Статті в журналах з теми "Telephone Signaling"

[Six cases of birds trapped in telephone wires or in structures connected to telephone wires were signaled in the areas of Turin and Novara (Piedmont, N. W. Italy). The birds stayed hanging fatally either by chance or during a trophic activity. The species involved in the described episodes are five, but become eight when added to the ones subjects of previous signaling: Little bitten Ixobrychus minutus, Grey heron Ardea cinerea, Moorhen Gallinula chloropus, Barn owl Tyto alba, Little owl Athene noctua, Robin Erithacus rubecula, Starling Sturnus vulgaris, Hooded crow Corvus corone cornix.] [Article in Italian]

One benefit of Common-Channel Signaling (CCS), a new signaling system developed for telephone network applications, would be greatly reduced post-dialing delays. The question addressed was whether unilateral introduction of CCS in either the toll or local network would negatively affect caller behavior in the other network. Results indicate that a CCS toll network would increase caller impatience and abandonments on local calls but not vice versa. Implications of this effect are considered and felt to be far outweighed by the benefits of the CCS system.

In recent years, the coverage of terrestrial mobile communication network is more and more extensive, and the mobile phones have occupied the vast majority of voice communications in almost all countries. However, satellite voice communication system is still playing an irreplaceable role on the vast sea and the land area which are not covered by the land mobile communication network. The motion characteristics of the SIGSO satellites and its new demands and characteristics to the system are analyzed, and a novel very low rate satellite telephone system is put forward. The speech coding algorithms are studied, and a suitable speech coding algorithm and coding rate of 600bps is selected for the SIGSO satellite communication system. The overall design of the satellite voice communication network is given, including link budgets, network structure, system components, system signaling and so on. This satellite telephone system can get access to the PSTN network through ground gateway to achieve interoperability with the public network.

Improving voice quality over wireless communication becomes a demanding feature for social media apps like facebook, whatsapp and other communication channels. Voice-over-internet protocol (VoIP) helps us to make quick telephone calls over the internet. It includes various mechanism which are signaling, controlling and transport layer. Over wireless links, packet loss and high transmission delay damage voice quality. Here VoIP quality will be measured by three main elements which are signaling protocol, audio codec and transport layer. To improve the overall voice quality, we need to combine these three elements properly to get the best score. Otherwise perceptual speech quality will not be the right tool to measure the voice quality. Here we will use Mean Opinion Score (MOS) for calculated jitter values and end to end delay. At the end, best combination of audio codec signaling protocol produced the quality speech.

The rapidly evolving communication system enables applications for telephone communication to be carried over the data network known as VoIP (voice over internet protocol). SIP (session initiation protocol) as the signaling protocol is text-based VoIP which can be implemented easily in comparison with other signalingprotocols. The purpose of this paper is designing and implementing VoIP billing up to the company to provide additional facilities for enterprise customers. The methods start with data collection, analysis, design, development, and implementation. The result achieved is a system of VoIP with SIP and Asterisk software which has functions of PBX to provide additional facilities such as VoIP which is a plus for the company and customers. After implemented, the VoIP system and billing features are found work well.

Voice over Internet Protocol (VoIP) has been recently one of the more popular applications in Internet technology. It benefits lower cost of equipment, operation, and better integration with data applications than voice communications over telephone networks. However, the voice packets delivered over the Internet are not protected. The session initiation protocol (SIP) is widely used signaling protocol that controls communications on the Internet, typically using hypertext transport protocol (HTTP) digest authentication, which is vulnerable to many forms of attacks. This paper proposes a new secure authentication and key agreement scheme based on Digital Signature Algorithm (DSA) and Elliptic Curve Cryptography (ECC) named (ECDSA). Security analysis demonstrates that the proposed scheme can resist various attacks and it can be applied to authenticate the users with different SIP domains.

Introduction/purpose: To specify the practical application of ECMA355 and ECMA-336 Standards for Q-SIG tunneling and the implementation of mapping functions via the existing IP (Internet Protocol) network of the Serbian Armed Forces (Intranet SAF), in the Private Automatic Telephone Network SAF (PATN SAF), as the main part of the Private telecommunication-information networks of integrated services SAF (PISN SAF). Methods: Description of the implemented solution and analysis of the software parameters of the established transmission SIP route, with the display of the results obtained in the fight with jitter and echo in the network. Results: With such a solution, it was achieved that participants from the peripheral parts of the PISN SAF, which operate on the principle of transmission and circuit switching by TDM (Time Division Multiplexing), can connect with each other via the newly established central IP network SAF (Core network) which operates on the principle of transmission and switching packets with the SIP (Session Initiation Protocol), without losing the functionality of QSIG from the framework of the digital telecommunication network of integrated services ISDN (Integrated Services Digital Network). Conclusion: The article deals with the modern IP PINX (Private Integrated Services Network Exchange) manufactured by Mitel, type MX-ONE Service Node 6.0, which is implemented at the transit level PATN SAF and which successfully implements the process of tunneling Q-SIG through the IP network and the necessary functions for mapping the transmission of tunneled QSIG messages and mapping voice (and other audio) information to VoIP (Voice over IP) communication media streams through that network. Also, the basic elements for its software preparation during the introduction of a new SIP route, with a capacity of 30 IP trunks in a transmission beam realized with 100 Mb/s-T Ethernet, are given, and the fight with the present jitter and echo in the network is described. Finally, the paper presents the experience-based values of the parameters for reducing the influence of jitter and suppressing echo.

Music is a peculiar human behavior, yet we still know little as to why and how music emerged. For centuries, the study of music has been the sole prerogative of the humanities. Lately, however, music is being increasingly investigated by psychologists, neuroscientists, biologists, and computer scientists. One approach to studying the origins of music is to empirically test hypotheses about the mechanisms behind this structured behavior. Recent lab experiments show how musical rhythm and melody can emerge via the process of cultural transmission. In particular, Lumaca and Baggio (2017) tested the emergence of a sound system at the boundary between music and language. In this study, participants were given random pairs of signal-meanings; when participants negotiated their meaning and played a “game of telephone” with them, these pairs became more structured and systematic. Over time, the small biases introduced in each artificial transmission step accumulated, displaying quantitative trends, including the emergence, over the course of artificial human generations, of features resembling properties of language and music. In this Note, we highlight the importance of Lumaca and Baggio's experiment, place it in the broader literature on the evolution of language and music, and suggest refinements for future experiments. We conclude that, while psychological evidence for the emergence of proto-musical features is accumulating, complementary work is needed: Mathematical modeling and computer simulations should be used to test the internal consistency of experimentally generated hypotheses and to make new predictions.

