bluuebunny/crossref_metadata_2025 huggingface dataset:
Insulin Resistance Syndrome in the Elderly
Authors: Banks William A. , Willoughby Lisa M. , Thomas David R. , Morley John E.
Published: August 2007

OBJECTIVE—Hyperinsulinemic euglycemia, or insulin resistance syndrome (IRS), is associated with increased morbidity and mortality. Although thought to be associated with proinflammatory states, little work has been done in this area. Here, we determined the impact of IRS on functional, biochemical, metabolic, and inflammatory status in a high-risk population: elderly women in nursing homes.

RESEARCH DESIGN AND METHODS—Functional, biochemical, metabolic, and inflammatory parameters were measured in 100 consecutive ambulatory, elderly women who resided in nursing homes. Diabetic subjects and residents with fasting blood glucose ≥110 mg/dl were excluded. Remaining residents were classified as insulin resistant (IR) (insulin >100 pmol/l) or non-IR (NIR).

RESULTS—A total of 16 residents were IR and 53 NIR. No differences in functional status, BMI, renal function, C-reactive protein, or immune cell levels were found. Fasting blood glucose was higher in IR subjects ([means ± SD] 94.1 ± 8.1 vs. 87.9 ± 8.2, P < 0.05), indicating a very mild glucose intolerance. Serum C-peptide (P < 0.05), amylin (P < 0.01), and leptin (P < 0.01), but not adiponectin or resistin, were higher in IR subjects. Higher leptin-to-BMI and insulin–to–C-peptide ratios suggested an increased percent body fat mass and altered clearance of insulin, respectively. Eleven of 13 cytokines had arithmetic elevations, but only tumor necrosis factor-α (TNF) reached statistical significance (P < 0.01). TNF and insulin levels were highly correlated.

CONCLUSIONS—IRS in the healthiest of long-term care residents is relatively rare but is associated with mild glucose intolerance, increased percent body fat, altered insulin clearance, and a proinflammatory status as evidenced by an elevated TNF.
The Effect of Resistance Training on Functional Capacity and Quality of Life in Individuals with High and Low Numbers of Metabolic Risk Factors
Authors: Levinger Itamar , Goodman Craig , Hare David L. , Jerums George , Selig Steve
Published: August 2007

OBJECTIVE—There are limited data on the effects of resistance training on the capacity to perform activities of daily living (ADLs) and quality of life (QoL) for individuals with a high number of metabolic risk factors (HiMF). In this study, we examined the effect of resistance training on the capacity to perform ADLs and QoL in individuals with HiMF and compared any benefits with individuals with a low number of metabolic risk factors (LoMF).

RESEARCH DESIGN AND METHODS—Fifty-five untrained individuals, aged 50.8 ± 6.5 years, were randomized to four groups: HiMF training (HiMFT), HiMF control, LoMF training (LoMFT), and LoMF control. At baseline and after 10 weeks of resistance training, participants underwent anthropometric measurements and assessments of aerobic power (Vo2peak), muscle strength, capacity to perform ADLs, and a self-perceived QoL questionnaire. A repeated-measures ANOVA was used to examine the effect of training over time among groups.

RESULTS—Training increased lean body mass in both HiMFT (P = 0.03) and LoMFT (P = 0.03) groups. Total fat content and Vo2peak improved in the LoMFT group only. Muscle strength improved in both training groups (P < 0.01). Time to complete ADLs was reduced by 8.8% in the LoMFT group (P < 0.01) and 9.7% in the HiMF group (P < 0.01). Only the HiMFT group reported improvement in QoL.

CONCLUSIONS— Resistance training improved muscle strength and the capacity to perform ADLs in individuals with HiMF and LoMF. Resistance training improved QoL for the HiMF group, and this result was independent of changes in body fat content or aerobic power. Longer training regimens may be needed to improve QoL in individuals with LoMF.
Current Trends in Weight Management: What Advice Do We Give to Patients?
Authors: Boucher Jackie L. , Benson Gretchen A. , Kovarik Stephanie , Solem Brianne , VanWormer Jeffery J.
Published: August 2007

In Brief

Given the number of individuals with diabetes who are overweight or obese,it is essential for diabetes educators to familiarize themselves with evidence related to common questions patients have when they set a goal to lose weight. Educators need to work with patients to help them develop a realistic approach to weight loss that is consistent with their diabetes management goals.
Anti-Diabetes and Anti-Obesity Medications: Effects on Weight in People With Diabetes
Authors: Hollander Priscilla
Published: August 2007

In Brief

Choosing medications for people with diabetes involves consideration of a number of factors, including effects on weight. Improvements in glucose control are often linked to weight gain, but this does not have to be the inevitable result of diabetes treatment. Adding a drug that either promotes weight-loss or is weight neutral to one that promotes weight gain and providing medical nutrition therapy can be considered.
Insulin-Related Knowledge Among Health Care Professionals in Internal Medicine
Authors: Derr Rachel L. , Sivanandy Mala S. , Bronich-Hall Lauren , Rodriguez Annabelle
Published: August 2007

Background. Inpatient diabetes treatment has become more complicated recently with the introduction of new insulin formulations and a new emphasis on tight blood glucose control. Insufficient knowledge of insulin contributes to errors in its use that may cause adverse patient outcomes.

Methods. Seventy-three faculty members, 113 residents, and 191 nurses from four hospitals completed a 20-item multiple-choice questionnaire that assessed knowledge of insulin nomenclature and characteristics and inpatient insulin use.

