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Respiratory infectious diseases (RIDs) are generally spread through person-to-person contact. The human oral cavity, in particular, is a significant source of particles that can cause RIDs. Electric toothbrushes, popular for oral cleaning in recent years, work via high-frequency vibration, which can theoretically spread droplets or small-size aerosols containing viruses. However, the particle emission rates and the potential to spread RIDs using electric toothbrushes are still unclear. In this paper, we investigated the particle emissions from using electric toothbrushes by designing a three-step approach, i.e., a preference survey on toothpaste and toothbrush selections, a behavior test on toothpaste usage, and a standardized particle emission test. The results showed that, first, the toothpaste would be rapidly decomposed into foams, and the emission rates quickly increased to a peak within approximately 10s. Then, the particle emissions decreased slightly and entered a steady phase until the 2-min brushing period stopped. Second, more than half of the detected particles were PM 1, and almost all were PM 5, which can be considered aerosols, and the emissions can reach up to 5433 counts/s. Third, the emissions heavily depended on toothbrush and toothpaste selections, the brushing post, i.e., the teeth. This study suggests that using electric toothbrushes can pose risks of spreading RIDs in enclosed indoor environments such as private homes or, more significantly, public washrooms in school dormitories, airports, train stations, etc. Limited usage of electric toothbrushes and better designs of public washrooms in the context of a global pandemic may be advised. [Display omitted] • Particle emissions were measured during the use of an electric toothbrush. • More than half of the detected particles were PM 1 and almost all were PM 5. • Factors affecting aerosol emissions during electric toothbrushing were analyzed. • The risk of spreading respiratory diseases by electric toothbrushing was estimated. [ABSTRACT FROM AUTHOR]

Operations in the iron and steel industry generate and potentially expose employees to airborne particulates not otherwise classifiable (PNOC) which may contain various forms of silica that have been implicated for respiratory diseases. This study assessed occupational exposure to PNOC fractions (PM5, PM10) and compliance to national occupational exposure limits (OEL) in five workstations at an iron and steel industry. Personal dust samples were collected using standard procedures in three 2hour periods of an 8hour work shift and gravimetrically analysed to estimate time-weighted averages. The highest mean concentrations of PNOC for PM5 (0.65±0.29mg/m3) and PM10 (2.88±0.97mg/m3) recorded for employees at the Box Vibrator in the foundry were significantly lower than the national OELs for PNOC for both PM5 (5mg/m3) and PM10 (10mg/m3) (p<0.05). So were the least concentrations of PNOC for both PM5 (0.004±0.001mg/m3) and PM10 (0.71±0.38mg/m3) recorded at the Administration (p<0.05). Employees across all the five workstations were not exposed to significantly high concentrations of PNOC when compared to national OELs (p<0.05). However, the health risk associated to occupational exposure levels of employees can only be ascertained when specific components of the respirable PNOC are estimated. The concentrations of PNOC fractions to which employees were exposed to were generally a function of distance from the source. [ABSTRACT FROM AUTHOR]

Highlights: [•] Quantum mechanical model for aquatic plant. [•] A microsphere from natural resources. [•] Removal and recovery of Pb(II). [Copyright &y& Elsevier]

Highlights: [•] A new derivative of semduramicin (SemBz) was synthesized. [•] The SemBz and its ability to form complexes was studied by the ESI-MS, DFT, 2D NMR and FT-IR. [•] The fast fluctuations of Li+ and Na+, inside the cavity of the SemBz complexes were described. [Copyright &y& Elsevier]

Highlights: [•] I have synthesized a new derivative of salinomycin. [•] The new isomer was fully characterized by multinuclear 2D NMR, NOESY and MALDI-TOF. [•] The properties of the new compound were additionally study by semiempirical (PM5) and DFT (B3LYP). [•] A potential mechanism of the rearrangement was proposed. [ABSTRACT FROM AUTHOR]

Abstract: The carbon–hydrogen bond dissociation enthalpy (BDE) concept is evaluated as a potential computed indicator of stability of pharmaceutical drug substance candidates – specifically for oxidative stability of these molecules. Computational methods are discussed. Accuracy and validity of the methods are evaluated. BDEs are computed for several well-known molecules, for which stability and degradant identification information is known. Anecdotal correlations are noted between the lowest BDE energies of familiar molecules (sertraline, ezlopitant and related structures, ziprasidone, trovafloxacin, and varenicline), the sites of oxidative lability on these molecules and the identities of oxidative degradants. A low BDE may correlate in general with a reactive site on a molecule, not just an oxidatively susceptible one. [Copyright &y& Elsevier]

