397 research outputs found
Epenthetic vowels in Japanese: A perceptual illusion?
In four cross-linguistic experiments comparing French and Japanese hearers, we found that the phonotactic properties of Japanese (very reduced set of syllable types) induce Japanese listeners to perceive ``illusory'' vowels inside consonant clusters in VCCV stimuli. In Experiments 1 and 2, we used a continuum of stimuli ranging from no vowel (e.g. ebzo) to a full vowel between the consonants (e.g. ebuzo). Japanese, but not French participants, reported the presence of a vowel [u] between consonants, even in stimuli with no vowel. A speeded ABX discrimination paradigm was used in Experiments 3 and 4, and revealed that Japanese participants had trouble discriminating between VCCV and VCuCV stimuli. French participants, in contrast had problems discriminating items that differ in vowel length (ebuzo vs. ebuuzo), a distinctive contrast in Japanese but not in French. We conclude that models of speech perception have to be revised to account for phonotactically-based assimilations
Epenthetic vowels in Japanese: A perceptual illusion?
International audienceWe report a set of experiments demonstrating that the number of phonemes perceived in a stimulus depends on the native language of the listener. Comparing French and Japanese subjects we found that the phonotactic properties of the native language can induce subjects to insert "illusory" segments. In Experiment 1, we varied the duration of an inter-consonantal vowel [u] in stimuli such as ebuzo and found that unlike the French, Japanese listeners report that the vowel [u] is present even in stimuli in which the vowel is absent. In Experiment 2 and 3 using an ABX task, we show that Japanese subjects have trouble discriminating stimuli that contain an [u] vowel from stimuli in which the vowel is absent, e.g., (ebuzo vs. ebzo). However, they can easily discriminate items that contain one versus two [u] vowels, e.g., ebuzo vs. ebuuzo, a distinctive contrast in Japanese. Results for French subjects are reversed
Perihilar or (Hilar) Cholangiocarcinoma: Interventional to Surgical Management
Peri-hilar cholangiocarcinoma (PHC) or hilar cholangiocarcinoma (HCCA) characterizes a critical effort to assess significantly sick patients. The existing scenery and proof to the diagnosis and treatments for hilar cholangiocarcinoma are improving day by day. Patients with HCCA encounter numerous obstacles in acquiring efficient therapies. The condition is uncommon, and the majority patients don’t have any distinct risk factors, doing selection process inadequate. The initial signs and symptoms in many cases are non-specific, and in many patients the tumors are not resectable because of involvement of the perihilar structures. MRI with MRCP offers further information about the extent of biliary involvement. Furthermore, endoscopic stenting and percutaneous drain could be useful for intricate hilar strictures. Surgical resections with negative margins are related to good likelihood of survival for patients representing with HCCA. Regardless of the accessibility of curative treatment strategies such as operative resection and liver transplantation, most sufferers with HCCA shows with repeated, metastases or locally advanced disease with a poor prognosis. Within this chapter, we have tried to elaborate the modalities of treatment from intervention to surgical approach for HCCA
Strong and Specific Recognition of CAG/CTG Repeat DNA (5'-dWGCWGCW-3') by a Cyclic Pyrrole-Imidazole Polyamide
Abnormally expanded CAG/CTG repeat DNA sequences lead to a variety of neurological diseases, such as Huntington's disease. Here, we synthesized a cyclic pyrrole-imidazole polyamide (cPIP), which can bind to the minor groove of the CAG/CTG DNA sequence. The double-stranded DNA melting temperature (Tm ) and surface plasmon resonance assays revealed the high binding affinity of the cPIP. In addition, next-generation sequencing showed that the cPIP had high specificity for its target DNA sequence
Increased vesicle fusion competence underlies long-term potentiation at hippocampal mossy fiber synapses
