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Multi-class motor imagery Electroencephalography (EEG) activity decoding has always been challenging for the development of Brain Computer Interface (BCI) system. Deep learning has recently emerged as a powerful approach for BCI system development using EEG activity. However, the EEG activity analysis and classification should be robust, automated and accurate. Currently, available BCI systems perform well for binary task identification whereas, multi-class classification of EEG activity for BCI applications is still a challenging task. In this work, a hybrid residual attention ensemble voting classifier model is developed for EEG-based Motor Imagery-Brain Computer Interface (MI-BCI) task classification. The Time–Frequency Representation (TFR) of the multi-class EEG activity is generated using Transient Extracting Transform. The TFR spectrogram images are input to the designed residual attention ensemble voting classifier model for training and classification purposes. The model is evaluated using different fusion strategies viz. feature-level and score-level fusion of layers. The proposed model is evaluated on two MI-BCI datasets, BCI competition IV 2a and BCI competition III 3a, yielding the highest classification accuracies of 88.14% and 93.13%, respectively. The results obtained on a large multi-class MI-BCI dataset confirm that the proposed hybrid residual attention ensemble voting classifier model significantly outperforms the conventional algorithm and achieves significantly high classification accuracy for the feature-level fusion of layers. The developed framework aids in identifying different tasks for multi-class MI-BCI EEG activity. [ABSTRACT FROM AUTHOR]

A primary goal of the present work is to study the physicochemical properties of magnetic nanoparticles (magnetite) coated with identical primary surfactants but have different secondary surfactants. The properties studied are magnetic, rheological and magnetoviscous under different shear rates and magnetic fields. The bilayer surfactant thickness was determined using dynamic light scattering and magnetization measurements. Magnetoviscous data revealed that the magnetic field-induced change in viscosity was dominated by oversize particles only and that there was no pre-agglomerate present in the fluids. These results were compared to Rosensweig et al. prior model for viscosity change as well as with Shiliomis's theory of viscous behavior of dilute suspension of noninteracting particles. The presence of a secondary surfactant on the magnetic surface affects the carrier-surfactant interaction and the stability of the colloid. Two-surfactant system increases the chain length and reduces and weakens the dipolar interactions. Thus, in such a ferrofluid a minimum particle agglomeration can be expected. This work shows that it does not matter whether the fluid is manufactured with one surfactant/one carrier or two surfactants/two carriers; the fluid's stability is the most important parameter. [ABSTRACT FROM AUTHOR]

Dielectric breakdown of transformer oil (T-oil) and T-oil based magnetic fluid containing Mn–Zn ferrite nanoparticles is investigated in the absence and presence of magnetic fields. The influence of the time of exposure to the magnetic field on the breakdown voltage of the magnetic fluid Mn–Zn is reported for the first time. Visual evidence of bubble formation due to elevated electrical stress on the T-oil is captured to understand the BDV mechanism in the T-oil. The displacement of bubbles in relation to time is studied. This confirms the formation of bubbles and the propagation of the streamer as the mechanism responsible for the dielectric breakdown in T-oil. The T-oil based magnetic fluid containing Mn–Zn ferrite nanoparticles (1.003 vol.%) showed a 40% increase in the BDV value in comparison with pure T-oil. The increase in BDV of magnetic fluid is explained using the concept of nanoparticles acting as electron scavengers and modifying the breakdown process significantly as compared to that of T-oil. A rise in BDV over exposure time is observed at a given magnetic field. The maximum BDV enhancement in the presence of a magnetic field (20.1 mT and 20 min exposure time) is 78% when compared to pure T-oil. Improving BDV by adding magnetic nanoparticles can allow this oil to be used in higher power transformers. [ABSTRACT FROM AUTHOR]