Abstract: Cyclic oxaalkyl diamide of o-phthalic acid (CPhDA) has been obtained and its ability to form complexes with calcium cation has been studied by X-ray, ESI MS, 1H and 13C NMR, FT-IR and PM5 semiempirical methods. The ESI MS measurements have proved that in gas phase the 3:1, 2:1 and 1:1 CPhDA–Ca2+ as well as 3:1 and 2:1 CPhDA–Ca(ClO4)+ complexes are formed. In the solid state a 3:1 complex between CPhDA and calcium perchlorate of the CPhDA–Ca(ClO4)2–H2O (3:1:0.5) stoichiometry crystallises as hemihydrate in centrosymmetric space group (R-3) of the rhombohedral system. In crystal, the central Ca2+ cation is coordinated by the three CPhDA ligands via the carbonyl oxygen atoms in a distorted trigonal antiprism. The cationic [Ca(CPhDA)3]2+ complex exhibits a threefold symmetry. Two [Ca(CPhDA)3]2+ cations related by an inversion centre interact with oxygen atom of water molecule that statistically occupies two positions around the inversion centre along the Ca···Ca axis. The FT-IR spectra show the characteristic changes in the frequencies of the amide I and amide II bands upon complexation. The structures of the CPhDA and its complexes with calcium cation are visualised using DFT and PM5 methods and discussed in detail. [Copyright &y& Elsevier]

Abstract: A new hydrazone of 5-nitrosalicylaldehyde with indole-3-acetic hydrazide (NSIAH) has been obtained and its structure has been studied by X-ray, FT-IR and CPMAS in the solid as well as 1H, 13C and 15N NMR in the CH3CN-d 3 and DMSO-d 6 solutions. The hydrazone crystallises in the Pbca space group from the orthorhombic system with a =9.5435(7) Å, b =11.0932(8) Å and c =29.672(2) Å. According to Hirsfeld surface analysis, the whole structure is dominated by H···O interactions (ca. 32.2%) and by H···H interactions (ca. 30%). The other important contributions come from: H···C interactions 19.3%, C···C interactions (π...π electrons; ca. 6.6%) and H···N interactions (also ca. 5.9%). The crystal structure has provided clear evidence that the hydrazone exists in the imine (hydroxy) form in which one intramolecular O–H···N hydrogen bond exists. The existence of this tautomeric form is well reflected by the presence of characteristic bands in the FT-IR spectrum of NSIAH. In CH3CN-d 3 solution the imine (hydroxy) form with the intramolecular O–H···N hydrogen bond is preserved, whereas in DMSO-d 6 this bond is partially broken and stabilized by the intermolecular O–H···O ones with the solvent molecule. As follows from the PM5 calculations of the NSIAH structures solvated by three DMSO-d 6 molecules, structure A including the intramolecular O-H···N hydrogen bond and structure B including only intermolecular hydrogen bonds, are energetically equivalent. [Copyright &y& Elsevier]

Abstract: The photofading characteristics of six monoazo disperse dyes on polyester fabric upon exposure to a carbon arc in air were analyzed in terms of the reactivity (k 0) towards 1O2 and the photosensitivity (f). The photochemical properties of the dyes were estimated by catalytic fading in mixture dyeings of two yellow (pyridone-azo and quinolone-azo) dyes. The k 0 ratios for the componential dyes in the 1:1 mixture dyeings varied with the partner yellow dye, implying that they depend upon the f values and the concentrations of the component dyes as well as the superposition of absorption spectra, and the changes in their concentration, even in the initial stages of fading. The relative k 0 values, as estimated by the sum of the electrophilic frontier densities using the PM5 method were demonstrated experimentally, while taking the influencing factors into consideration. The assumption that the rates of oxidative fading on PET were proportional to the product of two factors of k 0 and f was confirmed as reasonable based on the fading behavior upon exposure to a carbon arc in air of eight disperse azo dyes with a wide range of two factors. [Copyright &y& Elsevier]

