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This article aims to describe the effect of an endoscope and heat transfer on the peristaltic flow of a Jeffrey fluid through the gap between concentric uniform tubes.

The mathematical model of the present problem is carried out under long wavelength and low Reynolds number approximations. Analytical solutions for the velocity, temperature profiles, pressure gradient and volume flow rate are obtained.

The results indicate that the effect of the wave amplitude, radius ratio, Grashof number, the ratio of relaxation to retardation times and the radius are very pronounced in the phenomena. Also, a comparison of obtaining an analytical solution against previous literatures shows satisfactory agreement.

Analytical solutions for the velocity, temperature profiles, pressure gradient and volume flow rate are obtained. Numerical integration is performed to analyze the pressure rise and frictional forces on the inner and outer tubes.

This study aims to focus on the main materials used in consolidation processes of illuminated paper manuscripts and leather binding.

For each material, chemical structure, chemical composition, molecular formula, solubility, advantages, disadvantages and its role in treatment process are presented.

This study concluded that carboxy methyl cellulose, hydroxy propyl cellulose, methyl cellulose, cellulose acetate, nanocrystalline cellulose, funori, sturgeon glue, poly vinyl alcohol, chitosan, chitosan nanoparticles (NPs), gelatin, aquazol, paraloid B72 and hydroxyapatite NPs were the most common and important materials used for the consolidation of illuminated paper manuscripts. For the leather bindings, hydroxy propyl cellulose, polyethylene glycol, oligomeric melamine-formaldehyde resin, acrylic wax SC6000, pliantex, paraloid B67 and B72, silicone oil and collagen NPs are the most consolidants used.

Illuminated paper manuscripts with leather binding are considered one of the most important objects in libraries, museums and storehouses. The uncontrolled conditions and other deterioration factors inside the libraries and storehouses lead to degradation of these artifacts. The brittleness, fragility and weakness are considered the most common deterioration aspects of illuminated paper manuscripts and leather binding. Therefore, the consolidation process became vital and important to solve this problem. This study presents the main materials used for consolidation process of illuminated paper manuscripts and leather bindings.

This paper aims to present the components' characterization and condition assessment of an important deteriorated Mamluk-illuminated paper manuscript housed in Al-Azhar Library, Egypt.

Different analytical techniques used in this study were the portable digital optical microscope, stereomicroscope, scanning electron microscope with EDX (SEM.EDX), portable X-ray fluorescence (pXRF), X-ray diffraction (XRD), pH measurement and Fourier transform infrared spectroscopy (FTIR).

The results obtained by different microscopes showed that the gilding in the surface of illuminated paper sheets was performed with gold leaves. Additionally, these microscopes revealed that the illuminated paper manuscript has different aspects of deterioration such as adhered dirt, staining, some micro-cracks, cracks and detachment of some parts in some illuminated areas. The results of elemental analysis by EDX, portable XRF and XRD analysis showed that the orange red pigment is red lead (Pb₃O₄), blue pigment is azurite (2CuCo₃.Cu (OH)₂), and the gold layer is has consisted of brass alloy (Cu-Zn) with a small amount of gold element (Au). The pH measurement stated that the historical paper in the acidity level. The ATR-FTIR analysis also revealed the oxidation of cellulose. Moreover, it was found from ATR-FTIR that Arabic gum was used as a binder for the pigments.

This study presents the important results of analytical methods used for condition assessment and identification of the components of an important Mamluk-illuminated paper manuscript, where these results referred that the studied paper manuscript had different aspects of deterioration. The conservation steps either conservation treatment or preventive conservation are urgently needed in future studies.

The purpose of this paper is to study the research experience of PhD students of Ferdowsi University of Mashhad and factors influencing this experience.

The information was gathered through a questionnaire which has been developed based on PREQ questionnaire. The statistical populations of this study consist of those PhD students whose research proposal had been approved by the educational council of their faculty or had defended their dissertation. By using random sampling method, 118 questionnaires were collected.

The findings showed that there is a significant relationship between all of the research experience factors and significant differences between overall satisfactions of the students on their research experience. Variables such as sex and different stages of research have positive and significant impact on the research experience of the respondents.

The outcomes of this study suggest that among the PhD students of Ferdowsi University, there is a relative satisfaction with factors making up the research experience.

This study is to examine the impact of viscous dissipation, thermal radiation and Ohmic heating on the magnetohydrodynamic (MHD) flow with thermal and mass transport over a horizontally stretching surface. Cattaneo–Christov heat flux model on a non-Newtonian viscous fluid along with two viscosity models and convective boundary condition has been employed. Tri-hybrid nanofluid has been used to increase thermal performance.

