Finger Temperature Research Articles

Optimal iodine absorption line applied for spaceborne high spectral resolution lidar.

Spaceborne high spectral resolution lidar (HSRL) provides a wide range of observations, e.g., measurements of aerosol backscattering and extinction coefficients and aerosol depolarization ratio with high accuracy, which are of great significance to the study of air pollution monitoring and climate change. With different cells and finger temperatures, the transmittance of the different absorption lines of the iodine vapor filter at 532nm wavelength was measured. The 1064nm fundamental frequency pulse energy and the 532nm frequency-doubled pulse energy output of different seeder laser wavelengths were measured. Based on the relationship among the laser output power, the absorption line shape of the iodine vapor filter, and the atmospheric model, the echo power was calculated and compared. The 1110 iodine absorption line was selected as the optimized filter for the HSRL, which could increase in 22% and 14% efficiency compared with the traditional 1109 line, and a new proposed 1105 line at the 532nm HSRL channel at 5km altitude with an enhanced aerosol model, respectively.

The depersonalized brain: New evidence supporting a distinction between depersonalization and derealization from discrete patterns of autonomic suppression observed in a non-clinical sample.

Depersonalization and Derealization are characterised by feelings of detachment from one's bodily self/surroundings and a general emotional numbness. We explored predisposition to trait-based experiences of depersonalization/derealization-type experiences and autonomic arousal toward simulated body-threats, which were delivered to the participant's own body (i.e. Self) and when observed being delivered to another individual (i.e. Other). Ninety participants took part in an "Implied Body-Threat Illusion" task (Dewe, Watson, & Braithwaite, 2016) and autonomic arousal was recorded via standardised skin conductance responses and finger temperature. Autonomic suppression in response to threats delivered to the Self correlated with increases in trait-based depersonalization-type experiences. In contrast, autonomic suppression for threats delivered to Others correlated with trait-based derealization-like experiences. Body-temperature and anticipatory arousal did not correlate reliably with predisposition to depersonalization- or derealization-type experiences. The theoretical implications of these findings are discussed in terms of a fronto-limbic autonomic suppression mechanism.

L-Menthol attenuates the magnitude of cold-induced vasodilation on the extremities of young females

BackgroundMenthol chemically triggers cold-sensitive receptors in the skin without conductive skin cooling. We investigated the effects of menthol-induced activation of cutaneous cold receptors on the cold-induced vasodilation (CIVD) of the finger. We hypothesized that the menthol application would attenuate typical CIVD responses.Methods1.5% l-menthol was fully applied over the left hand and forearm, and then, the middle finger of the left hand was immersed into 4 °C water for 30 min. A trial consisted of 10-min rest followed by 30-min immersion and 20-min recovery in 28 °C air temperature with 20% relative humidity. Another trial without the menthol application was carried out as a control. Seventeen females (24.2 ± 2.6 years in age, 160.5 ± 5.1 cm in height, and 51.2 ± 5.7 kg in body weight) participated in the two trials.ResultsThe results showed that the maximum and average temperatures of the finger during the water immersion were lower in the menthol application when compared to control (P < 0.05), whereas no significant differences appeared in the onset time of CIVD, the frequency of CIVD, and minimum finger temperature. These results imply that stronger stimulation of cold receptors without additional conductive skin cooling did not attenuate the triggering of CIVD responses but intensified vasoconstriction after the first occurrence of CIVD.ConclusionIt is suggested that substantial and conductive heat loss through the skin along with activation of cold receptors may be required to retain rewarming at a certain level.

Localised Model-Based Active Controlling of Blood Flow During Chemotherapy to Prevent Nail Toxicity and Onycholysis

