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Networks of random-assembled gold clusters produced in the gas phase show resistive switching (RS) activity at room temperature and they are suitable for the fabrication of devices for neuromorphic data processing and classification. Fully connected cluster-assembled nanostructured Au films are characterized by a granular structure rich of interfaces, grain boundaries and crystalline defects. Here we report a systematic characterization of the electroforming process of the cluster-assembled films demonstrating how this process affects the interplay between the nano- and mesoscale film structure and the neuromorphic characteristics of the resistive switching activity. The understanding and the control of the influence of the resistive switching forming process on the organization of specific structures at different scales of the cluster-assembled films, provide the possibility to engineer random-assembled neuromorphic architectures for data processing task.
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Since infrared reflectography was first applied in the 1960s to visualize the underdrawings of ancient paintings, several devices and scanning techniques were successfully proposed both as prototypes and commercial instruments. In fact, because of the sensors' small dimension, typically ranging from 0.1 to 0.3 megapixels, scanning is always required. Point, line, and image scanners are all viable options to obtain an infrared image of the painting with adequate spatial resolution. This paper presents a newly developed, tailormade scanning system based on an InGaAs camera equipped with a catadioptric long-focus lens in a fixed position, enabling all movements to occur by means of a rotating mirror and precision step motors. Given the specific design of this system, as the mirror rotates, refocus of the lens is necessary and it is made possible by an autofocus system involving a laser distance meter and a motorized lens. The system proved to be lightweight, low cost, easily portable, and suitable for the examination of large-scale painting surfaces by providing high-resolution reflectograms. Furthermore, high-resolution images at different wavelengths can be obtained using band-pass filters. The in-situ analysis of a 16th-century panel painting is also discussed as a representative case study to demonstrate the effectiveness and reliability of the system described herein.
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In the present work, a complete non-invasive scientific investigation of six Utagawa Kunisada's woodblock prints (nishiki-e) belonging to the Oriental Art Museum "E. Chiossone" (Genoa, Italy), was performed in situ. The campaign started with high resolution multiband imaging (visible, multiband fluorescence, near infrared) followed by reflectance transformation imaging (RTI) to characterize and highlight the peculiar printing techniques and the condition of the support. Then fiber optics reflectance spectroscopy (FORS), spectrofluorimetry, Raman and reflectance Fourier-transform infrared (FTIR) spectroscopies were successfully applied in synergy for the investigation of the printing materials (pigments, binders, support). The results obtained represent a set of very important information for these never-before-studied works of art, useful to the different professionals involved: historians, conservators and curators. The materials identified were completely in agreement with those traditionally used in the Edo period in the 19th century, while the computational imaging technique RTI gave an additional amount of information in terms of surface characterization that could not be overlooked when studying these works of art. RTI data were further processed to enhance the texture visualization.
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Tecnologia de Fibra Óptica , Museus , Japão , Espectroscopia de Infravermelho com Transformada de Fourier , Tecnologia de Fibra Óptica/métodos , ItáliaRESUMO
Reflectographic analyses applied on paintings can be performed using cameras equipped with different detectors with different abilities in detecting and visualizing underdrawings, repainting, restorations, and other nonvisible information. In this research, the results obtained through thermographic imaging followed by statistical imaging postprocessing methods have been compared with those obtained with traditional reflectographic methods in the short-wave infrared range. The comparison has been performed studying the thermal sequence after a single pulse of light with a different spectrum of ad hoc mock-ups. Results showed that for limited cases, signal-to-noise ratio seems to be more relevant in obtaining reliable images of underdrawings with respect to the effect of optical absorption of visible light by painting layers.
