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Using the quartile-based statistical' as this approach is used in the present study approach G-PS-VTEC data of the Lhasa observing station (Geographical Lat. 29.66° N, Geographical Long. 91.10° E) are analysed for six months from July 1, 2019, to December 31, 2019, in the light of eleven major shallow earthquakes (M ≥ 5.0, depth < 30 km) occurred in India, Nepal, and China within a radius of 1500 km assuming it as a center. The results of the analysis show anomalous TEC enhancements of 0.08–15.26 TECU, 1–28 days before the occurrence of these earthquakes. The percentage of TEC enhancements seen before these earthquakes range from 0.74–113.20%. Co-seismic TEC enhancements are also noted for the earthquakes (M = 5, 5.4, 5, 5.3, 5) of August 11, 31, 2019, September 7, 2019, October 27, 2019, and December 9, 2019. The range of co-seismic TEC enhancements is 0.01–4.25 TECU and percentage range of these enhancements is 0.07–31.08%. The post TEC enhancements are observed for the seismic events. The range of post TEC enhancements and percentage enhancements in it are 0.12–6.54 TECU and 1.52–36.41% respectively and the duration of these enhancements is found to vary from 1–21 days. Further, these enhancements in TEC data are also examined in the light of magnetic storms and solar activity and it is found that none of these enhancements are associated with solar activity and magnetic storms. The anomalous days are also confirmed by one more statistical technique. Finally, the possible generation and propagation mechanisms for the observed anomalies are also discussed. [ABSTRACT FROM AUTHOR]

Aim: This article presents a novel approach to automate the segmentation of organ at risk (OAR) for high-dose-rate brachytherapy patients using three deep learning models combined with ensemble learning techniques. It aims to improve the accuracy and efficiency of segmentation. Materials and Methods: The dataset comprised computed tomography (CT) scans of 60 patients obtained from our own institutional image bank and 10 patients from the other institute, all in Digital Imaging and Communications in Medicine format. Experienced radiation oncologists manually segmented four OARs for each scan. Each scan was preprocessed and three models, Double U-Net (DUN), Bi-directional ConvLSTM U-Net (BCUN), and Transformer Networks (TN), were trained on reduced CT scans (240 × 240 × 128) due to memory limitations. Ensemble learning techniques were employed to enhance accuracy and segmentation metrics. Testing and validation were conducted on 12 patients from our institute (OID) and 10 patients from another institute (DID). Results: For DID test dataset, using the ensemble learning technique combining Transformer Network (TN) and BCUN, i.e., TN + BCUN, the average Dice similarity coefficient (DSC) ranged from 0.992 to 0.998, and for DUN and BCUN (DUN + BCUN) combination, the average DSC ranged from 0.990 to 0.993, which reflecting high segmentation accuracy. The 95% Hausdorff distance (HD) ranged from 0.9 to 1.2 mm for TN + BCUN and 1.1 to 1.4 mm for DUN + BCUN, demonstrating precise segmentation boundaries. Conclusion: The proposed method leverages the strengths of each network architecture. The DUN setup excels in sequential processing, the BCUN captures spatiotemporal dependencies, and transformer networks provide a robust understanding of global context. This combination enables efficient and accurate segmentation, surpassing human expert performance in both time and accuracy. [ABSTRACT FROM AUTHOR]

Aim: The goal of this study was to get optimal brain tumor features from magnetic resonance imaging (MRI) images and classify them based on the three groups of the tumor region: Peritumoral edema, enhancing-core, and necrotic tumor core, using machine learning classification models. Materials and Methods: This study's dataset was obtained from the multimodal brain tumor segmentation challenge. A total of 599 brain MRI studies were employed, all in neuroimaging informatics technology initiative format. The dataset was divided into training, validation, and testing subsets online test dataset (OTD). The dataset includes four types of MRI series, which were combined together and processed for intensity normalization using contrast limited adaptive histogram equalization methodology. To extract radiomics features, a python-based library called pyRadiomics was employed. Particle-swarm optimization (PSO) with varying inertia weights was used for feature optimization. Inertia weight with a linearly decreasing strategy (W1), inertia weight with a nonlinear coefficient decreasing strategy (W2), and inertia weight with a logarithmic strategy (W3) were different strategies used to vary the inertia weight for feature optimization in PSO. These selected features were further optimized using the principal component analysis (PCA) method to further reducing the dimensionality and removing the noise and improve the performance and efficiency of subsequent algorithms. Support vector machine (SVM), light gradient boosting (LGB), and extreme gradient boosting (XGB) machine learning classification algorithms were utilized for the classification of images into different tumor regions using optimized features. The proposed method was also tested on institute test data (ITD) for a total of 30 patient images. Results: For OTD test dataset, the classification accuracy of SVM was 0.989, for the LGB model (LGBM) was 0.992, and for the XGB model (XGBM) was 0.994, using the varying inertia weight-PSO optimization method and the classification accuracy of SVM was 0.996 for the LGBM was 0.998, and for the XGBM was 0.994, using PSO and PCA-a hybrid optimization technique. For ITD test dataset, the classification accuracy of SVM was 0.994 for the LGBM was 0.993, and for the XGBM was 0.997, using the hybrid optimization technique. Conclusion: The results suggest that the proposed method can be used to classify a brain tumor as used in this study to classify the tumor region into three groups: Peritumoral edema, enhancing-core, and necrotic tumor core. This was done by extracting the different features of the tumor, such as its shape, grey level, gray-level co-occurrence matrix, etc., and then choosing the best features using hybrid optimal feature selection techniques. This was done without much human expertise and in much less time than it would take a person. [ABSTRACT FROM AUTHOR]

The GPS-based total electron content (TEC) data observed at four low-latitude TEC stations—Lucknow (LCK3), Bangalore (IISC), Hyderabad (HYDE), and Lhasa (LHAZ) are subjected to Quartile-based statistical analysis to study the effect of six major shallow earthquakes (M > 6.0, depth < 30 km) that occurred in and around India in 2017. The results show anomalous enhancements in the TEC data 2–14 days before and 3–15 days after the onset of the earthquakes considered. These pre- and postseismic TEC enhancements are between 1.2–8.7 and 0.7–25.6 TECU, respectively, and percentage TEC enhancements before and after these earthquakes range from 3.82–69.04 and 4.40–95.53%, respectively. The influence of solar activity and magnetic storms on GPS-TEC data have also been examined, and it has been noted that the recorded anomalous TEC enhancements are not associated with these spurious sources except for correlation of TEC enhancements for three with magnetic storms. To confirm the association of observed precursory TEC enhancements occasions with the earthquakes considered in the present analysis probabilities for the pairs of TEC enhancements with the focal depths and precursory times with the distances of epicenters of the earthquakes from the observing stations are computed using t-test. The probabilities for the said pairs were 99.7 and, 70.5% for Lucknow; 47.5 and 98.9% for Bangalore; 95.7 and, 98.5% for Hyderabad; and 71.7 and 99.9% for Lhasa which are fairly large except for the Bangalore TEC observing station for the pair of precursoy time and epicentral distances, confirming the relationship between the TEC enhancements and considered earthquakes. In addition, possible mechanisms for perturbation in the TEC data due to seismic events are also discussed. [ABSTRACT FROM AUTHOR]

Monitoring of the vertical component of VLF electric fields is in progress at Chaumuhan, Mathura observatory (Lat. 27.5° N, Long. 77.68° E) at the frequency 3.012 kHz since 24 March 2011 employing the terrestrial antenna for studying the effect of electromagnetic radiations associated with earthquakes on the atmosphere. The bulk of the data collected for 8 months from February 2016 to October 2016 (except April 2016) have been analyzed in the light of shallow moderate earthquakes (4.9 ≤ M ≤ 6, depth ≤ 20 km) that have occurred in India and around within a radius of 1500 km assuming Mathura as a center. The VLF data obtained for each day is averaged out and its daily variation is compared with the monthly average for the group of eight months considered in the present analysis for identifying the disturbed days. It is found that daily variation exceeds the monthly mean, 1–23 days before the onset of the earthquakes in India and around within the radius of 1500 km. The influence of magnetic storms, lightning, local building noises, and seismic activities are studied on these VLF amplitude enhancements and it is found that they are not related to these spurious sources but are associated with the moderate seismic events that have occurred during the period of observations. Further, the generation and transmission mechanisms of these signals are also discussed. [ABSTRACT FROM AUTHOR]

