bluuebunny/crossref_metadata_2025 huggingface dataset:
Saliva Iodine Concentration in Children and Its Association with Iodine Status and Thyroid Function
Authors: Guo Wenxing , Pan Ziyun , Zhang Ying , Jin Ya , Dong Shuyao , Wu Wen , Chen Wen , Zhang Wanqi
Published: July 2020

Context

The effectiveness of saliva iodine concentration (SIC) in evaluating iodine status in children is not clear.

Objective

We aimed to explore associations between SIC and assessed indicators of iodine status and thyroid function.

Design

Cross-sectional study.

Setting

Primary schools in Shandong, China.

Participants

Local children aged 8 to 13 years with no known thyroid disease were recruited to this study.

Main outcome measures

Blood, saliva, and urine samples were collected to evaluate thyroid function and iodine status.

Results

SIC positively correlated with spot urinary iodine concentration (r = 0.29, P < 0.0001), 24-hour urinary iodine concentration (r = 0.35, P < 0.0001), and 24-hour urinary iodine excretion (r = 0.40, P < 0.0001). The prevalence of thyroid nodules (TN) and goiter showed an upward trend with SIC quantiles (P for trend < 0.05). Children with SIC <105 μg/L had a higher risk of insufficient iodine status (OR = 4.18; 95% CI, 2.67-6.56) compared with those with higher SIC. Those having SIC >273 μg/L were associated with greater risks of TN (OR = 2.70; 95% CI, 1.38-5.26) and excessive iodine status (OR = 18.56; 95% CI, 5.66-60.91) than those with lower SIC values.

Conclusions

There is a good correlation between SIC and urinary iodine concentrations. It is of significant reference value for the diagnosis of iodine deficiency with SIC of less than 105 μg/L and for the diagnosis of iodine excess and TN with SIC of more than 273 μg/L. Given the sanitary nature and convenience of saliva iodine collection, SIC is highly recommended as a good biomarker of recent iodine status in school-aged children.
Statin Use is Associated With Insulin Resistance in Participants of the Canadian Multicentre Osteoporosis Study
Authors: Rees-Milton Karen J , Norman Patrick , Babiolakis Corinne , Hulbert Maggie , Turner Mandy E , Berger Claudie , Anastassiades Tassos P , Hopman Wilma M , Adams Michael A , Powley Wendy L , Holden Rachel M
Published: July 2020

Context

Statins have been linked to the development of diabetes and atherosclerotic plaque calcification in patients with cardiac disease.

Objective

To determine the association between statin use and statin characteristics and insulin resistance and abdominal aortic calcification (AAC) in participants of the Canadian Multicentre Osteoporosis Study (CaMos).

Design

Observational study.

Setting

General community.

Participants

Nondiabetic participants of the Kingston CaMos site

Intervention

Insulin resistance and AAC in statin users and nonstatin users were compared with and without the inclusion of a propensity score (PS) to be on a statin. The covariates of hypertension, sex, body mass index, smoking, kidney stones, and age that were included in the PS were selected based on clinical judgment confirmed by the statistical analysis of a difference between statin users and nonstatin users.

Main Outcome Measures

Insulin resistance measured by the homeostasis model assessment (HOMA-IR) and AAC assessed on lateral spine radiographs using the Framingham methodology.

Results

Using a general linear model, statin use was associated with higher levels of HOMA-IR after stratified PS adjustment (β = 1.52, [1.18–1.95], P < 0.01). Hydrophilic statin users (n = 9) and lipophilic statins users (n = 30) had higher HOMA-IR compared to nonstatin users (n = 125) ([β = 2.29, (1.43–3.68), P < 0.001] and [β = 1.36, (1.04–1.78), P < 0.05]), respectively, in general linear models after stratified PS adjustment. Statin use was associated with AAC without stratifying by PS in the Wilcoxon test, but was no longer significant when stratified by PS.

Conclusions

Statins, widely prescribed drugs to lower cholesterol, may have unintended consequences related to glucose homeostasis that could be relevant in healthy aging.
Gendered Globality as a Cold War Framework
Authors: Chen Tina Mai
Published: July 2020

Originally penned by Mao Zedong in 1961 as an inscription on a photograph of female militia, “Bu ai hongzhuang, ai wuzhuang” 不爱红妆爱武 装 (“They love their battle array, not silks and satins”) for many sums up a presumed erasure of femininity in favor of a universalized masculine subject position within socialist China. This article reconsiders the discursive work done by militarized female bodies—physically and representationally—focusing on alternative international and internationalist futures following the Sino-Soviet split of 1960. The article critically engages state-to-state relations and internationally circulating PRC-produced cultural material that articulated feminist ideals as part of Afro-Asian-Latin American solidarity. This article returns to well-known texts of Maoist China to rethink state-produced Chinese feminism as a Cold War framework and gendered globality. It shifts the analytic from Cold War dichotomies that legitimate what most scholars misrepresent as an insular Chinese socialist female subjectivity of the 1960s to focus on the complex global dimensions of Cold War socialist feminism.
From Violated Girl to Revolutionary Woman
Authors: Kim Suzy
Published: July 2020

