bluuebunny/crossref_metadata_2025 huggingface dataset:
Fundus Autofluorescence and Optical Coherence Tomography Findings in Branch Retinal Vein Occlusion
Authors: Sekiryu Tetsuju , Iida Tomohiro , Sakai Eiichi , Maruko Ichiro , Ojima Akira , Sugano Yukinori
Published: November 2012

Purpose. To describe the findings of fundus autofluorescence (FAF) and optical coherence tomography (OCT) in patients with branch retinal vein occlusion (BRVO).Methods. In this institutional, retrospective, observational case series, FAF was evaluated in 65 eyes with BRVO in 64 consecutive patients and compared with visual acuity, OCT findings, and other clinical observations.Results. Five types of autofluorescence appeared during the course of BRVO: (1) petaloid-shaped hyperautofluorescence in the area of macular edema and (2) hyperautofluorescence coincident with yellow subretinal deposits. (3) Diffuse hyperautofluorescence appeared within the area of serous retinal detachment (SRD) and OCT showed precipitates on the undersurface of the retina in 5/5 of these eyes (100%). (4) The area of vein occlusion showed diffuse hyperautofluorescence after resolution of the retinal bleeding. (5) Hard exudates exhibited hyper- or hypoautofluorescence. OCT indicated that most of the hard exudates with hyperautofluorescence were located on the retinal pigment epithelium.Conclusions. Hyperautofluorescence associated with subretinal fluid or hard exudate appeared in the subretinal space. This type of hyperautofluorescence may be attributed to blood cell or macrophages. FAF and OCT are noninvasive modalities that provide additional information regarding macular edema due to BRVO.
Downregulation of Oxidative and Nitrosative Apoptotic Signaling by L-Carnitine in Ifosfamide-Induced Fanconi Syndrome Rat Model
Authors: Sayed-Ahmed Mohamed M. , Hafez Mohamed M. , Aldelemy Meshan Lafi , Aleisa Abdulaziz M. , Al-Rejaie Salem S. , Al-Hosaini Khaled A. , Al-Harbi Naif O. , Al-Harbi Mohamed M. , Al-Shabanah Othman A.
Published: November 2012

It is well documented that ifosfamide (IFO) therapy is associated with sever nephropathy in the form of Fanconi syndrome. Although oxidative stress has been reported as a major player in IFO-induced Fanconi syndrome, no mechanism for this effect has been ascertained. Therefore, this study has been initiated to investigate, on gene expression level, the mechanism of IFO-induce nephrotoxicity and those whereby carnitine supplementation attenuates this serious side effect of IFO. To achieve the ultimate goals of this study, adult male rats were assigned to one of four treatment groups, namely, control, L-carnitine, IFO, and IFO plus L-carnitine. Administration of IFO for 5 days significantly increased serum creatinine, blood urea nitrogen (BUN), and total nitrate/nitrite (NOx) production in kidney tissues. In addition, IFO significantly increased mRNA expression of inducible nitric oxide synthase (iNOS), caspase-9, and caspase-3 and significantly decreased expression of glutathione peroxides (GPx), catalase (CAT), and Bcl2 in kidney tissues. Administration of L-carnitine to IFO-treated rats resulted in a complete reversal of the all biochemical and gene expression changes, induced by IFO, to the control values. Data from this study suggest that L-carnitine prevents the development of IFO-induced nephrotoxicity via downregulation of oxidative and nitrosative apoptotic signaling in kidney tissues.
Pneumatosis Intestinalis: Not Always a Surgical Indication
Authors: Zhang Haijing , Jun Stephanie L. , Brennan Todd V.
Published: November 2012

We present a case of pneumatosis intestinalis (PI) of the colon in the setting of inflammatory bowel disease that was treated with medical management rather than emergent surgery. While the reflex response to extraluminal air in the abdomen is abdominal exploration, consideration of the clinical context in which PI is discovered and an understanding of a complete differential diagnosis of the sources of PI is critical to avoiding unnecessary surgery.
Melanogenesis Inhibitor(s) fromPhyla nodifloraExtract
Authors: Yen Feng-Lin , Wang Moo-Chin , Liang Chan-Jung , Ko Horng-Huey , Lee Chiang-Wen
Published: November 2012

Overexpression of tyrosinase can cause excessive production of melanin and lead to hyperpigmentation disorders, including melasma and freckles. Recently, agents obtained from plants are being used as alternative medicines to downregulate tyrosinase synthesis and decrease melanin production.Phyla nodifloraGreene (Verbenaceae) is used as a folk medicine in Taiwanese for treating and preventing inflammatory diseases such as hepatitis and dermatitis. However, the antimelanogenesis activity and molecular biological mechanism underlying the activity of the methanolic extract ofP. nodiflora(PNM) have not been investigated to date. Our results showed that PNM treatment was not cytotoxic and significantly reduced the cellular melanin content and tyrosinase activity in a dose-dependent manner (P<0.05). Further, PNM exhibited a significant antimelanogenesis effect (P<0.05) by reducing the levels of phospho-cAMP response element-binding protein and microphthalmia-associated transcription factor (MITF), inhibiting the synthesis of tyrosinase, tyrosinase-related protein-1 (TRP-1), and TRP-2, and decreasing the cellular melanin content. Moreover, PNM significantly activated the phosphorylation of mitogen-activated protein kinases, including phospho-extracellular signal-regulated kinase, c-Jun N-terminal kinase, and phospho-p38, and inhibited the synthesis of MITF, thus decreasing melanogenesis. These properties suggest that PNM could be used as a clinical and cosmetic skin-whitening agent to cure and/or prevent hyperpigmentation.
Oncoplastic Breast Reduction: Maximizing Aesthetics and Surgical Margins
Authors: Chang Michelle Milee , Huston Tara , Ascherman Jeffrey , Rohde Christine
Published: November 2012

