bluuebunny/crossref_metadata_2025 huggingface dataset:
A neurologist’s perspective on serum neurofilament light in the memory clinic: a prospective implementation study
Authors: Willemse E. A. J. , Scheltens P. , Teunissen C. E. , Vijverberg E. G. B.
Published: May 2021

Background

Neurofilament light in serum (sNfL) is a biomarker for axonal damage with elevated levels in many neurological disorders, including neurodegenerative dementias. Since within-group variation of sNfL is large and concentrations increase with aging, sNfL’s clinical use in memory clinic practice remains to be established. The objective of the current study was to evaluate the clinical use of serum neurofilament light (sNfL), a cross-disease biomarker for axonal damage, in a tertiary memory clinic cohort.

Methods

Six neurologists completed questionnaires regarding the usefulness of sNfL (n = 5–42 questionnaires/neurologist). Patients that visited the Alzheimer Center Amsterdam for the first time between May and October 2019 (n = 109) were prospectively included in this single-center implementation study. SNfL levels were analyzed on Simoa and reported together with normal values in relation to age, as part of routine diagnostic work-up and in addition to cerebrospinal fluid (CSF) biomarker analysis.

Results

SNfL was perceived as useful in 53% (n = 58) of the cases. SNfL was more often perceived as useful in patients < 62 years (29/48, 60%, p = 0.05) and males (41/65, 63%, p < 0.01). Availability of CSF biomarker results at time of result discussion had no influence. We observed non-significant trends for increased perceived usefulness of sNfL for patients with the diagnosis subjective cognitive decline (64%), psychiatric disorder (71%), or uncertain diagnosis (67%). SNfL was mostly helpful to neurologists in confirming or excluding neurodegeneration. Whether sNfL was regarded as useful strongly depended on which neurologist filled out the questionnaire (ranging from 0 to 73% of useful cases/neurologist).

Discussion

Regardless of the availability of CSF biomarker results, sNfL was perceived as a useful tool in more than half of the evaluated cases in a tertiary memory clinic practice. Based on our results, we recommend the analysis of the biomarker sNfL to confirm or exclude neurodegeneration in patients below 62 years old and in males.
Immunotherapy in Multiple Myeloma—Time for a Second Major Paradigm Shift
Authors: Mohan Meera , Hari Parameswaran , Dhakal Binod
Published: May 2021

Multiple myeloma (MM) is a genetically heterogenous disease and remains mostly incurable with a small group of patients achieving long-term disease remission. The past decade witnessed enormous efforts to break the circulus vitiosus of tumor-induced immunosuppression and to re-engage the immune system to fight cancer. The first-in-class anti-CD38 monoclonal antibody, daratumumab, has shown unprecedented responses especially in combination with other novel agents in both newly diagnosed and relapsed MM. There has been great interest in harnessing the power of T cells with bispecific antibodies and chimeric antigen receptor T-cell therapies in hematologic malignancies including MM. These immune-based approaches have shown notable antimyeloma effects with deeper, durable responses in early clinical trials of heavily pretreated patients with MM with limited therapeutic options. Several trials are underway investigating both single and combinatorial immune therapies at different stages with a hope to bring major transformation in MM. In the current review, we summarize how an immunologic approach offers promise for the treatment of MM and is setting the stage for second major paradigm shift 2 decades after the emergence of thalidomide and novel therapeutics.
A Systematic Approach in the Development of the Morphologically-Directed Raman Spectroscopy Methodology for Characterizing Nasal Suspension Drug Products
Authors: Farias Gonçalo , Shur Jagdeep , Price Robert , Bielski Elizabeth , Newman Bryan
Published: May 2021

Demonstrating bioequivalence (BE) of nasal suspension sprays is a challenging task. Analytical tools are required to determine the particle size of the active pharmaceutical ingredient (API) and the structure of a relatively complex formulation. This study investigated the utility of the morphologically-directed Raman spectroscopy (MDRS) method to investigate the particle size distribution (PSD) of nasal suspensions. Dissolution was also investigated as an orthogonal technique. Nasal suspension formulations containing different PSD of mometasone furoate monohydrate (MFM) were manufactured. The PSD of the MFM batches was characterized before formulation manufacture using laser diffraction and automated imaging. Upon formulation manufacture, the droplet size, single actuation content, spray pattern, plume geometry, the API dissolution rate, and the API PSD by MDRS were determined. A systematic approach was utilized to develop a robust method for the analysis of the PSD of MFM in Nasonex® and four test formulations containing the MFM API with different particle size specifications. Although the PSD between distinct techniques cannot be directly compared due to inherent differences between these methodologies, the same trend is observed for three out of the four batches. Dissolution analysis confirmed the trend observed by MDRS in terms of PSD. For suspension-based nasal products, MDRS allows the measurement of API PSD which is critical for BE assessment. This approach has been approved for use in lieu of a comparative clinical endpoint BE study [1]. The correlation observed between PSD and dissolution rate extends the use of dissolution as a critical analytical tool demonstrating BE between test and reference products.
In The Wake of Okwui Enwezor
Authors: Becker Natasha
Published: May 2021

