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Objective: To assess the diagnostic efficacy of integrating B-mode and color Doppler capabilities of ultrasound (US) to establish a robust standalone diagnostic tool for the diagnosis of ureteric stones as an alternative to non-contrast-enhanced computed tomography (NCCT). Methods: A total of 140 consecutive patients diagnosed with ureteric stones using NCCT were enrolled. On the same day, US in both B-mode and Color Doppler was performed by an experienced radiologist who was blinded to the NCCT scan results. The diagnostic rate of US for stone detection was recorded. Additionally, baseline patient and stone characteristics were analyzed for their association with the accuracy of stone detection using US. Results: US exhibited a high sensitivity of 91.43%, detecting 128 out of 140 stone foci. Notably, ureteric stones in the proximal and uretero-vesical junction (UVJ) segments were readily identifiable compared to those in the pelvic region (p = 0.0003). Additionally, hydronephrosis enhanced the US's ability to detect stones (p < 0.0001). Conversely, abdominal gases and obesity adversely affected US capabilities (p < 0.0001 and p = 0.009, respectively). Stone side, size, and density showed no statistically significant impact (p > 0.05). Conclusions: US with its color Doppler capabilities could serve as a reliable and safe alternative imaging modality in the diagnostic work up of patients with ureterolithiasis. Factors including stone location, Hydronephrosis, weight and abdominal gases significantly influenced its accuracy.

Objective: To analyze the static and dynamic urodynamic parameters of reservoirs and continent conduits in continent cutaneous urinary diversion with catheterizable stoma. Materials and methods: 76 patients had augmented ileocystoplasty or continent urinary diversion with catheterizable urinary stoma based on Mitrofanoff principle and Yang-Monti procedure using subserous tunnel as continence mechanism. They were followed up for at least 6 months post-operatively for continence through stoma and divided into two groups (continents vs non-continent) according to stomal continence. Both groups had urodynamic assessment performed via the stoma to assess reservoir capacity, pressure and contractions, efferent limb functional length, reservoir overactivity, static and dynamic maximal closure pressures and leak point pressure. Results: Continence rate was 87%. Continent group included 66 patients and incontinent group included 10 patients. In both groups at rest, the reservoir pressure after filling did not exceed 25 cm H2O. During peristaltic contraction, the pressure did not exceed 30 cm H2O and the duct remained continent. After Valsalva maneuver, the reservoir pressure increased up to 34 (+ 7.4) cm H2O and leakage occur in 10 patients (13%). Reservoir (wall) overactivity was recorded in 54 patients, with insignificant rise in intraluminal pressure during the contractions. In both groups, the efferent tract closing pressure was always higher than the reservoir pressure. The mean of maximal closing pressure at Valsalva was 82.5 (+ 4.18) cm H2O in the continent group and 61.66 (+ 8.16) cm H2O in the incontinent group. The mean functional length of the conduit was 4.95 + 1.62 in the continent group and 2.80 + 1.50 cm in the incontinent group. Conclusions: Urodynamic evaluation of continent catheterizable cutaneous stoma after Yang-Monti procedure has a practical significance. Functional length of the conduit seems to be the most influential factor for continence reflecting static & dynamic maximal closure pressure. Higher conduit closing pressure is associated with better continence. Contractions of the pouch and peristaltic contraction of the conduit has no effect on continence mechanism.

The present study evaluated for the first time, some strength properties and the chemical compositions of seven hardwood species grown in Northeast Egypt, namely, Acacia saligna, Delonix regia, Erythrina humeana, Ficus elastica, Leucaena leucocephala, Melia azedarach, and Meryta sinclairii. The analysis of variance (ANOVA) results indicated that the effect of wood species on the mechanical properties and chemical compositions was significant (P<0.01). The parameters used to describe the mechanical properties and chemical compositions of the wood of the seven species differed from one species to another. The cellulose contents of the studied species, except for L. leucocephala (43.2%), M. azedarach (44.1%), and M. sinclairii (44.0%), were found to be lower than those of common hardwood species. The variations in MOR, MOE, Cmax, and tensile strength among the seven species were expected given the differences in wood density and chemical compositions. Except for E. humeana, the other hardwood species studied could be considered to have moderate hardness and are suitable for making floor parquets. Overall, based on the studied mechanical properties, the wood of M. azedarach and M. sinclairii showed good MOR, MOE, and Cmax values, whereas E. humeana wood had the lowest such values. In terms of mechanical properties, the seven hardwood species studied in the present investigation can thus be concluded to have the following order: M. azedarach > M. sinclairii > L. leucocephala > D. regia > F. elastica > A. saligna > E. humeana. [ABSTRACT FROM AUTHOR]

Seven varieties of vine prunings (Vitis vinifera L.) grown under Riyadh conditions were considered as renewable sources for fuelwood. Significant effects (P<0.01) were found for total extractives, benzeneethanol extractives, cellulose, hemicellulose, lignin, cold water solubility, and hot water solubility among the seven vine varieties. Highly significant positive correlations (P<0.01) were observed between the higher heating value (HHV) and benzene-ethanol extractives (r=0.74) and lignin content (r=0.94). Additionally, elemental composition (C, H, N, O, and S) exhibited a significant effect on HV (P<0.01) and ash content of the seven vine varieties. There were highly significant positive correlations (P<0.01) between the HV and C (r=0.96) and H (r=0.93). Ash content showed a highly significant effect (P<0.01) on HV with a negative coefficient (r=-0.93). The heating value of vine prunings ranged from 18.74 to 19.19 MJ/kg, i.e. higher than some well-known biomass fuels. The results suggested that the vine prunings could be suitable as a source for energy production in Saudi Arabia. [ABSTRACT FROM AUTHOR]

This study investigated the possibility of using the prunings of six locally grown tree species in Saudi Arabia for cement-bonded particleboard (CBP) production. Panels were made using four different wood particle sizes and a constant wood/cement ratio (1/3 by weight) and target density (1200 kg/m3). The mechanical properties and dimensional stability of the produced panels were determined. The interfacial area and distribution of the wood particles in cement matrix were also investigated by scanning electron microscopy. The results revealed that the panels produced from these pruning materials at a target density of 1200 kg m(-3) meet the strength and dimensional stability requirements of the commercial CBP panels. The mean moduli of rupture and elasticity (MOR and MOE) ranged from 9.68 to 11.78 N mm2 and from 3952 to 5667 N mm2, respectively. The mean percent water absorption for twenty four hours (WA24) ranged from 12.93% to 23.39%. Thickness swelling values ranged from 0.62% to 1.53%. For CBP panels with high mechanical properties and good dimensional stability, mixed-size or coarse particles should be used. Using the tree prunings for CBPs production may help to solve the problem of getting rid of these residues by reducing their negative effects on environment, which are caused by poor disposal of such materials through direct combustion process and appearance of black cloud and then the impact on human health or the random accumulation and its indirect effects on the environment.