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The crystalline composition of Portland cement clinker is commonly established by Bogue's equations, which are based on a series of assumptions that seldom apply to oilwell cements. This is probably due to the presence of additional oxides and phase reconversion upon cooling of the clinker from the calcination temperature. Important differences are therefore observed between the numerical values yielded by the mathematical equations and image analysis quantification. In this study, the concentration of crystalline phases in oilwell cement was determined using Taylor's procedure, which consists in a system of linear equations corresponding to each one of the four main clinker phases. The results revealed an adequate relationship between this method and phase quantification by optical micrography, especially concerning the contents of aluminate and ferrite.A composição cristalina das fases do clínquer de cimento Portland é comumente avaliada pelas equações de Bogue, que se baseiam em alguns princípios que podem ser aplicados aos cimentos para cimentação de poços de petróleo. Isto se deve provavelmente à presença de diversos óxidos e reconversões de fase durante o resfriamento do clínquer levado à altas temperaturas. Entretanto, diferenças importantes são observadas entre os valores numéricos obtidos nas equações e a quantificação de fases por imagem. Neste estudo, a quantidade das fases cristalinas do clínquer de um cimento especial para poço de petróleo foi determinada empregando o procedimento de Taylor, que consiste na resolução de um sistema de equações lineares correspondente a cada uma das quatro principais fases do clínquer. Os resultados revelam uma adequada inter-relação entre este método e a quantificação das fases por microscopia ótica, principalmente no que se refere à determinação dos teores de alumínio e ferro.

Pyoderma gangrenosum (PG) is a rare, chronic, ulcerative disease characterized by non-healing wounds that worsen with debridement, a phenomenon called pathergy. No consensus regarding pathogenesis, diagnosis, or treatment exists for PG. A previous pilot study using dehydrated human amniotic/chorionic membrane (dHACM), following excisional debridement, augmented PG wound healing and allowed for subsequent wound closure through split-thickness skin grafting (STSG). In this clinical trial (NCT05120726), four patients with an established PG diagnosis were enrolled to undergo treatment with dHACM and characterize the pre- and post-treatment transcriptome profiles. RNA sequencing was used to isolate the total RNA from specimens. Genes of particular interest were quantified through real-time quantitative reverse transcription polymerase chain reaction. We observed varied changes to the local expression of inflammatory response, positive regulators of cellular proliferation, and extracellular matrix disassembly cytokines. All PG wounds produced granulation tissue following treatment and were closed using split-thickness skin grafts., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: The corresponding author serves as a paid consultant for Aroa Biosurgery and is on the advisory board for Prytime Medical. Otherwise, the authors have no relevant conflicts of interest to disclose.

Background and Aims: The experience of outpatient care may differ for select patient groups. This prospective study evaluates the adult patient experience of multidisciplinary outpatient cystic fibrosis (CF) care with videoconferencing through telehealth compared with face-to-face care the year prior., Methods: People with CF without a lung transplant were recruited. Patient-reported outcomes were obtained at commencement and 12 months into the study, reflecting both their face-to-face and telehealth through videoconferencing experience, respectively. Three patient cohorts were analysed: (i) participants with a regional residence, (ii) participants with a nonregional including metropolitan residence and (iii) participants with colonised multiresistant microbiota., Results: Seventy-four patients were enrolled in the study (mean age, 37 ± 11 years; 50% male; mean forced expiratory volume in the first second of expiration, 60% [standard deviation, 23]) between February 2020 and May 2021. No differences between models were observed in the participants' rating of the health care team, general and mental health rating, and their confidence in handling treatment plans at home. No between-group differences in the Cystic Fibrosis Questionnaire - Revised (CFQ-R) were observed. Travel duration and the cost of attending a clinic was significantly reduced, particularly for the regional group (4 h, AU$108 per clinic; P < 0.05). A total of 93% respondents preferred to continue with a hybrid approach., Conclusion: In this pilot study, participants' experience of care and quality of life were no different with face-to-face and virtual care between the groups. Time and cost-savings, particularly for patients living in regional areas, were observed. Most participants preferred to continue with a hybrid model for outpatient care., (© 2023 Royal Australasian College of Physicians.)

The article analyzes the correlation between Bogue's equations and Taylor's procedure for establishing the crystalline composition of Portland cement clinker. The authors explain that the evaluation of crystalline phases in Portland oilwell cement clinker is usually created using Bogue's equations which employ assumptions that rarely apply to oilwell cements. It also emphasizes that using Taylor's procedure, a sufficient connection between the method and phase quantification is observed.

