bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical Study on TiOOH Production over Au/TiO2 Catalyst —Support Dependency of Propylene Oxide Production—
Authors: Hamada Yasutaka , Mishima Yuki , Yonemori Tomohisa , Kawakami Takashi , Yamanaka Shusuke , Okumura Mitsutaka
Published: October 2023

Au supported anatase TiO2 enables the selective synthesis of propylene oxide from propylene using O2 and H2. However, this reaction does not proceed on Au supported rutile TiO2. The origin of this difference in the catalytic activity was examined using DFT calculations. DFT calculations revealed that the stability of the TiOOH active species was directly related to the product selectivity.
Ischiofemoral Impingement Due to an Undiagnosed Pelvic Avulsion Fracture
Authors: Warren Alec T. , Ahmed Abubakar , Raja Altamash E.
Published: October 2023

Ischial tuberosity (IT) avulsion fractures are an uncommon cause of injuries in athletes. In this case, a 26-year-old female suffering from posterior right hip pain for over a decade presented with debility and a decrease in athletic function. Notable history included a hamstring strain while sprinting in elementary school. Clinical examination suggested hamstring tendinopathy and ischiofemoral impingement (IFI). Magnetic resonance imaging (MRI) revealed a chronic, fragmented, IT apophyseal avulsion fracture with ischial bursitis and edema within the fragmented bone, suggesting the development of heterotopic ossification (HO). Diagnostic ultrasound revealed signs of IFI, not evident on MRI. Ultrasound-guided corticosteroid injection in her ischial bursa and ischiofemoral space provided complete relief. The patient was able to resume her activities of daily living and sports-related activities without pain. Although interventional treatments may provide temporary pain relief, a multimodal approach is required for the treatment of HO.
Decolonizing ELT teacher education by incorporating knowledge of local communities in the teaching practicum
Authors: Quintero Luz Mary , Olarte Clavijo Amparo
Published: October 2023

Despite significant advances in the epistemological frameworks that guide teacher education in Colombia and elsewhere, it continues to be governed mostly by traditional Eurocentric paradigms. Decolonizing teacher education requires epistemological moves to resignify the plurality of local knowledges and praxis. This article aims at reporting a qualitative research project carried out with three student teachers of a teacher education program with emphasis on English, at a public university in the northeast of Colombia. The main objective was to explore and reflect on how EFL pre-service teachers incorporated knowledge of local communities as resources for language teaching and learning during the practicum. Data were gathered over a three-semester period through pre-service teachers’ lesson plans, materials, a final academic report, and a semi-structured interview. Data were analyzed based on the principles of thematic data analysis. Findings revealed that student teachers approached knowledge from an ecological perspective coming from different ways of knowing, seeing, being and living in the world. At the same time, the ecology of knowledges helped them to overcome the challenges they faced during the project.
Diversity, Informant Consensus Factor and Cultural Significance Index of Wild Edible Plants in the Jaunpur region, Tehri Garhwal, Uttarakhand
Authors: Dangwal Lakhi Ram , Lal Tarseem
Published: October 2023

The wild edibles are essential not only for nutrition, medicine, fodder and fuel but also as potential source of income generation. The conventional use of wild edible plants is habitual in the remote and hill regions of the Uttarakhand state (India). The present study was carried out in a mountainous part of the Uttarakhand namely Jaunpur region situated in the district Tehri Garhwal. Extensive field surveys were conducted in the area to gather information (traditional knowledge on wild edible plants) from the inhabitants through questionnaire method. A total of 220 key informants including old aged farmers, shepherds, and vaidyas were surveyed. The present study resulted in documentation of a total 73 plant species (under 58 genera and 38 families) as source of wild edibles. Rosaceae (10 species) and Fabaceae (7 species) revealed as the most dominant families followed by Anacardiaceae, Moraceae and Rutaceae (4 species each). Majority of the recorded species belong to the tree habit (35% species) followed by herb (29%), shrub (29%), and climber (7%). The commonly used plant parts as source of wild edible in the area include fruits (59% species), leaves (24%), seeds (5%) and flowers (4%). Documentation of the traditional knowledge is much important because it provide alternative means to reduce hunger, poverty, and health issues especially in finding novel compounds (drug discovery).
¿Existió una Escuela de Salamanca en asuntos económicos?/Was there a Salamanca School on economic issues?
Authors: Perdices de Blas Luis , Ramos Gorostiza José Luis
Published: October 2023

La utilización de la denominación “Escuela de Salamanca” en referencia a los aspectos económicos es confusa y problemática, porque no hay argumentos convincentes para sostener que fuera una auténtica escuela de pensamiento económico (tal como la definen Schumpeter y Stigler). Sin embargo, desde Larraz y Grice-Hutchinson, los historiadores del pensamiento económico han utilizado habitualmente dicha denominación por su poder como “marca comercial” para la divulgación, y también para hacer referencia de forma breve y sencilla a las notables aportaciones analíticas de un conjunto de doctores escolásticos españoles. De hecho, las monografías de los historiadores se han concentrado sobre todo en analizar las contribuciones de estos escolásticos (teoría monetaria, derechos de propiedad, etc.), más que en discutir los criterios que podrían definirles como una escuela en asuntos económicos.
Caracterización de la inversión española en la República de Ecuador durante el segundo periodo de Alianza País (2013-2017). Análisis de los inversores españoles entre 2013-2017/Characterisation of Spanish investment in the Republic of Ecuador during the second period of Alianza País (2013-2017)
Authors: Fernández García Carlos , Pérez Rico Cristina
Published: October 2023

