Thermoneutral zone for laying hens based on environmental conditions, enthalpy and thermal comfort indexes.

Controlling environmental conditions inside laying hens facilities systems and their effects on physiology and performance is essential in defining management strategies to alleviate the adverse effects of thermal stress in laying hens. Thus, we estimated thermoneutral zones for laying hens exposed to different heat-challenging conditions based on environmental conditions, enthalpy, and thermal comfort indexes being evaluated out in four thermal environment-controlled wind tunnels equipped with heating and air moistening function, housed in an experimental room with an area of 31.92 m2. Clustering analysis and empirical models were used to estimate thermoneutral zones for laying hens based on environmental conditions, enthalpy and thermal comfort indexes, and compare them with data available in the literature through graphics. The thermoneutral zones characterizing homeostasis for laying hens based on respiration rate (RR) are as follows: from 25.9 to 29.9 °C for air dry-bulb temperature (tdb), from 67 to 75 for temperature-humidity index (THI), from 68 to 73 for black globe-humidity index (BGHI), from 45 to 56 kJ kg dry air-1 for enthalpy (H) and 441.7-465.6 W for radiant heat load (RHL). Comfort limits for physiological responses cloacal temperature (tclo), surface temperature (tsur) and RR found in this study are 39.4-39.9 °C, 26.5 to 29.9 °C and 30 to 67 mov. min-1, respectively. The number of repetitions and the use of mathematical modeling to be worked on, may directly impact the amplitude of each limit to be established for each variable of interest.

The associations between thermal variety and health: Implications for space heating energy use.

Fossil fuels dominate domestic heating in temperate climates. In the EU, domestic space heating accounts for around 20% of final energy demand. Reducing domestic demand temperatures would reduce energy demand. However, cold exposure has been shown to be associated with adverse health conditions. Using an observational dataset of 77,762 UK Biobank participants, we examine the standard deviation of experienced temperature (named here thermal variety) measured by a wrist worn activity and temperature monitor. After controlling for covariates such as age, activity level and obesity, we show that thermal variety is 0.15°C 95% CI [0.07-0.23] higher for participants whose health satisfaction was 'extremely happy' compared to 'extremely unhappy'. Higher thermal variety is also associated with a lower risk of having morbidities related to excess winter deaths. We argue that significant CO2 savings would be made by increasing thermal variety and reducing domestic demand temperatures in the healthiest homes. However, great care is needed to avoid secondary health impacts due to mould and damp. Vulnerable households should receive increased attention.

Back to Normal: An Old Physics Route to Reduce SARS-CoV-2 Transmission in Indoor Spaces.

We advocate the widespread use of UV-C light as a short-term, easily deployable, and affordable way to limit virus spread in the current SARS-CoV-2 pandemic. Radical social distancing with the associated shutdown of schools, restaurants, sport clubs, workplaces, and traveling has been shown to be effective in reducing virus spread, but its economic and social costs are unsustainable in the medium term. Simple measures like frequent handwashing, facial masks, and other physical barriers are being commonly adopted to prevent virus transmission. However, their efficacy may be limited, particularly in shared indoor spaces, where, in addition to airborne transmission, elements with small surface areas such as elevator buttons, door handles, and handrails are frequently used and can also mediate transmission. We argue that additional measures are necessary to reduce virus transmission when people resume attending schools and jobs that require proximity or some degree of physical contact. Among the available alternatives, UV-C light satisfies the requirements of rapid, widespread, and economically viable deployment. Its implementation is only limited by current production capacities, an increase of which requires swift intervention by industry and authorities.

Data-Driven Living Spaces' Heating Dynamics Modeling in Smart Buildings using Machine Learning-Based Identification.

