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The effect of filler content and processing variables on dimensional accuracy of experimental composite inlay material

Razak AA, Harrison A

J Prosthet Dent, 1997 Apr;77(4):353-8.
PMID: 9104710

Dimensional accuracy of a composite inlay restoration is important to ensure an accurate fit and to minimize cementation stresses.

Matched MeSH terms: Hot Temperature
Effect of tropical outdoor weathering on the surface roughness and mechanical properties of maxillofacial silicones

Rahman AM, Jamayet NB, Nizami MMUI, Johari Y, Husein A, Alam MK

J Prosthet Dent, 2021 Jan 17.
PMID: 33472753 DOI: 10.1016/j.prosdent.2020.07.026

STATEMENT OF PROBLEM: The climate of tropical Southeast Asia includes high humidity and ultraviolet radiation that reduce the lifespan of silicone prostheses by inducing changes in their mechanical properties and color stability. Studies on the surface roughness (SR) and mechanical properties of different silicone elastomers (SEs) subjected to the natural tropical weather of Southeast Asia are lacking.
PURPOSE: The purpose of this in vitro study was to evaluate the SR, tensile strength (TS), and percentage elongation (% E) of different SEs subjected to outdoor weathering in the Malaysian climate.
MATERIAL AND METHODS: Type-II dumbbell-shaped specimens (N-120) (nonweathered=15, weathered=15) were made from 3 room-temperature vulcanized (A-2000, A-2006, and A-103) and 1 heat-temperature vulcanized (M-511) silicone (Factor II). For 6 months, weathered specimens were subjected to outdoor weathering inside a custom exposure rack. Simultaneously, the nonweathered specimens were kept in a dehumidifier. Subsequently, the SR was measured with a profilometer; TS and % E were measured by using a universal testing machine. Two-way ANOVA was used to compare the means of the tested properties of the nonweathered and weathered specimens, and pairwise comparison was carried out between the silicones (α=.05).
RESULTS: After outdoor weathering, the SR, TS, and % E were adversely affected by weathering in the Malaysian environment. Among the silicone materials, A-2000 showed the least TS changes (2.51 MPa), while A-2006 demonstrated significant changes in percentage elongation after outdoor weathering (266.5%). M-511 exhibited the highest mean value (2.50 μm) for SR changes. In addition, A-103 SE showed statistically significant differences in most pairwise comparisons for all 3 dependent variables.
CONCLUSIONS: Based on the evaluation of mechanical properties, A-103 can be suggested as a suitable silicone for maxillofacial prostheses fabricated for tropical climates. However, A-2000 can be a suitable alternative, although significant changes to surface roughness were detected after outdoor weathering.

Matched MeSH terms: Hot Temperature
Wettability of 3 different artificial saliva substitutes on heat-polymerized acrylic resin

Jaiswal N, Patil PG, Gangurde A, Parkhedkar RD

J Prosthet Dent, 2019 Mar;121(3):517-522.
PMID: 30391058 DOI: 10.1016/j.prosdent.2018.03.037

STATEMENT OF PROBLEM: The prosthodontic problems faced by a patient with xerostomia are of great concern. To aid in retention, artificial saliva substitutes should exhibit good wettability on the denture base.
PURPOSE: The purpose of this in vitro study was to evaluate the wettability of 3 different artificial saliva substitutes on heat-polymerized acrylic resin and to compare these properties with natural saliva and distilled water.
MATERIAL AND METHODS: A total of 150 heat-polymerized acrylic resin specimens were prepared with 25×15×2 mm dimensions. The specimens were divided into 5 groups (n=30): human saliva, distilled water, Aqwet, Mouth Kote, and Stoppers 4. The advancing and receding contact angle values were measured by using a goniometer, and the contact angle hysteresis and equilibrium angle were calculated. One-way ANOVA and the Bonferroni multiple comparisons test were performed to determine the difference between contact angle values among the groups (α=.05).
RESULTS: The means of the 5 groups differed significantly (P

Matched MeSH terms: Hot Temperature*
Is microbial adhesion affected by the build orientation of a 3-dimensionally printed denture base resin?

