bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of car rental business in travel and tourism industry: A Case study of rent a car companies in Lefkada Island
Authors: Kalli Sofia , Avramopoulos Avraam
Published: June 2023

The present research refers to the role of car rental in the travel industry with a case study on the island of Lefkada. The agencies in the car rental industry have received a great deal of attention in recent years, due to the fact that they have shown immense growth in and out of Greece. In Greece, the car rental industry is most often associated with tourism as it presents the largest turnover of tourists-customers.

In the present paper, rent-a-car agencies in the island of Lefkada are canvassed in the literature and research field with the aim of drawing conclusions in relation to their basic features and the quantitative and quality depiction of their workforce. Regarding the research process, a quantitative and qualitative research was carried out. The main tool used in the quantitative research was the questionnaire which was distributed to agencies operating in the field of the car rental industry in the island of Lefkada. The tool of the qualitative research was the interview, which took place in three agencies through face-to-face meetings with their executives. The results indicated that the course of the Greek car rental market, in recent years, is on the rise, which creates a positive climate for the development and progress of the industry. Finally, certain suggestions for future research based on the conclusions are the study on European Funds and NSRF programs for the purchase of electric cars and the simplification of procedures, i.e. the automatization of most actions such as online check.

JEL Classifications: L83, L91, M21

Key words: short-term vehicle leases, vehicle rental, types of vehicle leases, management of car rental agencies.
A comprehensive review of energy efficient routing protocols for query driven wireless sensor networks
Authors: Bekal Punith , Kumar Pramod , Mane Pallavi R , Prabhu Ghanshyam
Published: June 2023

In this current era of communications and networking, The Internet of things plays the main role in the making of smart communication and networking. In this article, we have focused on the literature survey on wireless sensor networks which are energy efficient. Various standard protocols are reviewed along with some enhanced protocols which makes the network energy efficient. The comparison of the standard and enhanced protocols with respect to various applications in wireless sensor networks is thoroughly done in this article. The outcomes of the enhanced protocols are also briefly discussed. For easier analysis to future researchers, a comparative table which lists the enhanced protocols which are compared with standard counterparts along with the factors for energy efficiency of the protocols. This article also comments on the issues and challenges of the protocols which can be further analyzed for making the wireless sensor network more energy efficient.
Gastronot: a pilot project for promoting healthy eating habits using mixed-method study design
Authors: Respati Titik , Fitriyana Susan , Romadhona Nurul , Ibnusantosa Ganang , Frederrico Rio , Yulianto Fajar Awalia , Shandriasti Aughya , Nugroho Eko
Published: June 2023

Background: Eating habits are formed from childhood and develop into adulthood. Unhealthy eating habits will persist into adulthood and can lead  to various diseases. Healthy eating and behaviour should be taught using  engaging tools. The study aims to pilot nutrition education using the game-based learning approach, implementing a specially designed learning board game entitled "Gastronot".

Methods: A mixed-method study was used in two stages. The first stage was an FGD with 14 informants and in-depth interviews with six informants to develop the game. The second stage was the game's development, and a pre and post-test were conducted on 88 children to evaluate the game—the study was conducted from August 2019 to July 2020.

Results: Results showed almost half the children (49%) never heard about Balanced Nutrition Diet Pyramid. There was a significant difference between respondents' knowledge before and after playing the game with a p-value of 0.021. The game was able to engage participants in the active learning process.

Conclusions: We concluded that the game-based learning utilizing the Gastronot board game demonstrated good results as a method for teaching primary school students about food and healthy eating habits.
Hesitancy towards the COVID-19 vaccine among health care practitioners in the Kingdom of Saudi Arabia: a cross-sectional study
Authors: Almojaibel Abdullah A. , Ansari Khalid , Alzahrani Yahya A. , Alessy Saleh A. , Farooqi Faraz A. , Alqurashi Yousef D.
Published: June 2023

Background: The coronavirus disease 2019 (COVID-19) pandemic is a major public health crisis worldwide. In less than 12 months since the World Health Organization declared the outbreak, several different COVID-19 vaccines have been approved and deployed mostly in developed countries since January 2021. However, hesitancy to accept the newly developed vaccines is a well-known public health challenge that needs to be addressed. The aim of this study was to measure willingness and hesitancy toward COVID-19 vaccines among health care practitioners' (HCPs) in Saudi Arabia.  

Methods: A cross-sectional study using an online self-reported survey was conducted among HCPs in Saudi Arabia between April 4th to April 25th 2021 using snowball sampling. Multivariate logistic regression was employed to identify the possible factors affecting HCPs’ willingness and hesitancy to receive COVID-19 vaccines.  

Results: Out of 776 participants who started the survey, 505 (65%) completed it and were included in the results. Among all HCPs, 47 (9.3%) either said “no” to receive the vaccine [20 (4%)] or were hesitant to receive it [27 (5.3%)]. Of the total number of the HCPs, 376 (74.5%) already received the COVID-19 vaccine, and 48 (9.50%) were registered to receive it. The main reason of agreement to receive the COVID-19 vaccine was “wanting to protect self and others from getting the infection” (24%).  

