Improving the Characteristics of Water-Based Drilling Fluids Using Nanoparticles

The capabilities of different types of nanoparticles (NPs) had been exploited to develop a water-based drilling fluid having better characteristics for harsh drilling conditions. More specifically, the objectives of this work are to: 1) investigate the effectiveness of using different oxide NPs: ferric oxide (of sizes< 50 nm), magnetic iron oxide (of average particle size 50 –100 nm), silica NPs (size =12 nm), and zinc oxide NPs (of sizes < 100 nm) on the rheological properties and filter cake characteristics of Ca-bentonite-based drilling fluid at downhole conditions, 2) conduct a sensitivity analysis of the rheological properties of these drilling fluids and investigate the effect of charge potential, 3) determine the optimum concentration of NPs, and 4) evaluate the effect of different drilling fluid additives on the performance of NPs/Ca-bentonite fluids by formulating and testing a complete bentonite-based drilling fluid formula. A reduction of 43% in the fluid loss volume was achieved when using 0.5 wt% of ferric oxide NPs with 7 wt% Ca-bentonite suspension compared to that without NPs. However, using silica or zinc oxide NPs at different concentrations resulted in an increase in the fluid loss volume and filter cake thickness. The inductively coupled plasma (ICP) analysis of the filtrate fluids and the scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) of the filter cakes revealed the replacement of the cations dissociated from the Ca-bentonite by ferric oxide NPs at the investigated conditions, which promoted the formation of rigid clay platelet structure. Furthermore, using 0.5 wt% of NPs provided less agglomeration, as shown by the SEM images, and less filter cake permeability. Moreover, the produced filter cake consisted of two layers, as indicated by the computed-tomography (CT) scan. Increasing the concentration of NPs resulted in an increase in the fluid loss and filter cake thickness. At high NP concentration (2.5 wt%), a new layer of the agglomerated NPs generated in the filter cake close to the surface of formation, which adversely affected the cake characteristics. The ferric oxide and magnetic iron oxide NPs/Ca-bentonite fluids were found to have stable rheological properties at different NP concentrations and temperatures (up to 200°F). Additionally, thermally aging these fluids at 350°F for 16 hours showed minor changes in their rheological properties, which confirmed their applicability in drilling downhole environments. The ferric oxide NPs improved the filter cake and filtration properties of Ca-bentonite-based drilling fluids in the presence of polymer and other additives under both static and dynamic filtration (at 100 rpm). The best filter cake characteristics were obtained when using a NP concentration of 0.3-0.5 wt%. Furthermore, the formulated NPs/Ca-bentonite-based drilling fluids could withstand downhole conditions up to 500 psi and 350°F and produced a filter cake that has 0.151-in. thickness, 6.9 ml filtrate loss volume, and 0.428 µd permeability at this conditions. Moreover, it was noticed that the ultrasonication for at least one hour and bentonite hydration for 16 hours are recommended for better preparation of the formulated ferric oxide NPs/Ca-bentonite-based drilling fluid

The influence of mineralogical composition and alkali reactivity for utilization of some Egyptian crushed granites as a concrete aggregate

Egyptian Eastern Desert is rich in many areas that contain granites masses throughout the geological era; some of them show good characteristics of the rock hardness, durability, density and mineralogy. This current research aims to utilize three main types of granite aggregates based on their mineralogical composition and Alkali reactivity with cement during concrete production. The studied granite aggregate can be also classified into red younger granite aggregate, white older granite aggregate and grey older granite aggregate. Evaluating these granite rocks as aggregate used in concrete mixture is interesting by produced three mixes using the three studied granite aggregate symbolized (Red GA), (White GA) and (Grey GA), tested mechanically to give a more detailed for the obtained results to be not restricted for only studied granite aggregate criteria but also to follow the actual reaction of this studied granite aggregate with cement.&nbsp;&nbsp; It was obtained that all studied granite aggregates within acceptable limits of concrete aggregate by following Egyptian code (ECP-203) although their variation on its mineralogical composition. Some reflections produced from change in mineralogical composition between the three studied granite aggregates exhibited by relative regression in the average physico-mechanical values for both (White and Grey GA) than (Red GA). On the other hand, slight reactive for (Red GA) than others at the age of 28 day. In addition, all produced (Red GA), (White GA) and (Grey GA) mixes were acceptable mechanically with limits of (ECP-203) giving benefit for using all of the studied granite aggregate after their detailed study involving its mineralogical composition and alkali aggregate reactivity (AAR)

Transversus abdominis plane (TAP) block: Review article

Background: The transversus abdominis plane (TAP) block is a localized analgesic method for the abdomen wall on the anterolateral side. Ultrasound (US) guided TAP blocks are currently regarded as the gold standard. It is simple to obtain US images; it could be utilized in several surgical procedures including the abdominal wall on the anterolateral side. Though, US-guided TAP blocks’ effectiveness varies, that may be owing to the variety of techniques used. The approach chosen has an effect on the area included and the duration of the block. To examine the true analgesic consequences of TAP blocks, we standardized the nomenclature system and defined all methods. While a single-shot TAP block has a restricted period, it remains an applicant for the analgesia threshold for abdominal wall operation due to the possibility of overcoming this restriction using the catheter method and liposomal bupivacaine. TAP blocks could be used more effectively to attain improvement of pain control with an integrated nomenclature and the advance of catheter method and/or local liposomal analgesics. Objective: This review discusses the nomenclature system and current improvements in TAP block approaches. Methods: The databases were searched for articles published in English in 4 data bases [PubMed – Google scholar- Egyptian bank of knowledge -Science direct] and Boolean operators (and, or, not) had been used such as [Transversus abdominis plane block AND Internal Oblique Muscle OR Ultrasound guided] and in peer-reviewed articles between January 2000 and August 2021.Conclusion: With the improvement in US method, the successful rate and protection of TAP blocks have clearly enhanced

