bluuebunny/crossref_metadata_2025 huggingface dataset:
Dependence of Hot Carrier Reliability and Low Frequency Noise on Channel Stress in Nanoscale n-Channel Metal–Oxide–Semiconductor Field-Effect Transistors
Authors: Kwon Hyuk-Min , Bok Jung-Deuk , Han In-Shik , Park Sang-Uk , Jung Yi-Jung , Jang Jae-Hyung , Ko Sung-Yong , Lee Won-Mook , Lee Ga-Won , Lee Hi-Deok
Published: October 2011

In this paper, the dependence of low-frequency (LF) noise, such as 1/f noise and random telegraph signal (RTS) noise, and the hot carrier reliability in n-channel metal–oxide–semiconductor field-effect transistors (NMOSFETs) on channel stress has been studied. The normalized noise power spectral density (S

I
D
/I
D
2) and RTS amplitude of NMOSFETs with compressive channel stress are greater than those with tensile channel stress because the active traps contributing to RTS noise with compressive stress are distributed closer to the Si/SiO2 interface. LF noise characteristics, as well as device performance are enhanced by introducing tensile channel stress to nanoscale NMOSFETs. However, it is shown that device degradation caused by tensile channel stress is greater than that caused by compressive channel stress under channel hot carrier (CHC) and drain avalanche hot carrier (DAHC) stress conditions. Therefore, concurrent consideration of reliability and LF noise characteristics as well as dc device performance is necessary in channel strain engineering for next generation complementary metal–oxide–semiconductor field-effect transistors (CMOSFETs) especially for analog or mixed signal integrated circuit applications.
Improvement in Characteristics of Low-Temperature Polycrystalline Silicon Thin Film Transistors with High-Efficiency and Low-Damage N2 Plasma Pretreatment
Authors: Fan Ching-Lin , Lin Yi-Yan , Wang Shou-Kuan
Published: October 2011

In this study, the pretreatment on the surface of a polycrystalline silicon (poly-Si) channel layer using the N2 plasma generated by a hollow cathode (HC) generation system was proposed. It was found that the pretreatment can not only passivate the defect states but also present a smooth oxide/poly-Si interface, which can significantly improve the device performance. Therefore, the scheme used can offer a high-efficiency passivation with low plasma damage. In addition, the reliability of the device was greatly enhanced after the N2 plasma pretreatment as a result of the formation of strong Si–N bonds and a smooth oxide/poly-Si interface. We believe that the N2 plasma pretreatment using the HC system is suitable for the mass-production of high-resolution displays.
Kinetic Effects of O-Vacancy Generated by GeO2/Ge Interfacial Reaction
Authors: Wang Sheng Kai , Kita Koji , Nishimura Tomonori , Nagashio Kosuke , Toriumi Akira
Published: October 2011

Ge is a promising candidate for replacing Si for future complementary metal–oxide–semiconductors (CMOSs) because of its high mobility. However, the intrinsic GeO2/Ge instability is a major obstacle to achieving a good interface. The reaction at the GeO2/Ge interface and the kinetic effects initiated by the interfacial reaction are systematically studied in this paper. The interfacial reaction is regarded as a redox reaction mediated by the oxygen vacancy (Vo). Owing to the incorporation of Vo into GeO2, several kinetic effects are brought about. In this paper, we discuss these Vo-induced kinetic effects such as GeO desorption, GeO2 crystallization with an α-quartz-like phase, and local void formation on GeO2. A unified model is proposed by taking Vo generation at the GeO2/Ge interface into consideration.
Detection of Multivalency Charge States in Complex and Elemental Transition Metal Oxides by X-ray Absorption Spectroscopy: Controlled Multivalency as a Pathway to Device Functionality
Authors: Lucovsky Gerald , Miotti Leonardo , Bastos Karen Paz
Published: October 2011

Multivalent charge states, or simply multivalency, introduced in transition metal elemental and complex oxides by substitutional alloy formation, provide a pathway for introducing new device functionalities. This article discusses alloy induced multivalency in three transition metal oxides resulting in different functionalities. These are: (i) an insulator to metal transition in GdScO3 by substitution of tetravalent Ti for trivalent Sc in the ScO2 planes of cubic perovskite structured GdSc1-x
Ti
x
O3 alloys, above a percolation threshold of x = 0.165: (ii) double exchange magnetism in LaMnO3 by substitution of divalent Sr for trivalent La for the alloy composition La0.80Sr0.20MnO3; and (iii) controlled introduction of O-vacancy negative ion states as a pathway to current-controlled memory devices in tetravalent TiO2–trivalent Ti2O3 Magnéli phase alloys with a general formula Ti
n
O2n-1. In two of these alloys, the GdSc1-x
T
x
O3 and Ti
n
O2n-1 alloys, additional valence states, as Ti2+ and Sc2+ in the Gd scandates, and Ti2+ in the Magnéli phases, are introduced by strain-reduction compensation associated with the ∼9% difference between the ionic radii Ti4+ and Ti3+. Spectroscopic detection is based on charge transfer multiplet theory as applied to Ti, Sc, and Mn L2,3 X-ray absorption spectra., in which the number of features in the L2 and L3 spectral regimes is significantly increased when either Ti or Mn is present in more than one valence state.
Effects of Thickness Effect and Rapid Thermal Annealing on pH Sensing Characteristics of Thin HfO2 Films Formed by Atomic Layer Deposition
Authors: Lu Tseng-Fu , Chuang Hao-Chun , Wang Jer-Chyi , Yang Chia-Ming , Kuo Pei-Chun , Lai Chao-Sung
Published: October 2011

