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Aphis gossypii Glover (Hemiptera: Aphididae) is a significant pest of Capsicum annuum (Solanales: Solanaceae) and exhibits intraspecific differentiation within populations. To investigate the adaptability of Hap3 and Hap17 A. gossypii to various C. annuum varieties, including ‘Lvzhou101’ (LZ), ‘Lashen’ (LA), ‘Saierweilvtianjiao’ (SE), ‘Haimaihongri’ (HM), ‘Chaotianjiao’ (CT), and ‘Luosijiangjun’ (LS), we employed life tables to analyse growth and population parameters post-feeding and conducted petri dish host choice experiments to assess the host plant preference of A. gossypii. Survival rates of A. gossypii varied significantly across C. annuum varieties. Notably, Hap3 and Hap17 thrived on ‘LZ’ but failed to establish populations on ‘LA’. The net reproductive rate (R0), average generation time (T), and intrinsic rate of increase (rm) differed markedly between Hap3 and Hap17 across C. annuum varieties. Feeding on ‘LZ’ resulted in a significantly higher R0 value (26.49) for Hap3 relative to other varieties. The T (7.60 days) and rm (0.27) values for Hap3 on ‘SE’ were superior to those observed on other C. annuum varieties. These findings indicate that ‘SE’ is the optimal host for Hap3 growth, while ‘LZ’ best supports Hap17. Both haplotypes exhibited the lowest adaptability to ‘LA’. Therefore, the utilisation capacity of A. gossypii populations on C. annuum demonstrates differentiation, and the resistance levels among C. annuum varieties to A. gossypii vary. This differentiation can inform targeted management strategies for aphid infestations on pepper crops.
Let $[a_1(x),a_2(x),\ldots ,a_n(x),\ldots ]$ be the continued fraction expansion of $x\in [0,1)$ and $q_n(x)$ be the denominator of its nth convergent. The irrationality exponent and Khintchine exponent of x are respectively defined by
We study the multifractal spectrum of the irrationality exponent and the Khintchine exponent for continued fractions with nondecreasing partial quotients. For any $v>2$, we completely determine the Hausdorff dimensions of the sets $\{x\in [0,1): a_1(x)\leq a_2(x)\leq \cdots , \overline {v}(x)=v\}$ and
To address the issues of low positioning accuracy and weak robustness of prior visual simultaneous localization and mapping (VSLAM) systems in dynamic environments, a semantic VSLAM (Sem-VSLAM) approach based on deep learning is proposed in this article. The proposed Sem-VSLAM algorithm adds semantic segmentation threads in parallel based on the open-source ORB-SLAM2’s visual odometry. First, while extracting the ORB features from an RGB-D image, the frame image is semantically segmented, and the segmented results are detected and repaired. Then, the feature points of dynamic objects are eliminated by using semantic information and motion consistency detection, and the poses are estimated by using the remaining feature points after the dynamic feature elimination. Finally, a 3D point cloud map is constructed by using tracking information and semantic information. The experiment uses Technical University of Munich public data to show the usefulness of the Sem-VSLAM algorithm. The experimental results show that the Sem-VSLAM algorithm can reduce the absolute trajectory error and relative attitude error of attitude estimation by about 95% compared to the ORB-SLAM2 algorithm and by about 14% compared to the VO-YOLOv5s in a highly dynamic environment and the average time consumption of tracking each frame image reaches 61 ms. It is verified that the Sem-VSLAM algorithm effectively improves the robustness and positioning accuracy in high dynamic environment and owning a satisfying real-time performance. Therefore, the Sem-VSLAM has a better mapping effect in a highly dynamic environment.
The existing single-mode posture adjustment equipment for solar wing docking is only suitable for a limited number of satellite dimensions; it could not meet the diverse development trends of satellite models. The working range requirements are different when different-sized satellites dock with the solar wing, and the docking process is divided into two stages in this paper. While the DOFs required for the two stages are different, a movable heavy-load reconfigurable redundant posture adjustment platform (RrPAP) with dual motion modes is proposed in this paper. The RrPAP consists of a wheeled mobile platform and a reconfigurable parallel posture adjustment mechanism (PAM). The micro-motion PAM limb types are synthesized, and the comprehensive load-bearing index is proposed to select the mechanism types for heavy-load conditions. A decentralized four-limb six-degree-of-freedom (6-DOF) parallel micro-motion PAM is designed. In the macro-motion stage, for the PAM to still have a defined motion after being released from ground constraints, a serial coupling sub-chain is designed between adjacent limbs to restrict relative movement between them. A type synthesis method for symmetrically coupled mechanisms based on mechanism decoupling and motion distribution is proposed. Four types of symmetrically coupled mechanisms with multi-loop consisting of serial coupling sub-chains are synthesized by using this method. The feasibility of the proposed method is demonstrated through an example using the constraint synthesis method based on screw theory. This work provides a foundation for subsequent refinement and expansion of type synthesis theories and the selection of new types of mechanisms.
