5,005 research outputs found
On the ultraviolet behaviour of quantum fields over noncommutative manifolds
By exploiting the relation between Fredholm modules and the
Segal-Shale-Stinespring version of canonical quantization, and taking as
starting point the first-quantized fields described by Connes' axioms for
noncommutative spin geometries, a Hamiltonian framework for fermion quantum
fields over noncommutative manifolds is introduced. We analyze the ultraviolet
behaviour of second-quantized fields over noncommutative 3-tori, and discuss
what behaviour should be expected on other noncommutative spin manifolds.Comment: 10 pages, RevTeX version, a few references adde
No more time to stay âsingleâ in the detection of Anisakis pegreffii, A. simplex (s. s.) and hybridization events between them: a multi-marker nuclear genotyping approach
A multi-marker nuclear genotyping approach was performed on larval and adult specimens of Anisakis spp. (N = 689) collected from fish and cetaceans in allopatric and sympatric areas of the two species Anisakis pegreffii and Anisakis simplex
(s. s.), in order to: (1) identify specimens belonging to the parental taxa by using nuclear markers (allozymes loci) and sequence analysis of a new diagnostic nuclear DNA locus (i.e. partial sequence of the EF1 뱉1 nDNA region) and (2) recognize hybrid categories. According to the Bayesian clustering algorithms, based on those markers, most of the individuals
(N = 678) were identified as the parental species [i.e. A. pegreffii or A. simplex (s. s.)], whereas a smaller portion (N = 11)
were recognized as F1 hybrids. Discordant results were obtained when using the polymerase chain reactionârestriction
fragment length polymorphisms (PCRâRFLPs) of the internal transcribed spacer (ITS) ribosomal DNA (rDNA) on
the same specimens, which indicated the occurrence of a large number of âhybridsâ both in sympatry and allopatry.
These findings raise the question of possible misidentification of specimens belonging to the two parental Anisakis and
their hybrid categories derived from the application of that single marker (i.e. PCRâRFLPs analysis of the ITS of
rDNA). Finally, Bayesian clustering, using allozymes and EF1 뱉1 nDNA markers, has demonstrated that hybridization
between A. pegreffii and A. simplex (s. s.) is a contemporary phenomenon in sympatric areas, while no introgressive hybridization takes place between the two species
Osteomalacia and vitamin D status: a clinical update 2020
Historically, rickets and osteomalacia have been synonymous with vitamin D deficiency dating back to the 17th century. The term osteomalacia, which literally means soft bone, was traditionally applied to characteristic radiologically or histologically documented skeletal disease and not just to clinical or biochemical abnormalities. Osteomalacia results from impaired mineralization of bone that can manifest in several types, which differ from one another by the relationships of osteoid (ie, unmineralized bone matrix) thickness both with osteoid surface and mineral apposition rate. Osteomalacia related to vitamin D deficiency evolves in three stages. The initial stage is characterized by normal serum levels of calcium and phosphate and elevated alkaline phosphatase, PTH, and 1,25-dihydroxyvitamin D [1,25(OH)2D]âthe latter a consequence of increased PTH. In the second stage, serum calcium and often phosphate levels usually decline, and both serum PTH and alkaline phosphatase values increase further. However, serum 1,25(OH)2D returns to normal or low values depending on the concentration of its substrate, 25-hydroxyvitamin D (25OHD; the best available index of vitamin D nutrition) and the degree of PTH elevation. In the final stage, hypocalcemia and hypophosphatemia are invariably low with further exacerbation of secondary hyperparathyroidism. The exact,or even an approximate, prevalence of osteomalacia caused by vitamin D deficiency is difficult to estimate, most likely it is underrecognized or misdiagnosed as osteoporosis. Signs and symptoms include diffuse bone, muscle weakness, and characteristic fracture pattern, often referred to as pseudofractures, involving ribs, scapulae, pubic rami, proximal femurs, and codfish-type vertebrae. The goal of therapy of vitamin D-deficiency osteomalacia is to alleviate symptoms, promote fracture healing, restore bone strength, and improve quality of life while correcting biochemical abnormalities. There is a need for better understanding of the epidemiology of osteomalacia. Simplified tools validated by concurrent bone histology should be developed to help clinicians promptly diagnose osteomalacia. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research
Role of ventricular tachycardia ablation in arrhythmogenic right ventricular cardiomyopathy
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by progressive fibro-fatty replacement of the myocardium that represents the substrate for recurrent sustained ventricular tachycardia (VT). These arrhythmias characterize the clinical course of a sizeable proportion of patients and have significant implications for their quality of life and long-term prognosis. Antiarrhythmic drugs are often poorly tolerated and usually provide incomplete control of arrhythmia relapses. Catheter ablation is a potentially effective strategy to treat frequent VT episodes and ICD shocks in ARVC patients. The aims of this review are to discuss the electrophysiological and electroanatomic substrates of ventricular tachycardia in patients with ARVC and to analyze the role of catheter ablation in their management with particular reference to selection of patients, technical issues, potential complications and outcomes
Effect of concentration on the physical properties of cashew juice.
