bluuebunny/crossref_metadata_2025 huggingface dataset:
Measuring diffusion coefficients of dissolved He and Ar in three potential clay host formations: Boom Clay, Callovo-Oxfordian Clay and Opalinus Clay
Authors: Jacops E. , Maes N. , Bruggeman C. , Grade A.
Published: June 2016

For the long-term management of high- and intermediate-level radioactive waste and/or spent fuel, many countries prefer disposal in a geological repository. In Belgium, Switzerland and France, argillaceous formations are being explored as potential host formations for this purpose. In this context, knowledge of the diffusion coefficient of He is relevant within two research areas: first, diffusion coefficients are used in safety calculations to evaluate the balance between gas generation (mainly H
2
) and gas dissipation; and, second, the diffusion coefficients of He and Ar are needed in the diffusion models of natural tracers. Owing to the lack of data on the diffusion coefficients of He and Ar for the different clay host formations, diffusion experiments with dissolved He and Ar were performed on Boom Clay, Opalinus Clay and Callovo-Oxfordian Clay. Samples were confined in a diffusion cell, and diffusion coefficients were measured by using the double through-diffusion technique. The diffusion coefficients (
D
p
or
D
pore
) for He in Boom Clay, Callovo-Oxfordian Clay and Opalinus Clay are 12.6×10
−10
, 4.51×10
−10
and 7.13×10
−10
m
2
s
−1
, respectively. The diffusion coefficients for Ar in Boom Clay, Callovo-Oxfordian Clay and Opalinus Clay are 18.6×10
−11
, 4.06×10
−11
and 3.65×10
−11
m
2
s
−1
, respectively.
Participatory networking
Authors: Ferguson Andrew D. , Guha Arjun , Liang Chen , Fonseca Rodrigo , Krishnamurthi Shriram
Published: June 2016

We present the design, implementation, and evaluation of an API for applications to control a software-defined network (SDN). Our API is implemented by an OpenFlow controller that delegates read and write authority from the network's administrators to end users, or applications and devices acting on their behalf. Users can then work with the network, rather than around it, to achieve better performance, security, or predictable behavior. Our API serves well as the next layer atop current SDN stacks. Our design addresses the two key challenges: how to safely decompose control and visibility of the network, and how to resolve conflicts between untrusted users and across requests, while maintaining baseline levels of fairness and security. Using a real OpenFlow testbed, we demonstrate our API's feasibility through microbenchmarks, and its usefulness by experiments with four real applications modified to take advantage of it.
FCP
Authors: Han Dongsu , Grandl Robert , Akella Aditya , Seshan Srinivasan
Published: June 2016

Transport protocols must accommodate diverse application and network requirements. As a result, TCP has evolved over time with new congestion control algorithms such as support for generalized AIMD, background flows, and multipath. On the other hand, explicit congestion control algorithms have been shown to be more efficient. However, they are inherently more rigid because they rely on in-network components. Therefore, it is not clear whether they can be made flexible enough to support diverse application requirements. This paper presents a flexible framework for network resource allocation, called FCP, that accommodates diversity by exposing a simple abstraction for resource allocation. FCP incorporates novel primitives for end-point flexibility (
aggregation
and
preloading
) into a single framework and makes economics-based congestion control practical by explicitly handling load variations and by decoupling it from actual billing. We show that FCP allows evolution by accommodating diversity and ensuring coexistence, while being as efficient as existing explicit congestion control algorithms.
Forwarding metamorphosis
Authors: Bosshart Pat , Gibb Glen , Kim Hun-Seok , Varghese George , McKeown Nick , Izzard Martin , Mujica Fernando , Horowitz Mark
Published: June 2016

In Software Defined Networking (SDN) the control plane is physically separate from the forwarding plane. Control software programs the forwarding plane (e.g., switches and routers) using an open interface, such as OpenFlow. This paper aims to overcomes two limitations in current switching chips and the OpenFlow protocol: i) current hardware switches are quite rigid, allowing ``Match-Action'' processing on only a fixed set of fields, and ii) the OpenFlow specification only defines a limited repertoire of packet processing actions. We propose the RMT (reconfigurable match tables) model, a new RISC-inspired pipelined architecture for switching chips, and we identify the essential minimal set of action primitives to specify how headers are processed in hardware. RMT allows the forwarding plane to be changed in the field without modifying hardware. As in OpenFlow, the programmer can specify multiple match tables of arbitrary width and depth, subject only to an overall resource limit, with each table configurable for matching on arbitrary fields. However, RMT allows the programmer to modify
all
header fields much more comprehensively than in OpenFlow. Our paper describes the design of a 64 port by 10 Gb/s switch chip implementing the RMT model. Our concrete design demonstrates, contrary to concerns within the community, that flexible OpenFlow hardware switch implementations are feasible at almost no additional cost or power.
Got loss? Get zOVN!
Authors: Crisan Daniel , Birke Robert , Cressier Gilles , Minkenberg Cyriel , Gusat Mitch
Published: June 2016

