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Very Strong (very + strong)
Terms modified by Very Strong Selected AbstractsMolecular recognition of sugars by lanthanide (III) complexes of a conjugate of N, N -bis[2-[bis[2-(1, 1-dimethylethoxy)-2-oxoethyl]amino]ethyl]glycine and phenylboronic acidCONTRAST MEDIA & MOLECULAR IMAGING, Issue 4 2007Elisa Battistini Abstract A novel conjugate of phenylboronic acid and an Ln(DTPA) derivative, in which the central acetate pendant arm was replaced by the methylamide of L -lysine, was synthesized and characterized. The results of a fit of variable 17O NMR data and a 1H NMRD profile show that the water residence lifetime of the Gd(III) complex (150,ns) is shorter than that of the parent compound Gd(DTPA)2, (303,ns). Furthermore, the data suggest that several water molecules in the second coordination sphere of Gd(III) contribute to the relaxivity of the conjugate. The Ln(III) complexes of this conjugate are highly suitable for molecular recognition of sugars. The interaction with various sugars was investigated by 11B NMR spectroscopy. Thanks to the thiourea function that links the phenylboronic acid targeting vector with the DTPA derivative, the interactions are stronger than that of phenylboronic acid itself. In particular, the interaction with N -propylfructosamine, a model for the glucose residue in glycated human serum albumin (HSA), is very strong. Unfortunately, the complex also shows a rather strong interaction with hexose-free HSA (KA,=,705,±,300). Copyright © 2007 John Wiley & Sons, Ltd. [source] Gonadal structure of the serial-sex changing gobiid fish Trimma okinawaeDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 1 2005Yasuhisa Kobayashi In order to obtain basic information about the role played by endogenous sex hormones in bringing about sex changes in the serial-sex changing gobiid fish Trimma okinawae, the gonadal structure of male and female phases were observed histologically. Steroid-producing cells (SPC; Leydig cells in a testis) were observed ultrastructurally in the ovaries and testes of both female-phase and male-phase fish. In addition, gonadal expression of P450 cholesterol side-chain-cleavage (scc) was examined immunohistochemically. Gonads of fish in female and male phases were observed to have both ovaries and testes simultaneously. Female-phase fish had matured with many developed vitellogenic oocytes, while male-phase individuals had immature ovaries with many numbers of previtellogenic oocytes at the perinucleolus stage. Testes of fish in different sexual phases had active spermatogenic germ cells. Organellae of SPC in the ovaries of female-phase fish had active structures of steroid production. In contrast, SPC in the ovaries of male-phase fish did not show active structures of steroid production. Immunopositive reactions against the scc antibody in the ovaries of female-phase fish were very strong, but immunoreactions in the ovaries of male-phase fish were very weak. In the testis, moderate immunopositive signals were obtained from dual-phase male/females. [source] Modeling the effect of high dead-space syringes on the human immunodeficiency virus (HIV) epidemic among injecting drug usersADDICTION, Issue 8 2010Georgiy V. Bobashev ABSTRACT Aims To illustrate the impact of different proportions of injecting drug users (IDUs) sharing high dead-space syringes (HDSS) or low dead-space syringes (LDSS) on the probability of human immunodeficiency virus (HIV) transmission; and thus the impact on injection-related HIV prevalence and incidence. Design A stochastic mathematical model was used to evaluate the impact of HDSS use in high- and low-risk IDU populations. Model parameters were obtained from peer-reviewed publications. Analytical solutions of a simplified deterministic model were obtained to explain the effect of HDSS on HIV endemic states. Findings Simulation analysis shows that the HIV epidemic could be sustained even when a small percentage of sharing (10%) involved HDSS. The effect is much stronger in high-risk compared with low-risk populations. Steady state HIV prevalence increases with the proportion of HDSS, and for high- and low-risk populations reaches around 80% and 20%, respectively. For low-risk populations, the use of LDSS could result in the virtual elimination of HIV. These results are dependent upon an evidence-supported assumption of a significant difference in HIV transmission risk associated with HDSS versus LDSS. Conclusions Our models suggest that injection-related HIV epidemics may not occur when most (e.g. 95% or more) IDUs use LDSS. While these results are based on indirect risk measures and a number of simplifying assumptions, the effect of blood retained in high dead-space syringes on HIV prevalence seems to be very strong, even using relatively conservative assumptions. The findings have potential implications for needle exchange programs and the types of syringes produced and distributed world-wide. [source] Evolution in ecological field experiments: implications for effect sizeECOLOGY LETTERS, Issue 3 2008Sharon Y. Strauss Abstract Rapid evolution in response to strong selection, much of which is human-induced, has been indisputably documented. In this perspective, we suggest that adaptation may influence the effect size of treatments in ecological field experiments and alter our predictions of future dynamics in ecological systems. Field experiments often impose very strong and consistent selection over multiple generations. Focal populations may adapt to these treatments and, in the process, increase or decrease the magnitude of the treatment effect through time. We argue that how effect size changes through time will depend on the evolutionary history of the experimental population, the type of experimental manipulation, and the traits involved in adaptive responses. While no field study has