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Fulltext FLIR vs SEEK thermal cameras in biomedicine: comparative diagnosis through infrared thermography

Kirimtat A, Krejcar O, Selamat A, Herrera-Viedma E

BMC Bioinformatics, 2020 Mar 11;21(Suppl 2):88.
PMID: 32164529 DOI: 10.1186/s12859-020-3355-7

BACKGROUND: In biomedicine, infrared thermography is the most promising technique among other conventional methods for revealing the differences in skin temperature, resulting from the irregular temperature dispersion, which is the significant signaling of diseases and disorders in human body. Given the process of detecting emitted thermal radiation of human body temperature by infrared imaging, we, in this study, present the current utility of thermal camera models namely FLIR and SEEK in biomedical applications as an extension of our previous article.
RESULTS: The most significant result is the differences between image qualities of the thermograms captured by thermal camera models. In other words, the image quality of the thermal images in FLIR One is higher than SEEK Compact PRO. However, the thermal images of FLIR One are noisier than SEEK Compact PRO since the thermal resolution of FLIR One is 160 × 120 while it is 320 × 240 in SEEK Compact PRO.
CONCLUSION: Detecting and revealing the inhomogeneous temperature distribution on the injured toe of the subject, we, in this paper, analyzed the imaging results of two different smartphone-based thermal camera models by making comparison among various thermograms. Utilizing the feasibility of the proposed method for faster and comparative diagnosis in biomedical problems is the main contribution of this study.

Matched MeSH terms: Body Temperature
Impact of heat stress on health-related symptoms and physiological changes among workers at a palm oil mill in Mukah, Sarawak, Malaysia

Vallennie V, Isa SNI, Mazlan AZ, Shaifuddin SNM

Med J Malaysia, 2024 Mar;79(Suppl 1):82-87.
PMID: 38555890

INTRODUCTION: The palm oil (PO) industry is one of the most important sectors in the Malaysian economy. Workers at PO mills are, however, at risk for a number of health and safety issues, including heat stress, as the PO is one of the industries with high heat exposure. Heat stress occurs when a person's body cannot get rid of excess heat. Heat stress can result in heat cramps, heat exhaustion, heat rash, and heat stroke. It also results in physiological and psychological changes that can have an impact on a worker's performance. Therefore, this study aimed to evaluate the impact of heat stress on health-related symptoms and physiological changes among workers in a PO mill.
MATERIALS AND METHODS: This cross-sectional study was conducted in a PO mill located in Mukah, Sarawak, Malaysia. Thirty-one workers from the four workstations (sterilizer, boiler, oil, and engine rooms) were selected as the respondents in this study. Wet Bulb Globe Thermometer was used in this study to measure the environmental temperature (WBGTin). Body core temperature (BCT), blood pressure (BP), and heart rate (HR) were recorded both before and after working in order to assess the physiological effects of heat stress on workers. A set of questionnaires were used to determine sociodemographic characteristics of the respondents and their symptoms related to heat stress. Data were then analyzed using SPSS Ver28.
RESULTS: The WBGTin was found to be above the ACGIH threshold limit value of heat stress exposure in the engine room, sterilizer, and boiler workstations (>28.0°C). Additionally, there was a significant difference in the worker's BCT in these three workstations before and after work (p<0.05). Only the systolic BP and HR of those working at the boiler workstation showed significant difference between before and after work (p<0.05). The most typical symptoms that workers experience as a result of being exposed to heat at work include headache and fatigue. However, statistical analysis using Spearman Rho's test showed that there is no correlation between heat stress level with physiological changes and health-related symptoms among study respondents (p>0.05).
CONCLUSION: Results of the present study confirmed that workers in PO mill were exposed to high temperatures while at work. Although the evidence indicates the physiological parameters in general are not significantly affected while working, it also demonstrated that worker's body adapts and acclimates to the level of heat. Even so, precautions should still be taken to reduce future heat exposure. It is recommended that a physiological study be carried out that focuses on cognitive function impairment to support the evidence regarding the effects of heat stress on PO mill workers.

