Scaling properties of velocity and temperature spectra above the surface friction layer in a convective atmospheric boundary layer

International audienceWe report velocity and temperature spectra measured at nine levels from 1.42 meters up to 25.7 m over a smooth playa in Western Utah. Data are from highly convective conditions when the magnitude of the Obukhov length (our proxy for the depth of the surface friction layer) was less than 2 m. Our results are somewhat similar to the results reported from the Minnesota experiment of Kaimal et al. (1976), but show significant differences in detail. Our velocity spectra show no evidence of buoyant production of kinetic energy at at the scale of the thermal structures. We interpret our velocity spectra to be the result of outer eddies interacting with the ground, not "local free convection". We observe that velocity spectra represent the spectral distribution of the kinetic energy of the turbulence, so we use energy scales based on total turbulence energy in the convective boundary layer (CBL) to collapse our spectra. For the horizontal velocity spectra this scale is (zi ?o)2/3, where zi is inversion height and ?o is the dissipation rate in the bulk CBL. This scale functionally replaces the Deardorff convective velocity scale. Vertical motions are blocked by the ground, so the outer eddies most effective in creating vertical motions come from the inertial subrange of the outer turbulence. We deduce that the appropriate scale for the peak region of the vertical velocity spectra is (z ?o)2/3 where z is height above ground. Deviations from perfect spectral collapse under these scalings at large and small wavenumbers are explained in terms of the energy transport and the eddy structures of the flow. We find that the peaks of the temperature spectra collapse when wavenumbers are scaled using (z1/2 zi1/2). That is, the lengths of the thermal structures depend on both the lengths of the transporting eddies, ~9z, and the progressive aggregation of the plumes with height into the larger-scale structures of the CBL. This aggregation depends, in top-down fashion, on zi. The whole system is therefore highly organized, with even the smallest structures conforming to the overall requirements of the whole flow

Mixed genotype hepatitis C infections and implications for treatment

No abstract available

Student perceptions of workplace communications during co-operative workterm experiences

Co-operative education gives students the opportunity to observe important interpersonal skills while applying their technical knowledge. Eighty students on their second and third co-op work terms described communication incidents in face-toface,mobile text, and mobile voice situations perceived to have shaped relationships with their managers. Richness is provided by a qualitative analysis that asks students to express their feelings about how they are talked to by their supervisors. Results identify some apparent themes with respect to the use of message content and tone, media selection and message timing. They also show that students appear to value face-to-face communication and reveal that social extra-role relationships are important to student feelings of selfefficacy and attributions of manager effectiveness. These connections may form the basis for student development of their own communication styles. The results lead to suggestions of how to make the learning of communication skills more tangible within co-op programs

Using the I-MARKOR scale to identify market-oriented individuals in the financial services sector

Purpose – Extant studies of the market orientation of service firms rarely consider the contribution of individual employees to the realization of this orientation. Existing scales that measure market orientation reveal the perceptions of a key informant about the dominant orientation within the firm. These scales do not measure the willingness of employees to act in a market-oriented way. This paper aims to report the development of a multi-dimensional scale of individual market-oriented behavior. Design/methodology/approach – The scale development process included identification of items from focus groups with employees of a major Canadian financial services firm and the market orientation literature. A pretest with marketing practitioners and academics helped to purify and reduce the number of items. Finally, a sample of North American financial services employees responded to the items in a web-based questionnaire. Findings – Confirmatory factor analysis of the responses confirmed the presence of a single latent construct with three dimensions: information acquisition, information sharing and strategic response, measured by 20 items. Research limitations/implications – Although scale validation included both qualitative and quantitative tests that triangulated the opinions of multiple stakeholders in the service delivery chain, future research must also test the predictive validity of this scale. Practical implications – Such research is important to increase understanding of how service organizations foster market orientation. The I-MARKOR augments the organizational scorecard approach with individual level measurement. Originality/value – The scale provides a method to assess differences between individuals within an organization, enabling empirical research on differences between departments, roles, training and other characteristics that may influence the extent to which an individual performs market-oriented behaviors

Individual-level antecedents to market-oriented actions

Although often assessed at an organizational level, a market-oriented culture is supported by the attitudes and actions of the organization\u27s employees. A firm cannot develop a market orientation strategy without each employee\u27s active understanding, willingness, and ability to perform in a market-oriented fashion. Therefore, individual employees must experience a responsibility to gather and assess the value of market information, and a willingness to share it with other employees. We surveyed a cross-section of employees at many levels and roles in different North American financial services organizations. This research identified important individual-level antecedents that organizations must account for when attempting to stimulate company-wide market-oriented behaviors. These include the fostering of high-quality and matched psychological contracts, modeling of learning strategies by agile learners, and increased opportunities and time to develop personal ties between customers and employees in diverse roles within the firm

