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Selected AbstractsAdditional Sources of InformationPAIN MEDICINE, Issue 2006Article first published online: 17 NOV 200 No abstract is available for this article. [source] Meta-analysis: non-pathogenic yeast Saccharomyces boulardii in the prevention of antibiotic-associated diarrhoeaALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2005H. SZAJEWSKA Summary Background :,Antibiotic-associated diarrhoea occurs in up to 30% of patients who receive antibiotics but can be prevented with probiotics. Aim :,To systematically evaluate the effectiveness of Saccharomyces boulardii in preventing antibiotic-associated diarrhoea in children and adults. Methods :,Using medical subject headings and free-language terms, the following electronic databases were searched for studies relevant to antibiotic-associated diarrhoea and S. boulardii: MEDLINE, EMBASE, CINAHL and The Cochrane Library. Additional sources were obtained from references in reviewed articles. Only randomized-controlled trials were considered for study inclusion. Results :,Of 16 potentially relevant clinical trials identified, five randomized-controlled trials (1076 participants) met the inclusion criteria for this systematic review. Treatment with S. boulardii compared with placebo reduced the risk of antibiotic-associated diarrhoea from 17.2% to 6.7% (RR: 0.43; 95% CI: 0.23,0.78; random effect model). The number needed to treat to prevent one case of antibiotic-associated diarrhoea was 10 (95% CI: 7,16). No side-effects were reported. Conclusions :,A meta-analysis of data from five randomized-controlled trials showed that S. boulardii is moderately effective in preventing antibiotic-associated diarrhoea in children and adults treated with antibiotics for any reason (mainly respiratory tract infections). For every 10 patients receiving daily S. boulardii with antibiotics, one fewer will develop antibiotic-associated diarrhoea. [source] Characterization of marine isoprene-degrading communitiesENVIRONMENTAL MICROBIOLOGY, Issue 12 2009Laura Acuña Alvarez Summary Isoprene is a volatile and climate-altering hydrocarbon with an atmospheric concentration similar to that of methane. It is well established that marine algae produce isoprene; however, until now there was no specific information about marine isoprene sinks. Here we demonstrate isoprene consumption in samples from temperate and tropical marine and coastal environments, and furthermore show that the most rapid degradation of isoprene coincides with the highest rates of isoprene production in estuarine sediments. Isoprene-degrading enrichment cultures, analysed by denaturing gradient gel electrophoresis and 454 pyrosequencing of the 16S rRNA gene and by culturing, were generally dominated by Actinobacteria, but included other groups such as Alphaproteobacteria and Bacteroidetes, previously not known to degrade isoprene. In contrast to specialist methane-oxidizing bacteria, cultivated isoprene degraders were nutritionally versatile, and nearly all of them were able to use n -alkanes as a source of carbon and energy. We therefore tested and showed that the ubiquitous marine hydrocarbon-degrader, Alcanivorax borkumensis, could also degrade isoprene. A mixture of the isolates consumed isoprene emitted from algal cultures, confirming that isoprene can be metabolized at low, environmentally relevant concentrations, and suggesting that, in the absence of spilled petroleum hydrocarbons, algal production of isoprene could maintain viable populations of hydrocarbon-degrading microbes. This discovery of a missing marine sink for isoprene is the first step in obtaining more robust predictions of its flux, and suggests that algal-derived isoprene provides an additional source of carbon for diverse microbes in the oceans. [source] VARIATION OF SHELL SHAPE IN THE CLONAL SNAIL MELANOIDES TUBERCULATA AND ITS CONSEQUENCES FOR THE INTERPRETATION OF FOSSIL SERIESEVOLUTION, Issue 2 2000Sarah Samadi Abstract., Interpreting paleontological data is difficult because the genetic nature of observed morphological variation is generally unknown. Indeed, it is hardly possible to distinguish among several sources of morphological variation including phenotypic plasticity, sexual dimorphism, within-species genetic variation or differences among species. This can be addressed using fossil organisms with recent representatives. The freshwater snail Melanoides tuberculata ranks in this category. A fossil series of this and other species have been studied in the Turkana Basin (Kenya) and is presented as one of the best examples illustrating the punctuated pattern of evolution by the tenants of this theory. Melanoides tuberculata today occupies most of the tropics. We studied variation of shell shape in natural populations of this parthenogenetic snail using Raup's model of shell coiling. We considered different sources of variation on estimates of three relevant parameters of Raup's model: (1) variation in shell shape was detected among clones, and had both genetic and environmental bases; (2) sexual dimorphism, in those clones in which males occur, appeared as an additional source of shell variation; and (3) ecophenotypic variation was detected by comparing samples from different sites and years within two clones. We then tested the performance of discriminant function analyses, a classical tool in paleontological studies, using several datasets. Although the three sources of variation cited above contributed significantly to the observed morphological variance, they could not be detected without a priori knowledge of the biological entities studied. However, it was possible to distinguish between M. tuberculata and a related thiarid species using these analyses. Overall, this suggests that the tools classically used in paleontological studies are poorly efficient when distinguishing between important sources of within-species variation. Our study also gives some empirical bases to the doubts cast on the interpretation of the molluscan series of the Turkana Basin. [source] Evidence of artificial cranial deformation from the later prehistory of the Acacus Mts. (southwestern Libya, Central Sahara)INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2008F. Ricci Abstract The 1999,2001 Italian,Libyan Archaeological Mission in the Acacus and Messak, southwestern Libya, resulted in the discovery of human specimens from the Wadi Tanezzuft Valley belonging to the Final Pastoral horizon (i.e. late Neolithic, about 3000 years bp). Some of these show clear traces of artificial cranial deformation. This practice, hitherto unrecorded in the central Sahara, is described and analysed in this paper. It represents an additional source of information about population movements and cultural connections in the area. It does not appear to be gender-related, and neither does it involve all individuals in the sample, suggesting some kind of social and/or cultural differentiation within the group. The pattern of cranial deformation described here is not directly related to types most commonly encountered among