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1.
Orthod Craniofac Res ; 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321788

RESUMEN

OBJECTIVE: To investigate the accuracy of artificial intelligence-assisted growth prediction using a convolutional neural network (CNN) algorithm and longitudinal lateral cephalograms (Lat-cephs). MATERIALS AND METHODS: A total of 198 Japanese preadolescent children, who had skeletal Class I malocclusion and whose Lat-cephs were available at age 8 years (T0) and 10 years (T1), were allocated into the training, validation, and test phases (n = 161, n = 17, n = 20). Orthodontists and the CNN model identified 28 hard-tissue landmarks (HTL) and 19 soft-tissue landmarks (STL). The mean prediction error values were defined as 'excellent,' 'very good,' 'good,' 'acceptable,' and 'unsatisfactory' (criteria: 0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm, respectively). The degree of accurate prediction percentage (APP) was defined as 'very high,' 'high,' 'medium,' and 'low' (criteria: 90%, 70%, and 50%, respectively) according to the percentage of subjects that showed the error range within 1.5 mm. RESULTS: All HTLs showed acceptable-to-excellent mean PE values, while the STLs Pog', Gn', and Me' showed unsatisfactory values, and the rest showed good-to-acceptable values. Regarding the degree of APP, HTLs Ba, ramus posterior, Pm, Pog, B-point, Me, and mandibular first molar root apex exhibited low APPs. The STLs labrale superius, lower embrasure, lower lip, point of lower profile, B', Pog,' Gn' and Me' also exhibited low APPs. The remainder of HTLs and STLs showed medium-to-very high APPs. CONCLUSION: Despite the possibility of using the CNN model to predict growth, further studies are needed to improve the prediction accuracy in HTLs and STLs of the chin area.

2.
Front Cardiovasc Med ; 10: 1258890, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38155993

RESUMEN

Introduction: Sudden cardiac arrest is a major cause of morbidity and mortality worldwide and remains a major public health problem for which better non-invasive prediction tools are needed. Primary preventive therapies, such as implantable cardioverter defibrillators, are not personalized and not predictive. Most of these devices do not deliver life-saving therapy during their lifetime. The individual relationship between fatal arrhythmias and cardiac function abnormalities in predicting cardiac death risk has rarely been explored. Methods: We retrospectively analyzed the measurements at rest for 191 patients with acute chest pain (ACP) magnetocardiographically. Our recently introduced analyses are able to detect inhomogeneities of the depolarization and repolarization. Moreover, electrically silent phenomena-intracellular ionic currents as well as vortex currents-can be measured and quantified. All included ACP patients were recruited in 2009 at Yonsei University Hospital and were followed up until 2022. Results: During half of the follow-up period (6.5 years), 11 patients died. Out of all the included nine clinical, eight magnetocardiographical, and nine newly introduced magnetoionographical parameters we tested in this study, three parameters revealed themselves to be outstanding at predicting death: heart rate-corrected QT (QTc) prolongation, depression of repolarization current IKr + IKs, and serum creatinine (all significant in Cox regression, p < 0.05). They clearly predicted cardiac death over the 6.5 years duration (sensitivity 90.9%, specificity 85.6%, negative predictive accuracy 99.4%). Cardiac death risk was more than ninefold higher in patients with low repolarization reserve and QTc prolongation in comparison with the remaining patients with ACP (p < 0.001). The non-parametric Kaplan-Meier statistics estimated significantly lower survival functions from their lifetime data (p < 0.001). Discussion: To the best of our knowledge, these are the first data linking magnetocardiographical and magnetoionographical parameters and subsequent significant fatal events in people, suggesting structural and functional components to clinical life-threatening ventricular arrhythmogenesis. The findings support investigation of new prevention strategies and herald those new non-invasive techniques as complementary risk stratification tools.

