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This study examines the performance, combustion, and emissions characteristics of a single-cylinder internal combustion diesel engine when fueled with a blend of diesel and biodiesel derived from muskmelon seeds. The kinematic viscosity of the extracted muskmelon seed oil was 6.1 cSt at 40 °C, which is higher than the kinematic viscosity of petroleum diesel of 2.6 cSt. Muskmelon biodiesel was further analyzed using thin-layer chromatography (TLC) and high-voltage separator tests. A comparison of the fuel properties of muskmelon biodiesel with conventional diesel fuel revealed that muskmelon biodiesel could be used alone or in a diesel–biodiesel blend to fuel compression diesel engines. In this study, muskmelon seed biodiesel was blended with diesel fuel at proportions of 10 %, 20 %, and 50 % (BD10, BD20, and BD50, respectively). At a relatively low rotational speed of 1200 rpm, the brake thermal efficiency (BTE) of the engine operated with BD10 and BD20 blends were 36.1 % and 36.0 %, respectively, while the brake-specific fuel consumption (BSFC) of the two blends were 0.260 kg/kWh, and 0.262 kg/kWh, respectively. These values closely resemble those typically observed in diesel fuel engines. Indeed, the average BTE of the BD20 blend was only 3.24 % less than the average BTE of diesel fuel. Diesel fuel generates less NOx and SO2 emissions compared to biodiesel blends: BD100 emitted the most NOx pollution of all fuels tested. In addition, BD10 released significantly more SO2 emissions compared to the other fuels tested. However, the BD20 blend outperformed all other blends in terms of CO, NOx, and SO2 emissions at high engine speeds. The only exception was H2S emissions, which were higher than BD50 and BD100. BD20 also exhibited significantly reduced CO emissions compared to diesel fuel, while BD10 emitted significantly more CO emissions than the other biodiesel blends. Our findings revealed that BD20 exhibited the best engine performance and lower emissions among all fuels tested. In other words, BD20 is the ideal fuel blend for use in diesel engines and does not require any alterations to the engine. Muskmelon waste seeds represent a non-edible waste stream that can be exploited in the production of biodiesel fuel, allowing for the upcycling of a potentially problematic thermochemical conversion feedstock. This potentially valuable use for waste muskmelon seeds in the energy sector could address the wastefulness associated with this particular waste stream.

Internal audit is a bulwark ensuring the integrity of financial statements, a linchpin for stakeholder trust and informed corporate decision-making. With the proliferation of complex financial transactions, audit teams face mounting challenges in deciphering voluminous transactional data to safeguard financial reporting quality. Machine learning has the potential to identify signifiers of financial reporting quality. Within the Design Science Methodology framework, we apply the Random Forest Classifier technique to metrics such as the error rate to enhance financial reporting. We find that the Random Forest Classifier identifies that certain parameters are critical to error detection, which enhance account receivable accuracy, lower receivable account control risk. This research advances the argument that technologically-enhanced internal audit procedures can play a pivotal role in ensuring that financial reporting mirrors the economic reality of the company.

Abstract Background Pre-exposing plants to abiotic stresses can induce stress memory, which is crucial for adapting to subsequent stress exposure. Although numerous genes involved in salt stress response have been identified, the understanding of memory responses to salt stress remains limited. Results In this study, we conducted physiological and transcriptional assays on maize plants subjected to recurrent salt stress to characterize salt stress memory. During the second exposure to salt stress, the plants exhibited enhanced salt resistance, as evidenced by increased proline content and higher POD and SOD activity, along with decreased MDA content, indicative of physiological memory behavior. Transcriptional analysis revealed fewer differentially expressed genes and variations in response processes during the second exposure compared to the first, indicative of transcriptional memory behavior. A total of 2,213 salt stress memory genes (SMGs) were identified and categorized into four response patterns. The most prominent group of SMGs consisted of genes with elevated expression during the first exposure to salt stress but reduced expression after recurrent exposure to salt stress, or vice versa ([+ / −] or [− / +]), indicating that a revised response is a crucial process in plant stress memory. Furthermore, nine transcription factors (TFs) (WRKY40, WRKY46, WRKY53, WRKY18, WRKY33, WRKY70, MYB15, KNAT7, and WRKY54) were identified as crucial factors related to salt stress memory. These TFs regulate over 53% of SMGs, underscoring their potential significance in salt stress memory. Conclusions Our study demonstrates that maize can develop salt stress memory, and the genes identified here will aid in the genetic improvement of maize and other crops.