recent African populations and elsewhere. It may be considered a combination of antero-posterior and circumferential deformation and thus is referred to as a ,pseudo-circular type'. Archaeological and ethnographic literature related to Africa and southwestern Asia is investigated in order to identify a possible origin of such a custom and its pattern of diffusion. The evidence, according to other sources of information, contributes to interpret this area at the centre of the Sahara as a focal point of population movements and circulation of cultural traditions across North Africa in the latest phases of the Pastoral Neolithic. Copyright © 2008 John Wiley & Sons, Ltd. [source] Impact of eucalyptus and pine growing on rural livelihood: the lesson from Bukoba area, north western TanzaniaAFRICAN JOURNAL OF ECOLOGY, Issue 2009Phillip K. MwanukuziArticle first published online: 3 FEB 200 Abstract Sustainable resource management intends to allocate resources in such a way that unnecessary deterioration of biophysical and socio-economical systems is avoided. In Bukoba Area where rainfalls are plenty, evergreen grasslands were expansive and forests were limited, eucalypts (eucalyptus spp.) and pines (pinus spp.) were grown on grasslands for preventing land degradation through deforestation and for providing additional source of income for rural poor. This study shows that in addition to detrimental consequence of eucalyptus and pine forests on soil resources, conversion of Bukoban grasslands to forests has negatively impacted livelihood of the rural poor. Growing eucalypts and pines on grasslands prevented a farming system that enabled integration of grasslands, cattle keeping and crop production. Consequently, the grasslands role of nutrients cycling was disrupted, food crop production reduced, home-gardens productivity declined, majority deprived important livelihood asset and foreign income flow into the area reduced. [source] Short-term survival and long-term mortality of Acacia drepanolobium after a controlled burnAFRICAN JOURNAL OF ECOLOGY, Issue 3 2008B. D. Okello Abstract We investigated the short- and long-term effects of a controlled burn in Acacia drepanolobium woodland in Laikipia, Kenya in 1998. Fire temperatures averaged 250°C at ground level, with a maximum of over 500°C, but were rarely >100°C at 1.5 m above the ground or more. Nine months after the fire, virtually all A. drepanolobium trees had survived the fire. Some smaller trees were burnt to ground level, but most were only ,top-killed' and had coppiced. Taller trees suffered less damage than smaller trees. However, a 2003 satellite image suggested a dramatic reduction in A. drepanolobium canopy cover at the site. A survey of the site in 2006 revealed that the density of larger A. drepanolobium trees was nearly three times greater in adjacent control areas than in the old burn, with a lesser reduction in the density of smaller trees. These data suggest that short-term measures of postburn survivorship may be deceptive, and that an additional source of tree mortality (perhaps elephants) was concentrated on trees in burned areas, even many months after the burn, with long-term consequences for tree and ecosystem dynamics. Résumé Nous avons étudié les effets à court et à long terme d'un feu contrôlé dans la forêt àAcacia drepanolobium située à Laikipia, au Kenya, en 1998. La température du feu avoisinait les 250°C au niveau du sol, avec un maximum de 500°C, mais elle dépassait rarement les 100°C à 1,5 mètre au-dessus du sol et plus haut. Neuf mois après le feu, pratiquement tous les Acacia drepanolobium avaient survécu. Certains des arbres plus petits avaient brûlé jusqu'au ras du sol, mais chez la plupart, seule la partie aérienne avait brûlé et ils avaient fait des repousses. Les arbres plus grands avaient subi moins de dommages. Pourtant, une image satellite prise en 2003 a suggéré une réduction spectaculaire de la canopée d'A. drepanolobiumà cet endroit. Une étude du site réalisée en 2006 a révélé que la densité des plus grands A. drepanolobiumétait près de trois fois plus forte dans les zones de contrôle adjacentes que sur le site brûlé, où la densité des plus petits arbres était moins réduite. Ces données suggèrent que les mesures de la survie postincendie faites à court terme peuvent être trompeuses, et qu'une source supplémentaire de mortalité des arbres (peut-être des éléphants) s'est concentrée sur les arbres des zones brûlées, même plusieurs mois plus tard, avec des conséquences à long terme pour les arbres et la dynamique de l'écosystème. [source] Ant nest location, soil nutrients and nutrient uptake by ant-associated plants: does extrafloral nectar attract ant nests and thereby enhance plant nutrition?JOURNAL OF ECOLOGY, Issue 3 2010Diane Wagner Summary 1. As central place foragers, ants accumulate organic debris near their nests. Consequently, soil nutrient stocks are often enriched near the nest site. We investigated the hypothesis that plant-derived food sources, such as extrafloral nectar (EFN), can encourage soil-dwelling ant colonies to nest near the plant, thereby inadvertently providing the plant with an additional source of mineral nutrients. The study focused on a population of Acacia constricta, a North American shrub bearing EFNs. 2. Several lines of evidence supported the notion that food rewards drew ant nests close to A. constricta plants. Firstly, ant species that visit EFNs nested significantly closer to A. constricta plants than would be expected by chance, whereas this was not the case for two ant species that do not visit EFNs. Secondly, A. constricta plants with an ant nest occurring naturally underneath the canopy had greater foliar volume, more EFNs per leaf and more EFNs per cm of leaf rachis than plants lacking an ant nest under the canopy. Thirdly, experimental supplementation of the nectar resources on acacias led to the establishment of significantly more new nests near the plant, relative to controls. However, nectar supplementation did not affect acacia seed production within the year of the study. 