873 research outputs found
Ferromagnetic features on zero-bias conductance peaks in ferromagnet/insulator/superconductor junction
We present a formula for tunneling conductance in ballistic
ferromagnet/ferromagnetic insulator/superconductor junctions where the
superconducting state has opposite spin pairing symmetry. The formula can
involve correctly a ferromagnetism has been induced by effective mass
difference between up- and down-spin electrons. Then, this effective mass
mismatch ferromagnet and standard Stoner ferromagnet have been employed in this
paper. As an application of the formulation, we have studied the tunneling
effect for junctions including spin-triplet p-wave superconductor. The
conductace spectra show a clear difference between two ferromagnets depending
upon the way of normalization of the conductance. Especially, a essential
difference is seen in zero-bias conductance peaks reflecting characteristics of
each ferromagnets. From obtained results, it will be suggested that the
measurements of the tunneling conductance in the junction provide us a useful
information about the mechanism of itinerant ferromagnetism in metal.Comment: 8 pages, 8 figures, references added to the first versio
Random Graph-Homomorphisms and Logarithmic Degree
A graph homomorphism between two graphs is a map from the vertex set of one
graph to the vertex set of the other graph, that maps edges to edges. In this
note we study the range of a uniformly chosen homomorphism from a graph G to
the infinite line Z. It is shown that if the maximal degree of G is
`sub-logarithmic', then the range of such a homomorphism is super-constant.
Furthermore, some examples are provided, suggesting that perhaps for graphs
with super-logarithmic degree, the range of a typical homomorphism is bounded.
In particular, a sharp transition is shown for a specific family of graphs
C_{n,k} (which is the tensor product of the n-cycle and a complete graph, with
self-loops, of size k). That is, given any function psi(n) tending to infinity,
the range of a typical homomorphism of C_{n,k} is super-constant for k = 2
log(n) - psi(n), and is 3 for k = 2 log(n) + psi(n)
Collagen induction therapy for the treatment of upper lip wrinkles
Upper lip wrinkles are very common and impair the quality of life of many people due to their perceived unsightly appearance. Several options are available today for their treatment. A new therapeutic option, called collagen induction therapy (CIT), seems to be effective and safe for the treatment of upper lip wrinkles. The aim of this study is to demonstrate the efficacy and safety of CIT in the treatment of upper lip wrinkles. Ten female subjects, aged 50-65 years old, with upper lip wrinkles were enrolled. Each patient was treated with a specific tool in two sessions. Using a digital camera, photographs were taken of all the patients to evaluate the depth of the wrinkles and a silicon-print technique was used to obtain a microrelief impression of the wrinkles. Data of the cutaneous casts were analyzed by computerized image analysis. Analysis of the patients' photographs, supported by the sign test, and of the degree of irregularity of the surface microrelief, supported by Fast Fourier Transform and by wrinkle image processing, showed that, after only two sessions, the wrinkles' severity grade in most patients was greatly reduced. The present study confirms CIT as an effective and safe technique to improve upper lip wrinkles
ACE Gene I/D Polymorphism and Acute Pulmonary Embolism in COVID19 Pneumonia: A Potential Predisposing Role
Most recent studies have stressed a high risk of thromboembolism in patients with SARS-CoV-2 infection, particularly in those with severe COVID-19 pneumonia. Counterbalance between angiotensin-converting-enzyme (ACE) and ACE2 activities in COVID-19 disease may be crucially involved in the thrombo-inflammatory process. Currently, no study has investigated ACE I/D polymorphism involvement in COVID-19 disease complicated by pulmonary embolism, hence the aim of the present pilot study. This is a retrospective, single-center observational case-control study, conducted at the Sub-Intensive Care Unit of A.O.R.N. Ospedali dei Colli, Cotugno Hospital, Naples (Italy). We included 68 subjects with severe/critical COVID-19 pneumonia. COVID-19 patients were divided according to occurrence of PE (PE+, n = 25) or absence of thromboembolic complications (PEâ, n = 43). Assessment of ACE I/D polymorphisms showed a statistically significant difference between PE+ and PEâ patients (p = 0.029). Particularly, prevalence of D/D homozygous polymorphism was significantly higher in PE+ COVID-19 patients than in PEâ (72 vs. 46.5%; p = 0.048), while heterozygote I/D polymorphism was significantly lower expressed in PE+ patients than in PEâ (16 vs. 48.8%; p = 0.009). Computed tomographic pulmonary angiography showed predominantly mono/bilateral sub-segmental embolisms. In conclusion, our findings let us hypothesize a genetic susceptibility to thromboembolism in COVID-19 disease. ACE D/D polymorphism might represent a genetic risk factor, although studies on larger populations are needed
Is the pain just physical? The role of psychological distress, quality of life, and autistic traits in ehlersâdanlos syndrome, an internet-based survey in italy
