bluuebunny/crossref_metadata_2025 huggingface dataset:
Unleashing the mysterious link between COVID-19 and a famous childhood vasculitis: Kawasaki disease
Authors: AbdelMassih Antoine Fakhry , AbdelAzeam Aisha Said , Ayad Aya , Kamel Aya Yasser , Khalil Ayah , Kotb Basma , Waheed Dina , Menshawey Esraa , Sefein Fady , Taha Farah , Ismail Habiba-Allah , Osman Ibrahim , Iskander John , El Wakil Lama , Rashad Lara , Arsanyous Mariem Badr , El Shershaby Meryam , Mansour Mina , Ashraf Mirette , Hafez Nada , Abuzeid Nadeen Mohamed , AbdElSalam Noheir Mahmoud-Nashaat , Hafez Nouran Gamal , Youssef Nourhan , Hozaien Rafeef , Saeed Rana , Kamel Dina , AbdelHameed Manal Ahmed , Ali Salma
Published: July 2020

Background

Coronavirus disease 2019 (COVID-19) emerged as a small outbreak in Wuhan rapidly progressing into the deadliest pandemic since the Spanish flu of 1918. The disease was deemed trivial in children, until the reporting, few days ago, of an emerging pediatric multi-inflammatory syndrome mimicking Kawasaki disease (KD).

Main body

This report reveals that coronaviridae were implicated in induction of several post-infectious vasculitides, namely, KD, AHEI, and HSP. This occurs in genetically susceptible individuals to vascular inflammation. Shared genetic susceptibilities between KD and CoV include genes encoding for CD 40, HLAB-15:03, and ACE. This leads to augmented inflammation with hypersecretion of cytokines especially IL-6.

Conclusion

The revealed relationships between KD and CoV can help to predict the risk of KD in COVID-19 patients through screening levels of upregulated cytokines. It might also signify that classic treatment of KD with IVIG might need to be replaced with anti-cytokine therapy in COVID-19 patients.
Navigating Tensions of Research and Teaching: Biology Graduate Students’ Perceptions of the Research–Teaching Nexus within Ecological Contexts
Authors: Reid Joshua W. , Gardner Grant E.
Published: July 2020

This article presents data from a cross-sectional study on biology graduate students’ perceptions of the research-teaching nexus (RTN). Findings indicate that the majority of biology graduate students hold synergistic views of the RTN but receive mixed messages about this relationship from others.
Female In-Class Participation and Performance Increase with More Female Peers and/or a Female Instructor in Life Sciences Courses
Authors: Bailey E. G. , Greenall R. F. , Baek D. M. , Morris C. , Nelson N. , Quirante T. M. , Rice N. S. , Rose S. , Williams K. R.
Published: July 2020

Female students are less likely to participate in class than male peers in life sciences courses of all levels, but they are more likely to participate in classrooms with more female peers. Female students earn lower final course grades than males in classes taught by a male instructor and/or when female students are in the minority.
Safety and Efficacy of the Combination of Propofol and Ketamine for Procedural Sedation/Anesthesia in the Pediatric Population: A Systematic Review and Meta-analysis
Authors: Hayes Jason A. , Aljuhani Talal , De Oliveira Kyle , Johnston Bradley C.
Published: July 2020

BACKGROUND:

Drugs such as propofol and ketamine are used alone or in combination to provide sedation for medical procedures in children. The purpose of this systematic review was to compare the safety and effectiveness of propofol and ketamine to other drug regimens.

METHODS:

We searched Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews (CDSR), Web of Science, and the grey literature (meta-Register of Controlled Trials, ClinicalTrials.gov, and Google Scholar) for randomized controlled studies comparing intravenous propofol and ketamine to any other single or combination drug regimen administered to children undergoing diagnostic or therapeutic procedures. Meta-analyses were performed for primary (hemodynamic and respiratory adverse events) and secondary outcomes using RevMan 5.3. We assessed the risk of bias and the certainty (quality) evidence for all outcomes using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology.

RESULTS:

Twenty-nine studies were included for analysis. Based on low-to-moderate quality evidence, we concluded that the use of propofol and ketamine may result in a slight-to-small reduction in the risk of hypotension, bradycardia, and apnea, and a slight increase in the risk of tachycardia, hypertension, and other respiratory adverse events, such as cough or laryngospasm. The ratio of propofol to ketamine and comparator drug regimen subgroups effects were important for desaturation and some secondary outcomes.

CONCLUSIONS:

The use of propofol and ketamine had a minimal effect on the incidence of adverse events and other secondary outcomes. Large-scale studies are required to more accurately estimate adverse event rates and the effects of propofol and ketamine on patient-important outcomes.
Balloon Pump Counterpulsation Part II: Perioperative Hemodynamic Support and New Directions
Authors: González Laura S. , Chaney Mark A.
Published: July 2020

Intraaortic balloon pump (IABP) counterpulsation, introduced more than 50 years ago, remains the most commonly utilized mechanical circulatory support device for patients with cardiogenic shock and myocardial ischemia, despite lack of definitive proof regarding its outcome in these patients. Part I of this review focused on the history of counterpulsation, physiologic principles, technical considerations, and evidence for its use in cardiogenic shock; Part II will discuss periprocedural uses for IABP counterpulsation and review advances in technology, including the emergence of alternative mechanical circulatory support devices that have influenced IABP utilization.
The Current State of Combined Pediatric Anesthesiology–Critical Care Practice: A Survey of Dual-Trained Practitioners in the United States
Authors: Welch Timothy P. , Kilbaugh Todd J. , McCloskey John J. , Juriga Lindsay L. , Abdallah Arbi Ben , Fehr James J.
Published: July 2020