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In healthy subjects, the transient perturbation of body part ownership is accompanied by regional skin temperature decrease. This observation leaves an open question about a possible body part-specific thermoregulatory response in pathological conditions, in which the sense of ownership over that body part is altered. For instance, Body Integrity Dysphoria (BID), a poorly understood neuropsychiatric disorder, is characterised by the non-acceptance of one or more of one's extremities. This unsettling feeling pervasively captures the individuals' attention towards the unwanted limb. Previous studies characterised BID in terms of absent ownership feeling with preserved ownership judgment. We explored for the first time whether this altered feeling is also associated with a specific thermoregulatory response. We recorded thermal image sequences of circumscribed regions of the limbs' skin in seven individuals with BID desiring to remove one leg while they were invited to focus their attention toward one particular limb (arm or leg). Their event-related thermoregulatory pattern was compared to a group of healthy matched controls. In individuals with BID but not in control persons, we found a bilateral decrease in leg temperature when focusing their attention on either the unwanted or accepted leg. The event-related thermoregulatory response for both upper limbs was similar between individuals with BID and healthy controls. Our results suggest that the alteration of the sense of body ownership in neuropsychiatric conditions such as BID may critically rest on specific event-related thermoregulatory patterns in response to modulation of attention to body parts.
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Imagem Corporal , Corpo Humano , Imagem Corporal/psicologia , Humanos , PropriedadeRESUMO
BACKGROUND: Animal models used to study pathologies requiring rehabilitation therapy, such as cardiovascular and neurologic disorders or oncologic disease, must be as refined and translationally relevant as possible. Sometimes, however, experimental procedures such as those involving restraint may generate undesired effects which may act as a source of bias. However, the extent to which potentially confounding effects derive from such routine procedures is currently unknown. Our study was therefore aimed at exploring possible undesirable effects of acute restraint stress, whereby animals were exposed to a brightly lit enclosed chamber (R&L) similar to those that are commonly used for substance injection. We hypothesised that this would induce a range of unwanted physiological alterations [such as neuroinflammatory response and changes in body weight and in brown adipose tissue (BAT)] and behavioural modification, and that these might be mitigated via the use of non-aversive handling methods: Tunnel Handling (NAH-T) and Mechanoceptive Handling (NAH-M)) as compared to standard Tail Handling (TH). METHODS: Two indicators of physiological alterations and three potentially stress sensitive behavioural parameters were assessed. Physiological alterations were recorded via body weight changes and assessing the temperature of Brown Adipose Tissue (BAT) using infra-red thermography (IRT), and at the end of the experiment we determined the concentration of cytokines CXCL12 and CCL2 in bone marrow (BM) and activated microglia in the brain. Nest complexity scoring, automated home-cage behaviour analysis (HCS) and Elevated Plus Maze testing (EPM) were used to detect any behavioural alterations. Recordings were made before and after a 15-minute period of R&L in groups of mice handled via TH, NAH-T or NAH-M. RESULTS: BAT temperature significantly decreased in all handling groups following R&L regardless of handling method. There was a difference, at the limit of significance (p = 0.06), in CXCL12 BM content among groups. CXCL12 content in BM of NAH-T animals was similar to that found in Sentinels, the less stressed group of animals. After R&L, mice undergoing NAH-T and NAH-M showed improved body-weight maintenance compared to those exposed to TH. Mice handled via NAH-M spent a significantly longer time on the open arms of the EPM. The HCS results showed that in all mice, regardless of handling method, R&L resulted in a significant reduction in walking and rearing, but not in total distance travelled. All mice also groomed more. No difference among the groups was found in Nest Score, in CCL2 BM content or in brain activated microglia. CONCLUSIONS: Stress induced by a common restraint procedure caused metabolic and behavioural changes that might increase the risk of unexpected bias. In particular, the significant decrease in BAT temperature could affect the important metabolic pathways controlled by this tissue. R&L lowered the normal frequency of walking and rearing, increased grooming and probably carried a risk of low-grade neuro-inflammation. Some of the observed alterations can be mitigated by Non-aversive handlings.
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Tecido Adiposo Marrom/metabolismo , Quimiocina CCL2/metabolismo , Quimiocina CXCL12/metabolismo , Doenças Neuroinflamatórias/psicologia , Animais , Temperatura Corporal , Peso Corporal , Modelos Animais de Doenças , Manobra Psicológica , Masculino , Camundongos , Doenças Neuroinflamatórias/etiologia , Doenças Neuroinflamatórias/imunologia , Restrição FísicaRESUMO
Pulsed thermography was exploited to identify the presence of glass defects in order to get an indication of the conservation status of archaeological glass. Indeed, the process of degradation in artifacts subjected to centuries of burial can be of great relevance. More specifically, we evaluated the potential of pulsed thermography to map the presence of flakes in archaeological glass. This was achieved by comparing different heating setups and signal-processing algorithms. Tests were carried out previously on glass mockups with surface defects and then on archaeological artifacts.
