bluuebunny/crossref_metadata_2025 huggingface dataset:
FURTHER EXAMINATION OF FACTORS THAT INFLUENCE PREFERENCE FOR POSITIVE VERSUS NEGATIVE REINFORCEMENT
Authors: Kodak Tiffany , Lerman Dorothea C. , Volkert Valerie M. , Trosclair Nicole
Published: October 2007

Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional reinforcer during treatment (DeLeon, Neidert, Anders, & Rodriguez‐Catter, 2001; Final acceptance Lalli et al., 1999). However, a number of variables may influence choice between concurrently available forms of reinforcement. An analogue for treatment situations in which positive reinforcement for compliance is in direct competition with negative reinforcement for problem behavior was used in the current study to evaluate several variables that may influence choice. Participants were 5 children who had been diagnosed with developmental disabilities and who engaged in problem behavior maintained by escape from demands. In the first phase, the effects of task preference and schedule of reinforcement on choice between a 30‐s break and a high‐preference food item were evaluated. The food item was preferred over the break, regardless of the preference level of the task or the reinforcement schedule, for all but 1 participant. In the second phase, the quality of the break was manipulated by combining escape with toys, attention, or both. Only 1 participant showed preference for the enriched break. In the third phase, choice of a medium‐ or low‐preference food item versus the enriched break was evaluated. Three of 4 participants showed preference for the break over the less preferred food item. Results extend previous research by identifying some of the conditions under which individuals who engage in escape‐maintained behavior will prefer a food reinforcer over the functional one.
ASSESSMENT AND TREATMENT OF PROBLEM BEHAVIOR OCCASIONED BY INTERRUPTION OF FREE‐OPERANT BEHAVIOR
Authors: Hagopian Louis P. , Bruzek Jennifer L. , Bowman Lynn G. , Jennett Heather K.
Published: October 2007

The current study describes the assessment and treatment of the problem behavior of 3 individuals with autism for whom initial functional analysis results were inconclusive. Subsequent analyses revealed that the interruption of free‐operant behavior using “do” requests (Study 1) as well as “do” and “don't” requests (Study 2) occasioned problem behavior. Initially, treatment involved differential and noncontingent reinforcement without interruption. To make the intervention more sustainable in the natural environment (where interruptions are unavoidable), a two‐component multiple‐schedule arrangement was used to progressively increase the period of time in which ongoing activities would be interrupted. During generalization sessions, the intervention was applied across a variety of contexts and therapists.
Deepwater Drilling Made More Efficient and Cost-Effective Using the Microflux Control Method and an Ultralow Invasion Fluid to Open the Mud-Weight Window
Authors: Santos Helio , Reid Paul , McCaskill John , Kinder Joe , Kozicz John
Published: October 2007

A common major challenge in deepwater drilling is the narrow margin between pore pressure and fracture gradient. In many basins, deepwater wells are becoming even more challenging, with subsalt and deeper horizons introducing problems that can lead to well abandonment before the target depth (TD) is reached. The key to drilling these wells safely and cost-effectively is to use technologies, methods, and procedures that allow the mud-weight window to be widened.

This paper describes two technologies that, when combined, can widen the effective mud-weight window significantly. One is the Micro-Flux Control (MFC) method. This is a closed-loop drilling system that allows the safe use of a mud weight as close as possible to the pore pressure. The other technology is an ultralow invasion-drilling fluid (ULIF) that increases the leakoff pressure of the openhole section, thereby opening the mud-weight window. Several field cases involving the drilling fluid are described, with increases of more than 1.5 lbm/gal in the leakoff pressure observed in wells in the Gulf of Mexico (GOM).

Results obtained with the MFC method at a test facility in the USA are described. These show the ability of the method to deal very effectively with any influx or loss.

Significant operational savings have already been obtained with the drilling fluid. However, the combination of the two technologies will produce a step change in safety, technical capability, and economics in many deepwater operations.
Marco Polo Tension Leg Platform: Deepwater Completion Performance
Authors: Burman Jack , Renfro Kevin , Conrad Mark
Published: October 2007

Novel well completion techniques and exceptional field execution (per Dodson Completion Performance Database) allowed the six well completions on the Anadarko operated Marco Polo Deepwater Tension Leg Platform (TLP) project in Green Canyon (GC) block 608 to be accomplished significantly ahead of schedule. All six wells (17 frac packs) were placed on production in approximately 168 days (including 14 days lost because of storms) after riser tieback operations were complete. An operational efficiency of 85%, with weather downtime accounting for 9% and other lost time accounting for 6%, was obtained during the completion campaign.

This paper will focus on how the implementation challenges of completing 17 zones in six deepwater dry-tree wells with a 1,000hp rig were met, and will highlight a number of concepts and "technical firsts" that can be applied to other deepwater-development projects.
The possibility to prevent postoperative sensitivity in resin-based composite restored teeth
Authors: Manojlovic Dragica , Zupanjac Srdjan , Zivkovic Slavoljub
Published: October 2007