Results. The percentage of knowledge-based questions answered correctly was low: 51% for faculty, 59% for house staff, and 47% for nurses. Scores on questions testing knowledge of insulin nomenclature and characteristics were similar to scores on those addressing inpatient insulin use among faculty and house staff; however, nurses scored better on the former than the latter (60 vs. 34%, P < 0.0001). Knowledge of names and characteristics of newer insulins, such as glargine, aspart, and lispro, was poor compared to knowledge of older insulin formulations among all professional categories (46 vs. 78%, P < 0.0001). House staff performed better than faculty (62 vs. 49%, P = 0.09) and nurses (62 vs. 34%, P < 0.0001) on questions regarding inpatient diabetes management, but all groups frequently missed questions involving sliding-scale insulin use and dosing insulin in patients with type 1 diabetes.

Conclusion. Educational programs teaching insulin characteristics and inpatient diabetes management are needed for all categories of health care providers. Increased knowledge may help to improve patient safety in the hospital.
Globalization, “Glocal” Development, and Teachers’ Work: A Research Agenda
Authors: Weber Everard
Published: August 2007

The author discusses the evolution of ideas about the relationship between national and international development and educational change since World War II. He critically reviews relevant literature in comparative and international education, focusing on the concept of teachers’ work. The analyses draw on theories of postcolonialism. The author argues that virtually without exception, studies of, and theories about, teaching as work are based on the experiences of the northern hemisphere, particularly developed countries. He calls for qualitative methodologies and fieldwork to analyze teaching and teaching as work in modern South Africa and other subaltern countries. The research agenda seeks to revise existing notions of teachers’ work emphasizing conditions in industrialized countries and to interrogate their utility given the profoundly different conditions in developing countries. It also seeks to make problematic conventional understandings of globalization and glocal development, arguing that these too should be revised given empirical data on teachers and teaching in poor countries.
Race, School Achievement, and Educational Inequality: Toward a Student-Based Inquiry Perspective
Authors: Wiggan Greg
Published: August 2007

Over the past four decades, there have been numerous discussions on student achievement and school failure. Within this time, the debate over the causes and consequences of racial differences in achievement has been at the heart of the nation’s social and political life. The author discusses the major developments in achievement research over the past century and examines the foremost explanations given for racial differences in school performance, namely, genetic deficiency, social class and cultural poverty, low teacher expectancy, and student oppositional identity. The article addresses the strengths and limitations of the existing body of work and concludes with directions toward a student-based inquiry approach to achievement research aimed at filling in some of the missing information in the literature.
Enzymatic Activity of Human Carboxylesterases
Authors: Ross Matthew K. , Borazjani Abdolsamad
Published: August 2007

The carboxylesterases (CEs) are hydrolytic enzymes that metabolize xenobiotics that contain ester, thioester, or amide bonds. CEs are ubiquitously expressed but are found in highest concentration in membrane‐enriched fractions of the liver. This unit describes assays used to measure the enzymatic activity and tissue distribution of human CEs. Both spectrophotometric and HPLC‐based assays are described in detail. Several of these methods are rapid and easy to perform. These methods will be useful to investigators who are interested in studying the metabolism and disposition of esterified drugs and environmental chemicals. Curr. Protoc. Toxicol. 33:4.24.1‐4.24.14. © 2007 by John Wiley & Sons, Inc.
Techniques for Mammalian Cell Tissue Culture
Authors: Phelan Mary C.
Published: August 2007

This appendix opens with detailed discussions on the latest principles of sterile technique and preparation of culture media. Step‐by‐step protocols describe trypsinizing and subculturing monolayer cultures, passaging suspension cultures, freezing and thawing cells, counting cells using a hemacytometer, and preparing cells for transport.Curr. Protoc. Toxicol. 33:A.3B.1‐A.3B.18. © 2007 by John Wiley & Sons, Inc.
Detection of Protein‐Protein Interactions by Coprecipitation
Authors: Elion Elaine A.
Published: August 2007

Co‐precipitation of proteins from whole cell extracts is a valuable approach to test for physical interactions between proteins of interest. It may be the method of choice, or may be used in conjunction with other procedures to detect protein‐protein interactions, such as two‐hybrid analyis and co‐purification schemes, and tests of physical associations using purified proteins. Curr. Protoc. Protein Sci. 49:19.4.1‐19.4.10. © 2007 by John Wiley & Sons, Inc.
Proteomic Identification of Cellular Protease Substrates Using Isobaric Tags for Relative and Absolute Quantification (iTRAQ)
Authors: Dean Richard A. , Smith Derek , Overall Christopher M.
Published: August 2007

Identification of protease substrates is essential to identify and understand the functional consequences of normal and dysregulated proteolysis in disease on the proteome. Isobaric tags for relative and absolute quantification (iTRAQ) can be used to identify novel protease substrates in the cellular context. An amine‐targeted iTRAQ tag labels tryptic peptides generated from the proteins and protease cleavage products of secreted proteins, as well as protein domains shed from the cell membrane or pericellular matrix of protease‐transfected cells that have accumulated in conditioned medium; a second iTRAQ tag is used for control cells. MS/MS fragmentation enables sequencing of the pooled pairs of differently labeled but identical peptides and generates a low mass signature ion peak unique for each label. This signature ion peak identifies the peptides originating from the protease‐transfected or control cells; comparison of the peak areas enables relative quantitation of the peptide between the samples. Curr. Protoc. Protein Sci. 49:21.18.1‐21.18.12. © 2007 by John Wiley & Sons, Inc.
The CLIP‐CHIP Oligonucleotide Microarray: Dedicated Array for Analysis of All Protease, Nonproteolytic Homolog, and Inhibitor Gene Transcripts in Human and Mouse
Authors: Kappelhoff Reinhild , Overall Chris
Published: August 2007

