5,833 research outputs found
Cooling of young neutron stars in GRB associated to Supernova
Recent observations of the late (-- s) emission of supernovae
(SNe) associated to GRBs (GRB-SN) show a distinctive emission in the X-ray
regime consistent with temperatures -- K. Similar features have
been also observed in the two Type Ic SNe SN 2002ap and SN 1994I that are not
associated to GRBs. We advance the possibility that the late X-ray emission
observed in GRB-SN and in isolated SN is associated to a hot neutron star (NS)
just formed in the SN event, here defined as a neo-NS. We discuss the thermal
evolution of neo-NS in the age regime that spans from minute (just
after the proto-NS phase) up to ages <10-100 yr. We examine the key factor
governing the neo-NS cooling emphasizing on the neutrino emission. A
phenomenological heating source and new boundary conditions are introduced to
mimic the high-temperature atmosphere of young NSs. We match the neo-NS
luminosity to the late X-ray emission of the GRB-SN events URCA-1 in
GRB980425-SN1998bw, URCA-2 in GRB030329-SN2003dh, and URCA-3 in
GRB031203-SN2003lw. By calibrating our additional heating source at early times
to -- erg/g/s, we find a striking agreement of the
luminosity obtained from the cooling of neo-NSs with the late
(-- s) X-ray emission observed in GRB-SN. It is therefore
appropriate to revise the boundary conditions used in the cooling theory of
NSs, to match the proper conditions of the atmosphere at young ages. Additional
heating processes that are still not studied within this context, such as e+e-
pair creation by overcritical fields and nuclear fusion and fission energy
release, might also take place under such conditions and deserve further
analysis. Observation of GRB-SN has shown the possibility of witnessing the
thermal evolution of neo-NSs. A new campaign of dedicated observations is
recommended both of GRB-SN and of isolated Type Ic SN.Comment: Version to be published by Astronomy & Astrophysics. Abstract reduced
with respect to the one to be published in A&A due to arXiv system constraint
of 300 word
Special Issue: Advances in SARS-CoV-2 Infection
Since the beginning of the pandemic, and particularly during the first and second waves, the goal of this Special Issue has been to highlight the crucial aspects of SARS- CoV-2 and the disease in light of the new knowledge that was emerging. A total of 15 manuscripts have been published in this Special Issue. These papers provided insights into epidemiology, pathogenesis, epigenetics COVID-19 emergencies in hospital settings, advanced diagnosis, vaccination, and SARS-CoV-2 infection in the experimental setting. The high scientific rigor, originality, and, for some of them, the high number of citations obtained, are well evident
Bone Involvement in Systemic Lupus Erythematosus
Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by a wide variability of clinical manifestations due to the potential involvement of several tissues and internal organs, with a relapsing and remitting course. Dysregulation of innate and adaptive immune systems, due to genetic, hormonal and environmental factors, may be responsible for a broad spectrum of clinical manifestations, affecting quality of life, morbidity and mortality. Bone involvement represents one of the most common cause of morbidity and disability in SLE. Particularly, an increased incidence of osteoporosis, avascular necrosis of bone and osteomyelitis has been observed in SLE patients compared to the general population. Moreover, due to the improvement in diagnosis and therapy, the survival of SLE patient has improved, increasing long-term morbidities, including osteoporosis and related fractures. This review aims to highlight bone manifestations in SLE patients, deepening underlying etiopathogenetic mechanisms, diagnostic tools and available treatment
Anti-cyclic-citrullinated-protein-antibodies in psoriatic arthritis patients: how autoimmune dysregulation could affect clinical characteristics, retention rate of methotrexate monotherapy and first line biotechnological drug survival. A single center retrospective study
