Machine learning at the interface of structural health monitoring and non-destructive evaluation.

While both non-destructive evaluation (NDE) and structural health monitoring (SHM) share the objective of damage detection and identification in structures, they are distinct in many respects. This paper will discuss the differences and commonalities and consider ultrasonic/guided-wave inspection as a technology at the interface of the two methodologies. It will discuss how data-based/machine learning analysis provides a powerful approach to ultrasonic NDE/SHM in terms of the available algorithms, and more generally, how different techniques can accommodate the very substantial quantities of data that are provided by modern monitoring campaigns. Several machine learning methods will be illustrated using case studies of composite structure monitoring and will consider the challenges of high-dimensional feature data available from sensing technologies like autonomous robotic ultrasonic inspection. This article is part of the theme issue 'Advanced electromagnetic non-destructive evaluation and smart monitoring'.

USVSEG: A robust method for segmentation of ultrasonic vocalizations in rodents.

Rodents' ultrasonic vocalizations (USVs) provide useful information for assessing their social behaviors. Despite previous efforts in classifying subcategories of time-frequency patterns of USV syllables to study their functional relevance, methods for detecting vocal elements from continuously recorded data have remained sub-optimal. Here, we propose a novel procedure for detecting USV segments in continuous sound data containing background noise recorded during the observation of social behavior. The proposed procedure utilizes a stable version of the sound spectrogram and additional signal processing for better separation of vocal signals by reducing the variation of the background noise. Our procedure also provides precise time tracking of spectral peaks within each syllable. We demonstrated that this procedure can be applied to a variety of USVs obtained from several rodent species. Performance tests showed this method had greater accuracy in detecting USV syllables than conventional detection methods.

Training in Ultrasound for Resident Physicians in Gastroenterology: a survey and training project by the Spanish Association of Digestive Ultrasound (Asociación Española de Ecografía Digestiva - AEED).

BACKGROUND: the training program of the gastroenterology specialty that is mandatory for resident physicians, obliges them to be proficient in diagnostic and therapeutic digestive ultrasound tools. METHODOLOGY: the Asociación Española de Ecografía Digestiva (AEED) performed a survey of the 93 Departments of Gastroenterology with training programs for resident physicians in gastroenterology, in order to assess the exact situation of training in digestive ultrasound in Spain. RESULTS: only 31 of the 93 (33%) Departments of Gastroenterology were able to provide training in Digestive Ultrasound. Moreover, 33% (48 out of 148) of the residents in gastroenterology did not receive specific training in digestive ultrasound. Whereas, 31% (46 out of 148) had received some specific training, but with ample room for improvement. These deficiencies were spread throughout the Spanish regions (Autonomous Communities) in an uneven manner, with almost half totally lacking gastroenterology departments that were capable of providing digestive ultrasound training. CONCLUSIONS: there is a significant deficit of gastroenterology departments capable of providing training in digestive ultrasound to residents, causing a significant training inequality. Until this situation can be reversed, the AEED has designed a training project in digestive ultrasound aimed at providing adequate training to all residents in gastroenterology as required.

Cardiac sonography by the neonatologist: clinical usefulness and educational perspective.

OBJECTIVES: Clinicians are increasingly using cardiac sonography in clinical practice. The objectives of this study were to assess the current state of clinician-performed cardiac sonography practice in the Australia-New Zealand region, with particular reference to the scope of clinical practice and type of training offered. METHODS: A prospective cross-sectional survey was conducted, and an electronic Web-based questionnaire was e-mailed to neonatologists and advanced trainees in the region. Information was collected on respondents (demographics, clinician-performed cardiac sonography experience, and opinions), equipment use, and training frameworks. Main outcome measures ascertained were clinical use and educational perspectives. RESULTS: The overall survey response rate was 64% (113 of 176). Eighty-five percent of respondents reported that clinician-performed cardiac sonography was performed in their units, most commonly to use the physiologic information obtained in conjunction with clinical information to refine decision making. The most common clinical indication was evaluation of a hemodynamically relevant ductus arteriosus. A dedicated echocardiographic machine was available to 80% of respondents. Most respondents reported "self-directed" learning as the most common method of training. More than 85% of respondents reported having access to either on-site or off-site pediatric cardiology services. CONCLUSIONS: Widespread availability and use of clinician-performed cardiac sonography in units across the Australia-New Zealand region was noted. The need for a structured training program was identified.

Continuous scanning of a time-reversed ultrasonically encoded optical focus by reflection-mode digital phase conjugation.