3. Soil from the nests of three, EFN-visiting ant species contained higher average stocks of most mineral nutrients than nearby soils outside the influence of the nest. 4. To test whether A. constricta can assimilate the nutrients in ant nests, we fed 15N-labelled food to Dorymyrmex sp. (smithi complex) workers nesting near acacias. Twenty-four days later, the leaves of acacias with an experimentally fed ant colony under the canopy contained significantly higher 15N and %N than acacias without a nest under the canopy, indicating that acacias assimilated and benefited from nutrients derived from ants. 5.Synthesis. The results indicate that nectar resources can attract the nests of some ant species, and that plants may benefit from access to soil nutrients derived from ant nests. Our data support the hypothesis that EFNs may confer nutritive, as well as protective, benefits. [source] Neutral loss of amino acid residues from protonated peptides in collision-induced dissociation generates N- or C-terminal sequence ladders,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 11 2003Mogjiborahman Salek Abstract The widespread occurrence of the neutral loss of one to six amino acid residues as neutral fragments from doubly protonated tryptic peptides is documented for 23 peptides with individual sequences. Neutral loss of amino acids from the N-terminus of doubly charged tryptic peptides results in doubly charged y-ions, forming a ladder-like series with the ions [M + 2H]2+ = ymax2+, ymax , 12+, ymax , 22+, etc. An internal residue such as histidine, proline, lysine or arginine appears to favor this type of fragmentation, although it was sometimes also observed for peptides without this structure. For doubly protonated non-tryptic peptides with one of these residues at or near the N-terminus, we observed neutral loss from the C-terminus, resulting in a doubly charged b-type ion ladder. The analyses were performed by Q-TOF tandem mass spectrometry, facilitating the recognition of neutral loss ladders by their 2+ charge state and the conversion of the observed mass differences into reliable sequence information. It is shown that the neutral loss of amino acid residues requires low collision offset values, a simple mechanistic explanation based on established fragmentation rules is proposed and the utility of this neutral loss fragmentation pathway as an additional source for dependable peptide sequence information is documented. Copyright © 2003 John Wiley & Sons, Ltd. [source] Proton release by N2 -fixing plant roots: A possible contribution to phytoremediation of calcareous sodic soilsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 1 2003Manzoor Qadir Prof. Dr. Abstract With a world-wide occurrence on about 560 million hectares, sodic soils are characterized by the occurrence of excess sodium (Na+) to levels that can adversely affect crop growth and yield. Amelioration of such soils needs a source of calcium (Ca2+) to replace excess Na+ from the cation exchange sites. In addition, adequate levels of Ca2+ in ameliorated soils play a vital role in improving the structural and functional integrity of plant cell walls and membranes. As a low-cost and environmentally feasible strategy, phytoremediation of sodic soils , a plant-based amelioration , has gained increasing interest among scientists and farmers in recent years. Enhanced CO2 partial pressure (PCO2) in the root zone is considered as the principal mechanism contributing to phytoremediation of sodic soils. Aqueous CO2 produces protons (H+) and bicarbonate (HCO3 - ). In a subsequent reaction, H+ reacts with native soil calcite (CaCO3) to provide Ca2+ for Na+ Ca2+ exchange at the cation exchange sites. Another source of H+ may occur in such soils if cropped with N2 -fixing plant species because plants capable of fixing N2 release H+ in the root zone. In a lysimeter experiment on a calcareous sodic soil (pHs = 7.4, electrical conductivity of soil saturated paste extract (ECe) = 3.1 dS m -1, sodium adsorption ratio (SAR) = 28.4, exchangeable sodium percentage (ESP) = 27.6, CaCO3 = 50 g kg -1), we investigated the phytoremediation ability of alfalfa (Medicago sativa L.). There were two cropped treatments: Alfalfa relying on N2 fixation and alfalfa receiving NH4NO3 as mineral N source, respectively. Other treatments were non-cropped, including a control (without an amendment or crop), and soil application of gypsum or sulfuric acid. After two months of cropping, all lysimeters were leached by maintaining a water content at 130% waterholding capacity of the soil after every 24±1 h. The treatment efficiency for Na+ removal in drainage water was in the order: sulfuric acid > gypsum = N2 -fixing alfalfa > NH4NO3-fed alfalfa > control. Both the alfalfa treatments produced statistically similar root and shoot biomass. We attribute better Na+ removal by the N2 -fixing alfalfa treatment to an additional source of H+ in the rhizosphere, which helped to dissolve additional CaCO3 and soil sodicity amelioration. Protonenabgabe durch N2 -fixierende Pflanzenwurzeln: ein möglicher Beitrag zur Phytomelioration von kalkreichen Natriumböden Bei einem weltweiten Vorkommen auf etwa 560 Millionen Hektar sind Natriumböden durch einen Überschuss an Natrium (Na+) gekennzeichnet, der das Wachstum und den Ertrag von Kulturpflanzenbeständen nachteilig beeinflussen kann. Die Melioration solcher Böden erfordert Calcium (Ca2+), um überschüssiges Na+ von Kationen-Austauscherplätzen zu verdrängen. Außerdem spielt Ca2+ eine wichtige Rolle bei der Verbesserung der strukturellen und funktionellen Integrität pflanzlicher Zellwände und Membranen. Als kostengünstige und umweltfreundliche Strategie hat die Phytomelioration von Natriumböden , eine auf Pflanzen beruhende Melioration , in den letzten Jahren zunehmendes Interesse bei Wissenschaftlern und Landwirten gefunden. Ein erhöhter CO2 -Partialdruck (PCO2) in der Rhizosphäre wird als hauptsächlicher Mechanismus angesehen, der zur Phytomelioration von Natriumböden beiträgt. In Wasser gelöst, erzeugt CO2 Protonen (H+) und Bikarbonate (HCO3 - ). Anschließend reagiert H+ mit nativem Calcit (CaCO3), wobei sich Ca2+ löst und Na+ von Austauscherplätzen verdrängt. Eine weitere H+ -Quelle könnte die H+ -Abgabe von Wurzeln N2 -fixierender Pflanzen sein, da diese in der Lage sind, H+ in die Rhizosphäre abzugeben. In einem Lysimeterversuch mit einem kalkreichen Natriumboden (pHs = 7, 4; ECe = 3, 1 dS m -1; SAR = 28, 4; ESP = 27, 6; CaCO3 = 50 g kg -1) wurde die Möglichkeit einer Phytomelioration mit N2 -fixierender Luzerne (Medicago sativa L.) im Vergleich zu einer mit mineralischem N ernährten Luzerne (NH4NO3) untersucht. In weiteren Varianten (Applikation von Gips bzw. Schwefelsäure) wurde die chemische Melioration einer nicht behandelten Kontrolle gegenübergestellt. Beide Ernährungsformen führten zu statistisch ähnlicher Wurzelund Sprossmasse der Luzerne. Nach zweimonatigem Pflanzenwachstum erfolgte alle 24±1 h eine Dränung der Lysimeter durch Zugabe einer Wassermenge von 130% der maximalen Wasserkapazität zum Boden. Hinsichtlich der Effizienz, Na+ über Auswaschung aus dem Boden zu entfernen, zeigte sich folgende Reihenfolge: Schwefelsäure > Gips = N2 -fixierende Luzerne > NH4NO3 -ernährte Luzerne > Kontrolle. Wir führen das bessere Meliorationsergebnis in der Variante der N2 -fixierenden Luzerne auf eine zusätzliche H+ -Quelle in der Rhizosphäre zurück, die zur Lösung von zusätzlichem CaCO3 beitrug. [source] Some Additional Comments on the Sources and Measurement of the Benefits of Small Business Assistance ProgramsJOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 1 2002James J. Chrisman This article continues a longstanding debate between the authors and Dr. William C. Wood on the usefulness of a particular application of cost-benefit analysis to evaluate small business assistance programs. We provide further discussions of the measurement of primary and secondary benefits with specific reference to the illustrative cases Wood presented in his 1999 article. We then review Wood's suggestions for improvements to small business program evaluations and discuss the