bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of various crosslinking systems on the mechanical properties of gas phase EPDM/PP thermoplastic vulcanizates
Authors: Maiti Madhuchhanda , Patel Jaydeep , Naskar Kinsuk , Bhowmick Anil K.
Published: September 2006

Dynamically cured thermoplastic elastomers or thermoplastic vulcanizates (TPVs) are widely used nowadays for their unique characteristics. In this paper, gas phase ethylene–propylene–diene terpolymer (GEPDM)/Polypropylene (PP) TPVs with various crosslinking systems have been extensively studied to optimize the curative level in each crosslinking system with special reference to their mechanical properties. Optimized systems were compared for heat aging, recyclability, crosslink density, morphology studies, and dynamic mechanical analysis. Crosslinking by peroxide in the presence of triallyl cyanurate as a coagent gives best overall performance with reference to excellent heat aging behavior, tension set, and compatibility between GEPDM and PP. Conventional EPDM/PP system was also compared with GEPDM/PP system. GEPDM/PP system was found to exhibit better behavior in all respects. Significant correlations were obtained between delta torque values obtained from Moving Die Rheometer and modulus or cross link density of TPVs irrespective of the nature of crosslinking agent. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5463–5471, 2006
Synergistic effect of supported nickel catalyst with intumescent flame‐retardants on flame retardancy and thermal stability of polypropylene
Authors: Song Rongjun , Zhang Baoyan , Huang Baotong , Tang Tao
Published: September 2006

Supported nickel catalyst (Ni‐Cat) was used as a catalyst to improve the flame retardancy of intumescent flame‐retardants (IFR) systems based on ammonium polyphosphate and pentaerythritol (PETOL) in polypropylene (PP) matrix. Limited oxygen index (LOI), UL‐94 rating, and thermogravimetric analysis were used to characterize the flame retardancy and thermal stability of the PP systems, and field emission scanning electron microscopy (FE‐SEM) and Fourier transformed infrared spectroscopy (FTIR) were used to analyze the microstructure and composition of the chars formed during measuring LOI value and after combustion at 800°C. The catalytic effect of Ni‐Cat was shown in an increase of LOI, a change in the char microstructure, and improvement of the thermal stability in the PP systems, which result from the synergistic effect of Ni‐Cat and IFR. The results from FE‐SEM and FTIR spectra of the char can explain how this synergistic effect happened. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5988–5993, 2006
Influence of leather stretching to gain area yield on its stress‐relaxation behavior
Authors: Manich A. M. , de Castellar M. D. , González Berania , Ussman M. H. , Marsal A.
Published: September 2006

Four bovine leathers subjected to five stretching procedures in water at different temperatures between 60 and 80°C and drawing ratios between 1.20 and 1.40 were analyzed to demonstrate the suitability of the generalized Maxwell model to fit the different stress‐relaxation processes related to the structural hierarchy of leather. This consists of a set of three Maxwell units connected in parallel to represent the high‐rate, the medium‐rate, and the low‐rate stress‐relaxation processes, and a Hookean spring in parallel to represent the residual stress at the equilibrium. The high‐rate, the medium‐rate and the low‐rate relaxation times were approximately of 0.6, 10, and 200 s, respectively. Stretching of leather under different conditions to gain area yield in addition to a reduction in thickness also produces a decrease in leather density but not always induce hardening of leather. Leather stretching increases the initial stress when leather is strained 20% for stress‐relaxation tests. The effect of stretching on the residual stress depends on the level of stretching. The hardening effect of stretching measured by relative softness showed a good relationship with the medium‐rate relaxed stress. The harder the stretched leather the higher the decrease in the medium‐rate relaxed stress. Softness also showed a good relationship with the low‐rate relaxation time. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6000–6008, 2006
Processing and property improvement of polymeric composites with added ZnO nanoparticles through microinjection molding
Authors: Huang C. K. , Chen S. W. , Wei W. C. J.
Published: September 2006

The use of nanoparticulates in polymeric materials has become a potential alternative for organic–inorganic composite materials because of their versatility in property modification and ease of batch fabrication. This paper investigates the kneading and mechanical properties of polypropylene (PP) with added nano‐ZnO powder in sizes of 10–30 nm, through batch kneading and microinjection molding processes. The results show that the PP microgears with added ZnO nanoparticles are well replicated with clear structural definition. The resulting composites with a small amount of nanofiller added exhibit significant improvement in wear resistance and mechanical properties. The possible strengthening and wearing mechanisms is discussed based on the investigation of the worn and fractured surfaces of the composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6009–6016, 2006
Submicrometer characterization of surfaces of epoxy‐based organic–inorganic nanocomposite coatings. A comparison of AFM study with currently used testing techniques
Authors: Špírková Milena , Šlouf Miroslav , Bláhová Olga , Farkačová Tereza , Benešová Jaroslava
Published: September 2006

