Ferromagnetism and the Effect of Free Charge Carriers on Electric Polarization in Y_2NiMnO_6 Double Perovskite

The double perovskite Y_2NiMnO_6 displays ferromagnetic transition at Tc = 81 K. The ferromagnetic order at low temperature is confirmed by the saturation value of magnetization (M_s) and also, validated by the refined ordered magnetic moment values extracted from neutron powder diffraction data at 10 K. This way, the dominant Mn4+ and Ni2+ cationic ordering is confirmed. The cation-ordered P 21/n nuclear structure is revealed by neutron powder diffraction studies at 300 and 10 K. Analysis of frequency dependent dielectric constant and equivalent circuit analysis of impedance data takes into account the bulk contribution to total dielectric constant. This reveals an anomaly which coincides with the ferromagnetic transition temperature (T_c). Pyrocurrent measurements register a current flow with onset near Tc and a peak at 57 K that shifts with temperature ramp rate. The extrinsic nature of the observed pyrocurrent is established by employing a special protocol measurement. It is realized that the origin is due to re-orientation of electric dipoles created by the free charge carriers and not by spontaneous electric polarization at variance with recently reported magnetism-driven ferroelectricity in this materialComment: Published in Physical Review

The hidden mystery of a lustrous pearl unraveled The Hindu dated 19th October 2012

People believe that pearl is conceived by oyster when it receives a drop of rain or dew. Natural pearls form under a set of accidental conditions when a microscopic intruder or grain of sand enters an oyster (mollusk) and settles inside the shell. The oyster, being irritated by the intruder, secretes a substance called nacre to soothe its irritation. This process is repeated for many years, thus producing a real pearl which may or may not be found by man. For a natural pearl forming with a nice round or oval shape, and free of any flaws, is actually a real-life “miracle.” The chances of a perfect natural pearl are one in a million. Nacre is a combination of crystalline and organic substances

Genetic Algorithms for Cross-Calibration of Categorical Data

The probabilistic problem of cross-calibration of two categorical variables is addressed. A probabilistic forecast of the categorical variables is obtained based on a sample of observed data. This forecast is the output of a genetic algorithm based approach, which makes no assumption on the type of relationship between the two variables and applies a scoring rule to assess the fitness of the chromosomes. It converges to a good-quality point probability forecast of the joint distribution of the two variables. The proposed approach is applied both at stationary points in time and across time. Its performance is enhanced when additional sampled data is included, and can be designed with different scoring rules or made to account for missing data

Dynamic localization of SMC5/6 complex proteins during mammalian meiosis and mitosis suggests functions in distinct chromosome processes

et al.Four members of the structural maintenance of chromosome (SMC) protein family have essential functions in chromosome condensation (SMC2/4) and sister-chromatid cohesion (SMC1/3). The SMC5/6 complex has been implicated in chromosome replication, DNA repair and chromosome segregation in somatic cells, but its possible functions during mammalian meiosis are unknown. Here, we show in mouse spermatocytes that SMC5 and SMC6 are located at the central region of the synaptonemal complex from zygotene until diplotene. During late diplotene both proteins load to the chromocenters, where they colocalize with DNA Topoisomerase IIα, and then accumulate at the inner domain of the centromeres during the first and second meiotic divisions. Interestingly, SMC6 and DNA Topoisomerase IIα colocalize at stretched strands that join kinetochores during the metaphase II to anaphase II transition, and both are observed on stretched lagging chromosomes at anaphase II following treatment with Etoposide. During mitosis, SMC6 and DNA Topoisomerase IIα colocalize at the centromeres and chromatid axes. Our results are consistent with the participation of SMC5 and SMC6 in homologous chromosome synapsis during prophase I, chromosome and centromere structure during meiosis I and mitosis and, with DNA Topoisomerase IIα, in regulating centromere cohesion during meiosis II.This work was supported by Ministerio de Economía y Competitividad (Spain) [grant number SAF2011-28842-C02-01 to J.A.S. and SAF2011-25252 to A.M.P.]; a UK-US Fulbright Distinguished Scholar Award; the US National Institutes of Health [grant number HD069458 to P.W.J.; HD33816 to M.A.H.; HD42137 to John Eppig, M.A.H. and J.C.S.]; the Priority Program SPP 1384 ‘Mechanisms of genome haploidization’ (to M.A. and R.J.) from the German Science Foundation.Peer Reviewe

