bluuebunny/crossref_metadata_2025 huggingface dataset:
3D Rendering Pipeline for a High-speed Line-field Optical Coherence Tomography System
Authors: Yang Xingyu , Zhang Zijian , Lawman Samuel , Zhu Xinjie , Zheng Yalin , Shen Yaochun
Published: August 2024

We provide a full solution for creating 3D models using a 100k Hz A-line rate line-field OCT system. The generated models have a 50-fold reduction of data size and can be exported for AR/VR and 3D printing.
Phase-only Digital Holography for Illumination Using a Single Computer-Generated Hologram (CGH)
Authors: Gao Phoebe Xin , Deng Yuanbo , Chu Daping
Published: August 2024

Computer-generated hologram (CGH) is optimised for using a single phase-only hologram achieving white light illumination, reducing colour dispersion and improving image quality. It explores coherence, speckles, and the impact of LCoS sizes on illumination performance.
Self-assembling of polymeric microstructures
Authors: Coppola Sara , Fontanarosa Giuseppe , Miccio Lisa , Vespini Veronica , Grilli Simonetta , Incardona Nicolò , D’Avino Gaetano , Maffettone Pier Luca , Ferraro Pietro
Published: August 2024

The fabrication of polymeric microstructures has gained a lot of interest because of high flexibility in terms of geometry, dimension and reduced costs. Microstructures could find application in various technological fields such as optics, biomedicine, microfluidics and the functionalization of intelligent devices. Here we propose the study of self-assembling process for the formation of polymeric bumps integrated with a multiphysics analysis.
Measurement of internal defects in Quartz glass using in-line digital holographic microscopy
Authors: Shan Mingguang , Guo Jianchao , Zhong Zhi , Liu Bin , Yu Lei , Liu Lei
Published: August 2024

A method for detecting internal defects in quartz glass using digital holography technology is proposed and verified by experiment.
3D Visualization of Phytoplankton via In-Flow Digital Holographic Tomography
Authors: Borrelli Francesca , Giugliano Giusy , Pirone Daniele , Behal Jaromir , Zupo Valerio , Amoroso Mariano , Costantini Maria , Sardo Angela , Miccio Lisa , Memmolo Pasquale , Bianco Vittorio , Ferraro Pietro
Published: August 2024

We use in-flow digital holographic tomography to perform the 3D visualization of phytoplankton as a label free, quantitative, high throughput investigation technique of these samples known to be natural bio-sensors for water quality assays.
Cost-Effective, DIY, and Open-Source Digital Lensless Holographic Microscope with Distortion Correction
Authors: Buitrago-Duque C. , Tobón-Maya H. , Garcia-Sucerquia J.
Published: August 2024

A cost-effective, DIY, and open-source certifiable digital lensless holographic microscope (DLHM) is presented. The proposed microscope reduces the flaws regularly found when budget laser diodes and aspherical lenses are utilized in compact setups.
Amnis Image Stream-Analysis of Tumor Cells
Authors: Mugnano Martina , Wang Zhe , Cerbone Vincenza , Scalia Giulia , Montella Annalaura , Capasso Mario , Mari Silvia , Ferranti Francesca , Pirone Daniele , Valentino Marika , Miccio Lisa , Maffettone Pier Luca
Published: August 2024

Imaging flow cytometry is a cutting-edge technology for analyzing cell features. Here we show the advantage of using this system to study cell nucleus of tumor cells, using ovarian cancer A2780 cell line as model. Amnis Image stream it has been used as a standard comparison tool respect to quantitative phase imaging to study cell features.
Multimodal Optical Microscopy for Oral Cancer Screening
Authors: Thapa Pramila , Bhatt Sunil , Joshi Himanshu , Butola Ankit , Surya Varun , Mishra Deepika , Mehta Dalip Singh
Published: August 2024

A multi-modality system can reduce the fatality rate of oral cancer and increase diagnostic-accuracy. In this paper, autofluorescence and quantitative-phase microscopy were used simultaneously to use a multi-modal optical approach for oral cancer screening.
Dual-wavelength, near-infrared holographic tomography
Authors: Kuś Arkadiusz
Published: August 2024

Dual wavelength interferometry has a long history and broad range of applications in optical measurements of objects, which exhibit phase steps greater than the single measurement wavelength [1–3]. The use of two measurements at slightly different wavelengths allows to extend the measurement range. In case of holographic tomography, the standard measurement of large samples such as organoids fails due to large refractive index differences and phase unwrapping errors. The application of synthetic wavelength allows to decrease the values of phase of the scattered wave for the synthetic wavelength and thus apply Born approximation to objects that exceed the π/2 phase for each of the constituent measurements. In this work holographic tomography is performed with a swept laser source, which additionally allows to fine-tune the synthetic wavelength.
Optical Asymmetric Color Image Encryption using Vector Light Field Encoding
Authors: Rao Sonu Kumar , Nishchal Naveen K.
Published: August 2024

Vector beam is a type of beam that has inhomogeneous polarization distribution across the transverse plane. In this study, an arbitrary vector light beam is used for asymmetric color image encryption achieving high level of security.
Historical Development of Coded Aperture Correlation Holography: Keynote Address
Authors: Anand Vijayakumar , Rosen Joseph
Published: August 2024

