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1.
J Craniofac Surg ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861339

RESUMEN

Literature describes variable rates of diplopia of associated with zygomatic maxillary complex (ZMC) fractures (6% to 40%). The aim of this study was to retrospectively assess the prevalence of diplopia in ZMC fracture patients, the usefulness of the orthoptic evaluation compared with the clinical finger-tracking examination, and to seek possible relations of this symptom with clinical parameters. Data of patients attending the Maxillofacial Surgery Units of the University of Messina and University of Naples "Federico II", between January 2012 and December 2022 were retrieved. Statistical analysis of positive versus negative diplopia at both the clinical examination and the orthoptic evaluation and subgroup analysis were performed. 320 patients were included in the analysis. 50 (15.6%) patients reported diplopia at the clinical examination, whereas 70 (21.9%) resulted positive at the orthoptic evaluation. Statistical analysis for every determinant and subgroup did not show statistical significance (P>0.05). Performing routine preoperative orthoptic evaluation allowed an increase of 6.3% in positive reports. Although it seems that no basic clinical parameter can predict diplopia, results suggest that the orthoptic evaluation is superior in the assessment of this symptom. Clinical analysis was shown to be a moderate/low efficient test and should not be used as a decisional standard.

2.
Sci Rep ; 14(1): 11638, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773255

RESUMEN

Is Stochastic Gradient Descent (SGD) substantially different from Metropolis Monte Carlo dynamics? This is a fundamental question at the time of understanding the most used training algorithm in the field of Machine Learning, but it received no answer until now. Here we show that in discrete optimization and inference problems, the dynamics of an SGD-like algorithm resemble very closely that of Metropolis Monte Carlo with a properly chosen temperature, which depends on the mini-batch size. This quantitative matching holds both at equilibrium and in the out-of-equilibrium regime, despite the two algorithms having fundamental differences (e.g. SGD does not satisfy detailed balance). Such equivalence allows us to use results about performances and limits of Monte Carlo algorithms to optimize the mini-batch size in the SGD-like algorithm and make it efficient at recovering the signal in hard inference problems.

3.
Science ; 383(6686): 1005-1009, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38422141

RESUMEN

How turbulent convective fluctuations organize to form larger-scale structures in planetary atmospheres remains a question that eludes quantitative answers. The assumption that this process is the result of an inverse cascade was suggested half a century ago in two-dimensional fluids, but its applicability to atmospheric and oceanic flows remains heavily debated, hampering our understanding of the energy balance in planetary systems. We show using direct numerical simulations with spatial resolutions of 122882 × 384 points that rotating and stratified flows can support a bidirectional cascade of energy, in three dimensions, with a ratio of Rossby to Froude numbers comparable to that of Earth's atmosphere. Our results establish that, in dry atmospheres, spontaneous order can arise through an inverse cascade to the largest spatial scales.

4.
Sci Rep ; 13(1): 3671, 2023 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-36871049

RESUMEN

Finding a Maximum Clique is a classic property test from graph theory; find any one of the largest complete subgraphs in an Erdös-Rényi G(N, p) random graph. We use Maximum Clique to explore the structure of the problem as a function of N, the graph size, and K, the clique size sought. It displays a complex phase boundary, a staircase of steps at each of which [Formula: see text] and [Formula: see text], the maximum size of a clique that can be found, increases by 1. Each of its boundaries has a finite width, and these widths allow local algorithms to find cliques beyond the limits defined by the study of infinite systems. We explore the performance of a number of extensions of traditional fast local algorithms, and find that much of the "hard" space remains accessible at finite N. The "hidden clique" problem embeds a clique somewhat larger than those which occur naturally in a G(N, p) random graph. Since such a clique is unique, we find that local searches which stop early, once evidence for the hidden clique is found, may outperform the best message passing or spectral algorithms.

