Effects of different doses of x-rays on meiotic chromosomes of malePhysopelta schlanbuschi (Largidae: Heteroptera)

Male largid bugs,Physopelta schlanbuschi, having 2n=17 chromosomes (12 autosomes +2m+X1X2Y), were irradiated with x-ray doees of 300 r, 400 r and 500 r which yielded various types of chromosome aberrations in different stages of meiosis of which the common forms were breaks, fragment of unknown origin, constriction, gap etc. Among the 3 sex chromosomes, the two conspicuously large markers, X1 and Y, sometimes formed chiasmalike configuration in prophase I and metaphase I, while a number of anaphase I plates had a chromatid bridge, very likely formed by the X1 and the Y. The qualitative and quantitative assessments of chromosome aberrations in spermatogonial metaphase, prophase I, metaphase I, anaphase I and metaphase II were made at 13 intervals for the doses of 300 r and 400 r and 14 intervals for 500 r between 5 min and 1 week or more. The data showed over-all dose-dependent aberration effects and the sex chromosomes appeared relatively more vulnerable than the autosomes to different doses of x-rays. The testes of untreated males taken as controls had practically no aberration

The bacterium, Staphylococcus aureus induced chromosome aberrations with their protection by penicillin, and mitotic inhibition in Syrian hamsters

The frequency of bone marrow chromosome aberrations in Syrian hamster, Mesocricetus auratus induced by the injection of log culture, saline suspension and culture filtrate of S. aureus was significantly high while the treatment of heat-killed bacterial suspension showed no difference with control data. In the first three treated series aberrations were of individual and gross types while others had only individual types. The chromatid breaks were nonrandom, the centro-meric region being less vulnerable and the distal region was more susceptible. The aberration frequency was significantly reduced when log culture, saline suspension and culture filtrate treated specimens were also injected with penicillin 1 hr before simultaneously and 1 hr after, of which the post-treatment rendered the maximum protection. Lastly, the treatment of isolated bacterial sample retarded the mitotic frequency significantly as compared to that of normal and controls

Effect of X-rays on the somatic chromosomes of the exotic fish, Tilapia mossambica

Male and female T. mossambica were x-rayed with 100 r and the meta-phase chromosome aberrations in their gill epithelia were studied at 13 different intervals against suitable control. The chromosomes of males appeared more radiosensitive than those of females. Among the diploid complement of 44 chromosomes, the individual type aberrations were non-random in both sexes. The longest pair of chromosomes, taken as the marker pair, was found very highly radio-sensitive, while the remaining 21 pairs as non-markers were somewhat resistant to x-radiation when the observed and the expected numbers were subjected to statistical analysis. The break in the marker chromosome was also non-randomly distributed as the distal half had a significantly large number of breaks

Nonuniversal exponents in sandpiles with stochastic particle number transfer

We study fixed density sandpiles in which the number of particles transferred to a neighbor on relaxing an active site is determined stochastically by a parameter $p$. Using an argument, the critical density at which an active-absorbing transition occurs is found exactly. We study the critical behavior numerically and find that the exponents associated with both static and time-dependent quantities vary continuously with $p$.Comment: Some parts rewritten, results unchanged. To appear in Europhys. Let

STUDY ON AVAILABILITY AND AFFORDABILITY OF ANTI HYPERTENSIVE MEDICINES IN THE STATE OF KERALA

Objective: Since the 1970s, one of the smallest Indian States, Kerala, has been internationally applauded for its excellent performance in its health indicators. Even if mortality is low, the morbidity (those suffering from chronic/non-communicable diseases) levels in urban and rural is high in Kerala compared to other Indian states. Gradually, the public sector becomes incapable to convene the demands for health care and people have responded to this meagerness by increasing the use of an emerging private sector. To overcome this scenario, Kerala government established KMSCL for promoting access to medicines to the patients approaching the public hospitals in Kerala by making available selected essential medicines at free of cost. The present study was conducted to evaluate the availability, cost and affordability of anti-hypertensive medicines in Kerala. Methods: This prospective, observational study was conducted in Trivandrum district in Kerala, from June 2013 to November 2013. Three types of medication prices were taken into contemplation with the intension for calculation purposes, the highest and the lowest branded medication costs in private pharmacy and Karunya Community Pharmacy (KCP) prices. Affordability was calculated for the different level of skilled workers and through the wages fixed by the government of Kerala for these categories, who were consuming the medications at the time. A comparison was also done between various treatment guidelines of hypertension. Results: There was 15.5% to 230% price variation between the highest and lowest price of branded anti-hypertensive medicines respectively. For treating Stage 3 of hypertension; unskilled and highly skilled workers had to spend a minimum of 1.22 and 0.84 wage days respectively and a maximum of 5.23 and 4.34 wage days respectively in private pharmacies. All the medicines required for the treatments of hypertension were available in both private and KCP. Conclusion: The study revealed that there was an average availability at of antihypertensive medicines in public health facilities. The availability of all medicines at KCP in low price shows the good impact of KMSCL for promoting access of medicines to the poor

Universal scaling behavior at the upper critical dimension of non-equilibrium continuous phase transitions

In this work we analyze the universal scaling functions and the critical exponents at the upper critical dimension of a continuous phase transition. The consideration of the universal scaling behavior yields a decisive check of the value of the upper critical dimension. We apply our method to a non-equilibrium continuous phase transition. But focusing on the equation of state of the phase transition it is easy to extend our analysis to all equilibrium and non-equilibrium phase transitions observed numerically or experimentally.Comment: 4 pages, 3 figure

Order Parameter and Scaling Fields in Self-Organized Criticality

We present a unified dynamical mean-field theory for stochastic self-organized critical models. We use a single site approximation and we include the details of different models by using effective parameters and constraints. We identify the order parameter and the relevant scaling fields in order to describe the critical behavior in terms of usual concepts of non equilibrium lattice models with steady-states. We point out the inconsistencies of previous mean-field approaches, which lead to different predictions. Numerical simulations confirm the validity of our results beyond mean-field theory.Comment: 4 RevTex pages and 2 postscript figure

Scaling behavior of the absorbing phase transition in a conserved lattice gas around the upper critical dimension

We analyse numerically the critical behavior of a conserved lattice gas which was recently introduced as an example of the new universality class of absorbing phase transitions with a conserved field [Phys. Rev. Lett. 85, 1803 (2000)]. We determine the critical exponent of the order parameter as well as the critical exponent of the order parameter fluctuations in D=2,3,4,5 dimensions. A comparison of our results and those obtained from a mean-field approach and a field theory suggests that the upper critical dimension of the absorbing phase transition is four.Comment: 5 pages, 11 figure

Intrinsic Half-Metallicity in Modified Graphene Nanoribbons

We perform first-principles calculations based on density functional theory to study quasi one-dimensional edge-passivated (with hydrogen) zigzag graphene nanoribbons (ZGNRs) of various widths with chemical dopants, boron and nitrogen, keeping the whole system isoelectronic. Gradual increase in doping concentration takes the system finally to zigzag boron nitride nanoribbons (ZBNNRs). Our study reveals that, for all doping concentrations the systems stabilize in anti-ferromagnetic ground states. Doping concentrations and dopant positions regulate the electronic structure of the nanoribbons, exhibiting both semiconducting and half-metallic behaviors as a response to the external electric field. Interestingly, our results show that ZBNNRs with terminating polyacene unit exhibit half-metallicity irrespective of the ribbon width as well as applied electric field, opening a huge possibility in spintronics device applications.Comment: 4 pages, 5 figures (low resolution), accepted for publication in Physical Review Letter