Yacob N, Ahmad NA, Safii SH, Yunus N, Abdul Razak F

J Prosthet Dent, 2023 Jul;130(1):131.e1-131.e7.
PMID: 37210224 DOI: 10.1016/j.prosdent.2023.04.017

STATEMENT OF PROBLEM: How the build orientation of a 3-dimensionally (3D) printed denture affects microbial adhesion is unclear.
PURPOSE: The purpose of this in vitro study was to compare the adherence of Streptococcus spp. and Candida spp. on 3D-printed denture bases prepared at different build orientations with conventional heat-polymerized resin.
MATERIAL AND METHODS: Resin specimens (n=5) with standardized 28.3 mm2 surface area were 3D printed at 0 and 60 degrees, and heat-polymerized (3DP-0, 3DP-60, and HP, respectively). The specimens were placed in a Nordini artificial mouth (NAM) model and exposed to 2 mL of clarified whole saliva to create a pellicle-coated substratum. Suspensions of Streptococcus mitis and Streptococcus sanguinis, Candida albicans and Candida glabrata, and a mixed species, each at 108 cfu/mL were pumped separately into the model for 24 hours to promote microbial adhesion. The resin specimens were then removed, placed in fresh media, and sonicated to dislodge attached microbes. Each suspension (100 μL) was aliquoted and spread on agar plates for colony counting. The resin specimens were also examined under a scanning electron microscope. The interaction between types of specimen and groups of microbes was examined with 2-way ANOVA and then further analysis with Tukey honest significant test and Kruskal-Wallis post hoc tests (α=.05).
RESULTS: A significant interaction was observed between the 3DP-0, 3DP-60, and HP specimen types and the groups of microbes adhering to the corresponding denture resin specimens (P

Matched MeSH terms: Hot Temperature
Immunochemical characterization of edible bird's nest allergens

Goh DL, Chua KY, Chew FT, Liang RC, Seow TK, Ou KL, et al.

J Allergy Clin Immunol, 2001 Jun;107(6):1082-7.
PMID: 11398089

BACKGROUND: We have previously described anaphylaxis induced by edible bird's nest (BN) and demonstrated that this condition is IgE mediated.
OBJECTIVES: This study aimed at describing the immunochemical properties of the BN allergens. Comparative studies between 3 commercially available sources (according to the country of origin) of BN were also made.
METHODS: Crude extracts of commercially available processed BN from Sarawak (Malaysia), Thailand, and Indonesia and fresh unprocessed BN from the caves of Sarawak were obtained by means of aqueous extraction. Specific IgE toward these sources were determined by using fluorescence allergosorbent tests (FASTs). Cross-reactivity studies between the 3 sources of commercially available processed BN were carried out by means of FAST inhibition. Immunochemical characterization by means of IgE immunoblot, periodate treatment, and heat stability studies were carried out on fresh unprocessed BN from Sarawak.
RESULTS: Serum from allergic patients showed differences in IgE binding to the 3 sources of commercially available BN, with the highest levels of specific IgE recorded with the Sarawak source (P

Matched MeSH terms: Hot Temperature
Effects of acute supplementation of Panax ginseng on endurance running in a hot & humid environment

Ping FW, Keong CC, Bandyopadhyay A

Indian J Med Res, 2011 Jan;133:96-102.
PMID: 21321426

Athletes in Malaysia need to perform in a hot and humid environment due to the climatic nature of the country. Chronic supplementation of Panax ginseng (PG) (a deciduous perennial plant belonging to the Araliaceae family) enhances physical performance. As the ergogenic effect of acute supplementation of PG on endurance performance has not been explored in the Malaysian population especially in a hot and humid condition this study was taken up.

Matched MeSH terms: Hot Temperature*
Fulltext Temperature transcends partner specificity in the symbiosis establishment of a cnidarian

Herrera M, Klein SG, Campana S, Chen JE, Prasanna A, Duarte CM, et al.

ISME J, 2021 01;15(1):141-153.
PMID: 32934356 DOI: 10.1038/s41396-020-00768-y

Coral reef research has predominantly focused on the effect of temperature on the breakdown of coral-dinoflagellate symbioses. However, less is known about how increasing temperature affects the establishment of new coral-dinoflagellate associations. Inter-partner specificity and environment-dependent colonization are two constraints proposed to limit the acquisition of more heat tolerant symbionts. Here, we investigated the symbiotic dynamics of various photosymbionts in different host genotypes under "optimal" and elevated temperature conditions. To do this, we inoculated symbiont-free polyps of the sea anemone Exaiptasia pallida originating from Hawaii (H2), North Carolina (CC7), and the Red Sea (RS) with the same mixture of native symbiont strains (Breviolum minutum, Symbiodinium linucheae, S. microadriaticum, and a Breviolum type from the Red Sea) at 25 and 32 °C, and assessed their ITS2 composition, colonization rates, and PSII photochemical efficiency (Fv/Fm). Symbiont communities across thermal conditions differed significantly for all hosts, suggesting that temperature rather than partner specificity had a stronger effect on symbiosis establishment. Overall, we detected higher abundances of more heat resistant Symbiodiniaceae types in the 32 °C treatments. Our data further showed that PSII photophysiology under elevated temperature improved with thermal pre-exposure (i.e., higher Fv/Fm), yet, this effect depended on host genotype and was influenced by active feeding as photochemical efficiency dropped in response to food deprivation. These findings highlight the role of temperature and partner fidelity in the establishment and performance of symbiosis and demonstrate the importance of heterotrophy for symbiotic cnidarians to endure and recover from stress.

