bluuebunny/crossref_metadata_2025 huggingface dataset:
Origin of the torus mandibularis: An embryological hypothesis
Authors: Rodríguez‐Vázquez José Francisco , Sakiyama Koji , Verdugo‐López Samuel , Amano Osamu , Murakami Gen , Abe Shinichi
Published: June 2013

Torus mandibularis, a well‐known protuberance in the dental field, has been defined as a hyperostosis in the lingual aspect of the body of the mandible above the mylohyoid line. However, the origin of the torus mandibularis has not yet been clarified. The aim of this study was to provide a better understanding on the origin of the torus in view of the specific development of Meckel's cartilage at the site corresponding to the adult torus. A total of 40 mid‐term human fetuses at 7–16 weeks of gestation were examined. The 10–13 weeks stage corresponded to the critical period in which Meckel's cartilage with endochondral ossification underwent a bending at the beginning of the intramandibular course. At the level of mental foramen, which was located between the deciduous canine and the first deciduous molar germs, the medial lamina of the mandible protruded medially to reach Meckel's cartilage. Thus, the medial lamina covered the posterior and superior aspect of the bending Meckel's cartilage just above the attachment of the developing mylohyoid muscle (i.e., in the oral cavity). We considered a bony prominence, which composed the protruding medial lamina and the bending Meckel's cartilage as the fetal origin of the torus mandibularis. A new theory is proposed for the origin of the torus mandibularis based on the existence of an anlage formed during the development of the mandible, variable in morphology and size, but always constant. Clin. Anat. 26:944–952, 2013. © 2013 Wiley Periodicals, Inc.
The subparietal and parietooccipital sulci: An anatomical study
Authors: Gürer Bora , Bozkurt Melih , Neves Gabriel , Cikla Ulaş , Hananya Tomer , Antar Veysel , Salamat Shahriar , Başkaya Mustafa K.
Published: June 2013

The subparietal and parietooccipital sulci are both located on the medial surface of the brain. Both of these sulci reveal significant variability in pattern and complexity. Both subparietal and parietooccipital sulci play an important role as surgical landmarks using posterior interhemispheric parietooccipital approach to lesions located adjacent to the ventricular trigon deep to the cingulate gyrus. The aim of this study is to analyze variations in the patterns of the subparietal and parietooccipital sulci and to emphasize their surgical importance. Fifty‐six formalin‐fixed cadaveric cerebral hemispheres from 28 adult humans are examined. Subparietal and parietal sulci patterns, variations and their relationship with the cingulate sulcus are studied according to the terminology introduced by Ono et al. The H‐pattern was observed in 50% (n = 28) of all hemispheres, being the most common pattern of the subparietal sulcus. The Straight pattern was observed in the 30.4% (n = 17) of all hemispheres, being the most common pattern of the parietooccipital sulcus. Furthermore, more detailed results among the patterns, connections, side branches and the relationship with the adjacent sulci are given. Our study further confirms the complexities in the patterns of the subparietal and parietooccipital sulci and demonstrates that these sulci fall within an expected range of variations. Better knowledge of these variations will further help neurosurgeons to navigate easily during approaches involving the medial surface of the parietal lobe. Clin. Anat. 26:667–674, 2013. © 2013 Wiley Periodicals, Inc.
Unprotected carotid artery stenting in modern practice
Authors: Giri Jay , Yeh Robert W. , Kennedy Kevin F. , Hawkins Beau M. , Weinberg Ido , Weinberg Mitchell D. , Parikh Sahil A. , Garasic Joseph , Jaff Michael R. , White Christopher J. , Rosenfield Kenneth
Published: June 2013

Background & Purpose

Embolic protection devices (EPD) may provide a mechanism to reduce peri‐procedural strokes. They are advocated by consensus guidelines and mandated for Medicare reimbursement. However, outcomes data remain mixed. We aimed to characterize the population of patients undergoing unprotected carotid artery stenting (CAS) and assess the utility of distal filter EPD (F‐EPD) in elective CAS.

Methods

We analyzed patients enrolled in the CARE Registry® undergoing CAS between May, 2005 and January, 2012. We assessed the relationship between distal F‐EPD use versus no use (No‐EPD) and the composite of in‐hospital death or stroke (MAE) in unadjusted and 1:3 propensity‐matched analyses.

Results

Embolic protection was not attempted in a total of 579 out of 13,263 cases performed (4.4%). Patients in the No‐EPD group had worse preprocedure neurologic risk factors including higher rates of acute evolving stroke, prior TIA/stroke, symptomatic lesion status, spontaneous carotid artery dissection, and use of general anesthesia intraprocedurally (all Standardized Differences{sd} >10). After exclusion of nonelective cases there was no significant difference in MAE between the No‐EPD and F‐EPD groups (1.6% vs. 2.3%, sd = 4.72). Additionally, after propensity matching, rates of MAE did not differ between the No‐EPD (n = 355) and F‐EPD (n = 1065) groups (1.7% vs. 2.5%, sd = 5.87).