Background: Pelvic fractures cause significant morbidity in the trauma population. Many factors influence time to fracture fixation. No previous study has determined the optimal time window for pelvic fixation., Methods: A retrospective review of trauma patients with pelvic fractures from 2016 to 2020 was performed. Patients were stratified into EARLY and LATE groups, by time to fixation within 3 days or greater than 3 days whether from admission or from completion of a life-saving procedure. Unpaired Student's t -test and Fisher's exact test were performed with multiple linear regression for variables with P < .2 on univariate analysis., Results: 287 patients were identified with a median fixation time of 3 days. There was no significant difference in demographics, incidence of preceding life-saving procedure, angioembolization, or mechanism of injury in the 2 groups ( P > .05). Length of stay in the EARLY group was significantly reduced at 11.9 +/- .7 days compared to 18.0 +/-1.2 days in the LATE group ( P < .001). There was no significant difference in rates of ventilator-associated pneumonia, deep vein thrombosis, pulmonary embolism (PE), acute kidney injury (AKI), pressure ulcer, or acute respiratory distress syndrome (ARDS) ( P > .05). There were significantly more SSIs (surgical site infections) in the LATE group. After multiple linear regression adjusting for covariates of age and ISS, the difference in hospital LOS was 5.5 days (95% CI -8.0 to -3.1, P < .001)., Discussion: Fixation of traumatic pelvic fractures within 3 days reduced LOS. Prospective multi-center studies will help identify additional factors to decrease time to surgery and improve patient outcomes.

Spirometry is usually performed under the supervision of a trained respiratory scientist to ensure acceptability and repeatability of results. To evaluate the quality of spirometry performance by adult cystic fibrosis (CF) patients with and without observation by a trained respiratory scientist, an observational, single centre study was conducted between February to December 2020. 74 adults were recruited and instructed to perform spirometry without supervision within 24 h of their remote CF clinic consultation. Spirometry was repeated at their consultation, supervised by a respiratory scientist using video conferencing. The majority of patients achieved grade A (excellent) or B (very good) spirometry quality with (95%) and without supervision (93%) independent of lung function severity. Similarly, forced expiratory volume in 1 second demonstrated no significant differences with paired spirometry performed within a 24 hour period. For a large proportion of adult CF patients, unsupervised portable spirometry produces acceptable and repeatable results., Competing Interests: Declaration of Competing Interest There are no conflicts of interests for all authors in regards to this study., (Copyright © 2021. Published by Elsevier B.V.)

Arthritis is a chronic condition that affects nearly a quarter of the United States population. Osteoarthritis (OA) and rheumatoid arthritis (RA) are two major forms of arthritis associated with severe joint pain and reduced quality of life. Various pharmacological interventions may be utilized for arthritis treatment when non-pharmacological therapy is insufficient. However, pharmacological therapy can be associated with serious side effects and high costs. Therefore, alternative therapies have been under investigation. Herbal medications have shown the potential for safe and effective management of arthritis. For this review, we attempt to summarize the mechanisms, safety, and efficacy of herbal treatments for OA and RA. After searching electronic databases, we identified nine herbs among 23 clinical trials used for the treatment of OA or RA patients. Improvement of OA and RA symptoms, pain, and inflammation was demonstrated. The herbs exhibited strong anti-inflammatory and anti-oxidant activities, contributing to a reduction in inflammation and tissue damage. Several herbs elucidated new mechanisms for OA and RA treatment as well. Though these herbs have shown promise for OA and RA treatment, more studies and clinical trials are required for determining safety and efficacy, bioactivity, and optimal bioavailability.

Public Natural Resource Management (NRM) agencies operate in complex social-ecological domains. These complexities proliferate unpredictably therefore investigating and supporting the ability of public agencies to respond effectively is increasingly important. However, understanding how public NRM agencies innovate and restructure to negotiate the range of particular complexities they face is an under researched field. One particular conceptualisation of the social-ecological complexities facing NRM agencies that is of growing influence is the Water-Energy-Food (WEF) nexus. Yet, as a tool to frame and understand those complexities it has limitations. Specifically, it overlooks how NRMs respond institutionally to these social-ecological complexities in the context of economic and organisational challenges-thus creating a gap in the literature. Current debates in public administration can be brought to bear here. Using an organisational cultures approach, this paper reports on a case study with a national NRM agency to investigate how they are attempting to transform institutionally to respond to complexity in challenging times. The research involved 12 elite interviews with senior leaders from Natural Resources Wales, (NRW) and investigated how cultural narratives are being explicitly and implicitly constructed and mobilised to this end. The research identified four distinct and sequential cultural narratives: collaboration, communication, trust, and empowerment where each narrative supported the delivery of different dimensions of NRW's social-ecological complexity mandate. Counter to the current managerialist approaches in public administration, these results suggest that the empowerment of expert bureaucrats is important in responding effectively to complexity.

Cutaneous squamous cell carcinoma (cSCC) causes approximately 10,000 deaths annually in the U. S. Current therapies are largely ineffective against metastatic and locally advanced cSCC. There is a need to identify novel, effective, and less toxic small molecule cSCC therapeutics. We developed a 3-dimensional bioprinted skin (3DBPS) model of cSCC tumors together with a microscopy assay to test chemotherapeutic effects in tissue. The full thickness SCC tissue model was validated using hematoxylin and eosin (H&E) and immunohistochemical histological staining, confocal microscopy, and cDNA microarray analysis. A nondestructive, 3D fluorescence confocal imaging assay with tdTomato-labeled A431 SCC and ZsGreen-labeled keratinocytes was developed to test efficacy and general toxicity of chemotherapeutics. Fluorescence-derived imaging biomarkers indicated that 50% of cancer cells were killed in the tissue after 1μM 5-Fluorouracil 48-hour treatment, compared to a baseline of 12% for untreated controls. The imaging biomarkers also showed that normal keratinocytes were less affected by treatment (11% killed) than the untreated tissue, which had no significant killing effect. Data showed that 5-Fluorouracil selectively killed cSCC cells more than keratinocytes. Our 3DBPS assay platform provides cellular-level measurement of cell viability and can be adapted to achieve nondestructive high-throughput screening (HTS) in bio-fabricated tissues., Competing Interests: CONFLICTS OF INTEREST The authors state no conflicts of interest., (Copyright: © 2020 Browning et al.)

