bluuebunny/crossref_metadata_2025 huggingface dataset:
High bandgap dielectrics for antireflective coating in silicon solar cells by reactive ion sputtering
Authors: Kaminski P. M. , Bass K. , Claudio G.
Published: March 2011

High bandgap materials have recently attracted a lot of interest for their potential application in photovoltaics (PV). Aluminium nitride (AlNx) is a potential candidate for the passivation and antireflective coating on silicon solar cells. AlNx thin films have been deposited by a remote plasma deposition system HiTUS (High Target Utilisation Sputtering). The AlNx thin films were grown by reactive sputtering from an aluminium target in a N2 atmosphere, negating the use of silane gas commonly used in PECVD deposition. PC1D simulations have been performed to calculate the best thickness for an antireflective coating for silicon wafers. Several depositions have been performed at different substrate temperatures. Photo conductive measurements by a WCT‐100 were performed on silicon wafer after each thermal process to measure the effective minority carrier lifetime of p‐type crystalline silicon wafer boron doped 〈100〉. Reflectance measurements were performed for samples prepared at different bias and flow gas ratios. Results show that the coating provides reflection reduction to levels below 5% for samples with a thickness of 70 nm. An increase in carrier lifetime has been observed for AlN deposited at high temperature. Annealing at 400 °C has been shown to increase carrier lifetime to 12 µs compared to 7 µs, suggesting the potential of AlN for silicon passivation and an alternative antireflective coating (ARC) to silicon nitride. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Atomic layer deposition reactor for fabrication of metal oxides
Authors: Kolanek Krzysztof , Tallarida Massimo , Michling Marcel , Karavaev Konstantin , Schmeisser Dieter
Published: March 2011

We developed an ultra high vacuum (UHV) compatible atomic layer deposition (ALD) reactor for studying the growth of metal oxides. The compatibility of the ALD reactor with the UHV system allows the use of surface sensitive techniques for characterizing the substrate/thin film complex after each ALD cycle. For investigation of the growth of metal oxides we used synchrotron radiation X‐ray photoelectron spectroscopy, UHV atomic force microscopy and a combined system consisting of electron energy loss spectroscopy and ultraviolet photoelectron spectroscopy. The samples were analyzed after each ALD cycle, composed of the subsequent exposure of the surface to metal oxides precursors and H2O (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The choice of the right electron range to connect with uniform generation shape in modelling EBIC signal problem and solution
Authors: Lahreche A. , Beggah Y.
Published: March 2011

The question concerning the best electron range to use with uniform generation function to get the best fit of the experimental data is answered by describing a general strategy to extract an effective electron range. This strategy is based on EBIC charge collect efficiency and on EBIC normal collector geometry. The results show that the disagreement between the EBIC signal modelled with the Gaussian generation form with Kyser electron range and that modelled with uniform generation with the extracted electron range is disappeared. The result shows also that the modelled EBIC signal for the case of uniform generation is independent of the shape of generation volume. The fit of the experimental data of charge collection efficiency, stalking fault contrast and grain boundaries contrast using the extracted electron range is illustrated. The use of the extracted electron range can remove some existing disagreement in extraction of the diffusion length value from different existing models (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Regulatory advice and drug development—A case study in negotiating with regulators
Authors: Seldrup Jørgen
Published: March 2011

Regulatory guidance on the development of drugs has existed for well over half a century in some territories. As drug development grew to become global so was born the need for harmonization. Beginning in the 1990s, the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) developed guidelines which were adopted by the Food and Drug Administration (FDA) in the U.S.A., the European Medicines Agency (EMA) in the European Union and the Pharmaceuticals and Medical Devices Agency (PMDA) in Japan. These guidelines are generally not disease specific.

A visit to the web sites of any of the aforementioned Agencies or, for that matter other regulatory agencies outside of these, will witness a plethora of additional/separate guidances, some of which are disease specific. In addition to such written guidances, more specific advice (for example, on a drug development program at the end of Phase II) may be requested from the Regulator.

Despite the harmonization efforts expressed through ICH, the actual advice given by different regulatory authorities in practical situations, however, may be inconsistent.

This paper will describe a case of seeking advice on a Phase III programme from the FDA and the EMA, obtaining different opinions and developing an innovative solution to satisfy both Authorities without necessarily extending development time significantly. The case is chronic kidney disease; the issues concern study design (non‐inferiority, margin, etc.); the solution required a non‐traditional design and associated sample size considerations.

We conclude with some general advice on ‘talking to the regulator’.

