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Introduction: Diabetes mellitus (DM) is a metabolic disorder that results in glucose accumulation in the blood, accompanied by the production of advanced glycation end products (AGEs) through glycation of cellular proteins. These AGEs interfere with insulin signaling and prevent GLUT4 membrane translocation, thereby promoting the accumulation of more glucose in the blood and causing post-diabetic complications.Methods: In this study, we examine the anti-diabetic potential of Lyonia ovalifolia (Wall.) Drude, a well-known ethnomedicinal plant of the Indian Himalayas. Considering its various medicinal properties, we analyzed its ethanolic extract and various solvent fractions for in vitro antiglycation activity and antidiabetic potential, i.e., stimulation of GLUT4 translocation.Result and Discussions: The results showed that the extract and fractions exhibited increased antiglycation activity and an increased level of GLUT4 translocation. Analysis of a further 12 bioactive compounds of ethanolic extract, identified through LC-ESI-QTOF-MS/MS, revealed the presence of three new compounds: leucothol B, rhodoterpenoids A, and leucothol A. Moreover, we performed molecular docking of identified compounds against key proteins of diabetes mellitus: the sirtuin family of NAD (+)-dependent protein deacetylases 6 (SIRT6), aldose reductase (AR), and tyrosine kinase (TK). The results showed that flavonoid luteolin showed the best binding affinity ((−12.3 kcal/mol), followed by eriodictyol, astilbin, and syringaresinol. An ADMET study showed that luteolin, eriodictyol, astilbin, and syringaresinol may be promising drug candidates belonging to the flavonoid class of compounds, with no harmful effects and complying with all the drug-likeness guidelines. Furthermore, molecular dynamics (MD) simulations on a 50 ns timescale revealed that AR protein was most stable with luteolin throughout the simulation period. Therefore, this study reveals for the first time that L. ovalifolia plays an important role in insulin homeostasis, as shown in in vitro and in silico studies.

We present photometric and kinematic analysis of an intermediate age open cluster NGC 1027 using $UBV(RI)_c$ and Gaia Early Data Release 3 (EDR3) data. Structural and fundamental parameters such as cluster center, cluster extent, reddening, age and distance are estimated in this study. Cluster center is found about 2 arcmin away from the center reported earlier. Radius has been estimated to be about 8.00 arcmin(2.65pc). Using proper motion Gaia EDR3 data, membership probabilities has been derived for the stars in the region of cluster radius. We find mean proper motion of the cluster to be $\sim$(-0.84, 2.04) mas yr$^{-1}$ in (RA, DEC). We find 217 most probable (P$_\mu>$ 70\%) cluster members with mean parallax 0.892 $\pm$ 0.088 mas. Out of these, 160 members have counterparts in our optical observations. Few stars having P$_\mu>$ 70\% are found out of the cluster radius showing imprints of dynamical evolution. The color-color and color-magnitude diagrams for the cluster members found within 8.00 arcmin have been constructed using $UBV(RI)_c$ photometry and Gaia EDR3 data. This yields a reddening E($B$-$V$) $\sim$ 0.36 mag, age $\sim$ 130 Myr and distance $\sim$ 1.14 kpc. The mass function slope in the cluster region is $\Gamma$ $\sim$ -1.46 $\pm$ 0.15, which is similar to other Galactic open clusters. The dynamical study shows lack of faint stars in its inner region leading to mass segregation effect. A comparison of dynamical age with cluster age indicates that NGC 1027 is a dynamically relaxed cluster suggesting that mass segregation may be imprint of its dynamical relaxation.

We present the idea of emergent qubits by exact constructions. We rigorously transform the toric code model into a problem of emergent qubits, and write all its eigenstates exactly. As byproducts of this exercise, we introduce a punctured version of the model on torus and an open version on cylinder, both realizing independent emergent qubits perfectly. The exact eigenstates of the toric code and other models are shown to be realized by applying CNOT gates on independent qubits., Comment: 4 pages, 4 figures

Background: Organic Light Emitting Diodes have emerged as a potential candidate for being used as the display because of their remarkable performance. In the past decade, a lot of interest was shown in their development and improvement. Scientists utilized different methods for enhancing their performance which included the change in OLEDs architecture. Different supporting layers (charge injection, transportation and blocking) are added in the architecture to enhance the performance of OLED. Some of the patents related to the application of the OLED have also been reviewed to observe the utilization of the present work in those applications. Objective: The motive of this research article is to analyze impacts the impact of different layers on the performance of OLED. Methods: The objective is achieved by systematically analyzing the impact of different layers on the OLED. The analysis commenced by investigating the properties of the basic OLED consisting of the emission layer only. Thereafter, in succession different supporting layers are added to the OLED architecture. Subsequently, after adding each layer, OLED device is analyzed and its properties are determined. Finally, the performance of different layers is compared. Results: The outcome of the above research study shows that these supporting layers are significantly able to enhance the performance of the OLED. Step by step layers are added to the architecture and enhancement in the performance is observed. There is an improvement of 13% to 38% not over the basic OLED architecture, but over the multilayered OLED device, which is already far better than the basic OLED. Conclusion: Therefore, from the analyses, it can be concluded that the different layers are significant for the OLED architecture and improve the performance of the OLED considerably.

Although the field of 2D materials has democratized materials science by making high quality samples accessible cheaply, due to the atomically thin nature of these systems, an integration with nanostructures is almost always required to obtain a significant optical response. Traditionally, these nanostructures are fabricated via electron beam lithography or focused ion beam milling, which are expensive and large area fabrication can be further time consuming. In order to overcome this problem, we report the integration of 2D semiconductors on a cost-effective and large area fabricated nanocone platform. We show that the plasmon modes of our nanocone structures lead to photoluminescence (PL) enhancement of monolayer WSe$_2$ by about eight to ten times compared to the non-plasmonic case, consistent with finite-difference time-domain simulations. Excitation power-dependent measurements reveal that our nanocone platform enables a versatile route to engineering the relative exciton trion contributions to the emission.