Matched MeSH terms: Hot Temperature
Fulltext Optimisation of Epoxide Ring-Opening Reaction for the Synthesis of Bio-Polyol from Palm Oil Derivative Using Response Surface Methodology

Kamairudin N, Hoong SS, Abdullah LC, Ariffin H, Biak DRA

Molecules, 2021 Jan 27;26(3).
PMID: 33513686 DOI: 10.3390/molecules26030648

The development of bio-polyol from vegetable oil and its derivatives is gaining much interest from polyurethane industries and academia. In view of this, the availability of methyl oleate derived from palm oil, which is aimed at biodiesel production, provides an excellent feedstock to produce bio-polyol for polyurethane applications. In this recent study, response surface methodology (RSM) with a combination of central composite rotatable design (CCRD) was used to optimise the reaction parameters in order to obtain a maximised hydroxyl value (OHV). Three reaction parameters were selected, namely the mole ratio of epoxidised methyl oleate (EMO) to glycerol (1:5-1:10), the amount of catalyst loading (0.15-0.55%) and reaction temperature (90-150 °C) on a response variable as the hydroxyl value (OHV). The analysis of variance (ANOVA) indicated that the quadratic model was significant at 98% confidence level with (p-value > 0.0001) with an insignificant lack of fit and the regression coefficient (R2) was 0.9897. The optimum reaction conditions established by the predicted model were: 1:10 mole ratio of EMO to glycerol, 0.18% of catalyst and 120 °C reaction temperature, giving a hydroxyl value (OHV) of 306.190 mg KOH/g for the experimental value and 301.248 mg KOH/g for the predicted value. This result proves that the RSM model is capable of forecasting the relevant response. FTIR analysis was employed to monitor the changes of functional group for each synthesis and the confirmation of this finding was analysed by NMR analysis. The viscosity and average molecular weight (MW) were 513.48 mPa and 491 Da, respectively.

Matched MeSH terms: Temperature
Fulltext Electrical characterization of gold-DNA-gold structures in presence of an external magnetic field by means of I-V curve analysis

Khatir NM, Banihashemian SM, Periasamy V, Ritikos R, Majid WHA, Rahman SA

Sensors (Basel), 2012;12(3):3578-3586.
PMID: 22737025 DOI: 10.3390/s120303578

This work presents an experimental study of gold-DNA-gold structures in the presence and absence of external magnetic fields with strengths less than 1,200.00 mT. The DNA strands, extracted by standard method were used to fabricate a Metal-DNA-Metal (MDM) structure. Its electric behavior when subjected to a magnetic field was studied through its current-voltage (I-V) curve. Acquisition of the I-V curve demonstrated that DNA as a semiconductor exhibits diode behavior in the MDM structure. The current versus magnetic field strength followed a decreasing trend because of a diminished mobility in the presence of a low magnetic field. This made clear that an externally imposed magnetic field would boost resistance of the MDM structure up to 1,000.00 mT and for higher magnetic field strengths we can observe an increase in potential barrier in MDM junction. The magnetic sensitivity indicates the promise of using MDM structures as potential magnetic sensors.

Matched MeSH terms: Temperature
Comparative transcriptomics of the chilling stress response in two Asian mangrove species, Bruguiera gymnorhiza and Rhizophora apiculata

Short AW, Sebastian JSV, Huang J, Wang G, Dassanayake M, Finnegan PM, et al.

