bluuebunny/crossref_metadata_2025 huggingface dataset:
Microstructure and Mechanical Properties of Functionally Graded AlSi/MWCNT Composite Cylinders
Authors: Pasha Azeem , Rajaprakash B.M.
Published: June 2023

Experimental fabrication of functionally graded Aluminum Silicon-carbon nanotubes (AlSi-MWCNT) reinforcement is significantly less, despite substantial theoretical interest. Many studies focused on axially layered functionally graded material because of ease of fabrication. Full advantage of AlSi-MWCNT functionally graded material only is taken when designed to the various shapes. In this research work, functionally graded cylinders were produced with 2wt% MWCNT at the outer surface to provide a complex and wear-resistant surface. The interior surface is soft with AlSi to provide elasticity. FGM1 sample indicates 112% and 11% increase in maximum tensile strength compared to AlSi and AlSi-MWCNT1wt%. FGM1 sample shows a 37% increase in elongation percentage compared to the AlSi-MWCNT1wt% composite. Test samples showing the typical nature of barrelling. FGM1 sample exhibits compressive strength of 237MPa, exceeding by 245% that of AlSi and by 3.5% that of AlSi-MWCNT1wt%. Three samples consider for each test. Hardness value ranges from 65HV at the core to 115HV at the outer surface. Hardness value Exceeds 56% in the outer layer compared to an inner region of FGM2.There is a proper bond between the layers, and the same demonstrate with properties of tensile, compressive, and hardness. OM with porosity, SEM with EDX evaluates to predict structural gradation in FGM cylinder. KEYWORDS: Aluminum silicon (AlSi) alloy; Functionally graded materials(FGM); Multi wall carbon nano tubes (MWCNT); Nano-composites; Thermo-mechanical processing
Antimicrobial activities of endophytic bacteria isolated from Ageratum conyzoides Linn.
Authors: BOONMAN NARUMON , CHUTRTONG JARUWAN , WANNA CHANATE , BOONSILP SIRIPHAN , CHUNCHOB SUPATRA
Published: June 2023

Abstract. Boonman N, Chutrtong J, Wanna C, Boonsilp S, Chunchob S. 2023. Antimicrobial activities of endophytic bacteria isolated from Ageratum conyzoides Linn. Biodiversitas 24: 1971-1979. Endophytic bacteria were isolated from various parts of Ageratum conyzoides Linn. Total 35 isolates were obtained which were consisting of eight isolates from the roots (AconR1-AconR8), nine isolates from the stems (AconS1-AconS9), seven isolates from the leaves (AconL1-AconL7) and 11 isolates from the flowers (AconF1-AconF11). These endophytic bacteria were examined for their antimicrobial activities against human pathogenic bacteria and fungi. The AconR2 and AconR4 inhibited the growth of Shigella flexneri and Salmonella enterica ser. typhi, whereas Escherichia coli was only inhibited by AconR2. For the antifungal activities assay, all isolated endophytic bacteria revealed no effect on Candida albicans, while six endophytic isolates exhibited more than 80% mycelial growth inhibition against Microsporum canis. These highly effective isolates were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The Bruker scores revealed that AconR2 and AconR4 were identified as Pseudomonas aeruginosa, AconS1 and AconS6 were classified as Enterobacter asburiae, Acon L5 and Acon F9 were identified as Bacillus cereus. The results indicated that these endophytic bacteria isolated from A. conyzoides effectively inhibited the growth of human pathogenic filamentous fungi and showed promise for further development as novel antifungal agents.
Genetic diversity and phylogenetic analysis of mayfly Caenis (Insecta: Ephemeroptera) using Cytochrome C Oxidase I (COI) and 12s rRNA genes from Thailand
Authors: PRAKRONGRAK NARUMON , BOONSOONG BOONSATIEN , MONTHATONG MONTHIRA
Published: June 2023

Abstract. Prakrongrak N, Boonsoong B, Monthatong M. 2023. Genetic diversity and phylogenetic analysis of mayfly Caenis (Insecta: Ephemeroptera) using Cytochrome C Oxidase I (COI) and 12s rRNA genes from Thailand. Biodiversitas 24: 1989-1997. Mayflies in genus Caenisis one of the top fifth species richnessbelonged to Family Caenidae. The present study aimed to use the partial mitochondrial Cytochrome COxidase subunit I (COI) and 12s rRNA nucleotide sequences for molecular species identification, diversity and phylogenetic relationships of mayflies in genus Caenis Stephens, 1835 species from Thailand. From a total of 37 specimens, thirteen nymphs were morphologically identified into five species: Caenis nasuta Malzacher, C. Picea Kimmins, C. ulmeriana Malzacher, C. cornigera Kang and Yang and C. longiforcipata Malzacher. The other 24 samples were Caenis sp.1 to sp.5. Partial COI sequences of all samples were compared with BOLD and GenBank for species identification. However, the result showed only genus-level identification as Caenis with greater than 80% similarity. For species delimitation, interspecific genetic distance among these species ranged from 14.4 to 26.6% (COI) and from 7.36 to 22.4% (12s rRNA). Intraspecific divergence levels were 0.0% to 2.35%. ABGD analysis of both genes divided data into 10 groups corresponding to 10 morphospecies of Caenis. The phylogenetic relationships of Caenis, COI and 12s rRNA genes also classified each species to well supported clusters. In addition, we report C. cornigera from Thailand for the first time. The COI and 12s rRNA phylogenetic trees indicate a close relationship between C. cornigera and C. longiforcipata, which is supported by their similar morphology.
A comparison between the ectomycorrhizal fungal communities associated with the natural and plantation populations of Dipterocarpus alatus
Authors: KAEWGRAJANG THARNRAT , YAMATO MASAHIDE , POLAMART THARIKA , SANGWANIT UTHAIWAN
Published: June 2023

