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Fulltext Extending ‘Kampuchea’ guava shelf-life at 27oC using 1-methylcyclopropene

Phebe, D., Ong, P.T.

International Food Research Journal, 2010;17(1):63-69.
MyJurnal

‘Kampuchea’ guavas were treated with 300, 600 and 900 nL L‾¹ 1-methylcyclopropene (1-MCP) for 0,
3 and 6 h, and stored at 27˚C with 70% relative humidity. The C* values, soluble solids concentration, titratable acidity and pH of these fruits were not affected by both the 1-MCP concentrations and exposure duration while h˚ values and flesh firmness were affected by these treatments. The L* values, vitamin C content and weight loss were affected by the concentrations of 1-MCP, but not by the exposure duration. Less weight loss and disease incidence in fruit treated with 600 and 900 nL L-1 1-MCP. Fruit exposed to 6 h 1-MCP showed lowest disease incidence compared to other exposure duration in 5 days of storage. Treating Kampuchea guava fruit with 600 nL L‾¹ 1-MCP and exposure duration of 6 h was able to retain fruit colour, flesh firmness and delayed disease development for 5 days.

Matched MeSH terms: Humidity
Fulltext Design and Development of a Nearable Wireless System to Control Indoor Air Quality and Indoor Lighting Quality

Salamone F, Belussi L, Danza L, Galanos T, Ghellere M, Meroni I

Sensors (Basel), 2017 May 04;17(5).
PMID: 28471398 DOI: 10.3390/s17051021

The article describes the results of the project "open source smart lamp" aimed at designing and developing a smart object able to manage and control the indoor environmental quality (IEQ) of the built environment. A first version of this smart object, built following a do-it-yourself (DIY) approach using a microcontroller, an integrated temperature and relative humidity sensor, and techniques of additive manufacturing, allows the adjustment of the indoor thermal comfort quality (ICQ), by interacting directly with the air conditioner. As is well known, the IEQ is a holistic concept including indoor air quality (IAQ), indoor lighting quality (ILQ) and acoustic comfort, besides thermal comfort. The upgrade of the smart lamp bridges the gap of the first version of the device providing the possibility of interaction with the air exchange unit and lighting system in order to get an overview of the potential of a nearable device in the management of the IEQ. The upgraded version was tested in a real office equipped with mechanical ventilation and an air conditioning system. This office was occupied by four workers. The experiment is compared with a baseline scenario and the results show how the application of the nearable device effectively optimizes both IAQ and ILQ.

Matched MeSH terms: Humidity
Fulltext Development of a green combat armour from Rame-Kevlar-polyester composite

Zainab Shakir Radif, Aidy Ali, Khalina Abdan

Pertanika Journal of Science & Technology, 2011;19(2):339-348.
MyJurnal

This study was conducted for the development of the green protection garments. For this purpose, laminate composite material was developed from Kevlar 29-ramie-unsaturated polyester resin. The aim of this study was to develop a solid body armour that meets the specific requirements of ballistic resistance. This composite is subjected to high impact loading. The target was shot using gas gun machine that is supported by camera hardware to capture the projectile speed. In order to achieve the goal of the research, several experiments were conducted with the aim to estimate the ballistic limit, maximum energy absorption, composite failure mode, life time rupture, target geometry, and environmental effect. The results of these experiments indicated that the maximum ballistic limit validated at impact speed is in the range of 250 m/s to 656.8 m/s for the second protection level. The targets are improved in term of the impact response with the increase in the relative humidity, i.e. the range of 50% ± 20%, whereas, reduction of resistance results in the increase of temperature. The range of temperatures was between 20oC and 70oC. A limited delamination was generated under multiple shots. Targets geometry plays a major role in increasing the impact response. Hence, the results present a high resistant impact for pairs from the panels with total thickness arrived to 15
mm ± 3 mm. This body armour is one of the most economical armour products, in which common materials are used in its production, particularly to reduce the amount of Kevlar, and this could further lead to a decrease in its production cost. On the other hand, this armour meets the ballistic threats under 623 m/s of 15 mm ± 3 mm target thickness and 837.5 m/s of 25 mm ± 2.mm. Thus, the armour is equivalent to the third level of protective ballistic limits in the National Institute of Justice (NIJ) standards.