The CLIP‐CHIP oligonucleotide microarray allows the analysis of mRNA transcript levels in a tissue sample for all proteases, nonproteolytic homologs, and protease inhibitors of the human and mouse genome. In the protocol presented in this unit, total RNA is extracted from a tissue, and the resulting mRNA is reverse transcribed into cDNA and dsDNA and then amplified in an in vitro transcription reaction. The amplified antisense RNA is labeled with a fluorescent dye and hybridized to the CLIP‐CHIP, which contains unique oligonucleotides that are specifically designed for the protease, nonproteolytic homologs, protease inhibitors, and control samples. After hybridization, the fluorescence intensity of each spot is measured, thus identifying mRNA transcripts that are expressed and allowing basic quantification of expressed transcripts. Curr. Protoc. Protein Sci. 49:21.19.1‐21.19.16. © 2007 by John Wiley & Sons, Inc.
Overview of Tandem Mass Spectrometry (MS/MS) Database Search Algorithms
Authors: Kapp Eugene , Schütz Frédéric
Published: August 2007

Mass spectrometry–based methods for the identification of proteins are fundamental platform technologies for proteomics. One comprehensive approach is to subject trypsinized peptides to tandem mass spectrometry (MS/MS) to obtain detailed structural information. Different strategies are available for interpreting MS/MS data and hence deducing the amino acid sequence of the peptides. The most common method is to use a search algorithm to identify peptides by correlating experimental and theoretical MS/MS data (the latter being generated from possible peptides in the protein sequence database). Identified peptides are collated and protein entries from the sequence database inferred. This unit focuses on the most widely used tandem MS peptide identification search algorithms (commercial and open source), their availability, ease of use, strengths, speed and scoring, as well as their relative sensitivity and specificity. Curr. Protoc. Protein Sci. 49:25.2.1‐25.2.19. © 2007 by John Wiley & Sons, Inc.
Experimental Autoimmune Thyroiditis in the Mouse
Authors: Kong Yi‐chi M.
Published: August 2007

Experimental autoimmune thyroiditis (EAT) in mice is an excellent model for Hashimoto's thyroiditis (HT). It is induced with thyroglobulin (Tg), a known thyroid autoantigen that is common to both mouse and human and for which several conserved, thyroiditogenic epitopes have been identified. This unit describes induction and evaluation of EAT using thyroid histology and in vitro proliferative response assays. An ELISA is presented to detect the level of antibody to mouse thyroglobulin (MTg). To induce EAT, either bacterial lipopolysaccharide (LPS) or supplemented complete Freund's adjuvant (CFA) can be used as adjuvant. A support protocol for preparing MTg is included. The T cell proliferation assay can be used to examine the antigenicity of synthetic peptides derived from MTg or heterologous Tg. EAT can be adoptively transferred utilizing cells that have been expanded in vitro, as described. A protocol is provided for inducing tolerance using deaggregated MTg; induction of tolerance requires larger amounts of MTg but efficiently suppresses EAT development. Also included is a protocol to demonstrate the role of regulatory T cells in mediating tolerance. A protocol to delineate HLA association with HT is illustrated using HLA class II transgenic mice. Curr. Protoc. Immunol. 78:15.7.1‐15.7.21. © 2007 by John Wiley & Sons, Inc.
Cloning (The Story of Dolly the Sheep)
Authors: Love Jamie
Published: August 2007

The Cell Cycle

The Early Stages of Embryology
Stardust
Mission
Authors:   Jet Propulsion Laboratory
Published: August 2007

NASA
's Discovery Program

Why Stardust?

Comets

Other Comet Missions

Interstellar Dust

Mission Overview

Spacecraft Profile

Aerogel Dust Collectors

Sample Return Capsule

Comet and Interstellar Dust Analyzer

Dust Flux Monitor

Navigation Camera

Propulsion System

Attitude Control

Command and Data Handling

Power

Thermal Control

Telecommunications

Redundancy

Whipple Shields
Laboratory Maintenance of Mycobacterium tuberculosis
Authors: Larsen Michelle H. , Biermann Karolin , Jacobs, William R.
Published: August 2007

This unit includes protocols for the laboratory maintenance of Mycobacterium tuberculosis, including growth on liquid and solid media as well as recommendations for long‐term strain storage. Considerations for working with M. tuberculosis at Biosafety Level 3 containment are also discussed. Curr. Protoc. Microbiol. 6:10A.1.1‐10A.1.8. © 2007 by John Wiley & Sons, Inc.
Genetic Manipulation of Mycobacterium tuberculosis
Authors: Larsen Michelle H. , Biermann Karolin , Tandberg Steven , Hsu Tsugunda , Jacobs, William R.
Published: August 2007

