Outcomes and Complications of Endovascular Mechanical Thrombectomy in the Treatment of Acute Posterior Circulation Occlusions: A Systematic Review.

BACKGROUND: The use of thrombectomy in the treatment for acute ischemic stroke (AIS) affecting the anterior circulation is well established. Comparatively, fewer data exist on the effectiveness of these techniques in treating posterior circulation occlusions. This review analyzes and reports on the usefulness and outcomes of emergent thrombectomy in large-vessel occlusions affecting the posterior circulation. METHODS: A literature review was performed to identify all studies of patients with AIS in the posterior circulation who underwent endovascular mechanical thrombectomy (EMT) with stent retrievers and/or aspiration devices that were reported between January 1, 2015 and February 12, 2019. Favorable outcomes were defined as a modified Rankin Scale (mRS) score 0-2 at 3 months follow-up. Successful reperfusion was defined as modified Thrombolysis in Cerebral Infarction score of 2b-3. RESULTS: Twenty-five studies, comprising 1612 EMT-treated patients with posterior circulation AIS, were included in this analysis. The median presenting National Institutes of Health Stroke Scale score was 20.9 (range, 10.5-34). Favorable outcomes at 3 months follow-up were observed in 38% of patients (range, 16%-75%) and a mortality of 30% (range, 4%-64%). Successful reperfusion was achieved in 86% of cases (range, 62%-100%). CONCLUSIONS: In patients with AIS caused by large-vessel occlusion of the posterior circulation, successful reperfusion can be achieved via EMT, with approximately a third of these patients achieving a good functional outcome. However, with similar proportions of treated patients experiencing significant morbidity or mortality, respectively, there is urgent need for additional studies to identify predictive or modifiable factors for a positive outcome.

Percepción de esfuerzo y cambios en el rendimiento producidos por una sesión de entrenamiento en circuito en hipoxia o normoxia / Rating of perceived exertion and physical performance changes after one circuit training session in hypoxia or normoxia

El objetivo del presente estudio fue analizar los cambios en el rendimiento de fuerza y en la percepción de esfuerzo (RPE) producidos por una sesión de entrenamiento de fuerza en circuito en hipoxia (FiO2 = 0,16) o normoxia (FiO2 = 0,21). Once deportistas entrenados en fuerza realizaron dos sesiones de entrenamiento en circuito de forma aleatoria en hipoxia o normoxia. Tres días después de una primera sesión de familiarización en la que se determinaron las cargas, se llevó a cabo la primera sesión de entrenamiento. La última sesión se llevó a cabo 72 horas después. La sesión consistió en dos bloques de tres ejercicios (bloque 1: press banca, peso muerto y curl de bíceps; bloque 2: media sentadilla, press francés y extensión de tobillos) realizando 3 series de 6 repeticiones al 6RM con un descanso de 35 segundos entre ejercicio, 3 minutos entre serie y 5 minutos entre bloques. Se analizó la percepción de esfuerzo (RPE) después de cada serie y los valores medios y máximos de velocidad, aceleración, fuerza y potencia, así como los tiempos obtenidos hasta la máxima velocidad y la máxima potencia en media sentadilla y press de banca. Los resultados no muestran diferencias significativas en el RPE entre condiciones. Se observan diferencias significativas entre ambas condiciones en la primera serie de sentadilla en la variable aceleración pico (normoxia = 2,9 ± 0,7 m/s2 ; hypoxia = 2,2 ± 1,1 m/s2 ; p = 0,037) y en la variable potencia pico (normoxia = 1577,1 ± 587,5 W; hypoxia = 1227.2 ± 636,3 W; p = 0,039). En conclusión, la adición de hipoxia a la sesión de entrenamiento de fuerza afecta a la potencia y a la aceleración pico desarrollada en el ejercicio de sentadilla pero no modifica la percepción de esfuerzo que tiene el deportista

