bluuebunny/crossref_metadata_2025 huggingface dataset:
Dopamine D1/D5 receptor modulation of excitatory synaptic inputs to layer V prefrontal cortex neurons
Authors: Seamans Jeremy K. , Durstewitz Daniel , Christie Brian R. , Stevens Charles F. , Sejnowski Terrence J.
Published: July 2012

Dopamine acts mainly through the D1/D5 receptor in the prefrontal
cortex (PFC) to modulate neural activity and behaviors associated with
working memory. To understand the mechanism of this effect, we examined
the modulation of excitatory synaptic inputs onto layer V PFC pyramidal
neurons by D1/D5 receptor stimulation. D1/D5 agonists increased the
size of
N-
methyl-
d
-aspartate (NMDA)
component of excitatory postsynaptic currents (EPSCs) through a
postsynaptic mechanism. In contrast, D1/D5 agonists caused a slight
reduction in the size of the non-NMDA component of EPSCs through a
small decrease in release probability. With 20 Hz synaptic trains, we
found that the D1/D5 agonists increased depolarization of summating
the NMDA component of excitatory postsynaptic potential (EPSP). By
increasing the NMDA component of EPSCs, yet slightly reducing release,
D1/D5 receptor activation selectively enhanced sustained synaptic
inputs and equalized the sizes of EPSPs in a 20-Hz train.
Multiple neural correlates of detection in the human brain
Authors: Shulman Gordon L. , Ollinger John M. , Linenweber Martin , Petersen Steven E. , Corbetta Maurizio
Published: July 2012

We used event-related functional MRI to examine the neural
consequences of detecting the presence or absence of a stimulus.
Subjects detected a brief interval of coherent motion embedded in
dynamic noise that was presented throughout a test period. Several
brain regions, including V1/V2, middle temporal complex (MT+), left
intraparietal cortex, and the frontal eye field, were activated at the
onset of the dynamic noise, irrespective of whether a coherent motion
target was presented early or late in the test period, or not at all.
These regions, many of which were motion sensitive, were likely
involved in searching for and detecting the target. The blood
oxygenation level-dependent signal in these regions was higher in
trials in which a target was detected than in trials in which it was
missed or not presented, indicating that these regions were modulated
by detection. Moreover, the blood oxygenation leveldependent signal in
these regions decayed quickly once a target was detected, even though
the dynamic noise continued to be displayed, indicating that they were
shut down after detection. Therefore, detection-related modulations
occurred in the same regions that accumulate target information over
time, in agreement with current psychological and neural models of
detection. Many other regions, however, including areas in prefrontal
cortex and anterior cingulate, were not involved in searching for a
target. In these regions, activation began early in the test period
when an early target was detected but began late in the test period
when a late target was detected or when a response was correctly
withheld in the absence of a motion target. The signal in these regions
was therefore triggered by a discrete event during the test interval
that was related to presence–absence detection.
Action potential propagation in mitral cell lateral dendrites is decremental and controls recurrent and lateral inhibition in the mammalian olfactory bulb
Authors: Margrie Troy W. , Sakmann Bert , Urban Nathaniel N.
Published: July 2012

In the mammalian main olfactory bulb (MOB), the release of
glutamate from lateral dendrites of mitral cells onto the dendrites of
granule cells evokes recurrent and lateral inhibition of mitral cell
activity. Whole-cell voltage recordings in the mouse MOB
in
vivo
and
in vitro
show that recurrent and
lateral inhibition together control the number, duration, and onset of
odor-evoked action potential (AP) firing in mitral cells. APs in mitral
cells propagate into the lateral dendrites and evoke a transient
increase in dendritic calcium concentration ([Ca
2+
]),
which is decremental with distance from the soma, and increases with AP
number. These results suggest that the extent of AP propagation in
lateral dendrites of mitral cells, along with the concomitant dendritic
Ca
2+
transient, controls the amplitude of lateral and
recurrent inhibition and thus is a critical determinant of
odor-specific AP patterns in the MOB.
Mechanisms governing dendritic γ-aminobutyric acid (GABA) release in the rat olfactory bulb
Authors: Isaacson Jeffry S.
Published: July 2012

In the olfactory bulb, synaptic transmission between dendrites
plays an important role in the processing of olfactory information.
Glutamate released from the dendrites of principal mitral cells excites
the dendritic spines of granule cells, which in turn release
γ-aminobutyric acid (GABA) back onto mitral cell dendrites. Slow
N
-methyl-
d
-aspartate (NMDA) receptors on
granule dendrites are particularly effective in driving this reciprocal
dendrodendritic inhibition (DDI), raising the possibility that calcium
influx through NMDA receptors may trigger GABA exocytosis directly. In
this study, I show that NMDA receptor activation is not an absolute
requirement and that DDI can be evoked solely by
α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors
when granule cell excitability is increased or under conditions that
slow AMPA receptor kinetics. In physiological extracellular
Mg
2+
, DDI elicited by photolysis of caged calcium in mitral
dendrites is blocked by cadmium and toxins to N- and P/Q-type
voltage-gated calcium channels. DDI is largely unaffected after granule
dendrites have been loaded with the slow calcium chelator EGTA,
suggesting a tight coupling between the site of calcium influx and the
release machinery governing GABA exocytosis. These results indicate
that voltage-gated calcium channels play an essential role in dendritic
GABA release during reciprocal feedback inhibition in the olfactory
bulb.
The biological lifetime of nitric oxide: Implications for the perivascular dynamics of NO and O
2
Authors: Thomas Douglas D. , Liu Xiaoping , Kantrow Stephen P. , Lancaster Jack R.
Published: July 2012

