bluuebunny/crossref_metadata_2025 huggingface dataset:
Tuning the properties of the bacterial membrane with aminoacylated phosphatidylglycerol
Authors: Roy Hervé
Published: September 2009

The bacterial envelope is a semi‐permeable barrier that protects the cell from the hostilities of the environment. To survive the ever‐changing conditions of their surroundings, bacteria need to rapidly adjust the biochemical properties of their cellular envelope. Amino acid (aa) addition to phosphatidylglycerol (PG) of the membrane is one of the mechanisms used by bacteria to lower the net negative charge of their cellular envelope, thereby decreasing its affinity for several antibacterial agents such as the cationic antimicrobial peptides (CAMPs) produced by the innate immune response during host infection. This process requires the activity of an integral membrane protein, called aa‐PG synthase (aaPGS), to transfer the aa of aminoacyl‐tRNA (aa‐tRNA) onto the PG of the membrane. aaPGSs constitute a new family of virulence factors that are found in a wide range of microorganisms. aa‐PGs not only provide resistance to CAMPs but also to other classes of antibacterial agents and to environmental stresses such as those encountered during extreme osmotic or acidic conditions. This review will describe the known biochemical properties of aa‐PGSs, their specificity for aa‐tRNAs and phospholipids, and the growing repertoire of aa used as substrates by these enzymes. Their prevalence in bacteria and the phenotypes and modulations of membrane properties associated with these molecules will be addressed, as well as their regulation as a component of the envelope stress response system in certain bacteria. © 2009 IUBMB IUBMB Life, 61(10): 940–953, 2009
Androgen receptor and caveolin‐1 in prostate cancer
Authors: Bennett Nigel , Hooper John D. , Lee C. Soon , Gobe Glenda C.
Published: September 2009

The androgen receptor (AR) is involved in the development and maintenance of the normal prostate and the development and progression of prostate cancer (PCa). Caveolin‐1 (cav‐1) is an AR co‐regulator. The expression of this integral membrane protein is upregulated in PCa and correlates positively with its development. This review focuses on the likely interactive roles of AR and cav‐1, with particular reference to progression to androgen‐insensitivity in PCa. The classical role of AR is modulation of gene transcription by binding specific DNA sequences called androgen response elements in the promoter regions of target genes. To carry out this role, AR interacts with many co‐regulator proteins which either enhance or repress its activation. Altered expression or misregulated activation of a co‐regulator protein may significantly alter AR activity and the basal transcription rate of androgen responsive genes. Cav‐1 has roles in cell signalling and trafficking, roles that are important in PCa survival, metastasis, and the development of multidrug resistant phenotypes. Although cav‐1 appears to increase AR genomic activity and increase tumor cell survival, there is also mounting evidence that cav‐1 can manipulate rapid, non‐genomic AR signalling at the plasma membrane. By increasing our understanding of cav‐1 as an AR co‐regulator, we may be able to reinstate appropriate transcriptional responses to androgen signalling and minimise misregulated AR activity, thus permitting more effective targeted therapies for PCa. © 2009 IUBMB IUBMB Life, 61(10): 961–970, 2009
Emerging roles of glucocorticoid receptor phosphorylation in modulating glucocorticoid hormone action in health and disease
Authors: Galliher‐Beckley Amy J. , Cidlowski John A.
Published: September 2009

Glucocorticoids (GCs) are hormones naturally released when the body perceives stress and function to return homeostatic balance within various tissues. Synthetic GCs are widely prescribed therapeutics for the treatment of numerous inflammatory disorders and cancers. The effects of GCs are mediated by their binding and activation of the GC receptor (GR), a transcription factor that is subject to hormone‐dependent and ‐independent phosphorylation on several serine and threonine residues. The GR is phosphorylated by kinases such as MAPKs, CDKs, and GSK‐3β, and these modifications modulate the transcriptional activity of the GR within cells. Here, we discuss the phosphorylation status of the GR as a mechanism to dictate how cells will ultimately respond to GCs. In doing so, we will review current knowledge about each phosphorylated residue within the GR and their contributions to modulating GC signaling in normal homeostatic physiology and during the progression of disease. © 2009 IUBMB IUBMB Life, 61(10): 979–986, 2009
Models of stochastic choice and decision theories: why both are important for analyzing decisions
Authors: Blavatskyy Pavlo R. , Pogrebna Ganna
Published: September 2009

We select a menu of seven popular decision theories and embed each theory in five models of stochastic choice, including tremble, Fechner and random utility model. We find that the estimated parameters of decision theories differ significantly when theories are combined with different models. Depending on the selected model of stochastic choice we obtain different rankings of decision theories with regard to their goodness of fit to the data. The fit of all analyzed decision theories improves significantly when they are embedded in a Fechner model of heteroscedastic truncated errors or a random utility model. Copyright © 2009 John Wiley & Sons, Ltd.
Estimating time variation in measurement error from data revisions: an application to backcasting and forecasting in dynamic models
Authors: Kapetanios George , Yates Tony
Published: September 2009

Over time, economic statistics are refined. This implies that data measuring recent economic events are typically less reliable than older data. Such time variation in measurement error affects optimal forecasts. Measurement error, and its time variation, are of course unobserved. Our contribution is to show how estimates of these can be recovered from the variance of revisions to data using a behavioural model of the statistics agency. We illustrate the gains in forecasting performance from exploiting these estimates using a real‐time dataset on UK aggregate expenditure data. Copyright © 2009 John Wiley & Sons, Ltd.
International evidence on the efficacy of new‐Keynesian models of inflation persistence
Authors: Korenok Oleg , Radchenko Stanislav , Swanson Norman R.
Published: September 2009

