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1.
World J Microbiol Biotechnol ; 40(5): 147, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38538981

RESUMEN

Probiotic microorganisms are used to improve the health and wellness of people and the research on this topic is of current relevance and interest. Fifty-five yeasts, coming from honeybee's ecosystem and belonging to Candida, Debaryomyces, Hanseniaspora, Lachancea, Metschnikowia, Meyerozyma, Starmerella and Zygosacchromyces genera and related different species, were evaluated for the probiotic traits. The resistance to gastrointestinal conditions, auto-aggregation, cell surface hydrophobicity or biofilm formation abilities as well as antimicrobial activity against common human pathogenic bacteria were evaluated. The safety analysis of strains was also carried out to exclude any possible negative effect on the consumer's health. The influence of proteinase treatment of living yeasts and their adhesion to Caco-2 cells were also evaluated. The greatest selection occurred in the first step of survival at the acidic pH and in the presence of bile salts, where more than 50% of the strains were unable to survive. Equally discriminating was the protease test which allowed the survival of only 27 strains belonging to the species Hanseniaspora guilliermondii, Hanseniaspora uvarum, Metschnikowia pulcherrima, Metschnikowia ziziphicola, Meyerozyma caribbica, Meyerozyma guilliermondii, Pichia kluyveri, Pichia kudriavzevii and Pichia terricola. An integrated analysis of the results obtained allowed the detection of seven yeast strains with probiotic aptitudes, all belonging to the Meyerozyma genus, of which three belonging to M. guillermondii and four belonging to M. caribbica species.


Asunto(s)
Ecosistema , Probióticos , Abejas , Animales , Humanos , Células CACO-2 , Levaduras/metabolismo , Candida
2.
Cancer Discov ; 14(2): 274-289, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-37982575

RESUMEN

Fulvestrant is used to treat patients with hormone receptor-positive advanced breast cancer, but acquired resistance is poorly understood. PlasmaMATCH Cohort A (NCT03182634) investigated the activity of fulvestrant in patients with activating ESR1 mutations in circulating tumor DNA (ctDNA). Baseline ESR1 mutations Y537S are associated with poor outcomes and Y537C with good outcomes. Sequencing of baseline and EOT ctDNA samples (n = 69) revealed 3/69 (4%) patients acquired novel ESR1 F404 mutations (F404L, F404I, and F404V), in cis with activating mutations. In silico modeling revealed that ESR1 F404 contributes to fulvestrant binding to estrogen receptor-alpha (ERα) through a pi-stacking bond, with mutations disrupting this bond. In vitro analysis demonstrated that single F404L, E380Q, and D538G models were less sensitive to fulvestrant, whereas compound mutations D538G + F404L and E380Q + F404L were resistant. Several oral ERα degraders were active against compound mutant models. We have identified a resistance mechanism specific to fulvestrant that can be targeted by treatments in clinical development. SIGNIFICANCE: Novel F404 ESR1 mutations may be acquired to cause overt resistance to fulvestrant when combined with preexisting activating ESR1 mutations. Novel combinations of mutations in the ER ligand binding domain may cause drug-specific resistance, emphasizing the potential of similar drug-specific mutations to impact the efficacy of oral ER degraders in development. This article is featured in Selected Articles from This Issue, p. 201.


Asunto(s)
Neoplasias de la Mama , ADN Tumoral Circulante , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Fulvestrant/farmacología , Fulvestrant/uso terapéutico , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , ADN Tumoral Circulante/genética , Mutación
3.
Materials (Basel) ; 16(21)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37959458