Nadia Muhaidat,1 Abdulrahman M Karam,2 Mohammed Saad Nabhan,1 Tala Dabbah,2 Bilal Odeh,2 Mira Eid,2 Nadia Jamal Almahallawi,3 Mohammad Ali Alshrouf2 1Department of Obstetrics & Gynaecology, School of Medicine, The University of Jordan, Amman, 11942, Jordan; 2The School of Medicine, The University of Jordan, Amman, 11942, Jordan; 3Department of Family Medicine, School of Medicine, The University of Jordan, Amman, 11942, JordanCorrespondence: Nadia Muhaidat, Department of Obstetrics & Gynaecology, School of Medicine, The University of Jordan, Amman, 11942, Jordan, Tel +962798385775, Email Nadiadat@hotmail.comBackground: The outcome of embryo transfer (ET) is multifactorial. A variety of patient-related, procedural-related, and operator-related factors are known to play a role. This study aims to evaluate the outcomes of ET and determine the factors that affect the outcome.Methods: The study involved a retrospective design involving 300 first in vitro fertilization and embryo transfer (IVF-ET) cycles between 2011 and 2021. The outcome included 155 unsuccessful cycles and 145 successful IVF-ET leading to pregnancy. The outcomes were examined for different variables, including age, weight, height, body mass index, cause of infertility, number of embryos fertilized during the cycle, day of ET, whether the embryo was frozen, presence of blood or mucus during the procedure, the use of a stylet, tenaculum, uterine sound/dilator, and catheter type. Logistic regression was used to analyze factors affecting the outcomes of ET.Results: The mean age was 27.84 ± 3.77 years. Patients who had blood during the procedure (32.9% vs 17.2%, p = 0.002), mucus (31% vs 20.7%, p = 0.049), or used the tenaculum (16.8% vs 6.9%, p = 0.012) were more likely to have unsuccessful IVF-ET. Logistic regression to adjust for related factors revealed that the presence of blood (AOR = 2.21, 95% CI 1.04 to 4.66, p = 0.038) during the ET had a higher likelihood of an unsuccessful outcome.Conclusion: This study showed that the presence of blood during the ET cycle influenced clinical pregnancy. This highlights the importance of performing the procedure under atraumatic conditions.Level of Evidence: Level III; retrospective comparative study.Plain Language Summary: Infertility is considered an important public health problem in terms of high expenses, treatment complications, and failure. Addressing the factors that impact embryo transfer outcomes may help in guiding counseling and management. Therefore, the aim of this study was to evaluate the results of IVF-ET and assess several patient-related and procedural-related factors that impact those results. It included retrospectively 300 cycles from 2011 to 2021. The presence of blood after embryo transfer was shown to be the major predictor of an unsuccessful cycle. Moreover, although the usage of additional instruments was not significantly associated with a higher risk of failed embryo transfer cycles, the operators should use these instruments with caution in order to avoid any trauma that might result in bleeding.Keywords: IVF, assisted reproductive technique, infertility, pregnancy, predictive factors

Abstract In this review, the radiolytic and physical methods that can be used for the functionalization of carbon nanotubes (CNTs) and their applications as a support for fuel cell electrodes are described. Alloy nanoparticles have also been examined. For example, Pt–Ru nanoparticles were deposited onto a functionalized multiwalled carbon nanotube (MWNT) composite by reducing metal ions (e.g., Pt4+ and Ru3+) here using γ-irradiation and, hence, creating Pt–Ru/MWNT catalysts. The morphology, size, and composition of these Pt–Ru/MWNT catalysts were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and elemental analysis, respectively. The efficiency of the Pt–Ru/MWNT catalyst was examined for use in the oxidation of carbon monoxide (CO) and methanol. The results of stripping voltammetry for the adsorbed CO on the Pt–Ru/MWNT catalyst electrodes indicated that CO oxidation was energetically favorable at these electrodes. Thus, Pt–Ru/MWNT catalysts were found to be suitable for electrode assembly in direct methanol fuel cells.

Ahmed Hussein,1 Mohamed Eid,1 Sharaf E D Mahmoud,1 Mohamed Sabry,2 Ali Altaher1 1Cardiology Unit, Department of Internal Medicine, Faculty of Medicine, Sohag University Egypt, Sohag, Egypt; 2Department of OB/GYN, Faculty of Medicine, Sohag University Egypt, Sohag, EgyptCorrespondence: Ahmed Hussein, Cardiology Unit, Department of Internal Medicine, Faculty of Medicine, Sohag University, Nasser City, Sohag, 82524, Egypt, Tel +2 01011145537, Fax +2 0934600349, Email ahmed_hussien@med.sohag.edu.egBackground: Percutaneous balloon mitral valvuloplasty (PBMV) is considered the most suitable option for managing symptomatic severe mitral valve stenosis (MS) during pregnancy with favorable anatomy. We do not know the best time to perform PBMV during pregnancy to achieve the best maternal and fetal outcomes. Therefore, we conducted this study to clarify the best procedure timing.Methods: This prospective, observational, single-center study involved 44 pregnant patients suffering from symptomatic MS who underwent PBMV from May 2017 to May 2020. A detailed history is taken, full clinical examination, laboratory assessment, 2 D echocardiography, and follow-up during the hospital stay and monthly until labor.Results: We found that the mean mitral valve area (MVA) had significantly increased from 1.12 ± 0.24 to 2.09 ± 0.46 cm2 (P < 0.001). The mean pressure gradient across the mitral valve reduced from 17.22 ± 5.55 to 8.94 ± 3.75 mmHg (P < 0.001). The procedures were successful in 91% of the patients. Regarding obstetric outcomes, the incidence of preterm labor, fetal death, and composite adverse outcomes was significantly lower in patients who had the procedure during the second trimester than those who had the procedure during the third trimester. All preterm deliveries and intrauterine fetal deaths occurred at least 21 days after PBMV. The patients showed a statistically significant improvement in NYHA functional classification.Conclusion: We can conclude that PBMV performed in pregnant patients is an effective and safe treatment modality, and we observed better obstetric outcomes achieved with early intervention during the second trimester.Keywords: rheumatic heart disease, mitral stenosis, PBMV, pregnancy, obstetric outcomes

Due to high filler loading, clean, commercial, thermoplastic, flame-retardant materials are mechanically unstable when insulating wires and cables. In this study, composite formulations of linear low-density polyethylene (LLDPE)/ethylene–vinyl acetate (EVA) containing a flame retardant, such as magnesium hydroxide (MH; formula: Mg(OH)2) and huntite hydromagnesite (HH; formula: Mg3Ca(CO3)4, Mg5(CO3)4(OH)2·3H2O), were prepared. The influence of carbon nanotubes (CNTs) and carbon black (CB) on the mechanical properties and flame retardancy of LLDPE/EVA was studied. Three types of CNTs were examined for their compatibility with other materials in clean thermoplastic flame-retardant compositions. The CNTs had the following diameters: 10–15 nm, 40–60 nm, and 60–80 nm. Optimum mechanical flame retardancy and electrical properties were achieved by adding CNTs with an outer diameter of 40–60 nm and a length of fewer than 20 nm. Large-sized CNTs result in poor mechanical characteristics, while smaller-sized CNTs improve the mechanical properties of the composites. CB enhances flame retardancy but deteriorates mechanical properties, particularly elongation at break, in clean, black, thermoplastic, flame-retardant compositions. Obtaining satisfactory compositions that meet both properties, especially formulations passing the V-0 of the UL 94 test with a minimum tensile strength of 9.5 MPa and an elongation at break of 125%, is challenging. When LLDPE was partially substituted with EVA, the limiting oxygen index (LOI) increased. The amount of filler in the formulations determined how it affected flammability. This study also included a reliable method for producing clean, black, thermoplastic, flame-retardant insulating material for wire and cable without sacrificing mechanical properties.