The catalytic fading of combination dyeings on polyester fabric of six pyridone-azo and one quinolone-azo yellow disperse dyes imparted by C.I. Disperse Blue 165 as a result of exposure to a carbon arc in air was analyzed in terms of reactivity (k 0) towards singlet oxygen and the photosensitivity (f) of the dyes. Based on the assumption that the rate of photo-fading of single dyeings is proportional to the product of k 0 and f, the fading behavior of both single and mixture dyeings was explained. The k 0 values for the seven azo dyes could be correlated to the sum of electrophilic frontier densities determined using the PM5 method. The nitro groups in the pyridone-azo dyes decreased the reactivity of the electron density in parts of the diazo component. Disperse dyes with excellent light fastness on polyester exhibit low values of both f and k 0. The f values observed for the combination dyeings did not show simple additivity. [Copyright &y& Elsevier]

Abstract: The absorption maxima, , of various organic dyes such as indigo, azobenzene, phenylamine, hydrazone, anthraquinone, naphthoquinone, and malachite green were calculated using the AM1, PM3, and PM5 semiempirical molecular orbital theories with the configuration interaction singles (CIS) and random phase approximation (RPA) approaches. The calculated were then compared with the values obtained by CNDO/S, INDO/S, ab initio CIS, and time-dependent density functional theory (TD-DFT). We found that the values calculated by AM1, PM3, and PM5 were in good correlation with the observed values. When B3LYP/cc-pVDZ optimized geometries were used, the square of the correlation coefficients between the calculated and observed , , at the AM1-RPA, PM3-RPA, and PM5-RPA levels were 0.891, 0.897, and 0.927, respectively. In particular, at PM5-RPA//B3LYP/cc-pVDZ was the largest among those obtained from all the other calculations including TD/B3LYP/cc-pVDZ//B3LYP/cc-pVDZ . Accordingly, the standard deviation of the difference between observed and calculated by the linear regression function at PM5-RPA//B3LYP/cc-pVDZ was the smallest. It was therefore concluded that this method was the most promising for the prediction of of various dyes among the computational methods studied here. When AM1 optimized geometries were used, at the AM1-RPA, PM3-RPA, and PM5-RPA levels were 0.822, 0.841, and 0.901, respectively, and they were also comparable to that at TD/B3LYP/cc-pVDZ//B3LYP/cc-pVDZ. Therefore, although some calibration efforts may be needed for AM1 geometries, PM5-RPA(CIS)//AM1 may be a second candidate available for the prediction of the absorption maxima of dyes, especially in the case of emphasizing computational cost. [Copyright &y& Elsevier]

Abstract: The colchicine complexes with Li+, Na+ and K+ cations have been synthesized and studied by ESI MS, 1H and 13C NMR, FT-IR and PM5 semiempirical methods. It has been shown that colchicine forms stable complexes of 1:1 stoichiometry with monovalent metal cations. For Li+ cations also formation of the 2:1 stoichiometry complexes has been detected. The most stable structures of the complexes are those in which the acetamide groups are involved in the coordination process. The structures of the colchicine complexes with Li+, Na+ and K+ cations are visualized and discussed in details. [Copyright &y& Elsevier]

Abstract: Cyclic diamide of o-phthalic acid with 3,6-dioxa-octyl-1,8-diamine (CPhDA) was synthesised by a new method and its hydrate structure has been studied by X-ray diffraction, FT-IR, NMR and PM5 semiempirical methods. The crystal of this compound is orthorhombic, space group Pbcn, with a =16.7033(11), b =8.8823(5), c =19.6182(12) and Z =8. The IR spectrum of the crystal is consistent with the results obtained by the X-ray study and provides spectroscopic evidence for the formation of the H-bonded complex with water molecules. The calculated structure of the complex and the structural parameters are comparable with those determined by the X-ray method. [Copyright &y& Elsevier]

Abstract: The ability of Oligomycin A (OLA) to form complexes with monovalent cations was studied by the ESI mass spectrometry and PM5 semiempirical method. At low cone voltage values the ESI MS spectra indicate that OLA formes stable 1:1 complexes with Mg2+, Ca2+, Sr2+, Ba2+, Zn2+ divalent cations irrespective of the stoichiometry. With increasing cone voltages the formation of the [OLA+M+(ClO4 or Cl)]+ complexes was preferred. This process occurred simultaneously with the formation of fragmentary metal cation complexes with the exception of Pb2+ ions which does not form complexes with OLA molecule. PM5 semiempirical calculations allowed the visualizations of all structures of (OLA+M)2+ and [OLA+M+(ClO4or Cl)]+ complexes as well as the fragmentary cations. [Copyright &y& Elsevier]