Feminism, both as theory and praxis, has long grappled with the dilemma of sex difference—whether to celebrate women’s “difference” from men as offering a more emancipatory potential or to challenge those differences as man-made in the process of delineating modern sexed subjects. While this debate may be familiar within contemporary feminist discourses, communist feminisms that stretched across the Cold War divide were no less conflicted about what to do with sex difference, most explicitly represented by sexual violence and biological motherhood. Even as communist states implemented top-down, often paternalistic measures, such policies were carried out ostensibly to elevate women’s status as a form of state feminism professing equality for the sexes. Comparing North Korea with China, this article explores how communist feminisms attempted to tackle the dilemma of sexual difference. Through an intertextual reading of two of the most popular revolutionary operas in 1970s communist East Asia—The Flower Girl from North Korea and The White-Haired Girl from China—it attends to the diverse strategies in addressing the “woman question” and the possibilities as well as limits opened up by communist feminisms.
Feminist Historical Writing in Postrevolutionary Iran
Authors: Ghandehari Alborz
Published: July 2020

This article argues that Mahmoud Dowlatabadi’s Missing Soluch and Parinoush Saniee’s My Share are landmark works of feminist historical writing in Iran that disrupt official narratives in the country regarding the revolutionary project. Despite the different positions Dowlatabadi and Saniee occupy in the Persian literary field, both Missing Soluch and My Share reflect the ethos of the 1979 Revolution in some way, one its euphoric beginning and the other its complicated aftermath. The article argues that both novelists pursue an innovative genre of historical writing by contesting official historical-masculinist narratives of their time. Missing Soluch offers readers a working-class feminist politics on the eve of revolutionary upheaval. My Share constructs a feminist politics critical of the postrevolutionary nation’s betrayal of Iranian women’s liberation despite women’s critical participation in the 1979 Revolution. Dowlatabadi anticipates the tensions between gender politics and the postrevolutionary nation, while Saniee makes that tension explicit as part of a feminist critique of historical erasure.
Simin Daneshvar and Shahrnush Parsipur in Translation
Authors: Beigi Leila Sadegh
Published: July 2020

Contemporary Iranian women writers contribute to the Iranian literary tradition by writing about women’s roles during the political upheavals leading up to and after the 1979 Revolution. In Simin Daneshvar’s Savushun and Shahrnush Parsipur’s Women without Men, the authors meticulously employ colloquial sexist diction to expose the connection between sexism and violence against women. The portrayal of such violence relies on language that illustrates the authors’ concerns and their commentary on the status of women. In this situation, literary criticism of the novels demands an approach that discusses feminism, language, and translation as interrelated. This article analyzes issues introduced in the translation of Savushun and Women without Men where translation choices have an impact on important elements of the original novels. By revealing how translation can minimize important culturally bound elements of Daneshvar’s and Parsipur’s feminist awareness and agency, it provides an example with relevance for critical translation studies.
Electrophysiologic and behavioral responses mediated by volatiles involved in the repellency of Apis mellifera (Lepeletier) (Hymenoptera: Apidae)
Authors: Pires Patricia Daniela da Silva , Sant'Ana Josué , Bisotto-de-Oliveira Ricardo
Published: July 2020

Repellent volatiles to insects might be an important tool for management of bees in areas which the presence of these organisms is not required. This study aimed to evaluate the electroantennal and behavioral responses of Africanized honeybees (workers), Apis mellifera (Lepeletier) (Hymenoptera Apidae), at different ages, to benzaldehyde (BA) and methyl anthranilate (MA) and to evaluate the potential repellency of these compounds under field conditions. Laboratory tests were conducted to study electroantennographic responses (mV) and chemotactic behavior of worker bees aged 1-5 (young) and 20-30 (old) days in four choice olfactometer. Electrophysiological responses to each compound did not differ between young and old workers. Bees antennae (young) triggered significantly greater responses to BA, in the older ones, a higher response was observed to MA, both compared to control (ethanol). The threshold response to BA and MA was achieved at 10 µg/µL, both compounds repelled bees at the same dose in olfactometer. Treatments with BA and MA, in field conditions, were less visited by scouter honey bees than those without these compounds (control).
Pooled Testing for SARS-CoV-2 in Hospitalized Patients
Authors: Mastrianni David , Falivena Richard , Brooks Timothy , McDermott Brian , Tan Josenia , Vandell Richard , Holland Michael
Published: July 2020

Viral testing for severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2), particularly early in the
COVID-19 pandemic, was limited by supply of reagents. We
pooled nasopharyngeal samples from patients at low risk
of SARS-CoV-2 infection in groups of 3 for testing. Three
weeks of testing using this strategy resulted in 530 patient
tests in 179 cartridges; 4 positive test groups required the
use of 11 additional cartridges with an overall positive rate
of 0.8% in a low-risk population. This strategy resulted
in the use of 340 fewer cartridges than if each test were
performed on one patient sample. Pooled testing of lowrisk
populations allows for continued testing even when
supplies are relatively scarce. Journal of Hospital Medicine
2020;15:538-539. © Society of Hospital Medicine
Improving Sports Media’s Crystal Ball for National Basketball Association Playoff Elimination
Authors: Husted Mark A. , Olinick Eli V. , Newman Alexandra M.
Published: July 2020