The present study focuses on the neotectonics activity and related mass movement along the Eastern Ramganga River Basin (ERRB), Kumaun Himalaya, India. To understand the contemporaneous landform development, the quantitative analysis of drainage network is combined with field-based geomorphic attributes and recent seismicity data. The Ramganga River traverses across major thrusts, e.g., Main Central Thrust (MCT), Munsiari Thrust (MT) and Berinag Thrust (BT), and subsidiary faults, e.g., Namik Fault, Kaphli Fault, Hokara Fault, Kaphlikot-Ramari Fault and Ramganga Fault. Furthermore, the NNW–SSE trending faults (e.g., Naulara-Chilkiya Fault (NCF) and Nankana-Kapisar Fault (NKF) were also demarcated by means of characteristic geomorphic features in the upper catchment of the basin. The observed geomorphic elements such as uplifted fluvial terraces, several small to large waterfalls, fault facets, active and stabilized landslides, deflected and migrated streams, wide/straight river course converting into narrow passage, entrenched river channels, palaeo-channels and dissected hills etc. demonstrate symptomatic footprints of landscape evolution within the basin and also reveal that the thrusts/faults traversing through the ERRB are reasonably active. The field investigations are further verified by measuring various morphometric indices, results of which indicate elongated and asymmetric valleys, highly dissected drainage basin, high relief, sharp deflections in streams, slope breaks with remarkable values of stream length gradient index (SL) and steepness index (Ks). Further, we observed anomalous geomorphic expressions with possible surface deformation within thrust/fault zones as well as along anticlinal axis in the upper catchment which is characterized by higher slope, relief, accelerated erosion, incision, uplift and mass movements. Such features in the thrust/fault-fold belt of the region and recurrent seismicity appear responsible for triggering severe landslides under intense rainfall. The outsized disastrous landslides have resulted in destruction of human settlement, disconnecting road networks, damage of property and loss of lives particularly during the monsoon period. Therefore, we recommend that proper geological and geo-technical surveys are of utmost importance to identify susceptible sites all along the basin length. [ABSTRACT FROM AUTHOR]

Three different design parameters of magnetic fluid seal are optimized for the maximum pressure differential capacity of the seal. The program finite element method magnetics (FEMM) based on finite element method is used to find the magnetic flux inside the gap for all the combinations of the design parameters. The data are analyzed using the MINITAB statistical analysis software. The multivariable regression analysis technique is used to find the percentage effect of different parameters and also the optimized dimensions. The effect of magnetic fluid volume on maximum pressure differential capacity of a seal is observed, and the optimized volume is found. The results provide enough data to design and fabricate the seal. This seal can be used in positive as well as negative pressure applications. For example, as vacuum rotary shaft seal in low-pressure chemical vapor deposition machines, pressure seal for stirrer shaft in chemical process chambers to seal toxic gases. This seal can also be used as an exclusion seal, such as a bearing protection seals in robotic arms used in manufacturing plants. [ABSTRACT FROM AUTHOR]

Synthesis of pure and Yb3+, Er3+ and Er3+/Yb3+ doped La3Ga5.5Nb0.5O14 (LGN) ceramics by solid state reaction method and their photoluminescence characteristics are presented. Er3+ and Er3+/Yb3+doped LGN ceramics emit green light at 523 (2H11/2 → 4I15/2) and 551 (4S3/2 → 4I15/2) nm through down conversion upon UV excitation. Er3+/Yb3+-doped LGN ceramics also act as upconvertors, by transforming infrared excitation (973 nm) into UV light (4G11/2 → 4I15/2) which is due to three-photo energy transfer process. The emission characteristics confirm that LGN is a superior host material for both up and down conversions and hence it can be used for light emitting devices and biological applications. The effects of Er3+ and Yb3+ doping on the structure, morphology of the prepared ceramics were also studied and discussed. [ABSTRACT FROM AUTHOR]

This paper reports the study of structural, morphological and dielectric properties of pure and Al substituted Langasite (LaGaAl SiO, x = 0, 0.2, 0.4, 0.6 and 0.8) ceramics, prepared at 1400 °C by solid state reaction method. Phase purity, structure and crystallinity of all the samples were investigated by powder X-ray diffraction study which confirmed the Langasite (LGS) type structure for the synthesized samples. Al substituted ceramics exhibited low dielectric constant than the pure LGS. The ac conductivity values decrease with increase in Al-concentration, but increase with temperature and frequency. The result of Nyquist plot shows the presence of bulk resistive grain contributions and also confirms the increase of resistance with Al content in LGS. Our results may assist a way for the easy fabrication of Langasite based devices with improved resistivity properties by substituting a small amount of Al. [ABSTRACT FROM AUTHOR]

Plant defense against their pathogens can be induced by a complex network of different inducers. The present study investigates the synergistic effect of Trichoderma harzianum, exogenous salicylic acid (SA) and methyl jasmonate (MeJA) over the response and regulation of the antioxidant defense mechanisms and lipid peroxidation in tomato plants against Fusarium wilt disease. In the present work, tomato plants were infected by Fusarium oxysporum f. sp. lycopersici 3 days after inoculated with T. harzianum and/or sprayed daily for 3 days with chemical inducers (SA and MeJA). Plants were analysed at 0, 24, 48, 72 and 96 h after inoculation with Fusarium oxysporum f. sp. lycopersici. Infection of tomato plants by pathogen led to strong reduction in the dry weight of roots and shoots with the enhanced concentration of HO and varying degree of lipid peroxidation. Concurrently, exogenous SA, when applied with pathogen greatly enhanced HO content as well as activities of antioxidant enzymes except catalase (CAT) and ascorbate peroxidase (APx). The pathogen challenged plants pretreated with T. harzianum and MeJA together exhibited less lipid peroxidation and as well as the elevated level of ascorbic acid and enhanced activities of antioxidant enzymes. All applied treatments protected tomato seedlings against Fusarium wilt disease but the percentage of protection was found higher in plants pretreated with the combination of T. harzianum and chemical inducers. [ABSTRACT FROM AUTHOR]