We take an agnostic view of the Phillips curve debate, and carry out an empirical investigation of the relative and absolute efficacy of Calvo sticky price (SP), sticky information (SI), and sticky price with indexation models (SPI), with emphasis on their ability to mimic inflationary dynamics. We look at evidence for a group of 13 OECD countries, and consider three alternative measures of inflationary pressure, including the output gap, labor share, and unemployment. We find that the SPI model is preferable to the Calvo SP and the SI models because it captures the type of strong inflationary persistence that has in the past characterized the economies in our sample. However, two caveats to this conclusion are that improvement in performance is driven mostly by lagged inflation and that the SPI model overemphasizes inflationary persistence. There appears to be room for improvement in all models in order to induce them to better ‘track’ inflation persistence. Copyright © 2009 John Wiley & Sons, Ltd.
Toward a practical protocol for human optic nerve DTI with EPI geometric distortion correction
Authors: Techavipoo Udomchai , Okai Annette F. , Lackey John , Shi Jianrong , Dresner Michael A. , Leist Thomas P. , Lai Song
Published: September 2009

Purpose

To develop a practical protocol for diffusion tensor imaging (DTI) of the human optic nerve with echo planar imaging (EPI) geometric distortion correction.

Materials and Methods

A conventional DTI protocol was modified to acquire images with fat and cerebrospinal fluid (CSF) suppression and field inhomogeneity maps of contiguous coronal slices covering the whole brain. The technique was applied to healthy volunteers and multiple sclerosis patients with and without a history of unilateral optic neuritis. DTI measures and optic nerve tractography before and after geometric distortion correction were compared. Diffusion measures from left and right or from affected and unaffected eyes in different subject cohorts were reported.

Results

The image geometry after correction closely resembled reference anatomical images. Optic nerve tractography became feasible after distortion correction. The diffusion measures from the healthy volunteers were in good agreement with the literature. Statistically significant differences were found in the fractional anisotropy and orthogonal eigenvalues between affected and unaffected eyes in optic neuritis patients with poor recovery. The diffusion measures before and after geometric distortion correction were not significantly different. For cohorts without optic neuritis, the difference between diffusion measures from left and right eyes was not statistically significant.

Conclusion

The proposed technique could provide a practical DTI protocol to study the human optic nerve. J. Magn. Reson. Imaging 2009;30:699–707. © 2009 Wiley‐Liss, Inc.
High resolution fast T1 mapping technique for dGEMRIC
Authors: Sur Samir , Mamisch Tallal Charles , Hughes Timothy , Kim Young‐Jo
Published: September 2009

Purpose

To determine the feasibility of using a high resolution isotropic three‐dimensional (3D) fast T1 mapping sequence for delayed gadolinium‐enhanced MRI of cartilage (dGEMRIC) to assess osteoarthritis in the hip.

Materials and Methods

T1 maps of the hip were acquired using both low and high resolution techniques following the administration of 0.2 mmol/kg Gd‐DTPA2‐ in 35 patients. Both T1 maps were generated from two separate spoiled GRE images. The high resolution T1 map was reconstructed in the anatomically equivalent plane as the low resolution map. T1 values from the equivalent anatomic regions containing femoral and acetabular cartilages were measured on the low and high resolution maps and compared using regression analysis.

Results

In vivo T1 measurements showed a statistically significant correlation between the low and high resolution acquisitions at 1.5 Tesla (R2 = 0.958, P < 0.001). These results demonstrate the feasibility of using a fast two‐angle T1 mapping (F2T1) sequence with isotropic spatial resolution (0.8 × 0.8 × 0.8 mm) for quantitative assessment of biochemical status in articular cartilage of the hip.

Conclusion

The high resolution 3D F2T1 sequence provides accurate T1 measurements in femoral and acetabular cartilages of the hip, which enables the biochemical assessment of articular cartilage in any plane through the joint. It is a powerful tool for researchers and clinicians to acquire high resolution data in a reasonable scan time (< 30 min). J. Magn. Reson. Imaging 2009;30:896–900. © 2009 Wiley‐Liss, Inc.
Left ventricular infarct size, peri‐infarct zone, and papillary scar measurements: A comparison of high‐resolution 3D and conventional 2D late gadolinium enhancement cardiac MR
Authors: Peters Dana C. , Appelbaum Evan A. , Nezafat Reza , Dokhan Basem , Han Yuchi , Kissinger Kraig V. , Goddu Beth , Manning Warren J.
Published: September 2009

Purpose

To compare higher spatial resolution 3D late gadolinium enhancement (LGE) cardiovascular magnetic resonance (Cardiac MR) with 2D LGE in patients with prior myocardial infarction.

Materials and Methods

Fourteen patients were studied using high spatial resolution 3D LGE (1.3 × 1.3 × 5.0 mm3) and conventional 2D LGE (2 × 2 × 8 mm3) scans. The signal‐to‐noise ratio (SNR) and contrast‐to‐noise ratio (CNR) were measured. Total infarct volume, peri‐infarct volume measured in a limited slab, and papillary muscle scar volume were compared using Bland–Altman analysis. Image quality was graded.

