6,638 research outputs found
Beyond Sufficiency: G.A. Cohen's Community Constraint on Luck Egalitarianism
G. A. Cohen conceptualizes socialism as luck egalitarianism constrained by a community principle. The latter mitigates certain inequalities to achieve a shared common life. This article explores the plausibility of the community constraint on inequality in light of two related problems. First, if it is voluntary, it fails as a response to “the abandonment objection” to luck egalitarianism, as it would not guarantee imprudent people sufficient resources to avoid deprivation and to function as equal citizens in a democratic society. Contra Cohenite socialism, this appears unjust. Second, if it is instead enforced, coercive equalization beyond sufficiency-constrained luck egalitarianism, which is possibly necessary to achieve a shared common life, seems to require unjustified restrictions on liberty. I therefore argue that the constraint is most plausibly specified as requiring enforcement of sufficiency and only voluntary equalization thereafter. I also note, skeptically, why this constraint might be morally preferable to a purely sufficientarian alternative
Welding and post weld heat treatment of 2.25%Cr-1%Mo steel
The current standard practice when welding 2.25Cr-1Mo steel is to use preheat and post welding heat treatment (PWHT) to improve weldability. The research outlined in this thesis is an investigation of the microstructure and mechanical properties of weldments of 2.25Cr-1Mo steel before and after the application of preheat and/or post weld heat treatment. Trial welds and simulated coarse grained heat affected zone (CGHAZ) material were mechanically tested and etallurgically examined before and after welding and PWHT. The pre-heat investigation involved 3.8 mm and 7.1 mm thick tubes, welded with pre-heats of 25 °C, 50 °C and the standard 150 °C. These samples were then mechanically tested to AS3992. The PWHT investigation was carried out on 12 mm thick tube and 16 and 26 mm thick plate samples. After welding, the samples were heated to a simulated service temperature of 550 °C for up to 10 h and PWHT at 700 °C. These samples were then compared in terms of microstructure and hardness. To enable mechanical testing of HAZ material, simulated HAZ material was produced. These controlled cooling samples also enabled monitoring of the transformation behaviour to produce a CCT diagram and comparison of the transformation products with the trial welds. The results of this experimental program showed that pre-heating thin tubes in the range 25-150 °C had no noticeable effect on their properties. It is however expected that the influence of the pre-heat temperature would be limited to the root pass, as the higher interpass temperature would override any effect of the pre-heat temperture. The welds made in 12 mm and 16 mm thick material also showed negligible difference in their response to short-term ageing and PWHT. The results from the 26 mm sample however showed higher hardness and a different microstructure to those of other plate thicknesses. Thus no evidence based on mechanical properties and microstructures was found to support the specification in the Australian Standard AS4458 for pre-heat 7 temperatures above 25 °C when welding tubes up to 7.1 mm thick. Furthermore, although the Australian Standards do not require PWHT for 12 mm tube, but specify PWHT for 16 mm plate, the present results do not provide a basis for the need for PWHT in either case. These conclusions are drawn within the context that the experimental welds were made under low restraint conditions and high restraint in industrial practice could affect weldment integrity through the development of high residual stresses, distortion and/or HAZ cracking
Arenavirus Transcription, Replication, and Interaction with Host-Cellular Components
Arenaviruses are enveloped negative-strand RNA viruses that cause significant human disease. Despite decades of research, it is still unclear how these viruses establish a lifelong, asymptomatic infection in their rodent hosts while infection of humans often results in severe disease. Unable to enter a state of bona fide latency, the transcription and replication of the viral genomic RNA is likely highly regulated in time and subcellular space. Moreover, we hypothesize that the viral nucleoprotein (NP), responsible for the encapsidation of the viral RNA and the most highly expressed viral gene product, plays a key role in the regulation of the viral gene expression program. Further, exploring host-virus interactions may elucidate the basic aspects of arenavirus biology and how they cause such severe disease in humans. To explore these questions in greater detail, this dissertation has pursued three main avenues.