Oncoplastic breast reduction combines oncologically sound concepts of cancer removal with aesthetically maximized approaches for breast reduction. Numerous incision patterns and types of pedicles can be used for purposes of oncoplastic reduction, each tailored for size and location of tumor. A team approach between reconstructive and breast surgeons produces positive long-term oncologic results as well as satisfactory cosmetic and functional outcomes, rendering oncoplastic breast reduction a favorable treatment option for certain patients with breast cancer.
Cellular Signal Mechanisms of Reward-Related Plasticity in the Hippocampus
Authors: Isokawa Masako
Published: November 2012

The hippocampus has the extraordinary capacity to process and store information. Consequently, there is an intense interest in the mechanisms that underline learning and memory. Synaptic plasticity has been hypothesized to be the neuronal substrate for learning. Ca2+and Ca2+-activated kinases control cellular processes of most forms of hippocampal synapse plasticity. In this paper, I aim to integrate our current understanding of Ca2+-mediated synaptic plasticity and metaplasticity in motivational and reward-related learning in the hippocampus. I will introduce two representative neuromodulators that are widely studied in reward-related learning (e.g., ghrelin and endocannabinoids) and show how they might contribute to hippocampal neuron activities and Ca2+-mediated signaling processes in synaptic plasticity. Additionally, I will discuss functional significance of these two systems and their signaling pathways for its relevance to maladaptive reward learning leading to addiction.
Fourier Analysis of Slow and Fast Image Propagation through Single and Coupled Image Resonators
Authors: Sultana Parvin , Matsumoto Takahiro , Tomita Makoto
Published: November 2012

We applied Fourier space analysis to a comprehensive study of the propagation of pulsed two-dimensional images through single and coupled image resonators. The Fourier method shows that the image can propagate through the resonator successfully as long as the spatial and temporal Fourier components of the image are within the bandwidth of the amplitude and phase transfer functions. The relevant steep dispersion of the cavity can yield delayed or advanced images. The Fourier method reproduces characteristic aspects of the experimental observations of the image propagation, and also predicts new aspects, such as the spatial image profile dependence on the observation time and the coupling strength. To demonstrate the time evolution of the experiment, space- and time-resolved image propagations were performed using a streak camera.
A Novel HLA-A*0201 Restricted Peptide Derived from Cathepsin G Is an Effective Immunotherapeutic Target in Acute Myeloid Leukemia
Authors: Zhang Mao , Sukhumalchandra Pariya , Enyenihi Atim A. , St. John Lisa S. , Hunsucker Sally A. , Mittendorf Elizabeth A. , Sergeeva Anna , Ruisaard Kathryn , Al-Atrache Zein , Ropp Patricia A. , Jakher Haroon , Rodriguez-Cruz Tania , Lizee Gregory , Clise-Dwyer Karen , Lu Sijie , Molldrem Jeffrey J. , Glish Gary L. , Armistead Paul M. , Alatrash Gheath
Published: November 2012

Purpose: Immunotherapy targeting aberrantly expressed leukemia-associated antigens has shown promise in the management of acute myeloid leukemia (AML). However, because of the heterogeneity and clonal evolution that is a feature of myeloid leukemia, targeting single peptide epitopes has had limited success, highlighting the need for novel antigen discovery. In this study, we characterize the role of the myeloid azurophil granule protease cathepsin G (CG) as a novel target for AML immunotherapy.

Experimental Design: We used Immune Epitope Database and in vitro binding assays to identify immunogenic epitopes derived from CG. Flow cytometry, immunoblotting, and confocal microscopy were used to characterize the expression and processing of CG in AML patient samples, leukemia stem cells, and normal neutrophils. Cytotoxicity assays determined the susceptibility of AML to CG-specific cytotoxic T lymphocytes (CTL). Dextramer staining and cytokine flow cytometry were conducted to characterize the immune response to CG in patients.

Results: CG was highly expressed and ubiquitinated in AML blasts, and was localized outside granules in compartments that facilitate antigen presentation. We identified five HLA-A*0201 binding nonameric peptides (CG1-CG5) derived from CG, and showed immunogenicity of the highest HLA-A*0201 binding peptide, CG1. We showed killing of primary AML by CG1-CTL, but not normal bone marrow. Blocking HLA-A*0201 abrogated CG1-CTL–mediated cytotoxicity, further confirming HLA-A*0201-dependent killing. Finally, we showed functional CG1-CTLs in peripheral blood from AML patients following allogeneic stem cell transplantation.