Mohamed Eid,1 Amr Mounir,2 Shehab El Etriby,3 Ali Al Taher,1 Mohamed AW Ezzat1 1Department of Internal Medicine, Sohag University Hospital, Sohag University, Sohag, Egypt; 2Department of Ophthalmology, Sohag Faculty of Medicine, Sohag University, Sohag, Egypt; 3Department of Cardiology, Ain Shams Faculty of Medicine, Ain Shams University, Cairo, EgyptCorrespondence: Amr Mounir, Email dramrmonir@yahoo.comBackground: Diabetic retinopathy (DR) is one of the most prevalent consequences of diabetes mellitus (DM). Much emphasis has been focused on the link between DR and cardiovascular disorders in patients with type 2 diabetes (T2DM). However, there is little information about the relation between the degree of DR and coronary atherosclerosis severity in Egyptian patients.Aim: To assess the correlation between the degree of DR and the coronary atherosclerosis severity in T2DM.Patients and Methods: This work included 140 diabetic patients with T2DM who underwent diagnostic coronary angiography because of suspected coronary artery disease (CAD). All participants were evaluated by history, fundus assessment, laboratory tests (lipid profile and glycated hemoglobin [HbA1c]), and selective coronary angiography. The severity of coronary artery lesion was detected by Gensini score and vessel score.Results: Patients with DR had a significantly higher Gensini score (67.86± 44.56 versus 5.93± 9.02, P < 0.001) and a vessel score (2.29± 0.86 versus 0.50± 0.66, P < 0.001). There was a significant relation between the degree of DR, Gensini score (P < 0.001), and vessel score (P < 0.001), as both scores increased according to the severity of DR. The presence and degree of retinopathy were the only independent factors linked to the severity score in multivariate linear regression analyses (P < 0.001).Conclusion: The presence and degree of DR are independent predictors of severe coronary atherosclerosis. Therefore, when evaluating whether a patient with T2DM is at high risk for CAD, the DR degree should be taken into consideration.Keywords: diabetic retinopathy, coronary atherosclerosis, type 2 diabetes mellitus, coronary angiography

Zizi M Ibrahim,1,2 Olfat Ibrahim Ali,3 Samah A Moawd,4,5 Marwa M Eid,2,6 Mona Mohamed Taha1,5 1Rehabilitation Sciences Department, College of Health and Rehabilitation Sciences, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia; 2Department of Physical Therapy for Surgery, Faculty of Physical Therapy, Cairo University, Cairo, Egypt; 3Department of Basic Science for Physical Therapy, Faculty of Physical Therapy, Cairo University, Cairo, Egypt; 4Department of Physical Therapy and Health Rehabilitation, College of Applied Medical Sciences, Prince Sattam bin Abdulaziz University, Al-Kharj, Saudi Arabi; 5Department of Cardiovascular/Respiratory Disorder and Geriatrics, Faculty of Physical Therapy, Cairo University, Cairo, Egypt; 6Department of Physical Therapy, Faculty of Applied Medical Science, Taif University, Taif, Saudi ArabiaCorrespondence: Zizi M Ibrahim Email Zizikahla@yahoo.comPurpose: Burn injury with pre-existing diabetes has poorer outcomes and complications. Balance and functional mobility are disturbed in diabetic patients with burn injury which increase the risk of total morbidity. The aim of the current study was to evaluate the impact of vibrational training as an additional intervention on postural balance, balance confidence and functional mobility in type 2 diabetic patients with lower limb burn injury.Patients and Methods: Thirty-eight type 2 diabetic patients of both sexes with healed lower limb burn were randomly assigned into two equal groups: the vibration group and the control group. The vibration group received whole body vibration (WBV), 3 sessions a week for 8 weeks, in addition to the selected exercise program (balance exercises and resisted exercises), while the control group only received the selected exercise program. Biodex Balance System was used to assess the dynamic balance score, the Activities-specific Balance Scale to assess balance confidence and the timed up and go test to assess the functional mobility. All measurements were obtained before and at the end of the study after 8 weeks of treatment.Results: Marked improvement in all dynamic balance indices; overall stability index, antero-posterior stability index and medio-lateral stability index, balance confidence and the functional mobility were obtained in both the vibration and the control groups (P< 0.05), whereas post-treatment comparison between groups revealed a statistically significant difference in favor of the vibration group in all measured variables.Conclusion: Based on the results of the current study, it is possible to conclude that adding WBV training for an 8-week duration to a selected exercise program (balancing and resisted exercises) seems to be effective; in improving postural balance, balance confidence, as well as improving the functional mobility in type 2 diabetic patients with lower limb burn injury.Keywords: burn injury, postural balance, vibrational training, functional mobility, resisted exercises

