bluuebunny/crossref_metadata_2025 huggingface dataset:
Shutdown of multidrug transporterbmrCDmRNA expression mediated by the ribosome-associated endoribonuclease (Rae1) cleavage in a new cryptic ORF
Authors: Deves Valentin , Trinquier Aude , Gilet Laetitia , Alharake Jawad , Condon Ciarán , Braun Frédérique
Published: May 2023

Rae1 is a well-conserved endoribonuclease among Gram-positive bacteria, cyanobacteria, and the chloroplasts of higher plants. We have previously shown that Rae1 cleaves theBacillus subtilis yrzIoperon mRNA in a translation-dependent manner within a short open reading frame (ORF) calledS1025, encoding a 17-amino acid (aa) peptide of unknown function. Here, we map a new Rae1 cleavage site in thebmrBCDoperon mRNA encoding a multidrug transporter, within an unannotated 26-aa cryptic ORF that we have namedbmrX. Expression of thebmrCDportion of the mRNA is ensured by an antibiotic-dependent ribosome attenuation mechanism within the upstream ORFbmrB. Cleavage by Rae1 withinbmrXsuppressesbmrCDexpression that escapes attenuation control in the absence of antibiotics. Similar toS1025, Rae1 cleavage withinbmrXis both translation- and reading frame-dependent. Consistent with this, we show that translation-dependent cleavage by Rae1 promotes ribosome rescue by the tmRNA.
Transition from transperitoneal to retroperitoneal approach in laparoscopic living donor nephrectomy: team-based and individual learning curve: a cross-sectional study
Authors: Wahyudi Irfan , Adriansyah Ilham Azka , Yonathan Kevin , Widia Fina , Hamid Agus Rizal A , Mochtar Chaidir Arif
Published: May 2023

Background: Laparoscopic living donor nephrectomy (LLDN) is a standard practice for kidney donor transplantation due to fewer complications associated with the treatment. Retroperitoneal approach to LLDN is thought to be more advantageous in preventing injuries to various abdominal organs. However, the transition process from transperitoneal to retroperitoneal LLDN is important to ensure the best outcome for the patients. The aim of this study was to investigate the learning curve for retroperitoneal approach in LLDN among urologists in an individual and team-based approach

Methods: A retrospective analysis of retroperitoneal LLDN was performed on procedures performed by a kidney donor team consisting of four urologists from January 2019 to January 2022 at Cipto Mangunkusumo National General Hospital, Indonesia. The data were taken from pre-existing medical records. The learning curve for the operation time, warm ischemic time, and estimated blood loss was analyzed using cumulative sum (CUSUM) analysis. Phase 1 represents the initial learning curve, the phase 2 plateau represents the period of proficiency, while phase 3 represents the mastery period.

Results: A total of 127 retroperitoneal LLDN procedures were done during the study period by four operators with various experience. The average procedure needed to achieve proficiency was 16.5 procedures. Meanwhile, the average procedure needed to achieve mastery was 28 procedures. Shorter learning curve was achieved by operators with more experience in other laparoscopic procedures.

Conclusions: The learning curve for transition from transperitoneal to retroperitoneal approach to LLDN is relatively short and feasible for both individuals and teams of urologists. Therefore, transition to retroperitoneal approach is a feasible option to reduce the complication rate of LLDN.
Advancing posaconazole quantification analysis with a new reverse-phase HPLC method in its bulk and marketed dosage form
Authors: Rama Annamalai , Govindan Induja , Hebbar Srinivas , Chaturvedi Abhishek , Rani Usha , Naha Anup
Published: May 2023

Introduction: Posaconazole is a widely used antifungal drug, and its accurate quantification is essential for quality control and assessment of its pharmaceutical products. This study aimed to develop and validate a reverse-phase high-performance liquid chromatography (HPLC) analytical method for quantifying Posaconazole in bulk and dosage form.

Methods: The HPLC method was developed and validated based on International Conference on Harmonisation (ICH) guidelines. The developed method was then applied to quantify Posaconazole in a marketed tablet formulation. The method's specificity, linearity, precision, accuracy, robustness, and stability were evaluated.

Results: The developed HPLC method showed good linearity over a 2-20 μg/mL concentration range. The percentage recovery of Posaconazole from the bulk and marketed formulations was found to be 99.01% and 99.05%, respectively. The intra-day and inter-day precisions were less than 1%, and the method was stable under different conditions. The HPLC method was successfully applied to quantify Posaconazole in the marketed formulation.

Conclusion: The developed and validated HPLC method is reliable and efficient for analyzing Posaconazole in bulk and dosage forms. The method's accuracy, precision, specificity, linearity, robustness, and stability demonstrate its effectiveness. The method can be used for the quality control and assessment of Posaconazole-containing pharmaceutical products.
Visual diagnosis of female genital schistosomiasis in Zambian women from hand-held colposcopy: agreement of expert image review and association with clinical symptoms
Authors: Sturt Amy , Bristowe Henrietta , Webb Emily , Hansingo Isaiah , Phiri Comfort , Mudenda Maina , Mapani Joyce , Mweene Tobias , Levecke Bruno , Cools Piet , van Dam Govert , Corstjens Paul , Ayles Helen , Hayes Richard , Francis Suzanna , van Lieshout Lisette , Vwalika Bellington , Kjetland Eyrun , Bustinduy Amaya
Published: May 2023

Background: Female genital schistosomiasis (FGS) can occur in S. haematobium infection and is caused by egg deposition in the genital tract. Confirming a diagnosis of FGS is challenging due to the lack of a diagnostic reference standard. A 2010 expert-led consensus meeting proposed visual inspection of the cervicovaginal mucosa as an adequate reference standard for FGS diagnosis. The agreement of expert human reviewers for visual-FGS has not been previously described.

