Analysis of air temperature changes on blood pressure and heart rate and performance of undergraduate students

Associations of Personal Hourly Exposures to Air Temperature and Pollution with Resting Heart Rate in Chronic Obstructive Pulmonary Disease

Previous studies linked higher daily ambient air temperature and pollution with increased cardiorespiratory morbidity, but immediate effects of personal, hourly exposures on resting heart rate remained unclear. We followed 30 older former smokers with chronic obstructive pulmonary disease (COPD) in Massachusetts for four nonconsecutive 30-day periods over 12 months, collecting 54,487 hourly observations of personal air temperature, fine particulate matter (PM2.5), nitrogen dioxide (NO2), ozone (O3), and resting heart rate. We explored the single lag effects (0-71 h) and cumulative effects (0-5 h, the significant lag windows) of air temperature and pollution on resting heart rate using generalized additive mixed models with distributed lag nonlinear models. Single lag effects of higher air temperature and pollutants on higher resting heart rate were most pronounced at lag 0 to 5 h. Cumulative effects of higher air temperature, PM2.5, O3, and NO2 (each interquartile range increment) on higher resting heart rate at lag 0-5 h, show differences of (beats per minute [bpm], 95% CI) 1.46 (1.31-1.62), 0.35 (0.32-0.39), 2.32 (2.19-2.45), and 1.79 (1.66-1.92), respectively. In conclusion, higher personal hourly air temperature, PM2.5, O3, and NO2 exposures at lag 0-5 h are associated with higher resting heart rate in COPD patients.

Effects of different extreme cold exposure on heart rate variability

Frequent extreme cold events in recent years have brought serious threats to outdoor workers and rescuers. Changes in ambient temperature are associated with altered cardiac autonomic function. The study aims to investigate heart rate variability (HRV) and its relationship to other physiological parameters under extreme cold exposures. Twelve males underwent a 30-min preconditioning phase in a neutral environment followed by a 30-min cold exposure (-5, -10, -15, and -20 °C). Time-domain indexes(meanRR, SDNN, RMSSD, and pNN50), frequency domain indexes [Log(HF), Log(LF), and low frequency/high frequency (LF/HF)], parasympathetic nervous system (PNS), and sympathetic nervous system (SNS) were analysed. Results showed all HRV indexes of four cold exposures were significant. The decrease in temperature was accompanied by progressive PNS activation with SNS retraction. SDNN was the most sensitive HRV index and had good linear relationships with blood pressure, pulse, and hand temperature. The results are significant for formulating safety protection strategies for workers in extremely cold environments.Practitioner Summary: This study investigated heart rate variability (HRV) in 12 males during a 30-min cold exposure (-5, -10, -15, and -20 °C). Results showed all HRV indexes of four cold exposures were significant. The decrease in temperature was accompanied by progressive PNS activation with SNS retraction. SDNN was the most sensitive HRV index and had good linear relationships with blood pressure, pulse, and hand temperature.

Influence of environmental variables on students' cognitive performance in indoor higher education environments

BACKGROUND

Educational environments can have environmental conditions that are incompatible with the needs of students, compromising their well-being and affecting their performance.

OBJECTIVE

To identify the environmental variables that influence the performance of university students and measure this influence through an experiment in indoor environments.

METHODS

The study applied an experimental methodology for three consecutive days in seven educational environments located in different regions of Brazil, measuring the environ-mental conditions, the students' perception of the environment, and their cognitive performance. The impact of environmental variables and environmental perception on student performance was analyzed using Generalized Linear Models and a Structural Equation Model.

RESULTS

Students who took the test at air temperatures between 22.4°C and 24.7°C had a 74.20% chance of performing better than those outside this range. Air temperatures between 26.2°C and 29°C were associated with an 86% chance of taking less time to complete the test. High illuminance levels increased the chance of taking longer to answer the test by 41.7%.

CONCLUSIONS

Three environmental variables (relative humidity, lighting and air temperature) and two perceptual dimensions (light and thermal perception) directly influence student performance.

