bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk and Outcome of Breakthrough COVID-19 Infections in Vaccinated Patients With Cancer: Real-World Evidence From the National COVID Cohort Collaborative
Authors: Song Qianqian , Bates Benjamin , Shao Yu Raymond , Hsu Fang-Chi , Liu Feifan , Madhira Vithal , Mitra Amit Kumar , Bergquist Timothy , Kavuluru Ramakanth , Li Xiaochun , Sharafeldin Noha , Su Jing , Topaloglu Umit
Published: March 2022

PURPOSE

To provide real-world evidence on risks and outcomes of breakthrough COVID-19 infections in vaccinated patients with cancer using the largest national cohort of COVID-19 cases and controls.

METHODS

We used the National COVID Cohort Collaborative (N3C) to identify breakthrough infections between December 1, 2020, and May 31, 2021. We included patients partially or fully vaccinated with mRNA COVID-19 vaccines with no prior SARS-CoV-2 infection record. Risks for breakthrough infection and severe outcomes were analyzed using logistic regression.

RESULTS

A total of 6,860 breakthrough cases were identified within the N3C-vaccinated population, among whom 1,460 (21.3%) were patients with cancer. Solid tumors and hematologic malignancies had significantly higher risks for breakthrough infection (odds ratios [ORs] = 1.12, 95% CI, 1.01 to 1.23 and 4.64, 95% CI, 3.98 to 5.38) and severe outcomes (ORs = 1.33, 95% CI, 1.09 to 1.62 and 1.45, 95% CI, 1.08 to 1.95) compared with noncancer patients, adjusting for age, sex, race/ethnicity, smoking status, vaccine type, and vaccination date. Compared with solid tumors, hematologic malignancies were at increased risk for breakthrough infections (adjusted OR ranged from 2.07 for lymphoma to 7.25 for lymphoid leukemia). Breakthrough risk was reduced after the second vaccine dose for all cancers (OR = 0.04; 95% CI, 0.04 to 0.05), and for Moderna's mRNA-1273 compared with Pfizer's BNT162b2 vaccine (OR = 0.66; 95% CI, 0.62 to 0.70), particularly in patients with multiple myeloma (OR = 0.35; 95% CI, 0.15 to 0.72). Medications with major immunosuppressive effects and bone marrow transplantation were strongly associated with breakthrough risk among the vaccinated population.

CONCLUSION

Real-world evidence shows that patients with cancer, especially hematologic malignancies, are at higher risk for developing breakthrough infections and severe outcomes. Patients with vaccination were at markedly decreased risk for breakthrough infections. Further work is needed to assess boosters and new SARS-CoV-2 variants.
Current Management of Locally Advanced and Metastatic Cervical Cancer in the United States
Authors: Pang Shiyi Sarah , Murphy Martina , Markham Merry J.
Published: March 2022

Despite decreases in incidence in the twentieth century, cervical cancer continues to be a highly morbid disease in the United States. For those diagnosed with locally advanced disease, single-agent cisplatin-based chemotherapy concurrent with radiation remains the mainstay of treatment. For patients with metastatic, progressive, and recurrent disease, treatment typically consists of combination chemotherapy and incorporation of bevacizumab, and recent data show benefits with the addition of upfront immunotherapy in women whose cancer expresses programmed death ligand-1. The physical sequelae of locally advanced cervical cancer treatments stem largely from irradiation of the pelvis, and treatment of these is aimed at identifying reversible or treatable causes of symptoms and palliating those with irreversible causes. From a psychologic standpoint, patients with cervical cancer face the stigma of having a preventable cancer caused by a sexually transmitted infection and the ramifications of sexual dysfunction. Clinicians must invite honest dialogue to be able to address specific survivorship issues.
Postoperative Ketoacidosis With Hypoglycemia in a Nondiabetic Patient Taking Dapagliflozin for Heart Failure: A Case Report
Authors: Seki Hiroyuki , Watanabe Hidenobu , Yorozu Tomoko
Published: March 2022

Sodium-glucose cotransporter 2 (SGLT-2) inhibitors are relatively new antidiabetic drugs, which have been recently approved for heart failure treatment. Although treatment interruption is recommended 3 to 4 days before surgery, it is unclear whether SGLT-2 inhibitors should be discontinued when prescribed for heart failure treatment. We describe a case of postoperative ketoacidosis with hypoglycemia in an 83-year-old woman who took dapagliflozin for heart failure and underwent transcatheter aortic valve replacement. She was nondiabetic and took dapagliflozin on the day of the procedure. This case suggests the need to discontinue SGLT-2 inhibitors ahead of the day of surgery when used for heart failure.
Network analysis reveals that acute stress exacerbates gene regulatory responses of the gill to seawater in Atlantic salmon
Authors: Monette Michelle Y. , Velotta Jonathan P.
Published: March 2022

