bluuebunny/crossref_metadata_2025 huggingface dataset:
Hit the gym or hit the hay: can evening exercise characteristics predict compromised sleep in healthy adults?
Authors: Miller Dean J. , Roach Gregory D. , Lastella Michele , Capodilupo Emily R. , Sargent Charli
Published: July 2023

Introduction: Recent sleep guidelines regarding evening exercise have shifted from a conservative (i.e., do not exercise in the evening) to a more nuanced approach (i.e., exercise may not be detrimental to sleep in circumstances). With the increasing popularity of wearable technology, information regarding exercise and sleep are readily available to the general public. There is potential for these data to aid sleep recommendations within and across different population cohorts. Therefore, the aim of this study was to examine if sleep, exercise, and individual characteristics can be used to predict whether evening exercise will compromise sleep.

Methods: Data regarding evening exercise and the subsequent night’s sleep were obtained from 5,250 participants (1,321F, 3,929M, aged 30.1 ± 5.2 yrs) using a wearable device (WHOOP 3.0). Data for females and males were analysed separately. The female and male datasets were both randomly split into subsets of training and testing data (training:testing = 75:25). Algorithms were trained to identify compromised sleep (i.e., sleep efficiency <90%) for females and males based on factors including the intensity, duration and timing of evening exercise.

Results: When subsequently evaluated using the independent testing datasets, the algorithms had sensitivity for compromised sleep of 87% for females and 90% for males, specificity of 29% for females and 20% for males, positive predictive value of 32% for females and 36% for males, and negative predictive value of 85% for females and 79% for males. If these results generalise, applying the current algorithms would allow females to exercise on ~ 25% of evenings with ~ 15% of those sleeps being compromised and allow males to exercise on ~ 17% of evenings with ~ 21% of those sleeps being compromised.

Discussion: The main finding of this study was that the models were able to predict a high percentage of nights with compromised sleep based on individual characteristics, exercise characteristics and habitual sleep characteristics. If the benefits of exercising in the evening outweigh the costs of compromising sleep on some of the nights when exercise is undertaken, then the application of the current algorithms could be considered a viable alternative to generalised sleep hygiene guidelines.
The known, unknown, and the intriguing about members of a critically endangered traditional medicinal plant genus Aconitum
Authors: Kakkar Richa Ashok , Haneen Mariam Azeezuddin , Parida Akash Chandra , Sharma Gaurav
Published: July 2023

Humanity will always be indebted to plants. In the ongoing scientific era, the ‘Herbal Revolution’ has helped discover several valuable medicinal plants and associated novel secondary metabolites from the diverse unexplored ecosystems, treating several diseases via phytotherapy. The Aconitum genus comprises several economically-important poisonous mountainous medicinal plant species whose unique biodiversity is on the verge of extinction due to illegal human intervention triggered habitat loss, over-harvesting, and unrestricted trading. Owing to its vast diversity of diterpene alkaloids, most species are extensively used to treat several ailments in rural parts of the world. Irrespective of this, many unexplored and intriguing prospects exist to understand and utilize this critical plant for human benefit. This systematic review tries to fill this gap by compiling information from the sporadically available literature known for ~300 Aconitum spp. regarding its nomenclature and classification, endangerment, plant morphology, ploidy, secondary metabolites, drug pharmacokinetics, conservation, and omics-based computational studies. We also depicted the disparity in the studied model organisms for this diverse genus. The absence of genomic/metagenomic data is becoming a limiting factor in understanding its plant physiology, metabolic pathways, and plant-microbes interactions, and therefore must be promoted. Additionally, government support and public participation are crucial in establishing conservation protocols to save this plant from endangerment.
Fabrication of Carum copticum essential oil–loaded chitosan nanoparticles and evaluation its insecticidal activity for controlling Rhyzopertha dominica and Tribolium confusum
Authors: Ziaee Masumeh , Sheikhzadeh Takabi Asiyeh , Ebadollahi Asgar
Published: July 2023

Introduction

Plant essential oils (EOs) can be used as a feasible tool for insect pest control. Nanoparticle formulations of plant EOs can improve the efficiency and stability of EOs, as well as insecticidal potential.

Methods

In this study, Carum copticum L. essential oil–loaded nanoparticles (OLNs) were prepared via an oil-in-water emulsion, followed by droplet solidiffication via ionic gelation using a cross-linker, sodium tripolyphosphate (TPP). The nanoparticles were characterized by ultraviolet and visible (UV–Vis) spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), laser light scattering (LS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Moreover, the insecticidal activity of C. copticum EO and OLNs was evaluated against Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) and Tribolium confusum Jacquelin du Val. (Coleoptera: Tenebrionidae). In addition, their effectiveness was assessed on the progeny production of tested insect species.