This paper retrospectively analysed the prevalence of macrolide-resistant Mycoplasma pneumoniae (MRMP) in some parts of China. Between January 2013 and December 2019, we collected 4,145 respiratory samples, including pharyngeal swabs and alveolar lavage fluid. The highest PCR-positive rate of M. pneumoniae was 74.5% in Beijing, the highest resistance rate was 100% in Shanghai, and Gansu was the lowest with 20%. The highest PCR-positive rate of M. pneumoniae was 74.5% in 2013, and the highest MRMP was 97.4% in 2019; the PCR-positive rate of M. pneumoniae for adults in Beijing was 17.9% and the MRMP was 10.48%. Among the children diagnosed with community-acquired pneumonia (CAP), the PCR-positive and macrolide-resistant rates of M. pneumoniae were both higher in the severe ones. A2063G in domain V of 23S rRNA was the major macrolide-resistant mutation, accounting for more than 90%. The MIC values of all MRMP to erythromycin and azithromycin were ≥ 64 μg/ml, and the MICs of tetracycline and levofloxacin were ≤ 0.5 μg/ml and ≤ 1 μg/ml, respectively. The macrolide resistance varied in different regions and years. Among inpatients, the macrolide-resistant rate was higher in severe pneumonia. A2063G was the common mutation, and we found no resistance to tetracycline and levofloxacin.
Head-up tilt test (HUTT) is an important tool in the diagnosis of pediatric vasovagal syncope. This research will explore the relationship between syncopal symptoms and HUTT modes in pediatric vasovagal syncope.
Methods:
A retrospective analysis was performed on the clinical data of 2513 children aged 3–18 years, who were diagnosed with vasovagal syncope, from Jan. 2001 to Dec. 2021 due to unexplained syncope or pre-syncope. The average age was 11.76 ± 2.83 years, including 1124 males and 1389 females. The patients were divided into the basic head-up tilt test (BHUT) group (596 patients) and the sublingual nitroglycerine head-up tilt test (SNHUT) group (1917 patients) according to the mode of positive HUTT at the time of confirmed pediatric vasovagal syncope.
Results:
(1) Baseline characteristics: Age, height, weight, heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and composition ratio of syncope at baseline status were higher in the BHUT group than in the SNHUT group (all P < 0.05). (2) Univariate analysis: Age, height, weight, HR, SBP, DBP, and syncope were potential risk factors for BHUT positive (all P < 0.05). (3) Multivariate analysis: syncope was an independent risk factor for BHUT positive, with a probability increase of 121% compared to pre-syncope (P<0.001).
Conclusion:
The probability of BHUT positivity was significantly higher than SNHUT in pediatric vasovagal syncope with previous syncopal episodes.
Using comprehensive account-level data, we separate Chinese retail investors into 5 groups and document strong heterogeneity in trading dynamics and performances. Retail investors with smaller account sizes cannot predict future returns correctly, display daily momentum patterns, fail to process public news, and show overconfidence and gambling preferences, while retail investors with larger account balances predict future returns correctly, display contrarian patterns, and incorporate public news in trading. Using performance measures established in previous literature, we find that smaller retail investors suffer from poor stock selection abilities and trading costs, while large retail investors’ stock selection abilities are offset by trading costs.
Findings from observational studies have suggested a possible association between dietary inflammatory index (DII) and risk of gestational diabetes mellitus (GDM) and preeclampsia (PE). However, the results of these studies were inconclusive. A systematic review and meta-analysis was carried out to illuminate this association. Systematic literature search was conducted in PubMed, Web of Science, Cochrane Library, EMBASE, Scopus and other databases from inception until January 2023. The qualities of included studies were assessed using the Newcastle–Ottawa scale. Nine studies (seven cohort, two case–control) were included in the meta-analysis, including 11 423 participants from five different countries. The meta-analysis indicated that a 1-unit increase in the DII score, representing pro-inflammatory diet, was associated with 13 % higher risk of GDM (OR = 1·13; 95 % CI 1·02, 1·25, I2 = 68·4 %, P = 0·004) and 24 % higher risk of PE (OR = 1·24; 95 % CI 1·14, 1·35, I2 = 52·0 %, P = 0·125). Subgroup analysis found that this association was evident among studies with Chinese populations (OR = 1·16; 95 % CI 1·06, 1·28) and studies with mid pregnancy (OR = 1·20; 95 % CI 1·07, 1·34). The findings indicate that pro-inflammatory diet can increase the risk of GDM and PE. Considering some limitations in this study, more studies are needed to verify this association.
