A Quasi-Omnidirectional Antenna for Modern Wireless Communication Gadgets

A compact, planar, wideband antenna designed by modifying the coplanar waveguide is presented in this letter. The proposed antenna finds a wide range of applications including advanced wireless systems (AWS), DCS-1800, DCS-1900/PCS/PHS, WiBro, BlueTooth/WLAN/WiBree/ZigBee, DMB, Global Star Satellite Phones, and digital cordless phones. Wide bandwidth > 75% centered at 2.50 GHz, quasi-omnidirectional radiation coverage along with moderate gain and efficiency are the salient features of the antenna. A prototype fabricated on a substrate with dielectric constant 4.4 and thickness 1.6 mm occupies an area of (31times 64) mm2. Details of antenna design and discussions on the effect of various antenna parameters on the radiation characteristics are presented.

Water quality variation and nutrient characteristics of Kodungallur-Azhikode Estuary, Kerala, India

Present study focussed on the water quality status in relation to various anthropogenic activities in the Kodungallur- Azhikode Estuary (KAE). Average depth of the estuary was 3.6 ± 0.2 m with maximum of 4.3 ± 0.4 m in the estuarine mouth. Dissolved oxygen showed an average of 5.1±1 mg/l in the water column, whereas the highest BOD value was noticed during monsoon period (3.1 ± 0.8 mg/l) which could be due to high organic enrichment in the water column. pH displayed slightly alkaline condition in most of the stations and it varied from 7.2 ± 0.5 in Station 7 to 7.5 ± 0.5 in Station 1. Salinity in the estuary displayed mixo-mesohaline nature with clear vertical stratification. High river discharge could have resulted in nutrients and silt loading into the estuary, which makes a highly turbid water column particularly during the monsoon period, which limits light penetration and subsequent primary productivity. Turbidity in the water column showed an average of 20.2 ± 15.8 NTU. Estuary was nitrogen limited during post and pre monsoon periods. Nitrate-nitrogen content in the estuarine water gave negative correlation with ammonia.

Informal communication networks and the diffusion of innovations in UK construction projects: A research design

The UK industry has been criticised for being slow to adopt construction process innovations. Research shows that the idiosyncrasies of participants, their roles in the system and the contextual differences between sections of the industry make this a highly complex problem. There is considerable evidence that informal social networks play a key role in diffusion of innovations. The aim is to identify informal communication networks of project participants and the role these play in the diffusion of construction innovations. The characteristics of this network will be analysed in order to understand how they can be used to accelerate innovation diffusion within and between projects. Social Network Analysis is used to determine informal communication routes. Control and experiment case study projects are used within two different organizations. This allows informal communication routes concerning innovations to be mapped, whilst testing if the informal routes can facilitate diffusion. Analysis will focus upon understanding the combination of informal strong and weak ties, and how these impede or facilitate the diffusion of the innovation. Initial work suggests the presence of an informal communication network. Actors within this informal network, and the organization's management are unaware of its' existence and their informal roles within it. Thus, the network remains an untapped medium regarding innovation diffusion. It is proposed that successful innovation diffusion is dependent upon understanding informal strong and weak ties, at project, organization and industry level.

Conversations around homework: links to parental mental health, family characteristics and child psychological functioning

Parents are increasingly expected to supplement their children's school-based learning by providing support for children's homework. However, parents' capacities to provide such support may vary and may be limited by the experience of depression. This may have implications for child development. In the course of a prospective, longitudinal study of children of postnatally depressed and healthy mothers, we observed mothers (N = 88) and fathers (N = 78) at home during maths homework interactions with their 8-year-old children. The quality of parental communication was rated and analysed in relation to child functioning. The quality of communication of each of the parents was related to their mental state, social class and IQ. While postnatal depression was not directly related to child development, there was some evidence of the influence of maternal depression occurring in the child's school years. Different aspects of parental communication with the child showed specific associations with different child outcomes, over and above the influence of family characteristics. In particular, child school attainment and IQ were associated with parental strategies to encourage representational thinking and mastery motivation, whereas child behavioural adjustment at school and self-esteem were linked to the degree of parental emotional support and low levels of coercion. Notably, the influence of maternal homework support was more strongly related to child outcome than was paternal support, a pattern reflected in mothers' greater involvement in children's schools and school-related activities. Some parents may need guidance in how to support their children's homework if it is to be of benefit to child functioning.

