bluuebunny/crossref_metadata_2025 huggingface dataset:
Toxic Neighborhoods: The Effects of Concentrated Poverty and Environmental Lead Contamination on Early Childhood Development
Authors: Wodtke Geoffrey T. , Ramaj Sagi , Schachner Jared
Published: June 2022

Although socioeconomic disparities in cognitive ability emerge early in the life course, most research on the consequences of living in a disadvantaged neighborhood has focused on school-age children or adolescents. In this study, we outline and test a theoretical model of neighborhood effects on cognitive development during early childhood that highlights the mediating role of exposure to neurotoxic lead. To evaluate this model, we follow 1,266 children in Chicago from birth through school entry and track both their areal risk of lead exposure and their neighborhoods' socioeconomic composition over time. With these data, we estimate the joint effects of neighborhood poverty and environmental lead contamination on receptive vocabulary ability. We find that sustained exposure to disadvantaged neighborhoods reduces vocabulary skills during early childhood and that this effect operates through a causal mechanism involving lead contamination.
Emerging interplay of cytoskeletal architecture, cytomechanics and pluripotency
Authors: Liu Shiying , Kanchanawong Pakorn
Published: June 2022

Pluripotent stem cells (PSCs) are capable of differentiating into all three germ layers and trophoblasts, whereas tissue-specific adult stem cells have a more limited lineage potency. Although the importance of the cytoskeletal architecture and cytomechanical properties in adult stem cell differentiation have been widely appreciated, how they contribute to mechanotransduction in PSCs is less well understood. Here, we discuss recent insights into the interplay of cellular architecture, cell mechanics and the pluripotent states of PSCs. Notably, the distinctive cytomechanical and morphodynamic profiles of PSCs are accompanied by a number of unique molecular mechanisms. The extent to which such mechanobiological signatures are intertwined with pluripotency regulation remains an open question that may have important implications in developmental morphogenesis and regenerative medicine.
Acidity Controlled Desulfurization of Biogas by Using Iron (III) and Ferrosoferric (II, III) Oxide
Authors: Al Mamun Muhammad Rashed , Abu Yusuf Mohammad , Bhuyan Md Murshed , Bhuiyan Md Shohag Hossain , Arafath Md Azharul , Uddin Md Nizam , Soeb Md Janibul Alam , Almahri Albandary , Rahman Mohammed M , Karim Mohammad Razaul
Published: June 2022

Removal of hydrogen sulfide (H2S) from raw biogas is essential for feeding the refined gas with high methane (CH4) content in engines and combustion units. In small-scale farmhouses and power plants, a cheap, inexpensive, and facile desulfurization process is needed. Herein, the desulfurization process of biogas by treating with Fe2O3 and nanoscaled Ferrosoferric oxide (FeF) suspension is presented. The treatment process includes both the chemical reaction and physical adsorption phenomena. With variable pH and treatment duration, efficient desulfurization of the biogas was achieved. The optimum pH for H2S removal was 5 at which the removal efficiency was 97% for Fe2O3 solution and 95% for FeF solution. Respectively, CH4 content increased above 75%. The H2S-concentration dropped by 50 ppm from the initial value. The H2S content in the purified gas is thus reduced below the recommended limit for running internal combustion engines. We suggest some physicochemical elimination of the H2S fraction. The process might be feasible to utilize in small farmhouses and power units.
Effectiveness of Integrated Emotional-Self Enhancement (IESE) program among staff nurses: protocol for a quasi-experimental study
Authors: Saikia Monalisa , George Linu Sara , Unnikrishnan Bhaskaran , George Anice , Ravishankar N
Published: June 2022

Background: Staff nurses face frequent emotional situations in their work environment. The constant contact with suffering patients, and the busy work environment, pose tremendous stress on nurses' physical and emotional health. The Emotional Intelligence skills of empathy, self-awareness, motivation, self-control, and keeping relationships, can help handle difficult emotions and allow nurses to work in an organized, calm, and professional way.

This study aims to implement and assess the effectiveness of a training program developed by the investigator, tailored to the mental and emotional needs of staff nurses who are working in an organization. The study also aims to observe any significant change, correlation, and association in the staff nurses’ level of emotional intelligence, intrinsic motivation, self-compassion, emotional labor, and nurse-in-charges’ and patients’ perception of nursing care after the program.

Methods: A quasi-experimental (one-group) study design was used in this study. The study will involve 80 staff nurses working in a selected hospital in India. The staff nurses will be selected from the hospital's general wards using convenience sampling. For the current study, a quasi-experimental design will be used. The investigator will deliver a training program, divided into four sessions of two hours each. Data will be collected from the participants at baseline and 3-months pre-intervention; and post-test data will be collected immediately after the intervention, at 3-month, and 6-month follow-up, to observe any significant change in the study variables before and after the intervention.

Results: The current study primarily focuses on the vital aspect of developing emotional needs, for promoting a better work-life balance. Research findings from the study will significantly contribute to the evidence based Emotional Intelligence programs for staff nurses, and if proven effective, could be delivered extensively in the hospitals.