Modeling and control of the heating feature of living spaces remain challenging tasks because of the intrinsic nonlinear nature of the involved processes as well as the strong nonlinearity of the entailed dynamic parameters in those processes. Although nowadays, adaptive heating controllers represent a crucial need for smart building energy management systems (SBEMS) as well as an appealing perspective for their effectiveness in optimizing energy efficiency, unfortunately, the leakage of models competent in handling the complexity of real living spaces' heating processes means the control strategies implemented in most SBEMSs are still conventional. Within this context and by considering that the living space's occupation rate (i.e., by users or residents) may affect the model and the issued heating control strategy of the concerned living space, we have investigated the design and implementation of a data-driven machine learning-based identification of the building's living space dynamic heating conduct, taking into account the occupancy (by the residents) of the heated space. In fact, the proposed modeling strategy takes advantage, on the one hand, of the forecasting capacity of the time-series of the nonlinear autoregressive exogenous (NARX) model, and on the other hand, from the multi-layer perceptron's (MLP) learning and generalization skills. The proposed approach has been implemented and applied for modeling the dynamic heating conduct of a real five-floor building's living spaces located at Senart Campus of University Paris-Est Créteil (UPEC), taking into account their occupancy (by users of this public building). The obtained results assessing the accuracy and addictiveness of the investigated hybrid machine learning-based approach are reported and discussed.

Newborn Service Readiness of Primary Level Health Facilities of Eastern Mountain Region of Nepal.

BACKGROUND: Newborn service readiness is facility's observed capacity to provide newborn services and a pre-requisite for quality. Newborn services are priority program of government and efforts are focused on infrastructure and supplies at peripheral health facilities. Study describes health facility readiness for newborn services in four domains of general requirements, equipment, medicines and commodities, and staffing and guidelines. METHODS: Convergent parallel mixed method using concurrent triangulation was done in public health facilities providing institutional deliveries of two randomly selected districts- Taplejung and Solukhumbu of Eastern Mountain Region of Nepal. Face to face interview and observation of facilities were done using structured questionnaire and checklist; in-depth interviews were done using interview guideline from November 2016 to January 2017. Ethical clearance was taken. Descriptive analysis and deductive thematic analysis were done. RESULTS: Mean score of newborn service readiness was 68.7±7.1 with range from 53.3 to 81.4 out of 100. Domains of general requirement, equipment, medicine and commodity, supervision, staffing and guideline were assessed. The gaps identified in general requirements were availability of uninterrupted power supply, means of communication and referral vehicle. Clean wrappers and heater for room temperature maintenance were identified during interviews to be part of the readiness. All health facilities had trained staff while retention of skill was of concern. There was felt need of enforcing adequate training coverage to suffice the need of human resources in remote. CONCLUSIONS: Efforts of improving transportation, heater for room temperature maintenance, trainings with skill retention strategy, utilization of guidelines, availability of skilled birth attendance could result increased and improved newborn service readiness.

Identification of local thermal conditions for sleeping comfort improvement in neutral to cold indoor thermal environments.

The effect of the thermal environment on sleep quality has attracted considerable attention, as sleep forms one-third of human lifetime and the occupied space is largely constrained during sleep. With an increasing development of partial space regulation and task air conditioning systems and devices, thermal comfort demand concerning local thermal conditions has attracted more and more attention. In the present study, experiment was conducted and data mining technologies were performed to investigate correlations between local thermal conditions and whole body thermal comfort in sleeping state. The identification of local thermal condition included two steps: the first step was to clarify thermal sensation links between local and covered body, and the second step was to identify local thermal sensation inclination towards different thermal comfort levels. Thermal sensation correlations among local body parts and covered body were obtained. Back, face, and thigh were identified as three dominant linear-correlated local parts with weighting factors 0.488, 0.388, and 0.152, respectively; in addition, chest, arm, leg and foot were found as non-negligible local parts in the estimation of covered body thermal sensation. By dividing the sleeping human body into three parts as head, trunk and extremity, the proper local thermal sensations and their coupling relationships for whole body sleeping thermal comfort have been elaborated by three rules. The present study provides implications in sleeping thermal environment regulation in neutral to cold indoor conditions.

Comparing Forced-Air to Resistive-Polymer Warming for Perioperative Temperature Management: A Retrospective Study.

PURPOSE: Compare perioperative temperature management between forced-air warming (FAW) and resistive-polymer heating blankets (RHBs). DESIGN: A retrospective, quasi-experimental study. METHODS: Retrospective data analysis of nonspine orthopedic cases (N = 426) over a one-year period including FAW (n = 119) and RHBs (n = 307). FINDINGS: FAW was associated with a significantly higher final intraoperative temperature (P = .001, d = 0.46) than the RHB. The incidence of hypothermia was not found to be significantly different at the end (P = .102) or anytime throughout surgery (P = .270). Of all patients who started hypothermic, the FAW group had a lower incidence of hypothermia at the end of surgery (P = .023). CONCLUSIONS: FAW was associated with higher final temperatures and a greater number of normothermic patients than RHBs. However, no causal relationship between a warming device and hypothermia incidence should be assumed.

