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In this study, a hybrid dual drug-loaded hydroxyapatite-oxidized dextran methacrylate core–shell nanocarrier was formulated and explored for combinatorial delivery of doxorubicin (DOX) and methotrexate (MTX) to bone cancer. The synthesized nanocarrier was well characterized by different techniques. In vitro drug release studies in both acidic (pH 5) and alkaline (pH 7.4) conditions showed sequential release of MTX followed by DOX in a sustained manner for 10 days. Biocompatibility and cytotoxicity studies performed using drug-loaded nanoparticles (NPs) on fibroblast L929 cells and osteosarcoma MG63 cells (OMG63) showed that the NPs were highly biocompatible and showed concentration-dependent toxicity. Gene expression studies in OMG-63 cells exhibited the upregulation of caspase-3 and BAX which confirmed the apoptosis induced by dual drug-loaded NPs. The nanocarrier is expected to be a potential bone void filling material, as well as a platform for sequential delivery of DOX and MTX for the treatment of bone cancer.
Five species of Eremothecella are recorded from the Andaman Islands, two of which are described as new: Eremothecella ajaysinghii Jagad. Ram & G. P. Sinha and E. nicobarica Jagad. Ram & G. P. Sinha. Eremothecella ajaysinghii has whitish grey, pruinose ascomata and 8–10(–11)-septate ascospores, while E. nicobarica has non-pruinose ascomata and (14–)15–17-septate ascospores. Eremothecella calamicola Syd., E. macrosperma (Zahlbr.) Sérus. and E. variratae (Aptroot & Sipman) Sérus. are reported as new records for India. An updated worldwide key to species of the genus is presented.
The present work aims to understand the effect of zinc and rare-earth element addition (i.e., 2 wt% Gd, 2 wt% Dy, and 2 wt% of Gd and Nd individually) on the microstructure evolution, mechanical properties, in vitro corrosion behavior, and cytotoxicity of Mg for biomedical application. The microstructure results indicate that the Mg–Zn–Gd alloy consists of the lamellar long period stacking ordered phase. The electrochemical and immersion corrosion behavior were studied in Hanks balanced salt solution. Enhanced corrosion resistance with reduced hydrogen evolution volume and magnesium (Mg2+) ion release were estimated for the Mg–Zn–Gd alloy as compared to the other two alloy systems. At the early stage of corrosion, formation of the oxide film inhibited the corrosion propagation. However, at the later stages, the breaking of the oxide film leads to shallow pitting mode of corrosion. The ultimate tensile strength of Mg–Zn–Gd–Nd is better than the other two alloys due to the uniform distribution of the Mg12Nd precipitate phase. The moderate strength in the Mg–Zn–Gd alloy is due to the low volume fraction of the secondary phase. The MTT (methylthiazoldiphenyl-tetrazolium bromide) assay study was carried out to understand the cell cytotoxicity on the alloy surfaces. Studies revealed that all three alloys had significant cellular adherence and no adverse effect on cells.
Research focus in recent years on magnetic behaviour of transition metal (TM) ions embedded in semiconductors has shifted from intrinsic effects to extrinsic effects such as the formation of nanoclusters of the TM ions and the influence of the host matrix on their magnetic behaviour. Our studies, using conversion electron Mössbauer Spectroscopy and magnetization measurements, on SiO2 and Al2O3 substrates implanted with 4 at. % Fe, show ferromagnetic behaviour of α-Fe clusters in amorphous SiO2, but α-Fe2O3 clusters displaying superparamagnetic relaxation in crystalline Al2O3.
Photovoltaic (PV) systems are progressively used for decentralized electricity generation. To obtain the maximum yield from such systems, optimisation of all components is essential. In this contribution, we provide a comprehensive modelling and sizing of PV systems for any location. Three applications are here presented providing real time monitoring of PV potential, accurate prediction of yield taking into account thermodynamic temperature effects, optimization of modules orientation addressing the effects of shading and efficient sizing of inverter for a higher yield output. When combined, these models can accurately predict the real time performance of any PV system.
We report on the structural and electrical characteristics of bulk and thin film of ternary oxide SmGdO3. Bulk sample of SmGdO3 was prepared by pelletizing and sintering the calcined mixture of predetermined amount of Sm2O3 and Gd2O3 powders. The crystalline structure of the sample was studied by X-ray diffraction measurements and Raman spectroscopy. Capacitance and leakage current measurements on bulk sample revealed a high and linear dielectric constant of ∼ 19 with low dielectric loss and leakage current which is suitable for gate dielectric application in CMOS logic devices and high-k MIM capacitors. In addition, the non-volatile resistive memory switching phenomenon was studied in thin films of SmGdO3 which were deposited by pulsed laser deposition using sintered pellet of SmGdO3 as target. Commercially available Pt/TiO2/SiO2/(100) Si was used as substrate and top Pt electrode of lateral dimension 40×40μm2 were deposited by sputtering to construct Pt/SmGdO3/Pt MIM devices. After initial forming process which occurred at comparatively higher voltage, the Pt/SmGdO3/Pt devices showed repeatable unipolar switching between high and low resistance states with low and well defined switching voltages. These properties indicate suitability of this material for the emerging logic and memory device applications.