This article takes a critical and intimate look at Okwui Enwezor’s work in South Africa during the 1990s and asserts that the international exhibition he curated in Johannesburg in 1997—the Second Johannesburg Biennale, Trade Routes: History and Geography—is an important lens through which to explore Africa’s entangled histories. Trade Routes mattered as much for the discourse it produced as for the artworks it presented. The exhibition checklist features extraordinary works that were made between 1989 and 1997 by artists whose critical acclaim we take for granted today but who were at that time still underappreciated or emerging. Trade Routes not only challenged the status of the existing canon on African art but also proposed a new counter-canon. Additionally, Trade Routes and Enwezor’s concept of the meeting of worlds might have greater analytical potential as a metaphor for the meeting point of two indecipherable South Africas. Under apartheid, Johannesburg was two “countries,” and people lived in two different realities, depending on one’s history, geography, race, ethnicity, class, gender, culture, education, and opportunities. Enwezor constantly confronted the legacy of racism in small and big ways in South Africa. He was at the center of critical debates about race and representation. While there are all kinds of practical guidelines for how to talk about racism within the larger culture, we still do not have one for talking about racial inequality and racism in institutions, exhibition histories, curatorial practice, and the commercial art world. Instead, we have Okwui Enwezor to accompany us on our quest and to remind us to keep consulting both histories and imaginaries, theories and practices, and to continue to interrogate how cycles are reproduced or radically ruptured.
Electronic methodical manual «Methodological guidelines for the implementation of practical classes in the discipline "Environmental law" for students of the specialty 40.02.02 "Law enforcement" of secondary vocational education institutions»
Authors: GONCHAROVA OKSANA
Published: May 2021

Guidelines for the implementation of practical classes in the discipline " Environmental Law "are intended for students of the specialty 40.02.02" Law enforcement " of secondary vocational education institutions. The purpose of the guidelines is to provide a clear organization of practical classes in the discipline, to create an opportunity for students who were absent from the practical lesson to independently perform the work, to issue a report and to protect the work in a timely manner.
Model for the Dynamics of the Gas Medium Temperature Growth in the Initial Stage of a Fire in Buildings
Authors: Fedorov Yu. , Pavlidis V. , Urban V. , Yakovleva E.
Published: May 2021

Within the framework of the integral mathematical model for the building fire’s initial stage, the increments of the gas medium temperature in the initial stage of a fire development in buildings have been determined, and estimates for these increments have been presented. The dependence between the gas medium temperature’s relative increment and the burn-up rate’s average value has been established, and an estimated formula for the relative temperature difference over a given time period has been obtained.
Model for the Suspensions Separation Process in Hydrodynamic Filters with a Rotating Filter Element
Authors: Devisilov Vladimir , Lvov V. , Sharay E.
Published: May 2021

The possibility of applying the probabilistic-statistical method for theoretical calculation of characteristics related to suspensions separation in self-cleaning hydrodynamic filters with a rotating filter element has been demonstrated. It has been shown that the change in characteristics of the suspensions separation in hydrodynamic filters with a rotating filter element can be satisfactorily described based on equations of diffusion type, in particular, using the Fokker–Planck–Kolmogorov equation. The main parameters of the separation process in hydrodynamic filters with a rotating filter element have been determined.
La aljama cristianizada de Baeza en el siglo XIII, primera catedral de Andalucía.
Authors: Rueda Galán Luis
Published: May 2021

Historiador del Arte. Actualmente cursa el doctorado en la Univerisdad de Jaén en cotutela con la École pratique des hautes études de París (Université PSL). Contratado del programa FPU del Ministerio de Educación, ha realizado estancias de investigación en el Kunsthistorisches Institut – Max Planck Institut de Florencia, en el Departamento de Arquitectura de la Universidad de Florencia y en el Archivo Apostólico Vaticano. Sus trabajos se centran en el estudio de las transferencias en el arte y la arquitectura de las tres grandes religiones monoteístas del área mediterránea durante la Baja Edad Media y principios de la Moderna.
Smoking cessation and serious mental illness
Authors: Cope Graham
Published: May 2021

Graham Cope explains how people with mental health conditions can be encouraged to quit smoking
Automatic optical inspection platform for real-time surface defects detection on plane optical components based on semantic segmentation
Authors: Karangwa Jules , Kong Linghua , Yi Dingrong , Zheng Jishi
Published: May 2021

The tendency to increase the accuracy and quality of optical parts
inspection can be observed all over the world. The imperfection of
manufacturing techniques can cause different defects on the optical
component surface, making surface defects inspection a crucial part of
the manufacturing of optical components. Currently, the inspection of
lenses, filters, mirrors, and other optical components is performed by
human inspectors. However, human-based inspections are time-consuming,
subjective, and incompatible with a highly efficient high-quality
digital workflow. Moreover, they cannot meet the complex criteria of
ISO 10110-7 for the quality pass and fail optical element samples. To
meet the high demand for high-quality products, intelligent visual
inspection systems are being used in many manufacturing processes.
Automated surface imperfection detection based on machine learning has
become a fascinating and promising area of research, with a great
direct impact on different visual inspection applications. In this
paper, an optical inspection platform combining parallel deep
learning–based image-processing approaches with a high-resolution
optomechanical module was developed to detect surface defects on
optical plane components. The system involves the mechanical modules,
the illumination and imaging modules, and the machine vision
algorithm. Dark-field images were acquired using a