Introduction: Postoperative sensitivity is a common problem in patients after placement of resin-based composite (RBC) restorations. Aim: The of this study was to evaluate clinical efficacy of oxalate desensitizer BisBlock in the prevention of postoperative sensitivity after placement of RBC restorations. Materials and Methods: This clinical study was conducted at Belgrade University School of Dentistry Department of Restorative Dentistry and Endodontics. The study comprised 31 patients, both sexes, aged 18 - 32. In each patient, two class II cavities were prepared in premolars (62 cavities) and restored with RBCs. One restored tooth in each patient was treated with BisBlock (experimental group) while another served as control. In the restorative procedure, Single Bond (3M ESPE) was used as the adhesive and teeth were restored with Valux Plus (3M ESPE) RBC. Sensitivity evaluation was performed at day 1, day 4 and day 7 after restoration and comprised sensitivity on thermal and osmotic stimuli as well as sensitivity during mastication. Results: The obtained results revealed statistically significant decrease of postoperative sensitivity in experimental (3.23%) than control group (16.14%). .
Metformin Inhibits Hepatic Gluconeogenesis Through AMP-Activated Protein Kinase–Dependent Regulation of the Orphan Nuclear Receptor SHP
Authors: Kim Yong Deuk , Park Keun-Gyu , Lee Yong-Soo , Park Yun-Yong , Kim Don-Kyu , Nedumaran Balachandar , Jang Won Gu , Cho Won-Jea , Ha Joohun , Lee In-Kyu , Lee Chul-Ho , Choi Hueng-Sik
Published: October 2007

OBJECTIVE—Metformin is an antidiabetic drug commonly used to treat type 2 diabetes. The aim of the study was to determine whether metformin regulates hepatic gluconeogenesis through the orphan nuclear receptor small heterodimer partner (SHP; NR0B2).

RESEARCH DESIGN AND METHODS—We assessed the regulation of hepatic SHP gene expression by Northern blot analysis with metformin and adenovirus containing a constitutive active form of AMP-activated protein kinase (AMPK) (Ad-AMPK) and evaluated SHP, PEPCK, and G6Pase promoter activities via transient transfection assays in hepatocytes. Knockdown of SHP using siRNA SHP was conducted to characterize the metformin-induced inhibition of hepatic gluconeogenic gene expression in hepatocytes, and metformin–and adenovirus SHP (Ad-SHP)–mediated hepatic glucose production was measured in B6-Lepob/ob mice.

RESULTS—Hepatic SHP gene expression was induced by metformin, 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR), and Ad-AMPK. Metformin-induced SHP gene expression was abolished by adenovirus containing the dominant negative form of AMPK (Ad-DN-AMPK), as well as by compound C. Metformin inhibited hepatocyte nuclear factor-4α–or FoxA2-mediated promoter activity of PEPCK and G6Pase, and the inhibition was blocked with siRNA SHP. Additionally, SHP knockdown by adenovirus containing siRNA SHP inhibited metformin-mediated repression of cAMP/dexamethasone-induced hepatic gluconeogenic gene expression. Furthermore, oral administration of metformin increased SHP mRNA levels in B6-Lepob/ob mice. Overexpression of SHP by Ad-SHP decreased blood glucose levels and hepatic gluconeogenic gene expression in B6-Lepob/ob mice.

CONCLUSIONS—We have concluded that metformin inhibits hepatic gluconeogenesis through AMPK-dependent regulation of SHP.
In Vivo Evidence for Inverse Agonism of Agouti-Related Peptide in the Central Nervous System of Proopiomelanocortin-Deficient Mice
Authors: Tolle Virginie , Low Malcolm J.
Published: October 2007

OBJECTIVE—Melanocyte-stimulating hormone (MSH) peptides processed from proopiomelanocortin (POMC) regulate energy homeostasis by activating neuronal melanocortin receptor (MC-R) signaling. Agouti-related peptide (AgRP) is a naturally occurring MC-R antagonist but also displays inverse agonism at constitutively active melanocortin-4 receptor (MC4-R) expressed on transfected cells. We investigated whether AgRP functions similarly in vivo using mouse models that lack all neuronal MSH, thereby precluding competitive antagonism of MC-R by AgRP.

RESEARCH DESIGN AND METHODS—Feeding and metabolic effects of the MC-R agonist melanotan II (MTII), AgRP, and ghrelin were investigated after intracerebroventricular injection in neural-specific POMC-deficient (Pomc−/−Tg/+) and global POMC-deficient (Pomc−/−) mice. Gene expression was quantified by RT-PCR.

RESULTS—Hyperphagic POMC-deficient mice were more sensitive than wild-type mice to the anorectic effects of MTII. Hypothalamic melanocortin-3 (MC3)/4-R mRNAs in POMC-deficient mice were unchanged, suggesting increased receptor sensitivity as a possible mechanism for the heightened anorexia. AgRP reversed MTII-induced anorexia in both mutant strains, demonstrating its ability to antagonize MSH agonists at central MC3/4-R, but did not produce an acute orexigenic response by itself. The action of ghrelin was attenuated in Pomc−/−Tg/+ mice, suggesting decreased sensitivity to additional orexigenic signals. However, AgRP induced delayed and long-lasting modifications of energy balance in Pomc−/−Tg/+, but not glucocorticoid-deficient Pomc−/− mice, by decreasing oxygen consumption, increasing the respiratory exchange ratio, and increasing food intake.

