bluuebunny/crossref_metadata_2025 huggingface dataset:
Effectiveness of Acupressure on Pruritus and Lichenification Associated with Atopic Dermatitis: A Pilot Trial
Authors: Lee Kachiu Cecilia , Keyes Ashley , Hensley Jennifer R , Gordon Jennifer R , Kwasny Mary J , West Dennis P , Lio Peter A
Published: December 2011

Background

Pruritus is a debilitating aspect of atopic dermatitis (AD). Acupuncture has been reported to diminish pruritus, but self-administered acupressure has not been previously evaluated.

Objectives

To evaluate the effectiveness of acupressure on the severity of eczema in a pilot trial.

Methods

Adult patients with AD were randomised to an intervention group (acupressure with standard of care) or a control group (standard of care alone). Subjects in the intervention group performed acupressure using a 1.2 mm acupellet at the LI11 point, applying pressure for 3 min three times per week for 4 weeks. The severity of itching and AD at baseline and at 4 weeks were measured on a visual analogue scale (VAS), the Investigator's Global Assessment (IGA) and the Eczema Area and Severity Index (EASI).

Results

Fifteen subjects were enrolled, 12 of whom completed the study between November 2009 and May 2011. There was no significant change between baseline and follow-up survey scores within the control group. In the investigation group there was a decrease in the VAS score (p=0.05) and EASI lichenification (p=0.03), although without significant change in the overall EASI score. Comparison of the scores between groups showed a greater decrease in VAS in the experimental group than in the control group (p=0.04), and a decrease in the IGA (p=0.03) and EASI lichenification score (p=0.03). The overall EASI scores were unchanged.

Conclusion

Subjects using acupressure at LI11 for 4 weeks had improvement in pruritus and lichenification. Acupressure may prove to be an easily administered alternative treatment, but larger-scale studies are needed to confirm these preliminary findings.
STUDY OF THE DIJET INVARIANT MASS IN W + JETS EVENTS BY THE DØ COLLABORATION
Authors: SEKARIC JADRANKA
Published: December 2011

The recent claim by the CDF Collaboration of a possible anomalous dijet resonance in their data required experimental verification from other hadron collider experiments. We present a study of the dijet invariant mass spectrum in events with two jets produced in association with a W→ℓν boson at the DØ experiment. We investigate the dijet mass range between 110 GeV /c2 and 170 GeV /c2 and find no evidence for any resonant dijet production.
Synthesis, circular dichroism, DNA cleavage and singlet oxygen photogeneration of 4-amidinophenyl porphyrins
Authors: Wang Kai , Poon Chun T. , Choi Chun Y. , Wong Wai-Kwok , Kwong Daniel W.J. , Yu Fa Q. , Zhang Heng , Li Zao Y.
Published: December 2011

5,10,15,20-tetrakis(4-amidinophenyl)porphyrin (Por 1), its Zn complex (Por 2) and its conjugate with a tetraphenylporphyrin to form a bisporphyrin (Por 3) were prepared. The monomeric Por 1 and Por 2 showed both intercalative and external binding with DNA whereas only external DNA binding was seen in the bisporphyrin, Por 3 by circular dichroism and UV-vis. The DNA photocleavage activities of these porphyrins followed the order: Por 1 ~ Por 2 > Por 3, which did not correlate with their measured 1O2 production rates. It suggests 4-amidinophenylporphyrins are promising new photodynamic therapeutic agents.
Synthesis, properties and near-infrared imaging evaluation of glucose conjugated zinc phthalocyanine via Click reaction
Authors: Lv Feng , He Xujun , Lu li , Wu Li , Liu Tianjun
Published: December 2011

In order to develop a novel near infrared fluorescence agent, glucose conjugated zinc phthalocyanine, [2,9(10),16(17),23(24)-tetrakis((1-(β-D-glucopyranose-2-yl)-1H-1,2,3-triazol-4-yl)methoxyl)phthalocyaninato]zinc(II), was synthesized via Click reaction. Their chemical structures were characterized by mass spectrometry, nuclear magnetic resonance spectrum. Their light stability and fluorescence quantum yield were evaluated by UV-visible and fluorescent spectroscopic method. Optical imaging in vivo was performed with this saccharide conjugated phthalocyanine as probe on liver tumor-bearing nude mice. Near-infrared imaging effect, organ aggregation as well as distribution of probe in vivo were evaluated by in vivo fluorescence imaging technique. Results show that glucose conjugated zinc phthalocyanine has favorable water solubility, good optical stability and high emission ability in near infrared region. Imaging results demonstrate that saccharide conjugated phthalocyanine has possess obvious imaging effect in vivo, which implies its potential in cancer diagnosis as near infrared optical probe.
HIGH ACCURACY ARITHMETIC AVERAGE TYPE DISCRETIZATION FOR THE SOLUTION OF TWO-SPACE DIMENSIONAL NONLINEAR WAVE EQUATIONS
Authors: MOHANTY R. K. , GOPAL VENU
Published: December 2011