Conclusion: CG is aberrantly expressed and processed in AML and is a novel immunotherapeutic target that warrants further development. Clin Cancer Res; 19(1); 247–57. ©2012 AACR.
Circulation
Editors' Picks
Authors:   The Editors
Published: November 2012

The following articles are being highlighted as part of
Circulation's
Topic Review series. This series will summarize the most important manuscripts, as selected by the editors, published in
Circulation
and the
Circulation
subspecialty journals. The studies included in this article represent the most read manuscripts published on the topic of cardiovascular clinical trials within the last year.
Going to the Roots of Dependency Parsing
Authors: Ballesteros Miguel , Nivre Joakim
Published: November 2012

Dependency trees used in syntactic parsing often include a root node representing a dummy word prefixed or suffixed to the sentence, a device that is generally considered a mere technical convenience and is tacitly assumed to have no impact on empirical results. We demonstrate that this assumption is false and that the accuracy of data-driven dependency parsers can in fact be sensitive to the existence and placement of the dummy root node. In particular, we show that a greedy, left-to-right, arc-eager transition-based parser consistently performs worse when the dummy root node is placed at the beginning of the sentence (following the current convention in data-driven dependency parsing) than when it is placed at the end or omitted completely. Control experiments with an arc-standard transition-based parser and an arc-factored graphbased parser reveal no consistent preferences but nevertheless exhibit considerable variation in results depending on root placement. We conclude that the treatment of dummy root nodes in data-driven dependency parsing is an underestimated source of variation in experiments andmay also be a parameter worth tuning for some parsers.
Dynamical Movement Primitives: Learning Attractor Models for Motor Behaviors
Authors: Ijspeert Auke Jan , Nakanishi Jun , Hoffmann Heiko , Pastor Peter , Schaal Stefan
Published: November 2012

Nonlinear dynamical systems have been used in many disciplines to model complex behaviors, including biological motor control, robotics, perception, economics, traffic prediction, and neuroscience. While often the unexpected emergent behavior of nonlinear systems is the focus of investigations, it is of equal importance to create goal-directed behavior (e.g., stable locomotion from a system of coupled oscillators under perceptual guidance). Modeling goal-directed behavior with nonlinear systems is, however, rather difficult due to the parameter sensitivity of these systems, their complex phase transitions in response to subtle parameter changes, and the difficulty of analyzing and predicting their long-term behavior; intuition and time-consuming parameter tuning play a major role. This letter presents and reviews dynamical movement primitives, a line of research for modeling attractor behaviors of autonomous nonlinear dynamical systems with the help of statistical learning techniques. The essence of our approach is to start with a simple dynamical system, such as a set of linear differential equations, and transform those into a weakly nonlinear system with prescribed attractor dynamics by means of a learnable autonomous forcing term. Both point attractors and limit cycle attractors of almost arbitrary complexity can be generated. We explain the design principle of our approach and evaluate its properties in several example applications in motor control and robotics.
Enhanced Gradient for Training Restricted Boltzmann Machines
Authors: Cho KyungHyun , Raiko Tapani , Ilin Alexander
Published: November 2012

Restricted Boltzmann machines (RBMs) are often used as building blocks in greedy learning of deep networks. However, training this simple model can be laborious. Traditional learning algorithms often converge only with the right choice of metaparameters that specify, for example, learning rate scheduling and the scale of the initial weights. They are also sensitive to specific data representation. An equivalent RBM can be obtained by flipping some bits and changing the weights and biases accordingly, but traditional learning rules are not invariant to such transformations. Without careful tuning of these training settings, traditional algorithms can easily get stuck or even diverge. In this letter, we present an enhanced gradient that is derived to be invariant to bit-flipping transformations. We experimentally show that the enhanced gradient yields more stable training of RBMs both when used with a fixed learning rate and an adaptive one.
The Kernel Semi–Least Squares Method for Sparse Distance Approximation
Authors: Epstein Samuel , Betke Margrit
Published: November 2012

We extend the semi–least squares problem defined by Rao and Mitra ( 1971 ) to the kernel semi–least squares problem. We introduce subset projection, a technique that produces a solution to this problem. We show how the results of subset projection can be used to approximate a computationally expensive distance metric.
The Variability and Predictability of Axisymmetric Hurricanes in Statistical Equilibrium
Authors: Hakim Gregory J.
Published: November 2012

The variability and predictability of axisymmetric hurricanes are determined from a 500-day numerical simulation of a tropical cyclone in statistical equilibrium. By design, the solution is independent of the initial conditions and environmental variability, which isolates the “intrinsic” axisymmetric hurricane variability.

Variability near the radius of maximum wind is dominated by two patterns: one associated primarily with radial shifts of the maximum wind, and one primarily with intensity change at the time-mean radius of maximum wind. These patterns are linked to convective bands that originate more than 100 km from the storm center and propagate inward. Bands approaching the storm produce eyewall replacement cycles, with an increase in storm intensity as the secondary eyewall contracts radially inward. A dominant time period of 4–8 days is found for the convective bands, which is hypothesized to be determined by the time scale over which subsidence from previous bands suppresses convection; a leading-order estimate based on the ratio of the Rossby radius to band speed fits the hypothesis.