conclusively demonstrated evolution in response to treatments with concomitant changes in ecological effect size, we present several examples that provide strong circumstantial evidence that such effects occur. We conclude with a consideration of the differences between plastic and genetic responses to treatments and discuss future research directions linking adaptation to ecological effect size. [source] Ruthenium-to-Platinum Interactions in ,6,,1 NCN-Pincer Arene Heterobimetallic Complexes: An Experimental and Theoretical StudyEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 29 2010Sylvestre Bonnet Abstract A series of ,6,,1 -heterobimetallic complexes have been prepared in which a [Ru(,6 -arene)(C5R5)]+ fragment (R = H or Me) and an ,1 -NCN-pincer platinum fragment are combined within the same molecule. In complexes [2]+ and [3]+, the ruthenium and platinum centers are ,6 and ,1 coordinated, respectively, to the same arene ring, whereas in [4A]+ and [5A]+ they are coordinated to two different arene rings that are linked with a covalent bond ([4A]+) or an ethyl bridge ([5A]+). Upon changing the organic manifold between both metal centers, very strong ([2]+) to very weak ([5A]+) ruthenium-to-platinum interactions are obtained. Experimentally, X-ray crystal structures show an increaing steric hindrance when the Ru,Pt distance diminishes, and electrochemical and 195Pt NMR spectroscopic studies show a decreasing electron density on platinum from [5A]+ to [2]+. Theoretical DFT calculations were undertaken, which show an increasing charge on platinum from [5A]+ to [2]+. Our theoretical analysis shows that the particularly strong ruthenium-to-platinum electronic interactions in [2]+ and [3]+ do not come from binding of ruthenium to platinum, but from the pincer Cipso sharing its electron density between both metal centers, which decreases the , donation to platinum, and from increased backdonation of the platinum d electrons into the , system of the arene ring. [source] Human salivary aggregation in Streptococcus intermedius type g strains: relationship with IgAFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2004Taihei Yamaguchi Abstract Bacterial aggregation is an important step in elimination from the human body to protect against infection. Streptococcus intermedius K1K aggregates in human saliva. In this study, the salivary agglutinin was identified. The aggregation level was very strong in sonic-treated saliva and 1-,m filtrate. Preincubation of human saliva with anti-human , chain serum or anti-human whole saliva serum completely inhibited aggregation, but preincubation with anti-human , chain serum or anti-Fc fragment of human IgG serum had no effect. Agglutinin of human saliva that could aggregate the strain K1K was purified using DEAE,Sepharose CL-6B, Phenyl,Sepharose CL-4B and Sephacryl S200HR gel filtration. Purified salivary agglutinin was characterized with electrophoresis and immunological techniques, indicating that purified material was IgA. Bacterial aggregation was dependent on the presence of calcium. Saliva filtrate specimens from eight healthy men and eight women showed different aggregation activities. Three men and one woman had little activity. These data show that the present bacterial aggregation was an immunoreaction between IgA in saliva and the bacteria dependent on the levels of calcium. In addition, the IgA in human saliva related with possible calcium-dependent antigen(s) on the surface of strain K1K. [source] Fast free surface multiples attenuation workflow for three-dimensional ocean bottom seismic dataGEOPHYSICAL PROSPECTING, Issue 5 2009Bärbel Traub ABSTRACT Water multiples can be very strong and contaminate the primary reflections. This can cause problems in the processing flow and the interpretation of the subsurface image. Hence, multiples suppression is an important part of the preprocessing flow. We present a fast workflow for attenuation of free surface related multiples for 2D and 3D ocean bottom seismic data based on the wave equation approach. Included in the workflow are: 1. Calibration of the pressure and vertical velocity components by using wavefield splitting. 2. Data interpolation by using offset projection. 3. Fast Radon transform by using fast fractional Fourier transform. Advantages of this workflow are that it is fast, efficient and the only requirements are the recording of both pressure and vertical particle components at some point below the source in the water column. [source] Four New Triterpenes from Anchusa azurea var. azureaHELVETICA CHIMICA ACTA, Issue 3 2010e Kuruüzüm-Uz Abstract Four new triterpene glycosides, named oleanazuroside 1 (1), oleanazuroside 2 (2), ursolazuroside 1 (3), and ursolazuroside 2 (4), together with the seven known compounds 5,11, were isolated from the MeOH extract of the aerial parts of Anchusa azureaMiller var. azurea. Their structures were elucidated by means of spectroscopic evidence (UV, IR, MALDI-MS, and 1D- and 2D-NMR). The radical-scavenging activities against 2,2-diphenyl-1-picrylhydrazyl (DPPH) of the BuOH extract and of 8 and 10 were very strong (Table,5). [source] Variability of southeastern Queensland rainfall and climate indicesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 6 2004Bradley F. Murphy Abstract The variability of climate indices and rainfall in southeastern (SE) Queensland (Qld) is studied. Using high-resolution gridded rainfall data for all of Australia and global sea-surface temperatures (SSTs), the relationship between Australia-wide rainfall (and in SE Qld in particular) and SST indices and the southern oscillation index (SOI) have been investigated. It is found that SE Qld is more subject to the breakdown of correlations between the SOI and rainfall than any other part of Australia. Model predictions suggest that this is probable in the future. Considering only time scales longer