bluuebunny/crossref_metadata_2025 huggingface dataset:
Learning from success cases: ecological analysis of pathways to universal access to family planning care in low- and middle-income countries.
Authors: Hellwig Franciele , Barros Aluisio JD
Published: October 2022

Background 

Universal access to family planning services is a well-recognized human right and several countries and organizations are committed to this goal. Our objective was to identify countries who improved family planning coverage in the last 40 years and investigate which contexts enabled those advances. 

Methods 

Analyses were based on data from publicly available national health surveys carried out since 1986 in Egypt, Ethiopia, Rwanda, Afghanistan, Brazil, and Ecuador, selected based on previous evidence. We estimated demand for family planning satisfied with modern methods (mDFPS) for each country and explored inequalities in terms of wealth, women’s education, and women’s age. We also explored contextual differences in terms of women’s empowerment, percentage of population living in extreme poverty, and share of each type of contraceptive. To better understand political and sociocultural contexts, country case studies were included, based on literature review. 

Results 

Patterns of mDFPS increase were distinct in the selected countries. Current level of mDFPS coverage ranged between 94% in Brazil and 38% in Afghanistan. All countries experienced important reduction in both gender inequality and extreme poverty. According to the share of each type of contraceptive, most countries presented higher use of short-acting reversible methods. Exceptions were Ecuador, where the most used method is sterilization, and Egypt, which presented higher use of long-acting reversible methods. In the first years analyzed, all countries presented huge gaps in coverage according to wealth, women’s education and women’s age. All countries managed to increase coverage over recent years, especially among women from the more vulnerable groups. 

Conclusions 

Family planning coverage increased along with reductions in poverty and gender inequality, with substantial increases in coverage among the most vulnerable in recent years. Policies involving primary health care services, provision of various methods, and high quality training of health providers are crucial to increase coverage.
Real-time quality control of optical backscattering data from Biogeochemical-Argo floats
Authors: Dall'Olmo Giorgio , Bhaskar TVS Udaya , Bittig Henry , Boss Emmanuel , Brewster Jodi , Claustre Hervé , Donnelly Matt , Maurer Tanya , Nicholson David , Paba Violetta , Plant Josh , Poteau Antoine , Sauzède Raphaëlle , Schallenberg Christina , Schmechtig Catherine , Schmid Claudia , Xing Xiaogang
Published: October 2022

Background: Biogeochemical-Argo floats are collecting an unprecedented number of profiles of optical backscattering measurements in the global ocean. Backscattering (BBP) data are crucial to understanding ocean particle dynamics and the biological carbon pump. Yet, so far, no procedures have been agreed upon to quality control BBP data in real time.

Methods: Here, we present a new suite of real-time quality-control tests and apply them to the current global BBP Argo dataset. The tests were developed by expert BBP users and Argo data managers and have been implemented on a snapshot of the entire Argo dataset.

Results: The new tests are able to automatically flag most of the “bad” BBP profiles from the raw dataset.

Conclusions: The proposed tests have been approved by the Biogeochemical-Argo Data Management Team and will be implemented by the Argo Data Assembly Centres to deliver real-time quality-controlled profiles of optical backscattering. Provided they reach a pressure of about 1000 dbar, these tests could also be applied to BBP profiles collected by other platforms.
The impact of COVID-19 on the Persian Gulf: the realist perspective
Authors: Grabowski Wojciech
Published: October 2022

This article aims to show the impact of the coronavirus disease 2019 (COVID-19) pandemic on international relations and state policy in the Persian Gulf through the prism of realism theory. COVID-19 became a game changer for the domestic politics of the Persian Gulf countries and for the balance of power in that subregion. The application of realism reveals the statecraft of the Arab Persian Gulf during the pandemic to be a struggle for power and its consolidation. Therefore the hypothesis of the article holds that the authoritarian Arab Gulf states used the global COVID-19 pandemic crisis to consolidate and strengthen regime power and conduct humanitarian/mask/COVID-19 diplomacy toward the regimes most affected by the pandemic, shifting the geopolitical landscape. The first part of the article presents the general assumption of the analysis and the theoretical framework. The second and the third respectively discuss domestic and foreign policies of the Arab Persian Gulf states in the face of the pandemic, highlighting strengthening authoritarian tendencies and authoritarian bilateral cooperation. The fourth part relate to the Gulf Cooperation Council and its reaction on COVID-19. The last part draws on the theoretical framework adopted in the article offer conclusions that answer research questions.
Public Policy and Broader Applications for the Use of Text Analytics During Pandemics
Authors: Bumblauskas Dan , Igou Amy , Kalghatgi Salil , Wetzel Cole
Published: October 2022

The state of Iowa conducted an initial business survey in March 2020 as the novel coronavirus disease 2019 (COVID-19) broke out across the United States. The survey data have been used for decision and policy making at the state level. Relief incentive packages were provided via the Iowa Economic Development Authority (IEDA) to Iowa-based companies to support their operations. A team of policy makers, faculty, and industry professionals was formed to conduct text analyses, analyze the survey responses, validate insights, and ensure that the appropriate policies were enacted. The analysis yielded a reproducible process using the statistical software R to quickly analyze large volumes of free-text responses to open-ended survey questions and develop topics comparable to those found through human coding. This process, using biterm topic models (BTMs), was first used to verify and validate the results of human coding and, because of its increased speed to insights compared with that of human coding, to validate hypotheses empirically much more quickly in subsequent surveys. Analyzing free-text responses has given the IEDA confidence that open-ended survey questions provide value not previously captured. In addition to the original survey, the three subsequent ones, along with several additional projects, have been shaped by the original text-mining methods.