RESUMEN

The environmental impacts of cement manufacturing are becoming a real-time issue that requires attention. This paper investigates the mechanical and physical properties of mortars with finely ground sand as a substitute for cement. The experimental program consisted of three silica sands with a Blaine Specific Surface (BSS) area of 459 m2/kg, 497 m2/kg, and 543 m2/kg and four substitution ratios of 10%, 20%, 30%, and 40%. A total of 12 mixtures have been prepared and tested for comparison to the reference mortar. The pozzolanic effect of the sand was evaluated using thermogravimetric analysis (TGA). The results revealed that the fineness variation from 459 m2/kg to 543 m2/kg resulted in an increase of 20% and 30% in water absorption and compressive strength, respectively. However, increasing the substitution ratio from 10% to 40% led to a 40% decrease in mechanical strength and a 25% increase in water absorption. The statistical analysis of the results demonstrated that both factors under study influenced compressive strength and water absorption. The ANalysis of VAriance (ANOVA) confirmed that the proposed regression equations predict the experimental results. Further studies will investigate both the technical and environmental performances of cement mortars with finely ground silica sand.

4.
Heliyon ; 9(9): e19977, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809837

RESUMEN

Urban Heat Islands (UHIs) are expanding in anthropized areas, causing serious climatic consequences such as rising temperatures and citizens' discomfort. Several studies have identified and confirmed how the use of cool road pavements can mitigate and reduce the negative effects of UHIs. This study performs a microclimate simulation of San Pietro in Vincula Square in Rome through ENVI-Met software by replacing the current asphalt pavement in the parking area with a cool one. The proposed layout consists of light concrete pavers in the parking lots, parking aisles made of photovoltaic (PV) panels, and a perimeter hedge. The innovative use of PVs is analysed from the thermal and economic viewpoints alike. In the first case, its thermal characteristics like those of asphalt provide results in terms of air temperature, mean radiant temperature, and predicted mean vote close to the current ones. Furthermore, the energy analysis shows the PV's effectiveness in terms of economic impact. Indeed, the electricity produced by the proposed PV system is enough to light the area, and its surplus can power public activities such as electric vehicle charging. The initial investment would pay for itself in the 25-year service life as confirmed by the positive net present value (NPV), and the cash flow reveals a break-even point in the 15th year.

5.
Mol Ther Methods Clin Dev ; 31: 101103, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-37744006

RESUMEN

Citrullinemia type I is a rare autosomal-recessive disorder caused by deficiency of argininosuccinate synthetase (ASS1). The clinical presentation includes the acute neonatal form, characterized by ammonia and citrulline accumulation in blood, which may lead to encephalopathy, coma, and death, and the milder late-onset form. Current treatments are unsatisfactory, and the only curative treatment is liver transplantation. We permanently modified the hepatocyte genome in lethal citrullinemia mice (Ass1fold/fold) by inserting the ASS1 cDNA into the albumin locus through the delivery of two AAV8 vectors carrying the donor DNA and the CRISPR-Cas9 platform. The neonatal treatment completely rescued mortality ensuring survival up to 5 months of age, with plasma citrulline levels significantly decreased, while plasma ammonia levels remained unchanged. In contrast, neonatal treatment with a liver-directed non-integrative AAV8-AAT-hASS1 vector failed to improve disease parameters. To model late-onset citrullinemia, we dosed postnatal day (P) 30 juvenile animals using the integrative approach, resulting in lifespan improvement and a minor reduction in disease markers. Conversely, treatment with the non-integrative vector completely rescued mortality, reducing plasma ammonia and citrulline to wild-type values. In summary, the integrative approach in neonates is effective, although further improvements are required to fully correct the phenotype. Non-integrative gene therapy application to juvenile mice ensures a stable and very efficient therapeutic effect.

