Non-verbal inhibitory control of proactive interference in a probe-recognition task

Thesis (B.Sc)--University of Hong Kong, 2010.Includes bibliographical references (p. 28-30)."A dissertation submitted in partial fulfillment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, June 30, 2010."The present study investigated nonverbal inhibitory control of proactive interference in normal individuals using a probe-recognition task. Visual stimuli consisted of 130 abstract figures selected or modified from the Aggie Figure Learning Test (Majdan, Sziklas, & Jones-Gotman, 1996). The performance of 34 undergraduate participants showed a significant visual similarity interference effect, indicated by prolonged response times and reduced accuracy rates, only when the target probe was related to an item in the negative same list condition but not in the negative previous list condition. This implied that the effect of non-verbal proactive interference affected items that were relevant, in the same trial, and did not extend to items that were no longer relevant, in the following trial. The present findings suggest evidence for an inhibitory control process being carried out to prevent cross-trial visual similarity interference. Possible modifications to the negative same list condition for improving test validity are discussed.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science

Analisis Pengaruh Pengembangan Pariwisata terhadap Kepuasan Wisatawan di Kawasan Wisata Bukit Indah Simarjarunjung Desa Pariksabungan Kabupaten Simalungun

Penelitian ini bertujuan untuk mengetahui pengaruh pengembangan pariwisata dalam hal ini  atraksi, aksesibilitas, amenitas dan layanan ancillary terhadap kepuasan wisatawan di Kawasan Wisata Bukit Indah Simarjarunjung Kabupaten Simalungun. Metode yang digunakan dengan metode survey dengan menggunakan kuesioner model Likert yang disebar dengan menggunakan Google Form. Metode pemilihan sampel dengan menggunakan simple random sampling dengan jumlah responden sebanyak 116 orang. Penelitian ini menggunakan analisis deskriptif dengan pendekatan kuantitatif dengan regresi linear berganda. Setiap variabel bebas (X) kemudian dilakukan uji t dan uji f terhadap variabel terikat (Y).Hasil penelitian menunjukkan bahwa Ataksi, Aksesibilitas, Amenitas dan Layanan Asilari berpengaruh positif dan signifikan baik secara parsial maupun secara simultan terhadap kepuasan wisatawan di Kawasan Wisata Bukit Indah Simarjarunjung Kabupaten Simalungun. Dari hasil uji dominan diperoleh bahwa atraksi wisata merupakan variabel yang paling berpengaruh terhadap kepuasan wisatawan. Amenitas merupakan variabel yang paling harus mendapat perhatian untuk diupayakan pengembangannya

An investigation on oxidation/carburisation of 9Cr-1Mo steel heat exchanger tube in an AGR environment

9Cr-1Mo steels have been used extensively in the power generation industry. In this study, a wide range of experimental samples exposed at different times and temperatures in a CO2 environment were analysed to look at the development of the metal and oxides over time. The main objective of this work was to obtain a better understanding of the carburisation and oxidation behaviour of 9Cr 1Mo steels as a function of temperature/time, with special attention paid to the transition from protective to breakaway oxidation. In addition, experiments were also carried out to investigate any links between oxidation transition and carburisation behaviour of these materials

A new designed incremental high pressure torsion process for producing long nanostructured rod samples

High pressure torsion (HPT) is one of the most important and effective severe plastic deformation (SPD) processes for producing nanostructured (NS) and ultrafine grained (UFG) metals. Whereas HPT presents excellent mechanical properties, its applications are limited to small disk-shaped samples. In this study a new design of incremental HPT (IHPT) process entitled SIHPT is developed which is much convenient for the production of large NS and UFG metallic rods. In this new design, some steppers along the length of the rod-shaped sample are used while applying an axial load from two ends of it. Step twisting of stepper parts with simultaneous axial loads extend the deformed region to the whole length of the sample. The five turn IHPT process was applied to a 50 mm length and 10 mm diameter pure copper sample and microstructure, and mechanical properties were evaluated. The microstructural study of SIHPT processed samples using TEM and EBSD micrographs clearly reflected the NS sample having an average grain size of less than 100 nm. Also, microhardness measurements showed that the sample has fairly good homogeneity through both axial and radial directions. Besides, tensile test measurements indicate that there is about four times improvement in yield strength of nanostructured sample compared to unprocessed metal which is accompanied with satisfactory ductility as a result of high hydrostatic compressive stresses

CRISPR-Cas9 ribonucleoprotein-mediated co-editing and counterselection in the rice blast fungus

The rice blast fungus Magnaporthe oryzae is the most serious pathogen of cultivated rice and a significant threat to global food security. To accelerate targeted mutation and specific genome editing in this species, we have developed a rapid plasmid-free CRISPR-Cas9-based genome editing method. We show that stable expression of Cas9 is highly toxic to M. oryzae. However efficient gene editing can be achieved by transient introduction of purified Cas9 pre-complexed to RNA guides to form ribonucleoproteins (RNPs). When used in combination with oligonucleotide or PCR-generated donor DNAs, generation of strains with specific base pair edits, in-locus gene replacements, or multiple gene edits, is very rapid and straightforward. We demonstrate a co-editing strategy for the creation of single nucleotide changes at specific loci. Additionally, we report a novel counterselection strategy which allows creation of precisely edited fungal strains that contain no foreign DNA and are completely isogenic to the wild type. Together, these developments represent a scalable improvement in the precision and speed of genetic manipulation in M. oryzae and are likely to be broadly applicable to other fungal species

The Role of Star Formation and an AGN in Dust Heating of z = 0.3–2.8 Galaxies. I. Evolution with Redshift and Luminosity

