Hanan Hassan Fouad

Partially premixed combustion is characterized by mixture fraction inhomogeneity upstream of the reaction zone and occurs in many applied combustion systems. The temporal and spatial fluctuations of the mixture fraction have tremendous impact on the combustion characteristics, emission formation, and flame stability. In this study, turbulent partially premixed flames are experimentally studied in a slot burner configuration. The local temperature and gas composition is determined by means of one-dimensional, simultaneous detection of Rayleigh and Raman scattering. The statistics of the mixture fraction are utilized to characterize the impact of the Reynolds number, the global equivalence ratio, the progress of mixing within the flame, as well as the mixing length on the mixing field. Furthermore, these effects are evaluated by means of a regime diagram for partially premixed flames. In this study, it is shown that the increase of the mixing length results in a significantly more stable flame. The impact of the Reynolds number on flame stability is found to be minor. © 2018 Taylor & Francis.

One of the most significant consequences of systemic lupus erythematosus (SLE) is lupus nephritis (LN). Visfatin, an adipokine that is significantly expressed in visceral fat and is a marker of endothelial dysfunction in chronic kidney disease, has multiple proinflammatory actions. We aimed to evaluate the state of serum visfatin in SLE patients and to detect its possible correlation with the disease's activity and effects on the kidney affection. Fifty patients with active LN, 50 patients with inactive lupus, and 50 healthy people had their serum visfatin levels tested. Chemical and immunological markers of SLE and LN were measured. The SLE Disease Activity Index (SLEDAI) was used to measure the disease's activity. Renal biopsies from the LN subgroup were collected and classified using the modified classification of the World Health Organization. The serum visfatin of patients with active LN was significantly greater than that of inactive lupus patients and the healthy controls (20.56 ± 1.07 ng/mL, 16.77 ± 1.02 ng/mL, and 9.96 ± 1.46 ng/mL, P <0.001). SLEDAI and serum visfatin levels were shown to be significantly correlated (P = 0.000057). Serum visfatin levels were likewise significantly correlated with the index of histological activity in the active group (P <0.00001). Serum visfatin was raised in individuals with active LN and was related to the SLEDAI and disease severity scores. Serum visfatin could be utilized as a noninvasive biomarker for evaluating the severity of LN and risk stratification of the risk.

Aim: To evaluate shade matching potential of monochromatic layering technique (Filtek Universal) compared to polychromatic layering technique (Filtek Z350XT) in restoration of fractured incisal angle. Materials and Methods: A total of 26 patients received 26 class IV restorations divided randomly between groups (n = 13) using either; monochromatic layering technique (Filtek Universal) or polychromatic layering technique (Filtek Z350XT) in a parallel study design with superiority framework. After preparation, class IV resin composite restorations were performed according to manufacturers’ instructions. Shade matching of class IV restorations was evaluated by two blinded and calibrated assessors using the modified USPHS criteria and digital photography at baseline and after three-days. Association between the layering technique for restoration of fractured incisal angle and shade matching potential was done using the chi square test; statistical significance was set at P ≤ 0.05. Results: Inter-group comparison between layering techniques for shade matching using the modified USPHS criteria have shown statistically significant difference at baseline (P = 0.0001), while there was no statistically significant difference after 3 days (P = 0.2864). Intra-group comparison between follow-up periods within monochromatic layering technique have revealed statistically significant difference (P = 0.0001), while within polychromatic layering technique there was no statistically significant difference (P = 0.2864). Inter-group comparison between both layering techniques using digital photography have shown no statistically significant difference at baseline (P = 0.3592), while after 3 days there was statistically significant difference (P = 0.0071). Intra-group comparison between follow-up periods within monochromatic layering technique have shown statistically significant difference (P = 0.0002), while within polychromatic layering technique there was no statistically significant difference (P = 0.3592). Conclusions: Monochromatic resin composite restorations showed satisfactory shade matching potential when compared to polychromatic resin composite restorations.

This study aimed to evaluate the accuracy of oscillometric blood pressure measurement at the ankle in children using invasive blood pressure as reference standard. This prospective observational study included children undergoing noncardiac surgery. Paired radial invasive and ankle non-invasive blood pressure measurements were obtained. Delta blood pressure was calculated as the difference between two consecutive readings. The primary outcome was the mean bias and agreement between the two methods using the Bland-Altman analysis. The ISO standard was fulfilled if the mean bias between the two methods was ≤ 5 ± 8 mmHg. Other outcomes included the trending ability of ankle blood pressure using the four-quadrant plot and the accuracy of ankle measurement to detect hypotension using area under receiver operating characteristic curve (AUC) analysis. We analyzed 683 paired readings from 86 children. The mean bias between the two methods for systolic, diastolic, and mean blood pressure (SBP, DBP, MAP) was - 7.2 ± 10.7, 4.5 ± 12.8, and - 1.8 ± 8.2 mmHg, respectively. The concordance rate of ankle blood pressure was 72%, 71%, and 77% for delta SBP, DBP and MAP, respectively. The AUC (95% confidence interval) for ankle MAP ability to detect hypotension was 0.91 (0.89-0.93) with negative predictive value of 100% at cut-off value ≤ 70 mmHg, We concluded that in pediatric population undergoing noncardiac surgery, ankle blood pressure was not interchangeable with the corresponding invasive readings with the ankle MAP having the least bias compared to SBP and DBP. An ankle MAP > 70 mmHg can exclude hypotension with negative predictive value of 100%.