History: This paper was refereed. This article has been selected for inclusion in the Special Issue on Analytics Remedies to COVID-19.
Burocracia e orçamento: como atores políticos usam regras institucionais para alterar o orçamento municipal em São Paulo
Authors: de Godoy Samuel Ralize , Peres Ursula Dias
Published: October 2022

O presente capítulo apresenta resultados parciais de uma pesquisa em andamento sobre a atuação da burocracia na execução orçamentária municipal.
ACP-supported redeployment in response to the COVID-19 pandemic: a service evaluation of staff experience
Authors: Scott Paul Anthony , Orton Helen , Daw Rachael
Published: October 2022

Background:

During the COVID-19 pandemic, healthcare organisations around the world had to optimise resources and redeploy staff to meet unprecedented demands on services. This service evaluation aims to establish the experiences of nurses redeployed to a COVID-negative Nightingale ward during the first wave of the pandemic in the UK.

Methods:

Purposive sampling using a survey was used to capture nurses' experiences. Data were extrapolated to meet the aims of the thematic line of enquiry and descriptive statistics used to analyse the data set.

Results:

The response rate was 34.0% (n=30). The majority of redeployees (76.7%; n=23) strongly agreed or agreed the trust induction had been beneficial. Informal learning, including from colleagues, was said to be very helpful by 50.0% (n=15) and helpful by 36.7% (n=10) of participants. Most (90.0%; n=27) agreed they were able to maintain safety, with 93.3% (n=28) satisfied with the quality of their care. Regarding giving the care they aspired to, 46.7% (n=14) strongly agreed and 40.0% (n=12) agreed they had been able to do this.

Conclusion:

The advanced clinical practitioner role was central to successful redeployment, in preparing redeployees through induction and education. These practitioners facilitated the acquisition of the knowledge and skills to deliver competent care, ensuring staff had the capacity and capability to undertake their job. Patient safety was not compromised by redeployment.
Learning beyond a single field of nursing through a virtual case-based approach to pre-registration nurse education
Authors: Roberts Christine , Morrell-Scott Nicola , Wilkinson Amy
Published: October 2022

Ensuring that pre-registration student nurses gain the richness of clinical practice to allow them to feel confident and knowledgeable to care for patients of the 21st century is often a challenge. Clinical practice challenges often mean that students will be strategic learners. This article discusses the development of a virtual case-based learning site to provide a rich experience for students to learn.
Overactive bladder: not just a normal part of getting older
Authors: Carpenter Lucy , Campain Nicholas J
Published: October 2022

Overactive bladder (OAB) is a common yet under-reported condition affecting both men and women. Prevalence rises with age, but OAB can affect people of any age. It is associated with increased physical and mental health problems and may lead to social isolation and escalating care needs. It is a clinical diagnosis with symptoms of urgency, with or without urge incontinence and usually with urinary frequency and nocturia. Management includes conservative, medical and surgical treatments, which can significantly improve quality of life. This review aims to raise awareness of this under-reported condition and to empower health professionals to open discussions on bladder health with all those in their care.
Recyclable structural parts for sustainable construction
Authors: García Sergio Navarro
Published: October 2022

Plastics technology center AIMPLAS is researching how to make 100% recyclable structural composite parts more quickly and cost-effectively to help the combustion industry meet its carbon emission goals.
Unconventional membranes for direct air carbon capture
Authors: Gobina Edward , Giwa Ayo , Ben-Aron Adam
Published: October 2022

Carbon capture and storage provide a way of mitigating carbon dioxide emissions whilst enabling the continued use of fossil fuels during the period of energy transition leading to net zero emissions. This article describes research that is being done in Scotland, UK, at Robert Gordon University, that is pioneering the use of unconventional membranes for direct air carbon capture. The project, run in collaboration with two Canadian companies, aims to deliver a simple, easily deployable, mechanically stable, continuous and sustainable technology to capture carbon dioxide directly from air.
Importance of posterior tibial slope in joint kinematics with an anterior cruciate ligament-deficient knee
Authors: Shu Liming , Abe Nobuhiro , Li Shihao , Sugita Naohiko
Published: October 2022

Aims

To fully quantify the effect of posterior tibial slope (PTS) angles on joint kinematics and contact mechanics of intact and anterior cruciate ligament-deficient (ACLD) knees during the gait cycle.

Methods

In this controlled laboratory study, we developed an original multiscale subject-specific finite element musculoskeletal framework model and integrated it with the tibiofemoral and patellofemoral joints with high-fidelity joint motion representations, to investigate the effects of 2.5° increases in PTS angles on joint dynamics and contact mechanics during the gait cycle.

