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Atomic hardness is an important periodic descriptor which can govern chemical reactivity and stability. A number of theoretical models are available to compute atomic hardness. In this report, we have suggested a new and simple approach to compute atomic hardness. Considering periodic relationship of atomic hardness with nucleophilicity index, effective nuclear charge and atomic radius, this model is derived to compute hardness of 103 elements of the periodic table. Our proposed scale satisfies all sine qua non of the periodic table. Characteristic periodic properties viz. lanthanide contraction, chemical inertness of noble gases, relativistic effect is quite distinct in our computed result. We have also calculated molecular hardness invoking Hardness Equalization Principle. A strong correlation between our computed data and their experimental counterparts justifies our study.

This study investigates students’ perceptions of Generative Artificial Intelligence (GenAI), with a focus on Higher Education institutions in Northern Ireland and India. We collect quantitative Likert ratings and qualitative comments from 1211 students on their awareness and perceptions of AI and investigate variations in attitudes toward AI across institutions and subject areas, as well as interactions between these variables with demographic variables (focusing on gender). We found the following: (a) while perceptions varied across institutions, responses for Computer Sciences students were similar, both in terms of topics and degree of positivity; and (b) after controlling for institution and subject area, we observed no effect of gender. These results are consistent with previous studies, which find that students’ perceptions are predicted by prior experience; crucially, however, the results of this study contribute to the literature by identifying important interactions between key factors that can influence experience, revealing a more nuanced picture of students’ perceptions and the role of experience. We consider the implications of these relations, and further considerations for the role of experience.

The study of bimetallic nanoalloy clusters is of considerable interest due to its interesting electronic, optical, magnetic and catalytic properties. The geometrical structure and electronic properties of AunPt (n = 1–8) nanoalloy clusters are studied by using the density functional theory methodology. The result exhibits that the ground-state configurations of AunPt clusters favour planar confirmation in this molecular range. The most stable cluster is Au3Pt, which is having rhombus structure with symmetry group C2v and can be considered as building blocks for developing large clusters. The computed HOMO-LUMO energy gap of Au3Pt nanoalloy cluster is 1.741 eV. The energy gap in this particular range supports the use of bimetallic clusters as nonlinear optical devices and optoelectronic materials. The DFT-based global descriptors viz. HOMO-LUMO energy gap, electronegativity, hardness, softness and electrophilicity index are also studied. The computed HOMO-LUMO energy gap and chemical hardness exhibit a pronounced odd-even oscillation behaviour as a function of cluster size, n.

A comparative study of geometry, relative stabilities, optoelectronic and thermochemical properties of [Cu X -Ag-Au] λ and [Cu X+2 ] λ (λ = 0, ± 1; X = 1 − 13) nanoalloy clusters is performed by using density functional theory (DFT) technique. The ground state configuration as well as low lying isomers of these clusters are analyzed. Binding energies, fragmentation energies and second-order difference in energies of these clusters show an odd-even alteration behavior with the size of the cluster. Result exhibits that incorporation of Ag and Au atoms in [Cu X+2 ] enhances the energy gap of overall system in most of the cases. Highest Occupied Molecular Orbital (HOMO) - Lowest Unoccupied Molecular Orbital (LUMO) energy gap of [Cu X+2 ] and [Cu X -Ag-Au] are found between 0.870 and 3.490 eV and 1.237–3.196 eV respectively. The result shows that HOMO-LUMO energy gap of [Cu X -Ag-Au] clusters are in the optimum range needed for photovoltaic devices, it signifies that these clusters may be considered as potential candidate for optoelectronic and photovoltaic devices. Data reveals that [Cu X -Ag-Au] at X = 4 show maximum value of HOMO-LUMO gap, Vertical Ionization Energy (VIE), and hardness whereas minimum value of softness. However, at X = 13 it has demonstrated minimum value of HOMO-LUMO gap, and hardness whereas maximum value of softness and electrophilicity index. It is observed that [Cu 14 ] and [Cu 11 -Ag-Au] clusters have significant electron infusion abilities due to large Vertical Electron Affinity (VEA) value. Optical properties – optical electronegativity, refractive index, dielectric constant as well as infrared and Raman spectra of these clusters are analyzed. For [Cu X+2 ], minimum and maximum refractive index is found in case of [Cu 10 ] and [Cu 14 ] respectively, whereas for trimetallic clusters, [Cu 13 -Ag-Au] and [Cu 4 -Ag-Au] show the maximum and minimum refractive index. Thermochemical properties like thermal energy, heat capacity, zero-point correction and entropy of these systems increase with the cluster size, whereas Gibbs free energy follows reverse pattern.

