bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth and whole-body proximate composition of Oreochromis niloticus Nile tilapia fed pea meal: A systematic review and meta-analysis
Authors: Magbanua Tzodoq Obrero , Ragaza Janice Alano
Published: March 2023

One of the most widely cultivated species in the aquaculture sector is the Nile tilapia (Oreochromis niloticus). However, the rising price of fishmeal has a huge impact on its market value. Proteins derived from plants have been used to address the issue. In this study, systematic review and meta-analysis were used to quantitatively analyze the whole-body composition and growth of Nile tilapia fed pea meal. Based on the preferred reporting items for systematic reviews and meta-analysis methods, the literature review and paper selection were completed. Meta-analysis was performed on the data from peer-reviewed studies that met the inclusion screening requirements, namely: tilapia development stage, standard error reporting, feeding period, lack of nutritional supplements, and crude protein levels. The control diet outperformed the plant-based diets according to the result, in which growth and feed utilization characteristics were significantly different (P < 0.05). All except the final weight were significantly better (P < 0.05) in tilapia fed control compared to tilapia fed pea treatment. Additionally, the pooled estimate of whole-body composition of fish fed a diet based on pea meal was not substantially different from that of fish fed a diet based on fishmeal (P > 0.05). Due to large and statistically significant I2 values, the feeding interval, crude protein concentration, fish development stage, and dietary pea meal inclusions were all examined using meta-regression analysis to identify the sources of heterogeneity. Not all co-variates explained the heterogeneity except for the feeding period and crude protein % in some of the parameters. The minimum quantities of dietary pea meal needed for best Nile tilapia performance in terms of growth, feed utilization, and whole-body composition were found to be 4.9, 488.6, and 210.3 g kg−1, respectively.
Modeling Hawaiian Agroecology: Depicting traditional adaptation to the world's most diverse environment
Authors: Lincoln Noa Kekuewa , Haensel Thomas P. , Lee Tiffany M.
Published: March 2023

Most neglected and underutilized crops were developed and utilized within indigenous agroecological cropping systems. While crop suitability must consider the constraints of the environment, the conditions of agroecological systems and the role of crops within those systems should be considered. Such consideration may guide the implementation of appropriate farming systems specific to different ecosystems and microhabitats. Using the Hawaiian archipelago as a model system of socioecological dynamics, we consider the distribution of agroecological systems and their associated crops to explore how agroecological suitability changes across climate, topography, and soils. We conduct spatial modeling of the potential nature and extent of seven agroecological archetypes based on historical records. The seven spatial models of pre-colonial agroecological systems produced extents distributed across much of the Hawaiian archipelago, with clear adaptive patterns within and across the islands. The distribution of cropping system further affects the appropriateness of crop species application. We argue that the consideration of agroecological niches and associated cropping systems is critical for realizing the potential of underutilized crops and improving the efficiency of contemporary agricultural systems.
Effects of dietary chromium supplementation on dry matter intake and milk production and composition in lactating dairy cows: A meta-analysis
Authors: Malik Muhammad I. , Raboisson Didier , Zhang Xin , Sun Xuezhao
Published: March 2023

Introduction

Chromium (Cr) is an essential mineral that has been demonstrated to enhance milk production in dairy cows. This study aims to evaluate the effects of dietary Cr supplementation on dry matter intake (DMI), milk production and composition using a meta-analysis based on existing literature.

Methods

A random effects meta-analysis was performed to investigate the effects of dietary Cr supplementation on DMI, milk production and composition. The heterogeneity was assessed using the I2 statistic and Q test, while Egger's test was used to evaluate publication bias.

Results

The meta-analysis discovered that Cr-supplemented cows had a significantly higher DMI compared to those not supplemented, with an increase of 0.72 kg/day [95% confidence interval (CI), 0.46–0.97]. The regression model indicated that DMI significantly increased by 0.9 g/kg of body weight (BW) and by 80.5 g for an increase of 1 mg of Cr supplement. The supplementation phase was associated with an increase in DMI, with an increase of 0.4582 kg/day for BFP (before parturition) and 0.853 kg/day for AFP (after parturition). The methionine and yeast forms of Cr increased DMI by 0.714 and 1.137 kg/day, respectively. The DMI was increased by 2.137 and 0.620 kg/day for multiparous (MP)+ primiparous (PP) cows and MP cows, respectively. Milk production was also increased by Cr supplementation, with an increase of 1.20 kg/day (95% CI, 0.65–1.76). The regression model indicated that milk production increased by 2.3 g/day for an increase of 1 kg of BW and by 122.4 g/day for an increase of 1 mg of Cr supplement. Milk production also increased with the duration of the experiment and days in milk. The amino acid and methionine forms of Cr complexes increased milk production by 1.645 and 1.448 kg/day, respectively. Milk production increased by 1.087 and 1.920 kg/day for MP and PP cows, respectively. Milk composition was not significantly affected by Cr supplementation. Egger's test for publication biases was not significant for all responses of interest.

