bluuebunny/crossref_metadata_2025 huggingface dataset:
Οι διευκρινίσεις επί των προσφορών στις δημόσιες συμβάσεις
Authors: Γούπου Δέσποινα
Published: October 2024

Η παρούσα διδακτορική διατριβή φιλοδοξεί να παράσχει μια ολοκληρωμένη προσέγγιση του θεσμού των διευκρινίσεων των προσφορών στο δίκαιο των δημοσίων συμβάσεων τόσο από άποψη ουσιαστικού όσο και δικονομικού δικαίου. Η εκ βάθρων αναθεώρηση του λεκτικού και της δομής του άρθρου 102 του Ν. 4412/2016 με το άρθρο 42 του Ν. 4782/2021 δημιούργησε μια σειρά από ζητήματα και προβληματικές που αφορούν κυρίως το πεδίο εφαρμογής του νέου άρθρου 102, καθώς η νέα τροποποιηθείσα διατύπωση ήταν αρκετά πιο ευρεία, θέτοντας ως μοναδικό όριο για την εφαρμογή της διάταξης τις γενικές αρχές του δικαίου των δημοσίων συμβάσεων. Ως προς τις προϋποθέσεις εφαρμογής επιχειρήθηκε ήδη από το πρώτο Κεφάλαιο η χάραξη των ορίων του πεδίου εφαρμογής της νέας διάταξης τόσο σε θεωρητικό όσο και σε πρακτικό επίπεδο. Σε θεωρητικό επίπεδο, αναλύθηκαν οι γενικές αρχές του δικαίου των δημοσίων συμβάσεων οι οποίες και αποτελούν το μόνο όριο εφαρμογής της διάταξης το οποίο προβλέπεται ρητώς από το ίδιο το γράμμα του άρθρου 102 του Ν. 4412/2016. Επιπλέον αναλύθηκαν μια προς μια οι προϋποθέσεις που είχαν διαμορφωθεί υπό το φως της προϊσχύουσας διάταξης και εξετάστηκε με ερμηνευτικό εργαλείο τις γενικές αρχές του δικαίου των συμβάσεων, κατά πόσο οι προϋποθέσεις αυτές εξακολουθούν να ισχύουν και για το αναθεωρημένο άρθρο 102. Σε πρακτικό επίπεδο, επιχειρήθηκε η εξέταση των πιο συχνών περιπτώσεων ελλείψεων- σφαλμάτων που απαντούν στο πλαίσιο της εφαρμογής του άρθρου 102 του Ν. 4412/2016 και το κατά πόσο αυτές είναι ή πρέπει να είναι ιάσιμες δια του θεσμού των συμπληρώσεων – διευκρινίσεων του άρθρου 102 του Ν. 4412/2016. Στο δεύτερο κεφάλαιο επιχειρήθηκε η ερμηνευτική ανάλυση του άρθρου 102 του Ν. 4412/2016 υπό το πρίσμα του δικονομικού δικαίου. Στο πρώτο μέρος επιχειρήθηκε η εξέταση του κατά πόσο η κλήση προς παροχή διευκρινίσεων είναι ή πρέπει να αναγνωρίζεται ως εκτελεστή διοικητική πράξη αυτοτελώς προσβαλλόμενη ενώπιον της ΕΑΔΗΣΥ και των διοικητικών Δικαστηρίων. Σε δεύτερο στάδιο αναλύθηκε το κατά πόσο η επίκληση της δυνητικής εφαρμογής του άρθρου 102 του Ν. 4412/2016 παρίσταται ως δικονομικά λυσιτελής.
Comparative Analysis of Collagen Supplementation Forms and Their Effects on Multiple Health Parameters
Authors: Siemiątkowski Robert , Haber Mateusz , Czachor Adrianna , Kula Paula , Juśkiewicz Adam , Grelewicz Olga , Kucy Natalia , Servaas Elwira , Kotula Alicja
Published: October 2024

Collagen, a key structural protein, is essential for maintaining the integrity of connective tissues such as skin, cartilage, tendons, bones. As natural collagen production decreases with age and is further compromised by environmental factors such as UV radiation and poor diet, collagen degradation accelerates, leading to conditions like wrinkles, joint stiffness, and decreased bone density. Collagen supplementation has gained widespread attention as a therapeutic intervention to counteract these effects. This review conducts a comprehensive comparative analysis of various forms of collagen supplementation, including hydrolyzed collagen, undenatured collagen, and gelatin, and their effects on a range of health outcomes. Hydrolyzed collagen, due to enhanced bioavailability, is associated with improvements in skin elasticity, hydration, joint pain relief, and muscle recovery, making it particularly valuable for aging populations and athletes. Undenatured type II collagen, on the other hand, modulates immune responses and shows potential in reducing inflammation and slowing the progression of degenerative joint diseases such as osteoarthritis and rheumatoid arthritis. Gelatin, while less bioavailable than hydrolyzed collagen, still supports skin and joint health when taken in larger quantities. This review also explores emerging evidence of collagen’s beneficial effects on bone density, wound healing, and hair health, with marine-derived collagen showing promise in skin health due to its rapid absorption. Potential adverse effects, including mild gastrointestinal discomfort and rare allergic reactions, are discussed, emphasizing the importance of sourcing high-quality products. Overall, collagen supplementation, particularly hydrolyzed collagen peptides, offers significant therapeutic potential for improving skin, joint, and musculoskeletal health, but further research is required to define optimal dosages, formulations, and long-term safety for various populations.
Experiencia de educación interprofesional en salud: descripción e implementación en la Escuela de Medicina y Ciencias de la Salud de la Universidad del Rosario, Colombia
Authors: Aguía Rojas Karen
Published: October 2024