The transition from freshwater to seawater represents a physiological challenge for Atlantic salmon smolts preparing for downstream migration. Stressors occurring during downstream migration to the ocean impair the ability of smolts to maintain osmotic/ionic homeostasis in seawater. The molecular mechanisms underlying this interaction are not fully understood, especially at the organ-level. We combined RNA-seq with measures of whole animal homeostasis to examine gene expression dynamics in the gills of smolts associated with impaired seawater tolerance after an aquaculture-related stressor. Smolts were given a 24 h seawater tolerance test before and after exposure to an acute handling/confinement stress. RNA-seq followed by Differential Expression and Weighted Gene Correlation Network Analysis (WGCNA) was used to quantify the transcriptional response of the gill to handling/confinement stress, seawater, and their interaction. Exposure to acute stress was associated with a general stress response and impaired osmotic/ionic homeostasis in seawater. We identified gene networks in the gill exhibiting response to acute stress alone, seawater alone, and others exhibiting combined effects of both stress and seawater. Our findings indicate that acute handling/confinement stress increases the intensity of seawater-related gene expression and suggest that increased investment in mechanisms related to ion transport may be part of a compensatory response to impaired seawater tolerance in smolts.
Artificial intelligence can detect left ventricular dilatation on contrast-enhanced thoracic computer tomography relative to cardiac magnetic resonance imaging
Authors: Asif Ashar , Charters Pia F. P. , Thompson Charlotte A. S. , Komber Hend M. E. I. , Hudson Benjamin J. , Rodrigues Jonathan Carl Luis
Published: March 2022

Objectives:

To assess the diagnostic accuracy of an automated algorithm to detect left ventricular (LV) dilatation on non-ECG gated CT, using cardiac magnetic resonance (CMR) as reference standard.

Methods

Consecutive patients with contrast-enhanced CT thorax and CMR within 31 days (2016–2020) were analysed (n = 84). LV dilatation was defined against age-, sex- and body surface area-specific values for CMR. CTs underwent automated artificial intelligence(AI)-derived analysis that segmented ventricular chambers, presenting maximal LV diameter and volume. Area under the receiver operator curve (AUC-ROC) analysis identified CT thresholds with ≥90% sensitivity and highest specificity and ≥90% specificity with highest sensitivity. Youden’s Index was used to identify thresholds with optimised sensitivity and specificity.

Results:

Automated diameter analysis was feasible in 92% of cases (77/84; 45 men, age 61 ± 14 years, mean CT to CMR interval 10 ± 8 days). Relative to CMR as a reference standard, 45% had LV dilatation. In males, an automated LV diameter measurement of ≥55.5 mm was ≥90% specific for CMR-defined LV dilatation (positive predictive value (PPV) 85.7%, negative predictive value (NPV) 61.2%, accuracy 68.9%). In females, an LV diameter of ≥49.7 mm was ≥90% specific for CMR-defined LV dilatation (PPV 66.7%, NPV 73.1%, accuracy 71.9%). AI CT volumetry data did not significantly improve AUC performance.

Conclusion:

Fully automated AI-derived analysis LV dilatation on routine unselected non-gated contrast-enhanced CT thorax studies is feasible. We have defined thresholds for the detection of LV dilatation on CT relative to CMR, which could be used to routinely screen for dilated cardiomyopathy at the time of CT.

Advances in knowledge:

We show, for the first time, that a fully-automated AI-derived analysis of maximal LV chamber axial diameter on non-ECG-gated thoracic CT is feasible in unselected real-world cases and that the derived measures can predict LV dilatation relative to cardiac magnetic resonance imaging, the non-invasive reference standard for determining cardiac chamber size. We have derived sex-specific cut-off values to screen for LV dilatation on routine contrast-enhanced thoracic CT. Future work should validate these thresholds and determine if technology can alter clinical outcomes in a cost-effective manner.
Η επαναφοίτηση παιδιών προσχολικής ηλικίας με Διαταραχές Αυτιστικού Φάσματος στο νηπιαγωγείο ως παράγοντας επίδρασης στο γνωστικό και κοινωνικό τους τομέα
Authors: Λουκέρης Στέφανος
Published: March 2022

Στην Ελλάδα τα τελευταία χρόνια, έχει αυξηθεί σημαντικά ο αριθμός των αιτήσεων των γονέων που ζητούν την επαναφοίτηση του παιδιού τους στο νηπιαγωγείο. Η επαναφοίτηση νηπίων είναι μια συνηθισμένη πρακτική προκειμένου οι μαθητές να αποκτήσουν την απαραίτητη «σχολική ετοιμότητα» για το δημοτικό σχολείο. Η συγκεκριμένη πρακτική χρησιμοποιείται και για μαθητές με Δ.Α.Φ. αν και δεν υπάρχουν επαρκή ερευνητικά δεδομένα για τα αποτελέσματα της επαναφοίτησης σε αυτή την ομάδα μαθητών. Η παρούσα έρευνα μελετάει τα αποτελέσματα της επαναφοίτησης 102 νηπίων με Δ.Α.Φ. στον κοινωνικό και γνωστικό τους τομέα. Από την επεξεργασία και ανάλυση των δεδομένων φάνηκε ότι η επαναφοίτηση λειτουργεί θετικά τόσο στο γνωστικό όσο και στον κοινωνικό τομέα των μαθητών με Δ.Α.Φ.. Κατά τη διάρκεια της επαναφοίτησης σημαντικό ρόλο παίζουν και άλλες παράμετροι, οι οποίες δεν βρίσκονται αποκλειστικά στο σχολικό χώρο. Μερικές από αυτές τις παραμέτρους είναι τα εξωσχολικά απογευματινά υποστηρικτικά προγράμματα, το μορφωτικό επίπεδο της οικογένειας και το οικογενειακό περιβάλλον των μαθητών. Σημαντικό ρόλο φαίνεται να λαμβάνει και η συνεργασία των εκπαιδευτικών του σχολείου με τους εκπαιδευτές των υποστηρικτικών προγραμμάτων των μαθητών. Συνεπώς, η επαναφοίτηση μπορεί να έχει θετικά αποτελέσματα όταν πραγματοποιείται υπό συγκεκριμένες προϋποθέσεις εντός υποστηρικτικού πλαισίου, ενώ παράλληλα διατυπώνεται η άποψη για τη διατήρηση επιφυλάξεων όσον αφορά την επιφερόμενη βελτίωση και τους αλληλεπιδραστικούς παράγοντες που προαναφέρθηκαν.Τέλος, η παρούσα έρευνα μπορεί να αποτελέσει την κινητήριο δύναμη και για άλλους μελλοντικούς ερευνητές, ιδιαίτερα στον ελληνικό χώρο, προκειμένου να επεκτείνουν τα ευρήματα της και να αναζητήσουν ακόμη πιο στοχευμένα τις κατάλληλες συνθήκες προκειμένου η επαναφοίτηση να είναι επωφελής για τους μαθητές με Δ.Α.Φ..
Accounting of Rental Operations in the New Conditions
Authors: Kochinev Yuriy , Neelova Natalia
Published: March 2022

