Retinal Dysplasia Mimicking Retinoblastoma.

Retinal dysplasia represents a congenital disorder characterized by abnormal proliferation of retinal tissue causing leukocoria. We present a case of an infant with bilateral leukocoria, clinically diagnosed as retinoblastoma, followed by enucleation of the left eye. Microscopy however, demonstrated retinal dysplasia consisting of a disorderly proliferation of retinal tissue with formation of rosettes, mimicking retinoblastoma. Microscopic features that aid in differentiating this lesion from retinoblastoma are discussed

Why do education vouchers fail at the ballot box?

We compare a uniform voucher regime against the status quo mix of public and private education, focusing on the distribution of welfare gains and losses across house- holds by income. We argue that the topping-up option available under uniform vouchers is not sufficiently valuable for the poorer households, so the voucher regime is defeated at the polls. Our result depends critically on the opting-out feature in the current system.Education ; Households

Why do education vouchers fail at the ballot box?

We compare a uniform voucher regime against the status quo mix of public and private education, focusing on the distribtuion of welfare gains and losses across households by income. We argue that the topping-up option available under uniform vouchers is not su¢ ciently valuable for the poorer households, so the voucher regime is defeated at the polls. Our result depends critically on the opting-out feature in the current system.vouchers, political economy, opting out, education finance

Why do Education Vouchers Fail?

We examine quantitatively why uniform vouchers have repeatedly su¤ered electoral defeats against the current system where public and private schools coexist. We argue that the topping-up option available under uniform vouchers is not sufficiently valuable for the poorer households to prefer the uniform vouchers to the current mix of public and private education. We then develop a model of publicly funded means-tested edu- cation vouchers where the voucher received by each household is a linearly decreasing function of income. Public policy, which is determined by majority voting, consists of two dimensions: the overall funding level (or the tax rate) and the slope of the means testing function. We solve the model when the political decisions are sequential ?households vote ?rst on the tax rate and then on the extent of means testing. We establish that a majority voting equilibrium exists. We show that the means-tested voucher regime is majority preferred to the status-quo. These results are robust to alternative preference parameters, income distribution parameters and voter turnout.

Stable and Metastable vortex states and the first order transition across the peak effect region in weakly pinned 2H-NbSe_2

The peak effect in weakly pinned superconductors is accompanied by metastable vortex states. Each metastable vortex configuration is characterized by a different critical current density J_c, which mainly depends on the past thermomagnetic history of the superconductor. A recent model [G. Ravikumar, et al, Phys. Rev. B 61, R6479 (2000)] proposed to explain the history dependent J_c postulates a stable state of vortex lattice with a critical current density J_c^{st}, determined uniquely by the field and temperature. In this paper, we present evidence for the existence of the stable state of the vortex lattice in the peak effect region of 2H-NbSe_2. It is shown that this stable state can be reached from any metastable vortex state by cycling the applied field by a small amplitude. The minor magnetization loops obtained by repeated field cycling allow us to determine the pinning and "equilibrium" properties of the stable state of the vortex lattice at a given field and temperature unambiguously. The data imply the occurence of a first order phase transition from an ordered phase to a disordered vortex phase across the peak effect.Comment: 20 pages, 10 figures. Corresponding author: S. Ramakrishna

Coreference detection of low quality objects

The problem of record linkage is a widely studied problem that aims to identify coreferent (i.e. duplicate) data in a structured data source. As indicated by Winkler, a solution to the record linkage problem is only possible if the error rate is sufficiently low. In other words, in order to succesfully deduplicate a database, the objects in the database must be of sufficient quality. However, this assumption is not always feasible. In this paper, it is investigated how merging of low quality objects into one high quality object can improve the process of record linkage. This general idea is illustrated in the context of strings comparison, where strings of low quality (i.e. with a high typographical error rate) are merged into a string of high quality by using an n-dimensional Levenshtein distance matrix and compute the optimal alignment between the dirty strings. Results are presented and possible refinements are proposed

