Naphthalimide Trifluoroacetyl Acetonate: A Hydrazine-Selective Chemodosimetric Sensor

The trifluoroacetyl acetonate naphthalimide derivative 1 has been synthesized in good yield. In acetonitrile solution, compound 1 reacts selectively with hydrazine (NH2NH2) to give a five-membered ring. This leads to OFF-ON fluorescence with a maximum intensity at 501 nm as well as easily discernible color changes. Based on a readily discernible and reproducible 3.9% change in overall fluorescence intensity, the limit of detection for 1 is 3.2 ppb (0.1 mu M), which is below the accepted limit for hydrazine set by the U.S. Environmental Protection Agency (EPA). Compound 1 is selective for hydrazine over other amines, including NH4OH, NH2OH, ethylenediamine, methylamine, n-butylamine, piperazine, dimethylamine, triethylamine, pyridine, and is not perturbed by environmentally abundant metal ions. When supported on glass-backed silica gel TLC plates, compound 1 acts as a fluorimetric and colorimetric probe for hydrazine vapor at a partial pressure of 9.0 mm Hg, with selectivity over other potentially interfering volatile analytes, including ammonia, methylamine, n-butylamine, formaldehyde, acetaldehyde, H2O2, HCl, and CO2 being observed. Probe 1 can also be used for the detection of hydrazine in HeLa cells and does so without appreciable interference from other biologically abundant amines and metal ions.U.S. National Science Foundation CHE-1057904Robert A. Welch Foundation F-1018CRI project grant from National Research Foundation of Korea (NRF)Korea government (MSIP) 2009-0081566Chemistr

Universal factorization property of certain polycyclic groups

AbstractLet H be a torsion-free strongly polycyclic (torsion-free virtually polycyclic, resp.) group. Let G be any group with maximal condition. We show that there exists a torsion-free strongly polycyclic (torsion-free virtually polycyclic, resp.) group G˜ and an epimorphism ε:G→G˜ such that for any homomorphism ϕ:G→H, it factors through G˜, i.e., there exists a homomorphism ϕ˜:G˜→H such that ϕ=ϕ˜∘ε. We show that this factorization property cannot be extended to any finitely generated group G. As an application of factorization, we give necessary and sufficient conditions for N(f,g)=R(f,g) to hold for maps f,g:X→Y between closed orientable n-manifolds where π1(X) has the maximal condition, Y is an infra-solvmanifold, N(f,g) and R(f,g) denote the Nielsen and Reidemeister coincidence numbers, respectively

Protein Fractions from Korean Mistletoe ( Viscum Album coloratum

Mistletoe (Viscum Album coloratum) has been known as a medicinal plant in European and Asian countries. Recent data show that biological activity of mistletoe alleviates hypertension, heart disease, renal failure, and cancer development. In this study, we report the antidiabetic effect of Korean mistletoe extract (KME). KME treatments enhanced the insulin secretion from the pancreatic β-cell without any effects of cytotoxicity. PDX-1 and beta2/neuroD known as transcription factors that regulate the expression of insulin gene were upregulated by treatment of the KME protein fractions isolated by ion-exchange chromatography after ammonium sulfate precipitation. Furthermore, these KME protein fractions significantly lowered the blood glucose level and the volume of drinking water in alloxan induced hyperglycemic mice. Taken together with the findings, it provides new insight that KME might be served as a useful source for the development of medicinal reagent to reduce blood glucose level of type I diabetic patients

A new species of torrent catfish, Liobagrus geumgangensis (Teleostei, Siluriformes, Amblycipitidae), from Korea

In a recent survey of populations of the Korean torrent catfish Liobagrus, a distinctive species was discovered from the Geum River and its tributaries flowing into the western coast of Korea, and here described as a new species, L. geumgangensis sp. nov. It is distinguishable from other congeners by a combination of the following characters: I, 8 pectoral fin-rays; 52–56 caudal-fin rays; a relatively short occiput to dorsal-fin origin distance (6.9–9.8% SL); a short pelvic-fin insertion to anal-fin origin distance (11.9–17.3% SL); a long dorsal-fin base (10.6–13.5% SL); 8–9 gill rakers; 5–8 serrations on the pectoral fin; the body and fins are dark yellow, the margins of the dorsal, anal, and caudal fins are dark brown, but the outermost rim is faintly yellow. Analysis of the cytb gene also confirmed that L. geumgangensis is a monophyletic lineage distinct from other congeners

Experimental study on the removal of sulfur compounds and siloxanes from biogas

Biogas is a renewable energy source, which can be produced by anaerobic digestion with anaerobic organisms from agriculture waste, manure, municipal waste, sewage, food waste, etc. The biogas consists primarily of methane and carbon dioxide, but also smaller amounts of nitrogen, oxygen, hydrogen and volatile organic compounds including sulfur compounds, halogenated compounds and organic silicon compounds may be present. Here, methane which is the main component in the biogas may be used as a fuel in many applications such as heating, combined heat and power systems, fuel cells, etc. For the implementation of methane, therefore, the biogas needs purification to improve its quality in most cases by removing impurities from the biogas, resulting in no corrosion and scaling problems in the applications. In the present work, a hybrid biogas purification process, consisting of a physicochemical process with an adsorption for the removal of sulfur compounds and siloxanes and a membrane separation process for the removal of carbon dioxide, has been proposed. The main focus of this study is to examine the physical properties and adsorption characteristics of adsorbents being used to remove sulfur compounds and siloxanes from the biogas. Indeed, recent studies are on the desulfurization and siloxane removal process using an activated carbon and impregnated activated carbon. However, there are many different types of sulfur compounds and siloxanes in the biogas and each may have a different reaction rate and adsorption capacity. In this study, therefore, several commercially-available adsorbents are selected to analyze their removal capacities for the main components (methane) and major impurities in the biogas. The main impurities considered in this work are hydrogen sulfide (H2S), carbonyl sulfide (COS), carbon disulfide (CS2), Octamethylcyclotetrasiloxane (D4) and Decamethylcyclopentasiloxane (D5), based on the measurements from the on-site sewage treatment plant in Incheon, Korea. In the bench-scale adsorption experiments, iron oxide, activated carbon, impregnated activated carbon and inorganic adsorbents such as zeolite and silica gel are used as adsorbents for the removal of impurities from synthetic biogas and their physical properties are analyzed with XRF, SEM and BET analyses. The experimental results show that the adsorption capacity of hydrogen sulfide in the iron oxide (IO) is superior to those of the activated carbon (AC) and impregnated activated carbon (IAC) with a relatively good adsorption capacity (Figure 1). In addition, the removal efficiency of carbonyl sulfide and carbon disulfide with the activated carbon is more effective than using the iron oxide having a very poor adsorption capacity (Figure 2). It is also shown that both activated carbon and zeolite exhibit a high adsorption capacity of siloxanes D4 and D5. Especially, in case of siloxane D5, the zeolite has a better adsorption capacity than the activated carbon (Figure 3). More detailed results will be presented at the conference. Please click Additional Files below to see the full abstract

Characteristic Plain Radiographic and Intravenous Urographic Findings of Bladder Calculi Formed over a Hair Nidus: A Case Report

We present the characteristic plain radiographic and intravenous urographic (IVU) findings of calculus formed over a hair. A 66-year-old man who had been quadriplegic for 40 years because of vertebral injury was admitted for further evaluation of frequent urinary tract infection. Plain radiography showed a linear, serpiginous calcification in the lower abdomen, and IVU revealed a round filling defect with linear radiopacity in the bladder, suggesting calculus. The gross appearance of the stone after extraction demonstrated that calcification had formed over a hair