individuals with arthritis.
Impact of shoulder, elbow, and knee joint involvement on assessment of rheumatoid arthritis using the American College of Rheumatology Core Data Set
Authors: Tanaka Eiichi , Saito Akira , Kamitsuji Shigeo , Yamada Toru , Nakajima Ayako , Taniguchi Atsuo , Hara Masako , Tomatsu Taisuke , Yamanaka Hisashi , Kamatani Naoyuki
Published: December 2005

Objective

To determine the most sensitive scoring method for assessment of rheumatoid arthritis (RA) disease activity using the American College of Rheumatology Core Data Set.

Methods

The subjects were 4,530 patients with RA (mean age 57.9 years, mean disease duration 12.7 years) who participated in a large observational cohort study of RA patients. The 68 joints assessed were classified into 15 joint areas, and each joint variable was categorized based on the presence or absence of swelling or pain in these areas. Multiple linear regression and analysis of variance were used to evaluate the significance of effects of these 15 joint areas on variables for assessment of RA disease activity such as patient's assessment of pain on a visual analog scale (VAS), patient's and physician's global assessment of disease activity on a VAS, HAQ (Health Assessment Questionnaire), and Japanese HAQ.

Results

Although the 3 most frequently affected joints were the wrist, metacarpophalangeal joints, and proximal interphalangeal joints, the 5 joints with the largest contributions to all of the variables assessed for disease activity were the shoulder, elbow, and knee joints, followed by the wrist and ankle joints. The combination of shoulder, elbow, and knee joints accounted for approximately 70% of the contribution to all the variables, while addition of the wrist and ankle joints increased this value to approximately 90%.

Conclusion

Scoring for assessment of RA disease activity would be more sensitive if separate joints such as the shoulder, elbow, knee, wrist, and ankle joints were weighted differently.
Oxygen enhances lethal effect of high‐intensity, ultrashort electrical pulses
Authors: Walker Kerfoot , Pakhomova Olga N. , Kolb Juergen , Schoenbach Karl S. , Stuck Bruce E. , Murphy Michael R. , Pakhomov Andrei G.
Published: December 2005

The study explored the effect of ambient oxygen on mammalian cell survival after exposure to 10 ns duration, high voltage electrical pulses (nsEP, 80–90 or 120–130 kV/cm; 200–400 pulses per exposure). Cell samples were equilibrated with pure nitrogen, atmospheric air, or pure oxygen prior to the nsEP treatment and were returned to the incubator (air + 5% CO2) shortly after the exposure. The experiments established that survival of hypoxic Jurkat and U937 cells exceeded that of air‐equilibrated controls about twofold (P < .01). Conversely, saturation of the medium with oxygen prior to exposure decreased Jurkat cell survival about 1.5 times, P < .01. Attenuation of the cytotoxic effect under hypoxic conditions resembled a well‐known effect of oxygen on cell killing by sparsely ionizing radiations and may be indicative of the similarity of underlying cell damage mechanisms. Bioelectromagnetics 27:221–225, 2006. Published 2005 Wiley‐Liss, Inc.
Propionate‐regulated high‐yield protein production in Escherichia coli
Authors: Lee Sung Kuk , Keasling Jay D.
Published: December 2005

A new expression system containing the Salmonella enterica prpBCDE promoter (PprpB) responsible for expression of the propionate catabolic genes (prp BCDE) and prpR encoding the positive regulator of this promoter has been developed and tested. The main features of the expression system compared to those based on the bacteriophage T7 promoter are low background expression and high induced expression in Escherichia coli strains BL21, BL21(DE3), MG1655, and W3110. In addition, propionate is an inexpensive, simple‐to‐use, nontoxic inducer that is attractive for large‐scale protein production. Hence, this new system is highly complementary to the widely used T7 promoter‐driven expression systems. © 2005 Wiley Periodicals, Inc.
Impact of evidence‐based interdisciplinary guidelines on testis cancer management
Authors: Schrader Andres Jan , Ohlmann Carsten‐Henning , Rossmanith Sandra , Hofmann Rainer , Heidenreich Axel
Published: December 2005

BACKGROUND

In 1999, interdisciplinary evidence‐based guidelines were elaborated for treatment of germ cell tumors in Germany. The aims of the current study were to analyze failures in diagnosis and therapy and to demonstrate the influence of guidelines on individual therapeutic approaches and clinical outcome. Therefore, patient collectives treated before the introduction of guidelines (Group A, 1990–1999, n = 234) and those thereafter (Group B, 2000–2002, n = 84) were compared for recurrence and survival.