Introduction/purpose: The article should specify the network signaling type Q-SIG, which is standardized especially for implementation in digital telecommunication networks of integrated services (ISDN), emphasizing the possibility of its further application in the Private Telecommunications Network of Integrated Services of the Serbian Armed Forces (PISN of SAF), i.e. in the Private Automatic Telephone Network of the Serbian Armed Forces (PATN of SAF). Methods: An analysis of the existing standards was performed: ECMA355 and ECMA-336 and a synthesis of the possibilities of their application in the PATN of SAF. Results: The procedure for the application of Q-SIG is processed in a situation when the peripheral parts of the PISN of SAF, which operate on the principle of transmission and circuit switching by TDM (Time Division Multiplexing), are connected via a central Core network with the IP (Internet Protocol), which operates on the principle of packet transmission and switching with the SIP (Session Initiation Protocol). A method of the application of the tunneling of encapsulated Q-SIG messages through the IP network, defined by ECMA-355 Standard, has been developed. The necessary functions for mapping the transmission of tunneled signaling messages Q-SIG and mapping voice (and other audio) information to media streams during VoIP (Voice over IP) communication through that network, which are defined by ECMA-336 Standard, are described. Conclusion: The application of ECMA-355 and ECMA-336 Standards is a new solution in the PATN of SAF with the use of the IP network to connect the IP PINX using the Q-SIG tunneling procedures and mapping functions for their transmission and transmission of audio signals. This then opens up a whole range of new possibilities that, with the growth of the Core network and their application, will rapidly contribute to the creation of a broad Telecommunication information system backbone for the implementation of real-time multimedia communications and the transition to Unified Communications (UC).

The tone used in the new service Caller ID on Call Waiting (CIDCW) must be reliably detected by customer premises equipment (CPE), so that it can prepare to receive caller ID data, and it should alert customers to new calls but without being annoying. To help select a tone, the first experiment of this study examined the acceptability of a series of high-frequency dual tones that might be able to perform the required CPE signaling. Subjects were presented with the tones under circumstances in which they would typically be heard (while talking and listening over the telephone) and rated the sound quality of the tones. Long bursts of tones were presented as well as short bursts prepended or appended to the 440-Hz tone used in Call Waiting service. The results suggested that customers may find high-frequency dual tones acceptable. To determine acceptable parameters of tones, in the second experiment, subjects rated the loudness of selected tones as their length and power were varied.

The transcriptional network determines a cell’s internal state by regulating protein expression in response to changes in the local environment. Due to the interconnected nature of this network, information encoded in the abundance of various proteins will often propagate across chains of noisy intermediate signaling events. The data-processing inequality (DPI) leads us to expect that this intracellular game of “telephone” should degrade this type of signal, with longer chains losing successively more information to noise. However, a previous modeling effort predicted that because the steps of these signaling cascades do not truly represent independent stages of data processing, the limits of the DPI could seemingly be surpassed, and the amount of transmitted information could actually increase with chain length. What that work did not examine was whether this regime of growing information transmission was attainable by a signaling system constrained by the mechanistic details of more complex protein-binding kinetics. Here we address this knowledge gap through the lens of information theory by examining a model that explicitly accounts for the binding of each transcription factor to DNA. We analyze this model by comparing stochastic simulations of the fully nonlinear kinetics to simulations constrained by the linear response approximations that displayed a regime of growing information. Our simulations show that even when molecular binding is considered, there remains a regime wherein the transmitted information can grow with cascade length, but ends after a critical number of links determined by the kinetic parameter values. This inflection point marks where correlations decay in response to an oversaturation of binding sites, screening informative transcription factor fluctuations from further propagation down the chain where they eventually become indistinguishable from the surrounding levels of noise.

Many companies have transformed their telephone systems into Voice over IP (VoIP) systems. Although implementation is simple, VoIP is vulnerable to different types of attacks. The Session Initiation Protocol (SIP) is a widely used protocol for handling VoIP signaling functions. SIP is unprotected against attacks because it is a text-based protocol and lacks defense against the growing security threats. The Distributed Denial of Service (DDoS) attack is a harmful attack, because it drains resources, and prevents legitimate users from using the available services. In this paper, we formulate detection of DDoS attacks as a classification problem and propose an approach using token embedding to enhance extracted features from SIP messages. We discuss a deep learning model based on Recurrent Neural Networks (RNNs) developed to detect DDoS attacks with low and high-rate intensity. For validation, a balanced real traffic dataset was built containing three attack scenarios with different attack durations and intensities. Experiments show that the system has a high detection accuracy and low detection time. The detection accuracy was higher for low-rate attacks than that of traditional machine learning.

Purpose: Among the communication methods significant to diplomacy is signaling. Signaling in diplomacy is characterized by ambiguity that is deemed creative as well as constructive. The overall objective of this study was to examine use of E-government technologies in Kenyan foreign affairs diplomacy. Methodology: The paper used a desk study review methodology where relevant empirical literature was reviewed to identify main themes and to extract knowledge gaps. Findings: This study concluded that that there are several studies that have explored the concept of digital diplomacy at various levels of analysis especially in the developed countries. Nonetheless, there were several gaps identified when it came to examining the concept of digital diplomacy in developing countries particularly those in the African continent. Diplomatic communication was noted to have transitioned as communication did. Some of the notable communication technologies that have influenced diplomatic communication included the telegraph, air mail, radio, television, telephone and modern-day information communication technologies. Unique Contribution to Theory, Policy and Practice: This study recommended that in addition to the efforts of further equipping the ministry with high tech digital equipment’s, the Ministry of Foreign Affairs and International Trade needs to consider that digital resources toolkits should be matched with the needs of digital diplomacy. This is because certain pieces of technology are best suited in pursuant of identified foreign policy objectives. Moreover, procuring of digital resources should be matched with extensive training of the staff on how they can utilize them to achieve maximum benefits.

