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1.
Scott Grimm 《Morphology》2011,21(3-4):515-544
This paper presents a framework which connects case assignment with the semantics of argument realization. Broad notions of agency and affectedness are decomposed into more fine-grained semantic properties, loosely based on Dowty??s Proto-Role theory, but conceived in terms of privative opposition and organized into a lattice. This lattice provides a semantic space of participant properties and supports defining hierarchical relations among participant types, interpreted as semantic prominence, as well as topological relations such as ??closeness??, interpreted as semantic similarity between participant types. Cases are defined as connected regions of this space, relating a given case to a structured set of semantic properties. A case system is represented as a semantic system, which embodies oppositions and contrasts, and operates against the backdrop of the general semantics of argument realization, where one can define notions such as maximal agents and maximal patients and represent generalizations from the research on transitivity. Core case markers (e.g. ergative, accusative) are represented as subspaces of the lattice spreading outwards from the maximal agent and maximal patient nodes of the lattice. Case alternations arise when the subspace of the lattice delimited by a predicate??s entailments for an argument is partitioned by different cases, exemplified with the genitive/accusative alternation in Russian occurring with direct objects of certain intensional predicates. This method also provides a treatment of case polysemy, viz. a single case subsuming multiple uses, by relating the diverse uses at the more abstract semantic level of the case??s region on the lattice, demonstrated with non-canonical uses of the dative. 相似文献
2.
Signed languages exhibit iconicity (resemblance between form and meaning) across their vocabulary, and many non-Indo-European spoken languages feature sizable classes of iconic words known as ideophones. In comparison, Indo-European languages like English and Spanish are believed to be arbitrary outside of a small number of onomatopoeic words. In three experiments with English and two with Spanish, we asked native speakers to rate the iconicity of ~600 words from the English and Spanish MacArthur-Bates Communicative Developmental Inventories. We found that iconicity in the words of both languages varied in a theoretically meaningful way with lexical category. In both languages, adjectives were rated as more iconic than nouns and function words, and corresponding to typological differences between English and Spanish in verb semantics, English verbs were rated as relatively iconic compared to Spanish verbs. We also found that both languages exhibited a negative relationship between iconicity ratings and age of acquisition. Words learned earlier tended to be more iconic, suggesting that iconicity in early vocabulary may aid word learning. Altogether these findings show that iconicity is a graded quality that pervades vocabularies of even the most “arbitrary” spoken languages. The findings provide compelling evidence that iconicity is an important property of all languages, signed and spoken, including Indo-European languages. 相似文献
3.
Alzheimer??s disease (AD) is a serious neurodegenerative disorder and its cause remains largely elusive. In past years, genome-wide association (GWA) studies have provided an effective means for AD research. However, the univariate method that is commonly used in GWA studies cannot effectively detect the biological mechanisms associated with this disease. In this study, we propose a new strategy for the GWA analysis of AD that combines random forests with enrichment analysis. First, backward feature selection using random forests was performed on a GWA dataset of AD patients carrying the apolipoprotein gene (APOE?4) and 1058 susceptible single nucleotide polymorphisms (SNPs) were detected, including several known AD-associated SNPs. Next, the susceptible SNPs were investigated by enrichment analysis and significantly-associated gene functional annotations, such as ??alternative splicing??, ??glycoprotein??, and ??neuron development??, were successfully discovered, indicating that these biological mechanisms play important roles in the development of AD in APOE?4 carriers. These findings may provide insights into the pathogenesis of AD and helpful guidance for further studies. Furthermore, this strategy can easily be modified and applied to GWA studies of other complex diseases. 相似文献
4.