In this paper, a new over-constrained parallel driving mechanism (PDM) with planar sub-closed chains is proposed. First, the number of over-constraints on the PDM is calculated. Then, an analysis is conducted as to the kinematics of the hybrid manipulator, including positions, velocities, and accelerations of all bodies. Furthermore, the Newton–Euler approach is taken to deduce the kinematic formula of each link and the formula of inertial force at the center of mass. However, it remains difficult to solve the equation since the number of equations is smaller than that of unknown variables. To solve this problem, the screw theory is applied in the present study to analyze the cause of over-constraints, with the link’s elastic deformation introduced as the supplement of deformation compatibility equations. Moreover, the actuation forces and constrained forces/moments are calculated simultaneously. Finally, the dynamic model is verified through simulation and experimentation. The proposed modeling approach provides a fundamental basis for the structural optimization and friction force computation of the over-constrained PDM.
In this paper, we apply standard zooarchaeological methods and novel osteological approaches to analyse faunal remains from five Middle–Late Holocene sites in the southern Tibetan Plateau (STP). Framed by direct radiocarbon dates on taxonomically classified bioarchaeological remains and compared with published palaeoclimate data, our findings revealed a three-stage process of agro-pastoral development in the STP ca. 5.5 to 1.0 ka. In the first phase, habitation was restricted to the lower southeastern part of the plateau and human subsistence essentially based on foraging and low-level pig–millet farming. With the onset of colder and drier climatic conditions ca. 3.8 ka, the study area witnessed a growing human presence at higher elevations in its central and western parts, together with a shift towards bovid husbandry and barley cultivation, that is, agricultural practices that originated in west Asia; these were likely introduced to the STP following the eastern margin of the TP and/or arrived by sub-Himalayan transfer. Climate and ecological degradation might have contributed to the decline of local game in favour of cold-and-dry-tolerant pastoral livestock and crops. Our work shows that Middle–Late Holocene climate change, ecological change, human subsistence shifts, and prehistoric cultural transmissions are intimately connected.
In recent years, bat-associated pathogens, such as 2019 novel coronavirus, have been ravaging the world, and ectoparasites of bats have received increasing attention. Penicillidia jenynsii is a member of the family Nycteribiidae which is a group of specialized ectoparasites of bats. In this study, the complete mitochondrial genome of P. jenynsii was sequenced for the first time and a comprehensive phylogenetic analysis of the superfamily Hippoboscoidea was conducted. The complete mitochondrial genome of P. jenynsii is 16 165 base pairs (bp) in size, including 13 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region. The phylogenetic analysis based on 13 PCGs of the superfamily Hippoboscoidea known from the NCBI supported the monophyly of the family Nycteribiidae, and the family Nycteribiidae was a sister group with the family Streblidae. This study not only provided molecular data for the identification of P. jenynsii, but also provided a reference for the phylogenetic analysis of the superfamily Hippoboscoidea.
We aimed to investigate the association of metabolic obesity phenotypes with all-cause mortality risk in a rural Chinese population. This prospective cohort study enrolled 15 704 Chinese adults (38·86 % men) with a median age of 51·00 (interquartile range: 41·00–60·00) at baseline (2007–2008) and followed up during 2013–2014. Obesity was defined by waist circumference (WC: ≥ 90 cm for men and ≥ 80 cm for women) or waist-to-height ratio (WHtR: ≥ 0·5). The hazard ratio (HR) and 95 % CI for the risk of all-cause mortality related to metabolic obesity phenotypes were calculated using the Cox hazards regression model. During a median follow-up of 6·01 years, 864 deaths were identified. When obesity was defined by WC, the prevalence of participants with metabolically healthy non-obesity (MHNO), metabolically healthy obesity (MHO), metabolically unhealthy non-obesity (MUNO) and metabolically unhealthy obesity (MUO) at baseline was 12·12 %, 2·80 %, 41·93 % and 43·15 %, respectively. After adjusting for age, sex, alcohol drinking, smoking, physical activity and education, the risk of all-cause mortality was higher with both MUNO (HR = 1·20, 95 % CI 1·14, 1·26) and MUO (HR = 1·20, 95 % CI 1·13, 1·27) v. MHNO, but the risk was not statistically significant with MHO (HR = 0·99, 95 % CI 0·89, 1·10). This result remained consistent when stratified by sex. Defining obesity by WHtR gave similar results. MHO does not suggest a greater risk of all-cause mortality compared to MHNO, but participants with metabolic abnormality, with or without obesity, have a higher risk of all-cause mortality. These results should be cautiously interpreted as the representation of MHO is small.