Conclusions

Patients selected to undergo unprotected CAS in contemporary practice have high rates of adverse preprocedure neurologic risk factors. Our propensity‐matched analysis did not demonstrate evidence of significant benefit or harm associated with use of F‐EPD in elective CAS patients. © 2013 Wiley Periodicals, Inc.
Enantioselective Syntheses of the Proposed Structures of Kopeolin and Kopeolone
Authors: Miquet Stéphanie , Vanthuyne Nicolas , Brémond Paul , Audran Gérard
Published: June 2013

The first total syntheses of the proposed structures of kopeolin (1) and kopeolone (3) have been achieved from a common enantiopure chiral building block obtained by a chemoenzymatic enantioconvergent methodology. The syntheses feature two key steps: a one‐pot reduction/diastereoselective protonation followed by a highly diastereoselective addition of an organocerate. The synthetic structures were fully characterized and all stereocenters were confirmed. The results show that the two previously reported structures were not assigned correctly, and suggest an initial structural misassignment during the isolation of the natural products. Thus, two revised structures, 1′ for kopeolin and 3′ for kopeolone, are proposed.
Effect of liquid level and agitator pumping direction on turbulent blend times
Authors: Myers Kevin J. , Jones Jeremy K. , Janz Eric E. , Fasano Julian B.
Published: June 2013

With the impeller placed low in the tank (C/T = 1/3), turbulent blend times produced by radial‐flow and down‐pumping axial‐flow impellers generally increase slowly with increasing liquid level in shorter batches (Z/T < 1), but increase dramatically in taller batches (Z/T > 1). The turbulent blend times produced by up‐pumping axial‐flow impellers increase slowly with increasing liquid level across the entire spectrum of liquid levels that were studied (up to Z/T = 1.75). This can lead to down‐pumping blend times that are twice as long as those with up‐pumping operation. These differences can be explained by differences in the velocity field in the agitated vessel. Further, the down‐pumping mode can produce blend times in tall tanks that are comparable to those of the up‐pumping mode if the down‐pumping impeller is placed high in the batch such that its discharge flow is directed into the bulk of the liquid.
An overview of the kinetics and catalysis of hydrogen storage on organic liquids
Authors: Sotoodeh Farnaz , Smith Kevin J.
Published: June 2013

The potential for chemical H2 storage on liquid organic hydrogen carriers (LOHCs) has focused attention on the catalytic reactions needed to store and release H2 from the LOHCs. Herein we review our recent studies on the use of N‐ethylcarbazole and carbazole as LOHCs. Experimental data show that the hydrogenation reactions are relatively facile, although N‐ethylcarbazole hydrogenates 10×'s faster than carbazole on a 5 wt% Ru/Al2O3 catalyst at 150°C. Dehydrogenation of dodecahydro‐N‐ethylcarbazole is more difficult than hydrogenation and is structure sensitive on Pd catalysts. Maximum activity and 100% selectivity to the completely dehydrogenated product, N‐ethylcarbazole, was achieved over a 4 wt% Pd/SiO2 catalyst with dPd ∼ 9 nm. The dehydrogenation TOF of dodecahydrocarbazole and dodecahydrofluorene were much lower than dodecahydro‐N‐ethylcarbazole. DFT was used to identify the dehydrogenation mechanism and explain the experimental observations. Both theoretical and experimental results lead to the conclusion that dodecahydro‐N‐ethylcarbazole is a better H2storage candidate than dodecahydrocarbazole.
Decision tree building on multi‐core using FastFlow
Authors: Aldinucci Marco , Ruggieri Salvatore , Torquati Massimo
Published: June 2013

The whole computer hardware industry embraced the multi‐core. The extreme optimisation of sequential algorithms is then no longer sufficient to squeeze the real machine power, which can be only exploited via thread‐level parallelism. Decision tree algorithms exhibit natural concurrency that makes them suitable to be parallelised. This paper presents an in‐depth study of the parallelisation of an implementation of the C4.5 algorithm for multi‐core architectures. We characterise elapsed time lower bounds for the forms of parallelisations adopted and achieve close to optimal performance. Our implementation is based on the FastFlow parallel programming environment, and it requires minimal changes to the original sequential code. Copyright © 2013 John Wiley & Sons, Ltd.
An iterative parameter estimation method for biological systems and its parallel implementation
Authors: Yang Xian , Guo Yike , Guo Li
Published: June 2013

One difficulty in building a mechanistic model of biological systems lies in determining correct parameter values. This paper proposes a novel parameter estimation method to infer unknown parameters, such as kinetic rates, from noisy experimental observations. Derived from the approximate Bayesian computation sequential Monte Carlo algorithm, our method predicts the distribution of each parameter rather than a single value via several intermediate distributions. Motivated by the computational intensity of the method, we improve the approximate Bayesian computation sequential Monte Carlo method in two aspects. First, to increase the efficiency, a windowing method is developed to reduce the parameter‐searching space, and an adaptive sampling weight mechanism is introduced to make the intermediate distributions converge to the target distributions in a much quicker manner. Second, to speed up the estimation process, we implement our method in a parallel computing environment to speed up the sampling process. Copyright © 2013 John Wiley & Sons, Ltd.
A highly sensitive and ultra low‐power forward body biasing circuit to overcome severe process, voltage and temperature variations and extreme voltage scaling
Authors: Radfar Mohsen , Shah Kriyang , Singh Jack
Published: June 2013

