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INTRODUCTION Autologous fat grafting (AFG) is a popular and effective method of breast reconstruction after mastectomy; however, the oncological safety of AFG remains in question. The aim of this study was to determine whether AFG increases the risk of cancer recurrence in the reconstructed breast. METHODS A matched, case-control study was conducted from 2000 to 2017 at the senior author's institution. Inclusion was limited to female patients who underwent mastectomy and breast reconstruction with or without AFG. Data were further subdivided at the breast level. χ analyses were used to test the association between AFG status and oncologic recurrence. A Cox proportional-hazards model was constructed to assess for possible differences in time to oncologic recurrence. The probability of recurrence was determined by Kaplan-Meier analyses and confirmed with log-rank testing. RESULTS Overall, 428 breasts met study criteria. Of those, 116 breasts (27.1%) received AFG, whereas 312 (72.9%) did not. No differences in the rates of oncologic recurrence were found between the groups (8.2% vs 9.0%, P < 1.000). Unadjusted (hazard ratio = 1.03, confidence interval = 0.41-2.60, P < 0.957) and adjusted hazard models showed no statistically significant increase in time to oncologic recurrence when comparing AFG to non-AFG. In addition, no statistical differences in disease-free survival were found (P = 0.96 by log rank test). CONCLUSION Autologous fat grafting for breast reconstruction is oncologically safe and does not increase the likelihood of oncologic recurrence. Larger studies (eg, meta analyses) with longer follow-up are needed to further elucidate the long-term safety of AFG as a reconstructive adjunct.

The deep inferior epigastric perforator (DIEP) flap has become the first choice in autologous breast reconstruction, as excellent aesthetic results can be obtained with minimal donor site morbidity. However, rates of fat necrosis for DIEP breast reconstruction may be as high as 35%, which not only reduces the aesthetic result but also causes uncertainty due to lump formation in the reconstructed breast.1,2 Fat necrosis is a result of inadequate flap perfusion. Selection of a suitable perforator is critical for decreasing the rate of postoperative fat necrosis and minimizing perfusion-related flap complications.3 A thorough understanding of the vascular anatomy and flow characteristics of a selected perforator is essential to balance flap design and adequate flap perfusion. The angiosome concept by Taylor and Palmer has greatly contributed to our knowledge on flap perfusion.4 Saint-Cyr et al introduced in 2009 the perforasome theory and defined a perforasome as the territory perfused by a single perforator vessel of a named artery.5 The importance of finding the most suitable perforator is reflected in the large number of studies on the use of preoperative perforator mapping using imaging techniques.6 Still the relationship between the designed flap size and areas of perfusion from the selected perforator is a clinical challenge because this ratio is unknown.7 To our knowledge there are no in vivo studies that evaluate how the reduction of the number of perforators during flap harvest effects the perfusion area of a selected perforator. Indocyanine green fluorescence angiography (ICG-FA) is an invasive technique that allows for direct visualization of tissue perfusion by registration of intravascular fluorescence intensity. Infrared thermography (IRT) is a noninvasive technique that indirectly visualizes skin perfusion by measuring infrared (IR) radiation released from the skin surface. In static infrared thermography (SIRT), a single image is taken from the area of interest. In dynamic infrared thermography (DIRT), the area of interest is exposed to a mild thermal challenge, and the rate and pattern of temperature changes are recorded and analyzed. ICG-FA and IRT are well-established techniques that provide real-time assessment of skin perfusion and have been shown to provide valuable information for perforator mapping.7–12 The primary aim of this study was to evaluate the effect of perforator dissection on the perfusion area of the selected perforator in a hemi-DIEP flap by using ICG-FA and IRT intraoperatively. The secondary aim of this study was to compare the results from ICG-FA with those obtained from IRT with respect to flap perfusion.

Background: Wound healing problems following abdominoplasty may be a result of impaired tissue perfusion. This study evaluated the impact a standard abdominoplasty may have on abdominal skin perfusion. Methods: A standard abdominoplasty was performed in 16 patients. Dynamic infrared thermography (DIRT) using a mild and a stronger cold challenge was performed pre-, intra-, and postoperatively on day 1, 2, and in week 6. The abdomen was divided into Huger’s vascular zones. A two-tailed t test was used to evaluate differences in mean temperature between zones. Statistical significance was defined as P < 0.05. Results: Two patients suffered wound healing problems. Abdominal skin perfusion showed a hyperaemic state on day 1, day 2, and week 6, postoperatively. Hotspots in zones I and II had all disappeared at the end of surgery and on day 1, except in the cranial part of zone I. Hotspots reappeared in zones I and II during day 2. A statistically significant difference between zones I and II was seen on day 1 and 2, with zone II being cooler. This difference had disappeared in week 6 for the mild cold challenge but not for the stronger cold challenge. Conclusions: A standard abdominoplasty has a significant impact on abdominal skin perfusion. The skin perfusion is a dynamic process with a gradual improvement over time. The strongest effect was seen in zone II near the lower transverse incision line, where skin perfusion was the least. Such may contribute to impaired wound healing at this site

