Fishing and the impact of marine reserves in a variable environment

We use discrete-time models to investigate the impact of marine reserve establishment on fishery catch and biomass levels in open-access and quota-regulated fisheries under conditions of recruitment variability and natural mortality events. We find that under the conditions of variability tested, reserves can increase the probability of achieving target levels of biomass (60%, 35%, and 5% of carrying capacity) and can reduce catch variability in neighbouring fisheries, making future planning in the fishery more efficient. The size of the reserve required to meet each objective will depend on the initial condition of the stock and the exploitation rate in the fishery. Reserve coverage of between 20% and 40% prevent stock collapse in most cases. In heavily exploited fisheries, reserves are also likely to enhance mean catches, particularly in highly variable systems. If the stock has previously been heavily exploited, large reserves (greater than or equal to60%) may be required to significantly increase the probability of achieving target biomass levels. However, once stocks have recovered, reserve coverage may be reduced without a reduction in this probability of success

The importance of habitat quality for marine reserve fishery linkages

We model marine reserve - fishery linkages to evaluate the potential contribution of habitat-quality improvements inside a marine reserve to fish productivity and fishery catches. Data from Mombasa Marine National Park, Kenya, and the adjacent fishery are used. Marine reserves increase total fish biomass directly by providing refuge from exploitation and indirectly by improving fish habitat in the reserve. As natural mortality of the fish stock decreases in response to habitat enhancement in the reserve, catches increase by up to 2.6 tonnes (t).km(-2).year(-1) and total fish biomass by up to 36 t.km(-2). However, if habitat-quality improvement reduces the propensity of fish to move out of the reserve, catches may fall by up to 0.9 t.km(-2).year(-1). Our results indicate that habitat protection in reserves can underpin fish productivity and, depending on its effects on fish movements, augment catches

Key behavioural and cognitive employee outcomes : a social exchange model

This paper serves to integrate social exchange with organisational justice and performance theory. Social exchange relationships are represented by employees&rsquo; perceptions of workplace inequity and evaluated using justice rules. Employees are expected to have in-role and extra-role behavioural responses and cognitive responses to inequity. It is theorised that behavioural and cognitive responses are moderated by the employee&rsquo;s perceptions of organisational justice. Much employee performance, commitment, engagement, retention and turnover may be explained by this comprehensive model.<br /

Gender differences in organizational justice predicting the key employee outcomes of organizational commitment, job satisfaction and turnover intention

All four types of organizational justice &ndash; distributive, procedural, interpersonal and informational &ndash; were included in this study of gender differences. Both male and female respondents perceived the distributive-procedural justice and interpersonal-informational justice pairings similarly and weakly. Females consistently discriminated more clearly across the pairings, however. The effect of the four justices was also found to be gender-dependent. Males&rsquo; perception of distributive justice directly predicted their turnover intentions and commitment to the organization, while females&rsquo; perception of distributive justice predicted only job satisfaction. Males&rsquo; perceptions of procedural and information justice both predicted job satisfaction. Females&rsquo; informational justice perceptions predicted job satisfaction and commitment to the organization. The paper contributes to the literature by presenting results from all four justice types and the simultaneous use of the three outcomes of job satisfaction, organizational commitment and intention to quit. Overall, the males had a diffuse set of relationships between the justice types and the outcomes, whereas the relationships between the justice types andthe outcomes for females tended more to follow a limited number of pathways. The study was validated with data collected on two separate occasions.<br /

Picosecond electrical spectroscopy using monolithic GaAs circuits

This article describes an experimental apparatus for free-space mm-wave transmission measurements (spectroscopy). GaAs nonlinear transmission lines and sampling circuits are used as picosecond pulse generators and detectors, with planar monolithic bowtie antennas with associated substrate lenses used as the radiating and receiving elements. The received pulse is 270 mV amplitude and 2.4 ps rise time. Through Fourier transformation of the received pulse, 30–250 GHz measurements are demonstrated with <=0.3 dB (rms) accuracy