In vitro environments like heat stress usually increase the production of reactive oxygen species in bubaline oocytes which have been implicated as one of the major causes for reduced developmental competence. Oocytes during meiotic maturation are sensitive to oxidative stress, and heat stress accelerates cellular metabolism, resulting in the higher production of free radicals. Therefore, the aim of present work was to assess the impact of heat stress during meiotic maturation on bubaline cumulus-oocyte complexes (COC), denuded oocytes (DO), and cumulus cell mass in terms of their oxidative status. Accordingly, for control group, COC were matured at 38.5 °C for complete 24 h of meiotic maturation and heat stress of 40.5 and 41.5 °C was applied to COC during the first 12 h of maturation and then moved to 38.5 °C for rest of the 12 h. In another group, COC after maturation were denuded from the surrounding cumulus cells by manual pipetting. Results indicated that the production of reactive oxygen species (ROS), lipid peroxides, and nitric oxide (NO) was significantly ( P < 0.05) higher in the oocytes subjected to heat stress (40.5 and 41.5 °C) during meiotic maturation compared to the oocytes matured under standard in vitro culture conditions (38.5 °C). Also, the antioxidant enzymatic activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase were significantly ( P < 0.05) increased in all the treatment groups compared to the control group. Therefore, the present study clearly establishes that heat stress ensues oxidative stress in bubaline oocytes which triggers the induction of antioxidant enzymatic defense system for scavenging the ROS. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the genome integrity so as to assess the adaptability of three breeds of indigenous cattle reared under arid and semi-arid regions of Rajasthan (Bikaner) and Haryana (Karnal) India. The cattle were of homogenous group (same age and sex) of indigenous breeds viz. Sahiwal, Tharparkar and Kankrej. A total of 100 animals were selected for this study from both climatic conditions. The sister chromatid exchanges (SCE's), chromosomal gaps and chromatid breaks were observed in metaphase plates of chromosome preparations obtained from in vitro culture of peripheral blood lymphocytes. The mean number of breaks and gaps in Sahiwal and Tharparkar of semi-arid zone were 8.56 ± 3.16, 6.4 ± 3.39 and 8.72 ± 2.04, 3.52 ± 6.29, respectively. Similarly, the mean number of breaks and gaps in Tharparkar and Kankrej cattle of arid zone were 5.26 ± 1.76, 2.74 ± 1.76 and 5.24 ± 1.84, 2.5 ± 1.26, respectively. The frequency of SCEs in chromosomes was found significantly higher ( P < 0.05) in Tharparkar of semi-arid region (4.72 ± 1.55) compared to arid region (2.83 ± 1.01). Similarly, the frequency of SCEs was found to be 4.0 ± 1.41 in the Sahiwal of semi-arid region and 2.69 ± 1.12 in Kankrej of arid zone. Statistical analysis revealed significant differences ( P < 0.05) amongst the different zones, i.e. arid and semi-arid, whereas no significant difference ( P > 0.05) was observed in the same zone. The analysis of frequency of CAs and SCEs revealed significant effects of environmental conditions on the genome integrity of animals, thereby indicating an association with their adaptability. [ABSTRACT FROM AUTHOR]

This study highlighted the social vulnerability to climate change of 29 eastern coastal districts across 4 eastern coastal states of India by using the 'Integrated vulnerability assessment approach' and IPCC's definition of vulnerability. The assessment was based on secondary data, like socio-economic and bio-physical indicators, collected from several authenticated sources; and weightage of these indicators were assigned by using Principal Component Analysis. Vulnerability was calculated as the net affect of exposure and sensitivity on the adaptive capacity. Pudukottai district of Tamil Nadu was found to be the most vulnerable district, while East Godavari district of Andhra Pradesh was the least vulnerable. The net effect was found to be negative in 10 districts: South 24-Parganas of West Bengal; Bhadrak of Odisha; Prakasam of Andhra Pradesh; Thiruvallur, Villipuram, Thanjavur, Thoothukkudi, Pudukottai, Ramanathapuram and Cuddalore of Tamil Nadu. This net negative effect may be considered as an indicator of alarming situation. [ABSTRACT FROM AUTHOR]

