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Group Being (group + being)
Selected AbstractsDepositional environment and sequence architecture of the Silurian Coralliferous Group, Southern Pembrokeshire, UKGEOLOGICAL JOURNAL, Issue 3 2002Robert D. Hillier Abstract The Lower Silurian siliciclastic Coralliferous Group is shown to have been deposited in an intra-shelf position 10,15,km south of the palaeogeographic shelf-break of the Welsh Basin. After a phase of thermal subsidence related to the development of the predominantly Llandovery Skomer Volcanic Group, the shelf basin was transgressed. This transgression was punctuated by an episode of tectonic uplift in southern Pembrokeshire, resulting in subaerial exposure of the shelf and a significant basinward shift in sedimentary environments. Erosion and sediment bypass ensued, with coarse-grained low-sinuosity fluvial channels transporting sediment to the northerly Welsh Basin, where significant submarine fans developed. During the early Telychian, renewed transgression took place, with lowstand gravels being ravined and reworked into parasequences of the transgressive systems tract. These thin, coarse-grained parasequences record deposition within high-energy wave-dominated shoreface/inner shelf environments. Further coastal onlap resulted in the closing down of significant coarse-grained sediment supply, with the remaining Coralliferous Group being dominated by wave-influenced silts, mud-shales and thin sandstones comprising the highstand systems tract. Copyright © 2002 John Wiley & Sons, Ltd. [source] Drinking goal selection and treatment outcome in out-patients with mild-moderate alcohol dependenceDRUG AND ALCOHOL REVIEW, Issue 4 2001SIMON J. ADAMSON Abstract Selection of drinking goal is examined at baseline, post-treatment and at 6 months follow-up for a sample of mild-moderate alcohol-dependent out-patients. Drinking goal is identified as abstinent or controlled drinking, with the latter group being asked to further specify per session and per week drinking limits. Group comparisons for drinking goal post-treatment show those who were not assigned motivational enhancement therapy, had more drinking days and lower scores on the Alcohol Problems Questionnaire and Internal Motivation were more likely to choose controlled drinking. The only variable to predict independently whether or not the controlled drinking goal was within the promoted drinking guidelines was age, with younger participants more likely to choose a goal above this limit. Goal selection was significantly related to drinking outcome, with those aiming to drink within guidelines having better outcome than those aiming for higher limits. There was no significant difference in drinking outcome category when those aiming for within limits were compared to those aiming for abstinence. Clinical implications of these findings are discussed. [source] Effects of plant invasions on the species richness of abandoned agricultural landECOGRAPHY, Issue 6 2001Scott J. Meiners While exotic plant invasions are thought to lead to declines in native species, the long-term impacts of such invasions on community structure are poorly known. Furthermore, it is unknown how exotic plant invasions compare to invasions by native species. We present data from 40 yr of continuous vegetation sampling of 10 fields released from agriculture to examine the effects of invasions on species richness. The effects of both exotic and native species invasions on species richness were largely driven by variations among fields with most species not significantly affecting species richness. However, invasion and dominance by the exotics Agropyron repens, Lonicera japonica. Rosa multiflora. Trifolium pratense and the native Solidago canadensis were associated with declines in richness. Invasions by exotic and native species during old field succession have similar effects on species richness with dominance by species of either group being associated with loss of species richness. Exotic species invasions tended to have stronger effects on richness than native invasions. No evidence was found of residual effects of invasions because the impact of the invasion disappeared with the decline of the invading population. When pooled across species, heavy invasion by exotic species resulted in greater loss o species richness than invasion by native species. Studies of invasion that utilize multiple sites must account for variability among sites. In our study, had we no included field as a factor we would have incorrectly concluded that invasion consistently resulted in changes in species richness. [source] Synthesis and Comparative Glycosidase Inhibitory Properties of Reducing Castanospermine AnaloguesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2005Paula Díaz Pérez Abstract The feasibility of the intramolecular nucleophilic addition of the nitrogen atom in cyclic (thio)carbamates with a pseudo- C -nucleoside structure to the masked carbonyl group in aldose precursors in the synthesis of reducing (i.e., 5-hydroxy)6-oxaindolizidine frameworks is illustrated by the preparation of the 6- epi, 7- epi, 8- epi and 6,8a-di- epi diastereomers of the potent glycosidase inhibitor (+)-castanospermine. In all cases, the increased anomeric effect caused by the high sp2 character of the pseudoamide-type nitrogen atom resulted in the pseudoanomeric hydroxy group being anchored in an axial orientation in aqueous solution, as in the aglycons in ,-glycosides. These analogs of the natural alkaloid showed a