Surface properties (morphology, hardness) of transparent colorless epoxy‐based organic–inorganic nanocomposite coatings were investigated by atomic force microscopy, optical and scanning electron microscopy, nanoindentation, and the Persoz pendulum test. Friction and wear coefficients were obtained from tribological experiments. The influence of mechanical properties and the size, shape, and concentration of additives (colloidal silica particles and montmorillonite sheets) on the measured surface characteristics are discussed. It was found that the highest surface hardness (assigned by nanoindentation, pendulum test or expressed as the scratch resistance) exhibited materials with the glass‐transition temperature close to 20°C. Microcopy techniques revealed that surface morphology is influenced by both types of admixtures: on the nanometer scale by colloidal silica particles and on micrometer scale by montmorillonite platelets. Already 1 wt % of montmorillonite increased friction coefficients and wear resistance without distinctive changes of tensile properties. However, the addition of ˜ 20 wt. % of silica nanoparticles was necessary for the increase of wear and scratch resistances. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5763–5774, 2006
Synthesis of Some New Quinoxalines and 1,2,4‐Triazolo[4,3‐a]‐quinoxalines for Evaluation of in vitro Antitumor and Antimicrobial Activities
Authors: El‐Hawash Soad A. M. , Habib Nargues S. , Kassem Mervat A.
Published: September 2006

Two novel series of quinoxalines derived from 3‐phenylquinoxalin‐2(1H)‐one and 2‐hydrazino‐3‐phenylquinoxaline, namely 1‐substituted‐3‐phenylquinoxaline‐2(1H)‐ones, 2a–c, 3a–d, and 4; 2‐(3‐oxo‐3,3a,4,5,6,7‐hexahydroindazol‐2‐yl)‐3‐phenylquinoxaline 6; N‐ cyclopentylidene or benzylidene‐N′‐(3‐phenylquinoxaline‐2‐yl)hydrazines, 7 and 18; 1‐substituted‐4‐phenyl‐1,2,4‐triazolo[4,3‐a]quinoxalines, 9, 10, 12, 13, 14, and 16 have been synthesized in order to evaluate their antitumor and antimicrobial activities. Preliminary screening at NCI showed that compounds 2b, 2c, 3b, 3c, and 9 exhibited a moderate to strong growth inhibition activity on various tumor panel cell lines between 10–6 to 10–5 molar concentrations. Compound 3b was the most active with a broad spectrum of activity. Compound 3c showed selectivity towards CNS‐cancer SF‐639, leukemia CCRF‐CEM, and melanoma SK‐MEL‐5 (GI50 = 4.03, 6.46, and 4.17 μM, respectively). On the other hand, the in vitro microbiological data revealed that the prepared compounds showed mild antimicrobial activity.
Role of aggrecanase 1 in Lyme arthritis
Authors: Behera Aruna K. , Hildebrand Ethan , Szafranski Jon , Hung Han‐Hwa , Grodzinsky Alan J. , Lafyatis Robert , Koch Alisa E. , Kalish Robert , Perides George , Steere Allen C. , Hu Linden T.
Published: September 2006

Objective

Arthritis is one of the hallmarks of late‐stage Lyme disease. Previous studies have shown that infection with Borrelia burgdorferi, the causative agent of Lyme disease, results in degradation of proteoglycans and collagen in cartilage. B burgdorferi do not appear to produce any exported proteases capable of digesting proteoglycans and collagen, but instead, induce and activate host proteases, such as matrix metalloproteinases (MMPs), which results in cartilage degradation. The role of aggrecanases in Lyme arthritis has not yet been determined. We therefore sought to delineate the contribution of aggrecanases to joint destruction in Lyme arthritis.

Methods

We examined the expression patterns of aggrecanases 1 and 2 (ADAMTS 4 and 5, respectively) in B burgdorferi–infected primary human chondrocyte cell cultures, in synovial fluid samples from patients with active Lyme arthritis, and in the joints of mice by real‐time quantitative reverse transcription–polymerase chain reaction and immunoblotting techniques. Bovine cartilage explants were used to determine the role of aggrecanases in B burgdorferi–induced cartilage degradation.

Results

ADAMTS‐4, but not ADAMTS‐5, was induced in human chondrocytes infected with B burgdorferi. The active forms of ADAMTS‐4 were increased in synovial fluid samples from patients with active Lyme arthritis and were elevated in the joints of mice infected with B burgdorferi. Using cartilage explant models of Lyme arthritis, it appeared that the cleavage of aggrecan was predominantly mediated by “aggrecanases” rather than MMPs.

Conclusion

The induction of ADAMTS‐4 by B burgdorferi results in the cleavage of aggrecan, which may be an important first step that leads to permanent degradation of cartilage.
The role of fibroblasts and fibroblast‐derived factors in periprosthetic osteolysis
Authors: Koreny Tamas , Tunyogi‐Csapó Miklós , Gál Istvan , Vermes Csaba , Jacobs Joshua J. , Glant Tibor T.
Published: September 2006

Objective

This study was undertaken to investigate how fibroblasts respond to stimulation with particulate wear debris and/or conditioned media obtained from pathologic tissue, and whether these activated fibroblasts express compounds that are involved in bone resorption.

Methods

Conditioned media from explant cultures of synovial tissue, periprosthetic soft tissue (interface membranes), titanium particles, and proinflammatory cytokines were used to stimulate fibroblasts. RNase protection assay was used to measure altered gene expression, and enzyme‐linked immunosorbent assay, Western blot hybridization, and flow cytometry were used to determine fibroblast protein expression. Tartrate‐resistant acid phosphatase staining was used to identify multinucleated osteoclast‐like cells.

