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

Infinite randomness and quantum Griffiths effects in a classical system: the randomly layered Heisenberg magnet

We investigate the phase transition in a three-dimensional classical Heisenberg magnet with planar defects, i.e., disorder perfectly correlated in two dimensions. By applying a strong-disorder renormalization group, we show that the critical point has exotic infinite-randomness character. It is accompanied by strong power-law Griffiths singularities. We compute various thermodynamic observables paying particular attention to finite-size effects relevant for an experimental verification of our theory. We also study the critical dynamics within a Langevin equation approach and find it extremely slow. At the critical point, the autocorrelation function decays only logarithmically with time while it follows a nonuniversal power-law in the Griffiths phase.Comment: 10 pages, 2 eps figures included, final version as published

Effect of purified alkaline phosphatase from Bacillus licheniformis on growth of Zea mays L.

Some soil microbes have the capability to solubilize mineral phosphate into organic phosphorous and used as biofertilizer to improve crop productivity in agricultural field. In this study, phosphate solubilization assay was carried out onto media plates containing calcium phsophate precipitated nutrient agar media for bacterial strains like Bacillus megaterium MTCC 453, Bacillus subtilis MTCC 1134, Bacillus licheniformis MTCC 2312, Pseudomonas aeruginosa MTCC 424, Escherichia coli MTCC 570. Among these bacterial strains, B. licheniformis MTCC 2312 showed largest clear zone of phosphate solubilzation and maximum activity of alkaline phosphatase. The enzyme alkaline phosphatase was purified from B. licheniformis MTCC 2312 with purification fold 3.52 and specific activity 295.89 Unit/mg protein using DEAE-sepharose chromatography. This enzyme showed molecular weight as 60 KD, thermostability upto 50?C, pH stability up to 8.5 and Michaelis constant (Km) and maximum activity (Vmax) as 2.30 mM and 2223 U/ml respectively. The lyophilized powder of this enzyme was further supplemented with media components for the growth of Zea mays for carrying tissue culture experiment. The sterilized soil supplemented with alkaline phosphatase improved the total height, dry weight, % phosphate content in the stem and root of Zea mays by 3.07, 3.15, 2.35 and 1.76 fold respectively compared to control set. This enzyme could be used at large extent as effective biofertilizer for the agricultural industry

Comparative study of papanicolaou smear and colposcopy in the evaluation of cervical lesions

Background: Cervical cancer is the third most common type of cancer among females. Study aims to critically evaluate the sensitivity and specificity of colposcopy versus papanicolaou (Pap) smear in the early detection of dysplasias. Its secondary objective to correlate the findings in the evaluation of unhealthy cervix by cytology, colposcopy and colposcopy guided biopsy.Methods: This was a tertiary care teaching hospital based, prospective, cross sectional study done in Department of Obstetrics and Gynaecology, at Vydehi Institute of Medical Sciences and Research Centre, Bangalore, conducted on 200 women attending Gynaecology OPD.Results: PAP smear was taken for all 200 patients. 73% of smear was found to be normal, 11% showed inflammatory atypia, 9% showed low grade squamous intraepithelial lesion (LSIL), 3.5% showed atypical squamous cells of undetermined significance (ASCUS) and 3.5% showed High Grade Squamous Intraepithelial Lesion (HSIL). Among the 200 cases studied, 38% (76/200) were diagnosed as colposcopically abnormal. Among the abnormal cases, AW areas were diagnosed in 4%. Punctate pattern of vessels was seen in 5% of women. Normal findings was present in 62%, Erosion cervix in 6%, inflammatory changes were seen in 6% and polyps were diagnosed in 7.5%, leucoplakia was found in 2% and unsatisfactory colposcopy finding was seen in 4% and underwent endocervical curettage. 32 cases out of 200 women were positive on Pap smear. 66 out of 200 women were positive on Biopsy. Pap smear was positive in 22 out of 66 biopsy proven positive cases.Conclusions: The commonest presenting complaint was vaginal discharge (182/200; 91% of the patients. the PAP smear  is found to have sensitivity of 33.33%  and specificity of 92.54%. colposcopy is found to have sensitivity of 81.82%  and specificity of 82.84%

Kisspeptin: new biomarker of pregnancy

Background: The recently identified hormone kisspeptin has been suggested to play an important regulatory role in placentation. The aim and objective of the study is the measurement of serum kisspeptin level in asymptomatic pregnant women and to find out the association of serum kisspeptin with gestational age in women with early pregnancy.Methods: This was a longitudinal study to the evaluation of 178 asymptomatic pregnant women with a gestation of 6 to 16 weeks attending routine antenatal booking visit recruited as study participants from the Antenatal Clinical of Obstetrics and Gynaecology Department, S.M.S. Medical College and Attached Hospitals, Jaipur, Rajasthan, India.Results: After initial clinical examination of every participant, a single blood sample was taken for the measurement of serum kisspeptin. Serum kisspeptin measurement test was performed by ELISA method and results were expressed as ng/ml. Pregnancy outcome was recorded prospectively. Mean serum kisspeptin level of study participants was 2.80±1.87ng/ml and median were 2.41 (Range 0.244-14.06ng/ml). Our result showed the relationship of serum kisspeptin with gestational age (GA) (p<0.000).Conclusions: serum kisspeptin level increases in pregnancy and showed positive relationship with gestational age significantly (p<0.000)

Experimental Study of Growth Parameters of Phycomyces blakesleeanus During Phototropic and Avoidance Responses

Phycomyces blakesleeanus depicts helical growth during steady state as well as under the influence of stimuli in the form of light, barrier, wind, etc. Previously, researchers have studied helical growth of Phycomyces under steady state growth and light response, however no attempts have been made to study the elongation rate, rotation rate and bend rate during phototropic and avoidance responses. The research conducted here involves experimentally determining growth parameters that occur as a response to applied stimuli. The elongation rate as well as rotation rate seem to have increased after the application of stimulus. This increase in elongation and rotation rates is hypothesized to be the influx of a biomolecule to the region of the growth zone that is subjected to the stimulus resulting in breakage of load bearing bonds on the cell wall. Through this research one can better explain cell wall expansion models and account for expansion as a result of stimuli.</p