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Asymmetries and poor Y balance test (YBT) performance are associated with an increased risk of injuries in athletes. The aim of this study was to investigate the association between YBT performance with biomechanical variables in runners. The runners underwent the YBT, followed by the assessment of center of pressure, plank position, muscle strength (MS) of hip flexors, extensors, abductors, and external rotators, knee extensors, ankle dorsiflexion range of motion (ROM), Q angle, forefoot alignment, and passive hip internal rotation. Associations between variables were examined using multiple linear regression models with the Bayesian Information Criterion. 122 cases were analyzed. The R2 values were 0.38; 0.05; 0.06; and 0.15 for the anterior, posteromedial, posterolateral and composite directions models, respectively. The anterior reach in the YBT was associated with ankle dorsiflexion ROM [Sβ 95%IC: 0.43 (0.32–0.55)], passive hip internal rotation [Sβ 95%IC: 0.35 (0.24–0.47)], MS of the hip extensors [Sβ 95%IC: 0.19 (0.07–0.31)] and forefoot alignment [Sβ 95%IC: 0.14 (-0.25-0.02)]. The posteromedial and posterolateral reach were associated with MS of the hip flexors [Sβ 95%IC: 0.23 (0.09–0.37) and 0.24 (0.11–0.38)], respectively. The composite score was associated with MS of the hip flexors [Sβ 95%IC: 0.31 (0.18–0.45)], ankle dorsiflexion ROM [Sβ 95%IC: 0.24 (0.10–0.37)] and Q angle [Sβ 95%IC: 0.18 (0.04–0.31)]. YBT performance in different directions demonstrated specific associations with key biomechanical factors. [ABSTRACT FROM AUTHOR]

In small-scale, low-density or high-speed flows, the mean free path of the gas and its molecular interaction with a solid interface are key properties for the analysis of heat transfer mechanisms occurring in many flow processes ranging from micro-scale to aerospace applications. Here, we specifically examine the effects of temperature jump at the gas–solid interface on the convection from a cylinder in the high-speed slip flow regime. By employing the classical Smoluchowski temperature jump condition, we derive a simple model that explicitly predicts the heat flux (Nusselt number, Nu) from the surface of a small heated cylinder simulating a hot-wire as a function of the Knudsen number (Kn) and the thermal (or energy) accommodation coefficient (σ T) of the gas molecules interacting with the surface. The model, derived analytically and verified empirically by numerical simulations, helps clarifying coupled gas rarefaction and temperature effects on the heat transfer from a cylinder in high-speed flow. In addition, we employ the model reversely to propose a novel methodology to compute gas–surface thermal accommodation or temperature jump coefficients from hot-wire measurements. • A model of heat transfer from a cylinder in high-speed flow taking into account temperature jump in the slip flow regime. • Experiments and direct numerical simulations demonstrate the impact of slip flow effects on the heat transfer from a hot-wire sensor. • A novel methodology to determine temperature jump coefficients from hot-wire measurements. [ABSTRACT FROM AUTHOR]

to provide evidence for the effects of whole-body electromyostimulation (WB-EMS) on health-related outcomes compared to the effects of minimal or non-intervention for older people in the short/medium/long term. seven databases (MEDLINE, Embase, CENTRAL, CINAHL, Scopus, SPORTDiscuss and Web of Science) were electronically searched in April 2020 and updated in March 2021. included studies were randomized controlled trials (RCTs) involving WB-EMS that assessed effects on health-related outcomes, risks and adverse events in older people (>60 years). the following data were obtained: author and publication year, follow-up, detailed information of older characteristics, current parameters/intensity and outcomes. a random effects model was used with effect size reported as SMD. Statistical heterogeneity was assessed using the I2 test. 13 RCTs met the eligibility criteria. Meta-analysis found: large effects of WB-EMS on reducing sarcopenia Z-score (ES: 1.44[-2.02: 0.87] p= <.01) and improving isometric strength leg extensors (ES: 0.81[0.41: 1.21] p= <.01) at medium and long-term, respectively. Moderate effects of WB-EMS on improving handgrip strength (ES: 0.58[0.23: 0.92] p= <.01) and habitual gait speed (ES: 0.69[0.31: 1.07] p= <.01) at medium-term and improving appendicular skeletal muscle mass (ES:0.69 [0.30: 1.09] p= <.01) at long-term. Non-significant effect of WB-EMS on waist circumference (p =.17) and triglycerides (p =.20) at medium-term. Non-significant effects of WB-EMS on improving creatine kinase concentrations, C-reactive protein, and interleukin 6 at medium-term. This review provides further evidence for significant, moderate to large effect sizes of WB-EMS on sarcopenia, muscle mass and strength parameters, but not on waist circumference and triglycerides. PROSPERO database no. CRD42019134100. Clinical relevance: - The WB-EMS presented as an alternative intervention to increase the muscle mass, strength parameters, functional capacity in older people. - No effect of WB-EMS was observed on waist circumference and triglycerides in older people in the medium and long-term follow-up. - Faster effects of WB-EMS for handgrip strength and usual gait speed of older people (at medium-term) were seen with the addition of protein supplementation. - There were no adverse events related to the WB-EMS, suggesting that the WB-EMS is safe for use in the older people. [ABSTRACT FROM AUTHOR]

