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Influenza viruses remain a major public health concern causing contagious respiratory illnesses that result in around 290,000-650,000 global deaths every year. Their ability to constantly evolve through antigenic shifts and drifts leads to the emergence of newer strains and resistance to existing drugs and vaccines. To combat this, there is a critical need for novel antiviral drugs through the introduction of host-targeted therapeutics. Influenza viruses encode only 14 gene products that get extensively modified through phosphorylation by a diverse array of host kinases. Reversible phosphorylation at serine, threonine, or tyrosine residues dynamically regulates the structure, function, and subcellular localization of viral proteins at different stages of their life cycle. In addition, kinases influence a plethora of signaling pathways that also regulate virus propagation by modulating the host cell environment thus establishing a critical virus-host relationship that is indispensable for executing successful infection. This dependence on host kinases opens up exciting possibilities for developing kinase inhibitors as next-generation anti-influenza therapy. To fully capitalize on this potential, extensive mapping of the influenza virus-host kinase interaction network is essential. The key focus of this review is to outline the molecular mechanisms by which host kinases regulate different steps of the influenza A virus life cycle, starting from attachment-entry to assembly-budding. By assessing the contributions of different host kinases and their specific phosphorylation events during the virus life cycle, we aim to develop a holistic overview of the virus-host kinase interaction network that may shed light on potential targets for novel antiviral interventions. [ABSTRACT FROM AUTHOR]

This communication presents the miniaturized low-profile second-order (SO) bandstop frequency selective surfaces (FSSs) for single- and dual-band resonances. The unit cell comprises two identical first-order (FO) elements in a back-to-back configuration with the metal grid in between. Two thin dielectric substrates separate the three metal layers. The proposed FO unit cell consists of intercell-connected spiral resonators (SRs) with capacitively coupled cross loop dipole. The SO filter response of the proposed FSS exhibits a wide stopband ($S_{21} < -10$ dB) bandwidth (BW) of 27.6%. The unit cell has the periodicity of $0.162\lambda _{0}$ , where $\lambda _{0}$ is the free space wavelength at the lower passband. The novelty of the proposed work is a miniaturized simple unit cell geometry, at the millimeter-waveband but not limited to it, with polarization insensitive and high angular stable filter response up to 60° with small variations in the BW. An unconventional four-unit cell element FSS is designed for dual-band SO stopband resonances with the BWs of 8.3% and 13.8%. Prototypes of both FSSs were fabricated and their measured results were found consistent with the simulated filter responses. [ABSTRACT FROM AUTHOR]

This article presents single-layer conformal high angle stable miniaturized triband bandstop frequency selective surface (FSS) for microwave shielding. This new FSS is supported on an ultrathin dielectric substrate and has stable response with change in polarization and incidence angle. Via-less convoluted geometry is adopted in the unit cell design to increase spatial efficiency with a unit cell size of 0.091 λL, where λL is the wavelength at lowest resonance. The proposed FSS exhibits three transmission zeros at 4, 6.95, 11.3 GHz with stopband bandwidth (BW) founds application for shielding the C/X band frequencies for satellite communication. A prototype of the proposed FSS is fabricated. The filter response is measured on normal and on curved surfaces. Simulated and measured transmission coefficients confirm the operating principle of the FSS. Unit cell periodicity of the triband FSS is further reduced by using two layers based 2.5-D geometry. The modified unit cell has a periodicity of 0.038 λL and exhibits stopband BWs center at 0.8, 1.4, and 2.36 GHz. [ABSTRACT FROM AUTHOR]

