“The Menthol One Is More Friendly”: Young Singaporeans’ Perspectives on Flavored Cigarettes

Over half of the cigarettes sold in Singapore contain added flavors such as menthol. We conducted nine focus group discussions (n = 46) with young (age 20-25) current smokers in Singapore to understand the role of flavors in smoking initiation. We found that flavors triggered the curiosity to experiment with tobacco and e-cigarette products and played an important role in the formation of early cigarette preferences. Menthol-flavored cigarettes were the most appealing to participants due to their smoothness and cooling sensation, described as pleasant against Singapore’s hot and humid climate. While some participants believed that flavored and nonflavored cigarettes were equally harmful, others believed that flavored variants had a lower nicotine content and were therefore less harmful, or that the added chemicals in flavored cigarettes could result in higher toxicant exposures. Thus, among young people in Singapore, flavors appear to play an important role in smoking initiation and there appear to be various misperceptions regarding their harmfulness.

Thermal performance of a non–segmented and segmented tall atrium in hot and humid climate

The study was designed to quantify the thermal conditions in tall atria in office buildings to serve as a starting point towards understanding their performance. The simulation study of a non-segmented and segmented atrium of 250 m height reveals indoor air temperature, wind velocity contours and wind pressure coefficients at various heights of each atrium type. In a hot and humid climate like that of Singapore, the internal temperatures within each atrium stack remain constant at 27°C. However, the wind velocity in the non-segmented atrium (of 0.5 - 0.7 m/s) is lower than acceptable (0.9 m/s) for human occupancy. Adding segments and a larger inlet to the atrium solves the problem of low wind velocity without increasing the effective ambient temperature within the atrium stack. Additionally, the segmented atrium offers the advantage of displaying lower buoyancy forces by lowering the pressure differential within a tall stack thereby providing better comfort conditions.

Temperate Air Breathing Increases Cycling Performance in Hot and Humid Climate Environment

Practicing physical activity in a hot and humid climate (HHC) is becoming increasingly common due to anthropogenic climate change and the growing number of international sports events held in warm countries. The aim of this study was to understand the physiological and psychological effects of breathing two air temperatures during cycling exercise in HHC. Ten male athletes performed two sessions of exercise in HHC (T°: 32.0 ± 0.5 °C, relative humidity: 78.6 ± 0.7%) during which they breathed hot air (HA, 33.2 ± 0.06 °C) or temperate air (TA, 22.6 ± 0.1 °C). Each session was composed of 30 min of pre-fatigue cycling at constant intensity, followed by a 10 min self-regulated performance. During pre-fatigue, TA induced a better feeling score and a lower rating of perceived effort (respectively, +0.9 ± 0.2, p < 0.05; 1.13 ± 0.21; p < 0.05) with no changes in physiological parameters. During performance, oxygen consumption and mechanical workload were increased by TA (respectively, +0.23 ± 0.1 L min−1, p < 0.05 and +19.2 ± 6.1 W, p < 0.01), whereas no significant differences were observed for psychological parameters. Reducing the breathed air temperature decreased the discomfort induced by HHC during exercise and increased the performance capacity during self-regulated exercise. Thus, breathed air temperature perception is linked to the hardship of training sessions and directly contributes to the performance decrease in HHC.

Thermal Comfort Performance of Naturally Ventilated Royal Malaysian Police (RMP) Lockup in Hot and Humid Climate of Malaysia

Thermal comfort performance of three vacant naturally ventilated Royal Malaysia Police (RMP) case study lockups (LK1 in Penang, LK2 in Melaka & LK3 in Kuala Lumpur) was measured during monsoon change period from Northeast Monsoon to Southeast Monsoon. According to NGO’s report and previous studies, the lockups condition is very poor and hot which contribute to discomfort among detainees. The objectives of the study are to investigate thermal comfort performance of the lockups based on four environmental parameters (Ta, Tr, Va, & RH) through physical measurement, to predict thermal comfort performance based on operative temperature (To) and neutral operative temperature (Tneutop), and to compare the results with thermal comfort criteria recommended by ASHRAE 55 standard and previous thermal comfort studies in hot and humid climate. The results show that To and Tneutop reading of LK1 is exceeding the maximum range recommended by ASHRAE 55 and previous studies by 2% to 8% (To) and 1% (Tneutop) which categorizing LK1 condition as hot. This is mostly due to high hot airflow brought through an ineffective window opening. The results will be used as reference for improvement towards some aspects such as window opening, building finishes materials, space volume and building orientation in future lockup design.

Thermal Comfort Index for Lactating Water Buffaloes under Hot and Humid Climate

Heat stress results in serious performance losses and adversely affects animal health and welfare under various production systems. This study was conducted to develop a thermal comfort model for lactating buffaloes under hot and humid climate. Twenty Nili-Ravi buffaloes were randomly enrolled for this one-year study. Physiological parameters including rectal temperature (RT), respiratory rate (RR), and body surface temperature (BST) and environmental variables such as wet bulb temperature (WBT), dew point temperature (DPT), and black globe temperature (BGT) were recorded twice a week on each Tuesday and Thursday (n = 1602 and 1560, respectively) at 8:00 am and 2:30 pm. Moreover, ambient temperature (AT, °C) and relative humidity (RH, %), at an interval of every 30 min were recorded. We used a typical correlation analysis to build the index models for thermal comfort. The results revealed that AT positively correlated with BGT, WBT, DPT, BST, RT, and RR, while RH negatively correlated with RT. Moreover, a physiological index model consisting of BST, RT and RR (P1 = 0.578 × BST + 0.047 × RT + 0.429 × RR) and an environmental index model (E1 = 0.881 × AT + 0.194 × RH + 0.455 × BGT − 0.347 × WBT + 0.032 × DPT) proved to be a more accurate index as a pair to reveal the state of thermal comfort in lactating buffaloes. Moreover, these models correlated well with physiological variables, indicating that this this pair of index models can be used to effectively evaluate the thermal comfort in buffaloes.

Optimization of Architectural Form for Thermal Comfort in Naturally Ventilated Gymnasium at Hot and Humid Climate by Orthogonal Experiment

As the gymnasiums in subtropical region with hot and humid climate are naturally ventilated during non-competition periods, occupants exercising indoors often feel uncomfortable, especially in summer. In order to provide thermally comfortable and healthy environment for the occupants, the design on architectural form is found to be an effective solution on improving indoor thermal comfort of naturally ventilated gymnasiums. Therefore, a new perspective regarding optimization of naturally ventilated gymnasiums is proposed in the aspect of the architectural form. This paper presents the optimization of architectural form in naturally ventilated gymnasiums in which simulation and orthogonal experiment methods are combined. Through numerical simulation with FlowDesigner software, the significance of architectural form affecting indoor thermal comfort has been given, and the optimal architectural forms of naturally ventilated gymnasium are determined. The results show that the roof insulation type is the most significant factor influencing indoor thermal comfort; thus, it should be considered primarily in optimization. Moreover, the range analysis and variance analysis reveal the rankings of the factors for the gymnasium thermal comfort. In addition, it is demonstrated that the optimal gymnasium model, when compared with the initial gymnasium model, has a satisfactory effect on improving the indoor thermal comfort, as the average value of Predicted Thermal Sensation (PTS) in August decreased from 1.11 (Slightly hot) to 0.86 (Comfortable). This study provides a new insight for the designers in optimizing the architectural form of gymnasiums for achieving the indoor thermal comfort at hot and humid climate.