Discussion

The meta-analysis showed that Cr supplementation improves DMI and milk production in dairy cows. The results suggest that the supplementation phase, form of Cr, and parity should be considered when supplementing dairy cows with Cr. The results have important implications for the dairy industry and can contribute to the development of more effective feeding strategies for dairy cows.
Transplantation of fecal filtrate to neonatal pigs reduces post-weaning diarrhea: A pilot study
Authors: Larsen Christina , Andersen Amanda B. , Sato Helena , Brunse Anders , Thymann Thomas
Published: March 2023

Post-weaning diarrhea (PWD) remains a major source of mortality and morbidity in swine production. Transplantation of bacteria-free filtrate of feces (fecal filtrate transplant, FFT) has shown gut protective effects in neonatal pigs, and early postnatal establishment of the gut microbiome is suggested to determine later stability and robustness of the gut. We, therefore, hypothesized that early postnatal transplantation of bacteria-free feces would have a protective effect against PWD. Using fecal filtrates derived from healthy lactating sows, we compared oral administration of fecal filtrate transplantation (FFT, n = 20) and saline (CON, n = 18) in newborn piglets. We assessed growth, diarrhea prevalence, blood parameters, organ measurements, morphology, and gut brush border enzymes and analyzed luminal bacterial composition using 16S rRNA gene amplicon sequencing. The two groups showed similar average daily gain (ADG) during the suckling period, whereas in the post-weaning period, a negative ADG was observed in both groups. While diarrhea was largely absent in both groups before weaning, there was a lower diarrhea prevalence on days 27 (p = 2.07*10−9), 28 (p = 0.04), and 35 (p = 0.04) in the FFT group relative to CON. At weaning on day 27, the FFT group had higher numbers of red blood cells, monocytes, and lymphocytes, while on day 35, i.e., 1 week after weaning, the two groups were similar regarding hematology. The biochemical profile was largely similar between FFT and CON on days 27 and 35, except for a higher level of alanine aminotransferase and a lower level of Mg in the FFT group. Likewise, organ weights relative to body weight were largely similar on day 35, albeit with a lower stomach weight and more colon content in FFT relative to CON. Gut mucosal percentage and mucosal enzyme activity were similar between the two groups on days 27 and 35. Gut bacterial composition was slightly different on day 35 but not on day 27. In conclusion, early postnatal administration of FFT, showed positive clinical effects in post-weaning pigs, albeit with subtle effects on the gut mucosa and microbiome. Prophylactic treatment with FFT may offer a means to reduce morbidity, yet larger studies are required to document effect size.
Impact of Insomnia on Burnout Among Chinese Nurses Under the Regular COVID-19 Epidemic Prevention and Control: Parallel Mediating Effects of Anxiety and Depression
Authors: Mao Xiaofei , Lin Xueru , Liu Peng , Zhang Jianguo , Deng Wenxi , Li Ziqiang , Hou Tianya , Dong Wei
Published: March 2023

Objective: To investigate the mediating effects of anxiety and depression in the relationship between insomnia and burnout among Chinese nurses under the regular COVID-19 epidemic prevention and control.

Methods: Convenience sampling was applied to recruit 784 nurses in Jiangsu Province, China. The respondents completed the survey via mobile devices. Demographic questionnaire, Insomnia Severity Index, Generalized Anxiety Disorder-7, Patient Health Questionnaire-9 and Maslach Burnout Inventory were used to assess demographic information, insomnia, anxiety, depression, and burnout, respectively. Hayes PROCESS macro was employed to examine the mediation model.

Results: Insomnia, anxiety, depression and burnout were positively and significantly associated with each other. Anxiety and depression played partial mediation effects between insomnia and burnout with the mediation effect of anxiety and depression accounting for 28.87% and 31.69% of the total effect, respectively.

Conclusion: Insomnia may lead to burnout through the parallel mediating effects of anxiety and depression in Chinese nurses. Interventions on sleep, anxiety and depression from the hospital management were essential to ameliorate nurses’ burnout status under the regular COVID-19 epidemic prevention and control.
COVID-19 Disruption and Meaningful Work: The Mediating Role of Family–Work Conflict
Authors: Vara-Horna Arístides Alfredo , Espinosa-Domínguez Amparo Guadalupe
Published: March 2023

Work overload and the alteration in family dynamics caused by the COVID-19 pandemic crisis may be increasing family–work conflict, leading to the consequent decrease in meaningful work. Using the structural equation modeling of covariance, this research determines the impact of the pandemic disruption on meaningful work as mediated through family–work conflict. The sample comes from 534 men and 257 women that are full-time employees of seven public manufacturing companies in Bolivia; they were surveyed by filling out a self-report questionnaire at the companies’ locations. Although no significant direct effects were found between COVID-19 disruption and meaningful work (standardized beta = 0.038, Z = 0.756, p = 0.450), there is an indirect effect when the relationship is measured through the family–work life conflict variable (standardized beta = −0.138, Z = −6.119, p < 0.001). Implications for business management are discussed.
Prediction of Capacity Regulations in Airspace Based on Timing and Air Traffic Situation
Authors: Pérez Moreno Francisco , Gómez Comendador Víctor Fernando , Delgado-Aguilera Jurado Raquel , Zamarreño Suárez María , Arnaldo Valdés Rosa María
Published: March 2023