This work was originally presented as a Poster at the Statistical Methods in Biopharmacy, 6th International Meeting, Paris, 21–22 September 2009. Copyright © 2011 John Wiley & Sons, Ltd.
Bayesian hybrid dose‐finding design in phase I oncology clinical trials
Authors: Yuan Ying , Yin Guosheng
Published: March 2011

In oncology, dose escalation is often carried out to search for the maximum tolerated dose (MTD) in phase I clinical trials. We propose a Bayesian hybrid dose‐finding method that inherits the robustness of model‐free methods and the efficiency of model‐based methods. In the Bayesian hypothesis testing framework, we compute the Bayes factor and adaptively assign a dose to each cohort of patients based on the adequacy of the dose–toxicity information that has been collected thus far. If the data observed at the current treatment dose are adequately informative about the toxicity probability of this dose (e.g. whether this dose is below or above the MTD), we make the decision of dose assignment (e.g. either to escalate or to de‐escalate the dose) directly without assuming a parametric dose–toxicity curve. If the observed data at the current dose are not sufficient to deliver such a definitive decision, we resort to a parametric dose–toxicity curve, such as that of the continual reassessment method (CRM), in order to borrow strength across all the doses under study to guide dose assignment. We examine the properties of the hybrid design through extensive simulation studies, and also compare the new method with the CRM and the ‘3 + 3’ design. The simulation results show that our design is more robust than parametric model‐based methods and more efficient than nonparametric model‐free methods. Copyright © 2011 John Wiley & Sons, Ltd.
Wnt Signaling Promotes Neuronal Differentiation from Mesenchymal Stem Cells Through Activation of Tlx3
Authors: Kondo Takako , Matsuoka Akihiro J. , Shimomura Atsushi , Koehler Karl R. , Chan Rebecca J. , Miller Josef M. , Srour Edward F. , Hashino Eri
Published: March 2011

Wnt/β-catenin signaling promotes neural differentiation by activation of the neuron-specific transcription factors, Neurogenin1 (Ngn1), NeuroD, and Brn3a, in the nervous system. As neurons in cranial sensory ganglia and dorsal root ganglia transiently express Ngn1, NeuroD, and Brn3a during embryonic development, we hypothesized that Wnt proteins could instructively promote a sensory neuronal fate from mesenchymal stem cells (MSCs) directed to differentiate into neurons. Consistent with our hypothesis, Wnt1 induced expression of sensory neuron markers including Ngn1, NeuroD, and Brn3a, as well as glutamatergic markers in neurally induced MSCs in vitro and promoted engraftment of transplanted MSCs in the inner ear bearing selective loss of sensory neurons in vivo. Given the consensus function of T-cell leukemia 3 (Tlx3), as a glutamatergic selector gene, we postulated that the effects of canonical Wnt signaling on sensory neuron and glutamatergic marker gene expression in MSCs may be mediated by Tlx3. We first confirmed that Wnt1 indeed upregulates Tlx3 expression, which can be suppressed by canonical Wnt inhibitors. Next, our chromatin immunoprecipitation assays revealed that T-cell factor 3/4, Wnt-activated DNA binding proteins, interact with a regulatory region of Tlx3 in MSCs after neural induction. Furthermore, we demonstrated that forced expression of Tlx3 in MSCs induced sensory and glutamatergic neuron markers after neural induction. Together, these results identify Tlx3 as a novel target for canonical Wnt signaling that confers somatic stem cells with a sensory neuron phenotype upon neural induction.
Female external genitalia on fetal magnetic resonance imaging
Authors: Nemec S. F. , Nemec U. , Weber M. , Rotmensch S. , Brugger P. C. , Kasprian G. , Krestan C. R. , Rimoin D. L. , Graham J. M. , Prayer D.
Published: March 2011

Objectives

To characterize the normal development of the female external genitalia on fetal magnetic resonance imaging (MRI).

Methods

This retrospective study included MRI examinations of 191 female fetuses (20–36 gestational weeks) with normal anatomy or minor abnormalities, following suspicion of anomalies on prenatal ultrasound examination. Using a 1.5‐Tesla unit, the bilabial diameter was measured on T2‐weighted sequences. Statistical description, as well as correlation and regression analyses, was used to evaluate bilabial diameter in relation to gestational age. MRI measurements were compared with published ultrasound data. The morphological appearance and signal intensities of the external genitalia were also assessed.

Results

Mean bilabial diameters, with 95% CIs and percentiles, were defined. The bilabial diameter as a function of gestational age was expressed by the regression equation: bilabial diameter = − 11.336 + 0.836 × (gestational age in weeks). The correlation coefficient, r = 0.782, was statistically significant (P < 0.001). Bilabial diameter on MRI was not significantly different from that on ultrasound (P < 0.001). In addition, on MRI we observed changes in morphology of the external genitalia and in signal intensities with increasing gestational age.

Conclusions

We have provided a reference range of fetal bilabial diameter on MRI, which, in addition to ultrasound findings, may be helpful in the identification of genital anomalies. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Changes in myocardial performance index and aortic isthmus and ductus venosus Doppler in term, small‐for‐gestational age fetuses with normal umbilical artery pulsatility index
Authors: Cruz‐Martinez R. , Figueras F. , Hernandez‐Andrade E. , Oros D. , Gratacos E.
Published: March 2011

Objective

To evaluate the changes in myocardial performance index (MPI) and aortic isthmus (AoI) and ductus venosus (DV) Doppler in term, small‐for‐gestational age (SGA) fetuses with normal umbilical artery (UA) Doppler.

Methods

MPI, AoI and DV pulsatility indices (PI) were measured within 1 week prior to delivery in a cohort of 178 term singleton consecutive SGA fetuses with normal UA‐PI (< 95th percentile) and 178 controls matched by gestational age. Cardiovascular parameters were converted into Z‐scores and values above the 95th centile defined as abnormal.

