bluuebunny/crossref_metadata_2025 huggingface dataset:
Coplanar waveguide‐fed dual‐band antenna for wireless local area network applications
Authors: Sun Xiaolei , Cheung S. W. , Yuk T. I.
Published: March 2012

This article presented a dual‐band monopole antenna fed by a coplanar waveguide (CPW) for wireless device applications in the 802.11b/a wireless local area network (WLAN) standards. The antenna consists of a rectangular radiator, two rectangular slots cut on both sides of the radiator, a semiring slot on the radiator, and a CPW feed for easy integration with other components on the printed circuit board. Parametric studies are carried out on the semiring slot and rectangular slots. The rectangular radiator generates two resonant bands at about 2.4 GHz for the 802.11b standard and 5.5 GHz for the upper band of the 802.11a. The semiring slot forms a resonator/bandstop filter to separate the radiator into two parts, hence generating another resonant band at around 5 GHz to cover the lower band of the 802.11a standard. The two rectangular slots improve impedance matching for the 802.11a standard. Simulation and measurement results of the proposed antenna show good agreements. Results show that the proposed dual‐band antenna has good performances in terms of radiation pattern, peak gain, and radiation efficiency. The bandwidth for the 802.11a standard can be easily adjusted using dimensions of the semiring and rectangular slot, giving an easy way for engineers to design antennas for wireless device applications for the WLAN standards. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1391–1396, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26859
Eccentric exercise does not affect common drive in the biceps brachii
Authors: Beck Travis W. , Kasishke Paul R. , Stock Matt S. , DeFreitas Jason M.
Published: March 2012

Introduction:

The purpose of this study was to investigate the effects of eccentric exercise on common drive.

Methods:

Eleven men, age 23.6 ± 2.1 (mean ± SD) years, performed trapezoid isometric muscle actions of the dominant forearm flexors immediately before and after 1 of 2 interventions: (a) 6 sets of 10 maximal eccentric isokinetic muscle actions of the forearm flexors; or (b) 10 minutes of quiet resting. Surface electromyographic signals were recorded from the biceps brachii and decomposed into individual motor unit action potential trains. Mean firing rate patterns were calculated for each motor unit, and all possible combinations were cross‐correlated to measure common drive.

Results:

The peak cross‐correlation coefficients were generally in the 0.2–0.5 range and occasionally as high as 0.7.

Conclusion:

These coefficients were not, however, affected by the eccentric exercise, despite a 19.5% decrease in strength, indicating that the eccentric exercise did not affect common drive. Muscle Nerve, 2012
Changes in human muscle oxygen saturation and mean fiber conduction velocity during intense dynamic exercise—effect of muscular training status
Authors: Kilen Anders , Gizzi Leonardo , Jensen Bente Rona , Farina Dario , Nordsborg Nikolai Baastrup
Published: March 2012

Introduction: In this study we investigated whether an association exists between muscle fiber conduction velocity (MFCV) and local muscle oxygen saturation (StO2) in the superficial part of the latissimus dorsi muscle of runners and swimmers during exhaustive dynamic exercise. Methods: Participants performed arm cranking with increasing intensity until exhaustion. Results: Runners' MFCV was unchanged with increasing arm‐cranking exercise intensity, but was higher (P < 0.05) than swimmers' MFCV at the same workload. Swimmers' MFCV increased (P < 0.05) with increasing exercise intensity and reached values at exhaustion similar to those of the runners. StO2 was similar in swimmers and runners at rest and decreased with increasing exercise intensity. StO2 was higher (P < 0.05) at the same workload in swimmers compared with runners. StO2 and MFCV were significantly but very weakly correlated in both swimmers and runners. Conclusion: No association exists between surface MFCV and StO2 in either trained or untrained human skeletal muscle during exhaustive intense dynamic exercise. Muscle Nerve, 2012
Genitourinary dysfunction in male rats after bilateral neurectomy of the motor branch of the sacral plexus
Authors: Juárez Margarita , Hernández Isela , Cruz Yolanda
Published: March 2012

Aims

To determine the contribution of the striated musculature anatomically related to the urethra on urinary continence in conscious male rats. We tested whether the bilateral neurectomy of the motor branch of the sacral plexus (MBSP), a nerve that innervates the bulbospongiosus, ischiocavernosus, and external urethral sphincter, is a reliable procedure to induce changes in voiding pattern that can be used as indicators of urinary incontinence in unanesthetized male rats.

Methods

Micturition behavior was videotaped and urinary parameters measured 24 h before and at day 2 and 10 after surgery.

Results

Intact animals have a stereotyped behavior of micturition consisting in urination in the corner of the cage. Neurectomized animals lost place preference for voiding demonstrated by leakage of urine throughout the cage while eating, walking, or sleeping. Voiding frequency was double and voiding duration was triple the amount before surgery. Urine flow rate and voiding volume were also significantly decreased. Necropsy showed that 10 days post‐denervation semen material was accumulated in the urethra and in the bladder.