5.
Sci Adv ; 8(41): eabq2566, 2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36223461

RESUMEN

The ocean's turbulent energy cycle has a paradox; large-scale eddies under the control of Earth's rotation transfer kinetic energy (KE) to larger scales via an inverse cascade, while a transfer to smaller scales is needed for dissipation. It has been hypothesized, using simulations, that fronts, waves, and other turbulent structures can produce a forward cascade of KE toward dissipation scales. However, this forward cascade and its coexistence with the inverse cascade have never been observed. Here, we present the first evidence of a dual KE cascade in the ocean by analyzing in situ velocity measurements from surface drifters. Our results show that KE is injected at two dominant scales and transferred to both large and small scales, with the downscale flux dominating at scales smaller than ∼1 to 10 km. The cascade rates are modulated seasonally, with stronger KE injection and downscale transfer during winter.

6.
J Craniofac Surg ; 33(7): e771-e776, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36201694

RESUMEN

Although events such as tooth extraction and oral surgery were considered for a while the sole triggering factor for Medication-Related Osteonecrosis of the Jaw (MRONJ), it is still unclear if trigger events may be precipitating factors that accelerate the onset of the disease that would have possibly occurred anyway. Therefore, this research aimed to retrospectively analyze MRONJ cases diagnosed in our tertiary referral hospital during the last 14 years, focusing on the onset of the disease, potential trigger events, and countermeasures to update the knowledge on their pathogenesis. An audit of patients diagnosed with MRONJ attending our department from 2008 to 2021was performed. χ2 test and Fisher exact test were employed to assess the relationship between the medications used and trigger events; χ2 test was also used to assess any relationship between MRONJ localization and drug, drug class, trigger, or trigger type. Seventy-six patients' records were identified. Fifty-two records were selected for analysis. Trigger events for the onset of the disease were found in 35 cases (67.3%). χ2 test showed a correlation between the drug used and trigger event occurrence (P=0.045) confirmed by Fisher exact test (P=0.34). Visual histogram analysis showed positive correlation when Alendronate (12 cases, 85.7%), Zoledronate (12 cases, 75%), and Risedronate (2 cases, 100%) were administered. Subgroup analysis per underlying disease, showed a significant correlation between the drug used and trigger event occurrence in the osteoporosis group (χ2 test, P=0.021; Fisher exact test, P=0.009).


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos , Conservadores de la Densidad Ósea , Alendronato , Osteonecrosis de los Maxilares Asociada a Difosfonatos/epidemiología , Osteonecrosis de los Maxilares Asociada a Difosfonatos/etiología , Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Humanos , Factores Desencadenantes , Estudios Retrospectivos , Ácido Risedrónico/efectos adversos , Ácido Zoledrónico
7.
Phys Rev Lett ; 122(3): 035102, 2019 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-30735422

RESUMEN

The description of the local turbulent energy transfer and the high-resolution ion distributions measured by the Magnetospheric Multiscale mission together provide a formidable tool to explore the cross-scale connection between the fluid-scale energy cascade and plasma processes at subion scales. When the small-scale energy transfer is dominated by Alfvénic, correlated velocity, and magnetic field fluctuations, beams of accelerated particles are more likely observed. Here, for the first time, we report observations suggesting the nonlinear wave-particle interaction as one possible mechanism for the energy dissipation in space plasmas.

8.
Nat Commun ; 7: 12996, 2016 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-27694952

RESUMEN

Discrete combinatorial optimization has a central role in many scientific disciplines, however, for hard problems we lack linear time algorithms that would allow us to solve very large instances. Moreover, it is still unclear what are the key features that make a discrete combinatorial optimization problem hard to solve. Here we study random K-satisfiability problems with K=3,4, which are known to be very hard close to the SAT-UNSAT threshold, where problems stop having solutions. We show that the backtracking survey propagation algorithm, in a time practically linear in the problem size, is able to find solutions very close to the threshold, in a region unreachable by any other algorithm. All solutions found have no frozen variables, thus supporting the conjecture that only unfrozen solutions can be found in linear time, and that a problem becomes impossible to solve in linear time when all solutions contain frozen variables.