2448

×

2048

-pixel line-scanning CMOS camera with
3.45 µm per-pixel resolution. Convolutional neural networks and
semantic segmentation were used for a machine vision algorithm to
detect and classify defects on captured images of optical bandpass
filters. The experimental results on different bandpass filter samples
have shown the best performance compared to traditional methods by
reaching an impressive detection speed of 0.07 s per image and an
overall detection pixel accuracy of 0.923.
Aerial holographic 3D display with an enlarged field of view by the time-division method
Authors: Sando Yusuke , Barada Daisuke , Yatagai Toyohiko
Published: May 2021

We propose a method to enlarge the field of view (FOV) of holographic 3D displays in both the horizontal and vertical directions. The FOV was enlarged by using two galvano mirrors and a high-speed spatial light modulator. These optical elements were placed so that the imaging relation was satisfied among them and they were synchronously driven at a high speed to implement the time-division method. Using this method, a floating 3D object could be successfully reconstructed in mid-air near the focal point of the final lens at the rate of 10 Hz. The FOV was enlarged five times and two times in the horizontal and vertical directions, respectively.
MIMONet: Structured-light 3D shape reconstruction by a multi-input multi-output network
Authors: Nguyen Hieu , Ly Khanh L. , Nguyen Thanh , Wang Yuzheng , Wang Zhaoyang
Published: May 2021

Reconstructing 3D geometric representation of objects with deep learning frameworks has recently gained a great deal of interest in numerous fields. The existing deep-learning-based 3D shape reconstruction techniques generally use a single red–green–blue (RGB) image, and the depth reconstruction accuracy is often highly limited due to a variety of reasons. We present a 3D shape reconstruction technique with an accuracy enhancement strategy by integrating the structured-light scheme with deep convolutional neural networks (CNNs). The key idea is to transform multiple (typically two) grayscale images consisting of fringe and/or speckle patterns into a 3D depth map using an end-to-end artificial neural network. Distinct from the existing autoencoder-based networks, the proposed technique reconstructs the 3D shape of target using a refinement approach that fuses multiple feature maps to obtain multiple outputs with an accuracy-enhanced final output. A few experiments have been conducted to verify the robustness and capabilities of the proposed technique. The findings suggest that the proposed network approach can be a promising 3D reconstruction technique for future academic research and industrial applications.
Optimization-based optical diffraction tomography using iODT initialization
Authors: Fan Shengli , Smith-Dryden Seth , Li Guifang , Saleh Bahaa
Published: May 2021

Optical diffraction tomography (ODT) is a label-free and noninvasive
technique for biological imaging. However, ODT is only applicable to
weakly scattering objects. To extend ODT to the multiple-scattering
regime, more advanced inversion algorithms have been developed,
including optimization-based ODT (Opti-ODT) and iterative ODT (iODT).
In this paper, we propose a combined strategy, namely, an iODT
initialization for Opti-ODT, based on the observed complementarity of
their individual advantages. This study numerically demonstrates that
under this combined strategy, the reconstruction can accurately
converge to a better local minimum, especially in the case of multiply
scattering objects with large optical path differences.
Incoherent digital holography simulation based on scalar diffraction theory
Authors: Nobukawa Teruyoshi , Katano Yutaro , Goto Masahide , Muroi Tetsuhiko , Kinoshita Nobuhiro , Iguchi Yoshinori , Ishii Norihiko
Published: May 2021

Incoherent digital holography (IDH) enables passive 3D imaging through the self-interference of incoherent light. IDH imaging properties are dictated by the numerical aperture and optical layout in a complex manner [Opt. Express 27, 33634 (2019)OPEXFF1094-408710.1364/OE.27.033634]. We develop an IDH simulation model to provide insight into its basic operation and imaging properties. The simulation is based on the scalar diffraction theory. Incoherent irradiance and self-interference holograms are numerically represented by the intensity-based summation of each propagation through finite aperture optics from independent point sources. By comparing numerical and experimental results, the applicability, accuracy, and limitation of the simulation are discussed. The developed simulation would be useful in optimizing the IDH setup.
Measuring the complex forward-scattering amplitude of single particles by self-reference interferometry: CAS-v1 protocol
Authors: Moteki Nobuhiro
Published: May 2021

Theoretical and experimental bases are given for measuring the complex forward-scattering amplitude of single particles through self-reference interferometry. Our analyses reveal the nondimensional parameters that primarily control the accuracy and resolution of the complex amplitude data. We propose a measurement protocol, Complex Amplitude Sensing version 1 (CAS-v1), for effectively utilizing self-reference interferometry as a universal tool for inline measurements of the complex forward-scattering amplitude of single sub- and super-micron particles suspended in a fluid flow. The CAS-v1 protocol will facilitate applications of self-reference interferometry to real-time particle measurements in the industrial, biomedical, and environmental sciences.
Calibration of the laser pointing bias of the GaoFen-7 satellite based on simulation waveform matching
Authors: Liu Ren , Xie Junfeng
Published: May 2021

