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Electrical stimulation is a widely used modality in the field of physical therapy and exercise physiology. The most common method for the application of electrical stimulation is a two-electrode system where one electrode is the source and the other is a reference. However, recent studies report that a more effective delivery system can be achieved if more than two electrodes are used. In the present investigation, the circuitry to deliver electrical stimulation through a 2-, 3- or 4-electrode delivery system was designed. The system was evaluated by its ability to deliver current on the surface of the skin as well as deep into the quadriceps muscle in six control subjects and in and around wounds in six other subjects. The results of the experiments showed that much better depth of penetration was achieved in a 4-electrode system (one electrode was on the opposite side of the limb and three electrodes were on top of the limb) than in either a 2- or a 3-electrode delivery system. In non-wounded skin, given the same current from the stimulator, the current in the quadriceps muscle was found to be double with a 4-electrode versus a 2-electrode system. In wounds, this same finding was seen. Here, blood flow, an indicator of the effectiveness of electrical stimulation in wounds, was three times higher if a multi-channel stimulator was used versus a 2-channel stimulator. Thus a multi-channel electrical stimulation system is more effective than a 2-electrode system. [ABSTRACT FROM AUTHOR]

Nursing research activity by clinicians has increased in volume in the last few years, due to an increased awareness of the importance of evidence-based practice, the shift of nurse education into higher education establishments and the emergence of new nursing roles which demand research activity as a central domain of the role. This paper will report on the results of a study examining nursing research activity in the UK National Health Service and will present data examining the perceptions and experiences of nurses undertaking research. Forty-eight research-active nurses in five NHS organisations were interviewed. Data were analysed using the Framework approach. Four main themes emerged: perceptions of nursing research, NHS influences, support systems and individual influences. Many factors were identified by nurses that influenced their experiences and perceptions, and nurses frequently reported difficulties in being able to conduct research in the clinical area. Dissemination via publication was rare. Personal sacrifices were common and nurses felt that these were not recognised by managers. Nurses undertaking research need more structured support systems and recognition of the value of nursing research. Individualised help from more experienced researchers for support and to disseminate findings is recommended. [ABSTRACT FROM AUTHOR]

Aims and objectives. The literature review was conducted to explore those factors which complicate pain management in older people to inform future research, education and nursing practice in this area. Background. Acute pain management in hospitalized older people is complex because of the physiological changes of ageing, pharmacological factors and under-representation of this patient group in reported research about assessing acute pain. Methods. A review of the literature was undertaken using electronic databases and specified search terms, some hand searching was also used and included the grey literature, textbooks and conference proceedings. A computerized literature search was carried out using CINAHL, Bandolier, Cochrane, Medline, the British Nursing Index and the International Association for the Study of Pain website for the period 1992-2004. The search terms were acute pain, older people, elder care, pain assessment and acute pain services. Thirty-seven research-based reviews and published studies and 17 policy documents were included. Conclusions. Managing acute pain well in older adults involves understanding the influence of a series of integrated factors: attitudes and beliefs, physiological ageing processes, pharmacological factors and the social construction of the older person in healthcare contexts. Relevance to clinical practice. This review offers new insight into those factors which, taken together, add complexity to managing acute pain in older people well. Moreover, nurses are the professional group mainly responsible for assessing pain, administering and now prescribing analgesia and evaluating the quality of pain relief in older people. On this basis, they are also the group most likely to effect improved patient outcomes. [ABSTRACT FROM AUTHOR]

