Conductance Data Research Articles

Comment on “Interpretation of thermal conductance of the ν=5/2 edge”

We address the interpretation proposed in [S. H. Simon, arXiv:1801.09687] of the thermal conductance data from [M. Banerjee et al., arXiv:1710.00492]. We show that the interpretation is inconsistent with experimental data and the sample structure. In particular, the paper misses the momentum mismatch between contra-propagating modes. Contrary to the claim of the paper, low energy tunneling involves a large momentum change. We consider only the 'small Majorana velocity' mechanism [S. H. Simon, arXiv:1801.09687]. Other mechanisms, interpretations of the experiment, and their difficulties are beyond the scope of this Comment.

Metal-Drug Interactions: Synthesis and Spectroscopic Characteristics, Surface Morphology, and Pharmacological Activity of Ephedrine–HCl Complexes with Mo(V), Nb(V), Ga(III), and Ge(IV)

Four new Mo(V), Nb(V), Ga(III), and Ge(IV) ephedrine complexes, [Mo(Eph)2(Cl)4].Cl, [Nb(Eph)2(Cl)3], [Ga(Eph)2(Cl)3], and [Ge(Eph)2(Cl)2] are synthesized and characterized. Composition and coordination behavior of ephedrine drug towards Mo(V), Nb(V), Ga(III), and Ge(IV) ions are deduced from microanalysis, IR spectra, molar conductance, magnetic and thermal analysis data. These support coordination of the eph ligand in its neutral state. Ephedrine has two powerful chelating sites, OH and NH, that determine its uni- or bidentate mode of action. IR spectra indicate that Mo(V) and Ga(III) coordinate to ephedrine via nitrogen atom of the NH group as a unidentate chelator with six and five coordination geometry, respectively. On the other hand, Eph ligand behaves as a monoanionic bidentate no chelating agent via the NH and deprotonated OH groups in Nb(V) and Ge(IV) complexes. Mo(V) complex demonstrates electrolytic properties, the other complexes are non-electrolytes in DMSO solutions. TG/DTG analysis makes it possible to calculate the number of solvent molecules in and outside the coordination sphere, and estimate stability of the synthesized complexes. The Eph complexes are screened in vitro for antibacterial (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus) and antifungal (Aspergillus flavus and Candida albicans) activities. Anti-cancer action of the Mo(V) and Ga(III) complexes is assessed against the human hepato cellular carcinoma (HepG-2) tumor cell line (IC50 >1000 μg/mL).

On the electrical conductivity of alginate hydrogels.

Hydrogels have been extensively used in the field of biomedical applications, offering customizable natural, synthetic or hybrid materials, particularly relevant in the field of tissue engineering. In the bioelectronics discipline, hydrogels are promising mainly as sensing platforms with or without encapsulated cells, showing great potential in healthcare and medicine. However, to date there is little data in the literature which characterizes the electrical properties of tissue engineering materials which are relevant to bioelectronics. In this work, we present electrical characterization of alginate hydrogels, a natural polysaccharide, using a four-probe method similar to electrical impedance spectroscopy. The acquired conductance data show distinct frequency-dependent features that change as a function of alginate and crosslinker concentration reflecting ion kinetics inside the measured sample. Furthermore, the presence of NIH 3T3 fibroblasts encapsulated in the hydrogels matrix was found to alter the artificial tissue’s electrical properties. The method used provides valuable insight to the frequency-dependent electrical response of the resulting systems. It is hoped that the outcome of this research will be of use in the development of cell/electronic interfaces, possibly toward diagnostic biosensors and therapeutic bioelectronics.

