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A precise and rapid temperature cycling of a small volume of fluid is vital for an effective DNA replication process using the polymerase chain reaction (PCR). The purpose of this paper is to study the velocity and temperature fields inside a rotating PCR‐tube during cooling of the enclosed liquid.

The velocity and temperature fields inside a rotating PCR‐tube during cooling of the enclosed liquid are studied. By using computational fluid dynamics, the time development of the flow can be investigated in detail. Owing to the rotation, the flow exhibits features which could never arise in a non‐rotating system.

An intricate azimuthal boundary layer flow is presented and explained. The inherent problem of stratification of the temperature is discussed, and different methods towards a remedy are presented. By analyzing the governing equations, some properties of the flow observed in the simulations are explained. It is shown that increasing the rate of rotation does not improve temperature homogenization.

The simulations were performed for a limited number of temperature boundary conditions, as well as a specific simulation geometry.

The analytical and simulation results offer fundamental insight into the physics behind increased DNA duplication. Further simulations offer possible design improvements.

While many studies have probed the effects of buoyancy in rotating cylinders and the development of boundary layers in stratified flows in conical containers rotating around their axis of symmetry, little work has been specifically focused on the case where the axis of rotation is normal to the direction of the stratification, which is the case in the present study.

The purpose of this study is to develop a framework of strategies to achieving customer order flexibility in and related to the order-to-delivery (OTD) process. The purpose is also to investigate how companies prioritize various strategies to achieve customer order flexibility.

Based on a literature review, pre-tests and conceptual reasoning, a conceptual framework of strategies related to the order-to-delivery process was developed. The strategies were linked to the order quantity and delivery lead-time flexibility dimensions. This structure resulted in six groups covering enabling as well as remedial strategies. An empirical interview study of ten customer–supplier relationships was conducted.

The interviews identified additional strategies, thereby expanding the framework. The enabling strategies with the highest median values were “have continuous contact with the customer's purchaser” and “use safety stock of raw materials/semi-finished products”. The remedial strategy with the highest median was “re-plan/re-prioritize the order backlog”. In the delivery sub-process, it was more common to apply remedial strategies for delivery lead-time than for order quantities.

The developed framework is a contribution to the literature on operational flexibility in and related to the OTD process. It complements existing knowledge by taking a supplier perspective.

Suppliers can use the framework as a tool to understand and systematically achieve better customer order flexibility in and related to the OTD process. Customers can use the framework as a checklist for supplier evaluation and supplier development.

Few identified studies include empirical data on customer order flexibility.

Switches and crossings (S&Cs) are an important component of Banverket's (the Swedish National Rail Administration's) infrastructure and are associated with 13 per cent of the total maintenance cost. Therefore, it is important that a detailed study of different aspects of the costs of S&Cs should be undertaken to analyze individual maintenance costs. This will in the future give the possibility of enhancing the management of infrastructure.

A case study is undertaken to study, identify and classify the costs of S&Cs for Banverket. Data are taken from Banverket's maintenance information systems and accounting system.

A rough estimation of the cost for individual S&Cs can be identified in this way. The cost varies very much and a more detailed study is needed to validate the cost on this level. The average cost of a group of S&Cs varies less and is therefore more likely to reflect the true cost. The cost varies depending on the amount and type of traffic. Moreover, the type of S&C seems to reflect the cost variation, but further investigation is needed to verify this conclusion.

The accounting system does not store data for individual assets, and further research would be more fruitful if individual costs could be recorded by the entrepreneur. Larger repairs should be separated from annual maintenance tasks in a future study. Data from this study could be used to build a life cycle cost model for S&Cs.

Cost identification is a first step in finding a way to organize maintenance in a more cost‐effective way.

The paper shows a way to distribute costs (in the accounting system) down to individual subsystems of the infrastructure. This enables analysts to find cost drivers and plan for modification of or reinvestment in the asset.

