An Empirical Investigation of the Predictors of Executive Career Success

The present study examined the degree to which demographic, human capital,motivational, organizational, and industry/region variables predicted executive career success. Career success was assumed to comprise objective (pay, ascendancy) and subjective (job satisfaction, career satisfaction) elements. Results obtained from a sample of 1,388 U.S.executives suggested that demographic, human capital, motivational, and organizational variables explained significant variance in objective career success and in career satisfaction. Particularly interesting were findings that educational level, quality, prestige, and degree type all predicted financial success. In contrast, only the motivational and organizational variables explained significant amounts of variance in job satisfaction. These findings suggest that the variables that lead to objective career success often are quite different from those that lead to subjectively defined success

Concept definition study for recovery of tumbling satellites. Volume 1: Executive summary, study results

The first assessment is made of the design requirements and conceptual definition of a front end kit to be transported on the currently defined Orbital Maneuvering Vehicle (OMV) and the Space Transportation System Shuttle Orbiter, to conduct remote, teleoperated recovery of disabled and noncontrollable, tumbling satellites. Previous studies did not quantify the dynamic characteristics of a tumbling satellite, nor did they appear to address the full spectrum of Tumbling Satellite Recovery systems requirements. Both of these aspects are investigated with useful results

Concept definition study for recovery of tumbling satellites. Volume 2: Supporting research and technology report

A number of areas of research and laboratory experiments were identified which could lead to development of a cost efficient remote, disable satellite recovery system. Estimates were planned of disabled satellite motion. A concept is defined as a Tumbling Satellite Recovery kit which includes a modular system, composed of a number of subsystem mechanisms that can be readily integrated into varying combinations. This would enable the user to quickly configure a tailored remote, disabled satellite recovery kit to meet a broad spectrum of potential scenarios. The capability was determined of U.S. Earth based satellite tracking facilities to adequately determine the orientation and motion rates of disabled satellites

Getting into hot water:sick guppies frequent warmer thermal conditions

Ectotherms depend on the environmental temperature for thermoregulation and exploit thermal regimes that optimise physiological functioning. They may also frequent warmer conditions to up-regulate their immune response against parasite infection and/or impede parasite development. This adaptive response, known as ‘behavioural fever’, has been documented in various taxa including insects, reptiles and fish, but only in response to endoparasite infections. Here, a choice chamber experiment was used to investigate the thermal preferences of a tropical freshwater fish, the Trinidadian guppy (Poecilia reticulata), when infected with a common helminth ectoparasite Gyrodactylus turnbulli, in female-only and mixed-sex shoals. The temperature tolerance of G. turnbulli was also investigated by monitoring parasite population trajectories on guppies maintained at a continuous 18, 24 or 32 °C. Regardless of shoal composition, infected fish frequented the 32 °C choice chamber more often than when uninfected, significantly increasing their mean temperature preference. Parasites maintained continuously at 32 °C decreased to extinction within 3 days, whereas mean parasite abundance increased on hosts incubated at 18 and 24 °C. We show for the first time that gyrodactylid-infected fish have a preference for warmer waters and speculate that sick fish exploit the upper thermal tolerances of their parasites to self medicate

Unconventional ferromagnetic and spin-glass states of the reentrant spin glass Fe0.7Al0.3

Spin excitations of single crystal Fe0.7Al0.3 were investigated over a wide range in energy and reciprocal space with inelastic neutron scattering. In the ferromagnetic phase, propagating spin wave modes become paramagnon-like diffusive modes beyond a critical wave vector q0, indicating substantial disorder in the long-range ordered state. In the spin glass phase, spin dynamics is strongly q-dependent, suggesting remnant short-range spin correlations. Quantitative model for S(energy,q) in the ``ferromagnetic'' phase is determined.Comment: 4 pages, 5 figure