Datacenter networking is currently dominated by two major trends. One aims toward lossless, flat layer-2 fabrics based on Converged Enhanced Ethernet or InfiniBand, with benefits in efficiency and performance. The other targets flexibility based on Software Defined Networking, which enables Overlay Virtual Networking. Although clearly complementary, these trends also exhibit some conflicts: In contrast to physical fabrics, which avoid packet drops by means of flow control, practically all current virtual networks are lossy. We quantify these losses for several common combinations of hypervisors and virtual switches, and show their detrimental effect on application performance. Moreover, we propose a zero-loss Overlay Virtual Network (zOVN) designed to reduce the query and flow completion time of latency-sensitive datacenter applications. We describe its architecture and detail the design of its key component, the zVALE lossless virtual switch. As proof of concept, we implemented a zOVN prototype and benchmark it with Partition-Aggregate in two testbeds, achieving an up to 15-fold reduction of the mean completion time with three widespread TCP versions. For larger-scale validation and deeper introspection into zOVN, we developed an OMNeT++ model for accurate cross-layer simulations of a virtualized datacenter, which confirm the validity of our results.
Maple
Authors: Voellmy Andreas , Wang Junchang , Yang Y Richard , Ford Bryan , Hudak Paul
Published: June 2016

Software-Defined Networking offers the appeal of a simple, centralized programming model for managing complex networks. However, challenges in managing low-level details, such as setting up and maintaining correct and efficient forwarding tables on distributed switches, often compromise this conceptual simplicity. In this pa- per, we present Maple, a system that simplifies SDN programming by (1) allowing a programmer to use a standard programming language to design an arbitrary,
centralized
algorithm, which we call an
algorithmic policy
, to decide the behaviors of an entire network, and (2) providing an abstraction that the programmer-defined, centralized policy runs, conceptually, "afresh" on every packet entering a network, and hence is oblivious to the challenge of translating a high-level policy into sets of rules on distributed individual switches. To implement algorithmic policies efficiently, Maple includes not only a highly-efficient multicore scheduler that can scale efficiently to controllers with 40+ cores, but more importantly a novel
tracing
runtime optimizer that can automatically record reusable policy decisions, offload work to switches when possible, and keep switch flow tables up-to-date by dynamically tracing the dependency of policy decisions on packet contents as well as the
environment
(system state). Evaluations using real HP switches show that Maple optimizer reduces HTTP connection time by a factor of 100 at high load. During simulated benchmarking, Maple scheduler, when not running the optimizer, achieves a throughput of over 20 million new flow requests per second on a single machine, with 95-percentile latency under 10 ms.
Verifiable auctions for online ad exchanges
Authors: Angel Sebastian , Walfish Michael
Published: June 2016

This paper treats a critical component of the Web ecosystem that has so far received little attention in our community: ad exchanges. Ad exchanges run auctions to sell publishers' inventory-space on Web pages-to advertisers who want to display ads in those spaces. Unfortunately, under the status quo, the parties to an auction cannot check that the auction was carried out correctly, which raises the following more general question: how can we create verifiability in low-latency, high-frequency auctions where the parties do not know each other? We address this question with the design, prototype implementation, and experimental evaluation of VEX. VEX introduces a technique for efficient, privacy-preserving integer comparisons; couples these with careful protocol design; and adds little latency and tolerable overhead.
Is information-centric multi-tree routing feasible?
Authors: Carzaniga Antonio , Khazaei Koorosh , Papalini Michele , Wolf Alexander L.
Published: June 2016

We have argued that an information-centric network should natively support publish/subscribe event notification in addition to on-demand content delivery. We have also argued that both primitives could use the same forwarding information base and, furthermore, that both primitives can easily support addresses that are more expressive than simple hierarchical names. In this paper we present a concrete routing scheme that realizes this: "push" as well as "pull" communication; anycast as well as multicast; and descriptor-based (as opposed to name-based) addressing. The scheme is founded on multiple tree covers that can be arranged and composed hierarchically following the structure of network domains. On each tree, the scheme combines addresses so as to reduce forwarding state. We demonstrate the feasibility and scalability of the scheme through simulations on Internet-scale workloads in realistic network settings.
D-tunes
Authors: P N Shankaranarayanan , Sivakumar Ashiwan , Rao Sanjay , Tawarmalani Mohit
Published: June 2016

Modern internet applications have resulted in users sharing data with each other in an interactive fashion. These applications have very stringent service level agreements (SLAs) which place tight constraints on the performance of the underlying geo-distributed datastores. Deploying these systems in the cloud to meet such constraints is a challenging task, as application architects have to strike an optimal balance among different contrasting objectives such as maintaining consistency between multiple replicas, minimizing access latency and ensuring high availability. Achieving these objectives requires carefully configuring a number of low-level parameters of the datastores, such as the number of replicas, which DCs contain which data, and the underlying consistency protocol parameters. In this work, we adopt a systematic approach where we develop analytical models that capture the performance of a datastore based on application workload and build a system that can automatically configure the datastore for optimal performance.
Contextualized information-centric home network
Authors: Biswas Trisha , Chakraborti Asit , Ravindran Ravishankar , Zhang Xinwen , Wang Guoqiang
Published: June 2016

