bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors influencing learner satisfaction with team‐based learning among nursing students
Authors: Roh Young Sook , Lee Suk Jeong , Mennenga Heidi
Published: March 2014

In this study, learner satisfaction was described, and factors influencing satisfaction with team‐based learning were identified. This was a cross‐sectional, descriptive survey study. Two separate 2 h team‐based, learning sessions, consisting of preparation, readiness assurance, and application, were given to a cohort of 139 second year nursing students in 2010 and 263 students in 2011, respectively. At the end of the learning sessions, participants completed a self‐administered questionnaire regarding their learning experience. Nursing students were generally satisfied with team‐based learning. Multiple regression analysis revealed that the learning process significantly affected learner satisfaction compared to pre‐assignment, course content, peer evaluation, and team activity. According to these results, team‐based learning facilitators should organize and conduct team‐based learning activities, while also considering instructional design factors, to help students learn effectively.
Gender differences in the relationship between physical functioning and depressive symptoms in low‐income older adults living alone
Authors: Lim Eun Ju
Published: March 2014

This study examined gender differences in the relationship between physical functioning and depressive symptoms in low‐income older adults living alone in Korea, and the variables influencing these symptoms. Data from a total of 317 older adults in the 2011 Korean National Survey were used. Upper limb mobility, lower limb mobility, activities of daily living, instrumental activities of daily living, and depressive symptoms were measured. Data were analyzed using multiple regression analysis. Low‐income older men and women living alone experienced depressive symptoms. Regression analysis showed that lower limb mobility and age together explained 35.4% of the variance in depressive symptoms in men. Subjective health status explained 16.7% of the same in women. These findings suggest that low‐income older adults living alone should be carefully monitored by public healthcare managers to improve their physical and mental health, considering gender‐specific elements.
Korean hospice nursing interventions using the Nursing Interventions Classification system: A comparison with the USA
Authors: Hong Sung‐Jung , Lee Eunjoo
Published: March 2014

In this study, nursing interventions used by hospice nurses in Korea were identified and compared with core interventions selected by US end‐of‐life care nurses in order to determine similarities and differences between the two nations regarding such care. Data were collected from the electronic medical records of 353 hospice patients admitted to a tertiary hospital in Korea over a period of two years. First, extracted narrative interventions were mapped onto the Nursing Interventions Classification for comparison with interventions selected by nurses in the USA. A total of 56,712 intervention statements were mapped onto 147 Nursing Interventions Classification interventions. Hospice nurses in Korea performed more nursing interventions in the physiological basic domain, compared to nurses in the USA. The most frequently‐used interventions in Korea were related to patient pain management. Among 47 core Nursing Interventions Classification interventions used in the USA, only 18 were used by Korean nurses in this study. This study highlights cultural differences in hospice care nursing interventions between the two countries.
Israeli Arab Muslim women's willingness to be screened for intimate partner violence: A survey
Authors: Ben Natan Merav , Muasi Hiba , Farhan Fidaa , Shhada Miada , Masarwa Gada
Published: March 2014

In the present study, we explored whether the research model based on the Theory of Reasoned Action predicts Israeli Arab Muslim women's willingness to be screened for intimate partner violence at healthcare facilities. Three hundred women completed a questionnaire. Most women (68.4%) expressed willingness to be screened, however, only 16% of them had been screened over the past year. Women's beliefs about screening for intimate partner violence and the support of significant others were found to predict this willingness. The study may constitute an initial foundation for determining national policy with the aim of detecting and eradicating the phenomenon among this unique population.
Metallothionein deficiency impacts copper accumulation and redistribution in leaves and seeds of Arabidopsis
Authors: R. Benatti Matheus , Yookongkaew Nimnara , Meetam Metha , Guo Woei‐Jiun , Punyasuk Napassorn , AbuQamar Synan , Goldsbrough Peter
Published: March 2014

Most angiosperm genomes contain several genes encoding metallothionein (MT) proteins that can bind metals including copper (Cu) and zinc (Zn). Metallothionein genes are highly expressed under various conditions but there is limited information about their function. We have studied Arabidopsis mutants that are deficient in multiple MTs to learn about the functions of MTs in plants.

T‐DNA insertions were identified in four of the five Arabidopsis MT genes expressed in vegetative tissues. These were crossed to produce plants deficient in four MTs (mt1a/mt2a/mt2b/mt3).

The concentration of Cu was lower in seeds but higher in old leaves of the quad‐MT mutant compared to wild‐type plants. Experiments with stable isotopes showed that Cu in seeds came from two sources: directly from roots and via remobilization from other organs. Mobilization of Cu out of senescing leaves was disrupted in MT‐deficient plants. Tolerance to Cu, Zn and paraquat was unaffected by MT deficiency but these plants were slightly more sensitive to cadmium (Cd). The quad‐MT mutant showed no change in resistance to a number of microbial pathogens, or in the progression of leaf senescence.

