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1.
Abstract

The ichnospecies Gastrochaneolites dijugus Kelly and Bromley 1984 Kelly, S. R. A., and R. G. Bromley. 1984. “Ichnological Nomenclature of Clavate Borings.” Palaeontology 27: 793807.[Web of Science ®] [Google Scholar] and Teredolites longissimus Kelly and Bromley 1984 Kelly, S. R. A., and R. G. Bromley. 1984. “Ichnological Nomenclature of Clavate Borings.” Palaeontology 27: 793807.[Web of Science ®] [Google Scholar], attributed to the boring activity of gastrochaenoid and pholadid bivalves, are described respectively from the Miocene Vilanova Basin and the Pliocene Almería-Níjar Basin. Miocene and Pliocene traces are preserved as positive casts associated to invertebrate shells and wood fragments, respectively; in both cases, the host substrate (shells and wood) has been lost almost entirely by different taphonomic processes (mainly dissolution). For the first time in the fossil record, the complete ichnogenetic sequence of these two ichnospecies is described and figured.  相似文献   

2.
Abstract

The association of vertebrate remains and invertebrate traces, although less studied than other bioerosion traces, provides important paleoecological information. This report describes Cubiculum ornatum Roberts, Rogers, and Foreman 2007 Roberts, E., R. Rogers, and B. Foreman. 2007. Continental insect borings in dinosaur bone: examples from the Late Cretaceous of Madagascar and Utah. Journal of Paleontology 81(1):201208.[Crossref], [Web of Science ®] [Google Scholar], Osteocallis Roberts, Rogers, and Foreman 2007 Roberts, E., R. Rogers, and B. Foreman. 2007. Continental insect borings in dinosaur bone: examples from the Late Cretaceous of Madagascar and Utah. Journal of Paleontology 81(1):201208.[Crossref], [Web of Science ®] [Google Scholar] and other unidentified insect traces from the dermal skeletal remains of glyptodonts found in Uruguay. They come from the Fray Bentos Formation (Late Oligocene), the Camacho Formation (Late Miocene) and the Dolores Formation (Late Pleistocene-Early Holocene). The reported traces were likely made by sarcosaprophagous beetles, which indicate depositional conditions with dry episodes in a warm climate for the referred stratigraphical units.  相似文献   

3.
ABSTRACT

This commentary extends and amplifies aspects of the Cantor, Osher, Berg, Steyer and Rose (2018 Cantor, P., Osher, D., Berg, J., Steyer, L., & Rose, T. (2018). Maleability, plasticity, and individuality: How children learn and develop in context. Applied Developmental Science. doi:10.1080/10888691.2017.1398649[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) discussion about what we know about the nature of learning and its implications for how we educate students across the span from early childhood through advanced levels of formal education. The paper’s overall goal is to offer some guidance and clarification about how aspects of the Cantor et al. (2018 Cantor, P., Osher, D., Berg, J., Steyer, L., & Rose, T. (2018). Maleability, plasticity, and individuality: How children learn and develop in context. Applied Developmental Science. doi:10.1080/10888691.2017.1398649[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) powerful vision of optimal and equitable development might be attained based on a view of what we mean by learning, the types of learning that matter, and ways to design environments for learning and development that allow all children to realize their potential. Three major topics are covered. The first concerns evolution of theories of learning as they relate to theories of development and the connection between the two. Emphasis is given to the power that comes from adopting a sociocultural perspective on the nature of learning and development. The second topic is a consideration of current targets of learning and development, including so-called 21st century competencies and deep disciplinary learning. Emphasis is given to the cognitive, intrapersonal and interpersonal competency domains that integrate cognitive, affective, social and emotional processes. The third topic focuses on a set of research-based principles that can be used to design and implement powerful and equitable learning environments that align with sociocultural theories and learning and development while integrating the three major domains of competency.  相似文献   

