bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication of periodic bowtie structure on vanadium dioxide by nanosphere lithography for smart window applications
Authors: Lu Ying-Chou , Lai Yi-Chen , Li Jia-Han , Hsueh Chun-Hway
Published: December 2022

Nanophotonics has been extensively researched in the past decades owing to the rapid development of the precision nanofabrication techniques, such as focused-ion beam milling and electron-beam lithography. However, it was limited by some disadvantages, such as high cost and low productivity. Therefore, a facile and economics method, nanosphere lithography (NSL) [1], for fabricating multiple nanostructures has been reported. Polystyrene nanospheres, with diameters of several hundred nanometers, were aligned into a monolayer. By using close-packed polystyrene nanospheres array as a mask, periodic metal bowties can be fabricated after metal evaporation and nanospheres lift-off.
Fiber Optic SPR based Dopamine Sensor utilizing GNP/SnO2 Nanocomposite Sup-ported Molecular Imprinting
Authors: Sharma Sonika , Gupta Banshi D.
Published: December 2022

Dopamine (DA) belongs to the catecholamine family of neurotransmitters and is very important for humans. It is produced in adrenal glands and several areas of the brain. Dopamine is formed by decarboxylation of DOPA and is a precursor of two other neurotransmitters adrenaline and noradrenalin. Dopamine is the most abundant of the catecholamine, hence affects many aspects of brain functionality such as movement, emotional response and ability to experience pain and pleasure. Dopamine also affects the cardiovascular and renal systems. Excessive secretion of DA (e.g., due to Huntington’s disease) is associated with failure in energy metabolism and causes untimely death. Differently low levels of dopamine in the central nervous system causes several neurological diseases, for example schizophrenia, Parkinson’s disease. Therefore, it is important to detect dopamine level efficiently in human body [1].
Value-Added ABC Semiconductor Material for Various Applications
Authors: Nishibe Tohru , Ito Kengo
Published: December 2022

We would like to propose a novel semiconductor material that can show both plasmonic and electric properties. Moreover, using smectite clay, whole structure of this material can be designed so that it is easily printed in any kinds of solvents. As is shown in Fig.1, ABC semiconductor means the desirable composite of Ag nanoplate, boron, and clay[1]. Plasmon resonance is controlled around Ag plate surface by adjusting its size and the plasmon energy can be transferred to boron semiconductor and excite it[2]. ABC semiconductor will pave the way for various applications, such as energy harvesting cells with storage effect, functional films that reflect or absorb only the light with specific wavelength up to infrared region, non-contact antibacterial coating by usage of strong electric fields induced by plasmon resonance, as well as SERS. In this paper, a photo-voltaic cell as one of applications has been studied.
Theoretical Considerations on Plasmonic Enhancement of THz Electric Field in Parallel-Plate Waveguides Coupled to V-groove Tapered Waveguides
Authors: Kurihara Kazuyoshi , Kusama Kiwamu , Kuwashima Fumiyoshi , Morikawa Osamu , Yamamoto Kohji , Kitahara Hideaki , Tani Masahiko
Published: December 2022

Plasmonic waveguides of tapered structures such as metallic V-groove and cone have the capability to confine terahertz (THz) electromagnetic waves into an area smaller than the diffraction limit. We experimentally demonstrated that parallel-plate waveguides (PPWGs) coupled to V-groove tapered waveguides are very simple and useful structures to increase the sensitivity of electrooptic sampling technique due to the enhancement of electric field of linearly polarized THz waves1). However, a mechanism of the enhancement is not enough to provide theoretically because plasmonic effects are frequently ignored under the condition of perfect conductor approximation for metallic materials in the THz region. This paper provides a theoretical method to calculate enhancement factors of electric field for THz waves in PPWGs coupled to V-groove waveguides as shown in Fig.1 by considering the voltage reflection coefficient of two plasmonic modes in parallel-plate and V-groove waveguides.
Improvement on pattern matching method for hand-waving finger vein authentication
Authors: Suzuki Hiroyuki , Hayashi Hiroki , Obi Takashi , Ohyama Nagaaki , Komuro Takashi
Published: December 2022

Recently, the application field of biometric authentication is expanding from small-scale service to wide-scale one such as big event venue, theme park, and so on. In these situations, high-speed calculation and smooth operation are required because of a large number of users. In order to apply finger vein authentication to above services, a walkthrough type finger vein authentication is effective. In our previous study, a hand waving finger vein authentication system was proposed [1]. However, it is hard for this system to achieve high-speed calculation and highly accurate authentication simultaneously. In this study, we propose an improved pattern matching method that make it possible to accelerate the calculation of the finger vein authentication by applying Scale-Invariant Feature Transform (SIFT).
Light Field Microscopy Combined with Super-resolution Techniques
Authors: Usuki Shin , Tani Yoshitake , Miura Kenjiro T.
Published: December 2022