De acuerdo con el planteamiento de Hugh Barr (2009), la educación interprofesional (EIP) ocurre cuando dos o más profesiones aprenden con, desde y sobre el otro para mejorar la práctica colaborativa, la calidad de los cuidados y los servicios prestados. Este libro nace de las memorias y reflexiones de l a comunidad de aprendizaje de EIP en salud, evidenciando el complejo proceso del desarrollo de una iniciativa que involucra a siete programas de pregrado en una misma actividad. Aquí convergen los planteamientos epistemológicos, los resultados de aprendizaje, los diseños instruc- cionales y la integración curricular, sumados a las experiencias y retos enfrentados en la implementación de una estrategia pedagógica que, para finales de 2023, ya había sensibilizado a más de dos mil estudiantes y cerca de cincuenta docentes de la Escuela de Medicina y Ciencias de la Salud de la Universidad del Rosario, en el desafío de reconsiderar la identidad profesional y desfragmentar el cuidado de los pacientes, su familia y su comunidad.
Impact of Sleep Quality on Hemogram-Derived Inflammatory Indices in Medical Undergraduates: A Cross-Sectional Study
Authors: Garg Yash , T Jaseem , Rasalkar Kavita
Published: October 2024

The link between sleep-related disorders and inflammation is well-known, but the association between inflammatory indices and sleep deprivation is still unclear. In our study, we aimed to investigate the relationship between irregular sleep patterns and systemic inflammation using Hemogram-Based Inflammatory Indices. We collected demographic information from 90 undergraduate medical students through a confidential questionnaire. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Blood samples were obtained for complete blood count analysis, with platelet (P), lymphocyte (L), and neutrophil (N) counts measured. These values were then used to calculate hemogram-based inflammatory indices, including the Systemic Immune-Inflammation Index (SII), Platelet-to-Lymphocyte Ratio (PLR), and Neutrophil-to-Lymphocyte Ratio (NLR). A high prevalence of inconsistent sleep was observed among medical students, with 53% reporting a PSQI score greater than 5(mean score 5.9±2.9). Subjects with poor sleep quality had elevated SII values. Additionally, female participants who experienced poor sleep quality demonstrated a significant positive correlation with SII (r=0.322; p<0.049). Irregular sleep patterns are associated with greater systemic inflammation milieu specifically with SII compared to NLR and PLR. This effect was more pronounced in female participants, suggesting a potential gender-specific influence.
Highly efficient Tm-fiber laser resonantly pumped by a 1.7  µm laser diode
Authors: Šulc Jan , Němec Michal , Kratochvíl Jan , Jelínková Helena
Published: October 2024

A CW laser diode emitting at 1.7 µm was used to unidirectionally pump a thulium-doped fiber laser. A cladding-pumped fiber laser resonator consisted of a dichroic (high reflectivity at 2 µm, high transparency at 1.7 µm) free-space plane mirror, placed between two lenses used to collimate and to focus the pumping radiation, and Fresnel reflection of an active fiber end that serves as an output coupler. For an absorbed power of 11.5 W, an output power of 5.2 W was achieved at a wavelength 1950 nm with a slope efficiency of 70%. The goal of our work is to attract attention to the possibility of pumping thulium fiber lasers resonantly using laser diodes that are already readily available today. Thanks to resonant pumping, compared to cross-relaxation-assisted pumping at 0.8 µm, higher efficiency and lower heat generation can be achieved, which can help to reach high mean powers from thulium fiber lasers. An important fact is that both the generated laser radiation and pumping radiation belong to the eye-safe spectral region, which reduces the risk of vision damage.
Tunable electronic and optoelectronic characteristics of two-dimensional g-GeC monolayer: a first-principles study
Authors: Xu Zhong-Hui , Jiang Junlin , Wang Zhenyu , Wei Kaiyu , Liu Guogang , Ke San-Huang
Published: October 2024

Two-dimensional (2D) semiconductor materials have emerged as one of the hotspots in recent years due to their potential applications in beyond-Moore technologies. In this work, we systematically investigate the electronic and optoelectronic properties of the g-GeC monolayer combined with strain engineering using first-principles calculations. The results show that g-GeC monolayer possesses a suitable direct bandgap and a strain-tunable electronic structure. On this basis, the designed g-GeC monolayer-based two-probe photodetector exhibits a robust broadband optical response in the visible and near-ultraviolet ranges, along with significant polarization sensitivity and high extinction ratio. In addition, strain engineering can greatly improve the optoelectronic performance of the g-GeC-based photodetector and effectively tune its detection range in the visible and near-ultraviolet regions. These findings not only deepen the comprehension of g-GeC nanosheet but also provide the possibility of its application in nano-optoelectronic devices.
Single-step beam intensity and profile optimization using a 256 × 256 micromirror array and reinforcement learning
Authors: Xie Yunhui , Praeger Matthew , Grant-Jacob James A. , Mills Ben
Published: October 2024

