Medium Units Research Articles

Acompañar a los enfermos en la antesala del final de su ciclo vital

Objective: Perform an ethnography, palliative unit, to study the interactions of the actors, in particular that of doctors with patients, who are living this particular situation of transit to death; and the opinion of those on palliative care. Methodology: The paradigm that we ascribe is the qualitative, ontologically constructivist and epistemologically, from the point of view of the sociologies of life, still our method of Ethnography. Results: From the speech, mostly from interviews with doctors have been collected verbatim. Conclusions: Among other things, on the stage, a microspace within the Hospitalito, called care media unit, represents going back at other times the dichotomy thesis / antithesis, the thesis that it was a unit that it had formally inaugurated as a palliative unit, we assume that with a propaganda purpose, but the antithesis was the reality, and this was without a doubt that he was still a unit of care means.

Self-Assembly of Amphiphilic Homopolymers Bearing Ferrocene and Carboxyl Functionalities: Effect of Polymer Concentration, β-Cyclodextrin, and Length of Alkyl Linker

Three new acrylamide monomers containing ferrocene and tert-butyl ester groups were first synthesized via multistep nucleophilic substitution reaction under mild conditions followed by reversible addition-fragmentation chain transfer (RAFT) homopolymerization to give well-defined homopolymers with narrow molecular weight distributions (M(w)/M(n) ≤ 1.36). The target amphiphilic homopolymers were obtained by the acidic hydrolysis of tert-butyoxycarbonyls to carboxyls in every repeating unit using CF3COOH. The self-assembly behaviors of these amphiphilic homopolymers bearing both ferrocene and carboxyl moieties in each repeating unit in aqueous media were investigated by transmission emission microscopy (TEM), dynamic light scattering (DLS), and atomic force microscopy (AFM). Large compound micelles with different morphologies were formed by these amphiphilic homopolymers, which consist of the corona formed by hydrophilic carboxyls and the core containing numerous reverse micelles with hydrophilic islands of carboxyls in continuous hydrophobic phase of ferrocene-based segments. The morphologies of the formed micelles could be tuned by the concentration of amphiphilic homopolymers, pH value of the solution, the length of -CH2 linker between ferrocene group and carboxyl, and the amount of β-cyclodextrin (β-CD).

Comparison between conidia and blastospores of Esteya vermicola, an endoparasitic fungus of the pinewood nematode, Bursaphelenchus xylophilus

Esteya vermicola, an endoparasitic fungus of Bursaphelenchus xylophilus, the pinewood nematode (PWN), exhibits great potential as a biological control agent against this nematode. E. vermicola produces blastospores in liquid media and aerial conidia on solid media. The agent was mass-produced using two kinds of culture media: S (50% wheat bran and 50% pine wood powder), L (0.5g wheat bran and 0.5g pinewood powder in 200ml of potato dextrose broth), and two controls: SC (potato dextrose agar), LC (potato dextrose broth). Yields, multiple stress tolerance, storage life, new generation conidial number, and PWN mortality rates of the spores were measured in each of these four media and compared. The spore yields, new generation conidial number, and nematode mortality rates of blastospores were higher than those of conidia. Nevertheless, the conidia had a higher germination rate than the blastospores during the storage process and multiple stress treatments. Considering the number of spores surviving from the process of the storage and multiple stress treatments per unit of mass media, the blastospores from L survived most. Comprehensive analysis indicates that the L culture medium is the most optimal medium for mass production relatively.

Public Sentiment and Critical Framing in Social Media Content During the 2012 U.S. Presidential Campaign

By being embedded in everyday life, social networking sites (SNSs) have altered the way campaign politics are understood and engaged with by politicians and citizens alike. However, the actual content of social media has remained a vast but somewhat amorphous and understudied entity. The study reported here examines public sentiment as it was expressed in just over 1.42 million social media units on Facebook and Twitter to provide broad insights into dominant topics and themes that were prevalent in the 2012 U.S. election campaign online. Key findings include the fact that contrary to what one might expect, neither presidential candidate was framed in an overly critical manner in his opponent’s Facebook space nor on Twitter’s dedicated nonpartisan election page. Beyond this, similarities and divergences in sentiment across social media spaces are observed that allow for a better understanding of what is being communicated in political social media.