Although these MTs are not required to complete the plant's life cycle, MTs are important for Cu homeostasis and distribution in Arabidopsis.
The root indeterminacy‐to‐determinacy developmental switch is operated through a folate‐dependent pathway in Arabidopsis thaliana
Authors: Reyes‐Hernández Blanca Jazmín , Srivastava Avinash C. , Ugartechea‐Chirino Yamel , Shishkova Svetlana , Ramos‐Parra Perla A. , Lira‐Ruan Verónica , Díaz de la Garza Rocío I. , Dong Gaofeng , Moon Jun‐Cheol , Blancaflor Elison B. , Dubrovsky Joseph G.
Published: March 2014

Roots have both indeterminate and determinate developmental programs. The latter is preceded by the former. It is not well understood how the indeterminacy‐to‐determinacy switch (IDS) is regulated.

We isolated a moots koom2 (mko2; ‘short root’ in Mayan) Arabidopsis thaliana mutant with determinate primary root growth and analyzed the root apical meristem (RAM) behavior using various marker lines. Deep sequencing and genetic and pharmacological complementation permitted the identification of a point mutation in the FOLYLPOLYGLUTAMATE SYNTHETASE1 (FPGS1) gene responsible for the mko2 phenotype.

Wild‐type FPGS1 is required to maintain the IDS in the ‘off’ state. When FPGS1 function is compromised, the IDS is turned on and the RAM becomes completely consumed. The polyglutamate‐dependent pathway of the IDS involves activation of the quiescent center independently of auxin gradients and regulatory modules participating in RAM maintenance (WUSCHEL‐RELATED HOMEOBOX5 (WOX5), PLETHORA, and SCARECROW (SCR)). The mko2 mutation causes drastic changes in folate metabolism and also affects lateral root primordium morphogenesis but not initiation.

We identified a metabolism‐dependent pathway involved in the IDS in roots. We suggest that the root IDS represents a specific developmental pathway that regulates RAM behaviour and is a different level of regulation in addition to RAM maintenance.
Le récit de soi : une mémoire au futur
Authors: Moioli Aurélie
Published: March 2014

Cet article met en évidence la tension prospective de la mémoire romantique en comparant deux récits autobiographiques – la Konjektural‐Biographie de Jean Paul (1799) et les Ultime lettere di Jacopo Ortis d'Ugo Foscolo (1817). Il montre que le récit de soi pointe vers l'avenir et vers le possible. À rebours du geste rétrospectif qui caractérise traditionnellement l'autobiographie, les œuvres originales de Jean Paul et d'Ugo Foscolo imaginent la vie à venir du je. Elles sont prospectives parce qu'elles relèvent de la « conjecture » et de l'anticipation, de la prophétie et de la promesse. Ce regard prospectif est lié à la présence de la mort qui hante l'autobiographe et le transforme en spectre. La figure du spectre, qui se trouve au croisement d'une réflexion sur le temps et sur l'imagination, permet d’éclairer le fonctionnement complexe de la mémoire – de la mémoire individuelle et collective. Le récit de soi est un espace spectral qui disjoint le temps et qui cependant contient les germes du futur. Cette tension vers l'avenir a un sens éminemment politique et éthique pour Jean Paul et Ugo Foscolo qui écrivent ces vies conjecturales au sortir des révolutions et en réaction aux violences de l'Histoire.
Origins and early evolution of arthropods
Authors: Edgecombe Gregory D. , Legg David A.
Published: March 2014

Phylogenomics reconstructs an arthropod tree in which a monophyletic Arthropoda splits into Pycnogonida + Euchelicerata and Myriapoda + Pancrustacea. The same chelicerate–mandibulate groups are retrieved with morphological data sets, including those encompassing most taxa known from Palaeozoic Konservat‐Lagerstätten. With respect to the interrelationships of the three extant clades of Panarthropoda, a sister group relationship between Onychophora and Arthropoda is endorsed by transcriptomics and microRNAs, although this hypothesis forces homoplasy in characters of the segmental ganglia that are shared by tardigrades and arthropods. Cambrian lobopodians, dinocaridids, bivalved arthropods and fuxianhuiids document the successive appearance of characteristic arthropod features in the stem lineage of Euarthropoda (crown‐group arthropods). Molecular dating suggests that arthropods had their origin and initial diversification in the Ediacaran, but no convincing palaeontological evidence for Panarthropoda is available until the earliest Cambrian.
Nectar secretion dynamic links pollinator behavior to consequences for plant reproductive success in the ornithophilous mistletoe Psittacanthus robustus
Authors: Guerra T. J. , Galetto L. , Silva W. R.
Published: March 2014

The mistletoe Psittacanthus robustus was studied as a model to link flower phenology and nectar secretion strategy to pollinator behaviour and the reproductive consequences for the plant. The bright‐coloured flowers presented diurnal anthesis, opened asynchronously throughout the rainy season and produced copious dilute nectar as the main reward for pollinators. Most nectar was secreted just after flower opening, with little sugar replenishment after experimental removals. During the second day of anthesis in bagged flowers, the flowers quickly reabsorbed the offered nectar. Low values of nectar standing crop recorded in open flowers can be linked with high visitation rates by bird pollinators. Eight hummingbirds and two passerines were observed as potential pollinators. The most frequent flower visitors were the hummingbirds Eupetomena macroura and Colibri serrirostris, which actively defended flowering mistletoes. The spatial separation between anthers, stigma and nectar chamber promotes pollen deposition on flapping wings of hovering hummingbirds that usually probe many flowers per visit. Seed set did not differ between hand‐, self‐ and cross‐pollinated flowers, but these treatments set significantly more seeds than flowers naturally exposed to flower visitors. We suggest that the limitation observed in the reproductive success of this plant is not related to pollinator scarcity, but probably to the extreme frequency of visitation by territorial hummingbirds. We conclude that the costs and benefits of plant reproduction depend on the interaction strength between flowers and pollinators, and the assessment of nectar secretion dynamics, pollinator behaviour and plant breeding system allows clarification of the complexity of such associations.
Physical Attractiveness and Social Status
Authors: Frevert Tonya K. , Walker Lisa Slattery
Published: March 2014