Purpose The American Association of Oral and Maxillofacial Surgeons appointed a task force to study the indications, safety, and clinical practice patterns of cone-beam computed tomography (CBCT) in oral and maxillofacial surgery (OMS). The charge was to review the published applications of CBCT in OMS, identify the current position of academic thought leaders in the field, and research the adoption and usage of the technology at the clinical practitioner level. Materials and Methods This study reviewed the CBCT world literature and summarized published indications for the modality. A nationwide survey of academic thought leaders and practicing oral and maxillofacial surgeons was compiled to determine how the modality is currently being used and adopted by institutions and practices. Results This report summarizes published applications of CBCT that have been vetted by the academic and practicing OMS community to define current indications. The parameters of patient safety, radiation exposure, accreditation, and legal issues are reviewed. An overview of third-party adoption of CBCT is presented. Conclusion CBCT is displacing 2-dimensional imaging in the published literature, academia, and private practice. Best practices support reading the entire scan volume with a written report defining results, patient exposure, and field of view. Issues of patient safety, ALARA (“as low as reasonably achievable”), accreditation, and the legal and regulatory environment are reviewed. Third-party patterns for reimbursements vary widely and seem to lack consistency. There is much confusion within the provider community about indications, authorizations, and payment policies. The current medical and dental indications for CBCT in the clinical practice of OMS are reviewed and an industry guideline is proposed. These guidelines offer a clear way of differentiating consensus medical indications and common dental uses for clinicians. This matrix should bring a predictable logic to third-party authorizations, billing, and predictable payments for this emerging technology in OMS.

Background: Dynamic infrared thermography (DIRT) is a noninvasive imaging technique that can provide indirect and real-time information on skin perfusion by measuring skin temperature. Although used in flap surgery, there are no reports on its value in procedures using a pedicled thoracodorsal artery perforator (TDAP) flap. The aim of this study was to assess the usefulness of DIRT in preoperative perforator mapping and in monitoring intra- and postoperative flap perfusion of pedicled TDAP flaps. Methods: This prospective study comprised 21 patients (21 flaps) scheduled for reconstructive surgery with a TDAP flap. Perforator mapping was done by DIRT, handheld unidirectional Doppler ultrasound, and computer tomography angiography. Intra- and postoperative flap perfusion was assessed by clinical signs and with the use of DIRT and handheld unidirectional Doppler ultrasound. Results: Perforator mapping with DIRT showed that first-appearing bright hotspots were always associated with arterial Doppler sounds and suitable perforators intraoperatively. Computer tomography angiography presented useful information on the thoracodorsal artery branching pattern but was less beneficial for perforator mapping. Intra- and postoperative flap monitoring with DIRT was more useful than handheld unidirectional Doppler ultrasound and clinical signs to detect early arterial and venous perfusion problems. DIRT demonstrated that TDAP flap perfusion is a dynamic process with an increase in perfusion during the first operative days. Nineteen flaps survived, of which 3 sustained distal necrosis. Two flaps were lost due to inadequate blood perfusion. Conclusion: DIRT provides valuable real-time information for perforator mapping and for monitoring TDAP flap perfusion intra- and postoperatively.

The following article, Norheim, A.J., Borud, E., Wilsgaard, T., DeWeerd, L. & Mercer, J.B. (2018). Variability in peripheral rewarming after cold stress among 255 healthy Norwegian army conscripts assessed by dynamic infrared thermography. International Journal of Circumpolar Health, 77(1), can be accessed at https://doi.org/10.1080/22423982.2018.1536250. Exposure to cold climate is an inevitable consequence of military training in Norway. Adequate peripheral microcirculation in the extremities is important to maintain temperature, and to protect against freezing cold injuries. The aim of this study was to investigate the variability in skin rewarming ability. The study subjects consisted of 260 healthy Norwegian army conscripts, following a mild cold provocation test (hands immersed in 20°C water for 1 min) using dynamic infrared thermography (DIRT). Thermal images were obtained to investigate any differences in skin rewarming ability of the hand (fingers). DIRT took place under standardised and stable study conditions. Conscripts were characterised as either slow, intermediate or rapid rewarmers. While 90% could recover, partially or completely, within 4 min to the skin temperature values before the provocation test, 10% showed a slow rewarming pattern. In the slow rewarmers, the rewarming ability was correlated with a low average temperature of the hands prior to the cooling test. The healthy young army conscripts in this study showed a large variability in their rewarming ability following a standardised mild cold provocation test.

While health risks from smoking cigarettes are well known, little is known about the health risks of using smokeless tobacco (ST). The aim of this study was to evaluate the effect that ST in the form of oral use of snus with nicotine and snus without nicotine has on peripheral skin blood circulation. 21 young habitual users of snus with nicotine participated in this study. Under controlled conditions the subjects were exposed to a 30 minute period of oral use of snus with nicotine (SN+) and snus without nicotine (SN-). The peripheral skin blood circulation was indirectly monitored on the hands by measuring skin temperature using infrared thermography. The skin blood circulation in the hands showed a statistical significant decrease in the SN+ experiments, while skin blood circulation was hardly effected in the SN- experiments. It is concluded that the use of smokeless tobacco in the form of oral use of snus containing nicotine causes a decrease in peripheral skin blood circulation while such an effect is not seen in snus without nicotine. This knowledge may be of use when treating patients that require adequate peripheral skin circulation or in the military when soldiers are exposed cold conditions.

