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Microwave and thermal problems in manufacturing high‐power microwave attenuators are considered and some proposals of thick film solutions are presented. Theoretical considerations have been confronted with the results of measurements.

The viable system model (VSM) provides a way to understand communication structures in an organization. It gives us a means to visualize and analyze information channels relating the functions in an enterprise, a corporation, or any other kind of organization. At the heart of the VSM is the application of Ashby's law of requisite variety. The resulting models help to analyze and discuss what variety attenuation of operations and what variety amplification of management can establish requisite variety. Many studies and applications show that the complexity management laws described by Ashby and Beer hold, and that managerial, operational and environmental varieties tend to equate. The amplifiers and attenuators, however, should be designed to do so with minimum damage to people and to cost. The purpose of this paper is to determine to what extent the design of amplifiers and attenuators is possible if these are realized based on linguistic communication, and whether this design can be automated in these cases.

The paper uses logical presentation of ideas along with examples from cases. The basic argument is that the design of information channels – amplifiers and attenuators – relies on self‐organizing processes that depend on an operation called linguistic predication.

The paper demonstrates that linguistic predication is not computable based on the model of the Turing machine so that this operation is restricted to be carried out by human agents. In these cases, technology is limited to providing a technical means for communication and social processes.

While there is a large knowledge base of literature in the field of applications of the VSM there is less work providing concepts and guidelines for designing information channels. This paper offers a conceptual and logical argument for their characteristics based on linguistics and philosophy of language.

The purpose of this study is the synthesis and characterization of a CMYK palette (cyan of Cr-BiVO₄, magenta of Pr-CeO₂, yellow of Bi-(Ce,Zr)O₂ composite and black of YMnO₃) as an eco-friendly polyfunctional palette that combines (a) high near-infrared reflectance (cool pigments) that allows moderate temperatures in indoor environments and the urban heat island effect; (b) photocatalytic activity for the degradation of organic contaminants of emerging concern of substrates in solution (such as Orange II or methylene blue) and gaseous (NO_x and volatile organic compounds such as acetaldehyde or toluene); (c) X-ray radiation attenuators associated with bismuth ions; and (d) biocidal effect combined with co-doping with bactericidal agents.

Pigments were prepared by a solid-state reaction and characterized by X-ray diffraction, diffuse reflectance spectroscopy, photocatalytic activity over Orange II and scanning electron microscopy.

The behaviour of the proposed palette was compared to that of a commercial inkjet palette, and an improvement in all functionalities was observed.

The functionalities of pigments allow the building envelope and indoor walls to exhibit temperature-moderating effects (with the additional effects of moderating global warming and increasing air conditioning efficiency), purification and disinfection of both indoor and outdoor air, and radiation attenuation.

The proposed palette and its polyfunctional characterization are novel.

The purpose of this paper is to provide a platform to improve leadership practices through variety engineering in terms of amplifying and attenuating variety.

Chemers's functional integration of image management, relation development and resource deployment as the building blocks of leadership is mapped onto Espejo et al.'s variety engineering individual‐task loop, consisting of cognitive, interactive and task venues.

It is found that traditional leadership can be usefully mapped onto the language of variety engineering.

Management is distinguished from leadership. The paper is an early attempt to translate a leadership model into the language of cybernetics.

Scholars have proposed that the negative effects of service failures can be countered by developing and maintaining high quality customer-company relationships or by providing excellent service recovery to customers. While both strategies have been proposed as ways to overcome the negative effects of service failures, there are only a limited number of studies that have examined their joint effects. The purpose of this paper is to fill this gap by investigating the impact of these two strategies jointly on rumination (brooding and reflection), anger and customer forgiveness (revenge, avoidance and benevolence).

The experimental design used in this study is an adaptation of Mattila’s (2001) research design, which manipulated both the level of service recovery and relationship. A total of 677 respondents were assigned randomly to one of the six experimental conditions. Multi-group structural equation modeling was employed to estimate the proposed model across three relational conditions.