Abstract: The structures and the crystallographic data for monensin and its complexes with Na+, K+ and Ag+ cations have been compared with the parameters calculated by the PM5, PM3 and AM1d semiempirical methods. It is demonstrated that the PM5 calculations are effective for the visualisation of the probable structures of supramolecular species and generate very reliable structural parameters. Only for the complexes of monensin with silver cations the AM1d semiempirical method seems to be more effective than the PM5 and PM3 methods. The most energetically probable structures of monensin hydrates as well as monensin complexes with Na+, K+ and Ag+ cations are visualised. [Copyright &y& Elsevier]

Abstract: The Schiff base of racemic gossypol with 3,6-dioxadecylamine (GSDN) has been synthesised and its structure has been studied by FT-IR, 1H, 13C and 15N NMR spectroscopy as well as by the PM5 semiempirical method. All spectroscopic methods have provided respective evidences that GSDN in solution exists exclusively in the enamine–enamine tautomeric form. The structure of the enamine–enamine tautomer is visualized and the hydrogen bonds stabilising this structure are discussed. [Copyright &y& Elsevier]

Abstract: The Schiff base of racemic gossypol with 4′-aminobenzo-15-crown-5 (GSABC) has been synthesised and studied by FT-IR, 1H and 13C NMR spectroscopy as well as by the PM5 semiempirical method. The spectroscopic methods have provided clear evidence that GSABC exists in solution in the enamine–enamine tautomeric form. The structure of GSABC and the hydrogen bonds within this structure are discussed. Additionally, the aromatic rings from gossypol and benzocrown parts are mutually coplanar, which affects the strength of the hydrogen bonds within the molecular structure and the conjugation between these two parts. [Copyright &y& Elsevier]

Twenty years ago, the landmark AM1 was introduced, and has since had an increasingly wide following among chemists due to its consistently good results and time-tested reliability—being presently available in countless computational quantum chemistry programs. However, semiempirical molecular orbital models still are of limited accuracy and need to be improved if the full potential of new linear scaling techniques, such as MOZYME and LocalSCF, is to be realized. Accordingly, in this article we present RM1 (Recife Model 1): a reparameterization of AM1. As before, the properties used in the parameterization procedure were: heats of formation, dipole moments, ionization potentials and geometric variables (bond lengths and angles). Considering that the vast majority of molecules of importance to life can be assembled by using only six elements: C, H, N, O, P, and S, and that by adding the halogens we can now build most molecules of importance to pharmaceutical research, our training set consisted of 1736 molecules, representative of organic and biochemistry, containing C, H, N, O, P, S, F, Cl, Br, and I atoms. Unlike AM1, and similar to PM3, all RM1 parameters have been optimized. For enthalpies of formation, dipole moments, ionization potentials, and interatomic distances, the average errors in RM1, for the 1736 molecules, are less than those for AM1, PM3, and PM5. Indeed, the average errors in kcal · mol-1 of the enthalpies of formation for AM1, PM3, and PM5 are 11.15, 7.98, and 6.03, whereas for RM1 this value is 5.77. The errors, in Debye, of the dipole moments for AM1, PM3, PM5, and RM1 are, respectively, 0.37, 0.38, 0.50, and 0.34. Likewise, the respective errors for the ionization potentials, in eV, are 0.60, 0.55, 0.48, and 0.45, and the respective errors, in angstroms, for the interatomic distances are 0.036, 0.029, 0.037, and 0.027. The RM1 average error in bond angles of 6.82° is only slightly higher than the AM1 figure of 5.88°, and both are much smaller than the PM3 and PM5 figures of 6.98° and 9.83°, respectively. Moreover, a known error in PM3 nitrogen charges is corrected in RM1. Therefore, RM1 represents an improvement over AM1 and its similar successor PM3, and is probably very competitive with PM5, which is a somewhat different model, and not fully disclosed. RM1 possesses the same analytical construct and the same number of parameters for each atom as AM1, and, therefore, can be easily implemented in any software that already has AM1, not requiring any change in any line of code, with the sole exception of the values of the parameters themselves. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 1101–1111, 2006 [ABSTRACT FROM AUTHOR]