4.
Abstract

Quercetin is an important flavonoid compound, usually extracted from plants, vegetables and fruits such as blueberries, apples, green tea, wine, onions and possessing broad range of pharmacological properties, in particular, powerful antioxidant, antitoxic, antiinflammation and antimicrobial effects due to its various reactive sites. The structure of this phenolic compound consists of three (A?+?C) and B rings, bearing five hydroxyl groups. Primarily, the chemical structure of quercetin determines its physico-chemical properties. Earlier, it was established that isolated quercetin molecule can acquire 48 stable conformations (24 planar and 24 non-planar) due to the mobility of its hydroxyl groups and (A?+?C) and B rings with relative Gibbs free energies in the range of 0.0–25.3?kcal·mol?1 under normal conditions (Brovarets’ et al., 2019c Brovarets’, O. O., & Hovorun, D. M. (2019c). Conformational diversity of the quercetin molecule: A quantum-chemical view. Journal of Biomolecular Structure and Dynamics. doi: 10.1080/07391102.2019.1645734[Taylor & Francis Online], [Web of Science ®] [Google Scholar]). In this work by quantum-mechanical calculations at the MP2/6-311++G(2df,pd)//B3LYP/6-311++G(d,p) level of theory and Bader’s ‘Quantum Theory of Atoms in Molecules’, we have theoretically modeled the interconversions in the 24 pairs of the conformers of the quercetin molecule, occuring via the rotation of its non-deformable (A+С) and B rings around the С2-С1' bond through the quasi-orthogonal transition state with low values of the imaginary frequencies (28–33/29–36?cm?1) and Gibbs free energies of activation in the range of 2.17–5.68/1.86–4.90?kcal·mol?1 in the continuum with dielectric permittivity ε?=?1/ε?=?4 under normal conditions. Also, we studied the changes of the number of physico-chemical characteristics of all intramolecular-specific contacts – hydrogen bonds and attractive van der Waals contacts during these conformational rearrangements.

Communicated by Ramaswamy H. Sarma  相似文献   

5.
6.
Abstract

Sinusichnus Gibert 1996 Gibert, J. M. d. 1996. “A New Decapod Burrow System from the NW Mediterranean Pliocene.” Revista Española de Paleontología 11: 251254. [Google Scholar] is recorded for the first time in the Oligocene-Miocene Pirabas Formation of Northern Brazil. In these Oligocene-Miocene carbonate deposits, Sinusichnus sinuosus is characterized by horizontal, highly regular sinusoidal burrow systems with T- and H-shaped branching points. The main difference between the S. sinuosus described herein and other occurrences worldwide is the anomalous diameter of the burrows (4 to 10?cm). These trace fossils occur in organic matter-rich, wackestone/packstone and laminated mudstones interbedded with boundstones deposited in an inner carbonate platform paleoenvironment. The exceptional size of the studied S. sinuosus could have been associated to the producer’s size, which may be attributed to construction by large crustaceans, similar to fossils found within the Pirabas Formation. Also, the sinusoidal morphology and retrusive spreiten could be a result of the fodinichnial/domichnial behavior.  相似文献   

7.
We address several conjectures raised in Cantrell et al. [Evolution of dispersal and ideal free distribution, Math. Biosci. Eng. 7 (2010), pp. 17–36 [9 Cantrell, R. S., Cosner, C. and Lou, Y. 2010. Evolution of dispersal and ideal free distribution. Math. Biosci. Eng., 7: 1736. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]]] concerning the dynamics of a diffusion–advection–competition model for two competing species. A conditional dispersal strategy, which results in the ideal free distribution of a single population at equilibrium, was found in Cantrell et al. [9 Cantrell, R. S., Cosner, C. and Lou, Y. 2010. Evolution of dispersal and ideal free distribution. Math. Biosci. Eng., 7: 1736. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]]. It was shown in [9 Cantrell, R. S., Cosner, C. and Lou, Y. 2010. Evolution of dispersal and ideal free distribution. Math. Biosci. Eng., 7: 1736. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]] that this special dispersal strategy is a local evolutionarily stable strategy (ESS) when the random diffusion rates of the two species are equal, and here we show that it is a global ESS for arbitrary random diffusion rates. The conditions in [9 Cantrell, R. S., Cosner, C. and Lou, Y. 2010. Evolution of dispersal and ideal free distribution. Math. Biosci. Eng., 7: 1736. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]] for the coexistence of two species are substantially improved. Finally, we show that this special dispersal strategy is not globally convergent stable for certain resource functions, in contrast with the result from [9 Cantrell, R. S., Cosner, C. and Lou, Y. 2010. Evolution of dispersal and ideal free distribution. Math. Biosci. Eng., 7: 1736. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]], which roughly says that this dispersal strategy is globally convergent stable for any monotone resource function.  相似文献   