The Air Traffic Control (ATC) system suffers from an ever-increasing demand for aircraft, leading to capacity issues. For this reason, airspace is regulated by limiting the entry of aircraft into the airspace. Knowledge of these regulations before they occur would allow the ATC system to be aware of conflicting areas of the airspace, and to manage both its human and technological resources to lessen the effect of the expected regulations. Therefore, this paper develops a methodology in which the final result is a machine learning model that allows predicting capacity regulations. Predictions shall be based mainly on historical data, but also on the traffic situation at the time of the prediction. The results of tests of the model in a sector of Spanish airspace are satisfactory. In addition to testing the model results, special emphasis is placed on the explainability of the model. This explainability will help to understand the basis of the predictions and validate them from an operational point of view. The main conclusion after testing the model is that this model works well. Therefore, it is possible to predict when an ATC sector will be regulated or not based mainly on historical data.
A Model-Based Prognostic Framework for Electromechanical Actuators Based on Metaheuristic Algorithms
Authors: Baldo Leonardo , Querques Ivana , Dalla Vedova Matteo Davide Lorenzo , Maggiore Paolo
Published: March 2023

The deployment of electro-mechanical actuators plays an important role towards the adoption of the more electric aircraft (MEA) philosophy. On the other hand, a seamless substitution of EMAs, in place of more traditional hydraulic solutions, is still set back, due to the shortage of real-life and reliability data regarding their failure modes. One way to work around this problem is providing a capillary EMA prognostics and health management (PHM) system capable of recognizing failures before they actually undermine the ability of the safety-critical system to perform its functions. The aim of this work is the development of a model-based prognostic framework for PMSM-based EMAs leveraging a metaheuristic algorithm: the evolutionary (differential evolution (DE)) and swarm intelligence (particle swarm (PSO), grey wolf (GWO)) methods are considered. Several failures (dry friction, backlash, short circuit, eccentricity, and proportional gain) are simulated by a reference model, and then detected and identified by the envisioned prognostic method, which employs a low fidelity monitoring model. The paper findings are analysed, showing good results and proving that this strategy could be executed and integrated in more complex routines, supporting EMAs adoption, with positive impacts on system safety and reliability in the aerospace and industrial field.
Opportunities and Challenges for Cover Cropping in Sustainable Agriculture Systems in Southern Australia
Authors: Nordblom Thomas , Gurusinghe Saliya , Erbacher Andrew , Weston Leslie A.
Published: March 2023

Southern Australian farming systems operate predominantly under Mediterranean climatic conditions, which limit the choice of cover crops suitable for enhancement of ground cover and soil moisture retention, erosion control, atmospheric soil nitrogen (N) fixation, and weed suppression between cash crop rotations. Given that the successful establishment of cover crops is climate-driven and also influenced by edaphic factors such as soil pH and salinity, there has been increased interest by southern Australian producers in identifying potential cover crop species well adapted to specific Australian farming systems, which provide vital ecosystem services and sustainable economic benefits through the improvement of soil properties. This review summarises recent findings on cover crop inclusion in diverse farming systems in southern Australia, including continuous and mixed broadacre cropping as well as viticulture and horticulture systems, to identify opportunities and limitations related to their use. Cover crop inclusion in viticulture and pasture systems with lower moisture stress was observed to benefit the subsequent cash crop through enhanced production potential. Long-term, multi-site field experimentation incorporating summer cover crops in winter crop rotations showed that cover crops enhanced ground cover and soil water infiltration in some locations across southern Australia while sometimes increasing winter crop yield, suggesting that soil type and regional climatic conditions greatly influenced the delivery of multiple cover crop benefits. Collectively, these studies have suggested a need for longer-term field evaluations using multiple cover crop species and investigations of termination options under varying environmental and soil conditions to better quantify the legacy effects of cover crops.
Assessment of NDVI Dynamics of Maize (Zea mays L.) and Its Relation to Grain Yield in a Polyfactorial Experiment Based on Remote Sensing
Authors: Tamás András , Kovács Elza , Horváth Éva , Juhász Csaba , Radócz László , Rátonyi Tamás , Ragán Péter
Published: March 2023

Remote sensing is an efficient tool to detect vegetation heterogeneity and dynamics of crop development in real-time. In this study, the performance of three maize hybrids (Fornad FAO-420, Merida FAO-380, and Corasano FAO-490-510) was monitored as a function of nitrogen dose (0, 80 and 160 kg N ha−1), soil tillage technologies (winter ploughing, strip-tillage, and ripping), and irrigation (rainfed and 3 × 25 mm) in a warm temperature dry region of East-Central Europe. Dynamics of the Normalized Difference Vegetation Index (NDVI) were followed in the vegetation period of 2021, a year of drought, by using sensors mounted on an unmanned aerial vehicle. N-fertilization resulted in significantly higher NDVI throughout the entire vegetation period (p < 0.001) in each experimental combination. A significant positive effect of irrigation was observed on the NDVI during the drought period (77–141 days after sowing). For both the tillage technologies and hybrids, NDVI was found to be significantly different between treatments, but showing different dynamics. Grain yield was in strong positive correlation with the NDVI between the late vegetative and the early generative stages (r = 0.80–0.84). The findings suggest that the NDVI dynamics is an adequate indicator for evaluating the impact of different treatments on plant development and yield prediction.
Identification of the Spectral Patterns of Cultivated Plants and Weeds: Hyperspectral Vegetation Indices
Authors: Danilov Roman , Kremneva Oksana , Pachkin Alexey
Published: March 2023