The two-beam GaoFen-7 (GF-7) laser altimeter is China's first formal spaceborne laser altimeter system for Earth observations. In this article, a calibration method based on simulation waveform matching is proposed to correct the laser pointing error now that the satellite is in orbit. In the method, the optimal position of the laser footprint is searched using simulated and actual waveforms. Then, the laser pointing is calibrated based on the laser footprint optimal position. In this paper, after calibration of the GF-7 laser pointing, infrared detectors are used to capture laser footprints for accuracy verification. The results show that the GF-7 laser pointing accuracy is greatly improved by the method; the laser pointing accuracy of beam 1 is approximately 5.4 arcsec, and that of beam 2 is approximately 5.7 arcsec. Subsequently, two laser footprints are selected for GF-7 laser calibration in the Helan Mountains, China, and AW3D30 digital surface model (DSM) and GPS/RTK data are used to verify the laser elevation measurement accuracy (EMA). The results show that the EMA of the GF-7 laser is significantly improved after calibration. Over flat terrain, the EMA of the GF-7 laser is improved by 10 times, from 3.74 ± 0.55 m to 0.35 ± 0.50 m, verifying the effectiveness of the proposed method.
Simple way to correct the drift in surface-coupled optical tweezers using the laser reflection pattern
Authors: Liu Wenzhao , Zhong Zhensheng , Ma Jie
Published: May 2021

The surface-coupled optical tweezers are widely used to resolve small units of motion in biology. However, such motions could readily be interfered by the drift between the trap and surface. We present a simple and low-cost method to correct the drift both actively and passively based on video tracking the distance between the laser reflection pattern and the reference bead. As a result, we achieved sub-nanometer resolution and stability for the stuck bead over a broad range of averaging time (0.002-100 s) as demonstrated by the Allan deviation analysis. The sub-nanometer resolution was further manifested with step measurement. Finally, in double-stranded DNA and DNA hairpin stretching experiments, an extension resolution of 1-2 nm with the stability over 120 s has been demonstrated under a constant force. This work thus provides an easy way to bring the benefit of nanometer resolution and long-term stability to the surface-coupled optical tweezers.
Dynamic reflective color pixels based on molybdenum oxide
Authors: Santos G. , Gonzalez F. , Ortiz D. , Saiz J. M. , Losurdo M. , Moreno F. , Gutierrez Y.
Published: May 2021

Active materials which show phase transitions, usually known as Phase Change Materials (PCM), have paved the way to a new generation of reconfigurable plasmonic platforms. Tunable color devices have experienced a great development in the recent years. In particular, reflective color filters can take advantage from sunlight to select and reflect a specific resonant wavelength in the visible spectrum range. Reflective displays are usually structural color filters based on asymmetric Fabry-Perot cavities (AFPCs). For a fixed geometry, most of AFPCs filters generate static color, limiting their potential as tunable color devices. Dynamic color is achieved by introducing an active layer whose optical properties can be modulated by an external stimuli. In this paper, we propose AFPCs based on molybdenum oxide (MoO
x
, 2<x<3) to achieve switchable on/off color reflective pixels. On and off states of the pixels are controlled through the stoichiometry of the MoO
x
layer.
Sub-Nyquist ghost imaging by optimizing point spread function
Authors: Gong Wenlin
Published: May 2021

Point spread function (PSF) of ghost imaging (GI) with pseudo-thermal light source doesn’t satisfy the property of space translation invariance and existing GI linear reconstruction algorithms offer images with low quality when the measurement process doesn’t reach ergodic. By modifying the intensity value of the speckle patterns recorded by the camera in the reference path, the property of PSF can be optimized and a linear reconstruction method called optimized ghost imaging (OGI) is proposed to stably recover the object’s image even in the measurements below Nyquist limit. In comparison with existing GI linear reconstruction algorithms, both the simulated and experimental results demonstrate that the image’s SNR can be significantly enhanced by OGI especially when the sampling ratio is larger than 0.68 and the detection SNR is greater than 20 dB.
Development of terahertz two-dimensional phase gratings for multiple beam generation based on a high-accuracy phase retrieval algorithm
Authors: Ren Yuan , Xie GuoAo , Zhang YiLong , Liu Dong , Zhou KangMin , Miao Wei , Zhang Wen , Shi ShengCai
Published: May 2021

High efficiency and accuracy phase gratings are of crucial importance for large format heterodyne array receivers at terahertz frequencies. Here, by developing a design approach that can create gratings with arbitrary two-dimensional diffraction distributions, we have realized a reflective metallic phase grating that generates 2×2 diffraction beams at 0.85 THz. The measured total power efficiency of the diffraction beam pattern is 81.9%, which demonstrates at least 17% improvement in efficiency compared with the standard pseudo-2D Fourier phase grating. In addition, we report the realization of up to 10×10 diffraction beam two-dimensional phase grating designs at terahertz wavelengths, using an adaptation of the Gerchberg-Saxton (GS) scheme known as the Mixed-Region-Amplitude-Freedom algorithm. Rigorous full wave simulation proves the efficiency and accuracy of the design, which overcomes the inaccurate intensity of the beam distribution drawbacks originated from the standard GS algorithm. The results pave the way for the development of large-pixel terahertz multi-beam heterodyne receivers.
Study of a laser echo in an inhomogeneous dust environment with a continuous field Monte Carlo radiative transfer model
Authors: Bao Jiaqian , Zha Bingting , Xu Chenyoushi , Zhang He
Published: May 2021

