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61.
This study aimed to evaluate the effects of carbon nanofibers (CNFs) on the performance of liquid epoxidized natural rubber (LENR)-modified asphalt. The physical, adhesion and rheological properties were determined by several tests such as penetration, elastic recovery, ring and ball softening point, Brookfield rotational viscometer, AFM and dynamic shear rheometer. LENR was used at concentrations of 3, 6, and 9%, while CNFs were used at contents of 0.3, 0.4, and 0.5% by weight of asphalt. Conventional test results showed that the increases in LENR and LENR/CNFs composite contents in binder leads to an increase in the hardness and consistency and a reduction in the temperature susceptibility of base asphalt. Adhesion results revealed that the addition of CNFs significantly increases the adhesion and bonding properties of base and rubberized binders. Rheological properties analysis exhibited that LENR improved the viscoelastic properties and permanent deformation resistance of asphalt at different temperatures and frequencies. On the other hand, it was found that the addition of CNFs significantly improves the stiffness, elasticity, and hardness of LENR-modified binders. The 6% LENR and 0.4% CNFs were found to be the optimum to enhance the physical, adhesion, and rheological properties of asphalt in this study. Thus, it can be stated that the addition of CNFs is promising to improve the performance of rubberized binders for high temperature applications.  相似文献   
62.
Background:Influenza has been shown to exacerbate heart failure (HF). Importantly, no study to date has examined the relationship between HF hospitalizations (HFH) with laboratory confirmed influenza infections. This study evaluated the association between laboratory confirmed influenza infection and HFH in the two largest hospitals in Saskatchewan, Canada.Methods:We used a retrospective self-controlled case series design to evaluate the association between laboratory-confirmed influenza infection and HFH. We compared the incidence ratio for HFH during the influenza risk interval with the control interval. We defined the influenza risk interval as the seven days after a laboratory confirmed influenza result and the control interval as one year before and after the risk interval.Results:We identified 114 HFH that occurred within one year before and after a positive test result for influenza between April 1, 2010, and April 30, 2018. Of these, 28 (28 admissions per week) occurred during the risk interval and 86 (0.853 admissions per week) occurred during the control interval. The incidence ratio of a HFH during the risk interval as compared with the control interval was 33.53 (95% confidence interval [CI], 21.89 to 51.36). A decline in incidence was observed after day seven; between days 8 to 14 and 14 to 28 incidence ratios was 0.91 (95% CI, 0.13 to 6.52) and 0.91 (95% CI, 0.22 to 3.68) respectively.Conclusion:We have observed a significant association between acute influenza infection and HFH. However, further research with a larger sample size and involving a multicenter setting is warranted.Highlights
  • Influenza may contribute and exacerbate heart failure events especially during annual influenza season.
  • Early identification of influenza among patients with heart failure, could lead to earlier treatment with antiviral medication, reduce unnecessary antibiotic use, and tail off the morbidity and mortality.
  • In this study, despite our efficient study design, our sample size was limited to only the two largest hospitals in the province, possibly excluding a significant population in remote areas.
  相似文献   
63.
Rational modification of molecular structure by incorporating electron donating groups can play a potential role for designing aggregation induced emission (AIE) active fluorescent probes. Based on this principle, fluorescent probes (1a–c) were synthesized, and they displayed excellent aggregation induced emission (AIE) behavior in a H2O/DMF (4 : 1, v/v) mixture due to restrictions in intramolecular charge transfer (ICT). As a comparison, probe 1d was synthesized by installing an electron withdrawing (–NO2) group that surprisingly quenched the aggregation behaviour. Additionally, AIE active probes 1a–c displayed a highly sensitive dual channel (fluorometric and colorimetric) response towards rapid detection of CN, which is an active toxic material. Probes 1a–c showed selectively enhanced fluorescence emission behavior towards CN with detection limits of 1.34 ppb, 1.38 ppb, and 1.54 ppb, respectively. The sensing mechanism involves Michael type adduct formation due to the nucleophilic addition reaction of cyanide with probes and was confirmed through 1H NMR titration experiments. In contrast, probe 1d containing an electron withdrawing moiety showed insensitivity towards CN. Therefore, this study provides the efficient strategy to induce AIE character in fluorescent probes and expands the mechanistic approach toward the sensing of toxic CN.