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The principles of Refinement, Replacement and Reduction (3R's) should be taken into account when animals must be used for scientific purpose. Here, a Reduction / Refinement approach was applied to the procedure of spinal cord injury (SCI), an animal model used in rehabilitation medicine research, in order to improve the quality of experiments, avoiding unnecessary suffering. The aims of this investigation were 1- to assess acute surgical pain in mice subjected to SCI, 2- to compare the efficacy of commonly used analgesia (three buprenorphine subcutaneous injection in 48 hours, 0,15 mg/kg each) with a combination of opioid and NSAID (one subcutaneous injection of 5 mg/kg carprofen before surgery followed by three buprenorphine subcutaneous injection in 48 hours, 0,15 mg/kg each) and 3- to test if Infrared Thermography (IRT) could be a potential new Refinement method to easily assess thermoregulation, an important metabolic parameter. Finally, we aimed to achieve these goals without recruiting animals on purpose, but using mice already scheduled for studies on SCI. By using behaviours analysis, we found that, despite being commonly used, buprenorphine does not completely relieve acute surgical pain, whereas the combination of buprenorphine and carprofen significantly decreases pain signs by 80%. IRT technology turned out to be a very useful Refinement tool being a non invasive methods to measure animal temperature, particularly useful when rectal probe cannot be used, as in the case of SCI. We could find that temperatures constantly and significantly increased until 7 days after surgery and then slowly decreased and, finally, we could observe that in the buprenorphine and carprofen treated group, temperatures were statistically lower than in the buprenorphine-alone treated mice. To our knowledge this is the first work providing an analgesic Refinement and a description of thermoregulatory response using the IRT technology, in mice subjected to SCI.
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Analgésicos/uso terapêutico , Modelos Animais de Doenças , Pesquisa de Reabilitação , Traumatismos da Medula Espinal/reabilitação , Termografia , Analgésicos Opioides/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Buprenorfina/uso terapêutico , Carbazóis/uso terapêutico , Raios Infravermelhos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Medição da Dor , Dor Pós-Operatória/tratamento farmacológicoRESUMO
Although moderate relationships (|r| â¼ 0.5) were reported between skin temperature and performance-related variables (e.g., kinetic), it remains unclear whether skin temperature asymmetry reflects muscle force imbalance in cycling. Therefore, the aim of this study was to assess whether a relationship exists between kinetic and thermal asymmetry during a fatiguing exercise. Ten elite cyclists were enrolled and tested on a maximal incremental cycling test. Peak crank torques of both legs were obtained at the initial and final workload. Likewise, bilateral skin temperatures were recorded before and after exercise. Asymmetric indexes were also calculated for kinetic (AIK) and skin temperature (AIT) outcomes. The bilateral peak crank torques showed a larger difference at the final compared to the initial workload (p < 0.05) of the incremental exercise. Conversely, the bilateral skin temperature did not show any differences at both initial and final workload (p > 0.05). Additionally, trivial relationships were reported between AIK and AIT (-0.3 < r < 0.2) at the initial and final workload. The obtained results showed that changes in bilateral kinetic values did not reflect concurrent changes in bilateral skin temperatures. This finding emphasizes the difficulty of associating the asymmetry of skin temperature with those of muscle effort in elite cyclists. Lastly, our study also provided further insights on thermal skin responses during exhaustive cycling exercise in very highly-trained athletes.
