Interaction of silver(I) and copper(I) with an O₂S₂-macrocycle - A comparative structural study

Kim, S.,Lee, E.,Lee, S.Y.,Lee, S.S.,Lindoy, L.F. Elsevier Sequoia [etc.] 2014 Inorganica chimica acta Vol.417 No.-

The 14-membered O<SUB>2</SUB>S<SUB>2</SUB>-macrocycle L reacts with AgPF<SUB>6</SUB> in acetonitrile/dichloromethane (1:1) to yield the cyclic, double S-Ag-S bridged complex, [Ag<SUB>2</SUB>L<SUB>2</SUB>(CH<SUB>3</SUB>CN)<SUB>4</SUB>](PF<SUB>6</SUB>)<SUB>2</SUB> (2), in which each Ag(I) is bound to two exo-oriented S donors arising from different macrocycles to form a 12-membered, di-Ag metallacycle. Two PF<SUB>6</SUB><SUP>-</SUP> ions form weak intramolecular contacts [Ag...F, 2.925(2)A] between the Ag centres in a bridging bidentate fashion. The coordination sphere of each Ag is completed by two weakly bound acetonitrile molecules. The respective macrocyclic ligands are arranged trans to the mean plane through the metallacycle. When the above synthetic procedure was repeated employing methanol/dichloromethane (1:1) as solvent, a complex of type [Ag<SUB>2</SUB>L<SUB>2</SUB>](PF<SUB>6</SUB>)<SUB>2</SUB> (3) was obtained whose structure incorporates a similar 12-membered metallacycle but with the respective macrocyclic rings now oriented towards the same side of the metallacyclic plane. The reaction of L with AgCF<SUB>3</SUB>SO<SUB>3</SUB> yields [Ag<SUB>2</SUB>L<SUB>2</SUB>(CF<SUB>3</SUB>SO<SUB>3</SUB>)<SUB>2</SUB>].2CH<SUB>3</SUB>CN (4) whose structure resembles that of [Ag<SUB>2</SUB>L<SUB>2</SUB>(CH<SUB>3</SUB>CN)<SUB>4</SUB>](PF<SUB>6</SUB>)<SUB>2</SUB> (2); each complex unit incorporates a di-Ag(I) 12-membered metallacycle, with symmetrical bridging bidentate CF<SUB>3</SUB>SO<SUB>3</SUB><SUP>-</SUP> ions weakly linking Ag centres. Long Ag1...Ag1C contacts are present between pairs of complex units. Reaction of Cu(CH<SUB>3</SUB>CN)<SUB>4</SUB>PF<SUB>6</SUB> (one equiv.) with L in methanol/dichloromethane (1:1) resulted in isolation of [CuL<SUB>2</SUB>]PF<SUB>6</SUB> (5) incorporating a distorted tetrahedral S<SUB>4</SUB>-coordination sphere, with each macrocycle binding as a bidentate ligand via its two (exo-orientated) S atoms. In contrast, reaction of [Cu(CH<SUB>3</SUB>CN)<SUB>4</SUB>]PF<SUB>6</SUB> (two equiv.) with L in either acetonitrile/dichloromethane (1:1) or methanol/dichloromethane (1:1) yielded [Cu<SUB>2</SUB>L<SUB>3</SUB>]PF<SUB>6</SUB> (6) in which the Cu(I) centres are bound exo to the macrocyclic cavity by individual S-donors from one L, with the coordination sphere of each Cu(I) completed by out-of-plane binding of the S<SUB>2</SUB>O donors from a second L. Unsymmetrical F...Cu contacts from a PF<SUB>6</SUB><SUP>-</SUP> anion weakly link the pair of Cu centres in a bridging bidentate fashion.

