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The objective of this study was to shed light on structural features which underlay intensity of long wave absorbance of natural organic matter (NOM) using 1H NMR spectroscopy. For this purpose, a set of the NOM samples was assembled from arctic and nonarctic sampling sites (the Kolyma river basin and Moscow region, respectively). It was to ensure a substantial difference in the humification degree of the isolated organic matter-the biogeochemical proxy of the long-wave absorbance of NOM. The assembled NOM set was analyzed using solution-state 1H NMR spectroscopy. The distribution of both backbone and exchangeable protons was determined using acquisition of spectra in three different solvents. The substantially higher contribution of nonfunctionalized aliphatic moieties CHn (e.g., materials derived from linear terpenoids, MDLT) in the arctic NOM samples was revealed as compared to the nonarctic ones. The latter were characterized with the higher content of CHα protons adjacent to electron-withdrawing groups which belong to carboxyl rich alicyclic moieties (CRAMs) or to aromatic constituents of NOM. We have calculated a ratio of CHn to CHα protons as a structural descriptor which showed significant inverse correlation to intensity of long wave absorbance assessed with a use of E4/ E6 ratio and the slope of absorption spectrum. The steric hindrance of aromatic chromophoric groups of the NOM ensemble by bulky nonfunctionalized aliphatic moieties (e.g., MDLT) was set as a hypothesis for explanation of this phenomenon. The bulky aliphatics might increase a distance between the interacting groups resulting in inhibition of electronic (e.g., charge-transfer) interactions in the NOM ensemble. The obtained relationships were further explored using Fourier transform mass spectrometry as complementary technique to 1H NMR spectroscopy. The data obtained on correlation of molecular composition of NOM with 1H NMR data and optical properties were very supportive of our hypothesis that capabilities of NOM ensemble of charge transfer interactions can be dependent on structural arrangement and relative abundance of nonabsorbing aliphatic moieties.
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Compuestos Orgánicos , Ríos , Regiones Árticas , Espectroscopía de Resonancia Magnética , ProtonesRESUMEN
The abyssal ocean is broadly characterized by northward flow of the densest waters and southward flow of less-dense waters above them. Understanding what controls the strength and structure of these interhemispheric flows-referred to as the abyssal overturning circulation-is key to quantifying the ocean's ability to store carbon and heat on timescales exceeding a century. Here we show that, north of 32° S, the depth distribution of the seafloor compels dense southern-origin waters to flow northward below a depth of about 4 kilometres and to return southward predominantly at depths greater than 2.5 kilometres. Unless ventilated from the north, the overlying mid-depths (1 to 2.5 kilometres deep) host comparatively weak mean meridional flow. Backed by analysis of historical radiocarbon measurements, the findings imply that the geometry of the Pacific, Indian and Atlantic basins places a major external constraint on the overturning structure.
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AIMS/HYPOTHESIS: The adiponectin signalling pathway is largely unknown, but recently the adaptor protein containing pleckstrin homology domain, phosphotyrosine binding domain and leucine zipper motif (APPL1), has been shown to interact directly with adiponectin receptor (ADIPOR)1. APPL1 is present in C2C12 myoblasts and mouse skeletal muscle, but its presence in human skeletal muscle has not been investigated. METHODS: Samples from type 2 diabetic, and lean and non-diabetic obese participants were analysed by: immunoprecipitation and western blot; HPLC-electrospray ionisation (ESI)-mass spectrometry (MS) analysis; peak area analysis by MS; HPLC-ESI-MS/MS/MS analysis; and RT-PCR analysis of APPL1 mRNA. RESULTS: Immunoprecipitation and western blot indicated a band specific to APPL1. Tryptic digestion and HPLC-ESI-MS analysis of whole-muscle homogenate APPL1 unambiguously identified APPL1 with 56% sequence coverage. Peak area analysis by MS validated western blot results, showing APPL1 levels to be significantly increased in type 2 diabetic and obese as compared with lean participants. Targeted phosphopeptide analysis by HPLC-ESI-MS/MS/MS showed that APPL1 was phosphorylated specifically on Ser(401). APPL1 mRNA expression was significantly increased in obese and type 2 diabetic participants as compared with lean participants. After bariatric surgery in morbidly obese participants with subsequent weight loss, skeletal muscle APPL1 abundance was significantly reduced (p < 0.05) in association with an increase in plasma adiponectin (p < 0.01), increased levels of ADIPOR1 (p < 0.05) and increased muscle AMP-activated protein kinase (AMPK) phosphorylation (p < 0.05). CONCLUSIONS/INTERPRETATION: APPL1 abundance is significantly higher in type 2 diabetic muscle; APPL1 is phosphorylated in vivo on Ser(401). Improvements in hyperglycaemia and hypoadiponectinaemia following weight loss are associated with reduced skeletal muscle APPL1, and increased plasma adiponectin levels and muscle AMPK phosphorylation.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adiponectina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Obesidad/metabolismo , Transducción de Señal , Proteínas Adaptadoras Transductoras de Señales/genética , Adiponectina/genética , Adulto , Western Blotting , Diabetes Mellitus Tipo 2/genética , Electroforesis , Femenino , Humanos , Inmunoprecipitación , Masculino , Espectrometría de Masas , Obesidad/genética , Fosforilación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/genética , Transducción de Señal/fisiologíaRESUMEN
Stream ecologists have recently recognized that sediments below streams play an important role in lotic ecosystems. Water flows not only across the surface of stream channels, but also through sediment interstices; consequently, surface and subsurface biogeochemical processes are linked. Recent attempts to understand the influence of subsurface processes on stream ecosystems have tried to resolve the surface-subsurface hydrologic interactions, and to gain knowledge of the ecology of subsurface organisms.