Carotid free-floating thrombus (CFT) is a rare cause of stroke describing an intraluminal thrombus that is loosely associated with the arterial wall and manifesting as a filling defect fully surrounded by flow on vascular imaging. Unfortunately, there is no clear consensus among experts on the ideal treatment for this pathology. Retrospective analysis of acute ischemic stroke (AIS) and transient ischemic attack (TIA) patients diagnosed with CFT on computed tomography angiogram (CTA) between January 2015-March 2023. We aimed to compare two treatment regimens: anticoagulation (ACT) and antiplatelet (APT) in the treatment of CFT. APT regimens included the use of dual or single antiplatelets (DAPT or SAPT; aspirin, clopidogrel and ticagrelor) and ACT regimens included the use of direct oral anticoagulants, warfarin, heparin or low molecular weight heparin +/- ASA. Patients that underwent mechanical thrombectomy were excluded. During study time there were 8252 acute ischemic stroke hospitalizations, of which 135 (1.63 %) patients were diagnosed with CFT. Sixty-six patients were included in our analysis. Patients assigned to APT were older (60.41years ± 12.82; p < 0.01). Other demographic variables were similar between ACT and APT groups. Complete CFT resolution on repeat vascular imaging was numerically higher at 30 days (58.8 vs 31.6 %, respectively; p = 0.1) and at latest follow-up (70.8 vs 50 %; p = 0.1) on ACT vs APT, respectively without reaching statistical significance. Similarly, there was numerically higher rates of any ICH with ACT compared to APT but it did not achieve statistical significance (27.6 % vs 13.5 %; p = 0.5). There were similar rates of PH1/2 hemorrhagic transformation, independence at discharge and similar hospital length of stay between ACT and APT groups. Patients assigned to APT were more likely to be discharged on their assigned treatment compared to those assigned to ACT (86.5 vs 55.2 %; p < 0.001). The rate of 30-day recurrent stroke was comparable among ACT and APT at 30 days (3.4 vs 0 %; p = 0.1, respectively). Subgroup analysis comparing exclusive ACT vs Dual APT lead to similar results. Our study showed comparable efficacy and safety outcomes in CFT patients who were exclusively managed medically with ACT vs APT. Larger prospective studies are needed. [ABSTRACT FROM AUTHOR]

• Blood-brain barrier models still lack capacity to combine simplicity and performance. • Neural models are diverse resource-wise but still limited in characterization. • Intercellular interplay is still the main focus of neurovascular models. • Consolidated individual models must be combined to form novel neurovascular models. Clinical trials continue to fall short regarding drugs to effectively treat brain-affecting diseases. Although there are many causes of these shortcomings, the most relevant are the inability of most therapeutic agents to cross the blood–brain barrier (BBB) and the failure to translate effects from animal models to patients. In this review, we analyze the most recent developments in BBB, neural, and neurovascular models, analyzing their impact on the drug development process by considering their quantitative and phenotypical characterization. We offer a perspective of the state-of-the-art of the models that could revolutionize the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

• A new human pose regression method from RGB images. • The proposed soft-argmax operation. • Contextual aggregation for refining predictions. • State-of-the-art results on important 2D pose estimation benchmarks among regression methods. In this paper, we tackle the problem of human pose estimation from still images, which is a very active topic, specially due to its several applications, from image annotation to human-machine interface. We use the soft-argmax function to convert feature maps directly to body joint coordinates, resulting in a fully differentiable framework. Our method is able to learn heat maps representations indirectly, without additional steps of artificial ground truth generation. Consequently, contextual information can be included to the pose predictions in a seamless way. We evaluated our method on two challenging datasets, the Leeds Sports Poses (LSP) and the MPII Human Pose datasets, reaching the best performance among all the existing regression methods. Source code available at: https://github.com/dluvizon/pose-regression. [ABSTRACT FROM AUTHOR]