This article presents a new method of enhancing the capacitance of a single-layer conformal frequency selective surface (FSS) for multifunctional operation. The unit cell of the FSS consists of gridded square loop-loaded modified Jerusalem cross (JC) element. End capacitance of the conventional JC FSS is enhanced by placing parallel diagonal strips, resulting in a pair of reflection zeros near the sidebands. The modified geometry provides high selective stopband filtering that reflects the signal at 20.16 GHz with S21 < −10 dB stopband bandwidth of 20.52%. The FSS shows stable stopband reflection up to a high incidence angle of 85°. The stability in the filter response is also achieved at various conformal angles. The proposed FSS is optimized for dual-band near-perfect absorption. At two resonances 12.76 and 22.54 GHz, the absorption are 99.88% and 99.1%, respectively. Prototypes of the stopband FSS and the dual-band absorber are fabricated to verify the feasibility of the proposed concept. The measured filter and absorber responses are found consistent with the simulated results. As a conformal multifunctional structure, the proposed FSS has the merits of electromagnetic interference shielding and radar cross section reduction in stealth application. [ABSTRACT FROM AUTHOR]

This work presents a miniaturized angularly stable frequency selective surface (FSS) on a single layer substrate. Unit cell comprises of convoluted circular rings connected cross dipole and linear arrow headed dipole printed on both sides of the substrate. A closely spaced dual stop band resonances are obtained at 10 and 14.3 GHz with frequency ratio of 1.43. FSS shows a − 10 dB stopband bandwidth (BW) from 7.32 to 11.05 GHz (40.61%) and 12.68 to 15.97 GHz (22.97%) with >30 dB stop band rejection at center frequencies. FSS poses the features of stable performance under change in polarization and angularly stable response up to 60° incident angle. Later the proposed FSS is printed on grounded thick dielectric substrate and it shows broadband reflection type co to cross polarization conversion from 7.2 to 17.32 GHz (82.54%) with polarization conversion ratio >80% and oblique angle stability up to 35°. To the best of authors' knowledge, this is the first time in literature a single unit cell geometry with two different properties, spatial filtering on transmission and polarization conversion on reflection have been designed and analyzed in details. A finite array with size 25 × 25 of the proposed FSS is fabricated and the measured filter response shows a good agreement with simulated performance at normal and oblique incidences. The proposed FSS is used as a reflector of a dual band monopole antenna and the simulation results shows gain improvement of 5.51 and 3.8 dB at the two stopband frequencies. [ABSTRACT FROM AUTHOR]

In this article, we propose a reconceptualization of the principles and parameters (P&P) framework. We argue that in lieu of discrete parameter values, a parameter value exists on a gradient plane that encodes a learner's confidence that a particular parametric structure licenses the utterances in the learner's linguistic input. Crucially, this gradient parameter hypothesis obviates the need for default parameter values. Default parameter values can be put to use effectively from the perspective of linguistic learnability but are lacking in terms of empirical and theoretical consistency. We present findings from a computational implementation of a gradient P&P learner. The findings suggest that the gradient parameter hypothesis provides the basis for a viable alternative to existing computational models of language acquisition in the classic P&P paradigm. We close with a brief discussion of how a gradient parameter space offers a path to address shortcomings that have been attributed to the P&P framework. [ABSTRACT FROM AUTHOR]

In this paper a compact patch antenna backed with artificial meta-surface known as reactive impedance surface (RIS) is designed for circular polarization in the ISM band. The antenna consists of an asymmetric diagonal slits with pair of complementary split ring resonators (CSRRs) on patch over the RIS structure. Asymmetric slits and pair of CSRRs are inserted on radiating patch to achieve circular polarization. RIS is used for improving the radiation characteristics of the antenna, while RIS-based patch provides good impedance matching over a broad frequency range. Simulated results are in good agreement with the measured results. [ABSTRACT FROM AUTHOR]