8.
Public familiarity with basic scientific concepts and principles has been proposed as essential for effective democratic decision-making (Miller, 1998 Miller, J. D. 1998. The measurement of civic scientific literacy. Public Understanding of Science, 7: 20323. [Crossref], [Web of Science ®] [Google Scholar]). Empirical research, however, finds that public ‘scientific literacy’ is generally low, falling well short of what normative criteria would consider ‘acceptable’. This has prompted calls to better engage, educate and inform the public on scientific matters, with the additional, usually implicit assumption that a knowledgeable citizenry should express more supportive and favourable attitudes toward science. Research investigating the notion that ‘to know science is to love it’ has provided only weak empirical support and has itself been criticised for representing science and technology as a unified and homogenous entity. In practice, it is argued, how knowledge impacts on the favourability of attitudes will depend on a multiplicity of factors, not least of which is the particular area of science in question and the technologies to which it gives rise (Evans & Durant, 1992 Evans, G. and Durant, J. 1992. The relationship between knowledge and attitudes in the public understanding of science in Britain. Public Understanding of Science, 4: 5774.  [Google Scholar]). This article uses a new method for examining the knowledge-attitude nexus on a prominent area of 21st century science—biotechnology. The idea that greater scientific knowledge can engender change in the favourability of attitudes toward specific areas of science is investigated using data from the 2000 British Social Attitudes Survey and the 1999 Wellcome Consultative Panel on Gene Therapy. Together the surveys measure public opinion on particular applications of genetic technologies, including gene therapy and the use of genetic data, as well as more general attitudes towards genetic research. We focus our analysis on how two different measures of knowledge impact on these attitudes; one a general measure of scientific knowledge, the other relating specifically to knowledge of modern genetic science. We investigate what impact these knowledge domains have on attitudes towards biotechnology using a regression-based modelling technique (Bartels, 1996 Bartels, L. M. 1996. Uninformed votes: information effects in presidential elections. American Journal of Political Science, 40(1): 194230. [Crossref], [Web of Science ®] [Google Scholar]; Althaus, 1998 Althaus, S. L. 1998. Information effects in collective preferences. The American Political Science Review, 92(3): 54558. [Crossref], [Web of Science ®] [Google Scholar]; Sturgis, 2003 Sturgis, P. 2003. Knowledge and collective preferences: a comparison of two approaches to estimating the opinions of a better-informed public. Sociological Methods and Research, 31(4): 45385. [Crossref] [Google Scholar]). Controlling for a range of socio-demographic characteristics, we provide estimates of what collective and individual opinion would look like if everyone were as knowledgeable as the currently best-informed members of the general public on the knowledge domains in question. Our findings demonstrate that scientific knowledge does appear to have an important role in determining individual and group attitudes to genetic science. However, we find no support for a simple ‘deficit model’ of public understanding, as the nature of the relationship itself depends on the application of biotechnology in question and the social location of the individual.  相似文献   

9.
10.
In Disney/Pixar's phenomenally popular animated film Finding Nemo (Stanton, 2003 Stanton, A. Writer/Director. 2003. Finding Nemo [Motion picture], United States: Pixar Animation Studios.  [Google Scholar]), one of the central themes of fish welfare was highlighted when the moorish idol, Gill, commented, “Fish aren't meant to be kept in a box, kid. It does things to you.” The notion that fish might have the capacity to suffer in captivity (Chandroo, Duncan, & Moccia, 2004a Chandroo, K. P., Duncan, I. J. H and Moccia, R. D. 2004a. Can fish suffer?: Perspectives on sentience, pain, fear and stress. Applied Animal Behaviour Science, 86: 225250. [Crossref], [Web of Science ®] [Google Scholar], 2004b Chandroo, K. P., Duncan, I. J. H and Moccia, R. D. 2004b. An evaluation of current perspectives on consciousness and pain in fish. Fish and Fisheries, 5: 281295. [Crossref], [Web of Science ®] [Google Scholar]) links to the larger question of sentiency, which remains a fundamental tenet when justifying concerns for nonhuman animal welfare (Dawkins, 2006 Dawkins, M. S. 2006. Through animal eyes: What behaviour tells us. Applied Animal Behaviour Science, 100: 410. [Crossref], [Web of Science ®] [Google Scholar]; Huntingford et al., 2006 Huntingford, F. A., Adams, C., Braithwaite, V. A., Kadri, S., Pottinger, T. G.Sandoe, P. 2006. Review paper: Current issues in fish welfare. Journal of Fish Biology, 68: 332372. [Crossref], [Web of Science ®] [Google Scholar]). Although terrestrial nonhuman-animal welfare has been discussed and explored for many years, the development of aquatic animal welfare concepts and approaches remains relatively new and beyond public awareness (Braastad, Damsgård, & Juell, 2006; Broom, 2007 Broom, D. M. 2007. Cognitive ability and sentience: Which aquatic animals should be protected?. Disease of Aquatic Organisms, 75: 99108. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]; Farmed Animal Welfare Council, 1996; Fisheries Society of the British Isles, 2002; Håstein, Scarfe, & Lund, 2005; Iwama, 2007 Iwama, G. K. 2007. The welfare of fish. Diseases of Aquatic Organisms, 75: 155158. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]; Schreck, 1981 Schreck, C. B. 1981. “Stress and compensation in teleostean fishes: Response to social and physical factors”. In Stress and fish, Edited by: Pickering, A. D. 295321. London: Academic.  [Google Scholar]).  相似文献   