Results

3D LGE had higher scar SNR (P < 0.001), higher myocardial SNR (P = 0.001), higher papillary scar‐blood CNR (P = 0.01), and greater sharpness (P = 0.01). The scar volumes agreed (14.5 ± 8.2 for 2D, vs. 13.2 ± 8.8 for 3D), with bias ± 2 standard deviations (SDs) of 0.5 ± 6.8 mL, P = 0.59 R = 0.91. The peri‐infarct volumes correlated but less strongly than scar (P = 0.40, R = 0.77). For patients with more heterogeneous scar, larger peri‐infarct volumes were measured by 3D (1.9 ± 1.1 mL for 2D vs. 2.4 ± 1.6 mL for 3D, P = 0.15, in the matched region). Papillary scar, present in 6/14 (42%) patients, was more confidently identified on 3D LGE.

Conclusion

Higher spatial resolution 3D LGE provides sharper images and higher SNR, but less myocardial nulling. Scar volumes agree well, with peri‐infarct volumes correlating less well. 3D LGE may be superior in visualization of papillary muscle scar. J. Magn. Reson. Imaging 2009;30:794–800. © 2009 Wiley‐Liss, Inc.
Comprehensive adenosine stress perfusion MRI defines the etiology of chest pain in the emergency room: Comparison with nuclear stress test
Authors: Vogel‐Claussen Jens , Skrok Jan , Dombroski David , Shea Steven M. , Shapiro Edward P. , Bohlman Mark , Lorenz Christine H. , Lima Joao A.C. , Bluemke David A.
Published: September 2009

Purpose

To compare standard of care nuclear SPECT imaging with cardiac magnetic resonance imaging (MRI) for emergency room (ER) patients with chest pain and intermediate probability for coronary artery disease.

Materials and Methods

Thirty‐one patients with chest pain, negative electrocardiogram (ECG), and negative cardiac enzymes who underwent cardiac single photon emission tomography (SPECT) within 24 h of ER admission were enrolled. Patients underwent a comprehensive cardiac MRI exam including gated cine imaging, adenosine stress and rest perfusion imaging and delayed enhancement imaging. Patients were followed for 14 ± 4.7 months.

Results

Of 27 patients, 8 (30%) showed subendocardial hypoperfusion on MRI that was not detected on SPECT. These patients had a higher rate of diabetes (P = 0.01) and hypertension (P = 0.01) and a lower global myocardial perfusion reserve (P = 0.01) compared with patients with a normal cardiac MRI (n = 10). Patients with subendocardial hypoperfusion had more risk factors for cardiovascular disease (mean 4.4) compared with patients with a normal MRI (mean 2.5; P = 0.005). During the follow‐up period, patients with subendocardial hypoperfusion on stress MRI were more likely to return to the ER with chest pain compared with patients who had a normal cardiac MRI (P = 0.02). Four patients did not finish the MR exam due to claustrophobia.

Conclusion

In patients with chest pain, diabetes and hypertension, cardiac stress perfusion MRI identified diffuse subendocardial hypoperfusion defects in the ER setting not seen on cardiac SPECT, which is suspected to reflect microvascular disease. J. Magn. Reson. Imaging 2009;30:753–762. © 2009 Wiley‐Liss, Inc.
Gadolinium pharmacokinetics of chronic myocardial infarcts: Implications for late gadolinium‐enhanced infarct imaging
Authors: Goldfarb James W. , Arnold Sheeba , Roth Marguerite
Published: September 2009

Purpose

To monitor gadolinium pharmacokinetics in the hearts of patients with chronic myocardial infarcts and to determine the variability of contrast agent concentrations and accuracy of infarct detection over an hour time period.

Materials and Methods

Twenty‐five patients with chronic myocardial infarcts were examined. T1 measurements were performed every 2 minutes using an inversion recovery CINE balanced steady‐state free precession technique. Paired differences in T1 values over time for the discrimination between the left ventricular (LV) bloodpool, viable, and infarct myocardium were statistically evaluated. The average change per 1, 5, and 10 minutes of the inversion time parameter for optimal nulling of viable myocardium was calculated. Receiver operator characteristic (ROC) curve analysis was performed to compare the performance of late gadolinium‐enhanced infarct imaging at increasing delays after contrast agent administration.

Results

Significantly different T1 values were reached after 10 minutes between the LV bloodpool, infarcted, and viable myocardium. The T1 difference between myocardial infarcts and the LV bloodpool increased over time, while the difference between viable myocardium and the LV bloodpool decreased. ROC curve analysis showed a decrease in performance of a fixed T1 value to discriminate between the LV bloodpool and viable myocardium over time, while there was a marked increase in the discrimination between the LV bloodpool and infarcted myocardium.

Conclusion

The ability to discriminate between infarcted myocardium and the LV bloodpool improves with an increasing delay after contrast agent administration while discrimination between viable myocardium and the LV bloodpool decreases. J. Magn. Reson. Imaging 2009;30:763–770. © 2009 Wiley‐Liss, Inc.
Multicontrast late gadolinium enhancement imaging enables viability and wall motion assessment in a single acquisition with reduced scan times
Authors: Connelly Kim A. , Detsky Jay S. , Graham John J. , Paul Gideon , Vijayaragavan Ram , Dick Alexander J. , Wright Graham A.
Published: September 2009

Purpose

To determine the accuracy of multicontrast late enhancement imaging (MCLE) in the assessment of myocardial viability and wall motion compared to the conventional wall motion and viability cardiac magnetic resonance imaging (MRI) pulse sequences.