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The existing liquid low level waste (LLLW) ystem of the Oak Ridge National Laboratory is used to collect, newtralize, concentrate, and store the radiactive and toxic waste from various sources and the Laboratory. The waste solutions are discharged from source facilities to individual collection tanks, transferred by underground piping to an evaporator facility for concentration, and pumped through the underground piping storage in underground tanks. The existing LLLW system was installed in the 1950s with several system additions up to the present. The worst-case accident postulated is an earthquake of sufficient magnitude to rupture tha tanks and/or piping so as to damage the containment integrity to thesurrounding soil and environment, The objective of an analysis of the system to provide a level of confidence in the seismic resistance of the LLWsystem to withstand the postulated earthquake (AU)
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Terremotos , Aguas Residuales , Eliminación de Aguas Residuales , Medición de RiesgoRESUMEN
Three vaccines, BCG Glaxo alone (vaccine A), BCG Glaxo plus 10(7) killed Mycobacterium vaccae (vaccine B), and BCG Glaxo plus 10(7) killed M. leprae (vaccine C), were given to groups of selected children. The effects of these vaccines on subsequent quadruple skin testing 1-3 years after vaccination were compared. All three vaccines equally and significantly (p less than 0.00001) increased positivity to tuberculin, but only vaccine B was found to significantly enhance development of skin-test positivity to leprosin A (p less than 0.002). The data support the evidence previously obtained in rural Iran that the combination of BCG with killed M. vaccae is likely to be a better vaccine for leprosy than is BCG alone.
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Vacuna BCG , Vacunas Bacterianas , Lepra/prevención & control , Mycobacterium leprae/inmunología , Vacunación , Adolescente , Preescolar , Humanos , India , Proyectos Piloto , Pruebas Cutáneas , Vacunas de Productos InactivadosRESUMEN
As part of the World Health Organization's international programme on the ecology of influenza, cloacal swabs were collected from 3,736 birds belonging to 67 species over a 3-year period in Western Australia for the isolation of ortho- and paramyxoviruses. A total of 24 influenza A viruses were isolated from various species of ducks, shearwaters , noddies , terns and a coot , and were subtyped as H1N9 , H3N8 , H4N4 , H4N6 , H6N2 , H6N4 , H?N2, H?N6 and H? N9 . The H? haemagglutinins did not react in tests with reference antisera. Whether they represent a novel haemagglutinin subtype or atypical members of an established subtype remains to be determined, although preliminary results indicate that they may be atypical members of the H7 subtype. The H1N9 isolate is the first reported isolate of this particular antigenic combination. A total of 17 Newcastle disease viruses was isolated from ducks, noddies , terns and a black- fronted plover : preliminary results suggest that they are avirulent for domestic chickens. This study indicates that ortho- and paramyxoviruses are present in a variety of wild birds in Australia.
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Aves/microbiología , Virus de la Influenza A/aislamiento & purificación , Virus de la Enfermedad de Newcastle/aislamiento & purificación , Animales , Animales Salvajes/microbiología , Australia , Cloaca/microbiología , Patos/microbiología , Pruebas de Inhibición de Hemaglutinación , Inmunodifusión , Virus de la Influenza A/clasificación , Virus de la Enfermedad de Newcastle/clasificación , Serotipificación , Especificidad de la EspecieAsunto(s)
Insulina/farmacología , Hígado/metabolismo , Músculos/metabolismo , Salmonidae/fisiología , Trucha/fisiología , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Bovinos , Relación Dosis-Respuesta a Droga , Metabolismo de los Lípidos , Hígado/efectos de los fármacos , Músculos/efectos de los fármacos , Proteínas/metabolismo , Especificidad de la EspecieRESUMEN
Leukocytes from two macropod marsupials, the quokka (Setonix brachyuras) and the tammar (Macropus eugenii) were separated from whole blood by dextran sedimentation and established in culture with either phytohemagglutinin-P, concanavalin A, or pokeweed mitogen. The leukocyte response to each mitogen, as measured by the incorporation of tritiated thymidine into DNA, was similar to that described in other experimental systems. These results suggest that the functional elements of the cellular immune response in marsupials may have evolved along very similar lines to those in the eutherian mammals.