than interannual, it was found that SSTs in the central tropical Pacific Ocean (TPO; represented by the Niño-4 index) correlated best with SE Qld rainfall. Eastern TPO (Niño-3) SSTs and the SOI produced successively weaker correlations. The time series of the second modes of variability of SSTs over the Pacific and Indian Oceans were shown to have limited impact on SE Qld rainfall variability. The data were split into periods before and after 1946, when Australian mean rainfall changed. Whereas the SOI correlations with rainfall in SE Australia were similar in both periods, in SE Qld the correlations were very weak in the earlier period (0.06) but very strong in the later period (0.72). The Niño-4 index correlated better than the Niño-3 index in both periods, but both indexes showed smaller changes from the earlier to the later periods than the SOI. Copyright © 2004 Royal Meteorological Society. [source] Exchange rates, prices and money: A long-run perspectiveINTERNATIONAL JOURNAL OF FINANCE & ECONOMICS, Issue 4 2001Paul De Grauwe Abstract In this paper we analyse the long-run proportionality and neutrality propositions between inflation and money growth and between exchange rate changes and money growth. Using a sample of 100 countries over a thirty-year period we find that the evidence in favour of these propositions is weak for the low inflation countries and very strong for the high inflation countries. We propose an explanation based on productivity shocks and transaction costs. Copyright © 2001 John Wiley & Sons, Ltd. [source] Initial evaluation of a field-friendly extraction procedure for the enzymatic assay of cassava cyanogensINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2007Gerard M. O'Brien Summary A novel ,field friendly' extraction procedure has been developed for the enzymatic colorimetric determination of cyanogenic potential (CNP) in fresh cassava root parenchyma. The novel procedure does not require electrical power or vacuum, and employs inexpensive lightweight equipment, making it suitable for remote field sites. Testing of the procedure involved ten fresh roots (24,80 mg kg,1 total CNP, as HCN, fresh basis). From the parenchyma of each root, one extract was made using the novel procedure, and a ,control' extract was made using a traditional laboratory-based procedure. Total CNP assay of the extracts indicated strong (y = mx) or very strong (y = mx + c) correlation of results obtained using the two procedures, while a very strong correlation (y = mx) was obtained for free HCN. Based on this preliminary evidence, the novel procedure is satisfactory at least for total CNP assay of fresh low-CNP cassava roots. [source] Donor-Stabilized Phosphenium Adducts as New Efficient and Immobilizing Ligands in Palladium-Catalyzed Alkynylation and Platinum-Catalyzed Hydrogenation in Ionic LiquidsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2009Samer Saleh Abstract The straightforward synthesis of a new donor-stabilized phosphenium ligand 3d by addition of bromodifurylphosphine to 1,3-dimethylimidazolium-2-carboxylate 1 is described. The obtained ligand exhibits a very strong ,-acceptor character, comparable to that of triphenyl phosphite [P(OPh)3] or of tris-halogenophosphines, with a ,CO(A1) at 2087,cm,1 for its nickel tricarbonyl complex. This ligand, as well as the related 3a which was obtained from chlorodiphenylphosphine, were tested in palladium-catalyzed aryl alkynylation and in the platinum-catalyzed selective hydrogenation of chloronitrobenzenes, both in an ionic liquid phase. In CC bond cross-coupling we observed that the increase of the ,-acceptor character in ligand 3d, due to the introduction of an additional electron-withdrawing group, provides a very efficient catalyst in the alkynylation reaction of aryl bromides with phenylacetylene, including the deactivated 4-bromoanisole or the sterically hindered 2-bromonaphthalene. The catalytic activity decreases with recycling due to the sensitiveness of ligands to protonation in the ionic phase. Conversely, a multiple recycling of the metal/ligand system in non-acidic media was achieved from platinum-catalyzed hydrogenation of m- chloronitrobenzene. The catalytic results obtained by employing the complex of platinum(II) chloride with 3a [trans -PtCl2(3a)2] in comparison with the non-ionic related trans -tris(triphenylphosphine)platinum dichloride [trans -PtCl2(PPh3)2] complex clearly indicate that the simultaneous existence of a strong ,-acceptor character and a positive charge within the ligand 3a significantly increases the life-time of the platinum catalyst. The selectivity of the reaction is also improved by decreasing the undesirable formation of dehalogenation products. This cationic platinum complex trans -PtCl2(3a)2 is the first example of a highly selective catalyst for hydrogenation of chloronitroarenes immobilized in an ionic liquid phase. The system was recycled six times without noticeable metal leaching in the organic phase, and no loss of activity. [source] An evaluation of monitoring possibilities of argatroban using rotational thromboelastometry and activated partial thromboplastin timeACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2010M. ENGSTRÖM Background: Rotational thrombelastometry/thrombelastography with ROTEM® and TEG® is becoming available bedside in an increasing number of intensive care units, where many patients with heparin-induced thrombocytopenia (HIT) are treated. The study has been performed in an effort to find out whether ROTEM® could be an alternative to activated partial thromboplastin time (aPTT) when argatroban is used for anticoagulation. Methods: Argatroban was added in vitro to a series of citrated whole-blood samples from 10 healthy volunteers to obtain whole-blood concentrations of 0, 0.125, 0.25, 0.5, 1.0, 2.0, 4.0 and 8.0 mg/l. ROTEM® and whole-blood aPTT analyses were performed