We deploy information-centric networks (ICN) to serve several applications including content distribution, vehicle-to-vehicle communication (V2V), home networks (homenet), and sensor networks. These applications require policy and context-based interaction between service producers and consumers. We visualize the ICN service layer as a contextualized information-centric bus (CIBUS), over which diverse sets of service producers and consumers co-exist. We develop a prototype and demonstrate several desirable features of ICN for homenets such as contextual service publishing and subscription, zero-configuration based node and service discovery, policy based routing and forwarding with name-based firewall, and device-to-device communication. Furthermore the prototype is applicable to both ad hoc and infrastructure settings, and can deal with diverse devices and services.
Automated configuration and measurement of emulated networks with AutoNetkit
Authors: Knight Simon
Published: June 2016

Emulated networks enable educators, researchers, and operators to conduct realistic network scenarios on commodity hardware. However each network device must be configured, typically in a low-level syntax. This time-consuming and error-prone process limits scalability and discourages repeated experimentation.

This demonstration will show a platform to automate emulated network configuration and measurement, making large-scale network experimentation accessible.
A large-scale multipath playground for experimenters and early adopters
Authors: Németh Felicián , Sonkoly Balázs , Csikor Levente , Gulyás András
Published: June 2016

Multipath TCP is an experimental transport protocol with remarkable recent past and non-negligible future potential. However the lack of available large-scale testbeds and publicly accessible multiple paths grossly prohibits the adoption of the technology. Here, we demonstrate a large-scale multipath playground deployed on PlanetLab Europe, which can be used either by experimenters and researchers to test and verify their multipath-related ideas (e.g. enhancing congestion control, fairness or even the arrangement of multiple paths) and also by early adopters to enhance their Internet connection even if single-homed.
Towards fast regular expression matching in practice
Authors: Wang Kai , Li Jun
Published: June 2016

Regular expression matching is popular in today's network devices with deep inspection function, but due to lack of algorithmic scalability, it is still the performance bottleneck in practical network processing. To address this problem, our method first partition regular expression patterns into simple segments to avoid state explosion, and then compile these segments into a compact data structure to achieve fast matching. Preliminary experiments illustrate that our matching engine scales linearly with the size of the real-world pattern set, and outperforms state-of-the-art solutions.
In-network caching assisted wireless AP storage management
Authors: Ming Zhongxing , Xu Mingwei , Wang Dan
Published: June 2016

The goal of this paper is to improve wireless AP caching by leveraging in-network caching. We observe that by treating routers as an in-network storage extension, we can relieve the storage limitation of APs. The unique challenge is that APs and routers cannot have a full collaboration, which makes the problem different from traditional cooperative caching problems. We study how APs can optimize caching decisions by using in-network caching information without controlling routers.
CSPAN
Authors: Wu Zhe , Butkiewicz Michael , Perkins Dorian , Katz-Bassett Ethan , Madhyastha Harsha V.
Published: June 2016

Existing cloud computing platforms leave it up to applications to deal with the complexities associated with data replication and propagation across data centers. In our work, we propose the
CSPAN
key-value store to instead export a unified view of storage services in several geographically distributed data centers. To minimize the cost incurred by application providers, we combine two principles. First,
CSPAN
spans the data centers of multiple cloud providers. Second,
CSPAN
judiciously trades off the lower latencies and the higher storage and data propagation costs based on an application's anticipated workload, latency goals, and consistency requirements.
Which flows are hiding behind my wildcard rule?
Authors: Wette Philip , Karl Holger
Published: June 2016

In OpenFlow, multiple switches share the same control plane which is centralized at what is called the OpenFlow controller. A switch only consists of a forwarding plane. Rules for forwarding individual packets (called
flow entries
in OpenFlow) are pushed from the controller to the switches.

In a network with a high arrival rate of new flows, such as in a data center, the control traffic between the switch and controller can become very high. As a consequence, routing of new flows will be slow. One way to reduce control traffic is to use wildcarded flow entries. Wildcard flow entries can be used to create default routes in the network. However, since switches do not keep track of flows covered by a wildcard flow entry, the controller no longer has knowledge about individual flows. To find out about these individual flows we propose an extension to the current OpenFlow standard to enable packet sampling of wildcard flow entries.
Cooperation policies for efficient in-network caching
Authors: Wang Liang , Bayhan Suzan , Kangasharju Jussi
Published: June 2016

Caching is a key component of information-centric networking, but most of the work in the area focuses on simple en-route caching with limited cooperation between the caches. In this paper we model cache cooperation under a game theoretical framework and show how cache cooperation policy can allow the system to converge to a Pareto optimal configuration. Our work shows how cooperation impacts network caching performance and how it takes advantage of the structural properties of the underlying network.
An empirical study of analog channel feedback
Authors: Shen Wei-Liang , Lin Kate Ching-Ju , Chen Ming-Syan
Published: June 2016