In this article, thin hafnium oxide (HfO2) films deposited by atomic layer deposition (ALD) were investigated as a sensing layer on an electrolyte–insulator–semiconductor (EIS) structure for pH sensor applications. Compared with sputtering, ALD provides the possibility of shrinking the thickness of the HfO2 sensing layer down to 3.5 nm with a low drift coefficient (<0.2 mV/h). To increase the pH response, an additional rapid thermal annealing was performed on a 3.5-nm-thick ALD-HfO2 film. After annealing at 900 °C, the pH sensitivity could be effectively increased to that near the Nernstian response (59.6 mV/pH), and the drift coefficient (<1 mV/h) and hysteresis width (4.26 mV) are still sufficient. On the basis of the results of atomic force microscopy (AFM) analysis, the increase in surface roughness is possibly the reason for the increase in pH response after annealing. For compatibility with advanced complementary metal–oxide–semiconductor (CMOS) technology, the thin ALD-HfO2 film is a promising candidate for pH sensor fabrications.
Evaluation of Chemical Structure and Resistance Switching Characteristics of Undoped Titanium Oxide and Titanium–Yttrium Mixed Oxide
Authors: Ohta Akio , Goto Yuta , Wei Guobin , Murakami Hideki , Higashi Seiichiro , Miyazaki Seiichi
Published: October 2011

We have studied the chemical bonding features in the region near the TiO2/Pt interface after resistance change to gain a better understanding of the mechanism of resistance switching in TiO2-based resistance random access memory (ReRAM). For the Pt/TiO2/Pt structure after resistance switching, oxidation of the Pt electrode at the Pt/TiO2 interface in switching from a high resistance state (HRS) to a low resistance state (LRS) and reduction of this Pt-oxide in switching from the LRS to the HRS were observed by hard X-ray photoelectron spectroscopy. The result suggests that the generation of oxygen vacancies in the Ti-oxide matrix is responsible for the formation of the conductive pass resulting in the LRS and that repeatable redox reaction at the Pt/TiO2 interface plays an important role in resistance switching behavior. To modify the oxide network, which leads to the change in the conduction pass formation, trivalent Y ions were added to the oxide matrix of quadrivalent Ti ions. Raman scattering and X-ray diffraction measurements show that the crystallization of TiO2 by thermal annealing was suppressed by the Y2O3 addition. In Au/TiY
x
O
y
/Pt structures, it has been demonstrated that the variations in resistance switching voltages are markedly suppressed by the Y2O3 addition to TiO2.
Bird Flight-Inspired Routing Protocol for Mobile Ad Hoc Networks
Authors: Misra Sudip , Rajesh Gopidi
Published: October 2011

One of the major challenges in the research of mobile ad hoc networks is designing dynamic, scalable, and low cost (in terms of utilization of resources) routing protocols usable in real-world applications. Routing in ad hoc networks has been explored to a large extent over the past decade and different protocols have been proposed. They are based on a two-dimensional view of the ad hoc network geographical region, and are not always realistic. In this article, we propose a bird flight-inspired, highly scalable, dynamic, energy-efficient, and position-based routing protocol called Bird Flight-Inspired Routing Protocol (BFIRP). The proposed protocol is inspired by the navigation of birds over long distances following the great circle arc, the shortest arc connecting two points on the surface of a sphere. This sheds light on how birds save their energy while navigating over thousands of miles. The proposed algorithm can be readily applied in many real-world applications, as it is designed with a realistic three-dimensional view of the network’s geographic region. In the proposed algorithm, each node obtains its location coordinates (X, Y, Z), and speed from the GPS (Global Positioning System); whereas, the destination’s location coordinates (X, Y, Z), and speed are obtained from any other distributed localized service. Based on the location information, the source and each intermediate node choose their immediate neighbor as the next hop that has the maximum priority. The priority is calculated by taking into consideration the energy of the node, the distance between the node and the destination and the degree of closeness of the node to the trajectory of the great circle arc between the current node and the destination. The proposed algorithm is simulated in J-SIM and compared with the algorithms of Ad Hoc On Demand Distance Vector (AODV), and Most Forward Within Distance R (MFR) routing protocols. The results of the simulations show that the proposed BFIRP algorithm is highly scalable, and has low end-to-end delay compared to AODV. The algorithm is also simulated in various scenarios, and the results demonstrate that BFIRP is more efficient than AODV in energy and throughput by 20% and 15% respectively. It also shows satisfactory improvement over MFR in terms of throughput and routing overhead.
Scalable Stealth Mode P2P Overlays of Very Small Constant Degree
Authors: Jelasity Márk , Bilicki Vilmos
Published: October 2011

