Recent burgeoning development in material science has introduced a 3D-printable, nanohybrid composite resin restorative material. However, its performance has not yet been investigated. This study evaluates the stain susceptibility and efficacy of different stain removal techniques. A total of 120 labial veneers were fabricated using milling ( = 60) and SLA 3D-printing ( = 60). Based on the immersion media: coffee, tea and artificial saliva, each group was divided into three sub-groups ( = 20). Stain susceptibility was evaluated by calculating color difference (∆E) at 12 and 24 days using a spectrophotometer against black and white backgrounds. Collected data were analyzed with ANOVA and Tukey's post hoc test ( < 0.05). A significant interaction effect was found between the staining mediums and fabrication methods in both black and white backgrounds ( < 0.001). 3D-printed restorations showed significantly higher stain susceptibility than milled restorations ( < 0.001). Prolonged immersion time increased the color difference in both groups. In-office bleaching was more effective in stain removal in both 3D-printed and milled restoration groups. The susceptibility of the presented novel 3D-printed restorative material to color changes in different immersion mediums was clinically not-acceptable. The clinicians might expect the need to replace the restoration after 1-2 years and thus, recommendation for the use of such a material as a permanent restoration cannot be made but rather as a long-term temporary restoration.

BACKGROUND: Improving stroke services is critical for reducing the global stroke burden. The World Stroke Organization-World Health Organization- Commission on Stroke conducted a survey of the status of stroke services in low and middle-income countries (LMICs) compared to high-income countries.

METHODS: Using a validated World Stroke Organization comprehensive questionnaire, we collected and compared data on stroke services along four pillars of the stroke quadrangle (surveillance, prevention, acute stroke, and rehabilitation) in 84 countries across World Health Organization regions and economic strata. The World Health Organization also conducted a survey of non-communicable diseases in 194 countries in 2019.

RESULTS: Fewer surveillance activities (including presence of registries, presence of recent risk factors surveys, and participation in research) were reported in low-income countries than high-income countries. The overall global score for prevention was 40.2%. Stroke units were present in 91% of high-income countries in contrast to 18% of low-income countries (p < 0.001). Acute stroke treatments were offered in ∼ 60% of high-income countries compared to 26% of low-income countries (p = 0.009). Compared to high-income countries, LMICs provided less rehabilitation services including in-patient rehabilitation, home assessment, community rehabilitation, education, early hospital discharge program, and presence of rehabilitation protocol.

CONCLUSIONS: There is an urgent need to improve access to stroke units and services globally especially in LMICs. Countries with less stroke services can adapt strategies from those with better services. This could include establishment of a framework for regular monitoring of stroke burden and services, implementation of integrated prevention activities and essential acute stroke care services, and provision of interdisciplinary care for stroke rehabilitation.

Based upon the Stokes micro-continuum theory, the problem of lubrication of finite hydrodynamic journal bearing lubricated by magnetic fluids with couple stresses is investigated. By taking into account the couple stresses due to the microstructure additives and the magnetic effects due to the magnetization of the magnetic fluid, modified Reynolds equation is obtained. The effects of couple stresses are studied by defining the couple stress parameter L that can be considered as a measure of the chain length of the additive molecule. The magnetic effects of the magnetic fluid are investigated by the magnetic coefficient γ. Using the finite-difference technique and for different values of couple stress parameter and magnetic coefficient, the Reynolds equation is solved, and pressure distributions are obtained. The bearing static characteristics namely load carrying capacity, attitude angle, friction coefficient, and side leakage flow are determined. The results indicate that the influence of couple stresses and magnetic effects on the bearing characteristics are significantly apparent. It is concluded that fluids with couple stresses are better than Newtonian fluids. The improvement of the bearing characteristics is enhanced if the magnetic effects are present.

