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There is limited evidence of a natural course of an upper gastrointestinal (UGI)-subepithelial lesion (SEL) of 2 cm or less in size. This study aims to determine the natural course of UGI-SELs and find the risk factors of the endoscopic and endoscopic ultrasonography (EUS) findings associated with an increase in size. The medical records of 2539 patients with UGI-SELs between 2004 and 2016 were reviewed retrospectively. A total of 672 SELs of 2 cm or less in size were analyzed through EUS and followed up for at least 36 months. The mean follow-up duration was 68 months (range: 36–190 months), and 97 SELs (14.4%) showed an increase in size with a mean increase rate of 1.2 mm/year. Initial size (aOR 1.03, 95% confidence interval (CI) 1.01–1.06), an endoscopic finding of a hemorrhagic spot (aOR 3.13, 95% CI 1.14–8.60), and an EUS finding of a lesion in the fourth layer (aOR 1.87, 95% CI (1.21–2.88) were related to an increase in size. An endoscopic finding of translucidity (aOR 0.28, 95% CI (0.10–0.76) and an EUS finding of calcification (aOR 0.30, 95% CI 0.09–0.95) were inversely related to an increase in size. There was no death related to UGI-SELs during the follow-up. While most UGI-SELs of 2 cm or less in size showed no significant size change and favorable prognosis, an individualized follow-up strategy needs to be considered in case of the presence of hemorrhagic spots and lesions in the fourth layer.

The Joint Report on Multilateral Development Banks Climate Finance is an annual collaborative effort to publish multilateral development bank climate finance figures, together with a clear explanation of the methodologies for tracking this finance. This joint report, alongside the banks publication of climate finance statistics in their respective corporate media, is intended to track progress in relation to their climate finance targets such as those announced at COP21 and the greater ambition pledged for the post-2020 period.

The relationship between Korea and Latin American and the Caribbean has come a long way. As the two economies embraced trade with one another in the early 1990s, their connection went from being irrelevant to being a wealth machine. Bilateral trade grew at an impressive annual rate of 11.5%reaching a record high in 2021. The trade boom was followed by US$26 billion in investments by Korean firms in the region since 2000. Despite this meteoric rise, lingering trade barriers remain, and new challenges are emerging from a string of disruptive shocks to the global economyprotectionist backlashes; growing and interrelated sanitary, food, energy, and climate crises; and a fast-moving “digital transformation.” This monograph argues that, despite the challenges, both economies have a set of policies, institutions, and comparative advantages that, if reinforced and leveraged by trade and cooperation, can turn these shocks into bilateral and global opportunities for inclusive and sustainable growth.

Objectives:Adsorption characteristics in aqueous solution were investigated to effectively remove heavy metals by the crystallization of FeS and reaction kinetics were analyzed to compare with heavy metal adsorption characteristics of zeolite.Methods:The adsorption characteristics of each media were analyzed using Langmuir adsorption isotherm, and the adsorption reaction kinetics of heavy metals (Pb, Cu, Zn) on zeolite and FeS media were analyzed by a pseudo-first or pseudo-second order reaction kinetics.Results and Discussion:The maximum adsorption capacity of zeolite was highest in Pb, and the adsorption preference was in the order of Pb>Cu>Zn. In the case of FeS media, Cu was found to have a higher adsorption capacity than Pb or Zn, and the adsorption preference was observed to be Cu>Pb>Zn. It was found that the adsorption mechanism is based on chemical adsorption (chemisorption) because adsorption of each heavy metal onto zeolite or FeS media is more suitable for pseudo-second order kinetics.Conclusions:It was found that the removal of heavy metals through FeS media has a different pattern from zeolite, and when comparing the adsorption capacity of each media, it was found that FeS media is more effective for Zn or Cu except Pb.

Repeated chromatographic separations of the EtOAc fraction of Schisandra chinensis fruits on silica gel, octadecyl silica gel, and Sephadex LH-20 led to the isolation and identification of seven dibenzocyclooctadiene lignans (1–7). The NMR data reported in the literature for angeloyl gomisin H (5) were shown to be incorrect. We unambiguously identified the compounds based on detailed analysis of the 1D and 2D NMR data, especially from HMBC and NOESY experiments. In addition, MTT assays and cell viability experiments verified the cytotoxicity of the isolated dibenzocyclooctadiene lignans against the human cancer cell lines AGS, HeLa, and HT-29.