Results

The most dominant compounds measured in the conditioned media from interface membranes were tumor necrosis factor α (TNFα), monocyte chemoattractant protein 1 (MCP‐1), interleukin‐1β (IL‐1β), IL‐6, IL‐8, and vascular endothelial growth factor. Fibroblasts phagocytosed particulate wear debris and responded to cytokine/chemokine stimulation. The most prominent up‐regulated genes and proteins secreted by fibroblasts in response to stimulation were matrix metalloproteinase 1, MCP‐1, IL‐1β, IL‐6, IL‐8, cyclooxygenase 1 (COX‐1), COX‐2, leukemia inhibitory factor 1, transforming growth factor β1 (TGFβ1), and TGFβ receptor type I. In addition, interface membrane fibroblasts expressed RANKL and osteoprotegerin in response to stimulation with conditioned media, TNFα, or IL‐1β. Stimulated fibroblasts cocultured with bone marrow cells in the presence of macrophage colony‐stimulating factor induced osteoclastogenesis.

Conclusion

Interface membrane fibroblasts respond directly to particulate wear debris, possibly via phagocytosis, expressing proinflammatory cytokines and RANKL. Thus, these cells may be actively involved in osteoclastogenesis and pathologic (periprosthetic) bone resorption.
Transglutaminase 2 limits murine peritoneal acute gout‐like inflammation by regulating macrophage clearance of apoptotic neutrophils
Authors: Rose David M. , Sydlaske Anya D. , Agha‐Babakhani Amir , Johnson Kristen , Terkeltaub Robert
Published: September 2006

Objective

Monosodium urate monohydrate (MSU) crystals have remarkable inflammatory potential. However, gouty inflammation is spontaneously self‐limited, an occurrence recognized since antiquity. Gouty synovitis is driven and sustained by neutrophil influx. Importantly, macrophage phagocytosis of apoptotic (but not necrotic) neutrophils is antiinflammatory. Therefore, we tested the hypothesis that efficient clearance of apoptotic neutrophils by macrophages is one of the factors that restrains the progression of gouty inflammation. Macrophage expression of transglutaminase 2 (TG2), a multifunctional protein with reciprocally regulated transamidation and purine nucleotide–binding activities, promotes apoptotic leukocyte uptake. In this study, we tested the specific role of macrophage TG2 expression in MSU crystal–induced inflammation.

Methods

We studied MSU crystal–induced peritonitis in TG2−/− and congenic TG2+/+ mice. We also studied the effects of TG2 on apoptotic cell uptake by cultured macrophages.

Results

TG2−/− mice demonstrated more progressive neutrophilic accumulation than did TG2+/+ mice, which was associated with delayed clearance of apoptotic neutrophils during MSU crystal–induced peritonitis. We observed defective phagocytosis of apoptotic leukocytes by TG2−/− peritoneal macrophages, which was corrected by soluble extracellular TG2. Transamidation catalytic activity of TG2 was not required to mediate macrophage uptake of apoptotic leukocytes. In contrast, the TG2 nucleotide binding site residue K173 was critical for this TG2 function. TG2 bound to GDP, ADP, or ATP (but not to GTP) rescued defective apoptotic leukocyte uptake by TG2−/− macrophages.

Conclusion

Enhancement of apoptotic neutrophil uptake by macrophage‐derived TG2 restrains gout‐like neutrophilic peritoneal inflammation. Differential binding of TG2 by purine nucleotides may contribute to clinical variability in the extent and duration of gouty inflammation.
Treatment of giant cell arteritis using induction therapy with high‐dose glucocorticoids: A double‐blind, placebo‐controlled, randomized prospective clinical trial
Authors: Mazlumzadeh Mehrdad , Hunder Gene G. , Easley Kirk A. , Calamia Kenneth T. , Matteson Eric L. , Griffing W. Leroy , Younge Brian R. , Weyand Cornelia M. , Goronzy Jörg J.
Published: September 2006

Objective

Glucocorticoid (GC) therapy for giant cell arteritis (GCA) is effective but requires prolonged administration, resulting in adverse side effects. The goal of the current study was to test the hypothesis that induction treatment with high‐dose pulse intravenous (IV) methylprednisolone permits a shorter course of therapy.

Methods

Twenty‐seven patients with biopsy‐proven GCA were enrolled in a randomized, double‐blind, placebo‐controlled study to receive IV methylprednisolone (15 mg/kg of ideal body weight/day) or IV saline for 3 consecutive days. All patients were started on 40 mg/day prednisone and followed the same tapering schedule as long as disease activity was controlled. The numbers of patients with disease in remission after 36, 52, and 78 weeks of treatment and taking ≤5 mg/day prednisone were compared. Cumulative prednisone dose, number of relapses, and development of adverse GC effects were assessed.

Results

Ten of the 14 IV GC–treated patients, but only 2 of 13 control patients, were taking ≤5 mg/day prednisone at 36 weeks (P = 0.003). This difference was maintained; there was a higher number of sustained remissions after discontinuation of treatment in the IV GC–treated group and a lower median daily dose of prednisone at 78 weeks (P = 0.0004). The median cumulative dose of oral prednisone, excluding the IV GC dose, was 5,636 mg in the IV GC–treated group compared with 7,860 mg in the IV saline–treated group (P = 0.001).