Investigation of molecular interactions of the drug Diclofenac Sodium Salt in water and aqueous sorbitol systems at different temperatures (305.15 K–315.15 K)

The interactions of Diclofenac Sodium Salt (DSS) with water and aqueous sorbitol as a function of temperature have been investigated by volumetric, acoustic and conductance studies. Densities, speed of sound and conductance of DSS in water and aqueous solutions of sorbitol (0.002, 0.004, 0.006) mol·kg−1 have been measured at temperature (T) = (305.15 K, 310.15 K and 315.15 K) and atmospheric pressure. Density data was used to calculate apparent molar volume (Φv), limiting apparent molar volume (Φvo), slope (Sv) and partial molar volumes of transfer (ΔtrΦvo). The ultrasonic speed was used to calculate adiabatic compressibility (β), intermolecular free length (Lf), specific acoustic impedance (Z). The Walden's product was calculated from the conductance and viscosity data. The positive values of (∂2Φv0/∂T2)P and positive values of Λm0η0 with temperature suggest that DSS acts as structure maker in water and aqueous sorbitol systems.

SYNTHESIS, CHARACTERIZATION AND FUNGICIDAL POTENTIALITIES OF SOME TRANSITION METAL COMPLEXES OF BENZIMIDAZOLEDITHIOCARBAMATE BASED LIGAND

New substituted benzimidazole dithiocarbamate ligand (HL) and a set of its transition metal complexes were synthesized and characterized based on the elemental analyses, IR, MS, solid reflectance, magnetic moment, molar conductance and thermal analyses (TGA and DrTG). From the obtained IR data, HL is a neutral tridentate ligand and its complexes were proposed to have the general formulae [MCl(HL)(H2O)2]Cl2.2H2O (M = Cr(III) and Fe(III)] and [MCl(HL)(H2O)2]ClyH2O (for y = 2: M = Mn(II), Co(II) and Cu(II) and for y = 1: M = Ni(II), Zn(II) and Cd(II)). The molar conductance data revealed that all the metal chelates were electrolytes. From the magnetic and solid reflectance spectra, it was found that the geometrical structure of the synthesized complexes is octahedral. The thermal behaviour of these chelates showed that the hydrated complexes loss water molecules of hydration in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. Fungicidal activity of the new ligand and its related complexes was evaluated against three soil-borne fungi that cause many destructive diseases as damping off, root and stem rots of many plants. The tested fungi are Fusarium solani, Rhizoctonia solani and Sclerotium rolfesii. Data obtained showed that introducing an electron-withdrawing nitro group in position (5) of benzimidazole ring enhanced the biological potentialities of the parent ligand and some of its transition metal chelates to show better activity than the standard fungicide Pencycuron.

Synthesis, spectroscopic, thermal, fluorescence properties and molecular modeling of novel Pt(II) complex with schiff base containing NS donor atoms

New transition metal complex of Pt(II) of the Schiff base ligand with (E)-2-((1-(thiophen-2-yl)ethylidene)amino)phenol HL have been synthesized using the ultrasonic irradiation and characterized by physicochemical and spectroscopic methods. The IR spectrum of Pt(II) complex showed that the coordination in metal ions via the imine N and S atoms. Magnetic and UV–Vis spectra showed that the geometrical structure of Pt(II) complex is square planar. The molar conductance data revealed that Pt(II) complex is non-electrolyte. The thermodynamic parameters for thermal decomposition of Pt(II) complex was calculated from analysis of the TG-DTG curves using Hörowitz–Metzger method. The fluorescence of the ligand HL and its Pt(II) complex in different solvents and pH conditions have also been studied in detail. The quenching of the fluorescence intensity of the ligand can be noted obviously, in the presence of Pt(II) ion. Geometry optimization of the compounds was calculated by semiempirical molecular orbital theory PM3 method using Hyperchem 7.52 program.