This study introduces a light field microscopy (LFM) in which a microlens array is employed for spatial and angular sampling of light from an object through an objective lens in a wide-field optical microscopy. The LFM has expanded depth of field and digital refocusing ability for 3D measurement. However, it has a critical drawback that spatial resolution is limited by spatial sampling determined by diameter of each microlens. Typically each microlens have several sub-millimeter diameter, hence the cutoff frequency in the diffraction limited imaging system spatial exceeds spatial sampling frequency in the LFM images. As one of the solutions for this problem, resolution improvement based on sub-pixel shift multi-image processing was proposed. Then the experimental apparatus to verify the proposed method was developed. The resulting image (see Figure. 1) exhibited higher spatial resolution than that of a sub-aperture image obtained by a typical light field microscopy. Furthermore, a different approach towards the super-resolution of the LFM, which employs Fourier Ptychography a kind of computational imaging technique, will be introduced.
Problems with using optical flow algorithms for volumetric sources
Authors: Hagen Nathan
Published: December 2022

Optical flow algorithms were originally developed for estimating the motion of opaque objects. In the case of semi-transparent fluids, the object is a volumetric distribution that exhibits motion in three dimensions. In principle, adapting optical flow algorithms to 3D flow seems simple: we still have a 2D image to work with, representing a projection through a 3D volumetric object. And now we need only consider the velocity estimate as being an average through the object along the line of sight, instead of the velocity at a single point. Unfortunately, however, this simple step creates flaws in the algorithm that are easily overlooked.
Dynamically swarming gold nanoparticles formed by laser trapping at glass/solution interface
Authors: Kudo Tetsuhiro , Yang Shang-Jan , Masuhara Hiroshi
Published: December 2022

Laser trapping has been utilized as tweezers to three-dimensionally trap nanoscale objects (such as dielectric nanoparticles, metallic nanoparticles, semiconductor quantum dots, proteins, molecular clusters, etc.) and has provided significant impacts in nanoscience and nanotechnology.
Ag-nanoislands Mediated TiO2 Multilayer Thin Films towards Perfect Absorber
Authors: Dewasi Avijit , Mitra Anirban
Published: December 2022

Under illumination, metallic nano-particles show a characteristic absorption peak originated due to localized surface plasmon resonance (LSPR) [1].
Asymmetric Fabry-Perot cavity based perfect absorber for infrared spectroscopic devices
Authors: Doan Anh Tung , Dao Thang Duy , Ishii Satoshi , Nagao Tadaaki
Published: December 2022

Artificial subwavelength structures such as plasmonic perfect absorbers, metallic gratings and photonic crystals have been proposed to tailor the spectral absorption for spectroscopic devices.
Fluorescent Imaging of Live Hippocampal Neurons with Platinum Nanoclusters
Authors: Fujieda Minami , Masui Kyoko , Hosokawa Chie , Ishitobi Hidekazu , Inouye Yasushi
Published: December 2022

Fluorescent imaging is a powerful technique to reveal how target cells or biomolecules work in biological tissues and cells. So far, organic dyes, fluorescent proteins, and quantum dots have been developed and widely used as a fluorescent probe.
All-ceramic solar-driven water purifier based on anodized aluminum oxide and plasmonic titanium nitride
Authors: Kaur Manpreet , Ishii Satoshi , Shinde Satish Laxman , Nagao Tadaaki
Published: December 2022

Titanium nitride (TiN) nanoparticles (NPs) act as excellent solar-heat nano-generators due to their broadband plasmonic resonances together with their chemical stability. So far, TiN NPs have been studied without loaded onto any host or support materials for solar water distillation system, which make them difficult to re-use in practical applications [1].
Protruding Aerial DFD Display in Combination of a Flat-Panel Display and AIRR
Authors: Terashima Yoshiki , Suyama Shiro , Yamamoto Hirotsugu
Published: December 2022

The aerial display has been gaining attention as digital signage, amusement and next-generation car interface. The aerial image is observed as if it is floating in the air without using special 3D glasses. Aerial imaging by retro-reflection (AIRR) [1] is one of the aerial imaging techniques. One of the features of aerial image is it is translucent. Therefore, it is possible to observe the aerial image while observing the object back of the aerial image.
Mid infrared plasmon metasurfaces for sensing applications
Authors: Nishijima Yoshiaki
Published: December 2022

Plasmon perfect absorbers (PPAs) are plasmonic metasurface structures which consist of the thick metal film, insulator layer, and plasmonic nanostructures.
Construction of visible responsive broadband absorber utilizing strong coupling between plasmon and nanocavity modes and its application to light energy conversions
Authors: Ueno Kosei , Shi Xu , Sun Quan , Oshikiri Tomoya , Sasaki Keiji , Misawa Hiroaki
Published: December 2022

Nanoparticles colloidal solutions of metals such as gold (Au) and silver (Ag) show very intense color due to localized surface plasmon resonances (LSPRs). LSPRs which are collective oscillations of conduction electrons give rise to the enhancement of electromagnetic field in the vicinity of nanoparticles and are expected as a light harvesting optical antenna for light energy conversion devices based on their spectrum tunability. We have successfully developed the plasmon-induced energy conversions such as water splitting and ammonia synthesis systems as well as solid-state plasmonic solar cells based on the principle of plasmon-induced hot electron transfer from gold nanoparticles (Au-NPs) to the semiconductor electrode.1−5
Extended Abstract of the Japan Society of Applied Physics
Authors: Kumar Samir , Doi Yusuke , Namura Kyoko , Suzuki Motofumi
Published: December 2022