Given many emerging indications for endovascular interventions in ischemic strokes, a safe and effective adjuvant antiplatelet regimen for acute revascularization has become a subject of interest. Ticagrelor is a direct oral P2Y12 inhibitor that may achieve rapid platelet suppression than standard oral therapies. We report our experience of Ticagrelor use in revascularization of acute large arterial steno-occlusive disease, describing procedural post-procedure thrombotic events, major hemorrhages, and other clinical outcomes. This was a single-center retrospective case series of large steno-occlusive disease requiring endovascular reperfusion with emergent adjuvant Ticagrelor, defined as 30 min of the procedure from skin puncture to closure of the arteriotomy. Major outcomes investigated were thromboembolism in the target artery, and symptomatic intracranial or extracranial major hemorrhages. Additional analyses were performed with respect to timing of the administration and use of rescue GPIIb/IIIa inhibitors if any. 73 consecutive patients were identified, presenting with severe ischemic stroke (median NIHSS 16) of large artery origin. 67% required stent placement (45% cervical carotid, 22% intracranial artery), 9.5% angioplasty and 23% mechanical thrombectomy only. Two experienced symptomatic in-stent occlusion, and 7 experienced major hemorrhages (9.5%) including 3 fatal symptomatic intracranial hemorrhages (4.1%). Among 19 subjects (26%) who received pretreatment with Ticagrelor, there were fewer GPIIb/IIIa administration, angioplasty and stenting, without yielding benefit in functional outcome or mortality. GPIIb/IIIa was administered as rescue therapy in 45 subjects (62%), which was found associated with increased bleeding compared to patients receiving Ticagrelor only, in whom no bleeding complications were recorded (16% vs. 0%; p = 0.03). We report our findings on Ticagrelor as an adjuvant antiplatelet therapy in ischemic stroke of large arterial origin requiring emergent revascularization. Effectiveness, safety, need for additional rescue treatment, and comparison to other commonly used oral antiplatelets should be investigated in future prospective studies. [ABSTRACT FROM AUTHOR]

Meshless methods are a type of numerical method used to simulate continuum mechanics problems. These methods have been applied to several types of problems, there are a few works using meshless method focused on dynamic problems, but most works study static loading conditions. The current work aims at using two different meshless methods, the Radial Point Interpolation Method (RPIM) and the Natural Neighbours RPIM (NNRPIM), in a dynamic problem, specifically forced vibrations. This problem requires time integration, therefore three different time integration methods have also been tested, namely: the Central Difference Method (CDM), the Wilson method, and the Newmark method. The CDM is an explicit method, while the other two are implicit. A discretization study was performed to assess the ideal nodal discretization before the numerical and time integration methods are validated. For the implicit methods, different time step lengths were also tested. In the final example damping was introduced. The results prove the validity of the two meshless methods by having similar results to the Finite Element Method (FEM) using the three distinct time integration methods, different loading conditions, and damping. [ABSTRACT FROM AUTHOR]

Objective Endovascular thrombectomy has become the gold standard for acute ischemic stroke intervention in appropriate patients. Occasionally, thrombectomy through the standard craniocervical artery related to the affected territory is not technically feasible due to patient-specific anatomic issues. Methods This is a retrospective review of cases where intracranial access was achieved via an unaffected circulation across the Circle of Willis. Results A technically successful thrombectomy is described in detail in 3 cases along with technical challenges encountered. Conclusions Thrombectomy across the Circle of Willis is a potential bailout technique for select, complex cases. Further investigation is warranted. [ABSTRACT FROM AUTHOR]

Aiming at investigating the effect of the polymer molecular weight ( M w ) on the physical and gas permeation properties of poly(ionic liquid)-ionic liquid (PIL–IL) composites, this work focuses on membranes based on variable M w pyrrolidinium-PILs having [C(CN) 3 ] – as counter-anion and different amounts (20, 40 and 60 wt%) of free [C 2 mim][C(CN) 3 ] IL. Although all the prepared composite materials have high thermal stability ( T onset > 556 K) for post-combustion CO 2 separation, the evaluation of the film forming ability shows that it is not possible to obtain free standing PIL–IL membranes using the Low M w PIL (average < 100 kDa). The formed Medium M w (average 200 – 350 kDa) and High M w (average 400 – 500 kDa) PIL–IL membranes present similar mechanical properties in terms of Young´s modulus, tensile strength and elongation at break. The gas permeabilities and diffusivities are dependent on the M w of the PIL used. The Medium M w PIL–IL membranes display higher CO 2 permeabilities (14.6 – 542 Barrer) than those (8.0–439 Barrer) observed for High M w PIL–IL composites. Despite the M w of the PIL used, the incorporation of high free IL contents increases both CO 2 permeability and CO 2 /N 2 permselectivity. Consequently, the finest CO 2 /N 2 separation performances, overcoming the 2008 upper bound in the Robeson plot, were obtained for the High and Medium M w PIL–60 IL composites, respectively, with CO 2 permeabilities of 439 and 542 Barrer and CO 2 /N 2 permselectivities of 64.4 and 54.0. [ABSTRACT FROM AUTHOR]