at each argatroban concentration. Correlation analyses were performed using the Spearman correlation analysis. Results: There was a significant and strong correlation between argatroban concentrations and clotting time (CT in ROTEM® analysis with INTEM) (P<0.0001 and r=0.98). Also, the ROTEM® time to maximum clot formation velocity (MAXV-t) appeared to have a very strong and highly significant correlation to argatroban concentrations (P<0.0001 and r=0.95). When we studied the correlation between aPTT and CT, we found a highly significant and strong correlation between these two analyses (P<0.0001 and r=0.97), especially so in the clinically relevant therapeutic range up to 100 s aPTT prolongation for HIT patients. Conclusion: A significant and strong correlation was found between argatroban concentrations and several ROTEM® parameters. Rotational thrombelastometry/thrombelastography has a potential role in increasing the safety of argatroban anticoagulation in critically ill patients. [source] Psychotherapy in Australia: Clinical psychology and its approach to depressionJOURNAL OF CLINICAL PSYCHOLOGY, Issue 8 2007David J. Kavanagh In Australia, clinical psychology training is dominated by cognitive and behavioral treatments (CBTs), although there is exposure to other theoretical orientations. Since 2001, over 20% of general medical practitioners (GPs) have received training in CBT, and psychiatry training increasingly incorporates CBT elements. Psychotherapy by medical practitioners is financially supported by universal health care funding with supplementation by patients and their private health insurance. Federally funded health benefits for up to 12 psychology consultations per year are provided on referral from GPs and psychiatrists, and initial takeup has been very strong. Mrs. A would be a typical patient for such a referral. However, she would not fulfill criteria for priority access from state-funded mental health services. Mrs. A would probably consult a GP and receive antidepressants, although she may also access a range of other community support programs. Access to and acceptance of psychotherapy would be greater in urban areas, and if she were of Anglo-Saxon and nonindigenous origin. © 2007 Wiley Periodicals, Inc. J Clin Psychol: In Session 63: 725,733, 2007. [source] Regulation of development of oligodendrocytesJOURNAL OF NEUROCHEMISTRY, Issue 2002K. Ikenaka Oligodendrocyte (OL) is the myelin-forming glial cell in the central nervous system. In the spinal cord, molecular markers for OL precursor cells (OPCs), such as PDGF a-receptor (PDGFR a), are first expressed in a strictly restricted focus of the ventral ventricular lumen at E12.5 in mouse and later spread throughout the cord. To investigate how they originate from these specific regions, we used an explant culture system of E12 mouse cervical spinal cord. When we cultured the ventral and dorsal spinal cords separately, a robust increase in the number of O4+ cells was observed in the ventral fragment. This phenomenon suggests the presence of factors inhibiting OL development from dorsal spinal cord. BMP4 is secreted from dorsal spinal cord and is a strong candidate for this factor; however, it did not affect OL development in our system. Here we show that Wnt-1 and Wnt-3a, in contrast, may have a role in OL maturation. The developmental profile of wnt-1/3a gene expressions in the dorsal spinal cord showed a significant correlation with that of the dorsal activity, which was very strong at E11, and then reduced to an undetectable level by E14. When Wnt-3a was added to the dissociation culture prepared from E14 mouse ventral cervical cords, the numbers of OL decreased. b-Catenin and LEF family proteins are known to form a transcription factor complex at the down stream of Wnt signalling. OL,like differentiation of CG4 cells was inhibited by constitutively active LEF-b-Catenin, supporting the idea that Wnt signalling directly inhibits OL differentiation. [source] Land use and soil erosion in the upper reaches of the Yangtze River: some socio-economic considerations on China's Grain-for-Green ProgrammeLAND DEGRADATION AND DEVELOPMENT, Issue 6 2006H. L. Long Abstract Soil erosion in the upper reaches of the Yangtze River in China is a major concern and the Central Government has initiated the Grain-for-Green Programme to convert farmland to forests and grassland to improve the environment. This paper analyses the relationship between land use and soil erosion in Zhongjiang, a typical agricultural county of Sichuan Province located in areas with severe soil erosion in the upper reaches of the Yangtze River. In our analysis, we use the ArcGIS spatial analysis module with detailed land-use data as well as data on slope conditions and soil erosion. Our research shows that the most serious soil erosion is occurring on agricultural land with a slope of 10,25 degrees. Both farmland and permanent crops are affected by soil erosion, with almost the same percentage of soil erosion for corresponding slope conditions. Farmland with soil erosion accounts for 86·2,per,cent of the total eroded agricultural land. In the farmland with soil erosion, 22·5,per,cent have a slope of,<,5 degrees, 20·3,per,cent have a slope of 5,10 degrees, and 57·1,per,cent have a slope of,>,10 degrees. On gentle slopes with less than 5 degrees inclination, some 6,per,cent of the farmland had strong (5000,8000,t,km,2,y,1) or very strong (8000,15000,t,km,2,y,1) erosion. However, on steep slopes of more than 25 degrees, strong or very strong erosion was reported for more than 42,per,cent of the farmland. These numbers explain why the task of soil and water conservation should be focused on the prevention of soil erosion on farmland with steep or very steep slopes. A Feasibility Index is developed and integrated socio-economic assessment on the feasibility of improving sloping farmland