Results and discussion

The loading efficiency ranged from 34.33 to 84.16% when the chitosan to EO weight ratio was 1:1.25 and 1:0.5, respectively. The loading efficiency decreased with increasing EO content in the nanoparticles. The OLN particles exhibited spherical shape. The particle size was in the range 120–223.6 nm and increased with the increase of EO to chitosan ratio. So that the largest mean particle size (223.6 nm) was reported in the 1:1.25 weight ratio of chitosan to the EO. The mortality percentage of R. dominica and T. confusum adults were 74 and 57% when exposed for 7 days to 2000 mg/kg of OLNs at the 1:1.25 weight ratio, while EO caused 62 and 44% mortality on both insect species, respectively. Therefore, OLNs can potentially improve the insecticidal activity of C. copticum EO and could be applied to facilitate control of stored-product insect pests.
An effective method for establishing a regeneration and genetic transformation system for Actinidia arguta
Authors: Yao Wantian , Kong Lingling , Lei Diya , Zhao Bing , Tang Honglan , Zhou Xuan , Lin Yuanxiu , Zhang Yunting , Wang Yan , He Wen , Li Mengyao , Chen Qing , Luo Ya , Wang Xiaorong , Tang Haoru , Zhang Yong
Published: July 2023

The all-red A. arguta (Actinidia arguta) is an anthocyanin-rich and excellent hardy fruit. Many studies have focused on the green-fleshed A. arguta, and fewer studies have been conducted on the all-red A. arguta. Here we reported a regeneration and Agrobacterium-mediated transformation protocol by using leaves of all-red A. arguta as explants. Aseptic seedling leaves of A. arguta were used as callus-inducing materials. MS medium supplemented with 0.3 mg·L-1 2,4-D and 1.0 mg·L-1 BA was the optimal medium for callus induction of leaves, and medium supplemented with 3 mg·L-1 tZ and 0.5 mg·L-1 IAA was optimal for adventitious shoot regeneration. The best proliferation medium for adventitious buds was MS + 1.0 mg·L-1 BA + 0.3 mg·L-1 NAA. The best rooting medium was 1/2MS + 0.7 mg·L-1 IBA with a 100% rooting rate. For the red flesh hardy kiwi variety ‘Purpurna Saduwa’ (A. arguta var. purpurea), leaves are receptors for Agrobacterium (EHA105)-mediated transformation. The orthogonal experiment was used for the optimization of each genetic transformation parameter and the genetic transformation of the leaves was 21% under optimal conditions. Our study provides technical parameters for applying genetic resources and molecular breeding of kiwifruit with red flesh.
Review of recent advances in post-harvest techniques for tropical cut flowers and future prospects: Heliconia as a case-study
Authors: Malakar Moumita , Paiva Patrícia Duarte de Oliveira , Beruto Margherita , Cunha Neto Antonio Rodrigues da
Published: July 2023

Aesthetic attributes and easy-to-grow nature of tropical cut flowers (TCFs) have contributedto their potential for increased production. The dearth of information regarding agronomic practices and lack of planting materials are the key hindrances against their fast expansion. Unconventional high-temperature storage requirements and the anatomy of the peduncle contribute topoor vase life performance, while troublesome packaging and transport due to unusual size and structureprimarily cause post-harvest quality deterioration. Nonetheless, the exotic floral structuresconsequently increase market demand, particularly in temperate countries. This boosts studies aimed at overcoming post-harvest hindrances. While a few TCFs (Anthurium, Strelitzia, Alpinia, and a few orchids) are under the spotlight, many others remain behind the veil.Heliconia, an emerging specialty TCF (False Bird-of-Paradise, family Heliconiaceae), is one of them. The structural uniquenessand dazzling hues ofHeliconiagenotypes facilitate shifting its position from the back to the forefrontof the world floriculture trade. The unsatisfactory state-of-the-art ofHeliconiaresearch and the absence of any review exclusively on it are the key impetus for structuring this review. In addition to the aforementioned setbacks, impaired water uptake capacity after harvest, high chilling sensitivity, and the proneness of xylem ducts to microbial occlusion may be counted as a few additional factors that hinder its commercialization. This review demonstrates the state-of-the-art of post-harvest research while also conceptualizing the implementation of advanced biotechnological aid to alleviate the challenges, primarily focusing onHeliconia(the model crop here) along with some relevant literature on its other allied members. Standard harvesting indices, grading, and packaging are also part of the entire post-harvest operational chain, but since these phases are barely considered inHeliconiaand the majority of tropical ornamentals except a few, a comprehensive account of these aspects has also been given. The hypothesized cues to nip chilling injury, resorting to different bio-chemical treatments, nano-based technology, and advanced packaging techniques, may help overcome preservation difficulties and propel its transition from niche to the commercial flower market. In a nutshell, readers will gain a comprehensive overview of how optimum post-harvest handling practices can rewardingly characterize this unique group of TCFs as the most remunerative component.
Expanding research on the impact of financial hardship on emotional well-being: guidance of diverse stakeholders to the Emotional Well-Being and Economic Burden of Disease (EMOT-ECON) Research Network
Authors: Pisu Maria , Liang Margaret I. , Pressman Sarah D. , Ryff Carol D. , Patel Minal R. , Hussein Mustafa , Williams Courtney P. , Henrikson Nora B. , Schoenberger Yu-Mei , Pracht Laurel J. , Bradshaw Erin , Carpenter Terrell Terri , Matthis Amy , Schwartz David L. , Martin Michelle Y.
Published: July 2023