Coded aperture correlation holography (COACH) was developed in 2016 by connecting two research areas: coded aperture imaging and incoherent digital holography. Here, we review the history and recent developments of COACH beyond the state of the art.
Full-color complex hologram quality enhancement method captured with incoherent holographic camera
Authors: Choi Kihong , Hong Keehoon
Published: August 2024

This study enhances incoherent digital holography image quality using a U-Net-based network, addressing low dynamic range and noise issues. The result demonstrates significant improvement in image quality compared to the original data.
Parallel phase-shifting digital holography with a DMD using the fractional Talbot effect
Authors: Ipus Erick , Martínez-León Lluis , Lancis Jesús , Tajahuerce Enrique
Published: August 2024

We propose a parallel phase-shifting digital holography method using the fractional Talbot effect generated by periodic patterns encoded in a DMD. The method improves the efficiency of other phase-shifting holographic techniques based on DMDs.
Comparison of Monge-Ampère equation and Poisson’s equation for holographic lighting
Authors: Metzner Dominik , Hiller Lukas T.
Published: August 2024

Innovative lighting is an important part in lighting industry to improve safeness and visibility for example in road traffic. Developing lighting systems over the last decades, lighting systems were designed using halogen lamps to LED systems in the present. Modern lighting systems make use of holography. However, in many cases the light source is a fully coherent Laser beam that give us a precise reconstruction of the desired light distribution. In cases where the light source is a non-coherent LED, the accuracy reduces if we consider a holographic phase image created with the Gerchberg-Saxton algorithm started using a randomized initial phase. To improve the reconstruction using LEDs, we introduce two mathematical problems that could build the base for holographic lighting.
Volumetric micro clouds drawn with femtosecond laser pulses
Authors: Numazawa Keisuke , Kumagai Kota , Hayasaki Yoshio
Published: August 2024

Volumetric display with a micro cloud is developed. The micro cloud is generated with a focused laser pulse. The image is visualized by light scattering form the cloud voxels.
HoloTile for Volumetric Additive Manufacturing
Authors: Glückstad Jesper , Madsen Andreas Erik Gejl
Published: August 2024

HoloTile [1, 2, 3, 4] is a novel digital holographic light sculpting modality with properties well suited to volumetric additive manufacturing (VAM). This paper discusses the consequences of moving from an imaging-based to a holographic-based VAM configuration, and how HoloTile may be used to improve volumetric printing further.
Lorentz algebraic approach in two- and three-dimensional polarization optics
Authors: Wang Luo , Zhang Haiyang , Zhao Changming , He Jianwei
Published: August 2024

Lorentz algebra is a significant and elegant language in 2-D SAM-related polarization optics, and it also holds potential theoretical value in 3-D polarization optics. This paper focuses on developing a decomposed generalized Mueller matrix (GMM) model for 3-D polarization transformations through a Lorentz algebraic approach. We first present a comprehensive analysis and review of the 2-D polarization state (SoP) and polarization transformations, introducing the necessary algebraic representations and approaches. Then, we further develop the 3-D transformation theory and present a convenient decomposed 3-D transformation model, which exists in both generalized Jones matrices (GJMs) and GMM representations. For GMM, the generator matrices of all sub-transformations (r→-rotation, z→-rotation, and z→-boost) are clearly defined and discussed for the first time, to our knowledge. And their correctness is verified from commutative relations and GMM simulations. Additionally, another simulation is presented to illustrate the potential application of decomposed GMM in non-paraxial beams and polarized ray-optics.
Microwave photonics demodulation based on a fiber loop and a virtual Fabry-Perot interferometer for sapphire fiber temperature sensors
Authors: Li Rui , Chen Yuru , Lei Xiaohua , Lv Shaojie , Zhang Peng , Liu Xianming
Published: August 2024

The interferometric optical path difference (OPD) induced by changes in the measurand within the microwave band is comparatively smaller than that observed in the realm of lightwave, thereby leading to diminished sensitivity in sapphire fiber Fabry-Perot interferometers (FPIs) within the microwave band. In order to enhance sensitivity, we propose a microwave photonics sensing system predicated on a fiber loop and a virtual FPI. By employing a constructed fiber loop, the propagation path length of the modulated signal can be extended with an increase in the number of loops. The correlation between the number of loops and sensitivities is examined both theoretically and experimentally. Our findings illustrate a direct relationship between sensitivity and the number of loops, demonstrating an increment sensitivity with each additional loop. Specifically, the FPI frequency domain temperature sensitivity in the 5th loop measures approximately 4652.95 kHz/°C, marking an enhancement of around 9.24 times compared to the 1st loop.
Investigation of -1st-order diffraction in conditions between thin and thick holograms
Authors: Sun Chi , Lin Wen Kai , Lin Shiuan-Huei , Chen Chih-Hong , Cheng Chih-Yuan , Lin Chung-Kuan , Yu Yeh-Wei , Su Wei-Chia , Yang Tsung-Hsun , Sun Ching-Cherng
Published: August 2024

