bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk factors for secondary proctectomy in patients with familial adenomatous polyposis
Authors: Sinha A , Tekkis P P , Rashid S , Phillips R K S , Clark S K
Published: July 2010

Background

Colectomy and ileorectal anastomosis (IRA) or restorative proctocolectomy are performed for prophylaxis in familial adenomatous polyposis (FAP). After IRA patients may require secondary proctectomy for worsening polyposis or rectal cancer. Outcomes after IRA were evaluated and risk factors predictive of progressive rectal disease identified.

Methods

Parametric survival analysis was used to identify predictors of progressive rectal disease in all patients undergoing an IRA for FAP at a single centre. Hazard ratios (HRs) were calculated for phenotype, genotype, sex, age at surgery and presence of colonic cancer.

Results

Of 427 patients who underwent IRA, 48 (11·2 per cent) developed rectal cancer and 77 (18·0 per cent) required proctectomy for worsening polyposis over a median follow-up of 15 (range 7–25) years. By the age of 60 years half of the patients retained their rectum. Rectal polyp count exceeding 20 (HR 30·99, 95 per cent confidence interval 9·57 to 100·32; P < 0·001), APC mutation codon 1250–1450 (HR 3·91, 1·45 to 10·51; P = 0·007), colonic polyp count 500 or more (HR 2·18, 1·24 to 3·82; P = 0·006) and age less than 25 years at the time of surgery (HR 1·99, 1·17 to 3·37; P = 0·011) were independent predictors of progressive rectal disease.

Conclusion

The risk of proctectomy after IRA for FAP is based on patient genotype, phenotype and age at surgery.
Evaluation of HPSEC‐ELSD method for precise measurement of β‐agarase activity
Authors: Kazłowski Bartosz , Kazłowska Katarzyna , Pan Chorng Liang , Ko Yuan Tih
Published: July 2010

β‐Agarase activity was monitored by traditional reducing sugar content methods: Somogyi–Nelson's arsenomolybdate, Miller's dinitrosalicylic acid and Kidby and Davidson's ferricyanide methods, as well as by high‐performance size exclusion chromatography coupled with a refractive index detector and an evaporative light scattering detector (ELSD). Calibration curves were established separately for each method to measure the amounts of the neoagaro‐oligosaccharides (NAOS) in the reaction mixtures, which are the products from 1–10 units (U) of β‐agarase cleavage activity on agarose. Product quantities from each monitoring method were compared with the isolated NAOS products. The graphs plotted by agarase activity unit and product concentration clearly displayed that the ELSD method closely followed the results of the isolated products. The percentage deviation of results measured by the five methods away from those of the isolated NAOS product mixture amounted to −13.1–35.1, −21.1–25.5, −27.1–23.81, 6.1–24.3 and 16.2–22.8%, respectively. When the loss during product isolation, about 15–17%, was taken into account, the high precision of the ELSD method was confirmed. HPSEC‐ELSD methods also accurately measured the enzyme kinetics as well as enabling partial identification of oligosaccharides assembled in the NAOS product mixture. This study established the HPSEC‐ELSD system as an alternative method for monitoring agarase activity. Copyright © 2010 John Wiley & Sons, Ltd.
One‐Pot Preparation of Imines from Nitroarenes by a Tandem Process with an Ir–Pd Heterodimetallic Catalyst
Authors: Zanardi Alessandro , Mata Jose A. , Peris Eduardo
Published: July 2010

A new tandem catalytic process has been studied for a heterodimetallic complex containing both iridium and palladium fragments connected by a 1,2,4‐trimethyltriazolyldiylidene ligand. The process implies the unprecedented preparation of imines from the direct reaction of nitroarenes and primary alcohols. The global process comprises the following steps: 1) reduction of the nitroarene to an amine, 2) oxidation of the alcohol to aldehyde, and 3) condensation of the aldehyde and the amine to form the corresponding imine. The oxidation of the alcohol to aldehyde is promoted by the iridium fragment, while the reduction of the nitro group to amine is facilitated by palladium. A wide set of different catalytic systems has been studied, showing that the Ir/Pd complex 1 is a highly active and stable catalyst in the preparation of imines.
Untersuchungen zur Herstellung von Bioethanol und Biogas aus Lignocelluloserohstoffen nach Vorbehandlung mit Steam Explosion und Cellulasen
Authors: Lindorfer J. , Steinmüller H. , Auer W. , Nidetzky B. , Loncar E. , Jäger A. , Eder A. , Hofer B.
Published: July 2010

Biotreibstoffe der zweiten Generation wie aus Lignocelluloserohstoffen hergestelltes Bioethanol stehen als Option gegen zunehmende Treibhausgasemissionen im Verkehrssektor hoch im Kurs. Zur Entwicklung eines wettbewerbsfähigen Herstellungsverfahrens wurden Versuche zur thermisch‐mechanischen Vorbehandlung (Steam Explosion), Cellulaseproduktion auf vorbehandeltem Rohstoff, enzymatischer Hydrolyse und Ethanol‐ sowie Biogasgärversuche auf dem generierten Weizenstrohhydrolysat im Labormaßstab durchgeführt.
Enhancement of Limestone Defluoridation of Water by Acetic and Citric Acids in Fixed Bed Reactor
Authors: Nath Suresh K. , Dutta Robin K.
Published: July 2010