Strong coupling of excitons to optical cavity modes is of immense importance to understanding the fundamental physics of quantum electrodynamics at the nanoscale as well as for practical applications in quantum information technologies. There have been several attempts at achieving strong coupling between excitons in two dimensional semiconductors such as transition metal dichalcogenides (TMDCs) and photonic quasi-bound states in the continuum (BICs). We identify two gaps in the platforms for achieving strong coupling between TMDC excitons and photonic quasi-BICs: firstly, in the studies so far, different cavity architectures have been employed for coupling to different TMDCs. This would mean that typically, the fabrication process flow for the cavities will need to be modified as one moves from one TMDC to the other, which can limit the technological progress in the field. Secondly, there has been no discussion of the impact of fabrication imperfections in the studies on strong coupling of these subsystems so far. In this work, we address these two questions by optimizing a cavity with the same architecture which can couple to the four typical TMDCs (MoS$_2$, WS$_2$, MoSe$_2$, WSe$_2$) and perform a detailed investigation on the fabrication tolerance of the associated photonic quasi-BICs and their impact on strong coupling.

High resolution infrared imaging observations of the young Planetary Nebulae NGC 7027 and BD +303639, taken with the newly installed TIFR Infrared Camera-II (TIRCAM2) on 3.6m Devasthal Optical Telescope (DOT), ARIES, Nainital, are being reported. The images are acquired in J, H, K, polycyclic aromatic hydrocarbon (PAH) and narrow-band L (nbL) filters. The observations show emission from warm dust and PAHs in the circumstellar shells. The imaging of the two objects are among the first observations in PAH and nbL bands using TIRCAM2 on DOT. The NGC 7027 images in all bands show similar elliptical morphology with ~6".7 and ~4".5 semi-major and semi-minor axes. Considering size up to 10% of peak value the nebula extends upto 8" from the central star revealing a multipolar evolution. The relatively cooler BD +303639 shows a rectangular-ring shaped nebula. In J and H bands it shows an angular diameter of ~8", while a smaller ~6".9 size is observed in K, PAH and nbL bands. The 3.28 micron emission indicates presence of PAHs at about 6000 and 5000 AU from the central stars in NGC 7027 and BD +303639 respectively. Analysis suggests domination of neutral PAHs in BD+303639, while in NGC 7027 there is higher ionization and more processed PAH population., Comment: 8 Figures, 5 Tables accepted in J of Astronomy and Astrophysics

A non-descript doe in its 7 th. parity was presented with the history of 5 months and 5 days gestation period showing futile signs of imminent kidding with teat engorgement and vaginal discharge from last 12 hours but no delivery of fetus. The gynecological examination of the doe revealed an engaged fetus in the birth canal with simultaneous presence of a hard-rubbery structure. Gentle traction was applied using small eye hook following proper lubrication of the birth canal and triplet comprising of two mature but dead and one mummified fetus were delivered. The case highlights the rare occurrence of one mummified fetus as co-triplet with two mature fetuses in the simultaneous presentation causing dystocia in doe.

India and Belgium have jointly established two 4-meter class optical telescopes at Devasthal located in Nainital, India. After successful installation of the 3.6-m modern new technology Devasthal Optical Telescope (DOT) in 2015, it was technically activated by premiers of both countries from Brussels on March 30, 2016. Since then, the 3.6-m DOT has been used for both optical and near-Infrared (NIR) observations for a number of research proposals. The best angular resolution achieved is 0″.4 indicating that the optics of the 3.6-m DOT is good and capable of providing images of celestial bodies with sub-arc-second resolution. The observations provide proof that the care taken in the construction of the telescope dome building has paid a rich dividend as their thermal mass is so low that it has not degraded the natural atmospheric seeing at Devasthal measured about two decades ago during 1997 to 1999 using differential image motion monitor. A few preliminary scientific results obtained from recent observations are presented along with performance and global potential of the 3.6-m DOT in the field of galactic astronomy. The 3.6-m DOT is capable of providing internationally competitive science once high resolution spectrograph and other planned modern back-end instruments become operational. Geographical location of the observatory has global importance for time domain and multi-wavelength astrophysical studies.

We asked young scientists this question: How has your awareness of science inspired you to adopt more sustainable and environmentally friendly behavior? Respondents from around the world described scientifi c concepts, images, and research from a range of fi elds that inspire them to make environmentally friendly decisions and model sustainable behavior for others, in both their personal and professional lives.

Spinacia oleracea L. (Spinach) is a leafy vegetable which is considered to have a high nutritional value. Flavonoids in spinach were reported to act as antimutagenic property. Rapid detection of these flavonoids in Spinach was achieved by using HPLC-ESI-QTOF-MS/MS. Thirty six compounds were tentatively identified based on their retention times, accurate mass and MS/MS spectra. The fragmentation patterns of known compounds were applied to elucidate the structure of their corresponding derivatives having the same basic skeleton. Out of thirty six peaks, three peaks were assigned as patuletin and six peaks were assigned as spinacetin derivatives. Twelve compounds were first time identified following the fragmentation pattern of known compounds. Five of the identified compounds i.e., spinacetin, 5,3',4'-trihydroxy-3-methoxy-6,7-methylenedioxyflavone, protocatechuic acid, ferulic acid and coumaric acid were simultaneously quantified in spinach leaves by a validated UPLC-ESI-MS/MS method under MRM mode.