A study to assess the effectiveness of instructional activities on dysgraphia among primary school children in selected school at Tirunelveli District

STATEMENT OF THE PROBLEM: The present dissertation was under taken “ A study to assess the effectiveness of Instructional activities on Dysgraphia among primary school children in selected school at Tirunelveli District”. OBJECTIVES: 1. To assess the pre test and post test level of dysgraphia among primary school children. 2. To evaluate the effectiveness of instructional activities on dysgraphia among primary school children. 3. To find out the association between the pre test level of dysgraphia among primary school children with their selected demographic variables. HYPOTHESIS: H1- There will be a significant difference between the pre test and post test level of dysgraphia among primary school children. H2- There will be a significant association between the pre test level of dysgraphia among primary school children with the selected demographic variables. METHODOLOGY: Pre test was conducted to assess the effectiveness of instructional activities on dysgraphia among primary school children. Quantitative research approach with Quasi- experimental, one group pre test & post test design was adopted to determine the effectiveness of instructional activities on dysgraphia. The study was conducted in Swami Vivekananda Primary School in Ramayanpatti, situated in Tirunelveli. Samples were selected by using Stratified random sampling technique with lottery method. The instructional activities was given to the samples in study group for one hour every day –all working days for one month. After one month post test was conducted using the Dysgraphia disability scale by the investigator. The study finding reveals that during pre-test, in study, among 30 primary school children with dysgraphia 26 (86.67%) had mild to moderate disability and 4 (13.33%) had minimal disability of dysgraphia. During post test, in study, among 30 primary school children with dysgraphia 4 (13.33%) had mild to moderate disability, 24 (80%) had minimal disability of dysgraphia and 2(6.66%) were normal level of dysgraphia. The mean score on level of dysgraphia among primary school children in study group were 48.53 in pre test and 57.6 in post test respectively. Standard deviation value were (3.57) in pre test and (4.96) in post test respectively. The mean difference score was 9.07. The paired ‘t’ values were 14.59* which is significant at p < 0.05. Hence the instructional activities was effective in reducing the level of dysgraphia among primary school children. So the research hypothesis was accepted. CONCLUSION: From the results of the study, it is concluded that instructional activities are effective in reducing the level of dysgraphia. Those skills are easy to follow and cost effective. School children can do self instructional activities. Therefore, the investigator felt that more importance should be given to instructional activities to reduce dysgraphia

Critical properties of the double exchange ferromagnet Nd0.4Pb0.4MnO3

Results of a study of dc-magnetization M(T, H), performed on a Nd0.6Pb0.4MnO3 single crystal in the temperature range around T_C (Curie temperature) which embraces the critical region | epsilon | = |T -T_C |/T_C <= 0.05 are reported. The magnetic data analyzed in the critical region using the Kouvel-Fisher method give the values for the T_C =156.47 +/- 0.06 K and the critical exponents, beta = 0.374 +/- 0.006 (from the temperature dependence of magnetization), and gamma = 1.329 +/- 0.003 (from the temperature dependence of initial susceptibility). The critical isotherm M(T_C, H) gives delta = 4.547 +/- 0.1. Thus the scaling law gamma+beta=delta beta is fulfilled. The critical exponents obey the single scaling-equation of state M(H, epsilon) = epsilon^b f_+/- (H/epsilon^(beta + gamma)) where, f_+ for T > T_C and f_- for T< T_C. The exponent values are very close to those expected for the universality class of 3D Heisenberg ferromagnets with short-range interactions.Comment: 19 pages, including 6 figure

