bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the bond polarizabilities of zincblende‐type semiconductors: Application to the Raman spectra of disordered GaSb/AlSb (001) superlattices
Authors: Berdekas D. , Ves S.
Published: May 2012

We derive expressions for the bond polarizability (BP) parameters involving only directly measurable quantities, such as dielectric and elasto‐optic constants of the bulk crystal and apply them to zincblende‐type crystals. The vibrational modes are calculated on the basis of an eleven (11) parameter rigid‐ion model approximation (RIM). Having estimated the BP parameters for GaSb and AlSb bulk crystals, we calculate the Raman spectra away of resonance conditions for the vibrations of perfect and disordered (GaSb)1/(AlSb)1 (001) superlattices (SL). The disordered SL is approximated with primitive cells much larger than the primitive cell of the perfect 1 × 1 SL. Furthermore, we show that disorder modifies the Raman spectra of the perfect SL by introducing asymmetry as well as by the formation of additional peaks in both the acoustic and optical range of the Raman spectra. Puzzlingly, even a small degree of disorder, results in a blueshift of all modes frequencies, especially the strongest optical ones.
Modeling molecular interactions by analytic potentials: Analytic perturbation treatment
Authors: Kryachko Eugene S.
Published: May 2012

One of the chief concepts of molecular interactions is the concept of the molecular potential. This work focuses on the class of so‐called spiked potentials. It is analytically demonstrated that despite the common belief that the traditional perturbation theory is not applicable to study the class of potentials combining the harmonic oscillator with a singular potential of the type λr−α, this work aims to propose and develop such treatment on the basis of the appropriate choice of the zero‐order exactly solvable Hamiltonian Ho = −(
$\hbar^2$/(2m))∇ + U2 where U2(r) = αr2 + β/r−2. © 2012 Wiley Periodicals, Inc.
Multicomponent mixed dopant optimization for rapid screening of polycyclic aromatic hydrocarbons using ultra high performance liquid chromatography coupled to atmospheric pressure photoionization high‐resolution mass spectrometry
Authors: Amad Salim Sioud, Ma'an , Al‐Talla Zeyad A.
Published: May 2012

RATIONALE

To enhance the ionization efficiencies in atmospheric pressure photoionization mass spectrometry a dopant with favorable ionization energy such as chlorobenzene is typically used. These dopants are typically toxic and difficult to mix with water‐soluble organic solvents. In order to achieve a more efficient and less toxic dopant, a multicomponent mixed dopant was explored.

METHODS

A multicomponent mixed dopant for non‐targeted rapid screening of polycyclic aromatic hydrocarbons (PAHs) was developed and optimized using ultra high performance liquid chromatography (UPLC) coupled to atmospheric pressure photoionization high‐resolution mass spectrometry. Various single and multicomponent mixed dopants consisting of ethanol, chlorobenzene, bromobenzene, anisole and toluene were evaluated.

RESULTS

Fourteen out of eighteen PAHs were successfully separated and detected at low pg/μL levels within 5 min with high mass accuracy ≤4 ppm. The optimal mixed multicomponent dopant consisted of ethanol/chlorobenzene/bromobenzene/anisole (98.975:0.1:0.9:0.025, v/v %) and it improved the limit of detection (LOD) by 2‐ to 10‐fold for the tested PAHs compared to those obtained with pure chlorobenzene.

CONCLUSIONS

A novel multicomponent dopant that contains 99% ethanol and 1% mixture of chlorobenzene, bromobenzene and anisole was found to be an effective dopant mixture to ionize PAHs. The developed UPLC multicomponent dopant assisted atmospheric pressure photoionization high‐resolution mass spectrometry offered a rapid non targeted screening method for detecting the PAHs at low pg/μL levels within a 5 min run time with high mass accuracy ≤4 ppm. Copyright © 2012 John Wiley & Sons, Ltd.
Systematic evaluation of the root cause of non‐linearity in liquid chromatography/tandem mass spectrometry bioanalytical assays and strategy to predict and extend the linear standard curve range
Authors: Yuan Long , Zhang Duxi , Jemal Mohammed , Aubry Anne‐Francoise
Published: May 2012

RATIONALE

The linear range of a liquid chromatography/tandem mass spectrometry (LC/MS/MS) bioanalytical assay is typically about three orders of magnitude. A broader standard curve range is favored since it can significantly reduce the time, labor and potential errors related to sample dilution – one of the bottlenecks in sample analysis. Using quadratic regression to fit the standard curve can, to a certain degree, extend the dynamic range. However, the use of a quadratic regression is controversial, particularly in regulated bioanalysis.

METHODS

A number of compounds, with different physicochemical properties and ionization efficiencies, were evaluated to understand the cause of the non‐linear behavior of the standard curve.

RESULTS

The standard curve behavior is primarily associated with the absolute analyte response but not the analyte concentration, the properties of the analyte, or the nature of the matrix when a stable‐isotope‐labeled internal standard (SIL‐IS) is used. For all the test compounds, a non‐linear curve was observed when signals exceeded a certain response, which depends on the detector used in the mass spectrometer. With typical API4000 instruments used for the experiments, this critical response level was determined to be ~1 E+6 counts per second (cps) and it was successfully used to predict the linear ranges for the test compounds. By simultaneously monitoring two selective reaction monitoring (SRM) channels of different intensity and using SIL‐IS, a linear range of five orders of magnitude was achieved.