Limestone defluoridation by fixed bed reactor has been studied with water pre‐acidified with edible organic acids, viz. acetic acid (AA) and citric acid (CA). The study has been carried out by varying acid concentration, contact time (t), number of repeated use of the same limestone bed (n), and chip size of the crushed limestone using fixed fluoride concentration of 10 mg/L in distilled water and groundwater amended to that concentration of fluoride. The presence of both the acids considerably improved the fluoride removal and the removal increased with increase in the acid concentration. Fluoride removal to less than 0.5 and 1.0 mg/L from initial 5 and 10 mg/L, respectively, have been achieved by the method on treatment with single reactor. The mechanism of fluoride removal in the process thought to be the increase in Ca2+activity by dissolution of limestone, which precipitates as CaF2. XPS analysis reveals that adsorption also contribute to the fluoride removal along with precipitation. The final pH of water remained within acceptable range for drinking water. Initial concentration of fluoride, effects the removal ability of the limestone particles only to some extent. The influence of other anions on fluoride removal process has a little influence which follows the order phosphate > sulfate > bromide > chloride > nitrate.
Expression of GPR177 (Wntless/Evi/Sprinter), a highly conserved Wnt‐transport protein, in rat tissues, zebrafish embryos, and cultured human cells
Authors: Jin Jay , Morse Megan , Frey Colleen , Petko Jessica , Levenson Robert
Published: July 2010

GPR177 is an evolutionarily conserved transmembrane protein necessary for Wnt protein secretion. Little is currently known, however, regarding expression of GPR177, especially in vertebrate species. We have developed an antiserum against GPR177, and used it to examine expression of GPR177 in human tissue culture cells, adult mouse, and rat tissues, as well as developing zebrafish embryos. In rodents, GPR177 is expressed in virtually all tissue types and brain regions examined. In zebrafish, GPR177 polypeptides are expressed throughout embryogenesis, and are detectable as early as 1 hr post‐fertilization. In situ hybridization analysis reveals that gpr177 mRNA expression is prominent in embryonic zebrafish brain and ear. Structural studies suggest that GPR177 is modified by N‐linked sugars, and that the protein contains an even number of transmembrane segments. The relatively ubiquitous expression of GPR177 suggests that this protein may serve to regulate Wnt secretion in a variety of embryonic and adult tissue types. Developmental Dynamics 239:2426–2434, 2010. © 2010 Wiley‐Liss, Inc.
Flow Injection Analysis of Aluminum Chlorohydrate in Antiperspirant Deodorants Using a Built‐in Three‐in‐one Screen‐Printed Silver Electrode
Authors: Chiu Mei‐Hsin , Kumar Annamalai Senthil , Sornambikai Sundaram , Zen Jyh‐Myng , Shih Ying
Published: July 2010

A screen‐printed silver strip with a built‐in three‐in‐one electrode (SPAgE) configuration of Ag‐working, Ag‐counter and Ag/AgxO (silver oxides) pseudoreference electrodes has been developed for sensitive and selective electrochemical flow injection analysis (FIA) of aluminum chlorohydrate (ACH) present in antiperspirants, through the free Cl− ion liberated from ACH in aqueous medium, as a redox signal at Ag‐working electrode in pH 6 phosphate buffer solution (PBS). The solution phase and instrumental parameters were systematically optimized. The calibration graph was linear in the window 1–200 ppm concentration of ACH and the lowest detection limit (S/N=3) was 295 ppb with a slope of 0.0989 μA/ppm and regression coefficient of 0.998. Calculated relative standard deviation (RSD) values for the detection of 5 and 50 ppm ACH by this method are 2.21 % and 2.16 %, respectively. Four different antiperspirant deodorants real samples with and without ACH content were successfully analyzed and the detected values obtained were found to be in good agreement with the product labeled values.
Second‐Order Data Obtained from Differential Pulse Voltammetry: Determination of Lead in River Water Using Multivariate Curve Resolution‐Alternating Least‐Squares (MCR‐ALS)
Authors: Abdollahi Hamid , Kooshki Mojtaba
Published: July 2010

Multivariate curve resolution by alternating least squares (MCR‐ALS) with the aim of achieving the electrochemical second order advantage has been applied to potential‐time second‐order data. In this work a simple way is reported as a first approach towards generation of the instrumental electrochemical second‐order data by differential pulse voltammetry (DPV). A linear dependency exists in the pulse duration profiles of the electroactive species in the mixture samples. Rank deficiency of the mixture data matrix is broken by matrix augmentation. Due to existence of potential shift in the obtained data, MCR‐ALS could not be achieved the convergence on the augmented data. So this shift was corrected with potential shift correction algorithm. Results of MCR‐ALS after shift correction show that the proposed method could be efficiently used for determination of Pb2+ in the presence of unexpected interferents in the river water sample.
Electrochemical Determination of Diclofenac Sodium in Aqueous Solution on Cu‐Doped Zeolite‐Expanded Graphite‐Epoxy Electrode
Authors: Manea Florica , Ihos Monica , Remes Adriana , Burtica Georgeta , Schoonman Joop
Published: July 2010

The electrochemical oxidation and determination of diclofenac sodium (DCF) at Cu‐doped zeolite‐modified expanded graphite‐epoxy composite (CuZEGE) electrode was evaluated for a new alternative of quantitative determination of sodium diclofenac in aqueous solutions. Cyclic voltammetry was used to characterize the electrochemical behaviour of the electrode in the presence of diclofenac sodium in a 0.1 M NaOH supporting electrolyte. This modified electrode exhibited electrocatalytic effect towards sodium diclofenac oxidation, allowing its determination in aqueous solution. The linear dependence of the current versus diclofenac concentration was obtained using cyclic voltammetry, chronoamperometry, differential‐pulsed voltammetry. The limit of detection for DCF reached by direct analysis on CuZEGE is from 2×10−5 to 3×10−7 M in relation with used technique and the potential value. Substantial enhancement of the electroanalytical parameters, e.g. the limit of detection of 5×10−8 M. for the determination of DCF at CuZEGE electrode was reached by applying a chemical preconcentration step prior to voltammetric quantification.
Effects of brace stiffness on performance of structures with supplemental Maxwell model‐based brace–damper systems
Authors: Chen Yung‐Tsang , Chai Y. H.
Published: July 2010

