bluuebunny/crossref_metadata_2025 huggingface dataset:
Positive and nodal solutions for an elliptic equation with critical growth
Authors: Furtado Marcelo F. , Souza Bruno N.
Published: February 2015

We consider the problem [Formula: see text] where [Formula: see text] is a bounded smooth domain, [Formula: see text], [Formula: see text], [Formula: see text]. Under some suitable conditions on the continuous potential [Formula: see text] and on the parameter [Formula: see text], we obtain one nodal solution for [Formula: see text] and one positive solution for [Formula: see text].
Plugging Versus Logging
Authors: Chang Li-Pin , Su Yo-Chuan , Wu I-Chen
Published: February 2015

A promising technique to improve the write performance of solid-state disks (SSDs) is to use a disk write buffer. The goals of a write buffer is not only to reduce the write traffic to the flash chips but also to convert host write patterns into long and sequential write bursts. This study proposes a new buffer design consisting of a replacement policy and a write-back policy. The buffer monitors how the host workload stresses the flash translation layer upon garbage collection. This is used to dynamically adjust its replacement and write-back strategies for a good balance between write sequentiality and write randomness. When the garbage collection overhead is low, the write buffer favors high write sequentiality over low write randomness. When the flash translation layer observes a high overhead of garbage collection, the write buffer favors low write randomness over high write sequentiality. The proposed buffer design outperformed existing approaches by up to 20% under various workloads and flash translation algorithms, as will be shown in experiment results.
Using a Flexible Fault-Tolerant Cache to Improve Reliability for Ultra Low Voltage Operation
Authors: Banaiyanmofrad Abbas , Homayoun Houman , Dutt Nikil
Published: February 2015

Caches are known to consume a large part of total microprocessor power. Traditionally, voltage scaling has been used to reduce both dynamic and leakage power in caches. However, aggressive voltage reduction causes process-variation--induced failures in cache SRAM arrays, which compromise cache reliability. In this article, we propose FFT-Cache, a flexible fault-tolerant cache that uses a flexible defect map to configure its architecture to achieve significant reduction in energy consumption through aggressive voltage scaling while maintaining high error reliability. FFT-Cache uses a portion of faulty cache blocks as redundancy—using block-level or line-level replication within or between sets—to tolerate other faulty caches lines and blocks. Our configuration algorithm categorizes the cache lines based on degree of conflict between their blocks to reduce the granularity of redundancy replacement. FFT-Cache thereby sacrifices a minimal number of cache lines to avoid impacting performance while tolerating the maximum amount of defects. Our experimental results on a processor executing SPEC2K benchmarks demonstrate that the operational voltage of both L1/L2 caches can be reduced down to 375 mV, which achieves up to 80% reduction in the dynamic power and up to 48% reduction in the leakage power. This comes with only a small performance loss (<%5) and 13% area overhead.
A Hardware-Efficient Architecture for Accurate Real-Time Disparity Map Estimation
Authors: Ttofis Christos , Kyrkou Christos , Theocharides Theocharis
Published: February 2015

Emerging embedded vision systems utilize disparity estimation as a means to perceive depth information to intelligently interact with their host environment and take appropriate actions. Such systems demand high processing performance and accurate depth perception while requiring low energy consumption, especially when dealing with mobile and embedded applications, such as robotics, navigation, and security. The majority of real-time dedicated hardware implementations of disparity estimation systems have adopted local algorithms relying on simple cost aggregation strategies with fixed and rectangular correlation windows. However, such algorithms generally suffer from significant ambiguity along depth borders and areas with low texture. To this end, this article presents the hardware architecture of a disparity estimation system that enables good performance in both accuracy and speed. The architecture implements an adaptive support weight stereo correspondence algorithm that integrates image segmentation information in an attempt to increase the robustness of the matching process. The article also presents hardware-oriented algorithmic modifications/optimization techniques that make the algorithm hardware-friendly and suitable for efficient dedicated hardware implementation. A comparison to the literature asserts that an FPGA implementation of the proposed architecture is among the fastest implementations in terms of million disparity estimations per second (MDE/s), and with an overall accuracy of 90.21%, it presents an effective processing speed/disparity map accuracy trade-off.
Factored Planning
Authors: Jezequel Loïg , Fabre Eric , Khomenko Victor
Published: February 2015

Factored planning mitigates the state explosion problem by avoiding the construction of the state space of the whole system and instead working with the system's components. Traditionally, finite automata have been used to represent the components, with the overall system being represented as their product. In this article, we change the representation of components to safe Petri nets. This allows one to use cheap structural operations like transition contractions to reduce the size of the Petri net before its state space is generated, which often leads to substantial savings compared with automata. The proposed approach has been implemented and proved efficient on several factored planning benchmarks. This article is an extended version of our ACSD 2013 paper [Jezequel et al. 2013], with the addition of the proofs and the experimental results of Sections 6 and 7.
Computing Cumulative Rewards Using Fast Adaptive Uniformization
Authors: Dannenberg Frits , Hahn Ernst Moritz , Kwiatkowska Marta
Published: February 2015

