bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrothermal analysis of spin-transfer-torque random access memory arrays
Authors: Chatterjee Subho , Salahuddin Sayeef , Kumar Satish , Mukhopadhyay Saibal
Published: June 2013

Spin Transfer Torque RAM (STTRAM) is a promising candidate for fast, scalable, high-density, nonvolatile memory in nanometer technology. However, relatively high write current density and small volume of the memory device indicate the possibility of significant self-heating in the STTRAM structure. This article performs a critical analysis of the self-heating induced temperature variations in STTRAM. We perform a 3D finite volume method based study to characterize self-heating effect in a single cell. The analysis is extended for STTRAM arrays by developing a computationally efficient RC compact model based thermal analyzer. The analysis shows that self-heating can results in considerable increase in both steady-state value and transient change in temperature of individual cells. The effect is less pronounced at the array level and depends on the activity level, that is, number of active cells within an array size. The analysis further illustrates that self-heating negatively impacts electrical reliability metrics namely, read margin and detection accuracy; degrades cell performance; and modulates energy dissipation.
On-chip caches built on multilevel spin-transfer torque RAM cells and its optimizations
Authors: Chen Yiran , Wong Weng-Fai , Li Hai , Koh Cheng-Kok , Zhang Yaojun , Wen Wujie
Published: June 2013

It has been predicted that a processor's caches could occupy as much as 90% of chip area a few technology nodes from the current ones. In this article, we investigate the use of multilevel spin-transfer torque RAM (STT-RAM) cells in the design of processor caches. We start with examining the access (read and write) scheme for multilevel cell (MLC) STT-RAM from a circuit design perspective, detailing the read and write circuits. Compared to traditional SRAM caches, a multilevel cell (MLC) STT-RAM cache design is denser, fast, and requires less energy. However, a number of critical architecture-level issues remain to be solved before MLC STT-RAM technology can be deployed in processor caches. We shall offer solutions to the issue of bit encoding as well as tackle the write endurance problem. In particular, the latter has been neglected in previous works on STT-RAM caches. We propose a set remapping scheme that can potentially prolong the lifetime of a MLC STT-RAM cache by 80× on average. Furthermore, a method for recovering the performance that may be lost in some applications due to set remapping is proposed. The impacts of process variations of the MLC STT-RAM cell on the robustness of the memory hierarchy is also discussed, together with various enhancement techniques, namely, ECC and design redundancy.
Optimizing Storage Performance for VM-Based Mobile Computing
Authors: Smaldone Stephen , Gilbert Benjamin , Harkes Jan , Iftode Liviu , Satyanarayanan Mahadev
Published: June 2013

This article investigates the transient use of free local storage for improving performance in VM-based mobile computing systems implemented as thick clients on host PCs. We use the term
TransientPC systems
to refer to these types of systems. The solution we propose, called
TransPart
, uses the higher-performing local storage of host hardware to speed up performance-critical operations. Our solution constructs a virtual storage device on demand (which we call
transient storage
) by borrowing free disk blocks from the host’s storage. In this article, we present the design, implementation, and evaluation of a TransPart prototype, which requires no modifications to the software or hardware of a host computer. Experimental results confirm that TransPart offers low overhead and startup cost, while improving user experience.
Network Formation in the Presence of Contagious Risk
Authors: Blume Lawrence , Easley David , Kleinberg Jon , Kleinberg Robert , Tardos Éva
Published: June 2013

There are a number of domains where agents must collectively form a network in the face of the following trade-off: each agent receives benefits from the direct links it forms to others, but these links expose it to the risk of being hit by a cascading failure that might spread over multistep paths. Financial contagion, epidemic disease, the exposure of covert organizations to discovery, and electrical power networks are all settings in which such issues have been articulated.

Here we formulate the problem in terms of strategic network formation, and provide asymptotically tight bounds on the welfare of both optimal and stable networks. We find that socially optimal networks are, in a precise sense, situated just beyond a phase transition in the behavior of the cascading failures, and that stable graphs lie slightly further beyond this phase transition, at a point where most of the available welfare has been lost. Our analysis enables us to explore such issues as the trade-offs between clustered and anonymous market structures, and it exposes a fundamental sense in which very small amounts of “over-linking” in networks with contagious risk can have strong consequences for the welfare of the participants.
Selling in Exclusive Markets
Authors: Karlin Anna R. , Nguyen C. Thach , Peres Yuval
Published: June 2013

We consider prior-free benchmarks in non-matroid settings. In particular, we show that a very desirable benchmark proposed by Hartline and Roughgarden is too strong, in the sense that no truthful mechanism can compete with it even in a very simple non-matroid setting where there are two exclusive markets and the seller can only sell to agents in one of them. On the other hand, we show that there is a mechanism that competes with a symmetrized version of this benchmark. We further investigate the more traditional best fixed price profit benchmark and show that there are mechanisms that compete with it in any downward-closed settings.
Optimal Auctions with Positive Network Externalities
Authors: Haghpanah Nima , Immorlica Nicole , Mirrokni Vahab , Munagala Kamesh
Published: June 2013

