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We present a high precision, self-referencing, common path XUV interferometer setup to produce pairs of spatially separated and independently controllable XUV pulses that are locked in phase and time. The spatial separation is created by introducing two equal but opposite wavefront tilts or using superpositions of orbital angular momentum. In our approach, we can independently control the relative phase/delay of the two optical beams with a resolution of 52 zs (zs = zeptoseconds). In order to explore the level of entanglement between the non-local photons, we compare three different beam modes: Bessel-like, and Gaussian with or without added orbital angular momentum. By reconstructing interference patterns one or two photons at a time we conclude that the beams are not entangled, yet each photon in the attosecond pulse train contains information about the entire spectrum. Our technique generates non-local, quantum equivalent XUV photons with a temporal jitter of 3 zs, just below the Compton unit of time of 8 zs. We argue that this new level of temporal precision will open the door for new dynamical QED tests. We also discuss the potential impact on other areas, such as imaging, measurements of non-locality, and molecular quantum tomography., 11 pages 5 figures and supplemental materials with 12 pages and 7 figures

Objective: Verify interobserver and intraobserver agreement of malignant compressive vertebral fractures (MCVF) diagnosis using magnetic resonance imaging (MRI). Methods: We retrospectively included a lumbar spine MRI of 63 patients with non-traumatic compressive vertebral fracture diagnoses. Each lumbar vertebra was classified as: without fracture, with fracture of benign characteristics, or with fracture of malignant characteristics. Two medical residents in radiology, one musculoskeletal radiologist fellow, one musculoskeletal radiologist, and two spine surgeons evaluated MRI exams, independently and blindly. Each observer performed two readings, with a 15-day interval between evaluations. A simple Kappa coefficient was used to calculate the intra and interobserver agreement. The reference standard classification was based on bone biopsy or clinical, and imaging follow-up of at least two years, for diagnostic performance analysis. Diagnostic performance was assessed by calculating sensitivity, specificity, accuracy, and positive and negative predictive values with a 95% confidence interval (CI). Results: We observed substantial to perfect intraobserver agreement (kappa: 0.80 to 1.00) and substantial interobserver agreement (kappa 0.64 to 0.77). In general, the sensitivity for the detection of MCVF was moderate, except for the second-year radiology resident that achieved a lower sensitivity. The specificity, accuracy, and negative predictive value were high for all observers. Conclusion: MCVF diagnosis using MRI showed substantial interobserver agreement. The second-year medical resident achieved lower sensitivity but high specificity for MCVF. Regarding the seniors, there was no statistical significance between spine surgeons and the musculoskeletal radiologist. Level of Evidence III; Diagnostic. RESUMO Objetivo: Verificar a concordância interobservador e intraobservador no diagnóstico de fraturas vertebrais compressivas malignas (MCVF) por meio de ressonância magnética (MRI). Métodos: Incluiu-se retrospectivamente a ressonância magnética da coluna lombar de 63 pacientes com diagnóstico de fratura vertebral compressiva não traumática. Cada vértebra lombar foi classificada da seguinte forma: sem fratura, com fratura de características benignas ou com fratura de características malignas. Dois médicos residentes em radiologia, um pesquisador radiologista musculoesquelético, um radiologista musculoesquelético e dois cirurgiões da coluna vertebral avaliaram os exames de ressonância magnética, independentemente e cegamente. Cada observador realizou duas leituras, com um intervalo de 15 dias entre as avaliações. O coeficiente Kappa simples foi utilizado para calcular o acordo intra e interobservador. A classificação padrão de referência foi baseada em biópsia óssea ou clínica, e acompanhamento por imagem de pelo menos dois anos, para análise de desempenho diagnóstico. O desempenho diagnóstico foi avaliado através do cálculo de sensibilidade, especificidade, precisão, valores preditivos positivos e negativos com um intervalo de confiança de 95% (IC). Resultados: Foi observada concordância substancial a perfeita intraobservador (kappa: 0,80 a 1,00) e concordância substancial interobservador (kappa 0,64 a 0,77). Em geral, a sensibilidade para a detecção de MCVF foi moderada, exceto para o segundo ano de residência radiológica que alcançou uma sensibilidade menor. A especificidade, precisão e valor preditivo negativo foram altos para todos os observadores. Conclusão: O diagnóstico de MCVF por ressonância magnética mostrou uma concordância substancial entre observadores. O residente médico do segundo ano alcançou uma sensibilidade menor, mas alta especificidade para MCVF. Com relação aos veteranos, não houve significância estatística entre os cirurgiões da coluna vertebral e o radiologista músculo-esquelético. Nível de Evidencia III; Diagnóstico.