Conclusion

Initial treatment of GCA with IV GC pulses allowed for more rapid tapering of oral GCs and had long‐term benefits, with a higher frequency of patients experiencing sustained remission of their disease after discontinuation of treatment.
Aggregation of opinions based on correlated cues and advisors
Authors: Budescu David V. , Yu Hsiu‐Ting
Published: September 2006

We study the process by which decision makers (DMs) aggregate probabilistic opinions from multiple, correlated sources with a special emphasis on the determinants of the DM's confidence, which is a predictor of the DM's willingness to accept the implications of the aggregation process. Our model assumes that (a) DM combines the advisors' opinions by weighting them according to the amount of information underlying them, and (b) the DM's confidence increases as a function of a variety of factors that reduce the variance of the aggregate. We report results of three studies that manipulate the predictive validity of the cues and their inter‐correlations. Most of the models' predictions are supported but, contrary to the model's prediction, the DMs' confidence is not sensitive to the inter‐cue correlation. The best predictors of the DMs' confidence are the perceived predictability of the event, the level of agreement among the advisors, and the advisors' self‐reports of confidence. This pattern of results is explained by the ‘system neglect’ hypothesis. Copyright © 2006 John Wiley & Sons, Ltd.
Holoprosencephaly: Clinical, anatomic, and molecular dimensions
Authors: Cohen M. Michael
Published: September 2006

Holoprosencephaly is addressed under the following headings: alobar, semilobar, and lobar holoprosencephaly; arrhinencephaly; agenesis of the corpus callosum; pituitary abnormalities; hindbrain abnormalities; syntelencephaly; aprosencephaly/atelencephaly; neural tube defects; facial anomalies; median cleft lip; minor facial anomalies; single maxillary central incisor; holoprosencephaly‐like phenotype; epidemiology; genetic causes of holoprosencephaly; teratogenic causes of holoprosencephaly; SHH mutations; ZIC2 mutations; SIX3 mutations; TGIF mutations; PTCH mutations; GLI2 mutations; FAST1 mutations; TDGF1 mutations; and DHCR7 mutations. Birth Defects Research (Part A) 76:658–673, 2006. © 2006 Wiley‐Liss, Inc.
Molecular analysis of successful cell line selection in transfected GS‐NS0 myeloma cells
Authors: Barnes Louise M. , Bentley Catherine M. , Moy Nicola , Dickson Alan J.
Published: September 2006

The production of recombinant proteins from mammalian cells is now an essential part of biotechnology. However, despite this importance, the detailed characteristics of good producing cell lines remain largely unknown. The industrially important GS‐NS0 mammalian expression system is able to produce large amounts of protein from relatively few copies of recombinant genes. This makes GS‐NS0 cell lines ideal candidates to study the consequence of recombinant plasmid transfection in mammalian cells. This study investigated the molecular features of a panel of 17 randomly chosen GS‐NS0 cell lines engineered to produce a recombinant antibody. The research analysed antibody production via enzyme‐linked immunosorbent assay (ELISA), and investigated the molecular features of the transfectants by Northern, Southern and copy number analysis. The cell lines generated produced a range of antibody concentrations. In addition, for transfectants defined as producers of recombinant antibody there was a positive correlation between specific productivity and heavy chain mRNA expression. The use of Northern and Southern analysis allowed determination of the functional integrity of the transfected plasmid. Over 50% of the transfectants studied had molecular defects at the level of mRNA and/or cDNA. Cell lines were identified with suspected defects in the regulatory regions of transfected genes in addition to cell lines which lacked recombinant genes. Also, “false‐positive” cell lines were generated which were able to overcome the GS selection pressure without producing any recombinant antibody. This article discusses these findings in relation to vector design. Biotechnol. Bioeng. 2007;96: 337–348. © 2006 Wiley Periodicals, Inc.
Culture media optimization for growth and phycoerythrin production from Porphyridium purpureum
Authors: Kathiresan S. , Sarada R. , Bhattacharya Sila , Ravishankar G.A.
Published: September 2006

Porphyridium spp. is a red micro alga and is gaining importance as a source of valuable products viz., phycobiliproteins (PB), sulfated exopolysaccharides, and polyunsaturated fatty acids with potential applications in the food and pharmaceutical industries. In the present study, the effects of the major media constituents of Porphyridium species were studied using response surface methodology (RSM) on biomass yield, total PB and the production of phycoerythrin (PE). A second order polynomial can be used to predict the PB and PE production in terms of the independent variables. The independent variables such as the concentrations of sodium chloride, magnesium sulfate, sodium nitrate, and dipotassium hydrogen phosphate influenced the total PB and PE production. The optimum conditions showed that total PB was 4.8% at the concentration of sodium chloride 26.1 g/L, magnesium sulfate 5.23 g/L, sodium nitrate 1.56 g/L, and dipotassium hydrogen phosphate 0.034 g/L. In case of optimum PE production (3.3%), the corresponding values are 29.62, 6.11, 1.59, and 0.076 g/L, respectively. PE production depends greatly on the concentrations of chloride, nitrate, and sulfate as well as phosphate of which the former possess the maximum effect. Biotechnol. Bioeng. 2007;96: 456–463. © 2006 Wiley Periodicals, Inc.
Using CCSSE in planning for quality enhancement
Authors: Balog Scott E. , Search Sally P.
Published: September 2006

This chapter describes how Tallahassee Community College used CCSSE data as part of its overall student‐retention program, consisting of faculty workshops, analysis of state accountability data, and conscious incorporation of best practices. The resulting Quality Enhancement Plan (QEP) meets accreditation requirements and strengthens the college's strategic plan.
Limitations of community college benchmarking and benchmarks
Authors: Bers Trudy H.
Published: September 2006

This chapter distinguishes between benchmarks and benchmarking, describes a number of data and cultural limitations to benchmarking projects, and suggests that external demands for accountability are the dominant reason for growing interest in benchmarking among community colleges.
Key resources on benchmarking in community colleges
Authors: Sheldon Caroline Q. , Durdella Nathan R.
Published: September 2006