TIFR Near Infrared Imaging Camera-II is a closed-cycle Helium cryo-cooled imaging camera equipped with a Raytheon 512 x 512 pixels InSb Aladdin III Quadrant focal plane array having sensitivity to photons in the 1-5 microns wavelength band. In this paper, we present the performance of the camera on the newly installed 3.6-m Devasthal Optical Telescope (DOT) based on the calibration observations carried out during 2017 May 11-14 and 2017 October 7-31. After the preliminary characterization, the camera has been released to the Indian and Belgian astronomical community for science observations since 2017 May. The camera offers a field-of-view of ~86.5 arcsec x 86.5 arcsec on the DOT with a pixel scale of 0.169 arcsec. The seeing at the telescope site in the near-infrared bands is typically sub-arcsecond with the best seeing of ~0.45 arcsec realized in the near-infrared K-band on 2017 October 16. The camera is found to be capable of deep observations in the J, H and K bands comparable to other 4-m class telescopes available world-wide. Another highlight of this camera is the observational capability for sources up to Wide-field Infrared Survey Explorer (WISE) W1-band (3.4 microns) magnitudes of 9.2 in the narrow L-band (nbL; lambda_{cen} ~3.59 microns). Hence, the camera could be a good complementary instrument to observe the bright nbL-band sources that are saturated in the Spitzer-Infrared Array Camera ([3.6], 16 pages, 12 figures, 1 table, Accepted for publication in the Journal of Astronomical Instrumentation

The idea of starting an astronomical observatory in the state of Uttar Pradesh in India germinated through the initiative of a scholarly statesman Babu Sampurnanandji. His interest in astrology coupled with his academic bent of mind got him interested in modern astronomy. Being then Education Minister and later Chief Minister of Uttar Pradesh, he established an astronomical observatory at Varanasi on April 20, 1954. Later on it was shifted to Manora Peak, Nainital. Four reflectors were commissioned at Manora Peak. For solar research an H alpha petrol unit and a horizontal solar spectrograph was setup. A detailed project report for installation of a 4-m class optical telescope was prepared indigenously in late 1980, however, the project could not take off. With the generous support of the Department of Science and Technology, the institute established a 3.6-m new technology optical telescope and a 1.3-m wide field optical telescope at a new observing site called Devasthal. Now a 4-m liquid mirror telescope is also being installed at the same observing site. I present here a brief journey of the observatory beginning right from its birth in 1954 till now.

We present optical photometric (upto  410 days since Bmax) and spectroscopic (upto  235 days since Bmax) observations of a type Iax supernova SN 2014dt located in M61. The broad band light curves follow a linear decline upto  100 days after which a significant flattening is seen in the late-time (beyond 150 days) light curves of SN 2014dt. SN 2014dt best matches the light curve evolution of SN 2005hk and reaches a peak magnitude of MB -18.12±0.04 with m15 1.35±0.06 mag. The earliest spectrum at  23 days is dominated by FeII and CoII lines with the absence of the Si II 6150 Å line. Using the peak bolometric luminosity we estimate a 56Ni mass of 0.14 M in the case of SN 2005hk and the striking similarity between SN 2014dt and SN 2005hk implies that a comparable amount of 56Ni would have been synthesized in the explosion of SN 2014dt. There are several explosion scenarios proposed for these peculiar events. Being one of the brightest and closest SN, SN 2014dt is an ideal candidate for long term monitoring. Late phase observations are very essential to understand the progenitor system and the actual explosion scenario for these events.

Stripped-Envelope Supernovae constitute the sub-class of core-collapse supernovae that strip off their outer hydrogen envelope due to high stellar winds or due to interaction with a binary companion where mass transfer occurs as a result of Roche lobe overflow. We present here the photometric and spectroscopic analysis of a member of this class : SN 2015as classified as a type IIb supernova. Light curve features are similar to those of SN 2011fu while spectroscopic features are quite similar to those of SN 2008ax and SN 2011dh. Early epoch spectra have been modelled with SYN++ which indicates a photospheric velocity of 8500 km sec-1 and temperature of 6500K. Spectroscopic lines show transitioning from H to He features confirming it to be a type IIb supernova. Prominent oxygen and calcium emission features are indicative of the asymmetry of the ejecta. We also estimate the signal to noise ratio of the 3.6m telescope data. This telescope is located at ARIES, Devasthal, Nainital at an altitude of 2450m. We also show the comparison plots of spectra taken with a 2m and 4m class telescopes to enlighten the importance of spectral features displayed by bigger diameter telescopes.

The type II supernovae (SNe) are hydrogen-rich cosmic explosions resulting from the collapse of massive stars. The impetus of studying individual events arises from its cosmological importance and the diverse understanding of the evolution and explosion mechanism of such events. In this work, we present the preliminary photometric and spectroscopic analysis of a recent type IIP explosion, PNV J01315945+3328458 in the galaxy NGC 582. While the initial phases of these energetic events are bright enough to be observed with the 1-2m class telescopes, the supernovae fade below the detection limit of these telescopes in the nebular phase. In addition, the class of sub-luminous events with Mv  -15 or the events occurring at higher redshift, fade below the detection limit of these telescopes very early in their evolution. Large aperture telescopes like the newly installed 3.6m Devasthal Optical Telescope (DOT) will ensure a longer coverage of such events and also to probe deeper into the Universe. With the 3.6m telescope installed in Devasthal (DOT), we plan to study the progenitor environment of CCSNe to infer the metallicity at the explosion site.

We present a brief description of the activities of the infrared astronomy group of Tata Institute of Fundamental Research with special emphasis on the ground-based near infrared instrumentation for star formation studies. We describe the unique capability of TIRCAM2 for observations in the polycyclic aromatic hydrocarbon (λcen∼ 3.3 μm) and narrow-band L (λcen∼ 3.59 μm) bands, currently being used by the astronomy community, and of the upcoming TANSPEC, which is being built for India’s largest telescope, i.e. the 3.6-m Devasthal Optical Telescope (DOT). The TIRCAM2 on the 3.6-m DOT was successfully commissioned in June 2016, and the subsequent characterization and astronomical observations are presented here. Based on the successful engineering runs on the 3.6-m DOT, TIRCAM2 has been made available to the Indian and Belgian astronomical community for science observations since Early Science Cycle 2017A (May 2017) onwards. The fabrication of TANSPEC is in an advanced stage and the spectrometer is expected to be commissioned by the end of January 2018.