Dynamic voltage scaling is one of the most popular methods used to reduce energy consumption in today's digital electronic systems. However, addressing process, voltage and temperature variations at subthreshold voltages has become an inevitable procedure. Using a variation‐sensitive and ultra low‐power design, this paper proposed a novel technique capable of sensing and responding to process, voltage and temperature variations as well as dynamic voltage scaling by providing an appropriate forward body bias so that energy‐delay product of the whole system was improved. Theoretical analysis for process variation probability, confirmed by post‐layout HSPICE (Synopsys, Inc., Mountain View, CA) simulations for an 8‐bit pipelined Kogge–Stone adder, showed that the circuit performance was enhanced in severe variations and extreme voltage scaling situation. For this adder, for example, assuming a voltage scaling from 0.8 to 0.3 V and temperature changes of −15 to 75 °C, the proposed technique brought about a seven times less delay variation, whereas energy‐delay product improved by 23% compared with a zero body biased adder. Copyright © 2013 John Wiley & Sons, Ltd.
Double‐layer P2P networks supporting semantic search and keeping scalability
Authors: Liu Xianru , Wang Shiguo , Ji Hong
Published: June 2013

In peer‐to‐peer (P2P) networks, with the aim to support semantic search and keep scalability at the same time, a novel double‐layer P2P protocol is proposed. Firstly, keywords representing resource characteristics are compressed into bloom filters and structured P2P layer is constructed. Secondly, through analyzing one's bloom filters, each node extracts its interest, which is represented by a characteristic vector V. After obtaining common interest among nodes through comparing their Vs, a small‐world model is constructed, and another unstructured P2P layer is obtained. Consequently, on the basis of the decentralized architecture, a double‐layer semantic search P2P protocol is structured. When objective resource is being located, its similarity to local interest is used to determine whether it should be located in unstructured P2P semantic layer or structured layer adaptively, which not only improves search efficiency but also supports semantic location more widely. Copyright © 2013 John Wiley & Sons, Ltd.
Investigation of ‘equal displacement’ rule for bridges subjected to differential support motions
Authors: Konakli Katerina , Der Kiureghian Armen
Published: June 2013

The ‘equal displacement’ rule is employed in seismic design practice to predict inelastic displacements from analyses of the corresponding linear elastic structural models. The accuracy and limitations of this rule have been investigated for ordinary structures but not for bridges subjected to spatially varying ground motions. The present study investigates this rule for moderate levels of inelastic behavior for four highway bridges in California accounting for the effects of spatial variability of the support motions due to incoherence, wave passage and differential site response. The bridge models vary significantly as to their fundamental periods and their overall configurations. Statistical analyses of pier‐drift responses are performed using as input simulated arrays of nonstationary ground motions in accordance with prescribed coherency models. It is found that the ‘equal displacement’ rule is fairly accurate for cases when the fundamental period of the bridge is longer than the transition period between the acceleration‐controlled and velocity‐controlled ranges of the response spectrum. Otherwise, the rule is non‐conservative for cases with large ductility factors and conservative for cases with small ductility factors. Wave passage and incoherence tend to reduce ratios of mean peak inelastic to elastic pier drifts, whereas incorporation of the differential site‐response effect by locating piers on softer soils tends to increase the same ratios. Mild or moderate positive correlation between these ratios and ductility demands is observed in most cases. Effects of spatial variability are more pronounced for longer and stiffer bridges. Copyright © 2013 John Wiley & Sons, Ltd.
Interactive effects of pesticide mixtures, predators, and environmental regimes on the toxicity of two pesticides to red-eyed tree frog larvae
Authors: Johnson Laura A. , Welch Bill , Whitfield Steven M.
Published: June 2013

Global amphibian declines have many corroborative causes, and the use of pesticides in agriculture is a likely contributor. In places with high pesticide usage, such as Costa Rica, agrochemical pesticides may interact with other factors to contribute to rapid species losses. Classical ecotoxicological studies rarely address the effects of a pesticide in combination with other stressors. The present study investigated the synergistic roles of 2 pesticides (chlorothalonil and endosulfan), predator stress, and environmental regimes (controlled laboratory environments versus ambient conditions) on the survival of red-eyed tree frog larvae (Agalychnis callidryas). No synergistic effects of pesticide mixtures or predator stress were found on the toxicity of either chlorothalonil or endosulfan. Both pesticides, however, were considerably more toxic under realistic ambient temperature regimes than in a climate-controlled laboratory. Overall, endosulfan displayed the highest toxicity to tadpoles, although chlorothalonil was also highly toxic. The median lethal concentration estimated to kill 50% of a tested population (LC50) for endosulfan treatments under ambient temperatures was less than one-half of that for laboratory treatments (3.26 µg/L and 8.39 µg/L, respectively). Studies commonly performed in stable temperature-controlled laboratories may significantly underestimate toxicity compared with more realistic environmental regimes. Furthermore, global climatic changes are leading to warmer and more variable climates and may increase impacts of pesticides on amphibians. Environ Toxicol Chem 2013;32:2379–2386. © 2013 SETAC
Critical issues in using the common mixture toxicity models concentration addition or response addition on species sensitivity distributions: A theoretical approach
Authors: Gregorio Vincent , Chèvre Nathalie , Junghans Marion
Published: June 2013