CONCLUSIONS—These data demonstrate that AgRP can modulate energy balance via a mechanism independent of MSH and MC3/4-R competitive antagonism, consistent with either inverse agonist activity at MC-R or interaction with a distinct receptor.
The Effect of Warm Inhalation Therapy on the Ciliated Nasal Epithelium
Authors: Deitmer T.
Published: October 2007

It is well known from in vitro studies that the function of the ciliary epithelium is temperature dependent. The ciliary beat is irreversibly arrested above about 40° to 45°C. We exposed 30 volunteers to inhalation therapy with hot moist vapor of about 50°C. The function of the nasal mucosa was assessed. Ciliary beat frequency and the percentage of dead and viable ciliated cells from a viable cytological sampling of the nose were counted before and after treatment. The percentage of cell composition was the same whereas the ciliary beat frequency rose. The temperature in the mucosal layer probably is not as high as in the inhaled vapor due to the air-conditioning capacity of the nose, and thus the ciliated cells seem to be protected from adverse effects that might result from high temperatures in inhaled gases.
Inhibitory Effect of Half-face Masks on Inhalation of Particles of Carbon Powder and Japanese Cedar Pollen
Authors: Xiao S. F. , Okuda M. , Tanimoto H.
Published: October 2007

We examined the inhibitory effect of half-face masks on inhalations of particles of carbon powder and Japanese cedar pollen from the point of view of preventing nasal manifestation in pollinosis patients. The subjects tried out two types of simple masks commonly sold at drug stores or supermarket chains. With each type of mask, two different sizes of carbon particles and Japanese cedar pollen (which were dispersed in canisters) were inhaled by the subjects, and the particles inside and outside the mask were counted. The face masks inhibited inhalation of particles in air, and these simple economical cotton gauze masks, if used dampened with plain water, were comparable in effect to more expensive industrial masks.
Management of Orbital Hematoma following Functional Endoscopic Sinus Surgery
Authors: May Mark , Hillsamer Peter , Hoffmann Dieter F.
Published: October 2007

One in a series of 500 consecutive patients who underwent functional endoscopic sinus surgery suffered a major complication of the procedure, an orbital hematoma with temporary blindness. This patient's case history is reported to illustrate successful management of this difficult problem.
Acoustic Rhinometry: A Study of Transient and Continuous Noise Techniques with Nasal Models
Authors: Djupesland Per G. , Qian Wei , Furlott Henry , Røtnes Jan Sigurd , Cole Philip , Zamel Noe
Published: October 2007

The objective of this study is to compare the properties of two of the most frequently used acoustic rhinometers: the EcoVision (Hood Laboratories, USA) using the transient technique, and the Rhin2100 (RhinoMetrics, Denmark) using the continuous wide-band technique. In the wide-band rhinometer (Rhin2100), the transient analog signals of traditional rhinometers (EcoVision), are replaced by a digitally produced continuous wide-band noise signal. Tubular models and a plastic model produced by stereolithography (SLA), representing the true replicate of the nasal anatomy, were used to compare the accuracy of the two rhinometers. The effect of increasing angling (0–50°) between the sound wave tube and the cavity was evaluated in a tubular model. The curves obtained with the two rhinometers showed close similarity, and the acoustically derived volumes correlated well with the volumes of tubular (% error < 4%) as well as the complex nasal model (% error < 10.5%). Both rhinometers underestimated the minimum cross-sectional area (MCA) of the complex nasal model (mean % error complex model: Rhin2100 = –7.6%, EcoVision = –13%). The effect of increasing the angle between the nose adapter and the tubular models was small for both rhinometers (CV < 3% for MCA and CV < 1% for volumes). The similar, and in general, high accuracy of the two rhinometers evaluated, particularly in the complicated geometry of the SLA model, is an indication of the reliability of both. The small effect of changing the angle between the nose adapter and the models was unexpected and very encouraging. Nevertheless, some minor differences in performance and capabilities of the two rhinometers might influence interpretation and comparison of results. Further comparisons in a clinical setting are under current investigation.
The Effects of Nasal Massage of the “Yingxiang” Acupuncture Point on Nasal Airway Resistance and Sensation of Nasal Airflow in Patients with Nasal Congestion Associated with Acute Upper Respiratory Tract Infection
Authors: Takeuchi Hiromi , Jawad Martez S.M. , Eccles Ronald
Published: October 2007

The aim of our study was to determine whether nasal massage of the “yingxiang” acupuncture point in patients with nasal congestion had any effect on nasal airway resistance (NAR) measured by posterior rhinomanometry and sensation of nasal airflow measured on a visual analog scale (VAS). Twenty patients were randomized into two groups; one group self massaged the yingxiang point for 30 seconds, while the other group acted as control group without nasal massage. NAR and VAS were measured at baseline, and at 2 and 10 minutes after massage. At the end of the study, patients were asked to score any change in their nasal congestion. There was no statistically significant difference between the two groups in percentage change in NAR or VAS from baseline at any time during the study, although the massage group showed trends toward decongestion and relief from congestion. At the end of the study, more patients in the massage group than the control group felt their nasal congestion was improved (p < 0.005). It is interesting that all three measures (NAR, VAS, and end question) showed that the nasal massage group had greater relief from nasal congestion than the control group. The results of this study, when taken together, indicate that nasal massage may provide some relief from nasal congestion and that further studies involving a larger patient population are warranted to determine whether nasal massage has a significant effect on NAR.
Endoscopically Guided Sinus Cultures in Normal Subjects
Authors: Nadel Douglas M. , Lanza Donald C. , Kennedy David W.
Published: October 2007

The study of healthy sinus flora has been pursued with Caldwell-Luc, antral puncture, and anterior rhinoscopy. Increasingly, nasal endoscopy has been used to obtain cultures, yet the significance of findings using this technique remains uncertain. Our ability to interpret the growing number of these cultures will be greatly enhanced by determining the results of this technique in patients without sinusitis. The goal of this study is to identify the bacterial flora of the sinuses in 25 healthy volunteers.