The article analyzes the issues of accounting for lease transactions in accordance with the FSBU 25/2018 "Lease Accounting" that came into force on 01.01.2022. Accounting for assets and liabilities subject to recognition and evaluation by both the lessor and the lessee is considered. A number of examples of accounting for rent from the lessor and lessee when transferring ownership of the lease to the lessee and when returning the leased object to the lessor are given. Recommendations are proposed to auditors auditing the financial statements of participants in rental relations.
Has the COVID-19 pandemic led to permanent persistent changes in recreational activity? A case study of a municipal beach
Authors: Senetra Adam , Szczepańska Agnieszka
Published: March 2022

Recreational areas in cities deliver numerous social, health and environmental benefits for local communities. They are a desirable element of the urban structure that influences the quality of life. The response to the COVID-19 pandemic, an unprecedented health crisis on a global scale, initially prevented and then significantly limited the use of recreational areas. The pandemic decreased daily activity levels, induced changes in lifestyle and significantly compromised people’s ability to engage in outdoor recreation. In the process of lifting lockdown restrictions, recreational areas play a special role in combatting the consequences of social isolation and restoring access to public spaces. The present study was undertaken to assess the recreational activities of urban dwellers during the COVID-19 crisis. The pandemic’s effect on the leisure behaviour of residents in the Polish city of Olsztyn was evaluated on the example of a sports and recreational centre on Lake Ukiel. The visitor traffic register and the centre’s financial performance were analysed, and a diagnostic survey targeting local residents was conducted online. The results point to a clear decline in the local community’s recreational activities as well as changes in the form and place of recreation.
Urban growth models and calibration methods: a case study of Athens, Greece
Authors: Tsagkis Pavlos
Published: March 2022

A number of urban growth models have been developed to simulate and predict urban expansion. Most of these models have common objectives; however, they differ in terms of calibration and execution methodologies. GIS spatial computations and data processing capabilities have given us the ability to draw more effective simulation results for increasingly complex scenarios. In this paper, we apply and evaluate a methodology to create a hybrid cellular-automaton- (CA) and agent-based model (ABM) using raster and vector data from the Urban Atlas project as well as other open data sources. We also present and evaluate three different methods to calibrate and evaluate the model. The model has been applied and evaluated by a case study on the city of Athens, Greece. However, it has been designed and developed with the aim of being applicable to any city available in the Urban Atlas project.
Using Theory of Change to evaluate the role of stakeholder engagement towards socially desirable outcomes in ICT research projects
Authors: Jiya Tilimbe
Published: March 2022

Information Communication Technologies (ICT) research projects are important in generating breakthrough technologies that translate into solutions for numerous societal grand challenges through research and innovation (R&I). However, to ensure that such solutions are socially desirable, there is a concerted drive for the engagement of different stakeholders, including industry, academia, public and government. In the face of the growing recognition of stakeholder engagement in ICT research projects, particularly as part of Responsible Research and Innovation (RRI), there is a limited discourse on how its consequence could be evaluated. This paper suggests and uses a Theory of Change approach to evaluate the value of stakeholder engagement on the attainment of socially desirable and responsible outcomes in projects, particularly ICT research projects. Using a multi-case study approach, the paper appraises the value of stakeholder engagement in ICT research projects by elucidating the linkages between stakeholder activities and socially desirable outcomes. The findings from the paper could apply to other types of projects apart from ICT research projects in understanding some of the roles stakeholders play in ensuring responsible innovation as an outcome of the projects.
Exact Solution Algorithms for the Chordless Cycle Problem
Authors: Pereira Dilson Lucas , Lucena Abilio , Salles da Cunha Alexandre , Simonetti Luidi
Published: March 2022

A formulation, a heuristic, and branch-and-cut algorithms are investigated for the chordless cycle problem. This is the problem of finding a largest simple cycle for a given graph so that no edge between nonimmediately subsequent cycle vertices is contained in the graph. Leaving aside procedures based on complete enumeration, no previous exact solution algorithm appears to exist for the problem, which is relevant both in theoretical and practical terms. Extensive computational results are reported here for randomly generated graphs and for graphs originating from the literature. Under acceptable CPU times, certified optimal solutions are presented for graphs with as many as 100 vertices.