Magnetic, nano-crystalline samples of zinc substituted nickel ferrite, (ZnNiFeO for x = 0.0-0.9 in step of 0.2), are synthesized using microwave combustion synthesis technique. The structural properties of Ni-Zn are determined using X-ray powder diffraction, transmission electron microscopy; Fourier transforms infrared spectroscopy and neutron diffraction techniques. Average crystalline size obtained from X-ray diffraction and neutron diffraction is in the range of 30-60 nm. The cation distribution obtained from X-ray diffraction and neutron diffraction show that Zn occupies only tetrahedral A-site in the spinel lattice. The values of magnetic moment derived from magnetization measurements and neutron diffraction agrees nearly 97 % to that of bulk at 300 K. This methodology can be used to prepare large quantities (about 10 g) of sample at one time using kitchen microwave oven working at 1,200 W power. [ABSTRACT FROM AUTHOR]

Objective: To determine the direct effect of physiologically relevant high temperatures (40.5 and 41.5 °C) for two time periods (12 and 24 h) on bubaline oocytes during in vitro maturation. Method: The control group oocytes were cultured at 38.5 °C for 24 h. The treatment 1 (T1) and 3 (T3) group oocytes were cultured at 40.5 and 41.5 °C respectively, for the first 12 h and at 38.5 °C for rest of the 12 h. However, treatment 2 (T2) and 4 (T4) group oocytes were cultured at 40.5 and 41.5 °C for complete 24 h. Results: Development of oocytes to blastocyst was severely compromised ( p < 0.001) when matured at 40.5 and 41.5 °C for both exposure periods (12 h and 24 h). It was found that the cleavage rates, blastocyst yield and mean cell number decreased remarkably ( p < 0.001) in the treatment groups compared to control. The relative mRNA expression of heat shock protein ( Hsp 70.1, 70.2, 70.8, 60, 10 and HSF1), pro-apoptotic ( caspases- 3, −7, −8, Bid and Bax) and oxidative stress ( iNOS) related genes was significantly higher ( p < 0.05) in all the treatment groups compared to control. However, mRNA abundance of anti-apoptotic ( Bcl- 2, Mcl- 1, Bcl- xl), glucose transport ( Glut1, Glut3 and IGF1R), developmental competence ( ZAR1 and BMP15) and oxidative stress ( MnSOD) related genes was significantly decreased ( p < 0.05) in the treatment groups compared to control. Conclusion: The present study clearly establishes that physiologically relevant elevated temperatures during in vitro meiotic maturation reduce developmental competence of bubaline oocytes. [ABSTRACT FROM AUTHOR]

A comparison between two different types of thermal radiation sources maintaining near blackbody conditions has been carried out in the range from 50 to 500 °C. An infrared total radiation pyrometer was used as a transfer standard to measure the temperature of blackbodies. A thorough study of temperature distribution has been carried out for the large surface source in order to characterize the best location over the surface blackbody for temperature determination precisely of the order of better than 0.1 °C. The expanded uncertainty in the estimation of temperature of the radiating source in the above range of measurement was evaluated to be within ±0.24 °C at 50 °C and ±0.88 °C at 500 °C. The blackbody temperature sources found to be suitable for calibration of infrared total radiation pyrometers and thermal imaging devices in the operational range as mentioned above for laboratory use or other industrial and medical applications. [ABSTRACT FROM AUTHOR]

Extracellular ligninolytic enzyme activities were determined in two white-rot fungi, Bjerkandera adusta and Lentinus squarrosulus. To investigate the activity of extracellular enzymes, cultures were incubated over a period of 20 days in nutrient rich medium (NRM) and nutrient poor medium under static and shaking conditions. Enzymatic activity was varied with media and their incubation conditions. The highest level of Aryl alcohol oxidase (AAO) was detected under shaking condition of both medium while Manganese peroxidase (MnP) activity was best in NRM under both conditions. AAO is the main oxidases enzyme in B. adusta while laccase plays important role in L. squarrosulus. MnP is the main peroxidase enzyme in both varieties. [ABSTRACT FROM AUTHOR]

Craterellus indicus is proposed here as a new species, resulting from a morphological and molecular study on the diversity of Cantharellaceae in the western Himalayan region of India. The species is characterized by a pale brownish to creamish pileus and a smooth to folded hymenium that is distinctly detached from the stipe apex. There are no clamp connections. The combination of characters makes this species distinct from other known species of Craterellus. Molecular phylogenetic analysis of partial large subunit (LSU) and the ITS region of the nuclear ribosomal operon supports its position as a new species. [ABSTRACT FROM AUTHOR]