Materials and Methods

Forty‐one patients with suspected myocardial infarction were studied. Patients underwent assessment of cardiac function with cine steady‐state free‐precession (SSFP), followed by late gadolinium enhancement (LGE) imaging using inversion recovery gradient echo scanning (IR‐GRE) sequence and MCLE. MCLE was compared to cine SSFP in the assessment of wall motion, ejection fraction (EF), left ventricular (LV) mass, LV end‐diastolic volume (EDV), and to IR‐GRE for measuring infarct size.

Results

MCLE, IR‐GRE, and SSFP imaging demonstrated excellent agreement in the assessment of EF, LV infarct size, and LV mass (r > 0.95, P < 0.001 for all measures), as well as in the assessment of wall motion (κ statistic 0.75).

Conclusion

MCLE provided coregistered images for the assessment of viability and wall motion without loss of accuracy in the assessment of quantitative cardiac parameters. MCLE provides accurate quantitative cardiac assessment with reduced scan times compared to the conventional sequences and thus may be used as an alternative to conventional cine SSFP and IR‐GRE imaging. J. Magn. Reson. Imaging 2009;30:771–777. © 2009 Wiley‐Liss, Inc.
Cyclic motion encoding for enhanced MR visualization of slip interfaces
Authors: Mariappan Yogesh K. , Glaser Kevin J. , Manduca Armando , Ehman Richard L.
Published: September 2009

Purpose

To develop and test a magnetic resonance imaging‐based method for assessing the mechanical shear connectivity across tissue interfaces with phantom experiments and in vivo feasibility studies.

Materials and Methods

External vibrations were applied to phantoms and tissue and the differential motion on either side of interfaces within the media was mapped onto the phase of the MR images using cyclic motion encoding gradients. The phase variations within the voxels of functional slip interfaces reduced the net magnitude signal in those regions, thus enhancing their visualization. A simple two‐compartment model was developed to relate this signal loss to the intravoxel phase variations. In vivo studies of the abdomen and forearm were performed to visualize slip interfaces in healthy volunteers.

Results

The phantom experiments demonstrated that the proposed technique can assess the functionality of shear slip interfaces and they provided experimental validation for the theoretical model developed. Studies of the abdomen showed that the slip interface between the small bowel and the peritoneal wall can be visualized. In the forearm, this technique was able to depict the slip interfaces between the functional compartments of the extrinsic forearm muscles.

Conclusion

Functional shear slip interfaces can be visualized sensitively using cyclic motion encoding of externally applied tissue vibrations. J. Magn. Reson. Imaging 2009;30:855–863. © 2009 Wiley‐Liss, Inc.
Influence of the compliance of the neck arteries and veins on the measurement of intracranial volume change by phase‐contrast MRI
Authors: Tain Rong‐Wen , Ertl‐Wagner Birgit , Alperin Noam
Published: September 2009

Purpose

To assess the influence of arterial and venous vascular compliances in the neck region on the measurement of the change in intracranial volume during the cardiac cycle.

Materials and Methods

Arterial and venous blood flows were imaged by MRI phase contrast at two different locations, one close to the skull base (upper) and one 2–3 cm lower, around C3 level (lower). Maximal intracranial volume change (ICVC) measurements were derived from the momentary difference between the arterial inflow and venous outflow rates at the upper and lower locations separately to assess the influence of the compliances of the vessel segments bounded by the two different imaging locations. Imaging location for the craniospinal cerebrospinal fluid flow was a constant variable in this experiment.

Results

The systolic ICVC obtained using the lower location was consistently larger than when using the upper location. Comparison between arterial and venous flow dynamics revealed a much larger changes in flow dynamic and lumen areas in the veins compared with the arteries, which explain the large venous influence on the intracranial volume change measurement.

Conclusion

Arterial inflow and venous outflow should be sampled at a level close to the skull base (C1–C2) to minimize the influence of the compliance of arteries and the collapsibility of veins for a reliable measurement of ICVC. J. Magn. Reson. Imaging 2009;30:878–883. © 2009 Wiley‐Liss, Inc.
Detecting lesions in multiple sclerosis at 4.7 tesla using phase susceptibility‐weighting and T2‐weighting
Authors: Eissa Amir , Lebel R. Marc , Korzan Jeff R. , Zavodni Anna E. , Warren Kenneth G. , Catz Ingrid , Emery Derek J. , Wilman Alan H.
Published: September 2009

Purpose

To demonstrate 4.7 Tesla (T) imaging methods for visualizing lesions in multiple sclerosis in the human brain using phase susceptibility‐weighting and T2 weighting.

Materials and Methods

Seven patients with relapsing‐remitting multiple sclerosis were imaged at 4.7T using three‐dimensional (3D) susceptibility‐weighted imaging (SWI) with 0.90 mm3 voxel volumes, and with 2D T2‐weighted fast spin echo (T2WFSE) with 0.34 mm3 voxels and 1.84 mm3 voxels. The visibility of MS lesions at 4.7T with phase SWI and T2WFSE was assessed by independent lesion counts made by an experienced neuroradiologist, and by quantitative measures.

Results

High resolution T2WFSE at 4.7T provided excellent depiction of hyperintense lesions. When combined with phase SWI, 124 total lesions were identified of which 18% were only visible on phase SWI and not on T2WFSE. The phase lesions had a mean phase shift relative to local background of −11.15 ± 5.97 parts per billion.