Comparison of History Effects in Magnetization in Weakly pinned Crystals of high-TcT_c and low-Tc_c Superconductors

A comparison of the history effects in weakly pinned single crystals of a high $T_c$ YBa$_2$Cu$_3$O$_{7 - \delta}$ (for H $\parallel$ c) and a low $T_c$ Ca$_3$Rh$_4$Sn$_{13}$, which show anomalous variations in critical current density $J_c(H)$ are presented via tracings of the minor magnetization hysteresis loops using a vibrating sample magnetometer. The sample histories focussed are, (i) the field cooled (FC), (ii) the zero field cooled (ZFC) and (iii) an isothermal reversal of field from the normal state. An understanding of the results in terms of the modulation in the plastic deformation of the elastic vortex solid and supercooling across order-disorder transition is sought.Comment: Presented in IWCC-200

Minimum and maximum against k lies

A neat 1972 result of Pohl asserts that [3n/2]-2 comparisons are sufficient, and also necessary in the worst case, for finding both the minimum and the maximum of an n-element totally ordered set. The set is accessed via an oracle for pairwise comparisons. More recently, the problem has been studied in the context of the Renyi-Ulam liar games, where the oracle may give up to k false answers. For large k, an upper bound due to Aigner shows that (k+O(\sqrt{k}))n comparisons suffice. We improve on this by providing an algorithm with at most (k+1+C)n+O(k^3) comparisons for some constant C. The known lower bounds are of the form (k+1+c_k)n-D, for some constant D, where c_0=0.5, c_1=23/32=0.71875, and c_k=\Omega(2^{-5k/4}) as k goes to infinity.Comment: 11 pages, 3 figure

The Homo Neanderthalis and the Dravidians: A Common Origin and Relation to Harappan Civilisation and Vedas

INTRODUCTION: The postulated Lemurian part of the Indian sub-continent in South India is inhabited by the dominant Nair community. The dominant Nair community also has a high incidence of autism. Neanderthal anthropometric features have been described in autism. Neanderthal metabolonomics have also been described in autism. It is possible that homo neanderthalis would have originated in the super continent which occupied the southern ocean. The island of Sumatra is home to another human species homo floresiensis which lived along with homo neanderthalis. This suggests an oceanic origin of homo neanderthalis in the supercontinent in the southern ocean. Recurrent Tsunamis would have forced the migration of homo neanderthalis to the Eurasian land mass especially to Harappa, Sumeria, Etruscia, Egypt and Basque country. There is a high incidence of Neanderthal genes in the Basque population. The language spoken in Harappa, Sumeria, Etruscia, Egypt and Basque country had a Dravidian sub-stratum. The population in these areas are matrilineal and female dominant.MATERIALS AND METHODS: Neanderthal anthropometric features were evaluated in the Nair community and in autism. The parameters checked include dolichocephalic skull, prominent supraorbital ridge and mid face large flat nose and ring finger index finger ratios.RESULTS: The Nair community had a high prevalence of Neanderthal anthropometric features. Neanderthal anthropometric features were also dominant in autism.CONCLUSION: This suggests an out of oceania hypothesis for the origin of homo neanderthalis

The Extinction of Homo Sapiens and Symbiotic Neanderthalisation: Relation to Archaeal Mediated RNA Viroidsand Amyloidosis