The National Basketball Association (NBA) is divided into two conferences, each of which comprises 15 teams. At the end of the regular season, the top eight teams from each conference, based on winning percentage, compete in the playoffs. Mixed-integer-programming (MIP) models determine when a team has guaranteed its position in the playoffs (clinched) or, conversely, when it has been eliminated before the completion of the regular season. Our models incorporate a series of complex two-way tiebreaking criteria used by the NBA to determine how many more games are needed either to clinch or to avoid elimination. We compare the time at which a given team has clinched or been eliminated, in terms of the number of games played in the season to date, as posted in the NBA official standings, against results from our mixed-integer program. For the 2017–2018 season, when our models outperform those of the NBA, they do so by an average of 4.1 games. We also describe a scenario in which the NBA erroneously reported that the Boston Celtics had clinched a playoff spot and, conversely, show that the Golden State Warriors had clinched a playoff spot before the official announcement by the NBA.
Discrete Element Modeling and Verification of an Outer Groove Wheel Fertilizer Applicator with Helical Teeth
Authors: Du Jun , Yang Quanjun , Xia Junfang , Li Ge
Published: July 2020

Highlights

An outer groove wheel fertilizer applicator with helical teeth was designed.

The helical teeth made the fertilizer mass and kinetic energy more stable.

The fertilizer mass rate was sensitive to the working length and rotational speed.

Abstract.
The fertilizer applicator plays an important role in making fertilization efficient, and a fertilizer applicator called the outer groove wheel fertilizer applicator (OGWFA) is widely used in the middle of China. An OGWFA with traditional straight teeth has a pulsation phenomenon and problems with breaks in application. To improve the fertilization performance, an OGWFA was designed with helical teeth in a staggered arrangement. The helical angle is an important parameter for the outer groove wheel (OGW), and 47.5° was considered a reasonable helical angle for this OGWFA according to fertilization performance simulated using discrete element modeling (DEM). The performances of OGWFAs with 47.5° helical teeth and with straight teeth were experimentally compared and analyzed by DEM. The OGWFA with helical teeth obtained lower coefficients of variation (CV) and break rates and smaller width of the fertilizer distribution. The simulation showed that the helical teeth made the fertilizer discharge more stable. The effects of working length, rotational speed, and coefficient of static friction between fertilizer particles on OGWFA performance were also simulated. Keywords: DEM, Discrete element method, Fertilizer applicator, Outer groove wheel.
Research Brief: Effect of Feed Form andFeeder Position on Feed Consumption Patterns in Male Broilers
Authors: Purswell Joseph L. , Kim Elizabeth J. , Branton Scott L.
Published: July 2020

Highlights

Male broilers showed significant preference for whole pellets as compared to a 50:50 (by mass) mixture of pellets and fines and 100% fines.

Broilers preferentially consumed pellets from the mixed diets, with 65% of the mixed diet consumed as pellets.

Changes in feeder location did not affect preferences, and locations of preferred feed forms were readily re-acquired after re-positioning.

Variation in pellet content may reduce effective feeder space through increased competition for pellets.

Abstract.
Post-starter phase broiler diets are almost universally pelleted during the manufacturing process to improve nutrient density, handling characteristics, and live performance. Low pellet durability, transportation, and on-farm handling and distribution can result in pellet destruction, ultimately resulting in variation in pellet distribution in a wire-auger feeding system. Given that poultry selectively feed to meet nutritional needs, the variation in pellet distribution observed in commercial feeding systems may result in a reduction in effective feeder space through increased competition for pellets. The objective of this study was to determine the effect of mixtures of feed form and location on feed consumption patterns in broilers. Feed form treatments included 100% pellets (P), a 50:50 mix (M) of pellets and fines (by mass), and 100% fines (F). A total of 264 broilers were randomly allocated to each of six rooms at 37 days of age and provided with each of the three feed form treatments in separate feeders. Feeder locations were rotated every three days, allowing each feed form treatment to be located in all three feeder positions. Overall mean consumption rates for each feed form treatment were significantly different (p = 0.0001) with 70.3%, 21.3%, and 8.1% for the pellet only, mixed, and fines diets, respectively, and a pooled SEM of 0.02%. No significant differences were found for feeder position (p = 0.12) or test period (p = 0.91). Broilers were able to reliably re-acquire the position of preferred feed form treatments after each location change Keywords: Feeding systems, Housing design, Poultry.
Challenges and Opportunities Associated with Drying Rough Rice in Fluidized Bed Dryers: A Review
Authors: Luthra Kaushik , Sadaka Sammy   S.
Published: July 2020

Highlights

Fluidized bed drying of rice has several advantages that outweigh its disadvantages.

Increasing the drying temperature above 60°C could reduce rice quality.

Research related to energy and exergy efficiencies in fluidized bed dryers of rice is needed.