METHODS

In both groups, medical and/or surgical treatment and clinical outcome were evaluated for therapeutic mistakes and violations of guidelines. These were analyzed for their clinical consequences.

RESULTS

There was no significant difference between groups concerning median age of patients or clinical stage before therapy. Altogether, 27.8% and 8.3% of all patients in Group A and B, respectively, displayed therapeutic mistakes (P < 0.005); 63% of these patients in Group A and 100% of these patients in Group B received an overtreatment. In Group A, 19/234 (8.1%) patients relapsed and 53% of these patients had been treated insufficiently (P < 0.005). Advanced disease caused the death of 3/234 patients in this study. As of this writing, only 3 of 84 (3.6%) patients in Group B have relapsed, and no patient has died because of tumor or consecutive treatment.

CONCLUSIONS

The integration of interdisciplinary evidence‐based guidelines for treatment of testicular germ cell tumors has led to significant reduction of both overtreatment and treatment failure and/or relapse that were due to inappropriate primary therapy. Evidence‐based guidelines should serve as internal quality controls in all institutions treating patients with testicular germ cell tumors. Cancer 2006. © 2005 American Cancer Society.
Activation barriers for DNA alkylation by carcinogenic methane diazonium ions
Authors: Ekanayake Kaushalya S. , Lebreton Pierre R.
Published: December 2005

Methylation reactions of the DNA bases with the methane diazonium ion, which is the reactive intermediate formed from several carcinogenic methylating agents, were examined. The SN2 transition states of the methylation reactions at N7, N3, and O6 of guanine; N7, N3, and N1 of adenine; N3 and O2 of cytosine; and O2 and O4 of thymine were calculated using the B3LYP density functional method. Solvation effects were examined using the conductor‐like polarizable continuum method and the combined discrete/SCRF method. The transition states for reactions at guanine N3, adenine N7, and adenine N1 are influenced by steric interactions between the methane diazonium ion and exocyclic amino groups. Both in the gas phase and in aqueous solution, the methylation reactions at N atoms have transition states that are looser, and generally occur earlier along the reaction pathways than reactions at O atoms. The forming bonds in the transition states in water are 0.03 to 0.13 Å shorter than those observed in the gas phase, and the activation energies are 13 to 35 kcal/mol higher. The combined discrete/SCRF solvation energy calculations using base‐water complexes with three water molecules yield base solvation energies that are larger than those obtained from the CPCM continuum method, especially for cytosine. Reactivities calculated using barriers obtained with the discrete/SCRF method are consistent with the experimentally observed high reactivity at N7 of guanine. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 277–286, 2006
Nitro‐blue tetrazolium staining of starch‐synthesizing enzymes in developing rice grains
Authors: Jeng TL , Tseng TH , Wang CS , Chen CL , Sung JM
Published: December 2005