We consider the problem of designing auctions in social networks for goods that exhibit
single-parameter submodular network externalities
in which a bidder’s value for an outcome is a fixed private type times a known submodular function of the allocation of his friends. Externalities pose many issues that are hard to address with traditional techniques; our work shows how to resolve these issues in a specific setting of particular interest. We operate in a Bayesian environment and so assume private values are drawn according to known distributions. We prove that the optimal auction is NP-hard to approximate pointwise, and APX-hard on average. Thus we instead design auctions whose revenue approximates that of the optimal auction. Our main result considers
step-function externalities
in which a bidder’s value for an outcome is either zero, or equal to his private type if at least one friend has the good. For these settings, we provide a
e
/
e
 + 1-approximation. We also give a 0.25-approximation auction for general single-parameter submodular network externalities, and discuss optimizing over a class of simple pricing strategies.
Measuring the degree of face familiarity based on extended NMF
Authors: Zhan Ce , Li Wanqing , Ogunbona Philip
Published: June 2013

Getting familiar with a face is an important cognitive process in human perception of faces, but little study has been reported on how to objectively measure the degree of familiarity. In this article, a method is proposed to quantitatively measure the familiarity of a face with respect to a set of reference faces that have been seen previously. The proposed method models the context-free and context-dependent forms of familiarity suggested by psychological studies and accounts for the key factors, namely exposure frequency, exposure intensity and similar exposure, that affect human perception of face familiarity. Specifically, the method divides the reference set into nonexclusive groups and measures the familiarity of a given face by aggregating the similarities of the face to the individual groups. In addition, the nonnegative matrix factorization (NMF) is extended in this paper to learn a compact and localized subspace representation for measuring the similarities of the face with respect to the individual groups. The proposed method has been evaluated through experiments that follow the protocols commonly used in psychological studies and has been compared with subjective evaluation. Results have shown that the proposed measurement is highly consistent with the subjective judgment of face familiarity. Moreover, a face recognition method is devised using the concept of face familiarity and the results on the standard FERET evaluation protocols have further verified the efficacy of the proposed familiarity measurement.
Learning to walk in virtual reality
Authors: Ruddle Roy A. , Volkova Ekaterina , Bülthoff Heinrich H.
Published: June 2013

This article provides longitudinal data for when participants learned to travel with a walking metaphor through virtual reality (VR) worlds, using interfaces that ranged from joystick-only, to linear and omnidirectional treadmills, and actual walking in VR. Three metrics were used: travel time, collisions (a measure of accuracy), and the speed profile. The time that participants required to reach asymptotic performance for traveling, and what that asymptote was, varied considerably between interfaces. In particular, when a world had tight turns (0.75 m corridors), participants who walked were more proficient than those who used a joystick to locomote and turned either physically or with a joystick, even after 10 minutes of training. The speed profile showed that this was caused by participants spending a notable percentage of the time stationary, irrespective of whether or not they frequently played computer games. The study shows how speed profiles can be used to help evaluate participants' proficiency with travel interfaces, highlights the need for training to be structured to addresses specific weaknesses in proficiency (e.g., start-stop movement), and for studies to measure and report that proficiency.
Ten Years of Building Broken Chips
Authors: Palem Krishna , Lingamneni Avinash
Published: June 2013

Well over a decade ago, many believed that an engine of growth driving the semiconductor and computing industries---captured nicely by Gordon Moore’s remarkable prophecy (Moore’s law)---was speeding towards a dangerous cliff-edge. Ranging from expressions of concern to doomsday scenarios, the exact time when serious hurdles would beset us varied quite a bit---some of the more optimistic warnings giving Moore’s law until. Needless to say, a lot of people have spent time and effort with great success to find ways for substantially extending the time when we would encounter the dreaded cliff-edge, if not avoiding it altogether. Faced with this issue, we started approaching this in a decidedly different manner---one which suggested falling off the metaphorical cliff as a design choice, but in a controlled way. This resulted in devices that could switch and produce bits that are correct, namely of having the intended value, only with a probabilistic guarantee. As a result, the results could in fact be incorrect. Such devices and associated circuits and computing structures are now broadly referred to as inexact designs, circuits, and architectures. In this article, we will crystallize the essence of inexactness dating back to 2002 through two key principles that we developed: (i) that of admitting error in a design in return for resource savings, and subsequently (ii) making resource investments in the elements of a hardware platform proportional to the value of information they compute. We will also give a broad overview of a range of inexact designs and hardware concepts that our group and other groups around the world have been developing since, based on these two principles. Despite not being deterministically precise, inexact designs can be significantly more efficient in the energy they consume, their speed of execution, and their area needs, which makes them attractive in application contexts that are resilient to error. Significantly, our development of inexactness will be contrasted against the rich backdrop of traditional approaches aimed at realizing reliable computing from unreliable elements, starting with von Neumann’s influential lectures and further developed by Shannon-Weaver and others.
Exploiting Timing Error Resilience in Processor Architecture
Authors: Sartori John , Kumar Rakesh
Published: June 2013