progress made in recent evaluations of small business assistance programs. Finally, we reiterate the importance of innovation as an additional source of "secondary" benefits to the economy. [source] Natural linewidth chemical shift imaging (NL-CSI)MAGNETIC RESONANCE IN MEDICINE, Issue 1 2006Adil Bashir Abstract The discrete Fourier transform (FT) is a conventional method for spatial reconstruction of chemical shifting imaging (CSI) data. Due to point spread function (PSF) effects, FT reconstruction leads to intervoxel signal leakage (Gibbs ringing). Spectral localization by imaging (SLIM) reconstruction was previously proposed to overcome this intervoxel signal contamination. However, the existence of magnetic field inhomogeneities creates an additional source of intervoxel signal leakage. It is demonstrated herein that even small field inhomogeneities substantially amplify intervoxel signal leakage in both FT and SLIM reconstruction approaches. A new CSI data acquisition strategy and reconstruction algorithm (natural linewidth (NL) CSI) is presented that eliminates effects of magnetic field inhomogeneity-induced intervoxel signal leakage and intravoxel phase dispersion on acquired data. The approach is based on acquired CSI data, high-resolution images, and magnetic field maps. The data are reconstructed based on the imaged object structure (as in the SLIM approach) and a reconstruction matrix that takes into account the inhomogeneous field distribution inside anatomically homogeneous compartments. Phantom and in vivo results show that the new method allows field inhomogeneity effects from the acquired MR signal to be removed so that the signal decay is determined only by the "natural" R2 relaxation rate constant (hence the term "natural linewidth" CSI). Magn Reson Med, 2006. © 2006 Wiley-Liss, Inc. [source] Mammalian sperm quality and aromatase expressionMICROSCOPY RESEARCH AND TECHNIQUE, Issue 8 2009Serge Carreau Abstract In most mammalian species the aromatase is encoded by a single gene (cyp19), which contains 18 exons, 9 of them being translated. In adult rats, together with Leydig cells germ cells represent an additional source of estrogens. The amount of P450arom transcript is threefold higher in pachytene spermatocytes compared to younger cells (spermatogonia-preleptotene spermatocyte) or round spermatids; conversely, aromatase activity is more intense in haploid cells. In man besides Leydig cells, we have shown the presence of a biologically active aromatase and of estrogen receptors (ER, and ERß) in immature germ cells and ejaculated spermatozoa. Concerning aromatase, a 30% decrease of the amount of mRNA is observed in immotile compared to motile sperm fraction from the same sample; moreover, the aromatase activity is diminished. We have amplified aromatase mRNA by RT-real time PCR in spermatozoa from asthenospermic, teratospermic, and asthenoteratospermic men and recorded respectively 44, 52, and 67% decreases of the amount of transcripts as compared to controls. Statistical analyses between the sperm morphology and the aromatase/GAPDH ratio have revealed a high degree of correlation (r = ,0.64) with the percentage of abnormal spermatozoa (especially microcephaly and acrosome malformations). Alterations of sperm number and motility have been described in men genetically deficient in aromatase, which together with our data, suggest a likely role for aromatase/estrogens in the acquisition of sperm motility. Therefore besides gonadotrophins and testosterone, estrogens produced locally should be considered as a physiologically relevant hormone involved in the regulation of mammalian spermatogenesis. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc. [source] Deep spectroscopy of the FUV,optical emission lines from a sample of radio galaxies at z, 2.5: metallicity and ionization,MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2008A. Humphrey ABSTRACT We present long-slit near-infrared (NIR) spectra, obtained using the Infrared Spectrometer And Array Camera (ISAAC) instrument at the Very Large Telescope, which sample the rest-frame optical emission lines from nine radio galaxies at z, 2.5. One-dimensional spectra have been extracted and, using broad-band photometry, have been cross-calibrated with spectra from the literature to produce line spectra spanning a rest wavelength of ,1200,7000 Å. The resulting line spectra have a spectral coverage that is unprecedented for radio galaxies at any redshift. We have also produced a composite of the rest-frame ultraviolet (UV),optical line fluxes of powerful, z, 2.5 radio galaxies. We have investigated the relative strengths of Ly,, H,, H,, He ii,1640 and He ii,4687, and we find that Av can vary significantly from object to object. In addition, we have identified new line ratios to calculate electron temperature: [Ne v],1575/[Ne v],3426, [Ne iv],1602/[Ne iv],2423, O iii],1663/[O iii],5008 and [O ii],2471/[O ii],3728. We calculate an average O iii temperature of 14100+1000,600 K. We have modelled the rich emission line spectra, and we conclude that they are best explained by active galactic nucleus (AGN) photoionization with the ionization parameter U varying between objects. For shock models (with or without the precursor) to provide a satisfactory explanation for the data, an additional source of ionizing photons is required , presumably the ionizing radiation field of the AGN. Single slab photoionization models are unable to reproduce the high- and the low-ionization lines simultaneously: the higher ionization lines imply higher U than do the lower ionization lines. This problem may be alleviated either by combining two or more single slab photoionization models with different U, or by using mixed-medium models such as those of Binette, Wilson & Storchi-Bergmann. In either case, U must vary from object to object. On the basis of N v/N iv] and N iv]/C iv we argue that, while photoionization is the dominant ionization mechanism in the extended emission line regions (EELR), shocks make a fractional contribution (,10 per cent) to its ionization. The N v/N iv] and N iv]/C iv ratios in the broad-line region (BLR) of some quasars suggest that shock ionization may be important in the BLR also. We find that in the EELR of z, 2 radio galaxies the N/H abundance ratio is close to its solar value. We conclude that N/H and metallicity do not vary by more than a factor of 2 in our sample. These results are consistent with the idea that the massive ellipticals which become the hosts to powerful AGN are assembled very early in the history of the universe, and then evolve relatively passively up to the present day. [source] Use of neurodevelopmental delay in pediatric solid organ transplant listing decisions: Inconsistencies in standards across major pediatric transplant centersPEDIATRIC TRANSPLANTATION, Issue 7 2009Christopher T. Richards Abstract:, Children with NDD present for organ transplant evaluation, but the role of NDD as a listing criterion itself is poorly described. Therefore, we sought to investigate how major pediatric solid organ transplant programs use NDD