bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased new bone formation with a surface magnesium‐incorporated deproteinized porcine bone substitute in rabbit calvarial defects
Authors: Park Jin‐Woo , Ko Hyuk‐Jin , Jang Je‐Hee , Kang Hochang , Suh Jo‐Young
Published: January 2012

This study investigated the effects of magnesium ion (Mg) incorporation into the surface of deproteinized porcine cancellous bone in the bone healing of rabbit calvarial defects with the expectation of utilizing the integrin–ligand binding enhancement effect of Mg, and compared its bone healing capacity with that of untreated porcine cancellous bone and deproteinized bovine bone (Bio‐Oss). Hydrothermal treatment was performed to produce Mg‐incorporated porcine bone using an alkaline Mg‐containing solution. The surface morphology and chemical composition of the samples were investigated using scanning electron microscopy, energy‐dispersive X‐ray spectrometry, and X‐ray photoelectron spectroscopy. Defects 7 mm in diameter were created in the calvaria of 14 adult male New Zealand White rabbits and were filled with (1) untreated porcine bone (PB), (2) Bio‐Oss, and (3) Mg‐containing porcine bone (MG). The percentage of newly formed bone (NB%) was evaluated histomorphometrically at 2 and 4 weeks after implantation. Hydrothermal treatment resulted in a Mg‐containing surface in porcine bone covered with nanostructures ∼100 nm in size. The MG group supported better new bone formation compared with the other groups. Osteoconductive new bone formation was observed in the central defect area in the MG group at an early healing time‐point. Histomorphometric analysis revealed significantly greater NB% in the MG group when compared with the untreated PB and Bio‐Oss groups at 4 weeks (p < 0.05). The Mg‐incorporated porcine bone with surface nanostructures achieved rapid new bone formation in the osseous defects of rabbit calvaria compared with untreated xenografts of porcine and bovine origin. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Cytotoxicity and cellular uptake of lysozyme‐stabilized gold nanoparticles
Authors: Lee Yeonju , Geckeler Kurt E.
Published: January 2012

The particle size and surface properties of gold nanoparticles are critical factors for the interactions between nanoparticles and cells. To produce noncytotoxic gold nanoparticles, a straightforward method for the synthesis of gold nanoparticles designed involving the reduction and stabilization by a protein such as a lysozyme in conjunction with microwave irradiation. The cooperative combination of a lysozyme with a high affinity for metal ions and the microwave irradiation allowed to form biocompatible gold nanoparticles in an aqueous system. In addition, the cell toxicity and the cellular uptake pathways of the gold nanoparticles synthesized against mouse embryonic fibroblast NIH‐3T3 cells were studied and found to be taken up by receptor‐mediated endocytosis. In addition, the lysozyme‐stabilized gold nanoparticles are accumulated in the cytoplasm as well as the nucleus without any significant cytotoxicity. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
Subclavian and pulmonary artery steal phenomenon in a patient with isolated left subclavian artery and right aortic arch
Authors: Hayabuchi Yasunobu , Inoue Miki , Sakata Miho , Ohnishi Tatsuya , Kagami Shoji
Published: January 2012

We describe a patient with an isolated left subclavian artery associated with right aortic arch, patent ductus arteriosus, and ventricular septal defect. As the isolated left subclavian artery is supplied by the left vertebral artery in which blood flows in the retrograde direction, this anomaly is usually responsible for a congenital subclavian steal phenomenon. Atrophy of the left cerebral hemisphere and inverted left vertebral arterial flow were clearly depicted by echoencephalography in this patient, whose subclavian artery was connected to the main pulmonary artery by a patent ductus arteriosus. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2013.
Sonographic appearance of an advanced invasive mole and associated metastatic thrombus in the inferior vena cava
Authors: Okumura Maria , Fushida Koji , Pulcineli Vieira Francisco Rossana , Schultz Regina , Zugaib Marcelo
Published: January 2012

We present a case of an advanced invasive mole with a metastatic thrombus in the inferior vena cava in which sonography clearly showed vesicles in the myometrium, ovaries, and metastatic thrombus leading to a diagnosis of invasive mole rather than choriocarcinoma. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2013.
Decreased echogenicity of the embryo is correlated with absence of cardiac activity
Authors: Tan Sinan , İpek Ali , Levent Keskin Hüseyin , Karaoğlanoğlu Mustafa , Çiraci Saliha , Öztürk Hasan
Published: January 2012

Purpose:

The purpose of this study was to investigate whether the sonographic echogenicity of embryos is associated with cardiac activity in utero.

Methods:

The present study reviewed a total of 164 embryos having a gestational age between 6 and 8 weeks. These embryos were examined by transvaginal ultrasonography and a comparison of their echogenicity was made with respect to those of the placenta and the myometrium. Grade II embryos were less echogenic than the placenta or had similar echogenicity with the myometrium, whereas grade I embryos shared the same echogenicity as the placenta. In contrast, grade III embryos were less echogenic than the myometrium.

Results:

Most of the embryos with cardiac activity were detected to have grade II echogenicity (78/130, 60.0%), whereas the remaining embryos had grade I echogenicity (52/130, 40.0%). In contrast, most of the embryos without cardiac activity had grade III echogenicity (20/34, 58.8%), whereas the remaining embryos had either grade II (8/34, 23.5%) or grade I (6/34, 17.7%) echogenicity.