The computation of transient probabilities for continuous-time Markov chains often employs uniformization, also known as the Jensen method. The fast adaptive uniformization method introduced by Mateescu et al. approximates the probability by neglecting insignificant states and has proven to be effective for quantitative analysis of stochastic models arising in chemical and biological applications. However, this method has only been formulated for the analysis of properties at a given point of time
t
. In this article, we extend fast adaptive uniformization to handle expected reward properties that reason about the model behavior until time
t
, for example, the expected number of chemical reactions that have occurred until
t
. To show the feasibility of the approach, we integrate the method into the probabilistic model checker PRISM and apply it to a range of biological models. The performance of the method is enhanced by the use of interval splitting. We compare our implementation to standard uniformization implemented in PRISM and to fast adaptive uniformization without support for cumulative rewards implemented in MARCIE, demonstrating superior performance.
Simulating Organogenesis
Authors: Schwaninger Clemens Arthur , Menshykau Denis , Iber Dagmar
Published: February 2015

Recent advances in imaging technology now provide us with 3D images of developing organs. These can be used to extract 3D geometries for simulations of organ development. To solve models on growing domains, the displacement fields between consecutive image frames need to be determined. Here we develop and evaluate different landmark-free algorithms for the determination of such displacement fields from image data. In particular, we examine minimal distance, normal distance, diffusion-based, and uniform mapping algorithms and test these algorithms with both synthetic and real data in 2D and 3D. We conclude that in most cases, the normal distance algorithm is the method of choice and wherever it fails, diffusion-based mapping provides a good alternative.
Secure the Cloud
Authors: Roy Arpan , Sarkar Santonu , Ganesan Rajeshwari , Goel Geetika
Published: February 2015

In response to the revival of virtualized technology by Rosenblum and Garfinkel [2005], NIST defined cloud computing, a new paradigm in service computing infrastructures. In cloud environments, the basic security mechanism is ingrained in virtualization—that is, the execution of instructions at different privilege levels. Despite its obvious benefits, the caveat is that a crashed virtual machine (VM) is much harder to recover than a crashed workstation. When crashed, a VM is nothing but a giant corrupt binary file and quite unrecoverable by standard disk-based forensics. Therefore, VM crashes should be avoided at all costs. Security is one of the major contributors to such VM crashes. This includes compromising the hypervisor, cloud storage, images of VMs used infrequently, and remote cloud client used by the customer as well as threat from malicious insiders. Although using secure infrastructures such as private clouds alleviate several of these security problems, most cloud users end up using cheaper options such as third-party infrastructures (i.e., private clouds), thus a thorough discussion of all known security issues is pertinent. Hence, in this article, we discuss ongoing research in cloud security in order of the attack scenarios exploited most often in the cloud environment. We explore attack scenarios that call for securing the hypervisor, exploiting co-residency of VMs, VM image management, mitigating insider threats, securing storage in clouds, abusing lightweight software-as-a-service clients, and protecting data propagation in clouds. Wearing a practitioner's glasses, we explore the relevance of each attack scenario to a service company like Infosys. At the same time, we draw parallels between cloud security research and implementation of security solutions in the form of enterprise security suites for the cloud. We discuss the state of practice in the form of enterprise security suites that include cryptographic solutions, access control policies in the cloud, new techniques for attack detection, and security quality assurance in clouds.
An Age-Old Problem
Authors: Vines John , Pritchard Gary , Wright Peter , Olivier Patrick , Brittain Katie
Published: February 2015

Ageing has become a significant area of interest in Human-Computer Interaction (HCI) in recent years. In this article we provide a critical analysis of 30 years of ageing research published across the ACM Special Interest Group on Computer-Human Interaction (SIGCHI) community. Discourse analysis of the content of 644 archival papers highlights how ageing is typically framed as a “problem” that can be managed by technology. We highlight how ageing is typically defined through an emphasis on the economic and societal impact of health and care needs of older people, concerns around socialisation as people age, and declines in abilities and associated reductions in performance when using technology. We draw from research within the fields of social and critical gerontology to highlight how these discourses in SIGCHI literature represent common stereotypes around old age that have also prevailed in the wider literature in gerontology. We conclude by proposing strategies for future research at the intersection of ageing and HCI.
The Effect of Wrinkles, Presentation Mode, and Intensity on the Perception of Facial Actions and Full-Face Expressions of Laughter
Authors: Niewiadomski Radoslaw , Pelachaud Catherine
Published: February 2015

This article focuses on the identification and perception of facial action units displayed alone as well as the meaning decoding and perception of full-face synthesized expressions of laughter. We argue that the adequate representation of single action units is important in the decoding and perception of full-face expressions. In particular, we focus on three factors that may influence the identification and perception of single actions and full-face expressions: their presentation mode (static vs. dynamic), their intensity, and the presence of wrinkles.

