89 research outputs found
Geometric Singularities and Enhanced Gauge Symmetries
Using ``Tate's algorithm,'' we identify loci in the moduli of F-theory
compactifications corresponding to enhanced gauge symmetry. We apply this to
test the proposed F-theory/heterotic dualities in six dimensions. We recover
the perturbative gauge symmetry enhancements of the heterotic side and the
physics of small instantons, and discover new mixed
perturbative/non-perturbative gauge symmetry enhancements. Upon further
toroidal compactification to 4 dimensions, we derive the chain of Calabi-Yau
threefolds dual to various Coulomb branches of heterotic strings.Comment: 49 pages harvmac big (must print in big mode for tables to appear
correctly); Typos and reference correcte
Efficiency of Fenbendazole on the Basis of Nanosized Supramolecular Delivery Systems with Polyvinyl Pyrrolidone and Dioctylsulphosuccinate Sodium in the Cases of Helminthosis
The purpose of the research is to study the efficiency of fenbendazole on the basis of nanosized supramolecular delivery systems with polyvinyl pyrrolidone and dioctylsulphosuccinate sodium in the cases of helminthosis in animals.Materials and methods. Experiments were conducted on 120 mice experimentally infected by Trichinella spiralis, Hymenolepis nana and on sheep experimentally infected by gastro-intestinal eelworms (120 animals) and by moniezias (60 animals). In each case of helminthosis animals from different groups (10 animals in each) were given fenbendazole supramolecular complex with polyvinyl pyrrolidone and dioctylsulphosuccinate sodium orally at the single dose of 3.0, 2.0 and 1.0 mg/kg on AS compared to background drug fenbendazole at a dose of 2.0 mg/kg. Group of animals, which did not receive a drug was a control. Drug efficiency calculated according to the results of mice enterotomy and data of coproovoscopic studies of sheep by flotation technique before and in 15 days after drug administration.Results and discussion. Fenbendazole supramolecular complex with polyvinyl pyrrolidone and dioctylsulphosuccinate sodium at the doses of 3.0, 2.0 and 1.0 on AS showed 100, 100 and 87.7 % of efficiency against T. spiralis, 100, 100, 91.14% against H. nana, 100, 97.7 and 94.0% against gastro-intestinal eelworms and 100, 92.44 and 44.26% against Moniezia expansa, respectively while efficiency of background drug – fenbendazole substance was 23.0–26.3%
Mapping 6D N = 1 supergravities to F-theory
We develop a systematic framework for realizing general anomaly-free chiral
6D supergravity theories in F-theory. We focus on 6D (1, 0) models with one
tensor multiplet whose gauge group is a product of simple factors (modulo a
finite abelian group) with matter in arbitrary representations. Such theories
can be decomposed into blocks associated with the simple factors in the gauge
group; each block depends only on the group factor and the matter charged under
it. All 6D chiral supergravity models can be constructed by gluing such blocks
together in accordance with constraints from anomalies. Associating a geometric
structure to each block gives a dictionary for translating a supergravity model
into a set of topological data for an F-theory construction. We construct the
dictionary of F-theory divisors explicitly for some simple gauge group factors
and associated matter representations. Using these building blocks we analyze a
variety of models. We identify some 6D supergravity models which do not map to
integral F-theory divisors, possibly indicating quantum inconsistency of these
6D theories.Comment: 37 pages, no figures; v2: references added, minor typos corrected;
v3: minor corrections to DOF counting in section
Families of Canonical Transformations by Hamilton-Jacobi-Poincar\'e equation. Application to Rotational and Orbital Motion
The Hamilton-Jacobi equation in the sense of Poincar\'e, i.e. formulated in
the extended phase space and including regularization, is revisited building
canonical transformations with the purpose of Hamiltonian reduction. We
illustrate our approach dealing with orbital and attitude dynamics. Based on
the use of Whittaker and Andoyer symplectic charts, for which all but one
coordinates are cyclic in the Hamilton-Jacobi equation, we provide whole
families of canonical transformations, among which one recognizes the familiar
ones used in orbital and attitude dynamics. In addition, new canonical
transformations are demonstrated.Comment: 21 page
An update on semen quality among young Finnish men and comparison with Danish data