11.
This paper considers the local, field-scale sustainability of a productive industrial maize agrosystem that has replaced a fertile grassland ecosystem.

Using the revised thermodynamic approach of Svirezhev (1998 Svirezhev, Y. M. 1998. “Thermodynamic orientors: How to use Thermodynamic concepts in ecology”. In Eco Targets, Goal Functions, and Orientors, 102122. Berlin: Springer Verlag. [Crossref] [Google Scholar], 2000 Svirezhev, Y. M. 2000. Thermodynamics and ecology. Ecological Modelling, 132: 1122. [Crossref], [Web of Science ®] [Google Scholar]) and Steinborn and Svirezhev (2000) Steinborn, W. and Svirezhev, Y. M. 2000. Entropy as an indicator of sustainability in agro-ecosystems: North Germany case study. Ecol. Mode., 133: 247257. [Crossref], [Web of Science ®] [Google Scholar], it is shown that currently this agrosystem is unsustainable in the U.S., with or without tilling the soil. The calculated average erosion rates of soil necessary to dissipate the entropy produced by U.S. maize agriculture, 23–45 t ha?1 yr?1, are bounded from above by an experimental estimate of mean soil erosion by conventional agriculture worldwide, 47 t ha?1 yr?1, (Montgomery, 2007 Montgomery, D. R. 2007. Soil erosion and agricultural sustainability. PNAS, 104(33): 1326813272. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]). Between 1982 and 1997, US agriculture caused an estimated 7–23 t ha?1 yr?1 of average erosion with the mean of 15 t ha?1 yr?1 (USDA-NRCS Database). The lower mean erosion rate of no till agriculture, 1.5 t ha?1 yr?1 (Montgomery, 2007 Montgomery, D. R. 2007. Soil erosion and agricultural sustainability. PNAS, 104(33): 1326813272. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]), necessitates the elimination of weeds and pests with field chemicals—with the ensuing chemical and biological soil degradation, and chemical runoff—to dissipate the produced entropy. The increased use of field chemicals that replace tillers is equivalent to the killing or injuring of up to 300 kg ha?1 yr?1 of soil flora and fauna. Additional soil degradation, not calculated here, occurs by acidification, buildup of insoluble metal compounds, and buildup of toxic residues from field chemicals. The degree of unsustainability of an average U.S. maize field is high, requiring 6–13 times more energy to reverse soil erosion and degradation, etc., than the direct energy inputs to maize agriculture. This additional energy, if spent, would not increase maize yields. The calculated “critical yield” of “organic” maize agriculture that does not use field chemicals and fossil fuels is only 30 percent lower than the average maize yield of 8.7 tons per hectare (~140 bu/acre) assumed here. This critical yield would not likely be achieved and sustained by large monocultures, but might be achieved by more balanced organic polycultures (Baum et al., 2008 Baum, A. W., Patzek, T. W., Bender, M., Renich, S. and Jackson, W. 2008. The Visible, Sustainable Farm: A Comprehensive Energy Analysis of a Midwestern Farm 134. Posted at petroleum.berkeley.edu/papers/Biofuels/SSF?Report3-051408.pdf [Google Scholar]).  相似文献   