For the purpose of this study, we used a hybrid approach for animation synthesis that combines data-driven and procedural animations with synthesized wrinkles generated using a bump mapping method. Using such animation technique, we created animations of single action units and full-face movements of two virtual characters. Next, we conducted two studies to evaluate the role of presentation mode, intensity, and wrinkles in single actions and full-face context-free expressions. Our evaluation results show that intensity and presentation mode influence (1) the identification of single action units and (2) the perceived quality of the animation. At the same time, wrinkles (3) are useful in the identification of a single action unit and (4) influence the perceived meaning attached to the animation of full-face expressions. Thus, all factors are important for successful communication of expressions displayed by virtual characters.
Depth Artifacts Caused by Spatial Interlacing in Stereoscopic 3D Displays
Authors: Hakala Jussi H. , Oittinen Pirkko , Häkkinen Jukka P.
Published: February 2015

Most spatially interlacing stereoscopic 3D displays display odd and even rows of an image to either the left or the right eye of the viewer. The visual system then fuses the interlaced image into a single percept. This row-based interlacing creates a small vertical disparity between the images; however, interlacing may also induce horizontal disparities, thus generating depth artifacts. Whether people perceive the depth artifacts and, if so, what is the magnitude of the artifacts are unknown. In this study, we hypothesized and tested if people perceive interlaced edges on different depth levels. We tested oblique edge orientations ranging from 2 degrees to 32 degrees and pixel sizes ranging from 16 to 79 arcsec of visual angle in a depth probe experiment. Five participants viewed the visual stimuli through a stereoscope under three viewing conditions: noninterlaced, interlaced, and row averaged (i.e., where even and odd rows are averaged). Our results indicated that people perceive depth artifacts when viewing interlaced stereoscopic images and that these depth artifacts increase with pixel size and decrease with edge orientation angle. A pixel size of 32 arcsec of visual angle still evoked depth percepts, whereas 16 arcsec did not. Row-averaging images effectively eliminated these depth artifacts. These findings have implications for display design, content production, image quality studies, and stereoscopic games and software.
Web Query Reformulation via Joint Modeling of Latent Topic Dependency and Term Context
Authors: Bing Lidong , Lam Wai , Wong Tak-Lam , Jameel Shoaib
Published: February 2015

An important way to improve users’ satisfaction in Web search is to assist them by issuing more effective queries. One such approach is query reformulation, which generates new queries according to the current query issued by users. A common procedure for conducting reformulation is to generate some candidate queries first, then a scoring method is employed to assess these candidates. Currently, most of the existing methods are context based. They rely heavily on the context relation of terms in the history queries and cannot detect and maintain the semantic consistency of queries. In this article, we propose a graphical model to score queries. The proposed model exploits a latent topic space, which is automatically derived from the query log, to detect semantic dependency of terms in a query and dependency among topics. Meanwhile, the graphical model also captures the term context in the history query by skip-bigram and n-gram language models. In addition, our model can be easily extended to consider users’ history search interests when we conduct query reformulation for different users. In the task of candidate query generation, we investigate a social tagging data resource—Delicious bookmark—to generate addition and substitution patterns that are employed as supplements to the patterns generated from query log data.
Who, Where, When, and What
Authors: Yuan Quan , Cong Gao , Zhao Kaiqi , Ma Zongyang , Sun Aixin
Published: February 2015

Micro-blogging services and location-based social networks, such as Twitter, Weibo, and Foursquare, enable users to post short messages with timestamps and geographical annotations. The rich spatial-temporal-semantic information of individuals embedded in these geo-annotated short messages provides exciting opportunity to develop many context-aware applications in ubiquitous computing environments. Example applications include contextual recommendation and contextual search. To obtain accurate recommendations and most relevant search results, it is important to capture users’ contextual information (e.g., time and location) and to understand users’ topical interests and intentions. While time and location can be readily captured by smartphones, understanding user’s interests and intentions calls for effective methods in modeling user mobility behavior. Here, user mobility refers to
who visits which place at what time for what activity
. That is, user mobility behavior modeling must consider user (Who), spatial (Where), temporal (When), and activity (What) aspects. Unfortunately, no previous studies on user mobility behavior modeling have considered all of the four aspects jointly, which have complex interdependencies. In our preliminary study, we propose the first solution named W
4
(short for Who, Where, When, and What) to discover user mobility behavior from the four aspects. In this article, we further enhance W
4
and propose a nonparametric Bayesian model named EW
4
(short for Enhanced W
4
). EW
4
requires no parameter tuning and achieves better results over W
4
in our experiments. Given some of the four aspects of a user (e.g., time), our model is able to infer information of the other aspects (e.g., location and topical words). Thus, our model has a variety of context-aware applications, particularly in contextual search and recommendation. Experimental results on two real-world datasets show that the proposed model is effective in discovering users’ spatial-temporal topics. The model also significantly outperforms state-of-the-art baselines for various tasks including location prediction for tweets and requirement-aware location recommendation.
Unsupervised Visual and Textual Information Fusion in CBMIR Using Graph-Based Methods
Authors: Ah-Pine Julien , Csurka Gabriela , Clinchant Stéphane
Published: February 2015

Multimedia collections are more than ever growing in size and diversity. Effective multimedia retrieval systems are thus critical to access these datasets from the end-user perspective and in a scalable way. We are interested in repositories of image/text multimedia objects and we study multimodal information fusion techniques in the context of content-based multimedia information retrieval. We focus on graph-based methods, which have proven to provide state-of-the-art performances. We particularly examine two such methods: cross-media similarities and random-walk-based scores. From a theoretical viewpoint, we propose a unifying graph-based framework, which encompasses the two aforementioned approaches. Our proposal allows us to highlight the core features one should consider when using a graph-based technique for the combination of visual and textual information. We compare cross-media and random-walk-based results using three different real-world datasets. From a practical standpoint, our extended empirical analyses allow us to provide insights and guidelines about the use of graph-based methods for multimodal information fusion in content-based multimedia information retrieval.
Sensor Placement and Measurement of Wind for Water Quality Studies in Urban Reservoirs
Authors: Du Wan , Xing Zikun , Li Mo , He Bingsheng , Chua Lloyd Hock Chye , Miao Haiyan
Published: February 2015

