Probing protein-protein interactions by dynamic force correlated spectroscopy (FCS)

We develop a formalism for single molecule dynamic force spectroscopy to map the energy landscape of protein-protein complex ($P_1$$P_2$). The joint distribution $P(\tau_1,\tau_2)$ of unbinding lifetimes $\tau_1$ and $\tau_2$ measurable in a compression-tension cycle, which accounts for the internal relaxation dynamics of the proteins under tension, shows that the histogram of $\tau_1$ is not Poissonian. The theory is applied to the forced unbinding of protein $P_1$, modeled as a wormlike chain, from $P_1$$P_2$. We propose a new class of experiments which can resolve the effect of internal protein dynamics on the unbinding lifetimes.Comment: 12 pages, 3 figures, accepted to Phys. Rev. Let

Studies on the seasonal incidence of sugarcane internode borer, Chilo saccariphagus indicus (kapur) in Tamil Nadu, India

Internode borer (INB), Chilo saccariphagus indicus (Kapur) (Lepidoptera: Pyraustidae) is an important pest on sugarcane which inflicts yield loss of about than 45 per cent. Pest surveillance and forecasting is one of the important prerequisite tools in managing such pests. Hence, an attempt was made to study the seasonal incidence of the INB during 2007 and 2008 at Nellikuppam, Tamil Nadu, India. The study revealed that the peak incidence of INB was observed during June-July, which declined thereafter. Higher temperature and deficit or failure of rainfall during March –May are considered as the favourable factors for the rise in the incidence of INB

Magnetic field stabilization system for atomic physics experiments

Atomic physics experiments commonly use millitesla-scale magnetic fields to provide a quantization axis. As atomic transition frequencies depend on the amplitude of this field, many experiments require a stable absolute field. Most setups use electromagnets, which require a power supply stability not usually met by commercially available units. We demonstrate stabilization of a field of 14.6 mT to 4.3 nT rms noise (0.29 ppm), compared to noise of $\gtrsim$ 100 nT without any stabilization. The rms noise is measured using a field-dependent hyperfine transition in a single $^{43}$Ca$^+$ ion held in a Paul trap at the centre of the magnetic field coils. For the $^{43}$Ca$^+$ "atomic clock" qubit transition at 14.6 mT, which depends on the field only in second order, this would yield a projected coherence time of many hours. Our system consists of a feedback loop and a feedforward circuit that control the current through the field coils and could easily be adapted to other field amplitudes, making it suitable for other applications such as neutral atom traps.Comment: 6 pages, 5 figure

Image Coding of 3D Volume Using Wavelet Transform for Fast Retrieval of 2D Images

An encoder/decoder system for 3D volumetric medical data is proposed. The system allows fast access to any 2D image by decoding only the relevant information from each subband image and thus provides minimum decoding time. This will be of immense use for the medical community because most of the computerised tomography, magnetic resonance imaging and positron emission tomography modalities produce volumetric data. As a fully fledged 3D wavelet transform is used for compression, the advantage of good compression ratio is preserved. Preprocessing is carried out prior to wavelet transform, to enable easier identification of coefficients from each subband image. Inclusion of special characters in the bit stream (markers) facilitates access to corresponding information from the encoded data. Experiments are carried out by performing Daub4 filter along x (row) and y (column) directions and Haar filter along the z (slice) direction to account for the difference between interslice and intraslice resolution. The performance of the system has been evaluated on four sets of volumetric data and the results are compared to other 3D encoding/2D decoding schemes. Results show that for slice spacing of 3–10 mm, there is substantial improvement in decoding time. The speedup is found to be 2

Prevalence of menstrual morbidity in adolescents girls: a cross sectional study

Background: Menstruation is said to be a physiological process in women. The word ‘menstruation’ was derived from a Latin word ‘menses’. Menstrual dysfunction was found to affect 75% of adolescent girls which includes dysmenorrhoea, menorrhagia and irregular cycles. Premenstrual syndrome constitutes a group of physical and emotional symptoms which occurs one week before menstrual cycle. It was found to be a cycle disorder which appears in the luteal phase. Adolescent girls are at high risk of developing premenstrual syndrome. Because of menstrual dysfunction and premenstrual syndrome, the adolescent girls are at high risk of menstrual morbidity.Methods: After getting approval from institutional ethical committee of Madras Medical College, the study was carried out in adolescent girls. The study was carried out by giving questionnaire in nearly 505 students for the duration of 6 months. The study participants were explained about the study. The questionnaire was structured so as to obtain information regarding the age at menarche, duration of cycle, awareness about menstruation, source of information regarding menstruation, practices during menstrual cycles, regarding menstrual problems and treatment practices.Results: The average age of participants was 17 years with an SD of 1.5. of 505 participants, about 6% had 45 days frequency, 10% had 38 days frequency and 2% had 60 days frequency of menstrual cycle. It was found around 1% had 8 days duration and 3% had 9 days duration of menstrual cycle. About 13% of Participants had mild flow, 7% had severe flow and 20% had variable quantity of menstrual flow.Conclusions: From this study, it was found that menstrual dysfunction were prevalent among adolescent girls. These were found to cause menstrual morbidity among adolescent girls. Hence it is necessary to educate and create awareness about menstrual morbidity among adolescent girls.