Synthesis, spectral characterization, quantum chemical calculations, in-vitro antimicrobial and DNA activity studies of 2-(2′-mercaptophenyl) benzothiazole complexes

New ligand (HMPBT) ligand is prepared via condensation of 2-mercaptoaniline and 2-mercaptobenzoic acid in 1:1 ratio. Metal complexes are prepared and characterized by different physical techniques (IR, UV/Vis., 1H NMR, 13CNMR, TGA, DTA, DSC, XRD, magnetic moment and electrical conductance measurements). From the elemental analyses data, the complexes were proposed to have the general formulae [M(MPBT)2] (where M = Co(II), Ni(II), Cu(II) and Zn(II) and MPBT = Ligand. The molar conductance data reveal that all the metal chelates were non-electrolytes. Infrared spectra of the complexes indicate deprotonation and coordination of the thiol SH. It also confirms that nitrogen atom of the benzothiazole group contribute to the complexation. Electronic spectra and magnetic susceptibility measurements as well as quantum chemical calculations reveal square planar geometry for Cu(II) and Ni(II) complexes and tetrahedral geometry for Co(II) and Zn(II) complexes. The activation of thermodynamic parameters are calculated using Coast-Redfern (CR), Horowitz–Metzger (HM), and Piloyan–Novikova (PN). The geometries of the complexes are confirmed using DFT method from DMOL3 calculations and ligand field parameters. The investigated ligand and metal complexes were screened for their in-vitro antimicrobial activities against different types of fungal and bacterial strains. The resulting data assert on the inspected compounds as a highly promising bactericides and fungicides. The binding activities of zinc (II) complex with CT-DNA was investigated using absorption titration, fluorescence spectroscopy and cyclic voltammetry measurements in a Tris-HCl buffer system at pH 7.0. In addition to these methods, gel electrophoresis and viscosity measurements were also carried out to determine DNA-binding activities with zinc (II) complex in a buffer solution. The results indicated that zinc (II) complex interacts strongly with CT-DNA through the intercalative binding mode.

A new macrocyclic ligand salt, 3,5,7,7,10,12,14,14-octamethyl-1,4,8,11-tetraazacyclotetradecane dihydrobromide dehydrate [H 2 L B¢ ]Br 2 ·2H 2 O and some of its metal complexes – Synthesis, characterization and antimicrobial studies

Abstract The reaction of an isomeric ligand LB (a C-chiral isomer of 3,10-C-meso-Me8[14]ane) with dibromoxylene resulted in an unstable N-pendent ligand salt, [(H2LB¢-2H)(-CH2-C6H4-CH2-OH)2] Br2·CH3OH·H2O, which on recrystallization yielded a stable supramolecular ligand salt [H2LB¢]Br2·2H2O.The structure of the new ligand salt was confirmed by X-ray crystallography. The solid state structure of ligand shows that LB¢ is protonated at the N2 and N2A nitrogen atoms and the methyl groups of LB and LB¢ have the same axial and equatorial positions with slight changes in bond angles and bond lengths. The overall charge balance is provided by two bromide anions. In the solid state [H2LB¢]Br2·2H2O shows that the 3, 10 methyl groups are at axial positions and the 5,12 methyl groups at equatorial positions. LB¢ undergoes complexation with different metal salts to form the corresponding metal complexes [M(LB¢)Xm]Yn·xH2O, (M = Cu2+, Ni2+, Co3+, Zn2+, Cd2+ or Pd4+; X & Y = ClO4−, NO3−, Br−, Cl−, SCN−; m, n & x = 0, 1, 2). The metal complexes were characterized on the basis of elemental analyses; IR, UV–Vis and 1H NMR spectroscopy, magnetic and conductance data. These complexes showed different electrolytic behavior in different solvents. The antibacterial and antifungal activities of the ligand LB¢ and its complexes toward different phytopathogenic bacteria were investigated.