in 56 townships and towns is carried out. Finally, to ensure the success of the Grain-for-Green Programme, countermeasures to improve sloping farmland and control soil erosion are proposed according to the values of the Feasibility Index in the townships and towns. These include: (1) to terrace sloping farmland on a large scale and to convert farmland with a slope of over 25 degrees to forests or grassland; (2) to develop ecological agriculture combined with improving the sloping farmland and constructing prime farmland and to pay more attention to improving the technology for irrigation and cultivation techniques; and (3) to carry out soil conservation on steep-sloping farmland using suggested techniques. In addition, improving ecosystems and the inhabited environment through yard and garden construction for households is also an effective way to prevent soil erosion. Copyright © 2006 John Wiley & Sons, Ltd. [source] Is the Acquisition Order of Grammatical Morphemes Impervious to L1 Knowledge?LANGUAGE LEARNING, Issue 4 2009Articles, Evidence From the Acquisition of Plural - s, Possessive 's In SLA, it has been often assumed that the effect of the first language (L1) is not very strong in the acquisition of grammatical morphemes (e.g., Ellis, 1994; Mitchell & Myles, 2004). However, such an assumption has not been systematically examined in the literature. This article reviews the morpheme studies conducted with native speakers of Japanese, Korean, Chinese, and Spanish to test the effect of the L1 in the acquisition of grammatical morphemes. The review reveals that although Spanish L1 learners' acquisition order generally conforms to the "so-called" natural order (Krashen, 1977), native speakers of Japanese, Korean, and Chinese mostly acquire plural ,s,and articles later than, and possessive,'s,earlier than, is predicted by the natural order. This indicates that learners can acquire a grammatical morpheme later or earlier than predicted by the natural order, depending on the presence or absence of the equivalent category in their L1. This suggests that L1 transfer is much stronger than is portrayed in many SLA textbooks and that the role of L1 in morpheme acquisition must be reconsidered. [source] Coral Cover Change Associated to El Niño, Eastern Pacific, Costa Rica, 1992,2001MARINE ECOLOGY, Issue 3 2003Carlos E. Jiménez Abstract., Changes in live and dead coral cover were documented at three localities off the Costa Rican central Pacific coast first in 1992 during the aftermath of the 1991,1992 El Niño; again in the period between 1994 and 1995, and last in January 2001. Recovery of coral communities after the 1991,1992 El Niño was expressed by a significant increase (,40 %) in 1994 of live coral cover at one locality (Manuel Antonio). A subsequent decrease (,50 %) in response to the very strong 1997,1998 episode was recorded at Manuel Antonio and Ballena, mainly due to partial tissue mortality of branching (Pocillopora spp.) and massive (Porites lobata) corals. Mortality of entire colonies associated to that event was scarce and confined to branching and nodular (Psammocora stellata) corals. This species was not found at one locality (Cambutal) in the 2001 survey and it is presumed locally extinct. The recovery of this coral and others will depend on recruits from surviving colonies in deeper waters and other coral communities in the vicinity. Within sites at a given locality, contrasting results in live coral cover variability were found. This is partially due to distinct coral assemblages, coral growth, physical exposure to tidal regime, and, related to the latter, variable duration and intensity of the warming event. In general, predominant meteorological conditions at the studied area are conducive to solar radiation (UV) stress during El Niño years and are related to changes in the atmosphere-ocean interactions in response to the warming events. [source] Evidence for an impact on the incidence of canine leishmaniasis by the mass use of deltamethrin-impregnated dog collars in southern ItalyMEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2001M. Maroli Abstract. Dogs are the domestic reservoir of Leishmania infantum Nicolle (Kinetoplastida: Trypanosomatidae), the agent of zoonotic human visceral leishmaniasis. In southern Europe, where canine leishmaniasis (CanL) is widespread due to L. infantum, killing seropositive dogs is considered unacceptable and drug treatment has low efficacy in preventing transmission. We made a field evaluation of the efficacy of deltamethrin dog collars in a CanL focus of southern Italy, Mount Vesuvius area of Campania region, where the vector is Phlebotomus perniciosus Newstead (Diptera: Psychodidae), by assessing their impact on the incidence of CanL in an intervention town, compared to that in dogs of control towns where no collars were fitted. During two consecutive transmission seasons, collars were fitted to 350 (1998) and 354 (1999) dogs from San Sebastiano al Vesuvio (70% of the canine population). Control dogs (371 and 264 in the 2 years, respectively) were from four towns of the same area. Before each transmission season, the CanL seroprevalence in the intervention and control towns was evaluated by cross-sectional surveys and found to be similar (about 15% in 1998 and 10% in 1999, respectively). After each transmission period, incidence rates of seroconversions were determined in adult dogs that were serologically negative before the season under evaluation, and in puppies. After the 1998 season, 2.7% of the dogs in the intervention town seroconverted compared to 5.4% in the control towns (50% protection, P = 0.15). After the 1999 season, 3.5% of collared dogs seroconverted compared to 25.8% of control dogs (86% protection, P < 0.001). The increase in seroconversion rates recorded in control dogs suggests an increase in the Leishmania force of infection in