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An Autodesk Ember three-dimensional (3D) printer was used to print optical components from Clear PR48 photocurable resin. The cured PR48 was characterized by the per cent of light transmitted and the index of refraction, which was measured with a prism spectrometer. Lenses and diffraction gratings were also printed and characterized. The focal length of the printed lenses agreed with predictions based on the thin lens equation. The periodicity and effective slit width of the printed gratings were determined from both optical micrographs and fits to the Fraunhofer diffraction equation. This study aims to demonstrate the advantages offered by a layer-by-layer DLP printing process for the manufacture of optical components for use in the visible region of the electromagnetic spectrum.

A 3D printer was used to print both lenses and diffraction gratings from Standard Clear PR48 photocurable resin. The manufacturing process of the lenses and the diffraction gratings differ mainly in the printing angle with respect to the printer x-y-axes. The transmission diffraction gratings studied here were manufactured with nominal periodicities of 10, 25 and 50 µm. The aim of this study was to optically determine the effective values for the distance between slits, d, and the effective width of the slits, w, and to compare these values with the printed layer thickness.

The normalized diffraction patterns measured in this experiment for the printed gratings with layer thickness of 10, 25 and 50 µm are shown by the solid dots in Figures 8(a)-(c). Also shown as a red solid line are the fits to the experimental diffraction data. The effective values of d and w obtained from fitting the data are compared to the nominal layer thickness of the printed gratings. The effective distance between slits required to fit the diffraction patterns are well approximated by the printed layer thickness to within 14, 4 and 16 per cent for gratings with a nominal 10, 25 and 50 µm layer thickness, respectively.

Chromatic aberration is present in all polymer lenses, and the authors have not attempted to characterize it in this study. These materials could be used for achromatic lenses if paired with a crown-type material in an achromatic doublet configuration, because this would correct the chromatic aberration issues. It is worthwhile to compare the per cent transmission in cured PR48 resin (approximately 80 per cent) to the percent transmission found in common optical materials like BK7 (approximately 92 per cent) over the visible region. The authors attribute the lower transmission in PR48 to a combination of surface scattering and increased absorption. At the present time, the authors do not know what fraction of the lower transmission is related to the surface quality resulting from sample polishing.

There are inherent limitations to the 3D manufacturing process that affect the performance of lenses. Approximations to a curved surface in the design software, the printing resolution of the Autodesk Ember printer and the anisotropy due to printing in layers are believed to be the main issues. The performance of the lenses is also affected by internal imperfections in the printed material, in particular the presence of bubbles and the inclusion of debris like dust or fibers suspended in air. In addition, the absorption of wavelengths in the blue/ultraviolet produces an undesirable yellowing in any printed part.

One of the most interesting results from this study was the manufacture of diffraction gratings using 3D printing. An analysis of the diffraction pattern produced by these printed gratings yielded estimates for the slit periodicity and effective slit width. These gratings are unique because the effective slit width fills the entire volume of the printed part. This aspect makes it possible to integrate two or more optical devices in a single printed part. For example, a lens combined with a diffraction grating now becomes possible.

Emotional and interpretive responses to three short stories were noted in two study populations of similar age: Qatari students in a post-highschool foundation program preparing to attend branch campuses of western universities located in Qatar, and American students, many of Mexican-American heritage, from a small college in a rural setting in South Texas. It has long been thought that reading literature from a foreign culture confers educational value on the reader; in this investigation the nature of that ‘value’ was placed under study. Written responses to quiz questions or assignments were used as data; responses critical of or affirming of character, setting, plot, and literary tropes were particularly noted. Our data show that readings from an author whose culture was similar to the reader’s created interest and urged both intellectual and affective types of understanding, such as remembering, grieving, healing, forgiving, and feeling pride. Readings from ‘classic’ literature presented in historical context strongly enabled critical discussion among students in a multicultural setting, since the author’s absence from the scene ‘allows’ free conversation about his or her work without fear of insulting the author’s culture. Readings by contemporary writers from outside the reader’s culture, or ‘multicultural literature’, may cause some readers to shy away from the challenge of understanding another culture or to voice stereotypes instead of seeking ideas. Readings from outsider cultures, however, and the affective distancing of ‘othering’, enable the well-prepared educator and student to discuss how culture patterns our lives.