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Facial asymmetry is considered a marker of psychological, emotional and physiological distress, while anxiety is a behavioural, psychological and physiological response to a threat to well-being. Since individuals respond to anxiety with specific patterns (e.g., muscular tension), it is reasonable to hypothesize that anxiety could contribute to facial tension and therefore facial asymmetry. Instead, since facial asymmetry is perceived as "unpleasant" from peers, its presence may be a hindrance to social adaptation contributing to generate anxiety. In this study, we investigated whether resting facial asymmetry and anxiety are associated in young population. Full frontal facial photographs of 56 Caucasian males were taken in resting state to obtain indices of asymmetry in six facial landmarks. Anxiety status was assessed using the State-Trait Anxiety Inventory (STAI-Y). Analysis of the face showed that asymmetry and laterality of specific facial landmarks were associated with anxiety. State anxiety was associated with eyebrow and lateral angle of the eye, while trait anxiety was associated with eyebrow and lateral angle of the mouth. Moreover, as compared with contralateral landmarks, the left landmarks were lifted/expanded in subjects with elevated trait/state anxiety, whereas the right landmarks were lifted/expanded in subjects with low-trait/state anxiety.
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Ansiedade , Assimetria Facial , Ansiedade/fisiopatologia , Lateralidade Funcional , Humanos , Masculino , Personalidade/fisiologia , Escalas de Graduação Psiquiátrica , Descanso , População Branca , Adulto JovemRESUMO
PURPOSE: To determine the efficacy of an anti-discoloration system (ADS) in a 0.12% chlorhexidine (CHX) mouthwash to reduce dental discoloration. METHODS: A triple-blind, cross-over, randomized clinical trial was carried out in 22 healthy volunteers asked to perform oral rinses, twice a day for 21 days, using 0.12% CHX mouthwashes containing or not ADS (wash-out= 21 days). Dental discolorations were compared via spectroscopy (ΔE), and direct visual examination performed by the dentist and volunteers themselves. At 6 months, a further visual analysis on clinical images was carried out by the same volunteers and ad hoc recruited dental practitioners. RESULTS: A slight discoloration was the most frequent finding, independent of the presence of ADS, while the few severe cases of staining were associated with CHX alone. (ΔE values comparing dental color before and after treatments were similar for CHX (8.4±0.1) and CHX+ADS (8.6±0.9) rinses. Direct visual analysis showed no staining difference between the two mouthwashes. Six months later, volunteers' self-evaluation of clinical pictures again did not detect any significant difference between treatments, while dental practitioners identified CHX+ADS as less discoloring (< 0.05). Slight dental discoloration represents the most common side-effect of 0.12% CHX mouthwash, independent of the presence of ADS. Severe cases are possible, but very rare and mainly associated with CHX alone. CLINICAL SIGNIFICANCE: There was no evidence to support the 0.12% chlorhexidine with anti-discoloration agent to reduce staining.
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Clorexidina/uso terapêutico , Antissépticos Bucais/uso terapêutico , Descoloração de Dente/tratamento farmacológico , Anti-Infecciosos Locais , Placa Dentária , Humanos , DenteRESUMO
Non-invasive, portable analytical techniques are becoming increasingly widespread for the study and conservation in the field of cultural heritage, proving that a good data handling, supported by a deep knowledge of the techniques themselves, and the right synergy can give surprisingly substantial results when using portable but reliable instrumentation. In this work, pigment characterization was carried out on 21 Leonardesque paintings applying in situ X-ray fluorescence (XRF) and fiber optic reflection spectroscopy (FORS) analyses. In-depth data evaluation allowed to get information on the color palette and the painting technique of the different artists and workshops . Particular attention was paid to green pigments (for which a deeper study of possible pigments and alterations was performed with FORS analyses), flesh tones (for which a comparison with available data from cross-sections was made), and ground preparation.
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PURPOSE: To assess the impact of implant system on color harmonization of periimplant mucosa. MATERIALS AND METHODS: In this case series, color of periimplant mucosa was compared with color of natural tooth gingiva. Seventeen intercanine implants were analyzed (11 bone level [BL], 6 tissue level [TL] implants). Colorimetric data, at 2, 4, and 6 mm from gingival margin, were collected through fiber optics reflectance spectroscopy, and color differences calculated as ΔE. Dentists, dental students, and lay people, in blind, performed an additional visual color analysis on clinical images. RESULTS: Independently from implant system, the color of periimplant mucosa was significantly different from gingiva (ΔE = 8.2 ± 0.7), resulting darker at L* comparison (P ≤ 0.05). TL periimplant mucosa showed higher ΔE than BL (9.0 ± 1.0 vs 6.6 ± 0.8, respectively; P ≤ 0.05). Observers correctly identified where the implant was placed in about half of the cases, with no significant difference between implant systems. CONCLUSION: Within the limitations of this study, the color of periimplant soft tissues appears different from gingiva, at spectroscopic analysis. Color discrepancy results higher in the presence of TL implants than in BL implants, although the difference may not be clinically significant.
