bluuebunny/crossref_metadata_2025 huggingface dataset:
Peculiarities of the prevalence of partial secondary adentia and its complications in children and adolescents
Authors: Doroshenko S. I. , Savonik S. M.
Published: February 2021

Rationale. The high prevalence of anomalies, partial adentia and its complications determine the importance of searching new optimal means of prevention, orthodontic and orthopaedic treatment, taking into account the age peculiarities of a child’s body during its formation.Objective: To study the prevalence, etiological factors and features of the clinical progression of partial secondary adentia and its complications in children and adolescents in order to develop optimal means of prevention, orthodontic and orthopaedic treatment.Materials and methods. 2276 people aged from 4 to 17 years were examined during the temporary, mixed and permanent dentition periods, in order to study the prevalence of partial secondary adentia and its complications in children and adolescents. The examinations were conducted in the organized child care of Kyiv (kindergartens, schools) and at the Department of Orthopedic Dentistry and Orthodontics of the private higher educational institution "KyivMedicalUniversity". All patients were divided into 3 age groups depending on the period of formation of the dento-maxillaire system.Results. According to the results of the examinations, the high prevalence of partial secondary adentia was detected in both posterior and anterior dentition, in particular, among the examined 2276 children, partial secondary adentia was detected in 359 people, including 115 children with the defect of the anterior area and 264 people had the defect of posterior dentition.The causes of partial secondary adentia in the examined children were: the removal of temporary and permanent teeth caused by caries and its complications - 278 (77.4%) cases, the second place takes – the loss of teeth caused by traumatic injuries - 34 children (9.3%).Deformity of dental arches was diagnosed in 278 people (77,43%) among the children with partial secondary adentia, indicating the high prevalence of such a pathology due to untimely dental care, in particular, the lack of prosthetic treatment.Conclusions. The occurrence of partial secondary adentia in children and adolescents caused by caries and its complications, as well as traumatic injuries in 77.4% of cases in the absence of prosthetic treatment leads to complications in the form of deformities of dental arches. Carrying out temporary teeth maintenance procedure until the term of their physiological change, as well as taking timely treatment, prevention and prosthetic measures will aid the harmonious development of a child’s dento-maxillaire system and prevention of complications.
Hemostasis – compendium for students
Authors: Kosmalska Martyna , Znajewska-Szulc Karolina , Bronowski Adrain
Published: February 2021

Hemostasis is one of many well-known systems that ensure a constant conditions of the organism's internal environment. This process is usually divided into two main stages: coagulation and fibrinolysis. Both of them occur simultaneously and under physiological conditions they are in dynamic equilibrium. There are primary and secondary hemostasis. The primary hemostasis leads to the formation a platelet clot that forms almost directly after a blood vessel has been ruptured. In the other hand, the secondary hemostasis is the activation of coagulation, which leads to the strengthening of the platelet plug through the fibrin network formation as a result of the polymerization of the soluble plasma protein fibrinogen. The key role in hemostasis plays the interaction of platelets – which are the smallest non nucleated blood cells that are formed from the cytoplasm of megakaryocytes, and plasma coagulation factors with vascular endothelial cells and subendothelial tissues. In this report it is decribed the process of physiological hemostasis, especially the newer concept of blood coagulation.
Morphofunctional state of the lungs respiratory part in normotensive and hypertensive rats after combined exposure to intermittent hypoxia and melatonin
Authors: Yanko Roman , Levashov Mikhail , Chaka Elena , Safonov Sergey
Published: February 2021

Aim. The purpose of this work was to study and compare the combined effect of intermittent normobaric hypoxia (INH) and melatonin on the morphological and biochemical indices of the lungs respiratory part in Wistar and spontaneous hypertensive rats (SHR). Material and methods. The studies were conducted on 48 young male rats Wistar and SHR lines. The experimental rats were daily exposed to hypoxic gas mixture (12 % oxygen in nitrogen) in intermittent mode: 15 min deoxygenation / 15 min reoxygenation for 2 hours. Animals also received oral melatonin at a dose of 5 mg /1 kg of body weight once daily.Results. The sizes of alveolus were reduced, but their number and placement density were increased in SHR rats after a combined effect of INH and melatonin. The results showed a significant decrease of the interalveolar septum thickness and a tendency to decrease of the hydroxyproline concentration in the lung tissue of the experimental rats, regardless of their line.Conclusions. The 28-day combined effect of INH and melatonin increase the total alveolar surface area and reduce the amount of connective tissue in the lungs of experimental rats. These changes can improve the efficiency of the intrapulmonary gas exchange processes.
Turning Toward the Sun
Authors: McArthur-Blair Joan , Cockell Jeanie
Published: February 2021

The power of hope doesn’t have just one method or one path. It is created in relation to the world around us. In the dark of the northern hemisphere’s winter months where we, the editors of this issue, live it is easy to see only darkness. And yet, there is light and hope. The Covid-19 vaccine is being delivered in many parts of the world, offering the dream that we might hug our friends and family before 2021 is over.
The Deterrent Effect of Ride-Sharing on Sexual Assault and Investigation of Situational Contingencies
Authors: Park Jiyong , Pang Min-Seok , Kim Junetae , Lee Byungtae
Published: February 2021

