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1.
Phys Rev Lett ; 132(15): 154101, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682971

RESUMO

We report direct observations of surface waves from a stereo camera system along with concurrent measurements of wind speed during an expedition across the Southern Ocean in the austral winter aboard the South African icebreaker S.A. Agulhas II. Records include water surface elevation across a range of wave conditions spanning from early stages of wave growth to full development. We give experimental evidence of rogue seas, i.e., sea states characterized by heavy tails of the probability density function well beyond the expectation based on bound mode theory. These conditions emerge during wave growth, where strong wind forcing and high nonlinearity drive wave dynamics. Quasiresonance wave-wave interactions, which are known to sustain the generation of large amplitude rogue waves, capture this behavior. Wave statistics return to normality as the wind forcing ceases and waves switch to a full developed condition.

2.
Philos Trans A Math Phys Eng Sci ; 380(2235): 20210255, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36088929

RESUMO

A summary is given on the utility of laboratory experiments for gaining understanding of wave attenuation in the marginal ice zone, as a complement to field observations, theory and numerical models. It is noted that most results to date are for regular incident waves, which, combined with the highly nonlinear wave-floe interaction phenomena observed and measured during experimental tests, implies that the attenuation of regular waves cannot necessarily be used to infer the attenuation of irregular waves. Two experiments are revisited in which irregular wave tests were conducted but not previously reported, one involving a single floe and the other a large number of floes, and the transmission coefficients for the irregular and regular wave tests are compared. The transmission spectra derived from the irregular wave tests agree with the regular wave data but are overpredicted by linear models due to nonlinear dissipative processes, regardless of floe configuration. This article is part of the theme issue 'Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks'.

3.
Hand Surg Rehabil ; 41(5): 606-612, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988912

RESUMO

We report results with the INCA® distal scaphoid pole resurfacing implant anchored within the scaphoid for isolated scaphotrapeziotrapezoid osteoarthritis. Thirty-five implants in 27 patients (mean age, 69 years) were retrospectively included with a minimum follow-up of 2 years. Outcome criteria were pain (VAS), PROMs (QuickDASH, PRWE and MMWS), wrist motion, pinch and grip strength, and radiographic assessment. The average follow-up was 4.6 years. There was a significant improvement in pain, PROMs, grip and pinch strength. Radial deviation and wrist extension showed slight but significant postoperative decrease (-4° for both). Dorsal intercalated segment instability (DISI) was significantly improved postoperatively (7 cases versus 21 preoperatively). There were 2 cases of implant loosening (6%) within the first 10 months: 1 keel malpositioning and 1 insufficient postoperative immobilization. These findings suggest that the INCA® implant is an effective and reliable medium-term solution for isolated scaphotrapeziotrapezoid osteoarthritis. By restoring scaphoid length and gliding on the trapeziotrapezoid surface, the implant contributes to restoring normal bone alignment of the wrist.


Assuntos
Prótese Articular , Osteoartrite , Idoso , Seguimentos , Humanos , Osteoartrite/cirurgia , Dor , Estudos Retrospectivos
4.
Hand Surg Rehabil ; 40S: S106-S116, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33540123

RESUMO

In 1970, Jean-Yves de la Caffinière developed the first trapeziometacarpal (TMC) joint prosthesis, a ball-and-socket design based on hip replacement implants. From 1970 to 1990, the first generation of cemented prostheses was developed. At that time, trapeziectomy, with tendon interposition or suspension arthroplasty, and Swanson silastic spacers remained the most widely used surgical procedures for thumb basal joint arthritis. From 1990 to 2010, a second generation of cementless prostheses was developed. The third generation was introduced after 2010 and consisted of dual mobility prostheses. In 2020, TMC arthroplasty (simple or dual mobility) is a reliable option in thumb basal joint arthritis with an implant survival rate of 90% at 10 years of follow-up, while providing pain relief and restoring strength and mobility. Restoration of the thumb's length corrects most thumb Z-deformities, so the TMC joint prosthesis may be a viable alternative surgical solution to trapeziectomy, which remains the gold standard in English-speaking countries. Moreover, trapeziectomy after failed TMC arthroplasty provides outcomes equivalent to those of primary trapeziectomy.