12.
The natural remobilization of an initially static mixed dense non-aqueous phase liquid (DNAPL) pool due to dissolution was demonstrated by (Roy et al. 2002 Roy, J. W., Smith, J. E. and Gillham, R. W. 2002. Natural remobilization of multicomponent DNAPL pools due to dissolution. J. Contam. Hydrol., 59: 163186. [Crossref], [PubMed], [Web of Science ®] [Google Scholar], 2004 Roy, J. W., Smith, J. E. and Gillham, R. W. 2004. Laboratory evidence of natural remobilization of multicomponent DNAPL pools due to dissolution. J. Contam. Hydrol., 74: 145161. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]) using a compositional mathematical model and laboratory experiments with open pools over a porous medium. The purposes of this study were to: a) demonstrate natural remobilization for a pool within porous media (as opposed to an open pool); and b) analyze the capillary effects associated with residual formation, a changing saturation profile, hysteresis, and aging, as these processes may reduce the potential for natural remobilization of pools in porous media. DNAPL pools comprised of tetrachloroethene and benzene were created within a zone of larger glass beads overlying smaller glass beads, in a water-saturated 2-D flow cell. In one case, remobilization occurred in the form of a DNAPL finger, after 56 days of flushing. In another case, no remobilization had occurred after 64 days of flushing, though the density increased by 430 kg m ?3 and remobilization was predicted by the compositional model. Comparison of observations with model predictions suggest that contact angle hysteresis, related to an observed change in wettability, was the most significant contributing factor causing overprediction of the potential for natural remobilization.  相似文献   

13.
Gobies (Gobiidae sensu Gill & Mooi, 2012 Gill, A. and Mooi, R. 2012. Thalasseleotrididae, new family of marine gobioid fishes from New Zealand and temperate Australia, with a revised definition of its sister taxon, the Gobiidae (Teleostei: Acanthomorpha). Zootaxa, 3266: 4152.  [Google Scholar]) are one of the most diverse families of vertebrates, and comprise over 1700 species of marine, brackish and freshwater fishes. Phylogenetic studies based on morphological characters and mtDNA have suggested that goby diversity is asymmetrically split between a speciose clade of predominantly marine species, and a less rich, but ecologically diverse, clade comprising predominantly freshwater and brackish species. This study is the first to explore this deep divide in gobies and their relationships at the family level using phylogenetic data from nuclear genes (RAG1, rhodopsin). Our results confirm the split within the Gobiidae, and agree with prior molecular studies on the inclusion of the following taxa within the two goby clades: (i) the more diverse of the two clades of gobies (the ‘Gobiidae’ sensu stricto of Thacker 2009 Thacker, C. E. 2009. Phylogeny of Gobioidei and placement within Acanthomorpha, with a new classification and investigation of diversification and character evolution. Copeia, 1: 93104. doi:10.1643/CI-08-004[Crossref], [Web of Science ®] [Google Scholar]) comprises the gobiines, microdesmines, ptereleotrines and kraemeriines; (ii) the less diverse of the two gobiid clades (‘Gobionellidae’ sensu Thacker 2009 Thacker, C. E. 2009. Phylogeny of Gobioidei and placement within Acanthomorpha, with a new classification and investigation of diversification and character evolution. Copeia, 1: 93104. doi:10.1643/CI-08-004[Crossref], [Web of Science ®] [Google Scholar]) includes the gobionellines, oxudercines, amblyopines, sicydiines, as well as the European sand gobies. Some relationships within the two major gobiid clades remain unclear. Specifically, there remains confusion regarding the monophyly and interrelationships between the northern Pacific gobionellines, the Mugilogobius group gobionellines, and the European sand gobies. Additionally, within Thacker's (2009 Thacker, C. E. 2009. Phylogeny of Gobioidei and placement within Acanthomorpha, with a new classification and investigation of diversification and character evolution. Copeia, 1: 93104. doi:10.1643/CI-08-004[Crossref], [Web of Science ®] [Google Scholar]) Gobiidae sensu stricto, there are several well-supported groups (e.g. the wormfishes and dartfishes, the Coral Gobies, the Gobiosomatini), yet relationships among these groups are still poorly resolved despite the use of data from two conserved nuclear genes. Future phylogenetic analyses of gobies will benefit greatly from taxon sampling that includes groups that have been historically under-represented in molecular studies (e.g. European sand gobies, northern Pacific gobionellines, African species), as well as deeper genetic sampling including large numbers of independent loci from throughout the genome (i.e. a phylogenomic approach).  相似文献   