Predictability limits for the idealized axisymmetric solution are estimated from linear inverse modeling and analog forecasts, which yield consistent results showing a limit for the azimuthal wind of approximately 3 days. The optimal initial structure that excites the leading pattern of 24-h forecast-error variance has largest azimuthal wind in the midtroposphere outside the storm and a secondary maximum just outside the radius of maximum wind. Forecast errors grow by a factor of 24 near the radius of maximum wind.
Supersaturation and Diffusional Droplet Growth in Liquid Clouds
Authors: Pinsky M. , Mazin I. P. , Korolev A. , Khain A.
Published: November 2012

The process of collective diffusional growth of droplets in an adiabatic parcel ascending or descending with the constant vertical velocity is analyzed in the frame of the regular condensation approach. Closed equations for the evolution of liquid water content, droplet radius, and supersaturation are derived from the mass balance equation centered with respect to the adiabatic water content. The analytical expression for the maximum supersaturation formed near the cloud base is obtained here. Similar analytical expressions for the height and liquid water mixing ratio corresponding to the level where occurs have also been obtained. It is shown that all three variables , , and are linearly related to each other and all are proportional to , where w is the vertical velocity and N is the droplet number concentration. Universal solutions for supersaturation and liquid water mixing ratio are found here, which incorporates the dependence on vertical velocity, droplet concentration, temperature, and pressure into one dimensionless parameter. The actual solutions for and can be obtained from the universal solutions with the help of appropriate scaling factors described in this study. The results obtained in the frame of this study provide a new look at the nature of supersaturation formation in liquid clouds. Despite the fact that the study does not include a detailed treatment of the activation process, it is shown that this work can be useful for the parameterization of cloud microphysical processes in cloud models, especially for the parameterization of cloud condensation nuclei (CCN) activation.
Diabatic Heating Profiles in Recent Global Reanalyses
Authors: Ling Jian , Zhang Chidong
Published: November 2012

Diabatic heating profiles are extremely important to the atmospheric circulation in the tropics and therefore to the earth’s energy and hydrological cycles. However, their global structures are poorly known because of limited information from in situ observations. Some modern global reanalyses provide the temperature tendency from the physical processes. Their proper applications require an assessment of their accuracy and uncertainties. In this study, diabatic heating profiles from three recent global reanalyses [ECMWF Interim Re-Analysis (ERA-Interim), Climate Forecast System Reanalysis (CFSR), and Modern Era Retrospective Analysis for Research and Applications (MERRA)] are compared to those derived from currently available sounding observations in the tropics and to each other in the absence of the observations. Diabatic heating profiles produced by the reanalyses match well with those based on sounding observations only at some locations. The three reanalyses agree with each other better in the extratropics, where large-scale condensation dominates the precipitation process in data assimilation models, than in the tropics, where cumulus parameterization dominates. In the tropics, they only agree with each other in gross features, such as the contrast between the ITCZs over different oceans. Their largest disagreement is the number and level of heating peaks in the tropics. They may produce a single, double, or triple heating peak at a given location. It is argued that cumulus parameterization cannot be the sole source of the disagreement. Implications of such disagreement are discussed.
Representatives and Employment Rights Disputes: What Works and What Doesn’t?
Authors: Walker Bernard , Hamilton R.T.
Published: November 2012

Grievances continue to attract much public controversy, but amid the ongoing rhetoric, the research evidence is limited. The popular debate has centred largely on the actions of employers and employees. This study of grievance cases explores the factors that influence the progression of these disputes. The findings highlight the influential role of external representatives in either restoring relationships or escalating disputes. The nature of that influence is associated with three critical attributes of the representative: (a) their current relationships with others involved in the dispute; (b) the extent to which they seek to maintain relationships into the future; and (c) their competency in dispute-handling. While these attributes are largely related to individuals rather than roles, unions have unique potential for functioning as relationship managers and preserving employment relationships. The decline of unions, however, heightens the need for organizations to seek other improved ways of resolving disputes.
Portable upper extremity robotics is as efficacious as upper extremity rehabilitative therapy: a randomized controlled pilot trial
Authors: Page Stephen J , Hill Valerie , White Susan
Published: November 2012

Objective:

To compare the efficacy of a repetitive task-specific practice regimen integrating a portable, electromyography-controlled brace called the ‘Myomo’ versus usual care repetitive task-specific practice in subjects with chronic, moderate upper extremity impairment.

Subjects:

Sixteen subjects (7 males; mean age 57.0 ± 11.02 years; mean time post stroke 75.0 ± 87.63 months; 5 left-sided strokes) exhibiting chronic, stable, moderate upper extremity impairment.

Interventions:

Subjects were administered repetitive task-specific practice in which they participated in valued, functional tasks using their paretic upper extremities. Both groups were supervised by a therapist and were administered therapy targeting their paretic upper extremities that was 30 minutes in duration, occurring 3 days/week for eight weeks. One group participated in repetitive task-specific practice entirely while wearing the portable robotic, while the other performed the same activity regimen manually.

Main outcome measures:

The upper extremity Fugl-Meyer, Canadian Occupational Performance Measure and Stroke Impact Scale were administered on two occasions before intervention and once after intervention.

Results:

After intervention, groups exhibited nearly identical Fugl-Meyer score increases of ≈2.1 points; the group using robotics exhibited larger score changes on all but one of the Canadian Occupational Performance Measure and Stroke Impact Scale subscales, including a 12.5-point increase on the Stroke Impact Scale recovery subscale.