Observations of the spread of wander-corrected averaged pulses propagated over 510 km for 54 h in the Philippine Sea are compared to Monte Carlo predictions using a parabolic equation and path-integral predictions. Two simultaneous m-sequence signals are used, one centered at 200 Hz, the other at 300 Hz; both have a bandwidth of 50 Hz. The internal wave field is estimated at slightly less than unity Garrett-Munk strength. The observed spreads in all the early ray-like arrivals are very small

Source: doi: 10.1007/s00784-016-1962-5 Objectives:To investigate how heat development in the pulp chamber and coronal surface of natural teeth with and without cusps subjected to irradiance using light-emitting diode (LED)–light-curing units (LCUs) is associated with (i) irradiance, (ii) time, (iii) distance, and (iv) radiant exposure. Materials and methods:Three different LED-LCUs were used. Their irradiance was measured with a calibrated spectrometer (BlueLight Analytics Inc., Halifax, Canada). An experimental rig was constructed to control the thermal environment of the teeth. The LED-LCU tip position was accurately controlled by a gantry system. Tooth surface temperature was measured by thermography (ThermaCAM S65 HS, FLIR Systems, Wilsonville, USA) and pulp chamber temperature with a thermocouple. LED-LCU tip distance and irradiation times tested were 0, 2, and 4 mm and 10, 20, and 30 s, respectively. Ethical permission was not required for the use of extracted teeth. Results:Maximum surface and pulp chamber temperatures were recorded in tooth without cusps (58.1 °C ± 0.9 °C and 43.1 °C ± 0.9 °C, respectively). Radiant exposure explained the largest amount of variance in temperature, being more affected by time than irradiance. Conclusions:At all combinations of variables tested, repeated measurements produced consistent results indicating the reliability of the method used. Increased exposure time seems to be the factor most likely to cause tissue damage. Clinical relevance:Risk of superficial tissue damage at irradiances >1200 mW/cm2 is evident. There is a risk of pulp damage when only thin dentin is left at higher irradiances (>1200 mW/cm2). Clinicians should be aware of LED-LCU settings and possible high temperature generated.

This article describes how dynamic infrared thermography (DIRT) can be used in autologous breast reconstruction with a deep inferior epigastric perforator flap. This noninvasive and noncontact technique for indirect monitoring of skin blood perfusion can be used in the preoperative planning and intraoperative evaluation of flap perfusion, as well as the postoperative monitoring of perfusion dynamics of DIEP flaps. DIRT provides valuable information on the perfusion physiology of perforators.

The aim of this paper is to evaluate dynamic infrared thermography (DIRT) as a technique to assist in preoperative perforator selection and planning of free deep inferior epigastric perforator (DIEP) flaps. Twenty-seven patients, scheduled for secondary autologous breast reconstruction with either a free DIEP flap or superficial inferior epigastric artery flap, were included in this prospective clinical study. Preoperative mapping of perforators was performed with a hand-held Doppler and DIRT. A multidetector computer tomography scan was additionally carried out in the last 8 patients. In 23 patients a DIEP flap was used. The perforator as selected from DIRT was a suitable perforator in all DIEP flaps. The location and quality of the selected perforator from DIRT corresponded well with the multidetector computer tomography scan results. Preoperative perforator selection and planning of DIEP flaps is facilitated with the use of DIRT. The technique is noninvasive and easy to use.

Seasonal variations in mortality occur throughout Europe as well as in other parts of the world, such as Japan, China and the southern hemisphere1–6 with a higher death rate in the winter (excess winter deaths). Mortality from cardiovascular disease (CVD) accounts for the majority of the excess winter deaths (up to 70% in some countries), while up to about half of the remaining may be accounted for by increases in respiratory disease.3,7 The majority of deaths from CVD occur in the elderly. For example, in Norway, CVD, including ischaemic heart disease and cerebrovascular disease, accounts for about 46% of all causes of death. About 90% of all CVD-related deaths occur in people who are ≥65 years. Cold exposure related to winter mortality from ischaemic heart disease, cerebrovascular disease, respiratory disease, and all causes in warm and cold regions of Europe have been previously investigated in a large European Economic Community supported study.7 The main findings of this study was that mortality increased to a greater extent with a given fall in temperature in regions with warm winters, in populations with cooler homes, and among people who wore fewer clothes and were less active outdoors. Similar findings regarding excess winter mortality were found in a comparative study between Norway and the Republic of Ireland, two countries that were not investigated in the Eurowinter study.6,8 A comparison of these two countries is of interest since they are demographically similar with respect to CVD mortality, but have different climates. In 1993, the population of Norway and the Republic of Ireland was 4 312 000 and 3 563 000, respectively and in both countries mortality due to CVD, accounted for approximately the same percent of deaths (1985–93: Norway 45% and Ireland 47%.6 Seasonal variation in …

Perfusion dynamics of 16 free DIEP flaps and 4 free SIEA flaps were studied during the first, third, and sixth postoperative day using dynamic infrared thermography (DIRT). For both flap types the zone positioned over the perforator is perfused first, followed by the adjacent ipsilateral zone, and finally the contralateral zones. Perfusion of the subdermal plexus of all zones preceded the perfusion of the subcutaneous layer of all zones. While the initial hyperemia subsided with time, the total number of hot spots increased with time. Perfusion of free DIEP and SIEA flaps during the first postoperative week is a dynamic process. The perfusion shows a stepwise progression at the level of the subdermal plexus and at the level of the subcutaneous layer each with its own time sequence and with the midline as an area of resistance for circulation.