The aim of this study was to analyze the rating perceived exertion and physical performance changes after one session of circuit training in hypoxia (FiO2 = 0.16) or normoxia (FiO2 = 0.21). Eleven resistance-trained young male subjects participated in the study. They performed two circuit training session (hypoxia or normoxia) in randomized order. Three days before the first training session, a familiarization and 6RM test session was performed. After 72 hours of rest, the subjects performed the last training session. The circuit training consisted of two blocks of three exercises (Block 1: bench press, deadlift and elbow flexion; Block 2: half-squat, triceps extension, and ankle extension). Each exercise was performed at 6RM. Rest periods lasted for 35 s between exercises, 3 min between sets, and 5 min between blocks. Rating of perceived exertion (RPE) and peak and mean force, velocity, power and acceleration and time to perform peak power and velocity were determined during all the sets half-squat and bench press exercises. No differences were observed in RPE values between hypoxia and normoxia. Moreover, significant differences were observed in the first trial of half squat in peak acceleration (normoxia = 2.9 ± 0.7 m/s2 ; hypoxia = 2.2 ± 1.1 m/s2 ; p = 0.037) and peak power (normoxia = 1577.1 ± 587.5 W; hypoxia = 1227.2 ± 636.3 W; p = 0.039) between hypoxia and normoxia. In conclusion, these results indicate that simulated hypoxia during circuit training exercise decreases peak power and peak acceleration but maintains rating perceived exertion of the exercise. These differences must be taken into account to avoid an excessive fatigue

Acute Physiological and Performance Responses to High-Intensity Resistance Circuit Training in Hypoxic and Normoxic Conditions.

Ramos-Campo, DJ, Rubio-Arias, JÁ, Freitas, TT, Camacho, A, Jiménez-Diaz, JF, and Alcaraz, PE. Acute physiological and performance responses to high-intensity resistance circuit training in hypoxic and normoxic conditions. J Strength Cond Res 31(4): 1040-1047, 2017-The aim of this study was to analyze physical performance and physiological variables during high-intensity resistance circuit training (HRC) with the addition of 2 levels (moderate and high) of systemic hypoxia. Twelve resistance-trained young male subjects participated in the study. After a 6 repetition maximum testing session, participants performed 3 randomized trials of HRC: normoxia (NORM: fraction of inspired oxygen [FiO2] = 0.21; ∼0 m altitude), moderate hypoxia (MH: FiO2 = 0.16; ∼2.100 m altitude), or high hypoxia (HH: FiO2 = 0.13; ∼3.800 m altitude), as controlled by a hypoxic generator. Bench press force, heart rate and heart rate variability, rating of perceived exertion, resting metabolic rate, energy cost, and countermovement jump were assessed in each session. Heart rate variability in HH was significantly lower (standard deviation of all normal NN intervals [intervals between two "normal" beats] = 111.9 vs. 86.7 milliseconds; standard deviation of the difference between consecutive NN intervals = 19.5 vs. 17.0 milliseconds; p ≤ 0.05) in comparison with NORM. There were significant differences in rating of perceived exertion between NORM and HH (11.6 vs. 13.8 points). Peak and mean force on the bench press were significantly lower (p ≤ 0.05) in HH when compared with MH (peak: 725 vs. 488 N; mean: 574 vs. 373 N). Energy cost was significantly higher (p ≤ 0.01) in both hypoxic conditions compared with NORM (NORM: 10.4; MH: 11.7; HH: 13.3 kJ·min). There were no differences between conditions in heart rate and countermovement jump variables. These results indicate that hypoxic stimuli during HRC exercise alter physical performance and physiological variables and affect how strenuous the exercise is perceived to be. High-intensity resistance circuit training in hypoxia increases the stress on the performance and physiological responses, and these differences must be taken into account to avoid an excessive overload.

Modeling of Breathy Voice Quality Using Pitch-strength Estimates.

BACKGROUND: The characteristic voice quality of a speaker conveys important linguistic, paralinguistic, and vocal health-related information. Pitch strength refers to the salience of pitch sensation in a sound and was recently reported to be strongly correlated with the magnitude of perceived breathiness based on a small number of voice stimuli. OBJECTIVE: The current study examined the relationship between perceptual judgments of breathiness and computational estimates of pitch strength based on the Aud-SWIPE (P-NP) algorithm for a large number of voice stimuli (330 synthetic and 57 natural). METHODS AND RESULTS: Similar to the earlier study, the current results confirm a strong relationship between estimated pitch strength and listener judgments of breathiness such that low pitch-strength values are associated with voices that have high perceived breathiness. Based on this result, a model was developed for the perception of breathy voice quality using a pitch-strength estimator. Regression functions derived between the pitch-strength estimates and perceptual judgments of breathiness obtained from matching task revealed a linear relationship for a subset of the natural stimuli. We then used this function to obtain predicted breathiness values for the synthetic and the remaining natural stimuli. CONCLUSIONS: Predicted breathiness values from our model were highly correlated with the perceptual data for both types of stimuli. Systematic differences between the breathiness of natural and synthetic stimuli are discussed.