This unit includes protocols for the genetic manipulation of Mycobacterium tuberculosis, including nucleic acid extraction (plasmid DNA, genomic DNA, and mRNA), and methods for electroporation (transformation), transduction (including allelic exchange), and transposon mutagenesis. Considerations for working with M. tuberculosis at Biosafety Level 3 containment are also discussed. Curr. Protoc. Microbiol. 6:10A.2.1‐10A.2.21. © 2007 by John Wiley & Sons, Inc.
Making instructional animations more effective: a cognitive load approach
Authors: Ayres Paul , Paas Fred
Published: August 2007

This themed issue consists of seven empirical papers, as well as an introduction and discussion, and has its genesis in three symposia, organised by the authors of this article and presented at the 2006 Annual Meeting of the American Educational Research Association (AERA) in San Francisco, California. The papers investigate a number of conditions under which instructional animations may be effective. This article uses cognitive load theory (CLT) to provide an explanation for why animated instructions have not currently produced the learning benefits expected. A brief overview of the papers with a focus on how they accommodate critical aspects of cognitive load is given. The issue finishes with a discussion on each paper and identifies some common principles and recommendations for instructional design and research into animations. Copyright © 2007 John Wiley & Sons, Ltd.
Attention cueing as a means to enhance learning from an animation
Authors: de Koning Björn B. , Tabbers Huib K. , Rikers Remy M. J. P. , Paas Fred
Published: August 2007

The question how animations should be designed so that learning is optimised, is still under discussion. Animations are often cognitively very demanding, resulting in decreased learning outcomes. In this study, we tried to prevent cognitive overload and foster learning by focusing the learners' attention to one element (i.e. process) of an animation using a cueing technique. Psychology students viewed an animation of the cardiovascular system and were subsequently given a comprehension test and a transfer test. One group studied the animation without a visual cue, while for another group a visual cue was added to the animation. Results indicated that cueing not only enhanced comprehension and transfer performance for cued information, but also for uncued information. It is concluded that cueing can be used as a technique to improve learning from an animation. Results are interpreted in terms of cognitive load theory (CLT). Copyright © 2007 John Wiley & Sons, Ltd.
Animated pedagogical agents: does their degree of embodiment impact learning from static or animated worked examples?
Authors: Lusk Mary Margaret , Atkinson Robert K.
Published: August 2007

This study examined the impact of varying an animated pedagogical agent's level of embodiment in a learning environment consisting of static or animated multimodal worked examples illustrating how to solve multi‐step proportional word problems. In the fully embodied condition, the agent was programmed to coordinate spoken instructional explanations with non‐verbal forms of communication (locomotion, gesture, and gaze) to support learning. In the minimally embodied condition, the same agent provided the spoken instructions but remained static on the screen. In the voice‐only condition, the spoken instructions were provided without an agent. Of the 174 college‐age participants, those provided with the fully embodied agent produced more conceptually accurate answers to near and far transfer items than their counterparts in the voice‐only condition. Moreover, participants that studied animated worked examples, where the problem's subgoals were presented sequentially over time, outperformed their peers provided with static examples with simultaneously‐presented subgoals on measures of transfer. Copyright © 2007 John Wiley & Sons, Ltd.
Optimising learning from animations by minimising cognitive load: cognitive and affective consequences of signalling and segmentation methods
Authors: Moreno Roxana
Published: August 2007

Prospective teachers learned about seven teaching skills either with or without (control group) an exemplar classroom video (Experiment 1) or animation (Experiment 2) showing how an expert teacher applied such skills. It was hypothesised that directing attention to relevant dynamic information with signalling (SI) and/or segmenting (SE) the video/animation into smaller chunks of information would facilitate students' learning. Across both experiments, the control group outperformed SI and SE groups on retention of the theoretical information but underperformed most video/animation groups when asked to evaluate and apply teaching skills to a classroom scenario. SE groups outperformed no‐SE groups on all learning measures and reported lower levels of cognitive load. The findings encourage segmenting instructional videos and animations into small chunks to help novice students learn from complex dynamic visualisations. Copyright © 2007 John Wiley & Sons, Ltd.
Instructional efficiency of animation: effects of interactivity through mental reconstruction of static key frames
Authors: Paas Fred , Van Gerven Pascal W. M. , Wouters Pieter
Published: August 2007

This study used cognitive load theory to investigate whether an animation about the cardiovascular system can become a more effective educational tool by designing it with sensitivity to the capacity limitations of working memory. To manage the high extraneous cognitive load imposed by the need to process series of successive and transient information elements, a sequence of static key frames from the animation was presented to learners directly after the animation. Two interactive instructional conditions, which required learners either to construct or reconstruct the sequence of key frames, were compared to a non‐interactive condition. It was hypothesised that the interactive activities would lead to more efficient transfer performance. The results confirmed the hypothesis, indicating that the interactive conditions required less mental effort to attain the same performance as the non‐interactive condition. Instructional design implications for learning from animations are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Creating retroactive and proactive interference in multimedia learning
Authors: Mayer Richard E. , DeLeeuw Krista E. , Ayres Paul
Published: August 2007