Assuntos
Artroplastia de Substituição , Prótese Articular , Osteoartrite , Humanos , Osteoartrite/cirurgia , Tendões/cirurgia , Polegar/cirurgia
5.
Food Res Int ; 119: 236-243, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884654

RESUMO

Phenols from olive mill waste water (OMWW) represent valuable functional ingredients. The negative impact on sensory quality limits their use in functional food formulations. Chemical interactions phenols/biopolymers and their consequences on bioactivity in plant-base foods have been widely investigated, but no studies to date have explored the variation of bitterness, astringency and pungency induced by OMWW phenols as a function of the food composition. The aim of the paper was to profile the sensory and chemical properties of phenols from OMWW in plant-base foods varied in their macro-composition. Four phenol concentrations were selected (0.44, 1.00, 2.25, 5.06 g/kg) to induce significant variations of bitterness, sourness, astringency and pungency in three plant-base food: proteins/neutral pH - bean purée (BP), starch/neutral pH - potato purée (PP), fiber/low pH - tomato juice (TJ). The macro-composition affected the amount of the phenols recovered from functionalized food. The highest recovery was from TJ and the lowest from BP. Two groups of 29 and 27 subjects, trained to general Labelled Magnitude Scale and target sensations, participated in the evaluation of psychophysical curves of OMWW phenols and of functionalized plant-base foods, respectively. Target sensations were affected by the food macro-composition. Bitterness increased with phenol concentration in all foods. Astringency and sourness slightly increased with concentration, reaching the weak-moderate intensity at the highest phenol concentration in PP and TJ only. Pungency was suppressed in BP and perceived at weak-moderate intensity in PP and TJ sample at the highest phenol concentration. Proteins/neutral pH plant-food (BP) resulted more appropriate to counteract the impact of added phenol on negative sensory properties thus allowing to optimize the balance between health and sensory properties.


Assuntos
Olea , Fenóis/análise , Extratos Vegetais/análise , Águas Residuárias/química , Adulto , Feminino , Análise de Alimentos , Manipulação de Alimentos , Alimento Funcional/análise , Humanos , Concentração de Íons de Hidrogênio , Resíduos Industriais , Masculino , Plantas Comestíveis , Paladar , Adulto Jovem
6.
Hand Surg Rehabil ; 38(1): 71-73, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30401614

RESUMO

We report the case of a 28-year-old man with a septic forearm non-union treated with minocycline for 3 months. At the time of reconstructive surgery, the radius and ulna were entirely black. Surgical debridement until bleeding of both bone extremities resulted in a 5-cm defect that was filled with a cement spacer. Histology confirmed poorly vascularized bone with focal areas of acute inflammatory infiltrate at the non-union sites (highly suggestive of infection) and normal structure of the remaining diaphyseal bones, although black in color. Reconstruction with free vascularized fibula transfer was successful leading to complete bone healing. An incidental finding of minocycline-induced black bone discoloration should not change the surgeon's decision because there is no evidence of adverse effects on bone healing in the literature. Surgery can be performed safely at sites of minocycline-induced black bone pigmentation.


Assuntos
Antibacterianos/efeitos adversos , Minociclina/efeitos adversos , Transtornos da Pigmentação/induzido quimicamente , Rádio (Anatomia)/efeitos dos fármacos , Ulna/efeitos dos fármacos , Adulto , Antibacterianos/administração & dosagem , Fixação Intramedular de Fraturas/efeitos adversos , Fraturas não Consolidadas/cirurgia , Humanos , Masculino , Minociclina/administração & dosagem , Complicações Pós-Operatórias , Rádio (Anatomia)/patologia , Fraturas do Rádio/cirurgia , Reoperação , Infecção da Ferida Cirúrgica/tratamento farmacológico , Ulna/patologia , Fraturas da Ulna/cirurgia
7.
J Vet Cardiol ; 22: 96-105, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30554843