Results

Median gestational age at inclusion and at delivery was 35.7 and 38.6 weeks, respectively. Compared to controls, SGA fetuses showed significantly higher values in MPI and AoI‐PI and similar values in DV‐PI. SGA fetuses showed a significantly higher proportion of increased MPI (28.1 vs. 6.7%; P < 0.01) and abnormal AoI‐PI (14.6 vs. 5.1%; P < 0.01) than controls. The proportion of cases with abnormal DV‐PI was similar between SGA cases and controls. Retrograde net blood flow in the AoI was observed in 7.3% of the SGA cases and in none of the controls.

Conclusion

A proportion of SGA fetuses show cardiovascular Doppler abnormalities. This information might be of clinical relevance in improving the detection and management of late‐onset intrauterine growth restriction. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Prenatally detectable congenital heart defects in fetuses with Down syndrome
Authors: Mogra R. , Zidere V. , Allan L. D.
Published: March 2011

Objective

To document the incidence of congenital heart defects (CHD) that are detectable echocardiographically in the fetus with trisomy 21 and the relationship with nuchal translucency, fetal sex and ethnicity.

Methods

Data on fetuses with a karyotypic diagnosis of trisomy 21 were collected between January 2002 and March 2010. The data were analyzed for the gestational age at examination, maternal age, reason for referral for fetal echocardiography, cardiac diagnosis, fetal sex, ethnicity and outcome.

Results

Of 917 fetuses with trisomy 21, 487 had a diagnostic echocardiogram. Cardiac examination was performed before 14 weeks' gestation in 75% of cases. The main reasons for referral were increased nuchal translucency (NT) in 76% of cases, suspected cardiac abnormality in 15% and an extracardiac anomaly in 6%. Structural CHD was found in 164/487 (34%), or 98/412 (24%) if those referred for suspected CHD are removed from the analysis. The most common diagnosis was atrioventricular septal defect (AVSD) (115/487, 24%). The ratio of female to male fetuses with AVSD was 29%:18% (P = 0.003). There was no difference in the incidence of AVSD with ethnicity. The pregnancy continued in 36 cases, but three were lost to follow‐up; of the known outcomes there were 10 intrauterine deaths, six of which had structural heart disease, and 23 live births, 15 of which had CHD.

Conclusion

Most fetuses (66–76%) with trisomy 21 have a structurally normal heart on echocardiography. The presence of structural CHD was not associated with increased NT. The increased incidence of AVSD in females was confirmed in our study, although an ethnic difference could not be confirmed. CHD does not appear to increase the chance of spontaneous intrauterine loss in ongoing pregnancies. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Learning through gesture
Authors: Goldin‐Meadow Susan
Published: March 2011

When people talk, they move their hands—they gesture. Although these movements might appear to be meaningless hand waving, in fact they convey substantive information that is not always found in the accompanying speech. As a result, gesture can provide insight into thoughts that speakers have but do not know they have. Even more striking, gesture can mark a speaker as being in transition with respect to a task—learners who are on the verge of making progress on a task routinely produce gestures that convey information that is different from the information conveyed in speech. Gesture can thus be used to predict who will learn. In addition, evidence is mounting that gesture not only presages learning but also can play a role in bringing that learning about. Gesture can cause learning indirectly by influencing the learning environment or directly by influencing learners themselves. We can thus change our minds by moving our hands. WIREs Cogni Sci 2011 2 595–607 DOI: 10.1002/wcs.132

This article is categorized under:

Psychology > Learning
A novel fission yeast mei4 mutant that allows efficient synchronization of telomere dispersal and the first meiotic division
Authors: Kakui Yasutaka , Sato Masamitsu , Tanaka Kayoko , Yamamoto Masayuki
Published: March 2011

The progression of meiosis is controlled by a number of gene‐expression systems in the fission yeast Schizosaccharomyces pombe. A forkhead‐type transcription factor Mei4 activates a number of genes essential for progression from the middle to late stages of meiosis, which include meiosis I, meiosis II and sporulation. The mei4‐deletion mutant (mei4Δ) arrests after meiotic prophase and does not enter meiosis I. To further analyse the Mei4 function, we isolated novel temperature‐sensitive mei4 alleles. The two alleles isolated in the initial screen turned out to contain a substitution at N136 in the forkhead DNA‐binding domain. Among site‐directed mutants that carried a point mutation at this position, the mei4‐N136A mutant showed the most severe temperature sensitivity. The mei4‐N136A mutant arrested before meiosis I at the restrictive temperature, as did the mei4Δ mutant. In fission yeast, the telomeres are clustered at the spindle pole body (SPB) in meiotic prophase and disperse from it at the onset of meiosis I. The mei4Δ mutant was found to arrest with its telomeres clustered at the SPB, demonstrating a role for Mei4 in telomere dispersion. The mei4‐N136A mutant also arrested with clustered telomeres at the restrictive temperature, and the clustering was synchronously resolved after a temperature down‐shift, indicating that mei4‐N136A is a reversible allele. Hence, the mei4‐N136A mutant will be a unique tool to synchronize the meiotic cell cycle from meiosis I onwards and may facilitate analyses of cellular activities occurring during meiosis I. Copyright © 2011 John Wiley & Sons, Ltd.
Schizosaccharomyces pombe Arc3 is a conserved subunit of the Arp2/3 complex required for polarity, actin organization, and endocytosis
Authors: Cabrera Rodrigo , Suo Jinfeng , Young Evelin , Chang Eric C.
Published: March 2011