Conclusions:

Decreased echogenicity of embryos on grayscale ultrasound in the early first trimester is correlated with an absence of cardiac activity. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012.
Multi‐modal quantitative MRI investigation of brain tissue neurodegeneration in multiple sclerosis
Authors: Hasan Khader M. , Walimuni Indika S. , Abid Humaira , Wolinsky Jerry S. , Narayana Ponnada A.
Published: January 2012

Purpose:

To investigate the utility of multimodal quantitative MRI (qMRI) and atlas‐based methods to identify characteristics of lesion‐driven injury and neurodegeneration in relapsing remitting multiple sclerosis (RRMS).

Materials and Methods:

This work is health insurance portability and accountability act compliant. High resolution T1‐weighted, dual echo, and fluid‐attenuated inversion recovery and diffusion tensor MRI images were prospectively acquired on 68 RRMS patients (range, 25–58 years) and 68 age‐matched controls. The data were analyzed using standardized human brain atlas‐based tissue segmentation procedures to obtain regional volumes and their corresponding T2 relaxation times and DTI maps.

Results:

Group‐averaged brain atlas‐based qMRI maps of T2, fractional anisotropy and diffusivities are visually presented and compared between controls and RRMS. The analysis shows a widespread injury in RRMS. Atrophy of the corpus callosum (CC) was substantial in RRMS. The qMRI attributes of the neocortex in combination with the CC such as T2 and diffusivities were elevated and correlated with disability.

Conclusion:

Using a standardized multimodal qMRI acquisition and analyses that accounted for lesion distribution we demonstrate that cerebral pathology is widespread in RRMS. Our analysis of CC and neocortex qMRI metrics in relation to disability points to a neurodegenerative injury component that is independent from lesions. J. Magn. Reson. Imaging 2012;35:1300–1311. © 2012 Wiley Periodicals, Inc.
Are reclamo hunting seasons for the Spanish red‐legged partridge off the mark?
Authors: Vargas J. Mario , Duarte Jesus , Farfán Miguel Angel , Villafuerte Rafael , Fa John E.
Published: January 2012

The red‐legged partridge (Alectoris rufa) is abundant in a number of regions in Spain and one of the most commonly hunted small game species in the country. Partridge hunting generates substantial income in rural areas where agriculture is less profitable. A traditional hunting method, reclamo hunting, is currently under revision by the European Commission's (EC) Birds Directive because hunting may fall within the reproduction period of the species. So far, only limited data on the reproductive phenology of the species exist to inform a policy change. In this study, we present reproduction data for red‐legged partridges from 9 hunting estates in Andalusia during 1 year, and over 3 consecutive seasons from a control estate. We used direct nest and partridge chick covey observations to estimate 165 egg‐laying dates. We found significant differences between sites related to altitude during reproduction periods. Using our pooled data, we showed that reproduction occurred between the last 10 days in January and the middle of February; beyond 31 January we observed an exponential increase in birds reproduction. According to these data and current EC legislation, reclamo hunting should not extend beyond 31 January. © 2012 The Wildlife Society.
Real‐time guidance of thermal and ultrashort pulsed laser ablation in hard tissue using inline coherent imaging
Authors: Leung Ben Y.C. , Webster Paul J.L. , Fraser James M. , Yang Victor X.D.
Published: January 2012

Background and Objective

During tissue ablation, laser light can be delivered with high precision in the transverse dimensions but final incision depth can be difficult to control. We monitor incision depth as it progresses, providing feedback to ensure that material removal occurs within a localized target volume, reducing the possibility of undesirable damage to tissues below the incision.

Materials and Methods

Ex vivo cortical and cancellous bone was ablated using pulsed lasers with center wavelengths of 1,064 and 1,070 nm, while being imaged in real‐time using inline coherent imaging (ICI) at rates of up to 300 kHz and axial resolution of ∼6 µm. With real‐time feedback, laser exposure was terminated before perforating into natural inclusions of the cancellous bone and verified by brightfield microscopy of the crater cross‐sections accessed via side‐polishing.

Results

ICI provides direct information about incision penetration even in the presence of intense backscatter from the pulsed laser and plasma emissions. In this study, ICI is able to anticipate structures 176 ± 8 µm below the ablation front with signal intensity 9 ± 2 dB above the noise floor. As a result, the operator is able to terminate exposure of the laser sparing a 50 µm thick layer of bone between the bottom of the incision to a natural inclusion in the cancellous bone. Versatility of the ICI system was demonstrated over a wide range of light–tissue interactions from thermal regime to direct solid‐plasma transition.