This paper explores the diffraction region between thin and thick holograms, commonly referred to as the transition region. The VOHIL model is used to assess the internal interference conditions along a specified diffraction direction. We examine the maximum phase difference between the two endpoints of the hologram for both the +1st-order and -1st-order diffractions through internal interference. This analysis leads to a criterion that aligns with the Klein parameter. Additionally, a new parameter, the de-phase factor, is introduced to assess the feasibility of diffraction along a chosen direction from a whole-field perspective. The variation of the de-phase factor in the -1st-order diffraction is slower compared to other directions, except for the +1st-order diffraction, owing to the natural existence of the -1st-order diffraction at every tiny hologram unit. The primary way to stop the -1st-order diffraction is by adjusting the thickness if the incident angle is fixed. Thus, examining the -1st-order diffraction is an effective way to check if a hologram is under the Bragg condition. Although rigorous simulation methods, such as rigorous coupled-wave analysis, can provide more precise results, the proposed analysis scheme, based on the VOHIL model, offers valuable physical insights into these characteristics.
High-precision DSM-based laser ranging method integrated with free space optical communication
Authors: Ao Xueyuan , Fan Qirun , Wang Yizhou , Zou Yang , Zou Yansheng , Dai Xiaoxiao , Liu Chen , Yang Qi , Liu Deming
Published: August 2024

Free space optical communication (FSOC) technology has been developed rapidly and practically applied in many scenarios such as satellite-related ones, in unmanned aerial vehicles, for underwater use, etc. In certain applications, it is very important to obtain the high-precision position and distance information. The laser ranging technology is one of the main ways to realize it. Moreover, it would be more interesting to accomplish the laser ranging integrated with the FSOC, which can effectively control the size, weight, and power of the FSOC terminals. However, in existing integrated laser communication and ranging solutions, the ranging accuracy is in the millimeter-level. To further improve the accuracy of laser ranging and communication rate in the integrated architecture, we propose a harmonic phase ranging method combined with delta-sigma modulation (DSM) based on a 10 Gb/s coherent FSOC. Through the DSM technology, a harmonic is converted into a digital signal which can be simply combined with the communication data and transmitted together in the FSO link. The laser ranging can thus be effectively combined with FSOC to realize an integrated architecture. Finally, the root means square error of the laser ranging are improved to ∼0.303 mm. Compared with the existing solutions, our proposed scheme shows both advantages of higher-precision ranging and higher communication rate.
Nonlinear integrated optical resonators for optical fibre data recovery
Authors: Boikov Ivan K. , Brunner Daniel , De Rossi Alfredo
Published: August 2024

We apply in simulation a reservoir computer based on evanescently coupled GaAs microrings for real-time compensation of a nonlinear distortion of a 50 Gbaud 16-QAM signal with the launch power up to 14 dBm in a standard single-mode optical fibre. We clearly evidence the crucial role of fast nonlinear response in enabling all-optical signal recovery in real time. With our system we are able to recover from linear and nonlinear distortion caused by a 20 km fibre and 12 dBm launch power below the forward error correction limit.
Diameter-dependent whispering gallery mode lasing effects in quantum dot micropillar cavities
Authors: Limame Imad , Shih Ching-Wen , Koulas-Simos Aris , Pietsch Johannes , Roche Léo J. , Plattner Moritz , Koltchanov Alexej , Rodt Sven , Reitzenstein Stephan
Published: August 2024

Whispering gallery mode (WGM) based microlasers have gained significant interest across various fields of nanophotonics, including biosensing, metrology, and on-chip excitation of single quantum dots in integrated quantum photonic structures. In this study, we report a comprehensive diameter-dependent study of whispering gallery mode lasing in quantum dot micropillar cavities. The lasing threshold, mode energy, quality factor, light-matter interaction in terms of the Purcell factor, and the free spectral range, are studied systematically for diameters ranging from 1 to 20 µm at cryogenic temperatures. To describe the experimental data, we use rate equation fitting and numerical simulations based on the finite element method, including realistic loss channels. Our results show a strong and systematic dependence of all lasing properties on the diameter of the micropillars. We also observe significant variations in the lasing properties of nominally identical micropillars, indicating a significant influence of the growth and fabrication imperfections on the output of the devices. The study provides important information on the optical properties of micropillar-based WGM lasing, which can aid in the advancement of optoelectronic applications using these nanophotonic structures.
Reflective angle-insensitive structural colors with a wide color gamut employing a Ni/ Ge2Sb2Te5 bilayer broadband absorber
Authors: Duan Zhenzhen , Chen Weijie , He Zexiang , Yang Jian , Cai Guangshi , Wang Haotong , Wang Ning , Hu Zexiong , Wang Dan , Chen Nan , Bu Yikun
Published: August 2024

A novel approach is proposed for generating reflective angle-insensitive structural colors with high purity, high brightness, and a wide color gamut in an asymmetric Fabry-Perot structure based on an ultra-thin bilayer absorber composed of Ni and Ge2Sb2Te5. The bilayer absorber is designed to have broadband absorption, enhancing the optical absorption across the entire visible spectrum and suppressing the reflection of complementary colors, thereby improving the color purity of reflective colors. By constructing a simplified five-layer structure and controlling only the thickness of the oxide layers, different colors can be achieved while maintaining high levels for all colors. The prepared structural color devices (yellow, cyan, magenta, green, blue, and purple) demonstrate exceptional angle-robust appearance within an incident light range of 0°–60° with reflection peaks exceeding 80%, as demonstrated theoretically and experimentally. This device offers a simple yet effective structure that utilizes a novel material combination and enables cost-effective mass production through just one coating run process. It holds significant potential for diverse applications in micro-nano displays, anti-counterfeiting, color filters, printing, illumination systems, and decorations.
Real-time optical fibre near-infrared chromatic dispersion analyser using collocated optical fibre gratings
Authors: Allsop Thomas , Ioannou Andreas , Kalli Kyriacos , Bhamber Ranjeet S. , Aguera Evelyne , Samson Alain , Rigou Peggy , Saucier Cedric , Dussardier Bernard
Published: August 2024