This experimental study compared the direct technique indocyanine green fluorescence angiography (ICG-FA) and the indirect technique dynamic infrared thermography (DIRT) for visualising skin perfusion. Eight isolated human transverse abdominal skin flaps, obtained from female patients undergoing abdominoplasty, were used. A total of 19 selected vessels were individually perfused. Warm and cold perfusate was used for visualising skin perfusion with DIRT. Both techniques were tested for repeatability, making up a total of 34 perfusions. Qualitative analysis of the rate and pattern of perfusion visualised by both techniques was carried out. The extent of the perfused area indicated by the indirect DIRT technique corresponded well with the perfused area indicated by the direct ICG-FA technique. The appearance of distinct hot spots in the IR images provided additional information on the distribution of perforating vessels. It is concluded that in experimental situations the non-invasive DIRT technique is a good alternative to the invasive ICG-FA technique for visualising skin perfusion.

Background Recalcitrant lateral epicondylitis (elbow tendinosis) is a common cause of elbow pain. There are many forms of treatment, none being superior. Hypothesis The main hypothesis tested in this study is that radiofrequency microtenotomy offers better results than the extensor tendon release and repair operation for elbow tendinosis, especially earlier recovery. Study Design Randomized controlled trial; Level of evidence, 1. Methods Twenty-four patients were randomized into 2 treatment groups, extensor tendon release and repair, and microtenotomy. Dynamic infrared thermography (DIRT) was employed as an objective method to verify the diagnosis as well as to document the outcome 3 months after the surgical procedure. Results Visual analog scale pain scores in the microtenotomy but not in the release group decreased significantly after 3 weeks. There was no statistically significant difference in pain scores between the 2 groups at 3, 6, and 12 weeks, and at 10 to 18 months. At 12 weeks, grip strength had improved significantly in the microtenotomy but not in the release group. The functional score was significantly increased in both groups. The DIRT group showed significant differences in epicondyle skin temperature between diseased and normal elbows both pre- and postoperatively. Abnormal DIRT images correlated well with elevated pain scores. Conclusions Radiofrequency microtenotomy provides a promising alternative to the release operation for elbow tendinosis. Dynamic infrared thermography provides a reliable, noninvasive, objective method for the diagnosis of elbow tendinosis, as well as for evaluation of the outcome following treatment.

Inadequate perfusion is the most common cause of partial flap loss in reconstructive surgery. Intraoperative monitoring of flap perfusion may prevent such loss. This study compared indocyanine green fluorescence angiography (ICG-FA) and dynamic infrared thermography (DIRT) in their ability to predict intraoperatively the percentage of flap survival in a caudally based McFarlane flap in 10 male Wistar rats. The intraoperative images of both techniques were subjectively and objectively analysed. The percentage of flap survival, as judged from the digital colour photographs 7 days post-operatively, was 69 ± 3%. Objective analysis of flap survival based on intraoperative DIRT and ICG-FA (74 vs 63%, respectively) correlated quite well with the subjective measurements (75 ± 2 vs 59 ± 4%, respectively). However, intraoperative ICG-FA images underestimated flap survival by 6–10%, while intraoperative DIRT images overestimated the flap survival by 5–6%. The authors conclude that intraoperative use of ICG-FA and DIRT can provide valuable information on areas with inadequate perfusion as long as their limitations are respected.

The purpose of the study was to examine the effect of a 12 h period of abstinence from smoking in young and old habitual smokers, on skin rewarming patterns of a hand following local cooling. This was done by comparing changes in peripheral circulation, measured indirectly by monitoring changes in skin surface temperatures of the hand with both infrared (IR) thermography and thermocouples before, during and after immersing the right hand for 2 min in water at 10 degrees C. Included in the study were young male non-smokers (n = 14) and smokers (n = 13), and elderly non-smokers (n = 12) and smokers (n = 14). The results showed no statistically significant difference between young non-smokers and smokers when comparing their response to the local cold challenge. The elderly smokers had a significantly higher hand skin temperature prior to cooling (34.0 +/- 0.2 degrees C) and after 80% rewarming (32.1 +/- 0.2 degrees C) (i.e. when the skin temperature in the "cooled" hand has regained 80% of the cold induced drop in temperature), compared to elderly non-smokers (33.3 +/- 0.2 and 31.3 +/- 0.2 degrees C, respectively). The elderly smoking subjects also had a faster recovery after cooling (9.7 +/- 0.8 min) than the elderly non-smoking subjects (16.7 +/- 2.6 min). A follow-up study with seven elderly smokers, who had smoked as usual until 2 h before the experiment, showed responses lying between the non-smokers and smokers who had had a longer period of abstinence (12 h) from smoking. In conclusion, we have demonstrated using IR-thermal imaging that elderly subjects who have smoked for many years have slightly warmer hand skin temperature when they abstain from smoking. Even a period of abstinence from smoking of a few hours can affect the way in which elderly subjects respond to a local cold challenge, recovering more rapidly then their non-smoking counterparts.

