28 GHz Taylor Feed Network for Sidelobe Level Reduction in 5G Phased Array Antennas

This paper presents a design procedure for a phased array feed network. The procedure is validated by designing and fabricating a set of 28 GHz 8‐element beam steerable antennas. Within the feed, a Taylor n‐bar amplitude taper is implemented using unequal power dividers. At boresight, the taper reduced the sidelobe level by 2.84 dB to −15.2 dB. Beam steering from 0° to 48° is achieved using meanders. An empirical formula for the meander widths is proposed, enabling independent control of amplitude and phase. Empirical formulae for the initial parameters of the unequal dividers are also proposed. The wide transmission lines in this feed network are compatible with low‐cost PCB fabrication techniques

A Complete Year of User Retrieval Sessions in a Social Sciences Academic Search Engine

In this paper, we present an open data set extracted from the transaction log of the social sciences academic search engine sowiport. The data set includes a filtered set of 484,449 retrieval sessions which have been carried out by sowiport users in the period from April 2014 to April 2015. We propose a description of interactions performed by the academic search engine users that can be used in different applications such as result ranking improvement, user modeling, query reformulation analysis, search pattern recognition.Comment: 6 pages, 2 figures, accepted short paper at the 21st International Conference on Theory and Practice of Digital Libraries (TPDL 2017

Cascaded Fresnel Lens Antenna for Scan Loss Mitigation in Millimeter-Wave Access Points

Millimeter wave lens antennas will be essential for future wireless access. Conventionally, they increase the gain in the boresight direction only. In this paper, cascaded Fresnel zone plate lenses are combined with a phased array to increase the gain at wide steering angles of ±52°. The side lenses are tilted to align with the maximum steering angle, and cascaded to increase the focusing gain. The inner lenses increase the gain by 2.45 dB at boresight, and by 3.19 dB at the maximum steering angle. When the side lenses are repositioned, the simulated focusing gain increases to 4.69 dB. Asymmetric amplitude distributions are proposed to prevent the main lobe from splitting. An 8-dement 7-lens prototype operating at 28 GHz achieved a gain from 12.96 dBi to 15.35 dBi with a bandwidth of at least 1.3 GHz for all measured beam directions. The maximum measured azimuthal beamwidth was 27°. A design procedure and a theoretical analysis of diffraction through the lenses are provided. By increasing the SNR, this beamfonning antenna could improve the coverage of 3-sector 5G microcell base stations, and support gigabit wireless links for vehicular, rail, and satellite communications

Conformal Transmitarray for Scan Loss Mitigation with Thinned Reconfiguration

A conformal transmitarray with thinned control is presented, operating at 28 GHz. Its side panels are rotated to align with the maximum steering angle, increasing the gain and reducing the scan loss. The transmitarray is fed by an 8-element linear phased array antenna. Beam focusing to +/- 53 degrees is demonstrated for two different directions, using combinations of crossed-slot unit cells. A unit cell placement rule is proposed to significantly reduce (i.e. thin) the required number of reconfigurable unit cells. A filling factor of 43% was achieved compared to a fully populated design. This reduces the cost and biasing complexity. By minimising scan loss, this antenna could improve the performance of 5G small-cell access points

Duration of untreated eating disorder and relationship to outcomes: A systematic review of the literature

Objective: This systematic review assesses the average duration of untreated eating disorder (DUED) in help‐seeking populations at the time of first eating disorder (ED) treatment and investigates the relationship between DUED and symptom severity/clinical outcomes. / Method: PRISMA guidelines were followed throughout. Selected studies provided information on either: (i) length of DUED, (ii) components of DUED, (iii) cross‐sectional associations between DUED and symptom severity, (iv) associations between DUED and clinical outcomes, or (v) experimental manipulation of DUED. Study quality was assessed. / Results: Fourteen studies from seven countries were included. Across studies, average DUED weighted by sample size was 29.9 months for anorexia nervosa, 53.0 months for bulimia nervosa and 67.4 months for binge eating disorder. A younger age at time of first treatment was indicative of shorter DUED. Retrospective studies suggest that a shorter DUED may be related to a greater likelihood of remission. Manipulation of DUED by shortening service‐related delays may improve clinical outcomes. / Conclusions: Data on length of DUED provide a benchmark for early intervention in EDs. Preliminary evidence suggests DUED may be a modifiable factor influencing outcomes in EDs. To accurately determine the role of DUED, definition and measurement must be uniformly operationalised