An in situ nitro‐blue tetrazolium (NBT) staining method was used to locate the activities of enzymes involved in starch synthesis in developing grains of field grown rice (Oryza sativa L.) cultivar Tainung 67 and its early ripening mutant SA 419. The results indicated that all the tested enzymes, including sucrose synthase, invertase, hexokinase, ADP‐glucose pyrophosphorylase, UDP‐glucose pyrophosphorylase and starch synthase, were detectable in developing rice endosperms by using NBT staining. The activity of these enzymes was also measurable by using chemical assays. The expression of enzyme activity, as indicated by the formation of blue formazan precipitate, in growing grain of Tainung 67 were visualized in entire endosperm at 11 days after anthesis (DAA). However, NBT staining shifted from central to peripheral region of endosperm after 18 DAA, and the staining disappeared at 25 DAA. Similar staining patterns were also observed in the growing grains of mutant SA 419, but the shift of staining from central to peripheral endosperm occurred at 11 DAA. Electron microscopy examinations showed that the growing patterns of starch granules, sampled from central and peripheral regions of endosperm, varied between two cultivars, with SA 419 growing faster than Tainung 67. Both cultivars showed that the shifts of NBT staining pattern coincided with the changes in the growing pattern of starch granules located in central and peripheral regions of endosperms. The NBT staining results showed that the activities of sucrose to starch conversion enzymes in mutant SA 419 declined and disappeared earlier than its wild‐type Tainung 67 and therefore it ripened earlier than cultivar Tainung 67. Copyright © 2005 Society of Chemical Industry
On the evolution of key physiological and physicochemical parameters throughout the maturation of Burlat cherry
Authors: Remon Sara , Ferrer Ana , Venturini María E , Oria Rosa
Published: December 2005

We have studied the ripening process of Burlat sweet cherry during two consecutive growing seasons in order to identify its main specific characteristics. An increase in ethylene production is consistently observed when the fruit reaches an acceptable degree of ripeness. This ethylene peak clearly divides the ripening process into two distinct phases with markedly different behaviour of all of the parameters measured in this study: respiration rate, titratable acidity, soluble solids content, firmness, colour, pectolytic and oxidation enzymes and anthocyanin content. Copyright © 2005 Society of Chemical Industry
Steady state of gradient echo sequences with radiofrequency phase cycling: Analytical solution, contrast enhancement with partial spoiling
Authors: Ganter Carl
Published: December 2005

Spoiled gradient echo sequences can only reach a homogeneous steady state if sufficiently strong crusher gradients are used in combination with RF phase cycling (RF spoiling). However, the signal depends quite sensitively on the chosen phase increment ϕ and—lacking analytical solutions—numerical simulations must be used to study the transient and steady‐state magnetization. For the steady state an exact analytical solution is derived, which holds for arbitrary sequence and tissue parameters. Besides a considerably improved computation performance, the analytical approach enables a better understanding of the complicated dependence on ϕ. For short repetition times (TR) the regime of small ϕ turns out to be particularly interesting: It is shown that the typical ϕc, where RF spoiling starts to become effective, is essentially inversely proportional to T2. This tissue dependence implies that contrasts can be considerably larger with partial spoiling (ϕ ≈ ϕc) than with conventional RF spoiling (ϕ ≫ ϕc). As an example, the uptake of contrast agents in tissues is investigated. For typical parameters a considerably improved contrast enhancement can be obtained, both theoretically and experimentally. Magn Reson Med, 2006. © 2005 Wiley‐Liss, Inc.
Highly constrained backprojection for time‐resolved MRI
Authors: Mistretta C. A. , Wieben O. , Velikina J. , Block W. , Perry J. , Wu Y. , Johnson K. , Wu Y.
Published: December 2005

Recent work in k‐t BLAST and undersampled projection angiography has emphasized the value of using training data sets obtained during the acquisition of a series of images. These techniques have used iterative algorithms guided by the training set information to reconstruct time frames sampled at well below the Nyquist limit. We present here a simple non‐iterative unfiltered backprojection algorithm that incorporates the idea of a composite image consisting of portions or all of the acquired data to constrain the backprojection process. This significantly reduces streak artifacts and increases the overall SNR, permitting decreased numbers of projections to be used when acquiring each image in the image time series. For undersampled 2D projection imaging applications, such as cine phase contrast (PC) angiography, our results suggest that the angular undersampling factor, relative to Nyquist requirements, can be increased from the present factor of 4 to about 100 while increasing SNR per individual time frame. Results are presented for a contrast‐enhanced PR HYPR TRICKS acquisition in a volunteer using an angular undersampling factor of 75 and a TRICKS temporal undersampling factor of 3 for an overall undersampling factor of 225. Magn Reson Med, 2006. © 2005 Wiley‐Liss, Inc.
Nearly optimal three dimensional layout of hypercube networks
Authors: Calamoneri Tiziana , Massini Annalisa
Published: December 2005