Time-reversed ultrasonically encoded (TRUE) optical focusing in turbid media was previously implemented using both analog and digital phase conjugation. The digital approach, in addition to its large energy gain, can improve the focal intensity and resolution by iterative focusing. However, performing iterative focusing at each focal position can be time-consuming. Here, we show that by gradually moving the focal position, the TRUE focal intensity is improved, as in iterative focusing at a fixed position, and can be continuously scanned to image fluorescent targets in a shorter time. In addition, our setup is, to the best of our knowledge, the first demonstration of TRUE focusing using a digital phase conjugate mirror in a reflection mode, which is more suitable for practical applications.

Critical care ultrasound training: a survey of US fellowship directors.

PURPOSE: The purpose of this study is to describe the current state of bedside ultrasound use and training among critical care (CC) training programs in the United States. MATERIALS AND METHODS: This was a cross-sectional survey of all program directors for Accreditation Council for Graduate Medical Education accredited programs during the 2012 to 2013 academic year in CC medicine, surgical CC, pulmonary and critical care, and anesthesia CC. Availability, current use, and barriers to training in CC ultrasound were assessed. RESULTS: Sixty of 195 (31%; 95% confidence interval [CI], 24%-38%) program directors responded. Most of the responding programs had an ultrasound system available for use (54/60, 90%; 95% CI, 79%-96%) and identified ultrasound training as useful (59/60, 98%; 95% CI, 91%-100%) but lacked a formal curriculum (25/60, 42%; 95% CI, 29%-55%) or trained faculty (mean percentage of faculty trained in ultrasound: pulmonary and critical care, 25%; surgical CC, 33%; anesthesia CC, 20%; CC medicine, 7%), and relied on informal teaching (45/60, 77%; 95% CI, 62%-85%). Faculty with expertise (53/60, 88%; 95% CI, 77%-95%), simulation training (60/60, 100%; 95% CI, 94%-100%), establishing and meeting required number of examinations (47/60, 78%; 95% CI, 66%-88%), and regular review sessions (49/60, 82%; 95% CI, 70%-90%) were identified as necessary to improve ultrasound training. Most responding programs (32/35 91%; 95% CI, 77%-98%) without a formal curriculum plan to create one in the next 5 years. CONCLUSIONS: This study identified deficiencies in current training, suggesting a need for a formal curriculum for bedside ultrasound training in CC fellowship programs.

Ultrasonic characterization of the fat source and composition of formulated dry-cured meat products.

The aim of this work was to test the feasibility of using ultrasonic measurements to estimate the fat content and identify the fat sources used in formulated dry-cured pork meat products. For that purpose, dry-cured sausages were prepared using different fat sources (two Iberian pork backfats, Iberian lard, and sunflower oil) and contents (fat content from 3% to 17% wet basis) and characterized by measuring the ultrasonic velocity (at 2 degrees C, 6 degrees C, 10 degrees C, 15 degrees C, 20 degrees C, and 25 degrees C), fatty acid profile, thermal behavior, and composition. The fatty acid composition affected the melting behavior of the sausages, which also involved different ultrasonic velocities, depending on the fat source used for the sausage formulation. Significant (p < 0.05) linear relationships were established between the ultrasonic velocity and the percentage of melted fat, by means of which the sausage batches were differentiated according to the fat source used. The ultrasonic velocity temperature dependence allowed the determination of the fat content (explained variance 96.1%) by measuring the ultrasonic velocity in the dry-cured sausages at 2 degrees C and 25 degrees C and using a semi-empirical equation. Therefore, the ultrasonic measurements could be considered as a reliable tool for the characterization and differentiation of formulated dry-cured meat products with different fat sources and contents.

Automating ultrasonic vocalization analyses: the WAAVES program.

BACKGROUND: Human emotion is a crucial component of drug abuse and addiction. Ultrasonic vocalizations (USVs) elicited by rodents are a highly translational animal model of emotion in drug abuse studies. A major roadblock to comprehensive use of USV data is the overwhelming burden to attain accurate USV assessment in a timely manner. One of the most accurate methods of analyzing USVs, human auditory detection with simultaneous spectrogram inspection, requires USV sound files to be played back 4% normal speed. NEW METHOD: WAAVES (WAV-file Automated Analysis of Vocalizations Environment Specific) is an automated USV assessment program utilizing MATLAB's Signal and Image Processing Toolboxes in conjunction with a series of customized filters to separate USV calls from background noise, and accurately tabulate and categorize USVs as flat or frequency-modulated (FM) calls. In the current report, WAAVES functionality is demonstrated by USV analyses of cocaine self-administration data collected over 10 daily sessions. RESULTS: WAAVES counts are significantly correlated with human auditory counts (r(48)=0.9925; p<0.001). Statistical analyses used WAAVES output to examine individual differences in USV responses to cocaine, cocaine-associated cues and relationships between USVs, cocaine intake and locomotor activity. COMPARISON WITH EXISTING METHOD: WAAVES output is highly accurate and provides tabulated data in approximately 0.3% of the time required when using human auditory detection methods. CONCLUSIONS: The development of a customized USV analysis program, such as WAAVES streamlines USV assessment and enhances the ability to utilize USVs as a tool to advance drug abuse research and ultimately develop effective treatments.

