Self-reported reasons for on-duty sleepiness among commercial airline pilots

Experimental and epidemiological research has shown that human sleepiness is determined especially by the circadian and homeostatic processes. The present field study examined which work-related factors airline pilots perceive as causing on-duty sleepiness during short-haul and long-haul flights. In addition, the association between the perceived reasons for sleepiness and actual sleepiness levels was examined, as well as the association between reporting inadequate sleep causing sleepiness and actual sleep-wake history. The study sample consisted of 29 long-haul (LH) pilots, 28 short-haul (SH) pilots, and 29 mixed fleet pilots (flying both SH and LH flights), each of whom participated in a 2-month field measurement period, yielding a total of 765 SH and 494 LH flight duty periods (FDPs) for analyses (FDP, a period between the start of a duty and the end of the last flight of that duty). The self-reports of sleepiness inducers were collected at the end of each FDP by an electronic select menu. On-duty sleepiness was rated at each flight phase by the Karolinska Sleepiness Scale (KSS). The sleep-wake data was collected by a diary and actigraph. The results showed that "FDP timing" and "inadequate sleep" were the most frequently reported reasons for on-duty sleepiness out of the seven options provided, regardless of FDP type (SH, LH). Reporting these reasons significantly increased the odds of increased on-duty sleepiness (KSS >= 7), except for reporting "inadequate sleep" during LH FDPs. Reporting "inadequate sleep" was also associated with increased odds of a reduced sleep-wake ratio (total sleep time/amount of wakefulnessPeer reviewe

Management Approach : The Virtuous Corporation as a Moral Agent for Sustainable Development

This chapter examines the corporation as a moral agent for sustainable development. While sustainable development in business organizations can be argued from utility-and duty-based ethical theories, it is suggested that virtue-based ethics is needed to develop a moral agency for sustainable development, as it focuses on the organizational character. In addition, it is proposed that the biosphere (the global sum of all ecosystems) is accepted as the ultimate principal for all planetary agents to avoid an anthropocentric and only inward-looking position typical for ethical theories. Thus, a business organization can work as a nexus for virtue and develop a moral agency that contributes to the well-being of the biosphere and all of its members.Peer reviewe

Lukemaan opettamisen menetelmän valinta

Tiivistelmä. Kandidaatintyön kirjallisuuskatsausosassa muodostimme viitekehyksen luku- ja kirjoitustaidosta, lukemaan opettamisesta ja KÄTS- sekä LPP-menetelmistä. Viitekehyksen ensimmäisessä kappaleessa määrittelimme luku- ja kirjoitustaidon termit, perehdyimme lukutaidon kehitykseen sekä kielelliseen ja kognitiiviseen kehitykseen. Kappaleessa paneuduimme myös motivaation syntymiseen ja toimivaan opetusympäristöön. Seuraavassa kappaleessa käsittelimme lukemaan opettamisen menetelmien jakautumista synteettisiin ja analyyttisiin menetelmiin. Viitekehyksen viimeisissä kappaleissa tarkastelimme käytetyimpiä lukemaan opettamisen menetelmiä eli KÄTS- ja LPP-menetelmää. Viitekehyksen tarkoituksena on perehtyä tarkemmin lukemaan opettamiseen ja siinä käytettyihin menetelmiin. Työn kvalitatiivisessa tutkimuksessa tarkastelemme ensimmäisen luokan opettajien kokemuksia lukemaan opettamisen menetelmän valinnasta ja valintaan johtaneista syistä. Tutkimus toteutettiin sähköisellä kyselylomakkeella, johon valitsimme mahdollisimman selkeät ja helposti vastattavat kysymykset. Kyselyyn vastasi viisi ensimmäisen luokan opettajaa, jotka kertoivat omien kokemusten perusteella miten päätyvät valitsemaan käyttämänsä opetusmenetelmän. Tuloksista selviää, että haastatteluun osallistuneet opettajat käyttävät pääsääntöisesti KÄTS-menetelmää lukemaan opettamisessa. Menetelmä sopii hyvin käytettäväksi suomen kielessä ja siihen löytyy paljon valmista opetusmateriaalia. Menetelmän avulla eriyttäminen molempiin suuntiin onnistuu vaivatta

Bound states of 3He at the edge of a 4He drop on a cesium surface

We show that small amounts of 3He atoms, added to a 4He drop deposited on a flat cesium surface at zero temperature, populate bound states localized at the contact line. These edge states show up for drops large enough to develop well defined surface and bulk regions together with a contact line, and they are structurally different from the well-known Andreev states that appear at the free surface and at the liquid-solid interface of films. We illustrate the one-body density of 3He in a drop with 1000 4He atoms, and show that for sufficiently large number of impurities, the density profiles spread beyond the edge, coating both the curved drop surface and its flat base and eventually isolating it from the substrate.Comment: 10 pages and 7 figures. Submitted to PR

