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• The 2023 ACS update removed the 15-years since smoking cessation requirement for lung cancer screening eligibility. • The updated guideline increases the number of eligible patients for LCS. • Up to 61.8% of our patients were LCS-ineligible due to not meeting the 15-year quitting timeline. • Immediate implementation of updated LCS guidelines is complicated. • Coordinated efforts by advocates and healthcare professionals are needed to improve LCS coverage under new ACS guideline. [ABSTRACT FROM AUTHOR]

Various complications that can occur during and after cranial surgery have been investigated extensively. One of the less frequent complications has thus far received little attention, however: displacement of the skull implant after craniotomy or craniectomy. The purpose of this study is to identify prognostic factors for the development of skull implant displacement (SID). In this study, 9087 cranial surgeries performed between 2002 and 2017 were retrospectively examined for the occurrence of SID. Because a first analysis of the investigated data revealed that a notable number of SIDs occurred after a cranioplasty (CP) performed after a decompressive craniectomy (DC), we focused our investigation on these cases. A total of 669 DCs and 329 subsequently performed CPs were analyzed. Several factors were analyzed unadjusted as possible factors influencing the risk for the development of SID. A total of 13 implant dislocations occurred after CP (3.95%). Fixation technique is the only factor that seems to have had a significant influence, specifically not using miniplates as the fixation technique, which was associated with a higher risk of SID (P = 0.043). However, if fixation techniques are distinguished in more detail, no significant advantage of the miniplates over titanium clamps can be proven (P = 0.123). None of the remaining observed factors showed a statistically provable impact in our data. A notable number of SIDs only occur after CPs that follow a DC. An advantage in successful placement was observed when fixation of the skull implant during cranioplasty was performed using miniplates. [ABSTRACT FROM AUTHOR]

In the present study, the application of graphene-coated polyurethane (PU) sponge for the selective absorption of oil spills from water was carefully investigated. Nanoporous graphene (NPG), prepared by the chemical vapor deposition (CVD) method, and graphene oxide (GO) flakes produced by a modified Hummer’s method, were individually integrated with the porous texture of PU, leading to NPG/PU and GO/PU preparation respectively. The structure and surface properties of the modified sponges were characterized using Fourier Transform Infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), and optical contact angle measuring device. The NPG/PU sponges depict a high capacity to remove crude oil and organic liquid stains. The obtained absorption capacity for NPG/PU sponge was much higher than that of GO/PU sponge, and was recorded at 70 g/g for crude oil removal. In other word, the modified sponges indicated up to 230% increase in the uptake of crude oil. Absorbent recyclability was also evaluated, and after 10 times of reuse, just a negligible decrease in absorption capacity was observed. Consequently, in oil spill absorption, graphene-coated polyurethane (PU) sponge can be considered a relatively more cost-effective method compared to other methods, such as graphene sponges, and can be applied on a large scale. [ABSTRACT FROM AUTHOR]

The palladium-incorporated catalyst, (0.5% Pd/C) (nanospace engineering KOH-activated carbon material) catalyst with macro-structured carbon nanofibers aggregates and micro-nano-porous activated carbons, has been studied as a candidate for hydro-purification of crude terephthalic acid containing of 4- carboxybenzaldehyde (4-CBA) as an impurity. The efficiency of different carbon structures (macro/micro) was investigated over selectivity catalyst. The reaction products were analyzed by HPLC to determine the amounts of 4-CBA, benzoic acid (BA), 4-Hydroxymethyl benzoic acid (4-HMBA) and para-toluic acid (p-tol). It has been confirmed that 0.5% Pd/microporous catalyst gave an excellent performance to catalyze the hydrogenation of 4-CBA to para-toluic acid due to high micro-porous surface area and the most desirable selectivity to 4-HMBA was obtained with macro-structured carbon nanofibers. Pd/AC catalyst with more micro surface area (85.26%) achieved a maximum yield to the intermediate product of 4-HMBA only 30% whereas the macro-structured CNFs achieved typically 66%. The desired selectivity to para-toluic acid was found to be deep dependent on the micro-porous structure. [ABSTRACT FROM AUTHOR]