Escalating variations in modern CMOS designs have become a threat to Moore’s law. In light of the increasing costs of standard worst-case design practices, timing speculation has become a popular approach for dealing with static and dynamic non-determinism and increasing yield. Timing speculative architectures allow conservative guardbands to be relaxed, increasing efficiency at the expense of occasional errors, which are corrected or tolerated by an error resilience mechanism. Previous work has proposed circuit- or design-level optimizations that manipulate the error rate behavior of a design to increase the efficiency of timing speculation. In this article, we investigate whether architectural optimizations can also manipulate error rate behavior to significantly increase the effectiveness of timing speculation. To this end, we demonstrate how error rate behavior indeed depends on processor architecture and that architectural optimizations can be used to manipulate the error rate behavior of a processor. Using timing speculation-aware architectural optimizations, we demonstrate enhanced overscaling and up to 29% additional energy savings for processors that employ Razor-based timing speculation.
Half-Wits
Authors: Salajegheh Mastooreh , Wang Yue , Jiang Anxiao (Andrew) , Learned-Miller Erik , Fu Kevin
Published: June 2013

This work analyzes the stochastic behavior of writing to embedded flash memory at voltages lower than recommended by a microcontroller’s specifications in order to reduce energy consumption. Flash memory integrated within a microcontroller typically requires the entire chip to operate on a common supply voltage almost twice as much as what the CPU portion requires. Our software approach allows the flash memory to tolerate a lower supply voltage so that the CPU may operate in a more energy-efficient manner. Energy-efficient coding algorithms then cope with flash memory writes that behave unpredictably.

Our software-only coding algorithms (
in-place writes, multiple-place writes, RS-Berger codes
, and
slow writes
) enable reliable storage at low voltages on unmodified hardware by exploiting the electrically cumulative nature of half-written data in write-once bits. For a sensor monitoring application using the MSP430, coding with in-place writes reduces the overall energy consumption by 34%. In-place writes are competitive when the time spent on low-voltage operations such as computation are at least four times greater than the time spent on writes to flash memory. Our evaluation shows that tightly maintaining the digital abstraction for storage in embedded flash memory comes at a significant cost to energy consumption with minimal gain in reliability. We find our techniques most effective for embedded workloads that have significant duty cycling, rare writes, or energy harvesting.
Probabilistic Temporal Logic Falsification of Cyber-Physical Systems
Authors: Abbas Houssam , Fainekos Georgios , Sankaranarayanan Sriram , Ivančić Franjo , Gupta Aarti
Published: June 2013

We present a Monte-Carlo optimization technique for finding system behaviors that falsify a metric temporal logic (MTL) property. Our approach performs a random walk over the space of system inputs guided by a robustness metric defined by the MTL property. Robustness is guiding the search for a falsifying behavior by exploring trajectories with smaller robustness values. The resulting testing framework can be applied to a wide class of cyber-physical systems (CPS). We show through experiments on complex system models that using our framework can help automatically falsify properties with more consistency as compared to other means, such as uniform sampling.
Energy- and Thermal-Aware Video Coding via Encoder/Decoder Workload Balancing
Authors: Forte Domenic , Srivastava Ankur
Published: June 2013

Video coding and compression are essential components of multimedia services but are known to be computationally intensive and energy demanding. Traditional video coding paradigms, predictive and distributed video coding (PVC and DVC), result in excessive computation at either the encoder (PVC) or decoder (DVC). Several recent papers have proposed a hybrid PVC/DVC codec which shares the video coding workload between encoder and decoder. In this article, we propose a controller for such hybrid coders that considers energy and temperature to dynamically split the coding workload of a system comprised of one encoder and one decoder. We also present two heuristic algorithms for determining safe operating temperatures in the controller solution: (1) stable state thermal modeling algorithm, which focuses on long term temperatures, and (2) transient thermal modeling algorithm, which is better for short-term thermal behavior. Results show that the proposed algorithms result in more balanced energy utilization, improve overall system lifetime, and reduce operating temperatures when compared to strictly PVC and DVC systems.
Energy-efficient data dissemination using beamforming in wireless sensor networks
Authors: Feng Jing , Lu Yung-Hsiang , Jung Byunghoo , Peroulis Dimitrios , Hu Y. Charlie
Published: June 2013

Energy conservation is essential in Wireless Sensor Networks (WSNs) because of limited energy in nodes' batteries. Collaborative beamforming uses multiple transmitters to form antenna arrays; the electromagnetic waves from these antenna arrays can create constructive interferences at the receiver and increase the transmission distance. Each transmitter can use lower power and save energy, since the energy consumption is spread over multiple transmitters. Each beamforming transmission requires multiple collaborative transmitters. Repetitively using the same transmitters will deplete their energy and create coverage holes in the sensing area. To prevent holes, energy should be balanced by using different transmitters. This article investigates the factors that can affect the energy consumption and network lifetime when using beamforming. We present an algorithm for selecting the transmitters in order to prolong the network lifetime. Compared with an existing beamforming transmitters scheduling algorithm, our algorithm doubles the network lifetime. When compared with direct transmission or multihop transmissions towards a receiver far away from the sensing area, our approach can increase the network's lifetime substantially.
Constraint centric scheduling guide
Authors: Sartin-Tarm Michael , Nowatzki Tony , De Carli Lorenzo , Sankaralingam Karthikeyan , Estan Cristian
Published: June 2013