3.
Lymphology ; 56(1): 27-39, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38019877

RESUMEN

Acupuncture is a potential therapy for breast cancer-related lymphedema (BCRL). Despite a recent meta-analysis on efficacy, data on acupuncture safety in BCRL are lacking. Current clinical guidelines recommend avoiding needling in the upper extremity affected by lymph node dissection. We undertook a systematic review focusing on acupuncture safety and treatment protocols in clinical trials for BCRL. Literature searches were conducted in PubMed, Ovid, CINAHL, and Cochrane library. Eight clinical trials on acupuncture for BCRL were analyzed. The Standards of Acupuncture intervention (STRICTA 2010) and Cochrane risk of bias (RoB2 2019) were applied to assess methods for acupuncture interventions within Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework. Quantity and severity of adverse events (AE) were reviewed. A total of 189 subjects participated in 8 clinical trials with 2965 acupuncture treatments. No serious adverse events (SAE) were reported regardless of treatment laterality or protocol, with only a single grade 2 skin infection in 2,965 total treatments (0.034%), including 1,165 bilateral and 225 ipsilateral treatments. Our comprehensive review of clinical trials of acupuncture for BCRL demonstrated no significant adverse events in 2,965 treatments, including 1,390 in the affected limb. An approach for routine integration of acupuncture into BCRL maintenance therapy is proposed.


Asunto(s)
Terapia por Acupuntura , Linfedema del Cáncer de Mama , Neoplasias de la Mama , Linfedema , Humanos , Femenino , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/terapia , Linfedema del Cáncer de Mama/etiología , Linfedema del Cáncer de Mama/terapia , Terapia por Acupuntura/efectos adversos , Terapia por Acupuntura/métodos , Extremidad Superior , Linfedema/etiología , Linfedema/terapia
5.
Technol Cancer Res Treat ; 22: 15330338231175781, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37226496

RESUMEN

BACKGROUND: To develop a fully automated in-house gamma analysis software for the "Cheese" phantom-based delivery quality assurance (QA) of helical tomotherapy plans. METHODS: The developed in-house software was designed to automate several procedures, which need to be manually performed using commercial software packages. The region of interest for the analysis was automatically selected by cropping out film edges and thresholding dose values (>10% of the maximum dose). The film-measured dose was automatically aligned to the computed dose using an image registration algorithm. An optimal film scaling factor was determined to maximize the percentage of pixels passing gamma (gamma passing rate) between the measured and computed doses (3%/3 mm criteria). This gamma analysis was repeated by introducing setup uncertainties in the anterior-posterior direction. For 73 tomotherapy plans, the gamma analysis results using the developed software were compared to those analyzed by medical physicists using a commercial software package. RESULTS: The developed software successfully automated the gamma analysis for the tomotherapy delivery quality assurance. The gamma passing rate (GPR) calculated by the developed software was higher than that by the clinically used software by 3.0%, on average. While, for 1 of the 73 plans, the GPR by the manual gamma analysis was higher than 90% (pass/fail criteria), the gamma analysis using the developed software resulted in fail (GPR < 90%). CONCLUSIONS: The use of automated and standardized gamma analysis software can improve both the clinical efficiency and veracity of the analysis results. Furthermore, the gamma analyses with various film scaling factors and setup uncertainties will provide clinically useful information for further investigations.


Asunto(s)
Radioterapia de Intensidad Modulada , Humanos , Programas Informáticos , Algoritmos , Rayos gamma , Fantasmas de Imagen
6.
Chemosphere ; 331: 138780, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37142101

RESUMEN

In this study, a mixed phase ZnSn(OH)6/ZnSnO3 photocatalyst was synthesized by calcining ZHS nanostructures via rapid thermal annealing (RTA) process. The composition ratio of ZnSn(OH)6/ZnSnO3 was controlled by changing the duration of the RTA process. The obtained mixed-phase photocatalyst was characterized by X-ray diffraction, field emission scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance spectroscopy, ultraviolet photoelectron spectroscopy, photoluminescence, and physisorption analysis. Results showed that ZnSn(OH)6/ZnSnO3 photocatalyst obtained by calcining ZHS at 300 °C for 20 sec displayed the best photocatalytic performance under UVC light illumination. Under optimized reaction conditions, ZHS-20 (0.125 g) demonstrated nearly complete removal (>99%) of MO dye in 150 min. Scavenger study revealed the predominant role of OH• in photocatalysis. The enhanced photocatalytic activity of the ZnSn(OH)6/ZnSnO3 composites was mainly ascribed to the photosensitization of ZHS by ZTO and effective electron-hole separation at the ZnSn(OH)6/ZnSnO3 heterojunction interface. It is expected that this study will provide new research input for the development of photocatalyst through thermal annealing-induced partial phase transformation.


