First Measurement of the Nuclear-Recoil Ionization Yield in Silicon at 100 eV.

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

Induction of defence-related proteins by selected plant growth regulators and biocontrol agents against guava root knot nematode, Meloidogyne enterolobii.

Guava is an important edible and economic fruit crop distributed worldwide. It is widely infested with root knot nematode, Meloidogyne enterolobii which plays a vital role in causing economic losses. Several management strategies were performed to enhance the health status of guava and also to reduce root knot nematode infestation. Among the different aspects, application of plant growth regulators on guava plants under nursery conditions against root knot nematode, M. enterolobii was performed. The guava plants were treated with Salicylic acid (100 ppm), Jasmonic acid (100 ppm), and Indole 3-Butyric Acid (1000 ppm) alone and in combination of two and three. The result of this study revealed that IBA at 1,000 ppm alone (T3) and combined application of plant growth regulators viz., (T4) - Salicylic acid (100 ppm) + Jasmonic acid (100 ppm) + Indole 3-Butyric Acid (1,000 ppm) showed reduction in the nematode population and establishment of new roots (compensatory) and tertiary roots. The combined application of PGRs also increased the Plant height, root length, chlorophyll index, photosynthetic rate, transpiration rate, stomatal conductance, and chlorophyll fluorescence. The activity of various enzymes like total phenols, peroxidase, polyphenol oxidase, acid phosphatase, and phenylalanine ammonia lyase were influenced and developed resistance against root knot nematode, M. enterolobii. Under field conditions, application of Pochonia chlamydosporia and Purpureocilium lilacinum reduced the nematode infestation besides increasing the yield attributes of guava plants.

Diosgenin derivatives developed from Pd(II) catalysed dehydrogenative coupling exert an effect on breast cancer cells by abrogating their growth and facilitating apoptosis via regulating the AKT1 pathway.

Palladium metallates containing 4-oxo-4H-chromene-3-carbaldehyde derived ONS donor Schiff bases were synthesized and their efficacy was tested in the direct amination of diosgenin - a phyto steroid. Based on the pharmacological importance of diosgenin, the obtained derivatives were exposed to study their effect on breast cancer cells where they significantly reduced the growth of cancer cells and left non-malignant breast epithelial cells unaffected. Among the derivatives, D3, D4 and D6 showed a better anti-proliferative effect and further analysis revealed that the D3, D4 and D6 derivatives markedly promoted cell cycle arrest and apoptosis by attenuation of the AKT1 signalling pathway.

Assessing the Validity and Reliability of Tooth Widths and Bolton Ratios Obtained from Digital Models and Plaster Models.

Aim: The aim of the study is to compare and evaluate the validity and reliability of tooth widths and Bolton ratios measured from digital models obtained from intraoral scanners and plaster models derived from alginate and polyvinyl siloxane impression materials. Materials and Methods: Alginate and polyvinylsiloxane impression was taken for 40 subjects, orthokal stone was poured and grouped as Group I and Group II, respectively. Intraoral scanning was done using Trios Pod 3shape for the same patients, digital models were obtained and grouped as Group III. OrthoAnalyzer software was used for obtaining measurements in digital models and Aerospace Vernier calipers in plaster models. The validity and reliability of the three groups were quantified and compared. Results: Validity measurements showed significant differences between tooth widths and Bolton ratios obtained from digital models and plaster models indicating higher accuracy for plaster models whereas reliability coefficients were excellent for digital models indicating better reproducibility of values. Conclusion: The study shows significant differences in accuracy on measuring with vernier calipers and Orthoanalyzer software showing plaster models are still better than digital models for measuring tooth widths and bolton ratios.

Binuclear Ni(II) complexes containing ONS donor Schiff base ligands: Preparation, spectral characterization, X-ray crystallography and biological exploration.

