<p>Ammonium nitrate (NH<sub>4</sub>NO<sub>3</sub>) is the main driver of high PM<sub>2.5</sub> episodes in Seoul, but its formation processes are not fully understood yet. Intensive experiments were conducted at the Korea University campus in Seoul during June ~ August 2018 and April ~ June 2019, when the chemical composition of PM<sub>2.5</sub> including Na<sup>+</sup>, SO<sub>4</sub><sup>2-</sup>, NH<sub>3</sub>, NO<sub>3</sub><sup>-</sup>, Cl<sup>-</sup>, Ca<sup>2+</sup>, K<sup>+</sup>, Mg<sup>2+</sup>, OC and EC, and its gaseous precursors including NO<sub>X</sub>, HNO<sub>3</sub> and SO<sub>2</sub> were continuously measured. The concentrations of PM<sub>2.5</sub> and its major constituents were noticeably higher in pre-monsoon (June) than summer monsoon (July~August) period. In particular, nitrate concentration was much higher (6.9 μg/m<sup>3</sup>) during the high PM<sub>2.5</sub> episode (24-hr average PM<sub>2.5</sub> > 35 μg/m<sup>3</sup>) in June compared to those of non-episode (3.1 μg/m<sup>3</sup>) and the other two months (0.74 μg/m<sup>3</sup>). Aerosol liquid water content (ALWC) was calculated using ISORROPIA II model, ALWC was higher during the episode than non-episode and the highest ALWC was found concurrently with the highest NO<sub>3</sub><sup>-</sup> concentration (18.2 μg/m<sup>3</sup>) at night. Concurrent increases of nitrate and ALWC cause aqueous-phase formation and hygroscopic growth of aerosol, which lead to high PM<sub>2.5</sub> concentration. In addition, ALWC was more rapidly increased with the number of accumulation mode particles larger than 100 nm in diameter at higher RH and nitrate concentration. In this study, PM<sub>2.5</sub> mass and nitrate were elevated after the NO<sub>X</sub> peak in the morning as well as at dawn. The surface of pre-existing particles was found to be prerequisite for nitrate driven PM<sub>2.5</sub> episode.</p>

BackgroundRehabilitation of normal function and form is essential in cleft lip repair. In 2005, Dr. David M. Fisher introduced an innovative method, named “an anatomical subunit approximation technique” in unilateral cleft lip repair. According to this method, circumferential incision along the columella on cleft side of the medial flap is continued to the planned top of the Cupid’s bow in straight manner, which runs parallel to the unaffected philtral ridge. Usually, small inlet incision is needed to lengthen the medial flap. On lateral flap, small triangle just above the cutaneous roll is used to prevent unesthetic shortening of upper lip. This allows better continuity of the Cupid’s bow and ideal distribution of tension.Case presentationAs a modification to original method, orbicularis oris muscle overlapping suture is applied to make the elevated philtral ridge. Concomitant primary rhinoplasty also results in good esthetic outcome with symmetric nostrils and correction of alar web. As satisfactory results were obtained in three incomplete and one complete unilateral cleft lip patients, indicating Fisher’s method can be useful in cleft lip surgery with functional and esthetic outcome.ConclusionsClinically applied Fisher’s method in unilateral cleft lip patients proved the effectiveness in improving the esthetic results with good symmetry. This method also applied with primary rhinoplasty.

No abstract

In prolonged chronic osteomyelitis, chronic inflammation and low-grade infections can result in new periosteal bone formation. Chronic osteomyelitis with proliferative periostitis (traditionally termed Garré's sclerosing osteomyelitis) mainly affects children and young adults. Here, we present two rare cases of an 11-year-old and a 12-year-old patient with suppurative chronic osteomyelitis with proliferative periostitis without any definitive infection source, such as dental caries or periodontitis. The source of infection was likely to be related to the development of a lower right third molar germ with follicular space widening. Management involved antibiotics and the removal of the third molar germ and surgical debridement. Disease remission and a normal appearance was observed at the six-month follow-up visit.

No abstract