Conclusions

ICI can be used as non‐contact real‐time feedback to monitor the depth of an incision created by laser ablation, especially in heterogeneous tissue where ablation rate is less predictable. Furthermore, ICI can image below the ablation front making it possible to stop laser exposure to limit unintentional damage to subsurface structures such as blood vessels or nervous tissue. Lasers Surg. Med. 44:249–256, 2012. © 2012 Wiley Periodicals, Inc.
High resolution spectroscopic imaging of GABA at 3 Tesla
Authors: Zhu He , Edden Richard A. E. , Ouwerkerk Ronald , Barker Peter B.
Published: January 2012

A spin echo‐based MRSI sequence was developed to acquire edited spectra of γ‐aminobutyric acid in an entire slice. Water and lipid signals were suppressed by a dual‐band presaturation sequence, which included integrated outer volume suppression pulses for additional lipid suppression. Experiments in three normal volunteers were performed at 3 T using a 32‐channel head coil. High signal‐to‐noise ratio spectra and metabolic images of γ‐aminobutyric acid were acquired from nominal 4.5 cm3 voxels (estimated actual voxel size 7.0 cm3) in a scan time of 17 min. The sequence is also expected to co‐edit homocarnosine and macromolecules, giving a composite γ‐aminobutyric acid+ resonance. The γ‐aminobutyric acid+ to water ratio was measured using a companion water MRSI scan and was found to correlate linearly with the % gray matter (GM) of each voxel (γ‐aminobutyric acid+/water = (1.5 × GM + 3.2) × 10−5, R = 0.27), with higher γ‐aminobutyric acid+ levels in gray matter compared with white. In conclusion, high signal‐to‐noise ratio γ‐aminobutyric acid‐MRSI is possible at 3 T within clinically feasible scan times. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.
A fully coupled elastic–plastic hydromechanical model for compacted soils accounting for clay activity
Authors: Vecchia Gabriele Della , Romero Enrique
Published: January 2012

A constitutive model, accounting for multiphase and multiscale coupling, is proposed for the water retention domain and the stress–strain response of compacted clayey soils. The model is based on a conceptual interpretation of the microfabric evolution of compacted soils along generalised hydromechanical paths, detected by means of mercury intrusion porosimeter tests. Multiphase coupling is provided by the mutual interaction between the mechanical and the hydraulic states. Multiscale coupling is introduced by a measure of the size of the aggregates, which influences both the retention and the stress–strain response, in the phenomenological constitutive equations. Model capabilities are verified by comparison with relevant experimental data from laboratory tests on compacted Boom clay and other selected experimental data on different compacted clayey soils. Copyright © 2012 John Wiley & Sons, Ltd.
A random solid‐porous model to simulate the retention curves of soils
Authors: Horta Jaime , Rojas Eduardo , Pérez‐Rea María L. , López Teresa , Zaragoza Juan B.
Published: January 2012

This paper describes a random solid‐porous model capable of simulating the structure of porous materials. To this purpose, the grain and pore size distributions as well as the void ratio of the material are required. Solids and pores are distributed at random in the model's space according to a size strategy. Herein, the model is used to simulate the retention curves of soils. The Laplace equation is used to determine the size of the pores able to saturate or dry during a wetting or drying process, respectively. The continuous path principle is used to define those elements that effectively saturate or dry during these processes. With this procedure, it is possible to simulate the main retention curves as well as the scanning curves during wetting–drying cycles. Some experimental results reported in the international literature have been used to test the model. This model can be enhanced to study the mechanical behavior of unsaturated soils. Copyright © 2012 John Wiley & Sons, Ltd.
Influence of socioeconomic factors on the adherence of alendronate treatment in incident users in Norway
Authors: Devold Helene M. , Furu Kari , Skurtveit Svetlana , Tverdal Aage , Falch Jan A. , Sogaard Anne Johanne
Published: January 2012

Purpose

To examine whether socioeconomic factors influence adherence to alendronate drug treatment among incident users in Norway during 2005–2009.

Methods

The study included 7610 incident alendronate users in 2005 (40–79 years), followed until 31 December 2009. Mean age was 66.6 years, and 86.7% of the patients were women. Data were drawn from the Norwegian Prescription Database and linked to marital status, education and income. Adherence was measured by the medication possession ratio (MPR). MPR was defined as the number of dispensed defined daily doses divided by the number of days each patient was included in the study. A patient was adherent if MPR ≥ 80%. ORs with 95%CI were estimated using logistic regression.

Results

Among all patients, 45.5% was adherent throughout 4.2 years. A slightly higher proportion of women than men were adherent. Adjusted for all covariates, women aged 70–79 years had an OR of 1.27 (95%CI 1.10–1.45) for adherence compared with those 40–59 years. In women, high household income predicted adherence of alendronate use. In men, a middle educational level compared with a low level, predicted adherence (adjusted OR = 1.47 (95%CI 1.10–1.96)). After adjustments, previous marriage reduced the odds of being adherent compared with present marriage, in both men and women.