CONCLUSIONS

In this work, the root cause of the non‐linear behavior of the standard curve when using a SIL‐IS was investigated and identified. Based on the findings, an improved multiple SRM channels approach was proposed and successfully applied to obtain a linear dynamic range of five orders of magnitude for one test compound. This approach may work particularly well for LC/MS/MS bioanalytical assay of dried blood spot (DBS) samples, for which a direct dilution is cumbersome. Copyright © 2012 John Wiley & Sons, Ltd.
Cooperative control of dynamically decoupled systems via distributed model predictive control
Authors: Müller Matthias A. , Reble Marcus , Allgöwer Frank
Published: May 2012

In this paper, we propose a general framework for distributed model predictive control of discrete‐time nonlinear systems with decoupled dynamics but subject to coupled constraints and a common cooperative task. To ensure recursive feasibility and convergence to the desired cooperative goal, the systems optimize a local cost function in a sequential order, whereas only neighbor‐to‐neighbor communication is allowed. In contrast to most of the existing distributed model predictive control schemes in the literature, we do not necessarily consider the stabilization of an a priori known set point. Instead, also other cooperative control tasks such as consensus and synchronization problems can be handled within the proposed framework. In particular, one of our main contributions is to show how for the latter case the terminal cost functions and the terminal region can be suitably defined and computed. Furthermore, we illustrate our results with simulation examples. Copyright © 2012 John Wiley & Sons, Ltd.
The superhydrophobic properties of ZrO2 induced by laser irradiation
Authors: Zhao Yan , Xie Sijing , Jiang Yijian
Published: May 2012

The stable superhydrophobic surface of the ZrO2 substrate could be conveniently and rapidly prepared by KrF laser irradiation. With different laser energy density, the static water contact angle (CA) increased from 72° to approximately 151°. It was found that the formation of micro–nano fluctuant geometry surface structure was the dominant factor to the hydrophobic property after laser irradiation. When the laser‐irradiated sample annealed at O2 atmosphere, formation of oxygen‐related defects with high surface free energy could make the CA decrease abruptly at the beginning. After being stored at ambient atmosphere, the CA would reconvert to the value of the freshly irradiated sample gradually. Copyright © 2012 John Wiley & Sons, Ltd.
A telematics service discovery platform using the distributed peer‐to‐peer networking system
Authors: Huang Chung‐Ming , Yang Chia‐Ching , Tseng Chun‐Yu
Published: May 2012

In this paper, a distributed telematics peer‐to‐peer networking system is proposed to provide an efficient and feasible service discovery mechanism for mobile users. When mobile users travel on the road, they may request for some services from service providers to meet their demands. Mobile users in vehicles are assumed to go through a lot of regions, in which each region is associated with a region server. Related information of all service providers in a region is stored in its region server, and each region server is in charge of the service discovery requests from all vehicles located in its region. This paper focuses on the issues of developing a distributed peer‐to‐peer telematics service discovery networking system over the vehicular network environment for mobile users. To provide the communication mechanism for telematics service discovery among region server, mobile users, and service providers, the Telematics Service Markup Language is proposed. According to clients' demands, three types of query scenarios are proposed, which are (1) reference point based query, (2) continual query, and (3) route‐based query. Finally, we present usage examples and system implementation of distributed telematics peer‐to‐peer. Copyright © 2012 John Wiley & Sons, Ltd.
Cyclic Deformation of Powder Metallurgy Stainless Steel/Mg‐PSZ Composite Materials
Authors: Glage Alexander , Martin Stefan , Decker Sabine , Weigelt Christian , Junghanns Martin , Aneziris Christos G. , Martin Ulrich , Krüger Lutz , Biermann Horst
Published: May 2012

In this study, the low‐cycle fatigue (LCF) behavior of powder metallurgy stainless steel/MgO partially stabilized zirconia (Mg‐PSZ) composite materials is presented. The steel matrix based on conventional AISI 304 steel (1.4301) is reinforced with Mg‐PSZ. The investigated composite materials were manufactured using the spark plasma sintering (SPS) technique. Total strain‐controlled LCF tests were performed on materials containing 0, 5, and 10 vol% Mg‐PSZ, respectively, in order to evaluate the influence of the ceramic reinforcement. Electron backscatter diffraction (EBSD) measurements were applied to identify the locations where the martensitic phase transformations in the steel matrix and stress‐assisted as well as athermal martensitic phase transformations of the Mg‐PSZ ceramic reinforcement take place. The resulting cyclic deformation behavior is correlated with the microstructural features of the composite material.
Determination of structural changes in microwaved rice starch using Fourier transform infrared and Raman spectroscopy
Authors: Fan Daming , Ma Wenrui , Wang Liyun , Huang Jianlian , Zhao Jianxin , Zhang Hao , Chen Wei
Published: May 2012