Methods: In two Zambian communities, non-menstruating, non-pregnant, sexually-active women aged 18-31 years participating in the HPTN 071 (PopART) Population-Cohort were enrolled in a cross-sectional study. Self-collected genital swabs and a urine specimen were collected at a home visit; trained midwives performed cervicovaginal lavage (CVL) and hand-held colposcopy at a clinic visit. S. haematobium eggs and circulating anodic antigen (CAA) were detected from urine. Two senior physicians served as expert reviewers and independently diagnosed visual-FGS as the presence of sandy patches, rubbery papules or abnormal blood vessels in cervicovaginal images obtained by hand-held colposcopy. PCR-FGS was defined as Schistosoma DNA detected by real-time PCR in any genital specimen (CVL or genital swab). 

Results: Of 527 women with cervicovaginal colposcopic images, 468/527 (88.8%) were deemed interpretable by Reviewer 1 and 417/527 (79.1%) by Reviewer 2. Visual-FGS was detected in 35.3% (165/468) of participants by expert review of colposcopic images by Reviewer 1 and in 63.6% (265/417) by Reviewer 2. Cohen’s kappa statistic for agreement between the two reviewers was 0.16, corresponding to "slight" agreement. The reviewers made concordant diagnoses in 38.7% (204/527) participants (100 negative, 104 positive) and discordant diagnoses in 31.8% (168/527) participants.

Conclusions: The unexpectedly low level of correlation between expert reviewers highlights the imperfect nature of visual diagnosis for FGS based on cervicovaginal images. This finding is a call to action for improved point-of-care diagnostics for female genital schistosomiasis.
Crowdinvesting Is an Innovative Method of Financing Companies’ Projects
Authors: Tsarkov Igor
Published: May 2023

The paper analyzes the essence of the concept of "crowdinvesting", its fea-tures in Russia, the ratio between risk and profitability of such investments, also formulates theoretical questions for further research, prospects for the development of this area and analyzes the implemented crowdinvesting projects on Russian sites. The work consists of 3 sections: the development of crowdfunding in Russia; why crowdinvesting is needed; crowdinvesting platforms in Russia.
The concept of culture war and its potential for the analysis of political and worldview conflicts
Authors: Polulyah D.
Published: May 2023

The purpose of this article is to identify the potential of the cultural war concept for the analysis of political and worldview conflicts in American and other modern societies. Based on the methods of case study, literature and statistics analysis, the article provides the main provisions of the concept and analyzes key academic discussions about the features of the application of this theoretical perspective to American social and political life. The author identifies two approaches to the analysis of cultural wars – empirical and systemic (bipolar). The classification of the “hot buttons” of cultural wars in modern, primarily Western, societies is given. The thesis is put forward that although it is impossible to reduce all moral confrontations to the conflict of “orthodox” and “progressivists”, the bipolar approach often turns out to be useful for understanding the most significant culture wars. The author comes to the conclusion that the thesis about culture wars being waged in the United States not only withstands the criticism put forward by skeptics, but also becomes more and more relevant against the backdrop of the contradictory trends of the modern world. This conclusion is consistent with theoretical and empirical studies of political psychology and sociology, pointing to the deep nature of citizens' opinions on moral and identity issues. The concept of culture war as a theoretical perspective that points to the fundamental nature of differences of opinion on moral and ethical issues can also shed light on processes taking place in other countries, including Russia.
Shedding Light on the Dark: The Impact of Legal Enforcement on Darknet Transactions
Authors: Chan Jason , He Shu , Qiao Dandan , Whinston Andrew
Published: May 2023

Practice and Policy-Oriented Abstract

Law enforcement bodies have largely responded to the increase in darknet activities through site shutdowns, which involve significant investment of policing resources. Despite these efforts, new darknet sites continue to show up after the site takedowns. We offer a new look at this issue by assessing the viability of selectively targeting large drug vendors operating on darknet sites. We find that the arrest of a major drug vendor reduced subsequent transaction levels by 39% and the number of remaining vendors by 56% on Silk Road 2.0. This deterrent effect also spilled over to drug vendors located in countries beyond the prosecutorial jurisdiction of the arrested vendor. We further find that small darknet drug vendors were most deterred by the arrest and vendors selling dangerous drugs were relatively more deterred. Our study findings hold policy-relevant implications to government agencies and law enforcement. Whereas site shutdowns can disrupt these markets momentarily, the selective targeting of large-scale drug vendors should be given serious consideration and used to a broader extent. The design of future enforcement strategies should also account for the finding that darknet markets are made up of both small-scale drug dealers new to the drug trade and large-scale drug syndicates.
Introducing Prescriptive and Predictive Analytics to MBA Students with Microsoft Excel
Authors: Diamant Adam
Published: May 2023