In this article, we outline the evidence regarding the status effects of physical attractiveness, paying particular attention to outcomes in the areas of jobs, crime, performance evaluations, power, health perceptions, and exchange. The framework of status characteristics theory is used to guide our explication. The role of attractiveness in marketing is also discussed. While the literature generally supports the idea that attractiveness is good for people, we also consider evidence that beauty can be detrimental for some individuals in certain situations. Issues of race and gender are also considered as well as future research directions.
Hybrid Masculinities: New Directions in the Sociology of Men and Masculinities
Authors: Bridges Tristan , Pascoe C. J.
Published: March 2014

Hybrid masculinity refers to men's selective incorporation of performances and identity elements associated with marginalized and subordinated masculinities and femininities. We use recent theorization of hybrid masculinities to critically review theory and research that seeks to make sense of contemporary transformations in masculinity. We suggest that research broadly supports three distinct consequences associated with recent changes in performances and politics of masculinity that work to obscure the tenacity of gendered inequality. Hybrid masculinities (i) symbolically distance men from hegemonic masculinity; (ii) situate the masculinities available to young, White, heterosexual men as somehow less meaningful than the masculinities associated with various marginalized and subordinated Others; and (iii) fortify existing social and symbolic boundaries in ways that often work to conceal systems of power and inequality in historically new ways.
Drug Use Among Latino Youth: Two Popular Criminological Perspectives Infused with Latino Culture
Authors: Kopak Albert M.
Published: March 2014

Drug use among Latino youth in the United States is a persistent problem which has been examined from a variety of academic disciplines, including psychology, sociology, and social work. These share significant overlap with mainstream criminological approaches to explaining delinquency and drug use, which have virtually ignored these issues or investigated them exclusively from an ethnocentric perspective. The naturally multidisciplinary topics of Latino youth, culture, and drug use can be readily situated within two popular frameworks (social control and strain), and these can also be enriched with core aspects of Latino culture. Complimentary cultural values enhance these two perspectives and significantly contribute to our criminological understanding of some of the reasons why Latino youth become involved in drug use. After reviewing our current knowledge on this subject, suggestions are made for ways future criminological research can more deeply explore these rich cultural reasons related to why some Latino youth use drugs. This can ultimately help inform more relevant drug use reduction strategies and also decrease the proportion of Latino youth who come into contact with the criminal justice system for drug‐related offenses.
Microparticle profile and procoagulant activity of fresh‐frozen plasma is affected by whole blood leukoreduction rather than 24‐hour room temperature hold
Authors: Chan Kasey Sze‐Kei , Sparrow Rosemary L.
Published: March 2014

Background

Microparticles (MPs) are small phospholipid‐containing vesicles that have procoagulant properties. MPs are thought to contribute to the hemostatic potential of plasma. This study investigated the effects of whole blood (WB) hold time and leukoreduction (LR) on the MP profile and hemostatic potential of fresh‐frozen plasma (FFP).

Study Design and Methods

WB units (n = 12) from healthy donors were divided into two pairs and each pair was held at 20 to 24°C for 6 or 24 hours. At the designated hold time, 1 unit from the pair was LR while the other unit was not LR. FFP was prepared by standard procedures, aliquoted, and frozen. The MP content was determined by flow cytometry using an absolute count assay and specific labels for red blood cells (CD235a), platelets (CD41), and phosphatidylserine (PS). The hemostatic potential was determined by thrombelastography (TEG) and coagulation factor assays.

Results

Compared to non‐LR‐FFP, LR‐FFP had significantly lower numbers of MPs, particularly CD41+ MPs and PS‐positive MPs (p < 0.03). LR‐FFP, compared to non‐LR‐FFP, had a slower clot formation time (p = 0.002); lower clot strength (p < 0.001); and lower Factor (F)VIII, FXII, and fibrinogen levels (p < 0.01). With longer WB hold time, the TEG profile was unchanged, although FVIII levels were decreased as expected (p < 0.01). On average FFP units met quality requirements.

Conclusion

LR of WB resulted in lower hemostatic potential of FFP in conjunction with depletion of MPs and coagulation factors. Longer WB hold time did not significantly affect the hemostatic potential of FFP as measured by TEG. Acceptable hemostatic quality was maintained for all FFP processing conditions studied.
Histamine inhibits the melanin‐concentrating hormone system: implications for sleep and arousal
Authors: Parks Gregory S. , Olivas Nicholas D. , Ikrar Taruna , Sanathara Nayna M. , Wang Lien , Wang Zhiwei , Civelli Olivier , Xu Xiangmin
Published: March 2014

Key points

Melanin‐concentrating hormone (MCH) neurons express histamine‐3 receptor (H3R) mRNA but not histamine‐1 (H1R) or histamine‐2 (H2R) receptor mRNA.