This study investigated the nature and level of market-oriented sustainability of Sjenica sheep cheese, a Serbian Protected Designation of Origin (PDO)-registered product. In the analysis of the supply chain market sustainability, three theories were used: Resource dependence theory, upper echelons theory, and signaling theory. The data were collected using a stepwise research design, applying techniques of observation and in-depth and telephone interviewing. The results show that the low recognition of the PDO label among Serbian consumers and all participants in the supply chain and the lack of the presence in the markets and large packages negatively impact domestic consumers in their decisions to purchase higher amounts of Sjenica sheep cheese. Small producers lack bargaining power, whereas their perceptions hinder formation of inter-organizational arrangements. The insufficient education of big producers and distributors impede the achievement of better business results. The main challenges for the export of Sjenica sheep cheese are the inadequate certification of this food product for the European Union market, the lack of standardized production process that results in variations in the product quality, and the unawareness of the regional consumers of Sjenica sheep cheese due to insufficient communication efforts.

Background Alpha globin is expressed in the endothelial cells of human resistance arteries where it binds to endothelial nitric oxide synthase and limits release of the vasodilator nitric oxide. Genomic deletion of the alpha globin gene (HBA) is common among Black Americans and could lead to increased endothelial nitric oxide signaling and reduced risk of hypertension. Methods Community-dwelling US adults aged 45 years or older were enrolled and examined from 2003 to 2007, followed by telephone every 6 months, and reexamined from 2013 to 2016. At both visits, trained personnel performed standardized, in-home blood pressure measurements and pill bottle review. Prevalent hypertension was defined as systolic blood pressure ≥ 140mmHg or diastolic blood pressure ≥ 90mmHg or anti-hypertensive medication use. Droplet digital PCR was used to determine HBA copy number. The associations of HBA copy number with prevalent hypertension, resistant hypertension, and incident hypertension were estimated using multivariable regression. Results Among 9,684 Black participants, 7,439 (77%) had hypertension at baseline and 1,044 of those had treatment-resistant hypertension. 1,000 participants were not hypertensive at baseline and participated in a follow up visit; 517 (52%) developed hypertension over median 9.2 years follow-up. Increased HBA copy number was not associated with prevalent hypertension (PR = 1.00; 95%CI 0.98,1.02), resistant hypertension (PR = 0.95; 95%CI 0.86,1.05), or incident hypertension (RR = 0.96; 95%CI 0.86,1.07). Conclusions There were no associations between increased HBA copy number and risk of hypertension. These findings suggest that variation in alpha globin gene copy number does not modify the risk of hypertension among Black American adults.

The goal of this qualitative single-case study was to investigate the problem with more than 50% of Americans admitting they are not prepared for natural disasters before they occur. The sample for this study was 24 purposively selected Hurricane Sandy survivors in New York and New Jersey who were 25 years of age or older. Data was collected through ten open-ended interview questions presented during telephone interviews. This study was guided by the theoretical framework of normative risk management decision making. Thematic analysis was used to code and analyze the data collected. This study was focused on answering two broad research questions related to why more than 50% of Americans are not prepared for natural disasters before they occur and the factors that prevent them from preparing. The major recommendations for future research and practice were related to the lack of a distinction between individuals who perceive they are prepared (who are deemed unprepared according to regulatory guidelines) and the possibility they are included with the more than 50% of Americans who are not prepared although they require modification of preparedness behavior while individuals who are not prepared require adoption of preparedness behavior. The other recommendations describe the factors that prevent individuals from preparing as lack of notification and signaling communications that indicate a natural disaster is imminent and expected to be severe; and individual disbelief in the validity of the communications. This study contributes to filling the gap in the literature related to the lived experience with natural disasters.

Abstract: VoIP technology is equipped with several functions, namely, the signalling function, meaning the VoIP is in charge of receiving the network from the caller, after which the conversation delivered. This technology is capable to pass voice traffic in the form of packets over an IP network. Packets of sound undergo a long process or delay to get to the destination it can damage the voice’s quality being heard. It happened because there is continuous delay in the communication between IP phone set on VoIP technology that causes echo in the receiver’s voice. Echo can occur during communication with IP phone set with average delay capacity above 5ms. The delay on the delivery and reception as in the results of communication between telephones can be adjusted for sound frequency of 300 Hz to 1000 Hz as a cut off by adding High Pass Filter (HPF) application. HPF filter application is able to stabilize the amplitude of about -21 dBm from the set of transmission test on the receiver when there is weakening at low frequencies, but when the frequency is raised to 1500-2250 Hz the amplitude strengthens to -12,2 dBm or increases the value of about 8.8 dB. Meanwhile, for the lower frequency such as 300 – 950 Hz, the filter would not pass it since the frequency is designed to be cut-off at 1000 Hz. The value of delay is narrower to 0.08ms by HPF application at the frequency of sound upper limit received by any 1000-3400 Hz telephone set. Keywords: VoIP technology, echo cancelling, HPF filter, delay, voice quality

The significance of this thesis is that the function of call simulation is designed to satisfy the operator’s needs. Operators can diagnose whether the telephony applications proceed normally by manipulating the VOIP(Vocie Over IP) telephony terminals on ITMS(Integrated Terminal Management System) platform remotely, by which way, it can help operators to save large manual and material resources. And this thesis focuses on how to realize the function of call simulation on VOIP phone terminals. It firstly studies the related modules in the process of call simulation and the procedures of each modules cooperated, from a macro point of view. And then it focuses on elaborating the scheme of designing call simulation, including the design of simulation applications for call and called sides and design of simulation signal process in the situation of normal calling. In the testing step, it turns on to validate and realize the goal of manipulating and diagnosing the telephony applications by packeting the communication’s terminal , analyzing signaling streams, etc,.