In this study, to remove CO 2 and H 2 S from a natural gas stream through some absorption experiments, a nanofluid containing SiO 2 and Al 2 O 3 nanoparticles in Diethanolamine was used. We employed a wetted wall column system in a laboratory scale. Some quantities including the nanoparticle dosage, the liquid, and gas flow rates were adjusted to the best removal percent. The range of nanoparticle concentration varied from 0.005 to 0.5 wt. % in our experiments. The nanofluids were prepared by ultrasonic treatment and showed acceptable stability. In addition, a parametric analysis was performed to explore the effects of particle types, as well as concentrations on absorption of H 2 S and CO 2 . The results showed up to 33% improvement of CO 2 absorption at 0.05 wt. % of Al 2 O 3 /DEA nanofluids, and also 40% at 0.05 wt.% of SiO 2 /DEA nanofluids for sample no.1 (feed gas mixture composition: 50 ppm H 2 S and 3% CO 2 in balance of CH 4 ). Moreover, adding silica nanoparticles to DEA deteriorated the absorption of H 2 S; whereas using Al 2 O 3 /DEA nanofluid with 0.1wt.% Al 2 O 3 enhanced the absorption by 14%. [ABSTRACT FROM AUTHOR]

In this research, UiO-66-NH 2 was synthesized with solvothermal method and analyzed by XRD, SEM, BET, TGA and IR spectroscopy to understand its crystalline structure, morphology, thermal stability, and porous structure. Mass fraction of 0.1% of UiO-66-NH 2 added to aqueous solution of mass fraction of 40% N-Methyldiethanolamine (MDEA). Measurement of zeta potential showed that UiO-66-NH 2 particles are stable in aqueous mass fraction of 40% MDEA. The solubility of carbon dioxide investigated in aqueous solution of mass fraction of 40% MDEA and the prepared mixture of mass fraction of 0.1% of UiO-66-NH 2 nanofluid in aqueous solution of mass fraction of 40% MDEA at temperatures of 303.15, 313.15, 323.15, and 333.15 K, and carbon dioxide pressures up to 2300 kPa. Results showed that addition of UiO-66-NH 2 nanoparticles to the MDEA solution, increased capacity of CO 2 absorption of solution up to 10%. The solubility of CO 2 increased with increasing partial pressure and decreased with increasing temperature for both systems. [ABSTRACT FROM AUTHOR]

Nano-composite of multiwall carbon nanotube, decorated with NiFe 2 O 4 nanoparticles (NiFe 2 O 4 –MWCNT), was synthesized using the sol–gel method. NiFe 2 O 4 –MWCNTs were characterized using different methods such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM) and vibrating sample magnetometer (VSM). The average size of the crystallites is 23.93 nm. The values of the saturation magnetization (M S ), coercivity (H C ) and retentivity (M R ) of NiFe 2 O 4 –MWCNTs are obtained as 15 emu g − 1 , 21 Oe and 5 emu g − 1 , respectively. In this research, NiFe 2 O 4 –MWCNT thin films were prepared with the spin-coating method. These thin films were used as the H 2 S gas sensor. The results suggest the possibility of the utilization of NiFe 2 O 4 –MWCNT nano-composite, as the H 2 S detector. The sensor shows appropriate response towards 100 ppm of H 2 S at 300 °C. [ABSTRACT FROM AUTHOR]