FTIR and confocal laser micro‐Raman spectroscopy methods were used to investigate the differences in chemical bond types, bond energy, and skeleton connection system between rice starch heated in a microwave and rice starch heated rapidly using a traditional method. The temperature of the peak absorption position of CH mode vibration of microwaved sample was lower and the temperature of peak position of CO related mode vibration on skeleton of microwaved sample were higher than those of the rapid heating sample, but there were no changes to other skeletal mode vibrations such as glycosidic linkage and pyranose ring. Overall, microwave‐heat treatment did not change the type of chemical groups in starch molecules, and induce the formation of new chemical group bonds, or change the way that they interact with each other in rice starch. Furthermore, the vibrational energy of the chemical‐bond of microwave‐treated rice starch changes gradually during the heating process.
The Flk1-Cre-Mediated Deletion of ETV2 Defines Its Narrow Temporal Requirement During Embryonic Hematopoietic Development
Authors: Wareing Sarah , Mazan Andrzej , Pearson Stella , Göttgens Berthold , Lacaud Georges , Kouskoff Valerie
Published: May 2012

During embryonic development, the emergence of hematopoiesis and vasculogenesis is tightly associated, with many transcription factors implicated in both developmental processes. Among those factors, ETV2 acts at the top of the hierarchy and controls the formation of both lineages. However, it is not known at which stage of mesoderm development ETV2 is acting and whether ETV2 activity is further required once mesodermal precursors have been specified to the hematopoietic and endothelial fates. In this study, we characterize the developmental window during which ETV2 expression is required for hematopoietic and endothelial development. Using cre-mediated deletion of ETV2, we demonstrate that ETV2 is acting prior to or at the time of FLK1 expression in mesodermal precursors to initiate the hematopoietic and endothelial program. Using the in vitro differentiation of embryonic stem cells as a model system, we further show that ETV2 re-expression in Etv2−/− Flk1-negative precursors drives hematopoiesis specification and switches on the expression of most genes known to be implicated in hematopoietic and endothelial development. Among the downstream targets of ETV2, we identify the transcription factors SCL, GATA2, and FLI1 known to operate a recursive loop controlling hematopoietic development. Surprisingly, SCL re-expression in Etv2−/− cells fully rescues hematopoiesis, while the re-expression of FLI1 or GATA2 promotes only a very limited rescue. Altogether, our data establish that ETV2 is required very transiently to specify mesodermal precursors to hematopoiesis and vasculogenesis and that SCL is one of the key downstream targets of ETV2 in controlling hematopoietic specification.
An optimal cooperative spectrum sensing strategy with exponential primary link traffic
Authors: Wang Qian , Yue Dian‐Wu , Yuan Jinhong
Published: May 2012

In this paper, we investigate the optimal sensing settings for a cognitive radio (CR) network consisting a number of CR users and a fusion center (FC). Our objective is to maximize the channel utilization under the constraint that the signals from the primary user (PU) are sufficiently protected. We focus on the utilization of the channel in which PUs dynamically enter the network with burst nature. Thus, we apply the average error probability (AEP) as the metric of channel utilization. Moreover, in order to protect the PU signal from being interfered, the missing detection probability is applied as the constraint function. Assuming that counting rules are utilized in the FC, we derive the false alarm probability, the missing detection probability, and the AEP in the maximum a posteriori (MAP) fashion. Then, after proving the monotonic properties of the objective function and the constraint function, we propose an efficient algorithm named Algorithm I that can derive the optimal settings for maximizing the channel utilization. Moreover, a simplified algorithm named Algorithm II is also proposed to minimize the AEP, supposing that perfect synchronization exists between the CR users and the PU. Finally, we show our numerical results and compare our optimal results with those found by exhaustive searches. We conclude that our Algorithm I produces optimal results very close to those found by exhaustive searches. Performance comparison between Algorithms I and II is also provided in terms of the AEP and the probability of missing detection. Copyright © 2012 John Wiley & Sons, Ltd.
The representation of self and person knowledge in the medial prefrontal cortex
Authors: Wagner Dylan D. , Haxby James V. , Heatherton Todd F.
Published: May 2012

Nearly 40 years ago, social psychologists began applying the information processing framework of cognitive psychology to the question of how humans understand and represent knowledge about themselves and others. This approach gave rise to the immensely successful field of social cognition and fundamentally changed the way in which social psychological phenomena are studied. More recently, social scientists of many stripes have turned to the methods of cognitive neuroscience to understand the neural basis of social cognition. A pervasive finding from this research is that social knowledge, be it about one's self or of others, is represented in the medial prefrontal cortex (MPFC). This review focuses on the social cognitive neuroscience of self and person knowledge in the MPFC. We begin with a brief historical overview of social cognition, followed by a review of recent and influential research on the brain basis of self and person knowledge. In the latter half of this review, we discuss the role of familiarity and similarity in person perception and of spontaneous processes in self and other‐referential cognition. Throughout, we discuss the myriad ways in which the social cognitive neuroscience approach has provided new insights into the nature and structure of self and person knowledge. WIREs Cogn Sci 2012, 3:451–470. doi: 10.1002/wcs.1183

This article is categorized under:

Neuroscience > Cognition
Control of germline stem cell self‐renewal and differentiation in the Drosophila ovary: concerted actions of niche signals and intrinsic factors
Authors: Ting Xie
Published: May 2012