Measurements of amplitude of vertical components of very low frequency (VLF) electric field emissions have been in progress at Chaumuhan, Mathura (27.5°N, 77.68°E), Uttar Pradesh, India, at the frequency of 3.012 kHz using a borehole antenna since 24 March 2011. In the present study, we have statistically analysed the VLF data from 1 January to 31 July 2015 using the mean (m) and standard deviation (s) around the mean (m ± 2s) criterion with respect to two major earthquakes (M = 7.8, 7.3) and their aftershocks that occurred on 25 April and 12 May 2015 in Khudi and Kodari regions of Nepal respectively. Results of the analysis show a spiky enhancement above the m + 2s line in the daily variation of the normalized VLF data, 7-14 days before the onset of main shocks of these earthquakes. These anomalous enhancements in the normalized values of amplitude are examined in light of various other possible causative sources such as magnetic storms, local lightning, solar flares and solar eclipse, rainfall, wind speed, temperature and pressure of the atmosphere. It was found that the VLF amplitude anomalies are not related to these sources. Further, we have developed a theoretical model for generation and propagation mechanisms of VLF emissions associated with the said earthquakes and their aftershocks by assuming an ensemble of elementary radiators randomly oriented and distributed in space and time in the preparation zones of these earthquakes. The computed electric field from the model is in good agreement with the observations. [ABSTRACT FROM AUTHOR]

• Four new copper(II) halobenzoate complexes have been reported for the first time. • Detailed spectroscopic characterization (FT-IR and EPR) have been done. • Structural studies have been achieved through SCXRD. • Predominant role of non-covalent interactions such as halogen and hydrogen bonding have been estalished. • Molcular docking analyses revealed the potency of all complex as antimicrobial agnets than standard drugs. In this work, we reported four new copper(II) halo-benzoate complexes (2-chloro-4-nitrobenzoate (2-Cl-4-NO2-BZ), 3,5-DICBZ, 2-chloro-5-nitrobenzoate (2-Cl-5-NO2-BZ), 3,5-difluoro benzoate (3,5-DIFBZ), and 3,5-dichlorobenzene (3,5-DICBZ) respectively in complexes 1–4) with N,N,N',N'- tetramethylethylene diamine (temed) N-donor ligand in order to study the interesting coordination features and biological evaluation of such complexes under ambient reaction conditions. All the complexes 1–4 were characterized by elemental analyses, and spectroscopic techniques, including FT-IR, UV–vis, and EPR etc. Single crystal X-ray structure determination (SCXRD) of complexes revealed the distorted octahedral geometry in all complexes. Notably, the halobenzoate ligands exhibited a bidentate chelation mode in complexes 1 and 2 , while they showed a monodentate mode in complex 3. In complex 4 , the carboxylate ligand exhibited both monodentate as well as bidentate coordination. Furthermore, detailed packing analyses of complexes 1–4 highlighted the significance of halogen bonding in lattice stabilization besides hydrogen bonding and π∙∙∙π interactions as evidenced by Hirshfeld surface analyses and crystal analysis. Moreover, packing analyses displayed that complex 1 exhibited a layered or wave-like arrangement, while complex 2 featured a helical arrangement supported by a supramolecular halogen-bonded network guided by Cl∙∙∙O interactions. Complex 3 displayed a zig-zag layered arrangement with a stacking topology, and Complex 4 showcased a ribbon-like arrangement stabilized by F∙∙∙F and Cl∙∙∙Cl halogen bonding interactions. Furthermore, sigma hole on halogen atoms has also been examined (which play an important role in halogen bonding) by electrostatic-potential isosurfaces. In order to exploit the biological efficacy of complexes 1–4 owing to the inherent biological activity of copper metal, molecular docking analyses against gram +ve bacteria i.e. S. epidermidis (PDB ID; 8DO6), B. subtilis (1QD9), as well as two gram -ve bacteria, namely, P. aeruginosa (5WZE) and S. dysenteriae (1DM0), have also been carried out. Interestingly, values of docking scores and inhibition constant of all complexes 1–4 (with a maximum binding score (inhibition constant) of -9.8 kcal/mol (0.063 µMol) in 1 against 8DO6 and 1DM0) revealed higher biological efficacy than that of standard drugs. [ABSTRACT FROM AUTHOR]

Highlights • 25% deficit irrigation water (45 mm) when compared to normal followed practice of 60 mm produced similar yield. • 750 m3 water per hectare was saved by application of 45 mm irrigation at five growth stages of wheat. • Reducing water by upto 50% (30 mm) once at any of the five growth stages produced statistically similar yield. • The treatment where 750 m3 water was saved per hectare (75%IAS), was the most remunerative option in addition to saving of cost on inputs. Abstract Wheat is the second most important food crop in India and world. One of the major difficulties faced in the wheat growing regions is the depletion of water resources at an alarming rate. This study was conducted to test the hypothesis that the use of the reduced amount of irrigation water would maintain the grain yield of popular Indian wheat variety HD2967. Water use, crop yield and water use efficiency of wheat were evaluated for three consecutive years under thirteen different irrigation treatments. Highest yield (5372.4 kgha−1) was recorded when crop was irrigated with full irrigation (60 mm of water at all five critical crop growth stages); which were statistically at par to yields recorded under 25% deficit irrigation (45 mm) at all growth stages. The treatment with 50% irrigation (30 mm) at all five growth stages although saved 50% water, yield penalty was also significant (4788.1 kgha−1 = 10.9% loss). Treatments with normal recommended practice (60 mm) have achieved lower water use efficiency (WUE) values (1.88 kg m-3) whereas, 25% deficit irrigation i.e. 45 mm at all five stages recorded significantly higher WUE (2.23 kgm-3) in sandy loam soils. The treatment where a total of 750 m3 water was saved per hectare was the most remunerative option in addition to saving of cost on water, electricity and labour. Adoption of 45 mm irrigation at all crop growth stages can enhance both irrigation water use efficiency without any yield penalty and can be adopted as a water saving mechanism in the regions of depleting water resources. [ABSTRACT FROM AUTHOR]

Graphical abstract New copper(II) complexes containing the non-steroidal anti-inflammatory drug niflumic acid as ligand have been synthesized and characterized. Cytotoxic effects of the complexes on tumoral human cell lines have also been evaluated. Highlights • Five new copper(II)-niflumate complexes have been synthesized and characterized. • Their structures have been determined by X-ray diffraction and DFT calculations. • Cytotoxic effects of the complexes on tumoral human cell lines have been evaluated. • The niflumate coordination mode affects cytotoxicity against the cell line HT-144. Abstract Five new copper(II) niflumate complexes, [Cu(en) 2 (nif) 2 ], 1 , [Cu(unsym- dmen)(nif) 2 ], 2 , [Cu(pn) 2 (nif) 2 ][Cu(pn) 2 (H 2 O) 2 ](nif) 2 3 , [Cu(β- pic) 2 (nif) 2 ], 4 , [Cu(γ- pic) 2 (nif) 2 ] 5 (where en = ethylenediamine, pn = propan-1,3-diamine, unsym-dmen = 1,1-dimethyl-ethylenediamine, β -pic = 3-methylpyridine, γ -pic = 4-methylpyridine, nif = niflumate) have been synthesized by using appropriate starting materials and methanol-water (4:1 v/v) as solvent. All the above synthesized complexes 1 – 5 have been characterized by spectroscopic methods (UV–Vis, FT-IR, and EPR). The structures of complexes 1 , 3 and 5 have been unambiguously determined by single crystal X-ray structure determination which clearly revealed that these complexes are mononuclear complexes. The structure of complex 4 has been optimized by DFT calculations. In all complexes 1 – 5 , niflumate ligand shows direct coordination to central copper(II) ion leading to covalent character of these complexes, although the complex 3 also contains cationic moiety [Cu(p n) 2 (nif) 2 ]2+ and two nifumate ions. The ability of all the complexes to show cytotoxicity against human cancer cell lines has also been evaluated. [ABSTRACT FROM AUTHOR]