Ultra-fast laser pulses have made possible the study of extreme nonlinear processes. Many of these experiments however require a full characterization of the electric field, which typically requires a separate parametric optical process. As the central wavelength range of new sources continues to increase so too does the need for nonlinear crystals suited for characterizing these differing wavelengths. Here we report on the use of polycrystalline Zinc Selenide as a universal nonlinear crystal in the frequency resolved optical gating characterization technique from the near to long-wavelength infrared, capable of phase matching second-harmonic generation and sum-frequency generation over a decade of bandwidth, as well as ultra-broadband pulses, all of which being crystal orientation and input polarization independent. With the majority of ultra-fast laser sources being in this span of wavelengths, this work demonstrates a greatly simplified approach towards ultra-fast pulse characterization in the mid to long-wavelength infrared., 5 pages, 4 figures

Objective To evaluate the impact of the severity of lumbar degenerative disease (LDD) on sagittal spinopelvic alignment. Methods In total, 130 patients (mean age: 57 years; 75% female) with LDD-associated low-back pain were prospectively included. The severity of the LDD was defined by the following findings on anteroposterior and lateral lumbar spine radiographs: osteophytosis; loss of of height of the intervertebral disc; terminal vertebral plate sclerosis; number of affected segments; deformities; and objective instability. The disease was classified as follows: grade 0-absence of signs of LDD in the lumbar spine; grade I - signs of LDD in up to two segments; grade II - three or more segments involved; grade III - association with scoliosis, spondylolisthesis, or laterolisthesis. Spinopelvic radiographic parameters, including pelvic incidence (PI), lumbar lordosis (LL), discrepancy between the PI and LL (PI-LL), pelvic tilt (PT), and sagittal vertical axis (SVA), were analyzed according to the LDD grades. Results The radiographic parameters differed according to the LDD grades; grade-III patients presented higher SVA (p= 0.001) and PT (p= 0.0005) values, denoting greater anterior inclination of the trunk and pelvic retroversion when compared to grade-0 andgrade-I subjects. In addition, grade-III patients had higher PI-LL values, which indicates loss of PI-related lordosis, than grade-I subjects (p= 0.04). Conclusion Patients with more severe LDD tend to present greater spinopelvic sagittal misalignment compared to patients with a milder disease. Resumo Objetivo Avaliar o impacto da graduação da doença degenerativa lombar (DDL) sobre o alinhamento sagital espinopélvico. Métodos Ao todo, 130 pacientes (dade média: 57 anos; 75% do sexo feminino) com dor lombar associada a DDL foram prospectivamente incluídos. A gravidade da DDL foi definida pelos seguintes achados nas radiografias anteroposterior e de perfil da coluna lombar: osteofitose; perda de altura do disco intervertebral; esclerose na placa vertebral terminal; número de segmentos afetados; deformidades; e instabilidade objetiva. Os pacientes foram graduados segundo a DDL da seguinte maneira: grau 0-ausência de sinais de DDL na coluna lombar; grau I - sinais de DDL em até dois segmentos; grau II - envolvimento em três ou mais segmentos; grau III - quando associada a escoliose, espondilolistese ou laterolistese. Parâmetros radiográficos espinopélvicos, como incidência pélvica (IP), lordose lombar (LL), discrepância entre a IP e a LL (IP-LL), versão pélvica (VP), e eixo vertical sagital (EVS) foram analisados de acordo com os graus de DDL. Resultados Houve diferença nos parâmetros radiográficos comparando-se os graus de DDL, com os pacientes de grau III apresentando maiores valores de EVS (p= 0,001) e VP (p= 0,0005), o que denota maior inclinação anterior do tronco e maior retroversão pélvica do que os pacientes de graus 0 e I. Pacientes de grau III também apresentaram maiores valores de IP-LL, o que denota perda da lordose relativa ao valor da IP, do que pacientes grau I (p= 0,04). Conclusão Pacientes com DDL mais grave demonstraram uma tendência a maior desalinhamento sagital espinopélvico comparados com pacientes com graus mais leves.