In this study, graphene oxide (GO) nanosheets were synthesized by the modified Hummers method. GO structure was estimated by XRD, UV–vis-spectrophotometer and SEM imaging. Then homogeneous and stable GO/water nanofluid was prepared. The effects of GO concentration and temperature on the thermal conductivity were investigated. The measurements of thermal conductivity indicate that the nanofluids have substantially higher thermal conductivities than the base fluid. The thermal conductivity enhancement depends strongly on the concentration of GO and increases with the increasing loading. When the nanosheet loading is 0.25 wt.%, the enhancement ratio is 33.9% at 20 °C and when the temperature increased to 40 °C the enhancement is up to 47.5%. Therefore the level of enhancement is dependent of temperature in the measured temperature range. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the preparation of highly stable nano-porous Ni–Cu catalysts for simultaneous production of CO x –free hydrogen and carbon nano-fibers. The main features of this work focuses on the optimization, methods of catalyst preparation and application of an experimental model for deactivation. The fresh catalysts and the deposited carbon were characterized by SEM, TEM, XRD and Raman spectroscopy. Whatever to be the preparation methods, performance tests showed that the presence of Cu as promoter in Ni–Cu–MgO catalysts, enhanced the catalytic activity, substantially at higher temperatures with the best result obtained for Ni–Cu–MgO catalyst prepared by one step sol- gel method, reaching a hydrogen concentration of 70 vol% (160.51 mol H2/mol Ni-1 h) and a smaller value of ID/IG (less imperfection) for produced carbon nano-fibers at 670 °C. Detailed rate-based model for deactivation of catalyst was found to be dependent on the time, reaction temperature and partial pressure of methane and indicated that the reaction of deactivation could be modeled by a simple hyperbolic model. [Copyright &y& Elsevier]

Abstract: In the present work, effects of different surface modification methods (surfactant, acid, base, amide, sulfate) on multi walled carbon nanotubes (CNTs) are studied. The dispersion stability of CNTs in aqueous media was confirmed and the effects of the type of treatment on the thermal conductivity of CNT/water nanofluids were investigated. The surface of the CNTs was modified with acid mixtures (H2SO4–HNO3), potassium persulfate (KPS), tetrahydrofuran (THF), octadecylamine and sodium dodecyl sulfate (SDS). UV–visible spectral data indicate that the CNTs treated first with the acid mixture and then with KPS show the best dispersion stability. The basic treatment and SDS treated CNT/water nanofluids (SDS-KCNT/water) showed the highest conductivity of 0.765W/mK which increases 24.9% of water as a base fluid conductor. [Copyright &y& Elsevier]

Abstract: In the present study, tin-promoted Pd/MWNTs nanocatalysts were prepared via polyol method for further application in highly concentrated acetylene hydrogenation. Particle sizes decreased drastically with addition of tin, indicating a narrow particle size distribution. The particle sizes and the associated distribution remained constant, even after aging the nanocatalyst upon the reaction for a long time. Addition of tin to Pd catalysts showed good propensity towards the highly-stabilized catalysts, in particular, at the molar ratios of Sn/Pd more than 0.25 up to 1. To characterize the catalysts examined, TEM, XRD, TPR, XPS, SIM DIS, FTIR and TPO were applied. XPS and XRD experiments confirmed the formation of intermetallic compounds and Pd2Sn alloy, respectively. The results showed that the presence of these structures on the catalyst surfaces were responsible for the higher catalytic performance, especially, for the catalysts with higher molar ratios of Sn/Pd. Also, a novel mechanism was proposed based on which the higher values of Sn/Pd were more unaffected in contrast to deactivation. This was attributed to the lower ability of the catalyst to dehydrogenate carbonaceous species, which in turn, decreased the spillovers of carbonaceous species from the catalyst surface to the support, increasing the life time of the catalyst. [Copyright &y& Elsevier]