Background:

Combined practice in pediatric anesthesiology (PA) and pediatric critical care medicine (PCCM) was historically common but has declined markedly with time. The reasons for this temporal shift are unclear, but existing evidence suggests that length of training is a barrier to contemporary trainees. Among current practitioners, restriction in dual-specialty practice also occurs, for reasons that are unknown at present. We sought to describe the demographics of this population, investigate their perceptions about the field, and consider factors that lead to attrition.

METHODS:

We conducted a cross-sectional, observational study of physicians in the United States with a combined practice in PA and PCCM. The survey was distributed electronically and anonymously to the distribution list of the Pediatric Anesthesia Leadership Council (PALC) of the Society for Pediatric Anesthesia (SPA), directing the recipients to forward the link to their faculty meeting our inclusion criteria. Attending-level respondents (n = 62) completed an anonymous, 40-question multidomain survey.

RESULTS:

Forty-seven men and 15 women, with a median age of 51, completed the survey. Major leadership positions are held by 44%, and 55% are externally funded investigators. A minority (26%) have given up one or both specialties, citing time constraints and politics as the dominant reasons. Duration of training was cited as the major barrier to entry by 77%. Increasing age and faculty rank and lack of a comparably trained institutional colleague were associated with attrition from dual-specialty practice. The majority (88%) reported that they would do it all again.

CONCLUSIONS:

The current cohort of pediatric anesthesiologist–intensivists in the United States is a small but accomplished group of physicians. Efforts to train, recruit, and retain such providers must address systematic barriers to completion of the requisite training and continued practice.
Lgl cortical dynamics are independent of binding to the Scrib-Dlg complex but require Dlg-dependent restriction of aPKC
Authors: Ventura Guilherme , Moreira Sofia , Barros-Carvalho André , Osswald Mariana , Morais-de-Sá Eurico
Published: July 2020

Apical-basal polarity underpins the formation of epithelial barriers that are crucial for metazoan physiology. Although apical-basal polarity is long known to require the basolateral determinants Lethal Giant Larvae (Lgl), Discs Large (Dlg) and Scribble (Scrib), mechanistic understanding of their function is limited. Lgl plays a role as an aPKC inhibitor, but it remains unclear whether Lgl also forms complexes with Dlg or Scrib. Using fluorescence recovery after photobleaching, we show that Lgl does not form immobile complexes at the lateral domain of Drosophila follicle cells. Optogenetic depletion of plasma membrane PIP2 or dlg mutants accelerate Lgl cortical dynamics. However, Dlg and Scrib are required only for Lgl localization and dynamic behavior in the presence of aPKC function. Furthermore, light-induced oligomerization of basolateral proteins indicates that Lgl is not part of the Scrib-Dlg complex in the follicular epithelium. Thus, Scrib and Dlg are necessary to repress aPKC activity in the lateral domain but do not provide cortical binding sites for Lgl. Our work therefore highlights that Lgl does not act in a complex but in parallel with Scrib-Dlg to antagonize apical determinants.
Interplay between actomyosin and E-cadherin dynamics regulates cell shape in the Drosophila embryonic epidermis
Authors: Greig Joshua , Bulgakova Natalia A.
Published: July 2020

Precise regulation of cell shape is vital for building functional tissues. Here, we study the mechanisms that lead to the formation of highly elongated anisotropic epithelial cells in the Drosophila epidermis. We demonstrate that this cell shape is the result of two counteracting mechanisms at the cell surface that regulate the degree of elongation: actomyosin, which inhibits cell elongation downstream of RhoA (Rho1 in Drosophila) and intercellular adhesion, modulated via clathrin-mediated endocytosis of E-cadherin (encoded by shotgun in flies), which promotes cell elongation downstream of the GTPase Arf1 (Arf79F in Drosophila). We show that these two mechanisms do not act independently but are interconnected, with RhoA signalling reducing Arf1 recruitment to the plasma membrane. Additionally, cell adhesion itself regulates both mechanisms – p120-catenin, a regulator of intercellular adhesion, promotes the activity of both Arf1 and RhoA. Altogether, we uncover a complex network of interactions between cell–cell adhesion, the endocytic machinery and the actomyosin cortex, and demonstrate how this network regulates cell shape in an epithelial tissue in vivo.
The Journey to In Vivo Synthetic Chemistry: From Azaelectrocyclization to Artificial Metalloenzymes
Authors: Tanaka Katsunori , Vong Kenward
Published: July 2020

The goal of this account is to detail the steps taken by our group for the development of glycosylated artificial metalloenzymes (GArMs), which we have used in our endeavors to develop examples of in vivo synthetic chemistry. To accomplish this, we have had to combine technologies developed over the course of a decade that range from protein ligation methodologies, identification of glycan-dependent targeting modules, and the development of functional biocatalysts. As an end result, we have begun to show the early framework for GArM complexes and their potential towards creating novel biotechnological tools and therapeutic applications.
Cointegração e previsibilidade de abordagens VECM para o Ibovespa
Authors: Pereira Marcos Vinicius Lopes , De Araújo Leonardo Carneiro , Iquiapaza Robert Aldo
Published: July 2020

