The economic cost of weeds in dryland cotton production systems of Australia

Economic losses and costs associated with weeds in dryland cotton production are important, both for growers and for industry bodies when making decisions about research priorities and research and development funding. A survey was conducted to provide information on weed types, control strategies and estimated costs to growers. We used information from the survey to estimate conventional financial losses due to weeds, and as a basis for evaluating aggregate economic (society) impacts. An economic surplus model was used to estimate the aggregate societal impact of weeds for three production regions in north-eastern Australia. The annual economic costs associated with weeds were estimated to be $41 million, and the on-farm financial costs were$25 million. While these are past (sunk) costs, and based on a total removal of weeds, the approach outlined here can be used to begin evaluating likely future returns from technologies or management improvements for different agricultural problems.Weeds, Dryland Cotton, and Economics, Crop Production/Industries, Environmental Economics and Policy,

Union representation, collective voice and job quality: an analysis of a survey of union members in the UK finance sector

This article seeks to identify whether employee perceptions of job quality are better in instances where an onsite union representative is present. It also seeks to identify whether the relationship between onsite representative presence and job quality is explained by employee perceptions of union collective voice. The analysis, based on a survey of union members in the UK finance sector, demonstrates that employee perceptions of several dimensions of job quality are better where an onsite representative is present, and that this can be explained by the higher perceptions of union collective voice that onsite representatives engender

Simplified fuzzy control for flux-weakening speed control of IPMSM drive

This paper presents a simplified fuzzy logic-based speed control scheme of an interior permanent magnet synchronous motor (IPMSM) above the base speed using a flux-weakening method. In this work, nonlinear expressions of d-axis and q-axis currents of the IPMSM have been derived and subsequently incorporated in the control algorithm for the practical purpose in order to implement fuzzy-based flux-weakening strategy to operate the motor above the base speed. The fundamentals of fuzzy logic algorithms as related to motor control applications are also illustrated. A simplified fuzzy speed controller (FLC) for the IPMSM drive has been designed and incorporated in the drive system to maintain high performance standards. The efficacy of the proposed simplified FLC-based IPMSM drive is verified by simulation at various dynamic operating conditions. The simplified FLC is found to be robust and efficient. Laboratory test results of proportional integral (PI) controller-based IPMSM drive have been compared with the simulated results of fuzzy controller-based flux-weakening IPMSM drive system

Patients’ and clinicians’ perspectives on the clinical utility of the Rheumatoid Arthritis Foot Disease Activity Index

Although patient-reported outcome measures (PROMs) are recommended in clinical practice, their application in routine care is limited. The Rheumatoid Arthritis Foot Disease Activity Index (RADAI-F5) is a validated PROM for assessing foot disease in rheumatoid arthritis (RA). To explore patient and clinician opinions and perceptions of the clinical utility of the Rheumatoid Arthritis Foot Disease Activity Index (RADAI-F5), eight RA patients and eight clinicians routinely involved in the management of RA patients participated in one semi-structured remote video-based interview. They provided their perspectives on the barriers and facilitators to clinical implementation of the RADAI-F5. Three global themes were identified; 'Feet are a priority' as the impact of RA on the feet negatively impacted upon patient quality of life. The second theme was 'Need for a clinically feasible foot PROM' as participants recognised the current lack of a clinically feasible tool to determine RA foot disease. The third global theme of ‘Implementation’ was drawn together to form two subordinate themes: ‘Facilitators to RADAI-F5 implementation’ as the tool can promote communication, guide management, help screen foot symptoms, monitor foot disease status and treatments, and promote patient education and; ‘Barriers to RADAI-F5 implementation’ as there were associated practical difficulties, including lack of appointment time, administrative burdens, IT barriers and preference for further RADAI-F5 validation using imaging. The RADAI-F5 has significant potential as a clinical tool to aid foot disease management. However, implementation challenges must be overcome before broad adoption in rheumatology clinics. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00296-022-05147-8

Anisotropic nonlinear elasticity in a spherical bead pack: influence of the fabric anisotropy

Stress-strain measurements and ultrasound propagation experiments in glass bead packs have been simultaneously conducted to characterize the stress-induced anisotropy under uniaxial loading. These measurements, realized respectively with finite and incremental deformations of the granular assembly, are analyzed within the framework of the effective medium theory based on the Hertz-Mindlin contact theory. Our work shows that both compressional and shear wave velocities and consequently the incremental elastic moduli agree fairly well with the effective medium model by Johnson et al. [J. Appl. Mech. 65, 380 (1998)], but the anisotropic stress ratio resulting from finite deformation does not at all. As indicated by numerical simulations, the discrepancy may arise from the fact that the model doesn't properly allow the grains to relax from the affine motion approximation. Here we find that the interaction nature at the grain contact could also play a crucial role for the relevant prediction by the model; indeed, such discrepancy can be significantly reduced if the frictional resistance between grains is removed. Another main experimental finding is the influence of the inherent anisotropy of granular packs, realized by different protocols of the sample preparation. Our results reveal that compressional waves are more sensitive to the stress-induced anisotropy, whereas the shear waves are more sensitive to the fabric anisotropy, not being accounted in analytical effective medium models.Comment: 9 pages, 8 figure

Quorum Regulated Resistance of Vibrio cholerae against Environmental Bacteriophages.

