Thermal protection of the new born during carrying: an evaluation of parents’ practices [Abstract]

Public health guidelines on how to ensure babies’ thermal protection are available (e.g. dressing with 1 extra layer of clothing than the adult); yet little is known on the strategies that parents adopt to ensure their babies’ thermal protection when these are carried in a sling (i.e. babywearing). The aim of this study was to survey parents’ practices during babywearing with regards to baby dressing and thermal monitoring in the heat and cold

Neurophysiology of skin thermal sensations

Undoubtedly, adjusting our thermoregulatory behavior represents the most effective mechanism to maintain thermal homeostasis and ensure survival in the diverse thermal environments that we face on this planet. Remarkably, our thermal behavior is entirely dependent on the ability to detect variations in our internal (i.e., body) and external environment, via sensing changes in skin temperature and wetness. In the past 30 years, we have seen a significant expansion of our understanding of the molecular, neuroanatomical, and neurophysiological mechanisms that allow humans to sense temperature and humidity. The discovery of temperature-activated ion channels which gate the generation of action potentials in thermosensitive neurons, along with the characterization of the spino-thalamo-cortical thermosensory pathway, and the development of neural models for the perception of skin wetness, are only some of the recent advances which have provided incredible insights on how biophysical changes in skin temperature and wetness are transduced into those neural signals which constitute the physiological substrate of skin thermal and wetness sensations. Understanding how afferent thermal inputs are integrated and how these contribute to behavioral and autonomic thermoregulatory responses under normal brain function is critical to determine how these mechanisms are disrupted in those neurological conditions, which see the concurrent presence of afferent thermosensory abnormalities and efferent thermoregulatory dysfunctions. Furthermore, advancing the knowledge on skin thermal and wetness sensations is crucial to support the development of neuroprosthetics. In light of the aforementioned text, this review will focus on the peripheral and central neurophysiological mechanisms underpinning skin thermal and wetness sensations in humans

Psychosocial factors and their significance towards pain: a case study comparing monozygotic twins with AIS after spinal surgery

INTRODUCTION: Adolescent Idiopathic Scoliosis (AIS) is one of the most common spinal abnormalities in children, affecting 2% to 3% of adolescents in the United States. Its cause remains unclear. Many previous studies conclude that AIS may be caused by a combination of genetic and environmental factors, with very few consistencies. Severe scoliosis is usually treated with corrective surgery, and the etiology of post-surgical pain is even more unclear and has the opportunity to affect the patient well into adulthood. STUDY AIMS: By following a monozygotic twin pair with identical DNA, our retrospective case study can control for genetic disposition, and can look toward other possible causes for the pain the patients experienced. This study attempts to shed light on the complexities of AIS and pain with a focus on environmental and psychosocial factors. CASE PRESENTATION: We present a single pair of monozygotic twins treated for AIS with comparable spinal fusion surgeries performed at a large northeast urban children's hospital. Twin A and Twin B were initially treated with a brace for their scoliosis. Despite bracing, their curves progressed and warranted spinal fusion, with Twin A having a Cobb angle of 53°, and Twin B with 50°. The surgery was conducted simultaneously at the age of 13 by two different orthopedic surgeons. At age 7.5, Twin B was treated for Ebstein's anomaly of the tricuspid valve and significant dysrhythmias. METHODS: After the patients were discharged, a comprehensive retrospective chart review of the patients' pre-op, inpatient, and post-op pain and drug regiment was conducted. The patients were also asked to note their pain as they recovered after discharge. The patients and their mother completed self-report measures of multiple psychosocial variables both before and after surgery through REDCap. A Quantitative Sensory Test (QST) was also performed by the patients to assess their sensory sensitivity and pain thresholds. Mechanical, pressure, and thermal scores were obtained with the use of von Frey hairs, a pressure Algometer, and a Thermode. The QST was administered on the patients' palm/ thenar eminence (distant non-surgical site), and on their lower back (surgical site). The QST results were compared to a previous study's median cohort data, to discern if the patients presented hyper- or hyposensitivity for that particular test. RESULTS: Due to the limitations of case studies, the results presented here should be considered strictly preliminary. Twin B experienced more significant pain during both the acute and chronic recovery phases after surgery, and showed lower sensitivities during most pre-op QST trials. Twin B also scored markedly higher on a number of sub-variables in the psychosocial surveys. A notable correlation was the parent protective measure, indicating that the mother may have been more protective of Twin B. CONCLUSIONS: What is unique to this study is that age, gender, Cobb angle, fusion length, and genetic disposition are all controlled for, allowing us to analyze the patients based on other risk factors. Twin B shows consistently higher pain scores while in the hospital as well as while recovering at home. The parent self-report measures support these findings, showing a slight bias in favor of Twin B in regards to protectiveness, which also coincides with large-scale studies. Although preliminary, it is important not to underestimate the role environmental and psychosocial factors play in post-surgical pain