Trial registration: The study is registered in June 2019 under the Central Trial Registry of India (CTRI/2019/08/020592).
Characterizing intercampus migration in a private university of Baja California, Mexico
Authors: Beltrán Lucia , Gibaja-Romero Damián-Emilio , Cantón-Croda Rosa-María
Published: June 2022

Given the socioeconomic and environmental differences between Mexico’s geographical regions, having a multi-campus system is common for private and public universities. Hence, students may choose to migrate from one campus to another. Although such a phenomenon is not properly students’ desertion, students’ migration impacts campus’ main indicators: enrollment growth goals, terminal efficiency, accreditation programs, and revenue. Thus, the campus of origin internalizes migration as students’ desertion. By considering a campus from a private multi-campus university in Baja California, Mexico, this study characterizes and predicts students’ migration and predicts by determining the socioeconomic and academic variables that impact the probability of moving to a different campus. Our database comprises quantitative and qualitative information of 356 dropout students from 2008 to 2018. Hence, we apply the logistic regression technique to build a predictive model; we found that the most significant predictive variables are the GPA results, age, financial support, and academic development. So, our main results characterize migrant students as having top grades, coming from the high school campus, and attending engineering programs. Surprisingly, economic variables are not significant in choosing to migrate from one campus to another.
A cross-sectional study of Malaysian low-income drug addict wives: Relationship between family impact, coping and mental wellbeing
Authors: Adnan Haikal Anuar , Arshat Zarinah , Ahmad Shahril Nurul Saidatus Shaja’ah
Published: June 2022

Background: The involvement of the husbands in the issue of drug addiction has impacted the wives’ livelihoods. Due to drug addiction amongst husbands, the wives experience stress and strain. The Stress Strain Coping Support Model (SSCS) was established to better comprehend how coping influences stress and strain. Thus, the purpose of this study was to determine the relationship between the stress which refers to family impact experienced by the wives of drug addicts, in terms of economic difficulties and marital conflict, and mental wellbeing. Furthermore, this study examines the role of coping as a mediating factor between family impact and mental wellbeing.

Methods: This study involved 132 wives of low-income drug addicts in Malaysia, who were selected using a purposive sampling method. Economic Strain Scale (ESS) and Braiker-Kelly Marital Conflict Scale (BKMCS) were used to measure family impact. Coping and Adaptation Processing Scale Short Form (CAPS-SF) and Short Warwick-Edinburgh Mental Wellbeing Scale (SWEMWBS) were used to measure coping and mental wellbeing of the respective respondents.

Results: Path analysis using SmartPLS software version 3.3.7 showed that there is a direct association between family impact and coping, and between coping and mental wellbeing. The results also showed that family impact was associated indirectly with mental wellbeing through coping. 

Conclusions: The findings benefited drug addict wives and practitioners related to this field in terms of enhancing the use of coping mechanisms in managing family impact and improving mental wellbeing, specifically amongst low-income drug addict wives.
Managing health care needs of the elderly through an elderly care manager: Thailand
Authors: Ploylearmsang Chanuttha , Somboon Chutamat , Namdee Utoomporn , Suttiruksa Saithip
Published: June 2022

Background: This mixed method research aimed to investigate health needs of older people and the attributes of the Elderly Care Managers (ECMs), and to evaluate the outcomes of two ECMs coordination.

Methods: Three phases were: 1) a field survey of the health needs of 94 older persons; 2) group discussions between ten relevant persons involved in ECMs characteristics; 3) two ECMs coordinating with health-related agencies and measuring the outcomes of older people who needed assistance.

Results: 63.1% of the participants had difficulties with their health, 12.8% of them had no caregiver, 26.6% of them had >1 health condition. Group talks dealt with the characteristics, role and attributes of ECMs. The two-month of ECMs coordination with health-related agencies according to older adults' needs, and made home visits encouraged the aged to acquire knowledge on their diseases.

Conclusion: ECMs’s coordination with health-related agencies could support the needs of those of advanced age.
Single blind, randomized study comparing clinical equivalence of Trusilk® and Mersilk® silk sutures for mucosal closure following surgical removal of mesioangular impacted mandibular third molar
Authors: Balakrishna Ramdas , Poojary Dharnappa , R Arvind , Sali Shrikanth , Moharana Ashok Kumar , TS Deepak
Published: June 2022

Background: Mesioangular impacted mandibular third molar is a common dental anomaly, for which surgical extraction is required. Post-surgery closure of mucosa reduces the prevalence of pain and other surgery-associated complications. We compared tissue reaction/inflammation after 3 and 7 days of mucosal closure with Trusilk® and Mersilk® silk sutures, following impacted mandibular third molar removal.

Methods: This multicenter, prospective, two-arm, parallel-group, randomized (1:1), single-blind study (July 2020-November 2021) included subjects (Trusilk®, n=65 and Mersilk®, n=64), requiring mucosal suturing following impacted mandibular third molar removal. The primary endpoint, incidence of pain, swelling and trismus at the extraction area on post-surgery day 3 and 7 was evaluated. The secondary endpoints, incidence of tissue reaction, wound infection, suture loosening, other complications, operative time, amount of anesthesia, intraoperative suture handling, time needed for complete wound healing and suture removal, and adverse events were also recorded.