Conclusions

In women, the most important factors for being adherent were high age and high income. In men, a middle educational level predicted adherence. Previous marriage reduced the odds of being adherent in both women and men. Copyright © 2012 John Wiley & Sons, Ltd.
Energy pay‐back time: methodological caveats and future scenarios
Authors: Raugei Marco
Published: January 2012

Energy pay‐back time (EPBT) has almost universally been adopted as the indicator of choice to express the energy performance of photovoltaics (PV). In this paper, an in‐depth review of the methodology and all underlying assumptions and conventions is presented. A prospective analysis of the potential evolution of the EPBT of PV over the next four decades is then performed, assuming optimistic grid penetration figures and taking into account expected technological improvements. Results show that combining the two opposing effects of a reduction in cumulative energy demand for PV manufacturing and an increase in grid efficiency will likely result in severely limited reductions, or even possible increases, in the EPBT of PV. This is entirely due to how EPBT is operationally defined, and it has nothing to do with the actual energy performance of PV in the future. Copyright © 2012 John Wiley & Sons, Ltd.
BCAR1 expression improves prediction of biochemical reccurence after radical prostatectomy
Authors: Fromont Gaelle , Rozet François , Cathelineau Xavier , Ouzzane Adil , Doucet Laurent , Fournier Georges , Cussenot Olivier
Published: January 2012

BACKGROUND

Because prostate cancer exhibits a great variability in clinical outcome, biomarkers that can be used in daily practice are needed to better stratify patients into prognostic groups. Since steroid hormones play a central role in the development and progression of prostate cancer, we aimed to analyze in a matched nested case–control study the value of molecules involved in steroid signaling, to predict recurrence after radical prostatectomy, independently from standard prognostic tools.

METHODS

Among 1,200 patients treated by radical prostatectomy with negative margins with at least 4 years follow‐up, 121 prostate cancers with biochemical relapse were matched after pathological reassessment with 121 cancers with identical clinicopathological features but without relapse. Immunohistochemistry was performed on tissue microarrays, using antibodies directed against molecules involved in androgen and estrogen signaling, including hormone receptors, enzymes (such as the five alpha reductases 1,2 and 3, aromatase, alpha‐keto reductase 1C3 and squalene epoxidase), the breast cancer antiestrogen resistance 1 (BCAR1), and the proliferation marker Ki67.

RESULTS

The median follow‐up for patients without recurrence was 7 years. Both cell proliferation and BCAR1 expression were significantly associated with biochemical relapse, in univariate and multivariate analysis. In subgroup analysis, the sole predictive marker in patients with well‐differentiated prostate cancer was BCAR1 (P = 0.004), whereas only proliferation (P = 0.001) was significantly associated with relapse in less‐differentiated prostate cancer patients.

CONCLUSIONS

BCAR1 is an independent predictor of recurrence after radical prostatectomy for “low risk” prostate cancer. The use of this biomarker may enable more individualized treatment approaches. Prostate 72:1359–1365, 2012. © 2012 Wiley Periodicals, Inc.
Vision‐based absolute navigation for descent and landing
Authors: Van Pham Bach , Lacroix Simon , Devy Michel
Published: January 2012

Future space exploration missions such as Mars sample return or the lunar lander mission require precise information about the lander position during the descent and landing steps. This article presents a solution, Landstel, that exploits on‐board vision to localize the lander with respect to orbital imagery. The algorithm is based on the geometric repartition of surface landmarks to match descent images with orbital images. It is designed to be robust to illumination variations, to be independent of the presence of specific features on the surface, and to have low memory and processing power requirements. Overall absolute localization is achieved by the integration of Landstel with inertial navigation or with visual odometry, according to a loose fusion scheme. Extensive results with simulated and real data validate the proposed approach, and show that it works well even under difficult conditions where the landmark repeatability rate drops to 10%. © 2012 Wiley Periodicals, Inc.
Analyzing Epistemological Considerations Related to Diversity: An Integrative Critical Literature Review of Family Literacy Scholarship
Authors: Compton‐Lilly Catherine , Rogers Rebecca , Lewis Tisha Y.
Published: January 2012

The purpose of this review of family literacy scholarship was to examine the epistemologies underlying both family studies and reviews of family literacy studies. We were especially concerned with those epistemological issues related to the cultural, class, racial, gender, ethnic, and linguistic diversity of people served by family literacy programs. Our rationale for focusing on epistemology and diversity was that research on family literacy has often been framed in ways reflective of epistemological views of diversity, including such binaries as ‘strengths and deficits,’ ‘literate and illiterate,’ and ‘home‐school match and mismatch,’ among others. We searched major electronic databases for reviews of family literacy research and then employed bibliographic branching to identify other reviews yielding 273 reviews of which 213 were substantive. We subjected the 213 substantive reviews to an analytic review template to identify the degree to which diversity was addressed and how it was addressed. We conducted citation coding to identify major citations in each review. We then identified a set of comprehensive edited volumes and subjected the introductions, tables of contents, list of contributors, and references to diversity to a critical discourse analysis emphasizing underlying epistemologies. Findings included the dominance of White women scholars in family literacy research, the incorporation of both modernist and postmodernist epistemologies, and the absence of substantive concern with diversity in a majority of family literacy studies. Findings also showed that more recent reviews were less focused on modernist visions of family literacy as a means to address social problems and more focused on relationships between home and school literacies and the diversity of literacy practices found in homes. In addition, we found that recent reviews showed an increased focus on international and transnational contexts as well as literacy within specific local communities. We discuss these findings as reflecting the complex and diverse environments in which family literacy takes place with their multiple goals. We also discuss the importance of making underlying epistemological assumptions visible so that complexities and contradictions can be acknowledged and addressed.
Conditional estimation after a two‐stage diagnostic biomarker study that allows early termination for futility
Authors: Koopmeiners Joseph S. , Feng Ziding , Pepe Margaret Sullivan
Published: January 2012

