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New techniques are advancing the frontier of high-pressure physics beyond 1 terapascal, leading to new discoveries and offering stringent tests for condensed-matter theory and advanced numerical methods. However, the ability to absolutely determine the pressure state remains challenging, and well-calibrated pressure-density reference materials are required. We conducted shockless dynamic compression experiments at the National Ignition Facility and the Z machine to obtain quasi-absolute, high-precision, pressure-density equation-of-state data for gold and platinum. We derived two experimentally constrained pressure standards to terapascal conditions. Establishing accurate experimental determinations of extreme pressure will facilitate better connections between experiments and theory, paving the way toward improving our understanding of material response to these extreme conditions.
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Ramp compression along a low-temperature adiabat offers a unique avenue to explore the physical properties of materials at the highest densities of their solid form, a region inaccessible by single shock compression. Using the National Ignition Facility and OMEGA laser facilities, copper samples were ramp compressed to peak pressures of 2.30 TPa and densities of nearly 30 g/cc, providing fundamental information regarding the compressibility and phase of copper at pressures more than 5 times greater than previously explored. Through x-ray diffraction measurements, we find that the ambient face-centered-cubic structure is preserved up to 1.15 TPa. The ramp compression equation-of-state measurements shows that there are no discontinuities in sound velocities up to 2.30 TPa, suggesting this phase is likely stable up to the peak pressures measured, as predicted by first-principal calculations. The high precision of these quasiabsolute measurements enables us to provide essential benchmarks for advanced computational studies on the behavior of dense monoatomic materials under extreme conditions that constitute a stringent test for solid-state quantum theory. We find that both density-functional theory and the stabilized jellium model, which assumes that the ionic structure can be replaced by an ionic charge distribution by constant positive-charge background, reproduces our data well. Further, our data could serve to establish new international secondary scales of pressure in the terapascal range that is becoming experimentally accessible with advanced static and dynamic compression techniques.
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We combined laser shock compression with in situ x-ray diffraction to probe the crystallographic state of gold (Au) on its principal shock Hugoniot. Au has long been recognized as an important calibration standard in diamond anvil cell experiments due to the stability of its face-centered cubic (fcc) structure to extremely high pressures (P >600 GPa at 300 K). This is in contrast to density functional theory and first principles calculations of the high-pressure phases of Au that predict a variety of fcc-like structures with different stacking arrangements at intermediate pressures. In this Letter, we probe high-pressure and high-temperature conditions on the shock Hugoniot and observe fcc Au at 169 GPa and the first evidence of body-centered cubic (bcc) Au at 223 GPa. Upon further compression, the bcc phase is observed in coexistence with liquid scattering as the Hugoniot crosses the Au melt curve before 322 GPa. The results suggest a triple point on the Au phase diagram that lies very close to the principal shock Hugoniot near â¼220 GPa.
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We present laser-driven shock compression experiments on cryogenic liquid deuterium to 550 GPa along the principal Hugoniot and reflected-shock data up to 1 TPa. High-precision interferometric Doppler velocimetry and impedance-matching analysis were used to determine the compression accurately enough to reveal a significant difference as compared to state-of-the-art ab initio calculations and thus, no single equation of state model fully matches the principal Hugoniot of deuterium over the observed pressure range. In the molecular-to-atomic transition pressure range, models based on density functional theory calculations predict the maximum compression accurately. However, beyond 250 GPa along the principal Hugoniot, first-principles models exhibit a stiffer response than the experimental data. Similarly, above 500 GPa the reflected shock data show 5%-7% higher compression than predicted by all current models.