Presynaptic long-term potentiation (LTP) is thought to play an important role in learning and memory. However, the underlying mechanism remains elusive because of the difficulty of direct recording during LTP. Hippocampal mossy fiber synapses exhibit pronounced LTP of transmitter release after tetanic stimulation and have been used as a model of presynaptic LTP. Here, we induced LTP by optogenetic tools and applied direct presynaptic patch-clamp recordings. The action potential waveform and evoked presynaptic Ca2+ currents remained unchanged after LTP induction. Membrane capacitance measurements suggested higher release probability of synaptic vesicles without changing the number of release-ready vesicles after LTP induction. Synaptic vesicle replenishment was also enhanced. Furthermore, stimulated emission depletion microscopy suggested an increase in the numbers of Munc13-1 and RIM1 molecules within active zones. We propose that dynamic changes in the active zone components may be relevant for the increased fusion competence and synaptic vesicle replenishment during LTP
Catabolic regulation analysis of Escherichia coli and its crp, mlc, mgsA, pgi and ptsG mutants
<p>Abstract</p> <p>Background</p> <p>Most bacteria can use various compounds as carbon sources. These carbon sources can be either co-metabolized or sequentially metabolized, where the latter phenomenon typically occurs as catabolite repression. From the practical application point of view of utilizing lignocellulose for the production of biofuels etc., it is strongly desirable to ferment all sugars obtained by hydrolysis from lignocellulosic materials, where simultaneous consumption of sugars would benefit the formation of bioproducts. However, most organisms consume glucose prior to consumption of other carbon sources, and exhibit diauxic growth. It has been shown by fermentation experiments that simultaneous consumption of sugars can be attained by <it>ptsG, mgsA </it>mutants etc., but its mechanism has not been well understood. It is strongly desirable to understand the mechanism of metabolic regulation for catabolite regulation to improve the performance of fermentation.</p> <p>Results</p> <p>In order to make clear the catabolic regulation mechanism, several continuous cultures were conducted at different dilution rates of 0.2, 0.4, 0.6 and 0.7 h<sup>-1 </sup>using wild type <it>Escherichia coli</it>. The result indicates that the transcript levels of global regulators such as <it>crp, cra, mlc </it>and <it>rpoS </it>decreased, while those of <it>fadR, iclR, soxR/S </it>increased as the dilution rate increased. These affected the metabolic pathway genes, which in turn affected fermentation result where the specific glucose uptake rate, the specific acetate formation rate, and the specific CO<sub>2 </sub>evolution rate (CER) were increased as the dilution rate was increased. This was confirmed by the <sup>13</sup>C-flux analysis. In order to make clear the catabolite regulation, the effect of <it>crp </it>gene knockout (Δ<it>crp</it>) and crp enhancement (<it>crp<sup>+</sup></it>) as well as <it>mlc, mgsA, pgi </it>and <it>ptsG </it>gene knockout on the metabolism was then investigated by the continuous culture at the dilution rate of 0.2 h<sup>-1 </sup>and by some batch cultures. In the case of Δ<it>crp </it>(and also Δ<it>mlc</it>) mutant, TCA cycle and glyoxylate were repressed, which caused acetate accumulation. In the case of <it>crp<sup>+ </sup></it>mutant, glycolysis, TCA cycle, and gluconeogenesis were activated, and simultaneous consumption of multiple carbon sources can be attained, but the glucose consumption rate became less due to repression of <it>ptsG </it>and <it>ptsH </it>by the activation of Mlc. Simultaneous consumption of multiple carbon sources could be attained by <it>mgsA, pgi</it>, and <it>ptsG </it>mutants due to increase in <it>crp </it>as well as <it>cyaA</it>, while glucose consumption rate became lower.</p> <p>Conclusions</p> <p>The transcriptional catabolite regulation mechanism was made clear for the wild type <it>E. coli</it>, and its <it>crp, mlc, ptsG, pgi, and mgsA </it>gene knockout mutants. The results indicate that catabolite repression can be relaxed and <it>crp </it>as well as <it>cyaA </it>can be increased by <it>crp<sup>+</sup>, mgsA, pgi</it>, and <it>ptsG </it>mutants, and thus simultaneous consumption of multiple carbon sources including glucose can be made, whereas the glucose uptake rate became lower as compared to wild type due to inactivation of <it>ptsG </it>in all the mutants considered.</p
Cystic Artery Variations and Associated Vascular Complications in Laparoscopic Cholecystectomy