Managers are increasingly being tasked with overseeing data-driven projects that incorporate prescriptive and predictive models. Furthermore, basic knowledge of the data analytics pipeline is a fundamental requirement in many modern organizations. Given the central importance of analytics in today’s business environment, there is a growing demand for educational pedagogies that give students the opportunity to learn the fundamentals while also familiarizing them with how such tools are applied. However, a tension exists between the introduction of real-world problems that students can analyze and extract insight from and the need for prerequisite knowledge of mathematical concepts and programming languages such as Python/R. As a consequence, this paper describes an application-focused course that uses Microsoft Excel and mathematical programming to introduce MBA students with nontechnical backgrounds to tools from both prescriptive and predictive analytics. While students’ gain proficiency in managing data and creating optimization and machine learning models, they are also exposed to broader business concepts. Teaching evaluations indicate that the course has helped students further develop their practical skills in Microsoft Excel, gain an appreciation of the real-world impact of data analytics, and has introduced them to a discipline they originally believed was best suited for more technically focused professionals.

Supplemental Material: Supplemental materials are available at https://doi.org/10.1287/ited.2023.0286 .
Pay Suppression in Social Impact Contexts: How Framing Work Around the Greater Good Inhibits Job Candidate Compensation Demands
Authors: Hussain Insiya , Pitesa Marko , Thau Stefan , Schaerer Michael
Published: May 2023

Past research suggests that when organizations communicate the benefits of their work for human welfare—that is, use a social impact framing for work—job candidates are willing to accept lower wages because they expect the work to be personally meaningful. We argue that this explanation overlooks a less socially desirable mechanism by which social impact framing leads to lower compensation demands: the perception among job candidates that requesting higher pay will breach organizational expectations to value work for its intrinsic (rather than extrinsic) rewards, or constitute a motivational norm violation. We find evidence for our theory across five studies: a qualitative study (Study 1), a hiring experiment with undergraduate students (Study 2), an online labor market field experiment (Study 3), a vignette-based simulation (Study 4), and a stimulus sampling study using multiple occupations (Study 5). Exploratory analyses find that the negative effects are unique to monetary (versus nonmonetary) job rewards. Together, results uncover a novel mechanism by which emphasizing work for the greater good leads job candidates to accept lower wages—one that reflects candidates self-censoring on pay from concerns about violating organizational norms rather than solely from a willingness to trade higher pay for potentially meaningful work. Our research contributes to understandings of how social responsibility messaging impacts workers’ perceptions of organizations and negotiation behavior. It also holds implications for emerging scholarship on managers’ implicit theories of employee work motivation.

Funding: I. Hussain thanks the Dean’s Research Excellence Grant at the McCombs School of Business at the University of Texas Austin for generous financial support. The research also benefitted from Tier 1 Academic Research Funds awarded to M. Pitesa [Grant C207/MSS19B011] and M. Schaerer [Grant C207/MSS22B011] by the Ministry of Education, Singapore, and the Research & Development Fund of INSEAD.

Supplemental Material: The online supplement is available at https://doi.org/10.1287/orsc.2023.1675 .
Assessment of the feasibility of intermittent self-catheterisation among patients with neurogenic bladder
Authors: Balhi Salma
Published: May 2023

Intermittent Self-Catheterisation (ISC) has been in practice for more than 40 years. It is considered the gold standard in the management of urinary retention among patients with neurogenic bladder. Most learned societies agree with the benefits of ISC. The ISC technique is simple but must be rigorous. Therefore, a therapeutic patient education in intermittent self-catheterisation (TPE-ISC) programme is fundamental to ensure the correct technique is taught and learned. Educational diagnosis should be the first step in the TPE-ISC programme and aims to assess the learning abilities and the needs of each patient. This paper proposed a diagnostic approach to screen potential barriers that may alter the learning abilities of patients undergoing ISC.
Stroke advanced clinical practitioner and stroke specialist nurse: what is the difference?
Authors: Standing Laura M , Hoare Amy , Irwin Kerry , Lawrence Stacey , Carr Peter , Sandler David , Sims Don , Appleton Jason P
Published: May 2023

The stroke advance clinical practitioner (ACP) and stroke specialist nurse (SSN) are two vitally important roles within the hyper acute stroke unit, acute stroke unit and spoke sites that provide acute stroke care for continued rehabilitation until the point of discharge. The SSN role has been developed over the past decade, whereas the ACP role is much newer. While there are similarities between the two roles, there are some core differences that allow the two roles to coexist and support one another. It is important to understand the two roles, the differences and how each will benefit from the other, as this will allow teams working within hyper acute stroke units and acute stroke units to work to their full potential, while ensuring professional and patient safety and enhancing job satisfaction and patient care.
Calculation of Swath Width and Swath Displacement for Uncrewed Aerial Spray Systems
Authors: Bonds Jane A.S. , Fritz Brad , Thistle Harold W.
Published: May 2023

Highlights

Recent research has focused on the use of Uncrewed Aerial Spray Systems (UASS) for their potential to fill the gap between crewed aircraft and ground application equipment.

