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Fretting corrosion—a surface damage occurring between two closely fitting surfaces subject to slight vibrational movement—has caused trouble in machinery ever since the first closely fitting machined parts were put together. It is something different from ordinary wear or rusting of the usual chemical nature, and it is not always recognised as fretting corrosion by users of equipment in which it occurs. ‘Friction oxidation,’ ‘wear oxidation,’ ‘false brinelling,’ ‘chafing,’ ‘bleeding’ and ‘cocoa’ are some of the names that have been applied to the phenomenon. One of the results of work carried out by the Mechanical Engineering Research Laboratory of the D.S.I.R., briefly described in CORROSION TECHNOLOGY, May 1954, is that it is possible to correlate the degree of damage with such variables as total number of oscillations, load or atmospheric humidity. In the United States, too, much work has been done on fretting corrosion and ways of combating it. So that as many as possible could benefit from this research, the American Society for Testing Materials organised a Symposium in which leading experts gave their findings. The Symposium has recently been published as a booklet. Here are shortened versions of two of the papers presented.

The purpose of this paper is to study the effect of surface salt spray duration on the fretting wear and electrochemical corrosion behaviors of Inconel 690 alloy.

A high-temperature steam generator was applied to salt spray test samples, a fretting wear rig was used to realize the damage behavior tests, an electrochemical workstation was applied to analysis the changes of each sample’s corrosion dynamic response before and after fretting wear.

The thickness of the oxide film that formed on sample surface was increased with the salt spray duration, and somewhat it could act as lubrication during the fretting wear process; however, the corrosive chloride would accelerate the fretting mechanical damage behavior.

In a salt steam spray condition, the fretting tribo-corrosion behaviors of Inconel 690 alloy surface was studied.

This chapter describes five disciplinary domains of research or lenses that contribute to the design of a team tutor. We focus on four significant challenges in developing Intelligent Team Tutoring Systems (ITTSs), and explore how the five lenses can offer guidance for these challenges. The four challenges arise in the design of team member interactions, performance metrics and skill development, feedback, and tutor authoring. The five lenses or research domains that we apply to these four challenges are Tutor Engineering, Learning Sciences, Science of Teams, Data Analyst, and Human–Computer Interaction. This matrix of applications from each perspective offers a framework to guide designers in creating ITTSs.

The Iranian banking industry has been greatly affected by dramatic changes in macroeconomic conditions over the past several decades owing to volatile oil revenues, changing fiscal and monetary policies, and the imposition of US sanctions. The main objective of this paper is to estimate potential credit losses in the Iranian banking sector due to macroeconomic shocks and assess the minimum economic capital requirements under the baseline and distressed scenarios. The paper also contrasts the applications of linear and nonlinear models in estimating the impacts of macroeconomic shocks on financial institutions.

The paper uses a multistage approach to derive the portfolio loss distribution for banks. In the first step, the dynamic relationship between the selected macroeconomic variables are estimated using a VAR model to generate the stress scenarios. In the second step, the default probabilities are estimated using a quantile regression model and the results are compared with those of the conventional linear models. Finally, the default probabilities are simulated for a one-year time horizon using Monte-Carlo method and the portfolio loss distribution is calculated for hypothetical portfolios. The expected loss includes the loss given default for loans drawn randomly and uniformly distributed and exposed at default values when loans are assigned a fixed value.

The results indicate that the loss distributions under all scenarios are skewed to the right, with the linear model results being very similar to those of quantile at the 50% quantile, but very unlike those at the 10% and 90% quantiles. Specifically, the quantile model for the 90% (10%) quantile generates estimates of minimum economic capital requirement that are considerably higher (lower) than those using the linear model.

The study has focused on credit risk because of lack of data on other types of risk at individual bank level. The future studies can estimate the aggregate economic capital using a risk aggregation approach and a panel data (not presently available), which could further improve the accuracy of the estimates.

The fiscal and monetary authorities in developing countries, specially oil-exporting countries, can follow the risk assessment approach to assess the health of their banking system and adapt policies to mitigate the impacts of large macroeconomic shocks on their financial markets.

This is the first paper estimating the portfolio loss distribution for the Iranian banks under turbulent macroeconomic conditions using linear and nonlinear models. The case study can be applied to other developing and emerging countries, particularly those highly dependent on natural resources, prone to extreme macroeconomic shocks.

The purpose of this paper is to optimize a mixed juice made from Brazilian Cerrado fruits (cagaita, mangaba and marolo).

The juices were evaluated by rheological, physical, physicochemical, nutritional and sensory acceptance analyses. The mixture design is a widely used tool for product optimization, allowing the determination of factors, combinations and levels that provide best responses.