6.
Int J Mol Sci ; 24(17)2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37685876

RESUMEN

Recurrent pregnancy loss (RPL) refers to two or more miscarriages before 20 weeks gestation. Its prevalence is 1-2%; its pathogenesis remains unexplained in more than 50% of cases, in which the cause is thought to be abnormal immune activity during placentation leading to a lack of pregnancy-induced immune tolerance. It is unknown whether immune activity is deranged in the endometrium of women with RPL. We studied the gene expression and the quantitative tissue protein levels of three immune checkpoints (CD276, which enhances cytotoxic T-cell activity, cytotoxic T-lymphocyte-associated antigen-4 [CTL-4], which reduces Th1 cytokine production, and lymphocyte activation gene-3 [LAG-3], which shows suppressive activity on Tregs and CD4+ T-cells) in endometrial samples from 27 women with unexplained RPL and in 29 women with dysfunctional uterine bleeding and previous uneventful pregnancies as controls. RNA isolation, real-time PCR, protein isolation, and ELISA were performed. CD276 gene expression and protein tissue levels were significantly lower in the endometrium of the RPL group than in the controls, whereas both CTL-4 and LAG-3 were significantly higher. This difference suggests defective endometrial immune regulation and overactivation of immune response in women with a history of RPL, at least in relation to controls with dysfunctional uterine bleeding and previous normal reproductive history.


Asunto(s)
Aborto Habitual , Metrorragia , Embarazo , Femenino , Humanos , Genes Reguladores , Factores de Transcripción , Abatacept , Aborto Habitual/genética , Antígenos B7
7.
Clin Cancer Res ; 29(23): 4751-4759, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37773077

RESUMEN

PURPOSE: Approximately 10% to 15% of triple-negative breast cancers (TNBC) have deleterious mutations in BRCA1 and BRCA2 and may benefit from PARP inhibitor treatment. PARP inhibitors may also increase exogenous replication stress and thereby increase sensitivity to inhibitors of ataxia telangiectasia and Rad3-related (ATR) protein. This phase II study examined the activity of the combination of PARP inhibitor, olaparib, and ATR inhibitor, ceralasertib (AZD6738), in patients with advanced TNBC. PATIENTS AND METHODS: Patients with TNBC on most recent biopsy who had received 1 or 2 lines of chemotherapy for advanced disease or had relapsed within 12 months of (neo)adjuvant chemotherapy were eligible. Treatment was olaparib 300 mg twice a day continuously and celarasertib 160 mg on days 1-7 on a 28-day cycle until disease progression. The primary endpoint was confirmed objective response rate (ORR). Tissue and plasma biomarker analyses were preplanned to identify predictors of response. RESULTS: 70 evaluable patients were enrolled. Germline BRCA1/2 mutations were present in 10 (14%) patients and 3 (4%) patients had somatic BRCA mutations. The confirmed ORR was 12/70; 17.1% (95% confidence interval, 10.4-25.5). Responses were observed in patients without germline or somatic BRCA1/2 mutations, including patients with mutations in other homologous recombination repair genes and tumors with functional homologous recombination deficiency by RAD51 foci. CONCLUSIONS: The response rate to olaparib and ceralasertib did not meet prespecified criteria for activity in the overall evaluable population, but responses were observed in patients who would not be expected to respond to olaparib monotherapy.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama Triple Negativas , Humanos , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Proteína BRCA1/genética , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Proteína BRCA2/genética , Antineoplásicos/uso terapéutico , Ftalazinas/efectos adversos
8.
Heliyon ; 9(7): e18378, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37539140

RESUMEN

The topographical features of a site and the anthropogenic artefacts inside and outside the airport boundaries influence the infrastructure use. Objects penetrating the obstacle limitation surfaces (OLS) or standing outside those surfaces have to be mapped and risk-assessed because they could be a hazard to air navigation. This study aims to quantify the risk of collision between aircraft and obstacles in the airspace. There are no available procedures in the literature: the authors supposed that the obstacle type and the examined OLS affect the collision risk. The proposed risk values and amplification factors derive from interviews with technicians. The methodology has been implemented in an existing airport with 589 penetrating obstacles: the results highlight that 69.8% of obstacles imply a negligible risk, and 3.7% require further analyses by the competent aviation authority. In this study, buildings and pylons penetrating the Transitional Surface are the most hazardous obstacles.

