226 research outputs found
Social discounting, migration and optimal taxation of savings
We study the problem of optimal inheritance and capital income taxation in an economy with migration. We find that, contrary to previous studies on OLG models, even if the utility function is assumed to be homothetic and separable in consumption and leisure, a non-zero tax result emerges whenever the policy maker attaches weights to the individual utility functions in the social welfare function that are allowed to vary through time, for example, according to the demographic dynamics of the economy. We also perform a welfare analysis of the choice among different social weights: the results depend on several factors, among which the extent of the distortions induced by the tax instruments vis-a`-vis the suboptimality of the market allocation in an OLG economy, deriving from the disconnection among generations
Bioelectrochemical hydrogen production with hydrogenophilic dechlorinating bacteria as electrocatalytic agents
n/
Impact of the COVID-19 Pandemic on Otolaryngology Residency: A Real-Life Experience
The coronavirus disease (COVID-19) pandemic as been rapidly spreading worldwide. In our country, the entire Italian Healthcare System has been forced to adapt to this unprecedented condition in this century. The Head and Neck Department clinical and surgical activity was substantially reduced. In this situation, the Ear, Nose and Throat (ENT) residents in University Hospitals find themselves in an uncertain position; we are physicians, facing a deadly disease about which much remains unknown, but we are also trainees, and there is a high risk for our residency training to be affected. With this Letter, we would like to give a testimony of our experience and give some advices to bridge the training gap
Thalamo-cortical spiking model of incremental learning combining perception, context and NREM-sleep
The brain exhibits capabilities of fast incremental learning from few noisy examples, as well as the ability to associate similar memories in autonomously-created categories and to combine contextual hints with sensory perceptions. Together with sleep, these mechanisms are thought to be key components of many high-level cognitive functions. Yet, little is known about the underlying processes and the specific roles of different brain states. In this work, we exploited the combination of context and perception in a thalamo-cortical model based on a soft winner-take-all circuit of excitatory and inhibitory spiking neurons. After calibrating this model to express awake and deep-sleep states with features comparable with biological measures, we demonstrate the model capability of fast incremental learning from few examples, its resilience when proposed with noisy perceptions and contextual signals, and an improvement in visual classification after sleep due to induced synaptic homeostasis and association of similar memories
The Brain on Low Power Architectures - Efficient Simulation of Cortical Slow Waves and Asynchronous States
Efficient brain simulation is a scientific grand challenge, a
parallel/distributed coding challenge and a source of requirements and
suggestions for future computing architectures. Indeed, the human brain
includes about 10^15 synapses and 10^11 neurons activated at a mean rate of
several Hz. Full brain simulation poses Exascale challenges even if simulated
at the highest abstraction level. The WaveScalES experiment in the Human Brain
Project (HBP) has the goal of matching experimental measures and simulations of
slow waves during deep-sleep and anesthesia and the transition to other brain
states. The focus is the development of dedicated large-scale
parallel/distributed simulation technologies. The ExaNeSt project designs an
ARM-based, low-power HPC architecture scalable to million of cores, developing
a dedicated scalable interconnect system, and SWA/AW simulations are included
among the driving benchmarks. At the joint between both projects is the INFN
proprietary Distributed and Plastic Spiking Neural Networks (DPSNN) simulation
engine. DPSNN can be configured to stress either the networking or the
computation features available on the execution platforms. The simulation
stresses the networking component when the neural net - composed by a
relatively low number of neurons, each one projecting thousands of synapses -
is distributed over a large number of hardware cores. When growing the number
of neurons per core, the computation starts to be the dominating component for
short range connections. This paper reports about preliminary performance
results obtained on an ARM-based HPC prototype developed in the framework of
the ExaNeSt project. Furthermore, a comparison is given of instantaneous power,
total energy consumption, execution time and energetic cost per synaptic event
of SWA/AW DPSNN simulations when executed on either ARM- or Intel-based server
platforms
Prevalence of p53 dysregulations in feline oral squamous cell carcinoma and non-neoplastic oral mucosa