P2P technology has recently been adopted by Internet-based malware as a fault tolerant and scalable communication medium. Due to its decentralized and self-organizing nature, P2P malware is harder to detect and block, especially if it utilizes specialized techniques for hiding. We analyze a number of hiding strategies through extensive and realistic simulations over a model of the AS-level Internet topology. We show that the most effective strategy to avoid detection is to drastically reduce the maximal number of peers a node communicates with. While overlay networks of a small constant maximal degree are generally considered to be unscalable, we argue that it is possible to design them to be scalable, efficient, and robust. An important implication is that stealth mode P2P malware that is very difficult to discover with state-of-the-art methods is a plausible threat. We discuss algorithms and theoretical results that support the scalability of stealth mode overlays, and we present realistic event-based simulations of a proof-of-concept system. Besides the context of P2P malware, some of our results are of general interest in the area of constant degree overlays in connection with the problem of how to maintain reasonable performance and reliability with the smallest degree possible.
Mechanisms for the control of matriptase activity in the absence of sufficient HAI-1
Authors: Xu Han , Xu Zhenghong , Tseng I-Chu , Chou Feng-Pai , Chen Ya-Wen , Wang Jehng-Kang , Johnson Michael D. , Kataoka Hiroaki , Lin Chen-Yong
Published: October 2011

Matriptase proteolytic activity must be tightly controlled for normal placental development, epidermal function, and epithelial integrity. Although hepatocyte growth factor activator inhibitor-1 (HAI-1) represents the predominant endogenous inhibitor for matriptase and the protein molar ratio of HAI-1 to matriptase is determined to be >10 in epithelial cells and the majority of carcinoma cells, an inverse HAI-1-to-matriptase ratio is seen in some ovarian and hematopoietic cancer cells. In the current study, cells with insufficient HAI-1 are investigated for the mechanisms through which the activity of matriptase is regulated. When matriptase activation is robustly induced in these cells, activated matriptase rapidly forms two complexes of 100- and 140-kDa in addition to the canonical 120-kDa matriptase-HAI-1 complex already described. Both 100- and 140-kDa complexes contain two-chain, cleaved matriptase but are devoid of gelatinolytic activity. Further biochemical characterization shows that the 140-kDa complex is a matriptase homodimer and that the 100-kDa complexes appear to contain reversible, tight binding serine protease inhibitor(s). The formation of the 140-kDa matriptase dimer is strongly associated with matriptase activation, and its levels are inversely correlated with the ratio of HAI-1 to matriptase. Given these observations and the likelihood that autoactivation requires the interaction of two matriptase molecules, it seems plausible that this activated matriptase homodimer may represent a matriptase autoactivation intermediate and that its accumulation may serve as a mechanism to control matriptase activity when protease inhibitor levels are limiting. These data suggest that matriptase activity can be rapidly inhibited by HAI-1 and other HAI-1-like protease inhibitors and “locked” in an inactive autoactivation intermediate, all of which places matriptase under very tight control.
Hormonal modulation of the heat shock response: insights from fish with divergent cortisol stress responses
Authors: LeBlanc Sacha , Höglund Erik , Gilmour Kathleen M. , Currie Suzanne
Published: October 2011

Acute temperature stress in animals results in increases in heat shock proteins (HSPs) and stress hormones. There is evidence that stress hormones influence the magnitude of the heat shock response; however, their role is equivocal. To determine whether and how stress hormones may affect the heat shock response, we capitalized on two lines of rainbow trout specifically bred for their high (HR) and low (LR) cortisol response to stress. We predicted that LR fish, with a low cortisol but high catecholamine response to stress, would induce higher levels of HSPs after acute heat stress than HR trout. We found that HR fish have significantly higher increases in both catecholamines and cortisol compared with LR fish, and LR fish had no appreciable stress hormone response to heat shock. This unexpected finding prevented further interpretation of the hormonal modulation of the heat shock response but provided insight into stress-coping styles and environmental stress. HR fish also had a significantly greater and faster heat shock response and less oxidative protein damage than LR fish. Despite these clear differences in the physiological and cellular responses to heat shock, there were no differences in the thermal tolerance of HR and LR fish. Our results support the hypothesis that responsiveness to environmental change underpins the physiological differences in stress-coping styles. Here, we demonstrate that the heat shock response is a distinguishing feature of the HR and LR lines and suggest that it may have been coselected with the hormonal responses to stress.
Surface charge impact in low-magnesium model of seizure in rat hippocampus
Authors: Isaev Dmytro , Ivanchick Gleb , Khmyz Volodymyr , Isaeva Elena , Savrasova Alina , Krishtal Oleg , Holmes Gregory L. , Maximyuk Oleksandr
Published: October 2011

Putative mechanisms of induction and maintenance of seizure-like activity (SLA) in the low Mg2+model of seizures are: facilitation of NMDA receptors and decreased surface charge screening near voltage-gated channels. We have estimated the role of such screening in the early stages of SLA development at both physiological and room temperatures. External Ca2+and Mg2+promote a depolarization shift of the sodium channel voltage sensitivity; when examined in hippocampal pyramidal neurons, the effect of Ca2+was 1.4 times stronger than of Mg2+. Removing Mg2+from the extracellular solution containing 2 mM Ca2+induced recurrent SLA in hippocampal CA1 pyramidal layer in 67% of slices. Reduction of [Ca2+]oto 1 mM resulted in 100% appearance of recurrent SLA or continuous SLA. Both delay before seizure activity and the inter-SLA time were significantly reduced. Characteristics of seizures evoked in low Mg2+/1 mM Ca2+/3.5 K+were similar to those obtained in low Mg2+/2 Ca2+/5mM K+, suggesting that reduction of [Ca2+]oto 1 mM is identical to the increase in [K+]oto 5 mM in terms of changes in cellular excitability and seizure threshold. An increase of [Ca2+]oto 3 mM completely abolished SLA generation even in the presence of 5 mM [K+]o. A large variation in the ability of [Ca2+]oto stop epileptic discharges in initial stage of SLA was found. Our results indicate that surface charge of the neuronal membrane plays a crucial role in the initiation of low Mg2+-induced seizures. Furthermore, our study suggests that Ca2+and Mg2+, through screening of surface charge, have important anti-seizure and antiepileptic properties.
Odontogenic Keratocyst Looks Can Be Deceptive, Causing Endodontic Misdiagnosis
Authors: Veena K. M. , Rao Rekha , Jagadishchandra H. , Rao Prasanna Kumar
Published: October 2011