Aims. This paper reports on organizational influences on nurse consultant post holders. The influence of individual characteristics has been the subject of another paper. Background. Nurse consultant posts were set up in the United Kingdom from the late 1990s onwards and, therefore, there has been little opportunity to report on evaluations of these innovative initiatives. Design. A cross-sectional design, using a convenience sample, was adopted. Methods. Ten nurse consultants working in a variety of settings and specialties participated in in-depth, tape-recorded interviews. The data were analysed using the Framework approach. Findings. Support systems were important influences on nurse consultants' role achievement levels. These took the form of internal trust networks, nurse consultant forums and links with higher education institutions. Post holders both gave and received support and acted to empower other nurses. Thus, relationships were vital to successful role integration. The culture and structures of the National Health System were also a powerful influence in terms of local and national modernization policies, and participants had to be careful in their choice of strategies to deal with the traditional medically dominated culture. Conclusions. The new nurse consultant role is challenging and innovative, but a major area of contention is how much post holders are expected to take on work previously done by doctors rather than developing their nursing role. Organizational support and commitment are needed if nurse consultants are to maximize the benefits of this innovation. Relevance to clinical practice. The findings show that new nursing roles are not always easily accepted in multidisciplinary settings and that holders of such post need to have the appropriate previous knowledge, skills and personal characteristics, as well as the ability to negotiate their way through organizational influences. [ABSTRACT FROM AUTHOR]

Aim. This paper reports one aspect of a larger study of nursing research strategies in one English region, focusing particularly on nurse consultants' characteristics and achievements in the role. Background. Nurse consultant posts have only been established in the United Kingdom since 1999 and, although much comment has appeared in the professional literature, there is very little research-based evidence of how the roles are developing. The role is intended to integrate four domains: expert practice; professional leadership and consultancy; education, training and development; and practice and service development. Design. A cross-sectional design, using a convenience sample, was adopted. Methods. Ten nurse consultants working in a variety of settings and specialties participated in in-depth, tape-recorded interviews. The data were analysed using the Framework approach. Results. Four themes were identified from the data: characteristics of the postholder, role achievement, support systems and National Health Service influences. The first two themes are discussed in this paper and the data show that the nurse consultants varied in terms of their academic background and previous experience. Not all had the recommended minimum of Master's degree level preparation and some had limited research experience. These background characteristics seemed to influence the degree to which they were able to achieve the four domains of the role, with those with lower qualifications and from a mental health background appearing to struggle most. Conclusions. New appointments to these roles should only be made when candidates possess the recommended levels of educational preparation and professional experience of change management. It is also important that there is clarity about the scope of the role, which should not include management responsibilities. On-going research is essential to evaluate how the roles develop for postholders, the extent to which they fulfil policymakers' expectations and what difference they make to patient care from a patient perspective. Relevance to clinical practice. The findings show that holders of such posts need to have appropriate previous knowledge, skills and personal characteristics, as these seem to influence their ability to integrate the four domains of the role and thus achieve the requirements of the post. [ABSTRACT FROM AUTHOR]

The care of critically ill children has received much attention in the past decade, and many of the recommendations from reports relating to the provision of paediatric intensive care have been addressed. In comparison, high dependency care has received less attention. This level of care is often provided on 'general' children's wards, yet its impact on nursing staff and care delivery have received little attention. This article presents a study which explores nurses' experiences of providing high dependency care on children's wards using focus groups. Following analysis, six categories emerged: definitions and perceptions of high dependency care; having a high dependency unit; problems in district general hospitals; the skills needed for high dependency care; team working; and staffing for high dependency care. These findings have implications for current clinical, managerial and educational practice and for future developments in the field of high dependency care for children. [ABSTRACT FROM AUTHOR]

Reflex sympathetic dystrophy was the presenting feature in an otherwise occult case of non-metastatic squamous cell carcinoma of the lung which improved on surgical removal of the primary tumour. Reflex sympathetic dystrophy, therefore, should be considered an occasional manifestation of a paraneoplastic syndrome warranting a thorough search for underlying malignancy. [ABSTRACT FROM PUBLISHER]