Abstract.
Rice (Oryza sativa L.) is a staple food for more than half the world’s population. World rice production reached approximately 740 million metric tons (MMT) in 2018 due to the ever-increasing demand driven by population and economic growth. Rice producers face challenges in meeting this demand, especially in developing countries where rice is prone to spoilage if the moisture content is not reduced to a safe level shortly after harvest. Rice producers, particularly in developing countries, typically use conventional drying methods, i.e., sun drying and natural air drying. These methods are time-consuming and environmentally dependent. On the other hand, fluidized bed drying, which is a well established technology, could provide rice producers with an effective drying technique that is quick, practical, affordable, and portable. Several innovative designs for fluidized bed dryers have been developed that could be installed on-farm or off-farm at a reasonable cost. Some studies have mentioned that the main advantage of fluidized bed drying is the increase in drying rate and the reduction of rice spoilage after harvest. Conversely, other studies have raised alarms regarding low rice quality, which is seen as a significant flaw of fluidized bed drying. Due to this lack of consensus, there is a great need to review this drying technology objectively. Therefore, this review article explores fluidized bed drying and details its advantages and disadvantages related to rice drying. It also sheds light on the effects of the operating parameters involved in fluidized bed drying, i.e., rice moisture content, drying temperature, airflow rate, air velocity, drying duration, and tempering duration, on dryer performance and rice quality. Several fluidized bed numerical models are also reviewed and evaluated. Additionally, this review explores the energy and exergy efficiencies of fluidized bed dryers and suggests opportunities for research associated with fluidized bed drying of rice. Keywords: Energy, Exergy, Fluidized bed drying, Fluidized bed modeling, Moisture content, Rice quality, Rough rice, Tempering.
Agreement Between Visual and Model-Based Classification of Tomato Fruit Ripening
Authors: Kim Dong Sub , Lee Da Uhm , Lim Jeong Ho , Kim Steven , Choi Jeong Hee
Published: July 2020

Highlights

Human visual classification and predictive models often disagree when only color indices are used.

The degree of agreement is improved significantly when predictive models are cultivar-specific.

The degree of agreement can be improved when firmness and carotenoid contents are considered.

Abstract. Traditionally, the ripening stage of tomato fruit is determined by the observed percentage of red color on the fruit surface based on color charts provided by USDA standards. However, multiple observers can assign different ripening stages to the same tomato fruit due to subjectivity and/or inaccurate evaluations. This practical challenge has not been extensively discussed in the literature, so we assessed the degree of agreement between human visual classification and model-based prediction using physicochemical properties such as color (L*, a*, b*, hue, and chroma), firmness, and carotenoid contents. In our exploratory data analyses, we clearly observed increasing a* and decreasing L*, hue, and firmness with respect to ripening stage, but the rate of change seemed different from cultivar to cultivar. To assess the degree of agreement, cross-validations were used to compare thirty linear regression models with various combinations of the predictors. The cross-validations indicated that predictions from a cultivar-specific model agreed well with human visual classifications. When the cultivar-specific model was considered with the color indices, we achieved up to 95.5% accuracy. When firmness, lycopene, and ß-carotene were added to the model, the accuracy increased to 96.8%. These results suggest the reliability of non-destructive methods for auto-sorting systems. Keywords: ß-carotene, Color index, Firmness, Fruit color, Lycopene, Ripening, Tomato.
Deep-learning-based binary hologram
Authors: Goi Hiroaki , Komuro Koshi , Nomura Takanori
Published: July 2020

Binary hologram generation based on deep learning is proposed. The proposed method can reduce the severe effect of quality degradation from binarizing gray-scaled holograms by optimizing the neural network to output binary amplitude holograms directly. In previous work on binary holograms, the calculation time for generating binary holograms was long. However, in the proposed method, once the neural network is trained enough, the neural network generates binary holograms much faster than previous work with comparable quality. The proposed method is more suitable for opportunities to generate several binary holograms under the same condition. The feasibility of the proposed method was confirmed experimentally.
Measurement error estimation and calibration for on-line detection phase variations in the laser-induced damage growth features of optical components
Authors: Li Jie , Ba Rongsheng , Zhou Xinda , Zheng Yinbo , Ding Lei , Huang Yuan , Chai Liqun , Ren Huan , Tang Xiaodong
Published: July 2020

The amplitude and phase distributions of reflection or transmission light are locally disturbed by damage regions. The damage state of optical components under successive laser irradiation can be evaluated according to the phase variation of a transmitted beam. The measurement accuracy of phase information related to the phase-unwrapping method is a critical factor for evaluating the damage state. This study analyzes and compares the performance of two important phase-unwrapping methods for detecting on-line large damage sites based on optimal modified lateral shearing interferometry. Meanwhile, the system stability and the measurement repeatability are also validated according to the retrieved phase pattern, which is beneficial to estimating the measurement accuracy. Experimental results of optical films are also presented and discussed to verify the feasibility of the estimation method utilized and the recommended phase-unwrapping method for on-line detection of the laser-induced damage growth features.
Time-delay signature suppression of polarization-resolved wideband chaos in VCSELs with dual-path chaotic optical injections
Authors: Chen Jianjun , Li Chenxu , Mu Xueli , Li Linfu , Duan Yingni
Published: July 2020

The combining investigation on the time-delay signature (TDS) and chaos bandwidth have been theoretically investigated in a vertical-cavity surface-emitting laser (VCSEL) system with dual-path chaotic optical injections. In this scheme, the polarized chaos with the TDS from an external-cavity master VCSEL is routed into two different paths and then unidirectionally injected into another solitary slave VCSEL. With the aid of the autocorrelation function and the effective bandwidth calculation, the TDS and bandwidth of polarized chaos from the chaotic system are quantitatively evaluated. The results show that, in such a dual-path chaotic optical-injection system, the high-quality polarized chaos with the successful TDS suppression and chaotic bandwidth enhancement can be achieved in wider parameter regions in contrast with the case for the single-path chaotic optical injection. Further research also finds that the injected time-delay difference between two injection paths is desired to mismatch the feedback time delay, which is conducive to suppressing TDS and expanding bandwidth of polarized chaos. Besides, the better chaotic quality with low TDS and wide bandwidth can be expected by choosing the appropriate injection strengths of two injection paths.
Optimizing infrared spectral discrimination to enhance disease diagnostics: monitoring the signatures of inflammatory bowel diseases with anti-TNFα therapy
Authors: Ghimire Hemendra , Hu Xinjie , Qin Gengsheng , Unil Perera A. G.
Published: July 2020