Exchanging the channel state information (CSI) in a multiuser WLAN is considered an extremely expensive overhead. A possible solution to reduce the overhead is to notify the analog value of the CSI, which is also known as
analog channel feedback
. It however only allows nodes to overhear an imperfect channel information. While some previous studies have theoretically analyzed the performance of analog channel feedback, this work aims at addressing issues of realizing it in practice and empirically demonstrating its effectiveness. Our prototype implementation using USRP-N200 shows that analog channel feedback produces a small error comparable to that of estimating CSI using reciprocity, but however can be applied to more general scenarios.
Characterizing and detecting malicious crowdsourcing
Authors: Wang Tianyi , Wang Gang , Li Xing , Zheng Haitao , Zhao Ben Y.
Published: June 2016

Popular Internet services in recent years have shown that remarkable things can be achieved by harnessing the power of the masses. However, crowd-sourcing systems also pose a real challenge to existing security mechanisms deployed to protect Internet services, particularly those tools that identify malicious activity by detecting activities of automated programs such as CAPTCHAs.

In this work, we leverage access to two large crowdturfing sites to gather a large corpus of ground-truth data generated by crowdturfing campaigns. We compare and contrast this data with "organic" content generated by normal users to identify unique characteristics and potential signatures for use in real-time detectors. This poster describes first steps taken focused on crowdturfing campaigns targeting the Sina Weibo microblogging system. We describe our methodology, our data (over 290K campaigns, 34K worker accounts, 61 million tweets...), and some initial results.
Harnessing receive diversity in distributed multi-user MIMO networks
Authors: Chen Bo-Si , Lin Kate Ching-Ju , Wei Hung-Yu
Published: June 2016

In existing multiuser MIMO (MU-MIMO) MAC protocols, a multi-antenna node sends as many concurrent streams as possible once it wins the contention. Though such a scheme allows nodes to utilize the multiplex gain of a MIMO system, it however fails to leverage receive diversity gains provided by multiple receive antennas across nodes. We introduce Multiplex-Diversity Medium Access (MDMA), a MU-MIMO MAC protocol that achieves both the multiplex gain and the receive diversity gain at the same time. Instead of letting a node pair use all the available degrees of freedom, MDMA allows as many contending node pairs to communicate concurrently as possible and share all the degrees of freedom. It hence can exploit the antennas equipped on different receivers to further provide some of concurrent streams more receive diversity, without losing the achievable multiplex gain. We implement a prototype on software radios to demonstrate the throughput gain of MDMA.
To 4,000 compute nodes and beyond
Authors: Awara Karim , Jamjoom Hani , Kanlis Panos
Published: June 2016

The explosive growth of "big data" is giving rise to a new breed of large scale graph systems, such as Pregel. This poster describes our ongoing work in characterizing and minimizing the communication cost of Bulk Synchronous Parallel (BSP) graph mining systems, like Pregel, when scaling to 4,096 compute nodes. Existing implementations generally assume a fixed communication cost. This is sufficient in small deployments as the BSP programming model (i.e., overlapping computation and communication) masks small variations in the underlying network. In large scale deployments, such variations can dominate the overall runtime characteristics. In this poster, we first quantify the impact of network communication on the total compute time of a Pregel system. We then propose an efficient vertex placement strategy that subsamples highly connected vertices and applies the Reverse Cuthill-McKee (RCM) algorithm to efficiently partition the input graph and place partitions closer to each other based on their expected communication patterns. We finally describe a vertex replication strategy to further reduce communication overhead.
Topology-aware content-centric networking
Authors: Zhang Xinggong , Niu Tong , Lao Feng , Guo Zongming
Published: June 2016

Making data the first class entity, Information-Centric Networking (ICN) replaces conventional
host-to-host
model with
content sharing
model. However, the huge amount of content and the volatility of replicas cached across the Internet pose significant challenges for addressing content only by name. In this paper, we propose a topology-aware name-based routing protocol which combines the benefits of location-oriented routing and content-centric routing together. We adopt a URL-like naming scheme, which defines register locations and content identifier. Node with copies sends Register messages towards a register using location-oriented routing protocols. All en-path routers record forwarding entries in forwarding table (FIB) as the "bread crumb" to this content. Following the bread crumb, routers know the "best" topology path to the available copies. An Interest is either forwarded towards a "known" copy by the content identifier, or towards the register nodes where it would find the bread crumb to the "best" copies. Compared with the existing flooding or name resolution methods, Our design shows a good potential in terms of scalability, availability and overhead.
Protecting Against Velocity-Based, Proximity-Based, and External Event Attacks in Location-Centric Social Networks
Authors: Ghinita Gabriel , Damiani Maria Luisa , Silvestri Claudio , Bertino Elisa
Published: June 2016

Mobile devices with positioning capabilities allow users to participate in novel and exciting location-based applications. For instance, users may track the whereabouts of their acquaintances in location-aware social networking applications (e.g., Foursquare). Furthermore, users can request information about landmarks in their proximity. Such scenarios require users to report their coordinates to other parties, which may not be fully trusted. Reporting precise locations may result in serious privacy violations, such as disclosure of lifestyle details, sexual orientation, and so forth. A typical approach to preserve location privacy is to generate a
cloaking region (CR)
that encloses the user position. However, if locations are continuously reported, an attacker can correlate CRs from multiple timestamps to accurately pinpoint the user position within a CR.

