Joaquim Gabriel

Ultrasonographic, thermographic and histologic evaluation of MNU-induced mammary tumors in female Sprague-Dawley rats

BACKGROUND As the worldwide breast cancer burden increases, non-invasive tools, such as ultrasonography and thermography are being increasingly sought after. N-methyl-N-nitrosourea-induced rat mammary tumors are important tools to investigate the usefulness of such imaging techniques. OBJECTIVE This study aimed to integrate both ultrasonographic and thermographic approaches to the vascularization and the superficial temperature of chemically-induced rat mammary tumors. MATERIALS AND METHODS Twenty-five female Sprague-Dawley rats were divided into two groups: group I (intraperitoneally administered with N-methyl-N-nitrosourea) and group II (control group). Thirty-five weeks after the administration of the carcinogen, mammary tumors were evaluated using Power Doppler, B Flow and Contrast-enhanced ultrasound, thermography and histology analyses. RESULTS Group I animals showed an average of 2.5 mammary tumors per animal, mostly papillary and cribriform non-invasive carcinomas. B Flow detected higher counts of colour pixels than Power Doppler. Contrast-enhanced ultrasound analysis showed a centripetal enhancement order of contrast agent and clear margins. Maximum tumor temperature and thermal amplitude determined by thermography were significantly correlated with tumor volume and with color pixel density, determined by Power Doppler. CONCLUSION B Flow was more sensitive than Power Doppler in detecting tumor vessels, but Power Doppler correlates with thermographic data concerning superficial temperature and may reflect tumor angiogenesis.

Dynamic monitoring of railway track displacement using an optical system

With the increases in traffic, axle loads and travelling speed, the dynamic monitoring of railway tracks and structures is becoming more and more important to ensure a high level of safety and comfort. This situation is particularly critical at transition zones where rapid changes of track stiffness occur. This paper presents a contactless system to measure track displacements and its application in an embankment/underpass transition zone, located on the Northern line of the Portuguese railway network where the Alfa Pendular tilting train travels at a maximum speed of 220 km/h. The system is based on a diode laser module and a position sensitive detector (PSD). The PSD receives the laser beam emission and the detection of the centre of gravity of the beam spotlight on the PSD area enables the calculation of the displacement. Before field application, static and dynamic laboratory validation tests were performed in order to evaluate the system performance for different laser to PSD distances, and an accuracy of 0.01 mm was achieved using data acquisition rates of up to 15 kHz. The optical measuring system proved to be an efficient and flexible way to measure absolute and relative rail displacements in the field, enabling the detection of track deformability differences along the transition zone, even for the passage of trains at high speed (220 km/h).

Long-term exercise training as a modulator of mammary cancer vascularization

BACKGROUND Breast cancer remains a leading cause of death by cancer worldwide. It is commonly accepted that angiogenesis and the expression of angiogenic factors such as vascular endothelial growth factor-A (VEGF-A) is associated with the increased risk of metastasis and poor patient outcome. OBJECTIVE This work aimed to evaluate the effects of long-term exercise training on the growth and vascularization of mammary tumors in a rat model. MATERIALS AND METHODS Fifty female Sprague-Dawley rats were divided into four groups: two N-methyl-N-nitrosourea (MNU)-exposed groups (exercised and sedentary) and two control groups (exercised and sedentary). MNU was administered once, intraperitoneally at 7 weeks-old. Animals were then exercised on a treadmill for 35 weeks. Mammary tumors were evaluated using thermography, ultrasonography [Power Doppler (PDI), B Flow and contrast-enhanced ultrasound (CEUS)], and immunohistochemistry (VEGF-A). RESULTS Both, MNU sedentary and exercised groups showed 100% of tumor incidence, but exercised animals showed less tumors with an increased latency period. Exercise training also enhanced VEGF-A immunoexpression and vascularization (microvessel density, MVD) (p<0.05), and reduced histological aggressiveness. Ultrasound and thermal imaging analysis confirmed the enhanced vascularization of tumors on exercised animals. CONCLUSION Long-term exercise training increased VEGF-A expression, leading to enhanced tumor vascularization and reduced tumor burden, multiplicity and histological aggressiveness.

Qigong as a Traditional Vegetative Biofeedback Therapy: Long-Term Conditioning of Physiological Mind-Body Effects

A contemporary understanding of Chinese Medicine (CM) regards CM diagnosis as a functional vegetative state that may be treated by vegetative reflex therapies such as acupuncture. Within this context, traditional mind-body exercises such as Qigong can be understood as an attempt to enhance physiological proprioception, by combining a special state of “awareness” with posture, movement, and breath control. We have formerly trained young auditing flutists in “White Ball” Qigong to minimize anxiety-induced cold hands and lower anxiety-induced heart rate. Functional changes occurred 2–5 min after training and were observed over the whole training program, allowing the children to control their symptoms. In our current work, we report that warm fingers and calm hearts could be induced by the children even without Qigong exercises. Thus, these positive changes once induced and “conditioned” vegetatively were stable after weeks of training. This may show the mechanism by which Qigong acts as a therapeutic measure in disease: positive vegetative pathways may be activated instead of dysfunctional functional patterns. The positive vegetative patterns then may be available in critical stressful situations. Qigong exercise programs may therefore be understood as an ancient vegetative biofeedback exercise inducing positive vegetative functions which are added to the individual reactive repertoire.

