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The stress field induced by an edge dislocation or a point force located near a coated triangle-like hole in an infinite plate is provided in this paper. Based on the method of analytical continuation and the technique of conformal mapping in conjunction with the alternation technique, a series solution for the displacement and stresses in the coating layer and the matrix is obtained analytically. Examples for the interaction between an edge dislocation and a coated triangle-like hole for various material constant combinations, coating thicknesses and shape factors are discussed. The analysis discovers that the so-called trapping mechanism of dislocations is more likely to exist near a coated triangle-like hole. The result shows that the dislocation will first be repelled by the coating layer and then attracted by a hole when the coating layer is slightly stiffer than the matrix. However, when the coating layer is sufficiently thin, the dislocation will always be attracted by a hole even the coating layer is stiffer than the matrix.
Seasonal influenza virus epidemics have a major impact on healthcare systems. Data on population susceptibility to emerging influenza virus strains during the interepidemic period can guide planning for resource allocation of an upcoming influenza season. This study sought to assess the population susceptibility to representative emerging influenza virus strains collected during the interepidemic period. The microneutralisation antibody titers (MN titers) of a human serum panel against representative emerging influenza strains collected during the interepidemic period before the 2018/2019 winter influenza season (H1N1-inter and H3N2-inter) were compared with those against influenza strains representative of previous epidemics (H1N1-pre and H3N2-pre). A multifaceted approach, incorporating both genetic and antigenic data, was used in selecting these representative influenza virus strains for the MN assay. A significantly higher proportion of individuals had a ⩾four-fold reduction in MN titers between H1N1-inter and H1N1-pre than that between H3N2-inter and H3N2-pre (28.5% (127/445) vs. 4.9% (22/445), P < 0.001). The geometric mean titer (GMT) of H1N1-inter was significantly lower than that of H1N1-pre (381 (95% CI 339–428) vs. 713 (95% CI 641–792), P < 0.001), while there was no significant difference in the GMT between H3N2-inter and H3N2-pre. Since A(H1N1) predominated the 2018–2019 winter influenza epidemic, our results corroborated the epidemic subtype.
Better understanding of interplay among symptoms, cognition and functioning in first-episode psychosis (FEP) is crucial to promoting functional recovery. Network analysis is a promising data-driven approach to elucidating complex interactions among psychopathological variables in psychosis, but has not been applied in FEP.
This study employed network analysis to examine inter-relationships among a wide array of variables encompassing psychopathology, premorbid and onset characteristics, cognition, subjective quality-of-life and psychosocial functioning in 323 adult FEP patients in Hong Kong. Graphical Least Absolute Shrinkage and Selection Operator (LASSO) combined with extended Bayesian information criterion (BIC) model selection was used for network construction. Importance of individual nodes in a generated network was quantified by centrality analyses.
Our results showed that amotivation played the most central role and had the strongest associations with other variables in the network, as indexed by node strength. Amotivation and diminished expression displayed differential relationships with other nodes, supporting the validity of two-factor negative symptom structure. Psychosocial functioning was most strongly connected with amotivation and was weakly linked to several other variables. Within cognitive domain, digit span demonstrated the highest centrality and was connected with most of the other cognitive variables. Exploratory analysis revealed no significant gender differences in network structure and global strength.
Our results suggest the pivotal role of amotivation in psychopathology network of FEP and indicate its critical association with psychosocial functioning. Further research is required to verify the clinical significance of diminished motivation on functional outcome in the early course of psychotic illness.
With the aims of overcoming the limitations of the existing basic flow model derived from an axisymmetric generating body and extending the aerodynamic design method of the airframe/inlet integrated waverider vehicle, this study develops an upgraded basic flow model derived from an axisymmetric shock wave. It then upgrades the design method for airframe/inlet integration of an air-breathing hypersonic waverider vehicle, which is termed the ‘full-waverider vehicle’ in this study. In this paper, first, the design principle and method for the upgraded full-waverider vehicle derived from an axisymmetric basic shock wave are described in detail. Second, an upgraded basic flow model that accounts for both internal and external flows is derived from an axisymmetric basic shock wave by use of both the streamline tracing method and the method of characteristics (MOC). Third, the upgraded full-waverider vehicle is developed from the upgraded basic flow model by the streamline tracing method. Fourth, the design theories and methodologies of both the upgraded basic flow model and the upgraded full-waverider vehicle are validated by a numerical computation method. Finally, the aerodynamic performances and viscous effects of both the upgraded basic flow model and the upgraded full-waverider vehicle are analysed by numerical computation. The obtained results show that the upgraded basic flow model and aerodynamic design method are effective for the design of the airframe/inlet integration of an air-breathing hypersonic waverider vehicle.