A presente pesquisa compara modelos multivariados aplicados à análise da série temporal do Ibovespa. Variáveis macroeconômicas, commodities e índices de mercado como regressores sugeridos pela literatura. A abordagem escolhida faz uso do modelo vetor de correção de erros (VECM) em conjunto com testes de raiz unitária e cointegração, robustos à heteroscedasticidade. O impacto de turbulências econômicas, nacionais e internacionais, foi controlado em função dos ciclos recessivos no Brasil e nos Estados Unidos e do período eleitoral brasileiro. Em geral, os modelos avaliados não conseguiram atender aos pressupostos da estimação, possuem baixo poder explicativo e não apresentaram relação significativa entre o Ibovespa e variáveis dependentes. Entretanto, foram observados indícios de que relações de longo prazo possam existir sem que isso implique em acurácia preditiva no curto prazo.
Board of directors, performance and firm value in Brazilian listed state-owned enterprises
Authors: Coletta Carolina , Arruda de Souza Lima Roberto
Published: July 2020

This paper investigates the relationship between the board of directors' structure and firm performance and the value of Brazilian listed state-owned enterprises (SOEs), from 2002 to 2017, totaling 327 observations using an unbalanced panel data with fixed and random effects regressions. The evolution of corporate governance practices adopted by the boards is presented for this period, using a Board Structure Index (BSI). The results indicate a significant positive relation between the board's structure and firm performance, measured by ROE and ROA, and firm value, measured by Tobin's q. These findings are consistent with corporate governance literature, in the sense that the board's role of monitoring management reduces agency conflicts. The results also show an improvement in adopting corporate governance practice on Brazilian SOEs' boards over the last decade.
New records of rare species in the Mediterranean Sea (November 2020)
Authors: ARTICLE B COLLECTIVE
Published: July 2020

-
Case Report: Heparin-induced thrombocytopenia in a patient with COVID-19
Authors: Aly Ragia , Gupta Sachin , Gupta Sorab , Singh Balraj , Goyal Abhinav , Kalathil Sheila
Published: July 2020

With the spread of the novel coronavirus disease of 2019 (COVID-19) worldwide and associated high incidence of thromboembolic complications, the use of heparin is on the rise. It therefore is crucial to identify patients with contraindications for heparin. Heparin-induced thrombocytopenia (HIT) is a life-threatening complication of exposure to heparin. We report a 66-year-old woman, who was admitted to the hospital with COVID-19 infection. Her course was complicated by pulmonary embolism and dialysis catheter thrombosis. Our patient had a known history of HIT. Treatment of this patient with heparin would have been catastrophic. The COVID-19 pandemic has overwhelmed healthcare systems and is causing a global health crisis. Nevertheless, this case serves as a reminder of the importance of making every effort to obtain thorough history and review of records of every patient.
The Effectiveness of New Inquiry-Based Learning (NIBL) for Improving Multiple Higher-Order Thinking Skills (M-HOTS) of Prospective Chemistry Teachers
Authors: Mitarlis Mitarlis , Ibnu Suhadi , Rahayu Sri , Sutrisno Sutrisno
Published: July 2020

New Inquiry-Based Learning (NIBL) was developed to improve students’ multiple higher-order thinking skills (MHOTS), such as thinking critically, analytically, creatively, and practically (CACP). This study aimed to examine the increase of students’ MHOTS ability, their perceptions of the NIBL model, and the contribution of the NIBL model to the learning outcomes.  A quasi-experiment of the nonequivalent control group design was implemented in this study. Research subjects were university students majoring in chemistry education and enrolling in the Organic Chemistry course. The experiment and the control groups consisted of 34 and 32 students, respectively. The collected data were analyzed by using t-test and ANCOVA procedures. N-Gain scores were calculated to measure the differences in the increase in learning outcomes. Eta square values measured the contribution of NIBL. The results of this study revealed that there were differences in the learning outcomes of the experiment and control group. The CACP thinking skills and the mastery of organic chemistry concepts of the experiment group increased significantly. The N-Gain scores of practical thinking skills aspect were on medium category, and for critical, analytical, and creative thinking, as well as for mastery of organic chemistry concepts were on high categories. For the control group, the N-Gain scores of all categories were on low or medium categories. The NIBL model effectively improved the prospective chemistry teachers’ M-HOTS in terms of CACP thinking skills and contributed significantly to the increase in the students’ mastery of organic chemistry concepts.
A Comparison between Competencies of Teachers and Students of Teacher Education in Recognizing Artistically Gifted Students
Authors: Brajcic Marija , Kuscevic Dubravka , Lazeta Marijana
Published: July 2020