Chemotherapy-induced nail toxicity is a widely spread phenomenon. Cooling the patient’s hands can reduce blood flow to the fingers and consequently reducing the amount of chemical agents reaching the nails. This paper is aiming at developing a model-based controller of the finger’s skin temperatures and blood flow to reduce the risk of nail toxicity during chemotherapy. Experiments were conducted to model the dynamic response of the fingers skin temperature and blood flow using an ad hoc experimental device. The device was designed to provide a localised cooling of the fingers. The experiments were performed on a homogeneous test group of 11 middle-aged women. The fingers’ skin temperatures and blood flow were measured continuously. A second order discrete time transfer function model was suitable (R2 = 0.91 ± 0.18) in all the cases to model the dynamic responses of the fingers’ skin temperatures. The model estimation results have shown that the a- and b-parameters were varying among different test subjects and within the same subject. The resulted models were employed in designing a model-based proportional-integral-plus controller. Simulations of the closed-loop systems were performed based on the identified models for each test subject. The simulation results have shown that the designed controller is able to regulate the finger’s skin temperatures tightly about the desired level and yet, is still quite simple to implement in practice. Controlled active cooling with an online parameter estimation algorithm and continuous feedback of the patient finger temperatures is a promising solution to reduce nail toxicity during chemotherapy.

Effects of EVA glove on hand dexterity at low temperature and low pressure

Hand dexterity is an important index to assess whether extravehicular activity (EVA) gloves are appropriately designed. Pressurized gloves and low temperature environments can both cause a decrease in hand dexterity. However, due to the difficulty in performing tests under extreme conditions, there has been no report on dexterity tests with gloves under pressure and low temperature. To fill this gap, we performed a dexterity test of EVA gloves with twelve male volunteers involved under the extreme conditions, which were created in the low-pressure simulation cabin with vaporized liquid nitrogen used to cool it down. A total of nine conditions were designed. Purdue pegboard test and nut fastening test were improved before being applied in a hand dexterity test. Completion times for both tests, finger temperatures and cold feeling of the hand were recorded and analyzed. Results showed that the completion times for both tests increased either as the temperature decreased or as the pressure increased. Furthermore, a combined effect of low temperature and pressure was observed. The study provides evidence in support of astronaut training and optimization of EVA glove productivity.

Wireless Surface Electromyography and Skin Temperature Sensors for Biofeedback Treatment of Headache: Validation Study with Stationary Control Equipment

Background: The use of wearables and mobile phone apps in medicine is gaining attention. Biofeedback has the potential to exploit the recent advances in mobile health (mHealth) for the treatment of headaches. Objectives: The aim of this study was to assess the validity of selected wireless wearable health monitoring sensors (WHMS) for measuring surface electromyography (SEMG) and peripheral skin temperature in combination with a mobile phone app. This proof of concept will form the basis for developing innovative mHealth delivery of biofeedback treatment among young persons with primary headache. Methods: Sensors fulfilling the following predefined criteria were identified: wireless, small size, low weight, low cost, and simple to use. These sensors were connected to an app and used by 20 healthy volunteers. Validity was assessed through the agreement with simultaneous control measurements made with stationary neurophysiological equipment. The main variables were (1) trapezius muscle tension during different degrees of voluntary contraction and (2) voluntary increase in finger temperature. Data were statistically analyzed using Bland-Altman plots, intraclass correlation coefficient (ICC), and concordance correlation coefficient (CCC). Results: The app was programmed to receive data from the wireless sensors, process them, and feed them back to the user through a simple interface. Excellent agreement was found for the temperature sensor regarding increase in temperature (CCC .90; 95% CI 0.83-0.97). Excellent to fair agreement was found for the SEMG sensor. The ICC for the average of 3 repetitions during 4 different target levels ranged from .58 to .81. The wireless sensor showed consistency in muscle tension change during moderate muscle activity. Electrocardiography artifacts were avoided through right-sided use of the SEMG sensors. Participants evaluated the setup as usable and tolerable. Conclusions: This study confirmed the validity of wireless WHMS connected to a mobile phone for monitoring neurophysiological parameters of relevance for biofeedback therapy.

