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This paper evaluates trills [r] and their palatalized counterparts [rj] from the point of view of markedness. It is argued that [r]s are unmarked sounds in comparison to [rj]s which follows from the examination of the following parameters: (a) frequency of occurrence, (b) articulatory and aerodynamic characteristics, (c) perceptual features, (d) emergence in the process of language acquisition, (e) stability from a diachronic point of view, (f) phonotactic distribution, and (g) implications. Several markedness aspects of [r]s and [rj] are analyzed on the basis of Slavic languages which offer excellent material for the evaluation of trills. Their phonetic characteristics incorporated into phonetically grounded constraints are employed for a phonological OT-analysis of r-palatalization in two selected languages: Polish and Czech.
In this paper it is argued that several typologically unrelated languages share the tendency to avoid voiced sibilant affricates. This tendency is explained by appealing to the phonetic properties of the sounds, and in particular to their aerodynamic characteristics. On the basis of experimental evidence it is shown that conflicting air pressure requirements for maintaining voicing and frication are responsible for the avoidance of voiced affricates. In particular, the air pressure released from the stop phase of the affricate is too high to maintain voicing which in consequence leads to a devoicing of the frication part.
In this paper it is argued that several typologically unrelated languages share the tendency to avoid voiced sibilant affricates. This tendency is explained by appealing to the phonetic properties of the sounds, and in particular to their aerodynamic characteristics. On the basis of experimental evidence it is shown that conflicting air pressure requirements for maintaining voicing and frication are responsible for the avoidance of voiced affricates. In particular, the air pressure released from the stop phase of the affricate is too high to maintain voicing which in consequence leads to a devoicing of the frication part.
This paper evaluates trills [r] and their palatalized counterparts [rj] from the point of view of markedness. It is argued that [r]s are unmarked sounds in comparison to [r ]s which follows from the examination of the following parameters: (a) frequency of occurrence, (b) articulatory and aerodynamic characteristics, (c) perceptual features, (d) emergence in the process of language acquisition, (e) stability from a diachronic point of view, (f) phonotactic distribution, and (g) implications.
Several markedness aspects of [r]s and [rj] are analyzed on the basis of Slavic languages which offer excellent material for the evaluation of trills. Their phonetic characteristics incorporated into phonetically grounded constraints are employed for a phonological OT-analysis of r-palatalization in two selected languages: Polish and Czech.
The present study, based on a typological survey of ca. 70 languages, offers a systematization of consonantal insertions by classifying them into three main types: grammatical, phonetic, and prosodic insertions. The three epenthesis types essentially differ from each other in terms of preferred sounds, domains of application, the role of segmental context, their occurrence cross-linguistically, the extent of variation and phonetic explication.
The present investigation is significantly different from other analyses of consonantal epentheses in the sense that it neither invokes markedness nor diachronic state of the processes under discussion. Instead, it considers the different nature of the epenthetic segments by referring to the representational levels and/or domains which are relevant for their appearance.
(Non)retroflexivity of slavic affricates and its motivation : Evidence from polish and czech <č>
(2005)
The goal of this paper is two-fold. First, it revises the common assumption that the affricate <č> denotes /t͡ʃ/ for all Slavic languages. On the basis of experimental results it is shown that Slavic <č> stands for two sounds: /t͡ʃ/ as e.g. in Czech and /ʈʂ/ as in Polish.
The second goal of the paper is to show that this difference is not accidental but it is motivated by perceptual relations among sibilants. In Polish, /t͡ʃ/ changed to /ʈʂ/ thus lowering its sibilant tonality and creating a better perceptual distance to /tɕ/, whereas in Czech /t͡ʃ/ did not turn to /ʈʂ/, as the former displayed sufficient perceptual distance to the only affricate present in the inventory, namely, the alveolar /t͡s/. Finally, an analysis of Czech and Polish affricate inventories is offered.
In this artiele I reanalyze sibilant inventories of Slavic languages by taking into consideration acoustic. perceptive and phonological evidence. The main goal of this study is to show that perception is an important factor which determines the shape of sibilant inventories. The improvement of perceptual contrast essentially contributes to creating new sibilant inventories by (i) changing the place of articulation of the existing phonemes (ii) merging sibilants that are perceptually very close or (iii) deleting them.
It has also been shown that the symbol s traditionally used in Slavic linguistics corresponds to two sounds in the IP A system: it stands for a postalveolar sibilant (ʃ) in some Slavic languages, as e.g. Bulagarian, Czech, Slovak, some Serbian and Croatian dialects, whereas in others like Polish, Russian, Lower Sorbian it functions as a retroflex (ʂ). This discrepancy is motivated by the fact that ʃ is not optimal in terms of maintaining sufficient perceptual contrast to other sibilants such as s and ɕ. If ʃ occurs together with s (and sʲ) there is a considerable perceptual distance between them but if it occurs with ɕ in an inventory, the distance is much smaller. Therefore, the strategy most languages follow is the change from a postalveolar to a retroflex sibilant.