Abstract: The quantum chemical calculations of the non linear optical properties of meso–β doubly linked and meso–meso, β–β, β–β triply linked porphyrin tapes are reported. The π electron movement across the porphyrin tape was enhanced by introducing a donor group and an acceptor group in either side of the tape. Geometries of porphyrin oligomers starting from two units to four units were optimized using the PM5 Hamiltonian employing MOPAC 2002 within the BioMedCAChe 6.1 software package. The calculations of linear and non linear optical properties were performed using the same level of the theory. In addition to the calculation of first static hyperpolarizability, polarizabilities of these molecules are also reported. The frontier orbital energy calculations were done using the same software package. The overall increase of first static hyperpolarizability of porphyrin tapes was observed as the number of porphyrin units increases in the array. The triply linked porphyrin tapes show much better enhancement of NLO properties than the doubly linked tapes. In all cases metallo porphyrin tapes show high hyperpolarizability than the free base porphyrin tapes. The triply linked oligoporphyrins are rigid and not susceptible for twists and turns which makes these compounds promising for a variety of applications. The study suggested that the prophyrin tapes show very large optical non linearities and hence may have potential applications in the development of non linear optical materials. [Copyright &y& Elsevier]

Abstract: Semiempirical MNDO-d molecular orbital calculations have been used for the structural study of chlorophyll b and anhydrous chlorophyll b dimer systems in their respective ground states. A model of chlorophyll b dimer has been considered whereby the magnesium atom is five-coordinate with an oxygen atom in the fifth coordination site. Total energies, net electric charges, and electronic dipole moments have been determined for the ground states of the above-mentioned molecules. The proposed models allow for the examination of distortions within the pyrroles and porphyrin macrocycles of these magnesium complexes. They also permit the estimate of changes in bond lengths, bond angles and dihedrals produced by dimerization via the acetyl oxygen of the carbometoxy group and the central magnesium atom, and changes in the π-electronic system of the chlorin systems. The results obtained are in good agreement with the experimental findings, and they reproduce many of the observed trends. In particular, neutron diffraction crystal structure, NMR and infrared spectra, provide experimental evidence in support of these theoretical predictions. Comparison with other theoretical results, shows that there is a good correlation between the DFT/B3LYP(6-31G*) and the MNDO-d, and also that the MNDO-d performs better than the HF/6-31G* and the PM5 in general. [Copyright &y& Elsevier]

Abstract: The calculation of molecular hyperpolarizability of fluorenyl molecular system was investigated using both ab initio and semi empirical methods. Ab initio optimizations were performed at the Hartree–Fock level using different basis sets, starting with the minimal basis set and then moved to higher basis sets by inserting polarization and diffusion functions. The basis sets incorporated in this study include STO-3G, 3-21G, 6-31G, 6-31+G, 6-31++G, 6-31G(d,p), 6-31+G(d,p), 6-311G, 6-311+G and 6-311++G. The semi empirical investigation was confined to AM1, PM3, MNDO, MNDOd and the newly developed PM5 Hamiltonian. The first static hyperpolarizabilities were calculated at the Hartree–Fock level employing the corresponding basis sets using gaussian 98W. The semi empirical level calculations were performed using MOPAC 2002 within BioMedCAChe 6.1 software package. The first hyperpolarizability is dependent on the method of choice. The first hyperpolarizability, in general, is dependent on the choice of the basis set and clearly influenced after the addition of polarization and diffusion functions. The PM5 method produce results which are comparable with ab initio methodology with a very minimum computational cost. [Copyright &y& Elsevier]

Abstract: The ability to complex formation of oligomycin A (OLA) with monovalent cations was studied by the ESI mass spectrometry, 1H, 13C, 7Li and 23Na NMR spectroscopic and PM5 semiempirical methods. The ESI MS spectra indicated that OLA formed stable 1:1 complexes with all monovalent cations irrespective of the stoichiometry and cone voltage values used. With increasing cone voltages only the degradations of the OLA–Li+ and OLA–Na+ complexes with formation of fragmentary metal cation complexes were found. For OLA complexes with K+, Rb+ and Cs+ cations, with increasing cone voltage the fragmentation of these complexes occurred without the formation of fragmentary metal cation complexes. On the basis of the NMR studies the assignment of the signals of hydroxyl groups in the spectrum of OLA was made and the spectra of its complexes evidenced the involvement of certain oxygen atoms in the complexation process. The PM5 semiempirical calculations allowed visualizations of all structures of the OLA—monovalent cation complexes as well as the fragmentary cations. The most interesting structure was found for OLA–Li+ complex, in which the Li+ cation is fully isolated from the interactions with the environment. [Copyright &y& Elsevier]

