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Abstract In robotic-assisted surgery (RAS), traditional surgical instruments without sensing capability cannot perceive accurate operational forces during the task, and such drawbacks can be largely intensified when sophisticated tasks involving flexible and slender arms with small end-effectors, such as in gastrointestinal endoscopic surgery (GES). In this study, we propose a microelectromechanical system (MEMS) piezoresistive 3-axial tactile sensor for GES forceps, which can intuitively provide surgeons with online force feedback during robotic surgery. The MEMS fabrication process facilitates sensor chips with miniaturized dimensions. The fully encapsulated tactile sensors can be effortlessly integrated into miniature GES forceps, which feature a slender diameter of just 3.5 mm and undergo meticulous calibration procedures via the least squares method. Through experiments, the sensor’s ability to accurately measure directional forces up to 1.2 N in the Z axis was validated, demonstrating an average relative error of only 1.18% compared with the full-scale output. The results indicate that this tactile sensor can provide effective 3-axial force sensing during surgical operations, such as grasping and pulling, and in ex vivo testing with a porcine stomach. The compact size, high precision, and integrability of the sensor establish solid foundations for clinical application in the operating theater.

Abstract The precision of deformation monitoring with Global Navigation Satellite System (GNSS) relative positioning is significantly influenced by the distance between the monitoring and base stations. In long strip regions, the considerable differences in station spacing lead to inconsistent monitoring precision among multiple stations. This presents a challenge to accurately model and predict the deformation pattern. To tackle this issue, this paper introduces a novel dual-base station constraint method. This method integrates the baseline length constraint between two base stations into the conventional relative positioning model. The formulae of the proposed method are first derived in detail. Then the data collected at eight monitoring stations in two strip regions of 6 km and 8 km over a 28-day period are used to validate the effectiveness of the proposed method. The quantitative analysis of monitoring precision consistency indicators and hypothesis testing on the correlation between monitoring precision and station spacing are conducted. The results show that: (1) median values of the East, North, and Up consistency indicators are reduced from 2.14, 1.41, and 1.83 to 0.91, 0.67, and 0.55 and from 1.85, 1.85, and 2.32 to 0.69, 1.00, and 0.87, respectively, indicating monitoring precision consistency improvement for two case studies; (2) the absolute values of the correlation coefficients between monitoring precision and station spacing decrease from 0.99, 0.94, and 0.98 to 0.09, 0.36, and 0.32. Using the t-test with a significant level of 0.01, it is demonstrated that there is no significant correlation between monitoring precision and station spacing when employing the proposed method.

Based on five periods of Landsat remote sensing data from 1980 to 2020, this study constructs a landscape ecological risk-ecosystem service value evaluation model and integrates it with a geodetector model to analyse the environmental benefits of the development of the “production–living–ecological space” pattern and its driving factors in the Xuzhou planning area. The results of the study are as follows: (1) Over the past 40 years, the expansion of living spaces has significantly encroached upon adjacent agricultural production areas and ecological spaces, such as forests and grasslands. Specifically, the areas of agricultural land, forests, and grassland have been diminished by 277.39 km2, 23.8 km2 and 12.93 km2, respectively; in contrast, urban and rural living spaces have increased by 238.62 km2 and 58.92 km2, alongside a rise in industrial production areas, water bodies, and other ecological spaces. (2) Throughout the 40-year period, both the landscape ecological risk (ERI) and ecosystem service value (ESV) in the study area have shown a decreasing trend. The proportion of high- and medium-high-risk areas of the ERI have decreased by 5.19% and 7.50%, respectively, while low, lower, and medium ecological risk areas have increased by 6.40%, 3.22% and 3.07%, respectively. In addition, low-ESV areas have increased by 14.22%, while the proportion of high- and medium-high-ESV areas have decreased by 1.16%. (3) There is a significant positive spatial correlation between the ERI and ESV. Regions with dense ecological spaces comprising forests, water bodies, and grasslands, particularly in the northeastern part of the Jiawang District and the southeastern part of the Tongshan District, demonstrate superior regional ecosystem service quality. The ERI and ESV are dominated by “high–high” and “low–high” aggregation. Conversely, in the southwestern part of the study area, the expansion of living space has led to the transformation of some agricultural land, forest land, and grassland into less risky construction land, resulting in a decline in the quality of regional ecosystem services. The local spatial correlation between the ERI and ESV changed from “high–high”, “low–low”, “low–high” agglomeration to “low–low” agglomeration. (4) Key factors influencing the spatial differentiation of the “production–living–ecological space” include the GDP, population density, soil type, and the distance to towns and roads. Among these, the interaction between population density and soil type has the most significant effect on the changes in the pattern of the “production–living–ecological space”.

In this study, enhanced pyridine bio-photodegradation with assistance of electricity was achieved. Meanwhile, photoelectron-hole played a vital role in accelerating pyridine biomineralization. The significant separation of photoelectron-hole was achieved with an external electric field, which provided sufficient electron donors and acceptors for pyridine biodegradation. The enhanced electron transport system activity also revealed the full utilization of photoelectron-hole by microbes at semiconductor-microbe interface with assistance of electricity. Microbial community analysis confirmed the enrichment of functional species related to pyridine biodegradation and electron transfer. Microbial function analysis and microbial co-occurrence networks analysis indicated that upregulated functional genes and positive interactions of different species were the important reasons for enhanced pyridine bio-photodegradation with external electric field. A possible mechanism of enhanced pyridine biodegradation was proposed, i.e., more photoelectrons and holes of semiconductors were utilized by microbes to accelerate reduction and oxidation of pyridine with the assistance of electrical stimulation. The excellent performance of the photoelectrical biodegradation system showed a potential alternative for recalcitrant organic wastewater treatment.

Abstract Minimally invasive surgery has attracted great attention due to small trauma, light pain, and quick recovery. Currently, most minimally invasive surgical robots lack the ability to force sense, resulting in high risks. Herein, a novel minimally invasive surgical force sensing and feedback system for minimally invasive surgical robot is proposed based on a flexible triaxial force capacitive sensor array. The capacitive force sensors utilize a microstructure electrode and orthogonal triangular pyramid microstructure to tackle the trade‐off between high sensitivity and wide‐detection range, showing 0–3 N detection range for normal force and high sensitivity of 69.19% N−1. Furthermore, the triaxial capacitive force sensors are integrated into the end‐effector of the minimally invasive surgical robot to form the minimally invasive surgical force sensing system. The system can show real‐time position of gripping or touching action, and the magnitude of triaxial force on the display surface. Importantly, the sensing force can further control the movement of the clamp, thus forming a novel force sensing and feedback system. The force sensing and feedback system of this minimally invasive surgical robot lays the foundation for its application in minimally invasive surgery andis expected to improve the safety and success of robotic‐assisted minimally invasive surgery.