Gram stain, aerobic, and anaerobic cultures were performed on swabs taken from the middle meatus and sphenoethmoid recesses. Eighteen cultures were sterile for aerobic organisms. Of the remaining 32 cultures, 41 isolates were retrieved. Predominant aerobes were S. aureus, Staphylococcus coagulase-negative, and diphtheroids; P. acnes was the predominant anaerobe.
Endoscopic Sphenopalatine Artery Ligation is an Effective Method of Treatment for Posterior Epistaxis
Authors: Snyderman Carl H. , Goldman Steven A. , Carrau Ricardo L , Ferguson Berrylin J. , Grandis Jennifer R.
Published: October 2007

Transantral ligation of the internal maxillary artery is the most widely used surgical technique for control of intractable epistaxis. Although this technique is highly efficacious, significant complications may occur, including oroantral fistula, damage to the infraorbital nerve, and recurrent bleeding. An endoscopic transnasal approach for ligation of the terminal branch of the internal maxillary artery, the sphenopalatine artery, provides an alternative to transantral ligation. We have used endoscopic ligation of the sphenopalatine artery to treat 38 patients requiring surgical therapy for epistaxis. These cases were retrospectively reviewed to analyze the efficacy and morbidity of our technique. Five patients (13%) had significant recurrence of their epistaxis, of whom two required further surgical intervention. There were no major complications in this series. There were some minor sequelae including nasal crusting (34%) and paresthesia of the palate and nose (13%). The median hospital stay was 3 days (range 1 to 10). Endoscopic transnasal sphenopalatine artery ligation seems to be a safe and effective technique for management of posterior epistaxis.
The Wisdom of Class-Size Reduction
Authors: Graue Elizabeth , Hatch Kelly , Rao Kalpana , Oen Denise
Published: October 2007

In this study, the authors explore the implementation of a statewide class-size reduction program in nine high-poverty schools. Through qualitative methods, they examined how schools used class-size reduction to change staffing patterns and instructional programs. Requiring changes in space allocation, class-size reduction was accomplished through attention to pupil:teacher ratio, with classes ranging from 15:1 to 30:2 team taught. Most partner classes used tag-team teaching, with one teacher leading and the other doing clerical work. Working without specific professional development to enhance teaching in smaller classes, it made sense that teachers continued to solo practice. Class-size reduction is both a programmatic and instructional reform, and as such, it requires specific professional development to promote change.
Do Accountability Policy Sanctions Influence Teacher Motivation? Lessons From Chicago’s Low-Performing Schools
Authors: Finnigan Kara S. , Gross Betheny
Published: October 2007

The federal No Child Left Behind Act and previous performance-based accountability policies are based on a theoretical assumption that sanctions will motivate school staff to perform at higher levels and focus attention on student outcomes. Using data from Chicago, this article draws on expectancy and incentive theories to examine whether motivation levels changed as a result of accountability policies and the policy mechanisms that affected teacher motivation. Through a combination of qualitative and quantitative data, the authors found that the value teachers placed on their professional status and their goals for students focused and increased their effort, but low morale had the potential to undercut the sustainability of teachers’ responses.
Standard Error Estimation of 3PL IRT True Score Equating With an MCMC Method
Authors: Liu Yuming , Schulz E. Matthew , Yu Lei
Published: October 2007

A Markov chain Monte Carlo (MCMC) method and a bootstrap method were compared in the estimation of standard errors of item response theory (IRT) true score equating. Three test form relationships were examined: parallel, tau-equivalent, and congeneric. Data were simulated based on Reading Comprehension and Vocabulary tests of the Iowa Tests of Basic Skills®. For parallel and congeneric test forms within valid IRT true score ranges, the pattern and magnitude of standard errors of IRT true score equating estimated by the MCMC method were very close to those estimated by the bootstrap method. For tau-equivalent test forms, the pattern of standard errors estimated by the two methods was also similar. Bias and mean square errors of equating produced by the MCMC method were smaller than those produced by the bootstrap method; however, standard errors were larger. In educational testing, the MCMC method may be used as an additional or alternative procedure to the bootstrap method when evaluating the precision of equating results.
Tesaglitazar, as add-on therapy to sulphonylurea, dose-dependently improves glucose and lipid abnormalities in patients with type 2 diabetes
Authors: Wilding John PH , Gause-Nilsson Ingrid , Persson Anders
Published: October 2007

This randomised, double-blind, parallel-group, mul-ticentre study investigated the effects of the dual peroxisome proliferator-activated receptor (PPAR) α/γ agonist, tesaglitazar (0.5 and 1 mg), as add-on treatment in 568 patients with type 2 diabetes that was poorly controlled with sulphonylurea therapy titrated to the highest tolerated dose.

There was a significant placebo-corrected reduction in glycosylated haemoglobin (HbA1C) from baseline to week 24 with tesaglitazar 0.5 mg and 1 mg (mean [95% confidence interval]: −0.93% [-1.09, −0.77] and −1.3% [-1.46, −1.14]; p<0.0001). Significant reductions were observed in insulin, fasting plasma glucose (FPG), triglyceride (all p<0.001) and non-high-density lipoprotein (HDL) cholesterol (p<0.001). Tesaglitazar increased levels of HDL-cholesterol (p<0.0001), adiponectin (p<0.0001) and leptin (p<0.001), but was associated with dose-dependent increases in serum creatinine and decreases in haemoglobin.