This study presents an application of infrared spectroscopy of sera for monitoring the efficacy of anti-TNFα therapy for inflammatory bowel diseases. Understanding the therapeutic response includes the analysis of absorption bands representing constituent molecules. Interleukin-10 knockout mouse model of the diseases with anti-TNFα treatment was used. The discrimination potential is optimized by analyzing data with curve fitting. It shows; antibody therapy markedly ameliorated the disease, concurring with earlier mucosal immunology and pathophysiologic studies. This technique may thus also be useful for the evaluation of mucosal healing or other therapeutic modalities of gastrointestinal tract diseases keeping the endoscopic tests as confirmatory.
Unidirectional ultrabroadband and wide-angle absorption in graphene-embedded photonic crystals with the cascading structure comprising the Octonacci sequence
Authors: Guo Sijia , Hu Caixing , Zhang Haifeng
Published: July 2020

Using the transfer matrix method, a unidirectional absorber with an ultrabroadband absorption bandwidth and angular stability is realized in the graphene-embedded photonic crystals (GPCs) arranged by the cascading structure formed with the periodic sequence and the quasi-periodic Octonacci sequence in the terahertz regime. As a result, the surface conductivity of the graphene sheet can be modulated via the chemical potential, and the characteristics of the proposed absorber are tunable. Compared to the structure spliced by the diverse periodic sequences, the relative absorption bandwidth of the proposed composite construction is up to 94.53%, which far outweighs that of the periodic one. We compare the Octonacci sequence, the Fibonacci sequence, and the Thue–Morse sequence, and the calculated results reveal the advantage of the Octonacci sequence in the expansion of the absorption bandwidth. Under the optimization of the related parameters, the incident wave is primarily reflected in the forward propagation and absorbed in a wide range of

θ

under the TM mode in backward propagation, which shows the splendid unidirectionality and angular stability. The impacts of the chemical potential, structural thicknesses, and stack numbers on the absorption properties are also investigated in detail. Additionally, the impedance match theory and the interference field theory are introduced to explain the intrinsic absorption mechanism of the presented GPCs. In short, the unidirectional broadband and angle-insensitive absorber has extensive application prospects in optical sensing, optical filtering, photodetection, and solar energy collection.
Gaussian basis expansion phase noise suppression method for CO-OFDM systems
Authors: Huang Yongtao , Chen Yuanxiang , Li Kaile , Han Ying , Fu Jia , Ma Jie , Li Yitong , Yu Jianguo , Li Xinguo
Published: July 2020

In this paper, we propose a novel phase noise suppression method based on Gaussian basis expansion (GBE) for CO-OFDM systems. We analyze the basic phase noise suppression principle of GBE and then demonstrate it in optical OFDM transmission systems. Compared with common phase compensation (CPE), orthogonal basis expansion (OBE) and eigenvector basis expansion (EBE) schemes, the proposed GBE scheme has better phase noise fitting ability with similar computation complexity. Futhermore, no additional back to back (BTB) pre-training is needed for the GBE scheme. Performance improvements by the GBE is experimental validated in the QPSK/16-QAM OFDM system with different transmission scenarios (different number of pilots and input power). In the QPSK-OFDM system, after 160 km SSMF transmission, a Q-factor improvement of 1.7 dB and 0.5 dB are achieved compared with the CPE and OBE schemes at the optimum input power of -4 dBm, respectively. In the 16-QAM-OFDM system, the measured BER improved from 8.21×10−4 to 2.36×10−4 with the GBE scheme. To further verify the effectiveness of the GBE scheme, we change the laser linewidth and measure the long transmission distance performance by simulation, the results show that the GBE scheme can effectively increase the laser linewidth tolerance and extend transmission distance. When the linewidth is 2-MHz, the proposed GBE scheme can extend the transmission distance from 1120 km to 1540 km at the BER of 10−4. Experimental and simulation results show that the proposed GBE scheme is a promising alternative phase noise suppression for CO-OFDM system.
Integrated microwave acousto-optic frequency shifter on thin-film lithium niobate
Authors: Shao Linbo , Sinclair Neil , Leatham James , Hu Yaowen , Yu Mengjie , Turpin Terry , Crowe Devon , Lončar Marko
Published: July 2020

Electrically driven acousto-optic devices that provide beam deflection and optical frequency shifting have broad applications from pulse synthesis to heterodyne detection. Commercially available acousto-optic modulators are based on bulk materials and consume Watts of radio frequency power. Here, we demonstrate an integrated 3-GHz acousto-optic frequency shifter on thin-film lithium niobate, featuring a carrier suppression over 30 dB. Further, we demonstrate a gigahertz-spaced optical frequency comb featuring more than 200 lines over a 0.6-THz optical bandwidth by recirculating the light in an active frequency shifting loop. Our integrated acousto-optic platform leads to the development of on-chip optical routing, isolation, and microwave signal processing.
High-fidelity heralded quantum squeezing gate based on entanglement
Authors: Liu Kui , Li Jiaming , Yang Rongguo , Zhai Shuqin
Published: July 2020