Conclusion: Our findings have shown that hesitancy toward receiving COVID-19 vaccines among HCPs in Saudi Arabia is limited and therefore may not be a serious issue. The outcomes of this study may help to understand factors that lead to vaccine hesitancy in Saudi Arabia and help public health authorities to design targeted health education interventions aiming to increase uptake of these vaccines.
Standard Operating Procedure for the analysis of trace elements in hydrothermal fluids by Inductively Coupled Plasma Mass Spectrometry (ICP-MS)
Authors: Correggia Monica , Di Iorio Luciano , Bastianoni Alessia Benedicta , Yücel Mustafa , Cordone Angelina , Giovannelli Donato
Published: June 2023

This standard operating procedure (SOP) validates an inductively coupled plasma mass spectrometry (ICP-MS) procedure for the trace element determinations in hydrothermal fluids. Hydrothermal fluids are aqueous solutions with a wide range of temperature, salinity, pH and trace elements that can be used by a set of microbial proteins containing redox-sensitive transition metals as their catalytic core. Due to the high variability of these samples, we have developed this protocol taking into account the special features of the matrices analyzed. An ICP-MS 7900 Agilent system was used. Calibration curves are linear in the 0.01 to 100 μg/L concentration range.
Interspecific competition affects spore germination and gametophore development of mosses
Authors: Cheng Jingmin , Lončarević Isidora , Cronberg Nils
Published: June 2023

Background:  Interactions between moss species in their earliest growth stages have received little attention. To what extent interspecific competition or priority effects influence spore germination, protonemal development and gametophore emergence is unknown. We evaluated such effects in pairwise interaction between six common bryophyte species: Atrichum undulatum, Bryum argenteum, Ceratodon purpureus, Funaria hygrometrica, Hypnum cupressiforme, Leptobryum pyriforme

Methods: Interspecific interactions were assessed in vitro. Spores were sterilized and sown on agar plates in three treatments: 1) as single species cultures (controls), 2) as pairwise species cultures inoculated simultaneously, and 3) with a time lag of 20 days between species. Data on the time needed for spore germination, germination rate, the time needed for gametophore differentiation, number of gametophores per germinated spore and average diameter of colonies were collected. We also performed spore germination tests in single-species cultures at the start and end of the study, as well as tests for density-dependency at spore germination and gametophore formation.

Results: We observed strong pairwise interactive effects when sowing spores of different species simultaneously or with a delay of 20 days. The results indicate that spore germination is often inhibited by interspecific competition. The first species has an advantage as compared to the later colonizing species, i.e., an apparent priority effect. Interspecific interactions were also evident during gametophore development and included both inhibition and facilitation.

Conclusion: We found pronounced differences in the relative performance of species in interaction with other species during spore germination and gametophore formation. Allelopathic effects are the most probable explanation for these observations. Our results under sterile lab conditions are likely to reflect processes that occur in the wild, governing biotic filtering and bryophyte community assembly during primary and secondary colonization.
A systematic review protocol for identifying the effectiveness of greenhouse gas mitigation interventions for health care systems in low- and middle-income countries
Authors: Blom Iris Martine , Asfura Javier Shafick , Eissa Mohamed , Mattijsen Juliette Claudine , Sana Hamaiyal , Haines Andrew , Whitmee Sarah
Published: June 2023

Background: Climate change is predicted to be our century's most significant health threat. In 2021, 46 countries committed to environmentally sustainable low carbon health care systems. Of those, 34 were from low- and middle-income countries (LMICs).  Currently, health systems are responsible for 4.4% of global greenhouse gas (GHG) emissions, with health systems in high-income countries (HICs) contributing the largest proportion to the sector's GHG emissions. However, future increases are predicted in LMICs in the absence of robust GHG mitigation. This systematic review aims to identify evidence-based GHG mitigation interventions to guide the transformation of health care systems towards net zero, specifically in LMICs. Additionally, potential synergies between interventions that aid adaption to climate change and mitigate GHG emissions will be investigated.

Methods: This protocol will follow the 'Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) checklist of recommended items to address in a systematic review protocol'. A comprehensive search will be conducted on electronic databases identified as relevant. Search terms were identified to capture all relevant peer-reviewed, primary research published between 1990 and 2022. The risk of bias will be assessed, and the quality of evidence graded. The eventual narrative synthesis will feed into a theory of change framework on GHG mitigation of health care systems in LMICs.