We study the water quality in an urban district, where the surface wind distribution is an essential input but undergoes high spatial and temporal variations due to the impact of surrounding buildings. In this work, we develop an optimal sensor placement scheme to measure the wind distribution over a large urban reservoir using a limited number of wind sensors. Unlike existing solutions that assume Gaussian process of target phenomena, this study measures the wind that inherently exhibits strong non-Gaussian yearly distribution. By leveraging the local monsoon characteristics of wind, we segment a year into different monsoon seasons that follow a unique distribution respectively. We also use computational fluid dynamics to learn the spatial correlation of wind. The output of sensor placement is a set of the most informative locations to deploy the wind sensors, based on the readings of which we can accurately predict the wind over the entire reservoir in real time. Ten wind sensors are deployed. The in-field measurement results of more than 3 months suggest that the proposed sensor placement and spatial prediction scheme provides accurate wind measurement that outperforms the state-of-the-art Gaussian model based on interpolation-based approaches.
Staying Alive
Authors: Bui Nicola , Rossi Michele
Published: February 2015

Self-sustainability is a crucial step for modern sensor networks. Here, we offer an original and comprehensive framework for autonomous sensor networks powered by renewable energy sources. We decompose our design into two nested optimization steps: the inner step characterizes the optimal network operating point subject to an average energy consumption constraint, while the outer step provides online energy management policies that make the system energetically self-sufficient in the presence of unpredictable and intermittent energy sources. Our framework sheds new light into the design of pragmatic schemes for the control of energy-harvesting sensor networks and permits to gauge the impact of key sensor network parameters, such as the battery capacity, the harvester size, the information transmission rate, and the radio duty cycle. We analyze the robustness of the obtained energy management policies in the cases where the nodes have differing energy inflow statistics and where topology changes may occur, devising effective heuristics. Our energy management policies are finally evaluated considering real solar radiation traces, validating them against state-of-the-art solutions, and describing the impact of relevant design choices in terms of achievable network throughput and battery-level dynamics.
Foundations of Crowd Data Sourcing
Authors: Amsterdamer Yael , Milo Tova
Published: February 2015

Crowdsourcing techniques are very powerful when harnessed for the purpose of collecting and managing data. In order to provide sound scientific foundations for crowdsourcing and support the development of efficient crowdsourcing processes, adequate formal models must be defined. In particular, the models must formalize unique characteristics of crowd-based settings, such as the knowledge of the crowd and crowd-provided data; the interaction with crowd members; the inherent inaccuracies and disagreements in crowd answers; and evaluation metrics that capture the cost and effort of the crowd. In this paper, we review the foundational challenges in modeling crowd-based data sourcing, for its two main tasks, namely, harvesting data and processing it with the help of the crowd. For each of the two task types, we dive into the details of one foundational line of work, analyzing its model and reviewing the theoretical results established using this model, such as complexity bounds and efficient algorithms. We also overview a broader spectrum of work on crowd data sourcing, and highlight directions for further research.
Kian-Lee Tan Speaks Out on How to Build a Strong DB Group without Pushing Students Hard
Authors: Winslett Marianne , Braganholo Vanessa
Published: February 2015

Welcome to ACM SIGMOD Record's series of interviews with distinguished members of the database community. I'm Marianne Winslett, and today1 we are at the Advanced Digital Sciences Center in Singapore. I have here with me Kian-Lee Tan, who's a Provost's Chair Professor of Computer Science at the National University of Singapore, where he's also the Vice Dean for Research in the School of Computing. Kian-Lee received the President's Science Award in 2011. He has served as co-editor in chief of the VLDB Journal and editor for IEEE Transactions on Knowledge and Data Engineering, and a PC chair for VLDB and ICDE. His PhD is from the National University of Singapor.
Sudipto Das Speaks Out on Scalability and Elasticity of Database Systems
Authors: Winslett Marianne , Braganholo Vanessa
Published: February 2015

Welcome to ACM SIGMOD Record's Series of Interviews with distinguished members of the database community. I'm Marianne Winslett and today we're in Snowbird, Utah, site of the 2014 SIGMOD and PODS conference. I have here with me Sudipto Das, who is a researcher at Microsoft and the recipient of the 2013 SIGMOD Jim Gray Doctoral Dissertation Award, which is for his dissertation entitled 'Scalable and Elastic Transactional Data Stores for Cloud Computing Platforms'. Sudipto's PhD is from the University of California Santa Barbara where he worked with Divy Agrawal and Amr El Abbadi.
Preconception diet or exercise intervention in obese fathers normalizes sperm microRNA profile and metabolic syndrome in female offspring
Authors: McPherson Nicole O. , Owens Julie A. , Fullston Tod , Lane Michelle
Published: February 2015