Conclusion

In male rats the perineal striated muscles are crucial to maintaining normal urinary continence, preventing retrograde ejaculation, and to expelling urine and seminal secretions. Bilateral neurectomy of the MBSP may not be appropriate for long term survival urinary studies because effects on urinary parameters can be contaminated and/or masked by impaired seminal fluid expulsion, as a consequence of impairment of striated urethral muscle function. Neurourol. Urodynam. 31:1288–1293, 2012. © 2012 Wiley Periodicals, Inc.
Explicit high‐order time stepping based on componentwise application of asymptotic block Lanczos iteration
Authors: Lambers James V.
Published: March 2012

This paper describes the development of explicit time stepping methods for linear PDEs that are specifically designed to cope with the stiffness of the system of ODEs that results from spatial discretization. As stiffness is caused by the contrasting behavior of coupled components of the solution, it is proposed to adopt a componentwise approach in which each coefficient of the solution in an appropriate basis is computed using an individualized approximation of the solution operator. This has been accomplished by Krylov subspace spectral (KSS) methods, which use techniques from ‘matrices, moments and quadrature’ to approximate bilinear forms involving functions of matrices via block Gaussian quadrature rules. These forms correspond to coefficients with respect to the chosen basis of the application of the solution operator of the PDE to the solution at an earlier time. In this paper, it is proposed to substantially enhance the efficiency of KSS methods through the prescription of quadrature nodes on the basis of asymptotic analysis of the recursion coefficients produced by block Lanczos iteration for each Fourier coefficient as a function of frequency. The potential of this idea is illustrated through numerical results obtained from the application of the modified KSS methods to diffusion equations and wave equations. Copyright © 2012 John Wiley & Sons, Ltd.
A Duhamel approach for forced vibrations of rotating axisymmetric bodies
Authors: Carmignani C. , Forte P. , Melani G.
Published: March 2012

In this work a novel approach for the determination of the dynamic behaviour of a rotating device subject to forces fixed with respect to a stationary reference system is developed. The procedure can be applied to any axisymmetric rotating structure and it is particularly convenient for components of complex geometry for which an accurate dynamic characterization is fundamental. It is based on the application of Duhamel's integral. The time evolution of the system is obtained with the determination of the impulse response of the body using one single finite element transient analysis. By combining the results of the transient analysis with the time history of the forces applied to the rotating body, it is possible to determine the ground‐based vibration response of the component. Copyright © 2012 John Wiley & Sons, Ltd.
What drives breast cancer heterogeneity: oncogenic events or cell of origin?
Authors: Ginestier Christophe , Charafe‐Jauffret Emmanuelle , Birnbaum Daniel
Published: March 2012

Breast cancer is known to show considerable inter‐tumoural heterogeneity. It is widely accepted that combinations of oncogenic events have a major role in determining tumour phenotype. However, accumulating evidence suggests that the identity of the cell that acquires the first oncogenic event, the so‐called cell of origin, may define the molecular subtype of the resulting tumour. Recent work published in the Journal of Pathology by Natrajan and colleagues questions the origin of breast cancer heterogeneity. After studying BRCA1 tumours, they suggest that genomic alterations are not sufficient to determine tumour behaviour. These and other recent observations underscore the importance of defining what is causing tumour heterogeneity, so that appropriate therapy can be given. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Haploidentical bone marrow transplantation in Mexico
Authors: Vázquez‐Meraz José Eugenio , Arellano‐Galindo José , Mendoza‐García Emma , Jiménez‐Hernández Elva , Avalos Armando Martínez , Guadarrama Norma Velázquez , Arangure Juan Manuel Mejía
Published: March 2012

Haploidentical hematopoietic cell transplantation using CD34+ cells depleted of T lymphocytes by the CliniMACS is a treatment for hematological malignancy. We report on four Mexican children, three with acute lymphocytic leukemia and one with chronic myelocytic leukemia, who was transplanted with 12 × 106 CD34+ stem cells/kg body weight (98% of purity) with a follow‐up of $9{\textstyle{{1} \over {2}}}$ years. The engraftment was successful in three of the four children. All showed cytomegalovirus reactivation, and one died because of graft rejection and infectious complication. The risk of infections was a major problem. Pediatr Blood Cancer 2012; 59: 950–952. © 2012 Wiley Periodicals, Inc.
An exploratory epidemiological study of Langerhans cell histiocytosis
Authors: Venkatramani Rajkumar , Rosenberg Shira , Indramohan Gitanjali , Jeng Michael , Jubran Rima
Published: March 2012

We explored potential risk factors associated with Langerhans cell histiocytosis (LCH) in a predominantly Hispanic population in Los Angeles. Sixty children with LCH (cases) and, 150 randomly selected patients (controls) were interviewed. There was no statistically significant difference between cases and controls in the following: Family history of thyroid disease, smokers in the family, maternal problems during pregnancy, and pesticide exposure. Cases were more likely to report a family history of cancer (OR 2.5), infection during infancy (OR 2.76), and parental occupational exposure to metal, granites, or wood dust (OR 2.48). Pediatr Blood Cancer 2012; 59: 1324–1326. © 2012 Wiley Periodicals, Inc.
Health literacy variables related to parents' understanding of their child's cancer prognosis
Authors: Miller Kimberly S. , Vannatta Kathryn , Vasey Michael , Yeager Nicholas , Compas Bruce E. , Gerhardt Cynthia A.
Published: March 2012

Background

Obtaining an accurate understanding of a child's cancer prognosis can help parents make informed decisions about treatment. Research has shown that parents tend to overestimate their child's cancer prognosis relative to physicians. Thus, we examined whether the content of physician communication, parent sources of medical information, and parent demographic factors affected the association between oncologist and parent estimates of a child's cancer prognosis.

