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Alzheimer's disease (AD) is one of the prominent causes for disability and lowered quality of life worldwide in elderly population. It has fostered immense burden to AD patients, families and society. Burgeoning progress in the field of pathogenesis over last two decades has persuaded the investigation of novel pharmacological therapeutics that focuses towards the pathophysiological events of AD. Miscellaneous clinical trials, development and testing of interventions aimed at various targets, such as anti‐tau and anti‐amyloid interventions, neurotransmitter modification, neuroprotection and anti‐neuroinflammation interventions, cognitive enhancement and interventions to palliate behavioural symptoms have been carried out. Despite massive efforts to find disease‐modifying therapies, there lingers a vital need for continuing the advancement in progress of the AD research. This review features the new developments of small molecule compounds that will be beneficial in evolution of new AD therapies. In particular, this review briefly describes summary of mechanistic causes chiefly associated with AD and focuses on medicinal approach via small molecule inhibitors that can manage cognitive impairment and dysfunction and may combat Alzheimer's development. [ABSTRACT FROM AUTHOR]

This study concerns wide angular sector (higher order) null synthesis in planar irregular sparse antenna arrays when aperture distributed sub-arrays are used to reduce the computational load. A hybrid optimisation tool has been used to find array element excitations to achieve as low as possible sector nulls for the desired sector width. Performance comparisons have been made for three sub-array configurations based on the obtained numerical results. Various interference jamming scenarios have been considered including single and dual sectors for single-dimensional (θ) (1D) and two-dimensional (θ, ϕ) (2D) nulls. The proposed optimisation scheme has shown to be successful for the synthesis of 1D and 2D sector nulls with depths as low as -100 dB for the given configuration with reduced computational time when compared with the full array. The comparison of achieved null depths for different sub-array sizes and convergence time has also been presented and discussed. [ABSTRACT FROM AUTHOR]

Sparse antenna arrays with irregularly spaced elements are increasingly being used in large array applications such as radio astronomy and radar. These antenna arrays may consist of hundreds of elements and therefore optimisation of these arrays becomes computationally expensive. This study proposes a novel solution to the problem of null synthesis in such arrays, where nulls are formed in prescribed locations for two-dimensional irregular sparse antenna arrays. The technique is based on a subarray and hybrid synthesis solution, where each subarray spans the entire antenna aperture. Single and multiple null formations with array gain maximisation are considered. The technique's effectiveness is demonstrated using evolutionary optimisation algorithms; however, the basic technique can be used with other optimisation methods. The simulation results presented compare the null synthesis performance with and without subarraying and it has shown that the use of subarray results in improved convergence compared with a direct full array synthesis. Furthermore the technique is appropriate for ready application to parallel computer architectures. [ABSTRACT FROM AUTHOR]

ABSTRACT Reduced size dual band patch antenna is designed on pulp fibers-based substrate, obtained from a self-growing plant, Typha angustifolia. The proposed design is low cost and has <10 dB return loss at 2.4 and 5.7 GHz, with 6.9 dBi antenna gain and also has potential for conformal designs. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2146-2148, 2016 [ABSTRACT FROM AUTHOR]

Summary: Quadrifilar helix antenna (QHA) has its applications in satellite communications. This paper presents the performance optimisation of input and radiation characteristics of QHA in the presence of infinite and finite metallic ground planes. For the infinite ground plane, it has been observed that input parameters such as impedance and voltage standing wave ratio (VSWR) are stable, and the antenna has broader half power beamwidth (HPBW). Smaller metallic platforms that act as finite ground planes produce better 3‐dB axial ratio beamwidth and boresight axial ratio. Deployment of QHA on smaller metallic platforms such as nanosatellites and CubeSats enhances the circularly polarised beamwidth of the antenna with improved boresight axial ratio. However, on large low earth orbit (LEO) satellites, stable input characteristics and broader HPBW have been achieved at the cost of narrow circularly polarised beamwidth and degraded boresight axial ratio. [ABSTRACT FROM AUTHOR]