Humidification in Very-High-Flow Nasal-Cannula Therapy in an Adult Lung Model.

BACKGROUND: High-flow nasal cannula (HFNC) therapy is used for patients with respiratory failure. Recently, HFNC therapy with very high gas flows (ie, gas flows of 60-100 L/min) was reported to generate higher positive airway pressure and an associated decrease in breathing frequency. However, the humidification of HFNC therapy with very high gas flow remains to be clarified. METHODS: We evaluated 3 heated humidifier systems: a single MR850, the Hummax2, and parallel MR850s. The MR850 is a pass-over humidifier system, and the Hummax2 works with a porous hollow polyethylene fiber membrane. The parallel MR850 system included 2 MR850s connected in parallel to the lung with a 22 mm Y-piece. Gas flow was set at 40-90 L/min in increments of 10 L/min, and FIO2 was set at 0.21. Heated humidifiers in the MR850 systems were set in invasive mode (40°C/-3), and with the Hummax2 the vapor temperature was set at 39°C. The simulated external nares were connected to a test lung via a standard ventilator circuit. One-way valves prevented mixing of inspired and expired gases. Compliance of the test lung was 0.05 L/cm H2O and resistance 5 cm H2O/L/s. Simulated tidal volumes (VT) were 300, 500, and 700 mL, with a breathing frequency of 10 or 20 breaths/min and an inspiratory time of 1.0 s. Temperature, relative humidity, and absolute humidity (AH) of inspired gas downstream of the external nares were measured using a hygrometer for 1 min, and results for the last 3 breaths were extracted. RESULTS: With the single MR850, when gas flow was > 80 L/min, AH decreased as gas flow increased (P < .001). With the Hummax2, as gas flow increased, AH decreased (P < .001). With the parallel MR850s, regardless of gas flow, AH was constant. As breathing frequency increased, AH increased in all systems. CONCLUSIONS: During HFNC therapy with very high gas flows in this bench study, conventional heated humidifiers did not provide adequate humidification. Caution is advised when using HFNC therapy with very high gas flows with conventional heated humidifiers.

Indoor Air Quality in the Hospital: The Influence of Heating, Ventilating and Conditioning Systems

Abstract Clean, fresh air is the most important requirement for good indoor air quality (IAQ) in all buildings, but it is especially important with regard to the environments within hospitals and other healthcare facilities. The literature indicates that buildings with heating, ventilating and air conditioning (HVAC) systems may have an increased risk of sick building syndrome (SBS) and building-related illness (BRI) if they are not well maintained. Microorganisms are brought into hospitals by people, air currents, water, construction materials and equipment. The main objective of this study was to assess the degree of fungal and bacterial contamination in the University Clinical Centre in Banja Luka, which is directly connected to the HVAC system. Airborne bacteria and fungi in the indoor hospital environment were assessed experimentally. Air samples were collected during the winter season. This paper presents the results related to the concentration of microorganisms expressed in colony forming units per cubic metre of air sampled (in CFU/m3) together with the microclimatic parameters temperature and relative humidity. The results of monitoring indicate the effectiveness of HVAC systems in reducing microbiological contamination.

Heating, ventilation and air conditioning (HVAC) system, microbial air contamination and surgical site infection in hip and knee arthroplasties: the GISIO-SItI Ischia study.