Effects of wearing medical gowns at different temperatures on the physiological responses of female healthcare workers during the COVID-19 pandemic

BACKGROUND

Using medical gowns with high protection against COVID-19 among healthcare workers (HCWs) may limit heat exchange, resulting in physiological challenges.

OBJECTIVE

This study aimed to compare the physiological and neurophysiological responses of female HCWs when using two typical medical gowns at different temperatures during the COVID-19 pandemic.

METHODS

Twenty healthy female HCWs participated in this study. Participants wore two types of medical gowns: Spunbond gown (SG) and laminate gown (LG). They walked on a treadmill in a controlled climate chamber for 30 minutes at three different temperatures (24, 28, and 32°C). Heart rate (HR), skin surface temperature (ST), clothing surface temperature (CT), ear temperature (ET), blood oxygen percentage (SaO2), galvanic skin response (GSR), and blood pressure were measured before and after walking on a treadmill. The study's results were analyzed using SPSS26.

RESULTS

The study found that LG led to an average increase of 0.575°C in CT compared to SG at the same temperatures (P < 0.03). The average HR increased by 6.5 bpm in LG at 28°C compared to SG at a comfortable temperature (P = 0.01). The average ET in SG and GSR in LG at 32°C increased by 0.39°C and 0.25μS, respectively, compared to the comfortable temperature (P < 0.02).

CONCLUSION

The study recommends maintaining a comfortable temperature range in hospitals to prevent physiological challenges among HCWs wearing medical gowns with high protection against COVID-19. This is important because using LG, compared to SG, at high temperatures can increase HR, ET, CT, and GSR.

Impact of thermal comfort on online learning performance

Online learning has drawn much more attention since the outbreak of COVID-19. Most related studies have focused on online platform design and instructional design. However, the physical environment where online learning is conducted (e.g., students' homes) is rarely studied. To understand the thermal conditions in students' online learning environment and its impact on students' thermal comfort and their performance during online learning, an experiment, including both objective measurement and subjective assessment, was conducted in a student's apartment. Thirty university students participated in this experiment, and they were randomly assigned into six groups (three thermal conditions (i.e., control, cold, and hot) × two-course durations). Both environmental parameters (i.e., air temperature, radiant temperature, air velocity, etc.) and physiological parameters (i.e. skin temperatures) were measured at the same time. Besides, students' thermal sensation, acceptance, and learning performance were self-evaluated and collected through questionnaires. Results showed that participants' thermal sensation was positively correlated with their mean skin temperature (MST) and the operative temperature (T_o) in the apartment (MST: ρ = 0.94, p < 0.001; T_o: ρ = 0.91, p < 0.001), yet no significant relation with their personal characteristics was observed in the current study, which might be caused by the small sample size. Moreover, inverted U-shape relationships were identified between participants' perceived performance and their thermal sensation/MST/T_o. When students felt slightly cool (TSV = -0.3), they thought they could reach their best performance. This study revealed the impacts of the thermal environment on students' online learning performance, more performance tasks could be conducted in the future to examine the impacts in more detail.

Quantitative analysis of the influence of air temperature variability on thermal perception of Brazilian university students

BACKGROUND: The scientific literature has already identified the influence of thermal conditions on health and performance of students. However, users’ opinions are often overwhelmed by normative evaluations, not receiving the necessary attention. OBJECTIVE: To quantitatively compare the influence of air temperature variability on the thermal perception of students from six air-conditioned teaching environments located in four regions of Brazil. METHODS: Three-day experiments were carried out in six environments. A thermal condition was proposed for each day. From that, the environmental parameters were measured and a questionnaire about the thermal perception was applied. Then, Generalized Linear Models were applied to obtain a measure of effect and hypothesis test and confidence interval were used to find comfort zones and compare environments. RESULTS: The results showed that students from environments A, B, C and E felt less the effects of the increase in air temperature compared to students from environments D and F. In addition, students from environments A, B, C and E showed less perceptual variability compared to students from environments D and F. CONCLUSIONS: Students acclimated to higher thermal conditions felt less the effects of the increase in air temperature, showed less perceptual variability and a higher degree of thermal adaptability.