Convergent interviewing : a qualitative diagnostic technique for researchers

Purpose &ndash; This paper aims to widen knowledge of and explore how convergent interviewing can be used to identify key issues within an organization.Design/methodology/approach &ndash; This paper introduces the convergent interviewing technique and describes the method of selecting the interview subjects. The construction of a round of interviews is explained. The content of the interviews is described and the particular probing nature of the questions demanded by the convergent interview process is explained. The ways to analyze the full set of interviews for groupings or categories is also described. The case study example of a broad research question about influences on work behaviors in a local government council is used to illustrate the convergent interviewing technique.Findings &ndash; The key issues revealed by using the technique can be subsequently used for a variety of research and consulting purposes and settings. Convergent interviewing is an effective research method, which conserves resources.Originality/value &ndash; Convergent interviewing enables researchers to determine the most important and/or key issues within a population rather than a full list of issues in an organization or barriers to change in a particular organizational context. <br /

Micro-Structured Ferromagnetic Tubes for Spin Wave Excitation

Micron scale ferromagnetic tubes placed on the ends of ferromagnetic CoTaZr spin waveguides are explored in order to enhance the excitation of Backward Volume Magnetostatic Spin Waves. The tubes produce a closed magnetic circuit about the signal line of the coplanar waveguide and are, at the same time, magnetically contiguous with the spin waveguide. This results in a 10 fold increase in spin wave amplitude. However, the tube geometry distorts the magnetic field near the spin waveguide and relatively high biasing magnetic fields are required to establish well defined spin waves. Only the lowest (uniform) spin wave mode is excited.Comment: 3 pages, 3 figure

Using organizational justice to predict in-role and extra-role performance works in different ways for men relative to women

Distributive, procedural, interpersonal and informational justices were included in this study of gender differences in in-role and extra-role behavior. Distributive justice predicted performance, organizational commitment and OCB for men but only performance and job satisfaction for women. Procedural justice predicted job satisfaction for men and did not predict any outcomes for women. Informational justice predicted job satisfaction for both male and female respondents. Informational justice predicted female but not male organizational commitment and in-role performance. Interpersonal justice predicted male but not female organizational citizenship behavior. The study demonstrates important distinctions between the four organizational justice types and how men and women respond differently to those distinctions. The differences in the drivers of in-role performance between men and women may also have practical implications for managers. For example, distributive justice was a direct in-role performance driver for both genders, but informational justice provides an incremental direct effect for women.<br /

A Multinational Analysis of Mutations and Heterogeneity in PZase, RpsA, and PanD Associated with Pyrazinamide Resistance in M/XDR Mycobacterium tuberculosis.

Pyrazinamide (PZA) is an important first-line drug in all existing and new tuberculosis (TB) treatment regimens. PZA-resistance in M. tuberculosis is increasing, especially among M/XDR cases. Noted issues with PZA Drug Susceptibility Testing (DST) have driven the search for alternative tests. This study provides a comprehensive assessment of PZA molecular diagnostics in M/XDR TB cases. A set of 296, mostly XDR, clinical M. tuberculosis isolates from four countries were subjected to DST for eight drugs, confirmatory Wayne's assay, and whole-genome sequencing. Three genes implicated in PZA resistance, pncA, rpsA, and panD were investigated. Assuming all non-synonymous mutations cause resistance, we report 90% sensitivity and 65% specificity for a pncA-based molecular test. The addition of rpsA and panD potentially provides 2% increase in sensitivity. Molecular heterogeneity in pncA was associated with resistance and should be evaluated as a diagnostic tool. Mutations near the N-terminus and C-terminus of PZase were associated with East-Asian and Euro-American lineages, respectively. Finally, Euro-American isolates are most likely to have a wild-type PZase and escape molecular detection. Overall, the 8-10% resistance without markers may point to alternative mechanisms of resistance. Confirmatory mutagenesis may improve the disconcertingly low specificity but reduce sensitivity since not all mutations may cause resistance