Tree Physiol, 2024 Feb 11;44(3).
PMID: 38366388 DOI: 10.1093/treephys/tpae019

Low temperatures largely determine the geographic limits of plant species by reducing survival and growth. Inter-specific differences in the geographic distribution of mangrove species have been associated with cold tolerance, with exclusively tropical species being highly cold-sensitive and subtropical species being relatively cold-tolerant. To identify species-specific adaptations to low temperatures, we compared the chilling stress response of two widespread Indo-West Pacific mangrove species from Rhizophoraceae with differing latitudinal range limits-Bruguiera gymnorhiza (L.) Lam. ex Savigny (subtropical range limit) and Rhizophora apiculata Blume (tropical range limit). For both species, we measured the maximum photochemical efficiency of photosystem II (Fv/Fm) as a proxy for the physiological condition of the plants and examined gene expression profiles during chilling at 15 and 5 °C. At 15 °C, B. gymnorhiza maintained a significantly higher Fv/Fm than R. apiculata. However, at 5 °C, both species displayed equivalent Fv/Fm values. Thus, species-specific differences in chilling tolerance were only found at 15 °C, and both species were sensitive to chilling at 5 °C. At 15 °C, B. gymnorhiza downregulated genes related to the light reactions of photosynthesis and upregulated a gene involved in cyclic electron flow regulation, whereas R. apiculata downregulated more RuBisCo-related genes. At 5 °C, both species repressed genes related to CO2 assimilation. The downregulation of genes related to light absorption and upregulation of genes related to cyclic electron flow regulation are photoprotective mechanisms that likely contributed to the greater photosystem II photochemical efficiency of B. gymnorhiza at 15 °C. The results of this study provide evidence that the distributional range limits and potentially the expansion rates of plant species are associated with differences in the regulation of photosynthesis and photoprotective mechanisms under low temperatures.

Matched MeSH terms: Cold Temperature
Fulltext Assessment of indoor thermal comfort temperature and related behavioural adaptations: a systematic review

Arsad FS, Hod R, Ahmad N, Baharom M, Ja'afar MH

Environ Sci Pollut Res Int, 2023 Jun;30(29):73137-73149.
PMID: 37211568 DOI: 10.1007/s11356-023-27089-9

Thermal comfort is linked to our health, well-being, and productivity. The thermal environment is one of the main factors that influence thermal comfort and, consequently, the productivity of occupants inside buildings. Meanwhile, behavioural adaptation is well known to be the most critical contributor to the adaptive thermal comfort model. This systematic review aims to provide evidence regarding indoor thermal comfort temperature and related behavioural adaptation. Studies published between 2010 and 2022 examining indoor thermal comfort temperature and behavioural adaptations were considered. In this review, the indoor thermal comfort temperature ranges from 15.0 to 33.8 °C. The thermal comfort temperature range varied depending on several factors, such as climatic features, ventilation mode, type of buildings, and age of the study population. Elderly and younger children have distinctive thermal acceptability. Clothing adjustment, fan usage, AC usage, and open window were the most common adaptive behaviour performed. Evidence shows that behavioural adaptations were also influenced by climatic features, ventilation mode, type of buildings, and age of the study population. Building designs should incorporate all factors that affect the thermal comfort of the occupants. Awareness of practical behavioural adaptations is crucial to ensure occupants' optimal thermal comfort.

Matched MeSH terms: Temperature
Paddy straw saccharification using immobilized laccase on magnetized multiwall carbon nanotubes

Yasmin HAN, Kunasundari B, Shuit SH, Tompang MF

Biotechnol Lett, 2024 Aug;46(4):559-569.
PMID: 38748066 DOI: 10.1007/s10529-024-03494-z

The effective recovery of the immobilized enzymes using magnetic carriers has led to growing interest in this technology. The objective of this research was to evaluate the efficiency of immobilized laccase on magnetized multiwall carbon nanotubes (m-MWCNTs) in terms of stability and reusability. Laccases were efficiently adsorbed onto magnetized multiwall carbon nanotubes (m-MWCNTs) synthesized using water. The concentration of 7 mg laccase/mL was found to be ideal for immobilization. The optimal activity of both free and immobilized laccases was observed at pH 5, while for the latter, the optimal temperature was shifted from 40 to 50 °C. Compared to the free laccase, the immobilized laccase exhibited a greater range of stability at more extreme temperatures. At the fourth cycle of reactions, the immobilized laccase exhibited more than 60% relative activity in terms of reusability. Based on the fourier-transform infrared spectroscopy (FTIR) peak at 2921 cm-1, saccharification of paddy straw using immobilized laccase verified lignin degradation. The easy recovery of the immobilized laccase on m-MWCNTs lends credence to its potential use in biomass hydrolysis.