Music-Evoked Emotions—Current Studies

The present study is focused on a review of the current state of investigating music-evoked emotions experimentally, theoretically and with respect to their therapeutic potentials. After a concise historical overview and a schematic of the hearing mechanisms, experimental studies on music listeners and on music performers are discussed, starting with the presentation of characteristic musical stimuli and the basic features of tomographic imaging of emotional activation in the brain, such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), which offer high spatial resolution in the millimeter range. The progress in correlating activation imaging in the brain to the psychological understanding of music-evoked emotion is demonstrated and some prospects for future research are outlined. Research in psychoneuroendocrinology and molecular markers is reviewed in the context of music-evoked emotions and the results indicate that the research in this area should be intensified. An assessment of studies involving measuring techniques with high temporal resolution down to the 10 ms range, as, e.g., electroencephalography (EEG), event-related brain potentials (ERP), magnetoencephalography (MEG), skin conductance response (SCR), finger temperature, and goose bump development (piloerection) can yield information on the dynamics and kinetics of emotion. Genetic investigations reviewed suggest the heredity transmission of a predilection for music. Theoretical approaches to musical emotion are directed to a unified model for experimental neurological evidence and aesthetic judgment. Finally, the reports on musical therapy are briefly outlined. The study concludes with an outlook on emerging technologies and future research fields.

Evaluation on the effects of wax inhibitor and optimization of operating parameters for wax deposition in Malaysian crude oil

ABSTRACTThe complex phenomenon of wax deposition subject to thermal gradient in crude oil is one of the biggest challenges in petroleum industry. In this comparative study, two inhibitors which were poly(ethylene-co-vinyl acetate) (EVA) and xylene were investigated in terms of rate of wax deposition in Malaysian crude oil using one-factor-at-a-time (OFAT) approach and cold finger methods. Stirring rate and cold finger temperature were optimized using response surface methodology (RSM) after being investigated using OFAT. It can be concluded that EVA had higher capability of reducing wax in two different conditions where the minimum point of wax reduction was found at 400 rpm with 63.5% paraffin inhibition efficiency (PIE) and 10°C with 64.7% of PIE. The amount of waxes collected for each parameter were 0.35 and 0.49 g, respectively. To minimize the wax deposit amount, RSM approach was applied using rotatable central composite design (CCD). The result shows that the amount of wax deposit decreased significantly with the increase of temperature and the stirring rate which were set at 400 rpm and 19°C, rescpectively. The amount of wax deposit was successfully reduced to the minimum value of 0.0095 g after the optimization.

Thermal comfort of dual-chamber ski gloves

In this work, the special design of a pair of ski gloves has been assessed in terms of thermal comfort. The glove 2in1 Gore-Tex has a dual-chamber construction, with two possible wearing configurations: one called “grip” to maximize finger flexibility and one called “warm” to maximize thermal insulation in extremely cold conditions. The dual-chamber gloves has been compared with two regular ski gloves produced by the same company. An intermittent test on a treadmill was carried out in a climatic chamber: it was made of four intense activity phases, during which the volunteer ran at 9 km/h on a 5% slope for 4 minutes, spaced out by 5-min resting phases. Finger temperature measurements were compared with the thermal sensations expressed by two volunteers during the test.

Cold-Blooded Attention: Finger Temperature Predicts Attentional Performance.

Thermal stress has been shown to increase the chances of unsafe behavior during industrial and driving performances due to reductions in mental and attentional resources. Nonetheless, establishing appropriate safety standards regarding environmental temperature has been a major problem, as modulations are also be affected by the task type, complexity, workload, duration, and previous experience with the task. To bypass this attentional and thermoregulatory problem, we focused on the body rather than environmental temperature. Specifically, we measured tympanic, forehead, finger and environmental temperatures accompanied by a battery of attentional tasks. We considered a 10 min baseline period wherein subjects were instructed to sit and relax, followed by three attentional tasks: a continuous performance task (CPT), a flanker task (FT) and a counting task (CT). Using multiple linear regression models, we evaluated which variable(s) were the best predictors of performance. The results showed a decrement in finger temperature due to instruction and task engagement that was absent when the subject was instructed to relax. No changes were observed in tympanic or forehead temperatures, while the environmental temperature remained almost constant for each subject. Specifically, the magnitude of the change in finger temperature was the best predictor of performance in all three attentional tasks. The results presented here suggest that finger temperature can be used as a predictor of alertness, as it predicted performance in attentional tasks better than environmental temperature. These findings strongly support that peripheral temperature can be used as a tool to prevent unsafe behaviors and accidents.

Sensing Cold-Induced Situational Impairments in Mobile Interaction Using Battery Temperature

Previous work has highlighted the detrimental effect of cold ambience on fine-motor skills during interaction with mobile devices. In this work, we develop a method to infer changes in finger temperature of smartphone users without the need for specialised hardware. Specifically, we demonstrate that smartphone battery temperature is a reliable gauge for determining changes to finger temperature. In addition, we show that the behaviour of smartphone battery temperature in cold settings is consistent across different smartphone models and battery configurations. Our method can be used to determine cold-induced situational impairments, and trigger interface adaptations during mobile interaction.