Cardiovascular diseases (CVD) are responsible for around 20% of all deaths worldwide (approximately 14 million) and are the principal cause of death in all developed countries, accounting for 50% of all deaths. Variations in the annual per capita death rates in different countries are well documented. Less well known are seasonal variations in death rates, with the highest levels occurring during the colder winter months, which have been described in many countries. This phenomenon is referred to as excess winter mortality. CVD-related deaths account for the majority of excess winter deaths (up to 70% in some countries), while about half of the remaining are due to increases in respiratory diseases. Paradoxically, CVD mortality increases to a greater extent with a given fall in temperature in regions with warm winters. While much of the indirect evidence points to the notion that cold is somehow involved in explaining excess winter deaths, the mechanism by which seemingly mild exposure to cold ambient conditions can increase the risk of death remains unclear. The strong indirect epidemiological evidence coupling cold climate to mortality may be related to indoor rather than outdoor climatic conditions (e.g., cold/damp houses versus warm/dry houses) coupled with a plethora of factors including health status, ageing-related deterioration in physiological and behavioral thermoregulation, toxicology, and socioeconomic factors.

Twelve captive wild-caught adult arctic foxes (Alopex lagopus) were anesthetized a total of 24 times for an equal number of surgical procedures involving implantation of heart rate (HR) and core body temperature transmitters (Tb) between October 1995 and April 1997. Xylazine–ketamine and medetomidine–ketamine anesthesia was used, resulting in an unacceptably high death rate. One out of four foxes anesthetized with xylazine–ketamine died, whereas two of nine foxes anesthetized with medetomidine–ketamine died out of a total of 20 surgical procedures. Durations of the surgeries for implantation of Tb transmitters and HR transmitters were 73 ± 7 min and 95 ± 13 min, respectively.

Background:. Wound healing problems at the donor site in free abdominal flap breast reconstruction cause significant morbidity to patients. No studies have investigated what impact the use of the internal mammary artery in free abdominal flap breast reconstruction has on abdominal skin perfusion. We hypothesized that harvesting the internal mammary vessels (IMV) has a negative effect on abdominal skin perfusion. Methods:. The abdomen and anterior thoracic wall of 17 patients scheduled for secondary free abdominal flap breast reconstruction using IMV was pre-, intra-, and postoperatively examined with dynamic infrared thermography. Qualitative and quantitative analyses of the rate and pattern of recovery in Huger’s vascular zones were made with each patient being its own control. Zone III on the side where IMV were used was numbered zone IV. The contralateral zone III was used as reference. Results:. Postoperative abdominal skin perfusion in zone IV was always significantly reduced compared with zone III (1-tailed t test, P < 0.05). The difference between zones II and III was statistically significant for day 1 and 3, but not for day 6 (2-tailed t test, P < 0.05). Skin perfusion in zones II and IV increased during consecutive postoperative days with an increase of hot spots in these areas. Conclusions:. Using the IMV in free abdominal flap breast reconstruction had a significant effect on abdominal skin perfusion and may contribute to abdominal wound healing problems. The reperfusion of the abdominal skin was a dynamic process showing an increase in perfusion in the affected areas during the postoperative days.

Source at https://doi.org/10.1080/22423982.2016.1273677. Frostbite sequelae are a relevant occupational injury outcome for soldiers in arctic environments. A Caucasian male soldier suffered frostbite to both hands during a military winter exercise. He developed sensory-motor disturbances and cold hypersensitivity. Angiography and thermography revealed impaired blood flow while Quantitative Sensory Testing indicated impaired somato-sensory nerve function. Two years after the initial event, he received an off label treatment with Botulinum toxin distributed around the neurovascular bundles of each finger. After treatment, cold sensitivity was reduced while blood flow and somato-sensory nerve function improved. The successful treatment enabled the soldier to successfully pursue his career in the army.

Bare pig skin emissivity at shoulder, udder and ear base was found to be 0.96-0.98.Hairs lowered the emissivity by 0.018?0.010 (p=0.070).Skin emissivity was reduced by 0.012?0.006 (p=0.062) with no blood perfusion. Infrared thermography may be used for pig health screening and fever detection. In order to achieve the necessary accuracy for this purpose, it is necessary to know emissivity of the skin surface. Previous investigations attempting to find the emissivity of pig skin revealed numbers from 0.8 to 0.955. Such discrepancies can result in measured surface temperatures differing by several degrees Celsius. An unacceptable discrepancy if used for fever screening.In this study we determined the emissivity of three skin locations in ten sows when they were alive and dead: the ear base, udder and shoulder. The shoulder was investigated with and without (clipped) hairs.Emissivity for ear base, udder, and shoulder (hairy) was 0.978?0.006, 0.975?0.006 and 0.946?0.006, respectively. Clipping the hairs of the shoulder tended to increase the emissivity (p=0.07). Emissivity of the hairy shoulder was significantly lower than for the ear base (p

The terms infrared thermography and infrared thermal imaging are common terms used when visualising and quantifying skin surface temperature using infrared cameras. In healthy subjects, the pattern of skin surface temperature in the same body area on contralateral sides of the body is regarded by many as being very similar. Arising from this the terms thermal symmetry (reflecting normal physiology) and thermal asymmetry (reflecting abnormal physiology) have arisen, the latter being often used in helping medical practitioners to make a diagnosis. However, these terms mean different things to different people and there is some confusion about their use. In this short communication we explain why this has come about.