Odontogenic keratocyst (OKC) is the cyst arising from the cell rests of dental lamina. It can occur anywhere in the jaw, but commonly seen in the posterior part of the mandible. Radiographically, most OKCs are unilocular when presented at the periapex and can be mistaken for radicular or lateral periodontal cyst. When the cyst is multilocular and located at the molar ramus area, it may be confused to ameloblastoma. Lots of cases have been reported in the literature where OKC is associated with the nonvital tooth. So trauma could be one of the reasons in inducing this cyst. In our case, it was in the anterior region at the periapex of nonvital tooth having traumatic occlusion. Hence, the diagnosis of radicular cyst was made and endodontic treatment was done.
Survival of Exfoliated Epithelial Cells: A Delicate Balance between Anoikis and Apoptosis
Authors: Kaeffer Bertrand
Published: October 2011

The recovery of exfoliated cells from biological fluids is a noninvasive technology which is in high demand in the field of translational research. Exfoliated epithelial cells can be isolated from several body fluids (i.e., breast milk, urines, and digestives fluids) as a cellular mixture (senescent, apoptotic, proliferative, or quiescent cells). The most intriguing are quiescent cells which can be used to derive primary cultures indicating that some phenotypes retain clonogenic potentials. Such exfoliated cells are believed to enter rapidly in anoikis after exfoliation. Anoikis can be considered as an autophagic state promoting epithelial cell survival after a timely loss of contact with extracellular matrix and cell neighbors. This paper presents current understanding of exfoliation along with the influence of methodology on the type of gastrointestinal epithelial cells isolated and, finally, speculates on the balance between anoikis and apoptosis to explain the survival of gastrointestinal epithelial cells in the environment.
Improving Islet Engraftment by Gene Therapy
Authors: Wang Xiaojie , Meloche Mark , Verchere C. Bruce , Ou Dawei , Mui Alice , Warnock Garth L.
Published: October 2011

Islet cell transplantation is currently the only feasible long-term treatment option for patients with type 1 diabetes. However, the majority of transplanted islets experience damage and apoptosis during the isolation process, a blood-mediated inflammatory microenvironment in the portal vein upon islet infusion, hypoxia induced by the low oxygenated milieu, and poor-revascularization-mediated lack of nutrients, and impaired hormone modulation in the local transplanted site. Strategies using genetic modification methods through overexpression or silencing of those proteins involved in promoting new formation of blood vessels or inhibition of apoptosis may overcome these hurdles and improve islet engraftment outcomes.
An Efficient Therapy Strategy under a Novel HIV Model
Authors: Zhang Chunming , Yang Xiaofan , Liu Wanping , Yang Lu-Xing
Published: October 2011

By incorporating the chemotherapy into a previous model describing the interaction of the immune system with the human immunodeficiency virus (HIV), this paper proposes a novel HIV virus spread model with control variables. Our goal is to maximize the number of healthy cells and, meanwhile, to minimize the cost of chemotherapy. In this context, the existence of an optimal control is proved. Experimental results show that, under this model, the spread of HIV virus can be controlled effectively.
Wear Behavior and Its Correlation with Mechanical Properties of TiB2Reinforced Aluminium-Based Composites
Authors: Dhokey N. B. , Rane K. K.
Published: October 2011

Aluminium-based TiB2reinforced composite is a promising material to be used as brake drum material, and it may emerge as substitute for conventional gray cast iron. Aluminium-based composites containing 2% by wt copper reinforced with 2.5 and 5 wt% TiB2composites were made in induction furnace by in situ synthesis process using simultaneous addition of halide fluxes (K2TiF6and KBF4). These cast composites were evaluated for microstructures, hardness, flow curve properties, and tensile properties. It was observed that overall wear behavior gave reasonably good correlation with mechanical properties of composites as compared to gray cast iron.
Homosexual Pairing within a Swarm-Based Mating System: The Case of the Chironomid Midge
Authors: McLachlan Athol J.
Published: October 2011

Homosexuality has been dubbed the Darwinian paradox, because it raises the question of how behaviour that would seem to reduce the chance of successful mating can be maintained by natural selection. This question rests on the assumption that same sex mating is the result of active choice of partner, hardwired into the mating behaviour, but there is an alternative explanation for such behaviour. I refer to the possibility that same-sex mating is the result, not of adaptive behaviour at all, but rather of errors due to imprecise sensory machinery. Such an explanation finds support within the mating system of insects with swarm-based mating systems. To explore this case, I turn to the common chironomid midge. I show that homosexual pairing here, exclusively involving male/male pairs, is common. I attempt to show that this observation, together with data on insect predators of swarming midges, can be used to penetrate the mysteries of this fascinating but elusive mating system.
Clinicopathological Comparison of Adenocarcinoma of Cervix and Endometrium Using Cell Cycle Markers: P16ink4a, P21waf1, and p27Kip1 on 132 Cancers
Authors: Marican Abu Backer Farveen , Nik Mustapha Nik Raihan , Othman Nor Hayati
Published: October 2011