Objective: To identify the determinants of neonatal mortality. Study design: Nested case-control study. Study setting: 28 villages under the intensive field practice area of Comprehensive Rural Health Services Project, Ballabgarh, Haryana serving a population of 87,016, as on 31st December 2009. The study period was from 2005 to 2009. Methods: The data were obtained from Health Management Information System and analyzed using multivariate logistic regression analysis. A hierarchical approach was used to analyze the factors associated with neonatal deaths, using community level factors, socio-economic status and biological determinants. The population attributable fractions were estimated for significant variables. Results: The total live births during the study period were 10392 and neonatal deaths were 248. The infant and neonatal mortality rates during the study period were 45.6 and 23.8 per 1000 live births, respectively. Socio-economic determinants (Low educational status of parents [OR 2.1, 95% CI; 1.4, 3.3]; father's occupation [OR 1.8, 95% CI; 1.0, 3.0]; Rajput caste [OR 2.0, 95% CI; 1.2, 3.4] appeared to explain a major fraction (45.7%) of neonatal deaths. Community level factors (villages with no health facility [OR 1.5, 95% CI; 1.0, 2.1]; villages with population >6000 [OR 1.7, 95% CI; 1.2, 2.5]) were associated with 27.3% of all neonatal deaths. Proximate determinants (early childbearing age of mother (<20 years) [OR 2.0, 95% CI; 1.2, 3.2]) were least important. All the three level of variables seemed to act independently with little mediation among them. Conclusion: Neonatal mortality is affected by socioeconomic, community level and proximate biological determinants. [ABSTRACT FROM AUTHOR]

Zero field cooled dc-magnetization measurements of monodispersed MnZnFeO nanoparticles dispersed in kerosene exhibit two transitions at low temperatures. These transitions correspond to (i) the superparamagnetic to blocked superparamagnetic and (ii) the blocked superparamagnetic to surface spin-glass like/quantum superparamagnetic state upon lowering the temperature. The existence of a disorder surface is confirmed by recording small-angle neutron scattering data below and above the Curie temperature. Magnetic relaxation analysis shows a plateau at low temperature (below 5 K) with a slight minimum at 3 K, which is a characteristic of the surface spin-glass-like state. This is analyzed considering the energy distribution n( E)∼1/ E. The existence of surface disorder dominates at low temperature and mimics the transition from superparamagnetic to quantum superparamagnetic states. [ABSTRACT FROM AUTHOR]

Core-shell nanostructures have emerged as an important class of functional materials with potential applications in diverse fields, especially in health sciences. In this article, nanoengineering of novel magnetic colloidal dispersion containing surface modifiable silica with a core of single domain magnetite nanoparticles loaded with photosensitizer (PS) drug 'Methylene blue' (MB) has been described. Magnetite core is produced by the well-established chemical coprecipitation technique and silica shell is formed over it by the modified hydrolysis and condensation of TEOS (tetraethyl orthosilicate). Conditions for reaction kinetics have been established to tailor the core-shell structures in the form of nanospheres and nanocapsules. MB is loaded into the nanostructures by demethylation reaction. The major conclusion drawn from this study is that the synthesis route yields stable, non-aggregated MB loaded superparamagnetic magnetite-silica nanostructures with tailored morphology, tunable loading, and excellent magnetic properties. [ABSTRACT FROM AUTHOR]

Microwave combustion technique modified by post treatment procedure is used to synthesize single-phase spinel ferrites of cobalt, zinc, and substituted magnetic nanoparticles of typical size 390 Å. The post treatment does not alter the crystal structure but increases the crystallinity. This is confirmed by powder x-ray diffraction and Fourier Transform Infrared (FTIR) studies. Citric acid is used as a fuel. The fresh synthesized sample shows an impurity phase in x-ray and in FTIR. This is due to the unreacted citrate molecule adsorbed on the particle surface. It is shown that by treating the sample with 0.1 M HCl, we can eliminate the impurity phase, and one can obtain a pure single phase. The magnetization at 8 kOe increases by nearly 8% after the removal of impurity. In order to remove surface adsorbed OH ion, samples are treated with NaCl and heated to 200°C for four hours. The XRD result indicates that after the treatment neither the crystallite size nor the distribution changes, but it removes OH ion. This is also confirmed by FTIR analysis. Thus, this modified technique can be used to synthesize pure nanocrystalline samples of spinel ferrites. [ABSTRACT FROM AUTHOR]