Scalability is an important aspect of communication networks. With the ascent of SIP and associated modern real-time protocols, IP telephony has become a revolutionary technology in connecting users through real-time voice communications with enabled video and instant messaging capabilities. B2BUA is a SIP server that provides call management and authentication functionality by reformulating the request and routing the traffic to other user agents in the network. It comprises signaling and media entities that handle all control signaling messages and real-time data(media) information respectively. The signaling and entities run as different processes in the same container. Such an architecture encounters a large CPU utilization after a specific number of maximum calls due to increase traffic flowing within the same node. Further Packet processing is CPU intensive and there is a need for an architecture that scales well with increasing traffic without hitting the CPU performance. The paper presents the design of decoupled architecture for Signaling and Media entities by running both the processes in different containers. With such an approach, one Signaling entity can communicate with multiple Media entities or vice versa thereby providing a suitable scalable solution to deal with the increased traffic and further maintaining the system efficiency. The paper is concluded by highlighting the difference between Kubernetes and OpenStack for the proposed architecture

Web Real-Time Communications (WebRTC) technology is an enabler of native transmission of multimedia information between two and more Web browsers. WebRTC is based on HTML version 5 (HTML5) and JavaScript languages. Although both real-time media streams (audio, video) and non-real-time non-media flows (also present in WebRTC architecture) are transmitted directly between browsers, to enable transmission of information necessary for session management (and more precisely: session establishment) purposes, a signalling server is needed. Such server may be regarded as a rendezvous point of end systems that use WebRTC technology. In this paper, node.js run-time environment and principle of building of Webrtc signalling server with the use of scripts written in JavaScript and run in node.js are presented. Example of script of a simple signalling server also is shown. The exemplary server connects users of one and only session, although this session may serve not only one-to-one, but also many-to-many connections. Despite its simplicity, this is a fully functional signalling server, able to serve signalling messages for purposes of message ex-change, or for purposes of initialization of WebRTC-based Internet telephony or simple conferencing systems.

A closer look into the history of maritime geomedia reveals a historical intermezzo in which navigation in cases of unstable sight was realized with “Submarine Signaling” (SS). This infrastructure for the purpose of safe wayfinding along coasts operated from around 1900 to the early 1920s, relying upon submarine bells in the global oceans, and hydrophones and telephonic user interfaces in vessels. SS can be regarded as a starting point to the era of electrotechnological navigation, and is of media-historical interest insofar as its operability was based on undersea acoustics: shifting its epistemic focus from sight to sound, SS thus lay beyond the “visual regime” that characterizes our current digital geomedia cultures. Herein, I will reconstruct the genesis and history of SS, use it as a contrasting foil to our postmodern geomedia practices, and finally argue for an understanding of geomedia as historically variable phenomena.

Session Initiation Protocol (SIP) is an application layer protocol designed to control and establish multimedia sessions over internet. SIP gaining more and more popularity as it is used by numerous applications such as telephony over IP(ToIP). SIP is a text based protocol built on the base of the HTTP and SMTP protocols. SIP suffers from certain security threats which need to be resolved in order to make it a more efficient signaling protocol. In this work, we review the proposed works aimed to detect SIP malformed messages that can cause security problem. Then, we classify the type of malformed SIP message and compare between the mechanisms used to reinforce the detection of malformed SIP message attack.

The Session Initiation Protocol (SIP) is one of the most common protocols that are used for signaling function in Voice over IP (VoIP) networks. The SIP protocol is very popular because of its flexibility, simplicity, and easy implementation, so it is a target of many attacks. In this paper, we propose a new system to detect the Denial of Service (DoS) attacks (i.e. malformed message and invite flooding) and Spam over Internet Telephony (SPIT) attack in the SIP based VoIP networks using a linear Support Vector Machine with l1 regularization (i.e. l1-SVM) classifier. In our approach, we project the SIP messages into a very high dimensional space using string based n-gram features. Hence, a linear classifier is trained on the top of these features. Our experimental results show that the proposed system detects malformed message, invite flooding, and SPIT attacks with a high accuracy. In addition, the proposed system outperformed other systems significantly in the detection speed.

Òhe functional architecture of the subsystem picture messaging-IMS (Internet Protocol Multimedia Subsystem) for multimedia session management for multiservice NGN/IMS networks that determine the interaction systems and NGN protocols are investigated. The basic element of the IMS core network architecture are session control function CSCF (Call/Session Control Function) which is implemented on the SIP-server (Session Initiation Protocol) using the protocol. A block diagram of the functioning of the traffic service model of multimedia services in the NGN/IMS network when establishing sessions that use the network elements of the user data server HSS (Home Subscriber Server), CSCF control system core, signaling and media gateways (SGW & MGW, Signaling Gateway & Media Gateway). The characteristics of the effectiveness of the IMS and found that in the NGN / IMS multimedia services network in real time significantly alter the traffic characteristics as a service, and efficiency, which requires new models and approaches to assess the main indicators of quality of the service Triple Play. Based on the analysis of the quality NGN/IMS networks in the provision multimedia services, the mathematical model for evaluating the quality of services. This model takes into account the properties of self-similar random process with Hurst index and describes the quality of functioning of NGN/IMS architectural concept. Based on the model studied when performing voice services with the ability to activate multimedia applications, video telephony, multimedia traffic, Triple Play services. According to the study of mathematical models of NGN / IMS networks using SIP-servers analytical expressions to assess the indicators of a common set of operating characteristics of IP-based networks, which take into account the recommendations of ITU-T Y.1540 and Y.2000 and determined the average waiting time in the queue IMS system in the provision of multimedia services with the required parameters, providing a guaranteed quality of service QoS (Quality of Service). According to the latest recommendations of the ITU-T and based on SMO with queues can be defined by five network characteristics that are indicative of the effectiveness of multi-service NGN/IMS networks and an important indicator of QoS.