To date, empirical research exploring the complex mechanisms of when and how information seeking from supervisor affects newcomers' task-related outcomes remains in its infancy. With a sample of 394 newcomers and their supervisors, drawing on the conservation of resources theory and professional image construction theory, we proposed and confirmed two paradoxical paths regarding perceptions of professional image construction – concern about impairing competence-image and confidence in improving commitment-image – that connect newcomers' information seeking from supervisor with their emotional exhaustion during socialization and ultimately can elevate and degrade their task-related outcomes, respectively. In addition, we found that supervisors' favorable feedback weakened the relationship between information seeking from supervisor and competence-image impairment concern, whereas it strengthened the linkage between information seeking and commitment-image improvement confidence. This study thus provides a more comprehensive picture for scholars and practitioners.
Reaction null space (RNS) planning and control of a planar three-link space manipulator’s pregrasping a spinning target are studied. First, the Lagrange dynamic model of the manipulator was established. Second, the RNS motion planning algorithm was derived, and the vector norm constraint algorithm of RNS planning was addressed to ensure certain joint angular acceleration constraints were satisfied. Furthermore, an augmented adaptive sliding mode controller based on time delay estimation (TDE) was proposed. This controller estimated the unknowns of the system by TDE technology, in which accurate and complete dynamics were not required, and an adaptive TDE was introduced to decrease the estimation errors and avoid serious chattering. Finally, numerical simulations were carried out to verify the effectiveness of the proposed RNS planning and control algorithm.
We consider a two-stage submodular maximization problem subject to a cardinality constraint and k matroid constraints, where the objective function is the expected difference of a nonnegative monotone submodular function and a nonnegative monotone modular function. We give two bi-factor approximation algorithms for this problem. The first is a deterministic $\left( {{1 \over {k + 1}}\left( {1 - {1 \over {{e^{k + 1}}}}} \right),1} \right)$-approximation algorithm, and the second is a randomized $\left( {{1 \over {k + 1}}\left( {1 - {1 \over {{e^{k + 1}}}}} \right) - \varepsilon ,1} \right)$-approximation algorithm with improved time efficiency.
To investigate the association between the Metabolic Score for Visceral Fat (METS-VF) and risk of type 2 diabetes mellitus (T2DM) and compare the predictive value of the METS-VF for T2DM incidence with other obesity indices in Chinese people. A total of 12 237 non-T2DM participants aged over 18 years from the Rural Chinese Cohort Study of 2007–2008 were included at baseline and followed up during 2013–2014. The cox proportional hazards regression was used to calculate hazard ratios (HR) and 95 % CI for the association between baseline METS-VF and T2DM risk. Restricted cubic splines were used to model the association between METS-VF and T2DM risk. Area under the receiver operating characteristic curve (AUC) analysis was used to evaluate the ability of METS-VF to predict T2DM incidence. During a median follow-up of 6·01 (95 % CI 5·09, 6·06) years, 837 cases developed T2DM. After adjusting for potential confounding factors, the adjusted HR for the highest v. lowest METS-VF quartile was 5·97 (95 % CI 4·28, 8·32), with a per 1-sd increase in METS-VF positively associated with T2DM risk. Positive associations were also found in the sensitivity and subgroup analyses, respectively. A significant nonlinear dose–response association was observed between METS-VF and T2DM risk for all participants (Pnonlinearity = 0·0347). Finally, the AUC value of METS-VF for predicting T2DM was largest among six indices. The METS-VF may be a reliable and applicable predictor of T2DM incidence in Chinese people regardless of sex, age or BMI.