C. parapsilosis is the second or third most common opportunistic human-pathogenic Candida species, being responsible for severe fungal infections among immunocompromised patients, especially low-birth-weight infants (0 to 2 years of age). Among the major virulence factors that pathogenic fungi possess is the ability to compete with the host for essential micronutrients, including iron. Accessible iron is required for the maintenance of several metabolic processes. In order to obtain accessible iron from the host, pathogenic fungi have developed several iron acquisition and metabolic mechanisms. Although C. parapsilosis is a frequent cause of invasive candidiasis, little is known about what iron metabolic processes this fungus possesses that could contribute to the species’ virulent behavior. In this study, we identified the multicopper oxidase FET3 gene that regulates iron homeostasis maintenance and also plays important roles in the morphology of the fungus as well as in biofilm formation, two additional factors in fungal virulence. Among all the essential micronutrients, iron plays an important role in mammalian biology. It is also essential for pathogens infecting mammalian hosts, including bacteria, fungi, and protozoans. As the availability of accessible iron is limited within the mammalian host, several human-pathogenic fungal pathogens, such as Candida albicans , Cryptococcus neoformans , Candida glabrata , and Aspergillus fumigatus , have developed various iron uptake mechanisms. Although Candida parapsilosis is the second or third most common non- albicans Candida species associated with systemic and superficial Candida infections in immunocompromised patients, the mechanisms of iron uptake and homoeostasis remain unknown in this fungus. In the current report, we show that a homologue of the multicopper oxidase gene FET3 is present in the genome of C. parapsilosis ( CPAR2_603600 ) and plays a significant role in iron acquisition. We found that homozygous deletion mutants of CPAR2_603600 showed defects under low-iron conditions and were also sensitive to various stressors. Our results also revealed that the levels of pseudohypha formation and biofilm formation were reduced in the null mutants compared to the wild type. This phenotypic defect could be partially rescued by supplementation with excess iron in the growth medium. The expression levels of the orthologues of various iron metabolism-related genes were also altered in the mutants compared to the parental strain. In conclusion, our report describes the role of CPAR2_603600 in iron homoeostasis maintenance as well as morphology and biofilm formation regulation in this pathogenic fungus. IMPORTANCE C. parapsilosis is the second or third most common opportunistic human-pathogenic Candida species, being responsible for severe fungal infections among immunocompromised patients, especially low-birth-weight infants (0 to 2 years of age). Among the major virulence factors that pathogenic fungi possess is the ability to compete with the host for essential micronutrients, including iron. Accessible iron is required for the maintenance of several metabolic processes. In order to obtain accessible iron from the host, pathogenic fungi have developed several iron acquisition and metabolic mechanisms. Although C. parapsilosis is a frequent cause of invasive candidiasis, little is known about what iron metabolic processes this fungus possesses that could contribute to the species’ virulent behavior. In this study, we identified the multicopper oxidase FET3 gene that regulates iron homeostasis maintenance and also plays important roles in the morphology of the fungus as well as in biofilm formation, two additional factors in fungal virulence.

We have studied the structure and optical properties of bimetallic (CuAg)n (n = 1–6) nanoalloy clusters by using density functional theory (DFT) method. The computed data shows that HOMO-LUMO energy gaps of the clusters are in the range of 1.444–3.066 eV. The most stable cluster (CuAg)3 with symmetry group C1 and singlet spin multiplicity has an energy gap 3.066 eV, whereas the cluster (CuAg)6 with symmetry group C2 and singlet spin multiplicity shows the least energy gap (1.444 eV). Our study reveals an interesting correlation between energy gap, optical electronegativity, and refractive index. Computed data exhibits that clusters, in which Ag atoms are placed on the edge position and have less number of Ag–Ag bonds, display a large frequency range and the maximum intensity of IR and Raman spectra.