Discussion: This systematic review will synthesise the existing evidence around GHG mitigation interventions across all scopes of emissions, including scope 1 (health care operations), scope 2 (energy), and scope 3 (supply chains). It can be used to inform recommendations on how health care systems in LMICs can reduce emissions while prioritising which actions to take to gain the most significant reductions in GHG emissions, considering ease of implementation, scope and cost. Finally, this can catalyse further research in this area which is urgently needed.
Little’s Law and Educational Inequality: A Comparative Case Study of Teacher Workaround Productivity
Authors: Keppler Samantha M.
Published: June 2023

In this paper, we explore an employee workaround widespread in K–12 schools: compensating for insufficient funding with partnerships to nonprofit organizations (NPOs). We take an equity perspective and ask the following questions. (i) How do partnering workarounds differ across schools with different levels of socioeconomic advantage? (ii) What can education and NPO leaders do to ensure these workarounds do not exacerbate educational inequities? To answer these questions, we use Little’s Law: a school’s long-run average number of resource-supplementing partnerships (L) is a function of its average annual partnership formation rate (λ) and partnership cycle time (W). We collect and analyze interview (n = 62) and survey (n = 140) data from six strategically sampled schools with different levels of socioeconomic advantage to compare differences in λ and W and understand the implications for educational equity. We find wealthier schools have higher λ, making them more productive. We also find schools have equal W independent of wealth, but this problematically amplifies differences in λ. The difference in partnering productivity translates to educational inequities. We find that poorer schools report about 35% greater utility per partnership, but that is not enough to offset the disadvantage of fewer partnerships. Moreover, we find that differences in partnering productivity are particularly large for curricular partnerships, which are harder for poorer schools to form because of the high demand for wrap-around partnerships. Our findings contribute new knowledge on workarounds which supplement organizational resources and on the relationship between workarounds and equity.

This paper was accepted by Jay Swaminathan, operations management.

Funding: This work was supported by the National Science Foundation [Grant 1344266].

Supplemental Material: The data files and online appendix are available at https://doi.org/10.1287/mnsc.2023.4829 .
Shipment Consolidation with Multiple Shipping Methods Under Nonlinear Cost Structures
Authors: Xu Zhou , Li Feng , Chen Zhi-Long
Published: June 2023

We study a shipment consolidation problem commonly faced by companies that outsource logistics operations and operate in a commit-to-delivery mode. It involves delivering a given set of orders to their destinations by their committed due times using multiple shipping methods at the minimum total shipping and inventory cost. The shipping cost is generally nonlinear in shipping quantity and can be represented by a subadditive piecewise linear function. We investigate two shipping scenarios, one involving long-haul shipping only and the other involving joint long-haul and short-haul shipping. We develop analytical results and solution algorithms for the shipment consolidation problem under each shipping scenario. The problem under the first shipping scenario is shown to be strongly [Formula: see text]-hard. We find that a simple policy, called the First-Due-First-Delivered (FDFD) policy, which assigns orders with earlier delivery due times to shipping methods with earlier destination arrival times, is very effective. This policy enables us to develop a polynomial time algorithm, which not only solves the problem under the concave shipping cost structure optimally but also achieves a performance guarantee of 2 for the problem under the general subadditive shipping cost structure. For the problem under the second shipping scenario, we extend the FDFD policy for long-haul shipping and derive another policy, called the No-Wait policy, for short-haul shipping. We use these policies to develop a polynomial time algorithm and analyze its performance guarantee. Our computational experiments show that the algorithm significantly outperforms a commercial optimization solver, and its performance is robust across different parameter settings that reflect various practical situations.

This paper was accepted by Jeannette Song, operations management.

Supplemental Material: The data and e-companion are available at https://doi.org/10.1287/mnsc.2023.4835 .
Flexural Properties of Three-Ply Bolt-Laminated Pine Mats
Authors: Khademibami Laya , Ward Keith B. , Seale R. Daniel , Shmulsky Rubin , Ratcliff J. Tedrick
Published: June 2023

In the current study, three-ply bolt-laminated southern pine (Pinus sp.) 244 by 427 cm (8 by 14 ft) mats were evaluated. Mats were destructively tested in ⅓-point bending on a universal testing machine according to ASTM International standards. Twenty-eight unique specimens were destructively tested, and mean modulus of rupture (MOR) and modulus of elasticity (MOE) were calculated. According to the results both MOR and MOE values for the specimens were highly uniform. The mean MOR was 11.74 MPa (1,704 psi) and the mean MOE was 1,144 MPa (0.166 × 106 psi). Additionally, the values of parametric and nonparametric Fb (design fiber stress in bending values ) were reported as 4.05 MPa and 4.54 MPa (588 psi and 659 psi), respectively. The mechanical properties of these three-ply pine mats were also compared with other studies of mats from other species groups and design architectures.
Physical Properties of Pulp and Paper: A Comparison of Forming Procedures
Authors: Miao Yingju , Xiang Siyu , Wei Yingfen , Long Xiaohui , Qiu Jie , Miao Yingchun
Published: June 2023