Optimizing the dietary calcium (Ca) level is essential to maximize the eggshell quality, egg production and bone formation in poultry. This study aimed to establish the Ca requirements of egg-type duck breeders from 23 to 57 weeks of age on egg production, eggshell, incubation, tibial, plasma and ovary-related indices, as well as the expression of matrix protein-related genes. Totally, 450 Longyan duck breeders aged 21 weeks of age were allotted randomly into five treatments, each with six replicates of 15 individually caged birds. The data collection started from 23 weeks of age and continued over the following 35 weeks. The five groups corresponded to five dietary treatments containing either 2.8%, 3.2%, 3.6%, 4.0% or 4.4% Ca. The tested dietary Ca levels increased (linear, P <0.01) egg production and egg mass, and linearly improved (P <0.01) the feed conversion ratio (FCR). Increasing the dietary Ca levels from 2.8% to 4.4% increased (P <0.01) the eggshell thickness and eggshell content. The tested Ca levels showed a quadratic effect on eggshell thickness and ovarian weight (P <0.01); the highest values were obtained with the Ca levels 4.0% and 3.6%, respectively. Dietary Ca levels affected the small yellow follicles (SYF) number and SYF weight/ovarian weight, and the linear response (P <0.01) was significant vis-à-vis SYF number. In addition, dietary Ca levels increased (P <0.05) the tibial dry weight, breaking strength, mineral density and ash content. Plasma and tibial phosphorus concentration exhibited a quadratic (P <0.01) response to dietary Ca levels. Plasma calcitonin concentration linearly (P <0.01) increased as dietary Ca levels increased. The relative expression of carbonic anhydrase 2 in the uterus rose (P <0.01) with the increment of dietary Ca levels, and the highest value was obtained with 3.2% Ca. In conclusion, Longyan duck breeders fed a diet with 4.0% Ca had superior eggshell and tibial quality, while those fed a diet with 3.6% Ca had the heaviest ovarian weights. The regression model indicated that the dietary Ca levels 3.86%, 3.48% and 4.00% are optimal levels to obtain maximum eggshell thickness, ovarian weight and tibial mineral density, respectively.
The Pain Catastrophizing Scale (PCS) measures three aspects of catastrophic cognitions about pain—rumination, magnification, and helplessness. To facilitate assessment and clinical application, we aimed to (a) develop a short version on the basis of its factorial structure and the items’ correlations with key pain-related outcomes, and (b) identify the threshold on the short form indicative of risk for depression.
Social centers for older people.
664 Chinese older adults with chronic pain.
Besides the PCS, pain intensity, pain disability, and depressive symptoms were assessed.
For the full scale, confirmatory factor analysis showed that the hypothesized 3-factor model fit the data moderately well. On the basis of the factor loadings, two items were selected from each of the three dimensions. An additional item significantly associated with pain disability and depressive symptoms, over and above these six items, was identified through regression analyses. A short-PCS composed of seven items was formed, which correlated at r=0.97 with the full scale. Subsequently, receiver operating characteristic (ROC) curves were plotted against clinically significant depressive symptoms, defined as a score of ≥12 on a 10-item version of the Center for Epidemiologic Studies-Depression Scale. This analysis showed a score of ≥7 to be the optimal cutoff for the short-PCS, with sensitivity = 81.6% and specificity = 78.3% when predicting clinically significant depressive symptoms.
The short-PCS may be used in lieu of the full scale and as a brief screen to identify individuals with serious catastrophizing.
Life-history theory predicts a trade-off between the juvenile growth rate and adult traits related to survival. However, this hypothesized negative correlation is difficult to test robustly because many trade-offs are mild, and environmental variables, such as changes in nutrient availability, can ameliorate the trade-off or make it more pronounced. Thus, it is reasonable to expect that the expression of the trade-off can be condition-dependent. In the present study, we first examined the pre-adult life-history traits of the cotton bollworm, Helicoverpa armigera, collected from northern, central, and southern China at different temperatures. We found that the northern China population has a significantly shorter pre-adult developmental time and higher growth rate than the southern China population as a result of adaptation to the decreased seasonal length. Then, we tested for a trade-off between the juvenile growth rate and adult lifespan in different temperature and nutrient conditions. We found a negative relationship between juvenile growth rate and adult lifespan under starvation or desiccation conditions; however, a continuous supply of sugar can diminish or obviate the apparent negative relationship, in which the adult lifespan did not show a significant difference in most of the comparisons. These results suggested a resource-mediated trade-off may exist between juvenile growth rate and adult lifespan. However, the adult size may have some positive effect on the lifespan under starvation and desiccation conditions, which may affect the expression of trade-off.
