Accurate Estimation of Discharge Hydrograph in a Compound Meandering Channel Using a Two-Dimensional Numerical Model

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Pain and removal force associated with bracket debonding: a clinical study

Objective: Pain is a problem during bracket removal, and more comfortable treatment is needed. This study examined the association of pain with the removal force required for ceramic brackets, compared with metal and plastic brackets, to determine which removal method resulted in less pain and discomfort. Methodology: 81 subjects (mean age, 25.1 years; 25 males and 56 females) were enrolled, from whom 1,235 brackets (407 ceramic, 432 plastic, and 396 metal) were removed. Measured teeth were distinguished at six segments. Pain was measured with a visual analogue scale (VAS) during the removal of each bracket. An additional grip was placed on the grips of debonding pliers with right-angled beaks; a mini loading cell sensor pinched by the grips was used to measure removal force during debonding. VAS and force values were statistically analyzed. The Kruskal–Wallis test followed by the Mann–Whitney U test with Bonferroni correction were performed for multiple comparisons; multiple regression analysis was also performed. Results: Forces in the upper and lower anterior segments were significantly smaller (p<0.05) than those in the other segments. Pain tended to be greater in the upper and lower anterior segments than in the posterior segments. In all segments, the removal force was greater for metal brackets than for plastic or ceramic brackets. Ceramic brackets caused significantly greater pain than plastic brackets for the upper and lower anterior segments. Debonding force was involved in the brackets, following adjustments for pain, upper left segment, age, and sex. Conclusions: Pain and discomfort are likely to occur during bracket debonding

Thin ZIF-8 nanosheets synthesized in hydrophilic TRAPs

The preparation method of nanosheets using hyperswollen lyotropic lamellar phases, the ‘two-dimensional reactor in amphiphilic phases (TRAP) method’, has successfully provided nanosheets of various non-layered materials. Previously reported examples started from a single hydrophobic or hydrophilic precursor and multiple hydrophobic precursors. Here, we propose a synthesis method of nanosheets of ZIF-8, zinc 2-methylimidazolate, with a sodalite-like framework. They grow up to a few nanometers of thickness and several hundred nanometers of width with neither aggregation nor impurities from multiple hydrophilic precursors in the stoichiometric ratio inside the hydrophilic TRAPs consisting of the amphiphile Brij L4. The thin nanosheets of ZIF-8 doped with Co2+(Co-ZIF-8) synthesized by the same method maintained a high specific surface area after calcination. Therefore, the oxygen reduction reaction (ORR) activity of the calcined Co-ZIF-8 NSs for fuel cells becomes higher than that of the calcined conventional Co-ZIF-8 crystals.Sasaki K., Okue T., Shu Y., et al. Thin ZIF-8 nanosheets synthesized in hydrophilic TRAPs. Dalton Transactions 50, 10394 (2021); https://doi.org/10.1039/d1dt01507a

The evaluation of asymptomatic arterial occlusive disease of the legs using an exercise test.

The Doppler-derived ankle pressure index (API) is a useful indicator of the necessity for peripheral vascular reconstruction of the lower extremities. But the API at rest dose not reflect the functional capacity of leg circulation, especially in the early stage of disease. Therefore, an asymptomatic but hemodynamically significant lesion in one leg is sometimes missed by pressure measurement at rest when there is a severe lesion with symptoms in the other leg. In this study, the API not only at rest but also after exercise was measured in twenty normal subjects and thirty-two patients with angiographically proven arteriosclerosis obliterans. About 60% of the patients had unilateral symptoms, although they had significant disease bilaterally. The API after exercise proved to be more sensitive than the API at rest and may be useful in assessing asymptomatic legs of such patients and determining their surgical indication.</p