The eastern limb of horse shoe shaped 'Bonai Synclinorium' in India hosts Banded Iron Formations (BIFs), consisting of major high grade iron deposits. Phosphorus (P) gets adsorbed in the iron ore by way of ion exchange mechanism of clay minerals and hydrated secondary iron oxide minerals. Its concentration is lesser in hard ores and blue dust types of ores, while the highest in case of lateritic ores. P content reduces with increase in iron (Fe) content in individual ore types. Along the eastern limb, phosphorus content gradually reduces from north to south direction. Since phosphorus is mainly associated with secondary lateritization process, its concentration is very high in top weathered profile and along the weaker zones. [ABSTRACT FROM AUTHOR]

The use of nanoparticles as drug delivery systems for anticancer therapeutics has great potential to revolutionize the future of cancer therapy. The aim of this study is to construct a novel drug delivery platform comprising a magnetic core and biodegradable thermoresponsive shell of tri-block-copolymer. Oleic acid-coated FeO nanoparticles and hydrophilic anticancer drug 'doxorubicin' are encapsulated with PEO-PLGA-PEO (polyethylene oxide-poly d, l lactide-co-glycolide-polyethylene oxide) tri-block-copolymer. Structural, magnetic, and physical properties of FeO core are determined by X-ray diffraction, vibrating sample magnetometer, and transmission electron microscopy techniques, respectively. The hydrodynamic size of composite nanoparticles is determined by dynamic light scattering and is found to be ~36.4 nm at 25 °C. The functionalization of magnetic core with various polymeric chain molecules and their weight proportions are determined by Fourier transform infrared spectroscopy and thermogravimetric analysis, respectively. Encapsulation of doxorubicin into the polymeric magnetic nanoparticles, its loading efficiency, and kinetics of drug release are investigated by UV-vis spectroscopy. The loading efficiency of drug is 89% with a rapid release for the initial 7 h followed by the sustained release over a period of 36 h. The release of drug is envisaged to occur in response to the physiological temperature by deswelling of thermoresponsive PEO-PLGA-PEO block-copolymer. This study demonstrates that temperature can be exploited successfully as an external parameter to control the release of drug. [ABSTRACT FROM AUTHOR]

In this article, we describe a simple one-pot rapid synthesis route to produce uniform silver nanoparticles by thermal reduction of AgNO3 using oleylamine as reducing and capping agent. To enhance the dispersal ability of as-synthesized hydrophobic silver nanoparticles in water, while maintaining their unique properties, a facile phase transfer mechanism has been developed using biocompatible block co-polymer pluronic F-127. Formation of silver nanoparticles is confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV–vis spectroscopy. Hydrodynamic size and its distribution are obtained from dynamic light scattering (DLS). Hydrodynamic size and size distribution of as-synthesized and phase transferred silver nanoparticles are 8.2 ± 1.5 nm (σ = 18.3%) and 31.1 ± 4.5 nm (σ = 14.5%), respectively. Antimicrobial activities of hydrophilic silver nanoparticles is tested against two Gram positive ( Bacillus megaterium and Staphylococcus aureus), and three Gram negative ( Escherichia coli, Proteus vulgaris and Shigella sonnei) bacteria. Minimum inhibitory concentration (MIC) values obtained in the present study for the tested microorganisms are found much better than those reported for commercially available antibacterial agents. [ABSTRACT FROM AUTHOR]

Corrosion inhibition efficiency of Ocimum sanctum extract for mild steel in hydrochloric acid solution was studied by weight loss and thermometric methods. Inhibition efficiency increases with the increasing concentration of extract and decreases with increase in acid strength. Results of inhibition efficiency obtained by two methods have been found in good agreements with each other. Maximum inhibition efficiency was found 98.67% in 0.5 N HCl acid with 1.2% stem extract, whereas it was 96.02% in leaves extract with same concentration i.e. 1.2%. [ABSTRACT FROM AUTHOR]

We describe a simple one-pot thermal decomposition method for the production of a stable colloidal suspension of narrowly dispersed superparamagnetic Fe3O4-Ag core-shell nanostructures. These biocompatible nanostructures are highly toxic to microorganisms. Antimicrobial activity studies were carried out on both Gram negative ( Escherichia coli and Proteus vulgaris) and Gram positive ( Bacillus megaterium and Staphylococcus aureus) bacterial strains. Efforts have been made to understand the underlying molecular mechanism of such antibacterial actions. The effect of the core-shell nanostructures on Gram negative strains was found to be better than that observed for silver nanoparticles. The minimum inhibitory concentration (MIC) values of these nanostructures were found to be considerably lower than those of commercially available antibiotics. We attribute this enhanced antibacterial effect of the nanostructures to their stability as a colloid in the medium, which modulates the phosphotyrosine profile of the bacterial proteins and arrests bacterial growth. We also demonstrate that these core-shell nanostructures can be removed from the medium by means of an external magnetic field which provides a mechanism to prevent uncontrolled waste disposal of these potentially hazardous nanostructures. [ABSTRACT FROM AUTHOR]