Conclusion

Imaging at 4.7T can provide both high quality, high resolution T2WFSE and SWI for visualization of lesions in multiple sclerosis. Phase susceptibility‐weighting can identify additional lesions that are not visible with high resolution T2WFSE. J. Magn. Reson. Imaging 2009;30:737–742. © 2009 Wiley‐Liss, Inc.
Interaction between rhodanine and silver species on a nanocolloidal surface and in the solid state
Authors: Marzec Katarzyna M. , Gawel Bartlomiej , Lasocha Wieslaw , Proniewicz Leonard M. , Malek Kamilla
Published: September 2009

This paper discusses and compares molecular interactions of rhodanine (Rd), the heterocyclic compound containing N, S, and O atoms, with two forms of silver species, i.e. Ag(I) ions and silver nanocolloidal particles. Vibrational spectroscopic and powder crystallography studies on coordination of Ag(I) ions in the solid state, supported by density functional theory, clearly indicate complexation through the nitrogen (the deprotonated imino group) and exocyclic sulfur atoms. Molecules of the complex are arranged in a one‐dimensional infinite polymeric chain structure that intertwines to give a helix motif. On the other hand, adsorption geometry of Rd on the silver surface was determined by using surface‐enhancement Raman scattering (SERS) spectroscopy. Observed differences between the SERS and the normal Raman spectra of Rd suggest that Rd adsorbs on the silver species after the rearrangement of the keto‐thione form into the enol‐thiol tautomer in acidic and neutral solutions. This leads to adsorption on this silver species through the thiolate ion. On the other hand, the alkaline pH forces first N‐deprotonation of Rd, and, in consequence, the obtained anion of the keto‐thione form interacts with the silver surface as a result of the presence of lone pairs of nitrogen and sulfur atoms, similar to the case discussed for the solid state. Copyright © 2009 John Wiley & Sons, Ltd.
Screening quality and browning susceptibility of five artichoke cultivars for fresh‐cut processing
Authors: Cabezas‐Serrano Ana B , Amodio Maria L , Cornacchia Rosaria , Rinaldi Raffaella , Colelli Giancarlo
Published: September 2009

BACKGROUND: Artichoke is a rich source of bioactive compounds, mainly phenols, in the Mediterranean diet, but its consumption is limited by the complexity of time‐consuming trimming operations. Fresh‐cut processing would therefore add convenience to its consumption, even though the severity of post‐cutting browning of artichoke pieces is still a major problem. Since susceptibility to browning may vary widely among genotypes, the choice of the cultivar is a very critical step in the fresh‐cut process. In this study, five different Italian cultivars (C3, Catanese, Tema, Violetto Foggiano and Violetto Sardo) were screened for their initial quality and composition, and their post‐cutting performance during storage at 5 °C and 20 °C.

RESULTS: C3 showed the highest phenol content (3.4 g GA kg−1) and antioxidant activity (24.5 mmol L−1 kg−1), but the worst quality in terms of appearance and colour changes, also due to its high PPO activity (62.2 U g−1). Catanese showed the highest vitamin C content (117.7 mg kg−1), the lowest phenol content (1.8 g GA kg−1), and the best post‐cutting quality. Tema, Violetto Foggiano and Violetto Sardo showed an intermediate phenol content, the latter showing the lowest appearance score after C3.

CONCLUSION: These results confirmed the role of phenols in browning processes of fresh‐cut artichokes, giving the first available information on artichoke cultivar suitability to be processed as a fresh‐cut product. Copyright © 2009 Society of Chemical Industry
Learning styles in two otolaryngology residency programs
Authors: Laeeq Kulsoom , Weatherly Robert A. , Carrott Alice , Pandian Vinciya , Cummings Charles W. , Bhatti Nasir I.
Published: September 2009

Objectives/Hypothesis:

Kolb portrays four learning styles depending on how an individual grasps or transforms experience: accommodating, assimilating, diverging, and converging. Past studies in surgery, medicine, and anesthesia identified the predominant learning style in each of these specialties. The prevalence of different learning styles and existence of a predominant style, if any, has not been reported for otolaryngology residency programs. The purpose of our study was to determine if otolaryngology residents have a preferred learning style that is different from the predominant learning styles reported for other specialties.

Study Design:

We conducted a survey of the otolaryngology‐head and neck surgery residents at two residency programs.

Methods:

Kolb's Learning Style Index (LSI) version 3.1 was administered to 46 residents from Johns Hopkins University and Kansas University Otolaryngology–Head and Neck Surgery programs. LSI is a widely used 12‐item questionnaire, with each item followed by four options. The subjects graded the options depending on how the options applied to them.

Results:

Forty‐three otolaryngology residents completed the survey, with a response rate of 93.47%. The predominant learning style was converging (55.81%) followed by accommodating (18.61%), accounting for the learning styles of 74.42% of the total population. There were only 13.95% assimilating and 6.98% diverging learning styles. Two residents (4.65%) had their preference balanced across four learning styles.

Conclusions:

The predominant learning styles in otolaryngology were converging and accommodating, accounting for three fourths of the population. It would be desirable to modify our curriculum in a way that will optimize and facilitate learning.
3D harnessing of light with 2.5D photonic crystals
Authors: Viktorovitch P. , Ben Bakir B. , Boutami S. , Leclercq J. Louis , Letartre X. , Rojo‐Romeo P. , Seassal C. , Zussy M. , Di Cioccio L. , Fedeli J.Marc
Published: September 2009

It is emphasized that two‐dimensional photonic crystals (2D PC) have not only a great potential for the development of 2D nanophotonics in the inplane waveguided configuration, but that they may also open the way to other brilliant developments, with an extension to out‐of‐plane operation, along a 2.5D nanophotonics approach. In this 2.5D approach, a 1D–2D high index contrast lateral structuration is combined with a 1D high index contrast vertical structuration, using multilayer membrane stacks including 1D–2D photonic crystal membranes, thus resulting in so‐called 2.5D PC. As a specific illustration of recent achievements along this approach, new families of VCSEL structures are presented.
Sharing the pie and distributing the reward: a case of bonus distribution among executives
Authors: Wedley W. C. , Choo E. U.
Published: September 2009