This study showed improvements in glycaemic control and dyslipidaemia in patients with type 2 diabetes poorly controlled with existing sulphonylurea therapy. Although tesaglitazar has now been discontinued from clinical development, these results remain relevant to future research into PPAR agonists.
Renin-angiotensin system expression in the K562 human erythroleukaemic cell line
Authors: Koca Ebru , Haznedaroglu Ibrahim C , Acar Kadir , Beyazit Yavuz , Aksu Salih , Misirlioglu Muge , Tuncer Serdar , Sayinalp Nilgun , Ozcebe Osman I , Uner Aysegul
Published: October 2007

Local renin-angiotensin system (RAS) may affect leukaemic cell production within the bone marrow microenvironment.Angiotensin-converting enzyme (ACE), renin, and angiotensin could influence leukaemogenesis. In this study, mRNA expressions of the major RAS components (ACE, renin, and angiotensinogen) in K562 human erythroleukaemia cell line have been searched by Real Time quantitative polymerase chain reaction. K562 blasts are multipotential, haematopoietic malignant cells that spontaneously differentiate into recognisable progenitors of the erythrocyte, granulocyte and monocytic series.We observed significant expressions of ACE, renin, and angiotensinogen in K562 leukaemic blast cells.Therefore, K562 human erythroleukaemia cell line may serve as an in vitro model to elucidate the role of RAS in leukaemia and to test the effects of RAS-affecting drugs on leukaemic cellular proliferation.
Universal 2‐(4‐Nitrophenyl)ethyl and 2‐(4‐Nitrophenyl)ethoxycarbonyl Protecting Groups for Nucleosides and Nucleotides
Authors: Pfleiderer Wolfgang
Published: October 2007

A universal blocking group strategy for nucleobases is described, using the 2‐(4‐nitrophenyl)ethyl (NPE) group for O4‐T‐, O4‐U‐, O6‐dG‐, and O6‐G‐protection as well as the 2‐(4‐nitrophenyl)ethoxycarbonyl (NPEOC) group for amino protection in dC, C, dA, A, dG, and G. Conversion into the corresponding 5′‐O‐dimethoxytrityl derivatives and subsequent phosphitylation to form the fully protected 3′‐O‐(2‐cyanoethyl‐N,N‐diisopropylphosphoramidites) and 3′‐O‐(2‐(4‐nitrophenyl)ethyl‐N,N‐diisopropylphosphoramidites) produces a new class of interesting building blocks for oligonucleotide synthesis. Curr. Protoc. Nucleic Acid Chem. 30:2.13.1‐2.13.25. © 2007 by John Wiley & Sons, Inc.
A Universal and Recyclable Solid Support for Oligonucleotide Synthesis
Authors: Morvan François , Meyer Albert , Vasseur Jean‐Jacques
Published: October 2007

This unit provides a modified phosphoramidite method to synthesize oligodeoxyribonucleotides onto a universal and reusable hydroxyl solid support thanks to the use of deoxyribonucleoside tert‐butyl and cyanoethyl phosphoramidites. The nucleoside tert‐butyl phosphoramidite allows the introduction of an H‐phosphonate diester linkage using the phosphoramidite method. After elongation, the H‐phosphonate diester linker is cleaved by transesterification under mild basic conditions to yield an oligonucleotide with free 3′‐ and 5′‐hydroxyls and the starting solid support. Thus, the solid support is easily recycled and used for a subsequent synthesis. In addition, a nucleoside tert‐butyl phosphoramidite could be introduced inside the oligonucleotide chain during the elongation to yield a second H‐phosphonate diester linkage. After elongation, the two H‐phosphonate diester linkages are cleaved, producing two oligonucleotides with free 3′‐ and 5′‐hydroxyls. Curr. Protoc. Nucleic Acid Chem. 30:3.16.1‐3.16.19. © 2007 by John Wiley & Sons, Inc.
Analysis of Regulated Secretion Using PC12 Cells
Authors: Taupenot Laurent
Published: October 2007

The catecholamine‐secreting PC12 cell line derived from the rat adrenal medulla has long been considered a model system for neurosecretion and neuronal differentiation. PC12 cells contain a large number of secretory granules (otherwise known as large dense‐core vesicles) for storage of small molecules, processing enzymes, neuropeptides, and peptide hormones. Secretory granule exocytosis in PC12 cells is tightly regulated by calcium and occurs in response to a secretagogue. This unit provides protocols for maintenance and transfection of PC12 cells. Several secretion assays are described to measure the release of secretory granule cargo molecules by detection of radioactive catecholamine, or by immunochemical or chemiluminescence detection of transfected regulated secretory proteins. Curr. Protoc. Cell Biol. 36:15.12.1‐15.12.13. © 2007 by John Wiley & Sons, Inc.
Identifying Structural Noncoding RNAs Using RNAz
Authors: Washietl Stefan , L. Hofacker Ivo
Published: October 2007

The functions of many noncoding RNAs and cis‐acting regulatory elements of mRNAs depend on a defined RNA secondary structure. RNAz predicts such functional RNA structures on the basis of thermodynamic stability and evolutionary conservation of homologous sequences. It can be used to efficiently filter multiple alignments for noncoding RNA candidates in genomic screens. Curr. Protoc. Bioinform. 19:12.7.1‐12.7.18. © 2007 by John Wiley & Sons, Inc.
Gene Expression Analysis of RNA Purified from Embryonic Stem Cells and Embryoid Body–Derived Cells Using a High‐Throughput Microarray Platform
Authors: Player Audrey , Wang Yonghong , Rao Mahendra , Kawasaki Ernest
Published: October 2007