Squeezing operation is critical in Gaussian quantum information. A high-fidelity heralded squeezing gate was recently realized using a noiseless linear amplifier with moderate ancillary squeezing. Here we analyze the heralded scheme based on squeezing [J. Zhao, Nat. Photonics, 14, 306 (2020)] and find that its fidelity depends heavily on the purity of auxiliary squeezing, and even the fidelity with a 6 dB pure squeezed state is better than with a 15 dB thermal squeezed state. On this basis, we construct a new heralded squeezing gate based on teleportation, which can overcome the shortcomings of the heralded scheme based on squeezing and is immune to the purity of input squeezing. It can better use the current best available squeezing (15 dB) to realize a perfect squeezing gate for fault-tolerant continuous-variable quantum computation. This scheme is promising to realize other single-mode Gaussian operations and non-classical state squeezing operations.
Meta-atom library generation via an efficient multi-objective shape optimization method
Authors: Whiting Eric B. , Campbell Sawyer D. , Kang Lei , Werner Douglas H.
Published: July 2020

Optimizing the shape of metasurface unit cells can lead to tremendous performance gains in several critically important areas. This paper presents a method of generating and optimizing freeform shapes to improve efficiency and achieve multiple metasurface functionalities (e.g., different polarization responses). The designs are generated using a three-dimensional surface contour method, which can produce an extensive range of nearly arbitrary shapes using only a few variables. Unlike gradient-based topology optimization, the proposed method is compatible with existing global optimization techniques that have been shown to significantly outperform local optimization algorithms, especially in complex and multimodal design spaces.
Ultralow noise DFB fiber laser with self-feedback mechanics utilizing the inherent photothermal effect
Authors: Ying Kang , Liang Hong , Chen Dijun , Sun Yanguang , Pi HaoYang , Wei Fang , Yang Fei , Cai Haiwen
Published: July 2020

Single frequency laser sources with low frequency noise are now at the heart of precision high-end science, from the most precise optical atomic clocks to gravitational-wave detection, thanks to the rapid development of laser frequency stabilization techniques based on optical or electrical feedback from an external reference cavity. Despite the tremendous progress, these laser systems are relatively high in terms of complexity and cost, essentially suitable for the laboratory environment. Nevertheless, more and more commercial applications also demand laser sources with low noise to upgrade their performance, such as fiber optic sensing and LiDAR, which require reduced complexity and good robustness to environmental perturbations. Here, we describe an ultralow noise DFB fiber laser with self-feedback mechanics that utilizes the inherent photothermal effect through the regulation of the thermal expansion coefficient of laser cavity. Over 20 dB of frequency noise reduction below several tens of kilohertz Fourier frequency is achieved, limited by the fundamental thermal noise, which is, to date, one of the best results for a free-running DFB fiber laser. The outcome of this work offers promising prospects for versatile applications due to its ultralow frequency noise, simplicity, low cost, and environmental robustness.
Quantum erasing of laser emission in N2+
Authors: Danylo Rostyslav , Lambert Guillaume , Liu Yi , Tikhonchuk Vladimir , Houard Aurélien , Mysyrowicz André
Published: July 2020

Cavity-free lasing of

N

2
+

induced by a femtosecond laser pulse at 800 nm is nearly totally suppressed by a delayed twin control pulse. We explain this surprising effect within the V-scheme of lasing without population inversion. A fast transfer of population between nitrogen ionic states

X

2

Σ
g
+

and

A

2

Π
u

, induced by the second pulse, terminates the conditions for amplification in the system. The appearance of short lasing bursts at delays corresponding to revivals of rotational wave packets is explained along the same lines.
Label-free lipid contrast imaging using non-contact near-infrared photoacoustic remote sensing microscopy
Authors: Kedarisetti Pradyumna , Haven Nathaniel J. M. , Restall Brendon S. , Martell Matthew T. , Zemp Roger J.
Published: July 2020

Histopathology of lipid-rich tissues is often a difficult endeavor, owing to the limited tissue processing workflows that can appropriately preserve tissue while keeping fatty deposits intact. Here, we present the first usage of near-infrared (NIR) photoacoustic remote sensing (PARS) to achieve imaging contrast from lipids without the need for exogenous stains or labels. In our system, the facile production of 1225 nm excitation pulses is achieved by the stimulated Raman scattering of a 1064 nm source propagating through an optical fiber. PARS-based detection is achieved by monitoring the change in the scattering profile of a co-aligned 1550 nm continuous-wave interrogation beam in response to absorption of the 1225 nm light by lipids. Our non-contact, reflection-mode approach can achieve a FWHM resolution of up to 0.96 µm and signal-to-noise ratios as high as 45 dB from carbon fibers and 9.7 dB from a lipid phantom. NIR-PARS offers a promising approach to image lipid-rich samples with a simplified workflow.
Reconstruction method of a ptychographic dataset with unknown positions
Authors: Xu Wenhui , Lin Huixiang , Wang Hangyu , Zhang Fucai
Published: July 2020