How children acquire knowledge of verb inflection is a long-standing question in language acquisition research. In the present study, we test the predictions of some current constructivist and generativist accounts of the development of verb inflection by focusing on data from two Spanish-speaking children between the ages of 2;0 and 2;6. The constructivist claim that children’s early knowledge of verb inflection is only partially productive is tested by comparing the average number of different inflections per verb in matched samples of child and adult speech. The generativist claim that children’s early use of verb inflection is essentially error-free is tested by investigating the rate at which the children made subject-verb agreement errors in different parts of the present tense paradigm. Our results show: 1) that, although even adults’ use of verb inflection in Spanish tends to look somewhat lexically restricted, both children’s use of verb inflection was significantly less flexible than that of their caregivers, and 2) that, although the rate at which the two children produced subject-verb agreement errors in their speech was very low, this overall error rate hid a consistent pattern of error in which error rates were substantially higher in low frequency than in high frequency contexts, and substantially higher for low frequency than for high frequency verbs. These results undermine the claim that children’s use of verb inflection is fully productive from the earliest observable stages, and are consistent with the constructivist claim that knowledge of verb inflection develops only gradually. 相似文献
5.
Igor Vinogradov 《Morphology》2017,27(1):105-122
Q’eqchi’ (Mayan stock, K’ichean subgroup) is an ergative language; a finite verb form obligatorily carries information on the person and number of the absolutive participant, i.e., the unique argument of an intransitive verb or the direct object of a transitive one. The set of personal absolutive markers includes five morphemes; the third person singular has no overt marker. These morphemes in Modern Q’eqchi’ are prefixes in a finite verbal predication and enclitics in a non-finite predication. In a finite verb form, the place of an absolutive prefix is between the tense-aspect prefix and personal ergative prefix (in a transitive predication) or verb root (in an intransitive one). This paper argues that during Colonial Q’eqchi’ (used in the second half of the 16th century and slightly later) the general structure of a verbal complex was completely different, and all personal absolutive markers were in fact enclitics. They were enclitisized to tense-aspect morphemes that functioned syntactically as main predicates of a complex construction. Further diachronic change consolidated a verbal complex, conditioning the transition to affixation. 相似文献
6.
Pamela Geddes 《Hydrobiologia》2009,628(1):47-66
Studies on spatial subsidies have overwhelmingly addressed their trophic nature. However, certain subsidies might affect recipient
communities beyond the feeding pathway. Terrestrial colored dissolved organic matter (DOM) is such a subsidy providing a carbon
source for bacteria and heterotrophic nanoflagellates which zooplankton can consume (trophic pathway), but also protecting
zooplankton against damaging UV radiation through its color (non-trophic pathway). These mechanisms have been quantified separately,
but few studies have attempted to decouple them and evaluate their effects in the context of subsidies. In this study, I experimentally
isolated the trophic and non-trophic pathways by which DOM (as maple leaf leachate) affects zooplankton, and also addressed
how local food resources (i.e., phytoplankton) could mediate the response of zooplankton to DOM subsidies. Terrestrial subsidies
(DOM) effectively shielded zooplankton against damaging UV radiation. Local resources (i.e., phytoplankton), however, did
not seem to mediate the fitness response of zooplankton to UV radiation. This study also suggested that the carbon in DOM
might be slightly detrimental to zooplankton independent of the UV protection effect. High levels of local resources combined
with carbon subsidies from DOM did not translate into higher zooplankton survival, presumably because of the detrimental effects
of DOM on zooplankton. This study provides further support for the importance of terrestrial subsidies in affecting communities
through non-trophic pathways (UV attenuation) and documents that the trophic pathway might be strongly dependent on subsidy
quality. Further studies on the role of subsidies that include the less documented non-trophic pathways are needed to improve
our mechanistic understanding of how communities and ecosystems respond to spatial subsidies.
Handling editor: D. Bade 相似文献
7.
Larry M. Hyman 《Morphology》2009,19(2):177-206
In this study I present a comparative and historical analysis of “frequentative” Bantu verb-stem reduplication, many of whose variants have been described for a number of Eastern and Southern Bantu languages. While some languages have full-stem compounding, where the stem consists of the verb root plus any and all suffixes, others restrict the reduplicant to two syllables. Two questions are addressed: (i) What was the original nature of reduplication in Proto-Bantu? (ii) What diachronic processes have led to the observed variation? I first consider evidence that the frequentative began as full-stem reduplication, which then became restricted either morphologically (by excluding inflectional and ultimately derivational suffixes) and/or phonologically (by imposing a bisyllabic maximum size constraint). I then turn to the opposite hypothesis and consider evidence and motivations for a conflicting tendency to rebuild full-stem reduplication from the partial reduplicant. I end by attempting to explain why the partial reduplicant is almost always preposed to the fuller base. 相似文献
8.