Nickel ions are hazardous heavy metals that are non-biodegradable and can lead to allergic sensitivity and dermatitis. Nanomaterials are chosen for their effective elimination of impurities from water structures based entirely on the variety of therapy and degree of purification. The target of this work was the combination of the properties of biopolymers such as chitosan, silver nanoparticles (SNPs), and carbon nanotubes (CNTs) in one ecofriendly compound for Ni (II) uptake from the aqueous solution. To attain this target, the endeavor was made by creating a nanocomposite based on chitosan/SNPs/CNTs. The characterization of the structure of the fabricated nanocomposite (Chit-SNPs-CNTs) was carried out using different techniques. The removal of Ni (II) was examined by studying the adsorption of Ni (II) ions onto the fabricated nanocomposite by batch adsorption using UV, XRD, XPS, and ICP techniques. Moreover, we investigated the effect of the contact time, pH of the solution, and mass of the adsorbent on the efficiency of the adsorption of Ni (II). The results show that the adsorption capacity of Ni (II) increased by increasing the contact time with a neutral pH. The maximum removal of Ni (II) ions (99.70%) was found using 0.3 g of the (Chit-SNPs-CNTs) nanocomposite. In addition, the results indicate that the fabricated nanocomposite has a high adsorption effectivity, which is associated to the function of the chitosan, SNPs, and CNTs in upgrading the adsorption efficiency. Finally, the results in the existing work indicate that the ecofriendly nanocomposite organized here gave excessive effectivity closer to the elimination of Ni (II).

Electrophotographic printing and copying processes primarily use toner, which is a mixture of colorant, polymer, and additives. Toner can be made using traditional mechanical milling techniques or more contemporary chemical polymerization techniques. Suspension polymerization provides spherical particles with less stabilizer adsorption, homogeneous monomers, higher purity, and easier control of the reaction temperature. In contrast to these advantages, however, the particle size resulting from suspension polymerization is too large for toner. To overcome this disadvantage, devices such as high-speed stirrers and homogenizers can be used to reduce the size of the droplets. This research investigated the use of carbon nanotubes (CNTs) instead of carbon black as the pigment in toner development. We succeeded in achieving a good dispersion of four different types of CNT, specifically modified with NH2 and Boron or unmodified with long or short chains in water rather than chloroform, using sodium n-dodecyl sulfate as a stabilizer. We then performed polymerization of the monomers styrene and butyl acrylate in the presence of the different CNT types and found that the best monomer conversion and largest particles (in the micron range) occurred with CNTs modified with boron. The insertion of a charge control agent into the polymerized particles was achieved. Monomer conversion of over 90% was realized with all concentrations of MEP-51, whereas conversion was under 70% with all concentrations of MEC-88. Furthermore, analysis with dynamic light scattering and scanning electron microscopy (SEM) indicated that all polymerized particles were in the micron size range, suggesting that our newly developed toner particles were less harmful and environmentally friendly products than those typically and commercially available. The SEM micrographs clearly showed good dispersion and attachment of the CNTs on the polymerized particles (no CNT aggregation was found), which has never been published before.

Abstract Background The chemical composition of Handal (Citrullus colocynthis L.) seed oil cultivated in Jordan deserts was characterized, and its bioactivity was evaluated. Methods The oil was extracted from the grinded seeds in 500 ml Soxhlet extractor for 24 hr using n‐hexane, and the recovered fatty acids were methylated with methanolic‐HCL. The fatty acid methyl esters (FAMEs) composition was analyzed using GC‐MS and GC‐FID. The anticancer activity associated with the oil was assessed against colon cancer cell lines (Caco‐2 and HCT‐116) and compared to its cytotoxicity on the human skin fibroblast. Multivariate analysis was used to determine relationship of the fatty acid composition with that of the anticancer activity. Results The results demonstrated that fatty acid composition of Citrullus colocynthis seed oil chiefly contains Linoleic acid, denoted as C18:2n6 (75%), followed by Palmitic acid C16:0 (8%), Stearic acid C18:0 (5%), and Oleic acid C18:1n9 (9%). It is demonstrated as an excellent source of essential fatty acids omega‐6 (e.g., Linoleic acid), whereas omega‐3 (e.g., α‐Linolenic acid) and hydroxy polyunsaturated fatty acids are found at small level. Interestingly, the oil exhibited reasonable anticancer effects against colorectal cancer cell lines with IC50 values varying between 4 and 7 mg/ml. The correlation test revealed a relationship between the fatty acid composition and the effectiveness on treatments. Conclusions Handal plant from Jordan appears to have very high level of Linoleic acid compared to other oils measured in different geographic locations and that there appears to be some anticancer activities associated with the fatty acid content of Handal seed oil.

Because of their high filler loadings, commercial-grade clean flame-retardant materials have unstable mechanical properties. To address this issue, intumescent polymers can be used to develop clean flame retardants with very low levels of smoke and toxicity generation. An intumescent flame retardant (IFR) system composed of red phosphorus (RP), zinc borate (ZB), and a terpolymer of ethylene, butyl acrylate, and maleic anhydride (EBM) was used to prepare EVA (ethylene-vinyl acetate) and EVA/LLDPE (linear low-density polyethylene) composites; their mechanical and flammability properties were systematically investigated. The limiting oxygen index (LOI) of the EVA/LLDPE (as base material) composite containing RP and ZB mixed with nonhalogenated flame retardant, mainly magnesium hydroxide (MH) and coadditives, including processing aids and thermal stabilizers, was established. RP was found to have little effect on the tensile properties of EVA/LLDPE 118W/120 phr flame-retardant (MH + RP) composites. There was a minute difference in the effective trend of RP between tensile strength and elongation at break. Following the addition of ZB, the elongation at break of the composites gradually decreased with increasing RP content and then leveled off when the RP content was over 10 phr. Mechanical properties (elongation at break and tensile strength) can be best maintained at below 10 phr content of RP. The mechanical properties decreased with lower amounts of EBM content. In addition, flame retardancy increased when the EBM content decreased. The findings further revealed that MH and RP have poor compatibility, yielding poor mechanical properties. The LOI greatly increased with RP content, even though the total content of flame retardants (main + intumescent flame retardant) was the same in all formulations. Only over 5 phr RP content formulations passed V-0 of the UL-94 test. When under 5 phr, the RP content formulations did not pass V-0 of the UL-94 test.