Of seven patients with quinidine-induced polyarthropathy, four had positive antinuclear antibodies and could be considered to have had quinidine-induced lupus erythematosus. The remaining three patients had milder symptoms, which occurred soon after the start of quinidine therapy, and did not have antinuclear antibodies. To confirm the association, the latter three patients were rechallenged with quinidine therapy, which caused recurrence of symptoms within 1 week. Antihistone antibodies, which are characteristic of drug-induced lupus erythematosus associated with procainamide and hydralazine therapy, were detected in all patients with quinidine-induced lupus erythematosus. An unusual characteristic of antihistone antibodies seen in two patients was the presence of high levels of IgG antibodies to histone H1 as well as H2A.H2B and H3.H4 complexes, without antibodies to the individual core histones. [ABSTRACT FROM AUTHOR]

The article focuses on the study conducted by Jonathan Puthoff and colleagues regarding the properties of grip on the soles of gecko's feet. It states that the self-cleaning microscopic spatula-shaped hairs or setae are responsible for the capacity of geckos to cling on smoothest surfaces without fluid adhesives. It mentions that the geckos could be benefited by added adhesion in humid environments through capillary action that was offered by microscopic droplets between the setae and surfaces.

Background: Abnormal foot posture is a common complaint presented in pediatric and pediatric orthopedic clinics. Functional, objective assessment of foot posture, with the potential for early identification of pathologic foot deformities, has, however, been lacking to date. While quantifying functional and regional impulses via dynamic pedobarography can improve the clinical assessment of children's feet, normative values have not yet been reported or characterized., Research Question: The objectives of this study were to: (1) quantify and characterize the pattern and spectrum of foot impulses in walking-aged, typically developing children; and (2) compare these to impulses from non-disabled adults., Methods: Foot impulses of 102 participants (52 female) in five pre-determined age groups (2-3, 4-6, 7-10, 11-14, 15-17 years) were examined using dynamic pedobarography. Each pressure map (3 per foot per child) was divided according to anatomical foot regions: the hallux, heel, medial forefoot, lateral forefoot, lesser toes (D2 to D5), and midfoot. The impulse was calculated for each region and used to generate regional percent impulses and impulse ratios to assess anteroposterior and mediolateral balance within the foot., Results: The impulse through the midfoot was highest in the youngest age group, with a corresponding lower impulse through the medial forefoot. As age advanced, the midfoot impulse decreased (p = 0.001), and the forefoot balance shifted slightly more medially (%Medial Forefoot: p = 0.004; Medial-Lateral Forefoot Balance: p = 0.019). When compared to adults, there were no significant differences between 15-17 year old children and adults in any of the regional percent impulses and impulse ratios. This indicates that skeletal maturity of the foot by late adolescence results in functional characteristics seen in adults., Significance: The age-standardized norms of functional and regional impulse measures in children reported in this study can be used as a comparative benchmark in the clinical assessment of children presenting with various foot deformities., (Copyright © 2020 Elsevier B.V. All rights reserved.)

What is COVID-19's impact on development? What lessons can be drawn from development studies regarding the effects of and recovery from COVID-19? The unprecedented scale and scope of government interventions carry implications at all levels: global, national, and local. In this introduction, our team of Editors underline the importance of systematic substantive study to further knowledge acquisition, and rigorous global-, national-, or context-specific evaluation to inform evidence-based policymaking. The 12 articles summarised here capture these values and sense of "high quality". In particular, despite early considerations in the first year of the pandemic, they illuminate the need for diverse responses beyond business-as-usual, attention to the multiplicity of impact of policies formulated, and progressive strategies to counteract the impacts of this disaster around the world. The path of future research is clear: studies need to consider and give voice to marginalised groups to counteract the short- and long-term impacts of the pandemic., (© Springer Nature Limited part of Springer Nature 2020.)

A case of progressive multifocal leukoencephalopathy (PML) occurring on low dose immunosuppression for systemic lupus erythematosus (SLE) and Sjogren's syndrome (SS) is presented. Neurologic changes in patients with SLE or SS should not be assumed to be a disease manifestation. Importantly, serious opportunistic infections such as PML can occur in minimally immunosuppressed rheumatic patients. Early diagnosis, facilitated by scrutiny of MRI findings, should trigger measures to reconstitute immunity in an otherwise fatal disease., (Copyright © 2019. Published by Elsevier Ltd.)