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INTRODUCTION: Few clinical studies have analyzed the utility of distal interlocking screws in stable and unstable intertrochanteric fractures treated with intramedullary devices. We performed a prospective analysis comparing short unlocked versus short dynamic and short static distal locked intramedullary nails. MATERIALS AND METHODS: Nine level-II trauma centres were involved in the study. 240 patients over the age of 65 with a stable (AO/OTA 31-A1) or unstable intertrochanteric fracture (AO/OTA 31-A2) were prospectively investigated. The same type of nail was used in every patient. Patients were randomly divided into 3 groups according to the type of distal locking used. Intra-operative variables were examined and patients were followed clinically and radiographically at 1, 3, 6, 12 months postoperatively. All complications were recorded. RESULTS: A total of 212 patients completed 1 year of follow-up visits. In the Unlocking Group (UG) the operation time, blood loss, fluoroscopy time, total length of incision were significantly decreased compared to both the Dynamic Group (DG) and the Static Group (SG) (p < 0.05). Conversely, no reliable differences in intraoperative variables were noted between the Dynamic Group and the Static Group (p > 0.05). In terms of time of fracture union we found no differences among the three Groups (p > 0.05). Moreover, no cases of limb shortening >1 cm or varus collapse were detected in any group. The 3 Groups were similar in terms of HHS, SF-12 and Barthel index results at 1-year follow-up (p > 0.05). Finally, no significant differences were demonstrated across the three Groups in terms of major complications. CONCLUSIONS: This clinical study further confirms the hypothesis that short intramedullary nails do not need to be locked for stable and unstable intertrochanteric fractures.
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Pinos Ortopédicos , Fixação Intramedular de Fraturas , Consolidação da Fratura/fisiologia , Fraturas do Quadril/cirurgia , Instabilidade Articular/cirurgia , Idoso , Feminino , Fluoroscopia , Seguimentos , Fixação Intramedular de Fraturas/instrumentação , Fixação Intramedular de Fraturas/métodos , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/fisiopatologia , Humanos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/fisiopatologia , Masculino , Estudos Prospectivos , Amplitude de Movimento Articular , Centros de Traumatologia , Resultado do TratamentoRESUMO
INTRODUCTION: Acetabulum periprosthetic fractures are rare, but are increasing, due to increase in high-energy trauma and a decrease in mortality index. Reconstruction of an acetabular fracture, in the presence of hip arthroplasty can be very complex and represents a real challenge for orthopedic surgeon. Aim of this multicentric study is to classify periprosthetic acetabulum fractures and to propose a treatment algorithm. MATERIALS AND METHODS: 24 cases of acetabular periprosthetic fracture were treated surgically from 01.01.2010 to 31.04.2017 in three different hospitals; 4 males and 20 females, average age 76 years (range 56-90 years). TREATMENT: 4 cases treated conservatively, 8 cases ORIF, 2 cases treated with acetabular ring and screws, 9 cases ORIF and acetabular cup revision, 1 implant removal without revision. RESULTS: All cases were reviewed at minimum 12 months follow-up. In 22 cases, there was no need for new surgical procedures and radiographically all implants appeared stable and with good bone integration. In a case of a type 1b fracture, a dislocation of prosthetic implant was observed after 3 months. In a case prosthesis was explanted and it was not possible to perform a revision. DISCUSSION AND CONCLUSIONS: Fracture classification systems must facilitate communication between surgeons and encourage documentation and research. However, they should also have prognostic value, so from them should come directly a treatment algorithm. In our experience, most important factors as prognostic and therapeutic predictors were: implant stability and timing of fracture: intraoperative or postoperative. In postoperative fractures CT is mandatory to evaluate cup mobilization and fracture patterns. Our classification proposal is simple and easy to remember for daily use. From it is derived a simple treatment plan.
