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1.
Environ Int ; 158: 107002, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34991262

RESUMO

Urban green spaces (UGSs) reduce the surrounding temperature and create cooling areas as a buffer between people and high temperatures, thus helping residents adapt to the warming climate. However, the accessibility of UGS cooling services to the residents of cities remains largely unknown, which hinders decision-making regarding the formulation of climate adaptation and urban greening schemes. In the present study, we estimated the number of residents who accessed UGSs for cooling by analyzing the annual changes in such cooling areas during summer across 315 Chinese cities from 2003 to 2015. Approximately 93.3% of the cities showed significant decreasing trends (p < 0.05) of the total UGS area; as such the UGS coverage dropped from 12.23 ± 0.32% in 2003 to 7.69 ± 0.22% in 2015. Consequently, with the prevalent loss of UGS, the coverage of cooling spaces decreased from 32.55 ± 0.76% in 2003 to 24.39 ± 0.60% in 2015. This has formed a spatial mismatch between the growing urban population and the remaining UGSs. Accordingly, the number of residents of areas outside these cooling spaces increased by 4.23 million per year. In particular, the shortage of cooling services was more significant in cities with < 20,000 USD gross domestic product per capita and < 5 million residents than in the rest of the cities. To minimize the adverse impacts of increasing temperatures, focused greening plans are warranted, specifically in underdeveloped cities.


Assuntos
Temperatura Baixa , Parques Recreativos , Estações do Ano , China , Cidades , Temperatura Alta , Humanos
2.
Eur Phys J E Soft Matter ; 45(1): 2, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35006390

RESUMO

Latex paints are widely used, and many researchers pointed out that the film formation process depends on the deformability of dispersed polymer particles. However, the relationship between the film formation process and drying rate has not been totally understood due to the lack of accurate data on drying rate throughout the drying process. In the present study, we measured the drying rate of latex coating by the temperature change method proposed by Imakoma in convective drying. We revealed that the drying process significantly depends on particle deformability, especially in the former stage of the falling drying rate period. At a low drying temperature, the close-packed structure of polymer particles is formed throughout the film at the end of the constant drying rate period. On the other hand, partially deformed soft particles due to wet sintering inhibit the drying rate even under high moisture content at high drying temperatures. In either case, after forming the closest-packed structure, the shrinkage of the gap space between particles due to capillary deformation decreases the drying rate, proportional to the moisture content.


Assuntos
Convecção , Látex , Dessecação , Temperatura Alta , Polímeros
3.
J Phys Chem A ; 126(1): 3-15, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-34978833

RESUMO

Fluorinated carboxylic acids and their radicals are becoming more prevalent in environmental waters and soils as they have been produced and used for numerous commercial applications. Understanding the thermochemical properties of fluorinated carboxylic acids will provide insights into the stability and reaction paths of these molecules in the environment, in body fluids, and in biological and biochemical processes. Structures and thermodynamic properties for over 50 species related to fluorinated carboxylic acids with two and three carbons are determined with density functional computational calculations B3LYP, M06-2X, and MN15 and higher ab initio levels CBS-QB3, CBS-APNO, and G4 of theory. The lowest energy structures, moments of inertia, vibrational frequencies, and internal rotor potentials of each target species are determined. Standard enthalpies of formation, ΔfH298°, from CBS-APNO calculations show the smallest standard deviation among methods used in this work. ΔfH298° values are determined via several series of isodesmic and/or isogyric reactions. Enthalpies of formation are determined for fluorinated acetic and propionic acids and their respective radicals corresponding to the loss of hydrogen and fluorine atoms. Heat capacities as a function of temperature, Cp(T), and entropy at 298 K, S298°, are determined. Thermochemical properties for the fluorinated carbon groups used in group additivity are also developed. Bond dissociation energies (BDEs) for the carbon-hydrogen, carbon-fluorine, and oxygen-hydrogen (C-H, C-F, and O-H BDEs) in the acids are reported. The C-H, C-F, and O-H bond energies of the fluorinated carboxylic acids are in the range of 89-104, 101-125, and 109-113 kcal mol-1, respectively. General trends show that the O-H bond energies on the acid group increase with the increase in the fluorine substitution. The strong carbon fluorine bonds in a fluorinated acid support the higher stability of the perfluorinated acids in the environment.


