Spatial Sequestration and Oligomer Remodeling During \u3cem\u3ede novo\u3c/em\u3e [\u3cem\u3ePSI\u3c/em\u3e\u3csup\u3e+\u3c/sup\u3e] Formation

Prions are misfolded, aggregated, infectious proteins found in a range of organisms from mammals to bacteria. In mammals, prion formation is difficult to study because misfolding and aggregation take place prior to symptom presentation. The study of the yeast prion [PSI+], which is the misfolded infectious form of Sup35p, provides a tractable system to monitor prion formation in real time. Recently, we showed that the de novo formation of prion aggregates begins with the appearance of highly mobile cytoplasmic foci, called early foci, which assemble into larger ring or dot structures. We also observed SDS-resistant oligomers during formation, and lysates containing newly formed oligomers can convert [psi−] cells to the [PSI+] state, suggesting that these oligomers have infectious potential. Here, we further characterize two aspects of prion formation: spatial sequestration of early foci and oligomerization of endogenous Sup35p. Our data provides important insights into the process of prion formation and explores the minimal oligomer requirement for infectivity

Writing Assignments with a Metacognitive Component Enhance Learning in a Large Introductory Biology Course

Writing assignments, including note taking and written recall, should enhance retention of knowledge, whereas analytical writing tasks with metacognitive aspects should enhance higher-order thinking. In this study, we assessed how certain writing-intensive “interventions,” such as written exam corrections and peer-reviewed writing assignments using Calibrated Peer Review and including a metacognitive component, improve student learning. We designed and tested the possible benefits of these approaches using control and experimental variables across and between our three-section introductory biology course. Based on assessment, students who corrected exam questions showed significant improvement on postexam assessment compared with their nonparticipating peers. Differences were also observed between students participating in written and discussion-based exercises. Students with low ACT scores benefited equally from written and discussion-based exam corrections, whereas students with midrange to high ACT scores benefited more from written than discussion-based exam corrections. Students scored higher on topics learned via peer-reviewed writing assignments relative to learning in an active classroom discussion or traditional lecture. However, students with low ACT scores (17–23) did not show the same benefit from peer-reviewed written essays as the other students. These changes offer significant student learning benefits with minimal additional effort by the instructors

Mirroring the reality in interrogation rooms: A proposal to record interrogations in Singapore

Wrongful convictions are grave miscarriages of justice as the wrongfully convicted individuals endure catastrophic sufferings. Such convictions are only identified as ‘wrongful’ upon exonerations. The most basic wrongful conviction cases arise when individuals are adjudged guilty for crimes they did not commit (often known as ‘wrong man’ cases) or when convictions are obtained even though there was no commission of crimes (often known as ‘no crime’ cases). Though of noteworthy concern, cases of wrongful convictions plagued by ‘no crime’ errors are beyond the scope of this paper. Rather, this paper encompasses discussions on ‘wrong man’ cases, with an emphasis on false confessions. Although false confessions remain one of the widely studied causes of wrongful convictions, they remain counterintuitive. A central issue in false confessions is that people, being rational, find it impossible to comprehend how people would confess to crimes they did not commit. Author David Karr Shipler wrote, ‘intuition holds that the innocent do not make false confessions’.1 At the heart of this statement is the assumption that no one engages in self-destructive behaviour. Some commentators have attributed the reasons for false confessions to mental illnesses or coercion by law enforcement officers. This paper agrees with the latter and will consider in-depth the causes of false confessions, including the investigative methods by which these confessions are elicited. As a result of the analysis, this paper will recommend that all countries, particularly Singapore, record custodial interrogations. While Singapore has implemented new changes such as recording statements in the form of audiovisuals for selected offences, these have not wholly guaranteed the absence of false confessions and wrongful convictions. Essentially, this paper is written with three purposes in mind: (a) to examine the extent of miscarriages of justice caused by false confessions and wrongful convictions; (b) to analyse the criminal justice system in Singapore in the context of obtaining statements from accused persons and the admissibility of such statements; and finally (c) to suggest that serious considerations should be accorded to recording custodial interrogations in Singapore as to enable a more adjudicated process which will, in turn, reduce false confessions and wrongful convictions

