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1.
Materials (Basel) ; 17(18)2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39336200

RESUMO

Freshwater resources are scarce in coastal areas, and using seawater as mixing water can alleviate the scarcity of freshwater resources. However, the presence of chloride ions in seawater affects the generation of hydration products and the durability of concrete structures. In order to investigate the effect of hydrated calcium silicate (C-S-H) gel and calcium hydroxide (CH) generation in seawater-mixed cement pastes under 50 °C curing, their microscopic morphology was investigated using differential scanning calorimetry analysis, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The relationship between the amount of C-S-H gel and CH production and the amount of chloride ion dosing, fly ash dosing, and the age of curing were investigated. The degree of influence between hydration products and influencing factors was analyzed using the grey correlation analysis. It was shown that 50 °C curing promoted the hydration reaction and generated more hydration products compared with ASTM standard. The content of C-S-H gel and CH increased with chloride dosage. The content of C-S-H gel increased by 13.5% under 50 °C curing compared with the control group at a chloride dosage of 1.3%. Fly ash is rich in active SiO2 and AI2O3, and other components, which can react with Ca(OH)2 generated by cement hydration and then generate C-S-H gel. With the increase of fly ash, the content of C-S-H gel also increases, but the CH content decreases. When 25% of fly ash was doped under 50 °C curing, the C-S-H gel content increased by 5.02% compared to the control group. The CH content decreased by 31.8% compared to the control group. With the growth of the maintenance age, the hydration reaction continues, the generation of C-S-H gel and CH will continue to increase, and their microstructures will become denser. C-S-H gel and CH content increased the most by raising the curing temperature at 7 days of curing, increasing by 10.11% and 22.62%, respectively. C-S-H gel and CH content had the highest gray relation with fly ash dosing. Chloride dosage and age of maintenance had the highest correlation with CH content at room temperature maintenance of 0.788 and 0.753, respectively.

2.
Materials (Basel) ; 17(16)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39203127

RESUMO

Mixing cement with seawater will cause the hydration process of cement to be different from that of ordinary cement, which will significantly affect cement's mechanical properties and durability. This article investigates the effects of chloride ion concentration, curing temperature, and nano-metakaolin content on the evolution process of Friedel's salts and ettringite (AFt) crystals in cement pastes. The study was conducted using X-ray diffraction (XRD), thermal analysis (TG), scanning electron microscopy (SEM), and mercury-intrusion porosimetry (MIP). The results show that chlorine salt can increase the production of Friedel's salt and ettringite, and the delayed AFt production increases by up to 27.95% after the addition of chlorine salt, which has an adverse effect on cement-based materials. Increasing the curing temperature and increasing the nano-metakaolin dosage increased the generation of Friedel's salt and decreased the delayed AFt generation, which resulted in a decrease in the length and diameter of the AFt crystals. After 28 days of high-temperature curing and the addition of nano-metakaolin, Friedel's salt production increased by 13.40% and 14.34%, respectively, and ettringite production decreased by 9.68% and 7.93%, respectively. Increasing the curing temperature and adding nano-metakaolin can reduce the adverse effect of delayed ettringite increases due to chloride ion binding.

3.
Sci Total Environ ; 925: 171794, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508247

RESUMO

Given the issues related to poor hydration activity, long setting time and low early strength of industrial by-product fluorogypsum (FG), the composite modifiers (Na2SO4 and NaNO2) were utilized to enhance its reactivity. The investigation of the mechanism involved the utilization of contemporary analytical methods, including X-ray diffraction (XRD), 1H low-field nuclear magnetic resonance (NMR), and Scanning electron microscope and Energy Dispersive Spectrometer (SEM-EDS). The results demonstrated that the incorporation of modifiers significantly enhanced both the hydration rate and activity of fluorogypsum. The optimum concentration of the composite modifier was found to be 1.5 wt% Na2SO4 and 0.5 wt% NaNO2. The addition of modifiers (1.5 wt% Na2SO4 and 0.5 wt% NaNO2) significantly shortens the setting time of FG paste, reducing it by approximately 500 min compared to the control sample. After 28 days of curing, the flexural strength and compressive strength of the fluorogypsum sample containing modifiers (1.5 wt% Na2SO4 and 0.5 wt% NaNO2) increased by 55.5 % (reaching 4.2 MPa) and 31.5 % (reaching 37.6 MPa), respectively. The modifiers facilitate the transformation from anhydrite (CaSO4, AH) to dihydrate gypsum (CaSO4·2H2O, DH). Both NaNO2 and Na2SO4 alter the growth rates of different crystal axes during DH crystal growth, transforming them into prismatic and needle-shaped DH. The prismatic and needle-shaped DH crystals were arranged in layers, resulting in a compact structure with low hole content and few pores, which led to increased density of the hardened paste and higher strength. The current study provides evidence that the inclusion of composite modifiers greatly improves the activity of FG, making it more efficient in the field of building materials.