We present what we believe to be a novel optical fibre device for real-time measurements of near-infrared chromatic dispersion of a liquid medium from 1100 nm to 1700 nm. This inline optical fibre chromatic dispersion analyser is based upon collocated fibre long-period gratings written adjacently in the core by femtosecond laser inscription yielding 8 attenuation bands associated with different cladding modes, yielding 8 independent measurements. This fibre device is tested on a series of chemical compounds associated with wines. The results for each compound yielded distinctive chromatic responses. A machine learning pipeline was developed that successfully clustered and classified spectral responses of the different chemicals to illustrate the distinctive responses. The limits of detection for these fibre devices ranged from 1×10−3 to 6×10−5 mol/L for the compounds associated with wines, demonstrating the potential usefulness of an optical fibre chromatic dispersion analyser is capable of monitoring in real-time effective chromatic dispersion that is not offered by any current technology.
DMEDH: diffusion model-boosted multiplane extrapolation for digital holographic reconstruction
Authors: Gao Songyang , Xu Weisheng , Wu Xinyi , Liu Jiawei , Wang Bofei , Wu Tianya , Wan Wenbo , Liu Qiegen
Published: August 2024

Digital holography can reconstruct the amplitude and phase information of the target light field. However, the reconstruction quality is largely limited by the size of the hologram. Multi-plane holograms can impose constraints for reconstruction, yet the quality of the reconstructed images continues to be restricted owing to the deficiency of effective prior information constraints. To attain high-quality image reconstruction, a diffusion model-boosted multiplane extrapolation for digital holographic reconstruction (DMEDH) algorithm is proposed. The dual-channel prior information of amplitude and phase extracted through denoising score matching is employed to constrain the physically driven dual-domain rotational iterative process. Depending on the utilization of multi-plane hologram data, the serial DMEDH and the parallel DMEDH are presented. Compared with traditional methods, simulative and experimental results demonstrate that images reconstructed using DMEDH exhibit better reconstruction quality and have higher structural similarity, peak signal-to-noise ratios, and strong generalization. The reconstructed image using DMEDH from two holograms exhibits better quality than that of traditional methods from five holograms.
Enhanced axial strain and vector magnetic field sensitivity in MZI utilizing dual cascaded air bubbles with tapered fiber
Authors: Dong Changli , Liu Changning , Mo Huilin , Su Xiang , Chen Yilin , Cao Jianheng , Li Fan , Sun Simei , Jiang Chao
Published: August 2024

In this study, we believe this is a novel and compact fiber optic sensor for measuring strain and vector magnetic fields that has been proposed and examined. The sensor is comprised of a sequence of two bubbles and a tapered fiber with a diameter of 31µm, offering a maximum strain sensitivity of -44.5 pm/µɛ. A susceptible magnetic field sensing structure can be achieved by simply bonding the strain device to a magnetostrictive material. Results demonstrate that the sensor exhibits a magnetic field sensitivity of -0.7838 nm/mT, with a linear fit of 0.9931 within the 8 to 28 mT. The direction sensitivity is calculated to be 230.85 pm/° for a magnetic field of 24 mT. This work demonstrates the device's great mechanical strength, low cross-sensitivity to temperature, ease of manufacture, and versatility in measuring strain and vector magnetic fields, making it suitable for use in civil engineering, aerospace, and other industrial fields.
Parallel beam splitting based on gradient metasurface: from classical to quantum
Authors: Liu Qi , Liu Xuan , Tian Yu , Tian Zhaohua , Li Guixin , Ren Xi-Feng , Gong Qihuang , Gu Ying
Published: August 2024

Gradient metasurfaces are extensively utilized for polarized beam splitting (BS) in classical and quantum optics. Specifically, their phase gradient allows the path and polarization of multiple output lights to be locked by corresponding inputs. However, the full potential of this unique path-polarization-locked property in multi-beam splitting has not been investigated. Here, we demonstrate that a single metasurface can function as sequentially linked beam splitters, enabling the parallelization of a series of BS processes, which provides a multi-beam interference capability. In the classical region, we demonstrate that parallel BS allows continuous modulation of output light intensity and polarization state through input polarization adjustment. While in the quantum realm, parallel BS introduces an additional path-polarization correlation into Hong–Ou–Mandel interference for orthogonal circularly polarized photons. The principle of parallel BS through the metasurface presents a versatile approach to manipulate light at the micro-scale, which will have potential applications in optical computing and on-chip quantum information processing.
Polarized, broadly tunable, 2.3 µm continuous-wave laser operation of Tm3+-vanadate crystals
Authors: Yu Xiaoxu , Pan Zhongben , Pan Han , Chu Hongwei , Li Dechun
Published: August 2024