The Emotional Well-Being and Economic Burden (EMOT-ECON) Research Network is one of six research networks funded by the National Institutes of Health (NIH) to advance research about emotional well-being (EWB), and the only one that focuses on addressing how economic burden due to disease or illness affects EWB. The network convened researchers, patients, patient advocates, health care providers and other stakeholders from across the US to discuss the significance of addressing the impact of the economic burden of disease on EWB, the complexity of this prevalent problem for patients and families, and the research gaps that still need to be studied to ultimately develop strategies to reduce the impact of economic burden of disease on EWB and health. Participants identified some important future areas of research as those investigating: (i) prevalent and relevant emotions for patients experiencing economic burden of disease and financial hardship, and how their broader outlook on life is impacted; (ii) constructs and contexts that influence whether the economic burden is stressful; (iii) strategies to deal and cope and their positive or negative effects on EWB and health; and (iv) multi-level and multi-stakeholder interventions to address economic factors (e.g., costs, ability to pay), administrative burdens, education and training, and especially patients’ emotional as well as financial status.
Quantifying the efficacy of an automated facial coding software using videos of parents
Authors: Burgess R. , Culpin I. , Costantini I. , Bould H. , Nabney I. , Pearson R. M.
Published: July 2023

Introduction

This work explores the use of an automated facial coding software - FaceReader - as an alternative and/or complementary method to manual coding.

Methods

We used videos of parents (fathers, n = 36; mothers, n = 29) taken from the Avon Longitudinal Study of Parents and Children. The videos—obtained during real-life parent-infant interactions in the home—were coded both manually (using an existing coding scheme) and by FaceReader. We established a correspondence between the manual and automated coding categories - namely Positive, Neutral, Negative, and Surprise - before contingency tables were employed to examine the software’s detection rate and quantify the agreement between manual and automated coding. By employing binary logistic regression, we examined the predictive potential of FaceReader outputs in determining manually classified facial expressions. An interaction term was used to investigate the impact of gender on our models, seeking to estimate its influence on the predictive accuracy.

Results

We found that the automated facial detection rate was low (25.2% for fathers, 24.6% for mothers) compared to manual coding, and discuss some potential explanations for this (e.g., poor lighting and facial occlusion). Our logistic regression analyses found that Surprise and Positive expressions had strong predictive capabilities, whilst Negative expressions performed poorly. Mothers’ faces were more important for predicting Positive and Neutral expressions, whilst fathers’ faces were more important in predicting Negative and Surprise expressions.

Discussion

We discuss the implications of our findings in the context of future automated facial coding studies, and we emphasise the need to consider gender-specific influences in automated facial coding research.
Exploring the relationship between multiple dimensions of subjective socioeconomic status and self-reported physical and mental health: the mediating role of affect
Authors: Kraft Pål , Kraft Brage
Published: July 2023

Introduction

This study aimed to investigate the predictive effects of two types of subjective socioeconomic status on self-reported physical and mental health. Specifically, we examined the MacArthur Scale (MacArthur) which measures perceived socioeconomic rank in the society and a novel scale called ComSim, which assessed how participants compared themselves socioeconomically to others coming from a similar socioeconomic background. We also considered the influence of income, education, and personal relative deprivation (PRD) in these analyses. Additionally, we explored whether these effects were mediated through negative and positive affect.

Methods

The data were collected through a cross-sectional, two-wave survey of 294 women and 294 men, with a mean age 41.6 years. Participants were recruited via an online platform.

Results

The results from multivariate regression models revealed that socioeconomic status measured with both the MacArthur Scale and ComSim significantly predicted both self-reported health measures, whereas income and education did not predict any of these measures in the full multivariate models. PRD only predicted self-reported mental health. Mediation analyses showed that negative and positive affect mediated the relationships between socioeconomic status measured by ComSim and self-reported health measures.

Discussion

These findings are discussed in the context of the similarity hypothesis of social comparison theory. The results underscore the importance of considering multiple dimensions when examining socioeconomic health disparities.
Characterization of superspreaders movement in a bidirectional corridor using a social force model
Authors: Kanté Dramane Sam Idris , Jebrane Aissam , Hakim Abdelilah , Boukamel Adnane
Published: July 2023