RESUMO

INTRODUCTION: This report provides clinical examples of upper rate behavior in dogs with dual-chamber pacemakers, with suggestions for programming alterations to avoid detrimental upper rate behavior. ANIMALS: Six dogs with dual-chamber pacemakers displaying upper rate behavior at upper atrial tracking rates. METHODS: Medical records of dogs with dual-chamber pacemakers with evidence of upper rate behavior were reviewed retrospectively from two institutions. Two of the six dogs were followed prospectively, and 24 h Holter monitors were placed to evaluate upper rate behavior correlated to programming settings. RESULTS: Pacemaker Wenckebach or 2:1 atrioventricular block was documented in four of six dogs, and automatic mode switch was documented in two of six dogs. Twenty-four-hour Holter monitors placed on two dogs after pacemaker optimization documented a pacemaker Wenckebach window at increased atrial rates with neither dog reaching their respective 2:1 block point throughout the recording period. CONCLUSIONS: Clinicians who implant dual-chamber pacemakers should be aware of upper rate behavior in animal species with high heart rates. Optimal programming of dual-chamber pacemakers can be achieved by selecting programmed timing intervals to limit deleterious upper rate behavior and create a more physiologic ventricular response at maximum tracking rates.


Assuntos
Bradicardia/veterinária , Estimulação Cardíaca Artificial/veterinária , Marca-Passo Artificial/veterinária , Animais , Bloqueio Atrioventricular/veterinária , Bradicardia/terapia , Estimulação Cardíaca Artificial/métodos , Cães , Desenho de Equipamento/veterinária , Feminino , Frequência Cardíaca , Masculino
8.
Phys Rev E ; 97(1-1): 012208, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29448489

RESUMO

Rogue waves are extreme and rare fluctuations of the wave field that have been discussed in many physical systems. Their presence substantially influences the statistical properties of a partially coherent wave field, i.e., a wave field characterized by a finite band spectrum with random Fourier phases. Their understanding is fundamental for the design of ships and offshore platforms. In many meteorological conditions waves in the ocean are characterized by the so-called Joint North Sea Wave Project (JONSWAP) spectrum. Here we compare two unique experimental results: the first one has been performed in a 270 m wave tank and the other in optical fibers. In both cases, waves characterized by a JONSWAP spectrum and random Fourier phases have been launched at the input of the experimental device. The quantitative comparison, based on an appropriate scaling of the two experiments, shows a very good agreement between the statistics in hydrodynamics and optics. Spontaneous emergence of heavy tails in the probability density function of the wave amplitude is observed in both systems. The results demonstrate the universal features of rogue waves and provide a fundamental and explicit bridge between two important fields of research. Numerical simulations are also compared with experimental results.

9.
Biomed Res Int ; 2017: 9164156, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29209631

RESUMO

OBJECTIVE: Sinus floor elevation with lateral approach is probably the most frequently performed reconstructive procedure to rehabilitate posterior maxilla when a bone deficiency is present. Different graft materials have been proposed and tested, often with high clinical performances and predictable results. Histological analysis is required when evaluating new materials. We investigated human biopsies retrieved after sinus floor elevation procedure by histomorphometric evaluation to test the performance of an equine-derived bone grafting material. STUDY DESIGN: Seventeen consecutive patients were enrolled and sinus lift surgeries were performed using an equine bone graft. Six months after surgery, at implant placement, bone samples were collected. Histomorphometry analysis was carried out on decalcified samples. RESULTS: All surgeries were uneventful and no additional grafting was required prior to implant insertion. Forty percent of new bone formation was detected, which represented the most abundant tissue retrieved, followed by the residual graft material (33%) and fibrous tissue (27%). A significant reduction in particles size demonstrates a remodeling activity of the graft material. CONCLUSION: Within the limitations of this study, this equine-derived bone graft proved to be an effective material to induce new bone formation in the sinus floor elevation procedure.


Assuntos
Transplante Ósseo/métodos , Implantação Dentária Endóssea/métodos , Seio Maxilar/cirurgia , Levantamento do Assoalho do Seio Maxilar/métodos , Adolescente , Adulto , Animais , Feminino , Cavalos/anatomia & histologia , Humanos , Masculino , Maxila/fisiopatologia , Maxila/cirurgia , Seio Maxilar/fisiopatologia , Osteogênese/fisiologia , Transplantes/crescimento & desenvolvimento , Transplantes/transplante , Adulto Jovem
10.
J Biol Regul Homeost Agents ; 31(3): 579-587, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28952290