Background: Dynamic pedobarography is used to measure the change in plantar pressure distribution during gait. Clinical methods of pedobarographic analysis lack, however, a standardized, functional segmentation or require costly motion capture technology and expertise. Furthermore, while commonly used pedobarographic measures are mostly based on peak pressures, progressive foot deformities also depend on the duration the pressure is applied, which can be quantified via impulse measures., Research Question: Our objectives were to: (1) develop a standardized method for functionally segmenting pedobarographic data during gait without the need for motion capture; (2) compute pedobarographic measures that are based on each segment's vertical impulse; and (3) obtain a normative set of such pedobarographic measures for non-disabled gait., Methods: Pedobarographic data was collected during gait from sixty adults with normal feet. Using the maximum pressure map for each trial, an expert and novice rater independently identified the hallux, heel, medial forefoot, and lateral forefoot and computed nine normalized vertical impulse measures., Results: From the computed impulse measures, the Heel-to-Forefoot Balance was 33.3 ± 5.5%, the Medial-Lateral Forefoot Balance (with hallux) 59.2 ± 8.0%, the Medial-Lateral Forefoot Balance (without hallux) 53.5 ± 7.7%, and the Hallux-to-Medial Forefoot Balance 21.0 ± 8.9% (mean ± standard deviation). The intra- and inter-rater reliability ranged between 0.93 and 1.00 and between 0.89 and 0.99, respectively (ICC(2,1))., Significance: We developed a simple, stand-alone method for pedobarographic segmentation that is mechanistically linked to relevant anatomical regions of the foot. The normative impulse measures exhibited excellent reliability. This normative dataset is currently used in the clinical assessment of different foot deformities and gait impairments, and in the evaluation of treatment outcomes., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objectives: Given the involvement of cilia in midline neurodevelopment, we set to determine whether children with midline neuroanatomical defects have increased prevalence of ciliary dysfunction, using nasal nitric oxide measurement, a screening test for primary ciliary dyskinesia., Study Design: We measured the nasal nitric oxide levels of 26 children ages 6-17, with congenital midline central nervous system defects, who are otherwise healthy. We evaluated the effect of variables including: age, gender, and anomaly (brain, spinal cord, or combined) on our measurements. We compared our results with the previously established normal range (153.6-509.9 nL/min) and to the cutoff for children with primary ciliary dyskinesia (77 nL/min)., Results: The overall range for nasal nitric oxide in our cohort was 56.5-334.7 nL/min, with age, gender, and anomaly not having a significant effect. The overall mean, 217.7 nL/min, was significantly lower than the preestablished mean in normal children, 314.51 nL/min (P < 0.01). Four patients (15.4%) had nitric oxide levels below the lower end of normal, with two (7.7%) having values below the cutoff for primary ciliary dyskinesia., Conclusions: This is the first study to report a possible association between ciliary dysfunction and isolated congenital midline neuroanatomical defects, not in the context of any known syndrome. We suggest that genes known to cause isolated central nervous system defects may also be involved in the function of cilia. Longitudinal studies are required to investigate whether, in children with abnormal measurements, nasal nitric oxide levels normalize over time, and whether these children suffer from any respiratory sequelae., (Copyright © 2015 Elsevier Inc. All rights reserved.)

