Novel Fixable Instruments Used in Strabismus Surgery.

PURPOSE: To introduce the application of novel fixable instruments in strabismus surgery without surgical assistants. METHODS: Patients with strabismus requiring surgical treatment were recruited. Under general anesthesia all patients underwent surgery with the three novel kinds of fixable instruments without assistants. The operation time of each muscle was recorded separately. RESULTS: A total of 30 patients were enrolled in this study. There were 34 lateral rectus muscles, 22 medial rectus muscles, 2 superior rectus muscles, 2 inferior rectus muscles, and 14 inferior oblique muscles. The amount of recession and resection of the lateral rectus muscle was 6 to 11 and 4 to 6 mm, respectively, and the operation time of each muscle was between 8 and 12 minutes (mean ± standard deviation: 9.88 ± 1.59 minutes). The amount of recession and resection of the medial rectus muscle was 5 to 6.5 and 4 to 6 mm, respectively, and the operation time of each muscle was 7 to 14 minutes (mean ± standard deviation: 10.59 ± 2.38 minutes). Two superior rectus muscles were recessed 7 and 9 mm and the operation time was 8 and 10 minutes, respectively. Two inferior rectus muscles were recessed 4 and 5 mm and the operation time was 7 and 9 minutes, respectively. In addition, the operation time of each oblique muscle was 6 to 10 minutes (mean ± standard deviation: 8.57 ± 1.40 minutes). All patients recovered ocular alignment with no adverse reaction in eyes on the first day after surgery. CONCLUSIONS: With the assistance of the novel fixable instruments, the surgeon can easily perform routine strabismus surgeries even without surgical assistants. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XX-XX.].

Efficient NOx Reduction against Alkali Poisoning over a Self-Protection Armor by Fabricating Surface Ce2(SO4)3 Species: Comparison to Commercial Vanadia Catalysts.

Resolving severe deactivation by alkali metals for selective catalytic reduction of NOx with NH3 (NH3-SCR) is challenging. Herein, surface Ce2(SO4)3 species as a self-protection armor originally exhibited antipoisoning of potassium over ceria-based catalysts. The self-protection armor was also effective for other alkali (Na), alkali-earth (Ca), and heavy (Pb) metals, considerably resolving the deactivation of ceria-based SCR catalysts in practical applications. The catalytic activity tests indicated that the presence of ∼0.8 wt % potassium did not deactivate sulfated CeO2 catalysts, yet commercial V2O5-WO3/TiO2 catalysts almost lost the NOx conversions. Potassium preferably bonded with surface sulfates to form K2SO4 accompanied with the majority of surface Ce2(SO4)3 over sulfated CeO2 catalysts, but preferably coupled with active vanadia to generate inactive KVO3 species over V2O5-WO3/TiO2 catalysts. Such an active Ce2(SO4)3 species facilitated the adsorption and reactivity of NH3 and NOx, enabling ceria catalysts to maintain high catalytic efficiency in the presence of potassium. Conversely, the introduction of potassium into V2O5-WO3/TiO2 catalysts caused a considerable loss of surface acidity, hindering catalyst reactivity during the SCR reaction. The self-protection armor of Ce2(SO4)3 species may open a promising pathway to develop efficient ceria-based SCR catalysts with strong antipoisoning ability.

Tuning Microstructure and Mechanical Performance of a Co-Rich Transformation-Induced Plasticity High Entropy Alloy.

Multi-principal element alloys and high-entropy alloys (HEAs) are emerging metallic materials with unprecedented structures and properties for various applications. In this study, we tuned the microstructure and mechanical performance of a recently designed high-performance Co-rich TRIP-HEA via thermomechanical processing (TMP). The microstructures of the HEA after various TMP routines were characterized, and their correlation with room-temperature tensile performance was clarified. The results showed that grain refinement is an effective strategy for enhancing strength while retaining satisfactory ductility. The formation of incoherent precipitates slightly improves the strength but inevitably sacrifices the ductility, which needs to be considered for optimizing the TMPs. The room temperature tensile yield strength and ultimate tensile strength were increased from 254.6 to 641.3 MPa and from 702.5 to 968.4 MPa, respectively, but the tensile elongation retains a satisfactory value of 68.8%. We herein provide important insights into the regulation of the microstructure and mechanical properties of TRIP-HEAs.

Catalytic performance and mechanistic evaluation of sulfated CeO2 cubes for selective catalytic reduction of NOx with ammonia.