Endothelial nitric oxide (nitrogen monoxide) is synthesized at the
intravascular/extravascular interface. We previously have reported
the intravascular half-life of NO, as a result of consumption by
erythrocytes, as approximately 2 ms. We report here studies designed to
estimate the lifetime of NO in the parenchymal (extravascular) tissue
and describe the implications of these results for the distribution of
NO and oxygen concentration gradients away from the blood vessel. The
rate of consumption of NO by parenchymal cells (hepatocytes) linearly
depends on both NO and O
2
concentration. We estimate that
the extravascular half-life of NO will range from 0.09 to >
2 s, depending on O
2
concentration and thus distance
from the vessel. Computer modeling reveals that this phenomenon,
coupled with reversible NO inhibition of cellular mitochondrial oxygen
consumption, substantially extends the zone of adequate tissue cellular
oxygenation away from the blood vessel, with an especially dramatic
effect during conditions of increased tissue work (oxygen consumption).
This represents a second action of NO, in addition to vasodilation, in
enhancing tissue cellular respiration and provides a possible
physiological function for the known reversible inhibition of
mitochondrial respiration by low concentrations of NO.
Metabolic engineering of plant alkaloid biosynthesis
Authors: Sato Fumihiko , Hashimoto Takashi , Hachiya Akira , Tamura Ken-ichi , Choi Kum-Boo , Morishige Takashi , Fujimoto Hideki , Yamada Yasuyuki
Published: July 2012

Plant alkaloids, one of the largest groups of natural
products, provide many pharmacologically active compounds. Several
genes in the biosynthetic pathways for scopolamine, nicotine, and
berberine have been cloned, making the metabolic engineering of these
alkaloids possible. Expression of two branching-point enzymes was
engineered: putrescine
N
-methyltransferase (PMT) in
transgenic plants of
Atropa belladonna
and
Nicotiana sylvestris
and (
S
)-scoulerine
9-
O
-methyltransferase (SMT) in cultured cells of
Coptis japonica
and
Eschscholzia
californica
. Overexpression of PMT increased the nicotine
content in
N. sylvestris
, whereas suppression of
endogenous PMT activity severely decreased the nicotine
content and induced abnormal morphologies. Ectopic expression of SMT
caused the accumulation of benzylisoquinoline alkaloids in
E.
californica
. The prospects and limitations of engineering plant
alkaloid metabolism are discussed.
Negative regulation of defense responses in plants by a conserved MAPKK kinase
Authors: Frye Catherine A. , Tang Dingzhong , Innes Roger W.
Published: July 2012

The
enhanced disease resistance 1
(
edr1
) mutation of
Arabidopsis
confers
resistance to powdery mildew disease caused by the fungus
Erysiphe cichoracearum.
Resistance mediated by the
edr1
mutation is correlated with induction of several
defense responses, including host cell death. Double mutant analysis
revealed that all
edr1-
associated phenotypes are
suppressed by mutations that block salicylic acid (SA) perception
(
nim1
) or reduce SA production (
pad4
and
eds1
). The
NahG
transgene, which lowers
endogenous SA levels, also suppressed
edr1.
In contrast, the
ein2
mutation did not suppress
edr1-
mediated resistance and associated phenotypes,
indicating that ethylene and jasmonic acid-induced responses are not
required for
edr1
resistance. The
EDR1
gene was isolated by positional cloning and was found to encode a
putative MAP kinase kinase kinase similar to CTR1, a negative regulator
of ethylene responses in
Arabidopsis
. Taken together,
these data suggest that EDR1 functions at the top of a MAP kinase
cascade that negatively regulates SA-inducible defense responses.
Putative orthologs of EDR1 are present in monocots such as rice and
barley, indicating that EDR1 may regulate defense responses in a wide
range of crop species.
Antisense-induced exon skipping and synthesis of dystrophin in the
mdx
mouse
Authors: Mann Christopher J. , Honeyman Kaite , Cheng Andy J. , Ly Tina , Lloyd Frances , Fletcher Sue , Morgan Jennifer E. , Partridge Terry A. , Wilton Stephen D.
Published: July 2012