New dimeric Schiff base quinoline complexes: Synthesis, spectral characterization, electrochemistry and cytotoxicity

A novel Schiff base ligand (H‐DPPMHQ) derived from 2‐hydrazineylquinoline and 1,3‐diphenyl‐1H‐pyrazole‐5‐carbaldehyde and its dimeric complexes with compositions [Cr(DPPMHQ)Cl]2⋅2Cl and [M(DPPMHQ)Cl]2 (where M = Cu(II), Co(II), Ni(II) and Zn(II)) have been synthesized and characterized using physicochemical methods like elemental analysis, magnetic susceptibility and molar conductivity measurements, multispectral techniques and electrochemical studies. The molar conductance data reveal that all metal chelates are non‐electrolytes, except the Cr(III) complex which shows a ΛM value of 146.82 Ω−1 cm2 mol−1, indicating that it is a 1:2 electrolyte. Infrared spectral results show that the metal is organized through four nitrogen atoms (azomethine and deprotonated imine groups, pyrazole and quinoline rings) besides chlorine atoms. The NH proton is also displaced during complexation, as indicated by 1H NMR spectral data. Based on the electron spin resonance and ligand field parameter data, the bonding parameters of these complexes have been calculated. Using Coats–Redfern and Horowitz–Metzger equations, thermodynamic parameters were determined. The spectral data indicate that the dimeric complexes have octahedral geometry around the central metal ions. The cytotoxic activities of all compounds were evaluated towards human breast cancer (MCF‐7) and lung cancer (A549) cell lines.

Mononuclear oxovanadium(IV) Schiff base complex: Synthesis, spectroscopy, electrochemistry, DFT calculation and catalytic activity

A new complex of oxovanadium, VOL has been synthesized from Schiff base ligand obtained by the condensation of o-phenylenediamine and 5-bromo-salicylaldehyde. All new compounds have been characterized by 1H NMR, IR spectra, UV–Vis spectroscopy, elemental analysis and mass spectrometry. The molar conductance data revealed that the metal complex is a non-electrolyte. Thermal analysis techniques (TGA/DTA) of the ligand and the complex were performed. The proposed structures for the free ligand and the corresponding vanadium complex were corroborated by the use of geometry optimization and conformational analysis. The solid state structure of complex VOL was fully determined by single crystal X-ray diffraction analysis.Similar electrochemical behavior for both the ligand and the corresponding complex have been observed by cyclic voltammetry (CV). The complex gave a metal-based one-electron quasi-reversible redox couple at 606 mV/SCE corresponding to the VOIV/VOV redox process which was consistent with the hydrodynamic voltammograms. Additional peaks in the CVs that were growing with the scan rate have been attributed to consecutive one-electron reduction of the ligand. The catalytic activity of the oxovanadium Schiff base complex VOL was tested in the oxidation reaction of cyclohexene. The efficiency of the catalyst was influenced by the nature of the oxidant. The results showed that the complex was highly active and selective for cyclohexenone in optimized conditions.

Beyond Extinction: Prolonged Conditioning and Repeated Threat Exposure Abolish Contextual Renewal of Fear-Potentiated Startle Discrimination but Leave Expectancy Ratings Intact.

Extinction treatments decrease fear via repeated exposures to the conditioned stimulus (CS) and are associated with a return of fear. Alternatively, fear can be reduced via reductions in the perceived intensity of the unconditioned stimulus (US), e.g., through repeated exposures to the US. Promisingly, the few available studies show that repeated US exposures outperform standard extinction. US exposure treatments can decrease fear via two routes: (1) by weakening the CS–US association (extinction-like mechanism), and/or (2) by weakening the subjective US aversiveness (habituation-like mechanism). The current study further investigated the conditions under which US exposure treatment may reduce renewal, by adding a group in which CS–US pairings continued following fear acquisition. During acquisition, participants learned that one of two visual stimuli (CS+/CS−) predicted the occurrence of an aversive electrocutaneous stimulus (US). Next, the background context changed and participants received one of three interventions: repeated CS exposures, (2) repeated US exposures, or (3) continued CS–US pairings. Following repeated CS exposures, test presentations of the CSs in the original conditioning context revealed intact CS+/CS− differentiation in the fear-potentiated startle reflex, while the differentiation was abolished in the other two groups. Differential US expectancy ratings, on the other hand, were intact in all groups. Skin conductance data were inconclusive because standard context renewal following CS exposures did not occur. Unexpectedly, there was no evidence for a habituation-like process having taken place during US exposures or continued CS–US pairings. The results provide further evidence that US exposures outperform the standard extinction treatment and show that effects are similar when US exposures are part of CS–US pairings.