AbstractMost people with co-occurring opioid use disorder (OUD) and mental illness do not receive effective medications for treating OUD. To investigate perspectives of adults in a publicly-funded mental health system regarding medications for OUD (MOUD), we conducted semi-structured telephone interviews with 13 adults with OUD (current or previous diagnosis) receiving mental health treatment. Themes that emerged included: perceiving or using MOUDs as a substitute for opioids or a temporary solution to prevent withdrawal symptoms; negative perceptions about methadone/methadone clinics; and viewing MOUD use as “cheating”. Readiness to quit was important for patients to consider MOUDs. All participants were receptive to discussing MOUDs with their mental health providers and welcomed the convenience of receiving care for their mental health and OUD at the same location. In conclusion, clients at publicly-funded mental health clinics support MOUD treatment, signaling a need to expand access and build awareness of MOUDs in these settings.

Mobile health (mHealth) interventions are increasingly used to support community health workers (CHWs) in low-and middle-income countries. As near-peers within their communities, the credibility of CHWs is sometimes questioned—a recognized barrier to their efficacy. Nested within a large, randomized-controlled trial, this qualitative study captured the experiences of South African CHWs, called “Mentor-Mothers,” using tablets and animated videos to promote exclusive breastfeeding. We conducted in-depth telephone interviews with 26 tablet-carrying Mentor-Mothers. We analyzed interview transcripts using a Grounded Theory approach, then developed a theoretical framework, based on an emerging theme, for understanding how tablet technology boosts the perceived credibility of CHWs. Tablet-carrying Mentor-Mothers described an increase in their perceived credibility, which they attributed to overt and signaling effects related to enhanced credibility of (1) their messages, (2) themselves as messengers, and (3) the program employing them. Mobile technology investments in CHWs could enhance their credibility, translating into meaningful investments in the health of under-served communities.

Abstract Background Bladder Cancer (BCa) is a severe genitourinary tract disease with an uncertain pathology. Increasing evidence indicates that the tumor microenvironment plays a decisive role with respect to cancer progression, and that this is driven by tumor cell interactions with stromal components. Tenascin-C (TN-C) is an important extracellular matrix (ECM) component, which has been reported to be involved in other types of cancer, such as breast cancer. The expression of TN-C in BCa tissue has been reported to be positively associated with the BCa pathological grade, yet the presence of urine TN-C is considered as an independent risk factor for BCa. However, the role of TN-C in BCa progression is still unknow. Thus, the object of the present investigation is to determine the role of TN-C in BCa progression and the involved mechanism. Methods In this study, expression of TN-C in BCa tissue of Chinese local people was determined by IHC. Patients corresponding to tumor specimens were flowed up by telephone call to get their prognostic data and analyzed by using SPSS 19.0 statistic package. In vitro mechanistic investigation was demonstrated by QT-qPCR, Western Blot, Plasmid transfection to establishment of high/low TN-C-expression stable cell line, Boyden Chamber Assay, BrdU incorporation, Wound Healing, laser scanning confocal microscopy (LSCM) and ELISA. Results TN-C expression in BCa tissue increases with tumor grade and is an independent risk factor for BCa patient. The in vitro investigation suggested that TN-C enhances BCa cell migration, invasion, proliferation and contributes to the elevated expression of EMT-related markers by activating NF-κB signaling, the mechanism of which involving in syndecan-4. Conclusions Expression of TN-C in BCa tissues of Chinese local people is increased according to tumor grade and is an independent risk factor. TN-C mediates BCa cell malignant behavior via syndecan-4 and NF-κB signaling. Although the mechanisms through which syndecan-4 is associated with the activation of NF-κB signaling are unclear, the data presented herein provide a foundation for future investigations into the role of TN-C in BCa progression.

Abstract Background Glioma is the most common malignant tumor of the central nervous system and is associated with a poor prognosis. This study aimed to explore the function of growth factor receptor-bound protein 10(GRB 10) in glioma. Methods The expression of GRB10 in glioma was determined based on the glioma transcriptome profile downloaded from The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), and Gene Expression Omnibus (GEO) databases. RT-qPCR was performed to detect the expression of GRB10 in tissue samples obtained from 68 glioma patients. The patients were followed up via telephone or in-person outpatient visits to determine survival. Kaplan-Meier survival analyses were used to evaluate the effect of GRB10 on the prognosis of glioma patients. Further, we constructed GRB10 knockdown cell lines were constructed to investigate the effect of GRB10 on glioma. The cell growth, colony formation, cell cycle assay, EdU assay, and tumor formation in xenograft were performed. Results The expression level of GRB10 was positively correlated to the histological grades of gliomas. In addition, Kaplan-Meier survival curves revealed that glioma patients with lower expression of GRB10 had more prolonged survival. The knockdown of GRB10 was shown to inhibit cell proliferation, colony formation, and tumor formation in the xenograft models. Cell cycle assay revealed that the knockdown of GRB10 can inhibit the cells entering the G2/M phase from the S phase. The analysis of GSEA suggests that the expression of GRB10 was positively correlated with the hypoxia and EMT signaling pathway. Conclusions Our data revealed that GRB10 regulated tumorigenesis in glioma and played a vital role in promoting the glioma progression, which indicated that GRB10 could be used as a potential prognostic marker.