A systematic approach to quantify the influence of indoor environmental parameters on students' perceptions, responses, and short-term academic performance

Several studies found that classrooms' indoor environmental quality (IEQ) can positively influence in-class activities. Understanding and quantifying the combined effect of four indoor environmental parameters, namely indoor air quality and thermal, acoustic, and lighting conditions on people is essential to create an optimal IEQ. Accordingly, a systematic approach was developed to study the effect of multiple IEQ parameters simultaneously. Methods for measuring the IEQ and students' perceived IEQ, internal responses, and academic performance were derived from literature. Next, this systematic approach was tested in a pilot study during a regular academic course. The perceptions, internal responses, and short-term academic performance of participating students (n = 163) were measured. During the pilot study, the IEQ of the classrooms varied slightly. Significant associations (p < 0.05) were observed between these natural variations and students' perceptions of the thermal environment and indoor air quality. These perceptions were significantly associated with their physiological and cognitive responses (p < 0.05). Furthermore, students' perceived cognitive responses were associated with their short-term academic performance (p < 0.01). The observed associations confirm the construct validity of the systematic approach. However, its validity for investigating the influence of lighting remains to be determined.

Effects of a cool classroom microclimate on cardiac autonomic control and cognitive performances in undergraduate students

An inverted U-shape relationship between cognitive performance and indoor temperature with best performance peaking at 21.6 °C was previously described. Little is known on classroom temperature reduction effects on cognitive performances and cardiac autonomic profile, during the cold season. Fifteen students underwent electrocardiogram recording during a lecture in two days in December when classroom temperatures were set as neutral (NEUTRAL, 20-22 °C) and cool (COOL, 16-18 °C). Cognitive performance (memory, verbal ability, reasoning, overall cognitive C-score) was assessed by Cambridge Brain Science cognitive evaluation tool. Cardiac autonomic control was evaluated via the analysis of spontaneous fluctuations of heart period, as the temporal distance between two successive R-wave peaks (RR). Spectral analysis provided the power in the high frequency (HF, 0.15-0.40 Hz) and low frequency (LF, 0.04-0.15 Hz) bands of RR variability. Sympatho-vagal interaction was assessed by LF to HF ratio (LF/HF). Symbolic analysis provided the fraction of RR patterns composed by three heart periods with no variation (0 V%) and two variations (2 V%), taken as markers of cardiac sympathetic and vagal modulations, respectively. The students' thermal comfort was assessed during NEUTRAL and COOL trials. Classroom temperatures were 21.5 ± 0.8 °C and 18.4 ± 0.4 °C during NEUTRAL and COOL. Memory, verbal ability, C-Score were greater during COOL (13.01 ± 3.43, 12.32 ± 2.58, 14.29 ± 2.90) compared to NEUTRAL (9.98 ± 2.26, p = 0.002; 8.57 ± 1.07, p = 0.001 and 10.35 ± 3.20, p = 0.001). LF/HF (2.4 ± 1.7) and 0 V% (23.2 ± 11.1%) were lower during COOL compared to NEUTRAL (3.7 ± 2.8, p = 0.042; 28.1 ± 12.2.1%, p = 0.031). During COOL, 2 V% was greater (30.5 ± 10.9%) compared to NEUTRAL (26.2 ± 11.3, p = 0.047). The students' thermal comfort was slightly reduced during COOL compared to NEUTRAL trial. During cold season, a better cognitive performance was obtained in a cooler indoor setting enabling therefore energy saving too.

Higher education and science popularization: Can they achieve coordinated growth?