Abstract. Kaewgrajang T, Yamato M, Polamart T, Sangwanit U. 2023. A comparison between the ectomycorrhizal fungal communities associated with the natural and plantation populations of Dipterocarpus alatus. Biodiversitas 24: 2088-2098. Dipterocarpus alatus Roxb. is a native tree species of Southeast Asian countries and one of the most economically important dipterocarp species. We investigated the ectomycorrhizal (ECM) fungi associated with D. alatus using molecular identifications on putative fruiting bodies and ECM roots collected from three natural forests and 10 D. alatus plantations. In this investigation, we aimed to report the ECM fungal communities of D. alatus in natural forests and plantations. Combining the results of fruiting bodies and ECM roots, 82 taxa belonging to 12 families were identified as ECM fungi. The ECM fungal community comprised many rare species and a few frequently found species. The Sebacina genus was found the most frequently in natural forests and plantations. The ECM fungal diversity was higher in plantations compared to natural forests. However, the frequently occurring ECM fungal taxa were not different between the natural forests and plantations. The result suggests that ECM fungal communities could be maintained in D. alatus plantations even if a reduction occurs in the natural population of dipterocarp forest.
Ant preference for different types of bait at sugarcane plantations in East Java, Indonesia
Authors: RAHARDJO BAMBANG TRI , MUHAMMAD FAIZ NASHIRUDDIN , SETIAWAN YOGO , FEBRYADI AKSHA , IHSAN MUHAMMAD , WIBOWO DENNIS , FERNANDO ITO
Published: June 2023

Abstract. Rahardjo BT, Muhammad FN, Setiawan Y, Febryadi A, Ihsan M, Wibowo D, Fernando I. 2023. Ant preference for different types of bait at sugarcane plantations in East Java, Indonesia. Biodiversitas 24:2099-2106. The occurrence of ants is important in agroecosystems since they may provide both ecosystem services or disservices depending on the species composition. Therefore, it is necessary to investigate the kind of ant species that are present in agroecosystems. This study aimed to assess the effectiveness of three types of bait to measure ant abundance and diversity in sugarcane plantations. This research was conducted from July to September 2022 in four locations in East Java, Indonesia, i.e., Karangploso, Kalipare, Gandusari, and Pasirian. At each location, one plot was determined and divided into nine subplots. Ant sampling was conducted using modified pitfall traps that may contain one type of bait or without bait as control treatment. There were three types of assayed bait, i.e., tuna, eggs, and sugar. Nine traps for each treatment were installed in each location. This study obtained 6,650 individual ants from 20 morphospecies, 16 genera, and 4 subfamilies. At each location, species richness and abundance were not significantly different among bait types. However, those variables differed between the bait groups and the control. Tuna and egg baits were preferred by ants, as indicated by the higher number of trapped individuals than in sugar bait and the control traps. The species composition of the different baits was different at all locations except Kalipare. Each ant species had a different preference for the type of bait. Formicine ants preferred sugar bait, while ponerine ants preferred tuna and egg baits. Hence, it can be concluded that the bait type selection needs to be considered for ant monitoring. Therefore, using various types of baits is recommended to monitor the assemblage of ants in an ecosystem.
Seaweed diversity and community structure on the west coast of Aceh, Indonesia
Authors: ERNIATI ERNIATI , ERLANGGA ERLANGGA , ANDIKA YUDHO , MULIANI MULIANI
Published: June 2023

Abstract. Erniati, Erlangga, Andika Y, Muliani. 2023. Seaweed diversity and community structure on the west coast of Aceh, Indonesia. Biodiversitas 24: 2189-2200. One of the commodities that continues to be developed by the Indonesian government in fisheries is seaweed. The potential of seaweed as a food ingredient in Aceh is very abundant. However, diversity and community structure of seaweeds on the west coast of Aceh have not been studied much. Therefore, this study has been carried out to assess the diversity and community structure of seaweeds on the west coast of Aceh based on transect method. Sampling has been carried out in all districts/cities (6 districts and 1 city) of west coast of Aceh. Altogether, a total of 50 species have been identified; of which, maximum number of species belongs to Phaeophyta (21 species) followed by Chlorophyta (16 species) and Rhodophyta (13 species). The estimated value of diversity (H'), uniformity (E), and dominance (D) index is 1.02, 0.50 and 0.51 respectively. Based on the univariate diversity indices analysis, it has been found that seaweed on the west coast of Aceh is in the moderate category. Furthermore, the water quality parameters revealed the existence of conducive environmental conditions for the growth and life of seaweed. So, it is proposed that use of appropriate seaweed culture techniques can be carried out on the west coast of Aceh to able to make Aceh a seaweed center in Indonesia.
Floristic composition and diversity of indigenous wild food resources in northwestern Cagayan, Philippines
Authors: CACATIAN SHELLA B. , TABIAN JOHN LESTER T.
Published: June 2023