In this paper, we propose a new high accuracy discretization based on the ideas given by Chawla and Shivakumar for the solution of two-space dimensional nonlinear hyperbolic partial differential equation of the form utt = A(x, y, t)uxx + B(x, y, t)uyy + g(x, y, t, u, ux, uy, ut), 0 < x, y < 1, t > 0 subject to appropriate initial and Dirichlet boundary conditions. We use only five evaluations of the function g and do not require any fictitious points to discretize the differential equation. The proposed method is directly applicable to wave equation in polar coordinates and when applied to a linear telegraphic hyperbolic equation is shown to be unconditionally stable. Numerical results are provided to illustrate the usefulness of the proposed method.
Managing data transfers in computer clusters with orchestra
Authors: Chowdhury Mosharaf , Zaharia Matei , Ma Justin , Jordan Michael I. , Stoica Ion
Published: December 2011

Cluster computing applications like MapReduce and Dryad transfer massive amounts of data between their computation stages. These transfers can have a significant impact on job performance, accounting for more than 50% of job completion times. Despite this impact, there has been relatively little work on optimizing the performance of these data transfers, with networking researchers traditionally focusing on per-flow traffic management. We address this limitation by proposing a global management architecture and a set of algorithms that (1) improve the transfer times of common communication patterns, such as broadcast and shuffle, and (2) allow scheduling policies at the transfer level, such as prioritizing a transfer over other transfers. Using a prototype implementation, we show that our solution improves broadcast completion times by up to 4.5X compared to the status quo in Hadoop. We also show that transfer-level scheduling can reduce the completion time of high-priority transfers by 1.7X.
How many tiers?
Authors: Valancius Vytautas , Lumezanu Cristian , Feamster Nick , Johari Ramesh , Vazirani Vijay V.
Published: December 2011

ISPs are increasingly selling "tiered" contracts, which offer Internet connectivity to wholesale customers in bundles, at rates based on the cost of the links that the traffic in the bundle is traversing. Although providers have already begun to implement and deploy tiered pricing contracts, little is known about how to structure them. While contracts that sell connectivity on finer granularities improve market efficiency, they are also more costly for ISPs to implement and more difficult for customers to understand. Our goal is to analyze whether current tiered pricing practices in the wholesale transit market yield optimal profits for ISPs and whether better bundling strategies might exist. In the process, we deliver two contributions: 1) we develop a novel way of mapping traffic and topology data to a demand and cost model, and 2) we fit this model on three large real-world networks: an European transit ISP, a content distribution network, and an academic research network, and run counterfactuals to evaluate the effects of different bundling strategies. Our results show that the common ISP practice of structuring tiered contracts according to the cost of carrying the traffic flows (
e.g.
, offering a discount for traffic that is local) can be suboptimal and that dividing contracts based on
both traffic demand and the cost of carrying it
into
only three or four tiers
yields near-optimal profit for the ISP.
The evolution of layered protocol stacks leads to an hourglass-shaped architecture
Authors: Akhshabi Saamer , Dovrolis Constantine
Published: December 2011

The Internet protocol stack has a layered architecture that resembles an hourglass. The lower and higher layers tend to see frequent innovations, while the protocols at the waist of the hourglass appear to be "ossified". We propose
EvoArch
, an abstract model for studying protocol stacks and their evolution.
EvoArch
is based on a few principles about layered network architectures and their evolution in a competitive environment where protocols acquire value based on their higher layer applications and compete with other protocols at the same layer.
EvoArch
produces an hourglass structure that is similar to the Internet architecture from general initial conditions and in a robust manner. It also suggests a plausible explanation why some protocols, such as TCP or IP, managed to survive much longer than most other protocols at the same layers. Furthermore, it suggests ways to design more competitive new protocols and more evolvable future Internet architectures.
Towards predictable datacenter networks
Authors: Ballani Hitesh , Costa Paolo , Karagiannis Thomas , Rowstron Ant
Published: December 2011

The shared nature of the network in today's multi-tenant datacenters implies that network performance for tenants can vary significantly. This applies to both production datacenters and cloud environments. Network performance variability hurts application performance which makes tenant costs unpredictable and causes provider revenue loss. Motivated by these factors, this paper makes the case for extending the tenant-provider interface to explicitly account for the network. We argue this can be achieved by providing tenants with a virtual network connecting their compute instances. To this effect, the key contribution of this paper is the design of virtual network abstractions that capture the trade-off between the performance guarantees offered to tenants, their costs and the provider revenue.

To illustrate the feasibility of virtual networks, we develop Oktopus, a system that implements the proposed abstractions. Using realistic, large-scale simulations and an Oktopus deployment on a 25-node two-tier testbed, we demonstrate that the use of virtual networks yields significantly better and more predictable tenant performance. Further, using a simple pricing model, we find that the our abstractions can reduce tenant costs by up to 74% while maintaining provider revenue neutrality.
Improving datacenter performance and robustness with multipath TCP
Authors: Raiciu Costin , Barre Sebastien , Pluntke Christopher , Greenhalgh Adam , Wischik Damon , Handley Mark
Published: December 2011

The latest large-scale data centers offer higher aggregate bandwidth and robustness by creating multiple paths in the core of the net- work. To utilize this bandwidth requires different flows take different paths, which poses a challenge. In short, a single-path transport seems ill-suited to such networks.

We propose using Multipath TCP as a replacement for TCP in such data centers, as it can effectively and seamlessly use available bandwidth, giving improved throughput and better fairness on many topologies. We investigate what causes these benefits, teasing apart the contribution of each of the mechanisms used by MPTCP.