Four binuclear Ni(II) complexes [[Ni2(H-DEAsal-tsc)2(µ-dppm)]·2Cl (1), [Ni2(DEAsal-mtsc)2(µ-dppm)] (2), [Ni2(DEAsal-etsc)2(µ-dppm)] (3) and [Ni2(DEAsal-ptsc)2(µ-dppm)] (4)] were synthesized from the ligands namely 4(N,N)-diethylaminosalicylaldehyde-4(N)-thiosemicarbazone [H2-DEAsal-tsc] H2L1/4(N,N)-diethylaminosalicylaldehyde-4(N)-methyl thiosemicarbazone [H2-DEAsal-mtsc] H2L2/4(N,N)-diethylaminosalicylaldehyde-4(N)-ethyl thiosemicarbazone [H2-DEAsal-etsc] H2L3/4(N,N)diethylaminosalicylaldehyde-4(N)-phenyl thiosemicarbazone [H2-DEAsal-ptsc] H2L4 and 1,1'-bis(diphenylphosphino)methane (dppm) and characterized by a number of spectro analytical techniques. The molecular structure of complexes [Ni2(H-DEAsal-tsc)2(µ-dppm)]·2Cl (1) and [Ni2(DEAsal-ptsc)2(µ-dppm)] (4) have been confirmed by single crystal X-ray diffraction studies. The analysis indicated that in complex 1, the ligand [H2-DEAsal-tsc] coordinated as monobasic tridentate donor through phenolic oxygen, azomethine nitrogen and thione sulfur atoms. However, in complex 4, the ligand [H2-DEAsal-ptsc] behaved as dibasic tridentate donor with thiolate sulfur coordination. Their ability to bind with Calf Thymus Deoxyribonucleic acid (CT-DNA) and Bovine Serum Albumin (BSA) were analysed spectrometrically. Intercalative interaction of the complexes with DNA was confirmed by ethidium bromide (EB) displacement studies and DNA viscosity measurements. The interaction mechanism of the complexes with BSA was found as static. In vitro antiproliferative studies of the ligands and complexes in A549 (human lung carcinoma cancer), MCF-7 (human breast cancer) and HeLa (human cervical cancer) cell lines witnessed significant cytotoxic nature of the complexes with low IC50 values (in µM) than the standard metallo-drug cisplatin. Further, the results of Lactate Dehydrogenase (LDH) and Nitric oxide (NO) release assays supported the effectiveness of the complexes on the above said cancer cells.

Perceptions on the adsorption of COPD biomarker vapors on violet phosphorene nanosheet - A first-principles study.

We systematically investigated the adsorption characteristics of chronic obstructive pulmonary disease (COPD) biomarker volatiles on violet phosphorene with density functional theory approach. The formation energy of violet phosphorene indicates its stable structure. The electronic properties of violet phosphorene credit that it is a suitable material for biosensors. We explored the adsorption mechanism of hexanal and nonanal molecules based on electron density variation, the density of states (DOS) spectrum, band structure analysis of violet phosphorene. The results of adsorption energy, charge transfer also strengthen that COPD volatile organic compounds can be adsorbed on violet phosphorene. The proposed report strongly values that violet phosphorene as a prominent candidate to identify the biomarkers in COPD patients from the exhaled breath.

para metallation of 3-acetyl-chromen-2-one Schiff bases in tetranuclear palladacycles: focus on their biomolecular interaction and in vitro cytotoxicity.

Three tetranuclear (1-3) complexes and a mononuclear (4) palladium(ii) complex were synthesized from 3-acetyl-chromen-2-one Schiff base ligands [H2-3MAC-Rtsc] (where R = H [H2-3MAC-tsc]; CH3[H2-3MAC-mtsc]; C2H5[H2-3MAC-etsc] or C6H5[H2-3MAC-ptsc]) and potassium tetrachloropalladate. Their formation was confirmed by spectroscopic techniques and X-ray crystallographic analysis. Their ability to bind with DNA and albumin was analysed by using absorption and emission titrations. The MTT assay was carried out to analyze the anticancer potential of the ligands and synthesized complexes against HepG2 (human liver cancer) and HT-29 (human colon cancer) cells. In addition, the compounds were less toxic when tested against the human normal keratinocyte cells (HaCaT). Ligands and complexes displayed better cytotoxicity with lower IC50 values than the standard drug cisplatin. Further AO-EB and DAPI staining assays were carried out to detect the mode of cell death induced by the complexes i.e. apoptosis or necrosis. The complex 3 showed better cytotoxicity and was further subjected to flow cytometric analysis. The results suggested that the complex 3 induced apoptotic cell death.

Nucleobases adsorption studies on silicane layer: A first-principles investigation.

The geometric stability of silicane layer (H-Si) is explored using the first-principles investigation. The electronic properties of H-Si are ascertained, and tunable electronic properties of H-Si leads to the application in sequencing the deoxyribonucleic acid (DNA)/riboxy nucleic acid (RNA). The adsorption behavior of DNA/RNA nucleobases on H-Si is explored using Bader charge transfer, adsorption energy, and energy gap. Moreover, there is a significant change in the band structure and density of states of H-Si upon adsorption of nucleobases. We observed that all the nucleobases are physisorbed on H-Si via van der Waals interaction. The adsorption of nucleobases on H-Si is in the order G > C > A = T > U. The findings of the result demonstrate that H-Si can be used to identify the nucleobases, which can be used for DNA/RNA sequencing in medical science and biotechnology.

New cationic and neutral copper(II) complexes containing 7-hydroxy-4-oxo-4[H]-chromene derived ONO pincer ligands: Synthesis, characterization and in vitro biological evaluations.

