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A promising route to solve the CO2 issue is its photocatalytic back-conversion to H-based solar fuels/chemicals, particularly methanol – being widely used as a strategic material in chemical/energy-related industries. Herein, the authors address this globally interesting problem and demonstrate how through an effortless hydrothermal route and using earth-abundant elements, two efficient carbon nanotube (CNT)-based heterojunction photocatalyst/solar-energy materials, viz. CNT/NiO and CNT/NiO/Fe2O3 are synthesized and employed for methanol production. The investigations revealed that both binary and ternary composites could selectively (≥93%) produce methanol using CO2 feed in aqueous medium. Moreover, a higher performance (energy efficiency: 1.81%) was witnessed for the ternary photocatalyst. From a catalytic standpoint, the superior activity of the CNT/NiO/Fe2O3 photocatalyst was discussed in detail in terms of its larger surface area, higher absorption of incident light, better charge separation/transfer, and generation of greater photo-voltage/current to effectually split the water medium and achieve the photoconversion process. A mechanistic scheme was finally proposed for the production of methanol and methane, as liquid and gas phase products, respectively.

CNT-based nanocomposite photocatalyst/solar-energy materials serving as in situ hydrogen generators for selective conversion [hydrogenation] of CO2 into methanol: a mechanistic/photoelectrochemical outlook.  相似文献   
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Introduction

This study seeks to compare two treatment methods of lateral epicondylitis: corticosteroid injection (CSI) and a local anesthetic injection (LAI).

Materials and methods

In this single-blinded randomized clinical trial, 138 patients with the diagnosis of lateral epicondylitis were assigned either into CSI group receiving methylprednisolone 1 ml (49 patients) or LAI group (51 patients) receiving procaine 1 ml 2 % in a single dose at the maximal point tenderness site. The primary outcome measure was elbow disability using Quick DASH, and secondary outcome measures were pain intensity using Visual Analogue Scale (VAS) and recurrence rate at pretreatment visit and at 3-, 6- and 12-week post-treatment visits.

Results

There were no significant differences between the patients in both groups for demographic factors including age, gender, dominant hand, involved hand, and work pressure. Before treatment, the patients in both groups were suffering from the same rates of elbow disability and pain as measured by Quick DASH and VAS, respectively, (p > 0.05). In general, the recovery rate (comparison between pretreatment visit and last post-treatment visit) was significantly more effective and higher in CSI than LAI. CSI was dramatically more effective at 3-week visit, but less and less effective at 6- and 12-week visits. At 12-week visit the recurrence rate was 34.7 % (17 patients) in CSI group.

Conclusion

For lateral epicondylitis, CSI has the best short-term treatment results yet the highest recurrent rates. The combination of CSI with other treatment option or with a change in injection technique from single injection to peppering injection may be promising.  相似文献   
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International Journal of Mental Health and Addiction -  相似文献   
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Background:

Hypospadias is one of the most common congenital genital anomalies in males that necessitates to be operated early in infancy (when 6 to 9 months old). On the other hand, hypospadias is a challenging field of pediatric urology with multiple reconstruction techniques. A perfect hypospadias repair is supposed to return urethral continuity with sufficient caliber, eradicate phallus curvature, and supply an acceptable appearance with low complications.

Objectives:

This study aimed to evaluate the outcomes of using onlay island flap technique in the repair of hypospadias with shallow urethral plate.

Patients and Methods:

In this prospective study within June 2012 to December 2013, we performed onlay island flap procedure to repair hypospadias with shallow urethral plate measuring less than 6 millimeter. This technique was selected for all types of hypospadiasis except subcoronal type. Nesbit’s dorsal plication procedure was established for chordee. In cases with very small glans, urethroplasty was performed without glansplasty.

Results:

Twenty three patients with mean age of 30 (range 10 - 60) months underwent onlay island flap repair; all had a shallow urethral plate < 6 mm, 3 had a very small glans, and 18 had chordee. Meatus was located in distal shaft in 5 cases, mid shaft in 8, proximal in 6 and penoscrotal type in 4 patients. Chordee was corrected with Nesbit’s dorsal plication in 16 cases. Complications were: meatal stenosis in 2 cases and urethrocutaneous fistula in 2 patients, all of which were repaired surgically. Mean follow up time was 13 (3 - 20) months. All cases that had glansplasty have excellent esthetic appearance.

Conclusions:

This technique offers acceptable results regarding meatal stenosis, urethrocutaneous fistula and esthetic outcome.  相似文献   
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