El propósito de esta investigación es caracterizar la inversión española en Ecuador, y analizar las percepciones sobre ésta de las empresas ibéricas que desarrollan su actividad en esta república Latinoamericana. Esta información es de especial relevancia para las instituciones gubernamentales, y para los potenciales inversores. Para realizar el trabajo se utilizó una metodología cualitativa con una perspectiva socioeconómica de tipo exploratoria de bola de nieve. Los resultados muestran como principal conclusión que los diez años del gobierno del presidente Rafael Correa han sido positivos para la inversión en términos generales debido a la continuidad del gobierno que influyó en una mayor estabilidad política y social, que dio lugar a un periodo de crecimiento económico por encima de muchos países desarrollados. En relación a las multinacionales españolas, también fue favorable, por su participación en grandes proyectos de obra civil que supusieron importantes ingresos en una época de recesión económica y reducida inversión en España.
Ensemble Experiments to Optimize Interventions Along the Customer Journey: A Reinforcement Learning Approach
Authors: Song Yicheng , Sun Tianshu
Published: October 2023

Firms adopt randomized experiments to evaluate various interventions (e.g., website design, creative content, and pricing). However, most randomized experiments are designed to identify the impact of one specific intervention. The literature on randomized experiments lacks a holistic approach to optimize a sequence of interventions along the customer journey. Specifically, locally optimal interventions unveiled by randomized experiments might be globally suboptimal when considering their interdependence as well as the long-term rewards. Fortunately, the accumulation of a large number of historical experiments creates exogenous interventions at different stages along the customer journey and provides a new opportunity. This study integrates multiple experiments within the reinforcement learning (RL) framework to tackle the questions that cannot be answered by stand-alone randomized experiments. How can we learn optimal policy with a sequence of interventions along the customer journey based on an ensemble of historical experiments? Additionally, how can we learn from multiple historical experiments to guide future intervention trials? We propose a Bayesian recurrent Q-network model that leverages the exogenous interventions from multiple experiments to learn their effectiveness at different stages of the customer journey and optimize them for long-term rewards. Beyond optimization within the existing interventions, the Bayesian model also estimates the distribution of rewards, which can guide subject allocation in the design of future experiments to optimally balance exploration and exploitation. In summary, the proposed model creates a two-way complementarity between RL and randomized experiments, and thus, it provides a holistic approach to learning and optimizing interventions along the customer journey.

This paper was accepted by Anindya Ghose, information systems.

Funding: This work was supported by Adobe Faculty Research Award and the Marketing Science Institute Research Grant.

Supplemental Material: The data files and online appendix are available at https://doi.org/10.1287/mnsc.2023.4914 .
Cattle fetal sex determination using cell-free fetal DNA from maternal blood in the Mekong Delta, Vietnam
Authors:   Institute of Food and Biotechnology, Can Tho University, Can Tho 900000, Vietnam, Tran Thi Thanh Khuong , Nguyen Dang Khoa ,   Institute of Food and Biotechnology, Can Tho University, Can Tho 900000, Vietnam,   Department of Life Science in Dentistry, School of Dentistry, Pusan National University, Yangsan 50612, Republic of Korea, Nguyen Van Loi ,   Institute of Food and Biotechnology, Can Tho University, Can Tho 900000, Vietnam, Tran Van Be Nam ,   Institute of Food and Biotechnology, Can Tho University, Can Tho 900000, Vietnam, Tran Gia Huy ,   Institute of Food and Biotechnology, Can Tho University, Can Tho 900000, Vietnam, Nguyen Trong Ngu ,   Department of Animal Sciences, College of Agriculture, Can Tho University, Can Tho 900000, Vietnam, Lam Phuoc Thanh ,   Department of Animal Sciences, College of Agriculture, Can Tho University, Can Tho 900000, Vietnam, Cao Thi Tai Nguyen ,   Biology Genetics Department, Faculty of Basic Science, Can Tho University of Medicine and Pharmacy, Can Tho 900000, Vietnam
Published: October 2023

Cell-free fetal DNA (cffDNA) from fetal calves was isolated in the bovine maternal plasma in the fifth week of pregnancy, accounting for around 10% of the total. Recently, cffDNA has been used as a non-invasive prenatal screening technique for aneuploidy, genetic disorders in humans, early pregnancy diagnosis, and animal fetal sex determination. This study's objective was to identify the presence of cffDNA in the blood of 13 dairy cows (11 pregnant, 2 non-pregnant, and 1 unmarred) gathered from farms in Can Tho, the Mekong Delta, Vietnam. Plasma / Serum cfc-DNA Purification Midi Kit (Product # 55600) was used to separate cffDNA. Two PCR-designed primers named SRY-137 and GAPDH-109 were employed to amplify the Y-chromosome-specific sequences SRY and the housekeeping gene GAPDH, respectively. The fetal sex was indicated by PCR data corresponding to the calf's sex at birth in 11 cases. The study's findings first proved the existence of cell-free fetal DNA circulating in the plasma of a pregnant cow in Vietnam and established the calf's sex using simple, high-precision procedures. The use of cffDNA for sex screening brings up the possibility of quickly determining the gender and screening for genetic diseases in a big herd of cattle and animals with long gestation periods.
Miana (Coleus scutellariodes) Inhibits Nuclear Factor-kappa B (NF-kB) Activity and its Antibacterial and Anti-inflammatory Benefits in Infectious Diseases: Review Article
Authors: Junita Ade Rifka , Hamid Firdaus , Budu Budu , Natzir Rosdiana , Hala Yusmina , Alam Gemini , Agus Rosana , Bahar Burhanuddin , Syukri Ahmad , Primaguna Muhammad Reza , Dwiyanti Ressy , Febriant Andini , Azhar Azhar , Hatta Mochammad
Published: October 2023