Results: Socio-demographic and intra-oral characteristics were comparable between the groups. In Trusilk® and Mersilk® groups, a gradually decreasing pain score, starting from day 0 post-surgery (42.17±22.38 vs. 45.97±22.20) to day 7 (8.40±11.93 vs. 8.28±12.13) to day 30 (1.98±0.89 vs. 1.75±0.76) was witnessed. After the surgery, 21.54% and 17.19% subjects in Trusilk® and Mersilk® groups, respectively, had no post-operative swelling, while at the last two visits none of the subjects had swelling. Non-significant difference in wound infection, suture loosening, wound healing, bleeding, taste changes, operative time, amount of anesthesia, intraoperative suture handling, and time needed for complete wound healing and suture removal was noted among the groups. No suture-related adverse events were recorded.

Conclusions: The results indicated that the Trusilk® and Mersilk® silk sutures are clinically equivalent and can be used for mucosal closure after removal of an impacted mandibular third molar with a minimal rate of pain, swelling and trismus.

Clinical Trial Registry of India Registration: CTRI/2020/03/024100 (20/03/2020)
Introducing R as a smart version of calculators enables beginners to explore it on their own
Authors: Choudhary Krishna , Pico Alexander R.
Published: June 2022

Rapid technological advances in the past decades have enabled molecular biologists to generate large-scale and complex data with affordable resource investments, or obtain such data from public repositories. Yet, many graduate students, postdoctoral scholars, and senior researchers in the biosciences find themselves ill-equipped to analyze large-scale data. Global surveys have revealed that active researchers prefer short training workshops to fill their skill gaps. In this article, we focus on the challenge of delivering a short data analysis workshop to absolute beginners in computer programming. We propose that introducing R or other programming languages for data analysis as smart versions of calculators can help lower the communication barrier with absolute beginners. We describe this comparison with a few analogies and hope that other instructors will find them useful. We utilized these in our four-hour long training workshops involving participatory live coding, which we delivered in person and via videoconferencing. Anecdotal evidence suggests that our exposition made R programming seem easy and enabled beginners to explore it on their own.
A biopsychosocial approach to death, dying, and bereavement: a course on end-of-life education for medical students
Authors: Kripalani Simran , Joy Sandra , Raizada Shivani , Cerceo Elizabeth
Published: June 2022

Background: Despite the inevitable nature of death and dying, the conversations surrounding this subject are still uncomfortable for many physicians and medical students.

Methods: A six-week humanities-based course, “A Biopsychosocial Approach to Death, Dying, & Bereavement,” at Cooper Medical School of Rowan University, United States, which covers definitions of death and dying, the process of dying, ethical dilemmas, and new concepts of the grieving process. Through development of a curriculum using various academic and medical literature and resources, we sought to bring attention to the necessity of having a medical education curriculum on death and dying to prepare medical students for the difficult conversations and patient experiences that lie ahead of them. Qualitative data in the form of surveys and reflection papers submitted by students and quantitative data (Likert scores on course satisfaction) were collected and analyzed both pre- and post-course.

Results: 90.7% (49/54) of the respondents answered that they agree or strongly agree with the statement that this selective course was useful in the student’s medical education experience. The top three qualitative themes brought up the most in reflection papers (n=50) were: the utility and instruction of the course (23 times), the importance of hospice and palliative care (23 times), and respecting patient autonomy (16 times).

Conclusions: Medical students are often not prepared to cope with the realities of patient loss and of caring for the patient and their families throughout the dying process. We created this course to familiarize medical students with an aspect of the medical experience that is frequently neglected in traditional medical curricula. We learned that integrating such a course can help educate medical students facilitate important conversations, teach them to act with kindness and dignity in a physician-patient setting, and enhance their personal understanding of death and dying.
Blockchain-Enabled Deep-Tier Supply Chain Finance
Authors: Dong Lingxiu , Qiu Yunzhe , Xu Fasheng
Published: June 2022

Problem definition: For many supply chains, deep-tier suppliers, due to their small size and lack of access to capital, are most vulnerable to disruptions. We study the use of advance payment (AP) as a financing instrument in a multitier supply chain to mitigate the supply disruption risk in a traditional system (with limited visibility) and a blockchain-enabled system (with perfect visibility). The main goal of this paper is to shed light on how blockchain adoption impacts agents’ operational and financial decisions as well as profit levels in a multitier supply chain. Academic/practical relevance: Traditionally, because of the limited visibility in the deep tiers, powerful downstream manufacturers’ financing schemes offered to their immediate upstream suppliers are not effective in instilling capital into the deep tiers. Advancements in blockchain technology improve the supply chain visibility and enable the manufacturer to better devise deep-tier financing to improve supply chain resilience. Methodology: We develop a three-tier supply chain model and take a game-theoretic approach to compare how blockchain-enabled deep-tier financing schemes affect a financially constrained supply chain’s optimal risk-mitigation and financial strategies. Results: We find that although improved visibility via blockchain adoption can help the manufacturer make informed supply chain financing decisions, whether it can benefit all supply chain members depends on the financing schemes in use. Blockchain-enabled delegate financing increases risk-mitigation investments and benefits all three tiers of the supply chain only when the tier 2 supplier is severely capital-constrained with the working capital below a threshold. Because delegate financing endows the intermediary tier 1 supplier with leverage over the manufacturer, the inefficiency inhibits an all-win outcome when the tier 2 supplier is not severely capital-constrained. Blockchain-enabled cross-tier direct financing exhibits a compelling performance as it always leads to win-win-win outcomes (and is thus ubiquitously implementable) regardless of the suppliers’ working capital profile. Managerial implications: Our insights help firms assess opportunities and challenges associated with enhancing supply chain visibility via blockchain adoption.
The Mechanisms and Components of Knowledge Transfer: The Virtual Special Issue on Knowledge Transfer Within Organizations
Authors: Argote Linda , Guo Jerry , Park Sae-Seul , Hahl Oliver
Published: June 2022