Migration of α-tocopherol and resveratrol from poly(L-lactic acid)/starch blends films into ethanol

Hwang, S.W.,Shim, J.K.,Selke, S.,Soto-Valdez, H.,Matuana, L.,Rubino, M.,Auras, R. Applied Science Publishers 2013 Journal of food engineering Vol.116 No.4

Poly(L-lactic acid) (PLLA)/starch blends with various concentrations of two natural antioxidants, α-tocopherol (α-TOC) and resveratrol, were fabricated by a melt blending and compression molding processes. The effects of the two antioxidants on the optical (color), thermal and mechanical properties of PLLA/starch blends with antioxidants were assessed. PLLA/starch blend films with α-TOC and resveratrol showed a yellowish color influenced by the combined effect of white starch and the brown color of the antioxidants. The glass transition and melting temperatures were significantly reduced with the addition of antioxidants while enhanced thermal stability was observed, which could be a benefit and important for processing and production. The enhanced mechanical properties could be attributed to not only a compatibilization effect based on the chemical linkage between PLLA and starch chains, but also restriction of the chain mobility by antioxidants. The release of resveratrol from PLLA and PLLA/starch blend films into ethanol followed Fickian behavior. The D values of α-TOC were in the range of 0.47-3.95x10<SUP>-11</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA films and 0.70-6.83x10<SUP>-11</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA/starch blend films at 13<SUP>o</SUP>C, 5.67-13.0x10<SUP>-11</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA films and 4.10-24.2x10<SUP>-11</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA/starch blend films at 23<SUP>o</SUP>C, and 89.0-118.0x10<SUP>-11</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA films and 123-282x10<SUP>-11</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA/starch blend films at 43<SUP>o</SUP>C. The D values of resveratrol were in the range of 0.073-0.54x10<SUP>-10</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA films and 1.42-6.93x10<SUP>-10</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA/starch blend films at 13<SUP>o</SUP>C, 0.90-3.44x10<SUP>-10</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA films and 4.16-22.3x10<SUP>-10</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA/starch blend films at 23<SUP>o</SUP>C, and 24.8-74.1x10<SUP>-10</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA films and 40.1-309x10<SUP>-10</SUP>cm<SUP>2</SUP>s<SUP>-1</SUP> for PLLA/starch blend films at 43<SUP>o</SUP>C.

Microbiological Quality of Alternative Water Sources in the Urban Environment

( J. P. S. Sidhu ),( W. Ahmed ),( L. Hodgers ),( K. Smith ),( S. Toze ) 한국물환경학회 2017 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2017 No.-

In Australia, decreasing rainfall, frequent drought and population growth in urban environments, along with an overall desire to achieve greater water sustainability, has increased the demand for alternative water sources such as stormwater, roof-harvested rainwater, and treated wastewater effluent. The potential public health risks associated with alternative water sources predominantly originate from the presence of enteric viruses, pathogenic bacteria, and protozoan parasites. Empirical data on the presence of pathogens is a prerequisite to accurately determine human health risks and the extent of treatment required prior to use for potable and nonpotable purposes. We have carried out a number of targeted studies on the microbiological quality of the roof-harvested rainwater, stormwater, and treated wastewater effluent in the Southeast Queensland (Australia). The main of aim these studies was to collect quantitative data on the presence of pathogens and make an assessment of the potential health risk associated with water reuse. A dedicated survey of the roof-harvested rainwater tanks in Brisbane has shown the presence of Campylobacter spp. (21%), Salmonella spp., (4%), and Giardia lamblia (13%). In addition, opportunistic pathogens Legionella spp. (99%) and Mycobacterium intracellulare (78%) were also detected\. The numbers of bacteria ranged up to 3.1 x 10⁶ PCR detectable units (pdu) L^-1 for Legionella spp., 9.6 X 10⁵ pdu L^-1 for P. aeruginosa, 6.8 X 10⁵ pdu L^-1 for M. intracellulare, 6.6 x 10⁵ pdu L^-1 for Acanthamoeba spp., 1.1 x 10⁵ pdu L^-1 for M. avium, and 9.8 X 10³ pdu L^-1 for L. pneumophila. The presence of potential opportunistic pathogens in tank water may present health risks if un-treated water is for potable and non-potable use in the house. Stormwater runoff from two urban catchments with different drainage area, impervious area, and land use, a potential source of pollution and population density was collected and analyzed for the presence of pathogens and fecal indicator bacteria. The mean FIB numbers in water samples collected after the storm event ranged from 10 ³ to 10⁴ L^-1 for E. coli and 10 ⁴ to 10⁵ L^-1 for Enterococcus spp. Salmonella enterica numbers varied between 10 to 2400 MPN L^-1. Human adenovirus (HAdV) numbers in the stormwater varied between 10 to 10³ pdu L^-1, human polyomavirus (HPyV) numbers varied between 1 to 10³ pdu L^-1. Torque teno virus (HTtV) numbers varied between 10 to 7.45 x 10³ pdu L^-1. Somatic coliphages (Microviridae) was also widely prevalent with numbers varying between 10 to 10³ pdu L^-1. The results of this study suggest that enteric virus and bacterial pathogens frequently occur in the stormwater runoff in significant numbers which could lead to increased human health risks. A quantitative survey HAdV, HPyV, HTtV and somatic coliphage (Microviridae) numbers in influent and effluent samples was carried out from three wastewater treatment plants (WWTP) employing an activated sludge process to produce secondary treated effluent in Brisbane. HPyV, HAdV, HTtV and Microviridae were consistently detected in the primary influent in high numbers (10⁵ to 10⁶ pdu L^-1) and secondary treated effluent (10² to 10³ pdu L^-1) across all three treatment plants. Under appropriate conditions, WWTPs with activated sludge process could be an effective treatment barrier with > 3 log10 removal of enteric. The results confirm the occurrence of enteric viruses in significant numbers in secondary treated effluent, tertiary treatment may be required prior to effluent reuse or discharged into the environmental to prevent exposure of people to health hazards.