In this article we consider the three‐dimensional layout of hypercube networks. Namely, we study the problem of laying hypercube networks out on the three‐dimensional grid with the properties that all nodes are represented as rectangular slices and lie on two opposite sides of the bounding box of the layout volume. We present both a lower bound and a layout method, providing an upper bound on the layout volume and the maximum wire‐length of the hypercube network. © 2005 Wiley Periodicals, Inc. NETWORKS, Vol. 47(1), 1–8 2006
Fault tolerant on‐board networks with priorities
Authors: Bermond J.‐C. , Havet F. , Tóth C.D.
Published: December 2005

We consider on‐board networks in satellites interconnecting entering signals (inputs) to amplifiers (outputs). The connections are made via expensive switches, each of which has four available links. The paths connecting inputs to outputs should be link‐disjoint. Some of the input signals, called priorities, must be connected to the amplifiers that provide the best quality of service (that is, to some specific outputs). In practice, amplifiers are prone to fail, and the faults cannot be repaired. Therefore, extra outputs have to be built into the network to ensure that every input can be routed to operational outputs. Given three integers, n, p, and f, we would like to design a low‐cost network (where the network cost is proportional to the total number of switches) such that it is possible to route all n inputs to n operational amplifiers, and to route the p priorities to the p best quality amplifiers for any set of f faulty and p best‐quality amplifiers. Let R(n, p, f) be the minimum number of switches of such a network. We prove here that
$R(n,p,f)\leq{{n+f}\over{2}}\lceil\log_2p\rceil+{{5}\over{2}}(n-p)+g(f)$
with g a function depending only on f. We then compute R(n, p, f) exactly for a few small values of p and f. © 2005 Wiley Periodicals, Inc. NETWORKS, Vol. 47(1), 9–25 2006
Importance of clinical and epidemiological research in defining the long‐term clinical care of pediatric cancer survivors
Authors: Hawkins Michael M. , Robison Leslie L.
Published: December 2005

With the increasing number of long‐term survivors of childhood cancer, there continues to be a critical need for development and implementation of evidence‐based recommendations for clinical follow‐up. In order to establish and maintain health‐related follow‐up guidelines, it is important to recognize the attributes of research from which the recommendations may be formulated. Issues including study design and clinical research methodology, completeness of long‐term follow‐up for the applicable study population, approaches for assessment of treatment‐related exposures, methods utilized for ascertainment and characterization of outcomes, and recognition of potential modifiers of risk (e.g., demographic or treatment‐specific factors) are all important considerations when evaluating the results of available research. For the future, greater attention will not only need to be given to further development and maintenance of recommendations for follow‐up, but to the scientific evaluation of the recommendations to determine the subsequent impact on health status and quality of life among pediatric cancer survivors. © 2005 Wiley‐Liss, Inc.
Molecular mass characteristics of polyethylene produced with supported vanadium‐magnesium catalysts
Authors: Echevskaya Ludmila G , Matsko Mikhail A , Mikenas Tatiana B , Zakharov Vladimir A
Published: December 2005

Highly active supported vanadium‐magnesium catalysts (VMC) produce polyethylene (PE) with broad and bimodal molecular mass distribution (MMD) in comparison with the famous titanium‐magnesium catalysts (TMC). The effect of hydrogen as an efficient chain‐transfer agent on the MMD of PE has been studied. Increasing hydrogen concentration causes a considerable broadening of MMD of PE due to the shift of the low molecular weight peak on the MMD curve. At the same time, the high molecular weight shoulder stays at the same position even at high hydrogen concentration. This means that VMC contain two types of active centre. One type is very reactive in the chain‐transfer reaction with hydrogen. These centres produce low molecular weight PE in polymerization in the presence of hydrogen. The other type of active centre is not active in chain transfer with hydrogen. These centres produce high molecular weight PE ((1–3) × 106) and hydrogen does not affect the position of the high molecular weight shoulder. MMD data were used to analyze the kinetics of the chain‐transfer reaction with hydrogen and to calculate the rate constants of this reaction. Copyright © 2005 Society of Chemical Industry
Promoting beginning reading success through meaningful assessment of early literacy skills
Authors: Coyne Michael D. , Harn Beth A.
Published: December 2005