Validation of the social communication questionnaire in a population cohort of children with autism spectrum disorders

Objective: To examine the properties of the Social Communication Questionnaire (SCQ) in a population cohort of children with autism spectrum disorders (ASDs) and in the general population, Method: SCQ data were collected from three samples: the Special Needs and Autism Project (SNAP) cohort of 9- to 10-year-old children with special educational needs with and without ASD and two similar but separate age groups of children from the general population (n = 411 and n = 247). Diagnostic assessments were completed on a stratified subsample (n = 255) of the special educational needs group. A sample-weighting procedure enabled us to estimate characteristics of the SCQ in the total ASD population. Diagnostic status of cases in the general population samples were extracted from child health records. Results: The SCQ showed strong discrimination between ASD and non-ASD cases (sensitivity 0.88, specificity 0.72) and between autism and nonautism cases (sensitivity 0.90, specificity 0.86). Findings were not affected by child IQ or parental education. In the general population samples between 4% and 5% of children scored above the ASD cutoff including 1.5% who scored above the autism cutoff. Although many of these high-scoring children had an ASD diagnosis, almost all (similar to 90%) of them had a diagnosed neurodevelopmental disorder. Conclusions: This study confirms the utility of the SCQ as a,first-level screen for ASD in at-risk samples of school-age children.

Non-uniform data distribution for communication-efficient parallel clustering

Global communicationrequirements andloadimbalanceof someparalleldataminingalgorithms arethe major obstacles to exploitthe computational power of large-scale systems. This work investigates how non-uniform data distributions can be exploited to remove the global communication requirement and to reduce the communication costin parallel data mining algorithms and, in particular, in the k-means algorithm for cluster analysis. In the straightforward parallel formulation of the k-means algorithm, data and computation loads are uniformly distributed over the processing nodes. This approach has excellent load balancing characteristics that may suggest it could scale up to large and extreme-scale parallel computing systems. However, at each iteration step the algorithm requires a global reduction operationwhichhinders thescalabilityoftheapproach.Thisworkstudiesadifferentparallelformulation of the algorithm where the requirement of global communication is removed, while maintaining the same deterministic nature ofthe centralised algorithm. The proposed approach exploits a non-uniform data distribution which can be either found in real-world distributed applications or can be induced by means ofmulti-dimensional binary searchtrees. The approachcanalso be extended to accommodate an approximation error which allows a further reduction ofthe communication costs. The effectiveness of the exact and approximate methods has been tested in a parallel computing system with 64 processors and in simulations with 1024 processing element

New opportunities for secure communication networks using shaped femtosecond laser pulses inducing filamentation processes in the atmosphere

The current study discusses new opportunities for secure ground to satellite communications using shaped femtosecond pulses that induce spatial hole burning in the atmosphere for efficient communications with data encoded within super-continua generated by femtosecond pulses. Refractive index variation across the different layers in the atmosphere may be modelled using assumptions that the upper strata of the atmosphere and troposphere behaving as layered composite amorphous dielectric networks composed of resistors and capacitors with different time constants across each layer. Input-output expressions of the dynamics of the networks in the frequency domain provide the transmission characteristics of the propagation medium. Femtosecond pulse shaping may be used to optimize the pulse phase-front and spectral composition across the different layers in the atmosphere. A generic procedure based on evolutionary algorithms to perform the pulse shaping is proposed. In contrast to alternative procedures that would require ab initio modelling and calculations of the propagation constant for the pulse through the atmosphere, the proposed approach is adaptive, compensating for refractive index variations along the column of air between the transmitter and receiver.

Inter-plant communication through mycorrhizal networks mediates complex adaptive behaviour in plant communities

Adaptive behaviour of plants, including rapid changes in physiology, gene regulation and defence response, can be altered when linked to neighbouring plants by a mycorrhizal network (MN). Mechanisms underlying the behavioural changes include mycorrhizal fungal colonization by the MN or interplant communication via transfer of nutrients, defence signals or allelochemicals. We focus this review on our new findings in ectomycorrhizal ecosystems, and also review recent advances in arbuscular mycorrhizal systems. We have found that the behavioural changes in ectomycorrhizal plants depend on environmental cues, the identity of the plant neighbour and the characteristics of the MN. The hierarchical integration of this phenomenon with other biological networks at broader scales in forest ecosystems, and the consequences we have observed when it is interrupted, indicate that underground ‘tree talk’ is a foundational process in the complex adaptive nature of forest ecosystems.