Asunto(s)
Luz , Nanoestructuras , Microscopía Electrónica de Rastreo , Nanoestructuras/química
7.
J Acoust Soc Am ; 153(5): 3065, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37222575

RESUMEN

When using a sparse array, locating the target signal of a high-frequency component is difficult. Although forecasting the direction in a sparse situation is challenging, the frequency-wavenumber (f-k) spectrum can simultaneously determine the direction and frequency of the analyzed signal. The striation of the f-k spectrum shifts along the wavenumber axis in a sparse situation, which reduces the spatial resolution required to determine the target's direction using the f-k spectrum. In this study, f-k spectra of a high-frequency signal were used for near-field source localization. Snapping shrimp sounds (5-24 kHz) from SAVEX15 (a shallow-water acoustic variability experiment conducted in May 2015) were used as the data source, and a simulation was used to evaluate the proposed method. Beam steering was performed before creating the f-k spectrum to improve spatial resolution. We found that the spatial resolution was improved, and the location of the sound source could be determined when a signal with beam steering was utilized. The shrimp sound from SAVEX15, a near-field broadband signal, was used to determine the shrimp's location (range, 38 m; depth, 100 m) and the tilt of the vertical line array. These results suggest that the proposed analysis helps to accurately estimate the location of sound source.

8.
Neurol India ; 71(1): 9-19, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36861567

RESUMEN

Background: Post-traumatic stress disorder (PTSD) frequently follows neurological disorders such as non-traumatic subarachnoid hemorrhage (SAH) and has debilitating consequences. Objective: The aim of this systematic review was the critical appraisal of the literature on the frequency, severity, and temporal progression of PTSD in patients with SAH, the etiology of PTSD, and its effect on patients' quality of life (QoL). Material and Methods: Studies were obtained from three databases: PubMed EMBASE, PsycINFO, and Ovid Nursing. The inclusion criteria were English-language studies on adults (defined as at least 18 years of age) in which ≥10 of the participants received a diagnosis of PTSD following SAH. Applying these criteria, 17 studies (N = 1,381) were included. Results: Between 1% and 74% of the participants in each study had PTSD, with a weighted average of 36.6% across all studies. Post-SAH PTSD showed significant correlations with premorbid psychiatric disorders, neuroticism, and maladaptive coping styles. The risk of PTSD was also higher in participants with comorbid depression and anxiety. Stress related to post-ictal events and fear of recurrence were associated with PTSD. However, the risk of PTSD was lower in participants with effective social support networks. The participants' QoL was negatively affected by PTSD. Conclusions: This review highlights the high occurrence of PTSD in SAH patients. The temporal progression and chronicity of post-SAH PTSD warrant further research, as do its neuroanatomical and neurochemical correlates. We call for more randomized controlled trials investigating these aspects.


Asunto(s)
Trastornos por Estrés Postraumático , Hemorragia Subaracnoidea , Adulto , Humanos , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/etiología , Calidad de Vida , Hemorragia Subaracnoidea/complicaciones , Ansiedad , Lenguaje
9.
AJNR Am J Neuroradiol ; 44(1): 65-69, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36521964