When students learn how a physical system works, does it help if they also learn how similar systems work? Some college students (concise group) studied a multimedia lesson that explained how hydraulic brakes work, consisting of narrated animation or annotated illustrations. Others (expanded group) received the same lesson along with multimedia explanations of caliper brakes and air brakes presented either after (Experiment 1) or before (Experiment 2) the explanation of hydraulic brakes. Across the combined experiments, students performed worse on retention (d = 0.37) and transfer tests (d = 0.30) concerning hydraulic brakes if the lesson also contained lessons on caliper and air brakes; within each experiment, the effects were statistically significant in Experiment 1 (d = 0.57 and 0.53, respectively) but not in Experiment 2 (d = 0.23 and 0.17, respectively). Students performed similarly with narrated animations and annotated illustrations. These results suggest that if students are expected to learn about a specific system, using examples about related systems can depress learning, particularly in the form of retroactive interference (in Experiment 1). These results extend the coherence principle, that is, the idea that adding extra material to an explanation can interfere with learning. There was no evidence to support converting static graphics into animation. Copyright © 2007 John Wiley & Sons, Ltd.
Non‐Hydrothermal Synthesis of 1D Nanostructured Manganese‐Based Oxides: Effect of Cation Substitution on the Electrochemical Performance of Nanowires
Authors: Park D. H. , Lee S.‐H. , Kim T. W. , Lim S. T. , Hwang S.‐J. , Yoon Y. S. , Lee Y.‐H. , Choy J.‐H.
Published: August 2007

The synthesis of cation‐substituted 1D manganese oxide nanowires is achieved via a non‐hydrothermal oxidation reaction using a solid‐state precursor and conventional glassware. By changing the reaction conditions and precursor composition, it is possible to control the crystal structure and chemical composition of the resulting 1D nanostructured materials. The nanowires are found to exhibit promising electrochemical properties as cathode materials in lithium secondary batteries; moreover, the electrochemical properties of the nanowires can be improved by the partial replacement of Mn with Cr3+ cations. The measurements strongly suggest that the cation composition of the nanostructured metal oxides is very important for optimizing their electrode performance. The non‐hydrothermal solution synthesis method presented here provides an effective composition‐tailored approach for the fabrication of large quantities of 1D manganese oxide nanowires.
A Molecular Glass for Deep‐Blue Organic Light‐Emitting Diodes Comprising a 9,9′‐Spirobifluorene Core and Peripheral Carbazole Groups
Authors: Tang S. , Liu M. R. , Lu P. , Xia H. , Li M. , Xie Z. Q. , Shen F. Z. , Gu C. , Wang H. P. , Yang B. , Ma Y. G.
Published: August 2007

Novel fluorene‐based compounds, TCPC‐6 and TCPC‐4, with rigid central spirobifluorene cores and peripheral carbazole groups are synthesized using the Suzuki coupling reaction. The optical, electrochemical, and thermal properties of these compounds are characterized. The compounds show strong deep‐blue emission both in solution and as thin films. Both TCPC‐6 and TCPC‐4 exhibit amorphous morphologies in the solid state with high glass transition temperatures (Tg) of 108 and 143 °C, respectively. Atomic force microscopy (AFM) measurements indicate that high‐quality amorphous films of these novel compounds can be prepared by spin‐coating. The oxidation potentials of TCPC‐6 and TCPC‐4 are significant lower than that of model compounds without peripheral carbazole groups, which suggests that these compounds have relatively high highest occupied molecular orbital (HOMO) energy levels and better hole‐injection capabilities. Light‐emitting devices fabricated by spin‐coating films of these molecules exhibit deep‐blue emission with Commission Internationale de l'Eclairage (CIE) chromaticity coordinates (x, y) of (0.16, 0.05); the devices fabricated using spin‐coated TCPC‐6 and TCPC‐4 layers exhibit high luminance efficiencies of 1.35 and 0.90 cd A–1 (with external quantum efficiencies of 3.72 and 2.47 %), respectively.
Mineral Deposition and Crystal Growth in the Continuously Forming Teeth of Sea Urchins
Authors: Ma Y. R. , Weiner S. , Addadi L.
Published: August 2007

The early stages of formation of the crystalline elements in the continuously forming sea urchin teeth were studied using polarized light microscopy, SEM, TEM and calcite overgrowth. Transient amorphous calcium carbonate (ACC) is initially deposited in the needles and subsequently transforms into a single crystal of calcite. ACC exists in the center of both the primary plates and the needles, even though the surfaces are already well crystallized. TEM images and electron diffraction patterns, as well as calcite crystal overgrowth shows that the highly convoluted primary plate‐lamellar needle complex grows into a single crystal of calcite. The calcite crystal c axis is approximately parallel to the slightly curved surface of the primary plate. The needles grow along the unusual [102] direction of calcite. This study demonstrates that highly complex shaped single crystals are produced using a transient amorphous precursor phase. The beneficial properties of the single crystals are then combined with those of a polycrystalline matrix to yield a sophisticated composite functional material. This strategy could conceivably be applied to the production of synthetic materials.
Neuropathy as a presenting feature in fragile X‐associated tremor/ataxia syndrome
Authors: Hagerman Randi J. , Coffey Sarah M. , Maselli Ricardo , Soontarapornchai Kultida , Brunberg James A. , Leehey Maureen A. , Zhang Lin , Gane Louise W. , Fenton‐Farrell Grace , Tassone Flora , Hagerman Paul J.
Published: August 2007