Research Spotlight
Dynamic Programming Deconstructed: Transformations of the Bellman Equation and Computational Efficiency
Authors: Ma Qingyin , Stachurski John
Published: February 2021

Transforming Dynamic Optimization Problems for Enhanced Computational Efficiency
Corporate Investment Relationships and the Search for Innovations: An Examination of Startups’ Search Shift Toward Incumbents
Authors: Polidoro Francisco , Yang Wei
Published: February 2021

Existing literature shows that corporate investment relationships play an important role in the development of startups. Although startups are relevant sources of innovations, especially those that radically depart from existing technologies, they often have limited access to resources. Corporate investment relationships are relevant to startups because they help them access resources of their corporate partners, especially those that are necessary for innovations to eventually achieve commercial success. This study examines the possibility that these relationships might also affect how startups search for innovations, producing greater alignment with the technologies of incumbents. Investigating this possibility is important because it can partly offset startups’ distinctiveness in technological domains of search and accordingly undercut learning opportunities available to incumbents. We argue that, following the formation of a corporate investment relationship, considerations related to capabilities and incentives result in a startup shifting the search for innovations toward technological domains of its corporate partner. We also argue that the radicalness of a startup’s innovations and the corporate partner’s commercial success exacerbate this search shift. We test these propositions in the context of biotech startups. Our difference-in-differences analysis shows that startups forming corporate investment relationships increase search in the domains of their corporate partners relative to analogous change observed among matching counterfactual startups without such relationships. We discuss implications for understanding of the influences of interorganizational relationships on startups’ technological trajectories and on incumbents’ learning and adaptation.
Using Analytical Hierarchy Process Methods in Cash Holding and Corporate Working Capital Management: an Asian Perspective
Authors: Jarrett Jeffrey Edward , Pan Xia , Du Wenjun
Published: February 2021

Cash holding behavior is an important financial behavior of the company, which reflects the company's financial strategy and management strategy. What are the factors that affect corporate cash holdings? How does the change in these factors affect the change in corporate cash holdings? Starting from two aspects of national macroeconomic environmental factors and microeconomic environmental factors, this paper tries to analyze these factors and how they affect corporate cash holdings. Working Capital Management is an important part of the company's financial management, which is closely related to the value creation of the company. What is the content of working capital management? How to manage the working capital effectively? This paper expounds the contents of working capital management from the perspective of process management, and expounds how to effectively manage working capital from the perspective of situational management. To link these two areas ids the goal of this study.
The Impediments and Evolution of Derivatives in Sub Sahara Africa
Authors: Chidaushe Wilbert Kudakwashe
Published: February 2021

The research follows on the Arusha declaration of 2005 and the global financial crisis of 2008 and explored the impediments and the evolution of derivatives in Sub Sahara Africa with special attention onZimbabwe, Botswana and South Africa. The research has been based on a review of literature of the seminal authors and through a conduct of questionnaire surveys in each of the three countries of Zimbabwe, Botswana and South Africa. The purpose of the study was to identify any disparities in the evolution of commodities and financial derivatives in the Sub-Saharan African countries. The study uncovered that registered banks in Botswana and Zimbabwe relied so much on the forward agreement to protect against financial risk. Credit default swaps (CDS), currency options and simple foreign exchange swaps also were relatively used in Botswana by most commercial banks to hedge against risk. In South Africa, a wide variety of simple and complex futures and options products are effectively applied on commodities and currencies to protect against financial losses. Rodrigues, Schwarz and Seeger (2012) noted that the initiation of formal derivative markets can accelerate growth in the economies and decrease the fluctuations of the Gross Domestic Product.
Conflitos territoriais como espaço de disputas entre memória e história: Análise de processos judiciais da Itaipu Binacional contra os Guarani no Oeste do Paraná
Authors: Brighenti Clovis Antonio , De Oliveira Osmarina
Published: February 2021

No presente artigo analisamos os percursos e fundamentos das disputas em torno da história e memória entre o Estado e seus entes (Itaipu, Poder Judiciário) contra o povo Guarani, do subgrupo linguístico “Ava”, na região Oeste do estado do Paraná. Através da análise de algumas Ações Judiciais envolvendo a disputa por terra, constatamos um discurso construído em torno de elementos que confluem para desconsiderar a história Guarani e desconstruir a memória da ocupação territorial regional. Na disputa por memória, materializada na questão territorial, está a hidrelétrica Itaipu Binacional contra a população Guarani. Nos últimos anos os Guarani intensificaram processos de ações por conquistas territoriais, questionado a “memória oficial” sobre a região e evidenciaram elementos que desnudam a história construída em torno do vazio demográfico e de sua suposta integração à sociedade. Eles passaram a ocupar os últimos fragmentos de Mata Atlântica fora do Parque Nacional do Iguaçu, localizados na Área de Preservação Permanente (APP) do lago de Itaipu. Buscaremos demonstrar que a propriedade da terra não é o principal elemento em disputa, mas sim a memória que pode tornar-se ameaçadora para a imagem da empresa mais lucrativa no Sul do Brasil, construída numa época de exceção de direitos.
“A doçura que envolve”: a culinária brasileira do Nordeste em Baú de Ossos
Authors: Gabriel Maria Alice Ribeiro
Published: February 2021

