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The extraction of raw materials for infrastructure and construction projects is one of the major contributions made by the stone crushing sector to the economic growth of places like Pakur and Birbhum. Despite the fact that both men and women can find employment in the stone crusher industries, this abstract focuses on the significance of the physical workplace for female stone crusher industry workers in the Pakur and Birbhum areas. The physical workplace environment has a significant impact on how women who work in the stone crushing sector in the Pakur and Birbhum regions perceive their experiences. Stakeholders may empower female employees, improve their well-being, and boost their overall productivity and job satisfaction by offering a welcoming and encouraging environment that includes layout design, ergonomics, safety precautions, and general atmosphere. Such actions will not only help the workforce as a whole but will also advance the stone crushing sector's sustainable growth. Key Words: Physical Environment, Women Workers, Stone Crusher Industry, Liket Scale

To address the possible role of pyrene dimers in soot, chemical dynamics simulations are reported to provide atomistic details for the process of collisional association of pyrene dimers and ensuing decomposition of pyrene dimers. The simulations are performed at 600, 900, 1200, 1600, and 2000 K temperatures (T) with different collisional impact parameters (b; 0-18 A) using the all-atom optimized potentials for liquid simulations intermolecular force field. Corresponding to each b, ensembles of 1000 trajectories are computed up to a maximum time of 110 ps at each T. Microcanonical association rate constants for the pyrene-dimerization processes decrease with an increase in T. The ensuing dissociation of the pyrene dimers is statistical and could be well represented by the Rice-Ramsperger-Kassel-Marcus theory of unimolecular dissociation. Fits of the dissociation rate constants versus the harmonic Rice-Ramsperger-Kassel equation revealed that partial energy randomization occurs among the inter- and intramolecular vibrational modes during the dissociation of pyrene dimers, whereas rotational and translational modes play a significant role. Based on the low probability of association and short lifetime at 1600 (∼13.3 ps) and 2000 (∼12.8 ps) K, it is concluded that pyrene dimers are unlikely to play any major role in soot nucleation processes.

The impact of geometrical confinement on the thermodynamic as well as kinetic aspects of a model cycloaddition reaction in between 1, 3 butadiene and ethylene have been investigated by carrying out density functional theory based calculations. To this end, two organic hosts, ExBox+4 and Cucurbit[7]uril (CB[7]) have been utilized to impose the effect of confinement on the reactants, transition state (TS) and product involved in the reaction. Results suggest that the shape of the host and thereby the nature of confining regime dictates the thermodynamic outcome of the studied reaction. The reaction becomes thermodynamically more spontaneous inside CB[7] as compared to ExBox+4 and that in the 'unconfined' gaseous state. Also the rate constant associated with the reaction increases manifold inside CB[7]. Atoms-in a-Molecule, non-covalent interaction, natural bond orbital as well as energy decomposition analyses suggest that the close geometrical proximity of the reactants inside CB[7] as well as extra stabilization of the TS in the encapsulated state may dictate the outcome.

Confined systems often exhibit unusual behavior regarding their structure, stability, reactivity, bonding, interactions, and dynamics. Quantization is a direct consequence of confinement. Confinement modifies the electronic energy levels, orbitals, electronic shell filling, etc. of a system, thereby affecting its reactivity as well as various response properties as compared to the cases of corresponding unconfined systems. Confinement may force two rare gas atoms to form a partly covalent bond. Gas storage is facilitated through confinement and unprecedented optoelectronic properties are observed in certain cases. Some slow reactions get highly accelerated in an appropriate confined environment. In the current Feature Article we analyze these aspects with a special emphasis on the work done by our research group.