In this unit, starting with purified RNA, experimental protocols for performing microarrray expression analysis of embryonic stem cell lines compared to their corresponding differentiated embryoidal bodies are described. Methods for data analysis are suggested, with the goal of determining which genes are differentially expressed between the preparations. As an example, the use of the Affymetrix microarray expression platform is described, but alternative experimental options for analysis of RNA transcript levels are also summarized. This unit suggests quality control metrics, summazrizes the critical parameters necessary for obtaining reproducible experimental results, and outlines quantitative PCR methods for validating microarray results. Curr. Protoc. Stem Cell Biol. 2:1B.2.1‐1B.2.36. © 2007 by John Wiley & Sons, Inc.
Inside Front Cover: Combinatorial Modification of Degradable Polymers Enables Transfection of Human Cells Comparable to Adenovirus (Adv. Mater. 19/2007)
Authors: Green J. J. , Zugates G. T. , Tedford N. C. , Huang Y.‐H. , Griffith L. G. , Lauffenburger D. A. , Sawicki J. A. , Langer R. , Anderson D. G.
Published: October 2007

On p. 2836, Daniel G. Anderson and co‐workers report the development of end‐modified poly(β‐amino ester)s that are able to deliver DNA to primary human umbilical vein endothelial cells at levels comparable to adenovirus at a Multiplicity of Infection between 100 and 500, and two orders of magnitude better than the commonly used non‐viral polymeric vector, poly(ethylene imine). Small structural changes were found to have dramatic effects on multiple steps of gene delivery including the DNA binding affinity, nanoparticle size, intracellular DNA uptake, and final protein expression. In vivo, these polymer modifications enhance DNA delivery to ovarian tumors.
Dual catalyst bed for the oxidation of CH4 simultaneously to C2H4 and syngas
Authors: Hu Changwei , Wu Jingjing , Zhang Haili , Qin Song
Published: October 2007

Dual catalyst bed system was introduced into the conversion of methane in one reactor simultaneously to ethylene and syngas with appropriate concentrations, which could be used for further production of propanal via hydroformylation. To avoid the over consumption of O2 on the first catalyst bed, the moderately active catalyst Co/γ‐Al2O3 for methane partial oxidation was employed, followed by Na2WO4/Mn/SiO2 catalyst, which was one of the most effective catalysts for the oxidative coupling of methane. The distribution of products could be tuned by controlling the relative dosages of the two catalysts and the reaction conditions. A mixture with the desired composition of CO/H2/C2H4 = 1.1/1/1.2 was achieved, with the total yield of CO and C2H4 of about 18.5%, under the following optimized conditions: F = 150 cm3/min, CH4/O2 = 3, M1:M2 = 0.01 g:0.16 g (1: Co/γ‐Al2O3; 2: Na2WO4/Mn/SiO2). © 2007 American Institute of Chemical Engineers AIChE J, 2007
Prolonged half‐life of argatroban in patients with renal dysfunction and antiphospholipid antibody syndrome being treated for heparin‐induced thrombocytopenia
Authors: Athar Uzma , Husain Juhi , Hudson Jane , Lynch Jennie , Gajra Ajeet
Published: October 2007

Argatroban is a direct thrombin inhibitor approved for the treatment of heparin‐induced thrombocytopenia (HIT) type II. Argatroban is predominantly metabolized in the liver. It is widely believed that no dosage adjustment is required in patients with renal insufficiency, making it a preferred agent in patients on renal replacement therapy (Reddy and Grossman, Ann Pharm 2005;39:1601–1605). The elimination half‐life of argatroban is ∼50 min. Lupus anticoagulants can cause baseline elevation of the PTT and hence it is difficult to monitor the effects of anticoagulants such as heparin, lepirudin, or argatroban in patients with antiphospholipid antibody syndrome. Heparin levels may be used as an alternative for heparin monitoring but plasma levels of argatroban are not commercially available. A chromogenic antifactor IIa assay could be useful for monitoring argatroban in the presence of a lupus anticoagulant, but it is not widely available at present. We report a patient with end‐stage renal disease, maintained on peritoneal dialysis with HIT, who demonstrated a markedly prolonged half‐life when treated with argatroban despite the discontinuation of therapy. This case also demonstrates the lack of guidelines for the monitoring of argatroban therapy in the presence of an underlying lupus anticoagulant. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
The identification of microdeletion syndromes and other chromosome abnormalities: Cytogenetic methods of the past, new technologies for the future
Authors: Shaffer Lisa G. , Bejjani Bassem A. , Torchia Beth , Kirkpatrick Susan , Coppinger Justine , Ballif Blake C.
Published: October 2007

Chromosome analysis is an important diagnostic tool in the identification of causes of mental retardation, developmental delay, and other developmental disabilities. Cytogenetic approaches have revealed the chromosomal basis of a large number of genetic syndromes. The recent use of microarray‐based comparative genomic hybridization (array CGH) has accelerated the identification of novel cytogenetic abnormalities. We present the results of array CGH in 8,789 clinical cases submitted for a variety of developmental problems. Of these cases, 6.9% showed clinically relevant abnormalities, 1.2% showed benign copy‐number variants (polymorphisms), 2.5% showed recurrent alterations of unclear clinical significance—many of which are likely to be polymorphisms—and 1.4% showed novel alterations of unclear relevance. Although cytogenetic methods, including array CGH, have great potential for identifying novel chromosomal syndromes, this high‐resolution analysis may also result in diagnostic challenges imposed on laboratories and clinicians regarding findings of unclear clinical significance. © 2007 Wiley‐Liss, Inc.
Mother–offspring associations in Northern muriquis, Brachyteles hypoxanthus
Authors: Tolentino Karynna , Roper James J. , Passos Fernando C. , Strier Karen B.
Published: October 2007