BACKGROUND: Seasonal variations in mortality resulting from cardiovascular diseases (CVD) have been demonstrated in many countries, with the highest levels observed during the coldest months of the year. We studied the seasonal changes in CVD mortality in Norway and the Republic of Ireland, two countries which are demographically quite similar, but climatically different; we also examined the relation between CVD mortality and air temperature. METHODS: Registered monthly data for mortality from CVD for the period 1985-1995 were obtained from the Norwegian Central Bureau of Statistics and the Irish Central Statistics Office. Meteorological data were provided by the Norwegian Institute of Meteorology and Met Eireann, in Ireland. Monthly mortality ratio for both men and women aged 60 and older was calculated from the mortality date. Mean monthly air temperatures for the two countries were calculated from the meteorological data. RESULTS: For the 10-year period investigated, the lowest and highest monthly mortality ratios were on average found in August and January, respectively, and mean excess winter mortality, expressed as the difference between the August and January values for the entire 10-year period, was 22% (Norway) and 35% (Ireland). However, when the percentage difference in the months with the respective highest and lowest mortality ratios were calculated for each year, the average of these differences for each of the 10 individual years was 29% and 45%. Mortality ratio was found to increase much more steeply with decreasing air temperature in Ireland than in Norway. CONCLUSION: Although the seasonal variation between CVD mortality in both countries is similar, the different relation with climatic conditions may result from differences in housing standards, allowing outdoor temperatures to have a greater influence on indoor temperature in Ireland than in Norway.

The Strategic Environmental Research and Development Program (SERDP) and the Environmental Security Technology Certification Program (ESTCP) are the Department of Defense's (DoD) environmental research programs (herein referred to as The Programs ), harnessing the latest science and technology to improve DoD s environmental performance, reduce costs, and enhance and sustain mission capabilities. The Programs fund basic and applied research as well as field demonstration and validation efforts. For additional information, refer to www.serdp-estcp.org. This workshop focused on the research needed to more efficiently deal with the long term management and lengthy restoration of complex sites, with overall objectives to (1) review the current status of complex sites, expectations for restoration, and how they are managed, (2) identify options for achieving restoration goals more efficiently over longer periods of time, (3) prioritize the research and demonstrations needed to show that restoration goals can be achieved more efficiently over longer periods of time, and to develop the new technologies needed to support that paradigm, and (4) promote cooperation with other federal agencies to fund the needed work most efficiently. Approximately 60 invited personnel representing DoD remedial program managers (RPMs), federal and state regulators, engineers, researchers, industry representatives, and consultants were in attendance. Two breakout sessions, each with four working groups, facilitated discussions of the current state of the science and ranking of research, demonstration and technology transfer needs for four areas: enhanced attenuation, long term monitoring, predictive modeling, and emerging contaminants. The research, demonstration and technology transfer needs were prioritized in each work group (Table E-1).

Most marine sediments exhibit transverse isotropy (TI) that can have a significant effect on the signal properties of strongly bottom interacting sound. Locally, transverse isotropy has the greatest effect on the fundamental and near fundamental modal overtones. The local shallow water TI modes have reduced amplitude in the sediment relative to the corresponding shallow water modes for an isotropic bottom. Even a small departure from isotropy (2.4%) can have a significant (15%) effect on the phase velocity of bottom interacting modes. Calculations of mode–mode coupling coefficients for a range‐dependent medium indicate that mode coupling is more strongly confined to modal nearest neighbors for a TI medium characterized predominantly by shear wave anisotropy, when compared to the corresponding isotropic medium. As the frequency increases, the strongest coupling occurs between higher overtones and also becomes more strongly peaked around nearest neighbors. The coupled mode theory of Maupin [Geophys. J. 93, 173–185 (1988)] is employed to model the coupling. This theory can treat smooth gradients and sloping layer boundaries for all five of the bottom elastic moduli in a TI medium, the densities, and the range dependence of the water column itself. This coupled mode formulation also properly accounts for the continuity of stress and displacement boundary conditions in an exact way at irregular interfaces.

Malaise and fainting are unpleasant acupuncture adverse effects. This paper shows how the use of thermography might identify subjects before the systematic responses become clinically significant.

A 1000‐km acoustical transmission experiment has been carried out in the North Pacific, with pulses broadcast between a moored broadband source (250‐Hz center frequency) and a moored sparse vertical line of receivers. Two data records are reported: a period of 9 days at a pulse rate of one per hour, and a 21‐h period on the seventh day at six per hour. Many wave‐front segments were observed at each hydrophone depth, and arrival times were tracked and studied as functions of time and depth. Arrivals within the final section of the pulse are not trackable in time or space at the chosen sampling rates, however. Broadband fluctuations, which are uncorrelated over 10‐min sampling and 60‐m vertical spacing, are observed with about 40 (ms)2 variance. The variance of all other fluctuations (denoted as low‐frequency) is comparable or smaller than the broadband value; this low‐frequency variance can be separated into two parts: a wave‐front segment displacement (with vertical correlation length greater than 1 km) that varies substantially between rays with different ray identifiers, and a distortion (with vertical correlation length between 60 m and 1 km) of about 2 (ms)2 variance. The low‐frequency variance may be explained as the effect of internal waves, including internal tides. The variance of the broadband fluctuations is reduced somewhat but not eliminated if only high‐intensity peaks are selected; this selection does not affect the statistics of the low‐frequency fluctuations.