Synthesis, spectral, DFT modeling, cytotoxicity and microbial studies of novel Zr(IV), Ce(IV) and U(VI) piroxicam complexes

The Zr(IV), Ce(IV) and U(VI) piroxicam anti-inflammatory drug complexes were prepared and characterized using elemental analyses, conductance, IR, UV–Vis, magnetic moment, IHNMR and thermal analysis. The ratio of metal: Pir is found to be 1:2 in all complexes estimated by using molar ratio method. The conductance data reveal that Zr(IV) and U(VI) chelates are non-electrolytes except Ce(IV) complex is electrolyte. Infrared spectroscopic confirm that the Pir behaves as a bidentate ligand co-ordinated to the metal ions via the oxygen and nitrogen atoms of ν(CO)carbonyl and ν(CN)pyridyl, respectively. The kinetic parameters of thermogravimetric and its differential, such as activation energy, entropy of activation, enthalpy of activation, and Gibbs free energy evaluated using Coats-Redfern and Horowitz-Metzger equations for Pir and complexes. The geometry of the piroxicam drug in the Free State differs significantly from that in the metal complex. In the time of metal ion–drug bond formation the drug switches-on from the closed structure (equilibrium geometry) to the open one. The antimicrobial tests were assessed towards some types of bacteria and fungi. The in vitro cell cytotoxicity of the complexes in comparison with Pir against colon carcinoma (HCT-116) cell line was measured.

Study of interaction between cationic surfactant (CTAB) and paracetamol by electrical conductivity, tensiometric and spectroscopic methods

The interaction of a hydrophilic drug, paracetamol with the cationic surfactant cetyltrimethylammonium bromide (CTAB) in an aqueous media has been investigated by using conductometric, tensiometric and spectroscopic methods. The critical micelle concentration (CMC) values have been determined by two different methods and both the methods yielded identical CMC values. The experimental data of conductance and surface tension have been correlated against temperature and concentration using standard relations. The pseudophase separation model has been adopted for calculation of various thermodynamic parameters such as standard free energy ΔGm0, enthalpy, ΔHmic0, and entropy, ΔSmic0, of micelle formation. The increase in the micellization with rising temperature is attributed towards the prevailing hydrophobic-hydrophobic increased interactions between the surfactant-drug aqueous mixtures. From the surface tension data the interfacial parameters such as the maximum surface excess concentration, Γmax, standard Gibbs free energy of adsorption at the air/solvent interface, ΔGad0, and the minimum surface area pre molecule, Amin, were evaluated. Moreover, fourier transform infrared analysis (FTIR) was carried out to estimate the possible interactions prevailing in the miceller systems.

Correlation of electrochemical properties of expanded pyridinium compounds with their single molecule conductance

A series of four expanded pyridinium molecules were used to investigate the correlation between a single molecule conductance (electron transport) and redox (electron transfer) properties at the electrode|electrolyte interface. Quantum chemical calculations of the transmission functions using DFT and non-equilibrium Green's function approach confirmed LUMO‒mediated electron transport in the break junction experiment. Single molecule conductance data can be rationalized within the framework of the non‒resonant tunneling mechanism. More interestingly, a linear correlation was found between the conductance values and the apparent electron transfer rate constants for three molecules of this series.

Fast Data Sorting with Modified Principal Component Analysis to Distinguish Unique Single Molecular Break Junction Trajectories.

A simple and fast analysis method to sort large data sets into groups with shared distinguishing characteristics is described and applied to single molecular break junction conductance versus electrode displacement data. The method, based on principal component analysis, successfully sorts data sets based on the projection of the data onto the first or second principal component of the correlation matrix without the need to assert any specific hypothesis about the expected features within the data. This is an improvement on the current correlation matrix analysis approach because it sorts data automatically, making it more objective and less time consuming, and our method is applicable to a wide range of multivariate data sets. Here the method is demonstrated on two systems. First, it is demonstrated on mixtures of two molecules with identical anchor groups and similar lengths, but either a π (high conductance) or a σ (low conductance) bridge. The mixed data are automatically sorted into two groups containing one molecule or the other. Second, it is demonstrated on break junction data measured with the π bridged molecule alone. Again, the method distinguishes between two groups. These groups are tentatively assigned to different geometries of the molecule in the junction.