Procedure

Families were recruited 3–8 weeks after a child's new diagnosis or relapse of cancer. Parents (77 mothers; 42 fathers) completed questionnaires regarding their sources of medical information, age, and education. The child's oncologist reported on the content of their communication with parents regarding prognosis. Parents and oncologists estimated the child's chance of 5‐year survival using a visual‐analogue scale.

Results

Mothers and fathers reported a more favorable prognosis for their child, which was on average about 30% higher than oncologists. Time since diagnosis was correlated with less discrepancy between physician and mother prognosis ratings, with a similar trend noted for fathers. Agreement between oncologists and parents was better for younger fathers, but it was unrelated to physician communication, sources of medical information, or other demographic factors.

Conclusions

Fathers' age may be important to their understanding of their child's cancer prognosis, but we did not find support for other factors related to prognosis literacy. Given the homogeneity of our sample, future research should assess differences in parents' prognosis knowledge across cancer diagnosis, race, ethnicity, and socioeconomic status (SES), which may aid in developing interventions to improve parent understanding. Pediatr Blood Cancer 2012; 59: 914–918. © 2012 Wiley Periodicals, Inc.
Low‐velocity impact response in composite plates embedding shape memory alloy wires
Authors: Pappadà Silvio , Rametta Rocco , Largo Alessandro , Maffezzoli Alfonso
Published: March 2012

In this work, the behavior of hybrid composite plates, embedding superelastic shape memory alloy (SMA) wires, subjected to low‐velocity impacts was studied. The impact experiments were performed on glass reinforced thermoset composite plates containing 1% by volume of superelastic thin wires (0.1 mm of diameter) of a SMA. The specimens were impacted with instrumented drop weight impact equipment: different dropping heights were used to attain impact energies from 1 to 500 J. The shape and size of damaged area were analyzed using two nondestructive inspection methods: (1) light scattering under back illumination was used to observe minor damages such as matrix cracks and fiber matrix debonding and (2) the size and shape of large damages such as delaminations were evaluated by infrared thermography. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
On the morphology of polymer‐based photovoltaics
Authors: Liu Feng , Gu Yu , Jung Jae Woong , Jo Won Ho , Russell Thomas P.
Published: March 2012

We review the morphologies of polymer‐based solar cells and the parameters that govern the evolution of the morphologies and describe different approaches to achieve the optimum morphology for a BHJ OPV. While there are some distinct differences, there are also some commonalities. It is evident that morphology and the control of the morphology are important for device performance and, by controlling the thermodynamics, in particular, the interactions of the components, and by controlling kinetic parameters, like the rate of solvent evaporation, crystallization and phase separation, optimized morphologies for a given system can be achieved. While much research has focused on P3HT, it is evident that a clearer understanding of the morphology and the evolution of the morphology in low bad gap polymer systems will increase the efficiency further. While current OPVs are on the verge of breaking the 10% barrier, manipulating and controlling the morphology will still be key for device optimization and, equally important, for the fabrication of these devices in an industrial setting. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Complex Responses of Microorganisms as a Community to a Flowing Atmospheric Plasma
Authors: Bayliss Danny L. , Walsh James L. , Iza Felipe , Shama Gilbert , Holah John , Kong Michael G.
Published: March 2012

It is well known that microorganisms are highly adaptable to changing microenvironments and to a diversity of external stresses. To investigate this, a vacuum filtration technique was used to deposit Listeria innocua cells in a single monolayer onto a membrane and a pulsed radio‐frequency atmospheric plasma plume was used to treat such samples. Unexpectedly however, the resulting inactivation kinetics were biphasic despite the initial homogeneity. This paper reveals complex cascading events in the microbial community, starting with the emergence of discrete isles of cell aggregates, through their evolution into what we refer to as “cell refuges” that protect viable cells from subsequent plasma treatment and finally, the disintegration of the cell refuges leaving only a thin layer of fragmented cell debris. It is shown that plasma‐mediated cell aggregates and cell refuges introduce heterogeneity and are key to explaining the biphasic inactivation kinetics. The evolving surface architecture of the bacterial community could lead to the regulation of plasma species that the bacteria come to be exposed to. All of these factors could strongly affect the role played by charged plasma species involved in plasma–cell interactions. The complex and dynamically evolving responses of the bacteria to the gaseous plasma do not conform to the spatial distribution of the plasma, thus representing a process of self‐organization. Plasma‐mediated self‐organization of cell refuges and their selective screening of plasma species are perhaps only early signs of the undoubtedly sophisticated ability of microorganisms as a community to respond to the action of plasmas.

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Evidence for fractional filling in ultrathin GaInN/GaN multiple‐quantum wells
Authors: Tit Nacir
Published: March 2012