The accurate recognition of weeds on crops supports the spot application of herbicides, the high economic effect and reduction of pesticide pressure on agrocenoses. We consider the approach based on the quantitative spectral characteristics of plant objects to be the most appropriate for the development of methods for the spot application of herbicides. We made test plots with different species composition of cultivated and weed plants on the experimental fields of the scientific crop rotation of the Federal Research Center of Biological Plant Protection. These plants form the basis of the agrocenoses of Krasnodar Krai. Our primary subjects are sunflower crops (Helianthus annuus L.), corn (Zea mais L.) and soybean (Glycine max (L.)). Besides the test plots, pure and mixed backgrounds of weeds were identified, represented by the following species: ragweed (Ambrosia artemisiifolia L.), California-bur (Xanthium strumarium L.), red-root amaranth (Amaranthus retroflexus L.), white marrow (C. album L.) and field milk thistle (Sonchus arvensis L.). We used the Ocean Optics Maya 2000-Pro automated spectrometer to conduct high-precision ground-based spectrometric measurements of selected plants. We calculated the values of 15 generally accepted spectral index dependencies based on data processing from ground hyperspectral measurements of cultivated and weed plants. They aided in evaluating certain vegetation parameters. Factor analysis determined the relationship structure of variable values of hyperspectral vegetation indices into individual factor patterns. The analysis of variance assessed the information content of the indicators of index values within the limits of the selected factors. We concluded that most of the plant objects under consideration are characterized by the homogeneity of signs according to the values of the index indicators that make up the selected factors. However, in most of the cases, it is possible to identify different plant backgrounds, both by the values of individual vegetation indices and by generalized factorial coefficients. Our research results are important for the validation of remote aerospace observations using multispectral and hyperspectral instruments.
Anatomical and Physiological Characteristics of Awn Development in Elymus nutans, an Important Forage Grass in Qinghai-Tibet Plateau
Authors: Qiu Yongsen , Xie Wengang
Published: March 2023

Awns are the important structures of inflorescence in many crops that belong to the Poaceae family. In addition, they actively participate in photosynthesis, transpiration, seed dispersal, and self-planting. The Elymus nutans Griseb. is an important, self-pollinated, allohexaploid (2n = 6x = 42) and perennial native forage grass in Qinghai-Tibet Plateau that shows variation in awns length. However, the changes in the anatomical structure, physiological traits, and biochemical characteristics during awn development remain unclear in E. nutans. Therefore, this study investigated the changes in anatomical structures, enzymatic activities, and hormonal regulations of awns at four developmental stages, i.e., booting, heading, flowering, and maturity stages of three E. nutans accessions having different awn lengths. The results showed that the cross-sections of E. nutans awns had an acute triangular shape and structural similarities to wheat awns. In addition, the growth of long awns was recorded faster than short awns at the heading stage, but no significant differences in awns lengths were found at the heading, flowering, and maturity stages. The differences in the sizes of barbs and stomata of three accessions were statistically non-significant; however, the accession with long awns had more stomata than the accession with shorter awns at all developmental stages. In addition, the content of cytokinin (CTK), abscisic acid (ABA), and ethylene (ETH), and activities of superoxide dismutase (SOD) and peroxidase (POD) were significantly related to the development of awn. At the flowering stage, the content of CTK, and activities of SOD and POD of long awn accession were significantly higher than the short awn accession. Therefore, the obtained results provide a sound basis for future research on the molecular mechanisms of awn development and their potential role in E. nutans.
The Role of Symbiont-Targeted Strategies in the Management of Pentatomidae and Tephritidae Pests under an Integrated Vision
Authors: Gonella Elena , Alma Alberto
Published: March 2023

