Low-frequency phase diagram of irradiated graphene and periodically driven spin-1/2 XYXY chain

We study the Floquet phase diagram of two-dimensional Dirac materials such as graphene and the one-dimensional (1D) spin-1/2 $XY$ model in a transverse field in the presence of periodic time-varying terms in their Hamiltonians in the low drive frequency ($\omega$) regime where standard $1/\omega$ perturbative expansions fail. For graphene, such periodic time dependent terms are generated via the application of external radiation of amplitude $A_0$ and time period $T = 2\pi/\omega$, while for the 1D $XY$ model, they result from a two-rate drive protocol with time-dependent magnetic field and nearest-neighbor couplings between the spins. Using the adiabatic-impulse method, we provide several semi-analytic criteria for the occurrence of changes in the topology of the phase bands of such systems. For irradiated graphene, we point out the role of the symmetries of $H(t)$ and $U$ behind such topology changes. Our analysis reveals that at low frequencies, phase band topology changes may also happen at $t= T/3, 2T/3$ (apart from $t=T$). We chart out the phase diagrams at $t=T/3, 2T/3,\, {\rm and }\, T$ as a function of $A_0$ and $T$ using exact numerics, and compare them with the prediction of the adiabatic-impulse method. We show that several characteristics of these phase diagrams can be analytically understood from results obtained using the adiabatic-impulse method and point out the crucial contribution of the high-symmetry points in the graphene Brillouin zone to these diagrams. Finally we study the 1D $XY$ model with a two-rate driving protocol using the adiabatic-impulse method and exact numerics revealing a phase band crossing at $t=T/2$ and $k=\pi/2$. We also study the anomalous end modes generated by such a drive. We suggest experiments to test our theory.Comment: v1; 26 pages, 19 Fig

LIS journals in India: Current status and some improvement measures

The paper identifies the present status of journal publishing in India in the field of library & information science. Identification of journals were made by consulting various sources. The characteristics of the journals have been studied on various parameters like number of years of existence, type of publisher, accessibility, references and citation characteristics, etc. Of the total 72 identified journals, it was observed that almost 70% journals started their publication from 2000 onwards. About 81% journals are available on subscription basis. Print as well as online format for dissemination of research have been adopted by 59% journals, however, 30% journals are still available only in print form. It is seen that private or profit-making (59%) organizations are more interested to publish LIS journals than non-profit making organizations (41%). One of the major drawbacks of Indian LIS journals is there poor visibility and limited coverage in various bibliographical databases. More than 54% journals are not indexed in any important bibliographic database and only 6 journals are indexed in LISA, LISTA or ILSA. The citation statistics of these journals are not satisfactory as 42 journals did not receive any citations for their articles published during 2011-2013. At the end, the study suggests a few measures for improving the quality of journal in LIS domai

Menstrual Characteristics of Adolescent Athletes: A Study from West Bengal, India

The present study investigates: (i) differences in menstrual characteristics of athlete and non-athlete adolescents; (ii) relationship between menstrual characteristics, anthropometric variables, athletic status and socioeconomic status. The present study was conducted among 159 unmarried adolescents (80 athletes and 79 non-athletes) of age 15 to 19 years. The study participants belong to Bengali speaking Hindu ethnic group of Kolkata, the capital city of West Bengal State of India. Data were collected on socio-demographic and menstrual characteristics using pre-tested questionnaires. Anthropometric measurements were taken following standard methods. Descriptive statistics were used to understand the differences in menstrual characteristics between athletes and non-athletes, stepwise linear regression analyses were carried out to predict age at menarche, menstrual cycle length and duration of menstrual discharge using socio-demographic and anthropometric variables as well as athletic status as independent variables. Logistic (binary) regression was carried out to assess the strength of association between menstrual characteristics (as dependent variables) and athletic status, socio-demographic and anthropometric variables, and other menstrual characteristics (independent variables). The study participants differ significantly (p≤0.05) for certain menstrual characteristics such as age at menarche, cycle length, skipped cycle, premenstrual syndrome, heavy discharge when compared for their athletic status. Certain anthropometric and socioeconomic variables were found to be significantly associated with their menstrual characteristics. The study results demonstrate that menstrual functioning among adolescents is significantly influenced by their athletic status. The findings of this study would help health care professionals to devise future health care programs for adolescents in general and athletes in particular

Menstrual Characteristics of Adolescent Athletes: A Study from West Bengal, India

The present study investigates: (i) differences in menstrual characteristics of athlete and non-athlete adolescents; (ii) relationship between menstrual characteristics, anthropometric variables, athletic status and socioeconomic status. The present study was conducted among 159 unmarried adolescents (80 athletes and 79 non-athletes) of age 15 to 19 years. The study participants belong to Bengali speaking Hindu ethnic group of Kolkata, the capital city of West Bengal State of India. Data were collected on socio-demographic and menstrual characteristics using pre-tested questionnaires. Anthropometric measurements were taken following standard methods. Descriptive statistics were used to understand the differences in menstrual characteristics between athletes and non-athletes, stepwise linear regression analyses were carried out to predict age at menarche, menstrual cycle length and duration of menstrual discharge using socio-demographic and anthropometric variables as well as athletic status as independent variables. Logistic (binary) regression was carried out to assess the strength of association between menstrual characteristics (as dependent variables) and athletic status, socio-demographic and anthropometric variables, and other menstrual characteristics (independent variables). The study participants differ significantly (p≤0.05) for certain menstrual characteristics such as age at menarche, cycle length, skipped cycle, premenstrual syndrome, heavy discharge when compared for their athletic status. Certain anthropometric and socioeconomic variables were found to be significantly associated with their menstrual characteristics. The study results demonstrate that menstrual functioning among adolescents is significantly influenced by their athletic status. The findings of this study would help health care professionals to devise future health care programs for adolescents in general and athletes in particular