Abstract. Cacatian SB, Tabian JLT. 2023. Floristic composition and diversity of indigenous wild food resources in Northwestern Cagayan, Philippines. Biodiversitas 24: 2324-2333. The indigenous knowledge of the floristic composition and the species diversity of wild food resources are primary indicators for wildlife management and conservation. The present study surveyed the ethnobotany of the indigenous wild plants, the possible environmental threats, and the traditional conservation practices of the rural people in the remote barangays of Sta. Praxedes, Claveria, Sanchez Mira, Pamplona and Abulug in Northwestern Cagayan, Philippines. The study employed a field-based cross-sectional design. Forty-eight wild plant species belonging to 42 families, mainly Moraceae, Solanaceae, Amaranthaceae and Cucurbitaceae, were harvested for food by the rural communities in the study areas. Among the identified species, trees and perennials were reported to be the most dominant. The most significant proportion grows in the lowland. Fruits and leaves are the most harvested plant parts consumed raw and or cooked. The phenological calendar was developed in relation to the specific months when the edible plant parts are available for harvest within the study sites. Agricultural land expansion or development, overexploitation of wildlife, and excessive rainfall are the greatest threats to plant diversity. Considering the importance of these food resources, the locals primarily keep and protect them from potential threats through harvesting and use of selected plants or plant parts, collecting firewood from dead and fallen trees, and domesticating and cultivating indigenous wild plants.
Effect of soil types on root infection of Acacia mangium and Eucalyptus pellita by Ganoderma philippii and Pyrrhoderma noxium
Authors: INDRAYADI HERU , GLEN MORAG , FAHRIZAWATI FAHRIZAWATI , SIREGAR BAYO ALHUSAERI , RIMBAWANTO ANTO , MARDAI MARDAI , TJAHJONO BUDI , MOHAMMED CAROLINE
Published: June 2023

Abstract. Indrayadi H, Glen M, Fahrizawati, Siregar BA, Rimbawanto A, Mardai, Tjahjono B, Mohammed C. 2023. Effect of soil types on root infection of Acacia mangium and Eucalyptus pellita by Ganoderma philippii and Pyrrhoderma noxium. Biodiversitas 24: 2358-2364. Acacia mangium Willd. and Eucalyptus pellita F.Muell. are susceptible to red root-rot disease, caused by Ganoderma philippii (Bres. & Henn. ex Sacc.) Bres., has led to the demise of planted A. mangium as a commercial pulpwood in Indonesia. A second root-rot pathogen, Pyrrhoderma noxium (Corner) L.W.Zhou & Y.C.Dai (syn. Phellinus noxius (Corner) G.Cunn.), also attacks both species. The objective of this study was to investigate the effect of different soil types on the root infection of A. mangium and E. pellita by G. philippii and P. noxium. The effect of three contrasting soil types (mineral R41, R51 and peat soil) used in a plantation estate in Riau province on disease development was investigated in a pot trial using four isolates, two of G. philippii and two of P. noxium. Two models of inoculation were used, in one of which inoculated wood blocks were placed against the seedling roots (Model 1), the second where the blocks were 10-20 cm from the roots (Model 2). Fifty weeks after the experiment was established, mortality was significantly higher in the soil of low than high clay content, in A. mangium than E. pellita, and in Model 1 than Model 2; there was no difference between the two G. philippii isolates, and P. noxium did not cause any mortality. G. philippii inoculum could survive in all three soil types for over 9 months; hence, the effect of soil type was not mediated by inoculum longevity. Alternatives should be pursued to limit further development of root-rot diseases in existing E. pellita estates.
Diversity of endophytic fungi of rice plants in Padang City, Indonesia, entomopathogenic to brown planthopper (Nilaparvata lugens)
Authors: TRIZELIA TRIZELIA , RAHMA HALIATUR , SYAHRAWATI MY
Published: June 2023

Abstract. Trizelia, Rahma H, Syahrawati M. 2023. Diversity of endophytic fungi of rice plants in Padang City, Indonesia, entomopathogenic to brown planthopper (Nilaparvata lugens). Biodiversitas 24: 2384-2392. Various endophytic fungi can live in plant tissues for all or part of their life cycle without causing damage or disease in their host. Several genera of endophytic fungi have been reported to be entomopathogenic and can be used to control insect pests. This study aimed to determine the diversity of endophytic fungi from rice stems that were entomopathogenic against Nilaparvata lugens (Stål, 1854) or Brown Planthopper (BPH). Endophytic fungi were isolated from rice stems of IR42 and Cisokan varieties grown in Padang City, West Sumatra Indonesia. Isolated fungi were first evaluated for their pathogenicity against Tenebrio molitor larvae. Subsequently high pathogenicity showed isolates were tested on nymphs and adults of BPH. The results showed that the entomopathogenic fungi isolated from IR 42 and Cisokan were the members of genus Aspergillus, Trichoderma, and Beauveria. The entomopathogenic fungi from IR 42 were more diverse than Cisokan, and Beauveria sp. was the most common isolate and had a better ability to kill the BPH. The highest mortality of BPH was found in PIR 1.3 isolate, but the mortality was still relatively low (53.33% nymphs and 34.99% adults). Further study is needed to increase the effectiveness of these endophytic fungi against BPH directly or indirectly by inducing resistance.
Participation of community in mangrove conservation in coastal area of the Valentine Strait, West Seram, Maluku, Indonesia
Authors: AIPASSA MARLON I. , SIAHAYA MARTHA E. , APONNO HENDRIK S.E.S. , RUSLIM YOSEP , KRISTININGRUM ROCHADI
Published: June 2023