A obra do médico e memorialista brasileiro Pedro da Silva Nava (1903-1984) oferece uma série de alusões à alimentação. Em Baú de Ossos (1972), primeiro volume das Memórias, inúmeras definições relativas à aparência, cores, sabores, componentes alimentares, ingredientes e texturas são apresentados e avaliados. Considerando o valor histórico de tais referências, este artigo pretende expor menções de Pedro Nava à cozinha regional, relativas à Região Nordeste, no século XIX e princípios do século XX. Este estudo desenvolve uma análise histórico-comparativa para examinar os temas relativos à alimentação e à culinária que emergem de episódios biográficos sobre a família Nava. A análise indica como Pedro Nava descreveu aspectos culturais e sociais de pratos populares e tradicionais do Nordeste brasileiro.
A administração dos bens confiscados dos Jesuítas na capitania de São Paulo, 1760-1782
Authors: Rocha Ilana Peliciari
Published: February 2021

A Companhia de Jesus destacou-se durante o período colonial com uma atuação não apenas no campo espiritual, mas também nas esferas político-econômicas. Acumulou poder local e um patrimônio significativo resultado da habilidade administrativa, de doações de particulares e da Coroa. Não há um inventário suficiente desse conjunto patrimonial, mas seguramente era um dos maiores para a época. Com as reformas pombalinas, os jesuítas acabaram por serem expulsos e seus bens confiscados pela Coroa portuguesa. Faziam parte do patrimônio jesuítico imóveis, escravizados e gado, entre outros, além da administração de aldeamentos, e distribuíam-se por toda a colônia. Com o confisco, o direcionamento desses bens foi variado; alguns foram utilizados pela administração colonial; outros resultaram em receita, por venda e arrendamento, à exceção dos que continuaram com a Igreja por meio de outras ordens religiosas. Esse direcionamento variado e o encaminhamento administrativo com relação a esses bens resultaram numa confusão administrativa e numa tentativa de reforma ilustrada empreendida pelo pombalismo. Portanto, esta pesquisa corresponde ao período entre o confisco dos bens e o último administrador do período pombalino. A análise de diversos documentos dos administradores após o confisco permitiu algumas conclusões, em síntese, das dificuldades de administração, como a má administração por meio de desvios, corrupção e disputas locais. Como fonte foram utilizados os documentos oficiais da Biblioteca Digital Luso-brasileira e da publicação Documentos Interessantes para a História e Costume de São Paulo, disponível na Biblioteca Digital UNESP. Essas fontes compreendem relatórios oficiais, correspondências e procedimentos administrativos e permitiram apontar os debates e decisões em torno desse patrimônio.
O papel do Instituto Histórico na construção de memórias sobre a Baixada Fluminense (1971-1985)
Authors: Laurentino Eliana Santos , Fernandes Rui Aniceto
Published: February 2021

A proposta deste trabalho é apresentar como o Instituto Histórico da Câmara de Duque de Caxias (RJ), fundado em 1971, foi útil para edificar uma memória de “progresso” para o município, durante o período em que a cidade foi enquadrada como “área interesse de segurança nacional”. As ações do legislativo e do fortalecimento de imagens, com símbolos e comemorações no espaço, favoreceram a participação e o diálogo com regime político. O lugar de memória é aqui considerado no sentido proposto por Pierre Nora, que a memória não se constrói livremente, mas é alimentada por arquivos, aniversários e celebrações. A seleção de fontes incluiu os periódicos locais, como: o jornal Municipal e a Luta Democrática, bem como a produção realizada por Dalva Lazaroni, no período de gestão do Instituto Histórico, com o livro Esboço Histórico Geográfico do Município de Duque de Caxias (1978). A partir da análise das ações realizadas pelo espaço e a produção da diretora, foram encontrados indicativos do reconhecimento do lugar de poder e prestígio do instituto, e a aplicabilidade de projetos historiográficos na consolidação de projetos políticos, potencializando o lugar de produção como parte do processo de construção do território.
História Regional: novas perspectivas
Authors: Maleval Isadora Tavares , Atallah Cláudia , Cesco Susana
Published: February 2021

Apresentação. Revista Maracanan, PPGH-UERJ, Rio de Janeiro, n. 26 - "História Regional: novas perspectivas", p. 7-12, jan.-abr. 2021.
Facilitating cultural change in healthcare organisations
Authors: Wood Rachel Louise
Published: February 2021

The need for cultural change in healthcare organisations is well documented. There is a plethora of evidence to demonstrate the devastating impact of poor workplace culture on staff and patient outcomes. However, balanced against the significant financial pressures and a staffing crisis, cultural change is unlikely to be made a priority, despite the fact that many of the problems faced by organisations are compounded by poor workplace culture. The evidence demonstrates the positive difference cultural change can make, building staff confidence and encouraging innovation which, in turn, will result in greater efficiency and best use of limited funding. This article presents a simple model that may, when combined with other cultural tools, offer organisations a cost-effective and practical way to develop a positive workplace culture.
The impact of GP referrals on overcrowding in emergency departments and acute medicine
Authors: Abbasi Ayaz A , Khan Shams , Ameh Victor , Muhammad Ilyas
Published: February 2021

Background/Aims

A long-standing issue common to most emergency departments worldwide is overcrowding, and the UK is no exception. Overcrowding can have many adverse consequences, such as increased medical errors, decreased quality of care and poor patient outcomes. This service evaluation aimed to review the number of patients referred to acute specialties by their GPs and to evaluate the impact of these referrals on the flow of patients in and out of the emergency department and acute medicine.