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Acetábulo/lesões , Artroplastia de Quadril , Consolidação da Fratura/fisiologia , Instabilidade Articular/classificação , Fraturas Periprotéticas/classificação , Complicações Pós-Operatórias/classificação , Reoperação/métodos , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Artroplastia de Quadril/métodos , Feminino , Seguimentos , Prótese de Quadril , Humanos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fraturas Periprotéticas/diagnóstico por imagem , Fraturas Periprotéticas/fisiopatologia , Fraturas Periprotéticas/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Falha de PróteseRESUMO
INTRODUCTION: acetabular fractures are difficult to treat with often an unsatisfactory results for patients. The aim of this study is to investigate about the health-related quality-of-life outcome of patients with a traumatic acetabular fracture, as recorded at least 24 months after their surgery. METHODS: a cohort of patients underwent a dedicated acetabular surgical reconstruction for a pelvic trauma between November 2011 and May 2016, were enrolled to investigate, at least two years after injury, their midterm quality of life; SF-36 and LiSat-11 were used. RESULTS: 35 patients were enrolled but only 28 patients were revisited, 20 males (714%) and 8 females (286%) with a mean age of 43 years (19-73). The most common cause was motor vehicle accident (655%). Lower score after trauma are reported in both tests, SF-36 and LiSat 11, for all items. DISCUSSION: comparing the SF-36 score in the Italian normative sample with our SF-36 score before the trauma there is no statistically significant difference (p = 0.1661) underlining how the patients before the trauma were healthy and in good health. Both scores, SF-36 and LiSat-11, before and after trauma are statistically different with respectively p = 0,0002 and p = 0,049 which proves the lower quality of life after trauma in comparison to their life before trauma. CONCLUSIONS: Although the treatment protocols of acetabular fractures have greatly improved over the years, these continue to have disabling consequences that hardly allow to recover a good quality of life two years after the trauma.
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Acetábulo/lesões , Consolidação da Fratura/fisiologia , Fraturas Ósseas/cirurgia , Qualidade de Vida , Recuperação de Função Fisiológica/fisiologia , Adulto , Fatores Etários , Idoso , Avaliação da Deficiência , Feminino , Seguimentos , Fraturas Ósseas/fisiopatologia , Fraturas Ósseas/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Retrospectivos , Fatores de Tempo , Adulto JovemRESUMO
Thermal conductivity is one of the most crucial physical properties of matter when it comes to understanding heat transport, hydrodynamic evolution, and energy balance in systems ranging from astrophysical objects to fusion plasmas. In the warm dense matter regime, experimental data are very scarce so that many theoretical models remain untested. Here we present the first thermal conductivity measurements of aluminum at 0.5-2.7 g/cc and 2-10 eV, using a recently developed platform of differential heating. A temperature gradient is induced in a Au/Al dual-layer target by proton heating, and subsequent heat flow from the hotter Au to the Al rear surface is detected by two simultaneous time-resolved diagnostics. A systematic data set allows for constraining both thermal conductivity and equation-of-state models. Simulations using Purgatorio model or Sesame S27314 for Al thermal conductivity and LEOS for Au/Al release equation-of-state show good agreement with data after 15 ps. Discrepancy still exists at early time 0-15 ps, likely due to non-equilibrium conditions.
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Tuning the energy of an x-ray probe to an absorption line or edge can provide material-specific measurements that are particularly useful for interfaces. Simulated hard x-ray images above the Fe K-edge are presented to examine ion diffusion across an interface between Fe2O3 and SiO2 aerogel foam materials. The simulations demonstrate the feasibility of such a technique for measurements of density scale lengths near the interface with submicron spatial resolution. A proof-of-principle experiment is designed and performed at the Linac coherent light source facility. Preliminary data show the change of the interface after shock compression and heating with simultaneous fluorescence spectra for temperature determination. The results provide the first demonstration of using x-ray imaging at an absorption edge as a diagnostic to detect ultrafast phenomena for interface physics in high-energy-density systems.
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We investigated whether a proximal femoral nail can be implanted without a distal locking screw in AO/OTA 31-A1 and 31-A2 pertrochanteric stable femur fractures. A multicentre, randomised study was conducted in six level-two trauma centres in our area (Puglia, Italy). A total of 333 patients received their allocated intervention (162 in the locking group [LG] and 171 in the unlocking group [UG]) and 266 patients were included in the final analysis at 1year. Our data showed no statistically significant difference between the two groups at 1-year follow-up for ability to walk, SF-36 questionnaire results, residual pain (visual analogue scale [VAS] score) and level of overall satisfaction. There were also no statistically significant differences between groups for mortality and length of hospital stay. Conversely, the UG was associated with shorter operation and fluoroscopy times, shorter surgical incision length, and less blood loss and residual thigh pain. Pertrochanteric stable fractures (31-A1, 31-A2) can be treated successfully with intramedullary nails without distal locking, reducing patient and clinical personnel radiation exposure and sanitary costs (surgery time and screws costs).