We characterized the Schizosaccharomyces pombe arc3 gene, whose product shares sequence homology with that of the budding yeast ARC18 and human ARPC3/p21 subunits of the Arp2/3 complex. Our data showed that Arc3p co‐localizes with F‐actin patches at the cell ends, but not with F‐actin cables or the equatorial actin ring, and binds other subunits of the Arp2/3 complex. Gene deletion analysis showed that arc3 is essential for viability. When arc3 expression was repressed, F‐actin patches became dispersed throughout the cell with greatly reduced mobility. Furthermore, in arc3‐repressed cells, endocytosis was also inhibited. Human ARPC3 rescued the viability of the Sz. pombe arc3 null mutant; in addition, ARPC3 also localized to F‐actin patches in human cells. These data suggest that Arc3p is an evolutionarily conserved subunit of the Arp2/3 complex required for proper F‐actin organization and efficient endocytosis. Copyright © 2011 John Wiley & Sons, Ltd.
The current potential of high‐intensity focused ultrasound for pancreatic carcinoma
Authors: Sofuni Atsushi , Moriyasu Fuminori , Sano Takatomo , Yamada Kota , Itokawa Fumihide , Tsuchiya Takayoshi , Tsuji Shujiro , Kurihara Toshio , Ishii Kentaro , Itoi Takao
Published: March 2011

Introduction

Pancreatic carcinoma has one of the poorest prognoses among malignant tumors. Many pancreatic carcinoma patients who undergo common treatments, such as surgery, radio‐chemotherapy and chemotherapy, gained little benefit because of the histological characteristics.

Materials and methods

HIFU is a new technique of noninvasive treatment for unresectable pancreatic carcinoma. HIFU has the ability to ablate the deep tissues inside body from an external source using high‐intensity focused ultrasound. The effects of HIFU can result in cell destruction and tissue necrosis.

Results

Results from study in China in 251 patients with advanced pancreatic carcinoma suggested that HIFU treatment could reduce the size of tumors without causing complications and prolong survival. Moreover, according to some reports from China, HIFU treatment is suggested to be useful as the one of palliative treatments for unresectable pancreatic carcinoma. Our case of HIFU therapy for pancreatic carcinoma is presented including pathological findings in this paper. The results suggested that HIFU treatment might be effective in controlling local tumor.

Conclusion

HIFU therapy may have the possibility of becoming one of the combination therapies for treating pancreatic carcinoma in the future.
Applications of self‐organizing map for patterning macrofungal diversity of xerothermic swards
Authors: Adamczyk Jolanta J.
Published: March 2011

Macrofungal communities were investigated in four associations of xerothermic swards: Festucetum pallentis, Origano‐Brachypodietum, Adonido‐Brachypodietum pinnati and Diantho‐Armerietum elongatae in a Jurassic area of the Częstochowa Upland (southern Poland). A total of 47 species were recorded. The self‐organising map (SOM)—an unsupervised algorithm for artificial neural networks—was used to recognise patterns in the macrofungal communities of diverse xerothermic swards. Only two associations were mycologically similar: Origano‐Brachypodietum and Adonido‐Brachypodietum pinnati. Species with high and significant IndVal (the species indicator value) for each investigated phytocoenoses are presented. The presence of macrofungal species and the participation of indicator species were connected with habitat factors of plant associations, as documented by the IndVal application. In the least fertile phytocoenoses, macrofungal communities were poor with few indicator species. The more fertile phytocoenoses had richer and more varied communities of macrofungi with higher numbers of indicator species. The ordering methods applied in this study were very effective for analyzing the macrofungal communities existing in plant associations.
A systematic review of named entity recognition in biomedical texts
Authors: Goulart Rodrigo Rafael Villarreal , Strube de Lima Vera Lúcia , Xavier Clarissa Castellã
Published: March 2011

Biomedical Named Entities (NEs) are phrases or combinations of phrases that denote specific objects or groups of objects in the biomedical literature. Research on Named Entity Recognition (NER) is one of the most disseminated activities in the automatic processing of biomedical scientific articles. We analyzed articles relevant to NER in biomedical texts, in the period from 2007 to 2009, through a systematic review. The results identify the main methods in the recognition of Biomedical NEs, features and methodologies for a NER system implementation. Aside from the tendencies identified, some gaps are detected that may constitute opportunities for new studies in the area.
BLAMING THE GODS: CHRISTIAN RELIGIOUS PROPAGANDA IN THE NIGERIA–BIAFRA WAR
Authors: OMENKA NICHOLAS IBEAWUCHI
Published: March 2011

The consensus among many analysts of the Nigeria–Biafra War is that the conflict cannot be reduced to a mono-causal explanation. The tragedy that befell the West African country from 1966 to 1970 was a combination of many factors, which were political, ethnic, religious, social, and economic in nature. Yet the conflict was unduly cast as a religious war between Christians and Muslims. Utilizing newly available archival materials from within and outside Nigeria, this article endeavours to unravel the underlying forces in the religious war rhetoric of the mainly Christian breakaway region and its Western sympathizers. Among other things, it demonstrates that, while the religious war proposition was good for the relief efforts of the international humanitarian organizations, it inevitably alienated the Nigerian Christians and made them unsympathetic to the Biafran cause.
CHRONICLE OF A COUP FORETOLD: VALENTINE MUSAKANYA AND THE 1980 COUP ATTEMPT IN ZAMBIA
Authors: LARMER MILES
Published: March 2011