Using MPTCP lets us rethink data center networks, with a different mindset as to the relationship between transport protocols, rout- ing and topology. MPTCP enables topologies that single path TCP cannot utilize. As a proof-of-concept, we present a dual-homed variant of the FatTree topology. With MPTCP, this outperforms FatTree for a wide range of workloads, but costs the same.

In existing data centers, MPTCP is readily deployable leveraging widely deployed technologies such as ECMP. We have run MPTCP on Amazon EC2 and found that it outperforms TCP by a factor of three when there is path diversity. But the biggest benefits will come when data centers are designed for multipath transports.
Insomnia in the access
Authors: Goma Eduard , Canini Marco , Lopez Toledo Alberto , Laoutaris Nikolaos , Kostić Dejan , Rodriguez Pablo , Stanojević Rade , Yagüe Valentin Pablo
Published: December 2011

Access networks include modems, home gateways, and DSL Access Multiplexers (DSLAMs), and are responsible for 70-80% of total network-based energy consumption. In this paper, we take an in-depth look at the problem of greening access networks, identify root problems, and propose practical solutions for their user- and ISP-parts. On the user side, the combination of
continuous light traffic
and
lack of alternative paths
condemns gateways to being powered most of the time despite having Sleep-on-Idle (SoI) capabilities. To address this, we introduce Broadband Hitch-Hiking (BH
2
), that takes advantage of the overlap of wireless networks to aggregate user traffic in as few gateways as possible. In current urban settings BH
2
can power off 65-90% of gateways. Powering off gateways permits the remaining ones to synchronize at higher speeds due to reduced crosstalk from having fewer active lines. Our tests reveal speedup up to 25%. On the ISP side, we propose introducing simple inexpensive switches at the distribution frame for batching active lines to a subset of cards letting the remaining ones sleep. Overall, our results show an 80% energy savings margin in access networks. The combination of B
2
and switching gets close to this margin, saving 66% on average.
Understanding the impact of video quality on user engagement
Authors: Dobrian Florin , Sekar Vyas , Awan Asad , Stoica Ion , Joseph Dilip , Ganjam Aditya , Zhan Jibin , Zhang Hui
Published: December 2011

As the distribution of the video over the Internet becomes main- stream and its consumption moves from the computer to the TV screen, user expectation for high quality is constantly increasing. In this context, it is crucial for content providers to understand if and how video quality affects user engagement and how to best invest their resources to optimize video quality. This paper is a first step towards addressing these questions. We use a unique dataset that spans different content types, including short video on demand (VoD), long VoD, and live content from popular video con- tent providers. Using client-side instrumentation, we measure quality metrics such as the join time, buffering ratio, average bitrate, rendering quality, and rate of buffering events.

We quantify user engagement both at a per-video (or view) level and a per-user (or viewer) level. In particular, we find that the percentage of time spent in buffering (buffering ratio) has the largest impact on the user engagement across all types of content. However, the magnitude of this impact depends on the content type, with live content being the most impacted. For example, a 1% increase in buffering ratio can reduce user engagement by more than three minutes for a 90-minute live video event. We also see that the average bitrate plays a significantly more important role in the case of live content than VoD content.
An untold story of middleboxes in cellular networks
Authors: Wang Zhaoguang , Qian Zhiyun , Xu Qiang , Mao Zhuoqing , Zhang Ming
Published: December 2011

The use of cellular data networks is increasingly popular as network coverage becomes more ubiquitous and many diverse user-contributed mobile applications become available. The growing cellular traffic demand means that cellular network carriers are facing greater challenges to provide users with good network performance and energy efficiency, while protecting networks from potential attacks. To better utilize their limited network resources while securing the network and protecting client devices the carriers have already deployed various network policies that influence traffic behavior. Today, these policies are mostly opaque, though they directly impact application designs and may even introduce network vulnerabilities.

We present
NetPiculet
, the first tool that unveils carriers' NAT and firewall policies by conducting intelligent measurement. By running
NetPiculet
on the major U.S. cellular providers as well as deploying it as a smartphone application in the wild covering more than 100 cellular ISPs, we identified the key NAT and firewall policies which have direct implications on performance, energy, and security. For example, NAT boxes and firewalls set timeouts for idle TCP connections, which sometimes cause significant energy waste on mobile devices. Although most carriers today deploy sophisticated firewalls, they are still vulnerable to various attacks such as battery draining and denial of service. These findings can inform developers in optimizing the interaction between mobile applications and cellular networks and also guide carriers in improving their network configurations.
Towards a fully distributed n-tuple store
Authors: Shvartzshnaider Yan , Ott Maximilian
Published: December 2011

We present our work towards building a novel distributed n-tuple store by extending the Kademlia DHT [1] algorithm to support n dimensional keys as well as an multi get operator, where some of the dimensions of the "query" key can be left unspecified.
"Roto-Rooting" your router
Authors: Chasaki Danai
Published: December 2011

Our work presents the first practical example of an entirely new class of network attacks - attacks that target the network infrastructure. Modern routers use general purpose programmable processors, and the software used for packet processing on these systems is potentially vulnerable to remote exploits. We describe a specific attack that can launch a devastating denial-of-service attack by sending just a single packet. We also show that there are effective defense techniques, based on processor monitoring, that can help in detecting and avoiding such attacks.
Covert channels in multiple access protocols
Authors: Ahmadzadeh Seyed Ali , Agnew Gordon
Published: December 2011