Wavefield drift or wobbling occurs quite often in coherent scanning systems such as satellite laser communication, laser pointing of high-power lasers, or microscopy. The uncertainty of wavefront positions might result in blurred images or large measurement errors. Here we propose an iterative approach that can retrieve both the drift positions and complex-valued distribution of the wavefield from a ptychographic diffraction intensity dataset. We demonstrate the feasibility and effectiveness of the method in numerical simulation and an optical experiment. The method requires little a priori knowledge and thus would open up new opportunities in many fields.
High-power structured laser modes: manifestation of quantum Green’s function
Authors: Chen Y. F. , Tseng Y. C. , Ke H. T. , Hsieh M. X. , Tung J. C. , Hsieh Y. H. , Liang H. C. , Huang K. F.
Published: July 2020

The distributions of resonant frequencies in an astigmatic cavity are theoretically confirmed to be analogously equivalent to the quantum energy structures of two-dimensional commensurate harmonic oscillators. In the first part [Opt. Lett. 45, 4096 (2020)OPLEDP0146-959210.1364/OL.399251] of this two-part series study, the lasing modes were verified to reveal a variety of vortex array structures. Here, in the second part of this two-part series study, the lasing modes are confirmed to agree very well with the quantum Green’s functions that correspond to a bundle of Lissajous figures in the high-order regime.
50-µJ level, 20-picosecond, narrowband difference-frequency generation at 4.6, 5.4, 7.5, 9.2, and 10.8 µm in LiGaS2 and LiGaSe2 at Nd:YAG laser pumping and various crystalline Raman laser seedings
Authors: Smetanin S. N. , Jelínek M. , Kubeček V. , Kurus A. F. , Vedenyapin V. N. , Lobanov S. I. , Isaenko L. I.
Published: July 2020

A comparative study of picosecond mid-IR difference frequency generation in a wide wavelength range of 4.6-10.8 µm in a simple down-converter based on the 8-mm long, high-damage-threshold crystals of LiGaS2 or LiGaSe2 under the 5-mJ, 20-ps, 1.064-µm Nd:YAG laser pumping and the single-pass crystalline (CaCO3, BaWO4, CVD-diamond) Raman laser seeding was presented. 10-µJ-level, narrowband (<2 cm−1) generation at discrete wavelengths of 4.6, 5.4, 7.5, and 9.2 µm with the optical frequencies equal to the vibrational Raman frequency or its second harmonic of various crystalline Raman seeders was demonstrated. Optimization of the pump spot and mode-matching between the pump and signal spots allowed to increase the output pulse energy up to 50 µJ in the case of LiGaSe2.
Classroom-Based Mindfulness Training Reduces Anxiety in Adolescents: Acceptability and Effectiveness of a Cluster-Randomized Pilot Study
Authors: Johnstone Jeanette M. , Ribbers Amanda , Jenkins David , Atchley Rachel , Gustafsson Hanna , Nigg Joel T. , Wahbeh Helané , Oken Barry
Published: July 2020

Objective: Many high school students experience a high degree of anxiety and perceived stress. This study examined whether a classroom-based mindfulness program or a wellness program were acceptable and effective as anxiety and stress reduction interventions based on students’ self-reports.

Design, setting, and participants: Thirteen health education classes (n=285 students, aged 14–16 years) were randomized by classroom to one of three conditions: mindfulness, wellness, or usual health class only (passive control/waitlist), for 8 weeks.

Outcomes: Pre- and post-intervention scores compared self-reported measures of depression, anxiety and stress.

Results: Complete data were available from nine classes (n=202 students). Post-intervention anxiety scores were reduced in students who received the mindfulness intervention compared to those who received only their usual health class (β=−0.07, SE=0.03, P≤0.001; 95% CI=−0.12, −0.02). No significant between group differences were found for depression or stress (P>0.4). Students’ satisfaction with the mindfulness intervention they received withstood baseline credibility and expectancy effects: r=0.21, n=67, P=0.17 for credibility; r=−0.001, n=67, P=0.99 for expectancy. However, students’ satisfaction with the wellness intervention they received was positively correlated with their pre-intervention expectations, r=0.42, n=47, P<0.001. Fifty-two percent of the 68 students assigned to mindfulness (n=35) used the iPad app for mindfulness home practice at least once; of those, 10% used it 10 or more times.

Conclusion: Eight weeks of classroom-based mindfulness, with limited home practice, reduced self-reported anxiety compared to usual health class, and withstood baseline expectancy effects in this group of high school students, a majority who come from high income families.