In the Drosophila ovary, germline stem cells (GSCs) physically interact with their niche composed of terminal filament cells, cap cells, and possibly GSC‐contacting escort cells (ECs). A GSC divides to generate a self‐renewing stem cell that remains in the niche and a differentiating daughter that moves away from the niche. The GSC niche provides a bone morphogenetic protein (BMP) signal that maintains GSC self‐renewal by preventing stem cell differentiation via repression of the differentiation‐promoting gene bag of marbles (bam). In addition, it expresses E‐cadherin, which mediates cell adhesion for anchoring GSCs in the niche, enabling continuous self‐renewal. GSCs themselves also express different classes of intrinsic factors, including signal transducers, transcription factors, chromatin remodeling factors, translation regulators, and miRNAs, which control self‐renewal by strengthening interactions with the niche and repressing various differentiation pathways. Differentiated GSC daughters, known as cystoblasts (CBs), also express distinct classes of intrinsic factors to inhibit self‐renewal and promote germ cell differentiation. Surprisingly, GSC progeny are also dependent on their surrounding ECs for proper differentiation at least partly by preventing BMP from diffusing to the differentiated germ cell zone and by repressing ectopic BMP expression. Therefore, both GSC self‐renewal and CB differentiation are controlled by collaborative actions of extrinsic signals and intrinsic factors. WIREs Dev Biol 2013, 2:261–273. doi: 10.1002/wdev.60

This article is categorized under:

Invertebrate Organogenesis > Flies

Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches
Development of the cerebellum: from gene expression patterns to circuit maps
Authors: White Joshua J. , Sillitoe Roy V.
Published: May 2012

The internal structure of the cerebellum reflects an intriguing paradox; its cytoarchitecture is relatively simple and repeated throughout, yet the connections between its neurons are wired into a complex array of gene expression domains and functional circuits. The developmental mechanisms that coordinate the establishment of cerebellar structure and circuitry provide a powerful model for understanding how functional brain networks are formed. Two primary germinal zones generate the cells that make up the cerebellum. Each zone expresses a specific set of genes that establish the cell lineages within the cerebellar anlage. Then, cohorts of differentiated projection neurons and interneuron progenitors migrate into the developing cerebellum. Thereafter, a number of remarkable patterning events occur including transformation of the smooth cerebellar surface into an intricately patterned series of folds, formation of three distinct cellular layers, and the demarcation of parasagittal gene expression domains. Together, these structural and molecular organizations are thought to support the proper connectivity between incoming afferent projections and their target cells. After birth, genetic programs and neural activity repattern synaptic connections into topographic neural networks called modules, which are organized around a longitudinal zone plan and are defined by their molecular, anatomic, and functional properties. WIREs Dev Biol 2013, 2:149–164. doi: 10.1002/wdev.65

This article is categorized under:

Nervous System Development > Vertebrates: Regional Development
W4Br10 Cluster Intermediates in the Solid State Nucleation of W6Br12
Authors: Ströbele Markus , Meyer H.‐Jürgen
Published: May 2012

The new adduct W4Br10·2SbBr3 and the new binary compound W4Br10 were obtained as products in a reaction cascade in which WBr6 was reacted with elemental antimony at successively increased temperatures. The crystal structures of both compounds were refined from X‐ray powder diffraction data and their electronic structures were analyzed by MO calculations. The cluster compounds W4Br10·2SbBr3 and W4Br10 appear as intermediates in the solid state nucleation of W6Br12. The overall reaction cascade involves tungsten clusters having tetrahedral (W4), square pyramidal (W5) and finally octahedral (W6) cluster cores.
29Si NMR Shielding Tensors in Triphenylsilanes – 29Si Solid State NMR Experiments and DFT‐IGLO Calculations
Authors: Brendler Erica , Heine Thomas , Seichter Wilhelm , Wagler Jörg , Witter Raiker
Published: May 2012

29Si NMR shielding tensors of a series of triphenylsilanes Ph3SiR with R = Ph, Me, F, Cl, Br, OH, OMe, SH, NH2, SiPh3, C≡CPh were determined from 29Si CP/MAS spectra recorded at low spinning rates. In addition the principal components of the shielding tensor were calculated employing the DFT‐IGLO method. For most silanes experimental and calculated values are in good accordance. Larger differences were observed for systems with hydrogen bridge forming substituents and the halides bromide and chloride. In some of the spectra the shielding information interfered with residual dipolar couplings. The different contributions of the various substituents to the principal components of the shielding tensor and the orientation of the tensor within the molecules are discussed and compared for the compounds under investigation.
Long‐term Survival in Hilar Cholangiocarcinoma also Possible in Unresectable Patients
Authors: Ruys Anthony T. , van Haelst Steven , Busch Olivier R. , Rauws Erik A. , Gouma Dirk J. , van Gulik Thomas M.
Published: May 2012

Background

Radical resection remains the only curative treatment for hilar cholangiocarcinoma (HCCA). Only a limited proportion of patients, however, are eligible for resection. The survival and prognostic factors of these patients are largely unknown. The aim of this study was to evaluate survival and prognostic factors in unresectable patients presenting with HCCA.

Methods

We performed a cohort study of the denominator of HCCA patients seen in a tertiary referral center between March 2003 and March 2009. Demographics, treatment, pathology results, and survival were analyzed.

Results

A total of 217 patients with suspected HCCA were identified. Ninety‐five patients (40 %) underwent laparotomy, and in 57 (63 %) of these patients resection was performed. Overall median and 5‐year survival of resected patients were 37 months and 43 %, respectively, as compared to 13 months and 7 % in unresectable patients. In unresectable patients, median survival was better in patients with locally advanced disease (16 months) as compared to patients with hepatic and extrahepatic metastases (5 and 3 months, p < 0.001). Of the 160 unresectable patients, 17 (10 %) survived longer than 3 years.