Internal stakeholder views of a market orientation strategy: Implications for implementation

The market orientation literature focuses upon external stakeholders as the content or target of a market orientation strategy. This is problematic for understanding the successful implementation of a market orientation strategy because internal stakeholders provide the link between strategy‐makers and external stakeholder targets. Anchored in market orientation, dynamic capabilities, and stakeholder research, the study describes how internal stakeholders in a market orientation process can impede or encourage the achievement of market‐oriented objectives by a market‐oriented company. Focus groups were conducted with both management and non‐management employees of a large market‐oriented financial services organisation that recently introduced a market‐oriented agency call program. The extent to which the company is market‐oriented was determined through preliminary interviews with senior executives and distributor/customers. Results highlight: (1) program antecedents related to employee disposition and control; (2) potentially competing program objectives (relationship and knowledge acquisition); (3) issues of role conflict, time constraints; and (4) the need to confirm program value through feedback solicited from other stakeholders

Prevalence of mixed genotype hepatitis C virus infections in the UK as determined by genotype‐specific PCR and deep sequencing

The incidence of mixed genotype hepatitis C virus infections in the UK is largely unknown. As the efficacy of direct acting antivirals is variable across different genotypes, treatment regimens are tailored to the infecting genotype, which may pose issues for the treatment of underlying genotypes within undiagnosed mixed genotype HCV infections. There is therefore a need to accurately diagnose mixed genotype infections prior to treatment. PCR-based diagnostic tools were developed to screen for the occurrence of mixed genotype infections caused by the most common UK genotypes, 1a and 3, in a cohort of 506 individuals diagnosed with either of these genotypes. The overall prevalence rate of mixed infection was 3.8% however this rate was unevenly distributed, with 6.7% of individuals diagnosed with genotype 3 harbouring genotype 1a strains and only 0.8% of samples from genotype 1a patients harbouring genotype 3 (p<0.05). Mixed infection samples consisted of a major and a minor genotype, with the latter constituting less than 21% of the total viral load and, in 67% of cases, less than 1% of the viral load. Analysis of a subset of the cohort by Illumina PCR-next generation sequencing resulted in a much greater incidence rate than obtained by PCR. This may have occurred due to the non-quantitative nature of the technique and despite the designation of false positive thresholds based on negative controls

Sofic-Dyck shifts

We define the class of sofic-Dyck shifts which extends the class of Markov-Dyck shifts introduced by Inoue, Krieger and Matsumoto. Sofic-Dyck shifts are shifts of sequences whose finite factors form unambiguous context-free languages. We show that they correspond exactly to the class of shifts of sequences whose sets of factors are visibly pushdown languages. We give an expression of the zeta function of a sofic-Dyck shift

Postrelease survival, vertical and horizontal movements, and thermal habitats of five species of pelagic sharks in the central Pacific Ocean

From 2001 to 2006, 71 pop-up satellite archival tags (PSATs) were deployed on five species of pelagic shark (blue shark [Prionace glauca]; shortfin mako [Isurus oxyrinchus]; silky shark [Carcharhinus falciformis]; oceanic whitetip shark [C. longimanus]; and bigeye thresher [Alopias superciliosus]) in the central Pacific Ocean to determine species-specific movement patterns and survival rates after release from longline fishing gear. Only a single postrelease mortality could be unequivocally documented: a male blue shark which succumbed seven days after release. Meta-analysis of published reports and the current study (n=78 reporting PSATs) indicated that the summary effect of postrelease mortality for blue sharks was 15% (95% CI, 8.5–25.1%) and suggested that catch-and-release in longline fisheries can be a viable management tool to protect parental biomass in shark populations. Pelagic sharks displayed species-specific depth and temperature ranges, although with significant individual temporal and spatial variability in vertical movement patterns, which were also punctuated by stochastic events (e.g., El Niño-Southern Oscillation). Pelagic species can be separated into three broad groups based on daytime temperature preferences by using the unweighted pair-group method with arithmetic averaging clustering on a Kolmogorov-Smirnov Dmax distance matrix: 1) epipelagic species (silky and oceanic whitetip sharks), which spent >95% of their time at temperatures within 2°C of sea surface temperature; 2) mesopelagic-I species (blue sharks and shortfin makos, which spent 95% of their time at temperatures from 9.7° to 26.9°C and from 9.4° to 25.0°C, respectively; and 3) mesopelagic-II species (bigeye threshers), which spent 95% of their time at temperatures from 6.7° to 21.2°C. Distinct thermal niche partitioning based on body size and latitude was also evident within epipelagic species