The advent of architectures with software-exposed resources (Spatial Architectures) has created a demand for universally applicable scheduling techniques. This paper describes our generalized spatial scheduling framework, formulated with Integer Linear Programming, and specifically accomplishes two goals. First, using the "Simple" architecture, it illustrates how to use our open-source tool to create a customized scheduler and covers problem formulation with ILP and GAMS. Second, it summarizes results on the application to three real architectures (TRIPS,DySER,PLUG), demonstrating the technique's practicality and competitiveness with existing schedulers.
Systematic evaluation of workload clustering for extremely energy-efficient architectures
Authors: Guha Apala , Zhang Yao , ur Rasool Raihan , Chien Andrew A.
Published: June 2013

Chip power consumption has reached its limits, leading to the flattening of single-core performance. We propose the 10x10 processor, a federated heterogeneous multi-core architecture, where each core is an ensemble of u-engines (micro-engines, similar to accelerators) specialized for different workload groups to achieve dramatically higher energy efficiency. The u-engines collectively target the entire general-purpose workload space.

The problem we study in this article is selecting the set of workloads that each u-engine should be customized for. For this problem we study the computation structure of a wide variety of workloads and cluster together workloads with similar computation structures, the idea being that each u-engine will be customized for the compute structures exhibited by a particular cluster. The constraint on this problem is the silicon budget of a processor. Lower silicon budgets accommodate fewer uengines and require individual u-engines to target larger segments of the workload space which leads to lower energy efficiency benefits from customization, because there is more variation among the compute structures making up each cluster. Therefore, we also study how workload coverage and benefit can be maximized for a given silicon budget.

We study a broad general-purpose workload that includes 34 codes from 6 benchmark suites, identifying the most frequent functions, and clustering them based on two sets of instruction usage features (high-resolution and low-resolution) into 8, 16, 32, 64, 128 clusters respectively. We develop abstract metrics (coverage and weighted customization benefit) to evaluate the clusters. We show significant potential payoffs with four benefit models: 2-3x (square root model), 4-10x (linear model), 12-24x (quadratic model), and 22-26x (cubic model).
FPGA implementation of a novel DCT architecture reducing constant cosine terms
Authors: Pal Santanu , Sinha Amitabha , Biswas Pijush
Published: June 2013

This paper presents a new scalable architecture for Discrete Cosine Transform (DCT). In contrast to the conventional DCT architecture, the proposed architecture reduces the number of constant cosine terms using the matrix transposition and symmetry property. This in turn, considerably reduces the computation time. The architecture is scalable and it can be extended to support any transform length. The architecture was validated on Xilinx Vertex-4 FPGA.
A new non-exact aho-corasick framework for ECG classification
Authors: Tseng Kuo-Kun , Zeng Fu-Fu , Huang Huang-Nan , Liu Yiming , Pan Jeng-Shyang , Ip W. H. , Wu C. H.
Published: June 2013

The Aho-Corasick (AC) algorithm is a popular and useful exact string matching algorithm for text searching and deep packet inspection. However, it has seldom been used for non-exact classification or identification. We propose a novel framework to make use of AC for non-exact matching in the ECG identification. The AC classification (ACC) algorithm converts ECG waveforms into several short patterns for AC, and decides the identification result by AC matched counting value. In our experiments, the results are surprisingly good and superior to previous algorithms. So, we designed an AC algorithm application for non-exact classification with high accuracy. Meanwhile, ACC inherits the advantage from AC of being capable of handling a large pattern set with linear time complexity.
High performance MAC unit for DSP and cryptographic applications
Authors: Maitra Subhashis , Sinha Amitabha
Published: June 2013

Multiplication and addition are the basic arithmetic operation used in Digital Signal Processing (DSP) for coefficient multiplication, scalar point multiplication in Elliptic Curve Cryptography (ECC) and in other fields. Multiplications are basically a shift and add operation. However, there are many different variations on how to do it. Some are more suitable to implement on FPGA than others. However time complexities and hardware complexities are the major issues in designing a multiplier unit. There are different multiplication algorithms in current technology. Hardware complexities in some design are more than time complexities whereas in some other design time complexities are more. However there must be a tradeoff between these two types of methodology. This paper will discuss a brief idea how a tradeoff can be achieved. Experimental results that have discussed here and the architecture based on the proposed algorithm shows it's novelty. Applications of the proposed algorithm on DSP and ECC have been dealt here clearly.
Computational geometry column 56
Authors: Dumitrescu Adrian , Jiang Minghui
Published: June 2013

This column is devoted to maximum (respectively, maximum weight) independent set problems in geometric intersection graphs. We illustrate with one example in each class:

(I) The following question was asked by T. Rado in 1928: What is the largest number
c
such that, for any finite set
F
of axis-parallel squares in the plane, there exists an independent subset
I
⊆
F
of pairwise disjoint squares with total area at least
c
times the union area of the squares.