Background: Musculoskeletal disorders are prevalent and represent the most common health problem among the working population in industrially-developing countries, with considerable costs and impact on quality of life. Despite the high incidence of disability insurance claims among Brazilian manufacturing-sector workers, only a few studies assessed musculoskeletal disorders prevalence. Objective: To provide information on the prevalence of musculoskeletal disorders among manufacturing-sector workers and to explore the relationship between musculoskeletal disorders and sociodemographic and occupational characteristics in a medium metallurgical company located in Brazil. Methods: A cross-sectional study was carried out. Data was collected through the use of a specifically-designed questionnaire and the items used to collect musculoskeletal disorders data were based on the Nordic Musculoskeletal Questionnaire. Descriptive statistics were used and multivariate logistic regression analysis (p<0.02) was performed to explore the associations between musculoskeletal disorders and potential risk factors. Results: The upper limb was the most frequently affected body region among manufacturing-sector workers: shoulder (24.8%), elbow and/or forearm (15.5%), wrist and/or hand (19.0%). Adjusted logistic regression analysis showed that company experience (p=0.02), presence of sleep disorders (p=0.00), self-reported general health state (p=0.00) and perform work pause (p=0.00) were significant risk factors for development of musculoskeletal disorders. Conclusion: Sociodemographic and work-related aspects are influential risk factors for musculoskeletal disorders. These results add comprehension about musculoskeletal disorders prevalence and suggest a need for greater emphasis on prevention strategies. [ABSTRACT FROM AUTHOR]

We study the Constrained-degree percolation model on the square lattice. Through an analysis of this model on finite square lattices of length n we found numerical evidence that the distribution function of the density of open bonds converges, when n → ∞ , to the normal distribution around the average density. • The Constrained-degree percolation model on the square lattice is studied. • The density of open bonds satisfies the central limit theorem. • Precise estimates for the density of open bonds are obtained. [ABSTRACT FROM AUTHOR]

Background Context: The study of low back pain (LBP) is complex, and the physical and psychological aspects, including kinesiophobia, should be considered. Several studies have investigated the relationship between kinesiophobia and functionality in patients with chronic LBP. However, to the best of the authors' knowledge, no studies have investigated the association between kinesiophobia and self-reported assessments of disability and physical performance in elderly patients with acute LBP.Purpose: The study aimed to investigate the association between kinesiophobia and self-reported and physical performance measures among the elderly with acute LBP.Design: This was an observational, cross-sectional, ancillary study of the Back Complaints in the Elders study, a longitudinal observational epidemiologic research project by an international consortium involving Brazil, the Netherlands, and Australia.Patient Sample: Sample selection was carried out by convenience. The study included women from the community aged 60 years old and older who presented with a new episode of LBP. Volunteers with severe diseases, as well as visual, hearing, and mobility losses, or cognitive dysfunction, were excluded. Four hundred fifty nine elderly women (mean age: 69.0±6.1 years) were included.Outcome Measures: Kinesiophobia was evaluated by Fear Avoidance Beliefs Questionnaire (FABQ), subscale FABQ-Phys. Functionality was investigated by the Roland-Morris Questionnaire and the gait speed test.Methods: Statistical analysis was performed using hierarchical linear regression model. Statistical significance was established at the level of .05.Results: The additional predictive value because of the inclusion of the FABQ-Phys was 0.1%, using the Roland-Morris score, and 0.2% for the gait speed test.Conclusions: This was the first study to investigate the association between the FABQ-Phys and functionality in elderly patients with acute LBP. The results provide preliminary evidence that kinesiophobia assessed by the FABQ-Phys cannot be generalized to disability. [ABSTRACT FROM AUTHOR]

Brain–computer interface (BCI) systems based on electroencephalography have been increasingly used in different contexts, engendering applications from entertainment to rehabilitation in a non-invasive framework. In this study, we perform a comparative analysis of different signal processing techniques for each BCI system stage concerning steady state visually evoked potentials (SSVEP), which includes: (1) feature extraction performed by different spectral methods (bank of filters, Welch's method and the magnitude of the short-time Fourier transform); (2) feature selection by means of an incremental wrapper, a filter using Pearson's method and a cluster measure based on the Davies–Bouldin index, in addition to a scenario with no selection strategy; (3) classification schemes using linear discriminant analysis (LDA), support vector machines (SVM) and extreme learning machines (ELM). The combination of such methodologies leads to a representative and helpful comparative overview of robustness and efficiency of classical strategies, in addition to the characterization of a relatively new classification approach (defined by ELM) applied to the BCI-SSVEP systems. [ABSTRACT FROM AUTHOR]