The risk of chemical mixtures to ecosystems is often assessed by applying the model of concentration addition or response addition combined with species sensitivity distribution (SSD) curves. Mixture effect predictions have been shown to be consistent only when these models are applied for a single species, however, and not with several species simultaneously aggregated to SSDs. The more stringent procedure for mixture risk assessment would hence be to apply first the concentration addition or response addition models to each species separately and, in a second step, to combine the results to construct an SSD for a mixture. Unfortunately, this methodology is not applicable in most cases because the large data sets it requires are usually unavailable. Based on theoretical data sets generated, the authors aimed to characterize the difference that can exist between these 2 methodologies. Results show that the use of concentration addition on SSD directly may lead to underestimations of the mixture concentration affecting 5% or 50% of species, especially when substances present a large standard deviation in ecotoxicity data constructing their SSD. The application of response addition can lead to over- or underestimations, depending mainly on the slope of the dose–response curves of the individual species. When assessing the risk of mixtures, one must therefore keep in mind this source of error when applying concentration addition or response addition to SSDs directly. Environ Toxicol Chem 2013;32:2387–2395. © 2013 SETAC
The identity of the British Ordovician cystoid ‘Hemicosmites rugatus Forbes‘
Authors: Lanc Fiona A. , McDermott Patrick D. , Paul Christopher R. C.
Published: June 2013

New articulated specimens of the British Ordovician cystoid first mentioned under the name ‘Hemicosmites rugatus Forbes’ in 1848 allow its morphology and systematic affinities to be established for the first time. Despite being based on isolated plates, ‘H. rugatus Forbes’ has been reported from England and Wales, Belgium, France, Spain and Thailand, and has been attributed to four genera. It is characterized by a heteromorphic, circular stem, a theca with four basal, six infra‐lateral and eight lateral plates, all with sharp‐crested ridges running to plate angles, multiple arms in each ambulacrum and an extensive tegmen. These characters indicate it belongs in the family Caryocrinitidae and genus Caryocrinites. Caryocrinites rugatus had arms with lateral brachioles that folded in against the main arm axis, as in the type species C. ornatus Say. It is the first Ordovician species known to possess this character. Isolated plates show sorting and a few may represent other species of Caryocrinites s.l. Copyright © 2013 John Wiley & Sons, Ltd.
How much does it hurt to be lonely? Mental and physical differences between older men and women in the KORA‐Age Study
Authors: Zebhauser A. , Hofmann‐Xu L. , Baumert J. , Häfner S. , Lacruz M. E. , Emeny R. T. , Döring A. , Grill E. , Huber D. , Peters A. , Ladwig K. H.
Published: June 2013

Objective

Loneliness has a deep impact on quality of life in older people. Findings on sex‐specific differences on the experience of loneliness remain sparse. This study compared the intensity of and factors associated with loneliness between men and women.

Methods

Analyses are based on the 2008/2009 data of the KORA‐Age Study, comprising 4127 participants in the age range of 64–94 years. An age‐stratified random subsample of 1079 subjects participated in a face‐to‐face interview. Loneliness was measured by using a short German version of the UCLA‐Loneliness‐Scale (12 items, Likert scaled, ranging from 0 to 36 points). Multiple logistic regression analysis was conducted to analyze the associations of socio‐demographic, physical, and psychological factors with loneliness.

Results

The mean level of loneliness did not significantly differ between men (17.0 ± 4.5) and women (17.5 ± 5.1). However, among the oldest old (≥85 years), loneliness was higher in women (p value = 0.047). Depression, low satisfaction with life, and low resilience were associated significantly with loneliness, which was more pronounced in men. Living alone was not associated with loneliness, whereas lower social network was associated with a three time higher risk for feeling lonely in both men and women.

Conclusions

The extent of loneliness was equally distributed between men and women, although women were more disadvantaged regarding living arrangements as well as physical and mental health. However, loneliness was stronger associated with adverse mental health conditions in men. These findings should be considered when developing intervention strategies to reduce loneliness. Copyright © 2013 John Wiley & Sons, Ltd.
Minimalist model of ice microphysics in mixed‐phase stratiform clouds
Authors: Yang Fan , Ovchinnikov Mikhail , Shaw Raymond A.
Published: June 2013

The question of whether persistent ice crystal precipitation from supercooled layer clouds can be explained by time‐dependent, stochastic ice nucleation is explored using an approximate, analytical model and a large‐eddy simulation (LES) cloud model. The updraft velocity in the cloud defines an accumulation zone, where small ice particles cannot fall out until they are large enough, which will increase the residence time of ice particles in the cloud. Ice particles reach a quasi‐steady state between growth by vapor deposition and fall speed at cloud base. The analytical model predicts that ice water content (wi) has a 2.5 power‐law relationship with ice number concentration (ni). wi and ni from a LES cloud model with stochastic ice nucleation confirm the 2.5 power‐law relationship, and initial indications of the scaling law are observed in data from the Indirect and Semi‐Direct Aerosol Campaign. The prefactor of the power law is proportional to the ice nucleation rate and therefore provides a quantitative link to observations of ice microphysical properties.
Modeling the 2012 Wharton basin earthquakes off‐Sumatra: Complete lithospheric failure
Authors: Wei Shengji , Helmberger Don , Avouac Jean‐Philippe
Published: June 2013