We report for the first time the polarized, broadly tunable, continuous-wave laser operation on the 3H4 → 3H5 transition in Tm3+-vanadate (Tm:REVO4, RE = Gd, Y, Lu) crystals. Continuous wavelength tunings with tuning widths of about 200 nm were achieved in π-polarization for both the Tm:GdVO4 and Tm:YVO4 crystals. To the best of our knowledge, these tuning widths are broader than most previously reported values for wavelength tunable 2.3 µm Tm lasers. Especially for σ-polarization, all the Tm:REVO4 lasers provide very smooth wavelength tuning curves around 2.3 µm. This work demonstrates the excellent broad wavelength tunability of the Tm:REVO4 crystals and their great potential for supporting the generation of ultrashort pulses from mode-locked lasers.
Solid and hollow plasmonic nanoresonators for carrier envelope phase read-out
Authors: Szenes András , Vass Dávid , Bánhelyi Balázs , Földi Péter , Csete Mária
Published: August 2024

The geometry of gold plasmonic nanoantennae was numerically optimized to maximize their sensitivity to the carrier envelope phase (CEP) of the exciting ultra-short laser pulses. Three structure types, triangular, teardrop-shaped and plasmonic lens, were optimized in solid and hollow compositions as well. Hollow / solid singlets results in the largest/intermediate CEP dependent (Q1) – to – CEP independent (Q0) integrated current components’ ratio, while their Q1 was the smallest / intermediate. The largest / intermediate Q12/Q0 CEP sensitivity was achieved via solid / hollow plasmonic lenses due to their large near-field enhancement and Q1, while the Q1/Q0 ratio was smaller than for counterpart singlets.
Molecular dynamics simulations reveal how vinculin refolds partially unfolded talin rod helices to stabilize them against mechanical force
Authors: Mykuliak Vasyl V. , Rahikainen Rolle , Ball Neil J. , Bussi Giovanni , Goult Benjamin T. , Hytönen Vesa P.
Published: August 2024

Vinculin binds to specific sites of mechanically unfolded talin rod domains to reinforce the coupling of the cell’s exterior to its force generation machinery. Force-dependent vinculin–talin complexation and dissociation was previously observed as contraction or extension of the unfolded talin domains respectively using magnetic tweezers. However, the structural mechanism underlying vinculin recognition of unfolded vinculin binding sites (VBSs) in talin remains unknown. Using molecular dynamics simulations, we demonstrate that a VBS dynamically refolds under force, and that vinculin can recognize and bind to partially unfolded VBS states. Vinculin binding enables refolding of the mechanically strained VBS and stabilizes its folded α-helical conformation, providing resistance against mechanical stress. Together, these results provide an understanding of a recognition mechanism of proteins unfolded by force and insight into the initial moments of how vinculin binds unfolded talin rod domains during the assembly of this mechanosensing meshwork.
Impact of rice GENERAL REGULATORY FACTOR14h (GF14h) on low-temperature seed germination and its application to breeding
Authors: Sugimura Yusaku , Oikawa Kaori , Sugihara Yu , Utsushi Hiroe , Kanzaki Eiko , Ito Kazue , Ogasawara Yumiko , Fujioka Tomoaki , Takagi Hiroki , Shimizu Motoki , Shimono Hiroyuki , Terauchi Ryohei , Abe Akira
Published: August 2024

Direct seeding is employed to circumvent the labor-intensive process of rice (Oryza sativa) transplantation, but this approach requires varieties with vigorous low-temperature germination (LTG) when sown in cold climates. To investigate the genetic basis of LTG, we identified the quantitative trait locus (QTL) qLTG11 from rice variety Arroz da Terra, which shows rapid seed germination at lower temperatures, using QTL-seq. We delineated the candidate region to a 52-kb interval containing GENERAL REGULATORY FACTOR14h (GF14h) gene, which is expressed during seed germination. The Arroz da Terra GF14h allele encodes functional GF14h, whereas Japanese rice variety Hitomebore harbors a 4-bp deletion in the coding region. Knocking out functional GF14h in a near-isogenic line (NIL) carrying the Arroz da Terra allele decreased LTG, whereas overexpressing functional GF14h in Hitomebore increased LTG, indicating that GF14h is the causal gene behind qLTG11. Analysis of numerous Japanese rice accessions revealed that the functional GF14h allele was lost from popular varieties during modern breeding. We generated a NIL in the Hitomebore background carrying a 172-kb genomic fragment from Arroz da Terra including GF14h. The NIL showed superior LTG compared to Hitomebore, with otherwise comparable agronomic traits. The functional GF14h allele from Arroz da Terra represents a valuable resource for direct seeding in cold regions.
The epidemiology and risk factors for postnatal complications among postpartum women and newborns in southwestern Uganda: A prospective cohort study
Authors: Pillay Yashodani , Ngonzi Joseph , Nguyen Vuong , Payne Beth A. , Komugisha Clare , Twinomujuni Annet Happy , Vidler Marianne , Lavoie Pascal M. , Bebell Lisa M. , Christoffersen-Deb Astrid , Kenya-Mugisha Nathan , Kissoon Niranjan , Ansermino J. Mark , Wiens Matthew O.
Published: August 2024