Economic life cycle assessment of aeration blowers used in waste water treatment systems

Economic Life Cycle Assessment of Aeration Blowers used in Waste Water Treatment systems A substantial amount of energy is needed in water supply and treatment systems to convert the unprocessed water into safe drinking water or to purify wastewater prior to discharge to the environment. There is lot of water and energy lost in the process of collection, discharge and delivery of the treated drinking water as well. Therefore the energy and water consumption by these systems have an indirect effect on the local municipality in terms of high energy consumption and in permissive waste of water. Thus, an exhaustive research and life cycle analysis must be carried out in each process of water treatment to extenuate energy and water inefficiencies in the system. Thus new methodologies to improve the efficiency of mundane systems have to be encouraged. This study focuses on economic life cycle analysis on water treatment systems to attain sustainability in the economic pursuit of water treatment bodies in US. Life cycle assessment concentrates on techniques to access environment impacts on system associated with all the stages of a product’s life form. Life cycle assessment helps in analyzing and quantifying the flaws and recommending methods to overcome them. Thus in this study we focus on evaluating the effect on energy consumption, cost etc. for two different (competing) blower technologies used by the August County Service Authority (ACSA), Virginia. The two types of blowers are: 1. Centrifugal blowers – an older, established technology supplied by Hipon 2. Turbo blowers – a relatively recent technology (to US) supplied by Neuros Keywords: Life Cycle Assessment, Centrifugal, Turbo, Blowers

An Engineered Nonsense \u3cem\u3eURA3\u3c/em\u3e Allele Provides a Versatile System to Detect the Presence, Absence and Appearance of the [em\u3ePSI\u3c/em\u3e\u3csup\u3e+\u3c/sup\u3e] Prion in \u3cem\u3eSaccharomyces cerevisiae\u3c/em\u3e

Common methods to identify yeast cells containing the prion form of the Sup35 translation termination factor, [PSI+], involve a nonsense suppressor phenotype. Decreased function of Sup35p in [PSI+] cells leads to readthrough of certain nonsense mutations in a few auxotrophic markers, for example, ade1-14. This readthrough results in growth on adenine deficient media. While this powerful tool has dramatically facilitated the study of [PSI+], it is limited to a narrow range of laboratory strains and cannot easily be used to screen for cells that have lost the [PSI+] prion. Therefore we have engineered a nonsense mutation in the widely used URA3 gene, termed the ura3-14 allele. Introduction of the ura3-14 allele into an array of genetic backgrounds, carrying a loss-of-function URA3 mutation and [PSI+], allows for growth on media lacking uracil, indicative of decreased translational termination efficiency. This ura3-14 allele is able to distinguish various forms of the [PSI+] prion, called variants and is able to detect the de novo appearance of [PSI+] in strains carrying the prion form of Rnq1p, [PIN+]. Furthermore, 5-fluoorotic acid, which kills cells making functional Ura3p, provides a means to select for [psi−] derivatives in a population of [PSI+] cells marked with the ura3-14 allele, making this system much more versatile than previous methods

Changes in the production of tobacco and its impact on peasant farming in the Jaffna Peninsula, Ceylon

This thesis is concerned with an effort to apply the micro-geographic and historical approaches to the study of the changes that have occurred in the system of agriculture in the Jaffna Peninsula, in Ceylon, over a period of four to five centuries. An attempt will also be made to describe the farming operations as they are found today. Further, the factors that seem to preclude the farmers from adopting certain innovations in the system of agriculture, even though changes in the demand for tobacco necessitate some changes in the system, will be indicated