This chapter reviews resources from scholars, practi‐tioners, and policymakers on benchmarking in community colleges.
Representative process sampling for reliable data analysis—a tutorial
Authors: Petersen Lars , Esbensen Kim H.
Published: September 2006

Process sampling of moving streams of particulate matter, fluids and slurries (over time or space) or stationary one‐dimensional (1‐D) lots is often carried out according to existing tradition or protocol not taking the theory of sampling (TOS) into account. In many situations, sampling errors (sampling variances) can be reduced greatly however, and sampling biases can be eliminated completely, by respecting a simple set of rules and guidelines provided by TOS. A systematic approach for description of process heterogeneity furnishes in‐depth knowledge about the specific variability of any 1‐D lot. The variogram and its derived auxiliary functions together with a set of error generating functions provide critical information on:—process variation over time or space,—the number of extracted increments to composite into a final, optimal sample,—the frequency with which to extract increments—and which sampling scheme will be optimal (random, stratified random or systematic selection). In addition variography will delineate cyclic behaviors as well as long‐term trends thereby ensuring that future sampling will not accidentally be performed with a sampling rate coincident with the frequency of any hidden cycle, eliminating the risk of underestimating process variation. A brief description of selected hardware for extraction of samples from 1‐D lots is provided in order to illustrate the key issues to consider when installing new, or optimizing existing sampling devices and procedures. A number of practical examples illustrate the use of TOS and variography to design optimal sampling protocols for a variety of typical process situations. Copyright © 2006 John Wiley & Sons, Ltd.
Characterization and prediction of solute properties in methanol–water association by chemometrics analysis of solvation data
Authors: Hemmateenejad Bahram
Published: September 2006

Methanol–water binary mixtures have been characterized as a ternary or quaternary system composed of unassociated methanol (M) and water (W) and one or two methanol–water complex (MW). Identification of the methanol–water association was performed by chemometrics analysis of some solvent‐related properties of binary methanol–water mixtures with compositions between 0 and 100% volume percent of methanol. Abstract factor analysis of the solvation data identified three chemical species in the solvent mixtures that can be attributed to the pure methanol and water solvents and a MW association. The stoichiometric molar ratio of the W:M associate was investigated by the multivariate curve resolution‐alternative least squares (MCR‐ALS) of the solvation data and the resulted concentration profiles of the solvent species implied a 1:1 molar ratio for the M:W association. The equilibrium constant of the formation of the M–W association was determined by MCR‐ALS and iterative rank annihilation factor analysis (RAFA) to be equal to 13.72. The solvation data of the pure M–W cluster was calculated by target factor analysis (TFA) procedure. Higher hydrogen‐bond basicity and lower hydrogen‐bond acidity was obtained for the MW solvent in comparison with both the M and W solvents. The proposed model was employed to calculate the acidity constant and HPLC capacity factors of some solutes in the MW cluster. Interestingly, the solutes were found to be stronger acid in relative to pure methanol and water. Finally, the specific solute–solvent interactions and preferential solvation of the solutes were explained by the non‐modeled solute‐related data. Copyright © 2006 John Wiley & Sons, Ltd.
The control of microtubule stability in vitro and in transfected cells by MAP1B and SCG10
Authors: Bondallaz Percy , Barbier Anne , Soehrman Sophia , Grenningloh Gabriele , Riederer Beat M.
Published: September 2006

In neurons, the regulation of microtubules plays an important role for neurite outgrowth, axonal elongation, and growth cone steering. SCG10 family proteins are the only known neuronal proteins that have a strong destabilizing effect, are highly enriched in growth cones and are thought to play an important role during axonal elongation. MAP1B, a microtubule‐stabilizing protein, is found in growth cones as well, therefore it was important to test their effect on microtubules in the presence of both proteins. We used recombinant proteins in microtubule assembly assays and in transfected COS‐7 cells to analyze their combined effects in vitro and in living cells, respectively. Individually, both proteins showed their expected activities in microtubule stabilization and destruction respectively. In MAP1B/SCG10 double‐transfected cells, MAP1B could not protect microtubules from SCG10‐induced disassembly in most cells, in particular not in cells that contained high levels of SCG10. This suggests that SCG10 is more potent to destabilize microtubules than MAP1B to rescue them. In microtubule assembly assays, MAP1B promoted microtubule formation at a ratio of 1 MAP1B per 70 tubulin dimers while a ratio of 1 SCG10 per two tubulin dimers was needed to destroy microtubules. In addition to its known binding to tubulin dimers, SCG10 binds also to purified microtubules in growth cones of dorsal root ganglion neurons in culture. In conclusion, neuronal microtubules are regulated by antagonistic effects of MAP1B and SCG10 and a fine tuning of the balance of these proteins may be critical for the regulation of microtubule dynamics in growth cones. Cell Motil. Cytoskeleton 2006. © 2006 Wiley‐Liss, Inc.
Significant regional variation in adequacy of lymph node assessment and survival in gastric cancer
Authors: Coburn Natalie G. , Swallow Carol J. , Kiss Alex , Law Calvin
Published: September 2006

BACKGROUND

Lymph node (LN) status is a major determinant of prognosis and treatment of gastric adenocarcinoma. The 1997 American Joint Commission on Cancer/Union Internationale Contre le Cancer guidelines were revised, requiring examination of ≥15 LN for staging.