Sub-Saharan Africa accounts for two-thirds of the global burden of maternal and newborn deaths. Adverse outcomes among postpartum women and newborns occurring in the first six weeks of life are often related, though data co-examining patients are limited. This study is an exploratory analysis describing the epidemiology of postnatal complications among postpartum women and newborns following facility birth and discharge in Mbarara, Uganda. This single-site prospective cohort observational study enrolled postpartum women following facility-based delivery. To capture health information about both the postpartum women and newborns, data was collected and categorized according to domains within the continuum of care including (1) social and demographic, (2) pregnancy history and antenatal care, (3) delivery, (4) maternal discharge, and (5) newborn discharge. The primary outcomes were readmission and mortality within the six-week postnatal period as defined by the WHO. Multivariable logistic regression was used to identify risk factors. Among 2930 discharged dyads, 2.8% and 9.0% of women and newborns received three or more postnatal visits respectively. Readmission and deaths occurred among 108(3.6%) and 25(0.8%) newborns and in 80(2.7%) and 0(0%) women, respectively. Readmissions were related to sepsis/infection in 70(88%) women and 68(63%) newborns. Adjusted analysis found that caesarean delivery (OR:2.91; 95%CI:1.5–6.04), longer travel time to the facility (OR:1.54; 95%CI:1.24–1.91) and higher maternal heart rate at discharge (OR:1.02; 95%CI:1.00–1.01) were significantly associated with maternal readmission. Discharge taken on all patients including maternal haemoglobin (per g/dL) (OR:0.90; 95%CI:0.82–0.99), maternal symptoms (OR:1.76; 95%CI:1.02–2.91), newborn temperature (OR:1.66; 95%CI:1.28–2.13) and newborn heart rate at (OR:1.94; 95%CI:1.19–3.09) were risk factors among newborns. Readmission and death following delivery and discharge from healthcare facilities is still a problem in settings with low rates of postnatal care visits for both women and newborns. Strategies to identify vulnerable dyads and provide better access to follow-up care, are urgently required.
Could a ring treatment approach be proposed to control Taenia solium transmission in a post elimination setting? A pilot study in Zambia
Authors: Trevisan Chiara , Mwape Kabemba E. , Van Damme Inge , Saelens Ganna , Mubanga Chishimba , Chembensofu Mwelwa , Masuku Maxwell , O’Neal Seth , Zulu Gideon , Dorny Pierre , Gabriël Sarah
Published: August 2024

Background

Geographically targeted Taenia solium ring approaches consisting of treating individuals within a radius of 100-meter of a cysticercosis positive pig have been trialled in Peru. This study explored if a similar approach could be proposed to control T. solium transmission in a post elimination setting in Zambia, focussing on community members’ willingness to be sampled and treated.

Methodology and Principal findings

The study was conducted in a community where elimination of active T. solium transmission was achieved. All eligible pigs and people were sampled, at 4- to 6-monthly intervals, followed by implementation of the ring treatment approach. This implied that whenever a pig was seropositive for cysticercosis during sampling, every human and pig residing in a radius of 50-meters of the seropositive pig would be treated. The results of the positive human stool samples were used to create the rings, whenever no pigs were positive.

From June 2018 to October 2019, four samplings, followed by ring treatments were conducted. Between 84% and 91% of the willing people provided a stool sample, covering 46% to 59% of the total population living in the study area. Between 78% and 100% of the eligible pigs got sampled. Three ring treatments were based on porcine seropositivity and one on taeniosis results. Two to four rings were opened per sampling. During the ring treatments, between 89% and 100% of the eligible human and pig population living within a ring was treated.

Conclusions

Participants were willing to participate and get treatment, once the rings were opened. However, the utility of ring treatment approaches in a post elimination setting needs further evaluation, given the lack of highly accurate diagnostic tools for porcine cysticercosis and the challenges in obtaining stool samples. The ring treatment approach adopted should be further improved before recommendations to public health authorities can be given.
Association between geniquin therapy and the risk of developing periodontal disease in patients with primary Sjögren’s syndrome: A population-based cohort study from Taiwan
Authors: Chiu Chun-Yuan , Yuh Da-Yo , Yeh Li-Chyun , Lin Iau-Jin , Chung Chi-Hsiang , Li Chung-Hsing , Chien Wu-Chien , Chen Gunng-Shinng
Published: August 2024

Primary Sjögren’s syndrome (pSS) is a chronic autoimmune disease that causes dysfunction of salivation and harmful oral conditions. The association between periodontal disease (PD) and pSS with or without geniquin therapy remains controversial. This study evaluated the association between geniquin therapy and the risk of subsequent development of PD in pSS patients. From Taiwan’s National Health Insurance Research Database, we selected a control cohort of 106,818 pSS patients, followed up from 2000 to 2015, matched (1:4) by age and index year with 427,272 non-pSS patients. We also analyzed 15,149 pSS patients receiving geniquin therapy (cohort 1) and 91,669 pSS patients not receiving geniquin therapy (cohort 2). After adjusting for confounding factors, multivariate Cox proportional hazards regression analysis was used to compare the risk of PD over the 15-year follow-up. In the control cohort, 11,941 (11.2%) pSS patients developed PD compared to 39,797 (9.3%) non-pSS patients. In cohorts 1 and 2, 1,914 (12.6%) pSS patients receiving geniquin therapy and 10,027 (10.9%) pSS patients not receiving geniquin therapy developed PD. The adjusted hazard ratio (HR) for subsequent PD in pSS patients was 1.165 (95% confidence interval [CI] = 1.147–1.195, p < 0.001) and in pSS patients receiving geniquin therapy was 1.608 (95% CI = 1.526–1.702, p < 0.001). The adjusted HR for PD treatment was 1.843. Patients diagnosed with pSS showed an increased risk of developing subsequent PD and receiving PD treatment than patients without pSS, while pSS patients receiving geniquin therapy showed even higher risks.
Microevolutionary hypothesis of the obesity epidemic
Authors: Fraiman Joseph , Baver Scott , Henneberg Maciej
Published: August 2024

