Is Barbero's Hamiltonian formulation a Gauge Theory of Lorentzian Gravity?

This letter is a critique of Barbero's constrained Hamiltonian formulation of General Relativity on which current work in Loop Quantum Gravity is based. While we do not dispute the correctness of Barbero's formulation of general relativity, we offer some criticisms of an aesthetic nature. We point out that unlike Ashtekar's complex SU(2) connection, Barbero's real SO(3) connection does not admit an interpretation as a space-time gauge field. We show that if one tries to interpret Barbero's real SO(3) connection as a space-time gauge field, the theory is not diffeomorphism invariant. We conclude that Barbero's formulation is not a gauge theory of gravity in the sense that Ashtekar's Hamiltonian formulation is. The advantages of Barbero's real connection formulation have been bought at the price of giving up the description of gravity as a gauge field.Comment: 12 pages, no figures, revised in the light of referee's comments, accepted for publication in Classical and Quantum Gravit

Asymptotics and zeros of Sobolev orthogonal polynomials on unbounded supports

In this paper we present a survey about analytic properties of polynomials orthogonal with respect to a weighted Sobolev inner product such that the vector of measures has an unbounded support. In particular, we are focused in the study of the asymptotic behaviour of such polynomials as well as in the distribution of their zeros. Some open problems as well as some new directions for a future research are formulated.Comment: Changed content; 34 pages, 41 reference

Effects of APOE4 allelic dosage on lipidomic signatures in the entorhinal cortex of aged mice

Apolipoprotein E ε4 (APOE4) is the primary genetic risk factor for the late-onset form of Alzheimer's disease (AD). Although the reason for this association is not completely understood, researchers have uncovered numerous effects of APOE4 expression on AD-relevant brain processes, including amyloid beta (Aβ) accumulation, lipid metabolism, endosomal-lysosomal trafficking, and bioenergetics. In this study, we aimed to determine the effect of APOE4 allelic dosage on regional brain lipid composition in aged mice, as well as in cultured neurons. We performed a targeted lipidomic analysis on an AD-vulnerable brain region (entorhinal cortex; EC) and an AD-resistant brain region (primary visual cortex; PVC) from 14-15 month-old APOE3/3, APOE3/4, and APOE4/4 targeted replacement mice, as well as on neurons cultured with conditioned media from APOE3/3 or APOE4/4 astrocytes. Our results reveal that the EC possesses increased susceptibility to APOE4-associated lipid alterations compared to the PVC. In the EC, APOE4 expression showed a dominant effect in decreasing diacylglycerol (DAG) levels, and a semi-dominant, additive effect in the upregulation of multiple ceramide, glycosylated sphingolipid, and bis(monoacylglycerol)phosphate (BMP) species, lipids known to accumulate as a result of endosomal-lysosomal dysfunction. Neurons treated with conditioned media from APOE4/4 vs. APOE3/3 astrocytes showed similar alterations of DAG and BMP species to those observed in the mouse EC. Our results suggest that APOE4 expression differentially modulates regional neuronal lipid signatures, which may underlie the increased susceptibility of EC-localized neurons to AD pathology

