1,377 research outputs found
Moduli Spaces of Lumps on Real Projective Space
Harmonic maps that minimize the Dirichlet energy in their homotopy classes are known as lumps. Lump solutions on real projective space are explicitly given by rational maps subject to a certain symmetry requirement. This has consequences for the behaviour of lumps and their symmetries. An interesting feature is that the moduli space of charge three lumps is a D2-symmetric 7-dimensional manifold of cohomogeneity one. In this paper, we discuss the charge three moduli spaces of lumps from two perspectives: discrete symmetries of lumps and the Riemann-Hurwitz formula. We then calculate the metric and find explicit formula for various geometric quantities. We also discuss the implications for lump decay
Hexagonal Structure of Baby Skyrmion Lattices
We study the zero-temperature crystalline structure of baby Skyrmions by
applying a full-field numerical minimization algorithm to baby Skyrmions placed
inside different parallelogramic unit-cells and imposing periodic boundary
conditions. We find that within this setup, the minimal energy is obtained for
the hexagonal lattice, and that in the resulting configuration the Skyrmion
splits into quarter-Skyrmions. In particular, we find that the energy in the
hexagonal case is lower than the one obtained on the well-studied rectangular
lattice, in which splitting into half-Skyrmions is observed.Comment: RevTeX, 7 pages, 6 figure
Imaging review of the lung parenchymal complications in patients with IPF
Idiopathic pulmonary fibrosis (IPF) is a chronic, pulmonary-limited, interstitial lung disease with a poor prognosis. This condition is characterized by different clinical scenarios, ranging from the most typical slow and progressive deterioration of symptoms to a rapid and abrupt decline of lung function. Rapid worsening of clinical course is due to superimposed complications and comorbidities that can develop in IPF patients, with a higher incidence rate compared to the general population. These conditions may require a different management of the patient and a therapy adjustment, and thus it is fundamental to recognize them. High Resolution Computed Tomography (HRCT) is sensitive, but not specific, in detecting these complications, and can evaluate the presence of radiological variations when previous examinations are available; it recognizes ground glass opacities or consolidation that can be related to a large spectrum of comorbidities, such as infection, lung cancer, or acute exacerbation. To reach the final diagnosis, a multidisciplinary discussion is required, particularly when the clinical context is related to imaging findings
Prevention of fecal-orally transmitted diseases in travelers through an oral anticholeric vaccine (WC/rBS)
Introduction. Estimate the efficacy of oral anticholeric vaccine Dukoral® in subjects travelling to high-risk areas for traveler?s diarrhoea and cholera.
Methods. The study involved subjects of both genders who planned to travel to high-risk areas for traveler?s diarrhoea and cholera. Immunization with oral anticholeric vaccine Dukoral® was offered to each one of them. Upon returning, all the participants in the study were asked to complete a self-administered questionnaire consisting of 40 close-ended questions mainly concerning: personal and health data, characteristics (length, destination, reason) of the travel, onset of gastrointestinal symptoms, data relating to the assumption of anti- choleric vaccine and possible adverse reactions.
Results. 296 questionnaires have been collected. Mean age was 38.2 years (55.4% males and 44.6% females). Mean travel length was 22.2 days. Reasons for the travel: 66.8% tourism and 33.2% work-cooperation. Most frequent destination was Africa (48.1%), followed by Asia (32.1%) and Central South- America (17.8%). 199 subjects (67.2%) properly executed vac- cination with Dukoral®. The diarrhoea affected 14.1% of vacci- nated subjects and 20.6% of non vaccinated ones. The following cohorts showed statistically significant differences in incidence of diarrhoea: inf. 35 years old age (13.7% vs. 27.1%), travel for work-cooperation (14.1% vs. 35%) and travel length > 28 days (12.1% vs. 40%). No serious adverse events were reported fol- lowing vaccination.
Discussion. Oral Anticholeric vaccine proved to be effective and safe in preventing fecal-oral diseases in travelers exposed to high risk conditions
Pliocene-Quaternary mass wasting along the Ionian Calabrian margin, offshore southern Italy
The Ionian Calabrian margin, offshore southern Italy, is a tectonically active area, located above a subduction zone dominated by the rollback of the African plate. A variety of mass wasting features are known to occur along the inner continental slope, based on seafloor mapping during the Italian project MaGIC (Marine Geohazards Along the Italian Coasts). New high-resolution geophysical data are available from a wider area following two surveys, in 2014 of the German RV Meteor, which acquired multibeam bathymetry (50 m DTM) and Parasound sub-bottom profiles, and in 2015 of the Italian RV OGS Explora, which acquired Chirp sub-bottom and multichannel seismic reflection profiles. Here we integrate these data with existing geophysical datasets and published exploration wells to map submarine slope failures and mass wasting deposits within the Pliocene-Quaternary succession.