Knowledge transfer within organizations has important implications for organizational performance and competitive advantage. In this virtual special issue, we review articles on this topic published in Organization Science between 2014 and 2020 and identify 53 articles for their theoretical and empirical contributions. These articles examine knowledge transfer through five transfer mechanisms: social networks, routines, personnel mobility, organizational design, and search. We consider the intersection of each transfer mechanism with important components of knowledge transfer (characteristics of sources/recipients, characteristics of knowledge, and characteristics of contexts). We present 15 exemplar articles, each of which reflects the intersection of a mechanism and a component of knowledge transfer. We also present an overview of the methodological approaches and empirical contexts that are utilized. We conclude our article with a discussion of future research opportunities. The articles published in Organization Science have advanced understanding of both the mechanisms through which knowledge transfer occurs and the conditions under which it is most likely.
Moderating the work distress experience among inpatient hospice staff: a qualitative study
Authors: McKenna Morgan , Dempster Martin , Jarowslawska Agnieszka , Shayegh John , Graham-Wisener Lisa , McPherson Alan , White Clare
Published: June 2022

Background: Palliative and hospice care health professionals may be at risk of poorer psychological outcomes. It is unclear what specific stressors are experienced by staff and what impact they have on their psychological wellbeing. Aims: To identify stressors experienced when working in an adult hospice inpatient unit environment and how these are managed. Methods: Individual interviews were conducted with healthcare professionals working in a hospice adult inpatient unit. Findings: A total of 19 staff were interviewed. Six themes were constructed, with four related to stressors experienced: unrealistic workload, patient care, managing relationships, and work culture. Two themes concerned strategies for managing stressors were identified: peer support and time out. Conclusion: Changes within hospice care provision are placing demands on staff and reducing the amount of available resources. This may be alleviated by a move towards more compassionate workplaces. There is a need for further research to identify how distress can best be managed and how hospice organisations can best support healthcare staff.
Diversity of Social Wasps in the Campus of the “Universidade Federal de Viçosa” in Viçosa, Minas Gerais State, Brazil
Authors: De Castro Jacques Gabriel , Zanuncio José Cola
Published: June 2022

Social wasps can be used as ecological indicators. However, the diversity of species of this group in Minas Gerais State, Brazil, is poorly studied, especially in anthropized environments. The objective was to study diversity of these insects in the campus of the “Universidade Federal de Viçosa” in Viçosa, Minas Gerais State, Brazil, from May to June 2011 with two methodologies (attractive traps and active search). Eight hundred and eighty-nine individuals of social wasps of 10 genera and 25 species were collected. The high species richness found can be explained by the diverse environment of the area studied with greater availability of microhabitats, greater protection against predators, and high availability and diversity of food and substrates for nesting which may favor the coexistence of a greater number of species. In addition, combined use of two collecting methodologies provided a greater diversity of wasps captured.
Peer-to-peer disaggregated telemetry for autonomic machine-learning-driven transceiver operation
Authors: Paolucci Francesco , Sgambelluri Andrea , Felipe Silva Moises , Pacini Alessandro , Castoldi Piero , Valcarenghi Luca , Cugini Filippo
Published: June 2022

Autonomic networking and monitoring will drive the evolution of next generation software defined networking (SDN) optical networks towards the zero touch networking paradigm. Optical telemetry services will play a key role to enable advanced network awareness at device and component granularity. Optical disaggregation is pushing the adoption of open models, enabling multi-vendor interoperability, including telemetry. Moreover, due to whitebox programmability and the adoption of open source micro services, it is becoming feasible to monitor data streams from optical devices related to quality of transmission key performance indicators. Finally, due to mature big data analytics platforms, including machine learning and artificial intelligence, the telemetry data lake is processed to effectively detect network anomalies. However, current centralized telemetry architectures are prone to scalability issues, suboptimal soft failure recovery due to operational mode limitations, and/or the inability of the SDN controller of tuning finer or proprietary transmission parameters. Conversely, a number of soft failures might be detected and recovered directly at the optical card transmitter, often in a hitless fashion, also relying on optimized vendor-proprietary configurations. The paper proposes what we believe to be a novel peer-to-peer telemetry (P2PT) service ready for next generation digital coherent optics cards, for local processing and soft failure recovery at the transceiver agent level. The P2PT architecture, workflow, and subscription extensions are conceived to enable direct and fast recovery at the transceiver level, resorting to optical signal retuning and adaptations. Experimental evaluations, including lightweight machine learning detection at the card agent, are provided in a multi-vendor disaggregated optical network testbed to assess different soft failure use cases and P2PT service scalability.
Semianalytical model of optical cavity-assisted photon–nucleon coupling
Authors: He Fei , Zhu Ka-Di
Published: June 2022