Background: Miana, also known as Coleus scutellariodes, is a supplement agent frequently used to treat infectious disorders. Its antibacterial and anti-inflammatory mechanisms are not well understood. Nuclear factor-kappa B (NF-kB), which acts as a major regulator in these infectious processes, strongly induces proinflammatory cytokines via I-kB through its connection with the NF-kB receptor, which affects cytokine production, and angiogenesis via the role of VEGF and HIF-1. VEGF is an angiogenic factor that can trigger cellular responses on the surface of endothelial cells via the NF-kB pathway. HIF-1 has a critical role in the cellular response to systemic oxygen levels of cells. This article's objective is to provide a thorough analysis of molecular mechanisms of NF-kB in relation to infectious diseases treated by Miana. Methods: To obtain the data for this study, relevant reference lists were manually searched in the PubMed, EMBASE, and Scopus databases using the keywords "Miana", "Coleus scutellariodes", "NF-kB", "antibacterial", "anti-inflammation" and "Infectious diseases." as significant reference lists. This review article included and narratively covered each appropriate article from the database above. Results: It was found in several articles that NF-kB and molecular mechanisms of Miana in infectious diseases are strongly related, and that these mechanisms may be used to cure and prevent infectious diseases. The molecular mechanism of Miana containing the active component of flavonoids is broad and complex, in which the induced NF-kB has two main pathways, namely canonical and non-canonical initially from the upstream and downstream of NF-kB activities and there is intricate crosstalk of NF-kB. Conclusions: Miana treats infectious diseases through NF-kB, which functions mainly through a variety of mechanisms. Miana's treatment of infectious diseases with NF-kB leads to the conclusion that NF-kB is a stimulator of several proinflammatory cytokines. Additionally, Miana can reduce HIF-1 expression, and HIF-1 is also in function of upregulating some angiogenic factors in infectious diseases, therefore Miana may suppress NF-kB activities both in vitro and in vivo. Miana contains an active component of flavonoid, which has broad capabilities in both inflammatory and non-inflammatory processes, thus research is urgently needed that links from upstream to downstream of its molecular mechanisms. Besides that, a more detailed study is needed on the intricate crosstalk in the inflammatory process due to microorganism infection through NF-kB activity in Miana interventions containing flavonoid active substances.
Antioxidant, Antibacterial and Cytotoxic Activities of Artemisia judaica, Ruta graveolens and Suaeda monoica from Saudi Arabia
Authors: Ncibi Saida S. , M. Madkhali Aymen, , E. Oraiby Magbool , A. Almalki Jamilah , Khadashi Hussein A. , A. Mobarki Abdullah , Mohan Syam , A. Hamali Hassan
Published: October 2023

Artemisia judaica, Ruta graveolens, and Suaeda monoica, indigenous plants to Jazan, second smallest region of Saudi Arabia, have several uses in the local folk medicine. This research aims to study the chemical composition of their methanol extracts and to explore some related biological activities. The different extracts Gas Chromatography Mass Spectroscopy profiling revealed the occurrence of many compounds within these extracts. Besides, this study revealed varied and selective antibacterial activities of these extracts. Ruta graveolens methanol extract was effective in inhibiting the growth of all tested microorganisms. Furthermore, they exhibit an interesting cytotoxic effect on human breast cancer cell lines, especially Artemisia judaica methanol extract. These findings suggested that Artemisia judaica (Asteraceae), Ruta graveolens (Rutaceae), and Suaeda monoica (Chenopodiaceae) could be natural sources for the discovery of new drugs.
Evrópuvæðing Íslands
Authors: Bergmann Eiríkur
Published: October 2023