Objective. We studied the clinicopathological parameters of adenocarcinoma arising from endocervix (ECA) and from endometrium (EMA) based on the expression of P16ink4a, P21waf1, and p27Kip1 proteins.Study Design. Immunohistochemistry was done on sections of confirmed ECA and EMA from hysterectomy specimens which have had no prior chemotherapy/radiotherapy.Results. There were 40 ECAs and 92 EMAs. The mean age of ECA was 49.82 (SD 10.29); the youngest was 30 years old and the oldest 75 years old. The mean age of EMA was 54.45 (SD 10.92); the youngest was 30 years old and the oldest was 82 years old. For ECA, the size of the tumour is significantly associated with age and with depth of infiltration. FIGO stage is associated with histological grade. p21WAF1 expression is significantly associated with infiltration of the corpus and lymph node metastasis. p27Kip1 expression is significantly associated with lymph node invasion. The presence of lymph node metastasis is strongly associated when p16INK4a and p27Kip1 expressions are analyzed in combination. For EMA, p16INK4a expression is associated with histologic grade.Conclusion. Our study shows that we could use these cell cycle markers as predictors for more aggressive subsets of adenocarcinoma of the cervix and endometrium.
Morphologic Heterogeneity in Carcinosarcoma of the Gallbladder: Report of a Rare Cases
Authors: Krishnamurthy Vani , Shivalingiah Sheela Devi C. , Ravishankar Sunila , Manjunath Gubbanna V.
Published: October 2011

Carcinosarcoma is a rare tumor composed of variable proportions of carcinomatous and sarcomatous elements and comprises less than one percent of all gallbladder malignancies. In most reported cases of carcinosarcoma of gallbladder, the epithelial component is adenocarcinoma. The mesenchymal component varies from homogenous sarcoma to more heterotopic elements like malignant bone, cartilage, and other mesenchymal tissues. We report a rare case of carcinosarcoma of the gallbladder in an 83-year-old male, with the carcinomatous component represented by undifferentiated carcinoma (spindle and giant cell type with osteoclastic giant cells) and the mesenchymal component seen as foci of chondrosarcoma.
Market Dynamics When Agents Anticipate Correlation Breakdown
Authors: Falbo Paolo , Grassi Rosanna
Published: October 2011

The aim of this paper is to analyse the effect introduced in the dynamics of a financial market
when agents anticipate the occurrence of a correlation breakdown. What emerges is that correlation
breakdowns can act both as a consequence and as a triggering factor in the emergence of financial
crises rational bubbles. We propose a market with two kinds of agents: speculators and rational
investors. Rational agents use excess demand information to estimate the variance‐covariance
structure of assets returns, and their investment decisions are represented as a Markowitz optimal
portfolio allocation. Speculators are uninformed agents and form their expectations by imitative
behavior, depending on market excess demand. Several market equilibria result, depending on the
prevalence of one of the two types of agents. Differing from previous results in the literature on
the interaction between market dynamics and speculative behavior, rational agents can generate
financial crises, even without the speculator contribution.
Thermal Behavior with Mechanical Property of Fluorinated Silane Functionalized Superhydrophobic Pullulan/Poly(vinyl alcohol) Blends by Electrospinning Method
Authors: Karim Mohammad Rezaul , Islam Md. Shahidul
Published: October 2011

Fluorinated silane functionalized superhydrophobic pullulan/poly(vinyl alcohol) (PULL/PVA) blend membrane with water contact angle larger than 150° has been prepared by the electrospinning method. The morphology, thermal stability, and mechanical property of the membranes are characterized using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and ZWICK materials testing machine, respectively. Interactions between PULL and PVA and PULL/PVA blends with perfluorooctyltriethoxysilane (PFOTES) of the membranes are analyzed using differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR). Contact angles and water drops on the surface of the membrane are measured by video microscopy. The study shows that the addition of minor quantity of PVA with PULL results in improvement in thermal stability and mechanical property (tensile strength) of the PULL membranes.
Making Organic‐Inorganic Nanocomposites via Selective Dispersion of PS‐Tethered SiO2 Particles in Polystyrene‐Block‐Polymethylmethacrylate Copolymer
Authors: Liu Chia-Hong , Chiu Li-Ko , Yeh Je-Yuan , Tsiang Raymond Chien-Chao
Published: October 2011

SiO2 nanoparticles have been dispersed selectively in the polystyrene (PS) microdomain of polystyrene‐block‐polymethylmethacrylate (PS‐b‐PMMA) block copolymer via the blending of PS‐b‐PMMA with PS‐tethered SiO2. As observed by atomic force microscopy and scanning electron microscopy, the incorporation of SiO2 particles not only enlarges the PS microdomain but also reduces the surface energy of the PS microdomain and transforms the morphology from either lamellar layers or cylinders to islanded bicontinuous microstructures. Blending SiO2 particles with an excessive amount or with a particle size larger than that of the PS microdomain would pose an extreme constraint on the molecular rearrangement, unstabliize the microdomain separation, and even make the microdomain separation unobservable. The nanosize and the uniform distribution of the PS microdomain in the PS‐b‐PMMA polymer have thus enabled us to achieve a uniform distribution of the inorganic SiO2 particles in the organic polymeric matrix.
CD154: An Immunoinflammatory Mediator in Systemic Lupus Erythematosus and Rheumatoid Arthritis
Authors: Alaaeddine Nada , Hassan Ghada S. , Yacoub Daniel , Mourad Walid
Published: October 2011