The obesity epidemic represents potentially the largest phenotypic change in Homo sapiens since the origin of the species. Despite obesity’s high heritability, it is generally presumed a change in the gene pool could not have caused the obesity epidemic. Here we advance the hypothesis that a rapid change in the obesogenic gene pool has occurred second to the introduction of modern obstetrics dramatically altering evolutionary pressures on obesity—the microevolutionary hypothesis of the obesity epidemic. Obesity is known to increase childbirth-related mortality several fold. Prior to modern obstetrics, childbirth-related mortality occurred in over 10% of women in their lifetime. After modern obstetrics, this mortality reduced to a fraction of a percent, thereby lifting a strong negative selection pressure. Regression analysis of data for ~ 190 countries was carried out to examine associations between 1990 lifetime maternal death rates (LMDR) and current obesity rates. Multivariate regression showed LMDR correlated more strongly with national obesity rates than GDP, calorie intake and physical inactivity. Analyses controlling for confounders via partial correlation show that LMDR explains approximately 11% of the variability of obesity rate between nations. For nations with LMDR above the median (>0.45%), LMDR explains 33% of obesity variance, while calorie intake, GDP and physical inactivity show no association with obesity in these nations. The microevolutionary hypothesis offers a parsimonious explanation of the global nature of the obesity epidemic.
Lightweight cattle pose estimation with fusion of reparameterization and an attention mechanism
Authors: Zhao Enming , Chen Bobo , Zhao Hongyi , Liu Guangyu , Jiang Jianbo , Li Yanpeng , Zhang Jilei , Luo Chuang
Published: August 2024

Heatmap-based cattle pose estimation methods suffer from high network complexity and low detection speed. Addressing the issue of cattle pose estimation for complex scenarios without heatmaps, an end-to-end, lightweight cattle pose estimation network utilizing a reparameterized network and an attention mechanism is proposed to improve the overall network performance. The EfficientRepBiPAN (Efficient Representation Bi-Directional Progressive Attention Network) module, incorporated into the neck network, adeptly captures target features across various scales while also mitigating model redundancy. Moreover, a 3D parameterless SimAM (Similarity-based Attention Mechanism) attention mechanism is introduced into the backbone to capture richer directional and positional feature information. We constructed 6846 images to evaluate the performance of the model. The experimental results demonstrate that the proposed network outperforms the baseline method with a 4.3% increase in average accuracy at OKS = 0.5 on the test set. The proposed network reduces the number of floating-point computations by 1.0 G and the number of parameters by 0.16 M. Through comparative evaluations with heatmap and regression-based models such as HRNet, HigherHRNet, DEKR, DEKRv2, and YOLOv5-pose, our method improves AP0.5 by at least 0.4%, reduces the number of parameters by at least 0.4%, and decreases the amount of computation by at least 1.0 GFLOPs, achieving a harmonious balance between accuracy and efficiency. This method can serve as a theoretical reference for estimating cattle poses in various livestock industries.
Exposure to fine particulate matter in the New York City subway system during home-work commute
Authors: Azad Shams , Ferrer-Cid Pau , Ghandehari Masoud
Published: August 2024

The New York City (NYC) subway system accommodates 5.5 million daily commuters, and the environment within the subway is known to have high concentrations of fine particulate matter (PM2.5) pollution. Naturally, subway air pollution varies among individuals according to their mobility patterns, introducing the possibility of inequality in PM2.5 exposure. This study aims to evaluate individual and community-level exposure to subway PM2.5. We simulated the intracity home-to-work trip patterns using the Longitudinal Employer-Household Dynamics (LEHD) records of 3.1 million working commuters across 34,169 census blocks in four boroughs (Manhattan, Brooklyn, Queens, and the Bronx) of NYC. We incorporated the on-platform and on-train measured PM2.5 concentration data for the entire subway system. The mean underground platform concentration in the city was 139 μg/m3 with a standard deviation of 25 μg/m3, while the on-train concentration when underground was 99 μg/m3 with a standard deviation of 21 μg/m3. Using a network model, we determined the exposure of individual commuters during their daily home-work trips. We quantified the mean per capita exposure at the census block level by considering the proportion of workers within the blocks who rely on the subway for their work commute. Results indicate statistically significant weak positive correlation between elevated subway PM2.5 exposure and economically disadvantaged and racial minority groups.
Affective Sensitivity to Air Pollution (ASAP): Person-specific associations between daily air pollution and affective states
Authors: Ng Michelle , Gerstorf Denis , Conroy David E. , Pincus Aaron L. , Ram Nilàm
Published: August 2024

