A study of the testing and employment procedures used for initial employment of salespeople in one hundred thirty-five retail stores

Thesis (Ed. M.)--Boston University, 195

Museum Collections Management Systems: One Size Does Not Fit All

Collections management software companies claim their product can be used for any type of collection or museum. While this is true to some extent, in actuality, they are better suited for some types of collections and do not cover the others as well. Particular collections management databases have aspects that are better suited for certain types of collections and an individual museum\u27s needs. Each system\u27s particular combination of features and characteristics may make it a better fit for some museums\u27 needs and not for others. Recommendations for collections databases are constantly sought after on the American Association of Museum\u27s Registrar\u27s Committee Listserv. The systems to be reviewed in this study are: PastPerfect, TMS, EmbARK. Argus, Re:discovery, Vernon CMS, and KE-EMu. With all of these choices available selecting the right system for a museum can be an overwhelming task. What the right system is, however, will be different for every institution. What may be a near perfect fit for one institution could result in disaster and frustration for another

Museum Collections Management Systems: One Size Does Not Fit All

Collections management software companies claim their product can be used for any type of collection or museum. While this is true to some extent, in actuality, they are better suited for some types of collections and do not cover the others as well. Particular collections management databases have aspects that are better suited for certain types of collections and an individual museum\u27s needs. Each system\u27s particular combination of features and characteristics may make it a better fit for some museums\u27 needs and not for others. Recommendations for collections databases are constantly sought after on the American Association of Museum\u27s Registrar\u27s Committee Listserv. The systems to be reviewed in this study are: PastPerfect, TMS, EmbARK. Argus, Re:discovery, Vernon CMS, and KE-EMu. With all of these choices available selecting the right system for a museum can be an overwhelming task. What the right system is, however, will be different for every institution. What may be a near perfect fit for one institution could result in disaster and frustration for another

Improved very short-term spatio-temporal wind forecasting using atmospheric regimes

We present a regime‐switching vector autoregressive method for very short‐term wind speed forecasting at multiple locations with regimes based on large‐scale meteorological phenomena. Statistical methods for wind speed forecasting based on recent observations outperform numerical weather prediction for forecast horizons up to a few hours, and the spatio‐temporal interdependency between geographically dispersed locations may be exploited to improve forecast skill. Here, we show that conditioning spatio‐temporal interdependency on “atmospheric modes” derived from gridded numerical weather data can further improve forecast performance. Atmospheric modes are based on the clustering of surface wind and sea‐level pressure fields, and the geopotential height field at the 5000‐hPa level. The data fields are extracted from the MERRA‐2 reanalysis dataset with an hourly temporal resolution over the UK; atmospheric patterns are clustered using self‐organising maps and then grouped further to optimise forecast performance. In a case study based on 6 years of measurements from 23 weather stations in the UK, a set of 3 atmospheric modes are found to be optimal for forecast performance. The skill of 1‐ to 6‐hour‐ahead forecasts is improved at all sites compared with persistence and competitive benchmarks. Across the 23 test sites, 1‐hour‐ahead root mean squared error is reduced by between 0.3% and 4.1% compared with the best performing benchmark and by an average of 1.6% over all sites; the 6‐hour‐ahead accuracy is improved by an average of 3.1%

Oral absorption of PEG-coated versus uncoated gold nanospheres: does agglomeration matter?

BACKGROUND: Particle size is thought to be a critical factor affecting the bioavailability of nanoparticles following oral exposure. Nearly all studies of nanoparticle bioavailability focus on characterization of the primary particle size of the material as supplied or as dosed, and not on agglomeration behavior within the gastrointestinal tract, which is presumably most relevant for absorption. METHODS: In the study reported here, snapshots of agglomeration behavior of gold nanospheres were evaluated in vivo throughout the gastrointestinal tract using transmission electron microscopy. Agglomeration state within the gastrointestinal tract was then used to help explain differences in gastrointestinal particle absorption, as indicated by tissue levels of gold detected using inductively coupled plasma mass spectrometry. Mice were dosed (10 mg/kg) with either 23 nm PEG-coated or uncoated gold nanospheres. RESULTS: Transmission electron microscopy demonstrates that PEG-coated gold nanoparticles can be observed as primary, un-agglomerated particles throughout the gastrointestinal tract and feces of dosed animals. In contrast, uncoated gold nanoparticles were observed to form agglomerates of several hundred nanometers in all tissues and feces. Inductively coupled plasma mass spectrometry shows significantly higher levels of gold in tissues from animals dosed with PEG-coated versus uncoated 23 nm gold nanoparticles. Retention of particles after a single oral gavage was also very high, with all tissues of animals dosed with PEG-coated particles having detectable levels of gold at 30 days following exposure. CONCLUSIONS: Qualitative observation of these particles in vivo shows that dispersed PEG-coated particles are able to reach the absorptive tissues of the intestine while agglomerated uncoated particles are sequestered in the lumen of these tissues. However, the large differences observed for in vivo agglomeration behavior were not reflected in oral absorption, as indicated by gold tissue levels. Additional factors, such as surface chemistry, may have played a more important role than in vivo particle size and should be investigated further

A risk assessment method for "Eurobalise" fastening system: managing the sensor/sleeper interaction in the high-speed railway infrastructure

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Mussel-inspired 3D fiber scaffolds for heart-on-a-chip toxicity studies of engineered nanomaterials