Conclusion

Of the patients presenting with HCCA in our center, 26 % proved resectable. The 7 % long‐term survival rate of unresectable patients is remarkable and emphasizes the indolent growth of some of these tumors. Patients with metastases had a much worse prognosis with a median of 4 months.
Pontocerebellar hypoplasia type 6 caused by mutations in RARS2: definition of the clinical spectrum and molecular findings in five patients
Authors: Cassandrini Denise , Cilio Maria Roberta , Bianchi Marzia , Doimo Mara , Balestri Martina , Tessa Alessandra , Rizza Teresa , Sartori Geppo , Meschini Maria Chiara , Nesti Claudia , Tozzi Giulia , Petruzzella Vittoria , Piemonte Fiorella , Bisceglia Luigi , Bruno Claudio , Dionisi‐Vici Carlo , D'Amico Adele , Fattori Fabiana , Carrozzo Rosalba , Salviati Leonardo , Santorelli Filippo M. , Bertini Enrico
Published: May 2012

Recessive mutations in the mitochondrial arginyl‐transfer RNA synthetase (RARS2) gene have been associated with early onset encephalopathy with signs of oxidative phosphorylation defects classified as pontocerebellar hypoplasia 6. We describe clinical, neuroimaging and molecular features on five patients from three unrelated families who displayed mutations in RARS2. All patients rapidly developed a neonatal or early‐infantile epileptic encephalopathy with intractable seizures. The long‐term follow‐up revealed a virtual absence of psychomotor development, progressive microcephaly, and feeding difficulties. Mitochondrial respiratory chain enzymes in muscle and fibroblasts were normal in two. Blood and CSF lactate was abnormally elevated in all five patients at early stages while appearing only occasionally abnormal with the progression of the disease. Cerebellar vermis hypoplasia with normal aspect of the cerebral and cerebellar hemispheres appeared within the first months of life at brain MRI. In three patients follow‐up neuroimaging revealed a progressive pontocerebellar and cerebral cortical atrophy. Molecular investigations of RARS2 disclosed the c.25A>G/p.I9V and the c.1586+3A>T in family A, the c.734G>A/p.R245Q and the c.1406G>A/p.R469H in family B, and the c.721T>A/p.W241R and c.35A>G/p.Q12R in family C. Functional complementation studies in Saccharomyces cerevisiae showed that mutation MSR1‐R531H (equivalent to human p.R469H) abolished respiration whereas the MSR1‐R306Q strain (corresponding to p.R245Q) displayed a reduced growth on non‐fermentable YPG medium. Although mutations functionally disrupted yeast we found a relatively well preserved arginine aminoacylation of mitochondrial tRNA. Clinical and neuroimaging findings are important clues to raise suspicion and to reach diagnostic accuracy for RARS2 mutations considering that biochemical abnormalities may be absent in muscle biopsy.
Virtual Reality Social Cognition Training for Young Adults with High-Functioning Autism
Authors: Kandalaft Michelle R. , Didehbani Nyaz , Krawczyk Daniel C. , Allen Tandra T. , Chapman Sandra B.
Published: May 2012

Few evidence-based social interventions exist for young adults with high-functioning autism, many of whom encounter significant challenges during the transition into adulthood. The current study investigated the feasibility of an engaging Virtual Reality Social Cognition Training intervention focused on enhancing social skills, social cognition, and social functioning. Eight young adults diagnosed with high-functioning autism completed 10 sessions across 5 weeks. Significant increases on social cognitive measures of theory of mind and emotion recognition, as well as in real life social and occupational functioning were found post-training. These findings suggest that the virtual reality platform is a promising tool for improving social skills, cognition, and functioning in autism.
Report from the National Society of Genetic Counselors Service Delivery Model Task Force: A Proposal to Define Models, Components, and Modes of Referral
Authors: Cohen Stephanie A. , Gustafson Shanna L. , Marvin Monica L. , Riley Bronson D. , Uhlmann Wendy R. , Liebers S. Bonnie , Rousseau Julie A.
Published: May 2012

The Service Delivery Model Task Force (SDMTF) was appointed in 2009 by the leadership of the National Society of Genetic Counselors (NSGC) with a charge to research and assess the capacity of all existing service delivery models to improve access to genetic counseling services in the context of increasing demand for genetic testing and counseling. In approaching this charge, the SDMTF found that there were varying interpretations of what was meant by “service delivery models” and the group held extensive discussions about current practices to arrive at consensus of proposed definitions for current genetic service delivery models, modes of referral and components of service delivery. The major goal of these proposed definitions is to allow for conversations to begin to address the charge to the committee. We propose that current models of service delivery can be defined by: 1) the methods in which genetic counseling services are delivered (In‐person, Telephone, Group and Telegenetics), 2) the way they are accessed by patients (Traditional referral, Tandem, Triage, Rescue and Self‐referral) and 3) the variable components that depend upon multiple factors unique to each service setting. This report by the SDMTF provides a starting point whereby standardized terminology can be used in future studies that assess the effectiveness of these described models to overcome barriers to access to genetic counseling services.
Exploratory Bi-factor Analysis: The Oblique Case
Authors: Jennrich Robert I. , Bentler Peter M.
Published: May 2012