We propose a semianalytical method to evaluate photon–nucleon interaction. Our method is based on adding an optical cavity to the neutron decay process. This model is an extension of the classical Fermi’s beta decay model, which satisfactorily considers the effects of optical cavities on nuclear decay. The numerical simulation results show that this model may explain the neutron lifetime problem in the present experiment. Finally, we discuss the discrepancy in current methods of measuring neutron lifetime, which may be caused by different experimental setups.
Quantum imaging and metrology with undetected photons: tutorial
Authors: Barreto Lemos Gabriela , Lahiri Mayukh , Ramelow Sven , Lapkiewicz Radek , Plick William N.
Published: June 2022

We present a tutorial on the phenomenon of induced coherence without induced emission, and specifically its application to imaging and metrology. It is based on a striking effect where two nonlinear crystals, by sharing a coherent pump and one or two output beams, can induce coherence between the other two output beams. This can be thought of as a type of quantum-erasure effect, where the “welcher-weg” (which-way), or in this case, “which-source,” information is erased when the shared beams are aligned. With the correct geometry, this effect can allow an object to be imaged using only photons that have never interacted with the object—in other words, the image is formed using undetected photons. Interest in this and related setups has been accelerating in recent years due to a number of desirable properties, mostly centered around the fact that the fields for detection and imaging (since separate) may have different optical properties, entailing significant advantages for various applications. The purpose of this tutorial is to introduce researchers to this area of research, to provide practical tools for setting up experiments as well as understanding the underlying theory, and also to provide a comprehensive overview of the sub-field as a whole.
Machine-learning-based beam steering in a hybrid plasmonic nano-antenna array
Authors: Mahmoud Korany R. , Montaser Ahmed M.
Published: June 2022

In this paper, different beam-steering techniques are introduced using an

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hybrid plasmonic nano-antenna array operating at 1550 nm. Two conventional techniques of the switched-beam and phased array are considered for implementing beam steering. For a switched-beam antenna, the beam steering is achieved by switching between the feed antenna elements, whereas the feed antenna array is attached to the back surface of a fishnet achromatic-metalens to collimate the rays. In the phased array antenna, the beam is steered by estimating the appropriate feeding phases of the 64 elements using a deep neural network (DNN) either with or without a lens and comparing the results with those obtained using a traditional method. Finally, a hybrid technique based on activating only a subset of antenna elements in the existence of the lens is proposed to steer the pattern in a certain direction. By predicting the proper feeding phases of the antenna array elements, the neural network with the backpropagation technique and weighted hybrid gravitational search algorithm-particle swarm optimization approach is used to beam-steer the pattern. Furthermore, the DNN is applied to assign the required active subset elements for directing the main beam toward the desired direction. Several sample examples are provided to beam-steer the pattern in numerous directions to assess the correctness of the strategies.
Dephasing effect of Rydberg states on trap loss spectroscopy of cold atoms
Authors: Cao Yifei , Yang Wenguang , Zhang Hao , Jing Mingyong , Li Weibin , Zhang Linjie , Xiao Liantuan , Jia Suotang
Published: June 2022

In this paper, we investigate the asymmetry of trap loss spectra of ultracold atoms during the excitation of Rydberg states. It is shown that the profile of a trap loss spectrum is affected by the density of Rydberg atoms as well as the dephasing rate of Rydberg states. The splitting of a trap loss spectrum is shown at the higher dephasing rates of Rydberg states. A three-level model, where the dephasing rates can be ascribed mainly to a random collision of Rydberg atoms, reasonably explains the experimental results.
Dual-wavelength hybrid Tamm plasmonic laser
Authors: Shahed-E-Zumrat  , Shahid Shadman , Talukder Muhammad Anisuzzaman
Published: June 2022

Miniature lasers emitting dual-wavelength modes have diverse applications alongside the more explored single-mode counterparts. However, having dual-wavelength modes originating from a plasmonic-photonic hybrid laser is still a relatively new area for research. Compared to the amount of literature devoted to the physics of such hybrid cavities, only a few have analyzed their role in lasing applications. Notably, the role of hybrid cavities in dual-wavelength lasing is still unexplored. In this work, the properties of one-dimensional distributed Bragg reflectors and thin metal nanohole arrays come together to create a hybrid dual-mode plasmonic laser. The similar energy distribution characteristics of photonic and plasmonic lasers make hybrid structures a viable choice for efficient dual-mode lasing. In this work, the lasing cavity simultaneously excites photonic and Tamm plasmonic modes to generate dual-mode lasing. Consequently, the proposed laser shows high emission output with narrow linewidth and a clear and tunable mode separation.
Mach-Zehnder interferometer based integrated-photonic acetone sensor approaching the sub-ppm level detection limit
Authors: Niu Haoyun , Yu Peng , Zhu Yisong , Jing Zhimin , Li Peihang , Wang Baoqing , Ma Cuiping , Wang Jiaying , Wu Jiang , Govorov Alexander O. , Neogi Arup , Wang Zhiming M.
Published: June 2022