An agent methodology for processes, the environment, and services

Implementing and deploying a complete multi-agent system in whatever domain, especially those that are inherently complex and dynamic, is undoubtedly a very hard and time-consuming task. This paper analyzes the adequacy of traditional approaches in the field of Agent-Oriented Software Engineering to create adequate multi-agent systems applicable to the transportation domain. Our findings suggested that, albeit some approaches are intended to be generic enough to represent a wide range of different domains, intelligent transportation systems and more specifically the whole complexity of future urban transport are not totally supported. We propose a novel methodology where the concept of services is considered as peer of agents, ambient and processes. Also services rise as prominent elements in the modeling phase. The approach, illustrated as a typical scenario in the transport domain, is instantiated, which serves to clarify the whole process and main concepts in our modeling methodology.

Highly focalised thermotherapy using a ferrimagnetic cement in the treatment of a melanoma mouse model by low temperature hyperthermia

Purpose: Evaluation of the effectiveness of highly focalised thermotherapy (HFT) in a melanoma mouse model, using a ferrimagnetic cement (FC) and repeated low hyperthermia treatments. Materials and methods: A melanoma mouse model was induced with B16F10 cells in C57BL6 mice. The FC, injected into the tumour, was used as the magnetic vehicle for HFT. FC location within the tumour was assessed by radiography and its capability to generate heat, when exposed to an external high frequency magnetic field (HFMF), monitored by thermal camera. The HFT treatment consisted of three HFMF exposures, with 48-h intervals, each one lasting 30 min, with a 5–6°C tumour temperature increase. At the end of the experiment, FC samples were characterised by scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS). The presence of iron contents was analysed in the tumour, lungs, liver and spleen. Histological evaluation and immunohistochemical staining for caspase-3 were performed. Tumour growth was monitored during the experiment. Results: Surface analysis showed FC stabilisation within the tumour, and iron was absent. The thermal camera confirmed the localised temperature increase in the tumour. HFT treatments inhibited the tumour growth by ∼70% compared to controls. This was due to cell destruction by necrosis and apoptosis. Conclusions: The HFT, using the FC, proved to be a minimally invasive technique that statistically inhibited tumour growth. Results suggested that this methodology seems to be a promising technique for the treatment of solid tumours, allowing repeated low hyperthermia treatments, which can be easier and less traumatic than other hyperthermia techniques.

Hands-on using on-line engineering: The trend to better solutions

The use of on-line experiments has been offering new resources and opportunities for laboratory training activities, especially in many engineering areas.

Application of Infrared Thermal Imaging in a Violinist with Temporomandibular Disorder.

Temporomandibular disorders (TMD) consist of a group of pathologies that affect the masticatory muscles, temporomandibular joints (TMJ), and/or related structures. String instrumentalists, like many orchestra musicians, can spend hours with head postures that may influence the biomechanical behavior of the TMJ and the muscles of the craniocervicomandibular complex (CCMC). The adoption of abnormal postures acquired during performance by musicians can lead to muscular hyperactivity of the head and cervical muscles, with the possible appearance of TMD. Medical infrared thermography is a non-invasive procedure that can monitor the changes in the superficial tissue related to blood circulation and may serve as a complement to the clinical examination. The objective of this study was to use infrared thermography to evaluate, in one subject, the cutaneous thermal changes adjacent to the CCMC that occur before, during, and after playing a string instrument.

A platform for the design, simulation and development of quadcopter multi-agent systems

Unmanned Aerial Vehicles (UAVs) are gaining the attention of researchers around the world. Recently researchers apply the multi-agent paradigm to such domain taking advantage of its research in cognition, deliberation, and mainly coordination mechanisms. The aim of our research is to contribute to the multiple quadcopter simulation area introducing a platform for the design, simulation, and development of quadcopter MultiAgent Systems (MAS). Specifically for this paper, we minutely discuss the proposed architecture and present the implemented prototype focusing our experiments on the scalability and the resource usage of it. The results demonstrate that the centralised perspective limits the scalability mainly when the physical engine is being used; also, we identify that the method responsible for the 3D update is the platforms bottleneck. After this work different type of studies in social interaction of quadcopters will follow up as well as the improvement of the proposed architecture, for instance, using a multi-threading approach.

Sensing Bluetooth Mobility Data: Potentials and Applications

Information related to mobility dynamics constitutes an important factor to be considered in traffic management to improve the efficiency of existing systems. We present a proof-of-concept deployment of sensors using the Bluetooth technology to detect traffic flow conditions. Besides traditional method consisting of a network of stationary sensors, we present a novel approach that uses sensors deployed in moving vehicles that allows new type studies and captures new insights of mobility. Both approaches complement the most common methods of traffic sensing while being more cost-effective and easily available. Early experimental results show the variety of information available through both approaches spanning from Origin/Destination matrices and travel times to insights into emerging mobile neighborhoods. These metrics are important to improve traffic management increasing the efficiency of urban mobility networks.