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[Display omitted] • Synthesis of Imi-alkanolamine DES to chemically absorb SO 2 at low concentration. • Improvement of thermal stability due to hydrogen bond based on DES formation. • Outstanding absorption capacity compared with other DESs in previous literatures. • Mechanism analysis and demonstration of multi-site absorption via 1H NMR. • The proposed DESs can be a candidate for alternative technology of FGD. SO 2 generated by manufacturing facilities, power plants, and ships must be removed because it adversely affects human health even at low concentrations. Flue gas desulfurization (FGD), which is a conventional method for removing SO 2 , causes additional environmental issues, including non-recyclable reactants and wastewater. In this study, deep eutectic solvents (DESs) functionalized to absorb SO 2 at low concentrations are developed as alternatives for FGD. The physical properties, including thermal stability, of the prepared DESs were analyzed, and an enhancement in thermal stability, attributed to DES formation, was verified. Additionally, absorption capacities and reusability under 500 ppm SO 2 were analyzed through experiments involving the absorption, desorption, and reabsorption cycles. The thermal stabilities of the as-prepared DESs significantly improved compared to those of the precursors. In addition, the prepared absorbents exhibited remarkable SO 2 absorption performance owing to multi-site absorption, with values of 0.992, 0.684, and 0.628 g SO 2 /g absorbent, which are more than twice higher than those reported in previous studies. Finally, the absorption mechanism was confirmed using 1H nuclear magnetic resonance and Fourier Transform Infrared spectroscopy. Owing to the exceptional performance of the proposed absorbents, this study is expected to make a significant contribution to the alternative technology research on SO 2 separation. [ABSTRACT FROM AUTHOR]

HOSO[sub 2] radical is the key intermediate for the oxidation SO[sub 2] to SO[sub 3] by OH radical in the atmosphere. The structural aspects and the energetics of the reaction HOSO[sub 2]+O[sub 2]→SO[sub 3]+HO[sub 2] have been studied using Mo\ller-Plesset (MP2) and density functional (DFT) techniques with 6-31G[sup **] and triple-ζ, quadruple-ζ, and quintuple-ζ quality basis sets including diffuse basis functions. The detailed theoretical analyses have further revealed that this reaction could proceed through the formation of intermediate complexes and an intramolecular proton transfer like transition state. The energetics of these intermediate reactions has been studied in detail. The use of MP2 methods to study such radical mechanisms had some characteristic symmetry-breaking problem with larger basis sets. This unphysical situation with larger basis set MP2 calculations in this hypervalent system has been explained through the interpretation of the relevant energy surface. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Purpose: Currently, there is no clear evidence to support any specific treatment as a principal therapy for stage IV gastric cancer outlet obstruction (GCOO) patients. This study evaluated the outcomes of palliative gastrectomies and survival prognostic factors in patients with stage IV resectable GCOO., Materials and Methods: We retrospectively reviewed the medical records of 48 stage IV GCOO patients who underwent palliative gastrectomies between June 2010 and December 2019. Palliative gastrectomies were performed only in patients with resectable disease. Early surgical outcomes and prognostic factors were analyzed using univariate and multivariate analyses., Results: There were no specific risk factors for postoperative complications, except for being underweight. Severe postoperative complications developed in five patients, and most of the patients underwent interventional procedures and received broad-spectrum antibiotics for intra-abdominal abscesses. The multivariate survival analysis showed that palliative chemotherapy is a positive prognostic factor, while the specific type of hematogenous and lymphatic metastasis is a negative prognostic factor., Conclusions: We recommend that the treatment method for stage IV GCOO should be selected according to each patient's physical condition and tumor characteristics. In addition, we suggest that palliative gastrectomies can be performed in stage IV resectable GCOO patients without unfavorable prognostic factors (types of hematogenous and lymphatic metastases)., Competing Interests: Conflict of Interest: No potential conflict of interest relevant to this article was reported., (Copyright © 2020. Korean Gastric Cancer Association.)

Background : Among childhood illnesses requiring surgery, inguinal hernia is the most common entity. Pediatric inguinal hernia has been traditionally operated through a small incision in the inguinal region. Contralateral metachronous inguinal hernia has been the topic of discussion in pediatric surgeon's domain for a long time. Many studies have been conducted to prevent it from occurring. Although patency of processus vaginalis is known to be the cause of metachronous inguinal hernia, it is difficult to know the status of contralateral processus vaginalis preoperatively when the patient is non-symptomatic. Recently, the introduction of laparoscopic surgery has facilitated the observation and surgery of contralateral inguinal hernia during scheduled surgery of unilateral hernia repair while the processus vaginalis is intact. The standard treatment for inguinal hernia is herniotomy. Laparoscopic inguinal hernia repair has not been widely applied in Korea. The objective of this study was to analyze the accuracy of preoperative sonography results of inguinal lesion on the contralateral side in patients that needed laparoscopic operation of inguinal hernia. Methods : Data of 107 patients who received laparoscopic inguinal hernia repair and evaluation by preoperative ultrasonography at Dongguk University Ilsan Hospital from 2011 to 2015 were analyzed. Results : Preoperative sonography for inguinal lesion had a sensitivity of 20.5%, a specificity of 95.2%, a positive predictive value of 75%, and a negative predictive value of 63.2%. Its accuracy was 64.5%. A total of 107 patients had no inguinal hernia recurrence or metachronous contralateral inguinal hernia. Conclusion : Ultrasonography performed prior to traditional pediatric herniotomy is not enough for accurate diagnosis of patency of processus vaginalis in our retrospective study. Multicenter prospective study is needed to estimate accuracy of sonographic diagnosis for patency of processus vaginalis., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

Congener specific polychlorinated biphenyl (PCB) data from the stack gas of nine Korean municipal waste incinerators was used to determine characteristic congener patterns of emitted PCBs. Principal component analysis revealed three classes of incinerators according to their pattern of PCB congener emissions: those resembling the background sampling material; those producing large quantities of a few tetra-chlorinated congeners; those producing large proportions of mono (MO-) and non-ortho (NO-) congeners relative to di-ortho (DO-) levels. Also, correlations between individual PCB congeners and polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) were discovered for several NO-PCBs and tetra and penta chlorinated PCDFs. Full PCB congener data is presented along with operating conditions for each incinerator.

As the result of a fecal examination performed in October 1978 on 320 middle and high school students of Hapcheon, Korea, we found 2 cases of Rhabditis nematodes in 16-year old high school girls. Rhabditis nematodes isolated from their feces were cultured at 30 degrees C by a filter paper culture method. After careful observation of male and female adults, we confirmed them as Rhabditis elongata Schneider, 1866 on the morphological basis of the male genitalia, and the papillae and measurements of various parts of the worm bodies.