The impact of functionalization as well as guest encapsulation on the optoelectronic properties of the ExBox+4 moiety has been investigated with the aid of density functional theory (DFT) based calculations. To this end, three functionalized variants of the ExBox+4 moiety have been modelled in silico, viz. NH2-ExBox+4-F, CN-ExBox+4-NH2 and NO2-ExBox+4-NH2, whereas coronene (Cor), B-doped coronene (BCor), N-doped coronene (NCor), tetrathiafulvalene (TTF), biphenyl (BiPh), tetracyanoethylene (TCNE) and tetracyanoquinodimethane (TCNQ) molecules have been employed as guests. The results indicate that as a result of functionalization, the ExBox+4 moiety can exhibit tangible non-linear optical (NLO) response properties as vindicated by the first static hyperpolarizability (β). As a result of guest encapsulation, significant variation in the optoelectronic properties of the chosen hosts takes place. BCor/TCNQ/NCor molecules enhance the NLO activity of the hosts while TTF/TCNE suppresses the same. In particular, NCor@host moieties demonstrate very high β values at the static field limit. Time dependent DFT results suggest that in general, the ability of the guest in tuning the transition energy associated with the pivotal electronic transitions of the host plays the dominant role in the observed variation in β. In addition, BCor/NCor@host moieties demonstrate broadband optical absorption capability thereby elucidating the possibility of deriving multi-purpose optoelectronic features such as NLO activity as well as utility in photovoltaic systems. Thermochemical results suggest that all the guest@host systems are stable at 298.15 K. Non-covalent and electrostatic binding forces stabilize the studied systems.

The possibility of sequestrating gas molecules (H2, CO, NO, O3, H2O, and O2) through pristine as well as metal oxide molecule (MO, M = Cu, Ag, Au) supported boron nitride flakes (BNF) has been investigated through density functional theory (DFT) based computations. Thermodynamic (at 298 K) as well as energetic criteria reveal reasonable stability of the MO@BNF moieties. Orbital and electrostatic interactions play crucial roles in stabilizing these systems. MO@BNF moieties, in general, can sequestrate some representative gas molecules, viz., H2, CO, NO, O3, H2O, and O2 in a thermodynamically as well as energetically more facile way as compared to that on pristine BNF. In particular, reversible H2 storage might be feasible at ambient temperature and pressure through MO@BNF. NBO as well as AIM results indicate that the chosen gas molecules, in general, attain an “active” state upon getting adsorbed on MO@BNF moieties as compared to their respective free counterparts.

The impact of the size of the confining regime on the thermodynamic and kinetic outcome of a representative Diels-Alder reaction between ethylene and 1,3 butadiene has been investigated in silico. To this end, two organic hosts namely cucurbit[6]uril (CB[6]) and cucurbit[8]uril (CB[8]) have been considered in order to impose confinement on the reactants/transition state/product of the concerned reaction. The obtained results have been compared with the recently reported (Chakraborty et al. ChemPhysChem 18:2162-2170, 2017) corresponding case of the same reaction happening inside cucurbit[7]uril (CB[7]). Results indicate that as compared to the reaction of ethylene and 1,3 butadiene inside CB[7], both CB[6] and CB[8] cavitands slow down the same reaction at 298.15 K and 1 atm. It appears that the size of the cavitand plays a crucial role in affecting the kinetic outcome of the considered reaction. While CB[7] can enforce productive alignment of the reactants inside its cavity thereby facilitating the reaction, neither CB[6] nor CB[8] can perform the same task as effectively. This situation bears qualitative resemblance with the cases of enzyme catalyzed reactions.

The interaction of BN- and BP-doped graphene nanoflakes with some representative neutral molecules and anions (H2O, HF, SH−, CH3O−, BO2−, F−) has been studied through density functional theory (DFT) calculations. The neutral molecules remain physisorbed whereas all the anions but one remains chemisorbed. Thermodynamically, most of the studied systems are found to be stable. Conceptual DFT-based reactivity descriptors were employed in order to provide rationale behind such observation. The nature of interactions in cases of the anions is predominantly of covalent type whereas the same for neutral molecules is of non-covalent type. The electrostatic and orbital interactions play important roles in stabilising the absorbed moieties. The kinetic stability of the absorbed moieties is confirmed through an atom-centred density matrix propagation simulation at 298 K temperature up to 500 fs. All the studied systems show excellent kinetic stability and remain absorbed up to 500 fs exhibiting rich vibrational and r...

Confinement induced binding interaction patterns for noble gas atoms (Hen/m, Arn, Krn; n = 2, m = 3) atoms inside pristine and -BN doped (3, 3) single walled carbon nanotube (SWCNT) have been studied through density functional theory calculations. The kinetic stability for He dimer and trimer has been investigated at 100 K and 300 K through an ab initio molecular dynamics simulation. The positive role of doping in SWCNT in enhancing the nature of interaction as well as the kinetic stability of the said systems has been found.