The (Ga1 − xInxN)Nw/GaN single‐ and multiple‐quantum wells (SQWs, MQWs) are theoretically investigated using the sp3s* tight‐binding (TB) method, with inclusion of spin–orbit coupling. Because of the huge mismatch in both the lattice constant and the energy gap between the constituent materials, two trends are shown to clearly put on display: (i) the existence of two types of confinement characters inside the deep wells of GaInN. The bound states at the bottom of the well are found to be singlets and to follow the power‐law quantum confinement (QC) character, similar to the case of a single particle in a quantum box. Whereas the bound states at the top of the well follow the exponential localization as being relatively weaker in their QC characters. (ii) In the limit of ultrathin quantum wells (QWs), the indium content is found to be restricted to remain low if coherent growth is aimed. This restriction is found to be natural as a compromise to maintain the growth free of misfit dislocations. For instance, in case of 1‐ML thick QWs, the indium content is found to be as low as ranging in the interval 0.15 < x < 0.25. Such restriction is corroborated by recent experimental evidence. The favorable modeling of our theoretical results to recent photoluminescence data further support our claims.
Inhibitory Effect of Ethanol Extract of Magnolia officinalis on Memory Impairment and Amyloidogenesis in a Transgenic Mouse Model of Alzheimer's Disease via Regulating β‐Secretase Activity
Authors: Lee Young‐Jung , Choi Dong‐Young , Han Sang Bae , Kim Young Hee , Kim Ki Ho , Hwang Bang Yeon , Kang Jong‐Koo , Lee Beom Jun , Oh Ki‐Won , Hong Jin Tae
Published: March 2012

Alzheimer's disease (AD) is the most common form of dementia and is characterized by deposition of amyloid beta (Aβ) in the brain. The components of the herb Magnolia officinalis are known to have antiinflammatory, antioxidative and neuroprotective activities. In this study we investigated the effects of ethanol extract of M. officinalis on memory dysfunction and amyloidogenesis in a transgenic mouse model of AD. Oral pretreatment of ethanol extract of M. officinalis (10 mg/kg in 0.05% ethanol) into drinking water for 3 months inhibited memory impairment and Aβ deposition in the brain of Tg2576 mice. Ethanol extract of M. officinalis also decreased activity of β‐secretase, cleaving Aβ from amyloid precursor protein (APP), and expression of β‐site APP cleaving enzyme 1 (BACE1), APP and its product, C99. Our results showed that ethanol extract of M. officinalis effectively prevented memory impairment via down‐regulating β‐secretase activity. Copyright © 2012 John Wiley & Sons, Ltd.
Topical Application of Fucoidan Improves Atopic Dermatitis Symptoms in NC/Nga Mice
Authors: Yang Jae‐Ho
Published: March 2012

Fucoidan is a sulphated polysaccharide extracted from brown seaweed and possesses a wide range of pharmacological properties including antiallergic and immunologic activities. The present study attempted to examine the effectiveness of fucoidan from Undaria pinnatifida in the treatment of atopic dermatitis (AD) in the NC/Nga mice model. Three per cent fucoidan or 0.1% dexamethasone was topically applied to the dorsal skin of AD‐induced mice for 4 weeks. The dermatitis severity scores and scratch counts of fucoidan or dexamethasone‐treated animals were significantly lower than the control group. Histological analysis showed that the number of mast cells infiltrating into skin lesions and the epidermis thickness were significantly decreased after the treatments. Levels of serum histamine and IgE were also decreased. There was no significant difference on improvement of AD‐like symptoms between fucoidan and dexamethasone. To elucidate possible mechanism of action, effects of fucoidan on regulation of AD‐associated chemokines, such as thymus‐ and activation‐regulated chemokine (TARC), macrophage‐derived chemokine (MDC) and regulated upon activation, normal T‐cell expressed and secreted (RANTES) chemokine, were investigated in human epidermal keratinocytes. Fucoidan significantly inhibited mRNA expression of these chemokines in a dose‐dependent manner. This is the first animal study to demonstrate that fucoidan has significant effects on improving AD‐like conditions as effective as dexamethasone, a well‐recognized corticosteroid remedy for the disease. Copyright © 2012 John Wiley & Sons, Ltd.
Suppressive Effect of Flavonoids from Korean Citrus aurantium L. on the Expression of Inflammatory Mediators in L6 Skeletal Muscle Cells
Authors: Kim Jin‐A. , Park Hyeon‐Soo , Kang Sang‐Rim , Park Kwang‐Il , Lee Do‐Hoon , Nagappan ArulKumar , Shin Sung‐Chul , Lee Won‐Sup , Kim Eun‐Hee , Kim Gon‐Sup
Published: March 2012

Citrus fruits (Citrus aurantium L.) have long been used as a traditional herbal medicine. The benefits of the flavonoids found in Citrus aurantium L. include anti‐inflammation, anti‐cancer, anti‐viral and anti‐bacterial activities, and enhancement of the immune response. The study investigated the effect of the flavonoids isolated from Citrus aurantium L. native to Korea on the production of pro‐inflammatory mediators by blocking signal transduction mediated by nuclear factor‐kappa B (NF‐κB) and mitogen‐activated protein kinases (MAPKs) in lipopolysaccharide (LPS)‐induced L6 skeletal muscle cells. The flavonoids decreased the production of inducible nitric oxide synthase, cyclooxygenase‐2, interleukin‐6 and tumor necrosis factor‐alpha by suppressing NF‐κB and MAPKs signal pathways in LPS‐induced L6 skeletal muscle cells. These findings suggest that the flavonoids isolated from Korea Citrus aurantium L. might have anti‐inflammatory effects that regulate the expression of inflammatory mediators in L6 skeletal muscle cells. Copyright © 2012 John Wiley & Sons, Ltd.
Potential Antidepressant Activity of Areca catechu Nut via Elevation of Serotonin and Noradrenaline in the Hippocampus of Rats
Authors: Abbas Ghulam , Naqvi Sabira , Erum Shaista , Ahmed Shakil , Atta‐ur‐Rahman  , Dar Ahsana
Published: March 2012