Background: EhlersâDanlos syndromes (EDS) have been associated with psychological distress, comorbid psychiatric disorders, and worsening in quality of life (QoL). Among the neurodevelopmental disorders, autism spectrum disorders (ASD) have shown the highest rates of co-occurrence with EDS. The reasons for these associations are unknown and a possible role of pain in increasing the risk of psychiatric disorders in EDS has been suggested. However, a detailed picture of an Italian EDS sample is still lacking. Methods: We conducted a web-based survey in a third level center for the diagnosis of EDS in northern Italy, to investigate psychological distress, QoL, and the presence of autistic traits. Furthermore, we correlated the psychometric data with some clinical variables. Results: We observed a high rate of psychological distress with 91% of the responders at high risk of common mental disorders, low QoL, and high prevalence of autistic traits in EDS patients. Specifically, patients lacking a specific genetic test, diagnosed as suspects of EDS appeared to be at greater risk and reported worse psychological QoL. Pain was significantly associated with both psychological distress and worse QoL. Conclusions: Our findings support the need of further research and of a multi-disciplinary approach to EDS including psychological and psychiatric liaison
The progression of hemophilic arthropathy: The role of biomarkers
Background: Hemophilia A and B are X-linked congenital bleeding disorders characterized by recurrent hemarthroses leading to specific changes in the synovium and cartilage, which finally result in the destruction of the joint: this process is called hemophilic arthropathy (HA). This review highlights the most prominent molecular biomarkers found in the literature to discuss their potential use in the clinical practice to monitor bleeding, to assess the progression of the HA and the effectiveness of treatments. Methods: A review of the literature was performed on PubMed and Embase, from 3 to 7 August 2020. Study selection and data extraction were achieved independently by two authors and the following inclusion criteria were determined a priori: English language, available full text and articles published in peer-reviewed journal. In addition, further articles were identified by checking the bibliography of relevant articles and searching for the studies cited in all the articles examined. Results: Eligible studies obtained at the end of the search and screen process were seventy-three (73). Conclusions: Despite the surge of interest in the clinical use of biomarkers, current literature underlines the lack of their standardization and their potential use in the clinical practice preserving the role of physical examination and imaging in early diagnosis
Cardiovascular comorbidities and pharmacological treatments of covid-19 patients not requiring hospitalization
Introduction: The Coronavirus disease 2019 (COVID-19) outbreak is a whole Earth health emergency related to a highly pathogenic human coronavirus responsible for severe acute respiratory syndrome (SARS-CoV-2). Despite the fact that the majority of infected patients were managed in outpatient settings, little is known about the clinical characteristics of COVID-19 patients not requiring hospitalization. The aim of our study was to describe the clinical comorbidity and the pharmacological therapies of COVID-19 patients managed in outpatient settings. Materials and Methods: We performed an observational, retrospective analysis of laboratory-confirmed COVID-19 patients managed in outpatient settings in Naples, Italy between March 9 and May 1, 2020. Data were sourced from the prospectively maintained Health Search (HS)/Thales database, shared by 128 primary care physicians (PCPs) in Naples, Italy. The clinical features and pharmacological therapies of COVID-19 patients not requiring hospitalization and managed in outpatient settings have been described. Results: A total of 351 laboratory-confirmed COVID-19 patients (mean age 54 ± 17 years; 193 males) with outpatient management were evaluated. Hypertension was the most prevalent comorbidity (35%). The distribution of cardiovascular comorbidities showed no gender-related differences. A total of 201 patients (57.3%) were treated with at least one experimental drug for COVID-19. Azithromycin, alone (42.78%) or in combination (27.44%), was the most widely used experimental anti-COVID drug in outpatient settings. Low Molecular Weight Heparin and Cortisone were prescribed in 24.87% and 19.4% of the study population, respectively. At multivariate regression model, diabetes (risk ratio (RR): 3.74; 95% CI 1.05 to 13.34; p = 0.04) and hypertension (RR: 1.69; 95% CI 1.05 to 2.7; p = 0.03) were significantly associated with the experimental anti-COVID drug administration. Moreover, only diabetes (RR: 2.43; 95% CI 1.01 to 5.8; p = 0.03) was significantly associated with heparin administration. Conclusions: Our data show a high prevalence of hypertension, more likely treated with reninâ angiotensinâaldosterone system (RASS) inhibitors, among COVID-19 patients not requiring hospitalization. Experimental COVID-19 therapies have been prescribed to COVID-19 patients considered at risk for increased venous thromboembolism based on concomitant comorbidities, in particular diabetes and hypertension
âIl Corpo Ritrovatoâ: Dermocosmetological Skin Care Project for the Oncologic Patient
Neoplastic disease and its therapeutic options have a huge impact on the patient's quality of life from both the emotional and the working point of view. The project âIl Corpo Ritrovatoâ aims at creating an interdisciplinary network of physicians to improve the quality of life of the oncologic patient, focusing on such important aspects as dermocosmetological skin care but also on the evaluation of new therapeutic and diagnostic algorithms in order to make further progress in the field of prevention
A superconducting-nanowire 3-terminal electronic device
In existing superconducting electronic systems, Josephson junctions play a
central role in processing and transmitting small-amplitude electrical signals.