Governing mathematical model has been transposed into a dimensionless system of ordinary differential equations (ODEs) by applying suitable similarity transformation. Numerical solution has been found by applying the bvp4c shooting method in MATLAB software.

Velocity and thermal profiles of Model-I dominate the profiles of Model-II whereas opposite behavior is noticed for concentration profiles. It is concluded that there is an increase in temperature due to thermal radiation, viscous dissipation and convective boundary condition.

The novelty of presented work is to examine the impact of Ohmic heating, viscous dissipation, thermal radiation, chemical reaction and two models of viscosity on Cattaneo–Christov heat flux model of tri-hybrid non-Newtonian nanofluid with convective boundary constraint. The accuracy and effectiveness of presented model have been compared with already published research.

Many industries use non-Newtonian ternary hybrid nanofluids (THNF) because of how well they control rheological and heat transport. This being the case, this paper aims to numerically study the Casson-Williamson THNF flow over a yawed cylinder, considering the effects of several slips and an inclined magnetic field. The THNF comprises Al₂O₃-TiO₂-SiO₂ nanoparticles because they improve heat transmission due to large thermal conductivity.

Applying suitable nonsimilarity variables transforms the coupled highly dimensional nonlinear partial differential equations (PDEs) into a system of nondimensional PDEs. To accomplish the goal of achieving the solution, an implicit finite difference approach is used in conjunction with Quasilinearization. With the assistance of a script written in MATLAB, the numerical results and the graphical representation of those solutions were ascertained.

As the Casson parameter β increases, there is an improvement in the velocity profiles in both chord and span orientations, while the gradients Re1/2Cf,Re1/2C¯f reduce for the same variations of β. The velocities of Casson THNF are greater than those of Casson-Williamson THNF. Approximately, a 202% and a 32% ascension are remarked in the magnitudes of Re1/2Cf and Re1/2C¯f for Casson-Williamson THNF than the Casson THNF only. When velocity slip attribute S1 jumps to 1 from 0.5, magnitude of both F(ξ,η) and Re1/2Cf fell down and it is reflected to be 396% at ξ=1, Wi=1 and β=1. An augmentation in thermal jump results in advanced fluid temperature and lower Re−1/2Nu. In particular, about 159% of down drift is detected when S2 taking 1.

There is no existing research on the effects of Casson-Williamson THNF flow over a yawed cylinder with multiple slips and an angled magnetic field, according to the literature.

β-Carotene is the most appropriate and significant precursor of vitamin A. Synthetic carotene supplements have been known to pose a threat to human health, making natural sources such as the indefensible choice for the production and extraction of carotene.

This study considers Blakeslea trispora, a filamentous fungus, as a source of production of carotenoids by fermentation and wet and dry mycelium were used to analyse and obtain better extraction results.

In this study, natural oils such as soy oil and cottonseed oil were incorporated into fermentation media to increase the production of carotene. For the optimization process, Plackett–Burman and one-factor-at-a-time (OVAT) models were identified as being of great value.

OVAT was carried out for corn starch because it plays a major role in the production of carotene and the corn starch at 30 g/L concentration has shown the maximum activity of 3.48 mg/gm. After optimizing process variables, submerged fermentation was eventually carried out under highly controlled media conditions. The resulting product was quantified using UV spectroscopy and extraction of carotene has been observed in the presence of various solvents. Among a range of solvents used, the methylene Di chloride produced-carotene at 86% recovery at a significantly lower temperature of 35°C.

This study aims to explore the intermediate role of self-differentiation in anger management and neurotic perfectionism for a sample of high achievers at some public universities in Egypt and Saudi Arabia. This increases the chances of these students obtaining their rights.

The researcher used the microcopy of Drake, Murdock, Marszalek and [(the Differentiation of Self Inventory—Short Form (DSI-SF)] scale, differentiation of self child-adolescent perfectionism scale and Davidson and Munro (2000) scale of neurotic perfectionism in addition to the anger management scale of the current study. The researcher used the appropriate statistical methods and the descriptive design to find the results.