Peripheral neuropathy is common among patients with fragile X‐associated tremor ataxia syndrome (FXTAS). Four patients with FXTAS are described with neuropathy as the presenting feature, two having received a prior diagnosis of Charcot‐Marie‐Tooth (CMT) disease. A fifth is described with neuropathy as the only clinical feature. A functional connection between FXTAS and neuropathy has been suggested by the presence of lamin A/C in the intranuclear, neuronal and astrocytic inclusions of FXTAS, since mutations in lamin A/C are known to give rise to an axonal form of CMT. © 2007 Wiley‐Liss, Inc.
Neuronal LR11/sorLA expression is reduced in mild cognitive impairment
Authors: Sager Kristen L. , Wuu Joanne , Leurgans Susan E. , Rees Howard D. , Gearing Marla , Mufson Elliott J. , Levey Allan I. , Lah James J.
Published: August 2007

Objective

LR11 (aka sorLA) is a multifunctional neuronal receptor that binds apolipoprotein E and interacts with amyloid precursor protein to regulate amyloidogenesis. Reduced expression of LR11, as occurs in the brains of individuals with Alzheimer's disease (AD), increases amyloidogenesis, and variants in the gene that encodes LR11, SORL1, have recently been linked to risk for late‐onset AD. In this study, we sought to determine whether reduced expression of LR11 occurs early in the disease process and whether protein levels in cortical neurons are associated with clinical and pathological changes in mild cognitive impairment (MCI), a condition that may represent prodromal AD.

Methods

A novel quantitative immunohistochemical approach was used to measure LR11 levels in brain tissue collected from subjects diagnosed antemortem with either no cognitive impairment, MCI, or AD from the Rush University Religious Orders Study.

Results

LR11 levels in MCI were intermediate between no cognitive impairment and AD. LR11 expression was heterogeneous in MCI, forming low‐ and high‐level LR11 subgroups. MCI subjects with low LR11 were significantly more cognitively impaired than the high LR11 subjects. We also found a significant correlation between cognitive performance and LR11 levels across all clinical groups examined. There was no association between LR11 and plaque and tangle pathology.

Interpretation

Neuronal LR11 levels are reduced in prodomal AD. The correlation between LR11 expression and cognitive performance indicates that reduced LR11 levels reflect disease severity and may predict progression to AD in a subgroup of individuals with MCI. Ann Neurol 2007
Design guidelines for using distillation simulation software in the field
Authors: Kolmetz Karl , Mardikar Asit , Gulati Harpreet , Kiong Ng Wai , Yee (Ron) Lim Tau , Cheah Phaik Sim
Published: August 2007

Process simulation is a powerful chemical engineering tool that has widespread use in the chemical processing industry. If used correctly, it can help design, optimize and troubleshoot process units, when you follow the guidelines developed from the fundamental basics of chemical engineering. It is important to remember that computer hardware advancements have only improved the speed of the calculation. Despite rapid progress in computational speed and user‐friendly interfaces, understanding the rules and limitations of simulation tools is still a prerequisite to obtain simulated results close to those measured in the field. The engineer must supply the correct input data, interpret errors that occurred and make critical judgment on the results. Mastering these techniques often requires substantial field experience and practice.

Accumulating such knowledge in the form of design guidelines helps young engineers to ramp up their learning curves. Working steps like correct selection of actual field efficiencies, choosing appropriate vapor and liquid equilibrium (VLE) methods, feed characterization and analysis of actual hydraulic behavior, have a strong influence on the accuracy of the model's results. Developing guidelines for each of these steps is very important to a practicing engineer. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.
FTIR study of ageing epoxy resin reinforced by reactive graphitic nanofibers
Authors: Jana Soumen , Zhong Wei‐Hong
Published: August 2007

We previously developed a novel modified epoxy matrix for macrocomposites using reactive graphitic nanofibers (r‐GNFs), which showed improved mechanical properties. This article is devoted to study the efficacy of the r‐GNFs against the damage due to exposition of the matrix to hygrothermal environment and UV radiation. Moisture sorption characteristics of the pure epoxy and nanoepoxy were investigated and all kinds of matrices showed similar absorption behavior. Both diffusion and relaxation processes in sorption were observed. DSC curves of nonaged specimens of all concentrations confirmed that samples were not fully cured and r‐GNFs lowered the curing degree. The effects of ageing were studied through the changes of molecular conformation by Fourier Transform infrared spectroscopy (FTIR). The results show that UV radiation assists in post‐curing of the matrices. Hydroxyl unit, carbonyl unit, and epoxide unit were chosen to study the degradation. It is observed that the degradation due to UV radiation is more severe compared with that due to hygrothermal expose. It also reveals that r‐GNFs resist the degradation of the epoxy resin; particularly, the nanoepoxy with 0.3 wt % of r‐GNFs has the highest ageing resistance, which is in agreement with our previously tested results of mechanical properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Directed evolution of novel protein functions
Authors: Zhao Huimin
Published: August 2007

Directed evolution has been successfully used to engineer proteins for basic and applied biological research. However, engineering of novel protein functions by directed evolution remains an overwhelming challenge. This challenge may come from the fact that multiple simultaneously or synergistic mutations are required for the creation of a novel protein function. Here we review the key developments in engineering of novel protein functions by using either directed evolution or a combined directed evolution and rational or computational design approach. Specific attention will be paid to a molecular evolution model for generation of novel proteins. The engineered novel proteins should not only broaden the range of applications of proteins but also provide new insights into protein structure–function relationship and protein evolution. Biotechnol. Bioeng. 2007;98: 313–317. © 2007 Wiley Periodicals, Inc.
Inferential non‐centred principal curve analysis of time‐intensity curves in sensory analysis: the methodology and its application to beer astringency evaluation
Authors: François Nancy , Govaerts Bernadette , Guyot‐Declerck C.
Published: August 2007