RNIB’s Talking Books engagement campaign: A case study

A recent report on social media suggests that consumer attitudes toward advertising within social networks are still evolving. It highlights that while roughly one-third of social media users find ads on social networking sites more annoying than other types of internet advertisements, there are opportunities for marketers to engage with consumers via social media. Rewarding users playing games within the social network environment in exchange for interacting with carefully selected brands (a value-exchange proposition) would suggest that any brand engagement could yield positive results. This case study shows how G Force Communications working with RNIB and the SocialVibe platform used video and a series of interactive questions to target women aged 45+. The engagement was served in a rich media unit within the social media games environment to build awareness and encourage click-through to a designated landing page in order to secure donations. Video as a communication medium has proved successful in the recruitment of new donors for RNIB Group in the past and by using existing footage the costs were relatively low. This was also seen as an opportunity to bring the challenges faced by the almost 2 million people in the UK living with sight loss to a wider audience.

Correlation of the R1 and R2 values of gadolinium-based MRI contrast media with the ΔHounsfield unit of CT contrast media of identical concentration

The optimal volume of contrast medium must be injected into the patient who emits the maximum signal intensity in an ROI. This study was investigated four different type MRI and one CT contrast agent in vitro and sought to establish relations between concentration, MRI relaxivity, CT Hounsfield unites selected kVp and different MRI T1 sequences. Using a CT contrast medium and four different MRI T1 contrast media, we developed five different phantom series. The MRI contrast media phantom was imaged on 1.5T and 3T MRI systems and measured the R1 and R2 value. A CT scanner was used to obtain images of the Iopromide 370 phantom with the quality of radiation to obtain images. The Pearson's correlation coefficient analyses were conducted between MRI CM phantom series with Iopromide 370 phantom. The non-parametric statistical analyses were performed for the values of kVp. The ΔHU of the test solution of the CT contrast media was produced in the same amount as the exponentially increased concentration of the MRI contrast media according to the increase in the dilution concentration, and was influenced by the quality of the X-ray. Through the results of this experiment that considered the two aforementioned factors, an image with a high diagnosis value can be acquired from the information on the concentration of the MRI T1 contrast media.

Proton-coupled electron transfer at a [Co-OHx]zunit in aqueous media: evidence for a concerted mechanism

The proton-coupled electron transfer (PCET) chemistry associated with the [Co-OH]2+/[Co-OH2]2+ redox couple for [Co(PY5)(OH2)]2+ (1; PY5 = 2,6-(bis(bis-2-pyridyl)-methoxymethane)-pyridine) and [CoII(pz4depy)(OH2)]2+ (2; pz4depy = 2,6-bis(1,1-di(1H-pyrazol-1-yl)ethyl)pyridine) is reported. It is found that the couple is acutely sensitive to the geometry of the axially ligated group in addition to the electronic-donating/-withdrawing character of the ligand. Interrogation of the electron-transfer kinetics by electrochemical methods also shows for the first time that the interconversion of [CoIII-OH]2+ and [CoII-OH2]2+ proceeds through a concerted pathway in favour of energetically unfavourable stepwise electron-transfer or proton-transfer reaction steps.

Extending information unit across media streams for improving retrieval effectiveness

This paper specifically addresses the effectiveness of our theoretically-based two dimensional retrieval model for searching semantically synchronized media streams. Conventional IR systems, which support partial retrieval of synchronized media streams, retrieve “atomic units”, for example slides, pages and shots of underlying media streams such as presentations, electronic books, and lecture videos respectively. In contrast, our model is based upon the concept of an extended retrieval unit and thus retrieves dynamically integrated media streams comprising several atomic units both along and across media streams. In this paper, in addition to reviewing our model, we describe its system implementation that we developed for conducting experiments on several real-world datasets built from scratch. We then present extensive empirical results which demonstrate that our system outperforms (a) conventional systems based on atomic retrieval units, (b) single dimensional retrieval systems, which extend retrieval units over several atomic units of the same media and (c) cross-media retrieval systems, which extend atomic retrieval units across several media stream units. The results thus verify our claims regarding the effectiveness of our two dimensional retrieval model for retrieving meaningful units of synchronized media streams.