This study provides quantitative data on the extent of gyrencephaly in the large-brained African elephant and several species of cetaceans (from smaller to larger brained) in comparison with other mammals. Across three mammalian orders (primates, carnivores, and artiodactyls), the species with the larger brains are more gyrencephalic with each order, exhibiting a specific negative allometry. The African elephant, with a 5-kg brain, has a gyrencephalic index (GI) of 3.89, which, though highly gyrencephalic, is not more so than would be predicted for a mammal with a 5-kg brain. The cetaceans had an average GI of 5.43, are the most gyrencephalic mammals studied to date, and are more gyrencephalic than one would predict based on comparison with other mammals. No relationship between brain mass and GI was evident in the cetaceans as seen in other mammals, with all cetaceans showing similar GIs irrespective of brain mass (range of GI 5.23-5.70, range of brain mass 577-5617 g). This is yet another parameter indicating cetaceans to be neuroanatomical outliers. Two species of pinnipeds studied had GIs that were well above those seen for terrestrial carnivores, and the aquatic manatee was close to lissencephalic. Thus, all three groups of marine mammals showed unusual extents of cortical gyrencephaly, indicating a morphological alteration of the telencephalon associated with the return to the marine environment. The analysis suggests that cortical thickness and neuronal density are important factors in determining the extent of gyrencephaly across mammalian species., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: Much attention has been given to the effect of pressure on skin blood flow in the feet of older people and people with diabetes. However, little attention has been paid to other areas of the body, especially under the belt at the waist where pressure might be high during body movements associated with exercise. This may be very important when devices such as heat packs are worn during the day under the belt because their safety relies on appropriate skin blood flow to dissipate the heat; in diabetes populations burns have been seen., Methods: Forty male and female subjects, with and without diabetes, were examined in two series of experiments to assess the vertical and shear pressure under a belt worn during different common exercises. Vertical and shear pressure under the belt, belt tension, and shear pressure were measured with a Tactilus (Sensor Products, Madison, NJ) pressure mapping system. Eleven different body movements were examined. Then, from the recorded pressures, a second series of experiments examined skin blood flow at these same pressures., Results: The results of the experiments showed that there was little shear and vertical pressure in thin subjects during 10 different exercises. However, for overweight subjects, pressure under the belt was as high as 150 kPa. At these high levels of pressure, skin circulation was occluded., Conclusions: In subjects with diabetes who are generally overweight and have impaired circulation, hot packs should be used with caution because of the low blood flows at rest and occlusion of the circulation under the belt with body movement.

Background: To protect against ischemia, pressure-induced vasodilation (PIV) causes an increase in skin blood flow. Endothelial dysfunction, which is commonly found in older patients and those with diabetes, and global temperatures can affect the resting blood flow in skin, which may reduce the blood flow during and after the application of local pressure. The present study investigated the PIV of the skin with exposure to three global temperatures in younger and older populations and those with diabetes., Materials and Methods: Older subjects (n = 15, mean age 64.2 +/- 14.0 years), subjects with diabetes (n = 15, mean age 62 +/- 5.9 years, mean duration 13.2 +/- 9.1 years), or younger subjects (n = 15, mean age 25.7 +/- 2.9 years) participated. An infrared laser Dopler flow meter was used to measure skin blood flow on the bottom of the foot, lower back, and hand during and after applications of pressure at 7.5, 15, 30, 45, and 60 kPa at 16 degrees C, 24 degrees C, and 32 degrees C global temperatures., Results: The resting blood flow for all subjects was significantly lower in the 16 degrees C environment (P < 0.05). Blood flow in the group with diabetes was significantly lower at rest, during the application of all pressure, and after the release of pressure in all global temperatures (P < 0.05). The younger group showed a significant increase in blood flow after every pressure application, except 7.5 kPa, in all global conditions (P < 0.001). Older subjects and patients with diabetes did not have a significant reactive hyperemia, especially in the 16 degrees C environment., Conclusion: The protective mechanism of PIV is severely reduced in older populations and those with diabetes, especially in colder environments where skin blood flow is already diminished.