The current study was aimed at investigating the potential antidepressant activity of Areca catechu nut ethanol extract and its various fractions using behavioral (acute and sub‐chronic forced swim tests) and biochemical (monoamines and their metabolite levels using high performance liquid chromatography) tests. The areca nut ethanol extract and its aqueous fraction exhibited antidepressant activity in both acute and sub‐chronic forced swim tests (IC50 ~ 50 and 20 mg/kg, respectively), which was further confirmed by unaltered locomotor (horizontal and vertical) activities of rats in the activity cage. Phytochemical analysis revealed that saponins of areca nut may be the active component in its antidepressant action. The rats treated sub‐chronically with areca nut extract displayed toxic effects, whereas its active aqueous fraction was non‐toxic, indicating the presence of different constituents for antidepressant and toxic effects. In the hippocampus of rats, the areca nut extract (50 mg/kg) and aqueous fraction (20 mg/kg) caused a significant elevation of serotonin (around 35%) and noradrenaline (around 30%) compared with the control (261 ± 25 and 512 ± 29 ng/g, respectively). In conclusion, the areca nut possesses potential antidepressant effect via the elevation of serotonin and noradrenaline. Copyright © 2012 John Wiley & Sons, Ltd.
Monitoring toxigenic Microcystis strains in the Missisquoi bay, Quebec, by PCR targeting multiple toxic gene loci
Authors: Ngwa Felexce , Madramootoo Chandra , Jabaji Suha
Published: March 2012

The increasing incidence of mixed assemblages of toxic and nontoxic cyanobacterial blooms in Quebec's freshwater bodies over the last decade, coupled with inherent inadequacies of current monitoring approaches, warrants development of sensitive and reliable tools for assessing the toxigenic potential of these water blooms. In this study, we applied three independent polymerase chain reaction (PCR) assays that simultaneously target the microcystin synthetase (mcy) genes A, E, and G to rapidly and reliably detect and quantify potentially toxic Microcystis genotypes in the Missisquoi bay, Quebec, Canada. Linear regressions of quantitative PCR threshold cycles (Ct) against the logarithm of their respective Microcystis cell number equivalents resulted in highly significant linear curves with coefficients of determination (R2) greater than 0.99 (p < 0.0001, n = 6) and reaction efficiencies of 91.0, 95.8, and 92.7%, respectively, for the mcyA, mcyE, and mcyG‐based quantitative real‐time PCR (qPCR) assays. The three assays successfully estimated potential microcystin‐producing Microcystis genotypes from all field samples. The proportions of MicrocystismcyA, mcyE, and mcyG genotypes to total Microcystis cell counts showed substantial spatial variability ranging between 1.7–21.6%, 1.9–11.2%, and 2.2–22.6%, respectively. Correlation of microscopically determined total Microcystis counts to qPCR‐based MicrocystismcyA, mcyE, or mcyG cell number equivalents resulted in highly significant associations with R2 > 0.90. Thus, PCR‐based assays targeting the mcyA, mcyG, and/or mcyE genes can serve as powerful screening tools for rapid and sensitive estimation of microcystin‐producing Microcystis genotypes in freshwater water bodies. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 440–451, 2014.
The surface reactivity and implied toxicity of ash produced from sugarcane burning
Authors: Le Blond Jennifer S. , Tomatis Maura , Horwell Claire J. , Dunster Christina , Murphy Fiona , Corazzari Ingrid , Grendene Francesca , Turci Francesco , Gazzano Elena , Ghigo Dario , Williamson Ben J. , Oppenheimer Clive , Fubini Bice
Published: March 2012

Sugarcane combustion generates fine‐grained particulate that has the potential to be a respiratory health hazard because of its grain size and composition. In particular, conversion of amorphous silica to crystalline forms during burning may provide a source of toxic particles. In this study, we investigate and evaluate the toxicity of sugarcane ash and bagasse ash formed from commercial sugarcane burning. Experiments to determine the main physicochemical properties of the particles, known to modulate biological responses, were combined with cellular toxicity assays to gain insight into the potential reactions that could occur at the particle‐lung interface following inhalation. The specific surface area of the particles ranged from ∼16 to 90 m2 g−1. The samples did not generate hydroxyl‐ or carbon‐centered radicals in cell‐free tests. However, all samples were able to ‘scavenge’ an external source of hydroxyl radicals, which may be indicative of defects on the particle surfaces that may interfere with cellular processes. The bioavailable iron on the particle surfaces was low (2–3 μmol m−2), indicating a low propensity for iron‐catalyzed radical generation. The sample surfaces were all hydrophilic and slightly acidic, which may be due to the presence of oxygenated (functional) groups. The ability to cause oxidative stress and membrane rupture in red blood cells (hemolysis) was found to be low, indicating that the samples are not toxic by the mechanisms tested. Cytotoxicity of sugarcane ash was observed, by measuring lactate dehydrogenase release, after incubation of relatively high concentrations of ash with murine alveolar macrophage cells. All samples induced nitrogen oxide release (although only at very high concentrations) and reactive oxygen species generation (although the bagasse samples were less potent than the sugarcane ash). However, the samples induced significantly lower cytotoxic effects and nitrogen oxide generation when compared with the positive control. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 503–516, 2014.
DynaChannAl: dynamic channel allocation with minimal end‐to‐end delay for two‐tier wireless sensor networks
Authors: Ko JeongGil , Mishra Amitabh
Published: March 2012