Introduction: The American Diabetes Association recommends annual screenings for prediabetes if the patient meets the suggested requirements. The overall prevalence of prediabetes has decreased from an estimated 86 million adults in 2012 to 84.1 million adults in 2015 in the United States. Along with lifestyle modifications, the use of metformin as a treatment option or in combination has shown a decrease in weight and health care costs. This study was designed to review the prevalence of screening and treatment of prediabetes in the United States by using the National Ambulatory Medical Care Survey, as well as identify any factors associated with screenings and treatment., Methods: The National Ambulatory Medical Care Survey was used to examine a study sample of office visits between 2012 and 2015, reviewing the prevalence of screenings and lab services ordered or provided at each patient visit. Inclusion criteria consisted of the recommendations given by the American Diabetes Association including any patient ≥45 years or adult patient <45 years with a body mass index of ≥25 kg/m 2 and an additional risk factor. Patients with a previous diagnosis of diabetes were excluded from the sample., Results: A total of 105,721 office visits (2012 to 2015) were included in the analysis. The diabetes screening prevalence increased from 10% in 2012 to 13.4% in 2015. Metformin (n = 140, 76.1%) was the most common antidiabetic medication prescribed to treat prediabetes., Conclusions: The prevalence of diabetes screening during office visits remained lower than 15% between 2012 and 2015 in the United States. Physicians primarily prescribe lifestyle modifications, including a healthy diet and exercise, with metformin being used in some cases for the prevention of diabetes., Competing Interests: Conflict of interest: none declared., (© Copyright 2019 by the American Board of Family Medicine.)

Claudin-low breast cancer is an aggressive subtype that confers poor prognosis and is found largely within the clinical triple-negative group of breast cancer patients. Here, we have shown that intrinsic and immune cell gene signatures distinguish the claudin-low subtype clinically as well as in mouse models of other breast cancer subtypes. Despite adaptive immune cell infiltration in claudin-low tumors, treatment with immune checkpoint inhibitory antibodies against cytotoxic T lymphocyte-associated protein 4 (CTLA-4) and programmed death receptor 1 (PD-1) were ineffective in controlling tumor growth. CD4+FoxP3+ Tregs represented a large proportion of the tumor-infiltrating lymphocytes (TILs) in claudin-low tumors, and Tregs isolated from tumor-bearing mice were able to suppress effector T cell responses. Tregs in the tumor microenvironment highly expressed PD-1 and were recruited partly through tumor generation of the chemokine CXCL12. Antitumor efficacy required stringent Treg depletion combined with checkpoint inhibition; delays in tumor growth were not observed using therapies that modestly diminished the number of Tregs in the tumor microenvironment. This study provides evidence that the recruitment of Tregs to the tumor microenvironment inhibits an effective antitumor immune response and highlights early Treg recruitment as a possible mechanism for the lack of response to immune checkpoint blockade antibodies in specific subtypes of cancer that are heavily infiltrated with adaptive immune cells.