Shear‐type buildings with Maxwell model‐based brace–damper systems are studied in this paper with a primary emphasis on the effects of brace stiffness. A single‐story building with a viscous damper installed on top of a Chevron‐brace is first investigated. Closed‐form solutions are derived for the simple structure, relating the brace stiffness and damper coefficient to the targeted reduction in response displacement or acceleration. For a given brace stiffness, the solution is minimized to give a set of formulae that will allow the optimal damper coefficient to be determined, assuring the desired performance. The model is subsequently extended to multistory buildings with viscous dampers installed on top of Chevron‐braces. For a targeted reduction in the mean square of the interstory drift, floor acceleration or base shear force, the minimum brace stiffness and optimal damper coefficients are obtained through an iterative procedure. The response reduction, which signifies the improved performance, is achieved by a combination of brace stiffness and viscous damper coefficients, unlike conventional approaches where damper coefficients are typically optimized independent of brace stiffnesses. Characteristics of multi‐degree‐of‐freedom systems are studied using a 2‐story and a 10‐story buildings where the effects of brace stiffness on the overall performance of the building can be quantified. Copyright © 2010 John Wiley & Sons, Ltd.
Assessing severity of delirium by the delirium observation screening scale
Authors: Scheffer Alice C. , van Munster Barbara C. , Schuurmans Marieke J. , de Rooij Sophia E.
Published: July 2010

Objective

Delirium is the most common acute neuropsychiatric disorder in hospitalized elderly. Assessment of the severity of delirium is important for adjusting medication. The minimal dose of medication is preferable to prevent side effects. Only few nurse based severity measures are available. The aim of this study was to validate a scale developed to assess symptoms of delirium during regular nursing care, the Delirium Observation Screening (DOS) Scale, for monitoring severity of delirium.

Method

Delirious patients of 65 years and older were included. Delirium was diagnosed according to DSM‐IV criteria and the Confusion Assessment Method. The DOS Scale was compared to the Dutch version of the Delirium Rating Scale‐Revised‐98 (DRS‐R‐98). Global cognitive functioning was assessed by the Informant Questionnaire Cognitive Decline in the Elderly‐Short Form (IQCODE‐SF) and the KATZ‐ADL Scale was used for functional impairment.

Results

Ninety seven delirious patients were included: 41 hip fracture patients and 56 medical patients. The correlation between total DRS‐R‐98 scores and DOS Scale scores was 0.67 (p = 0.01). For the cognitive impaired group (IQCODE‐SF ≥3.9) this correlation was 0.61 (p = 0.01); for the group with no global cognitive impairment, this correlation was 0.67 (p = 0.01). Correlations between DRS‐R‐98 and DOS Scale for hypoactive, hyperactive and mixed delirium subtype were 0.40 (p = 0.32), 0.44 (p = 0.01) and 0.69 (p = 0.05), respectively.

Conclusions

The DOS Scale is able to measure severity of delirium. In routine daily clinical practice, the DOS Scale is a time‐efficient, easy to use and reliable method for measuring and monitoring severity of delirium by nurses. Copyright © 2010 John Wiley & Sons, Ltd.
Enhanced local dendritic cell activity and tumor‐specific immunoresponse in combined radiofrequency ablation and interleukin‐2 for the treatment of human head and neck cancer in a murine orthotopic model
Authors: Saito Koichiro , Araki Koji , Reddy Nishant , Guang Wei , O'Malley Bert W. , Li Daqing
Published: July 2010

Background.

Radiofrequency ablation (RFA) is a minimally invasive tumor destruction technique and can provide the antigen source initiating tumor immunity. However, induced immune response is weak and requires additional immunotherapy for optimized RFA treatment against cancer.

Methods.

A murine orthotopic model of head and neck squamous cell carcinoma (HNSCC) was established to investigate the efficacy and mechanism of an RFA + interleukin‐2 (IL‐2) combination adenoviral gene therapy among 6 groups. Tumor volume change, apoptosis, in situ macrophage recruitment, cytotoxic T lymphocyte (CTL) activity, migration of dendritic cells into the regional lymph nodes, and systemic antitumor immunity were examined.

Results.

RFA + IL‐2 therapy induced the highest levels of macrophage recruitment and dendritic cell migration resulting in enhanced CTL activity, increased tumor apoptosis, enhanced systemic antitumor immunity, and the best inhibition of tumor growth among all groups.

Conclusion.

RFA + IL‐2 combination therapy generates potent tumor immunity to suppress tumor growth in HNSCC. © 2010 Wiley Periodicals, Inc. Head Neck, 2010
Alteration of microRNA profiles in squamous cell carcinoma of the head and neck cell lines by human papillomavirus
Authors: Wald Abigail I. , Hoskins Elizabeth E. , Wells Susanne I. , Ferris Robert L. , Khan Saleem A.
Published: July 2010

Background

Human papillomavirus (HPV)‐positive cases of squamous cell carcinoma of the head and neck (SCCHN) have a much better disease outcome compared to SCCHN cases lacking HPV. Differences in microRNA (miRNA) expression may affect their clinical outcomes.

Methods

The miRNA expression was studied using microarrays and quantitative reverse transcriptase‐polymerase chain reaction (RT‐PCR) in HPV‐16‐positive and HPV‐negative SCCHN cell lines. The role of HPV‐16 E6 and E7 oncogenes in altering miRNA expression was investigated using human foreskin keratinocytes (HFKs).