4.
Sci Adv ; 10(10): eadj3460, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38446893

RESUMO

We examine the characteristics and causes of southeast Australia's Tinderbox Drought (2017 to 2019) that preceded the Black Summer fire disaster. The Tinderbox Drought was characterized by cool season rainfall deficits of around -50% in three consecutive years, which was exceptionally unlikely in the context of natural variability alone. The precipitation deficits were initiated and sustained by an anomalous atmospheric circulation that diverted oceanic moisture away from the region, despite traditional indicators of drought risk in southeast Australia generally being in neutral states. Moisture deficits were intensified by unusually high temperatures, high vapor pressure deficits, and sustained reductions in terrestrial water availability. Anthropogenic forcing intensified the rainfall deficits of the Tinderbox Drought by around 18% with an interquartile range of 34.9 to -13.3% highlighting the considerable uncertainty in attributing droughts of this kind to human activity. Skillful predictability of this drought was possible by incorporating multiple remote and local predictors through machine learning, providing prospects for improving forecasting of droughts.


Assuntos
Mudança Climática , Secas , Humanos , Austrália , Temperatura Baixa , Aprendizado de Máquina
5.
Sci Rep ; 13(1): 21578, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062087

RESUMO

The cool-season (May to October) rainfall decline in southwestern Australia deepened during 2001-2020 to become 20.5% less than the 1901-1960 reference period average, with a complete absence of very wet years (i.e., rainfall > 90th percentile). CMIP5 and CMIP6 climate model simulations suggest that approximately 43% of the observed multi-decadal decline was externally-forced. However, the observed 20-year rainfall anomaly in 2001-2020 is outside the range of both preindustrial control and historical simulations of almost all climate models used in this study. This, and the fact that the models generally appear to simulate realistic levels of decadal variability, suggests that 43% might be an underestimate. A large ensemble from one model exhibits drying similar to the observations in 10% of simulations and suggests that the external forcing contribution is indeed larger (66%). The majority of models project further drying over the twenty-first century, even under strong cuts to greenhouse gas emissions. Under the two warmest scenarios, over 70% of the late twenty-first century years are projected to be drier than the driest year simulated during the 1901-1960 period. Our results suggest that few, if any, very wet years will occur during 2023-2100, even if strong cuts to global emissions are made.

6.
Med Sci (Basel) ; 11(3)2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37755163

RESUMO

BACKGROUND: Accurate dosimetry is crucial in radiotherapy to ensure optimal radiation dose delivery to the tumor while sparing healthy tissues. Traditional dosimetry techniques using homogeneous phantoms may not accurately represent the complex anatomical variations in cervical cancer patients, highlighting the need to compare dosimetry results obtained from different phantom models. PURPOSE: The aim of this study is to design and evaluate an anthropomorphic heterogeneous female pelvic (AHFP) phantom for radiotherapy quality assurance in cervical cancer treatment. MATERIALS AND METHOD: Thirty RapidArc plans designed for cervical cancer patients were exported to both the RW3 homogeneous phantom and the anthropomorphic heterogeneous pelvic phantom. Dose calculations were performed using the anisotropic analytic algorithm (AAA), and the plans were delivered using a linear accelerator (LA). Dose measurements were obtained using a 0.6 cc ion chamber. The percentage (%) variation between planned and measured doses was calculated and analyzed. Additionally, relative dosimetry was performed for various target locations using RapidArc and IMRT treatment techniques. The AHFP phantom demonstrated excellent agreement between measured and expected dose distributions, making it a reliable quality assurance tool in radiotherapy. RESULTS: The results reveal that the percentage variation between planned and measured doses for all RapidArc quality assurance (QA) plans using the AHFP phantom is 10.67% (maximum value), 2.31% (minimum value), and 6.89% (average value), with a standard deviation (SD) of 2.565 (t = 3.21604, p = 0.001063). Also, for the percentage of variation between homogeneous and AHFP phantoms, the t-value is -11.17016 and the p-value is <0.00001. The result is thus significant at p < 0.05. We can see that the outcomes differ significantly due to the influence of heterogeneous media. Also, the average gamma values in RapidArc plans are 0.29, 0.32, and 0.35 (g ≤ 1) and IMRT plans are 0.45, 0.44, and 0.42 (g ≤ 1) for targets 1, 2, and 3, respectively. CONCLUSION: The AHFP phantom results show more dose variability than homogenous phantom outcomes. Also, the AHFP phantom was found to be suitable for QA evaluation.