RESUMO

Rough titanium surfaces enhance cell response to activation of Wnt canonical signalling, a pathway required for osteoblast differentiation. The present study investigated the effects of GSK3ß-inhibitors SB216763 and SB415286 on osteoblastic differentiation on titanium surfaces with different topography and wettability. Osteoblastic MC3T3 cells were plated on smooth (Pickled), sand-blasted/acid-etched (SLA) or hyper hydrophilic SLA (modSLA) titanium discs and transfected with a reporter vector sys-tem for Wnt canonical signalling. Cells were also seeded in the presence or in the absence of GSK3b-inhibitors SB216763 or SB415286 and their viability, morphology and the expression of Wnt target and osteoblast specific genes was assessed by Real Time PCR. Inhibitors altered cell morphology and mostly reduced cell viability at high concentration. SB415286 markedly increased the expression of ALP in MC3T3 cells on rough surfaces at the concentration of 100 nM before decreasing its expression at higher concentrations. OCN expression was unaffected. Increasing concentrations of SB216763 increased the expression of ALP in MC3T3 cells on rough surfaces but OCN expression was not changed at any con-centration. SB216763 and SB415286 inhibitors should be further investigated as potential tools to improve cell differentiation on titanium surfaces for endosseous implants.


Assuntos
Aminofenóis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Indóis/farmacologia , Maleimidas/farmacologia , Osteoblastos/enzimologia , Titânio/química , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Osteoblastos/citologia , Propriedades de Superfície
11.
Orthop Traumatol Surg Res ; 103(6): 829-833, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28652054

RESUMO

INTRODUCTION: Coracoid bone graft transfer has become the gold standard in patients with recurrent anterior shoulder instability associated with bony defect. Several studies have shown that the main stabilizing component of this procedure is the sling effect by the conjoint tendon and the lower portion of subscapularis (SS). The purpose of this study was to determine whether a larger SS volume below the bone block was correlated to greater postoperative shoulder stability. MATERIALS AND METHODS: This prospective study included a cohort of patients who underwent open coracoid bone graft transfer for post-traumatic recurrent anterior shoulder instability. Forty patients were reviewed at 2 years with a clinical and CT scan evaluation. A correlation analysis assessed the relation between the SS volume index (ratio of SS volume below the bone block to volume over the bone block) and Rowe and Walch-Duplay instability scores. RESULTS: There exists a positive and significant correlation between SS volume index and postoperative Rowe score, r=0.37 (P=0.03). The same trend was observed for Walch-Duplay score without statistical significance. A larger inferior SS volume did not result in a limitation of external rotation, greater fatty infiltration, or malposition of the coracoid graft. CONCLUSION: A larger SS volume below the bone block is related to greater postoperative shoulder stability. We recommend performing the split in the middle of the SS or higher instead of the junction of the superior two-thirds and inferior one-third as usually reported. LEVEL OF EVIDENCE: III, prospective study.


Assuntos
Transplante Ósseo/métodos , Processo Coracoide/transplante , Instabilidade Articular/cirurgia , Osteotomia , Manguito Rotador/cirurgia , Luxação do Ombro/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Manguito Rotador/anatomia & histologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
12.
Hand Surg Rehabil ; 36(3): 181-185, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28465193

RESUMO

The midcarpal joint can be classified into two anatomical types - Viegas type I and Viegas type II - based on the absence or presence of a medial facet for the hamate on the lunate (lunohamate facet). Type I is associated with a round capitate shape, which theoretically allows better congruence with the lunate fossa of the distal radius following proximal row carpectomy (PRC). This morphological feature has never been considered as a predictive factor of clinical outcome for this surgical procedure. This study aimed to compare the clinical and radiological outcomes of the two Viegas types following PRC. A retrospective single-center study was carried out on patients who underwent PRC for wrist osteoarthritis. Minimum follow-up was 2 years. Lunate type was determined based on preoperative CT arthrography. The clinical evaluation included range of motion (ROM) and strength as well as the functional DASH, Mayo Wrist scores and a VAS for pain. The outcome of radiocapitate osteoarthritis was assessed on plain radiographs. Forty patients were reviewed with a mean follow-up of 57 months. Twenty-one Viegas type I and 19 Viegas type II were identified on preoperative CT arthrography. The etiologies included 23 SLAC wrists (12 Viegas type I, 11 type II), 8 SNAC wrists (4 Viegas type I, 4 type II), 6 cases of Kienböck's disease (3 type IIIa, 3 type IIIb with 3 Viegas type I and 3 type II), 1 Preiser's disease and 2 cases of transscaphoid perilunate dislocation of the carpus. Patients with a Viegas type I lunate had significantly greater flexion-extension ROM: 83.5° vs. 71° (P=0.04) and radial deviation: 12° vs. 7° (P=0.013) than those with Viegas type II. However, three cases of complex regional pain syndrome (CRPS) were reported in the Viegas type II group vs. zero in the Viegas type I group. There were no differences between the two groups in terms of strength, functional scores or VAS pain. The outcome of radiocapitate osteoarthritis was similar in both groups. Considering the number of CRPS cases in the Viegas type II group and similar functional results in both groups, the worse outcomes of the Viegas type II patients in terms of ROM cannot be considered as clinically relevant. This comparative study does not provide a reasonable basis for concluding that Viegas type I patients are better candidates for PRC than Viegas type II patients.