(II) The following question was asked by Erdös in 1983: What is the largest number
H
=
H
(
n
) with the property that every set of
n
non-overlapping unit disks in the plane has an independent subset with at least
H
members?
Important role of ventromedial hypothalamic carnitine palmitoyltransferase-1a in the control of food intake
Authors: Gao Su , Serra Dolors , Keung Wendy , Hegardt Fausto G. , Lopaschuk Gary D.
Published: June 2013

Carnitine palmitoyltransferase-1 (CPT-1) liver isoform, or CPT-1a, is implicated in CNS control of food intake. However, the exact brain nucleus site(s) in mediating this action of CPT-1a has not been identified. In this report, we assess the role of CPT-1a in hypothalamic ventromedial nucleus (VMN). We stereotaxically injected an adenoviral vector containing CPT-1a coding sequence into the VMN of rats to induce overexpression and activation of CPT-1a. The VMN-selective activation of CPT-1a induced an orexigenic effect, suggesting CPT-1a in the VMN is involved in the central control of feeding. Intracerebroventricular administration of etomoxir, a CPT-1 inhibitor, decreases food intake. Importantly, in the animals with VMN overexpression of a CPT-1a mutant that antagonizes the CPT-1 inhibition by etomoxir, the anorectic response to etomoxir was attenuated. This suggests that VMN is involved in mediating the anorectic effect of central inhibition of CPT-1a. In contrast, arcuate nucleus (Arc) overexpression of the mutant did not alter etomoxir-induced inhibition of food intake, suggesting that Arc CPT-1a does not play significant roles in this anorectic action. Furthermore, in the VMN, CPT-1a appears to act downstream of hypothalamic malonyl-CoA action of feeding. Finally, we show that in the VMN CPT-1 activity was altered in concert with fasting and refeeding states, supporting a physiological role of CPT-1a in mediating the control of feeding. All together, CPT-1a in the hypothalamic VMN appears to play an important role in central control of food intake. VMN-selective modulation of CPT-1a activity may therefore be a promising strategy in controlling food intake and maintaining normal body weight.
Process Improvement by Eliminating Mixing of Whole Blood Units after an Overnight Hold Prior to Component Production Using the Buffy Coat Method
Authors: Mastronardi Cherie , Schubert Peter , Levin Elena , Bhakta Varsha , Yi Qi-Long , Hansen Adele , Stewart Tamiko , Jenkins Craig , Lefresne Wanda , Sheffield William , Acker Jason P.
Published: June 2013

The elimination of a thorough manual mixing of whole blood (WB) which takes place following the overnight hold, but before the first centrifugation step, during buffy coat component production at Canadian Blood Services (CBS) was investigated. WB was pooled after donation and split. Pairs of platelet, red blood cell (RBC), and plasma components were produced, with half using the standard method and half using a method in which the mixing step was eliminated. Quality assessments included yield, pH, CD62P expression and morphology for platelets, hemoglobin, hematocrit, hemolysis, and supernatant K+for RBCs, and volume and factor VIII activity levels for plasma. All components, produced using either method, met CBS quality control criteria. There were no significant differences in platelet yield between components produced with and without mixing. A significant difference was seen for RBC hemolysis at expiry (P=0.03), but for both groups, levels met quality control requirements. Noninferiority of components produced without mixing was confirmed for all parameters. Manual mixing is laborious and has a risk of repetitive strain for production staff and its significance is unclear. Elimination of this step will improve process efficiencies without compromising quality.
Metabolic Disturbance in PCOS: Clinical and Molecular Effects on Skeletal Muscle Tissue
Authors: Silva Dantas Wagner , Gualano Bruno , Patrocínio Rocha Michele , Roberto Grimaldi Barcellos Cristiano , dos Reis Vieira Yance Viviane , Miguel Marcondes José Antonio
Published: June 2013

Polycystic ovary syndrome is a complex hormonal disorder affecting the reproductive and metabolic systems with signs and symptoms related to anovulation, infertility, menstrual irregularity and hirsutism.
Skeletal muscle plays a vital role in the peripheral glucose uptake. Since PCOS is associated with defects in the activation and pancreatic dysfunction of β‐cell insulin, it is important to understand the molecular mechanisms of insulin resistance in PCOS. Studies of muscle tissue in patients with PCOS reveal defects in insulin signaling. Muscle biopsies performed during euglycemic hyperinsulinemic clamp showed a significant reduction in glucose uptake, and insulin‐mediated IRS‐2 increased significantly in skeletal muscle. It is recognized that the etiology of insulin resistance in PCOS is likely to be as complicated as in type 2 diabetes and it has an important role in metabolic and reproductive phenotypes of this syndrome. Thus, further evidence regarding the effect of nonpharmacological approaches (e.g., physical exercise) in skeletal muscle of women with PCOS is required for a better therapeutic approach in the management of various metabolic and reproductive problems caused by this syndrome.
Unstable Manifolds of Continuous Self-Mappings
Authors: Lu Tianxiu , Zhu Peiyong
Published: June 2013