Assuntos
Radioterapia (Especialidade) , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/radioterapia , Radiometria , Algoritmos , Anisotropia
7.
Trop Ecol ; : 1-11, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37362779

RESUMO

Associated with farming practices (between 300 and 2000 m elevations), human-ignited small, and patchy surface forest fires occur almost every year in Uttarakhand (between 28°43`- 31°27` N and 77°34`- 81°02`E; area 51,125 km2), a Himalayan state of India. Using fire incidence data of 19 years (2002-2020) generated by MODIS, we analysed the factors which drive temporal and spatial patterns of fire in the region. The fire incidence data were organized by 24 forest divisions, the unit of state forest management and administration. The standardized regression model showed that pre-monsoon temperature (March to May or mid-June), proportional area of the forest division under chir pine (Pinus roxburghii) forest (positive effect), and pre-monsoon and winter precipitation (negative effect) accounted for 56% of the variance in fire incidence density (FID). The pre-monsoon temperature (warmer) and precipitation (lower) were significantly different in 2009, 2012, 2016 and 2019, the years with high FID (average 54.9 fire/100 km2) than the rest of years with low FID (average 20.9 fire/100 km2). During the two decades of warming, high FID (> 30 incidence per year /100 km2) occurred after every three to four years, and fire peaks tended to increase with time. The study suggests that effective fire management can be attained by improving pre-monsoon precipitation forecasting and targeting forest compartments with a higher occurrence of chir pine and fire-vulnerable oaks. Furthermore, since fires are human-ignited, periodical analysis of changes in population distribution and communities' dependence on forests would need to be conducted. Supplementary Information: The online version contains supplementary material available at 10.1007/s42965-023-00306-9.

8.
Polymers (Basel) ; 15(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37376248

RESUMO

Reinforced concrete structures in the marine environment face serious corrosion risks. Coating protection and adding corrosion inhibitors are the most economical and effective methods. In this study, a nano-composite anti-corrosion filler with a mass ratio of CeO2:GO = 4:1 was prepared by hydrothermally growing cerium oxide on the surface of graphene oxide. The filler was mixed with pure epoxy resin at a mass fraction of 0.5% to prepare a nano-composite epoxy coating. The basic properties of the prepared coating were evaluated from the aspects of surface hardness, adhesion grade, and anti-corrosion performance on Q235 low carbon steel subjected to simulated seawater and simulated concrete pore solutions. Results showed that after 90 days of service, the corrosion current density of the nanocomposite coating mixed with corrosion inhibitor was the lowest (Icorr = 1.001 × 10-9 A/cm2), and the protection efficiency was up to 99.92%. This study provides a theoretical foundation for solving the corrosion problem of Q235 low carbon steel in the marine environment.