The fate of dissolved organic matter (DOM) during horizontal subsurface-flow constructed wetlands (HSSF CWs) was examined. In several studies it had been demonstrated that factors such as vegetation and substrates type affected the treatment efficiency of DOM, while very few studies discerned their influence on the transformations of DOM. Thus three pilot-scale HSSF CWs, i.e. reed (Phragmites australis)/gravel bed (W1), hybrid vegetation{cattail (Typha latifolia), bulrush (Scirpus validus), reed}/gravel bed (W2) and reed/hybrid substrates bed (gravel, zeolite, slag) (W3), were designed, and were operated continuously to investigate soluble COD (SCOD) removal and DOM transformations affected by vegetation and substrate type, and to explore the correlation between SCOD and biodiversity. The results showed that cattail and bulrush contributed to higher SCOD removal than common reed, and that gravel, zeolite and slag did not show significant influence on SCOD removal. The composition of the dissolved organic carbon (DOC) could undergo a considerable shift in composition due to metabolism and senescence from plant and microorganism. Nonlabile aromatic hydrocarbons and alkyl hydrocarbons in the effluent were a significant portion compared with labile alcoholic and alkene in the influent. It was also observed that the type of vegetation and substrate had great influence on the structure of bacteria, and the Shannon-Wiener Index increased linearly with the decrease of SCOD concentration along water flow in W2 and W3 (R2=0.96). 相似文献
9.
em. Univ.-Prof. Dr. G. Utermann 《Medizinische Genetik》2011,23(1):7-14
A better understanding of complex diseases and their genetics has been gained by investigating genetic disorders of lipoprotein metabolism. This has resulted in the development of ddrugs to prevent atherosclerosis, the most frequent cause of death in industrialized countries. Thus, analysis of familial hypercholesterinemia (FH), the most frequent cause of which are mutations on the LDLR gene, has contributed to the development of HMG-CoA reductase inhibitors (statins). Meanwhile, in genome-wide association studies (GWAS), variants in over 90 genes have been found to influence the concentration of plasma lipids. However, these explain only a small fraction of the genetic variance of the traits. Taking the classical polymorphism of Apo-E as an example, it is discussed that one possible reason for the ??missing heritability?? may be the selection of the SNPs on the arrays used in the GWAS. Further, this polymorphism demonstrates how interactions may mask a connection between a genotype and a disease. Genetic studies based on the principle of ??Mendelian randomization?? have established the causal role of a high Lp(a) concentration as a risk factor for coronary heart disease (CHD). For patients with end-stage renal disease, however, a polymorphism (KIV-2 CNV) is a better predictor for CHD than Lp(a) concentration. 相似文献
10.