Many optical applications require accurate control over a beam’s spatial intensity profile, in particular, achieving uniform irradiance across a target area can be critically important for nonlinear optical processes such as laser machining. This paper introduces a novel control algorithm for Digital Micromirror Devices (DMDs) that simultaneously and adaptively modulates both the intensity and the spatial intensity profile of an incident beam with random and intricate intensity variations in a single step. The algorithm treats each micromirror within the DMD as an independent Bernoulli distribution characterized by a learnable parameter. By integrating reinforcement learning with fully convolutional neural networks, we demonstrate that the control of 65,536 (256 × 256) micromirrors in a DMD can be achieved with modest computational expense. Furthermore, we implement the Error Diffusion (ED) algorithm as a sampling method and show that an incident beam with random and intricate intensity variations can be modulated to a predefined shape with high uniformity in intensity, both in simulated and experimental environments.
Optimal control of quantum permutation algorithm with a molecular ququart
Authors: Hu Jie-Ru , Zhang Zuo-Yuan , Liu Jin-Ming , Boninsegni Massimo
Published: October 2024

Quantum algorithms can afford greater computational efficiency compared to their classical counterparts when addressing specific computing tasks. We describe here the implementation, using a polar molecule in an external electric field, of the single-qudit cyclic permutation identification algorithm proposed by Gedik et al. [Sci. Rep. 5, 14671 (2015).10.1038/srep10995]. A molecular ququart is realized through the field-dressed states generated as the pendular modes of BaI. By employing multi-target optimal control theory, we design microwave pulses for ququart-based operations such as the Fourier transformation and its inverse, as well as the oracle U
f
operation. Specifically, we design an optimized pulse sequence that realizes a quantum algorithm on a single BaI molecule identifying the parity of a member of a set of cyclic permutations with high fidelity. This demonstrates the applicability of optimal control theory to polar molecules for quantum computation.
Double longitudinal-optical phonon intrawell scattering between two and three energy levels for depopulation in terahertz quantum cascade structures
Authors: Freeman Will
Published: October 2024

Terahertz quantum cascade structures using double longitudinal-optical phonon intrawell scattering between two and three energy levels, where ΔE ≥ 2ħωLO, for depopulating the lower lasing state are theoretically studied. The electron transport in two-well structures with diagonal optical transitions is calculated using a density matrix Monte Carlo method. Since the depopulation well is narrower when using two levels versus three, interface roughness scattering can dominate such that the device may not lase. It is shown that lowering the barrier heights to decrease the interface roughness effects using two depopulation levels allows for higher operating temperatures but with reduced performance compared to three levels, which has prospects for 300 K room temperature and beyond.
Experimental quantum teleportation of a Toffoli gate across three spatially distributed parties in a photonic quantum network
Authors: Dong Xiduo , Liu Shiting , Mao Ya-Li , Guo Bixiang , Xu Shufeng , Chen Hu , Guo Yuxiang , Li Zheng-Da , Fan Jingyun
Published: October 2024

Quantum computers may offer significant computational advantages over classical counterparts, revolutionizing the technology landscape in the near future. When networked together, the advantage of quantum computing may be further amplified, and there may emerge innovative applications. Among various active explorations on distributed quantum computing, multiqubit quantum gates between distant networked quantum computers are of particular interest because they offer operational advantages of efficiency and fidelity. Here we report the first experimental demonstration of quantum teleportation for a Toffoli gate, which is a commonly used multiqubit quantum gate, across three spatially distributed parties within a photonic quantum network. Employing the Hofmann method, we estimate the fidelity of the teleported Toffoli gate to be at least 0.706 ± 0.131. This successful demonstration of the quantum teleportation of a Toffoli gate constitutes a critical step toward the ultimate realization of distributed quantum computation.
Study on the mechanism of laser-induced breakdown and damage performance of internal defects in transparent materials through local optical field modulation
Authors: Liu Yubo , Cai Jixing , Zhou Yue , Qiu Jingxuan , Zhang Zequn , Yu Miao
Published: October 2024

This paper establishes a photothermal damage model for bubble impurities affecting laser optical field modulation based on Mie scattering theory and incorporates the effects of optical field modulation. This model elucidates the evolution mechanism of synergistic damage in fused silica, with simulation results validated through experimental verification. A novel characterization of optical breakdown due to bubble impurities is proposed, occurring on a millisecond timescale through the dynamic evolution of combustion waves. The model delineates the influence of bubble size and spacing on optical field distribution, temperature, stress distribution, and their evolutionary behaviors. The modulation of the optical field due to double bubble impurities creates a localized “hot spot,” resulting in a differential transverse contraction stress at the edges of the bubble impurities, thereby reducing the damage threshold of fused silica. The spacing of 1.1 λ represents the enhancement node for optical field modulation by double bubble impurities. Furthermore, localized oscillations in the optical field arise when the spacing between the double bubbles exceeds 1.1 λ, attributed to changes in the refractive index at the bubble defects and resonance oscillations generated by optical field modulation. This study not only enhances our understanding of the optical field modulation processes occurring at 1064 nm in the presence of bubble defects but also establishes a theoretical foundation for detecting internal defects at this wavelength without inducing surface damage.
Vortex solitons in rotating quasi-phase-matched photonic crystals
Authors: Chen Shunfang , Zhou Boai , Jiao Yida , Wang Linjia , Zhao Yuan , Xu Siliu
Published: October 2024