Eight species of Herpothallon are recorded from the Andaman Islands, four of which are described as new: Herpothallon coralloides, H. globuliferum, H. lutescens and H. minutum. All these new species have a non-pigmented thallus, prothallus, hypothallus and pseudisidia. Herpothallon coralloides and H. lutescens possess cylindrical pseudisidia whereas H. globuliferum and H. minutum have granular to globose pseudisidia. Herpothallon globuliferum is foliicolous. Herpothallon echinatum, H. granulare, H. granulosum and H. philippinum are reported for the first time from the Andaman Islands. A key to the Indian species is provided. Heiomasia pallescens (Graphidaceae), a byssoid taxon with a disc-shaped isidioid structure, is also described as new to science.
As part of a census of the Indian rhinoceros Rhinoceros unicornis a survey was conducted to measure the extent of invasion by the neotropical plant mikania Mikania micrantha across major habitats of Chitwan National Park important for the conservation of the rhinoceros. Previous work has demonstrated that this fire-adapted plant can smother and kill native flora such as grasses and sapling trees, several of which are important fodder plants of the rhinoceros. Here, additional studies were conducted on the risks of anthropogenic factors (natural resource collection and grassland burning) contributing to the spread and growth of the plant. Mikania is currently found across 44% of habitats sampled and almost 15% of these have a high infestation (> 50% coverage). Highest densities were recorded from riverine forest, tall grass and wetland habitats and this is where the highest numbers of rhinoceroses were recorded in the habitats surveyed during the census. Local community dependence on natural resources in the core area of the Park is high. The range and volume of resources (e.g. fodder) collected and the distances travelled all pose a high risk of the spread of mikania. Of greater significance is the annual burning of the grasslands in the Park by local communities, estimated at 25–50% of the total area. It is imperative, therefore, that core elements of a management plan for mikania incorporate actions to control burning, reduce spread and raise awareness about best practice for local resource management by local communities.
The UBVRI photometric follow-up of SN 2011fu has been initiated a few days after the explosion, shows a rise followed by steep decay in all bands and shares properties very similar to that seen in case of SN 1993J, with a possible detection of the adiabatic cooling phase at very early epochs. The spectral modeling performed with SYNOW suggests that the early-phase line velocities for H and Fe ii features were ~ 16000 km s−1 and ~ 14000 km s−1, respectively. Studies of rare class of type IIb SNe are important to understand the evolution of the possible progenitors of core-collapse SNe in more details.
A number of factors contribute to the lack of access to modern forms of energy. They include low income levels, unequal income distribution, inequitable distribution of modern forms of energy, a lack of financial resources to build the necessary infrastructure, weak institutional and legal frameworks, and a lack of political commitment to the scaling up of services. An absence of specific policies oriented to poverty alleviation often explains inequitable economic growth and, consequently, inequality in access to and use of energy. In recent years, several developing countries have defined targets aimed at improving access to electricity, but many developing countries still have no modern forms of energy access targets in place that address meeting basic energy services, including modern fuels for cooking and mechanical power.
As Chapter 2 argues, developing countries require adequate access to modern energy, especially among the poor, in order to meet the Millennium Development Goals (MDGs) as well as their own national development objectives. In line with GEA objectives, Chapter 17 pathways are designed to describe transformative changes toward a more sustainable future. A specific feature of the GEA energy transition pathways is that they simultaneously achieve normative goals related to all major energy challenges, including environmental impacts of energy conversion and use, as well as energy security and energy access. ‘Energy access’ refers to those challenges clearly described in Chapter 19, which will be addressed in this chapter.
Affordable and sustainable universal access to modern forms of energy depends on the evolution of income level and income distribution.
In the present work we report the synthesis of Cu2ZnSnS4 (CZTS) films by pulsed laser deposition (PLD) and the effect of sulfur annealing on structure, composition, morphological and optical characterization of CZTS thin films. Raman spectra of the films exhibited the characteristics peaks of Kesterite structure. However, annealing caused to transfer the films from amorphous state into crystalline state. Scanning electron microscope (SEM) images revealed that as-deposited film exhibited a crack free, smooth, densely packed and homogeneous surface which was changed to rigid granular appearance after annealing. Energy dispersive X-ray spectroscopy (EDS) determined the compositions of the CZTS thin films which was near stoichiometry for the annealed samples. Ultraviolet–visible (UV–Vis) spectra showed the band gap of as-deposited film was 1.60 eV which was decreased to 1.40 eV after annealing.