Quistes del colédoco en adultos: Estudio de dos casos y revisión de la literatura / Chole dochal cysts in adults: study of two cases and literature review

La finalidad de este trabajo en la rareza de la entidad clínica y tratar de determinar la incidencia en nuestro principal centro hospitalario. Hasta el momento el total de la causistica en nuestro país no sobrepasa los 30 casos, y en una revisión que comprende 12 años (1980-1992) a nivel de nuestro centro (H.U.L.A) solo se reportaron dos casos. Presentamos dos casos de quistes del colédoco en dos adultos de sexo femenino con edades respectivas 20 y 22 años, portadoras de quistes del colédoco tipo I, las cuales mostraron la triada clásica de dolor en hipocondrio derecho, ictericia y masa intraabdominal, planteándose como tratamiento la exeresis de los quistes y hepaticoyeyunostomía en Y de Roux, observándose evolución satisfactoria

Correlación histopatológica de los hallazgos al tacto rectal y al ultrasonido prostático / Hystopathologic correlation between prostatic digital examination and transrectal ultrasound

Se presentan los resultados obtenidos en 138 pacientes que fueron estudiados desde el punto de vista prostático, practicándoseles el Tacto Rectal (TR), Ultrasonido Transrectal (USTR) y estudio histopatológico a través de biopsia guiada con USTR y Resección Transuretral (RTU). Se tabulan los hallazgos encontrados con estos procedimientos, encontrando una superioridad del USTR que presenta ausencia de falsos negativos, mientras que el TR tiene 15 casos. Esto hace que la sensibilidad y el valor de predicción negativo del USTR sea superior al TR. Existe un alto número de falsos positivos en el USTR, el cual se hace menos evidente en el último grupo de pacientes tratados, hecho que consideramos está en relación con la mayor experiencia del autor

Utilization of diagnostic ultrasound in a controlled setting.

To appreciate the number of ultrasound studies of different types done within a population consisting of both rural and urban persons, a questionnaire was sent to all ultrasound facilities within the Canadian Province of British Columbia. All of the questionnaires were returned, providing complete data for 1978, 1979, and 1980. In addition to data on numbers of ultrasound studies (broken into various categories), the number of sonographers and sonologists were also analyzed. The results show an 87% increase from 1978 to 1980 in the number of studies, and, in 1980, a rate of 37 ultrasound procedures per thousand population per year (52 per thousand in the largest urban area in the province). The complete data and a discussion of the unique features of the British Columbia experience are presented.

Intrauterine transfusion utilizing ultrasound.

Thirty-seven intrauterine transfusions were performed on 17 severely Rh-sensitized women utilizing a technique entirely dependent upon ultrasound for needle insertion. The neonatal survival rate was 71%; 57% (4 of 7) of the hydropic fetuses and 80% (8 of 10) of those with no antenatal evidence of ascites survived. Twenty-five percent of the 12 neonatal survivors received their initial transfusion at 26.5 weeks or earlier. These results are comparable to the best of those in series relying on x-ray or fluoroscopy techniques for performing the procedure. Intrauterine transfusion continues to play an essential therapeutic role in the management of the severely affected erythroblastotic fetus. It is recommended that techniques relying on ultrasound be utilized in preference to those using x-ray to reduce radiation exposure in utero.

The diagnostic process: a comparison of scanning techniques.

In choosing between various scanning techniques the factors to be considered include availability, cost, the type of equipment, the expertise of the medical and technical staff, and the inherent capabilities of the system. Although it is difficult to state dogmatically which scanning technique is best for each patient and condition, one or other technique is clearly preferable in some areas of medicine. Ultrasound, for example, should be used in obstetrics, while computerized tomography has revolutionised neuroradiological diagnosis. Nevertheless, there is still no substitute for good history taking and a thorough physical examination. The most important factor determining the choice of technique is the system's ability to answer the specific question required for the management of the patient.