In this paper, the use of structural behavior of communication protocols in designing new covert channels is investigated. In this way, a new covert transmitter is designed based on a modified CSMA protocol that enables the transmitter to embed a covert message in its overt traffic. The proposed scheme provides high covert rate without compromising the stealthiness of the channel.
Minimising cell transmit power
Authors: López-Pérez David , Chu Xiaoli , Vasilakos Athanasios V. , Claussen Holger
Published: December 2011

With the introduction of femtocells, cellular networks are moving from the conventional centralised architecture to a distributed one, where each network cell should make its own radio resource management decisions, while providing inter-cell interference mitigation. However, realising this distributed cellular network architecture is not a trivial task. In this paper, we first introduce a simple self-organisation rule under which a distributed cellular network is able to converge into an efficient resource allocation pattern, then propose a novel resource allocation model taking realistic resource allocation constraints into account, and finally evaluate the performance of the proposed self-organisation rule and resource allocation model using system-level simulations.
Building virtual networks across multiple domains
Authors: Werle Christoph , Papadimitriou Panagiotis , Houidi Ines , Louati Wajdi , Zeghlache Djamal , Bless Roland , Mathy Laurent
Published: December 2011

This paper presents a platform for virtual network (VN) provisioning across multiple domains. The platform decomposes VN provisioning into multiple steps to address the implications of limited information disclosure on resource discovery and allocation. A new VN embedding algorithm with simultaneous node and link mapping allows to assign resources within each domain. For inter-domain virtual link setup, we design and realize a signaling protocol that also integrates resource reservations for providing virtual links with Quality-of-Service guarantees. Experimental results show that small VNs can be provisioned within a few seconds.
Multi-relational social networks in a large-scale MMORPG
Authors: Son Seokshin , Kang Ah Reum , Kim Hyun-chul , Kwon Ted Taekyoung , Park Juyong , Kim Huy Kang
Published: December 2011

We analyze multi-relational social interaction networks in a large-scale commercial Massively Multiplayer Online Role-Playing Game(MMORPG). Our work is based on data from AION, currently the world's second most-played MMORPG with 3.4 million subscribers as of mid 2010, created and serviced by NCSoft, Inc. We construct and characterize six distinct interactivity networks (Friend, Private Messaging, Party invitation, Trade, Mail, and Shop), each representing diverse player interaction types.
netmap
Authors: Rizzo Luigi , Landi Matteo
Published: December 2011

Recent papers have shown that wire-speed packet processing is feasible in software even at 10~Gbit/s, but the result has been achieved taking direct control of the network controllers to cut down OS and device driver overheads.

In this paper we show how to achieve similar performance in safer conditions on standard operating systems. As in some other proposals, our framework, called netmap, maps packet buffers into the process' memory space; but unlike other proposals, any operation that may affect the state of the hardware is filtered by the OS. This protects the system from crashes induced by misbehaving programs, and simplifies the use of the API.

Our tests show that netmap takes as little as 90 clock cycles to move one packet between the wire and the application, almost one order of magnitude less than using the standard OS path. A single core at 1.33~GHz can send or receive packets at wire speed on 10~Gbit/s links (14.8~Mpps), with very good scalability in the number of cores and clock speed.

At least three factors contribute to this performance: i) no overhead for encapsulation and metadata management; ii) no per-packet system calls and data copying (ioctl()s are still required, but involve no copying and their cost is amortized over a batch of packets); iii) much simpler device driver operation, because buffers have a plain and simple format that requires
Performance based traffic control with IDIPS
Authors: Saucez Damien , Bonaventure Olivier
Published: December 2011

Nowadays Internet is ubiquitous resulting in an increasing path diversity and content duplication. However, while content can be retrieved from many different places, the paths to those places are not equivalent. Indeed, some paths offer better bandwidth while others are less expensive or more stable. In addition, a new range of applications is sensitive to the performance of the paths that carry their traffic. To support this evolution of the Internet, we propose ISP-Driven Informed Path Selection (IDIPS). Any ISP can easily deploy IDIPS to help its customers to select the paths that best meet their requirements in order to reach their content. IDIPS helps in this selection through pro-active measurements and ISP-defined policies. IDIPS is scalable and can support thousands of clients. IDIPS is also flexible and can thus be used by the ISP to optimize its routing decisions to take the performance of its inter-domain links into account.
Implementing ARP-path low latency bridges in NetFPGA
Authors: Rojas Elisa , Naous Jad , Ibañez Guillermo , Rivera Diego , Carral Juan A. , Arco Jose M.
Published: December 2011

The demo is focused on the implementation of ARP-Path (a.k.a. FastPath) bridges, a recently proposed concept for low latency bridges. ARP-Path Bridges rely on the race between broadcast ARP Request packets, to discover the minimum latency path to the destination host. Several implementations (in Omnet++, Linux, OpenFlow, NetFPGA) have shown that ARP-Path exhibits loop-freedom, does not block links, is fully transparent to hosts and neither needs a spanning tree protocol to prevent loops nor a link state protocol to obtain low latency paths. This demo compares our hardware implementation on NetFPGA to bridges running STP, showing that ARP-Path finds lower latency paths than STP.
A protocol for disaster data evacuation
Authors: Rabl Tilmann , Stegmaier Florian , Döller Mario , Vang The Thong
Published: December 2011