Histamine inhibits MCH neurons by activating postsynaptic H3R. This effect is mediated through G protein‐dependent inwardly rectifying potassium (GIRK) channels.

Histamine may function to silence MCH neurons during wakefulness.

Melanin‐concentrating hormone (MCH)‐producing neurons are known to regulate a wide variety of physiological functions such as feeding, metabolism, anxiety and depression, and reward. Recent studies have revealed that MCH neurons receive projections from several wake‐promoting brain regions and are integral to the regulation of rapid eye movement (REM) sleep. Here, we provide evidence in both rats and mice that MCH neurons express histamine‐3 receptors (H3R), but not histamine‐1 (H1R) or histamine‐2 (H2R) receptors. Electrophysiological recordings in brain slices from a novel line of transgenic mice that specifically express the reporter ZsGreen in MCH neurons show that histamine strongly inhibits MCH neurons, an effect which is TTX insensitive, and blocked by the intracellular presence of GDP‐β‐S. A specific H3R agonist, α‐methylhistamine, mimicks the inhibitory effects of histamine, and a specific neutral H3R antagonist, VUF 5681, blocks this effect. Tertiapin Q (TPQ), a G protein‐dependent inwardly rectifying potassium (GIRK) channel inhibitor, abolishes histaminergic inhibition of MCH neurons. These results indicate that histamine directly inhibits MCH neurons through H3R by activating GIRK channels and suggest that that inhibition of the MCH system by wake‐active histaminergic neurons may be responsible for silencing MCH neurons during wakefulness and thus may be directly involved in the regulation of sleep and arousal.
Modulating effect of SIRT1 activation induced by resveratrol on Foxo1‐associated apoptotic signalling in senescent heart
Authors: Sin Thomas K. , Yu Angus P. , Yung Benjamin Y. , Yip Shea Ping , Chan Lawrence W. , Wong Cesar S. , Ying Michael , Rudd John A. , Siu Parco M.
Published: March 2014

Key points

Cardiac function is impaired and Foxo1/Bim‐related apoptotic signalling is up‐regulated in senescent heart

Activation of SIRT1 deacetylase activity by resveratrol attenuates the Foxo1/Bim signalling axis in senescent heart

Elevations of cardiomyocyte apoptosis and fibrotic deposition are major characteristics of the ageing heart. Resveratrol, a polyphenol in grapes and red wine, is known to improve insulin resistance and increase mitochondrial biogenesis through the SIRT1–PGC‐1α signalling axis. Recent studies attempted to relate SIRT1 activation by resveratrol to the regulation of apoptosis in various disease models of cardiac muscle. In the present study, we tested the hypothesis that long‐term (8‐month) treatment of resveratrol would activate SIRT1 and improve the cardiac function of senescent mice through suppression of Foxo1‐associated pro‐apoptotic signalling. Our echocardiographic measurements indicated that the cardiac systolic function measured as fractional shortening and ejection fraction was significantly reduced in aged mice when compared with the young mice. These reductions, however, were not observed in resveratrol‐treated hearts. Ageing significantly reduced the deacetylase activity, but not the protein abundance of SIRT1 in the heart. This reduction was accompanied by increased acetylation of the Foxo1 transcription factor and transactivation of its target, pro‐apoptotic Bim. Subsequent analyses indicated that pro‐apoptotic signalling measured as p53, Bax and apoptotic DNA fragmentation was up‐regulated in the heart of aged mice. In contrast, resveratrol restored SIRT1 activity and suppressed elevations of Foxo1 acetylation, Bim and pro‐apoptotic signalling in the aged heart. In parallel, resveratrol also attenuated the ageing‐induced elevations of fibrotic collagen deposition and markers of oxidative damage including 4HNE and nitrotyrosine. In conclusion, these novel data demonstrate that resveratrol mitigates pro‐apoptotic signalling in senescent heart through a deacetylation mechanism of SIRT1 that represses the Foxo1–Bim‐associated pro‐apoptotic signalling axis.
Ponto‐medullary nuclei involved in the generation of sequential pharyngeal swallowing and concomitant protective laryngeal adduction in situ
Authors: Bautista Tara G. , Dutschmann Mathias
Published: March 2014

Key points

Laryngeal adduction is a major mechanism in sealing off entry to the trachea to prevent aspiration during swallowing.

An experimental protocol to reliably elicit sequential swallowing by oral injection of small volumes of water was developed in the in situ perfused brainstem preparation of juvenile rats.

The sequential swallowing motor pattern consists of two distinct components: (i) phasic swallowing, indicated by rhythmic sequential vagal nerve bursting, and (ii) protective laryngeal adduction, indicated by background tonic vagal discharge.

Pharmacological manipulation of the Kölliker–Fuse nucleus revealed that it specifically mediates the protective tonic laryngeal adduction, while GABAergic neurotransmission is needed in the nucleus of the solitary tract for the generation of the sequential swallowing motor pattern.

We conclude that sequential swallow motor patterning, including effective airway protection, requires balanced excitatory–inhibitory synaptic interaction within the nucleus of the solitary tract and the Kölliker–Fuse nucleus, as well as between the two nuclei.

