bluuebunny/crossref_metadata_2025 huggingface dataset:
GROUP EXTENSIONS OVER INFINITE WORDS
Authors: DIEKERT VOLKER , MYASNIKOV ALEXEI
Published: October 2012

Non-Archimedean words have been introduced as a new type of infinite words which can be investigated through classical methods in combinatorics on words due to a length function. The length function, however, takes values in the additive group of polynomials ℤ[t] (and not, as traditionally, in ℕ), which yields various new properties. Non-Archimedean words allow to solve a number of interesting algorithmic problems in geometric and algorithmic group theory. There is also a connection to logic and the first-order theory in free groups (Tarski Problems).

In the present paper we provide a general method to use infinite words over a discretely ordered abelian group as a tool to investigate certain group extensions for an arbitrary group G. The central object is a group E (A, G) which is defined in terms of a non-terminating, but confluent rewriting system. The groupG as well as some natural HNN-extensions of G embed into E (A, G) (and still "behave like" G), which makes it interesting to study its algorithmic properties. In order to show that every group G embeds into E (A, G) we combine methods from combinatorics on words, string rewriting and group theory.
SOME LANGUAGES RECOGNIZED BY TWO-WAY FINITE AUTOMATA WITH QUANTUM AND CLASSICAL STATES
Authors: ZHENG SHENGGEN , QIU DAOWEN , LI LVZHOU
Published: October 2012

Two-way finite automata with quantum and classical states (2QCFA) were introduced by Ambainis and Watrous, and it was shown that 2QCFA have superiority over two-way probabilistic finite automata (2PFA) for recognizing some non-regular languages such as the language Leq = {anbn ∣ n ∈ N} and the palindrome language Lpal = {w ∈ {a,b}* ∣ w=wR}, where xR is x in the reverse order. It is interesting to find more languages like these that witness the superiority of 2QCFA over 2PFA. In this paper, we consider the language Lm = {xcy ∣ ∑ = {a,b,c},x,y ∈ {a,b}*, ∣x∣ = ∣y∣} that is similar to the middle language Lmiddle = {xay ∣ x,y ∈ {a,b}*, ∣x∣ = ∣y∣}. We prove that the language Lm show that Lm can be recognized by 2PFA with bounded error, but only in exponential expected time. Thus Lm is another witness of the fact that 2QCFA are more powerful than their classical counterparts.
PROPENSITY FOR MINERALIZATION IN VOLCANOES — EVIDENCE FROM MELT INCLUSIONS
Authors: REYES AGNES G. , TROMPETTER WILLIAM J. , GRAHAM IAN J.
Published: October 2012

Rocks and melt inclusions (MI) from 11 volcanic centers of the Kermadec-Tofua arc, in the South West Pacific, were petrographically studied prior to chemical analysis under the ion beam. The abundance of MI with daughter minerals are volcano-specific with the most abundant found in "U", Putoto, and Hinepuia volcanoes where >50% of MI contain daughter minerals. The B , Li , Cl and S contents in MI generally increase with the silica content of the rock. Fe , Ni , Mn , Cu and Zn are common in MI of all rock types but Mo , Hg and Cu have the highest concentrations in dacite-rhyodacites. The highest concentrations of B , Ti , V , Fe , Co and Mo occur in plagioclase MI; S , Ni , Ge and Hg in pyroxene MI; Cl and Li in quartz MI; and Cu , Zn and M in hornblende MI. Different ore-forming components in volcanic rocks can be correlated with rock composition, Cl/S and B/S of the melts, the presence and abundance of mineral sinks for various elements and the occurrence of hydrothermally altered rock at depth and on the seafloor.
MOVEMENT OF HEAVY ELEMENTS IN PLANTS BY MEANS OF A STANDARD-FREE METHOD FOR LIVING PLANTS IN IN-AIR PIXE
Authors: SERA K. , TERASAKI K. K. , SASAKI T. , GOTO S. , TAKAHASHI C. , SAITOH Y.
Published: October 2012

The method, which was developed by our group, enables us to perform quantitative analysis of living plants. It has been applied to investigate the transport of heavy elements such as germanium, gallium, bromine and arsenic in plants. These heavy elements are transported to the leaf through vascular vessel, and changes of their concentration with elapsed time after absorption could be clearly observed. It was confirmed that the movement depends on elements, on the manner of absorption and on the states of plant growth. In addition to the movement of supplied elements, some elements in the plant show interesting changes in response to proton irradiation. It was found that the method is quite effective for examining elemental movement in living plants.
REAL AND COMPLEX SUPERSYMMETRIC d = 1 SIGMA MODELS WITH TORSIONS
Authors: FEDORUK S. A. , IVANOV E. A. , SMILGA A. V.
Published: October 2012

We derive and discuss, at both the classical and quantum levels, generalized [Formula: see text] supersymmetric quantum mechanical sigma models describing the motion over an arbitrary real or an arbitrary complex manifold with extra torsions. We analyze the relevant vacuum states to make explicit the fact that their number is not affected by adding the torsion terms.
ON CROSSED DOUBLE BIPRODUCT
Authors: MA TIANSHUI , JIAO ZHENGMING , SONG YANAN
Published: October 2012