In the past few decades, Raman scattering has gained attention as a spectroscopic technique for the study of chemical and biological sensing, as it is a label-free non-invasive method.[1] However, the main drawback of Raman spectroscopy is the intrinsically low signal intensity, which leads to unsuitably high detection limits. Hence, the exploitation of plasmonics for enhancing Raman signal has become an important factor for the routine application of this technique. Silicon wafers and glass slides are two of the most common substrates used for the growth of SERS active layers.[2] However, these substrates are rigid and brittle, and hence, these static substrates severely limit the application of plasmonic nanostructures. Flexible substrates have an advantage over the conventional rigid substrates because of their ability to conform to the underlying object.[3] They can be wrapped onto curved surfaces and can be easily cut into different shapes and sizes for applications which demand non-planar, flexible or conformal surfaces.[4]
Beyond the diffraction limit by Light-Sheet Microscopy
Authors: Chen Bi-Chang
Published: December 2022

By combination with the advantage of localization microscopy and light-sheet microscopy, one could get super-resolved cellular imaging in 3D across large field of view. The localization process is determined by on-off switching of spontaneously blinking fluorophore based on intramolecular spirocyclization reaction without intense laser irradiation or additives8. With high-density labeled spontaneous blinking fluorophore and wide-field detection of light-sheet microscopy, these allow us to construct 3D super-resolution multicellular imaging at high speed (~minutes) by light-sheet single-molecule localization microscopy. Extended from cultured cells, an intact tissue imaging with high spatial resolution is technically challenging and required for the understanding of whole brain connectome. Due to the sample-induced aberration, the diffraction-limit resolution and beyond is hard to achieve at the tissue level.
Unveiling Defect-Induced Raman Mode of Transition Metal Dichalcogenides Monolayer Using Tip-Enhanced Resonance Raman Spectroscopy
Authors: Lee Chanwoo , Lee Seung Mi , Jeong Mun Seok
Published: December 2022

In this presentation, analysis of 2D nanomaterials with Tip enhanced Raman scattering (TERS) will be provided. TERS is a unique tool for investigating Raman scattering mapping with nanometer spatial resolution beyond optical diffraction limit. Using representative tips fabricated under the optimal etching condition, Our lab. demonstrate the TERS experiment of tungsten disulfide (WS2) monolayer grown by a chemical vapor deposition method with a spatial resolution of ~40 nm. Monolayer WS2 has emerged as an active material for optoelectronic devices due to its quantum yield of photoluminescence. Despite the enormous research about physical characteristics of monolayer WS2, the defect-related Raman scattering has been rarely studied. In this work, we report the correlation of topography and Raman scattering in monolayer WS2 by using TERS and reveal defect-related Raman modes denoted as D and D′ modes. We found that the sulfur vacancies introduce not only the red-shifted A1g mode but also the D and D′ modes by the density functional theory calculations. The observed defect-related Raman modes can be utilized to evaluate the quality of monolayer WS2 and will be helpful to improve the performance of WS2 optoelectronic devices.
Ultrastrong Plasmon-Exciton Coupling between Ag Nanoparticles and Conjugated Polymers
Authors: Petoukhoff Christopher E. , Dani Keshav M. , O’Carroll Deirdre M.
Published: December 2022

Strong light-matter interactions involving organic semiconductors are important for a number of technical applications, including low-threshold lasing [1] and room-temperature Bose-Einstein condensates [2]. Coupling between excitons in organic semiconductors and surface plasmons results in the formation of plasmon-exciton hybridized modes, which are observed as energetic splitting in the normal modes of the coupled system (i.e., Rabi splitting) [3]. Typically, excitons with narrow resonances, such as those found in. J-aggregates, are used to achieve strong coupling, where the rate of energy exchange between excitons and plasmons in the hybrid system exceeds the decay rates of the plasmons and excitons in the isolated systems. However, for many applications, including plasmon-enhanced photovoltaics, light- emitting diodes, and spasers, coupling between plasmons and excitons within conjugated polymers is of great interest [4-6].
Characterization of octagonal silicon pillar for meta-atom of dielectric metasurface
Authors: Iwami Kentaro , Ogawa Chikara
Published: December 2022

Dielectric metasurfaces are promising optical components due to lossless nature and broad functionality including lenses, polarizers, waveplates, routers, holography, and so on. These metasurfaces consist of meta-atoms made of transparent and high index materials at the designed wavelength. Silicon (n = 4 ~ 3.5 at 700 nm ~ 1 μm) is very promising material at the near-infrared range[1], although it has absorption in the visible region. In addition, as the band gap increases, dielectric constant decreases so it requires much higher aspect ratio in the visible range, which makes fabrication difficult. Meta-atoms consists of a high-aspect ratio pillars, posts or holes with circular, rectangular, or polygonal two-dimensional shape. Since subwavelength feature size is required, electron beam lithography (EBL) is essential, including production of mask reticle for stepper or nanoimprint molds. However, complicated and massively-parallel pattern of metafurfaces for enough functionality makes EBL difficult through both increase of exposure data file size and lengthening of exposure time.
Hexa-petal Antenna for Complex Spatial Light Modulation
Authors: Lee Jonghyun , Park Sungjae , Park Shin-Woong , Kim Hwi
Published: December 2022