Cardiovascular and thermal strain during 3\u20134\xa0days of a metabolically demanding cold-weather military operation

BackgroundCardiovascular (CV) and thermal responses to metabolically demanding multi-day military operations in extreme cold-weather environments are not well described. Characterization of these operations will provide greater insights into possible performance capabilities and cold injury risk.MethodsSoldiers from two cold-weather field training exercises (FTX) were studied during 3-day (study 1, n = 18, age: 20 ± 1 year, height: 182 ± 7 cm, mass: 82 ± 9 kg) and 4-day (study 2, n = 10, age: 20 ± 1 year, height: 182 ± 6 cm, mass: 80.7 ± 8.3 kg) ski marches in the Arctic. Ambient temperature ranged from −18 to −4 °C during both studies. Total daily energy expenditure (TDEE, from doubly labeled water), heart rate (HR), deep body (Tpill), and torso (Ttorso) skin temperature (obtained in studies 1 and 2) as well as finger (Tfing), toe (Ttoe), wrist, and calf temperatures (study 2) were measured.ResultsTDEE was 6821 ± 578 kcal day−1 and 6394 ± 544 for study 1 and study 2, respectively. Mean HR ranged from 120 to 140 bpm and mean Tpill ranged between 37.5 and 38.0 °C during skiing in both studies. At rest, mean Tpill ranged from 36.0 to 36.5 °C, (lowest value recorded was 35.5 °C). Mean Tfing ranged from 32 to 35 °C during exercise and dropped to 15 °C during rest, with some Tfing values as low as 6–10 °C. Ttoe was above 30 °C during skiing but dropped to 15–20 °C during rest.ConclusionsDaily energy expenditures were among the highest observed for a military training exercise, with moderate exercise intensity levels (~65% age-predicted maximal HR) observed. The short-term cold-weather training did not elicit high CV and Tpill strain. Tfing and Ttoe were also well maintained while skiing, but decreased to values associated with thermal discomfort at rest.

Smartphone-Based Thermal Imaging: A New Modality for Tissue Temperature Measurement in Hand and Upper Extremity Surgeries.

Smartphone-based thermal imaging (SBTI) allows noninvasive temperature measurements. Its validity compared with a conventional infrared probe temperature scanner (IPTS) has not been studied. This study compares temperature measurements between the 2 technologies on human participants. Bilateral index finger temperature measurements were obtained on 30 healthy participants using IPTS and SBTI devices. Dominant versus nondominant sides (side-to-side difference) and individual side measurements between the 2 methods were compared for repeatability (precision) and agreement. A total of 23 female and 7 male participants were tested. Based on nonoverlapping confidence intervals (CIs), intraclass correlation coefficient of repeatability was higher for SBTI than for IPTS measurements in side-to-side differences: 0.97 (95% CI, 0.96-0.99) versus 0.89 (95% CI, 0.82-0.95). The SBTI method recorded higher side-to-side difference and individual side measurements: 0.56°C (limits of agreement [LOA], -1.09°C to 2.20°C) and 2.64°C (LOA, 0.96°C-4.32°C), respectively. In addition to higher precision, SBTI offers added benefits of instantaneous acquisition of the temperature map of the entire hand, allowing quick comparisons of the uninjured and injured fingers. SBTI measurements consistently yielded higher temperature readings in the side-to-side difference as well as individual measurements. This suggested that both devices are not interchangeable for absolute temperature comparisons but are interchangeable in monitoring the changes in temperatures. This study suggests the potential for SBTI devices to be used in the clinical settings and may be of special benefit in telemedicine.