School system has not proven successful in educating gifted students. Artistically gifted students are a group of students requiring special education approach. The aim of this paper was to explore the extent to which classroom teachers and students as future teachers are able to identify artistically gifted students. The study involved a total of 160 respondents, among which 80 classroom teachers and 80 students at the Faculty of Humanities and Social Sciences, Department of Teacher Education in Split. The results showed statistically significant differences in the identification of artistically gifted students between groups of teachers and groups of students, future teachers. The results showed that there is a statistically significant difference in the assessment of several factors of giftedness of students in the surveyed teachers compared to students of Teacher Education. A statistically significant difference is present in Factor 1 (Art Abilities) where p (0.00) <0.05, and in Factor 3 (Motivation in Artistic Expression) where p (0.00) <0.05 and in Factor 4 (Use of Fine Arts) where p (0.04) <0.05. A statistically significant difference between students and teachers is not present in Factor 2 (Art Interests) where p (0.78)> 0.05. Furthermore, the results showed that teachers and students of Teacher Education share the opinion that gifted students will have a high level of learning, possess a large number of artistic ideas and show interest in figurative and abstract forms of artwork.
A Pilot Result on Applying the Vocational School-based Program for Vietnamese High School Students based on a New Individual Guidance Approach
Authors: Le Duy-Hung , Tran-Thi Thu-Thuy , Cao Xuan-Hai , Giang Thien-Vu
Published: July 2020

Vocational orientation is a concerned topic in the Vietnamese new general education program. However, the current high school vocational programs have not yet met the need for innovation in the student competence development orientation, thus leading to high school vocational orientation has not been effective. This study proposes a vocational school-based program approached from a new individual guidance. By using the pre-experiment and post-experiment questionnaire to evaluate the feasibility and effectiveness of the proposed program to the quality of vocational orientation, the results showed that students’ awareness of vocational school-based programs changed in a positive direction. The proposed program proves its effectiveness when applied in schools by combining the practical career experience and vocational counseling, or the combination of individual experience and social interaction in choosing a suitable career. This finding overcomes the disadvantages of the old vocational school-based program and can be applied to adapt the student competence development orientation in the Vietnamese general education program.
Öğrenme Stiline Dayalı Eğitimin Akademik Başarıya Etkisi
Authors: DİKMEN Melih , TUNCER Murat
Published: July 2020

Bu araştırmanın amacı öğretmen adaylarının baskın öğrenme stillerine göre yapılandırılmış öğretimin, akademik başarıları üzerindeki etkisini incelemektir. Araştırmada öntest-sontest deney-kontrol gruplu yarı deneysel desen kullanılmıştır. Araştırmada veri toplama aracı olarak araştırmacılar tarafından geliştirilen Başarı Testi ile Riechmann ve Grasha tarafından geliştirilen ve Kılıç (2011) tarafından Türkçeye uyarlanan Grasha ve Riechmann Öğrenme Stilleri Ölçeği kullanılmıştır. Araştırmaya Fırat Üniversitesi Fen Bilgisi ve Türkçe Öğretmenliği lisans programındaki 109 öğretmen adayı (94 kadın ve 15 erkek) katılmıştır. Araştırmada, deney ve kontrol grupları yansız atama sonucunda oluşturulmuştur. Öğrenme stillerine dayalı öğretimin yapıldığı deney grubu öğretmen adaylarının akademik başarılarının, kontrol grubu öğretmen adaylarına göre anlamlı düzeyde yüksek olduğu belirlenmiştir. Öğrenme stiline dayalı öğretimin, akademik başarı üzerinde orta düzeyde etki gücüne sahip olduğu görülmektedir. Bu doğrultuda öğretmen eğitimindeki niteliği artırmak amacıyla öğretmen adaylarının baskın öğrenme stillerinin dikkate alınması önemli bir değişken olarak görülebilir. Yükseköğretim kurumlarında öğretmen adaylarının öğrenme stillerine uygun öğretim programları hazırlanması ve uygulanması önerilmektedir.
Broadband dual-mode 2  ×  2 3  dB multimode interference couplers with a shallowly etched multimode section
Authors: Ye Chaochao , Zhang Ming , Shi Yaocheng , Dai Daoxin
Published: July 2020

A broadband dual-mode

2

×

2

3

d
B

power splitter on silicon is proposed by utilizing multimode interference (MMI) couplers with a shallowly etched multimode region. The present MMI coupler is designed optimally to be with reduced phase errors for all the excited higher-order modes in the MMI region by engineering the refractive-index profile with the assistance of a shallowly etched multimode region. Simulation results show the device works well for the

T
E

0

and

T
E

1

input modes over the C-band. For the

T
E

0

input mode, the excess losses (ELs) and the imbalances (IBs) are, respectively, less than 0.4 and 0.12 dB in the wavelength range of 1.5–1.6 µm, while the ELs and the IBs for the

T
E

1

input mode are, respectively, less than 0.5 and 0.2 dB in the wavelength range of 1.53–1.58 µm. Besides, the intermode cross-talk is less than

−
22

d
B

for

T
E

0

and

T
E

1

modes in the wavelength range of 1.5–1.6 µm. The proposed dual-mode MMI coupler can be extended for more than two input modes.
Design of all-optical D flip-flop using photonic crystal waveguides for optical computing and networking
Authors: Rao Dalai Gowri Sankar , Palacharla Venkatrao , Swarnakar Sandip , Kumar Santosh
Published: July 2020