We present an approach to generate stable vortex solitons (VSs) in rotating quasi-phase-matched photonic crystals with quadratic nonlinearity. The photonic crystal is introduced with a checkerboard structure, which can be realized using available technology. The VSs are constructed as four-peak vortex modes of two types: rhombuses and squares. Control parameters, including the power, rotating frequency, and size of each square cell, affect the distribution and stability range of these VSs. The tightly binding rhombic VSs realize the system’s ground state, which features the lowest value of the Hamiltonian. By introducing rotation, stable VSs with topological charges l = ±1 and ±2 are observed, and the VSs turn from a quadrupole to a vortex-like state. The generation and modulation of stable VSs in rotating quasi-phase-matched photonic crystals demonstrate promising applications in optical communication systems, optical tweezers, and quantum information processing, where precise control over light propagation and vortex states is crucial.
Low-loss, single-polarization, anti-bending, anti-resonant fiber applicable to the small flexibility field
Authors: Zhou Jingkai , Wang Feng , Song Yuejiang , Li Mi , Mao Peng , Chen Qiang
Published: October 2024

In this paper, a novel hollow-core anti-resonant optical fiber is proposed. We confirm that the U-shaped nested tubes can better compress the fiber core compared with the circular and semi-circular nested tubes to further reduce the loss and improve the single polarization characteristics. The proposed optical fiber has an ultra-low loss of 0.005 dB/m in the considered wavelength range. This is difficult to achieve in most of the previous studies. In the common wavelength band of 1550 nm, the designed fiber achieves a birefringence of about 3 × 10−5 and a single polarization PER index of 2259 and is capable of polarization filtering with a broadband of 16 nm. Meanwhile, the proposed structure still has extremely excellent bending resistance. The critical bending radius of the designed structure is approximately 0.4 cm. It also confirms that our proposed structure has a certain ability to withstand harsh environments and can be widely applied in small, flexible fields. We believe that the designed structure has a wider range of applications in the field of fiber optic communication systems that are more sensitive to polarization, such as fiber optic gyroscopes, optical amplifiers, and fiber lasers.
Efficient cryogenic orange Pr3+:YLF lasers
Authors: Kalusniak Sascha , Badtke Moritz , Püschel Stefan , Hahn Ole , Tanaka Hiroki , Kränkel Christian
Published: October 2024

We present experimental evidence that the efficiency of orange Pr3+ lasers is limited by losses due to ground state absorption. To this end, we determined the temperature-dependent orange reabsorption and performed laser experiments with orange Pr3+:YLF lasers at 604 nm and 607 nm in the temperature range between 78 K and 295 K. At 110 K, a slope efficiency of 67% and an optical-to-optical efficiency of 64% are obtained. These are the highest efficiencies of any orange-emitting Pr3+ lasers to the best of our knowledge, enabled by vanishing reabsorption for the orange laser emission at low temperatures.
LUT-based phase error compensation method for large-step phase-shifting algorithm in DLP4500-based FPP system
Authors: Qiu Jiancheng , Liu Ganhua , Xi Dejun , Wu Gaoxu
Published: October 2024

As a low-cost professional digital light projection device, the DLP4500 have been widely applied in fringe projection profilometry (FPP), for both laboratory and practical application. However, our recent experiments revealed a new hardware-induced projection instability when the projection pattern data exceeds its buffer capacity (48 bits). This phenomenon undermines the measurement accuracy advantage of the phase-shifting (PS) algorithms with large number of shifting steps, and eventually leads unwanted and complicated error to 3D reconstruction. In this paper, we experimentally investigate the new hardware-induced phase error and proposed a LUT-based phase error compensation method. In this method, a standard plate with a precision manufactured plate is used as the standard reference for the phase error evaluation, where an ideal plane fitting and the projector pixel reprojection process are introduced to generate the ideal reference phase. Comprehensive experiments are conduct to verify the stability of the proposed method in LUT creation. Comprehensive experiments are conduct, and the results show that (i) the method works creates LUTs stably at different plate positions, (ii) the plate with regular manufacturing accuracy (not exceeding 0.01 mm) can meet the application requirements of the proposed method. Both quantitative and qualitative experimental results successfully verify the effectiveness of proposed method in LUT creation and phase error reduction.
Electrical liquid crystal integration with VCSEL arrays for tunable orthogonal polarization laser
Authors: Dai Yucheng , Shi Linlin , Song Yingmin , Zou Yonggang , Fan Jie , Fu Xiyao , Ma Xiaohui
Published: October 2024

Vertical-cavity surface-emitting laser (VCSEL) arrays that can emit orthogonally polarized light have shown broad application potential and market demand in the fields of optical communication, optical sensors, and biomedicine. Two kinds of polarization-switching VCSEL arrays based on anti-parallel (AP) oriented liquid crystal (LC) external cavities and twisted nematic (TN) oriented LC external cavities are proposed in this paper. The light is independently guided by the LC electrically, achieving uniform lasing of linearly polarized light with mutually orthogonal polarization modes and equal power. The uniformity and polarization tunable ability of the lasing orthogonally polarized light power is guaranteed by the integration of the LC external cavity and the VCSEL array.
Impact of modal gain and waveguide design on two-state lasing in quantum well-dot lasers
Authors: Maximov M. V. , Shernyakov Yu. M. , Kornyshov G. O. , Beckman A. A. , Zubov F. I. , Kharchenko A. A. , Payusov A. S. , Mintairov S. A. , Kalyuzhnyy N. A. , Dubrovskii V. G. , Gordeev N. Yu.
Published: October 2024