Conclusions:

Findings suggest that therapist-supervised repetitive task-specific practice integrating robotics is as efficacious as manual practice in subjects with moderate upper extremity impairment.
The locus of flicker adaptation in the migraine visual system: A dichoptic study
Authors: Thabet Michel , Wilkinson Frances , Wilson Hugh R , Karanovic Olivera
Published: November 2012

Background

Flickering light has been shown to sensitize the migraine visual system at high stimulus contrast while elevating thresholds at low contrast. The present study employs a dichoptic psychophysical paradigm to ask whether the abnormal adaptation to flicker in migraine occurs before or after the binocular combination of inputs from the two eyes in the visual cortex.

Methods

Following adaptation to high contrast flicker presented to one eye only, flicker contrast increment thresholds were measured in each eye separately using dichoptic viewing.

Results

Modest interocular transfer of adaptation was seen in both migraine and control groups at low contrast. Sensitization at high contrast in migraine relative to control participants was seen in the adapted eye only, and an unanticipated threshold elevation occurred in the non-adapted eye. Migraineurs also showed significantly lower aversion thresholds to full field flicker than control participants, but aversion scores and increment thresholds were not correlated.

Conclusions

The results are simulated with a three-stage neural model of adaptation that points to strong adaptation at monocular sites prior to binocular combination, and weaker adaptation at the level of cortical binocular neurons. The sensitization at high contrast in migraine is proposed to result from stronger adaptation of inhibitory neurons, which act as a monocular normalization pool.
Types of Minority Discrimination and Terrorism
Authors: Piazza James A.
Published: November 2012

Qualitative research suggests that discrimination against minority groups precipitates terrorism in countries. This study adds to this body of research by determining which specific manifestations of minority discrimination—political, socioeconomic or cultural—are important and substantive predictors of terrorist activity. To do so, I conduct a series of negative binomial estimations and substantive effects simulations on a cross-national dataset of terrorist attacks and the treatment of minority groups in four specific areas: political participation and representation, economic status, religious and language rights. The results indicate that socioeconomic discrimination against minorities is the only consistently significant and highly substantive predictor of terrorism. The study concludes by discussing the implications of these findings to the scholarly literature on terrorism.
Sharing the Wealth
Authors: Binningsbø Helga Malmin , Rustad Siri Aas
Published: November 2012

This article critically examines the notion that wealth sharing in the aftermath of internal armed conflicts can bring about long-lasting peace. While wealth sharing is increasingly considered a crucial element of peacebuilding, the evidence concerning its success is inconclusive. Previous studies unfortunately suffer from weak theoretical and empirical definitions of wealth sharing and from examining only a subset of postconflict societies. This article improves the research by disaggregating the concept of wealth sharing to concrete policy relevant natural resource management tools and by introducing new and better data on wealth sharing and including more postconflict peace periods than previous studies. This article examines the relationships between armed conflict, wealth sharing and peace by studying two independent but interlinked research questions: In which postconflict societies is wealth sharing most likely to be adopted? And can wealth sharing bring stable peace in postconflict societies? The analyses show that wealth sharing is more likely to be implemented after natural resource conflicts. Nonetheless, the article does not find that wealth sharing is successful in bringing postconflict peace after these conflicts. Reasons for this can be that (1) other factors than wealth sharing explain the outcome better, and (2) the wealth sharing policies are poorly designed and implemented. The article concludes that wealth sharing can only be a suitable path for societies recovering from armed conflict if such policies are carefully designed to fit the specific context and take into account the challenges that will arrive.
Improved observer-based robust adaptive control for a class of nonlinear systems with unknown deadzone
Authors: Jasim Ibrahim F
Published: November 2012

This article presents an improved observer-based robust adaptive control strategy for a class of nonlinear systems that have two features: (1) the coupling of unmeasured states and unknown parameters exist at the measured states dynamics and (2) unknown deadzone exists at the system actuation. At first, the bounds of the deadzone parameters are assumed to be known and a suitable control strategy is derived. This strategy involves the derivation of a control action, observer of the unmeasured states, and estimators of the unknown parameters such that global stable system performance is guaranteed. Then, another control strategy is proposed when the bounds of the deadzone parameters are unavailable. The second control algorithm comprises the derivation of suitable control action, observer of the unmeasured states, and estimators of the unknown parameters such that global stable system performance is assured and the anonymity of the bounds of the deadzone parameters is accommodated. Simulations are performed when using both control strategies for a nonlinear system that falls in the category of systems addressed in this article. The system is a single-link mechanical joint that suffers from friction torque, modeled by LuGre friction model, with unknown deadzone exists at its actuation. The simulation results show the high performance of the suggested control approaches.
Three-dimensional piezo-thermo-mechanical analysis for a finite cylindrical composite panel composed of cross-ply and piezoelectric laminate
Authors: Kang Yong Gang , Wang Zhong Qi
Published: November 2012