Both swallowing and respiration involve postinspiratory laryngeal adduction. Swallowing‐related postinspiratory neurons are likely to be located in the nucleus of the solitary tract (NTS) and those involved in respiration are found in the Kölliker–Fuse nucleus (KF). The function of KF and NTS in the generation of swallowing and its coordination with respiration was investigated in perfused brainstem preparations of juvenile rats (n = 41). Orally injected water evoked sequential pharyngeal swallowing (s‐PSW) seen as phasic, spindle‐shaped bursting of vagal nerve activity (VNA) against tonic postinspiratory discharge. KF inhibition by microinjecting isoguvacine (GABAA receptor agonist) selectively attenuated tonic postinspiratory VNA (n = 10, P < 0.001) but had no effect on frequency or timing of s‐PSW. KF disinhibition after bicuculline (GABAA receptor antagonist) microinjections caused an increase of the tonic VNA (n = 8, P < 0.01) resulting in obscured and delayed phasic s‐PSW. Occurrence of spontaneous PSW significantly increased after KF inhibition (P < 0.0001) but not after KF disinhibition (P = 0.14). NTS isoguvacine microinjections attenuated the occurrence of all PSW (n = 5, P < 0.01). NTS bicuculline microinjections (n = 6) resulted in spontaneous activation of a disordered PSW pattern and long‐lasting suppression of respiratory activity. Pharmacological manipulation of either KF or NTS also triggered profound changes in respiratory postinspiratory VNA. Our results indicate that the s‐PSW comprises two functionally distinct components. While the primary s‐PSW is generated within the NTS, a KF‐mediated laryngeal adductor reflex safeguards the lower airways from aspiration. Synaptic interaction between KF and NTS is required for s‐PSW coordination with respiration as well as for proper gating and timing of s‐PSW.
Analysis of Expansion Joints Movement Test in FCC Unit
Authors: Veiga Jordana L. B. C. , Medeiros Jorivaldo , Carlos Veiga José
Published: March 2014

The turboexpander is an equipment that works under very critical conditions requiring very low allowable nozzle forces and moments. A solution to minimize the piping loads transmitted to the equipment is the use of expansion joints (EJ). A usual piping stress analysis normally is not enough to guarantee the turboexpander reliability. This paper shows the results obtained in a movement test realized on metallic bellows EJ used in a turboexpander piping system. The EJ were designed according to the expansion joints manufacturer association code (EJMA), the diameters range from 0.457 to 2,898 m, the material of the bellows is Inconel 625 LCF and the shell materials are “killed” carbon steel, for refractory lined EJ or stainless steel 304H. A special test device was developed to apply the design movements on the EJ at the factory. A digital dynamometer was used for data acquisition and the tests were performed on 16 EJ of two distinct types: hinged and gimbal. The EJ were pressurized with water during the test. The reactions and corresponding displacements for each step of the test were recorded during loading and unloading.
Dislocation Density-Based Grain Refinement Modeling of Orthogonal Cutting of Titanium
Authors: Ding Hongtao , Shin Yung C.
Published: March 2014

Recently, orthogonal cutting has been exploited as a means for producing ultrafine grained (UFG) and nanocrystalline microstructures for various metal materials, such as aluminum alloys, copper, stainless steel, titanium and nickel-based super alloys, etc. However, no predictive, analytical or numerical work has ever been presented to quantitatively predict the change of grain sizes during plane-strain orthogonal cutting. In this paper, a dislocation density-based material plasticity model is adapted for modeling the grain size refinement mechanism during orthogonal cutting by means of a finite element based numerical framework. A coupled Eulerian–Lagrangian (CEL) finite element model embedded with the dislocation density subroutine is developed to model the severe plastic deformation and grain refinement during a steady-state cutting process. The orthogonal cutting tests of a commercially pure titanium (CP Ti) material are simulated in order to assess the validity of the numerical solution through comparison with experiments. The dislocation density-based material plasticity model is calibrated to reproduce the observed material constitutive mechanical behavior of CP Ti under various strains, strain rates, and temperatures in the cutting process. It is shown that the developed model captures the essential features of the material mechanical behavior and predicts a grain size of 100–160 nm in the chips of CP Ti at a cutting speed of 10 mm/s.
Operational Shock Failure Mechanisms in Hard Disk Drives
Authors: Li Liping , Bogy David B.
Published: March 2014

The work performance of a hard disk drive (HDD) in mobile devices depends very much on its ability to withstand external disturbances. In this study, a detailed multibody structural model integrated with a complete air bearing model is developed to investigate the disk drive's response during external shocks. The head disk interface (HDI) failure mechanisms when the HDD is subjected to different shock cases are discussed. For a negative shock case in which the disk initially moves towards the head, with long pulse width, the air bearing becomes very stiff before the slider crashes on the disk, and the HDI fails only when the external load overcomes the air bearing force. For other shock cases, the slider contacts the disk due to a negative net bearing force caused by the slider-disk separation. Finally, a stiffer suspension design is proposed to improve the drive shock performance, especially during a positive shock, as under these conditions, the slider contacts the disk primarily due to the stiffness difference of the different drive components.
Multiple-Model Sensor and Components Fault Diagnosis in Gas Turbine Engines Using Autoassociative Neural Networks
Authors: Sadough Vanini Z. N. , Meskin N. , Khorasani K.
Published: March 2014