The spray distribution in swath is highly variable to the point that using the typical metric of uniformity alone to define swath can no longer apply, we present a method that considers dose and uniformity.

The swath was rarely found to be directly beneath the flightline, the swath displacement and offsetting can be significant and larger than the assumed swath width.

This paper presents the development of an evidence-based, repeatable mathematical solution to the determination of swath width and swath displacement for UASS for calibration and targeting purposes.

Abstract. Recent research has focused on the use of Uncrewed Aerial Spray Systems (UASS) for their potential to fill the gap between crewed aircraft and ground application, with UASS being able to be used over less accessible areas than ground equipment, being more appropriate to treat smaller, dispersed targets, and typically available at reduced cost and complexity when compared to crewed aircraft. However, there is limited literature focusing on the proper setup and use of these systems. The objective of this study was to design and conduct a series of large-scale, conceptually linked studies to provide data that is used to guide system optimization and the development of predictive models. An uncrewed system coupled with three nozzle types covering three droplet size classifications was used to conduct swath characterization and drift trials designed to establish effective swath widths, deposition variability, swath displacement, and drift. System and nozzle type, along with nozzle position and wind direction, significantly impacted the spray deposition patterns within and downwind of the effective swath. The spray distribution in a swath is highly variable, to the point that using the typical metric of uniformity alone to define swath can no longer apply. In addition, the swath was rarely found to be directly beneath the flightline, and swath offsetting can be significant and larger than the assumed swath width. An iterative solution has been developed that uses a combination of effective dose and uniformity to define swath width. The offsetting of the swath due to interactions with ambient air has also been defined using the Center of Deposition. The aim is to be able to distinguish between in-swath deposition and drift. The approach to defining swath width and the displacement of the swath is presented. The goal is to develop a real-time onboard navigation system that can reset the flight line in response to wind-driven swath displacement. This allows increased deposition within the target zone and reduces off-target losses. Keywords: Aerial application, Offset, Swath displacement, Swath width, Unmanned aerial spray system.
A Taxonomic Classification of Insider Threats: Existing Techniques, Future Directions & Recommendations
Authors: Rauf Usman , Mohsen Fadi , Wei Zhiyuan
Published: May 2023

In the last two decades, the number of rapidly increasing cyber incidents (i.e., data theft and privacy breaches) shows that it is becoming enormously difficult for conventional defense mechanisms and architectures to neutralize modern cyber threats in a real-time situation. Disgruntled and rouge employees/agents and intrusive applications are two notorious classes of such modern threats, referred to as Insider Threats, which lead to data theft and privacy breaches. To counter such state-of-the-art threats, modern defense mechanisms require the incorporation of active threat analytics to proactively detect and mitigate any malicious intent at the employee or application level. Existing solutions to these problems intensively rely on co-relation, distance-based risk metrics, and human judgment. Especially when humans are kept in the loop for access-control policy-related decision-making against advanced persistent threats. As a consequence, the situation can escalate and lead to privacy/data breaches in case of insider threats. To confront such challenges, the security community has been striving to identify anomalous intent for advanced behavioral anomaly detection and auto-resiliency (the ability to deter an ongoing threat by policy tuning). Towards this dimension, we aim to review the literature in this domain and evaluate the effectiveness of existing approaches per our proposed criteria. According to our knowledge, this is one of the first endeavors toward developing evaluation-based standards to assess the effectiveness of relevant approaches in this domain while considering insider employees and intrusive applications simultaneously. There have been efforts in literature towards describing and understanding insider threats in general. However, none have addressed the detection and deterrence element in its entirety, hence making our contribution one of a kind. Towards the end of this article, we enlist and discuss the existing data sets. The data sets can help understand the attributes that play crucial roles in insider threat detection. In addition, they can be beneficial for testing the newly designed security solutions in this domain. We also present recommendations for establishing a baseline standard for analyzing insider-threat data sets. This baseline standard could be used in the future to design resilient architectures and provide a road map for organizations to enhance their defense capabilities against insider threats.
Dvojí přístup znalce k posouzení havárie stavby
Authors: Mikš Lubomír
Published: May 2023

Článek ukazuje, jak důležité je podrobné a přesné hodnocení všech dostupných dokumentů a zjištěných skutečností, aby znalec nedošel k chybnému závěru posudku. Současně zdůrazňuje úlohu vlastníka nemovitosti v procesu životnosti stavby a zamýšlí se nad kvalitou projektového záměru.
Central wavelength estimation in spectral imaging behind a diffuser via deep learning
Authors: Tsukada Takumi , Watanabe Wataru
Published: May 2023

