Short-Term Thermal Effect of Continuous Ultrasound from 3 MHz to 1 and 0.5 W/cm2 Applied to Gastrocnemius Muscle.

Continuous ultrasound is recognized for its thermal effect and use in the tissue repair process. However, there is controversy about its dosage and efficacy. This study used infrared thermography, a non-invasive technique, to measure the short-term thermal effect of 3 MHz continuous ultrasound vs. a placebo, referencing the intensity applied. It was a single-blind, randomized clinical trial of 60 healthy volunteers (19-24 years old) divided into three equal groups. Group 1:1 W/cm2 for 5 min; Group 2: 0.5 W/cm2 for 10 min; and Group 3: the placebo for 5 min. The temperature was recorded through five thermographic images per patient: pre- and post-application, 5, 10, and 15 min later. After statistical analysis, a more significant decrease in temperature (p<0.05 ) was observed in the placebo group compared with the remaining groups after the application of continuous ultrasound. Group 1 was the one that generated the highest significant thermal effect (p<0.001), with an increase of 3.05 °C at 15 min, compared with the other two groups. It is concluded that to generate a thermal effect in the muscle, intensities of ≥1 W/cm2 are required, since the dosage maintained a temperature increase for more than 5 min.

Knee skin temperature response of patients with bilateral patellofemoral syndrome before and after heat and cold stress.

Patellofemoral Pain Syndrome is characterized by the presence of pain in the front area of the knee, which occurs when performing common activities such as climbing stairs, and bending the knees, among others. The objective of this research was to evaluate the detection capability of infrared thermography in patients with Patellofemoral Pain Syndrome, in the baseline state, as well as after the application of thermal stress. The investigation was conducted in 48 patients, who were subdivided into four groups (n = 12). Two subgroups were healthy patients and two with Patellofemoral Pain Syndrome. For the diagnosis of the syndrome, a manual evaluation was performed using the Zohlen test and Q angle measurement. Subsequently, cold stress was applied for 10 min to a healthy subgroup and an experimental subgroup. The remaining two subgroups were subjected to heat stress for 15 min. Thermographic images of the lower extremities were acquired at seven time points, at baseline, immediately after application of thermal stress and then every 3 min until 15 min were completed. It was observed that patients presented Patellofemoral Pain Syndrome bilaterally. After statistical analysis, it was found that there were no significant differences in baseline temperature between the groups. However, for heat stress, a higher temperature was observed in the group with Patellofemoral Pain Syndrome (p < 0.05) in the recovery period, and in the case of cold stress, only a lower temperature in the left knee immediately after the application. In conclusion, it is not possible to detect patellofemoral syndrome bilaterally in the baseline state by thermography and neither is it evident in cold stress. However, after heat stress, thermal recovery is lower for the PFPS group, so it would be susceptible to detection.

Automatic Segmentation of Facial Regions of Interest and Stress Detection Using Machine Learning.

Stress is a factor that affects many people today and is responsible for many of the causes of poor quality of life. For this reason, it is necessary to be able to determine whether a person is stressed or not. Therefore, it is necessary to develop tools that are non-invasive, innocuous, and easy to use. This paper describes a methodology for classifying stress in humans by automatically detecting facial regions of interest in thermal images using machine learning during a short Trier Social Stress Test. Five regions of interest, namely the nose, right cheek, left cheek, forehead, and chin, are automatically detected. The temperature of each of these regions is then extracted and used as input to a classifier, specifically a Support Vector Machine, which outputs three states: baseline, stressed, and relaxed. The proposal was developed and tested on thermal images of 25 participants who were subjected to a stress-inducing protocol followed by relaxation techniques. After testing the developed methodology, an accuracy of 95.4% and an error rate of 4.5% were obtained. The methodology proposed in this study allows the automatic classification of a person's stress state based on a thermal image of the face. This represents an innovative tool applicable to specialists. Furthermore, due to its robustness, it is also suitable for online applications.

Face Thermal Map of the Mexican Population in the Basal State.

There has been a wide use of thermal images of the human body in recent years, specifically images with thermal information of regions of interest (ROI) in the face; this information can be used for epidemiological, clinical, and/or psychological purposes. Due to this, it is important to have plenty of information on temperature in these ROIs in the basal state that allows their use as a reference in terms of their thermal analysis. In this work, a face thermal map of the Mexican population in the basal state (n = 196) is created, adding the comparison between different population groups, such as gender, age, and clinical status, obtaining results of great interest for future research. The t-test for independent samples was applied to the ROIs with normal distribution and Mann−Whitney u-test to the ones that did not present normal distribution. Statistically significant differences were found in some of the ROI comparisons like the corrugator, the supraorbitals, and the chin between the control and clinical groups, as well as in the differentiation by age (p < 0.05).