Let H be a bialgebra. Let σ : H ⊗ H → A be a linear map, where A is a left H-comodule coalgebra, and an algebra with a left H-weak action. Let B be a right H-module algebra and also a comodule coalgebra. In this paper, we provide necessary and sufficient conditions for the one-sided crossed product algebra A#σ H # B and the two-sided smash coproduct coalgebra A × H × B to form a bialgebra, which we call the crossed double biproduct. Majid's double biproduct is recovered from this. Moreover, necessary and sufficient conditions are given for Brzeziński's crossed product equipped with the smash coproduct coalgebra structure to be a bialgebra. The celebrated Radford's biproduct in [The structure of Hopf algebra with a projection, J. Algebra92 (1985) 322–347], the unified product defined by Agore and Militaru in [Extending structures II: The quantum version, J. Algebra336 (2011) 321–341] and the Wang–Jiao–Zhao's crossed product in [Hopf algebra structures on crossed products Comm. Algebra26 (1998) 1293–1303] are all derived as special cases.
FINITE GROUPS WITH THE MAXIMAL PERMUTIZER CONDITION
Authors: QIAO SHOUHONG , QIAN GUOHUA , WANG YANMING
Published: October 2012

A group G is said to satisfy the maximal permutizer condition if the permutizer of any maximal subgroup M of G is equal to G. In this note, a characterization is given of finite groups which satisfy the maximal permutizer condition.
INTERSECTION GRAPH OF A MODULE
Authors: YARANERI ERGÜN
Published: October 2012

Let V be a left R-module where R is a (not necessarily commutative) ring with unit. The intersection graph [Formula: see text] of proper R-submodules of V is an undirected graph without loops and multiple edges defined as follows: the vertex set is the set of all proper R-submodules of V, and there is an edge between two distinct vertices U and W if and only if U ∩ W ≠ 0. We study these graphs to relate the combinatorial properties of [Formula: see text] to the algebraic properties of the R-module V. We study connectedness, domination, finiteness, coloring, and planarity for [Formula: see text]. For instance, we find the domination number of [Formula: see text]. We also find the chromatic number of [Formula: see text] in some cases. Furthermore, we study cycles in [Formula: see text], and complete subgraphs in [Formula: see text] determining the structure of V for which [Formula: see text] is planar.
OMEGA THEOREMS FOR $\frac{L'}{L}(1, \chi_D)$
Authors: MOURTADA M. , MURTY V. KUMAR
Published: October 2012

A classical result of Chowla [Improvement of a theorem of Linnik and Walfisz, Proc. London Math. Soc. (2) 50 (1949) 423–429 and The Collected Papers of Sarvadaman Chowla, Vol. 2 (Centre de Recherches Mathematiques, 1999), pp. 696–702] states that for infinitely many fundamental discriminants D we have [Formula: see text] where χD is the quadratic Dirichlet character of conductor D. In this paper, we prove an analogous result for the logarithmic derivative [Formula: see text], and investigate the growth of the logarithmic derivatives of real Dirichlet L-functions. We show that there are infinitely many fundamental discriminants D (both positive and negative) such that [Formula: see text] and infinitely many fundamental discriminants 0 < D such that [Formula: see text] In particular, we show that the Euler–Kronecker constant γK of a quadratic field K satisfies γK = Ω( log log |dK|). We get sharper results assuming the GRH. Moreover, we evaluate the moments of [Formula: see text].
EULER–HADAMARD PRODUCTS AND POWER MOMENTS OF SYMMETRIC SQUARE L-FUNCTIONS
Authors: DJANKOVIĆ GORAN
Published: October 2012

In this paper we prove asymptotic formulas for general moments of partial Euler products and the first and the second moments of partial Hadamard products related to central values of the family of L-functions associated to the symmetric square lifts of holomorphic modular forms for SL2(ℤ). Then using a hybrid Euler–Hadamard product formula for the central value, we relate these results with conjectures for general power moments of L-functions in this family and with Random Matrix Theory interpretations. This continues the work done previously by Gonek–Hughes–Keating and Bui–Keating for other families of L-functions.
A NANOSCALE POROUS SILICON MICROCAVITY BIOSENSOR FOR NOVEL LABEL-FREE TUBERCULOSIS ANTIGEN–ANTIBODY DETECTION
Authors: WU BAO , RONG GUOGUANG , ZHAO JUNWEI , ZHANG SHULIN , ZHU YONGXIN , HE BOYONG
Published: October 2012

One third of the world population is estimated to have Mycobacterium tuberculosis infection. It is urgent to develop a rapid, inexpensive and convenient diagnostic method for detection of tuberculosis. Porous silicon material has taken more and more attention in recent years for biosensing applications and some useful results have been obtained. In this paper, we report the feasibility of applying porous silicon microcavity biosensor in a novel and relatively rapid serodiagnostic approach. Nowadays, most of serodiagnostic tests are based on labeled detection. Applying label-free detection methods can help develop fast and efficient tuberculosis diagnostic tools, which can meet the current demand. In this study, we use this label-free sensing platform (i.e., porous silicon microcavity) to detect the interaction between 16 kDa antigen and anti-16 kDa antibody. Through a series of experiments, we verify the specificity and examine the sensitivity of this new diagnostic technique. The results show that it is feasible to apply porous silicon microcavity in the tests of tuberculosis.
IN SITUPREPARATION AND INHIBITORY ACTIVITY OF HYDROXYAPATITE/SILVER NANOCOMPOSITE
Authors: XIE HONG-ZHEN , WANG JIAN-DONG , LUO CHONG-XIAO , LIU JIN-KU
Published: October 2012