Oneida nation of New York: health needs assessment 1990

This is the report of a health needs assessment for the Oneida Indian Nation of New York (ONNY). This needs assessment was conducted in order to collect population-based data related to behavioral risks and reproductive health for Oneida males and females. The survey of the Oneida was initiated because there is almost no risk factor data available on Indian tribes of the northeast, and none available for the Oneida Nation of New York. There are four primary goals for the 1990 Oneida Nation Health Needs Assessment. They are 1) to collect behavioral risk factor and reproductive health data for adult Oneida Nation members living on or near Oneida Nation lands, 2) to assess the current basic health needs of the ONNY, 3) to document the medical providers and hospitals which are currently being utilized by the Nation members and. 4) to develop recommendations for use by health planners from this baseline data.The Oneida Nation Health Needs Assessment (ONHNA) was carried out among enrolled members of the Oneida Nation who were 18 years of age and older who lived in the six counties that are contiguous to the Oneida Nation lands. The Nation Enrollment List was used to identify the Oneida population located in the six-county area. The choice to interview only adults was made to avoid legal difficulties in interviewing minors. Interviewing was conducted in each household face-to-face rather than using mailed questionnaires or telephone contact. All interviewers were enrolled Oneida Nation members. Interviews were conducted by interviewers of the same sex as the respondent. All interviewers participated in one week of training prior to the start of the field work. Four types of data were collected. First, the behavioral risk factors surveyed were related to the 10 leading causes of death in the United States. Behavioral factors include seat belt usage, physical exercise, diet, cigarette and smokeless tobacco usage, alcohol consumption, and the existence of high blood pressure. The second data set included health needs. The survey questions dealt with the prevalence of current diseases and health problems among the Oneidas, and with whether the Oneida people have routine screening tests such as cholesterol, diabetes, and hypertension, and eye exams, pap smears, breast exams, and rectal exams. The third set of data questions focused on reproductive health factors. Questions covered topics such as fertility, contraception, and general maternal-child health conditions. The fourth and final set of questions gathered data on health care utilization. This data will be used to establish health provider contracts with physicians, dentists, pediatricians, and hospitals to provide quality health care for a more reasonable cost. For each risk factor, comparisons were made between the Oneida Nation and data from the 1988 New York State Behavioral Risk Factor Survey.The individual completion rates were 54% for females and 69% for males for a total of 211 respondents in all. The following is an abbreviated summary of selected data from the survey. Seat belt use was only slightly lower than for all New Yorkers. Non-use was highest among young drivers. Sixty percent of Oneida males and 78 percent of Oneida females reported having their blood pressure taken within a year of the survey. All Oneida members were more active physically than the general New York population. However, all Oneida members were more likely to be overweight by comparison Forty percent of all Oneida people are smokers compared to 25 percent of the New York population. Fifty-seven percent of Oneida males and 32 percent of Oneida females are classified as acute and heavy drinkers. Percentages for regular health checks across all factors vary considerably among the Oneida people. Several areas of concern were identified including cholesterol checks, diabetes screening, rectal exams and mammograms. The completed fertility of the Oneida women in this survey is 2.1 children which is lower than that of all U.S. women surveyed in the 1980 census. Female sterilization is the most prevalent contraceptive method among Oneida women. as it is among the general U.S. population.With respect to behavioral risks, cigarette smoking and alcohol consumption are of major concern. This impacts on concerns for overall reproductive health. The task now is to identify the highest priority objectives and to secure resources needed to accomplish these tasks

SLC11A1 polymorphisms and host susceptibility to cutaneous leishmaniasis in Pakistan.

Background:The vector-borne cutaneous leishmaniasis (CL) is endemic in several regions of Pakistan mainly affecting poor populations. Host genetic factors, particularly SLC11A1 (solute carrier transmembrane protein) within macrophages, play a crucial role in disease pathology and susceptibility. Association of SLC11A1 with cutaneous leishmaniasis, a neglected tropical disease, is not well established. Inconsistencies have been observed within different populations worldwide with respect to genetic susceptibility. This study was designed to investigate genetic variation(s) in SLC11A1 and to assess possible association with cutaneous leishmaniasis in Pakistan. Results: Eight polymorphisms (rs2276631, rs3731864, rs2290708, rs2695342, rs201565523, rs17215556, rs17235409, rs17235416) were genotyped across SLC11A1 in 274 patients and 119 healthy controls. Six polymorphisms were studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing. Two single nucleotide polymorphisms were analyzed with newly designed semi-nested PCR assays. Case-control analysis showed no association between selected polymorphisms in SLC11A1 and cutaneous leishmaniasis. No significant difference was observed in the distribution of alleles between leishmaniasis patients and healthy individuals. Strong pairwise linkage disequilibrium was observed between rs2276631 and rs2290708 (r 2 = 64); and rs17235409 and rs17235416 (r 2 = 78). Conclusions: This study shows that genetic variations in the candidate gene SLC11A1 do not affect susceptibility to cutaneous leishmaniasis in the sample population from Pakistan