In this experiment, hand and forearm vasomotor activity was investigated during localised, but stable heating and cooling of the face, hand and thigh, under open-loop (clamped) conditions. It was hypothesised that facial stimulation would provoke the most potent vascular changes. Nine individuals participated in two normothermic trials (mean body temperature clamp: 36.6°C; water-perfused suit and climate chamber) and two mildly hyperthermic trials (37.9°C). Localised heating (+5°C) and cooling (-5°C) stimuli were applied to equal surface areas of the face, hand and thigh (perfusion patches: 15min), while contralateral forearm or hand blood flows (venous-occlusion plethysmography) were measured (separate trials). Thermal sensation and discomfort votes were recorded before and during each thermal stimulation. When hyperthermic, local heating induced more sensitive vascular responses, with the combined thermosensitivity of both limb segments averaging 0.011mL·100mL -1 ·min -1 ·mmHg -1 ·°C -1 , and 0.005mL·100mL -1 ·min -1 ·mmHg -1 ·°C -1 during localised cooling (P<0.05). Inter-site comparisons among the stimulated sites yielded minimal evidence of variations in local thermal sensation, and no differences were observed for vascular conductance (P>0.05). Therefore, regional differences in vasomotor and sensory sensitivity appeared not to exist. When combined with previous observations of sudomotor sensitivity, it seems that, during mild heating and cooling, regional representations within the somatosensory cortex may not translate into meaningful differences in thermal sensation or the central integration of thermoafferent signals. It was concluded that inter-site variations in the cutaneous thermosensitivity of these thermolytic effectors have minimal physiological significance over the ranges investigated thus far., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Human eccrine sweat-gland recruitment and secretion rates were investigated from the glabrous (volar) and non-glabrous hand surfaces during psychogenic (mental arithmetic) and thermogenic stimuli (mild hyperthermia). It was hypothesised that these treatments would activate glands from both skin surfaces, with the non-thermal stimulus increasing secretion rates primarily by recruiting more sweat glands. Ten healthy men participated in two seated, resting trials in temperate conditions (25-26°C). Trials commenced under normothermic conditions during which the first psychogenic stress was applied. That was followed by passive heating (0.5°C mean body temperature elevation) and thermal clamping, with a second cognitive challenge then applied. Sudomotor activity was evaluated from both hands, with colourimetry used to identify activated sweat glands, skin conductance to determine the onset of precursor sweating and ventilated sweat capsules to measure rates of discharged sweating. From glandular activation and sweat rate data, sweat-gland outputs were derived. These psychogenic and thermogenic stimuli activated sweat glands from both the glabrous and non-glabrous skin surfaces, with the former dominating at the glabrous skin and the latter at the non-glabrous surface. Indeed, those stimuli individually accounted for ~90% of the site-specific maximal number of activated sweat glands observed when both stimuli were simultaneously applied. During the normothermic psychological stimulation, sweating from the glabrous surface was elevated via a 185% increase in the number of activated glands within the first 60s. The hypothetical mechanism for this response may involve the serial activation of additional eccrine sweat glands during the progressive evolution of psychogenic sweating., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Purpose: Supra-tolerance head-to-foot directed gravitoinertial load (+Gz) typically induces a sequence of symptoms/signs, including loss of: peripheral vision-central vision-consciousness. The risk of unconsciousness is greater when anti-G-garment failure occurs after prolonged rather than brief exposures, presumably because, in the former condition, mental signs are not consistently preceded by impaired vision. The aims were to investigate if prolonged exposure to moderately elevated +Gz reduces intraocular pressure (IOP; i.e., improves provisions for retinal perfusion), or the cerebral anoxia reserve., Methods: Subjects were exposed to 4-min +Gz plateaux either at 2 and 3 G (n = 10), or at 4 and 5 G (n = 12). Measurements included eye-level mean arterial pressure (MAP), oxygenation of the cerebral frontal cortex, and at 2 and 3 G, IOP., Results: IOP was similar at 1 (14.1 ± 1.6 mmHg), 2 (14.0 ± 1.6 mmHg), and 3 G (14.0 ± 1.6 mmHg). During the G exposures, MAP exhibited an initial prompt drop followed by a partial recovery, end-exposure values being reduced by ≤30 mmHg. Cerebral oxygenation showed a similar initial drop, but without recovery, and was followed by either a plateau or a further slight decrement to a minimum of about -14 μM., Conclusion: Gz loading did not affect IOP. That cerebral oxygenation remained suppressed throughout these G exposures, despite a concomitant partial recovery of MAP, suggests that the increased risk of unconsciousness upon G-garment failure after prolonged +Gz exposure is due to reduced cerebral anoxia reserve., Competing Interests: The authors declare that they have no conflicts of interest.

Mobile phone subscriptions continue to increase across the world, with the electromagnetic fields (EMF) emitted by these devices, as well as by related technologies such as Wi-Fi and smart meters, now ubiquitous. This increase in use and consequent exposure to mobile communication (MC)-related EMF has led to concern about possible health effects that could arise from this exposure. Although much research has been conducted since the introduction of these technologies, uncertainty about the impact on health remains. The Australian Centre for Electromagnetic Bioeffects Research (ACEBR) is a National Health and Medical Research Council Centre of Research Excellence that is undertaking research addressing the most important aspects of the MC-EMF health debate, with a strong focus on mechanisms, neurodegenerative diseases, cancer, and exposure dosimetry. This research takes as its starting point the current scientific status quo, but also addresses the adequacy of the evidence for the status quo. Risk communication research complements the above, and aims to ensure that whatever is found, it is communicated effectively and appropriately. This paper provides a summary of this ACEBR research (both completed and ongoing), and discusses the rationale for conducting it in light of the prevailing science., Competing Interests: Robert McIntosh and Steve Iskra are full-time employees of Telstra Corporation. Raymond McKenzie is a full time employee of the Australian Mobile Telecommunications Association the remaining authors declare no conflict of interest.

Human heat loss is thought, in part, to be morphologically related. It was therefore hypothesized that when heat-loss requirements and body temperatures were matched, that the mass-specific surface area alone could significantly explain both cutaneous vascular and sudomotor responses during compensable exercise. These thermoeffector responses were examined in 36 men with widely varying mass-specific surface areas (range, 232.3-292.7 cm(2)/kg), but of similar age, aerobic fitness, and adiposity. Subjects completed two trials under compensable conditions (28.1°C, 36.8% relative humidity), each involving rest (20 min) and steady-state cycling (45 min) at two matched metabolic heat-production rates (light, ∼135 W/m(2); moderate, ∼200 W/m(2)). Following equivalent mean body temperature changes, forearm blood flow and vascular conductance (r = 0.63 and r = 0.65) shared significant, positive associations with the mass-specific surface area during light work (P < 0.05), explaining ∼45% of the vasomotor variation. Conversely, during light and moderate work, whole body sweat rate, as well as local sweat rate and sudomotor sensitivity at three of four measured sites, revealed moderate, negative relationships with the mass-specific surface area (correlation coefficient range -0.37 to -0.73, P < 0.05). Moreover, those relationships could uniquely account for between 10 and 53% of those sweating responses (P < 0.05). Therefore, both thermoeffector responses displayed a significant morphological dependency in the presence of equivalent thermoafferent drive. Indeed, up to half of the interindividual variation in these effector responses could now be explained through morphological differences and the first principles governing heat transfer., (Copyright © 2016 the American Physiological Society.)