Systemic lupus erythematosus and rheumatoid arthritis are two major chronic inflammatory autoimmune diseases with significant prevalence rates among the population. Although the etiology of these diseases remains unresolved, several evidences support the key role of CD154/CD40 interactions in initiating and/or propagating these diseases. The discovery of new receptors (αIIbβ3,α5β1, andαMβ2) for CD154 has expanded our understanding about the precise role of this critical immune mediator in the physiopathology of chronic inflammatory autoimmune diseases in general, and in systemic lupus erythematosus and rheumatoid arthritis in particular. This paper presents an overview of the interaction of CD154 with its various receptors and outlines its role in the pathogenesis of systemic lupus erythematosus and rheumatoid arthritis. Moreover, the potential usefulness of various CD154-interfering agents in the treatment and prevention of these diseases is also discussed.
Hopfield Neural Network Optimized Fuzzy Logic Controller for Maximum Power Point Tracking in a Photovoltaic System
Authors: Subiyanto  , Mohamed Azah , Shareef Hussain
Published: October 2011

This paper presents a Hopfield neural network (HNN) optimized fuzzy logic controller (FLC) for maximum power point tracking in photovoltaic (PV) systems. In the proposed method, HNN is utilized to automatically tune the FLC membership functions instead of adopting the trial-and-error approach. As in any fuzzy system, initial tuning parameters are extracted from expert knowledge using an improved model of a PV module under varying solar radiation, temperature, and load conditions. The linguistic variables for FLC are derived from, traditional perturbation and observation method. Simulation results showed that the proposed optimized FLC provides fast and accurate tracking of the PV maximum power point under varying operating conditions compared to that of the manually tuned FLC using trial and error.
Medical Pattern Recognition: Applying an Improved Intuitionistic Fuzzy Cross-Entropy Approach
Authors: Hung Kuo-Chen
Published: October 2011

One of the toughest challenges in medical diagnosis is the handling of uncertainty. Since medical diagnosis with respect to the symptoms uncertain, they will be assumed to have an intuitive nature. Thus, to obtain the uncertain optimism degree of the doctor, fuzzy linguistic quantifiers will be used. The aim of this article is to provide an improved nonprobabilistic entropy approach to support doctors examining the work of the preliminary diagnosing. The proposed entropy measure is based on intuitionistic fuzzy sets, extrainformation regarding hesitation degree, and an intuitive and mathematical connection between the notions of entropy in terms of fuzziness and intuitionism has been revealed. An illustrative example for medical pattern recognition demonstrates the usefulness of this study. Furthermore, in order to make computing and ranking results easier and to increase the recruiting productivity, a computer-based interface system has been developed to support doctors in making more efficient judgments.
High Complement Factor I Activity in the Plasma of Children with Autism Spectrum Disorders
Authors: Momeni Naghi , Brudin Lars , Behnia Fatemeh , Nordström Berit , Yosefi-Oudarji Ali , Sivberg Bengt , Joghataei Mohammad T. , Persson Bengt L.
Published: October 2011

Autism spectrum disorders (ASDs) are neurodevelopmental and behavioural syndromes affecting social orientation, behaviour, and communication that can be classified as developmental disorders. ASD is also associated with immune system abnormality. Immune system abnormalities may be caused partly by complement system factor I deficiency. Complement factor I is a serine protease present in human plasma that is involved in the degradation of complement protein C3b, which is a major opsonin of the complement system. Deficiency in factor I activity is associated with an increased incidence of infections in humans. In this paper, we show that the mean level of factor I activity in the ASD group is significantly higher than in the control group of typically developed and healthy children, suggesting that high activity of complement factor I might have an impact on the development of ASD.
Application of Bioluminescence Imaging forIn VivoMonitoring of Fungal Infections
Authors: Brock Matthias
Published: October 2011

Fungi can cause severe invasive infections especially in the immunocompromised host. Patient populations at risk are increasing due to ongoing developments in cancer treatment and transplantation medicine. Only limited diagnostic tools and few antifungals are available, rendering a significant number of invasive fungal infections life threatening. To reduce mortality rates, a better understanding of the infection processes is urgently required. Bioluminescence imaging (BLI) is a powerful tool for such purposes, since it allows visualisation of temporal and spatial progression of infections in real time. BLI has been successfully used to monitor infections caused by various microorganisms, in particular bacteria. However, first studies have also been performed on the fungiCandida albicansandAspergillus fumigatus. Although BLI was, in principle, suitable to study the infection process, some limitations remained. Here, different luciferase systems are introduced, and current approaches are summarised. Finally, suggestions for further improvements of BLI to monitor fungal infections are provided.
Screening Practices of Unaffected People at Familial Risk of Colorectal Cancer
Authors: Ait Ouakrim Driss , Boussioutas Alex , Lockett Trevor , Winship Ingrid , Giles Graham G. , Flander Louisa B. , Keogh Louise , Hopper John L. , Jenkins Mark A.
Published: October 2011