Methods

GP referral letters were collected at an emergency department in Greater Manchester, England, between 15 May 2019 and 28 May 2019. A proforma was used by a consultant in acute medicine and a consultant in emergency medicine to evaluate each letter.

Result

A total of 139 GP referrals were received by the emergency department, of which 43 were to general medicine and 96 to other specialties. Of the latter, 54 cases were directed to the emergency department, 20 were directed to a different specialty and 23 did not have a specialty clearly specified. The majority of referrals were for gastrointestinal conditions or abdominal pain, with the next largest category being chest infections. Most of these patients were eventually seen in the trust's ambulatory assessment area to relieve pressure on the emergency department.

Conclusions

Planned and specific use of urgent care centres and ambulatory assessment areas can help to relieve pressure on emergency departments, but appropriate intervention at the primary care level is also necessary to improve patient flow.
Students’ Perceptions of an Intervention Course Designed to Raise Science-Related Career Awareness
Authors: Soobard Regina , Kotkas Tormi , Holbrook Jack , Rannikmae Miia
Published: February 2021

This longitudinal study focuses on evaluating grade 7-9 school students’ perceptions of intervention modules intended to be relevant, as well as promoting learning attributes to raise awareness of science-related careers. Students are taught through six purposely developed and designed career-related teaching–learning modules (C-TLMs). Each module is initiated by means of a career-related scenario, followed up by promoting conceptual science learning plus drawing attention to careers to which each module intends to relate. Student perceptions are obtained by means of a questionnaire after each module with respect to its relevance and also the mean by which the learning environment raise interest, enjoyment and motivation associated with career awareness. Outcomes show that, in general, students participating in this study agree that the developed C-TLMs are relevant and students value the learning experienced through the different module contexts. Nevertheless, student appreciation of the specific inclusion of career awareness components in the modules is mixed.
The role of urban agriculture for a resilient city
Authors: LE Hoang Tien , VO Thi Huong Ly , CHAU Ngoc Han
Published: February 2021

Humans are simultaneously facing challenges as climate change, epidemics and scarcity of food and water. It is estimated that by 2021 over 690 million of people will face hunger; by 2050 the global population will increase up to 10 billion with 68% of the population living in urban areas. By providing 30% of self-sufficient food in 2030, urban agriculture will be a practical concept to face these challenges. The work studies the role of agricultural land as a critical part for a resilient city. Parameters related to food production are also explored. As study case, this work aims to investigate the current food security of the Ho Chi Minh city (HCMC), offering productive green solutions at different scales from land-use planning, urban design to green roofs. For a production of 6.7 kg/day of vegetables a day, the costs of are approximately $10,000 for nearly 5.6 square meters of land; this points out A-Go-Gro technology as an effective measure for vertical farming. For example, 0.18 ha of green space can produce 2 tons of vegetables per day in the Lake View settlement (district 2 in HCMC). Moreover, due to green roofs, stormwater volumes directed into the sewer system are decreased by 65% and the penetration of electromagnetic radiation is reduced by 99.4%.

Loài người đang đồng thời đối mặt với những thách thức như biến đổi khí hậu, dịch bệnh, khan hiếm thực phẩm và nước. Ước tính đến năm 2021 có hơn 690 triệu người đói và đến năm 2050 dân số toàn cầu tăng lên gần 10 tỷ người, với 68% sống ở khu vực thành thị. Được sử dụng để tự cung tự cấp 30% lương thực vào năm 2030, nông nghiệp đô thị là một khái niệm hiệu quả cho những thách thức. Bài báo là nghiên cứu đất nông nghiệp như một phần quan trọng cho một thành phố có khả năng phục hồi. Các thông số liên quan đến sản xuất lương thực được nghiên cứu. Bài báo cũng tìm hiểu an ninh lương thực của thành phố Hồ Chí Minh hiện nay. Hơn nữa, bài báo đưa ra các giải pháp phủ xanh hiệu quả trên các quy mô khác từ quy hoạch sử dụng đất, thiết kế đô thị đến mái nhà xanh tại các hộ gia đình. Với chi phí 10.000 USD và gần 5,6 mét vuông đất trồng 6,7 kg rau mỗi ngày, công nghệ A-Go-Gro là một biện pháp hữu hiệu cho canh tác theo chiều dọc. Như vậy 0,18 ha không gian xanh có thể sản xuất 2 tấn rau mỗi ngày tại khu dân cư Lake View ở quận 2. Hơn nữa, bằng cách làm mái nhà xanh, nước mưa giảm đến 65% vào hệ thống cống và sự xâm nhập bức xạ điện từ giảm 99,4%.
Managed Care and Value-Based Payment: The Relationship Between Quality of Life Outcomes and Emergency Room Utilization
Authors: Friedman Carli
Published: February 2021