The performance of an ultra-compact all-optical D flip-flop using photonic crystal waveguides is numerically analyzed and examined by optimized parameters such as refractive index and silicon rod radius. In the field of optical networking and computing, flip-flops are used to reduce the complexity of digital circuits. The phenomenon of optical interference effect is used to implement a D flip-flop at a wavelength of 1550 nm. This structure is designed using T-shaped waveguides without using non-linear material. The proposed design is small, has low insertion losses of 0.087 dB when operated at low power level, and provides high contrast ratio of 25 dB and transmission ratio of more than 96%.
Small footprint symmetrical graphene hybrid plasmonic waveguides for high-speed broadband optical modulation
Authors: Hasan K. B. M. Rakib , Islam Md. Asiful , Alam M. Shah
Published: July 2020

In this work, nanowire-based symmetrical graphene hybrid plasmonic waveguides for possible broadband optical modulation have been proposed. The full-vectorial finite element method has been employed to analyze the modal properties and modulation characteristics of the proposed structures. The fundamental supermode supported by these geometries is evolved from a near-field coupling between metallic and dielectric nanowires. Here, the strong optical capacitance effect in the low-index dielectric gap region has been exploited to enhance light–graphene interaction in the subwavelength device size. Thus, the optical absorption of graphene significantly increases. Therefore, the structures even with their small footprints offer a very high extinction ratio and small energy consumption per bit (as low as 0.9 fJ/bit), simultaneously with appreciably high modulation bandwidth at the telecommunication wavelength. A substantially small variation of modulation performance for a broad range of operation wavelength and gap widths suggest their broadband operability. Furthermore, the modulation performance has been studied incorporating the optical anisotropy of graphene. Thus, the proposed waveguides show a good promise in high-speed broadband optical modulation.
Asymmetric enhancement of N2+ lasing in intense, birefringence-modulating elliptical laser fields
Authors: Fu Yao , Chen Shanming , Wang Siqi , Zhang Wei , Yao Danwen , Zang Hongwei , Li Helong , Xu Huailiang
Published: July 2020

We experimentally demonstrate an asymmetric enhancement of the N2+ lasing at 391 nm for the transition between the B2Σ
u
+ (v = 0) and X2Σ
g
+ (v” = 0) states in an intense laser field with the ellipticity,
ε
, modulated by a 7-order quarter-wave plate (7-QWP). It is found that when the 7-QWP is rotated from α = 0 to 90°, where α is the angle between the polarization direction of the input laser and the slow axis of the 7-QWP, the intensity of the 391-nm lasing is optimized at
ε ∼
0.3 with α
∼
10°-20° and 70°-80° respectively, but the optimization intensity at α
∼
10°-20° is about 4 times smaller than that at α
∼
70°-80°. We interpret the asymmetric enhancement based on a post-ionization coupling model, in which the birefringence of the 7-QWP induces an opposite change in the relative amplitudes of the ordinary (
Eo
) and extraordinary (
Ee
) electric components under the two conditions, so that the same temporal separation of
Eo
and
Ee
leads to a remarkably different coupling strength for the population transfer from the X2Σ
g
+ (v ”=0) to A2Πu (v ’=2) states.
Control of slow-light effect in a metamaterial-loaded Si waveguide
Authors: Tanaka Makoto , Amemiya Tomohiro , Kagami Hibiki , Nishiyama Nobuhiko , Arai Shigehisa
Published: July 2020

A metamaterial is an artificial material designed to control the electric permittivity and magnetic permeability freely beyond naturally existing values. A promising application is a slow-light device realized using a combination of optical waveguides and metamaterials. This paper proposes a method to dynamically control the slow-light effect in a metamaterial-loaded Si waveguide. In this method, the slow-light effect (i.e., group index) is controlled by changing the phase of the control light incident on the device from a direction opposite to that of the signal light. The group index of the device could be continuously controlled from 63.6 to 4.2 at a wavelength of 1.55 µm.
Modeling and improving the output power of terahertz master-oscillator power-amplifier quantum cascade lasers
Authors: Zhu Haiqing , Zhu Huan , Yu Chenren , Chang Gaolei , Wang Fangfang , Chen Jianxin , Li Lianhe , Davies A. Giles , Linfield Edmund H. , Tang Zhou , Chen Pingping , Lu Wei , Xu Gangyi , He Li
Published: July 2020

A model based on carrier rate equations is proposed to evaluate the gain saturation and predict the dependence of the output power of a terahertz master-oscillator power-amplifier quantum cascade laser (THz-MOPA-QCL) on the material and structure parameters. The model reveals the design rules of the preamplifier and the power extractor to maximize the output power and the wall-plug efficiency. The correction of the model is verified by its agreement with the experiment results. The optimized MOPA devices exhibit single-mode emission at ∼ 2.6 THz with a side mode suppression ratio of 23 dB, a pulsed output power of 153 mW, a wall-plug efficiency of 0.22%, and a low divergence angle of ∼6°×16°, all measured at an operation temperature of 77 K. The model developed here is helpful for the design of MOPA devices and semiconductor optical amplifiers, in which the active region is based on intersubband transitions.
Designing conformal cloaks by manipulating structures directly in the physical space
Authors: Wang Zhanyi , Liu Yichao , Cheng Tianhang , Sun Fei , He Sailing
Published: July 2020