For the sake of understanding the mechanism of deep subcriticality and high heterogeneity of neutron fluence rate in time–space on the neutron kinetics of the Accelerator-driven Subcritical Reactor Subcritical Reactor (ADSR) under varied beam transients and neutron spectra. A Monte Carlo homogenization approach for the neutron time–space kinetics of the ADSR is proposed in this study, and the influence mechanism on the kinetic parameters of the ADSR under varied neutron spectra, subcriticality, and beam transients is examined. The results show that the Monte Carlo homogenization for the α eigenvalue mode is more adaptable to the subcriticality characteristics under varied subcriticality; under beam transients, the relative differences in the kinetic parameters of the different modes of the ADSR with fast/thermal spectra increase with the depth of subcriticality, and the differences in neutron generation time for varied modes are larger than those of effective fraction of delayed neutron. Thus, it is recommended to use a more adaptable Monte Carlo homogenization method for the time–space kinetics of ADSR, and the effects of the high heterogeneity of neutron fluence rate and deep subcriticality in time–space on the neutron generation time should be considered.

Abstract. Background:. The potential benefit of arthroscopic surgery for osteoarthritic knee associated with medial meniscus tear is controversial. This study was conducted to determine the effect of pre-operative medial meniscus extrusion (MME) on arthroscopic surgery outcomes in the osteoarthritic knee associated with medial meniscus tear during a minimum 4-year follow-up. Methods:. This was a retrospective review of a total of 131 patients diagnosed with osteoarthritic knee associated with medial symptomatic degenerative meniscus tear who underwent arthroscopic surgery from January 2012 to December 2014 and were observed for more than 4 years. Patients were classified into two groups: MME ≥3 mm (major MME group, n = 54) and MME

The removal of contaminants of emerging concern (CECs) has become a hot research topic in the field of environmental engineering in recent years. In this work, a simple pyrolysis method was designed to prepare a high-performance biochar-loaded zero-valent copper (CuC) material for the catalytic degradation of antibiotics ENR by PMS. The results showed that 10 mg/L of ENR was completely removed within 30 min at an initial pH of 3, CuC 0.3 g/L, and PMS 2 mmol/L. Further studies confirmed that the reactive oxygen species (ROS) involved in ENR degradation are ·OH, SO4−·, 1O2, and O2−. Among them, 1O2 played a major role in degradation, whereas O2−· played a key role in the indirect generation of 1O2. On the one hand, CuC adsorbed and activated PMS to generate ·OH, SO4−· and O2−·. O2−· was unstable and reacted rapidly with H2O and ·OH to generate large amounts of 1O2. On the other hand, both the self-decomposition of PMS and direct activation of PMS by C=O on biochar also generated 1O2. Five byproducts were generated during degradation and eventually mineralized to CO2, H2O, NO3−, and F−. This study provides a facile strategy and new insights into the biochar-loaded zero-valent transition-metal-catalyzed PMS degradation of CECs.

Summary: This article proposed a high-performance triboelectric-electromagnetic hybrid wind energy harvester (WEH). By adopting the revolution and rotation movements of tapered rollers, which serve as both the rotor of the electromagnetic generator (EMG) part and freestanding layers of the triboelectric nanogenerator (TENG) part, the WEH can work as a sustainable power source and a self-powered wind speed sensor. When the wind speed is 12 m/s, super-high open-circuit voltage peaks of 47.4 and 683 V can be achieved by the EMG and TENG, respectively, corresponding to the high-power outputs of 62 and 1.8 mW. It was demonstrated that the WEH can easily light up over 600 red light-emitting diodes and even a 5-W globe light. A self-powered wireless temperature and humidity sensing network was also systematically demonstrated. In summary, the proposed WEH exhibits bright future toward IoT applications, such as in border detection, smart buildings, and so on.

In this study, the dynamic characteristics of accelerator-driven subcritical reactor (ADSR) under beam transients with high heterogeneity of neutron flux in time-space are investigated. Multi-mode core few-group constants are generated by three kinds of neutron fluxes: steady state of ADSR, λ-eigenvalue fundamental wave, and α-eigenvalue fundamental wave. The proposed few-group constants overcome the limitation of single few-group constant generated by two-step method that cannot consider the variation in neutron flux density and neutron energy spectrum with time and space. Compared to the existing few-group constants generated by two-step method under different operating conditions, the self-adapting multi-mode core few-group constants exhibit higher accuracy in the case of following two modes: steady-state mode of ADSR in the starting process and λ-eigenvalue mode in the beam trip condition. Overall, this research provides useful insights on neutron kinetics and can boost the development of ADSRs.

Abstract As concrete and mortar materials widely used in structural engineering may suffer dynamic loadings, studies on their mechanical properties under different strain rates are of great importance. In this paper, based on splitting tests of Brazilian discs, the tensile strength and failure pattern of concrete and mortar were investigated under quasi-static and dynamic loadings with a strain rate of 1–200 s−1. It is shown that the quasi-static tensile strength of mortar is higher than that of concrete since coarse aggregates weaken the interface bonding strength of the latter. Numerical results confirmed that the plane stress hypothesis lead to a lower value tensile strength for the cylindrical specimens. With the increase of strain rates, dynamic tensile strengths of concrete and mortar significantly increase, and their failure patterns change form a single crack to multiple cracks and even fragment. Furthermore, a relationship between the dynamic increase factor and strain rate was established by using a linear fitting algorithm, which can be conveniently used to calculate the dynamic increase factor of concrete-like materials in engineering applications.

This paper proposes an impact-based micro piezoelectric energy harvesting system (PEHS) working with the frequency up-conversion mechanism. The PEHS consists of a high-frequency straight piezoelectric cantilever (SPC), a low-frequency S-shaped stainless-steel cantilever (SSC), and supporting frames. During the vibration, the frequency up-conversion behavior is realized through the impact between the bottom low-frequency cantilever and the top high-frequency cantilever. The SPC used in the system is fabricated using a new micro electromechanical system (MEMS) fabrication process for a piezoelectric thick film on silicon substrate. The output performances of the single SPC and the PEHS under different excitation accelerations are tested. In the experiment, the normalized power density of the PEHS is 0.216 μW·g−1·Hz−1·cm−3 at 0.3 g acceleration, which is 34 times higher than that of the SPC at the same acceleration level of 0.3 g. The PEHS can improve the output power under the low frequency and low acceleration scenario.