Graphical abstract Four new silver(I) naphthalenedisulfonate complexes with heterocyclic N-donor ligands have been synthesized and characterized through spectroscopic techniques and X-ray crystallography. Biological studies indicate they have antibacterial efficacy against both gram positive and gram negative bacterial strains. Abstract Four new silver(I) naphthalenedisulphonate complexes, [Ag 2 (1,5-nds) (β-Pic) 4 ]·2H 2 O (1), [Ag 2 (1,5-nds)(γ-Pic) 4 ]·6H 2 O (2), [Ag 2 (2,6-nds) (β-Pic) 4 ] (3) and [Ag 2 (2,6-nds) (γ-Pic) 4 ]·2H 2 O (4) have been synthesized using appropriate starting materials at ambient temperature and normal reaction conditions and fully characterized by spectroscopic methods (FT-IR, NMR). The structures of all the four complexes were determined using single crystal X-ray diffraction techniques and a detailed analysis of the role of weak non-covalent interactions in the solid state (hydrogen bonds, argentophylic interactions, π⋯π interactions) were investigated. Antibacterial activities of all complexes have been evaluated, indicating their high efficacy against both gram positive and gram negative bacterial strains. [ABSTRACT FROM AUTHOR]

Abstract Two new copper(II) complexes; [Cu(temed)(p-nitro-cinnamate) 2 ] (1), [Cu(temed)(p-methoxy-cinnamate) 2 ] (2), where temed = N,N,N′,N'-tetramethylethylenediamine, have been synthesized by reacting appropriate starting materials using methanol-water (4:1 v/v) as solvent at room temperature. Both newly synthesized copper(II) cinnamate complexes have been characterized on the basis of elemental analyses, spectroscopic techniques (FT-IR, UV–visible, EPR) and single crystal X-ray structure determination. X-ray structure determination of both complexes revealed the existence of neutral structure of both complexes. p -Nitrocinnamate and p-methoxycinnamte exhibited similar (asymmetric chelating) coordination mode of carboxylate ligand towards copper(II) metal centre. Various non-covalent intermolecular interactions such as C-H∙∙∙O have also been observed that play an important role in crystal lattice stabilization of complexes 1 and 2. The EPR spectroscopy on the basis of axial symmetry of g tensor components suggested tetragonally elongated octahedral geometry of the complexes which is consistent with X-ray structure determination. Graphical abstract Image Highlights • Successful synthesis of two new copper(II) cinnamate complexes. • Crystal structures revealed neutral structure of both complexes. • p -Nitrocinnamate and p -methoxycinnamate showed bidentate chelation. • Involvement of extensive π∙∙∙π stacking interactions between aromatic rings. • Tetragonally elongated octahedral geometry revealed from EPR measurements. [ABSTRACT FROM AUTHOR]

The reaction of the copper(II) diclofenac complex [Cu( dicl ) 2 (H 2 O) 2 ] ( 1 ) ( dicl  = deprotonated diclofenac (H dicl )) with the chelating N-donor ligands ethylenediamine ( en ), propan-1,3-diamine ( pn ), unsymmetrical dimethylethylene-diamine ( unsym-dmen ) and N , N , N ′, N ′-tetramethylethylene-diamine ( temed ) in methanol-water (4:1 v/v) yielded the novel copper(II) complexes [Cu( en ) 2 (H 2 O) 2 ]( dicl ) 2 ·2H 2 O ( 2 ), [Cu( pn ) 2 (H 2 O) 2 ]( dicl ) 2 ·2H 2 O ( 3 ), [Cu( unsym-dmen ) 2 (H 2 O)]( dicl ) 2 ·H 2 O ( 4 ) and [Cu( temed )( dicl ) 2 ] ( 5 ), respectively. All the synthesized complexes were characterized by spectroscopic (UV–vis, FT-IR) methods. The structures of complexes 2 , 3 and 5 were unambiguously determined by single-crystal X-ray crystallography. X-ray structures of complexes clearly revealed the ionic structure of complexes 2 , 3 and the covalent structure of complex 5 . The geometry of complex 4 was optimized by Density Functional Theory (DFT) calculations. The ability of the complexes 1–5 to bind to calf-thymus DNA was monitored in vitro by diverse techniques (UV–vis spectroscopy, cyclic voltammetry, viscosity measurements) and via competitive studies with ethidium bromide. The interaction of complexes 1–5 with bovine serum albumin was studied in vitro by fluorescence emission spectroscopy and the corresponding binding constants were calculated. The biological behavior of complexes 1–5 was compared with previously reported Cu(II), Mn(II) and Ni(II) complexes of diclofenac. [ABSTRACT FROM AUTHOR]

Two transition metal complexes containing copper (II) ion, dye methyl red (H-MR) and nitrogen donor ligands β/γ-picoline (β/γ-pic) have been synthesized for the first time using appropriate starting materials in methanol-water (4:1 v/v) as solvent and characterized by spectroscopic methods (UV–Vis, FT-IR) and thermogravimetric analyses. The crystal structures of both complexes have been unambiguously determined by single crystal X-ray analysis as [Cu(MR) 2 (β-pic) 2 ] for 1 and [Cu(MR) 2 (γ-pic) 2 (MeOH) 0.5 (H 2 O) 0.5 ]∙0.5MeOH∙1.5H 2 O for 2 . Whereas in complex 1 Cu(II) coordinated by carboxylate oxygen atoms of two MR and nitrogen atoms of two β-pic molecules adopts an almost ideal square planar geometry, in complex 2 Cu(II) additionally coordinated by methanol/water exhibits a distorted square pyramidal structure. Both complexes are packed in layers stabilized by intermolecular C/O H⋯O hydrogen bonds. DFT calculations provided insight into the existence of the six possible relevant complexes. The relative stabilities are in the order Cu(MR) 2 (γ-pic) 2 (H 2 O) 2w  ≈ Cu(MR) 2 (β-pic) 2 (H 2 O) 1w  > Cu(MR) 2 (γ-pic) 2 (MeOH) 2m  ≈ Cu(MR) 2 (β-pic) 2 (MeOH) 1m  » Cu(MR) 2 (γ-pic) 2 2b  ≈ Cu(MR) 2 (β-pic) 2 1 , suggesting the significant role of solvent's coordination in enhancing the thermodynamic stability of metal coordination complexes. [ABSTRACT FROM AUTHOR]

Cadmium, an extremely toxic heavy metal, is of a major public health concern and its efficient removal from the environment is a real challenge. This work aims for a deep understanding of stable cadmium(II) chelation with a tridentate ligand to form complex salts being stabilized by cation–anion hydrogen bonding non-covalent interactions in addition to electrostatic interactions. Three new Cd(II) complexes, [Cd(H 2 O) 6 ]( pic ) 2 ·2H 2 O 1 , [Cd(N- hyden ) 2 ]( pic ) 2 2 , [Cd(N- hyden ) 2 ]( pnb ) 2 3 , (where N- hyden  = N-(hydroxyethyl)ethylenediamine, H pic  = picric acid and H pnb  = p-nitrobenzoic acid) using the appropriate acids in the absence and presence of the tridentate N- hyden ligand have been synthesized and fully characterized by elemental analyses, thermogravimetric analyses and spectroscopic (FT-IR, NMR) techniques. The exact ionic structures of complexes 1 – 3 have been unambiguously determined using single crystal X-ray diffraction studies. They comprise octahedrally surrounded cationic Cd(II) centers, [Cd(H 2 O) 6 ] 2+ in 1 and [Cd(N- hyden ) 2 ] 2+ in 2 and 3 , together with the counter anions pic / pnb , which are stabilized by a mutual interplay of various hydrogen bonding interactions. [ABSTRACT FROM AUTHOR]

Three new anhydrous [copper(II)(N -hyden ) 2 ](o-/m-/p-methoxybenzoate) 2 complexes, 1 – 3 , (where N -hyden = N-(hydroxyethyl)ethylenediamine) have been prepared by the dropwise addition of N -hyden to the hydrated copper(II) o-/m-/p-methoxybenzoate compounds suspended in a methanol–water (4:1 v/v) mixture, followed by evaporation of the resulting solution at room temperature. They have been characterized by elemental analyses, spectroscopic techniques (FT-IR and UV–Vis), conductance measurements and magnetic susceptibility studies. Single crystal X-ray structure determination showed that complexes 1 and 3 crystallize in the monoclinic system with space group P 2 1 / c , while complex 2 crystallizes in the triclinic system with space group P 1 ¯ ; all in centrosymmetric space groups. The X-ray analysis of complexes 1 – 3 clearly revealed their ionic structures, consisting of one complex cation, [Cu(N -hyden ) 2 ] 2+ , and two respective substituted arylcarboxylate (o-/m-/p-methoxybenzoate) anions. The Cu(II) center in each complex is octahedrally coordinated to two tridentate N -hyden ligands, in which two nitrogen and one oxygen atoms of two N -hyden ligands are coordinated in trans geometries. The crystal lattices in complexes 1 – 3 are stabilized by non-covalent interactions such as N–H⋯O, O–H⋯O hydrogen bonding and C–H⋯π interactions. [ABSTRACT FROM AUTHOR]