Abstract: In this research, the performance of nanoscale SiO2 in cement mortars was experimentally studied. The experimental results illustrate that the SiO2 nanostructure, which was mixed with the cement mortars was highly beneficial in improving the rheological properties of drilling cement slurry, concurrently producing an increase in the compressive and flexural strengths of the cement mortar. In addition, there was no free water found in the designed slurries using nanosilica. Results indicated that by using this nanosilica, the setting time and the length of the dormant period were decreased. Also, studying the porosity of cements designed using nanosilica showed a decrease in cement porosity as the amount of nanosilica was increased in the investigated slurries. Moreover, cements designed by using these silica nanostructures had the lowest permeability among all examined ones, which were designed utilizing other methods. [Copyright &y& Elsevier]

Abstract: Heat transfer enhancement of multi-walled carbon natube(MWNT)/water nanofluid in a horizontal shell and tube heat exchanger has been studied experimentally. Carbon nanotubes were synthesized by the use of catalytic chemical vapor deposition (CCVD) method over Co–Mo/MgO nanocatalyst. Obtained MWNTs were purified using a three stage method. COOH functional groups were inserted for making the nanotubes hydrophilic and increasing the stability of the nanofluid. The results indicate that heat transfer enhances in the presence of multi-walled nanotubes in comparison with the base fluid. [Copyright &y& Elsevier]

Abstract: This paper investigates the effect of functional groups on the hydrogen sulfide sensing properties of multi-walled carbon nanotubes using carboxyl and amide groups and Mo and Pt nanoparticles as decorated precursors in gaseous state at working temperature. Carbon nanotubes were synthesized by the CVD process and decorated with the nano particles; provide higher sensitivity for H2S gas detection. The MWCNTs were characterized by scanning electron microscopy combined with energy dispersive X-ray (SEM/EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), ATR-IR absorption and Fourier transforms infrared (FT-IR) analyses. The MWCNTs were deposited as a thin film layer between prefabricated gold electrodes on alumina surfaces. The sensitivity of carbon nanotubes was measured for different H2S gas concentrations and at working temperature. The results showed that the measured electrical conductance of the modified carbon nanotubes with functional groups is modulated by charge transfer with P-type semiconducting characteristics and metal decorated carbon nanotubes exhibit better performances compared to functional groups of carboxyl and amide for H2S gas monitoring at room temperature. [Copyright &y& Elsevier]

Abstract: In this work methane was decomposed to hydrogen and carbon to determine its kinetic behavior during reaction over a Co–Mo–MgO supported catalyst using the CVD (Chemical Vapor Deposition) technique. Decomposition of methane molecules was performed in a continuous fixed bed reactor to obtain data to simulate methane decomposition in a gas phase heterogeneous media. The products and reactants of reaction were analyzed by molecular sieve column followed by GC-analysis of the fractions to determine the amount of product converted or reactant consumed. The synthesis of single-walled carbon nanotubes was performed at atmospheric pressure, different temperatures and reactant concentrations. The experimental data analyzed to suggest the formula for calculation of the initial specific reaction rate of the carbon nanotubes synthesis, were fitted by several mathematical models derived from different mechanisms based on Longmuir-hinshelwood expression. The suggested mechanism according to dissociation adsorption of methane seems to explain the catalytic performance in the range of operating conditions studied. The apparent activation energy for the growth of SWNTs was estimated according to Arrhenius equation. The as grown SWNTs products were characterized by SEM, TEM and Raman spectroscopy after purification. The catalyst deactivation was found to be dependent on the time, reaction temperature and partial pressure of methane and indicated that the reaction of deactivation can be modeled by a simple apparent second order of reaction. [Copyright &y& Elsevier]