The interaction between insects and gut bacterial symbionts is, nowadays, regarded as an important element in the implementation of pest management, in consideration of the urgent need for sustainable alternatives to insecticide use. In this framework, a major tool is symbiotic control, with the main ready-to-use application represented by the interruption of obligate symbioses. Two insect families, namely Pentatomidae in the Hemiptera order and Tephritidae in Diptera, have been indicated as outstanding targets for symbiont-oriented control tactics. An important advantage of interrupting obligate symbioses is the target shift from insect to bacteria, which avoids insecticide use; however, the compatibility between this approach and other pest/disease management strategies is crucial to design low-impact pest control programs. Here we present the state of knowledge regarding the integration of symbiont manipulation in sustainable plant protection plans. Research assessing the potential for multitarget applications is reported, as well as studies on the impact of symbiont interruption on nontarget species. Besides symbiont-targeted pest control, another relevant outcome of symbiont manipulation is the restoration of microbial perturbation in mass-reared insects used in pest control programs, which is a required step to allow the success of other tactics, such as the Sterile Insect Technique. Despite the potential contribution that symbiont-targeted strategies may offer to integrated pest management, we point out that operational caveats may emerge in symbiont-oriented control in relation to the target extension on the label directions and to the number of required treatments. Future work is needed to increase the target range and the number of tested formulations exploiting the interruption of bacterial symbioses. This will also require assessment of the effect of different products on beneficial organisms, including biological control agents. Finally, the authorization of formulates for symbiotic control should be taken into consideration by the regulatory bodies, to really promote new readily available control options.
Endophytic Fusarium proliferatum Reprogrammed Phytohormone Production and Antioxidant System of Oryza sativa under Drought Stress
Authors: Seema Nighat , Hamayun Muhammad , Hussain Anwar , Shah Mohib , Irshad Muhammad , Qadir Muhammad , Iqbal Amjad , Alrefaei Abdulwahed Fahad , Ali Sajid
Published: March 2023

The aim of the current study was to isolate endophytes from the roots of Rhazya stricta and assess their potential to improve the growth of drought-stressed sunflower seedlings. The potential role of the isolated endophytic fungus was initially screened by using two rice varieties (mutant rice cultivar Waito-C: Gibberellins deficient; and Dongji byeo: Gibberellins-producing normal cultivar). A significant (p < 0.05) increase in various growth attributes of both rice varieties associated with one of the isolates i.e., N4 was noticed. Furthermore, the N4 isolate was tested for its role in improving the agronomic attributes of sunflowers under drought stress. The symbiotic association significantly (p < 0.05) improved the host growth and protection from PEG-induced drought stress. The drought mitigation in N4-associated sunflower seedlings can be linked with the regulation of phytohormones, stress-related metabolites, low-molecular-weight proteins and sugars, and scavenging of reactive oxygen species (ROS). Microscopic analysis revealed that the potent endophytic fungal strain consisted of thin and hyaline hyphae, forming dense olive-green mycelia (4–5 cm in dm) with black flask-shaped fruiting bodies. Based on the ITS sequence homology and phylogeny, the strain was identified as Fusarium proliferatum (MG251448). The results of this study concluded that this phytohormone-secreting endophyte can improve crop productivity in dry areas where drought stress is the main challenge faced by crops.
Attitudes and Beliefs of a Sample of Australian Dog and Cat Owners towards Pet Confinement
Authors: Rand Jacquie , Ahmadabadi Zohre , Norris Jade , Franklin Michael
Published: March 2023

Most cats and dogs entering Australian animal shelters and municipal facilities are classed as strays, typically from low socio-economic areas. Contemporary practices increasingly focus on proactively reducing the number of stray animals, which requires further understanding of factors associated with straying animals, including pet confinement. Australian cat and dog owners (n = 2103) were surveyed to investigate attitudes towards four types of pet confinement and how these were influenced by social norms, demographics and concerns about pet quality of life and potential wildlife predation. Dog owners showed the strongest support for confining dogs to the owners’ property whenever unsupervised (98% agreement) and less support for confining dogs inside the house at night (54% agreement), and only 23% believed dogs had a negative impact on wildlife. Cat owners showed the strongest support for confining cats inside the house at night (89% agreement). Cat owners’ non-supportive attitudes towards cat confinement were partly because of higher concern for cat quality of life and lower concern about their cats’ predation behaviours, compared to non-cat owners. The findings provide valuable information to inform more effective strategies to reduce stray animals which would reduce shelter admissions, euthanasia, costs, nuisance issues, potential wildlife predation and negative mental health impacts of euthanasia on staff. Strategies to reduce strays include assisting low-income pet owners to install effective fencing and programs to increase identification. Informing cat owners about bedtime feeding is recommended to assist with night containment, and providing high-intensity free sterilization of owned and semi-owned cats targeted to areas of high cat impoundments is also recommended.
Lytic Bacteriophage Is a Promising Adjunct to Common Antibiotics across Cystic Fibrosis Clinical Strains and Culture Models of Pseudomonas aeruginosa Infection
Authors: Martin Isaac , Morales Sandra , Alton Eric W. F. W. , Davies Jane C.
Published: March 2023