Duchenne muscular dystrophy (DMD) is a severe muscle wasting
disease arising from defects in the dystrophin gene, typically nonsense
or frameshift mutations, that preclude the synthesis of a functional
protein. A milder, allelic version of the disease, Becker muscular
dystrophy, generally arises from in-frame deletions that allow
synthesis of a shorter but still semifunctional protein. Therapies to
introduce functional dystrophin into dystrophic tissue through either
cell or gene replacement have not been successful to date. We report an
alternative approach where 2′-
O
-methyl antisense
oligoribonucleotides have been used to modify processing of the
dystrophin pre-mRNA in the
mdx
mouse model of DMD. By
targeting 2′-
O
-methyl antisense oligoribonucleotides to
block motifs involved in normal dystrophin pre-mRNA splicing, we
induced excision of exon 23, and the
mdx
nonsense
mutation, without disrupting the reading frame. Exon 23 skipping was
first optimized
in vitro
in transfected
H-2K
b
-tsA58 mdx
myoblasts and
then induced
in vivo
. Immunohistochemical staining
demonstrated the synthesis and correct subsarcolemmal localization of
dystrophin and γ-sarcoglycan in the
mdx
mouse after
intramuscular delivery of antisense oligoribonucleotide:liposome
complexes. This approach should reduce the severity of DMD by allowing
a dystrophic gene transcript to be modified, such that it can be
translated into a Becker-dystrophin-like protein.
Tailoringin vitroevolution for protein affinity or stability
Authors: Jermutus Lutz , Honegger Annemarie , Schwesinger Falk , Hanes Jozef , Plückthun Andreas
Published: July 2012

We describe a rapid and general technology working entirelyin vitroto evolve either the affinity or the stability of ligand-binding proteins, depending on the chosen selection pressure. Tailoredin vitroselection strategies based on ribosome display were combined within vitrodiversification by DNA shuffling to evolve either the off-rate or thermodynamic stability of single-chain Fv antibody fragments (scFvs). To demonstrate the potential of this method, we chose to optimize two proteins already possessing favorable properties. A scFv with an initial affinity of 1.1 nM (koffat 4°C of 10−4s−1) was improved 30-fold by the use of off-rate selections over a period of several days. As a second example, a generic selection strategy for improved stability exploited the property of ribosome display that the conditions can be altered under which the folding of the displayed protein occurs. We used decreasing redox potentials in the selection step to select for molecules stable in the absence of disulfide bonds. They could be functionally expressed in the reducing cytoplasm, and, when allowed to form disulfides again, their stability had increased to 54 kJ/mol from an initial value of 24 kJ/mol. Sequencing revealed that the evolved mutant proteins had used different strategies of residue changes to adapt to the selection pressure. Therefore, by a combination of randomization and appropriate selection strategies, anin vitroevolution of protein properties in a predictable direction is possible.
Purification, priming, and catalytic acylation of carrier protein domains in the polyketide synthase and nonribosomal peptidyl synthetase modules of the HMWP1 subunit of yersiniabactin synthetase
Authors: Suo Zucai , Tseng Claire C. , Walsh Christopher T.
Published: July 2012

The 207-kDa polyketide synthase (PKS) module (residues 1–1895) and
the 143-kDa nonribosomal peptidyl synthetase (NRPS) module (1896–3163)
of the 350-kDa HMWP1 subunit of yersiniabactin synthetase have been
expressed in and purified from
Escherichia coli
in
soluble forms to characterize the acyl carrier protein (ACP) domain of
the PKS module and the homologous peptidyl carrier protein
(PCP
3
) domain of the NRPS module. The apo-ACP and PCP
domains could be selectively posttranslationally primed by the
E. coli
ACPS and EntD phosphopantetheinyl transferases
(PPTases), respectively, whereas the
Bacillus subtilis
PPTase Sfp primed both carrier protein domains
in vitro
or during
in vivo
coexpression. The holo-NRPS module but
not the holo-PKS module was then selectively aminoacylated with
cysteine by the adenylation domain embedded in the HMWP2 subunit of
yersiniabactin synthetase, acting in
trans
. When the
acyltransferase (AT) domain of HMWP1 was analyzed for its ability to
malonylate the holo carrier protein domains, in
cis
acylation was first detected. Then, in
trans
malonylation of the excised holo-ACP or holo-PCP
3
–TE
fragments by HMWP1 showed both were malonylated with a 3:1 catalytic
efficiency ratio, showing a promiscuity to the AT domain.
Is the heritage language like a second language?
Authors: Montrul Silvina A.
Published: July 2012

Many heritage speakers (bilinguals in a minority language context) turn to the second language (L2) classroom to expand their knowledge of the heritage language. Critical questions arise as to how their linguistic knowledge compares to that of post puberty L2 learners. Focusing on recent experimental research on grammatical domains typically affected in both L2 learners and heritage speakers, this article addresses whether exposure to the family language since birth even under reduced input conditions leads to more native-like linguistic knowledge in heritage speakers as opposed to L2 learners with a later age of acquisition of the language, how differences in input and language learning experience determine the behavioral manifestations of linguistic knowledge, and whether formal instruction in the classroom is beneficial to heritage speakers. I argue that the extension of theoretical frameworks and methodologies from SLA has significantly advanced the field of heritage language acquisition, but deeper understanding of these speakers will also need more fruitful integration of the psycholinguistic and sociolinguistic factors that contribute to the acquisition and maintenance of heritage languages.
A contextual perspective on oral L2 fluency
Authors: Schoonjans Els
Published: July 2012