Relevant criteria can be identified and used to partition and disaggregate a project's overall impact value into separate components to be evaluated independently under each criterion. Criteria weights can then be used to distribute the benefit of the joint project to its contributors. There are different interpretations of the criteria weights in different methods of benefit sharing. Project team members are motivated by the distribution of benefits. Criteria weights with different interpretations can be used as part of management incentives in setting up the joint project. In this work, different AHP type models are analyzed for a hypothetical case of bonus distribution to key executives. The implications of appropriate interpretations of criteria weights and local priorities are examined. Other sharing methods are discussed and analyzed. The method of bonus sharing based on the overall priorities of the contributions of all contributors is shown to produce resulting bonus shares that are always proportional to the actual contributions of the executives in the sharing set. Copyright © 2009 John Wiley & Sons, Ltd.
Non‐discriminating criteria in the AHP: removal and rank reversal
Authors: Wijnmalen Diederik J. D. , Wedley William C.
Published: September 2009

A non‐discriminating criterion is defined as a criterion where the decision‐maker is indifferent among the alternatives. One would therefore expect the final rank order of the alternatives not to be affected by removing it. A previously published paper by Finan and Hurley (Comput. Oper. Res. 2002; 29: 1025–1030) showed that in the analytic hierarchy process removing such a criterion from a multilevel hierarchy can reverse rank. In this paper, we offer an explanation of this particular rank reversal phenomenon and show how it can be avoided. We do this by taking into account that there is a link between the normalization and weighting processes, which suggests adjusting appropriate weights when removing criteria. Further, we discuss whether a non‐discriminating criterion should be removed in the first place. Copyright © 2009 John Wiley & Sons, Ltd.
Correcting illegitimate rank reversals: proper adjustment of criteria weights prevent alleged AHP intransitivity
Authors: Wijnmalen Diederik J. D. , Wedley William C.
Published: September 2009

This note comments on a paper by Triantaphyllou (J. Multi‐Crit. Decis. Anal. 2001; 10: 11–25) that attempts to demonstrate new types of rank reversal that can occur with the analytic hierarchy process (AHP). He contends that the reversals are attributable to the various types of normalization that are used with the addition step in AHP synthesis. His paper goes on to suggest that the multiplicative AHP should be used instead. This note shows that the cause of the problem is another one: AHP's independence axiom, which prohibits adjusting the criteria weights when the set of alternatives or the type of normalization change. If the criteria weights are adjusted properly, none of the rank reversals will occur. Copyright © 2009 John Wiley & Sons, Ltd.
Outbreak of Progressive Inflammatory Neuropathy Following Exposure to Aerosolized Porcine Neural Tissue
Authors: DeAngelis Tracy M. , Shen Liang
Published: September 2009

In the fall of 2007, the Minnesota Department of Health was notified of 11 cases of an unexplained neurological illness, all linked to a pork processing plant, Quality Pork Processors, Inc., in Austin, MN. The cluster of workers had been experiencing similar symptoms, including fatigue, pain, numbness, and tingling in their extremities as well as weakness. The symptoms were described as more sensory than motor, and all patients had evidence of polyradiculoneuropathy with signs of nerve root irritation. An epidemiological investigation revealed that the only commonality between cases was their exposure to a pork brain extraction procedure involving compressed air. As relatives of the cases remained asymptomatic and all cultures for known pathogens were negative, the etiology of the syndrome seemed not to be infectious. Clinically, the syndrome was most akin to chronic inflammatory demyelinating polyneuropathy. Laboratory tests corroborated the clinical findings, revealing inflammation of peripheral nerves and nerve roots; however, these cases also had features clinically distinct from chronic inflammatory demyelinating polyneuropathy as well as laboratory testing revealing a novel immunoglobulin G immunostaining pattern. This suggested that the observed inflammation was the result of 1 or more unidentified antigens. This syndrome was ultimately dubbed progressive inflammatory neuropathy and was theorized to be an autoimmune reaction to aerosolized porcine neural tissue. Since the investigation's outset, 18 cases of progressive inflammatory neuropathy have been identified at the Minnesota pork processing plant, with 5 similar cases at an Indiana plant and 1 case at a Nebraskan plant. The plants in which cases have been identified have since stopped the use of compressed air in removing pork brains. All cases have stabilized or improved, with some requiring immunosuppressive and analgesic treatment. The study of progressive inflammatory neuropathy is ongoing, and the details of this investigation highlight the value of epidemiological principles in the identification and containment of outbreaks while researchers attempt to uncover the unique pathophysiology and potential etiology of the illness. Mt Sinai J Med 76:442–447, 2009. © 2009 Mount Sinai School of Medicine
Paradigm Shift in the Pathophysiology of Postmenopausal and Thyrotoxic Osteoporosis
Authors: Zaidi Mone , Iqbal Jameel , Blair Harry C. , Zallone Alberta , Davies Terry , Sun Li
Published: September 2009