During infectious disease outbreaks, some infected individuals may spread the disease widely and amplify risks in the community. People whose daily activities bring them in close proximity to many others can unknowingly become superspreaders. The use of contact tracking based on social networks, GPS, or mobile tracking data can help to identify superspreaders and break the chain of transmission. We propose a model that aims at providing insight into risk factors of superspreading events. Here, we use a social force model to estimate the superspreading potential of individuals walking in a bidirectional corridor. First, we applied the model to identify parameters that favor exposure to an infectious person in scattered crowds. We find that low walking speed and high body mass both increase the expected number of close exposures. Panic events exacerbate the risks while social distancing reduces both the number and duration of close encounters. Further, in dense crowds, pedestrians interact more and cannot easily maintain the social distance between them. The number of exposures increases with the density of person in the corridor. The study of movements reveals that individuals walking toward the center of the corridor tend to rotate and zigzag more than those walking along the edges, and thus have higher risks of superspreading. The corridor model can be applied to designing risk reduction measures for specific high volume venues, including transit stations, stadiums, and schools.
Lifestyle factors that affect cognitive function–a longitudinal objective analysis
Authors: Kimura Noriyuki , Sasaki Yuuki , Masuda Teruaki , Ataka Takuya , Eguchi Atsuko , Kakuma Tatsuyuki , Matsubara Etsuro
Published: July 2023

Background

Identifying lifestyle factors associated with cognitive decline has critical clinical and public health implications for dementia prevention in later life. The longitudinal associations of sleep and physical activity with cognitive function remain unclear. This study examined whether objectively measured sleep and physical activity were longitudinally associated with cognitive function in older adults over a three-year period.

Methods

This prospective cohort study enrolled 855 community-dwelling adults aged 65 and older, who were followed from 2015 to 2019. All participants were required to wear a wearable sensor for 7 consecutive days every 3 months and had annual cognitive assessments. Wearable sensor data (August 2015–September 2019) and Mini-Mental State Examination (MMSE) scores (August 2015–April 2019) were collected over 3 years of follow-up. First, principal component analysis was conducted to reduce the dimensions of the sleep and physical activity variables to two principal components for inclusion in a mixed-effects model. The sleep index consisted of sleep efficiency, time awake after sleep onset, and waking frequency. The physical activity index was composed of walking comprised steps per day and time devoted to light or moderate-to-vigorous physical activity. A higher sleep index indicated poor sleep quality, whereas a lower physical activity index indicated less physical activity. Second, a linear mixed effect model was used to examine the longitudinal association of sleep and physical activity indices with cognitive decline over time.

Results

In total, 855 adults were recruited for this study at baseline. Of these, 729 adults (85.3%) completed a measurement of lifestyle factors and an annual cognitive testing, whereas 126 were excluded because of death or loss during follow-up. After adjusting for age, sex, education level, and time, the sleep index was inversely associated with MMSE scores (estimate, −0.06229; standard error, 0.02202; p = 0.0047) and the physical activity index was positively associated with MMSE scores (estimate, 0.06699; standard error, 0.03343; p = 0.0453).

Conclusion

Poor sleep quality and lower physical activity were significant risk factors for subsequent cognitive decline in older adults. The present study facilitates the development of novel evidence-based interventions for physical activity and sleep quality to delay cognitive decline.
A network analysis of the long-term quality of life and mental distress of COVID-19 survivors 1 year after hospital discharge
Authors: Peng Pu , Wang Yaqi , Li Zhuqing , Zhou Yanan , Wang Ji , Qu Miao , Liu Tieqiao
Published: July 2023

Objectives

COVID-19 survivors suffer from persistent mental distress and impaired quality of life (QOL) after recovery from the infection. However, the symptom-symptom interaction between these psychological variables remained unexplored. The present study aimed to determine the symptom network of mental distress (depression, anxiety, sleep disturbance, fatigue, and post-traumatic stress disorder) and their association with QOL among 535 COVID-19 survivors 1 year after hospital discharge.

Methods

9-item Patient Health Questionnaire, 7-item Generalized Anxiety Disorder Scale, Chalder fatigue scale, Impact of Event Scale-Revised, Pittsburgh Sleep Quality Index, and 36-Item Short-Form Health Survey were applied to measure depression, anxiety, fatigue, PTSD, sleep disturbances, and QOL, respectively. Two networks were estimated using Gaussian graphical model. Network 1 consisted of mental symptoms to determine the central and bridge symptoms. Network 2 additionally included QOL to determine which mental symptoms were mostly related to QOL.

Results

60% of the COVID-19 survivors experienced mental distress 1 year after hospital discharge. Uncontrollable and excessive worry, psychomotor symptoms, intrusion, and daytime dysfunction were the most central symptoms. Daytime dysfunction and fatigue (especially mental fatigue and loss of energy) served as the bridge symptoms across the mental distress network and exhibited the most substantial association with QOL.