This paper reports on a study investigating the impact of differences in the learning context on oral L2 fluency outcomes. The study specifically focuses on the effect of different levels of L1 and L2 prominence (as determined by their status, functions roles and domains of use) in the extracurricular context on the speed, breakdown and repair fluency of the L2 speech of German learners of English (ages 8–14). Controlled variation of L1 and L2 prominence is observed across 4 different authentic language learning contexts. The results demonstrate an effect of different levels of L2 prominence on L2 speed and breakdown fluency and grant support to a gradient operationalization of language prominence. We further suggest that L1 prominence is a relevant factor in the operationalization of context. The different dimensions of fluency (i.e., speed, breakdown and repair fluency) are affected differently by elements in the learning context, which confirms the multilayered approach to the construct.
Second language effects on ambiguity resolution in the first language
Authors: Brien Christie , Sabourin Laura L.
Published: July 2012

The processing of homonyms is complex considering homonyms have many lexical properties. For instance, train contains semantic (a locomotive/to instruct) and syntactic (noun/verb) properties, each affecting interpretation. Previous studies find homonym processing influenced by lexical frequency (Duffy et al. 1988) as well as syntactic and semantic context (Folk & Morris 2003; Swinney 1979; Tanenhaus et al. 1979). This cross-modal lexical-decision study investigates second language (L2) effects on homonym processing in the first language (L1). Participants were monolingual English speakers and Canadian English/French bilinguals who acquired L2 French at distinct periods. The early bilinguals revealed no significant differences compared to monolinguals (p = .219) supporting the Reordered Access Model (Duffy et al. 1988). However, the late bilinguals revealed longer reaction times, syntactic priming effects (p < .001), and lexical frequency effects (p < .001), suggesting a heightened sensitivity to surface cues influencing homonym processing in the L1 due to a newly-acquired L2 (Cook 2003).
Clause relationships in spoken and written English
Authors: Greenbaum Sidney , Nelson Gerald
Published: July 2012

There are opposing views on whether speech or writing is more complex syntactically. We investigated the complexity of clause relationships in a range of spoken and written text categories: spontaneous conversations, broadcast discussions, unscripted monologues, personal handwritten letters, academic writing, and non-academic writing. Conversations proved to be the most distinctive category. It had the highest percentage of simple clauses and the lowest percentage of both subordination and coordination. For all the other categories there is not a sharp distinction between speech and writing in any of the measures that were applied.
L’évidence des anglicismes dans les discours journalistiques français
Authors: Bernard-Béziade Mélanie , Attali Michaël
Published: July 2012

Given their internationalization and their dependence on the International Olympic Committee (IOC), the Olympic Games provide good evidence of linguistic usages in the field of sport and constitute a preferred domain for the lexical study of anglicisms, since, although French is one of the official languages of the Olympic Games, the discourse of sport generally relies on English. Representative of this tendency, the work of journalists examined here displays a variety of lexical strategies. A linguistic analysis of two Olympic sports, athletics and swimming, seems to show that sport is inextricably linked to a particular structural discourse whose tenor is regularly conveyed by journalists. Beyond linguistic barriers, it seems that the perceived nature of sport leads to the privileging of anglicisms which command unquestioned acceptance much as the values of sport do — themselves generally taken for granted without discussion.
Esperanto and minority languages
Authors: Goro Christoph Kimura
Published: July 2012

Esperanto seems to share several basic characteristics with minority languages. Tendencies regarded as basic features of the Esperanto community, such as voluntariness, non-ethnic composition, non-territorial distribution or the “internal idea” can be observed also among minority languages. It can thus be argued that phenomena and tendencies that can be observed in the case of Esperanto are even clearer or more pronounced in the case of the (other) minority languages, and vice versa. The two can function as “mirrors” for one another. Not only their aims to promote multilingualism, but also the current opportunities and problems that these strikingly similar linguistic communities face, appear to make cooperation useful and open new prospects for comparative research.
Methodological questions about translation research
Authors: Campbell Stuart , Wakim Berta
Published: July 2012

Research on the mental processes of written translation has benefited less from the findings of psycholinguistic and cognitive research than interpreting research has. This has left translation research relatively impoverished in the theoretical grounding of research methodology. While the performance speed of interpreting seems to make interpreting research closer to bilingual speech research, the shared features of interpreting and translation suggest that they are points on a continuum rather than discrete production modes. A Translation-Interpreting Continuum is proposed, which allows various production modes to be described in terms of psycholinguistic notions, and which includes a language development dimension to account for second language production. The Continuum allows some very basic questions about translation research methodology to be answered, and opens up the opportunity for a better integration of translation and interpreting research.
Foreign names into native tongues
Authors: Li Wen-Chao Chris
Published: July 2012

The transfer of sound from one language into another is not a uniform process, but rather, takes different forms depending on the orthographies and phonological properties of source and target languages, the less common of which involve processes significantly different from transliteration between European phonetic scripts. This paper pools techniques commonly used in loanword phonology and second language acquisition to illustrate complications that arise when translating names from English into languages such as Japanese and Chinese, which differ significantly from the source language in syllable structure and orthographic convention. Competing strategies of adaptation and accommodation are placed in the context of lexical retrieval and compared with experimental studies of nativization in interlanguage. It will be shown that for names to be perceived as similar-sounding across language boundaries, it would be desirable to look beyond segmental equivalence and consider stress, syllable count and other suprasegmental factors that play a greater role in phonological memory.
A corpus-based study of the verbobservarin English-Spanish translations of biomedical research articles
Authors: Williams Ian A.
Published: July 2012