Recent scientific advances in early literacy assessment have provided schools with access to critical information about students' foundational beginning reading skills. In this article, we describe how assessment of early literacy skills can help school psychologists promote beginning reading success for all children. First, we identify key skills in early literacy and describe a comprehensive assessment system, Dynamic Indicators of Basic Early Literacy Skills (DIBELS), developed to assess essential beginning reading skills. Next, we present a conceptual framework for thinking about early literacy assessment across four distinct purposes: (a) screening, (b) diagnosis, (c) progress monitoring, and (d) student outcomes. Finally, we provide school‐based examples that illustrate how DIBELS can be used to assess students' early literacy skills across each of these four purposes and facilitate informed and ongoing instructional decision making. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 33–43, 2006.
Curriculum‐based assessment
Authors: Hintze John M. , Christ Theodore J. , Methe Scott A.
Published: December 2005

Curriculum‐based assessment (CBA) measures have become a frequently used assessment tool of school psychologists to assess the academic performance functioning of students in the basic skill areas of reading, mathematics, spelling, and written expression. The purpose of this article is to provide an overview of the different approaches to CBA, with a particular focus on the defining measurement characteristics of each technique. Following this, an illustrative case example is presented that demonstrates how different CBA procedures can be used for (a) making screening and problem‐identification/certification decisions, (b) formulating instructional intervention plans, and (c) monitoring progress toward goal attainment and response to instruction. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 45–56, 2006.
Read together, talk together: The acceptability of teaching parents to use dialogic reading strategies via videotaped instruction
Authors: Blom‐Hoffman Jessica , O'Neil‐Pirozzi Therese M. , Cutting Joanna
Published: December 2005

Dialogic reading (DR) is a set of book‐sharing strategies that caregivers can use with preliterate children. The strategies involve actively engaging young children and encouraging them to verbalize during shared book reading. There is a substantial research base that describes the benefits of using DR strategies with toddlers and preschool‐age children to develop language skills. Recently, a videotaped program, called “Read Together, Talk Together” (RTTT; Pearson Early Learning, 2002) was published. This instructional video teaches adults to use DR strategies with young children. Our research team has begun to examine the acceptability and potential benefits of showing this videotape to caregivers during routine visits to community health centers. The purposes of this brief article are to (a) describe DR strategies and review the DR literature, (b) inform school psychologists about the RTTT video, (c) describe initial pilot data supporting the acceptability of the video to parents and health care staff, and (d) discuss ways school psychologists can incorporate knowledge of DR into their practice. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 71–78, 2006.
Selecting effective academic interventions: An example using brief experimental analysis for oral reading
Authors: Wilber Amy , Cushman Thomas P.
Published: December 2005

The reauthorization of IDEA (the Individuals With Disabilities Education Improvement Act of 2004) includes potential use of a response to intervention (RTI) model for the identification of learning disabilities. Using this model, a variety of academic interventions may be implemented with a low‐achieving student, with the results monitored to determine student response. If this model is to be successfully used, then it is imperative to select and implement relevant interventions. Brief Experimental Analysis (BEA) is a procedure that can be used to assist in the identification and selection of interventions that are likely to be effective for individual students. In this brief article, we review the use and implementation of BEA and provide a case example related to oral reading. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 79–84, 2006.
Beyond grade retention and social promotion: Promoting the social and academic competence of students
Authors: Jimerson Shane R. , Pletcher Sarah M. W. , Graydon Kelly , Schnurr Britton L. , Nickerson Amanda B. , Kundert Deborah K.
Published: December 2005