Unstable manifolds of continuous self-mappings on completely densely ordered linear ordered topological spaces (CDOLOTS) are discussed. Let f be a continuous self-map. First, the interval with endpoints of two adjacent fixed points is contained in the unilateral unstable manifold of one of the endpoints. Then, by using the above conclusion, we prove that periodic points of f not belong to the unstable manifold of their iteration points of fn (for some n∈ℕ), unless the iteration points are themselves.
On the Mean Residual Life Function and Stress and Strength Analysis under Different Loss Function for Lindley Distribution
Authors: Ali Sajid
Published: June 2013

Purpose. Mathematical properties of Lindley distribution are derived under different loss functions. These properties include mean residual life function, Lorenz curve, stress and strength characteristic, and their respective posterior risk via simulation scheme.Methodology. Bayesian approach is used for the reliability characteristics. Results are compared on the basis of posterior risk.Findings. Using prior information on the parameter of Lindley distribution, Bayes estimates for reliability characteristics are compared under different loss functions.Practical Implications. Since Lindley distribution is a mixture of gamma and exponential distribution, so Bayesian estimation of reliability characteristics will have a great implication in reliability theory.Originality. A real life application to waiting time data at the bank is also described for the developed procedures. This study is useful for researcher and practitioner in reliability theory.
Dynamic Characters of Stiffened Composite Conoidal Shell Roofs with Cutouts: Design Aids and Selection Guidelines
Authors: Sahoo Sarmila
Published: June 2013

Dynamic characteristics of stiffened composite conoidal shells with cutout are analyzed in terms of the natural frequency and mode shapes. A finite element code is developed for the purpose by combining an eight-noded curved shell element with a three-noded curved beam element. The code is validated by solving benchmark problems available in the literature and comparing the results. The size of the cutouts and their positions with respect to the shell centre are varied for different edge constraints of cross-ply and angle-ply laminated composite conoids. The effects of these parametric variations on the fundamental frequencies and mode shapes are considered in details. The results furnished here may be readily used by practicing engineers dealing with stiffened composite conoids with cutouts central or eccentric.
Long Noncoding RNA HOTAIR Is Associated with Motility, Invasion, and Metastatic Potential of Metastatic Melanoma
Authors: Tang Lihua , Zhang Wei , Su Bing , Yu Bo
Published: June 2013

Metastatic melanoma, the primary cause of skin cancer-related death, warrants new therapeutic approaches that target the regulatory machinery at molecular level. While long noncoding RNAs (lncRNAs) are dysregulated in a number of cancer types, limited data are available on the expression and function of lncRNAs in melanoma metastasis. The primary objective of this study was to investigate the role of 6 metastasis-related lncRNAs in pairs of primary melanoma and matched lymph node metastatic tissues. Among the tested lncRNAs, HOTAIR was the most highly expressed in lymph node metastasis. The role of HOTAIR in melanoma cell motility and invasion was further evaluated by knocking down HOTAIR with siRNAs. Knockdown of HOTAIR resulted in the reduction of motility and invasion of human melanoma cell line A375, as assessed by wound healing assay and Matrigel-based invasion assay. siHOTAIR also suppressed the degradation of gelatin matrix, suggesting that HOTAIR promotes gelatinase activity. Together, our study shows that HOTAIR is overexpressed in metastatic tissue, which is associated with the ability of HOTAIR to promote melanoma cell motility and invasion. These data indicate that lncRNAs may be involved in the metastasis of melanoma and provide support for further evaluation of lncRNAs in melanoma.
Profiling of Phytochemicals in Tissues from Sclerocarya birrea by HPLC-MS and Their Link with Antioxidant Activity
Authors: Russo Daniela , Kenny Owen , Smyth Thomas J. , Milella Luigi , Hossain Mohammad B. , Diop Moussoukhoye Sissokho , Rai Dilip K. , Brunton Nigel P.
Published: June 2013

High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was employed to investigate the differences in phytochemicals in roots, bark, and leaf of Sclerocarya birrea (marula) for methanol and water extracts that exhibited the best antioxidant activities. As many as 36 compounds were observed in the extracts of these tissues of which 27 phenolic compounds were tentatively identified. The HPLC-MS/MS results showed flavonoid glycosides were prominent in leaf extracts while the galloylated tannins were largely in bark and root extracts. Four flavonoid glycosides that were reported for the first time in the marula leaf have been identified. The HPLC-MS/MS studies also illustrated different degrees (highest degree = 3) of oligomerisation and galloylation of tannins in the bark and root extracts.
Biochemical Methane Potential of Agro Wastes
Authors: Prabhudessai Vidhya , Ganguly Anasuya , Mutnuri Srikanth
Published: June 2013