Polymer complexes. LXIX. Some divalent metal(II) polymer complexes of potentially bidentate monomer N‐[4‐(5‐methyl‐isoxazol‐3‐ylsulfamoyl)‐phenyl]‐acrylamide: Synthesis, spectroscopic characterization, thermal properties, antimicrobial agents and DNA studies

Monomer of N‐[4‐(5‐methyl‐isoxazol‐3‐ylsulfamoyl)‐phenyl]‐acrylamide (HL) and some transition metal polymeric complexes of the general formula {[M(HL)(OH2)2(OCOCH3)2] xH2O}n (M = Co(II), x = 2; Ni(II), x = 3; Mn(II), x = 2) and [Cd(HL)2(OCOCH3)2] were synthesized and characterized by elemental analysis, IR, UV spectroscopy, conductance measurements, magnetic susceptibility, thermogravimetric analyses and X‐ray diffraction analysis. In all polymer complexes, the spectral data revealed that the ligand act as bidentate neutral molecule and coordinate to metal ion through enolic sulphonamide OH and isoxazol‐N. In all polymer complexes, the spectral data revealed that the ligand act as bidentate neutral molecule and coordinate to metal ion through enolic sulphonamide OH and isoxazol‐N. The molar conductance data revealed that the polymer complexes are non‐electrolytes while UV‐vis and magnetic measurements data have been shown that the polymer complexes have octahedral geometry. All the studies revealed coordination six for the metals in all the polymer complexes and octahedral structures were suggested. The inhibitive effect of HL against C38 steel was investigated in 2 M HCl solution (tafel polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) methods). The type of HL is mixed inhibitor whose adsorption habit onto C38 steel.

Synthesis of Nano-Metric Gold Complexes with New Schiff Bases Derived from 4-Aminoantipyrene, Their Structures and Anticancer Activity

Two new Schiff bases derived from combination of 4-aminoantipyrine with ethylenediamine (L1) or benzaldehyde (L2), gave Au(III) complexes. Their structures were elucidated from microanalytical, magnetic, conductance, and FT-IR, UV-Vis, Mass, and 1H and 13C NMR spectral data. High conductance values indicated electrolytic nature of the complexes. Magnetic moments and electronic spectral data indicated that two synthesized Au(III) Schiff base complexes had a square planar geometry. FT-IR spectroscopic data demonstrated that the Schiff bases were coordinated to Au(III) ions in a tetradentate manner with NNNN donor sites of two 4-amino antipyrine and two azomethine (L1), while L2 Schiff base ligand coordinated to Au(III) ions via its four azomethine nitrogen, which was further supported by the appearance of new bands in IR spectra due to ν(M–N). Activation thermodynamic parameters (E*, ΔH*, ΔS*, and ΔG*) were calculated on the basis of TG curves. Crystalline structures of Schiff bases and their Au(III) complexes were characterized by X-ray diffraction (XRD), their morphology was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Schiff base ligands and their Au(III) chelates were screened for their antimicrobial activity. Cytotoxic activity of those was tested against the human breast cancer (MCF-7) and human hepatocellular carcinoma (HepG-2) tumor cell lines.