Abstract: The Schiff bases of racemic gossypol with l-phenylalanine amino acid methyl ester (GSBA) was studied by FT-IR, 13C and 15N NMR spectroscopy as well as by the PM5 semiempirical method. The spectroscopic methods have provided clear evidence that GSBA exists in the solid state and in solution as enamine–enamine tautomer. The existence of diastereoisomers is very well evidenced in the 13C NMR spectra in the solution by the double character of all carbon atoms'' signals of the naphthalene rings. The structure of GSBA and the hydrogen bonds within this structure are discussed. [Copyright &y& Elsevier]

Abstract: In this work we report a comparative Austin method 1 (AM1), parametric method 3 (PM3), and parametric method 5 (PM5) studies for trans-stilbene in its ground, excited (singlet and triplet), and ionic (positive and negative polarons and bipolarons) states. We evaluated the accuracy of the recently developed PM5 method. PM5 and AM1 predict a non-planar ground and singlet states for trans-stilbene, while PM3 predicts planar ones, which is in agreement with the available experimental data. In general the PM3 and PM5 bond lengths are superior to AM1 while AM1 bond angles are superior to PM3 and PM5 when compared with available experimental data. The PM5 underestimates the cis–trans isomerization energy and and it is not a quite reliable method for the calculation of relative IP values. The presumed PM5 superior performance against AM1 and PM3 was not observed for the stilbene structures. [Copyright &y& Elsevier]

Nodals are signaling factors of the transforming growth factor-ß (TGFß) superfamily with a key role in vertebrate development. They control a variety of cell fate decisions required for the establishment of the embryonic body plan. We have identified two highly conserved transmembrane proteins, Nicalin and Nomo (Nodal modulator, previously known as pM5), as novel antagonists of Nodal signaling. Nicalin is distantly related to Nicastrin, a component of the Alzheimer's disease-associated ?-secretase, and forms a complex with Nomo. Ectopic expression of both proteins in zebrafish embryos causes cyclopia, a phenotype that can arise from a defect in mesendoderm patterning mediated by the Nodal signaling pathway. Accordingly, downregulation of Nomo resulted in an increase in anterior axial mesendoderm and the development of an enlarged hatching gland. Inhibition of Nodal signaling by ectopic expression of Lefty was rescued by reducing Nomo levels. Furthermore, Nodal- as well as Activin-induced signaling was inhibited by Nicalin and Nomo in a cell-based reporter assay. Our data demonstrate that the Nicalin/Nomo complex antagonizes Nodal signaling during mesendodermal patterning in zebrafish. [ABSTRACT FROM AUTHOR]

Quantum chemical calculations at the semiempirical PM3, PM5 and the molecular density functional, B88-PW91 and B88-LYP levels were performed on possibilities of intramolecular trapping and fragmentation products of endo-bicyclo[3.2.1]octa-2,3-dien-6-ol 1 by concerted reaction mechanism. The results have indicated that cyclohexa-2,4-dien-1-ylacetaldehyde 3 and (5Z)-octa-1,5-dien-7-yn-3-ol 4 are competitive reactions and appear more favour than the intramolecular trapping product 2-oxatricyclo[4.2.1.03,8]non-4-ene 2 according to PM3 and B88-LYP levels. [Copyright &y& Elsevier]