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Implantes Dentários , Gengiva/patologia , Mucosa Bucal/patologia , Idoso , Idoso de 80 Anos ou mais , Cor , Feminino , Tecnologia de Fibra Óptica , Humanos , Masculino , Pessoa de Meia-Idade , Fotografia Dentária , Estudos Retrospectivos , Análise EspectralRESUMO
The use of thermal imaging in monitoring the dynamic of skin temperature during prolonged physical exercise is central to assess athletes' ability to dissipate heat from the skin surface to the environment. In this study, seven elite cyclists completed an incremental maximal cycling test to evaluate their skin temperature response under controlled-environment conditions. Thermal images have been analyzed using a method based on maxima detection (Tmax). Data confirmed a reduction in skin temperature due to vasoconstriction during the exercise, followed by a temperature increment after exhaustion. A characteristic hot-spotted thermal pattern was found over the skin surface in all subjects. This research confirmed also the notable ability by highly trained cyclists to modify skin temperature during an incremental muscular effort. This study gives additional contributions for understanding the capability of the Tmax method applied to the thermoregulatory physiological processes.
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Ciclismo/fisiologia , Temperatura Cutânea , Termografia/métodos , Adulto , Exercício Físico , Humanos , MasculinoRESUMO
Low intensity resistance training with slow movement and tonic force generation has been shown to create blood flow restriction within muscles that may affect thermoregulation through the skin. We aimed to investigate the influence of two speeds of exercise execution on skin temperature dynamics using infrared thermography. Thirteen active males performed randomly two sessions of squat exercise (normal speed, 1s eccentric/1s concentric phase, 1s; slow speed, 5s eccentric/5s concentric phase, 5s), using ~50% of 1 maximal repetition. Thermal images of ST above muscles quadriceps were recorded at a rate of 0.05Hz before the exercise (to determine basal ST) and for 480s following the initiation of the exercise (to determine the nonsteady-state time course of ST). Results showed that ST changed more slowly during the 5s exercise (p=0.002), whereas the delta (with respect to basal) excursions were similar for the two exercises (p>0.05). In summary, our data provided a detailed nonsteady-state portrait of ST changes following squat exercises executed at two different speeds. These results lay the basis for further investigations entailing the joint use of infrared thermography and Doppler flowmetry to study the events taking place both at the skin and the muscle level during exercises executed at slow speed.
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Regulação da Temperatura Corporal , Exercício Físico , Fluxo Sanguíneo Regional , Treinamento Resistido/métodos , Temperatura Cutânea , Pele/irrigação sanguínea , Adulto , Humanos , Masculino , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/fisiologia , Termografia , Adulto JovemRESUMO
PURPOSE: To evaluate the application of a fiber optic reflectance spectroscopy (FORS) prototype probe for 45°x: 45° FORS for determining color of dental materials. A portable spectrophotometer with a highly manageable fiber optics co-axial probe was used to apply 45°x: 45° FORS for color matching in restorative dentistry. METHODS: The color coordinates in CIELAB space of two dental shade guides and of the corresponding photopolymerized composites were collected and compared. The 45°x: 45° FORS with the co-axial probe (test system), the integrating sphere spectroscopy (reference system) and a commercial dental colorimeter (comparator system) were used to collect data and calculate color differences (ΔE and ΔE00). RESULTS: FORS system displayed high repeatability, reproducibility and accuracy. ΔE and ΔE00 values between the shade-guide, each other, and the corresponding composites resulted above the clinically acceptable limit. The 45°x: 45° FORS test system demonstrated suitable in vitro performance for dental composite color evaluation. CLINICAL SIGNIFICANCE: 45°x: 45° fiber optic reflectance spectroscopy allows reliable color analysis of small surfaces of dental composites, favoring the color matching of material with the closely surrounding dental tissue, and confirming significant color differences between shade guide tabs and photo-polymerized composites.
