bluuebunny/crossref_metadata_2025 huggingface dataset:
In silico prediction of HBD gene variants in the Iranian population
Authors: Moradi Keivan , Mohammadi Aboozar , Kazeminia Mohsen
Published: March 2021

Background

The quantification of hemoglobin A2 (Hb A2; α2δ2) is used as a valuable test to differentiate α- and ß-thal carriers in clinical laboratories. Therefore, the HBD (δ-globin) gene variants could result in reduced levels of Hb A2 and have implications for thalassemia screening programs. The aim of the present study was to predict the consequences of HBD gene variants identified in the Iranome project.

Results

The highest number of variants was in the Persian Gulf Islanders. The variants of p.Gln132Glu (HBD: c.394C>G), p.Gly17Arg (HBD: c.49G>C), p.Thr5Ile (HBD: c.14C>T), and p.Ala28Ser (HBD: c.82G>T) presented damage results in three or more prediction tools. In addition, it seems that the p.Gly30= (HBD: c.90C>T) decreases the use of authentic splice and, instead, creates a new donor splice site (DSS) or leads to the use of a cryptic DSS.

Conclusions

Most of these variants have been associated with a decrease in Hb A2 levels. Due to the high mutational diversity in the HBB gene in the Iranian population and the use of Hb A2 quantification to differentiate α- and ß-thal carriers among Iranian clinical laboratories, some attention should be taken to a possible co-inheritance of HBD gene variants to avoid the misdiagnosis of ß-thal carriers.
The relationship between knee-ankle muscle strength and performance tests in young female adults with flexible pes planus
Authors: Bakırhan Serkan , Elibol Nuray , Özkeskin Mehmet , Özden Fatih
Published: March 2021

Background

A decrease in muscular activation of the knee and ankle is one of the primary reasons for pes planus. The muscle strength of the knee and ankle in patients with pes planus may affect the performance tests which consists of daily life activities. The aim of the study was to determine the relationship between knee and ankle muscle strength with performance tests in young female adults with flexible pes planus. In addition, we also aimed to observe whether the severity of pes planus affects the ankle muscle strength and performance test scores. We carried out a cross-sectional single-center study. The muscle strength measurement of knee flexion-extension, ankle dorsal-plantar flexion, and ankle inversion-eversion movements were evaluated with the manual muscle test (MMT) device. The timed up and go test (TUG), 5-repeat sit-and-stand test (5STS), and 10-m walk test (10MWT) were used to evaluate knee and ankle performance.

Results

A significant difference was found only for the five-repetitive sit-and-stand test among the classified groups considering the pes planus grade (p < 0.05). There was no significant difference between groups for other parameters (p > 0.05). In correlation analysis, there was only a relationship between the timed up and go test (TUG) with left foot dorsal flexor muscle strength and between 10-m walk test (10MWT) with right foot invertor muscle strength (r1 = − 0.288, r2 = − 0.288, p < 0.05).

Conclusions

The results of this study reveal that the duration of 5STS was significantly lower in the second degree pes planus group. TUG test score showed low negative correlation with left foot dorsal flexor muscle strength. In addition, the scores of 10MWT exhibited poor negative correlation with right foot invertor muscle strength. Regarding other parameters, no significant correlations were found.
COVID-induced pancreatitis: case report
Authors: Wifi Mohamed-Naguib , Nabil Ahmed , Awad Abeer , Eltatawy Reham
Published: March 2021

Background

Although the frequent respiratory affection in COVID-19, it is well established that it could be presented with a wide variation of gastrointestinal symptoms; however, it is the effect on the pancreas remains unclear.

Case presentation

We report a case of female patient, who was diagnosed with COVID-19 infection. A week later, the patient developed an attack of acute pancreatitis. Other causes of acute pancreatitis were excluded. Therefore, this was attributed to SARS-COV2 infection.

Conclusion

The case raises awareness about the possibility of acute pancreatitis in COVID-19. Also emphasize the importance of measuring serum amylase and lipase in patients with COVID-19.
Outcome of ultrasound-guided, single session pleurodesis in malignant pleural effusion
Authors: Magdy Khalil M. , Hieba Ezzelregal G.
Published: March 2021

Background

Chemical pleurodesis is frequently indicated to relieve symptoms imposed by large/recurrent malignant pleural effusion (MPE). Traditionally, a drain is left in the pleural space till the cessation of fluid accumulation before pleurodesis. Chest ultrasound can detect an amount of pleural fluid as less as 50 ml and can confirm apposition of the pleural surfaces which is required for successful pleurodesis. This work assessed the efficiency and safety of ultrasound-guided, single-session pleurodesis in cases with MPE.

Results

Seventeen of the patients completed a 2-month follow-up. The technique demonstrated a high success rate (88.2%). The mean duration from the start of pleural drainage till pleurodesis was 1.65 ± 0.70 h ranging from 1 to 3 h. A duration of 2.5 h or less was statistically proposed as a cutoff value not to exceed to predict success (sensitivity 100%, specificity 100%). The mean time for total hospital stay related to pleurodesis was 9.88 ± 3.12 h (range 4–12 h). No complications attributed to the procedure were recorded. Pleural Adherence Score and Absent Sliding Score (ASS) had a highly statistically significant correlation (pvalue < 0.001).