9.
Heliyon ; 9(3): e14596, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36950562

RESUMO

Economic development fosters a favorable ecosystem for entrepreneurs. Economic development and entrepreneurship ecosystem have positive causality with each other. Subsequently, economic development is also a useful determinant of the entrepreneurship ecosystem and vice-versa. The entrepreneurship ecosystem cannot be nurtured without financial development. However, limited studies have observed the causal association between an entrepreneurship ecosystem and financial inclusion. As financial development has a vital contribution to increasing the entrepreneurship ecosystem, this study examines the cause-and-effect relationship between entrepreneurship ecosystem and financial inclusion across countries. The regression coefficients of selected independent variables are estimated through robust empirical models. For said investigation, the global financial inclusion index and global entrepreneurship ecosystem index score were used as proxy variables for financial inclusion and entrepreneurship ecosystem, respectively in regression analysis. The empirical findings revealed that financial inclusion can be improved with an increase in entrepreneurship ecosystem, economic development, ease of doing business, employers, foreign direct investment net inflow, use of internet facilities, and wage and salaried workers. In the same way, entrepreneurship ecosystem can also be nurtured with financial inclusion, economic development, trade openness, ease of doing business, total employers, use of internet facilities and wage and salaried workers increase. The empirical results also inferred that entrepreneurship ecosystem, gross domestic per capita, foreign direct investment net inflow, ease of doing business, employer's start-up procedures to register a business and wages and salaries are important indicators to expand financial inclusion. Further, the results claimed that entrepreneurship ecosystem and financial inclusion are complementary to each other.

10.
Environ Monit Assess ; 195(2): 258, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36595133

RESUMO

The difference in maintaining a safety margin with regard to hydraulic conductance between pine and oak species influences their distribution in a region. Chir pine (Pinus roxburghii) and banj oak (Quercus leucotrichophora) are the principal species of Central Himalayan forests between 1000 and 2000 m elevations. Nearly 80% of annual precipitation of ~ 1400 mm in the region occurs during monsoon, from mid-June to September, whereafter droughts of varying length and intensity are common. The main objective of the study is to find out the responses of these two evergreen tree species to pre-monsoon (March to mid-June) water stress and topographical heterogeneity that occur in Central Himalaya. We measured soil and tree water potential and osmotic adjustment across five seasons on three slope positions, namely, hill base, mid-slope, and hill top, on north and south slope aspects. Chir pine showed an early response to pre-monsoon drought by restraining daily change in Ψ to 0.89 MPa, while predawn Ψ (ΨPD) was still moderate (isohydric tendency). In contrast, the daily reduction in Ψ of banj oak kept on increasing up to 1.49 MPa, despite severely low ΨPD (anisohydric tendency). In both tree species, Ψ was invariably lower on south aspect than north aspect and declined from hill base to hill top. Such responses to slope aspect and position, however, were relatively less apparent in chir pine, which tended to maintain a wide safety margin when under stress. As for soil Ψ, banj oak site retained monsoon rainwater more effectively than chir pine.


Assuntos
Pinus , Quercus , Quercus/fisiologia , Secas , Monitoramento Ambiental , Árvores/fisiologia , Solo
11.
Indian J Ophthalmol ; 70(11): 3849-3852, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36308110

RESUMO

Purpose: The study was conducted to evaluate efficacy of intracameral lidocaine hydrochloride 1% and tropicamide injection 0.02% for anaesthesia and mydriasis in manual small-incision cataract surgery (MSICS) and to report any adverse drug reaction. Methods: This was a randomized, prospective, observational study on 32 participants that took place from October 2021 to March 2022 (6 months). Patients between age group 40-75 year with nuclear sclerosis cataract and pupil diameter >6 mm in preoperative evaluation were included in the study. Patients with pseudoexfoliation, rigid pupil, senile miosis, history of uveitis, ocular trauma, recent ocular infections, with known allergy to tropicamide, all types of glaucoma were excluded from the study. Results: Thirty-two eyes with nuclear sclerosis cataract who underwent MSICS were studied. Fixed dose combination of 2 ml phenyl epinephrine (0.31%), tropicamide (0.02%), and lidocaine (1%) intracamerally was used for mydriasis and analgesia. More than 7 mm pupillary dilatation was achieved within 20 seconds of injection in 29 cases (90.6%). Mild pain and discomfort was noted in 12 cases (37.5%). Postoperative day 1 unaided visual acuity was in the range of 6/18-6/12 for all patients and grade 1 iritis was seen in 7 cases (21.8%) which was self-limiting. No adverse event like corneal decompensation or TASS were noted. Conclusion: Thus, Intracameral injection of mydriatic provides rapid and sustainable mydriasis and analgesia for manual SICS.