The effect of geometrical confinement on the Diels-Alder reactions between some model dienes viz. furan, thiophene, cyclopentadiene, benzene, and a classic dienophile, ethylene has been explored by performing density functional theory-based calculations. The effect of confinement has been imposed by a rigid macrocyclic molecule cucurbit[7]uril (CB[7]). Results indicate that all the reactions become thermodynamically more favorable at 298.15 K temperature and one atmospheric pressure inside CB[7] as compared to the corresponding free gaseous state reactions. Moreover, the rate constants associated with the reactions experience manifold enhancement inside CB[7] as compared to the "unconfined" reactions. Suitable contribution from the entropy factor makes the concerned reactions more facile inside CB[7]. The energy gap between the frontier molecular orbitals of the dienes and dienophiles decrease inside CB[7] as compared to that in the free state reactions thereby allowing facile orbital interactions. The nature of interaction as well as bonding has been analyzed with the help of atoms-in-molecules, noncovalent interaction, natural bond orbital as well as energy decomposition analyses. Results suggest that all the guests bind with CB[7] in an attractive fashion. Primarily, noncovalent interactions stabilize the host-guest systems. © 2017 Wiley Periodicals, Inc.

The impact of functionalization as well as guest encapsulation on the optoelectronic properties of the ExBox

The possibility of functionalizing boron nitride flakes (BNFs) with some selected main group metal clusters, viz. OLi4, NLi5, CLi6, BLI7 and Al12Be, has been analyzed with the aid of density functional theory (DFT) based computations. Thermochemical as well as energetic considerations suggest that all the metal clusters interact with the BNF moiety in a favorable fashion. As a result of functionalization, the static (first) hyperpolarizability () values of the metal cluster supported BNF moieties increase quite significantly as compared to that in the case of pristine BNF. Time dependent DFT analysis reveals that the metal clusters can lower the transition energies associated with the dominant electronic transitions quite significantly thereby enabling the metal cluster supported BNF moieties to exhibit significant non-linear optical activity. Moreover, the studied systems demonstrate broad band absorption capability spanning the UV–visible as well as infra-red domains. Energy decomposition analysis reveals that the electrostatic interactions principally stabilize the metal cluster supported BNF moieties.

The nature of host-guest interaction in between octa acid cavitand (OA) and some representative cationic guests (Li+ , Na+ , K+ , Be+2 , Mg+2 , Ca+2 , Li3 O+ , Na3 O+ , K3 O+ ) as well as heterocyclic moieties like [adenine (A), guanine (G), cytosine (C), thymine (T), uracil (U), and tetrathiafulvalene (TTF)] has been examined with the aid of density functional theory (DFT)-based computations. Thermochemical results indicate that all the guests bind with OA in a thermodynamically favorable fashion at 298.15 K temperature and one atmospheric pressure. OA exhibits high selectivity in binding the lighter cations/metal cluster cations as compared to the heavier congeners along each given series. Moreover, OA exhibits enhanced affinity as well as selectivity in binding A/G/TTF molecules as compared to C/T/U. Noncovalent interaction and energy decomposition analyses reveal that in addition to the van der Waals interaction, significant contribution from electrostatic as well as orbital interactions dictate the outcome in all the host-guest complexes. Time dependent DFT calculations have been carried out to assess the role of the guests in tuning the electronic properties as well as absorption spectrum of OA. © 2017 Wiley Periodicals, Inc.

The viability of sequestering gas molecules (CO, NO, CO

A quantum mechanical analogue of the classically chaotic triple-well oscillator under the influence of an external field and parametric excitation has been studied by using the quantum theory of motion. The on the fly calculations show the correspondence between some dynamical aspects of the classical and quantum oscillators along with a strictly quantum mechanical behaviour in case of diffusion and tunneling. Suitable external conditions have been obtained which can either assist or suppress the movement of quantum particles from one well to another. Quantum interference effects play a critical role in determining the nature of the quantum dynamics and in the presence of strong coupling to the external forces, quantum interference effects reduce drastically leading to decoherence of the quantum wave packet. In such situations, quantum dynamical features qualitatively resemble the corresponding classical dynamical behaviour and a correspondence between classical and quantum dynamics is obtained.