However, Josephson-junction-based devices have a number of limitations
including: (1) sensitivity to magnetic fields, (2) limited gain, (3) inability
to drive large impedances, and (4) difficulty in controlling the junction
critical current (which depends sensitively on sub-Angstrom-scale thickness
variation of the tunneling barrier). Here we present a nanowire-based
superconducting electronic device, which we call the nanocryotron (nTron), that
does not rely on Josephson junctions and can be patterned from a single thin
film of superconducting material with conventional electron-beam lithography.
The nTron is a 3-terminal, T-shaped planar device with a gain of ~20 that is
capable of driving impedances of more than 100 k{\Omega}, and operates in
typical ambient magnetic fields at temperatures of 4.2K. The device uses a
localized, Joule-heated hotspot formed in the gate to modulate current flow in
a perpendicular superconducting channel. We have characterized the nTron,
matched it to a theoretical framework, and applied it both as a digital logic
element in a half-adder circuit, and as a digital amplifier for superconducting
nanowire single-photon detectors pulses. The nTron has immediate applications
in classical and quantum communications, photon sensing and astronomy, and its
performance characteristics make it compatible with existing superconducting
technologies. Furthermore, because the hotspot effect occurs in all known
superconductors, we expect the design to be extensible to other materials,
providing a path to digital logic, switching, and amplification in
high-temperature superconductors
Adding hydroxyurea in combination with ruxolitinib improves clinical responses in hyperproliferative forms of myelofibrosis
Ruxolitinib, an orally bioavailable and selective inhibitor of Janus kinase 1 (JAK1) and JAK2, significantly reduces splenomegaly and disease-related symptoms in patients with myelofibrosis (MF). However, no clear survival benefit has been demonstrated, which may in part reflect suboptimal drug exposure related to lower dosages needed to minimize hematological toxicity, specifically cytopenias. Furthermore, the optimal management of specific conditions such as leukocytosis or thrombocytosis in patients under ruxolitinib therapy is still undefined. In these cases, combining ruxolitinib with a cytoreductive agent like hydroxyurea might improve hematological response. This observational multi-center study enrolled 20 adult patients with intermediate- or high-risk primary MF, post- polycythemia vera MF, or postessential thrombocythemia MF with hyperproliferative manifestations of the disease and WBC and/or platelet counts not controlled by ruxolitinib therapy. The patients received treatment with a combination of ruxolitinib and hydroxyurea. A clinical response of any type was obtained in 8 patients (40%) during ruxolitinib monotherapy and in 17 patients (85%) during ruxolitinib-hydroxyurea combination (PÂ =Â 0.003). After a median duration of 12.4Â months of combination therapy, 16/20 patients had a hematological response; 14/17 patients who had started combination therapy to control WBC count and 2/3 who started in order to reduce platelets count. The number of patients requiring ruxolitinib dosage reduction or discontinuations was lower during combination therapy and, at the end of follow-up the median ruxolitinib dose was increased in 50% of patients. In conclusion, the combination of hydroxyurea with ruxolitinib yielded a high clinical response rate and increased ruxolitinib exposure in patients with hyperproliferative forms of MF
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