C. E. L. Thompson B. Silburn M. E. Williams T. Hull D. Sivyer L. O. Amoudry S. Widdicombe J. Ingels G. Carnovale C. L. McNeill R. Hale C. Laguionie Marchais N. Hicks H. E. K. Smith J. K. Klar J. G. Hiddink J. Kowalik V. Kitidis S. Reynolds E. M. S. Woodward K. Tait W. B. Homoky S. Kröger S. Bolam J. A. Godbold J. Aldridge D. J. Mayor N. M. A. Benoist B. J. Bett K. J. Morris E. R. Parker H. A. Ruhl P. J. Statham M. Solan 《Biogeochemistry》2017,132(1-2):1-22
Headwater streams influence the biogeochemical characteristics of large rivers and play important roles in regional and global carbon budgets. The combined effects of seasonality and land use change on the biogeochemistry of headwater streams, however, are not well understood. In this study we assessed the influence of catchment land use and seasonality on the composition of dissolved organic matter (DOM) and ecosystem metabolism in headwater streams of a Kenyan river. Fifty sites in 34 streams draining a gradient of catchment land use from 100% natural forest to 100% agriculture were sampled to determine temporal and spatial variation in DOM composition. Gross primary production (GPP) and ecosystem respiration (ER) were determined in 10 streams draining primarily forest or agricultural catchments. Absorbance and fluorescence spectrophotometry of DOM reflected notable shifts in composition along the land use gradient and with season. During the dry season, forest streams contained higher molecular weight and terrestrially derived DOM, whereas agricultural streams were dominated by autochthonous production and low molecular weight DOM. During the rainy season, aromaticity and high molecular weight DOM increased in agricultural streams, coinciding with seasonal erosion of soils and inputs of organic matter from farmlands. Most of the streams were heterotrophic. However, GPP and ER were generally greater in agricultural streams, driven by higher dissolved nutrient (mainly TDN) concentrations, light availability (open canopy) and temperature compared with forest streams. There were correlations between freshly and autochthonously produced DOM, GPP and ER during both the dry and wet seasons. This is one of the few studies to link land-use with organic carbon dynamics and DOM composition. Measures of ecosystem metabolism in these streams help to affirm the role of tropical streams and rivers as important components of the global carbon cycle and demonstrate that even semi-intensive, smallholder agriculture can have measurable effects on riverine ecosystem functioning. 相似文献
11.
The research study investigated the possible associations among science and biology teachers?? knowledge and belief variables concerning teaching evolution in science and biology classes. Specifically, this study examined how a set of variables including teachers?? understanding of evolution and nature of science (NOS) is related to the set of variables including teachers?? acceptance of evolution and perceptions of teaching evolution (i.e., perceptions of the necessity of addressing evolution in their classrooms, perceptions of the factors that impede addressing evolution in their classrooms, and personal science teaching efficacy beliefs regarding evolution). Data were collected from science and biology teachers through administration of Evolution Content Knowledge Test, Measure of Acceptance of the Theory of Evolution, Nature of Science as Argument Questionnaire and Teachers?? Perceptions of Teaching Evolution Scale. Canonical correlation analysis findings suggested that teachers who had thorough understanding of evolution and NOS were likely to both accept the scientific validity of evolution and believe the necessity of addressing evolution in the classrooms. On the other hand, teachers with thorough understanding of evolution and NOS did not necessarily believe that they have a stronger sense of self-efficacy beliefs regarding teaching evolution and that there are fewer obstacles to addressing evolution in the classroom. The research is significant in that it provides empirical evidence clarifying the interactions between teachers?? understanding and beliefs in teaching evolution. Implications for science teacher education are discussed. 相似文献
12.
KAREN E. WEBB 《American anthropologist》1977,79(1):42-49
Bradfield has pointed out that little is known of the relationship between grammatical forms and the "values and attitudes associated with economic activity." This paper reports on a current research project which is exploring the relationship between possession and transitivity and property-based societies. The author posits an evolutionary sequence of possessive verb development similar to the evolutionary development of color terms shown in the work of Berlin and Kay . [language and culture, cultural evolution, ethnolinguistics (semantics), possession (grammatical), cross-cultural study] 相似文献
13.
Taylor LN Baker DW Wood CM McDonald DG 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2002,133(1-2):111-124
The main objective of this study was to characterize the individual effects of water chemistry (Ca(2+), Na(+), dissolved organic matter (DOM), pH, alkalinity) on the rapid binding of copper to the gill surface of rainbow trout using an in vitro gill binding assay. In this assay, individual gill arches were exposed for 5 min to (64)Cu labelled copper solutions ranging from 0.02 to 0.16 microM in water chemistries reflecting the full range of fresh water values for the Great Lakes. The gills displayed saturable Cu binding within this Cu range but gill-Cu binding was completely unaffected over the full range of calcium, sodium and alkalinity concentrations used. Only low pH (pH 4.0) and commercial DOM (Aldrich humic acid at > or =3 mgC/l) altered copper binding to rainbow trout gills in vitro. These findings were consistent with the results of geochemical modelling of our water chemistry (using MINEQL+, Version 4.5) which showed that H(+) and DOM affected the free cupric ion concentration. However, DOM (up to 80 mgC/l) was only able to reduce Cu on the gills by 50%. We hypothesize that in the range of 0.02-0.16 microM Cu there are two high affinity Cu binding sites on the gills, one having a substantially higher affinity for copper than DOM. The absence of a calcium effect on gill copper binding was in accord with in vivo evidence that calcium primarily acts to alter the physiology of the gill binding sites through acclimatory processes, rather than through competitive interactions. It was a surprise that water chemistry parameters influence rapid gill-metal binding in a manner different to their influence on acute toxicity and different from the effects on long-term binding reported in other studies. Currently, the biotic ligand model uses the rapid increase of gill copper (believed to reflect binding to the physiologically active receptor sites) to model gill binding characteristics. The distinction between rapid surface binding and metal uptake obviously plays an important role in determining the toxic effects of copper, especially when regulators need to predict the modifying effects of water chemistry. 相似文献
14.