Rational modification of molecular structure by incorporating electron donating groups can play a potential role for designing aggregation induced emission (AIE) active fluorescent probes.  相似文献   
64.
BackgroundStunting occurs due to chronic malnutrition and is a major problem for children in developing countries. It is important to evaluate the impact of stunting on the development of children. This study aimed to investigate the impact of stunting on the development of children between 1–3 years of age.MethodsThis cross-sectional study was conducted from July 2020 to March 2021 in Surabaya, Indonesia. A questionnaire and growth assessment were done, following the development measurement to stunted and non-stunted children who met the inclusion and exclusion criteria. Development was measured by the Denver Developmental Screening Test II (DDST-II), and Cognitive Adaptive Test/Clinical Linguistic & Auditory Milestone (CAT/CLAMS) scales.ResultsThree hundred children are included in this study, consisting of 150 stunted and 150 non-stunted children. Stunted children had a higher risk to be suspected of delayed development compared to non-stunted children. The Crude Odd Ratio was 2.98, 4.24, 4.75 with the p-value 0.006, 0.001. and 0.001 respectively. The Adjusted Odd Ratio was 0.34, 0.24, 0.21 with p-value of 0.008, 0.001, and 0.001 respectively.ConclusionStunting is associated with suspected development delay among children 1–3 years of age. Initiatives related to prevention need to be established and nutrition advice needs to be provided.  相似文献   
65.
66.
A prophylactic hepatitis C virus (HCV) vaccine that elicits neutralizing antibodies could be key to HCV eradication. However, the genetic and antigenic properties of HCV envelope (E1E2) proteins capable of inducing anti-HCV broadly neutralizing antibodies (bNAbs) in humans have not been defined. Here, we investigated the development of bNAbs in longitudinal plasma of HCV-infected persons with persistent infection or spontaneous clearance of multiple reinfections. By measuring plasma antibody neutralization of a heterologous virus panel, we found that the breadth and potency of the antibody response increased upon exposure to multiple genetically distinct infections and with longer duration of viremia. Greater genetic divergence between infecting strains was not associated with enhanced neutralizing breadth. Rather, repeated exposure to antigenically related, antibody-sensitive E1E2s was associated with potent bNAb induction. These data reveal that a prime-boost vaccine strategy with genetically distinct, antibody-sensitive viruses is a promising approach to inducing potent bNAbs in humans.  相似文献   
67.
68.
Graphene is a 2D material with remarkable properties. The present study demonstrates the fabrication of a graphene-based sensor for measuring the temperature and humidity of a metal body. The graphene sensor was fabricated by depositing a thin film of graphene nanoparticles between silver electrodes (separated by ∼50 μm) on a glass substrate. The graphene thin film was characterized by XRD, Raman spectroscopy and UV-vis techniques. The capacitance and resistance for both the relative humidity (in the range of 0–100% RH) and temperature (in the range of 230–310 K) were measured using an LCR meter at 1 kHz in a controlled chamber. The graphene-based sensor expressed high sensitivity with fast response and recovery times for both humidity and temperature with long stability and low hysteresis curves. The sensor was also tested on a metal body, which expressed a good response time. Moreover, the measured data of capacitance and resistance was analyzed with classical and neutrosophic analysis as an application of modern material statistics. It was observed that neutrosophic analysis is more flexible for analyzing the capacitance and resistance of the fabricated sensor.

Graphene is a 2D material with remarkable properties.  相似文献   
69.
PURPOSE: To establish a baseline of phase differences between tissues in a number of regions of the human brain as a means of detecting iron abnormalities using magnetic resonance imaging (MRI). MATERIALS AND METHODS: A fully flow-compensated, three-dimensional (3D), high-resolution, gradient-echo (GRE) susceptibility-weighted imaging (SWI) sequence was used to collect magnitude and phase data at 1.5 T. The phase images were high-pass-filtered and processed region by region with hand-drawn areas. The regions evaluated included the motor cortex (MC), putamen (PUT), globus pallidus (GP), caudate nucleus (CN), substantia nigra (SN), and red nucleus (RN). A total of 75 subjects, ranging in age from 55 to 89 years, were analyzed. RESULTS: The phase was found to have a Gaussian-like distribution with a standard deviation (SD) of 0.046 radians on a pixel-by-pixel basis. Most regions of interest (ROIs) contained at least 100 pixels, giving a standard error of the mean (SEM) of 0.0046 radians or less. In the MC, phase differences were found to be roughly 0.273 radians between CSF and gray matter (GM), and 0.083 radians between CSF and white matter (WM). The difference between CSF and the GP was 0.201 radians, and between CSF and the CN (head) it was 0.213 radians. For CSF and the PUT (the lower outer part) the difference was 0.449 radians, and between CSF and the RN (third slice vascularized region) it was 0.353 radians. Finally, the phase difference between CSF and SN was 0.345 radians. CONCLUSION: The Gaussian-like distributions in phase make it possible to predict deviations from normal phase behavior for tissues in the brain. Using phase as an iron marker may be useful for studying absorption of iron in diseases such as Parkinson's, Huntington's, neurodegeneration with brain iron accumulation (NBIA), Alzheimer's, and multiple sclerosis (MS), and other iron-related diseases. The phases quoted here will serve as a baseline for future studies that look for changes in iron content.  相似文献   
70.
The selection of a facile, eco-friendly, and effective methodology is the need of the hour for efficient curing of the COVID-19 virus in air, water, and many food products. Recently, semiconductor-based photocatalytic methodologies have provided promising, green, and sustainable approaches to battle against viral activation via the oxidative capabilities of various photocatalysts with excellent performance under moderate conditions and negligible by-products generation as well. Considering this, recent advances in photocatalysis for combating the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are inclusively highlighted. Starting from the origin to the introduction of the coronavirus, the significant potential of photocatalysis against viral prevention and -disinfection is discussed thoroughly. Various photocatalytic material-based systems including metal-oxides, metal-free and advanced 2D materials (MXenes, MOFs and COFs) are systematically examined to understand the mechanistic insights of virus-disinfection in the human body to fight against COVID-19 disease. Also, a roadmap toward sustainable solutions for ongoing COVID-19 contagion is also presented. Finally, the challenges in this field and future perspectives are comprehensively discussed involving the bottlenecks of current photocatalytic systems along with potential recommendations to deal with upcoming pandemic situations in the future.

Photocatalysts are green, eco-friendly, clean and sustainable and could be a solution to combat COVID-19 because of potential features of various types of metal oxides against viral inactivation via the generation of reactive oxidative species.  相似文献   
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