Results

The ACL tensile force in the intact knee was significantly affected with increasing PTS angle. Considerable differences were observed in kinematics and initial posterior femoral translation between the intact and ACLD joints as the PTS angles increased by more than 2.5° (beyond 11.4°). Additionally, a higher contact stress was detected in the peripheral posterior horn areas of the menisci with increasing PTS angle during the gait cycle. The maximum tensile force on the horn of the medial meniscus increased from 73.9 N to 172.4 N in the ACLD joint with increasing PTS angles.

Conclusion

Knee joint instability and larger loading on the medial meniscus were found on the ACLD knee even at a 2.5° increase in PTS angle (larger than 11.4°). Our biomechanical findings support recent clinical evidence of a high risk of failure of ACL reconstruction with steeper PTS and the necessity of ACL reconstruction, which would prevent meniscus tear and thus the development or progression of osteoarthritis. Cite this article: Bone Joint Res 2022;11(10):739–750.
Objective speckle pattern-based surface roughness measurement using matrix factorization
Authors: Patil Shanta Hardas , Kulkarni Rishikesh
Published: October 2022

A method for the measurement of profile parameters of both isotropic and anisotropic surfaces is presented using the objective laser speckle imaging technique. The surface parameters are characterized in terms of a singular value decomposition method-based metric derived from the initial key contributing singular values of the speckle pattern. A simulation study is performed with random Gaussian anisotropic surfaces generated as a function of the correlation lengths in both

x

and

y

directions. In the experimental demonstration, the proposed method is verified with metallic samples having distinct surface roughness processed through widely used machining operations viz., vertical milling, and grinding. A brief discussion about the extent to which the minimum number of singular values that are sufficient to evaluate the profile parameters in the context of experimental results is provided. The method supports the measurement of profile parameters of higher magnitude in the realm of non-contact topographic measurement techniques. The experimental results substantiate the practical applicability of the proposed method.
Comparative study for evaluating the cost efficiency of 5G Ethernet mobile fronthaul networks
Authors: Kim Joonyoung , Chang Sun Hyok , Lee Joon Ki
Published: October 2022

With the advances in mobile network technologies, the fronthaul is being evolved to centralized and cloud networks, leading to the emergence of various optical multiplexing architectures. Among others, the Ethernet-based packet switching network is considered one of the most promising concepts due to the inherent merits of Ethernet such as backward compatibility, high reliability, and cost reduction. This work aims at evaluating the Ethernet-based mobile fronthaul network by comparing it with other configuration options. In particular, we calculate and compare the total cost of ownership (TCO) in order to emphasize the cost efficiency of the 5G Ethernet fronthaul network. For this, we analyze the packet aggregation capabilities of the Ethernet fronthaul through queueing latency modeling. Hence, we show that the statistical multiplexing enabled by packet switching reduces the cost related to optical transceiver modules and subsequently fiber optic cabling, which eventually allows for the TCO to be less than 70% of the active transparent system.
Deriving instrumental point spread functions from partially occulted images
Authors: Hofmeister Stefan J. , Hahn Michael , Wolf Savin Daniel
Published: October 2022

The point spread function (PSF) of an imaging system describes the
response of the system to a point source. Accurately determining the
PSF enables one to correct for the combined effects of focusing and
scattering within the imaging system and, thereby, enhance the spatial
resolution and dynamic contrast of the resulting images. We present a
semi-empirical semi-blind methodology to derive a PSF from partially
occulted images. We partition the two-dimensional PSF into multiple
segments, set up a multilinear system of equations, and directly fit
the system of equations to determine the PSF weight in each segment.
The algorithm is guaranteed to converge toward the correct
instrumental PSF for a large class of occultations, does not require a
predefined functional form of the PSF, and can be applied to a large
variety of partially occulted images, such as within laboratory
settings, regular calibrations within a production line or in the
field, astronomical images of distant clusters of stars, or partial
solar eclipse images. We show that the central weight of the PSF,
which gives the percentage of photons that are not scattered by the
instrument, is accurate to better than 1.2%. The mean absolute
percentage error between the reconstructed and true PSF is usually
between 0.5 and 5% for the entire PSF, between 0.5 and 5% for the PSF
core, and between 0.5 and 3% for the PSF tail.
All-optic control using a photo-thermal heater in Si photonics
Authors: Li Liucun , Tamanuki Takemasa , Baba Toshihiko
Published: October 2022

We propose and demonstrate a simple all-optic control for Si photonics using a photo-thermal heater. The control light is absorbed in a heavily doped control waveguide and the signal light phase is tuned through thermal diffusion in a signal waveguide adjacent to but not optically coupled with the control waveguide. We designed and fabricated Mach–Zehnder- and microring-type devices requiring 17 (π-phase shift) and 4 (switching between resonance and non-resonance with 6 dB extinction) mW of control power, respectively. We confirmed that the heating efficiency of all-optic control exceeded that of an electrical heater placed above the signal waveguide.
Witnessing multi-observer steering on both sides simultaneously via weak measurements
Authors: Liu Tong-Jun , Liu Kun , Fang Wei , Li Jian , Wang Qin
Published: October 2022