RESUMEN

BACKGROUND AND PURPOSE: A cardiogenic embolus could reach the posterior circulation through the right vertebral artery because of a relatively larger diameter in cases of left vertebral artery hypoplasia. Hence, we investigated whether left vertebral artery hypoplasia is associated with cardiac embolisms with atrial fibrillation in the posterior circulation and its functional outcomes. MATERIALS AND METHODS: In this monocentric retrospective study, patients with acute cardioembolic stroke with atrial fibrillation were enrolled and underwent CT or neck MRA, which visualized the aortic arch and subclavian arteries. The laterality and size of vertebral artery hypoplasia were recorded. Posterior circulation stroke, basilar artery occlusion, and the functional outcomes after 3 months were investigated. RESULTS: This study included 407 patients; the patients with left vertebral artery hypoplasia experienced a higher rate of posterior circulation stroke (19 versus 73; 42.2% versus 20.2%; P = .001) and basilar artery occlusion (5 versus 10; 11.1% versus 2.8%; P = .005) than the patients without left vertebral artery hypoplasia. Multivariate analysis revealed that left vertebral artery hypoplasia showed an association with lower odds of achieving a good functional outcome 3 months after the stroke (OR = 0.4; 95% CI, 0.2-0.9; P = .027). CONCLUSIONS: Patients with cardioembolic stroke and left vertebral artery hypoplasia had posterior circulation stroke, basilar artery occlusion, and poor functional outcomes after 3 months.


Asunto(s)
Arteriopatías Oclusivas , Fibrilación Atrial , Accidente Cerebrovascular Embólico , Accidente Cerebrovascular , Insuficiencia Vertebrobasilar , Humanos , Arteria Vertebral/diagnóstico por imagen , Accidente Cerebrovascular Embólico/complicaciones , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico por imagen , Aorta Torácica , Estudios Retrospectivos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Arteriopatías Oclusivas/complicaciones , Insuficiencia Vertebrobasilar/complicaciones , Insuficiencia Vertebrobasilar/diagnóstico por imagen
10.
Clin Oncol (R Coll Radiol) ; 35(1): e10-e19, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35918275

RESUMEN

AIMS: Objective evaluation of radiation dermatitis is important for analysing the correlation between the severity of radiation dermatitis and dose distribution in clinical practice and for reliable reporting in clinical trials. We developed a novel radiation dermatitis segmentation system based on convolutional neural networks (CNNs) to consistently evaluate radiation dermatitis. MATERIALS AND METHODS: The radiation dermatitis segmentation system is designed to segment the radiation dermatitis occurrence area using skin photographs and skin-dose distribution. A CNN architecture with a dilated convolution layer and skip connection was designed to estimate the radiation dermatitis area. Seventy-three skin photographs obtained from patients undergoing radiotherapy were collected for training and testing. The ground truth of radiation dermatitis segmentation is manually delineated from the skin photograph by an experienced radiation oncologist and medical physicist. We converted the skin photographs to RGB (red-green-blue) and CIELAB (lightness (L∗), red-green (a∗) and blue-yellow (b∗)) colour information and trained the network to segment faint and severe radiation dermatitis using three different input combinations: RGB, RGB + CIELAB (RGBLAB) and RGB + CIELAB + skin-dose distribution (RGBLAB_D). The proposed system was evaluated using the Dice similarity coefficient (DSC), sensitivity, specificity and normalised Matthews correlation coefficient (nMCC). A paired t-test was used to compare the results of different segmentation performances. RESULTS: Optimal data composition was observed in the network trained for radiation dermatitis segmentation using skin photographs and skin-dose distribution. The average DSC, sensitivity, specificity and nMCC values of RGBLAB_D were 0.62, 0.61, 0.91 and 0.77, respectively, in faint radiation dermatitis, and 0.69, 0.78, 0.96 and 0.83, respectively, in severe radiation dermatitis. CONCLUSION: Our study showed that CNN-based radiation dermatitis segmentation in skin photographs of patients undergoing radiotherapy can describe radiation dermatitis severity and pattern. Our study could aid in objectifying the radiation dermatitis grading and analysing the reliable correlation between dosimetric factors and the morphology of radiation dermatitis.