The results show that using mangaba pulp negatively contributed to juice acceptance, but resulted in the highest ascorbic acid content. The treatments produced using cagaita and marolo pulps presented a greater acceptance by consumers, and contributed to higher antioxidant activity and phenolic compounds content. The juice prepared with a mixture of equivalent quantities of the three fruits had the highest β-carotene and lycopene contents.

This research has shown that different fruit combinations can improve sensory and nutritional characteristics, adding value to the final product.

The processing of mixed juices could increase population access to the nutrients present in Brazilian Cerrado fruits, given that they are seasonal and perishable fruits.

In recent years, there has been an increase in the development of new food products based on Cerrado native fruits, however information on the chemical and nutritional characteristics, rheological behavior, and sensory attributes of the derivative products are still limited, resulting in a lack of scientific investments in this area. In addition, it is necessary to optimize the developed products to offer the consumer a unique product, combining the characteristics of two or more fruits, which adds value to the final product.

In 2019, a popular revolution toppled Sudan's long-term military president, Umar al-Bashir. The country then entered a three-year transition toward democratic rule during which power was shared between Sudan's military and civilian political organizations. In this period, international organizations and foreign governments were quick to proclaim their support for Sudan's democratic transition. However, policy reforms during Sudan's transition went beyond changes to formal political institutions, as the transitional government implemented major programs of economic restructuring. These restructurings were supported by Sudan's international partners, who normalized a discourse that Sudan was “overindebted,” and who held that political and economic reforms ought naturally to accompany each other. As a result, the transitional government implemented a shock program of liberalization and austerity that imposed material hardship on much of Sudanese society, including during a global recession resulting from the COVID-19 pandemic. This contributed to endangering the transition itself and the progressive promises of Sudan's 2019 revolution.

This chapter traces the history of how Sudan was excluded from Western financial and commercial markets through the imposition of sanctions in the 1990s. This caused Sudan to explore non-Western sources of external financing in East Asia and the Arabian Gulf. This history then shapes the contested ways in which Sudan's debts are counted by international institutions to create the misleading impression that the country is overindebted. Finally, the chapter examines how different elites coalesced to impose a program of shock fiscal austerity and economic liberalization during a crucial political moment, which helped to imperil the country's fragile political transition.

The native species from western Mato Grosso do Sul provide fruits with unique sensory characteristics and high nutrient concentrations. Tropical fruit consumption is increasing due to the growing recognition of the nutritional value. These fruits play important roles through the marketing of their products and nutritionally through their consumption. All fruits are edible and are used in the food industry and well sensory accepted. The purpose of this paper is to verify the physicochemical characteristics, bioactive compounds and antioxidant activity in fruits collected in the Cerrado and Pantanal biomes from western Mato Grosso do Sul.

The fruits of baru, bocaiuva, jatobá, jenipapo and pequi were collected. To characterize them, longitudinal diameter, transverse diameter, total soluble solids, acidity, pH, ascorbic acid, total phenolics, antioxidant capacity, total sugar, glucose and macro and micronutrient contents analysis were performed in triplicate.

Jatobá presented the highest values of vitamin C. For phenolics, baru and jatobá stood out; bocaiuva presented the highest results for sugars, while jatobá was superior for glucose. The fruits with the highest antioxidant capacity, DPPH, were pequi and baru, while via ABTS the jatobá was the highest. Baru presented higher levels of nitrogen, phosphorus, magnesium, copper, zinc and iron. The bocaiuva presented the highest results for potassium and sulfur, the jatobá calcium and manganese. Jenipapo stood out with its boron content. Magnesium presented superior results in the baru, jenipapo and bocaiuva. The results reinforce the diversity of physicochemical characteristics.

The increase of the flow of available information, together with the growth of multicultural influences, the search for wholesome diet and the diversity of flavors and colors make these fruits important regional development tools. Their characteristics encompass national and international exploration potential that arouse consumer interest and contribute to the pursuit of innovations. In addition, the native species mentioned above provide fruits with unique sensory characteristics. Their consumption is increasing in the markets due to the growing recognition of their nutritional value. Therefore, these fruits play important roles, economically, through the marketing of their products and nutritionally through their consumption.

This article reports on the contribution that complementary therapies can make to the well‐being of service users who are recovering from mental distress. As part of a wider strategy to promote awareness of a range of self‐management techniques at a forensic psychiatric hospital, complementary therapies (massage and aromatherapy) were provided. This article reports on a review of the evidence of the mental health benefits of the regular provision of these therapies. Further research is needed to establish the effectiveness of massage and aromatherapy for the forensic psychiatric population.