By analyzing the relationship between measured values of pressure loss in a high-pressure hose and calculated values of metal tubing pressure loss formula under the same condition, a calculation formula of pressure loss in a high-pressure hose is revised on the basis of the existing formula, and a model of calculating the circulating pressure loss in coiled tubing ultra-short radius radial drilling is established by theoretical derivation. The effects of tubing diameter, tubing length, pump delivery and fluid dynamic viscosity on each part of pressure loss in circulation system are studied by the pressure loss calculating model. The pressure loss in coiled and straight parts of 0.025 4 m (1 in) coiled tubing is about 8-10 times bigger than the pressure loss of 0.038 1 m (1.5 in) coiled tubing, and the pressure loss in high-pressure hose accounts for a large proportion in circulation system, about 86% in this study; and with drag reducer added in clear water, the pressure loss is about half of clear water pressure loss under the same condition. Key words: coiled tubing, radial drilling, high-pressure hose, circulation system, friction factor, pressure loss

Primordial germ cells (PGCs) play a crucial role in transmitting genetic information to the next-generation. In chickens, genetically edited PGCs can be propagated in vitro and subsequently transplanted into recipient embryos to produce offspring with desired genetic traits. However, during early embryogenesis, the effects of external conditions on PGC migration through the vascular system to the gonads have yet to be explored, which may affect the efficiency of preparing gene-edited chickens. In this study, we investigated the effects of hyperthermia on the biological characteristics and migration of chicken PGCs. A gonad-derived PGC line of White Leghorn (WLH) chicken was established and verified through PAS staining and immunofluorescence of PGC-specific proteins. To visually observe PGC migration in vivo, GFP-positive PGCs were prepared and locations of chimeras were validated. Cell viability, glycogen granule contents, and mRNA expression levels of pluripotency markers (NANOG and POUV), germ cell-specific markers (DAZL and CVH), and telomerase reverse transcriptase (TERT) were reduced in PGCs cultured under high temperatures (43°C for 12, 24, and 48 h). After the heat treatment of donor PGCs (43°C) or recipient embryos (39.5°C), GFP-positive PGCs in gonads were rarely observed. Taken together, our results underscore the negative effects of hyperthermia on the biological characteristics and migration of chicken PGCs, which provides valuable insights for the implementation of PGC-based gene editing techniques in chickens.

The purpose of this study was to comprehensively analyze the genetic diversity of the Pekin duck conserved population with five generations and to evaluate the effectiveness of the current conservation strategy. In total, 277 Pekin duck conserved individuals and 40 Mallards as ancestral controls were collected. Each duck was sequenced at about 10X whole-genome coverage, while over 7.4 million single nucleotide polymorphisms (SNPs) in total were detected for genetic diversity analysis. Both the expected heterozygosity and observed heterozygosity values exceeded 0.3. The genetic differentiation (FST) values ranged from 0.007 to 0.039, and the Polymorphism information content (PIC) values ranged from 0.29 to 0.34. These results indicate no significant differentiation between generations, and the genetic diversity remains high. In particular, the inbreeding coefficient has been strictly controlled and has not increased rapidly during the conservation. Overall, the inbreeding coefficient of the conserved Pekin duck population was higher than that of its wild ancestors, indicating that domestication has resulted in reduced genetic diversity. This is the first report using whole genome resequencing data to systematically evaluate the genomic dynamics across several generations in ducks. The results show that the strategy of free mating and random seed retention within sire families is effective for maintaining the genetic diversity of the conserved Pekin duck population.

Objective: To explore the association between the neutrophil-to-lymphocyte ratio (NLR) and in-hospital heart failure (HF) in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Methods: Our present study included 413 patients diagnosed with STEMI and treated with primary PCI. We performed logistic regression models to evaluate the relationship between the NLR and in-hospital HF risk in subjects diagnosed with STEMI. Results: The incidence of HF after STEMI increased significantly with increasing NLR tertiles (the incidences of the first, second, and third tertiles were 5.07 %, 13.04 %, and 23.36 %, respectively; P

Abstract Background Teratomas are a common type of germ cell tumor. However, only a few reports on their genomic constitution have been published. The study of teratomas may provide a better understanding of their stepwise differentiation processes and molecular bases, which could prove useful for the development of tissue-engineering technologies. Methods In the present study, we analyzed the copy number aberrations of nine ovarian mature cystic teratomas using array comparative genomic hybridization in an attempt to reveal their genomic aberrations. Results The many chromosomal aberrations observed on array comparative genomic hybridization analysis reveal the complex genetics of this tumor. Amplifications and deletions of large DNA fragments were observed in some samples, while amplifications of EVX2 and HOXD9-HOXD13 on 2q31.1, NDUFV1 on 11q13.2, and RPL10, SNORA70, DNASE1L1, TAZ, ATP6AP1, and GDI1 on Xq28 were found in all nine mature cystic teratomas. Conclusions Our results indicated that amplifications of these genes may play an important etiological role in teratoma formation. Moreover, amplifications of EVX2 and HOXD9-HOXD13 on 2q31.1, found on array comparative genomic hybridization, may help to explain the characteristics of teratomas in chondrogenesis and osteogenesis.

Reproductive performance is an important trait in poultry production. Traditional methods of improving reproductive traits can only use recorded information from females, making it difficult to effectively assess the reproductive potential of males. Although genomic selection is thought to remedy this shortcoming, most studies now use simulated data or one or two generations of data to assess its effects. Also, the effectiveness of genomic selection for use in the improvement of reproductive traits in ducks has hardly been reported. In this study, data from four consecutive generations of Pekin duck populations were used to assess the effect of genomic selection on reproductive trait improvement. Whole-genome resequencing was performed for genotyping, and pedigree and SNP genetic parameters were evaluated. Using the BLUP (Best Linear Unbiased Prediction), GBLUP (Genomic Best Linear Unbiased Prediction), and ssGBLUP (Single-step Genomic Best Linear Unbiased Prediction) models, we assessed selection progress for body weight at 6 weeks, age at first egg, and egg number from 25 to 44 weeks over multiple generations. Ten-fold cross-validation was used to evaluate the genomic prediction performance. The results indicated that the heritability of growth traits decreased after routine selection, while reproductive and egg quality traits maintained moderate heritability (0.2–0.4). Selection progress showed a one-day advancement in age at first egg and an increase of one egg per generation from the 13th to 15th generations. The GBLUP model performance significantly outperformed BLUP, but ssGBLUP showed minimal improvement due to comprehensive genotyping. In conclusion, this study provides crucial insights for optimizing breeding strategies and improving economic efficiency in Pekin duck breeding.