Asunto(s)
Aprendizaje Profundo , Radiodermatitis , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Radiodermatitis/diagnóstico , Radiodermatitis/etiología , Planificación de la Radioterapia Asistida por Computador/métodos
11.
Nat Commun ; 13(1): 7901, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36550110

RESUMEN

High-pressure electrical resistivity measurements reveal that the mechanical deformation of ultra-hard WB2 during compression induces superconductivity above 50 GPa with a maximum superconducting critical temperature, Tcof 17 K at 91 GPa. Upon further compression up to 187 GPa, the Tcgradually decreases. Theoretical calculations show that electron-phonon mediated superconductivity originates from the formation of metastable stacking faults and twin boundaries that exhibit a local structure resembling MgB2 (hP3, space group 191, prototype AlB2). Synchrotron x-ray diffraction measurements up to 145 GPa show that the ambient pressure hP12 structure (space group 194, prototype WB2) continues to persist to this pressure, consistent with the formation of the planar defects above 50 GPa. The abrupt appearance of superconductivity under pressure does not coincide with a structural transition but instead with the formation and percolation of mechanically-induced stacking faults and twin boundaries. The results identify an alternate route for designing superconducting materials.

12.
JASA Express Lett ; 2(5): 056001, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-36154075

RESUMEN

In long-range underwater communication, conventional time reversal processing (CTRP) is used to mitigate the distortion caused by multipath and temporal spreading. However, signals produced by marine animals can contaminate communication signals. Impulsive signals, such as dolphin sonar clicks, have wide bandwidths and short pulse durations, making it difficult to isolate the communication signal. This letter proposes a method to cancel these sounds by estimating the Green's function of marine animal clicks and applying adaptive time reversal processing (ATRP). The effectiveness of the click nulling was verified by comparing the performances of CTRP and ATRP with seagoing experimental data.


Asunto(s)
Delfines , Ecolocación , Animales , Comunicación , Sonido , Espectrografía del Sonido
13.
Int J Tuberc Lung Dis ; 26(6): 509-515, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35650694

RESUMEN

BACKGROUND: We investigated the feasibility of early line-probe assay (LPA) using remnant DNA of Mycobacterium tuberculosis from polymerase chain reaction (PCR) test.METHODS: M. tuberculosis DNA specimens with cycle threshold (Ct) values reported and collected from patients with known results for both LPA with culture isolates and phenotype drug susceptibility testing (pDST) were selected. The diagnostic performance of DNA-based LPA according to the Ct value was investigated.RESULTS: A total of 143 respiratory specimens were included. For isoniazid resistance, the accuracy in subgroups with Ct value <25, 25-29 and ≥29 was respectively 96.8%, 65.7% and 13.3%. For rifampicin resistance, accuracy in subgroups with Ct values <29 and ≥29 was respectively 87.8% and 13.3%. When compared to the pDST results, sensitivity, specificity, positive predictive value and negative predictive value in specimens with Ct values <25 was respectively 1.00 (95% CI 0.69-1.00), 0.95 (95% CI 0.76-1.00), 0.91 (95% CI 0.59-1.00) and 1.00 (95% CI 0.83-1.00) for isoniazid resistance. For rifampicin resistance, corresponding values in subgroups with Ct values <29 were respectively 0.89 (95% CI 0.52-1.00), 0.98 (95% CI 0.91-1.00), 0.80 (95% CI 0.50-0.94) and 0.99 (95% CI 0.92-1.00).CONCLUSIONS: DNA-based early LPA with remnant DNA from respiratory samples was feasible and accurate when the Ct values were low.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis Pulmonar , ADN , Humanos , Isoniazida/farmacología , Isoniazida/uso terapéutico , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/genética , Rifampin/farmacología , Rifampin/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/tratamiento farmacológico
14.
Domest Anim Endocrinol ; 81: 106745, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35716584

RESUMEN

Heat stress adversely affects intestinal barrier integrity ranging from minor enterocyte injury to fatal inflammatory heat shocks. The current review discusses the physiological mechanisms of the adaptive response of poultry and the nutritional interventions to improve intestinal integrity during heat stress. There are several possible metabolic mechanisms of protection including stress adaptation signaling pathways, blood flow, intestinal barrier permeability, epithelial cell proliferation, antioxidant status, microbiota composition, expression of heat shock proteins, inflammatory responses, and energy metabolism. The current review discusses the methods of intestinal permeability determination in order to estimate the extent of damage in the farm. There is a lack of knowledge about the nutritional strategies and the interaction between nutrients to reduce intestinal barrier damage and elucidate mechanisms in heat stress.