The method to elaborately design the refractive index profile in the lower Riemann sheet of Zhukovski transformation plays an important role in the performance of this kind of conformal cloaks. However, for most proposed schemes, the mathematical calculations are complex. Here, we propose a more convenient method to design conformal cloaks by manipulating structures directly in the physical space. The designed cloak only needs symmetrical metal boundaries filled with normal dielectrics (refractive index ranges from 1 to 2) in the ‘circular branch cut’, which would be more feasible for future experimental implementation. Numerical simulations are performed by using the finite element method to validate our theoretical analysis.
Single-shot reconstruction of the density profile of a dense atomic gas
Authors: Mordini C. , Trypogeorgos D. , Wolswijk L. , Lamporesi G. , Ferrari G.
Published: July 2020

Partial transfer absorption imaging (PTAI) of ultracold atoms allows for repeated and minimally-destructive measurements of an atomic ensemble. Here, we present a reconstruction technique based on PTAI that can be used to piece together the non-uniform spatial profile of high-density atomic samples using multiple measurements. We achieved a thirty-fold increase of the effective dynamic range of our imaging, and were able to image otherwise saturated samples with unprecedented accuracy of both low- and high-density features.
Ultrawide-bandwidth on-chip spectrometer design using band-pass filters
Authors: Nikbakth Hamed , Karabiyik Mustafa , Akca B. Imran
Published: July 2020

Here, we present the design and simulation of an ultrawide-bandwidth on-chip spectrometer that can be used in various applications, e.g. spectral tissue sensing. It covers 1200 nm wavelength range (400 nm-1600 nm) with 2 nm spectral resolution. The overall design size is only 3 × 3 cm2. The ultra-wide spectral range is made possible by using novel on-chip band-pass filters for the coarse wavelength division. The fine resolution is provided by the arrayed waveguide gratings. The band-pass filter is formed by using bend waveguides and adiabatic full-couplers. The additional loss caused by the band-pass filter is relatively small. The proposed spectrometer covers entire 400 nm-1600 nm range continuously with low crosstalk values. We envision that this design can be used in several different applications including food safety, agriculture, industrial inspection, optical imaging, and biomedical research.
Self-assembled micropillars fabricated by holographic femtosecond multi-foci beams forin situ trapping of microparticles
Authors: Hu Yanlei , Feng Wenfei , Xue Cheng , Lao Zhaoxin , Ji Shengyun , Cai Ze , Zhu Wulin , Li Jiawen , Wu Dong , Chu Jiaru
Published: July 2020

Dynamic self-assembly of micropillars has found wide applications in targeted trapping, micro-crystallization and plasmonic sensing. Yet the efficient fabrication of micropillars array with high flexibility still remains a grand challenge. In this Letter, holographic femtosecond laser multi-foci beams (fs-MFBs) based on a spatial light modulator (SLM) is adopted to efficiently create micropillars array with controllable geometry and spatial distribution by predesigning the computer-generated holograms (CGHs). Based on these micropillars array, diverse hierarchical assemblies are formed under the evaporation-induced capillary force. Moreover, taking advantage of the excellent flexibility and controllability of fs-MFBs, on-demand one-bead-to-one-trap of targeted microspheres at arbitrary position is demonstrated with unprecedentedly high capture efficiency, unfolding their potential applications in the fields of microfluidics and biomedical engineering.
Asymmetrical bidirectional optical wireless communication system based on a transmissive 1D LC-SLM for NG-PON2
Authors: Chou Hsi-Hsir , Huang Wei-Ta
Published: July 2020

An asymmetric bidirectional optical wireless communication (B-OWC) system using optical fibers as the transmitter and receiver and capable of wavelength switching is proposed for next generation passive optical network stage two (NG-PON2) extension to home area network (HAN), without optical/electrical (O/E) and electrical/optical (E/O) conversions, which is based on a transmissive “floating” pixel size one-dimensional (1D) liquid crystal spatial light modulator (LC-SLM) at the access node (AN) and a modulated retroreflector (MRR) at the terminal user (TU). The utilization of a reflective grating element and a low-cost LC-SLM in the AN offers a high flexibility of beam steering and wavelength selection in the scenario of B-OWC. Instead of a light source used at conventional TU, a MRR was employed at a TU in order to improve the problems of the power consumptions, alignment difficulties, wavelength contentions, and cost of the TUs. Downlink and uplink data transmissions at a link speed over 2.5 Gbits/s, using wavelengths between

1590

∼

1603

n
m

and

1524

∼

1544

n
m

, respectively, corresponding to the downlink and uplink wavelengths specified by the NG-PON2 standard, have been experimentally demonstrated successfully, with quality factors (

Q

-factors) beyond the forward error correction limit (

Q

-

f
a
c
t
o
r

=

16.9

d
B

, bit error

r
a
t
e

=

10

−
12

).
Design and analysis of photonic crystal fiber plasmonic refractive Index sensor for condition monitoring of transformer oil
Authors: Paul Alok Kumar
Published: July 2020

