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At a conference I attended not so long ago I suggested to someone who had just read a paper that beneath his apparent commitment to a kind of ethical relativism he was in fact an ethical absolutist. The person I was addressing seemed quite upset by my suggestion and proceeded to argue that my understanding of his paper was somewhat awry. This experience was not new to me. Having taught ethics and philosophy of education courses for many years, courses which have been taken by undergraduates and by members of the teaching profession, I know that if I ever say to those I teach that they are adopting or favouring an absolutist position, then, more than likely, they will regard my remark as something to be opposed and they will often suggest that there must be some misunderstanding on my part. Judging by my experiences, ‘absolutist’ is a label most undergraduates and teachers wish to disown, particularly at the outset of ethics and philosophy courses, even though many of these disowners seem to subscribe to absolutist positions on such issues as racism, rape and child abuse. In his book Ethics; Discovering Right and Wrong Louis P. Pojman, talking about his own findings in this area, makes it clear that my teaching experiences are not unique. Over a period of several years and in several universities Pojman found that most of the students who took his ethics or philosophy courses explicitly rejected absolutism and affirmed support for some kind of relativism even though several of these aspiring relativists subscribed to absolutist positions on various ethical matters (Pojman, 1990, 19).
Background: Contaminated surfaces within patient rooms and on shared equipment is a major driver of healthcare-acquired infections (HAIs). The emergence of Candida auris in the New York City metropolitan area, a multidrug-resistant fungus with extended environmental viability, has made a standardized assessment of cleaning protocols even more urgent for our multihospital academic health system. We therefore sought to create an environmental surveillance protocol to detect C. auris and to assess patient room contamination after discharge cleaning by different chemicals and methods, including touch-free application using an electrostatic sprayer. Surfaces disinfected using touch-free methods may not appear disinfected when assessed by fluorescent tracer dye or ATP bioluminescent assay. Methods: We focused on surfaces within the patient zone which are touched by the patient or healthcare personnel prior to contact with the patient. Our protocol sampled the over-bed table, call button, oxygen meter, privacy curtain, and bed frame using nylon-flocked swabs dipped in nonbacteriostatic sterile saline. We swabbed a 36-cm2 surface area on each sample location shortly after the room was disinfected, immediately inoculated the swab on a blood agar 5% TSA plate, and then incubated the plate for 24 hours at 36°C. The contamination with common environmental bacteria was calculated as CFU per plate over swabbed surface area and a cutoff of 2.5 CFU/cm2 was used to determine whether a surface passed inspection. Limited data exist on acceptable microbial limits for healthcare settings, but the aforementioned cutoff has been used in food preparation. Results: Over a year-long period, terminal cleaning had an overall fail rate of 6.5% for 413 surfaces swabbed. We used the protocol to compare the normal application of either peracetic acid/hydrogen peroxide or bleach using microfiber cloths to a new method using sodium dichloroisocyanurate (NaDCC) applied with microfiber cloths and electrostatic sprayers. The normal protocol had a fail rate of 9%, and NaDCC had a failure rate of 2.5%. The oxygen meter had the highest normal method failure rate (18.2%), whereas the curtain had the highest NaDCC method failure rate (11%). In addition, we swabbed 7 rooms previously occupied by C. auris–colonized patients for C. auris contamination of environmental surfaces, including the mobile medical equipment of the 4 patient care units that contained these rooms. We did not find any C. auris, and we continue data collection. Conclusions: A systematic environmental surveillance system is critical for healthcare systems to assess touch-free disinfection and identify MDRO contamination of surfaces.
This work aims at providing guidance through systematic experimental characterization for the design of 3D-printed scaffolds for potential orthopedic applications, focusing on fused deposition modeling with a composite of clinically available polycaprolactone (PCL) and β-tricalcium phosphate (β-TCP). First, we studied the effect of the chemical composition (0–60% β-TCP/PCL) on the scaffold’s properties. We showed that surface roughness and contact angle were, respectively, proportional and inversely proportional to the amount of β-TCP and that degradation rate increased with the amount of ceramic. Biologically, the addition of β-TCP enhanced proliferation and osteogenic differentiation of C3H10. Second, we systematically investigated the effect of the composition and the porosity on the 3D-printed scaffold mechanical properties. Both an increasing amount of β-TCP and a decreasing porosity augmented the apparent Young’s modulus of the 3D-printed scaffolds. Third, as a proof of concept, a novel multimaterial biomimetic implant was designed and fabricated for potential disc replacement.
Multibeam bathymetry and 3.5-kHz sub-bottom profiler data collected from the US icebreaker Healy in 2003 provide convincing evidence for grounded ice on the Chukchi Borderland off the northern Alaskan margin, Arctic Ocean. The data show parallel, glacially induced seafloor scours, or grooves, and intervening ridges that reach widths of 1000 m (rim to rim) and as much as 40 m relief. Following previous authors, we refer to these features as “megascale glacial lineations (MSGLs).” Additional support for ice grounding is apparent from stratigraphic unconformities, interpreted to have been caused by ice-induced erosion. Most likely, the observed sea-floor features represent evidence for massive ice-shelf grounding. The general ESE/WNW direction of the MSGLs, together with sediment, evidently bulldozed off the Chukchi Plateau, that is mapped on the western (Siberian) side of the plateau, suggests ice flow from the Canada Basin side of Chukchi Borderland. Two separate generations of glacially derived MSGLs are identified on the Chukchi Borderland from the Healy geophysical data. The deepest and oldest extensive MSGLs appear to be draped by sediments less than 5 m thick, whereas no sediment drape can be distinguished within the resolution of the sub-bottom profiles on the younger generation.