Improving technologies and better understanding of sensory phenomena have lead sensory analysts to develop statistical methods to assess sensations that endure over time (e.g. the bitterness or astringency of a beer) dynamically. The data produced by this type of experiment is classically a time‐intensity (TI) curve, and their analysis remains an active research topic. The classical approach, widely used in this context, starts by extracting some significant parameters from the initial curves (maximum intensity, area under the curve (AUC), etc.). Descriptive data analysis or statistical modelling is then applied to get information from these summary parameters. This paper presents a different method, called inferential non‐centred principal curve analysis (INCPCA), for the analysis of TI curves. It combines multivariate analysis (to visualise the curves in a space of smaller dimensions) with statistical modelling (aimed at enhancing the significance of factor effects). Non‐centred principal curves (NCPCs) are first extracted from the curves matrix. They decompose the TI curves into different interpretable components. Score plots are used to represent the projection of the initial curves in the space of the first principal curves and allow factors and judge effects to be visualised. Mixed modelling is then applied to test the significance of these effects using PCA scores as model responses. The classical and INCPCA methods are illustrated on a TI experiment exploring the relation between beer astringency and three factors of interest: pH, O2 content and aging. Eight beers arranged in a 23 factorial design were tested in triplicate by eight trained judges. Copyright © 2007 John Wiley & Sons, Ltd.
Geometry and a priori estimates for free boundary problems of the Euler's equation
Authors: Shatah Jalal , Zeng Chongchun
Published: August 2007

In this paper we derive estimates to the free boundary problem for the Euler equation with surface tension, and without surface tension provided the Rayleigh‐Taylor sign condition holds. We prove that as the surface tension tends to 0, when the Rayleigh‐Taylor condition is satisfied, solutions converge to the Euler flow with zero surface tension. © 2007 Wiley Periodicals, Inc.
High‐level distribution for the rapid production of robust telecoms software: comparing C++ and ERLANG
Authors: Nyström J. H. , Trinder P. W. , King D. J.
Published: August 2007

Currently most distributed telecoms software is engineered using low‐ and mid‐level distributed technologies, but there is a drive to use high‐level distribution. This paper reports the first systematic comparison of a high‐level distributed programming language in the context of substantial commercial products. Our research strategy is to reengineer some C++/CORBA telecoms applications in ERLANG, a high‐level distributed language, and make comparative measurements. Investigating the potential advantages of the high‐level ERLANG technology shows that two significant benefits are realized. Firstly, robust configurable systems are easily developed using the high‐level constructs for fault tolerance and distribution. The ERLANG code exhibits resilience: sustaining throughput at extreme loads and automatically recovering when load drops; availability: remaining available despite repeated and multiple failures; dynamic reconfigurability: with throughput scaling near‐linearly when resources are added or removed. Secondly, ERLANG delivers significant productivity and maintainability benefits: the ERLANG components are less than one‐third of the size of their C++ counterparts. The productivity gains are attributed to specific language features, for example, high‐level communication saves 22%, and automatic memory management saves 11%—compared with the C++ implementation. Investigating the feasibility of the high‐level ERLANG technology demonstrates that it fulfils several essential requirements. The requisite distributed functionality is readily specified, even although control of low‐level distributed coordination aspects is abrogated to the ERLANG implementation. At the expense of additional memory residency, excellent time performance is achieved, e.g. three times faster than the C++ implementation, due to ERLANG's lightweight processes. ERLANG interoperates at low cost with conventional technologies, allowing incremental reengineering of large distributed systems. The technology is available on the required hardware/operating system platforms, and is well supported. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and Characterization of Bis(dithiolene) Tungsten(VI), ‐(V), and ‐(IV) Complexes and Their Reactivities in Coupled Electron–Proton Transfer: A New Series of Active Site Models of Tungstoenzymes
Authors: Sugimoto Hideki , Tarumizu Makoto , Miyake Hiroyuki , Tsukube Hiroshi
Published: August 2007

New tungsten(VI), ‐(V), and ‐(IV) complexes containing 3,6‐dichloro‐1,2‐benzenedithiolate (bdtCl2), (Et4N)2[WVIO2(bdtCl2)2] {(Et4N)2[1]}, (Et4N)[WVO(bdtCl2)2] {(Et4N)[2]}, and (Et4N)2[WIVO(bdtCl2)2] {(Et4N)2[3]} were synthesized and characterized as active site models of tungstoenzymes.(Et4N)2[1] was prepared in high yield by the reaction of WO2Cl2 with 2bdtCl2 at low temperature, and its crystal structure was determined. Isomerization between octahedral structures (Δ and Λ forms) of the tungsten center of(Bu4N)2[1] was characterized by variable‐temperature 1H NMR (VT 1H NMR) spectral analysis, which offers the first example of six‐coordinate bis(dithiolene) tungsten(VI) complexes. The isomerization of the molybdenum center of (Bu4N)2[MoVIO2(bdtCl2)2] {(Bu4N)2[4]} was similarly characterized. A comparison of their activation energies indicated that the tungsten center underwent slower isomerization than that of the molybdenum one. (Et4N)2[1] underwent an irreversible reduction at –2.1 V vs. SCE in CH3CN by a coupled electron–proton transfer (CEPT) process to yield(Et4N)2[3], while (Et4N)2[3] underwent an irreversible oxidation by a CEPT process at –0.27 V in the presence of 2 equiv. of Et4NOH in CH3CN to yield (Et4N)2[1]. (Et4N)[2] disproportionated into 0.5 equiv. of (Et4N)2[1] and 0.5 equiv. of (Et4N)2[3] when treated with 1 equiv. of Et4NOH in CH3CN.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Determination of Traces of Cobalt in Zinc Matrix by Catalytic Adsorptive Stripping Voltammetry at Bismuth Film Electrode
Authors: Korolczuk Mieczyslaw , Grabarczyk Małgorzata , Moroziewicz Aleksandra
Published: August 2007