Finnish men used to have higher semen quality than Danish men. However, recent studies showed that semen quality in Finland has declined, but it has been relatively stable in Denmark.\nThis study aimed to compare new data on semen quality of the young Finnish men to that of Danish men.\nIn this cross-sectional study, 18- to 19-year-old men residing in Turku, Finland and Copenhagen, Denmark, were invited to participate in 2008-2011. Each man filled in a questionnaire, provided one semen sample and underwent andrological examination. Semen samples were analyzed according to WHO. Multiway ANOVA was used to adjust semen variables for duration of sexual abstinence and age (and time from ejaculation to the start of semen analysis for sperm motility).\nAltogether 287 Finnish men and 873 Danish men participated in the study. The adjusted median sperm concentrations were 49 and 47 million/mL for Finnish and Danish men, respectively (p = 0.48). The adjusted median total sperm counts were 148 million in Finland and 146 million in Denmark (p = 0.87). The adjusted median percentages of morphologically normal spermatozoa were 6.9% in Finland and 6.5% in Denmark, p = 0.27. Finnish men had higher adjusted median percentages of motile spermatozoa (A+B+C) than Danish men (80% vs. 69%, p < 0.001). The proportion of men who had low semen quality (sperm concentration, percentage of morphologically normal spermatozoa or percentage of progressively motile spermatozoa below WHO reference limits) was lower in Finland (25.4%) than in Denmark (34.6%), p = 0.004.\nConsiderable percentage of men in both countries had low semen quality. The deteriorating semen quality in Finland may result in decreasing fecundity, which is a cause of concern.\nThe formerly high semen quality in Finland has converged to the lower Danish levels. Our findings demonstrate the importance of continuing surveillance of semen quality.\nBACKGROUND\nOBJECTIVE\nMATERIALS AND METHODS\nRESULTS\nDISCUSSION\nCONCLUSIO
Charge Lattices and Consistency of 6D Supergravity
We extend the known consistency conditions on the low-energy theory of
six-dimensional N = 1 supergravity. We review some facts about the theory of
two-form gauge fields and conclude that the charge lattice Gamma for such a
theory has to be self-dual. The Green-Schwarz anomaly cancellation conditions
in the supergravity theory determine a sublattice of Gamma. The condition that
this sublattice can be extended to a self-dual lattice Gamma leads to a strong
constraint on theories that otherwise appear to be self-consistent.Comment: 15 pages. v2: minor changes; references, additional example added;
v3: minor corrections and clarifications added, JHEP versio
Features of Morphometric Changes in Platelets and Red Blood Cells in Women with Various Forms of Hypertensive Disorders in the Third Trimester of Pregnancy
Background. Arterial hypertension during pregnancy is accompanied by pronounced changes in microcirculation and hemostasis in the system, the state of which is largely determined by the structural and functional properties of red blood cells and platelets. The study of quantitative and morphometric characteristics of blood cells will expand the existing understanding of their role in the pathogenesis of hypertensive disorders.Aim of the research. To study the quantitative and morphometric indicators of red blood cells and platelets in pregnant women with various forms of hypertensive disorders, on the basis of which to develop an additional method for the diagnosis of preeclampsia. Materials and methods. 237 women in the third trimester of pregnancy were examined. The main group (167 women) included patients with various forms of hypertensive disorders. The comparison group included 70 pregnant women without signs of hypertensive disorders. The characteristic of clinical and anamnestic data of the studied groups is given. A comparative analysis of the number and morphometric parameters of red blood cells and platelets was performed.Results. With moderate and severe preeclampsia, a decrease in the level of red blood cells, hemoglobin and hematocrit was not accompanied by changes in red blood cell indices. In women with preeclampsia, regardless of the presence of chronic arterial hypertension, an increase in the average dry weight, average volume and degree of platelet anisocytosis was detected. In severe preeclampsia and preeclampsia with underlying of chronic arterial hypertension, an increase in the number of large forms of platelets and their granulocytosis was revealed, and in addition, in severe cases of preeclampsia, a decrease in platelet level was noted.Conclusions. Modern hematological analyzers make it possible to establish the nature of not only quantitative, but also morphometric changes in red blood cells and platelets, thereby complementing the existing understanding of the pathogenetic mechanisms underlying hypertensive disorders in pregnancy. Using average dry platelet mass and average blood pressure may be useful in diagnosing preeclampsia
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