BACKGROUND: Recent studies have questioned the role of unidirectional airflow ventilation system in reducing surgical site infection (SSI) in prosthetic implant surgery. The aim of the ISChIA study ("Infezioni del Sito Chirurgico in Interventi di Artroprotesi" which means "Surgical site infections in arthroplasty surgery") was to evaluate, as a contribution to this debate, the association between heating, ventilation and air conditioning systems, microbial air contamination and surgical site infection in hip and knee arthroplasty. METHODS: The study was performed from March 2010 to February 2012 in 14 hospitals, for a total of 28 operating theatres: 16 were equipped with vertical unidirectional airflow ventilation (U-OTs), 6 with mixed airflow ventilation (M-OTs), 6 with turbulent airflow ventilation (T-OTs). Microbial air contamination in the operating theatre was evaluated by means of passive (Index of Microbial Air contamination, IMA) and active (Colony Forming Units per cubic metre, cfu/m3) sampling. SSI surveillance was carried out according to the Hospitals in Europe Link for Infection Control through Surveillance protocol. RESULTS: A total of 1,285 elective prosthesis procedures (61.1% hip and 38.9% knee) were included in the study. The results showed a wide variability of the air microbial contamination in operating theatres equipped with unidirectional airflow. The recommended values of ≤2 IMA and ≤10 cfu/m3 were exceeded, respectively, by 58.9% and 46.4% of samples from U-OTs and by 87.6% and 100% of samples from M-OTs. No significant difference was observed between SSI cumulative incidence in surgical procedures performed in U-OTs compared with those performed in T-OTs. A lower risk of SSI, even though not statistically significant, was shown in surgical procedures performed in U-OTs with a microbial air contamination within the recommended values (≤2 IMA and ≤10 cfu/m3) compared with those performed in U-OTs where these limits were exceeded, and compared with those performed in T-OTs with microbial air contamination within the recommended values for this type of OTs (≤25 IMA, ≤180 cfu/m3. CONCLUSION: ISChIA study did not show a protective effect of unidirectional airflow compared with turbulent airflow in arthroplasty surgery. However, the frequent exceeding of recommended air microbial contamination values in OTs equipped with unidirectional airflow, and the lower SSI risk in surgical procedures performed in compliant U-OTs compared with those performed in non-compliant U-OTs and with those performed in compliant T-OTs, suggest the need of further studies, which should consider air microbial contamination and other aspects of SSI prevention that may negate the potential benefits of the ventilation system; differences in intrinsic and extrinsic risk factors, medical treatment and surgical technique are also to be considered. Training interventions aimed at improving the behaviour of operators are essential.

Comparison of the performance of battery-operated fluid warmers.

OBJECTIVES: Warming intravenous fluids is essential to prevent hypothermia in patients with trauma, especially when large volumes are administered. Prehospital and transport settings require fluid warmers to be small, energy efficient and independent of external power supply. We compared the warming properties and resistance to flow of currently available battery-operated fluid warmers. METHODS: Fluid warming was evaluated at 50, 100 and 200 mL/min at a constant input temperature of 20°C and 10°C using a cardiopulmonary bypass roller pump and cooler. Output temperature was continuously recorded. RESULTS: Performance of fluid warmers varied with flows and input temperatures. At an input temperature of 20°C and flow of 50 mL/min, the Buddy Lite, enFlow, Thermal Angel and Warrior warmed 3.4, 2.4, 1 and 3.6 L to over 35°C, respectively. However, at an input temperature of 10°C and flow of 200 mL/min, the Buddy Lite failed to warm, the enFlow warmed 3.3 L to 25.7°C, the Thermal Angel warmed 1.5 L to 20.9°C and the Warrior warmed 3.4 L to 34.4°C (p<0.0001). CONCLUSION: We found significant differences between the fluid warmers: the use of the Buddy Lite should be limited to moderate input temperature and low flow rates. The use of the Thermal Angel is limited to low volumes due to battery capacity and low output temperature at extreme conditions. The Warrior provides the best warming performance at high infusion rates, as well as low input temperatures, and was able to warm the largest volumes in these conditions.

Differences in Temperature Changes in Premature Infants During Invasive Procedures in Incubators and Radiant Warmers.

Premature infants tend to lose heat quickly. This loss can be aggravated when they have received an invasive procedure involving a venous puncture. This research uses crossover design by conducting 2 intervention tests to compare 2 different treatments on the same sample. This research involved 2 groups with 18 premature infants in each. The process of data analysis used a statistical independent t test. Interventions conducted in an open incubator showed a p value of .001 which statistically related to heat loss in premature infants. In contrast, the radiant warmer p value of .001 statistically referred to a different range of heat gain before and after the venous puncture was given. The radiant warmer saved the premature infant from hypothermia during the invasive procedure. However, it is inadvisable for routine care of newborn infants since it can increase insensible water loss.