Semantic annotation and retrieval of documentary media objects

PurposeThis paper aims to propose a system for the semantic annotation of audio‐visual media objects, which are provided in the documentary domain. It presents the system's architecture, a manual annotation tool, an authoring tool and a search engine for the documentary experts. The paper discusses the merits of a proposed approach of evolving semantic network as the basis for the audio‐visual content description.Design/methodology/approachThe author demonstrates how documentary media can be semantically annotated, and how this information can be used for the retrieval of the documentary media objects. Furthermore, the paper outlines the underlying XML schema‐based content description structures of the proposed system.FindingsCurrently, a flexible organization of documentary media content description and the related media data is required. Such an organization requires the adaptable construction in the form of a semantic network. The proposed approach provides semantic structures with the capability to change and grow, allowing an ongoing task‐specific process of inspection and interpretation of source material. The approach also provides technical memory structures (i.e. information nodes), which represent the size, duration, and technical format of the physical audio‐visual material of any media type, such as audio, video and 3D animation.Originality/valueThe proposed approach (architecture) is generic and facilitates the dynamic use of audio‐visual material using links, enabling the connection from multi‐layered information nodes to data on a temporal, spatial and spatial‐temporal level. It enables the semantic connection between information nodes using typed relations, thus structuring the information space on a semantic as well as syntactic level. Since the description of media content holds constant for the associated time interval, the proposed system can handle multiple content descriptions for the same media unit and also handle gaps. The results of this research will be valuable not only for documentary experts but for anyone with a need to manage dynamically audiovisual content in an intelligent way.

A joint layered scheme for reliable and secure mobile JPEG-2000 streaming

This article presents a novel joint layered approach to simultaneously achieve both reliable and secure mobile JPEG-2000 image streaming. With a priori knowledge of JPEG-2000 source coding and channel coding, the proposed joint system integrates authentication into the media error protection components to ensure that every source-decodable media unit is authenticated. By such a dedicated design, the proposed scheme protects both compressed JPEG-2000 codestream and the authentication data from wireless channel impairments. It is fundamentally different from many existing systems that consider the problem of media authentication separately from the other operations in the media transmission system. By utilizing the contextual relationship, such as coding dependency and content importance between media slices for authentication hash appending, the proposed scheme generates an extremely low authentication overhead. Under this joint layered coding framework, an optimal rate allocation algorithm for source coding, channel coding, and media authentication is developed to guarantee end-to-end media quality. Experiment results on JPEG-2000 images validate the proposed scheme and demonstrate that the performance of the proposed scheme is approaching its upper bound, in which case no authentication is applied to the media stream.

Optimizing Selective ARQ for H.264 Live Streaming: A Novel Method for Predicting Loss-Impact in Real Time

This work proposes a quality-oriented, real-time capable prioritization technique for media units of H.264/AVC video streams. The derivation of estimates is based on the analysis of the macroblock partitioning, the spatial extents of temporal dependencies, and the length and strength of prediction chains existing among macroblocks, thus incorporating the expected impact of error propagation. It is demonstrated how the prioritization scheme can be beneficially integrated into live streaming systems which are characterized by tight timing constraints, with the focus on content-aware selective automatic repeat request mechanisms. Additionally, it is shown how potentially limited feedback can be used to adapt the estimation process to leverage prediction preciseness. The approach is compared against existing techniques in terms of practicability and efficiency, and tested under independent and bursty loss conditions in a wired and a wireless test setup. Moreover, the performance is examined when low-latency and constant bitrate video settings are enforced by using x264's novel encoding feature periodic-intra-refresh. Results of both experiments and simulations indicate that the proposed technique outperforms all reference techniques in nearly all test cases, and that the video quality can be further improved by incorporating receiver feedback.

A Two-Stage Wood Chip-Based Biofilter System to Mitigate Odors from a Deep-Pit Swine Building