Due to the unique physicochemical properties exhibited by materials with nanoscale dimensions, there is currently a continuous increase in the number of engineered nanomaterials (ENMs) used in consumer goods. However, several reports associate ENM exposure to negative health outcomes such as cardiovascular diseases. Therefore, understanding the pathological consequences of ENM exposure represents an important challenge, requiring model systems that can provide mechanistic insights across different levels of ENM-based toxicity. To achieve this, we developed a mussel-inspired 3D microphysiological system (MPS) to measure cardiac contractility in the presence of ENMs. While multiple cardiac MPS have been reported as alternatives to in vivo testing, most systems only partially recapitulate the native extracellular matrix (ECM) structure. Here, we show how adhesive and aligned polydopamine (PDA)/polycaprolactone (PCL) nanofiber can be used to emulate the 3D native ECM environment of the myocardium. Such nanofiber scaffolds can support the formation of anisotropic and contractile muscular tissues. By integrating these fibers in a cardiac MPS, we assessed the effects of TiO2 and Ag nanoparticles on the contractile function of cardiac tissues. We found that these ENMs decrease the contractile function of cardiac tissues through structural damage to tissue architecture. Furthermore, the MPS with embedded sensors herein presents a way to non-invasively monitor the effects of ENM on cardiac tissue contractility at different time points. These results demonstrate the utility of our MPS as an analytical platform for understanding the functional impacts of ENMs while providing a biomimetic microenvironment to in vitro cardiac tissue samples. Graphical Abstract Heart-on-a-chip integrated with mussel-inspired fiber scaffolds for a high-throughput toxicological assessment of engineered nanomaterials

Evolution of syngamy

Sex is normally thought to function as a mechanism that injects heritable genetic variation into populations. But genetic mixing does not occur with self-fertilizers, and self-fertilizers have probably persisted since early eukaryotic evolution. I discuss the purpose of sex without genetic mixing and proffer that sex is a conservative mechanism that decreases heritable genetic variation. Syngamy (nuclear/pronuclear fusion/association + "mixing" of chromosomes) is a lesser-understood and lesser-studied aspect of sex. I propose that syngamy is a type of cell division that evolved from meiosis. In most metazoans, diploidy is restored via a cell division rather than through fusion event. I propose that meiosis and syngamy are pleiotropically controlled, and that they hypothetically share at least two homologous features that neither share with mitosis: (1) the requirement for membrane fusion/association, and (2) some products of the division are ontogenetically discarded

Research and Definition of Car Accident Scenarios for Roadway Safety Management of S:s: 372 "Telesina".

The present paper has been developed on traffic, car accident and geometric data surveyed on the 61 kms of the italian rural road SS (Strada Statale) 372 “Telesina”. The SS 372 starts from the motorway exit of Caianello, located on the Rome - Naples highway and ends in the town of Benevento. It has a variable cross section but in average it is about 9 m wide. The road alignment is typical of rural roads running in the hilly countryside of Campania region, southern Italy. The vertical alignment is made with several crests among upgrades but their values are lower than 3,5%; in the final part of the track heading Benevento there is just one 7% upgrade. All along the track there are many motorway exits made on different levels with small lenght acceleration and deceleration lanes. Car accident data related to a 11 year period ranging from 1993 to 2003 have been collected and analysed from Police reports. The resulting database is made of about 180 accidents. The ANAS statistics on 3 sections of the road track have been collected too, being ANAS the Italian society deputed to the management of most part of rural roads. So, it has been possible to share the whole track in 3 parts. The ADT (Average Daily Traffic) has been supposed to be constant within each part of the road. The preliminary general analyses done on the whole track showed not so high accident indexes. Nevertheless, the successive scenario research showed some specific matters. First, a database of the road has been built. The database has been shared in three parts: 1) geometric data; 2) traffic data; 3) accident data. The first part has been built with the help of the existing topographic data: the whole track has been summarized with specific regard to horizontal and vertical alignment and location of motorway exits. The second part has been built on ANAS data as previously stated. The third part has been built on the police data. Accident location, traffic and road pavement conditions have been filed. Finally, a matrix data in which the following quantities have been associated to every accident has been built: “heading (to Benevento or Caianello) of the car which caused the accident, extracted from part 3; light conditions (day or night) at the moment of the accident, extracted from part 3; road pavement conditions (wet or dry) at the moment of the accident, extracted from part 3; horizontal alignment (curve or tangent), vertical alignment (positive, negative or plan) in the area of the accident, extracted from part 1 and finally the sight distance of the point in which the car accident happened (yes or no) calculated with informations provided from parts 1 and 3. Part 2 data have been just used to share the road into three homogeneous traffic conditions. Not all components have been used to build scenarios. Finally, 96 different possible scenarios have been built. As soon as each scenario has been characterized on the temporal and spatial point of view their hazardousness has been evaluated with the accident index. Results showed that all 3 most dangerous scenarios included the component “lack of passing sight distance”. Details showed that the first and most dangerous scenario is made with the following components: “daytime, wet, curve, lack of passing sight distance”; the second one “daytime, dry, curve, lack of passing sight distance”. So, it seems clear that the component ”lack of passing sight distance” has a prevalent influence on the hazardousness of scenarios; in order to improve safety it should be necessary to work on this component for instance by enlarging the shoulders of the road or making adequate excavation in curve