Laparoscopic total extraperitoneal peritoneal (TEP) repair has become increasingly popular since its introduction. The purpose of this study is to establish the safety and feasibility of TEP in elderly patients compared to that in younger patients. The clinical records of patients who received TEP hernia repair from August 2007 to September 2016 were reviewed. The patients were categorized into two groups: younger than 70 and 70 years or older. The patient demographics, operative time, estimated blood loss, rate of open conversion, complications, length of hospital stay, rate of readmission, rate of recurrence were compared. A total of 425 cases were documented. 317 (74.6%) patients were younger than 70 years and 108 (25.4%) were 70 years or older. The mean ages were 51.6 years in the younger group and 75.3 years in the older group. Co-morbidities (34.0% vs 72.2%, p = 0.000) and ASA score III and IV (4.1% vs. 6.5%, p value = 0.000) were more common in the elderly group. There were no significant differences between the two groups in the percentage of history of previous surgery in the lower abdominal region (23.9% vs 29.6%, p = 0.292), overall complications (7.2% vs 12.7%, p value = 0.177), and anesthesia-related complications (0% vs 1%, p value = 0.617). The operative time was similar between the two groups (54.3 vs 57.1 p = 0.220). The length of hospital stay (2.7 vs 3.0, p = 0.022) was longer in the elderly group. Laparoscopic TEP hernia repair can be performed safely in elderly patients without differences in perioperative complications and recurrence rate compared to that in a younger population despite a longer hospital stay.

Carbazoles have attracted great interest in recent years for a variety of applications in organic and medicinal chemistry as well as in materials science. In this work, an efficient method for the synthesis of carbazoles through the intramolecular C–H bond amination of N-substituted 2-amidobiaryls has been developed. Under visible light and an aerobic atmosphere, the transformation requires only catalytic amounts of Pd(OAc)2 and [Ir(dFppy)2phen]PF6 (dFppy = 2-(2,4-difluorophenyl)pyridine; phen = 1,10-phenanthroline), the latter of which is utilized in synthetic chemistry for the first time. Spectroscopic and electrochemical studies revealed that the reaction is initiated by photoinduced electron transfer from a palladacyclic intermediate, formed from the 2-amidobiaryl and PdII species, to the photoexcited Ir catalyst. This step triggers reductive elimination in a PdIII-containing palladacycle to produce the carbazole and a PdI species. The one-electron-reduced photocatalyst is reoxidized by O2 to generate...

The incorporation of a trifluoromethyl group into an existing scaffold can provide an effective strategy for designing new drugs and agrochemicals. Among the numerous approaches to trifluoromethylation, radical trifluoromethylation mediated by visible light-driven photoredox catalysis has gathered significant interest as it offers unique opportunities for circumventing the drawbacks encountered in conventional methods. A limited understanding of the mechanism and molecular parameters that control the catalytic actions has hampered the full utilization of photoredox catalysis reactions. To address this challenge, we evaluated and investigated the photoredox catalytic trifluoromethylation reaction using a series of cyclometalated Pt(II) complexes with systematically varied ligand structures. The Pt(II) complexes were capable of catalyzing the trifluoromethylation of non-prefunctionalized alkenes and heteroarenes in the presence of CF3I under visible light irradiation. The high excited-state redox potentials of the complexes permitted oxidative quenching during the cycle, whereas reductive quenching was forbidden. Spectroscopic measurements, including time-resolved photoluminescence and laser flash photolysis, were performed to identify the catalytic intermediates and directly monitor their conversions. The mechanistic studies provide compelling evidence that the catalytic cycle selects the oxidative quenching pathway. We also found that electron transfer during each step of the cycle strictly adhered to the Marcus normal region behaviors. The results are fully supported by additional experiments, including photoinduced ESR spectroscopy, spectroelectrochemical measurements, and quantum chemical calculations based on time-dependent density functional theory. Finally, quantum yields exceeding 100% strongly suggest that radical propagation significantly contributes to the catalytic trifluoromethylation reaction. These findings establish molecular strategies for designing trifluoromethyl sources and catalysts in an effort to enhance catalysis performance.