In this work, we used the conventional wet papermaking process and the solution casting procedure to make paper sheets and optimized the relative content of eucalyptus and Simao pine pulps using the mechanical properties of the paper sheet as the evaluation index. The chemical composition, water retention value, zeta potential, carboxyl content, and drainage behavior of the pulp created using the optimal mass ratio for each method were measured, and the resulting paper sheets were characterized via Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and nitrogen adsorption/desorption isotherms. We found that for a ratio of eucalyptus to Simao pine pulps of 94:6 using the wet papermaking process, the mechanical properties of sheets took their optimal values, and the tear, tensile, and burst indexes and the folding endurance were equal to 4.43 mN·m2·g−1, 27.47 N·m·g−1, 1.13 kPa·m2·g−1, and 11.38 times, respectively, whereas the ratio leading to the best possible mechanical performance in the solution casting process was 88:12, and the corresponding paper sheets had tear, tensile, and burst indexes and the folding endurance of 11.73 mN·m2·g−1, 23.03 N·m·g−1, 0.68 kPa·m2·g−1, and 25.50 times, respectively. The cellulose, hemicellulose, and lignin contents of the pulp treated by the solution casting method were lower by 1.88, 3.11, and 2.67 percent, respectively, compared to that obtained via the wet papermaking process. However, the water retention value, zeta potential, and carboxyl content of the pulp obtained via solution casting were higher by 50.31, 123.41, and 50.15, percent, respectively, compared to that obtained via the wet papermaking process. The drainage time obtained via the solution casting method was one-fifth of that obtained via the wet forming process. The paper sheet prepared via the solution casting method was found to exhibit weaker hydrogen bonding, a decreased level of crystallinity (26.64% lower), and an increased compactness and N2 gas adsorption capacity (19.55% and 66.7% higher, respectively) compared to the sheet obtained via the wet papermaking process. This work shows that the physical properties of the paper prepared via the two processes considered here, using their respective optimal weight ratios of the different types of pulp, have their own advantages.
Understanding the timing and outcome of the Russian Revolution: a public choice approach
Authors: Dempster Gregory M. , Ekelund Robert B. , Thornton Mark
Published: June 2023

The October Revolution in Russia is better understood in light of Gordon Tullock’s by-product theory of revolution. This approach entails a focus on private costs and benefits rather than on public goods. It is shown that in terms of economic development, fiscal stability, and income distribution, that is, public goods, conditions in late-tsarist Russia were improving, not deteriorating, as the revolution approached. We reinterpret the impact of the many political concessions that followed the earlier Russian Revolution of 1905 and conclude that they had ultimately increased, rather than decreased, the probability of revolution. Finally, we show that various forms of foreign intervention (financial, military, and philosophical) made the unlikely Lenin the ultimate victor in the outcome of the Russian Revolution.
Co-phase errors sensing method for Golay3 telescope system via a transfer network
Authors: Li Jiawen , Wu Xiaoyan , Ma Xiugang , Qian Junhong , Liu Hewei , Zhang Wenbo , Yang Xiaomin , Tao Ye , Zhang Rongzhu
Published: June 2023

Optical sparse-aperture systems face severe challenges, including
detecting and correcting co-phase errors. In this study, a search
framework based on fine tuning a pre-trained network is proposed to
analyze the co-phase errors of a Golay3 telescope system. Based on
this, an error compensation control system is established. First, a
hash-like binary code is created by fine-tuning the pre-trained model.
Secondly, a pre-trained network is used to extract the deep features
of the image, and an index database is built between the image
features and the corresponding co-phase error values. Finally, the Top
1-ranked features and corresponding co-phase error values are returned
through the hash-like binary code hierarchical deep search database to
provide driving data for the error correction system. Numerical
simulations and experimental results verify the method’s validity. The
experimental results show that the correction system works well when
the dynamic piston is [−5,5]λ, and the tilt error range is [−15,15]µrad. Compared with existing detection
methods, this method does not require additional optical components,
has a high correction accuracy, and requires a short training time.
Furthermore, it can be used to detect piston and tilt errors
simultaneously.
Electromagnetically actuated 3D-printed tunable optical slit device
Authors: Erdil Kuter , Gürcüoğlu Oğuz , Ferhanoğlu Onur
Published: June 2023

This paper presents the design, manufacturing, and characterization of a three-dimensional (3D)-printed and electromagnetically actuated adjustable optical slit structure. The device comprises magnet-attached slits connected to the main frame via two springs controlled by external coils. To analyze the forces acting on the springs and simulate the mechanical behavior of the device, we developed both analytical and finite-element models. After fabricating the device using fused deposition, we conducted a series of tests to evaluate its performance. These tests included (1) analyzing the opacity of the slit blade as a function of its thickness, (2) measuring the temperature increase resulting from the power applied to the coils to determine the operable range of the structure, and (3) evaluating the hysteresis, repeatability, and resolution (minimum step) of the device. The experimental works were crucial to assessing the device’s practicality and optimizing its performance for specific applications, which reveals a maximum slit width of ∼450µm, with ∼6.4µm step size within this study. Overall, our developed slit device has the potential to be useful in various optics-related laboratories due to its compatibility with conventional 1-inch (25.4 mm) diameter optomechanical mounts, compact form, low power consumption, and rapid prototyping capability with hybrid materials in a cost-friendly fashion, owing to the 3D-printing technology. We discuss an application where the adjustable slit is employed in a combined laser-scanning microscope and a spectrometer, highlighting its versatility and potential for the future.
Role of pixel design and emission wavelength on the light extraction of nitride-based micro-LEDs
Authors: Vögl Florian , Avramescu Adrian , Knorr Fabian , Lex Andreas , Waag Andreas , Hetzl Martin , von Malm Norwin
Published: June 2023