Matched MeSH terms: Humidity
Fulltext Field and laboratory observations in Sabah, East Malaysia on the proportion of Anopheles balabecensis balabacensis eggs hatching after holding in a humid atmosphere

Rajapaksa N

Bull World Health Organ, 1971;45(2):263-5.
PMID: 5316626
Matched MeSH terms: Humidity
Fulltext Consequences of rising humidity level on circulatory responses during prolonged intense exercise

Ahmad Munir Che Muhamed, Thompson, Martin William

Movement Health & Exercise, 2012;1(1):11-23.
MyJurnal

The combined metabolic and thermoregulatory demands experienced during exercise in the heat impose an exceptional stress on the circulatory system. To date, much of what is known about circulatory stress during exercise in the heat has focused on primarily dry environment (~ 40% rh)
with limited studies carried in higher humidity (> 60% rh) conditions. This study was designed to investigate the influence of humid condition on circulatory responses during prolonged intense running exercise among elite runners. On separate days, 11 male elite runners ran for 60 minutes at
an intensity of 70% max across three different humidity levels of HH (71% rh), NH (43% rh) and LH (26.2% rh) with the ambient temperature set at 300C. Thermal stress was found to increase during exercise in the HH condition as both Tre and Tsk steadily rise across time. Circulatory stress markedly increased during exercise in higher humidity levels. Heart rate was significantly higher in the HH condition with its level increasing to 92% of HRmax. The upwards drift in HR was significantly higher in HH within the last ten minutes of exercise. Contrary, stroke volume recorded a
steady decline during exercise with a significantly lower SV in the HH as compared with the NH and LH. Results implicate rising humidity level will impose greater circulatory stress during prolonged intense exercise. The consequence from this circulatory stress will result in limited ability for an athlete to sustain his exercise capacity when HR reaches maximal level.

Matched MeSH terms: Humidity
Compositional engineering of VOPcPhO-TiO2nano-composite to reduce the absolute threshold value of humidity sensors

Azmer MI, Aziz F, Ahmad Z, Raza E, Najeeb MA, Fatima N, et al.

Talanta, 2017 Nov 01;174:279-284.
PMID: 28738579 DOI: 10.1016/j.talanta.2017.06.016

This research work demonstrates compositional engineering of an organic-inorganic hybrid nano-composites for modifying absolute threshold of humidity sensors. Vanadyl-2,9,16,23-tetraphenoxy-29H,31H-phthalocyanine (VOPcPhO), an organic semiconductor, doped with Titanium-dioxide nanoparticles (TiO2NPs) has been employed to fabricate humidity sensors. The morphology of the VOPcPhO:TiO2nano-composite films has been analyzed by atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM). The sensors have been examined over a wide range of relative humidity i.e. 20-99% RH. The sensor with TiO2(90nm) shows reduced sensitivity-threshold and improved linearity. The VOPcPhO:TiO2(90nm) nano-composite film is comprised of uniformly distributed voids which makes the surface more favorable for adsorption of moisture content from environment. The VOPcPhO:TiO2nano-composite based sensor demonstrates remarkable improvement in the sensing parameter when equated with VOPcPhO sensors.

Matched MeSH terms: Humidity
Fulltext Indoor air quality: microbe and its relationship toward temperature, relative humidity and carbon dioxide concentration

Shoffian Amin Jaafar, Suhaily Amran, Mohd Norhafsham Maghpor, Ahmad Sayuti Zainal, Nurzuhairah Jamil, Naemah Tajul Arus, et al.

