Purpose – In present context of globalization, maintenance of production systems is very important. Many of the organizations are facing a lot of problems in maintenance management. Therefore the purpose of this paper is to identify the main barriers in maintenance management and to rank them for effective maintenance strategies. Design/methodology/approach – To rank the main barriers in maintenance management, technique for order preference by similarity to ideal solution is used. For giving score to different factors a team of three experts was made. All experts were having more than ten years of experience in area of maintenance management. Findings – Lack of top management support, lack of measurement of overall equipment effectiveness (OEE) and lack of strategic planning and implementation have emerged as top three barriers in implementation of maintenance systems in industries. Research limitations/implications – Findings imply that for successful maintenance, top management should be very supportive for taking different initiatives, training programmes, etc. Organizations should try to improve overall performance of machines known as OEE rather than only machines productivity. Originality/value – These findings will be highly useful for professionals from manufacturing sector in implementing effective maintenance management system.

In the present article, a compact triple‐band multistubs loaded resonator printed monopole antenna is proposed. The antenna consists of a quarter wavelength two asymmetrical inverted L‐shaped stubs to excite two resonant modes for 3.5/5.5 GHz bands and one integrated horizontally T‐shaped stub with inverted long L‐shaped stub to excite resonant mode for 2.5 GHz band. By loading these stub resonators along y‐axis with distinct gaps, the antenna resonates at three frequencies 2.57/3.52/5.51 GHz covering the desired bands while keeping compact size of 24 × 30 mm2 (0.2  λ0 × 0.25 λ0). The proposed antenna is fabricated on Rogers RT/duroid 5880 substrate with thickness 0.79 mm and its performance experimentally verified. The measured results reveal that the antenna has the impedance bandwidths of about 210 MHz (2.50‐2.71 GHz), 260 MHz (3.37‐3.63 GHz), and 650 MHz (5.20‐5.85 GHz), for 2.5/3.5/5.5 GHz WiMAX and 5.2/5.8 GHz WLAN band systems. The antenna provides omnidirectional radiation patterns and flat antenna gains over the three operating bands. In addition, the design approach and effects of multistubs resonator lengths on the operating bands are also examined and discussed in detail.

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This article describe the design and measurement of a broadband circularly polarized (CP) monopole antenna for millimeter wave short range 5G Wireless communication applications. This antenna is comprised of a T-shaped monopole antenna with an inverted-L grounded stub and an asymmetric coplanar wave guide feed. To attain the broadband CP, an inverted-L grounded stub is embedded in the coplanar ground and introducing asymmetry in the horizontal T-shaped patch connected feed line monopole antenna. A compact size of 1.877λ L × 1.706λ L × 0.130λ L is accomplished when measured at lower edge frequency (f L,|S11|). For the proposed antenna structure conforming to f L,|S11| , a measured 3-dB axial ratio bandwidth of 13.67% (4 GHz, 27.26-31.26 GHz), impedance bandwidth of 27.9% (8.3 GHz, 25.6-33.9 GHz), peak gain of 7.15dBi, and a bidirectional patterns with a dual sense polarization are attained.

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We have developed a fully automated platform for multiparameter characterization of physiological response of individual and small numbers of interacting cells. The platform allows for minimally invasive monitoring of cell phenotypes while administering a variety of physiological insults and stimuli by means of precisely controlled microfluidic subsystems. It features the capability to integrate a variety of sensitive intra-and extra-cellular fluorescent probes for monitoring minute intra-and extra-cellular physiological changes. The platform allows for performance of other, post-measurement analyses of individual cells such as transcriptomics.Our method is based on the measurement of extracellular metabolite concentrations in hermetically sealed ~200-pL microchambers, each containing a single cell or a small number of cells. The major components of the system are a) a confocal laser scan head to excite and detect with single photon sensitivity the emitted photons from sensors; b) a microfluidic cassette to confine and incubate individual cells, providing for dynamic application of external stimuli, and c) an integration module consisting of software and hardware for automated cassette manipulation, environmental control and data collection. The custom-built confocal scan head allows for fluorescence intensity detection with high sensitivity and spatial confinement of the excitation light to individual pixels of the sensor area, thus minimizing any phototoxic effects. The platform is designed to permit incorporation of multiple optical sensors for simultaneous detection of various metabolites of interest. The modular detector structure allows for several imaging modalities, including high resolution intracellular probe imaging and extracellular sensor readout. The integrated system allows for simulation of physiologically relevant microenvironmental stimuli and simultaneous measurement of the elicited phenotypes. We present details of system design, system characterization and metabolic response analysis of individual eukaryotic cells.

The epidermal cells on the surface of the cotton ovules undergo differentiation to produce fibers, which are single-celled hair-like protrusions resembling the plant trichomes. The initiation of these unicellular fibers from the cotton ovule surface is a complex and tightly regulated process. The initiation step is the cell fate-determining stage, which leads to the commitment of cells that eventually developed into fibers, thus becomes the most crucial phase in fiber development. The in-depth knowledge of molecular regulation is a prerequisite to get a clear view of the fiber initiation process's genetic and epigenetic control. The identification and functional validation of cotton fiber initiation-related genes, few fibreless mutants, transcription factors, microRNAs, epigenetic regulators, as well as the elucidation of the role of phytohormones as signaling molecules, has played a significant role in understanding the cotton fiber initiation process at the molecular level. This review focuses on the comprehensive information regarding the genetic and epigenetic regulation of cotton fiber initiation. Thus, the review will provide readers insight into mechanistic details that operate during cotton fiber initiation.

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