RESPONSE SURFACE METHODOLOGY ON WAX DEPOSIT OPTIMIZATION

In this study, the application of response surface method design based on rotatable central composite design (CCD) was used to optimize wax deposit using Design Expert 7.1.6 software. The process consisted of 13 experiments involving eight factorial points and five replications at the center point. The influence of operating parameters on the weight of wax deposit was investigated using cold finger apparatus. The experimental result indicated that the amount of wax deposit was significant due to factors of cold finger temperature and experimental duration. The wax deposit amount decreased significantly with the decrease of experimental duration when the cold finger temperature increased to 25 °C. The minimum value of 0.0042 g of wax deposit was obtained at the optimized conditions of 1.5 hours and 25 °C, respectively.

Finger cold-induced vasodilation of older Korean female divers, haenyeo: effects of chronic cold exposure and aging.

The aim of the present study was to evaluate the local cold tolerance of older Korean female divers, haenyeo (N=22) in terms of cold acclimatization and ageing. As control groups, older non-diving females (N=25) and young females from a rural area (N=15) and an urban area (N=51) participated in this study. To evaluate local cold tolerance, finger cold-induced vasodilation (CIVD) during finger immersion of 4°C water was examined. As a result, older haenyeos showed greater minimum finger temperature and recovery finger temperature than older non-diving females (P<0.05), but similar responses in onset time, peak time, maximum finger temperature, frequency of CIVD, heart rate, blood pressure, and thermal and pain sensations as those of older non-diving females. Another novel finding was that young urban females showed more vulnerable responses to local cold in CIVD variables and subjective sensations when compared to older females, whereas young rural females had the most excellent cold tolerance in terms of maximum temperature and frequency of CIVD among the four groups (P<0.05). The present results imply that older haenyeos still retain cold acclimatized features on the periphery even though they changed their cotton diving suits to wet suits in the early 1980s. However, cardiovascular responses and subjective sensations to cold reflect aging effects. In addition, we suggest that young people who have been adapted to highly insulated clothing and indoor heating systems in winter should be distinguished from young people who were exposed to less modern conveniences when compared to the aged in terms of cold tolerance.

Music therapy-induced changes in salivary cortisol level are predictive of cardiovascular mortality in patients under maintenance hemodialysis

BackgroundMusic therapy has been applied in hemodialysis (HD) patients for relieving mental stress. Whether the stress-relieving effect by music therapy is predictive of clinical outcome in HD patients is still unclear.MethodsWe recruited a convenience sample of 99 patients on maintenance HD and randomly assigned them to the experimental (n=49) or control (n=50) group. The experimental group received relaxing music therapy for 1 week, whereas the control group received no music therapy. In the experimental group, we compared cardiovascular mortality in the patients with and without cortisol changes.ResultsThe salivary cortisol level was lowered after 1 week of music therapy in the experimental group (−2.41±3.08 vs 1.66±2.11 pg/mL, P<0.05), as well as the frequency of the adverse reaction score (−3.35±5.76 vs −0.81±4.59, P<0.05), the severity of adverse reactions score (−1.93±2.73 vs 0.33±2.71, P<0.05), and hemodialysis stressor scale (HSS) score (−6.00±4.68 vs −0.877±7.08, P<0.05). The difference in salivary cortisol correlated positively with HD stress score scales (r=0.231, P<0.05), systolic blood pressure (r=0.264, P<0.05), and respiratory rates (r=0.369, P<0.05) and negatively with finger temperature (r=−0.235, P<0.05) in the total study population. The 5-year cardiovascular survival in the experimental group was higher in patients whose salivary cortisol lowered by <0.6 pg/mL than that in patients whose salivary cortisol lowered by >0.6 pg/mL (83.8% vs 63.6%, P<0.05).ConclusionProviding music during HD is an effective complementary therapy to relieve the frequency and severity of adverse reactions, as well as to lower salivary cortisol levels. Differences in salivary cortisol after music therapy may predict cardiovascular mortality in patients under maintenance HD.

A 10-day confinement to normobaric hypoxia impairs toe, but not finger temperature response during local cold stress

The study examined the effects of a 10-day normobaric hypoxic confinement on the finger and toe temperature responses to local cooling. Eight male lowlanders underwent a normoxic (NC) and, in a separate occasion, a normobaric hypoxic confinement (HC; FO2: 0.154; simulated altitude ~3400m). Before and after each confinement, subjects immersed for 30min their right hand and, in a different session, their right foot in 8°C water, while breathing either room air (AIR) or a hypoxic gas mixture (HYPO). Throughout the cold-water immersion tests, thermal responses were monitored with thermocouples on fingers and toes. Neither confinement influenced thermal responses in the fingers during the AIR or HYPO test. In the foot, by contrast, HC, but not NC, reduced the average toe temperature by ~1.5°C (p=0.03), both during the AIR and HYPO test. We therefore conclude that a 10-day confinement to normobaric hypoxia per se augments cold-induced vasoconstriction in the toes, but not in the fingers. The mechanism underlying this dissimilarity remains to be established.