The hydroxyapatite (HAP) assembled microsphere chains/silver ( Ag ) nanocomposites were prepared by a facile in situ preparation method under hydrothermal condition. The crystal structure of products was characterized by X-ray diffraction (XRD) and the morphologies of products were investigated by transmission electron microscopy (TEM). The nanocomposites own large surface area and can hydrogen-bond to other substances by the hydroxyl group on the surface. The nanocomposites have good structural stability under the electrostatic effect of the silver nanoparticles and strong adsorbability of the HAP microsphere chains. The two substances combine to form special nanocomposite spheres. Specially, the HAP/ Ag nanocomposites have high inhibitory activity and can be applied in the environment and medicine fields. The nanocomposite structures can save the consumption of Ag materials.
CHAOS ANALYSIS AND CONTROL FOR A CLASS OF SIR EPIDEMIC MODEL WITH SEASONAL FLUCTUATION
Authors: ZHANG YI , ZHANG QINGLING , ZHANG FUZHEN , BAI FENGLAN
Published: October 2012

In this paper, the problems of chaos and chaos control for a class of susceptible-infected-removed (SIR) epidemic model with seasonal fluctuation are investigated. The seasonality in outbreak is natural among infectious diseases, as the common influenza, A type H1N1 influenza and so on. It is shown that there exist chaotic phenomena in the epidemic model. Furthermore, the tracking control method is used to control chaotic motions in the epidemic model. A feedback controller is designed to achieve tracking of an ideal output. Thus, the density of infected individuals can converge to zero, in other words, the disease can be disappeared. Finally, numerical simulations illustrate that the controller is effective.
The effectiveness of stackelberg strategies and tolls for network congestion games
Authors: Swamy Chaitanya
Published: October 2012

It is well known that in a network with arbitrary (convex) latency functions that are a function of edge traffic, the worst-case ratio, over all inputs, of the system delay caused due to selfish behavior versus the system delay of the optimal centralized solution may be
unbounded
even if the system consists of only two parallel links. This ratio is called the
price of anarchy
(PoA). In this article, we investigate ways by which one can reduce the performance degradation due to selfish behavior. We investigate two primary methods (a)
Stackelberg routing strategies
, where a central authority, for example, network manager, controls a fixed fraction of the flow, and can route this flow in any desired way so as to influence the flow of selfish users; and (b)
network tolls
, where tolls are imposed on the edges to modify the latencies of the edges, and thereby influence the induced Nash equilibrium. We obtain results demonstrating the effectiveness of both Stackelberg strategies and tolls in controlling the price of anarchy.

For Stackelberg strategies, we obtain the first results for nonatomic routing in graphs more general than parallel-link graphs, and strengthen existing results for parallel-link graphs. (i) In series-parallel graphs, we show that Stackelberg routing reduces the PoA to a constant (depending on the fraction of flow controlled). (ii) For general graphs, we obtain latency-class specific bounds on the PoA with Stackelberg routing, which give a continuous trade-off between the fraction of flow controlled and the price of anarchy. (iii) In parallel-link graphs, we show that for
any
given class
L
of latency functions, Stackelberg routing reduces the PoA to at most α + (1-α)ċρ(
L
), where α is the fraction of flow controlled and ρ(
L
) is the PoA of class
L
(when α = 0).

For network tolls, motivated by the known strong results for nonatomic games, we consider the more general setting of
atomic splittable
routing games. We show that tolls inducing an optimal flow always exist, even for general asymmetric games with heterogeneous users, and can be computed efficiently by solving a
convex program
. This resolves a basic open question about the effectiveness of tolls for atomic splittable games. Furthermore, we give a complete characterization of flows that can be induced via tolls.
An FPTAS for the minimum total weighted tardiness problem with a fixed number of distinct due dates
Authors: Karakostas George , Kolliopoulos Stavros G. , Wang Jing
Published: October 2012

Given a sequencing of jobs on a single machine, each one with a weight, processing time, and a due date, the tardiness of a job is the time needed for its completion beyond its due date. We present an FPTAS for the basic scheduling problem of minimizing the total weighted tardiness when the number of distinct due dates is fixed. Previously, an FPTAS was known only for the case where all jobs have a common due date.
Energy Conservation for Image Retrieval on Mobile Systems
Authors: Kumar Karthik , Nimmagadda Yamini , Lu Yung-Hsiang
Published: October 2012

Mobile systems such as PDAs and cell phones play an increasing role in handling visual contents such as images. Thousands of images can be stored in a mobile system with the advances in storage technology: this creates the need for better organization and retrieval of these images. Content Based Image Retrieval (CBIR) is a method to retrieve images based on their visual contents. In CBIR, images are compared by matching their numerical representations called features; CBIR is computation and memory intensive and consumes significant amounts of energy. This article examines energy conservation for CBIR on mobile systems. We present three improvements to save energy while performing the computation on the mobile system: selective loading, adaptive loading, and caching features in memory. Using these improvements adaptively reduces the features to be loaded into memory for each search. The reduction is achieved by estimating the difficulty of the search. If the images in the collection are dissimilar, fewer features are sufficient; less computation is performed and energy can be saved. We also consider the effect of consecutive user queries and show how features can be cached in memory to save energy. We implement a CBIR algorithm on an HP iPAQ hw6945 and show that these improvements can save energy and allow CBIR to scale up to 50,000 images on a mobile system. We further investigate if energy can be saved by migrating parts of the computation to a server, called
computation offloading
. We analyze the impact of the wireless bandwidth, server speed, number of indexed images, and the number of image queries on the energy consumption. Using our scheme, CBIR can be made energy efficient under all conditions.
Runtime energy consumption estimation for server workloads based on chaotic time-series approximation
Authors: Lewis Adam Wade , Tzeng Nian-Feng , Ghosh Soumik
Published: October 2012