as a criterion in their listing decisions. We developed a survey that was sent via post to active pediatric solid organ transplant programs across the United States investigating transplant listing decision-making for neurodevelopmentally delayed children. Respondents were medical/surgical directors and transplant coordinators. Descriptive statistics summarize the findings. Programs inconsistently use NDD in listing decisions. Thirty-nine percent of programs stated that they "rarely" or "never" consider NDD in their decisions, whereas 43% of programs "always" or "usually" do. Sixty-two percent of programs report that informal processes guide their use of NDD, and no programs describe their process as "formal, explicit, and uniform." The degree of delay is an additional source of discordance among programs, with 14% of programs reporting mild or moderate NDD as a relative contraindication to listing and 22% reporting that NDD was "irrelevant" to the listing decision. The use of NDD in pediatric solid organ transplant listing decisions is varied and inconsistent across active programs. [source] Multiple Sources of Metals of Mineralization in Lower Cambrian Black Shales of South China: Evidence from Geochemical and Petrographic StudyRESOURCE GEOLOGY, Issue 1 2008Jan Pa Abstract Black shales of the Lower Cambrian Niutitang Formation in southern China (Huangjiawan mine, Zunyi region, northern part of the Guizhou Province) host regionally distributed stratiform polymetallic Ni-Mo-platinum group elements (PGE)-Au phosphate- and sulfide-rich ores. These are confined to a ,0.2-m thick ore horizon composed of mineralized bodies of algal onkolites, phosphate nodules, and sulfide and shale clasts in a mineralized phosphate- and organic matter-rich matrix. Compared to footwall and hanging wall shales, the ore bed is strongly enriched in Ni (up to 100-fold), As (up to 97-fold), Mo (up to 95-fold), Sb (up to 67-fold), Rh (up to 49-fold), Cu (up to 37-fold), Pd (up to 33-fold), Ru (up to 24-fold), Zn (up to 23-fold), Pt (up to 21-fold), Ir (up to 15-fold), Co (up to 14-fold), and Pb (up to 13-fold). Even footwall and hanging wall black shales are significantly enriched by Mo (21-fold) and Ni (12-fold) but depleted in Cr in comparison to average Cambrian black shale. Organic matter is represented by separate accumulations dispersed in the rock matrix or as biotic bitumen droplets and veinlets in ore clasts. Similar organic carbon (Corg) values in an ore bed and enclosing footwall and hanging wall shales of little mineralization indicate that metal accumulation was not controlled only by biogenic productivity and organic matter accumulation rate. Evaporitic conditions during sedimentation of the basal part of the Niutitang Formation were documented by an occurrence of preserved Ni-, V-, Cr-, and Cu-enriched phosphate-rich hardground with halite and anhydrite pseudomorphs on the paleosurface of the underlying Neoproterozoic carbonates. Neoproterozoic black shales of the Doushantuo Formation are characterized by increased metal concentrations. Comparison of metal abundances in both hardground and Doushantuo black shales indicate that black shales could have become a source of metal-rich hardground during weathering. The polymetallic Ni-Mo-PGE sulfide-rich ore bed is interpreted to represent a remnant of shallow-water hardground horizon rich in metals, which originated in a sediment-starved, semi-restricted, seawater environment. During the Early Cambrian transgression an influx of fresh seawater and intensive evaporation, together with the hydrothermal enrichment of seawater in a semi-restricted basin, resulted in the formation of dense metalliferous brines; co-precipitation of metals together with phosphates and sulfides occurred at or above the oxic,anoxic sediment interface. Metal-enriched hardground was disintegrated by the action of waves or bottom currents and deposited in a deeper part of the anoxic basin. Contemporaneously with the formation of a polymetallic Ni-Mo-PGE-Au sulfide ore bed, economic sedimentary exhalative (SEDEX)-type barite deposits were forming in a stratigraphically and geotectonically similar setting. The results of geochemical study at the Shang Gongtang SEDEX-type Ba deposit indicate that concentrations of Ag, As, Cr, Cu, Fe, Mn, Ni, Pb, Sb, V, Zn and other metals decrease from top of the barite body toward the hanging wall black shale. Lower Cambrian black shales of the Niutitang Formation above the barite body also display similar element abundances as Neoproterozoic black shales of the Doushantuo Formation, developed in the footwall of the barite body. But the geochemical composition of the sulfide layer is different from the Ni-Mo ore bed, showing only elevated Pb, Cu, Ni and Mo values. It is suggested that hydrothermal brines at Shang Gongtang might have leached metals from footwall Neoproterozoic sequences and became, after mixing with normal seawater, an additional source of Ag, Cr, Cu, Pb, Sb, Zn, Ni, PGE, V and other metals. [source] Combining Information from Cancer Registry and Medical Records Data to Improve Analyses of Adjuvant Cancer TherapiesBIOMETRICS, Issue 3 2009Yulei He Summary Cancer registry records contain valuable data on provision of adjuvant therapies for cancer patients. Previous studies, however, have shown that these therapies are underreported in registry systems. Hence direct use of the registry data may lead to invalid analysis results. We propose first to impute correct treatment status, borrowing information from an additional source such as medical records data collected in a validation sample, and then to analyze the multiply imputed data, as in Yucel and Zaslavsky (2005,,Journal of the American Statistical Association,100, 1123,1132). We extend their models to multiple therapies using multivariate probit models with random effects. Our model takes into account the associations among different therapies in both administration and probability of reporting, as well as the multilevel structure (patients clustered within hospitals) of registry data. We use Gibbs sampling to estimate model parameters and impute treatment status. The proposed methodology is applied to the data from the Quality of Cancer Care project, in which stage II or III colorectal cancer patients were eligible to receive adjuvant chemotherapy and radiation therapy. [source] Jack Tizard Memorial Lecture: Educational Reform and the Mental Health of Vulnerable Children and Young PeopleCHILD AND ADOLESCENT MENTAL HEALTH, Issue 4 2001David Galloway Although research has demonstrated the differential influence of schools on children's psychosocial adjustment, the influence of radical legislative changes since 1979 is less clear. Evidence of a sharp rise in exclusions and in referral for special educational needs is contrasted with evidence that behaviour in most schools is good, and with data showing a steep reduction in the number of pupils leaving school with no qualifications. It is argued that these reforms have improved overall standards and may thereby have contributed positively to the mental health of