14.
An automated, iterative approach to finding the lowest energy, ionic diffusion paths through a periodic structure has been developed within our new code (written in FORTRAN 77 and named Bubble). The approach is quite general in that it can be applied to find, at a chosen temperature, the accessible (ergodic) regions of a hyper-surface, which is defined across a uniform grid [1 Schön, J.C., Putz, H. and Jansen, M. 1996. Studying the energy hypersurface of continuous system—The threshold algorithm. J. Phys.-Conden. Matt., 8: 143[Crossref] [Google Scholar]]. We describe both our implementation within the Bubble code and its application to locating the approximate transition states for Mg interstitial diffusion in forsterite, which can then be refined using standard transition state searching [2 Banerjee, A., Adams, N., Simons, J. and Shepard, R. 1985. Search for stationary points on surfaces. J. Phys. Chem., 89: 52[Crossref], [Web of Science ®] [Google Scholar]].  相似文献   

15.

Copper(I)-catalyzed 5-endo-dig cyclizations of 5-(alkyn-1-yl)uracil derivatives had given poor yields of substituted furo[2 Robins, M. J. and Barr, P. J. 1983. Nucleic acid related compounds. 39. Efficient conversion of 5-iodo to 5-alkynyl and derived 5-substituted uracil bases and nucleosides. J. Org. Chem, 48: 18541862. [CSA][CROSSREF][Crossref], [Web of Science ®] [Google Scholar], 3 De Clercq, E., Descamps, J., Balzarini, J., Giziewicz, J., Barr, P. J. and Robins, M. J. 1983. Nucleic acid related compounds. 40. Synthesis and biological activities of 5-alkynyluracil nucleosides. J. Med. Chem, 26: 661666. [PUBMED][INFOTRIEVE][CSA][CROSSREF][Crossref], [PubMed], [Web of Science ®] [Google Scholar]]pyrimidin-2-ones unless the uracil ring was substituted at N1 with alkyl or glycosyl groups. This limited flexibility for the synthesis of analogues with varied substituents at N3 and/or C6 of the furo[2 Robins, M. J. and Barr, P. J. 1983. Nucleic acid related compounds. 39. Efficient conversion of 5-iodo to 5-alkynyl and derived 5-substituted uracil bases and nucleosides. J. Org. Chem, 48: 18541862. [CSA][CROSSREF][Crossref], [Web of Science ®] [Google Scholar], 3 De Clercq, E., Descamps, J., Balzarini, J., Giziewicz, J., Barr, P. J. and Robins, M. J. 1983. Nucleic acid related compounds. 40. Synthesis and biological activities of 5-alkynyluracil nucleosides. J. Med. Chem, 26: 661666. [PUBMED][INFOTRIEVE][CSA][CROSSREF][Crossref], [PubMed], [Web of Science ®] [Google Scholar]]pyrimidin-2-one core has been overcome with 5-(3-hydroxyalkyn-1-yl)uracil compounds with no substituent at N1. Manipulation of the side-chain hydroxyl group gives access to additional furo[2,3-d]pyrimidin-2-one analogues.  相似文献   

16.
Recent adaptationist accounts of human mental and physical health have reinvigorated the debate over the evolution of human intelligence. In the tradition of strong inference the current study was developed to determine whether either Miller's (1998 Miller, G. F. 1998. “How mate choice shaped human nature: A review of sexual selection and human evolution”. In Handbook of evolutionary psychology: Ideas, issues, and applications, Edited by: Crawford, C. and Krebs, D. 87129. Hillsdale, NJ: Lawrence Erlbaum.  [Google Scholar], 2000a Miller, G. F. 2000a. Mental traits as fitness indicators: Expanding evolutionary psychology's adaptationism. Evolutionary approaches to human reproductive behavior. Ann N Y Acad Sci, 907: 6274. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]) Fitness Indicator Theory or Rushton's (1985 Rushton, J. P. 1985. Differential K theory: The sociobiology of individual and group differences. Pers Indiv Diff, 6(4): 441452. [Crossref] [Google Scholar], 2000 Rushton, J. P. 2000. Race, evolution, and behavior: A life-history perspective, 3rd, Port Huron, MI: Charles Darwin Research Institute.  [Google Scholar]) Differential-K Theory better accounts for general intelligence (“g”) in an undergraduate university population (N = 192). Owing to the lengthy administration time of the test materials, a newly developed 18-item short form of the Ravens Advanced Progressive Matrices (APM-18; Sefcek, Miller, and Figueredo 2007 Sefcek, J. A., Miller, G. F. and Figueredo, A. J. 2007. “Development and of an 18-item short form of the Ravens Advanced Progressive Matrices (RAPM-18). (Submitted)”.  [Google Scholar]) was used. A significant, positive relationship between K and F (r = .31, p < .001) emerged. Contrary to predictions, no significant relationships were found between “g” and either K or F (r = –.09, p ≥ .05 and r = .11, p ≥ .05, respectively). Though generally contrary to both hypotheses, these results may be explained in relation to antagonistic pleiotropy and a potential failure to derive correct predictions for within-species comparisons directly from the results of between-species comparisons.  相似文献   