Many biomarkers identified in marker discovery are shown to have inadequate performance in validation studies. This motivates the use of group sequential designs that allow early termination for futility. However, an option for early termination will lead to biased estimates for studies that reach full enrollment. We propose conditional estimators and confidence intervals that correct for this bias assuming that an unadjusted estimator exists that has an independent increments covariance structure. The proposed estimators and confidence intervals are applied to conditional estimation of the receiver operating characteristic curve and the positive predictive value curve after a two‐stage study that allows early termination for futility, and their performance is evaluated by simulation. Copyright © 2012 John Wiley & Sons, Ltd.
First error bounds for the porous media approximation of the Poisson‐Nernst‐Planck equations
Authors: Schmuck M.
Published: January 2012

We study the well‐accepted Poisson‐Nernst‐Planck equations modeling transport of charged particles. By formal multiscale expansions we rederive the porous media formulation obtained by two‐scale convergence in [42, 43]. The main result is the derivation of the error which occurs after replacing a highly heterogeneous solid‐electrolyte composite by a homogeneous one. The derived estimates show that the approximation errors for both, the ion densities quantified in L2‐norm and the electric potential measured in H1‐norm, are of order O(s1/2).
Enzymatic Production of Monoacylglycerols (MAG) and Diacylglycerols (DAG) from Fish Oil in a Solvent‐Free System
Authors: Feltes Maria Manuela Camino , Villeneuve Pierre , Baréa Bruno , Barouh Nathalie , de Oliveira J. Vladimir , de Oliveira Débora , Ninow Jorge Luiz
Published: January 2012

Mono‐ (MAG) and diacylglycerols (DAG) are of nutritional interest. MAG and DAG containing eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were produced in a solvent‐free system via glycerolysis of menhaden oil catalyzed by Novozym 435. The effect of the molar ratio of glycerol to oil, enzyme concentration, and reaction temperature on MAG and DAG production was assessed. The optimal temperature was in the range of 55–70 °C for production of both acylglycerols. The increase in the substrates molar ratio led to a decrease in MAG and DAG content. The enzyme concentration was fixed at the lowest level evaluated (5%, by weight of substrates). High content of MAG (25% by weight) and DAG (41% by weight) containing, respectively, 12.46% EPA and 11.16% DHA, and 14.57% EPA and 13.70% DHA, were produced after 24 h at 70 °C, with 5% of lipase (by weight of substrate) and a glycerol‐to‐oil molar ratio of 1:1. For this reaction, a molar triacylglycerol (TAG) conversion of about 60% was achieved at equilibrium (10 h).
Un accident de travail peu ordinaire: embrochage de la verge par une esquille de bois
Authors: Moby Mpah E. H. , Atemkeng Tsatedem F. , Sala Beyeme T. , Fouda P. J. , Angwafo F.
Published: January 2012

Les auteurs rapportent une observation d’une plaie de la verge par embrochage d’une esquille de bois lors de l’activité quotidienne d’un menuisier. Le patient a été reçu trois heures après l’accident de travail. L’esquille de bois avait transpercé la verge de part en part, avec arrêt au niveau de la cuisse gauche. L’exploration chirurgicale a retrouvé une plaie d’environ 1,5 × 3 cm des corps caverneux, sans atteinte visible de l’urètre, et une effraction du muscle quadriceps. Le risque de dysfonction érectile secondaire au traumatisme des corps caverneux a été évoqué.
Suspensions with a tunable effective viscosity: a numerical study
Authors: Jibuti L. , Rafaï S. , Peyla P.
Published: January 2012

In this paper, we conduct a numerical investigation of sheared suspensions of non-colloidal spherical particles on which a torque is applied. Particles are mono-dispersed and neutrally buoyant. Since the torque modifies particle rotation, we show that it can indeed strongly change the effective viscosity of semi-dilute or even more concentrated suspensions. We perform our calculations up to a volume fraction of 28 %. And we compare our results to data obtained at 40 % by Yeo and Maxey (Phys. Rev.E, vol. 81, 2010, p. 62501) with a totally different numerical method. Depending on the torque orientation, one can increase (decrease) the rotation of the particles. This results in a strong enhancement (reduction) of the effective shear viscosity of the suspension. We construct a dimensionless number$\Theta $which represents the average relative angular velocity of the particles divided by the vorticity of the fluid generated by the shear flow. We show that the contribution of the particles to the effective viscosity can be suppressed for a given and unique value of$\Theta $independently of the volume fraction. In addition, we obtain a universal behaviour (i.e. independent of the volume fraction) when we plot the relative effective viscosity divided by the relative effective viscosity without torque as a function of$\Theta $. Finally, we show that a modified Faxén law can be equivalently established for large concentrations.
Bilateral maxillary mucoceles: an unusual presentation of cystic fibrosis
Authors: Qureishi A , Lennox P , Bottrill I
Published: January 2012

Objective:

We report a rare case of bilateral maxillary mucoceles. This was the primary presentation in a child with an underlying diagnosis of cystic fibrosis.