We present an update on the 3.6-m aperture optical telescope, which has been installed at Devasthal in the year 2016. In this paper, a brief overview of installation activities at site and first results are presented. The 3.6-m Devasthal Optical Telescope project was initiated in 2007 by the Aryabhatta Research Institute of Observational Sciences (ARIES; Nainital, India) in partnership with Belgium. The telescope has Ritchey-Chretien optics, an alt-azimuth mount, an active control of the primary and a corrected science field of view of 30\' at the Cassegrain focus. The construction of the telescope enclosure building was completed in June 2014 and after successful installation of the telescope. The first engineering light was obtained on 22 March 2015. The on-sky performance of the telescope was carried out till February 2016.

Sports and games have always been instrumental in the physical, moral and spiritual development of people. Their worth has been accepted throughout the world by our best teachers, social reformers and religious saints. Sports and games provide opportunities to an individual to develop his/her physical strength, endurance and capacity so that the body can be able to bear any impending problem. Swami Vivekananda asserts, “You will be nearer to Heaven through football than through the study of the Gita” (qtd. in Murty 5). Sports and Games inculcate positive traits in students who use them not only inside the field but out of it. A sportsperson learns by following paradigms of their seniors and other best players of the world across various games. Hs/she knows it better that sport events are as for the winning the games as they are for winning the hearts of the people and the competitors. A medal with dishonesty is looked down upon therefore; no player wants to receive it. Fair Play Trophy/ Award in each and every big international game is provided to develop good moral values in the sportspersons. Morality and sports are intertwined to each other because sports develop moral values which in turn shape the personality of an individual.

The Hida model, defined on honeycomb lattice, is a spin-1/2 Heisenberg model of aniferromagnetic hexagons (with nearest-neighbor interaction, $J_A>0$) coupled via ferromagnetic bonds (with exchange interaction, $J_F, 16+ pages, 11 figures

by Brijesh Kumar,Atul Bhargav and Patrick Ruch

Girls have always been targeted in the name of good conduct, normal human behavior, social and religious norms since centuries. These norms have created good women and bad women i.e. those who abide by the various rules of the society are supposed to be normally good whereas those who resist and want to create their own rules of life are dubbed as abnormal anti-social bad girls. Working girls in metro cities have been the soft target for these feudal minded people. They guess that such girls are easily available because they are coming out of their houses for enjoyment and not for work. Aniruddha Roy Chowdhury’s movie, Pink, depicts this illegal, unethical physical and psychological exploitation of three working girls- Meenal Arora (Taapsee Pannu), Falak Ali (Kriti Kulhari) and Andrea (Andrea Tariang). It is the story of these three girls who opt to live in a rented house in order to earn their livelihood and be self-independent in a posh colony of South Delhi. They suffer a lot not because of their own reasons but because of the various social structures. These social structures prove to be the chief reasons behind their exploitation. Johan Gultung, a Norwegian sociologist and the principal founder of the discipline of the Peace and Conflict Studies, points out towards various social and religious structures which curtail the freedom of those people who deviate from such structures. Thus, these structures inflict violence on people without any clear actor behind it. This movie has shown various such social norms which become violent for the working girls.

And Such Is Her Fate is a Sahitya Academy Award winning novel of Dalip Kaur Tiwana, a renowned Punjabi writer. It depicts the tragic life of the female protagonist, Bhano who represents the pathetic condition of most of the marginalized Indian women. She is such a woman who is exploited and oppressed by her family and almost by all those who come in contact with her. Her father sold her to save the life of her brother. She has no other option but to accept whatever her fate decrees upon her. Sarban, her husband, loves her but his untimely death pushes her again in the darkness of the world. When she hears that her father wants to sell her again, she runs away from the home with the intention to commit suicide. When she is about to jump into the river, Narain, a drunkard, saves her and accepts her as his unwedded wife. She has managed his house so beautifully that most of the women in her locality, feel jealous. Many young boys have their lustful eyes set on her but she saves her dignity from everyone. But God has some other plan for her. When she does not bear children for Narain, he leaves her at the instigation of one of his relatives and marries to Bhagwanti, another woman, who ultimatelty bears a baby boy for him. After giving birth to a son, she becomes Narain’s true wife in the male dominated society. This event has pushed Bhano on the periphary of the household . She tries her best to hold the unity of the family but fails when her own husband informs her that she has to go with someone else in the last phase of her life. She has become the ‘other’ because of her gender and class. She feels alinated in this world which is full of people but none her own. The patriarchal setup of the novel does not allow a woman to lead a simple life of a wife and mother.

Miniaturized redox flow batteries have seen interest in electronic applications because of their potential to simultaneously deliver electric power and remove heat. For these applications, the flow battery has to be constructed on a side of a computer chip, with components such as flow channels, manifolds, supply tubes, electrodes, membranes and current collectors. There are efforts underway to optimize the design of these components for different objectives such as maximum power density or maximum efficiency. Due to space constraints, design rules employed for classical redox flow batteries are only of limited use in microfluidic systems. Since experimentation with micro-scale components is especially expensive and time-consuming, there is a need to develop computational tools to understand trade-offs in the design and operation of these flow batteries. Computational fluid dynamics study of redox flow batteries using vii COMSOL Multiphysics software has been done. PEM fuel cells are very similar to flow batteries. The high temperature PEM fuel cell was studied first to understand the electrochemistry involved in such systems. The anolyte and catholyte fluid flows are modeled using Navier-Stokes equations of mass and momentum conservation. Species diffusion through porous electrodes is modeled using species-dependent diffusion coefficients, which are calculated based on the fluid state and the electrode geometry. The electrochemical reactions are modeled using the Butler-Volmer equation with a pre-defined exchange current density. The species concentrations, velocities and pressures are solved in the simulation. We found that the flow channel geometry and manifold design has an important effect on the flow distribution. It also affects the pressure drop, thereby affecting the pumping power required to keep the battery operational. The effect of different operating conditions such as electrolyte flow rate and state of charge has been simulated and it has been found that these parameters has significant effect on flow battery performance. Based on these findings, we make observations regarding cell design and operation. We expect that these simulations, once validated with experiments, lead to a better understanding of the trade-offs involved in the design and operation of miniature redox flow batteries for electronic applications., by Brijesh Kumar, M.Tech.