Matched MeSH terms: Temperature
A study to examine the ageing behaviour of cold plasma-treated agricultural seeds

Ahmed N, Siow KS, Wee MFMR, Patra A

Sci Rep, 2023 Jan 30;13(1):1675.
PMID: 36717647 DOI: 10.1038/s41598-023-28811-w

Cold plasma (low pressure) technology has been effectively used to boost the germination and growth of various crops in recent decades. The durability of these plasma-treated seeds is essential because of the need to store and distribute the seeds at different locations. However, these ageing effects are often not ascertained and reported because germination and related tests are carried out within a short time after the plasma-treatment. This research aims to fill that knowledge gap by subjecting three different types of seeds (and precursors): Bambara groundnuts (water), chilli (oxygen), and papaya (oxygen) to cold plasma-treatment. Common mechanisms found for these diverse seed types and treatment conditions were the physical and chemical changes induced by the physical etching and the cold plasma on the seeds and subsequent oxidation, which promoted germination and growth. The high glass transition temperature of the lignin-cellulose prevented any physical restructuring of the surfaces while maintaining the chemical changes to continue to promote the seeds germination and growth. These changes were monitored over 60 days of ageing using water contact angle (WCA), water uptake, electrical conductivity, field emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS). The vacuum effect was also investigated to separate its effect from cold plasma (low pressure). This finding offers a framework for determining how long agricultural seeds that have received plasma treatment can be used. Additionally, there is a need to transfer this research from the lab to the field. Once the impact of plasma treatment on seeds has been estimated, it will be simple to do so.

Matched MeSH terms: Cold Temperature
Fulltext Recent Techniques in Determining the Effects of Climate Change on Depressive Patients: A Systematic Review

Ab Kader NI, Yusof UK, Khalid MNA, Nik Husain NR

J Environ Public Health, 2022;2022:1803401.
PMID: 35978588 DOI: 10.1155/2022/1803401

Climate change is amongst the most serious issues nowadays. Climate change has become a concern for the scientific community as it could affect human health. Researchers have found that climate change potentially impacts human mental health, especially among depressive patients. However, the relationship is still unclear and needs further investigation. The purpose of this systematic review is to systematically evaluate the evidence of the association between climate change effects on depressive patients, investigate the effects of environmental exposure related to climate change on mental health outcomes for depressive patients, analyze the current technique used to determine the relationship, and provide the guidance for future research. Articles were identified by searching specified keywords in six electronic databases (Google Scholar, PubMed, Scopus, Springer, ScienceDirect, and IEEE Digital Library) from 2012 until 2021. Initially, 1823 articles were assessed based on inclusion criteria. After being analyzed, only 15 studies fit the eligibility criteria. The result from included studies showed that there appears to be strong evidence of the association of environmental exposure related to climate change in depressive patients. Temperature and air pollution are consistently associated with increased hospital admission of depressive patients; age and gender became the most frequently considered vulnerability factors. However, the current evidence is limited, and the output finding between each study is still varied and does not achieve a reasonable and mature conclusion regarding the relationship between the variables. Therefore, more evidence is needed in this domain study. Some variables might have complex patterns, and hard to identify the relationship. Thus, technique used to analyze the relationship should be strengthened to identify the relevant relationship.