Zambia's unsuccessful coup attempt in 1980 was initiated by members of the country's intellectual and business elite, who had played a leading role in the postcolonial civil service and state bureaucracy, but who became disillusioned with the takeover of the state by the ruling party before and after the declaration of the one-party state in 1972. Among their number was Valentine Musakanya, one of those convicted for the coup attempt. Using Musakanya's biographical and other writings, this article explores his intellectual trajectory from head of the civil service to political prisoner. In so doing, it investigates the role of life writing in aiding understanding of the postcolonial political history of Africa.
Immunization with crude antigens plus aluminium hydroxide protects cattle fromFasciola hepaticainfection
Authors: Guasconi L. , Serradell M.C. , Borgonovo J. , Garro A.P. , Varengo H. , Caffe G. , Masih D.T.
Published: March 2011

The ability of total homogenate (TH) ofFasciola hepaticaconjugated with aluminium hydroxide (alum) or Freund's complete adjuvant (FCA) to protect cattle against experimental fasciolosis was evaluated. Compared with the infected group, the immunized animals with alum-TH and FCA-TH presented a significant reduction in fluke burden (85.9% and 96.8%, respectively), a higher percentage of short-sized worms, a marked reduction in the released eggs in faeces (89% and 57%, respectively), as well as an increased production of specific antibodies before infection. The alum-TH immunized group also showed a significant increase in the antigen-specific proliferation of peripheral blood mononuclear cells (PBMC) as early as 4 weeks before infection. Although both immunized groups (alum-TH and FCA-TH) were able to develop an efficient protective immune response to metacercarial challenge, an earlier PBMC response, lower hepatic damage and less effect on weight gain were found in alum-immunized animals. Therefore, alum is a good candidate for future immunization against bovine fasciolosis.
Taxonomic revision of BrazilianTethya(Porifera: Hadromerida) with description of four new species
Authors: Ribeiro Suzi M. , Muricy Guilherme
Published: March 2011

The taxonomy of the genusTethyafrom Brazil is revised. Five species are described, four of which are new to science:Tethya maza, T. beatrizaesp. nov.,T. nicoleaesp. nov.,T. parvulasp. nov., andT. solangeaesp. nov. Five earlier records ofTethyafrom Brazil(T. aurantium, T. diploderma, T. maza, T. japonicaandT. seychellensis)are re-evaluated and onlyT. mazais confirmed. The other previous records ofTethyafrom Brazil, viz.,Tethya brasiliana, T. cyanae, T. ignisandT. rubra,have been recently described in detail using scanning electron microscopy and are also considered valid. An amendment to the nomenclature of micrasters is made, recognizing at least two different morphologies of each type of micraster (strongylasters types 1 and 2, tylasters types 1 and 2, and oxyasters types 1, 2 and 3). A neotype was designated forT. maza. With four new species described here and four previous records considered invalid the known diversity ofTethyain Brazil still remains nine species. However, its rate of endemism has increased from 44% to 89%.
Surprise, surprise
Authors: Dennett Daniel C.
Published: March 2011

The authors show that some long-standing confusions and problems can be avoided by thinking of perception in terms of sensorimotor contingencies, a close kin to my heterophenomenological approach (Dennett 1991). However, their claim that subjects do not have any commitments about the resolution of their visual fields is belied by the surprise routinely expressed by subjects when this is demonstrated to them.
HIGHER-ORDER ACCURATE, POSITIVE SEMIDEFINITE ESTIMATION OF LARGE-SAMPLE COVARIANCE AND SPECTRAL DENSITY MATRICES
Authors: Politis Dimitris N.
Published: March 2011

A new class of large-sample covariance and spectral density matrix estimators is proposed based on the notion of flat-top kernels. The new estimators are shown to be higher-order accurate when higher-order accuracy is possible. A discussion on kernel choice is presented as well as a supporting finite-sample simulation. The problem of spectral estimation under a potential lack of finite fourth moments is also addressed. The higher-order accuracy of flat-top kernel estimators typically comes at the sacrifice of the positive semidefinite property. Nevertheless, we show how a flat-top estimator can be modified to become positive semidefinite (even strictly positive definite) while maintaining its higher-order accuracy. In addition, an easy (and consistent) procedure for optimal bandwidth choice is given; this procedure estimates the optimal bandwidth associated with each individual element of the target matrix, automatically sensing (and adapting to) the underlying correlation structure.
Can Low-Cost Road Vehicles Positioning Systems Fulfil Accuracy Specifications of New ADAS Applications?
Authors: Jiménez F. , Naranjo J. E. , García F. , Armingol J. M.
Published: March 2011