Investigation Study on the Strength Properties of Local Sand as Proppant

This project presents literature review and experimental work on local sands for possible use as proppant especially sand samples from the Terengganu coastal area. Currently, there is no local proppant manufacturer in Malaysia and Malaysia has to import proppant from overseas especially from United States and Canada. This leads to the high well stimulation costs in Malaysia. If the local sand in Malaysia qualifies to be used as proppant, Malaysia can produce its local proppant manufacturer which may reduce the well stimulation costs in Malaysia. Thus, in this project, the characteristics of the Terengganu local sand will be examined and compared to the characteristics of the existing proppant used in current market. The present study found that the size distribution, sphericity, turbidity and bulk density of Terengganu sands are at similarity with some of commercial proppants. Thus, in this project additional research and experimental work will be done to further identify the possible use of Terengganu sand as proppant. These samples will be tested upon the sphericity, roundness, bulk density, shear strength, turbidity, acid solubility and suspension of particles in the slurry

\u3cem\u3eDrosophila\u3c/em\u3e Vitelline Membrane Assembly: A Critical Role for an Evolutionarily Conserved Cysteine in the “VM domain” of sV23

The vitelline membrane (VM), the oocyte proximal layer of the Drosophila eggshell, contains four major proteins (VMPs) that possess a highly conserved “VM domain” which includes three precisely spaced, evolutionarily conserved, cysteines (CX7CX8C). Focusing on sV23, this study showed that the three cysteines are not functionally equivalent. While substitution mutations at the first (C123S) or third (C140S) cysteines were tolerated, females with a substitution at the second position (C131S) were sterile. Fractionation studies showed that sV23 incorporates into a large disulfide linked network well after its secretion ceases, suggesting that post-depositional mechanisms are in place to restrict disulfide bond formation until late oogenesis, when the oocyte no longer experiences large volume increases. Affinity chromatography utilizing histidine tagged sV23 alleles revealed small sV23 disulfide linked complexes during the early stages of eggshell formation that included other VMPs, namely sV17 and Vml. The early presence but late loss of these associations in an sV23 double cysteine mutant suggests that reorganization of disulfide bonds may underlie the regulated growth of disulfide linked networks in the vitelline membrane. Found within the context of a putative thioredoxin active site (CXXS) C131, the critical cysteine in sV23, may play an important enzymatic role in isomerizing intermolecular disulfide bonds during eggshell assembly

IN VIVO AMELIORATIVE POTENTIAL OF CAFFEIC ACID AGAINST HEPATOTOXICITY AND NEPHROTOXICITY INDUCED BY MERCURIC CHLORIDE IN ALBINO WISTAR RATS

Objective: The current experimental study is designed to scrutinize the possible defensive effect of caffeic acid (CA) against mercury-induced hepatotoxicity in male rats. Methods: During the treatment periods, a sub-lethal dose of HgCl2 (1.29 mg/kg body weight) was given to rats for 15 days through oral administration and the CA was administrated for 15 days, on mercuric intoxicated rats were observed. After completing the programmed period of experimental work, the blood was drawn through a micro glass tube in the ocular region and separated the serum by centrifuge. Results: The subsequent serum enzymes were analyzed as the alkaline phosphatase (ALP), alanine transferase (ALT), aspartate transaminase (AST), and lactate dehydrogenase (LDH). Further, the bilirubin, albumin, total cholesterol, urea, and creatinine levels were also noticed in the blood serum of both normal and treated rats. CA is one of the well-known phenolic compounds, and a strong antioxidant helps to prevent oxidative damage and reducing oxidative stress. The biological action of liver biomarker enzymes such as ALT, AST, ALP, and LDH was significantly enhanced and at the same time the drastic increased in the level of albumin was all together decreased. The level of bilirubin, total cholesterol, urea, and creatinine was significantly increased in HgCl2 intoxicated rats. When the treatment of CA on mercury intoxicated rats for 15 days (5 mg/kg body weight), in the serum enzymes (ALT, AST, ALP, and LDH) also declined to near normal level. The level of bilirubin, total cholesterol, urea, and creatinine activities was also significantly declined to near normal level when compared to mercury-treated group. The level of albumin was significantly enhanced. The CA alone treatment showed the enhanced antioxidant levels and not any alteration in the levels of biochemical parameters when compared to control. Conclusion: These observations of the present experimental work demonstrated the detoxify effects and defensive effect of CA against HgCl2 toxicity in liver tissue