9.
Sensors (Basel) ; 23(13)2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37447710

RESUMEN

Repairing potholes is a task for municipalities to prevent serious road user injuries and vehicle damage. This study presents a low-cost, high-performance pothole monitoring system to maintain urban roads. The authors developed a methodology based on photogrammetry techniques to predict the pothole's shape and volume. A collection of overlapping 2D images shot by a Raspberry Pi Camera Module 3 connected to a Raspberry Pi 4 Model B has been used to create a pothole 3D model. The Raspberry-based configuration has been mounted on an autonomous and remote-controlled robot (developed in the InfraROB European project) to reduce workers' exposure to live traffic in survey activities and automate the process. The outputs of photogrammetry processing software have been validated through laboratory tests set as ground truth; the trial has been conducted on a tile made of asphalt mixture, reproducing a real pothole. Global Positioning System (GPS) and Geographical Information System (GIS) technologies allowed visualising potholes on a map with information about their centre, volume, backfill material, and an associated image. Ten on-site tests validated that the system works in an uncontrolled environment and not only in the laboratory. The results showed that the system is a valuable tool for monitoring road potholes taking into account construction workers' and road users' health and safety.


Asunto(s)
Imagenología Tridimensional , Programas Informáticos , Humanos , Imagenología Tridimensional/métodos , Ciudades , Fotogrametría
10.
Int J Mol Sci ; 24(11)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37298167

RESUMEN

Eosinophilic/T-cell chorionic vasculitis (ETCV) is an idiopathic lesion composed of eosinophils, CD3+ T lymphocytes, and histiocytes. In twins, ETCV may affect only one chorionic plate, a feature defined as "discordant". We present a case of ETCV discordance in a diamniotic dichorionic placenta at 38 weeks of gestation, in which the female twin was small for gestational age, weighing 2670 g (25th percentile). The corresponding placental territory presented ETCV in two close chorionic vessels with concordance of the fetal inflammatory response. Immunohistochemistry showed an abundance of CD3+/CD4+/CD25+T lymphocytes, CD68 PG M1+ macrophages, and scattered CD8+ T cells with focal TIA-1 positivity. Granzyme B, CD20 B lymphocytes, and CD56 natural killer cells were negative. High-grade villitis of unknown etiology (VUE) was additionally found and displayed comparable ETCV findings, except for an equivalent ratio of CD4+/CD8+ T cells, but TIA-1 was focally expressed. VUE was associated with chronic histiocytic intervillositis (CHI). The combination of ETCV, VUE, and CHI may have been responsible for reduced fetal growth. Concordance was observed in the ETCV and TIA-1 expression, both in ETCV and in VUE, which is a maternal response. These findings may suggest a common antigen or chemokine pathway to which both mother and fetus accordingly responded.


Asunto(s)
Enfermedades Placentarias , Vasculitis , Femenino , Embarazo , Humanos , Placenta/metabolismo , Enfermedades Placentarias/metabolismo , Corion/metabolismo , Linfocitos T CD8-positivos , Vellosidades Coriónicas/metabolismo
11.
Materials (Basel) ; 16(4)2023 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-36836965

RESUMEN

Environmental safeguards promote innovative construction technologies for sustainable pavements. On these premises, this study investigated four hot mix asphalt (HMA) mixtures-i.e., A, B, C, and D-for the railway sub-ballast layer with 0%, 10%, 20%, and 30% reclaimed asphalt pavement (RAP) by total aggregate mass and a rejuvenator additive, varying the bitumen content between 3.5% and 5.0%. Both Marshall and gyratory compactor design methods have been performed, matching the stability, indirect tensile strength, and volumetric properties of each mixture. Dynamic stiffness and fatigue resistance tests provided mechanical performances. Laboratory results highlighted that the RAP and the rejuvenator additive increase the mechanical properties of the mixtures. In addition, the comparative analysis of production costs revealed up to 20% savings as the RAP content increased, and the life cycle impact analysis (LCIA) proved a reduction of the environmental impacts (up to 2% for resource use-fossils, up to 7% for climate change, and up to 13% for water use). The experimental results confirm that HMA containing RAP has mechanical performances higher than the reference mixture with only virgin raw materials. These findings could contribute to waste management and reduce the environmental and economic costs, since the use of RAP in the sub-ballast is not, so far, provided in the Italian specifications for railway construction.