Abstract A set of high-quality pan-genomes would help identify important genes that are still hidden/incomplete in bird reference genomes. In an attempt to address these issues, we have assembled a de novo chromosome-level reference genome of the Silkie (Gallus gallus domesticus), which is an important avian model for unique traits, like fibromelanosis, with unclear genetic foundation. This Silkie genome includes the complete genomic sequences of well-known, but unresolved, evolutionarily, endocrinologically, and immunologically important genes, including leptin, ovocleidin-17, and tumor-necrosis factor-α. The gap-less and manually annotated MHC (major histocompatibility complex) region possesses 38 recently identified genes, with differentially regulated genes recovered in response to pathogen challenges. We also provide whole-genome methylation and genetic variation maps, and resolve a complex genetic region that may contribute to fibromelanosis in these animals. Finally, we experimentally show leptin binding to the identified leptin receptor in chicken, confirming an active leptin ligand-receptor system. The Silkie genome assembly not only provides a rich data resource for avian genome studies, but also lays a foundation for further functional validation of resolved genes.

Abstract Background Identifying the key factors that underlie complex traits during domestication is a great challenge for evolutionary and biological studies. In addition to the protein-coding region differences caused by variants, a large number of variants are located in the noncoding regions containing multiple types of regulatory elements. However, the roles of accumulated variants in gene regulatory elements during duck domestication and economic trait improvement are poorly understood. Results We constructed a genomics, transcriptomics, and epigenomics map of the duck genome and assessed the evolutionary forces that have been in play across the whole genome during domestication. In total, 304 (42.94%) gene promoters have been specifically selected in Pekin duck among all selected genes. Joint multi-omics analysis reveals that 218 genes (72.01%) with selected promoters are located in open and active chromatin, and 267 genes (87.83%) with selected promoters were highly and differentially expressed in domestic trait-related tissues. One important candidate gene ELOVL3, with a strong signature of differentiation on the core promoter region, is known to regulate fatty acid elongation. Functional experiments showed that the nearly fixed variants in the top selected ELOVL3 promoter in Pekin duck decreased binding ability with HLF and increased gene expression, with the overexpression of ELOVL3 able to increase lipid deposition and unsaturated fatty acid enrichment. Conclusions This study presents genome resequencing, RNA-Seq, Hi-C, and ATAC-Seq data of mallard and Pekin duck, showing that selection of the gene promoter region plays an important role in gene expression and phenotypic changes during domestication and highlights that the variants of the ELOVL3 promoter may have multiple effects on fat and long-chain fatty acid content in ducks.

Objective: To investigate the feasibility and accuracy of artificial intelligence (AI) methods of facial deidentification in hospital-recorded epileptic seizure videos, for improved patient privacy protection while preserving clinically important features of seizure semiology. Patients and Methods: Videos of epileptic seizures displaying seizure-related involuntary facial changes were selected from recordings at Taipei Veterans General Hospital Epilepsy Unit (between August 1, 2020 and February 28, 2023), and a single representative video frame was prepared per seizure. We tested 3 AI transformation models: (1) morphing the original facial image with a different male face; (2) substitution with a female face; and (3) cartoonization. Facial deidentification and preservation of clinically relevant facial detail were calculated based on: (1) scoring by 5 independent expert clinicians and (2) objective computation. Results: According to the clinician scoring of 26 facial frames in 16 patients, the best compromise between deidentification and preservation of facial semiology was the cartoonization model. A male facial morphing model was superior to the cartoonization model for deidentification, but clinical detail was sacrificed. Objective similarity testing of video data reported deidentification scores in agreement with the clinicians’ scores; however, preservation of semiology gave mixed results likely due to inadequate existing comparative databases. Conclusion: Artificial intelligence-based face transformation of medical seizure videos is feasible and may be useful for patient privacy protection. In our study, the cartoonization approach provided the best compromise between deidentification and preservation of seizure semiology.

The duck embryo fibroblast cell line CCL-141, which is currently the only commercialized duck cell line, has been underexplored in adipogenesis research. (1) Background: This study establishes an experimental protocol to induce adipogenesis in CCL-141 cells, addressing the importance of understanding gene functions in this process. (2) Methods: Chicken serum, fatty acids, insulin, and all-trans retinoic acid were used to treat CCL-141 cells, with adipogenesis confirmed by Oil Red O staining and gene expression quantification. CRISPR/Cas9 technology was applied to knockout PPARγ, and the resulting adipogenic phenotype was assessed. (3) Results: The treatments promoted adipogenesis, and the knockout of PPARγ validated the cell line’s utility for gene function studies. (4) Conclusions: CCL-141 cells are a suitable model for investigating duck adipogenesis, contributing to the understanding of regulatory factors in this biological process.

Body size is an important growth indicator in ducks and is a primary selection criterion for physical improvement. An excessively rapid growth rate in meat ducks can result in excessive body size, which may hinder subsequent processing and slaughter operations. However, only a few molecular markers related to body size have been studied in meat ducks. In this study, we performed a genome-wide association study (GWAS) to identify candidate genes and QTLs affecting body length (BL), keel bone length (KBL), neck length (NL), and breast width (BrW) in Pekin ducks (Anas platyrhynchos domestica). Our results indicate the significant SNP for NL is located within a pseudogene, whereas the significant SNP for BrW is located in an intergenic region. More importantly, our analysis identified a haplotype that was significantly associated with both BL and KBL. This haplotype, containing 48 single-nucleotide polymorphisms (SNPs), is localized within the XKR4 gene. The identification of this haplotype suggests that XKR4 may be a key candidate gene influencing BL and KBL in Pekin ducks. These findings have important implications for the breeding and genetic improvement of Pekin ducks, and provide valuable insights into the genetic architecture of body size traits in this species.