Micro-light emitting diodes (µ-LEDs) suffer from a drastic drop in internal quantum efficiency that emerges with the miniaturization of pixels down to the single micrometer size regime. In addition, the light extraction efficiency (LEE) and far field characteristics change significantly as the pixel size approaches the wavelength of the emitted light. In this work, we systematically investigate the fundamental optical properties of nitride-based µ-LEDs with the focus on pixel sizes from 1 µm to 5 µm and various pixel sidewall angles from 0∘ to 60∘ using finite-difference time-domain simulations. We find that the LEE strictly increases with decreasing pixel size, resulting in a LEE improvement of up to 45% for a 1 µm pixel compared to a 20 µm pixel. The ideal pixel sidewall angle varies between 35∘ and 40∘, leading to a factor of 1.4 enhancement with respect to vertical pixel sidewalls. For pixel sizes in the order of 2 µm and smaller, a substantial transition of far field properties can be observed. Here, the far field shape depends severely on the pixel sidewall angle and affects the LEE within a solid angle of ±15∘. Moreover, we investigate the impact of emission wavelength and observe major differences in optical characteristics for blue, green and red emitting pixels, which is relevant for real-world applications. Finally, we discuss the implications of the assumptions we made and their significance for the design of µ-LEDs.
C-DONN: compact diffractive optical neural network with deep learning regression
Authors: Liu Wencan , Fu Tingzhao , Huang Yuyao , Sun Run , Yang Sigang , Chen Hongwei
Published: June 2023

A new method to improve the integration level of an on-chip diffractive optical neural network (DONN) is proposed based on a standard silicon-on-insulator (SOI) platform. The metaline, which represents a hidden layer in the integrated on-chip DONN, is composed of subwavelength silica slots, providing a large computation capacity. However, the physical propagation process of light in the subwavelength metalinses generally requires an approximate characterization using slot groups and extra length between adjacent layers, which limits further improvements of the integration of on-chip DONN. In this work, a deep mapping regression model (DMRM) is proposed to characterize the process of light propagation in the metalines. This method improves the integration level of on-chip DONN to over 60,000 and elimnates the need for approximate conditions. Based on this theory, a compact-DONN (C-DONN) is exploited and benchmarked on the Iris plants dataset to verify the performance, yielding a testing accuracy of 93.3%. This method provides a potential solution for future large-scale on-chip integration.
Reversibly reconfigurable GSST metasurface for broadband beam steering and achromatic focusing in the long-wave infrared
Authors: Pan Meiyan , Fu Yifei , Zang Yujia , Zheng Mengjie , Chen Hao , He Xinyi , Lu Yanxin , Chen Yihang
Published: June 2023

Active optical metasurfaces promise compact, lightweight, and energy-efficient optical systems with unprecedented performance. Chalcogenide phase-change material Ge2Sb2Se4Te1 (GSST) has shown tremendous advantages in the design of mid-infrared active metasurfaces. However, most of the GSST-based active metasurfaces can only work efficiently within a narrow frequency range. Furthermore, their design flexibility and reversible switching capability are severely restricted by the melting of GSST during re-amorphization. Here, we propose broadband, reversibly tunable, GSST-based transmissive metasurfaces operating in the long-wave infrared spectrum, where the GSST micro-rods are cladded by refractory materials. To accurately evaluate the performance of the proposed metasurfaces, two figures of merits are defined: FOMΦ for the evaluation of wavefront matching, and FOMop for the assessment of the overall performance incorporating both wavefront modulation efficiency and switching contrast ratio. For the proof of concept, two meta-devices are numerically presented: a multifunctional deflector that offers continuous beam steering and long-wave pass filtering simultaneously, and a large-area (1 cm × 1 cm) broadband (11-14 µm) varifocal metalens with the ability of achromatic imaging (12.5-13.5 µm). In particular, the metalens features high FOMop values over 16 dB in the achromatic band, with the average focusing efficiency approximating 70% (60%) in amorphous (crystalline) state and a spectral switching contrast ratio surpassing 25 dB. Our design scheme provides an additional degree of freedom for dynamic modulation and offers a novel approach for achieving high-efficiency mid-infrared compact optical devices.
Complete characterization of a Yb-based OPA at a high repetition rate using frequency resolved optical switching
Authors: Haddad Elissa , Longa Adrien , Lassonde Philippe , Leblanc Adrien , Ibrahim Heide , Boschini Fabio , Légaré François , Jargot Gaëtan
Published: June 2023

We demonstrate experimentally that frequency resolved optical switching (FROSt) can be used to characterize ultra-broadband pulses at high repetition rates up to 500 kHz. Specifically, we present the complete temporal characterization of an optical parametric amplifier (OPA), from the supercontinuum (SC) to the second stage of amplification. Simultaneous characterization of co-propagating signal and idler pulses enables retrieval of their group delay, as well as their temporal phase and intensity. Our study focuses on an extensive frequency range spanning the infrared region (1.2 to 2.4 µm) and confirms the strength and convenience of FROSt as a single tool for characterizing a wide range of pulses at high repetition rates.
Simultaneous sensing of temperature and strain with enhanced performance using forward Brillouin scattering in highly nonlinear fiber
Authors: Yang Guijiang , Zeng Keyan , Wang Liang , Tang Ming , Liu Deming
Published: June 2023