In this work, we protect against a broad range of attacks that breach location privacy using knowledge about (1) maximum user velocity, (2) external events that may occur outside the process of self-reporting locations (e.g., social network posts tagged by peers), and (3) information about mutual proximity between users. Assume user
u
who reports two consecutive cloaked regions
A
and
B
. We consider two distinct protection scenarios: in the first case, the attacker does not have information about the sensitive locations on the map, and the objective is to ensure that
u
can reach
some
point in
B
from
any
point in
A
; in the second case, the attacker knows the placement of sensitive locations, and the objective is to ensure that
u
can reach
any
point in
B
from
any
point in
A
. We propose spatial and temporal cloaking transformations to preserve user privacy, and we show experimentally that privacy can be achieved without significant quality-of-service deterioration.
Looking back and looking to the future
Authors: Gil Yolanda
Published: June 2016

On July 1, I will be stepping down as SIGAI Chair following elections for our SIG. In this article, I reflect on my time as Chair, describe the election process, and introduce the future leaders of our SIG.
Novel hierarchical feature selection algorithms for predicting genes' aging-related function
Authors: Wan Cen
Published: June 2016

Hierarchical Feature Selection (HFS) is an under-explored subarea of machine learning/ data mining. Unlike conventional (flat) feature selection algorithms, HFS algorithms work by exploiting hierarchical (generalizationspecialization) relationships between features, in order to improve the predictive accuracy of classifiers. The basic idea is to remove hierarchical redundancy between features, where the presence of a feature in an instance implies the presence of all ancestors of that feature in that instance. By using an HFS algorithm to select a feature subset where the hierarchical redundancy among features is eliminated or reduced, and then giving only the selected feature subset to a classification algorithm, it is possible to improve the predictive accuracy of classification algorithms. In terms of applications, this thesis focuses on datasets of aging-related genes. This type of dataset is an interesting type of application for machine learning/data mining methods due to the technical difficulty and ethical issues associated with doing aging experiments with humans and the strategic importance of research on the biology of aging, since old age is the greatest risk factor for a number of diseases, but is still a not well understood biological process.
Bayesian aggregation of evidence for detection and characterization of patterns in multiple noisy observations
Authors: Tandon Prateek
Published: June 2016

Bayesianism is a premier representation for encoding intelligence in robotic sensing. My thesis develops Bayesian Aggregation (BA), a machine learning pipeline for understanding patterns in noisy sensor data and extracting structure from multiple correlated observations.
Introduction to this special issue
Authors: Chow Chi-Yin , Huang Zhuojie
Published: June 2016

Public health-related issues (e.g., illness, pollution, and healthcare) are important social issues for governments and researchers. Many of these issues have strong spatial and/or spatio-temporal components, for example, epidemics of infectious disease. It is a highly topic to investigate how to apply GIS technologies and research findings to public health access, processes, analysis, and decision-making. This special issue consists of five contributions that address different problems in the research area of GIS and public health.
From farm to fork
Authors: Hu Kun , Edlund Stefan , Davis Matthew , Kaufman James
Published: June 2016

Foodborne disease is a global public health problem that affects millions of people every year. During a foodborne illness outbreak, rapid identification of contaminated food is vital to minimize illness, loss and impact on society. Public health officials face a significant challenge and long delays in obtaining critical information to help identify a contaminated product using traditional methods such as surveys and questionnaires. We propose a novel approach mapping geo-coded sales data against geo-coded confirmed case reports, which has the potential to reduce the time required for foodborne illness investigation. Using real grocery retail scanner data with spatial information from Germany, we have implemented a likelihood-based framework to study how such spatial data can be used to accelerate the investigation during the early stages of an outbreak. Our analysis shows that after receiving as few as 10 laboratory confirmed case reports it is possible to narrow the investigation to approximately 12 suspect products with the contaminated product included in this subset 90% of the time for approximately 80% of food products studied.
SarcOptiM for ImageJ: high-frequency online sarcomere length computing on stimulated cardiomyocytes
Authors: Pasqualin Côme , Gannier François , Yu Angèle , Malécot Claire O. , Bredeloux Pierre , Maupoil Véronique
Published: June 2016

Accurate measurement of cardiomyocyte contraction is a critical issue for scientists working on cardiac physiology and physiopathology of diseases implying contraction impairment. Cardiomyocytes contraction can be quantified by measuring sarcomere length, but few tools are available for this, and none is freely distributed. We developed a plug-in (SarcOptiM) for the ImageJ/Fiji image analysis platform developed by the National Institutes of Health. SarcOptiM computes sarcomere length via fast Fourier transform analysis of video frames captured or displayed in ImageJ and thus is not tied to a dedicated video camera. It can work in real time or offline, the latter overcoming rotating motion or displacement-related artifacts. SarcOptiM includes a simulator and video generator of cardiomyocyte contraction. Acquisition parameters, such as pixel size and camera frame rate, were tested with both experimental recordings of rat ventricular cardiomyocytes and synthetic videos. It is freely distributed, and its source code is available. It works under Windows, Mac, or Linux operating systems. The camera speed is the limiting factor, since the algorithm can compute online sarcomere shortening at frame rates >10 kHz. In conclusion, SarcOptiM is a free and validated user-friendly tool for studying cardiomyocyte contraction in all species, including human.
Peptidyl arginine deiminase-4-deficient mice are protected against kidney and liver injury after renal ischemia and reperfusion
Authors: Rabadi May , Kim Mihwa , D'Agati Vivette , Lee H. Thomas
Published: June 2016