9.
Phys Rev E ; 93(6): 062147, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27415248

RESUMEN

We consider coupled diffusions in n-dimensional space and on a compact manifold and the resulting effective advective-diffusive motion on large scales in space. The effective drift (advection) and effective diffusion are determined as a solvability conditions in a multiscale analysis. As an example, we consider coupled diffusions in three-dimensional space and on the group manifold SO(3) of proper rotations, generalizing results obtained by H. Brenner [J. Colloid Interface Sci. 80, 548 (1981)JCISA50021-979710.1016/0021-9797(81)90214-9]. We show in detail how the analysis can be conveniently carried out using local charts and invariance arguments. As a further example, we consider coupled diffusions in two-dimensional complex space and on the group manifold SU(2). We show that although the local operators may be the same as for SO(3), due to the global nature of the solvability conditions the resulting diffusion will differ and generally be more isotropic.

10.
Phys Rev E ; 93(1): 012132, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26871049

RESUMEN

We analyze the translational and rotational motion of an ellipsoidal Brownian particle from the viewpoint of stochastic thermodynamics. The particle's Brownian motion is driven by external forces and torques and takes place in an heterogeneous thermal environment where friction coefficients and (local) temperature depend on space and time. Our analysis of the particle's stochastic thermodynamics is based on the entropy production associated with single particle trajectories. It is motivated by the recent discovery that the overdamped limit of vanishing inertia effects (as compared to viscous fricion) produces a so-called "anomalous" contribution to the entropy production, which has no counterpart in the overdamped approximation, when inertia effects are simply discarded. Here we show that rotational Brownian motion in the overdamped limit generates an additional contribution to the "anomalous" entropy. We calculate its specific form by performing a systematic singular perturbation analysis for the generating function of the entropy production. As a side result, we also obtain the (well-known) equations of motion in the overdamped limit. We furthermore investigate the effects of particle shape and give explicit expressions of the "anomalous entropy" for prolate and oblate spheroids and for near-spherical Brownian particles.


Asunto(s)
Entropía , Modelos Teóricos , Movimiento (Física) , Coloides/química , Procesos Estocásticos
11.
Clin Mol Allergy ; 13(1): 10, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26155196

RESUMEN

BACKGROUND: We designed the PROXIMA study (Patient-Reported Outcomes and Xolair(®) In the Management of Asthma) to determine the proportion of patients with severe asthma sensitive to perennial allergens, and to evaluate asthma control and treatment adherence up to 12 months in patients treated with omalizumab in Italian population. In addition, an ancillary study was designed to explore protein biomarkers and characterize them in relation to severe allergic asthma and treatment effects by proteomic approach. METHODS: PROXIMA is an observational, multicenter, cross-sectional and prospective cohort study conducted at 25 centers in Italy, in outpatient settings. The study consists of two phases: 1) a cross-sectional phase plans to enroll 600 patients with severe allergic asthma, in step 4 therapy as per GINA guidelines, aged ≥18 years, needing a step up in therapy, and 2) a longitudinal phase on patients who will start omalizumab add-on therapy per clinician's judgment at baseline visit (approximately 180-240 patients). The primary variable of the cross-sectional phase is the proportion of patients with severe asthma presenting with perennial form of allergy (skin prick test or in vitro test). The primary variable of longitudinal phase is proportion of patients who achieve disease control (assessed by Asthma Control Questionnaire [ACQ]) with omalizumab at 6 months, and maintain it at 12 months. Secondary variables are patient compliance to omalizumab, patient-reported perception of cognitive and emotional impact of the illness, assessed by Brief Illness Perception Questionnaire (Brief IPQ) and the health related quality of life evaluated by the EuroQoL 5D-3 L (EQ-5D-3 L). Safety endpoints will be recorded during the course of the study. Patients participating in the longitudinal phase will be enrolled for ancillary study if they provide additional informed consent. Protein species in complex mixtures will be identified using innovative MudPIT (Multidimensional Protein Identification Technology) method. CONCLUSIONS: The results of this observational study will provide estimate of patient population allergic to perennial allergens in Italy and information on patient-reported outcomes with omalizumab therapy in a real-world setting. The exploratory proteomic analysis on asthma biomarkers could eventually provide new data to identify responder patients to anti IgE therapy.