The quantum steering as an intermediate form of quantum correlations, has various peculiarities differing from the Bell nonlocality and the quantum entanglement. In a specific scenario, each side of the observer shares one of the two entangled qubits, steering can be witnessed simultaneously between any two observers from different sides by performing weak or projective measurements successively, with independently chosen and unbiased inputs. Here, we demonstrate this steering scenario experimentally to simultaneously witness quartic Einstein-Podolsky-Rosen steerings of two successive observers between each side with the entangled pair with a state fidelity of 97.6% compared with a maximally-entangled one.
Fast numerical propagation in high-NA imaging using the resampling angular spectrum method
Authors: Zhao Jian
Published: October 2022

Numerical propagation calculation is a fundamental research topic in optical engineering. The standard angular spectrum method (ASM) is accurate but time- and memory-consuming, especially for high-NA systems. In this work, we propose a fast and simple numerical propagation method, the resampling ASM (RS-ASM). Numerical propagation can be accelerated by combining a resampling technique with interpolation methods in the angular spectrum domain of a constrained object at the focal plane. RS-ASM has three main advantages: simple implementation, faster calculation than the standard ASM, and SNR enhancement. Here we validate RS-ASM using theory, simulation and experiment. Using the “bilinear” ASM with a proper resampling factor can result in a speed-up factor of up to 20x (for a transformation from the angular spectrum to the E field) and 4x (for a transformation from E field to the angular spectrum), together with a SNR improvement of approximately 2x. For an application example of Gerchberg-Saxton phase reconstruction, the “bilinear” RS-ASM can converge 2.6x faster than the standard ASM.
Fused optical fiber combiner based on indium fluoride glass: perspectives for mid-IR applications
Authors: Annunziato Andrea , Anelli Francesco , Du Teilleul Paul Le Pays , Cozic Solenn , Poulain Samuel , Prudenzano Francesco
Published: October 2022

For the first time, to the best of our knowledge, the design and characterization of a 3 × 1 fused fiber combiner based on multimode step-index fluoroindate optical fibers (InF3) has been performed. Several efforts to develop a well-consolidated normalization procedure and a fabrication protocol have been required due to the low melting temperature and the mechanical properties of fluoroindates. Fabrication results demonstrate repeatability and absence of crystallization. Therefore, the described fabrication process paves the way for manufacturing fluoroindate devices. The electromagnetic design of the combiner is carried out through modal investigation and beam propagation method by computing the transmission efficiency. The experimental results agree with the simulation and demonstrate the device feasibility to operate in the mid-infrared spectral range.
Recognition of centimeter-level length changes using the intensity of probe light in BOTDA
Authors: Chen Huan , Wang Tao , Zhang Qian , Liu Jingyang , Peng Jiaxin , Ge Xiaopeng , Zhang Jianzhong , Zhang Mingjiang
Published: October 2022

We proposed a method based on the Brillouin optical time domain analysis (BOTDA) system to demodulate the length changes of the heating region using the intensity of probe light, under the premise that the temperature in the heating region does not change and the Brillouin frequency shift (BFS) of the heating region is known. This method can realize the recognition of small length under the condition of wide pulse width. The theoretical analysis shows that the different lengths of the heating region will lead to different gains when the spatial resolution corresponding to the pulse width of the pulsed light is larger than the length of the heating region. And through theoretical derivation and simulation, it is concluded that the relationship between the intensity of probe light and the length of the heating region satisfies the exponential growth. Further experiments verify that the exponential growth is approximately linear in the range of small length changes. The length of the heating region can be inversely deduced by using the linear relationship by detecting the intensity of probe light. When the length of sensing fiber is 100 m and the heating region changes from 2 cm to 8 cm, 1 cm heating region changes can be identified.
Modal properties of dielectric bowtie cavities with deep sub-wavelength confinement
Authors: Kountouris George , Mørk Jesper , Denning Emil Vosmar , Kristensen Philip Trøst
Published: October 2022

We present a design for an optical dielectric bowtie cavity which features deep sub-wavelength confinement of light. The cavity is derived via simplification of a complex geometry identified through inverse design by topology optimization, and it successfully retains the extreme properties of the original structure, including an effective mode volume of Veff = 0.083 ± 0.001 (λc/2nSi)3 at its center. Based on this design, we present a modal analysis to show that the Purcell factor can be well described by a single quasinormal mode in a wide bandwidth of interest. Owing to the small mode volume, moreover, the cavity exhibits a remarkable sensitivity to local shape deformations, which we show to be well described by perturbation theory. The intuitive simplification approach to inverse design geometries coupled with the quasinormal mode analysis demonstrated in this work provides a powerful modeling framework for the emerging field of dielectric cavities with deep sub-wavelength confinement.
Pedestrian detection using a translation-invariant wavelet residual dense super-resolution
Authors: Hsu Wei-Yen , Chen Pei-Ci
Published: October 2022