Nanosized Mn1-xZnxFe2O4 (x = 0, 0·1, 0·3, 0·5, 0·6, 0·7, 0·9) mixed ferrite samples of particle size < 12 nm were prepared using the co-precipitation technique by doping the Zn2+ ion impurities. Autoclave was employed to maintain constant temperature of 80oC and a constant pressure. The X-ray analysis and the IR spectrum analysis were carried out to confirm the spinel phase formation as well as to ascertain the cation distribution in the ferrite samples. This clearly points to the fact that the Zn2+ ion's presence is not restricted to A-site alone for some of the Mn-Zn ferrite series. The real part of a.c. susceptibility measurements clearly indicated the superparamagnetic behaviour of the ferrite samples. There is a systematic decrease in the particle size, Curie temperature and magnetization with the increase in the Zn2+ ion doping, measured using magneto thermal gravimetric analysis (MTGA) and vibrating sample magnetometer (VSM), respectively. The lattice constant is found to be constantly decreasing till x = 0·6 and beyond this an unusual slight increase in the lattice constant is found. [ABSTRACT FROM AUTHOR]

A hydrothermal synthesis route is used to synthesize nanomagnetic particles of Co00:3Zn0:7Fe2O4 ferrite ferrofluids with particle diameter ranging from 5.5-9 nm. XRD analysis shows the formation of a single phase spinel structure. EDX results confirm the stoichiometric composition of the cations. Small angle neutron scattering technique is used to determine the size and size distribution of Co0:3Zn0:7Fe2O4 ferrofluid. The sizes thus obtained are in the range of 5.4 to 8.4 nm. These results are in agreement with magnetic measurements. [ABSTRACT FROM AUTHOR]

Cadmium ferrite particles have been synthesized using co-precipitation technique followed by a low temperature (600°C) annealing in a time scale much shorter than reported in literature. Incorporation of sodium chloride during annealing helps to form a single phase spinel structure with a final particle size of around 50 nm. Even at such a short length scale we observe the overall magnetic properties to be similar to those of the bulk. The observed magnetic properties can be explained on the basis of an anti-ferromagnetic core with a shell containing 'ferromagnetic-like', but canted spin structure. [ABSTRACT FROM AUTHOR]

Magnetite particles of different diameters were synthesized by chemical co-precipitation technique and the same are dispersed in dodecane to prepare a magnetic fluid. The results of X-ray diffraction, magnetization measurements, ac susceptibility and viscosity measurements are analyzed and discussed in the text. [ABSTRACT FROM AUTHOR]

Discusses a study conducted at Jayant mining block of Northern Coal Fields Ltd., on vesicular-arbuscular mycorrhizal association in naturally revegetated coal mine spoil. Information on how mycorrhizal fungus contribute to plant growth and survival; Role of mycorrhizae in stressed habitats; Description of the area, including the climate; Plant species studied.

The rheology of PP filled with three different types of fillers, namely synthetic sodium aluminium silicate (SSAS), aluminium silicate (AS) and calcium carbonate (CaCO3), at concentrations up to 40% was studied. Variation of shear and extensional viscosity was evaluated for all the compositions. When filler loading was less than 20%, the shear viscosity at low shear rates was less than that of virgin PP. Flow curves are described by the Ellis model. The onset of non-Newtonian shear thinning behaviour is related to parameter η10/τ1/2. Although fillers are white, they imparted a yellowish tone at lower loadings. At higher loadings, this yellowing effect was masked, yielding a lower yellowness index. [ABSTRACT FROM AUTHOR]

A numerical scheme based on the Finite Element Method has been developed which uses a relaxation factor in the momentum equation with the stresses being evaluated via a streamwise integration procedure. A constitutive equation introduced by Leonov has been used to represent the rheological behavior of the fluid. The convergence of the scheme has been tested on a 2 : 1 abrupt contraction problem by successive mesh refinement for non-dimensional characteristic shear rates, of 5 and 50 for polyisobutylene Vistanex at 27 °C. The recirculation region is shown to increase in size with non-dimensional characteristic shear rate. Theoretical predictions have been compared with the experimental data which include birefringence and pressure loss measurements. In general, the comparisons have been reasonably good and demonstrates the usefulness of the present numerical scheme and the Leonov constitutive equation to describe real polymer flows. [ABSTRACT FROM AUTHOR]