Ísland er eina ríki Norðurlanda sem aldrei hefur sótt um aðild að Evrópusambandinu og telst þeirra tregast í taumi í Evrópusamvinnunni. Eigi að síður hefur Evrópusamruninn haft afgerandi áhrif á þróun íslensks þjóðfélags í gegnum aðildina að Evrópska efnahagssvæðinu (EES). Fyrst og fremst með almennri frelsisvæðingu atvinnulífsins sem losað var undan oki margvíslegra hafta, en einnig með stórauknu samstarfi við Evrópuþjóðir á ýmsum sviðum, svo sem í viðskiptum, vísindum, menntun og á menningarsviðinu. Áhrif Evrópusamvinnunnar teygja sig núorðið til flestra sviða þjóðfélagsins og hafa leitt til grundvallarbreytingar á íslenskri þjóðfélagsgerð, til að mynda hvað varðar umhverfisvernd, matvælaeftirlit og vinnuréttarmál svo dæmi séu tekin af nokkrum ólíkum sviðum. Að auki tekur Ísland nú fullan þátt í Schengen-landamærasamstarfi ESB og Dyflinar-samkomulaginu svokallaða með sérstöku samkomulagi sem gert var við Ísland og Noreg. Það gefur því augaleið að ein frumforsenda þess að skilja þróun íslensks samfélags undanfarin ár felst í að rannsaka og skoða hvernig Evrópuvæðingin hefur haft áhrif hér á landi. Þetta hefur því miður verið vanrækt mjög, en svo virðist sem þraskennt stappið um hugsanlega Evrópusambandsaðild hafi í raun komið í veg fyrir að áhrif Evrópuvæðingarinnar á íslenskt samfélag hafi verið rannsökuð með kerfisbundnum hætti. Þess í stað hafa sumir stjórnmálamenn frekar viljað draga upp þá mynd af stöðu okkar í Evrópusamrunann sem hentar þeirra eigin afstöðu til ESB-aðildar.
Audre Lorde, Labor Theorist: Rethinking Integrity within Late Capitalism
Authors: Popiel Kristina
Published: October 2023

Abstract: Audre Lorde’s work is most often read for her insights in the fields of gender, sexuality, and critical race theory, and while her work certainly merits close attention for its groundbreaking contributions to these fields, I will suggest here that her work can also be productively read as a significant contribution to literary labor theory. Reading Lorde as a labor theorist enables a holistic understanding of the complete nexus of race, gender, sexuality, and class as the materialist manifestation of the underlying capitalistic abstraction of the self of the worker. I will argue that for Lorde, ultimately, woman is one who works, and this underlies her overarching conceptualization of integrity, a radical notion of wholeness that is based in the fullness of women’s labor (often social justice labor). This materialist idea functions as a radical alternative to capitalist alienation, and specifically combats the privilege of white feminism, and other bourgeois power inequalities. Lorde’s conceptualization of the working woman of color is truly world-making. It is sensuous and holistic (in a way that the abstraction of capitalism is demonstratively not), and it is a specifically non-white, lesbian labor that effects this. Lorde’s “integrity” is a way of reuniting the subject and object (à la Marx’s “species being”) within the figure of the woman who works. What that looks like, in our political reality, is active social justice work, done—and lived—with integrity.
Historic Designation Planning for the Nicodemus National Historic Site and Colonel Allensworth State Historic Park: A Cross-Case Analysis of Representation in Public Memory, Equity-Based Preservation Planning, and Maintenance Backlogs
Authors: Adams Ashley C. , Edges Alec C.
Published: October 2023

Abstract: The hidden histories of Black towns from post-Reconstruction, namely Nicodemus, Kansas, and Colonel Allensworth, California, can provide public awareness of the black experience. In this article, we draw upon previous research by the authors to further emphasize and compare designation outcomes related to representation, equity-based preservation planning, and maintenance backlogs issues. Key partners from both sites were interviewed and central preservation planning documents were analyzed. Key findings emphasized limited opportunities for community involvement, and historic structures preservation and maintenance work. Additionally, some action has been taken by the National Park Service and California State Parks to improve diversity, equity, and inclusion. Despite these efforts, there are still alarming indicators of systematic underrepresentation within both systems. Recommendations and best practices include increasing racial equity and diversity training, evaluating diversity hiring practices and public memory awareness, practicing inclusive partnership planning, redesigning maintenance backlog funding systems, engaging economic revitalization, practicing inclusive and digitally enhanced programming, and expanding virtual presence. Consideration of this study's recommendations could provide meaningful preservation change for the Nicodemus National Historic Site, Allensworth State Historic Park, and other similar African American historical locations.
Redessiner les archives familiales: Mise en tensions graphiques dans Les Jardins du Congo de Nicolas Pitz et Elle ne parlait jamais du Congo de Nicolas Wouters
Authors: Lambert Alicia
Published: October 2023

Abstract: Cet article examine la manière dont les bandes dessinées Les Jardins du Congo (2013), de Nicolas Pitz, et Elle ne parlait jamais du Congo (2017), de Nicolas Wouters, revisitent les archives familiales dont les artistes ont hérité de leurs grands-parents ayant vécu au Congo belge. L’analyse examine comment, dans ces démarches postmémorielles, plusieurs tensions graphiques, textuelles, visuelles, séquentielles et tabulaires révèlent d’autres tensions idéologiques, qui témoignent d’un conflit mémoriel entre deux générations. Les artistes prennent en main les archives familiales—ils sélectionnent, manipulent, cadrent, redessinent—afin de dévoiler les absences et les hypocrisies qui caractérisent des images idéalisées et simplifiées. Les œuvres montrent ainsi la capacité que possède la bande dessinée de décentrer les archives et le regard colonial, tout en attirant l’attention sur leur propre subjectivité et leur propre ambivalence.
Democracy and Mass Skepticism of Science
Authors: Jiang Junyan , Wan Kinman
Published: October 2023

