Study of the composition of coaxial microfibers with phase change materials under thermal analysis

Asphalt pavements cover a large area of urban centers and are directly related to Urban Heat Islands (UHI). These materials heat up by absorbing a large amount of solar energy and then slowly release it, generating environmental, economic and social impacts that directly harm the well-being of citizens. The use of Phase Change Materials (PCM) in asphalt mixtures is indicated in the literature as an efficient thermoregulation method to mitigate UHI. However, their direct incorporation in asphalt mixtures presents some disadvantages related to modifying the asphalt structure after PCM melting. The development of Coaxial Polymeric Fibers (CPF) emerges as an innovative alternative to incorporate PCM in asphalt mixtures. Thus, the research herein reported aims to produce and select the best composition of coaxial fibers composed of Polyethylene glycol (PEG) as PCM and core and cellulose acetate (Mn: 30,000 and 50,000) as sheath. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used for thermal characterization. TGA was used to analyse whether the materials could tolerate the mixing and compaction temperatures of the asphalt mixtures (up to about 200°C) without any mass loss, and DSC to assess the melting point for the CPF. Thereby it is possible to determine the effect of cellulose acetate molecular weight on the phase change temperature of PEG inside the CPF. This information will aid in deciding on suitable materials for asphalt concrete mixtures capable of withstanding asphalt mixing temperatures

Coaxial fibres incorporated with phase change materials for thermoregulation applications

Nowadays, the growing concern about improving thermal comfort in different structures (textiles, buildings, and pavements, among others) has stimulated research into phase change materials (PCMs). The direct incorporation of PCMs into composite materials can cause mechanical impacts. Therefore, this study focuses on the design of phase change coaxial fibres (PCFs), using commercial cellulose acetate (CA) or recycled CA obtained from cotton fabrics (CAt) as the sheath and polyethylene glycol (PEG) 2000 as the core, via the wet spinning method; the fibres vary in molecular weight, concentration and ejection velocity. The fibres were assessed for their optical, chemical, thermal, and mechanical properties. The presence of PEG2000 is confirmed in the core of the fibres. Thermal analyses revealed a mass loss at high temperatures, attributable to the presence of PEG2000. Notably, the fibres with CA (Mn 30,000) showed superior thermal and mechanical performance. The melting point of PEG2000 incorporated into these PCFs coincided with the melting point of pure PEG2000 (about 55 °C), with a slight deviation, indicating that PCFs were obtained. Finally, the results point to the application of the fibres in civil engineering materials requiring a phase change between 50 and 60 °C, providing promising prospects for their use in applications requiring thermoregulatory properties.This research was funded by the Portuguese Foundation for Science and Technology (FCT) under the projects MicroCoolPav EXPL/EQUEQU/1110/2021 and NanoAir PTDC/FISMAC/6606/2020 (https://doi.org/10.54499/PTDC/FIS-MAC/6606/2020) and within the framework of Strategic Funding UIDB/04650/2020, UIDB/04029/2020 (https://doi.org/10.54499/UIDB/04029/2020) and UID/QUI/0686/2020. I.R.S. and H.P.F. would like to thank FCT for their funding contracts 2022.00763.CEECIND (https://doi.org/10.54499/2022.00763.CEECIND/CP1718/CT0006) and 2021.02720.CEECIND (https://doi.org/10.54499/DL57/2016/CP1377/CT0098)

Reducing the effects of Low Albedo of asphalt materials incorporating Polyethylene Glycol (PEG) 1000, 2000 and 4000 as Phase Change Materials (PCM)

Albedo plays a vital role in urban microclimates. Civil engineering structures usually absorb a high amount of energy in form of heat, for example asphalt pavements, which have a low albedo, thus contributing to the Urban Heat Island (UHI) effects. Modifying the physical characteristics of asphalt pavements, including reflectance and thermal properties, can help mitigate UHI. The literature points out that one alternative to thermoregulating asphalt materials is the incorporation of phase change materials. Thus, the main goal of this research is to present a systematic review regarding the effectiveness of the incorporation of polyethylene glycol (PEG) 1000, 2000 and 4000 as Phase Change Material (PCM) in asphalt materials. The results showed that incorporating PEG into asphalt materials can regulate heat storage, promoting stability and reducing UHI effects. PEG2000 was more frequently used. PEGs can reduce between of 3.5 and 4.2ºC of the asphalt materials when compared to the conventional ones.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UIDB/04650/2020 and the projectsMicroCoolPav project EXPL/EQU-EQU/1110/2021, and NanoAir project PTDC/FISMAC/6606/2020

Evidences of herbal medicine-derived natural products effects in inflammatory lung diseases