The results show that features of mass failures are widespread along the steep (higher than 10\ub0) slopes of the Ionian margin south of Calabria and within the intra-slope basins of the margin east of Calabria. Seafloor features range from small-scale features (hundreds of meters in extent), mainly located on the canyon headwalls and sidewalls, to larger slides ( up to 10 km in extent) on open slopes. Subsurface profiles across open slopes and intra-slope basins provide evidence of repeated failures, particularly in the upper Quaternary. The stratigraphic distribution of failures suggests that widespread mass wasting features occur above an unconformity tentatively dated to the Middle Pleistocene (<1 Ma). This unconformity also provides a lower bound for the onset of canyon formation. We infer that the onset of both mass wasting and canyon formation could be a response to the rapid km-scale differential uplift of Calabria over last 1 Ma, which has driven a seaward tilting of the Ionian Calabrian margin
Wild carnivores as source of zoonotic helminths in north-eastern Italy
AbstractTwo hundreds and sixty red foxes, eighteen badgers and eight stone martens from north-eastern Italy were examined for zoonotic parasites by SCT, with particular attention to Trichinella sp. and Echinococcus multilocularis. No adult worms of E. multilocularis were observed in the intestine of red foxes or mustelids. Out of 223 fox faecal samples analysed by a commercial CA-ELISA, 5.8 % was positive to Echinococcus coproantigens. Trichinella sp. was detected by digestion of muscle in 1.2 % of examined foxes (2/172), but not in mustelids (0/11). Toxocara canis, responsible for human toxocarosis, resulted to be common in fox population (48.5 %). This parasite was found both in young (53.3 % of cubs and 61.9 % of sub-adults) and in adult animals (42.7 %). Other zoonotic parasites as Uncinaria stenocephala (52.3 %) and Trichuris vulpis (0.4 %) were detected in fox populations
Properties of Pt Schottky Type Contacts On High-Resistivity CdZnTe Detectors
In this paper we present studies of the I-V characteristics of CdZnTe
detectors with Pt contacts fabricated from high-resistivity single crystals
grown by the high-pressure Brigman process. We have analyzed the experimental
I-V curves using a model that approximates the CZT detector as a system
consisting of a reversed Schottky contact in series with the bulk resistance.
Least square fits to the experimental data yield 0.78-0.79 eV for the Pt-CZT
Schottky barrier height, and <20 V for the voltage required to deplete a 2 mm
thick CZT detector. We demonstrate that at high bias the thermionic current
over the Schottky barrier, the height of which is reduced due to an interfacial
layer between the contact and CZT material, controls the leakage current of the
detectors. In many cases the dark current is not determined by the resistivity
of the bulk material, but rather the properties of the contacts; namely by the
interfacial layer between the contact and CZT material.Comment: 12 pages, 11 figure
Plasmodium falciparum Apicomplexan-Specific Glucosamine-6-Phosphate N-Acetyltransferase Is Key for Amino Sugar Metabolism and Asexual Blood Stage Development
UDP-N-acetylglucosamine (UDP-GlcNAc), the main product of the hexosamine biosynthetic pathway, is an important metabolite in protozoan parasites since its sugar moiety is incorporated into glycosylphosphatidylinositol (GPI) glycolipids and N- and O-linked glycans. Apicomplexan parasites have a hexosamine pathway comparable to other eukaryotic organisms, with the exception of the glucosamine-phosphate N-acetyltransferase (GNA1) enzymatic step that has an independent evolutionary origin and significant differences from nonapicomplexan GNA1s. By using conditional genetic engineering, we demonstrate the requirement of GNA1 for the generation of a pool of UDP-GlcNAc and for the development of intraerythrocytic asexual Plasmodium falciparum parasites. Furthermore, we present the 1.95 A resolution structure of the GNA1 ortholog from Cryptosporidium parvum, an apicomplexan parasite which is a leading cause of diarrhea in developing countries, as a surrogate for P. falciparum GNA1. The indepth analysis of the crystal shows the presence of specific residues relevant for GNA1 enzymatic activity that are further investigated by the creation of site-specific mutants. The experiments reveal distinct features in apicomplexan GNA1 enzymes that could be exploitable for the generation of selective inhibitors against these parasites, by targeting the hexosamine pathway. This work underscores the potential of apicomplexan GNA1 as a drug target against malaria. IMPORTANCE Apicomplexan parasites cause a major burden on global health and economy. The absence of treatments, the emergence of resistances against available therapies, and the parasite''s ability to manipulate host cells and evade immune systems highlight the urgent need to characterize new drug targets to treat infections caused by these parasites. We demonstrate that glucosamine-6-phosphate N-acetyltransferase (GNA1), required for the biosynthesis of UDP-N-acetylglucosamine (UDP-GlcNAc), is essential for P. falciparum asexual blood stage development and that the disruption of the gene encoding this enzyme quickly causes the death of the parasite within a life cycle. The high-resolution crystal structure of the GNA1 ortholog from the apicomplexan parasite C. parvum, used here as a surrogate, highlights significant differences from human GNA1. These divergences can be exploited for the design of specific inhibitors against the malaria parasite
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