Introduction: Prion proteins have been implicated in systemic disorders like neurodegenerations, cancer and metabolic syndrome. The beta amyloid in Alzheimer’s disease, alpha synuclein in parkinson’s disease, the TAR protein in frontotemporal dementia and copper zinc dismutase in motor neuron disease behaves like prion proteins. Prion proteins like behavior is also seen in the tumour suppressor P53 protein in cancer and the islet cell associated amyloid in diabetes mellitus. Prion diseases are conformational diseases. The abnormal prion protein seeded into the system converts the normal proteins with prion like domains to abnormal configuration. This abnormal protein resists digestion by lysosomal enzymes after its half-life is over and results in deposition of amyloid plaques. This produces organ dysfunction. Prion phenomena were initially described for Creutzfeldt Jakob’s disease, but now it is found to be wide spread in chronic disease pathogenesis. Ribonucleoproteins are well known to behave like prion proteins and form amyloid. We have demonstrated actinidic archaea which secretes RNA viroids in metabolic syndrome, neurodegenerations, cancer, autoimmune disease, schizophrenia, autism and CJD. The RNA viroids can bind with normal proteins with prion like domains eg., superoxide dismutase and produce a ribonucleoprotein resulting in prion phenomena and amyloidogenesis.Materials and Methods: The following groups were included in the study:- alzheimer’s disease, multiple sclerosis, non-hodgkin’s lymphoma, metabolic syndrome x with cerebrovascular thrombosis and coronary artery disease, schizophrenia, autism, seizure disorder, creutzfeldt jakob disease and acquired immunodeficiency syndrome. There were 10 patients in each group and each patient had an age and sex matched healthy control selected randomly from the general population. The blood samples were drawn in the fasting state before treatment was initiated. Plasma from fasting heparinised blood was used and the experimental protocol was as follows (I) Plasma+phosphate buffered saline, (II) same as I+cholesterol substrate, (III) same as II+cerium 0.1 mg/ml, (IV) same as II+ciprofloxacine and doxycycline each in a concentration of 1 mg/ml. Cholesterol substrate was prepared as described by Richmond. Aliquots were withdrawn at zero time immediately after mixing and after incubation at 37oC for 1 hour. The following estimations were carried out:- Cytochrome F420, free RNA, Cytochrome F420 was estimated flourimetrically (excitation wavelength 420 nm and emission wavelength 520 nm). Results: Plasma of control subjects showed increased levels of the above mentioned parameters with after incubation for 1 hour and addition of cholesterol substrate resulted in still further significant increase in these parameters. The plasma of patients showed similar results but the extent of increase was more. The addition of antibiotics to the control plasma caused a decrease in all the parameters while addition of cerium increased their levels. The addition of antibiotics to the patient’s plasma caused a decrease in all the parameters while addition of cerium increased their levels but the extent of change was more in patient’s sera as compared to controls. Discussion: The actinidic archaeal growth results in increased digoxin synthesis and phenotypic conversion of homo sapiens to homo Neanderthals as reported earlier. The increased actinidic archaeal growth is due to global warming and these results in neanderthalisation.Homo neanderthalis tend to have more of civilisational diseases like metabolic syndrome, neurodegenerations, cancer, autoimmune disease, schizophrenia, autism and CJD. Actinidic archaeal secreted RNA viroids may play a crucial role in amyloid formation and pathogenesis of these disorders. The evolution and origin of homo sapiens and homo neanderthalis is on the basis of actinidic archaeal symbiosis and digoxin synthesis. Extreme climate change related increased actinidic archaeal symbiosis and digoxin synthesis results in homo neanderthalis. The homo sapien species results from inhibition of actinidic archaeal symbiosis and endogenous digoxin synthesis by normal global climate. Thus there are evolutionary swings between the two human species depending on extremes of climate and archaeal symbiosis. Endogenous digoxin can be considered as a Neanderthal hormone. The results show that there was increase in cytochrome F420 in CJD and other disease groups indicating increased archaeal growth. There was also an increase in free RNA indicating self-replicating RNA viroids in CJD and other disease groups. The RNA viroid generation was catalysed by actinides. The RNA viroids can bind with proteins having prion like domains forming ribonucleoproteins. These ribonucleoproteins can give an abnormal conformation to the protein resulting in generation of abnormal prions. The abnormal prions can act as a template to convert normal proteins with normal configuration to abnormal conformation. This can result in amyloidogenesis. The abnormal configured proteins will resist lysosomal digestion and accumulate as amyloid producing disease states and extinction