Matched MeSH terms: Temperature
Remote sensing-based seasonal surface urban heat island analysis in the mining and industrial environment

Halder B, Bandyopadhyay J, Ghosh N

Environ Sci Pollut Res Int, 2024 May;31(25):37075-37108.
PMID: 38760605 DOI: 10.1007/s11356-024-33603-4

Cooling spaces have an optimistic influence on surface urban heat islands (SUHI). Blue spaces benefit from balancing the changing climate and heat variations. Because of the rapid deforestation and SUHI increase, the climate is gradually changing in Paschim Bardhhaman, West Bengal state, India. Paschim Bardhhaman has two sectors: specifically, Durgapur is the main industrial centre and Asansol has coal mines. This investigation aims to categorize spatiotemporal variations and seasonal differences in cooling spaces and their influence on SUHI, land use and land cover (LULC), and thermal differences using Landsat datasets for the years 1992, 2004, 2012, and 2022 in summer and winter. The coal mining and industrial range decreased from 10,391.92 (1992) to 3591.1 ha (2022), respectively. Open pit mining distresses fresh water by heavy water uses in ore processing, and mining water was applied to excerpt minerals. Among the two sub-divisions, the blue space amount was higher in Asansol because mining actions were higher in Asansol than in Durgapur. The open vegetation volume has reduced from 46,441.03 (1992) to 25,827.55 ha (2022) and dense vegetation has erased from 7368.02 (1992) to 15,608.56 ha (2022). Dense vegetation improved because of heavy precipitation in those regions. Mostly, Raghunathpur, Saraswatiganja, Bhagabanpur, Bistupur, Paschim Gangaram, Garkilla Kherobari, and Gourbazar have dense vegetation. The outcomes similarly demonstrate that the total built-up part has increased by 8412.82 ha in between 30 years. The built-up zone changes near the southeast and western Paschim Bardhhaman district. Those region needs appropriate attention and planning to survive soon.

Matched MeSH terms: Hot Temperature
Evaluation of DursbanR and Dowco 214 as mosquito larvicides in rice-fields

Yap HH, Ho SC

Southeast Asian J Trop Med Public Health, 1977 Mar;8(1):63-70.
PMID: 70078

Emulsifiable concentrates of DursbanR (chlorpyrifos) and Dowco 214 (chlorpyrifos-methyl) were tested as mosquito larvicides using Hudson knapsack sprayers on small plots of rice-fields on Penang Island. The mosquitoes found in these rice-fields are predominantly Anopheles campestris and Culex tritaeniorhynchus. At dosages of 14, 28 and 56 gm hectare-1, Dursban is effective in maintaining the rice-fields free of Anopheles larvae for at least 2, 3 and 7 days respectively. Dowco 214 at 56 gm hectare-1 is able to keep the fields free of all mosquito larvae for at least 2 days.

Matched MeSH terms: Temperature
Fulltext The influence of the ambient temperature on blood pressure and how it will affect the epidemiology of hypertension in Asia

Park S, Kario K, Chia YC, Turana Y, Chen CH, Buranakitjaroen P, et al.

J Clin Hypertens (Greenwich), 2020 Mar;22(3):438-444.
PMID: 31851429 DOI: 10.1111/jch.13762

Epidemiologic studies have consistently demonstrated an increased risk of cardiovascular disease during colder temperatures. Hemodynamic changes associated with cold temperature and an increase in thrombogenicity may both account for the increase in cardiovascular risk and mortality. Studies using both in-office and out-of-office BP measurements have consistently shown an elevation in BP during the colder seasons. The large difference in BP between cold and warm months may increase the incidence of hypertension and reduce the hypertension control rate, potentially resulting in increased cardiovascular risk, especially among those at risk of cardiovascular disease. The current trends in global warming and climate change may have a profound impact on the epidemiology of hypertension and cardiovascular disease, as changes in the climate may significantly affect both BP variability and cardiovascular disease, especially in those with high cardiovascular risk and the elderly. Furthermore, climate change could have a significant influence on hypertension in Asia, considering the unique characteristics of hypertensive patients in Asia. As an increase in ambient temperature decreases the mean daytime average and morning surge in BP, but increases the nocturnal BP, it is difficult to predict how environmental changes will affect the epidemiology and prognosis of hypertension in the Asian-Pacific region. However, these seasonal variations in BP could be minimized by adjusting the housing conditions and using anticipation medicine. In this review, we discuss the impact of seasonal variation in the ambient temperature on hypertension and cardiovascular disease and discuss how this may impact the epidemiology of hypertension and cardiovascular disease.