An catalytic adsorptive stripping voltammetric procedure for the determination of cobalt in a zinc matrix at an in situ plated bismuth film electrode was described. The procedure exploits the enhancement effect of a cobalt peak observed in the system Co(II)–dimethylglyoxime–piperazine‐1,4‐bis(2‐ethanesulfonic acid)–cetyltrimethylammonium bromide. Using optimized conditions, in a solution containing 0.01 mol L−1 Zn(II) the calibration plot for Co(II) following accumulation time of 120 s was linear from 2×10−10 to 5×10−8 mol L−1. The detection limit (based on 3σ criterion) for Co(II) of 6×10−11 mol L−1 was achieved. The proposed procedure was applied for Co(II) determination in zinc reagent for analysis and in tap water.
The Effect of the Closely‐Spaced Working and Auxiliary Electrodes on the Performance of Electrochemical Oxygen Sensor
Authors: Wu Jian , Ye Zunzhong , Ying Yibin , Ji Feng
Published: August 2007

In this paper the influence of the electrochemical reaction at the auxiliary electrode of oxygen microsensors on the sensor performance was investigated. When the auxiliary electrode is closely spaced to the working electrode, the redox cycling of O2/H2O takes place in an electrochemical oxygen sensor. This cycling alters the oxygen distribution around the working electrode and therefore affects the measured cathodic current passing through the working electrode. Calibrations have to be taken out to determine the real O2/H2O cycling effects. Furthermore, this redox cycling also provides the possibility to enhance the sensitivity of the electrochemical oxygen microsensor. Experimental results indicate that the sensitivity of the oxygen sensor is enhanced 3.0 times with the on‐chip 10 μm spaced interdigitated auxiliary electrode.
Work‐related physical activity and the risk of dementia and Alzheimer's disease
Authors: Rovio Suvi , Kåreholt Ingemar , Viitanen Matti , Winblad Bengt , Tuomilehto Jaakko , Soininen Hilkka , Nissinen Aulikki , Kivipelto Miia
Published: August 2007

Background

Leisure‐time physical activity has been related with a reduced risk of dementia and Alzheimer's disease (AD). The effects of occupational and commuting physical activity (physical activity at work and on the way to work) on cognitive health are still unclear. This study aimed to clarify the association between work‐related physical activity and dementia/AD.

Methods

Participants of the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study were derived from random, population‐based samples previously studied in a survey carried out in 1972, 1977, 1982, or 1987. After an average follow‐up of 21 years, 1449 individuals (73%) aged 65 to 79 years participated in the re‐examination in 1998.

Results

Neither occupational [Odds Ratio (OR) 1.45; 95% Confidence Intervals (CI) 0.66–3.17] nor commuting physical activity (OR 0.46; 95% CI 0.10–2.17) were associated with the risk of dementia or AD after adjustments for age, sex, education, follow‐up time, locomotor symptoms, main occupation during life, income at midlife, leisure‐time physical activity, other subtype of work‐related physical activity, ApoE genotype, vascular disorders and the smoking status. There were also no interactions between work‐related physical activity and the ApoE ε4 genotype, leisure‐time physical activity or sex.

Conclusions

In this study, work‐related physical activity was not found to be sufficient to protect against dementia and AD later in life. The lack of effect might be partly due to a residual confounding. Nevertheless, physical activity during leisure‐time may be beneficial even for people who are physically active at work or when commuting. Copyright © 2007 John Wiley & Sons, Ltd.
A mass‐balance approach to estimate in‐stream processes in a large river
Authors: Teissier Samuel , Sauvage Sabine , Vervier Philippe , Garabétian Frédéric , Sánchez‐Pérez José‐Miguel
Published: August 2007

A mass‐balance approach was used to estimate in‐stream processes related to inorganic nitrogen species (NH4+, NO2− and NO3−) in a large river characterized by highly variable hydrological conditions, the Garonne River (south‐west France). Studies were conducted in two consecutive reaches of 30 km located downstream of the Toulouse agglomeration (population 760 000, seventh order), impacted by modification of discharge regime and high nitrogen concentrations. The mass‐balance was calculated by two methods: the first is based on a variable residence time (VRT) simulated by a one‐dimensional (1‐D) hydraulic model; the second is a based on a calculation using constant residence time (CRT) evaluated according to hydrographic peaks. In the context of the study, removal of dissolved inorganic nitrogen (DIN) for a reach of 30 km is underestimated by 11% with the CRT method. In sub‐reaches, the discrepancy between the two methods led to a 50% overestimation of DIN removal in the upper reach (13 km) and a 43% underestimation in the lower reach (17 km) using the CRT method. The study highlights the importance of residence time determination when using modelling approaches in the assessment of whole stream processes in short‐duration mass‐balance for a large river under variable hydrological conditions. Copyright © 2007 John Wiley & Sons, Ltd.