Results

The miRNAs miR‐363, miR‐33, and miR‐497 were upregulated, whereas miR‐155, miR‐181a, miR‐181b, miR‐29a, miR‐218, miR‐222, miR‐221, and miR‐142‐5p were downregulated in HPV‐positive cells compared to both HPV‐negative SCCHN and normal oral keratinocytes. HPV‐16 E6 oncogene altered miRNA expression in HFKs and in an HPV‐16–positive cell line with E6 knockdown using siRNA.

Conclusion

miRNAs differentially expressed in the presence of HPV‐16 may provide biomarkers for SCCHN and identify cellular pathways targeted by this virus. © 2010 Wiley Periodicals, Inc. Head Neck, 2011
Pre-“EMT”Ing Key Processes in Liver Carcinogenesis: Growing Evidence for How Malignant Hepatocytes Invade and Conquer
Authors: Teoh Narci C.
Published: July 2010

Abstract

Chromodomain helicase/ATPase DNA binding protein 1–like gene (

CHD1L

) is a recently identified oncogene localized at 1q21, a frequently amplified region in hepatocellular carcinoma (HCC). To explore its oncogenic mechanisms, we set out to identify CHD1L-regulated genes using a chromatin immunoprecipitation–based (ChIP-based) cloning strategy in a human HCC cell line. We then further characterized 1 identified gene,

ARHGEF9

, which encodes a specific guanine nucleotide exchange factor (GEF) for the Rho small GTPase Cdc42. Overexpression of ARHGEF9 was detected in approximately half the human HCC samples analyzed and positively correlated with CHD1L overexpression. In vitro and in vivo functional studies in mice showed that CHD1L contributed to tumor cell migration, invasion, and metastasis by increasing cell motility and inducing filopodia formation and epithelial-mesenchymal transition (EMT) via ARHGEF9-mediated Cdc42 activation. Silencing ARHGEF9 expression by RNAi effectively abolished the invasive and metastatic abilities of CHD1L in mice. Furthermore, investigation of clinical HCC specimens showed that CHD1L and ARHGEF9 were markedly overexpressed in metastatic HCC tissue compared with healthy tissue. Increased expression of CHD1L was often observed at the invasive front of HCC tumors and correlated with venous infiltration, microsatellite tumor nodule formation, and poor disease-free survival. These findings suggest that CHD1L-ARHGEF9-Cdc42-EMT might be a novel pathway involved in HCC progression and metastasis.
Estimation of nonlinear models with mismeasured regressors using marginal information
Authors: Hu Yingyao , Ridder Geert
Published: July 2010

We consider the estimation of nonlinear models with mismeasured explanatory variables, when information on the marginal distribution of the true values of these variables is available. We derive a semi‐parametric MLE that is shown to be$\sqrt{n}$consistent and asymptotically normally distributed. In a simulation experiment we find that the finite sample distribution of the estimator is close to the asymptotic approximation. The semi‐parametric MLE is applied to a duration model for AFDC welfare spells with misreported welfare benefits. The marginal distribution of the correctly measured welfare benefits is obtained from an administrative source. Copyright © 2010 John Wiley & Sons, Ltd.
A CAS study on S‐loss and O‐loss dissociation mechanisms of the SO2+ ion in the C, D, and E states
Authors: Meng Qingyong , Huang Ming‐Bao
Published: July 2010

In the present work, we mainly study dissociation of the C
2B1, D2A1, and E2B2 states of the SO2+ ion using the complete active‐space self‐consistent field (CASSCF) and multiconfiguration second‐order perturbation theory (CASPT2) methods. We first performed CASPT2 potential energy curve (PEC) calculations for S‐ and O‐loss dissociation from the X, A, B, C, D, and E primarily ionization states and many quartet states. For studying S‐loss predissociation of the C, D, and E states by the quartet states to the first, second, and third S‐loss dissociation limits, the CASSCF minimum energy crossing point (MECP) calculations for the doublet/quartet state pairs were performed, and then the CASPT2 energies and CASSCF spin‐orbit couplings were calculated at the MECPs. Our calculations predict eight S‐loss predissociation processes (via MECPs and transition states) for the C, D, and E states and the energetics for these processes are reported. This study indicates that the C and D states can adiabatically dissociate to the first O‐loss dissociation limit. Our calculations (PEC and MECP) predict a predissociation process for the E state to the first O‐loss limit. Our calculations also predict that the E2B2 state could dissociate to the first S‐ and O‐loss limits via the A2B2 ← E2B2 transition. On the basis of the 13 predicted processes, we discussed the S‐ and O‐loss dissociation mechanisms of the C, D, and E states proposed in the previous experimental studies. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Supersecondary structure prediction using Chou's pseudo amino acid composition
Authors: Zou Dongsheng , He Zhongshi , He Jingyuan , Xia Yuxian
Published: July 2010

Supersecondary structures (SSSs) are the building blocks of protein 3D structures. Accurate prediction of SSSs can be one important step toward building a tertiary structure from the specified secondary structure. How to improve the accuracy of prediction of SSSs by effectively incorporating the sequence order effects is an important and challenging problem. Based on a different form of Chou's pseudo amino acid composition, a novel approach for feature representation of SSSs is proposed. Amino acid basic compositions, dipeptide components, and amino acid composition distribution are incorporated to represent the compositional features of proteins. Each supersecondary structural motif is characterized as a vector of 36 dimensions. In addition, we propose a novel prediction system by using SVM and IDQD algorithm as classifiers. Our method is trained and tested on ArchDB40 dataset containing 3088 proteins. The highest overall accuracy for the training dataset and the independent testing dataset are 77.7 and 69.4%, respectively. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011
Reply to the comment on “A stationary‐wave model of enzyme catalysis”
Authors: Canepa Carlo
Published: July 2010