Conclusions

An ultrasound-guided completion of the process of pleurodesis in a single session with a shorter duration of pleural fluid drainage and shorter hospital stay (can be done on a day-care basis) is efficient, safe, and cost-effective. This technique is strongly recommended to replace the traditional practice of keeping the indwelling pleural drain for several days waiting for the cessation of pleural fluid reaccumulation. An ultrasound-derived ASS can be used as early as day 1 and day 15 to confirm pleural adherence and to expect the outcome of pleurodesis.
Introduction to this special section: Basin exploration
Authors: Decalf Carole , Molina German
Published: March 2021

Originally, explorers relied on hydrocarbon seeps and 2D seismic lines to define a basin's petroleum potential and to identify its best part. Due to dramatic improvements in seismic technology, today's explorers have access to a vast seismic tool kit, from basin-scale regional 3D seismic surveys to neural network techniques that directly derive reservoir properties from seismic volumes. However, in frontier or mature exploration, geoscientists are often limited by the amount of well data and rock properties information available, and they may deal with poor(er) seismic that makes seismic calibration difficult. Successful explorers will require a lot of knowledge-based creativity to derive meaningful geologic and reservoir properties models to reduce exploration risk. By embracing uncertainties, explorers develop “outside-the-box” thinking to help them chase the hydrocarbon molecules and unlock the prize. With their knowledge in rock physics, subsurface deformation, and wave propagation, geoscientists are deploying new methodologies and tools to fill the data gap and produce an improved description of the subsurface.
Basin-wide empirical rock-physics transform and its application in Campeche Basin
Authors: Liu Yangjun (Kevin) , Casado Jonathan Hernandez , El-Toukhy Mohamed , Tai Shenghong
Published: March 2021

Rock properties in the subsurface are of major importance for evaluating the petroleum prospectivity of a sedimentary basin. The key rock properties to understand are porosity, density, temperature, effective stress, and pore pressure. These rock properties can be obtained or calculated when borehole data are available. However, borehole data are usually sparse, especially in frontier basins. We propose some simple rock-physics transforms for converting P-wave velocity to other rock properties. We found that these rock-physics transforms are predictive in the east and west sides of Campeche Basin. The proposed rock-physics transforms can be used to obtain laterally varying rock properties based on information derived from seismic data.
Lou Sullivan and the Future of Gay Sex
Authors: Martin Ellis , Ozma Zach
Published: March 2021

Editors of the recent publication We Both Laughed in Pleasure: The Selected Diaries of Lou Sullivan consider Sullivan's writing as an assertion of transmasculine embodiment and pleasure in gay sex culture via his “portal to historical thinking.” With intertextual appearances by Ann Cvetkovich, Elizabeth Freeman, John Giorno, Audre Lorde, José Esteban Muñoz, Liam O'Brien, @archivalrival, and a SCRUFF anon.
Does recall time matter in verbal autopsies? Evidence from urban informal settlements in Nairobi, Kenya
Authors: Mategula Donnie , Gichuki Judy
Published: March 2021

Background: To assign a cause of death to non-medically certified deaths, verbal autopsies (VAs) are widely used to determine the cause of death. The time difference between the death and the VA interview, also referred to as recall time, varies depending on social and operational factors surrounding the death. We investigated the effect of recall time on the assignment of causes of death by VA.

Methods: This is a secondary analysis of 2002-2015 survey data of the Nairobi Urban Health Demographic Surveillance System (NUHDSS). The independent variable recall time was derived from the date of death and the date when the VA was conducted. Univariate and multivariate logistic regression methods were used to calculate odds ratios of assigning a cause of death in defined categories of recall time.

Results: There were 6218 deaths followed up between 2002 and 2016, out of which 5495 (88.3%) had VAs done. Recall time varied from 1-3001 days (median  92 days, IQR 44-169 days). Majority of the VAs (45.7%) were conducted between 1-3 months after death. The effect of recall time varied for different diseases. Compared to VAs conducted between 1-3 months, there was a 24% higher likelihood of identifying HIV/AIDS as the cause of death for VAs conducted 4-6 months after death (AOR 1.24; 95% CI 1.01-1.54; p-value = 0.043) and a 40% increased chance of identifying other infectious diseases as the cause of death for VAs conducted <1 month after death (AOR 1.4; 95% CI 1.02-1.92, p-value = 0.024).

Conclusions: Recall time affected the assignment of VA cause of death for HIV/AIDS, other infectious diseases,maternal/neonatal and indeterminate causes. Our analysis indicates that in the urban informal setting, VAs should be conducted from one month up to 6 months after the death to improve the probability of accurately assigning the cause of death.
Problem Drinking Scale (SPP) – psychometrical characteristic
Authors: Kotowska Justyna , Olszewska - Turek Katarzyna , Modrzyński Robert , Celebucka Jolanta , Bętkowska - Korpała Barbara
Published: March 2021

Cel pracy

Cel: Celem pracy jest adaptacja Skali Picia Problemowego (SPP) służącej do ilościowego i jakościowego badania zaburzeń używania alkoholu skonceptualizowanych według klasyfikacji DSM-5.