Pedestrian detection is an important research area and technology for car driving, gait recognition, and other applications. Although a lot of pedestrian detection techniques have been introduced, low-resolution imaging devices still exist in real life, so detection in low-resolution images remains a challenging problem. To address this issue, we propose a novel end-to-end Translation-invariant Wavelet Residual Dense Super-Resolution (TiWRD-SR) method to upscale LR images to SR images and then use Yolov4 for detection to address the low detection problem performance on low-resolution images. To make the enlarged SR image not only effectively distinguish the foreground and background of images but also highlight the characteristic structure of pedestrians, we decompose the image into low-frequency and high-frequency parts by stationary wavelet transform (SWT). The high- and low-frequency sub-images are trained through different network structures so that the network can reconstruct the high-frequency image edge information and the low-frequency image structure in a more detailed manner. In addition, a high-to-low branch information transmission (H2LBIT) is proposed to import high-frequency image edge information into the low-frequency network to make the reconstructed low-frequency structure more detailed. In addition, we also propose a novel loss function, which enables the SR network to focus on the reconstruction of image structure in the network by the characteristics of wavelet decomposition, thereby improving its detection performance. The experimental results indicate that the proposed TiWRD-SR can effectively improve detection performance.
Design and characterization of “flow-cell” integrated-flow active cooling for high-average-power ceramic optics
Authors: Power E. P. , Bucht S. , Kafka K. R. P. , Bromage J. , Zuegel J. D.
Published: October 2022

We used COMSOL Multiphysics to design a prototype actively cooled “flow-cell” substrate targeted at high-average-power applications, fabricated the prototype from cordierite ceramic, and tested the substrate under load in our thermal loading test stand. Sub-aperture testing revealed average-power handling up to 3.88-W/cm2 absorbed power density, in excellent agreement with model predictions. Gratings fabricated on 2-in.-diam cordierite coupons were subjected to laser-damage testing and showed a damage threshold of 250 mJ/cm2.
Visible light emission enhancement from a graphene-based metal Fabry-Pérot cavity
Authors: Fan Yansong , Zhu Zhihong , Zhang Janfa , Xu Wei , Wu Fan , Yuan Xiaodong , Guo Chucai , Qin Shiqiao
Published: October 2022

The high saturation current density and ultrafast heating modulation of graphene makes it a competitive candidate for future thermal emission source. However, the low emissivity and easy oxidation under high temperature in air limit graphene application in the spectral range from the visible to near infrared. Here, we report a visible graphene thermal emitter based on the metal Fabry-Pérot (FP) cavity, which can greatly enhance the emissivity of graphene at wavelength around 637 nm and protect graphene from oxidation. We investigate the temperature characteristics of the emitter, and find the temperature of hot electrons in graphene is much higher than that of graphene lattice. Moreover, we also demonstrate the wavelength and intensity of graphene emission could be controlled by tuning the dielectric thickness between two gold layers. These results are helpful in the development of advanced graphene electro-thermal emission controlling application.
Electrically pumped InP/GaAsP quantum dot lasers grown on (001) Si emitting at 750 nm
Authors: Luo Wei , Lin Liying , Huang Jie , Lin Qi , Lau Kei May
Published: October 2022

Excellent performance of InAs quantum dot (QD) lasers grown on Si in the datacom and telecom bands has been reported in recent years. InP QD lasers on Si with emission wavelength at 650 nm–750 nm are seldom explored. In this paper, we report the growth and room temperature lasing of electrically pumped InP/GaAsP QD lasers directly grown on (001) Si emitting at 750 nm. The lowest threshold current density obtained is ∼650 A/cm2, measured on a 2 mm × 70 µm device. Moreover, the highest operating temperature of the InP QD laser grown on the GaAs/Si template is above 95°C. This 750 nm near red on-chip light source for the monolithic integration of Si photonics is potentially applicable in display, bio-photonics, and spatial mapping.
Flicker-free dual-volume augmented reality display using a pixelated interwoven integral floating technique with a geometric phase lens
Authors: Lee Hyeontaek , Lee Jae-Won , Shin JungYeop , Hong Sunghee , Kim Hak-Rin , Choi Hee-Jin
Published: October 2022

A geometric phase (GP) integral floating display can provide multifocal three-dimensional (3D) augmented reality (AR) images with enhanced depth expression by switching the focal modes of the GP lens via polarization control. However, using temporal multiplexing to switch between the focal modes of GP optics causes flickering as each 3D AR image is fully presented in different frames and their temporal luminance profile becomes easily recognizable, particularly as the number of available focal modes increases. Here, we propose a novel integral floating technique to generate pixelated interwoven 3D AR images; a half of each image is spatially mixed with another and presented in both focal modes simultaneously to resolve the flickering issue. The principle was verified via experimental demonstration and optically measured data.
Multiple resonant modes coupling enabled strong CD response in a chiral metasurface
Authors: Zong Shu , Zeng Dongwen , Liu Guiqiang , Wang Yan , Liu Zhengqi , Chen Jing
Published: October 2022