Matched MeSH terms: Hot Temperature
Energy expenditure of soldiers in a warm humid climate

Haisman MF

Br J Nutr, 1972 Mar;27(2):375-81.
PMID: 5015257
Matched MeSH terms: Hot Temperature
Micellar electrokinetic chromatography method for the simultaneous determination of furanic compounds in honey and vegetable oils

Foo Wong Y, Makahleh A, Al Azzam KM, Yahaya N, Saad B, Sulaiman SA

Talanta, 2012 Aug 15;97:23-31.
PMID: 22841043 DOI: 10.1016/j.talanta.2012.03.056

A simple micellar electrokinetic chromatography (MEKC) method for the simultaneous determination of 2-furfural (2-F), 3-furfural (3-F), 5-methylfurfural (5-MF), 5-hydroxymethylfurfural (5-HMF), 2-furoic acid (2-FA) and 3-furoic acid (3-FA) in honey and vegetable oils is described. Parameters affecting the separation such as pH, buffer and surfactant concentrations, applied voltage, capillary temperature, injection time and capillary length were studied and optimized. The separation was carried out in normal polarity mode at 20 °C, 22 kV and using hydrodynamic injection (17 s). The separation was achieved in a bare fused-silica capillary (46 cm × 50 μm i.d.) with a background electrolyte of 75 mM phosphoric acid (pH 7.3), containing 200 mM of sodium dodecyl sulphate (SDS). The detection wavelengths were at 200 nm (2-FA and 3-FA) and 280 nm (2-F, 3-F, 5-MF, 5-HMF). The furfurals were well separated in less than 20 min. The method was validated in terms of linearity, limit of detection and quantitation, precision and recoveries. Calibration curves of the six furfurals were well correlated (r(2)>0.991) within the range 1-25 μg mL(-1). Relative standard deviations of intra- and inter-day migration times and corrected peak areas ≤9.96% were achieved. The limit of detection (signal:noise, 3) was 0.33-0.70 μg mL(-1) whereas the limit of quantitation (signal:noise, 10) was 1.00-2.12 μg mL(-1). The method was applied to the determination of furanic compounds in honeys and vegetable oils (palm, walnut, grape seed and rapeseed). The effects of thermal treatment and gamma irradiation on the formation of the furanic compounds in honey were also investigated.

Matched MeSH terms: Hot Temperature
A simple method for chromium speciation analysis in contaminated water using APDC and a pre-heated glass tube followed by HPLC-PDA

Salihu SO, Bakar NKA

Talanta, 2018 May 01;181:401-409.
PMID: 29426532 DOI: 10.1016/j.talanta.2018.01.041

In this study, a simple sample preparation method was developed for the determination of tri-and hexavalent chromium in water samples. It utilizes a pre-heated customized glass tube (CGT), to supply the heat energy required for the reaction of Cr(III) with ammonium pyrrolidinedithiocarbamate (APDC). The products of the Cr complexes, tris(1-pyrrolidinecarbodithioato)chromium(III) and bis(1-pyrrolidinecarbodithioato)[1-pyrrolidinecarbodithio(thioperoxoato)]chromium(III) were chromatographed with Shimadzu LC-20AT and Zobax Eclipse C18 (150mm × 4.6mm, 5µm) column using ACN: Water, (7:3, v/v) as the mobile phase. The concentration of Cr(III) ranged from 0.06mgL-1to 0.09mgL-1and that of Cr(VI) was between 0.02mgL-1to 0.04mgL-1in the samples. Percentage recoveries from spiked real samples were between 87% (tap water) to 110% (wastewater) for Cr(III) and 92% (pond water) to 117% (tap water) for Cr(VI). The limits of detection (LODs) were 0.0029mgL-1and 0.0014mg/L-1for Cr(III) Cr(VI) respectively. While the limits of quantitation (LOQs), were 0.0098mgL-1and 0.0047mgL-1for Cr(III) and Cr(VI) respectively. Method precision (RSD (%)) was 3.3% and 3.5% for Cr(III) and Cr(VI) respectively. The developed method was applied for the speciation analysis of chromium in drinking water, tap water, wastewater, river water, and pond water samples. Our findings proved the method is simple and inexpensive. The method was validated by the analysis of a certified reference material (CRM) SLRS-4. The percentage recovery and RSD(%) from the spiked CRM were 91% and 115% and 0.32% and 1.4% for Cr(III) and Cr(VI) respectively.