Copper(II) hydrogen ferulate was reacted with ethylenediamine ( en ) in methanol–water (4:1) mixture, yielding single crystals of complex [Cu( en ) 2 (H 2 O) 2 ](fer) ( 1 ), (where fer = ferulate dianion derived from ferulic acid = H 2 ​fer by loss of two protons) which was unequivocally characterized by physicochemical and single crystal X-ray structural studies. Copper(II) metal center is octahedrally surrounded by two en and two water molecules in a trans-geometry while one ferulate dianion is present as discrete unit without being coordinated to metal center. Anionic layers of ferulate dianions are arranged in between cationic layers of [Cu( en ) 2 (H 2 O) 2 ] 2+ , forming a sandwich type of arrangement which is stabilized by interplay of N–H…O, O–H…O hydrogen bonds and electrostatic forces. Stabilizing effect of larger [Cu( en ) 2 (H 2 O) 2 ] 2+ cation induces the formation of naturally occurring and biologically important ferulate as dianionic species which is unprecedented, but also supported by DFT calculations. [ABSTRACT FROM AUTHOR]

Three novel coordination complexes of copper(II) with 2,4,5-trichlorophenoxyacetate [Cu (γ-pic ) 3 (L) 2 ]·H 2 O 1 , [ trans -Cu( en ) 2 (L) 2 ]·2H 2 O 2 and [Cu 2 (H 2 tea ) 2 (L) 2 ]·2H 2 O 3 , where L = 2,4,5-trichlorophenoxyacetate, γ -pic = γ -picoline, en = ethylenediamine, H 2 tea = monodeprotonated triethanolamine, were synthesized by addition of γ -picoline/ethylenediamine/triethanolamine, respectively, to the hydrated Cu(2,4,5-trichlorophenoxyacetate) 2 suspended in methanol-water (4:1, v/v). The newly synthesized complexes have been characterized by elemental analyses, spectroscopic techniques (UV–Vis and FT-IR), magnetic moment determination, molar conductance studies, TGA and single crystal X-ray diffraction method. The structure determination revealed neutral nature of complexes in all the three cases, with different coordination geometry around the copper(II) metal centre depending upon nature of the N- or N,O-donor ligands. Hydrogen bonding network i.e. O–H⋯O and C–H⋯O in complexes 1 , 3 and N–H⋯O, and O–H⋯O in complex 2 stabilizes crystal lattice in copper(II) complexes besides other non-covalent interactions. [ABSTRACT FROM AUTHOR]

Two new copper(II) complexes of composition [Cu( en ) 2 (H 2 O) 2 ](2-phenoxybenzoate) 2 ·H 2 O, 1 and [Cu( en ) 2 (H 2 O)](diphenylacetate) 2 ·3H 2 O, 2 (where en = ethylenediamine) have been synthesized, characterized by elemental analyses, spectroscopic techniques (UV–vis and FT-IR), magnetic moment determination and conductance measurements and their structures have been unequivocally confirmed by single crystal X-ray analysis. Both complexes crystallize in the monoclinic crystal system with space groups C 2/ c , for 1 and P 2 1 / n , for 2 . Complex 1 exhibits a distorted octahedral geometry with four nitrogen atoms of chelating en ligands and two oxygen atoms of water molecules coordinated to central Cu(II) ion, whereas complex 2 shows a square pyramidal geometry around copper(II) with four nitrogen atoms of chelating en ligands and one oxygen atom of water molecule. Crystal structures of both complexes are stabilized by collective interplay of various non-covalent interactions such as O–H⋯O, N–H⋯O and C–H⋯π interactions, besides electrostatic attraction. DFT optimization studies clearly showed that complex 2 is quite stable with square pyramidal geometry than expected octahedral geometry. Both complexes show potential antibacterial activities against gram positive and gram negative bacteria. [ABSTRACT FROM AUTHOR]

A new anionic copper(II) complex, (MeImH) 2 [Cu(pfbz) 4 ] ( 1 ) where, MeImH = 2-methylimidazolium and pfbz = pentafluorobenzoate has been isolated by reacting copper(II) sulfate pentahydrate, pentafluorobenzoic acid and 2-methylimidazole in ethanol: water mixture in 1:2:2 molar ratio. This complex 1 has been characterized by elemental analysis, thermogravimetric analysis, spectroscopic techniques (UV-Vis, FT-IR) and conductance measurements. The complex salt crystallizes in monoclinic crystal system with space group C 2/c. Single crystal X-ray structure determination revealed the presence of discrete ions: [Cu(pfbz) 4 ] 2- anion and two 2-methylimidazolium cation (C 4 H 7 N 2 ) + . The crystal lattice is stabilized by strong hydrogen bonding and F⋯F interactions between cationic-anionic and the anionic-anionic moieties respectively, besides π-π interactions. [ABSTRACT FROM AUTHOR]

The reaction of hydrated copper(II) 3-chloro/bromobenzoates with β / γ -picoline in a methanol:water mixture (4:1 v/v) yielded four monomeric complexes, [Cu(3-chlorobenzoate) 2 ( β -picoline) 2 ] ( 1 ), [Cu(3-chlorobenzoate) 2 ( γ -picoline) 2 (H 2 O)] ( 2 ), [Cu(3-bromobenzoate) 2 ( β -picoline) 2 (H 2 O)] ( 3 ) and [Cu(3-bromobenzoate) 2 ( γ -picoline) 2 )] ( 4 ). The newly synthesized complexes have been characterized by elemental analyses, spectroscopic methods (FT-IR, UV–Vis), TGA and single crystal X-ray structure determination. Crystallographic investigations revealed that all the copper(II) 3-halobenzoates complexes with β -/ γ -picoline ligands are monomeric in nature, in contrast to polymeric copper(II) 2-halobenzoate complexes in the presence of similar N-donor ligands. Various non-covalent interactions, like O–H⋯O, C–H⋯O, C–H⋯π and anion ⋯π, have been observed to play a decisive role in the stabilization of the crystal lattices in all the complexes. All the newly synthesized copper(II) complexes show significant antibacterial activity against gram negative and gram positive bacteria. [ABSTRACT FROM AUTHOR]

A new hybrid inorganic-organic compound [Cu( Hdien ) 2 (H 2 O) 2 ]( pnb ) 4 ·4H 2 O ( 1 ) (where pnb = p -nitrobenzoate), in which the tridentate ligand diethylenetriamine ( dien ) shows an unusual coordination behavior acting as a bidentate ligand when present in its monoprotonated form ( Hdien + ) has been synthesized by the reaction of copper(II) p -nitrobenzoate and slight excess of dien in methanol-water mixture (4:1v/v). Re-crystallization of the violet precipitated product from hot water gave single crystals suitable for X-ray diffraction studies. The newly synthesized compound 1 has been characterized by spectroscopic techniques (UV–Vis, FT-IR, EPR), and theoretical methods (DFT and MRCI/SORCI). Single crystal X-ray structure determination revealed the existence of the cationic species [Cu( Hdien ) 2 (H 2 O) 2 ] 4+ , four p -nitrobenzoate as counter anions and four water molecules are present as solvent of crystallization. Packing analyses of title compound as well as of the structurally similar [Cu( en ) 2 (H 2 O) 2 ]( pnb ) 2, 2 has shown similarities in the crystalline architecture that both hybrid inorganic-organic compounds is stabilized by various non-covalent interactions such as N-H⋯O, C-H⋯O, O-H⋯O etc. [ABSTRACT FROM AUTHOR]