Background: Carotid web (CaW) is non-atheromatous, shelf-like intraluminal projection, generally affecting the posterolateral wall of the proximal internal carotid artery, and associated with embolic stroke, particularly in younger patients without traditional stroke risk factors. Treatment options for symptomatic CaWs include interventional therapy with carotid endarterectomy or carotid stenting versus medical therapy with antiplatelet or anticoagulants. As safety and efficacy of these approaches have been incompletely delineated in small-to-moderate case series, we performed a systematic review of outcomes with interventional and medical management.Methods: Systematic literature search was conducted and data analyzed per PRISMA guidelines (Preferred Reporting Items for Systemic Reviews and Meta-Analyses) from January 2000 to October 2021 using the search strategy: "Carotid web" OR "Carotid shelf" OR "Web vessels" OR "Intraluminal web". Patient-level demographics, stroke risk factors, technical procedure details, medical and interventional management strategies were abstracted across 15 series. All data were analyzed using descriptive statistics.Results: Among a total of symptomatic 282 CaW patients across 14 series, age was 49.5 (44-55.7) years, 61.7% were women, and 76.6% were black. Traditional stroke risk factors were less frequent than the other stroke causes, including hypertension in 28.6%, hyperlipidemia 14.6%, DM 7.0%, and smoking 19.8%. Thrombus adherent to CaW was detected on initial imaging in 16.2%. Among 289 symptomatic CaWs across 15 series, interventional management was pursued in 151 (52.2%), carotid artery stenting in 87, and carotid endarterectomy in 64; medical management was pursued in 138 (47.8%), including antiplatelet therapy in 80.4% and anticoagulants in 11.6%. Interventional and medical patients were similar in baseline characteristics. The reported time from index stroke to carotid revascularization was median 14 days (IQR 9.5-44). In the interventional group, no periprocedural mortality was noted, major periprocedural complications occurred in 1/151 (0.5%), and no recurrent ischemic events were observed over follow-up range of 3-60 months. In the medical group, over a follow-up of 2-55 months, the recurrence cerebral ischemia rate was 26.8%.Conclusion: Cumulative evidence from multiple series suggests that carotid revascularization is a safe and effective option for preventing recurrent ischemic events in patients with symptomatic carotid webs. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To investigate the effect of 2 standardized exercise programs, muscle strength exercises (SE) and aerobic exercises (AE), on the plasma levels of brain-derived neurotrophic factor (BDNF) and depressive symptoms in 451 elderly women. Design: A randomized controlled trial. Setting: Belo Horizonte/MG–Brazil. Participants: Community-dwelling older women (N=451; age, 65–89y). Intervention: The participants were divided into 2 groups: SE and AE. Both protocols lasted 10 weeks, and 30 sessions (1-h sessions) in total were performed 3 times a week under the direct supervision of physical therapists. Main Outcome Measures: Plasma levels of BDNF (enzyme-linked immunosorbent assay) and depressive symptoms (Geriatric Depression Scale). Results: There was a significant difference for BDNF plasma levels between the SE and AE groups (P=.009). Post hoc analysis revealed a pre-post intervention difference in BDNF levels only for the SE group (P=.008). A statistically significant difference was found for the pre- and postintervention Geriatric Depression Scale scores in both groups (P=.001), showing that the effects of both exercise protocols were comparable regarding depressive symptoms (P=.185). Conclusions: The present findings have demonstrated the positive effect of muscle strengthening and aerobic intervention on depressive symptoms in community-dwelling elderly women. Interestingly, only SE significantly increased the plasma levels of BDNF in our sample. The positive effects of physical exercise on depressive symptoms in the elderly were not mediated by BDNF. [ABSTRACT FROM AUTHOR]