The results showed that there is no statistically significant difference among male and female students in the positive anger management while three was a statistically significant difference among them in the negative anger management favoring male students. Further, there were no statistically significant differences among the study sample according to the country (Egypt and Saudi Arabia) in anger management (positive and negative). Moreover, there was a correlation matrix between the study variables as shown in the study; The statistical analysis was conducted to identify the suggested constructive model and variables of the study, anger management (positive-negative) as an independent variable, self-differentiation as an intermediate variable and neurotic perfectionism as a dependent variable among high achievers, This explains the necessity of preparing the environment for these students to become more healthy, through which they can enjoy all their rights as a category of special education, where most of the focus is on the handicapped groups from special education more than the high achievers’ students.

The study recommended that higher education courses should focus on anger management skills and the development of self-differentiation and the positive part of perfectionism. Also, the current study provided the educators of higher education with some suggestions to promote it and develop high achievers, which may lead to positive mental and physical health for high achievers and raising awareness of society and obtaining their rights in education and life.

The purpose of this paper is to explore the existing literature on the relationship between different service attributes and patient satisfaction at outpatient nutrition clinics to propose and test a culture-specific conceptual model interlinking the drivers of patient satisfaction.

Over a 7-week period in Fall 2019 (November 2–December 19), 600 patients from a Lebanese-Middle Eastern hospital (396 females and 204 males) completed an anonymous-designed survey with closed questions (n = 30). Statements were considered to represent specific attributes of nutrition services. In order to measure the existence and degree of significant relationships between different research variables, Pearson correlation coefficients and Fisher's Z test were employed to analyze the collected data, before and while joining the clinic, during and after the appointment. Means of scores and frequencies were calculated.

The results show that the nutrition service attributes with reference to “after the appointment” may improve the patients' satisfaction level more than attributes with reference to “while joining the clinic” and “during the appointment”. Most patients were satisfied with their overall outpatient clinic experience. The patient experience is a direct result of positive interactions with the entire services offered.

The conceptual model sets the foundations for testing and for further research to develop. Moreover, the findings of this study are important for assessing the quality of nutrition service attributes and for reporting on the ability of this service to meet the needs and preferences of patients in the health care sector.

This study attempts to fill the gap in knowledge on nutrition service quality as indicators for overall patient satisfaction, while opening clear research avenues for further studies to follow. It is the basis for the development of clinical practice guidelines and other quality enhancement tools.

The oil and gas construction projects are affected negatively by the drop in oil price in recent years. Thus, most engineering, procurement and construction (EPC) companies are opting to optimize the project mainly to mitigate the source of risks in construction to achieve the project expectation. Risk factors cause a threat to the project objectives regarding time, cost and quality. It is additionally a vital component in deviating from the client's expectation of productivity, safety and standards. This research aims to investigate the causes of risk in the oil and gas construction projects in Yemen.

A comprehensive literature review from various sources including books, conference proceedings, the Internet project management journals and oil and gas industry journals was conducted to achieve the objectives of this study. This initial work was predicated strictly on a literature review and the judgments of experts to develop the risk factor framework for the oil and gas construction projects in Yemen.

The authors found a few studies related to risk factors in oil and gas construction projects and shared a similar view about general construction projects. However, only a fraction of the factors accepted have included the variances of other studies on a regional basis or specific countries, such as the Yemen situation, due to the differences between the general construction industry and oil and gas industry. Moreover, the factors of these attributes were still accepted due to their applicability to the oil and gas industry, and no significant variances existed between countries. Research has indicated that 51 critical factors cause risks in the oil and gas construction projects in Yemen. Such risk factors can be divided into two major groups: (1) internal risk factors, including seven critical sources of risks, namely client, contractor, consultant, feasibility study and design, tendering and contract, resources and material supply and project management; and (2) external risk factors, including six sources of critical risk factors, namely national economic, political risk, local people, environment and safety, security risk and force-majeure-related risk factors. A risk factor framework was developed to identify the critical risk factors in the oil and gas construction projects in Yemen.

This research was limited to the oil and gas construction projects.

Practically, this study highlights the risk factors that cause a negative effect on the success of oil and gas construction projects in Yemen. The identification of these factors is the first step in the risk management process to develop strategic responses for risks and enhance the chances of project success.

The identification of risks factors that cause the failure of construction projects helps develop response strategies for these risks, thereby increasing the chances of project success reflected in the oil and gas sector, which is a main tributary of the national economy in developing countries.

This research is the pioneer for future investigations into this vital economic sector. Given the lack of resources and studies in the field of construction projects for the Yemeni oil and gas sector, the Yemeni government, oil companies and researchers in this field are expected to benefit from the results of this study. The critical risk factors specific to the oil and gas construction projects in Yemen should be further investigated with focus only on Yemen and its oil and gas industry players.