Numerous studies have examined the effect of local and global heating of the body on skin blood flow. However, the effect of the moisture content of the heat source on the skin blood flow response has not been examined. Thirty-three subjects, without diabetes or cardiovascular disease, between the ages of 22 and 32 were examined to determine the relationship between the effects of dry vs. moist heat applied for the same length of time and with the skin clamped at the same skin temperature on the blood flow response of the skin. The skin, heated with an infrared heat lamp (skin temperature monitored with a thermocouple) to 40 degrees C for 15 min, was either kept moist with wet towels or, in a separate experiment, kept dry with Drierite (a desiccant) between the towels to remove any moisture. Before and after heat exposure of the forearm, blood pressure, heart rate, skin moisture content, skin temperature, and skin blood flow were recorded. The results of the experiment showed that there was no change in skin moisture after 15 min exposure to dry heat at 40 degrees C. However, with moist heat, skin moisture increased by 43.7%, a significant increase (P < 0.05). With dry heat, blood flow increased from the resting value by 282.3% whereas with moist heat, blood flow increased by 386% over rest, a significant increase over dry heat (P < 0.05). Thus, with a set increase in skin temperature, moist heat was a better heating modality than dry heat. The reason may be linked to moisture sensitivity in calcium channels in the vascular endothelial cell.

Background: Previous data has shown that when pressure is applied to the skin of the ankle and on the foot, there is a reactive increase in circulation. In the present investigation, these studies were expanded to look at the response of the hand, back, and foot to applied pressure., Material/methods: Ten young subjects whose average age was 26.5+/-3.3 yrs, 10 older subjects whose average age was 73.3+/-19.7 yrs and 10 people with diabetes whose average age was 60.1+/-5.7 yrs participated in the study. There was no statistical difference in the height or weight of the subjects. Hemoglobin A1c of the group with Diabetes averaged 6.98+/-1.15% with the mean duration of diabetes 13.6+/-9.5 yrs. An infrared laser Doppler flow meter was used to measure circulation on the hand, lower back, and on the bottom of the foot during applications of pressure at 15, 30, 45, and 60 kPa., Results: For all three areas of the body, circulation was significantly less in the group with diabetes than the other two groups (p<0.05). When pressure was applied at 15 kPa, the blood flow to the skin initially decreased, but then increased in the younger subjects and in the older subjects but did not increase in subjects with diabetes for any area of the body. Further, after pressure was released, for any of the four pressures examined here, while the younger subjects showed a pronounced reactive hyperemia, subjects with diabetes showed a diminished hyperemia not proportional to the pressure that was applied., Conclusions: It appears that the normal protective mechanism of a pressure induced hyperemia is absent or diminished in patients with diabetes with more effect on the periphery than on the core area of the body. More importantly, after pressure was applied and released, subjects with diabetes lacked a proportional hyperemia to recovery form the transient ischemia of the pressure.

Background: Vascular endothelial and autonomic damage are hallmarks of type 1 and type 2 diabetes. However, while much has been published on impairment of the autonomic nervous system, much less has been published on the interrelationship between autonomic damage and exercise., Study Design: The present investigation examined the change in heart rate, blood pressure, skin and limb blood flow, and sweat during non-fatiguing (10% and 25% maximum strength [maximal voluntary contraction (MVC)]) and a fatiguing isometric contraction (40% MVC) in people with type 2 diabetes compared to younger and older controls to see if a simple handgrip test could show the extent of autonomic damage in people with diabetes. Fifteen younger subjects (30.6 +/- 8.6 years), 15 older subjects (65.8 +/- 8.8 years), and 15 subjects with diabetes (63.4 +/- 14.4 years) whose average percentage body fat was 40.1 +/- 12.9%, 36.1 +/- 9.3%, and 39.6 +/- 15.5%, respectively, participated in these studies. Whole forearm blood flow, skin blood flow, and sweat on the forearm, chest, and forehead were measured at rest and during and after a contraction at 10% MVC, 25% MVC, and 40% MVC., Results: Blood flows and sweat rates were greatest in younger subjects, significantly less in older subjects, and even significantly less in subjects with diabetes (P < 0.05). The heart rate response was unaltered during contractions at 10% and 25% MVC and less in diabetes than in the other two groups with 40% MVC. Strength was about half in the diabetes group than with the other two groups, but endurance was similar., Conclusions: Diabetes is associated with a reduction in handgrip strength and significantly impaired autonomic function during and after isometric exercise.