Digital holography is a technology that can recognize for us hologram of three-dimensional (3D) object. If we observe a noise-free reconstructed image, it is required to modulate simultaneously amplitude and phase for single pixel of computer generated hologram (CGH). However, conventional design technique of holographic display has an issue that occurs low quality and significant noise because it can modulate only one element such as amplitude-only or phase-only. Recently, for solving this issue, meta-surface technology has been researched and developed, which is able to control complex spatial light modulation by structural specification [1-3]. In this study, we propose a new pixel design that is able to modulate simultaneously amplitude and phase. Also, we analyzed characteristics of complex modulation of unit-pixel using wave optical simulations. Based on this results, we verified increasing a quality of reconstructed image for low noise hologram.
Terahertz Pulses with High-Field Unipolar Precursors
Authors: Bakunov M. I. , Tsarev M. V.
Published: December 2022

Strong electric and magnetic fields in the terahertz frequency range are required for many applications, including particle acceleration, molecular orientation, and terahertz streaking techniques. The strongest fields are currently generated by optical rectification of ultrashort laser pulses in nonlinear crystals. Multiphoton absorption is considered as one of the main factors that limits the optical pump intensity. It leads to a depletion of the pump pulse and photogeneration of free carriers that absorb terahertz radiation.
Bulk photovoltaic effect in WSe2/Black Phosphorus interfaces
Authors: Ideue Toshiya , Akamatsu Takatoshi , Zhou Ling , Dong Yu , Kitamura Sota , Yoshii Mao , Yang Dongyang , Onga Masaru , Nakagawa Yuji , Watanabe Kenji , Taniguchi Takashi , Laurienzo Joseph , Huang Junwei , Ye Ziliang , Morimoto Takahiro , Yuan Hongtao , Iwasa Yoshihiro
Published: December 2022

Interfaces of two dimensional van der Waals crystals are unique material platforms in which we can explore the emergent physical properties and functionalities by selecting the appropriate material combinations and by designing the symmetry of the interface.
Dominating Interlayer Resonant Energy Transfer in Type-II Atomically Thin Semiconductor Heterostructures
Authors: Karmakar Arka , Al-Mahboob Abdullah , Petoukhoff Christopher E. , Kravchyna Oksana , Chan Nicholas S. , Taniguchi Takashi , Watanabe Kenji , Dani Keshav M.
Published: December 2022

Newly emerging transition metal dichalcogenide (TMD) materials have gained significant interest in last decade due to their unique quantum properties in monolayer regime.
Optical properties of lateral heteromonolayer WSe2–MoSe2
Authors: Shimasaki Masafumi , Nishihara Taishi , Matsuda Kazunari , Endo Takahiko , Miyata Yasumitsu , Miyauchi Yuhei
Published: December 2022

Unlike most of bulk semiconductors, excitons in mono-layer transition metal dichalcogenides dominate their optical properties even at room temperature due to their large binding energies [1–5].
Tailoring photoluminescence with metasurfaces
Authors: Murai Shunsuke
Published: December 2022

Recently, periodic arrays of nanoparticles have been widely utilized as metasurfaces to control light at the interface.
Thermal Crosstalk Evaluation of Densely Packed 1.1 μm-band VCSEL Array for Multi-core Fiber Transmission
Authors: Dong Liang , Gu Xiaodong , Koyama Fumio
Published: December 2022

Edge data centers (EDCs) have been attracting much attention due to the rapid growth of big data, the Internet of Things (IoT) and 5G mobile networking.
Record Low Power Consumption 1060nm Single-mode Intracavity Metal Aperture VCSEL with Transverse Resonance
Authors: Ibrahim Hameeda R , Hassan Ahmed M. A. , Gu Xiodong , Shinada Satoshi , Ahmed Moustafa , Koyama Fumio
Published: December 2022

Vertical-cavity surface emitting lasers (VCSELs) is a key component for datacenter networks due to their advantages such as low cost and low power consumption [1-2].
Plasmonic Nanolaser by Silver Nanowire Embedded in CsPbBr3 Quantum Dots
Authors: Xing Di , Lin Cheng-Chieh , Won Phillip , Xiang Rong , Chen Tzu-Pei , Kamal A. Syazwan A. , Lee Yang-Chun , Ho Ya-Lun , Maruyama Shigeo , Ko Seung Hwan , Chen Chun-Wei , Delaunay Jean-Jacques
Published: December 2022

Plasmonic nanolasers provide a valuable opportunity for expanding sub-wavelength applications in the fields of biosensing,[1] nonlinear frequency generation,[2] and optical switching.[3]
Direct print of magnetic particles by optical vortex - laser induced forward transfer
Authors: Kaneko Akihiro , Iwata Muneaki , Kawaguchi Haruki , Umesato Kei , Omatsu Takashige
Published: December 2022

Optical vortex with a spiral wavefront carries an annular spatial form with a central dark core and an orbital angular momentum (OAM) associated with its helical wavefront.
Terahertz Magnetospectroscopy of Gadolinium Gallium Garnet in Fields up to 25 T
Authors: Bao J. , Peraca N. Marquez , Tay F. , Kritzell T. E. , Li X. , Noe G. T. , Katayama I. , Takeda J. , Nojiri H. , Yamahara H. , Tabata H. , Baydin A. , Kono J.
Published: December 2022

Terahertz (THz) spectroscopy of solids in high magnetic fields can often provide new insight into the microscopic physics behind complex many-body behaviors [1].
Concise method for high-precision vibration recovery of Φ-OTDR based on the GF-FastICA algorithm
Authors: Huang Yi , Li Ying , Chen Xiaofeng , Dai Jingyi , Chen Lin , Hu Chengyong , Deng Chuanlu , Zhang Qi , Pang Fufei , Zhang Xiaobei , Wang Tingyun
Published: December 2022