A sequence of large strike‐slip earthquakes occurred west of Sunda Trench beneath the Wharton Basin. First reports indicate that the main shock was extremely complex, involving three to four subevents (Mw > 8) with a maze of aftershocks. We investigate slip models of the two largest earthquakes by joint inversion of regional and teleseismic waveform data. Using the Mw7.2 foreshock, we developed hybrid Green's Functions for the regional stations to approximate the mixture of oceanic and continental paths. The main shock fault geometry is defined based on the back projection results, point‐source mechanisms, aftershock distribution, and fine tune of grid searches. The fault system contains three faults, labeled F1 (89°/289° for dip/strike), F2 (74°/20°), and F3 (60°/310°). The inversion indicates that the main rupture consisted of a cascade of high‐stress drop asperities (up to 30 MPa), extending as deep as 50 km. The rupture propagated smoothly from one fault to the next (F1, F2, and F3 in sequence) with rupture velocities of 2.0–2.5 km/s. The whole process lasted about 200 s, and the major moment release (>70%) took place on the N‐S oriented F2. The Mw8.2 aftershock happened about 2 h later on a N‐S oriented fault with a relatively short duration (~60 s) and also ruptured as deep as 50 km. The slip distributions suggest that the earthquake sequence was part of a broad left‐lateral shear zone between the Australian and Indian plates and ruptured the whole lithosphere. These earthquakes apparently reactivated existing fracture zones and were probably triggered by unclamping of the great Sumatran earthquake of 2004.
Large‐scale influences on secondary eyewall size
Authors: Zhou Xiaqiong , Wang Bin
Published: June 2013

Secondary eyewalls are frequently observed in intense tropical cyclones (TCs). The separation distance between the primary eyewall and the secondary eyewall can vary from 10 to more than 100 km. The size of the secondary eyewall is a key factor determining the horizontal scale of the destructive winds and heavy rainfall in these TCs. Previous work suggested that the internal dynamic and thermodynamic structure of the TC affects the radial location of secondary eyewall formation. The potential impact of the large‐scale environment is examined by using the National Centers for Environmental Prediction‐National Center for Atmospheric Research reanalysis and best track data sets in this study. It is found that large secondary eyewalls tend to form in weak storms at relatively high latitudes and in environments with high relative humidity, low sea‐level pressure, and high low‐level vorticity. The performance of a statistical‐dynamical model to predict the size of secondary eyewalls is evaluated, and the physical interpretation of the selected predictors is also provided.
Inferring the uncertainty of satellite precipitation estimates in data‐sparse regions over land
Authors: Bytheway Janice L. , Kummerow Christian D.
Published: June 2013

The global distribution of precipitation is essential to understanding earth's water and energy budgets. While developed countries often have reliable precipitation observation networks, our understanding of the distribution of precipitation in data‐sparse regions relies on sporadic rain gauges and information gathered by spaceborne sensors. Several multisensor data sets attempt to represent the global distribution of precipitation on subdaily time scales by combining multiple satellite and ground‐based observations. Due to limited validation sources and highly variable nature of precipitation, it is difficult to assess the performance of multisensor precipitation products globally. Here, we introduce a methodology to infer the uncertainty of satellite precipitation measurements globally based on similarities between precipitation characteristics in data‐sparse and data‐rich regions. Five generalized global rainfall regimes are determined based on the probability distribution of 3‐hourly accumulated rainfall in 0.25° grid boxes using the Tropical Rainfall Measurement Mission 3B42 product. Uncertainty characteristics for each regime are determined over the United States using the high‐quality National Centers for Environmental Prediction Stage IV radar product. The results indicate that the frequency of occurrence of zero and little accumulated rainfall is the key difference between the regimes and that differences in error characteristics are most prevalent at accumulations below ~4 mm/h. At higher accumulations, uncertainty in 3‐hourly accumulation converges to ~80%. Using the self‐similarity in the five rainfall regimes along with the error characteristics observed for each regime, the uncertainty in 3‐hourly precipitation estimates can be inferred in regions that lack quality ground validation sources.
Embryological staging of the Zebra Finch,Taeniopygia guttata
Authors: Murray Jessica R. , Varian‐Ramos Claire W. , Welch Zoe S. , Saha Margaret S.
Published: June 2013

Zebra Finches (Taeniopygia guttata) are the most commonly used laboratory songbird species, yet their embryological development has been poorly characterized. Most studies to date apply Hamburger and Hamilton stages derived from chicken development; however, significant differences in development between precocial and altricial species suggest that they may not be directly comparable. We provide the first detailed description of embryological development in the Zebra Finch under standard artificial incubation. These descriptions confirm that some of the features used to classify chicken embryos into stages are not applicable in an altricial bird such as the Zebra Finch. This staging protocol will help to standardize future studies of embryological development in the Zebra Finch. J. Morphol. 274:1090–1110, 2013. © 2013 The Authors. Journal of Morphology Published by Wiley Periodicals, Inc.
Mass spectrometric studies on the in vitro generated metabolites of SIRT1 activating drugs for doping control purposes
Authors: Höppner Sebastian , Schänzer Wilhelm , Thevis Mario
Published: June 2013

