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The direct comparison of similar polymers was achieved by a technique of differential GPC which, according to Runyon provided a simple yet sensitive technique that was relatively insensitive to operational variables. In this procedure the ‘standard’ polymer was dissolved in THF or an alternative suitable solvent, and the solution was used as the eluent in the GPC.

The trend towards higher density, higher frequency, higher power active devices in placing increasingly difficult demands on device packaging. Materials with high thermal conductivities are replacing the traditional ceramics in hermetic, high power packages, and MCM/ hybrid modules. Thermally enhanced plastic packages more frequently feature heat sinks embedded in the package for direct attachment of the power devices. Today's challenge in electronic packaging is to dissipate the heat from the source, the device itself, without affecting its electrical performance or reliability. The material directly contacting the device is the die attach medium. On lower power packages, the die bond line is not usually the highest thermal resistance in the thermal path. With highly conductive substrates and heat sinks, the die attach material now becomes the critical element directly in series with the highly conductive substrate. Fundamental limitations in thermal properties of about 3 W/mK exist in present‐day organic adhesives, primarily of the thermosetting type. This thermal conductivity (k) does not meet the current demands of thermally enhanced plastic laminate packages, MCMs, or direct die attach to heat spreaders or heat sinks. This paper describes the development, properties and application of electrically conductive thermoplastic adhesive pastes having thermal conductivity values as high as 35 W/mK, and able to produce thin, void‐free bond lines for maximum thermal transfer. The key material variables are isolated and evaluated for their impact of the k value. DOEs (design of experiments) were run to optimise the combination of the key variables, namely size/shape of the filler and the volume fraction to produce the highest k without sacrificing other functional properties such as adhesion. The effect of polymer chemistry (thermoset and thermoplastic) was also studied. The properties of the newly developed, enhanced conductivity thermoplastic adhesives are compared with other material technologies and examples of current applications reviewed.

Studies addressing rural residents’ understanding of global warming and their willingness to pay higher prices to mitigate it are very limited. The purpose of this study is to examine the general understanding and attitudes of rural residents in China regarding global warming and their willingness to pay higher prices to mitigate it.

This study surveyed 1,185 rural residents in three counties of coastal, middle and western China. Multivariate regression analysis was conducted to reveal the relationships between the willingness to pay higher prices to mitigate global warming and influencing factors.

The majority of respondents had heard of global warming; however, their knowledge of the phenomenon and its causes was very limited. Most respondents admitted the likelihood of risks from global warming. Although most respondents thought they had an obligation to mitigate global warming, only a small percentage of them were willing to pay higher prices to address the problem; the unwillingness of respondents to pay higher prices to mitigate global warming may have been associated with their low income and perceived inability to handle the cost, externalisation of responsibility and causes and lack of knowledge of how to affect it.

This study examines the general understanding and attitudes of rural residents in China regarding global warming and their willingness to pay higher prices to mitigate it. The research is conducive to climate change communications and the implementation of climate policies in China’s rural areas.

Autism spectrum disorder is a kind of neurodevelopmental disorder characterized by persistent deficits in social communication and interaction across multiple contexts, and restricted, repetitive patterns of behavior, interests or activities. The purpose of this paper is to determine the effectiveness of sensory integration intervention on emotional-behavioral problems in children with autism spectrum disorder.

This research was conducted in a pretest-posttest design with control group. The participants were 30 children with autism spectrum disorder (6–11 years old) who were selected through convenience sampling from among children with autism spectrum disorder in Zeinab center of Isfahan and were randomly divided into two groups of 15 subjects. The children of the experimental group received 14 sessions of sensory integration intervention while the control group did not receive this intervention. To measure emotional-behavioral problems, the Behavior Assessment System for Children-Second Edition was used. To analyze the data, ANCOVA and MANCOVA tests were used.

The results showed that sensory integration intervention improves emotional-behavioral problems and its subscales (hyperactivity, aggression, behavioral problems, anxiety, depression, somatization, attention problems, learning difficulties, atypicality and withdrawal) in children with autism spectrum disorder.

Therefore, it can be concluded that sensory integration intervention can be a suitable treatment for reducing sensory problems and improving emotional-behavioral problems in children with autism spectrum disorder.

The study of the effect of sensory integration on emotional-behavioral problems in children with autism spectrum disorder is necessary as a simple and non-side-effect educational and therapeutic method, both as a step to fill the research gap in this field, besides being a cheap and affordable way for improving the various skills of children with autism spectrum disorder for professionals, teachers, parents and educators.

The purpose of this paper is to characterize and understand the effects of polymer binder, thixotropic agent, solvent and organic medium content on the rheological properties of silver pastes for screen printing front electrode films of solar cells.

Dispersions of silver particles (surface modified with oleic acid) in ethyl cellulose (EC) polymer solutions with and without thixotropic agent were prepared, and yield stress values were measured by setting shear stress to characterize the inter-particle interaction strength of pastes. Steady-state flow, three interval thixotropy shear test and oscillatory measurements were conducted to study the effect of EC polymer and thixotropic agent on viscosity, structure rebuilding and viscoelastic properties of electrode pastes. The effect of solvent was studied by investigating the steady viscosity of cellulose acetate butyrate (CAB) polymer solutions and Ag dispersions.