Assuntos
Catarata , Midríase , Facoemulsificação , Humanos , Tropicamida/efeitos adversos , Lidocaína , Midríase/induzido quimicamente , Estudos Prospectivos , Esclerose/induzido quimicamente , Midriáticos , Pupila , Catarata/induzido quimicamente , Fenilefrina/efeitos adversos
12.
PeerJ ; 10: e14277, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312761

RESUMO

Background: Large-scale changes in habitat conditions due to human modifications and climate change require management practices to consider how species communities can alter amidst these changes. Understanding species interactions across the gradient of space, anthropogenic pressure, and season provide the opportunity to anticipate possible dynamics in the changing scenarios. We studied the interspecific interactions of carnivore species in a high-altitude ecosystem over seasonal (summer and winter) and resource gradients (livestock grazing) to assess the impact of changing abiotic and biotic settings on coexistence. Methods: The study was conducted in the Upper Bhagirathi basin, Western Himalaya, India. We analyzed around 4 years of camera trap monitoring data to understand seasonal spatial and temporal interactions of the snow leopard with common leopard and woolly wolf were assessed in the greater and trans-Himalayan habitats, respectively. We used two species occupancy models to assess spatial interactions, and circadian activity patterns were used to assess seasonal temporal overlap amongst carnivores. In addition, we examined scats to understand the commonalities in prey selection. Results: The result showed that although snow leopard and wolves depend on the same limited prey species and show high temporal overlap, habitat heterogeneity and differential habitat use facilitate co-occurrence between these two predators. Snow leopard and common leopard were spatially independent in the summer. Conversely, the common leopard negatively influences the space use of snow leopard in the winter. Limited prey resources (lack of livestock), restricted space (due to snow cover), and similar activity patterns in winter might result in strong competition, causing these species to avoid each other on a spatial scale. The study showed that in addition to species traits and size, ecological settings also play a significant role in deciding the intensity of competition between large carnivores. Climate change and habitat shifts are predicted to increase the spatial overlap between snow leopard and co-predators in the future. In such scenarios, wolves and snow leopards may coexist in a topographically diverse environment, provided sufficient prey are available. However, shifts in tree line might lead to severe competition between common leopards and snow leopards, which could be detrimental to the latter. Further monitoring of resource use across abiotic and biotic environments may improve our understanding of how changing ecological conditions can affect resource partitioning between snow leopards and predators.


Assuntos
Panthera , Lobos , Animais , Humanos , Ecossistema , Comportamento Predatório , Mudança Climática
13.
Polymers (Basel) ; 14(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36080648

RESUMO

The lamellar structure of graphene oxide and the filling effect of nano-cerium oxide particles together provide a good barrier and stability to coating. In this paper, cerium oxide-graphene oxide (4:1) nanocomposite was prepared by the hydrothermal synthesis method. The effect of cerium oxide-graphene oxide (4:1) nanocomposite on the anticorrosion properties of epoxy coating in simulated acid rain solution was studied by open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), Mott-Schottky curve, Tafel curve, and micromorphological characterization, in order to compare it with pure epoxy coating, graphene oxide epoxy coating, and cerium oxide epoxy coating. The obtained results showed that cerium oxide-graphene oxide (4:1) epoxy coating's protection efficiency was as high as 98.62%. These results indicated that cerium oxide-graphene oxide modified anticorrosive coating had an excellent application prospect in an acid rain environment. Meanwhile, owing to the poor protection ability of epoxy resin and unstably hydrolysis product of CeO2 to the acidic medium, the resistance of CeO2-GO (4:1)/EP coating to acidic corrosive medium was relatively poorer than that of neutral and saline-alkali corrosive medium.

14.
Polymers (Basel) ; 14(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35406285

RESUMO

In the marine service environment, metal materials have a serious risk of corrosion. The corrosion rate of metal materials will be accelerated by the dual action of temperature change and alkali salt in saline-alkali environment. In order to delay the metal materials' corrosion rate and prolong their service life, this paper used a CeO2-GO (4:1) nanocomposite prepared by the hydrothermal synthesis method to make an anticorrosion coating. The anticorrosion performance was evaluated by stereo microscope and 3D images of the corrosion site were fitted for calculation. The state evolution of the CeO2-GO (4:1)/EP coating immerged in a simulated saline-alkali solution was studied by open circuit potential (OCP), electrochemical alternating current impedance spectroscopy (EIS), Mott-Schottky curve and Tafel curve. The results indicated that CeO2-GO (4:1) nanocomposites exhibited good resistance compared with graphene oxide and nano cerium oxide in a simulated saline-alkali environment. The research in this paper lays a firm theoretical foundation for the application of nano cerium-oxide-modified graphene oxide anticorrosive coating in saline-alkali environment engineering.