We study the current-controlled lasing switching from the ground state (GS) to the excited state (ES) transition in broad-area (stripe width 100 µm) InGaAs/GaAs quantum well-dot (QWD) and quantum well (QW) lasers. In the lasers with one QWD layer and a 0.45 µm-thick GaAs waveguide, pure GS lasing takes place up to an injection current as high as 8 A (40 kA/cm2). In contrast, in QW lasers with a similar design, ES lasing emerges already at 3 A (15 kA/cm2). The ES lasing in the QWD lasers is observed only in the devices with a waveguide thickness of 0.78 µm that supports a 2nd order transverse mode at the wavelength of the ES transition. Increasing the modal gain in the lasers with 0.78 µm-thick waveguide by using two QWD layers in the active region suppresses the ES lasing.
Dual-mode 2 × 2 electro-optic switch on a SOI platform
Authors: Ding Yingzhi , Zhang Daming , Zhang Peng , Tang Bo , Wang Fei , Wang Xibin , Yokoyama Shiyoshi , Yin Yuexin
Published: October 2024

Mode-division multiplexing (MDM) technology is promising for enhancing the capacity of communication networks. In this Letter, we demonstrate a dual-mode 2 × 2 electro-optical switch on a silicon-on-insulator platform. The dual-mode Mach–Zehnder interferometer switch comprises of four p-i-n phase shifters and two mode-insensitive multimode interferences that can be used for TE0 and TE1, simultaneously. With π/2 phase shifters introduced, push–pull like operation enables the power consumption lower than 2.15 mW. The average insertion loss of the switch in “cross” and “bar” states are 1.31 dB ± 0.19 dB for the TE0 mode and 3.39 dB ± 0.16 dB for the TE1 mode, respectively. The cross talk is less than −16.47 dB in the C band. The compact dual-mode switch is promising to conduct a large-scale, flexible MDM system on chip.
Generation of a MW-class tunable Raman soliton up to 3.8 µm in a fluorotellurite fiber
Authors: Yang Linjing , Yao Chuanfei , Wang Xuan , Meng Xianghao , Ren Guochuan , Pu Luyao , Li Kaihang , Li Pingxue
Published: October 2024

We report the generation of MW-class tunable Raman solitons of 3.3–3.8 µm in a fluorotellurite fiber. The pump source of the mid-infrared fiber is a 2.15–2.3 µm Raman soliton source which has the highest peak-power Raman soliton (3.8 MW) ever achieved in a silica fiber. Fluorotellurite fiber is characterized by its short length and high nonlinearity, preventing the Raman soliton pulse broadening that occurs with fiber dispersion. The Raman soliton shifted to 3.8 µm while still maintaining an ultra-narrow pulse width of 70.4 fs with 1.36 W output power and 1.17 MW peak power. To the best of our knowledge, this is the highest peak-power Raman soliton obtained in a mid-infrared fiber.
Chirality-controlled second-order nonlinear frequency conversion in lithium niobate film metasurfaces
Authors: Xu Hangsheng , Ma Ruize , Zhu Ying , Dong Anlong , Jiang Haiyan , Gao Weiqing , Qin Meng , Liu Jianqiang , Wu Feng , Li Hongju
Published: October 2024

The high-quality factor resonant metasurfaces have extensive applications in enhancing nonlinear frequency conversion efficiency at the subwavelength scale. However, methods for actively modulating the frequency conversion process are limited. We design a chiral lithium niobate film metasurface and investigate the photonic spin as a new degree of freedom to dynamically control the second-order nonlinear frequency conversion, without reconfiguring the structure by using external stimuli. The chiral resonance with circular dichroism (CD) of 0.62 gives rise to a high nonlinear CD of 0.84 in second-harmonic generation efficiency. Interestingly, combining the chiral resonance and an achiral quasi-bound state in the continuum enables us to investigate the photonic-spin-controlled sum-frequency generation and the photon pair generation from the spontaneous parametric downconversion process. Owing to the ultrahigh quality factor exceeding 103 both for two resonances, the second-order nonlinear frequency conversion occurs at a wavelength region of 0.2 nm, suggesting good monochromaticity. Our work opens new, to our knowledge, avenues for practical implementation of dynamically controlled nonlinear optical devices and will find utility in holography, switchable light sources, and information processing.
Controllable temporal twisting polarization within an ultrafast laser pulse
Authors: Jiang Xuanren , Zhou Zhangyu , Min Changjun , Zhang Yuquan , Yuan Xiaocong
Published: October 2024

We propose a method for controlling the time-varying polarization of optical pulses by introducing a quarter-wave plate into a 4-f pulse shaper and using a spatial light modulator to impose a group delay. This setup enables the polarization state of the incident pulse to vary over time. Specifically, for linearly chirped incident pulses, the polarization ellipse twists uniformly over time, while its ellipticity changes monotonically. As the group delay increases, the pulse intensity gradually splits in the time domain, transitioning from a single pulse with uniformly twisting polarization to two circularly polarized pulses with opposite chirality. We provide a detailed and comprehensive explanation of this modulation process using analytical expressions.
Asynchronous wide-field transient absorption microscopy
Authors: Zhang He , Li Zhixuan , Hou Feiyang , Xu Chunxiang , Cui Qiannan
Published: October 2024

We have developed a new, to the best of our knowledge, femtosecond laser spatiotemporal imaging technique, named asynchronous wide-field transient absorption microscopy (AWTAM), which does not require phase synchronization between an optical chopper and a complementary metal–oxide–semiconductor (CMOS) camera. By presenting a theoretical scheme, an image reconstruction algorithm, and experimentally imaging the photocarrier diffusion process in a 2D layered semiconductor, our technique has been comprehensively demonstrated. Our technique is widely applicable for fundamental photo-physical research and industrial applications, with the advantages of lower hardware cost as well as higher imaging speed.
Real-time fully digital control scheme for pulse coherent beam combining
Authors: Wu Yong , Wang Xinyu , Pu Guoqing , Zhang Xuguang , Liu Chenxu , Dong Kegong , Hu Weisheng , Yi Lilin
Published: October 2024