Although Medicaid managed care is a growing service model, there is a limited evidence base regarding quality and value-based payment standards for people with intellectual and developmental disabilities (IDD). This study examined the relationship between emergency room utilization and quality of life outcomes. We analyzed secondary Personal Outcome Measures quality of life and emergency room utilization data from 251 people with IDD. According to our findings, people with IDD with continuity and security in their lives and/or who participated in the life of the community had fewer emergency room visits, regardless of their impairment severity or dual diagnosis status. As such, the number of emergency room visits needed, and the potential expenditures associated, may be reduced by focusing on quality outcomes.
Development, Implementation, and Evaluation of an Advance Care Planning Program for Professionals in Palliative Care of People With Intellectual Disability
Authors: Voss Hille , Vogel Anique G.F.M , Wagemans Annemieke M.A , Francke Anneke L. , Metsemakers Job F.M. , Courtens Annemie M. , de Veer Anke J.E.
Published: February 2021

In this article we describe how an advance care planning (ACP) program was developed, implemented, and evaluated. Our aim was to improve ACP in palliative care for people with intellectual disability (ID). The program was based on 10 competencies needed for ACP and was developed in a co-design process with people with ID, relatives, and professionals. The program was implemented in six ID care organizations in the Netherlands and consisted of an information pack, a training course, and an implementation interview about implementing ACP. Professionals indicated that their competencies had improved, particularly regarding communication and the application of ACP as a standard element in palliative care practice. This program therefore seems helpful in training ID care professionals in the competencies needed for ACP.
Racial and Ethnic Disparities in Perceived Barriers to Health Care Among U.S. Adults With Intellectual and Developmental Disabilities
Authors: Li Henan , Parish Susan L. , Magaña Sandra , Morales Miguel A.
Published: February 2021

Barriers to health care access can greatly affect one's health status. Research shows that U.S. adults with intellectual and developmental disabilities (IDD) have poor health and face barriers such as long waits for appointments. However, whether barriers differ by race and ethnicity has not been examined. We conducted a secondary data analysis using the 2002–2011 Medical Expenditure Panel Survey dataset, and compared perceived barriers of community-living U.S. adults with IDD in three racial and ethnic groups (White, Black, and Latinx). Specifically, we examined the top reasons for not having usual source of care, delaying or foregoing medical care. For Black and Latinx adults with IDD, the most-mentioned reasons for not having usual source of care, delaying or foregoing medical care were “don't like/don't trust doctors,” “don't use doctors,” and “don't know where to get care.” In comparison, the White adults with IDD group's biggest perceived barriers were location and insurance related. All groups cited that being unable to afford care was a top reason for delaying or foregoing care. Policies/interventions to improve health care access in racial/ethnic minorities with IDD must first address the topic of developing trust between patients and the health professions. Insurance and the rising costs of care are also key areas that need attention.
Digital Collection: The Top Political Ads in American History
Authors: Franz Michael
Published: February 2021

Abstract: Political ads are much decried by voters, but campaigns know that they are critical means of reaching constituents and making direct claims about the positive and negatives of candidates on the ballot. Political ads are most common on television, in 30-second bites. But increasingly campaigns are turning to social media to spread paid messages. While these social media ads will become more common in cycles-to-come, how can we assess the scope of ads that have aired across the many decades of modern elections? Which ones have stood the test of time? This collection highlights 61 ads from 1754 to spring 2020, determined from feedback by experts in the field in a previous study published in  Advertising & Society Quarterly . The editors of  Advertising & Society Quarterly hope that this collection can be helpful to analyze and reflect on the role of political advertising in society, culture, history, and the economy.
Native Americans in Popular and Commercial Culture: An Interview with Paul Chaat Smith from the National Museum of the American Indian
Authors: Smith Paul Chaat , Timke Edward
Published: February 2021

Abstract: Paul Chaat Smith talks about his work as a curator at the Smithsonian Institution's National Museum of the American Indian (NMAI) in Washington, DC. He also covers how his Comanche heritage has influenced his personal and professional journey as a writer, curator, and critic of art and culture. Smith discusses other important topics: the history and early reception of the NMAI, his work as a curator, what the NMAI collects, the use of various terms of identity (e.g. American Indian, Native American, Indigenous), the diversity of Indian cultures and experiences, the American Indian Movement (AIM), activism today among American Indians, the Americans exhibit featuring images of Native Americans in popular and commercial culture throughout American history, the perpetuation of fantasy images of American Indians, cancel culture, Keep America Beautiful's 1971 "Crying Indian" public service announcement, who can represent and speak for Native Americans, the need to recognize positive elements in Native history, and advice for professors and students.
Multi-wavelength radiometric thermometry data processing algorithm based on the BFGS algorithm
Authors: Yu Kun , Guo Huige , Zhang Kaihua , Liu Yanlei , Liu Yufang
Published: February 2021