Role of cervicovaginal β-hCG in prediction of preterm delivery: a prospective observational study

Background: The World Health Organization (WHO) factsheet revealed that 15 million babies are born too early every year and almost 1 million children die each year due to complications of preterm birth. The objective of this study was to determine whether cervicovaginal β-hCG level can be used as predictor of preterm delivery in asymptomatic high-risk pregnant women at 24-34 weeks gestation age.Methods: This was prospective observational study. Total 134 asymptomatic pregnant women were taken for study who had at least one risk factor for preterm delivery at 24-34 weeks gestation age. Cervicovaginal secretion was collected and β-hCG level was measured by chemiluminescent immunoassay.Results: Out of 134 cases, 42.5% had preterm delivery and 57.5% had term delivery. Mean cervicovaginal β-hCG level (mIU/ml) in preterm delivery group was 39.38±19.66 and term delivery group was 21.86±11.18. Cervicovaginal β-hCG level was significantly higher in preterm group compare to term group demonstrating significant association of raised β-hCG with preterm group (p value <0.001). ROC curve analysis was done to find out best cut off value of cervicovaginal β-hCG for prediction of preterm delivery and optimal cut off value was 36.45 mIU/ml. The optimal cut off value for cervicovaginal β-hCG (36.45 mIU/ml) gave sensitivity 71.9%, specificity 81.8%, positive predictive value 74.5%, negative predictive value 79.7% and diagnostic accuracy of 77.6% for prediction of preterm delivery.Conclusions: Cervicovaginal β-hCG can be used as sensitive and specific biomarker of prediction of preterm delivery in asymptomatic high-risk women

Kinetic Insight on Improved Chemi-Resistive Response of Hydrothermal Synthesized Pt Loaded TiO2 Nano-rods Toward Vapor Phase Isopropanol

Flower like microstructure composed of eccentrically grown vertically aligned titania nano-rods is prepared through spherical carbon template mediated hydrothermal route. Mechanistic pathways for the growth of said esthetic architecture is proposed by studying their phase formation behavior and morphological features. Chemi-resistive type sensing properties of prepared titania flowers for the detection of isopropanol are studied by varying the sensor operating temperature (225–300°C) and vapor concentration (10–200 ppm). Distinguishable sensitivity of titania flowers is identified for the detection of even 10 ppm isopropanol. Catalytic amount of Pt nano-particles (synthesized through chemical method) are introduced over prepared flower like titania to improve further their sensitivity. The plausible isopropanol sensing mechanism over TiO2 flowers as well as influence of operating temperature and role of Pt nanoparticles as chemical sensitizer in enhancing the response is explained. The current response transients of both the TiO2 flowers and their Pt modified counterpart for detecting low concentration (10–50 ppm) of isopropanol are modeled in accordance to Langmuir-Hinshelwood reaction mechanism and the rate constants for the respective surface reactions are estimated. The higher rate constant for the interaction of isopropanol over titania flowers than Pt modified counterparts is explained using the concept of decaying depleted layer during sensing

Agonistic Association of Lepidoptera and Fungus in the Development of Leaf-spot Disease in High Altitude Mango and its Control

Plants are common prey for pests, though plants at high altitudes are less prone to diseases. However, our sample proved to be an exception, as disease in plants have become a major problem in North India, especially in old, crowded orchards where there is excessive shade .Mango, our test plant, is well adapted to tropical and subtropical climate. Here we considered the mechanism of disease initiation in the mango leaves by the entry of a fungal pathogen- Cercospora mangiferae, and its possible agonistic association with an insect of the Lepidoptera group, Procontarinia sp . Our aim is to suggest a pesticide to avert the entry and reduce the occurrence of the disease. The specimen, collected from a place called Jorolle (NH 88) near Sundernagar, is 10 kms away from the Beas-Sutlej confluence in the state of Himachal Pradesh, during the months of January-February, the temperature recorded was between 7-14°C. The environment in the vicinity of the mango orchard was dry, windy, and grimy and plagued by vehicular emissions. There were predominantly 2 kinds of leaf spots-a white and a brown spot. The spread of the disease started from the lower mature leaves to the upper younger leaves. Enormity of the infection was much greater in leaves having galls along their margins. The gall formation results due to the mechanical damage caused by the infection due to a midge fly (Procontarinia sp). The average diameter of galls ranged between 3-4mm. As affirmed earlier, the leaves with large number of galls are the primary  home for the fungus- Cercospora mangiferae where they reside in larger numbers. Although the mechanism of an agonistic association is obscure but the possibility of such an association cannot be ruled out completely; where the primary infection caused by the midge insect paves the way for secondary infection by the fungus. Our sole intention was to prevent occurrence of such an association, by inhibiting both the infections from occurring individually. Our test pesticide belonged to the Malathione group. Its main component is monocrotophos which interferes not only with the nerve impulse transmission of the insect but also damages the cell wall of the fungal pathogen thereby attending both the problems. The experiment was performed with different concentrations of pesticide and it was observed that at 43.5%w/w it was effective enough to prevent 100% germination. Our studies provide a conclusive result which suggests that if the pesticide, at the effective concentration is sprayed till run-off, the young tender leaves of Mangifera indica will be protected from both the midge insect as well as the fungal pathogen.Key words: Chausa, Langra, Dashehari, Leaf spot, Cercospora mangiferae, White spot, Brown Spot, Gall, Procontarinia sp., pesticide, Malathione, Hilcron, Monocrotophos Arup Kumar Mitra et al. Agonistic Association of Lepidoptera and Fungus in the Development of Leaf-spot Disease in High Altitude Mango and its Control.  J Phytol 2/7 (2010) 28-36