Asunto(s)
Trastornos de Estrés por Calor , Aves de Corral , Animales , Trastornos de Estrés por Calor/veterinaria , Respuesta al Choque Térmico , Mucosa Intestinal/metabolismo , Intestinos/fisiología
15.
Eur Rev Med Pharmacol Sci ; 26(9): 3342-3350, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35587087

RESUMEN

OBJECTIVE: Multisystem inflammatory syndrome in children (MIS-C) can occur in association with coronavirus disease 2019 (COVID-19). It is not easy to differentiate MIS-C from severe COVID-19 or Kawasaki disease based on symptoms. The aim of this study was to describe the clinical and laboratory characteristics of MIS-C. PATIENTS AND METHODS: We searched PubMed/Medline for case series and reports of MIS-C published until June 20, 2020. From a total of nine articles involving 45 cases, various clinical and laboratory data were extracted. Each target case was evaluated by using different diagnostic criteria. RESULTS: The average age at onset of MIS-C was 8.6 years. In 80% of cases, the age of patients ranged from 5 to 15 years. Fever (100%) and shock (82%) were the most common presenting symptoms. Sixty percent of cases met the diagnostic criteria for typical or atypical Kawasaki disease. Biomarkers indicative of inflammation, coagulopathy, or cardiac injury were characteristically elevated as follows: ferritin (mean: 1,061 ng/mL), CRP (217 mg/L), ESR (69 mm/hr), IL-6 (214.8 pg/mL), TNFα (63.4 pg/mL), D-dimer (3,220 ng/mL), PT (15.5 s), troponin I (1,006 ng/L), and BNP (12,150 pg/mL). Intravenous immunoglobulin was administered in all target cases, and inotropic agents were commonly used as well. No case of death was observed. CONCLUSIONS: This study demonstrated that MIS-C is a serious condition that presents with fever, rash, as well as cardiovascular and gastrointestinal symptoms. Although it is challenging to differentiate MIS-C from Kawasaki disease or severe COVID-19, initiation of appropriate treatments through early diagnosis is warranted.


Asunto(s)
COVID-19 , Síndrome Mucocutáneo Linfonodular , Adolescente , COVID-19/complicaciones , COVID-19/diagnóstico , Niño , Preescolar , Fiebre/diagnóstico , Humanos , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , SARS-CoV-2 , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico
16.
J Phys Condens Matter ; 34(26)2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35385840

RESUMEN

The nanoscale patterns produced by bombardment of the (100) surface of silicon with a 2 keV Kr ion beam are investigated both experimentally and theoretically. In our experiments, we find that the patterns observed at high ion fluences depend sensitively on the angle of incidence Θ. For Θ values between 74° and 85°, we observe five decidedly different kinds of morphologies, including triangular nanostructures traversed by parallel-mode ripples, long parallel ridges decorated by short-wavelength ripples, and a remarkable mesh-like morphology. In contrast, only parallel-mode ripples are present for low ion fluences except for Θ = 85°. Our simulations show that triangular nanostructures that closely resemble those in our experiments emerge if a linearly dispersive term and a conserved Kuramoto-Sivashinsky nonlinearity are appended to the usual equation of motion. We find ridges traversed by ripples, on the other hand, in simulations of the Harrison-Pearson-Bradley equation (Harrisonet al2017Phys. Rev.E96032804). For Θ = 85°, the solid surface is apparently stable and simulations of an anisotropic Edwards-Wilkinson equation yield surfaces similar to those seen in our experiments. Explaining the other two kinds of patterns we find in our experiments remains a challenge for future theoretical work.