Journal of Occupational Safety and Health, 2015;12(1):73-80.
MyJurnal

Indoor air quality is a term which refers to the air quality in and around buildings and structures, in which it
is related to the health and comfort of those who are in the building. The study aims to identify the relationship
between environmental factors with microbe growth by investigating the concentration of airborne bacteria and
fungi at National Institute of Occupational Safety and Health (NIOSH) and to determine whether indoor bacteria and
fungi concentration were associated with environmental factors such as temperature relative humidity and carbon
dioxide concentration. This research was conducted concurrently with indoor air quality sampling as per requirement
under the Malaysian Code of Practice of Indoor Air Quality (COP IAQ). The COP IAQ requires minimum of one
sample to be taken from each area. If an area consists of a few separated rooms, each room is sampled and measured
independently. Also this approach was used to determine whether there is a difference of indoor bacteria and fungi
in different microenvironments. Results show that there is a significant correlation between humidity and bacteria
concentration and fungi concentration; and between temperature and bacteria concentration. However, there is no
significant correlation between temperature and fungi concentration. This study has also established significant
difference on bacteria concentration and fungi concentration between microenvironments.

Matched MeSH terms: Humidity
Fulltext Indoor plants as a filtration of indoor air pollution: a review

Mohd Mahathir Suhaimi Shamsuri, Leman, A.M.

Journal of Occupational Safety and Health, 2015;12(2):41-48.
MyJurnal

Indoor pollution increasingly becomes a public concern. These concerns are related to energy efficiency in a
building. There are various ways in which it can ensure energy conservation can be achieved, including superinsulation
and reduced fresh air exchange. As a result, indoor air becomes stagnant and odours, thereafter contaminants of air will
accumulate and will certainly disrupt human health. It is quite difficult to make people comfortable in a building with
consumption of energy-saving and human health guaranteed. Indoor plants are one of the alternative solutions that
have been studied since the last three decades. This paper intends to review the abilities of indoor plants to purify air,
and the ways used by previous researchers to prove that indoor plants can treat the air. In general, it can be stated that
indoor plants are able to absorb various types of volatile organic compounds (VOCs). An advantage of indoor plants
to cure air from carcinogen gas is greatly needed for human health. Therefore, studies on indoor plants to neutralize
the air are gaining attention. Enclosed space or chamber is often used by researchers to test the ability of indoor plants
absorb gaseous toxins in their study; because it is easy to handle and can quickly determine the absorption rate. In the
other hand, environmental factors such as temperature, humidity, and light are important to be taken into consideration
during the study. As a conclusion, it can be stated that the existence of indoor plants in a building is very reasonable,
because it can give positive impacts on human health and the total energy consumption.

Matched MeSH terms: Humidity
Feedforward backpropagation, Genetic Algorithm approaches for predicting reference evapotranspiration

Shafika Sultan Abdullah, M.A. Malek, Namiq Sultan Abdullah, A. Mustapha

Sains Malaysiana, 2015;44:1053-1059.

Water scarcity is a global concern, as the demand for water is increasing tremendously and poor management of water resources will accelerates dramatically the depletion of available water. The precise prediction of evapotranspiration (ET), that consumes almost 100% of the supplied irrigation water, is one of the goals that should be adopted in order to avoid more squandering of water especially in arid and semiarid regions. The capabilities of feedforward backpropagation neural networks (FFBP) in predicting reference evapotranspiration (ET0) are evaluated in this paper in comparison with the empirical FAO Penman-Monteith (P-M) equation, later a model of FFBP+Genetic Algorithm (GA) is implemented for the same evaluation purpose. The study location is the main station in Iraq, namely Baghdad Station. Records of weather variables from the related meteorological station, including monthly mean records of maximum air temperature (Tmax), minimum air temperature (Tmin), sunshine hours (Rn), relative humidity (Rh) and wind speed (U2), from the related meteorological station are used in the prediction of ET0 values. The performance of both simulation models were evaluated using statistical coefficients such as the root of mean squared error (RMSE), mean absolute error (MAE) and coefficient of determination (R2). The results of both models are promising, however the hybrid model shows higher efficiency in predicting ET0 and could be recommended for modeling of ET0 in arid and semiarid regions.