Relaxational behavior of the infinite-range Ising spin-glass in a transverse field

We study the zero-temperature behavior of the infinite-ranged Ising spin glass in a transverse field. Using spin summation techniques and Monte Carlo methods we characterize the zero-temperature quantum transition. Our results are well compatible with a value $\nu=\frac{1}{4}$ for the correlation length exponent, $z=4$ for the dynamical exponent and an algebraic decay $t^{-1}$ for the imaginary-time correlation function. The zero-temperature relaxation of the energy in the presence of the transverse field shows that the system monotonically reaches the ground state energy due to tunneling processes and displays strong glassy effects.Comment: 15 pages + 5 Figures, Revte

Distributed coding of multiresolution omnidirectional images

This paper addresses the problem of compact representation of a 3D scene, captured by distributed omnidirectional cameras. As the images from the sensors are likely to be correlated in most practical scenarios, we build a distributed algorithm based on coding with side information. A reference image is processed with a wavelet transform and progressively encoded. The Wyner-Ziv images undergo a multiresolution representation, and the generated bitplanes are channel encoded with LDPC codes. The central decoder eventually reconstructs the Wyner-Ziv images given by the syndrome bits from the channel codes using the reference omnidirectional image. It also iteratively implements motion estimation on the 2-sphere in order to improve the side information. Experimental results demonstrate that distributed coding improves the rate-distortion performance for coding a set of omnidirectional images when compared to independent coding solutions. The proposed method can further be extended to the decoding of multiple Wyner-Ziv images using one single reference omnidirectional image. Hence, it achieves a reduced overall coding rate compared to disparity-based schemes. In addition, it does not require explicit knowledge of the camera parameters nor precise calibration, which is certainly interesting in camera networks

Balanced Distributed Coding of Omnidirectional Images

This paper presents a distributed coding scheme for the representation of 3D scenes captured by a network of omnidirectional cameras. We consider a scenario where images captured at different viewpoints are encoded independently, with a balanced rate distribution among the different cameras. The distributed coding is built on multiresolution representation and partitioning of the visual information in each camera. The encoder then transmits one partition after entropy coding, as well as the syndrome bits resulting from the channel encoding of the other partition. The joint decoder exploits the intra-view correlation by predicting the missing source information with help of the syndrome bits. At the same time, it exploits the inter-view correlation by using motion estimation between images from different cameras. Experiments demonstrate that the distributed coding solution performs better than a scheme where images are handled independently, while the coding rate advantageously stays balanced between encoders

STUDIES ON GENETIC DIVERSITY IN Vigna mungo L. Hepper IN YMV HOTSPOT

            The present investigation was conducted to examine the 41 blackgram genotypes  along with one check (T-9) to study the genetic diversity. Analysis of variance showed highly significant differences among 41blackgram genotypes for 9 quantitative characters studied. Maximum genotypic and phenotypic variance was recorded for percentage of disease infection, single plant seed yield, and number of pods per plant.   Minimum   GCV and PCV were recorded for pod length, days to 50% flowering, number of seeds per pod. High heritability was recorded for percentage of disease infection, single plant seed yield, and number of pods per plant. High heritability coupled with high genetic advance as percent of mean was recorded for percentage of disease infection, single plant seed yield. Genetic diversity estimated in 41 blackgram genotypes using Mahalanobis’s D2 statistic. Forty one genotypes were grouped into seven clusters by Tocher method (Mahalanobis Euclidean Distance) cluster analysis.  The  maximum  inter-cluster  distance  was  observed  between  cluster VI  and  cluster  VII and maximum intra-cluster distance was observed in cluster VI.  Cluster VII showed maximum cluster mean value for seed yield per plant. Among all the characters, seed yield per plant and percentage of disease infection contributes maximum