15.
Indian J Pediatr ; 89(9): 865-871, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34767187

RESUMO

OBJECTIVE: To find out the serum fibroblast growth factor 23 (FGF-23) levels in different grades of CKD, and the prevalence of abnormal left ventricular mass index (LVMI), carotid intima-medial thickness (cIMT), and central pulse wave velocity (cPWV) and the risk factors including FGF-23 for these abnormalities. METHODS: Fifty-nine patients of CKD with G2 to G5, aged 2-18 y were included. The LVMI, cIMT, and cPWV were measured using standard techniques, and serum intact FGF-23 levels were estimated at enrollment. RESULTS: Median FGF-23 levels were significantly raised in all the grades of CKD than controls (p < 0.001), and also in G4 and G5 in comparison to G2&3 and in G5D than G5. Increased LVMI in 42 (71.2%), elevated cIMT in 30 (57.7%), and cPWV in 14 (26.9%) patients were found. The FGF-23 showed significant negative correlation with eGFRcr and positive with serum iPTH, phosphate and alkaline phosphatase levels, but had no correlations with LVMI, cIMT SDS, and cPWV SDS. Only systolic BP SDS (odds ratio 1.5, 95% CI 1.008-2.231, p = 0.046) was observed as a significant predictor for increased cIMT, while no variables had any association with abnormal LVMI and cPWV. CONCLUSIONS: Serum FGF-23 showed higher levels with increasing grades of CKD, but no significant association with cardiovascular parameters. Systolic BP SDS was found as a significant risk factor for increased cIMT in children with CKD.


Assuntos
Análise de Onda de Pulso , Insuficiência Renal Crônica , Espessura Intima-Media Carotídea , Criança , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos , Humanos , Insuficiência Renal Crônica/complicações , Fatores de Risco
16.
Nanotechnology ; 33(13)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34874280

RESUMO

To develop high deterioration resistance concrete for marine infrastructures, two types of nano TiO2(NT) including anatase phase NT and silica surface-treated rutile phase NT were incorporated into concrete. The fabricated NT modified concrete was then put into the marine environment for 21 months in this study. The effects and mechanisms of two types of NT on the deterioration of concrete in the marine environment were investigated from three aspects, including seawater physical and biological as well as chemical actions on concrete with NT. Under the seawater physical action, the exposed degree of coarse sand particles on the surface of control concrete is greater than that of concrete with NT. Owing to the microorganism biodegradation property of NT, the elimination and inhibition rates of concrete with NT on microorganisms can reach up to 76.98% and 96.81%, respectively. In addition, the surface biofilm thickness of concrete can be reduced by 49.13% due to the inclusion of NT. In the aspect of seawater chemical action, NT can increase the pH value inside concrete by 0.81, increase the degree of polymerization of C-S-H gel, and improve the interfacial transition zone between cement paste and aggregate in concrete. Compared to anatase phase NT, silica surface-treated rutile phase NT is more effective in improving the deterioration resistance of concrete in the marine environment. It can be concluded that incorporating NT can inhibit the deterioration of concrete in the marine environment.

17.
Popul Health Manag ; 25(1): 57-64, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34264777

RESUMO

There is increasing imperative to train residents in population health. The Accreditation Council for Graduate Medical Education (ACGME) enhanced its mission with revised Common Program Requirements (CPRs), which were fully implemented on July 1, 2020. The revised CPRs state ACGME's mission: "The development of physicians in GME focused on excellence in delivery of safe, equitable, affordable, quality care; and the health of the populations they serve." The new CPRs clearly articulate the need for graduate medical education (GME) trainees to develop and understand population health concepts during their GME experience, including social determinants of health and community impact. However, currently there is no standardized and widely available curriculum for GME to implement these revised CPRs. This paper proposes a curriculum in population health management for GME, which was developed in 1 institution, using a blend of didactic and experiential learning.