Simultaneous temperature and strain sensing has been demonstrated for the first time to our knowledge by using forward Brillouin scattering (FBS) in a highly nonlinear fiber (HNLF). It is based on different responses of radial acoustic modes R0,
m
and torsional-radial acoustic modes TR2,
m
to the temperature and strain. High-order acoustic modes with large FBS gain in an HNLF are chosen to improve the sensitivity. To reduce the measurement error, a method to select the best mode combination with the lowest measurement errors is proposed and demonstrated by both simulation and experiment. Three mode combinations have been used for both temperature and strain sensing, and by using the mode combination (R0,18, TR2,29), the lowest temperature and strain errors of 0.12°C/39 µɛ have been achieved. Compared with sensors using backward Brillouin scattering (BBS), the proposed scheme only requires frequency measurement around 1 GHz, which is cost-effective without the need for a ∼10-GHz microwave source. Moreover, the accuracy is enhanced since the FBS resonance frequency and spectrum linewidth are much smaller than those of BBS.
Two-state lasing in a quantum dot racetrack microlaser
Authors: Makhov Ivan , Ivanov Konstantin , Moiseev Eduard , Dragunova Anna , Fominykh Nikita , Kryzhanovskaya Natalia , Zhukov Alexey
Published: June 2023

The peculiarities of two-state lasing in a racetrack microlaser with an InAs/GaAs quantum dot active region are investigated by measuring the electroluminescence spectra at various injection currents and temperatures. Unlike edge-emitting and microdisk lasers, where two-state lasing involves the ground and first excited-state optical transitions of quantum dots, in racetrack microlasers, we observe lasing through the ground and second excited states. As a result, the spectral separation between lasing bands is doubled to more than 150 nm. A temperature dependence of threshold currents for lasing via ground and second excited states of quantum dots was also obtained.
Vortex solitons in moiré optical lattices
Authors: Ivanov Sergey K. , Konotop Vladimir V. , Kartashov Yaroslav V. , Torner Lluís
Published: June 2023

We show that optical moiré lattices enable the existence of vortex solitons of different types in self-focusing Kerr media. We address the properties of such states both in lattices having commensurate and incommensurate geometries (i.e., constructed with Pythagorean and non-Pythagorean twist angles, respectively), in the different regimes that occur below and above the localization-delocalization transition. We find that the threshold power required for the formation of vortex solitons strongly depends on the twist angle and, also, that the families of solitons exhibit intervals where their power is a nearly linear function of the propagation constant and they exhibit a strong stability. Also, in the incommensurate phase above the localization–delocalization transition, we found stable embedded vortex solitons whose propagation constants belong to the linear spectral domain of the system.
Optimal density of bacterial cells
Authors: Pang Tin Yau , Lercher Martin J.
Published: June 2023

A substantial fraction of the bacterial cytosol is occupied by catalysts and their substrates. While a higher volume density of catalysts and substrates might boost biochemical fluxes, the resulting molecular crowding can slow down diffusion, perturb the reactions’ Gibbs free energies, and reduce the catalytic efficiency of proteins. Due to these tradeoffs, dry mass density likely possesses an optimum that facilitates maximal cellular growth and that is interdependent on the cytosolic molecule size distribution. Here, we analyze the balanced growth of a model cell, accounting systematically for crowding effects on reaction kinetics. Its optimal cytosolic volume occupancy depends on the nutrient-dependent resource allocation into large ribosomal vs. small metabolic macromolecules, reflecting a tradeoff between the saturation of metabolic enzymes, favoring larger occupancies with higher encounter rates, and the inhibition of the ribosomes, favoring lower occupancies with unhindered diffusion of tRNAs. Our predictions across growth rates are quantitatively consistent with the experimentally observed reduction in volume occupancy on rich media compared to minimal media in E. coli. Strong deviations from optimal cytosolic occupancy only lead to minute reductions in growth rate, which are nevertheless evolutionarily relevant due to large bacterial population sizes. In sum, cytosolic density variation in bacterial cells appears to be consistent with an optimality principle of cellular efficiency.
Network analysis of scientific advisory committee integration in climate change policy: A comparison of Germany and Japan
Authors: Nagel Melanie , Satoh Keiichi , Henry Adam Douglas
Published: June 2023