First, to better understand lymphocytic choriomeningitis mammarenavirus (LCMV) genome replication and transcription at the single-cell level, we established a high-throughput, single-molecule (sm)FISH image acquisition and analysis pipeline and followed viral RNA species from viral entry through the late stages of persistent infection in vitro. This work provided support for a cyclical model of persistence where individual cells are initially transiently infected, clear active infection, and become re-infected from neighboring reservoir cells within the population.
Second, we used FISH to visualize viral genomic RNA to describe the subcellular sites where LCMV RNAs localize during infection. We observed that, viral RNA concentrates in large subcellular structures located near the cellular microtubule organizing center and colocalizes with the early endosomal marker Rab5c and the viral glycoprotein in a proportion of infected cells. We propose that the virus is using the surface of a cellular membrane bound organelle as a site for the pre-assembly of viral components including genomic RNA and viral glycoprotein prior to their transport to the plasma membrane where new particles will bud.
Last, we used mass spectrometry to identify human proteins that interact with the NPs of LCMV and Junín mammareanavirus (JUNV) strain Candid #1. We provided a detailed map of the host machinery engaged by arenavirus NPs, and in particular, showed that NP associates with the double-stranded RNA (dsRNA)-activated protein kinase (PKR), a well-characterized antiviral protein that inhibits cap-dependent protein translation initiation via phosphorylation of eIF2α. We demonstrated that JUNV antagonizes the antiviral activity of PKR completely, effectively abrogating the antiviral activity of this surveillance pathway.
In sum, the work composing this dissertation has given us fresh insight into how arenaviruses establish and maintain persistence; the nature of the subcellular site where viral genomic RNA is transcribed, replicated, and assembled with other viral components; and a global view of the cellular machinery hijacked by the viral nucleoprotein. This work improves our basic understanding of the arenavirus life cycle and may suggest novel antiviral therapeutic targets that could be exploited in the future
The Gravamen of \u3cem\u3eWisconsin v. Yoder\u3c/em\u3e at Fifty, 1972-2022
After an arduous journey of more than four years that Wallace Miller, Jonas Yoder, and Adin Yutzy began in New Glarus, WI, the U.S. Supreme Court handed down its landmark decision in Wisconsin v. Yoder , 406 U.S. 205 on May 15, 1972. In affirming the Supreme Court of Wisconsin’s decision reversing the convictions of Miller, Yoder, and Yutzy (Respondents) for violating the compulsory school attendance statute, the U.S. Supreme Court found that enforcement of the statute violated the Respondents’ rights pursuant to the free exercise of religion clause conferred by the First Amendment and made applicable to the states through the Fourteenth Amendment of the United States Constitution. Chief Justice Warren Burger’s majority opinion created a four part “Compelling Interest Test.” First, a party must demonstrate a sincere and truly religious claim. Next, the party must show that the government action is injurious to religious practice. The burden then shifts to the State to show that the State action is necessitated by a Compelling State Interest. Finally, the State must demonstrate that no other alternative means is available to make the contemplated action less burdensome to religious liberty (Ball 2003, 256). [First paragraph.
Pavlovian Processes in Consumer Choice: The Physical Presence of a Good Increases Willingness-to-Pay
This paper describes a series of laboratory experiments studying whether the form in which items are displayed at the time of decision affects the dollar value that subjects place on them. Using a Becker-DeGroot auction under three different conditions — (i) text displays, (ii) image displays, and (iii) displays of the actual items — we find that subjects' willingness-to-pay is 40-61 percent larger in the real than in the image and text displays. Furthermore, follow-up experiments suggest the presence of the real item triggers preprogrammed consummatory Pavlovian processes that promote behaviors that lead to contact with appetitive items whenever they are available
Carbon nanotube biosensors for detection of biomarkers in breast cancer cells.