Matched MeSH terms: Humidity
Fulltext Variability on particulate matter and meteorology dataset during the hazy period in eastern region of Peninsular Malaysia

Ku Yusof KMK, Ismail SS, Azid A, Sani MSA, Isa NM, Mohamat Zawawi MZ

Data Brief, 2020 Apr;29:105210.
PMID: 32071985 DOI: 10.1016/j.dib.2020.105210

This paper provides detail on sequence analysis of hazy days based on eight monitoring stations from three states (Kelantan, Terengganu and Pahang) in the eastern region of Peninsular Malaysia. The dataset comprises of 1502 daily mean hazy days that had been measured for a decade. The meteorology data namely wind speed, wind direction, air temperature, relative humidity and particulate matter (PM10) were used to comprehend the variability, and the relationship existed amongst variables. The final dataset consists of a summary descriptive analysis and a boxplot, where all five variables were involved, including the minimum, maximum, mean, 1st quartile, median, 3rd quartile and standard deviation are presented. Apart from descriptive analysis, the normality test and histogram were performed as well.

Matched MeSH terms: Humidity
Fulltext Amino Anthraquinone: Synthesis, Characterization, and Its Application as an Active Material in Environmental Sensors

Ali S, Tahir M, Mehboob N, Wahab F, J Langford S, Mohd Said S, et al.

Materials (Basel), 2020 Feb 21;13(4).
PMID: 32098037 DOI: 10.3390/ma13040960

This work reports synthesis, thin film characterizations, and study of an organic semiconductor 2-aminoanthraquinone (AAq) for humidity and temperature sensing applications. The morphological and phase studies of AAq thin films are carried out by scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray diffraction (XRD) analysis. To study the sensing properties of AAq, a surface type Au/AAq/Au sensor is fabricated by thermally depositing a 60 nm layer of AAq at a pressure of ~10-5 mbar on a pre-patterned gold (Au) electrodes with inter-electrode gap of 45 µm. To measure sensing capability of the Au/AAq/Au device, the variations in its capacitance and resistance are studied as a function of humidity and temperature. The Au/AAq/Au device measures and exhibits a linear change in capacitance and resistance when relative humidity (%RH) and temperature are varied. The AAq is a hydrophobic material which makes it one of the best candidates to be used as an active material in humidity sensors; on the other hand, its high melting point (575 K) is another appealing property that enables it for its potential applications in temperature sensors.

Matched MeSH terms: Humidity
Fulltext Pesticide application, dermal exposure risk and factors influenced distribution on different body parts among agriculture workers

Nurulain M, Syed Ismail S, Emilia Z, Vivien H

Malaysian Journal of Public Health Medicine, 2017;17 Special(1):123-132.

Agriculture sector accounts significant numbers of injuries and fatalities in the workplace particularly related to pesticide management. Among three main pathways of pesticide exposure, dermal contact is the most common route, which exposure usually occurs during pesticide mixing/loading, application, harvesting and other farming activities. This review aims to present and discuss several vital components of pesticide dermal exposure among agriculture workers, as well as pesticide application in agriculture sector in Malaysia involving different commodity agriculture sub-sectors. Pesticide exposure was discussed from perspective of three pesticide management activities (i.e. preparation, application and cleaning) that contribute to the risk of exposure through three routes (i.e. emission, deposition, transfer). Moreover, this paper also discussed pesticide dermal exposure risk assessment methods which can be defined into exposure assessment and effect assessment. The exposure rate was affected by various factors such as application equipment, application rate and duration, type of pesticide formulation, pesticide management stage, usage of personal protective equipment, training and aptitude of the applicator as well as environmental factors (i.e. temperature, humidity, wind speed and direction). The factors mention earlier have been used to explain the exposure distribution over different parts of the body and support the fact that pesticide type was not a major factor in total exposure.