This article proposes a runtime model that relates server energy consumption to its overall thermal envelope, using hardware performance counters and experimental measurements. While previous studies have attempted system-wide modeling of server power consumption through subsystem models, our approach is different in that it links system energy input to subsystem energy consumption based on a small set of tightly correlated parameters. The proposed model takes into account processor power, bus activities, and system ambient temperature for real-time prediction on the power consumption of long running jobs. Using the HyperTransport and QuickPath Link structures as case studies and through electrical measurements on example server subsystems, we develop a chaotic time-series approximation for runtime power consumption, arriving at the Chaotic Attractor Predictor (CAP). With polynomial time complexity, CAP exhibits high prediction accuracy, having the prediction errors within 1.6% (or 3.3%) for servers based on the HyperTransport bus (or the QuickPath Links), as verified by a set of common processor benchmarks. Our CAP is a superior predictive mechanism over existing linear auto-regressive methods, which require expensive and complex corrective steps to address the nonlinear and chaotic aspects of the underlying physical system.
Mixed speculative multithreaded execution models
Authors: Xekalakis Polychronis , Ioannou Nikolas , Cintra Marcelo
Published: October 2012

The current trend toward multicore architectures has placed great pressure on programmers and compilers to generate thread-parallel programs. Improved execution performance can no longer be obtained via traditional single-thread instruction level parallelism (ILP), but, instead, via multithreaded execution. One notable technique that facilitates the extraction of parallel threads from sequential applications is thread-level speculation (TLS). This technique allows programmers/compilers to generate threads without checking for inter-thread data and control dependences, which are then transparently enforced by the hardware. Most prior work on TLS has concentrated on thread selection and mechanisms to efficiently support the main TLS operations, such as squashes, data versioning, and commits.

This article seeks to enhance TLS functionality by combining it with other speculative multithreaded execution models. The main idea is that TLS already requires extensive hardware support, which when slightly augmented can accommodate other speculative multithreaded techniques. Recognizing that for different applications, or even program phases, the application bottlenecks may be different, it is reasonable to assume that the more versatile a system is, the more efficiently it will be able to execute the given program.

Toward this direction, we first show that mixed execution models that combine TLS with Helper Threads (HT), RunAhead execution (RA) and MultiPath execution (MP) perform better than any of the models alone. Based on a simple model that we propose, we show that benefits come from being able to extract additional ILP without harming the TLP extracted by TLS. We then show that by combining all the execution models in a unified one that combines all these speculative multithreaded models, ILP can be further enhanced with only minimal additional cost in hardware.
Static analysis of the worst-case memory performance for irregular codes with indirections
Authors: Andrade Diego , Fraguela Basilio B. , Doallo Ramón
Published: October 2012

Real-time systems are subject to timing constraints, whose upper bound is given by the Worst-Case Execution Time (WCET). Cache memory behavior is difficult to predict analytically and estimating a safe and precise worst-case value is even more challenging. The worst-case memory performance (WCMP) component of the WCET can only be estimated with the precise knowledge of the stream of data addresses accessed by the code, which is determined by the access patterns and the base addresses of the data structures accessed. The regularity of strided access patterns simplifies their analysis, as they are characterized by relatively few parameters, which are often available at compile time. Unfortunately codes may exhibit irregular access patterns, which are much more difficult to statically analyze. As for the base addresses of the data structures, they are not always available at compile-time for many reasons: stack variables, dynamically allocated memory, modules compiled separately, etc. This article addresses these problems by presenting a model that predicts an %safe and upper bound of the data cache performance for codes both with regular and irregular access patterns, which is valid for any possible base addresses of the data structures. The model analyzes irregular access patterns due to the presence of indirections in the code and it can provide two kinds of predictions: a safe hard boundary that is suitable for hard real-time systems and a soft boundary whose safeness is not guaranteed but which is valid most of the times. In fact, in all our experiments the number of misses was below the soft boundary predicted by the model. This turns this soft boundary prediction into a valuable tool, particularly for non and soft real-time systems, which tolerate a percentage of the runs exceeding their deadlines.
Deconstructing iterative optimization
Authors: Chen Yang , Fang Shuangde , Huang Yuanjie , Eeckhout Lieven , Fursin Grigori , Temam Olivier , Wu Chengyong
Published: October 2012

Iterative optimization is a popular compiler optimization approach that has been studied extensively over the past decade. In this article, we deconstruct iterative optimization by evaluating whether it works across datasets and by analyzing why it works.

Up to now, most iterative optimization studies are based on a premise which was never truly evaluated: that it is possible to learn the best compiler optimizations across datasets. In this article, we evaluate this question for the first time with a very large number of datasets. We therefore compose KDataSets, a dataset suite with 1000 datasets for 32 programs, which we release to the public. We characterize the diversity of KDataSets, and subsequently use it to evaluate iterative optimization. For all 32 programs, we find that there exists at least one combination of compiler optimizations that achieves at least 83% or more of the best possible speedup across
all
datasets on two widely used compilers (Intel's ICC and GNU's GCC). This optimal combination is program-specific and yields speedups up to 3.75× (averaged across datasets of a program) over the highest optimization level of the compilers (-O3 for GCC and -fast for ICC). This finding suggests that optimizing programs across datasets might be much easier than previously anticipated.

