Sound duration selectivity in bat midbrain inferior colliculus

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file (viewed on August 9, 2007)Vita.Thesis (Ph. D.) University of Missouri-Columbia 2006.Sound duration is an important acoustic parameter that contributes to the distinct spectral and temporal attributes of individual biological sounds and is therefore important for sound recognition in human speech, animal communication and bat echolocation. The main objective of this thesis is to examine the duration selectivity of neurons in the central nucleus of the midbrain inferior colliculus (IC) using bats as the mammalian model system under stimulation conditions of single pulses, temporally patterned pulse trains and pulse-echo (P-E) pairs. This thesis also studies the role of GABAergic inhibition in shaping the duration selectivity of IC neurons using iontophoretic application of GABA or bicuculline, which is an antagonist for GABAA receptors. The data obtained from these studies show the following. (1) Neurons at upper IC have sharper duration selectivity than neurons in the deeper IC. (2) GABAergic inhibition contributes to sharpening of duration selectivity of IC neurons to sound pulses in rapid sequences, pulse repetition rate (PRR) of pulse trains, and shortening of pulse duration and P-E gap. (3) The effect of bicuculline application on duration selectivity is more pronounced at high than at low PRR while the opposite is true during GABA application.Includes bibliographical reference

Fidelity-Enriched Contrastive Search: Reconciling the Faithfulness-Diversity Trade-Off in Text Generation

In this paper, we address the hallucination problem commonly found in natural language generation tasks. Language models often generate fluent and convincing content but can lack consistency with the provided source, resulting in potential inaccuracies. We propose a new decoding method called Fidelity-Enriched Contrastive Search (FECS), which augments the contrastive search framework with context-aware regularization terms. FECS promotes tokens that are semantically similar to the provided source while penalizing repetitiveness in the generated text. We demonstrate its effectiveness across two tasks prone to hallucination: abstractive summarization and dialogue generation. Results show that FECS consistently enhances faithfulness across various language model sizes while maintaining output diversity comparable to well-performing decoding algorithms.Comment: Accepted as a short paper at EMNLP 202

EBV-positive Hodgkin lymphoma is associated with suppression of p21cip1/waf1 and a worse prognosis

<p>Abstract</p> <p>Background</p> <p>About 30-50% of Hodgkin lymphomas (HLs) harbor the Epstein-Barr virus (EBV), but the impact of EBV infection on clinical outcomes has been unclear. EBV-encoded small RNAs (<it>EBER</it>s) are presented in all EBV-infected cells, but their functions are still less understood.</p> <p>Results</p> <p><it>EBER1 </it>was transfected into two HL cell lines, KMH2 and L428, and microarrays were used to screen for <it>EBER1</it>-induced changes. We found that <it>EBER1 </it>suppressed <it>p21</it>^cip1/waf1transcription in HL cell lines. In addition, positive regulators of <it>p21</it>^cip1/waf1transcription, such as p53, EGR1, and STAT1, were decreased. Suppression of <it>p21</it>^cip1/waf1in the <it>EBER1</it>⁺HL cell lines was associated with increased resistance to histone deacetylase inhibitors or proteasome inhibitors, drugs known to cause apoptosis by increasing p21^cip1/waf1levels. On biopsy specimens, EBV⁺HLs had weaker expression of both p21^cip1/waf1and active caspase 3. Clinically, suppression of p21^cip1/waf1in EBV⁺HLs was associated with a worse 2-year disease-free survival rate (45% for EBV⁺HLs <it>vs</it>. 77% for EBV^-HLs, <it>p </it>= 0.002).</p> <p>Conclusion</p> <p>Although the underlying mechanisms are still relatively unclear, <it>EBER1 </it>inhibits <it>p21</it>^cip1/waf1transcription and prevents apoptosis through down-regulation of p53, EGR1, and STAT1. The anti-apoptotic activity of <it>EBER1 </it>may be important in the rescue of Reed-Sternberg cells from drug-induced apoptosis and in the clinical behaviors of EBV⁺HLs.</p

Preparation of N- TiO

This study applied the microwave/sol-gel method to prepare nitrogen-doped TiO2 (N-TiO2). The N-TiO2 was immobilized in glass balls to form N-TiO2/glass beads and applied to degrade Bisphenol A (BPA) under visible-light and sunlight irradiation. The characteristics of the prepared photocatalysts were analyzed by X-ray diffraction (XRD), UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Experimental results demonstrate that the percentage of anatase increased as the amount of N in N-TiO2 increased. Compared with the undoped TiO2 (420 nm), spectra show that the absorption edge shifted to a longer wavelength (445 nm) after N doping. The XPS characterization confirms the substitution of crystal lattice O to N species in N-TiO2, forming Ti–O–N and N–Ti–O. With an increased N/Ti ratio, photodegradation efficiency increased and then decreased; moreover, the optimal amount for N doping was determined as an N/Ti mole ratio of 0.08 (0.1 NT). The efficiency of 0.1 NT in doing BPA photodegradation was greater than that of Degussa P25. After reaction for 61 min, the mineralization percentage of 0.1 NT under visible-light irradiation reached 41%. Photocatalyst efficiency decreased as the number of repeats increased in the visible-light/N-TiO2 system; however, these systems were stable during reaction