The relationship between acoustic habitat, hearing and tonal vocalizations in the Antillean manatee (Trichechus manatus manatus, Linnaeus, 1758).

The Antillean manatee (Trichechus manatus manatus) is an endangered marine mammal that inhabits the Caribbean Sea and riverine systems in Central America. Their acoustic behavior is relevant for individual identification, mating and parental care. Manatees produce tonal sounds with highest energy in the second harmonic (usually 5 kHz), and their audiogram indicates sensitivity from 0.3 kHz to 90 kHz with lowest thresholds in the 16 to 18 kHz range. We recorded manatees in the San San River, a highly polluted riverine system in Panama, using a stereo array. Frequency transmission experiments were conducted in four subhabitats, categorized using riverine vegetation. Incidental interactions of manatees and small motorboats were examined. Acoustic transmission was linearly related to tonal vocalization characters: correlations were stronger in freshwater than in transition and marine environments. Two bands, 0.6 to 2 kHz and 3 to 8 kHz, attenuate similarly in all subhabitats, and these bands encompass F0 (tone) and peak frequency respectively of manatee tonal calls. Based on our data we conclude that frequency transmission depends mainly on river depth and bottom characteristics, also motorboat sounds mask signals from 3.5 kHz to 8 kHz, which overlaps the peak frequency of tonal calls. In spite of differences between acoustic transmission in subhabitats of the San San River, manatees utilize bands that transmit efficiently in all subhabitats.

A model for the prediction of breathiness in vowels.

The perception of breathiness in vowels is cued by multiple acoustic cues, including changes in aspiration noise (AH) and the open quotient (OQ) [Klatt and Klatt, J. Acoust. Soc. Am. 87(2), 820-857 (1990)]. A loudness model can be used to determine the extent to which AH masks the harmonic components in voice. The resulting "partial loudness" (PL) and loudness of AH ["noise loudness" (NL)] have been shown to be good predictors of perceived breathiness [Shrivastav and Sapienza, J. Acoust. Soc. Am. 114(1), 2217-2224 (2003)]. The levels of AH and OQ were systematically manipulated for ten synthetic vowels. Perceptual judgments of breathiness were obtained and regression functions to predict breathiness from the ratio of NL to PL (η) were derived. Results show that breathiness can be modeled as a power function of η. The power parameter of this function appears to be affected by the fundamental frequency of the vowel. A second experiment was conducted to determine if the resulting power function could estimate breathiness in a different set of voices. The breathiness of these stimuli, both natural and synthetic, was determined in a listening test. The model estimates of breathiness were highly correlated with perceptual data but the absolute predicted values showed some discrepancies.

A computational model to predict changes in breathiness resulting from variations in aspiration noise level.

Perception of breathy voice quality is cued by a number of acoustic changes including an increase in aspiration noise level (AH) and spectral slope. Changes in AH in a vowel may be evaluated through measures such as the harmonic-to-noise ratio, cepstral peak prominence (CPP), or via auditory measures such as the partial loudness of harmonic energy and loudness of aspiration noise. Although a number of experiments have reported high correlation between such measures and ratings of perceived breathiness, a formal model to predict breathiness of a vowel has not been proposed. This research describes two computational models to predict changes in breathiness resulting from variations in AH. One model uses auditory measures, whereas the other uses CPP as independent variables to predict breathiness. For both cases, a translated and truncated power function is required to predict breathiness. Some parameters in both of these models were observed to be pitch dependent. The "unified" model based on auditory measures was observed to be more accurate than one based on CPP.

A sawtooth waveform inspired pitch estimator for speech and music.