This letter briefly outlines the grounds that led to an expression for reaction rate co‐efficients based on the incomplete gamma function of Euler. The proposed law explains the catalytic activity of enzymes as an effect of the coupling of active vibrational modes to the reaction coordinate, and predicts the observed negative curvature of the Arrhenius plots of the relevent reactions. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011
Comment on “A stationary‐wave model of enzyme catalysis” by Carlo Canepa
Authors: Lonsdale Richard , Harvey Jeremy N. , Manby Frederick R. , Mulholland Adrian J.
Published: July 2010

Energy barriers for enzyme‐catalyzed reactions calculated with quantum mechanics/molecular mechanics (QM/MM) and empirical valence bond (EVB) methods can be in excellent agreement with activation energies derived from experiments, supporting the applicability of transition state theory for enzymic reactions. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011
The influence of hydrating agents on the hydration of industrial magnesium oxide
Authors: Matabola Kgabo P , van der Merwe Elizabet M , Strydom Christien A , Labuschagne Frederick J W
Published: July 2010

BACKGROUND: The influence of different hydrating agents on the pH of the hydrating solutions, rate of hydration of MgO to Mg(OH)2 and product surface area was studied as a function of temperature of hydration. Hydrating agents used were aqueous solutions of ammonium chloride, magnesium acetate, magnesium nitrate, nitric acid, acetic acid, magnesium chloride, sodium acetate and hydrochloric acid and distilled water as control. These were chosen to determine either the effect of addition of a common ion, the effect of changing the solution pH or due to the presence of an acetate ion, found earlier to have a beneficial effect on the hydration of MgO.

RESULTS: There was no significant difference in the hydration behaviour of the hydrating agents up to 50 °C, where less than 10% of magnesium hydroxide was formed. The amount of hydroxide increased at temperatures above 60 °C. When compared with the hydration in water, all the hydrating agents, with the exception of sodium acetate, showed a significant increase in the degree of hydration. Sodium acetate formed the lowest amount of magnesium hydroxide, ranging between 1.2 and 12.2% magnesium hydroxide. The largest percentage (56.7%) of magnesium hydroxide was formed from hydration in magnesium acetate.

CONCLUSION: It seems that MgO hydration is a dissolution‐precipitation process controlled by the dissolution of MgO. The increased degree of hydration in magnesium acetate is possibly due to the presence of acetate and Mg2+ ions. Copyright © 2010 Society of Chemical Industry
Let's find the evidence: an analogue study of confirmation bias in criminal investigations
Authors: Rassin Eric , Eerland Anita , Kuijpers Ilse
Published: July 2010

People involved in criminal proceedings (e.g. police officers, district attorneys, judges, and jury members) may run the risk of developing confirmation bias, or tunnel vision. That is, these parties may readily become convinced that the suspect is guilty, and may then no longer be open to alternative scenarios in which the suspect is actually innocent. This may be reflected in a preference for guilt‐confirming investigation endeavours, as opposed to investigations that are aimed at confirming, or even excluding, alternative scenarios. In three studies, participants read a case file, and were subsequently instructed to select additional police investigations. Some of these additional endeavours were guilt‐confirming (i.e. incriminating), whereas others were disconfirming (i.e. exonerating). Results suggest that additional investigation search was guided by an initial assessment of the suspect's guilt (Study 1). Furthermore, participants' tendency to select incriminating investigations increased with increased crime severity, and with the strength of the evidence present in the case file. Finally, the selection of incriminating investigations was associated with conviction rates (Study 3). However, in general, participants did not favour incriminating endeavours. That is, in the three studies, the percentages of selected incriminating endeavours did hardly or not exceed 50%. Copyright © 2010 John Wiley & Sons, Ltd.
Comparison of 3.0 T proton magnetic resonance spectroscopy short and long echo‐time measures of intramyocellular lipids in obese and normal‐weight women
Authors: Bredella Miriam A. , Ghomi Reza Hosseini , Thomas Bijoy J. , Miller Karen K. , Torriani Martin
Published: July 2010

Purpose:

To compare correlations of intramyocellular lipids (IMCL) measured by short and long echo‐time proton magnetic resonance spectroscopy (1H‐MRS) with indices of body composition and insulin resistance in obese and normal‐weight women.

Materials and Methods:

We quantified IMCL of tibialis anterior (TA) and soleus (SOL) muscles in 52 premenopausal women (37 obese and 15 normal weight) using single‐voxel 1H‐MRS PRESS at 3.0 T with short (30 msec) and long (144 msec) echo times. Statistical analyses were performed to determine correlations of IMCL with body composition as determined by computed tomography (CT) and insulin resistance indices and to compare correlation coefficients from short and long echo‐time data. Signal‐to‐noise ratio (SNR), linewidth, and coefficients of variation (CV) of short and long echo‐time spectra were calculated.

Results:

Short and long echo‐time IMCL from TA and SOL significantly correlated with body mass index (BMI) and abdominal fat depots (r = 0.32 to 0.70, P = <0.05), liver density (r = −0.39 to −0.50, P < 0.05), and glucose area under the curve as a measure of insulin resistance (r = 0.47 to 0.49, P < 0.05). There was no significant difference between correlation coefficients of short and long echo‐time spectra (P > 0.5). Short echo‐time IMCL in both muscles showed significantly higher SNR (P < 0.0001) and lower CVs when compared to long echo‐time acquisitions. Linewidth measures were not significantly different between groups.