METHODS

We investigated compliance with these guidelines and the correlation with overall survival (OS) by analyzing 10,807 resected gastric cancers in the Surveillance, Epidemiology and End Results (SEER) database, 1988–2002. Kaplan–Meier survival curves were constructed; survival was compared by using Cox proportional hazards.

RESULTS

Overall, 29% of cases had ≥15 LN examined. After 1997, the median number of LN assessed increased from 9 to 10 (P < .0001). Factors predictive of adequate LN assessment (ALNA) were higher stage, worse grade, age <74 years, later year of diagnosis, nonwhite race, more extensive surgery, female sex, and SEER region. Differences in the rate of ALNA between regions were noted, ranging from 19.7–53% (P < .0001). Of T1N0 patients, 19% had ALNA. Improved OS was predicted by earlier stage, lower grade, marital status, Asian race, younger age, T‐stage, female sex, SEER region, and ALNA. Median OS was highest in the region with the best ALNA rate and worst in the region with the lowest (33 mos vs. 17 mos, P < .0001). Inadequate LN assessment led to poorer survival at every stage (P < .001).

CONCLUSION

The overwhelming majority of patients have an inadequate LN assessment. ALNA was associated with improved OS, with significant variation across regions. Understaging due to inadequate LN assessment may affect eligibility for adjuvant therapy. Education is required to improve LN retrieval. Cancer 2006. © 2006 American Cancer Society.
Multiple states based temporal consistency for dynamic verification of fixed‐time constraints in Grid workflow systems
Authors: Chen Jinjun , Yang Yun
Published: September 2006

To verify fixed‐time constraints in Grid workflow systems, consistency and inconsistency conditions have been defined in conventional verification work. However, with a view of the run‐time uncertainty of activity completion duration, we argue that, although the conventional consistency condition is feasible, the conventional inconsistency condition is too restrictive and covers several different states. These states, which are handled conventionally by the same exception handling, should be handled differently for the purpose of cost saving. Therefore, in this paper, we divide conventional inconsistency into weak consistency, weak inconsistency and strong inconsistency and treat conventional consistency as strong consistency. Correspondingly, we develop some algorithms on how to verify them. Based on this, for weak consistency we present a method on how to adjust it to strong consistency by using mean activity time redundancy and temporal dependency between fixed‐time constraints. For weak inconsistency, we analyse briefly why it can be handled by simpler and more cost‐saving exception handling while for strong inconsistency, the conventional exception handling remains deployed. The final quantitative evaluation demonstrates that our research can achieve better cost‐effectiveness than the conventional work. Copyright © 2006 John Wiley & Sons, Ltd.
Diastereopure Cationic NCN‐Pincer Palladium Complexes with Square Planar η4‐N,C,N,O Coordination
Authors: Gosiewska Silvia , Herreras Martinez Sara , Lutz Martin , Spek Anthony L. , van Koten Gerard , Klein Gebbink Robertus J. M.
Published: September 2006

Neutral NCN‐pincer palladium bromide complex 2 containing the monoanionic, enantiopure pincer ligand 2,6‐bis{[(S)‐2‐hydroxymethyl‐1‐pyrrolidinyl]methyl}phenyl bromide (1) with bis‐ortho‐(S)‐prolinol substituents was synthesized and isolated as a mixture of three stereoisomers [(SN,SN,SC,SC), (RN,SN,SC,SC), and (RN,RN,SC,SC)] in a 1:1:1 ratio. Upon abstraction of the bromide ion from the unresolved mixture of 2, single diastereoisomers of the cationic complexes [3]BF4 and [3]PF6, respectively, were formed with a uniqueη4‐N,C,N,O coordination mode of ligand 1. X‐ray crystal structure determination established the intramolecularη4‐N,C,N,O coordination of 1 to palladium where the typical mer‐η3‐N,C,N pincer coordination is accompanied by coordination of one of the hydroxy groups of the (S)‐prolinol moieties. The water molecule that was cocrystallized in the crystal structure of [3]PF6 does not coordinate to palladium, but instead is involved in a hydrogen bonding network. The catalytic potential of both cationic complexes, [3]BF4 and [3]PF6, was tested in an aldol reaction of aldehydes with methyl isocyanoacetate to yield the oxazoline products as racemic mixtures.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A novel type of deletion in the CDKN2A gene identified in a melanoma‐prone family
Authors: Knappskog Stian , Geisler Jürgen , Arnesen Thomas , Lillehaug Johan R. , Lønning Per E.
Published: September 2006

Linkage to the CDKN2A locus has been demonstrated in ∼50% of families with hereditary malignant melanoma but only a subgroup of these harbor identified mutations. We here report a Norwegian melanoma‐prone family with a novel large germline deletion removing 13707 bps of the CDKN2A gene, including exon 1α and approximately half of exon 2. Our finding is the first reported large CDKN2A germline deletion with a breakpoint located within an exon. This type of deletion is not detectable through the direct exon sequencing and may also escape identification by use of multiplex ligation‐dependent probe amplification (MLPA) analysis. Here, the defect was identified through detection of a truncated p14(ARF) mRNA and loss of p16(INK4a) mRNA expression from the affected allele. Our finding suggests that atypical, large deletions in the CDKN2A gene may explain linkage to the 9p21 chromosome band without identified gene mutations among melanoma‐prone families. Thus, it illustrates the need to include p14(ARF)‐ and p16(INK4a) transcript analysis when searching for unknown mutations within the CDKN2A locus in melanoma‐prone families. Similar deletions with atypical breakpoints may affect other genes involved in cancer disposition, and the need to examine gene transcripts in high‐risk families with no mutation identified through conventional testing should be considered. © 2006 Wiley‐Liss, Inc.
BMP and LIF signaling coordinately regulate lineage restriction of radial glia in the developing forebrain
Authors: Li Hedong , Grumet Martin
Published: September 2006

