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The development of Directional Medium Access Control (DMAC) strategies that allow to enhance the limitations due to the use of omnidirectional antennas in Mobile ad Hoc Networks (MANET), introduces several issues that need to be properly addressed such as the Deafness problem. The use of Smart Antenna Systems (SAS) along with Directional Request To Send (DRTS) and Directional Clear To Send (DCTS) could be not sufficient to mitigate the Deafness. In this regard, a sectorized antenna approach together with a frame scheduling mechanism can improve the overall MAC performance while limiting the Deafness; however, the employment of scheduling algorithms without priority such as the Round Robin could limit the network performance especially in terms of Packet Delivery Ratio (PDR) and fairness. For this reason, we propose two approaches: the A-MSDU (Aggregation MAC Service Data Unit) MAC and a WRR (Weighted Round Robin) MAC that could allow to overcome the limitations of the Round Robin scheme applied at MAC layer in order to have an high efficiency in the overall resource allocation. More specifically, obtained results show that, through the use of frame aggregation, it is possible to considerably reduce issues implied by Round Robin such as time slice and network overhead; WRR approach, instead, is able to enhance the overall network fairness by reducing the number of collisions provided by a directional MAC based on Round Robin scheduling; this aspect translates into higher PDR performance compared to Round Robin approach. [ABSTRACT FROM AUTHOR]

Fungal sectorization is a complex trait that is still not fully understood. The unique phenotypic changes in sporadic sectorization in mutants of CpBck1, a mitogen-activated protein kinase kinase kinase (MAPKKK) gene, and CpSlt2, a mitogenactivated protein kinase (MAPK) gene, in the cell wall integrity pathway of the chestnut blight fungus Cryphonectria parasitica have been previously studied. Although several environmental and physiological factors cause this sectoring phenotype, genetic variants can also impact this complex morphogenesis. Therefore, RNA sequencing analysis was employed to identify candidate genes associated with sectorization traits and understand the genetic mechanism of this phenotype. Transcriptomic analysis of CpBck1 and CpSlt2 mutants and their sectored progeny strains revealed a number of differentially expressed genes (DEGs) related to various cellular processes. Approximately 70% of DEGs were common between the wild-type and each of CpBck1 and CpSlt2 mutants, indicating that CpBck1 and CpSlt2 are components of the same MAPK pathway, but each component governs specific sets of genes. Functional description of the DEGs between the parental mutants and their sectored progenies revealed several key pathways, including the biosynthesis of secondary metabolites, translation, amino acid metabolism, and carbohydrate metabolism; among these, pathways for secondary metabolism and translation appeared to be the most common pathway. The results of this comparative study provide a better understanding of the genetic regulation of sector formation and suggest that complex several regulatory pathways result in interplays between secondary metabolites and morphogenesis. [ABSTRACT FROM AUTHOR]

Most water supply utilities in the world need to deal with daily operations of their systems while at the same time they are required to increase their efficiency. One way to increase the efficiency of the system is to divide the water distribution network into smaller subsystems called sectors. This article presents a new sectorization approach, which has been developed as part of the European FP7 research project ICeWater, focused on increasing energy efficiency. The approach is based on the combination of graph theory and multi-objective optimization applied to the system of Milan (Italy). Most existing approaches for sectorization deal with gravity sources. The methodology presented here has been applied to a system with 26 pump stations, which is an innovation and a step forward for other utilities facing similar challenges. The application of sectorization to the network of Milan has the advantage of allowing to fix the number of sectors and enabling the exploration of multiple scenarios of system operation. [ABSTRACT FROM AUTHOR]

Sectorization is a process aimed at efficiently managing Water Supply Networks (WSNs). There are many large WSNs where the number of sectors into which they might be subdivided is initially unknown. Our method uses concepts derived from the Social Network Theory (SNT) such as centrality and community detection to obtain such subdivisions. The output is then evaluated through energy criteria. This methodology entails two very important benefits over other methods previously proposed. Firstly, it is applicable to WSNs depending on a network trunk and, secondly, it considers the technical know-how of the staff of the water utility. [ABSTRACT FROM AUTHOR]

Complex and large size hydraulic systems require the division into modules in order to simplify the analysis and the management tasks. In complex network theory, modularity index was proposed as a measure of the strength of the network division into communities, i.e. modules. Nevertheless, modularity index needs to be revised considering the specificity of the hydraulic systems as infrastructure systems. Accordingly, the classic modularity index is firstly presented and, then, tailored and modified for water distribution systems. Furthermore, a new modularity based index is proposed in order to resolve resolution limit of the original metric. [ABSTRACT FROM AUTHOR]

Abstract: The introduction of cyanide with a backflow attack into a water system was studied. The recent development of techniques for water network sectorization, aimed to improve the management of water systems, represents also an efficient way to protect networks from intentional contamination. The possibility of closing gate valves by a remote control system to create an i-DMA (isolated District Meter Area) can reduce the risk of contamination and thus the extent of damage of a terroristic attack. The study proposes a novel technique for designing i-DMAs compatible with hydraulic performance and optimized for water network protection. [Copyright &y& Elsevier]