The oxidation of chlorobenzene (CB) was studied by electrochemical electrolysis using boron-doped diamond (BDD), PbO2 or platine (Pt) as anode and graphite bar as cathode. The effect of applied current density, supporting electrolyte and initial pH value were also studied. The results demonstrated that BDD anode had the best effectiveness and accomplishment of electrochemical degradation of CB compared to PbO2 and Pt anodes. For a current density of 20 mA/cm2 and at pH = 3, the elimination of COD and TOC were about 97% and 98%, respectively, after 360 min of electrolysis with the BDD anode. Pseudo-first order kinetics appears to be the most appropriate to describe the degradation of chlorobenzene. The electrochemical mechanism of chlorobenzene on BDD was proposed based on the identified intermediates.

Poly (ethylene-co-vinyl acetate) (PEVAc) is a copolymer endowed with high elasticity and resilient properties, potentially utilized in various applications. However, the tensile strength of this copolymer is insufficient for use in certain applications that require enough strength to tolerate high external tension or stress. In this study, dolomite was proposed as a nanofiller to reinforce the PEVAc. Raw dolomite was physically and chemically modified in order to improve its mix ability and interfacial adhesion between the PEVAc and dolomite. Initially, the size of dolomite was reduced by combining the ball-milling and tip-sonication methods. SEM, TEM, and XRD were used to characterize the morphology/structure of the raw dolomite and the size-reduced dolomite. Then, a particle size analysis was performed to confirm the average particle size. Our results show that the particle size of dolomite was reduced from 150 µm to 441.4 nm by the physical modification process (size reduction). Based on the TEM analysis, the Feret diameter (df) of the dolomite particles was also reduced from ~112.78 µm to ~139.58 nm only. This physically modified dolomite is referred as dolomite nanoparticles (DNPs), since one or more of its dimensions is less than 100 nm (e.g., thickness and width). To further improve the dolomite and PEVAc matrix interactions, chemical modification of the DNPs were performed by treating the DNPs with stearic acid, forming non-polar dolomite nanoparticles (NP-DNPs). The presence of stearic acid in dolomite was confirmed through FTIR and contact angle analyses. A PEVAc nanocomposite film with NP-NPDs as a nanofiller appeared more homogeneous and exhibited the highest increment in tensile strength and elongation at break. These findings indicated that the combination of ball milling and tip sonication is an efficient method for producing very fine dolomite particles up to the nano-size range, whereas chemical surface modifications improved the compatibility between the dolomite and the copolymer. The combination of these physical and chemical modifications helped to develop a homogeneous copolymer nanocomposite system with improved tensile properties.

This work proposes and statistically analyzes a hexagonal-shaped hollow-core photonic crystal fiber-based edible oil sensor in the terahertz (THz) range. The suggested sensor’s performance was assessed by means of Comsol Multiphysics, a finite element method-based commercial tool. The simulation results demonstrate that the suggested sensor has more than 99% relative sensitivity for different types of edible oils at 1.6 THz under ideal geometric conditions. Furthermore, the suggested sensor exhibits low confinement loss, high numerical aperture and effective area at optimal geometry and operational conditions. The proposed sensor is realizable using conventional production procedures and its superior sensing qualities may make it a key component of real-world oil detection systems.

The study aims to reveal the relationship between creative thinking in mathematics and mathematical modeling among university students. The sample consisted of (120) mathematics and engineering students from Yarmouk University and Jordan Science and Technology University, during the summer semester of 2018/2019 academic year, who were selected by cluster sample method. Creative thinking in mathematics and mathematical modeling tests were used. The results showed that the creative thinking in mathematics and mathematical modeling levels among students was moderate. The results also showed a significant differences in mathematical modeling due to the specialization variable in favor of engineering students, while showed no differences due to gender; it's also showed no differences in creative thinking in mathematics due to gender and specialization variables. Moreover, the results showed a strong positive correlations between creative thinking in mathematics and mathematical modeling. According to these findings, the study recommended that students should be given the opportunity to practice creative thinking and mathematical modeling and skills through enriching school curricula and university courses with activities and tasks rich in life situations that require mathematical modeling.

In this study, ultrasonication-assisted calcium carbonate scale inhibition was investigated compared with a commercial antiscalant ATMP (amino tris(methyl phosphonic acid)). The effects of varying ultrasound amplitude, pH, and inhibition duration were evaluated. The inhibition of calcium carbonate scale formation was measured based on the concentration of calcium in the solution after subjecting to different conditions. Scale deposits were also characterized using scanning electron microscopy and X-ray diffraction spectroscopy. Inhibition of scale formation was supported at a pH of 7 for an ultrasound amplitude of 150 W. A 94% calcium carbonate inhibition was recorded when the experiment was carried out with ultrasonication. The use of 5 mg/L ATMP achieved a 90% calcium carbonate inhibition of ATMP. The result of the characterization revealed that the morphology of the crystals was unaffected by ultrasonic irradiation. Sample treatment was performed with two different membranes to evaluate the calcium carbonate deposition, and data reveals that, at identical conditions, ultrasonication provides less deposition when compared to the control experiments.