The influence of statin therapy on cerebral vasomotor function has not been fully characterized. We report the effects of high-dose atorvastatin therapy on cerebral vasomotor reactivity (VMR) in patients with controlled hypertension and dyslipidemia. We prospectively enrolled 36 patients with controlled hypertension and a low-density lipoprotein (LDL) cholesterol concentration >100 mg/dL. Atorvastatin 80 mg was given daily for 6 months and then discontinued. VMR was assessed by hypercapnic and hypocapnic transcranial Doppler challenge in both the right and left middle cerebral artery (MCA) at baseline, and after 3 and 6 months of therapy. Forty-five days after statin cessation, a repeat VMR was performed. VMR impairment was defined as ≤70%. Blood pressure, lipid levels, liver function, and creatine kinase level were monitored. Mean patient age was 60 years, 16 were men, and 13 had a previous history of subcortical infarction. Mean LDL cholesterol level before treatment was 154 ± 30 mg/dL. Atorvastatin lowered LDL by 53% at 3 months and by 46% at 6 months. Baseline VMR was 71% ± 21% in the right MCA and 70% ± 19% in the left MCA. No significant effect of atorvastatin on VMR was seen at 3 months and 6 months in the study population as a whole. In the subgroup of patients with baseline VMR impairment, atorvastatin therapy was associated with significantly improved VMR at both 3 and 6 months. This effect persisted for at least 45 days after discontinuation of therapy. Our findings indicate that high-dose atorvastatin therapy can significantly improve impaired cerebral VMR, and that the effects of atorvastatin on VMR persist for 1.5 months after discontinuation of therapy. We found no benefit of atorvastatin therapy in patients with preserved baseline vasoreactivity. [ABSTRACT FROM AUTHOR]

Abstract: Among a series of parameters, power quality studies are concerned with voltage unbalances, which represent the voltage magnitude and phase deviation from nominal values. In order to determine the influence of the network''s parameters on voltage unbalances, and to provide exact solutions to reduce or even eliminate them, the present study develops and presents two methods. First, a sensitivity analysis is used to determine the influence of each parameter, and then analytical solutions are developed in order to provide the changes needed for correction. The quantification index considered is the symmetrical components method. [Copyright &y& Elsevier]

Background and Purpose: The baseline characteristics of patients with symptomatic carotid web (CaW) are unclear. We investigate demographic and cerebrovascular risk factors in patients with this overlooked stroke etiology.Methods: We identified consecutive patients diagnosed with symptomatic CaW at a comprehensive stroke center from July 2014-December 2018. These patients were matched at a 1:4 ratio (based on age and NIHSS scores) to create a control group of acute ischemic stroke (AIS) patients with non-CaW etiologies from the local GetWithTheGuidelines stroke database.Results: Thirty patients with symptomatic CaW were compared to 120 AIS patients with non-CaW etiologies. Symptomatic CaW patients were more likely to be female (73.3 vs. 44.2%; p = 0.004) and black (86.7 vs. 64.2%; p = 0.02). Symptomatic CaWs patients had a fewer absolute number of modifiable cerebrovascular risk factors (1.7±1.1 vs. 2.5±1.2; p = 0.002), lower rates of hypertension (43.4 vs. 63.3%; p = 0.04), and a more favorable lipid profile with lower average LDL (89.5±30.3 vs. 111.2±43.7 mg/dL; p = 0.01) and higher average HDL (47.9±11.3 vs. 42.2±13.8 mg/dL; p = 0.01) as compared to strokes with non-CaW etiology. Symptomatic CaW patients were more likely to have a large vessel occlusion (80.0 vs. 51.7%; p = 0.005), despite similar e-ASPECTS between the groups (8.1±2.1 vs. 8.3±2.2; p = 0.30). On multivariable analysis, symptomatic CaW was an independent predictor of independence at discharge (OR 3.72; 95%CI 1.27-10.94).Conclusion: A gender and racial predilection of symptomatic CaWs may exist as females and blacks were were found to be more likely affected. Symptomatic CaW patients have a more benign cerebrovascular risk factor profile corroborating the proposed mechanism of local stasis and thromboembolism. Despite presenting more commonly with LVO, symptomatic CaW was associated with good functional outcome, warranting further studies. [ABSTRACT FROM AUTHOR]

• The effects of specific gravity and mean shear on three-dimensional sphere dynamics were investigated experimentally. • Sphere trajectories, velocities and rotational orientations are reconstructed. • The importance of lift, forward drag and wall friction are discussed. • Less dense spheres lifted off of the wall and translated with only weak rotations. • Denser spheres first slid then partially rolled forward along the wall while experiencing small repeated lift-off events. Individual magnetic wax spheres with specific gravities of 1.006, 1.054 and 1.152 were released from rest on a smooth wall in water at friction Reynolds numbers, R e τ = 680 and 1320 (sphere diameters d + = 58 and 122 viscous units, respectively). Three-dimensional tracking was conducted to understand the effects of turbulence and wall friction on sphere motions. Spheres subjected to sufficient mean shear initially lifted off of the wall before descending back towards it. These lifting spheres translated with the fluid above the wall, undergoing saltation or resuspension, with minimal rotations about any axis. By contrast, spheres that did not lift off upon release mainly slid along the wall. These denser spheres lagged the fluid more significantly due to greater wall friction. As they slid downstream, they began to roll forward after which small repeated lift-off events occurred. These spheres also rotated about both the streamwise and wall-normal axes. In all cases, the sphere trajectories were limited to the buffer and logarithmic regions, and all wall collisions were completely inelastic. In the plane parallel to the wall, the spheres migrated in the spanwise direction about 12% of the streamwise distance traveled suggesting that spanwise forces are important. Variations in sphere kinematics in individual runs were likely induced by high and low momentum zones in the boundary layer, vortex shedding in the sphere wakes, and wall friction. The repeated lift-offs of the forward rolling denser spheres were attributed to a Magnus lift. [ABSTRACT FROM AUTHOR]