Multi-wavelength radiometric thermometry has a wide application prospect in many fields. However, due to unknown emissivity, the data processing algorithm remains a difficult problem. The Broyden–Fletcher–Goldfarb–Shanno (BFGS) algorithm is proposed to inverse true temperature and spectral emissivity without assuming the emissivity model. The BFGS algorithm can automatically identify the emissivity models of different trends. These simulation results show that given different initial emissivity has no significant influence on the inverse temperature and emissivity. Then, we select 0.5 as the initial emissivity and carry out the simulation experiments at 800 and 900 K, respectively. The maximum absolute error of temperature is less than 3.5 K and the computation time is less than 0.2 s. Thus, the algorithm has high precision and efficiency. Finally, the verification experiment indicates that the BFGS algorithm is effective and reliable. The proposed method can be applied to real-time temperature measurement in many industrial processes.
Tunable peak power square-wave pulse based on an all-PM thulium-doped mode-locked fiber laser
Authors: Han Long , Wang Tianshu , Song Guangbin , Ma Wanzhuo , Fu Qiang , Yang Qiaochu , Liu Xianzhu , Guo Yanyan , Jiang Huilin
Published: February 2021

Nanosecond dissipative soliton resonance pulse is a demonstration of an all polarization-maintaining (PM) thulium-doped fiber laser in a nonlinear amplifying loop mirror (NALM)-based figure-eight configuration. Each loop of the apparatus includes a controllable power amplifier. With increased amplifier power, pulse width broadens linearly from 3.6 to 13.5 ns, and maximum single pulse energy can reach 27.5 nJ. Interestingly, the output peak power presents two completely opposite proportional effects in terms of the variation of settings for two amplifiers, respectively. The experimental results show that the NALM loop plays an important role for tunable pulse duration, and the unidirectional ring part makes a significant contribution for power scaling.
Velocity property of an optical chain generated by the tightly focused femtosecond radially polarization pulse
Authors: Li Dong , Chen Xin , Yang Zhe , Zhang Wei , Zhao Jianlin
Published: February 2021

Based on the Richards–Wolf vector diffraction integration, we obtained the expressions of the intensity and velocity of femtosecond radially polarized pulses at the focus near a dielectric interface, and the pulses are modulated by an optical system consisting of diffractive optical elements (DOEs) and a high numerical aperture (NA) lens. The factors that affected the intensity distribution and velocity evolution of the three-dimensional optical capture structural pulse (optical chain) are also analyzed. These factors include the DOE structural parameters (bandwidth, phase difference between the rings), the interception ratio of incident beam, the NA, the central wavelength of pulses, and the refractive index of exiting medium. The results show that the velocity of the optical chain will increase with an increase in the DOE bandwidth or a decrease in the refractive index of the exiting medium, and the maximum of the optical chain velocity will decrease versus the NA. Furthermore, the dependence of the optical chain velocity on its intensity distribution is also revealed. The superluminal and subluminal can also be found during the propagation of the optical chain. The velocity distribution difference between bright and dark areas along the

z

axis is more conducive to distinguishing the trapping of the Rayleigh particles. We believe these interesting results have great potential to improve the space–time resolution to detect particle positions during high-speed optical trapping.
Nondissipative non-Hermitian dynamics and exceptional points in coupled optical parametric oscillators
Authors: Roy Arkadev , Jahani Saman , Guo Qiushi , Dutt Avik , Fan Shanhui , Miri Mohammad-Ali , Marandi Alireza
Published: February 2021

Engineered non-Hermitian systems featuring exceptional points (EPs) can lead to a host of extraordinary phenomena in diverse fields ranging from photonics, acoustics, opto-mechanics, and electronics to atomic physics. In optics, non-Hermitian dynamics are typically realized using dissipation and phase-insensitive gain accompanied by unavoidable fluctuations. Here, we introduce non-Hermitian dynamics of coupled optical parametric oscillators (OPOs) arising from phase-sensitive amplification and de-amplification, and show their distinct advantages over conventional non-Hermitian systems relying on laser gain and loss. OPO-based non-Hermitian systems can benefit from the instantaneous nature of the parametric gain, noiseless phase-sensitive amplification, and rich quantum and classical nonlinear dynamics. We show that two coupled OPOs can exhibit spectral anti-parity-time (anti-PT) symmetry and a EP between its degenerate and nondegenerate operation regimes. To demonstrate the distinct potentials of the coupled OPO system compared to conventional non-Hermitian systems, we present higher-order EPs with two OPOs, tunable Floquet EPs in a reconfigurable dynamic non-Hermitian system, and the generation of a squeezed vacuum around EPs, all of which are not easy to realize in other non-Hermitian platforms. We believe our results show that coupled OPOs are an outstanding non-Hermitian setting with unprecedented opportunities to realize nonlinear dynamical systems for enhanced sensing and quantum information processing.
Design and evaluation of a freeform lens-array for a structured light illumination
Authors: Essameldin Mahmoud , Binkele Tobias , Fleischmann Friedrich , Henning Thomas , Lang Walter
Published: February 2021