Matched MeSH terms: Humidity
Fulltext Data on Indoor Air Quality (IAQ) in kindergartens with different surrounding activities

Abdullah S, Abd Hamid FF, Ismail M, Ahmed AN, Wan Mansor WN

Data Brief, 2019 Aug;25:103969.
PMID: 31198825 DOI: 10.1016/j.dib.2019.103969

The aim of the measurement of this data is to evaluate the Indoor Air Quality (IAQ) in terms of chemical and physical parameters. Data were collected at three different kindergartens having different surrounding activities (industrial, institutional, residential area). The chemical parameters measured were respirable suspended particulates of PM10, PM2.5, PM1, carbon monoxide and carbon dioxide, and the concentrations are within the acceptable limit. Physical parameters of wind speed are within the standard, while temperature and relative humidity exceeded the acceptable limit. A strong correlation was found between the chemical IAQ parameters with thermal comfort parameters (temperature and relative humidity). The concentration of IAQ pollutants is higher in order of residential > institutional > industrial.

Matched MeSH terms: Humidity
Fulltext A Fault Tolerant Surveillance System for Fire Detection and Prevention Using LoRaWAN in Smart Buildings

Safi A, Ahmad Z, Jehangiri AI, Latip R, Zaman SKU, Khan MA, et al.

Sensors (Basel), 2022 Nov 01;22(21).
PMID: 36366109 DOI: 10.3390/s22218411

In recent years, fire detection technologies have helped safeguard lives and property from hazards. Early fire warning methods, such as smoke or gas sensors, are ineffectual. Many fires have caused deaths and property damage. IoT is a fast-growing technology. It contains equipment, buildings, electrical systems, vehicles, and everyday things with computing and sensing capabilities. These objects can be managed and monitored remotely as they are connected to the Internet. In the Internet of Things concept, low-power devices like sensors and controllers are linked together using the concept of Low Power Wide Area Network (LPWAN). Long Range Wide Area Network (LoRaWAN) is an LPWAN product used on the Internet of Things (IoT). It is well suited for networks of things connected to the Internet, where terminals send a minute amount of sensor data over large distances, providing the end terminals with battery lifetimes of years. In this article, we design and implement a LoRaWAN-based system for smart building fire detection and prevention, not reliant upon Wireless Fidelity (Wi-Fi) connection. A LoRa node with a combination of sensors can detect smoke, gas, Liquefied Petroleum Gas (LPG), propane, methane, hydrogen, alcohol, temperature, and humidity. We developed the system in a real-world environment utilizing Wi-Fi Lora 32 boards. The performance is evaluated considering the response time and overall network delay. The tests are carried out in different lengths (0-600 m) and heights above the ground (0-2 m) in an open environment and indoor (1st Floor-3rd floor) environment. We observed that the proposed system outperformed in sensing and data transfer from sensing nodes to the controller boards.

Matched MeSH terms: Humidity
Relative Humidity Cycling: Implications on the Stability of Moisture-Sensitive Drugs in Solid Pharmaceutical Products

Veronica N, Heng PWS, Liew CV

Mol Pharm, 2023 Feb 06;20(2):1072-1085.
PMID: 36480246 DOI: 10.1021/acs.molpharmaceut.2c00812

The stability of a moisture-sensitive drug in tablet formulations depends particularly on the environment's relative humidity (RH) and the products' prior exposure to moisture. This study was designed to understand drug stability in relation to the moisture interaction of the excipients, moisture history of the tablets, and RH of the environment. The stability study was performed on tablets containing acetylsalicylic acid (ASA), formulated with common pharmaceutical excipients like native maize starch, microcrystalline cellulose (MCC), partially pregelatinized maize starch (PGS), dicalcium phosphate dihydrate (DCP), lactose, and mannitol. The tablets were subjected to storage conditions with RH cycling alternating between 53% and 75%. Results were also compared to tablets stored at a constant RH of 53% or 75%. The excipients demonstrated marked differences in their interactions with moisture. They could be broadly grouped as excipients with RH-dependent moisture content (native maize starch, MCC, and PGS) and RH-independent moisture content (DCP, lactose, and mannitol). As each excipient interacted differently with moisture, degradation of ASA in the tablets depended on the excipients' ability to modulate the moisture availability for degradation. The lowest ASA degradation was observed in tablets formulated with low moisture content water-soluble excipients, such as lactose and mannitol. The impact of RH cycling on ASA stability was apparent in tablets containing native maize starch, MCC, PGS, or DCP. These findings suggested that the choice of excipients influences the effect of moisture history on drug stability. The results from studies investigating moisture interaction of excipients and drug stability are valuable to understanding the inter-relationship between excipients, moisture history, and drug stability.