We previously demonstrated that renal peptidyl arginine deiminase-4 (PAD4) is induced after renal ischemia and reperfusion (I/R) injury and exacerbates acute kidney injury (AKI) by increasing the renal tubular inflammatory response. Here, we tested whether genetic ablation of PAD4 attenuates renal injury and inflammation after I/R in mice. After renal I/R, PAD4 wild-type mice develop severe AKI with large increases in plasma creatinine, neutrophil infiltration, as well as significant renal tubular necrosis, apoptosis, and proinflammatory cytokine generation. In contrast, PAD4-deficient mice are protected against ischemic AKI with reduced real tubular neutrophil infiltration, renal tubular necrosis, and apoptosis. In addition, hepatic injury and inflammation observed in PAD4 wild-type mice after renal I/R are significantly attenuated in PAD4-deficient mice. We also show that increased renal tubular PAD4 expression after renal I/R is associated with translocation of PAD4 from the nucleus to the cytosol. Consistent with PAD4 cytosolic translocation, we show increased renal tubular cytosolic peptidyl-citrullination after ischemic AKI. Mechanistically, recombinant PAD4 treatment increased nuclear translocation of NF-κB in cultured human as well as murine proximal tubule cells that is inhibited by a PAD4 inhibitor (2-chloroamidine). Taken together, our studies further support the hypothesis that renal tubular PAD4 plays a critical role in renal I/R injury by increasing the renal tubular inflammatory response and neutrophil infiltration after renal I/R perhaps by interacting with the proinflammatory transcription factor NF-κB in the cytosol and promoting its nuclear translocation.
Necessary and Sufficient Conditions for Circle Formations of Mobile Agents with Coupling Delay via Sampled-Data Control
Authors: Zhao Jianwei , Hu Hongxiang , Wang Chen , Xie Guangming
Published: June 2016

A circle forming problem for a group of mobile agents governed by first-order system is investigated, where each agent can only sense the relative angular positions of its neighboring two agents with time delay and move on the one-dimensional space of a given circle. To solve this problem, a novel decentralized sampled-data control law is proposed. By combining algebraic graph theory with control theory, some necessary and sufficient conditions are established to guarantee that all the mobile agents form a pregiven circle formation asymptotically. Moreover, the ranges of the sampling period and the coupling delay are determined, respectively. Finally, the theoretical results are demonstrated by numerical simulations.
Chronic Alcohol Intoxication and Cortical Ischemia: Study of Their Comorbidity and the Protective Effects of Minocycline
Authors: Fontes-Júnior Enéas Andrade , Maia Cristiane Socorro Ferraz , Fernandes Luanna Melo Pereira , Gomes-Leal Walace , Costa-Malaquias Allan , Lima Rafael Rodrigues , Prediger Rui Daniel , Crespo-López Maria Elena
Published: June 2016

Chronic alcohol intoxication (CAI) increases both morbidity and mortality of stroke patients. Despite the high prevalence of CAI and ischemic stroke, studies addressing their comorbidity and/or protective alternatives remain scarce. Thus, the influence of CAI on both stroke outcome and minocycline treatment (recognized for its neuroprotective effect) was investigated. Female Wistar rats (35 days old) were treated with water or ethanol (6.5 g/kg/day, 22.5% w/v) for 55 days. Then, focal ischemia was induced by endothelin‐1 in the motor cortex. Two hours later, four doses of 50 mg/kg of minocycline every 12 hours followed by five doses of 25 mg/kg every 24 hours were administered. Behavioral performance (open field and rotarod tests) and immunohistochemical (cellular density, neuronal death, and astrocytic activation) and biochemical (lipid peroxidation and nitrite levels) analyses were performed. CAI increased motor disruption, nitrite and lipid peroxidation levels, and neuronal loss caused by ischemia, whereas it reduced the astrogliosis. Minocycline was effective in preventing the motor and tissue damage caused by stroke. However, these effects were attenuated when CAI preceded stroke. Our data suggest that CAI beginning in adolescence contributes to a worse outcome in ischemic stroke survivors and reduces the benefits of minocycline, possibly requiring adjustments in therapy.
SmartCop: Enabling Smart Traffic Violations Ticketing in Vehicular Named Data Networks
Authors: Ahmed Syed Hassan , Yaqub Muhammad Azfar , Bouk Safdar Hussain , Kim Dongkyun
Published: June 2016