Assuntos
Ácidos Carboxílicos , Temperatura Alta , Entropia , Termodinâmica
4.
Food Chem ; 374: 131808, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-35021581

RESUMO

This work evaluated the impact of high temperature short time (HTST, 72 °C, 15 s), high hydrostatic pressure (HHP, 400-600 MPa at 5 and 10 min) and Holder pasteurization (HoP, 62.5 °C, 30 min) on protein profile and aggregation in a human milk protein concentrate (HMPC). The structural changes induced in milk proteins were investigated in HMPC as well as in sedimentable and non-sedimentable fractions recovered after ultracentrifugation. The results showed that heat treatments induced more protein denaturation and aggregation than did HHP treatments. Indeed, heat-induced protein aggregates observed in HMPC and the sedimentable fraction were mainly composed of lactoferrin and α-lactalbumin. More specifically, the concentration of lactoferrin in HMPC decreased by 86% after HTST and HoP whereas no effect was observed after HHP treatment. These results show the potential of HHP processing as a pasteurization method for HMPC since it minimizes the impact on protein structure, which generally correlates to protein quality and bioactivity.


Assuntos
Proteínas do Leite , Pasteurização , Temperatura Alta , Humanos , Pressão Hidrostática , Proteínas do Leite/análise , Leite Humano/química , Temperatura
5.
Sensors (Basel) ; 22(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35009935

RESUMO

Recently, wet-bulb globe temperature (WBGT) has attracted a lot of attention as a useful index for measuring heat strokes even when core body temperature cannot be available for the prevention. However, because the WBGT is only valid in the vicinity of the WBGT meter, the actual ambient heat could be different even in the same room owing to ventilation, clothes, and body size, especially in hot specific occupational environments. To realize reliable heat stroke prevention in hot working places, we proposed a new personalized vital sign index, which is combined with several types of vital data, including the personalized heat strain temperature (pHST) index based on the temperature/humidity measurement to adjust the WBGT at the individual level. In this study, a wearable device was equipped with the proposed pHST meter, a heart rate monitor, and an accelerometer. Additionally, supervised machine learning based on the proposed personalized vital index was introduced to improve the prevention accuracy. Our developed system with the proposed vital sign index achieved a prevention accuracy of 85.2% in a hot occupational experiment in the summer season, where the true positive rate and true negative rate were 96.3% and 83.7%, respectively.


Assuntos
Transtornos de Estresse por Calor , Golpe de Calor , Temperatura Corporal , Temperatura Alta , Humanos , Aprendizado de Máquina Supervisionado
6.
Trop Anim Health Prod ; 54(1): 51, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35024924

RESUMO

This study aimed to evaluate the effects of different cooling strategies on milk yield and physiological and behavioral responses of Nili Ravi buffaloes during subtropical summer in Pakistan. Thirty Nili Ravi buffaloes were randomly assigned to three treatments: (1) CNT buffaloes cooled with the application of water using handheld hosepipe twice daily, 3 min each with a water flow rate of 40 L/min; (2) 2SS, buffaloes cooled with sprinklers twice daily; (3) 3SS, buffaloes cooled with sprinklers thrice daily. Each of the sprinkler sessions lasted for 1 h with a 12-min cycle (3 min water on, 9 min off). The trial was carried out from mid-July until the end of September 2019. The average ambient afternoon temperature humidity index was 86.9. The results indicated that the buffaloes in the 3SS group had lower respiration rate and rectal temperature than those in the CNT and the 2SS groups (P < 0.01). The 3SS group had more daily milk yield (P = 0.019) and milk fat % (P < 0.01) than the CNT and 2SS groups. The lying time and the lying bout length were significantly longer in the 3SS than in the CNT and 2SS groups. The blood cortisol levels tended to be lower in the 3SS group than in the CNT and 2SS groups (P = 0.051). In conclusion, the 3SS cooling strategy had more milk yield, more milk fat, and better welfare than the CNT strategy using less groundwater and both performed better than the 2SS strategy.