Matched MeSH terms: Hot Temperature
How Safe Is High-Speed Burring in Spine Surgery? An In Vitro Study on the Effect of Rotational Speed and Heat Generation in the Bovine Spine

Singh TS, Yusoff AH, Chian YK

Spine (Phila Pa 1976), 2015 Aug 1;40(15):E866-72.
PMID: 25996539 DOI: 10.1097/BRS.0000000000000985

In vitro animal cadaveric study.

Matched MeSH terms: Hot Temperature*
Roasting, smoking and dieting in response to birth: malay confinement in cross-cultural perspective

Manderson L

Soc Sci Med B, 1981 Oct;15(4):509-20.
PMID: 7323860 DOI: 10.1016/0160-7987(81)90025-9
Matched MeSH terms: Hot Temperature
Hot and cold in transformation: is Iban medicine humoral?

Barrett RJ, Lucas RH

Soc Sci Med, 1994 Jan;38(2):383-93.
PMID: 8140465

Iban categories of hot and cold are examined in the context of humoral medical systems in southeast Asia. These categories are more than binary and oppositional: they are also contradictory and can only be understood in terms of their capacity for transformation in 'depth'. Analysis of the Iban epistemology of temperature sensation reveals the limitations of reductionist empirical approaches to hot and cold. Illness is apprehended, at one level, in terms of unusual conjunctions of opposite temperatures which signify a deeper disturbance in the relationship between body and soul, humans and spirits. Iban therapy redefines and relocates these categories in their proper place and at their appropriate level. It progresses from hot lay treatments to cool ritual treatments, yet cannot be accounted for within a limited framework of homeostatic balance. This paper develops an ethnographically grounded definition of humoralism which emphasizes non-reductive logic, cultural practice and transformation. The key element, transformation, is defined as a transition between categories and a shift in the level of interpretation which fundamentally alter the Iban experience of body and illness.

Matched MeSH terms: Hot Temperature
Destructive heat and cooling prayer: Malay humoralism in pregnancy, childbirth and the postpartum period

Laderman C

Soc Sci Med, 1987;25(4):357-65.
PMID: 3686085 DOI: 10.1016/0277-9536(87)90274-7

Malaya, an ancient crossroads of trade, was the recipient of Chinese and Ayurvedic humoral ideas and, later, those of medieval Islam. These ideas were readily accepted by Malays, since they are highly congruent with pre-existing notions among aboriginal peoples of Malaya involving a hot-cold opposition in the material and spiritual universe and its effects upon human health. Islamic Malays have adapted these aboriginal beliefs to correspond to the Greek-Arabic humoral model in matters concerning foods, diseases, and medicines. Although Malay theories of disease causation include such concepts as soul loss and spirit attack, along with 'naturalistic' ideas such as dietary imbalance and systemic reactions to foods, all of these theories can either be reinterpreted in humoral terms, or, at least, are congruent with the basic tenets of Islamic humoral pathology. Behaviors and beliefs regarding human reproduction, however, while essentially following a humoral pattern, diverge from Islamic, as well as traditional Chinese and Indian Ayurvedic, humoral theories. Unlike any other major humoral doctrine, Malay reproductive theory (like that of non-Islamic aboriginal peoples of Malaya) equates coldness with health and fertility and heat with disease and sterility. These ideas, in turn, are related to beliefs regarding the nature of the spirit world: the destructiveness of spiritual heat and the efficacy of cooling prayer.

Matched MeSH terms: Hot Temperature*
Fulltext Effectiveness of a simple heated water-filled mattress for the prevention and treatment of neonatal hypothermia in the labour room

Boo NY, Selvarani S

Singapore Med J, 2005 Aug;46(8):387-91.
PMID: 16049607

This study aimed to determine the proportions of normothermic infants who remained normothermic, and hypothermic infants who became normothermic following the use of a heated water-filled mattress (HWM) in the labour room.

Matched MeSH terms: Hot Temperature
Fulltext Reheating of soy oil is detrimental to bone metabolism in oestrogen deficient rats

Ima-Nirwana S, Ahmad SN, Yee LJ, Loh HC, Yew SF, Norazlina M, et al.