Maternal care of offspring is ubiquitous among primates, but its duration varies across species due to factors such as dispersal patterns and social dynamics, which influence opportunities for and potential benefits of maternal investment in older offspring, respectively. We examined mother‐offspring associations in wild northern muriquis (Brachyteles hypoxanthus), in which males are philopatric, females typically disperse before puberty, and social relationships among and between males and females are egalitarian. Associations were systematically recorded between ten mothers, each with two–six offspring in the study group, and all group members from August 2003–May 2004 at the RPPN‐Feliciano Miguel Abdala in Minas Gerais, Brazil. Infants of both sexes received similarly high percentages of their mothers' association time. Mothers without infants also maintained strong associations with their youngest juvenile sons. Mothers did not spend consistently more time associating with either juvenile or adult sons than daughters. Our finding of non‐preferential associations between muriqui mothers and their older male offspring suggests that extended maternal investment in offspring may be of minimal value in their egalitarian society compared with its value for species living in hierarchical societies. Am. J. Primatol. 70:301–305, 2008. © 2007 Wiley‐Liss, Inc.
Sorption of binary liquid mixtures in methacrylate‐based biomaterials; Simultaneous determination of the diffusion coefficients and the uptake fraction at equilibrium of the components of ethanol‐water mixtures by a new iterative method
Authors: Sideridou Irini D. , Papanastasiou Georgios E.
Published: October 2007

The present investigation is concerned with the development of a new iterative method permitting, for a Fickian sorption of a binary liquid mixture in thin polymer sheets, the simultaneous determination of the self‐diffusion coefficients of the components of the mixture, and their uptake fractions at equilibrium. The approach is based on a new equation describing a parallel Fickian sorption of the components of the mixture into thin polymer sheets. The procedure was tested with ideal and Monte Carlo simulated data. The method, applied to ideal simulated data that corresponded to various values of D1, D2 and f, perfectly extracted the desired parameters. The application of the method to Monte Carlo simulated data revealed that this method is fairly applicable even when the simulated data are considerably obscured by “noise”. Finally, the proposed method was successfully applied to the experimental data concerning the sorption kinetics of ethanol–water mixture (75 vol % in EtOH) at 37°C in thin polymeric sheets of triethyleneglycol dimethacrylate (TEGDMA). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Use of a biomaterial as a thickener for textile ink‐jet printing
Authors: Yuen C. W. M. , Ku S. K. A. , Kan C. W.
Published: October 2007

The feasibility of using chitosan as a thickener in the pretreatment print paste for textile ink‐jet printing was explored. An orthogonal analysis was used to determine the optimum conditions for using chitosan as a thickener in the pretreatment print paste and the effects of different process factors for achieving the best color yield in textile ink‐jet printing. With the help of the orthogonal analysis, the importance of different process factors was found to be in the order of (1) the amount of urea used, (2) the amount of chitosan used, (3) the amount of sodium bicarbonate used, and (4) the steaming time. On the basis of the results of the orthogonal analysis, the optimum conditions for using chitosan as a thickener for the pretreatment print paste were concluded to be 40 mL of chitosan, 10 g of urea, 8 g of sodium bicarbonate, and 5 min of steaming. According to an analysis of the results of different color fastness tests, chitosan could principally work as a pretreatment print paste thickener. However, the final color yield obtained from chitosan‐containing cotton fabrics depended greatly on the stage of the chitosan application. Nevertheless, the color fastness properties and the outline sharpness of the prints of cotton fabric were greatly improved by the chitosan treatment. A two‐bath chitosan treatment was developed to separate the chitosan from sodium bicarbonate and urea before it was padded onto the fabric surface to minimize the neutralization effect. On the basis of the results for the highest color yield obtained on the cotton fabric, it was confirmed that the two‐bath chitosan treatment was successfully developed. In addition, chitosan could impart higher antibacterial properties with a slight reduction in the tensile strength of the cotton fabric. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Development of correlation between potassium hydroxide number and conductivity of concentrated natural rubber latex
Authors: Walpalage S. , Ganga I. , Silva K. M. D.
Published: October 2007

Increase in the ion concentration in the medium was found to increase conductivity and potassium hydroxide number (KOH No) in natural rubber latex (NRL). Addition of long chain fatty acids can increase the ion concentration in the medium and stability of NRL. A series of concentrated natural rubber latex samples from three different areas with different soils and climatic conditions were tested for the parameters such as KOH No and conductivity. They have been measured over a period of 62 days, upon addition of soap to natural rubber latex concentrate. The result showed that there was a strong positive linear correlation between conductivity and KOH No. The regression equation to express the relationship between the variables has also been found. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Silica fiber–polybenzoxazine–syntactic foams; Processing and properties
Authors: Santhosh Kumar K. S. , Reghunadhan Nair C. P. , Ninan K. N.
Published: October 2007