A continuous field Monte Carlo radiative transfer model with an improved semianalytic approach is developed to study laser propagation in an inhomogeneous dust environment. In the proposed model, the photon step size can vary with the mass concentration of the dust environment. Additionally, the scattering properties of the dust particles are calculated with the T-matrix method and the T-matrix scattering phase function is applied to the Monte Carlo simulation with a rejection method. Using this model, the influences of the particle sizes and shapes on the backscattering properties are studied. Finally, the laser echoes simulated by our proposed model are compared with those of traditional Monte Carlo method and experimental results. Different mass concentration distributions indeed influence the simulated laser echo. The simulated results (of our proposed model) agree well with the measured data, demonstrating the effectiveness and accuracy of our approach for inhomogeneous media.
Uniform and efficient beam shaping for high-energy lasers
Authors: Ackermann Lisa , Roider Clemens , Schmidt Michael
Published: May 2021

Phase-only beam shaping with liquid crystal on silicon spatial light modulators (SLM) allows modulating the wavefront dynamically and generating arbitrary intensity patterns with high efficiency. Since this method cannot take control of all degrees of freedom, a speckle pattern appears and drastically impairs the outcome. There are several methods to overcome this issue including algorithms which directly control phase and amplitude, but they suffer from low efficiency. Methods using two SLMs yield excellent results but they are usually limited in the applicable energy due to damage to the SLM’s backplane. We present a method which makes use of two SLMs and simultaneously gives way for high-energy laser applications. The algorithm and setup are designed to keep the fluence on the SLMs low by distributing the light over a large area. This provides stability against misalignment and facilitates experimental feasibility while keeping high efficiency.
Influence of seed layers on the reflectance of sputtered aluminum thin films
Authors: Schmitt Paul , Stempfhuber Sven , Felde Nadja , Szeghalmi Adriana V. , Kaiser Norbert , Tünnermann Andreas , Schwinde Stefan
Published: May 2021

The fabrication of highly reflective aluminum coatings is still an important part of current research due to their high intrinsic reflectivity in a broad spectral range. By using thin seed layers of Cu, CuOx, Cr, CrOx, Au, and Ag, the morphology of sputtered (unprotected) aluminum layers and, consequently, their reflectance can be influenced. In this long-term study, the reflectance behavior was measured continuously using spectrophotometry. Particular seed layer materials enhance the reflectance of aluminum coatings significantly and reduce their long-term degradation. Combining such seed layers with evaporation processes and suitable protective layers could further increase the reflectance of aluminum coatings.
C and L band room-temperature continuous-wave InP-based microdisk lasers grown on silicon
Authors: Lin Liying , Xue Ying , Li Jie , Luo Wei , Huang Jie , Lau Kei May
Published: May 2021

Quantum-dot (QD) and quantum-dash (QDash) have been shown to be promising gain materials for lasers directly grown on Si due to their better tolerance to crystal defects and thermal stability. Here we report optically pumped InP-based InAs QDash microdisk lasers (MDLs) directly grown on on-axis (001) Si. To the best of our knowledge, this is the first demonstration of room-temperature continuous-wave lasing of a QDash MDL on Si in the C band and L band. To the best of our knowledge, the lowest threshold of around 400 µW and highest operation temperature of 323 K have been achieved. An analysis of experimental results shows that the dominant lasing wavelength of MDLs varies with the thickness and diameter of the MDLs. Our demonstration shows potential application of MDLs for multi-channel operation in densely integrated Si-photonics.
Full-field measurement of complex objects illuminated by an ultrashort pulse laser using delay-line sweeping off-axis interferometry
Authors: Yu Wenhui , Li Xiang , Hu Rui , Qu Junle , Liu Liwei
Published: May 2021

Measuring the complex field of ultrashort pulse lasers plays a fundamental role in light wavefront manipulation and nonlinear phenomena investigation; yet, it still constitutes a challenge for both full-field and high-resolution characterization due to the short coherent length. We proposed and implemented an off-axis interference system with a delay-line sweeping technique to overcome the fringe contrast degradation caused by the envelope mismatch between interfering pulses, resulting in an increased effective analysis area. The effectiveness of the proposed method was first demonstrated by measuring a complex field generated by a phase-only spatial light modulator, where a four-pixel binning technique was adopted for both amplitude and phase modulation; then it was used for the measurement of the second harmonic generation signal of a urea crystal sample. The experimental results show that the proposed method is capable of measuring complex fields having fine features within the full field. The proposed technique can be applied for strongly scattering medium refocusing and adaptive optics, where measuring the complex field of ultrashort pulse lasers is essential.
Room temperature atomic frequency comb storage for light
Authors: Main D. , Hird T. M. , Gao S. , Walmsley I. A. , Ledingham P. M.
Published: May 2021