In illumination applications, freeform lens design starts by modeling the light source intensity, then determining the lens surface. Therefore, any change in the source intensity distribution directly impacts the created illuminance. Freeform lens-array could reduce the dependency between the illuminance pattern and the source intensity distribution. It divides the light source energy into separate beams; each creates the same illuminance pattern. All separated beams are superimposed at a distant target to generate the final illuminance pattern. This paper explains the design procedures of a freeform lens-array in detail, simulates the optical performance, and experimentally evaluates the working principle. Experiments evaluate using different light sources and using a variable illuminated aperture. Moreover, simulations compare the freeform lens-array to a traditional freeform lens.
Robust hybrid laser linewidth reduction using Si3N4-based subwavelength hole defect assisted microring reflector
Authors: Li Jiachen , Zhang Baoyu , Yang Sigang , Chen Hongwei , Chen Minghua
Published: February 2021

We demonstrate a hybrid laser with a low intrinsic linewidth of 34.2 Hz and a high fiber-coupled output power of 11.7 dBm, by coupling a

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-based subwavelength hole defect assisted microring reflector (SHDA-MRR) to a commercially available distributed feedback semiconductor laser. The proposed SHDA-MRR structure features an accurately controlled reflection response, with the manipulated modal coupling between two degenerate counterpropagating modes induced by a subwavelength hole defect embedded in the microring waveguide. With further joint optimization of cavity parameters, this

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SHDA-MRR structure is expected to reduce the laser intrinsic linewidth to a sub-hertz level. This work explores a low-cost and robust linewidth reduction scheme for the applications of high-speed coherent optical communications systems and high-resolution optical metrology.
Circular dichroism-like response of terahertz wave caused by phase manipulation via all-silicon metasurface
Authors: Li Jie , Zheng Chenglong , Wang Guocui , Li Jitao , Zhao Hongliang , Yang Yue , Zhang Zhang , Yang Maosheng , Wu Liang , Li Jining , Zhang Yating , Zhang Yan , Yao Jianquan
Published: February 2021

Chiral metasurfaces based on asymmetric meta-atoms have achieved artificial circular dichroism (CD), spin-dependent wavefront control, near-field imaging, and other spin-related electromagnetic control. In this paper, we propose and experimentally verify a scheme for achieving high-efficiency chiral response similar to CD of terahertz (THz) wave via phase manipulation. By introducing the geometric phase and dynamic phase in an all-silicon metasurface, the spin-decoupled terahertz transmission is obtained. The giant circular dichroism-like effect in the transmission spectrum is observed by using a random phase distribution for one of the circular polarization components. More importantly, the effect can be adjusted when we change the area of the metasurface illuminated by an incident terahertz beam. In addition, we also demonstrate the spin-dependent arbitrary wavefront control of the transmitted terahertz wave, in which one of the circularly polarized components is scattered, while the other forms a focused vortex beam. Simulated and experimental results show that this method provides a new idea for spin selective control of THz waves.
Analysis of the demand for gastronomic tourism in Andalusia (Spain)
Authors: Dancausa Millán Mª Genoveva , Millán Vázquez de la Torre Mª Genoveva , Hernández Rojas Ricardo
Published: February 2021

In recent years, gastronomy has become a fundamental motivation to travel. Learning how to prepare gastronomic dishes and about the raw materials that compose them has attracted increasing numbers of tourists. In Andalusia (region of southern Spain), there are many quality products endorsed by Protected Designations of Origin, around which gastronomic routes have been created, some visited often (e.g., wine) and others remaining unknown (e.g., ham and oil). This study analyses the profile of gastronomic tourists in Andalusia to understand their motivations and estimates the demand for gastronomic tourism using seasonal autoregressive integrated moving average (SARIMA) models. The results obtained indicate that the gastronomic tourist in Andalusia is very satisfied with the places he/she visits and the gastronomy he/she savours. However, the demand for this tourist sector is very low and heterogeneous; while wine tourism is well established, tourism focusing on certain products, such as olive oil or ham, is practically non-existent. To obtain a homogeneous demand, synergies or pairings should be created between food products, e.g., wine-ham, oil-ham, etc., to attract a greater number of tourists and distinguish Andalusia as a gastronomic holiday destination.
Information retrieval interfaces in virtual reality—A scoping review focused on current generation technology
Authors: Schleußinger Maurice
Published: February 2021

The Information Retrieval user experience has remained largely unchanged since its inception for computers and mobile devices alike. However, recent developments in Virtual Reality hardware (pioneered by Oculus Rift in 2013) could introduce a new environment for Information Retrieval. This paper reports the results of a Scoping Literature Review (PRISMA-ScR) by rigorously examining the entire body of relevant literature with reproducible methods. The following research questions are answered: “What prototypes and concepts of Virtual Reality Information Retrieval systems with current generation hardware exist?”, “How are user interaction and especially user input realised in these systems?”, “What Retrieval features are used in these systems?”, “How are search results displayed in these systems?” and “Can these VR IR systems compare to traditional (non-VR) IR systems?”. After querying Google Scholar, Scopus and Web of Science, 1042 documents were reviewed in depth. Key features and attributes of the systems are summarised and discussed. Sketches of the user interfaces are included as well. The 30 documents that were relevant to the research questions include 16 distinct systems or theories. They discuss and utilise several user input technologies, ranging from controllers, voice input or hand tracking. Although conventional retrieval features are less common, systems enable retrieval of literature, 3D objects, images, books and texts and arrange them in a virtual space (e.g. as grids, arcs or maps). Finally, many of these systems were compared to conventional counterparts through user evaluation (n = 10). Most found user task times to be shorter or equal (n = 5, n = 3). In the seven papers that measured user performance (rate of correct solutions), three reported better performance (one equal). Notably, users always were more satisfied with the Virtual Reality systems compared to conventional ones. Possible limitations of these evaluations are demographic selection and the quality of baseline systems (control).
Microvascular flow alterations in critically ill COVID-19 patients: A prospective study
Authors: Abou-Arab Osama , Beyls Christophe , Khalipha Abdelilah , Guilbart Mathieu , Huette Pierre , Malaquin Stéphanie , Lecat Benoit , Macq Pierre-Yves , Roger Pierre Alexandre , Haye Guillaume , Bernasinski Michaël , Besserve Patricia , Soriot-Thomas Sandrine , Jounieaux Vincent , Dupont Hervé , Mahjoub Yazine
Published: February 2021