Case report:

A five-month-old infant presented with isolated symptoms of nasal congestion. Initial examination and investigation with computed tomography identified the cause to be bilateral maxillary mucoceles. The child was investigated for cystic fibrosis and found to be positive. Given the young age and anatomy, a modified surgical approach was used to treat the mucoceles, comprising endoscopic and bilateral uncapping of the maxillary mucocele, uncinectomy, and middle meatal antrostomy. The child was then followed up with appropriate treatment for cystic fibrosis. At six-week follow up, there was no recurrence of symptoms.

Conclusion:

Maxillary mucoceles are extremely rare but can present in patients with chronic sinusitis or cystic fibrosis. To our knowledge, there are no prior reports of this condition being the primary indicator of underlying cystic fibrosis in the absence of upper respiratory tract symptoms. Doctors should be aware that mucoceles can present in very young individuals and may indicate an underlying diagnosis of cystic fibrosis. A high index of clinical suspicion will avoid delays in diagnosis and long-term management.
Measuring Subjective Wellbeing: Recommendations on Measures for use by National Governments
Authors: DOLAN PAUL , METCALFE ROBERT
Published: January 2012

Governments around the world are now beginning to seriously consider the use of measures of subjective wellbeing (SWB) – ratings of thoughts and feelings about life – for monitoring progress and for informing and appraising public policy. The mental state account of wellbeing upon which SWB measures are based can provide useful additional information about who is doing well and badly in life when compared to that provided by the objective list and preference satisfaction accounts. It may be particularly useful when deciding how best to allocate scarce resources, where it is desirable to express the benefits of intervention in a single metric that can be compared to the costs of intervention. There are three main concepts of SWB in the literature – evaluation (life satisfaction), experience (momentary mood) and eudemonia (purpose) – and policy-makers should seek to measure all three, at least for the purposes of monitoring progress. There are some major challenges to the use of SWB measures. Two related and well-rehearsed issues are the effects of expectations and adaptation on ratings. The degree to which we should allow wellbeing to vary according to expectations and adaptation are vexing moral problems but information on SWB can highlight what difference allowing for these considerations would have in practice (e.g. in informing prioiritisation decisions), which can then be fed into the normative debate. There are also questions about precisely what attention should be drawn to in SWB questions and how to capture the ratings of those least inclined to take part in surveys, but these can be addressed through more widespread use of SWB. We also provide some concrete recommendations about precisely what questions should be asked in large-scale surveys, and these recommendations have been taken up by the Office of National Statistics in the UK and are being looked at closely by the OECD.
Residential proximity of nearest child and older adults’ receipts of informal support transfers in Barbados
Authors: QUASHIE NEKEHIA , ZIMMER ZACHARY
Published: January 2012

This study assesses the probability that an older person in Bridgetown, Barbados receives financial, functional and/or material support from their adult children according to the proximity of their nearest child, adjusting for demographic and socio-economic factors. As in many countries of the developing world, older Barbadians receive much of their support from adult children. Population ageing, smaller family sizes and high rates of out-migration may be placing stress on systems of formal and informal support within the country. Yet, very little research has examined determinants of support within the Caribbean let alone Barbados, one of the most rapidly ageing countries in the region. Data (N = 1,248) come from the 2000 Pan American Health Organization Survey on Health, Well-being and Ageing in Latin America and the Caribbean (SABE). Multivariate logistic regression analyses highlight the overwhelming importance of co-residence in the receipt of informal support transfers. Although there is a lower probability of receiving support as distance to nearest child increases, several indicators of vulnerability, such as having a disability, increases support probabilities among those whose nearest children live outside the neighbourhood. The results have implications for current and future cohorts of older adults in the region given the combination of declining fertility, persistent migration and population ageing within a broader context of social protection systems across the region.
Principles for code choice in the foreign language classroom: A focus on grammaring
Authors: Levine Glenn S.
Published: January 2012

The social and cultural ‘turn’ in language education of recent years has helped move language teaching and curriculum design away from many of the more rigid dogmas of earlier generations, but the issue of the roles of the learners’ first language (L1) in language pedagogy and classroom interaction is far from settled. Some follow a strict ‘exclusive target language’ pedagogy, while others ‘resort to’ the use of the L1 for a variety of purposes (see ACTFL 2008). Underlying these competing views is the perspective of the L1 as an impediment to second language learning. Following sociocultural theory and ecological perspectives of language and learning and based on the findings of research on classroom code-switching and code choice, this paper lays out an approach to the language classroom as a multilingual social space in which learners and teacher study, negotiate, and co-construct code choice norms toward the dynamic, creative, and pedagogically effective use of both the target language and the learners’ L1(s). Learner use of the L1 for the purpose of grammatical or lexical learning is also considered, and some examples for instruction are offered.
Process of optimisation for a 4 DOF tele-echography robot
Authors: Nouaille L. , Vieyres P. , Poisson G.
Published: January 2012