The exact three-dimensional piezo-thermo-mechanical solution for a finite cylindrical composite panel composed of cross-ply and piezoelectric laminate is presented in this article. The panel is simply supported at four end edges and is subjected to thermo-mechanical loadings on its top and bottom surfaces, respectively. The piezoelectric layers are polarized along radial direction as a sensor. The variables are expanded layerwise in Fourier series to satisfy the boundary conditions at the simply supported ends. As an example, a cross-ply laminated cylindrical panel made of alumina fiber reinforced aluminum composite, associated with a piezoelectric material of crystal class mm2 is calculated. Furthermore, some numerical results for the temperature change, the displacement, stresses, electric potential, and electric displacement distributions are shown in figures and briefly discussed.
Refractory hypoglycaemia in diabetes: a quinolone link
Authors: Swaminathan Krishnan , Vidi Keerthiga
Published: November 2012

Quinolones are commonly used medications due to their broad spectrum of action and high oral bioavailability. However, clinicians should be aware of potential toxicities including hypoglycaemia and cardiac rhythm disturbances. We present a case of quinolone induced severe refractory hypoglycaemia in a diabetic patient on sulphonylurea. Clinicians should educate patients about the possible hypoglycaemic effects of quinolones and assess the risk benefit ratio prior to initiating treatment with this group of drugs.
Finite element simulation of unsteady magneto-hydrodynamic transport phenomena on a stretching sheet in a rotating nanofluid
Authors: Rana Puneet , Bhargava Rama , Bég Osman A
Published: November 2012

This study examines theoretically and computationally the transient magneto-hydrodynamic boundary layer flow and heat transfer in an incompressible rotating nanofluid over a stretching continuous sheet, with a transverse magnetic field applied normal to the sheet plane. The three-dimensional conservation equations for mass, momentum, energy and species (nanoparticle) diffusion, are normalized into a system of two-dimensional dimensionless boundary layer equations, using appropriate scaling transformations. The resulting nanofluid transport model incorporates a Brownian motion parameter, thermophoresis parameter, rotation parameter, unsteady parameter, Prandtl number, Hartmann magnetic parameter and Lewis number, and physically realistic boundary conditions at the sheet surface and in the free stream. The nonlinear two-point boundary value problem is solved using a robust, efficient finite element method based on the variational formulation. A detailed evaluation of the effects of the governing physical parameters on the velocity components, temperature and nanoparticle concentration via graphical plots is conducted. Primary velocity is strongly retarded with increasing Hartmann number and there is also a reduction in secondary velocity magnitude. Both temperature and nanoparticle concentration are positively affected by the Hartmann number. Increasing rotational parameter decreases both primary and secondary velocity, and also depresses temperature and nanoparticle concentration. Unsteadiness parameter is generally found to enhance primary velocity and temperatures but exhibits a varied influence on secondary velocity and nanoparticle concentration. The reduced Nusselt number (wall temperature gradient) is observed to be depressed with both Brownian motion and thermophoresis effects, whereas the contrary behaviour is computed for the reduced Sherwood number (wall mass transfer gradient). The reduced Nusselt number and the Sherwood number also show a steady decrease with increasing rotational parameter. The present finite element method solutions have been validated extensively with the previously published results, demonstrating excellent correlation. The study has important applications in the manufacture and electromagnetic control of complex magnetic nanofluid materials of relevance to biomedical, energy systems and aerospace systems technologies.
Genome-derived insights into the biology of the hepatotoxic bloom-forming cyanobacterium Anabaena sp. strain 90
Authors: Wang Hao , Sivonen Kaarina , Rouhiainen Leo , Fewer David P , Lyra Christina , Rantala-Ylinen Anne , Vestola Johanna , Jokela Jouni , Rantasärkkä Kaisa , Li Zhijie , Liu Bin
Published: November 2012

Background

Cyanobacteria can form massive toxic blooms in fresh and brackish bodies of water and are frequently responsible for the poisoning of animals and pose a health risk for humans. Anabaena is a genus of filamentous diazotrophic cyanobacteria commonly implicated as a toxin producer in blooms in aquatic ecosystems throughout the world. The biology of bloom-forming cyanobacteria is poorly understood at the genome level.

Results

Here, we report the complete sequence and comprehensive annotation of the bloom-forming Anabaena sp. strain 90 genome. It comprises two circular chromosomes and three plasmids with a total size of 5.3 Mb, encoding a total of 4,738 genes. The genome is replete with mobile genetic elements. Detailed manual annotation demonstrated that almost 5% of the gene repertoire consists of pseudogenes. A further 5% of the genome is dedicated to the synthesis of small peptides that are the products of both ribosomal and nonribosomal biosynthetic pathways. Inactivation of the hassallidin (an antifungal cyclic peptide) biosynthetic gene cluster through a deletion event and a natural mutation of the buoyancy-permitting gvpG gas vesicle gene were documented. The genome contains a large number of genes encoding restriction-modification systems. Two novel excision elements were found in the nifH gene that is required for nitrogen fixation.