Recently, various applications for Vehicular Ad hoc Networks (VANETs) have been proposed and smart traffic violation ticketing is one of them. On the other hand, the new Information-Centric Networking (ICN) architectures have emerged and been investigated into VANETs, such as Vehicular Named Data Networking (VNDN). However, the existing applications in VANETs are not suitable for VNDN paradigm due to the dependency on a“named content”instead of a current“host-centric”approach. Thus, we need to design the emerging and new architectures for VNDN applications. In this paper, we propose a smart traffic violation ticketing (TVT) system for VNDN, named asSmartCop, that enables a cop vehicle (CV) to issue tickets for traffic violation(s) to the offender(s) autonomously, once they are in the transmission range of that CV. The ticket issuing delay, messaging cost, and percentage of violations detected for varying number of vehicles, violators, CVs, and vehicles speeds are estimated through simulations. In addition, we provide a road map of future research directions for enabling safe driving experience in future cars aided with VNDN technology.
Molecular Imaging for Comparison of Different Growth Factors on Bone Marrow-Derived Mesenchymal Stromal Cells’ Survival and ProliferationIn Vivo
Authors: Qiao Hongyu , Zhang Ran , Gao Lina , Guo Yanjie , Wang Jinda , Zhang Rongqing , Li Xiujuan , Li Congye , Chen Yundai , Cao Feng
Published: June 2016

Introduction. Bone marrow-derived mesenchymal stromal cells (BMSCs) have emerged as promising cell candidates but with poor survival after transplantation. This study was designed to investigate the efficacy of VEGF, bFGF, and IGF-1 on BMSCs’ viability and proliferation bothin vivoandin vitrousing bioluminescence imaging (BLI).Methods. BMSCs were isolated fromβ-actin-Fluc+transgenic FVB mice, which constitutively express firefly luciferase. Apoptosis was induced by hypoxia preconditioning for up to 24 h followed by flow cytometry and TUNEL assay. 106BMSCs with/without growth factors were injected subcutaneously into wild type FVB mice’s backs. Survival of BMSCs was longitudinally monitored using bioluminescence imaging (BLI) for 5 weeks. Protein expression of Akt, p-Akt, PARP, and caspase-3 was detected by Western blot.Results. Hypoxia-induced apoptosis was significantly attenuated by bFGF and IGF-1 compared with VEGF and control groupin vitro(P<0.05). When combined with matrigel, IGF-1 showed the most beneficial effects in protecting BMSCs from apoptosisin vivo.The phosphorylation of Akt had a higher ratio in the cells from IGF-1 group.Conclusion. IGF-1 could protect BMSCs from hypoxia-induced apoptosis through activation of p-Akt/Akt pathway.
Jiang Tang Xiao Ke Granule, a Classic Chinese Herbal Formula, Improves the Effect of Metformin on Lipid and Glucose Metabolism in Diabetic Mice
Authors: Zhang Yi , An Hong , Pan Si-Yuan , Zhao Dan-Dan , Zuo Jia-Cheng , Li Xiao-Ke , Gao Ya , Mu Qian-Qian , Yu Na , Ma Yue , Mo Fang-Fang , Gao Si-Hua
Published: June 2016

In the present study, the hypoglycemic, hypolipidemic, and antioxidative effects of metformin (MET) combined with Jiang Tang Xiao Ke (JTXK) granule derived from the “Di Huang Tang” were evaluated in mice with type 2 diabetes mellitus (DM) induced by high‐fat diet/streptozotocin. DM mice were orally treated with MET (0.19 g/kg) either alone or combined with different doses (1.75, 3.5, or 7 g/kg) of JTXK for 4 weeks. Results showed that the serum and hepatic glucose, lipids, and oxidative stress levels were elevated in DM mice, when compared with the normal mice. MET treatment decreased FBG and serum glucagon levels of DM mice. Combination treatment with MET and JTXK 3.5 g/kg increased the hypoglycemia and insulin sensitivity at 4 weeks when compared with the DM mice treated with MET alone. However, neither MET nor MET/JTXK treatment could completely reverse the hyperglycemia in DM mice. JTXK enhanced the serum triglyceride (TG) and hepatic lipid‐lowering effect of MET in a dose‐dependent manner in DM mice. JTXK 1.75 and 3.5 g/kg improved the hepatoprotective effect of MET in DM mice. Synergistic effect of combination treatment with MET and JTXK on antioxidant stress was also found in DM mice compared with MET alone.
Impact of Overlapping Fe/TiO2Prepared by Sol-Gel and Dip-Coating Process on CO2Reduction
Authors: Nishimura Akira , Zhao Xuyan , Hayakawa Takuya , Ishida Noriaki , Hirota Masafumi , Hu Eric
Published: June 2016

Fe-doped TiO2(Fe/TiO2) film photocatalyst was prepared by sol-gel and dip-coating process to extend its photoresponsivity to the visible spectrum. To promote the CO2reduction performance with the photocatalyst, some types of base materials used for coating Fe/TiO2, which were netlike glass fiber and Cu disc, were investigated. The characterization of prepared Fe/TiO2film coated on netlike glass fiber and Cu disc was analyzed by SEM and EPMA. In addition, the CO2reduction performance of Fe/TiO2film coated on netlike glass disc, Cu disc, and their overlap was tested under a Xe lamp with or without ultraviolet (UV) light, respectively. The results show that the concentration of produced CO increases by Fe doping irrespective of base material used under the illumination condition with UV light as well as that without UV light. Since the electron transfer between two overlapped photocatalysts is promoted, the peak concentration of CO for the Fe/TiO2double overlapping is approximately 1.5 times as large as the Fe/TiO2single overlapping under the illumination condition with UV light, while the promotion ratio is approximately 1.1 times under that without UV light.
Carbon Nanotube and Graphene Based Polyamide Electrospun Nanocomposites: A Review
Authors: Navarro-Pardo Fabiola , Martinez-Hernandez Ana L. , Velasco-Santos Carlos
Published: June 2016