Few studies have been conducted to investigate the association of kidney function decline with the trajectories of homocysteine (Hcy) over time, using repeated measurements. We aimed to investigate the association of kidney function with changes in plasma Hcy levels over time. Data were collected from the Rugao Longevity and Ageing Study. In detail, plasma Hcy and creatinine levels were measured in both waves (waves 2, 3 and 4) during the 3·5-year follow-up (n 1135). Wave 2 was regarded as the baseline survey. The estimated glomerular filtration rate (eGFR) was calculated based on creatinine. Subjects were categorised into four groups according to quartiles of eGFR at baseline. Linear mixed-effect models were used to investigate the association of eGFR with subsequent plasma Hcy levels. The mean eGFR at baseline was 90·84 (sd 11·42) ml/min per 1·73 m2. The mean plasma Hcy level was 14·09 (sd 6·82) at baseline and increased to 16·28 (sd 8·27) and 17·36 (sd 10·39) μmol/l during follow-ups. In the crude model, the interaction between time and eGFR at baseline was significant (β = −0·02, 95 % CI −0·02, −0·01, P = 0·002). After adjusting for confounding factors, a significant relationship remained (β = −0·02, 95 % CI −0·02, −0·01, P = 0·003), suggesting that kidney function decline at baseline was associated with a faster increase in Hcy levels. Kidney function decline is associated with a more pronounced increase in plasma Hcy levels. Further studies with longer follow-up periods and larger sample sizes are needed to validate our findings.
The impact of baseline hypertension status on the BMI–mortality association is still unclear. We aimed to examine the moderation effect of hypertension on the BMI–mortality association using a rural Chinese cohort.
Design:
In this cohort study, we investigated the incident of mortality according to different BMI categories by hypertension status.
Setting:
Longitudinal population-based cohort.
Participants:
17 262 adults ≥18 years were recruited from July to August of 2013 and July to August of 2014 from a rural area in China.
Results:
During a median 6-year follow-up, we recorded 1109 deaths (610 with and 499 without hypertension). In adjusted models, as compared with BMI 22–24 kg/m2, with BMI ≤ 18, 18–20, 20–22, 24–26, 26–28, 28–30 and >30 kg/m2, the hazard ratios for mortality in normotensive participants were 1·92 (95% CI 1·23, 3·00), 1·44 (95% CI 1·01, 2·05), 1·14 (95% CI 0·82, 1·58), 0·96 (95% CI 0·70, 1·31), 0·96 (95% CI 0·65, 1·43), 1·32 (95% CI 0·81, 2·14) and 1·32 (95% CI 0·74, 2·35), respectively, and in hypertensive participants were 1·85 (95% CI 1·08, 3·17), 1·67 (95% CI 1·17, 2·39), 1·29 (95% CI 0·95, 1·75), 1·20 (95% CI 0·91, 1·58), 1·10 (95% CI 0·83, 1·46), 1·10 (95% CI 0·80, 1·52) and 0·61 (95% CI 0·40, 0·94), respectively. The risk of mortality was lower in individuals with hypertension with overweight or obesity v. normal weight, especially in older hypertensives (≥60 years old). Sensitivity analyses gave consistent results for both normotensive and hypertensive participants.
Conclusions:
Low BMI was significantly associated with increased risk of all-cause mortality regardless of hypertension status in rural Chinese adults, but high BMI decreased the mortality risk among individuals with hypertension, especially in older hypertensives.
Global warming increases the risk of pests and weeds before wintering, and decreases the grain yield of winter wheat. Therefore, the sowing date should be delayed properly. But the variety of winter wheat that can adapt to late sowing remains unclear. Here, we selected two winter wheat cultivars and evaluated four sowing date treatments on 1 October (early sowing), 8 (normal sowing), 15 (late sowing) and 22 (latest sowing) over two wheat-growing seasons at the experimental Station of Shandong Agricultural University (35°96′N, 117°06′E), Daiyue District, Taian, Shandong, China. We examined the effects of sowing date on a few traits, and found that, compared with normal sowing, though spike number decreased, grain yield was maintained above 9300 kg/ha under late and latest sowing. The main reason was that the more accumulated N from jointing to anthesis resulted in a higher grain number per spike. The higher net photosynthetic rate after anthesis, through optimizing N distribution in the canopy and increasing Rubisco content of flag leaves, improved dry matter accumulation rate and contribution ratio of vegetative organs, ultimately, ensured consistent grain weight. The grain yield of high-tillering winter wheat cultivars decreased from 9370 to 8346 kg/ha. The main reason was that spike number, accumulated N from jointing to anthesis and net photosynthetic rate decreased significantly, which reduced the dry matter accumulation rate, and only satisfied less grains to achieve consistent grain weight. Therefore, low-tillering winter wheat cultivars are more adaptable to late sowing, and can reduce the harm of global warming.