Two new copper(II) complexes [Cu(β-pic) 4 (2-Cl-5-nitrobenzenesulfonate) 2 ](CH 3 OH) ( 1 ) and [Cu(γ-pic) 4 (2-Cl-5-nitrobenzenesulfonate) 2 ] ( 2 ) have been synthesized by reacting appropriate starting materials in methanol:water (v/v 4:1). Both newly synthesized complexes have been characterized on the basis of elemental analyses, spectroscopic techniques (FT-IR, UV–Vis, EPR) and single crystal X-ray structure determination (complex 1 ). The structural analysis of complex 1 revealed the existence of unusual coordination behavior of arylsulfonate towards copper(II) center in presence of heterocyclic N-donor ligands resulting in elongated octahedral geometry around the metal. The EPR spectroscopy of complexes 1 and 2 unambiguously proved a similar coordination of four picolines in Cu(II) xy plane. Antimicrobial studies of both the complexes 1 and 2 were performed against Gram positive, MRSA (Methicillin-Resistant Staphylococcus aureus ) as well as Gram negative ( Escherichia coli , Klebsiella pneumoniae ) bacteria. The activity was investigated by using both Agar well diffusion as well as MIC assay. Both the complexes show significant bactericidal activity against all the pathogenic strains in comparison to ampicillin, a broad spectrum antibiotic against Gram positive and Gram negative bacteria. [ABSTRACT FROM AUTHOR]

Pernicious anemia is a common cause of vitamin B12 deficiency. Here, we discuss a case of a young woman who presented with severe anemia along with a history of iron deficiency anemia. After a review of her clinical presentation and laboratory data, we identified an autoimmune hemolytic anemia and a concomitant pernicious anemia. The concurrence of both these hematological diagnoses in a patient is rare. [ABSTRACT FROM AUTHOR]

Background and Aims: Swapping of the endotracheal tube with laryngeal mask airway (LMA) before emergence from anaesthesia is one of the methods employed for attenuation of pressor response at extubation. We decided to compare the placement of ProSeal™ LMA (PLMA) before endotracheal extubation versus conventional endotracheal extubation in controlled hypertensive patients scheduled for elective surgeries under general anaesthesia. Methods: Sixty consenting adult patients were randomly allocated to two groups of thirty each; Group E in whom extubation was performed using standard technique and Group P in whom PLMA was inserted before endotracheal extubation (Bailey manoeuvre). The primary outcome parameter was heart rate (HR). The secondary outcomes were systolic, diastolic and mean blood pressure (MBP), electrocardiogram, oxygen saturation and end-tidal carbon dioxide. Two-tailed paired Student's t-test was used for comparison between the two study groups. The value of P < 0.05 was considered as statistically significant. Results: The patient characteristics, demographic data and surgical procedures were comparable in the two groups. A statistically significant decrease was observed in HR in Group P as compared to Group E. Secondary outcomes such as systolic, diastolic and MBP depicted a statistically insignificant difference. Conclusion: Bailey manoeuvre was not effective method to be completely relied upon during extubation when compared to standard extubation. [ABSTRACT FROM AUTHOR]

Using metal ions thallium(I), copper(II), silver(I) and lead(II) and ligand 2-chloro-5-nitrobenzenesulfonate( cnb ), four new metal complexes [Tl( cnb )] n ( 1 ), [Cu(en) 2 (H 2 O) 2 ]( cnb ) 2 .2H 2 O( 2 ), where en = ethylenediamine, [Ag( cnb )] n ( 3 ) and [Pb( cnb ) 2 ] n ( 4 ) have been synthesized and characterized by elemental analyses, spectroscopic methods (FT-IR, multinuclear NMR), single crystal X-ray structure analyses (except 4 ) and TGA analyses. Complexes 1 and 3 crystallize in monoclinic crystal system in P 2 1 / c space group having unit cell dimensions, a = 13.849(2) Å, b = 9.449(2) Å, c = 7.506(2)Å, β = 105.3°, V = 947.1 Å 3 , Z = 4 and a = 15.197(13)Å, b = 5.136(4)Å, c = 24.058(18)Å, β = 106.86°, V = 1797.1 Å 3 , Z = 4 respectively. Complex 2, crystallizes in triclinic crystal system with P I ¯ having unit cell parameters; a = 6.888 Å, b = 7.835 Å, c = 13.227 Å, α = 80.20°, β = 83.15°, γ = 78.18°, V = 945.6 Å 3 , Z = 1. X-ray structure determination revealed that complexes 1 and 3 are polymeric in nature, whereas complex 2 has ionic structure. Remarkably, cnb ligand is coordinating through sulfonato oxygen atoms and nitro oxygen atoms in thallium complex but coordinates through sulfonato oxygen atoms and chloro group in silver complex, thereby showing the flexible/versatile coordinating behaviour of anionic ligand. This is unusual. [ABSTRACT FROM AUTHOR]

The coordination behavior of 2-chloro-4-fluorobenzoate and 2,4-dichlorobenzoate ligands towards copper(II) ion were investigated in the presence of different nitrogen ligands. Four new copper(II) complexes, [trans-Cu(2-Cl-4-FC 7 H 3 O 2 ) 2 (β-pic) 2 ] 1 , [trans-Cu(en) 2 (H 2 O) 2 ](2-Cl-4-FC 7 H 3 O 2 ) 2 , 2 , [trans-Cu(2,4-Cl 2 C 7 H 3 O 2 ) 2 (β-pic) 2 (H 2 O) 2 ], 3 and [trans-Cu(en) 2 (H 2 O) 2 ](2,4-Cl 2 C 7 H 3 O 2 ) 2 ·2H 2 O, 4 , (where β-pic = β-picoline, en = ethylenediamine) were synthesized by addition of β-picoline/ethylenediamine to the respective hydrated copper(II) arylcarboxylate suspended in methanol–water (4:1) mixture at room temperature. The newly synthesized complexes have been characterized by elemental analyses, TGA, spectroscopic techniques (FT-IR and UV–Vis), conductance, magnetic susceptibility studies. Single-crystal X-ray structure determination of the complexes revealed the presence of neutral structure in complexes 1 and 3 whereas complexes 2 and 4 possess ionic structure consisting of complex cation [trans-Cu(en) 2 (H 2 O) 2 ] 2+ and two 2-chloro-4-fluorobenzoate/2,4-dichlorobenzoate as counter anions. The crystal lattice in these copper(II) complexes is stabilized by various non-covalent interactions such as N H…O, O H…O hydrogen bonds and other weaker interactions including C H…π, C H…halogen and halogen…halogen ones. A comparison of non-covalent interactions in four copper(II) complexes is also discussed. [ABSTRACT FROM AUTHOR]

Two new copper(II) complexes [Cu(L 1 ) 2 (TEMED)] ( 1 ) and [Cu(L 2 ) 2 (TEMED)] ( 2 ) (L 1 = 4-chloro-2-nitrobenzoate, L 2 = 5-chloro-2-nitrobenzoate, TEMED = N,N,N′,N′-tetramethylethylenediamine) have been obtained by the addition of TEMED to hydrated Cu(II) benzoates, in methanol–water (4:1, v/v) mixture. The newly synthesized complexes have been characterized by elemental analyses, spectroscopic techniques (UV–Vis, FT-IR, EPR), magnetic moment determination, thermogravimetric analyses, and single-crystal X-ray diffraction analysis. Both complexes 1 and 2 adopt monoclinic crystal structures (space group C 2/ c , Z = 4) and exhibit a distorted square planar coordination geometry around Cu(II) centers. Detailed packing analyses of complexes 1 and 2 have revealed that C–H⋯π interactions in complex 1 and C–Cl⋯π interactions in complex 2 stabilize the crystal lattice. In addition, the structures are influenced by weak C–H⋯O hydrogen bonding intermolecular interactions involving both nitro and carboxylate O atoms. EPR measurements showed the presence of different environment around Cu 2+ in 1 and 2 . [ABSTRACT FROM AUTHOR]

Three new copper(II) complexes trans-[Cu(β-pic) 2 (H 2 O) 2 (5-chloro-2-nitrobenzoate) 2 ] 1 , trans-[Cu(γ-pic) 2 (5-chloro-2-nitrobenzoate) 2 ], 2 and [trans-Cu(en) 2 (H 2 O) 2 ](5-chloro-2-nitrobenzoate) 2 ·2H 2 O, 3 (where β-pic = β-picoline, γ-pic = γ-picoline and en = ethylenediamine) were prepared by the addition of β-pic, γ-pic and en , respectively, to the hydrated copper(II) 5-chloro-2-nitrobenzoate, suspended in methanol–water mixture (4:1, v/v). The newly synthesized complexes have been characterized by elemental analyses, TGA, spectroscopic techniques (FT-IR, UV–Vis and EPR), conductivity measurements, magnetic susceptibility studies and single crystal X-ray structure determination. Complex 1 crystallizes in monoclinic crystal system with P 2 1 / c space group whereas the complexes 2 and 3 crystallizes in triclinic crystal system with P 1 ¯ space group. Single crystal X-ray structure determination revealed the presence of elongated octahedral geometry in all three complexes. Cu(II) center is covalently coordinated by two 5-chloro-2-nitrobenzoate, two β-pic moieties and two water molecules in complex 1 , two bidentate 5-chloro-2-nitrobenzoate and two γ-pic moieties in complex 2 . In complex 3 , the copper ion is coordinated to two chelating en ligands, two water molecules; with two 5-chloro-2-nitrobenzoate as counter anions and two water molecules of crystallization. The crystal lattice in complexes 1 – 3 is stabilized by an intricate network of hydrogen bonding interactions (C–H…O, O–H…O in complex 1 , C–H…O in complex 2 and O–H…O, N–H…O and C–H…O in 3 ). Besides this, π…π stacking interactions in complex 1 and C–H…π interactions in complex 2 also contribute towards stability of the crystal lattice. [ABSTRACT FROM AUTHOR]