Why wet feels wet? An investigation into the neurophysiology of human skin wetness perception

The ability to sense humidity and wetness is an important sensory attribute for many species across the animal kingdom, including humans. Although this sensory ability plays an important role in many human physiological and behavioural functions, as humans largest sensory organ i.e. the skin seems not to be provided with specific receptors for the sensation of wetness (i.e. hygroreceptors), the neurophysiological mechanisms underlying this complex sensory experience are still poorly understood. The aim of this Thesis was to investigate the neurophysiological mechanisms underpinning humans remarkable ability to sense skin wetness despite the lack of specific skin hygroreceptors. It was hypothesised that humans could learn to perceive the wetness experienced when the skin is in contact with a wet surface or when sweat is produced through a complex multisensory integration of thermal (i.e. heat transfer) and tactile (i.e. mechanical pressure and friction) inputs generated by the interaction between skin, moisture and (if donned) clothing. Hence, as both thermal and tactile skin afferents could contribute significantly to drive the perception of skin wetness, their role in the peripheral and central sensory integration of skin wetness perception was investigated, both under conditions of skin s contact with an external (dry or wet) stimulus as well as during the active production of sweat. A series of experimental studies were performed, aiming to isolate the contribution of each sensory cue (i.e. thermal and tactile) to the perception of skin wetness during rest and exercise, as well as under different environmental conditions. It was found that it is not the contact of the skin with moisture per se, but rather the integration of particular sensory inputs which drives the perception of skin wetness during both the contact with an external (dry or wet) surface, as well as during the active production of sweat. The role of thermal (cold) afferents appears to be of a primary importance in driving the perception of skin wetness during the contact with an external stimulus. However, when thermal cues (e.g. evaporative cooling) are limited, individuals seem to rely more on tactile cues (i.e. stickiness and skin friction) to characterise their perception of skin wetness. The central integration of conscious coldness and mechanosensation, as sub-served by peripheral cutaneous A-nerve fibers, seems therefore the primary neural process underpinning humans ability to sense wetness. Interestingly, these mechanisms (i.e. integration of thermal and tactile sensory cues) appear to be remarkably consistent regardless of the modality for which skin wetness is experienced, i.e. whether due to passive contact with a wet stimulus or due to active production of sweat. The novelty of the findings included in this Thesis is that, for the first time, mechanistic evidence has been provided for the neurophysiological processes which underpin humans ability to sense wetness on their skin. Based on these findings, the first neurophysiological sensory model for human skin wetness perception has been developed. This model helps explain humans remarkable ability to sense warm, neutral and cold skin wetness

Radiofrequencies and Proctology: A Difficult Marriage

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Slips, trips and falls in crowds

Crowd situations are commonplace and involve circumstances known to lead to slips, trips and falls (STF). Data from focus groups with crowd participants (5 groups, n = 35 individuals); observations of crowd situations (n = 55); and interviews with crowd organisers (n = 41) were analysed to examine understanding of and responses to the risk of STF in crowds. Although safety was a high priority for both crowd participants and organisers, explicit consideration of STF as a safety concern was low among both groups. Crowd observations found STF risks mitigated on some occasions and present on others, without any discernible pattern for the variation. A risk management framework for STF risk in crowds is proposed. It is concluded that improved understanding is needed of the nature and pattern of STF occurrence in crowds and the efficacy of measures for prevention.N/

A case report on the physiological responses to extreme heat during Sicily's July 2023 heatwave