In addition, we evaluate the idea of introducing compiler choice as part of iterative optimization. We find that it can further improve the performance of iterative optimization because different programs favor different compilers. We also investigate why iterative optimization works by analyzing the optimal combinations. We find that only a handful optimizations yield most of the speedup. Finally, we show that optimizations interact in a complex and sometimes counterintuitive way through two case studies, which confirms that iterative optimization is an irreplaceable and important compiler strategy.
A transpose-free in-place SIMD optimized FFT
Authors: Geraci James R. , Sacco Sharon M.
Published: October 2012

A transpose-free in-place SIMD optimized algorithm for the computation of large FFTs is introduced and implemented on the Cell Broadband Engine. Six different FFT implementations of the algorithm using six different data movement methods are described. Their relative performance is compared for input sizes from 2
17
to 2
21
complex floating point samples. Large differences in performance are observed among even theoretically equivalent data movement patterns. All six implementations compare favorably with FFTW and other previous FFT implementations.
Competing memes propagation on networks
Authors: Wei Xuetao , Valler Nicholas , Prakash B. Aditya , Neamtiu Iulian , Faloutsos Michalis , Faloutsos Christos
Published: October 2012

If a false rumor propagates via Twitter, while the truth propagates between friends in Facebook, which one will prevail? This question captures the essence of the problem we address here. We study the intertwined propagation of two competing "memes" (or viruses, rumors, products etc.) in a composite network. A key novelty is the use of a composite network, which in its simplest model is defined as a single set of nodes with two distinct types of edges interconnecting them. Each meme spreads across the composite network in accordance to an SIS-like propagation model (a flu-like infection-recovery). To study the epidemic behavior of our system, we formulate it as a non-linear dynamic system (NLDS). We develop a metric for each meme that is based on the eigenvalue of an appropriately constructed matrix and argue that this metric plays a key role in determining the "winning" meme. First, we prove that our metric determines the tipping point at which both memes become extinct eventually. Second, we conjecture that the meme with the strongest metric will most likely prevail over the other, and we show evidence of that via simulations in both real and synthetic composite networks. Our work is among the first to study the interplay between two competing memes in composite networks.
Investigating the IPv6 teredo tunnelling capability and performance of internet clients
Authors: Zander Sebastian , Andrew Lachlan L.H. , Armitage Grenville , Huston Geoff , Michaelson George
Published: October 2012

The Teredo auto-tunnelling protocol allows IPv6 hosts behind IPv4 NATs to communicate with other IPv6 hosts. It is enabled by default on Windows Vista and Windows 7. But Windows clients are self-constrained: if their only IPv6 access is Teredo, they are unable to resolve host names to IPv6 addresses. We use web-based measurements to investigate the (latent) Teredo capability of Internet clients, and the delay introduced by Teredo. We compare this with native IPv6 and 6to4 tunnelling capability and delay. We find that only 6--7% of connections are from fully IPv6-capable clients, but an additional 15--16% of connections are from clients that would be IPv6-capable if Windows Teredo was not constrained. However, Teredo increases the median latency to fetch objects by 1--1.5 seconds compared to IPv4 or native IPv6, even with an optimally located Teredo relay. Furthermore, in many cases Teredo fails to establish a tunnel.
DXR
Authors: Zec Marko , Rizzo Luigi , Mikuc Miljenko
Published: October 2012

Can a software routing implementation compete in a field generally reserved for specialized lookup hardware? This paper presents DXR, an IPv4 lookup scheme based on transforming large routing tables into compact lookup structures which easily fit into cache hierarchies of modern CPUs. DXR supports various memory/speed tradeoffs and scales almost linearly with the number of CPU cores. The smallest configuration, D16R, distills a real-world BGP snapshot with 417,000 IPv4 prefixes and 213 distinct next hops into a structure consuming only 782 Kbytes, less than 2 bytes per prefix, and achieves 490 million lookups per second (MLps) in synthetic tests using uniformly random IPv4 keys on a commodity 8-core CPU. Some other DXR configurations exceed 700~MLps at the cost of increased memory footprint. DXR significantly outperforms a software implementation of DIR-24-8-BASIC, has better scalability, and requires less DRAM bandwidth. Our prototype works inside the FreeBSD kernel, which permits DXR to be used with standard APIs and routing daemons such as Quagga and XORP, and to be validated by comparing lookup results against the BSD radix tree.
Privacy risks in named data networking
Authors: Lauinger Tobias , Laoutaris Nikolaos , Rodriguez Pablo , Strufe Thorsten , Biersack Ernst , Kirda Engin
Published: October 2012

Named Data Networking architectures have been proposed to improve various shortcomings of the current Internet architecture. A key part of these proposals is the capability of caching arbitrary content in arbitrary network locations. While caching has the potential to improve network performance, the data stored in caches can be seen as transient traces of past communication that attackers can exploit to compromise the users' privacy. With this editorial note, we aim to raise awareness of privacy attacks as an intrinsic and relevant issue in Named Data Networking architectures. Countermeasures against privacy attacks are subject to a trade-off between performance and privacy. We discuss several approaches to countermeasures representing different incarnations of this tradeoff, along with open issues to be looked at by the research community.
Periconceptional Undernutrition in Sheep Affects Adult Phenotype Only in Males
Authors: Jaquiery Anne L. , Oliver Mark H. , Honeyfield-Ross Maggie , Harding Jane E. , Bloomfield Frank H.
Published: October 2012