Introduction: Carotid web is a radiographic entity located in the posterior aspect of the origin of the internal carotid arteries, considered to be a pathologic equivalent to intimal fibromuscular dysplasia, and has been implicated in acute ischemic strokes. The mechanism underlying its development is unknown and it remains unclear if this lesion is congenital or acquired. The aim of our study was to determine the frequency of carotid webs in a pediatric population with acute ischemic stroke (AIS).Methods: A retrospective review of neck CTA, MRA, or DSA images in a pediatric population with acute ischemic stroke was performed to determine the occurrence of carotid webs. Two fellowship-trained neurointerventionists performed independent vascular imaging review.Results: We identified forty-seven cases of childhood acute ischemic stroke (55% male; median age, 9 years). Congenital heart disease, sickle cell disease, infection, and recent head/neck trauma were the most common risk factors. Eight of the ischemic stroke cases were located in multiple vascular territories. Neck arterial imaging was undertaken in twenty-four patients. No carotid webs were detected in the studied pediatric stroke population. (The correlation coefficient for the determination of webs was Kappa = 1.00; p < 0.001).Conclusion: This study failed to find evidence that carotid webs are congenital. More studies are needed for a better understanding of carotid web origin, natural evolution, and the potential implications for treatment. [ABSTRACT FROM AUTHOR]

Background: Young individuals with symptomatic carotid webs may be predisposed to ischemic strokes. However, evidence remains scarce. This investigation reports the frequency of carotid webs among patients with cryptogenic strokes compared to a control group.Methods: Consecutive cryptogenic ischemic strokes and trauma patients were identified. Additional inclusion criteria required age 18-60 years and availability of head/neck computed tomography (CT) angiography. CT angiogram (CTA) neck images were evaluated independently by 2 fellowshiptrained specialists. A carotid web was defined by a shelf-like, linear filling defect in the posterior internal carotid artery bulb.Results: Of 1877 patients presenting with ischemic strokes in 2015-2017, 165 were diagnosed with cryptogenic strokes, 51 of whom met the inclusion criteria of age and CTA availability. Fifty one trauma cases were matched for age and sex. After imaging analysis, 13 carotid webs (25%) were identified in the 51 cryptogenic stroke group versus 0 (0%; P < .001) in trauma subjects. Thirty-nine of the 51 cryptogenic ischemic stroke patients were found with carotid anterior distribution infarcts, of which 9 (23%) were found with ipsilateral carotid webs. There were more proximal large vessel occlusions in the cryptogenic patients with carotid webs, compared to those without (P = .04). All carotid webs led to less than 30% degree of stenosis.Conclusions: Carotid webs were found at a significantly higher frequency in patients with cryptogenic ischemic strokes compared to controls, indicating a potentially thrombogenic nature of these lesions in young patients. Additionally, intracranial large vessel occlusions were more common in patients with symptomatic carotid webs, presenting with ipsilateral strokes. [ABSTRACT FROM AUTHOR]

The use of adhesive joints has significantly increased in recent years, mainly due to being lighter than other joining alternatives. Although its importance, currently, the amount of works devoted to the free vibration response of adhesive joints is not very extensive. So, this work performs a free vibration parametric study of a Single Lap Joint (SLJ) using the Radial Point Interpolation Method (RPIM). Since this numerical method has never been used to solve this type of problem, RPIM results were compared and validated with FEM solution of a Step-Lap Joint (S-LJ), documented in a previous work. The comparison shows the similarity between the numerical approaches. After validating the RPIM, the parametric study was performed. It was found that geometrical and material changes to the adhesive are significantly less relevant than changes to the adherents. Changes to the overlap length differently influenced distinct vibration modes, some modes did not change at all, while others increased as the overlap length augments. [ABSTRACT FROM AUTHOR]