In this work we present the synthesis, characterization and application of the nanodiamond- polypyrrole nanocomposite films as electrochemical active electrode for sensing cholesterol. Cholesterol oxidase and esterase have been covalently attached to the surface of the films. Results showed that the inclusion of nanodiamond to the polymeric matrix increment the surface area and provide carboxylic groups capable to perform reaction with the amide groups present in the enzymes. Further, the sensitivity of the electrode to the cholesterol content have been examined.
The cultivar Ajaya (IET 8585) exhibits durable broad-spectrum resistance to bacterial blight (BB) disease of rice and is widely used as a resistance donor. The present study was carried out to decipher the genetics of BB resistance in Ajaya and map the gene(s) conferring resistance. Genetic analysis in the F2 indicated a quantitative/additive nature of resistance governed by two loci with equal effects. Linked marker analysis and allelic tests revealed that one of the resistance genes is xa5. Sequence analysis of a 244 bp region of the second exon of the gene-encoding Transcription factor IIAγ (the candidate gene for xa5) confirmed the presence of xa5. Bulked-segregant analysis (BSA) revealed the putative location of the two quantitative trait loci (QTLs)/genes associated with resistance on chromosomes 5 and 8. Composite interval mapping located the first locus on Chr. 5S exactly in the genomic region spanned by xa5 and the second locus (qtl BBR 8.1) on Chr. 8L. Owing to its differential disease reaction with a set of seven hyper-virulent isolates of Xanthomonas oryzae, a map location on Chr. 8L, which was distinct from xa13 and data from allelism tests, the second resistance locus in Ajaya was determined to be novel and was designated as xaAj. A contig map spanning xaAj was constructed in silico and the genomic region was delimited to a 13·5 kb physical interval. In silico analysis of the genomic region spanning xaAj identified four putatively expressed candidate genes, one of which could be involved in imparting BB resistance in Ajaya along with xa5.
We present a theoretical investigation of the thermoelectric power factor enhancement in metal/semiconductor nanocomposites by the energy dependent electron scattering from ionized nanoparticles. The metal nanoparticles embedded in semiconductors can be ionized to donate electrons to the matrix, which will result in a Coulomb potential tail around the nanoparticles. Here we show the significant effect of slowly varying potential tails on thermoelectric properties of the nanocomposites. The Coulomb potential is different from that of the conventional ionized impurities due to the finite size of the ionized particles, and the fact that the nanoparticles can give multiple electrons to the matrix. Detailed calculations for scattering rates and thermoelectric coefficients are presented for ErAs semi-metallic nanoparticles in InGaAs semiconductors. The partial wave method is used to consider the exact potential profile around nanoparticles and Boltzmann transport equation is used to calculate the transport coefficients. We find that an increase by 15~30% in power factor can be achieved over a wide temperature range in these material systems in addition to the thermal conductivity reduction to further enhance ZT.
A new lichen species, Pyrenula darjeelingensis (Pyrenulaceae), is described from the Eastern Himalayan region of India. It is characterized by having 5-septate to submuriform ascospores with papillate apices and the terminal lumina mostly not separated from the exospore by an endospore layer. Six additional species of Pyrenula are reported for the first time from India: P. acutalis R. C. Harris, P. dermatodes (Borrer) Schaer., P. mastophoroides (Nyl.) Zahlbr., P. mucosa (Vain.) R. C. Harris, P. subelliptica (Tuck.) R. C. Harris and P. thelemorpha Tuck.
Five new species of Cryptothecia: C. alboglauca, C. bengalensis, C. farinosa, C. multipunctata and C. verruculifera, and two new species of Herpothallon: H. granulosum and H. isidiatum are described from India. Herpothallon australasicum (Elix) Elix & G. Thor and H. granulare (Sipman) Aptroot & Lücking are also reported as new records.
Enterographa bengalensis, a new species is described from the mangrove reserve – Sundarbans Biosphere Reserve, West Bengal, India. It is characterized by the convergent punctiform to lirelliform ascomata, 12–15(–17) septate fusiform ascospores and the presence of psoromic acid. In addition, three species of the genus viz. E. anguinella (Nyl.) Redinger, E. divergens (Müll. Arg.) Redinger and E. multiseptata R. Sant. are also reported for the first time from India.