17.
Eur J Appl Physiol ; 122(6): 1441-1457, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35303160

RESUMEN

OBJECTIVES: Examine the acute effects (pre-, during, post-intervention) of two different intensities of aerobic exercise or rest on autonomic, oculomotor, and vestibular function and symptom burden in patients with a recent sport-related concussion (SRC) and compare their responses to sex-matched, age-stratified, non-concussed (HEALTHY) student-athletes. METHODS: Student-athletes between the ages of 13 and 18 that presented to the sports medicine clinic within Day 3-7 post-SRC and from local schools were recruited for a randomized controlled trial (RCT). The participants were administered the Vestibular/Ocular Motor Screening (VOMS), King-Devick (K-D), and Post-Concussion Symptom Scale (PCSS) before and after the intervention. Heart rate variability (HRV) and mean arterial pressure (MAP) were collected before, during, and after the intervention. The intervention was either a single, 20-min session of treadmill walking at 40% (40HR) or 60% of age-predicted max heart rate (60HR), or seated, rest (NOEX). RESULTS: 30 participants completed the intervention with the SRC group treated 4.5 ± 1.3 days post-injury. Pre-exercise HRV and MAP were significantly different (p's < 0.001) during treatment but returned to pre-exercise values within 5 min of recovery in both the SRC and HEALTHY groups. Both the SRC and HEALTHY groups exhibited similar reductions pre- to post-intervention for symptom severity and count (p's < 0.05), three VOMS items (p's < 0.05) but not K-D time. CONCLUSIONS: To date, this is the first adolescent RCT to report the acute, systemic effects of aerobic exercise on recently concussed adolescent athletes. The interventions appeared safe in SRC participants, were well-tolerated, and provided brief therapeutic benefit. TRIAL REGISTRATION: Clinicaltrials.gov Identifier NCT03575455.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , Adolescente , Atletas , Traumatismos en Atletas/terapia , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/terapia , Ejercicio Físico , Humanos , Estudiantes
19.
J Mol Cell Cardiol ; 166: 74-90, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35227737

RESUMEN

Myocardial infarction (MI) produces acute changes in strain and stiffness within the infarct that can affect remote areas of the left ventricle (LV) and drive pathological remodeling. We hypothesized that intramyocardial delivery of a hydrogel within the MI region would lower wall stress and reduce adverse remodeling in Yorkshire pigs (n = 5). 99mTc-Tetrofosmin SPECT imaging defined the location and geometry of induced MI and border regions in pigs, and in vivo and ex vivo contrast cine computed tomography (cineCT) quantified deformations of the LV myocardium. Serial in vivo cineCT imaging provided data in hearts from control pigs (n = 3) and data from pigs (n = 5) under baseline conditions before MI induction, post-MI day 3, post-MI day 7, and one hour after intramyocardial delivery of a hyaluronic acid (HA)-based hydrogel with shear-thinning and self-healing properties to the central infarct area. Isolated, excised hearts underwent similar cineCT imaging using an ex vivo perfused heart preparation with cyclic LV pressurization. Deformations were evaluated using nonlinear image registration of cineCT volumes between end-diastole (ED) and end-systole (ES), and 3D Lagrangian strains were calculated from the displacement gradients. Post-MI day 3, radial, circumferential, maximum principal, and shear strains were reduced within the MI region (p < 0.04) but were unchanged in normal regions (p > 0.6), and LV end diastolic volume (LV EDV) increased (p = 0.004), while ejection fraction (EF) and stroke volume (SV) decreased (p < 0.02). Post-MI day 7, radial strains in MI border zones increased (p = 0.04) and dilation of LV EDV continued (p = 0.052). There was a significant negative linear correlation between regional radial and maximum principal/shear strains and percent infarcted tissue in all hearts (R2 > 0.47, p < 0.004), indicating that cineCT strain measures could predict MI location and degree of injury. Post-hydrogel day 7 post-MI, LV EDV was significantly reduced (p = 0.009), EF increased (p = 0.048), and radial (p = 0.021), maximum principal (p = 0.051), and shear strain (p = 0.047) increased within regions bordering the infarct. A smaller strain improvement within the infarct and normal regions was also noted on average along with an improvement in SV in 4 out of 5 hearts. CineCT provides a reliable method to assess regional changes in strains post-MI and the therapeutic effects of intramyocardial hydrogel delivery.


Asunto(s)
Ventrículos Cardíacos , Infarto del Miocardio , Animales , Ventrículos Cardíacos/patología , Hidrogeles/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/terapia , Porcinos , Nanomedicina Teranóstica , Remodelación Ventricular
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