Electrospinning is a unique and versatile technique to produce nanofibres; the facility to incorporate fillers has expanded its range of applications. This review gives a brief description of the process and the different polymers employed for obtaining nanofibres. Owing to the ability of fibrillation of polyamides, these polymers have resulted in a wide variety of interesting results obtained when using this technique; therefore these features are summarised. Additionally, because of the feasibility of incorporating carbon nanotubes and graphene in these nanofibres and the growing interest on these nanomaterials, this review focuses in the most common methods employed for their incorporation in electrospun polyamides. Several equipment setups used for the electrospinning of the nanofibres are explained. The outstanding electrical, optical, crystallinity, and mechanical properties obtained by a number of research groups are discussed. The potential applications of the resulting nanocomposites have also been explored.
Homotopy Analysis Solution for Magnetohydrodynamic Squeezing Flow in Porous Medium
Authors: Ullah Inayat , Rahim M. T. , Khan Hamid , Qayyum Mubashir
Published: June 2016

The aim of the present work is to analyze the magnetohydrodynamic (MHD) squeezing flow through porous medium using homotopy analysis method (HAM). Fourth-order boundary value problem is modeled through stream functionψ(r,z)and transformationψ(r,z)=r2f(z). Absolute residuals are used to check the efficiency and consistency of HAM. Other analytical techniques are compared with the present work. It is shown that results of good agreement can be obtained by choosing a suitable value of convergence control parameterhin the valid regionRh. The influence of different parameters on the flow is argued theoretically as well as graphically.
Impact of a Core Ferrule Design on Fracture Resistance of Teeth Restored with Cast Post and Core
Authors: Shamseddine Loubna , Chaaban Farid
Published: June 2016

Objectives. To investigate the influence of a contra bevel on the fracture resistance of teeth restored with cast post and core.Materials and Methods. Sixty plastic analogues of an upper incisor were endodontically treated and prepared with 6° internal taper and 2 mm of ferrule in order to receive a cast post and core. The prepared samples were divided into two groups (n=30); the first group serves as control while the second group was prepared with an external 30° bevel on the buccal and lingual walls. All samples crowned were exposed to a compressive load at 130° to their long axis until fractures occurred. Fracture resistance loads were recorded and failure modes were also observed. Mann-Whitney test was carried out to compare the two groups.Results. Mean failure loads for the groups were, respectively, 1038.69 N (SD ±243.52 N) and 1078.89 N (SD ±352.21 N). Statistically, there was no significant difference between the two groups (P=0.7675>0.05).Conclusion. In the presence of a ferrule and a crown in the anterior teeth, adding a secondary ferrule to the cast post and core will not increase the resistance to fracture.
The Dynamical Behaviors in a Stochastic SIS Epidemic Model with Nonlinear Incidence
Authors: Rifhat Ramziya , Ge Qing , Teng Zhidong
Published: June 2016

A stochastic SIS-type epidemic model with general nonlinear incidence and disease-induced mortality is investigated. It is proved that the dynamical behaviors of the model are determined by a certain threshold valueR~0. That is, whenR~0<1and together with an additional condition, the disease is extinct with probability one, and whenR~0>1, the disease is permanent in the mean in probability, and when there is not disease-related death, the disease oscillates stochastically about a positive number. Furthermore, whenR~0>1, the model admits positive recurrence and a unique stationary distribution. Particularly, the effects of the intensities of stochastic perturbation for the dynamical behaviors of the model are discussed in detail, and the dynamical behaviors for the stochastic SIS epidemic model with standard incidence are established. Finally, the numerical simulations are presented to illustrate the proposed open problems.
A Study on the Instantaneous Turbulent Flow Field in a 90-Degree Elbow Pipe with Circular Section
Authors: Wang Shiming , Ren Cheng , Sun Yangfei , Yang Xingtuan , Tu Jiyuan
Published: June 2016

Based on the special application of 90-degree elbow pipe in the HTR-PM, the large eddy simulation was selected to calculate the instantaneous flow field in the 90-degree elbow pipe combining with the experimental results. The characteristics of the instantaneous turbulent flow field under the influence of flow separation and secondary flow were studied by analyzing the instantaneous pressure information at specific monitoring points and the instantaneous velocity field on the cross section of the elbow. The pattern and the intensity of the Dean vortex and the small scale eddies change over time and induce the asymmetry of the flow field. The turbulent disturbance upstream and the flow separation near the intrados couple with the vortexes of various scales. Energy is transferred from large scale eddies to small scale eddies and dissipated by the viscous stress in the end.