This summary provides an overview of how new therapies or new aspects of established therapies relate to the latest findings. Neoadjuvant therapy, local therapy, new aspects of systemic therapy, and prognostic and predictive factors are presented. In the neoadjuvant setting, the association between pathological complete response (pCR) and prognosis is still of interest as is the identification of new molecular predictors for new therapies such as CDK4/6 inhibitors. As regards surgical treatment, the target is still to reduce the aggressiveness of surgery. To achieve this, a better understanding particularly of ductal carcinoma in situ is required. With regard to systemic therapy, more data on the best combinations and therapy sequences for existing therapies is available. Finally, the use of prognostic and predictive factors may help to avoid overtreatment and ensure that patients only receive therapies which have been shown to be effective for their specific condition and have fewer side effects.
Chemical pollution is one of the main contributors to the degradation of lotic ecosystems and their biodiversity. Among chemicals driving lotic biodiversity decline are anthropogenic organic micropollutants (AOM), which affect the survival and functioning of freshwater organisms. Continuous exposure of freshwater organisms to AOM leads to adverse effects that sometimes cannot be traced with standard toxicity methods such as standard toxicity testing or biodiversity indices. Among these effects of AOM are selective or mutagenic effects that cause impaired species genetic diversity. Thus, the correlation between different levels of AOM and genetic diversity of species is still poorly understood. However, it can be explored by applying population genetics screening.
In Chapter 1 of this thesis, background information on environmental pollution, genetic screening, and the detection of evolutionary-relevant AOM effects in freshwater organisms are described and the thesis goals are identified. The main goal of the thesis is to study whether AOM exposure occurring in European rivers causes a significant evolutionary footprint in freshwater species and leads to a selection of more tolerant geno-and phenotypes. Therefore, population genetics indices together with high-resolution chemical exposure screening of a widespread indicator invertebrate species, Gammarus pulex (Linnaeus, 1758), living in polluted and pristine European rivers were investigated.
In Chapter 2, the development of a genetic screening method for G. pulex (microsatellites) is described. Due to genetic differentiation and the presence of morphologically cryptic lineages, the available sets of target loci do not enable a reliable population genetic characterization of G. pulex from central Germany. Thus, a novel set of microsatellite loci for a high-precision assessment of population genetic diversity was here applied. Eleven loci were first identified and thereafter amplified in G. pulex from three rivers. The new loci reliably amplified and indicated polymorphisms in the studied amphipods. The amplification resulted in the successful identification of genetically distinct populations of G. pulex from the analyzed rivers. Moreover, the microsatellite loci were amplified in other genetic lineages of G. pulex and another Gammarus species, G. fossarum, promising a broader applicability of the loci in related amphipod species.
In Chapter 3, the effects of AOM on species genetic differentiation and sensitivity to toxic chemicals in a typical central European river with pristine and AOM-polluted sections was investigated. The river’s site-specific concentrations of AOM were assessed by chemical analysis of G. pulex tissue and water samples. To test, whether different levels of AOM in the river select for pollution-dependent genotypes, the genetic structure of G. pulex from the river was analyzed. Finally, the toxicokinetics of and sensitivity to the commonly used insecticide imidacloprid were determined for amphipods sampled at pristine and polluted sections to assess whether various levels of AOM in the river influence sensitivity of G. pulex to imidacloprid. The results indicated that different levels of AOM did not drive genetic divergence of G. pulex within the river but led to an increased sensitivity of exposed amphipods to imidacloprid. The amphipods living in polluted river sections were more sensitive to the insecticide due to chronic exposure to toxic levels of AOM.
In Chapter 4, the relationship between site-specific pollution levels of AOM and genetic diversity parameters of G. pulex was analyzed at the regional scale within six rivers in central Germany. The genetic structure of G. pulex in the studied area was tested for relatedness to the waterway distance between sites. Gammarus pulex genetic diversity parameters, including allelic richness and inbreeding rate, were tested against environmental pollution parameters using linear mixed-effect- and structural-equation models. According to the results, G. pulex genetic diversity parameters were significantly associated with the detected AOM levels. At sites with high concentrations of AOM and toxicity potential G. pulex showed reduced genetic diversity and increased rates of inbreeding. These results suggest that AOM play a major role in shaping the genetic diversity of G. pulex in rivers.
According to the findings presented here, the applied microsatellites can be used to successfully detect changes in genetic patterns in freshwater amphipods facing increased levels of AOM. The findings indicate that levels of AOM representative for European rivers do not lead to the separation of genotypes among G. pulex as the connectivity between sites majorly contributes to species’ genetic structure. However, the chronic exposure to increased levels of toxic AOM leads to a reduction of species genetic diversity and increases the sensitivity of G. pulex to the toxic chemical effects.