To efficiently restore the vibration signals of a phase-sensitive optical time domain reflectometer (Φ-OTDR), the GF-FastICA joint algorithm is proposed, which combines guided filtering with fast independent component analysis (FastICA). The marked region of vibration is precisely located by guided filtering. FastICA deals with the optimal phase mixing matrix of the marked region to separate the vibration signals from the noise-containing phase signals. The experimental results show that the GF-FastICA achieves a correlation coefficient of 0.998 for 5-Hz vibration signal recovery from a 14.3-km sensing fiber, verifying the potency of the algorithm. Compared with the traditional method and FastICA only, GF-FastICA improves the root mean square error (RMSE) metric by an order of magnitude, which is approaching an experience value of 10−3.
Great increase of the tensile strength in the lamellar PI-coated FBG sensors
Authors: Li Xiaojin , Shen Zhenkun , Zheng Min , Hou Dan , Wen Qiao
Published: December 2022

The pristine fiber has a tensile strength of 5 GPa while it can be reduced to 0.4 MPa after writing FBG by using the UV laser based phase mask technology. Herein, we report four lamellar polyimide (PI)-coated FBG sensors with great increase of the tensile strength. Our results show that the average tensile strength of the lamellar PI-coated FBG sensors is 2.8 times higher than the value of the uncoated FBG sensors. More importantly, compared with the uncoated FBG sensors, the lamellar PI-coated film can effectively protect the uncoated FBG sensors from a fracture at the grating area. In addition, the lamellar PI-coated FBG sensors also possess good force sensing capabilities, which indicate that the lamellar PI-coated FBG sensors can be considered as a candidate for force sensing applications.
Fast shaping control of x ray beams using a closed-loop adaptive bimorph deformable mirror
Authors: Alcock Simon G. , Nistea Ioana-Theodora , Badami Vivek G. , Signorato Riccardo , Fusco Matteo , Hu Lingfei , Wang Hongchang , Sawhney Kawal
Published: December 2022

High-speed adaptive correction of optics, based on real-time metrology
feedback, has benefitted numerous scientific communities for several
decades. However, it remains a major technological challenge to extend
this concept into the hard x ray regime due to the necessity for
active mirrors with single-digit nanometer height errors relative to a
range of aspheric forms. We have developed a high-resolution,
real-time, closed-loop “adaptive” optical system for
synchrotron and x ray free electron laser (XFEL) applications. After
calibration of the wavefront using x ray speckle scanning, the
wavefront diagnostic was removed from the x ray beam path.
Non-invasive control of the size and shape of the
reflected x ray beam was then demonstrated by driving a
piezoelectric deformable bimorph mirror at

∼

1

H
z

. Continuous feedback was provided by
a 20 kHz direct measurement of the optical surface with
picometer sensitivity using an array of interferometric sensors. This
enabled a non-specialist operator to reproduce a series of pre-defined
x ray wavefronts, including focused or non-Gaussian profiles, such as
flattop intensity or multiple split peaks with controllable separation
and relative amplitude. Such changes can be applied in any order and
in rapid succession without the need for invasive wavefront diagnostic
sensors that block the x ray beam for scientific usage. These
innovations have the potential to profoundly change how x ray focusing
elements are utilized at synchrotron radiation and XFEL sources and
provide unprecedented dynamic control of photon beams to aid
scientific discoveries in a wide range of disciplines.
Why is leptospirosis hard to avoid for the impoverished? Deconstructing leptospirosis transmission risk and the drivers of knowledge, attitudes, and practices in a disadvantaged community in Salvador, Brazil
Authors: Palma Fabiana Almerinda G. , Costa Federico , Lustosa Ricardo , Mogaji Hammed O. , de Oliveira Daiana Santos , Souza Fábio Neves , Reis Mitermayer G. , Ko Albert I. , Begon Michael , Khalil Hussein
Published: December 2022

Several studies have identified socioeconomic and environmental risk factors for infectious disease, but the relationship between these and knowledge, attitudes, and practices (KAP), and more importantly their web of effects on individual infection risk, have not previously been evaluated. We conducted a cross-sectional KAP survey in an urban disadvantaged community in Salvador, Brazil, leveraging on simultaneously collected fine-scale environmental and epidemiological data on leptospirosis transmission. Residents’ knowledge influenced their attitudes which influenced their practices. However, different KAP variables were driven by different socioeconomic and environmental factors; and while improved KAP variables reduced risk, there were additional effects of socioeconomic and environmental factors on risk. For example, males and those of lower socioeconomic status were at greater risk, but once we controlled for KAP, male gender and lower socioeconomic status themselves were not direct drivers of seropositivity. Employment was linked to better knowledge and a less contaminated environment, and hence lower risk, but being employed was independently associated with a higher, not lower risk of leptospirosis transmission, suggesting travel to work as a high risk activity. Our results show how such complex webs of influence can be disentangled. They indicate that public health messaging and interventions should take into account this complexity and prioritize factors that limit exposure and support appropriate prevention practices.
Genomics-informed outbreak investigations of SARS-CoV-2 using civet
Authors: O’Toole Áine , Hill Verity , Jackson Ben , Dewar Rebecca , Sahadeo Nikita , Colquhoun Rachel , Rooke Stefan , McCrone J. T. , Duggan Kate , McHugh Martin P. , Nicholls Samuel M. , Poplawski Radoslaw ,   The COVID-19 Genomics UK (COG-UK) Consortium,   COVID-19 Impact Project (Trinidad & Tobago Group), Aanensen David , Holden Matt , Connor Tom , Loman Nick , Goodfellow Ian , Carrington Christine V. F. , Templeton Kate , Rambaut Andrew
Published: December 2022