This study suggests that the buffering effects are directly triggered by the impact of relationships, whereas, the magnifying effects are primarily related to the customer’s cognitive processes. This study reveals multiple forms of concurrent buffering and magnifying effects in service failures.

The findings of the study led to a classification system of the various forms of buffering and magnifying effects of relationships in the event of service failures. The four active roles of relationships are identified as damage control, benefit catalyst, benefit attenuator and damage catalyst. This proposed typology breaks new ground for theorizing about relationship utilization in negative incidents.

Parachute recovery systems are described from a systems perspective. Parachute recovery is particularly suited to tactical fixed wing UAV systems that require a high degree of mobility by allowing air vehicle recovery onto unprepared terrain. The descent environment is described, and the impact of wind on recovery is considered. The relative merits of cruciform, round and parafoil canopies are assessed, taking three real‐world systems as design examples. Throughout, design considerations are approached from a systems perspective, with a view to producing safe, autonomous and accurate recovery systems.

The purpose of the paper is concerned with one of the main contributions from the field of management cybernetics, the Viable System Model (VSM) developed by Beer (1972). This paper analyses what happens in terms of the VSM when a firm engages in production offshoring.

The paper is conceptual and develops four propositions about the nature of variety balance that production firms face, and what adjustments they make in the original viable system, both in terms of the properties of one or more of the basic subsystems and in the network of couplings between them.

The paper shows the production offshoring organisation as a dynamic adaptive system in search of ways to cope effectively with external forces that undermine its viability. The paper discusses how VSM can advance production offshoring research by both supplementing and linking established approaches such as transaction cost economics, the resource-based view and the eclectic theory of international production.

This research highlights the effects of geographical expansion of the firm’s operation on the stability of the firm itself. Using the VSM perspective, the paper provides opportunities to systematically track the changes that occur in the production offshoring firm and diagnose what they imply for the viability of the system as a whole.

TNT, the Australian‐based worldwide freight forwarding organisation has acquired a BAe 146QT freighter aircraft for operations within its European freight forwarding network.

The purpose of this paper is to assess the occurrence of the extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamase genes in 144 Escherichia coli isolates recovered from 160 vegetable salad samples.

Among the 144 E. coli isolates recovered from 160 vegetable salads, 17 (12 percent) ceftazidime-resistant isolates were screened for ESBL production with the double disk-diffusion test. The ESBL-producing isolates were characterized for antimicrobial resistance, the presence of virulence genes and plasmid-mediated quinolone resistance (PMQR) determinants. The isolates were also subjected to phylogenetic group typing. The existence of plasmid AmpC genes and mutations in the regulatory region of the chromosomal AmpC gene was assessed using polymerase chain reaction (PCR) and sequencing. All β-lactamase isolates were further characterized by pulsed-field gel electrophoresis to determine the genetic relatedness.

Overall, 17 (12 percent) of the 144 E. coli isolates studied were ceftazidime resistant. Among the 17 isolates, 13 (77 percent) were multidrug resistant and four (23.5 percent) were ESBL producers. The bla CTX-M14 was the only gene detected. Of the 12 AmpC-producing isolates, three (18 percent) harbored plasmid-encoded AmpC and sequencing analysis of the chromosomal AmpC genes revealed mutations in the promoter/attenuator region. PMQR determinants were detected in 9 (52 percent) isolates. A was the most prevalent phylogenetic group (56 percent), followed by groups B1 (31 percent), D (6 percent), and B2 (6 percent). PCR showed that six (50 percent) ESBL/AmpC-producing E. coli isolates carried one and/or two virulence genes. Pulsed-field gel electrophoresis showed no epidemiological relationship between these isolates.

This study places vegetable salads within the spectrum of ecological niches that may be vehicles for antibiotic-resistant bacteria/genes with clinical interest and these findings are worthy of attention as their spread to humans by ingestion cannot be dismissed.