This paper deals with processes of optimisation for the design of a four degree-of-freedom robot dedicated to remote ultrasound tele-echography. This robot is designed to track the medical gestures of a remote expert moving an ultrasound probe. The goal is to optimise the kinematic structure by fixing the geometric parameters; these have a significant role in robot configuration singularities, with respect to current medical gestures and mechanism compactness. After choosing a dedicated kinematic structure, several optimisations are presented. Then an optimal choice of geometrical parameters of a global function in relation with kinematic performance indices and compactness is proposed. This robot is soon to be used in the experimental medical phase of the Prosit project.
Singularity analysis of the H4 robot using Grassmann–Cayley algebra
Authors: Amine Semaan , Caro Stéphane , Wenger Philippe , Kanaan Daniel
Published: January 2012

This paper extends a recently proposed singularity analysis method to lower-mobility parallel manipulators having an articulated nacelle. Using screw theory, a twist graph is introduced in order to simplify the constraint analysis of such manipulators. Then, a wrench graph is obtained in order to represent some points at infinity on the Plücker lines of the Jacobian matrix. Using Grassmann–Cayley algebra, the rank deficiency of the Jacobian matrix amounts to the vanishing condition of the superbracket. Accordingly, the parallel singularities are expressed in three different forms involving superbrackets, meet and join operators, and vector cross and dot products, respectively. The approach is explained through the singularity analysis of the H4 robot. All the parallel singularity conditions of this robot are enumerated and the motions associated with these singularities are characterized.
From stable walking to steering of a 3D bipedal robot with passive point feet
Authors: Shih Ching-Long , Grizzle J. W. , Chevallereau Christine
Published: January 2012

This paper exploits a natural symmetry present in a 3D robot in order to achieve asymptotically stable steering. The robot under study is composed of 5-links and unactuated point feet; it has 9 DoF (degree-of-freedom) in the single-support phase and six actuators. The control design begins with a hybrid feedback controller that stabilizes a straight-line walking gait for the 3D bipedal robot. The closed-loop system (i.e., robot plus controller) is shown to be equivariant under yaw rotations, and this property is used to construct a modification of the controller that has a local, but uniform, input-to-state stability (ISS) property, where the input is the desired turning direction. The resulting controller is capable of adjusting the net yaw rotation of the robot over a step in order to steer the robot along paths with mild curvature. An interesting feature of this work is that one is able to control the robot's motion along a curved path using only a single predefined periodic motion.
UPDATING CLINICAL PRACTICE RECOMMENDATIONS: IS IT WORTHWHILE AND WHEN?
Authors: Lyratzopoulos Georgios , Barnes Steven , Stegenga Heather , Peden Suzi , Campbell Bruce
Published: January 2012

Background: Keeping clinical practice recommendations up-to-date with a continually evolving evidence base presents challenges. Resources required to update recommendations compete with those needed to evaluate newer treatments.

Methods: We describe an approach developed by the UK National Institute for Health and Clinical Excellence (NICE) for updating clinical practice recommendations for new interventional procedures and we evaluate relevant initial experience of using this system. Depending on whether evidence for a procedure is judged adequate or inadequate for safety and efficacy, use in clinical practice is usually recommended with either “normal” or “special” arrangements for patient consent, data collection and institutional oversight, respectively. We examined whether differences in the state of the evidence at the initial and the updated appraisal of procedures were associated with changed recommendations.

Results: Since 2008, updating of recommendations focuses on procedures with initially inadequate evidence. “Special arrangements” recommendations about eleven procedures were updated after 3.3–6.5 years (median, 5.3 years), and recommendations for six were changed to “normal arrangements.” Overall, procedures with changed (“special-to-normal”) recommendations had a greater increase in the number of patients included in observational studies published since the initial guidance.

Conclusions: Procedures with changed (“special-to-normal”) recommendations generally had greater increases in their evidence base. Although uncertainties about optimal methods for keeping evidence-based recommendations up-to-date remain, this experience should be useful to policy makers in developing processes for prioritizing scarce resources for updating clinical practice recommendations. Further studies are needed about the value placed on “updated” recommendations by clinicians, policy-makers, and patients.
Generating example contexts to help children learn word meaning
Authors: LIU LIU , MOSTOW JACK , AIST GREGORY S.
Published: January 2012

This article addresses the problem of generating good example contexts to help children learn vocabulary. We describe VEGEMATIC, a system that constructs such contexts by concatenating overlapping five-grams from Google's N-gram corpus. We propose and operationalize a set of constraints to identify good contexts. VEGEMATIC uses these constraints to filter, cluster, score, and select example contexts. An evaluation experiment compared the resulting contexts against human-authored example contexts (e.g., from children's dictionaries and children's stories). Based on rating by an expert blind to source, their average quality was comparable to story sentences, though not as good as dictionary examples. A second experiment measured the percentage of generated contexts rated by lay judges as acceptable, and how long it took to rate them. They accepted only 28% of the examples, but averaged only 27 seconds to find the first acceptable example for each target word. This result suggests that hand-vetting VEGEMATIC's output may supply example contexts faster than creating them manually.
Modeling Sociocultural phenomena in discourse
Authors: BROADWELL GEORGE AARON , STROMER-GALLEY JENNIFER , STRZALKOWSKI TOMEK , SHAIKH SAMIRA , TAYLOR SARAH , LIU TING , BOZ UMIT , ELIA ALANA , JIAO LAURA , WEBB NICK
Published: January 2012

