bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and Field Test of the Modified Draw‐a‐Scientist Test and the Draw‐a‐Scientist Rubric
Authors: Farland‐Smith Donna
Published: February 2012

Even long before children are able to verbalize which careers may be interesting to them, they collect and store ideas about scientists. For these reasons, asking children to draw a scientist has become an accepted method to provide a glimpse into how children represent and identify with those in the science fields. Years later, these representations may translate into students' career choices. Since 1995, children's illustrations of scientists have been assessed by the Draw‐a‐Scientist Checklist (DAST‐C). The checklist was created from the common aspects or features found in illustrations from previous studies and were based initially on the scientists, broken down into “stereotypical” and “alternative” images shown in the drawings. The purpose of this article is to describe the development, field test, and reliability of the modified DAST Test and the DAST Rubric designed as an improvement of the DAST‐C to provide a more appropriate method of assessing students' drawings of scientists. The combination of the modified DAST and the DAST Rubric brings more refinement as it enables clarities to emerge and subsequently increased detail to what one could ascertain from students about their mental images of scientists.
Evaluating the performance of different procedures for constructing confidence intervals for coefficient alpha: A simulation study
Authors: Cui Ying , Li Johnson
Published: February 2012

Reliability is one of the most important aspects of testing in educational and psychological measurement. The construction of confidence intervals for reliability coefficients has important implications for evaluating the accuracy of the sample estimate of reliability and for comparing different tests, scoring rubrics, or training procedures for raters or observers. The present simulation study evaluated and compared various parametric and non‐parametric methods for constructing confidence intervals of coefficient alpha. Six factors were manipulated: number of items, number of subjects, population coefficient alpha, deviation from essentially parallel condition, item response distribution and type. The coverage and width of different confidence intervals were compared across simulation conditions.
A One-Dimensional Model of the Spinal Cerebrospinal-Fluid Compartment
Authors: Cirovic Srdjan , Kim Minsuok
Published: February 2012

Modeling of the cerebrospinal fluid (CSF) system in the spine is strongly motivated by the need to understand the origins of pathological conditions such as the emergence and growth of fluid-filled cysts in the spinal cord. In this study, a one-dimensional (1D) approximation for the flow in elastic conduits was used to formulate a model of the spinal CSF compartment. The modeling was based around a coaxial geometry in which the inner elastic cylinder represented the spinal cord, middle elastic tube represented the dura, and the outermost tube represented the vertebral column. The fluid-filled annuli between the cord and dura, and the dura and vertebral column, represented the subarachnoid and epidural spaces, respectively. The system of governing equations was constructed by applying a 1D form of mass and momentum conservation to all segments of the model. The developed 1D model was used to simulate CSF pulse excited by pressure disturbances in the subarachnoid and epidural spaces. The results were compared to those obtained from an equivalent two-dimensional finite element (FE) model which was implemented using a commercial software package. The analysis of linearized governing equations revealed the existence of three types of waves, of which the two slower waves can be clearly related to the wave modes identified in previous similar studies. The third, much faster, wave emanates directly from the vertebral column and has little effect on the deformation of the spinal cord. The results obtained from the 1D model and its FE counterpart were found to be in good general agreement even when sharp spatial gradients of the spinal cord stiffness were included; both models predicted large radial displacements of the cord at the location of an initial cyst. This study suggests that 1D modeling, which is computationally inexpensive and amenable to coupling with the models of the cranial CSF system, should be a useful approach for the analysis of some aspects of the CSF dynamics in the spine. The simulation of the CSF pulse excited by a pressure disturbance in the epidural space, points to the possibility that regions of the spinal cord with abnormally low stiffness may be prone to experiencing large strains due to coughing and sneezing.
Shallow defect states in GaAs responsible for GaAs bandgap upconversion induced by electron beam during MBE growth
Authors: Tex David M. , Kamiya Itaru
Published: February 2012

Upconversion through excitation of bulk GaAs is investigated by change in crystal growth conditions with electron beam (e-beam). The upconverted photoluminescence intensity is enhanced several times by striking the source fluxes with e-beam during molecular beam epitaxy (MBE) growth. Experimental evidence for a shallow intermediate state being responsible for this upconversion is presented. It is suggested that the intermediate state may be formed by shallow exciton trap states induced by As anti-site defects, which can be increased with e-beam during MBE growth.
Probing temporal evolution of extreme ultraviolet assisted contamination on Ru mirror by x-ray photoelectron spectroscopy
Authors: Al-Ajlony A. , Kanjilal A. , Catalfano M. , Fields M. , Harilal S. S. , Hassanein A. , Rice B.
Published: February 2012

Extreme ultraviolet (EUV) radiation mediated carbon contamination and oxidation of the Ru mirror surface, and the corresponding impact on reflectivity were studied. In particular, time-dependent systematic decrease in EUV reflectivity with a 13.5 nm wavelength of light in high vacuum atmosphere was recorded and correlated with the change in chemical composition on the Ru surface as derived from in situ x-ray photoelectron spectroscopy (XPS). The contamination on Ru surface is caused by residual impurities of the test chamber. The recorded XPS spectra show a sudden increase in carbon concentration in the first 1 h followed by a slow but linear growth in the presence of EUV radiation. Further analyses show a slight increase in Ru oxide, whereas the concentration of water molecules decreases continuously. Moreover, the carbon monoxide level at the surface was stabilized after initial increase in concentration for an hour. The impact of water molecules and the accumulation of carbon atoms on the Ru surface are discussed in details.
Real-Time Assessment of Community Health Needs and Concerns
Authors: Cottler Linda B. , Nagarajan Rakesh
Published: February 2012