The earliest radial glia are neural stem cells that guide neural cell migration away from ventricular zones. Subsequently, radial glia become lineage restricted during development before they differentiate into more mature cell types in the CNS. We have previously shown that subpopulations of radial glial cells express markers for glial and neuronal restricted precursors (GRPs and NRPs) in expression patterns that are temporally and spatially regulated during CNS development. To characterize further the mechanism of this regulation in rat forebrain, we tested whether secreted factors that are present during development effect lineage restriction of radial glia. We show here that in radial glial cultures LIF/CNTF up‐regulates, whereas BMP2 down‐regulates GRP antigens recognized by monoclonal antibodies A2B5/4D4. These activities combined with secretion of BMPs dorsally and LIF/CNTF from the choroid plexus provide an explanation for the graded distribution pattern of A2B5/4D4 in dorso‐lateral ventricular regions in vivo. The regulation by LIF/CNTF of A2B5/4D4 is mediated through the JAK‐STAT pathway. BMP2 promotes expression on radial glial cells of the NRP marker polysialic acid most likely by regulating N‐CAM expression itself, as well as at least one polysialyl transferase responsible for synthesis of polysialic acid on N‐CAM. Taken together, these results suggest that generation of lineage‐restricted precursors is coordinately regulated by gradients of the secreted factors BMPs and LIF/CNTF during development of dorsal forebrain. © 2006 Wiley‐Liss, Inc.
Astrogliosis in EAE spinal cord: Derivation from radial glia, and relationships to oligodendroglia
Authors: Bannerman Peter , Hahn Ashleigh , Soulika Athena , Gallo Vittorio , Pleasure David
Published: September 2006

A prominent feature of multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) is the accumulation of enlarged, multipolar glial fibrillary acidic protein (GFAP) and brain lipid binding protein (BLBP) immunoreactive astroglia within and at the margins of the inflammatory demyelinative lesions. Whether this astrogliosis is due to both astroglial hyperplasia and hypertrophy or solely to astroglial hypertrophy is controversial. We now report that coincident with the first appearance of inflammation and clinical deficits in mice with myelin oligodendrocyte glycoprotein peptide (MOG peptide)‐induced EAE, the radially oriented, bipolar, GFAP, and BLBP positive cells (adult radial glia) present in normal spinal cord white matter undergo mitosis and phenotypic transformation to hypertrophic astroglia. To facilitate visualization of relationships between these hypertrophic astroglia and dying and regenerating oligodendroglia, we used mice that express enhanced green fluorescent protein (EGFP) in cells of the oligodendroglial lineage. During the first week after onset of illness, markedly swollen EGFP+ cells without processes were seen within lesions, whereas EGFP+ cells that expressed immunoreactive cleaved caspase‐3 were uncommon. These observations support the hypothesis that necrosis contributes to oligodendroglial loss early in the course of EAE. Later in the illness, EGFP+ cells accumulated amongst hypertrophic astroglia at the margins of the lesions, while the lesions themselves remained depleted of oligodendroglia, suggesting that migration of oligodendroglial lineage cells into the lesions was retarded by the intense perilesional gliosis. © 2006 Wiley‐Liss, Inc.
Effectiveness of health management departments of universities that train health managers in Turkey
Authors: Karagoz Sevgul , Balci Ali
Published: September 2006

In this research, it was aimed to examine the effectiveness of health management departments of universities that train health managers in Turkey. The study was taken on hand as comparative in respect to positions (lecturers and students) and variables of universities. Organisational effectiveness was attempted to describe in nine dimensions by being inspired from Cameron's study. Factor analysis was used for construction validity of the scale developed by the researcher. For internal consistency and reliability, Cronbach Alpha reliability coefficient and item total correlation were applied. A questionnaire was applied on total 207 persons in health management departments that form up the population in Turkey. In analysis of data were descriptive statistics and t‐test used. According to research findings, at university level, lecturers found their departments more effective than their students. The highest effectiveness was perceived at Baskent University (private). In total belonging to each dimension, the perceptions of lecturers realised on a higher level compared to those of students. It was found that the effectiveness, which was the highest dimension, was the organisational health and the ability to acquire source the lowest dimension. Effectiveness level was found to be moderate in general total. Copyright © 2006 John Wiley & Sons, Ltd.
The potential roles of biological soil crusts in dryland hydrologic cycles
Authors: Belnap Jayne
Published: September 2006