Singapore Med J, 2007 Mar;48(3):200-6.
PMID: 17342287

The short-term and long- term effects of heated soy oil on bone metabolism in ovariectomised Sprague-Dawley rats were studied.

Matched MeSH terms: Hot Temperature/adverse effects*
Fulltext Hazards of complementary and alternative medicine

Chong VH, Yaakub AB

Singapore Med J, 2007 Jun;48(6):592; author reply 593.
PMID: 17538765
Matched MeSH terms: Hot Temperature
Fulltext A selective ultrahigh responding high temperature ethanol sensor using TiO2 nanoparticles

Arafat MM, Haseeb AS, Akbar SA

Sensors (Basel), 2014;14(8):13613-27.
PMID: 25072346 DOI: 10.3390/s140813613

In this research work, the sensitivity of TiO2 nanoparticles towards C2H5OH, H2 and CH4 gases was investigated. The morphology and phase content of the particles was preserved during sensing tests by prior heat treatment of the samples at temperatures as high as 750 °C and 1000 °C. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis were employed to characterize the size, morphology and phase content of the particles. For sensor fabrication, a film of TiO2 was printed on a Au interdigitated alumina substrate. The sensing temperature was varied from 450 °C to 650 °C with varying concentrations of target gases. Results show that the sensor has ultrahigh response towards ethanol (C2H5OH) compared to hydrogen (H2) and methane (CH4). The optimum sensing temperature was found to be 600 °C. The response and recovery times of the sensor are 3 min and 15 min, respectively, for 20 ppm C2H5OH at the optimum operating temperature of 600 °C. It is proposed that the catalytic action of TiO2 with C2H5OH is the reason for the ultrahigh response of the sensor.

Matched MeSH terms: Hot Temperature
Fulltext Luminescent measurement systems for the investigation of a scramjet inlet-isolator

Idris AC, Saad MR, Zare-Behtash H, Kontis K

Sensors (Basel), 2014;14(4):6606-32.
PMID: 24721773 DOI: 10.3390/s140406606

Scramjets have become a main focus of study for many researchers, due to their application as propulsive devices in hypersonic flight. This entails a detailed understanding of the fluid mechanics involved to be able to design and operate these engines with maximum efficiency even at their off-design conditions. It is the objective of the present cold-flow investigation to study and analyse experimentally the mechanics of the fluid structures encountered within a generic scramjet inlet at M = 5. Traditionally, researchers have to rely on stream-thrust analysis, which requires the complex setup of a mass flow meter, a force balance and a heat transducer in order to measure inlet-isolator performance. Alternatively, the pitot rake could be positioned at inlet-isolator exit plane, but this method is intrusive to the flow, and the number of pitot tubes is limited by the model size constraint. Thus, this urgent need for a better flow diagnostics method is addressed in this paper. Pressure-sensitive paint (PSP) has been applied to investigate the flow characteristics on the compression ramp, isolator surface and isolator sidewall. Numerous shock-shock interactions, corner and shoulder separation regions, as well as shock trains were captured by the luminescent system. The performance of the scramjet inlet-isolator has been shown to improve when operated in a modest angle of attack.

Matched MeSH terms: Hot Temperature
Fulltext Magnetically-Actuated Mixing and Merging of Acid-Base Micro-Droplets on Open Surfaces: Preliminary Study

Khaw MK, Mohd-Yasin F, Nguyen NT

Sensors (Basel), 2018 Jun 01;18(6).
PMID: 29857584 DOI: 10.3390/s18061767

We present the mixing and merging of two reactive droplets on top of an open surface. A mobile droplet (1.0 M HCl solution + iron oxide particles) is magnetically-actuated to merge with a sessile droplet (1.0 M NaOH + phenolphthalein). The heat from the exothermic reaction is detected by a thermocouple. We vary the droplet volume (1, 5 and 10 μL), the magnet speed (1.86, 2.79, 3.72 and 4.65 mm/s) and the iron oxide concentration (0.010, 0.020 and 0.040 g/mL) to study their influences on the mixing time, peak temperature and cooling time. The sampled recording of these processes are provided as supplementary files. We observe the following trends. First, the lower volume of droplet and higher speed of magnet lead to shorter mixing time. Second, the peak temperature increases and cooling time decreases at the increasing speed of magnet. Third, the peak temperature is similar for bigger droplets, and they take longer to cool down. Finally, we also discuss the limitations of this preliminary study and propose improvements. These observations could be used to improve the sensitivity of the open chamber system in measuring the exothermic reaction of biological samples.

Matched MeSH terms: Hot Temperature

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