Matched MeSH terms: Humidity
Effect of asymmetrical street aspect ratios on microclimates in hot, humid regions

Qaid A, Ossen DR

Int J Biometeorol, 2015 Jun;59(6):657-77.
PMID: 25108376 DOI: 10.1007/s00484-014-0878-5

Asymmetrical street aspect ratios, i.e. different height-to-width (H1/W-H2/W) ratios, have not received much attention in the study of urban climates. Putrajaya Boulevard (northeast to southwest orientation) in Malaysia was selected to study the influence of six asymmetrical aspect ratio scenarios on the street microclimate using the Envi-met three-dimensional microclimate model (V3.1 Beta). Putrajaya Boulevard suffers from high surface and air temperature during the day due to the orientation, the low aspect ratio and the wide sky view factor. These issues are a common dilemma in many boulevards. Further, low and high symmetrical streets are incompatible with tropical regions as they offer conflicting properties during the day and at night. These scenarios are examined, therefore, to find asymmetrical streets which are able to reduce the impact of the day microclimate on boulevards, and as an alternative strategy fulfilling tropical day and night climatic conditions. Asymmetrical streets are better than low symmetrical streets in enhancing wind flow and blocking solar radiation, when tall buildings confront winds direction or solar altitudes. Therefore, mitigating heat islands or improving microclimates in asymmetrical streets based on tall buildings position which captures wind or caste shades. In northeast to southwest direction, aspect ratios of 0.8-2 reduce the morning microclimate and night heat islands yet the negative effects during the day are greater than the positive effects in the night. An aspect ratio of 2-0.8 reduces the temperature of surfaces by 10 to 14 °C and the air by 4.7 °C, recommended for enhancing boulevard microclimates and mitigating tropical heat islands.

Matched MeSH terms: Humidity*
Mouth rinsing improves cycling endurance performance during Ramadan fasting in a hot humid environment

Che Muhamed AM, Mohamed NG, Ismail N, Aziz AR, Singh R

Appl Physiol Nutr Metab, 2014 Apr;39(4):458-64.
PMID: 24669987 DOI: 10.1139/apnm-2013-0276

This study examined the effect of mouth rinsing during endurance cycling in a hot humid environment (32 °C and 75% relative humidity) on athletes in the Ramadan fasted state. Nine trained adolescent male cyclists completed 3 trials that consisted of a carbohydrate mouth-rinse (CMR), a placebo mouth-rinse (PMR), and a no-rinse (NOR) trial during the last 2 weeks of Ramadan. Each trial consisted of a preloading cycle at 65% peak rate of oxygen consumption for 30 min followed by a 10-km time trial (TT10 km) under hot humid condition. During the CMR and PMR trials, each cyclist rinsed his mouth with 25 mL of the solution for 5 s before expectorating the solution pre-exercise, after 5, 15, and 25 min of the preloading cycle, and 15 s prior to the start of TT10 km. Time to complete the TT10 km was significantly faster in the CMR and PMR trials compared with the NOR trial (12.9 ± 1.7 and 12.6 ± 1.7 vs. 16.8 ± 1.6 min, respectively; p < 0.017). Ratings of perceived exertion taken at the end of the TT10 km was lower in both CMR and PMR trials compared with the NOR trial, although the difference was significant only between CMR and NOR (p < 0.05). In conclusion, mouth rinsing with either carbohydrate or placebo solution provided ergogenic benefits compared with a no-rinse condition on TT10 km performance in acute Ramadan fasted subjects during endurance cycling in a heat stress environment.