Periconceptional undernutrition (PCUN) in sheep alters fetal growth and metabolism and postnatal growth regulation, but effects on adult body composition are unknown. We investigated the effects of PCUN on adult phenotype. Singleton lambs of ewes fed normally (N,n=17) or undernourished before (UN-61-0 d,n=23), before and after (UN-61-30 d,n=19), or after (UN-2-30d,n=17) mating (d0) were weighed at birth, 12 weeks, and intermittently to adulthood. At the age of 3-4 years, body composition was assessed by dual-emission X-ray absorptiometry followed bypostmortemexamination. Compared with N animals, male, but not female, offspring of all UN groups had greater % fat mass (all UN versus N:9±1versus2±1%,P<0.001) and perirenal fat (544±36versus222±44 g,P=0.002), and proportionately smaller hearts (4.5±0.1versus5.2±0.2 g·kg−1), lungs (9.1±0.2versus10.6±0.5 g·kg−1), and adrenals (0.06±0.002versus0.08±0.003 g·kg−1). UN males also had larger testes (726±21versus545±32 g,P=0.007), but UN females had smaller ovaries (2.7±0.08versus3.4±0.4 g,P=0.01). Changes were independent of birth weight or postnatal growth velocity. Brief PCUN has sex-specific effects on adult phenotype, predominantly affecting males, which may contribute to adverse metabolic outcomes.
Technical Barriers and Development of Cu Wirebonding in Nanoelectronics Device Packaging
Authors: Gan C. L. , Ng E. K. , Chan B. L. , Hashim U. , Classe F. C.
Published: October 2012

Bondpad cratering, Cu ball bond interface corrosion, IMD (intermetal dielectric) cracking, and uncontrolled post‐wirebond staging are the key technical barriers in Cu wire development. This paper discusses the UHAST (unbiased HAST) reliability performance of Cu wire used in fine‐pitch BGA package. In‐depth failure analysis has been carried out to identify the failure mechanism under various assembly conditions. Obviously green mold compound, low‐halogen substrate, optimized Cu bonding parameters, assembly staging time after wirebonding, and anneal baking after wirebonding are key success factors for Cu wire development in nanoelectronic packaging. Failure mechanisms of Cu ball bonds after UHAST test and CuAl IMC failure characteristics have been proposed and discussed in this paper.
Cutting Properties of Austenitic Stainless Steel by Using Laser Cutting Process without Assist Gas
Authors: Ozaki Hitoshi , Koike Yosuke , Kawakami Hiroshi , Suzuki Jippei
Published: October 2012

Recently, laser cutting is used in many industries. Generally, in laser cutting of metallic materials, suitable assist gas and its nozzle are needed to remove the molten metal. However, because of the gas nozzle should be set closer to the surface of a workpiece, existence of the nozzle seems to prevent laser cutting from being used flexible. Therefore, the new cutting process, Assist Gas Free laser cutting or AGF laser cutting, has been developed. In this process, the pressure at the bottom side of a workpiece is reduced by a vacuum pump, and the molten metal can be removed by the air flow caused by the pressure difference between both sides of the specimen. In this study, cutting properties of austenitic stainless steel by using AGF laser cutting with 2 kW CO2 laser were investigated. Laser power and cutting speed were varied in order to study the effect of these parameters on cutting properties. As a result, austenitic stainless steel could be cut with dross-free by AGF laser cutting. When laser power was 2.0 kW, cutting speed could be increased up to 100 mm/s, and kerf width at specimen surface was 0.28 mm.
Effect of Pioglitazone on the Fructose-Induced Abdominal Adipose Tissue Dysfunction
Authors: Alzamendi Ana , Giovambattista Andrés , García María E. , Rebolledo Oscar R. , Gagliardino Juan J. , Spinedi Eduardo
Published: October 2012

Aim. To test the potential role of PPARγin the endocrine abdominal tissue dysfunction induced by feeding normal rats with a fructose rich diet (FRD) during three weeks.Methodology. Adult normal male rats received a standard commercial diet (CD) or FRD, (10% in drinking water) without or with pioglitazone (PIO) (i.p. 0.25 mg/Kg BW/day; CD-PIO and FRD-PIO). Thereafter, we measured circulating metabolic, endocrine, and oxidative stress (OS) markers, abdominal adipose tissue (AAT) mass, leptin (LEP) and plasminogen activator inhibitor-1 (PAI-1) tissue content/expression, and leptin release by isolated adipocytes incubated with different concentrations of insulin.Results. Plasma glucose, insulin, triglyceride, TBARS, LEP, and PAI-1 levels were higher in FRD rats; PIO coadministration fully prevented all these increments. AAT adipocytes from FRD rats were larger, secreted a higher amount of LEP, and displayed decreased sensitivity to insulin stimulation; these effects were significantly ameliorated by PIO. Whereas AAT LEP and PAI-1 (mRNA) concentrations increased significantly in FRD rats, those of insulin-receptor-substrate- (IRS-) 1 and IRS-2 were reduced. PIO coadministration prevented FRD effects on LEP, PAI-1, and IRS-2 (fully) and IRS-1 (partially) mRNAs in AAT.Conclusion. PPARγwould play a relevant role in the development of the FRD-induced metabolic-endocrine dysfunction.
Eulerian Oil Spills Model Using Finite-Volume Method with Moving Boundary and Wet-Dry Fronts
Authors: Sarhadi Zadeh Ehsan , Hejazi Kourosh
Published: October 2012