Summary of Contribution: Finding chordless cycles of a graph, also known as holes, is relevant, among others, to graph theory, to the design of polyhedral based exact solution algorithms to integer programming (IP) problems, and to the practical applications that benefit from these algorithms. For instance, perfect graphs do not contain odd holes. Additionally, odd hole inequalities are valid for strengthening the formulations to numerous problems that are directly defined over graphs. Furthermore, these inequalites, in association with applicable conflict graphs, are used by all modern IP solvers to preprocess and strengthen virtually any IP formulation submitted to them.
Writing More Compelling Creative Appeals: A Deep Learning-Based Approach
Authors: Hong Jiyeon , Hoban Paul R.
Published: March 2022

In this paper, we present a deep learning-based decision support tool to assist individuals in writing effective creative appeals.
The Hidden Cost of Worker Turnover: Attributing Product Reliability to the Turnover of Factory Workers
Authors: Moon Ken , Loyalka Prashant , Bergemann Patrick , Cohen Joshua
Published: March 2022

Product reliability is a key concern for manufacturers. We examine worker turnover as a significant but underrecognized determinant of product reliability. Our study collects and integrates (1) data reporting factory worker staffing and turnover from within a major consumer electronics producer’s supply chain and (2) traceable data reporting the component quality and field failures—that is, replacements and repairs—of nearly 50 million consumer mobile devices over four years of customer usage. Devices are individually traced back to the factory conditions and staffing, down to the assembly line–week, under which they were produced. Despite the manufacturer’s extensive quality control efforts, including stringent testing, each percentage point increase in the weekly rate of workers quitting from an assembly line (its weekly worker turnover) is found to increase field failures by 0.74%–0.79%. In the high-turnover weeks following paydays, eventual field failures are strikingly 10.2% more common than for devices produced during the lowest turnover weeks immediately before paydays. In other weeks, the assembly lines experiencing higher turnover produce an estimated 2%–3% more field failures on average. The associated costs amount to hundreds of millions of U.S. dollars. We demonstrate that staffing and retaining a stable factory workforce critically underlies product reliability and showcase the value of traceability coupled with connected workplace and product data in supply chain operations.

This paper was accepted by Charles Corbett, operations management.
Global Disaster Risk Matters
Authors: Chen Jian , Yao Jiaquan , Zhang Qunzi , Zhu Xiaoneng
Published: March 2022

This article examines the cross-country asset pricing implications of disaster risk concerns. We construct a new disaster risk index, relying on six news-implied rare disaster proxies of Manela and Moreira (2017) , and show that this index is a powerful predictor for stock returns and other asset returns in international markets both in and out of sample. By further disentangling a global common component from our rare disaster index, we find evidence supporting theories that emphasize globally shared disaster risk as the important driving force of asset price fluctuations. Moreover, we conduct a return decomposition analysis and find that the global disaster risk drives stock returns primarily through the discount rate channel.

This paper was accepted by Karl Diether, finance.

Funding: This work was supported by National Natural Science Foundation of China [72132002, 71903112, 72192842, U1811462, and 71502152], the Basic Scientific Center of National Science Foundation of China [71988101], the National Social Science Foundation [21&ZD088 and 20&ZD102], SIIFE [2018110262], and the Shanghai University of Finance and Economics [2018110698].

Supplemental Material: The data files and e-companion are available at https://doi.org/10.1287/mnsc.2022.4328 .
Understanding Alpha Decay
Authors: Pénasse Julien
Published: March 2022

I study the importance of alpha decay for the measurement of realized and conditional expected returns in asset pricing studies. Alpha decay refers to the reduction in abnormal expected returns (relative to an asset pricing model) in response to an anomaly becoming widely known among market participants. As decreases in alpha are associated (ceteris paribus) with positive realized returns, the econometrician may misinterpret these repricing returns as evidence that the anomaly will persist in the future. Because alpha decay is generally a nonstationary phenomenon, asset pricing tests that impose stationarity may lead to biased inference. I illustrate the importance of alpha decay using the most commonly studied anomalies in the asset pricing literature and find that the measured alpha differs from the true alpha by about 1.4% per year. I provide a simple formula to correct for this bias and show how to incorporate alpha decay tests into the standard asset pricing toolkit.

This paper was accepted by David Simchi-Levi, finance.
Talon Cusp Management: A Case Series
Authors: Butt Razia , Aspinall Andrea , Tanday Ajit , Brown Catriona J
Published: March 2022

Talon cusps are well-defined additional cusps on the palatal or labial surface of an anterior incisor. They typically extend half the distance from the cemento-enamel junction to the incisal edge and are primarily composed of enamel and dentine with varying degrees of pulpal involvement. Talon cusps can cause clinical problems such as caries, pulpal pathology and aesthetic concerns. This case series details the management of three cases involving complete removal of the talon cusps followed by partial pulpotomy. Follow up, ranging from 6 to 24 months, showed affected teeth responded positively to sensibility testing with no clinical symptoms or radiographic changes.

CPD/Clinical Relevance: Management of talon cusps may require a multidisciplinary team approach.
Acromegaly and Dentistry: A Review
Authors: Brown Timothy , Anderson William , Keys William
Published: March 2022

Acromegaly is a progressive, multi-system disease caused by excessive growth hormone production that, if untreated, may lead to significant morbidity, mortality and impact on a sufferer's quality of life. Changes to the orofacial complex are a prominent feature of the disease, meaning the dental profession is in a unique position to be able to recognize the condition early. This article discusses its presentation, diagnosis and management with a particular focus on the potential effects on the orofacial complex, leading to an exploration of the difficulties that may be encountered when dental rehabilitation is required.