Assuntos
Búfalos , Lactação , Animais , Feminino , Temperatura Alta , Umidade , Leite
7.
Zhongguo Zhen Jiu ; 42(1): 85-90, 2022 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-35025163

RESUMO

Heat-sensitive moxibustion is the appropriate technique of the external treatment in traditional Chinese medicine and it is widely used in community because of its "easy learning, simple operation and clear curative effect". Pragmatic randomized controlled trial is a main intervention design in the real world study, which provides a high-level evidence for the effectiveness assessment of heat-sensitive moxibustion in community management. Focusing on the key links of randomization, e.g. block randomization, stratified randomization, cluster randomization, sample size allocation, allocation concealment and blinding, the paper elaborates the advantages, disadvantages and technical details of two-stage randomization with consideration of patient preference in pragmatic randomized controlled trials of heat-sensitive moxibustion in community. It facilitates improving the quality of evidence, reproducibility and methodological homogeneity among different trials.


Assuntos
Moxibustão , Temperatura Alta , Humanos , Preferência do Paciente , Distribuição Aleatória , Reprodutibilidade dos Testes
8.
Planta ; 255(2): 31, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982240

RESUMO

MAIN CONCLUSION: Cultivar-biased regulation of HSFB4a and HSFA7 mediates heat stress tolerance/sensitivity in tomato. Reduced HSFB4a repressor levels and enhanced HSFA7 activator levels govern thermo-tolerance in tolerant cultivars. Heat shock factors (HSFs) are at the core of heat stress (HS) response in plants. However, the contribution of HSFs governing the inherent thermo-tolerance mechanism in tomato from sub-tropical hot climates is poorly understood. With the above aim, comparative expression profiles of the HSF family in a HS-tolerant (CLN1621L) and -sensitive cultivars (CA4 and Pusa Ruby) of tomato under HS revealed cultivar-biased regulation of an activator (HSFA7) and a repressor (HSFB4a) class HSF. HSFA7 exhibited strong upregulation while HSFB4a showed downregulation in tolerant tomato cultivar upon HS. Functional characterization of HSFA7 and HSFB4a in a tolerant-sensitive cultivar pair by virus-induced gene silencing (VIGS)-based silencing and transient overexpression established them as a positive and a negative regulator of HS tolerance, respectively. Promoter:GUS reporter assays and promoter sequence analyses suggest heat-mediated transcriptional control of both the HSF genes in the contrasting cultivars. Moreover, degradome data highlighted HSFB4a is a probable target of microRNA Sly-miR4200. Transient in-planta Sly-MIR4200-effector:HSFB4a-reporter assays showed miRNA-dependent target down-regulation. Chelation of miRNA by short-tandem-target-mimic of Sly-miR4200 increased target abundance, highlighting a link between Sly-miR4200 and HSFB4a. This miRNA has induced several folds upon HS in the tolerant cultivar where HSFB4a levels are reduced, thus exhibiting the inverse miR:target expression. Thus, we speculate that the alleviation of HSFB4a and increased HSFA7 levels govern thermo-tolerance in the tolerant cultivar by regulating downstream heat stress-responsive genes.


Assuntos
Resposta ao Choque Térmico , Lycopersicon esculentum , Proteínas de Plantas , Termotolerância , Fatores de Transcrição , Regulação da Expressão Gênica de Plantas , Temperatura Alta , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
J Agric Food Chem ; 70(2): 626-633, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35000380

RESUMO

Peanut allergy is the leading pediatric food allergy. Many attempts have been made to reduce its allergenicity by processing. After roasting, Ara h 2 and its derivatives in the matrix were isolated by immunoaffinity chromatography (IAC). The structure and allergenicity of Ara h 2 were analyzed by circular dichroism, mass spectrometry (MS), western blotting, the enzyme-linked immunoassay, and cell modeling. Our results showed that a large portion of Ara h 2 was fragmented and cross-linked. Ara h 2 monomers accounted for only 13% of the total proteins after IAC purification. In addition, the structure of Ara h 2 changed after roasting. In addition to methylation and oxidation modification, the disulfide bonds of Ara h 2 were found to be rearranged after roasting. In the conformational structure of Ara h 2, the content of the α-helix decreased from 27.1 to 21.6% after roasting, while the content of the random coil increased from 29.1 to 34.3%. Six cleavage sites of trypsin were exposed, while three were covered. In terms of allergenicity, most of the cross-linking products were not recognized by patients' sera. Only one faint band around 40 kDa was observed in our blotting. For Ara h 2 monomers, roasting enhanced their IgE binding capacity and ability to stimulate the degranulation of basophils. The potential allergenicity increase of Ara h 2 monomers did not reflect the allergenicity change of Ara h 2 in the matrix due to the amount and property of its derivatives after roasting.