Our objective was to determine screening practices of unaffected people in the general population at moderately increased and potentially high risk of colorectal cancer (CRC) because of their family history of the disease. A total of 1,627 participants in the Australasian Colorectal Cancer Family Registry study were classified into two CRC risk categories, according to the strength of their family history of the disease. We calculated the proportion of participants that adhered to national CRC screening guidelines by age group and for each familial risk category. We carried out a multinomial logistic regression analysis to evaluate the associations between screening and sociodemographic factors. Of the 1,236 participants at moderately increased risk of CRC, 70 (6%) reported having undergone guideline-defined “appropriate” screening, 251 (20%) reported some, but less than appropriate screening, and 915 (74%) reported never having had any CRC screening test. Of the 392 participants at potentially high risk of CRC, three (1%) reported appropriate screening, 140 (36%) reported some, but less than appropriate screening, and 249 (64%) reported never having had any CRC screening test. On average, those of middle age, higher education, and who had resided in Australia longer were more likely to have had screening for CRC. The uptake of recommended screening by unaffected people at the highest familial risk of developing CRC is extremely low. Guidelines for CRC screening are not being implemented in the population. More research is needed to identify the reasons so as to enable development of strategies to improve participation in screening. Cancer Prev Res; 5(2); 240–7. ©2011 AACR.
Status and Significance of CpG Island Methylator Phenotype in Endometrial Cancer
Authors: Zhang Qing-Ying , Yi De-Qing , Zhou Li , Zhang Dong-Hong , Zhou Tai-Mei
Published: October 2011

Background: Endometrial cancer is a common gynecologic malignant disease, but patients with advanced disease have a poor prognosis. The CpG island methylator phenotype (CIMP) involves hypermethylation targeted toward the promoters of multiple genes. Objective: To investigate the role of epigenetic aberration of tumor-related genes in endometrial cancer. Methods: The promoter methylation status of 5 genes was examined in 35 endometrial cancer tissues, 15 matched adjacent normal endometrial tissues (NET) from the same cancer patients, and 22 benign endometria from unaffected patients by methylation-specific PCR. CIMP positivity (CIMP+) was defined as concordant methylation of ≧3 genes. Results: The methylation frequency of promoters for the 5 genes in the cancer tissues ranged from 37% for P16 to 57% for P14. Cancer and benign endometria, but not cancer and adjacent NET, significantly differed in methylation of P14, P16, ER, COX-2 and RASSF1A (p < 0.05). CIMP+ was frequent in cancer and adjacent NET (46 and 47%, respectively; p > 0.05), but absent in benign endometria. Moreover, CIMP+ was significantly correlated with methylation of P16 and COX-2 (r = 0.673 and 0.662, respectively; p < 0.001). Conclusion: CIMP+ is an important and frequent epigenetic event in endometrial cancer or adjacent NET, and may be a biomarker for predicting early carcinogenesis. COX-2 is a good representative gene of CIMP+ in this cancer.
Pregnancy Outcome of Migrant Women Delivering in a Public Institution in Northern Italy
Authors: Zanconato Giovanni , Iacovella Carlotta , Parazzini Fabio , Bergamini Valentino , Franchi Massimo
Published: October 2011

Background/Aim: European societies are facing a wave of incoming immigrants and the needs of a new multiethnic obstetrical population. It remains controversial whether native and immigrant women have equivalent pregnancy outcomes. Methods: Perinatal indicators of the obstetric outcome were monitored in all delivering women during a 5-year period in a large academic public general hospital. We compared rates of preterm deliveries, low birth weight, cesarean section during labor, perineal tears, and fetal acidemia in the native and immigrant parturients. Results: Immigrant women experienced very low birth weight (p < 0.005) and preterm deliveries (p < 0.05), more often than natives did. Among ethnic groups, data singled out Sub-Saharan African women to be at a higher risk for very small premature babies and cesarean section during labor. Conclusions: There are differences in perinatal outcome between immigrant and Italian woman; within the large migrant population, ethnic groups show wide disparities and challenge the health provider differently. Special attention to women at a higher risk may reduce fetal-maternal morbidities.
Thrush – Nightmare of the Foundling Hospitals
Authors: Obladen Michael
Published: October 2011

Before safe artificial nutrition, refrigeration, and microorganisms became known, thrush was a severe and frequently lethal disease in foundling hospitals. Overcrowded and understaffed, these institutions were the ideal breeding ground for this disease. Malnutrition, especially when breastfeeding was denied, contributed to the fatal course. Nosocomial infections and high mortality led to a prejudice against infant hospitals in the late 19th century. Candida albicans was discovered in 1840 when a cooperation at the Paris Foundling Hospital between the Hungarian emigrant David Gruby and the Swede Frederik Berg led to this organism being the first pathogen to be identified. After World War II, Candida infections increased with the use of antibiotics. The disease became less threatening after the development of nystatin, the result of an interdisciplinary cooperation in New York between the microbiologist Elizabeth Hazen and the biochemist Rachel Brown.
Noninvasive Assessment of the Early Transitional Circulation in Healthy Term Infants
Authors: Popat Himanshu , Kluckow Martin
Published: October 2011