The quantum domain behavior of classical nonintegrable systems is well-understood by the implementation of quantum fluid dynamics and quantum theory of motion. These approaches properly explain the quantum analogs of the classical Kolmogorov–Arnold–Moser type transitions from regular to chaotic domain in different anharmonic oscillators. Field-induced tunneling and chaotic ionization in Rydberg atoms are also analyzed with the help of these theories. Quantum fluid density functional theory may be used to understand different time-dependent processes like ion-atom/molecule collisions, atom-field interactions, and so forth. Regioselectivity as well as confined atomic/molecular systems and their reactivity dynamics have also been explained. © 2013 Wiley Periodicals, Inc.

The feasibility of having MF3 (where M = Rh, Ir, Pd, Pt, Ag, Au) supported AlN nanoflakes (AlNF) was investigated through density functional theory based calculations. The thermodynamic analysis reveals that the superhalogen MF3 molecules can bind with the host AlNF in a thermodynamically favorable way. The nature of interaction in between the metal centers and the host is of partly covalent type whereas the F centers bind with the host in a non-covalent fashion as vindicated by natural bond orbital and atoms-in a-molecule analyses. An ab initio molecular dynamics study carried out at 298 K temperature confirms the stability of the MF3@AlNF moieties in a dynamical context. The MF3 guests can reduce the HOMO-LUMO gaps of the host nanoflakes. In general, the MF3@AlNF complexes can sequestrate polar adsorbates such as CO, NO, and H2O in a thermodynamically favorable way in most of the cases. An ab initio molecular dynamics calculation illustrates that the MF3@AlNF can adsorb the chosen representative polar molecules in a more favorable way as compared to the corresponding adsorption scenario in the case of pristine AlNF.

The possibility of obtaining metal cluster (M3O(+), M = Li, Na, K) supported pristine, B-doped and BN-doped graphene nanoflakes (GR, BGR and BNGR, respectively) has been investigated by carrying out density functional theory (DFT) based calculations. Thermochemical analysis reveals the good stability of M3O(+)@GR/BGR/BNGR moieties. The dynamic stability of M3O(+)@GR/BGR/BNGR moieties is confirmed through an atom-centered density matrix propagation simulation at 298 K up to 500 fs. Orbital and electrostatic interactions play pivotal roles in stabilizing the metal-cluster supported graphene nanoflakes. The metal clusters lower the Fermi levels of the host nanoflakes and enable them to exhibit reasonably good optical response properties such as polarizability and static first hyperpolarizability. In particular, Na3O(+)/K3O(+)@BGR complexes exhibit very large first hyperpolarizability values at the static field limit. All the M3O(+)@BGR/BNGR moieties demonstrate broadband optical absorption encompassing the ultraviolet, visible as well as infrared domains. The metal-cluster supported graphene nanoflakes, in general, can sequestrate polar molecules, viz. CO, NO and CH3OH, in a thermodynamically more favorable way than GR, BGR and BNGR. In the adsorbed state, the CO, NO and CH3OH molecules, in general, attain an 'active' state as compared to their free counterparts.

The potential for gas storage (C2H2, C2H4, C2H6, CO2, CO, H2, N2, NO2, NO) molecules and rare gas (Rg) atoms (He n –Xe n , where n = 1, 2) within the recently synthesized octa acid (OA) moiety is assessed through density functional theory-based computations. It is shown that C2H2, C2H4, C2H6, N2, Kr, and Xe atoms/molecules bind with octa acid in a thermodynamically favorable way. Wiberg bond indices, non-covalent interaction indices, and energy decomposition analyses are used to explore the nature of the interaction between guest atoms and octa acid. The nature of the interaction in between either two guest atoms (in the cases of Rg atoms) or guest and cage atoms is mostly of non-covalent type in nature. An ab initio molecular dynamics simulation carried out at 50 and 298 K temperatures reveal that many of the studied systems particularly concerning polar and π electron cloud containing guest molecules show good dynamical stability at both temperature regimes. Except for the case of Ne-encapsulated octa acid, all other rare gases tend to get liberated from the host at room temperature although they remain inside the host at low temperature, thereby showing good dynamical stability of the Rg-encapsulated octa acid complexes up to 500 fs. In order to reaffirm the dynamical stability, Ne2@OA and CO@OA are studied at 50 and 298 K up to 600 fs as test cases.