We characterize infrared spectral energy distributions of 343 (ultra)luminous infrared galaxies from z = 0.3–2.8. We diagnose the presence of an active galactic nucleus (AGN) by decomposing individual Spitzer mid-IR spectroscopy into emission from star formation and an AGN-powered continuum; we classify sources as star-forming galaxies (SFGs), AGNs, or composites. Composites comprise 30% of our sample and are prevalent at faint and bright S_(24), making them an important source of IR AGN emission. We combine spectroscopy with multiwavelength photometry, including Herschel imaging, to create three libraries of publicly available templates (2–1000 μm). We fit the far-IR emission using a two-temperature modified blackbody to measure cold and warm dust temperatures (T_c and T_w). We find that T_c does not depend on mid-IR classification, while T_w shows a notable increase as the AGN grows more luminous. We measure a quadratic relationship between mid-IR AGN emission and total AGN contribution to LIR. AGNs, composites, and SFGs separate in S_8/S_(3.6) and S_(250)/S_(24), providing a useful diagnostic for estimating relative amounts of these sources. We estimate that >40% of IR-selected samples host an AGN, even at faint selection thresholds (S_(24) > 100 μJy). Our decomposition technique and color diagnostics are relevant given upcoming observations with the James Webb Space Telescope

A controlled study of cold dust content in galaxies from z=0−2z=0-2

At $z=1-3$, the formation of new stars is dominated by dusty galaxies whose far-IR emission indicates they contain colder dust than local galaxies of a similar luminosity. We explore the reasons for the evolving IR emission of similar galaxies over cosmic time using: 1) Local galaxies from GOALS $(L_{\rm IR}=10^{11}-10^{12}\,L_\odot)$; 2) Galaxies at $z\sim0.1-0.5$ from the 5MUSES ($L_{\rm IR}=10^{10}-10^{12}\,L_\odot$); 3) IR luminous galaxies spanning $z=0.5-3$ from GOODS and Spitzer xFLS ($L_{\rm IR}>10^{11}\,L_\odot$). All samples have Spitzer mid-IR spectra, and Herschel and ground-based submillimeter imaging covering the full IR spectral energy distribution, allowing us to robustly measure $L_{\rm IR}^{\rm\scriptscriptstyle SF}$, $T_{\rm dust}$, and $M_{\rm dust}$ for every galaxy. Despite similar infrared luminosities, $z>0.5$ dusty star forming galaxies have a factor of 5 higher dust masses and 5K colder temperatures. The increase in dust mass is linked with an increase in the gas fractions with redshift, and we do not observe a similar increase in stellar mass or star formation efficiency. $L_{160}^{\rm\scriptscriptstyle SF}/L_{70}^{\rm\scriptscriptstyle SF}$, a proxy for $T_{\rm dust}$, is strongly correlated with $L_{\rm IR}^{\rm\scriptscriptstyle SF}/M_{\rm dust}$ independently of redshift. We measure merger classification and galaxy size for a subsample, and there is no obvious correlation between these parameters and $L_{\rm IR}^{\rm \scriptscriptstyle SF}/M_{\rm dust}$ or $L_{160}^{\rm\scriptscriptstyle SF}/L_{70}^{\rm\scriptscriptstyle SF}$. In dusty star forming galaxies, the change in $L_{\rm IR}^{\rm\scriptscriptstyle SF}/M_{\rm dust}$ can fully account for the observed colder dust temperatures, suggesting that any change in the spatial extent of the interstellar medium is a second order effect.Comment: Accepted for publication in ApJ. 21 pages, 11 figure

A bioresorbable peripheral nerve stimulator for electronic pain block

Local electrical stimulation of peripheral nerves can block the propagation of action potentials, as an attractive alternative to pharmacological agents for the treatment of acute pain. Traditional hardware for such purposes, however, involves interfaces that can damage nerve tissue and, when used for temporary pain relief, that impose costs and risks due to requirements for surgical extraction after a period of need. Here, we introduce a bioresorbable nerve stimulator that enables electrical nerve block and associated pain mitigation without these drawbacks. This platform combines a collection of bioresorbable materials in architectures that support stable blocking with minimal adverse mechanical, electrical, or biochemical effects. Optimized designs ensure that the device disappears harmlessly in the body after a desired period of use. Studies in live animal models illustrate capabilities for complete nerve block and other key features of the technology. In certain clinically relevant scenarios, such approaches may reduce or eliminate the need for use of highly addictive drugs such as opioids

The mid-IR Luminosity Function at z<0.3 from 5MUSES: Understanding the Star-formation/AGN Balance from a Spectroscopic View

We present rest-frame 15 and 24 um luminosity functions and the corresponding star-forming luminosity functions at z<0.3 derived from the 5MUSES sample. Spectroscopic redshifts have been obtained for ~98% of the objects and the median redshift is ~0.12. The 5-35 um IRS spectra allow us to estimate accurately the luminosities and build the luminosity functions. Using a combination of starburst and quasar templates, we quantify the star-formation and AGN contributions in the mid-IR SED. We then compute the star-formation luminosity functions at 15 um and 24 um, and compare with the total 15 um and 24 um luminosity functions. When we remove the contribution of AGN, the bright end of the luminosity function exhibits a strong decline, consistent with the exponential cutoff of a Schechter function. Integrating the differential luminosity function, we find that the fractional contribution by star formation to the energy density is 58% at 15 um and 78% at 24 um, while it goes up to ~86% when we extrapolate our mid-IR results to the total IR luminosity density. We confirm that the active galactic nuclei play more important roles energetically at high luminosities. Finally, we compare our results with work at z~0.7 and confirm that evolution on both luminosity and density is required to explain the difference in the LFs at different redshifts.Comment: 31 pages, 12 figures, accepted for Ap