Abstract. Aipassa MI, Siahaya ME, Aponno HSES, Ruslim Y, Kristiningrum R. 2023. Participation of community in mangrove conservation in coastal area of the Valentine Strait, West Seram, Maluku, Indonesia. Biodiversitas 24: 2467-2474. A mangrove forest is composed of mangrove plants and constitutes a crucial ecosystem in coastal areas. It is a vital source for maintaining aquatic ecosystems between the sea, coast, and land. Additionally, it provides benefits to humans, such as contributing to a more comfortable climate and weather conditions that can prevent natural disasters. However, the mangrove in the Valentine Strait area (West Seram, Maluku, Indonesia) is threatened by land conversion, leading to damage and loss. Some people are trying to preserve and maintain mangrove in their area. Therefore, the aim of this research was to describe the actions of the local community in the area, using the concept of cultural capital. A combination of qualitative and quantitative methods was used, and both primary and secondary data were collected. Primary data were gathered directly from the research location, while secondary data were obtained through local community information, various websites, and documents related to the management of natural resources. Additionally, key informants, including local community leaders, Kewang, and LPPM Maluku (NGO), were interviewed to collect relevant data on the cultural capital possessed by the community. The data for identifying mangrove species were calculated and tabulated to determine the species density in the Valentine Strait area. Furthermore, the collected community data were analyzed using cultural capital theory. The results indicate that community has started to reapply the concept of cultural capital of the Sasi tradition as ecological knowledge to maintain and preserve mangrove; hence, ensuring conservation in the Valentine Strait area. Mangrove forests have become home to fish, shrimp, and crabs and are also important for birds, primates, and reptiles.
Wavefront measurements using the Ronchi test for high-NA lithography projection lenses
Authors: Yu Xinfeng , Li Jiaqi
Published: June 2023

The Ronchi test is widely used for wavefront measurements in advanced lithography tools, and a physical optics explanation of the Ronchi test based on scalar diffraction theory can be found in numerous publications. However, for high-numerical aperture (high-NA) lithography projection lenses, the vector nature of light should be considered when performing wavefront measurements, especially the effect of polarization aberrations on the wavefront test results. In this paper, a vector model for describing shearing interferometry for high-NA lithography projection lenses is established. In addition to considering the vector nature of light, the vector model also calculates the Ronchigram on the screen of a detector at any distance from a diffraction grating, as opposed to the distance restriction for the Fraunhofer diffraction approximation used by the existing methods. Using the developed mathematical model of the Ronchi test, the Ronchigrams of high-NA lithography projection lenses under non-polarized illumination are simulated, and the effect of the distance between the diffraction grating and the detection screen on the wavefront measurement accuracy are discussed.
Compact and efficient polarization rotator using laterally asymmetric rib waveguides on a lithium-niobate-on-insulator platform
Authors: Wang Qifeng , Xiao Jinbiao
Published: June 2023

Photonic devices based on a lithium-niobate-on-insulator (LNOI) are
current research hotspots; however, owing to the high refractive index
contrast of the LNOI platform and inherent birefringence of lithium
niobate itself, such photonic devices are generally polarization
sensitive, affecting their further wide application. This paper
proposes a simple, compact, and efficient polarization rotator (PR)
based on a laterally asymmetric rib waveguide by depositing a layer of
semi-infinite silicon nitride dielectric material on one side of the
rib waveguide. The results show that a PR with a polarization rotation
region length of 15.77 µm is achieved, and the polarization
extinction ratio (PER), insertion loss (IL), and polarization
conversion efficiency (PCE) are 38.57/68.95 and 0.2/0.22 dB,
and 99.99%/almost 100%, respectively, for the fundamental transverse
electric mode (TE0) and transverse magnetic mode (TM0) at a 1.55 µm wavelength. The
operation bandwidth is around 120 nm for the TE0 mode and TM0 mode when the PER, IL, and PCE are
greater than 20 dB, less than 0.32 dB, and more than
99%, respectively. Fabrication tolerances to the key structural
parameters are investigated in detail. In addition, the evolution
fields of the TE0 mode and TM0 mode along the propagation direction
through the proposed device are presented.
Automated inter-device 3D OCT image registration using deep learning and retinal layer segmentation
Authors: Rivas-Villar David , Motschi Alice R. , Pircher Michael , Hitzenberger Christoph K. , Schranz Markus , Roberts Philipp K. , Schmidt-Erfurth Ursula , Bogunović Hrvoje
Published: June 2023

Optical coherence tomography (OCT) is the most widely used imaging modality in ophthalmology. There are multiple variations of OCT imaging capable of producing complementary information. Thus, registering these complementary volumes is desirable in order to combine their information. In this work, we propose a novel automated pipeline to register OCT images produced by different devices. This pipeline is based on two steps: a multi-modal 2D en-face registration based on deep learning, and a Z-axis (axial axis) registration based on the retinal layer segmentation. We evaluate our method using data from a Heidelberg Spectralis and an experimental PS-OCT device. The empirical results demonstrated high-quality registrations, with mean errors of approximately 46 µm for the 2D registration and 9.59 µm for the Z-axis registration. These registrations may help in multiple clinical applications such as the validation of layer segmentations among others.
Generation of stable propagation Bessel beams and axial multifoci beams with binary amplitude filters
Authors: Zhang Xin , Zhang Xiao-Tong , Ye Jia-Sheng , Feng Sheng-Fei , Wang Xin-Ke , Han Peng , Sun Wen-Feng , Zhang Yan
Published: June 2023