Bone loss is an inevitable result of getting older in both sexes. This loss is accelerated in women in the early years following menopause and in both sexes with drugs and diseases, prominently hyperthyroidism. Postmenopausal osteoporosis and hyperthyroid osteoporosis, both of which are widely recognized clinical entities, have been thought to arise from low estrogen levels and high thyroid hormone levels, respectively. However, when estrogen declines, follicle‐stimulating hormone, an anterior pituitary hormone, rises. Likewise, when thyroid hormone levels rise in hyperthyroidism, thyroid‐stimulating hormone levels fall. We have used a complement of mouse genetic, pharmacological, and cell biological approaches to unravel a direct action of follicle‐stimulating hormone and thyroid‐stimulating hormone on bone remodeling and bone mass. Apart from establishing a novel pituitary‐bone axis of physiological significance, our studies challenge the existing 1‐hormone, 1‐disease paradigm in endocrinology and suggest that a plurality of hormonal disturbances involving pituitary hormones cause postmenopausal and hyperthyroid osteoporoses. New therapeutic targets thus emerge from these studies. Mt Sinai J Med 76:474–483, 2009. © 2009 Mount Sinai School of Medicine
The questionnaire for urinary incontinence diagnosis (QUID): Validity and responsiveness to change in women undergoing non‐surgical therapies for treatment of stress predominant urinary incontinence
Authors: Bradley Catherine S. , Rahn David D. , Nygaard Ingrid E. , Barber Matthew D. , Nager Charles W. , Kenton Kimberly S. , Siddiqui Nazema Y. , Abel Robert B. , Spino Cathie , Richter Holly E.
Published: September 2009

Aims

The Questionnaire for Urinary Incontinence Diagnosis (QUID), a 6‐item urinary incontinence (UI) symptom questionnaire, was developed and validated to distinguish stress and urge UI. This study's objective was to evaluate QUID validity and responsiveness when used as a clinical trial outcome measure.

Methods

Participants enrolled in a multi‐center trial of non‐surgical therapy (continence pessary, pelvic floor muscle training or combined) for stress‐predominant UI and completed baseline and 3‐month diaries, the Urinary Distress Inventory (UDI) and QUID. Data from all treatment groups were pooled. QUID internal consistency (Cronbach's α) and convergent/discriminant validity (Pearson correlations) were evaluated. Responsiveness to change was assessed with 3‐month score outcomes and distribution‐based measurements.

Results

Four hundred forty‐four women (mean age 50) were enrolled with stress (N = 200) and mixed (N = 244) UI; 344 had 3‐month data. Baseline QUID Stress and Urge scores (both scaled 0–15, larger values indicating worse UI) were 8.4 ± 3.2 and 4.5 ± 3.3, respectively. Internal consistency of QUID Total, Stress, and Urge scores was 0.75, 0.64 and 0.87, respectively. QUID Stress scores correlated moderately with UDI‐Stress scores (r = 0.68, P < 0.0001) and diary stress UI episodes (r = 0.41, P < 0.0001). QUID Urge scores correlated moderately with UDI‐Irritative scores (r = 0.68, P < 0.0001) and diary urge UI episodes (r = 0.45, P < 0.0001). Three‐month QUID Stress and Urge scores improved (4.1 ± 3.4 and 2.2 ± 2.7, both P < 0.0001). QUID Stress score effect size (1.3) and standardized response mean (1.2) suggested a large change after therapy.

Conclusion

The QUID has acceptable psychometric characteristics and may be used as a UI outcome measure in clinical trials. Neurourol. Urodynam. 29:727–734, 2010. © 2010 Wiley‐Liss, Inc.
Free riding in a multi‐channel supply chain
Authors: Bernstein Fernando , Song Jing‐Sheng , Zheng Xiaona
Published: September 2009

Free riding in a multichannel supply chain occurs when one retail channel engages in the customer service activities necessary to sell a product, while another channel benefits from those activities by making the final sale. Although free riding is, in general, considered to have a negative impact on supply chain performance, certain recent industry practices suggest an opposite view: a manufacturer may purposely induce free riding by setting up a high‐cost, customer service‐oriented direct store to allow consumers to experience the product, anticipating their purchase at a retail store. This article examines how the free riding phenomenon affects a manufacturer's supply chain structure decision when there are fixed plus incremental variable costs for operating the direct store. We consider factors such as the effort required to find and buy the product at a retail store after visiting the direct store, the existence of competing products in the market, and the extent of consumer need to obtain direct‐store service. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009
Transformational and transactional leadership styles, followers' positive and negative emotions, and performance in German nonprofit orchestras
Authors: Rowold Jens , Rohmann Anette
Published: September 2009

Although the transformational‐transactional leadership paradigm has received increased attention from the research community over the past two decades, the nonprofit sector has been largely neglected. This study provides information about the effectiveness of transformational and transactional leadership styles in the domain of German nonprofit orchestras, while exploring the role of emotions within these leadership styles. We examined musicians' perceptions of their orchestra conductors' leadership behaviors and related those behaviors to performance. Positive emotions were associated with both transactional and transformational leadership. Negative emotions partially mediated the influence of transformational leadership on performance. In combination, the results allow a more thorough and detailed understanding of effective leadership behavior in nonprofit organizations.
Nonprofit governance during organizational transition in voluntary associations
Authors: Kreutzer Karin
Published: September 2009

This explorative field study examines the governance challenges that voluntary associations face in the transition from an internal focus on members to the provision of services to mainly nonmembers. This transition is an important stage in the life cycle of many associations. A qualitative research design was used to study five Swiss patient organizations. This article describes the transition process in terms of five main management challenges: different target groups, self‐help group versus competence center, cooperation, fundraising, and transparency. It then examines the implications for four governance aspects that confront managers and board members: recruitment and selection of board members, tasks of the board, relationship between the board and managing director, and the role of the general assembly of members.
Post‐stroke fatigue: qualitative study of three focus groups
Authors: Flinn Nancy A. , Stube Jan E.
Published: September 2009