Some new Advanced Driver Assistance Systems (ADAS) need on-the-lane vehicle positioning on accurate digital maps, but current applications of vehicle positioning do not justify the surcharge of very accurate equipment such as DGPS or high-cost inertial systems. For this reason, the performance of GPS in autonomous mode is analyzed. Although satisfactory results can be found, in some areas the GPS signal is lost or degraded so it is necessary to know the positioning error when using only inertial system data. A theoretical approach based on the uncertainty propagation law is used to estimate the upper limit of distance that can be travelled fulfilling the specifications of an assistance system. Test results support the conclusions of this approach. Finally, the combination of GPS and inertial systems is studied, with the conclusion that the theoretical approach is valid when inertial measurements are used right from the start of GPS signal degradation, without waiting for a complete loss of signal.
Quittant tout, nous partîmes: quitteretpartirà la lumière des changements de relation locative
Authors: AURNAGUE MICHEL
Published: March 2011

Ce travail propose une comparaison des emplois spatiaux dequitteretpartirs'appuyant sur l'exploitation d'exemples de la base Frantext entre 1880 et 1970. Après avoir exposé les principales oppositions quantitatives et qualitatives émergeant de ce recensement, nous proposons une analyse departirqui tente de déterminer la/les relation(s) locative(s) élémentaire(s) sous-tendant son contenu sémantique. Cette analyse sert de point de départ à l'étude dequitter, verbe dont l'examen montre qu'il peut asserter puis nier un éventail beaucoup plus large de relations spatiales. L'article se termine par une discussion faisant apparaître que la nature des sites (entités de référence ou localisatrices) auxquels font appel les deux verbes est largement conditionnée par les relations locatives présentes dans leur sémantisme et que seulpartirdénote des déplacements au sens strict.
A cost comparison of more and less nutritious food choices in US supermarkets
Authors: Katz David L , Doughty Kim , Njike Valentine , Treu Judith A , Reynolds Jesse , Walker Jennifer , Smith Erica , Katz Catherine
Published: March 2011

Objective

The present study directly compared prices of more and less nutritious foods within given categories in US supermarkets.

Design

Foods selected from six supermarkets in Jackson County were categorized using the five criteria of the Nutrition Detectives™ (ND) programme and an item-to-item cost comparison was made using posted prices. The nutritional quality of foods was distinguished using the clues of the ND nutrition education programme for elementary-school children and validated using the Overall Nutritional Quality Index.

Setting

Supermarkets in Jackson County, MO, USA.

Subjects

Not applicable.

Results

The average price of the item for more nutritious foods did not differ significantly from that of less nutritious foods overall ($US 2·89 (sd$US 0·74)v.$US 2·85 (sd$0·68),P= 0·76). More nutritious breads cost more than less nutritious breads ($US 3·36 (sd$ US 0·28)v.$US 2·56 (sd$US 0·80,P= 0·03), whereas more nutritious cereals ($US 2·46 (sd$US 0·69)v.$US 3·50 (sd$US 0·30),P< 0·01) and cookies ($US 2·76 (sd$US 0·50)v.$US 3·40 (sd$US0·28),P< 0·01) cost less.

Conclusions

Our findings indicate that it is possible to choose more nutritious foods within many common categories without spending more money and suggest that making small improvements in dietary choices does not invariably cost more.
Family meals and body weight in US adults
Authors: Sobal Jeffery , Hanson Karla
Published: March 2011

Objective

Family meals are an important ritual in contemporary societies and many studies have reported associations of family meals with several biopsychosocial outcomes among children and adolescents. However, few representative analyses of family meals have been conducted in samples of adults, and adults may differ from young people in predictors and outcomes of family meal consumption. We examined the prevalence and predictors of adult family meals and body weight outcomes.

Design

The cross-sectional 2009 Cornell National Social Survey (CNSS) included questions about the frequency of family meals, body weight as BMI and sociodemographic characteristics.

Setting

The CNSS telephone survey used random digit dialling to sample individuals.

Subjects

We analysed data from 882 adults living with family members in a nationally representative US sample.

Results

Prevalence of family meals among these adults revealed that 53 % reported eating family meals seven or more times per week. Predictive results revealed that adults who more frequently ate family meals were more likely to be married and less likely to be employed full-time, year-round. Outcome results revealed that the overall frequency of family meals among adults was not significantly associated with any measure of body weight. However, interaction term analysis suggested an inverse association between frequency of family meals and BMI for adults with children in the household, and no association among adults without children.

Conclusions

These findings suggest that family meals among adults are commonplace, associated with marital and work roles, and marginally associated with body weight only in households with children.
Antibody-Mediated Self-Limiting Self-Assembly for Quantitative Analysis of Nanoparticle Surfaces by Atomic Force Microscopy
Authors: Geronimo Carly Lay A. , MacCuspie Robert I.
Published: March 2011

Quantification of very low density molecular coatings on large (60 nm) gold nanoparticles (AuNPs) is demonstrated via the use of antibody-mediated self-limiting self-assembly of small and large AuNPs into raspberry-like structures subsequently imaged by atomic force microscopy (AFM). AFM imaging is proposed as an automated, lower-cost, higher-throughput alternative to immunostaining and imaging by transmission electron microscopy. Synthesis of large AuNPs, containing one of three ligand molecules in one of three stoichiometries (1, 2, or 10 ligands per AuNP), and small probe AuNPs with one of three antibody molecules in a one antibody per AuNP ratio, enabled a range of predicted self-limiting self-assembled structures. A model predicting the probability of observing a given small to large AuNP ratio based on a topography measurement such as AFM is described, in which random orientational deposition is assumed and which accounts for the stochastic synthesis method of the library AuNPs with varied ligand ratios. Experimental data were found to agree very well with the predictive models when using an established AFM sample preparation method that avoids drying-induced aggregation.
Characterizing Materials for Energy Generation Using X-ray Photoelectron Spectroscopy (XPS)
Authors: Nunney Tim , White Richard
Published: March 2011