Poly(ethylene-vinyl acetate) (PEVA) nanocomposite incorporating dual clay nanofiller (DCN) of surface modified montmorillonite (S-MMT) and bentonite (Bent) was studied for biomedical applications. In order to overcome agglomeration of the DCN, the S-MMT and Bent were subjected to a physical treatment prior to being mixed with the copolymer to form nanocomposite material. The S-MMT and Bent were physically treated to become S-MMT(P) and Bent(pH-s), respectively, that could be more readily dispersed in the copolymer matrix due to increments in their basal spacing and loosening of their tactoid structure. The biocompatibility of both nanofillers was assessed through a fibroblast cell cytotoxicity assay. The mechanical properties of the neat PEVA, PEVA nanocomposites, and PEVA-DCN nanocomposites were evaluated using a tensile test for determining the best S-MMT(P):Bent(pH-s) ratio. The results were supported by morphological studies by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Biostability evaluation of the samples was conducted by comparing the ambient tensile test data with the in vitro tensile test data (after being immersed in simulated body fluid at 37 °C for 3 months). The results were supported by surface degradation analysis. Our results indicate that the cytotoxicity level of both nanofillers reduced upon the physical treatment process, making them safe to be used in low concentration as dual nanofillers in the PEVA-DCN nanocomposite. The results of tensile testing, SEM, and TEM proved that the ratio of 4:1 (S-MMT(P):Bent(pH-s)) provides a greater enhancement in the mechanical properties of the PEVA matrix. The biostability assessment indicated that the PEVA-DCN nanocomposite can achieve much better retention in tensile strength after being subjected to the simulated physiological fluid for 3 months with less surface degradation effect. These findings signify the potential of the S-MMT(P)/Bent(pH-s) as a reinforcing DCN, with simultaneous function as biostabilizing agent to the PEVA copolymer for implant application.

Polyaniline (PANI) was chemically doped and functionalized with single walled carbon nanotubes (SWCNTs). Various characterization methods were employed to study the structure and optical properties of PANI/SWCNTs nanocomposite, such as Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), optical absorption, and stationary photoluminescence. Additionally, a theoretical study using density functional theory calculations was also carried out. It has been demonstrated that the doping process may reduce the band gap without affecting the molecular structure, leading to a better compatibility with the solar spectrum. Moreover, the functionalization process with SWCNTs was able to significantly improve the properties of the resulting nanocomposite. The final interpenetrating network of PANI/SWCNTs exhibited an optical gap of nearly 2.28 eV, from which localized states induced by the charge transfer were created at nearly 1.70 eV. In addition, the resulting donor–acceptor network leads to a separation of electron holes pairs rather than their recombination, which can be used as an active layer in photovoltaic applications and a photocatalyst for advanced oxidation processes.

The purpose of this study was to assess the ability of titanium Ti(IV) alkyloxy compounds supported by organic polymer polyvinyl chloride (PVC) to polymerize ethylene by feeding triethylaluminium (TEA) as a cocatalyst. Additionally, the impacts of the molar ratio of [Al]/[Ti] on the catalytic activities in ethylene’s polymerization and of the comonomer through utilization of diverse quantities of comonomers on a similar or identical activity were studied. The optimal molar ratio of [Al]/[Ti] was 773:1, and the prepared catalyst had an initial activity of up to 2.3 kg PE/mol Ti. h. when the copolymer was incorporated with 64 mmol of 1-octene. The average molecular weight (Mw) of the copolymer produced with the catalysts was between 97 kg/mol and 326 kg/mol. A significant decrease in the Mw was observed, and PDI broadened with increasing concentration of 1-hexene because of the comonomer’s stronger chain transfer capacity. The quick deactivation of titanium butoxide Ti(OBu)4 on the polymers was found to be associated with increasing oxidation when supported by the catalyst. The presence of Ti(III) after reduction with the aluminum alkyls cleaves the carbon-chlorine bonds of the polymer, producing an inactive polymeric Ti(IV) complex. The results show that synergistic effects play an important role in enhancing the observed rate of reaction, as illustrated by evidence from scanning electron microscopy (SEM). The diffusion of cocatalysts within catalytic precursor particles may also explain the progression of cobweb structures in the polymer particles.

Our goal is to develop a structural ceramic for high-temperature applications in which silicon carbide-based materials (SiCs) are used as matrix composites. The potential of SiCs to deposit a mixture of SiC and zirconium diboride (ZrB2) plasma spray coating is analyzed. To deposit thermal barrier layers containing up to 50 vol.% SiC, a high-pressure plasma spray (HPPS) process was used. Although the SiC cannot be deposited by thermal spray, a mixture of SiC and zirconium diboride (ZrB2) was deposited because these two compounds form a eutectic phase at a temperature below SiC decomposition. The preference was two different forms, 3 mm and 1 mm, of graphite substrates with different thickness values. A comparison of the morphology of SiC-ZrB2 coatings before and after thermal treatment was performed by applying heat to the surface of a gas torch and traditional furnace between 800 °C and 1200 °C. The growth of the oxide scale was calculated with X-ray diffraction (XRD), scanning electron microscopy (SEM)/energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), and density. The oxide scale consists of a SiO2 layer with ZrO2 groups. The findings indicate a greater potential for the studied material in protecting against high-temperature oxidation and in a wide variety of aerospace applications.

Because of the increased demand for preceramic polymers in high-tech applications, there has been growing interest in the synthesis of preceramic polymers, including polysiloxanes and alumina. These polymers are preferred because of their low thermal expansion, conformability to surfaces over large areas, and flexibility. The primary objective was to evaluate the aspects of polymer-derived ceramic routs, focusing on the UV lithography process of preceramic polymers and the pyrolyzing properties of the final ceramics. We found that the p(DMS-co-AMS) copolymer was effective in scattering the hydrophilic Al2O3 nanoparticles into the exceedingly hydrophobic solvent. The physico-chemical behavior of characterized copolymers was explored during their pyrolytic transformation into amorphous silicon-based ceramics. The results indicate that an increase of the pyrolysis temperature degraded the Si−O network through the carbothermic reaction of silicon. We also found a rapid elimination of copolymer pores and densification when the temperature increased (1100 to 1200 °C). At different but specific temperature ranges, there are different distinct rearrangement reactions in the conversion of polymer to ceramic; reductions of the melting point (Tm) of the total heat of melting (ΔHm) of the pyrolysis process resulted in the crystallization of ceramic materials; hence, lithography based on pyrolysis properties of preceramic polymers is a critical method in the conversation of polymers.