Reaction of hydrated copper(II) 2-chloro-benzoate with β-/γ-picoline in methanol: water mixture (4:1 v/v) yielded polymeric [Cu(2-chlorobenzoate) 2 (β-picoline) 2 (μ-H 2 O)] n ; 1 and monomeric [Cu(2-chlorobenzoate) 2 (γ-picoline) 2 (H 2 O)]; 2 . The newly synthesized complexes have been characterized by elemental analyses, FT-IR spectroscopy, UV–Visible spectroscopy, TGA and single crystal X-ray structure determination. X-ray crystallographic analysis revealed that both complexes crystallize in the monoclinic crystal system with space group and unit cell dimensions: C 2/ c ; a = 51.71 Å, b = 10.58 Å, c = 10.02 Å and β = 100.5° for 1 and P 2 1 / c ; a = 11.81 Å, b = 16.33 Å, c = 13.79 Å and β = 90.77° for 2 . Whereas in 1 the presence of constituent and mediating water molecules running along a -axis gives rise to 1-dimensional zig-zag polymer chains, in complex 2 , the presence of square pyramidal arrangement of ligands around copper(II) center results in monomeric structure. Various non-covalent interactions like O H⋯O, C H⋯O and C H⋯л have been observed to play a decisive role in the stabilization of crystal lattices in both complexes. [ABSTRACT FROM AUTHOR]

Rice-wheat is the predominant cropping system and contributes more than 70% of food grain production in India. However, major problem in this system is depletion and deterioration of water resources. Therefore, efforts must be focussed on reversing the trend in water resources depletion by adopting efficient irrigation technologies. The prevalent irrigation methods are less efficient due to more water losses through leaching and evaporation. Micro irrigation can be an effective tool for improving water use efficiency. The study was carried out with an objective of improving the WUE in rice-wheat cropping system with four irrigation methods in wheat crop viz check basin, drip, sprinkler and drip+rainport and three irrigation systems in rice (check basin, drip and sprinkler) at Indian Institute of Wheat and Barley Research, Karnal during 2012-13 and 2013-14. Irrigation treatments significantly affected the grain yield of both the crops. The highest grain yield of wheat (5752 kg ha-1) was obtained in check basin irrigation during 2012-13 followed by drip+rainport (5614 kg ha-1). However, the WUE of check basin method was minimum (1.32 kg m-3). During 2013-14, highest yield was obtained in drip+rainport (5545 kg ha-1) followed by drip irrigation (5475 kg ha-1) with the WUE of 1.57 and 1.55 kg m-3 respectively. In rice, significant higher grain yield (4028 and 4683 kg ha-1) was recorded in drip followed by sprinkler irrigation. The study concludes the maximum WUE in wheat under drip+rainport treatment and in rice it was under drip irrigation treatment. [ABSTRACT FROM AUTHOR]

Three new hybrid inorganic–organic compounds of silver(I), Ag 2 (2,6-nds), 1 , lead(II), [Pb(2,6-nds)·H 2 O] n , 2 and copper(II), [Cu(phen) 3 ](2,6-nds)·11H 2 O, 3 , have been synthesized by reacting appropriate reactants in aqueous medium. All the three compounds were characterized on the basis of elemental analyses, spectroscopic techniques (FT-IR, NMR, EPR and NIR-Vis-UV), thermogravimetric analyses and X-ray powder diffraction studies. Single crystal X-ray structure determination of compound 2 ( Monoclinic, P 2 1 / c ) revealed a polymeric structure in which lead(II) is seven coordinated by six sulfonato oxygen atoms and one oxygen atom of water molecule where as compound 3 ( Triclinic, P 1 ¯ ) revealed the existence of discrete ions i.e. [Cu(phen) 3 ] 2 + cation, 2,6-naphthalenedisulfonate (2,6-nds) anion and eleven water molecules of crystallization. These water molecules in wide channels show intermolecular non-covalent interactions with disulfonate anion and [Cu(phen) 3 ] 2 + cationic layer, leading to crystal lattice stabilization. The d–d bands found in diffuse-reflectance electronic spectrum arise from 2 A 1g ( d x 2− y 2 ) > 2 A 2g (d z2 ) ≈ 2 B 1g ( d xy ) > 2 B 2g ( d xy ) ≈ 2 B 3g ( d yz ) transitions. A rare resolution of copper hyperfine splitting of powder EPR spectrum is observed only at low temperature. [ABSTRACT FROM AUTHOR]

Reaction of hydrated copper (II) 2-iodobenzoate with β/γ-picoline in methanol:water mixture (4:1, v/v) yielded two rare aqua bridged zig-zag polymers [Cu(2-iodobenzoate) 2 (β-picoline) 2 (μ-H 2 O)] n ; 1 and [Cu(2-iodobenzoate) 2 (γ-picoline) 2 (μ-H 2 O)] n ; 2 . The newly synthesized complexes have been characterized by elemental analysis, FT-IR spectroscopy, UV–Vis spectroscopy and single crystal X-ray structure determination. Complex 1 crystallized in monoclinic crystal system with C2/c space group, and complex 2 crystallized in triclinic crystal system with P 1 ‾ space group. X-ray structure determination revealed the presence of 1-dimensional chains of constituent molecules running along a -axis in both complexes. Water molecules act as bridges between constituent molecules and hence play a crucial role in 1-dimensional chain propagation in zig-zag manner. Empty channels have been observed between the zig-zag chains of complexes. Non-covalent interactions interactions such as O–H⋯O, C–H⋯O and C–H⋯π have been observed, which play a decisive role in the stabilization of crystal lattices in both complexes 1 and 2 . [ABSTRACT FROM AUTHOR]

A new tetranuclear thallium complex, [Tl 4 (H 2 O) 2 (anthracene-9-carboxylate) 4 ] was isolated by reaction of hot aqueous solution of thallium(1)sulphate with sodium salt of anthracene-9-carboxylic acid in water taken in appropriate stoichiometric ratio. The newly synthesized complex was characterized by elemental analysis, thermogravimetric analysis, spectroscopic studies (FT-IR, UV–Visible, and multinuclear NMR). Complex crystallizes in monoclinic crystal system with P2 1 /n space group. X-ray crystal structure determination revealed the presence of neutral centrosymmetric tetranuclear complex which contains two symmetry independent thallium cations. Tl1 is four-coordinate and bonded to three different anthracene-9-carboxylate anions. The other thallium cation, Tl2, is three-coordinate, being surrounded by two carboxylate oxygen atoms from two different ligands; anthracene-9-carboxylate and a water molecule. The crystal lattice is stabilized by C H/O H⋯O hydrogen bonding and cation⋯π interactions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis of new cationic species [Cu(temed)(H2O)4]2+. [•] Complex have been characterized by X-ray crystallography and spectroscopic techniques. [•] The crystal lattice is stabilized by the extensive hydrogen bonding (O H⋯O and C H⋯O). [Copyright &y& Elsevier]

Highlights: [•] Two rare aqua bridged copper(II) based linear polymers have been synthesized. [•] These polymers were structurally characterized by X-ray crystallography. [•] Empty channels have been observed between the linear chains of complexes. [•] Covalent interactions like O H⋯O, C H⋯O and C H⋯π has been observed. [Copyright &y& Elsevier]