Matched MeSH terms: Humidity*
Sweating distribution and active sweat glands on the scalp of young males in hot-dry and hot-humid environments

Jung D, Kim YB, Lee JB, Muhamed AMC, Lee JY

Eur J Appl Physiol, 2018 Dec;118(12):2655-2667.
PMID: 30209544 DOI: 10.1007/s00421-018-3988-7

PURPOSE: We investigated the effects of humidity on regional sweating secretion and active sweat gland density on the scalp during passive heating in hot environments.
METHODS: Eight male subjects shaved their heads prior to expose to dry (30%RH; H30%) and humid (85%RH; H85%) conditions at an air temperature of 32 °C. Total sweat rate, local sweat rates (frontal, vertex, temporal, and occipital regions), active sweat glands on the scalp (2 frontal, 2 parietal, 2 temporal, 1 occipital, and 1 vertex), and rectal and skin temperatures were measured during leg immersion in 42 °C water for 60 min.
RESULTS: (1) Total sweat rates were greater for H30% (179.4 ± 35.6 g h-1) than for H85% (148.1 ± 27.2 g h-1) (P

Matched MeSH terms: Humidity*
Differences in dry-bulb temperature do not influence moderate-duration exercise performance in warm environments when vapor pressure is equivalent

Lei TH, Schlader ZJ, Che Muhamed AM, Zheng H, Stannard SR, Kondo N, et al.

Eur J Appl Physiol, 2020 Apr;120(4):841-852.
PMID: 32072226 DOI: 10.1007/s00421-020-04322-8

PURPOSE: Recent studies have determined that ambient humidity plays a more important role in aerobic performance than dry-bulb temperature does in warm environments; however, no studies have kept humidity constant and independently manipulated temperature. Therefore, the purpose of this study was to determine the contribution of dry-bulb temperature, when vapor pressure was matched, on the thermoregulatory, perceptual and performance responses to a 30-min cycling work trial.
METHODS: Fourteen trained male cyclists (age: 32 ± 12 year; height: 178 ± 6 cm; mass: 76 ± 9 kg; [Formula: see text]: 59 ± 9 mL kg-1 min-1; body surface area: 1.93 ± 0.12 m2; peak power output: 393 ± 53 W) volunteered, and underwent 1 exercise bout in moderate heat (MOD: 34.9 ± 0.2 °C, 50.1 ± 1.1% relative humidity) and 1 in mild heat (MILD: 29.2 ± 0.2 °C, 69.4 ± 0.9% relative humidity) matched for vapor pressure (2.8 ± 0.1 kPa), with trials counterbalanced.
RESULTS: Despite a higher weighted mean skin temperature during MOD (36.3 ± 0.5 vs. 34.5 ± 0.6 °C, p

Matched MeSH terms: Humidity*
Thermoplastic starch/beeswax blend: Characterization on thermal mechanical and moisture absorption properties

Diyana ZN, Jumaidin R, Selamat MZ, Suan MSM

Int J Biol Macromol, 2021 Nov 01;190:224-232.
PMID: 34481857 DOI: 10.1016/j.ijbiomac.2021.08.201

Cassava starch has acquired many attentions owing to its ability to be developed as thermoplastic cassava starch (TPCS) where it can be obtained in low cost, making it to be one of alternatives to substitute petroleum-based plastic. An attempt was made to investigate the thermal, mechanical and moisture absorption properties of thermoplastic cassava starch blending with beeswax (TPCS-BW) fabricated using hot moulding compression method in the range of beeswax loading from 0, 2.5, 5 to 10 wt%. Addition of beeswax has significantly reduced tensile strength, elongation and flexural strength while improving tensile modulus and flexural modulus until 5 wt% beeswax. Incorporation of 10 wt% beeswax has successfully produced the lowest value of moisture absorption and water solubility among the bio-composite which might be attributed to the beeswax's hydrophobic properties in improving water barrier of the TPCS-BW bio-composite. Furthermore, the addition of beeswax resulted in the appearance of irregular and rough fractured surface. Meanwhile, fourier transform infrared (FT-IR) spectroscopy presented that incorporation of beeswax in the mixture has considerably improve hydrogen bonding of blends indicating good interaction between starch and beeswax. Hence, beeswax with an appropriate loading value able to improve the functional properties of TPCS-BW bio-composite.

Matched MeSH terms: Humidity*

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