higher selectivity in the inhibition of ,-glucosidases. Structure/glycosidase inhibitory activity studies indicated that inversion of any hydroxy group resulted in a dramatic decrease in the inhibition potency, confirming the critical importance of a correct hydroxylation profile. In the case of (+)-8- epi -6-oxacastanospermine derivatives, with a hydroxylation profile with a structural complementarity to that of D -galactose, a moderate but very selective inhibition of ,-galactosidase was observed, supporting the importance of a defined configuration at pseudoanomeric centres for anomeric specificity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] An in vitro comparison of three thermal gutta percha systemsINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2001M. P. Horrocks Aim,The aim of this study was to compare the ability of three contemporary obturation techniques to resist microleakage, using root canals prepared in extracted single rooted teeth by a standardized method. Methodology,The shaping technique involved the use of tapered nickel titanium rotary files to create a uniform 0.08-mm/mm taper. Six groups were compared, two representing control groups, a third group being obturated with a warm vertical condensation technique, a fourth group by an injection thermoplasticized system, a fifth group with a thermomechanical compaction method and a sixth group using cold lateral condensation. A zinc oxide/eugenol sealer was used as the sealant in all the obturation procedures. Forty-six extracted teeth were used in the study, three teeth in each control group and 10 teeth in each of the remaining four groups. Microleakage was compared using dye leakage with Indian ink. Penetration of the dye at the gutta percha/dentine interface was visualized after the root had been rendered transparent. Dye leakage was then measured from four aspects with the use of a stereomicroscope and export of a digital image to a software package, to facilitate accurate assessment of dye penetration. Two parameters were measured for each sample, the mean dye penetration and maximum dye penetration. Results,The mean values for linear dye leakage in the thermomechanical compaction group was 0.53 mm, the warm vertical condensation group was 0.73 mm, the injection thermoplasticized group was 0.15 mm and the cold lateral condensation group was 0.53 mm. There was no statistical difference between the means of the different groups (P > 0.05). The mean of the maximum values for dye leakage in the thermomechanical compaction group was 0.65 mm, the warm vertical condensation group was 1.02 mm, the injection-thermoplasticized group was 0.28 mm and the cold lateral condensation group was 0.74 mm. There was no statistical difference between the means of the different groups (P > 0.05). Conclusions,Within the conditions of this study, there was no statistical difference between the different groups with respect to either mean or maximum dye leakage. [source] Representing species in reserves from patterns of assemblage diversityJOURNAL OF BIOGEOGRAPHY, Issue 7 2004M. B. Araújo Abstract Aim, A positive relationship between assemblage diversity (AD) , equivalent to the biotic version of the environment diversity, ED, method , and species diversity has been reported. This being true, reserve networks with many different assemblages would be expected to represent more species than reserve networks including fewer and less different assemblages. This idea was tested using European species atlas distributions of terrestrial vertebrates and plants. It is asked whether: (1) maximizing AD within one group would represent species diversity of this group better than expected by chance; and (2) maximizing AD within one group would represent species diversity of other groups better than expected by chance. Location, Europe. Methods, Three ordination techniques (non-metric multidimensional scaling, detrended correspondence analysis and correspondence analysis) are used to summarize patterns of compositional turnover within assemblages. p -Median location-allocation models are then calculated from ordination space to measure the degree of expected species representation within the group being sampled as well as the expected representation within other groups. Results are compared with near-optimal solutions obtained with complementarity-based algorithms and to a null model obtained by simulating selection of areas at random. Matrix correlation analysis was also performed to investigate broad patterns of covariation in compositional turnover of assemblages of species belonging to different taxonomic groups and these values were compared with correlation in species richness scores between groups. Results, The AD model did not always represent more species of the group being sampled than expected by chance (P < 0.05). Results were independent of the method and taxonomic group considered. Effectiveness of AD within one group to represent species of other groups varied, but in most cases it was worse than using complementarity-based algorithms as a surrogate strategy. Even when correlations indicated high coincidence between assemblages, taxonomic-based surrogates did not always recover more species than expected by chance (P < 0.05). Main conclusions, Results are discussed in the light of two possible explanations: (1) the AD model is based on unrealistic assumptions, namely that species have equal probability of having the centre of their distributions anywhere in ordination space and that species display