Bacteriophages (phages) are antimicrobials with resurgent interest that are being investigated for the treatment of antibiotic refractory infection, including for Pseudomonas aeruginosa (Pa) lung infection in cystic fibrosis (CF). In vitro work supports the use of this therapy in planktonic and biofilm culture models; however, consistent data are lacking for efficacy across different clinical Pa strains, culture models, and in combination with antibiotics in clinical use. We first examined the efficacy of a 4-phage cocktail as an adjunct to our CF centre’s first-line systemic combination antibiotic therapy (ceftazidime + tobramycin) for 16 different clinical Pa strains and then determined subinhibitory interactions for a subset of these strains with each antibiotic in planktonic and biofilm culture. When a 4-phage cocktail (4 × 108 PFU/mL) was added to a ceftazidime-tobramycin combination (ceftazidime 16 mg/mL + tobramycin 8 mg/mL), we observed a 1.7-fold and 1.3-fold reduction in biofilm biomass and cell viability, respectively. The four most antibiotic resistant strains in biofilm were very susceptible to phage treatment. When subinhibitory concentrations of antibiotics and phages were investigated, we observed additivity/synergy as well as antagonism/inhibition of effect that varied across the clinical strains and culture model. In general, more additivity was seen with the phage-ceftazidime combination than with phage-tobramycin, particularly in biofilm culture, where no instances of additivity were seen when phages were combined with tobramycin. The fact that different bacterial strains were susceptible to phage treatment when compared to standard antibiotics is promising and these results may be relevant to ongoing clinical trials exploring the use of phages, in particular in the selection of subjects for clinical trials.
Association of Serum 25-Hydroxyvitamin D and Vitamin D Intake with the Prevalence of Metabolic Syndrome in Korean Adults: 2013–2014 Korea National Health and Nutrition Examination Survey
Authors: Yoon Su-In , Min Jae-Yeon , Ly Sun Yung , Song SuJin , Cho Jin Ah
Published: March 2023

Vitamin D deficiency is prevalent in Korea and an insufficient vitamin D status increases the risk of various chronic diseases including metabolic syndrome (MetS). We examined the relationship between serum 25-hydroxyvitamin D (25(OH)D) levels, dietary vitamin D intake, and MetS. The 2013–2014 Korea National Health and Nutrition Examination Survey’s (KNHANES) included participants (n = 4.541; 1145 men; 1368 women) who were aged ≥19. In men, higher serum 25(OH)D levels were correlated with significantly increased protein intake (p = 0.032) and saturated fatty acid intake (p = 0.006), but significantly decreased fat intake (p = 0.027), monounsaturated fatty acid intake (p = 0.005), and polyunsaturated fatty acid intake (p = 0.003), and significantly decreased serum triglycerides levels (p = 0.002), whereas women had no association with any dietary intake or biochemical markers. Furthermore, our study found a significant negative correlation between abdominal obesity (OR, 0.970; CI, 0.946, 0.994) and hypertriglyceridemia (OR, 0.974; CI, 0.950, 0.998) and serum 25(OH)D levels in men, as well as a significant decrease in hypertriglyceridemia (OR, 0.980; CI, 0.961, 0.999) with vitamin D intake. However, women had a significantly negative correlation between serum LDL cholesterol (β, −1.751; p = 0.018) and vitamin D intake. By increasing the vitamin D intake and serum 25(OH)D levels, Korean adults could reduce their risk of MetS-related factors.
Lubrication Analysis of Small-End Bearings of Reciprocating Engines Based on Orthogonal Experiment
Authors: Sun Sicong , Yang Xin , Zhou Jianming , Yang Jianguo , Cai Yong , Xie Liangtao , Hu Jia
Published: March 2023

Small end bearings are a critical component of reciprocating engines, and the performance of their lubrication performance directly affects engines’ reliability and mechanical efficiency. There are many factors that influence their lubrication. A new type of small-end bearing test rig was developed to reveal key influencing factors and their influence on lubrication characteristics, and a multi-body dynamic model coupled with elastohydrodynamic (EHD) characteristics was built. The model was verified through experiments. In accordance with the orthogonal experimental requirements, the impact of various factors on small-end bearing lubrication characteristics was analyzed, and the results showed that: (1) minimal oil film thickness (MOFT), friction power, and maximum oil film pressure (MOFP) are the major evaluation indicators of small-end bearing lubrication, and the most significant influencing factors are the pin bushings’ clearance, engine speed, and bushing surface roughness; (2) increasing the clearance of the pin bushings can increase the hydrodynamic lubrication percentage and the average thickness of the oil film, but it also reduces the local minimum thickness of the oil film; (3) an increase in roughness can improve the MOFT and enhance its carrying capacity, but may also increase friction power; and (4) high speeds can increase the thickness of the oil film between the piston pin and bushing and improve lubrication status, but it also increases friction power on the asperity contact region, reducing mechanical efficiency. The research results can be used for the design of connecting rod small-end bearings to improve their mechanical efficiency and reliability.
Secure PBFT Consensus-Based Lightweight Blockchain for Healthcare Application
Authors: Hegde Pawan , Maddikunta Praveen Kumar Reddy
Published: March 2023