Data is the basis of the modern information society. However, recent natural catastrophes have shown that it is not possible to definitively secure a data storage location. Even if the storage location is not destroyed itself the access may quickly become impossible, due to the breakdown of connections or power supply. However, this rarely happens without any warning. While floods have hours or days of warning time, tsunamis usually leave only minutes for reaction and for earthquakes there are only seconds. In such situations, timely evacuation of important data is the key challenge. Consequently, the focus lies on minimizing the time to move away all data from the storage location whereas the actual time to arrival remains less (but still) important. This demonstration presents the dynamic fast send protocol (DFSP), a new bulk data transfer protocol. It employs striping to dynamic intermediate nodes in order to minimize sending time and to utilize the sender's resources to a high extent.
MPLS-TE and MPLS VPNS with openflow
Authors: Sharafat Ali Reza , Das Saurav , Parulkar Guru , McKeown Nick
Published: December 2011

We demonstrate MPLS Traffic Engineering (MPLS-TE) and MPLS-based Virtual Private Networks (MPLS VPNs) using OpenFlow [1] and NOX [6]. The demonstration is the outcome of an engineering experiment to answer the following questions: How hard is it to implement a complex control plane on top of a network controller such as NOX? Does the global vantage point in NOX make the implementation easier than the traditional method of implementing it on every switch, embedded in the data plane? We implemented every major feature of MPLS-TE and MPLS-VPN in just 2,000 lines of code, compared to much larger lines of code in the more traditional approach, such as Quagga-MPLS. Because NOX maintains a consistent, up-to-date topology map, the MPLS control plane features are quite simple to implement. And its simplicity makes it easy to extend: We have easily added several new features; something a network operator could do to customize their network to meet their customers' needs.

The demo consists of two parts: MPLS-TE services and then MPLS VPN driven by a GUI.
Cyber-physical handshake
Authors: Wu Fang-Jing , Chu Feng-I , Tseng Yu-Chee
Published: December 2011

While sensor-enabled devices have greatly enriched human interactions in our daily life, discovering the essential knowledge behind sensing data is a critical issue to connect the cyber world and the physical world. This motivates us to design an innovative sensor-aided social network system, termed cyber-physical handshake. It allows two users to naturally exchange personal information with each other after detecting and authenticating the handshaking patterns between them. This work describes our design of detection and authentication mechanisms to achieve this purpose and our prototype system to facilitate handshake social behavior.
Separating ownership topology and encapsulation with generic universe types
Authors: Dietl Werner , Drossopoulou Sophia , Müller Peter
Published: December 2011

Ownership is a powerful concept to structure the object store and to control aliasing and modifications of objects. This article presents an ownership type system for a Java-like programming language with generic types.

Like our earlier Universe type system, Generic Universe Types structure the heap hierarchically. In contrast to earlier work, we separate the enforcement of an ownership topology from an encapsulation system. The topological system uses an existential modifier to express that no ownership information is available statically. On top of the topological system, we build an encapsulation system that enforces the owner-as-modifier discipline. This discipline does not restrict aliasing, but requires modifications of an object to be initiated by its owner. This allows owner objects to control state changes of owned objects—for instance, to maintain invariants. Separating the topological system from the encapsulation system allows for a cleaner formalization, separation of concerns, and simpler reuse of the individual systems in different contexts.
Revamping storage performance
Authors: Anthes Gary
Published: December 2011

Great strides are being made in finding fast alternatives to the slow disks that dominate storage systems, but fast media are not nearly enough.
Analyzing Apple products
Authors: Wright Alex
Published: December 2011

Researchers untangle the complex web of Apple's global supply chain---and offer lessons for managers and policymakers trying to chart the future course of U.S. industry.
John McCarthy, 1927--2011
Authors: Hyman Paul
Published: December 2011

Winner of the 1971 A.M. Turing Award, John McCarthy was a founder of artificial intelligence and inventor of the Lisp programming language.
The yin and yang of copyright and technology
Authors: Picker Randal C.
Published: December 2011

Examining the recurring conflicts between copyright and technology from piano rolls to domain-name filtering.
Flexible experimentation in wireless sensor networks
Authors: Coulson Geoff , Porter Barry , Chatzigiannakis Ioannis , Koninis Christos , Fischer Stefan , Pfisterer Dennis , Bimschas Daniel , Braun Torsten , Hurni Philipp , Anwander Markus , Wagenknecht Gerald , Fekete Sándor P. , Kröller Alexander , Baumgartner Tobias
Published: December 2011

Virtual testbeds model them by seamlessly integrating physical, simulated, and emulated sensor nodes and radios in real time.
(Computer) vision without sight
Authors: Manduchi Roberto , Coughlan James
Published: December 2011

Computer vision holds the key for the blind or visually impaired to explore the visual world.
Significance of para-esophageal lymph nodes in food or aeroallergen-induced iNKT cell-mediated experimental eosinophilic esophagitis
Authors: Rajavelu Priya , Rayapudi Madhavi , Moffitt Matthew , Mishra Akanksha , Mishra Anil
Published: December 2011