Wetting behaviour of surfaces is believed to be affected by van der Waals (vdW) forces, however, there is no clear demonstration of this. With the isolation of two-dimensional vdW layered materials it is possible to test this hypothesis. In this paper, we report the wetting behaviour of vdW heterostructures which include, chemical vapor deposition (CVD) grown graphene, molybdenum disulfide (MoS2) and tungsten disulfide (WS2) on few layers of hexagon boron nitride (h-BN) and SiO2/Si. Our study clearly shows that while this class of two-dimensional materials are not wetting transparent, there seems to be a significant amount of influence on their wetting properties by the underlying substrate due to dominant vdW forces. Contact angle measurements indicate that graphene and graphene-like layered transitional metal dichalcogenides invariably have intrinsically dispersive surfaces with a dominating London-vdW force-mediated wettability. Electric field controlled wetting studies of MoS2/WS2/SiO2/Si heterostructures were performed and no notable changes to the water contact angle was seen with applied voltage although two orders of magnitude change in resistance was observed. We postulate that the highly dispersive nature of these surfaces arising from the predominant London-vdW forces could be the reason for such observation.

In this work tin nitride nanoparticles having controlled size have been synthesized by halide vapor phase epitaxy at atmospheric pressure. Tin nitride nanoparticles having three different sizes: 3 ± 0.5 nm, 6 ± 1.0 nm and 11 ± 1.5 nm have been synthesized simultaneously in a single batch at different substrate temperatures by placing the substrate at different distances from the source. The depositions have been carried out on gold-coated silicon substrates using SnCl4·5H2O as the precursor, NH3 as the nitrogen supplier and N2 as the carrier gas. This is the first report on the synthesis of tin nitride in nanoparticle form.

The margins of the nation displace the center; the peoples of the periphery return to rewrite the history and fiction of the metropolis?. (Homi Bhabha. 1990:6) Among the literary reviewers and critics of literature, it has always been a controversial question to fix ?What constitutes the literariness of a work of literature?? In its response, many scholars have tried to formulate various theories since the birth of literature till now. Their theories incorporate various rules, in other words literary aesthetics, which are a pre-requisite for every standard work of art and literature. In the Indian context, the classical rules of literature are found in Bharatmuni’s Natyasastra, an ancient Sanskrit text on dramaturgy, and other Brahmanic books written in Sanskrit. Since most of the books written on the above formula are religious, they can?t represent the whole of the Indian society because it is divided into Vernas which are; Brahmin, Kshatriya, Vaishya and Sudra.

We present optical photometric and spectroscopic observations of supernova 2013ej. It is one of the brightest type II supernovae exploded in a nearby ($\sim 10$ Mpc) galaxy NGC 628. The light curve characteristics are similar to type II SNe, but with a relatively shorter ($ \sim85 $ day) and steeper ($ \sim1.7 $ mag (100 d)$^{-1} $ in V) plateau phase. The SN shows a large drop of 2.4 mag in V band brightness during plateau to nebular transition. The absolute ultraviolet (UV) light curves are identical to SN 2012aw, showing a similar UV plateau trend extending up to 85 days. The radioactive $^{56}$Ni mass estimated from the tail luminosity is $ 0.02 $M$_{\odot}$ which is significantly lower than typical type IIP SNe. The characteristics of spectral features and evolution of line velocities indicate that SN 2013ej is a type II event. However, light curve characteristics and some spectroscopic features provide strong support in classifying it as a type IIL event. A detailed SYNOW modelling of spectra indicates the presence of some high velocity components in H$\alpha$ and H$\beta$ profiles, implying possible ejecta-CSM interaction. The nebular phase spectrum shows an unusual notch in the H$\alpha$ emission which may indicate bipolar distribution of $^{56}$Ni. Modelling of the bolometric light curve yields a progenitor mass of $ \sim14 $M$_{\odot}$ and a radius of $ \sim450 $R$_{\odot}$, with a total explosion energy of $ \sim2.3\times10^{51} $ erg., Comment: 19 pages, 19 figures, 6 tables. Accepted for publication in ApJ

Amaç: Çalışmamızın esas amacı hamatum kemikciğinin hamulus’unun en zayıf kısmını tespit etmek ve bu zayıf bölgenin damarsal özelliğini belirtmektir. Araçlar ve Yöntemler: Çalışmamızı Anatomi Bölümü, Manipal Üniversitesi’nden elde ettiğimiz 55 adet el kemiği üzerinde yaptık. Kemikler Güney Hindistan orijinli yetişkin kadavralara aitti. 55 kemiğin 27’si sağ, 28’i ise sol tarafa aitti. Ölçümlerimizde birim aralığı 10μm olan Elektronik Digital Kumpas kullandık. Vaskular foramen’leri görebilmek için x10 büyütmeli lens kullandık. Bulgular: Ölçüm yaptığımız tüm parametrelerde sağ ve sol hamatum kemikciğinin hamulus’ları arasında istatistiksel olarak anlamlı bir fark bulmadık (P>0,05). Hamatum kemikciğinin hamulus’larının hepsinde vaskular foramen’ler hamulus’un tabanında yer almaktaydı. 17 vakada (%30) hamulus’un uç kısmında vaskular foramen’lere rastlanmadı. Sadece 4 hamatum kemikciğinin hamulus’unda vaskular foramen’ler hamulus’un kıvrımındaydı. Sonuçlar: Hamatum kemikciğinin hamulus’larının çoğunda kıvrım yerlerinde vaskular foramen’lere rastlanmadığı için, bu bölge avaskuler nekrozlara daha yatkındır. Bu da bize hamatum kemikciği’nin en zayıf kısmının kıvrım yeri olduğunun hipotezini sunmaktadır.