CPD/Clinical Relevance: Dental professionals may be the first to recognize the orofacial changes associated with acromegaly.
Descending Necrotizing Mediastinitis: A Potential Consequence of Odontogenic Infection
Authors: Walshaw Emma G , Taylor Richard , Parmar Jiten
Published: March 2022

Descending necrotizing mediastinitis is a potential consequence of cervicofacial infection, which can promptly progress into a life-threatening disease, with the sequelae of severe sepsis, organ failure and death. This article highlights the importance of this pathology and discusses key signs and symptoms that may be identified when performing an assessment on a patient with a large cervicofacial swelling. This article also describes the case of a young and healthy patient who experienced this pathology from an odontogenic source.

CPD/Clinical Relevance: Descending necrotizing mediastinitis, although rare, is a potentially life threatening consequence of odontogenic infection and awareness of it is imperative for dental professionals.
Optical characterization of disordered Yb-doped silica glass Anderson localizing optical fiber
Authors: Bassett Cody , Tuggle Matthew , Ballato John , Mafi Arash
Published: March 2022

We investigate and report the optical and laser characteristics of a
ytterbium-doped transverse Anderson localizing optical fiber to
develop a fundamental understanding of the light propagation,
generation, and amplification processes in this novel fiber.
Ultimately, the goal based on the measurements and calculations
conducted herein is to design and build a random fiber laser with a
highly directional beam. The measurements are based on certain
observations of the laser pump propagation and amplified spontaneous
emission generation in this fiber. Judicious approximations are used
in the propagation equations to obtain the relevant desired parameters
in simple theoretical fits to experimental observations, without
resorting to speculations based on the intended construction from the
fiber preform.
Engineering rainbow trapping and releasing in valley photonic crystal with electro-optical material
Authors: Mao Yu , Hu Weipeng , Li Zhongfu , Dai Xiaoyu , Xiang Yuanjiang
Published: March 2022

Topological photonic insulators provide a robust platform for controlling the flow of light. Here, we propose a method to realize slow light rainbow trapping and releasing based on valley photonic crystals, which is created by gradually increasing the structure parameter. The edge waves of different frequencies are spatially separated and trapped at different positions to form topological rainbow trapping. Furthermore, the system is constructed by electric-optical material whose refractive index is tuned by applied voltages. Therefore, the switchable between slow light trapping states and releasing states can be realized by tuning the external voltage. The position where the wave stops propagating is given by theoretical analysis and numerical simulation. These results offer a novel, to the best of our knowledge, scheme for realizing multi-frequency routing. Such a structure could find application prospects in optical buffers, optical storage, and other optical communication devices.
56-Gb/s/λ C-band DSB IM/DD PAM-4 40-km SSMF transmission employing a multiplier-free MLSE equalizer
Authors: Chen Zhuo , Nie Junyuan , Zhang Shenmao , Yang Qi , Dai Xiaoxiao , Deng Lei , Cheng Mengfan , Liu Deming
Published: March 2022

Chromatic dispersion, which introduces pattern-dependent inter-symbol interference (ISI), appears to be a long-standing performance limiting problem in optical intensity modulation direct detection (IM/DD) transmission systems. In this paper, we propose a multiplier-free maximum likelihood sequence estimation (MLSE) equalizer for C-band double-sideband IM/DD transmission. It models the IM/DD channel with dispersion-induced ISI and Gaussian noise. A look-up table is applied to record ISI for transition probability calculation and the Viterbi algorithm for decision sequence acquisition. Specifically, to reduce the number of multipliers, a refined construction of Viterbi algorithm based on tentative path decisions is adopted, which compresses the complexity of branch metric calculation to less than 1/4 for PAM-4 format. Moreover, approximation calculation is employed to realize multiplier-free hardware implementation, which greatly reduces the hardware consumption. The proposed MLSE equalizer offers superior performance and lower complexity over conventional equalizers. In the experimental verification, we experimentally demonstrate a C-band 56-Gb/s double-sideband 4-level pulse amplitude modulation (PAM-4) IM/DD transmission over 40-km standard single mode fiber exploiting the proposed refined MLSE without any optical amplifier, filter or dispersion managed modules at the receiver end, achieving a bit-error-ratio of 2.65×10−4, which is 2.28 orders of magnitude lower than the scheme using Volterra nonlinear equalizer.
Correction of overexposure in laser speckle contrast imaging
Authors: Földesy Péter , Siket Máté , Nagy Ádám , Jánoki Imre
Published: March 2022

Laser speckle contrast imaging (LSCI) is a method to visualize and quantify tissue
perfusion and blood flow. A common flaw in LSCI variants is their
sensitivity to the optical setup parameters and that they operate well
only on statistics of undistorted laser speckle patterns. The signal
saturation of the sensors makes the contrast calculation misleading;
hence the illumination level must be well controlled. We describe the
theoretical explanation for the saturation-caused degradation. We
introduce a linear extrapolation method to eliminate the overexposure
induced error up to an extent of 60-70% saturated pixel count. This,
depending on the contrast value and use case, enables to use 3-8 times
higher external illumination level with no deterioration of the
contrast calculation and thus the measured blood flow index. Our
method enables a higher signal-to-noise ratio in darker areas by
allowing the use of higher illumination, utilizing a larger portion of
the dynamic range of the sensors, and making the illumination level
setting less cumbersome.
Optical up-conversion-based cross-correlation for characterization of sub-nanosecond terahertz-wave pulses
Authors: Takida Yuma , Nawata Kouji , Notake Takashi , Otsuji Taiichi , Minamide Hiroaki
Published: March 2022