many vulnerable children. However, the way they have been implemented has undermined teachers in some schools and, as a result, pupils there experience education as an additional source of stress rather than of stability and support. [source] School breakfast clubs, children and family support,CHILDREN & SOCIETY, Issue 2 2003Ian Shemilt School breakfast clubs are a form of before school provision serving breakfast to children who arrive early. This paper explores their potential to provide support for families at risk of social exclusion. A national evaluation of a Department of Health pilot initiative suggests that their provision can afford valued support to families coping with varying degrees of difficulty in their material, environmental, relational and social circumstances. Many parents regarded clubs as successful in encouraging children to eat breakfast, reducing pressures in the morning and providing an additional source of affordable, trusted child care to those in work, studying or seeking employment. Copyright © 2002 John Wiley & Sons, Ltd. [source] No evidence for switching the antidepressant: systematic review and meta-analysis of RCTs of a common therapeutic strategyACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010T. Bschor Bschor T, Baethge C. No evidence for switching the antidepressant: systematic review and meta-analysis of RCTs of a common therapeutic strategy. Objective:, Switching antidepressants is a common strategy for managing treatment-resistant depressed patients. However, no systematic reviews have been conducted to date. Method:, We systematically searched MEDLINE/EMBASE/Cochrane Central Register of Controlled Trials and additional sources. We included double-blind studies of patients with depressive symptomatology who were not responding to initial antidepressant monotherapy and were subsequently randomized to another antidepressant or to continue the same antidepressant. Results were pooled for meta-analysis of response + remission rates using a fixed-effects model. Results:, A total of three studies were included. Switching to another antidepressant was not superior to continuing the initial antidepressant in any of these studies. Our meta-analysis showed no significant advantages to either strategy and no significant heterogeneity of results [OR for response rates: 0.85 (95% CI: 0.55,1.30) favoring continuing]. Conclusion:, There is a discrepancy between the published evidence and the frequent decision to switch antidepressants, indicating an urgent need for more controlled studies. Pending such studies we recommend that physicians rely on more thoroughly evaluated strategies. [source] Greenhouse gas buildup, sardines, submarine eruptions and the possibility of abrupt degradation of intense marine upwelling ecosystemsECOLOGY LETTERS, Issue 11 2004Andrew Bakun Abstract Widespread hypoxia and massive eruptions of noxious, radiatively active gases currently characterize the world's strongest eastern ocean upwelling zone. Theory, modelling results and observations suggest that the world's coastal upwelling zones will undergo progressive intensification in response to greenhouse gas buildup. This presents the prospect of progressive development of similarly degraded marine ecosystems in additional regions and of a contributing feedback loop involving associated additions to the global buildup rate of greenhouse gases, resulting further increases in upwelling intensity, creation of additional sources of greenhouse gas emissions, and so on. Abundant sardine stocks might be a mitigating factor opposing the process. [source] Osseous abnormalities associated with collateral desmopathy of the distal interphalangeal joint.EQUINE VETERINARY JOURNAL, Issue 8 2009Part 2: Treatment, outcome Summary Reasons for performing study: There are currently few long-term follow-up data relating to recovery from injury of a collateral ligament (CL) of the distal interphalangeal (DIP) joint and limited information about the effect of associated osseous injury on prognosis. Objectives: To describe long-term follow-up results for horses with CL injury, with and without associated osseous injury; and to determine the effect of extracorporeal shock wave therapy (ECSWT) or radial pressure wave therapy (RPWT) on outcome. Hypotheses: Prognosis for return to performance for horses with CL-related osseous injury would be worse than for horses with CL injury alone. Methods: Magnetic resonance images from 313 feet of 289 horses with foot pain and a definitive diagnosis of collateral desmopathy of the DIP joint were analysed retrospectively for presence of osseous abnormality associated with the ligament origin or insertion and the middle and distal phalanges. Horses were assigned to groups according to the combination of their injuries. Type of treatment was recorded and follow-up information obtained. Thirty-two horses with additional sources of lameness were excluded from analysis of outcome. Results: Follow-up data were available for 182 horses, 55 of which had follow-up information for up to 2 years after presentation. Twenty-seven percent of horses with CL injury alone and 34% of horses with CL related osseous injury returned to their previous performance level. Prognosis for a combination of injuries to multiple soft tissue and osseous structures within the hoof capsule was substantially worse. There was no effect of ECSWT or RPWT on outcome. Conclusions: The presence of mild to moderate CL related osseous injury does not appear to influence prognosis compared with CL injury alone. Clinical relevance: Further studies of a larger number of horses are necessary in order to ascertain if specific types of osseous pathology influence return to performance levels. [source] A LIKELIHOOD FRAMEWORK FOR INFERRING THE EVOLUTION OF GEOGRAPHIC RANGE ON PHYLOGENETIC TREESEVOLUTION, Issue 11 2005Richard H. Ree Abstract At a time when historical biogeography appears to be again expanding its scope after a period of focusing primarily on discerning area relationships using cladograms, new inference methods are needed to bring more kinds of data to bear on questions about the geographic history of lineages. Here we describe a likelihood framework for inferring the evolution of geographic range on phylogenies that models lineage dispersal and local extinction in a set of discrete areas as stochastic events in continuous time. Unlike existing methods for estimating ancestral areas, such as dispersal-vicariance analysis, this approach incorporates information on the timing of both lineage divergences and the availability of connections between areas (dispersal routes). Monte Carlo methods are used to estimate branch-specific transition probabilities for geographic ranges, enabling the likelihood of the data (observed species distributions) to be evaluated for a given phylogeny and parameterized paleogeographic model. We demonstrate how the method can be used to address two biogeographic questions: What were the ancestral geographic ranges on a phylogenetic tree? How were those ancestral ranges affected by speciation and