Eosinophilic esophagitis (EoE) is a recently recognized inflammatory disorder driven by food hypersensitivity; however, the specific foods and mechanisms involved are unclear. In patients with EoE, we have found that hypersensitivities to corn and peanuts are the most common. Accordingly, we sensitized and exposed mice either intranasally or intragastrically with corn or peanut extract or saline. Esophageal eosinophilia, the genes of eosinophil-directed cytokines, and allergen-induced antibodies were examined in mice challenged with corn or peanut extract or saline. A high number of esophageal lamina propria eosinophils as well as eosinophilic microabscesses, intraepithelial eosinophils, extracellular eosinophilic granules, thickened and disrupted epithelial mucosa, and mast cell hyperplasia were observed in the esophagus of peanut or corn allergen-challenged mice. Mechanistic analysis indicated that para-esophageal lymph nodes might be critical in the trafficking of eosinophils to the esophagus and in EoE association to airway eosinophilia. Furthermore, experimentation with gene-targeted mice revealed that peanut allergen-induced EoE was dependent on eotaxin and invariant natural killer T (iNKT) cells, as CD1d and eotaxin-1/2 gene-deficient mice were protected from disease induction. Thus we provide evidence that para-esophageal lymph nodes are involved in food- or aeroallergen-induced eosinophilia and patchy EoE pathogenesis, likely a mechanism dependent on eotaxins and iNKT cells.
Respiratory mechanics during high-frequency oscillatory ventilation: a physical model and preterm infant study
Authors: Singh Rachana , Courtney Sherry E. , Weisner Michael D. , Habib Robert H.
Published: December 2011

Accurate mechanics measurements during high-frequency oscillatory ventilation (HFOV) facilitate optimizing ventilator support settings. Yet, these are influenced substantially by endotracheal tube (ETT) contributions, which may dominate when leaks around uncuffed ETT are present. We hypothesized that 1) the effective removal of ETT leaks may be confirmed via direct comparison of measured vs. model-predicted mean intratracheal pressure [mPtr (meas) vs. mPtr (pred)], and 2) reproducible respiratory system resistance (Rrs) and compliance (Crs) may be derived from no-leak oscillatory Ptr and proximal flow. With the use of ETT test-lung models, proximal airway opening (Pao) and distal (Ptr) pressures and flows were measured during slow-cuff inflations until leaks are removed. These were repeated for combinations of HFOV settings [frequency, mean airway pressure (Paw), oscillation amplitudes (ΔP), and inspiratory time (%tI)] and varying test-lung Crs. Results showed that leaks around the ETT will 1) systematically reduce the effective distending pressures and lung-delivered oscillatory volumes, and 2) derived mechanical properties are increasingly nonphysiologic as leaks worsen. Mean pressures were systematically reduced along the ventilator circuit and ETT (Paw > Pao > Ptr), even for no-leak conditions. ETT size-specific regression models were then derived for predicting mPtr based on mean Pao (mPao), ΔP, %tI, and frequency. Next, in 10 of 11 studied preterm infants (0.77 ± 0.24 kg), no-to-minimal leak was confirmed based on excellent agreement between mPtr (meas) and mPtr (pred), and consequently, their oscillatory respiratory mechanics were evaluated. Infant resistance at the proximal ETT (RETT; resistance airway opening = RETT + Rrs; P < 0.001) and ETT inertance ( P = 0.014) increased significantly with increasing ΔP (50%, 100%, and 150% baseline), whereas Rrs showed a modest, nonsignificant increase ( P = 0.14), and Crs was essentially unchanged ( P = 0.39). We conclude that verifying no-leak conditions is feasible by comparison of model-derived vs. distending mPtr (meas). This facilitated the reliable and accurate assessment of physiologic respiratory mechanical properties that can objectively guide ventilatory management of HFOV-treated preterm infants.
X-ray powder diffraction data for two new compounds (NH4)1.5Ni2V2O7(OH)1.5 · H2O and (NH4)1.5Cu1.125Ni1.125V2O7(OH)2 · H2O
Authors: Arboleda Johana , Echavarría Adriana
Published: December 2011

Two new bimetallic and trimetallic compounds (NH4)1.5Ni2V2O7(OH)1.5 · H2O and (NH4)1.5Cu1.125 Ni1.125V2O7(OH)2 · H2O were synthesized by hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and X-Ray fluorescence (XRF). Crystallographic studies showed that both compounds are hexagonal with space group P-62c.
Rigid body refinements in GSAS/EXPGUI
Authors: Lake Charles H. , Toby Brian H.
Published: December 2011

Rigid bodies provide a way to simplify the model used in a crystallographic refinement by removing parameters that describe degrees of freedom that are unlikely to change based on chemical experience. The GSAS software package provides a powerful implementation of rigid bodies that allows for refinement of classes of bond lengths, grouping of bodies to further reduce parameterization and where atomic motion can be described from group displacement parameters (TLS) representation. However, use of rigid bodies in GSAS is complex to learn and time-consuming to perform. This paper describes how the rigid body definition process has been simplified and extended through implementation in the EXPGUI interface to GSAS.
Automated parametric Rietveld refinement: Applications in reaction kinetics and in the extraction of microstructural information
Authors: Rajiv P. , Dinnebier R. E. , Jansen M. , Joswig M.
Published: December 2011