12.
Transp Res Interdiscip Perspect ; 15: 100646, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35782786

RESUMEN

Background: The rapid outbreak of Coronavirus disease 2019 (COVID-19) has posed several challenges to the scientific community. The goal of this paper is to investigate the spread of COVID-19 in Northern Italy during the so-called first wave scenario and to provide a qualitative comparison with the local highway net. Methods: Fixed a grid of days from February 27, 2020, the cumulative numbers of infections in each considered province have been compared to sequences of thresholds. As a consequence, a time-evolving classification of the state of danger in terms of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, in view of the smallest threshold overtaken by this comparison, has been obtained for each considered province. The provinces with a significant amount of cases have then been collected into matrices containing only the ones featuring a significant amount of cases. Results: The time evolution of the classification has then been qualitatively compared to the highway network, to identify similarities and thus linking the rapid spreading of COVID-19 and the highway connections. Conclusions: The obtained results demonstrate how the proposed model properly fits with the spread of COVID-19 along with the Italian highway transport network and could be implemented to analyze qualitatively other disease transmissions in different contexts and time periods.

13.
Trials ; 23(1): 372, 2022 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-35526005

RESUMEN

BACKGROUND: Platform trial designs are used increasingly in cancer clinical research and are considered an efficient model for evaluating multiple compounds within a single disease or disease subtype. However, these trial designs can be challenging to operationalise. The use of platform trials in oncology clinical research has increased considerably in recent years as advances in molecular biology enable molecularly defined stratification of patient populations and targeted therapy evaluation. Whereas multiple separate trials may be deemed infeasible, platform designs allow efficient, parallel evaluation of multiple targeted therapies in relatively small biologically defined patient sub-populations with the promise of increased molecular screening efficiency and reduced time for drug evaluation. Whilst the theoretical efficiencies are widely reported, the operational challenges associated with these designs (complexity, cost, regulatory, resource) are not always well understood. MAIN: In this commentary, we describe our practical experience of the implementation and delivery of the UK plasmaMATCH trial, a platform trial in advanced breast cancer, comprising an integrated screening component and multiple parallel downstream mutation-directed therapeutic cohorts. plasmaMATCH reported its primary results within 3 years of opening to recruitment. We reflect on the operational challenges encountered and share lessons learnt to inform the successful conduct of future trials. Key to the success of the plasmaMATCH trial was well co-ordinated stakeholder engagement by an experienced clinical trials unit with expert methodology and trial management expertise, a federated model of clinical leadership, a well-written protocol integrating screening and treatment components and including justification for the chosen structure and intentions for future adaptions, and an integrated funding model with streamlined contractual arrangements across multiple partners. Findings based on our practical experience include the importance of early engagement with the regulators and consideration of a flexible resource infrastructure to allow adequate resource allocation to support concurrent trial activities as adaptions are implemented in parallel to the continued management of patient safety and data quality of the ongoing trial cohorts. CONCLUSION: Platform trial designs allow the efficient reporting of multiple treatment cohorts. Operational challenges can be overcome through multidisciplinary engagement, streamlined contracting processes, rationalised protocol and database design and appropriate resourcing.


Asunto(s)
Neoplasias de la Mama , Ensayos Clínicos Fase II como Asunto , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Estudios de Cohortes , Manejo de Datos , Femenino , Humanos , Proyectos de Investigación
14.
Biomedicines ; 10(3)2022 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-35327436