Obesity and type 2 diabetes are increasingly prevalent across all demographics. Paternal obesity in humans and rodents can program obesity and impair insulin sensitivity in female offspring. It remains to be determined whether these perturbed offspring phenotypes can be improved through targeted lifestyle interventions in the obese father. Using a mouse model, we demonstrate that diet or exercise interventions for 8 wk (2 rounds of spermatogenesis) in obese founder males restores insulin sensitivity and normalized adiposity in female offspring. Founder diet and/or exercise also normalizes abundance of X-linked sperm microRNAs that target genes regulating cell cycle and apoptosis, pathways central to oocyte and early embryogenesis. Additionally, obesity-associated comorbidities, including inflammation, glucose intolerance, stress, and hypercholesterolemia, were good predictors for sperm microRNA abundance and offspring phenotypes. Interventions aimed at improving paternal metabolic health during specific windows prior to conception can partially normalize aberrant epigenetic signals in sperm and improve the metabolic health of female offspring.
Sympathetic reactivity in young women with a family history of hypertension
Authors: Greaney Jody L. , Matthews Evan L. , Wenner Megan M.
Published: February 2015

Young adults with a family history of hypertension (+FH) have increased risk of developing hypertension. Furthermore, the blood pressure (BP) response to sympathoexcitatory stimuli in young adults can predict the future development of hypertension. Therefore, we hypothesized young women with a +FH would have exaggerated cardiovascular and sympathetic reactivity compared with young women without a family history of hypertension (−FH). Beat-by-beat mean arterial pressure (MAP) and muscle sympathetic nerve activity (MSNA) were measured in 14 women +FH (22 ± 1 yr, 21 ± 1 kg/m2, MAP 80 ± 2 mmHg) and 15 women −FH (22 ± 1 yr, 22 ± 1 kg/m2, MAP 78 ± 2 mmHg) during acute sympathoexcitatory maneuvers: cold pressor test, 2 min of isometric handgrip (HG) exercise at 30% of maximal voluntary contraction, and 3 min of postexercise ischemia (PEI; isolated activation of the skeletal muscle metaboreflex). During cold pressor test, the increase in BP was greater in women +FH (ΔMAP: +FH 16 ± 2 vs. −FH 11 ± 1 mmHg, P < 0.05), which was accompanied by an exaggerated increase in MSNA (ΔMSNA: +FH 17 ± 2 vs. −FH 8 ± 2 burst/min, P < 0.05). The increase in BP was greater in +FH during the last minute of HG (ΔMAP: +FH 23 ± 3 vs. −FH 12 ± 1 mmHg, P < 0.05) and during PEI (ΔMAP: +FH 17 ± 3 vs. −FH 9 ± 2 mmHg, P < 0.05). Similarly, the increase in MSNA was greater in +FH during both HG (ΔMSNA: +FH 12 ± 2 vs. −FH 6 ± 2 burst/min, P < 0.05) and PEI (ΔMSNA: +FH 16 ± 2 vs. −FH 4 ± 2 burst/min, P < 0.05). These data demonstrate that +FH women have greater BP and sympathetic reactivity compared with −FH women.
Changes in whole tissue heme concentration dissociates muscle deoxygenation from muscle oxygen extraction during passive head-up tilt
Authors: Adami Alessandra , Koga Shunsaku , Kondo Narihiko , Cannon Daniel T. , Kowalchuk John M. , Amano Tatsuro , Rossiter Harry B.
Published: February 2015

Skeletal muscle deoxygenated hemoglobin and myoglobin concentration ([HHb]), assessed by near-infrared spectroscopy (NIRS), is commonly used as a surrogate of regional O2 extraction (reflecting the O2 delivery-to-consumption ratio, Q̇/V̇o2). However, [HHb] change (Δ[HHb]) is also influenced by capillary-venous heme concentration, and/or small blood vessel volume (reflected in total heme; [THb]). We tested the hypotheses that Δ[HHb] is associated with O2 extraction, and insensitive to [THb], over a wide range of Q̇/V̇o2 elicited by passive head-up tilt (HUT; 10-min, 15° increments, between −10° and 75°). Steady-state common femoral artery blood flow (FBF) was measured by echo-Doppler, and time-resolved NIRS measured [HHb] and [THb] of vastus lateralis (VL) and gastrocnemius (GS) in 13 men. EMG confirmed muscles were inactive. During HUT in VL [HHb] increased linearly (57 ± 10 to 101 ± 16 μM; P < 0.05 above 15°) and was associated ( r2 ∼ 0.80) with the reduction in FBF (618 ± 75 ml/min at 0° to 268 ± 52 ml/min at 75°; P < 0.05 above 30°) and the increase in [THb] (228 ± 30 vs. 252 ± 32 μM; P < 0.05 above 15°). GS response was qualitatively similar to VL. However, there was wide variation within and among individuals, such that the overall limits of agreement between Δ[HHb] and ΔFBF ranged from −35 to +19% across both muscles. Neither knowledge of tissue O2 saturation nor vascular compliance could appropriately account for the Δ[HHb]-ΔFBF dissociation. Thus, under passive tilt, [HHb] is influenced by Q̇/V̇o2, as well as microvascular hematocrit and/or tissue blood vessel volume, complicating its use as a noninvasive surrogate for muscle microvascular O2 extraction.
Echinacoside Protects against 6-Hydroxydopamine-Induced Mitochondrial Dysfunction and Inflammatory Responses in PC12 Cells via Reducing ROS Production
Authors: Wang Yue-Hua , Xuan Zhao-Hong , Tian Shuo , Du Guan-Hua
Published: February 2015