Windbreaks in North American Agricultural Systems

Windbreaks are a major component of successful agricultural systems throughout the world. The focus of this chapter is on temperate-zone, commercial, agricultural systems in North America, where windbreaks contribute to both producer profitability and environmental quality by increasing crop production while simultaneously reducing the level of off-farm inputs. They help control erosion and blowing snow, improve animal health and survival under winter conditions, reduce energy consumption of the farmstead unit, and enhance habitat diversity, providing refuges for predatory birds and insects. On a larger landscape scale windbreaks provide habitat for various types of wildlife and have the potential to contribute significant benefits to the carbon balance equation, easing the economic burdens associated with climate change. For a windbreak to function properly, it must be designed with the needs of the landowner in mind. The ability of a windbreak to meet a specific need is determined by its structure: both external structure, width, height, shape, and orientation as well as the internal structure; the amount and arrangement of the branches, leaves, and stems of the trees or shrubs in the windbreak. In response to windbreak structure, wind flow in the vicinity of a windbreak is altered and the microclimate in sheltered areas is changed; temperatures tend to be slightly higher and evaporation is reduced. These types of changes in microclimate can be utilized to enhance agricultural sustainability and profitability. While specific mechanisms of the shelter response remain unclear and are topics for further research, the two biggest challenges we face are: developing a better understanding of why producers are reluctant to adopt windbreak technology and defining the role of woody plants in the agricultural landscape

The Allometry of Host-Pathogen Interactions

Understanding the mechanisms that control rates of disease progression in humans and other species is an important area of research relevant to epidemiology and to translating studies in small laboratory animals to humans. Body size and metabolic rate influence a great number of biological rates and times. We hypothesize that body size and metabolic rate affect rates of pathogenesis, specifically the times between infection and first symptoms or death.We conducted a literature search to find estimates of the time from infection to first symptoms (t(S)) and to death (t(D)) for five pathogens infecting a variety of bird and mammal hosts. A broad sampling of diseases (1 bacterial, 1 prion, 3 viruses) indicates that pathogenesis is controlled by the scaling of host metabolism. We find that the time for symptoms to appear is a constant fraction of time to death in all but one disease. Our findings also predict that many population-level attributes of disease dynamics are likely to be expressed as dimensionless quantities that are independent of host body size.Our results show that much variability in host pathogenesis can be described by simple power functions consistent with the scaling of host metabolic rate. Assessing how disease progression is controlled by geometric relationships will be important for future research. To our knowledge this is the first study to report the allometric scaling of host/pathogen interactions

Tidal and groundwater fluxes to a shallow, microtidal estuary : constraining inputs through field observations and hydrodynamic modeling

This paper is not subject to U.S. copyright. The definitive version was published in Estuaries and Coasts 35 (2012): 1285-1298, doi:10.1007/s12237-012-9515-x.Increased nutrient loading to estuaries has led to eutrophication, degraded water quality, and ecological transformations. Quantifying nutrient loads in systems with significant groundwater input can be difficult due to the challenge of measuring groundwater fluxes. We quantified tidal and freshwater fluxes over an 8-week period at the entrance of West Falmouth Harbor, Massachusetts, a eutrophic, groundwater-fed estuary. Fluxes were estimated from velocity and salinity measurements and a total exchange flow (TEF) methodology. Intermittent cross-sectional measurements of velocity and salinity were used to convert point measurements to cross-sectionally averaged values over the entire deployment (index relationships). The estimated mean freshwater flux (0.19 m3/s) for the 8-week period was mainly due to groundwater input (0.21 m3/s) with contributions from precipitation to the estuary surface (0.026 m3/s) and removal by evaporation (0.048 m3/s). Spring–neap variations in freshwater export that appeared in shorter-term averages were mostly artifacts of the index relationships. Hydrodynamic modeling with steady groundwater input demonstrated that while the TEF methodology resolves the freshwater flux signal, calibration of the index– salinity relationships during spring tide conditions only was responsible for most of the spring–neap signal. The mean freshwater flux over the entire period estimated from the combination of the index-velocity, index–salinity, and TEF calculations were consistent with the model, suggesting that this methodology is a reliable way of estimating freshwater fluxes in the estuary over timescales greater than the spring– neap cycle. Combining this type of field campaign with hydrodynamic modeling provides guidance for estimating both magnitude of groundwater input and estuarine storage of freshwater and sets the stage for robust estimation of the nutrient load in groundwater.Funding was provided by the USGS Coastal and Marine Geology Program and by National Science Foundation Award #0420575 from the Biocomplexity/Coupled Biogeochemical Cycles Program