In this paper, we describe a novel approach to computational modeling and understanding of social and cultural phenomena in multi-party dialogues. We developed a two-tier approach in which we first detect and classify certain sociolinguistic behaviors, including topic control, disagreement, and involvement, that serve as first-order models from which presence the higher level social roles, such as leadership, may be inferred.
Stability and turbulence in the atmospheric boundary layer: A comparison of remote sensing and tower observations
Authors: Friedrich Katja , Lundquist Julie K. , Aitken Matthew , Kalina Evan A. , Marshall Robert F.
Published: January 2012

When monitoring winds and atmospheric stability for wind energy applications, remote sensing instruments present some advantages to in‐situ instrumentation such as larger vertical extent, in some cases easy installation and maintenance, measurements of vertical humidity profiles throughout the boundary layer, and no restrictions on prevailing wind directions. In this study, we compare remote sensing devices, Windcube lidar and microwave radiometer, to meteorological in‐situtower measurements to demonstrate the accuracy of these measurements and to assess the utility of the remote sensing instruments in overcoming tower limitations. We compare temperature and wind observations, as well as calculations of Brunt‐Väisälä frequency and Richardson numbers for the instrument deployment period in May–June 2011 at the U.S. Department of Energy National Renewable Energy Laboratory's National Wind Technology Center near Boulder, Colorado. The study reveals that a lidar and radiometer measure wind and temperature with the same accuracy as tower instruments, while also providing advantages for monitoring stability and turbulence. We demonstrate that the atmospheric stability is determined more accurately when the liquid‐water mixing ratio derived from the vertical humidity profile is considered under moist‐adiabatic conditions.
A chain of magnetic flux ropes in the magnetotail of Mars
Authors: Eastwood J. P. , Videira J. J. H. , Brain D. A. , Halekas J. S.
Published: January 2012

The interaction of Mars with the solar wind leads to the formation of a magnetotail through which significant quantities of planetary plasma are transported. Of particular interest is the extent to which this plasma transport could be affected by magnetotail dynamics, for example by magnetic reconnection and flux rope formation. Here we show observations from Mars Global Surveyor of multiple flux ropes observed in Mars' magnetotail current sheet. A chain of at least three flux ropes is observed; based on the geometry of the encounter, the flux ropes are all being ejected in the same direction from a single dominant site and modeling shows that at least two of the flux ropes are close to being in a force free condition. Given geometrical considerations, it is likely that the flux ropes are generated sequentially rather than simultaneously, suggesting periodic generation via secondary instabilities at the reconnection site.
Slow rupture of frictional interfaces
Authors: Bar Sinai Yohai , Brener Efim A. , Bouchbinder Eran
Published: January 2012

The failure of frictional interfaces and the spatiotemporal structures that accompany it are central to a wide range of geophysical, physical and engineering systems. Recent geophysical and laboratory observations indicated that interfacial failure can be mediated by slow slip rupture phenomena which are distinct from ordinary, earthquake‐like, fast rupture. These discoveries have influenced the way we think about frictional motion, yet the nature and properties of slow rupture are not completely understood. We show that slow rupture is an intrinsic and robust property of simple non‐monotonic rate‐and‐state friction laws. It is associated with a new velocity scalecmin, determined by the friction law, below which steady state rupture cannot propagate. We further show that rupture can occur in a continuum of states, spanning a wide range of velocities from cminto elastic wave‐speeds, and predict different properties for slow rupture and ordinary fast rupture. Our results are qualitatively consistent with recent high‐resolution laboratory experiments and may provide a theoretical framework for understanding slow rupture phenomena along frictional interfaces.
Statistical investigation of horizontal propagation of gravity waves in the ionosphere over Europe and South Africa
Authors: Chum J. , Athieno R. , Baše J. , Burešová D. , Hruška F. , Laštovička J. , McKinnell L. A. , Šindelářová T.
Published: January 2012

A statistical investigation into the horizontal propagation of ∼8–30 min gravity waves (GWs) in the ionosphere over a 1 year period from June 2010 to May 2011 is presented. The GWs were observed by multipoint continuous Doppler sounding systems installed in the Czech Republic and in the Western Cape, South Africa. Measurements of GW propagation in the ionosphere over South Africa have never been presented before. Simultaneous measurements from nearby ionosondes made it possible to estimate the height of the GW observations and show that the analyzed GWs propagated at altitudes from ∼150 to ∼250 km. The analyzed waves were mainly observed after sunrise and around sunset. Our statistical study shows that the analyzed GWs propagated with horizontal velocities from ∼70 to 250 m/s. The average observed horizontal velocities were ∼100 m/s in the local summer and 125–150 m/s in the local winter. The waves propagated approximately poleward in the local summer, whereas roughly equatorward propagation was observed in the local winter. Westward propagation was rarely observed in the Czech Republic, and eastward (southeast) propagation was seldom observed in South Africa. A comparison with neutral wind velocities shows that the analyzed GWs propagated approximately against the neutral winds calculated by the HWM07 model. The estimated horizontal wavelengths of the analyzed waves were ∼100–300 km.