Costs and outcomes of improving population health through better social housing: a cohort study and economic analysis.

OBJECTIVES: We sought to determine the impact of warmth-related housing improvements on the health, well-being, and quality of life of families living in social housing. METHODS: An historical cohort study design was used. Households were recruited by Gentoo, a social housing contractor in North East England. Recruited households were asked to complete a quality of life, well-being, and health service use questionnaire before receiving housing improvements (new energy-efficient boiler and double-glazing) and again 12 months afterwards. RESULTS: Data were collected from 228 households. The average intervention cost was £3725. At 12-month post-intervention, a 16% reduction (-£94.79) in household 6-month health service use was found. Statistically significant positive improvements were observed in main tenant and household health status (p < 0.001; p = 0.009, respectively), main tenant satisfaction with financial situation (p = 0.020), number of rooms left unheated per household (p < 0.001), frequency of household outpatient appointments (p = 0.001), and accident/emergency department attendance (p < 0.012). CONCLUSIONS: Warmth-related housing improvements may be a cost-effective means of improving the health of social housing tenants and reducing health service expenditure, particularly in older populations.

Minimum indoor temperature threshold recommendations for English homes in winter - A systematic review.

OBJECTIVES: To identify and assess the available evidence on the impacts of cold indoor temperature thresholds on human health and make evidence-based recommendations for English homes. STUDY DESIGN: Systematic literature review. METHODS: A systematic search of peer-reviewed published literature from the UK and countries with similar climates, and grading of the evidence using the National Institute of Health (NIH) framework was followed by a discussion with experts and formulation of recommendations. RESULTS: Twenty papers were included. Studies were included if they were conducted outside England but were from countries considered to have similar climates. Studies included two small randomised controlled trials, two cohort studies and one case control study; other studies were cross-sectional, largely laboratory-based studies. Health effects in the general population start to occur at around 18 °C. Effects in older people are more profound than in younger adults. Older people are less able to perceive low temperatures. DISCUSSION: Although evidence was limited, a strong argument for setting thresholds remains. The effects observed on the general population and the effects on those more vulnerable makes a case for a recommended minimum temperature for all. Health messages should be clear and simple, allowing informed choices to be made. A threshold of 18 °C was considered the evidence based and practical minimum temperature at which a home should be kept during winter in England. CONCLUSION: There is limited evidence available on minimum temperature thresholds for homes. However a recommendation of at least 18 °C for the whole population with nuancing of messages for those more vulnerable to the effects of cold can be made from the results of the retrieved studies. RECOMMENDATION: Heating homes to at least 18 °C (65 °F) in winter poses minimal risk to the health of a sedentary person, wearing suitable clothing.

Maternal depression as a risk factor for children's inadequate housing conditions.

Depression among mothers with young children is an important public health issue that not only has implications for their own well-being, but can also potentially affect their children's health and developmental trajectories. This study explored the extent to which maternal depression is a risk factor for inadequate housing conditions related to utilities, a noteworthy risk factor for poor child health. Using data on 2965 mothers and children from a national urban cohort of U.S. births in 1998-2000, we estimated multivariate logistic regression models of associations between maternal depression during the postpartum year and a U.S. Department of Housing and Urban Development (HUD) measure of severely inadequate housing due to heating issues, as well as a broader measure of energy insecurity that encompasses various types of utility problems. We also considered outcomes that incorporated housing instability and food insecurity in conjunction with housing inadequacy. Mothers who experienced depression had about 60% higher odds of experiencing severely inadequate housing due to heat (OR: 1.57) and 70% higher odds of experiencing energy insecurity (OR: 1.69) compared to mothers who did not experience depression. Maternal depression was even more strongly associated with multiple hardships in the forms of housing inadequacy plus housing instability and/or food insecurity than it was with housing inadequacy. This study provides robust evidence that maternal depression is a risk factor for inadequate housing and multiple hardships during a critical period of children's development. The findings suggest that policy efforts should not occur in mental health, housing, and food security silos.

Thermal environment in eight low-energy and twelve conventional Finnish houses.