AbstractIn SLE, underlying immune dysregulation and immunosuppression may increase the susceptibility to COVID-19 and impair the humoral and adaptive response. We aimed to characterize COVID-19 infection, identifying susceptibility and severity risk factors, assessing the presence of SARS-CoV-2 IgG antibodies and analyzing the cellular response. We established a prospective cohort of lupus patients to estimate the COVID-19 incidence compared to the reference general population. Data were collected via telephone interviews and medical record review. SARS-CoV-2 IgG antibodies were measured cross-sectionally as part of routine surveillance. Longitudinal changes in antibody titers and immunological profile from convalescent COVID-19 patients were evaluated at 6, 12 and 24 week after symptom onset. From immunological studies, PBMCs from convalescent patients were extracted and analyzed by flow cytometry and gene expression analysis. We included 725 patients, identifying 29 with PCR-confirmed COVID-19 infection and 16 with COVID-19-like symptoms without PCR-testing. Of the 29 confirmed cases, 7 had severe disease, 8 required hospital admission (27.6%), 4 intensive care, and 1 died. COVID-19 accumulated incidence was higher in lupus patients. Health care workers and anti-SSA/Ro52 antibody positivity were risk factors for COVID-19 susceptibility, and hypocomplementemia for severity. SARS-CoV-2 IgG antibodies were detected in 8.33% of patients. Three fourths of confirmed COVID-19 cases developed antibodies. High prednisone doses were associated with lack of antibody response. Antibody titers declined over time (39%). Convalescent patients at week 12 after symptom onset displayed a CD8+T cell reduction and predominant Th17 with a mild Th2 response, more pronounced in severe COVID-19 disease. Longitudinal immune response analysis showed a progressive sustained increase in CD8+ T and B memory cells with a decrease of Th17 signaling. Lupus patients are at higher risk of COVID-19 infection and new susceptibility and severity risk factors were identified. Lupus patients were able to mount humoral and cellular responses despite immunosuppressive therapy.

Background: Early brain injury and vasospasm (VSP) in subarachnoid hemorrhage (SAH) are associated with inflammation and release of TNFα, which correlates with poor SAH clinical outcome. TNFα regulates the expression of microRNA (miR) 181b, which mediates NF-κB signaling and is known to exacerbate ischemic stroke in animal models. MiRs have higher stability in biological fluids than peptides and may be candidate clinical biomarkers. We hypothesize that miR-181b is present in SAH CSF and may be associated with SAH outcome. Methods: We prospectively enrolled consecutive SAH subjects, banked serial CSF samples, and evaluated their modified Rankin scores (mRS) via telephone follow-up every 3 months. Poor functional outcome was defined as mRS>2. Angiographic VSP was defined as >50% reduction in caliber of any vessel on post-SAH day 7 cerebral angiogram. In 54 SAH subjects, we compared CSF miR-181b and 26a (as control) by quantitative PCR on post-SAH day 3 with respect to VSP and outcome using Student’s t-test after log-transformation of data with non-normal distribution. Associations were measured using Pearson’s or Spearman’s correlation depending on data distribution. Results: Twenty-seven subjects (50%) developed VSP and 21 (39%) had poor 6-month outcome. MiRs-181b and 26a were consistently measurable in SAH CSF, and miR levels were not associated with Hunt and Hess or Fisher grades. Elevation of CSF miR-181b was associated with poor 6-month outcome in SAH (p=0.04). CSF miR-181b inversely correlated with blood TNFα (r=0.74, p=0.0001). CSF miR-181b was not associated with VSP. CSF miR-26a was not associated with VSP or with clinical outcome in SAH. Conclusion: MiR-181b is present in human CSF after SAH and early elevation of CSF miR-181b is associated with poor 6-month outcome but not with VSP after SAH. Lack of association between control miR-26a and outcome suggests that association between miR-181b and SAH outcome is not due to a non-specific miR surge in more severe cases. Inverse correlation between blood TNFα and CSF miR-181b suggests TNFα may mediate miR-181b release into CSF. Future mechanistic studies on the role of miR-181b in SAH-related brain injury and validation studies in larger cohorts are necessary to understand the role of miR-181b as a SAH biomarker.

IP Telephony, Internet Telephony, Digital Phone or often also called VoIP (Voice Over Internet Protocol) is a technology that allows long-distance voice conversations with the Internet. The increasing number of VoIP users and other IP-based multimedia streaming services naturally raises security issues. Many users are likely to lose their privacy in communication. To overcome this security problem a security system must be implemented. Implementing a security system will use VPN Gateway using SSL and TLS encryption on the VoIP server. The VPN Gateway method is used to build a private network so that only certain users can use the private network. The TLS method is used to secure a user signaling session to the server. From the test results obtained that the VoIP server that uses VPN Gateway and TLS on the server can overcome the attacks e.g., eavesdropping, attacking authentication, teardown session, and denial of service.

Spread spectrum communication is a communication method that deliberately makes the bandwidth of the transmitted waveform larger than would be required to transmit the data over the channel.One of the most encouraging multiplexing techniques for present and forthcoming telecommunications services, such as private communications, ad-hoc wireless communications, third-generation cellular telephony and sensor networks, is the CDMA(code division multiple access) implemented with direct-sequence (DS) signaling. DS-CDMA's benefits include superior operation in multi-path settings, flexibility in channel allocation, enhanced capacity in fading settings, and the capability to share bandwidth with narrowband communication technologies without deteriorating the efficiency of either system. In our work,we are proposing a new know-ba strategy to dismissing interference where originally monitoring signal environment with high precision is called from the library and subsequently based on data that is appropriate for dismissing interference. Various interference scenarios are simulated using computer simulations to show the efficiency of the method.

PurposeThis research focuses on the extent sharing economy transforms employability for women impacted by domestic and reproductive work. The authors explore the experience of mothers, of how digital peer-to-peer (P2P) platforms can affect their self-perceived employability and skills deterioration by unlocking human capital through technology acceptance.Design/methodology/approachThis study adopted a pragmatism-based approach incorporating using a single-case study research design with the Gioia methodology. It utilised a semi-structured telephone survey to collect data to explore the decisions around usage of a newly developed mobile P2P app, aiming to support employability among mothers. Analysis was conducted inductively using thematic analysis and partial least squares structural equation modelling (PLS-SEM).FindingsThe study finds that mothers experience high rates of continued labour market attachment on a casual or part-time basis, difficulty in juggling family and work, and high levels of concern both about future employment/entrepreneurial opportunities and expected stress in balancing dual roles of carer and earner. While mothers are interested in using new sharing economy technologies to reduce skills deterioration and improve signalling, the authors find that there were both technology and non-technology related barriers. These included trust and security, life-stage mismatch, time poverty and limitation of service offerings.Research limitations/implicationsThis research was limited to mothers in one state in Australia and by the case study research design, the measurement model and the self-report nature of the data collection. Hence, the findings may lack generalisability in other contexts. It also limits the ability to make conclusions regarding causality.Originality/valueThis exploratory study contributes to research in the intersection between human resources (HR) and entrepreneurship by illustrating how sharing economy platforms can offer women a means to overcome the issues of signalling and skills deterioration in relation to aspects of human capital theory by developing new skills that may act as positive signals signal to potential employers or investors. Additionally, the social interactions between mothers, through technology adoption, can provide a basis for improving future self-employment or entrepreneurship and employability.