Objective To study the parameters related to the insertion path of cortical screws and to describe this technique. Methods Computed tomography (CT) scans of 30 patients, as well as the measurements from the L1 to the L5 vertebrae, were studied. A second observer evaluated ten randomly-selected exams. The parameters studied included the lateral angle (LA) and the screw diameter (SD) as axial variables, and the cranial angle (CA) and screw length (SL) as sagittal variables. Results We studied 15 male patients (mean age: 31.33 years) and 15 female patients (mean age: 32.01 years). The LA varied between 13.8° and 20.89°, with a tendency to increase in the proximal to distal direction. The CA varied from 17.5° to 24.9°, with a tendency to decrease in the caudal direction. The SD ranged from 2.3 mm to 7.2 mm, with a tendency to increase as we progressed from proximal to distal. The SL varied from 19 mm to 45 mm, with a tendency to decrease as we proceeded from proximal (L1) to distal (L5). No statistical difference was observed between the genders or in the interobserver agreement regarding the values studied when comparing the sides. Conclusion The path of insertion of the cortical screw shows a variation in different populations. Therefore, we recommend a preoperative imaging study to reduce the surgical risks related to the technique. Resumo Objetivo Estudar os parâmetros anatômicos do trajeto de inserção do parafuso cortical e descrever sua técnica. Métodos Analisaram-se exames de tomografia computadorizada de 30 pacientes, e as medidas nas vértebras de L1 a L5 bilateralmente. Um segundo observador avaliou dez exames aleatoriamente. Os parâmetros incluíram o ângulo lateral (AL) e o diâmetro do parafuso (DP) como variáveis axiais, e o ângulo cranial (AC) e o comprimento do parafuso (CP) como variáveis sagitais. Resultados No total, havia 15 pacientes do sexo masculino (média de idade de 31,33 anos) e 15 do sexo feminino (média de idade de 32,01 anos). O AL variou de 13,8° a 20,89°, com uma tendência de aumento no sentido de proximal a distal. O AC variou de 17,5° a 24,9°, com tendência de diminuição no sentido caudal. O DP variou de 2,3 mm a 7,2 mm, havendo uma tendência ao aumento conforme avançamos de proximal a distal. O CP variou de 19 mm a 45 mm, havendo uma tendência de diminuição conforme avançamos de proximal (L1) a distal (L5). Não houve diferença estatística entre os sexos, nem diferenças na confiabilidade interobservador, quanto aos valores estudados quando comparados os lados. Conclusão A trajetória do parafuso de trajeto cortical apresenta variações em diferentes populações. Assim, recomendamos o estudo pré-operatório de imagens para reduzir os riscos cirúrgicos relacionados à técnica.