the canine reservoir during the 1999 sandfly season, as supported by the concomitant increase of human cases in control towns and in the whole Campania region. Our results suggest that the impact of mass use of deltamethrin-impregnated dog collars on the incidence of CanL may be negligible during low transmission seasons, or probably in low endemic foci, but can be very strong when the force of transmission is high. [source] Statins can modulate effectiveness of antitumor therapeutic modalitiesMEDICINAL RESEARCH REVIEWS, Issue 1 2010Marek Jakobisiak Abstract Despite significant, frequently very strong, antiproliferative and tumoricidal effects of statins demonstrated in vitro, their antitumor effects in animal models are modest, and their efficacy in clinical trials has not been proven. As such, statins seem unlikely to be ever regarded as antitumor agents. However, statins are regularly taken by many elderly cancer patients for the prevention of cardiovascular events. Owing to their pleiotropic effects in normal and tumor cells, statins interact in various ways with many antitumor treatment modalities, either potentiating or diminishing their effectiveness. Elucidation of these interactions might affect the choice of treatment to be planned in cancer patients as some combinations might be contraindicated, whereas others might elicit potentiated antitumor effects but at a cost of increased general toxicity. Some other combinations might induce either comparable or even stronger antitumor effects, but with a beneficial concomitant reduction of specific side effects. Most of the studies reviewed in this article have been carried in vitro or in experimental tumor models, but clinical relevance of the findings is also discussed. © 2009 Wiley Periodicals, Inc. Med Res Rev, 30, No. 1, 102,135, 2010 [source] A Chandra observation of the H2O megamaser IC 2560MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2002K. Iwasawa Abstract A short Chandra ACIS-S observation of the Seyfert 2 galaxy IC 2560, which hosts a luminous nuclear water megamaser, shows (1) that the X-ray emission is extended; (2) that the X-ray spectrum displays emission features in the soft (E < 2 keV) X-ray band (this is the major component of the extended emission); and (3) a very strong (EW , 3.6 keV) iron K, line at 6.4 keV on a flat continuum. This last feature clearly indicates that the X-ray source is hidden behind Compton-thick obscuration, so that the intrinsic hard X-ray luminosity must be much higher than that observed, probably close to ,3 × 1042 erg s,1. We briefly discuss the implications for powering of the maser emission and the central source. [source] How do electrons travel in unusual metallic fluorides of Ag2+?,PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 1 2005Tomasz Jaro Abstract We investigate computationally two representative examples of higher fluorides of Ag(II), namely KAgF3 and AgFBF4. Both compounds formally contain linear (Ag,F)+ chains, in which divalent silver is coordinated additionally by four fluoride anions. For AgFBF4, the equatorial coordination is weak, and leads to metallic conductivity in 1D, as emerges from our band structure calculations. For KAgF3, however, the axial coordination is very strong, and the compound is virtually a 2D metal (i.e. it is mainly the x2,y2 orbitals of Ag that participate in electronic transport in this interesting material). (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] New Alternative Methods to Teach Surgical Techniques for Veterinary Medicine Students despite the Absence of Living Animals.ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2007Is that an Academic Paradox? Summary Due to a raised ethical mentality, veterinary schools are pursuing methods to preserve animal corpses used for surgical technique classes in an attempt to reduce the use of living animals for teaching. Generally speaking, animal and human bodies are usually preserved with 10% aqueous formalin solution especially for descriptive anatomy classes. Other possibilities include the use of glycerol, alcohol and phenol. At present, new fixatives have been developed to allow a better and longer preservation of animal corpses in order to maintain organoleptic characteristics, i.e. colour, texture, as close as possible to what students will deal with living animals. From 2004, in our college, surgical technique classes no longer use living animals for students' training. Instead, canine corpses chemically preserved with modified Larssen (MLS) and Laskowski (LS) solutions are preferred. The purpose of this study was to investigate comparatively the biological quality of preservation of these two solutions and to evaluate students' learning and acceptance of this new teaching method. Although these fixatives maintain body flexibility, LS solution failed to keep an ordinary tissue colouration (cadavers were intensely red) and tissue preservation was not adequate. By contrast, MLS solution, however, did not alter the colouration of cadavers which was fairly similar to that normally found in living animals. A remarkable characteristic was a very strong and unpleasant sugary odour in LS-preserved animals and therefore the MLS solution was the elected method to preserve cadavers for surgical technique classes. The students' feedback to the use of Larssen-preserved cadavers was very satisfactory, i.e. 96.6% of students were in favour of the use of cadavers for surgical training and on average 91.8% (2002,2003) of students preferred the MLS solution as the chemical preserver, whereas only 8.2% elected LS solution for teaching purposes. From the students' point of view (95.1%) the ideal class would be an initial training in MLS cadavers followed by classes with animals admitted to the Veterinary Hospital. [source] Regional Trade Agreements in East Asia: Will They Be Sustainable?,ASIAN ECONOMIC