Fatigue affects many persons after cerebrovascular accident, particularly those with mild stroke. A qualitative methodology using focus groups with 19 community‐living post‐stroke survivors was utilized to explore the occupational impact of fatigue as communicated by the participants. Although self‐report of a small sample of the United States' post‐stroke population will have limitations in generalizability, this study identifies specific health‐related quality of life issues that can occur with post‐stroke fatigue. The participants felt unprepared for the fatigue phenomenon and struggled to adapt, with fatigue having a debilitating influence upon daily occupational performance and roles, including social participation, return to work, driving, reading and sleeping. The participants indicated that exercise (such as walking and water aerobics) and use of assistive technology were helpful strategies in reducing fatigue. The occupational performance and role impact identified by participants in this study can inform the design of effective occupational therapy interventions and further quantitative study of persons with post‐stroke fatigue. Copyright © 2009 John Wiley & Sons, Ltd.
Effect of an anionic monomer on the pickering emulsion polymerization stabilized by titania hydrosol
Authors: Song Xiaomei , Yin Guannan , Zhao Yongliang , Wang Haitao , Du Qiangguo
Published: September 2009

Polystyrene (PS) nanocomposite particles with high titania content are prepared by Pickering emulsion polymerization. A self‐made titania hydrosol modified by an anionic monomer sodium styrene sulfonate (NaSS) is used as a stabilizer and photocatalyst. The stability of the emulsion system is greatly improved by the electrostatic interaction between negatively charged NaSS and positively charged titania nanoparticles. The nanocomposite spheres with the diameter of around 120 nm are highly charged, indicating titania‐rich surfaces of latex particles. It is also proven by the field‐emission transmission electron microscope and field‐emission scanning electron microscope images. The well‐defined core‐shell structure of the obtained PS/titania composite particles is confirmed by the formation of fragile hollow titania nanospheres after thermogravimetric analysis tests. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5728–5736, 2009
Synthesis of hyperbranched poly(ether nitrile)s by one‐step polycondensation of an AB2 monomer
Authors: Jikei Mitsutoshi , Itoh Hideaki , Yoshida Norihiro , Inai Yosuke , Hayakawa Teruaki , Kakimoto Masa‐Aki
Published: September 2009

Hyperbranched poly(ether nitrile)s were prepared from a novel AB2 type monomer, 2‐chloro‐4‐(3,5‐dihydroxyphenoxy)benzonitrile, via nucleophilic aromatic substitution. Soluble and low‐viscous hyperbranched polymers with molecular weights upto 233,600 (Mw) were isolated. According to the 1H NMR and GPC data, the unique polymerization behavior was observed, which implies that the weight average molecular weight increased after the number average molecular weight reached plateau region. Model compounds were prepared to characterize the branching structure. Spectroscopic measurements of the model compounds and the resulting polymers, such as 1H, DEPT 13C NMR, and MS, strongly suggest that the ether exchange reaction and cyclization are involved in the propagation reaction. The side reactions would affect the unique polymerization behavior. The resulting polymers showed a good solubility in organic solvents similar to other hyperbranched aromatic polymers. The hydroxy‐terminated polymer was even soluble in basic water. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5835–5844, 2009
Low temperature polymerization of novel, monotropic liquid crystalline benzoxazines
Authors: Velez‐Herrera Pedro , Ishida Hatsuo
Published: September 2009

Cationic ring opening polymerization at a lower temperature range/faster polymerization than ordinary benzoxazine resins has been achieved without added initiators or catalysts via liquid crystalline (LC) benzoxazine resins. Faster polymerization is observed even above the liquid crystal forming temperature. The FTIR spectra show that opening of the oxazine ring occurs even at 110 °C generating phenolic groups that auto‐catalyzed the cationic polymerization of the monomer increasing the rate of polymerization. The newly formed H‐bonds inhibit the formation of LC phases after polymerization. Some of the monomers show nematic LC transitions upon cooling. None of them showed LC transitions during the heating cycle, exhibiting monotropic LC phases. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5871–5881, 2009
Grafting of polymer matrix to exfoliated montmorillonite nanoplatelets in nanocomposite film cast from soap‐free emulsion polymerized latex and its fortified mechanical properties
Authors: Lin Keng‐Jen , Weng Ting Hsiang , Lee Chia‐Hsin , Lin King‐Fu
Published: September 2009

Poly(methyl acrylate‐co‐methyl methacrylate) [P(MA‐co‐MMA)] nanocomposite film containing 1 wt % of montmorillonite (MMT) exhibited unusual higher ductility, higher strain recovery ratio after creep, and higher modulus and strength compared to neat P(MA‐co‐MMA) as they were cast from their individual latices fabricated by soap‐free emulsion polymerization. The fortified mechanical properties were attributed to the MgO components of exfoliated MMT nanoplatelets being grafted by P(MA‐co‐MMA) chains as verified by FTIR and XPS spectroscopies, which to the best of our knowledge is the first time in the literature providing the direct evidence for the polymer chains grafting onto the exfoliated MMT. TEM investigation of the stretched nanocomposite film revealed that the microcracks in the nanocomposite film appeared mainly in the bulk region of polymer matrix, implying that the interfacial strength between P(MA‐co‐MMA) and its grafted MMT nanoplatelets was higher than the cohesion strength of P(MA‐co‐MMA). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5891–5897, 2009