In an endeavor to study how a polydentate nitrogen donor ligand affects the magnetic properties of copper(ii) methoxybenzoates, three novel complexes of copper(ii) were investigated. [Cu2(H2tea)2(o-methoxybenzoate)2], [Cu2(H2tea)2(m-methoxybenzoate)2]·2H2O and [Cu2(H2tea)2(p-methoxybenzoate)2]·2H2O (where H2tea = mono-deprotonated triethanolamine) were synthesized by addition of triethanolamine (H3tea) to the hydrated Cu(o-,m-,p-methoxybenzoates)2. The newly synthesized complexes have been characterized by elemental analyses, spectroscopic techniques (electronic and FT-IR), magnetic moment determination, molar conductance studies, TGA, and single crystal X-ray determination. The experimental characterization was integrated with the ab initio theoretical determination of the magnetic coupling constant value and with the analysis of the correlation between this value and the relevant geometrical parameters. Variable temperature solid state magnetization measurements and ab initio calculations indicate a remarkable ferromagnetic coupling of the unpaired electrons centered on the two Cu atoms for the m- and p-methoxybenzoate complexes (J = 100.9 cm−1), while a non-negligible antiferromagnetic coupling is found for the third complex (J = −83.1 cm−1). This differential behaviour can be rationalized on the basis of the out-of-plane displacement (τ) of the alkoxo group with respect to the molecular Cu2O2 plane. Large τ values prevent an efficient overlap between the O 2p and the magnetic Cu 3dx2−y2, favouring a ferromagnetic coupling between the Cu sites. [ABSTRACT FROM AUTHOR]

Three novel copper(ii) 2-nitrobenzoate complexes, [Cu(γ-pic)2(2-nitrobenzoate)2] 1, [Cu(β-pic)2(2-nitrobenzoate)2(H2O)2] 2 and [Cu2(H2tea)2(2-nitrobenzoate)2]·2(H2O) 3 (where γ-pic = 4-methylpyridine, β-pic = 3-methylpyridine and H2tea = mono deprotonated triethanolamine), were isolated by addition of γ-pic, β-pic and H3tea to the hydrated copper(ii) 2-nitrobenzoate, [Cu2(2-nitrobenzoate)4(H2O)2]·2H2O, suspended in a methanol : water (4 : 1) mixture. The newly synthesized complexes have been characterized by elemental analyses, thermogravimetric analysis (TGA), spectroscopic techniques (EPR, IR and UV/Visible), magnetic susceptibility measurements, single crystal X-ray structure determination and DFT study. All compounds crystallize in the monoclinic crystal system with the P21/c space group. X-ray structure determination revealed the presence of monomers in both 1 and 2 and dimer in 3 with the deprotonated oxygen atom of the H2tea ligand bridging two Cu(ii) atoms. Two co-crystallized water molecules are also present in 3. The crystal lattice is stabilized by C–H…O hydrogen bonding interactions in 1 and O–H…O, C–H…O hydrogen bonding interactions in 2 and 3. The dimeric complex exhibits relatively strong ferromagnetic exchange with J = −100 cm−1 (corresponding to H = JS1S2). The zero-field splitting parameters (zfs) of the dimer triplet states D and E were derived from HF EPR spectra recorded at moderately low temperatures. The sign of D was determined from low-temperature HF EPR spectra. [ABSTRACT FROM AUTHOR]

Two mononuclear copper(II) complexes of composition [trans-Cu(en)2(H2O)2](p-methoxy cinnamate)2, 1 and [trans-Cu(en)2(H2O)2](p-nitrocinnamate)2·2H2O, 2 (where en=ethylenediamine) were synthesized by the addition of strong chelating base ethylenediamine to hydrated Cu(II) cinnamates, Cu(p-methoxy/p-nitrocinnamate)2·xH2O in methanol–water mixture. The newly synthesized complexes have been characterized by physicochemical, spectroscopic techniques and X-ray crystallography. The complex 1 crystallizes in the monoclinic crystal system with space group, P21/c and complex 2 crystallizes in the monoclinic crystal system with space group, C2/c. X-ray structure determination revealed ionic structures consisting of one complex cation [trans-Cu(en)2(H2O)2]2+, two p-methoxycinnamate anions in complex 1 while complex 2 consists of one complex cation [trans-Cu(en)2(H2O)2]2+, two p-nitrocinnamate anions and two water molecules of crystallization. The interactions of these complexes with bovine serum albumin (BSA) were investigated using fluorescence spectroscopy. The result of fluorescence titration revealed that the complexes can quench the intrinsic fluorescence of BSA through both static and collisional (dynamic) quenching mechanism. Quenching constant, association binding constant and number of binding sites were calculated by using modified Stern–Volmer and Scatchard equation. Both complexes display good binding propensity to bovine serum albumin protein with 4.07×105 and 1.88×105 M−1 binding constant value for complexes 1 and 2 respectively, indicating strongest protein-binding ability in complex 1 as compared to 2. [ABSTRACT FROM AUTHOR]

Abstract: The research on biomedical applications of nanoparticles has seen an upsurge in recent years due to their unique capabilities in treatment of ailments. The present paper reports the synthesis of Au–Fe3O4 hybrid nanoparticles. The formation of these nanoparticles was confirmed by transmission electron microscopy (TEM) and physical property measurement system (PPMS). Next step of this paper reveals potential use of novel hybrid of chitosan-g-glycolic acid and Au–Fe3O4 hybrid nanoparticles in controlled drug delivery and tissue engineering applications. Grafting of glycolic acid and drug loading in porous scaffold was characterized by Fourier transform infrared spectroscopy. The nanohybrid scaffolds were found to be stable regardless of pH of the medium and play a key role in cell adhesion, proliferation and migration. Au–Fe3O4 hybrid nanoparticles reinforcement was found to control the drug (cyclophosphamide) release rate in phosphate buffer saline solution (pH 7.4). Therefore, Au–Fe3O4 hybrid nanoparticles are viable additive for formulating sustained drug delivery systems based on glycolic acid grafted chitosan. The cell proliferation profile also shows that prepared nanohybrid is biocompatible providing suitable substrates for tissue engineering. [Copyright &y& Elsevier]

Abstract: In an effort to study the binding of substituted arylsulphonates by cationic cobalt(III) complex [Co(phen)2CO3]+, two complex salts [Co(phen)2CO3](4-chlorobenzenesulphonate)⋅3H2O, 1 and [Co(phen)2CO3] (2,4-dinitrobenzenesulphonate)⋅H2O, 2 have been synthesized. These complex salts were characterized by elemental analysis, solubility product, conductivity measurements, thermal and spectroscopic studies. The crystal structures of 1 and 2 have been determined by single-crystal X-ray structure determination. Both complex salts crystallize in triclinic system (space group ) with cell dimensions a =10.215(5)Ǻ, b =12.013(5)Ǻ, c =12.822(5)Ǻ, α =69.497(5), β =88.855(5), γ =78.430(5)°, Z =2, V =1441.6(11)Ǻ3 for 1 and a =7.730(5)Ǻ, b =13.958(5)Ǻ, c =14.020(5)Ǻ, α =73.763(5), β =88.352(5), γ =81.035(5)°, Z =2, V =1434.5(11)Ǻ3 for 2. The hydrogen bonding (CO and OO) and π–π stacking interactions result in the formation of bi-layered and zig–zag structures in 1 and 2 respectively. The facile formation of complex salts with small K sp values and detailed packing analysis suggests that the [Co(phen)2CO3]+ complex ion may be effective as a binding agent for substituted arylsulphonates in an aqueous medium. [Copyright &y& Elsevier]

Abstract: Cobalt(III) complexes containing carboxylate anions, [Co(phen)2CO3]X·nH2O, where X=trifluoroacetate ( tfa , n =5; 1), 4-chloro-3-nitrobenzoate ( 3-cnbz , n =6; 2), 4-chloro-2-nitrobenzoate ( 2-cnbz , n =4; 3), 2,4-dinitrobenzoate ( dnbz , n =1; 4), have been synthesized by the reaction of [Co(phen)2CO3]Cl·5H2O and corresponding sodium salt of carboxylic acid in aqueous medium. These complexes were characterized by elemental analysis, solubility product, conductance measurements, thermal studies and spectroscopic studies. The crystal structures of 1–4 have been determined by single-crystal X-ray structure determination. The hydrogen bonding (C–H⋯O and O–H⋯O) and π–π stacking interactions led to the formation of pillared layer, square cavities type and zig-zag layered arrangements in 2, 3 and 4 respectively, while in complex salt 1, C–H⋯F interactions have been observed between the complex cations and anions. [Copyright &y& Elsevier]