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by progressive loss of dopaminergic (DA) neurons at the substantia nigra. Mitochondrial dysfunction and inflammatory responses are involved in the mechanism of cell damage in PD. 6-Hydroxydopamine (6-OHDA), a dopamine analog, specifically damages dopaminergic neurons. Echinacoside (ECH) is a phenylethanoid glycoside isolated from the stems ofCistanche salsa, showing a variety of neuroprotective effects in previous studies. The present study was to investigate its effect against 6-OHDA-induced neurotoxicity and possible mechanisms in PC12 cells. The results showed that 6-OHDA reduced cell viability, decreased oxidation-reduction activity, decreased mitochondrial membrane potential, and induced mitochondria-mediated apoptosis compared with untreated PC12 cells. However, echinacoside treatment significantly attenuated these changes induced by 6-OHDA. In addition, echinacoside also could significantly alleviate the inflammatory responses induced by 6-OHDA. Further research showed that echinacoside could reduce 6-OHDA-induced ROS production in PC12 cells. These results suggest that the underlying mechanism of echinacoside against 6-OHDA-induced neurotoxicity may be involve in attenuating mitochondrial dysfunction and inflammatory responses by reducing ROS production.
Presence of Fatty Liver and the Relationship between Alcohol Consumption and Markers of Inflammation
Authors: Kächele Martin , Wolff Stefan , Kratzer Wolfgang , Haenle Mark , Homann Jörg , Trischler Gerlinde , Koenig Wolfgang , Imhof Armin
Published: February 2015

Background and Aims. Local and systemic inflammation represent a major feature of atherosclerotic cardiovascular disease (CVD) and are also linked to nonalcoholic fatty liver disease (NAFLD). Studies indicate that NAFLD might be a risk factor for CVD whereas low‐to‐moderate alcohol consumption is associated with lower cardiovascular morbidity and mortality compared to abstainers and heavy drinkers. We hypothesize that FLD interacts with the effect of alcohol intake on markers of inflammation, and thus potentially on cardiovascular risk. Methods and Results. We evaluated alcohol consumption, markers of inflammation and sonographic criteria of FLD in 515 subjects, representing a subsample of a cross‐sectional population based study (Echinococcus multilocularis and Internal Diseases in Leutkirch (EMIL) Study).
Presence of FLD was markedly reduced in subjects drinking 0–20 g alcohol/d (19%), compared to nondrinkers (35%) and heavy drinkers (34–44.9%). Serum concentrations of inflammatory markers were substantially higher in subjects with FLD. However, presence of FLD showed no effect on the association between alcohol consumption and inflammatory biomarkers. Conclusions. Based on data from a population‐based sample, there is no evidence for a link between FLD, alcohol consumption, and inflammatory cardiovascular risk markers. However, larger prospective studies are needed to confirm this.
A Novel SHMPWM Technique for Sensorless Control in High-Power PMSM
Authors: Yu Yanjun , Gao Lixiao , Liu Yue , Chai Feng , Cheng Shukang
Published: February 2015

In view of the low switching frequency restriction of high-power permanent magnet synchronous motor (PMSM) drive system and longing for sensorless control in hostile conditions, a novel PWM control scheme, born out of selective harmonic mitigation pulse width modulation (SHMPWM) technique, was proposed for sensorless control of high-power PMSM. A new enhanced constraint was placed on the traditional SHMPWM nonlinear transcendental equation to selectively generate constant amount of a certain3k+1order harmonic signals while guaranteed that the undesired harmonic signals can be suppressed. At the same time, the3k+1order harmonic signals were extracted by band-pass filter, which had the constant amplitude and phase angle difference of 120°, equivalent to inject rotating voltage vector in the natural coordinate system of motor, and the rotor position can be estimated using the3k+1order harmonic signals. The nonlinear transcendental equation of the novel modulation technique had been designed, and its numerical method had been analyzed. The rotor position observer had been designed according to the3k+1order harmonic signals. Simulation results verify that the harmonic suppression of the system was implemented, and the sensorless control was efficient by the novel SHMPWM technique.
A Novel Dissipativity-Based Control for Inexact Nonlinearity Cancellation Problems
Authors: Innocenti Giacomo , Paoletti Paolo
Published: February 2015

When dealing with linear systems feedback interconnected with memoryless nonlinearities, a natural control strategy is making the overall dynamics linear at first and then designing a linear controller for the remaining linear dynamics. By canceling the original nonlinearity via a first feedback loop, global linearization can be achieved. However, when the controller is not capable of exactly canceling the nonlinearity, such control strategy may provide unsatisfactory performance or even induce instability. Here, the interplay between accuracy of nonlinearity approximation, quality of state estimation, and robustness of linear controller is investigated and explicit conditions for stability are derived. An alternative controller design based on such conditions is proposed and its effectiveness is compared with standard methods on a benchmark system.
A Case of Recalcitrant Plantar Warts Associated with Statin Use
Authors: Wernham Aaron G. , Velangi Shireen S.
Published: February 2015