The focus of our work is on anaerobic digestion of locally available agro wastes like coconut oil cake, cashew apple waste, and grass from lawn cuttings. The most productive agro waste, in terms of methane yield, was coconut oil cake and grass. The results showed that the initial volatile solids concentration significantly affected the biogas production. The methane yield from coconut oil cake was found to be 383 ml CH4/g VS and 277 ml CH4/g VS added at 4 and 4.5 g VS/l. In case of grass the biogas production increased with increasing VS concentrations with methane yield of 199, 250, 256, 284, and 332 ml CH4/g VS at 3, 3.5, 4, 4.5, and 5.0 g VS/l. For cashew apple waste single-stage fermentation inhibited biogas production. However, phase separation showed methane yield of 60.7 ml CH4/g VS and 64.6 ml CH4/g VS at 3.5 and 4.0 g VS/l, respectively. The anaerobic biodegradability of coconut oil cake was evaluated in fed batch mode in a 5 L anaerobic reactor at 4 g VS/L per batch, and the maximum methane yield was found to be 320 ml CH4/g VS.
Coefficient Estimates and Other Properties for a Class of Spirallike Functions Associated with a Differential Operator
Authors: Orhan Halit , Răducanu Dorina , Çağlar Murat , Bayram Mustafa
Published: June 2013

For , , , , and , a new class of analytic functions defined by means of the differential operator is introduced. Our main object is to provide sharp upper bounds for Fekete-Szegö problem in . We also find sufficient conditions for a function to be in this class. Some interesting consequences of our results are pointed out.
On Parameters Estimation of Lomax Distribution under General Progressive Censoring
Authors: Al-Zahrani Bander , Al-Sobhi Mashail
Published: June 2013

We consider the estimation problem of the probabilityS=P(Y<X)for Lomax distribution based on general progressive censored data. The maximum likelihood estimator and Bayes estimators are obtained using the symmetric and asymmetric balanced loss functions. The Markov chain Monte Carlo (MCMC) methods are used to accomplish some complex calculations. Comparisons are made between Bayesian and maximum likelihood estimators via Monte Carlo simulation study.
Generation of Multiple Focal Hole Segments Using Double-Ring Shaped Azimuthally Polarized Beam
Authors: Lalithambigai K. , Saraswathi R. C. , Anbarasan P. M. , Rajesh K. B. , Jaroszewicz Z.
Published: June 2013

We investigated the focusing properties of a double-ring-shaped azimuthally polarized beam tightly focused with a high NA lens and a binary phase filter. We observe that by using 3 belts and 5 belts binary phase filters novel focal patterns including splitting of focal rings and multiring focus are obtained. We also found that a suitably designed phase structure can shift the focal rings along optical axis. The author expects such investigation is worthwhile for optical manipulation and material processing technologies.
On -Cogenerated Commutative Unital -Algebras
Authors: Momtahan Ehsan
Published: June 2013

Gelfand-Naimark's theorem states that every commutative -algebra is isomorphic to a complex valued algebra of continuous functions over a suitable compact space. We observe that for a completely regular space , is dense--separable if and only if is -cogenerated if and only if every family of maximal ideals of with zero intersection has a subfamily with cardinal number less than and zero intersection. This gives a simple characterization of -cogenerated commutative unital -algebras via their maximal ideals.
Necessary and Sufficient Conditions for the Existence of a Positive Definite Solution for the Matrix Equation
Authors: El-Shazly Naglaa M.
Published: June 2013

In this paper necessary and sufficient conditions for the matrix equation to have a positive definite solution are derived, where , is an identity matrix, are nonsingular real matrices, and is an odd positive integer. These conditions are used to propose some properties on the matrices , . Moreover, relations between the solution and the matrices are derived.
Current Concepts in the Biopsy of Musculoskeletal Tumors
Authors: Errani Costantino , Traina Francesco , Perna Fabrizio , Calamelli Carlotta , Faldini Cesare
Published: June 2013

In the management of bone and soft tissue tumors, accurate diagnosis, using a combination of clinical, radiographic, and histological data, is critical to optimize outcome. On occasion, diagnosis can be made by careful history, physical examination, and images alone. However, the ultimate diagnosis usually depends on histologic analysis by an experienced pathologist. Biopsy is a very important and complex surgery in the staging process. It must be done carefully, so as not to adversely affect the outcome. Technical considerations include proper location and orientation of the biopsy incision and meticulous hemostasis. It is necessary to obtain tissue for a histological diagnosis without spreading the tumor and so compromise the treatment. Furthermore, the surgeon does not open compartmental barriers, anatomic planes, joint space, and tissue area around neurovascular bundles. Nevertheless, avoid producing a hematoma. Biopsy should be carefully planned according to the site and definitive surgery and should be performed by an orthopedic surgeon with an experience in musculoskeletal oncology who will perform the definitive surgery. Improperly done, it can complicate patient care and sometimes even eliminate treatment options. Different biopsy techniques are suitable: fine‐needle aspiration, core‐needle biopsy, and incisional biopsy. The choice of biopsy depends on the size, the location of the lesion, and the experience of the pathologist.
Stability and Accuracy Assessment of Identification of Traditional Chinese Materia Medica Using DNA Barcoding: A Case Study on Flos Lonicerae Japonicae
Authors: Hou Dianyun , Song Jingyuan , Shi Linchun , Ma Xiaochong , Xin Tianyi , Han Jianping , Xiao Wei , Sun Zhiying , Cheng Ruiyang , Yao Hui
Published: June 2013