Interfacing the efforts of community health workers with Web-based systems will facilitate ongoing, real-time assessment of community member needs, concerns, and research opportunities.
Genomic and Attention Deficits
Authors: Nielson Carrie M.
Published: February 2012

Scientists link chromosomal aberrations in neurotransmitter receptor genes to attention deficit hyperactivity disorder in children.
The 6-PACK programme to decrease falls and fall-related injuries in acute hospitals: protocol for an economic evaluation alongside a cluster randomised controlled trial
Authors: Morello Renata , Barker Anna , Zavarsek Silva , Watts Jennifer J , Haines Terry , Hill Keith , Sherrington Cathie , Brand Caroline , Jolley Damien , Stoelwinder Just
Published: February 2012

Background

Falls are a common hospital occurrence complicating the care of patients. From an economic perspective, the impact of in-hospital falls and related injuries is substantial. However, few studies have examined the economic implications of falls prevention interventions in an acute care setting. The 6-PACK programme is a targeted nurse delivered falls prevention programme designed specifically for acute hospital wards. It includes a risk assessment tool and six simple strategies that nurses apply to patients classified as high-risk by the tool.

Objective

To examine the incremental cost-effectiveness of the 6-PACK programme for the prevention of falls and fall-related injuries, compared with usual care practice, from an acute hospital perspective.

Methods and design

The 6-PACK project is a multicentre cluster randomised controlled trial (RCT) that includes 24 acute medical and surgical wards from six hospitals in Australia to investigate the efficacy of the 6-PACK programme. This economic evaluation will be conducted alongside the 6-PACK cluster RCT. Outcome and hospitalisation cost data will be prospectively collected on approximately 16 000 patients admitted to the participating wards during the 12-month trial period. The results of the economic evaluation will be expressed as ‘cost or saving per fall prevented’ and ‘cost or saving per fall-related injury prevented’ calculated from differences in mean costs and effects in the intervention and control groups, to generate an incremental cost-effectiveness ratio (ICER).

Discussion

This economic evaluation will provide an opportunity to explore the cost-effectiveness of a targeted nurse delivered falls prevention programme for reducing in-hospital falls and fall-related injuries. This protocol provides a detailed statement of a planned economic evaluation conducted alongside a cluster RCT to investigate the efficacy of the 6-PACK programme to prevent falls and fall-related injuries.

Trial registration number

The protocol for the cluster RCT is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12611000332921).
The value of triple antibody (34βE12 + p63 + AMACR) cocktail stain in radical prostatectomy specimens with crushed surgical margins
Authors: Daoud Najla Al , Li Gangyong , Evans Andrew J , van der Kwast Theodorus H
Published: February 2012

Background

Triple antibody cocktail immunohistochemical staining is routinely used as an ancillary method to establish a diagnosis of prostate cancer in biopsies with small foci of atypical glands. Crush artefact can distort surgical margins in radical prostatectomy specimens, occasionally making it difficult to diagnose a positive margin.

Aim

To investigate the ability of a cocktail stain to distinguish carcinoma from benign prostatic glands at the edge of crushed margins in prostatectomy specimens.

Methods

10 radical prostatectomy specimens with crushed benign glands at the surgical margins, and 20 with crushed margins positive for carcinoma were retrieved from the pathology archives. The latter included 16 (80%) with positive apical margins, 2 (10%) incised intraprostatic margins, and 1 (5%) soft tissue margin. Two-colour triple antibody stain using a cocktail of antibodies against α-methylacyl coenzyme A racemase (AMACR), high molecular weight keratin and p63 was performed on all the selected cases.

Results

In 10/10 specimens with crushed benign glands, basal cell staining continued to be detectable, while AMACR staining was negative in all cases (0/10). In the positive margin cases, none of the crushed glands expressed basal cell marker staining (0/20), whereas 14/20 (70%) of the cases showed variable levels of AMACR positivity at the inked margin.

Conclusion

Two-colour triple antibody cocktail stain is useful in the assessment of most, but not all, surgical margins with crushed artefact in prostatectomy specimens by helping to establish whether glands are malignant or benign.
Assessment of a ‘fast-track’ referral service for intrauterine contraception following early medical abortion: Table 1
Authors: Cameron Sharon T , Berugoda Nayani , Johnstone Anne , Glasier Anna
Published: February 2012

Background

A ‘fast-track’ referral system for intrauterine contraception was established in 2007 between the medical abortion service at the Royal Infirmary of Edinburgh and the principal family planning clinic (FPC) in Edinburgh.

Methods

Case note review of women fast-tracked for intrauterine contraception after medical abortion between January 2007 and June 2009. Main outcome measures were numbers of women referred, attendance rates, interval to insertion, devices chosen and known complication rates.