Assuntos
Arachis , Hipersensibilidade a Amendoim , Albuminas 2S de Plantas , Alérgenos , Antígenos de Plantas , Criança , Temperatura Alta , Humanos , Imunoglobulina E , Proteínas de Plantas
10.
PLoS One ; 17(1): e0257963, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34986162

RESUMO

In times of crisis, including the current COVID-19 pandemic, the supply chain of filtering facepiece respirators, such as N95 respirators, are disrupted. To combat shortages of N95 respirators, many institutions were forced to decontaminate and reuse respirators. While several reports have evaluated the impact on filtration as a measurement of preservation of respirator function after decontamination, the equally important fact of maintaining proper fit to the users' face has been understudied. In the current study, we demonstrate the complete inactivation of SARS-CoV-2 and preservation of fit test performance of N95 respirators following treatment with dry heat. We apply scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD) measurements, Raman spectroscopy, and contact angle measurements to analyze filter material changes as a consequence of different decontamination treatments. We further compared the integrity of the respirator after autoclaving versus dry heat treatment via quantitative fit testing and found that autoclaving, but not dry heat, causes the fit of the respirator onto the users face to fail, thereby rendering the decontaminated respirator unusable. Our findings highlight the importance to account for both efficacy of disinfection and mask fit when reprocessing respirators to for clinical redeployment.


Assuntos
COVID-19/prevenção & controle , Descontaminação/métodos , Reutilização de Equipamento , Respiradores N95/virologia , SARS-CoV-2/fisiologia , COVID-19/transmissão , Equipamentos e Provisões , Pessoal de Saúde , Temperatura Alta , Humanos , Pandemias
11.
Chemosphere ; 287(Pt 1): 131952, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34450371

RESUMO

In this study, the oxidative degradation of losartan (LOS), a widely administered medicine for high blood pressure by heat-activated persulfate was investigated. Increased temperature and persulfate concentration, as well as acidic conditions enhance the degradation efficiency of LOS, whose rate follows pseudo-first order kinetics. From the respective apparent rate constants in the range 40-60 °C, an apparent activation energy of 112.70 kJ/mol was computed. Radical scavenging tests demonstrated that both HO• and [Formula: see text] contribute towards LOS degradation. LOS degradation was suppressed in real water matrices including bottled water (BW) and secondary wastewater effluent (WW), while other experiments indicated that the presence of bicarbonates and humic acid negatively affected its oxidation. Instead, the addition of chloride ions at 250 mg/L resulted in a positive effect on LOS removal. The combination of heat-activated PS with low-frequency ultrasound exhibited a synergistic effect, with the ratio S being 2.29 in BW and 1.52 in WW. Five transformation products of LOS were identified through HRMS suspect and non-target screening approaches, among which two are reported for the first time. Using the in-house risk assessment program, ToxTrAMs was revealed that most of the identified TPs present higher toxicity than LOS against Daphnia magna.


Assuntos
Água Potável , Preparações Farmacêuticas , Poluentes Químicos da Água , Temperatura Alta , Cinética , Losartan , Oxirredução , Sulfatos , Poluentes Químicos da Água/análise
12.
J Environ Manage ; 301: 113792, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34607137

RESUMO

Jaggery is a kind of unrefined non-centrifugal sugar (NCS) used mainly in Asia, Africa, Latin America, and the Caribbean. Traditionally, jaggery is produced by concentrating sugarcane juice in open pans with the help of bagasse combustion. However, due to thermal energy loss with flue gases and an unscientific approach in plant construction, jaggery plants have a poor thermal efficiency of less than 25%, poor emission characteristics, and a high bagasse consumption rate. Advanced jaggery-making techniques use solar energy and heat pumps for jaggery production. However, these techniques are in the early stage of development, and the literature indicates that these techniques should be used in conjuction with traditional ones to improve the performance of jaggery making plants. This literature review describes advances in jaggery-making methods, critically analyzed them, and provides a qualitative comparison of these methods. Further, gaps in the existing literature are identified and reported for future research direction. In addition, efforts have been made to quantify and estimate the emissions reduction and bagasse consumption potentials from the traditional jaggery industry to make this rural industry a sustainable and profitable business for rural entrepreneurs. The comparison with the recently developed clean combustion device exhibits that the harmful emissions from the jaggery industry could be reduced drastically viz. 95%-98% of PM2.5; 92%-95% of CO, and 52-60% of CO2, while saving more than 35% of bagasse consumption. Implemented at a national scale, it may reduce nearly 3% of all harmful emissions in the country, which is equally applicable elsewhere.