Squamous cell carcinoma is the most common malignant oral tumor in cats. The late presentation is one of the factors contributing to the detrimental prognosis of this disease. The immunohistochemical expression of the p53 tumor suppressor protein has been reported in 24% to 65% of feline oral squamous cell carcinomas, but no study has systematically evaluated in this tumor the presence of p53 encoding gene (TP53) mutations. The aim of this retrospective study was to determine whether p53 immunohistochemistry accurately reflects the mutational status of the TP53 gene in feline oral squamous cell carcinoma. Additionally, the prevalence of p53 dysregulation in feline oral squamous cell carcinoma was compared with that of feline non-neoplastic oral mucosa, in order to investigate the relevance of these dysregulations in cancer development. The association between p53 dysregulations and exposure to environmental tobacco smoke and tumor characteristics was further assessed. Twenty-six incisional biopsies of oral squamous cell carcinomas and 10 cases each of lingual eosinophilic granuloma, chronic gingivostomatitis and normal oral mucosa were included in the study. Eighteen squamous cell carcinomas (69%) expressed p53 and 18 had mutations in exons 5\u20138 of TP53. The agreement between immunohistochemistry and mutation analysis was 77%. None of non-neoplastic oral mucosa samples had a positive immunohistochemical staining, while one case each of eosinophilic granuloma and chronic gingivostomatitis harbored TP53 mutations. Unlike previously hypothesized, p53 dysregulations were not associated with exposure to environmental tobacco smoke. These results suggest an important role of p53 in feline oral tumorigenesis. Additionally, the immunohistochemical detection of p53 expression appears to reflect the presence of TP53 mutations in the majority of cases. It remains to be determined if the screening for p53 dysregulations, alone or in association with other markers, can eventually contribute to the early detection of this devastating disease
The eagle jugular syndrome
The elongation of the styloid process is historically associated with two variants of the Eagle syndrome. The classic one, mainly characterized by pain and dysphagia, and the carotid variant characterized by pain and sometimes by cerebral ischemia. We observed a further variant characterized by a styloid elongation coursing adjacent to the transverse process of C1, causing significant compression of the internal jugular vein
The "Defibrillation Testing, Why Not?" survey. Testing of subcutaneous and transvenous defibrillators in the Italian clinical practice
Background: Defibrillation testing (DT) can be omitted in patients undergoing transvenous implantable cardioverter-defibrillator (T-ICD) implantation, but it is still recommended for patients at risk for a high defibrillation threshold and for ICD generator changes. Moreover, DT is still recommended on implantation of subcutaneous ICD (S-ICD). The aim of the present survey was to analyze the current practice of DT during T-ICD and S-ICD implantations.Methods: In March 2021, an ad hoc questionnaire on the current performance of DT and the standard practice adopted during testing was completed at 72 Italian centers implanting S-ICD and T-ICD.Results: 48 (67%) operators reported never performing DT during de-novo T-ICD implantations, while no operators perform it systematically. The remaining respondents perform it for patients at risk for a high defibrillation threshold. DT is never performed at T-ICD generator change. At the time of de-novo S-ICD implantation, DT is never performed by 9 (13%) operators and performed systematically by 48 (66%). The remaining operators frequently omit DT in patients with more severe systolic dysfunction. DT is not performed at S-ICD generator change by 92% of operators. DT is conducted by delivering a first shock energy of 65 J by 60% of operators, while the remaining 40% test lower energy values.Conclusions: In current clinical practice, most operators omit DT at T-ICD implantation, even when still recommended in the guidelines. DT is also frequently omitted at S-ICD implantation, and a wide variability exists among operators in the procedures followed during DT
Two-Level Corpectomy and Fusion vs. Three-Level Anterior Cervical Discectomy and Fusion without Plating: Long-Term Clinical and Radiological Outcomes in a Multicentric Retrospective Analysis
Background: Anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) represent effective alternatives in the management of multilevel cervical spondylotic myelopathy (CSM). A consensus on which of these techniques should be used is still missing. Methods: The databases of three centers were reviewed (January 2011-December 2018) for patients with three-level CSM, who underwent three-level ACDF without plating or two-level ACCF with expandable cage (VBRC) or mesh (VBRM). Demographic data, surgical strategy, complications, and implant failure were analyzed. The Neck Disability Index (NDI), the Visual Analog Scale (VAS), and the cervical lordosis were compared between the two techniques at 3 and 12 months. Logistic regression analyses investigated independent factors influencing clinical and radiological outcomes. Results: Twenty-one and twenty-two patients were included in the ACDF and ACCF groups, respectively. The median follow-up was 18 months. ACDFs were associated with better clinical outcomes at 12 months (NDI: 8.3% vs. 19.3%, p < 0.001; VAS: 1.3 vs. 2.6, p = 0.004), but with an increased risk of loss of lordosis correction & GE; 1 & DEG; (OR = 4.5; p = 0.05). A higher complication rate in the ACDF group (33.3% vs. 9.1%; p = 0.05) was recorded, but it negatively influenced only short-term clinical outcomes. ACCFs with VBRC were associated with a higher risk of major complications but ensured better 12-month lordosis correction (p = 0.002). No significant differences in intraoperative blood loss were noted. Conclusions: Three-level ACDF without plating was associated with better clinical outcomes than two-level ACCF despite worse losses in lordosis correction, which is ideal for fragile patients without retrovertebral compressions. In multilevel CSM, the relationship between the degree of lordosis correction and clinical outcome advantages still needs to be investigated
- …