Adhesive joints are being increasingly used in various industries, including the automotive or the wind turbines industries. Such increasing interest is a direct result of its high structural efficiency and also the product of its related scientific research. Therefore, the state-of-the-art on adhesive joints is significantly expanding. The current work aims to discuss the most recent works dedicated to the numerical analysis of the dynamic behaviour of adhesive joints. Dynamic behaviour was divided into three separate fields: fatigue, variable strain rate and impact, and modal analysis. It was found that Cohesive Zone Models are a popular approach to study fatigue, variable strain rates and impact. Additionally, the available literature focused on fatigue and impact is more extensive than the one focused on modal analysis. Overall, it was found that the available research on the numerical analysis of the dynamic behaviour of adhesive joints is increasing at a solid rate, and many geometrical and material variations have been tested numerically. With this review designers and researchers of adhesive joints should be able to choose the most suitable numerical technique for their specific dynamic analysis. [ABSTRACT FROM AUTHOR]

Abstract: The relations between the kernels, as well as the cokernels, of Toeplitz operators are studied in connection with certain relations between their symbols. These results are used to obtain some Fredholm type properties for operators with symbols, whose determinant admits a bounded Wiener–Hopf factorization. [Copyright &y& Elsevier]

Panstrongylus megistus , a potential vector of Chagas disease, currently occupies a wider geographic distribution in Brazil than Triatoma infestans , another member of the hemipteran Reduviidae family and a vector of the same disease. A small heterochromatic body (chromocenter) formed by the Y chromosome is evident in the somatic cells of P. megistus , differing in size and chromosome type contribution from the well-studied chromocenters present in T. infestans . While the overall distribution of histone epigenetic marks differ when comparing the heterochromatin and euchromatin territories in T. infestans , no similar data have been established for other hemipteran reduviids, including P. megistus . In the present work, histone acetylation and methylation marks were investigated in cells of Malpighian tubules of P. megistus 5th instar nymphs using immunocytochemical assays and compared to previously published data for T. infestans . Although similarities between these species were found regarding absence of acetylated H3K9, H4K8 and H4K16, and H3K9me and H3K9me 2 in the chromocenter, presence of these marks in euchromatin, and presence of H3K9me 3 in the chromocenter, no intimate association of acetylated H4K8 and 18S rDNA was revealed in the chromocenter of P. megistus . The elevated abundance of H3K9me 2 marks at the nuclear periphery in P. megistus cells, differing from data for T. infestans , is suggested to reflect differences in the interaction of lamina-associated chromatin domains with the nuclear lamina, methyl-transferase modulation and/or association with the last DNA endoreplication step in 5th instar nymphs, which is a matter for further investigation. [ABSTRACT FROM AUTHOR]

Analyzing temporal changes in forest amount and configuration is paramount to better design future forest management interventions. Such analyses are especially required for tropical biomes, which are usually subject to dynamic and heterogeneous land uses. Recent studies have suggested that many tropical biomes are passing through the process of “forest transition”, i.e. an overall change from forest loss to forest gain. However, this hypothesis remains scarcely tested, due to the difficulty of obtaining detailed, quantitative historical records of forest cover. In this study, we investigate 38 years of land use change in Brazil's Atlantic Forest, a biodiversity hotspot, from 1976 to 2014, using multitemporal datasets from aerial photographs and satellite images. We classified the historical series to produce land use maps and calculated a set of landscape metrics, including total forest cover, patch size, patch shape and patch connectivity. Our results indicated non-linear changes through time in forest loss and gain and also in landscape structure, which can be classified into two distinct periods. The first period (1976–1996) was marked by expressive forest loss and fragmentation, whereas the second (1996–2014) was characterized by a much less intense forest dynamics, with little deforestation being balanced by forest regeneration. We attribute the forest dynamics observed to temporal changes in socioeconomic factors, such as increasing human settlements and changes in environmental protection policies. Our results show that current forests are a heterogeneous mosaic of forests with different ages, and support the hypothesis that forest transition is occurring in Atlantic Forest landscapes. [ABSTRACT FROM AUTHOR]

Balloon guide catheters (BGCs) can be used during cervical carotid stenting as a proximal protection strategy to minimize thromboembolic procedural complications (Video 1). A 9-French BGC can be swiftly inflated before each embologenic step of carotid stenting (microwire crossing, prestent angioplasty, stenting, poststent angioplasty); aspirated; and deflated. We present 2 unique cases in which the impact of BGC aspiration is demonstrated on cervical carotid stenting for atherosclerotic stenoocclusive disease. On deflation of the poststent angioplasty balloon with concomitant aspiration of the BGC through a 60-mL vacuum syringe, stent collapse was noted. Stent self-reexpansion was documented after reversal of negative pressure from the vacuum syringe, allowing for gentler aspiration. Awareness and early recognition of this potential for vessel wall collapse with aspiration are important to prevent vessel/stent collapse, inefficient aspiration, and resultant embolization of debris. Gradual aspiration is favored. [ABSTRACT FROM AUTHOR]