Assuntos
Extratos Vegetais , Saccharum , Gases , Temperatura Alta
13.
J Environ Manage ; 301: 113863, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610558

RESUMO

This study presents the thermo-chemical conversion by means of pyrolysis as a route to valorise end of life tyres (ELTs) in a sustainable manner whilst targeting produced pyrolysis oil (pyro-oil) to replace conventional fossil fuels. The work presented here compares the results of pyro-oil extracted from the pyrolysis of three tyre grades, namely fresh (new) tyres, car and lorry truck ELTs; and investigates the pyro-oil extracted for fuel properties and common fuel hydrocarbon range. A fixed bed reactor system was used to conduct the experimental runs between 500 and 800 °C. The results show that fresh tyres and car ELTs yield some 45% of pyro-oil at an average reactor bed temperature equal to 600 °C which promotes evolution of liquid hydrocarbons via primary route of tyres cracking, hence pyro-oil production to a maximum. Furthermore, and at a similar operating temperature; the diesel range hydrocarbons (C10-C19) were around 66% of the total fuel like chromatograph studied for the pyrolysis oils. The work in this study and based on properties of fuel investigated point towards blending the oil extracted with conventional fuels that could result in lowering dependency on fossil based ones. Further upgrading is also possible whereby desulphurisation could lead to renewable and sustainable fuel source utilising a solid waste feedstock such as ELTs.


Assuntos
Óleos , Pirólise , Temperatura Alta , Hidrocarbonetos , Resíduos Sólidos , Temperatura
14.
Food Chem ; 370: 130507, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34619605

RESUMO

While the high internal phase emulsions (HIPEs) have been formed by food-grade biopolymers and granules have been widely reported, it is not known which components are more effective. In this work, we first used heat-treated lactoferrin (LF)-carboxymethyl chitosan (CMCTS) granules and native LF-CMCTS physical mixtures as emulsifiers to form HIPEs. The results showed that the interfacial behavior and emulsifying properties of the two complexes were controlled by the ratio of LF-CMCTS and the optimal ratio of LF to CMCTS was 1:1. Heated LF-CMCTS granules anchored to the water-oil interface and formed an elastic shell to stabilize HIPEs, while unheated LF-CMCTS complexes formed a thick film layer to stabilize HIPEs. Both HIPEs could act as delivery systems loaded with curcumin, and they showed better protection of curcumin than Tween-80 under light. This study provides a new basis for the design of LF-based HIPEs systems loaded with lipophilic food functional ingredients.


Assuntos
Quitosana , Lactoferrina , Emulsões , Temperatura Alta , Tamanho da Partícula
15.
J Environ Manage ; 301: 113832, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624578

RESUMO

Biomass-fuelled Combined Heat and Power Generation (CHP) systems can efficiently convert chemical energy contained in biomass into electricity and heat. Currently there is a large number of abandoned forests and biomass of agroforestry origin that is not being used. The use of residual biomass as a source of energy in CHP systems is presented as a particularly attractive alternative for energy obtention. This paper presents the results of a biomass boiler coupled to an Organic Rankine Cycle (ORC). Three residual biomasses, named pruning vine, pruning kiwi and gorse have been selected due to their potentiality and availability in the Galicia-North Portugal Euroregion. For this purpose, micro-cogeneration tests at bench scale were performed, based fundamentally on varying dissipation conditions in the low-grade temperature range (below 100 °C). Micro-cogeneration performance was assessed based on the electrical power and efficiency obtained, along with the global efficiency achieved (electrical plus thermal). Combustion measurements comprised gaseous emissions analyses and determination of the efficiency of the process. Micro-cogeneration results obtained show that differences in temperature between the hot and the cold source have a significant influence. The higher the temperature difference, the higher the electrical power and efficiency, as well as the higher global performance obtained, with values close to the maximum of the ORC employed (i.e 4 kWe, 9% and 96% respectively). Thus, the technical feasibility of the system to simultaneously obtain heat and electricity from low grade heat sources in small-scale applications was demonstrated. Regarding to combustion, parameters regulated by European emission standards are under the limits using the biofuels (residual biomasses) studied. Thereby, the suitability of those biomasses in thermochemical valorization processes was demostrated.