Reduction of d-lactate content in sauerkraut using starter cultures of recombinant Leuconostoc mesenteroides expressing the ldhL gene

Jin, Q.,Li, L.,Moon, J.S.,Cho, S.K.,Kim, Y.J.,Lee, S.J.,Han, N.S. Society for Bioscience and Bioengineering, Japan ; 2016 Journal of bioscience and bioengineering Vol.121 No.5

<P>The n-form of lactate, which causes metabolic stress upon excessive dietary intake, is mainly produced by Leuconostoc sp., the predominant species in sauerkraut. To shift the metabolic flux of D-lactate from pyruvate to L-lactate, we expressed the L-lactate dehydrogenase (ldhL) gene in Leuconostoc mesenteroides ATCC 8293. The IdhL gene from Lactobacillus plantarum was introduced into L. mesenteroides using the shuttle vectors pLeuCM and pLeuCM42. To elevate the expression level of IdhL in L. mesenteroides, the nucleotides for pyruvate kinase promoter were fused to IdhL and cloned into above vectors to construct pLC18pkL and pLC42pkL. As results, introduction of pLC42pkL in L. mesenteroides significantly improved both L-LDH activity and L-lactate productivity during fermentation, decreasing the D-/L-lactate ratio. When used as a starter culture for sauerkraut fermentation, recombinant L. mesenteroides harboring pLC42pkL increased L-lactate concentration and decreased D-lactate concentration compared to the wild type strain. We newly developed a recombinant L. mesenteroides which has high L-lactate dehydrogenase activity and applied this strain to minimize the harmful effect of D-lactate during the sauerkraut fermentation. To the best of our knowledge, we demonstrate for the first time the effective use of recombinant Leuconostoc sp. for quality improvement of fermented foods. (C) 2015, The Society for Biotechnology, Japan. All rights reserved.</P>

Influence of l-Dopa adsorption time and concentration on Au nanorods aggregation for SERS quantitative analysis

Oliveira Tatiana A.,Martin Cibely S.,Rubira Rafael J.G.,de Barros Anerise,Mazali Italo O.,Constantino Carlos J.L. 한국물리학회 2023 Current Applied Physics Vol.54 No.-

Levodopa (l-Dopa) is an important neurotransmitter from the amino acid family and is also associated with the treatment of Parkinson's disease. The obtention of the l-Dopa SERS signal in colloid is a challenge due to the zwitterionic charge promoting repulsion from nanoparticle surface and leading to poor or not active SERS signal. In this work, SERS signal of l-Dopa was successfully obtained using Au nanorods (AuNRs) covered with a cationic lipid bilayer and using the 785 nm laser line. The UV–Vis extinction, dynamic light scattering, and zeta potential results indicated an influence of l-Dopa adsorption time and l-Dopa concentration on AuNRs aggregation. The SERS signal followed this time dependence, being the characteristic l-Dopa band observed only after 30 min. The l-Dopa quantitative analysis using the standard addition method presented a linear SERS signal at 439 cm−1 with a limit of detection of 6.7 × 10−7 mol L−1 for peak intensity, and 7.9 × 10−7 mol L−1 for band integrated area.