We demonstrate coherent storage and retrieval of pulsed light using the atomic frequency comb protocol in a room temperature alkali vapor. We utilize velocity-selective optical pumping to prepare multiple velocity classes in the

F
=
4

hyperfine ground state of cesium. The frequency spacing of the classes is chosen to coincide with the

F
′

=
4
−

F
′

=
5

hyperfine splitting of the

6
2

P

3

/

2

excited state, resulting in a broadband periodic absorbing structure consisting of two usually Doppler-broadened optical transitions. Weak coherent states of duration

2

n
s

are mapped into this atomic frequency comb with pre-programmed recall times of

8

n
s

and

12

n
s

, with multi-temporal mode storage and recall demonstrated. Utilizing two transitions in the comb leads to an additional interference effect upon rephasing that enhances the recall efficiency.
Large refractive index modulation based on a BDK-doped step-index PMMA optical fiber for highly reflective Bragg grating inscription
Authors: Hu Xuehao , Yue Xiaoyu , Cheng Xin , Gao Shixin , Min Rui , Wang Heng , Qu Hang , Tam Hwa-Yaw
Published: May 2021

We experimentally report high reflectivity on the poly(methyl methacrylate) (PMMA)-based polymer optical fiber Bragg gratings by means of a 266 nm pulsed laser and phase mask technique. In the first recipe, fiber Bragg gratings (FBGs) were manufactured with a single pulse up to 3.7 mJ. After post-annealing, a stable refractive index change up to

4.2

×

10

−
4

was obtained. In the second recipe, FBGs were inscribed by 22 pulses with a lower pulse energy of 1.4 mJ, showing a stable refractive index change of

6.2

×

10

−
4

. Both behaviors may mainly be attributed to the movement of initiating radicals arising from benzyl dimethyl ketal (BDK) under UV irradiation. The high refractive index change in step-index fibers paves the way to tilted FBG manufacturing with large tilt angles potentially for biomedical applications.
Beyond near-infrared lossy mode resonances with fluoride glass optical fiber
Authors: Vitoria I. , Zamarreño C. R. , Ozcariz A. , Imas J. J. , Matias I. R.
Published: May 2021

The objective of this Letter consists of the exploration of the lossy mode resonance (LMR) phenomenon beyond the near-infrared region and specifically in the short wave infrared region (SWIR) and medium wave infrared region (MWIR). The experimental and theoretical results show for the first time, to the best of our knowledge, not only LMRs in these regions, but also the utilization of fluoride glass optical fiber associated with this phenomenon. The fabricated devices consist of a nanometric thin-film of titanium dioxide used as LMR generating material, which probed extraordinary sensitivities to external refractive index (RI) variations. RI sensitivity was studied in the SWIR and MWIR under different conditions, such as the LMR wavelength range or the order of resonance, showing a tremendous potential for the detection of minute concentrations of gaseous or biological compounds in different media.
Real-world outcomes for a complete nationwide cohort of more than 3200 teriflunomide-treated multiple sclerosis patients in The Danish Multiple Sclerosis Registry
Authors: Papp Viktoria , Buron Mathias Due , Siersma Volkert , Rasmussen Peter Vestergaard , Illes Zsolt , Kant Matthias , Hilt Claudia , Mezei Zsolt , Roshanisefat Homayoun , Sejbæk Tobias , Weglewski Arkadiusz , van Wingerden Janneke , Geertsen Svend Sparre , Bramow Stephan , Sellebjerg Finn , Magyari Melinda
Published: May 2021

Objective

Teriflunomide is a once-daily, oral disease-modifying therapy (DMT) for relapsing forms of multiple sclerosis (MS). We studied clinical outcomes in a real-world setting involving a population-based large cohort of unselected patients enrolled in The Danish Multiple Sclerosis Registry (DMSR) who started teriflunomide treatment between 2013–2019.

Methods

This was a complete nationwide population-based cohort study with prospectively enrolled unselected cases. Demographic and disease-specific patient parameters related to treatment history, efficacy outcomes, and discontinuation and switching rates among other clinical variables were assessed at baseline and during follow-up visits.

Results

A total of 3239 patients (65.4% female) started treatment with teriflunomide during the study period, 56% of whom were treatment-naïve. Compared to previously treated patients, treatment-naïve patients were older on average at disease onset, had a shorter disease duration, a lower Expanded Disability Status Scale score at teriflunomide treatment start and more frequently experienced a relapse in the 12 months prior to teriflunomide initiation. In the 3001 patients initiating teriflunomide treatment at least 12 months before the cut-off date, 72.7% were still on treatment one year after treatment start. Discontinuations in the first year were due mainly to adverse events (15.6%). Over the full follow-up period, 47.5% of patients discontinued teriflunomide treatment. Sixty-three percent of the patients treated with teriflunomide for 5 years were relapse-free, while significantly more treatment-naïve versus previously treated patients experienced a relapse during the follow-up (p<0.0001). Furthermore, 85% of the patients with available data were free of disability worsening at the end of follow-up.