inherited by the daughter lineages at cladogenesis events? For illustration we use hypothetical examples and an analysis of a Northern Hemisphere plant clade (Cercis), comparing and contrasting inferences to those obtained from dispersal-vicariance analysis. Although the particular model we implement is somewhat simplistic, the framework itself is flexible and could readily be modified to incorporate additional sources of information and also be extended to address other aspects of historical biogeography. [source] Larval lobster (Homarus americanus) distribution and drift in the vicinity of the Gulf of Maine offshore banks and their probable originsFISHERIES OCEANOGRAPHY, Issue 2 2005G. C. HARDING Abstract Surveys for lobster larvae in offshore waters of the north-eastern Gulf of Maine in 1983, 1987 and 1989 confirm that local hatching occurs mainly at depths <100 m over the banks, including Georges and Browns Banks. Detailed studies in the vicinity of Georges Bank in late July of both 1987 and 1989 indicate that the first and second moult stages were located primarily over the bank whereas stages III and IV lobster were collected both over and off the bank. At times stage IV lobster were more abundant off the bank than over it. The condition of stage III and IV lobster, as measured by a lipid index, was better off than over Georges Bank in 1988 and 1989 indicating a possible physiological advantage to being off the bank. In addition, the higher surface temperatures off Georges Bank would shorten larval development time to settlement. To determine the probable hatch sites of stage IV lobster collected off of Browns Bank in 1983 and off of Georges in 1987 and 1989, a 3-D circulation model of the Gulf of Maine was used to simulate larval lobster drift backwards in time. In all cases, areas off Cape Cod, MA, and off Penobscot Bay, ME were suggested as the source of the larvae, although most of the larval trajectories never reached these near-shore waters that are well-known, larval hatching areas. The model-projected larval release times match most closely the observed inshore hatch off Massachusetts but model uncertainties mean that coastal Maine cannot be ruled out as a source. Georges Bank is also a potential source because the present model does not take into account short-term wind events, off-bank eddy transport or the possibility of directed off-bank larval swimming. Examination of weather records prior to and during our 1988 and 1989 sampling periods indicates that winds were not of sufficient intensity and duration to induce larval transport off Georges Bank. The shedding of eddies from the northern flank of Georges Bank into the Gulf of Maine are a relatively common phenomenon during summer but not enough is known about them to evaluate their contribution to possible cross-bank transport of lobster larvae. Directed larval swimming is another possible source for the stage IV lobster found near Georges Bank. Plankton distributions across the northern frontal zone of Georges Bank in 1988 were used as proxies for the scarce larval lobsters. The more surface distribution of the microplankton, in particular, supports the possibility that wind and eddy events may be important in the transport of stage III and IV lobsters off of Georges Bank. Further studies are needed to evaluate these possible additional sources of advanced stage lobster larvae found off of the offshore banks. [source] The global financial crisis of 2008,2009: an opportunity for development studies?JOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 6 2010James Copestake Abstract This paper draws upon the five other papers presented in this volume, along with other presentations made at the 2009 Development Studies Association Conference, to reflect on the relationship between development studies and the 2008,2009 global financial crisis. It first analyses antecedents to the crisis by relating the papers presented by Gore (on long waves of capitalism) and Fischer (on China's integration into the world economy) to a Polanyian analysis. It then considers immediate policy responses with particular reference to India (based on the conference presentation by Mehrotra), China (based on the paper by de Haan) and the 2009 DFID White Paper. Third, it considers two possible additional sources of finance for developing countries: South Korean aid (discussed by Chun et al.) and new forms of international money (discussed by Hudson). The paper concludes that while the crisis is a reminder of structural global economic interconnectedness a challenge for development studies is to combine this fact with analysis that is also interdisciplinary, multi-tiered and policy relevant. Copyright © 2010 John Wiley & Sons, Ltd. [source] Synchronous peak Barrovian metamorphism driven by syn-orogenic magmatism and fluid flow in southern Connecticut, USAJOURNAL OF METAMORPHIC GEOLOGY, Issue 5 2008P. J. LANCASTER Abstract Recent work in Barrovian metamorphic terranes has found that rocks experience peak metamorphic temperatures across several grades at similar times. This result is inconsistent with most geodynamic models of crustal over-thickening and conductive heating, wherein rocks which reach different metamorphic grades generally reach peak temperatures at different times. Instead, the presence of additional sources of heat and/or focusing mechanisms for heat transport, such as magmatic intrusions and/or advection by metamorphic fluids, may have contributed to the contemporaneous development of several different metamorphic zones. Here, we test the hypothesis of temporally focussed heating for the Wepawaug Schist, a Barrovian terrane in Connecticut, USA, using Sm,Nd ages of prograde garnet growth and U,Pb zircon crystallization ages of associated igneous rocks. Peak temperature in the biotite,garnet zone was dated (via Sm,Nd on garnet) at 378.9 ± 1.6 Ma (2,), whereas peak temperature in the highest grade staurolite,kyanite zone was dated (via Sm,Nd on garnet rims) at 379.9 ± 6.8 Ma (2,). These garnet ages suggest that peak metamorphism was pene-contemporaneous (within error) across these metamorphic grades. Ion microprobe U,Pb ages for zircon from igneous rocks hosted by the metapelites also indicate a period of syn-metamorphic peak igneous activity at 380.6 ± 4.7 Ma (2,), indistinguishable from the peak ages recorded by garnet. A 388.6 ± 2.1 Ma (2,) garnet core age from the staurolite,kyanite zone indicates an earlier episode of growth (coincident with ages from texturally early zircon and a previously published monazite age) along the prograde regional metamorphic T,t path. The timing of peak metamorphism and igneous activity, as well as the occurrence of extensive syn-metamorphic quartz vein systems and pegmatites, best supports the hypothesis that advective heating driven by magmas and fluids focussed major mineral growth into two distinct episodes: the first at c. 389 Ma, and the second, corresponding to the regionally synchronous peak metamorphism, at c. 380 Ma. [source] Score tests for heterogeneity and overdispersion in zero-inflated Poisson and binomial