A mobile biofilter testing laboratory was developed where two-stage biofilters filled with western cedar and hardwood chips were examined to treat odor emissions from a deep-pit swine finishing facility in central Iowa. An automatically controlled water supply system was tested and used to control media moisture content. Odor concentrations from theinlet and biofilter treatments, gas flow pressure drop, leachate pH and ammonia concentration, and water consumption were monitored.Results indicate that the water supply system tested in this study can keep wood chip media at a high and stablemoisture content of 72% 3% (western cedar) and 62% 3% (hardwood)with a 6.4 L/m3-day water supply. Western cedar (WC) chips achieved an average reduction efficiency of 51%, 83%, and 41% for odor, H2S, and NH3, respectively, when keeping the WC moisture content at 72% and the empty bed residence time (EBRT) between 3.7 and 5.5 s. A linear relationship between media unit pressure drop and unit airflow rate was observed with two-stage biofilters having an advantage in potentially reducing media compaction.Leachate pH and NH3 concentration were measured with pH levels in the 7.2 to 7.9 range with the NH3 concentration in the 198 to 1300 mg/L as N range.The effects of three different levels of media moisture content shows that proper moisture content is a key factor for the success of wood chip biofilters, but is not a substitute for inadequate EBRT.

Media: An Uneasy Relationship

In 1989, corruption inquiry commissioner Tony Fitzgerald, QC gave a qualified tick to the use of government media units and press secretaries in his landmark report, which ushered Queensland into an age of accountability.After an inquiry that included 238 public sitting days and 339 witnesses, his view was that it was both ‘legitimate and necessary’ for ministers, departments and public instrumentalities to employ staff to help keep the public informed. He warned, however, against control and manipulation of information and counselled there was no legitimate justification for politically motivated propaganda funded by taxpayers:The only justification for press secretaries and media units is that they lead to a community better informed about government and departmental activities. If they fail to do this then their existence is a misuse of public funds, and likely to help misconduct to flourish.

‘Cop[ying] it Sweet’: Police Media Units and the Making of News

Over the past two decades police media units have played an ever-increasing role in managing the dissemination of information between the police and media organisations. Using the example of the New South Wales Police Media Unit in Australia (hereafter NSW PMU) this article assesses the journalistic deployment of PMU information and develops a broader sociopolitical argument explaining the growth of PMUs more generally. We analyse qualitative research data, in the form of interviews with journalists and NSW PMU staff (n = 29), and quantitative data from an analysis of two Sydney-based daily newspapers. We suggest that the growth of PMUs can be explained with reference to new programs of governing crime that developed throughout the last quarter of the 20th century as well as significant changes to the global media landscape.

Application-Level QoS and QoE Assessment of a Cross-Layer Packet Scheduling Scheme for Audio-Video Transmission over Error-Prone IEEE 802.11e HCCA Wireless LANs

This paper proposes a cross-layer packet scheduling scheme for QoS support in audio-video transmission with IEEE 802.11e HCCA and assesses application-level QoS and QoE of the scheduling scheme under lossy channel conditions. In the proposed scheme, the access point (AP) basically allocates transmission opportunity (TXOP) for each station in a service interval (SI) like the reference scheduler of the IEEE 802.11e standard, which is referred to as the TGe scheme in this paper. In the proposed scheme, however, the AP calculates the number of MAC service data units (MSDUs) arrived in an SI, considering the inter-arrival time of audio samples and that of video frames, which are referred to as media units (MUs), at the application layer. The AP then gives additional TXOP duration in the SI to stations which had audio or video MAC protocol data units (MPDUs) in their source buffers at the end of the previous TXOP. In addition, utilizing video frame information from the application layer, we propose video frame skipping at the MAC-level of a source station. If a station fails to transmit a video MPDU, it drops all the following video MPDUs in the source buffer until the next intra-coded frame comes to the head of the buffer. We compare the reference scheduler (TGe scheme), the proposed packet scheduling scheme with and without the video frame skipping at the source in terms of application-level QoS and QoE. We discuss the effectiveness of the proposed packet scheduling scheme from a viewpoint of QoE as well as QoS. Numerical results reveal that the proposed packet scheduling scheme can achieve higher quality than the TGe scheme under lossy channel conditions. We also show that the proposed scheduling scheme can improve the QoS and QoE by using the video frame skipping at the source. Furthermore, we also examine the effect of SI on the QoS and QoE of the proposed packet scheduling scheme and obtain that the appropriate value of SI is equal to the inter-arrival time of video frame.

Ausland Die Bibliotheca Alexandrina: Eine sich selbst erfindende Bibliothek des Lehrens und Lernens

Since the opening of the Bibliotheca Alexandrina in October 2002, the library has become one of the most important places for learning and research in the Middle East. Signs for the success are the number of media units (appr. 800.000), patrons (appr. 15.000), staff (appr. 2.000), training programmes (about 800 per year) and the quality of international conferences. Despite the high standard of architecture and technical equipment, in this paper problems of the aquisition unit, the standard of eaducation and the information policy in Egypt are discussed.