The scale of data produced during the SARS-CoV-2 pandemic has been unprecedented, with more than 13 million sequences shared publicly at the time of writing. This wealth of sequence data provides important context for interpreting local outbreaks. However, placing sequences of interest into national and international context is difficult given the size of the global dataset. Often outbreak investigations and genomic surveillance efforts require running similar analyses again and again on the latest dataset and producing reports. We developed civet (cluster investigation and virus epidemiology tool) to aid these routine analyses and facilitate virus outbreak investigation and surveillance. Civet can place sequences of interest in the local context of background diversity, resolving the query into different ’catchments’ and presenting the phylogenetic results alongside metadata in an interactive, distributable report. Civet can be used on a fine scale for clinical outbreak investigation, for local surveillance and cluster discovery, and to routinely summarise the virus diversity circulating on a national level. Civet reports have helped researchers and public health bodies feedback genomic information in the appropriate context within a timeframe that is useful for public health.
Mortality among healthcare workers in Indonesia during 18 months of COVID-19
Authors: Ekawati Lenny L. , Arif Ahmad , Hidayana Irma , Nurhasim Ahmad , Munziri M. Zakiyuddin , Lestari Karina D. , Tan Amanda , Ferdiansyah Firdaus , Nashiruddin Fikry , Adnani Qorinah E. S. , Malik Halik , Maharani Tri , Riza Andy , Pasaribu Monalisa , Abidin Khairul , Andrianto Adhi A. , Nursalam Nursalam , Suhardiningsih A. V. Sri , Jubaedah Ade , Widodo N. S. , Surendra Henry , Sudoyo Herawati , Smith Adrian D. , Kreager Philip , Baird J. Kevin , Elyazar Iqbal R. F.
Published: December 2022

The impact of SARS-CoV-2 infections upon Indonesian health care workers (HCWs) is unknown due to the lack of systematic collection and analysis of mortality data specific to HCWs in this setting. This report details the results of a systematic compilation, abstraction and analysis of HCW fatalities in Indonesia during the first 18 months of COVID-19. HCW who passed away between March 2020 and July 2021 were identified usingPusara Digital, a community-based digital cemetery database dedicated to HCW. We calculated the mortality rates and death risk ratio of HCWs versus the general population. The analysis indicates that at least 1,545 HCWs died during the study period. Death rates among males and females HCWs were nearly equivalent (51% vs. 49%). The majority were physicians and specialists (535, 35%), nurses (428, 28%), and midwives (359, 23%). Most deaths occurred between the ages of 40 to 59 years old, with the median age being 50 years (IQR: 39–59). At least 322 deaths (21%) occurred with pre-existing conditions, including 45 pregnant women. During the first 18 months of COVID-19 in Indonesia, we estimated a minimum HCW mortality rate of 1.707 deaths per 1,000 HCWs. The provincial rates of HCW mortality ranged from 0.136 (West Sulawesi) to 5.32 HCW deaths per 1,000 HCWs (East Java). The HCW mortality rate was significantly higher than that of the general population (RR = 4.92, 95% CI 4.67–5.17). The COVID-19 pandemic in Indonesia resulted in the loss of many hundreds of HCWs, the majority of whom were senior healthcare workers. The HCW mortality rate is five times that of the general population. A national systematic surveillance of occupational mortality is urgently needed in this setting.
Epidemiology of influenza in Ghana, 2011 to 2019
Authors: Asante Ivy Asantewaa , Fox Anne T. , Behene Eric , Awuku-Larbi Yaw , Kotey Erasmus Nikoi , Nyarko Stephen , Obeng Richard Asomadu , Arjarquah Augustina , Mawuli Gifty , Magnusen Vanessa , Attram Naiki Puplampu , Nimo-Paintsil Shirley , Asiedu-Bekoe Franklin , Laryea Dennis Odai , Bangdome Ofori Obed , Owusu Nyarko Edward , Lartei Mingle Daniel , Asiedu William , Letizia Andrew , Sanders Terrel , Ampofo William Kwabena
Published: December 2022