Conclusions

Solid efficacy and treatment persistence data consistent with other real-world studies were obtained over the treatment period. Treatment outcomes in this real-world scenario of the population-based cohort support previous findings that teriflunomide is an effective and generally well-tolerated DMT for relapsing MS patients with mild to moderate disease activity.
Seasonality, molecular epidemiology, and virulence of Respiratory Syncytial Virus (RSV): A perspective into the Brazilian Influenza Surveillance Program
Authors: Vianna Lucas A. , Siqueira Marilda M. , Volpini Lays P. B. , Louro Iuri D. , Resende Paola C.
Published: May 2021

Background

Respiratory Syncytial Virus (RSV) is the main cause of pediatric morbidity and mortality. The complex evolution of RSV creates a need for worldwide surveillance, which may assist in the understanding of multiple viral aspects.

Objectives

This study aimed to investigate RSV features under the Brazilian Influenza Surveillance Program, evaluating the role of viral load and genetic diversity in disease severity and the influence of climatic factors in viral seasonality.

Methodology

We have investigated the prevalence of RSV in children up to 3 years of age with severe acute respiratory infection (SARI) in the state of Espirito Santo (ES), Brazil, from 2016 to 2018. RT-qPCR allowed for viral detection and viral load quantification, to evaluate association with clinical features and mapping of local viral seasonality. Gene G sequencing and phylogenetic reconstruction demonstrated local genetic diversity.

Results

Of 632 evaluated cases, 56% were caused by RSV, with both subtypes A and B co-circulating throughout the years. A discrete inverse association between average temperature and viral circulation was observed. No correlation between viral load and disease severity was observed, but children infected with RSV-A presented a higher clinical severity score (CSS), stayed longer in the hospital, and required intensive care, and ventilatory support more frequently than those infected by RSV-B. Regarding RSV diversity, some local genetic groups were observed within the main genotypes circulation RSV-A ON1 and RSV-B BA, with strains showing modifications in the G gene amino acid chain.

Conclusion

Local RSV studies using the Brazilian Influenza Surveillance Program are relevant as they can bring useful information to the global RSV surveillance. Understanding seasonality, virulence, and genetic diversity can aid in the development and suitability of antiviral drugs, vaccines, and assist in the administration of prophylactic strategies.
Pool testing on random and natural clusters of individuals: Optimisation of SARS-CoV-2 surveillance in the presence of low viral load samples
Authors: Baccini Michela , Rocco Emilia , Paganini Irene , Mattei Alessandra , Sani Cristina , Vannucci Giulia , Bisanzi Simonetta , Burroni Elena , Peluso Marco , Munnia Armelle , Cellai Filippo , Pompeo Giampaolo , Micio Laura , Viti Jessica , Mealli Fabrizia , Carozzi Francesca Maria
Published: May 2021

Facing the SARS-CoV-2 epidemic requires intensive testing on the population to early identify and isolate infected subjects. During the first emergency phase of the epidemic, RT-qPCR on nasopharyngeal (NP) swabs, which is the most reliable technique to detect ongoing infections, exhibited limitations due to availability of reagents and budget constraints. This stressed the need to develop screening procedures that require fewer resources and are suitable to be extended to larger portions of the population. RT-qPCR on pooled samples from individual NP swabs seems to be a promising technique to improve surveillance. We performed preliminary experimental analyses aimed to investigate the performance of pool testing on samples with low viral load and we evaluated through Monte Carlo (MC) simulations alternative screening protocols based on sample pooling, tailored to contexts characterized by different infection prevalence. We focused on the role of pool size and the opportunity to develop strategies that take advantage of natural clustering structures in the population, e.g. families, school classes, hospital rooms. Despite the use of a limited number of specimens, our results suggest that, while high viral load samples seem to be detectable even in a pool with 29 negative samples, positive specimens with low viral load may be masked by the negative samples, unless smaller pools are used. The results of MC simulations confirm that pool testing is useful in contexts where the infection prevalence is low. The gain of pool testing in saving resources can be very high, and can be optimized by selecting appropriate group sizes. Exploiting natural groups makes the definition of larger pools convenient and potentially overcomes the issue of low viral load samples by increasing the probability of identifying more than one positive in the same pool.
Prolonged ex-vivo normothermic kidney perfusion: The impact of perfusate composition
Authors: Pool Merel B. F. , Hamelink Tim L. , van Goor Harry , van den Heuvel Marius C. , Leuvenink Henri G. D. , Moers Cyril
Published: May 2021

Normothermic machine perfusion (NMP) of donor kidneys provides the opportunity for improved graft preservation and objective pre-transplant ex-vivo organ assessment. Currently, a multitude of perfusion solutions exist for renal NMP. This study aimed to evaluate four different perfusion solutions side-by-side and determine the influence of different perfusate compositions on measured renal perfusion parameters. Porcine kidneys and blood were obtained from a slaughterhouse. Kidneys underwent NMP at 37°C for 7 hours, with 4 different perfusion solutions (n = 5 per group). Group 1 consisted of red blood cells (RBCs) and a perfusion solution based on Williams’ Medium E. Group 2 consisted of RBCs, albumin and a balanced electrolyte composition. Group 3 contained RBCs and a medium based on a British clinical NMP solution. Group 4 contained RBCs and a medium used in 24-hour perfusion experiments. NMP flow patterns for solutions 1 and 2 were similar, solutions 3 and 4 showed lower but more stable flow rates. Thiobarbituric acid reactive substances were significantly higher in solution 1 and 4 compared to the other groups. Levels of injury marker N-acetyl-β-D glucosaminidase were significantly lower in solution 2 in comparison with solution 3 and 4. This study illustrates that the perfusate composition during NMP significantly impacts the measured perfusion and injury parameters and thus affects the interpretation of potential viability markers. Further research is required to investigate the individual influences of principal perfusate components to determine the most optimal conditions during NMP and eventually develop universal organ assessment criteria.
Physician skin cancer screening among U.S. military veterans: Results from the National Health Interview Survey
Authors: Coups Elliot J. , Xu Baichen , Heckman Carolyn J. , Manne Sharon L. , Stapleton Jerod L.
Published: May 2021