Objective The approachability of the cervicothoracic region anteriorly based on age and gender, and the possibility of anatomic variances in different geographic populations have not been previously investigated. The aim of the present work was to perform a radiographic analysis of Brazilian patients to assess anterior approachability of the cervicothoracic junction based on age and gender. Methods Retrospective radiographic analysis of 300 computed tomography scans. Patients were separated based on age and gender. The radiographic parameters studied were: horizontal level above the sternum (HLS), vertebral body angle (VBA), intervertebral disc line (IDL), and intervertebral disc line angulation (IDLA). Results The most frequent HLS and IDL were T2 (34.3%) and C7-T1 (46%) respectively. Vertebral body angleand IDLA had average values of 18 ± 8.94 and 19 ± 7.9 degrees, respectively. Males had higher values in both IDLA (p= 0.003) and VBA (p= 0.02). Older groups had higher values in both IDLA (p= 0.01) and VBA (p= 0.001). No differences were observed in HLS between gender (p= 0.3) or age groups (p= 0.79). No differences were seen in IDL between gender groups (p= 0.3); however, the older group had a more caudal level than the younger groups (p= 0.12). ConclusionsCompared to other populations, our sample had a more cephalad IDL and HLS. Vertebral body angle and IDLA were higher in males and higher angles for VBA and IDLA were shown for older groups. Intervertebral disc line was more caudal with aging. Resumo Objetivo A capacidade de acesso anterior à região cervicotorácica com base na idade e gênero do paciente e a possibilidade de variações anatômicas em diferentes populações geográficas ainda não foram investigadas. O objetivo deste trabalho foi realizar uma análise radiográfica de pacientes brasileiros para avaliar a acessibilidade anterior da junção cervicotorácica conforme idade e gênero. Métodos Análise radiográfica retrospectiva de 300 tomografias computadorizadas. Os pacientes foram separados por idade e gênero. Os parâmetros radiográficos estudados foram: nível horizontal acima do esterno (HLS, na sigla em inglês), angulação do corpo vertebral (VBA, na sigla em inglês), linha do disco intervertebral (IDL, na sigla em inglês) e angulação da linha do disco intervertebral (IDLA, na sigla em inglês). Resultados Os HLS e IDL mais frequentes foram T2 (34,3%) e C7-T1 (46%), respectivamente. Os valores médios de VBA e IDLA foram de 18 ± 8,94 e 19 ± 7,9 graus, respectivamente. Os homens apresentaram valores maiores de IDLA (p= 0,003) e VBA (p= 0,02). Os grupos de maior idade apresentaram valores maiores de IDLA (p= 0,01) e VBA (p= 0,001). Não houve diferenças de HLS entre os gêneros masculino e feminino (p= 0,3) ou faixas etárias (p= 0,79). Não foram observadas diferenças na IDL entre os gêneros masculino e feminino (p= 0,3); entretanto, o grupo mais velho apresentou nível mais caudal do que os grupos mais jovens (p= 0,12). ConclusõesEm comparação a outras populações, nossa amostra apresentou IDL e HLS mais cefálicos. AVBA e a IDLA foram maiores no gênero masculino, enquanto VBA e IDLA foram maiores em grupos mais velhos. A IDL era mais caudal em pacientes idosos.

Breast cancer (BC) is the most common malignant neoplasm in women worldwide. Chemotherapy (CT) remains essential in the treatment of this type of tumour. Patients may present musculoskeletal disorders due to the side effects of CT, which can lead to inability to walk, fall, or fractures associated with balance disorders. The objective of the present review is to analyse postural alterations in patients with BC undergoing CT. Previous reports both prospective and retrospective cohort studies from 2010 to 2020, were included. The results show a strong relationship between postural alterations and patients with BC undergoing CT treatment. These data suggest that exposure to CT is an important factor not only for the presence of balance alterations and risk of falls but also for the decrease of quality of life in these patients. These results point out the need to diagnose and assess postural alterations to prevent functional impact in BC patients through exercise programs.

The non-linear response of dielectrics to intense, ultrashort electric fields has been a sustained topic of interest for decades with one of its most important applications being femtosecond laser micro/nano-machining. More recently, renewed interests in strong field physics of solids were raised with the advent of mid-infrared femtosecond laser pulses, such as high-order harmonic generation, optical-field-induced currents, etc. All these processes are underpinned by photoionization (PI), namely the electron transfer from the valence to the conduction bands, on a time scale too short for phononic motion to be of relevance. Here, in hexagonal boron nitride, we reveal that the bandgap can be finely manipulated by femtosecond laser pulses as a function of field polarization direction with respect to the lattice, in addition to the field's intensity. It is the modification of bandgap that enables the ultrafast PI processes to take place in dielectrics. We further demonstrate the validity of the Keldysh theory in describing PI in dielectrics in the few TW/cm2 regime., 13 pages, 4 figures