Metoda

Metoda: Przebadano 708 osób dorosłych, w różnych stopniu spożywających alkohol, w tym 91 leczących się z powodu uzależnienia, których rekrutowano w poradniach leczenia uzależnienia. Pozostałe osoby, o różnej charakterystyce socjodemograficznej, rekrutowano poprzez zastosowanie metody „kuli śnieżnej”. Trafność oceniono przez skorelowanie uzyskanych wyników z testem AUDIT, rzetelność - poprzez analizę zgodności wewnętrznej.

Wyniki

Wyniki: Przedstawiona analiza pokazuje wysoką trafność i rzetelność większości obszarów, co oznacza, że SPP jest narzędziem, które można stosować w praktyce klinicznej. Trafność kryterialną obliczono korelując wyniki SPP z AUDIT (r=0,88, p< ,01). Wyniki w poszczególnych obszarach wahają się od r=0,86 (Trudności w kontroli picia) do r=0,77 (Zależność farmakologiczna). Rzetelność obliczono metodą międzypołówkową, poszczególne wartości współczynników alfa Cronbacha z korektą Spearmana–Browna wahają się w określonych obszarach od 0,89 (Trudności w kontroli picia) do 0,65 (Ryzykowne używanie substancji). W żadnym z obszarów wyniki nie były niższe niż 0,60.

Wnioski

Podsumowanie: SPP jest przydatnym narzędziem badawczym umożliwiającym analizę ilościową i jakościową zaburzeń używania alkoholu. Skala ta jest pomocna w postawieniu pełnej i trafnej diagnozy klinicznej z uwzględnieniem głębokości zaburzenia i w monitorowaniu zmian w procesie terapii.
If It Is Surely Better, Do It More? Implications for Preferences Under Ambiguity
Authors: Ghili Soheil , Klibanoff Peter
Published: March 2021

Consider a canonical problem in choice under uncertainty: choosing from a convex feasible set consisting of all (Anscombe–Aumann) mixtures of two acts f and g, [Formula: see text]. We propose a preference condition, monotonicity in optimal mixtures, which says that surely improving the act f (in the sense of weak dominance) makes the optimal weight(s) on f weakly higher. We use a stylized model of a sales agent reacting to incentives to illustrate the tight connection between monotonicity in optimal mixtures and a monotone comparative static of interest in applications. We then explore more generally the relation between this condition and preferences exhibiting ambiguity-sensitive behavior as in the classic Ellsberg paradoxes. We find that monotonicity in optimal mixtures and ambiguity aversion (even only local to an event) are incompatible for a large and popular class of ambiguity-sensitive preferences (the c-linearly biseparable class. This implies, for example, that maxmin expected utility preferences are consistent with monotonicity in optimal mixtures if and only if they are subjective expected utility preferences. This incompatibility is not between monotonicity in optimal mixtures and ambiguity aversion per se. For example, we show that smooth ambiguity preferences can satisfy both properties as long as they are not too ambiguity averse. Our most general result, applying to an extremely broad universe of preferences, shows a sense in which monotonicity in optimal mixtures places upper bounds on the intensity of ambiguity-averse behavior.

This paper was accepted by Manel Baucells, decision analysis.
Introduction of a virtual trauma meeting in response to COVID-19
Authors: Burchette D , To C , Willmott H
Published: March 2021

Introduction

The COVID-19 pandemic has had a huge impact on all our lives, both personally and professionally, and in many ways has been a catalyst for change. Limitations on social gathering have called the wisdom of a conventional trauma meeting into question. We have initiated our virtual trauma meeting and report our early results.

Materials and methods

Daily morning trauma meetings are now conducted online. Following instigation, we collated the results of a feedback form completed online to assess the relative merits of a virtual trauma meeting.

Results

There were 27 responses received to the electronically administered virtual trauma meeting evaluation survey, from a range of trauma and orthopaedic department personnel. There were no concerns regarding patient safety or decision making and, apart from the quality of the audio (63% dissatisfied or very dissatisfied) positive feedback outweighed negative feedback in every category. At 74%, the majority of respondents were satisfied or very satisfied overall with the virtual trauma meeting.

Conclusion

Trauma meetings can be safely conducted in a virtual environment with high standards of patient care maintained. Virtual trauma meeting offers service enhancements such as early subspecialty input and enhanced cross-site communication and rapid solution development to logistical difficulties. Adapting to conference call etiquette will enhance user experience and opportunity for training opportunities, but adequate investment in high-quality equipment is essential.
Out of hours magnetic resonance imaging for suspected cauda equina syndrome: lessons from a comparative study across two centres
Authors: Silva A , Sachdev B , Kostusiak M , Yousif Mubarak , Flint G , Dhir J , Furtado N , Laing R
Published: March 2021

Background

Cauda equina syndrome, a rare but disabling spinal surgical emergency, requires prompt investigation, ideally using magnetic resonance imaging as patients may require decompressive surgery. Out of hours access to magnetic resonance imaging is only routinely available in major trauma centres and neurosurgical units. Patients in regional hospitals with suspected cauda equina syndrome may require transfer for diagnostic imaging. We retrospectively studied the proportion of patients referred with suspected cauda equina syndrome who required out of hours transfer for magnetic resonance imaging and decompressive surgery.