Assuntos
Biocombustíveis , Temperatura Alta , Biomassa , Eletricidade , Temperatura
16.
J Environ Manage ; 301: 113751, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34628283

RESUMO

Heat-related mortality is one of the leading causes of weather-related deaths in the United States. With changing climates and an aging population, effective adaptive strategies to address public health and environmental justice issues associated with extreme heat will be increasingly important. One effective adaptive strategy for reducing heat-related mortality is increasing tree cover. Designing such a strategy requires decision-support tools that provide spatial and temporal information about impacts. We apply such a tool to estimate spatially and temporally explicit reductions in temperature and mortality associated with a 10% increase in tree cover in 10 U.S. cities with varying climatic, demographic, and land cover conditions. Two heat metrics were applied to represent tree impacts on moderately and extremely hot days (relative to historical conditions). Increasing tree cover by 10% reduced estimated heat-related mortality in cities significantly, with total impacts generally greatest in the most populated cities. Mortality reductions vary widely across cities, ranging from approximately 50 fewer deaths in Salt Lake City to about 3800 fewer deaths in New York City. This variation is due to differences in demographics, land cover, and local climatic conditions. In terms of per capita estimated impacts, hotter and drier cities experience higher percentage reductions in mortality due to increased tree cover across the season. Phoenix potentially benefits the most from increased tree cover, with an estimated 22% reduction in mortality from baseline levels. In cooler cities such as Minneapolis, trees can reduce mortality significantly on days that are extremely hot relative to historical conditions and therefore help mitigate impacts during heat wave conditions. Recent studies project highest increases in heat-related mortality in the cooler cities, so our findings have important implications for adaptation planning. Our estimated spatial and temporal distributions of mortality reductions for each city provide crucial information needed for promoting environmental justice and equity. More broadly, the methods and model can be applied by both urban planners and the public health community for designing targeted, effective policies to reduce heat-related mortality. Additionally, land use managers can use this information to optimize tree plantings. Public stakeholders can also use these impact estimates for advocacy.


Assuntos
Temperatura Alta , Árvores , Cidades , Mortalidade , Saúde Pública , Estações do Ano , Estados Unidos
17.
Sci Total Environ ; 806(Pt 4): 150903, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653460

RESUMO

Co-pyrolysis of sophora wood (SW) and polyvinyl chloride (PVC) was conducted in a microwave reactor at different temperatures and different mixing ratios, and the transformation and distribution of chlorine in pyrolysis products were investigated. Microwave pyrolysis is a simple and efficient technique with better heating uniformity and process controllability than conventional heating. Compared with PVC pyrolysis, the addition of SW significantly reduced CO2 yield and greatly increased the yield of CO. The yield and quality of pyrolysis oil were effectively improved by SW, and the content of chlorine-containing compounds in the oil was suppressed to <1% at low temperatures (<550 °C). Co-pyrolysis of SW and PVC reduced the chlorine emissions from 59.07% to 28.09% and promoted the retention of chlorine in char (from 0.33% to 4.72%). Cellulose, hemicellulose, and lignin were co-pyrolyzed with PVC to investigate their effects on chlorine distribution. The experiments demonstrated that lignin had the most significant effects on reducing gas phase chlorine emission and achieving chlorine immobilization, and chlorine mainly existed in the form of sodium chloride in the char of lignin-PVC co-pyrolysis. Hence co-pyrolysis of lignocellulosic biomass and PVC provides a practical pathway for utilization of PVC waste in an environmentally friendly manner, realizing efficient chlorine retention and significantly reducing chlorine-related emissions.