A spin-1 Heisenberg model on trimerized Kagom�� lattice is studied by doing a low-energy bosonic theory in terms of plaquette-triplons defined on its triangular unit-cells. The model has an intra-triangle antiferromagnetic exchange interaction, $J$ (set to 1), and two inter-triangle couplings, $J^\prime>0$ (nearest-neighbor) and $J^{\prime\prime}$ (next-nearest-neighbor; of both signs). The triplon analysis of this model studies the stability of the trimerized singlet (TS) ground state in the $J^\prime$-$J^{\prime\prime}$ plane. It gives a quantum phase diagram that has two gapless antiferromagnetically (AF) ordered phases separated by the spin-gapped TS phase. The TS ground state is found to be stable on $J^{\prime\prime}=0$ line (the nearest-neighbor case), and on both sides of it for $J^{\prime\prime}\neq 0$, in an extended region bounded by the critical lines of transition to the gapless AF phases. The gapless phase in the negative $J^{\prime\prime}$ region has a $\sqrt{3}\times\sqrt{3}$ coplanar $120^\circ$-AF order, with all the moments of equal length and relative angles of $120^\circ$. The other AF phase, in the positive $J^{\prime\prime}$ region, is found to exhibit a different coplanar order with ordering wave vector ${\bf q}=(0,0)$. Here, two magnetic moments in a triangle are of same magnitude, but shorter than the third. While the angle between the two short moments is $120^\circ-2��$, it is $120^\circ+��$ between a short and the long one. Only when $J^{\prime\prime}=J^\prime$, their magnitudes become equal and the relative-angles $120^\circ$. This ${\bf q}=(0,0)$ phase has the translational symmetry of the Kagom�� lattice with isosceles triangular unit-cells. The ratio of the intensities of certain Bragg peaks, $I_{(1,0)}/I_{(0,1)} = 4\sin^2{(\frac��{6}+��)}$, presents an experimental measure of the deviation, $��$, from the $120^\circ$ order., 15 pages, 12 figures

The minimal effective model for the magnetisation plateaus below 1/2 in the Shastry-Sutherland model is derived to be an Ising model of certain unit-cell hard-core bosons with anisotropic repulsive interactions on isosceles triangular lattice. It unambiguously gives the prominent plateaus at 1/8, 1/6, 1/4, 1/3 and an additional one at 3/8, related through a particle-hole (p-h) transformation. The Dzyaloshinsky-Moriya (DM) interaction dresses it up with an inhomogeneous transverse field that also causes p-h asymmetry due to an in-plane component of the inter-dimer DM vector. This explains the asymmetry between the magnetisation below and above 1/4 in SrCu$_2$(BO$_3$)$_2$. The effective model above 1/2 plateau is an XXZ model with stronger XY parts. It gives no magnetisation plateaus, but exhibits chiral order., Comment: 5 pages, 10 figures

Aryabhatta Research Institute of Observational Sciences (acronym ARIES) operates a 1-m aperture optical telescope at Manora Peak, Nainital since 1972. Considering the need and potential of establishing moderate size optical telescope with spectroscopic capability at the geographical longitude of India, the ARIES plans to establish a 3.6m new technology optical telescope at a new site called Devasthal. This telescope will have instruments providing high resolution spectral and seeing-limited imaging capabilities at visible and near-infrared bands. A few other observing facilities with very specific goals are also being established. A 1.3m aperture optical telescope to monitor optically variable sources was installed at Devasthal in the year 2010 and a 0.5-m wide field (25 square degrees) Baker-Nunn Schmidt telescope to produce a digital map of the Northern sky at optical bands was installed at Manora Peak in 2011. A 4-m liquid mirror telescope for deep sky survey of transient sources is planned at Devasthal. These optical facilities with specialized back-end instruments are expected to become operational within the next few years and can be used to optical studies of a wide variety of astronomical topics including follow-up studies of sources identified in the radio region by GMRT and UV/X-ray by ASTROSAT., 6 pages, conference proceedings

We present the low-resolution spectroscopic and UBVRI broad-band photometric investigations of the Type IIb supernova 2011fu, discovered in UGC 01626. The photometric follow-up of this event has been initiated a few days after the explosion and covers a period of about 175 days. The early-phase light curve 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. Modelling of the quasi-bolometric light curve suggests that the progenitor had an extended ($\sim 1 \times 10^{13}$ cm), low-mass ($\sim 0.1$ $M_\odot$) H-rich envelope on top of a dense, compact ($\sim 2 \times 10^{11}$ cm), more massive ($\sim$ 1.1 $M_\odot$) He-rich core. The nickel mass synthesized during the explosion was found to be $\sim$ 0.21 $M_\odot$, slightly larger than seen in case of other Type IIb SNe. The spectral modelling performed with SYNOW suggests that the early-phase line velocities for H and Fe\,{\sc ii} features were $\sim 16000$ km s$^{-1}$ and $\sim 14000$ km s$^{-1}$, respectively. Then the velocities declined up to day +40 and became nearly constant at later epochs., 16 pages, 9 figures, 7 tables, accepted to MNRAS

