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The assumptions we make about a dialogue partner's knowledge and communicative ability (i.e. our partner models) can influence our language choices. Although similar processes may operate in human-machine dialogue, the role of design in shaping these models, and their subsequent effects on interaction are not clearly understood. Focusing on synthesis design, we conduct a referential communication experiment to identify the impact of accented speech on lexical choice. In particular, we focus on whether accented speech may encourage the use of lexical alternatives that are relevant to a partner's accent, and how this is may vary when in dialogue with a human or machine. We find that people are more likely to use American English terms when speaking with a US accented partner than an Irish accented partner in both human and machine conditions. This lends support to the proposal that synthesis design can influence partner perception of lexical knowledge, which in turn guide user's lexical choices. We discuss the findings with relation to the nature and dynamics of partner models in human machine dialogue., In press, accepted at 1st International Conference on Conversational User Interfaces (CUI 2019)

The use of speech as an interaction modality has grown considerably through the integration of Intelligent Personal Assistants (IPAs- e.g. Siri, Google Assistant) into smartphones and voice based devices (e.g. Amazon Echo). However, there remain significant gaps in using theoretical frameworks to understand user behaviours and choices and how they may applied to specific speech interface interactions. This part-day multidisciplinary workshop aims to critically map out and evaluate theoretical frameworks and methodological approaches across a number of disciplines and establish directions for new paradigms in understanding speech interface user behaviour. In doing so, we will bring together participants from HCI and other speech related domains to establish a cohesive, diverse and collaborative community of researchers from academia and industry with interest in exploring theoretical and methodological issues in the field.

Ethanol alters BK (slo1) channel function leading to perturbation of physiology and behavior. Site(s) and mechanism(s) of ethanol-BK channel interaction are unknown. We demonstrate that ethanol docks onto a water-accessible site that is strategically positioned between the slo1 calcium-sensors and gate. Ethanol only accesses this site in presence of calcium, the BK channel's physiological agonist. Within the site, ethanol hydrogen-bonds with K361. Moreover, substitutions that hamper hydrogen bond formation or prevent ethanol from accessing K361 abolish alcohol action without altering basal channel function. Alcohol interacting site dimensions are approximately 10.7 × 8.6 × 7.1 Å, accommodating effective (ethanol-heptanol) but not ineffective (octanol, nonanol) channel activators. This study presents: (i) to our knowledge, the first identification and characterization of an n-alkanol recognition site in a member of the voltage-gated TM6 channel superfamily; (ii) structural insights on ethanol allosteric interactions with ligand-gated ion channels; and (iii) a first step for designing agents that antagonize BK channel-mediated alcohol actions without perturbing basal channel function.

Acinetobacter baumannii is increasingly recognized as an important multidrug-resistant nosocomial pathogen. Recent work has highlighted enhanced growth and heightened virulence in the presence of ethyl alcohols. As alcohol-based hand rubs (ABHRs) are extensively used in health care settings, the authors set out to determine whether the hand rubs could also influence the growth of prevalent multidrug-resistant strains circulating in UK hospitals. A significant increase in growth was observed when minimal media were supplemented with concentrations of 1 % and lower of four commercially available hand rubs. In addition, growth in ABHR-supplemented media resulted in secretion of proteins into the culture supernatant. One of these was identified as OmpA, which is recognized as having emulsifying activity, which could potentially confer enhanced pathogenicity to A. baumannii.

There had been significant research on background mosaic or sprite generation in the past. In some application domains such as surveillance, the complete view of an object might be of interest rather than the background scene. In this paper, we present object mosaicking for reconstruction of a moving object from its partial views due to limited view or object occlusion. Object mosaicking may play important role in identification and tracking of objects and face recognition. Our algorithm has three steps: automatic rectangular boundary detection, elimination of static temporal texture, and application of mosaic generation algorithms with varying blending methods. We have applied our object mosaicking on three sets of video objects and obtained promising results for object mosaicking.

We describe the design and implementation of Cells, a novel multi-tenanted virtual infrastructure service. Cells has the unique property of being self-hosting: it operates its own management system within one of the tenant virtual infrastructures that it manages and therefore benefits from the same security, flexibility and scalability as other tenant services. Cells is also differentiated by its declarative interface for infrastructure configuration, and its fine-grained control of network and storage connections within and between tenant infrastructures.