In this paper, bandwidth improvement of E-plane sectionalized rectangular horn antenna is studied, which has been introduced for sidelobe level (SLL) reduction and gain improvement of traditional rectangular horn antennas. The main drawback of initial sectionalized horn antenna is the limited bandwidth. In this paper, a reason of this drawback is explained, which is the presence of phase variance of electromagnetic fields on the aperture, and a method is proposed for solving this issue, which is the modification of the phase velocity based on the equations for rectangular waveguides. Consequently, as well as modifying the field amplitudes on the aperture, the proposed method can be used for modification of the phase variance on the aperture. Based on this method, an approximately constant phase on the E-plane of the aperture is obtained. The effectiveness of this method is validated by illustrating the field distributions inside the antenna and on the aperture in simulations. Consequently, bandwidth enhancement by resolve of the initial antenna drawback at the higher frequencies, efficiency improvement without changing the antenna length, and successful measurements for validating the calculations and simulations are the main achievements of this paper. The aperture efficiency of the proposed X-band antenna is higher than 54 % for the frequencies below 11.3 GHz. [ABSTRACT FROM AUTHOR]

The possibility of reducing sidelobe levels (SLLs) of the E-plane radiation patterns of high-gain rectangular horn antennas by modifying the field distribution on the aperture is studied in this paper. A simple and efficient method for controlling the field distribution on the aperture is proposed by sectionalizing the aperture and using conductive plates inside the antenna to obtain the required tapering for SLL reduction. The resulting radiation patterns indicate significant SLL reductions and remarkable gain improvements over a wide bandwidth. Looking from another aspect, the proposed method can be used for SLL reduction and length reduction of high-gain rectangular horn antennas in a wide frequency band. Finally, a prototype of the proposed E-plane sectionalized rectangular horn antenna with 9 sections is fabricated and tested, successfully. The SLL of the proposed antenna compared with traditional horn antennas is reduced from above −15 dB to below −20 dB and the gain is improved by up to 1.8 dB. The measured gain is above 24.5 dB at 10 GHz with 1 GHz bandwidth. [ABSTRACT FROM AUTHOR]

Objective: After an intracerebral hemorrhage, there is an immunological reaction, the specific mechanism of which is not fully understood, that seems to contribute to secondary brain injury. In this study, we investigated alterations of inflammatory markers in the blood and clinical outcome after an intracerebral hemorrhage.Methods: Between July 2013 and February 2016, we performed a prospective study for which we recruited patients who had suffered an intracerebral hemorrhage. Using various scoring scales we evaluated the neurological state upon admission and discharge, and at one and three months following the ICH. During the hospital stay, various inflammatory markers were examined in blood samples.Results: Out of 132 screened patients, 27 were included (48.2% male, mean age 68 years). We found significantly elevated serum concentrations of interleukin-6 (p=0.006) at the time of admission and throughout days three and five. There were also elevated c-reactive protein and granulocyte-colony stimulating factor concentrations found. The concentrations of these immune parameters showed significant monotonic relationships. The ROC analyses showed a better discrimination for mortality with regard to the percentage of T helper cells than with regard to the ICH volume alone.Conclusion: Our results may be regarded as preliminary evidence of the occurrence of inflammation after intracerebral hemorrhage. If there is a relationship between inflammation and clinical outcome remains speculative. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the prevalence of financial hardship and Health-Related Social Needs (HRSN) among patients who missed their radiology appointment. English-speaking adult patients, with a missed outpatient imaging appointment at any of a tertiary care imaging centers between 11/2022 and 05/2023 were eligible. We measured self-reported general financial worry using Comprehensive Score for Financial Toxicity (COST), imaging hardship (worry that the current imaging is a financial hardship to patient and their family), material hardship (e.g., medical debt), cost-related care nonadherence, and HRSNs including housing instability, food insecurity, transportation problems, and utility help needs. 282 patients were included (mean age 54.7 ± 15.0 years; 70.7 % female). Majority were non-Hispanic White (52.4 %), followed by Asian (23.0 %) and Hispanic (16.0 %) racial/ethnic background. Most missed appointments were patient-initiated (74.8 %); 13.5 % due to cost or insurance coverage and 6.4 % due to transportation and parking. Mean COST score was 26.8 with 44.4 % and 28.8 % reporting their illness and imaging as a source of financial hardship. 18.3 % and 35.2 % endorsed cost-related care nonadherence and material hardship. 32.7 % had at least one HRSNs with food insecurity the most common (25.4 %). Only 12.5 % were previously screened for financial hardship or HRSNs. Having comorbidity and living in more disadvantaged neighborhoods was associated with higher report of financial hardship and HRSNs. Financial hardship and HRSNs are common among those who miss radiology appointments. There needs to be more rigorous screening for financial hardship and HRSNs at every health encounter and interventions should be implemented to address these. • In this study of 282 patients, 44.4 % and 32.7 % reported experiencing financial hardship and HRSNs, respectively. • Majority of missed appointments were patient-initiated (74.8 %). • 13.5 % of missed appointments were due to cost or insurance coverage and 6.4 % due to transportation and parking. • Only 12.5 % of participants reported receipt of prior screening for financial hardship or HRSNs. • Implementation of strategies to screen and address such needs at every health encounter is recommended. [ABSTRACT FROM AUTHOR]