Conclusion:

IMCL quantification using short and long echo‐time 1H‐MRS at 3.0 T is useful to detect differences in muscle lipid content in obese and normal‐weight subjects. In addition, IMCL correlates with body composition and markers of insulin resistance in this population with no significant difference in correlations between short and long echo‐times. Short echo‐time IMCL quantification of TA and SOL muscles at 3.0 T was superior to long echo‐time due to better SNR and better reproducibility. J. Magn. Reson. Imaging 2010;32:388–393. © 2010 Wiley‐Liss, Inc.
The influence of the b‐value combination on apparent diffusion coefficient based differentiation between malignant and benign tissue in cervical cancer
Authors: Hoogendam Jacob P. , Klerkx Wenche M. , de Kort Gerard A.P. , Bipat Shandra , Zweemer Ronald P. , Sie‐Go Daisy M.D.S. , Verheijen René H.M. , Mali Willem P.T.M. , Veldhuis Wouter B.
Published: July 2010

Purpose:

To analyze the influence of different b‐value combinations on apparent diffusion coefficient (ADC)‐based differentiation of known malignant and benign tissue in cervical cancer patients.

Materials and Methods:

A total of 35 patients with stage IB1, IB2, IIA cervical cancer underwent a 3.0T MRI scan prior to radical hysterectomy and pelvic lymph node dissection. Conventional T1‐ and T2‐weighted sequences and a diffusion‐weighted sequence (b = 0, 150, 500, 1000 seconds/mm2) were performed. Regions‐of‐interest (ROI) were drawn on ADC maps derived from five different b‐value combinations (0, 500; 0, 150, 500; 0, 1000; 0, 150, 500, 1000; 150, 500, 1000 seconds/mm2). The influence of the b‐value combination on ADC‐based differentiation of benign and malignant tissue was analyzed using receiver‐operating‐characteristics curves.

Results:

For all b‐value combinations, ADCs were significantly lower (P < 0.001) in cervical malignancies (1.15 ± 0.21·10−3; 1.10 ± 0.21·10−3; 0.97 ± 0.18·10−3; 0.97 ± 0.23·10−3 and 0.85 ± 0.18·10−3 mm2/second respectively to the aforementioned b‐value combinations) than in benign cervix (2.08 ± 0.31·10−3; 2.00 ± 0.29·10−3; 1.62 ± 0.23·10−3; 1.54 ± 0.21·10−3 and 1.42 ± 0.22·10−3 mm2/second respectively). The diagnostic accuracy was high for all b‐value combinations and without statistical differences between the combinations.

Conclusion:

ADC‐based differentiation of benign from malignant cervical tissue is independent of the tested b‐value combinations. The results support the inclusion and possible pooling of studies using different b‐value combinations in meta‐analyses on ADC‐based tissue differentiation in cervical cancer. J. Magn. Reson. Imaging 2010;32:376–382. © 2010 Wiley‐Liss, Inc.
Two‐ and three‐dimensional multinuclear stray‐field imaging of rotating samples with magic‐angle spinning (STRAFI‐MAS): From bio to inorganic materials
Authors: Wong Alan , Sakellariou Dimitris
Published: July 2010

Purpose:

To revisit and illustrate the potential of a simple and effective multidimensional stray‐field imaging technique with magic‐angle spinning, known as STRAFI‐MAS.

Materials and Methods:

STRAFI‐MAS images are acquired with a standard NMR magnet and a traditional magic‐angle sample spinning (MAS) probe. The stray‐field gradients are achieved by placing the MAS probe, along the z‐direction, at a distance from the center of the magnet. No pulsed‐field gradients are applied. The multidimensional spatial encoding is carried out by synchronizing the radiofrequency pulses with the sample MAS rotation.

Results:

Two‐dimensional (2D) and 3D multinuclear images of various phantoms, including a tibia bone and silicon carbide, are recorded. Images of inorganic solids containing quadrupolar nuclei, 23Na and 27Al, are also explored for the first time by STRAFI‐MAS.

Conclusion:

We have demonstrated that STRAFI‐MAS is a simple and user‐friendly technique for multidimensional imaging without the need of imaging equipment. With the current advancements in NMR and MRI methodologies, STRAFI‐MAS is expected to be further developed and improved. We anticipate that STRAFI‐MAS can spark a wide spectrum of interest, from material to bio science, where can benefit from high‐resolution images. J. Magn. Reson. Imaging 2010;32:418–423. © 2010 Wiley‐Liss, Inc.
Feasibility of small bowel flow rate measurement with MRI
Authors: Gutzeit Andreas , Patak Michael A. , von Weymarn Constantin , Graf Nicole , Doert Aleksis , Willemse Edwin , Binkert Christoph A. , Froehlich Johannes M.
Published: July 2010

Objective:

To evaluate whether it is feasible to measure the segmental flux of small bowel content using MR phase‐contrast (PC) pulse sequences.

Materials and methods:

Using a phantom the accuracy of flux measurements was validated. Afterwards, 10 volunteers were included in a prospective clinical trial. To provide standardized small bowel distension, all volunteers ingested four equal portions of 400 mL of water doped with 5 mL gadoterate and 5.8 g Metamucil mite. The MR protocol covering the sagittal cross‐sections of the small bowel included several two‐dimensional (2D) PC sequences with a velocity encoding of 7 cm/second at a temporal resolution of 0.55 second. As proof of concept time‐dependent flux was measured after intravenous (i.v.) administration of a spasmolytic agent in one volunteer.

Results:

Phantom measurements resulted in an excellent correlation between pump and PC measured flow rates (R = 0.999). Time‐resolved small bowel flux was successfully measured in distended small bowel loops of all volunteers. A mean flow rate of 0.188 mL/second (standard deviation ± 0.144 mL/second) was documented. The flux plots presented a sinus wave‐like shape with regular aboral and oral flow. A spasmolytic effect both on flux and motility could be shown with residual flux despite complete arrest of small bowel motility.