만성 임파성 백혈병 1 예 보고와 문헌 고찰

박승광 ( S. K. Park ),유수웅 ( S. W. You ),이봉재 ( B. J. Lee ),성락훈 ( L. H. Sung ) 대한내과학회 1972 대한내과학회지 Vol.15 No.2

The purpose of this report is to illustrate the long course and rarity of C.L.L. in Korea. This is the first case of C.L.L. among 107 all leukemia during the past 10 years in National Medical Center. Variation in the incidence of C.L.L. are compared to oth

Characterization of odourous compounds in air, leachate, stream and well in and around Taju-Bello Dumpsite, Lagos, Nigeria

Azeez, L.,Oyedeji, O.A.,Abdulsalami, I.O.,Adewuyi, S.O. Techno-Press 2013 Advances in environmental research Vol.2 No.2

This study investigated the concentrations of odourous compounds in air, leachate, stream and well in and around Taju-Bello dumpsite. Meteorological parameters (temperature, relative humidity, wind velocity) and six odour families comprising sulphur ($H_2S$), ammonia ($NH_3$), aromatic (benzene, toluene, ethylbenzene, styrene, p-xylene, m-xylene), aliphatic (hexane), oxygenated (formaldehyde, acetaldehyde) and halogenated (tetrachloroethene, trichloroethene, carbontetrachloride) compounds were measured. Meteorological parameters suggested low dispersal of pollutants at L1 with possible perspiration and suffocation from exposure to high temperature, relative humidity and low wind velocity. The trend of abundance of odourous compounds at studied locations is of the order dumpsite (L1) > leachate (L4) > 100 m away from dumpsite (L2) > 200 m away from dumpsite (L3) > stream (L5) > well (L6). $H_2S$, Oxygenated and aromatic compounds were the major contributors to odour strength in these locations. Correlation, factor and cluster analyses of the data revealed similarities of sources as biogenics and xenobiotics inherent in the wastes as the main sources of these odourous compounds.

Development of an experimental apparatus and protocol for determining antimicrobial activities of gaseous plant essential oils

Seo, H.S.,Beuchat, L.R.,Kim, H.,Ryu, J.H. Elsevier Science Publishers 2015 International journal of food microbiology Vol.215 No.-

There is a growing interest in the use of naturally-occurring antimicrobial agents such as plant essential oils (EOs) to inhibit the growth of hazardous and spoilage microorganisms in foods. Gaseous EOs (EO gases) have many potential applications in the food industry, including use as antimicrobial agents in food packaging materials and sanitizing agents for foods and food-contact surfaces, and in food processing environments. Despite the potentially beneficial applications of EO gases, there is no standard method to evaluate their antimicrobial activities. Thus, the present study was aimed at developing an experimental apparatus and protocol to determine the minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) of EO gases against microorganisms. A sealed experimental apparatus was constructed for simultaneous evaluation of antimicrobial activities of EO gases at different concentrations without creating concentration gradients. A differential medium was then evaluated in which a color change allowed for the determination of growth of glucose-fermenting microorganisms. Lastly, an experimental protocol for the assessment of MIC and MLC values of EO gases was developed, and these values were determined for 31 EO gases against Escherichia coli O157:H7 as a model bacterium. Results showed that cinnamon bark EO gas had the lowest MIC (0.0391μl/ml), followed by thyme-thymol EO gas (0.0781μl/ml), oregano EO gas (0.3125μl/ml), peppermint EO gas (0.6250μl/ml), and thyme-linalool EO gas (0.6250μl/ml). The order of the MLC values of the EO gases against the E. coli O157:H7 was thyme-thymol (0.0781μl/ml)<cinnamon bark (0.1563μl/ml)<oregano (0.3125μl/ml)<peppermint (0.6250μl/ml)=thyme-linalool (0.6250μl/ml). The experimental apparatus and protocol enable rapid and accurate determination of the MIC and MLC values of EO gases and perhaps other types of gaseous antimicrobial agents.