Multispectral imaging through scattering media is an important practical issue in the
field of sensing. The light from a scattering medium is expected to
carry information about the spectral properties of the medium, as well
as geometrical information. Because spatial and spectral information
of the object is encoded in speckle images, the information about the
structure and spectrum of the object behind the scattering medium can
be estimated from those images. Here we propose a deep learning-based
strategy that can estimate the central wavelength from speckle images
captured with a monochrome camera. When objects behind scattering
media are illuminated with narrowband light having different spectra
with different spectral peaks, deep learning of speckle images
acquired at different central wavelengths can extend the spectral
region to reconstruct images and estimate the central wavelengths of
the illumination light. The proposed method achieves central
wavelength estimation in 1 nm steps for objects whose central
wavelength varies in a range of 100 nm. Because our method can
achieve image reconstruction and central wavelength estimation in a
single shot using a monochrome camera, this technique will pave the
way for multispectral imaging through scattering media.
Cavity-birefringence-based manipulation of long-duration optical pulses in a passively mode-locked fiber laser with large normal dispersion
Authors: Liu Jing , Zhao Junqing , Li Lei
Published: May 2023

Optical pulse manipulation in the large normal dispersion regime through intracavity birefringence management is demonstrated experimentally in an erbium-doped fiber (EDF) laser, for the first time to the best of our knowledge. The EDF laser is passively mode-locked based on a nonlinear amplifying loop mirror (NALM) in a figure-of-eight (f-8) configuration. Different lengths of the same type of polarization-maintaining fiber (PMF) are incorporated into the NALM to vary the net cavity birefringence. For each length of PMF, various polarization states and pump powers were tested and compared to achieve a pulse duration tuning range as large as possible. For comparison, these polarization states and pump powers were also studied by incorporating the PMF into the unidirectional loop of the f-8 cavity. Our results reveal some new features for the management of cavity birefringence that can enable long-duration pulse manipulation in the large normal dispersion regime.
Retinal blood flow speed quantification at the capillary level using temporal autocorrelation fitting OCTA [Invited]
Authors: Hwang Yunchan , Won Jungeun , Yaghy Antonio , Takahashi Hiroyuki , Girgis Jessica M. , Lam Kenneth , Chen Siyu , Moult Eric M. , Ploner Stefan B. , Maier Andreas , Waheed Nadia K. , Fujimoto James G.
Published: May 2023

Optical coherence tomography angiography (OCTA) can visualize vasculature structures, but provides limited information about blood flow speed. Here, we present a second generation variable interscan time analysis (VISTA) OCTA, which evaluates a quantitative surrogate marker for blood flow speed in vasculature. At the capillary level, spatially compiled OCTA and a simple temporal autocorrelation model, ρ(τ) = exp(-ατ), were used to evaluate a temporal autocorrelation decay constant, α, as the blood flow speed marker. A 600 kHz A-scan rate swept-source OCT prototype instrument provides short interscan time OCTA and fine A-scan spacing acquisition, while maintaining multi mm2 field of views for human retinal imaging. We demonstrate the cardiac pulsatility and assess repeatability of α measured with VISTA. We show different α for different retinal capillary plexuses in healthy eyes and present representative VISTA OCTA in eyes with diabetic retinopathy.
Geometrical optical analysis of a gradient refractive index microresonator
Authors: Chen Tianci , Kang Zhaofeng , Yang Yu , Zhao Shuai , Zhang Jun , Zhang Lei , Wang Keyi
Published: May 2023

Optical microresonators confine light to small volumes through resonant circulation. Herein, whispering gallery mode (WGM) microresonators have high Q factors among these microresonators, which have significant research value in the fields of fundamental physics research and optoelectronic devices. However, maintaining a very high surface finish on the side of the microresonator is necessary, as is keeping a coupling distance of tens of nanometers between the microresonator and the coupling waveguide. Thus, this makes the fabrication, coupling, and packaging of the microresonator very difficult and seriously hinders the practical application of the microresonator. In this study, the concept of gradient refractive index (GRIN) microresonator is proposed, and the radial GRIN is introduced to change the light direction and form a closed optical path within the microresonator. Herein, the mode field position of the GRIN microresonator is derived from the light transmission equation, and the theoretical result is proved by finite difference time domain (FDTD) simulation. Hence, there are several advantages to using this novel optical microresonator, including its high Q factor, strong coupling stability, and ease of integration.
Nanometer-precision surface metrology of millimeter-sized stepped objects using full-cascade-linked synthetic-wavelength digital holography using a line-by-line full-mode-extracted optical frequency comb
Authors: Hase Eiji , Tokizane Yu , Sadahiro Kazuki , Minamikawa Takeo , Morohashi Isao , Yasui Takeshi
Published: May 2023

Digital holography (DH) is a powerful tool for the surface profilometry of objects with sub-wavelength precision. In this article, we demonstrate full-cascade-linked synthetic-wavelength DH for nanometer-precision surface metrology of millimeter-sized stepped objects. 300 modes of optical frequency comb (OFC) with different wavelengths are sequentially extracted at a step of mode spacing from a 10GHz-spacing, 3.72THz-spanning electro-optic modulator OFC. The resulting 299 synthetic wavelengths and a single optical wavelength are used to generate a fine-step wide-range cascade link covering within a wavelength range of 1.54 µm to 29.7 mm. We determine the sub-millimeter and millimeter step differences with axial uncertainty of 6.1 nm within the maximum axial range of 14.85 mm.
Photonic compressive sampling of wideband sparse radio frequency signals with 1-bit quantization
Authors: Yang Bo , Xu Qing , Chi Hao , Liu Zining , Yang Shuna
Published: May 2023