The orbital free density functional theory and the single density equation approach are formally equivalent. An orbital free density based quantum dynamical strategy is used to study the quantum-classical correspondence in both weakly and strongly coupled van der Pol and Duffing oscillators in the presence of an external electric field in one dimension. The resulting quantum hydrodynamic equations of motion are solved through an implicit Euler type real space method involving a moving weighted least square technique. The Lagrangian framework used here allows the numerical grid points to follow the wave packet trajectory. The associated classical equations of motion are solved using a sixth order Runge–Kutta method and the Ehrenfest dynamics is followed through the solution of the time dependent Schrodinger equation using a time dependent Fourier Grid Hamiltonian technique. Various diagnostics reveal a close parallelism between classical regular as well as chaotic dynamics and that obtained from the Bohmian mechanics.

The possibility of having neutral Xe-bound compounds mediated by some representative transition metal fluorides of general formula MX3 (where M=Ru, Os, Rh, Ir, Pd, Pt, Ag, Au and X=F) has been investigated through density functional theory based calculations. Nature of interaction between MX3 and Xe moieties has been characterized through detailed electron density, charge density and bond energy decomposition analyses. The feasibility of having compounds of general formula XeMX3 at 298 K has been predicted through thermodynamic considerations. The nature of interaction in between Xe and M atoms is partly covalent in nature and the orbital interaction is the dominant contributor toward these interactions as suggested by energy decomposition analysis.

Background: Mast cells are involved in induction of angiogenesis in the early-stages of tumor development and in modulating blood vessel growth in the later stages of tumor progression. Aims and Objectives: This study was carried out to evaluate the association between mast cell density (MCD) and microvessel density (MVD) in carcinoma in situ (CIS), microinvasive carcinoma (CA) and invasive squamous cell CA of cervix. Materials and Methods: Six cases of CIS, four cases of microinvasive CA and 38 cases of invasive CA were studied over a period of 2 years from August, 2011 to June, 2013. Ten control samples were included in the study. Routine histologic examination was done. Toluidine blue stain was used for MCD determination. Immunohistochemical analysis with CD-34 was done for assessing MVD. Student′s t-test was used to calculate the statistical significance of MCD and MVD. Results: Both MCD and MVD increased from normal samples through CIS to invasive cervical CA. In the four cases of microinvasive CA, the MCD and MVD were more than that of the control samples, but less than that of the six cases of CIS. Conclusion: There is a correlation between mast cell accumulation and angiogenesis in CIS, microinvasive CA and invasive cervical squamous cell CA. MCD and MVD in invasive CA exceed those in CIS and microinvasive CA. It gives us an opportunity to postulate that therapeutic strategies against mast cell mediators and angiogenesis may be of benefit in patients of early-stage cervical CA.

Background and Objective : Many neonates with sepsis die worldwide due to lack of early diagnosis and prompt treatment. This study was carried out to analyze various immunological and hematological parameters singly and in combination to formulate a guideline for the rapid diagnosis of neonatal sepsis. Materials and Methods : In a prospective study, 62 patients having clinical suspicion of neonatal sepsis were evaluated with a battery of investigations. Neonates admitted for other causes and without clinical suspicion of sepsis were selected as controls ( n = 40). The tests included blood culture, hemoglobin (Hb) level, total and differential blood count, absolute neutrophil count (ANC), immature to total neutrophil count (I/T ratio), micro-erythrocyte sedimentation rate (m-ESR), C-reactive protein (CRP), platelet count, serum immunoglobulin M (IgM), and plasma fibrinogen level. Patients were divided into proven cases (positive blood culture) and probable cases (blood culture negative). Results : Positive blood culture was seen in 38 cases (61.3%). Raised m-ESR (>8 mm in 1 st h) was seen in 63.2% of proven and 66.7% of probable cases. An I/T ratio of ≥0.2 was seen in 63.2% and 58.3% of proven and probable cases. Morphological changes were detected in 68.4% of proved and 91.7% of probable cases. Positive CRP test (≥6 mg/L) was found in 84.2% of proven and 100% of probable cases. Raised serum IgM, leukopenia, and neutropenia were seen in minority of patients (11-37%). Raised fibrinogen (>400 mg/L) was seen in the patients as well as in controls. Conclusions : Four useful tests were m-ESR, I/T ratio, morphological changes in neutrophils, and CRP; and were statistically significant ( P < 0.05). Most sensitive test was CRP (84%) and m-ESR was most specific test (94%). Combination of three or more of these four tests were highly specific (95-100%).