Assuntos
Ossos do Carpo/diagnóstico por imagem , Ossos do Carpo/cirurgia , Articulações do Carpo/diagnóstico por imagem , Osteoartrite/cirurgia , Articulação do Punho/cirurgia , Articulações do Carpo/cirurgia , Avaliação da Deficiência , Feminino , Seguimentos , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico por imagem , Osteoartrite/fisiopatologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Escala Visual Analógica , Articulação do Punho/diagnóstico por imagem , Articulação do Punho/fisiopatologia
13.
Phys Rev Lett ; 118(14): 144503, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28430520

RESUMO

We investigate experimentally the statistical properties of a wind-generated wave field and the spontaneous formation of rogue waves in an annular flume. Unlike many experiments on rogue waves where waves are mechanically generated, here the wave field is forced naturally by wind as it is in the ocean. What is unique about the present experiment is that the annular geometry of the tank makes waves propagating circularly in an unlimited-fetch condition. Within this peculiar framework, we discuss the temporal evolution of the statistical properties of the surface elevation. We show that rogue waves and heavy-tail statistics may develop naturally during the growth of the waves just before the wave height reaches a stationary condition. Our results shed new light on the formation of rogue waves in a natural environment.

14.
Hand Surg Rehabil ; 36(2): 141-145, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28325429

RESUMO

Rupture of the collateral ligaments in the metacarpophalangeal (MCP) joint of a finger is less common than in the thumb. Literature about these lesions is sparse but the number of chronic injuries reported underlies the number of cases overlooked by physicians at the first visit. A Stener-like lesion is characterized by interposition of the extensor hood or the sagittal band between the torn collateral ligament of the MCP joint of a finger and its insertion. It was originally described as interposition of the adductor aponeurosis of the thumb. We present the first case of a Stener-like lesion in ruptured radial collateral ligaments of the MCP joint of two adjacent fingers.


Assuntos
Ligamentos Colaterais/diagnóstico por imagem , Ligamentos Colaterais/lesões , Articulação Metacarpofalângica/lesões , Acidentes por Quedas , Ligamentos Colaterais/cirurgia , Humanos , Masculino , Articulação Metacarpofalângica/cirurgia , Pessoa de Meia-Idade , Ruptura/cirurgia , Âncoras de Sutura
15.
Artigo em Inglês | MEDLINE | ID: mdl-23767480

RESUMO

We show experimentally that a stable wave propagating into a region characterized by an opposite current may become modulationally unstable. Experiments have been performed in two independent wave tank facilities; both of them are equipped with a wavemaker and a pump for generating a current propagating in the opposite direction with respect to the waves. The experimental results support a recent conjecture based on a current-modified nonlinear Schrödinger equation which establishes that rogue waves can be triggered by a nonhomogeneous current characterized by a negative horizontal velocity gradient.


Assuntos
Modelos Teóricos , Reologia/métodos , Movimentos da Água , Água/química , Simulação por Computador , Movimento (Física)
16.
Phys Rev Lett ; 102(11): 114502, 2009 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-19392204

RESUMO

We discuss two independent, large scale experiments performed in two wave basins of different dimensions in which the statistics of the surface wave elevation are addressed. Both facilities are equipped with a wave maker capable of generating waves with prescribed frequency and directional properties. The experimental results show that the probability of the formation of large amplitude waves strongly depends on the directional properties of the waves. Sea states characterized by long-crested and steep waves are more likely to be populated by freak waves with respect to those characterized by a large directional spreading.

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