Effect of Thiamine Status on Probability of Lake Ontario Chinook Salmon Spawning in the Upper and Lower Sections of Salmon River, New York

Consumption of thiaminase-containing forage fishes reduces egg and muscle thiamine content and impairs the spawning migration of Cayuga Lake (New York) rainbow trout Oncorhynchus mykiss. Because some Chinook salmon O. tshawytscha from Lake Ontario have been shown to produce eggs low in thiamine, we examined the relationship between the migration of Chinook salmon and the thiamine content of their eggs spawned in the lower and upper sections of the Salmon River, a major tributary to Lake Ontario, in 2003–2006. Eggs from the upper section of the river were collected from 79 salmon returning to the state hatchery 25 river kilometers from the mouth. Eggs from 25 salmon in the lower section were collected from redds or females angled on redds approximately 1–3 km from the mouth. For all years combined, we found the mean thiamine concentration in eggs spawned in the lower section to be significantly lower than that for eggs spawned in the upper section; however, the annual differences in thiamine content of eggs between the upper and lower sections were significant only in 2003 and 2006. Binary logistic regression showed that the odds of spawning in the upper section was increased by 96% (95% confidence interval, 21–217%) for every nanomole of increase in the thiamine content of eggs. Therefore, the migratory achievement of Chinook salmon was significantly dependent on their thiamine status

Poly(β-amino ester)–DNA complexes: Time-resolved fluorescence and cellular transfection studies

A large number of different polymers have been developed and studied for application as DNA carriers for non-viral gene delivery, but the DNA binding properties are not understood. This study describes the efficiency of nanoparticle formation by time-resolved fluorescence measurements for poly(β-amino esters), cationic biodegradable polymers with DNA complexation and transfection capability. From the large library of poly(β-amino esters) ten polymers with different transfection efficacies were chosen for this study. The binding constants for nanoparticle formation were determined and compared to with the same method. Although the DNA binding efficiency of the amine groups are similar for both types of polymers, the overall binding constants are an order of magnitude smaller for poly(β-amino esters) than for 25 kDa polyethylenimines, yet poly(β-amino esters) show comparable DNA transfection efficacy with polyethylenimines. Within this series of polymers the transfection efficacy showed increasing trend in association with relative efficiency of nanoparticle formation.Academy of FinlandNational Institutes of Health (U.S.) (Grant CA132091)National Institutes of Health (U.S.) (Grant CA115527

Wetting transitions of Ne

We report studies of the wetting behavior of Ne on very weakly attractive surfaces, carried out with the Grand Canonical Monte Carlo method. The Ne-Ne interaction was taken to be of Lennard-Jones form, while the Ne-surface interaction was derived from an ab initio calculation of Chizmeshya et al. Nonwetting behavior was found for Li, Rb, and Cs in the temperature regime explored (i.e., T < 42 K). Drying behavior was manifested in a depleted fluid density near the Cs surface. In contrast, for the case of Mg (a more attractive potential) a prewetting transition was found near T= 28 K. This temperature was found to shift slightly when a corrugated potential was used instead of a uniform potential. The isotherm shape and the density profiles did not differ qualitatively between these cases.Comment: 22 pages, 12 figures, submitted to Phys. Rev.

To wet or not to wet: that is the question

Wetting transitions have been predicted and observed to occur for various combinations of fluids and surfaces. This paper describes the origin of such transitions, for liquid films on solid surfaces, in terms of the gas-surface interaction potentials V(r), which depend on the specific adsorption system. The transitions of light inert gases and H2 molecules on alkali metal surfaces have been explored extensively and are relatively well understood in terms of the least attractive adsorption interactions in nature. Much less thoroughly investigated are wetting transitions of Hg, water, heavy inert gases and other molecular films. The basic idea is that nonwetting occurs, for energetic reasons, if the adsorption potential's well-depth D is smaller than, or comparable to, the well-depth of the adsorbate-adsorbate mutual interaction. At the wetting temperature, Tw, the transition to wetting occurs, for entropic reasons, when the liquid's surface tension is sufficiently small that the free energy cost in forming a thick film is sufficiently compensated by the fluid- surface interaction energy. Guidelines useful for exploring wetting transitions of other systems are analyzed, in terms of generic criteria involving the "simple model", which yields results in terms of gas-surface interaction parameters and thermodynamic properties of the bulk adsorbate.Comment: Article accepted for publication in J. Low Temp. Phy

Prewetting transitions of Ar and Ne on alkali metal surfaces

We have studied by means of Density-Functional calculations the wetting properties of Ar and Ne adsorbed on a plane whose adsorption properties simulate the Li and Na surfaces. We use reliable ab-initio potentials to model the gas-substrate interactions. Evidence for prewetting transitions is found for all the systems investigated and their wetting phase diagrams are calculated.Comment: 6 pages, 8 figures, submitted for publication in Phys. Rev.