This paper presents an octagonal photonic crystal fiber based plasmonic refractive index (RI) sensor using graphene to measure the moisture content in transformer oil. For better insulation, moisture content in transformer oil needs to be measured, as the moisture content degrades the insulation property of the oil. Basically, the proposed sensor is able to detect the change in RI of the oil as the moisture content changes the RI. This work is numerically simulated by a finite element method-based simulation tool and the simulation results are processed using a MATLAB environment to understand the performance. Using the proposed sensor, the maximum possible amplitude sensitivity can be obtained as 31,240 RIU-1 and 30,830 RIU-1 for the x- and y-polarized modes, respectively. Besides, the proposed sensor has also found the figure of merit (FOM) to be 5,000. Both the results are found to be highest to date (to the best of my knowledge). The novelty of this work is the idea of measuring the moisture content of transformer oil using graphene plasmonic RI sensor, the high FOM, and the highest amplitude sensitivity.
Mode selection and high-quality upconversion lasing from perovskite CsPb2Br5 microplates
Authors: Liu Zhengzheng , Wang Chunwei , Hu Zhiping , Du Juan , Yang Jie , Zhang Zeyu , Shi Tongchao , Liu Weimin , Tang Xiaosheng , Leng Yuxin
Published: July 2020

In recent years, halide perovskite nanostructures have had great advances and have opened up a bright future for micro/nanolasers. However, upconversion lasing by two-photon excitation with mode selection and high quality factor in one device is still rarely reported. Herein, two lasing modes are demonstrated in the all-inorganic perovskite

CsPb
2

Br
5

microplates with subwavelength thickness and uniform square shape. The net optical gain is quickly established in less than 1 ps and persists more than 30 ps, revealed by ultrafast transient absorption spectroscopy. The temperature-dependent low-threshold amplified spontaneous emission confirms the net gain for stimulated emission with a high characteristic temperature of 403 K, far surpassing the all-inorganic

CsPbBr
3

semiconductor gain media. Remarkably, upconversion lasing based on two kinds of microcavity effects, Fabry–Pérot and whispering-gallery modes, from the microplates at room temperature is successfully achieved with a low threshold operating in multi- or single-mode, respectively. Surprisingly, the quality factor (

∼
3551

) is among the best values obtained from perovskite micro/nanoplate upconversion lasers without an external cavity. Moreover, the highly stable chromaticity with color drift only less than 0.1 nm also outbalances the all-inorganic

CsPbBr
3

ones. These superior performances of

CsPb
2

Br
5

microplate lasing with a facile solution synthesis procedure will offer a feasible structure to fabricate specific functionalities for high-performance frequency upconversion micro/nanoscale photonic integrated devices.
Learning words in a second language while cycling and listening to children’s songs: The Noplica Energy Center
Authors: Hahn Laura E. , ten Buuren Maaike , Snijders Tineke M. , Fikkert Paula
Published: July 2020

Children’s songs are a great source for linguistic learning. Here we explore whether children can acquire novel words in a second language by playing a game featuring children’s songs in a playhouse. The playhouse is designed by the Noplica foundation (www.noplica.nl) to advance language learning through unsupervised play. We present data from three experiments that serve to scientifically prove the functionality of one game of the playhouse: the Energy Center. For this game, children move three hand-bikes mounted on a panel within the playhouse. Once the children cycle, a song starts playing that is accompanied by musical instruments. In our experiments, children executed a picture selection task to evaluate whether they acquired new vocabulary from the songs presented during cycling. Two of our experiments were run in the field, one at a Dutch and one at an Indian preschool. The third experiment features data from a more controlled laboratory setting. Our results partly confirm that the Energy Center is a successful means to support vocabulary acquisition in a second language. More research with larger sample sizes and longer access to the Energy Center is needed to evaluate the overall functionality of the game. Based on informal observations at our test sites, however, we are certain that children do pick up linguistic content from the songs during play, as many of the children repeat words and phrases from the songs they heard. We will pick up upon these promising observations in future studies.
Chauffeuring parenthood: The everyday travel times of families
Authors: Schouten Maria Johanna , Heras Soledad Las
Published: July 2020

The time parents dedicate to the routine transport of their children has increased significantly since the second half of the twentieth century. This change was triggered by various developments, including new forms of parenthood, the central place the car has come to occupy in society and the tendency to urban dispersion. The article addresses the coordination efforts made by families to provide transport for their children to and from schools, nurseries or extracurricular activities. It focuses on the meaning parents attribute to the time spent on this transport, and on gender differences in this type of time allocation. To illustrate this point, analyses have been made of qualitative and quantitative data obtained in the context of a research on the use of time and technology in families, in the Portuguese districts of Castelo Branco and Braga, during the period 2010–12. The principal revelations of this research are the diversities but also general trends in representations and practices regarding temporalities and transport shown in interviews and focus group discussions. It was found that parents interviewed considered time devoted to routine transport of their children a care task; and, linked to this, mothers bore the brunt of this fragmented and time-consuming activity.
Social work, human rights and conceptions of human dignity: The case of social workers in Lisbon
Authors: Bittencourt Moema Bragança , Amaro Maria Inês
Published: July 2020

This article seeks to explore the conception of human dignity prevailing among social workers in Lisbon through a qualitative-type study. This departs from analysis of the concepts of humanity and the rule of law as guarantees for exercising social work in order to locate the concept of human dignity as a historical, social and cultural construct. The qualitative analysis of the data collected by interviews demonstrates that social workers, while not having a deep-reaching conceptual understanding of this theme, prioritize a Kantian conception of human dignity, perceiving this as an absolute value.
The correlations of the particle size, calorific value, moisture- and ash content of waste derived fuel, and examination of its heavy metal content
Authors: Leitol Csaba , Győrfi Alexandra , Kiss Tibor
Published: July 2020

Significant development has taken place in the field of waste management recently in the preparation of the energetic exploitation of recyclable, non-hazardous municipal solid waste. With mechanical-biological waste treatment, 35-40% of the weight of this waste can be made appropriate for energetic exploitation, mainly for co-incineration in cement factories and power plants.