Influenza virus is an important contributor to acute respiratory illnesses and is estimated to cause up to 650,000 respiratory deaths each year. Ghana recorded influenza viruses as far back as 1918 when the Spanish influenza pandemic led to the death of >100,000 people in a population of 4 million at the time. An outbreak of highly pathogenic avian influenza A(H5N1) among poultry in Ghana in 2007, led to the establishment of virological surveillance for influenza-like illness (ILI) by the Noguchi Memorial Institute for Medical Research (NMIMR). This surveillance system, supported by the U.S. Naval Medical Research Unit-No. 3 (NAMRU-3) and the Ghana Health Service (GHS), monitors circulating influenza strains and activity to better understand the epidemiology of influenza in Ghana. We present here the results of this surveillance system from 2011 to 2019. As part of the Integrated Disease Surveillance and Response (IDSR) system of the GHS under the Ministry of Health (MOH), oropharyngeal and nasopharyngeal swabs were collected from patients who met a modified World Health Organization (WHO) case definition for ILI or severe acute respiratory illness (SARI) through a sentinel surveillance system in the country. Samples were transported to the National Influenza Centre (NIC) at the NMIMR and tested for influenza virus using protocols defined by the United States Centers for Disease Control and Prevention (CDC). Selected isolates were sent to the WHO collaborating centre in the United Kingdom for further antigenic characterization. From 2011 to 2019, the NIC tested a total of 21,747 ILI samples and 3,429 SARI samples. Influenza positivity rates were highest in the 5–14 year old group for both ILI (20.8%) and SARI (23.8%). Compared to females, more males were seen at the health facilities for ILI and SARI symptoms with a statistically significant difference in influenza positive ILI (15% vs 13.2%, p <0.001). In terms of absolute numbers, more cases were seen at the health centres during the wet seasons (April to October) compared to the dry seasons (November to March) in Ghana. This study presents 9 years of surveillance data from outpatient and inpatient setting on influenza activity as well as the influenza A subtypes and B lineages that drive the activity. This presents useful information for influenza vaccine selection and administration. Ghana’s unique influenza activity patterns also present a challenge in predicting when an outbreak could occur.
Classifying tasks performed by electrical line workers using a wrist-worn sensor: A data analytic approach
Authors: Ragani Lamooki Saeb , Hajifar Sahand , Hannan Jacqueline , Sun Hongyue , Megahed Fadel , Cavuoto Lora
Published: December 2022

Electrical line workers (ELWs) experience harsh environments, characterized by long shifts, remote operations, and potentially risky tasks. Wearables present an opportunity for unobtrusive monitoring of productivity and safety. A prerequisite to monitoring is the automated identification of the tasks being performed. Human activity recognition has been widely used for classification for activities of daily living. However, the literature is limited for electrical line maintenance/repair tasks due to task variety and complexity. We investigated how features can be engineered from a single wrist-worn accelerometer for the purpose of classifying ELW tasks. Specifically, three classifiers were investigated across three feature sets (time, frequency, and time-frequency) and two window lengths (4 and 10 seconds) to identify ten common ELW tasks. Based on data from 37 participants in a lab environment, two application scenarios were evaluated: (a) intra-subject, where individualized models were trained and deployed for each worker; and (b) inter-subject, where data was pooled to train a general model that can be deployed for new workers. Accuracies ≥ 93% were achieved for both scenarios, and increased to ≥96% with 10-second windows. Overall and class-specific feature importance were computed, and the impact of those features on the obtained predictions were explained. This work will contribute to the future risk mitigation of ELWs using wearables.
Women engagement in agriculture and human capital development in developing countries: An African sub-regional analysis
Authors: Matthew Oluwatoyin , Osabohien Romanus , Lakhani Kanwal Hammad , Aderounmu Busayo , Osadolor Nneka E. , Adediran Oluwasogo , Mabinuori Oladotun , Igharo Amechi E.
Published: December 2022

Considering the relevant role played by women in agriculture in Africa, this study sets out to examine how women’s engagement in agriculture contributes to human capital development in selected African countries. The study engagedpanel data of selected 33 African countries spanning the period of 2000 to 2019. The study applied the Pooled Ordinary Least Squares (POLS) and the fixed effects based on the Hausman specification. Findings show that engagement of women in agriculture, though significant, but negatively related to human capital development in Africa. The implication of this is that an increase in women’s engagement in agriculture without the required level of education and training and access to agricultural resources may have a negative impact on human capital development. Therefore, the study recommended that it is necessary to train women in terms of agricultural skills needed to improve human capital development in Africa.
Analysis and novel methods for capture of normative eye-tracking data in 2.5-month old infants
Authors: Gharib Alma , Thompson Barbara L.
Published: December 2022

Development of attention systems is essential for both cognitive and social behavior maturation. Visual behavior has been used to assess development of these attention systems. Yet, given its importance, there is a notable lack of literature detailing successful methods and procedures for using eye-tracking in early infancy to assess oculomotor and attention dynamics. Here we show that eye-tracking technology can be used to automatically record and assess visual behavior in infants as young as 2.5 months, and present normative data describing fixation and saccade behavior at this age. Features of oculomotor dynamics were analyzed from 2.5-month old infants who viewed videos depicting live action, cartoons, geometric shapes, social and non-social scenes. Of the 54 infants enrolled, 50 infants successfully completed the eye-tracking task and high-quality data was collected for 32 of those infants. We demonstrate that modifications specifically tailored for the infant population allowed for consistent tracking of pupil and corneal reflection and minimal data loss. Additionally, we found consistent fixation and saccade behaviors across the entire six-minute duration of the videos, indicating that this is a feasible task for 2.5-month old infants. Moreover, normative oculomotor metrics for a free-viewing task in 2.5-month old infants are documented for the first time as a result of this high-quality data collection.
Exploring the barriers and facilitators to accessing and utilising mental health services in regional, rural, and remote Australia: A scoping review protocol
Authors: Kavanagh Bianca E. , Beks Hannah , Versace Vincent L. , Quirk Shae E. , Williams Lana J.
Published: December 2022

Introduction

Australians from regional, rural, and remote areas face diverse and complex challenges in accessing and utilising mental health services. Previous research has pointed to a range of individual, community, structural, and systemic barriers at play, however, limited literature has synthesised the knowledge on this topic. Parallel to this, information on the facilitators to accessing and utilising mental health services for this group is not well documented. This protocol describes the methodology to undertake a scoping review, which aims to explore the barriers and facilitators associated with accessing and utilising mental health services in regional, rural, and remote Australia. In addition, the scoping review aims to geographically map the identified barriers and facilitators.