Background: Ageing reduces the resting blood flow to the skin as well as the blood flow response to thermal stimuli. However, the interrelationships between skin thickness, subcutaneous fat, and skin blood flow in determining the heat dissipation characteristics of the skin have not been investigated., Material/methods: In the present investigation, 60 male and female subjects were examined with either a continuous 0.15 watt heat source or a 40 degrees C instantaneous heat source applied to the skin. Data was correlated to skin and subcutaneous fat thickness measured by ultrasound and to skin blood flow measured by a laser Doppler flow meter., Results: The results of the experiments showed a significant negative correlation between age and skin thickness (p<0.0001) and between age and subcutaneous fat thickness (p<0.001). Blood flows in the skin, with the subject in a 24 degrees C, room were 61.8% less in the older subjects compared to the younger subjects. This was due to both a reduction in red cell concentration and red cell velocity. The lower concentration of red cells matches the reduction in skin thickness, implying a loss in the dermal layer of the skin associated with ageing. The skin blood flow response to continuous heat and to a single heat exposure were both reduced in the older subjects (p<0.01). Ageing also caused a slower response of the skin to heat stress., Conclusions: The results support a reduction in both the resting and post local heat skin blood flows associated with ageing. Some of this may be due to a reduction in dermal layer thickness due to ageing.

The Pennes model predicts the ability of the skin to dissipate heat as a function of conductive heat transfer and blood flow. Conductive heat exchange may be affected by skin moisture and subcutaneous fat thickness, factors not considered by Pennes. In the present investigation, we sought to expand the Pennes model by examining subcutaneous fat and skin moisture as factors of heat dissipation and their effects on heat exchange and blood flow. Subjects who were older (O) (mean age 64.2+/-5.9 years, n=15), had diabetes (D) (mean age 62+/-5.9 years, mean duration 13.2+/-9.1 years, n=15), and were younger (Y) (mean age 25.7+/-2.9 years, n=15) participated. Thermisters were placed in an iron heat probe and on the skin to measure the change in skin temperature to create a thermal change index to demonstrate the ability of the skin to dissipate heat. The lower back had the thickest subcutaneous fat layer for all subjects, which contributed to higher skin temperatures than the foot and hand in response to local and global heat. There was a significant inverse correlation between skin moisture and skin temperature after 5s of heat application (r=-0.73, p<0.001) with O and D having significantly less skin moisture than Y (p<0.05). O and D had significantly increased skin temperatures in response to local heat, as compared to Y, in all global temperatures (p<0.05). Thus, the Pennes model may need to be adjusted to take into consideration aging, diabetes, skin moisture, and subcutaneous fat thickness.

Background: The present study examined the effects of local heat, global heat, and the interaction between these two endothelial stressors on the blood flow of the skin of the foot in people who are older and who have diabetes., Methods: Subjects who were older (mean age 64.2 +/- 5.9 years) and were younger (mean age 25.7 +/- 2.9 years) and subjects who had diabetes (mean age 62 +/- 5.9 years, mean duration 13.2 +/- 9.1 years) participated. Subjects were exposed to three global temperatures (16 degrees C, 24 degrees C, and 32 degrees C), and the blood flow response was recorded on the foot with a laser Doppler flow meter for 30 s following applications of local heat (30 degrees C, 33.5 degrees C, and 37 degrees C) using a Peltier junction to clamp the skin for 2 min., Results: All three groups significantly increased blood flow from the 16-24 degrees C environments for the 37 degrees C application of local heat (P(Younger) = 0.02, P(Older) = 0.02, P(Diabetes) = 0.01). Those with diabetes and those who were older only increased blood flow 5% and 6% from the 24-32 degrees C environment, which was not statistically significant (P(Older) = 0.12, P(Diabetes) = 0.14)., Conclusions: There appears to be considerable blood flow reserve in younger subjects to tolerate heat stress. In contrast, older subjects and those with diabetes reach a critical level after which additional heat does not cause in increase in blood flow.