Background: Stent underexpansion is a major risk factor for in-stent restenosis and acute in-stent
thrombosis1Intravascular ultrasound (IVUS) is one of the standards for detection of stent underexpansion
(de Feyter et al. 1999; Mintz et al., 2001). StentBoost (SB) enhancement allows an improved angiographic
visualization of the stent (Koolen et al., 2005).
Aim of work: Comparison of stent expansion by IVUS and SB enhancement and detection of value of SB to
guide dilatation post stent deployment.
Methodology: IVUS, SB enhancement and QCA were done in 30 patients admitted for elective stenting
procedures .We compared measurements of mean ±standard deviations of (Max SD, Min SD, Mean SD,
stent symmetry index) using IVUS, SB and QCA after stent deployment and after postdilatation whenever
necessary to optimize stent deployment. The Stent symmetry index was calculated [(maximum stent diameter
minus minimum stent diameter) divided by maximum stent diameter].
Results: The Max SD was (3.45 ± 0.62 vs 3.55 ± 0.56 vs 2.97 ± 0.59) by IVUS vs SB vs QCA respectively. Max
SD was significantly higher by IVUS vs QCA (p .009) and between SB vs QCA (p .001) while there was nonsignificant
difference between IVUS vs SB (p .53). The Min SD was (2.77 ± 0.53 vs 2.58 ± 0.56 vs 1.88 ±
0.60) by IVUS vs SB vs QCA respectively. Min SD was significantly higher by IVUS vs QCA (p .001) and
between SB vs QCA (p .001) while there was nonsignificant difference between IVUS vs SB (p .07). The
stent symmetry index was (0.24 ±0.09 vs 0.34 ± 0.09 vs 0.14 ±0.27) by IVUS vs SB vs QCA respectively.
It was significantly higher by IVUS vs QCA (p .001) and between SB vs QCA (p .001) while there was nonsignificant
difference between IVUS vs SB (p .32). SB was positively correlated with IVUS measurements
of Max SD (p < .0001 & r 0.74) and Min SD (p < .0001 & r 0.68). QCA was positively correlated with IVUS
measurements of Max SD correlation (p < .0001 & r 0.69) and Min SD (p < .0001 & r 0.63). QCA was positively
correlated with SB measurements of Max SD (p < .0001 & r 0.61) and Min SD (p .003 & r 0.49).
Conclusions: StentBoost enhancement has superior correlations for stent expansion measured by IVUS
when compared with QCA. SB enhancement improved stent visualization and identification of stent
underexpansion to guide stent postdilatation.

In this study, Aspergillus terreus was irradiated by a 7.3 mW He-Ne laser in the presence of crystal violet, toluidine blue O and hematoporphyrin as photosensitizers. Xylanases recovered from non-irradiated and irradiated fungi were purified and characterized. The maximum production of xylanase (42.2 U/ml) was obtained after 5 min of laser irradiation in the absence of the photosensitizer. The irradiation of the sensitized fungus diminished the production of xylanase. On purification using G-100, the specific activity of xylanase recovered from the irradiated fungus was 292 U/mg protein representing a 37-fold purification over the crude extract compared with 95.6 U/mg protein representing the 12.8-fold for the enzyme recovered from the non-irradiated fungus. The enzyme recovered from the irradiated fungus had lower molecular weight as compared with that recovered from the non-irradiated one. Characterization of the purified enzymes revealed that the enzyme recovered from the irradiated fungus was more thermostable and had a wider range of optimum reaction temperature (60-70 degrees C) and pH (4.0-12.0), compared to the non-irradiated one.

In this study, Aspergillus terreus was irradiated by a 7.3 mW He-Ne laser in the presence of crystal violet, toluidine blue O and hematoporphyrin as photosensitizers. Xylanases recovered from non-irradiated and irradiated fungi were purified and characterized. The maximum production of xylanase (42.2 U/ml) was obtained after 5 min of laser irradiation in the absence of the photosensitizer. The irradiation of the sensitized fungus diminished the production of xylanase. On purification using G-100, the specific activity of xylanase recovered from the irradiated fungus was 292 U/mg protein representing a 37-fold purification over the crude extract compared with 95.6 U/mg protein representing the 12.8-fold for the enzyme recovered from the non-irradiated fungus. The enzyme recovered from the irradiated fungus had lower molecular weight as compared with that recovered from the non-irradiated one. Characterization of the purified enzymes revealed that the enzyme recovered from the irradiated fungus was more thermostable and had a wider range of optimum reaction temperature (60-70 degrees C) and pH (4.0-12.0), compared to the non-irradiated one.