Materials ands methods

Retrospective cohort study of patients referred using online referral platforms with suspected acute cauda equina syndrome and transferred out of hours between 6pm to 8am on weekdays and all day on weekends to two of the largest neurosurgical units in the UK in Birmingham and Cambridge.

Results

A total of 441 patients were referred across both sites with a suspicion of acute cauda equina syndrome; 339 patients were transferred for diagnostic scans and only 16 of them (4.7%) were positive for cauda equina compression, necessitating prompt decompressive surgery. Of the patients with negative magnetic resonance scans, 50% had their discharge or transfer back to referring hospitals delayed by more than 24 hours.

Conclusions

Over 95% of patients who were transferred for imaging did not undergo emergency decompression. The authors propose a greater role for the provision of out of hours magnetic resonance imaging in all hospitals admitting emergency patients to streamline management.
Single-pixel imaging in the presence of specular reflections
Authors: Ma Mengchao , Sun Qianzhen , Gao Xicheng , Deng Huaxia , Wang Guan , Su Yilong , Guan Qingtian , Zhong Xiang
Published: March 2021

Single-pixel imaging (SPI), which uses a photodetector to detect the reflected total light intensity of a set of structured illumination patterns modulated by a target scene, provides a method for visible waveband imaging, hyperspectral imaging, and terahertz imaging. However, it faces a challenge when the scene to be imaged has specular reflections. To deal with this problem, a multi-angle method without feature matching is presented. With this method, the location of the detector does not affect image reconstruction, and the results of reconstruction at each location are matched at the pixel level automatically. In simulations, with the original image as a reference, the structural similarity index value of the picture obtained by the proposed method is 10% higher than the picture obtained from a single angle. The signal-to-noise ratio value of the picture obtained by the proposed method is 4.424, which is higher than 1.577 of the maximum value of the reconstruction result from a single angle. To evaluate the method, a metal key and an aircraft engine blade with specular reflections are taken as the target scene and are reconstructed from four different imaging perspectives, giving results that are matched at the pixel level. The final reconstructed image is obtained using the principal component analysis algorithm or the fourth-order partial differential equations and principal component analysis algorithm. Compared with the image obtained from a single angle, the correlation coefficient between the image obtained by the proposed method and the reference image is increased from the minimum value of 0.3139 to 0.7050, and the power ratio is increased from 4.52% to 73.63%. The proposed method has great potential specifically for improving the quality of SPI for scenes exhibiting specular reflections.
Compact and low-cost superfluorescent fiber source assisted narrow linewidth Yb-Raman fiber amplifier: publisher’s note
Authors: Song Jiaxin , Lai Wenchang , Ma Pengfei , Xiao Hu , Liu Wei , Zhou Pu
Published: March 2021

This publisher’s note serves to correct the Introduction and Fig. 6 in
Appl. Opt.
60, 1484 (2021)APOPAI0003-693510.1364/AO.413565.
Understanding and optimizing diffraction gratings by the blazing analysis of total internal reflection
Authors: Wu Rong , Sun Mingying , Zhou Shenlei , Zhu Jiangqiang
Published: March 2021

The diffraction grating is a classic and important optical element, and its design usually traverses the whole parameter space to search for an optimal solution, which is time consuming and inefficient. In order to specify the optimization direction of the grating to obtain clearer physical images and to improve the design efficiency, a new blazing model based on the total internal reflection (TIR) is proposed to analyze the diffraction behavior of the grating from a geometry perspective. The optical tunnel along the ridge direction can be used to understand and quantify the blaze of the grating. This TIR blazing model is demonstrated via three types of surface-relief grating with simple formulas, resulting in the solution space decreasing significantly. By utilization of the estimated upper limit of the diffraction efficiency and the range of the depth and slanted angle generated by the TIR blazing model, how the grating delivers the majority of the light energy to a required diffraction order is revealed. Binary and slanted gratings with

>
0.93

efficiency of

T
1

order have been obtained with high probability within the calculated parameter range, regardless of the duty cycle and polarization. The reason why a transmission sawtooth grating cannot blaze the most energy to a high order at normal incidence has been clarified, and the method of using the first or second TIR blaze has also been provided. Through this TIR blazing model, the grating design could be simplified, and accommodation to various application requirements could be optimized as well.
Spectrally resolved point-spread-function engineering using a complex medium
Authors: Boniface Antoine , Mounaix Mickael , Blochet Baptiste , de Aguiar Hilton B. , Quéré Fabien , Gigan Sylvain
Published: March 2021

Propagation of an ultrashort pulse of light through strongly scattering media generates an intricate spatio-spectral speckle that can be described by means of the multi-spectral transmission matrix (MSTM). In conjunction with a spatial light modulator, the MSTM enables the manipulation of the pulse leaving the medium; in particular focusing it at any desired spatial position and/or time. Here, we demonstrate how to engineer the point-spread-function of the focused beam both spatially and spectrally, from the measured MSTM. It consists of numerically filtering the spatial content at each wavelength of the matrix prior to focusing. We experimentally report on the versatility of the technique through several examples, in particular as an alternative to simultaneous spatial and temporal focusing, with potential applications in multiphoton microscopy.
Underwater image enhancement method based on adaptive attenuation-curve prior
Authors: Liu Ke , Liang Yongquan
Published: March 2021