Predation by bacteriophages can significantly influence the population structure of bacterial communities. Vibrio cholerae the causative agent of cholera epidemics interacts with numerous phages in the aquatic ecosystem, and in the intestine of cholera patients. Seasonal epidemics of cholera reportedly collapse due to predation of the pathogen by phages. However, it is not clear how sufficient number of the bacteria survive to seed the environment in the subsequent epidemic season. We found that bacterial cell density-dependent gene expression termed "quorum sensing" which is regulated by signal molecules called autoinducers (AIs) can protect V. cholerae against predatory phages. V. cholerae mutant strains carrying inactivated AI synthase genes were significantly more susceptible to multiple phages compared to the parent bacteria. Likewise when mixed cultures of phage and bacteria were supplemented with exogenous autoinducers CAI-1 or AI-2 produced by recombinant strains carrying cloned AI synthase genes, increased survival of V. cholerae and a decrease in phage titer was observed. Mutational analyses suggested that the observed effects of autoinducers are mediated in part through the quorum sensing-dependent production of haemaglutinin protease, and partly through downregulation of phage receptors. These results have implication in developing strategies for phage mediated control of cholera

PCaAnalyser: A 2D-Image Analysis Based Module for Effective Determination of Prostate Cancer Progression in 3D Culture

Three-dimensional (3D) in vitro cell based assays for Prostate Cancer (PCa) research are rapidly becoming the preferred alternative to that of conventional 2D monolayer cultures. 3D assays more precisely mimic the microenvironment found in vivo, and thus are ideally suited to evaluate compounds and their suitability for progression in the drug discovery pipeline. To achieve the desired high throughput needed for most screening programs, automated quantification of 3D cultures is required. Towards this end, this paper reports on the development of a prototype analysis module for an automated high-content-analysis (HCA) system, which allows for accurate and fast investigation of in vitro 3D cell culture models for PCa. The Java based program, which we have named PCaAnalyser, uses novel algorithms that allow accurate and rapid quantitation of protein expression in 3D cell culture. As currently configured, the PCaAnalyser can quantify a range of biological parameters including: nuclei-count, nuclei-spheroid membership prediction, various function based classification of peripheral and non-peripheral areas to measure expression of biomarkers and protein constituents known to be associated with PCa progression, as well as defining segregate cellular-objects effectively for a range of signal-to-noise ratios. In addition, PCaAnalyser architecture is highly flexible, operating as a single independent analysis, as well as in batch mode; essential for High-Throughput-Screening (HTS). Utilising the PCaAnalyser, accurate and rapid analysis in an automated high throughput manner is provided, and reproducible analysis of the distribution and intensity of well-established markers associated with PCa progression in a range of metastatic PCa cell-lines (DU145 and PC3) in a 3D model demonstrated

GNSS Differential Code Bias Determination Using Rao‐Blackwellized Particle Filtering

The Assimilative Canadian High Arctic Ionospheric Model (A-CHAIM) is a near-real-time data assimilation model of the high latitude ionosphere, incorporating measurements from many instruments, including slant Total Electron Content measurements from ground-based Global Navigation Satellite System (GNSS) receivers. These measurements have receiver-specific Differential Code Biases (DCB) which must be resolved to produce an absolute measurement, which are resolved simultaneously with the ionospheric state using Rao-Blackwellized particle filtering. These DCBs are compared to published values and to DCBs determined using eight different Global Ionospheric Maps (GIM), which show small but consistent systematic differences. The potential cause of these systematic biases is investigated using multiple experimental A-CHAIM test runs, including the effect of plasmaspheric electron content. By running tests using the GIM-derived DCBs, it is shown that using A-CHAIM DCBs produces the lowest overall error, and that using GIM DCBs causes an overestimation of the topside electron density which can exceed 100% when compared to in situ measurements from DMSP

Investor sentiment and firm capital structure

We provide novel evidence of the role of investor sentiment in determining firms' capital structure decisions from three perspectives: leverage ratio, debt maturity and leverage target adjustment. We find that when investor sentiment is high, firms increase their leverage ratios, supporting our contention that high investor sentiment increases firms' debt capacity and facilitates the use of an aggressive leverage policy. Debt maturity is shorter in high sentiment periods, implying that firms are confident about future earnings and use shorter debt maturity to signal their financial solvency. Leverage target adjustment is slower in low sentiment periods, indicating higher costs of external finance. Furthermore, the sentiment-leverage relationship sensitivity is greater for financially constrained firms. Our extended analysis determines that leverage-increasing firms generate lower stock returns subsequent to a period of high sentiment, offering practical insights into the economic consequences of increasing leverage in high sentiment periods on corporate value for investors. Our research advances the understanding of the impact of investor sentiment on firms' financing decisions and stock returns