Using a nonlinear optical mixing known as a frequency up-conversion process, we demonstrate an optical cross-correlation technique for the detection and characterization of sub-nanosecond (sub-ns) terahertz (THz)-wave pulses. A monochromatic THz-wave pulse from an injection-seeded THz-wave parametric generator (is-TPG) was mixed with a near-infrared (NIR) pump pulse to generate a NIR idler pulse in a trapezoidal-prism-shaped MgO-doped lithium niobate crystal under the noncollinear phase-matching condition. By measuring pump-energy and crystal-length dependencies, we show that the frequency up-conversion of sub-ns THz-wave pulses with and without subsequent parametric amplification can be used for sensitive detection and intensity cross-correlation characterization, respectively. Using this cross-correlation technique, we reveal that the temporal profile of THz-wave pulses from the is-TPG driven by a 351-ps 1064-nm pump laser has slightly-frequency-dependent pulse width in the range of 150–190 ps at full width at half-maximum in the tunable range of 0.95–2.00 THz.
Manipulating the radial components of LG pump beam for ultrahigh-dimensional maximally entangled orbital angular momentum states
Authors: Xu Chuan , Xiao Lintao , He Jianlang , Zhang Han , Wei Dunzhao , Hu Xiaopeng , Xiao Min , Zhang Yong
Published: March 2022

High-dimensional maximally entangled orbital angular momentum (OAM) states are a promising resource for enhancing information capacity and robustness in quantum communication. However, it still lacks an effective method to increase the state dimensionality. Here, we theoretically propose an efficient scheme to generate maximally entangled OAM states of ultrahigh dimensionality by manipulating the radial components of a Laguerre-Gaussian (LG) pump beam. By optimizing the complex amplitudes of multiple radial modes of the LG pump light, one can feasibly achieve 101-dimensional OAM-based maximally entangled states. Our scheme has potential applications in high capacity quantum communication networks.
Mid-infrared biomimetic moth-eye-shaped polarization-maintaining and angle-insensitive metalens
Authors: Zhou Kongsi , Wang Bingxia , Tang Shiwei , Gao Yixiao , Liu Shan , Sheng Yan , Chen Jinjin , Dai Shixun , Shen Xiang
Published: March 2022

Metalenses can potentially reduce the size and complexity of existing cameras, displays, and other optical devices, owing to their capability of flexible manipulation of the polarization, amplitude, and phase of light. However, metalenses capable of maintaining polarization and broadband wavefront shaping under arbitrarily polarized excitation have not been studied. In this study, we present the first demonstration of a biomimetic moth-eye-shaped metalens for polarization-maintaining, broadband and angle-insensitive focusing under an arbitrarily polarized excitation in the mid-infrared waveband (3.1–8.0 µm). Modulation and focusing efficiencies of 92% and 90%, respectively, were achieved. Moreover, a bifocal moth-eye-shaped metalens operating at normal and oblique incidences was realized. Compared to previously reported metalenses, the one proposed in this study exhibited a better focusing under oblique incidence, ensuring light transmission as effectively as a traditional lens. This study paves the way for the development of polarization-maintaining, broadband, and angle-insensitive microscale optical devices and imaging systems.
All-dielectric multi-resonant bullseye antennas
Authors: Butcher Amy , High Alexander A.
Published: March 2022

Integrated devices that generate multiple optical resonances in the same volume can enhance on-chip nonlinear frequency generation, nonlinear spectroscopy, and quantum sensing. Here, we demonstrate circular Bragg antennas that exhibit multiple spatially overlapping, polarization-selective optical resonances. Using templated atomic layer deposition of TiO2, these devices can be fabricated on arbitrary substrates, making them compatible with a wide range of nonlinear materials and sensing targets, and couple efficiently to underlying films. In this work, we detail the design, simulation, and fabrication of all-dielectric multi-resonant bullseye antennas and characterize their performance using polarized broadband reflection spectroscopy.
X-Band photonic microwaves with phase noise below −180 dBc/Hz using a free-running monolithic comb
Authors: Kalubovilage Manoj , Endo Mamoru , Schibli Thomas R.
Published: March 2022

Free-running mode-locked monolithic optical frequency combs offer a compact and simple alternative to complicated optical frequency division schemes. Ultra-low free-running noise performance of these oscillators removes the necessity of external phase stabilization, making the microwave systems uncomplicated and compact with lower power consumption while liberating the sidebands of the carrier from servo bumps typically present around hundreds of kilohertz offsets. Here we present a free-running monolithic laser-based 8 GHz photonic microwaves generation and characterization with a cryogenically cooled power splitter to demonstrate a state-of-the-art phase noise floor of less than −180 dBc/Hz below 1 MHz offset from the carrier.
Thulium-doped fluorotellurite glass fibers for broadband S-band amplifiers
Authors: Wang Junjie , Jia Zhixu , Zhang Chuanze , Sun Yan , Ohishi Yasutake , Qin Weiping , Qin Guanshi
Published: March 2022