The experimental results of the triplet [2+2] photocycloaddition reactions of substituted 2-cyclohexenone 1 with cycloalkenylesters 2, 3, 4 have showed remarkable change in the regioselectivity of the products. The ht/hh product ratio increases with increment of the cycle-size. The FMO investigations in addition to the transition state analysis were used to rationalize such regioselectivity. The FMO method with their orbital coefficients and energies could not explain the reaction selectivity since these values of 2–4 showed tendency to form the hh adduct mainly. PM3, PM5, CIS/6-31G, and B3LYP/6-31G methods were used to locate the hh and ht transition states of the three reactions. As the potential energy barriers (TS1) on the first TS surface for the major products were lower than that for the minor products in most of the cases, the real ratio can be explained in terms of TS analysis. The recently improved PM5 and the B3LYP methods were more successful in this debate as partitioning the activation energy at the potential energy barriers into reactant deformation and the interaction (or repulsion) energies is easy and effective. The changes in the ht/hh ratio with the enlargement of the alkene ring size may be due to the increment of the repulsion energy and large changes in the deformation energy of the reactants. In the transition state structures the stabilities of the major products are thought to be due to the existence of some repulsion between the enone carbonyl and esters in the alkenylesters, and some hydrogen bonding between the reactants. The FMO and second transition state (TS2) energy on the biradical intermediates are also thought to play some role in controlling the product selectivity by lowering the closure energy of the biradicals according to the possibility of their overlapping. [Copyright &y& Elsevier]

Particulate matter (PM) deposition on leaves adversely affects physical, chemical and biological nature of agricultural crops resulting in their loss of productivity and yield. Wheat being a staple food in major parts of Northern India and around the World, has been selected for research purpose by designing a study to explore the probable effects of PM deposition on wheat leaves and wheat crops to ensure the food security. PM 5 (Particulate matter with aerodynamic diameter <5 μm) and Dry Deposited Particulate Matter (DDPM) on wheat leaves (Leaf_DDPM) were collected from the wheat crop field in Indian Agriculture Research Institute (IARI), New Delhi for growing and harvesting season of wheat crops (i.e. December 2014 to April 2015). The EDS (Energy Dispersive Spectroscopy) analysis was used for this study and the individual particle analysis revealed the presence of both acidic and alkaline components like C, Al, Si, Fe, Ca, K, S and Mg. The offline characterization tool i.e. SEM (Scanning Electron Microscope) was utilized for obtaining the micrographs which clearly showed the presence of some angular, sharp-edged and spherical particles consisting of both smooth and rough texture. Apart from that, prevalence of slightly non-spherical particles with aspect ratio of range (>1.20–1.40) and CIR (>0.70–0.80) for both PM 5 and leaf_DDPM were observed. The size distribution of individual particles for both PM 5 (#194 particles) and Leaf_DDPM(#657 particles) revealed that Surface Equivalent Radius (SER) and Volume Equivalent Radius (VER) of particles observed to be 0.40–0.80 μm while surface area to be 0–1 μm2. These particles may easily block stomatal openings (with typical diameter range: 42–51 μm) of wheat leaves and damage internal leaf tissues while particle VER determines the interaction of incoming solar radiation with leaf surfaces. Average PM 5 concentrations ± Standard deviations (μg/m3) were reported to be 231.05 ± 113.03. The XRF (X-Ray Fluorescence) spectrometer analysis of bulk PM 5 revealed the concentrations of non-carbonaceous elements (μg/m3) as N (67.34 ± 16.09), Si (27.44 ± 11.01), Al (7.79 ± 3.37), S (3.88 ± 2.24), Na (2.29 ± 0.94), Mg (1.65 ± 0.62), K (0.51 ± 0.26), Ca (0.60 ± 0.26), Fe (0.54 ± 0.26), Cr (1.10 ± 0.70), Zn (0.05 ± 0.03), P (0.10 ± 0.03), Cu (0.07 ± 0.06). The dominant elemental oxides were calculated as SiO 2 , Al 2 O 3 , SO 4 2 − , Na 2 O, MgO, K 2 O, CaO, Fe 2 O 3 , Cr 2 O 3 , ZnO, P 2 O 5 , Cu 2 O with variable concentrations. In high humid conditions, with relative humidity (~85%) during the vegetative and flowering growth stages of wheat crops, presence of C and S rich acidic and hygroscopic particles may cause the corrosion of wheat leaves that ultimately affect the wheat crops. [Display omitted] • Adverse effects of PM load, chemical composition and morphology on wheat leaves. • Individual PM 5 (#194 particles) and deposited PM on wheat leaves (Leaf_DDPM) (#657 particles) analyzed using SEM-EDS. • Bulk PM 5 XRF revealed presence of both acidic and alkaline PM components. • Elemental oxides mass % calculated and adverse effects studied on wheat leaves. • PM chemical composition, morphology and meteorological parameters altogether decide PM's leaf penetration. [ABSTRACT FROM AUTHOR]