JOURNAL, Issue 2 2009Innwon Park C68; F15; O53 By assessing the sustainability of regional trade agreements (RTAs) for East Asia, we quantitatively evaluate the likely impact of proposed East Asian RTA strategies on the East Asian economies and the world economy with respect to consumption, production, volume of trade and terms of trade effects by applying a multi-country and multi-sector computable general equilibrium model. These strategies include: (i) the ASEAN Free Trade Area (AFTA: a being-left-alone strategy); (ii) an ASEAN Hub RTA (a hub-and-spoke type of overlapping RTA strategy); (iii) the AFTA versus a China,Japan,Korea RTA (a duplicating or competing RTA strategy); and (iv) an ASEAN+3 RTA (an expansionary RTA strategy). We find that an expansionary ASEAN+3 RTA could be a sustainable policy option because the members' gains would be significantly positive, with more equitably distributed gains between members than when using other strategies. The effect on world welfare would also be positive and the negative effect on nonmembers would not be very strong. More interestingly, if the East Asian countries cooperate with Pacific Basin countries to form an APEC-level RTA, such as a free trade area of the Asia-Pacific, the extension of the regional trade bloc might be considered a more desirable policy option than the proposed East Asian RTAs for East Asian economies, even though countries excluded from the free trade area of the Asia Pacific are worse off. [source] Climate and respiratory disease in Auckland, New ZealandAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 6 2009Ashmita Gosai Abstract Objective: Increases in the incidence of diseases are often observed during the cold winter months, particularly in cities in temperate climates. The study aim is to describe daily, monthly and seasonal trends in respiratory hospital admissions with climate in Auckland, New Zealand. Methods: Daily hospital admissions for total respiratory infections or inflammations (RII), total bronchitis and asthma (BA), and total whooping cough and acute bronchitis (TWCAB) for various age groups and ethnicities were obtained for the Auckland Region and compared with climate parameters on daily, monthly and seasonal time scales. Results: Seasonal and monthly relationships with minimum temperature were very strong (p<0.001) for RII over all age groups, for BA in the older age groups (14-64, 65+) and for TWCAB in the <1 year old age group. European, NZ M,ori and Pacific Islanders all showed increases in admissions as temperatures decreased. Pacific Islanders were particularly susceptible to RII. There was a lag in admissions of three to seven days after a temperature event. Conclusions and Implications: Results show that increases in respiratory admissions are strongly linked to minimum temperatures during winter, typical of cities with temperate climates and poorly-insulated houses. There are implications for hospital bed and staffing planning in Auckland hospitals. [source] Generic UMTS test signal for RF bioelectromagnetic studiesBIOELECTROMAGNETICS, Issue 6 2004H. Ndoumbè Mbonjo Mbonjo Abstract This report outlines the characteristics of universal mobile telecommunications system (UMTS) signals and discusses the signal parameters with respect to their possible biological relevance in order to define a generic UMTS test signal (GUS) for experiments aiming at the investigation of biological effects of weak electromagnetic fields. The GUS includes features of a real UMTS signal and especially the characteristics of UMTS, which differ from those of already applied second generation mobile communication systems (GSM 900, DCS1800, PCS1900, IS-95). It has been specified on the basis of the recommendations of a working group of the German Forschungsgemeinschaft Funk (FGF) with a focus on the mechanisms of UMTS which are responsible for slow term signal contributions, i.e., low frequency variations of the radio frequency (RF) envelope, since the hypothetical possibility of biological relevance of weak electromagnetic fields is often attributed to time variations of the RF envelope with frequencies close to those of natural processes. In this respect, it is also shown that the mandatory power control loop in UMTS gives rise to very strong 1.5 kHz variations on the air interface. Based upon the concept of the GUS, a UMTS test signal generator (GUS6960S) is described. Bioelectromagnetics 25:415,425, 2004. © 2004 Wiley-Liss, Inc. [source] Modification of Supramolecular Binding Motifs Induced By Substrate Registry: Formation of Self-Assembled Macrocycles and Chain-Like PatternsCHEMISTRY - A EUROPEAN JOURNAL, Issue 42 2009Leslie-Anne Fendt Abstract The self-assembly properties of two ZnII porphyrin isomers on Cu(111) are studied at different coverage by means of scanning tunneling microscopy (STM). Both isomers are substituted in their meso -positions by two voluminous 3,5-di(tert -butyl)phenyl and two rod-like 4,-cyanobiphenyl groups, respectively. In the trans -isomer, the two 4,-cyanobiphenyl groups are opposite to each other, whereas they are located at right angle in the cis -isomer. For coverage up to one monolayer, the cis- substituted porphyrins self-assemble to form oligomeric macrocycles held together by antiparallel CN,,,CN dipolar interactions and CN,,,H-C(sp2) hydrogen bonding. Cyclic trimers and tetramers occur most frequently but everything from cyclic dimers to hexamers can be observed. Upon annealing of the samples at temperatures >150,°C, dimeric macrocyclic structures are observed, in which the two porphyrins are bridged by Cu atoms, originating from the surface, under formation of two CN,,,Cu,,,NC coordination bonds. The trans -isomer builds up linear chains on Cu(111) at low coverage, whereas for higher coverage the molecules assemble in a periodic, densely packed structure. Both cis - and trans -bis(4,-cyanobiphenyl)-substituted