This study aims to explore whether higher education and science popularization can achieve coordinated growth with temporal and spatial characteristics. Selecting the provincial regions of the Yangtze River Economic Belt in China as cases with data from the national statistics administrations (such as China Statistical Yearbook), this study uses entropy weight analysis, TOPSIS, GM(1,1) gray prediction methods and coupling coordination degree model to evaluate the coordinated growth status. The key findings are: (1) the annual budget per student, and the number of science and technology museums affect both systems more obviously; (2) the overall performances of science popularization fluctuate more obviously than those of higher education; (3) the coordinated growth performances of the two systems in most regions remain mild fluctuations and keep relatively stable coordinated status, however, temporal and spatial variation tendencies do exist among regions. Therefore, corresponding countermeasures should be implemented: generally, national authority needs to involve in coordination activities among regions; the regions with satisfactory coordinated growth performances need more creative approaches to maintain the coordinated growth interactions; the regions at the transitioning status need to prevent the grade decline and upgrade the performances; the regions with lagging performances need to stop the decline and reduce the gaps with others. The novelties include analyzing the coordinated growth interaction mechanism between the two, selecting indices to assess the abstract interaction mechanism precisely, proposing suggestions based on temporal and spatial comparisons of the coordinated growth performances, etc.

Classrooms' indoor environmental conditions affecting the academic achievement of students and teachers in higher education: A systematic literature review

This study reports the outcomes of a systematic literature review, which aims to determine the influence of four indoor environmental parameters - indoor air, thermal, acoustic, and lighting conditions -on the quality of teaching and learning and on students' academic achievement in schools for higher education, defined as education at a college or university. By applying the Cochrane Collaboration Method, relevant scientific evidence was identified by systematically searching in multiple databases. After the screening process, 21 publications of high relevance and quality were included. The collected evidence showed that the indoor environmental quality (IEQ) can contribute positively to the quality of learning and short-term academic performance of students. However, the influence of all parameters on the quality of teaching and the long-term academic performance could not be determined yet. Students perform at their best in different IEQ conditions, and these conditions are task-dependent, suggesting that classrooms which provide multiple IEQ classroom conditions facilitate different learning tasks optimally. In addition, the presented evidence illuminates how to examine the influence of the IEQ on users. Finally, this information supports decision-makers in facility management and building systems engineering to improve the IEQ, and by doing so, allow teachers and students to perform optimally.

Perceived air quality and cognitive performance decrease at moderately raised indoor temperatures even when clothed for comfort

This study investigated whether adjusting clothing to remain in neutral thermal comfort at moderately elevated temperature is capable of avoiding negative effects on perceived acute subclinical health symptoms, comfort, and cognitive performance. Two temperatures were examined: 23°C and 27°C. Twelve subjects were able to remain thermally comfortable at both temperatures by adjusting their clothing. They rated the physical environment, their comfort, the intensity of acute subclinical health symptoms, and their mental load, and they performed a number of cognitive tasks. Their physiological reactions were monitored. Their performance of several tasks was significantly worse at 27°C, and they reported increased mental load at this temperature. Skin temperature and humidity and respiration rate were higher, while blood oxygen saturation (SpO2) and pNN50 were lower at this temperature, the latter indicating increased stress. It is inferred that the observed physiological responses were mainly responsible for the negative effects on performance, as the subjects did not indicate any increased intensity of acute subclinical health symptoms although perceived air quality was worse at the higher temperature. The present results suggest that moderately elevated temperatures should be avoided even if thermal comfort can be achieved, as it may lead to reduced performance.

Productivity and physiological responses during exposure to varying air temperatures and clothing conditions

This study assessed the effects of clothing and air temperature combinations on workplace productivity and physiological response. Ten male Japanese subjects were exposed to six combinations of clothing (0.3 clo and 0.9 clo) and air temperature (16°C, 26°C, and 36°C) during which cognitive performance (Bourdon and calculation tests), manual motor performance (finger-tapping test), and physiological responses (heart rate, blood pressure, and skin and oral temperatures) were measured. Both cold exposure and lower clothing levels likely increased the Bourdon test performance. Calculation test performance tended to be affected by exposure to cold or neutral temperatures at the beginning of the test. Cold exposure undermined manual motor performance (especially when combined with fewer clothing items) while heat exposure significantly increased heart rate. Both cold exposure and higher clothing level during heat exposure increased blood pressure. Body temperature, particularly mean skin temperature, increased with higher air temperature and was significantly influenced by clothing insulation during cold exposure. These results provide novel evidence for the effects of clothing and air temperature (particularly cold) on human productivity and physiological responses in humans.