The viscoelastic behavior of polymeric systems based upon the Leonov model has been examined for (i) the stress growth at constant strain rate, (ii) the stress growth at constant speed and (iii) the elastic recovery in elongational flow. The model parameters have been determined from the available rheological data obtained either in steady shear flow (shear viscosity and first normal-stress difference as a function of shear rate) or oscillatory flow (storage and loss moduli as a function of frequency in the linear region) or from extensional flow at very small strain rates (time-dependent elongation viscosity in the linear viscoelastic limit). In addition, the effect of the parameter characterizing the strain-hardening of the material during elongation has also been studied. The estimation of this parameter has been based upon the structural characteristics of the polymer chain which include the critical molecular weight and molecular weight of an independent segment. Five different polymer melts have been considered with varying number of modes (maximum four modes). Resulting predictions are in fair agreement with corresponding experimental data in the literature. [ABSTRACT FROM AUTHOR]

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Copyright of Il Nuovo Cimento della Societa Italiana di Fisica: D is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Black Sigatoka is the most costly to control disease of bananas and plantains in the world. Currently, a worldwide search is underway either to find or to produce cultivars that are disease-resistant or-tolerant. Phytotoxins isolated from the pathogen might facilitate the discovery of such cultivars. Several aromatic compounds from liquid cultures of Mycosphaerella fijiensis, the causal agent of Black Sigatoka disease of bananas and plantains, have been isolated. The most abundant and phytotoxic of these compounds is 2,4,8-trihydroxytetralone, which induces necrotic lesions at 5 μg/5 μl in less than 12 h on sensitive cultivars of bananas. This compound exhibits host-selectivity that mimics that of the pathogen. Other phytotoxins isolated from this fungus, in lesser amounts, were juglone, the novel compound 2-carboxy-3-hydroxycinnamic acid, isoochracinic acid and 4-hydroxyscytalone. Some of the phytotoxins isolated are melanin shunt pathway metabolites, which makes this fungus unique among plant pathogens. [ABSTRACT FROM AUTHOR]

Two strains of Pseudomonas cepacia, RJ3 and ATCC 52796, have been identified as potential antagonists of fungal plant pathogens. We have compared the antagnonistic activity of these two strains against various fungal pathogens. Although both strains displayed high levels of antagonism, ATCC 52796 was slightly more antagonistic than RJ3. The antagonist from RJ3 has been identified as the antifungal compound pyrrolnitrin after purification by HPLC and characterization by UV, IR, NMR, and mass spectroscopy. Both strains also antagonized the fungi by production of volatile compound(s), which have not yet been identified. Both strains are similar with respect to in vitro antagonism, mechanism of antagonism, and sensitivity to antibiotics. [ABSTRACT FROM AUTHOR]

Pseudomonas cepacia, a common soil and rhizosphere inhabitant, showed strong antagonism against several fungal plant pathogens. In dual cultures it greatly restricted the growth and conidial formation in several of these fungi. Growth restriction was associated with the frequent induction of a variety of morphological abnormalities such as chlamydoconidium formation, hyphal swellings, vacuolation and granulation of the mycelial contents, as well as lysis of hyphae and conidia. The induction of these deleterious morphological changes in fungi and inhibition of conidial formation were also found with a crude preparation of an antifungal compound from P. cepacia. Mutants, defective in the production of this antifungal compound, failed to induce these morphological changes; this suggests that the antifungal compound is responsible for these abnormalities. [ABSTRACT FROM AUTHOR]

Chelates of bidentate ligands, p-dimethylamino and p-diethylaminoanils of 3-benzoylmethylglyoxal with Ir(III), Pt(IV) and Au(III) ions have been studied for their stoichiometry, electrolytic nature, infrared, magnetic, and electronic spectra. In addition to the elucidation of stereochemistry and structures various ligand field parameters have been calculated and unusual paramagnetic behaviour has been accounted for. [ABSTRACT FROM AUTHOR]

Low spin square planar complexes of Au(III) with five keto anils as ligands have been investigated spectroscopically. Several bands corresponding to d-d and L→M charge transfer transitions have been identified following the 'Molecular Orbital Scheme' given by Gray and Ballhausen. Square planar geometry established spectroscopically has been confirmed magnetically. Os(VIII) complexes involving d configuration have also been studied and found having octahedral stereochemistry. Infrared spectra of ligands and complexes have been used to determine their structures and seats of coordination. [ABSTRACT FROM AUTHOR]

Thin layer chromatographic behaviour of ten anils was studied on silica gel adsorbent mixed with starch binder with ten solvent systems. Simultaneous separation, identification and determination of ternary mixtures of isomers was stressed. The R increasing order was found to be dependent on the solvent and independent of the degree of saturation of the chamber. The correlations of R with λ and ν (C=O) of isomers were established and used in their identification. Six anils were separated in methanol-benzene (1∶1). [ABSTRACT FROM AUTHOR]