Objectives: The aim of this study is assessment of plasma apelin levels in patients with coronary artery disease (CAD) before and after percutaneous coronary intervention (PCI). Methods: The present study is conducted on 40 patients who underwent PCI, beside 20 healthy subjects with no risk factors or any evidence of CAD. After history taking each subject in the study underwent an electrocardiography, echocardiography for calculation of the left ventricular ejection fraction (LVEF). 22 patients underwent PCI with drug eluting stent (DES), while 18 patients underwent PCI with bare metal stents. Plasma apelin level was estimated for the control group, before, and 24 h after PCI in the patient’s group. Results: Baseline plasma apelin level was higher in the control group versus the PCI group (385.4 ± 94.86 vs. 286.8 ± 52.93 ng/ml, p

Rhizophora spp. wood has the potential to serve as a solid water or tissue equivalent phantom for photon and electron beam dosimetry. In this study, the effective atomic number (Zeff) and effective electron density (Neff) of raw wood and binderless Rhizophora spp. particleboards in four different particle sizes were determined in the 10–60 keV energy region. The mass attenuation coefficients used in the calculations were obtained using the Monte Carlo N-Particle (MCNP5) simulation code. The MCNP5 calculations of the attenuation parameters for the Rhizophora spp. samples were plotted graphically against photon energy and discussed in terms of their relative differences compared with those of water and breast tissue. Moreover, the validity of the MCNP5 code was examined by comparing the calculated attenuation parameters with the theoretical values obtained by the XCOM program based on the mixture rule. The results indicated that the MCNP5 process can be followed to determine the attenuation of gamma rays with several photon energies in other materials.

Background: Patients with Wolff–Parkinson–White (WPW) syndrome are prone to develop a variety of tachyarrhythmias which may lead to unpleasant, disabling symptoms and in extreme, sudden cardiac death (SCD). The aim of our study was to evaluate the clinical significance of corrected QT dispersion (QTcd) as a noninvasive predictor of paroxysmal tachyarrhythmias in patients with WPW syndrome. Patients and methods: The study population comprised 40 patients with WPW syndrome presented to the emergency department by paroxysmal tachyarrhythmias. They were classified into 3 groups; group I: 18 patients presented with regular narrow QRS complex tachycardia, group II: 10 patients presented with regular wide QRS complex tachycardia, group III: 12 patients presented with irregular wide QRS complex tachycardia. All patients were subjected to clinical evaluation, 12-lead electrocardiography (ECG) analysis during the attack of paroxysmal tachyarrhythmia to define its type and after reversion to sinus rhythm for the measurement of QTcd, echocardiography, laboratory investigations and 24-h ambulatory electrocardiographic monitoring. Results: There was a significant increase of QTcd, QTmax, QTmin, Delta wave duration, QRS duration, and QRS amplitude in patients with group III compared to either group I and group II (P

Introduction: The development of ischemic mitral regurgitation (IMR) after myocardial infarction (MI) may impose hemodynamic load during a period of active left ventricular remodeling and promote heart failure (HF). The aim of our study was to evaluate left ventricular (LV) long axis contraction assessed by both mitral annular plane systolic excursion (MAPSE) and peak systolic velocity (Sa) in patients with ischemic MR after acute MI. Methods: Thirty-eight patients with a first attack of acute MI were classified into two groups. Group I comprised 18 patients with MI and ischemic MR, and group II comprised 20 patients with MI without IMR. Twenty age-matched subjects were considered as the control group (group III). Measurement of MAPSE from M-mode tracing of the mitral annulus in apical 4- and 2-chamber view, and pulsed wave tissue Doppler imaging (PW-TDI) of the 4 sides of the mitral annulus for assessment of the Sa velocity were done. Results: A significant decrease of MAPSE was observed in 4 sides in patients with acute MI with IMR compared to MI without IMR and control group (P

Background: Myocardial bridge (MB) is defined as a segment of a major epicardial coronary artery the “tunneled artery” that goes intramurally through the myocardium beneath the muscle bridge. Multiple methods have been proposed to assess coronary flow rate among which thrombolysis in acute myocardial infarction frame count was a relatively new semiquantitative method. Objectives: Our goal was to determine incidence of MB in the patients undergoing coronary angiography in Mansoura Specialized Hospital, Cardiac Catheterization Laboratory, also to investigate the hypothesis that slow coronary flow rate may be linked to angina or angina like symptoms in patients with MB without stenotic lesions in epicardial coronary arteries using TFC. Patients and methods: Fifteen patients with MB (group I) were retrospectively collected from Mansoura Specialized Hospital, Cardiac Catheterization Laboratory, we review 3000 cases referred to diagnostic coronary angiography to exclude significant coronary artery disease. Fifteen patients with normal coronary angiography served as control (group II). We review the clinical presentations, risk factors, echocardiographic data for both test and control groups. TFC was calculated using a simple continuous index. Results: The incidence of MB in our study was 0.5%. CTFC in LAD was significantly higher in the patients with MB compared with control. No significant correlation between TFC and echocardiographic parameters. Conclusions: Myocardial bridging must be considered especially in patients at low risk for coronary atherosclerosis but with angina like chest pain or established myocardial ischemia. We suggest that coronary blood flow is decreased in the patients with MB compared with the patients having normal coronary.