Biological soil crusts (BSCs) are the dominant living cover in many drylands of the world. They possess many features that can influence different aspects of local hydrologic cycles, including soil porosity, absorptivity, roughness, aggregate stability, texture, pore formation, and water retention. The influence of biological soil crusts on these factors depends on their internal and external structure, which varies with climate, soil, and disturbance history. This paper presents the different types of biological soil crusts, discusses how crust type likely influences various aspects of the hydrologic cycle, and reviews what is known and not known about the influence of biological crusts on sediment production and water infiltration versus runoff in various drylands around the world. Most studies examining the effect of biological soil crusts on local hydrology are done by comparing undisturbed sites with those recently disturbed by the researchers. Unfortunately, this greatly complicates interpretation of the results. Applied disturbances alter many soil features such as soil texture, roughness, aggregate stability, physical crusting, porosity, and bulk density in ways that would not necessarily be the same if crusts were not naturally present. Combined, these studies show little agreement on how biological crusts affect water infiltration or runoff. However, when studies are separated by biological crust type and utilize naturally occurring differences among these types, results indicate that biological crusts in hyperarid regions reduce infiltration and increase runoff, have mixed effects in arid regions, and increase infiltration and reduce runoff in semiarid cool and cold drylands. However, more studies are needed before broad generalizations can be made on how biological crusts affect infiltration and runoff. We especially need studies that control for sub‐surface soil features such as bulk density, micro‐ and macropores, and biological crust structure. Unlike the mixed effects of biological crusts on infiltration and runoff among regions, almost all studies show that biological crusts reduce sediment production, regardless of crust or dryland type.Copyright © 2006 John Wiley & Sons, Ltd.
Riparian ecohydrology: regulation of water flux from the ground to the atmosphere in the Middle Rio Grande, New Mexico
Authors: Cleverly James R. , Dahm Clifford N. , Thibault James R. , McDonnell Dianne E. , Allred Coonrod Julie E.
Published: September 2006

During the previous decade, the south‐western United States has faced declining water resources and escalating forest fires due to long‐term regional drought. Competing demands for water resources require a careful accounting of the basin water budget. Water lost to the atmosphere through riparian evapotranspiration (ET) is believed to rank in the top third of water budget depletions. To better manage depletions in a large river system, patterns of riparian ET must be better understood. This paper provides a general overview of the ecological, hydrological, and atmospheric issues surrounding riparian ET in the Middle Rio Grande (MRG) of New Mexico. Long‐term measurements of ET, water table depth, and micro‐meteorological conditions have been made at sites dominated by native cottonwood (Populus deltoides) forests and non‐native saltcedar (Tamarix chinensis) thickets along the MRG. Over periods longer than one week, groundwater and leaf area index (LAI) dynamics relate well with ET rates. Evapotranspiration from P. deltoides forests was unaffected by annual drought conditions in much of the MRG where the water table is maintained within 3 m of the surface. Evapotranspiration from a dense Tamarix chinensis thicket did not decline with increasing groundwater depth; instead, ET increased by 50%, from 6 mm/day to 9 mm/day, as the water table receded at nearly 7 cm/day. Leaf area index of the T. chinensis thicket, likewise, increased during groundwater decline. Leaf area index can be manipulated as well following removal of non‐native species. When T. chinensis and non‐native Russian olive (Elaeagnus angustifolia) were removed from a P. deltoides understory, water salvaged through reduced ET was 26 cm/yr in relation to ET measured at reference sites. To investigate correlates to short‐term variations in ET, stepwise multiple linear regression was used to evaluate atmospheric conditions under which ET is elevated or depressed. At the P. deltoides‐dominated sites, ET anomalies were positively correlated to net radiation (Rn) and negatively correlated to sensible heat flux (H), cross‐corridor wind speed (v), and along‐corridor wind speed (u) (r2 = 0·54). At the T. chinensis‐dominated sites, ET anomalies were positively correlated with Rn, u, the friction coefficient (u*), and vapour pressure deficit (VPD) and were negatively correlated to surface humidity scale (q*), daily high and low temperature, H, and precipitation (r2 = 0·66). Both Tamarix and Populus can transpire prodigious quantities of water when conditions are favourable. In the MRG, T. chinensis is preferentially found where summer flooding and cold air drainage occurs, and P. deltoides is preferentially located in areas with shallow groundwater within 2 m of the surface. Copyright © 2006 John Wiley & Sons, Ltd.
Runoff and erosion from Australia's tropical semi‐arid rangelands: influence of ground cover for differing space and time scales
Authors: Bartley Rebecca , Roth Christian H. , Ludwig John , McJannet David , Liedloff Adam , Corfield Jeff , Hawdon Aaron , Abbott Brett
Published: September 2006

This paper highlights the relevant issues influencing the amount and arrangement of ground cover in savanna rangelands in Australia, and presents field measurements from hillslope scale flumes, which demonstrate how runoff and sediment loss vary with spatial patterns in ground cover. Hillslopes with relatively high mean cover, but with small patches bare of vegetation, are shown to have between 6 and 9 times more runoff, and up to 60 times more sediment loss than similar hillslopes that do not contain bare patches. The majority of sediment lost from the hillslopes is composed of fine (suspended) rather than coarse (bedload) material, although the absolute sediment loads are comparatively low. These low loads are considered to be the result of lower than average rainfall during the measurement period (2002–2005) and the high and prolonged rates of historical hillslope erosion that have exhausted the erodible material from the A‐horizon. The collected data also demonstrate that a large proportion of soil is lost during the initial ‘flushing’ period of runoff events.

The results presented have important implications for the management of savanna grazing systems by highlighting (i) the significance of bare patches in contributing to runoff and soil loss from hillslopes; (ii) the importance of having medium to high cover patches at the bottom of hillslopes for trapping and storing sediment and therefore reducing its entry into the stream network; and (iii) how maintenance of ground cover during the dry season reduces sediment concentrations in runoff occurring early in the wet season. Copyright © 2006 John Wiley & Sons, Ltd.