Abstract Long-term respirator users admitted to intensive care units need to be transferred to a respiratory care center (RCC) for weaning. It may cause malnutrition in critical care patients, which may manifest as a reduction in respiratory muscle mass, lower ventilatory capacity, and decreased respiratory tolerance. This study aimed to assess that if the patients’ nutritional status were improved, it could help RCC patients to wean from respirators. All participants were recruited from the RCC of a medical foundation in the city and Taipei Tzu Chi Hospital. The indicators include serum albumin level, respirator detachment index, maximum inspiratory pressure (PImax), rapid shallow breathing index, and body composition measurements. We recorded the length of hospital stay, mortality, and RCW (respiratory care ward) referral rate for these participants and analyzed the differences in relevant research indicators between those who were and weren’t weaned off. 43 of 62 patients were weaned from respirators, while 19 failed. The resuscitation rate was 54.8%. Patients with respirator weaning had a lower number of RCC admission days (23.1 ± 11.1 days) than respirator-dependent patients (35.6 ± 7.8 days, P

Egg production traits are crucial in the poultry industry, including age at first egg (AFE), egg number (EN) at different stages, and laying rate (LR). Ducks exhibit higher egg production capacity than other poultry species, but the genetic mechanisms are still poorly understood. In this study, we collected egg-laying data of 618 Peking ducks from 22 to 66 weeks of age and genotyped them by whole-genome resequencing. Genetic parameters were calculated based on SNPs, and a genome-wide association study (GWAS) was performed for these traits. The SNP-based heritability of egg production traits ranged from 0.09 to 0.54. The GWAS identified nine significant SNP loci associated with AFE and egg number from 22 to 66 weeks. These loci showed that the corresponding alleles were positively correlated with a decrease in the traits. Moreover, three potential candidate genes (ENSAPLG00020011445, ENSAPLG00020012564, TMEM260) were identified. Functional enrichment analyses suggest that specific immune responses may have a critical impact on egg production capacity by influencing ovarian function and oocyte maturation processes. In conclusion, this study deepens the understanding of egg-laying genetics in Peking duck and provides a sound theoretical basis for future genetic improvement and genomic selection strategies in poultry.

Abstract There is scarce evidence about the surgeon learning curve of acute type A aortic dissection surgery and whether the optimal procedure number exists when training a cardiovascular surgeon. A total of 704 patients with acute type A aortic dissection surgery performed by 17 junior surgeons who can identify their first career surgery from January 1, 2005, to December 31, 2018, are included. The surgeon experience volume is defined as the cumulative number of acute type A aortic dissection surgery of the surgeon since January 1, 2005. The primary outcome was in-hospital mortality. The possibility of non-linearity and cutoffs for surgeon experience volume level was explored using a restricted cubic spline model. The results revealed that more surgeon experience volume is significantly correlated to a lower in-hospital mortality rate (r = − 0.58, P = 0.010). The RCS model shows for an operator who reaches 25 cumulative volumes of acute type A aortic dissection surgery, the average in-hospital mortality rate of the patients can be below 10%. Furthermore, the longer duration from the 1st to 25th operations of the surgeon is significantly correlated to a higher average in-hospital mortality rate of the patients (r = 0.61, p = 0.045). Acute type A aortic dissection surgery has a prominent learning curve in terms of improving clinical outcomes. The findings suggest fostering high-volume surgeons at high-volume hospitals can achieve optimal clinical outcomes.

Abstract We aimed to determine whether the 14-item Mediterranean diet adherence screener (MEDAS) is suitable in Taiwan and associate the MEDAS score with the risk of prediabetes. In this cross-sectional study 346 patients were recruited between 2014 and 2019 at Taipei Tzu Chi Hospital. The MEDAS score was obtained with a 14-item MEDAS used in the PREDIMED trial. The blood glucose level is measured by fasting glucose and HbA1c. The results of the screener were analyzed for internal consistency and compared with the blood glucose level using multivariate regression models. The MEDAS score was significantly (p = 0.001) and inversely associated with both measures of blood glucose level. Adjusted data (95% CI) showed that each additional point in the MEDAS score decreases the risk of prediabetes with abnormal fasting glucose (> 100 mg/dL) level by 60% and the risk of prediabetes with abnormal HbA1c (> 5.7%) by 22.4%. Consuming at least 3 servings of legumes each week was significantly (p = 0.007) related to a lower risk of prediabetes under logistic regression. A higher score on the 14-item MEDAS screener was significantly associated with a lower risk of prediabetes.

Abstract Background Behçet’s syndrome (BS) is a rare variant vasculitis which can involve the eyes and gastrointestinal systems. However, ocular involvement rarely overlaps with intestinal lesions. This study aimed to compare the clinical characteristics and laboratory parameters of ocular BS and intestinal BS patients in China and analyze the differences between two key phenotypes to verify the heterogeneous conditions in BS patients. Methods A retrospective analysis was used to collect the demographic data, clinical characteristics, endoscopic findings, and laboratory parameters from 135 ocular BS and 174 intestinal BS patients. The Mann-Whitney U test and Pearson chi-square or continuity correction was used to analyze the differences between two groups. Results Among 916 BS patients enrolled in this study, ocular BS and intestinal BS accounted for 14.74% (135 cases) and 19.00% (174 cases), respectively. Ocular and intestinal involvements overlapped in only 7 cases (0.76%). Male gender (74.8% vs. 51.1%, P=0.00), erythema nodosum (45.9% vs. 32.2%, P=0.01), and vascular involvement (6.7% vs. 1.7%, P=0.03) were more frequent in the ocular BS group compared with the intestinal BS group. On the contrary, hematologic involvement (7.5% vs. 0.0%, P=0.00) and fever (17.8% vs. 4.4%, P=0.00) were more frequent in the intestinal BS group compared with the ocular BS group. Additionally, the inflammation markers including ESR [26.5 (16.0–41.5) vs. 9.0 (5.0–15.0) mm/H, P=0.00], CRP [14.8 (4.8–33.0) vs. 4.1 (1.6–8.3) mg/L, P=0.00], serum amyloid A [27.4 (10.8–92.3) vs. 11.3 (6.0–24.0) mg/L, P=0.00], and interleukin 6 [8.4 (1.7–18.7) vs. 1.7 (1.5–3.2) pg/mL, P=0.00] were higher in the intestinal BS group than those in the ocular BS group, respectively. Conclusions Ocular BS was more prevalent in male patients and more likely to manifest with erythema nodosum and vascular involvement, while intestinal BS tends to have fever and hematologic disorders with higher inflammation markers. Ocular BS and intestinal BS are two distinct clinical phenotypes and very rarely overlapped.