17.
US EPA and many state regulatory agency guidance documents recommend below-foundation vapor sampling as a key element of site investigations to determine if vapor migration from underlying soil into buildings is a completed exposure pathway (USEPA, 2002 US EPA (U.S. Environmental Protection Agency). Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soils (Subsurface Vapor Intrusion Guidance). November2002.  [Google Scholar]; WIDHFS, 2003 WIDHFS (Wisconsin Department of Health and Family Services). Chemical Vapor Intrusion and Residential Indoor Air, Guidance for Environmental Consultants and Contractors. June202004. Available at http://dhfs.wisconsin.gov/eh/Air/fs/VI_prof.htm (accessed) [Google Scholar]; San Diego County, 2004 San Diego County Department of Environmental Health. Site Assessment and Mitigation (SAM) Manual. June202004. http://www.sdcounty.ca.gov/deh/lwq/sam/vapor_risk_assessment_2000.html (accessed) [Google Scholar]; PADEP, 2004 PADEP (Pennsylvania Department of Environmental Protection). Land Recycling Program Technical Guidance Manual-Section IV.A.4. June202004. Vapor Intrusion into Buildings from Groundwater and Soil under Act 2 Statewide Health Standard. Document Number 253-0300-100. http://www.dep.state.pa.us/eps/default.asp (accessed) [Google Scholar]). If volatile organic compounds (VOCs) are detected below the building foundation, then VOC migration from the subsurface is assumed to be occurring, and further investigation is needed to determine the extent of the VOC impact. These guidance documents are predicated on the assumption that VOCs detected in below-foundation samples have originated from deeper within the subsurface. However, detection of VOCs in below-foundation vapor samples alone is not sufficient to conclude that the VOCs are migrating from the subsurface upward towards a building. VOCs detected in below-foundation vapor samples can originate from indoor sources, migrating down through the slab by diffusion or advection. Commonly referenced conceptual models for vapor intrusion address VOC migration from the subsurface into buildings but do not consider the potential for VOC migration from buildings into the subsurface (USEPA, 2002 US EPA (U.S. Environmental Protection Agency). Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soils (Subsurface Vapor Intrusion Guidance). November2002.  [Google Scholar]; Johnson and Ettinger, 1991 Johnson, P. C. and Ettinger, R. A. 1991. Heuristic model for the intrusion rate of contaminant vapors into buildings. Environ. Sci. Technol., 25(8): 14451452. [CSA][CROSSREF][Crossref], [Web of Science ®] [Google Scholar]; Parker, 2003 Parker, J. C. 2003. Modeling volatile chemical transport, biodecay, and emission to indoor air. Ground Water Mon. Remed., 23(1): 107120. [CSA][Crossref], [Web of Science ®] [Google Scholar]). The advective and diffusive forces that lead to the migration of VOCs from the subsurface into buildings are equally likely to result in the migration of VOCs from buildings into the subsurface when pressure or concentration gradients support such migration. In this paper we present: i) pressure gradient measurements indicating bi-directional advective flow across building foundations, ii) simple modeling indicating that indoor sources of VOCs may cause subsurface impacts through advection across the building foundation, and iii) field data from a site where indoor sources rather than subsurface contamination were the source of VOCs detected in below-foundation vapor samples.  相似文献   