15.
K. P. Skandhan B. Sumangala S. Amith K. P. S. Avni 《Biological trace element research》2011,141(1-3):91-95
Recently, technological advancement helped to improve our knowledge on trace elements in human male reproductive organs and its secretion, semen. In this study, employing energy dispersive x-ray analysis facilities on electron microscope, presence of different elements in human male reproductive organs-??testis, epididymis, caput, corpus and cauda, prostate gland, seminal vesicle, Cowper??s gland and vas deferens??seminal plasma and spermatozoa pellet was studied. Several elements were observed. Gold was one among them that was present in seminal plasma and spermatozoa. It was also present in epididymis caput. Authors consider epididymis caput as the source of gold in semen. 相似文献
16.
Past studies have suggested that the concentration and quality of dissolved organic matter (DOM) may influence microbial community structure. In this study, we cross-inoculated the bacterial communities from two streams and a dystrophic lake that varied in DOM concentration and chemistry, to yield nine fully crossed treatments. We measured dissolved organic carbon (DOC) concentration and heterotrophic microbial community productivity throughout a 72-h incubation period, characterized DOM quality by molecular weight, and determined microbial community structure at the initial and final time points. Our results indicate that all bacterial inoculate sources had similar effects upon DOC concentration and DOM quality, regardless of the DOM source. These effects included an overall decrease in DOM M
W and an initial period of DOC concentration variability between 0-24h. In contrast, microbial communities and their metabolic rates converged to profiles that reflected the DOM source upon which they were growing, regardless of the initial bacterial inoculation. The one exception was that the bacterial community from the low-concentration and low-molecular-weight DOM source exhibited a greater denaturing gradient gel electrophoresis (DGGE) band richness when grown in its own DOM source than when grown in the highest concentration and molecular weight DOM source. This treatment also exhibited a higher rate of productivity. In general, our data suggest that microbial communities are selected by the DOM sources to which they are exposed. A microbial community will utilize the low-molecular-weight (or labile) DOM sources as well as parts of the high-molecular-weight (refractory) DOM, until a community develops that can efficiently metabolize the more abundant high-molecular-weight source. This experiment examines some of the complex interactions between microbial community selection and the combined factors of DOM quality and concentration. Our data suggest that the roles of aerobic aquatic heterotrophic bacteria in carbon cycling, as well as the importance of high-molecular-weight DOM as a carbon source, may be more complex than is conventionally recognized. 相似文献
17.
溶解性有机质对土壤中有机污染物环境行为的影响 总被引:28,自引:4,他引:28
土壤中溶解性有机质(DOM)是生物活性和物理化学反应活性都很活跃的有机组分,主要通过疏水吸附、分配、氢键、电荷转移、共价键、范德华力等多种作用与有机污染物结合,提高溶液中有机污染物的溶解度,改变土壤中有机污染物的吸附-解吸、迁移-转化等环境行为.DOM对有机污染物的吸附-解吸、迁移-转化过程的影响有双重性:一方面,DOM与有机污染物在土壤表面的共吸附可增加土壤对有机污染物的吸附容量,促进有机污染物在土壤中的吸持;另一方面,DOM对有机污染物的增溶作用,有利于土壤中有机污染物的解吸,提高移动性.作为光敏剂,DOM能提高土壤中有机物的光解反应速率.在一定条件下,DOM也可影响土壤中有机污染物的水解过程.DOM对土壤中有机污染物环境行为的影响与DOM和有机污染物的性质及其相互作用的介质条件密切相关. 相似文献
18.