Recent advancement in IoT technology has boosted the healthcare domain with enormous usage of IoT devices to provide elevated services to patients with chronic disorders on a real-time basis by the incorporation of IoT sensors on patients’ bodies. However, providing services ensuring security and maintaining the privacy of patients is a challenging task. Blockchain technology promises security in a distributed environment but popular consensus algorithms such as Proof of Work (PoW) and Proof of Stake (PoS) require huge computational resources and energy by making the IoT environment inefficient. This paper introduces a secure Practical Byzantine Fault Tolerance (PBFT) consensus-based lightweight blockchain algorithm for healthcare applications. To strengthen the PBFT consensus, highly trusted nodes were allowed to participate in the consensus algorithm using the Eigen Trust model and Verifiable Random Function (VRF) to select a random primary node from a group of trusted consensus nodes. The proposed algorithm is tested in a simulated environment and evaluated against the traditional PBFT consensus algorithm considering throughput, latency, and fault tolerance.
Joint Resource Allocation and Learning Optimization for UAV-Assisted Federated Learning
Authors: Liu Chaoyi , Zhu Qi
Published: March 2023

Aiming at the unmanned aerial vehicle (UAV)-assisted federated learning wireless-network scenario, and considering the influence of the UAV altitude on the coverage area, we propose a joint optimization algorithm of UAV placement, computation and communication resources. Considering the energy efficiency and federated learning performance, we defined the cost function of the system. Under the constraint of the total delay of federated learning completion, we formulated an optimization problem of minimizing the cost function to achieve the balance between the total energy consumption of users and the federated learning performance. Since the formulated optimization problem is a non-convex problem, in order to solve this problem, we decomposed it into three optimization subproblems: UAV horizontal placement, local accuracy and computation and communication resources. We used successive convex approximation (SCA), the Dinkelbach Method, the Bisection method and KKT condition, respectively, to solve the three subproblems, and finally obtain the optimal solutions through iteration of the three subproblems. Simulation results show that compared with the federated learning scenario under fixed UAV altitude, our proposed algorithm not only guarantees the learning performance, but also reduces more users’ total energy consumption.
Temperature- and Frequency-Dependent Nonlinearities of an Integrated Hydro-Pneumatic Suspension with Mixed Gas-Oil Emulsion Flow
Authors: Yin Yuming , Wang Zhenting , Fu Zhijun , Lu Jianshan , Rakheja Subhash
Published: March 2023

Hydro-pneumatic suspension (HPS) systems are increasingly being implemented in commercial vehicles and various industrial equipment, which is mainly attributed to the integration of adaptable nonlinear pneumatic stiffness and hydraulic damping properties. The integrated HPS design with a shared gas-oil chamber, however, leads to gas-oil emulsion flow within the suspension chambers, which intricately affects the internal and external properties of the HPS, especially under variations in temperature and excitation frequency. This study experimentally and analytically investigated the temperature- and frequency-dependent properties of the hydro-pneumatic suspension with the gas-oil emulsion. Laboratory experiments were performed under three different near-constant temperatures (30, 40, and 50 °C) in the 0.5–8 Hz frequency range. An analytical model of the HPS was formulated considering the effects of temperature on internal fluid properties, gas-oil emulsion flow between the coupled chambers, the dynamic seal friction, and polytropic change in the gas state. The internal parameters, including the gas volume fraction, the discharge coefficient of the emulsion, and the dynamic friction components, as well as the external stiffness and damping characteristics, were determined. The relationships between these properties and the system temperature, velocity, and excitation frequency were further investigated. The simulated responses obtained under different excitations showed reasonably good agreement with the experimental results of the HPS. The results suggested that increased temperature yielded greater equivalent stiffness and comparable damping properties of the system. The gas volume fraction, discharge coefficient, and magnitude of seal friction generally tended to increase with increasing temperature. Increased excitation frequency led to greater hysteresis in hydraulic damping force and seal friction, and reduced seal friction magnitude and Stribeck effect.
Numerical Study on Aerodynamic Characteristics of High-Speed Planing Trimaran
Authors: Cang Jiuyang , Zou Jin , Sun Hanbing , Wan Lei , Zan Liru
Published: March 2023

When the planing hull is sailing at high speed, the proportion of air resistance to the total resistance increases significantly. Therefore, by studying the aerodynamic characteristics of the planing hull shape, we can analyze the influence of the hull shape on the aerodynamic performance of the planing hull, and find a method to reduce the proportion of air resistance. The research took the planing trimaran as the research object, completed the wind tunnel test, and established the numerical simulation method by solving the RANS equation and combining the k-ε turbulence model. Combined with the wind tunnel test data, the calculation accuracy of the computational fluid dynamics (CFD) method was judged. Then, four superstructure shapes and two tail shapes were simulated by the CFD method, and the characteristics of the air resistance and airflow field of several drag reduction schemes with a volume Froude number between 7.00–17.51 were analyzed. The research focuses on the aerodynamic force of the planing hull. The results show that the circular arc stern has a more obvious drag reduction effect than the square stern, and the streamlined mid-arched superstructure has certain advantages in the drag reduction effect.
Metabolomics Approach to Reveal the Effects of Ocean Acidification on the Toxicity of Harmful Microalgae: A Review of the Literature
Authors: Tsui Tsz-Ki , Kong Hang-Kin
Published: March 2023