unimodal, symmetrical, bell-shaped response curves to gradients; (2) particular implementation of methods may be inadequate to summarize useful complementarity among assemblages, especially for restricted-range species. We conclude that both arguments are likely to play a role in explaining results, but that opportunities exist to improve performance of existing surrogate strategies. [source] Theoretical studies on four-membered ring compounds with NF2, ONO2, N3, and NO2 groupsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 4 2008Xiao-Wei Fan Abstract Density functional theory (DFT) method has been employed to study the geometric and electronic structures of a series of four-membered ring compounds at the B3LYP/6-311G** and the B3P86/6-311G** levels. In the isodesmic reactions designed for the computation of heats of formation (HOFs), 3,3-dimethyl-oxetane, azetidine, and cyclobutane were chosen as reference compounds. The HOFs for N3 substituted derivations are larger than those of oxetane compounds with ONO2 and/or NF2 substituent groups. The HOFs for oxetane with ONO2 and/or NF2 substituent groups are negative, while the HOFs for N3 substituted derivations are positive. For azetidine compounds, the substituent groups within the azetidine ring affect the HOFs, which increase as the difluoroamino group being replaced by the nitro group. The magnitudes of intramolecular group interactions were predicted through the disproportionation energies. The strain energy (SE) for the title compounds has been calculated using homodesmotic reactions. For azetidine compounds, the NF2 group connecting N atom in the ring decrease the SE of title compounds. Thermal stability were evaluated via bond dissociation energies (BDE) at the UB3LYP/6-311G** level. For the oxetane compounds, the ONO2 bond is easier to break than that of the ring CC bond. For the azetidine and cyclobutane compounds, the homolysises of CNX2 and/or NNX2 (X = O, F) bonds are primary step for bond dissociation. Detonation properties of the title compounds were evaluated by using the Kamlet,Jacobs equation based on the calculated densities and HOFs. It is found that 1,1-dinitro-3,3-bis(difluoroamino)-cyclobutane, with predicted density of ca. 1.9 g/cm3, detonation velocity (D) over 9 km/s, and detonation pressure (P) of 41 GPa that are lager than those of TNAZ, is expected to be a novel candidate of high energy density materials (HEDMs). The detonation data of nitro-BDFAA and TNCB are also close to the requirements for HEDMs. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008 [source] The relative effects and equity of inquiry-based and commonplace science teaching on students' knowledge, reasoning, and argumentationJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 3 2010Christopher D. Wilson Abstract We conducted a laboratory-based randomized control study to examine the effectiveness of inquiry-based instruction. We also disaggregated the data by student demographic variables to examine if inquiry can provide equitable opportunities to learn. Fifty-eight students aged 14,16 years old were randomly assigned to one of two groups. Both groups of students were taught toward the same learning goals by the same teacher, with one group being taught from inquiry-based materials organized around the BSCS 5E Instructional Model, and the other from materials organized around commonplace teaching strategies as defined by national teacher survey data. Students in the inquiry-based group reached significantly higher levels of achievement than students experiencing commonplace instruction. This effect was consistent across a range of learning goals (knowledge, reasoning, and argumentation) and time frames (immediately following the instruction and 4 weeks later). The commonplace science instruction resulted in a detectable achievement gap by race, whereas the inquiry-based materials instruction did not. We discuss the implications of these findings for the body of evidence on the effectiveness of teaching science as inquiry; the role of instructional models and curriculum materials in science teaching; addressing achievement gaps; and the competing demands of reform and accountability. © 2009 Wiley Periodicals, Inc. J Res Sci Teach 47:276,301, 2010 [source] Theoretical Study on Thermodynamic and Detonation Properties of PolynitrocubanesPROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 2 2009Xue-Hai Ju Abstract We investigated the heat of formation (,fH) of polynitrocubanes using density functional theory B3LYP and HF methods with 6-31G*, 6-311+G**, and cc-pVDZ basis sets. The results indicate that ,fH firstly decreases (nitro number m=0,2) and then increases (m=4,8) with each additional nitro group being introduced to the cubane skeleton. ,fH of octanitrocubane is predicted to be 808.08,kJ mol,1 at the B3LYP/6-311+G** level. The Gibbs free energy of formation (,fG) increases by about 40,60,kJ mol,1 with each nitro group being added to the cubane when the substituent number is fewer than 4, then ,fG increases by about 100,110,kJ mol,1 with each additional group being attached to the cubic skeleton. Both the detonation velocity and the pressure for polynitrocubanes increase as the number of substituents increases. Detonation velocity and pressure of octanitrocubane are substantially larger than the famous widely used explosive cyclotetramethylenetetranitramine (HMX). [source] Two polymorphs of N -(2,6-difluorophenyl)formamideACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2009Bernard Omondi The structures of two distinct