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Pinos Ortopédicos , Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas , Fraturas por Osteoporose/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Centros de Traumatologia , Idoso , Idoso de 80 Anos ou mais , Parafusos Ósseos , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/fisiopatologia , Fluoroscopia , Fixação Intramedular de Fraturas/métodos , Consolidação da Fratura , Humanos , Itália/epidemiologia , Masculino , Duração da Cirurgia , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/fisiopatologia , Satisfação do Paciente , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Resultado do TratamentoRESUMO
INTRODUCTION: Rotator cuff tears commonly necessitate surgical repair; however, the optimal technique for repair continues to be investigated. Recently, double-row repairs have been considered an alternative to single-row repair, allowing a greater coverage area for healing and a possibly stronger repair. AIM: We performed a study to compare single-row repair and suture-bridge (SB) technique (a TOE technique) in terms of the recovery of the strength and functional outcome. MATERIAL AND METHOD: The purpose of the retrospective study was to compare 44 patients treated for a rotator cuff repair with the single-row (24) or suture-bridge techniques (20). At 24-month FU, there were not statistically significant differences for the UCLA score, Individual Constant Score, pain, ROM, and strength on the treated and contra-lateral arm. Comparing the mean values of the differences in strength obtained between the treated arm and the contra lateral in each group, the final results appeared significantly different in favor of SB (p = 0.03). CONCLUSION: Patients treated with DR could expect to regain the same strength of the contra-lateral side, while patients treated with SR could expect globally good results, overall in terms of pain relief and functionality, but lower strength.
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Artroscopia/métodos , Lesões do Manguito Rotador/cirurgia , Técnicas de Sutura/instrumentação , Suturas , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Lesões do Manguito Rotador/diagnóstico , Fatores de Tempo , Resultado do Tratamento , CicatrizaçãoRESUMO
In this work, we describe the clinical and instrumental results of our experience, the first reported in the literature, of the administration of teriparatide to treat severe osteoporosis secondary to epidermolysis bullosa. Already after 2 months of therapy, the patient, a 20-year-old affected by a recessive form of epidermolysis bullosa dystrophica, had less pain and a functional recovery resulting in an improved autonomy; a satisfactory increase in the densitometric values was documented.
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Conservadores da Densidade Óssea/uso terapêutico , Osteoporose/tratamento farmacológico , Teriparatida/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Epidermólise Bolhosa Distrófica/complicações , Feminino , Humanos , Osteoporose/complicações , Osteoporose/reabilitação , Adulto JovemRESUMO
El aneurisma arteriosclerótico aislado de la arteria femoral superficial es una patología inusual. Presentamos el caso de un paciente de 89 años que acude a nuestro hospital por una masa pulsátil de muslo derecho. Se demostró la presencia de un aneurisma a través del diagnóstico por imágenes y procedimos a su resección quirúrgica. Realizamos una revisión de la literatura de esta patología poco frecuente.