According to the literature on Environmental Policy Integration (EPI), decisionmaking in complex domains of environmental policy—of which climate change is a prime example—tend to fragment and silo into individual dimensions of a problem. Scientific Advisory Committees (SACs) have been widely used to promote more integrated decisionmaking. SACs are intended to integrate the varied, and often fragmented, dimensions of policy problems, and this integration is widely believed to enable more effective use of science in climate change policy. This paper empirically evaluates the degree of integration achieved through SACs in two national climate policy contexts: Germany and Japan. Network analysis is used to examine the myriad scientific advisory committees focused on climate change policy in these nations (N = 218), and quantify the degree of vertical integration (integration among different sectors) and horizontal integration (integration among different governmental bodies). Results show greater vertical integration among German SACs than Japanese SACs, and similar levels of horizontal integration between the two nations despite having very different structures. Such efforts to empirically connect the conceptual discussion of integration in EPI with empirical observations of integration in actual climate policy processes is an important step towards understanding the strategies that may be used to promote more integrated decisionmaking in climate change policy.
Retrotransposon LINE-1 bodies in the cytoplasm of piRNA-deficient mouse spermatocytes: Ribonucleoproteins overcoming the integrated stress response
Authors: De Luca Chiara , Gupta Anuj , Bortvin Alex
Published: June 2023

Transposable elements (TE) are mobile DNA sequences whose excessive proliferation endangers the host. Although animals have evolved robust TE-targeting defenses, including Piwi-interacting (pi)RNAs, retrotransposon LINE-1 (L1) still thrives in humans and mice. To gain insights into L1 endurance, we characterized L1 Bodies (LBs) and ORF1p complexes in germ cells of piRNA-deficient Maelstrom null mice. We report that ORF1p interacts with TE RNAs, genic mRNAs, and stress granule proteins, consistent with earlier studies. We also show that ORF1p associates with the CCR4-NOT deadenylation complex and PRKRA, a Protein Kinase R factor. Despite ORF1p interactions with these negative regulators of RNA expression, the stability and translation of LB-localized mRNAs remain unchanged. To scrutinize these findings, we studied the effects of PRKRA on L1 in cultured cells and showed that it elevates ORF1p levels and L1 retrotransposition. These results suggest that ORF1p-driven condensates promote L1 propagation, without affecting the metabolism of endogenous RNAs.
Exploring the ethics of political PR professionals using moral foundations theory
Authors: Mikhaylova Oxana , Abramov Roman
Published: June 2023

This paper offers a multidimensional theoretical scheme to analyze professional ethics in the field of political public relations. We suggest investigating the decisions of these professionals using moral foundations theory because human ethical reasoning is contextual, and the examination of ethics in a one-dimensional manner as previous researchers have done overlooks the complexity of the moral choices that such professionals make. The prospects of the proposed theoretical approach are demonstrated on 16 interviews with post-soviet Russian political PR industry leaders that were conducted from March 2018 to April 2020. Our empirical findings show that Russian political PR specialists employ all moral foundations, however, in their narratives the “care/harm” and “authority/respect” foundations were not mentioned very often. Overall, this paper makes a critical contribution to research on professional ethics in political public relations, and it provides important insight into the specifics of moral reasoning in the Russian political PR industry that is insufficiently described in the current literature.
The effects of factors on the motivations for knowledge sharing in online health communities: A benefit-cost perspective
Authors: Wu Pei , Zhang Runtong , Luan Jing
Published: June 2023

Online health communities (OHCs) provide knowledge for users, enabling conversations across a broad range of health topics. The development of OHCs depends on users’ motivations to share health knowledge. Yet little literature has explored how perceived benefits and costs affect users’ motivations for sharing both general and specific knowledge. Based on social exchange theory, we propose a research model that comprises intrinsic benefits (sense of self-worth, satisfaction), extrinsic benefits (social support, reputation, and online attention), cognitive cost, and executional cost to investigate the effects of these factors on users’ motivations for general and specific knowledge sharing. We compare the different effects of these factors on users’ motivations for knowledge sharing. Results demonstrate positive effects of intrinsic and extrinsic benefits on users’ motivations for general and specific knowledge sharing. Differences exist in the negative effects of cognitive and executional costs on users’ motivations for general and specific knowledge sharing. This study contributes to promoting the enrichment of online health knowledge and provides implications for the development of OHCs.
The order of sequential exposure of U2OS cells to gamma and alpha radiation influences the formation and decay dynamics of NBS1 foci
Authors: Tartas Adrianna , Lundholm Lovisa , Scherthan Harry , Wojcik Andrzej , Brzozowska Beata
Published: June 2023

DNA double strand breaks (DSBs) are a deleterious form of DNA damage. Densely ionising alpha radiation predominantly induces complex DSBs and sparsely ionising gamma radiation—simple DSBs. We have shown that alphas and gammas, when applied simultaneously, interact in producing a higher DNA damage response (DDR) than predicted by additivity. The mechanisms of the interaction remain obscure. The present study aimed at testing whether the sequence of exposure to alphas and gammas has an impact on the DDR, visualised by live NBS1-GFP (green fluorescent protein) focus dynamics in U2OS cells. Focus formation, decay, intensity and mobility were analysed up to 5 h post exposure. Focus frequencies directly after sequential alpha → gamma and gamma → alpha exposure were similar to gamma alone, but gamma → alpha foci quickly declined below the expected values. Focus intensities and areas following alpha alone and alpha → gamma were larger than after gamma alone and gamma → alpha. Focus movement was most strongly attenuated by alpha → gamma. Overall, sequential alpha → gamma exposure induced the strongest change in characteristics and dynamics of NBS1-GFP foci. Possible explanation is that activation of the DDR is stronger when alpha-induced DNA damage precedes gamma-induced DNA damage.
Does monocarpic Phyllostachys nigra var. henonis regenerate after flowering in Japan? Insights from 3 years of observation after flowering
Authors: Yamada Toshihiro , Imada Karin , Aoyagi Hitoshi , Nakabayashi Miyabi
Published: June 2023