Purpose: Conditions and thresholds applied for evidence weighting of within-codon concordance (PM5) for pathogenicity vary widely between laboratories and expert groups. Because of the sparseness of available clinical classifications, there is little evidence for variation in practice., Methods: We used as a truthset 7541 dichotomous functional classifications of BRCA1 and MSH2, spanning 311 codons of BRCA1 and 918 codons of MSH2, generated from large-scale functional assays that have been shown to correlate excellently with clinical classifications. We assessed PM5 at 5 stringencies with incorporation of 8 in silico tools. For each analysis, we quantified a positive likelihood ratio (pLR, true positive rate/false positive rate), the predictive value of PM5-lookup in ClinVar compared with the functional truthset., Results: pLR was 16.3 (10.6-24.9) for variants for which there was exactly 1 additional colocated deleterious variant on ClinVar, and the variant under examination was equally or more damaging when analyzed using BLOSUM62. pLR was 71.5 (37.8-135.3) for variants for which there were 2 or more colocated deleterious ClinVar variants, and the variant under examination was equally or more damaging than at least 1 colocated variant when analyzed using BLOSUM62., Conclusion: These analyses support the graded use of PM5, with potential to use it at higher evidence weighting where more stringent criteria are met., Competing Interests: Conflict of Interest The authors declare no conflicts of interest., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici , is a devastating disease that threatens yield and quality. Host resistance is considered the most effective and preferred means to control this disease. Wheat landrace Duanganmang (DGM) showed high resistance or near immunity to Blumeria graminis f. sp. tritici mixture from Henan Province, China. DGM was crossed with highly susceptible Chinese wheat landrace Huixianhong (HXH) and cultivar 'Shimai 15' (SM15) to produce genetic populations. The resistance of DGM to Blumeria graminis f. sp. tritici isolate E09 was shown to be controlled by a single dominant Mendelian factor, tentatively designated PmDGM . Marker analysis and 55K single nucleotide polymorphism (SNP) array scanning showed that this gene was positioned in the Pm5 interval (2.4 cM or 1.61 Mb) flanked by Xhenu099 and Xmp1158 in the Chinese Spring reference genome. Homology-based cloning and sequence analysis demonstrated that DGM has the identical NLR gene ( Pm5e ) and RXL gene reported in Fuzhuang 30 (FZ30), conferring and modifying powdery mildew resistance, respectively. However, based on the different reaction patterns to the Blumeria graminis f. sp. tritici isolate B15 between DGM and FZ30, the authors speculate that DGM may have two tightly linked genes that could not be separated in the current mapping population, one of which is PmDGM and the other being Pm5e . Hence, this study provides a valuable resistance resource for improvement of powdery mildew resistance.

Background & Aims: TGR5 (Gpbar-1) is a plasma membrane-bound bile acid receptor expressed in several tissues, including liver, intestine and brain. High levels of TGR5 mRNA have been detected in human and rodent placenta, however, localization of the TGR5 protein has not been studied in this tissue. We aimed at characterizing TGR5 expression in placental tissue and investigated the effect of bile acids and progesterone metabolites, which accumulate during intrahepatic cholestasis of pregnancy (ICP), on receptor expression and localization., Methods: TGR5 mRNA levels and cell-specific localization were determined by quantitative PCR and immunofluorescence, respectively., Results: In human term placentas, TGR5 was mainly localized in fetal macrophages and to a lower extent in trophoblasts. In placentas from ICP patients and pregnant rats with obstructive cholestasis a marked down-regulation of TGR5 mRNA expression was observed. However, the cell-specific distribution of the TGR5 protein was unaffected. Besides bile acids, progesterone and its metabolites (5α-pregnan-3α-ol-20-one/5α-pregnan-3β-ol-20-one), which increase in serum during ICP, were able to dose-dependently activate TGR5. In addition, progesterone metabolites but not their sulfated derivatives nor taurolithocholic acid, significantly down-regulated TGR5 mRNA and protein expression in isolated human macrophages and a macrophage-derived cell line., Conclusion: Since fetal macrophages and trophoblast cells are exposed to changes in the flux of compounds across the placental barrier, the expression of TGR5 in these cells together with its sensitivity to bile acids and progesterone metabolites regarding receptor activity and mRNA expression suggest that TGR5 may play a role in the effect of maternal cholestasis on the placenta., (Copyright © 2013 Elsevier Ltd. All rights reserved.)