This paper describes an empirical contextual study of the English verbs and syntactic resources translated byobservarin an extensive corpus of biomedical research articles. Quantitative analysis showed that the frequency ofobservarwas significantly higher in the Spanish translations than in the comparable Spanish language original articles (360 vs. 162 instances;P< 0·001). Qualitative analysis of the Spanish native texts provided a linguistic profile for the verb. This profile was then used in a contextual study to assess the appropriateness of the 360 instances found in the translated texts. The results indicate thatobservaris only a natural translation equivalent for ‘observe’. For other verbs, an awareness both of the rhetorical, syntactic and collocational restrictions and of the range of alternative choices will allow translators to select appropriate lexical items and avoid excessive repetition ofobservar, thus creating a more varied target text.
Translation curriculum and pedagogy
Authors: Defeng Li
Published: July 2012

Following an earlier study on professional translators which appears in Target 2000, and another on translation students in Meta 2002, this article reports on an empirical study, based on both quantitative and qualitative data, on how administrators of translation/language services perceive translation training in Hong Kong. It will seek to answer questions such as the usual practice of and major considerations in recruitment of new translators; the major challenges the newly recruited face and methods and strategies they use to cope with them; the difficulties translators have in general as seen through the eyes of administrators, and the methods and strategies they use to cope with them; assistance translation agencies usually provide to help them deal with the challenges and difficulties; changes that need to be made to improve translator training. A comparison is made with my earlier projects on professional translators and translation students and pedagogical implications are also drawn in relation to some of the focal issues in translator training.
Literacy, rationality, and logic
Authors: Olson David R.
Published: July 2012

This paper examines the claim that writing turns the implicit properties of spoken language into visible objects suited to reflection and analysis. It examines this hypothesis through an analysis of relational terms including ‘and’, ‘or’, and ‘not’, their meanings and uses in ordinary conversational contexts, and the changes that occur when these terms are recruited for systematic logical thinking. Keywords:﻿﻿ literate rationality; literacy hypothesis; written register; relational term; logical thinking; logical discourse; metalinguistic judgement
Offline segmentation and online language processing units
Authors: Veldhuis Dorina , Kurvers Jeanne
Published: July 2012

Although metalinguistic (‘offline’) awareness of words as linguistic units has been related to literacy, it is still uncertain whether literacy also affects the units of language that people process unconsciously (‘online’). In this contribution, we first discuss the characteristics of offline and online tasks, opening up the perspective that such tasks vary in nature along a continuum ranging from more offline to more online. Subsequently, we present a study employing three relatively more offline and two more online tasks which we conducted among 83 preliterate and 121 literate children at Dutch primary schools. The results of the more offline tasks reveal a significant influence of literacy on segmentation along word-boundaries, while the results from the relatively more online tasks are less clear-cut with respect to the way in which literacy affects language processing. Keywords: literacy; language acquisition; metalinguistic awareness; online and offline task; word-segmentation; language processing; developmental psycholinguistics; Dutch
How subtle differences in orthography influence conceptual interpretation
Authors: Banga Arina , Hanssen Esther , Schreuder Robert , Neijt Anneke
Published: July 2012

The present study investigates linguistic relativity. The units of writing investigated are e and en, which are used to represent units of language in Dutch, Frisian, and Afrikaans. Dutch has homographic forms in the plural suffix -en and the linking element of noun-noun compounds en. Frisian does not have homography of this kind, while Afrikaans has a different homography. This raises the question whether second language learners of Dutch consistently interpret the linking en in Dutch noun-noun compounds as plural in the way that native speakers do. Plurality ratings for Dutch modifiers obtained from native Dutch speakers are compared with ratings from Frisian-Dutch bilinguals and Afrikaaners learning Dutch as L2. Significant differences relating to orthography are observed. We therefore argue that differing orthographic conventions in one’s native language (L1) can lead to different interpretations for the same everyday words written in Dutch (L2). Orthography thus provides an example of linguistic relativity. Keywords:﻿﻿ linguistic relativity; second language learning; morphology; compounding; linking element; plurality; homography; Dutch; Frisian; Afrikaans
Boundaries in written representations
Authors: Neef Martin
Published: July 2012

Formal theories of phonographic writing systems have to model, among other things, the regularities in the correspondences between written forms and phonological representations. In the ‘Recoding Model of Graphematics’ (Neef 2005a), correspondence rules for individual letters, supplemented with a set of constraints, serve this task. The aim of this paper is to argue that beyond these basic units, the morphological structure of written words plays a role in theories of phonographic writing systems as well. The relevant aspect of morphological structure is captured in a framework based on the boundary of the potential beginning of a word, which is motivated and evaluated on the basis of a detailed analysis of data from German. Keywords: graphematics; phonographic writing systems; letter; correspondence rule; graphematic domain; graphematic boundary; graphematic word; morphological structure
Orthographic representation and variation within the Japanese writing system
Authors: Joyce Terry , Hodošček Bor , Nishina Kikuko
Published: July 2012