Diagnostic Strategies for Breast Cancer Detection: From Image Generation to Classification Strategies Using Artificial Intelligence Algorithms.

Breast cancer is one the main death causes for women worldwide, as 16% of the diagnosed malignant lesions worldwide are its consequence. In this sense, it is of paramount importance to diagnose these lesions in the earliest stage possible, in order to have the highest chances of survival. While there are several works that present selected topics in this area, none of them present a complete panorama, that is, from the image generation to its interpretation. This work presents a comprehensive state-of-the-art review of the image generation and processing techniques to detect Breast Cancer, where potential candidates for the image generation and processing are presented and discussed. Novel methodologies should consider the adroit integration of artificial intelligence-concepts and the categorical data to generate modern alternatives that can have the accuracy, precision and reliability expected to mitigate the misclassifications.

Smart Sensor Based on Biofeedback to Measure Child Relaxation in Out-of-Home Care.

Children from out-of-home care are a vulnerable population that faces high stress and anxiety levels due to stressful experiences, such as being abused, being raped, and violence. This problem could have negative effects on their bio-psycho-social well-being if they are not provided with comprehensive psychological treatment. Numerous methods have been developed to help them relax, but there are no current approaches for assessing the relaxation level they reach. Based on this, a novel smart sensor that can evaluate the level of relaxation a child experiences is developed in this paper. It evaluates changes in thermal biomarkers (forehead, right and left cheek, chin, and maxillary) and heart rate (HR). Then, through a k-nearest neighbors (K-NN) intelligent classifier, four possible levels of relaxation can be obtained: no-relax, low-relax, relax, and very-relax. Additionally, an application (called i-CARE) for anxiety management, which is based on biofeedback diaphragmatic breathing, guided imagery, and video games, is evaluated. After testing the developed smart sensor, an 89.7% accuracy is obtained. The smart sensor used provides a reliable measurement of relaxation levels and the i-CARE application is effective for anxiety management, both of which are focused on children exposed to out-of-home care conditions.

Physiological stressor impact on peripheral facial temperature, Il-6 and mean arterial pressure, in young people.

Nowadays, stress is part of everyday life, whose long-term effects can trigger health risks. Among the main alterations that occur in the human body we can find the variation of inflammatory activity, blood pressure, and facial peripheral temperature. The objective of this work is to show the facial thermal behavior for men and women, as well as the differences in vascular and inflammatory responses induced by the effect of acute social stress. The Trier Social Stress Test was applied to 15 women and 15 men, free of disease, with an average age of 23.8 years and a standard deviation of 5.52. After capturing the baseline state, and at the end of the test, the inflammatory activity was measured through salivary interleukin-6; the mean blood pressure, and the capture of facial thermographic images. For the thermal images, six regions of interest (biothermomarkers) were analyzed: forehead, right cheek, left cheek, chin, nose, and corrugator muscle. The results obtained after analyzing the information were: an increase in inflammatory activity, an increase in mean blood pressure, and significant temperature changes in different areas of interest of the face, depending on gender. For men, it only appeared in the region of the nose and women's forehead, cheeks, and nose. Furthermore, the correlation between the three variables (il-6, blood pressure, and temperature) was performed and no significant values were found. Regarding the relationship between genders, only significant values were found for il-6.

Effects of the Trier Social Stress Test on the distributions of IL-6 and MAP levels.

Trier Social Stress Test (TSST) is an experimental psychological test that induces changes in autonomic, endocrinological and immunological activity. Two measures used to evaluate the inflammatory activity induced by this test are the interleukin 6 (IL-6), a cytokine sensitive to changes in sympathetic nervous activity, and the mean arterial pressure (MAP), a measure sensitive to changes in autonomic activity. This study had two goals: first, the study examined whether TSST increases IL-6 and MAP levels; second, pre- and post-TSST IL-6 levels were compared for participants whose IL-6 levels increased or decreased due to the TSST. Saliva samples of IL-6 and MAP were taken from 42 participants clinically healthy, without psychiatric history, and data were analysed via quantile comparisons. The results showed that TSST did not lead to an increase in sympathetic activity as indexed by IL-6. Instead, TSST led to increases in MAP. Also, there were significant differences between the IL-6 distributions of people whose IL-6 levels changed from low to high (63%) and from high to low (37%) before and after the TSST. These findings suggest that the TSST will not have the same effect on all participants; that is, individual differences can be assessed using a biomarker to identify people with specialized psychological care needs.