We demonstrated broadband S-band (1460–1530 nm) amplification in Tm3+-doped fluorotellurite glass fibers (TDFTFs) by using a 1400/1570 nm dual-wavelength pump technique. TDFTFs based on TeO2-BaF2-Y2O3 (TBY) glass were fabricated by using a rod-in-tube method. For an input signal power of 0 dBm (or 1 mW), a broadband positive net gain ranging from <1440 nm to 1546 nm was achieved in a 1.55-m-long TDFTF with a Tm3+ doping concentration of ∼4000 ppm, as the pump powers of the 1400 nm and 1570 nm lasers were 1.7 W and 0.14 W, respectively. The corresponding bandwidth for a net gain of >20 dB was ∼66 nm (1458–1524 nm), and the measured saturated output power was ∼24.84 dBm at 1490 nm. In addition, numerical simulation was performed by using the parameters of the TDFTFs and the pump lasers, and the noise figure was calculated to be <5.6 dB in the S band. Our results showed that the TDFTFs were promising gain media for constructing efficient broadband S-band fiber amplifiers.
BER improvement in SPAD-based photon-counting optical communication system by using automatic attenuation control technique
Authors: Wang Chen , Wang Jingyuan , Xu Zhiyong , Li Jianhua , Zhao Jiyong , Qi Ailin , Su Yang
Published: March 2022

In order to overcome the saturation of a single-photon avalanche diode (SPAD)-based receiver and keep the output counts at optimum level automatically, a new, to the best of our knowledge, scheme using the automatic attenuation control (AAC) technique is proposed. In the scheme, an AAC module is applied to attenuate excess incident photons. Furthermore, on the foundation of the bit error rate (BER) model of a photon-counting optical communication system, a reliable and efficient AAC algorithm is developed to compute the optimal attenuation factor. Based on the AAC algorithm, the optimal attenuation factors under different operation conditions are investigated. The results indicate that the incident optical intensity and signal-to-background ratio play an important role in determining the optimal attenuation factor. Moreover, at high incident optical intensity, the system BER utilized AAC module can be improved by 0.5 to 3 orders of magnitude. The AAC technique can effectively expand the dynamic range of the SPAD-based receiver.
Line-wise scanning-based super-resolution imaging
Authors: Tian Xin , Xiao Ying , Liu Rui , He Fang , Ma Jiayi
Published: March 2022

In this Letter, we present a novel, to the best of our knowledge, line-wise scanning-based super-resolution (LSSR) imaging method. To reduce point spread functions overlapping among pixels, we specifically present a super-resolution (SR) imaging architecture to capture a series of low-resolution images using a line-based optical multiplexing technique, which is able to achieve a good balance between imaging quality and speed. In addition, we propose an efficient joint reconstruction algorithm based on total variation and low-rank constraints to generate a high-resolution image from these low-resolution images that contain different spatial details. Meanwhile, existing stripe noises are efficiently suppressed. Experiments on real data show that LSSR imaging has significant advantages over other state-of-the-art methods in terms of visual quality and quantitative measurement.
Nano-scale ferroelectric domain differentiation in periodically poled lithium niobate with auger electron spectroscopy
Authors: McLoughlin Torrey , Randall Babbitt Wm. , Nakagawa Wataru
Published: March 2022

A new method for characterizing lithium niobate +/-Z ferroelectric polarization domains using Auger electron spectroscopy (AES) is presented. The domains of periodically poled samples are found to be differentiable using the peak amplitude of the Auger oxygen KLL transition, with -Z domains having a larger peak-amplitude as compared to +Z domains. The peak amplitude separation between domains is found to be dependent on the primary beam current, necessitating a balance between the insulating samples charging under the primary beam and achieving sufficient signal to noise in amplitude separation. AES amplitude-based domain characterization is demonstrated for fields of view (FOV) ranging from 1

μ

m to 78

μ

m. Domain spatial resolution of 91 nm is demonstrated at 1

μ

m FOV.
Akzeptierte Geschäftsprozesse gestalten und implementieren
Authors: Drewes Lars , Nissen Volker
Published: March 2022

Gemäß der Prozessakzeptanztheorie hat die Akzeptanz von Prozessen einen Einfluss auf deren korrekte Ausführung. Sollen Abweichungen und Manipulationen in der Prozessausführung, die auch ethisch negativ konnotiert sein können, verhindert werden, ist es notwendig zu verstehen, welche Faktoren einen Einfluss auf die Akzeptanz aufweisen. In der vorliegenden Arbeit wird der Einfluss von Selbstheilungsfähigkeiten im Prozess sowie der Einfluss eines damit verbundenen Verlustes der Kontrolle der Beteiligten über die Daten in zwei Experimenten untersucht. Dadurch, dass ein Algorithmus die Kontrolle über den Prozess übernimmt, ist hier die digitale Ethik betroffen. Die Basis für das Experiment bildet ein generischer Einkaufsprozess, der online über Amazon’s Mechanical Turk bereitgestellt wird. Die Prozessakzeptanz wird mit Hilfe eines Fragebogens aufgeteilt in die drei Dimensionen der Einstellung (kognitiv, affektiv, konativ) gemessen. Das erste Experiment zeigt, dass es einen signifikanten Unterschied in der Akzeptanz von Prozesse mit und ohne Selbstheilungsmechanismen gibt. Die Ergebnisse der Tests deuten darauf hin, dass die Selbstheilung nicht automatisch besser akzeptiert wird als wiederholte manuelle Anstrengungen. Dieses Ergebnis ist auch praktisch sehr wichtig, denn automatisierte Rekonstruktionen nehmen heute eine wichtige Rolle in der IT-gestützten Ausführung von Geschäftsprozessen ein. Eine vorläufige Erklärung ist, dass ein Verlust der Kontrolle der Teilnehmer über die Daten zu diesem scheinbar kontra-intuitiven Ergebnis führt. Im zweiten Experiment wird daher der Kontrollverlust untersucht. Es konnte dahingehend keine Signifikanz festgestellt werden, allerdings deutet die gemessene Teststärke darauf hin, dass das gewählte Testdesign möglicherweise nicht sensibel genug war, solche Unterschiede messen zu können. Weitere Untersuchungen sind daher nötig.
Host species is linked to pathogen genotype for the amphibian chytrid fungus (Batrachochytrium dendrobatidis)
Authors: Byrne Allison Q. , Waddle Anthony W. , Saenz Veronica , Ohmer Michel , Jaeger Jef R. , Richards-Zawacki Corinne L. , Voyles Jamie , Rosenblum Erica Bree
Published: March 2022