Methods

This protocol is guided by Arksey and O’Malley’s methodological framework. A search strategy will be developed and implemented to identify relevant peer-reviewed and grey literature. Studies will be included if they report on the barriers and/or facilitators associated with accessing and/or utilising mental health services in regional, rural, and remote Australia. Two reviewers will independently screen the data at the title/abstract and full-text stage. One reviewer will extract the relevant data using a predetermined charting form and a second reviewer will validate the included data. A Geographical Information System program will be used to map the location of the studies; locations will be stratified according to the Modified Monash Model and relationships between barriers and facilitators will be analysed. Key findings will be presented in a narrative account and in text, tables, and maps.

Discussion

This scoping review will provide a contemporary account on the barriers and facilitators to accessing and utilising mental health services for regional, rural, and remote Australians. It is anticipated that the results of this scoping review will have national policy relevance and may be useful to healthcare providers.
Association of muscle mass measured by D3-Creatine (D3Cr), sarcopenic obesity, and insulin-glucose homeostasis in postmenopausal women
Authors: Banack Hailey R. , LaMonte Michael J. , Manson JoAnn E. , Zhu Kexin , Evans William J. , Shankaran Mahalakshmi , Wactawski-Wende Jean
Published: December 2022

The D3-Creatine (D3Cr) dilution method is a direct and accurate measure of skeletal muscle mass. In this study, we examined the association of D3Cr muscle mass with measures of insulin-glucose homeostasis in community dwelling postmenopausal women. Additionally, we examined association of sarcopenic obesity, defined as low D3Cr muscle mass and high percent body fat, with fasting plasma glucose, insulin, hemoglobin A1c and insulin resistance. Insulin resistance was measured by the homeostatic measure of insulin resistance (HOMA-IR). This pilot study included 74 participants (mean age = 82.3 years) from the Women’s Health Initiative-Buffalo site. The D3Cr method was initiated at a clinic visit and used to measure muscle mass via remote urine sample collection. Descriptive and graphical approaches and age-adjusted linear regression models were used to analyze study data. We examined muscle mass as an absolute value (kg) and scaled to body weight (D3Cr muscle mass/kg). There was an inverse relationship between skeletal muscle mass, and impaired insulin-glucose homeostasis. Women with low muscle mass had higher levels of insulin (uIU/mL; β = -0.40; 95% CI: -0.79, -0.01), fasting plasma glucose (mg/dL; β = -0.1; 95% CI: -0.2, 0.03), HbA1c (%; β = -2.30; 95% CI: -5.7, 1.1), and calculated homeostatic model of insulin resistance, HOMA-IR, (β = -1.49; 95% CI: -2.9, -0.1). Sarcopenic obesity was common in this population of women; 41% of participants were categorized as having low muscle mass and high percent body fat. Results demonstrate that D3Cr muscle mass is independently associated with measures of insulin-glucose homeostasis, but obesity is a stronger predictor of insulin resistance than muscle mass.
Hybrid fuzzy inference rules of descent method and wavelet function for volatility forecasting
Authors: Alenezy Abdullah H. , Ismail Mohd Tahir , Jaber Jamil J. , Wadi S. AL , Alkhawaldeh Rami S.
Published: December 2022

This research employs the gradient descent learning (FIR.DM) approach as a learning process in a nonlinear spectral model of maximum overlapping discrete wavelet transform (MODWT) to improve volatility prediction of daily stock market prices using Saudi Arabia’s stock exchange (Tadawul) data. The MODWT comprises five mathematical functions and fuzzy inference rules. The inputs are the oil price (Loil) and repo rate (Repo) according to multiple regression correlation, and the Engle and Granger Causality test Engle RF, (1987). The logarithm of the stock market price (LSCS) in Tadawul reflects the output variable. The correlation matrix reveals that there is no collinearity between the input variables, and the causality test demonstrates that the input variables significantly influence the outcome variable. According to the multiple regression, there is a substantial negative influence between Loil and LSCS but a significant positive effect between Repo and output. For the 80% dataset under ME (0.000005), MAE (0.003214), and MAPE (0.064497), the MODWT-LA8 (ARIMA(1,1,0) with drift) for the LSCS variable performs better than other WT functions. In the novel hybrid model MODWT-FIR.DM, each function’s approximation coefficient (LSCS) is applied with input variables (Loil and Repo). We evaluate the performance of the proposed model (MODWT-LA8-FIR.DM) using different statistical measures (ME, RMSE, MAE, MPE) and compare it to two established models: the original FIR.DM and other MODWT-FIR.DM functions for forecasting 20% of datasets. The outcomes show that the MODWT-LA8-FIR.DM performs better than the traditional models based on lower ME (3.167586), RMSE (3.167638), MAE (3.167586), and MPE (80.860849). The proposed hybrid model may be a potential stock market forecasting model.