Conclusion:

PC MRI allows time‐resolved in vivo measurement of small bowel flux in single well‐distended bowel loops filled with gadolinium‐doped aqueous solution. J. Magn. Reson. Imaging 2010;32:345–351. © 2010 Wiley‐Liss, Inc.
Glioma morphology and tumor‐induced vascular alterations revealed in seven rodent glioma models by in vivo magnetic resonance imaging and angiography
Authors: Doblas Sabrina , He Ting , Saunders Debbie , Pearson Jamie , Hoyle Jessica , Smith Nataliya , Lerner Megan , Towner Rheal A.
Published: July 2010

Purpose:

To evaluate the added value of non–contrast‐enhanced MR angiography (MRA) to conventional MR imaging for a detailed characterization of different rodent glioma models.

Materials and Methods:

Intracerebral tumor cell implantation and chemical induction methods were implemented to obtain rat C6, 9L/LacZ, F98, RG2, and ethyl‐nitrosourea (ENU) ‐induced glioma models, a human U87 MG tumor model as well as a mouse GL261 glioma model. MR assessments were regularly conducted on a 7 Tesla Bruker BioSpin system. The tumor border sharpness and growth characteristics of each glioma model were assessed from T2‐weighted images. Neovascularization and vascular alterations inherent to each model were characterized by assessing absolute blood volumes, vessel density, length, and diameter using Mathematica and Amira software.

Results:

The 9L/LacZ and ENU gliomas both presented flaws that hinder their use as reliable brain tumor models. C6 gliomas were slightly invasive and induced moderate vascular alterations, whereas GL261 tumors dramatically altered the brain vessels in the glioma region. F98, RG2, and U87 are infiltrative models that produced dramatic vascular alterations.

Conclusion:

MRI and MRA provided crucial in vivo information to identify a distinctive “fingerprint” for each of our seven rodent glioma models. J. Magn. Reson. Imaging 2010;32:267–275. © 2010 Wiley‐Liss, Inc.
Interindividual, repositioning, and time‐of‐day effects on single voxel proton MR spectroscopy of the anterior cingulate cortex
Authors: Soreni Noam , Noseworthy Michael D. , Konyer Norman B. , Pullenayegum Eleanor , Schachar Russell
Published: July 2010

Purpose:

To measure interindividual, repositioning, and time‐of‐day effects of single voxel PRESS (Point RESolved Spectroscopy) proton magnetic resonance spectroscopy (1H‐MRS) acquisition of the anterior cingulate cortex (AC) in healthy human subjects.

Materials and Methods:

AC 1H‐MRS measurements were performed in 15 healthy adult volunteers using a short echo PRESS sequence (GE Healthcare 3 Tesla, TE/TR = 30/2500 ms, 192 acquisitions, 6 cm3 voxels). For each individual, a total of eight spectra were obtained during two identical scanning sessions separated by 3.5 h. In each, two consecutive AC spectra were acquired. After the first two scans, the subject left the scanner, then immediately returned for repositioning and acquisition of two more consecutive spectra. The subject then left the imaging centre to return 3.5 h later for a repeated procedure. Spectroscopic postprocessing was done using LCmodel. Interindividual, repositioning and time‐of‐day effects were measured using restricted maximum likelihood (REML) models of variance components analysis, where response variables were levels of creatine/phosphocreatine (Cr), N‐acetyl‐aspartate (NAA), myo‐inositol (mI), choline (Cho), and the glutamate‐glutamine complex (Glx).

Results:

Interindividual effects were markedly higher than time‐of‐day and repositioning effects for all metabolites.

Conclusion:

Our findings show that 1H‐MRS measurements of the AC are sensitive to interindividual differences, while time of day and repositioning are markedly less important. J. Magn. Reson. Imaging 2010;32:276–282. © 2010 Wiley‐Liss, Inc.
Ultra‐short echo time (UTE) MR imaging of the lung: Comparison between normal and emphysematous lungs in mutant mice
Authors: Takahashi Masaya , Togao Osamu , Obara Makoto , van Cauteren Marc , Ohno Yoshiharu , Doi Shigehiro , Kuro‐O Makoto , Malloy Craig , Hsia Connie C. , Dimitrov Ivan
Published: July 2010

Purpose:

To investigate the utility of ultra‐short echo time (UTE) sequence as pulmonary MRI to detect non‐uniform disruption of lung architecture that is typical of emphysema.

Materials and Methods:

MRI of the lungs was conducted with a three‐dimensional UTE sequence in transgenic mice with severe emphysema and their wild‐type littermates in a 3 Tesla clinical MR system. Measurements of the signal intensity (SI) and transverse relaxation time (T2*) of the lung parenchyma were performed with various echo times (TEs) ranging from 100 μs to 2 ms.

Results:

Much higher SI of the lung parenchyma was observed at an UTE of 100 μs compared with longer TEs. The emphysematous lungs had reduced SIs and T2* than the controls, in particular at end‐expiratory phase. The results suggested that both SI and T2* in lung parenchyma measured with the method represent fractional volume of lung tissue.