The chiral structures with strong circular dichroism (CD) response and narrow linewidth are desirable in chiral sensing, circularly-polarized light detection, and polarization imaging. Here, we theoretically proposed a hybrid chiral metasurface for differential absorption of circularly polarized light. Based on the multiple resonant modes coupling effect in a two-dimensional dielectric slab, it is realizable then to achieve a nearly perfect absorption for right circularly polarized light and simultaneously reflects 90% of left circularly polarized light, suggesting the generation of strong CD of 0.886 within a narrowly spectral linewidth of 4.53 nm. The multipole analysis reveals that the electric dipole, the magnetic dipole, and the electric quadrupole make dominant contributions to chiral absorption and the high CD response in this metsurface. The excitation of guided mode resonance enhances the ability of this metasurface to absorb electric field. Moreover, the optical chirality response can be further manipulated through the geometry features. These findings pave a powerful way to realize the narrowing and strong CD platform for single-band and multiband chirality behaviors.
Light field reconstruction in angular domain with multi-models fusion through representation alternate convolution
Authors: Cao Fengyin , Huang Xinpeng , An Ping , Yang Chao , Shen Liquan
Published: October 2022

To alleviate the spatial-angular trade-off in sampled light fields (LFs), LF super-resolution (SR) has been studied. Most of the current LFSR methods only concern limited relations in LFs, which leads to the insufficient exploitation of the multi-dimensional information. To address this issue, we present a multi-models fusion framework for LFSR in this paper. Models embodying LF from distinct aspects are integrated to constitute the fusion framework. Therefore, the number and the arrangement of these models together with the depth of each model determine the performance of the framework; we make the comprehensive analysis on these factors to reach the best SR result. However, models in the framework are isolated to each other as the unique inputs are required. To tackle this issue, the representation alternate convolution (RAC) is introduced. As the fusion is conducted successfully through the RAC, the multi-dimensional information in LFs is fully exploited. Experimental results demonstrate that our method achieves superior performance against state-of-the-art techniques quantitatively and qualitatively.
Phase-resolved all-fiber reflection-based s-NSOM for on-chip characterization
Authors: Sun Yizhi , Yan Xiaohong , Blaize Sylvain , Bachelot Renaud , Wei Hong , Ding Wei
Published: October 2022

We report on a phase-resolved, reflection-based, scattering-type near-field scanning optical microscope technique with a convenient all-fiber configuration. Exploiting the flexible positioning of the near-field probe, our technique renders a heterodyne detection for phase measurement and point-to-point frequency-domain reflectometry for group index and loss measurement of waveguides on a chip. The important issue of mitigating the measurement errors due to environmental fluctuations along fiber-optic links has been addressed. We perform systematic measurements on different types of silicon waveguides which demonstrate the accuracy and precision of the technique. With a phase compensation approach on the basis of a common-path interferometer, the phase drift error is suppressed to ∼ 0.013°/s. In addition, characterizations of group index, group velocity dispersion, propagation loss, insertion loss, and return loss of component waveguides on a chip are all demonstrated. The measurement accuracy of the propagation loss of a ∼ 0.2 cm long nano-waveguide reaches ±1 dB/cm. Our convenient and versatile near-field characterization technique paves the way for in-detail study of complex photonic circuits on a chip.
Multiple dipolar resonant silicon-based metamaterials for high-performance optical switching and sensing
Authors: Yang Hong , Zong Shu , Liu Guiqiang , Liu Xiaoshan , Fu Guolan , Liu Zhengqi
Published: October 2022

Dielectric nanostructures reinforcing light-matter interactions by manipulating geometric parameters have a sound momentum in optoelectronic applications. Here, we construct and numerically demonstrate a new platform with multiple dipolar resonant behaviors or impressive switching operation and optical sensing with a high sensitivity and figure of merit (FOM) via the graphene-silicon combined metamaterials. Ultra-sharp resonances are excited by introducing broken symmetry in such all-dielectric metamaterials (ADMs) consisting of two silicon trapezoidal bodies on a silica substrate. By analyzing the distributions of the electromagnetic fields and current densities, we find that two types of multipole modes have been excited to support multiple ultra-narrowband resonances in the near-infrared range. The influence of geometers, such as period, thickness, asymmetry parameters, and polarization angle of the incident light, has also been studied. In addition, by adjusting the Fermi levels of graphene, we realize a 95% amplitude modulation efficiency, which manifests perfect capacity for an optical switch. According to the calculated results, the highest sensitivity can reach 447.5 nm/RIU and a large FOM is also up to 1173 RIU−1. This platform not only introduces new insight onto the achievement of high-quality ultra-sharp resonant responses but also offers a distinct possibility for the further development of high-quality related applications in optical sensors, notch filtering, strong light-matter interactions including the nonlinear optics, and multispectral optoelectronics.
Supervised learning of soliton X-junctions in lithium niobate films on insulator
Authors: Bile Alessandro , Chauvet Mathieu , Tari Hamed , Fazio Eugenio
Published: October 2022