ZnII porphyrins behave very differently on Cu(111) compared to similar porphyrins in literature on less reactive surfaces such as Au(111) and Ag(111). On the latter surfaces, there is no signal visible between molecular orientation and the crystal directions of the substrate, whereas on Cu(111), very strong adsorbate,substrate interactions have a dominating influence on all observed structures. This strong porphyrin,substrate interaction enables a much broader variety of structures, including also less favorable intermolecular bonding motifs and geometries. [source] Sequestration of Heavy Metals from Water with Layered Metal SulfidesCHEMISTRY - A EUROPEAN JOURNAL, Issue 19 2009Manolis Abstract Extraordinarily effective heavy metal ion scavenger: We show here that the material K2xMnxSn3,xS6 (x=0.5,0.95) (KMS-1) overcomes the limitations of the known heavy metal ion sorbents, showing the capability to rapidly reduce the concentrations of Cd, Hg, and Pb ions well-below the legally acceptable levels for drinking water. KMS-1 is inexpensive, easily prepared in large quantities, and may play a role in addressing the global problem of water contamination with heavy metal ions. The paradigm of heavy metal ion absorption of KMS-1 is the ability to form very strong MS bonds. [source] Direct Estimate of the Strength of Conjugation and Hyperconjugation by the Energy Decomposition Analysis MethodCHEMISTRY - A EUROPEAN JOURNAL, Issue 13 2006Israel Fernández Dr. Abstract The intrinsic strength of , interactions in conjugated and hyperconjugated molecules has been calculated using density functional theory by energy decomposition analysis (EDA) of the interaction energy between the conjugating fragments. The results of the EDA of the trans -polyenes H2CCH(HCCH)nCHCH2 (n=1,3) show that the strength of , conjugation for each CC moiety is higher than in trans -1,3-butadiene. The absolute values for the conjugation between SiSi , bonds are around two-thirds of the conjugation between CC bonds but the relative contributions of ,E, to ,Eorb in the all-silicon systems are higher than in the carbon compounds. The , conjugation between CC and CO or CNH bonds in H2CCHC(H)O and H2CCHC(H)NH is comparable to the strength of the conjugation between CC bonds. The , conjugation in H2CCHC(R)O decreases when R=Me, OH, and NH2 while it increases when R=halogen. The hyperconjugation in ethane is around a quarter as strong as the , conjugation in ethyne. Very strong hyperconjugation is found in the central CC bonds in cubylcubane and tetrahedranyltetrahedrane. The hyperconjugation in substituted ethanes X3CCY3 (X,Y=Me, SiH3, F, Cl) is stronger than in the parent compound particularly when X,Y=SiH3 and Cl. The hyperconjugation in donor,acceptor-substituted ethanes may be very strong; the largest ,E, value was calculated for (SiH3)3CCCl3 in which the hyperconjugation is stronger than the conjugation in ethene. The breakdown of the hyperconjugation in X3CCY3 shows that donation of the donor-substituted moiety to the acceptor group is as expected the most important contribution but the reverse interaction is not negligible. The relative strengths of the , interactions between two CC double bonds, one CC double bond and CH3 or CMe3 substituents, and between two CH3 or CMe3 groups, which are separated by one CC single bond, are in a ratio of 4:2:1. Very strong hyperconjugation is found in HCCC(SiH3)3 and HCCCCl3. The extra stabilization of alkenes and alkynes with central multiple bonds over their terminal isomers coming from hyperconjugation is bigger than the total energy difference between the isomeric species. The hyperconjugation in MeC(R)O is half as strong as the conjugation in H2CCHC(R)O and shows the same trend for different substituents R. Bond energies and lengths should not be used as indicators of the strength of hyperconjugation because the effect of , interactions and electrostatic forces may compensate for the hyperconjugative effect. [source] The Role of Ion Pairs in the Second-Order NLO Response of 4-X-1-Methylpiridinium Salts,CHEMPHYSCHEM, Issue 2 2010Francesca Tessore Dr. Abstract A series of 4-X-1-methylpyridinium cationic nonlinear optical (NLO) chromophores (X=(E)-CHCHC6H5; (E)-CHCHC6H4 -4,-C(CH3)3; (E)-CHCHC6H4 -4,-N(CH3)2; (E)-CHCHC6H4 -4,-N(C4H9)2; (E,E)-(CHCH)2C6H4 -4,-N(CH3)2) with various organic (CF3SO3,, p -CH3C6H4SO3,), inorganic (I,, ClO4,, SCN,, [Hg2I6]2,) and organometallic (cis -[Ir(CO)2I2],) counter anions are studied with the aim of investigating the role of ion pairing and of ionic dissociation or aggregation of ion pairs in controlling their second-order NLO response in anhydrous chloroform solution. The combined use of electronic absorption spectra, conductimetric measurements and pulsed field gradient spin echo (PGSE) NMR experiments show that the second-order NLO response, investigated by the electric-field-induced second harmonic generation (EFISH) technique, of the salts of the cationic NLO chromophores strongly depends upon the nature of the counter anion and concentration. The ion pairs are the major species at concentration around 10,3,M, and their dipole moments were determined. Generally, below 5×10,4,M, ion pairs start to dissociate into ions with parallel increase of the second-order NLO response, due to the increased concentration of purely cationic NLO chromophores with improved NLO response. At concentration higher than 10,3,M, some multipolar aggregates, probably of H type, are formed, with parallel slight decrease of the second-order NLO response. Ion pairing is dependent upon the nature of the counter anion and on the electronic structure of the cationic NLO chromophore. It is very strong for the thiocyanate anion in particular and, albeit to a lesser extent, for the sulfonated anions. The latter show increased tendency to self-aggregate. [source] | ||||||||||||||||||||||||||||