Abstract: This work presents the potential use of novel nanohybrid based on chitosan-g-glycolic acid and Pt–Fe3O4 composite nanoparticles in drug delivery and tissue engineering applications. The Pt–Fe3O4 hybrid nanoparticles are prepared by thermal decomposition of H2PtCl6·6H2O at high temperature. The prepared nanoparticles were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and physical property measurement system (PPMS). Next step of this paper reveals the potential use of novel hybrids of chitosan-g-glycolic acid and Pt–Fe3O4 hybrid nanoparticles in controlled drug delivery applications. The drug loaded nanohybrid scaffold is prepared by freeze drying of grafted polymer solution. Drug loading and grafting of chitosan was characterized by Fourier transform infrared spectroscopy (FTIR). The cell proliferation also shows that the prepared nanohybrids are biocompatible. The nanohybrid was found to be stable regardless of pH of the medium. Therefore, Pt–Fe3O4 hybrid nanoparticles are viable additive for sustained drug delivery and it could be applied in the field of biomedical. [Copyright &y& Elsevier]

Abstract: In the present study, four new Co(II/III) metal complexes, [Co(phen)3]S4O6·2H2O (1), [Co(phen)3]S4O6·7H2O (2), [Co(phen)3]2(S4O6)3·6.5H2O (3) and [Co(phen)3]S2O3·9H2O (4), have been synthesized and characterized by elemental analysis, TGA and various spectroscopic techniques. In the case of 1 and 2, an unexpected redox reaction took place and the complexes formed are different in terms of their water of crystallization. The structures of 1–3 have been determined by single crystal X-ray crystallography. Complex salts 1–3 crystallize in the orthorhombic (Pbca), triclinic () and monoclinic (P21/c) crystal systems, respectively. Their X-ray crystal structure determination revealed the presence of non-covalent cation-to-anion (C–H⋯Oanion hydrogen bonds), anion-to-cation (anion⋯π interactions) and cation-to-cation (C–H⋯π and π⋯π stacking interactions) interactions. Interestingly, a detailed packing analysis has shown the presence of rare chains of cyclic water hexamers (chair form) and tetramers, stabilized by O–H⋯O and C–H⋯O hydrogen bond interactions in the supramolecular complex [Co(phen)3]S4O6·7H2O (2). [Copyright &y& Elsevier]

Abstract: Rare monomeric as well as dimeric Cu(II) complexes, [Cu2(β-pic)4L4][Cu(β-pic)2L2(H2O)2]·2H2O (1), (where L=cinnamate and β-pic=β-picoline) in one single crystal have been synthesized by the reaction of copper(II) cinnamate and excess of β-pic while a monomeric complex [Cu(py)2L2(H2O)]·py (2) was obtained in a similar reaction by using py (py=pyridine) instead of β-pic. Both of these copper(II) complexes have been characterized by spectroscopic techniques, TGA, X-ray crystallography and DFT studies. [Copyright &y& Elsevier]

Abstract: Two new copper(II) complexes comprising of coordinated and non-coordinated p-toluenesulfonate, [trans-Cu(γ-pic)2(H2O)4](pts)2·2H2O, 1 and [trans-Cu(γ-pic)4(pts)2]·2H2O, 2 (where p-toluenesulfonate=pts and γ-picoline=γ-pic) have been isolated from the same reaction mixture. These complexes have been characterized by spectroscopic techniques, molar conductance, TGA, magnetic susceptibility studies, and single crystal X-ray structure determination. Both complexes crystallize in the monoclinic crystal system with P21/c space group having cell dimensions of a =8.0203(2)Å, b =19.4471(4)Å, c =10.3000(3)Å, β =93.4420(9)°, V =1603.61(7)Å3, (Z =2) in 1 and a =10.1473(2)Å, b =10.9948(2)Å, c =18.0952(5)Å, β =93.0340(9)°, V =2015.96(8)Å3, (Z =2) in 2. Single -crystal X-ray structure determinations revealed the presence of ionic complex, viz: one complex cation [trans-Cu(γ-pic)2(H2O)4], two pts anions and two water molecules of crystallization in the complex 1 and neutral [trans-Cu(γ-pic)4(pts)2] and two water molecules of crystallization in 2. The crystal packing in both complexes is stabilized by OO, CO hydrogen bonds and Cπ interactions. [Copyright &y& Elsevier]

Abstract: This paper reports a simple novel method for the synthesis of flower like gold nanoparticle (three dimensional branched nanoparticle) with >30 tips, under controlled temperature condition. Formation of flower like Au nanoparticle was confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Next step of this paper reveals the potential use of novel hybrids of chitosan-g-glycolic acid and gold nanoflower (AuNF) in controlled drug delivery and tissue engineering applications. The drug loaded novel nanohybrid scaffold is prepared by freeze drying of grafted polymer solution. Grafting of glycolic acid to the chitosan and incorporation of drug were evaluated by Fourier transform infrared spectroscopy (FTIR). The nanohybrid scaffolds were found to be stable towards the pH of the medium. The cell viability study shows that prepared nanohybrid scaffolds are biocompatible. Gold nanoflowers were found to control the drug release rate in the buffer solution (pH 7.4). Therefore, for the glycolic acid grafted chitosan based system, gold nanoflowers are the viable additive for drug delivery. [Copyright &y& Elsevier]

Abstract: A new anion [CdBr4(C7H5O2)]3−, where C7H5O2 = benzoate, has been isolated for the first time in the form of complex salt [Co(en)3] [CdBr4(C7H5O2)]·H2O(1). This is the first example where Cd(II) centre is coordinated by both inorganic and organic ligands and existing as discrete unit. The complex salt is characterized by spectroscopic techniques and single crystal X-ray crystallography. The formation of complex salt is also supported by DFT calculations. [Copyright &y& Elsevier]

Abstract: Two new cobalt(III) complex salts, [Co(en)3]2[CdBr6]·Br2·2H2O (1) and [Co(en)3]2[trans-CdBr4Cl2]·Br2·2H2O (2) have been synthesized while attempting to synthesize [CdBr5]3− complex ion. The newly synthesized complex salts have been characterized by elemental analyses, spectroscopic techniques (e.g. UV/Visible, IR and NMR), solubility product, conductance measurements and luminescent studies. Both the complex salts 1 and 2 crystallize in monoclinic crystal system with space group P2 1/c. Single crystal X-ray structure determination revealed the presence of ionic structures and discrete anions [CdBr6]4− and [trans-CdBr4Cl2]4− in 1 and 2, respectively. This is the first report of synthesis and single crystal X-ray structure determination of discrete and mixed halogenocadmate(II) anion, [trans-CdBr4Cl2]4−. The crystal lattices of both complex salts are stabilized by N–H⋯Br/Cl, C–H⋯Br/Cl and O–H⋯Br hydrogen bonds besides electrostatic forces of attraction. [Copyright &y& Elsevier]

Abstract: A novel mixed ligand cobalt(III) complex, [Co(phen)2(Hbiim)]Cl2·10H2O, has been utilized in the syntheses of three halogenocadmate(II) complexes [Co(phen)2(Hbiim)][CdCl4]·2H2O (1), [Co(phen)2(Hbiim)][CdBr4]·1.5H2O (2) and [Co(phen)2Hbiim][CdI4]·C3H6O·0.5H2O (3) (where phen=1,10-phenanthroline and Hbiim=mono-anionic 2,2′-biimidazole). The complex salts 1–3 have been characterized by elemental analyses, spectroscopic techniques (UV–Vis, FT-IR and NMR) solubility product and conductivity measurements. Thermal behaviors and single crystal X-ray structure determination of the complex salts 1–3 are also discussed. The complex salts 1 and 2 are isomorphous and crystallize in space group , while 3 crystallizes in the monoclinic crystal system with the space group Pc. The two crystallographically different complex cations in 3 correspond to Λ and Δ optical isomers. The crystals of 1 and 2 are centrosymmetric and so both isomers cohabit in the solid state as a racemate. The spatial disposition of the cations in the three complex salts, derived from the existence of the optical isomers, favours the formation of hydrogen bonding, as revealed by the presence of a (10) ring motif. The packing analyses of complex salts 1 and 2 shows the presence of open channels in which solvent molecules of crystallization are residing, while in 3 an ABCABC…type layered packing arrangement of constituents has been observed. Non-covalent interactions like C–H···X(Cl/Br/I), C–H···O (second sphere interactions) and O–H···O (water) play a key role in the stabilization of the crystal lattices. [Copyright &y& Elsevier]