The attenuation (sum of absorption and scattering), which is caused by the dense and non-uniform medium, generally leads to problems of color degradation and detail loss in underwater imaging. In this study, we describe an underwater image enhancement method based on adaptive attenuation-curve prior. This method uses color channel transfer (CCT) to preprocess the underwater images, light smoothing, and wavelength-dependent attenuation to estimate water light and obtain the attenuation ratio between color channels, and estimates and refines the initial relative transmission of the channel. Additionally, the method calculates the attenuation factor and saturation constraints of the three color channels and generates an adjusted reverse saturation map (ARSM) to address uneven light intensity, after which the image is restored through water light and transmission estimation. Furthermore, we applied white balance fusion globally guided image filtering (G-GIF) technology to achieve color enhancement and edge detail preservation in the underwater images. Comparison experiments showed that the proposed method obtained better color and de-hazing effects, as well as clearer edge details, relative to current methods.
Optical-numerical method based on a convolutional neural network for full-field subpixel displacement measurements
Authors: Ma Chaochen , Ren Qing , Zhao Jian
Published: March 2021

The subpixel displacement estimation is an important step to calculation of the displacement between two digital images in optics and image processing. Digital image correlation (DIC) is an effective method for measuring displacement due to its high accuracy. Various DIC algorithms to compare images and to obtain displacement have been implemented. However, there are some drawbacks to DIC. It can be computationally expensive when processing a sequence of continuously deformed images. To simplify the subpixel displacement estimation and to explore a different measurement scheme, a convolutional neural network with a transfer learning based subpixel displacement measurement method (CNN-SDM) is proposed in this paper. The basic idea of the method is to compare images of an object decorated with speckle patterns before and after deformation by CNN, and thereby to achieve a coarse-to-fine subpixel displacement estimation. The proposed CNN is a classification model consisting of two convolutional neural networks in series. The results of simulated and real experiments are shown that the proposed CNN-SDM method is feasibly effective for subpixel displacement measurement due its high efficiency, robustness, simple structure and few parameters.
Tailoring anisotropic absorption in a borophene-based structure via critical coupling
Authors: Liu Tingting , Zhou Chaobiao , Xiao Shuyuan
Published: March 2021

The research of two-dimensional (2D) materials with atomic-scale thicknesses and unique optical properties has become a frontier in photonics and electronics. Borophene, a newly reported 2D material, provides a novel building block for nanoscale materials and devices. We present a simple borophene-based absorption structure to boost the light-borophene interaction via critical coupling in the visible wavelengths. The proposed structure consists of borophene monolayer deposited on a photonic crystal slab backed with a metallic mirror. The numerical simulations and theoretical analysis show that the light absorption of the structure can be remarkably enhanced as high as 99.80% via critical coupling mechanism with guided resonance, and the polarization-dependent absorption behaviors are demonstrated due to the strong anisotropy of borophene. We also examine the tunability of the absorption behaviors by adjusting carrier density and lifetime of borophene, air hole radius in the slab, the incident angle and polarization angle. The proposed absorption structure provides novel access to the flexible and effective manipulation of light-borophene interactions in the visible and shows a good prospect for the future borophene-based electronic and photonic devices.
Compensator design for polarization state management in waveguide displays based on polarization volume gratings
Authors: Feng Xiayu , Lu Lu , Lee Yun-Han , Bos Philip J.
Published: March 2021

In this work, we focus on the polarization state management in optical devices using optical elements based on circular polarization. As an example, we point out the issue in a waveguide display using circular polarization optical elements as input/output couplers, where the polarization state of the light can change as it propagates in the waveguide due to total internal reflection (TIR). This has a negative effect on the waveguide output coupler efficiency, image uniformity, and the polarization multiplexing capability. To address this problem, we discussed two different methods to compensate the polarization state change. With the compensator applied to correct the polarization state change in the waveguide, the optical elements based on circular polarization can be used with their advantages as input/output couplers for waveguide displays.
Analysis of intensity correlation enhanced plasmonic structured illumination microscopy
Authors: Classen Anton , Liu Xinghua , Zheltikov Aleksei M. , Agarwal Girish S.
Published: March 2021

We propose to enhance the performance of localized plasmon structured illumination microscopy (LP-SIM) via intensity correlations. LP-SIM uses sub-wavelength illumination patterns to encode high spatial frequency information. It can enhance the resolution up to three-fold before gaps in the optical transfer function (OTF) support arise. For blinking fluorophores or for quantum antibunching, an intensity correlation analysis induces higher harmonics of the illumination pattern and enlarges the effective OTF. This enables ultrahigh resolutions without gaps in the OTF support, and thus a fully deterministic imaging scheme. We present simulations that include shot and external noise and demonstrate the resolution power under realistic photon budgets. The technique has potential in light microscopy where low-intensity illumination is paramount while aiming for high spatial but moderate temporal resolutions.
Topologically protecting quantum resources with sawtooth lattices
Authors: Zhou Wen-Hao , Wang Xiao-Wei , Gao Jun , Lu Yong-Heng , Jiao Zhi-Qiang , Ren Ruo-Jing , Yang Tian-Huai , Chang Yi-Jun , Jin Xian-Min
Published: March 2021