Pulmonary inflammation is a hallmark of many respiratory diseases such as asthma, chronic obstructive pulmonary disease (COPD), and acute respiratory syndrome distress (ARDS). Most of these diseases are treated with anti-inflammatory therapy in order to prevent or to reduce the pulmonary inflammation. Herbal medicine-derived natural products have been used in folk medicine and scientific studies to evaluate the value of these compounds have grown in recent years. Many substances derived from plants have the biological effects in vitro and in vivo, such as flavonoids, alkaloids, and terpenoids. Among the biological activities of natural products derived from plants can be pointed out the anti-inflammatory, antiviral, antiplatelet, antitumor anti-allergic activities, and antioxidant. Although many reports have evaluated the effects of these compounds in experimental models, studies evaluating clinical trials are scarce in the literature. This review aims to emphasize the effects of these different natural products in pulmonary diseases in experimental models and in humans and pointing out some possible mechanisms of action.CNPq [300546/2012-2, 304465/2012-7, 476877/2012-1]FAPESP [2010/14831-3, 2011/15817-7, 2008/55359-5]Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Federal University of São Paulo, Diadema-SP 09972-270, BrazilSchool of Medicine, University of São Paulo, São Paulo-SP 01246903, BrazilInstituto de Saúde e Sociedade, Federal University of São Paulo, Santos-SP 11015-020, BrazilInstituto de Ciências Ambientais, Químicas e Farmacêuticas, Federal University of São Paulo, Diadema-SP 09972-270, BrazilInstituto de Saúde e Sociedade, Federal University of São Paulo, Santos-SP 11015-020, BrazilCNPq: 300546/2012-2CNPq: 304465/2012-7CNPq: 476877/2012-1FAPESP: 2010/14831-3FAPESP: 2011/15817-7FAPESP: 2008/55359-5Web of Scienc

Advancements in phase change materials in asphalt pavements for mitigation of urban heat island effect: bibliometric analysis and systematic review

This research presents a dual-pronged bibliometric and systematic review of the integration of phase change materials (PCMs) in asphalt pavements to counteract the urban heat island (UHI) effect. The bibliometric approach discerns the evolution of PCM-inclusion asphalt research, highlighting a marked rise in the number of publications between 2019 and 2022. Notably, Chang’an University in China has emerged as a leading contributor. The systematic review addresses key questions like optimal PCM types for UHI effect mitigation, strategies for PCM leakage prevention in asphalt, and effects on mechanical properties. The findings identify polyethylene glycols (PEGs), especially PEG2000 and PEG4000, as prevailing PCMs due to their wide phase-change temperature range and significant enthalpy during phase transitions. While including PCMs can modify asphalt’s mechanical attributes, such mixtures typically stay within performance norms. This review emphasises the potential of PCMs in urban heat management and the need for further research to achieve optimal thermal and mechanical balanceThis research was partially funded by the Portuguese Foundation for Science and Technology (FCT) under the framework of the projects MicroCoolPav EXPL/EQU-EQU/1110/2021, NanoAir PTDC/FIS-MAC/6606/2020, UIDB/04650/2020, and UIDB/04029/2020. This research was also supported by the doctoral Grant PRT/BD/154269/2022 financed by the FCT, and with funds from POR Norte-Portugal 2020 and State Budget, under MIT Portugal Program. I.R.S. would like to acknowledge the FCT for funding (2022.00763.CEECIND). V.C.B. acknowledges the Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico (Funcap), MLC-0191- 00144.01.00/22 (Edital Mulheres na Ciência), and the National Council for Scientific and Technological Development (CNPq), Process 404978/2021-5—Call CNPq/MCTI/FNDCT N° 18/2021—Faixa B—Consolidated Groups

Pulmonary Inflammation Is Regulated by the Levels of the Vesicular Acetylcholine Transporter

Acetylcholine (ACh) plays a crucial role in physiological responses of both the central and the peripheral nervous system. Moreover, ACh was described as an anti-inflammatory mediator involved in the suppression of exacerbated innate response and cytokine release in various organs. However, the specific contributions of endogenous release ACh for inflammatory responses in the lung are not well understood. To address this question we have used mice with reduced levels of the vesicular acetylcholine transporter (VAChT), a protein required for ACh storage in secretory vesicles. VAChT deficiency induced airway inflammation with enhanced TNF-alpha and IL-4 content, but not IL-6, IL-13 and IL-10 quantified by ELISA. Mice with decreased levels of VAChT presented increased collagen and elastic fibers deposition in airway walls which was consistent with an increase in inflammatory cells positive to MMP-9 and TIMP-1 in the lung. In vivo lung function evaluation showed airway hyperresponsiveness to methacholine in mutant mice. The expression of nuclear factor-kappa B (p65-NF-kappa B) in lung of VAChT-deficient mice were higher than in wild-type mice, whereas a decreased expression of janus-kinase 2 (JAK2) was observed in the lung of mutant animals. Our findings show the first evidence that cholinergic deficiency impaired lung function and produce local inflammation. Our data supports the notion that cholinergic system modulates airway inflammation by modulation of JAK2 and NF-kappa B pathway. We proposed that intact cholinergic pathway is necessary to maintain the lung homeostasis

