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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.

Oilseeds are one of the most important determinants of India's agricultural economy, next only to cereals and pulses. The selfsufficiently in oilseed obtained during the early 1990s could not be sustained sufficiently. Despite, being the fourth largest oilseed crop-producing nation in the world, India is also one of the largest importers of vegetable oils. This study appraises t he relationship between price and non-price factors to understand the behaviour of major oilseeds (mustard/rapeseed and groundnut) cultivated in India from 1997-98 to 2019-2020. Supply response is the responsiveness of supply, which can be identified using production response to different determining factors. Mustard/rapeseed and groundnut are the oilseeds that are mainly produced in India. This study specifically attempted to quantify the relationship between oilseed production and different factors, such as annual rainfall, annual temperature, yield, and revenue difference for both crops. The findings suggested that yield and revenue difference of mustard with wheat are the most determining factors for mustard production, whereas annual rainfall, the temperature during the growing season, and revenue difference between groundnut with rice and soyabean are the most significant determinants of groundnut's production response. Crop equivalent productivity further validated that groundnut competed and outperformed the two promising crops (soybean and paddy). The trend analysis (1997-98 to 2019-2020) also indicated that wheat was the dominant crop over mustard from 1997-98 to 2013-14. Afterwards, i.e., from 2014-15 to 2019-20, mustard surpassed wheat productivity (on equivalent terms) and outperformed cereal. [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]

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 paper presents a broadband miniaturized Fabry–Perot cavity resonator antenna (CRA) made of novel electromagnetic bandgap (EBG) superstrate as partially reflecting surface (PRS) and reactive impedance surface (RIS) backed rectangular patch antenna. To the best of the authors' knowledge, the proposed EBG exhibits the highest stopband bandwidth (BW) with a bandgap existing between 7.37 and 12.4 GHz (50.9%). Frequency-selective property of the EBG is utilized under plane wave incidence to demonstrate it as PRS superstrate in CRA antenna. The cavity is excited with a rectangular microstrip antenna which is made of two dielectric substrates with an additional RIS layer sandwiched between them. The RIS provides wideband impedance matching of the primary feed antenna. A 7 × 7 array of the EBG superstrate is loaded over the patch antenna having an overall lateral dimension of only 45 × 45 mm2 or 1.62 λ 0 × 1.62 λ 0 where λ 0 is the free space wavelength at the center frequency of 10.8 GHz. The proposed Fabry–Perot CRA (FP-CRA) achieves gain enhancement of 6.59 dB as compared with the reference antenna and has a 10 dB return loss BW of 23.79% from 10.07 to 12.79 GHz. A prototype of the FP-CRA is fabricated and experimentally tested with single and dual layers of EBG superstrate. Measured results show BWs of 21.5 and 24.8% for the two cases with peak realized gain of 12.05 and 14.3 dBi, respectively. Later a four-element antenna array with corporate feeding is designed as the primary feed of the CRA. The simulation result shows a flat gain of >13 dBi with gain variation <1.2 dB over the impedance BW of 13.2%. [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]

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]

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]

This paper presents a compact single feed circularly polarized (CP) antenna along with a frequency selective surface (FSS) that acts as a partially reflective surface over the patch. Patch is loaded with four diagonally asymmetric complementary split ring resonators (CSRRs) in order to achieve circular polarization. In this paper a novel design of reflective type FSS layer is presented at 2.4GHz. The size of FSS unit cell is approximately 0.132λ0 × 0.132λ0, and it is placed at a distance of 0.146λ0 from the patch. Simulated impedance bandwidth of the antenna for S11 < -10 dB is from 2.385 to 2.506 GHz (121 MHz or 4.95%) which covers the entire IEEE 802.11 WLAN band (2.4-2.484 GHz). Position of the four CSRRs on the patch and the height of FSS screen are determined through parametric studies, and the detailed analyses in terms of reflection coefficient, axial ratio, and gain variation are also presented. Gain of the antenna is 3.02 dBic at the operating frequency 2.45GHz. Measured results are in good agreement with the simulated ones. [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]

In this paper, complementary split ring resonator (CSRR) based single feed rectangular microstrip antennas are designed for circular polarization. In the first antenna design, two CSRRs are loaded on ground, and for the second design, two CSRRs are loaded on patch with identical orientation of meta-resonators in both cases. CSRRs are used to diminish the resonance frequency of the antenna, and thus the antenna size miniaturization can be achieved. Overall dimensions of the two antennas are (50×50×1.6)mm3, and the impedance bandwidth for S11 < -10 dB exhibits between 2.3 and 2.4GHz which is useful for wireless communication service. The characteristics of the proposed antennas, i.e., reflection coefficient, axial ratio, gain, and radiation patterns, are observed and compared for the two cases. The proposed two antennas have been designed and simulated using CST Microwave studio 14. The circularly polarized antenna with CSRRs loaded on patch has been fabricated for experimental verification of the simulated results. Measured reflection coefficient, gain, and radiation pattern are in good agreement with the simulated result. [ABSTRACT FROM AUTHOR]

The sweet potato whitefly, Bemisia tabaci (Gennadius), is one of the several species complexes of whitefly that are currently significant agricultural pests. Bemisia tabaci infests more than 600 plant species and thrives under a wide range of temperature conditions. In addition to the direct damage caused by sucking plant sap, it vectors several plant viruses. Heat-shock proteins play a pivotal role in enabling the insect to extend its geographical location, survival, and reproduction under different stress conditions. B. tabaci harbours several endosymbionts under the genera Portiera , Rickettsia , Hamiltonella , Wolbachia , Arsenophonus , Cardinium , and Fritschea that directly or indirectly affect its fitness. By accelerating cuticle biosynthesis and sclerotisation, symbiotic microbes can reduce or enhance tolerance to extreme temperatures and detoxify heavy metals. Thus, symbionts or microbial communities can expand or constrain the abiotic niche space of their host and affect its ability to adapt to changing conditions. The present study delineates the effect of thermal stress on the expression of heat-shock genes and endosymbionts in B. tabaci . Studies of the expression level of heat-shock proteins with the help of quantitative real-time polymerase chain reaction (qRT-PCR) showed that heat- and cold-shock treatment fuels the increased expression of heat-shock proteins (Hsp40 and Hsp70). However, Hsp90 was not induced by a heat- and cold-shock treatment. A significant decrease in the relative titre of secondary endosymbionts, such as Rickettsia , Arsenophonus , and Wolbachia , were recorded in B. tabaci upon heat treatment. However, the titre of the primary symbiont, C . Portiera , was relatively unaffected by both cold and heat treatments. These results are indicative of the fact that Hsp genes and endosymbionts in B. tabaci are modulated in response to thermal stress, and this might be responsible for the adaptation of whitefly under changing climatic scenario., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Barman, Samanta, Ahmed, Dey, Chakraborty, Deeksha, Dutta, Samanta, Tarafdar and Roy.)