Results

Of the 237 women referred, 126 (53%) attended for intrauterine contraception insertion. Attenders were slightly but significantly older than non-attenders (mean ages of 30 and 27 years, respectively;p=0.003), less likely to live in an area of deprivation (p=0.045) and were significantly more likely to have attended the FPC in the past (p<0.0001). Most attenders (90%;n=113) proceeded to have an intrauterine method inserted; 57% (n=64) chose the levonorgestrel intrauterine system and 43% (n=49) chose a copper intrauterine device. The median interval to insertion was 21 (range 0–54) days. Of those women (n=55) who attended for routine follow-up 6 weeks later (49%), there were four (7.2%) cases of expulsion, two (3.6%) requests for removal and four (7.2%) cases of suspected infection.

Conclusions

Only half the women fast-tracked for intrauterine contraception actually attended and these tended to be women who were pre-existing clients of the FPC. Consideration should therefore be given to provision of immediate insertion where possible.
MRSA contaminated venepuncture tourniquets in clinical practice
Authors: Elhassan Hassan A , Dixon Teresa
Published: February 2012

Introduction

Meticillin-resistant Staphylococcus aureus (MRSA) hospital-acquired infection is associated with increased patient mortality. National guidelines state that shared patient equipment must be cleaned after use. The authors sought to identify MRSA contamination in a sample of non-disposable venepuncture tourniquets and audit cleaning habits between patient contacts.

Materials and methods

Fifty tourniquets were collected from junior doctors, nursing staff and wards from two district general hospitals in Essex, UK in 2007. A questionnaire was completed at the time of collection for each tourniquet. The tourniquets were cultured using standard microbiology techniques.

Findings

18/50 (36%) tourniquets were positive for S aureus and of these 6/50 (12%) were MRSA positive. 33/43 (77%) healthcare professionals using non-disposable tourniquets for venepuncture made no attempts at cleaning their tourniquets. 10/43 (23%) staff admitted to cleaning their tourniquets. The tourniquets were used for an average of 14 weeks on approximately three different patients per day. 30/50 (60%) tourniquets were visibly soiled and of these 13 were blood stained and 20/50 (40%) appeared ‘clean’. Worn tourniquets when compared with the ‘clean’ tourniquets were more likely to be contaminated with S aureus, 15/30 (50%) vs 3/20 (15%), and MRSA 5/30 (17%) vs 1/20 (5%).

Conclusion

Non-disposable venepuncture tourniquets are contaminated with MRSA and pose a risk to patients. The majority of clinical staff do not clean them between patient contacts as recommended by guidelines. The use of non-disposable venepuncture tourniquets should be abandoned. The introduction of disposable tourniquets to clinical practice should be an adjunct to current measures for MRSA prevention.
THE STRUCTURES OF STATE SPACE CONCERNING QUANTUM DYNAMICAL SEMIGROUPS
Authors: BAUMGARTNER BERNHARD , NARNHOFER HEIDE
Published: February 2012

Each semigroup describing time evolution of an open quantum system on a finite dimensional Hilbert space is related to a special structure of this space. It is shown how the space can be decomposed into orthogonal subspaces: One part is related to decay, some subspaces of the other subspace are ranges of the stationary states. Specialities are highlighted where the complete positivity of evolutions is actually needed for analysis, mainly for evolution of coherence. Decompositions are done the same way for discrete as for continuous time evolutions, but they may show differences: Only for discrete semigroups there may appear cases of sudden decay and of perpetual oscillation. Concluding the analysis, we identify the relation of the state space structure to the processes of decay, decoherence, dissipation and dephasing.
THE EFFECT OF EXTREME CONFINEMENT ON THE NONLINEAR-OPTICAL RESPONSE OF QUANTUM WIRES
Authors: SHAFEI SHORESH , KUZYK MARK G.
Published: February 2012

This work focuses on understanding the nonlinear-optical response of a 1-D quantum wire embedded in 2-D space when quantum-size effects in the transverse direction are minimized using an extremely weighted delta function potential. Our aim is to establish the fundamental basis for understanding the effect of geometry on the nonlinear-optical response of quantum loops that are formed into a network of quantum wires. It is shown that in the limit of full confinement, the sum rules are obeyed when the transverse infinite-energy continuum states are included. While the continuum states associated with the transverse wavefunction do not contribute to the nonlinear optical response, they are essential to preserving the validity of the sum rules. This work is a building block for future studies of nonlinear-optical enhancement of quantum graphs (which include loops and bent wires) based on their geometry. These properties are important in quantum mechanical modeling of any response function of quantum-confined systems, including the nonlinear-optical response of any system in which there is confinement in at least one dimension, such as nanowires, which provide confinement in two dimensions.
LIGHT MODULATION ENABLED BY LIQUID CRYSTAL MICROFLOWS
Authors: CUENNET J. G. , VASDEKIS A. E. , DE SIO L. , PSALTIS D.
Published: February 2012

In a previous paper,1we proposed an optofluidic modulator based on peristaltic flow. A microchannel made of polydimethylsiloxane is filled with nematic liquid crystal molecules that align homeotropically in the steady state. Once we apply a periodic peristaltic flow through mechanical deformation of the channel, liquid crystal molecules tend to realign with the gradient velocity field and thus change their optical properties. In this paper, we focus on the channel deformation with the finite elements program Comsol®, and we highlight the limitations in frequency of such optofluidic components.
NEW APPROACHES FOR RESOURCE ALLOCATION VIA DEA MODELS
Authors: WU JIE , AN QINGXIAN
Published: February 2012