Highlights: [•] Production of activated alumina by a less expensive procedure. [•] Preparation of nanostructure activated alumina with high sorption capacity in low and high relative humidity for the first time. [•] Preparation of nanostructure activated alumina with ink-bottle pores (mesopore). [•] Production of the hybrid activated alumina. [Copyright &y& Elsevier]

Abstract: In this study nanofluids from functionalized Graphene were prepared by alkaline method. The nanosheet Graphene was synthesized by using CVD method. For dispersion of Graphene in water, it was hydrophilic by treating with the new alkaline method. Herein, it was reported as a facile and effective approach in preparing water-soluble Graphene by considering the potassium carboxylate (a mild oxidation process using potassium persulfate (KPS). Different parameters of time and temperature effects on thermal conductivity variations of alkaline functionalized Graphene (AFG) at different concentrations have been studied. The best result shows enhancement of thermal conductivity around 14.1% for the sample with 0.05wt.% of AFG compared to water at 25°C and 17% at 50°C. [Copyright &y& Elsevier]

Abstract: In this research, the pristine CNTs sample synthesized by the CCVD method contains catalytic particles and the carbonaceous impurities, and then the special purification procedure was done. By different methods CNT functionalized with various concentration of COOH was prepared. The carboxylated CNTs were analyzed by back titration method for determining the COOH concentrations on the surface of the oxidized CNTs. Thermal conductivity of difference carbon nanotube fluid has been measured under the stable condition by KD2 prob. For the first time, we have compared the effect of difference COOH concentration as important parameter in stability and heat transfer behavior of nanofluid. The results show that increasing the functionalized group causes better stability and higher thermal conductivity if the surface of MWNT does not damage in functionalize process. [Copyright &y& Elsevier]

Abstract: Theoretically convective heat transfer coefficient depends on velocity and temperature profiles. In this work friction factor and convection coefficient are used in order to compare both profiles for nanofluids and base fluids. For this purpose Al2O3/water (due to its present vast experimental study) and carbon nanotube/water (manufactured and examined with our group) are selected. The results show that velocity profile of a nanofluid is similar to the velocity profile of its base fluid. It is proposed that the change of temperature profile for nanofluids compared to the base fluids is the only variable responsible for unpredictable convective heat transfer coefficient of nanofluids using available correlations. [ABSTRACT FROM AUTHOR]

Abstract: In this work thermal conductivity of the suspension is modeled using resistance model approach. This model considers Brownian motion and interfacial layer as well as a new mechanism where proposed by considering nanoparticles as liquid-like particles. The model can be used for estimation of upper and lower limits of nanofluid thermal conductivity, without any adjustable parameter. Thermal conductivity data of CuO nanofluids are obtained experimentally and the results show that the model is consistent to data. This model has been used for determination of various mechanisms'' portions on thermal conductivity of nanofluids. The results are consistent with our knowledge about nanofluids'' thermal conductivity mechanism. [Copyright &y& Elsevier]