Structurally Related Monoterpenes p-Cymene, Carvacrol and Thymol Isolated from Essential Oil from Leaves of Lippia sidoides Cham. (Verbenaceae) Protect Mice against Elastase-Induced Emphysema

Background: Chronic obstructive pulmonary disease (COPD) is characterized by irreversible airflow obstruction and inflammation. Natural products, such as monoterpenes, displayed anti-inflammatory and anti-oxidant activities and can be used as a source of new compounds to COPD treatment. Our aim was to evaluate, in an elastase-induced pulmonary emphysema in mice, the effects of and underlying mechanisms of three related natural monoterpenes (p-cymene, carvacrol and thymol) isolated from essential oil from leaves Lippia sidoides Cham. (Verbenaceae). Methods: Mices received porcine pancreatic elastase (PPE) and were treated with p-cymene, carvacrol, thymol or vehicle 30 min later and again on 7th, 14th and 28th days. Lung inflammatory profile and histological sections were evaluated. Results: In the elastase-instilled animals, the tested monoterpenes reduced alveolar enlargement, macrophages and the levels of IL-1 beta, IL-6, IL-8 and IL-17 in bronchoalveolar lavage fluid (BALF), and collagen fibers, MMP-9 and p-65-NF-kappa B-positive cells in lung parenchyma (p < 0.05). All treatments attenuated levels of 8-iso-PGF2 alpha but only thymol was able to reduced exhaled nitric oxide (p < 0.05). Conclusion: Monoterpenes p-cymene, carvacrol and thymol reduced lung emphysema and inflammation in mice. No significant differences among the three monoterpenes treatments were found, suggesting that the presence of hydroxyl group in the molecular structure of thymol and carvacrol do not play a central role in the anti-inflammatory effects.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Laboratorio de Investigacao Medica, Hospital das Clinicas, Faculdade de Medicina, University of Sao Paulo (LIM)Univ Fed Sao Paulo, Dept Biol Sci, BR-09913030 Diadema, BrazilUniv Sao Paulo, Sch Med, Dept Med, BR-01246903 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Exact Sci & Earth, BR-09913030 Diadema, BrazilFed Univ ABC, Ctr Nat Sci & Humanities, BR-09606045 Santo Andre, SP, BrazilUniv Fed Sao Paulo, Dept Biosci, Campus Baixada Santista, BR-11015020 Santos, SP, BrazilDepartment of Biological Science, Universidade Federal de São Paulo, Diadema 09913-030, BrazilDepartment of Exact Science and Earth, Universidade Federal de São Paulo, Diadema 09913-030, BrazilDepartment of Bioscience, Federal University of São Paulo, Campus Baixada Santista, Santos 11015-020, SP, BrazilCNPq: 300546/2012-2CNPq: 304465/2012-7CNPq: 476877/2012-1CNPq: 306278/2015-4FAPESP: 2011/51739-0FAPESP: 2013/02881-4FAPESP: 2008/55359-5FAPESP: 2015/11936-2FAPESP: 2014/25689-4LIM: LIM20Web of Scienc

Evidences of Herbal Medicine-Derived Natural Products Effects in Inflammatory Lung Diseases

Pulmonary inflammation is a hallmark of many respiratory diseases such as asthma, chronic obstructive pulmonary disease (COPD), and acute respiratory syndrome distress (ARDS). Most of these diseases are treated with anti-inflammatory therapy in order to prevent or to reduce the pulmonary inflammation. Herbal medicine-derived natural products have been used in folk medicine and scientific studies to evaluate the value of these compounds have grown in recent years. Many substances derived from plants have the biological effects in vitro and in vivo, such as flavonoids, alkaloids, and terpenoids. Among the biological activities of natural products derived from plants can be pointed out the anti-inflammatory, antiviral, antiplatelet, antitumor anti-allergic activities, and antioxidant. Although many reports have evaluated the effects of these compounds in experimental models, studies evaluating clinical trials are scarce in the literature. This review aims to emphasize the effects of these different natural products in pulmonary diseases in experimental models and in humans and pointing out some possible mechanisms of action