The effects of dissolved organic matter (DOM), water soluble organic matter derived from sewage sludge, on the sorption of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-trazine) by soils were studied using a batch equilibrium technique. Six paddy soils, chosen so as to have different organic carbon contents, were experimented in this investigation. Atrazine sorption isotherms on soils were described by the linear equation, and the distribution coefficients without DOM (Kd) or with DOM (Kd*) were obtained. Generally, the values of Kd*/Kd initially insoil-solution system form. Critical concentrations of DOM (DOMnp) were obtained where the value of Kd* was equal to Kd. The presence of DOM with concentrations lower than DOMnp promoted atrazine sorption on soils (Kd* > Kd), whereas the presence of DOM with concentrations higher than DOMnp tended to inhibit atrazine sorption (Kd* < Kd). Interestingly, DOMnp for tested soils was negatively correlated to the soil organic carbon content, and the maximum of Kd*/Kd (i.e.Kmax) correlated positively with the maximum of DOM sorption on soil (Xmax). Further investigations showed that the presence of hydrophobic fraction of DOM evidently promoted the atrazine sorption on soils, whereas the presence of hydrophilic DOM fraction obviously tended to inhibit the atrazine sorption. Interactions of soil surfaces with DOM and its fractions were suggested to be the major processes determining atrazine sorption on soils. The results of this work provide a reference to the agricultural use of organic amendment such as sewage sludge for improving the availability of atrazine in soils. 相似文献
19.
Seasonal response of stream biofilm communities to dissolved organic matter and nutrient enrichments
Dissolved organic matter (DOM) and inorganic nutrients may affect microbial communities in streams, but little is known about the impact of these factors on specific taxa within bacterial assemblages in biofilms. In this study, nutrient diffusing artificial substrates were used to examine bacterial responses to DOM (i.e., glucose, leaf leachate, and algal exudates) and inorganic nutrients (nitrate and phosphate singly and in combination). Artificial substrates were deployed for five seasons, from summer 2002 to summer 2003, in a northeastern Ohio stream. Differences were observed in the responses of bacterial taxa examined to various DOM and inorganic nutrient treatments, and the response patterns varied seasonally, indicating that resources that limit the bacterial communities change over time. Overall, the greatest responses were to labile, low-molecular-weight DOM (i.e., glucose) at times when chlorophyll a concentrations were low due to scouring during significant storm events. Different types of DOM and inorganic nutrients induced various responses among bacterial taxa in the biofilms examined, and these responses would not have been apparent if they were examined at the community level or if seasonal changes were not taken into account. 相似文献
20.
Stream bacteria may be influenced by the composition and availability of dissolved organic matter (DOM) and inorganic nutrients, but knowledge about how individual phylogenetic groups in biofilm are affected is still limited. In this study, the influence of DOM and inorganic nutrients on stream biofilm bacteria was examined. Biofilms were developed on artificial substrates (unglazed ceramic tiles) for 21 days in a northeastern Ohio (USA) stream for five consecutive seasons. Then, the developed biofilm assemblages were exposed, in the laboratory, to DOM (glucose, leaf leachate, and algal exudates) and inorganic nutrients (nitrate, phosphate, and nitrate and phosphate in combination) amendments for 6 days. Bacterial numbers in the biofilms were generally higher in response to the DOM treatments than to the inorganic nutrient treatments. There were also apparent seasonal variations in the response patterns of the individual bacterial taxa to the nutrient treatments; an indication that limiting resources to bacteria in stream biofilms may change over time. Overall, in contrast to the other treatments, bacterial abundance was generally highest in response to the low-molecular-weight DOM (i.e., glucose) treatment. These results further suggest that there are interactions among the different bacterial groups in biofilms that are impacted by the associated nutrient dynamics among seasons in stream ecosystems. 相似文献