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Cor , Colorimetria/métodos , Resinas Compostas/química , Materiais Dentários/química , Tecnologia de Fibra Óptica , Análise Espectral/métodos , Polimerização , Reprodutibilidade dos Testes , Propriedades de SuperfícieRESUMO
INTRODUCTION: The authors describe the thermography technique in animal production and in veterinary medicine applications. The thermographic technique lends itself to countless applications in biology, thanks to its characteristics of versatility, lack of invasiveness and high sensitivity. Probably the major limitation to most important aspects for its application in the animal lies in the ease of use and in its extreme sensitivity. MATERIALS AND METHODS: This review provides an overview of the possible applications of the technique of thermo visual inspection, but it is clear that every phenomenon connected to temperature variations can be identified with this technique. Then the operator has to identify the best experimental context to obtain as much information as possible, concerning the physiopathological problems considered. Furthermore, we reported an experimental study about the thermography (IRT) as a noninvasive technique to assess the state of wellbeing in working dogs. RESULTS: The first results showed the relationship between superficial temperatures and scores obtained by the animal during the behavioral test. This result suggests an interesting application of infrared thermography (IRT) to measure the state of wellbeing of animals in a noninvasive way.
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Bem-Estar do Animal , Cães/fisiologia , Termografia/métodos , Medicina Veterinária/instrumentação , Animais , CoelhosRESUMO
Heat dissipation during sport exercise is an important physiological mechanism that may influence athletic performance. Our aim was to test the hypothesis that differences exist in the dynamics of exercise-associated skin temperature changes between trained and untrained subjects. We investigated thermoregulation of a local muscle area (muscle-tendon unit) involved in a localized steady-load exercise (standing heels raise) using infrared thermography. Seven trained female subjects and seven untrained female controls were studied. Each subject performed standing heels raise exercise for 2 min. Thermal images were recorded prior to exercise (1 min), during exercise (2 min), and after exercise (7 min). The analysis of thermal images provided the skin temperature time course, which was characterized by a set of descriptive parameters. Two-way ANOVA for repeated measures detected a significant interaction (p = 0.03) between group and time, thus indicating that athletic subjects increased their skin temperature differently with respect to untrained subjects. This was confirmed by comparing the parameters describing the speed of rise of skin temperature. It was found that trained subjects responded to exercise more quickly than untrained controls (p < 0.05). In conclusion, physical training improves the ability to rapidly elevate skin temperature in response to a localized exercise in female subjects.
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Exercício Físico/fisiologia , Temperatura Cutânea/fisiologia , Adolescente , Atletas , Engenharia Biomédica , Regulação da Temperatura Corporal/fisiologia , Feminino , Humanos , Natação/fisiologia , Termografia , Adulto JovemRESUMO
Specific respiratory muscle training improves athletes' performance particularly at high intensities. This work aims to study the usability of infrared thermography to evaluate two types of breathing, thoracic and diaphragmatic, on the cartographies of the cutaneous temperature of the trunk. IR thermography is a non-invasive technique that visually represents the whole process during and after training. A well trained subject in both respirations performed the exercise with SpiroTiger® for 5 minutes, followed by 5 minutes of recovery. Ten Regions of Interest on the subject skin were selected following anatomical and functional correspondence with the muscles involved in breathing. In order to check functional behaviour of respiratory muscles, we calculated the correlation among thermal data of all the ROI. Global temperature of body trunk showed a general decrease of few degrees during both kinds of the training but thermal imaging documented also thermal spots of increasing temperature in pectoral areas due to the superficial vasocirculation in thoracic breathing. The results indicate that thermal imaging can be used for quantitative evaluation of the cutaneous temperature in various trunk zones characterized by thoracic and diaphragmatic breathing. This work can be considered a preliminary study to the development of future statistical study.