Two applications of parametric Rietveld refinement employing a newly developed robust computer program are presented. The first application focuses on the parametric kinetic analysis of the reactions involving phase transitions of various polymorphic forms of copper phthalocyanine pigments. The second application concerns the parameterization of crystallite size with respect to experimental temperature. XRPD data for nanocrystalline titanium dioxide measured in dependence on temperature are used in this case study. Both the applications were realized with the help of the developed program in combination with the launch mode of topas® software.
ATM Mutations in Patients with Hereditary Pancreatic Cancer
Authors: Roberts Nicholas J. , Jiao Yuchen , Yu Jun , Kopelovich Levy , Petersen Gloria M. , Bondy Melissa L. , Gallinger Steven , Schwartz Ann G. , Syngal Sapna , Cote Michele L. , Axilbund Jennifer , Schulick Richard , Ali Syed Z. , Eshleman James R. , Velculescu Victor E. , Goggins Michael , Vogelstein Bert , Papadopoulos Nickolas , Hruban Ralph H. , Kinzler Kenneth W. , Klein Alison P.
Published: December 2011

Pancreatic cancers are the fourth most-common cause of cancer-related deaths in the Western world, with >200,000 cases reported in 2010. Although up to 10% of these cases occur in familial patterns, the hereditary basis for predisposition in the vast majority of affected families is unknown. We used next-generation sequencing, including whole-genome and whole-exome analyses, and identified heterozygous, constitutional, ataxia telangiectasia mutated (ATM) gene mutations in 2 kindreds with familial pancreatic cancer. Mutations segregated with disease in both kindreds and tumor analysis demonstrated LOH of the wild-type allele. By using sequence analysis of an additional 166 familial pancreatic cancer probands, we identified 4 additional patients with deleterious mutations in the ATM gene, whereas we identified no deleterious mutations in 190 spouse controls (P = 0.046). When we considered only the mostly severely affected families with 3 or more pancreatic cancer cases, 4 deleterious mutations were found in 87 families (P = 0.009). Our results indicate that inherited ATM mutations play an important role in familial pancreatic cancer predisposition.

Significance: The genes responsible for the majority of cases of familial pancreatic ductal adenocarcinoma are unknown. We here identify ATM as a predisposition gene for pancreatic ductal adenocarcinoma. Our results have important implications for the management of patients in affected families and illustrate the power of genome-wide sequencing to identify the basis of familial cancer syndromes. Cancer Discovery; 2(1): 41–6. ©2011 AACR.

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Essential Gene Profiles in Breast, Pancreatic, and Ovarian Cancer Cells
Authors: Marcotte Richard , Brown Kevin R. , Suarez Fernando , Sayad Azin , Karamboulas Konstantina , Krzyzanowski Paul M. , Sircoulomb Fabrice , Medrano Mauricio , Fedyshyn Yaroslav , Koh Judice L.Y. , van Dyk Dewald , Fedyshyn Bohdana , Luhova Marianna , Brito Glauber C. , Vizeacoumar Franco J. , Vizeacoumar Frederick S. , Datti Alessandro , Kasimer Dahlia , Buzina Alla , Mero Patricia , Misquitta Christine , Normand Josee , Haider Maliha , Ketela Troy , Wrana Jeffrey L. , Rottapel Robert , Neel Benjamin G. , Moffat Jason
Published: December 2011

Genomic analyses are yielding a host of new information on the multiple genetic abnormalities associated with specific types of cancer. A comprehensive description of cancer-associated genetic abnormalities can improve our ability to classify tumors into clinically relevant subgroups and, on occasion, identify mutant genes that drive the cancer phenotype (“drivers”). More often, though, the functional significance of cancer-associated mutations is difficult to discern. Genome-wide pooled short hairpin RNA (shRNA) screens enable global identification of the genes essential for cancer cell survival and proliferation, providing a “functional genomic” map of human cancer to complement genomic studies. Using a lentiviral shRNA library targeting ∼16,000 genes and a newly developed, dynamic scoring approach, we identified essential gene profiles in 72 breast, pancreatic, and ovarian cancer cell lines. Integrating our results with current and future genomic data should facilitate the systematic identification of drivers, unanticipated synthetic lethal relationships, and functional vulnerabilities of these tumor types.

Significance: This study presents a resource of genome-scale, pooled shRNA screens for 72 breast, pancreatic, and ovarian cancer cell lines that will serve as a functional complement to genomics data, facilitate construction of essential gene profiles, help uncover synthetic lethal relationships, and identify uncharacterized genetic vulnerabilities in these tumor types. Cancer Discovery; 2(2); 172–89. © 2011 AACR.