Conclusion

Our study demonstrated several key symptoms that played a vital role in mental distress and QOL among COVID-19 survivors. Prompt screening and targeted interventions for these symptoms might hold great promise in preventing mental distress and improving QOL in COVID-19 survivors.
Robust design of a machine learning-based GNSS NLOS detector with multi-frequency features
Authors: García Crespillo Omar , Ruiz-Sicilia Juan Carlos , Kliman Ana , Marais Juliette
Published: July 2023

The robust detection of GNSS non-line-of-sight (NLOS) signals is of vital importance for land- and close-to-land-based safe navigation applications. The usage of GNSS measurements affected by NLOS can lead to large unbounded positioning errors and loss of safety. Due to the complex signal conditions in urban environments, the use of machine learning or artificial intelligence techniques and algorithms has recently been identified as potential tools to classify GNSS LOS/NLOS signals. The design of machine learning algorithms with GNSS features is an emerging field of research that must, however, be tackled carefully to avoid biased estimation results and to guarantee algorithms that can be generalized for different scenarios, receivers, antennas, and their specific installations and configurations. This work first provides new options to guarantee a proper generalization of trained algorithms by means of a pre-normalization of features with models extracted in open-sky (nominal) scenarios. The second main contribution focuses on designing a branched (or parallel) machine learning process to handle the intermittent presence of GNSS features in certain frequencies. This allows to exploit measurements in all available frequencies as compared to current approaches in the literature based on only the single frequency. The detection by means of logistic regression not only provides a binary LOS/NLOS decision but also an associated probability which can be used in the future as a means to weight-specific measurements. The detection with the proposed branched logistic regression with pre-normalized multi-frequency features has shown better results than the state-of-the-art algorithms, reaching 90% detection accuracy in the validation scenarios evaluated.
Precise macronutrient application can improve cane yield and nutrient uptake in widely spaced plant-ratoon cycles in the Indo-Gangetic plains of India
Authors: Kumar Navnit , Rana Lalita , Singh A. K. , Pramanick Biswajit , Gaber Ahmed , Alsuhaibani Amnah Mohammed , Skalicky Milan , Hossain Akbar
Published: July 2023

Introduction

Sugarcane is a long-duration and nutrient-exhaustive crop. To improve nutrient use efficiency, the 4R nutrient stewardship approach comprises applying nutrients at the right time and place with the right method and at the right proportion. Improper nutrient management in such a nutrient-exhaustive crop will result in various nutrient losses and environmental pollution.

Methods

Concerning this, a field study was performed on calcareous soils of the lower Indo-Gangetic plains of India during two subsequent years at the Sugarcane Research Institute, RPCAU, India, to explore the effect of precise application of macronutrients (N and K) in different methods of applications. The application methods (broadcasting and band application) were maintained in the main plot, and split N and K applications were put in the subplots.

Results and Discussion

A highly significant difference was observed in the numbers of millable cane, cane, and sugar yield under the split applications of fertilizer. The decline in millable cane numbers, cane, and sugar yield due to the broadcasting method was to the tune of 17.5 and 17.6%, 14.8 and 17.1%, and 14.7 and 15.8% in plant and ratoon crops, respectively as compared to band placement of the fertilizers. Yield increased by 16.0 and 15.1% under plant and ratoon crops, respectively, with seven split applications of N and K compared to the control (two split of N and no split application of K). Band placement of N and K fertilizers markedly improved the nitrogen uptake (284.1 and 287.3 kg ha−1, in plant and ratoon, respectively) and phosphorus uptake (34.9 and 28.3 kg ha−1 in plant and ratoon, respectively) when compared to broadcasting. Application of N and K in seven splits resulted in better availability of nutrients in the soil, thereby facilitating the higher NPK uptake by the plants and ratoon both comparing two split applications of N and no splitting of K. From this study, it was observed that the band placement coupled with seven splitting of N and K is the best fertilizer application protocol, ensuring higher growth, yield, quality, and nutrient uptake of sugarcane in the calcareous soils of the Indo-Gangetic plains.
A Conceptual Study on the Role of Blockchain in Sustainable Development of Public–Private Partnership
Authors: Tafuro Alessandra , Dammacco Giuseppe , Costa Antonio
Published: July 2023

Background: Studies have highlighted how public–private partnerships are characterized by a lack of transparency, low availability of data, low accountability, and, often, strong opportunism. All these factors do not allow potential interested parties to trust it. This undermines the possibility of good cooperation between the public and private sectors and has presented a great limit for the Public Private Partnerships (PPPs) diffusion. Several articles in the literature highlight, in general, the numerous advantages generated using the blockchain in different organizations. The adoption of blockchain in the operation of PPPs could be a solution to overcome the limitations encountered in public–private partnerships. The aim of this study is to propose a theoretical framework aimed at connecting two topics (PPPs and Blockchain)—analyzed separately by literature—to highlight how blockchain can correct the limitations inherent to the functioning of traditional PPPs. Methods: The authors applied a qualitative research method to examine the role of blockchain from a PPP perspective. The authors present a conceptual work in which they advance a theoretical framework by integrating and proposing new relationships between constructs and developing logical arguments for these associations. Through a problem-focused approach, besides presenting a solution to overcome the critical issues, the authors also put forward ideas to help fill a gap in the literature to date. Results: The study showed that blockchain can generate a major shift in the function of PPPs. On the one hand, it makes it possible to overcome many limitations that have hindered the development of partnerships, thus making it possible to spread them further, while on the other hand, it has a positive impact on the strategic role of PPPs in achieving sustainable development goals. Conclusions: Blockchain technology is considered very immature, probably because a single underlying standard does not exist and concepts are difficult to master. Based on state-of-the-art standards, blockchain has the potential to be considered a transformative or even disruptive innovation for PPPs.
Combustion Regimes in Turbulent Non-Premixed Flames for Space Propulsion
Authors: Martinez-Sanchis Daniel , Sternin Andrej , Haidn Oskar , Tajmar Martin
Published: July 2023