abstract: Since the Age of Enlightenment, many thinkers and philosophers have viewed democracy and science as two aspects of modernity that reinforce each other. This article highlights a tension between the two by arguing that certain aspects of contemporary democracy may aggravate the mass public's anti-intellectual tendency and thus potentially hinder scientific progress. The authors analyze a new global survey of public opinion on science using empirical strategies that exploit cross-country and cross-cohort variations in experience with democracy, and show that less-educated citizens in democracies distrust science much more than do their counterparts in nondemocracies. Further analyses suggest that the increase in skepticism in democracies is not the result of greater religiosity or weaker scientific literacy; instead, it is more likely driven by a shift in the mode of legitimation, which reduces states' ability and willingness to act as key public advocates for science. These findings shed light on the institutional sources of science-bashing in many longstanding democracies.
Scalable laser-based underwater wireless optical communication solution between autonomous underwater vehicle fleets
Authors: Weng Yang , Sekimori Yuki , Chun Sehwa , Alkhazragi Omar , Matsuda Takumi , Trichili Abderrahmen , Ng Tien Khee , Ooi Boon S. , Maki Toshihiro
Published: October 2023

The development of multiple autonomous underwater vehicles (AUVs) has
revolutionized the traditional reliance on a single, costly AUV for
conducting underwater surveys. This shift has garnered increasing
interest among marine researchers. Communication between AUV fleets is
an urgent concern due to the data rate limitation of underwater
acoustic communication. Laser-based underwater wireless optical
communication (UWOC) is a potential solution once the
link-establishing requirement between AUVs can be met. Due to the
limited coverage area of the laser beam, the previous pointing,
acquisition, and tracking (PAT) method is to quickly adjust the beam
direction and search for the target according to the set scanning
path. In response to these challenges, we propose a scalable
laser-based link establishment method that combines the maneuvering of
the AUV, the acoustic positioning, and the control of the optical
system. Our proposed approach has consistently outperformed the
existing PAT method in simulated environments, effectively
establishing laser links. Importantly, we have successfully
implemented our approach in machine experiments, confirming its
practical applicability.
Polarization enhanced two-photon excited fluorescence contrast by shaped laser pulses using a deformable phase plate
Authors: Bukhari Syed Shakir Ashraf Shah , Halder Ayan , Lindinger Albrecht
Published: October 2023

We utilize spatially and temporally tailored laser pulses for polarization enhanced two-photon excited fluorescence contrasts of dyes. The shaped laser pulses are produced by first passing through a temporal pulse shaper and then through a two-dimensional spatial pulse shaper with deformable phase plates. Different spatial beam profiles are presented that demonstrate the potential of the spatial pulse shaper. Particularly, a polarization enhanced fluorescence contrast between two dyes is reported by utilizing specific phase shaping in perpendicular polarization directions. The tailored laser pulses are further modified by the deformable phase plate, and a polarization increased depth-dependent contrast is achieved. This spatial shaping for all polarization directions demonstrates the advantage of deformable phase plate spatial shapers compared to liquid crystals, where only one polarization direction can spatially be modified. The described polarization contrast method allows for three-dimensional scanning of probes and provides perspectives for biophotonic applications.
Optical adaptive power control based on atmospheric channel reciprocity for mitigating turbulence disturbances in free-space optics
communication
Authors: Yao Haifeng , Wang Weihao , Zhou Chang , Cao Jie , Hao Qun , Chen Chunyi , Dong Keyan , Tong Shoufeng , Liu Zhi , Liu Xianzhu , Jiang Huilin
Published: October 2023

A continuous time-domain adaptive power model of transmitter optical and control algorithm based on atmospheric turbulence channel
reciprocity are explored for mitigating the free-space optical communication (FSOC) receiver optical intensity scintillation and bit error
rate (BER) deterioration. First, a transmitter optical adaptive power control (OAPC) system architecture using four wavelength optical
signals based on atmospheric turbulence channel reciprocity is proposed, and electronically variable optical attenuator (EVOA) and
erbium-doped fiber amplifier (EDFA) are employed as the main OAPC units for power adaptation. Moreover, a reciprocity evaluation model for
gamma-gamma (G-G) continuous-time signals is generated using the autoregressive moving average (ARMA) stochastic process, which takes into
account the delay time and system noise, and a reciprocity-based OPAC algorithm is proposed. Numerical simulations were also performed to
analyze the signal reciprocity characteristics under different turbulence, noise, and sampling time mismatch at both ends, as well as the
scintillation index (SI) performance under OAPC system operation. Simultaneously, the time-domain signals of continuous quadrature amplitude
modulation -16 (QAM-16) and QAM-32 real states are fused with the gamma-gamma (G-G) reciprocal turbulence continuous signals to analyze the
probability density function (PDF) and bit error ratio (BER) performance after OAPC correction. Finally, a 64 Gpbs QAM-16 OPAC communication
experiment was successfully executed based on an atmospheric turbulence simulator. It is shown that the OAPC correction is carried out using
reciprocity at millisecond sampling delay, the light intensity scintillation of the communication signal can be well suppressed, the
signal-to-noise ratio (SNR) is greatly improved, the suppression is more obvious under strong turbulence, the overall BER reduction is
greater than 2.8 orders of magnitude with the OAPC system, and this trend becomes more pronounced as the received power increases, even
reach 6 orders of magnitude in some places. This work provides real time-domain continuous signal samples for real signal generation of
communication signals in real turbulence environments, adaptive coding modulation using reciprocity, channel estimation, and optical
wavefront adaptive suppression, which are the basis of advanced adaptive signal processing algorithms.
Kerr microresonator dual-comb source with adjustable line-spacing
Authors: Qureshi Pierce C. , Ng Vincent , Azeem Farhan , Trainor Luke S. , Schwefel Harald G. , Coen Stéphane , Erkintalo Miro , Murdoch Stuart G.
Published: October 2023