Background. Plantar warts are a common presenting skin complaint caused by the human papillomavirus. 1st line therapies include cryotherapy and topical salicylic acid. Where there is resistance to these treatments, consideration is made for 2nd line therapies, including intralesional bleomycin, imiquimod, 5-fluorouracil, and photodynamic therapy. We present a case of bilateral persistent plantar warts, resistant to treatment with repeated cryotherapy and topical salicylic acid over a 6-year period. Following a patient initiated decision to discontinue their statin medication, we observed rapid clearance of plantar warts without change to standard therapy or their environment. This case correlates with emerging literature demonstrating a link between statin medication and proliferation of HPV through increased levels of FOXP3+ regulatory T cells.
An Open Slot Antenna with Bandwidth Extension for WLAN/UWB Applications
Authors: Deng Jing-Ya , Fan Tian-Qi , Zhang Yan , Wen Xiang , Liu Guo-Qiang , Guo Li-Xin
Published: February 2015

An open slot antenna with extended bandwidth for WLAN and UWB applications is proposed. The radiating structure is composed of a rectangular microstrip patch antenna exciting an L-shaped slot etched on the ground plane. The feed position is optimized to get better impedance match for the higher range of the UWB spectrum, while a step in the slot, realized in the ground plane, is employed to extend the lower limit of the bandwidth so as to cover the 2.4 GHz WLAN frequency band. Using these design solutions the antenna bandwidth is successfully extended to 140% so as to cover both the WLAN and the UWB spectrum.
Young Adults, Technology, and Weight Loss: A Focus Group Study
Authors: Stephens Janna , Moscou-Jackson Gyasi , Allen Jerilyn K.
Published: February 2015

Overweight and obesity are a major concern in young adults. Technology has been integrated into many weight loss interventions; however little is known about the use of this technology in young adults. The purpose of this study was to explore through focus group sessions the opinions of young adults on the use of technology for weight loss. A total of 17 young adults, between 18 and 25 years of age, participated in three focus group sessions. Major results indicated that young adults have very little knowledge on the use of Smartphone technology for weight loss but would like to use this type of technology to help them lose weight. Results also indicated that young adults struggle to make healthy food choices and have priorities that outweigh exercise and they need support and guidance to make better decisions. In conclusion, young adults would be open to using Smartphone technology for weight loss but also need feedback and guidance to help make healthy decisions.
Water Soluble Aluminum Paste Using Polyvinyl Alcohol for Silicon Solar Cells
Authors: Uzum Abdullah , Ashikaga Taiki , Noguchi Takuma , Kanda Hiroyuki , Matsuoka Toshifumi , Nakanishi Toru , Fukui Hidehito , Harada Tomitaro , Ito Seigo
Published: February 2015

Screen-printing aluminum is still dominantly used in the solar cell fabrication process. Ethyl cellulose is one of the main contents of screen-printing pastes that require dichloromethane for its cleaning process, a substance renowned for being extremely toxic and threatening to the human body. Developing environmental friendly aluminum pastes is essential in order to provide an alternative to the commercial pastes. In this work, new, nontoxic polyvinyl alcohol-based aluminum pastes are introduced. Polyvinyl alcohol was used as a soluble polymer that can be synthesized without saponification and that is also soluble in water. Three different pastes were developed using different recipes including many aluminum particle sizes varying from 3.0 to 45 μm, aluminum oxide with particle sizes between 35 and 50 μm, and acetic acid. Evaluation of the pastes was carried out by Scanning Electron Microscope (SEM) image analysis, sheet resistance measurements, and fabricating silicon solar cells using each paste. Solar cells with 15.6% efficiency were fabricated by nonvacuum processing on CZ-Si p-type wafers using developed aluminum pastes on the back side.
Phosphorus Sorption Kinetics in Reclaimed Lignite Mine Soils under Different Age Stands ofRobinia pseudoacaciaL. in Northeast Germany
Authors: Slazak Anna , Freese Dirk
Published: February 2015

The objectives of the work were to study phosphorus (P) dynamics in postmining soils under short rotation coppices at different stages ofRobinia pseudoacaciaL. growth (2, 3, 4, and 14 years old). From the results obtained, the amount of total P, total organic P, plant available P, and P stock increased with increasing age ofR. pseudoacacia. However, values were very low compared to that recommended for optimum plant growth, reflecting a general deficit in P. Additionally, the P sorption and desorption processes were investigated. The total P sorption capacity obtained from the laboratory experiments was on average, 2.5 times greater for soils under the oldestR. pseudoacaciathan values measured at the younger sites. Values of P saturation factor (α) were comparatively lower compared to that reported in the literature. This may be attributed primarily to the less P saturation of the postmining soils, coupled with rather small contents of oxalate ironFeoxand aluminiumAlox(sum of 47 mmol kg−1). Results demonstrate significant difference between 2 and 14 years oldR. pseudoacacia; thus establishing of short rotation coppice (SRC) on degraded marginal sites may be a valuable method of soil reclamations.
Analysis and Design of Leaky-Wave Antenna with Low SLL Based on Half-Mode SIW Structure
Authors: Guo Jiaying , Li Zheng , Wang Junhong , Chen Meie , Zhang Zhan
Published: February 2015