This paper focuses on the problem of resource allocation through data envelopment analysis. We propose three integrated models for allocating resources. The first model aims at minimizing the input consumption, the second one aims at maximizing the total outputs within the current resources, and the last one aims at maximizing the total outputs using the predicted resources in the next production season. Since the number of inputs or outputs is usually more than one, the abovementioned issue is often a multiple objective linear programming (MOLP) problem. Through the proportion of inputs (outputs) of new decision making unit (DMU) to the total inputs (outputs) of all old DMUs, we transform the MOLP problem into a single objective linear programming model. We assume that decision maker must ensure that the expected outputs of each DMU after allocation in the next production season are not less than this production season. All these proposed models have the same advantage that the results gained from the models are Pareto efficient. A numerical example of 25 supermarkets is used to illustrate our proposed approach.
HEURISTIC BIVARIATE FORECASTING MODEL OF MULTI-ATTRIBUTE FUZZY TIME SERIES BASED ON FUZZY CLUSTERING
Authors: NAN GUOFANG , ZHOU SHUAIYIN , KOU JISONG , LI MINQIANG
Published: February 2012

Fuzzy time series has been applied to forecast various domain problems because of its capability to deal with vagueness and incompleteness inherent in data. However, most existing fuzzy time series models cannot cope with multi-attribute time series and remain too subjective in the partition of the universe of discourse. Moreover, these models do not consider the trend factor and the corresponding external time series, which are highly relevant to target series. In the current paper, a heuristic bivariate model is proposed to improve forecasting accuracy, and the proposed model applies fuzzy c-means clustering algorithm to process multi-attribute fuzzy time series and to partition the universe of discourse. Meanwhile, the trend predictors are extracted in the training phase and utilized to select the order of fuzzy relations in the testing phase. Finally, the proper full use of the external series to assist forecasting is discussed. The performance of the proposed model is tested using actual time series including the enrollments at the University of Alabama, the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) and a sensor dataset. The experimental results show that the proposed model can be utilized for multi-attribute time series and significantly improves the average MAER to 1.19% when compared with other forecasting models.
Regulation and Function of the FGF23/Klotho Endocrine Pathways
Authors: Martin Aline , David Valentin , Quarles L. Darryl
Published: February 2012

Calcium (Ca2+) and phosphate (PO43−) homeostasis are coordinated by systemic and local factors that regulate intestinal absorption, influx and efflux from bone, and kidney excretion and reabsorption of these ions through a complex hormonal network. Traditionally, the parathyroid hormone (PTH)/vitamin D axis provided the conceptual framework to understand mineral metabolism. PTH secreted by the parathyroid gland in response to hypocalcemia functions to maintain serum Ca2+levels by increasing Ca2+reabsorption and 1,25-dihydroxyvitamin D [1,25(OH)2D] production by the kidney, enhancing Ca2+and PO43−intestinal absorption and increasing Ca2+and PO43−efflux from bone, while maintaining neutral phosphate balance through phosphaturic effects. FGF23 is a recently discovered hormone, predominately produced by osteoblasts/osteocytes, whose major functions are to inhibit renal tubular phosphate reabsorption and suppress circulating 1,25(OH)2D levels by decreasing Cyp27b1-mediated formation and stimulating Cyp24-mediated catabolism of 1,25(OH)2D. FGF23 participates in a new bone/kidney axis that protects the organism from excess vitamin D and coordinates renal PO43−handling with bone mineralization/turnover. Abnormalities of FGF23 production underlie many inherited and acquired disorders of phosphate homeostasis. This review discusses the known and emerging functions of FGF23, its regulation in response to systemic and local signals, as well as the implications of FGF23 in different pathological and physiological contexts.
Cellular and Molecular Specificity of Pituitary Gland Physiology
Authors: Perez-Castro Carolina , Renner Ulrich , Haedo Mariana R. , Stalla Gunter K. , Arzt Eduardo
Published: February 2012

The anterior pituitary gland has the ability to respond to complex signals derived from central and peripheral systems. Perception of these signals and their integration are mediated by cell interactions and cross-talk of multiple signaling transduction pathways and transcriptional regulatory networks that cooperate for hormone secretion, cell plasticity, and ultimately specific pituitary responses that are essential for an appropriate physiological response. We discuss the physiopathological and molecular mechanisms related to this integrative regulatory system of the anterior pituitary gland and how it contributes to modulate the gland functions and impacts on body homeostasis.
Physical Activity and Exercise in the Regulation of Human Adipose Tissue Physiology
Authors: Thompson Dylan , Karpe Fredrik , Lafontan Max , Frayn Keith
Published: February 2012