Gyrodactylus salinae n. sp. (Platyhelminthes: Monogenea) infecting the south European toothcarp Aphanius fasciatus (Valenciennes) (Teleostei, Cyprinodontidae) from a hypersaline environment in Italy

Background: Historically, non-native species of Gambusia (Poeciliidae) have been used to control larval stages of the Asian tiger mosquito, Stegomyia albopicta Reinert, Harbach et Kitching, 2004 throughout Italy. The potential utility of indigenous populations of Aphanius fasciatus (Valenciennes) (Teleostei: Cyprinodontidae) as an appropriate alternative biological control is currently being explored. A sub-sample of ten fish collected from Cervia Saline, Italy (salinity 65 ppt; 30°C) to assess their reproductive capability in captivity, harboured a moderate infection of Gyrodactylus von Nordmann, 1832 (Platyhelminthes, Monogenea). A subsequent morphological and molecular study identified this as being a new species. Results: Gyrodactylus salinae n. sp. is described from the skin, fins and gills of A. fasciatus. Light and scanning electron microscopical (SEM) examination of the opisthaptoral armature and their comparison with all other recorded species suggested morphological similarities to Gyrodactylus rugiensoides Huyse et Volckaert, 2002 from Pomatoschistus minutus (Pallas). Features of the ventral bar, however, permit its discrimination from G. rugiensoides. Sequencing of the nuclear ribosomal DNA internal transcribed spacers 1 and 2 and the 5.8S rRNA gene and a comparison with all species listed in GenBank confirmed they are unique and represent a new species (most similar to Gyrodactylus anguillae Ergens, 1960, 8.3% pair-wise distance based on 5.8S+ITS2). This represents the first species of Gyrodactylus to be described from Aphanius and, to date, has the longest ITS1 (774 bp) sequenced from any Gyrodactylus. Additional sampling of Cervia Saline throughout the year, found G. salinae n. sp. to persist in conditions ranging from 35 ppt and 5°C in December to 65 ppt and 30°C in July, while in captivity a low level of infection was present, even in freshwater conditions (0 ppt). Conclusions: The ability of G. salinae n. sp. to tolerate a wide range of salinities and temperatures shows its potential to readily adapt to several environmental conditions. These findings, together with the fact that A. fasciatus is a protected species and is considered as a biological control organism, necessitate further studies on the ecology and virulence of G. salinae n. sp

Attention-deficit/hyperactivity disorder (ADHD) symptoms and academic entrepreneurial preference: is there an association?

Although commercialization of research activities has drawn some research attention, more studies are warranted to clearly understand the drivers behind academic entrepreneurship. The present paper investigates the association between attention-deficit/hyperactivity disorder (ADHD) symptoms and academic entrepreneurial preference. ADHD symptoms have typically been associated with impaired occupational functioning among wage employees. Recent studies, however, indicate that the same symptoms of ADHD that are a liability for wage employees may work out differently for entrepreneurs. Building on previous studies that link ADHD symptoms to entrepreneurship, and using the theoretical lens of person-environment fit, we hypothesize that ADHD symptoms (at the so-called subclinical level) are associated with academic entrepreneurial preference. Results of our data from academic researchers in France, Spain, and Italy (N = 534) show that there is a negative association between attention-deficit symptoms and academic entrepreneurial preference. However, there is no link between hyperactivity symptoms and academic entrepreneurial preference