With recent advances in wireless networking and in low‐power sensor technology, wireless sensor networks (WSNs) have taken significant roles in various applications. Whereas some WSNs only require minimal bandwidth, newer applications operate with a noticeably larger amount of data. One way to deal with these applications is to maximize the available capacity by utilizing multiple wireless channels. We propose DynaChannAl, a distributed dynamic wireless channel allocation algorithm that effectively distributes nodes to multiple wireless channels in WSNs. Specifically, DynaChannAl targets applications where mobile nodes connect to preexisting wireless backbones and takes the expected end‐to‐end queuing delay as its core metric. We used the link quality indicator values provided by 802.15.4 radios to whitelist high‐quality links and evaluate these links with the aggregated queuing latency, making it useful for applications that require minimal end‐to‐end delay (i.e., health care). DynaChannAl is a lightweight and adoptable scheme that can be incorporated easily with predeveloped systems. As the first study to consider end‐to‐end latency as the core metric for channel allocation in WSNs, we evaluate DynaChannAl on a 45 node test bed and show that DynaChannAl successfully distributes source nodes to different channels and enables them to select channels and links that minimizes the end‐to‐end latency. Copyright © 2012 John Wiley & Sons, Ltd.
Partitive clustering (K‐means family)
Authors: Xiao Yu , Yu Jian
Published: March 2012

Partitional clustering is an important part of cluster analysis. Cluster analysis can be considered as one of the the most important approaches to unsupervised learning. The goal of clustering is to find clusters from unlabeled data, which means that data belonging to the same cluster are as similar as possible, whereas data belonging to different clusters are as dissimilar as possible. Partitional clustering is categorized as a prototype‐based model, i.e., each cluster can be represented by a prototype, leading to a concise description of the original data set. According to different definitions of prototypes, such as data point, hyperplane, and hypersphere, the clustering methods can be categorized into different types of clustering algorithms with various prototypes. Besides organizing these partitional clustering methods into such a unified framework, relations between some commonly used nonpartitional clustering methods and partitional clustering methods are also discussed here. We give a brief overview of clustering, summarize well‐known partitional clustering methods, and discuss the major challenges and key issues of these methods. Simple numerical experiments using toy data sets are carried out to enhance the description of various clustering methods. © 2012 Wiley Periodicals, Inc.

This article is categorized under:

Algorithmic Development > Structure Discovery

Fundamental Concepts of Data and Knowledge > Knowledge Representation

Technologies > Structure Discovery and Clustering
Pyrrole‐2‐carbaldehyde Thiosemicarbazonates of Nickel(II) and Palladium(II): Synthesis, Structure, and Spectroscopy
Authors: Lobana Tarlok S. , Kumari Poonam , Bawa Gagandeep , Hundal Geeta , Butcher Ray J. , Fernandez Francisco J. , Jasinski Jerry P. , Golen James A.
Published: March 2012

Complexes of pyrrole‐2‐carbaldehyde thiosemicarbazones, [(C4H4N4)(H)C2=N3–N2(H)–C1(=S)–N1HR; R = Ph, H2L1; Me, H2L2; H, H2L3] with nickel(II) and palladium(II) are described. The reaction of nickel(II) acetate with H2L1 in methanol in 1:1 molar ratio yielded a complex of composition, [Ni(κ2‐N3,S‐HL1)2] (1). Likewise reaction of NiCl2 with H2L2 in 1:1 molar ratio in acetonitrile in the presence of triethylamine base followed by the addition of pyridine did not yield the anticipated [Ni(κ3‐N4,N3,S‐L2)(py)] complex, moreover a bis‐square‐planar complex, [Ni(κ2‐N3,S‐HL2)2] (2) was formed. However, in the presence of bipyridine (bipy), it yielded the addition product, [Ni(κ2‐N3,S‐HL2)2(κ2‐N, N‐bipy)] (3). Reaction of PdCl2(κ2‐P, P–PPh2–CH2–PPh2) with H2L3 in toluene in the presence of triethylamine has yielded a complex of stoichiometry, [Pd(κ3‐N4,N3,S–L3)(κ1‐P–PPh2–CH2–P(O)Ph2] (4). The ligands (HL1)– and (HL2)– are chelating to NiII metal atom as anions binding through N3,S‐donor atoms with pendant pyrrole groups, and (L3)2– is chelating to the PdII metal atom as dianion through N4,N3,S‐donor atoms (pyrrole is N4‐bonded). Fourth site in 4 is bonded to one P‐donor atom of PPh2–CH2–P(O)Ph2, whose pendant –PPh2 group involves auto oxidation to –P(O)PPh2 during reaction. These complexes were characterized using analytical data, IR, NMR (1H, 31P) spectroscopy and X‐ray crystallography. Complexes 1, 2, and 4 have square‐planar arrangement, whereas complex 3 is octahedral.
The impact of emergency obstetric care training in Somaliland, Somalia
Authors: Ameh Charles , Adegoke Adetoro , Hofman Jan , Ismail Fouzia M. , Ahmed Fatuma M. , van den Broek Nynke
Published: March 2012

Objective

To provide and evaluate in‐service training in “Life Saving Skills – Emergency Obstetric and Newborn Care” in order to improve the availability of emergency obstetric care (EmOC) in Somaliland.

Methods

In total, 222 healthcare providers (HCPs) were trained between January 2007 and December 2009. A before–after study was conducted using quantitative and qualitative methods to evaluate trainee reaction and change in knowledge, skills, and behavior, in addition to functionality of healthcare facilities, during and immediately after training, and at 3 and 6 months post‐training.