Weak flocculation network of silver particles was produced because of depletion flocculation. Besides the interaction between thixotropic agent micelles, EC polymer also has a significant interaction with thixotropic agent. Merely increasing EC polymer or thixotropic agent content is not the best way to prevent the layer printed from laying down. The effect of solvent on the viscosity of paste is mainly attributed to the difference of hydromechanics radius and configuration of CAB polymer in solvents. With the increase of organic medium content, the properties of electrode pastes were converted from rigidity to flexibility.

It is still a challenge to obtain high-quality front electrode films for crystalline silicon solar cells by screen printing, because of the difficulty in reducing shadowing losses while ensuring a low series resistance and high filling factor. The paste rheological properties are the key properties related to the paste’s passing ability through the meshes and resistance of paste spreading on the substrate. Organic medium as an important component of the paste is acknowledged to be used to tailor the paste’s rheological properties and have a great role in screen printing.

Even more than 50 years after the Civil Rights Act of 1964 prohibited discrimination toward a number of groups in employment settings in the United States, workplace discrimination remains a persistent problem in organizations. This chapter provides a comprehensive review and analysis of contemporary theory and evidence on the nature, causes, and consequences of discrimination before synthesizing potential methods for its reduction. We note the strengths and weaknesses of this scholarship and highlight meaningful future directions. In so doing, we hope to both inform and inspire organizational and scholarly efforts to understand and eliminate workplace discrimination.

The present contribution is in the field of quantum modelling of macroscopic phenomena. The focus is on one enigmatic aspect of quantum physics, namely, the Einstein–Podolsky–Rosen paradox and entanglement. After a review of the state-of-the-art concerning macroscopic quantum effects and quantum interaction, this paper aims to propose a link between embryology and acupuncture in the framework of macroscopic intricate states induced by quantum mechanics.

The author uses the fractaquantum hypothesis which supposes that the quantum framework is applicable to all insecable elements in nature, whatever their size.

This contribution considers an open question related to a possible link between acupuncture and embryology: can a weak form of intrication be maintained during stem cell division to interpret the acupuncture meridians as an explicit manifestation of a macroscopic intricate system? The macroscopic structure suggested by quantum mechanics could be a beginning of explanation of acupuncture through the embryologic development.

A fundamental hypothesis is the fact that during cell division, cells keep some weak intrication.

This contribution suggests a structure of the acupuncture meridians. The links between the acupuncture points have to be searched in the embryologic development of the individual through a weak remaing intrication of some of his cells and not in present explicit relations.

A new link between occidental and oriental cultures is explored.

This contribution suggests conceptual links between acupuncture, embryology and macroscopic intricate states.

Purpose: Risk is a multifaceted concept, and its identification requires complex approaches that are often misunderstood. The consequence is that decisions are based on limited perception rather than the full value and meaning of what risk is, as a result, the way it is being tackled is incorrect. The individuals are often limited in their perceptions and ideas and do not embrace the full multifaceted nature of risk. Regulators and individuals want to follow norms and checklists or overuse models, simulations, and templates, thereby reducing responsibility for decision-making. At the same time, the wider use of technology and rules reduces the critical thinking of individuals. We advance the automation process by building robots that follow protocols and forget about the part of risk assessment that cannot be programed. Therefore, with this study, the objective of this study was to discover how people define risk, the influencing factors of risk perception and how they behave toward this perception. The authors also determine how the perception differed with age, gender, marital status, education level and region. The novelty of the research is related to individual risk perception during COVID-19, as this is a new and unknown phenomenon. Methodology: The research is based on the analysis of the self-administered purposely designed questionnaires we distributed across different social media platforms between February and June 2020 in Europe and in some cases was carried out as a interview over communication platforms such as “Skype,” “Zoom” and “Microsoft Teams.” The questionnaire was divided into four parts: Section 1 was designed to collect demographic information from the participants; Section 2 included risk definition statements obtained from literature and a preliminary discussion with peers; Section 3 included risk behavior statements; and Section 4 included statements on risk perception experiences. A five-point Likert Scale was provided, and participants were required to answer along a scale of “1” for “Strongly Agree” to “5” for “Strongly Disagree.” Participants also had the option to elaborate further and provide additional comments in an open-ended box provided at the end of the section. 466 valid responses were received. Thematic analysis was carried out to analyze the interviews and the open-ended questions, while the questionnaire responses were analyzed using various quantitative methods on IBM SPSS (version 23). Findings: The results of the analysis indicate that individuals evaluate the risk before making a decision and view risk as both a loss and opportunity. The study identifies nine factors influencing risk perception. Nevertheless, it must be emphasized that we can continue to develop models and rules, but as long as the risk is not understood, we will never achieve anything.