This paper aims to use the advertisements of three major brands – Chymol, Formamint and Lifebuoy Soap – to examine how advertisers responded to the 1918–1919 influenza pandemic in Great Britain influenza pandemic. It looks particularly at the ways in which marketing strategies changed and how these strategies were enacted in the lexical and semiotic choices (e.g. language, image, colour, typography, texture, materiality, composition and layout) of advertisements.

A total of 120 advertisements for the three brands were collected from the British Newspaper Archive and analysed using the theory and analytical tools of multimodal critical discourse analysis. The general themes and semiotic structures of the advertisements were identified, with the aim of deconstructing the meaning potentials of verbal and visual resources used to convey ideas about the pandemic, and how they work to shape public understanding of the products and make them appear as effective and credible.

Each brand rapidly changed their marketing strategy in response to the influenza pandemic, using such techniques as testimonials, hyperbole, scaremongering and pseudoscientific claims to persuade consumers that their products offered protection. Whilst these strategies may appear manipulative, they also had the function of fostering reassurance and sympathy amongst the general public in a moment of turmoil, indicating the important role of brands in building consumer trust and promoting a sense of authority in early twentieth-century Britain.

Exploring the way in which advertisers responded to the 1918‐1919 influenza pandemic reminds us of the challenges of distinguishing legitimate and illegitimate medical advice in a fast-moving pandemic and highlights the need to cast a critical eye to the public health information, particularly when it comes from unofficial sources with vested interests.

This paper aims to shed light on how children's literature in Africa deserves to be studied because African writers “decolonize” the minds of African children and children and adults around the world.

This paper defines children's literature from an African perspective and the “decolonization of the mind.” This is done to examine how two African writers provide narratives for children inspired by their cultures. They deal with themes, characters and symbols that interest children and adults.

Achebe and Youssef crossed many borders: the world of children and adults, animals and humans, vice and virtue, supernatural and real. Their stories take the reader on journeys that involve enriching, engaging and inspiring adventures.

Youssef and Achebe are prolific writers. Providing a survey of what is available in Arabic and Nigerian literature for children, is beyond the scope of this paper.

This paper sends a message to those in charge of the curriculum in schools in Egypt, the Arab countries, Africa and the world at large: decolonize the syllabi in schools because the world is not black and white. Literature for children that encourages critical thinking is available by African writers in Egypt, Nigeria and elsewhere.

The works discussed show that African writers are creative, and their works inspire the African child with pride in his/her identity, culture and heritage.

To the best of the author’s knowledge, no one has compared Egyptian and Nigerian literature for children before. Youssef and Achebe provide evidence that “Good literature gives the child a place in the world … and the world a place in the child.” – Astrid Lindgren.

The purpose of this investigation is to gain insight into parents' perceptions of benefits vs burdens (value) of educational and healthcare service received for their child with ASD. Parents are the main integrators of long-term educational and healthcare service for their child with ASD.

Design/methodology/approach included (1) a sentiment analysis of discussion forum posts from an autism message board using a rule-based sentiment analysis tool that is specifically attuned to sentiments expressed in social media and (2) a qualitative content analysis of one-on-one interviews with parents of children diagnosed with ASD, complemented with interviews with experienced educators and clinicians.

Findings reveal the link between customized service integration and long-term benefits. Both parents and service providers emphasize the need to integrate healthcare and educational service to create holistic long-term care for a child with ASD. Parents highlight the benefits of varied services, but availability or cost are burdens if the service is not publicly provided, or covered by insurance. Service providers' lack of experience with ASD and people's ignorance of the challenges of ASD are burdens.

Ensuring health outcomes for a child with ASD requires an integrated service system and long-term, customer-centric service process because the scope of service covers the child's entire childhood. Customized educational and healthcare service must be allocated and budgeted early in order to reach the goal of a satisfactory service output for each child.