In order to meet the challenges of more economical and environmentally benign energy production, a new generation of complex materials and devices are being developed, including thin film solar cells, fuel cells, and batteries. In all stages of development there is a requirement for materials characterization and analysis, from the initial development stages through to testing of the finished product. Most materials need to be analyzed for compositional homogeneity across surfaces and also for confirmation of film thickness and layer chemistry.
Pioneers in Optics: Leonhard Euler and Étienne-Louis Malus
Authors: Davidson Michael W.
Published: March 2011

Leonhard Euler is best known as a prolific mathematician, but he also made notable contributions in optics and astronomy. He was born in Basel, Switzerland on April 15, 1707, the son of Paul Euler, a Protestant minister, and Margaret Brucker, the daughter of a Protestant minister. Accordingly, Leonhard Euler was raised to follow suit and join the ministry, but his father had sparked his interest in mathematics at a young age, and this interest was further cultivated at the University of Basel, which he entered at the age of fourteen. His prodigious ability in the field impressed renowned mathematics professor Johann Bernoulli, who allowed Euler to visit with him on Sundays to discuss any difficulties the young scholar had in understanding the advanced books on mathematics that he had recommended. Nevertheless, even in 1723, Euler still appeared to be set on a course that would lead him to the church, having gained his Master's degree in philosophy and embarked on studies of theology. Soon after, however, with the help of Bernoulli, Euler convinced his father to permit him to study mathematics instead.
All the Better to See You With
Authors: Carmichael Stephen W.
Published: March 2011

In the animal kingdom, eyes come in a relatively small variety of functional forms. When a new optical system is found, it usually is a variation of a known form. It is very rare to discover a novel form of an eye. Such a sensational discovery has been made by Annette Stowasser, Alexandra Rapaport, John Layne, Randy Morgan, and Elke Buschbeck. Using two different experimental approaches, they demonstrated an eye with a truly bifocal lens, something that has only been suggested for certain long-extinct trilobites
Bugscope: Online K–12 Microscopy Outreach
Authors: Robinson Scott , Conway Chas , Wallace Cate , Ray Ann M. , Thakkar Umesh
Published: March 2011

Bugscope is a free online microscopy outreach program that offers K–12 classrooms anywhere in the world the ability to remotely operate a high-resolution scanning electron microscope, collect images of insects and other similar arthropods, and chat simultaneously with a team of scientists. It was conceived and implemented in the late 1990s when K–12 schools were beginning to gain broadband Internet access, many as a result of the Telecommunications Act of 1996. One of several projects that took advantage of this opportunity to use the Internet to bring the laboratory into the classroom, Bugscope began as an NSF grant to purchase a field-emission scanning electron microscope and develop sophisticated client and server software to control it via a standard web browser. Inspired by the success of and lessons learned from the Chickscope remote magnetic resonance imaging project and from having successfully established remote web-based control of a transmission electron microscope, Clint Potter and Bridget Carragher created the Bugscope project with the goal of developing a remote microscopy educational outreach project that would be sustainable over the long term. This goal led to two significant design decisions. First, the software involved in setting up and running the live outreach sessions was purpose-built to ensure that only one staff member, if necessary, would be required at the instrument (as opposed to Chickscope, which required staff at the remote location as well as at the instrument). Second, students from a local high school would be employed as a renewable resource to help with pre-session sample preparation and to participate in live chat, answering questions from the remote classrooms. Although we now operate with permanent staff at the instrument, these efficiencies in the original concept/design have allowed Bugscope to operate continuously since March 1999, long after the original funding was exhausted.
Hardware efficient receiver for low-cost ultra-high rate 60 GHz wireless communications
Authors: Ulusoy Ahmet Çağrı , Liu Gang , Trasser Andreas , Schumacher Hermann
Published: March 2011

This paper presents a hardware efficient receiver architecture, to be used in low-cost, ultra-high rate 60 GHz wireless communication systems. The receiver utilizes a simple, feed-forward carrier recovery concept, performing phase and frequency synchronization in the analog domain. This enables 1-bit baseband processing without a need of ultra-high speed and high precision analog-to-digital conversion, offering a strong simplification of the system architecture and comparatively low power consumption. In a first prototype implementation, the receiver is realized in a low-cost SiGe technology as two separate ICs: the 60 GHz/5 GHz downconverter, and the intermediate frequency synchronous demodulator. The simple synchronous reception concept is experimentally validated for up to 3.5 Gbit/s data rate, which constituted the limit of the existing experimental setup. Furthermore, the downconverter demonstrates that low-cost technologies (fop/fmax ~ 0.75) can be used to realize short-range data links at 60 GHz, with low-noise amplifiers in a more performant technology as needed.
Resolution of infection promotes a state of dormancy and long survival of CD4 memory T cells
Authors: Dalai Sarat K , Khoruzhenko Stanislav , Drake Charles G , Jie Chunfa C , Sadegh‐Nasseri Scheherazade
Published: March 2011