Estimating Discharge and Nonpoint Source Nitrate Loading to Streams From Three End‐Member Pathways Using High‐Frequency Water Quality Data

AbstractThe myriad hydrologic and biogeochemical processes taking place in watersheds occurring across space and time are integrated and reflected in the quantity and quality of water in streams and rivers. Collection of high‐frequency water quality data with sensors in surface waters provides new opportunities to disentangle these processes and quantify sources and transport of water and solutes in the coupled groundwater‐surface water system. A new approach for separating the streamflow hydrograph into three components was developed and coupled with high‐frequency nitrate data to estimate time‐variable nitrate loads from chemically dilute quick flow, chemically concentrated quick flow, and slowflow groundwater end‐member pathways for periods of up to 2 years in a groundwater‐dominated and a quick‐flow‐dominated stream in central Wisconsin, using only streamflow and in‐stream water quality data. The dilute and concentrated quick flow end‐members were distinguished using high‐frequency specific conductance data. Results indicate that dilute quick flow contributed less than 5% of the nitrate load at both sites, whereas 89 ± 8% of the nitrate load at the groundwater‐dominated stream was from slowflow groundwater, and 84 ± 25% of the nitrate load at the quick‐flow‐dominated stream was from concentrated quick flow. Concentrated quick flow nitrate concentrations varied seasonally at both sites, with peak concentrations in the winter that were 2–3 times greater than minimum concentrations during the growing season. Application of this approach provides an opportunity to assess stream vulnerability to nonpoint source nitrate loading and expected stream responses to current or changing conditions and practices in watersheds.

Response of Maize Hybrids With and Without Rootworm- and Drought-Tolerance to Rootworm Infestation Under Well-Watered and Drought Conditions.

Anecdotal data in the past have suggested that the effect of the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), on maize yield is greater under drought and the effect of drought is greater under rootworm infestations, but no field experiments have controlled both moisture and rootworm levels. Field studies were conducted in 2012, 2013, and 2014 with treatments in a factorial arrangement of western corn rootworm infestation levels, and maize hybrids (with and without tolerance to drought and rootworm feeding). The experiment was repeated under well-watered and drought conditions in adjacent plots. Leaf water potential and stomatal conductance data suggested significant plant stress was achieved in the drought plots toward the end of the season each year and maize hybrids only played a minor role. In particular, in 2012 and 2013 yield was dramatically lower for the drought experiment than for the well-watered experiment. However, the impacts of rootworm infestation level and maize hybrids on water potential, stomatal conductance, and yield were variable across years and between experiments. In fact, the only year that the main effect of rootworm infestation levels significantly impacted yield was in 2014, when an extremely high infestation level was added and this was only for the well-watered portion of the experiment. Overall, rootworm infestation level played a relatively minor role in maize productivity and it did not appear that soil moisture level influenced that to a large degree.

Synthesis, spectroscopic, thermal and molecular modeling studies of Zn2 +, Cd2 + and UO22 + complexes of Schiff bases containing triazole moiety. Antimicrobial, anticancer, antioxidant and DNA binding studies

A novel series of Zn2+, Cd2+ and UO22+ complexes of ligands namely 1-[(5-mercapto-1H-1,2,4-triazole-3-ylimino) methyl]naphthalene-2-ol (HL1) and [(1H-1,2,4-triazole-3-ylimino) methyl] naphthalene-2-ol (HL2) have been prepared and characterized by different analytical and spectral techniques. The stoichiometry, stereochemistry, conductivity measurements and mode of bonding of the complexes have been elucidated. Accurate comparison of the IR spectra of the ligands with their metal chelates proved the involvement of nitrogen atoms of the azomethine group and/or triazole ring in chelation in addition to the deprotonated hydroxyl oxygen. The UV–Vis and molar conductance data supported the octahedral geometry for the metal complexes. TGA technique has been used to study the thermal decomposition way of the metal complexes and the thermo kinetic parameters were estimated. Valuable information is obtained from calculations of molecular parameters using the molecular modeling techniques. The interaction between the metal complexes and CT-DNA has been studied from which the binding constants (kb) were calculated. The Schiff bases and their metal chelates have shown potent antimicrobial, antioxidant and antitumor activities. The antitumor activities of the compounds have been tested in vitro against HEPG2 cell line and in silico by the molecular docking analysis with the VEGFR-2 receptor responsible for angiogenesis.