Polybenzoxazine filled with chopped silica fibers and their syntactic foams of varying composition and densities were processed. The composition and density variations were achieved by regulating the relative concentrations of silica fiber and glass microballoons (MB). The variation of tensile, compressive, and flexural properties with change in composition was investigated. For the silica‐fiber filled materials, the property attained a maximum at about 40% volume content of fiber, and thereafter, the properties showed a diminishing trend. The incorporation of microspheres significantly lowered the strength of silica filled materials. However, the decrease in the specific flexural strength was less pronounced and the strength was unaffected beyond a certain microsphere content. During processing and mechanical testing, a large quantity of fibers was fractured, which reduced the strength of silica filled systems. The diminution in material strength on embedding microspheres is attributed to the presence of stress concentrating loci as evidenced from SEM analysis. The various factors leading to the property variation with composition are discussed with microscopic analyses, like clustering of fibers, crack propagation, fiber pull out, and debonding of fibers from resin phase. Dynamic mechanical analysis revealed an improved damping property for the filled materials in contrast to the unfilled polymer. The Tg (deduced from tan δ maximum from DMTA) decreased in silica fiber containing materials and on incorporating the MB, the values reverted back to that of the neat polymer. Both silica and MB conferred better thermal and thermooxidative stabilities to the polybenzoxazine. However, the degradation mechanism is nonoxidative in nature. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis of tercopolymer BA–MMA–VTES and surface modification of nano‐size Si3N4 with this macromolecular coupling agent
Authors: Xia Ru , Li Minghua , Zhang Yuchuan , Zhu Qingren , Qian Jiasheng
Published: October 2007

A new macromolecular coupling agent butyl acrylate (BA)‐methyl methacrylate (MMA)‐vinyl triethoxy silane (VTES) tercopolymer was synthesized using solution polymerization initiated by free radical initiator benzoyl peroxide (BPO) and dicumyl peroxide (DCP). Dodecylthiol is choosed as the chain transfer to control the molecule weight of this tercopolymer. The terpolymer's molecular structure was confirmed by FTIR and NMR, and its average molecular weight was determined by GPC. In this work, the tercopolymer BA–MMA–VTES is used for surface modification of silicon nitride (Si3N4) nanopowder. The structure surface properties and thermal stability of modified nano‐Si3N4 were systematically investigated by FTIR, TGA, TEM, and size distribution analyzer. The results show that the macromolecular coupling agent bonds covalently on the surface of nano‐sized Si3N4 particles and an organic coating layer is formed. The optimum loading of this macromolecular coupling agent BA–MMA–VTES tercopolymer is 5% (wt %) of nano‐sized Si3N4. TEM also reveals that modified nano‐Si3N4 possesses good dispersibility. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Melt viscosity reduction of polycarbonate with low molar mass liquid crystals
Authors: Motong Noppawan , Thongyai Supakanok , Clarke Nigel
Published: October 2007

The phase behavior and rheological behavior of low molar mass liquid crystal (LLC) and polycarbonate blends is firstly reported. The results of small angle light scattering (SALS) indicate that the LLC is miscible in the mixture for weight fractions of LLC less than 6%. Mixtures of two different liquid crystals with two different molecular weight of polycarbonate were prepared inside the miscible regime of the blends. Both the complex and steady shear viscosities of the blends were found to be significantly decreased upon addition of small amounts of liquid crystal (1% by weight). At low shear rate, the steady state shear viscosity was similar to the pure polycarbonate, whilst, at higher shear rates, three further regimes of behavior, as has been described for liquid crystals and liquid crystal polymers, were found despite the low concentration of LLC; hence, the rheological properties of the blends can be significantly modified by small concentrations of LLC (as low as 1%). The decrease in melt viscosity of polycarbonate that we observe upon addition of LLC is not due to lubrication effects at the interfaces, as shown by reproducible oscillatory shear flow sweeps. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
The influence of indexing practices and weighting algorithms on document spaces
Authors: Wolfram Dietmar , Zhang Jin
Published: October 2007

Index modeling and computer simulation techniques are used to examine the influence of indexing frequency distributions, indexing exhaustivity distributions, and three weighting methods on hypothetical document spaces in a vector‐based information retrieval (IR) system. The way documents are indexed plays an important role in retrieval. The authors demonstrate the influence of different indexing characteristics on document space density (DSD) changes and document space discriminative capacity for IR. Document environments that contain a relatively higher percentage of infrequently occurring terms provide lower density outcomes than do environments where a higher percentage of frequently occurring terms exists. Different indexing exhaustivity levels, however, have little influence on the document space densities. A weighting algorithm that favors higher weights for infrequently occurring terms results in the lowest overall document space densities, which allows documents to be more readily differentiated from one another. This in turn can positively influence IR. The authors also discuss the influence on outcomes using two methods of normalization of term weights (i.e., means and ranges) for the different weighting methods.
Extracting accurate and complete results from search engines: Case study windows live
Authors: Thelwall Mike
Published: October 2007

Although designed for general Web searching, Webometrics and related research commercial search engines are also used to produce estimated hit counts or lists of URLs matching a query. Unfortunately, however, they do not return all matching URLs for a search and their hit count estimates are unreliable. In this article, we assess whether it is possible to obtain complete lists of matching URLs from Windows Live, and whether any of its hit count estimates are robust. As part of this, we introduce two new methods to extract extra URLs from search engines: automated query splitting and automated domain and TLD searching. Both methods successfully identify additional matching URLs but the findings suggest that there is no way to get complete lists of matching URLs or accurate hit counts from Windows Live, although some estimating suggestions are provided.