[en] To solve the multicollinearity issue and unequal contribution of vascular parameters for the quantification of angiogenesis, we developed a quantification evaluation method of vascular parameters for angiogenesis based on in vivo micro-CT imaging of hindlimb ischemic model mice. Taking vascular volume as the ground truth parameter, nine vascular parameters were first assembled into sparse principal components (PCs) to reduce the multicolinearity issue. Aggregated boosted trees (ABTs) were then employed to analyze the importance of vascular parameters for the quantification of angiogenesis via the loadings of sparse PCs. The results demonstrated that vascular volume was mainly characterized by vascular area, vascular junction, connectivity density, segment number and vascular length, which indicated they were the key vascular parameters for the quantification of angiogenesis. The proposed quantitative evaluation method was compared with both the ABTs directly using the nine vascular parameters and Pearson correlation, which were consistent. In contrast to the ABTs directly using the vascular parameters, the proposed method can select all the key vascular parameters simultaneously, because all the key vascular parameters were assembled into the sparse PCs with the highest relative importance. (paper)

[en] A wavelength tuning experiment of a continuous-wave Ho,Pr:LiLuF₄ bulk laser operating at 2900 nm has been demonstrated for the first time. Two wavelength-tunable bands in the ranges of 2830–2902 nm and 2945–2956 nm were obtained. In addition, by using a semiconductor saturable absorber mirror, a high-peak-power passively Q-switched operation was realized. The shortest pulse width was 395 ns with a repetition rate of 7.29 kHz, corresponding to a peak power of 51.1 W. The results indicate the potential of Ho,Pr:LLF crystals for continuous-wave-tunable and passively Q-switched lasers operating at ∼3.0 µm. (letter)

[en] To compare hydrocolonic sonography with histopathology for diagnosing children with symptoms highly suggestive of Hirschsprung disease (HD). In this prospective study, patients presenting refractory constipation highly suggestive of HD underwent hydrocolonic sonography with retrograde infusion of saline into the colon. The dilated segments, narrowed segments, luminal diameter ratio, transition zone (TZ), thickening, and blood perfusion of the upstream bowel were evaluated. The sensitivity and specificity of combined and single parameters were determined in comparison with biopsy. One hundred and three children were included in this study; 49 were confirmed to have HD. The luminal diameter ratio showed superiority over other parameters. An area under the curve (AUC) of 0.969 (95% confidence interval [CI]: 0.936-1.000) and a cutoff value of 1.51 were established by receiver operating characteristic (ROC) curve analysis of the luminal diameter ratio (sensitivity: 89.8%; specificity: 96.3%). By combining the luminal diameter ratio as the major criterion with two minor criteria, hydrocolonic sonography showed the same sensitivity (91.8%) and better specificity (96.3% vs 87%) than contrast enema, but this difference was not statistically significant (p = 0.063). Consistency analysis showed a kappa value of 0.825 (p < 0.001), indicating excellent agreement between hydrocolonic sonography and contrast enema. Hydrocolonic sonography is a valuable diagnostic tool with both high sensitivity and specificity for HD diagnosis, allowing morphological and vascular assessments of the colon, and correlates well with contrast enema. In the appropriate setting, hydrocolonic sonography may be an alternative screening method for HD in a large group of children with constipation. Key Points Hydrocolonic sonography is a simple, well-tolerated diagnostic tool with both high sensitivity and specificity for HD diagnosis. Hydrocolonic sonography allows morphological and vascular assessments of the colon, and correlates well with contrast enema. Hydrocolonic sonography is a possible alternative modality for paediatric patients highly suggestive of HD.

[en] This study reports 0.83Pb(Zr_1/2Ti_1/2)O₃–0.11Pb(Zn_1/3Nb_2/3)O₃–0.06Pb(Ni_1/3Nb_2/3)O₃ (PZNNT) ceramics doped with MnO₂ were obtained through the conventional solid-state reaction method. The effects of MnO₂ additive with different phases (β-, γ-, and ε-) on the microstructure and piezoelectric properties of PZNNT ceramics were discussed under the same condition. On the basis of X-ray photoelectron spectroscopy (XPS), the results clearly showed that Mn ions in different crystal forms of MnO₂ could convert from Mn⁴⁺ ions to diverse valence states (Mn²⁺, Mn³⁺) and produce different oxygen vacancies. Furthermore, the relevant electric properties of samples increased as follows: PZNNT/β-MnO₂ < PZNNT/ε-MnO₂ < PZNNT/γ-MnO₂. The optimal electric properties could be obtained by adding 1.5 mol% γ-MnO₂, the energy conversion factor (d₃₃ × g₃₃), the mechanical quality factor (Q_m), the electromechanical coupling factor (k_p), and the Curie temperature (T_c) which were 9859 × 10⁻¹⁵ m²/N, 357, 0.556, and 315 °C, respectively. It indicates that γ-MnO₂-modified PZNNT ceramics are potential candidate materials for piezoelectric energy harvesting.