The binary amplitude filter (BAF) is employed to generate stable propagation Bessel beams and axial multifoci beams, rather than the traditional continuous amplitude filter (CAF). We introduce a parameter along the azimuth direction, i.e., angular order of the BAF, to weaken transverse intensity asymmetry. Numerical simulations reveal that the BAF implements the same optical functionalities as the CAF. The BAF holds advantages over the traditional CAF: a simpler fabrication process, a lower cost, and a higher experimental accuracy. It is believed that the BAF should have many practical applications in future optical systems.
Spatial-mode demultiplexing for enhanced intensity and distance measurement
Authors: Santamaria Luigi , Pallotti Deborah , Siciliani de Cumis Mario , Dequal Daniele , Lupo Cosmo
Published: June 2023

Spatial-mode demultiplexing (SPADE) has recently been adopted to measure the separation in the transverse plane between two incoherent point-like sources with sub-wavelength separation. It has been argued that this approach may yield extraordinary performances in the photon-counting regime. Here, we explore SPADE as a tool for precision measurements in the regime of bright, incoherent sources. First we analyze the general problem of estimating the second moments of the source’s intensity distribution, for an extended incoherent source of any shape. Our theory predicts a substantial improvement in signal-to-noise ratio (SNR) of SPADE over direct imaging in the sub-wavelength regime. Second, we present an experimental application of SPADE to the case of two point-like, bright sources. We demonstrate the use of this setup for the estimation of the transverse separation and for the estimation of the relative intensity, confirming the expected improvement in SNR.
Underwater active polarization descattering based on a single polarized image
Authors: Li Haoxiang , Zhu Jingping , Deng Jinxin , Guo Fengqi , Zhang Ning , Sun Jian , Hou Xun
Published: June 2023

Active polarization imaging techniques have tremendous potential for a variety of underwater applications. However, multiple polarization images as input are necessary for almost all methods, thereby limiting the range of applicable scenarios. In this paper, via taking full advantage of the polarization feature of target reflective light, the cross-polarized backscatter image is reconstructed via introducing an exponential function for the first time, only based on mapping relations of co-polarized image. Compared with rotating the polarizer, the result performs a more uniform and continuous distribution of grayscale. Furthermore, the relationship of degree of polarization (DOP) between the whole scene and backscattered light is established. This leads to an accurate estimation of backscattered noise and high-contrast restored images. Besides, single-input greatly simplifies the experimental process and upgrades efficiency. Experimental results demonstrate the advancement of the proposed method for objects with high polarization under various turbidities.
High-throughput doubly-encoded single-pixel spectrometer with an extended aperture
Authors: Yu Chew Jeremy Xuan , Lim Zi Heng , Qi Yi , Zhou Guangcan , Zhou Guangya
Published: June 2023

Infrared devices are increasingly used in industrial, medical, and environmental monitoring applications. Cost-effectiveness, robustness, and portability are characteristics that are highly sought after and they can be enabled by a dispersive spectrometer carrying a single-pixel detector. In this paper, we demonstrate a novel, high-throughput dispersive spectrometer that has its spectral resolution decoupled from its throughput. The proposed spectrometer implements a two-stage Hadamard transform encoding process that allows significantly more light into the system to enhance its signal-to-noise ratio. As a single-pixel detector is used to collect the spectral information, the proposed system can be easily implemented in other desired wavelengths. Furthermore, we develop a method to remove the need for uniform illumination at the entrance aperture by taking into consideration its spatial information during the reconstruction process, thereby increasing the ease of the design of devices required for in situ measurement.
Image distortion by ambiguous multiple-photon detections in a superconducting nanowire single-photon imager and the correction method
Authors: Wang Hui , Li Zhi-jian , Hu Xue-Mei , Hao Hao , Guo Jia-wei , Huang Yang-hui , Liu Hao , Wan Chao , Tu Xue-cou , Jia Xiao-qing , Zhang La-bao , Chen Jian , Kang Lin , Yue Tao , Zhao Qing-yuan , Wu Pei-heng
Published: June 2023

Scaling up superconducting nanowire single-photon detectors (SNSPDs) into a large array for imaging applications is the current pursuit. Although various readout architectures have been proposed, they cannot resolve multiple-photon detections (MPDs) currently, which limits the operation of the SNSPD arrays at high photon flux. In this study, we focused on the readout ambiguity of a superconducting nanowire single-photon imager applying time-of-flight multiplexing readout. The results showed that image distortion depended on both the incident photon flux and the imaging object. By extracting multiple-photon detections on idle pixels, which were virtual because of the incorrect mapping from the ambiguous readout, a correction method was proposed. An improvement factor of 1.3~9.3 at a photon flux of µ = 5 photon/pulse was obtained, which indicated that joint development of the pixel design and restoration algorithm could compensate for the readout ambiguity and increase the dynamic range.
Optoelectronic and mechanical properties of microstructured polymer optical fiber neural probes
Authors: Sui Kunyang , Meneghetti Marcello , Berg Rune W. , Markos Christos
Published: June 2023