In the recent years, the development of wind turbines has been so hectic in Taiwan. The design of the turbine blades directly impacts power effectiveness. In this study, the effects of manufacturing parameters and environmental factors on the mechanical properties of carbon fiber/epoxy composites that are used in turbine blades are discussed. Parameters of the manufacturing process affect the mechanical properties. Carbon composites made by a different numbers of layers are tested on various aspects of performance such as mechanical strength and corrosion resistance.
To investigate the effects of soybean isoflavone (SI) on immunity in infectious bursal disease virus (IBDV)-infected broilers, chicks were fed the same basal diet supplemented with 0 (non-infected control), 0 (infected control), 10, 20 or 40 mg/kg SI for 44 days. At 21 days old, chickens were inoculated with bursal infectious dose causing 50% morbidity of the IBDV BC 6/85 strain by the eye-drop and nasal route (except for non-infected controls). Results showed that, over 1–23 days post-infection (dpi), there was a significant interaction between SI supplementation level and time: high-level SI supplementation increased peripheral T lymphocyte proliferation, percentages of CD3+, CD4+ and CD8+ T lymphocytes, CD4+ to CD8+ ratio, serum concentrations of IgA, IgM and IgG, and IBDV antibody titres. Except for serum IgA and IgM, these variables increased over time with far higher values at 23 dpi than earlier. Compared with non-infected controls, IBDV inoculation decreased peripheral T lymphocyte proliferation at 3 dpi, percentages of CD3+, CD4+ and CD8+ T lymphocytes, and serum IgG, IgM concentration at 23 dpi, and increased IBDV antibody titres at 7, 15 and 23 dpi. Supplemental SI quadratically increased peripheral T lymphocyte proliferation, CD4+ to CD8+ ratio and serum IgA concentration at 3 dpi, percentages of CD3+, CD4+ and CD8+ T lymphocytes at 3 and 23 dpi, and serum IgM concentration and IBDV antibody titres at 23 dpi. These results indicate that dietary SI improved cellular and humoral immunity of IBDV-infected birds and may enhance resistance of Yellow-feathered broilers to infectious diseases.
Wave loading on marine structures is the major external force to be considered in the design of such structures. The accurate prediction of the nonlinear high-order components of the wave loading has been an unresolved challenging problem. In this paper, the nonlinear harmonic components of hydrodynamic forces on a bottom-mounted vertical cylinder are investigated experimentally. A large number of experiments were conducted in the Danish Hydraulic Institute shallow water wave basin on the cylinder, both on a flat bed and a sloping bed, as part of a European collaborative research project. High-quality data sets for focused wave groups have been collected for a wide range of wave conditions. The high-order harmonic force components are separated by applying the ‘phase-inversion’ method to the measured force time histories for a crest focused wave group and the same wave group inverted. This separation method is found to work well even for locally violent nearly-breaking waves formed from bidirectional wave pairs. It is also found that the
th-harmonic force scales with the
th power of the envelope of both the linear undisturbed free-surface elevation and the linear force component in both time variation and amplitude. This allows estimation of the higher-order harmonic shapes and time histories from knowledge of the linear component alone. The experiments also show that the harmonic structure of the wave loading on the cylinder is virtually unaltered by the introduction of a sloping bed, depending only on the local wave properties at the cylinder. Furthermore, our new experimental results reveal that for certain wave cases the linear loading is actually less than 40 % of the total wave loading and the high-order harmonics contribute more than 60 % of the loading. The significance of this striking new result is that it reveals the importance of high-order nonlinear wave loading on offshore structures and means that such loading should be considered in their design.
With the rapid development of telescopes, both temporal cadence and the spatial resolution of observations are increasing. This in turn generates vast amount of data, which can be efficiently searched only with automated detections in order to derive the features of interest in the observations. A number of automated detection methods and algorithms have been developed for solar activities, based on the image processing and machine learning techniques. In this paper, after briefly reviewing some automated detection methods, we describe our efficient and versatile automated detection method for solar filaments. It is able not only to recognize filaments, determine the features such as the position, area, spine, and other relevant parameters, but also to trace the daily evolution of the filaments. It is applied to process the full disk Hα data observed in nearly three solar cycles, and some statistic results are presented.