Assuntos
Cloreto de Polivinila , Pirólise , Biomassa , Cloro , Temperatura Alta , Micro-Ondas
18.
Food Chem ; 375: 131878, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34952386

RESUMO

Soy protein is the main protein source for plant-based infant formula, whereas pea protein is considered as a potential alternative plant protein source. This study assessed the structural changes of soy and pea proteins after heating between 65 °C and 100 °C, and its effects on the in vitro digestibility in the context of infant digestion. We found that with increased heating intensity, both soy and pea proteins unfolded, manifested as the increased surface hydrophobicity, thereby potentially improving the accessibility to digestive enzymes. Their final in vitro digestibility increased from âˆ¼ 30% of non-treated samples to âˆ¼ 60% of 100 °C-heated samples for soy protein, and from âˆ¼ 52% to âˆ¼ 65% for pea protein. Surface hydrophobicity was strongly positively correlated to the overall digestibility. Therefore, the heating temperatures that enabled protein unfolding promoted the digestibility of soy and pea proteins under infant digestion conditions.


Assuntos
Proteínas de Ervilha , Proteínas de Plantas , Digestão , Temperatura Alta , Humanos , Lactente , Proteínas de Soja
19.
Zool Res ; 43(1): 52-63, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34821086

RESUMO

The ability to sense temperature changes is crucial for mammalian survival. Mammalian thermal sensing is primarily carried out by thermosensitive transient receptor potential channels (Thermo-TRPs). Some mammals hibernate to survive cold winter conditions, during which time their body temperature fluctuates dramatically. However, the underlying mechanisms by which these mammals regulate thermal responses remain unclear. Using quantitative real-time polymerase chain reaction (qRT-PCR) and the Western blotting, we found that Myotis ricketti bats had high levels of heat-activated TRPs (e.g., TRPV1 and TRPV4) during torpor in winter and cold-activated TRPs (e.g., TRPM8 and TRPC5) during active states in summer. We also found that laboratory mice had high mRNA levels of cold-activated TRPs (e.g., Trpm8 and Trpc5) under relatively hot conditions (i.e., 40 °C). These data suggest that small mammals up-regulate the expression of cold-activated TRPs even under warm or hot conditions. Binding site analysis showed that some homeobox (HOX) transcription factors (TFs) regulate the expression of hot- and cold-activated TRP genes and that some TFs of the Pit-Oct-Unc (POU) family regulate warm-sensitive and cold-activated TRP genes. The dual-luciferase reporter assay results demonstrated that TFs HOXA9, POU3F1, and POU5F1 regulate TRPC5 expression, suggesting that Thermo-TRP genes are regulated by multiple TFs of the HOX and POU families at different levels. This study provides insights into the adaptive mechanisms underlying thermal sensing used by bats to survive hibernation.


Assuntos
Quirópteros , Temperatura Alta , Estações do Ano , Canais de Cátion TRPC , Animais , Quirópteros/genética , Feminino , Hibernação/genética , Masculino , Camundongos , Canais de Cátion TRPC/genética , Canais de Cátion TRPV/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-34371155

RESUMO

Temperature is an important environmental factor influencing immune responses of crayfish. However, the mechanism underlying how temperature affects immune responses remains unclear. Here, we identified an ortholog of the transient receptor potential ankyrin subtype 1 (TRPA1), a temperature sensor of Drosophila, from Procambarus clarkii (PcTRPA1-1). Its expression was induced by high temperature and challenge with heat-killed A. hydrophila at high temperature, but not at lower temperature. PcTRPA1-1 silencing led to increased mortality of crayfish challenged with live A. hydrophila at high temperature (32 °C), but had no statistically significant effect on crayfish mortality at 24 °C. This suggests that PcTRPA1-1 is involved in the immune responses of crayfish at high temperature as a potential temperature sensor. Further assay exhibited that PcTRPA1-1 silencing affected immune responses of crayfish, including increase of lipid peroxidation, reduction of total antioxidant capacity, decreased phenoloxidase activity and disruption of circadian rhythm of total hemocyte count entrained by temperature cycles. PcTRPA1-1 silencing also decreased the expression of PcHSP70 and PcHSP90 which are responsive to heat stimuli and bacterial challenge. The results collectively indicate that TRPA1 contributes to heat sensing of crayfish and is required for crayfish defense against bacterial infection.


Assuntos
Aeromonas hydrophila , Astacoidea , Animais , Astacoidea/genética , Temperatura Alta , Imunidade Inata , Temperatura
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