The inevitable noise and decoherence in the quantum circuit hinder its scalable development, so quantum error correction and quantumness protection for multiple controllable qubits system are necessary. The flatband in the dispersion relation, based on its inherent locality and high degenerate energy band structure, shows non-diffractive transport properties in the line spectrum and has the potential possibility to protect quantum resources in special lattices. The pioneer work has proved that the topologically boundary state is robust to protect the quantumness from disorder and perturbation, which inspires that quantumness can be protected anywhere in a periodic structure, including the boundary state and bulk state. Here, we show the topological protection of quantum resources with different state combinations in a sawtooth lattice. Photons can be localized at any degenerate eigenmode, and the localized effect is determined by only one parameter, without additional modulations. We show a high violation of Cauchy–Schwarz inequality up to 35 standard deviations by measuring cross correlation and auto-correlation of correlated photons. We verify that the topological protection is robust to different wavelengths of correlated photons. Our results suggest an alternative way of exploring topological protection in flatband and bulk state, demonstrating the powerful ability of topological photonics to protect quantum resources.
High-efficiency holographic metacoder for optical masquerade
Authors: Zhao Dong , Dong Zhaogang , Huang Kun
Published: March 2021

Optical masquerades are a low-cost camouflage strategy that avoids the hidden objects to be recognized despite being detected. Here, we demonstrate an optical holography-based masquerade that could encode the camouflaged object (“bomb”) into another uncorrelated phase object (“dog”) by using transmissive dielectric metasurfaces with the total efficiency as high as 78% at visible wavelengths. The phase modulation in the encoded “dog” is realized by changing the inplane orientation of nanostructures. Illuminated by the circularly polarized light, the experimental hologram fabricated by using electron-beam lithography exhibits only the “dog” pattern when observing the surface of sample. To recover the hidden “bomb,” one can observe the holographic image reconstructed at the Fresnel region, which works at the broadband spectrum from 540 nm to 680 nm. Such a technique might find potential applications in information security and military affairs.
Autoencoder based underwater wireless optical communication with high data rate
Authors: Zou Cong , Yang Fang
Published: March 2021

Underwater wireless optical communication (UWOC) has great potential to provide higher data rates and lower time delay communication compared to radio frequency and acoustic counterparts. However, UWOC systems with wide bandwidths are subject to photon absorption and scattering, which result in severe energy loss for optical beams and inter-symbol interference. To overcome these issues, this Letter interprets the UWOC system as an autoencoder (AE), named UWOC-AE, which takes advantage of the double Gamma function approximating channel impulse response of underwater optical links to learn the channel characteristics. Thus, within the AE framework, the encoder and decoder can be optimized jointly. Experiments indicate that the proposed UWOC-AE can achieve superior performance with high data rates compared to existing techniques.
Effect of indium pre-flow on wavelength shift and crystal structure of deep green light emitting diodes
Authors: Abdul Rais Shamsul Amir , Hassan Zainuriah , Abu Bakar Ahmad Shuhaimi , Abd Rahman Mohd Nazri , Yusuf Yusnizam , Md Taib Muhamad Ikram , Sulaiman Abdullah Fadil , Hussin Hayatun Najiha , Ahmad Mohd Fairus , Norizan Mohd Natashah , Nagai Keiji , Akimoto Yuka , Shoji Dai
Published: March 2021

To produce a deep green (530 nm–570 nm) LED, the suitable indium (In) composition in the InxGa1-xN/GaN multi-quantum well (MQW) structure is crucial because a lower indium composition will shift the wavelength of emission towards the ultraviolet region. In this paper, we clarify the effects of an indium-rich layer to suppress such blue shifting, especially after the annealing process. According to characterizations by the uses of XRD and TEM, narrowing of the MQW layer was observed by the indium capping, while without the capping, the annealing results in a slight narrowing of MQW on the nearest layer to the p-type layer. By adding an indium capping layer, the blue shift of the photoluminescence was also suppressed and a slight red shift to keep green emission was observed. Such photoluminescence properties were consistent with the tiny change of the MQW as seen in the XRD and TEM characterizations.
Filamentary damage of fused silica irradiated by a 532 nm nanosecond laser
Authors: Cao Jingrui , Jiang Yong , Qiu Rong , Lü Tao
Published: March 2021

In this study, we use a time-resolved pump-probe shadowgraph technique to investigate the evolution characteristics of filamentary damage in bulk fused silica induced by a nanosecond pulse at 532 nm. The pump laser focuses on the front surface of sample and filamentary damage appears independently in the middle of sample. The whole damage process can be divided into single filament (SF), double filaments (DFs), and long filament (LF) successively. At the same time, the improved moving focus model is proposed by taking into account the temporal shape of the laser pulse and the laser is blocked and reflected by plasma at the critical density. It is in good agreement with the experimental result of filamentary damage process and helps to explore the mechanism of laser-induced filamentary damage in nanosecond regime.
Success of prophylactic antiviral therapy for SARS-CoV-2: Predicted critical efficacies and impact of different drug-specific mechanisms of action
Authors: Czuppon Peter , Débarre Florence , Gonçalves Antonio , Tenaillon Olivier , Perelson Alan S. , Guedj Jérémie , Blanquart François
Published: March 2021