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A Generalized Sequential Bonferroni Procedure Using Smoothed Weights for Genome-Wide Association Studies Incorporating Information on Hardy-Weinberg Disequilibrium among Cases
Authors: Gao Guimin , Kang Guolian , Wang Jiexun , Chen Wenan , Qin Huaizen , Jiang Bo , Li Qizhai , Sun Chuanyu , Liu Nianjun , Archer Kellie J. , Allison David B.
Published: December 2011

Background/Objectives: For genome-wide association studies (GWAS) with case-control designs, one of the most widely used association tests is the Cochran-Armitage (CA) trend test assuming an additive mode of inheritance. The CA trend test often has higher power than other association tests under additive and multiplicative disease models. However, it can have very low power under a recessive disease model in GWAS. Although tests (such as MAX3) robust to different genetic models have been developed, they often have relatively lower power than the CA trend test under additive and multiplicative models. The goal of this study is to propose an efficient method that not only has higher power than the CA trend test under dominant and recessive models but also maintains the power of the CA trend test under additive and multiplicative models. Methods: We employed the generalized sequential Bonferroni (GSB) procedure of Holm to incorporate information from a Hardy-Weinberg disequilibrium (HWD) test into the CA trend test based on estimating weights from the p values of the HWD test. We proposed to smooth the weights to reduce possible noise. Results and Conclusions: Results from extensive simulation studies showed that the proposed GSB procedure can achieve the goal described above.
Early Closure of Ileostomy Is Associated with Less Postoperative Nausea and Vomiting
Authors: Worni Mathias , Witschi André , Gloor Beat , Candinas Daniel , Laffer Urban T. , Kuehni Claudia E.
Published: December 2011

Background/Aims: Temporary loop ileostomy is increasingly used in colorectal surgery but necessitates secondary closure. We evaluated postoperative complications, particularly nausea and vomiting, in patients with early, intermediate, or late elective ileostomy closure. Methods: We included all patients undergoing ileostomy closure from 2001 to 2008. Time from ileostomy construction to closure was classified as early (EC, <12 weeks), intermediate (IC, 12–18 weeks), and late (LC, >18 weeks). Using multivariable logistic regression, we compared the frequency of postoperative complications between the groups. Results: We included 134 patients (87 males; median age 71 years, range 29–91). Carcinoma of the rectum (n = 67, 50%) was the main reason for ileostomy construction. The median time to ileostomy closure was 103 days (range 8–461). Among patients with EC, IC, and LC, postoperative nausea occurred in 50.0, 73.1, and 78.6%, respectively (p = 0.006), and postoperative vomiting in 22.5, 57.7, and 59.5%, respectively (p = 0.001). Adjusting for important covariates, the odds ratio for postoperative nausea was 2.0 (95% CI 0.76–5.1) for IC and 4.1 (95% CI 1.2–14.3) for LC compared to EC (p = 0.069). For postoperative vomiting, adjusted odds ratios were 3.8 (95% CI 1.4–10.4) for IC and 4.6 (95% CI 1.4–15.5) for LC (p = 0.012). Other complications did not differ between the groups. Conclusions: These findings suggest that early ileostomy closure might reduce postoperative nausea and vomiting.
Balancing the Risks and Benefits of Genomic Data Sharing: Genome Research Participants’ Perspectives
Authors: Oliver J.M. , Slashinski M.J. , Wang T. , Kelly P.A. , Hilsenbeck S.G. , McGuire A.L.
Published: December 2011

Background: Technological advancements are rapidly propelling the field of genome research forward, while lawmakers attempt to keep apace with the risks these advances bear. Balancing normative concerns of maximizing data utility and protecting human subjects, whose privacy is at risk due to the identifiability of DNA data, are central to policy decisions. Research on genome research participants making real-time data sharing decisions is limited; yet, these perspectives could provide critical information to ongoing deliberations. Methods: We conducted a randomized trial of 3 consent types affording varying levels of control over data release decisions. After debriefing participants about the randomization process, we invited them to a follow-up interview to assess their attitudes toward genetic research, privacy and data sharing. Results: Participants were more restrictive in their reported data sharing preferences than in their actual data sharing decisions. They saw both benefits and risks associated with sharing their genomic data, but risks were seen as less concrete or happening in the future, and were largely outweighed by purported benefits. Conclusion: Policymakers must respect that participants’ assessment of the risks and benefits of data sharing and their privacy-utility determinations, which are associated with their final data release decisions, vary. In order to advance the ethical conduct of genome research, proposed policy changes should carefully consider these stakeholder perspectives.
Have We Enough Glutamine and How Does It Work? A Clinician’s View
Authors: Soeters P.B. , Grecu I.
Published: December 2011

There is a gap between the scientific basis of the claim that in several disease states glutamine is lacking and the widespread belief that supplementation of glutamine to the nutritional regimen is beneficial in severely ill patients. Glutamine shortage exists when consuming tissues, playing a crucial role in the response to trauma and disease, receive insufficient amounts of glutamine. In these tissues (immune system, wound), glutamine is only partly oxidized but has more specific roles as nontoxic nitrogen carrier, precursor of several crucial metabolites required for cell proliferation and for maintenance of the redox potential, and as osmolyte. In inflammatory states, glutamine concentrations in plasma and tissues are decreased due to many disease-related factors, precluding its use as a reliable indicator of shortage. Isotope studies have yielded equivocal results, precluding their use as a reliable indicator of glutamine shortage or adequacy. The increase in the net release of glutamine from peripheral tissues to central tissues (immune system, liver, spleen, wound) in inflammatory states provides a better basis for the necessity to supplement the organism with extra glutamine in these conditions. Glutamine supplementation was beneficial in a few studies in burn or trauma patients. The clinical benefit of parenteral glutamine supplementation in patients with severe inflammation has been demonstrated more convincingly. The amounts of glutamine supplemented approximate the amounts released by peripheral tissues and utilized by central organs operative in host defense and are therefore in the physiological range.