Clinical implications: School- or community-based mindfulness may be an appropriate recommendation for adolescents who experience anxiety.
Artificial intelligence in schools: Towards a democratic future
Authors: Leaton Gray Sandra
Published: July 2020

The introduction of artificial intelligence in education (AIED) is likely to have a profound impact on the lives of children and young people. This article explores the different types of artificial intelligence (AI) systems in common use in education, their social context and their relationship with the growth of commercial knowledge monopolies. This in turn is used to highlight data privacy rights issues for children and young people, as defined by the 2018 General Data Protection Regulations (GDPR). The article concludes that achieving a balance between fairness, individual pedagogic rights (Bernstein, 2000), data privacy rights and effective use of data is a difficult challenge, and one not easily supported by current regulation. The article proposes an alternative, more democratically aware basis for artificial intelligence use in schools.
New digital laboratories of experimental knowledge production: Artificial intelligence and education research
Authors: Williamson Ben
Published: July 2020

Education data scientists, learning engineers and precision education specialists are new experts in knowledge production in educational research. By bringing together data science methodologies and advanced artificial intelligence (AI) systems with disciplinary expertise from the psychological, biological and brain sciences, they are building a new field of AI-based learning science. This article presents an examination of how education research is being remade as an experimental data-intensive science. AI is combining with learning science in new ‘digital laboratories’ where ownership over data, and power and authority over educational knowledge production, are being redistributed to research assemblages of computational machines and scientific expertise.
Education in an uncertain future: Two scenarios
Authors: White John
Published: July 2020

This article examines two scenarios for the future of education over the coming decades, mainly in England but also in comparable countries. It does so against the background of six large-scale historical processes now in progress: increasing longevity, the expansion of the internet, changes in work patterns, climate change, the rise in inequality and the coming of populism. Scenario 1 continues current patterns in general politics and education, while Scenario 2 radically diverges from them. Over half the article is devoted to the future of education in Scenario 2.
Lugares de Memória
Authors: Zanetti Valéria , Silva Maria Helena Alves da , Papali Maria Aparecida Chaves Ribeiro , Prince Ana Enedi Silva
Published: July 2020

Este artigo, de caráter descritivo reflexivo, busca, por meio de relatos da criação de três centros de memória e documentação histórica apoiados pela Universidade do Vale do Paraíba (Univap), apresentar a difícil tarefa de convencimento dos profissionais da História dessa universidade junto à comunidade, de que a preservação da memória passa pelo valor que se atribui ao passado e que as iniciativas de preservação do patrimônio documental são marcadas pela estreita relação entre a experiência e a consciência social.
Tambores da Resistência
Authors: Figueiredo Lowande Walter Francisco , Bueno Camila Silva
Published: July 2020

Argumentamos que a ideia de “patrimônio cultural” está diretamente atrelada à consolidação das sociedades modernas, funcionando como um dispositivo fundamental para a cisão ontológica entre humanidade e natureza que caracteriza a modernidade. Considerando que esta cosmovisão nos conduziu à catastrófica época geológica do Antropoceno, propomos a adoção de um dispositivo substituto, o “patrimônio cosmológico”, que nos permita aprender com visões de mundo e experiências do tempo extramodernas sobre como compor coletivos de humanos e não-humanos a fim de resistirmos ao caráter destrutivo da modernidade. Por fim, descrevemos algumas das práticas do grupo percussivo Maracatu Muiraquitã, da cidade de Alfenas, MG, com o objetivo de demonstrar como é possível construir aprendizados significativos, por meio da observação experimental de composições cosmopolíticas extramodernas, que nos permitam construir futuros alternativos à reprodução do sistema produtivo moderno/ocidental/capitalista.

Palavras-chave: Patrimônio cosmológico. Maracatu de Baque Virado. Antropoceno.
O Museu da Cidade de Governador Valadares
Authors: Pereira da Silva Lucinei , Lana Mara de Castro Siman
Published: July 2020

Este artigo propõe uma reflexão sobre a narrativa que emerge da exposição encenada pelo Museu da Cidade de Governador Valadares/MG. Tentaremos compreender também como ele se apresenta e se organiza e se esta instituição busca trazer uma memória e história de GV de forma homogênea ou tenta apresentar através de seu acervo toda a complexidade existente nessa cidade. O Museu da Cidade de Governador Valadares foi fundado em 30 de janeiro de 1983 e reúne coleções de arqueologia, objetos de diferentes ofícios e meios de transporte, moedas, instrumentos musicais, mobílias e fotografias antigas da cidade. Em nossa análise, observamos que as escolhas expográficas nesta instituição parecem atender ao objetivo de reforçar o mito dos desbravadores que enfrentaram o sertão inóspito e lutaram pela emancipação da cidade. Na verdade, a figura dos chamados "pioneiros", que se consolida como mito fundador/emancipador, está vinculada, primeiramente, à epopeia dos primeiros habitantes da cidade e até hoje considerados como distintos e notáveis moradores.
Corpos, violências, silenciamentos
Authors: Cavalcante André
Published: July 2020

Pensando as condições de produção do discurso, o imaginário do/sobre os sujeitos trans e o marco temporal das eleições de 2018, objetivamos analisar a relação entre os silenciamentos e a resistência do/sobre o corpo trans no espaço virtual. Para tanto, elencamos duas matérias postadas em meios digitais, uma sobre a peça “O Evangelho segundo Jesus, Rainha do Céu”, quando houve sua interdição no Festival de Inverno de Garanhuns (PE) e outra sobre um assassinato de uma travesti em São Paulo (SP), com vistas a compreendermos as disputas de sentidos sobre as corporeidades trans através da fundamentação teórica da Análise do Discurso materialista. Juntamente com as matérias, analisaremos seus comentários, uma vez que este é um espaço no qual, pela ilusão de tudo se poder dizer, os sujeitos produzem discursos em consonância com a causa trans ou discursos de ódio que deslegitimam, silenciam e deslocam sentidos sobre estes corpos.