In this paper the problem of fault diagnosis in an aircraft jet engine is investigated by using an intelligent-based methodology. The proposed fault detection and isolation (FDI) scheme is based on the multiple model approach and utilizes autoassociative neural networks (AANNs). This methodology consists of a bank of AANNs and provides a novel integrated solution to the problem of both sensor and component fault detection and isolation even though possibly both engine and sensor faults may occur concurrently. Moreover, the proposed algorithm can be used for sensor data validation and correction as the first step for health monitoring of jet engines. We have also presented a comparison between our proposed approach and another commonly used neural network scheme known as dynamic neural networks to demonstrate the advantages and capabilities of our approach. Various simulations are carried out to demonstrate the performance capabilities of our proposed fault detection and isolation scheme.
On the Impact of Geometric Variability on Fan Aerodynamic Performance, Unsteady Blade Row Interaction, and Its Mechanical Characteristics
Authors: Schnell R. , Lengyel-Kampmann T. , Nicke E.
Published: March 2014

The focus of the present study is to assess and quantify the uncertainty in predicting the steady and unsteady aerodynamic performance as well as the major mechanical characteristics of a contrarotating turbofan, primarily due to geometric variations stemming from the manufacturing process. The basis of this study is the optically scanned blisk of the first rotor, for which geometric variations from blade to blade are considered. In a first step, selected profile sections of the first rotor were evaluated aerodynamically by applying the 2D coupled Euler/boundary-layer solver mises. Statistical properties of the relevant flow quantities were calculated firstly based on the results of the nine manufactured blades. In a second step, the geometric variations were decomposed into their corresponding eigenforms by means of principal component analysis (PCA). These modes were the basis for carrying out Monte Carlo (MC) simulations in order to analyze in detail the blade's aerodynamic response to the prescribed geometric variations. By means of 3D-computational fluid dynamics (CFD) simulations of the entire fan stage for all the nine scanned rotor 1 blade geometries, the variation of the overall stage performance parameters will be quantified. The impact of the instrumentation will be discussed, here partly doubling the standard deviation of the major performance indicators for the instrumented blades and also triggering a premature laminar/turbulent transition of the boundary layer. In terms of the unsteady blade row interaction, the standard deviation of the resulting blade pressure amplitude shall be discussed based on unsteady simulations, taking advantage of a novel harmonic balance approach. It will be shown that the major uncertainty in terms of the predicted blade pressure amplitude is in the aft part of the front rotor and results from upstream shock/blade interaction. Apart from the aerodynamic performance, an analysis of the mechanical properties in terms of Campbell characteristics and eigenfrequencies was carried out for each of the scanned blades of rotor 1, reflecting the frequency scattering of each eigenmode due to geometric variability.
Silicon photodetectors integrated with vertical silicon nitride waveguides as image sensor pixels: Fabrication and characterization
Authors: Tut Turgut , Dan Yaping , Duane Peter , Ye Winnie N. , Degirmenci Fatih , Yu Young , Wober Munib , Crozier Kenneth B.
Published: March 2014

The current trend toward image sensors with ever-increasing pixel counts is prompting continual reductions in pixel area, leading to significant cross-talk and efficiency challenges. The realization of image sensor pixels containing waveguides presents a means for addressing these issues. The fabrication of such pixels is however not straightforward. Conventional waveguides employed in integrated optics are horizontal, but waveguides needed for the proposed sensor must be vertical and integrated with photodetectors. Here, the authors describe a fabrication process for vertical silicon nitride waveguides integrated with silicon photodetectors. The authors describe the etching, deposition, and planarization techniques that enable the formation of silicon nitride waveguides embedded in silicon dioxide. They also describe a fabrication process for silicon photodetectors, including a means for ensuring that their photosensitive areas have sizes consistent with those of photodetectors employed in conventional image sensors. In addition, the authors perform optical and electrical characterization of the fabricated devices. The results demonstrate the ability of the fabricated waveguides to guide light onto the photodetectors with high efficiency.
Spatio‐temporal texture (SpTeT) for distinguishing vulnerable from stable atherosclerotic plaque on dynamic contrast enhancement (DCE) MRI in a rabbit model
Authors: Wan Tao , Madabhushi Anant , Phinikaridou Alkystis , Hamilton James A. , Hua Ning , Pham Tuan , Danagoulian Jovanna , Kleiman Ross , Buckler Andrew J.
Published: March 2014

Purpose:

To develop a new spatio‐temporal texture (SpTeT) based method for distinguishing vulnerable versus stable atherosclerotic plaques on DCE‐MRI using a rabbit model of atherothrombosis.

Methods:

Aortic atherosclerosis was induced in 20 New Zealand White rabbits by cholesterol diet and endothelial denudation. MRI was performed before (pretrigger) and after (posttrigger) inducing plaque disruption with Russellˈs‐viper‐venom and histamine. Of the 30 vascular targets (segments) under histology analysis, 16 contained thrombus (vulnerable) and 14 did not (stable). A total of 352 voxel‐wise computerized SpTeT features, including 192 Gabor, 36 Kirsch, 12 Sobel, 52 Haralick, and 60 first‐order textural features, were extracted on DCE‐MRI to capture subtle texture changes in the plaques over the course of contrast uptake. Different combinations of SpTeT feature sets, in which the features were ranked by a minimum‐redundancy‐maximum‐relevance feature selection technique, were evaluated via a random forest classifier. A 500 iterative 2‐fold cross validation was performed for discriminating the vulnerable atherosclerotic plaque and stable atherosclerotic plaque on per voxel basis. Four quantitative metrics were utilized to measure the classification results in separating between vulnerable and stable plaques.