Conclusions

Genome analysis demonstrated that this strain invests heavily in the production of bioactive compounds and restriction-modification systems. This well-annotated genome provides a platform for future studies on the ecology and biology of these important bloom-forming cyanobacteria.
Transcriptome analysis of the spalax hypoxia survival response includes suppression of apoptosis and tight control of angiogenesis
Authors: Malik Assaf , Korol Abraham , Weber Mathias , Hankeln Thomas , Avivi Aaron , Band Mark
Published: November 2012

Background

The development of complex responses to hypoxia has played a key role in the evolution of mammals, as inadequate response to this condition is frequently associated with cardiovascular diseases, developmental disorders, and cancers. Though numerous studies have used mice and rats in order to explore mechanisms that contribute to hypoxia tolerance, these studies are limited due to the high sensitivity of most rodents to severe hypoxia. The blind subterranean mole ratSpalaxis a hypoxia tolerant rodent, which exhibits unique longevity and therefore has invaluable potential in hypoxia and cancer research.

Results

Using microarrays, transcript abundance was measured in brain and muscle tissues fromSpalaxand rat individuals exposed to acute and chronic hypoxia for varying durations. We found thatSpalaxglobal gene expression response to hypoxia differs from that of rat and is characterized by the activation of functional groups of genes that have not been strongly associated with the response to hypoxia in hypoxia sensitive mammals. Using functional enrichment analysis ofSpalaxhypoxia induced genes we found highly significant overrepresentation of groups of genes involved in anti apoptosis, cancer, embryonic/sexual development, epidermal growth factor receptor binding, coordinated suppression and activation of distinct groups of transcription factors and membrane receptors, in addition to angiogenic related processes. We also detected hypoxia induced increases of different criticalSpalaxhub gene transcripts, including antiangiogenic genes associated with cancer tolerance in Down syndrome human individuals.

Conclusions

This is the most comprehensive study ofSpalaxlarge scale gene expression response to hypoxia to date, and the first to use customSpalaxmicroarrays. Our work presents novel patterns that may underlie mechanisms with critical importance to the evolution of hypoxia tolerance, with special relevance to medical research.
Positive- and negative-acting regulatory elements contribute to the tissue-specific expression of INNER NO OUTER, a YABBY-type transcription factor gene in Arabidopsis
Authors: Simon Marissa K , Williams Luis A , Brady-Passerini Kristina , Brown Ryan H , Gasser Charles S
Published: November 2012

Background

The INNER NO OUTER (INO) gene, which encodes a YABBY-type transcription factor, specifies and promotes the growth of the outer integument of the ovule in Arabidopsis. INO expression is limited to the abaxial cell layer of the developing outer integument of the ovule and is regulated by multiple regions of the INO promoter, including POS9, a positive element that when present in quadruplicate can produce low-level expression in the normal INO pattern.

Results

Significant redundancy in activity between different regions of the INO promoter is demonstrated. For specific regulatory elements, multimerization or the addition of the cauliflower mosaic virus 35S general enhancer was able to activate expression of reporter gene constructs that were otherwise incapable of expression on their own. A new promoter element, POS6, is defined and is shown to include sufficient positive regulatory information to reproduce the endogenous pattern of expression in ovules, but other promoter regions are necessary to fully suppress expression outside of ovules. The full-length INO promoter, but not any of the INO promoter deletions tested, is able to act as an enhancer-blocking insulator to prevent the ectopic activation of expression by the 35S enhancer. Sequence conservation between the promoter regions of Arabidopsis thaliana, Brassica oleracea and Brassica rapa aligns closely with the functional definition of the POS6 and POS9 regions, and with a defined INO minimal promoter. The B. oleracea INO promoter is sufficient to promote a similar pattern and level of reporter gene expression in Arabidopsis to that observed for the Arabidopsis promoter.

Conclusions

At least two independent regions of the INO promoter contain sufficient regulatory information to direct the specific pattern but not the level of INO gene expression. These regulatory regions act in a partially redundant manner to promote the expression in a specific pattern in the ovule and suppress expression outside of ovules. Establishment of this pattern requires cooperation and competition between multiple positive and negative regulatory elements.
Clinical procedure for colon carcinoma tissue sampling directly affects the cancer marker-capacity of VEGF family members
Authors: Pringels Sarah , Van Damme Nancy , De Craene Bram , Pattyn Piet , Ceelen Wim , Peeters Marc , Grooten Johan
Published: November 2012

Background

mRNA levels of members of the Vascular Endothelial Growth Factor family (VEGF-A, -B, -C, -D, Placental Growth Factor/PlGF) have been investigated as tissue-based markers of colon cancer. These studies, which used specimens obtained by surgical resection or colonoscopic biopsy, yielded contradictory results. We studied the effect of the sampling method on the marker accuracy of VEGF family members.

Methods

Comparative RT-qPCR analysis was performed on healthy colon and colon carcinoma samples obtained by biopsy (n = 38) or resection (n = 39) to measure mRNA expression levels of individual VEGF family members. mRNA levels of genes encoding the eicosanoid enzymes cyclooxygenase 2 (COX2) and 5-lipoxygenase (5-LOX) and of genes encoding the hypoxia markers glucose transporter 1 (GLUT-1) and carbonic anhydrase IX (CAIX) were included as markers for cellular stress and hypoxia.

Results

Expression levels of COX2, 5-LOX, GLUT-1 and CAIX revealed the occurrence in healthy colon resection samples of hypoxic cellular stress and a concurrent increment of basal expression levels of VEGF family members. This increment abolished differential expression of VEGF-B and VEGF-C in matched carcinoma resection samples and created a surgery-induced underexpression of VEGF-D. VEGF-A and PlGF showed strong overexpression in carcinoma samples regardless of the sampling method.