Optical microresonators offer a highly-attractive new platform for the generation of optical frequency combs. Recently, several groups have been able to demonstrate the generation of dual-frequency combs in a single microresonator driven by two optical pumps. This opens the possibility for microresonator-based dual-comb systems suitable for measurement applications such as spectroscopy, ranging and imaging. Key to the performance of these systems are the parameters of the radio-frequency comb spectrum that arises from the interference of the two optical combs. In this work, we present a simple mechanism to enable the discrete fine-tuning of these parameters by driving the two optical combs with optical pumps with different azimuthal mode numbers. The mechanism consists of tuning the difference in azimuthal mode number between the two pumps by selection of the pumps’ frequencies. We are able to implement this technique when the two counter-propagating pumps are set to drive resonances of the same spatial mode family, as well as different mode families. In each case, we experimentally observe ∼1 MHz of discrete tunability in the line-spacing of the radio-frequency comb as the frequency offset between the two pumps is scanned between 0 to 80 free-spectral-ranges.
Waveguide-integrated chip-scale optomechanical magnetometer
Authors: Gotardo Fernando , Carey Benjamin J. , Greenall Hamish , Harris Glen I. , Romero Erick , Bulla Douglas , Bridge Elizabeth M. , Bennett James S. , Foster Scott , Bowen Warwick P.
Published: October 2023

Optomechanical magnetometers enable highly sensitive magnetic field sensing. However, all such magnetometers to date have been optically excited and read-out either via free space or a tapered optical fiber. This limits their scalability and integrability, and ultimately their range of applications. Here, we present an optomechanical magnetometer that is excited and read-out via a suspended optical waveguide fabricated on the same silicon chip as the magnetometer. Moreover, we demonstrate that thermomechanical noise limited sensitivity is possible using portable electronics and laser. The magnetometer employs a silica microdisk resonator selectively sputtered with a magnetostrictive film of galfenol (FeGa) which induces a resonant frequency shift in response to an external magnetic field. Experimental results reveal the retention of high quality-factor optical whispering gallery mode resonances whilst also demonstrating high sensitivity and dynamic range in ambient conditions. The use of off-the-shelf portable electronics without compromising sensor performance demonstrates promise for applications.
High stability white light generation in water at multi-kilohertz repetition rates
Authors: Keller Kilian Richard , Rojas-Aedo Ricardo , Vanderhaegen Aline , Ludwig Markus , Brida Daniele
Published: October 2023

An efficient supercontinuum (SC) generation featuring high spectral intensity across a large bandwidth requires high peak powers of several megawatts from pulsed lasers. Under these conditions and at multi-kilohertz (kHz) repetition rates, the SC generated in most materials is unstable due to thermal effects. In this work, we leverage the superior dispersion properties of water to maximize the spectral width of the SC, while avoiding stability issues due to thermal loading by means of a constant laminar flow of the liquid. This flow is controlled by a differential pressure scheme that allows to precisely adjust the fluid velocity to an optimum value for maximum stability of the SC. This approach is successfully implemented for repetition rates of 50 kHz and 100 kHz and two different pump wavelengths in the visible (VIS) and near infrared (NIR) spectral region with stability of the SC signal only limited by the driving pulses. The resulting water SC spans more than one octave covering the VIS to NIR range. Compared to established materials, such as yttrium aluminum garnet (YAG) and sapphire, the spectral bandwidth is increased by 60% and 40% respectively. Our scheme has the potential to be implemented with other liquids such as bromine or carbon disulfide (CS2), which promise even wider broadening and operation up to the mid-infrared.
Enhancing harmonic brightness near the cutoff region by using laser pulses with a small positive chirp
Authors: Qiao Yue , Wang Xinyu , Li Xuefeng , Wu Linyan , Yu Ruixian , Guo Fuming , Wang Jun , Chen Jigen , Yang Yujun
Published: October 2023

Efficient enhancement of harmonic brightness near the cutoff region is achieved by employing laser pulses with a small positive chirp in theory, where the laser intensity and frequency near the peak of the laser pulse are almost unchanged relative to the chirp-free field. The improvement of harmonic brightness is achieved under the condition that the ionization probability is almost unchanged. Through the analysis of the harmonics contributed by the rising and falling parts of the laser pulse, we have uncovered a "frequency compensation" mechanism that leads to an enhanced harmonic brightness near the cutoff region. Under appropriate chirp parameters, the harmonics contributed by the rising and falling parts can be constructively interfered in a smaller frequency range with greater intensity, thereby obtaining harmonics with good monochromaticity and high brightness. This study explains the mechanism of harmonic brightness enhancement from a new perspective, and provides a new idea for harmonic regulation without changing the ionization.
Modelling structural colour from helicoidal multi-layer thin films with natural disorder
Authors: Davis T. J. , Ospina-Rozo L. , Stuart-Fox D. , Roberts A.
Published: October 2023