Climate change has been associated with intensified harmful algal blooms (HABs). Some harmful microalgae produce toxins that accumulate in food webs, adversely affecting the environment, public health and economy. Ocean acidification (OA) is a major consequence of high anthropogenic CO2 emissions. The carbon chemistry and pH of aquatic ecosystems have been significantly altered as a result. The impacts of climate change on the metabolisms of microalgae, especially toxin biosynthesis, remain largely unknown. This hinders the optimization of HAB mitigation for changed climate conditions. To bridge this knowledge gap, previous studies on the effects of ocean acidification on toxin biosynthesis in microalgae were reviewed. There was no solid conclusion for the toxicity change of saxitoxin-producing dinoflagellates from the genus Alexandrium after high CO2 treatment. Increased domoic acid content was observed in the diatom Pseudo-nitzschia. The brevetoxin content of Karenia brevis remained largely unchanged. The underlying regulatory mechanisms that account for the different toxicity levels observed have not been elucidated. Metabolic flux analysis is useful for investigating the carbon allocations of toxic microalgae under OA and revealing related metabolic pathways for toxin biosynthesis. Gaining knowledge of the responses of microalgae in high CO2 conditions will allow the better risk assessment of HABs in the future.
Association between the Rail Breakage Frequency in Beijing–Tianjin–Hebei High-Speed Railway and the Eurasian Atmospheric Circulation Anomaly
Authors: Huo Liwei , Xiao Linman , Wang Ji , Jin Dachao , Shi Yinglong , Zhang Qian
Published: March 2023

The spatiotemporal variations in the frequency of rail breakage (FRB) in the high-speed railway of the Beijing–Tianjin–Hebei (BTH) region and its relationship with atmospheric circulation anomalies and surface temperature are analyzed in this study, based on the monthly FRB data of BTH region and the ERA5 reanalysis data from 2010 to 2020. The frequency of rail breaking in the BTH region varies significantly depending on the season, with winter having the highest incidence. In fact, more than 60% of the total FRB in the BTH region occur during the winter season. Both the annual total and winter FRB in BTH region are very unevenly distributed in time and space, and both are relatively similar in spatial distribution patterns. The FRB in Beijing railway section is the most frequent, followed by Tianjin, and the lowest frequency is observed in Chengde. It is found that the increasing winter FRB in BTH region and the intensified Siberian high are related. When the Siberian high is strong, the East Asian winter monsoon and the East Asian Trough in the middle troposphere could be enhanced through atmospheric teleconnection, which is conducive to the cold air advection from northern high latitudes to the BTH region, resulting in an abnormally cold winter in BTH region, thus providing low temperatures for broken rails on high-speed railways, and vice versa. The research results might provide a scientific basis for monitoring and predicting the broken rails in BTH high-speed railway during winter, thereby providing a guarantee for the safe operation of the high-speed railway.
Mathematical Models of the Processes of Operation, Renewal and Degradation of a Fleet of Complex Technical Systems with Metrological Support
Authors: Khayrullin Rustam , Ershov Denis , Malahov Alexander , Levina Tatyana
Published: March 2023

(1) Background: The aim of the study is to develop a set of models for managing a fleet of complex technical systems with metrological support, allowing the simulation and management at all the stages of the life cycle of the complex technical systems, as well as to simulate the functioning of large fleets of complex technical systems, including up to several hundred thousand samples; (2) Methods: The authors use methods of mathematical modeling, methods of the theory of Markov and semi-Markov processes, methods of optimization, methods of reliability theory, and methods of probability theory and mathematical statistics; (3) Results: an interconnected set of mathematical models for managing a fleet of complex technical systems with metrological support was developed and the applied software was developed; (4) Conclusions: The set of models presented in the article allows for the adequate simulation of all the stages of the life cycle of large complex technical systems fleets, including up to several hundreds of thousands of samples, to optimize the functioning processes of a fleet of complex technical systems, to form strategies for fleet development, and to assess the risks associated with false and undetected failures, as well as the risks associated with the degradation of complex technical systems.
Origin of Neuroblasts in the Avian Otic Placode and Their Distributions in the Acoustic and Vestibular Ganglia
Authors: Hidalgo-Sánchez Matías , Callejas-Marín Antuca , Puelles Luis , Sánchez-Guardado Luis
Published: March 2023

The inner ear is a complex three-dimensional sensorial structure with auditory and vestibular functions. This intricate sensory organ originates from the otic placode, which generates the sensory elements of the membranous labyrinth, as well as all the ganglionic neuronal precursors. How auditory and vestibular neurons establish their fate identities remains to be determined. Their topological origin in the incipient otic placode could provide positional information before they migrate, to later segregate in specific portions of the acoustic and vestibular ganglia. To address this question, transplants of small portions of the avian otic placode were performed according to our previous fate map study, using the quail/chick chimeric graft model. All grafts taking small areas of the neurogenic placodal domain contributed neuroblasts to both acoustic and vestibular ganglia. A differential distribution of otic neurons in the anterior and posterior lobes of the vestibular ganglion, as well as in the proximal, intermediate, and distal portions of the acoustic ganglion, was found. Our results clearly show that, in birds, there does not seem to be a strict segregation of acoustic and vestibular neurons in the incipient otic placode.