Recently, we have defined atomic polarizability, a Conceptual Density Functional Theory (CDFT)-based reactivity descriptor, through an empirical method. Though the method is empirical, it is competent enough to meet the criteria of periodic descriptors and exhibit relativistic effect. Since the atomic data are very accurate, we have applied them to determine molecular polarizability. Molecular polarizability is an electronic parameter and has an impact on chemical–biological interactions. Thus, it plays a pivotal role in explaining such interactions through Structure Activity Relationships (SAR). In the present work, we have explored the application of polarizability in the real field through investigation of chemical–biological interactions in terms of molecular polarizability. A Quantitative Structure–Activity Relationship (QSAR) model is constructed to account for electronic effects owing to polarizability in ligand–substrate interactions. The study involves the prediction of various biological activities in terms of minimum block concentration, relative biological response, inhibitory growth concentration or binding affinity. Superior results are presented for the predicted and observed activities which support the accuracy of the proposed polarizability-QSAR model. Further, the results are considered from a biological viewpoint in order to understand the mechanism of interactions. The study is performed to explore the efficacy of the computational model based on newly proposed polarizability and not to establish the finest QSAR. For future studies, it is suggested that the descriptor polarizability should be contrasted with the use of other drug-like descriptors.

Initializing a set of qubits to a given quantum state is a basic prerequisite for the physical implementation of quantum-information protocols. Here, we discuss the polarization of the electronic and nuclear spin in a single nitrogen vacancy center in diamond. Our initialization scheme uses a sequence of laser, microwave and radio-frequency pulses, and we optimize the pumping parameters of the laser pulse. A rate equation model is formulated that explains the effect of the laser pulse on the spin system. We have experimentally determined the population of the relevant spin states as a function of the duration of the laser pulse by measuring Rabi oscillations and Ramsey-type free-induction decays. The experimental data have been analyzed to determine the pumping rates of the rate equation model.

Abstract Intense droughts in recent years are a global concern. The duration and timing of drought for forests have not been researched as much as crops. This study aims to utilize big earth data to analyse the consequences of drought on forest based on drought and vegetation indices derived from remote sensing. The study area is Sal Forest (Shorea robusta) in Bangladesh. Vegetation indices such as NDVI and EVI are correlated with drought indices for the years 2000–2020. The data is collected via Google Earth Engine and the R statistical software environment is used for data analysis. Seasonal adjustment was conducted to remove the biases due to seasonality. Results showed that the timing for the loss of forest vitality is dependent on drought severity. Lagged correlation was used to identify the lags between drought severity and vitality via drought and vegetation indices. From 2000 to 2020, the intensity of drought was moderate (0.95). There is a lag between drought and a decrease in forest vitality. This lag decreases as the severity and duration of drought increase. Severe droughts in Sal Forest create an almost immediate impact with worsening conditions but show a lag of 3–4 months and 2–3 months for low and moderate drought severity, respectively. The NDVI anomaly shows that drought has adverse effects during growth periods. The methodology of this study can be replicated across various forest types, and further improvements would require in situ data coupled with phenological observations.

Electrophilicity index (ω) is an important theoretical construct of atoms and molecules and is widely used to understand various chemical phenomena and determine physico-chemical properties. Accordingly, it becomes useful to find an accurate expression for it which is free from any inconsistencies. In view of this, a simple yet rigorous expression is proposed to compute Electrophilicity Index. Since our model is based on ionization potential and electron affinity, it provides a more reliable measure for any electronic changes taking place in a species. Our suggested definition is free from any operational and dimensional discrepancies. We have reported atomic electrophilicity indices for 74 elements of the periodic table invoking our proposed ansatz. The proposed model follows all the sine qua non of existing scale of electrophilicity index. Electrophilicity Equalization Principle is also validated through our computed values. In general, the new expression appears to be powerful and suitable for application in diverse realms.