Physical activity and exercise are key components of energy expenditure and therefore of energy balance. Changes in energy balance alter fat mass. It is therefore reasonable to ask: What are the links between physical activity and adipose tissue function? There are many complexities. Physical activity is a multifaceted behavior of which exercise is just one component. Physical activity influences adipose tissue both acutely and in the longer term. A single bout of exercise stimulates adipose tissue blood flow and fat mobilization, resulting in delivery of fatty acids to skeletal muscles at a rate well-matched to metabolic requirements, except perhaps in vigorous intensity exercise. The stimuli include adrenergic and other circulating factors. There is a period following an exercise bout when fatty acids are directed away from adipose tissue to other tissues such as skeletal muscle, reducing dietary fat storage in adipose. With chronic exercise (training), there are changes in adipose tissue physiology, particularly an enhanced fat mobilization during acute exercise. It is difficult, however, to distinguish chronic “structural” changes from those associated with the last exercise bout. In addition, it is difficult to distinguish between the effects of training per se and negative energy balance. Epidemiological observations support the idea that physically active people have relatively low fat mass, and intervention studies tend to show that exercise training reduces fat mass. A much-discussed effect of exercise versus calorie restriction in preferentially reducing visceral fat is not borne out by meta-analyses. We conclude that, in addition to the regulation of fat mass, physical activity may contribute to metabolic health through beneficial dynamic changes within adipose tissue in response to each activity bout.
Modelling the Implications of Quality Management Elements on Strategic Flexibility
Authors: Escrig-Tena Ana Belén , Bou-Llusar Juan Carlos , Beltrán-Martín Inmaculada , Roca-Puig Vicente
Published: February 2012

This paper presents a theoretical and empirical analysis of the implications of a quality management (QM) initiative on strategic flexibility. Our study defines flexibility from a strategic approach and examines the extent to which, why, and how the triggering factors of strategic flexibility are related to QM elements. The hypotheses put forward are tested in an empirical study carried out on a sample of Spanish firms, using structural equation models. The results demonstrate the positive effect of adopting an integral QM initiative on enhancing strategic flexibility. QM enhances strategic flexibility more effectively when it is introduced comprehensively rather than in a piecemeal fashion. A series of practices linked to the application of a QM initiative are outlined, which managers can use to improve strategic flexibility. The approach used in the study can be applied to analyse other antecedents of flexibility and to propose possible studies that consider QM as an antecedent of other organisational variables.
Fatty Acid Oxidation and Cardiovascular Risk during Menopause: A Mitochondrial Connection?
Authors: Oliveira Paulo J. , Carvalho Rui A. , Portincasa Piero , Bonfrate Leonilde , Sardao Vilma A.
Published: February 2012

Menopause is a consequence of the normal aging process in women. This fact implies that the physiological and biochemical alterations resulting from menopause often blur with those from the aging process. It is thought that menopause in women presents a higher risk for cardiovascular disease although the precise mechanism is still under discussion. The postmenopause lipid profile is clearly altered, which can present a risk factor for cardiovascular disease. Due to the role of mitochondria in fatty acid oxidation, alterations of the lipid profile in the menopausal women will also influence mitochondrial fatty acid oxidation fluxes in several organs. In this paper, we propose that alterations of mitochondrial bioenergetics in the heart, consequence from normal aging and/or from the menopausal process, result in decreased fatty acid oxidation and accumulation of fatty acid intermediates in the cardiomyocyte cytosol, resulting in lipotoxicity and increasing the cardiovascular risk in the menopausal women.
Orbital Myiasis: Due to Invasion of Larvae of Flesh Fly (Wohlfahrtia magnifica) in a Child; Rare Presentation
Authors: Maurya R. P. , Mishra Deepak , Bhushan Prashant , Singh V. P. , Singh M. K.
Published: February 2012

Wohlfahrtia magnificalarvae cause myiasis in mammals, mainly in sheep and rarely in human. In humanitmay infest the ear, eye, mouth or nose, damaging living tissues. We report a case of ocular myiasis in 1.5 years old child belonging to urban slum after history of minor injury on left upper lid due to fall from bed. The purpose of reporting this case is to highlight the ocular association ofW. magnifica.
Potential Antioxidant Role of Tridham in Managing Oxidative Stress against Aflatoxin-B1-Induced Experimental Hepatocellular Carcinoma
Authors: Ravinayagam Vijaya , Jaganathan Ravindran , Panchanadham Sachdanandam , Palanivelu Shanthi
Published: February 2012

Hepatocellular carcinoma (HCC) is one of the most fatal cancers due to delayed diagnosis and lack of effective treatment options. Significant exposure to Aflatoxin B1(AFB1), a potent hepatotoxic and hepatocarcinogenic mycotoxin, plays a major role in liver carcinogenesis through oxidative tissue damage and p53 mutation. The present study emphasizes the anticarcinogenic effect of Tridham (TD), a polyherbal traditional medicine, on AFB1-induced HCC in male Wistar rats. AFB1-administered HCC-bearing rats (Group II) showed increased levels of lipid peroxides (LPOs), thiobarbituric acid substances (TBARs), and protein carbonyls (PCOs) and decreased levels of enzymic and nonenzymic antioxidants when compared to control animals (Group I). Administration of TD orally (300 mg/kg body weight/day) for 45 days to HCC-bearing animals (Group III) significantly reduced the tissue damage accompanied by restoration of the levels of antioxidants. Histological observation confirmed the induction of tumour in Group II animals and complete regression of tumour in Group III animals. This study highlights the potent antioxidant properties of TD which contribute to its therapeutic effect in AFB1-induced HCC in rats.
Potential Operators on Cones of Nonincreasing Functions
Authors: Meskhi Alexander , Murtaza Ghulam
Published: February 2012