Matched MeSH terms: Temperature
Novel PEX1 mutations in fibroblasts from children with Zellweger spectrum disorders exhibit temperature sensitive characteristics

Liang JS, Hung KL, Lin LJ, Ong WP, Keng WT, Lu JF

Epilepsy Behav, 2023 Aug;145:109266.
PMID: 37385119 DOI: 10.1016/j.yebeh.2023.109266

Zellweger spectrum disorders (ZSD) are rare autosomal recessive disorders caused by defects in peroxisome biogenesis factor (PEX; peroxin) genes leading to impaired transport of peroxisomal proteins with peroxisomal targeting signals (PTS). Four patients, including a pair of homozygotic twins, diagnosed as ZSD by genetic study with different clinical presentations and outcomes as well as various novel mutations are described here. A total of 3 novel mutations, including a nonsense, a frameshift, and a splicing mutation, in PEX1 from ZSD patients were identified and unequivocally confirmed that the p.Ile989Thr mutant PEX1 exhibited temperature-sensitive characteristics and is associated with milder ZSD. The nature of the p.Ile989Thr mutant exhibited different characteristics from that of the other previously identified temperature-sensitive p.Gly843Asp PEX1 mutant. Transcriptome profiles under nonpermissive vs. permissive conditions were explored to facilitate the understanding of p.Ile989Thr mutant PEX1. Further investigation of molecular mechanisms may help to clarify potential genetic causes that could modify the clinical presentation of ZSD.

Matched MeSH terms: Temperature
Fulltext Simple and efficient estimation of photovoltaic cells and modules parameters using approximation and correction technique

Muhammad FF, Karim Sangawi AW, Hashim S, Ghoshal SK, Abdullah IK, Hameed SS

PLoS One, 2019;14(5):e0216201.
PMID: 31048867 DOI: 10.1371/journal.pone.0216201

The behavior of solar cells and modules under various operational conditions can be determined effectively when their intrinsic parameters are accurately estimated and used to simulate the current-voltage (I-V) characteristics. This work proposed a new computational approach based on approximation and correction technique (ACT) for simple and efficient extraction of solar cells and modules parameters from the single-diode model. In this technique, an approximated value of series resistance (Rs) was first derived and used to determine the initial value of parallel resistance (Rp). Later, the final corrected values of Rs and Rp were obtained by resubstituting their approximated values in a five-loop iteration using the manipulated equations. For rapid evaluation and validation of the proposed technique, a software application was also created using MATLAB program. The correctness and robustness of the proposed technique was validated on five types of solar cells and modules operated at varied temperatures and irradiances. The lowest RMSE value was achieved for RTC France (7.78937E-4) and PVM 752 GaAs (2.10497E-4) solar cell. The legitimacy of ACT extracted parameters was established using a simple yet competitive implementation approach wherein the performance of the developed technique was compared with several state-of-the-art methods recently reported in the literature.

Matched MeSH terms: Temperature
Fulltext Temperature vegetation dryness index (TVDI) for drought monitoring in the Guangdong Province from 2000 to 2019

Chen A, Jiang J, Luo Y, Zhang G, Hu B, Wang X, et al.