THE Reference Department of Paisley Central Library today occupies the room which was the original Public Library built in 1870 and opened to the public in April 1871. Since that date two extensions to the building have taken place. The first, in 1882, provided a separate room for both Reference and Lending libraries; the second, opened in 1938, provided a new Children's Department. Together with the original cost of the building, these extensions were entirely financed by Sir Peter Coats, James Coats of Auchendrane and Daniel Coats respectively. The people of Paisley indeed owe much to this one family, whose generosity was great. They not only provided the capital required but continued to donate many useful and often extremely valuable works of reference over the many years that followed. In 1975 Paisley Library was incorporated in the new Renfrew District library service.

The purpose of this paper is to conduct a structured review of literature on lesson study (LS) in initial teacher education (ITE). The focus was on how learning and observation were discussed in studies of LS in ITE.

Each national team (in Norway and Britain) undertook independent searches of published peer-reviewed articles. The resulting articles were then combined, screened and collaboratively reviewed, the focus being on two areas of enquiry: how learning is represented and discussed; and the extent to which observation is described and used to capture evidence of learning.

The literature review indicated that there was no universally held understanding of, or explanation for, the process of observation, how it should be conducted, and who or what should be the principal focus of attention. There was also a lack of clarity in the definition of learning and the use of learning theory to support these observations.

This study was limited to a review of a selection of peer-reviewed journal articles, published in English. It arrives at some tentative conclusions, but its scope could have been broadened to include more articles and other types of published material, e.g. theses and book chapters.

Research that investigates the use of LS in ITE needs to be more explicit about how learning is defined and observed. Furthermore, LS research papers need to assure greater clarity and transparency about how observations are conducted in their studies.

This literature review suggests that discussion of both learning and observation in ITE LS research papers should be strengthened. The review highlights three principal challenges that ITE LS researchers should consider: how to prepare student-teachers to observe (professional noticing being a promising option), the wide variation in the focus of classroom observation in ITE lesson studies, and discussion of what is understood by learning needs to stand at the heart of preparation for lesson studies in ITE.

The purpose of this study is to explore the impact of sustainability (environmental, social and governance or ESG) practices on the financial performance (FP) of the Nordic financial industry.

The study covers a sample selection of observations for a total of 152 firm-years for 39 financial companies within the Nordic region (Sweden, Denmark, Finland and Norway) for the business years including 2015–2019. Data regarding ESG and FP indicators were extracted from the Thomson Reuters Eikon database in July 2020. This is a quantitative study using regression and a generalized method of moments.

Using static and dynamic estimators, the authors found both positive and negative impacts of sustainability practice on FP. The authors identified a negative relationship between ESG practices and FP (return on invested capital, return on equity and earnings per share). The authors identified a positive relationship between governance and return on assets.

A key contribution to the accounting literature is the finding that there is a risk for financial firms in adopting sustainability practices, as they follow a logic that contradicts the purely economic rationale. On the other hand, the positive relationship between governance and FP helps not only companies but also regulators and researchers to understand the positive impact of a good governance structure.

Recently, reverse logistics (RL) has become more prominent due to growing environmental concerns, social responsibility, competitive advantage and high efficiency by customers because of the expansion of product selection and shorter product life cycle. However, effective implementation of RL results in some direct advantages, the most important of which is winning customer satisfaction that is vital to a firm’s success. Therefore, paying attention to customer feedback in supply chain and logistics processes has recently increased so that manufacturers have decided to transform their RL into customer-centric RL. Hence, this paper aims to identify the features of a mobile phone which affect consumer purchasing behaviour and to analyse the interrelationship among them to develop a framework for customer-centric RL. These features are studied based on website analysis of several mobile phone manufacturers. The special focus of this paper is on social media data (Twitter) in an attempt to help the decision-making process in RL through a big data analysis approach.

A portfolio of mobile phone features that affect consumer’s mobile phone purchasing decisions has been taken from website analysis by several mobile phone manufacturers to achieve this objective. Then, interrelationships between the identified features have been established by using big data supplemented with interpretive structural modelling (ISM). Apart from that, cross-impact matrix multiplication, applied to classification analysis, was carried out to graphically represent these features based on their driving power and dependence.