The focus of this review is on the physiological considerations necessary for developing employment standards within occupations that have a heavy reliance on load carriage. Employees within military, fire fighting, law enforcement, and search and rescue occupations regularly work with heavy loads. For example, soldiers often carry loads >50 kg, whilst structural firefighters wear 20-25 kg of protective clothing and equipment, in addition to carrying external loads. It has long been known that heavy loads modify gait, mobility, metabolic rate, and efficiency, while concurrently elevating the risk of muscle fatigue and injury. In addition, load carriage often occurs within environmentally stressful conditions, with protective ensembles adding to the thermal burden of the workplace. Indeed, physiological strain relates not just to the mass and dimensions of carried objects, but to how those loads are positioned on and around the body. Yet heavy loads must be borne by men and women of varying body size, and with the expectation that operational capability will not be impinged. This presents a recruitment conundrum. How do employers identify capable and injury-resistant individuals while simultaneously avoiding discriminatory selection practices? In this communication, the relevant metabolic, cardiopulmonary, and thermoregulatory consequences of loaded work are reviewed, along with concomitant impediments to physical endurance and mobility. Also emphasised is the importance of including occupation-specific clothing, protective equipment, and loads during work-performance testing. Finally, recommendations are presented for how to address these issues when evaluating readiness for duty.

While the scope of the term physical employment standards is wide, the principal focus of this paper is on standards related to physiological evaluation of readiness for work. Common applications of such employment standards for work are in public safety and emergency response occupations (e.g., police, firefighting, military), and there is an ever-present need to maximize the scientific quality of this research. Historically, most of these occupations are male-dominated, which leads to potential sex bias during physical demands analysis and determining performance thresholds. It is often assumed that older workers advance to positions with lower physical demand. However, this is not always true, which raises concerns about the long-term maintenance of physiological readiness. Traditionally, little attention has been paid to the inevitable margin of uncertainty that exists around cut-scores. Establishing confidence intervals around the cut-score can reduce for this uncertainty. It may also be necessary to consider the effects of practise and biological variability on test scores. Most tests of readiness for work are conducted under near perfect conditions, while many emergency responses take place under far more demanding and unpredictable conditions. The potential impact of protective clothing, respiratory protection, load carriage, environmental conditions, nutrition, fatigue, sensory deprivation, and stress should also be considered when evaluating readiness for work. In this paper, we seek to establish uniformity in terminology in this field, identify key areas of concern, provide recommendations to improve both scientific and professional practice, and identify priorities for future research.

Aim : Static muscle activation elicits intensity-dependent, non-thermal sweating that is presumably controlled by feedforward (central command) mechanisms. However, it is currently unknown how the size of the recruited muscle mass interacts with that mechanism. To investigate the possible muscle-size dependency of that non-thermal sweating, the recruitment of two muscle groups of significantly different size was investigated in individuals within whom steady-state thermal sweating had been established and clamped. Methods : Fourteen passively heated subjects (climate chamber and water-perfusion garment) performed 60-s, static handgrip and knee-extension activations at 30% and 50% of maximal voluntary force, plus a handgrip at 40% intensity (143.4 N) and a third knee extension at the same absolute force. Local sweating from four body segments (averaged to represent whole-body sudomotor activity), three deep-body and eight skin temperatures, heart rates and perceptions of physical effort were measured continuously, and analyzed over the final 30 s of exercise. Results : In the presence of thermal clamping and low-level, steady-state sweating, static muscle activation resulted in exercise-intensity dependent changes in the whole-body sudomotor response during these handgrip and knee-extension actions ( P < 0.05). However, there was no evidence of a dependency on the size of the recruited muscle mass ( P > 0.05), yet both dependencies were apparent for heart rate, and partially evident for the sensations of physical effort. Conclusion : These observations represent the first evidence that exercise-related sudomotor feedforward is not influenced by the size of the activated muscle mass, but is instead primarily dictated by the intensity of the exercise itself.

Motorcycle protective clothing can be uncomfortably hot during summer, and this experiment was designed to evaluate the physiological significance of that burden. Twelve males participated in four, 90-min trials (cycling 30 W) across three environments (25, 30, 35 °C [all 40% relative humidity]). Clothing was modified between full and minimal injury protection. Both ensembles were tested at 25 °C, with only the more protective ensemble investigated at 30 and 35 °C. At 35 °C, auditory canal temperature rose at 0.02 °C min(-1) (SD 0.005), deviating from all other trials (p < 0.05). The thresholds for moderate (>38.5 °C) and profound hyperthermia (>40.0 °C) were predicted to occur within 105 min (SD 20.6) and 180 min (SD 33.0), respectively. Profound hyperthermia might eventuate in ~10 h at 30 °C, but should not occur at 25 °C. These outcomes demonstrate a need to enhance the heat dissipation capabilities of motorcycle clothing designed for summer use in hot climates, but without compromising impact protection. Practitioner's Summary: Motorcycle protective clothing can be uncomfortably hot during summer. This experiment was designed to evaluate the physiological significance of this burden across climatic states. In the heat, moderate (>38.5 °C) and profound hyperthermia (>40.0 °C) were predicted to occur within 105 and 180 min, respectively.