Direct numerical simulations of non-premixed fuel-rich methane–oxygen flames at 20 bar are conducted to investigate the turbulent mixing burning of gaseous propellants in rocket engines. The reacting flow is simulated by using an EBI-DNS solver within an OpenFOAM frame. The transport of species is resolved with finite-rate chemistry by using a complex skeletal mechanism that entails 21 species. Two different flames at low and high Reynolds numbers are considered to study the sensitivity of the flame dynamics to turbulence. Regime markers are used to measure the probability of the flow to burn in premixed and non-premixed conditions at different regions. The local heat release statistics are studied in order to understand the drivers in the development of the turbulent diffusion flame. Despite the eminent non-premixed configuration, a significant amount of combustion takes place in premixed conditions. Premixed combustion is viable in both lean and fuel-rich regions, relatively far from the stoichiometric line. It has been found that a growing turbulent kinetic energy is detrimental to combustion in fuel-rich premixed conditions. This is motivated by the disruption of the local premixed flame front, which promotes fuel transport into the diffusion flame. In addition, at downstream positions, higher turbulence enables the advection of methane into the lean core of the flame, enhancing the burning rates in these regions. Therefore, the primary effect of turbulence is to increase the fraction of propellants burnt in oxygen-rich and near-stoichiometric conditions. Consequently, the mixture fraction of the products shifts towards lean conditions, influencing combustion completion at downstream positions.
Generic Diagnostic Framework for Anomaly Detection—Application in Satellite and Spacecraft Systems
Authors: Bieber Marie , Verhagen Wim J. C. , Cosson Fabrice , Santos Bruno F.
Published: July 2023

Spacecraft systems collect health-related data continuously, which can give an indication of the systems’ health status. While they rarely occur, the repercussions of such system anomalies, faults, or failures can be severe, safety-critical and costly. Therefore, the data are used to anticipate any kind of anomalous behaviour. Typically this is performed by the use of simple thresholds or statistical techniques. Over the past few years, however, data-driven anomaly detection methods have been further developed and improved. They can help to automate the process of anomaly detection. However, it usually is time intensive and requires expertise to identify and implement suitable anomaly detection methods for specific systems, which is often not feasible for application at scale, for instance, when considering a satellite consisting of numerous systems and many more subsystems. To address this limitation, a generic diagnostic framework is proposed that identifies optimal anomaly detection techniques and data pre-processing and thresholding methods. The framework is applied to two publicly available spacecraft datasets and a real-life satellite dataset provided by the European Space Agency. The results show that the framework is robust and adaptive to different system data, providing a quick way to assess anomaly detection for the underlying system. It was found that including thresholding techniques significantly influences the quality of resulting anomaly detection models. With this, the framework can provide both a way forward in developing data-driven anomaly detection methods for spacecraft systems and guidance relative to the direction of anomaly detection method selection and implementation for specific use cases.
Exploring the Performance Boundaries of a Small Reconfigurable Multi-Mission UAV through Multidisciplinary Analysis
Authors: Santos Dioser , Rogers Jeremy , De Rezende Armando , Maldonado Victor
Published: July 2023

The performance of a small reconfigurable unmanned aerial vehicle (UAV) is evaluated, combining a multidisciplinary approach in the computational analysis of additive manufactured structures, fluid dynamics, and experiments. Reconfigurable UAVs promise cost savings and efficiency, without sacrificing performance, while demonstrating versatility to fulfill different mission profiles. The use of computational fluid dynamics (CFD) in UAV design produces higher accuracy aerodynamic data, which is particularly important for complex aircraft concepts such as blended wing bodies. To address challenges relating to anisotropic materials, the Tsai–Wu failure criterion is applied to the structural analysis, using CFD solutions as load inputs. Aerodynamic performance results show the low-speed variant attains an endurance of 1 h, 48 min, whereas its high-speed counterpart is 29 min at a 66.7% higher cruise speed. Each variant serves different aspects of small UAS deployment, with low speed envisioned for high-endurance surveying, and high speed for long-range or time-critical missions such as delivery. The experimental and simulation results suggest room for design iteration, in wing area and geometry adjustments. Structural simulations demonstrated the need for airframe improvements to the low-speed configuration. This paper highlights the potential of reconfigurable UAVs to be useful across multiple industries, advocating for further research and design improvements.
Selected Cultivar-Specific Parameters of Wheat Grain as Factors Influencing Intensity of Development of Grain Weevil Sitophilus granarius (L.)
Authors: Kordan Bożena , Nietupski Mariusz , Ludwiczak Emilia , Gabryś Beata , Cabaj Robert
Published: July 2023