Abstract Aim: To validate the Roth score as a triage tool for detecting hypoxaemia. Backgrounds: The virtual assessment of patients has become increasingly important during the corona virus disease (COVID-19) pandemic, but has limitations as to the evaluation of deteriorating respiratory function. This study presents data on the validity of the Roth score as a triage tool for detecting hypoxaemia remotely in potential COVID-19 patients in general practice. Methods: This cross-sectional validation study was conducted in Dutch general practice. Patients aged ≥18 with suspected or confirmed COVID-19 were asked to rapidly count from 1 to 30 in a single breath. The Roth score involves the highest number counted during exhalation (counting number) and the time taken to reach the maximal count (counting time). Outcome measures were (1) the correlation between both Roth score measurements and simultaneous pulse oximetry (SpO2) on room air and (2) discrimination (c-statistic), sensitivity, specificity and predictive values of the Roth score for detecting hypoxaemia (SpO2 < 95%). Findings: A total of 33 physicians enrolled 105 patients (52.4% female, mean age of 52.6 ± 20.4 years). A positive correlation was found between counting number and SpO2 (rs = 0.44, P < 0.001), whereas only a weak correlation was found between counting time and SpO2 (rs = 0.15, P = 0.14). Discrimination for hypoxaemia was higher for counting number [c-statistic 0.91 (95% CI: 0.85–0.96)] than for counting time [c-statistic 0.77 (95% CI: 0.62–0.93)]. Optimal diagnostic performance was found at a counting number of 20, with a sensitivity of 93.3% (95% CI: 68.1–99.8) and a specificity of 77.8% (95% CI: 67.8–85.9). A counting time of 7 s showed the best sensitivity of 85.7% (95% CI: 57.2–98.2) and specificity of 81.1% (95% CI: 71.5–88.6). Conclusions: A Roth score, with an optimal counting number cut-off value of 20, maybe of added value for signalling hypoxaemia in general practice. Further external validation is warranted before recommending integration in telephone triage.