Purpose: Torso loads restrict chest-wall movement and ventilation, particularly during heavy exercise. Therefore, the differential impact of load carriage and chest-wall restriction was investigated during progressive treadmill exercise. In addition, acceptable work durations were derived across a wide range of submaximal, loaded exercise intensities., Methods: Twelve males participated in two research phases. Phase 1: Three incremental treadmill tests until exhaustion [control (clothing only), load carriage (clothing plus 22-kg vest), and clothing with chest strapping]. Phase 2: Five steady-state exercise trials (clothing plus 22-kg vest) at intensities from 30 to 80 % of peak aerobic power to determine maximal acceptable work durations., Results: Maximal work tolerance [control 17.21 min (±0.93); loaded 13.44 min (±0.68); strapped 17.00 min (±0.83)] and the mass-specific peak aerobic power [control 61.61 mL kg(-1) min(-1) (±2.28); loaded 45.42 mL kg(-1) min(-1) (±1.41); strapped 59.99 mL kg(-1) min(-1) (±1.61)] were reduced only when loaded (P < 0.05). Peak minute ventilation was retained, although loading and chest strapping reduced the breathing reserve. The lower and upper acceptable work duration derivations when working at the 30 % intensity were 133.40 min (±23.77) and 220.10 min (±48.69), but at 80 % intensity, both durations were reduced to <7 min., Conclusion: Thoracic loading significantly reduced exercise tolerance and the breathing reserve, but did not modify peak minute ventilation or the absolute peak aerobic power. Chest strapping, as used herein, exerted minimal impact. However, the projected maximal acceptable work durations were much less than derived using previously published methods.

This project was based on the premise that decisions concerning the ballistic protection provided to defence personnel should derive from an evaluation of the balance between protection level and its impact on physiological function, mobility, and operational capability. Civilians and soldiers participated in laboratory- and field-based studies in which ensembles providing five levels of ballistic protection were evaluated, each with progressive increases in protection, mass (3.4-11.0 kg), and surface-area coverage (0.25-0.52 m(2)). Physiological trials were conducted on volunteers (N = 8) in a laboratory, under hot-dry conditions simulating an urban patrol: walking at 4 km·h(-1) (90 min) and 6 km·h(-1) (30 min or to fatigue). Field-based trials were used to evaluate tactical battlefield movements (mobility) of soldiers (N = 31) under tropical conditions, and across functional tests of power, speed, agility, endurance, and balance. Finally, trials were conducted at a jungle training centre, with soldiers (N = 32) patrolling under tropical conditions (averaging 5 h). In the laboratory, work tolerance was reduced as protection increased, with deep-body temperature climbing relentlessly. However, the protective ensembles could be grouped into two equally stressful categories, each providing a different level of ballistic protection. This outcome was supported during the mobility trials, with the greatest performance decrement evident during fire and movement simulations, as the ensemble mass was increased (-2.12%·kg(-1)). The jungle patrol trials similarly supported this outcome. Therefore, although ballistic protection does increase physiological strain, this research has provided a basis on which to determine how that strain can be balanced against the mission-specific level of required personal protection.

Aim: The inter-relationships between mean body and local skin temperatures have previously been established for controlling hand and foot blood flows. Since glabrous skin contains many arteriovenous anastomoses, it was important to repeat those experiments on non-glabrous regions using the same sample and experimental conditions., Methods: Mild hypothermia (mean body temperature 31.4 °C), normothermia (control: 36.0 °C) and moderate hyperthermia (38.3 °C) were induced and clamped (climate chamber and water-perfusion garment) in eight males. Within each condition, five localised thermal treatments (5, 15, 25, 33, 40 °C) were applied to the left forearm and right calf. Steady-state forearm and calf blood flows were measured (venous occlusion plethysmography) for each of the resulting 15 combinations of clamped mean body and local skin temperatures., Results: Under the normothermic clamp, cutaneous blood flows averaged 4.2 mL 100 mL(-1) min(-1) (±0.28: forearm) and 5.4 mL 100 mL(-1) min(-1) (±0.27: calf). When mildly hypothermic, these segments were unresponsive to localised thermal stimuli, but tracked those changes when normothermic and moderately hyperthermic. For deep-body (oesophageal) temperature elevations, forearm blood flow increased by 5.1 mL 100 mL(-1) min(-1) °C(-1) (±0.9) relative to normothermia, while the calf was much less responsive: 3.3 mL 100 mL(-1) min(-1) °C(-1) (±1.5). Three-dimensional surfaces revealed a qualitative divergence in the control of calf blood flow, with vasoconstrictor tone apparently being released more gradually., Conclusion: These descriptions reinforce the importance of deep-tissue temperatures in controlling cutaneous perfusion, with this modulation being non-linear at the forearm and appearing linear for the calf.