Photonic compressive sampling (PCS) is an effective method to recover wideband sparse radio frequency (RF) signals. However, the noisy and high-loss photonic link leads to signal-to-noise ratio (SNR) degradation of the RF signal to be tested, which limits the recovery performance of the PCS system. In this paper, a random demodulator-based PCS system with 1-bit quantization is proposed. The system consists of a photonic mixer, a low-pass filter, a 1-bit analog-to-digital converter (ADC), and a digital signal processor (DSP). The 1-bit quantized result is used to recover the spectra of the wideband sparse RF signal with the binary iterative hard thresholding (BIHT) algorithm, which can alleviate the negative impact of the SNR degradation caused by the photonic link. A full theoretical framework of the PCS system with 1-bit quantization is given. Simulation results show that the PCS system with 1-bit quantization can provide better recovery performance than the traditional PCS system under low SNR and stringent bit budget.
Direct calibration of laser intensity via Ramsey interferometry for cold atom imaging
Authors: Altuntaş Emine , Spielman I. B.
Published: May 2023

A majority of ultracold atom experiments utilize resonant absorption imaging techniques to obtain the atomic density. To make well-controlled quantitative measurements, the optical intensity of the probe beam must be precisely calibrated in units of the atomic saturation intensity Isat. In quantum gas experiments, the atomic sample is enclosed in an ultra-high vacuum system that introduces loss and limits optical access; this precludes a direct determination of the intensity. Here, we use quantum coherence to create a robust technique for measuring the probe beam intensity in units of Isat via Ramsey interferometry. Our technique characterizes the ac Stark shift of the atomic levels due to an off-resonant probe beam. Furthermore, this technique gives access to the spatial variation of the probe intensity at the location of the atomic cloud. By directly measuring the probe intensity just before the imaging sensor our method in addition yields a direct calibration of imaging system losses as well as the quantum efficiency of the sensor.
High refractive index dielectric coating on plasmonic nanoantennas for strong visible light absorption in small transition metal nanoparticle reactors
Authors: Wang Qiuyan , Deng Liren , Zhou Guo , Zhu Yukun , Han Runqi , Huang Yu
Published: May 2023

A more practical model for plasmonic core@shell–satellite antenna–reactor photocatalysts is promoted. In contrast to the mainstream view, total light absorption in the Pt nanoparticle (NP) reactors can be further improved by 70% after coating a 10-nm-thick high refractive index TiO2 shell on the large Ag antenna as a result of more Pt NPs undergoing high absorption enhancement. The enhancement effect is maximized at the electric quadrupole (EQ) resonance. Considering the high refractive index of the TiO2 coating and the embedding of the Pt NPs, the underlying physics is addressed within classical electrodynamics, making a necessary supplement to the conventional plasmonic near-field enhancement mechanism. These findings provide a general strategy for developing novel, to the best of our knowledge, visible light photocatalysts made of transition metals directly.
Lasing behavior of a nematic liquid crystal microdroplet depending on the irradiation position
Authors: Uchida Yoshiaki , Kumazaki Mahiro , Naruta Takuya , Nishiyama Norikazu
Published: May 2023

This paper reports the random lasing and whispering gallery mode (WGM) lasing in dye-doped nematic liquid crystal (NLC) droplets. We discuss the emission behavior of the droplets in detail. Their lasing behavior depends on irradiation position and droplet diameter. Moreover, the two types of lasers likely share energy. Naturally, stopping one increases the efficiency of the other. Besides, the coexistence of the two types of lasers in an NLC droplet offers a controllable dye laser emitting two lights in different wavelength ranges.
Vernier effect based on hybrid fiber interferometers: a new tool for wavelength switchability and adjustable free spectral range fiber lasing
Authors: Al-Rubaiyee Hussein Alaa , Kadhim Al-Hayali Sarah , Al-Janabi Abdul Hadi
Published: May 2023

In optical communications systems, the used filter and/or demultiplexer needs to have a broad free spectral range (FSR) in order to accommodate more channels and have acceptable interchannel crosstalk. The Vernier effect applied to fiber filters is a recent effective tool to enlarge the FSR. Here, by harnessing the Vernier effect of a hybrid interferometer consisting of a Mach–Zehnder interferometer (MZI) and Sagnac interferometer (SI), we proposed and experimentally demonstrated a new kind of comb filter for a switchable and interval adjustable multi-wavelength C-band erbium-doped fiber laser (EDFL) application. In the designed comb filter, the MZI is composed of bi-tapered polarization-maintaining fibers (PMFs) fabricated by fusion splicing and has the function of achieving the switchability of the proposed dual-wavelength EDFL. The SI configured by nesting tapered PMF is employed as a switchable and wavelength-spacing tuning component of triple-wavelength EDFL. In this experiment, the FSR of the MZI and the SI is designed to be close but not equal, which could be achieved by properly adjusting the length of the employed PMF, so the Vernier effect can exist and a comb spectrum with an obvious envelope is obtained. Through the adjustment of the polarization controller (PC1) and (PC2) inside the cavity, a switchable and interval-adjustable multi-wavelength EDFL was achieved. To the best of the authors’ knowledge, this is the first time that an all-fiber hybrid filter based on the Vernier effect has been used to manipulate the spectral output characteristic of an EDFL and achieve a switchable multi-wavelength fiber laser.
Randomized whispering-gallery-mode microdisk laser arrays via cavity deformations for anti-counterfeiting labels
Authors: Mao Wangqi , Gao Xinyu , Li Bo , Zhang Yaqiang , Wang Pei , Dong Hongxing , Zhang Long
Published: May 2023