We present a novel LAN that has been designed to meet three criteria: it should be low cost, support standard protocols, and provide high performance. The LAN interconnects many workstations in a ring topology with a link rate of 1 Gbit/s. The packet format is the same as that of a B-ISDN cell except that our packets can have arbitrary length. The network also provides hardware support for ATM Adaptation Layer 5 as weIl as TCP/IP.We have implemented the ring network and we describe a network interface card which provides hardware support for critical functions such as calculating checksums. This card is used in conjunction with a second card that supports a single-copy implementation of the TCP/IP protocols. The application-to-application throughput has been measured at rates in excess of 200 Mbit/s between two workstations.

In this paper, we describe an architecture for high-speed storage nodes intended for supporting cloud-based storage I/O intensive applications such as file servers, backup servers and databases. The nodes can host multiple virtual machines each having direct access to a storage array via Single Route I/O Virtualization (SR-IOV). This is done in a way which does not compromise security. We demonstrate that SR-IOV imposes negligible overhead for storage I/O and provides the hosted virtual machines with four times the storage I/O bandwidth than is available from the same hardware when I/O is redirected through the hyper visor. We describe how the storage nodes are incorporated into a heterogeneous Infrastructure as a Service (IaaS) consisting of mixed storage and compute nodes.

Many current implementations of protocols such as the Transmission Control Protocol/Internet Protocol (TCP/IP) are inefficient because data are often accessed more frequently than necessary. Three techniques that reduce the need for memory bandwidth are proposed. The techniques are copy-on-write, page remapping, and single-copy. Afterburner, a network-independent card that provides the services that are necessary for a single-copy protocol stack, is described. The card has 1 MByte of local buffers and provides a simple interface to a variety of network link adapters, including HIPPI and asynchronous transfer mode (ATM). Afterburner can support transfers to and from the link adapter card at rates up to 1 Gbit/s. An implementation of TCP/IP that uses the features provided by Afterburner to reduce the movement of data to a single copy is discussed. Measurements of the end-to-end performance of Afterburner and the single-copy implementation of TCP/IP are presented. >

As virtualized data-centres become the back-end platforms behind a new generation of utility and cloud computing infrastructures (such as AmazonAWS [1]) their multi-tenancy, scale and complexity introduce new challenges that especially affect the networking layer. Multiple customers' requirements for varying logical network topologies must be simultaneously accommodated on the shared, underlying network fabric in a secure manner.Diverter is a new approach to network virtualization that targets these highly flexible, large-scale, multi-tenanted environments and advances the current state-of-the-art by implementing an efficient, fully distributed virtualized routing system that allows end-to-end communication between any endpoint with just a single network "hop". We have implemented a prototype of this solution that, in certain network configurations, achieves a throughput improvement of at least 66 % compared to alternative approaches.

Utility computing achieves efficiencies by dynamically reallocating shared resources between services operating on virtual clusters. These efficiencies can be hard to realize for data intensive applications; newly allocated nodes must be populated with a large amount of data which impedes rapid node reallocation. We describe a data management architecture that uses disk caches on each node to reduce data copying and speed up node reallocation for data intensive applications. Cache consistency management is simplified by extensive use of copy-on-write techniques. A data-driven scheme is then used to select nodes for reallocation between virtual clusters based on the amount of relevant cached data. These nodes are identified using a novel technique of statistically sampling the contents of caches. We demonstrate the benefits of this architecture using our implementation of an efficient block level caching and copy-on-write target for the Linux Device-mapper framework.

Previous studies have demonstrated that activated Tregs express latent TGF-β1 on their cell surface bound to the tethering molecule GARP. Although integrins have been implicated in mediating the release of biologically active TGF-β1 from the complex of latent TGF-β1 and latent TGF-β1 binding protein, their role in processing latent TGF-β1 from the latent TGF-β1/GARP complex is unclear. We detected integrin β8 expression by CD4+Foxp3+ Treg, but not by CD4+Foxp3- T cells, by qRT-PCR. Furthermore, integrin β8 expression appeared to be a marker of thymically-derived Treg (tTreg), as its could not be detected on Foxp3+ T cells induced in vitro nor in vivo on peripherally induced Foxp3+Helios- Tregs. While Tregs from integrin β8 conditional knockouts suppressed T effector cell proliferation normally in vitro and in vivo in a model of colitis, integrin β8 deficient Tregs failed to provide a source of TGF-β1 to drive Th17 or iTreg differentiation in vitro. In addition, the knockout Tregs expressed higher levels of latent TGF-β1 on their cell surface consistent with defective processing. Taken together, integrin β8 is not only a marker of tTregs, but also functions in a cell intrinsic manner as the major pathway for processing latent TGF-β1 from the latent TGF-β1/GARP complex on the surface tTregs.