The enzyme SIRT1 is a metabolic key regulator in mitochondrial biogenesis, fat and glucose metabolism. Its activation through pharmaceutical SIRT1 activators such as SRT2104 results in an increased deacetylation of substrates representing important targets for the treatment of metabolic diseases. Moreover, SRT1720 was found to enhance the physical performance of mice. As SIRT1 activators might therefore be relevant in a doping control context, metabolism studies of target substances need be conducted in order to develop a detection assay for SIRT1 activators in urine. In the present study, the in vitro metabolism of five SIRT1 activators was investigated using human liver microsomes. The mass spectrometric behavior of the resulting metabolites following positive electrospray ionization and collision‐induced dissociation was elucidated by high‐resolution/high‐accuracy (tandem) mass spectrometry, and confirmation of the structure of a major metabolite of SRT1720 was accomplished by chemical synthesis. Subsequently, a screening procedure for urine samples was developed employing liquid–liquid‐extraction and liquid chromatography/tandem mass spectrometry based on diagnostic ion transitions recorded in multiple reaction monitoring mode and the use of d8‐SRT1720 as deuterated internal standard. The method was validated with regard to specificity, sensitivity (limit of detection 0.5 ng/ml), recovery (88–99%) and imprecision (7–18%) as well as ion suppression/enhancement effects (<10%), demonstrating its fitness‐for‐purpose for sports drug testing applications. Copyright © 2013 John Wiley & Sons, Ltd.
Transfusion of older red blood cells is associated with decreased graft survival after orthotopic liver transplantation
Authors: Cywinski Jacek B. , You Jing , Argalious Maged , Irefin Samuel , Parker Brian M. , Fung John J. , Koch Colleen G.
Published: June 2013

Investigations have demonstrated conflicting results regarding the influence of the red blood cell (RBC) storage duration on outcomes. We evaluated whether graft failure or mortality after orthotopic liver transplantation (OLT) increased when recipients were transfused with older RBCs. This study included 637 patients who underwent OLT between January 2001 and June 2011. Baseline and perioperative data were obtained from our blood bank, the Unified Transplant Center database, and the United Network for Organ Sharing database. Recipients whose transfused RBCs were all stored for ≤15 days were grouped in a younger group, and recipients who were transfused with RBCs stored for >15 days were placed in an older group. The relationship between graft survival/mortality and the age of intraoperatively transfused RBCs was studied by Kaplan-Meier estimation with a log-rank test and multivariate Cox proportional hazards regression. Three hundred thirty-four patients and 303 patients were grouped in the younger and the older RBC groups, respectively, on the basis of the ages of intraoperatively transfused RBCs. Kaplan-Meier estimates of graft survival/mortality as a function of the posttransplant time were significantly different: the older group experienced the outcome sooner than the younger group [P = 0.02 (log-rank test)]. After covariate adjustments, the risk of graft failure/mortality was significantly different at any given time after transplantation between patients receiving intraoperative transfusions of older RBC units and patients receiving intraoperative transfusions of younger RBC units (hazard ratio = 1.65, 95% confidence interval = 1.18-2.31). In conclusion, patients who received intraoperative transfusions of RBCs with longer storage times had an increased risk of adverse outcomes. Liver Transpl 19:1181–1188, 2013. © 2013 AASLD.
Compliance with Corporate Policy: An Economic Approach
Authors: Blair Roger D. , Knight Thomas
Published: June 2013

We consider how corporations respond to public policy mandates with internal compliance policies and enforcement. We suppose that corporate compliance is determined by employees of the firm, whose incentives do not align perfectly with those of the corporation. In response, corporations expend resources to make compliance more likely. They adopt internal compliance policies and enforce these policies by sanctioning employees that violate them. Perfect compliance is unlikely, given imperfect observability of employee behavior. We present a number of laws and regulations with which firms may choose to comply, construct a model of internal compliance, and close with a discussion of different internal compliance policies and their feasibility. Copyright © 2013 John Wiley & Sons, Ltd.
Miniversal deformations of observable marked matrices
Authors: Compta Albert , Ferrer Josep , Peña Marta
Published: June 2013

Given the set of vertical pairs of matrices keeping the subspace invariant, we compute miniversal deformations of a given pair when it is observable, and the subspace is marked. Moreover, we obtain the dimension of the orbit, characterize the structurally stable vertical pairs, and study the effect of each deformation parameter. Copyright © 2013 John Wiley & Sons, Ltd.
A Compact Asymmetric Coplanar Strip‐Fed Dual‐Band Antenna for 2.4/5.8 GHz Wlan Applications
Authors: Li Yingsong , Li Wenxing , Ye Qiubo
Published: June 2013

An asymmetric coplanar strip (ACS)‐fed dual‐band antenna using loaded capacitance terminations for 2.4/5.8 GHz wireless local area network applications is studied numerically and verified experimentally. The proposed antenna consists of two meandered strip radiating elements, two loaded capacitance terminations, an asymmetric ground plane, a shunt inductor, and an ACS‐fed structure. Two resonance frequencies are controlled by adjusting the dimensions of the two meandered strip radiator elements and two loaded capacitance terminations. This antenna has small size of 17 × 12 mm2 including the ground plane. Simulation and measurement results show that the proposed antenna can work at dual‐band frequencies and has omnidirectional radiation patterns. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2066–2070, 2013
Distance Dependence of Electric Field Pattern for An Antenna Mounted on A Car in Uhf Band
Authors: Taguchi Kenji , Imai Suguru , Kashiwa Tatsuya , Kuribayashi Hiroshi , Komatsu Satoru
Published: June 2013