In this Letter, the first implementation, to our knowledge, of X-junctions between photorefractive soliton waveguides in lithium niobate-on-insulator (LNOI) films is reported. The experiments were performed on 8 µm thick films of congruent undoped LiNbO3. Compared with bulk crystals, the use of films reduces the soliton formation time, allows more control over the interaction between the injected soliton beams, and opens a route to integration with silicon optoelectronics functions. The created X-junction structures show effective supervised learning, directing the signals propagated inside the soliton waveguides into the output channels highlighted by the control assigned by the external supervisor. Thus, the obtained X-junctions have behaviors analogous to biological neurons.
Self-action effects in hyperbolic metamaterials based on gold nanorods
Authors: Kolmychek I. A. , Malysheva I. V. , Leontiev A. P. , Napolskii K. S. , Murzina T. V.
Published: October 2022

Intensive studies of hyperbolic metamaterials (HMMs) are induced by unique optical properties of this type of artificial media associated with their hyperbolic dispersion. Special attention is attracted to the nonlinear optical response of HMMs, which reveals anomalous behavior in definite spectral regions. Third-order nonlinear optical self-action effects that are perspective for applications were analyzed numerically, whereas such experiments have not been performed up to now. In this work we study experimentally the effects of the nonlinear absorption and refraction in ordered arrays of gold nanorods in porous aluminum oxide. We demonstrate strong enhancement and sign reversal of these effects in the vicinity of the epsilon-near-zero spectral point due to the resonant light localization and transition from elliptical to hyperbolic dispersion regimes.
Improved methods of binocular phase measuring deflectometry
Authors: Yan Ning , Wang Dongxue , Yin Shuangxiong , Guo Zhipeng , Zhang Xiaodong
Published: October 2022

Phase measurement deflectometry (PMD) is an excellent method for high-precision optical surface measurement; through the simple system structure, accuracy comparable to that of interference methods can be realized. The key of PMD is to solve the ambiguity between the surface shape and normal vector. Considering all kinds of methods, the binocular PMD method is undoubtedly a method with a very simple system structure and can be easily applied to complex surfaces, such as free-form surfaces. However, this method relies on a large screen with high accuracy, which not only increases the weight of the system, but also reduces the flexibility of the system, and manufacturing errors in the large-size screen can easily become error sources. In this Letter, we have made some improvements based on the traditional binocular PMD. At first, we try to replace the large screen with two small screens to increase the flexibility and accuracy of the system. Further, we replace one small screen with a single point to simplify the system structure. Experiments show that the proposed methods not only improve the system flexibility and reduce the complexity, but can also achieve high measurement accuracy.
Photonic integration of lithium niobate micro-ring resonators onto silicon nitride waveguide chips by transfer-printing
Authors: Li Zhibo , Smith Jack A. , Scullion Mark , Wessling Nils Kolja , McKnight Loyd J. , Dawson Martin D.
Published: October 2022

The heterogeneous integration of pre-fabricated lithium niobate
photonic waveguide devices onto a silicon nitride waveguide platform
via a transfer-printing approach has been demonstrated for the first
time. A fabrication process was developed to make free-standing
lithium niobate membrane devices compatible with back-end integration
onto photonic integrated circuits. Micro-ring resonators in membrane
format were lithographically defined by using laser direct writing and
plasma dry etching. The lithium niobate micro-ring resonators were
then transferred from their host substrate and released onto a silicon
nitride waveguide chip. An all-pass ring resonator transmission
spectrum was obtained in the 1.5 µm to
1.6 µm wavelength range, with a measured loaded Q-factor
larger than 3.2 × 104.
Circadian regulation of the transcriptome in a complex polyploid crop
Authors: Rees Hannah , Rusholme-Pilcher Rachel , Bailey Paul , Colmer Joshua , White Benjamen , Reynolds Connor , Ward Sabrina Jaye , Coombes Benedict , Graham Calum A. , de Barros Dantas Luíza Lane , Dodd Antony N. , Hall Anthony
Published: October 2022

The circadian clock is a finely balanced timekeeping mechanism that coordinates programmes of gene expression. It is currently unknown how the clock regulates expression of homoeologous genes in polyploids. Here, we generate a high-resolution time-course dataset to investigate the circadian balance between sets of 3 homoeologous genes (triads) from hexaploid bread wheat. We find a large proportion of circadian triads exhibit imbalanced rhythmic expression patterns, with no specific subgenome favoured. In wheat, period lengths of rhythmic transcripts are found to be longer and have a higher level of variance than in other plant species. Expression of transcripts associated with circadian controlled biological processes is largely conserved between wheat and Arabidopsis; however, striking differences are seen in agriculturally critical processes such as starch metabolism. Together, this work highlights the ongoing selection for balance versus diversification in circadian homoeologs and identifies clock-controlled pathways that might provide important targets for future wheat breeding.
Cryo-EM structures of LolCDE reveal the molecular mechanism of bacterial lipoprotein sorting in Escherichia coli
Authors: Bei Weiwei , Luo Qingshan , Shi Huigang , Zhou Haizhen , Zhou Min , Zhang Xinzheng , Huang Yihua
Published: October 2022