A fully digital control scheme for non-polarization-maintaining (non-PM) nanosecond pulse coherent beam combining (CBC) is proposed, where digital locking of optical coherence by single-detector electronic-frequency tagging (LOCSET) for active phase control and stochastic parallel gradient descent (SPGD) for active polarization control is proposed. The fully digital control scheme is integrated on a real-time field-programmable gate array (FPGA) empowered hardware platform and then experimentally validated in a four-channel all-fiber non-fully polarization-maintaining nanosecond pulse CBC system. Consequently, the system can be fully locked in 9.5 ms, and the polarization extinction ratio (PER) of the combined beam is 21.5 dB with a CBC efficiency of 95.3%. The fully digital control scheme integrates the advantages of digital LOCSET and multi-channel active polarization control, enhancing the channel scalability and the potential output power of the non-PM pulse CBC system.
Coherent dynamics in an optical quantum dot with phonons and photons
Authors: DeCrescent Ryan A. , Wang Zixuan , Bush Joey T. , Imany Poolad , Kwiatkowski Alex , Reddy Dileep V. , Nam Sae Woo , Mirin Richard P. , Silverman Kevin L.
Published: October 2024

Genuine quantum-mechanical effects are readily observable in modern optomechanical systems comprising “classical” (bosonic) optical resonators. Unique features and advantages of optical two-level systems (qubits) for optomechanics, however, have not been so thoroughly explored. We experimentally demonstrate these advantages using charge-controlled InAs quantum dots (QDs) in surface-acoustic-wave resonators. We coherently control QD population dynamics using engineered optical pulses and mechanical motion, i.e., using both phonons and photons. As a first example, at moderate acoustic drive strengths, we demonstrate the potential of this technique to maximize fidelity in quantum microwave-to-optical transduction. Specifically, the scheme is tailored to enhance mechanically assisted photon scattering over the direct detuned photon scattering from the QD. Spectral analysis reveals distinct scattering channels related to Rayleigh scattering and luminescence in our pulsed excitation measurements, which lead to time-dependent scattering spectra. Quantum-mechanical calculations show good agreement with our experimental results, together providing a comprehensive description of excitation, scattering, and emission in a coupled QD-phonon system. These results highlight unique opportunities to expand the functionality of quantum optomechanical systems.
Magnetically tunable bound states in the continuum with arbitrary polarization and intrinsic chirality
Authors: Tu Qing-An , Zhou Hongxin , Zhao Dong , Meng Yan , Gong Maohua , Gao Zhen
Published: October 2024

Bound states in the continuum (BICs), which are exotic localized eigenstates embedded in the continuum spectrum and exhibit topological polarization singularities in momentum space, have recently attracted great attention in both fundamental and applied physics. Here, based on a magneto-optical (MO) photonic crystal (PhC) slab placed in external magnetic fields with time-reversal symmetry (TRS) breaking, we theoretically propose magnetically tunable BICs with arbitrary polarization covering the entire Poincaré sphere and efficient off-Γ chiral emission of circularly polarized states (C point). More interestingly, by further breaking the in-plane inversion symmetry of the MO PhC slab to generate a pair of C points spawning from the eliminated BICs and tuning the external magnetic field strength to move one C point to the Γ point, an at-Γ intrinsic chiral BIC exhibits chiral characteristics on both sides of the PhC slab with near-unity circular dichroism exceeding 0.99 and a high-quality factor of 46,000 owing to the preserved out-of-plane mirror symmetry. Moreover, the chirality of the chiral BICs can be inverted by flipping the magnetic bias. Our work opens an unprecedented avenue to explore the unique topological photonics of BICs with broken TRS and promises multiple applications in chiral-optical effects, structured light, and tunable optical devices.
Unifying approaches from statistical genetics and phylogenetics for mapping phenotypes in structured populations
Authors: Schraiber Joshua G. , Edge Michael D. , Pennell Matt
Published: October 2024

In both statistical genetics and phylogenetics, a major goal is to identify correlations between genetic loci or other aspects of the phenotype or environment and a focal trait. In these 2 fields, there are sophisticated but disparate statistical traditions aimed at these tasks. The disconnect between their respective approaches is becoming untenable as questions in medicine, conservation biology, and evolutionary biology increasingly rely on integrating data from within and among species, and once-clear conceptual divisions are becoming increasingly blurred. To help bridge this divide, we lay out a general model describing the covariance between the genetic contributions to the quantitative phenotypes of different individuals. Taking this approach shows that standard models in both statistical genetics (e.g., genome-wide association studies; GWAS) and phylogenetic comparative biology (e.g., phylogenetic regression) can be interpreted as special cases of this more general quantitative-genetic model. The fact that these models share the same core architecture means that we can build a unified understanding of the strengths and limitations of different methods for controlling for genetic structure when testing for associations. We develop intuition for why and when spurious correlations may occur analytically and conduct population-genetic and phylogenetic simulations of quantitative traits. The structural similarity of problems in statistical genetics and phylogenetics enables us to take methodological advances from one field and apply them in the other. We demonstrate by showing how a standard GWAS technique—including both the genetic relatedness matrix (GRM) as well as its leading eigenvectors, corresponding to the principal components of the genotype matrix, in a regression model—can mitigate spurious correlations in phylogenetic analyses. As a case study, we re-examine an analysis testing for coevolution of expression levels between genes across a fungal phylogeny and show that including eigenvectors of the covariance matrix as covariates decreases the false positive rate while simultaneously increasing the true positive rate. More generally, this work provides a foundation for more integrative approaches for understanding the genetic architecture of phenotypes and how evolutionary processes shape it.
Surface exclusion of IncC conjugative plasmids and their relatives
Authors: Rivard Nicolas , Humbert Malika , Huguet Kévin T. , Fauconnier Aurélien , Bucio César Pérez , Quirion Eve , Burrus Vincent
Published: October 2024