Background

Data on microcirculatory pattern of COVID-19 critically ill patients are scarce. The objective was to compare sublingual microcirculation parameters of critically ill patients according to the severity of the disease.

Methods

The study is a single-center prospective study with critically ill COVID-19 patients admitted in ICU. Sublingual microcirculation was assessed by IDF microscopy within 48 hours of ICU admission. Microcirculatory flow index (MFI), proportion of perfused vessel (PPV), total vessel density (TVD), De Backer score (DBS), perfused vessel density (PVD) and heterogeneity index (HI) were assessed. Patients were divided in 2 groups (severe and critical) according to the World health organization definition.

Findings

From 19th of March to 7th of April 2020, 43 patients were included. Fourteen patients (33%) were in the severe group and twenty-nine patients (67%) in the critical group. Patients in the critical group were all mechanically ventilated. The critical group had significantly higher values of MFI, DBS and PVD in comparison to severe group (respectively, PaCO2: 49 [44–45] vs 36 [33–37] mmHg; p<0,0001, MFI: 2.8 ± 0.2 vs 2.5 ± 0.3; p = 0.001, DBS: 12.7 ± 2.6 vs 10.8 ± 2.0 vessels mm-2; p = 0.033, PVD: 12.5 ± 3.0 vs 10.1 ± 2.4 mm.mm-2; p = 0.020). PPV, HI and TVD were similar between groups Correlation was found between microcirculatory parameters and PaCO2 levels.

Conclusion

Critical COVID-19 patients under mechanical ventilation seem to have higher red blood cell velocity than severe non-ventilated patients.
Tolerance interval testing for assessing accuracy and precision simultaneously
Authors: Chiang Chieh , Hsiao Chin-Fu
Published: February 2021

Tolerance intervals have been recommended for simultaneously validating both the accuracy and precision of an analytical procedure. However, statistical inferences for the corresponding hypothesis testing are scarce. The aim of this study is to establish a whole statistical inference for tolerance interval testing, including sample size determination, power analysis, and calculation of p-value. More specifically, the proposed method considers the bounds of a tolerance interval as random variables so that a bivariate distribution can be derived. Simulations confirm the theoretical properties of the method. Furthermore, an example is used to illustrate the proposed method.
The presence of microorganisms in follicular fluid and its effect on the outcome of in vitro fertilization-embryo transfer (IVF-ET) treatment cycles
Authors: Usman Safiyya Faruk , Shuaibu Ibraheem Rais , Durojaiye Korede , Medugu Nubwa , Iregbu Kenneth Chukwuemeka
Published: February 2021

Objectives

To determine if the presence of microorganisms in follicular fluid of women undergoing in vitro fertilization-embryo transfer (IVF-ET) adversely affects the outcome of the treatment cycles.

Methods

Follicular fluid was collected from 86 women enrolled for IVF-ET at the National Hospital, Abuja from June 1, 2018 to December 1, 2018. Microscopy imaging and cultures were performed to identify bacteria and fungi in the follicular fluid and the vagina. Women with follicular fluid microorganisms were the test group while the controls were those without follicular fluid microorganisms. Fertilization and pregnancy rates were subsequently determined and their association with the presence of follicular fluid microorganisms was assessed using univariable and multivariable logistic regression modelling.

Results

The mean age and mean Body Mass Index (BMI) of the participants were 35(± 3.5) years and 28(± 4.9) kg/m2respectively. Bacteria and fungi were isolated in 17% of the follicular fluid samples collected (n = 15/86). Most common isolates were Streptococcus spp. (n = 4/15),Staphylococcus aureus(n = 7/15), Enterococcus spp. (n = 4/15), Lactobacillus species (n = 2/15) andCandida albicans(n = 2/15). There was no statistically significant difference in the fertilization rates (adjusted odds ratio [AdjOR] 0.55, 95% confidence interval [CI] 0.04–7.34; P = 0.10) and pregnancy rates (AdjOR 4.02, 95% CI 0.56–28.92; P = 0.19) between the group of women with positive follicular fluid bacterial /fungal colonization as compared against those with negative follicular fluid colonization.

Conclusion

Isolation of microorganisms from follicular fluid did not adversely affect fertilization and pregnancy rates following IVF-ET treatment cycles at the fertility centre of National Hospital, Abuja.