ABSTRACT: The microbiota has received plenty of attention in recent years due to its influence on host health and productivity. The striped eggs have reduced hatching performance and resulted in economic loss. The reasons are still unknown. Microbiota is one of the potentially important factors contributing to striped egg formation. This study investigates the relationship between the microbiota and striped eggs. The litter samples, feed samples, and cloacal swab samples of female ducks that produce striped eggs and normal eggs were performed for microbial diversity and composition using 16S rRNA sequencing. The results showed that there was no significant difference between feed microbiota and cloacal swab microbiota by alpha diversity, whereas, the number of microorganisms in the litter samples of female ducks that produced striped eggs was less than those of female ducks with normal eggs. There were compositional differences in litter microbiota of female ducks between the striped egg and the normal eggs. Among them, the abundance of Staphylococcus, Corynebacterium, and Brevibacterium in the litter of female ducks that produced striped eggs was significantly higher than that produced normal eggs. And these differential bacteria maybe affect the health of female ducks and cause abnormalities in the formation process of duck eggs. Therefore, the reduction of harmful bacteria may protect the reproductive health of female ducks and decrease the proportion of striped eggs. It provides an important reference to explore why female ducks produce striped eggs.

Domestic ducks are descended from the Mallard and have been bred for several purposes. Here the authors present three high-quality duck genome assemblies which recover previously missing genes and provide a rich resource of variants potentially related to domestication.

Abstract Background Behçet’s disease (BD) can involve any site of the alimentary canal. There has been research concerning intestinal BD. Nevertheless, the entire digestive tract not yet been studied extensively. Therefore, the purpose of study was to describe the prevalence, location, clinical features and possible risk factors of BD with gastrointestinal tract ulcer. Methods This was a cross-sectional observational study that included 1232 consecutive BD patients who routinely underwent endoscopy upon their wishes. The clinical symptoms, endoscopic findings, and histologic features of BD with gastrointestinal ulcer and negative Helicobacter pylori (Hp) were identified. Result We found that 22.16% (273/1232) BD patients had ulcers of the alimentary tract. At presentation, 61.54% (168/273) patients were asymptomatic. Isolated gastroduodenal involvement is an extremely usual event. The second was the pairwise combination between bowel segments, and 24 cases involved three segments at the same time. One patient suffered from total gastrointestinal tract involvement. Inflammation was the most common histopathologic feature 77.60% (142/183). The 273 BD patients with gastrointestinal ulcer were at greater risk of having archenteric symptoms (OR 0.070, P < 0.001), fever (OR 0.115, P = 0.047), high CRP (OR 0.994, P = 0.027) and BDCAF level (OR 0.590, P = 0.010). Uveitis correlates negatively with gastrointestinal involvement in BD patients (OR 3.738, P = 0.011). Conclusions BD could affect the upper gastrointestinal tract independently. Endoscopy should be conducted in all patients in whom a diagnosis of BD is entertained, especially in patients with higher CRP, disease activity and fever. While, BD patients with uveitis correlates negatively with gastrointestinal involvement.

Spin angular momentum (SAM) and orbital angular momentum (OAM) are two important fundamental degrees of freedom of light and play crucial roles in various light–matter interactions. SAM usually makes the microparticle rotate around its axis, while OAM causes orbital motion of the microparticles around the beam axis. For an optical field with only SAM, the spin-to-orbit conversion may occur under the tightly focused condition, leading to the orbital motion of probing particles. However, it is invalid for weakly focused conditions. Here, we generated an annular optical field without intrinsic OAM by weakly focusing (i.e., negligible spin-to-orbit conversion) a circularly polarized light with a linearly varying radial phase and then observed a kind of dual orbital motion of asymmetric probing particles (Janus particles) in the focal plane. The two orbital motions have opposite directions on both sides across the strongest ring of the annular optical field. In addition to the SAM, the local angular momentum (AM) density also depends on the radial intensity gradient. The radial intensity gradient has the opposite signs on both sides across the strongest ring of the annular optical field, which results in the opposite orbital motions of trapped particles. The manipulation of the local AM density and the resulting novel dual orbital effect in the absence of intrinsic OAM provide a new scene to understand the physics underlying the light–matter interaction, paving the way to some new applications involving the sorting and delivery of microparticles.

Objective According to market demand, meat duck breeding mainly includes 2 breeding directions: lean Pekin duck (LPD) and fat Pekin duck (FPD). The aim of the present study was to compare carcass and meat quality traits between 2 strains, and to provide basic data for guidelines of processing and meat quality improvement. Methods A total of 62 female Pekin ducks (32 LPDs and 30 FPDs) were slaughtered at the age of 42 days. The live body weight and carcass traits were measured and calculated. Physical properties of breast muscle were determined by texture analyzer and muscle fibers were measured by paraffin sections. The content of inosine monophosphate (IMP), intramuscular fat (IMF) and fatty acids composition were measured by high-performance liquid chromatography, Soxhlet extraction method and automated gas chromatography respectively. Results The results showed that the bodyweight of LPDs was higher than that of FPDs. FPDs were significantly higher than LPDs in subcutaneous fat thickness, subcutaneous fat weight, subcutaneous fat percentage, abdominal fat percentage and abdominal fat shear force (p0.05). The polyunsaturated fatty acid content of LPDs was significantly higher than that of FPDs (p

Establishing the dynamics model of robot and its parameters is significant for simulation analysis, control algorithm verification, and implementation of human–machine interaction. Especially under various working conditions, the errors of the calculated predicted torque of each axis have the most direct negative effect. The general robot dynamics model rarely takes the minor and complex characteristics into consideration, such as the reducer flexibility, inertia force of motor rotors, and friction. However, as the structure of collaborative robots is lighter and smaller than the ordinary industrial robots, the characteristics neglected by general dynamics models account for a relatively large amount. The above facts result in a large error in the calculation and prediction of collaborative robots analysis. To address the short comings of general robot dynamics model, a network based on long short-term memory (LSTM) in deep recurrent neural network was proposed. The network compensates the general dynamics model of a self-developed six-degree-of-freedom collaborative robot based on the consideration of gravity, Coriolis force, inertial force, and friction force. In the experiment, the nondisassembly experimental measurement combined with least-squares method was used to identify the parameters. The motor current was used to evaluate the joint torque instead of mounting an expensive and inconvenient torque sensor. The excitation trajectory based on the Fourier series was optimized. The raw experimental data were used to train the proposed LSTM network. About the accuracy of the dynamic model and the compensation method for the collaborative robot, the root-mean-square error of the calculated torque relative to the actual measured torque was used to train the network and evaluate the proposed method. The analysis and the results of the experiment show that the compensated collaborative robot dynamics model based on LSTM network displays a good prediction on the actual torque, and the root-mean-square error between predicted and actual torques is reduced from 61.8% to 78.9% compared to the traditional model, the effectiveness of the proposed error compensation policy is verified.