Host-pathogen specificity can arise from certain selective environments mediated by both the host and pathogen. Therefore, understanding the degree to which host species identity is correlated with pathogen genotype can help reveal historical host-pathogen dynamics. One animal disease of particular concern is chytridiomycosis, typically caused by the global panzootic lineage of the amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), termed Bd-GPL. This pathogen lineage has caused devastating declines in amphibian communities around the world. However, the site of origin for the common ancestor of modern Bd-GPL and the fine-scale transmission dynamics of this lineage have remained a mystery. This is especially the case in North America where Bd-GPL is widespread, but disease outbreaks occur sporadically. Herein, we use Bd genetic data collected throughout the United States from amphibian skin swabs and cultured isolate samples to investigate Bd genetic patterns. We highlight two case studies in Pennsylvania and Nevada where Bd-GPL genotypes are strongly correlated with host species identity. Specifically, in some localities bullfrogs (Rana catesbeiana) are infected with Bd-GPL lineages that are distinct from those infecting other sympatric amphibian species. Overall, we reveal a previously unknown association of Bd genotype with host species and identify the eastern United States as a Bd diversity hotspot and potential site of origin for Bd-GPL.
How do women prepare for pregnancy in a low-income setting? Prevalence and associated factors
Authors: Mwase-Musicha Loveness , Chipeta Michael G. , Stephenson Judith , Hall Jennifer A.
Published: March 2022

Background

Despite growing evidence of pregnancy preparation benefits, there is little knowledge on how women in developing countries prepare for pregnancy and factors influencing their preparedness for pregnancy. Here, we determine how women in Malawi prepare for pregnancy and factors associated with pregnancy preparation.

Methods

We used data from a previous cohort study comprising 4,244 pregnant mothers, recruited between March and December 2013 in Mchinji district, Malawi. Associations of pregnancy preparation with socio-demographic and obstetric factors were tested for using mixed effects ordinal regression, with the likelihood ratio and Wald’s tests used for variable selection and independently testing the associations.

Results

Most mothers (63.9%) did not take any action to prepare for their pregnancies. For those who did (36.1%), eating more healthily (71.9%) and saving money (42.8%) were the most common forms of preparation. Mothers who were married (adjusted odds-ratio (AOR 7.77 (95% CI [5.31, 11.25]) or with no or fewer living children were more likely to prepare for pregnancy (AOR 4.71, 95% CI [2.89,7.61]. Mothers with a period of two to three years (AOR 2.51, 95% CI [1.47, 4.22]) or at least three years (AOR 3.67, 95%CI [2.18, 6.23]) between pregnancies were more likely to prepare for pregnancy than women with first pregnancy or shorter intervals. On the other hand, teenage and older (≥ 35 years old) mothers were less likely to prepare for pregnancy (AOR 0.61, 95%CI [0.47, 0.80]) and AOR 0.49 95%CI [0.33, 0.73], respectively).

Conclusion

While preconception care may not be formally available in Malawi, our study has revealed that over a third of mothers took some action to prepare for pregnancy before conception. Although this leaves around two thirds of women who did not make any form of pregnancy preparation, our findings form a basis for future research and development of a preconception care package that suits the Malawian context.
AI-driven quantification of ground glass opacities in lungs of COVID-19 patients using 3D computed tomography imaging
Authors: Saha Monjoy , Amin Sagar B. , Sharma Ashish , Kumar T. K. Satish , Kalia Rajiv K.
Published: March 2022

Objectives

Ground-glass opacity (GGO)—a hazy, gray appearing density on computed tomography (CT) of lungs—is one of the hallmark features of SARS-CoV-2 in COVID-19 patients. This AI-driven study is focused on segmentation, morphology, and distribution patterns of GGOs.

Method

We use an AI-driven unsupervised machine learning approach called PointNet++ to detect and quantify GGOs in CT scans of COVID-19 patients and to assess the severity of the disease. We have conducted our study on the “MosMedData”, which contains CT lung scans of 1110 patients with or without COVID-19 infections. We quantify the morphologies of GGOs using Minkowski tensors and compute the abnormality score of individual regions of segmented lung and GGOs.

Results

PointNet++ detects GGOs with the highest evaluation accuracy (98%), average class accuracy (95%), and intersection over union (92%) using only a fraction of 3D data. On average, the shapes of GGOs in the COVID-19 datasets deviate from sphericity by 15% and anisotropies in GGOs are dominated by dipole and hexapole components. These anisotropies may help to quantitatively delineate GGOs of COVID-19 from other lung diseases.

Conclusion

The PointNet++ and the Minkowski tensor based morphological approach together with abnormality analysis will provide radiologists and clinicians with a valuable set of tools when interpreting CT lung scans of COVID-19 patients. Implementation would be particularly useful in countries severely devastated by COVID-19 such as India, where the number of cases has outstripped available resources creating delays or even breakdowns in patient care. This AI-driven approach synthesizes both the unique GGO distribution pattern and severity of the disease to allow for more efficient diagnosis, triaging and conservation of limited resources.