Assuntos
Internato e Residência , Médicos , Saúde da População , Currículo , Educação de Pós-Graduação em Medicina , Humanos
18.
Wounds ; 33(7): E53-E57, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34597270

RESUMO

A Marjolin ulcer (MU) is a rare type of skin cancer that most commonly occurs in burns and other traumatic scars, and it also may arise in chronic, poorly healing wounds. Typically, MU presents as a squamous cell carcinoma and has a high rate of metastasis resulting in poor prognosis. The mechanism of the aggressive and metastatic potential of MU has not been clearly defined. This malignancy is more common in patients who are elderly or immunocompromised and has also been characterized as a disease of economically developing nations in which health care resources are less abundant and treatment is delayed. Marjolin ulcer is a challenging, although rare, disease. This article presents a case of MU that arose in a chronic sacral pressure ulcer. This was a rare, multifactorial case; the patient's many comorbidities required coordinated efforts by wound care, oncology, and infectious disease specialists. As seen in this case, MU can be insidious and may not become apparent until considerable progression has occurred. This article discusses the multidisciplinary treatment measures undertaken for this patient, the strategies for prophylaxis and early detection of MU, and ultimately, the poor prognosis of MU in such a scenario where diagnosis is delayed.


Assuntos
Carcinoma de Células Escamosas , Úlcera por Pressão , Neoplasias Cutâneas , Úlcera Cutânea , Idoso , Carcinoma de Células Escamosas/terapia , Detecção Precoce de Câncer , Humanos , Úlcera por Pressão/etiologia , Úlcera Cutânea/etiologia , Úlcera
19.
Polymers (Basel) ; 13(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202424

RESUMO

Graphene is a two-dimensional sheet of regular hexagonal honeycomb lattice formed by sp2 hybrid orbital bonding, with only one layer thickness of a single atom, which is known as the "super king" of the 21st century. Previous studies have shown that cerium oxide-graphene oxide (CeO2-GO(4:1)) nanocomposites eliminated the agglomeration of graphene to some extent and the CeO2-GO(4:1) epoxy coating could be prepared with good anti-corrosion performance. In this paper, CeO2-GO(4:1) nanocomposites were prepared by the hydrothermal synthesis method, and the three-electrode method was used for electrochemical tests. The state evolution of CeO2-GO(4:1)/EP coating and the synergy between CeO2-GO(4:1)/EP and corrosion inhibitor in simulated seawater solution with different concentrations (20%, 40%, 60%) were analyzed and illustrated by Optical Microscope (OM) characterization, Open Circuit Potential (OCP), Electrochemical alternating current Impedance Spectroscopy (EIS), Mott-Schottky curve and Tafel curve. The results indicated that CeO2-GO(4:1) nanocomposites showed good corrosion resistance in a marine environment. This research lays a solid theoretical foundation for the application of cerium oxide-modified graphene oxide anticorrosive coating in marine engineering.

20.
Sci Total Environ ; 750: 141704, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33182205

RESUMO

Serious limitations of the existing water classification schemes prompted us to propose a new statistically coherent water nomenclature system. An extensive database of ionic charge-balanced concentrations of 8 elements (4 cations Ca, Mg, Na, and K; and 4 anions SO4, Cl, HCO3, and CO3), in 46,292 multivariate outlier-free simulated samples, was used for training the multidimensional classification system. The initial assignment for 16 classes was achieved from the greater molar concentration concept of each cation and anion, called the Greater molar conc model. Seven hybrid log-ratios (hlr) from 8 elemental concentrations were used for linear discriminant analysis (LDA) and canonical analysis to propose 16 multidimensional discriminant functions from the 7 hlr model. The LDA and canonical analysis were also performed on the initial molar concentrations of 7 elements, without any log-transformation, which was designated as the 7 M conc model. The robustness of these three classification systems (7 hlr, 7 M conc, and Greater molar conc) was tested against analytical uncertainty propagation and mineral-water interaction effects. The 7 hlr model, due to its higher robustness, was considered as the best option for the nomenclature of the 16 types of water. From the probability concept, it was possible to identify hybrid water types, along with the basic or primary types of water. Our water classification scheme (7 hlr model under the "basic+hybrid" option) can classify as many as 256 different classes of water. Due to the clearly high complexity of the proposed classification scheme, we developed a new online computer program WaterMClaSys_LDA (Water Molar Classification System from Linear Discriminant Analysis) available at our web portal http://tlaloc.ier.unam.mx, for use by anyone after registration and log-in. The usefulness of the new classification scheme is illustrated by applications to groundwater, lake water, and geothermal water samples from South India, Mongolia, and western Turkey, respectively.

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