Results

The HCPs reacted positively to the training, with a significant improvement in 50% of knowledge and 100% of skills modules assessed. The HCPs reported improved confidence in providing EmOC. Basic and comprehensive EmOC healthcare facilities provided 100% of expected signal functions—compared with 43% and 56%, respectively, at baseline—with trained midwives performing skills usually performed by medical doctors. Lack of drugs, supplies, medical equipment, and supportive policy were identified as barriers that could contribute to nonuse of new skills and knowledge acquired.

Conclusion

The training impacted positively on the availability and quality of EmOC and resulted in “up‐skilling” of midwives.
Medical Direction of Wilderness and Other Operational Emergency Medical Services Programs
Authors: Warden Craig R. , Millin Michael G. , Hawkins Seth C. , Bradley Richard N.
Published: March 2012

Within a healthcare system, operational emergency medical services (EMS) programs provide prehospital emergency care to patients in austere and resource-limited settings. Some of these programs are additionally considered to be wilderness EMS programs, a specialized type of operational EMS program, as they primarily function in a wilderness setting (eg, wilderness search and rescue, ski patrols, water rescue, beach patrols, and cave rescue). Other operational EMS programs include urban search and rescue, air medical support, and tactical law enforcement response. The medical director will help to ensure that the care provided follows protocols that are in accordance with local and state prehospital standards, while accounting for the unique demands and needs of the environment. The operational EMS medical director should be as qualified as possible for the specific team that is being supervised. The medical director should train and operate with the team frequently to be effective. Adequate provision for compensation, liability, and equipment needs to be addressed for an optimal relationship between the medical director and the team.
Openness versus secrecy? Historical and historiographical remarks
Authors: VERMEIR KOEN
Published: March 2012

Traditional historiography of science has constructed secrecy in opposition to openness. In the first part of the paper, I will challenge this opposition. Openness and secrecy are often interlocked, impossible to take apart, and they might even reinforce each other. They should be understood as positive (instead of privative) categories that do not necessarily stand in opposition to each other. In the second part of this paper, I call for a historicization of the concepts of ‘openness’ and ‘secrecy’. Focusing on the early modern period, I briefly introduce three kinds of secrecy that are difficult to analyse with a simple oppositional understanding of openness and secrecy. In particular, I focus on secrecy in relation to esoteric traditions, theatricality and allegory.
THE TIMING OF TORTIOUS AND CRIMINAL ACTIONS FOR THE SAME WRONG
Authors: Dyson Matthew
Published: March 2012

This paper traces a key example of the overlap between tort and crime and explains the impact of how disjointed English legal thinking has been. For about 400 years English civil courts have accepted some form of pre-eminence of the criminal law where civil and serious criminal liability co-exist. This has often been described as the rule that “a trespass merges in a felony” though a more neutral term would be a “timing rule”. The development of the timing rules casts light on how English legal reasoning has approached the relationship between the victim and the state, the procedural context of substantive rules and the impact rules in one area of law can have elsewhere.
In vitro screening for cestocidal activity of three species of Cassia plants against the tapeworm Raillietina tetragona
Authors: Kundu S. , Lyndem L.M.
Published: March 2012

Different species of Cassia plant are widely available in India and are commonly used either for their laxative, antimicrobial or antibacterial activity. In the present study the effectiveness in vitro of the crude alcoholic extracts of three species, namely Cassia alata, C. occidentalis and C. angustifolia, in the early paralysis and mortality of the fowl tapeworm Raillietina tetragona at concentrations ranging from 5 to 80 mg/ml was investigated. Time of paralysis and death were monitored frequently. Immediately after paralysis the tapeworms were processed for electron microscopic studies. While the untreated or control parasites survived for 81.93 ± 5.85 h, the parasites treated with C. alata took less time (1.68 ± 0.27 h) to be paralysed, followed by those treated with C. angustifolia (2.95 ± 0.29 h). Although C. occidentalis took more time (4.13 ± 0.31 h) to paralyse, in combination with either C. alata or C. angustifolia the time taken to paralyse became shorter. All the plant-treated parasites showed irrevocable changes in the scolex and proglottids as compared with the control, and these observations are comparable with those obtained with praziquantel. These results indicate that the three plants tested can be claimed to have anthelmintic activity in addition to their known properties, both when used individually and in combination. Further investigations will be required to evaluate their mechanism of action.
Nonlinear low-frequency structures in an electron–positron–ion plasma
Authors: MOOLLA S. , LAZARUS I. J. , BHARUTHRAM R.
Published: March 2012

Nonlinear ion cyclotron and ion-acoustic waves have been studied in an electron–positron–ion plasma. Using Boltzmann distributions for the electrons and positrons and fluid equations for the ions, a set of nonlinear equations in the rest frame of the propagating wave is derived and numerically solved for the electric field. A scan of parameter space reveals a range of solutions for the parallel electric field, from sinusoidal to sawtooth to highly spiky waveforms. The results are compared with satellite observations.
Exchange rate regimes in the major Latin American countries since the 1950s: lessons from history
Authors: Frenkel Roberto , Rapetti Martín
Published: March 2012