Wheat, the main source of protein in the human diet, is a staple food in many countries. The yields and technological quality of wheat grain depend on both the yielding potential of wheat and the properties of wheat grain that allow its safe storage. To a large extent, losses during storage are caused by storage pests. Grains of 46 wheat cultivars were used in the study (samples weighing 20 g of each variety in 10 replications), on which the development of the grain weevil Sitophilus granarius (L.) (Coleoptera: Curculionidae) was observed (20 insects aged 3–4 days; sex ratio of 1:1). The laboratory study was carried out at constant temperature (27 OC) and humidity (75% relative humidity). The laboratory study demonstrated that the physicochemical parameters of grain (hardness, glassiness, flouriness, content of protein, sugars, starch, and crude fat), which are cultivar-dependent, can act as regulators of the development of the grain weevil. The main aim of the study was to develop recommendations regarding the breeding of wheat cultivars resistant to the foraging of S. granarius and which could therefore produce grain for longer storage, and to distinguish those that are more sensitive to the grain weevil and whose grain should therefore be supplied to the market more quickly. Knowledge of the resistance or susceptibility of individual cereal varieties to the feeding of storage pests may be useful in integrated grain storage management. Among the 46 wheat cultivars studied, five cultivars with the highest and five cultivars with the lowest susceptibility to foraging by S. granarius were identified. The highest inherent tolerance to the grain weevil was displayed by the following cultivars: KWS Livius, Bogatka, Speedway, Platin, and Julius; in contrast, the cultivars Askalon, Bamberka, Ostroga, Forum, and Muszelka proved to be the most sensitive. The chemical and physical analysis of the selected cultivars revealed a significant, positive correlation between the intensity of the development of the grain weevil, the content of starch and crude fat in the grain, and grain hardness and flouriness.
Transcriptome-Wide Identification of Cytochrome P450s and GSTs from Spodoptera exigua Reveals Candidate Genes Involved in Camptothecin Detoxification
Authors: Zhao Zhenzhen , Zhang Lan , Zhang Yanning , Mao Liangang , Zhu Lizhen , Liu Xingang , Jiang Hongyun
Published: July 2023

The application of camptothecin (CPT) and its derivatives to control insect pests has generated significant interest. This study investigated the enzymatic response of cytochrome P450 monooxygenase (CYP) and glutathione S-transferase (GST) genes in the fat body cells of Spodoptera exigua after 10 μM CPT treatment. Additionally, we examined the effects of CPT on the growth and development of S. exigua larvae and detected the relative expression levels of selected CYP and GST genes during the CPT treatment period. Twenty-one CYP and 17 GST genes were identified from the fat body cells of S. exigua by comparative transcriptomic analyses. The relative expression of ten CYP and seven GST genes changed significantly, which suggested that these CPYs and GSTs may be involved in CPT metabolism. During exposure to CPT for 10 days, the development of S. exigua larvae was delayed and was characterized by weight inhibition and a prolonged period of development. The relative expression levels of the selected four CYP genes, CYP9A27, CYP9A186, CYP337B5, CYP321A8, and one GST gene, GSTe7, were significantly changed by CPT treatment compared to the control group. These generated data provide a basis for identifying the CPT metabolism/detoxification genes of S. exigua at the molecular level.
Navigation Line Extraction Method for Broad-Leaved Plants in the Multi-Period Environments of the High-Ridge Cultivation Mode
Authors: Zhou Xiangming , Zhang Xiuli , Zhao Renzhong , Chen Yong , Liu Xiaochan
Published: July 2023

Navigation line extraction is critical for precision agriculture and automatic navigation. A novel method for extracting navigation lines based on machine vision is proposed herein using a straight line detected based on a high-ridge crop row. Aiming at the low-level automation of machines in field environments of a high-ridge cultivation mode for broad-leaved plants, a navigation line extraction method suitable for multiple periods and with high timeliness is designed. The method comprises four sequentially linked phases: image segmentation, feature point extraction, navigation line calculation, and dynamic segmentation horizontal strip number feedback. The a* component of the CIE-Lab colour space is extracted to preliminarily extract the crop row features. The OTSU algorithm is combined with morphological processing to completely separate the crop rows and backgrounds. The crop row feature points are extracted using an improved isometric segmented vertical projection method. While calculating the navigation lines, an adaptive clustering method is used to cluster the adjacent feature points. A dynamic segmentation point clustering method is used to determine the final clustering feature point sets, and the feature point sets are optimised using lateral distance and point line distance methods. In the optimisation process, a linear regression method based on the Huber loss function is used to fit the optimised feature point set to obtain the crop row centreline, and the navigation line is calculated according to the two crop lines. Finally, before entering the next frame processing process, a feedback mechanism to calculate a number of horizontal strips for the next frame is introduced to improve the ability of the algorithm to adapt to multiple periods. The experimental results show that the proposed method can meet the efficiency requirements for visual navigation. The average time for the image processing of four samples is 38.53 ms. Compared with the least squares method, the proposed method can adapt to a longer growth period of crops.
Parameters Optimization and Performance Evaluation Model of Air-Assisted Electrostatic Sprayer for Citrus Orchards
Authors: Xue Xiuyun , Zeng Kaixiang , Li Nengchao , Luo Qin , Ji Yihang , Li Zhen , Lyu Shilei , Song Shuran
Published: July 2023