Results:

The quantitative results show that the combination of five classes of SpTeT features can distinguish between vulnerable (disrupted plaques with an overlying thrombus) and stable plaques with the best AUC values of 0.9631 ± 0.0088, accuracy of 89.98% ± 0.57%, sensitivity of 83.71% ± 1.71%, and specificity of 94.55% ± 0.48%.

Conclusions:

Vulnerable and stable plaque can be distinguished by SpTeT based features. The SpTeT features, following validation on larger datasets, could be established as effective and reliable imaging biomarkers for noninvasively assessing atherosclerotic risk.
Why Twitter Displaces Broadcast Sports Media: A Model
Authors: Hull Kevin , Lewis Norman P.
Published: March 2014

The rising popularity of Twitter and the concurrent decline in audience size for local television sportscasts has fueled concern that the new medium is displacing traditional broadcasters. A model is offered that identifies the salient latent constructs that make Twitter a more attractive medium for connected fans in ways that transcend Twitter’s obvious advantage in timeliness. Issues relating to Twitter’s brevity, the public–private blending of athletes, parasocial interaction between users and who they follow, community building, homophily, and self-presentation are all addressed. The model offers propositions that can be tested by future research and provides guidance to broadcasters willing to adapt to what Twitter offers. Understanding why Twitter engages sports fans in a manner unlike that of previous technologies offers application for sports broadcasters trying to maintain audience share, as well as guidance for researchers seeking to explain the allure of the 140-character medium.
Professional Sports Teams on Social Networks: A Comparative Study Employing the Facebook Assessment Index
Authors: Miranda Francisco Javier , Chamorro Antonio , Rubio Sergio , Rodriguez Oscar
Published: March 2014

Professional sports teams are increasingly using social networks to better connect their sports and businesses to fans and the general public with the aim of providing team-related information, fostering fandom, and building team reputation. However, few, if any, studies have been done that analyze and evaluate the efficacy of this important portion of the professional sports business model from an informationmanagement perspective. This study employs the Facebook Assessment Index (FAI) to effectively compare, assess, and rank the Facebook sites of top European and North American professional teams. The study also shows how information artifacts in sports can be systematically analyzed, evaluated, and compared. In more general terms, the findings and analysis demonstrate how the information perspective can serve as a novel theoretical lens and important dimension in sport management. The results of the study show large differences between teams in the 3 FAI dimensions and a great improvement opportunity in the use of Facebook as a marketing tool. These results not only serve to create a ranking of sport teams but also can be used by sport managers for social-media-benchmarking analysis.
Inclusion of Persons With Disabilities Through Media Sports: Attitudinal and Behavioral News-Framing Effects
Authors: von Sikorski Christian , Schierl Thomas
Published: March 2014

Previous studies have demonstrated that the media, by specifically framing news articles, may systematically affect a nondisabled recipient’s perception of athletes with disabilities (AWDs). However, it remains unclear how specific sports news frames affect a recipient’s quality perception of a journalistic product and if news frames further affect an individual’s postexposure behavior in social interaction with a person with a disability (PWD). To shed some light on these potential news-framing effects, 2 experimental studies (between-subjects designs) were conducted. Study 1 revealed systematic news framing’s effects on recipients’ attitudes toward a depicted AWD and showed effects on a recipient’s perceived quality of a news story. Study 2 further revealed that specific news frames may (automatically) affect a recipient’s behavior (e.g., verbal communication performance, visual attention/ eye contacts) in a subsequent face-to-face social interaction with a PWD. The findings are discussed regarding their implications for the journalistic coverage of disability sports in the media.
“Smiles and Laughs—All Teeth Intact”: A Cultural Perspective on Mediated Women’s Handball in Norway
Authors: Broch Trygve B.
Published: March 2014

This article explores gendered sport communication in Norway. The data highlight Norwegian TV2’s live game commentaries of the 2009 women’s handball world championships, as well as live and studio commentary and journalistic reports concerning the Norwegian national women’s handball team from 2009 to 2013. The narrative-analytic approach is structural-hermeneutic and concerned with processes of meaning making. Instead of reading off gender/macrostructure in data, this project maps the semiotic culture structure of mediated women’s handball and shows how gendered meaning is creatively used to inform understandings of female handballers’ situated practices. The analysis first outlines the cultural binaries that constrain the media presentations of Norwegian women’s handball, then scrutinizes how gendered conceptions of sport and female athletes are used to understand this binary culture structure. Analytically revealed is a staging of Norwegian women’s handball that portrays successful and powerful female bodies’ contextual conduct. Norwegian women handballers are playing the aggressive and physically violent game in what is analyzed as a gender-appropriate manner.
Huwe1-Mediated Ubiquitylation of Dishevelled Defines a Negative Feedback Loop in the Wnt Signaling Pathway
Authors: de Groot Reinoud E. A. , Ganji Ranjani S. , Bernatik Ondrej , Lloyd-Lewis Bethan , Seipel Katja , Šedová Kateřina , Zdráhal Zbyněk , Dhople Vishnu M. , Dale Trevor C. , Korswagen Hendrik C. , Bryja Vitezslav
Published: March 2014