During the past decade, amidst the current context emphasizing educational standards and accountability, the practice of grade retention has increased. The call for an end to social promotion has generated a variety of recommendations and legislation regarding promotion policies. This context has served as a catalyst for numerous debates regarding the use of grade retention and social promotion. In an era emphasizing evidence‐based interventions, research indicates that neither grade retention nor social promotion is a successful strategy for improving educational success. Moreover, research also reveals prevention and intervention strategies that are likely to promote the social or academic competence of students at risk of poor school performance. It is essential that educational professionals are familiar with the research when implementing interventions to promote student success. School psychologists may use this article as a primer for teachers, administrators, and parents, as it provides a synthesis of research addressing the following important questions: (a) What are the demographic characteristics of retained students? (b) What are the effects of retention on academic and socioemotional outcomes? (c) What long‐term outcomes are associated with grade retention? (d) What are students' perspectives regarding grade retention? (e) How does a developmental perspective enhance our understanding? (f) What are some empirically supported effective intervention strategies? Educational professionals are encouraged to incorporate evidence‐based programs and policies to facilitate the success of all students. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 85–97, 2006.
Kids in the tutor seat: Building schools' capacity to help struggling readers through a cross‐age peer‐tutoring program
Authors: Wright Jim , Cleary Kristi S.
Published: December 2005

Increasingly, elementary schools across America are adopting prereferral intervention models that follow a structured problem‐solving consultation process to reduce referrals to special education and to improve student academic outcomes. One feasible and affordable systems‐level solution for a school that must deliver reading interventions of high quality to many children is an effective cross‐age peer‐tutoring program. The present study examines the impact of a school‐based peer‐tutoring intervention on the fluency of delayed readers in an urban school district. A peer‐tutoring program was implemented across four elementary schools, with a total of 27 tutors and 27 tutees. Tutors and tutees were monitored weekly using CBM oral reading‐fluency probes, and treatment integrity checks were conducted periodically on all tutor pairs. While both tutors and tutees showed increases in reading fluency during the program, students receiving tutoring made substantially greater gains than did tutors. The article provides guidelines for implementing an effective cross‐age peer‐tutoring program in a range of school settings. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 99–107, 2006.
Conducting district‐wide evaluations of special education services: A case example
Authors: Signor‐Buhl Sara J. , LeBlanc Michael , McDougal James
Published: December 2005

In this brief article, a case example is provided that illustrates potential program‐evaluation procedures for examining the outcomes of children served in different models of special education. Specifically, the goal of this project was to evaluate the academic outcomes of children served in self‐contained versus inclusive models of special education programming in a midsize urban school district in Upstate New York. For this evaluation, similar student groupings were formed for analysis by controlling for age, years in placement, significant behavioral problems, and IQ. In this example, reading achievement was significantly higher for students participating in inclusive classrooms on both group and individual measures. No significant difference existed on measures of math achievement. Results indicated that within this school district, students who were educated in inclusive settings achieved at a rate that is comparable to or better than those educated in self‐contained settings. Implications for other districts interested in engaging in similar program evaluations are discussed. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 109–115, 2006.
Inflammatory protein profile during systemic high dose interleukin‐2 administration
Authors: Rossi Leonardo , Martin Brian M. , Hortin Glen L. , White Richard L. , Foster Mareva , Moharram Ramy , Stroncek David , Wang Ena , Marincola Francesco M. , Panelli Monica C.
Published: December 2005