Highlights: [•] A conflict risk assessment model was developed for airspace operational and current day planning. [•] The risk is defined as the product of conflict probability and conflict frequency. [•] The risk is assumed to be a random variable. [•] It is designed to be used as a decision support tool for air traffic managers. [Copyright &y& Elsevier]

Abstract: In this paper, we investigate the integrated network planning for telecommunications system, which considers adaptive sectorization and a hybrid F/CDMA scheme jointly under quality of service (QoS) constraints. The problem is formulated as a combinatorial optimization formulation in terms of minimizing the cost. We also investigate the viability of using Lagrangean relaxation (LR) to solve the problem. With regard to the computational results, the cost of considering network error states in the planning stage is 45% more than that of non-error. The proposed LR approach outperforms a simple algorithm with a cost improvement of 60%. In addition, the link constraint is more important to the total cost than the node constraint. Given a link constraint, the cost is affected more significantly by a decreasing threshold than by an increasing threshold. The proposed model is not only a valuable reference for network planning in a new field (e.g., a desert scenario), but also fits the planning requirements when some equipment pre-exists (an embedded scenario). We assign constant values to several decision variables, so the model is adaptable to various scenarios. [Copyright &y& Elsevier]

Abstract: Community mental health teams (CMHTs) have evolved alongside the downsizing of mental hospitals. They originated in mental health services in the UK and France in the 1950s and 60s. Generic CMHTs provide assessment and treatment for the population of a defined sector (usually stratified by age: child, adult and old age), who are referred by GPs or other health professionals. Despite considerable variation there are regular features of such teams – in particular their approach to multidisciplinary working management and caseloads – which are broadly similar and are outlined here. Common issues of CMHTs addressed in this contribution include leadership, size, the mix of disciplines and the management of multiple lines of authority. As secondary care teams, CMHTs generally need to be particularly clear about liaison and relationships with their referring GPs and arrangements around shared responsibilities with social services. Despite attempts by governments it is neither possible nor sensible to impose a rigid model of working across all circumstances. It is the need for clarity around these principles of liaison and shared working responsibilities that is essential and fixed. CMHTs have increasingly adopted standardized approaches to patient management such as the Care Programme Approach (CPA), fixed caseloads and the development of referral and discharge protocols. They remain responsive and complex organizations that have endured despite several attempts to supplant them and despite the challenges and frustrations that they can present to those who work in them. [Copyright &y& Elsevier]

Authors make a brief history of the french sectorization system. They show how this mental health policy was continuously carried out since 1960, creating the conditions of a progressive deinstitutionalization. They compare the french sector model as it was conceived in 1960, with the Assertive Community Treatment (ACT) model described in the United States by Stein and Test. Authors also describe how the sector model was able to adapt itself to the changes in needs for psychiatric care in France, particularly in the fields of emergency and liaison psychiatry. [Copyright &y& Elsevier]

Regionalization is of great practical importance, being applied in fields ranging from air space to water distribution. Canada has one of the highest waste generation rates in the world, disposing an average of 694.4 kg/cap in 2018. Waste management costed Canadians about CAD $3.3 billion in 2016, with collection and transportation making up 41.3% of this expenditure. Regionalized waste management systems are becoming popular in Canada and around the world; and design and optimization of regions is vital. Different spatial statistics are used to optimize 3 sub-regions in Saskatchewan (Regina, Leinan, and Beatty). Centroidal Voronoi Tessellation is generally the most efficient method. When the ratio of populated places to road length is low (0.010), 'median center' better optimized populated places in each sub-region. Computational demand was highest in Beatty (19.0 iterations), followed by Regina (9.67 iterations) and Leinan (5.33 iterations) indicating a trade-off between the number of sub-regions, computational efficiency, and optimized percent standard deviation. A strong linear relationship is observed in some cases between percent SD of optimized parameters and standard deviation of area, indicating the importance of relative size in optimization. In Regina, Median center (rank = 2) was ranked higher than mean center (rank = 3), while the opposite was true in Beatty. Feature distribution within regions and different spatial statistics in the algorithm should be explored. This work is of practical importance in waste management and other fields where region development is important. [ABSTRACT FROM AUTHOR]

Electrode sectorization is an important design principle for large area GEM based detectors. It reduces the energy of discharges and permits to disconnect defective or shorted sectors, but induces a local signal distortion and a potential efficiency loss. We implemented and evaluated a new design approach for the insulating gaps between electrode sectors, to minimize or mitigate distortions and dead regions. By preserving the hole pattern of GEMs even in the insulating region between electrode sectors, the response of the detector in these regions was partly recovered resulting in reduced distortions. Single-side sectored GEMs were optically read out to study the influence of different sectorization patterns. Recorded images show a clear improvement with full holes both aligned with the rows and with a random alignment as compared to the traditional blank insulating strip between sectors. A sectored GEM manufactured on a substrate coated with a resistive DLC layer was evaluated and shown to minimize distortions. The investigated sectorization patterns provide a way of recovering signals in the insulating or resistive regions between sectors in GEM-based detectors. [ABSTRACT FROM AUTHOR]