Given its multi-scriptal nature, the Japanese writing system can potentially yield some important insights into the complex relationships that can exist between units of language and units of writing. This paper discusses some of the difficult issues surrounding the notions of orthographic representation and variation within the Japanese writing system, as seen from the perspective of creating word lists based on the Kokuritsu Kokugo Kenkyūjo’s ‘Balanced Corpus of Contemporary Written Japanese’ (BCCWJ) Project. More specifically, the paper (i) reflects on the treatment of lemmas within UniDic, the morphological analyzer dictionary developed for the project, (ii) notes some concerns for extracting word lists that stem from the project’s approach towards defining orthographic words which draws on its conceptualization of short and long unit words, and (iii) attempts to quantify the extent of orthographic variation within the Japanese writing system as represented by the BCCWJ. Keywords:﻿﻿ Japanese; Balanced Corpus of Contemporary Written Japanese (BCCWJ); kanji; hiragana; katakana; orthographic variation; UniDic
Genetic Analysis Reveals Dispersal of Florida Bass Haplotypes from Reservoirs to Rivers in Central Texas
Authors: Ray Jesse W. , Husemann Martin , King Ryan S. , Danley Patrick D.
Published: July 2012

We analyzed the genetic structure of putative largemouth bass Micropterus salmoides populations in nonstocked, wadeable streams of central Texas. Mitochondrial D‐loop sequences were generated for 69 fish sampled for this project. In addition, 27 largemouth bass and Florida bass M. floridanus specimens provided by the Texas Parks and Wildlife Department (TPWD) were sequenced. The TPWD samples represented stock lineages as well as wild fish from outside of the sampling region. Our analyses revealed the presence of both largemouth bass and Florida bass mitochondrial haplotypes at all sampling locations. Haplotypes of the nonnative Florida bass accounted for 26% of all haplotypes. The presence of Florida bass haplotypes at the sampling locations indicates that the influence of stocking reaches far beyond managed reservoirs. The admixture of nonnative genetic material can increase genetic diversity of native populations, but outbreeding depression, competition, and other negative impacts are of concern. Although the stocking of nonnative Florida bass in reservoirs may enhance fishing opportunities, it also has the ability to alter stream systems that are directly connected to stocked reservoirs.
Between ethnopolitics and liberal centrism: the Movement for Rights and Freedoms in the mainstream of Bulgarian party politics
Authors: Stefanova Boyka
Published: July 2012

This paper examines a less researched aspect of East European party politics: change within ethnic parties, which are conventionally regarded as stable or intransigent political actors. The main argument of the paper is that the decreasing relevance of a bipolar model of political competition has affected the relative positioning of ethnic parties. Their programmatic outlook, role in the party system, and mobilization strategies are being mainstreamed. Ethnic parties are no longer regarded as inevitable participants in power sharing and informal elite accommodation. They are increasingly treated by voters and the party system alike as national-level parties and national-level competitors. The paper applies the concept of mainstreaming to explain the long-term evolution of the Movement for Rights and Freedoms in Bulgarian party politics as a critical case study of ethnic party repositioning from proximity to government to parliamentary opposition. It builds an argument about the MRF's continued relevance to the party system, ensuring minority representation beyond ethnicity, as a liberal-centrist party representing distinct economic interests and political orientations within the Bulgarian electorate.
Evaluation of Osmotic Induction of Calcein Treatments for Marking Juvenile Walleyes
Authors: Logsdon Dale E. , Pittman Bruce J.
Published: July 2012

Osmotic induction of calcein was evaluated as a nonlethally detectable alternative to immersion in oxytetracycline for batch marking 42–58-d old walleyes Sander vitreus. A preliminary laboratory study and five larger-scale pond experiments were conducted to evaluate mark efficacy, mark retention, and tolerance to immersion in solutions of salt at 25 g/L or 50 g/L of water followed by immersion in a solution of calcein at 5 g/L of water. Walleyes became obviously stressed when immersed in the salt solutions, and mortalities immediately following the treatments ranged from 0% to 53%. All surviving walleyes possessed marks visible with a hand-held detector. However, the intensity of marks decreased exponentially on walleyes held in ponds, and only walleyes treated by initial immersion in the salt solution of 50 g/L possessed detectable marks when harvested 17–19 weeks posttreatment. The brightest marks occurred on structures most protected from sunlight. Marks on pelvic scales removed at time of capture also remained visible via epifluorescent microscopy for at least 2 weeks when stored in a freezer. These results suggest that osmotic induction of calcein would be a suitable method of producing nonlethally detectable marks for short-term stocking evaluations if techniques to reduce the stress induced by the marking process could be deployed.