Language and interaction in online asynchronous communication in university level English courses

Interaction involves people communicating and reacting to each other. This process is key to the study of discourse, but it is not easy to study systematically how interaction takes place in a specific communicative event, or how it is typically performed over a series of repeated communicative events. However, with a written record of the interaction, it becomes possible to study the process in some detail. This thesis investigates interaction through asynchronous written discussion forums in a computer-mediated learning environment. In particular, this study investigates pragmatic aspects of the communicative event which the asynchronous online discussions comprise. The first case study examines response patterns to messages by looking at the content of initial messages and responses, in order to determine the extent to which characteristics of the messages themselves or other situational factors affect the interaction. The second study examines in what ways participants use a range of discourse devices, including formulaic politeness, humour and supportive feedback as community building strategies in the interaction. The third study investigates the role of the subject line of messages in the interaction, for example by examining how participants choose different types of subject lines for different types of messages. The fourth study examines to what extent features serving a deictic function are drawn on in the interaction and then compares the findings to both oral conversation and formal academic discourse. The overall findings show a complex communicative situation shaped by the medium itself, type of activity, the academic discipline and topic of discussion and by the social and cultural aspects of tertiary education in an online learning environment. In addition, the findings may also provide evidence of learning.  

Nurse-patient communication while performing home dialysis: The patients' perceptions

This study aimed at describing patients' perception of their communication with nurses when performing home dialysis. Data were collected from interviews guided by the question: What is communication like, between you and nurses, during home dialysis treatment? Results show participants' perception of treatment during home peritoneal dialysis [Continuous ambulatory peritoneal dialysis (CAPD)]; relationship with nurses and family and the effects of treatment on one's existence. Patients can be self-caring and they learn to value the autonomy in their own care. However, some are unable to assume the responsibility for self-care. It was discovered that the connotation of inspection that some participants attributed to the nurse's visits, led to an alienation from the education process in the CAPD education. Findings suggest that effective communication and the development of the relationship of a working partnership with patients is crucial. Improvement in the nurses' communication, aiming at adapting it to the characteristics, limitations and specific needs of each patient, is significant for achieving better outcomes. © 2010 European Dialysis and Transplant Nurses Association/European Renal Care Association.

Characteristics of households with ICTs in Latin America and the Caribbean

Includes bibliography

Characteristics of fricatives consonants orthography in Brazilian children

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

General biochemical and immunological characteristics of the venom from Peruvian scorpion Hadruroides lunatus

This communication describes the general biochemical properties and some immunological characteristics of the venom from the Peruvian scorpion Hadruroides lunatus, which is the most medically relevant species in Peru. The soluble venom of this scorpion is toxic to mice, the LD50 determined was 0.1 mg/kg and 21.55 mg/kg when the venom was injected intracranial or intraperitoneally, respectively. The soluble venom displayed proteolytic, hyaluronidasic, phospholipasic and cardiotoxic activities. High performance liquid chromatography of the soluble venom resulted in the separation of 20 fractions. Two peptides with phospholipasic activity were isolated to homogeneity and their molecular masses determined by mass spectrometry (MALDI TOF). Anti-H. lunatus venom sera were produced in rabbits. Western blotting analysis showed that most of the protein content of this venom is immunogenic. H. lunatus anti-venom displayed consistent cross-reactivity with venom antigens from the new World-scorpions Tityus serrulatus and Centruroides sculpturatus venoms; however, a weaker reactivity was observed against the venom antigens from the old World-scorpion Androctonus australis Hector. (C) 2012 Elsevier Ltd. All rights reserved.