Sistem Navigasi pada Unmanned Surface Vehicle untuk Pemantauan Daerah Perairan

Intisari — Daerah perairan, khususnya sungai, memiliki peranan penting untuk kehidupan manusia. Untuk mencegah kerusakan pada daerah tersebut, maka ada baiknya jika dilakukan pemantauan dan pengukuran secara berkala untuk beberapa parameter yang dapat memberi tanda atau peringatan dini terhadap ketidak normalan yang terjadi daerah ini sehingga dapat dilakukan antisipasi secara tepat dan cepat. Atas ide inilah diciptakan sebuah Unmanned Surface Vehicle yang ditujukan untuk mempermudah proses pemantauan daerah perairan. USV yang digunakan yaitu USV elektrik yang dilengkapi APM 2.5 dengan firmware ardurover untuk sistem autopilot. Sistem autopilot pada USV meliputi mode Auto, manual, guided dan hold. Sebelum USV menjalankan misi, dilakukan pengujian-pengujian terhadap sensor-sensor yang dipakai. Kemudian pengujian perairan dilakukan dengan membuat 6 misi dengan letak waypoint yang berbeda sehingga USV dapat menuju titik waypoint yang diinginkan. Didapatkan eror radius rata-rata setiap waypoint sebesar 2,2 meter. USV ini juga dilengkapi dengan sistem FPV sehingga pemantauan dapat lebih mudah dilakukan dengan melihat kamera yang terpasang pada USV dan ditampilkan pada monitor 7” dengan bantuan video sender.Kata kunci— daerah perairan, Unmanned Surface Vehicle (USV), APM 2.5, Sistem FPV Abstract — Water area, especially river, has an important role for human life. To prevent the damage to that area, it is better if we do the monitoring and measurement periodically to some of parameters that can give a sign or early warning against abnormality that occurs in this area, so we can accurately and quickly anticipate. From this idea, we created an Unmanned Surface Vehicle that is intended to facilitate monitoring process in water area. USV that we are use is electric USV equipped with APM 2.5 firmware ardurover as an autopilot system. Autopilot system on USV covered with Auto mode, Manual mode, Guided mode and Hold mode. Before USV take the mission, every sensors in this USV are being tested. Then USV can take the water area mission by making 6 mission with different waypoints location  so that usv can go towards desired waypoints. Average error radius obtained from  mission is 2,2 meter every waypoints. This USV also equipped with FPV system so that monitoring proses can easily done by looking at the camera mounted on the USV. Keywords— Water area, Unmanned Surface Vehicle (USV), APM 2.5, FPV Syste

Dog Breed Identification using ResNet Model

As dogs are domestic animals due to the many numbers of dog breeds available around the world. It’s hard to find out the exact dog breed name for a common person. There are many techniques available to identify dog breed. But the proposed work introduced the new technique called RESNET which is the part of CNN to classify dog. RESNET is used to identify images. It helps to perform different tasks on larger datasets. Identification of different dogs is one of the important applications of Convolutional Neural networks. Since the identification of dog breeds is very difficult because they spread in a large number and it makes very hard for a person to identify or classify dogs. With the help of Keras and TensorFlow, a dataset is created, tested, and trained for the detection of dog breeds by using RESNET. Around 120 different dog breeds are present in the dataset which consist of 20600 images of dogs. From this paper, load these images and convert them into a NumPy array and normalize them. Then,100 epochs were used with a batch size of 128 to achieve the best accuracy. The model is saved for further process to create a web application to identify the dog

Role of Apoptosis in Rabies Viral Encephalitis: A Comparative Study in Mice, Canine, and Human Brain with a Review of Literature

To evaluate the role of apoptosis in rabies encephalitis in humans and canines infected with wild-type street virus, in comparison with rodent model infected with street and laboratory passaged CVS strain, we studied postmortem brain tissue from nine humans, six canines infected with street rabies virus, and Swiss albino mice inoculated intramuscularly (IM) and intracerebrally (IC) with street and CVS strains. Encephalitis and high rabies antigen load were prominent in canine and human brains compared to rodents inoculated with street virus. Neuronal apoptosis was detectable only in sucking mice inoculated with CVS strain and minimal in street virus inoculated mice. In a time point study in suckling mice, DNA laddering was noted only terminally (7 days p.i.) following IC inoculation with CVS strain but not with street virus. In weanling and adult mice, apoptosis was restricted to inflammatory cells and absent in neurons similar to human and canine rabies-infected brains. Absence of neuronal apoptosis in wild-type rabies may facilitate intraneuronal survival and replication while apoptosis in inflammatory cells prevents elimination of the virus by abrogation of host inflammatory response