The world production of crude oil is about 3 billion tons per year. The overall objective of the model in present study is supporting the decision makers in planning and conducting preventive and emergency interventions. The conservative equation for the slick dynamics was derived from layer-averaged Navier-Stokes (LNS) equations, averaged over the slick thickness. Eulerian approach is applied across the model, based on nonlinear shallow water Reynolds-averaged Navier-Stokes (RANS) equations. Depth-integrated standard k-εturbulence schemes have been included in the model. Wetting and drying fronts of intertidal zone and moving boundary are treated within the numerical model. A highly accurate algorithm based on a fourth-degree accurate shape function has been used through an alternating-direction implicit (ADI) scheme which separates the operators into locally one-dimensional (LOD) components. The solution has been achieved by the application of KPENTA algorithm for the set of the flow equations which constitutes a pentadiagonal matrix. Hydrodynamic model was validated for a channel with a sudden expansion in width. For validation of oil spill model, predicted results are compared with experimental data from a physical modeling of oil spill in a laboratory wave basin under controlled conditions.
Antioxidant, Antinociceptive, and Anti-Inflammatory Effects of Carotenoids Extracted from Dried Pepper (Capsicum annuumL.)
Authors: Hernández-Ortega Marcela , Ortiz-Moreno Alicia , Hernández-Navarro María Dolores , Chamorro-Cevallos Germán , Dorantes-Alvarez Lidia , Necoechea-Mondragón Hugo
Published: October 2012

Carotenoids extracted from dried peppers were evaluated for their antioxidant, analgesic, and anti-inflammatory activities. Peppers had a substantial carotenoid content: guajillo3406±4 μg/g, pasilla2933±1 μg/g, and ancho1437±6 μg/g of sample in dry weight basis. A complex mixture of carotenoids was discovered in each pepper extract. The TLC analysis revealed the presence of chlorophylls in the pigment extract from pasilla and ancho peppers. Guajillo pepper carotenoid extracts exhibited good antioxidant activity and had the best scavenging capacity for the DPPH+cation (24.2%). They also exhibited significant peripheral analgesic activity at 5, 20, and 80 mg/kg and induced central analgesia at 80 mg/kg. The results suggest that the carotenoids in dried guajillo peppers have significant analgesic and anti-inflammatory benefits and could be useful for pain and inflammation relief.
Mould Filling Ability Characterisation of Cast Aluminium Alloys Using Design of Experiments
Authors: Santhi Samavedam , Sakri S. B. , Hanumantha Rao Dharwada , Sundarrajan Srinivasan
Published: October 2012

Mould filling ability characteristic has been influencing the liquid metal flow, heat transfer, and solidification there by affecting the quality of aerospace castings. Mould filling is a critical parameter in the production of sound and quality castings, especially in the case of complex-shaped castings where section thickness is varying considerably. The mould filling ability of aluminium alloys LM6 and LM25 has been studied in the present investigation. Experimentation has been carried out using orthogonal array experimental layout. The process parameters studied in the present investigation are alloy composition, sand fineness, mould coating, and pouring temperature. The mould filling ability of selected aluminium alloy has been studied using pin test piece with cylindrical cores. The results from experimentation are analyzed to find the influence of the process parameters on mould filling ability. Based on the above, LM6 alloy has been found to have better mould filling ability characteristics and the analysis of variance has also revealed the same optimum factor combination.
Long-Term Costs of Ischemic Stroke and Major Bleeding Events among Medicare Patients with Nonvalvular Atrial Fibrillation
Authors: Mercaldi Catherine J. , Siu Kimberly , Sander Stephen D. , Walker David R. , Wu You , Li Qian , Wu Ning
Published: October 2012

Purpose. Acute healthcare utilization of stroke and bleeding has been previously examined among patients with nonvalvular atrial fibrillation (NVAF). The long-term cost of such outcomes over several years is not well understood.Methods. Using 1999–2009 Medicare medical and enrollment data, we identified incident NVAF patients without history of stroke or bleeding. Patients were followed from the first occurrence of ischemic stroke, major bleeding, or intracranial hemorrhage (ICH) resulting in hospitalization. Those with events were matched with 1–5 NVAF patients without events. Total incremental costs of events were calculated as the difference between costs for patients with events and matched controls for up to 3 years.Results. Among the 25,465 patients who experienced events, 94.5% were successfully matched. In the first year after event, average incremental costs were $32,900 for ischemic stroke, $23,414 for major bleeding, and $47,640 for ICH. At 3 years after these events, costs remained elevated by $3,156–$5,400 per annum.Conclusion. While the costs of stroke and bleeding among patients with NVAF are most dramatic in the first year, utilization remained elevated at 3 years. Cost consequences extend beyond the initial year after these events and should be accounted for when assessing the cost-effectiveness of treatment regimens for stroke prevention.
A Computational Modeling Approach for Investigating Soft Tissue Balancing in Bicruciate Retaining Knee Arthroplasty
Authors: Amiri Shahram , Wilson David R.
Published: October 2012