This paper presents a novel leaky-wave antenna based on the Half-Mode Substrate Integrated Waveguide (HMSIW) structure with low side lobe level. The effect of the structural parameters of the LWAs on the radiation performances is studied. Using beam-forming technique, the leakage loss factorαalong the radiation aperture is designed in a tapered way by controlling the aperture depth along the structure. This controls the radiated power along the antenna aperture and finally achieves the radiation pattern with low SLL. Furthermore, the antenna structure is optimized to get an even lower SLL.
Kinetics of NiO and NiCl2 Hydrogen Reduction as Precursors and Properties of Produced Ni/Al2O3 and Ni‐Pd/Al2O3 Catalysts
Authors: Sokić Miroslav , Kamberović Željko , Nikolić Vesna , Marković Branislav , Korać Marija , Anđić Zoran , Gavrilovski Milorad
Published: February 2015

The objects of this investigation were the comparative kinetic analysis of the NiO and NiCl2 reduction by hydrogen during an induction period and elimination of the calcination during the synthesis of Ni/Al2O3 catalysts. The effect of temperature and time on NiO and NiCl2 reduction degrees was studied. Avrami I equation was selected as the most favorable kinetic model and used to determine activation energy of the NiO and NiCl2 reduction for the investigated temperature range (623–923 K) and time intervals (1–5 minutes). The investigation enabled reaching conclusions about the reaction ability and rate of the reduction processes. Afterward, Ni/Al2O3 catalysts were obtained by using oxide and chloride precursor for Ni. The catalysts were supported on alumina‐based foam and prepared via aerosol route. Properties of the samples before and after low‐temperature hydrogen reduction (633 K) were compared. Obtained results indicated that the synthesis of Ni/Al2O3 catalysts can be more efficient if chloride precursor for Ni is directly reduced by hydrogen during the synthesis process, without the calcination step. In addition, Ni‐Pd/Al2O3 catalysts with different metal content were prepared by using chloride precursors. Lower reduction temperature was utilized and the chlorides were almost completely reduced at 533 K.
Pelvic Surgical Site Infections in Gynecologic Surgery
Authors: Lachiewicz Mark P. , Moulton Laura J. , Jaiyeoba Oluwatosin
Published: February 2015

The development of surgical site infection (SSI) remains the most common complication of gynecologic surgical procedures and results in significant patient morbidity. Gynecologic procedures pose a unique challenge in that potential pathogenic microorganisms from the skin or vagina and endocervix may migrate to operative sites and can result in vaginal cuff cellulitis, pelvic cellulitis, and pelvic abscesses. Multiple host and surgical risk factors have been identified as risks that increase infectious sequelae after pelvic surgery. This paper will review these risk factors as many are modifiable and care should be taken to address such factors in order to decrease the chance of infection. We will also review the definitions, microbiology, pathogenesis, diagnosis, and management of pelvic SSIs after gynecologic surgery.
Properties and Microstructures of Sn-Ag-Cu-X Lead-Free Solder Joints in Electronic Packaging
Authors: Sun Lei , Zhang Liang
Published: February 2015

SnAgCu solder alloys were considered as one of the most popular lead-free solders because of its good reliability and mechanical properties. However, there are also many problems that need to be solved for the SnAgCu solders, such as high melting point and poor wettability. In order to overcome these shortcomings, and further enhance the properties of SnAgCu solders, many researchers choose to add a series of alloying elements (In, Ti, Fe, Zn, Bi, Ni, Sb, Ga, Al, and rare earth) and nanoparticles to the SnAgCu solders. In this paper, the work of SnAgCu lead-free solders containing alloying elements and nanoparticles was reviewed, and the effects of alloying elements and nanoparticles on the melting temperature, wettability, mechanical properties, hardness properties, microstructures, intermetallic compounds, and whiskers were discussed.
TRAIL Modulates the Immune System and Protects against the Development of Diabetes
Authors: Bossi Fleur , Bernardi Stella , Zauli Giorgio , Secchiero Paola , Fabris Bruno
Published: February 2015

TRAIL or tumor necrosis factor (TNF) related apoptosis-inducing ligand is a member of the TNF superfamily of proteins, whose best characterized function is the induction of apoptosis in tumor, infected, or transformed cells through activation of specific receptors. In nontransformed cells, however, the actions of TRAIL are less well characterized. Recent studies suggest that TRAIL may be implicated in the development and progression of diabetes. Here we review TRAIL biological actions, its effects on the immune system, and how and to what extent it has been shown to protect against diabetes.
Identification of Prior Factors Influencing the Mode Choice of Short Distance Travel
Authors: Li Ming , Song Guohua , Cheng Ying , Yu Lei
Published: February 2015

Short distance trips are defined as any trips shorter than or equal to 5 kilometers, which have been found to be a big contributor to the traffic congestion problem. This paper is intended to analyze factors that influence the mode choice of short distance travels in order to help reduce short distance trips by cars. A survey is conducted at two typical kinds of residential areas, one with a high proportion of short distance car trips and another one with a low proportion. Then, by applying the structural equation modeling, it is found that the age, the household income, and the vehicle ownerships have a significant effect on the mode choice of short distance travels. Besides, among residents of the same type (same age, household income, and vehicle ownerships) in surveyed areas, those in the area with a better green-mode travel environment account for a higher proportion choosing the green mode than those in other areas. Based on this result, it is concluded that a better green-mode travel environment leads to a higher proportion of green-mode travels. In the end, the paper shows residents’ stated willingness to change travel modes from cars to the green mode.