Background: The early neonatal circulatory transition usually occurs smoothly but occasionally it is incomplete or reverts to the fetal state of high pulmonary vascular resistance, resulting in significant neonatal morbidity. Objective: To define the normal values for echocardiographic parameters during the early transitional circulation in term infants. Methods: Two-dimensional, M-mode, pulsed and color flow Doppler echocardiography was used to assess healthy term infants in the first 4 h of life. Left and right ventricular outputs (LVO and RVO) and myocardial performance indices (MPI), left ventricular fractional shortening, end-systolic diameter and end-diastolic diameter, ductal size, shunt and peak velocities, tricuspid regurgitation and left pulmonary artery diastolic velocities were documented. Results: A total of 21 normal term infants were assessed with median gestation of 39 weeks, birth weight of 3,470 g and postnatal age of 3 h and 22 min. The median echocardiographic values were LVO 193 ml/kg/min, RVO 216 ml/kg/min, left MPI 0.41, right MPI 0.63, and fractional shortening 29%. The ductus was patent in all 21 infants with a median size of 2.3 mm; ductal flow was bidirectional in 86% with median peak left-to-right velocity of 1.07 m/s. The median left pulmonary artery diastolic velocity was 0.31 m/s and physiological tricuspid regurgitation was present in all infants. Conclusion: This study defines normal values for echocardiographic measurements in healthy term infants during the first 4 h after birth. These normative data may be useful in early identification of infants with abnormal circulatory transition, allowing more rapid determination of cardiovascular dysfunction.
Physical Mapping of Innate Immune Genes, Mucins and Lysozymes, and Other Non-Mucin Proteins in the Tammar Wallaby (Macropus eugenii)
Authors: Edwards M.J. , Hinds L.A. , Deane E.M. , Deakin J.E.
Published: October 2011

Sequencing of the tammar wallaby (Macropus eugenii) genome has the potential to be an extremely valuable resource for investigating evolutionary and developmental aspects of the mammalian immune system. However, the tammar wallaby genome has only been sequenced to a 2-fold depth and consists of small contigs, leaving many sequence gaps, many putative orthologs unpredicted and the location of genes within the genome unknown. In the case of low sequenced genomes, physical maps of genes on chromosomes can help identify specific genes if they map to conserved regions. Genes corresponding to adaptive immunity have been mapped in the tammar wallaby; however, genes corresponding to the innate immune system have not been investigated. We predict 2 types of genes important to the innate immune system, mucins and lysozymes, in the tammar wallaby and compare the predicted peptide sequences and locations of the genes with the South American opossum (Monodelphis domestica) and human. We use fluorescence in situ hybridization to physically map the genes to tammar wallaby chromosomes, demonstrating the importance of identifying and mapping genes when genomes have low sequence coverage. As mucins and lysozymes play protective roles in young animals, we also propose that their immunological role in developing marsupials warrants further investigation.
Ultrastructure of the Membrana Limitans Interna after Dye-Assisted Membrane Peeling
Authors: Brockmann Tobias , Steger Claudia , Westermann Martin , Nietzsche Sandor , Koenigsdoerffer Ekkehart , Strobel Juergen , Dawczynski Jens
Published: October 2011

The purpose of this study was to investigate the ultrastructure of the membrana limitans interna (internal limiting membrane, ILM) and to evaluate alterations to the retinal cell layers after membrane peeling with vital dyes. Twenty-five patients (25 eyes) who underwent macular hole surgery were included, whereby 12 indocyanine green (ICG)- and 13 brilliant blue G (BBG)-stained ILM were analyzed using light, transmission electron and scanning electron microscopy. Retinal cell fragments on the ILM were identified in both groups using immunohistochemistry. Comparing ICG- and BBG-stained membranes, larger cellular fragments were observed at a higher frequency in the BBG group. Thereby, the findings indicate that ICG permits an enhanced separation of the ILM from the underlying retina with less mechanical destruction. A possible explanation might be seen in the known photosensitivity of ICG, which induces a stiffening and shrinkage of the ILM but also generates retinal toxic metabolites.
Right Ventricular Outflow Tract Repair with a Cardiac Biologic Scaffold
Authors: Wainwright John M. , Hashizume Ryotaro , Fujimoto Kazuro L. , Remlinger Nathaniel T. , Pesyna Colin , Wagner William R. , Tobita Kimimasa , Gilbert Thomas W. , Badylak Stephen F.
Published: October 2011

Background: Surgical reconstruction of congenital heart defects is often limited by the nonresorbable material used to approximate normal anatomy. In contrast, biologic scaffold materials composed of resorbable non-cross-linked extracellular matrix (ECM) have been used for tissue reconstruction of multiple organs and are replaced by host tissue. Preparation of whole organ ECM by decellularization through vascular perfusion can maintain much of the native three-dimensional (3D) structure, strength, and tissue-specific composition. A 3D cardiac ECM (C-ECM) biologic scaffold material would logically have structural and functional advantages over materials such as Dacron™ for myocardial repair, but the in vivo remodeling characteristics of C-ECM have not been investigated to date. Methods and Results: A porcine C-ECM patch or Dacron patch was used to reconstruct a full-thickness right ventricular outflow tract (RVOT) defect in a rat model with end points of structural remodeling function at 16 weeks. The Dacron patch was encapsulated by dense fibrous tissue and showed little cellular infiltration. Echocardiographic analysis showed that the right ventricle of the hearts patched with Dacron were dilated at 16 weeks compared to presurgery baseline values. The C-ECM patch remodeled into dense, cellular connective tissue with scattered small islands of cardiomyocytes. The hearts patched with C-ECM showed no difference in the size or function of the ventricles as compared to baseline values at both 4 and 16 weeks. Conclusions: The C-ECM patch was associated with better functional and histomorphological outcomes compared to the Dacron patch in this rat model of RVOT reconstruction.