It is important to know distance dependence of electric field pattern to measure radiation patterns for car mounted antennas. In this article, the distance dependence of electric field pattern for an antenna mounted on a car in the UHF band is investigated by the electromagnetic simulation for the first time. As a result, it is shown that the distance dependence of electric field pattern is affected by polarization, frequency, antenna positions, and origin positions to define the distance. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2182–2186, 2013
Compact and High‐Selectivity Dual‐Band Bandpass Filter with Tunable Passband for Wimax and Wlan Applications
Authors: Li Yang , Wang C. , Kim N. Y.
Published: June 2013

A dual‐band bandpass filter with compact size and high‐selective performance is presented using the combination of an embedded double E‐type stepped‐impedance resonator and open‐loop resonators. The proposed dual‐band filter has the capability to achieve different passband frequencies, both resonance frequencies can be conveniently and independently controlled without enlarging outline circuit size, and four transmission zeros near the edges of the passband are achieved to obtain a high‐level selectivity. A comparison of simulated and measured results verifies the design and shows that two central frequencies of the fabricated filter are located at the desired 2.5 GHz (WiMax application) and 5.4 GHz (WLAN application) with 3 dB fractional bandwidths of 14.0 and 10.3%, respectively. The measured return losses are higher than 20 dB, whereas insertion losses are less than 0.9 dB in each of the two passbands. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2106–2110, 2013
Multipoint Response Correction for Reduced‐Cost EM‐Simulation‐Driven Design of Antenna Structures
Authors: Koziel Slawomir , Leifsson Leifur
Published: June 2013

We present a simple technique for electromagnetic (EM) simulation–based design optimization of antenna structures. Our approach utilizes a low‐fidelity model of the antenna under design, implemented through coarse‐discretization EM simulations. The low‐fidelity model is aligned with the original, high‐fidelity one using multipoint response correction. As opposed to the simple additive response correction (referred to as output space mapping), the multipoint version introduced here exploits all high‐fidelity model data accumulated during the optimization process, which improves the generalization capability of the corrected model. As a result, an optimized antenna design can be obtained at a lower computational cost, which is demonstrated using two examples: a dielectric resonator antenna and an ultra‐wideband stripline monopole antenna. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2070–2074, 2013
A Hybrid Silicon Single‐Mode Laser with A Racetrack Ring and Periodic Slots
Authors: Zhang Yejin , Wang Hailing , Qu Hongwei , Zhang Siriguleng , Zheng Wanhua
Published: June 2013

In this letter, a novel III‐V/silicon hybrid single‐mode ring cavity laser is presented. The on‐chip racetrack ring electrically pumped laser does not rely on facet polishing and dicing to define the laser cavity. The mode selected mechanism is based on a racetrack resonator with periodic slots. The fabrication of the laser only needs standard photolithography in the whole technological process. The side mode suppression ratio of larger than 20 dB is obtained from experiment. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2141–2143, 2013
A Dual‐Resonant Metamaterial in Terahertz Regime
Authors: Guo Wanyi , He Lianxing , Sun Hao , Li Biao , Zhao Hongwei , Sun Xiaowei
Published: June 2013

The design, fabrication, and measurement of a dual‐band terahertz (THz) metamaterial based on gallium arsenide substrate are presented. The proposed subwavelength structure provides two distinct electrical resonances near 0.39 and 0.59 THz. Measured results obtained from the THz time‐domain spectroscopy show good agreement with the simulation results. Effective medium parameters show negative values of permittivity during two frequency bands of 0.38–0.44 THz and 0.59–0.64 THz. This metamaterial is expected to enhance the realization of broadband and multiband functional devices in THz regime. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2095–2099, 2013
Novel Design of Broadband Strip Lines Fed Patch Antenna for GNSS Application
Authors: Li Xi , Lin Yang , Qiong Chen
Published: June 2013

Novel design of stacked circularly polarized strip lines fed patch antenna has been proposed for global navigation satellite system in this article. The antenna has been designed to operate for the satellite navigation frequencies including GPS, global navigation satellite system, Galileo and Compass (1100—1600 MHz). Three normal Wilkinson power dividers are connected together acting as the feeding networks. As a result, the antenna has a 57.6% 10‐dB return loss bandwidth from 1.05 to 1.9 GHz and 42.9% 3‐dB axial ratio bandwidth from 1.1 to 1.7 GHz, respectively. Crossed slots are cut on the radiating patch to increase the antenna gain. The designed antenna in this article can acquire broad beam width and good axial ratio at low elevations. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2062–2066, 2013
Mode‐Switching Left‐Handed Standing Wave Voltage‐Controlled Oscillator
Authors: Jang Sheng‐Lyang , Lin Hsi‐Han , Hsue Ching‐Wen
Published: June 2013