Conclusion:

The UTE imaging provided MR signal from the lung parenchyma. Moreover, the UTE sequence was sensitive to emphysematous changes and may provide a direct assessment of lung parenchyma. UTE imaging has the potential to assist detection of localized pathological destruction of lung tissue architecture in emphysema. J. Magn. Reson. Imaging 2010;32:326–333. © 2010 Wiley‐Liss, Inc.
Best‐practice recommendations for estimating interaction effects using meta‐analysis
Authors: Aguinis Herman , Gottfredson Ryan K. , Wright Thomas A.
Published: July 2010

One of the key advantages of meta‐analysis (i.e., a quantitative literature review) over a narrative literature review is that it allows for formal tests of interaction effects—namely, whether the relationship between two variables is contingent upon the value of another (moderator) variable. Interaction effects play a central role in organizational science research because they highlight boundary conditions of a theory: Conditions under which relationships change in strength and/or direction. This article describes procedures for estimating interaction effects using meta‐analysis, distills the technical literature for a general readership of organizational science researchers, and includes specific best‐practice recommendations regarding actions researchers can take before and after data collection to improve the accuracy of substantive conclusions regarding interaction effects investigated meta‐analytically. Copyright © 2010 John Wiley & Sons, Ltd.
Changing rainfall, seasonality and erosivity in the hyper‐arid zone of Sudan
Authors: Elagib N. A.
Published: July 2010

A primary cause of soil erosion is the impact of rain. Therefore, understanding the altering rainfall characteristics and their effect on soil erosion is an issue of main concern. This is of utmost importance to contribute to developing suitable adaptation and mitigation strategies for soil and water resources conservation and crop management practices.

The rainfall seasonality index (SI), precipitation concentration index (PCI) and modified Fournier index (MFI) for rainfall erosivity have been calculated and analysed in this study for the hyper‐arid region of Sudan. The data used consist of monthly rainfall measurements spanning over 60 years for three index meteorological stations, two on the Nile corridor and one on the Red Sea coast. The region is characterized by high year‐to‐year variability in rainfall leading to extreme seasonality/irregular distribution of rainfall over the year. Although prevalent diminishing rainfall amounts have been witnessed, there are marked tendencies for some months to become wetter, indicating changing intra‐annual rainfall variability and thus monthly rainfall erosivity. No statistically significant trends were observed in rainfall seasonality and concentration during the common data period of 1945–2007. Cases of high and very high erosion powers were detected. A significant decreasing trend in erosivity is shown for one inland station. A brief discussion on the implications of these results for risk of soil erosion, freshwater quality and agriculture is also given. Copyright © 2010 John Wiley & Sons, Ltd.
Au/CdS Hybrid Nanoparticles in Block Copolymer Micellar Shells
Authors: Koh Haeng‐Deog , Changez Mohammad , Lee Jae‐Suk
Published: July 2010

A polystyrene‐block‐poly(2‐vinylpyridine) (PS‐b‐P2VP) micellar structure with a P2VP core containing 5 nm CdS nanoparticles (NPs) and a PS shell formed in toluene that is a good solvent for PS block undergoes the core‐shell inversion by excess addition of methanol that is a good solvent for P2VP block. It leads to the formation of micellar shell‐embedded CdS NPs in the methanol major phase. The spontaneous crystalline growth of Au NPs on the CdS surfaces positioned at micellar shells without a further reduction process is newly demonstrated. The nanostructure of Au/CdS/PS‐b‐P2VP hybrid NPs is confirmed by transmission electron microscopy, energy‐dispersive X‐ray, and UV‐Vis absorption.

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Influence of spray forming process parameters on the microstructure and porosity of Mg2Si rich aluminum alloys
Authors: Ellendt N. , Stelling O. , Uhlenwinkel V. , von Hehl A. , Krug P.
Published: July 2010

Due to high cooling rates spray forming is an appropriate process to produce aluminum alloys with a high content of Mg2Si. Compared to common casting processes, a fine microstructure can be achieved yielding in improved mechanical properties. In this work, billets were spray formed from the two alloys AlMg15Si8Cu2 (22 mass‐% Mg2Si) and AlMg20.5Si11Cu2 (30 mass‐% Mg2Si) under different spraying conditions. The analysis of the microstructure showed that the size of Mg2Si dispersoids is very sensitive to process parameters. Besides the well known thermal effects of melt superheat (carried out from –40 K to +170 K) and GMR (varied from 2.0 to 6.3) a strong influence of the scanning frequency of the atomizer nozzle (7 Hz and 15 Hz) could be observed. Similar effects could be found for the occurrence of porosity. A new parameter, the enthalpy flow to gas flow ratio (EGR), was defined from these two parameters of which correlations of Mg2Si dispersoid size and amount of porosity were found.

Auf Grund der hohen auftretenden Abkühlraten ist das Sprühkompaktieren ein geeigneter Prozess zur Herstellung von Aluminium‐Legierungen mit hohen Gehalten an Mg2Si. Im Vergleich zu konventionellen Gießverfahren ergibt sich eine deutlich feinere Mikrostruktur mit entsprechend verbesserten mechanischen Eigenschaften. In den durchgeführten Untersuchungen wurden Bolzen aus den Legierungen AlMg15Si8Cu2 (22 Massen‐% Mg2Si) und AlMg20,5Si11Cu2 (30 Massen‐% Mg2Si) mit verschiedenen Prozessparametern sprühkompaktiert. Eine Analyse der Mikrostruktur zeigte, dass die Größe der Mg2Si‐Dispersoide stark von den Prozessparametern abhängt. Neben bekannten thermischen Effekten der Schmelzeüberhitzung (variiert zwischen –40 K und 170 K) und des GMR (variiert von 2,0 bis 6,3) konnte ein starker Einfluss der Scanfrequenz (7 und 15 Hz) festgestellt werden. Ähnliche Effekte traten hinsichtlich der Porosität im gesprühten Material auf. Ein neuer Parameter, das Enthalpie‐ zu Gasmassenstrom‐Verhältnis (EGR) wurde auf der Basis der Parameter Schmelzeüberhitzung und GMR gebildet. Es zeigten sich Abhängigkeiten der Dispersoidgröße und der Porosität von diesem neuen Parameter.