The Virtual and the Physical The structure of virtual space is a product of the Internet’s geography and technology. Debates around the nature of the virtual — culture, society, economy — often leave out this connection to “fibre”, to where and how we are physically linked to each other. Rather than signaling the “end of geography” (Mitchell 1999), the Internet reinforces its importance with “real world” physical and logical constraints shaping the geography of cyberspace. To contest the nature of the virtual world requires understanding and contesting the nature of the Internet’s architecture in the physical world. The Internet is built on a physical entity – the telecommunications networks that connect computers around the world. In order to participate on the Internet, one needs to connect to these networks. In an information society access to bandwidth determines the haves from the have-nots (Mitchell 1999), and bandwidth depends upon your location and economics. Increasingly, the new generation Internet distributes bandwidth unevenly amongst regions, cities, organizations, and individuals. The speed, type, size and quality of these networks determine the level and nature of participation available to communities. Yet these types of choices, the physical and technical aspects of the network, are the ones least understood, contested and linked to “real world” realities. The Technical is the Political Recently, the US government proposed a Total Information Awareness surveillance system for all digital communications nationally. While technically unworkable on multiple fronts, many believed that the architecture of the Internet simply prevented such data collection, because no physical access points exist through which all data flows. In reality, North America does have central access points – six to be exact – through which all data moves because it is physically impossible to create redundant systems. This simple factor of geography potentially shapes policies on speech, privacy, terrorism, and government-business relations to name just a few. These are not new issues or challenges, but merely new technologies. The geography of infrastructure – from electricity, train and telephone networks to the architectures of freeways, cities and buildings – has always been as much social and political as technical. The technology and the social norms embedded in the network geography (Eischen, 2002) are central to the nature of cyberspace. We may wish for a utopian vision, but the hidden social assumptions in mundane ‘engineering’ questions like the location of fibre or bandwidth quality will shape virtual world. The Changing Landscape of the Internet The original Internet infrastructure is being redesigned and rebuilt. The massive fibre-optic networks of the Internet backbones have been upgraded, and broadband access technologies – cable modem, Digital Subscriber Line (DSL) and now wireless Wi-Fi – are being installed closer to homes and businesses. New network technologies and protocols enable the network to serve up data even faster than before. However, the next generation Internet architecture is quite different from the popular utopian vision described above. The Internet is being restructured as an entertainment and commerce medium, driven by the convergence of telecommunications technologies and commercialization. It is moving towards a broadcast model where individual consumers have access to less upstream bandwidth than downstream, with the symmetry of vendor and customer redesigned and built to favor content depending on who provides, requests and receives content. This Internet infrastructure has both physical and logical components – the telecommunications networks that comprise the physical infrastructure and the protocols that comprise the logical infrastructure of the software that runs the Internet. We are in the process of partitioning this infrastructure, both physical and logical, into information conduits of different speeds and sizes. Access to these conduits depends on who and where you are. These emerging Internet infrastructure technologies – Broadband Access Networks, Caching and Content Delivery Networks, Quality of Service and Policy Protocols – are shaped by geographical, economic and social factors in their development, deployment and use. The Geography of Broadband These new broadband networks are being deployed initially in more privileged, densely populated communities in primary cities and their wealthy suburbs (Graham, 2000). Even though many have touted the potential of Wi-Fi networks to bring broadband to underserved areas, initial mappings of wireless deployment show correlation between income and location of hotspots (NYCWireless, 2003). Equally important, the most commonly deployed broadband technologies, cable modem and ADSL, follow a broadcast model by offering more downstream bandwidth than upstream bandwidth. Some cable companies limit upstream bandwidth even further to 256 Kbps in order to discourage subscribers from setting up home servers. The asymmetry of bandwidth leads to asymmetry of information flows where corporations produce information and users content. Internet Infrastructure: Toll Roads and the Priority of Packets The Internet originally was designed around ‘best effort’ service: data flows through the networks as packets, and all packets are treated equally. The TCP/IP protocols that comprise the Internet’s logical infrastructure (Lessig, 101) govern how data is transferred across the physical networks. In the Internet’s original design, each packet is routed to the best path known, with the transport quality level dependent on network conditions. However, network congestion and differing content locations lead to inconsistent levels of quality. In order to overcome Internet “bottlenecks”, technologies such as content caching and Quality of Service (QoS) protocols have been developed that allow large corporate customers to bypass the public infrastructure, partitioning the Internet into publicly and privately accessible data conduits or throughways. Since access is based on payment, these private throughways can be thought of as the new toll roads of the Internet. Companies such as Akamai are deploying private ‘content delivery’ networks. These networks replicate and store content in geographically dispersed servers close to the end users, reducing the distance content data needs to traverse. Large content providers pay these companies to store and serve their content on these networks. Internet Service Providers (ISPs) offer similar services for internal or hosted content. The Internet’s physical infrastructure consists of a system of interconnected networks. The major ISPs’ networks interconnect at Network Access Point (NAPs) the major intersections of the Internet backbone. Congestion at these public intersection points has resulted in InterNAP building and deploying private network access points (P-NAPs). Akamai content delivery network (Akamai, 2000) and InterNAP’s P-NAPs (InterNAP, 2000) deployment maps reveal a deployment of private infrastructure to a select group of highly-connected U.S. cities (Moss & Townsend, 2000), furthering the advantage these ‘global cities’ (Graham, 1999) have over other cities and regions. QoS protocols allow ISPs to define differing levels of service by providing preferential treatment to some amount of the network traffic. Smart routers, or policy routers, enable network providers to define policies for data packet treatment. The routers can discriminate between and prioritize the handling of packets based on destination, source, the ISP, data content type, etc. Such protocols and policies represent a departure from the original peer-to-peer architecture of data equality with ‘best-effort’. The ability to discriminate and prioritize data traffic is being built into the system, with economic and even political factors able to shape the way packets and content flow through the network. For example, during the war on Iraq, Akamai Technologies canceled its service contract with the Arabic news service Al Jazeera (CNET, 2003). Technology, Choices and Values To address the social choices underpinning seemingly benign technical choices of the next generation Internet, we need to understand the economic, geographic and social factors guiding choices about its design and deployment. Just as the current architecture of the Internet reflects the values of its original creators, this next generation Internet will reflect our choices and our values. The reality is that decisions with very long-term impacts will be made with or without debate. If any utopian vision of the Internet is to survive, it is crucial to embed the new architectures with specific values by asking difficult questions with no pre-defined or easy answers. These are questions that require social debate and consensus. Is the Internet fundamentally a public or private space? Who will have access? What information and whose information will be accessible? Which values and whose values should form the basis of the new infrastructure? Should the construction be subject to market forces alone or should ideas of social equity and fairness be embedded in the technology? Technologists, policy makers (at both national and local levels), researchers and the general public all have a part in determining the answers to these questions. Policymakers need to link future competition and innovation with equitable access for all citizens. Urban planners and local governments need to link infrastructure, economic sustainability and equity through public and public-private investments – especially in traditionally marginalized areas. Researchers need to continue mapping the complex interactions of investment in and deployment of infrastructure across the disciplines of economics, technology and urban planning. Technologists need to consider the societal implications and inform the policy debates of the technologies they build. Communities need to link technical issues with local ramifications, contesting and advocating with policymakers and corporations. The ultimate geography of cyberspace will reflect the geography of fibre. Understanding and contesting the present and future reality requires linking mundane technical questions with the questions of values in exactly these wider social and political debates. Works Cited Akamai. See <http://www.akamai.com/service/network.php> Eischen, Kyle. ‘The Social Impact of Informational Production: Software Development as an Informational Practice’. Center for Global, International and Regional Studies Working Paper #2002-1. 2002. UC Santa Cruz. <http://cgirs.ucsc.edu/publications/workingpapers/> Graham, Stephen. “Global Grids of Glass: On Global Cities, Telecommunications and Planetary Urban Networks.” Urban Studies. 1999. 36 (5-6). Graham, Stephen. “Constructing Premium Network Spaces: Reflections on Infrastructure Networks and Contemporary Urban Development.” International Journal of Urban and Regional Research. 2000. 24(1) March. InterNAP. See <http://www.internap.com/html/news_05022000.htm> Junnarkar, Sandeep. “Akamai ends Al-Jazeera server support”, CNET News.com, April 4, 2003. See <http://news.com.com/1200-1035-995546.php> Lessig, Lawrence. Code and Other Laws of Cyberspace. New York: Basic Books, 1999. Mitchell, William. City of Bits. Cambridge, MA: MIT Press, 1999. Mosss, Mitchell L. and Anthony M. Townsend. “The Internet Backbone and the American Metropolis.” The Information Society Journal. 16(1): 35-47. Online at: <http://www.informationcity.org/research/internet-backbone-am... ...erican-metropolis/index.htm> Public Internet Project. “802.11b Survey of NYC.” <http://www.publicinternetproject.org/> Links http://cgirs.ucsc.edu/publications/workingpapers/ http://news.com.com/1200-1035-995546.html http://www.akamai.com/service/network.html http://www.informationcity.org/research/internet-backbone-american-metropolis/index.htm http://www.internap.com/html/news_05022000.htm http://www.publicinternetproject.org/ Citation reference for this article Substitute your date of access for Dn Month Year etc... MLA Style Eischen, Emy Tseng & Kyle. "The Geography of Cyberspace" M/C: A Journal of Media and Culture< http://www.media-culture.org.au/0308/03-geography.php>. APA Style Eischen, E. T. &. K. (2003, Aug 26). The Geography of Cyberspace. M/C: A Journal of Media and Culture, 6,< http://www.media-culture.org.au/0308/03-geography.php>