EXAMINING THE EFFECT OF HIGH SEASONALITY ON FRONTLINE EMPLOYEES: A CASE STUDY OF FIVE STARS HOTELS IN AQABA

In recent times, the impact of seasonality on tourism industry has been recognized. There has been a distinct lack of studies that focus on the effects of high seasonality on front-line employees (the receptionist) in hotels. Therefore, this study attempted to address the importance of the receptionist job in high seasonality and the effect of high seasonality on them. To answer the questions of the study, an instrument was used for evaluation. Also, a questionnaire was addressed to both employees and managers. T-test, ANOVA, and multiple regressions were utilized to test the hypotheses. The findings of the study revealed that the high seasonality in hotels has effects on the receptionists regarding miscommunication and bad relation with others during work hours. Therefore, this study has several recommendations for both the managers and the enterprises

Local injection of autologous platelet rich plasma and corticosteroid in treatment of lateral epicondylitis and plantar fasciitis: Randomized clinical trial

AbstractAim of the workThis randomized controlled study was designed to compare the effectiveness of local injection of autologous platelet rich plasma (PRP) and local steroid in reducing pain and improving function in a cohort of patients with tennis elbow (TE) and plantar fasciitis (PF).Patients and methodsThe study population comprised two groups; Group 1 patients with TE (n=30) and Group 2 patients with PF (n=30). In each group patients were allocated randomly to receive either a steroid or PRP injections. All patients filled in visual analog scale (VAS), disability of arm, shoulder and hand (DASH) score for TE and foot health status questionnaire (FHSQ) for PF at base line and after 6weeks.ResultsRelative to TE group of patients significant differences were observed between VAS and DASH scores at base line and 6weeks after treatment in both groups (p<0.001). While no significant differences were observed relative to VAS and DASH score changes between both groups (p>0.05). In PF patients comparison of VAS and FHSQ at base line and 6weeks after treatment between control group and PRP group showed significant differences for VAS (p=0.005 and p<0.001, respectively), and for FHSQ (p=0.03 and p<0.001, respectively). While highly significant difference were observed between both groups regarding VAS and FHSQ changes (p=0.001).ConclusionLocal injection of autologous PRP proved to be a promising form of therapy for TE and PF. It is both safe and effective in relieving pain and improving function and superior to local steroids in PF

Nonalcoholic Fatty Liver Disease and the Risk of Atrial Fibrillation

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is now the factor behind the development of liver cirrhosis, liver cell failure, and liver transplantation in many cases. However, its relation to atrial fibrillation (AF) could not be cleared up. AIM: The purpose of the study was to evaluate prevalence of AF in the setting of NAFLD; the association between them, and to evaluate risk factors of AF in this category of patients. METHODS: This cross-sectional study was performed on 400 patients between January 2018 and June 2019. These patients were analyzed for the presence of NAFLD and presence of persistent or chronic AF. RESULTS: There were 138 patients with NAFLD, and 20 patients with persistent or permanent AF. Factors associated with AF were old age, male gender, and high values of aspartate aminotransferase, alanine-aminotransferase, γ-glutamyltranspeptidase, and serum uric acid. The participants with AF had a significantly greater prevalence of NAFLD than those without AF. CONCLUSION: Incidence and prevalence of atrial fibrillation in NAFLD patients were high. Severity of liver disease was an important predictor of new-onset atrial fibrillation

Endovenous Laser Ablation, Radiofrequency Ablation and Flebogrif versus Conventional Surgery in Treatment of Primary Varicose Vein of the Lower Limb: Prospective Randomized Controlled Study

Background: Endovenous laser ablation (EVLA), radiofrequency ablation (RFA) and mechanochemical ablation (MOCA) of primary varicose vein are thought to minimise postoperative morbidity and reduce work loss compared with the conventional surgical procedure. Objective: To determine, whether endovenous ablation methods (radiofrequency, laser and mechanochemical) have any advantages or disadvantages in comparison with conventional surgery, in the treatment of primary varicose vein. Patients and Methods: This was a prospective randomized study, conducted on forty patients presented at Vascular Outpatient Clinic for management of chronic venous insufficiency. All patients underwent clinical examination and duplex ultrasonography. Ten (10) patients were treated with ligation and stripping of the great saphenous vein (GSV). Ten (10) patients were treated with radiofrequency ablation. Ten (10) patients were treated with endovenous laser ablation. Ten (10) patients were treated with Flebogrif. Results: Compared with conventional surgery, endovenous ablation methods reduced postoperative discomfort and pain, with a lower complication rate after treatment for avoidance of a groin incision and dissection at the saphenofemoral confluence. Cosmetic demands were also better satisfied. Non-controlled clinical trials have shown that the ablation rate of GSV after EVLA is over 90%. However, risks of EVLA, RFA and Flebogrif remain in terms of recanalization and neoreflux via junctional tributaries. Conclusion: RFA, EVLA, and Flebogrif are minimally invasive procedures. Their potential early benefits, by avoiding groin dissection and GSV stripping, have been confirmed by the findings from this trial. Current evidence based on randomized trials consistently demonstrates significant early benefits after RFA, EVLA and Flebogrif in suitable patients with varicose veins