Repurposed drugs that are safe and immediately available constitute a first line of defense against new viral infections. Despite limited antiviral activity against SARS-CoV-2, several drugs are being tested as medication or as prophylaxis to prevent infection. Using a stochastic model of early phase infection, we evaluate the success of prophylactic treatment with different drug types to prevent viral infection. We find that there exists a critical efficacy that a treatment must reach in order to block viral establishment. Treatment by a combination of drugs reduces the critical efficacy, most effectively by the combination of a drug blocking viral entry into cells and a drug increasing viral clearance. Below the critical efficacy, the risk of infection can nonetheless be reduced. Drugs blocking viral entry into cells or enhancing viral clearance reduce the risk of infection more than drugs that reduce viral production in infected cells. The larger the initial inoculum of infectious virus, the less likely is prevention of an infection. In our model, we find that as long as the viral inoculum is smaller than 10 infectious virus particles, viral infection can be prevented almost certainly with drugs of 90% efficacy (or more). Even when a viral infection cannot be prevented, antivirals delay the time to detectable viral loads. The largest delay of viral infection is achieved by drugs reducing viral production in infected cells. A delay of virus infection flattens the within-host viral dynamic curve, possibly reducing transmission and symptom severity. Thus, antiviral prophylaxis, even with reduced efficacy, could be efficiently used to prevent or alleviate infection in people at high risk.
Mediterranean diet assessment challenges: Validation of the Croatian Version of the 14-item Mediterranean Diet Serving Score (MDSS) Questionnaire
Authors: Marendić Mario , Polić Nikolina , Matek Helena , Oršulić Lucija , Polašek Ozren , Kolčić Ivana
Published: March 2021

Mediterranean diet (MD) is among the most commonly investigated diets and recognized as one of the healthiest dietary patterns. Due to its complexity, geographical and cultural variations, it also represents a challenge for quantification. The aim of this cross-sectional study was to assess reliability and validity of the Croatian version of the 14-item Mediterranean Diet Serving Score (MDSS), using the Mediterranean Diet Adherence Screener (MEDAS) as the referent test. We included the exploratory sample of 360 medical students, and a confirmatory sample of 299 health studies students from the University of Split, Croatia. Test-retest reliability and validity of the MDSS were tested using intra-class correlation coefficients (ICC), while Cohen’s kappa statistic was used to test correct classification of subjects into MD adherent/non-adherent category. A very good reliability was shown for the overall MDSS score (ICC = 0.881 [95% CI 0.843–0.909]), and a moderate reliability for the binary adherence (κ = 0.584). Concurrent validity of the MDSS was also better when expressed as a total score (ICC = 0.544 [0.439–0.629]) as opposed to the adherence (κ = 0.223), with similar result in the confirmatory sample (ICC = 0.510 [0.384–0.610]; κ = 0.216). Disappointingly, only 13.6% of medical students were adherent to the MD according to MDSS, and 19.7% according to the MEDAS questionnaire. Nevertheless, MDSS score was positively correlated with age (ρ = 0.179: P = 0.003), self-assessed health perception (ρ = 0.123; P = 0.047), and mental well-being (ρ = 0.139: P = 0.022). MDSS questionnaire is a short, reliable and reasonably valid instrument, and thus useful for assessing the MD adherence, with better results when used as a numeric score, even in the population with low MD adherence.
Long-term monitoring of margays (Leopardus wiedii): Implications for understanding low detection rates
Authors: Harmsen Bart J. , Saville Nicola , Foster Rebecca J.
Published: March 2021

Population assessments of wide-ranging, cryptic, terrestrial mammals rely on camera trap surveys. While camera trapping is a powerful method of detecting presence, it is difficult distinguishing rarity from low detection rate. The margay (Leopardus wiedii) is an example of a species considered rare based on its low detection rates across its range. Although margays have a wide distribution, detection rates with camera traps are universally low; consequently, the species is listed as Near Threatened. Our 12-year camera trap study of margays in protected broadleaf forest in Belize suggests that while margays have low detection rate, they do not seem to be rare, rather that they are difficult to detect with camera traps. We detected a maximum of 187 individuals, all with few or no recaptures over the years (mean = 2.0 captures/individual ± SD 2.1), with two-thirds of individuals detected only once. The few individuals that were recaptured across years exhibited long tenures up to 9 years and were at least 10 years old at their final detection. We detected multiple individuals of both sexes at the same locations during the same survey, suggesting overlapping ranges with non-exclusive territories, providing further evidence of a high-density population. By studying the sparse annual datasets across multiple years, we found evidence of an abundant margay population in the forest of the Cockscomb Basin, which might have been deemed low density and rare, if studied in the short term. We encourage more long-term camera trap studies to assess population status of semi-arboreal carnivore species that have hitherto been considered rare based on low detection rates.
Spatial analysis of COVID-19 incidence and the sociodemographic context in Brazil
Authors: Raymundo Carlos Eduardo , Oliveira Marcella Cini , Eleuterio Tatiana de Araujo , André Suzana Rosa , da Silva Marcele Gonçalves , Queiroz Eny Regina da Silva , Medronho Roberto de Andrade
Published: March 2021