This is the first service research to focus on parents' challenges with obtaining services for their child with ASD. This paper provides service researchers and managers insight into parents' perceptions of educational and healthcare service value (i.e. benefits vs. burdens) received for their child with ASD. These insights into customer-centric perceptions of value may be useful to research and may help service providers to innovate and provide integrated service directly to parents, or indirectly to service providers, who serve children with ASD.

This study investigates the existence of the environmental Kuznets curve (EKC) for deforestation for Ghana over the 1962–2018 the time period.

The study employs a time-varying approach, the bootstrap rolling window Granger causality test to achieve its set objectives.

The results from our study reveals an inverted “N” shape EKC for deforestation, implying that deforestation will initially decrease with increases in economic growth up to a certain income threshold and increases with further increases in economic growth beyond this income threshold up to a higher income threshold and then decrease with further increases in economic beyond the higher income threshold.

The results from the study project show that over time economic growth can serve as a natural panacea to cure and mitigate the ills of deforestation that have plagued Ghana's forests over the years.

The results further highlight the important role of strong institutions in fighting the deforestation menace.

The originality of this study lies in its methodology which allows for feedback from deforestation to the economy. This is in contrast to earlier studies on the EKC for deforestation which allowed causality only from deforestation to the economy.

The article introduces selected theoretical approaches to time and temporality relevant to the field of library and information science, and it briefly introduces the papers gathered in this special issue. A number of issues that could potentially be followed in future research are presented.

The authors review a selection of theoretical and empirical approaches to the study of time that originate in or are of particular relevance to library and information science. Four main themes are identified: (1) information as object in temporal perspectives; (2) time and information as tools of power and control; (3) time in society; and (4) experiencing and practicing time.

The paper advocates a thorough engagement with how time and temporality shape notions of information more broadly. This includes, for example, paying attention to how various dimensions of the late-modern time regime of acceleration feed into the ways in which information is operationalised, how information work is commodified, and how hierarchies of information are established; paying attention to the changing temporal dynamics that networked information systems imply for our understanding of documents or of memory institutions; or how external events such as social and natural crises quickly alter modes, speed, and forms of data production and use, in areas as diverse as information practices, policy, management, representation, and organisation, amongst others.

By foregrounding temporal perspectives in library and information science, the authors advocate dialogue with important perspectives on time that come from other fields. Rather than just including such perspectives in library and information science, however, the authors find that the focus on information and documents that the library and information science field contributes has great potential to advance the understanding of how notions and experiences of time shape late-modern societies and individuals.

The primary purpose of this study is to determine if the main character is a shapeshifter and, if so, how does the tale contribute to shapeshifting lore.

The focus of the study is confined to a version of the tale that appears in Jane Yolen's Folktales From Around the World (1986) and on summaries of other versions of shapeshifting tales when needed. Support for the findings is provided by an examination of the observations and rhetorical techniques employed by what appears to be an unreliable narrator and selected knowledge and practices from a variety of academic disciplines.

The research findings neither confirm nor deny that the main character is or is not a shapeshifter.

Instead, the critical reading confirms the traditional characterization of folktales as coming from diverse folk roots and disappearing or changing as they circulate through geographical space and narrative time.

It also implies that the tale has outgrown its practical and social folk roots and now extends far beyond that of traditional shapeshifting or literary folktales.

By bringing to light the racial and gender fears, ignorance and emotional and physical violence that lurk just below the surface of the society from which serpent-woman emerges, the study creates a haunting vision of the embedded biases that lurk just below the surface of many societies.

To this author's knowledge, this is the first study of this tale to appear in publication. The findings need further investigation.

This study aims to examine the way in which elderly people, men and women, with a terminal illness use language to construct a narrative about their “living-with-dying” experience.

This investigation is a secondary analysis based on a corpus of health and illness narratives collected by the Health Experiences Research Group at the University of Oxford and published by the DIPEx charity (available at: http://healthtalk.org/home).

This study shows that there are qualitative differences in the way in which not only elderly people but also men and women report their experience with terminal illness and their relation to death.

Understanding the different perspectives from which elderly people narrate their experiences of how they live while dying from terminal illness can help health professionals to develop more effective all-inclusive health policies and practices in end-of-life care.