Cooperative communication and distributed detection in wireless sensor networks

Recent progress in microelectronic and wireless communications have enabled the development of low cost, low power, multifunctional sensors, which has allowed the birth of new type of networks named wireless sensor networks (WSNs). The main features of such networks are: the nodes can be positioned randomly over a given field with a high density; each node operates both like sensor (for collection of environmental data) as well as transceiver (for transmission of information to the data retrieval); the nodes have limited energy resources. The use of wireless communications and the small size of nodes, make this type of networks suitable for a large number of applications. For example, sensor nodes can be used to monitor a high risk region, as near a volcano; in a hospital they could be used to monitor physical conditions of patients. For each of these possible application scenarios, it is necessary to guarantee a trade-off between energy consumptions and communication reliability. The thesis investigates the use of WSNs in two possible scenarios and for each of them suggests a solution that permits to solve relating problems considering the trade-off introduced. The first scenario considers a network with a high number of nodes deployed in a given geographical area without detailed planning that have to transmit data toward a coordinator node, named sink, that we assume to be located onboard an unmanned aerial vehicle (UAV). This is a practical example of reachback communication, characterized by the high density of nodes that have to transmit data reliably and efficiently towards a far receiver. It is considered that each node transmits a common shared message directly to the receiver onboard the UAV whenever it receives a broadcast message (triggered for example by the vehicle). We assume that the communication channels between the local nodes and the receiver are subject to fading and noise. The receiver onboard the UAV must be able to fuse the weak and noisy signals in a coherent way to receive the data reliably. It is proposed a cooperative diversity concept as an effective solution to the reachback problem. In particular, it is considered a spread spectrum (SS) transmission scheme in conjunction with a fusion center that can exploit cooperative diversity, without requiring stringent synchronization between nodes. The idea consists of simultaneous transmission of the common message among the nodes and a Rake reception at the fusion center. The proposed solution is mainly motivated by two goals: the necessity to have simple nodes (to this aim we move the computational complexity to the receiver onboard the UAV), and the importance to guarantee high levels of energy efficiency of the network, thus increasing the network lifetime. The proposed scheme is analyzed in order to better understand the effectiveness of the approach presented. The performance metrics considered are both the theoretical limit on the maximum amount of data that can be collected by the receiver, as well as the error probability with a given modulation scheme. Since we deal with a WSN, both of these performance are evaluated taking into consideration the energy efficiency of the network. The second scenario considers the use of a chain network for the detection of fires by using nodes that have a double function of sensors and routers. The first one is relative to the monitoring of a temperature parameter that allows to take a local binary decision of target (fire) absent/present. The second one considers that each node receives a decision made by the previous node of the chain, compares this with that deriving by the observation of the phenomenon, and transmits the final result to the next node. The chain ends at the sink node that transmits the received decision to the user. In this network the goals are to limit throughput in each sensor-to-sensor link and minimize probability of error at the last stage of the chain. This is a typical scenario of distributed detection. To obtain good performance it is necessary to define some fusion rules for each node to summarize local observations and decisions of the previous nodes, to get a final decision that it is transmitted to the next node. WSNs have been studied also under a practical point of view, describing both the main characteristics of IEEE802:15:4 standard and two commercial WSN platforms. By using a commercial WSN platform it is realized an agricultural application that has been tested in a six months on-field experimentation.

Coping With a Family Member's Death: Parenting, Religiosity, and Parent-Child Communication

The present study had three major aims. First, this study was a basic descriptive exploration of the frequency and nature of parent-child communication about death. Second, this study conducted a quantitative analysis to identify predictors of communication and bereaved children¿s emotional and behavioral problems. Third, this study was also a qualitative analysis of parents¿ descriptions of how religious views shape conversations about death and how conversations are beneficial. Based on prior research, it was predicted that positive child outcomes would be associated with parental warmth, religiosity, adaptive coping, positive religious coping, and frequent parent-child communication about death. Conversely, it was predicted that negative child outcomes would be associated with parental psychological control, maladaptive coping, negative religious coping, and less frequent parent-child communication about death. Additionally, it was hypothesized that parents¿ religious and spiritual views would shape parent-child communication about death, and parents would describe numerous benefits of discussing death with children. Parents completed a series of survey measures assessing their religiosity, coping strategies, parent-child communication about death, and their children¿s emotional and behavioral symptoms. Almost 80% of parent-child dyads discussed death at least once a week, and children initiated approximately half of these conversations. Parent-child communication about death was predicted by parents¿ warmth toward and acceptance of their children and inversely predicted by children¿s hyperactivity and social problem solving. Higher levels of children¿s social problem solving could predict lower frequency of parent-child communication about death if children were holding frequent, meaningful, and comforting conversations with friends and other adults. Higher levels of parents¿ psychological control predicted more emotional and behavioral problems in the child. Parents¿ adaptive coping had significant relationships with all of the dimensions of parent-child communication about death. Qualitative analyses revealed that parents perceived their religious beliefs as shaping conversations about death and grief as an individualized journey. A majority of parents described the emotional, social, and intellectual benefits of holding parent-child conversations about death. This study contributes to the literature by further describing parent-child communication about death, identifying its predictors, and investigating parents¿ religiosity and coping strategies in relation to child well-being. Overall, this study revealed the importance of assessing global parenting characteristics (i.e., warmth/acceptance and psychological control) when examining parent-child relationships and communication about death. Furthermore, this unique study illustrates the value of qualitative data when examining parent-child communication about death and religiosity.