Received December 12, 2011; accepted May 1, 2012
Spleen Index and Mannose-Binding Lectin Levels in Four Channel Catfish Families Exhibiting Different Susceptibilities to Flavobacterium columnare and Edwardsiella ictaluri
Authors: LaFrentz Benjamin R. , Shoemaker Craig A. , Booth Natha J. , Peterson Brian C. , Ourth Donald D.
Published: July 2012

Edwardsiella ictaluri and Flavobacterium columnare are two bacterial pathogens that affect channel catfish Ictalurus punctatus aquaculture. At the Catfish Genetics Research Unit (U.S. Department of Agriculture, Agricultural Research Service), some progress has been made in selectively breeding for resistance to E. ictaluri; however, the susceptibility of these families to F. columnare is not known. Our objectives were to obtain baseline information on the susceptibility of channel catfish families (maintained as part of the selective breeding program) to E. ictaluri and F. columnare and to determine whether the spleen index and plasma levels of mannose-binding lectin (MBL) are predictive indicators of susceptibility to these pathogens. Four channel catfish families were used: family A was randomly chosen from spawns of fish that were not selectively bred for resistance; families B, C, and D were obtained after selection for resistance to E. ictaluri. All four families were immersion challenged with both bacterial pathogens; the spleen index and plasma MBL levels of unchallenged fish from each family were determined. Mean cumulative percent mortality (CPM) after E. ictaluri challenge ranged from 4% to 33% among families. Families A and B were more susceptible to F. columnare (mean CPM of three independent challenges = 95% and 93%) than families C and D (45% and 48%), demonstrating that there is genetic variation in resistance to F. columnare. Spleen index values and MBL levels were not significantly different, indicating that these metrics are not predictive indicators of F. columnare or E. ictaluri susceptibility in the four tested families. Interestingly, the two families that exhibited the highest CPM after F. columnare challenges had the lowest CPM after E. ictaluri challenge. Further research on larger numbers of families is needed to determine whether there is any genetic correlation between resistance to E. ictaluri and resistance to F. columnare.

Received November 18, 2011; accepted February 23, 2012
A data-driven model of a modal gated ion channel: The inositol 1,4,5-trisphosphate receptor in insect Sf9 cells
Authors: Ullah Ghanim , Daniel Mak Don-On , Pearson John E.
Published: July 2012

The inositol 1,4,5-trisphosphate (IP3) receptor (IP3R) channel is crucial for the generation and modulation of intracellular Ca2+ signals in animal cells. To gain insight into the complicated ligand regulation of this ubiquitous channel, we constructed a simple quantitative continuous-time Markov-chain model from the data. Our model accounts for most experimentally observed gating behaviors of single native IP3R channels from insect Sf9 cells. Ligand (Ca2+ and IP3) dependencies of channel activity established six main ligand-bound channel complexes, where a complex consists of one or more states with the same ligand stoichiometry and open or closed conformation. Channel gating in three distinct modes added one complex and indicated that three complexes gate in multiple modes. This also restricted the connectivity between channel complexes. Finally, latencies of channel responses to abrupt ligand concentration changes defined a model with specific network topology between 9 closed and 3 open states. The model with 28 parameters can closely reproduce the equilibrium gating statistics for all three gating modes over a broad range of ligand concentrations. It also captures the major features of channel response latency distributions. The model can generate falsifiable predictions of IP3R channel gating behaviors and provide insights to both guide future experiment development and improve IP3R channel gating analysis. Maximum likelihood estimates of the model parameters and of the parameters in the De Young–Keizer model yield strong statistical evidence in favor of our model. Our method is simple and easily applicable to the dynamics of other ion channels and molecules.
The delayed rectifier potassium conductance in the sarcolemma and the transverse tubular system membranes of mammalian skeletal muscle fibers
Authors: DiFranco Marino , Quinonez Marbella , Vergara Julio L.
Published: July 2012

A two-microelectrode voltage clamp and optical measurements of membrane potential changes at the transverse tubular system (TTS) were used to characterize delayed rectifier K currents (IKV) in murine muscle fibers stained with the potentiometric dye di-8-ANEPPS. In intact fibers, IKV displays the canonical hallmarks of KV channels: voltage-dependent delayed activation and decay in time. The voltage dependence of the peak conductance (gKV) was only accounted for by double Boltzmann fits, suggesting at least two channel contributions to IKV. Osmotically treated fibers showed significant disconnection of the TTS and displayed smaller IKV, but with similar voltage dependence and time decays to intact fibers. This suggests that inactivation may be responsible for most of the decay in IKV records. A two-channel model that faithfully simulates IKV records in osmotically treated fibers comprises a low threshold and steeply voltage-dependent channel (channel A), which contributes ∼31% of gKV, and a more abundant high threshold channel (channel B), with shallower voltage dependence. Significant expression of the IKV1.4 and IKV3.4 channels was demonstrated by immunoblotting. Rectangular depolarizing pulses elicited step-like di-8-ANEPPS transients in intact fibers rendered electrically passive. In contrast, activation of IKV resulted in time- and voltage-dependent attenuations in optical transients that coincided in time with the peaks of IKV records. Normalized peak attenuations showed the same voltage dependence as peak IKV plots. A radial cable model including channels A and B and K diffusion in the TTS was used to simulate IKV and average TTS voltage changes. Model predictions and experimental data were compared to determine what fraction of gKV in the TTS accounted simultaneously for the electrical and optical data. Best predictions suggest that KV channels are approximately equally distributed in the sarcolemma and TTS membranes; under these conditions, >70% of IKV arises from the TTS.
Regulation of voltage-gated potassium channels by PI(4,5)P2
Authors: Kruse Martin , Hammond Gerald R.V. , Hille Bertil
Published: July 2012

Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) regulates activities of numerous ion channels including inwardly rectifying potassium (Kir) channels, KCNQ, TRP, and voltage-gated calcium channels. Several studies suggest that voltage-gated potassium (KV) channels might be regulated by PI(4,5)P2. Wide expression of KV channels in different cells suggests that such regulation could have broad physiological consequences. To study regulation of KV channels by PI(4,5)P2, we have coexpressed several of them in tsA-201 cells with a G protein–coupled receptor (M1R), a voltage-sensitive lipid 5-phosphatase (Dr-VSP), or an engineered fusion protein carrying both lipid 4-phosphatase and 5-phosphatase activity (pseudojanin). These tools deplete PI(4,5)P2 with application of muscarinic agonists, depolarization, or rapamycin, respectively. PI(4,5)P2 at the plasma membrane was monitored by Förster resonance energy transfer (FRET) from PH probes of PLCδ1 simultaneously with whole-cell recordings. Activation of Dr-VSP or recruitment of pseudojanin inhibited KV7.1, KV7.2/7.3, and Kir2.1 channel current by 90–95%. Activation of M1R inhibited KV7.2/7.3 current similarly. With these tools, we tested for potential PI(4,5)P2 regulation of activity of KV1.1/KVβ1.1, KV1.3, KV1.4, and KV1.5/KVβ1.3, KV2.1, KV3.4, KV4.2, KV4.3 (with different KChIPs and DPP6-s), and hERG/KCNE2. Interestingly, we found a substantial removal of inactivation for KV1.1/KVβ1.1 and KV3.4, resulting in up-regulation of current density upon activation of M1R but no changes in activity upon activating only VSP or pseudojanin. The other channels tested except possibly hERG showed no alteration in activity in any of the assays we used. In conclusion, a depletion of PI(4,5)P2 at the plasma membrane by enzymes does not seem to influence activity of most tested KV channels, whereas it does strongly inhibit members of the KV7 and Kir families.
Domain structure and piezoelectric response in lanthanide rare earth-substituted multiferroic BiFeO3 thin films
Authors: Yan F , Lai M O , Lu Li
Published: July 2012

The microstructure, domain structure and piezoelectric response in lanthanide rare-earth ion (Ln) substituted BiFeO3 (BFO) thin films are investigated systematically. Although most of the peaks in the x-ray patterns of the rare-earth-substituted BFO films are consistent with the rhombohedral crystal structure, the patterns of the Ce-, Eu- and Yb-doped samples indicate that the films contain a small amount of tetragonal impurity phase. The piezoelectric properties are enhanced due to the increased relative Bi–O displacement and the rotation of FeO6 octahedra. Meanwhile, the domain structures of BFO films become more homogeneous by inserting Ln ions. Furthermore, the piezoresponse properties are improved by introducing Ln ions, which is attributed to the variation of ionic strength of bands between Ln ions and O ions caused by chemical modification and a lower symmetry structure
An ab initio study of MgO epitaxial layers on a Co2MnSi (0 0 1) surface: influence of the interface structure on tunnelling conductance
Authors: Yu H L , Jiang X F , Zheng Y , Yang G W
Published: July 2012

The formation of MgO epitaxial layers on a Co2MnSi (0 0 1) surface was studied using the ab initio electronic structure calculations based on the density functional theory. The free energy calculations showed that the O-rich, O-top and Mg-rich configurations in the CoCo termination case, and the O-rich and O-top configurations in the MnSi termination case were thermodynamically stable. The magnetic and electronic properties of these stable configurations were investigated in detail, and the results indicated that only the Mg-rich configuration with CoCo termination exhibited near half-metallic properties at the interface. The influence of the interfacial structure on the tunnelling conductance of the Co2MnSi/MgO/Co2MnSi magnetic tunnel junctions (MTJs) was also discussed using the nonequilibrium Green's function method. The attained conductance showed that a large difference of up to 104 was observed in the magnitude of parallel conductance, which means that the interface structure plays a crucial role in the electronic transport of the MTJ. These findings are useful in designing MTJs with high performance.
White long-lasting phosphorescence generation in a CaAl2Si2O8 : Eu2+, Mn2+, Dy3+ system through persistent energy transfer
Authors: Zhang Jinsu , Chen Baojiu , Sun Jiashi , Li Xiangping , Cheng Lihong , Zhong Haiyang
Published: July 2012

Based on the persistent energy transfer principle, Mn2+ was introduced into a CaAl2Si2O8 : Eu2+/Dy3+ phosphor to achieve white long-lasting emissions. Eu2+, Mn2+ and Dy3+ tri-doped CaAl2Si2O8 phosphors with various Mn2+ concentrations were prepared via a solid-state reaction, and the crystal structure of the phosphors was identified by the x-ray diffraction technique. The luminescent properties of the Eu2+, Mn2+ and Dy3+ tri-doped CaAl2Si2O8 phosphors were studied. The energy transfer behaviour from Eu2+ to Mn2+ was analysed within the framework of Dexter theory. The physical mechanism of energy transfer was assigned to the electric dipole–quadrupole interaction. It was also demonstrated that the colour coordinates of the phosphors can be tuned from the blue region to the white region in the colour space. Furthermore, the afterglow decay and thermoluminescence curves were measured, indicating excellent phosphorescence properties of the current phosphors.