Citrus orchards in Southeast Asia are commonly grown in hilly areas, where the terrain is unsuitable for the operation of crop protection machinery. Conventional spraying equipment used in hilly orchards have a poor deposition effect. In this paper, a new air-assisted electrostatic sprayer was designed for hilly citrus orchards. The orthogonal method was conducted to determine the optimal spray parameters of the sprayer. To evaluate the spray performance of the optimized air-assisted electrostatic sprayer, field tests were carried out on a citrus orchard with various cultivation patterns. Based on the data of the field tests, a comprehensive evaluation model was constructed to quantitatively analyze the performance of the sprayer. Results indicate that the optimal parameters are a spray pressure of 0.5 MPa, applied voltage of 9 kV and air flow velocity of 10 m/s. The optimized air-assisted electrostatic sprayer has the best performance in the citrus under dense fence cultivation pattern, followed by dense dwarf cultivation pattern. Comparing to the other sprayers tested, the air-assisted electrostatic sprayer greatly improves the spray coverage on the leaf surfaces (abaxial and adaxial) under various cultivation patterns.
Vigor Detection for Naturally Aged Soybean Seeds Based on Polarized Hyperspectral Imaging Combined with Ensemble Learning Algorithm
Authors: Hu Qingying , Lu Wei , Guo Yuxin , He Wei , Luo Hui , Deng Yiming
Published: July 2023

To satisfy the increasing demand for soybeans, identifying and sorting high-vigor seeds before sowing is an effective way to improve the yield. Polarized hyperspectral imaging (PHI) technology is here proposed as a rapid, non-destructive method for detecting the vigor of naturally aged soybean seeds. First, the spectrum of 396.1–1044.1 nm was collected to automatically extract the region of interest (ROI). Then, first derivative (FD), Savitzky–Golay (SG), multiplicative scatter correction (MSC), and standard normal variate (SNV) preprocessed hyperspectral and polarized hyperspectral data (0°, 45°, 90°, and 135°) for the soybean seeds was obtained. Finally, the seed vigor prediction model based on polarized hyperspectral components such as I, Q, and U was constructed, and partial least squares regression (PLSR), back-propagation neural network (BPNN), generalized regression neural network (GRNN), support vector regression (SVR), random forest (RF), and blending ensemble learning were applied for modeling analysis. The results showed that the prediction accuracy when using PHI was improved to 93.36%, higher than that for the hyperspectral technique, with a prediction accuracy up to 97.17%, 98.25%, and 97.55% when using the polarization component of I, Q, and U, respectively.
Design and Testing of a Directional Clamping and Reverse Breaking Device for Corn Straw
Authors: He Xun , Fan Xudong , Wei Wenhe , Qu Zhe , Shi Jingzhao , Zhang Hongmei , Chen Bo
Published: July 2023

Realizing high-quality and increased production of fresh corn and promoting diversified development of the corn industry structure not only can effectively promote the development of agricultural economy, but also can enrich people’s dietary culture. However, existing fresh corn machinery has a high rate of ear damage during the harvesting process, and the overall harvesting efficiency is not ideal. To reduce damage during the harvesting of fresh corn, a device for breaking ears of fresh corn was designed based on the directional clamping of corn straw reverse breaking method. Based on the physico-mechanical characteristics parameters of fresh corn ears, the main structural parameters of the directional clamping and conveying mechanism and the ear-breaking mechanism were determined. The overall inclination angle of the device was 15°, and the effective conveying length of the directional clamping mechanism was 550 mm; the ear-snapping mechanism was a snapping roll composed of a pair of six radial distribution function fingers, with an effective operating radius of 320 mm. By simulating and analyzing the reverse breaking movement of directional clamping corn straw, the key motion parameter ranges of the directional clamping conveying mechanism and breaking mechanism were obtained. The results of the bench test showed that under the optimal conditions of a directional clamping feeding speed of 1.67 m/s, a breaking wheel speed of 80 rpm, and a travel speed of 1.06 m/s, the lowest ear damage rate was 0.57%, and the lowest impurity rate was 1.87%. In addition, it was observed that flexible harvesting can improve harvest efficiency and quality. The study also found that actively applying force to the device can effectively avoid the problem of machine blockage and reduce the damage rate of ears (the following text uses ears instead of fresh corn ears).