This article proposes a mode‐switching dual‐band CMOS standing‐wave oscillator (SWO) implemented with a distributed left‐handed (LH) LC network and CMOS mode switches. The SWO consists of four units of LH LC resonator stacked in series, and the LC resonator is in shunt with a pair of cross‐coupled transistors to compensate the loss of LC resonator. A pair of MOSFET mode‐switches is used to switch on/off the frequency bands. In the fundamental mode, the SWO operates at the high‐frequency band. In harmonic mode, the oscillator provides low‐frequency band outputs. The dual‐band function exploits the multiple oscillation mode of the LH SWO. The proposed SWO has been implemented with the TSMC 0.18 μm 1P6M CMOS technology. It can generate differential signals in the high‐band frequency range of 7.18–7.55 GHz and in the low‐band frequency range of 4.5–4.64 GHz. The die area of the SWO is 0.991 × 0.815 mm2. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2074–2077, 2013
Ultra‐Wideband Filters with Transmission Zeros in the Passband
Authors: Zhou Jiafeng , Morris Kevin
Published: June 2013

Wideband microwave filters cover a wide band of continuous frequencies. In this paper, the design and implementation of an ultra‐wideband filter is firstly introduced. In real applications, there might be interference inside the passband of the filter, and it is usually necessary to suppress the interference to make most use of the available bandwidth. Traditionally this can be done either by cascading a bandstop filter to the wideband filter, or by designing multiband filters. To achieve compactness, it will be shown in this paper that it is possible to add an extra resonator weakly coupled to the filter. Without any other changes to the original filter, a transmission zero can be produced in the passband of the filter, while the performance of the filter at other frequencies is not significantly affected. This zero can be used to suppress any potential in‐band interferences. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2165–2168, 2013
Bandwidth‐Enhanced Metamaterial Absorber Using Electric Field–Driven Lc Resonator For Airborne Radar Applications
Authors: Bhattacharyya Somak , Ghosh Saptarshi , Srivastava Kumar Vaibhav
Published: June 2013

The aim of this article is to construct broadband ultra thin absorbers using metamaterials in microwave frequencies (C‐band) for lower band surveillance and air defense applications. The frequencies of absorptions have been brought closer by parametric optimization of electric field driven LC structures to give rise to a higher full width at half maxima (FWHM) bandwidth. The FWHM bandwidth of 0.42 GHz with 8.13% has been theoretically observed ranging from 4.94–5.36 GHz. The structure is fabricated and experimentally tested for the normal incidence of electromagnetic wave inside the anechoic chamber. The structure is also investigated for oblique incidence which shows that FWHM bandwidth is maintained upto 40°. The structure is also simulated for different angles of polarization where insignificant shift in frequency is noticed as well as FWHM bandwidth is also maintained upto 30°. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2131–2137, 2013
Accurate Backscattering Studies for Double‐Layered Array of Infinitely Long Cylinders
Authors: Safonova Galyna , Vinogradova Elena
Published: June 2013

The two‐dimensional Helmholtz equation with Dirichlet's boundary conditions is rigorously solved for multiple arbitrary profiled cylinders. This describes the wave diffraction of E‐polarized electromagnetic field. The developed algorithm is used for calculation of the radar cross‐section of an infinitely long double‐layered array. In this article, we focus on the resonance response of the structure caused by excitation of the high Q‐factor oscillations. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2127–2131, 2013
A 5‐GHz Band Low‐Phase Noise CMOS VCO Using Above‐IC Technologies
Authors: Chiou Hwann‐Kaeo , Hsu Yuan‐Chia , Chang Da‐Chiang , Juang Ying‐Zong
Published: June 2013

This article presents a 5‐GHz band low phase noise CMOS voltage controlled oscillator (VCO) based on a high quality factor above‐IC inductor that is stacked on the top of a 0.18‐μm RF CMOS process using wafer level package technology. The measured phase noise of the VCO is −119.8 dBc/Hz at 1 MHz offset frequency, which is an improvement of 6 dB compared to a conventional VCO with on‐chip CMOS inductor. The design challenge of the grounding of the above‐IC inductor stacked on the CMOS structure is investigated in this work. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2051–2055, 2013
Miniature Reconfigurable Antenna with Magneto Dielectric Substrate for DVB‐H Band
Authors: Canneva Florian , Ferrero Fabien , Chevalier Alexis , Ribero Jean‐Marc , Mattei Jean‐Luc , Queffelec Patrick , Staraj Robert
Published: June 2013

In this article, we present a frequency reconfigurable antenna for digital video broadcasting on handheld devices standard. By loading a printed inverted F antennas with a varactor diode, the resonance frequency can be tuned from 470 to 862 MHz. Furthermore, a magneto dielectric superstrate is used to reduce the dimension of the antenna while keeping a large bandwidth. To study the performance improvement due to the magneto‐dielectric resonator,a comparison is performed with a reference antenna without magneto‐dielectric superstrate. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2007–2011, 2013
Analysis of Different Loop Resonators and Their Application in Band‐Stop Filter Design
Authors: Shen Rui , Lin Xianqi , Zhang Pengcheng , Cheng Fei , Fan Yong
Published: June 2013

This article presents six typical loop resonators with single electric or magnetic resonance. Capacitive or inductive load leads to the invention of reflection zeros and the position of loaded gap or via results in different mutual coupling effects. After detailed study on the characteristics of such six typical loop resonator prototypes, a second‐order filter with a more compact size and high selectivity is proposed. Realization of spurious band suppression as well as miniaturization is investigated and achieved. Full wave simulation and necessary measurements are taken and good agreements are achieved. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2241–2244, 2013