An efficient and environmentally benign method for the oxidation of aldehydes to carboxylic acids has been developed. Singlet oxygen, generated by visible light in the presence of a Ru or Ir photocatalyst, reacted with aldehydes to give the corresponding carboxylic acids in excellent yields. The reaction is highly chemo-selective, in which only an aldehyde moiety is reactive even in the presence of other photo-oxidation active sites. This method is an example of an ideal green chemical reaction in the sense that molecular oxygen and visible light are key sources for the transformation.

A method has been developed for the visible light-induced trifluoromethylation of heterocyclic compounds. A variety of electron-rich heterocycles were transformed into trifluoromethylated products by using CF 3 I as the trifluoromethyl radical source and Ru(bpy) 3 Cl 2 as the photocatalyst under mild reaction conditions. This operationally simple and eco-friendly process can introduce trifluoromethyl groups without prefunctionalization.

It is known that the velocity vector for compressible Navier-Stokes flows with non-zero boundary conditions can be decomposed into a singular part and its regular one near each non-convex vertex of bounded polygonal domains. The singular part is a multiplication of the corner singularity (of the Laplace type) and the stress intensity factor. In this paper we consider a finite element scheme approximating the regular part and the stress intensity factor, show its unique existence of the discrete solution and derive an (nearly) optimal error estimate. Some numerical examples confirming these results are given.

It is shown that the inf-sup condition, called the Babuska–Brezzi condition, is valid for certain meshdependent norms on a nonconvex polygonal domain. A bilinear form that is derived by inserting the corner singularity expansion into the Laplace equation is considered. A mesh-dependent fractional norm related to the least order of the corner singularity at a concave vertex is considered. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 24: 1253–1264, 2008

The trifluoromethyl (CF3) group is a staple synthon that can alter the physical and chemical properties of organic molecules. Despite recent advances in trifluoromethylation methods, the development of a general synthetic methodology for efficient and selective trifluoromethylation remains an ongoing challenge motivated by a steadily increasing demand from the pharmaceutical, agrochemical and materials science industries. In this article, we describe a simple, efficient and environmentally benign strategy for the hydrotrifluoromethylation of unactivated alkenes and alkynes through a radical-mediated reaction using an inorganic electride, [Ca2N](+)center dot e(-), as the electron source. In the transformation, anionic electrons are transferred from [Ca2N](+)center dot e(-) electrides to the trifluoromethylating reagent CF3I to initiate radical-mediated trifluoromethylation. The role of ethanol is pivotal in the transformation, acting as the solvent, an electron-releasing promoter and a hydrogen atom source. In addition, iodotrifluoromethylation of alkynes proceeds selectively upon the control of electride amount.

A highly efficient photolytic oxidation of aliphatic and aromatic aldehydes to the corresponding carboxylic acids is developed using molecular oxygen as oxidant and a fluorinated iridium complex as photocatalyst.

An efficient method for the generation of CF3-containing epoxides and aziridines is developed.

This radical-based trifluoromethylation of unactivated alkenes shows broad substrate scope and high E-selectivity.

Radical reactions! Efficient methods for the generation of CF3-containing epoxides and aziridines have been developed (see scheme). A variety of allylic alcohols and allylic amines were transformed into the corresponding epoxides and aziridines by using [Ru(bpy)3]Cl2 (bpy = 2,2'-bipyridine), CF3 I, and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (or N,N,N',N'-tetramethylethylenediamine, TMEDA) under visible-light irradiation.

A method for trifluoromethylation of alkenes has been developed employing visible light photoredox catalysis with CF(3)I, Ru(Phen)(3)Cl(2), and DBU. This process works especially well for terminal alkenes to give alkenyl-CF(3) products with only E-stereochemistry. The mild reaction conditions enable the trifluoromethylation of a range of alkenes that bear various functional groups.

A direct access to the target compounds without the need for prefunctionalization is achieved with a slight excess of agent (II).