The recoverability of waste derived fuel produced in mechanical-biological waste treatment plants highly depends on the burning and combustion technological properties of the mixture, and on its compounds influencing burning and different emissions. Waste recovery facilities do not take over fuel below a specific calorific value and over a given heavy metal, halogen and pollutant content.

In our research we were looking for correlations in the particle size, calorific value, moisture-, ash- and heavy metal content of waste derived fuel. On the basis of the measurement results, the connection between the particle size fractions and the fuel properties can clearly be stated. The fractions of smaller particle size have higher moisture-, ash- and heavy metal content, while the fractions of bigger particle size have higher calorific value.
Investigating the change of soil resistence and moisture content in the case of pre-crops and soil tillage systems
Authors: Tury Rita , Tóth Szilárd , Láposi Réka , Fodor László
Published: July 2020

The experiments were set up in large parcels at the Fleischmann Rudolf Research Institute of Eszterházy Károly University located in Kompolt. We carried out measurements by using a Penetronik penetrometer (electrical soil cone penetrometer) at the experimental site, where brown grassland soil as well as clay washed brown forest soil are the typical soil types. The device used primarily serves to investigate the physical and water management properties of soils suitable for agricultural cultivation. The instrument is a hand-operated tool for registering soil mechanical resistance in Newtons (0-1000 N) and also the moisture content of the topsoil (%) at the same time. The recording of the location of the measurement is made by the built-in GPS, and the results of the measurements are saved to the SD card of the device. The device’s data acquisition unit allows direct reading of measurement results, serial measurements and computer processing of results (0-70 cm). Taking our objectives into consideration, we defined the location of measuring points with various numbers according to the properties of the examined fields. Besides designating measuring points at a distance of 0, 5, 10, 15, 20 and 30 m from the edge of the fields, we designated two more in the middle of each field in all cases. The examined crop species included sand oats (Avena strigosa), baltacim (Onobrychis viciifolia) as well as common vetch (Vicia sativa L.) with oats as a companion crop. Summing up the measurement results, we have made the following statements: Low soil resistance (127-131 N) was experienced after soil loosening and oat-vetch with higher, well-preserved soil moisture content observed at each level, where the 50% moisture content of the soil started at the layer of 27 cm depth. Moderate soil resistance values (150-168 N) were manifested in the case of soil tillage with loosening and ploughing after sand oats. In this case, the 50 % soil moisture content was observed at the layer of 38 cm depth. Higher soil resistance values were found (171-196 N) in the case of 2 and 3-year-old crops of baltacim, respectively, where the 50 % soil moisture content was recorded from the layer of 58 cm depth. Based on the results, we consider it important to develop and improve soil tillage systems
Effects of solar panels on electrical networks
Authors: Bencs Peter , Al-Ktranee Mohammed , Mészáros Károly Marcell
Published: July 2020

Today, the increasing use of solar energy contributes to the EU's energy policies. Increasing use of renewable energy sources reduces pollutant emissions, dependence on fossil fuels and improves air quality. Globally, installed photovoltaic capacity has reached 400 GW by the end of 2017, and is projected to reach 4,500 GW by 2050. In the context of this research, we would like to present a detailed presentation of the possibilities and effects of integrating solar systems into electricity networks. The integration of renewable energies into networks is of paramount importance to researchers because of current energy demand and the depletion of fossil fuel reserves and environmental impacts. In this study, we highlight the effects of solar network integration on both the solar system and the public utility service. We also report on the opportunities and impacts of integration in Hungary in connection with our research. Today, solar panels are the cornerstone of sustainable development.
Additive manufacturing in the oil and gas industries
Authors: Omiyale Babatunde Olamide , Kayode Farayibi Peter
Published: July 2020

Additive manufacturing (AM), also known as 3D printing, is a process for creating prototypes and functional components achieved by consolidation of material layer upon layer. Applications of AM technologies have been witnessed in the healthcare, automotive, architecture, power generation, electronics and aviation industries. Some of the main benefits of AM include effective material utilisation, new design possibilities, improved functionality of the products and flexible production. The opportunities for the applications of additive manufacturing in the oil and gas industries are only just being explored. In this study, a review of the potential opportunities of AM technologies in oil and gas industries was reported. The adoption of the AM technologies necessitated the need for a rethink on design for manufacture and assembly of oil and gas component parts such as high-tech end burners, metal fuel nozzles, and submersible pump components amongst others. The possibility of employing AM technologies on-site for the production of spare parts for replacement of damage components in oil and gas equipment and facilities is commendable, as this brings about reduction in production downtime and replacement cost. The future of AM in the oil and gas industries is highly promising, however before AM can actualize its full-fledged potentials in these industries, further research is required in the area of new materials development and processing, improved surface finish of AM fabricated parts, enhanced fabrication speed and parametric optimisation to improve the mechanical properties of the fabricated components.