Systemic interleukin‐2 (IL‐2) administration induces an assortment of downstream effects whose biological and therapeutic significance remains unexplored mostly because of the methodological inability to globally address their complexity. Protein array analysis of sera from patients with renal cell carcinoma obtained prior and during high‐dose IL‐2 therapy had previously revealed extensive alterations in expression of the soluble factors analyzed, whose discovery was limited by the number of capture antibodies selected for protein detection. Here, we expanded the analysis to SELDI‐TOF‐MS and quantitative protein analysis (nephelometry). All cytokines/chemokines detected by protein arrays were below the SELDI detection limit, while novel IL‐2‐specific changes in expression of acute‐phase reactants and high‐density lipoprotein metabolites could be identified. Serum amyloid protein A (SAA) and C‐reactive protein expression were consistently up‐regulated after four doses of IL‐2, while other proteins were down‐regulated. These findings were confirmed by SELDI immunoaffinity capture and nephelometry. Immunoaffinity capture revealed different, otherwise undetectable, isoforms of SAA. A linear correlation between peak area by SELDI and protein concentration by nephelometry was observed. Overall distinct yet complementary information was obtained using different platforms, which may better illustrate complex phenomena such as the systemic response to biological response modifiers.
Light gauge construction
Authors: Hancock G J
Published: December 2005

The most significant developments in the design of light gauge cold‐formed steel structural members in 1996 have been the publication of the new edition of the American Iron and Steel Institute Specification for cold‐formed steel structural members, the publication of the CEN document Eurocode 3, Part 1.3 for cold‐formed thin‐gauge members and sheeting, and the publication of the limit states Australian/New Zealand Standard AS 4600:1996 for cold‐formed steel structures. All three codes of practice are based on the most recently available research. This review also summarizes research published in 1995/1996 which is aimed at further improvements in design.
Seismic performance of RC bridges
Authors: Calvi G Michele
Published: December 2005

This review presents the most recent trends in bridge design, assessment and retrofitting. An appraisal of the damage caused by recent earthquakes and the typical problems encountered introduces a discussion of the current status of research: consideration of seismic input and interaction with the soil, including liquefaction of soil, recent code provisions and some proposals emerging from recent research in relation to design concepts and philosophy, and methods of analysis. Assessment and strengthening of existing bridges, including artificial isolation, are also reviewed.
Seismic analysis of RC structures
Authors: Fardis Michael N
Published: December 2005

This review summarizes the current state‐of‐the‐art and practice of linear elastic seismic analysis of RC structures for codified seismic design and of nonlinear analysis for research purposes. For elastic analysis, the concepts and mechanics of modal dynamic analysis are described, with emphasis on the multimodal response spectrum method and on the combination of modal responses for one‐dimensional or multidimensional internal forces. The two most common nonlinear dynamic solution schemes are described and member‐type hysteretic models are reviewed in detail, with emphasis on the general 3D Fibre models and on simple 1D models, of the distributed and lumped inelasticity types.
Composite slabs
Authors: Wright Howard D
Published: December 2005

Composite slabs are now one of the most popular methods of steel frame floor construction in the world. This article describes the history of their development with special reference to the research undertaken to predict their behaviour. The essential nature of the system is that the profiled steel sheeting acts as both a form and reinforcement to the final concrete slab. The use of the sheeting as a form is similar to its use in roofing and cladding when wind and snow are the predominant loads; however, there are sufficient differences to make the design of composite deck profiles unique. The exact nature of the bond between concrete and steel is, in the author's opinion, still not well understood and is the subject of much international research activity. However, it will be concluded that the continuing effort in research in this area is of little practical benefit to improving deck spans as in most situations the slab end support conditions are such as to allow fully composite behaviour.
Safety assessment of structures in nuclear facilities: application of probabilistic methods
Authors: Ellingwood Bruce R
Published: December 2005

Probabilistic methods are being used increasingly to provide a framework for rational analysis of uncertainty and to manage risk to engineered facilities from rare events. Facility design, management and regulation must have a wellestablished rationale in today's increasingly litigious society. Nowhere is this more apparent than in the nuclear industry, where probabilistic methods have been applied to improve structural engineering practice in several areas: design of new structures, condition assessment of existing facilities, and probabilistic risk assessment.

This review will provide the reader with an idea of the utility of structural reliability methods in the nuclear industry, and will identify some of the challenges that remain as barriers to the use of probabilistic concepts in facility risk management and regulation.