The United States government needs to plan for and prepare against terrorist attacks. Terrorism, when combined with weapons of mass destruction, increases the planning complexity. In the event of a nuclear terrorist attack, the government will need to conduct consequence management in the affected areas, govern the non-affected areas, and prevent future attacks. This paper examines what actions, following a nuclear terrorist attack on domestic soil, produce the broadest and deepest results and what options the President has to address such a national emergency. The federal government must address the national effects caused by the attack itself as well as the anticipated results caused by communities enacting protective measures at the detriment of their neighbors. To produce the list of coordinated actions and options, this paper uses a scenario where a terrorist loads a 10-kiloton (kt) weapon into a truck, drives it to the nation's capital, and detonates it. After detonation, the government must attempt to mitigate the weapon's real and perceived effects. A review of the mitigating responses reveals that some actions are nearly impossible without prior planning and coordination. Additionally, the government must operate within a framework of constitutionally granted authorities. Continuity of government is assumed sufficient to exercise command and control and is beyond the scope of this paper. It is also beyond the scope of this paper to present more than a cursory overview of preventing a subsequent attack.

Flap failure in free-tissue transfer relates strongly to technical failure of the anastomosis or to kinking as well as to external compression of the donor or recipient vessels. Intraoperative monitoring of flap perfusion has shown to prevent flap failure. This prospective, clinical study presents the results of intraoperative dynamic infrared thermography as a novel method to monitor reperfusion indirectly in 10 free flaps. This noninvasive technique provided a fast and reliable method to register partial or total arterial occlusion due to anastomotic failure, as well as due to external compression or kinking of the vessels. The dynamic infrared image sequences showed an improved rate and pattern of rewarming of the flap after an additional venous anastomosis was opened. The state of reperfusion of the flap at the end of the operation could easily be determined. The authors conclude that dynamic infrared thermography provides the surgeon with valuable information on flap reperfusion during free flap surgery.

Background. In this study we have investigated the effect of cold exposure on young healthy subjects, with particular emphasis on the hematological system. Study design. The lightly clothed subjects were seated in a thermally controlled climatic chamber for three hours. Methods. One group (control) was exposed to three hours at 28 °C, while the other group was first exposed to one hour at 28 °C, and then two hours of decreasing temperature, ending at 6 °C. Mean body temperature decreased, blood pressure increased, and metabolism increased by 60 % in the cold exposure group compared to the control group. Blood samples were taken through an arterial catheter every hour during the exposure, one hour before and 1.5, 3 and 25 hours after the exposure. Results. Red blood cell counts increased, due to hemo-concentration. In the cold neutrophil counts did not increase during the day, but were stable at a lower level compared to the controls. Conclusions. It is suggested that the cold induced decrease in neutrophil count is caused by an activation and increased adhesion of the neutrophils to the endothelial wall. This finding is supported by the cold exposure-induced increases in IL-8 and Thromboxane B2 in LPS-stimulated blood, and an increase in the plasma concentration of P-selectin. (Int J Circumpolar Health 2004; 63(2):115-128) Keywords: blood factors, cell counting, cold exposure, P-selectin

The Acoustic Thermometry of Ocean Climate project (ATOC) is just beginning. The goal of the project is to determine over the course of a decade if the oceans are warming or cooling and if numerical models can be validated. Long range acoustic transmissions between various sources and receivers will be monitored to determine if travel times and the sound speed and temperature, change over these time scales. A good design of the global acoustic array will optimize the detection versus cost ratio and is therefore essential to the success of the project. It depends on a variety of factors including spatial structure of the expected signals, logistics and cost of cabled sources, number and distribution of receivers, to name a few. The subject of this paper is an interactive software package that is being constructed to assist in this global array design process. >

Moving ship tomography measures acoustic travel times between transmitters moored above the ocean floor and hydrophones on a cable tethered to a ship. The authors consider a Kalman filter that determines the location of a subarray of the hydrophones near the end of the cable. A long-baseline tracking system, consisting of floating buoys and the ship, acoustically measured the slant range to each hydrophone. The range to orbiting satellites was measured with the Global Positioning System (GPS). A short-baseline acoustic system measured range and direction from the ship to a beacon on the cable, and to each buoy. Depths at various points near the hydrophones were measured using three different pressure sensors. The Kalman filter combines these primary measurements and some supporting measurements to form an estimate of the buoy and hydrophone locations. An iterated correction step is used to adjust for the nonlinearities and an outlier detection scheme to make the filter robust. >