A coupled mode theory based on Takagi-Taupin equations describing electromagnetic scattering from distorted periodic arrays is applied to the problem of light scattering from beetles. We extend the method to include perturbations in the permittivity tensor to helicoidal arrays seen in many species of scarab beetle and optically anisotropic layered materials more generally. This extension permits analysis of typical dislocations arising from the biological assembly process and the presence of other structures in the elytra. We show that by extracting structural information from transmission electron microscopy data, including characteristic disorder parameters, good agreement with spectral specular and non-specular reflectance measurements is obtained.
Impacts of p-GaN layer thickness on the photoelectric and thermal performance of AlGaN-based deep-UV LEDs
Authors: Li Saijun , Shen Meng-Chun , Lai Shouqiang , Dai Yurong , Chen Jinlan , Zheng Lijie , Zhu Lihong , Chen Guolong , Lin Su-Hui , Peng Kang-Wei , Chen Zhong , Wu Tingzhu
Published: October 2023

The effects of different p-GaN layer thickness on the photoelectric and thermal properties of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) were investigated. The results revealed that appropriate thinning of the p-GaN layer enhances the photoelectric performance and thermal stability of DUV-LEDs, reducing current crowding effects that affect the external quantum efficiency and chip heat dissipation. The ABC + f(n) model was used to analyse the EQE, which helped in identifying the different physical mechanisms for DUV-LEDs with different p-GaN layer thickness. Moreover, the finite difference time domain simulation results revealed that the light-extraction efficiency of the DUV-LEDs exhibits a trend similar to that of damped vibration as the thickness of the p-GaN layer increases. The AlGaN-based DUV-LED with a p-GaN layer thickness of 20 nm exhibited the best photoelectric characteristics and thermal stability.
Enhancing long-term frequency stability of a single-mode optoelectronic oscillator based on phase conjugation
Authors: Wang Tao , Tian Chen , Zhang Kaiyu , Liu Jinyang , Xie Zhengyang , Zhao Xin , Li Shangyuan , Zheng Zheng
Published: October 2023

We propose and experimentally demonstrate what we believe to be a novel single-mode optoelectronic oscillator (OEO) with low frequency drift based on phase conjugation. The long-term frequency stabilization of the OEO is achieved by using photonic microwave phase-conjugate passive compensation. Besides, since there happens to be a nonlinear coupled double loop structure in the OEO, single-mode oscillation can be achieved. The experimental results show that the side mode suppression ratio (SMSR) of the radio frequency (RF) signal from the OEO at 9.93 GHz is enhanced from 5 dB to 68 dB after side mode suppression, and the maximum frequency drift within 600 s reduced from 1.51 ppm to 0.04 ppm, optimized by a factor of about 40. The OEO has a simple structure, no external injection, and the phase noise is not limited by the injected signal.
Method for designing ultra-wideband absorbers based on water-filled Fabry–Perot cavity with continuously varying cavity length
Authors: Zhong Zheqiang , Wu Qiuxia , Ling Fang , Zhang Bin
Published: October 2023

Broadband and efficient terahertz (THz) absorbers are crucial for various applications in sensing, imaging, detecting, and modulation. Although recent studies have reported a series of THz metamaterials for enhanced absorption, achieving high absorption across the entire ultrabroad terahertz band remains challenging. We propose a novel, to the best of our knowledge, method to design ultra-wideband terahertz absorbers using a water-filled Fabry–Perot cavity with continuously varying cavity length. Our design achieves over 90% absorption across an ultrabroad terahertz band ranging from 0.26 to 30 THz. Furthermore, the design method can be extended to the visible, infrared, and microwave regimes. We believe that our method will inspire further studies and applications of ultra-wideband absorbers.
GPU-enabled real-time optical frequency comb spectroscopy and a photonic readout
Authors: Bresler S. M. , Long D. A. , Reschovsky B. J. , Bao Y. , LeBrun T. W. , Gorman J. J.
Published: October 2023

We describe a GPU-enabled approach for real-time optical frequency comb spectroscopy in which data is recorded, Fourier transformed, normalized, and fit at data rates up to 2.2 GB/s. As an initial demonstration we have applied this approach to rapidly interrogate the motion of an optomechanical accelerometer through the use of an electro-optic frequency comb. We note that this approach is readily amenable to both self-heterodyne and dual-comb spectrometers for molecular spectroscopy as well as a photonic readout where the approach’s agility, speed, and simplicity are expected to enable future improvements and applications.
Limited view correction in low-optical-NA photoacoustic microscopy
Authors: Shen Hao , Liu Xiangru , Cui Qi , Sun Yunxu , Yang Bing , Li Fenfang , Xu Xiaochuan , Liu Zhengjun , Liu Wei
Published: October 2023

Photoacoustic microscope (PAM) with a low-optical NA suffers from a limited view along the optical axis, due to the coherent cancellation of acoustic pressure waves after being excited with a smoothly focused beam. Using larger-NA (NA > 0.3) objectives can readily overcome the limited-view problem, while the consequences are the shallow working distance and time-consuming depth scanning for large-volume imaging. Instead, we report an off-axis oblique detection strategy that is compatible with a low-optical-NA PAM for turning up the optical-axis structures. Comprehensive photoacoustic modeling and ex vivo phantom and in vivo mouse brain imaging experiments are conducted to validate the efficacy of correcting the limited view. Proof-of-concept experiment results show that the visibility of optical-axis structures can be greatly enhanced by making the detection angle off the optical axis larger than 45°, strongly recommending that off-axis oblique detection is a simple and cost-effective alternative method to solve the limited-view problems in low-optical-NA PAMs.
Burst-mode Velocimetry of Hypersonic Flow by Nitric-oxide Ionization Induced Flow Tagged Imaging
Authors: Leonov Boris , Moran Ashley , North Simon , Miles Richard
Published: October 2023