Bicruciate retaining knee arthroplasty, although has shown improved functions and patient satisfaction compared to other designs of total knee replacement, remains a technically demanding option for treating severe cases of arthritic knees. One of the main challenges in bicruciate retaining arthroplasty is proper balancing of the soft tissue during the surgery. In this study biomechanics of soft tissue balancing was investigated using a validated computational model of the knee joint with high fidelity definitions of the soft tissue structures along with a Taguchi method for design of experiments. The model was used to simulate intraoperative balancing of soft tissue structures following the combinations suggested by an orthogonal array design. The results were used to quantify the corresponding effects on the laxity of the joint under anterior-posterior, internal-external, and varus-valgus loads. These effects were ranked for each ligament bundle to identify the components of laxity which were most sensitive to the corresponding surgical modifications. The resulting map of sensitivity for all the ligament bundles determined the components of laxity most suitable for examination during intraoperative balancing of the soft tissue. Ultimately, a sequence for intraoperative soft tissue balancing was suggested for a bicruciate retaining knee arthroplasty.
Robust H2/H∞ Filter Design for a Class of Nonlinear Stochastic Systems with State‐Dependent Noise
Authors: Zhang Weihai , Chen Bor-Sen , Sheng Li , Gao Ming
Published: October 2012

This paper investigates the problem of robust filter design for a class of nonlinear stochastic systems with state‐dependent noise. The state and measurement are corrupted by stochastic uncertain exogenous disturbance and the dynamic system is modeled by Itô‐type stochastic differential equations. For this class of nonlinear stochastic systems, the robust H∞ filter can be designed by solving linear matrix inequalities (LMIs). Moreover, a mixed H2/H∞ filtering problem is also solved by minimizing the total estimation error energy when the worst‐case disturbance is considered in the design procedure. A numerical example is provided to illustrate the effectiveness of the proposed method.
Estimation for Stochastic Nonlinear Systems with Randomly Distributed Time‐Varying Delays and Missing Measurements
Authors: Che Yan , Shu Huisheng , Kan Xiu
Published: October 2012

The estimation problem is investigated for a class of stochastic nonlinear systems with distributed time‐varying delays and missing measurements. The considered distributed time‐varying delays, stochastic nonlinearities, and missing measurements are modeled in random ways governed by Bernoulli stochastic variables. The discussed nonlinearities are expressed by the statistical means. By using the linear matrix inequality method, a sufficient condition is established to guarantee the mean‐square stability of the estimation error, and then the estimator parameters are characterized by the solution to a set of LMIs. Finally, a simulation example is exploited to show the effectiveness of the proposed design procedures.
Persistent Dystrophin Protein Restoration 90 Days after a Course of Intraperitoneally Administered Naked 2′OMePS AON and ZM2 NP-AON Complexes in mdx Mice
Authors: Bassi Elena , Falzarano Sofia , Fabris Marina , Gualandi Francesca , Merlini Luciano , Vattemi Gaetano , Perrone Daniela , Marchesi Elena , Sabatelli Patrizia , Sparnacci Katia , Laus Michele , Bonaldo Paolo , Rimessi Paola , Braghetta Paola , Ferlini Alessandra
Published: October 2012

In Duchenne muscular dystrophy, the exon-skipping approach has obtained proof of concept in animal models, myogenic cell cultures, and following local and systemic administration in Duchenne patients. Indeed, we have previously demonstrated that low doses (7.5 mg/Kg/week) of2′-O-methyl-phosphorothioate antisense oligoribonucleotides (AONs) adsorbed onto ZM2 nanoparticles provoke widespread dystrophin restoration 7 days after intraperitoneal treatment in mdx mice. In this study, we went on to test whether this dystrophin restoration was still measurable 90 days from the end of the same treatment. Interestingly, we found that both western blot and immunohistochemical analysis (up to 7% positive fibres) were still able to detect dystrophin protein in the skeletal muscles of ZM2-AON-treated mice at this time, and the level of exon-23 skipping could still be assessed by RT real-time PCR (up to 10% of skipping percentage). In contrast, the protein was undetectable by western blot analysis in the skeletal muscles of mdx mice treated with an identical dose of naked AON, and the percentage of dystrophin-positive fibres and exon-23 skipping were reminiscent of those of untreated mdx mice. Our data therefore demonstrate the long-term residual efficacy of this systemic low-dose treatment and confirm the protective effect nanoparticles exert on AON molecules.
Characterization and Hydrogen Storage of Surface‐Modified Multiwalled Carbon Nanotubes for Fuel Cell Application
Authors: Lin Kuen-Song , Mai Yao-Jen , Li Shin-Rung , Shu Chia-Wei , Wang Chieh-Hung
Published: October 2012

The synthesis, identification, and H2 storage of multiwalled carbon nanotubes (MWCNTs) have been investigated in the present work. MWCNTs were produced from the catalytic‐assembly solvent (benzene)‐thermal (solvothermal) route. Reduction of C6Cl6 with metallic potassium was carried out in the presence of Co/Ni catalyst precursors at 503–623 K for 12 h. XRD patterns indicated that the abstraction of Cl from hexachlorobenzene and the formation of KCl precipitates were involved in the early stage of the synthesis process of MWCNTs. This result offers further explanation for the formation of MWCNT structure and yield using the solvothermal route depending on the Co/Ni catalyst precursors. The diameter of MWCNTs ranged between 30 and 100 nm and the H2 storage capacity of MWCNTs improved when 2.7–3.8 wt% Pd or NaAlH4 were doped. The XANES/EXAFS spectra revealed that the Co/Ni catalyst precursors of the MWCNT synthesis were in metallic form and Pd atoms possessed a Pd–Pd bond distance of 2.78 Å with a coordination number of 9.08. Ti‐NaAlH4 or Pd nanoparticles were dispersed on MWCNTs and facilitated to improve the H2 storage capacity significantly with the surface modification process.