The phenomenon of exclusion allows conjugative plasmids to selectively impede the entry of identical or related elements into their host cell to prevent the resulting instability. Entry exclusion blocks DNA translocation into the recipient cell, whereas surface exclusion destabilizes the mating pair. IncC conjugative plasmids largely contribute to the dissemination of antibiotic-resistance genes in Gammaproteobacteria. IncC plasmids are known to exert exclusion against their relatives, including IncC and IncA plasmids, yet the entry exclusion factor eexC alone does not account for the totality of the exclusion phenotype. In this study, a transposon-directed insertion sequencing approach identified sfx as necessary and sufficient for the remaining exclusion phenotype. Sfx is an exclusion factor unrelated to the ones described to date. A cell fractionation assay localized Sfx in the outer membrane. Reverse transcription PCR and beta-galactosidase experiments showed that sfx is expressed constitutively at a higher level than eexC. A search in Gammaproteobacteria genomes identified Sfx homologs encoded by IncC, IncA and related, untyped conjugative plasmids and an uncharacterized family of integrative and mobilizable elements that likely rely on IncC plasmids for their mobility. Mating assays demonstrated that sfx is not required in the donor for exclusion, ruling out Sfx as the exclusion target. Instead, complementation assays revealed that the putative adhesin TraN in the donor mediates the specificity of surface exclusion. Mating assays with TraN homologs from related untyped plasmids from Aeromonas spp. and Photobacterium damselae identified two surface exclusion groups, with each Sfx being specific of TraN homologs from the same group. Together, these results allow us to better understand the apparent incompatibility between IncA and IncC plasmids and to propose a mechanistic model for surface exclusion mediated by Sfx in IncC plasmids and related elements, with implications for the rampant dissemination of antibiotic resistance.
Trends and key disparities of obesity among US adolescents: The NHANES from 2007 to 2020
Authors: Deng Yangyang , Yli-Piipari Sami , El-Shahawy Omar , Tamura Kosuke
Published: October 2024

This study aimed to estimate the trends in the body mass index (BMI) and prevalence of obesity among United States (U.S.) adolescents (10–19 years) and to examine the associations between sociodemographic factors and both BMI and obesity prevalence. The 2007–2020 National Health and Nutrition Examination Survey (NHANES), a nationally representative repeated cross-sectional survey data (n = 9,826) were used. Outcomes included: 1) Mean BMI and 2) obesity (yes/no; defined as BMI ≥95% percentile). Sociodemographic variables included age, sex, race/ethnicity, and poverty income ratio (PIR; low-income <1.3, middle-income ≥1.3 and <3.5, high-income ≥3.5). By accounting for the complex survey design, weighted generalized linear/Poisson models were used to conduct the analyses. Girls constituted 49% of the sample. From 2007–2008 to 2017–2020, there was an increase in BMI and obesity prevalence, particularly among Black and Hispanic adolescents, and those from low- and middle-income families. Additionally, there was an increase in obesity prevalence among both boys and girls. However, there were no significant changes in BMI and obesity prevalence in the other race and ethnic adolescents. Girls had a 12% (Adjusted Prevalence Ratio [APR] = 0.88; 95% CI, 0.81–0.96) lower likelihood of being obese than boys. Compared to White adolescents, Black and Hispanic adolescents had 22% (APR = 1.22; 95% CI, 1.06–1.40) and 19% (APR = 1.19; 95% CI, 1.05–1.36) greater risk of being obese. Compared to high-income families, adolescents from low- and middle-income families had 62% (APR = 1.62; 95% CI, 1.39–1.90) and 47% (APR = 1.47; 95% CI, 1.24–1.76) greater risk of being obese, respectively. The results indicated persistent disparities in obesity prevalence among different race/ethnic and sociodemographic groups. Future obesity intervention should address key disparities by targeting specific race/ethnic adolescents from low-income families and promoting health equality.
Between land and sea: A multidisciplinary approach to understand the Early Occupation of Sicily (EOS)
Authors: Patania Ilaria , Ogloblin Ramirez Isaac , Carroll Peyton , Wroth Kristen , Zaia Sara , Di Mauro Sebastiano , Falci Danielle , Querenet Onfroy de Breville Iris , Aguilar Lazagabaster Ignacio , Minniti Gianmarco , Reitano Agatino , Insacco Gianni , Kidder Tristram , Tryon Christian
Published: October 2024