Necessary and sufficient conditions on weight pairs guaranteeing the two-weight inequalities for the potential operators(Iαf)(x)=∫0∞(f(t)/|x−t|1−α)dtand(ℐα1,α2f)(x,y)=∫0∞∫0∞(f(t,τ)/|x−t|1−α1|y−τ|1−α2)dtdτon the cone of nonincreasing functions are derived. In the case ofℐα1,α2, we assume that the right-hand side weight is of product type. The same problem for other mixed-type double potential operators is also studied. Exponents of the Lebesgue spaces are assumed to be between 1 and ∞.
New Insights into the Immunological Changes in IL-10-Deficient Mice during the Course of Spontaneous Inflammation in the Gut Mucosa
Authors: Gomes-Santos Ana Cristina , Moreira Thais Garcias , Castro-Junior Archimedes Barbosa , Horta Bernardo Coelho , Lemos Luisa , Cruz Deborah Nogueira , Guimarães Mauro Andrade Freitas , Cara Denise Carmona , McCafferty Donna-Marie , Faria Ana Maria Caetano
Published: February 2012

IL-10 is a regulatory cytokine that plays a major role in the homeostasis of the gut and this is illustrated by the fact that IL-10−/−mice develop spontaneous colitis. In this study, IL-10−/−mice were analyzed for immunological changes during colitis development. We found a reduced frequency of regulatory T cellsCD4+CD25+Foxp3+and higher frequency of activated T cells in the colon that precedes the macroscopic signs of the disease. Production of IL-17 and IFN-γ was higher in the colon. Colitis progression culminates with the reduction ofCD4+LAP+regulatory T cells in the intestine. Frequency of B1 cells and the secretory IgA production were both elevated. Despite these alterations, 16-week-old IL-10−/−mice could be rendered tolerant by a continuous feeding protocol. Our study provides detailed analysis of changes that precede colitis and it also suggests that oral tolerance could be used to design novel alternative therapies for the disease.
Thymus Atrophy and Double-Positive Escape Are Common Features in Infectious Diseases
Authors: de Meis Juliana , Aurélio Farias-de-Oliveira Désio , Nunes Panzenhagen Pedro H. , Maran Naiara , Villa-Verde Déa Maria Serra , Morrot Alexandre , Savino Wilson
Published: February 2012

The thymus is a primary lymphoid organ in which bone marrow-derived T-cell precursors undergo differentiation, leading to migration of positively selected thymocytes to the T-cell-dependent areas of secondary lymphoid organs. This organ can undergo atrophy, caused by several endogenous and exogenous factors such as ageing, hormone fluctuations, and infectious agents. This paper will focus on emerging data on the thymic atrophy caused by infectious agents. We present data on the dynamics of thymus lymphocytes during acuteTrypanosoma cruziinfection, showing that the resulting thymus atrophy comprises the abnormal release of thymic-derived T cells and may have an impact on host immune response.
Synchronization of Complex Networks with Time‐Varying Delayed Dynamical Nodes via Pinning Control
Authors: Wang Shuguo , Yao Hongxing , Bian Qiuxiang
Published: February 2012

This paper investigates the pinning synchronization of nonlinearly coupled complex networks with time‐varying coupling delay and time‐varying delay in dynamical nodes. Some simple and useful criteria are derived by constructing an effective control scheme and adjusting automatically the adaptive coupling strengths. To validate the proposed method, numerical simulation examples are provided to verify the correctness and effectiveness of the proposed scheme.
Intake of Nutritional Supplements among People Exercising in Gyms in Beirut City
Authors: El Khoury D. , Antoine-Jonville S.
Published: February 2012

The use of nutritional supplements among exercisers in gyms has been never investigated in the Middle East. The aim of the current study was to assess the prevalence intake of nutritional supplements and the potential influencing factors among people exercising in gyms in Beirut city. In this cross-sectional study, 512 exercisers, aged between 20 and 50 years, were randomly selected from gyms. The intake of nutritional supplements was reported among 36.3% (95% confidence interval 32.2–40.5) of participants, with a weak presence of medical supervision. Patterns of supplement use differed by gender and age. Men and younger exercisers were found to focus on supplements associated with performance enhancement and muscle building, while women and older exercisers were more concerned with health-promoting products such as vitamins, minerals, and herbal supplements. An appropriate dissemination of accurate and scientifically sound information regarding the benefits and side effects of nutritional supplements is highly recommended in the sports environment in Beirut city.
Pleural Fluid Analysis: Standstill or a Work in Progress?
Authors: Hassan T. , Al-Alawi M. , Chotirmall S. H. , McElvaney N. G.
Published: February 2012

Pleural fluid analysis yields important diagnostic information in pleural effusions in combination with clinical history, examination, and radiology. For more than 30 years, the initial and most pragmatic step in this process is to determine whether the fluid is a transudate or an exudate. Light's criteria remain the most robust in separating the transudate-exudate classification which dictates further investigations or management. Recent studies have led to the evaluation and implementation of a number of additional fluid analyses that may improve the diagnostic utility of this method. This paper discusses the current practice and future direction of pleural fluid analysis in determining the aetiology of a pleural effusion. While this has been performed for a few decades, a number of other pleural characteristics are becoming available suggesting that this diagnostic tool is indeed a work in progress.
Zuonin B Inhibits Lipopolysaccharide-Induced Inflammation via Downregulation of the ERK1/2 and JNK Pathways in RAW264.7 Macrophages
Authors: Lee Mee-Young , Yuk Ji-Eun , Kwon Ok-Kyung , Oh Sei-Ryang , Lee Hyeong-Kyu , Ahn Kyung-Seop
Published: February 2012