18.
In this study, we use the measured extent of metal adsorption onto bacterial cells to constrain a linear free energy relationship that allows estimation of unknown stability constants for metal-bacterial surface complexes based on the value of corresponding aqueous metal-acetate stability constants. A previous study (Fein et al., 2001 Fein, J B, Martin, A M and Wightman, P G. 2001. Metal adsorption onto bacterial surface: Development of a predictive approach. Geochim Cosmochim Acta, 65: 42674273. [Crossref], [Web of Science ®] [Google Scholar]) used metal adsorption experiments to constrain a similar relationship, but the experiments were conducted using acid-washed bacteria, and subsequent evidence (Borrok et al., 2004a Borrok, D, Fein, J B, Tischler, M, O'Loughlin, E, Meyer, H, Liss, M and Kemner, K M. 2004a. The effect of acidic solutions and growth conditions on the adsorptive properties of bacterial surfaces. Chem Geol, 209: 107119. [Crossref], [Web of Science ®] [Google Scholar]) shows that the acid-washing step affects the extent of adsorption of a number of metals onto bacterial surfaces. We measured the adsorption of Zn, Ni, Co, Sr, and Nd onto Bacillus subtilis in 0.1 M NaClO4 as a function of pH and metal:bacterial site ratio, using a non-electrostatic discrete four-site model of the bacterial protonation reactions as a basis for the metal adsorption modeling. The adsorption of the divalent cations (Zn, Ni, Co, and Sr) could best be modeled by considering adsorption reactions involving three sites on the bacterial surface; we used a one-site model to account for the Nd data that covered a more restricted pH range. The calculated stability constants for metal-Site 2 bacterial surface complexes are used to re-calibrate the linear free energy relationship previously defined by Fein et al. (2001) Fein, J B, Martin, A M and Wightman, P G. 2001. Metal adsorption onto bacterial surface: Development of a predictive approach. Geochim Cosmochim Acta, 65: 42674273. [Crossref], [Web of Science ®] [Google Scholar]. There is a significant difference between the original and the re-calibrated lines for weakly binding cations such as Sr2 +, but the difference becomes negligible for the stronger-binding cations. Because the linear free energy relationship defined in this study was calibrated from experiments that involved bacteria that were not exposed to acidic conditions, the estimated stability constant values that result from using this relationship are likely to reasonably reflect bacterial adsorption behaviors that occur in realistic geologic settings.  相似文献   

19.
Abstract

A new ichnofossiliferous locality in Salta Province (northwest Argentina) contains an association with numerous irregular spiral traces assigned to Spirodesmos milanai n. isp., in mature sandstones and quartzites with rippled bedding surfaces, rare wavy lamination and cross-bedded stratification. This record of early spiral behavior is interpreted as a primitive grazing method formed on muddy laminae above sand layers, and is related to a feeding strategy of an annelid-type of organism. Associated traces are Cruziana cf. semiplicata, Diplocraterion isp., Monocraterion isp., Rusophycus isp., Skolithos linearis Haldeman and Skolithos magnus Howell. The ichnoassemblage is similar to a shallow-water ichnoassociation from the Permian Ecca Group of South Africa (Mason et al., 1983 Mason, T. R., Stanistreet, I. G. and Tavener-Smith, R. 1983. Spiral trace fossils from the Permian Ecca Group of Zululand. Lethaia, 16: 241247. [Crossref], [Web of Science ®] [Google Scholar]).  相似文献   

20.
A toxicological approach was taken to determine the heavy metal binding capacity of soils. A soil heavy metal binding capacity (SHMBC) methodology was developed and was based on the use of the MetPLATE TM toxicity test kit, a bioassay that is specific for heavy metal toxicity. SHMBC test is based on the heavy metal binding capacity (HMBC) concept that has been considered in the assessment of the metal binding capacity of surface waters (Huang et al., 1999 Huang, F., Bitton, G. and Kong, I.-C. 1999. Determination of the heavy metal binding capacity of aquatic samples using MetPLATE?: a preliminary study. Sci. Total Environ, 234: 139145.  [Google Scholar]) and solid wastes landfill leachates (Ward et al., 2005 Ward, M., Bitton, G. and Townsend, T. 2005. Heavy metal binding capacity (HMBC) of municipal solid waste landfill leachates. Chemosphere, 60: 206215. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]). SHMBC is the ratio of the EC 50 of an added metal in a soil sample divided by the EC 50 of a metal in a reference soil (clean Ottawa sand). A higher SHMBC value indicates higher metal binding to soil and lower bioavailability and potential toxicity to the test bacteria.

Five soils (two sandy soils, two organic soils and a clay soil) were used to determine their binding capacity towards Cu, Zn, and Hg, using the developed SHMBC test. The test measured the ability of the solids to reduce metal bioavailability and toxicity. SHMBC was highest for the clay soil and lowest for the sandy soils. The potential application of this relatively rapid (a few hours) test to predict metal toxicity to terrestrial plants is discussed.  相似文献   


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