Bi-factor analysis is a form of confirmatory factor analysis originally introduced by Holzinger and Swineford (Psychometrika 47:41–54, 1937). The bi-factor model has a general factor, a number of group factors, and an explicit bi-factor structure. Jennrich and Bentler (Psychometrika 76:537–549, 2011) introduced an exploratory form of bi-factor analysis that does not require one to provide an explicit bi-factor structure a priori. They use exploratory factor analysis and a bifactor rotation criterion designed to produce a rotated loading matrix that has an approximate bi-factor structure. Among other things this can be used as an aid in finding an explicit bi-factor structure for use in a confirmatory bi-factor analysis. They considered only orthogonal rotation. The purpose of this paper is to consider oblique rotation and to compare it to orthogonal rotation. Because there are many more oblique rotations of an initial loading matrix than orthogonal rotations, one expects the oblique results to approximate a bi-factor structure better than orthogonal rotations and this is indeed the case. A surprising result arises when oblique bi-factor rotation methods are applied to ideal data.
Trans Isomers of EPA and DHA in Omega‐3 Products on the European Market
Authors: Sciotto Caterina , Mjøs Svein A.
Published: May 2012

The levels of trans isomers of eicosapentaenoic (EPA) acid and docosahexaenoic acid (DHA) in 77 omega‐3 products on the European market have been studied. Fatty acids were analyzed as fatty acid methyl esters by gas chromatography with a flame ionization detector, using a cyanopropyl coated stationary phase. The amount of mono‐trans EPA isomers relative to the corresponding all‐cis isomer ranged from 0.19 to 4.5 %. The corresponding values for mono‐trans DHA relative to the all‐cis isomer ranged from 0.25 to 5.9 %. There was a strong correlation between the degree of isomerization of EPA and DHA, showing that DHA was 1.26 times more isomerized than EPA. Division of the samples into different product groups showed that samples with a low degree of isomerization were found in all groups, except one. This shows that a high degree of isomerization is avoidable, and also points to deodorization of the oils as the main source of trans isomers.
LC–ESI–MS/MS Identification of Polar Lipids of Two Thermophilic Anoxybacillus Bacteria Containing a Unique Lipid Pattern
Authors: Řezanka Tomáš , Kambourova Margarita , Derekova Anna , Kolouchová Irena , Sigler Karel
Published: May 2012

Phospholipids and glycolipids from two recently described species belonging to the thermophilic genus Anoxybacillus were analyzed by liquid chromatography–electrospray tandem mass spectrometry (LC/ESI–MS/MS). Analysis of total lipids from the facultatively anaerobic A. bogrovensis on a HILIC (Hydrophilic Interaction LIquid Chromatography) column succeeded in separating diacyl‐ and plasmalogen phospholipids. The LC/ESI–MS/MS analysis of the strict aerobe A. rupiensis revealed the presence of different unique polar lipids, predominantly alanyl‐, lysyl‐, and glucosyl‐phosphatidylglycerols and cardiolipins. Each of the classes of polar lipids was then analyzed by means of the ESI–MS/MS and more than 140 molecular species of six lipid classes from A.bogrovensis and nearly 200 molecular species of nine classes of polar lipids from A. rupiensis were identified. Five classes of unidentified polar lipids were detected in both strains. Plasmalogens were thus determined for the first time in a facultatively anaerobic bacterium, i.e. A. bogrovensis.
Special Issue on the Invisible Woman
Authors: Simms Margaret C.
Published: May 2012

This brief article introduces the special issue on the Invisible Woman.
Numerical Study for the Flow and Heat Transfer in a Thin Liquid Film Over an Unsteady Stretching Sheet with Variable Fluid Properties in the Presence of Thermal Radiation
Authors: Liu I-C. , Megahed A. M.
Published: May 2012

In this paper, the effect of thermal radiation, variable viscosity and variable thermal conductivity on the flow and heat transfer of a thin liquid film over an unsteady stretching sheet is analyzed. The continuity, momentum and energy equations, which are coupled nonlinear partial differential equations, are reduced to a set of two non-linear ordinary differential equations, before being solved numerically. Results for the skin-friction coefficient, local Nusselt number, velocity profiles as well as temperature profiles are presented for different values of the governing parameters. It is found that increasing the viscosity parameter leads to a rise in the velocity near the surface of the sheet and a fall in the temperature. Furthermore, it is shown that the temperature increases due to an increase in the values of the thermal conductivity parameter and the thermal radiation parameter, while it decreases with an increase of the Prandtl number.
Adaptation and psychometric evaluation of the Italian version of the depression attitude questionnaire (DAQ)
Authors: Sighinolfi C. , Norcini Pala A. , Casini F. , Haddad M. , Berardi D. , Menchetti M.
Published: May 2012

Aims.

To validate the Italian version of the ‘depression attitude questionnaire’ (DAQ), to assess its psychometric properties and to evaluate the primary care physicians' (PCPs) opinion and attitude towards depression.

Methods.

An Italian version of the DAQ was created and then administered to a representative sample of PCPs working in the Emilia-Romagna region.

Results.

The findings derived from the Italian version of the DAQ indicated a three-factor solution (professional confidence, negative viewpoint and biological stance), broadly similar to previous studies and with acceptable fit indices. Our results showed that the PCPs consider depression as an increasingly important issue for their daily clinical practice. A large majority of them believed in the effectiveness of antidepressants and considered psychopharmacological treatment as appropriate for the PCPs to undertake. However, most PCP respondents thought that psychotherapy should be left to the specialists. Our findings suggest a prevalent orientation to the biochemical aspects of depression and the use of antidepressant treatment.