13.
Diabetes Care ; 36(10): 2887-94, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23735724

RESUMEN

OBJECTIVE: We aimed to evaluate the added value of intensive self-monitoring of blood glucose (SMBG), structured in timing and frequency, in noninsulin-treated patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: The 12-month, randomized, clinical trial enrolled 1,024 patients with noninsulin-treated type 2 diabetes (median baseline HbA1c, 7.3% [IQR, 6.9-7.8%]) at 39 diabetes clinics in Italy. After standardized education, 501 patients were randomized to intensive structured monitoring (ISM) with 4-point glycemic profiles (fasting, preprandial, 2-h postprandial, and postabsorptive measurements) performed 3 days/week; 523 patients were randomized to active control (AC) with 4-point glycemic profiles performed at baseline and at 6 and 12 months. Two primary end points were tested in hierarchical order: HbA1c change at 12 months and percentage of patients at risk target for low and high blood glucose index. RESULTS: Intent-to-treat analysis showed greater HbA1c reductions over 12 months in ISM (-0.39%) than in AC patients (-0.27%), with a between-group difference of -0.12% (95% CI, -0.210 to -0.024; P=0.013). In the per-protocol analysis, the between-group difference was -0.21% (-0.331 to -0.089; P=0.0007). More ISM than AC patients achieved clinically meaningful reductions in HbA1c (>0.3, >0.4, or >0.5%) at study end (P<0.025). The proportion of patients reaching/maintaining the risk target at month 12 was similar in ISM (74.6%) and AC (70.1%) patients (P=0.131). At visits 2, 3, and 4, diabetes medications were changed more often in ISM than in AC patients (P<0.001). CONCLUSIONS: Use of structured SMBG improves glycemic control and provides guidance in prescribing diabetes medications in patients with relatively well-controlled noninsulin-treated type 2 diabetes.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Adulto , Anciano , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad
14.
Acta Diabetol ; 50(5): 663-72, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22189755

RESUMEN

Self-monitoring of blood glucose (SMBG) is a core component of diabetes management. However, the International Diabetes Federation recommends that SMBG be performed in a structured manner and that the data are accurately interpreted and used to take appropriate therapeutic actions. We designed a study to evaluate the impact of structured SMBG on glycemic control in non-insulin-treated type 2 diabetes (T2DM) patients. The Prospective, Randomized Trial on Intensive SMBG Management Added Value in Non-insulin-Treated T2DM Patients (PRISMA) is a 12-month, prospective, multicenter, open, parallel group, randomized, and controlled trial to evaluate the added value of an intensive, structured SMBG regimen in T2DM patients treated with oral agents and/or diet. One thousand patients (500 per arm) will be enrolled at 39 clinical sites in Italy. Eligible patients will be randomized to the intensive structured monitoring (ISM) group or the active control (AC) group, with a glycosylated hemoglobin (HbA1c) target of <7.0%. Intervention will comprise (1) structured SMBG (4-point daily glucose profiles on 3 days per week [ISM]; discretionary, unstructured SMBG [AC]); (2) comprehensive patient education (both groups); and (3) clinician's adjustment of diabetes medications using an algorithm targeting SMBG levels, HbA1c and hypoglycemia (ISM) or HbA1c and hypoglycemia (AC). The intervention and trial design build upon previous research by emphasizing appropriate and collaborative use of SMBG by both patients and physicians. Utilization of per protocol and intent-to-treat analyses facilitates assessment of the intervention. Inclusion of multiple dependent variables allows us to assess the broader impact of the intervention, including changes in patient and physician attitudes and behaviors.


Asunto(s)
Glucemia/análisis , Diabetes Mellitus Tipo 2/sangre , Educación del Paciente como Asunto/métodos , Adulto , Anciano , Algoritmos , Automonitorización de la Glucosa Sanguínea/instrumentación , Automonitorización de la Glucosa Sanguínea/métodos , Automonitorización de la Glucosa Sanguínea/normas , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/epidemiología , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/administración & dosificación , Italia/epidemiología , Persona de Mediana Edad , Visita a Consultorio Médico
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