RESUMEN

Despite Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) -induced Oxidative Stress (OxS) being well documented in different organs, the molecular pathways underlying placental OxS in late-pregnancy women with SARS-CoV-2 infection are poorly understood. Herein, we performed an observational study to determine whether placentae of women testing positive for SARS-CoV-2 during the third trimester of pregnancy showed redox-related alterations involving Catalase (CAT) and Superoxide Dismutase (SOD) antioxidant enzymes as well as placenta morphological anomalies relative to a cohort of healthy pregnant women. Next, we evaluated if placental redox-related alterations and mitochondria pathological changes were correlated with the presence of maternal symptoms. We observed ultrastructural alterations of placental mitochondria accompanied by increased levels of oxidative stress markers Thiobarbituric Acid Reactive Substances (TBARS) and Hypoxia Inducible Factor-1 α (HIF-1α) in SARS-CoV-2 women during the third trimester of pregnancy. Importantly, we found an increase in placental CAT and SOD antioxidant enzymes accompanied by physiological neonatal outcomes. Our findings strongly suggest a placenta-mediated OxS inhibition in response to SARS-CoV-2 infection, thus contrasting the cytotoxic profile caused by Coronavirus Disease 2019 (COVID-19).

15.
Int J Mol Sci ; 23(3)2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35163594

RESUMEN

We tested the pro-angiogenic and anti-inflammatory effects of human placenta-derived mesenchymal stromal cells (hPDMSCs)-derived conditioned media (CM) on a mouse model of preeclampsia (PE), a severe human pregnancy-related syndrome characterized by maternal hypertension, proteinuria, endothelial damage, inflammation, often associated with fetal growth restriction (FGR). At d11 of pregnancy, PE was induced in pregnant C57BL/6N mice by bacterial lipopolysaccharide (LPS) intravenous injection. At d12, 300 µL of unconditioned media (control group) or 300 µL PDMSCs-CM (CM group) were injected. Maternal systolic blood pressure was measured from 9 to 18 days of pregnancy. Urine protein content were analyzed at days 12, 13, and 17 of pregnancy. At d19, mice were sacrificed. Number of fetuses, FGR, fetal reabsorption, and placental weight were evaluated. Placentae were analyzed for sFlt-1, IL-6, and TNF-α gene and protein expressions. No FGR and/or reabsorbed fetuses were delivered by PDMSCs-CM-treated PE mice, while five FGR fetuses were found in the control group accompanied by a lower placental weight. PDMSCs-CM injection significantly decreased maternal systolic blood pressure, proteinuria, sFlt-1, IL-6, and TNF-α levels in PE mice. Our data indicate that hPDMSCs-CM can reverse PE-like features during pregnancy, suggesting a therapeutic role for hPDMSCs for the treatment of preeclampsia.


Asunto(s)
Lipopolisacáridos/toxicidad , Células Madre Mesenquimatosas/metabolismo , Placenta/metabolismo , Preeclampsia/metabolismo , Animales , Medios de Cultivo Condicionados/farmacología , Modelos Animales de Enfermedad , Femenino , Ratones , Preeclampsia/inducido químicamente , Embarazo
16.
Materials (Basel) ; 16(1)2022 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-36614514

RESUMEN

Road asphalt pavements cover a high percentage of urban size and contribute to heat islands. This study proposed a new method to cool asphalt pavement by incorporating a kind of hybrid mineral filler (HMF) with high emissivity into a reference asphalt mixture prepared with limestone mineral filler (LMF). The physical, emissive, solar reflective, and rheological properties of asphalt mastic and the thermal performances of asphalt mixture were covered to investigate the possibility of the proposed strategy. From Fourier transform infrared spectrum test, it can be found that HMF was physically blended with asphalt. The emissivity results show that HMF increased the emissivity of asphalt mastic from 0.9204 to 0.9820. The asphalt mastic containing HMF had similar solar reflectance with the control one. In addition, HMF could enhance the rutting resistance of asphalt mastic according to the results of multiple stress creep recovery tests. When HMF replaced LMF, the thermal conductivity of the asphalt mixture with HMF increased by 0.26 W/(m·K) (the reference value was 1.72 W/(m·K)). The combined effect of high emissivity and thermal conductivity led to a lower surface temperature (i.e., -5.4 °C) in the tests. The results of this study demonstrate that HMF is a potential material to cool asphalt pavements.