Conclusions.

The PCPs' attitude and opinion towards depression is an important aspect of their understanding and response to this common and disabling condition. The Italian version of the DAQ appears to be an appropriate and useful instrument to assist the understanding of the PCPs' views and potential need for further professional development.
Dynamic capillary pressure during water infiltration: Experiments and Green‐Ampt modeling
Authors: Pellichero Emanuele , Glantz Roland , Burns Meghan , Mallick Debjani , Hsu Shao‐Yiu , Hilpert Markus
Published: May 2012

In a recent study by Hsu and Hilpert (2011), the Green‐Ampt (GA) model for water infiltration was modified to account for a dynamic capillary pressure that depends on the wetting front velocity. In that study, the only transient flow, to which the modified GA approach was compared, was capillary rise. In this paper, transient downward infiltration experiments were performed using three different ponding depths. We demonstrated that infiltration can be effectively modeled using the modified GA approach. The parameters of the dynamic capillary pressure relationship were fitted and independent of the ponding depth. Furthermore, the experimental data could not be described accurately at early times with the classical GA approach. This was particularly evident when plotting the product between the Darcy velocity and the wetting front position against the wetting front position. In these plots, the initial unphysical infinite rate of infiltration, that occurs in the classical GA model, appears to be a primary element of inaccuracy. It was furthermore verified that the limited ability of the classical GA approach to describe the experimental data is not related to inertial forces arising during the initial phase of infiltration.
Swenson receives 2011 Geodesy Section Award: Response
Authors: Swenson Sean Claude
Published: May 2012

Sean Claude Swenson received the 2011 Geodesy Section Award at the 2011 AGU Fall Meeting, held 5–9 December in San Francisco, Calif. The award is given in recognition of major advances in geodesy
The island‐scale internal wave climate of Moorea, French Polynesia
Authors: Leichter James J. , Stokes M. Dale , Hench James L. , Witting Jan , Washburn Libe
Published: May 2012

Analysis of five‐year records of temperatures and currents collected at Moorea reveal strong internal wave activity at predominantly semi‐diurnal frequencies impacting reef slopes at depths ≥30 m around the entire island. Temperature changes of 1.5°C to 3°C are accompanied by surges of upward and onshore flow and vertical shear in onshore currents. Superimposed on annual temperature changes of approximately 3°C, internal wave activity is high from Oct–May and markedly lower from Jun–Sep. The offshore pycnocline is broadly distributed with continuous stratification to at least 500 m depth, and a subsurface fluorescence maximum above the strong nutricline at approximately 200 m. Minimum buoyancy periods range from 4.8 to 6 min, with the maximum density gradient occurring at 50 to 60 m depth in summer and deepening to approximately 150 to 200 m in winter. The bottom slope angle around all of Moorea is super‐critical relative to the vertical stratification angle suggesting that energy propagating into shallow water is only a portion of total incident internal wave energy. Vertical gradient Richardson numbers indicate dominance by density stability relative to current shear with relatively limited diapycnal mixing. Coherence and lagged cross‐correlation of semi‐diurnal temperature variation indicate complex patterns of inter‐site arrival of internal waves and no clear coherence or lagged correlation relationships among island sides. Semi‐diurnal and high frequency internal wave packets likely arrive on Moorea from a combination of local and distant sources and may have important impacts for nutrient and particle fluxes in deep reef environments.
Highly sensitive thermal conductivity measurements of suspended membranes (SiN and diamond) using a 3ω-Völklein method
Authors: Sikora A. , Ftouni H. , Richard J. , Hébert C. , Eon D. , Omnès F. , Bourgeois O.
Published: May 2012

A suspended system for measuring the thermal properties of membranes is presented. The sensitive thermal measurement is based on the 3ω dynamic method coupled to a Völklein geometry. The device obtained using micro-machining processes allows the measurement of the in-plane thermal conductivity of a membrane with a sensitivity of less than 10 nW/K (+/−5 × 10−3 Wm−1 K−1 at room temperature) and a very high resolution (ΔK/K = 10−3). A transducer (heater/thermometer) centered on the membrane is used to create an oscillation of the heat flux and to measure the temperature oscillation at the third harmonic using a Wheatstone bridge set-up. Power as low as 0.1 nW has been measured at room temperature. The method has been applied to measure thermal properties of low stress silicon nitride and polycrystalline diamond membranes with thickness ranging from 100 nm to 400 nm. The thermal conductivity measured on the polycrystalline diamond membrane support a significant grain size effect on the thermal transport.
Time-dependent coupled harmonic oscillators
Authors: Macedo D. X. , Guedes I.
Published: May 2012

In this paper we use a canonical and a unitary transformation along with the Lewis and Riesenfeld invariant method to obtain the quantum states of a general system of two time-dependent statically coupled harmonic oscillators. The wave function obtained is written in terms of a c-number quantity, which is solution of the Milne-Pinney equation. We consider three different systems of time-dependent coupled oscillators, and for each one we solve the respective Milne-Pinney equation and discuss how the uncertainty product evolves with time.
Thickness dependent magnetic properties of amorphous FeTaC films
Authors: Singh Akhilesh K. , Kisan Bhagaban , Mishra Debabrata , Perumal A.
Published: May 2012