Aim: Occasional findings of anti-cyclic-citrullinated-protein-antibodies (anti-CCP) were rarely observed in psoriatic arthritis (PsA). The aim of our study is to evaluate whether the presence of anti-CCP can determine different clinical subsets and influence methotrexate monotherapy survival, and biotechnological drug retention rate. Methods: We conducted a retrospective study on PsA patients. All patients were required to fulfill the CASPAR criteria for PsA, and to present juxta-articular osteo-proliferative signs at X-ray. The exclusion criteria were age less than 18 years old, satisfaction of rheumatoid arthritis classification criteria, and seropositivity for rheumatoid factor. Clinical characteristics, anti-CCP titer, drug survival and comorbidities information were recorded for each patient. Statistical significance was set at p ⩽ 0.05. Results: Of 407 patients with PsA screened 113 were recruited. Twelve patients were anti-CCP positive. Methotrexate monotherapy survival was shorter in patients with anti-CCP (150 ± 48.3 weeks versus 535.3 ± 65.3 weeks; p = 0.026) [discontinuation risk hazard ratio (HR) = 2.389, 95% confidence interval (CI) 1.043, 5.473; p = 0.039] than those without. Significant shorter survival of first-line biotechnological drugs (b-DMARDs) was observed in the anti-CCP positive group than in that without (102.05 ± 24.4 weeks versus 271.6 ± 41.7 weeks; p = 0.005) with higher discontinuation risk (HR = 3.230, 95% CI 1.299, 8.028; p = 0.012). A significant higher rate of multi-failure (more than second-line b-DMARDs) was found in anti-CCP positive patients than in those without (50% versus 14%, p = 0.035). Conclusion: Anti-CCP in PsA could be suggestive of more severe disease, with worse drug survival of both methotrexate monotherapy and first-line b-DMARDs, and higher chance to be b-DMARDs multi-failure. So, they can be considered for more intensive clinical management of these patients
Virtual actuator-based FTC for LPV systems with saturating actuators and FDI delays
The main contribution of this paper consists in solving the problem of fault tolerant control (FTC) for linear parameter varying (LPV) systems subject to actuator saturation and fault detection and isolation (FDI) delays. The FTC is based on virtual actuators that reconfigure the faulty plant to maintain the stability and to avoid the saturation of the actuators. On the other hand, a design methodology that provides the nominal output-feedback controller, which maximizes the tolerated delay between the fault occurrence and its isolation, is developed. The design process consists in finding the optimal feasible solution to a finite set of linear matrix inequalities (LMIs). Finally, an example is used to illustrate the theoretical results.Peer ReviewedPostprint (author's final draft
Manajemen Pendidikan
Perubahan sosial dan globalisasi telah menimbulkan ekonomi pengetahuan baru di mana isu esensialnya adalah apa yang kita sebut sebagai pengetahuan dalam sebuah organisasi, bagaimana pengetahuan ini ditransmisikan dan dipelihara, siapa yang memilikinya, dan bagaimana ini menjadi milik bersama. Demikianlah, globalisasi mempengaruhi segi-segi ekonomi, politik, kultural, teknis, dan sosial di semua negara, yang secara tak terelakkan membawa pada ketidakpastian (uncertainty); misalnya, dalam pasar kerja yang sedang berubah.
Di sinilah manajemen pendidikan, sebagai suatu ilmu khusus yang menangani pengorganisasian pendidikan, perlu memberikan jawaban pada ketidakpastian tadi dalam rangka perannya sebagai perangkat untuk memerangi eksklusi sosial. Manajemen pendidikan dituntut untuk memposisikan kembali (repositioning) lembaga pendidikan untuk memenuhi keperluan abad ‘super-kompleks.
Non-pharmacological treatments for pediatric refractory epilepsies
Introduction: Antiseizure medications (ASMs) are the primary treatment option for epilepsies of wide etiologies, however, about 10–20% of children do not gain sustained seizure control and in this case, it is worth investigating ‘alternative’ therapeutic approaches aside from ASMs. Nowadays, non-pharmacological strategies for epilepsy treatment encompass dietary interventions, neurostimulation-based techniques, and biobehavioral approaches. Areas covered: A search on PubMed database was conducted. Experimental and clinical studies, as well as meta-analysis and structured reviews on the latest non-pharmacological treatments for drug-resistant epilepsy (DRE) in children, were included. Special attention is given to the efficacy and tolerability outcomes, trying to infer the role novel approaches may have in the future. Expert opinion: The large heterogeneity of primary clinical outcomes and the unavoidable subjective response of each patient to treatments prevents Researchers from the identification of a single, reliable, approach to treat DRE. The understanding of fine pathophysiologic processes is giving the way to the use of alternative therapies, such as the well-known ketogenic diet, in a ‘personalized’ view of treatment. The goal is to apply the non-pharmacological treatment most suitable for the patients sake
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