Substantial knowledge of the arterial supply and its anatomical variations of the gall bladder and liver are important in all the hepatobiliary surgical procedures. The arterial supply of gallbladder called cystic artery (CA) is a vital structure required to get ligated or clipped in the path of laparoscopic cholecystectomy. The possible concerns like intra-operative bleeding or adjoining accidental injuries will almost always be focused on the research consisting of dissection and clipping with cystic artery. Pseudoaneurysm of the cystic artery has additionally been belonging to the presence of acute cholecystitis or pancreatitis. An original supply of CA is usually assessed depending on the existence of hepatic artery variants. Laparoscopic cholecystectomy is really a recent and arduous noninvasive procedure and might even result in substantial unintended effects possibly iatrogenic or in the form of post-procedural complications. The perfect knowledge of anatomy in addition to feasible variation of cystic artery is mandatory. An efficient operative strategy and consciousness are probably the key components with all the results and marginal likelihood of complications, which often can be ultimately attainable. Within this chapter, we have attempted to explore some variations of cystic artery, complications and management
Ischemia-Reperfusion Injury of the Cochlea: Pharmacological Strategies for Cochlear Protection and Implications of Glutamate and Reactive Oxygen Species
A large amount of energy produced by active aerobic metabolism is necessary for the cochlea to maintain its function. This makes the cochlea vulnerable to blockade of cochlear blood flow and interruption of the oxygen supply. Although certain forms of human idiopathic sudden sensorineural hearing loss reportedly arise from ischemic injury, the pathological mechanism of cochlear ischemia-reperfusion injury has not been fully elucidated. Recent animal studies have shed light on the mechanisms of cochlear ischemia-reperfusion injury. It will help in the understanding of the pathology of cochlear ischemia-reperfusion injury to classify this injury into ischemic injury and reperfusion injury. Excitotoxicity, mainly observed during the ischemic period, aggravates the injury of primary auditory neurons. On the other hand, oxidative damage induced by hydroxyl radicals and nitric oxide enhances cochlear reperfusion injury. This article briefly summarizes the generation mechanisms of cochlear ischemia-reperfusion injury and potential therapeutic targets that could be developed for the effective management of this injury type
Two floating camphor particles interacting through lateral capillary force
We consider a mathematical model for a two-particle system driven by the
spatial gradient of a concentration field of chemicals with conservative
attractive interactions in one dimension. This setup corresponds to an
experimental system with floating camphor particles at a water surface.
Repulsive interaction is introduced, as well as self-propelling force, through
the concentration field of camphor molecules at the water surface. Here we
newly adopt the attractive lateral capillary force due to the deformation of
the water surface. The particles experience competing dissipative repulsion and
conservative attraction. We numerically investigated the mathematical model,
and found six different modes of motion. The theoretical approach revealed that
some of such mode transitions can be understood in terms of bifurcation.Comment: 9 pages, 6 figure
Characteristic expression of twelve rice PR1 family genes in response to pathogen infection, wounding, and defense-related signal compounds (121/180)
Pathogenesis-related (PR) proteins have been used as markers of plant defense responses, and are classified into 17 families. However, precise information on the majority members in specific PR families is still limited. We were interested in the individual characteristics of rice PR1 family genes, and selected 12 putatively active genes using rice genome databases for expressed genes. All were upregulated upon compatible and/or incompatible rice-blast fungus interactions; three were upregulated in the early infection period and four in the late infection period. Upon compatible rice–bacterial blight interaction, four genes were upregulated, six were not affected, and one was downregulated. These results are in striking contrast to those among 22 ArabidopsisPR1 genes where only one gene was pathogen-inducible. The responses of individual genes to salicylic acid, jasmonic acid, and ethylene induced defense signaling pathways in rice are likely to be different from those in dicot plants. Transcript levels in healthy leaves, roots, and flowers varied according to each gene. Analysis of the partially overlapping expression patterns of rice PR1 genes in healthy tissues and in response to pathogens and other stresses would be useful to understand their possible functions and for use as characteristic markers for defense-related studies in rice
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