DNA barcoding is a novel molecular identification method that aids in identifying traditional Chinese materia medica using traditional identification techniques. However, further study is needed to assess the stability and accuracy of DNA barcoding. Flos Lonicerae Japonicae, a typical medicinal flower, is widely used in China, Korea, and other Southeast Asian countries. However, Flos Lonicerae Japonicae and its closely related species have been misused and traded at varying for a wide range of prices. Therefore, Flos Lonicerae Japonicae must be accurately identified. In this study, the ITS2 andpsbA-trnHregions were amplified by polymerase chain reaction (PCR). Sequence assembly was performed using CodonCode Aligner V 3.5.4. The intra- versus inter-specific variations were assessed using six metrics and “barcoding gaps.” Species identification was conducted using BLAST1 and neighbor-joining (NJ) trees. Results reveal that ITS2 andpsbA-trnHexhibited an average intraspecific divergence of 0.001 and 0, respectively, as well as an average inter-specific divergence of 0.0331 and 0.0161. The identification efficiency of ITS2 andpsbA-trnHevaluated using BLAST1 was 100%. Flos Lonicerae Japonicae was formed into one clade through the NJ trees. Therefore, Flos Lonicerae Japonicae can be stably and accurately identified through the ITS2 andpsbA-trnHregions, respectively.
Deciphering the Intracellular Fate ofPropionibacterium acnesin Macrophages
Authors: Fischer Natalie , Mak Tim N. , Shinohara Debika Biswal , Sfanos Karen S. , Meyer Thomas F. , Brüggemann Holger
Published: June 2013

Propionibacterium acnesis a Gram-positive bacterium that colonizes various niches of the human body, particularly the sebaceous follicles of the skin. Over the last years a role of this common skin bacterium as an opportunistic pathogen has been explored. Persistence ofP. acnesin host tissue has been associated with chronic inflammation and disease development, for example, in prostate pathologies. This study investigated the intracellular fate ofP. acnesin macrophages after phagocytosis. In a mouse model ofP. acnes-induced chronic prostatic inflammation, the bacterium could be detected in prostate-infiltrating macrophages at 2 weeks postinfection. Further studies performed in the human macrophage cell line THP-1 revealed intracellular survival and persistence ofP. acnesbut no intracellular replication or escape from the host cell. Confocal analyses of phagosome acidification and maturation were performed. Acidification ofP. acnes-containing phagosomes was observed at 6 h postinfection but then lost again, indicative of cytosolic escape ofP. acnesor intraphagosomal pH neutralization. No colocalization with the lysosomal markers LAMP1 and cathepsin D was observed, implying that theP. acnes-containing phagosome does not fuse with lysosomes. Our findings give first insights into the intracellular fate ofP. acnes; its persistency is likely to be important for the development ofP. acnes-associated inflammatory diseases.
On the Use of the K-Chart for Phase II Monitoring of Simple Linear Profiles
Authors: Gani Walid , Limam Mohamed
Published: June 2013

Control charts for monitoring linear profiles are used to control quality processes which are characterized by a relationship between a response variable and one or more explanatory variables. In the literature, the majority of control charts deal with phase II analysis of linear profiles, where the objective is to assess the performance of control charts in detecting shifts in the parameters of linear profiles. Recently, the kernel distance-based multivariate control chart, also known as the K-chart, has received much attention as a promising nonparametric control chart with high sensitivity to small shifts in the process. Despite its numerous advantages, no work has proposed the use of the K-chart for monitoring simple linear profiles and that serves the motivation for this paper. This paper proposes the use of the K-chart for monitoring simple linear profiles. A benchmark example is used to show the construction methodology of the K-chart for simultaneously monitoring the slope and intercept of linear profile. In addition, performance of the K-chart in detecting out-of-control profiles is assessed and compared with traditional control charts. Results demonstrate that the K-chart performs better than the T2 control chart, EWMA control chart, and R-chart under small shift in the slope.
Individual-, Family-, Community-, and Policy-Level Impact of a School-Based Cardiovascular Risk Detection Screening Program for Children in Underserved, Rural Areas: The CARDIAC Project
Authors: Cottrell Lesley , John Collin , Murphy Emily , Lilly Christa L. , Ritchie Susan K. , Elliott Eloise , Minor Valerie , Neal William A.
Published: June 2013

The Coronary Artery Risk Detection In Appalachian Communities (CARDIAC) Project has screened more than 80,000 children (10–12 years) for cardiovascular and diabetes risk factors over the past 15 years. Simultaneous referral and intervention efforts have also contributed to the overall program impact. In this study, we examined evidence of programmatic impact in the past decade at the individual, family, community, and policy levels from child screening outcomes, referral rates, participation in subsequent services, and policies that embed the activities of the project as a significant element. Within this period of time, fifth-grade overweight and obesity rates were maintained at a time when rates elsewhere increased. 107 children were referred for additional screening and treatment for probable familial hypercholesterolemia (FH); 82 family members were subsequently screened in family-based screening efforts. 58 grants were distributed throughout the state for community-appropriate obesity intervention. A state wellness policy embedded CARDIAC as the method of assessment and national child cholesterol screening guidelines were impacted by CARDIAC findings. The sustainability and successful impact of this school-based program within a largely underserved, rural Appalachian state are also discussed.