Thermal conductivity, thermal diffusivity, density and viscosity of cashew juice were measured at 30 oC for soluble solids content ranging from 5.5 to 25 oBrix. Thermal conductivity and diffusivity were determined using a linear hest source probe. Both properties were found to decrease with the increase of soluble solids content, while density and viscosity increased. Empirical models were fitted to the experimental data for each property and the accuracy of those models was checked
Decoding of Multiple Wrist and Hand Movements Using a Transient EMG Classifier
The design of prosthetic controllers by means of neurophysiological signals still poses a crucial challenge to bioengineers. State of the art of electromyographic (EMG) continuous pattern recognition controllers rely on the questionable assumption that repeated muscular contractions produce repeatable patterns of steady-state EMG signals. Conversely, we propose an algorithm that decodes wrist and hand movements by processing the signals that immediately follow the onset of contraction (i.e., the \textit {transient} EMG). We collected EMG data from the forearms of 14 non-amputee and 5 transradial amputee participants while they performed wrist flexion/extension, pronation/supination, and four hand grasps (power, lateral, bi-digital, open). We firstly identified the combination of wrist and hand movements that yielded the best control performance for the same participant (intra-subject classification). Then, we assessed the ability of our algorithm to classify participant data that were not included in the training set (cross-subject classification). Our controller achieved a median accuracy of 96% with non-amputees, while it achieved heterogeneous outcomes with amputees, with a median accuracy of 89%. Importantly, for each amputee, it produced at least one \textit {acceptable} combination of wrist-hand movements (i.e., with accuracy >85%). Regarding the cross-subject classifier, while our algorithm obtained promising results with non-amputees (accuracy up to 80%), they were not as good with amputees (accuracy up to 35%), possibly suggesting further assessments with domain-adaptation strategies. In general, our offline outcomes, together with a preliminary online assessment, support the hypothesis that the transient EMG decoding could represent a viable pattern recognition strategy, encouraging further online assessments
Reduced Self-Awareness Following a Combined Polar and Paramedian Bilateral Thalamic Infarction. A Possible Relationship With SARS-CoV-2 Risk of Contagion?
Estudo reológico de polpa de caju em diferentes concentraçÔes.
Neste estudo foi avaliado o comportamento reolĂłgico de polpa de caju em diferentes concentraçÔes (5,5 a 25,0°Brix) na temperatura de 30°C. Os resultados indicaram um aumento da viscosidade com o aumento da concentração. A polpa de caju teve o comportamento de um fluido nĂŁo Newtoniano com caracterĂsticas pseudoplĂĄsticas. Palavras-chave: Anacardium occidentale L., reologia, viscosidade
A case-control study of cancers of the gastric cardia in Italy.
In a case-control study of gastric cancer (GC) in high-risk and low-risk areas in Italy, 923 GCs were reviewed by one pathologist and classified according to anatomic site. There were 68 (7.4%) cancers occurring in the gastric cardia. Compared to other GCs, cardia cancer tended to occur more often in males (sex ratio 2.8 vs 1.7) and as intestinal or unclassified histologic types. Nutritional factors for cardia tumours resembled those of other GCs, showing inverse associations with the consumption of raw vegetables, citrus and other fresh fruit, and ascorbic acid, and positive associations with the intake of traditional soups and meat, protein and cholesterol, and preference for salty foods. Cigarette smoking and wine consumption were unrelated to cardia cancer risk, and there was only a weak association with total alcohol intake. Cardia tumours showed a greater familial occurrence of GC than did other sites, with a 7-fold increase in risk for those reporting two first-degree relatives with GC. The authors discuss these findings in view of the rising incidence of adenocarcinomas of the cardia and lower oesophagus that has been reported in some western countries
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