Sulfated CeO2 cubes were prepared by the impregnation of CeO2 cubes by ammonium sulfates, and further evaluated in selective catalytic reduction of NOx with ammonia (NH3-SCR). Catalytic activity tests indicated that NOx reduction conversions and N2 selectivity of sulfated CeO2 cubes could be significantly improved compared to pure CeO2 cubes. The synthesized sulfated CeO2 cubes were further characterized by atom-resolved high angle annular dark-field (HAADF) imaging, Fourier-transform infrared spectroscopy (FTIR) by pyridine adsorption, and temperature-programmed reduction by H2 (H2-TPR). The characterization results showed that sulfates were primarily dispersed through the corners, edges, and surfaces of CeO2 cubes, and did not significantly affect the crystal structures of CeO2 cubes. Sulfation treatment could create and strengthen Brønsted acid sites originated from the protons on surface sulfates, further facilitating ammonia adsorption and activation. The kinetic data indicated that the apparent reaction order of NO, O2, and NH3 was 0.95 to 1.01, -0.01 to 0.00, and -0.18 to -0.15, respectively. It could speculate that gaseous phase NO involving in NO catalytic oxidation was the rate-determining step over sulfated CeO2 cubes for NH3-SCR reaction. The presence of NH3 slightly inhibited the SCR reaction rate due to the competitive adsorption blocking NO oxidation sites.

Microstructure Refinement of a Transformation-Induced Plasticity High-Entropy Alloy.

High-entropy alloys (HEAs) have attracted extensive interest due to their unprecedented structure and mechanical performance. We recently proposed a series of novel corich twinning induced plasticity (TWIP) and transformation induced plasticity (TRIP) HEAs with superior tensile properties at room temperature; however, the hot deformation behavior has not been reported. Here, we investigated the dynamic recrystallization behavior and grain refinement of a representative TRIP-HEA, compressed at temperatures of 1123-1273 K with strain rates of 0.1-0.001 s-1. We characterized the impact of the temperature and strain rate on the grain structure evolution. A constitutive equation was constructed to reveal the correlations between the flow stress, strain rate, temperature, and strain. The apparent activation energy was estimated to be ~385.7 kJ/mol. The discontinuous dynamic recrystallization played an important role in the grain refinement, particularly at a relatively higher temperature and a lower strain rate, and the volume fraction and morphology of the recrystallized grains exhibited a strong dependency on the Zener-Hollomon parameter. The study provides guidelines for the grain refinement of HEAs through thermomechanical processing.

Accommodation changes after strabismus surgery due to anterior ciliary vessel disruption.

PURPOSE: To evaluate monocular accommodation changes after strabismus surgery with and without anterior ciliary vessel preservation. METHODS: Sixty patients with horizontal concomitant strabismus who were scheduled to undergo monocular strabismus surgeries were randomly divided into two groups: A (without anterior ciliary vessel preservation) and B (with anterior ciliary vessel preservation). Group A was further divided into groups A1 (surgical eyes without anterior ciliary vessel preservation) and A2 (corresponding nonsurgical eyes). Group B was further divided into groups B1 (surgical eyes with anterior ciliary vessel preservation) and B2 (corresponding nonsurgical eyes). Monocular accommodative amplitude (AA) and accommodative facility (AF) were evaluated before and 1 day after the surgery to assess accommodation. RESULTS: In groups A2, B1, and B2, the AA and AF values showed no significant difference preoperatively or postoperatively. However, compared with preoperative values, both the postoperative AA and AF values were significantly reduced in group A1. CONCLUSION: Strabismus surgery without anterior ciliary vessel preservation reduces monocular accommodation, whereas strabismus surgery with anterior ciliary vessel preservation protects accommodation.

Does the disruption of horizontal anterior ciliary vessels affect the blood-aqueous barrier function?

PURPOSE: To investigate the significance of the anterior ciliary vessels (ACVs) preservation during the conventional horizontal strabismus surgery. METHODS: Patients (≥ 8 years) with horizontal strabismus were randomly allocated into group 1 (with ACV preservation) and group 2 (without ACV preservation). The surgical eyes in group 1 were further divided into group A (one rectus muscle operated) and group B (two rectus muscles operated). Similarly, eyes in group 2 were divided into group C (one rectus muscle operated) and group D (two rectus muscles operated). The success rate of ACV preservation was calculated. The anterior chamber flare measurements of each eye by laser flare photometry were recorded on the day prior to and after operation. The flare values between groups and between pre- and post-operation in each group were compared by one-way analysis of variance and a paired t-test respectively. RESULTS: In groups A and B, the success rate of ACV preservation was 82% (27/33) and 70% (28/40)respectively, and the flare values between pre- and post-operation showed no significant differences(4.378 ± 1.527, 4.544 ± 1.452, P = 0.526; 4.625 ± 1.090, 4.989 ± 1.468, P = 0.101 respectively). However, the postoperative values were significantly increased in group C and group D(4.661 ± 1.031, 5.039 ± 1.310, P = 0.025; 4.933 ± 1.691, 5.502 ± 1.430, P = 0.000 respectively). The postoperative flare readings of group D were significantly higher than group B, while group A and group C had no significant variation. CONCLUSION: ACV preservation probably has clinical significance in reducing the undesirable influence on the blood-aqueous barrier.