A sawtooth waveform inspired pitch estimator (SWIPE) has been developed for speech and music. SWIPE estimates the pitch as the fundamental frequency of the sawtooth waveform whose spectrum best matches the spectrum of the input signal. The comparison of the spectra is done by computing a normalized inner product between the spectrum of the signal and a modified cosine. The size of the analysis window is chosen appropriately to make the width of the main lobes of the spectrum match the width of the positive lobes of the cosine. SWIPE('), a variation of SWIPE, utilizes only the first and prime harmonics of the signal, which significantly reduces subharmonic errors commonly found in other pitch estimation algorithms. The authors' tests indicate that SWIPE and SWIPE(') performed better on two spoken speech and one disordered voice database and one musical instrument database consisting of single notes performed at a variety of pitches.

Comment on "Cepstrum pitch determination" [J. Acoust. Soc. Am. 41, 293-309 (1967)].

In a paper by A. Michael Noll [J. Acoust. Soc. Am. 41, 293-309 (1967)], the use of the cepstrum was proposed to determine the pitch of a signal. This paper shows that such a method does not work on periodic signals.

Estrés y estilos de vida condicionantes de enfermedad cardiovascular en estudiantes de la UNSAAC / Stress and conditionants life style of cardiovascular disease in students of the UNSAAC

Se realizó un estudio transversal - aleatorio con la finalidad de medir la magnitud del estrés y los estilos de vida condicionantes de enfermedad cardiovascular en 299 universitarios de la UNSAAC. La mayoría de estudiantes presentó estilos de vida condicionantes de enfermedad cardiovascular muy inadecuados. El sexo masculino, el citadino, el de mayor edad y el que más años estudia en la universidad tuvieron mas estilos de vida de riesgo para enfermar.

Prevalencia de alcoholismo y sus caracteristicas de consumo en los estudiantes de la UNSAAC / Prevalencia of alcoholism and their consumption characteristics in the students of the UNSAAC

Se realizó un estudio descriptivo en 7130 estudiantes de la Universidad Nacional de San Antonio Abad del Cusco, se aplicó una encuesta para conocer la prevalencia del alcoholismo, las características de consumo de bebidas y factores asociados a éste. Se encontró una alta prevalencia de alcoholismo y consumo de alcohol sobre todo en varones, los alumnos que trabajan y entre los que estudian más años en la universidad; la edad de inicio para los varones fue más anterior al de las mujeres; la mayoría refirió consumir tanto bebidas destiladas como fermentadas; la frecuencia de consumo predominante fue la mensual y refirieon más embriaguez entre los consumidores semanales.

EPOC: características clínicas, epidemiológicas y radiológicas en pacientes de altura - Hospital Essalud de Cusco (1987 - 1999) / COPD: clinical, epidemiological and radiological patients in height - from Cuzco EsSalud Hospital (1987 - 1999)

Realizamos un estudio descriptivo retrospectivo que comprende 12 años y 6 meses en los pacientes del programa de EPOC del Hospital EsSalud Cusco. Evaluamos 160 pacientes naturales y residentes de altura. El 62 por ciento son varones entre los 50 y 79 años; los profesionales preponderán, siendo los profesores el 78.6 por ciento. El 50.6 por ciento de los pacientes tuvieron hábito tabáquico, el 7.5 por ciento persiste fumando; el 38.7 por ciento de ellos llegaron a consumir más de 15 cig./día. El 100 por ciento de los casos estuvieron expuestos a contaminantes por combustión intradomiciliaria (humo de leño) y el 35 por ciento de los casos reporta ser fumadores pasivos. El 91.9 por ciento tuvo antecedentes de enfermedad respiratoria en su niñez y juventud; el 38.8 por ciento indican que sus familiares no tuvieron EPOC y/o asma. El 57.5 por ciento tiene ECG normal, la alteración saltante es el BIRDHH; se encontró 17 casos de poliglobulia. Existe tendencia al sobre peso. La espirometría en el 47.5 por ciento de los casos son normales al ingreso, en el control 40.4 por ciento; predomina el estadío moderado. El 80 por ciento de la radiología es compatible con bronquitis crónica, en el 17.5 por ciento es normal. La tos, espectoración blanca, dísnea y roncus son síntomas preponderantes en el 80 por ciento. Los síntomas inician en la segunda década de vida. El 56.7 por ciento no evidencia mejoría al tratamiento. El 34.4 por ciento fueron evaluados en emergencia y el 9.4 por ciento fueron hospitalizados por infecciones respiratorias.