The detection of acetone in the gaseous form in exhaled breath using an integrated sensor can provide an effective tool for disease diagnostics as acetone is a marker for monitoring human metabolism. An on-chip acetone gas sensor based on the principle of Mach-Zehnder interferometer is proposed and demonstrated. The sensing arm of the device is activated with a composite film of polyethyleneimine and amido-graphene oxide as the gas-sensitive adsorption layer. The composite film demonstrates good selectivity to acetone gas, can be used repeatedly, and is stable in long-term use. Room temperature operation has been demonstrated for the sensor with high sensitivity under a 20 ppm acetone environment. The detection limit can reach 0.76 ppm, making it feasible to be used for the clinical diagnosis of diabetes and the prognosis of heart failure.
High-resolution ptychographic imaging enabled by high-speed multi-pass scanning
Authors: Deng Junjing , Yao Yudong , Jiang Yi , Chen Si , Mooney Tim M. , Klug Jeffrey A. , Marin Fabricio S. , Roehrig Christian , Yue Ke , Preissner Curt , Cai Zhonghou , Lai Barry , Vogt Stefan
Published: June 2022

As a coherent diffraction imaging technique, ptychography provides high-spatial resolution beyond Rayleigh’s criterion of the focusing optics, but it is also sensitively affected by the decoherence coming from the spatial and temporal variations in the experiment. Here we show that high-speed ptychographic data acquisition with short exposure can effectively reduce the impact from experimental variations. To reach a cumulative dose required for a given resolution, we further demonstrate that a continuous multi-pass scan via high-speed ptychography can achieve high-resolution imaging. This low-dose scan strategy is shown to be more dose-efficient, and has potential for radiation-sensitive sample studies and time-resolved imaging.
Atomic-scale mapper for superlattice photodetectors analysis
Authors: Bidenko Pavlo , Ahn Seungyeop , Kang Ko-ku , Lee Hyun-jin , Kim Young Ho , Kim SangHyeon
Published: June 2022

In this work, a new Python-based tool for atomic-scale mapping of high-angle annular dark-field (HAADF) and annular bright-field (ABF) scanning transmission electron microscopy (STEM) images using the Z-contrast method is introduced, aimed to help in the analysis of superlattice layers’ composition, and in the determination of material of interfaces. The operation principle of the program, as well as specific examples of use, are explained in many details. Good customization flexibility using the user-friendly graphical user interface (GUI), allows the processing of a wide range of images, demonstrating a decent accuracy of coordinates extraction and performance.
Silicon photonic olfactory sensor based on an array of 64 biofunctionalized Mach-Zehnder interferometers
Authors: Laplatine Loic , Fournier Maryse , Gaignebet Nicolas , Hou Yanxia , Mathey Raphael , Herrier Cyril , Liu Jie , Descloux Delphine , Gautheron Bertrand , Livache Thierry
Published: June 2022

Silicon photonics can address a variety of applications, from datacom and biosensing to lidars. Recently, this technology has been explored for gas sensing. Detection and identification of odors remains a critical challenge in diverse areas such as air quality, food spoilage, or personal well-being. In this work, we present an olfactory sensor based on an array of 64 biofunctionalized Mach-Zehnder interferometers integrated on a silicon nitride platform. The ability to analyze odors at ppm level is demonstrated for several volatile organic compounds.
Impedance matching via ultrathin metatronic layer assisted by Smith Chart
Authors: Sun Wangyu , Qin Xu , Li Hao , Zhou Ziheng , Li Yue
Published: June 2022

Metatronics, as a feasible paradigm of nanocircuits using effective electronic elements (e.g., nanocapacitors, nanoinductors, and nanoresistors), provides the possibility for light manipulation in subwavelength scales assisted by the circuit-related technologies in electronics. As a representative technique in electronics, Smith Chart provides a fast, less-computation and graphical approach to solve the problems related to impedance matching. Here, we transplant the Smith Chart into the paradigm of optical metatronics to develop an analytical approach for impedance matching for light propagation and coined the name of graphical metatronics. In this approach, the impedance characteristics of four basic types of ultrathin metatronic layers are creatively mapped into each rotation trace on the complex Γ mathematical plane (Γ means the reflection coefficient). The impedance matching problems can be graphically solved by searching for feasible rotation traces on the Γ plane without full-wave simulations. Based on this approach, various applications related to impedance matching (e.g., antireflection coating, perfect transmission, absorber, etc.) are developed analytically and validated by numerical results. The proposed approach constructs the bridge among Smith Chart, plasmonics and photonics, providing a fast, visualized and less-computation route and guideline to develop various nanophotonic structures and devices for impedance-matching applications.
Enormous electro-optic effect in paraelectric nanodisordered KTa1-xNbxO3 crystal
Authors: Zhang JianWei , Du XaioPing , Zhao JiGuang , Wang XuPing , Liu Bing , Song YiShuo , Liu ZhengJun , Chen Hang
Published: June 2022