During the study, it has been observed from the ISM that the chip (F5) is the most significant feature that affects customer’s buying behaviour; therefore, mobile phone manufacturers realize that this is to be addressed first.

The focus of this paper is on social media data (Twitter) so that experts can understand the interaction between mobile phone features that affect consumer’s decisions on mobile phone purchasing by using the results.

Recently, reverse logistics (RL) has become more prominent due to growing environmental concerns, social responsibility, competitive advantages and high efficiency by customers because of expansion of product selection and shorter product life cycle. However, effective implementation of RL results in some direct advantages, the most important of which is winning customer satisfaction that is vital to a firm's success. Therefore, paying attention to customer feedback in supply chain (SC) and logistics processes has recently increased, so manufacturers have decided to transform their RL into customer-centric RL. Hence, this paper aims to identify the features of a mobile phone which affect consumers’ purchasing behavior and to analyze the causality and prominence relations among them that can help decision-makers, policy planners and managers of organizations to develop a framework for customer-centric RL. These features are studied based on analysis of product review sites. This paper's special focus is on social media (SM) data (Twitter) in an attempt to help the decision-making process in RL through a big data analysis approach.

This paper deals with identifying mobile phone features that affect consumer's mobile phone purchasing decisions. Using the DEMATEL approach and using experts' insights, a cause and effect relationship diagram was generated through which the effect of features was analyzed.

Eighteen features were categorized in terms of cause and effect, and the interrelationships of features were also analyzed. The threshold value is calculated as 0.023, and the values lower than that were eliminated to obtain the digraph. F6 (camera), F13 (price) and F5 (chip) are the most prominent features based on their prominent score. It was also found that the F5 (chip) has the highest driving power (1.228) and acts as a causal feature to influence other features.

The focus of this article is on SM data (Twitter), so that experts can understand the interaction between mobile phone features that affect consumer's decision on mobile phone purchasing by using the results. This study investigates the degree of influence of features on each other and categorizes the features into cause and effect groups. This study is also intended to help organizational decision-makers move toward a reverse customer SC.

This study investigates the spillover effects between exchange rate changes and stock returns in China. The authors find that no significant interconnections exist between stock returns and exchange rates changes.

Although the conventional structural VAR (SVAR) approach fails to examine the contemporaneous effects, the Markov switching SVAR model captures the volatile structure of the Chinese financial market. The regime-switching estimates indicate that volatile structure tends to be significant during two financial crisis periods.

Notwithstanding the fact that exchange rate changes cannot Granger-cause stock returns in the long run, its contemporaneous spillover effects on stock returns are found to be statistically significant.

This study aims to shed light on the spillover effects between exchange rate changes and stock returns in China, as the Chinese currency is becoming flexible and China’s stock market has undertaken important reforms. The spillovers between the two markets are of topical importance due to the increasing connections between China and the global economy.

The purpose of this paper is to explore differences in the degree of innovation in employment relations (ER) between emerging and established firms,

A large national telephone survey (N=1,416) of both emerging (<5 years) and established firms was conducted.

Emerging firms were more casualised, less unionised, and experiencing higher levels of market expansion and unpredictability. Despite these differences, younger firms showed otherwise remarkable similarity to older firms across a range of ER practices, and both categories showed a reliance on business networks, rather formal training, for ER knowledge. While introducing ER changes more rapidly than older (and larger) firms, they were converging towards a suite of ER practices similar to that adopted by older firms. The results suggest that, if anything, established firms may have been engaged in greater innovation in more unusual ER practices.

Only managers were surveyed. The data are cross-sectional rather than longitudinal. As the study was undertaken in only one country, replication in other settings would be desirable.

The results raise major doubts about the notion that new firms represent the cutting edge of innovation, and highlights the degree to which newer firms match or mimic older firms’ ER architecture.