Background

Identified in December 2019 in the city of Wuhan, China, the outbreak of COVID-19 spread throughout the world and its impacts affect different populations differently, where countries with high levels of social and economic inequality such as Brazil gain prominence, for understanding of the vulnerability factors associated with the disease. Given this scenario, in the absence of a vaccine or safe and effective antiviral treatment for COVID-19, nonpharmacological measures are essential for prevention and control of the disease. However, many of these measures are not feasible for millions of individuals who live in territories with increased social vulnerability. The study aims to analyze the spatial distribution of COVID-19 incidence in Brazil’s municipalities (counties) and investigate its association with sociodemographic determinants to better understand the social context and the epidemic’s spread in the country.

Methods

This is an analytical ecological study using data from various sources. The study period was February 25 to September 26, 2020. Data analysis used global regression models: ordinary least squares (OLS), spatial autoregressive model (SAR), and conditional autoregressive model (CAR) and the local regression model called multiscale geographically weighted regression (MGWR).

Findings

The higher the GINI index, the higher the incidence of the disease at the municipal level. Likewise, the higher the nurse ratio per 1,000 inhabitants in the municipalities, the higher the COVID-19 incidence. Meanwhile, the proportional mortality ratio was inversely associated with incidence of the disease.

Discussion

Social inequality increased the risk of COVID-19 in the municipalities. Better social development of the municipalities was associated with lower risk of the disease. Greater access to health services improved the diagnosis and notification of the disease and was associated with more cases in the municipalities. Despite universal susceptibility to COVID-19, populations with increased social vulnerability were more exposed to risk of the illness.
On the joint role of non-Hispanic Black race/ethnicity and weight status in predicting postmenopausal weight gain
Authors: Ford Christopher N. , Chang Shine , Wood Alexis C. , Manson JoAnn E. , Garcia David O. , Laroche Helena , Bird Chloe E. , Vitolins Mara Z.
Published: March 2021

Objectives

To determine how baseline weight status contributes to differences in postmenopausal weight gain among non-Hispanic Blacks (NHBs) and non-Hispanic Whites (NHWs).

Methods

Data were included from 70,750 NHW and NHB postmenopausal women from the Women’s Health Initiative Observational Study (WHI OS). Body Mass Index (BMI) at baseline was used to classify women as having normal weight, overweight, obese class I, obese class II or obese class III. Cox proportional hazards was used to estimate the hazard of a 10% or more increase in weight from baseline.

Results

In both crude and adjusted models, NHBs were more likely to experience ≥10% weight gain than NHWs within the same category of baseline weight status. Moreover, NHBs who were normal weight at baseline were most likely to experience ≥10% weight gain in both crude and adjusted models. Age-stratified results were consistent with overall findings. In all age categories, NHBs who were normal weight at baseline were most likely to experience ≥10% weight gain. Based on the results of adjusted models, the joint influence of NHB race/ethnicity and weight status on risk of postmenopausal weight gain was both sub-additive and sub-multiplicative.

Conclusion

NHBs are more likely to experience postmenopausal weight gain than NHWs, and the disparity in risk is most pronounced among those who are normal weight at baseline. To address the disparity in postmenopausal obesity, future studies should focus on identifying and modifying factors that promote weight gain among normal weight NHBs.
The allelic rice immune receptor Pikh confers extended resistance to strains of the blast fungus through a single polymorphism in the effector binding interface
Authors: De la Concepcion Juan Carlos , Maidment Josephine H. R. , Longya Apinya , Xiao Gui , Franceschetti Marina , Banfield Mark J.
Published: March 2021

Arms race co-evolution drives rapid adaptive changes in pathogens and in the immune systems of their hosts. Plant intracellular NLR immune receptors detect effectors delivered by pathogens to promote susceptibility, activating an immune response that halts colonization. As a consequence, pathogen effectors evolve to escape immune recognition and are highly variable. In turn, NLR receptors are one of the most diverse protein families in plants, and this variability underpins differential recognition of effector variants. The molecular mechanisms underlying natural variation in effector recognition by NLRs are starting to be elucidated. The rice NLR pair Pik-1/Pik-2 recognizes AVR-Pik effectors from the blast fungus Magnaporthe oryzae, triggering immune responses that limit rice blast infection. Allelic variation in a heavy metal associated (HMA) domain integrated in the receptor Pik-1 confers differential binding to AVR-Pik variants, determining resistance specificity. Previous mechanistic studies uncovered how a Pik allele, Pikm, has extended recognition to effector variants through a specialized HMA/AVR-Pik binding interface. Here, we reveal the mechanistic basis of extended recognition specificity conferred by another Pik allele, Pikh. A single residue in Pikh-HMA increases binding to AVR-Pik variants, leading to an extended effector response in planta. The crystal structure of Pikh-HMA in complex with an AVR-Pik variant confirmed that Pikh and Pikm use a similar molecular mechanism to extend their pathogen recognition profile. This study shows how different NLR receptor alleles functionally converge to extend recognition specificity to pathogen effectors.