Background Seasonal variations in mortality due to cardiovascular disease have been demonstrated in many countries, with the highest levels occurring during the coldest months of the year. It has been suggested that this can be explained by cold climate. In this study, we examined the relationship between mortality and two different climatic factors in two densely populated areas (Dublin, Ireland and Oslo/Akershus, Norway). Methods Meteorological data (mean daily air temperatures and wind speed) and registered daily mortality data for three groups of cardiovascular disease for the period 1985-1994 were obtained for the two respective areas. The daily mortality ratio for both men and women of 60 years and older was calculated from the mortality data. The wind chill temperature equivalent was calculated from the Siple and Passels formula. Results The seasonal variations in mortality were greater in Dublin than in Oslo/Akershus, with mortality being highest in winter. This pattern was similar to that previously shown for the two respective countries as a whole. There was a negative correlation between mortality and both air temperature and wind chill temperature equivalent for all three groups of diseases. The slopes of the linear regression lines describing the relationship between mortality and air temperature were a lot steeper for the Irish data than for the Norwegian data. However, the difference between the steepness of the linear regression lines for the relationship between mortality and wind chill temperature equivalent was considerably less between the two areas. This can be explained by the fact that Dublin is a much windier area than Oslo/Akershus. Conclusion The results of this study demonstrate that the inclusion of two climatic factors rather than just one changes the impression of the relationship between climate and cardiovascular disease mortality.

Accidental hypothermia in human subjects can occur almost anywhere in the world, even in those areas with the hottest climates, for example, because of industrial accidents. However, on a day-to-day basis the potential risk of being subjected to accidental hypothermia is greatest for those living and working at high latitudes, with cold water immersion representing the most extreme challenge. Although most of the effort concerned with protection against cold exposure has involved finding ways of decreasing heat loss by improving insulation, some attempts have been made at finding ways of improving cold tolerance by modifying the thermoregulatory response to cold. The main strategies that have been used are thermal acclimation, physical exercise, dietary enhancement of thermogenesis, pharmacological enhancement of thermogenesis, and manipulation of thermoregulatory set point. This chapter briefly reviews the success of these strategies. Although none of the strategies examined has resulted in concrete methods that are routinely used to improve cold tolerance, it is concluded that the pharmacological enhancement of cold thermogenesis using ephedrine in combination with methylxanthine represents the most promising method for delaying the onset of hypothermia in humans.

The presence of nonaqueous-phase liquids (NAPLs) in a wide range of contaminated sites has created the need for a thorough understanding of the relevant characteristics and processes. Over the years, many models have been developed to improve this understanding and help design effective remedial strategies. This chapter is an introduction to the existing and ever-expanding choice of models that deal with multiphase flow problems. Most models currently available are limited in the type of remediation technologies that may be simulated; hence, the discussion is categorized according to the type of technology. An overview familiarizes the reader with the various chemical and physical phenomena that are pertinent to these models. Almost all modeling applications still require some simplifying assumptions, which must be carefully selected and evaluated. It is crucial to clearly understand the effect of making certain assumptions on the modeling outcome. Two case studies of model application to realworld contaminated sites are presented to highlight the importance of adequate selection of models and key simplifying assumptions.

The prototype Pacific Ocean network for the Acoustic Thermometry of Ocean Climate (ATOC) program consists of two shore-cabled acoustic sources, two autonomous vertical hydrophone receiving arrays, and 16 U.S. Navy hydrophone arrays. The sources, receivers, and signaling strategy are designed to be capable of up to 10-megameter transmissions on a routine basis. A new broadband, low-frequency (75 Hz), acoustic source was designed and built by Alliant Techsystems. The bender-bar/barrel-stave transducer is pressure compensated for operation to 1000-m depth. Signal waveform shaping is employed to broaden the effective bandwidth of the source to 37.5 Hz (Q=2; time resolution of 27 ms). Four-element vertical hydrophone arrays are attached to the sources to permit reciprocal transmissions and ambient noise monitoring. Autonomous vertical hydrophone arrays consisting of 40 elements at 35-m spacing (1400-m aperture) were developed to resolve low-order acoustic modes. The autonomous arrays are designed for deployments of up to 1 year, with intermediate readout of the data via ship-recoverable pop-up data modules. The U.S. Navy hydrophone arrays were instrumented with 80486-based data acquisition and processing systems, with communications links for transmitting the data in near real time to a central site for further processing and archiving.

INTRODUCTION: Multidetector computed tomography (MDCT) angiography is “the gold standard” for preoperative perforator selection. DIRT is based on the relationship between dermal perfusion and the change in rate and pattern of skin rewarming following a cold challenge. Can DIRT be an alternative to MDCT? METHODS AND MATERIALS: 23 patients scheduled for breast reconstruction with DIEP flap were included. Preoperatively arterial perforator sounds were located with a hand held Doppler. Afterwards a desktop fan was used to deliver a mild cold challenge to the lower abdomen. The rate and pattern of rewarming of the skin was registered with an infrared camera. The locations of first appearing hot spots on the skin were registered. Eight patients had an additional MDCT scan. RESULTS: A rapid appearing “hot spot” was associated with an arterial Doppler sound and a suitable perforator intraoperatively. All DIEP flaps survived and were based on the perforator as selected from DIRT. The selected hot spot could easily be related to a perforator on the MDCT scan. CONCLUSION: Perforator selection of DIEP flaps is facilitated with the use of DIRT. The technique is non-invasive, provides real-time information and does not require exposure to ionizing radiation or intravenous contrast medium. DIRT could be an alternative for MDCT in perforator selection.