Maize, being a nutritious and multipurpose crop requires proper nutrition (N, P, and K) and standardization of sowing time to enhance productivity and profitability under changing climate scenario. Therefore, a field experiment was conducted during monsoon season of 2021 and 2022 at agricultural farm, Lovely Professional University, Punjab, in split plot design with four fertilizer levels (125, 100, 75, and 50% recommended dose of fertilizers; RDF) in main plots and four sowing dates (15 and 30 of June and July) in subplots, replicated thrice. Maize sown on 30 June and fertilized with 125% RDF ensured higher growth attributes throughout crop growth. Besides, comparatively greater yield attributes as well as grain yield (8.22 t ha−1), stover yield (11.86 t ha−1), and harvest index (40.9%) were observed from that treatment combination, and it also recorded higher quality protein and nutrient uptakes but less residual soil fertility. Maize grown on 30 July under application of 50% RDF was the poorest yielder. Further, production economics and energy analysis showed similar trend and indicated that maize grown on 30 June under application of 125% RDF recorded maximum gross return (₹168275 ha−1), net return (₹109565 ha−1), and benefit-cost ratio (2.87) as well as energy output (269084 MJ ha−1) and net energy gain (250750.3 MJ ha−1). [ABSTRACT FROM AUTHOR]

Bioactive compounds are the group of secondary metabolites of plants that have a potent impact on antimicrobial and antibiofilm agents. Although Curcuma longa (turmeric) is well known for its antimicrobial activity, the question arises if curcumin, the primary bioactive compound is only responsible for it or the synergistic and simultaneous contribution of more than one bioactive compound are responsible for this antibiofilm efficacy. The research work aims to determine the efficacy of the extract Curcuma longa has a higher potential of antimicrobial and antibiofilm activity than the purchased curcumin and standard antibiotic. Present work was initiated with GC-MS analysis of the ethanolic extract of Curcuma longa (turmeric) and showed that in addition to curcumin, methyl palmitate de-hydro zingerone had a higher percent of availability within the extract. The in-silico studies also showed that when targeted upon Gram-positive biofilm-forming protein of Staphylococcus aureus (3TIP), curcumin alone had a binding constant value of -6.33 Kcal/mol but showed a value of -17.811 Kcal/mol when acted in association with Dehydrozingerone. Similarly, the binding constant's value changed from -6.07 Kcal/mol to - 23.844 Kcal/mol, when Gram-negative biofilm-forming protein (3ZYB) of Pseudomonas aeruginosa was acted upon by curcumin only and in association with methyl palmitate, respectively. Lower minimum inhibitory concentration (MIC) and higher effectivity in reducing the bacterial quorum sensing (QS) activity of the turmeric extract than pure Curcumin indicated the higher antimicrobial and antibiofilm efficiency of the extract, respectively. This indicated clearly that the synergistic action of all the bioactive compounds imparts the antibiofilm activity of turmeric. The result was further confirmed by the scanning electron microscopic (SEM) studies, fluorescent microscopic studies, and FTIR analysis of EPS as well. [ABSTRACT FROM AUTHOR]

India is the second largest producer of potato in the world. The present study aims at examining the growth, sustainability, market and export situations of Indian potatoes during the period 1966–1967 to 2019–2020 using time series data of area, production, productivity, market prices, export amount and values in major growing states, markets and importing countries, respectively. Descriptive, sustainability, price dependence analysis is taken up to study the internal production and market situation. Box Jenkin’s ARIMA methodology is taken up to forecast the future area, production and productivity of India and the major growing states. To analyse the export behaviour, Markov Chain analysis is taken up. The study reveals that although there have been growths in area, production and productivity, the average productivity is far below the world highest productivity. Sustainability analysis reveals differential sustainability status of major growing states with respect to area, production and productivity. Forecasting of area, production and productivity reveals that India is expected to produce 56 million tonnes of potato from 2.2 million hectares of area with an expected productivity of 25.24 tonnes per hectare, much below the present highest productivity of the world. Study of seasonality of prices and markets cointegration reveals seasonal and lag dependence of prices with only unidirectional market cointegration. The Markov Chain analysis reveals that excepting Saudi Arabia and Oman there will be reduced import of Indian potatoes by other major importing countries. Thus, the findings of the whole study suggest augmentation in the process of production and marketing (both internal and international) for Indian potatoes. [ABSTRACT FROM AUTHOR]