Local electronic structure of Mn dopants in ZnO probed by resonant inelastic x-ray scattering

Chang, G S,Kurmaev, E Z,Jung, S W,Kim, H-J,Yi, G-C,Lee, S-I,Yablonskikh, M V,Pedersen, T M,Moewes, A,Finkelstein, L D IOP Pub 2007 Journal of physics, an Institute of Physics journa Vol.19 No.27

<P>The electronic structure of Mn dopants in ZnO epitaxial thin films synthesized at different temperatures has been investigated using resonant inelastic x-ray scattering. The resulting Mn L<SUB>2,3</SUB> x-ray emission spectra of Zn<SUB>0.8</SUB>Mn<SUB>0.2</SUB>O (resonantly excited at L<SUB>2</SUB> and L<SUB>3</SUB> absorption edges) reveal different spectral features depending on the growth temperature of the films. The relative integral intensity ratio of Mn L<SUB>2</SUB> to Mn L<SUB>3</SUB> emission lines is greatly suppressed in the case of nonmagnetic Zn<SUB>0.8</SUB>Mn<SUB>0.2</SUB>O grown at 700 °C due to L<SUB>2</SUB>L<SUB>3</SUB>M<SUB>4,5</SUB> Coster–Kronig transitions. The ferromagnetic sample grown at 600 °C exhibits a normal oxide structure. The results suggest that a high growth temperature causes direct Mn–Mn bonds from the segregation of Mn atoms in ZnO. Therefore the disappearance of ferromagnetism in Mn-doped ZnO can be attributed to antiferromagnetic Mn–Mn exchange interactions due to the inhomogeneous local environment around the Mn impurities.</P>

A comparison of liveweight gain of lambs weaned early onto a herb-clover mixed sward and weaned conventionally onto a ryegrass-clover pasture and herb-clover mixed sward

W.E.M.L.J. Ekanayake,R.A. Corner-Thomas,L. M. Cranston,P.R. Kenyon,S.T. Morris 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.2

Objective: The aim of the present study was to identify the impact of early weaning of lambs at approximately seven weeks of age onto a herb-clover mix on the liveweight gain of lambs and their dams. Methods: In 2015, twin-born lambs that weighed a minimum of 16 kg (n = 134) were randomly allocated to one of three treatments: i) Early-weaned (58 days after the midpoint of lambing) onto an unrestricted allowance (>1,200 kg dry matter/ha) of herb-clover mix (HerbEW); ii) Lambs+dams unweaned onto an unrestricted allowance of herb-clover mix until conventional weaning (95 days after the midpoint of lambing) (HerbCW); iii) Lambs+ dams unweaned onto an unrestricted allowance of grass-clover pasture until conventional weaning (GrassCW). In 2016, twin-born lambs that weighed a minimum of 16 kg (n = 170) were randomly allocated to one of four treatments: i), ii), iii) (similar to 2015) and iv) Lambs+ dams unweaned onto a restricted allowance (<1,200 kg dry matter/ha) of grass-clover pasture until conventional weaning (93 days after the midpoint of lambing) (Restricted-GrassCW). Results: In 2015, liveweight gain from L58 to L95 of HerbCW and GrassCW lambs did not differ (p>0.05), but were greater than HerbEW lambs. In 2016, HerbCW lambs had greater (p<0.05) liveweight gains from L51 to L93 than GrassCW followed by HerbEW and Restricted-GrassCW lambs. In 2015, liveweight gain from L58 to L95 of HerbEW ewes were greater than both GrassCW and HerbCW ewes while in 2016, liveweight gain of from L51 to L93 GrassCW and HerbCW ewes did not differ (p>0.05) but were greater (p<0.05) than those of HerbEW and Restricted-GrassCW ewes. Conclusion: These results indicate that when grass-clover pasture supply can be maintained at unrestricted intake level, there may be no benefit of weaning lambs early. However, at restricted pasture conditions lambs can achieve greater liveweight gains when weaned early onto a herb-clover mix.