We report on the study of thickness and temperature dependent magnetic properties of amorphous FeTaC (t = 20–200 nm) thin films prepared on thermally oxidized Si substrate at ambient temperature. Room temperature coercivity remains constant (∼1.5 Oe) for t between 20 and 50 nm, but increases rapidly (>18 Oe) when t > 50 nm. Also, the shape of M-H loop changes from rectangular to flat loop with increasing film thickness; and at larger thicknesses (>50 nm), the central range of constant slope in the flat loop extended largely along with the enlargement of hysteresis around the origin. This is mainly due to the development of perpendicular anisotropy with increasing the film thickness causing a transition from in-plane orientations of the spins to a magnetic stripe domain structure, which degrades the magnetic properties at larger thickness. Low temperature thermomagnetization curves obtained under zero-field-cooled (ZFC) and field-cooled (FC) conditions depicts a bifurcation between ZFC and FC data at larger thickness films. With decreasing t, the bifurcation point shifted to lower temperatures and almost disappeared for t ≤ 50 nm. On the other hand, the high temperature magnetization data reveal a considerable increase in Curie temperature with decreasing film thickness and the magnetic susceptibility critical exponent γ exhibits a thickness dependent behavior. The observed results are discussed on the basis of two-layer model, and the development of perpendicular anisotropy and magnetic disorder with increasing FeTaC film thickness.
Photoluminescence quenching in cobalt doped ZnO nanocrystals
Authors: Yamamoto Sekika
Published: May 2012

Influence of cobalt doping on the luminescence properties of ZnO nanocrystals with average diameter of 3.0 nm is investigated. Time resolved measurements at 20 K show that the dark exciton luminescence is completely lost in the nanocrystals doped with cobalt, while the perturbed luminescence with slight red shift survives and exhibits a non-exponential decay curve reflecting random distribution of cobalt atoms. By analyzing the non-exponentiality, the increase of the decay rate of the band-edge luminescence induced by the inclusion of single cobalt atom is estimated to be 0.012 ps-1.
Mapping inter-element coupling in metamaterials: Scaling down to infrared
Authors: Tatartschuk E. , Gneiding N. , Hesmer F. , Radkovskaya A. , Shamonina E.
Published: May 2012

The coupling between arbitrarily positioned and oriented split ring resonators is investigated up to THz frequencies. Two different analytical approaches are used, one based on circuits and the other on field quantities that includes retardation. These are supplemented by numerical simulations and experiments in the GHz range, and by simulations in the THz range. The field approach makes it possible to determine separately the electric and magnetic coupling coefficients which, depending on orientation, may reinforce or may cancel each other. Maps of coupling are produced for arbitrary orientations of two co-planar split rings resonant at around 2 GHz and then with the geometry scaled down to be resonant at around 100 THz. We prove that the inertia of electrons at high frequencies results in a dramatic change in the maps of coupling, due to reduction of the magnetic contribution. Our approach could facilitate the design of metamaterials in a wide frequency range up to the saturation of the resonant frequency.
Central electron temperature estimations of TJ-II neutral beam injection heated plasmas based on the soft x ray multi-foil technique
Authors: Baião D. , Medina F. , Ochando M. , McCarthy K. , Tabarés F. , Pastor I. , Varandas C.
Published: May 2012

The core electron temperature (Te0) of neutral beam heated plasmas is determined in TJ-II stellarator by using soft x ray detectors with beryllium filters of different thickness, based on the method known as the foil absorption technique. Te0 estimations are done with the impurity code IONEQ, making use of complementary information from the TJ-II soft x ray tomography and the VUV survey diagnostics. When considering the actual electron density and temperature profile shapes, an acceptable agreement is found with Thomson scattering measurements for 8 different magnetic configurations. The impact of the use of both neutral beam injectors on the Te0 measurements is addressed. Also, the behaviour of Te0 during spontaneous profile transitions is presented.
Genes, morphology, development and photosynthetic ability support the resurrection of Elysia cornigera (Heterobranchia:Plakobranchoidea) as distinct from the 'solar-powered' sea slug, E. timida
Authors: Krug Patrick J. , Händeler Katharina , Vendetti Jann
Published: May 2012

Some groups of marine heterobranch sea slugs (formerly Opisthobranchia) have few discrete characters or hard parts and many ‘cosmopolitan’ species, suggesting an overly conservative taxonomy in need of integrative approaches. Many herbivorous sea slugs in the clade Sacoglossa retain algal chloroplasts that remain functionally photosynthetic for 1–2 weeks, but at least four species can sustain chloroplasts for several months. To better understand the origins of long-term kleptoplasty, we performed an integrative study of the highly photosynthetic species Elysia timida from the Mediterranean and Caribbean populations that were described as E. cornigera but later synonymised with E. timida. Nominal E. cornigera were distinct in their anatomy and aspects of larval development, and had dramatically reduced chloroplast retention compared with E. timida. Mean divergence at three genetic loci was determined for ten pairs of sister species in the genus Elysia, confirming that E. cornigera and E. timida have species level differences. Both taxa had a high degree of population genetic subdivision, but among-population genetic distances were far less than interspecific divergence. In an integrative taxonomic framework, E. cornigera is thus restored to species rank and fully redescribed, and baseline molecular data are presented for evaluating species level differences in the Sacoglossa.