Multifunctional optical fiber-based neural interfaces have attracted significant attention for neural stimulation, recording, and photopharmacology towards understanding the central nervous system. In this work, we demonstrate the fabrication, optoelectrical characterization, and mechanical analysis of four types of microstructured polymer optical fiber neural probes using different soft thermoplastic polymers. The developed devices have integrated metallic elements for electrophysiology and microfluidic channels for localized drug delivery, and can be used for optogenetics in the visible spectrum at wavelengths spanning from 450 nm up to 800 nm. Their impedance, measured by electrochemical impedance spectroscopy, was found to be as low as 21 kΩ and 4.7 kΩ at 1kHz when indium and tungsten wires are used as the integrated electrodes, respectively. Uniform on-demand drug delivery can be achieved by the microfluidic channels with a measured delivery rate from 10 up to 1000 nL/min. In addition, we identified the buckling failure threshold (defined as the conditions for successful implantation) as well as the bending stiffness of the fabricated fibers. Using finite element analysis, we calculated the main critical mechanical properties of the developed probes to avoid buckling during implantation and maintain high flexibility of the probe within the tissue. Our results aim to demonstrate the impact of design, fabrication, and characteristics of the materials on the development of polymer fibers as next-generation implants and neural interfaces.
Investigation on the thermal aberration of Nd:YAG on SiC fabricated by room temperature bonding with a Mo/Au nano-interlayer
Authors: Deng Ningkang , Qu Yongfeng , Yuan Jin , Yuan Yuan , Hu Wenbo , Zhang Zhaoyang , Wu Shengli , Wang Hongxing
Published: June 2023

To improve the thermal performance of Nd:YAG lasers, a Nd:YAG laser crystal is bonded on a SiC wafer by atomic diffusion bonding (ADB) via a Mo/Au nano-interlayer at room temperature. In addition, a two-dimensional model of the Nd:YAG-SiC with a Mo/Au nano-interlayer is developed to investigate the thermal aberration and temperature distribution inside the Nd:YAG. The result shows that the bonded Nd:YAG-SiC exhibits an extremely low voidage, along with a 106-nm-thick metal interlayer. The simulation reveals that the Nd:YAG-SiC has a maximum temperature of 393.3 K with a reduction of 28.5 K and a less thermal aberration near the axis compared to the Nd:YAG-CuW at a pump power density of 5 kW/cm2.
Interferometer response characterization algorithm for multi-aperture Fabry-Perot imaging spectrometers
Authors: Picone Daniele , Gousset Silvère , Mura Mauro Dalla , Ferrec Yann , le Coarer Etienne
Published: June 2023

In recent years, the demand for hyperspectral imaging devices has grown significantly, driven by their ability of capturing high-resolution spectral information. Among the several possible optical designs for acquiring hyperspectral images, there is a growing interest in interferometric spectral imaging systems based on division of aperture. These systems have the advantage of capturing snapshot acquisitions while maintaining a compact design. However, they require a careful calibration to operate properly. In this work, we present the interferometer response characterization algorithm (IRCA), a robust three-step procedure designed to characterize the transmittance response of multi-aperture imaging spectrometers based on the interferometry of Fabry-Perot. Additionally, we propose a formulation of the image formation model for such devices suitable to estimate the parameters of interest by considering the model under various regimes of finesse. The proposed algorithm processes the image output obtained from a set of monochromatic light sources and refines the results using nonlinear regression after an ad-hoc initialization. Through experimental analysis conducted on four different prototypes
from the Image SPectrometer On Chip (ImSPOC) family, we validate the performance of our approach for characterization. The associated source code for this paper is available at https://github.com/danaroth83/irca.
Stochastic reconstruction of dual components facilitates high-fidelity in vivo fluorescence tomographic imaging
Authors: Ren Wuwei , Zhang Jianru , Hu Qian , Li Linlin , Gao Shengyu , Wu Yanan , Gu Liangtao , Li Jianfeng , Chen Liang , Zhu Xingjun , Jiang Jiahua
Published: June 2023

Wide-field fluorescence imaging is an indispensable tool for longitudinal animal studies. However, light scattering in tissue imposes a fundamental challenge for accurately localizing and quantifying fluorophore distribution in depth. Conventional regularization-assisted reconstruction paradigm can mitigate the ill-posedness of the inverse problem, but results in low-resolution images and is vulnerable to the interference of background signal. We herein introduce a dual-component fluorescence molecular tomography (DC-FMT) scheme to non-invasively discern the 3D fluorophore distribution resolved into two distinct stochastic components, i.e., a smoothly fluctuating background and a sparsely distributed target. DC-FMT possesses the exclusive advantage of solution decomposition hybrid projection method, and enables fully automated, efficient and high-resolution reconstruction, as systematically validated through proof-of-concept studies on both phantom and animal models. Our method represents an advanced reconstruction scheme incorporating more comprehensive prior information, thus unlocking a wide range of applications in fluorescence-guided diagnostics and surgeries.
The novel anti-phage system Shield co-opts an RmuC domain to mediate phage defense across Pseudomonas species
Authors: Macdonald Elliot , Wright Rosanna , Connolly James P. R. , Strahl Henrik , Brockhurst Michael , van Houte Stineke , Blower Tim R. , Palmer Tracy , Mariano Giuseppina
Published: June 2023