17.
Artículo en Inglés | MEDLINE | ID: mdl-34948720

RESUMEN

Cool pavements are reflective and/or permeable pavements that improve microclimate of urban areas where heat islands cause discomfort to citizens. Stone pavements lower surface temperatures and reduce the amount of heat absorbed. This study assessed, using ENVI-met 4.3 LITE software, how air temperature and predicted mean vote depend on physical properties of the road pavement. A comparative microclimatic analysis was implemented on a rectangular square in Rome (Italy) in the summer, paved in three different ways: asphalt, traditional sampietrini, and permeable sampietrini. The model considered local weather parameters, surrounding fabric, and vegetation to give reliable results in terms of numerical and graphical output using the application tool Leonardo. The tested pavement types affected air temperature during the day, but did not influence this variable in the early morning. Permeable sampietrini pavement was more effective than traditional sampietrini pavement in reducing air temperature compared to the current asphalt surface. The road pavement did not, however, affect human comfort in terms of predicted mean vote. The obtained results are useful for further investigation of parameters that could modify the microclimatic conditions of urban areas.


Asunto(s)
Calor , Microclima , Ciudades , Frío , Humanos , Temperatura
18.
Materials (Basel) ; 14(23)2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34885383

RESUMEN

The Cement Grouted Bituminous Mix (CGBM) is an innovative material that could be used to build airport pavements subjected to heavy concentrated loads or fuel and solvent leaks. CGBM is composed of a porous asphalt clogged with an expansive cement mixture, which fills the asphalt voids. This paper focuses on two airport pavements (i.e., a taxiway and a helipad one) to be paved in an Italian airport. For each surface, the construction and maintenance costs of a CGBM pavement and a traditional flexible pavement have been compared. The pavements should bear different traffic loads, while the weather, subgrade, and materials are the same: the fatigue and rutting verification gives structures whose cost analysis leads to different results. The CGBM solution for the taxiway has a cost comparable to that of the equivalent traditional flexible pavement (i.e., 73.87 €/m2 vs. 73.20 €/m2 during the service life). On the other hand, the overall discounted cost of the helipad surface paved with CGBM is higher than that obtained for the traditional pavement (i.e., 82.4 €/m2 vs. 67.5 €/m2). Therefore, the study demonstrates that the economic opportunity of CGBM solutions strongly depends on traffic loads.

19.
Transp Res Interdiscip Perspect ; 12: 100503, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34849483

RESUMEN

The world is facing new challenges due to the SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2) virus outbreak identified in Wuhan, China in December 2019. The aim of this paper is to investigate and discuss how cities are being managed in the anti-pandemic "new normal". And this in light of unexpected phenomena such as: the on-going modal shift from public transport to private modes vs the new momentum gained by walking, and social lifestyles dictated by confinement first and now by unregulated behavior, also affecting land use. Add to this unpreparedness of pre-pandemic transport policies and the new emerging opportunities; the fresh directions for research and development, for example in the field of urban mobility management. With the additional goal to contribute to further advance the research, the paper also clearly shows that the crisis can be overcome only by considering different fields of action and by considering our common past.

20.
Sensors (Basel) ; 21(20)2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34696010

RESUMEN

Airport pavements should ensure regular and safe movements during their service life; the management body has to monitor the functional and structural characteristics, and schedule maintenance work, balancing the often conflicting goals of safety, economic and technical issues. This paper presents a remote monitoring system to evaluate the structural performance of a runway composed of concrete thresholds and a flexible central runway. Thermometers, strain gauges, and pressure cells will be embedded at different depths to continuously monitor the pavement's response to traffic and environmental loads. An innovative system allows data acquisition and processing with specific calculation models, in order to inform the infrastructure manager, in real time, about the actual conditions of the pavement. In this way, the authors aim to develop a system that provides useful information for the correct implementation of an airport pavement management system (APMS) based on real-life data. Indeed, it permits comprehensive monitoring functions to be performed, based on the embedded sensing network.


Asunto(s)
Estrés Mecánico
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