PeerJ, 2023;11:e16337.
PMID: 38130929 DOI: 10.7717/peerj.16337

Drought monitoring is crucial for assessing and mitigating the impacts of water scarcity on various sectors and ecosystems. Although traditional drought monitoring relies on soil moisture data, remote sensing technology has have significantly augmented the capabilities for drought monitoring. This study aims to evaluate the accuracy and applicability of two temperature vegetation drought indices (TVDI), TVDINDVI and TVDIEVI, constructed using the Normalized Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI) vegetation indices for drought monitoring. Using Guangdong Province as a case, enhanced versions of these indices, developed through Savitzky-Golay filtering and terrain correction were employed. Additionally, Pearson correlation analysis and F-tests were utilized to determine the suitability of the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI) in correlation with TVDINDVI and TVDIEVI. The results show that TVDINDVI had more meteorological stations passing both significance test levels (P

Matched MeSH terms: Temperature
Response of Coptotermes curvignathus (Isoptera: Rhinotermitidae) to formaldehyde catcher-treated particleboard

Lee SH, H'ng PS, Peng TL, Lum WC

Pak J Biol Sci, 2013 Nov 01;16(21):1415-8.
PMID: 24511759

The objective of this study is to investigate the feasibility of formaldehyde catcher as termites repellent. Single-layered UF-bonded particleboard was post-treated with formaldehyde catcher and heat respectively. Besides that, some boards were also produced with the formaldehyde catcher was added into the resin during the blending process, called add-in method. Particleboard post-treated with formaldehyde catcher reported the most severe attack. Heat-treated particleboard showed slightly better durability than the control blocks while the add-in catcher showed the best durability among three methods. A valid test was obtained as the termites survived the first week of the test. However, all the termites were found dead at the end of the test.

Matched MeSH terms: Hot Temperature
Analysis of Condition Index in Polymesoda expansa (Mousson 1849)

Abdul Rahim A, Idris MH, Kamal AH, Wong SK, Arshad A

Pak J Biol Sci, 2012 Jul 01;15(13):629-34.
PMID: 24218932

The Condition Index (CI) is a method to measure overall health of fish and that has been applied to estimate the effect that different environmental factors have on clam meat quality. The CI of local mangrove clam Polymesoda expansa in Kelulit, Miri Sarawak was determined from October 2010 to November 2011. Condition index that is generally used to characterize the physiological activity of organisms, varied from 1.8% in December 2010 to 3.4% in October 2011, with low values observed during the spawning period. The clam attained their best condition in quality of flesh weight during July-October. In present study, the CI showed a clear relationship with the reproductive cycle of P. expansa. However, no significant correlation (p > 0.05) was found between CI and the different physicochemical parameter of seawater. The data presented is necessary for developing sustainable management strategies and broodstock selection for the species which is crucial in aquaculture development.

Matched MeSH terms: Temperature
Growth kinetics of Bacillus cytotoxicus in liquid Egg yolk during treatment with phospholipase A2 - A one-step global dynamic analysis

Huang L, Ahmad NH, Juneja V, Stapp-Kamotani E, Gabiola J, Minocha U, et al.

Food Microbiol, 2024 Apr;118:104420.
PMID: 38049265 DOI: 10.1016/j.fm.2023.104420

During commercial production of liquid egg yolk (LEY), phospholipase A2 (PLA2) is used to improve its emulsification capacity and thermal stability. The enzymatic treatment may occur at elevated temperatures such as 50 °C, potentially allowing foodborne pathogens, such as Bacillus cereus, to grow. Little knowledge is available concerning growth of B. cereus in LEY during PLA2 treatment. Therefore, the objective of this study was to investigate the growth kinetics of B. cereus during PLA2 treatment using pathogenic B. cytotoxicus NVH391-98, the most thermotolerant member in the B. cereus group, as a surrogate. Inoculated LEY samples were placed in precision programmable incubators to observe the growth of B. cytotoxicus NVH391-98 under multiple isothermal and dynamic temperature conditions between 20 and 53 °C. The bacterial growth was described using the differential Baranyi model coupled with two different secondary models. The kinetic parameters were determined using one-step dynamic inverse analysis of multiple growth curves. The least square method was used in combination with the 4th order Runge-Kutta method to solve the differential Baranyi model using multiple growth curves to determine the cardinal kinetic parameters. The results showed that B. cytotoxicus NVH391-98 can grow prolifically at 50 °C. The estimated minimum, optimum and maximum temperatures were 16.7 or 18.5, 47.8 or 48.1, and 52.1 or 52.4 °C, respectively, depending on the secondary models, with an optimum growth rate of 2.1 log colony-forming-unit (CFU)/g per hour. The dynamic model is validated using isothermal curves with reasonable accuracy. B. cytotoxicus died off slowly at 15 °C. At 55 °C, thermal inactivation was observed, with a D value of approximately 2.7 h. Holding at 55 °C or below 15 °C can effectively prevent the growth of B. cytotoxicus in egg yolk.