Recent experiments have revealed that the order of the electro-optic
(EO) effect depends on the frequency of electric field in paraelectric
nanodisordered KTa1-xNb
x
O3 (KTN) crystal. Through the
dielectric frequency spectrum under the bias electric field, enormous
linear and quadratic EO effects were discovered at the resonance
frequencies, which changed the perception that only the quadratic EO
effect exists. Applying just a small AC electric field of 6 V/mm, the
effective linear EO coefficient reached 478 pm/V at 609 kHz, and the
effective quadratic EO coefficient reached
4.39*10−13m2V−2at 302 kHz. The reason
why an extremely low electric field results in an enormous EO
coefficient is attributed to the resonance between the polar
nanoregions (PNRs) and the electric field, induced by the field-driven
reorientation of free dipoles on the boundary of the PNRs. In
addition, the order of EO effect depending on the frequency of
electric field was attributed to the motion modes of the PNR. This
finding improves the understanding of how the EO effect is caused by
field-driven PNR dynamics, but also provides a basis for the
development of EO devices.
Local dielectric tunnel junction to manage the current distribution for AlGaN-based deep-ultraviolet light-emitting diodes with a thin p-GaN layer
Authors: Li Qingqing , Chu Chunshuang , Wang Weidong , Che Jiamang , Shao Hua , Liu Qianqian , Zhang Yonghui , Zhang Zi-hui
Published: June 2022

In this report, a p+-GaN/SiO2/Ni tunnel junction with a local SiO2 insulation layer is designed to manage the current distribution for commercially structured AlGaN-based deep-ultraviolet light-emitting diodes (DUV LEDs) with a thin p-GaN layer. The experimental and calculated results prove that, besides the increased hole injection at the p+-GaN/SiO2/Ni tunnel junction, the local SiO2 layer produces an in-plane unbalanced energy band in the p-GaN layer for the proposed DUV LEDs, thus modulating the carrier transport paths and increasing the spread of holes. Enhanced optical power is obtained when compared to conventional DUV LEDs. In addition, the influence of the position of the SiO2 insulation layer on the current distribution is also investigated in this work. Placing the SiO2 insulation layer in the middle position of the p+-GaN layer is most helpful for increasing the hole injection efficiency for commercially structured DUV LEDs.
Pulse-width-dependent critical power for self-focusing of ultrashort laser pulses in bulk dielectrics
Authors: Kudryashov S. I. , Danilov P. A. , Kuzmin E. V. , Gulina Yu. S. , Rupasov A. E. , Krasin G. K. , Zubarev I. G. , Levchenko A. O. , Kovalev M. S. , Pakholchuk P. P. , Ostrikov S. A. , Ionin A. A.
Published: June 2022

Microscale filamentation of 0.25 NA-focused, linearly and circularly polarized 1030 nm and 515 nm ultrashort laser pulses of variable pulse widths in fused silica, fluorite, and natural and synthetic diamonds demonstrates the Raman–Kerr effect in the form of critical pulse power magnitudes, proportional to squared wavelength and inversely proportional to laser pulse width of 0.3–10 ps. The first trend represents the common spectral relationship between the quantities, while the second indicates its time-integrated inertial contribution of Raman-active lattice polarization, appearing in transmission spectra via ultrafast optical-phonon Raman scattering. The optical-phonon contribution to the nonlinear polarization could come from laser field-induced spontaneous/stimulated Raman scattering and coherent optical phonons generated by electron–hole plasma with its clamped density in the nonlinear focus. Almost constant product value of the (sub)picosecond laser pulse widths and corresponding critical pulse powers for self-focusing and filamentation in the dielectrics (“critical pulse energy”) apparently implies constant magnitude of the nonlinear polarization and other “clamped” filamentation parameters at the given wavelength.
Mode-locking induced by coherent driving in fiber lasers
Authors: Mas Arabí Carlos , Englebert Nicolas , Parra-Rivas Pedro , Gorza Simon-Pierre , Leo François
Published: June 2022

Mode-locking is a broad concept that encompasses different processes enabling short optical pulse formation in lasers. It typically requires an intracavity mechanism that discriminates between single and collective mode lasing, which can be complex and sometimes adds noise. Moreover, known mode-locking schemes do not guarantee phase stability of the carrier wave. Here, we theoretically propose that injecting a detuned signal seamlessly leads to mode-locking in fiber lasers. We show that phase-locked pulses, akin to cavity solitons, exist in a wide range of parameters. In that regime the laser behaves as a passive resonator due to the non-instantaneous gain saturation.
Demonstration of turbulence mitigation in a 200-Gbit/s orbital-angular-momentum multiplexed free-space optical link using simple power measurements for determining the modal crosstalk matrix
Authors: Hu Nanzhe , Song Haoqian , Zhang Runzhou , Zhou Huibin , Liu Cong , Su Xinzhou , Song Hao , Pang Kai , Zou Kaiheng , Lynn Brittany , Tur Moshe , Willner Alan E.
Published: June 2022