polymorphic forms of N -(2,6-difluorophenyl)formamide, C7H5F2NO, have been studied using single crystals obtained under different crystallizing conditions. The two forms crystallize in different space groups, viz. form (Ia) in the orthorhombic Pbca and form (Ib) in the monoclinic P21 space group. Each polymorph crystallizes with one complete molecule in the asymmetric unit and they have a similar molecular geometry, showing a trans conformation with the formamide group being out of the plane of the aromatic ring. The packing arrangements of the two polymorphs are quite different, with form (Ia) having molecules that are stacked in an alternating arrangement, linked into chains of N,H...O hydrogen bonds along the crystallographic a direction, while form (Ib) has its N,H...O hydrogen-bonded molecules stacked in a linear fashion. A theoretical study of the two structures allows information to be gained regarding other contributing interactions, such as ,,, and weak C,H...F, in their crystal structures. [source] The zwitterion of 4-nitro-2-{(E)-[2-(piperidin-1-yl)ethyl]iminomethyl}phenolACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2009Rocio J. Santos-Contreras The title Schiff base compound, 4-nitro-1-oxo-2-{(E)-[2-(piperidin-1-yl)ethyl]iminiomethyl}cyclohexadienide, C14H19N3O3, exists as a zwitterion, with the H atom of the phenol group being transferred to the imine N atom. The C=O, CAr,CAr and C,N bond lengths are in agreement with the oxocyclohexadienide,iminium zwitterionic form. The iminium H atom is engaged in a strong intramolecular hydrogen bond with the O atom of the keto group (N+,H...O) to form an S(6) motif. Soft C,H...O interactions in the ac plane lead to the development of hydrogen-bonded tapes, which are ,-stacked through the oxocyclohexadienide ring and iminium group. The significance of this study is in providing crystallographic evidence, supported by NMR and IR data, of the predominance of the oxocyclohexadienide,iminium zwitterion form over the noncharged canonical form in the title Schiff base. [source] Noncorrelated effects of seed predation and pollination on the perennial herb Ruellia nudiflora remain spatially consistentBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009LUIS ABDALA-ROBERTS By simultaneously manipulating both seed predator and pollinator effects on the perennial herb Ruellia nudiflora at two sites in Yucatan (Mexico), the present study evaluated (1) whether a correlation (interaction) existed between seed predator and pollinator effects on R. nudiflora seed production and (2) whether such an interaction varied geographically. We used three populations per site, and a total of 20 plants per population (N = 120). Groups of five plants were randomly chosen at each population to simultaneously receive one of two seed predator and pollinator exclosure levels (present or excluded in each case). These two factors were fully crossed, resulting in each group being subjected to one of four possible combinations: pollinators excluded/herbivores present; herbivores excluded/pollinators present; herbivores excluded/pollinators excluded; or control (neither excluded). Response variables were the number of seeds produced per plant and the proportion of attacked fruits by seed predators per plant. Seed predators had a large impact on R. nudiflora seed production but did not show any preference for fruits from plants not excluded from pollinators. In addition, the pollination treatment was not significant, indicating no effect of pollinators on reproductive success. These findings resulted in a nonsignificant herbivory × pollination interaction, which was consistent across sites, indicating lack of correlated selection of these two guilds on R. nudiflora seed production. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 800,807. [source] Implementation of kangaroo mother care: A randomized trial of two outreach strategiesACTA PAEDIATRICA, Issue 7 2005Robert C Pattinson Abstract Aim: To test whether a well-designed educational package on the implementation of kangaroo mother care (KMC) used on its own can be as effective in implementing KMC in a healthcare facility as the combination of a visiting facilitator used in conjunction with the package. Setting: Thirty-four hospitals in KwaZulu-Natal Province, South Africa. Method: The hospitals were paired with respect to their geographical location and annual number of births at the facility. One hospital in each pair was randomly allocated to receive either the implementation package alone (group A) or the implementation package and visits from a facilitator (group B). Hospitals in group B received three facilitation visits. All hospitals were evaluated by a site visit 8 mo after launching the process and were scored by means of a progress-monitoring tool. Outcomes: Successful implementation was regarded as demonstrating evidence of practice (score>10) during the site visit. Results: Group B scored significantly better than group A (p<0.05). All 17 hospitals in group B demonstrated evidence of practice, with the median score of the group being 15.44 (range 10.29,22.94). Twelve of the hospitals in group A demonstrated evidence of practice and the median score was 11.33 (range 1.08,21.13). Conclusion: Successful implementation was achieved in most of the hospitals irrespective of the strategy used. However, facilitation with an implementation package was clearly superior to using a package alone. Some sites do not need facilitation for successful implementation. [source] | ||||||||||||||||