The island of Sicily is considered to be among the first occupied by humans in the European Upper Paleolithic. Studies to understand early occupation of the island are mostly concentrated on the northern shores. Our project, Early Occupation of Sicily (EOS), focuses on southeastern Sicily so to address questions regarding dispersal to Mediterranean islands and Late Pleistocene landscapes and environments. Here, we present the initial results of our terrestrial and underwater surveys in combination with archival work and analyses of museum collections. In SE Sicily very few Upper Paleolithic sites have been excavated and analyzed using scientific methods. We have relocated and assessed ~20 caves and rock shelters identified between the 1870s and 1990s, studied museum collections, and collected raw material to reconstruct procurement patterns. To identify new sites, we conducted land and underwater surveys to reconstruct paleo-shorelines and past environments. We have identified three sites, two on land and one partially submerged, that still contain unexplored archaeological sediments, demonstrated in one instance through seismic tomography. This work shows the potential of re-examining minimally studied sites and materials to reconstruct mobility patterns and environmental impact of the first inhabitants of the island.
Capacity analysis of short-distance continuous diversion areas on mountainous urban expressways
Authors: Cai Xiaoyu , Jin Ling , Peng Bo , Li Yongqi , Chen Yang
Published: October 2024

The short-distance continuous diversion area plays a crucial role within mountainous urban expressway systems, significantly enhancing the efficiency of specialized road sections through capacity analysis. This study develops a capacity calculation model tailored to the diversion area’s unique characteristics and principal capacity-influencing factors. Initially, the research focuses on a specific short-distance continuous diversion area of a mountainous urban expressway, employing video trajectory tracking technology to gather trajectory data. This data serves as the basis for analyzing road and traffic characteristics. Subsequently, the model computes the capacity influenced by eight variables, including diversion point spacing and deceleration lane length, using VISSIM simulation experiments. A gray correlation analysis identifies key factors, which guide the establishment of the model’s fundamental structure through two-factor surface fitting results. Mathematical statistical methods are then applied to resolve the model’s parameters, culminating in a robust capacity calculation model. The findings reveal that diversion point spacing, along with primary and secondary diversion ratios, significantly influence capacity. Notably, the capacity exhibits a marked quadratic polynomial relationship with the primary diversion ratio and diversion point spacing, and a linear relationship with the secondary diversion ratio. The model’s validity is confirmed through a case study at the diversion area north of Huacun Interchange in Chongqing Municipality, where the discrepancy between calculated and actual capacities is under 5%, underscoring the model’s high accuracy. These results offer valuable theoretical and methodological support for the planning, design, and traffic management of diversion areas.
Evaluation of flood metrics across the Mississippi-Atchafalaya River Basin and their relation to flood damages
Authors: Schilling Keith E. , Anderson Elliot S. , Mount Jerry , Suttles Kelly , Gassman Philip W. , Cerkasova Natalja , White Michael J. , Arnold Jeffrey G.
Published: October 2024

Societal risks from flooding are evident at a range of spatial scales and climate change will exacerbate these risks in the future. Assessing flood risks across broad geographical regions is a challenge, and often done using streamflow time-series records or hydrologic models. In this study, we used a national-scale hydrological model to identify, assess, and map 16 different streamflow metrics that could be used to describe flood risks across 34,987 HUC12 subwatersheds within the Mississippi-Atchafalaya River Basin (MARB). A clear spatial difference was observed among two different classes of metrics. Watersheds in the eastern half of the MARB exhibited higher overall flows as characterized by the mean, median, and maximum daily values, whereas western MARB watersheds were associated with flood indicative of high extreme flows such as skewness, standardized streamflow index and top days. Total agricultural and building losses within HUC12 watersheds were related to flood metrics and those focused on higher overall flows were more correlated to expected annual losses (EAL) than extreme value metrics. Results from this study are useful for identifying continental scale patterns of flood risks within the MARB and should be considered a launching point from which to improve the connections between watershed scale risks and the potential use of natural infrastructure practices to reduce these risks.
Exploring the phytochemicals, antioxidant properties, and hepatoprotective potential of Moricandia sinaica leaves against paracetamol-induced toxicity: Biological evaluations and in Silico insights
Authors: Aly Shaza H. , Mahmoud Abdulla M. A. , Abdel Mageed Sherif S. , Khaleel Eman F. , Badi Rehab Mustafa , Elkaeed Eslam B. , Rasheed Rabab Ahmed , El Hassab Mahmoud A. , Eldehna Wagdy M.
Published: October 2024

Thirteen components were identified in the methanol extract of Moricandia sinaica leaves (MSLE) through analysis utilizing HPLC-ESI-MS/MS., including flavonoids, anthocyanins, phenolic acids, and fatty acids. The methanol extract of M. sinaica leaves contained total phenolics and flavonoids (59.37 ± 2.19 mg GAE/g and 38.94 ± 2.72 mg QE/g), respectively. Furthermore, it revealed in vitro antioxidant properties as determined by the DPPH and FRAP assays, with respective IC50 values of 10.22 ± 0.64 and 20.89 ± 1.25 μg/mL. The extract exhibited a notable hepatoprotective effect in rats who experienced paracetamol-induced hepatotoxicity. When a dose of 250 mg/kg was given, there was a 52% reduction in alanine transaminase and a 30% reduction in aspartate transaminase compared to the group with the disease. Furthermore, it demonstrated a 3.4-fold, 2.2-fold, and 2.6-fold increase in superoxide dismutase, non-protein sulfhydryl, and glutathione peroxidase, respectively. In addition, it demonstrated a 68% decrease in lipid peroxide levels compared to the group with paracetamol-induced condition. The verification was conducted using a histological study, which identified improved liver histology with a small number of distended hepatocytes. Moreover, in silico studies focused on the enzymes NADPH oxidase, butyrylcholinesterase, and tyrosinase as the targets for the major compounds. In conclusion, MSLE showed promising hepatoprotective and antioxidant activities due to its richness in antioxidant metabolites.