A spectral line survey for interstellar NH3 is being carried out using the 64-m telescopes at Parkes and Tidbinbilla. Both telescopes are equipped with K-band maser receivers yielding system temperatures below 100 K. The preliminary survey is being made with the Parkes antenna (beam = 1.35 arcmin), with follow-up mapping of the more interesting sources at Tidbinbilla (beam = 0.9 arcmin). The selected sources have in general been HII regions from the H2CO surveys made at Parkes. Statistical results from initial observations of the (1, 1), (2, 2), and (3, 3) lines in the preliminary survey are presented.
As part of an extensive southern survey of interstellar NH3 with the Parkes 64-m radio telescope (with a beamwidth of 81 arcsec), the (1, 1), (2, 2), and (3, 3) transitions have been observed towards the galactic centre molecular cloud G1.6-0.025. The cloud has an overall size of 10 arcmin, and contains several concentrations with differing velocities. It has several features also observed in other galactic centre clouds, e.g. high optical depths and kinetic temperatures above 50 K.
The Parkes 64-m antenna has been used to map ammonia emission in the (J,K = 1,1) and (J,K = 2,2) transitions toward molecular cloud complex NGC 6334. This complex contains a number of OH and H2O masers, HII regions and IR sources, and is a rich source of molecular line emission.
Distributions of observed and derived quantities are presented with a linear resolution of ∼ 1 pc. Velocity anomalies are present near the two OH masers NGC 6334A and B, and the source of ammonia emission located near the northernmost H2O maser is one of the most intense sources of NH3 emission in the Galaxy.
Cognitive radio (CR) has generated a lot of interest because of the promise of wide instantaneous bandwidths which will improve data rates. Current social trends suggest that CR nodes will ultimately be mobile and handheld. This produces a need for small wideband antennas. The Chu limit imposes a restriction on what is obtainable with passive matching. In this paper, it is shown how a negative impedance converter (NIC) can be used to broadband match a chassis antenna beyond what is obtainable with passive matching. It is also shown how to predict and overcome the instabilities which have limited the top frequency achievable with NICs. The noise and linearity performance of the NIC matched antenna is also shown.
Using unique daily fund-manager trade data, we examine the role of institutional trading in influencing firm performance. We show that short-horizon informed trading by multiple institutional investors effectively disciplines corporate management. Our focus is on short-term “swing” trades, sequences with three phases (e.g., buy-sell-buy). We find swing trades increase stock price informativeness, are profitable after costs, and improve market efficiency. This increase in stock price informativeness is associated with subsequent firm outperformance. Trades are most beneficial with optimal stock holdings that reflect the information acquisition incentives of investors as well as liquidity costs.
The McMurdo Dry Valleys of Antarctica are the largest ice-free region on the continent. These valleys contain numerous water bodies that receive seasonal melt from glaciers. For forty years, research emphasis has been placed on the larger water bodies, the permanent ice-covered lakes. We present results from the first study describing the geochemistry of ponds in the higher elevations of Taylor Valley. Unlike the lakes at lower elevations, the landscape on which these ponds lie is among the oldest in Taylor Valley. These upland ponds wax and wane in size depending on the local climatic conditions, and their ionic concentrations and isotopic composition vary annually depending on the amount of meltwater generated and their hydrologic connectivity. This study evaluates the impact of changes in summer climate on the chemistry of these ponds. Although pond chemistry reflects the initial meltwater chemistry, dissolution and chemical weathering within the stream channels, and possibly permafrost fluid input, the primary control is the dilution effect of glacier melt during warmer summers. These processes lead to differences in solute concentrations and ionic ratios between ponds, despite their nearby proximity. The change in size of these ponds over time has important consequences on their geochemical behaviour and potential to provide water and solutes to the subsurface.
Epidemiological evidence suggests that diets rich in fruit and vegetables decrease the risk of premature mortality from major clinical conditions, including cancer and heart disease. However, it is not yet clear which components or combination of components in fruit and vegetables are protective and what is their mechanism of action. Such scientific uncertainty does not seem to inhibit the marketing of a huge range of plant-based concoctions, promoted as ‘magic bullets’ for optimum health. For example, the purported health-giving properties of plant polyphenols represent a case in which enthusiastic marketing claims may far exceed the current scientific evidence. Even when good experimental evidence exists, results need to be interpreted with caution in relation to human health benefits, as polyphenols may have limited bioavailability and may also be extensively metabolised. In addition, some polyphenols can be toxic and mutagenic in some cell culture systems. Until more is known about the activity and metabolic fate of polyphenols in the body, it would be better for the consumer to increase fruit and vegetable intake, and also to be wary of claims that these compounds are a panacea for good health.
Language anxiety is a prevalent phenomenon in second language learning. This experiment examines the arousal of anxiety caused by the introduction of a video camera at various points in a vocabulary learning task. Seventy-two students of 1st-year university French were randomly assigned to one of four groups: (a) one group who had anxiety aroused during their initial exposure to the stimuli, (b) a second group who had anxiety aroused when they began to learn the meanings of the words, (c) a third group who had anxiety aroused when they were asked to produce the French word (when prompted with the English), and (d) a control group who did not experience anxiety arousal. Significant increases in state anxiety were reported in all three groups when the video camera was introduced, and concomitant deficits in vocabulary acquisition were observed. It is concluded that the stage at which anxiety arises has implications for any remedial action taken to reduce the effects of language anxiety.