Bacterial lipoproteins perform a diverse array of functions including bacterial envelope biogenesis and microbe–host interactions. Lipoproteins in gram-negative bacteria are sorted to the outer membrane (OM) via the localization of lipoproteins (Lol) export pathway. The ATP-binding cassette (ABC) transporter LolCDE initiates the Lol pathway by selectively extracting and transporting lipoproteins for trafficking. Here, we report cryo-EM structures of LolCDE in apo, lipoprotein-bound, and AMPPNP-bound states at a resolution of 3.5 to 4.2 Å. Structure-based disulfide crosslinking, photo-crosslinking, and functional complementation assay verify the apo-state structure and reveal the molecular details regarding substrate selectivity and substrate entry route. Our studies snapshot 3 functional states of LolCDE in a transport cycle, providing deep insights into the mechanisms that underlie LolCDE-mediated lipoprotein sorting in E. coli.
OrthoSNAP: A tree splitting and pruning algorithm for retrieving single-copy orthologs from gene family trees
Authors: Steenwyk Jacob L. , Goltz Dayna C. , Buida Thomas J. , Li Yuanning , Shen Xing-Xing , Rokas Antonis
Published: October 2022

Molecular evolution studies, such as phylogenomic studies and genome-wide surveys of selection, often rely on gene families of single-copy orthologs (SC-OGs). Large gene families with multiple homologs in 1 or more species—a phenomenon observed among several important families of genes such as transporters and transcription factors—are often ignored because identifying and retrieving SC-OGs nested within them is challenging. To address this issue and increase the number of markers used in molecular evolution studies, we developed OrthoSNAP, a software that uses a phylogenetic framework to simultaneously split gene families into SC-OGs and prune species-specific inparalogs. We term SC-OGs identified by OrthoSNAP as SNAP-OGs because they are identified using a splitting and pruning procedure analogous to snapping branches on a tree. From 415,129 orthologous groups of genes inferred across 7 eukaryotic phylogenomic datasets, we identified 9,821 SC-OGs; using OrthoSNAP on the remaining 405,308 orthologous groups of genes, we identified an additional 10,704 SNAP-OGs. Comparison of SNAP-OGs and SC-OGs revealed that their phylogenetic information content was similar, even in complex datasets that contain a whole-genome duplication, complex patterns of duplication and loss, transcriptome data where each gene typically has multiple transcripts, and contentious branches in the tree of life. OrthoSNAP is useful for increasing the number of markers used in molecular evolution data matrices, a critical step for robustly inferring and exploring the tree of life.
Spatial clustering in vaccination hesitancy: The role of social influence and social selection
Authors: Alvarez-Zuzek Lucila G. , Zipfel Casey M. , Bansal Shweta
Published: October 2022

The phenomenon of vaccine hesitancy behavior has gained ground over the last three decades, jeopardizing the maintenance of herd immunity. This behavior tends to cluster spatially, creating pockets of unprotected sub-populations that can be hotspots for outbreak emergence. What remains less understood are the social mechanisms that can give rise to spatial clustering in vaccination behavior, particularly at the landscape scale. We focus on the presence of spatial clustering, and aim to mechanistically understand how different social processes can give rise to this phenomenon. In particular, we propose two hypotheses to explain the presence of spatial clustering: (i)social selection, in which vaccine-hesitant individuals share socio-demographic traits, and clustering of these traits generates spatial clustering in vaccine hesitancy; and (ii)social influence, in which hesitant behavior is contagious and spreads through neighboring societies, leading to hesitant clusters. Adopting a theoretical spatial network approach, we explore the role of these two processes in generating patterns of spatial clustering in vaccination behaviors under a range of spatial structures. We find that both processes are independently capable of generating spatial clustering, and the more spatially structured the social dynamics in a society are, the higher spatial clustering in vaccine-hesitant behavior it realizes. Together, we demonstrate that these processes result in unique spatial configurations of hesitant clusters, and we validate our models of both processes with fine-grain empirical data on vaccine hesitancy, social determinants, and social connectivity in the US. Finally, we propose, and evaluate the effectiveness of two novel intervention strategies to diminish hesitant behavior. Our generative modeling approach informed by unique empirical data provides insights on the role of complex social processes in driving spatial heterogeneity in vaccine hesitancy.
Ten simple rules on how to develop a stakeholder engagement plan
Authors: Hollmann Susanne , Regierer Babette , Bechis Jaele , Tobin Lesley , D’Elia Domenica
Published: October 2022

To make research responsible and research outcomes meaningful, it is necessary to communicate our research and to involve as many relevant stakeholders as possible, especially in application-oriented—including information and communications technology (ICT)—research. Nowadays, stakeholder engagement is of fundamental importance to project success and achieving the expected impact and is often mandatory in a third-party funding context. Ultimately, research and development can only be successful if people react positively to the results and benefits generated by a project. For the wider acceptance of research outcomes, it is therefore essential that the public is made aware of and has an opportunity to discuss the results of research undertaken through two-way communication (interpersonal communication) with researchers. Responsible Research and Innovation (RRI), an approach that anticipates and assesses potential implications and societal expectations regarding research and innovation, aims to foster inclusive and sustainable research and innovation. Research and innovation processes need to become more responsive and adaptive to these grand challenges. This implies, among other things, the introduction of broader foresight and impact assessments for new technologies beyond their anticipated market benefits and risks. Therefore, this article provides a structured workflow that explains “how to develop a stakeholder engagement plan” step by step.