Conclusions

Sampling-induced hypoxia in resection samples but not in biopsy samples affects the marker-reliability of VEGF family members. Therefore, biopsy samples provide a more accurate report on VEGF family mRNA levels. Furthermore, this limited expression analysis proposes VEGF-A and PlGF as reliable, sampling procedure insensitive mRNA-markers for molecular diagnosis of colon cancer.
The growth and composition of primary and community-based care services. Metrics and evidence from the Italian National Health Service
Authors: Longo Francesco , Salvatore Domenico , Tasselli Stefano
Published: November 2012

Background

Over the past few decades, in OECD countries there has been a general growing trend in the prevalence of out-of-hospital healthcare services, but there is a general lack of data on the use of these services.

Methods

We defined a list of 303 indicators related to primary and community healthcare services in collaboration with 13 Italian Local Health Authorities (LHAs). Then, for each LHA, we collected and analyzed these indicators for two different years (2003 and 2007).

Results

Out-of-hospital care absorbs 56% of all costs in our sample of LHAs. Expenditure on outpatients’ visits to specialists and on diagnostic examinations accounts for 13% of the costs, while spending on primary care (including prevention and public health) accounts for 9%, and for intermediate structures (including those related to rehabilitation, elderly people, disabled people, and mental health) the figure is 11%. Different Italian LHAs have made different strategic choices with respect to primary and community-based care (PCC).

Conclusions

Two distinct strategic orientations in the adoption of PCC services by LHAs has emerged from our study. The first has been an investment mainly in ambulatory and home-based primary care services in order to increase the number of low-complexity settings. A second strategy has prioritized the allocation of resources to intermediate inpatient structures for specific types of patients, namely elderly and disabled people, post-acute patients in need of rehabilitation and long-term care, and patients in hospices.
Unique functions of CHK1 and WEE1 underlie synergistic anti-tumor activity upon pharmacologic inhibition
Authors: Guertin Amy D , Martin Melissa M , Roberts Brian , Hurd Melissa , Qu Xianlu , Miselis Nathan R , Liu Yaping , Li Jing , Feldman Igor , Benita Yair , Bloecher Andrew , Toniatti Carlo , Shumway Stuart D
Published: November 2012

Background

Inhibition of kinases involved in the DNA damage response sensitizes cells to genotoxic agents by abrogating checkpoint-induced cell cycle arrest. CHK1 and WEE1 act in a pathway upstream of CDK1 to inhibit cell cycle progression in response to damaged DNA. Therapeutic targeting of either CHK1 or WEE1, in combination with chemotherapy, is under clinical evaluation. These studies examine the overlap and potential for synergy when CHK1 and WEE1 are inhibited in cancer cell models.

Methods

Small molecules MK-8776 and MK-1775 were used to selectively and potently inhibit CHK1 and WEE1, respectively.

Results

In vitro, the combination of MK-8776 and MK-1775 induces up to 50-fold more DNA damage than either MK-8776 or MK-1775 alone at a fixed concentration. This requires aberrant cyclin-dependent kinase activity but does not appear to be dependent on p53 status alone. Furthermore, DNA damage takes place primarily in S-phase cells, implying disrupted DNA replication. When dosed together, the combination of MK-8776 and MK-1775 induced more intense and more durable DNA damage as well as anti-tumor efficacy than either MK-8776 or MK-1775 dosed alone. DNA damage induced by the combination was detected in up to 40% of cells in a treated xenograft tumor model.

Conclusions

These results highlight the roles of WEE1 and CHK1 in maintaining genomic integrity. Importantly, the strong synergy observed upon inhibition of both kinases suggests unique yet complimentary anti-tumor effects of WEE1 and CHK1 inhibition. This demonstration of DNA double strand breaks in the absence of a DNA damaging chemotherapeutic provides preclinical rationale for combining WEE1 and CHK1 inhibitors as a cancer treatment regimen.
3D modeling of dual-gate FinFET
Authors: Mil’shtein Samson , Devarakonda Lalitha , Zanchi Brian , Palma John
Published: November 2012

The tendency to have better control of the flow of electrons in a channel of field-effect transistors (FETs) did lead to the design of two gates in junction field-effect transistors, field plates in a variety of metal semiconductor field-effect transistors and high electron mobility transistors, and finally a gate wrapping around three sides of a narrow fin-shaped channel in a FinFET. With the enhanced control, performance trends of all FETs are still challenged by carrier mobility dependence on the strengths of the electrical field along the channel. However, in cases when the ratio of FinFET volume to its surface dramatically decreases, one should carefully consider the surface boundary conditions of the device. Moreover, the inherent non-planar nature of a FinFET demands 3D modeling for accurate analysis of the device performance. Using the Silvaco modeling tool with quantization effects, we modeled a physical FinFET described in the work of Hisamoto et al. (IEEE Tran. Elec. Devices 47:12, 2000) in 3D. We compared it with a 2D model of the same device. We demonstrated that 3D modeling produces more accurate results. As 3D modeling results came close to experimental measurements, we made the next step of the study by designing a dual-gate FinFET biased at V
g1 > V
g2. It is shown that the dual-gate FinFET carries higher transconductance than the single-gate device.