We investigated whether Zuonin B exerts immunological effects on RAW264.7 cells. Zuonin B, isolated from flower buds ofDaphne genkwa, suppressed the levels of nitric oxide and prostaglandin E2, as well as proinflammatory cytokines, such as tumor necrosis factor-αand interleukin-(IL-) 6, in lipopolysaccharide-stimulated macrophages. Moreover, the compound inhibited cyclooxygenase-2 and inducible nitric oxide synthase expression. Zuonin B attenuated NF-kappaB (NF-κB) activation via suppressing proteolysis of inhibitor kappa B-alpha (IκB-α) and p65 nuclear translocation as well as phosphorylation of extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase. Additionally, IL-4 and IL-13 production in ConA-induced splenocytes was inhibited by Zuonin B. In conclusion, the anti-inflammatory effects of Zuonin B are attributable to the suppression of proinflammatory cytokines and mediators via blockage of NF-κB and AP-1 activation. Based on these findings, we propose that Zuonin B is potentially an effective functional chemical candidate for the prevention of inflammatory diseases.
On Stochastic Finite‐Time Control of Discrete‐Time Fuzzy Systems with Packet Dropout
Authors: Zhang Yingqi , Liu Caixia , Mu Xiaowu
Published: February 2012

This paper is concerned with the stochastic finite‐time stability and stochastic finite‐time boundedness problems for one family of fuzzy discrete‐time systems over networks with packet dropout, parametric uncertainties, and time‐varying norm‐bounded disturbance. Firstly, we present the dynamic model description studied, in which the discrete‐time fuzzy T‐S systems with packet loss can be described by one class of fuzzy Markovian jump systems. Then, the concepts of stochastic finite‐time stability and stochastic finite‐time boundedness and problem formulation are given. Based on Lyapunov function approach, sufficient conditions on stochastic finite‐time stability and stochastic finite‐time boundedness are established for the resulting closed‐loop fuzzy discrete‐time system with Markovian jumps, and state‐feedback controllers are designed to ensure stochastic finite‐time stability and stochastic finite‐time boundedness of the class of fuzzy systems. The stochastic finite‐time stability and stochastic finite‐time boundedness criteria can be tackled in the form of linear matrix inequalities with a fixed parameter. As an auxiliary result, we also give sufficient conditions on the stochastic stability of the class of fuzzy T‐S systems with packet loss. Finally, two illustrative examples are presented to show the validity of the developed methodology.
Peroxisome Proliferator-Activated Receptor-γ-Mediated Polarization of Macrophages inLeishmaniaInfection
Authors: Chan Marion M. , Adapala Nagasuresh , Chen Cui
Published: February 2012

Infection is the outcome of a contest between a pathogen and its host. In the disease leishmaniasis, the causative protozoan parasites are harbored inside the macrophages.Leishmaniaspecies adapt strategies to make the infection chronic, keeping a balance between their own and the host's defense so as to establish an environment that is favorable for survival and propagation. Activation of peroxisome proliferator-activated receptor (PPAR) is one of the tactics used. This ligand-activated nuclear factor curbs inflammation to protect the host from excessive injuries by setting a limit to its destructive force. In this paper, we report the interaction of host PPARs and the pathogen for visceral leishmaniasis,Leishmania donovani,in vivoandin vitro. PPAR expression is induced by parasitic infection. Leishmanial activation of PPARγpromotes survival, whereas blockade of PPARγfacilitates removal of the parasite. Thus,Leishmaniaparasites harness PPARγto increase infectivity.
Cortical Surface Reconstruction from High-Resolution MR Brain Images
Authors: Osechinskiy Sergey , Kruggel Frithjof
Published: February 2012

Reconstruction of the cerebral cortex from magnetic resonance (MR) images is an important step in quantitative analysis of the human brain structure, for example, in sulcal morphometry and in studies of cortical thickness. Existing cortical reconstruction approaches are typically optimized for standard resolution (~1 mm) data and are not directly applicable to higher resolution images. A new PDE-based method is presented for the automated cortical reconstruction that is computationally efficient and scales well with grid resolution, and thus is particularly suitable for high-resolution MR images with submillimeter voxel size. The method uses a mathematical model of a field in an inhomogeneous dielectric. This field mapping, similarly to a Laplacian mapping, has nice laminar properties in the cortical layer, and helps to identify the unresolved boundaries between cortical banks in narrow sulci. The pial cortical surface is reconstructed by advection along the field gradient as a geometric deformable model constrained by topology-preserving level set approach. The method’s performance is illustrated on exvivo images with 0.25–0.35 mm isotropic voxels. The method is further evaluated by cross-comparison with results of the FreeSurfer software on standard resolution data sets from the OASIS database featuring pairs of repeated scans for 20 healthy young subjects.
Sef Downregulation by Ras Causes MEK1/2 to Become Aberrantly Nuclear Localized Leading to Polyploidy and Neoplastic Transformation
Authors: Duhamel Stéphanie , Hébert Josée , Gaboury Louis , Bouchard Amélie , Simon Ronald , Sauter Guido , Basik Mark , Meloche Sylvain
Published: February 2012