The Large Area Telescope (LAT) onboard the {\it Fermi} Gamma Ray Space Telescope has detected ��-ray emission from some Narrow Line Seyfert 1(NLSy1) galaxies. This indicates the presence of relativistic jets in these sources similar to blazars and radio galaxies. In an attempt to have an idea of the intranight optical variability (INOV) characteristics of these ��-ray loud NLSy1 galaxies, we have carried out optical flux monitoring observations of three NLSy1 galaxies detected by {\it Fermi}/LAT: 1H 0323+342, PMN J0948+0022 and PKS 1502+036. These optical monitoring observations showed the presence of rapid optical flux variations in these sources. The intranight differential light curves of these sources have revealed flux variations on time scales of hours with amplitudes of variability > 3 percent for most of the time. On using the {\it F}-statistics to classify the variability nature of these sources, we obtained a duty cycle (DC) of INOV of ~85 percent. Alternatively, the more commonly used {\it C}-statistics gave a DC of INOV of ~57 percent. Such high DC of INOV are characteristics of the BL Lac class of AGN. The results of our monitoring observations thus indicate that there is similarity in the INOV nature of ��-ray loud NLSy1 galaxies and BL Lac objects, arguing strongly for the presence of relativistic jets aligned closely to the observers line of sight. Moreover, our dense monitoring observations on some of the nights have led to the clear detection of some mini-flares superimposed on the flux variations during the night over timescales as short as 12 minutes. The detection of short timescale flux variability in the sources studied here is clearly due to stronger time compression leading to the jets in these sources having large Doppler factors, similar to that of the inner jets of TeV blazars., 10 pages, 5 figures, to be appeared in MNRAS

We study a class of spin-1/2 quantum antiferromagnetic chains using DMRG technique. The exchange interaction in these models decreases linearly as a function of the separation between the spins, $J_{ij} = R-|i-j|$ for $|i-j| \le R$. For the separations beyond $R$, the interaction is zero. The range parameter $R$ takes positive integer values. The models corresponding to all the odd values of $R$ are known to have the same exact doubly degenerate dimer ground state as for the Majumdar-Ghosh (MG) model. In fact, R=3 is the MG model. For even $R$, the exact ground state is not known in general, except for R=2 (the Bethe ansatz solvable Heisenberg chain) and in the asymptotic limit of $R$ where the two MG dimer states again emerge as the exact ground state. In the present work, we numerically investigate the even-$R$ models whose ground state is not known analytically. In particular, for R=4, 6 and 8, we have computed a number of ground state properties. We find that, unlike R=2, the higher even-$R$ models are spin-gapped, and show strong dimer-dimer correlations of the MG type. Moreover, the spin-spin correlations decay very rapidly, albeit showing weak periodic revivals., Comment: 8 pages, 12 figures

We present results of a variability search in the intermediate-age open cluster NGC 6866 from 29 nights over two observing seasons. We find 28 periodic variables, of which 19 are newly identified. The periods of these variables, which have V magnitudes from 11.5 to 19.3 mag, range from ~ 48 min to 37 d. We detected several delta-Scuti stars, some of which are of high amplitude, as well as gamma-Doradus, rotational variables and eclipsing binaries. In order to study the physical properties of the cluster, we obtained UBVRI photometry of all the stars on a good photometric night. The radial distribution of the stellar surface density shows that the cluster has a radial extent of about 7 arcmin (~3 pc) with a peak density of 5.7+/-0.7 stars/arcmin^2 at the cluster center. The colour-colour diagram indicates a reddening of E(B-V) = 0.10 mag towards NGC 6866. A distance of ~ 1.47 kpc and an age of ~ 630 Myr is estimated from the colour-magnitude diagram using the theoretical isochrones of solar metallicity., accepted for publication in MNRAS

We present BV RI photometric and low-resolution spectroscopic investigation of a type II core-collapse supernova (SN) 2008gz, which occurred in a star forming arm and within a half-light radius (solar metallicity region) of a nearby spiral galaxy NGC 3672. The SN event was detected late and a detailed investigation of its light curves and spectra spanning 200 days suggest that it is an event of type IIP similar to archetypal SNe 2004et and 1999em. However, in contrast to other events of its class, the SN 2008gz exhibits rarely observed V magnitude drop of 1.5 over the period of a month during plateau to nebular phase. Using 0.21 mag of Av as a lower limit and a distance of 25.5 Mpc, we estimate synthesized $^{56}$Ni mass of 0.05 \pm 0.01 M* and a mid-plateau Mv of -16.6 \pm 0.2 mag. The photospheric velocity is observed to be higher than that was observed for SN 2004et at similar epochs, indicating explosion energy was comparable to or higher than SN 2004et. Similar trend was also seen for the expansion velocity of H-envelopes. By comparing its properties with other well studied events as well as by using a recent simulation of pre-SN models of Dessart, Livne & Waldman (2010), we infer an explosion energy range of 2 - 3 x 10$^{51}$ erg and this coupled with the observed width of the forbidden [O I] 6300-6364 {\AA} line at 275 days after the explosion gives an upper limit for the main-sequence (non-rotating, solar metallicity) progenitor mass of 17 M*. Our narrow-band H{\alpha} observation, taken nearly 560 days after the explosion and the presence of an emission kink at zero velocity in the Doppler corrected spectra of SN indicate that the event took place in a low luminosity star forming H II region., Comment: Accepted for publication in MNRAS

Precise control of morphologies of one-dimensional (1D) or 2D nanostructures during growth has not been easily accessible, usually degrading the device performance and therefore limiting applications to various advanced nanoscale electronics and optoelectronics. Graphene could be a platform to serve as a substrate for both morphology control and direct use of electrodes due to its ideal monolayer flatness with {\pi} electrons. Here, we report that by using graphene directly as a substrate, vertically well-aligned ZnO nanowires and nanowalls were obtained systematically by controlling Au catalyst thickness and growth time, without invoking significant thermal damage on the graphene layer during thermal chemical vapor deposition of ZnO at high temperature of about 900 oC. We further demonstrate a piezoelectric nanogenerator that was fabricated from the vertically aligned nanowire-nanowall ZnO hybrid/graphene structure generates a new type of direct current.