Individuals’ sensitivity to climate hazards is a central component of their vulnerability to climate change. In this paper, we introduce and outline the utility of a new intraindividual variability construct, affective sensitivity to air pollution (ASAP)–defined as the extent to which an individual’s affective states fluctuate in accordance with daily changes in air quality. As such, ASAP pushes beyond examination of differences in individuals’ exposures to air pollution to examination of differences in individuals’ sensitivities to air pollution. Building on known associations between air pollution exposure and adverse mental health outcomes, we empirically illustrate how application of Bayesian multilevel models to intensive repeated measures data obtained in an experience sampling study (N = 150) over one year can be used to examine whether and how individuals’ daily affective states fluctuate with the daily concentrations of outdoor air pollution in their county. Results indicate construct viability, as we found substantial interindividual differences in ASAP for both affect arousal and affect valence. This suggests that repeated measures of individuals’ day-to-day affect provides a new way of measuring their sensitivity to climate change. In addition to contributing to discourse around climate vulnerability, the intraindividual variability construct and methodology proposed here can help better integrate affect and mental health in climate adaptation policies, plans, and programs.
Role of the polyamine transporter PotABCD during biofilm formation by Streptococcus pneumoniae
Authors: Vieira Brenda , Alcantara Jessica B. , Destro Giulia , Guerra Maria E. S. , Oliveira Sheila , Lima Carolina A. , Longato Giovanna B. , Hakansson Anders P. , Leite Luciana C. , Darrieux Michelle , R. Converso Thiago
Published: August 2024

Streptococcus pneumoniae is a bacterium of great global importance, responsible for more than one million deaths per year. This bacterium is commonly acquired in the first years of life and colonizes the upper respiratory tract asymptomatically by forming biofilms that persist for extended times in the nasopharynx. However, under conditions that alter the bacterial environment, such as viral infections, pneumococci can escape from the biofilm and invade other niches, causing local and systemic disease of varying severity. The polyamine transporter PotABCD is required for optimal survival of the organism in the host. Immunization of mice with recombinant PotD can reduce subsequent bacterial colonization. PotD has also been suggested to be involved in pneumococcal biofilm development. Therefore, in this study we aimed to elucidate the role of PotABCD and polyamines in pneumococcal biofilm formation. First, the formation of biofilms was evaluated in the presence of exogenous polyamines–the substrate transported by PotABCD–added to culture medium. Next, a potABCD-negative strain was used to determine biofilm formation in different model systems using diverse levels of complexity from abiotic surface to cell substrate to in vivo animal models and was compared with its wild-type strain. The results showed that adding more polyamines to the medium stimulated biofilm formation, suggesting a direct correlation between polyamines and biofilm formation. Also, deletion of potABCD operon impaired biofilm formation in all models tested. Interestingly, more differences between wild-type and mutant strains were observed in the more complex model, which emphasizes the significance of employing more physiological models in studying biofilm formation.
Investigating the closure stress and crack initiation stress in fractured rocks using the student t distribution and Monte Carlo simulation method
Authors: Lin Hanjie , Qiang Yue , Li Li , Li Hongjian , Liang Siyu
Published: August 2024

Traditional method of determining closure and initiation stress of fractured rocks by analyzing the stress-strain curve has problems such as strong subjectivity and large errors. This study utilized the rock closure stress values and onset stress values determined by three traditional methods, namely, axial strain method, fracture volume method and empirical value taking method, as the base database. The Student t distribution theory was used to obtain a confidence interval based on its overall distribution of values and to achieve a combination of the advantages of multiple methods. Within confidence interval, the Monte Carlo stochastic simulation was used to determine the convergence interval of the second stage to further improve the accuracy. Finally, mean value of the randomly sampled values after reaching the convergence stage was taken as the probability value of rock closure and crack initiation stress. The results showed that the 3 traditional methods for calculating rock closure and initiation stresses are significantly different. In contrast, the proposed method biases more towards multi-numerical distribution intervals and also considers the preference effects of different calculation methods. In addition, this method does not show any extreme values that deviate from the confidence intervals, and it has strong accuracy and stability compared to other methods.
Orchid species diversity across a forest disturbance gradient in west Mau forest, Kenya
Authors: N. Mirioba Job , Emitaro William , Obwanga Benson , Gaya Humphrey , Leley Nereoh , Otuoma John , M. Maina John , Kawaka Fanuel
Published: August 2024

Orchidaceae is one of the most diverse and widespread groups of flowering plants. Despite their immense ecological and socio-economic value, their spatial distribution across forest disturbance gradient is not well understood, particularly in tropical montane forests. This study assessed the influence of forest degradation on orchid species richness and abundance in West Mau Forest, Kenya. Stratified systematic sampling was adopted across three different disturbance regimes consisting of relatively intact forest, moderately disturbed forest and highly degraded forest. A total of five orchid species were recorded from nine host-tree species. The intact forest had seven host tree species with five orchid species. The moderately degraded forest had four host-tree species with two orchid species, while the highly degraded forest that had no orchids. Polystachya confusa was the most abundant orchid species (600.0±227.9 clumps ha-1) followed by Bulbophyllum sp (340.0±112.2 clumps ha-1), Chamaeangis sp (300.0±115.5 clumps ha-1), Aerangis sp (200.0±57.7 clumps ha-1) and Tridactyle sp (100.0±0.0 clumps ha-1). The results of this study indicate that forest degradation reduces orchid species diversity in tropical montane forests. They also show that orchids are bioindicators of forest degradation status.