Subcellular trafficking of key oncogenic signal pathway components is likely to be crucial for neoplastic transformation, but little is known about how such trafficking processes are spatially controlled. In this study, we show how Ras activation causes aberrant nuclear localization of phosphorylated mitogen-activated protein (MAP)/extracellular signal-regulated kinase (ERK; MEK) MEK1/2 to drive neoplastic transformation. Phosphorylated MEK1/2 was aberrantly located within the nucleus of primary colorectal tumors and human colon cancer cells, and oncogenic activation of Ras was sufficient to induce nuclear accumulation of phosphorylated MEK1/2 and ERK1/2 in intestinal epithelial cells. Enforced nuclear localization of MEK1 in epithelial cells or fibroblasts was sufficient for hyperactivation of ERK1/2, thereby driving cell proliferation, chromosomal polyploidy, and tumorigenesis. Notably, Ras-induced nuclear accumulation of activated MEK1/2 was reliant on downregulation of the spatial regulator Sef, the reexpression of which was sufficient to restore normal MEK1/2 localization and a reversal of Ras-induced proliferation and tumorigenesis. Taken together, our findings indicate that Ras-induced downregulation of Sef is an early oncogenic event that contributes to genetic instability and tumor progression by sustaining nuclear ERK1/2 signaling. Cancer Res; 72(3); 626–35. ©2012 AACR.
Reports from the 2010 Clinical and Translational Cancer Research Think Tank Meeting: Design Strategies for Personalized Therapy Trials
Authors: Berry Donald A. , Herbst Roy S. , Rubin Eric H.
Published: February 2012

It has long been evident that cancer is a heterogeneous disease, but only relatively recently have we come to realize the extent of this heterogeneity. No single therapy is effective for every patient with tumors having the same histology. A clinical strategy based on a single-therapy approach results in overtreatment for the majority of patients. Biomarkers can be considered as knives that dissect the disease ever more finely. The future of clinical research will be based on learning whether certain therapies are more appropriate than others for biomarker-defined subsets of patients. Therapies will eventually be tailored to narrow biomarker subsets. The ability to determine which therapies are appropriate for which patients requires information from biological science as well as empirical evidence from clinical trials. Neither is easy to achieve. Here we describe some nascent approaches for designing clinical trials that are biomarker-based and adaptive. Our focus is on adaptive trials that address many questions at once. In a way, these clinical experiments are themselves part of a much larger experiment: learning how (or whether it is possible) to design experiments that match patients in small subsets of disease with therapies that are especially effective and possibly even curative for them. Clin Cancer Res; 18(3); 638–44. ©2012 AACR.
Imaging: Strategies, Controversies, and Opportunities
Authors: Blasberg Ronald , Piwnica-Worms David
Published: February 2012

At a Clinical and Translational Cancer Research Think Tank meeting sponsored by the American Association for Cancer Research in 2010, one of the breakout groups focused on new technologies and imaging. The discussions emphasized new opportunities in translational imaging and its role in the future, rather than established techniques that are currently in clinical practice. New imaging methods under development are changing the approach of imaging science from a focus on the anatomic description of disease to a focus on the molecular basis of disease. Broadly referred to as molecular imaging, these new strategies directly embrace the incorporation of cell and molecular biology concepts and techniques into image generation and can involve the introduction of genes into cells with the explicit intent to image the end products of gene expression with external imaging devices. These new methods hold the promise of providing clinicians with (i) robust linkages between cell and animal models and clinical trials, (ii) in vivo biomarkers that can be measured repeatedly and sequentially over time to observe dynamic disease processes and responses to treatment, and (iii) tools for preselection and patient population enrichment in phase II and III trials to improve outcomes and better direct treatment. These strategies provide real-time pharmacodynamic parameters and can be powerful tools to monitor therapeutic effects in a spatially and tissue-specific manner, which may reduce cost during drug development, because pharmacodynamic studies in animals can inform clinical trials and accelerate the translation process. The Imaging Response Assessment Team (IRAT) program serves as an example of how imaging techniques can be incorporated into clinical trials. IRATs work to advance the role of imaging in assessment of response to therapy and to increase the application of quantitative anatomic, functional, and molecular imaging endpoints in clinical trials, and imaging strategies that will lead to individualized patient care. Clin Cancer Res; 18(3); 631–7. ©2012 AACR.
Genetically Modified Mouse Models for Biomarker Discovery and Preclinical Drug Testing
Authors: Kucherlapati Raju
Published: February 2012

The ability to grow pluripotent mouse embryonic stem cells in culture, and to introduce precise genetic modifications into those cells through gene targeting, has greatly facilitated the generation of mouse models of human disease. This technology is playing a particularly important role in cancer research. In addition to their use in elucidating the role of individual genes or combinations of 2 or more genes, the genetically engineered mouse models are being used to develop biomarkers and for preclinical drug testing. By examining plasma samples from tumor-bearing mice from mice carrying specific mutations in tumor suppressor genes and/or oncogenes, investigators can identify tumor-specific biomarkers that are overexpressed in the tumor cells. These markers are directly relevant to the corresponding human cancer. The ability to generate tumors at the correct anatomical site within the normal cellular environment is augmenting the use of xenografts in drug testing in a preclinical setting. Clin Cancer Res; 18(3); 625–30. ©2012 AACR.