Memory T cells survive throughout the lifetime of an individual and are protective upon recall. It is not clear how memory T cells can live so long. Here, we demonstrate that at the resolution of a viral infection, low levels of antigen are captured by B cells and presented to specific CD4+ memory T cells to render a state of unresponsiveness. We demonstrate in two systems that this process occurs naturally during the fall of antigen and is associated with a global gene expression program initiated with the clearance of antigen. Our study suggests that in the absence of antigen, a state of dormancy associated with low‐energy utilization and proliferation can help memory CD4+ T cells to survive nearly throughout the lifetime of mice. The dormant CD4+ memory T cells become activated by stimulatory signals generated by a subsequent infection. We propose that quiescence might be a mechanism necessary to regulate long‐term survival of CD4 memory T cells and to prevent cross‐reactivity to self, hence autoimmunity.
Stochastic and deterministic processes interact in the assembly of desert microbial communities on a global scale
Authors: Caruso Tancredi , Chan Yuki , Lacap Donnabella C , Lau Maggie C Y , McKay Christopher P , Pointing Stephen B
Published: March 2011

Extreme arid regions in the worlds' major deserts are typified by quartz pavement terrain. Cryptic hypolithic communities colonize the ventral surface of quartz rocks and this habitat is characterized by a relative lack of environmental and trophic complexity. Combined with readily identifiable major environmental stressors this provides a tractable model system for determining the relative role of stochastic and deterministic drivers in community assembly. Through analyzing an original, worldwide data set of 16S rRNA-gene defined bacterial communities from the most extreme deserts on the Earth, we show that functional assemblages within the communities were subject to different assembly influences. Null models applied to the photosynthetic assemblage revealed that stochastic processes exerted most effect on the assemblage, although the level of community dissimilarity varied between continents in a manner not always consistent with neutral models. The heterotrophic assemblages displayed signatures of niche processes across four continents, whereas in other cases they conformed to neutral predictions. Importantly, for continents where neutrality was either rejected or accepted, assembly drivers differed between the two functional groups. This study demonstrates that multi-trophic microbial systems may not be fully described by a single set of niche or neutral assembly rules and that stochasticity is likely a major determinant of such systems, with significant variation in the influence of these determinants on a global scale.
New thioxanthone and xanthone photoinitiators based on silyl radical chemistry
Authors: Lalevée Jacques , Blanchard Nicolas , Tehfe Mohamad Ali , Fries Cédric , Morlet-Savary Fabrice , Gigmes Didier , Fouassier Jean Pierre
Published: March 2011

New cleavable photoinitiators are presented. As demonstrated here, combining the thioxanthone/xanthone (or other PI skeletons) and silyl chemistries should open up a new promising direction of research.
Business: At the Table or on the Table: It's Our Choice
Authors: Henri Bernard P.
Published: March 2011

Today the need for advocacy on behalf of audiology and speech-language pathology services is greater than ever. Demand continues to grow, while resources continue to shrink. We can choose to be at the negotiating table to ensure that the interests of our profession and our clients are addressed, or we can be “on the table” watching as resources are distributed without our input.
Business: Conceptualizations of Organizational Change Viewed Through the Lens of Power: A Tutorial for the Speech-Language Pathologist/Audiologist Administrator
Authors: Walden Patrick R.
Published: March 2011

Both educational and health care organizations are in a constant state of change, whether triggered by national, regional, local, or organization-level policy. The speech-language pathologist/audiologist-administrator who aids in the planning and implementation of these changes, however, may not be familiar with the expansive literature on change in organizations. Further, how organizational change is planned and implemented is likely affected by leaders' and administrators' personal conceptualizations of social power, which may affect how front line clinicians experience organizational change processes. The purpose of this article, therefore, is to introduce the speech-language pathologist/audiologist-administrator to a research-based classification system for theories of change and to review the concept of power in social systems. Two prominent approaches to change in organizations are reviewed and then discussed as they relate to one another as well as to social conceptualizations of power.
Converging Communication Vulnerabilities in Health Care: An Emerging Role for Speech-Language Pathologists and Audiologists
Authors: Blackstone Sarah W. , Ruschke Karin , Wilson-Stronks Amy , Lee Charles
Published: March 2011

The needs to improve health care outcomes and reduce health care costs in the United States are important national health policy goals. Research suggests that improving patient-provider communication is a critical step toward those goals. Speech-language pathologists (SLPs) and audiologists are uniquely educated and clinically prepared to lead in this effort. This article advocates for becoming involved in implementing new standards and regulations that address the need for “effective communication, cultural competence and patient- and family-centered care.” Using three case examples, the article highlights the convergence of communication challenges faced by 4 groups with communication vulnerabilities: those with speech, language, hearing, vision and cognitive impairments; limited English proficiency; little knowledge about healthcare (poor health literacy); and/or cultural, sexual identity, or religious differences. Authors discuss the need for SLPs and audiologists to advocate for the use of key assistive technologies and strategies that help individuals who are communication-vulnerable interact more effectively with their health care providers. They also call for active and systematic collaborations among professions representing groups currently at high risk for health disparities. As Henry Ford said, “Coming together is a beginning. Keeping together is progress. Working together is success.”