Matched MeSH terms: Temperature
Geographical Diversity of Proteomic Responses to Cold Stress in the Fungal Genus Pseudogymnoascus

Abu Bakar N, Lau BYC, González-Aravena M, Smykla J, Krzewicka B, Karsani SA, et al.

Microb Ecol, 2023 Dec 07;87(1):11.
PMID: 38060022 DOI: 10.1007/s00248-023-02311-w

In understanding stress response mechanisms in fungi, cold stress has received less attention than heat stress. However, cold stress has shown its importance in various research fields. The following study examined the cold stress response of six Pseudogymnoascus spp. isolated from various biogeographical regions through a proteomic approach. In total, 2541 proteins were identified with high confidence. Gene Ontology enrichment analysis showed diversity in the cold stress response pathways for all six Pseudogymnoascus spp. isolates, with metabolic and translation-related processes being prominent in most isolates. 25.6% of the proteins with an increase in relative abundance were increased by more than 3.0-fold. There was no link between the geographical origin of the isolates and the cold stress response of Pseudogymnoascus spp. However, one Antarctic isolate, sp3, showed a distinctive cold stress response profile involving increased flavin/riboflavin biosynthesis and methane metabolism. This Antarctic isolate (sp3) was also the only one that showed decreased phospholipid metabolism in cold stress conditions. This work will improve our understanding of the mechanisms of cold stress response and adaptation in psychrotolerant soil microfungi, with specific attention to the fungal genus Pseudogymnoascus.

Matched MeSH terms: Cold Temperature
Waste-to-energy: Co-pyrolysis of potato peel and macroalgae for biofuels and biochemicals

Fardi Z, Shahbeik H, Nosrati M, Motamedian E, Tabatabaei M, Aghbashlo M

Environ Res, 2024 Feb 01;242:117614.
PMID: 37996005 DOI: 10.1016/j.envres.2023.117614

Waste-to-energy conversion presents a pivotal strategy for mitigating the energy crisis and curbing environmental pollution. Pyrolysis is a widely embraced thermochemical approach for transforming waste into valuable energy resources. This study delves into the co-pyrolysis of terrestrial biomass (potato peel) and marine biomass (Sargassum angastifolium) to optimize the quantity and quality of the resultant bio-oil and biochar. Initially, thermogravimetric analysis was conducted at varying heating rates (5, 20, and 50 °C/min) to elucidate the thermal degradation behavior of individual samples. Subsequently, comprehensive analyses employing FTIR, XRD, XRF, BET, FE-SEM, and GC-MS were employed to assess the composition and morphology of pyrolysis products. Results demonstrated an augmented bio-oil yield in mixed samples, with the highest yield of 27.1 wt% attained in a composition comprising 75% potato peel and 25% Sargassum angastifolium. As confirmed by GC-MS analysis, mixed samples exhibited reduced acidity, particularly evident in the bio-oil produced from a 75% Sargassum angastifolium blend, which exhibited approximately half the original acidity. FTIR analysis revealed key functional groups on the biochar surface, including O-H, CO, and C-O moieties. XRD and XRF analyses indicated the presence of alkali and alkaline earth metals in the biochar, while BET analysis showed a surface area ranging from 0.64 to 1.60 m2/g. The favorable characteristics of the products highlight the efficacy and cost-effectiveness of co-pyrolyzing terrestrial and marine biomass for the generation of biofuels and value-added commodities.

Matched MeSH terms: Hot Temperature

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