Developing an international concept-based curriculum for pharmacology education: The promise of core concepts and concept inventories

\ua9 2023 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.Over recent years, studies have shown that science and health profession graduates demonstrate gaps in their fundamental pharmacology knowledge and ability to apply pharmacology concepts in practice. This article reviews the current challenges faced by pharmacology educators, including the exponential growth in discipline knowledge and competition for curricular time. We then argue that pharmacology education should focus on essential concepts that enable students to develop beyond ‘know’ towards ‘know how to’. A concept-based approach will help educators prioritize and benchmark their pharmacology curriculum, facilitate integration of pharmacology with other disciplines in the curriculum, create alignment between universities and improve application of pharmacology knowledge to professional contexts such as safe prescribing practices. To achieve this, core concepts first need to be identified and unpacked, and methods for teaching and assessment using concept inventories developed. The International Society for Basic and Clinical Pharmacology Education Section (IUPHAR-Ed) Core Concepts of Pharmacology (CCP) initiative involves over 300 educators from the global pharmacology community. CCP has identified and defined the core concepts of pharmacology, together with key underpinning sub-concepts. To realize these benefits, pharmacology educators must develop methods to teach and assess core concepts. Work to develop concept inventories is ongoing, including identifying student misconceptions of the core concepts and creating a bank of multiple-choice questions to assess student understanding. Future work aims to develop and validate materials and methods to help educators embed core concepts within curricula. Potential strategies that educators can use to overcome factors that inhibit adoption of core concepts are presented

A rare presentation of atypical demyelination: tumefactive multiple sclerosis causing Gerstmann's syndrome

r. KS has been supported by a Higher Education Funding Council for England (HEFCE) Clinical Senior Lectureshi

Geographic Coincidence of Increased Malaria Transmission Hazard and Vulnerability Occurring at the Periphery of two Tanzanian Villages.

The goal of malaria elimination necessitates an improved understanding of any fine-scale geographic variations in transmission risk so that complementary vector control tools can be integrated into current vector control programmes as supplementary measures that are spatially targeted to maximize impact upon residual transmission. This study examines the distribution of host-seeking malaria vectors at households within two villages in rural Tanzania. Host-seeking mosquitoes were sampled from 72 randomly selected households in two villages on a monthly basis throughout 2008 using CDC light-traps placed beside occupied nets. Spatial autocorrelation in the dataset was examined using the Moran's I statistic and the location of any clusters was identified using the Getis-Ord Gi* statistic. Statistical associations between the household characteristics and clusters of mosquitoes were assessed using a generalized linear model for each species. For both Anopheles gambiae sensu lato and Anopheles funestus, the density of host-seeking females was spatially autocorrelated, or clustered. For both species, houses with low densities were clustered in the semi-urban village centre while houses with high densities were clustered in the periphery of the villages. Clusters of houses with low or high densities of An. gambiae s.l. were influenced by the number of residents in nearby houses. The occurrence of high-density clusters of An. gambiae s.l. was associated with lower elevations while An. funestus was also associated with higher elevations. Distance from the village centre was also positively correlated with the number of household occupants and having houses constructed with open eaves. The results of the current study highlight that complementary vector control tools could be most effectively targeted to the periphery of villages where the households potentially have a higher hazard (mosquito densities) and vulnerability (open eaves and larger households) to malaria infection