Competitive bacteria-bacteriophage interactions have resulted in the evolution of a plethora of bacterial defense systems preventing phage propagation. In recent years, computational and bioinformatic approaches have underpinned the discovery of numerous novel bacterial defense systems. Anti-phage systems are frequently encoded together in genomic loci termed defense islands. Here we report the identification and characterisation of a novel anti-phage system, that we have termed Shield, which forms part of the Pseudomonas defensive arsenal. The Shield system comprises the core component ShdA, a membrane-bound protein harboring an RmuC domain. Heterologous production of ShdA alone is sufficient to mediate bacterial immunity against several phages. We demonstrate that Shield and ShdA confer population-level immunity and that they can also decrease transformation efficiency. We further show that ShdA homologues can degrade DNA in vitro and, when expressed in a heterologous host, can alter the organisation of the host chromosomal DNA. Use of comparative genomic approaches identified how Shield can be divided into four subtypes, three of which contain additional components that in some cases can negatively affect the activity of ShdA and/or provide additional lines of phage defense. Collectively, our results identify a new player within the Pseudomonas bacterial immunity arsenal that displays a novel mechanism of protection, and reveals a role for RmuC domains in phage defense.
Geographic mobility and treatment outcomes among people in care for tuberculosis in the Lake Victoria region of East Africa: A multi-site prospective cohort study
Authors: Mulholland Grace E. , Herce Michael E. , Bahemuka Ubaldo M. , Kwena Zachary A. , Jeremiah Kidola , Okech Brenda A. , Bukusi Elizabeth , Okello Elialilia S. , Nanyonjo Gertrude , Ssetaala Ali , Seeley Janet , Emch Michael , Pettifor Audrey , Weir Sharon S. , Edwards Jessie K.
Published: June 2023

Geographic mobility may disrupt continuity of care and contribute to poor clinical outcomes among people receiving treatment for tuberculosis (TB). This may occur especially where health services are not well coordinated across international borders, particularly in lower and middle income country settings. In this work, we describe mobility and the relationship between mobility and unfavorable TB treatment outcomes (i.e., death, loss to follow-up, or treatment failure) among a cohort of adults who initiated TB treatment at one of 12 health facilities near Lake Victoria. We abstracted data from health facility records for all 776 adults initiating TB treatment during a 6-month period at the selected facilities in Kenya, Tanzania, and Uganda. We interviewed 301 cohort members to assess overnight travel outside one’s residential district/sub-county. In our analyses, we estimated the proportion of cohort members traveling in 2 and 6 months following initiation of TB treatment, explored correlates of mobility, and examined the association between mobility and an unfavorable TB treatment outcome. We estimated that 40.7% (95% CI: 33.3%, 49.6%) of people on treatment for TB traveled overnight at least once in the 6 months following treatment initiation. Mobility was more common among people who worked in the fishing industry and among those with extra-pulmonary TB. Mobility was not strongly associated with other characteristics examined, however, suggesting that efforts to improve TB care for mobile populations should be broad ranging. We found that in this cohort, people who were mobile were not at increased risk of an unfavorable TB treatment outcome. Findings from this study can help inform development and implementation of mobility-competent health services for people with TB in East Africa.
Dengue in Myanmar: Spatiotemporal epidemiology, association with climate and short-term prediction
Authors: Zaw Win , Lin Zaw , Ko Ko July , Rotejanaprasert Chawarat , Pantanilla Neriza , Ebener Steeve , Maude Richard James
Published: June 2023

Dengue is a major public health problem in Myanmar. The country aims to reduce morbidity by 50% and mortality by 90% by 2025 based on 2015 data. To support efforts to reach these goals it is important to have a detailed picture of the epidemiology of dengue, its relationship to meteorological factors and ideally to predict ahead of time numbers of cases to plan resource allocations and control efforts. Health facility-level data on numbers of dengue cases from 2012 to 2017 were obtained from the Vector Borne Disease Control Unit, Department of Public Health, Myanmar. A detailed analysis of routine dengue and dengue hemorrhagic fever (DHF) incidence was conducted to examine the spatial and temporal epidemiology. Incidence was compared to climate data over the same period. Dengue was found to be widespread across the country with an increase in spatial extent over time. The temporal pattern of dengue cases and fatalities was episodic with annual outbreaks and no clear longitudinal trend. There were 127,912 reported cases and 632 deaths from 2012 and 2017 with peaks in 2013, 2015 and 2017. The case fatality rate was around 0.5% throughout. The peak season of dengue cases was from May to August in the wet season but in 2014 peak dengue season continued until November. The strength of correlation of dengue incidence with different climate factors (total rainfall, maximum, mean and minimum temperature and absolute humidity) varied between different States and Regions. Monthly incidence was forecasted 1 month ahead using the Auto Regressive Integrated Moving Average (ARIMA) method at country and subnational levels. With further development and validation, this may be a simple way to quickly generate short-term predictions at subnational scales with sufficient certainty to use for intervention planning.
Evidence-based advice on timing and location of tsetse control measures in Shimba Hills National reserve, Kenya
Authors: Gachoki Stella , Groen Thomas A. , Vrieling Anton , Skidmore Andrew , Masiga Daniel
Published: June 2023