The paper analyses exchange rate regimes implemented by the major Latin American (LA) countries since the 1950s, with special attention to the period beginning in the 1970s. The aim is to evaluate the relationship between exchange rate regimes and macroeconomic performance. After an overview of the main trends followed by the major LA countries over the last 60 years, the paper focusses on regimes that were implemented (1) with stabilisation purposes (nominal anchor) and (2) with the aim of targeting competitive and stable real exchange rates. These sections analyse in greater detail some important links between exchange rate regimes and macroeconomic performance. The paper closes with an assessment of the experiences with exchange rate regimes in LA.
On the Seifert graphs of a link diagram and its parallels
Authors: HUGGETT STEPHEN , MOFFATT IAIN , VIRDEE NATALIA
Published: March 2012

Recently, Dasbach, Futer, Kalfagianni, Lin and Stoltzfus extended the notion of a Tait graph by associating a set of ribbon graphs (or, equivalently, cellularly embedded graphs) to a link diagram. Here we focus on Seifert graphs, which are the ribbon graphs of a knot or link diagram that arise from Seifert states. We provide a characterization of Seifert graphs in terms of Eulerian subgraphs. This characterization can be viewed as a refinement of the fact that Seifert graphs are bipartite. We go on to examine the family of ribbon graphs that arises by forming the parallels of a link diagram and determine how the genus of the ribbon graph of ar-fold parallel of a link diagram is related to that of the original link diagram.
The effects of first- and second-language proficiency on conflict resolution and goal maintenance in bilinguals: Evidence from reaction time distributional analyses in a Stroop task
Authors: TSE CHI-SHING , ALTARRIBA JEANETTE
Published: March 2012

By administering a Stroop task to college-student bilinguals varied in self-rated first- (L1) and second-language (L2) proficiency, the current study examined the effects of L1 and L2 proficiencies on selective attention performance. We conducted ex-Gaussian analyses to capture the modal and positive-tail components of participants' reaction time distributions. Both L1 and L2 proficiencies were associated with a shift of reaction time distributions in incongruent trials, relative to congruent trials, and the tail size of reaction time distributions regardless of trial types. This suggests that bilinguals' L1 and L2 proficiencies could affect their Stroop performance via modulating their conflict resolution and goal maintenance abilities.
Syntactic transfer in English-speaking Spanish learners
Authors: MORETT LAURA M. , MACWHINNEY BRIAN
Published: March 2012

Competition Model studies of second language learners have demonstrated that there is a gradual replacement of first language cues for thematic role assignment by second language cues. The current study introduced two methodological innovations in the investigation of this process. The first was the use of mouse-tracking methodology (Spivey, 2007) to assess the online process of thematic role assignment. The second was the inclusion of both a task with language-specific cues and a task with language-common cues. The results of the language-common cue task indicated that, as English-dominant learners become more balanced between English and Spanish, they rely increasingly on a coalition between the animacy cue and the subject–verb agreement cue. However, the results of the language-specific cue task reveal that learners also rely on the cue of prepositional case marking in Spanish and nominal case marking in English. These results provide evidence of forward transfer, backward transfer, and rapid acquisition of cue-based sentence interpretation strategies in second language learning.
Fear of Failure, Disorganization, and Subjective Well-Being in the Context of Preparing for an Exam
Authors: Berger Stéphanie , Freund Alexandra M.
Published: March 2012

The present study investigated the relationships between fear of failure, disorganization, and affective well-being while preparing for a college exam. The study comprised a sample of N = 280 students and used a longitudinal crosslagged design. The results of structural equation modeling partly supported the hypotheses. Fear of failure was found to be related to disorganization in the cross-sectional but not in the longitudinal data. As expected, fear of failure negatively predicted change in affective well-being. Affective well-being predicted change in disorganization during exam preparation and exam performance. Contrary to our expectations, however, disorganization did not predict exam performance over and above affective well-being. Implications for further studies investigating the role of well-being in the learning context are discussed.
Wirkungsebenen der künstlerischen Therapien
Authors: Donat Andreas
Published: March 2012

Zusammenfassung. Die Frage nach dem Verbindenden und Unterscheidenden der einzelnen Therapieansätze ist die Ausgangssituation meines Artikels. Anhand von sieben „Säulen” werden die Grundstrukturen therapeutischen Handelns aufgezeigt: der künstlerische Prozess, die Heil-Geste, die Begegnung, die Stärkung der Persönlichkeit, das Menschenbild und die damit verbundenen Begrifflichkeiten, Vertrautheit mit den eigenen Heil-Gesten, das Ideal. Abschließende Gedanken weisen auf die noch zu entfaltende gesellschaftliche Bedeutung der künstlerischen Therapien hin.
Kreative Bewältigung einer Lebenskrise mit Hilfe der Poesietherapie
Authors: Heimes Silke , Seizer Hans-Ulrich , Soyka Michael
Published: March 2012

Zusammenfassung. Anliegen: Die heilende Wirkung von Sprache und Schrift, in Form der in Amerika längst etablierten Poesietherapie, kann man sich auch in der deutschen Psychotherapie zu Nutze machen. Methodik: Vorgestellt wird der Fall eines 43-jährigen Patienten mit Erschöpfungssyndrom, der im Rahmen seiner 7-wöchigen stationären Behandlung zweimal wöchentlich an der Poesietherapie teilnahm. Ergebnis: Das subjektive Befinden des Patienten verbesserte sich in allen Bereichen. Mittels der Poesietherapie erlangte er eine bessere Selbstwahrnehmung und -erkenntnis, die ihn den Alltag leichter bewältigen ließ.