Predisposition to out-of-body experience (OBE) is associated with aberrations in multisensory integration: Psychophysiological support from a "rubber hand illusion" study.

It has been argued that disorders in body-ownership and aberrant experiences in self-consciousness are due to biases in multisensory integration. Here we examine whether such biases are also associated with spontaneous out-of-body experiences (OBEs) in a nonclinical population. One-hundred and 80 participants took part in a rubber hand illusion (RHI) experiment with synchronous and asynchronous visual and tactile stimulation. A realistic threat was delivered to the rubber hand after a fixed period of stimulation. Self-report exit questionnaires measured the subjective strength of the illusion and psychophysiological measures (skin conductance responses/finger temperature) provided an objective index of fear/anxiety toward the threat. Control participants reported a stronger RHI, and revealed larger threat-related skin conductance responses during synchronous compared with asynchronous brushing. For participants predisposed to OBEs, the magnitude of the skin conductance was not influenced by brushing synchrony-fear responses were just as strong in the asynchronous condition as they were in the synchronous condition. There were also no reliable effects of finger temperature for either group. Collectively, these findings are taken as support for the presence of particular biases in multisensory integration (perhaps via predictive coding mechanisms) in which imprecise top-down tuning occurs resulting in aberrant experiences in self-consciousness even in nonclinical hallucinators. (PsycINFO Database Record

Decontamination in the Electron Probe Microanalysis with a Peltier-Cooled Cold Finger.

A prototype Peltier thermoelectric cooling unit has been constructed to cool a cold finger on an electron microprobe. The Peltier unit was tested at 15 and 96 W, achieving cold finger temperatures of -10 and -27°C, respectively. The Peltier unit did not adversely affect the analytical stability of the instrument. Heat conduction between the Peltier unit mounted outside the vacuum and the cold finger was found to be very efficient. Under Peltier cooling, the vacuum improvement associated with water vapor deposition was not achieved; this has the advantage of avoiding severe degradation of the vacuum observed when warming up a cold finger from liquid nitrogen (LN2) temperatures. Carbon contamination rates were reduced as cooling commenced; by -27°C contamination rates were found to be comparable with LN2-cooled devices. Peltier cooling, therefore, provides a viable alternative to LN2-cooled cold fingers, with few of their associated disadvantages.

Infrared thermography of human fingers as a method of assessing regional circulation adaptation to blood loss

The aim of the study - to investigate the dynamics of the temperature of fingers and palms in response to short-term ischemia. Materials and methods. The temperature dynamics of fingers and palms was studied with infrared thermal images before, during and after 2 minutes of provocable ischemia in the right hand in 14 healthy volunteers; in 5 blood donors after 400 ml of blood loss; and in 35 patients diagnosed with traumatic hemorrhagic shock. Infrared monitoring of hands temperature was performed by using ThermoTracer TH9100XX (NEC, USA) thermal imager. Ambient temperature of the examination room was 24-25°C, the temperature window of the thermal camera was set to the range of 25 to 36°C. Quantitative data are presented as mean ± standard deviation. Results. During the cuff occlusion test the fingers temperature of the healthy volunteer and blood donors after 60 minutes from collection 400 ml of blood was reduced by more than 0,1°C. After the cuff occlusion test in the pads of the fingers developed local hyperthermia, after 60-90 seconds of their temperature rises above baseline on 0.5-1.5°C, and then restored to the original level values for 3-5 minutes. Patients with hemorrhage by ATLS classification of more than 35% after the termination of cuff occlusion test hyperthermia in the fingertips are not developed, and they remained below baseline over 3-5 minutes the temperature. Conclusions. Changes in local temperature of human fingers after using cuff occlusion test can serve as a criterion for the adaptation of the regional blood flow to the blood loss.