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Humanos , Masculino , Idoso , Aneurisma/cirurgia , Aneurisma/complicações , Artéria Femoral/cirurgia , Artéria Femoral/patologia , Fatores Etários , Aneurisma/epidemiologia , Aneurisma/etiologia , Procedimentos Cirúrgicos Vasculares/métodos , Fatores SexuaisRESUMO
The paper describes a measurement device for obtaining the kinematic characterisation and isometric loading of ankle joints under different working conditions. Non-invasive, in vivo experiments can be conducted with this experimental apparatus, the potential of which could be usefully exploited in basic biomedical research, prosthesis design, clinical applications, sports medicine and rehabilitation. The device determines the 3D movement of the foot with respect to the shank and evaluates the torques and moments around the three articular axes in relation to any desired angular position of the ankle complex. When integrated with superficial electromyographic techniques and electrical stimulation, it allows the assessment of the functionality of the lower leg in both mechanical and myo-electrical terms. The paper reports the main mechanical and electronic features of the device (high linearity; maximum moment ranges +/- 300 Nm for flexion-extension, +/- 35 Nm for both pronation-supination and internal-external rotation; angular ranges: +/- 100 degrees of dorsi-plantar flexion, +/- 50 degrees of internal-external rotation and prono-supination; linear ranges: +/- 25 mm along each axis). Results from a healthy volunteer, under voluntary or stimulated conditions, helped in testing its operatability, reliability, robustness, repeatability and effectiveness. Preliminary simplified protocols have been also applied to 20 healthy volunteers, and the main results were 80.8 +/- 11.9 degrees of internalexternal rotation, 46.2 +/- 9.1 degrees of prono-supination and 74.6 +/- 13.1 degrees of flexion-extension. Torques and moments were normalised with respect to a body mass index of 30. The maximum plantar flexion moment (57.5 + 21.3 Nm) was measured with the foot at 150 of dorsal flexion; the maximum dorsal flexion moment (50.2 + 20.3 Nm) was measured with the foot at 150 of plantar flexion.
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Articulação do Tornozelo/fisiologia , Eletromiografia , Desenho de Equipamento , Humanos , Contração Isométrica , Movimento , Músculo Esquelético/fisiologia , Torque , Suporte de CargaRESUMO
Mutations in the caveolin-3 (CAV3) gene are associated with autosomal dominant limb-girdle muscular dystrophy (LGMD1C). The authors report a novel sporadic mutation in the CAV3 gene in two unrelated children with persistent elevated levels of serum creatine kinase (hyperCKemia) without muscle weakness. Immunohistochemistry and quantitative immunoblot analysis of caveolin-3 showed reduced expression of the protein in muscle fibers. Our data indicate that a partial caveolin-3 deficiency should be considered in the differential diagnosis of idiopathic hyperCKemia.
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Caveolinas , Creatina Quinase/sangue , Glicoproteínas/deficiência , Glicoproteínas/genética , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Distrofias Musculares/genética , Mutação/genética , Sequência de Aminoácidos , Caveolina 3 , Pré-Escolar , Humanos , Imuno-Histoquímica , Masculino , Dados de Sequência Molecular , Distrofias Musculares/patologiaRESUMO
We report a case of polyneuropathy caused by primary Epstein Barr virus (EBV) infection in a 57-year-old patient. The primary EBV infection was confirmed by serology tests and EBNA (Epstein-Barr nuclear antigen) seroconversion. The main clinical sign was a highly painful subacute, bilateral lumbar radiculoplexopathy with amyotrophy which responded to corticosteroids and complement treatment within a few months. The association of left facial paralysis, neurophysiological signs of polyradiculopathy and elevated protein levels in the cerebrospinal fluid demonstrate the variability of peripheral neurological involvement in the same subject with EBV infection. This case also demonstrates the poorly limits of dysimmune polyneuropathies, including lumbar radiculoplexopathy which can be considered as an exceptional variant.
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Infecções por Herpesviridae/complicações , Herpesvirus Humano 4 , Plexo Lombossacral , Polirradiculoneuropatia/virologia , Infecções Tumorais por Vírus/complicações , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/imunologiaRESUMO
From January 1991 to December 1993 409 post-menopausal women were observed at the Center for the Study of Climateric Disorders of the Department of Obstetrics and Gynecology of the University of L'Aquila. The aim of the study was to evaluate the incidence of gynecologic neoplasm among this group of women. A total of 48 women at risk for malignant tumors were detected. The relationship between the climateric age and the oncologic risk is discussed.