This letter describes a new approach to flow tagging, Nitric-oxide Ionization Induced Flow Tagged Imaging (NiiFTI), and presents the first experimental demonstration for single-shot velocimetry in a near Mach 6 hypersonic flow at 250 kHz. The mean velocity of 860 m/s was measured with a single-shot standard deviation of as low as 3.4 m/s and mean velocity uncertainty of 5.5 m/s. NiiFTI is characterized by a long fluorescence lifetime of nitrogen with 1/e decay of approximately 50 μs measured in air. The method relies on a single nanosecond laser combined with a high-speed camera, creating an opportunity for the utilization of a typical NO Laser-Induced Fluorescence (LIF) experimental setup with minor modifications as well as Pulse-Burst Lasers (PBLs) for ultra-high repetition rates.
Rapid runtime learning by curating small datasets of high-quality items obtained from memory
Authors: German Joseph Scott , Cui Guofeng , Xu Chenliang , Jacobs Robert A.
Published: October 2023

We propose the “runtime learning” hypothesis which states that people quickly learn to perform unfamiliar tasks as the tasks arise by using task-relevant instances of concepts stored in memory during mental training. To make learning rapid, the hypothesis claims that only a few class instances are used, but these instances are especially valuable for training. The paper motivates the hypothesis by describing related ideas from the cognitive science and machine learning literatures. Using computer simulation, we show that deep neural networks (DNNs) can learn effectively from small, curated training sets, and that valuable training items tend to lie toward the centers of data item clusters in an abstract feature space. In a series of three behavioral experiments, we show that people can also learn effectively from small, curated training sets. Critically, we find that participant reaction times and fitted drift rates are best accounted for by the confidences of DNNs trained on small datasets of highly valuable items. We conclude that the runtime learning hypothesis is a novel conjecture about the relationship between learning and memory with the potential for explaining a wide variety of cognitive phenomena.
Experiences and practices of traditional healers on snakebite treatment and prevention in rural Malawi
Authors: Aron Moses Banda , Mulwafu Manuel , Mailosi Bright , Kreuels Benno , Dullie Luckson , Kachimanga Chiyembekezo , Blessmann Jörg , Ndarama Enoch , Sambani Clara , Munyaneza Fabien , Rosenthal Anat
Published: October 2023

Snakebite envenoming remains a public health threat in many tropical countries including Malawi. Traditional healers (THs) have been consulted by victims of snakebites as primary caregivers for millennia. There are no studies in Malawi to understand this phenomenon, therefore, our study aimed to explore the experiences and practices of THs regarding snakebite treatment and prevention in rural Malawi. Between August and September 2022, we conducted semi-structured interviews with 16 THs who were purposefully selected from various locations across Neno District, Malawi. We analysed the interview data using Dedoose software, where we generated codes and grouped them into themes. Out of the 16 THs interviewed, 68.8% (n = 11) were male, and 43.8% were aged between 40 and 60 years. Our study identified five themes: THs’ knowledge of snakes and treatment, the continuum of care they provide, payment procedures, snakebite prevention, and their relationship with health facilities. They claimed a good understanding of the snakes in their area, including the seasons with more snakebites, and were confident in their ability to provide treatment, however, this was not scientifically proven. They offered a comprehensive care package, including diagnosis, first aid, main treatment, and follow-up care to monitor the victim’s condition and adjust treatment as needed. THs provide free treatment for snakebites or use a “pay later” model of service delivery. All THs claimed a “vaccine” for snakebites that could prevent bites or neutralize the venom. However, no formal relationship existed between THs and Health Care Workers (HCWs). We recommend collaboration between HCWs and THs, establishing clear referral pathways for snakebite victims and educating THs on identifying danger signs requiring prompt referral to healthcare facilities.
Educating the next generation of cancer researchers: Evaluation of a cancer research partnership training program
Authors: Zhu Lin , Dodd S. J. , Chen Yuku , Kaminsky Emily R. , Liu Zhiqing Elaine , Ma Grace X. , Ogunwobi Olorunseun O. , Fang Carolyn Y.
Published: October 2023

African American, American Indian and Alaska Native, Hispanic (or Latinx), Native Hawaiian, and other Pacific Islander groups are underrepresented in the biomedical workforce, which is one of the barriers to addressing cancer disparities among minority populations. The creation of a more inclusive biomedical workforce dedicated to reducing the burden of cancer health disparities requires structured, mentored research and cancer-related research exposure during the earlier stages of training. The Summer Cancer Research Institute (SCRI) is a multicomponent 8-week intensive summer program funded under the Partnership between a Minority Serving Institute and a National Institutes of Health-designated Comprehensive Cancer Center. In this survey study, we found that students who participated in the SCRI Program reported greater knowledge and interest in pursuing careers in cancer-related fields than their counterparts who did not participate in SCRI. Successes, challenges, and solutions in providing training in cancer and cancer health disparities research to improve diversity in the biomedical fields were also discussed.