July 2023 has been confirmed as Earth's hottest month on record, and it was characterized by extraordinary heatwaves across southern Europe. Field data collected under real heatwave periods could add important evidence to understand human adaptability to extreme heat. However, field studies on human physiological responses to heatwave periods remain limited. We performed field thermo-physiological measurements in a healthy 37-years male undergoing resting and physical activity in an outdoor environment in the capital of Sicily, Palermo, during (July 21; highest level of local heat-health alert) and following (August 10; lowest level of local heat-health alert) the peak of Sicily's July 2023 heatwave. Results indicated that ~40 min of outdoor walking and light running in 33.8°C Wet Bulb Globe Temperature (WBGT) conditions (July 21) resulted in significant physiological stress (i.e., peak heart rate: 209 bpm; core temperature: 39.13°C; mean skin temperature: 37.2°C; whole-body sweat losses: 1.7 kg). Importantly, significant physiological stress was also observed during less severe heat conditions (August 10; WBGT: 29.1°C; peak heart rate: 190 bpm; core temperature: 38.48°C; whole-body sweat losses: 2 kg). These observations highlight the physiological strain that current heatwave conditions pose on healthy young individuals. This ecologically-valid empirical evidence could inform more accurate heat-health planning

Human skin wetness perception: psychophysical and neurophysiological bases

The ability to perceive thermal changes in the surrounding environment is critical for survival. However, sensing temperature is not the only factor among the cutaneous sensations to contribute to thermoregulatory responses in humans. Sensing skin wetness (i.e. hygrosensation) is also critical both for behavioral and autonomic adaptations. Although much has been done to define the biophysical role of skin wetness in contributing to thermal homeostasis, little is known on the neurophysiological mechanisms underpinning the ability to sense skin wetness. Humans are not provided with skin humidity receptors (i.e., hygroreceptors) and psychophysical studies have identified potential sensory cues (i.e. thermal and mechanosensory) which could contribute to sensing wetness. Recently, a neurophysiological model of human wetness sensitivity has been developed. In helping clarifying the peripheral and central neural mechanisms involved in sensing skin wetness, this model has provided evidence for the existence of a specific human hygrosensation strategy, which is underpinned by perceptual learning via sensory experience. Remarkably, this strategy seems to be shared by other hygroreceptor-lacking animals. However, questions remain on whether these sensory mechanisms are underpinned by specific neuromolecular pathways in humans. Although the first study on human wetness perception dates back to more than 100 years, it is surprising that the neurophysiological bases of such an important sensory feature have only recently started to be unveiled. Hence, to provide an overview of the current knowledge on human hygrosensation, along with potential directions for future research, this review will examine the psychophysical and neurophysiological bases of human skin wetness perception

Independent and interactive effects of thermal stress and mental fatigue on manual dexterity

Many occupations and sports require high levels of manual dexterity under thermal stress and mental fatigue. Yet, multistressor studies remain scarce. We quantified the interactive effects of thermal stress and mental fatigue on manual dexterity. Seven males (21.1 \ub1 1.3 yr) underwent six separate 60-min trials characterized by a combination of three air temperatures (hot, 37C; neutral, 21C; cold, 7C) and two mental fatigue states (MF, mental fatigue induced by a 35-min cognitive battery; no-MF, no mental fatigue). Participants performed complex (O'Connor test) and simple (hand-tool test) manual tasks pre- and posttrial to determine stressor-induced performance changes. We monitored participants' rectal temperature and hand skin temperature (Thand) continuously and assessed the reaction time (handclick test) and subjective mental fatigue (5-point scale). Thermal stress (P < 0.0001), but not mental fatigue (P = 0.290), modulated Thand (heat, +3.3C [95% CI: +0.2, +6.5]; cold, 7.5C [10.7, 4.4]). Mental fatigue (P = 0.021), but not thermal stress (P = 0.646), slowed the reaction time (10%) and increased subjective fatigue. Thermal stress and mental fatigue had an interactive effect on the complex manual task (P = 0.040), with cold-no-MF decreasing the performance by 22% [39, 5], whereas neutral-MF, cold-MF, and heat-MF by 36% [53, 19], 34% [52, 17], and 36% [53, 19], respectively. Only mental fatigue decreased the performance in the simple manual task (30% [43, 16] across all thermal conditions; P = 0.002). Cold stress-induced impairments in complex manipulation increase with mental fatigue; yet combined stressors' effects are no greater than those of mental fatigue alone, which also impairs simple manipulation. Mental fatigue poses a greater challenge to manual dexterity than thermal stress