We experimentally demonstrate turbulence mitigation in a 200-Gbit/s quadrature phase-shift keying (QPSK) orbital-angular-momentum (OAM) mode-multiplexed system using simple power measurements for determining the modal coupling matrix. To probe and mitigate turbulence, we perform the following: (i) sequentially transmit multiple probe beams at 1550-nm wavelength each with a different combination of Laguerre–Gaussian (LG) modes; (ii) detect the power coupling of each probe beam to
L

G
0,0 for determining the complex modal coupling matrix; (iii) calculate the conjugate phase of turbulence-induced spatial phase distortion; (iv) apply this conjugate phase to a spatial light modulator (SLM) at the receiver to mitigate the turbulence distortion for the 1552-nm mode-multiplexed data-carrying beams. The probe wavelength is close enough to the data wavelength such that it experiences similar turbulence, but is far enough away such that the probe beams do not affect the data beams and can all operate simultaneously. Our experimental results show that with our turbulence mitigation approach the following occur: (a) the inter-channel crosstalk is reduced by ∼25 and ∼21 dB for OAM +1 and −2 channels, respectively; (b) the optical signal-to-noise ratio (OSNR) penalty is <1 dB for both OAM channels for a bit error rate (BER) at the 7% forward error correction (FEC) limit, compared with the no turbulence case.
Tunable and efficient near-infrared plasmonic interconnect circuit based on an index matching layer and a metal reflector
Authors: Zhang Canran , Wu Zhipeng , Wang Qilong
Published: June 2022

The plasmonic interconnect circuit (PIC) has shown great application prospects in chip-level optoelectronic systems. In this paper, we focus on a class of on-chip PIC based on a subwavelength metal grating coupler and decoupler. We systematically study the effect of grating depth on the coupling and decoupling efficiency of the designed device. The energy utilization of the device can be greatly improved and the device footprint has been reduced by about 30% at the same time by using an index matching layer. The optimal operating point of the device is finally stabilized around 1310 nm by adjusting the refractive index of the top matching layer and introducing the bottom metal reflector. The coupling and decoupling efficiency of the optimized device can reach 38% and 18% respectively and can be future adjusted linearly and synchronously by changing the refractive index of the matching layer. Our work provides an efficient and easily-fabricated PIC platform and gives the possibility to realize tunable on-chip plasmonic interconnection.
Neural circuit mechanisms of hierarchical sequence learning tested on large-scale recording data
Authors: Asabuki Toshitake , Kokate Prajakta , Fukai Tomoki
Published: June 2022

The brain performs various cognitive functions by learning the spatiotemporal salient features of the environment. This learning requires unsupervised segmentation of hierarchically organized spike sequences, but the underlying neural mechanism is only poorly understood. Here, we show that a recurrent gated network of neurons with dendrites can efficiently solve difficult segmentation tasks. In this model, multiplicative recurrent connections learn a context-dependent gating of dendro-somatic information transfers to minimize error in the prediction of somatic responses by the dendrites. Consequently, these connections filter the redundant input features represented by the dendrites but unnecessary in the given context. The model was tested on both synthetic and real neural data. In particular, the model was successful for segmenting multiple cell assemblies repeating in large-scale calcium imaging data containing thousands of cortical neurons. Our results suggest that recurrent gating of dendro-somatic signal transfers is crucial for cortical learning of context-dependent segmentation tasks.
Dync1li1 is required for the survival of mammalian cochlear hair cells by regulating the transportation of autophagosomes
Authors: Zhang Yuan , Zhang Shasha , Zhou Han , Ma Xiangyu , Wu Leilei , Tian Mengyao , Li Siyu , Qian Xiaoyun , Gao Xia , Chai Renjie
Published: June 2022

Dync1li1, a subunit of cytoplasmic dynein 1, is reported to play important roles in intracellular retrograde transport in many tissues. However, the roles of Dync1li1 in the mammalian cochlea remain uninvestigated. Here we first studied the expression pattern of Dync1li1 in the mouse cochlea and found that Dync1li1 is highly expressed in hair cells (HCs) in both neonatal and adult mice cochlea. Next, we used Dync1li1 knockout (KO) mice to investigate its effects on hearing and found that deletion of Dync1li1 leads to early onset of progressive HC loss via apoptosis and to subsequent hearing loss. Further studies revealed that loss of Dync1li1 destabilizes dynein and alters the normal function of dynein. In addition, Dync1li1 KO results in a thinner Golgi apparatus and the accumulation of LC3+ autophagic vacuoles, which triggers HC apoptosis. We also knocked down Dync1li1 in the OC1 cells and found that the number of autophagosomes were significantly increased while the number of autolysosomes were decreased, which suggested that Dync1li1 knockdown leads to impaired transportation of autophagosomes to lysosomes and therefore the accumulation of autophagosomes results in HC apoptosis. Our findings demonstrate that Dync1li1 plays important roles in HC survival through the regulation of autophagosome transportation.