Controlling tsetse flies is critical for effective management of African trypanosomiasis in Sub-Saharan Africa. To enhance timely and targeted deployment of tsetse control strategies a better understanding of their temporal dynamics is paramount. A few empirical studies have explained and predicted tsetse numbers across space and time, but the resulting models may not easily scale to other areas. We used tsetse catches from 160 traps monitored between 2017 and 2019 around Shimba Hills National Reserve in Kenya, a known tsetse and trypanosomiasis hotspot. Traps were divided into two groups: proximal (<1.0 km)) to and distant (> 1.0 km) from the outer edge of the reserve boundary. We fitted zero-inflated Poisson and generalized linear regression models for each group using as temporal predictors rainfall, NDVI (Normalized Difference Vegetation Index), and LST (land surface temperature). For each predictor, we assessed their relationship with tsetse abundance using time lags from 10 days up to 60 days before the last tsetse collection date of each trap. Tsetse numbers decreased as distance from the outside of reserve increased. Proximity to croplands, grasslands, woodlands, and the reserve boundary were the key predictors for proximal traps. Tsetse numbers rose after a month of increased rainfall and the following increase in NDVI values but started to decline if the rains persisted beyond a month for distant traps. Specifically, tsetse flies were more abundant in areas with NDVI values greater than 0.7 for the distant group. The study suggests that tsetse control efforts beyond 1.0 km of the reserve boundary should be implemented after a month of increased rains in areas having NDVI values greater than 0.7. To manage tsetse flies effectively within a 1.0 km radius of the reserve boundary, continuous measures such as establishing an insecticide-treated trap or target barrier around the reserve boundary are needed.
Effects of T cell leptin signaling on systemic glucose tolerance and T cell responses in obesity
Authors: Kiernan Kaitlin , Nichols Amanda G. , Alwarawrah Yazan , MacIver Nancie J.
Published: June 2023

Background/Objectives

Leptin is an adipokine secreted in proportion to adipocyte mass and is therefore increased in obesity. Leptin signaling has been shown to directly promote inflammatory T helper 1 (Th1) and T helper 17 (Th17) cell number and function. Since T cells have a critical role in driving inflammation and systemic glucose intolerance in obesity, we sought to determine the role of leptin signaling in this context.

Methods

Male and female T cell-specific leptin receptor knockout mice and littermate controls were placed on low-fat diet or high-fat diet to induce obesity for 18 weeks. Weight gain, serum glucose levels, systemic glucose tolerance, T cell metabolism, and T cell differentiation and cytokine production were examined.

Results

In both male and female mice, T cell-specific leptin receptor deficiency did not reverse impaired glucose tolerance in obesity, although it did prevent impaired fasting glucose levels in obese mice compared to littermate controls, in a sex dependent manner. Despite these minimal effects on systemic metabolism, T cell-specific leptin signaling was required for changes in T cell metabolism, differentiation, and cytokine production observed in mice fed high-fat diet compared to low-fat diet. Specifically, we observed increased T cell oxidative metabolism, increased CD4+ T cell IFN-γ expression, and increased proportion of T regulatory (Treg) cells in control mice fed high-fat diet compared to low-fat diet, which were not observed in the leptin receptor conditional knockout mice, suggesting that leptin receptor signaling is required for some of the inflammatory changes observed in T cells in obesity.

Conclusions

T cell-specific deficiency of leptin signaling alters T cell metabolism and function in obesity but has minimal effects on obesity-associated systemic metabolism. These results suggest a redundancy in cytokine receptor signaling pathways in response to inflammatory signals in obesity.
A parasite DNA binding protein with potential to influence disease susceptibility acts as an analogue of mammalian HMGA transcription factors
Authors: Durrani Zeeshan , Kinnaird Jane , Cheng Chew Weng , Brühlmann Francis , Capewell Paul , Jackson Andrew , Larcombe Stephen , Olias Philipp , Weir William , Shiels Brian
Published: June 2023

Intracellular pathogens construct their environmental niche, and influence disease susceptibility, by deploying factors that manipulate infected host cell gene expression. Theileria annulata is an important tick-borne parasite of cattle that causes tropical theileriosis. Excellent candidates for modulating host cell gene expression are DNA binding proteins bearing AT-hook motifs encoded within the TashAT gene cluster of the parasite genome. In this study, TashAT2 was transfected into bovine BoMac cells to generate three expressing and three non-expressing (opposite orientation) cell lines. RNA-Seq was conducted and differentially expressed (DE) genes identified. The resulting dataset was compared with genes differentially expressed between infected cells and non-infected cells, and DE genes between infected cell lines from susceptible Holstein vs tolerant Sahiwal cattle. Over 800 bovine genes displayed differential expression associated with TashAT2, 209 of which were also modulated by parasite infection. Network analysis showed enrichment of DE genes in pathways associated with cellular adhesion, oncogenesis and developmental regulation by mammalian AT-hook bearing high mobility group A (HMGA) proteins. Overlap of TashAT2 DE genes with Sahiwal vs Holstein DE genes revealed that a significant number of shared genes were associated with disease susceptibility. Altered protein levels encoded by one of these genes (GULP1) was strongly linked to expression of TashAT2 in BoMac cells and was demonstrated to be higher in infected Holstein leucocytes compared to Sahiwal. We conclude that TashAT2 operates as an HMGA analogue to differentially mould the epigenome of the infected cell and influence disease susceptibility.