Towards Photographic Education

In light of the triumph of the digital photograph as the basic semantic unit of New Media, this paper investigates the response of photographic education to the culture of ubiquitous mobile and networked photography. It argues that photographic education fails to address such contemporary conditions as the crisis of the visual, the demise of the still photograph and the redundancy of the notion of authorship because it perceives the digital turn in technological terms. This paper suggests that if the digital moment in photography will be approached conceptually rather than technologically, it will present photography educators with a unique opportunity to place the study of the digital photograph at the centre of a culture which is based on reproduction, multiplication and copying.

Application-Level QoS and QoE Assessment of Audio-Video Transmission with TXOP-Bursting by IEEE 802.11e EDCA

This paper assesses application-level QoS and Quality of Experience (QoE) in the case where audio and video streams are transferred with the enhanced distributed channel access (EDCA) of the IEEE 802.11e MAC. In EDCA, a station can transmit multiple MAC frames during a transmission opportunity (TXOP); this is referred to as TXOP-bursting. By simulation, we first compare application-level QoS with the TXOP-bursting scheme and that without the scheme for various distances between access point (AP) and stations. In this paper, we suppose that the bit error rate (BER) becomes larger as the distance increases.Numerical results show that TXOP-bursting can improve many metrics of video quality such as average media unit (MU) delay, MU loss ratio, and media synchronization quality, particularly when the AP sends audio and video streams to stations in the downlink direction. We then examine the effect of TXOPLimit on the video quality. Simulation results show that the video quality can be degraded if the value of TXOPLimit is too small. Furthermore, we assess QoE by the method of successive categories, which is a psychometric method. Numerical results show that TXOP-bursting can also improve the QoE. We also perform QoS mapping between application-level and user-level with principal component analysis and multiple regression analysis.

Adaptive playout scheduling algorithm tailored for real-time packet-based voice conversations over wireless ad-hoc networks

The effective provision of real-time, packet-based voice conversations over multi-hop wireless ad-hoc networks faces several stringent constraints not found in conventional packet-based networks. Indeed, MANETs (mobile ad-hoc networks) are characterized by mobility of all nodes, bandwidth-limited channel, unreliable wireless transmission medium, etc. This environment will surely induce a high delay variation and packet loss rate impairing dramatically the user experienced quality of conversational services such as VoIP. Indeed, such services require the reception of each media unit before its deadline to guarantee a synchronous playback process. This requirement is typically achieved by artificially delaying received packets inside a de-jitter buffer. To enhance the perceptual quality the buffering delay should be adjusted dynamically throughout the vocal conversation. In this work, we describe the design of a playout algorithm tailored for real-time, packet-based voice conversations delivered over multi-hop wireless ad-hoc networks. The designed playout algorithm, which is denoted MAPA (mobility aware playout algorithm), adjusts the playout delay according to node mobility, which characterizes mobile ad-hoc networks, and talk-spurt, which is an intrinsic feature of voice signals. The detection of mobility is done in service passively at the receiver using several metrics gathered at the application layer. The perceptual quality is estimated using an augmented assessment approach relying on the ITU-T E-Model paradigm while including the time varying impairments observed by users throughout a packet-based voice conversation. Simulation results show that the tailored playout algorithm significantly outperforms conventional playout algorithms, specifically over a MANET with a high degree of mobility.

An adaptive media playout for intra-media synchronization of networked-video applications

Adaptive media playout (AMP) aims to improve the media synchronization quality of streaming applications by regulating the playout time interval among media units (MUs) at a receiver. In this paper, we introduce an AMP scheme based on a discontinuity model for intra-media synchronization of video applications over the best-effort networks. We analyze the temporal distortion (i.e., discontinuity) cases, such as playout pause and skip, to define a unified discontinuity model. Based on the discontinuity model, an objective intra-media synchronization quality metric is defined as the root mean square error (RMSE) of discontinuity. After that, we establish a practical algorithm that enables an efficient playout speed control to enhance the intra-media synchronization quality. Simulation results verify the enhanced intra-media synchronization quality through comparison with a conventional buffer-threshold-based scheme.