Phyllostachys nigra var. henonis, a monocarpic bamboo with a 120-year flowering interval, is next predicted to flower in Japan in the 2020s. Because a huge area of the country is presently covered by stands of this species, post-flowering dieback of these stands and ensuing drastic changes in land cover may cause serious social and/or environmental problems. No study on the regeneration of this bamboo species was conducted during the last flowering event in the 1900s, and the regeneration process of this species is thus still unknown. In 2020, we encountered a localized flowering of P. nigra var. henonis in Japan and used this discovery as a rare opportunity to study the initial regeneration process of the species. Over 3 years, more than 80% of culms in the study site bloomed, but no seed was produced. In addition, no established seedlings were located. These facts strongly suggest that P. nigra var. henonis lacks the ability to produce seeds and cannot undergo sexual regeneration. Some bamboo culms were produced after flowering but died within 1 year of emergence. Small, weak culms (dwarf ramets) also appeared after flowering, but most died within 1 year as well. Three years after flowering, all culms had died, with no sign of regeneration detected. According to our 3 years of observation, this bamboo appears to be hard to regenerate—an idea completely contradicted by the fact that this species has long persisted in Japan. We thus considered other possible regeneration modes for P. nigra var. henonis.
Effects of a short period of postural training on postural stability and vestibulospinal reflexes
Authors: Grasso Claudia , Barresi Massimo , Tramonti Fantozzi Maria Paola , Lazzerini Francesco , Bruschini Luca , Berrettini Stefano , Andre Paolo , Dolciotti Cristina , De Cicco Vincenzo , De Cicco Davide , d’Ascanio Paola , Orsini Paolo , Montanari Francesco , Faraguna Ugo , Manzoni Diego
Published: June 2023

The effects of postural training on postural stability and vestibulospinal reflexes (VSRs) were investigated in normal subjects. A period (23 minutes) of repeated episodes (n = 10, 50 seconds) of unipedal stance elicited a progressive reduction of the area covered by centre of pressure (CoP) displacement, of average CoP displacement along the X and Y axes and of CoP velocity observed in this challenging postural task. All these changes were correlated to each other with the only exception of those in X and Y CoP displacement. Moreover, they were larger in the subjects showing higher initial instability in unipedal stance, suggesting that they were triggered by the modulation of sensory afferents signalling body sway. No changes in bipedal stance occurred soon and 1 hour after this period of postural training, while a reduction of CoP displacement was apparent after 24 hours, possibly due to a beneficial effect of overnight sleep on postural learning. The same period of postural training also reduced the CoP displacement elicited by electrical vestibular stimulation (EVS) along the X axis up to 24 hours following the training end. No significant changes in postural parameters of bipedal stance and VSRs could be observed in control experiments where subjects were tested at identical time points without performing the postural training. Therefore, postural training led to a stricter control of CoP displacement, possibly acting through the cerebellum by enhancing feedforward mechanisms of postural stability and by depressing the VSR, the most important reflex mechanism involved in balance maintenance under challenging conditions.
Symptomatic malaria enhances protection from reinfection with homologous Plasmodium falciparum parasites
Authors: Markwalter Christine F. , Petersen Jens E. V. , Zeno Erica E. , Sumner Kelsey M. , Freedman Elizabeth , Mangeni Judith N. , Abel Lucy , Obala Andrew A. , Prudhomme-O’Meara Wendy , Taylor Steve M.
Published: June 2023

A signature remains elusive of naturally-acquired immunity againstPlasmodium falciparum. We identifiedP.falciparumin a 14-month cohort of 239 people in Kenya, genotyped at immunogenic parasite targets expressed in the pre-erythrocytic (circumsporozoite protein, CSP) and blood (apical membrane antigen 1, AMA-1) stages, and classified into epitope type based on variants in the DV10, Th2R, and Th3R epitopes in CSP and the c1L region of AMA-1. Compared to asymptomatic index infections, symptomatic malaria was associated with reduced reinfection by parasites bearing homologous CSP-Th2R (adjusted hazard ratio [aHR]:0.63; 95% CI:0.45–0.89; p = 0.008) CSP-Th3R (aHR:0.71; 95% CI:0.52–0.97; p = 0.033), and AMA-1 c1L (aHR:0.63; 95% CI:0.43–0.94; p = 0.022) epitope types. The association of symptomatic malaria with reduced hazard of homologous reinfection was strongest for rare epitope types. Symptomatic malaria provides more durable protection against reinfection with parasites bearing homologous epitope types. The phenotype represents a legible molecular epidemiologic signature of naturally-acquired immunity by which to identify new antigen targets.