INTRODUCTION:: Patient cooling time can impact upon the prognosis of heat illness. Although ice-cold-water immersion will rapidly extract heat, access to ice or cold water may be limited in hot climates. Indeed, some have concerns regarding the sudden cold-water immersion of hyperthermic individuals, whereas others believe that cutaneous vasoconstriction may reduce convective heat transfer from the core. It was hypothesized that warmer immersion temperatures, which induce less powerful vasoconstriction, may still facilitate rapid cooling in hyperthermic individuals. METHODS:: Eight males participated in three trials and were heated to an esophageal temperature of 39.5 degrees C by exercising in the heat (36 degrees C, 50% relative humidity) while wearing a water-perfusion garment (40 degrees C). Subjects were cooled using each of the following methods: air (20-22 degrees C), cold-water immersion (14 degrees C), and temperate-water immersion (26 degrees C). RESULTS:: The time to reach an esophageal temperature of 37.5 degrees C averaged 22.81 min (air), 2.16 min (cold), and 2.91 min (temperate). Whereas each of the between-trial comparisons was statistically significant (P < 0.05), cooling in temperate water took only marginally longer than that in cold water, and one cannot imagine that the 45-s cooling time difference would have any meaningful physiological or clinical implications. CONCLUSION:: It is assumed that this rapid heat loss was due to a less powerful peripheral vasoconstrictor response, with central heat being more rapidly transported to the skin surface for dissipation. Although the core-to-water thermal gradient was much smaller with temperate-water cooling, greater skin and deeper tissue blood flows would support a superior convective heat delivery. Thus, a sustained physiological mechanism (blood flow) appears to have countered a less powerful thermal gradient, resulting in clinically insignificant differences in heat extraction between the cold and temperate cooling trials. [ABSTRACT FROM AUTHOR]

There is often a fine line between providing appropriate personal protection and compromising capability. In some situations, protection must come first. In other circumstances, capability becomes paramount. In the military, mission-specific objectives can force personal protection to be less than ideal. Indeed, levels of protection appropriate within the civilian context could jeopardise health and operational success, and for operations conducted in the heat involving load carriage and armored protection with almost total-body clothing coverage, it is the likely thermal impediment to performance that perhaps first comes to mind. Although this consideration is appropriate, it may direct attention away from the actual cause of, and therefore preventative solutions to, physiological collapse. For instance, although classical heat illness absolutely occurs at the age extremes, and it may affect all people when air temperatures are exceptionally hot, frank hyperthermia is not generally the primary cause of exhaustion when healthy clothed individuals are working in the heat. Instead, another homoeostatic process is implicated; blood pressure regulation. In addition to participating in temperature regulation, the cardiovascular system supports oxygen delivery, blood pressure regulatory, and waste removal requirements. Therefore, the elevated cardiac output accompanying work must be shared. Accordingly, the case will be developed that thermoregulatory failure is often not the primary causal mechanism for soldier collapse, although such individuals may be hyperthermic. Alternatively, moderately, but not excessively, hyperthermic soldiers working under these conditions are perhaps more likely to collapse from cardiovascular insufficiency that precipitates uncompensable hypotension.

Physical fitness training of military recruits is an enduring focus of armies. This is important for safe and effective performance of general tasks that anyone may have to perform in a military setting as well as preparation for more specialized training in specific job specialties. Decades of studies on occupationally specific physical requirements have characterized the dual aerobic and strength demands of typical military tasks; however, scientifically founded strategies to prepare recruits with a good mix of these 2 physiologically opposing capabilities have not been well established. High levels of aerobic training can compromise resistance training gains and increase injury rates. Resistance training requires a greater commitment of time and resources as well as a greater understanding of the science to produce true strength gains that may be beneficial to military performance. These are critical issues for modern armies with increased demands for well-prepared soldiers and fewer injury losses. The actual physical requirements tied to metrics of success in military jobs are also under renewed examination as women are increasingly integrated into military jobs previously performed only by men. At the third International Congress on Soldiers' Physical Performance, a roundtable of 10 physiologists with military expertise presented comparative perspectives on aerobic and strength training. These topics included the physiological basis of training benefits, how to train effectively, how to measure training effectiveness, considerations for the integration of women, and the big perspective. Key discussion points centered on (a) the significance of findings from research on integrated training, (b) strategies for effective strength development, and, ((c) injury reduction in training as well as the benefits of improved fitness to injury reduction across the force.)

Sweating events occur in response to mental stress (psychogenic) or with increased body temperature (thermogenic). We previously found that both were linked to activation of common brain stem regions, suggesting that they share the same output pathways: a putative common premotor nucleus was identified in the rostral-lateral medulla (Farrell MJ, Trevaks D, Taylor NA, McAllen RM. Am J Physiol Regul Integr Comp Physiol 304: R810-R817, 2013). We therefore looked in higher brain regions for the neural basis that differentiates the two types of sweating event. Previous work has identified hemispheric activations linked to psychogenic sweating, but no corresponding data have been reported for thermogenic sweating. Galvanic skin responses were used to measure sweating events in two groups of subjects during either psychogenic sweating (n = 11, 35.3 ± 11.8 yr) or thermogenic sweating (n = 11, 34.4 ± 10.2 yr) while regional brain activation was measured by BOLD signals in a 3-Tesla MRI scanner. Common regions activated with sweating events in both groups included the anterior and posterior cingulate cortex, insula, premotor cortex, thalamus, lentiform nuclei, and cerebellum (P(corrected) < 0.05). Psychogenic sweating events were associated with significantly greater activation in the dorsal midcingulate cortex, parietal cortex, premotor cortex, occipital cortex, and cerebellum. No hemispheric region was found to show statistically significantly greater activation with thermogenic than with psychogenic sweating events. However, a discrete cluster of activation in the anterior hypothalamus/preoptic area was seen only with thermogenic sweating events. These findings suggest that the expected association between sweating events and brain regions implicated in "arousal" may apply selectively to psychogenic sweating; the neural basis for thermogenic sweating events may be subcortical., (Copyright © 2015 the American Physiological Society.)