Optical physical unclonable functions (PUFs) have emerged as a promising strategy for effective and unbreakable anti-counterfeiting. However, the unpredictable spatial distribution and broadband spectra of most optical PUFs complicate efficient and accurate verification in practical anti-counterfeiting applications. Here, we propose an optical PUF-based anti-counterfeiting label from perovskite microlaser arrays, where randomness is introduced through vapor-induced microcavity deformation. The initial perovskite microdisk laser arrays with regular positions and uniform sizes are fabricated by femtosecond laser direct ablation. By introducing vapor fumigation to induce random deformations in each microlaser cavity, a laser array with completely uneven excitation thresholds and narrow-linewidth lasing signals is obtained. As a proof of concept, we demonstrated that the post-treated laser array can provide fixed-point and random lasing signals to facilitate information encoding. Furthermore, different emission states of the lasing signal can be achieved by altering the pump energy density to reflect higher capacity information. A threefold PUF (excited under three pump power densities) with a resolution of 5×5 pixels exhibits a high encoding capacity (1.43×1045), making it a promising candidate to achieve efficient authentication and high security with anti-counterfeiting labels.
AlGaN solar-blind phototransistor capable of directly detecting sub-fW signals: self-depletion and photorecovery of full-channel 2DEG enabled by a quasi-pseudomorphic structure
Authors: Lu Jiabing , Lv Zesheng , Jiang Hao
Published: May 2023

Heterojunction field-effect phototransistors using two-dimensional electron gas (2DEG) for carrier transport have great potential in photodetection owing to its large internal gain. A vital factor in this device architecture is the depletion and recovery of the 2DEG under darkness and illumination. This is usually achieved by adding an external gate, which not only increases the complexity of the fabrication and the electrical connection but also has difficulty ensuring low dark current (I
dark
). Herein, a quasi-pseudomorphic AlGaN heterostructure is proposed to realize the self-depletion and photorecovery of the 2DEG, in which both the barrier and the channel layers are compressively strained, making the piezoelectric and spontaneous polarization reverse, thus depleting the 2DEG and tilting the entire barrier and channel band to form two built-in photogates. The fabricated solar-blind phototransistors exhibit a very low I
dark
below 7.1×10−10  mA/mm, a superhigh responsivity (R) of 2.9×109  A/W, a record high detectivity (D*) of 4.5×1021 Jones, and an ultrafast response speed at the nanosecond level. The high performance is attributed to the efficient depletion and recovery of the full 2DEG channel by the two photogates, enabling direct detection of the sub-fW signal. This work provides a simple, effective, and easily integrated architecture for carrier control and supersensitive photodetection based on polarization semiconductors.
High concentrations of floating neustonic life in the plastic-rich North Pacific Garbage Patch
Authors: Chong Fiona , Spencer Matthew , Maximenko Nikolai , Hafner Jan , McWhirter Andrew C. , Helm Rebecca R.
Published: May 2023

Floating life (obligate neuston) is a core component of the ocean surface food web. However, only 1 region of high neustonic abundance is known so far, the Sargasso Sea in the Subtropical North Atlantic gyre, where floating life provides critical habitat structure and ecosystem services. Here, we hypothesize that floating life is also concentrated in other gyres with converging surface currents. To test this hypothesis, we collected samples through the eastern North Pacific Subtropical Gyre in the area of the North Pacific “Garbage Patch” (NPGP) known to accumulate floating anthropogenic debris. We found that densities of floating life were higher inside the central NPGP than on its periphery and that there was a positive relationship between neuston abundance and plastic abundance for 3 out of 5 neuston taxa, Velella, Porpita, and Janthina. This work has implications for the ecology of subtropical oceanic gyre ecosystems.
Characterization of a pathway of genomic instability induced by R-loops and its regulation by topoisomerases in E. coli
Authors: Brochu Julien , Vlachos-Breton Émilie , Irsenco Dina , Drolet Marc
Published: May 2023