We present time-series photometry of stars located in the extremely young open cluster Berkeley 59. Using the 1.04 m telescope at ARIES, Nainital, we have identified 42 variables in a field of 13'x13' around the cluster. The probable members of the cluster are identified using (V, V-I) colour-magnitude diagram and (J-H, H-K) colour-colour diagram. Thirty one variables are found to be pre-main sequence stars associated with the cluster. The ages and masses of pre-main sequence stars are derived from colour-magnitude diagram by fitting theoretical models to the observed data points. The ages of the majority of the probable pre-main sequence variable candidates range from 1 to 5 Myrs. The masses of these pre-main sequence variable stars are found to be in the range of ~0.3 to ~3.5 Msun and these could be T Tauri stars. The present statistics reveal that about 90% T Tauri stars have periods < 15 days. The classical T Tauri stars are found to have larger amplitude in comparison to the weak line T Tauri stars. There is an indication that the amplitude decreases with increase of the mass, which could be due to the dispersal of disk of relatively massive stars., 11 pages, 12 Figures and 2 tables, Accepted for publication in MNRAS

We present X-ray analysis of two Wolf-Rayet (WR) binaries: V444 Cyg and CD Cru using the data from observations with XMM-Newton. The X-ray light curves show the phase locked variability in both binaries, where the flux increased by a factor of $\sim 2$ in the case of V444 Cyg and $\sim 1.5$ in the case of CD Cru from minimum to maximum. The maximum luminosities in the 0.3--7.5 keV energy band were found to be $5.8\times10^{32}$ and $2.8\times10^{32}$ erg s$^{-1}$ for V444 Cyg and CD Cru, respectively. X-ray spectra of these stars confirmed large extinction and revealed hot plasma with prominent emission line features of highly ionized Ne, Mg, Si, S, Ar, Ca and Fe, and are found to be consistent with a two-temperature plasma model. The cooler plasma at a temperature of $\sim$ 0.6 keV was found to be constant at all phases of both binaries, and could be due to a distribution of small-scale shocks in radiation-driven outflows. The hot components in these binaries were found to be phase dependent. They varied from 1.85 to 9.61 keV for V444 Cyg and from 1.63 to 4.27 keV for CD Cru. The absorption of the hard component varied with orbital phase and found to be maximum during primary eclipse of V444 Cyg. The high plasma temperature and variability with orbital phase suggest that the hard-component emission is caused by a colliding wind shock between the binary components., Comment: 15 pages, 8 figures, 5 tables. accepted for publication in MNRAS

We present UBVRI CCD photometry in the region of the open clusters NGC 637 and NGC 957. The radii are found to be 4.2 arcmin and 4.3 arcmin. Their reddenings E(B-V) are 0.64+/-0.05 mag and 0.71+/-0.05 mag and their distances, from main sequence fitting are 2.5+/-0.2 kpc and 2.2+/-0.2 kpc. Comparison with Z=0.02 isochrones leads to an age of 10+/-5 Myr for both clusters. Combining our photometry with 2MASS JHK shows the reddening law in these directions to be normal. Mass function slopes of x=1.65+/-0.20 and 1.31+/-0.50 are derived for the clusters, both of which are found to be dynamically relaxed. Spectral and photometric characteristics of three Be stars, two in NGC 957 and one (newly discovered) in NGC 637 indicate them to be of Classical Be type., Comment: Accepted for publication in MNRAS

We study the competition between antiferromagnetic order and valence bond solid formation in a two-dimensional frustrated spin-1/2 model. The J1-J2 model on the square lattice is further frustrated by introducing products of three-spin projectors which stabilize four dimer-product states as degenerate ground states. These four states are reminiscent of the dimerized singlet ground state of the Shastry-Sutherland model. Using exact diagonalizations, we study the evolution of the ground state by varying theratio of interactions. For a large range of parameters (J2 > 0.25J1), our model shows a direct transition between the valence-bond-solid phase and the collinear antiferromagnetic phase. For small values of J2, several intermediate phases appear which are also analyzed.

Two quantum spin models with bilinear-biquadratic exchange interactions are constructed on the checkerboard lattice. It is proved that, under certain sufficient conditions on the exchange parameters, their ground states consist of two degenerate Shastry-Sutherland singlet configurations. The constructions are studied for arbitrary spin-S. The sufficient conditions for the existence of ferromagnetic ground state are also found exactly. The approximate quantum phase diagrams are presented using the exact results, together with a variational estimate for the N\'eel antiferromagnetic phase. A two-leg spin-1/2 ladder model, based on one of the above constructions, is considered which admits exact solution for a large number of eigenstates. The ladder model is shown to have exact level-crossing between the rung-singlet state and the AKLT state in the singlet ground state. Also introduced is the notion of perpendicularity for quantum spin vectors, which appears in the discussion on one of the two checkerboard models, and is discussed in the Appendix., Comment: Revtex, 10 pages, 6 figures, 3 tables

Motivated by the recent discovery of superconductivity in two-dimensional $CoO_2$ layers, we present some possibly useful results of the resonating valence bond mean-field theory applied to the triangular lattice. An interesting time reversal breaking superconducting state arises from strongly frustrated interactions. Away from half filling, the order parameter is found to be complex, and yields a fully gapped quasiparticle spectrum. The sign of the hopping plays a crucial role in the analysis, and we find that superconductivity is as fragile for one sign as it is robust for the other. $Na_xCoO_2 \cdot yH_2O$ is argued to belong to the robust case, by comparing the local-density approximation fermi surface with an effective tight-binding model. The high-frequency Hall constant in this system is potentially interesting, since it is pointed out to increase linearly with temperature without saturation for T>Tdegeneracy.