Objective: The physiological demands of 15 essential, physically demanding fire-fighting tasks were investigated to identify criterion tasks for bona fide recruit selection., Methods: A total of 51 operational firefighters participated in discrete, field-based occupational simulations, with physiological responses measured throughout., Results: The most stressful tasks were identified and classified according to dominant fitness attributes and movement patterns. Three movement classes (single-sided load carriage [5 tasks], dragging loads [4 tasks], and overhead pushing and holding objects [2 tasks]) and one mandatory strength task emerged. Seven criterion tasks were identified. Load holding and carriage dominated these movement patterns, yet no task accentuated whole-body endurance., Conclusion: Material handling movements from each classification must appear within a physical aptitude (selection) test for it to adequately represent the breadth of tasks performed by Australian urban firefighters.

Objective: In this third communication, the processes for converting criterion occupational tasks into bona fide pre-employment selection tests are presented using urban firefighters as the worked example., Methods: A total of 14 individuals participated in potential screening tests that targeted three loaded movement categories: single-sided load carriage (4 tests), dragging loads (2 tests), and overhead pushing and holding objects (5 tests)., Results: Seven tests emerged, one performed as an isolated pass/fail barrier test (ladder raise) and six incorporated into a sequential, timed circuit simulating hazmat incidents, ventilation fan carriage (stairs), motor-vehicle rescues, bushfire incidents, fire attacks, and a firefighter rescue., Conclusion: Because three tests provided predicted performance speeds to replicate the oxygen cost of firefighters performing the corresponding occupational simulations, notional performance thresholds could be projected and recommended for the final phase of this research.

Objective: This communication is the first of four describing the development of defensible firefighter-selection tests. The purpose was to identify a subset of essential, physically demanding tasks performed by contemporary urban firefighters., Methods: From existing procedural documentation and job analyses, 11 fire-station visits and interviews with 106 firefighters, and one focus-group meeting, 31 physically demanding tasks were identified and incorporated into a workforce survey. Using this tool, firefighters rated the importance, perceived difficulty, typical task durations, and annual performance frequency of each task., Results: Data from 989 respondents were analyzed, enabling a consolidation of these tasks into a subset of essential activities., Conclusions: These processes yielded a content-valid list of 15 essential, physically demanding tasks covering the full width of duties performed by urban firefighters from Australia's largest fire and rescue organization.

Objective: Firefighter physical aptitude tests were administered to unskilled subjects and operational firefighters to evaluate the impact that testing bias associated with gender, age, activity-specific skills, or task familiarity may have upon establishing performance thresholds., Methods: These tests were administered in sequence, simulating hazmat incidents, ventilation fan carriage (stairs), motor-vehicle rescues, bushfire incidents, fire attacks, and a firefighter rescue. Participants included two unskilled samples (N = 14 and 22) and 143 firefighters., Results: Firefighter performance was not significantly different from the unskilled subjects. Participants from both genders passed the test, with scores unrelated to performance skill or age; however, familiarization significantly improved performance when the test was repeated., Conclusion: These outcomes confirmed this test to be gender-, age-, and skill-neutral. Familiarization effects could be removed through performing a single, pre-selection trial of the test battery.

In the preceding communication, an investigation was described in which the thermal specifications for the design of private bushfire shelters were evaluated. Since those trials were undertaken with the thermal characteristics of the air clamped, survival uncertainty persisted if the internal ambient conditions were progressively changing, as would occur within an air-tight shelter. Therefore, two further investigations were performed. In the first, changes in the physical properties of air within an air-tight shelter simulator (1.2 m(3)), initially equilibrated to 43.7 °C and 42.3 % relative humidity, were studied when pre-heated, well-hydrated males were sealed inside (N = 16; 60 min; experimental series 2). Air temperature and humidity moved sigmoidally to 40.5 °C (standard deviation (SD), 0.5) and 90.1 % (SD, 2.1). Oxygen and carbon dioxide fractional concentrations changed reciprocally, with respective terminal averages of 16.7 % (SD, 0.8) and 3.94 % (SD, 0.72). Deep-body temperature rose beyond the tenth minute to a terminal mean of 39.3 °C (SD, 0.2). In the third experimental series, these air temperature and humidity changes were reproduced in trials commencing at two different thermal states (40 °C and 70 % relative humidity; 45 °C and 50 % relative humidity). Sixteen pre-heated and slightly dehydrated men and women were investigated. In neither condition did the auditory canal temperature of any individual change by more than 2 °C or exceed 40 °C. It may be concluded, within the limits of these experiments, that the recommended thermal and dimensional specifications for bushfire shelters can provide tenable conditions for healthy, young adults.