Abstract Background Feeding behavior traits are an essential part of livestock production. However, the genetic base of feeding behavior traits remains unclear in Pekin ducks. This study aimed to determine novel loci related to feeding behavior in Pekin ducks. Results In this study, the feeding information of 540 Pekin ducks was recorded, and individual genotype was evaluated using genotyping-by-sequencing methods. Genome-wide association analysis (GWAS) was conducted for feeding behavior traits. Overall, thirty significant (P-value

Abstract Background Intestinal Behçet’s syndrome (BS) has high morbidity and mortality rates with serious complications. The purpose of this study was to investigate the clinical characteristics and laboratory parameters of intestinal and mucocutaneous BS patients and analyze the risk factors of intestinal involvement in BS patients. Methods A retrospective analysis was used to collect the demographic data and laboratory parameters from 97 intestinal and 154 mucocutaneous BS patients. Univariate and multivariate logistic regression analyses were used to investigate the risk factors of intestinal involvement in BS patients. Results The most common clinical manifestations of first onset in intestinal BS patients were oral ulceration (100.00%), followed by genital ulcers (62.89%) and erythema nodule (28.87%), gastrointestinal lesions (28.87%), pseudofolliculitis (25.77%), fever (17.53%), arthritis (16.49%), ocular involvement (5.15%), while the least common were vascular involvement (2.06%) and hematologic involvement involvement (2.06%). The most common intestinal segment involved in intestinal BS patients was terminal ileum (30.9%), followed by ileocecal (18.6%), colon (15.5%). By univariate logistic regression analysis, gender, age at hospitalization, age of disease onset, BDCAF, T-SPOT, fever, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), leukocyte, erythrocyte, hemoglobin (HGB), neutrophil-to-lymphocyte ratio, serum amyloid A, complement 3, albumin, total cholesterol, high-density lipoprotein and interleukin 6 (IL-6) were found all risk factors of intestinal involvement in BS patients (P 10 mg/L), HGB ( 7 pg/ml) were found the independent risk factors of intestinal involvement in BS patients (all P 10 mg/L), HGB ( 7 pg/ml) being observed, it may reminds that the presence of intestinal involvement in BS patients.

By using the ray-tracing method based on geometric optics, we studied the propagating and focusing characteristics of vortex beams with a top-hat intensity distribution. An intuitive mathematical model is established for the propagation and focusing of vortex beams, revealing the mechanisms and physics underlying the spatial evolution, e.g., the dark spot formation in the center of a vortex beam, the relationship between the radius of the dark spot and the propagation distance, and the rotational angle varying with the propagation distance for an azimuthal asymmetric vortex beam. The experimental observations are consistent with theoretical predictions. The results and findings are helpful in intuitively understanding the propagation and evolution of specific vortex beams; therefore, they are of significance for explorations of the novel properties of twisted vortex beams and their applications.

Because the variational theory is the theoretical basis for many kinds of analytical or numerical methods, it is an essential but difficult task to seek explicit functional formulations whose extrema are sought by the nonlinear and complex models. By the semi-inverse method and designing trial-Lagrange functional skillfully, two different groups of variational principles are constructed for the Whitham-Broer-Kaup equations, which can model a lot of nonlinear shallow-water waves. Furthermore, by a combination of different variational formulations, new families of variational principles are established. The obtained variational principles provide conservation laws in an energy form and are proved correct by minimizing the functionals with the calculus of variations. All variational principles are firstly discovered, which can help to study the symmetries and find conserved quantities, and might find lots of applications in numerical simulation. The procedure reveals that the semi-inverse method is highly efficient and powerful, and can be extended to more other nonlinear equations.

Body weight–related traits and feeding behavior traits are important in poultry breeding and production. To investigate the heritability of feeding behavior and their genetic correlation with body weight–related traits in Pekin ducks, 5,594 Pekin ducks were selected. The information about body weight–related traits and feeding behavior from 3 to 6 wk of age were recorded by automatic electronic feeders. The heritability estimates for body weight, residual feed intake, and feeding behavior traits are relatively high (ranging from 0.29 to 0.65). We observed that total feed intake, meal feed intake, body weight at the age of 3 wk, and daily body weight gain had strong positive genetic correlations with body weight at the age of 6 wk. Moreover, body weight at the age of 3 wk also showed a positive genetic correlation with the feed conversion ratio (0.33). Total feeding time, daily feed intake, and feeding rate had significant positive phenotypic correlations with feed efficiency. However, the average interval between meals, the number of daily visits, and the number of meals all had a low genetic or phenotypic relationship with body weight and feed efficiency. In conclusion, our study revealed that body weight, residual feed intake, and feeding behavior traits were all highly heritable traits, and the selection for certain feeding behaviors could improve feed efficiency in Pekin ducks. This study is the first report about genetic parameter estimates about feeding behaviors in ducks based on large datasets and provides solid data for genetic study in ducks.

The first wave of the coronavirus disease 2019 (COVID-19) outbreak in Taiwan occurred in May 2021. The risk for and severity of this disease vary and are highly dependent on personal habits and comorbidities. Moreover, the gut microbiome, which may be affected by diet, is highly susceptible with regard to the risk and severity of infectious diseases such as COVID-19. The relationship between dietary habits, nutritional status, and the effects of these factors on the immune system in the context of a global pandemic is an extremely important topic of immediate concern. Hence, the aim of this study was to explore the effect of vegetarian and non-vegetarian diets on COVID-19 severity during the pandemic. We conducted a retrospective evaluation of 509 patients who had been diagnosed with COVID-19 at a single medical center between May 2021 and August 2021. Patients were divided into three groups according to disease severity. For patients aged ≥65 years, COVID-19 symptom severity was statistically significantly and inversely associated with the adherence to a vegetarian diet (p = 0.013). Moreover, subgroup analysis results showed that older COVID-19 patients and those with a non-vegetarian diet had a higher risk of contracting critically severe COVID-19 [adjusted odds ratio (OR) = 5.434, p = 0.005]. Further research is needed to determine the effects of dietary habits on COVID-19 risk and severity during the global pandemic.