GARP/LRRC32 has previously been defined as a marker of activated human regulatory T cells (Tregs) that is responsible for surface localization of latent TGF-β1. We find that GARP and latent TGF-β1 are also found on mouse Tregs activated via TCR stimulation, but in contrast to human Tregs, GARP is also expressed at a low level on resting Tregs. The expression of GARP can be upregulated on mouse Tregs by IL-2 or IL-4 exposure in the absence of TCR signaling. GARP is expressed at a low level on Tregs within the thymus and Treg precursors from the thymus concomitantly express GARP and Foxp3 upon exposure to IL-2. The expression of GARP is independent of TGF-β1 and TGF-β1 loading into GARP and is independent of furin-mediated processing of pro-TGF-β1 to latent TGF-β1. Specific deletion of GARP in CD4+ T cells results in lack of expression of latent-TGF-β1 on activated Tregs. GARP-deficient Tregs develop normally, are present in normal numbers in peripheral tissues, and are fully competent suppressors of the activation of T conventional cells in vitro. Activated Tregs expressing GARP/latent-TGF-β1 complexes are potent inducers of Th17 differentiation in the presence of exogenous IL-6. Induction of Th17 producing cells is preferentially induced by Tregs expressing the latent-TGF-β1/GARP complex on their cell surface rather than by secreted latent-TGF-β1.

The advantages of user-space protocols are well-known, but implementations often exhibit poor performance. This paper describes a user-space TCP implementation that outperforms a 'normal' kernel TCP and that achieves 80% of the performance of a 'single-copy' TCP. Throughput of 160 Mbit/s has been measured. We describe some of the techniques we used and some of the problems we encountered.

Two important questions in high-speed networking are firstly, how to provide Gbit/s networking at low cost and secondly, how to provide a flexible low-level network interface so that applications can control their data from the instant it arrives. We describe some work that addresses both of these questions. The Jetstream Gbit/s LAN is an experimental, low-cost network interface that provides the services required by delay-sensitive traffic as well as meeting the performance needs of current applications. Jetstream is a combination of traditional shared-medium LAN technology and more recent ATM cell- and switch-based technology. Jetstream frames contain a channel identifier so that the network driver can immediately associate an incoming frame with its application. We have developed such a driver that enables applications to control how their data should be managed without the need to first move the data into the application's address space. Consequently, applications can elect to read just a part of a frame and then instruct the driver to move the remainder directly to its destination. Individual channels can elect to receive frames that have failed their CRC, while applications can specify frame-drop policies on a per-channel basis. Measured results show that both kernel- and user-space protocols can achieve very good throughput: applications using both TCP and our own reliable byte-stream protocol have demonstrated throughputs in excess of 200 Mbit/s. The benefits of running protocols in user-space are well known- the drawback has often been a severe penalty in the performance achieved. In this paper we show that it is possible to have the best of both worlds.

In both mammals and non-mammalian models, exposure of BK (slo1) channels to ethanol concentrations reached in circulation during alcohol intoxication (10-100 mM) leads to changes in channel steady-state activity (NPo) and thus, perturbation of physiology and behavior (reviewed in: Brodie et al., 2007; Treistman & Martin, 2009; Dopico et al., 2012). Site(s) and mechanism(s) participating in ethanol-slo1 channel interactions are unknown. Using patch-clamp recording, point mutagenesis and computational modeling based on crystallographic data, we unveil that ethanol docks onto a water-accessible site that is strategically positioned between the slo1 calcium-sensors and gate. Ethanol only accesses this site in the presence of calcium, the slo1 channel's primary physiological agonist. Within the site, ethanol hydrogen-bonds with Lys361. Moreover, substitutions that frustrate this bonding (K361N) or prevent ethanol molecules from accessing Lys361 (S357Y) abolish alcohol action on slo1 NPo without altering basal channel function. After creating n-alkanol conformational libraries and using a docking routine to find representative poses for the n-alkanol molecules, we estimate that site dimensions are: 7.5x7.5x10A, this site accommodating effective (ethanol-heptanol) but not ineffective (octanol, nonanol) slo1 channel activators. This study presents: i) the first identification and characterization of an n-alkanol recognition site in a member of the voltage-gated TM6 channel superfamily; ii) structural insights on ethanol allosteric interactions with ion-gated ion channels, and iii) a first step for designing agents that antagonize BK channel-mediated alcohol actions without perturbing basal channel function. Support: R37AA11560 (AMD).