By ubiquitylating a protein interaction domain in Dishevelled, Huwe1 acts as a negative feedback regulator of Wnt signaling.
Mechano-Chemo Transduction Tunes the Heartstrings
Authors: Prosser Benjamin L. , Ward Christopher W.
Published: March 2014

Interplay between mechanical and chemical cues modulates the signaling pathways that are activated in contracting heart cells.
Hexing Complement
Authors: Hurtley Stella M.
Published: March 2014

Hexameric platforms of antibodies on the cell surface trigger the complement cascade.
Touchy-Feely Genes
Authors: Zahn Laura
Published: March 2014

The
stumble
gene in flies is required in neurons that sense joint angles.
Epidemiology and Clinical Outcomes of Patients with Carbapenem-Resistant Klebsiella pneumoniae Bacteriuria
Authors: Qureshi Zubair A. , Syed Alveena , Clarke Lloyd G. , Doi Yohei , Shields Ryan K.
Published: March 2014

Carbapenem-resistant
Klebsiella pneumoniae
(CRKP) bacteriuria is a frequently encountered clinical condition, but its clinical impact is unknown. We conducted a retrospective cohort study to define the epidemiology and outcomes for patients with CRKP bacteriuria. Patients with positive urine cultures for CRKP were classified as having asymptomatic bacteriuria (ASB) or symptomatic urinary tract infection (UTI). Among 105 patients with CRKP bacteriuria, 80% (84/105 patients) and 20% (21/105 patients) had ASB and UTI, respectively. Older age (
P
= 0.002) and higher Charlson's comorbidity index scores (
P
= 0.001) were associated with ASB. The median duration of hospitalization prior to CRKP bacteriuria was significantly longer for patients with ASB versus UTI (8.5 versus 2 days;
P
= 0.05). In multivariate analysis, male sex (odds ratio [OR], 4.69 [95% confidence interval (CI), 1.44 to 15.26];
P
= 0.01), solid-organ transplantation (OR, 4.50 [95% CI, 1.39 to 14.52];
P
= 0.01), and neurogenic bladder (OR, 18.62 [95% CI, 1.75 to 197.52];
P
= 0.01) were independently associated with UTI. Ten percent (8/84) of the patients with ASB received antimicrobial therapy. The treatment success rate for patients with UTIs was 90% (19/21 patients), including all patients who received doxycycline (
n
= 9). The overall 30-day mortality rate was 6% (6/105 patients); the deaths were unrelated to CRKP infections. Secondary CRKP infections, including UTIs, were notably absent among patients with ASB who were followed for 90 days. In conclusion, identification of CRKP in the urine was most commonly associated with ASB and did not lead to subsequent infections or death among asymptomatic patients. Factors associated with UTIs included male sex, solid-organ transplantation, and neurogenic bladder. Doxycycline may be an effective therapy for CRKP UTIs.
Pseudomonas aeruginosa Ceftolozane-Tazobactam Resistance Development Requires Multiple Mutations Leading to Overexpression and Structural Modification of AmpC
Authors: Cabot Gabriel , Bruchmann Sebastian , Mulet Xavier , Zamorano Laura , Moyà Bartolomé , Juan Carlos , Haussler Susanne , Oliver Antonio
Published: March 2014

We compared the dynamics and mechanisms of resistance development to ceftazidime, meropenem, ciprofloxacin, and ceftolozane-tazobactam in wild-type (PAO1) and mutator (PAOMS, Δ
mutS
)
P. aeruginosa
. The strains were incubated for 24 h with 0.5 to 64× MICs of each antibiotic in triplicate experiments. The tubes from the highest antibiotic concentration showing growth were reinoculated in fresh medium containing concentrations up to 64× MIC for 7 consecutive days. The susceptibility profiles and resistance mechanisms were assessed in two isolated colonies from each step, antibiotic, and strain. Ceftolozane-tazobactam-resistant mutants were further characterized by whole-genome analysis through RNA sequencing (RNA-seq). The development of high-level resistance was fastest for ceftazidime, followed by meropenem and ciprofloxacin. None of the mutants selected with these antibiotics showed cross-resistance to ceftolozane-tazobactam. On the other hand, ceftolozane-tazobactam resistance development was much slower, and high-level resistance was observed for the mutator strain only. PAO1 derivatives that were moderately resistant (MICs, 4 to 8 μg/ml) to ceftolozane-tazobactam showed only 2 to 4 mutations, which determined global pleiotropic effects associated with a severe fitness cost. High-level-resistant (MICs, 32 to 128 μg/ml) PAOMS derivatives showed 45 to 53 mutations. Major changes in the global gene expression profiles were detected in all mutants, but only PAOMS mutants showed
ampC
overexpression, which was caused by
dacB
or
ampR
mutations. Moreover, all PAOMS mutants contained 1 to 4 mutations in the conserved residues of AmpC (F147L, Q157R, G183D, E247K, or V356I). Complementation studies revealed that these mutations greatly increased ceftolozane-tazobactam and ceftazidime MICs but reduced those of piperacillin-tazobactam and imipenem, compared to those in wild-type
ampC
. Therefore, the development of high-level resistance to ceftolozane-tazobactam appears to occur efficiently only in a
P. aeruginosa
mutator background, in which multiple mutations lead to overexpression and structural modifications of AmpC.