Although social harmony is one of the most important cultural values in many of Asian societies it has rarely been studied in the mainstream management literatures. Based on the group-value theory of justice we examined how group justice climates influence group effectiveness through group harmony. Analyses of data on 106 upper-level management teams from Chinese organizations showed that justice climates were positively associated with group harmony, which in turn was positively associated with team task performance and team helping behavior. Group harmony was found to significantly mediate the positive effect of both distributive and interactional justice climates on team helping behavior but only marginally on team task performance. Finally, in support of past research both at the group and individual level, procedural justice climate had the weakest effect on group processes and outcomes. By applying the group value theory on group harmony this paper aims to integrate Eastern and Western perspectives on one hand and the justice climates and group harmony research on the other. Theoretical and practical implications are discussed.
Honeybee foraging can transfer exogenous genes from genetically modified (GM) oilseed rape (Brassica napus L.) to closely related plants, which not only induces potential ecological risks but also contaminates non-GM seeds or honey products with GM ingredients. These events may lead to international trade disputes. Chinese honeybees (Apis cerana cerana Fabricius) and a herbicide (glufosinate)-resistant GM strain of B. napus (Z7B10) were studied to examine the effects of honeybee short-range foraging on oilseed rape gene flow and honey ingredients. Results showed variable frequencies of gene flow between GM and non-GM oilseed rape cultivars, with the highest frequency under nylon net isolation with artificially stocked honeybees, the lowest frequency under nylon net isolation alone, and an intermediate frequency under natural pollination, suggesting the important role of honeybee foraging in gene flow frequency. Additionally, GM pollen grains were found in honey collected from honeybees foraging on both GM and non-GM oilseed rape cultivars. The phosphinothricin acetyltransferase protein was also detected in both unbroken pollen-containing and pollen-free honey by protein testing strips, suggesting that honeybee foraging on GM oilseed rape could lead to contamination with GM ingredients. Overall, the results provide a direct scientific basis for the ecological risk assessment and safety management of GM oilseed rape.
TAOS II is a next-generation occultation survey with the goal of measuring the size distribution of the small end of the Kuiper Belt (objects with diameters 0.5–30 km). Such objects have magnitudes r > 30, and are thus undetectable by direct imaging. The project will operate three telescopes at San Pedro Mártir Observatory in Baja California, México. Each telescope will be equipped with a custom-built camera comprised of a focal-plane array of CMOS imagers. The cameras will be capable of reading out image data from 10,000 stars at a cadence of 20 Hz. The telescopes will monitor the same set of stars simultaneously to search for coincident occultation detections, thus minimising the false-positive rate. This talk described the project, and reported on the progress of the development of the survey infrastructure.
This study investigated the flow bifurcations of flows driven by a pressure gradient in a rectangular curved tube. When fluid flows within a curved tube, due to the centrifugal effect, secondary vortices can be induced in the cross section of the tube. The secondary flow states are dependent on the magnitude of the pressure gradient (q) and the aspect ratio (γ). In this study, the continuation method was applied to investigate the flow bifurcations in a curved tube with increasing pressure gradient (1 < q < 6000) and aspect ratio (0.9 < γ < 1.4).
The bifurcation diagrams are composed of solution branches, which are linked by limiting points or bifurcation points. The flow states in a solution branch belong to the same group. The ranges of the flow states and the relationship between the states can also be derived from the bifurcation diagrams. In this study, two types of bifurcation were found, one in the range of 0.9 < γ < 1.17, and another in the range of 1.18 < γ < 1.4. The ranges of stable flow solutions and the distributions of limit and bifurcation points in both pressure gradient and aspect ratio are derived in this study.
Neoseiulus barkeri (HUGHES) is the natural enemy of spider mites, whiteflies and thrips. Screening for chemically-resistant predatory mites is a practical way to balance the contradiction between the pesticide using and biological control. In this study, the number of eggs laid by fenpropathrin-susceptible and resistant strains of N. barkeri was compared. Additionally, we cloned three N. barkeri vitellogenin (Vg) genes and used quantitative real-time polymerase chain reaction to quantify Vg expression in susceptible and resistant strains. The total number of eggs significantly increased in the fenpropathrin-resistant strain. The full-length cDNA cloning of three N. barkeri Vg genes (NbVg1, NbVg2 and NbVg3) revealed that the open reading frames of NbVg1, NbVg2 and NbVg3 were 5571, 5532 and 4728 bp, encoding 1856, 1843 and 1575 amino acids, respectively. The three N. barkeri Vg possessed the Vitellogenin-N domain (or lipoprotein N-terminal domain (LPD_N)), von Willebrand factor type D domain (VWD) and the domain with unknown function 1943 (DUF1943). The NbVg1 and NbVg2 expression levels were significantly higher in the resistant strain than in the susceptible strain, while the NbVg3 expression level was lower in the resistant strain. Thus, we speculate that the increased number of eggs laid by the fenpropathrin-resistant strain of N. barkeri may be a consequence of changes in Vg gene expression.