Introduction

Although military veterans are at increased risk for skin cancer, little is known about the extent to which they have been screened for skin cancer. The study objective was to examine the prevalence and correlates of physician skin cancer screening among U.S. military veterans.

Methods

Data were drawn from the National Health Interview Survey. The study sample consisted of 2,826 individuals who reported being military veterans. Receipt of a physician skin examination was measured using a single question that asked participants whether they had ever had all of their skin from head to toe checked for cancer by a dermatologist or some other kind of doctor.

Results

Less than a third (30.88%) of participants reported ever having a physician skin examination. Factors positively associated with receipt of a physician skin examination in a multivariable logistic regression analysis included: older age, greater educational level, non-Hispanic white race/ethnicity, having TRICARE (military) health insurance, greater skin sensitivity to the sun, and engagement in more sun protection behaviors.

Conclusions

The majority of military veterans have never been screened for skin cancer by a physician. Screening rates were higher among individuals with one or more skin cancer risk factors. Future research is warranted to test targeted skin cancer screening interventions for this at risk and understudied population.
Effects of different models of sucrose intake on the oxidative status of the uterus and ovary of rats
Authors: Sadowska Joanna , Dudzińska Wioleta , Dziaduch Izabela
Published: May 2021

The aim of the study was to assess the effect of different models of sucrose intake on carbohydrate-lipid metabolism and changes in oxidant balance in the ovaries and uterus of rats. Animals were divided into three groups: I—basic feed, II—feed contains 8% of sucrose, III—alternately every second week the basic feed and modified feed contains 16% of sucrose. The diet containing 8% of sucrose was found to result in an increased activity of antioxidant enzymes in the blood, with unchanged malonylodialdehyde concentration. Variable sucrose administration pattern intensified oxidative stress in the blood and led to disturbed redox equilibrium in the rat uterus, even at a comparable long-term sucrose uptake as in the group II. This was manifested as a reduced superoxide dismutase activity (in the blood and uterus) and a higher malonylodialdehyde concentration (in the uterus). The changes observed could have been a result of metabolic disorders (higher amount of visceral fat, higher glucose concentration, higher index of homeostasis model assessment of insulin resistance, and reduced HDL-cholesterol concentration) and endocrine disorders (higher oestrogen concentrations). Changes in the antioxidant status in the rats kept on the alternating diet, may underpin the failure of fertilised egg implantation in the uterine tissue and pregnancy completion.
Testing of four-sample pools offers resource optimization without compromising diagnostic performance of real time reverse transcriptase-PCR assay for COVID-19
Authors: Singh Anirudh K. , Nema Ram Kumar , Joshi Ankur , Shankar Prem , Gupta Sudheer , Yadav Ashvini Kumar , Nema Shashwati , Mathew Bijina J. , Shrivas Arti , Patankar Chitra , Raghuwanshi Arun , Pandey Ritu , Tripathi Ranu , Ansari Kudsia , Singh Kuldeep , Yadav Jogender , Biswas Debasis , Singh Sarman
Published: May 2021

Quick identification and isolation of SARS-CoV-2 infected individuals is central to managing the COVID-19 pandemic. Real time reverse transcriptase PCR (rRT-PCR) is the gold standard for COVID-19 diagnosis. However, this resource-intensive and relatively lengthy technique is not ideally suited for mass testing. While pooled testing offers substantial savings in cost and time, the size of the optimum pool that offers complete concordance with results of individualized testing remains elusive. To determine the optimum pool size, we first evaluated the utility of pool testing using simulated 5-sample pools with varying proportions of positive and negative samples. We observed that 5-sample pool testing resulted in false negativity rate of 5% when the pools contained one positive sample. We then examined the diagnostic performance of 4-sample pools in the operational setting of a diagnostic laboratory using 500 consecutive samples in 125 pools. With background prevalence of 2.4%, this 4-sample pool testing showed 100% concordance with individualized testing and resulted in 66% and 59% reduction in resource and turnaround time, respectively. Since the negative predictive value of a diagnostic test varies inversely with prevalence, we re-tested the 4-sample pooling strategy using a fresh batch of 500 samples in 125 pools when the prevalence rose to 12.7% and recorded 100% concordance and reduction in cost and turnaround time by 36% and 30%, respectively. These observations led us to conclude that 4-sample pool testing offers the optimal blend of resource optimization and diagnostic performance across difference disease prevalence settings.