The use of real-time ultrasound (US) is advantageous in the insertion of central venous catheters (CVCs) in adults, especially in whom difficulties are anticipated for various reasons. The aim of the present study was to compare two different real-time 2-dimensional US-guided techniques [short axis view/out-of-plane approach (SAX OOP approach) versus long axis view/in-plane approach (LAX IP approach)] for internal jugular vein (IJV) cannulation. In this prospective study, 90 critical care and hemodialysis patients were assigned for insertion of CVCs using either the real-time US-guided (SAX OOP approach or LAX IP approach) or landmark technique (control group). Failed catheter placement, risk of complications from placement, failure on first attempt at placement, number of attempts until successful catheterization, time to successful catheterization, incidence of central line-associated blood stream infection (CLA-BSI) and demographics of each patient were recorded. There were no significant differences in patient′s demographic characteristics, side of cannulation (right or left) or presence of risk factors for difficult venous cannulation between the three groups of patients. Cannulation of the IJV was achieved in all patients by using US (SAX OOP and LAX IP approaches) and in 27 of the patients (90%) by using the landmark technique (P = 0.045). Average access time (skin to vein) and number of attempts were comparable between the SAX OOP and the LAX IP approaches while significantly reduced in both US groups of patients compared with the landmark group (P

Background and aim: Appropriate assessment and prevention of cardiovascular (CV) disease is one of the most important medical tasks worldwide. Carotid artery intima-media thickness (CIMT) is a marker of atherosclerosis, which has been associated with CV events. We examined the associations of a panel of different clinical, laboratory, and ultrasound variables simultaneously and individually with CIMT; to reveal the presence of additional surrogate markers of atherosclerosis to CIMT. Subjects and methods: 407 Consecutive non-diabetic individuals (220 men) who underwent comprehensive CV evaluation were included. The maximum IMT of the common and internal carotid artery on the right and left side of the neck were recorded by ultrasonography, and CIMT was calculated as the average of the four measurements. Ten-year Reynolds risk score (RRS) for CV events was calculated online for men and women. CAVI was measured using a VaSera vascular screening system, and the averages of the right and left CAVI were used for analysis after being adjusted for age. Results: Univariate linear regression models were constructed to test the association of each of the independent variables with the log-transformed CIMT values [Ln (average CIMT) + 2] separately for men and women. Only the variables with non-adjusted p ⩽ 0.1 were included in the final multivariately-adjusted stepwise linear regression model. After multivariate adjustment, only two variables were significantly and independently associated with log-transformed CIMT values in males (the log-transformed Reynolds risk score and the average age-matched CAVI) and females (the average age-matched CAVI and systolic blood pressure). Conclusion: RRS could be a candidate marker of atherosclerosis in men but not in women, while age-adjusted CAVI could be considered a marker of atherosclerosis in both genders.

Background: Myocardial infarction (MI) results in impairment of left ventricular (LV) systolic and diastolic functions to various degrees. The tissue Doppler image derived Tei index (TDI-Tei index) has recently been used to assess LV function, and like the conventional Tei index, it was also found to be useful for global function. There are a small number of studies which apply TDI-Tei index to assess regional function and whether it varies according to the degree of changes in wall motion in various LV segments. Objectives: This study was conducted to assess the changes of segmental myocardial Tei index by TDI according to the degree of changes of wall motion in the patient with acute ST-segment elevation myocardial infarction (STEMI) and its correlation with Tei index derived by conventional Doppler. Patients and methods: This study was carried out on thirty patients with acute STEMI selected from Coronary Care Unit, Cardiology Department, Mansoura Specialized Hospital, Mansoura University, Egypt. The study group was subjected to clinical assessment, electrocardiography (ECG), routine laboratory profile and Doppler echocardiography (conventional and pulsed wave tissue Doppler imaging “PW-TDI”). Tei index was calculated from the sum of isovolumetric contraction time (IVCT) and isovolumetric relaxation time (IVRT), divided by ejection time (ET) which were measured from pulsed wave Doppler imaging of the trans-mitral inflow and LV outflow tracts. Myocardial velocities and TDI-Tei index were measured at basal and mid-segments of LV walts from apical 4, 2 and 5-chamber views using 16-segment model. Average values of myocardial velocities and TDI-Tei indices were obtained from normal, hypokinetic and akinetic segments then compared. Results: The mean values of left ventricular ejection fraction (LVEF), mitral E/A ratio and conventional Tei index were 51.83 ± 5.15%, 1.18 ± 0.15 and 0.63 ± 0.07 ms, respectively. Segmental myocardial TDI-Tei index was correlated positively with conventional Tei index (r = 0.648, P

Background: To investigate the rate of all cause and cardiovascular mortality in patients with symptomatic or asymptomatic peripheral arterial disease (PAD) compared to those without PAD. Methods and results: All the subjects were inpatients at high risk of atherosclerosis and enrolled from February to November, 2006. A total of 320 were followed up until an end-point (death) was reached or until February 2010. The mean follow-up time was 37.7 ± 1.5 months. Compared with non-PAD, PAD patients had significantly higher rates of hypertension, diabetes mellitus, and smoking (P

In this paper a system for multi-scale change detection with automatic scale selection is proposed. The generation of the multi-scale data set is performed based on the fractal net evolution approach (FNEA). The set of scales used by FNEA are optimally selected from the scale domain ensuring that the selected levels present a good enough representation of the scale domain. A pattern search module is used to select good enough set of scales with the least redundancy. The change detection is performed on each scale individually. For each individual object in a specific scale change indicators are extracted for the pixels corresponding to this object in the base-scale images. After extracting the change indicators for each scale, the extracted indicators are thresholded to obtain a per-scale binary change map. To obtain the final change map, a scale-driven fusion of all the extracted change maps is performed. The fusion is based on detecting for each pixel the preferred scale to obtain its change information. The best scale for an object is the scale where the object area keeps static/almost static while moving from one scale to the next scale(s). The proposed system proves advantageous over other change detection systems.

The purpose of this study is to determine the views of teachers and students on establishing physical education in general secondary certificate examination. Two main areas were investigated: the views of PE teachers, and the students' perceptions of selecting or not selecting PE as an examination subject. Information was obtained from an English school on the logistics of implementing GCSE PE and compared with data gathered from Jordanian schools. Semi-structured interviews and questionnaires were used. The study indicated that PE would be preferred as a GCSE option by Jordanian PE teachers. The main reasons for this were changing the attitudes of Jordanian society, motivate students in pursuing healthy lifestyle as well as providing some professional development for the teachers themselves. The study also showed that if students had negative experiences of PE in the first three grades, they will likely continue to have a negative perception of it through out their school career.