New Schiff base ligands are prepared by the condensation of 7-hydroxy-3-formylchromone with semicarbazone and phenyl semicarbazone. The complexation of these ligands with Cu(II) ion is proposed in the light of spectral studies (IR, UV-Vis, 1H NMR, 13C NMR, Mass and ESR). In the complexes 1 and 2, the ligands coordinate to the Cu(II) ion in a neutral fashion via ONO donor atoms. The single crystal XRD studies reveal a slightly distorted square-pyramidal geometry for cationic complex (1) and an octahedral geometry for neutral complex (2). Preliminary biological studies such as DNA and Protein binding are carried out by using absorption and emission titration methods. Observation of intercalative mode of binding with Calf Thymus DNA (CT-DNA) is confirmed by means of viscosity measurements. The micro-environmental changes occurring in Bovine Serum Albumin (BSA) and Human Serum Albumin (HSA) are monitored via three dimensional (3D) fluorescence studies. The compounds ability in inhibiting microbial growth is tested against different pathogens. MCF-7 (human breast cancer) and A549 (human lung carcinoma) cell lines are utilized to check the anticancer potential of the synthesized compounds by using MTT, LDH and NO assays. The results show that complexes 1 and 2 exhibited potent cytotoxic activity over standard drug cisplatin.

An investigation on 3-acetyl-7-methoxy-coumarin Schiff bases and their Ru(ii) metallates with potent antiproliferative activity and enhanced LDH and NO release.

New cyclometallated ruthenium(ii) complexes of 3-acetyl-7-methoxycoumarin-4N-substituted thiosemicarbazones were synthesized and characterized by analytical and spectral techniques. The crystal structures of the ligands H2L1-3 and complexes (1, 2 and 4) were confirmed by X-ray crystallography. The analysis showed that the ligands have undergone C-H activation at the C(4) carbon of the pyrone ring and acted in a tridentate fashion by binding through C, N and S atoms. CT-DNA and protein (BSA/HSA) binding studies were carried out to analyze their interaction with biomolecules. Good binding affinity with DNA was observed with intercalative binding mode, which was further confirmed by EB displacement and viscosity measurement studies. The quenching mechanism with BSA/HSA was found to be static. Three dimensional (3D) fluorescence measurements were carried out to validate the micro environmental changes in the serum albumins. Their antioxidant propensity and antimicrobial study insisted that the compounds displayed good spectrum of activity. Evaluation of their anticancer potential against MCF-7 (human breast cancer) and A549 (human lung carcinoma) cell lines revealed that the complexes exhibited better activity than the ligands and cisplatin. Further, the results of LDH and NO release assays supported the cytotoxic nature of the compounds. The non-toxic nature of the compounds was established by testing against the non-cancerous cell line HaCaT (human normal keratinocyte).

3-Acetyl-8-methoxy-2[H]-chromen-2-one derived Schiff bases as potent antiproliferative agents: Insight into the influence of 4(N)-substituents on the in vitro biological activity.

A series of 3-acetyl-8-methoxycoumarin appended thiosemicarbazones (1-4) was prepared from the reaction of 3-acetyl-8-methoxycoumarin with 4(N)-substituted thiosemicarbazides in a view of ascertaining their biological properties with the change of N-terminal substitution in the thiosemicarbazide moiety. Comprehensive characterization was brought about by various spectral and analytical methods. The molecular structures of all the compounds were determined by single crystal X-ray diffraction analysis. Binding studies with Calf thymus DNA (CT-DNA) and proteins such as Bovine Serum Albumin (BSA) and Human Serum Albumin (HSA) indicated an intercalative mode of binding with DNA and static quenching mechanism with proteins. The compounds cleaved plasmid DNA (pBR322) and acted well as free radical scavengers. A good spectrum of antimicrobial activity was observed against four bacterial and five fungal pathogens. The compounds exhibited profound antiproliferative activity on MCF-7 (human breast cancer) and A549 (human lung carcinoma) cell lines. Assay on human normal keratinocyte cell line HaCaT showed that the compounds were non-toxic to normal cells.

Synchronization of generalized reaction-diffusion neural networks with time-varying delays based on general integral inequalities and sampled-data control approach.

This paper explores the problem of synchronization of a class of generalized reaction-diffusion neural networks with mixed time-varying delays. The mixed time-varying delays under consideration comprise of both discrete and distributed delays. Due to the development and merits of digital controllers, sampled-data control is a natural choice to establish synchronization in continuous-time systems. Using a newly introduced integral inequality, less conservative synchronization criteria that assure the global asymptotic synchronization of the considered generalized reaction-diffusion neural network and mixed delays are established in terms of linear matrix inequalities (LMIs). The obtained easy-to-test LMI-based synchronization criteria depends on the delay bounds in addition to the reaction-diffusion terms, which is more practicable. Upon solving these LMIs by using Matlab LMI control toolbox, a desired sampled-data controller gain can be acuqired without any difficulty. Finally, numerical examples are exploited to express the validity of the derived LMI-based synchronization criteria.