Detection and profiling of circulating tumor cells (CTCs) is useful for cancer screening and for managing treatment of carcinoma patients. Label-free technologies aim to accomplish detection rapidly with small, simple micro and nano devices. Carbon nanotubes are favorable molecular sensors due to their unique properties. They have been widely investigated for immunosensing of cancer biomarkers as free proteins, but very little has been done to detect biomarkers in intact cells and much remains to be understood regarding the mechanism of their sensing. We have developed a simple carbon nanotube biosensor for epithelial cell adhesion molecule (EpCAM) for sensing EpCAM positive cells. Sensor fabrication steps involving minimal air exposure were employed which reduced random noise upon sample introduction to the device. Optimized sensors recognized specific interactions with EpCAM positive MCF-7 cells and did not recognize EpCAM negative MCF-10A cells, producing the same characteristic signal as for blank phosphate buffered saline samples (no interaction). A two sample t-test found that the specific and nonspecific signals were significantly different, p = 0.0235. Specific binding signals are attributed to the combined binding events and negative cell membrane potential
Mechanically milled bulk nanocrystalline Nb(_3)Sn with improved superconducting properties in high magnetic fields
The upper critical field of binary Nb(_3)Sn has been increased by mechanical milling and Hot Isostatic Pressing (HIP'ing) pre-alloyed powder to form bulk nanocrystalline samples. Extensive investigation of milling parameters allowed optimization of sample yield, purity and microstructure. X-Ray Diffraction (XRD) and Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) data show that milling can produce amorphous Nb(_3)Sn whilst maintaining low contamination levels (< 0.4 wt. %). Nb(_3)Sn powder milled under an argon atmosphere using specially-manufactured niobium milling tools has been consolidated in a HIP at high pressure (2000 Bar) and a range of temperatures (450 - 850 С). ICP-MS analysis allowed restoration of the milled Nb(_3)Sn stoichiometry prior to powder consolidation. In-field variable-temperature resistivity and magnetic susceptibility measurements of these disordered high-purity bulk Nb(_3)Sn samples are presented. The critical temperature, Tс, of Nb(_3)Sn is depressed by milling, but the recovery in Tc with HIP temperature coincides with a systematic reduction in microstructural disorder. The relationship between upper critical field, B(_C2)(^0.5P)(0), and HIP temperature reaches a peak of 31.7 土 0.4 т at 700 С, ֊6 т higher than typical values for binary Nb(_3)Sn. The very high normal-state resistivity (200 ± 27 μΩ cm at 20 K) and low Scherrer grain size (70 nm) imply that this increase is due to a disordered nanocrystalline microstructure. To facilitate the investigation of the properties of technological Nb(_3)Sn over a large range of applied strain (-1 to +0.3 %), a procedure for attaching superconducting wires to Tİ-6A1-4V helical strain springs is also presented
Clarification and Disruption: The Effect of Gasperini v. Center for Humanities Inc. on the Erie Doctrine
Rationality under fire: the incorporation of emotion into rational choice
We are told that as many as 75% of soldiers did not return fire during World War II. Though there is some historical truth in this claim, what should be of greater interest is the controversy around it. The idea that would we do nothing in great physical danger, especially when there no cost to fight, challenges the very notion of what it means to be a rational human. As such, this thesis is less about the phenomena of combat passivity, than it is about the challenge it presents to rational choice theory, a challenge that it cannot survive. That we do not choose according to outcome but according to how we think we will feel is hardly a new idea. In its current state, however, emotion remains an irreducible 'black-‐box' for social theory, with terms like 'fear' and 'regret' being both ill-‐defined and culturally loaded. Drawing from a number of fields including therapeutic psychology, anthropology and the philosophy of emotion, this thesis proposes the precept cognito ergo sentio. Our thoughts always produce feelings. Even if we do not name them emotions, we choose based on these. This manifests in two reproducible ways: via schemas -‐ whether or not an event or object or experience or person 'fits' -‐ and by assignation, whether the self or other is, or will be, to blame for a schemic violation (or completion). This approach explains both irrational and rational choice, as well as the way in which we can imagine future feeling states within anticipated scenarios. In the case of violence and passivity, we will examine three such invocations: schemic breaks (lack of fit, or 'fear'), causal assignation of the self (or 'shame'), and causal assignation of the external (or 'anger'). Each of these thinking modalities generates a feeling which in turn determines a choice in the individual, whether to fight, freeze, slaughter, surrender or even break down
- …