Negative and positive emotions are the risk and protective factors for the cause and prognosis of hypertension. This study aimed to use five photoplethysmography (PPG) waveform indices and affective computing (AC) to discriminate the emotional states in patients with hypertension. Forty-three patients with essential hypertension were measured for blood pressure and PPG signals under baseline and four emotional conditions (neutral, anger, happiness, and sadness), and the PPG signals were transformed into the mean standard deviation of five PPG waveform indices. A support vector machine was used as a classifier. The performance of the classifier was verified by using resubstitution and six-fold cross-validation (CV) methods. Feature selectors, including full search and genetic algorithm (GA), were used to select effective feature combinations. Traditional statistical analyses only differentiated between the emotional states and baseline, whereas AC achieved 100% accuracy in distinguishing between the emotional states and baseline by using the resubstitution method. AC showed high accuracy rates when used with 10 waveform features in distinguishing the records into two, three, and four classes by applying a six-fold CV. The GA feature selector further boosted the accuracy to 78.97%, 74.22%, and 67.35% in two-, three-, and four-class differentiation, respectively. The proposed AC achieved high accuracy in categorizing PPG records into distinct emotional states with features extracted from only five waveform indices. The results demonstrated the effectiveness of the five indices and the proposed AC in patients with hypertension.

ABSTRACT: Peking duck is the most representative of the meat-type duck breed, and it is also one of the most popular meats in Asia. Few studies were reported on the fast assessment of duck meat quality. This study aimed to develop a fast measuring of duck fat content by using the near-infrared spectroscopy (NIRS) method. We measured 273 duck breast muscle intramuscle fat (IMF) content and spectra. Partial least-squares regression (PLSR) was used to model the fat content prediction by using the spectra in the wavelengths between 950 and 1650 nm. The best predictive abilities were obtained after the first derivative pretreatment, with coefficient of calibration (R2C) of 0.92, with coefficient of prediction (R2P) of 0.90, ratio performance to deviation (RPD) of 2.72, and ratio of error range (RER) of 15.45, for samples of 30 g duck. Results demonstrated that the near-infrared spectroscopy is a useful tool for fat content assessment of Peking duck meat.

Polarization singularities, describing the points where the state of polarization is indeterminate, reveal the polarization topology in vectorial optical fields, which include two-/three-dimensional topologies such as C-points, V-points, L-lines, Möbius strips, links, and knots. Compared with the phase singularities, it has more parameters to manipulate, which bring forth a series of novel optical phenomena and potential applications. In this Perspective, the research progress and development of polarization singularities are reviewed from the mathematical description, generation, detection, propagation dynamics, and related applications. In particular, we focused on the three-dimensional spatial propagation and the topological characteristics of polarization singularities in detail and revealed some basic fundamental physical phenomena and the novel effects of polarization singularities. We aim to touch on the key research studies in this field and provide insight into the current status and the challenges to the research studies. Finally, we outline the exciting prospects for the future that are yet to be realized.

Abstract Background Argument remains as to whether birds have lost genes compared with mammals and non-avian vertebrates during speciation. High quality-reference gene sets are necessary for precisely evaluating gene gain and loss. It is essential to explore new reference transcripts from large-scale de novo assembled transcriptomes to recover the potential hidden genes in avian genomes. Results We explored 196 high quality transcriptomic datasets from five bird species to reconstruct transcripts for the purpose of discovering potential hidden genes in the avian genomes. We constructed a relatively complete and high-quality bird transcript database (1,623,045 transcripts after quality control in five birds) from a large amount of avian transcriptomic data, and found most of the presumed missing genes (83.2%) could be recovered in at least one bird species. Most of these genes have been identified for the first time in birds. Our results demonstrate that 67.94% genes have GC content over 50%, while 2.91% genes are AT-rich (AT% > 60%). In our results, 239 (53.59%) genes had a tissue-specific expression index of more than 0.9 in chicken. The missing genes also have lower Ka/Ks values than average (genome-wide: Ka/Ks = 0.99; missing gene: Ka/Ks = 0.90; t-test = 1.25E-14). Among all presumed missing genes, there were 135 for which we did not find any meaningful orthologues in any of the 5 species studied. Conclusion Insufficient reference genome quality is the major reason for wrongly inferring missing genes in birds. Those presumably missing genes often have a very strong tissue-specific expression pattern. We show multi-tissue transcriptomic data from various species are necessary for inferring gene family evolution for species with only draft reference genomes.

Abstract Background Pekin duck products have become popular in Asia over recent decades and account for an increasing market share. However, the genetic mechanisms affecting carcass growth in Pekin ducks remain unknown. This study aimed to identify quantitative trait loci affecting body size and carcass yields in Pekin ducks. Results We measured 18 carcass traits in 639 Pekin ducks and performed genotyping using genotyping-by-sequencing (GBS). Loci-based association analysis detected 37 significant loci for the 17 traits. Thirty-seven identified candidate genes were involved in many biological processes. One single nucleotide polymorphism (SNP) (Chr1_140105435 A > T) located in the intron of the ATPase phospholipid transporting 11A gene (ATP11A) attained genome-wide significance associated with five weight traits. Eight SNPs were significantly associated with three body size traits, including the candidate gene plexin domain containing 2 (PLXDC2) associated with breast width and tensin 3 (TNS3) associated with fossil bone length. Only two SNPs were significantly associated with foot weight and four SNPs were significantly associated with heart weight. In the gene-based analysis, three genes (LOC101791418, TUBGCP3 (encoding tubulin gamma complex-associated protein 3), and ATP11A) were associated with four traits (42-day body weight, eviscerated weight, half-eviscerated weight, and leg muscle weight percentage). However, no loci were significantly associated with leg muscle weight in this study. Conclusions The novel results of this study improve our understanding of the genetic mechanisms regulating body growth in ducks and thus provide a genetic basis for breeding programs aimed at maximizing the economic potential of Pekin ducks.

Visualization of simulated crop growth and development is of significant interest to crop research and production. This study aims to address the phenomenon of organs cross-drawing by developing a method of collision detection for improving vivid 3D visualizations of virtual wheat crops. First, the triangular data of leaves are generated with the tessellation of non-uniform rational B-splines surfaces. Second, the bounding volumes (BVs) and bounding volume hierarchies (BVHs) of leaves are constructed based on the leaf morphological characteristics and the collision detection of two leaves are performed using the Separating Axis Theorem. Third, the detecting effect of the above method is compared with the methods of traditional BVHs, Axis-Aligned Bounding Box (AABB) tree, and Oriented Bounding Box (OBB) tree. Finally, the BVs of other organs (ear, stem, and leaf sheath) in virtual wheat plant are constructed based on their geometric morphology, and the collision detections are conducted at the organ, individual and population scales. The results indicate that the collision detection method developed in this study can accurately detect collisions between organs, especially at the plant canopy level with high collision frequency. This collision detection-based virtual crop visualization method could reduce the phenomenon of organs cross-drawing effectively and enhance the reality of visualizations.