Study of globe temperature relative to air temperature during cognitive activities in information technology laboratories

BACKGROUND

Considering that, environments with information and communication technology innovations, including educational institutions, are providing more interaction among individuals anywhere in the world and contributing to higher learning flexibility, it is necessary to pay extra attention to the radiation dissipated by technological equipment in these environments.

OBJECTIVE

Investigate whether the behavior of the globe temperature (tg) in relation to the air temperature (ta) could affect the performance of students in information technology laboratories (ITLs).

METHODS

The methodological procedures adopted consisted of the following analyses in six institutions: thermal variables - mean radiant temperature (trm) and (tg-ta); students' performance and architectural elements.

RESULTS

ITL G was the ITL with the highest incidence of thermal radiation, thus a mathematical model was proposed for this sample to determine whether (tg - ta) and trm are related to overall student performance (Dt). For each increase of one degree in the difference between the globe temperature and the air temperature (tg-ta), the students' performance in the institution G decreased by approximately 29%.

CONCLUSION

As well as productivity can be altered due to changes in air temperature in air-conditioned teaching environments, in this specific case, if tg> >ta, possibly the thermal radiation may interfere with the performance of the people present in the environment technological innovations of communication and information.

The short-term effects of outdoor temperature on blood pressure among children and adolescents: finding from a large sample cross-sectional study in Suzhou, China

Although several studies have demonstrated a short-term association between outdoor temperature and blood pressure (BP) among various adult groups, evidence among children and adolescents is lacking. One hundred ninety-four thousand one hundred four participants from 2016 Health Promotion Program for Children and Adolescents (HPPCA) were analyzed through generalized linear mixed-effects models to estimate the short-term effects of two outdoor temperature variables (average and minimum temperature) on participants' BP. Decreasing outdoor temperature was associated with significant increases in systolic BP (SBP), diastolic BP (DBP), and prevalence of hypertension during lag 0 through lag 6. Additionally, daily minimum temperature showed a more apparent association with participants' BP. The estimated increases (95% confidence interval) in SBP and DBP at lag 0 were 0.82 (0.72, 0.92) mmHg and 2.28 (2.20, 2.35) mmHg for a 1 °C decrease in daily minimum temperature, while those values were 0.11 (0.10, 0.12) mmHg and 0.25 (0.24, 0.26) mmHg for a 1 °C decrease in daily average temperature, respectively. The effects of temperature on BP were stronger among female, as well as those with young age and low body mass index. It demonstrated that short-term decreases in outdoor temperature were significantly associated with rises in BP among children and adolescents. This founding has some implications for clinical management and research of BP. Meanwhile, public health intervention should be designed to reduce the exposure to cold temperature for protecting children and adolescents' BP.

Students' blood pressure and heart rate while performing cognitive tasks at education institutions in Northern and Northeastern Brazil

BACKGROUND

The use of information and communication technologies improves the versatility of learning environments by broadening the scope of educational practices, allowing students to communicate with other institutions and providing access to information in real time. However, these tools, in addition to environmental characteristics, can increase the internal thermal load, which is directly influenced by the external environment, with a consequent impact on body physiology.

OBJECTIVE

The present study investigated the relationship between air temperature and blood pressure and heart rate among students performing cognitive tasks at computer laboratories in four public universities (three in Northeastern Brazil and one in Northern Brazilian).

METHODS

Thermal conditions and physiological parameters were analysed over three consecutive days, and the participants were subjected to changes in air temperature from 20°C to 33°C. Blood pressure and heart rate were measured before and after testing.

RESULTS

Analyses of the experimental data showed changes in heart rate at high temperatures, with a greater risk of students from Teresina and Manaus institutions presenting heart rates above 100 bpm during cognitive tasks.

CONCLUSIONS

Within the temperature range applied, on the day of the highest temperature, we observed the highest percentage of participants who reported thermal discomfort (63%, 33°C; 58%, 29°C; 38%, 28°C) and a reduction of cognitive performance (15 to 10 points when the air temperature increases from 20 to 33°C).