regression modelsTHE CANADIAN JOURNAL OF STATISTICS, Issue 3 2002Daniel B. Hall Abstract Hall (2000) has described zero-inflated Poisson and binomial regression models that include random effects to account for excess zeros and additional sources of heterogeneity in the data. The authors of the present paper propose a general score test for the null hypothesis that variance components associated with these random effects are zero. For a zero-inflated Poisson model with random intercept, the new test reduces to an alternative to the overdispersion test of Ridout, Demério & Hinde (2001). The authors also examine their general test in the special case of the zero-inflated binomial model with random intercept and propose an overdispersion test in that context which is based on a beta-binomial alternative. Tests scores d'hétérogénéité et de surdispersion dans des modéles de régression binomiaux et de Poisson avec surplus de zéros Hall (2000) a décrit des modèles de régression binomiaux et de Poisson dans lesquels des effets aléatoires servent à expliquer certaines sources d' hétérogénéité dans les données, dont un surplus de zéros. Les auteurs du présent article proposent un test score général permettant de vérifier si les composantes de la variance associées à ces effets aléatoires sont nulles. Pour un modèle de Poisson à surplus de zéros et à ordonnée aléatoire, le nouveau test se compare au test de surdispersion de Ridout, Demétrio & Hinde (2001). Les auteurs étudient en outre leur test général dans le cadre du modèle binomial à surplus de zéros et à ordonnée aléatoire, pour lequel ils proposent un test de surdispersion adapté à des contre-hypothèses de type b,ta-binomial. [source] The Triple P-Positive Parenting Programme: a universal population-level approach to the prevention of child abuseCHILD ABUSE REVIEW, Issue 3 2003Matthew R. Sanders Abstract The Triple P-Positive Parenting Programme is described as an example of an evidence-based universal parenting initiative that provides a tiered continuum of interventions of increasing strength but narrowing reach in an effort to make parenting programmes more accessible to parents. Interventions within the system range from the use of the media and brief messages to intensive family interventions for parents where parenting problems are complicated by multiple additional sources of family adversity. Several issues concerning the role of training and organizational factors that influence the successful uptake and implementation of the programme are discussed. Copyright © 2003 John Wiley & Sons, Ltd. [source] Breastfeeding promotion for infants in neonatal units: a systematic reviewCHILD: CARE, HEALTH AND DEVELOPMENT, Issue 2 2010M. J. Renfrew Abstract Background Breastfeeding/breastmilk feeding of infants in neonatal units is vital to the preservation of short- and long-term health, but rates are very low in many neonatal units internationally. The aim of this review was to evaluate the effectiveness of clinical, public health and health promotion interventions that may promote or inhibit breastfeeding/breastmilk feeding for infants admitted to neonatal units. Methods Systematic review with narrative synthesis. Studies were identified from structured searches of 19 electronic databases from inception to February 2008; hand searching of bibliographies; Advisory Group members helped identify additional sources. Inclusion criteria: controlled studies of interventions intended to increase breastfeeding/feeding with breastmilk that reported breastmilk feeding outcomes and included infants admitted to neonatal units, their mothers, families and caregivers. Data were extracted and appraised for quality using standard processes. Study selection, data extraction and quality assessment were independently checked. Study heterogeneity prevented meta-analysis. Results Forty-eight studies were identified, mainly measuring short-term outcomes of single interventions in stable infants. We report here a sub-set of 21 studies addressing interventions tested in at least one good-quality or more than one moderate-quality study. Effective interventions identified included kangaroo skin-to-skin contact, simultaneous milk expression, peer support in hospital and community, multidisciplinary staff training, and Unicef Baby Friendly accreditation of the associated maternity hospital. Conclusions Breastfeeding/breastmilk feeding is promoted by close, continuing skin-to-skin contact between mother and infant, effective breastmilk expression, peer support in hospital and community, and staff training. Evidence gaps include health outcomes and costs of intervening with less clinically stable infants, and maternal health and well-being. Effects of public health and policy interventions and the organization of neonatal services remain unclear. Infant feeding in neonatal units should be included in public health surveillance and policy development; relevant definitions are proposed. [source] Phylogeny of the sea spiders (Arthropoda, Pycnogonida) based on direct optimization of six loci and morphologyCLADISTICS, Issue 3 2007Claudia P. Arango Higher-level phylogenetics of Pycnogonida has been discussed for many decades but scarcely studied from a cladistic perspective. Traditional taxonomic classifications are yet to be tested and affinities among families and genera are not well understood. Pycnogonida includes more than 1300 species described, but no systematic revisions at any level are available. Previous attempts to propose a phylogeny of the sea spiders were limited in characters and taxon sampling, therefore not allowing a robust test of relationships among lineages. Herein, we present the first comprehensive phylogenetic analysis of the Pycnogonida based on a total evidence approach and Direct Optimization. Sixty-three pycnogonid species representing all families including fossil taxa were included. For most of the extant taxa more than 6 kb of nuclear and mitochondrial DNA and 78 morphological characters were scored. The most parsimonious hypotheses obtained in equally weighted total evidence analyses show the two most diverse families Ammotheidae and Callipallenidae to be non-monophyletic. Austrodecidae + Colossendeidae + Pycnogonidae are in the basal most clade, these are morphologically diverse groups of species mostly found in cold waters. The raising of the family Pallenopsidae is supported, while Eurycyde and Ascorhynchus are definitely separated from Ammotheidae. The four fossil taxa are grouped within living Pycnogonida, instead of being an early derived clade. This phylogeny represents a solid framework to work towards the understanding of pycnogonid systematics, providing a data set and a testable hypothesis that indicate those clades that need severe testing, especially some of the deep nodes of the pycnogonid tree and the relationships of ammotheid and callipallenid forms. The inclusion of more rare taxa and additional sources of evidence are necessary for a phylogenetic classification of the Pycnogonida. © The Willi Hennig Society 2006. [source] | ||||||||||||||||||||||||||||||||||