We assessed the thermal environment of eight recently built low-energy houses and twelve conventional Finnish houses. We monitored living room, bedroom and outdoor air temperatures and room air relative humidity from June 2012 to September 2013. Perceived thermal environment was evaluated using a questionnaire survey during the heating, cooling and interim seasons. We compared the measured and perceived thermal environments of the low-energy and conventional houses. The mean air temperature was 22.8 °C (21.9-23.8 °C) in the low-energy houses, and 23.3 °C (21.4-26.5 °C) in the conventional houses during the summer (1. June 2013-31. August 2013). In the winter (1. December 2012-28. February 2013), the mean air temperature was 21.3 °C (19.8-22.5 °C) in the low-energy houses, and 21.6 °C (18.1-26.4 °C) in the conventional houses. The variation of the air temperature was less in the low-energy houses than that in the conventional houses. In addition, the occupants were on average slightly more satisfied with the indoor environment in the low-energy houses. However, there was no statistically significant difference between the mean air temperature and relative humidity of the low-energy and conventional houses. Our measurements and surveys showed that a good thermal environment can be achieved in both types of houses.

[Amendments to the Drinking Water Ordinance: Legionellae in Hot Water Systems - Data from the Public Health Authority Frankfurt am Main, Germany]. / Änderungen der Trinkwasserverordnung: Legionellen in Großanlagen - Erfahrungen aus dem Gesundheitsamt Frankfurt am Main.

BACKGROUND: The first and second amendment to the Drinking Water Ordinance came in to force in the years 2011 and 2012 causing additional tasks and responsibilities for operators of commercial large-scale systems, usually hot water systems in large residential buildings, and for the local health authorities. This article describes the experiences of the health authority in Frankfurt/Main with these new regulations. Some of the revisions in the first amendment of the ordinance (TrinkwV 2001 (2011)) were omitted in the second revision (TrinkwV 2001 (2012)) such as the obligation to notify for large-scale systems. Furthermore, the intervals between the obligatory inspections were extended from 1 to 3 years and merely exceedances of the legal limits were to be notified in contrast to the previous obligation to notify all values. RESULTS: On the basis of the TrinkwV 2001 (2011) a large additional staff requirement had been estimated (13/21 positions). After the TrinkwV 2001 (2012) the tasks can be accomplished by less than 2 employees. While the notification obligation was still in force, the health authority received 4,461 notifications of large-scale systems, since then a further 477 have been notified. Of a total of 1,335 initial analyses, 794 (60%) exceeded the technical action value and in 113 properties with values exceeding 10,000/100 ml a usage restriction was necessary. CONCLUSIONS: Due to the suspension of the notification obligation to report any result of the analyses performed the assessment of the reports on large-scale systems has become difficult. An appropriate assessment of the implementation of the regulation is not possible, since the total number of large-scale systems is not known and a failure to report may result from a measured value below the technical action value as well as from a not inspected system. The large number of usage restrictions is an indication for the necessity to inspect and if required to treat and restore the system.

A correlation linking the predicted mean vote and the mean thermal vote based on an investigation on the human thermal comfort in short-haul domestic flights.

The results of an experimental investigation on the human thermal comfort inside the cabin of some Airbus A319 aircrafts during 14 short-haul domestic flights, linking various Italian cities, are presented and used to define a correlation among the predicted mean vote (PMV), a procedure which is commonly used to assess the thermal comfort in inhabited environments, and the equivalent temperature and mean thermal vote (MTV), which are the parameters suggested by the European Standard EN ISO 14505-2 for the evaluation of the thermal environment in vehicles. The measurements of the radiant temperature, air temperature and relative humidity during flights were performed. The air temperature varied between 22.2 °C and 26.0 °C; the relative humidity ranged from 8.7% to 59.2%. The calculated values of the PMV varied from -0.16 to 0.90 and were confirmed by the answers of the passengers. The equivalent temperature was evaluated using the equations of Fanger or on the basis of the values of the skin temperature measured on some volunteers. The correlation linking the thermal sensation scales and zones used by the PMV and the MTV resulted quite accurate because the minimum value of the absolute difference between such environmental indexes equalled 0.0073 and the maximum difference did not exceed the value of 0.0589. Even though the equivalent temperature and the MTV were specifically proposed to evaluate the thermal sensation in vehicles, their use may be effectively extended to the assessment of the thermal comfort in airplanes or other occupied places.