The prototype enzymes of the ubiquitous type IA topoisomerases (topos) family areEscherichia colitopo I (topA) and topo III (topB). Topo I shows preference for relaxation of negative supercoiling and topo III for decatenation. However, as they could act as backups for each other or even share functions, strains lacking both enzymes must be used to reveal the roles of type IA enzymes in genome maintenance. Recently, marker frequency analysis (MFA) of genomic DNA fromtopA topBnull mutants revealed a major RNase HI-sensitive DNA peak bordered byTer/Tus barriers, sites of replication fork fusion and termination in the chromosome terminus region (Ter). Here, flow cytometry for R-loop-dependent replication (RLDR), MFA, R-loop detection with S9.6 antibodies, and microscopy were used to further characterize the mechanism and consequences of over-replication in Ter. It is shown that the Ter peak is not due to the presence of a strong origin for RLDR in Ter region; instead RLDR, which is partly inhibited by the backtracking-resistantrpoB*35mutation, appears to contribute indirectly to Ter over-replication. The data suggest that RLDR from multiple sites on the chromosome increases the number of replication forks trapped atTer/Tus barriers which leads to RecA-dependent DNA amplification inTerand to a chromosome segregation defect. Overproducing topo IV, the main cellular decatenase, does not inhibit RLDR or Ter over-replication but corrects the chromosome segregation defect. Furthermore, our data suggest that the inhibition of RLDR by topo I does not require its C-terminal-mediated interaction with RNA polymerase. Overall, our data reveal a pathway of genomic instability triggered by R-loops and its regulation by various topos activities at different steps.
Spatiotemporal distribution of schistosomiasis transmission risk in Jiangling County, Hubei Province, P.R. China
Authors: Feng Jiaxin , Zhang Xia , Hu Hehua , Gong Yanfeng , Luo Zhuowei , Xue Jingbo , Cao Chunli , Xu Jing , Li Shizhu
Published: May 2023

Objective

This study aims to explore the spatiotemporal distribution of schistosomiasis in Jiangling County, and provide insights into the precise schistosomiasis control.

Methods

The descriptive epidemiological method and Joinpoint regression model were used to analyze the changes in infection rates of humans, livestock, snails, average density of living snails and occurrence rate of frames with snails in Jiangling County from 2005 to 2021. Spatial epidemiology methods were used to detect the spatiotemporal clustering of schistosomiasis transmission risk in Jiangling county.

Results

The infection rates in humans, livestock, snails, average density of living snails and occurrence rate of frames with snails in Jiangling County decreased from 2005 to 2021 with statistically significant. The average density of living snails in Jiangling County was spatially clustered in each year, and the Moran’s I varied from 0.10 to 0.26. The hot spots were mainly concentrated in some villages of Xionghe Town, Baimasi Town and Shagang Town. The mean center of the distribution of average density of living snails in Jiangling County first moved from northwest to southeast, and then returned from southeast to northwest after 2014. SDE azimuth fluctuated in the range of 111.68°-124.42°. Kernal density analysis showed that the high and medium-high risk areas of Jiangling County from 2005 to 2021 were mainly concentrated in the central and eastern of Jiangling County, and the medium-low and low risk areas were mainly distributed in the periphery of Jiangling County.

Conclusions

The epidemic situation of schistosomiasis decreased significantly in Jiangling County from 2005 to 2021, but the schistosomiasis transmission risk still had spatial clustering in some areas. After transmission interruption, targeted transmission risk intervention strategies can be adopted according to different types of schistosomiasis risk areas.
Association between recent COVID-19 diagnosis, depression and anxiety symptoms among slum residents in Kampala, Uganda
Authors: Wafula Solomon T. , Ninsiima Lesley L. , Mendoza Hilbert , Ssempebwa John C. , Walter Florian , Musoke David
Published: May 2023

Background

Despite the known link between poor living conditions and mental health, there has been little research on the mental health of slum dwellers worldwide. Although the Coronavirus disease 2019 (COVID-19) pandemic has led to an increase in mental health issues, little focus has been given to the impact on slum dwellers. The study aimed to investigate the association between recent COVID-19 diagnosis and the risk of depression and anxiety symptoms among people living in an urban slum in Uganda.

Methods

A cross-sectional study was conducted among 284 adults (at least 18 years of age) in a slum settlement in Kampala, Uganda between April and May 2022. We assessed depression symptoms and anxiety using validated Patient Health Questionnaire (PHQ-9) and Generalized Anxiety Disorder assessment tool (GAD-7) questionnaires respectively. We collected data on sociodemographic characteristics, and self-reported recent COVID-19 diagnosis (in the previous 30 days). Using a modified Poisson regression, adjusted for age, sex, gender and household income, we separately provided prevalence ratios and 95% confidence intervals for the associations between recent COVID-19 diagnosis and depressive and anxiety symptoms.

Results

Overall, 33.8% and 13.4% of the participants met the depression and generalized anxiety screening criteria respectively and 11.3% were reportedly diagnosed with COVID-19 in the previous 30 days. People with recent COVID-19 diagnosis were more likely to be depressed (53.1%) than those with no recent diagnosis (31.4%) (p<0.001). Participants who were recently diagnosed with COVID-19 reported higher prevalence of anxiety (34.4%) compared to those with no recent diagnosis of COVID-19 (10.7%) (p = 0.014). After adjusting for confounding, recent diagnosis with COVID-19 was associated with depression (PR = 1.60, 95% CI 1.09–2.34) and anxiety (PR = 2.83, 95% CI 1.50–5.31).

Conclusion

This study suggests an increased risk of depressive symptoms and GAD in adults following a COVID-19 diagnosis. We recommend additional mental health support for recently diagnosed persons. The long-term of COVID-19 on mental health effects also need to be investigated.