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Using data from the China Health and Retirement Longitudinal Study, this research investigates how post-retirement employment influences older people’s expenditure in urban China. By broadening the understanding of post-retirement employment behaviour from a consumer welfare perspective, this study expands the literature on retirement consumption and provides theoretical explanations, empirical insights and policy recommendations. The findings reveal that post-retirement employment behaviour reduces urban retirees’ household expenditure and has a more significant effect on men than on women, but this effect diminishes as consumption levels rise. Increasing income, promoting social participation and improving subjective health outcomes are all potential channels through which post-retirement employment can affect consumption. Further analysis shows two main reasons why post-retirement employment reduces older people’s expenditure: first, the increase in subjective health levels resulting from post-retirement employment reduces healthcare expenditure; second, post-retirement employment does not promote social participation and self-rated health for all consumption levels and all genders of retirees – it also decreases expenditure. Preliminary evidence suggests that internet use positively moderates the negative impact of post-retirement employment on older people’s expenditure. These findings provide policy implications for retirement policies and the promotion of the silver economy.
One species-general life history (LH) principle posits that challenging childhood environments are coupled with a fast or faster LH strategy and associated behaviors, while secure and stable childhood environments foster behaviors conducive to a slow or slower LH strategy. This coupling between environments and LH strategies is based on the assumption that individuals’ internal traits and states are independent of their external surroundings. In reality, individuals respond to external environmental conditions in alignment with their intrinsic vitality, encompassing both physical and mental states. The present study investigated attachment as an internal mental state, examining its role in mediating and moderating the association between external environmental adversity and fast LH strategies. A sample of 1169 adolescents (51% girls) from 9 countries was tracked over 10 years, starting from age 8. The results confirm both mediation and moderation and, for moderation, secure attachment nullified and insecure attachment maintained the environment-LH coupling. These findings suggest that attachment could act as an internal regulator, disrupting the contingent coupling between environmental adversity and a faster pace of life, consequently decelerating human LH.
The objective of this paper is to understand the effects of waves and vaporous cavitation upon the hydrodynamic and hydroelastic responses of a flexible surface-piercing hydrofoil, adding to the subcavitating results presented in Part 1. In general, the presence of a sufficiently large vaporous cavitation bubble facilitated the formation of a ventilated cavity, substantially reducing the angle of attack or speed required to induce fully ventilated flow, relative to subcavitating conditions. A new co-analysis procedure was used to isolate synchronous hydrodynamic modes and structural operating deflection shapes. Significant dynamic load amplification occurred when the resonant frequencies of the first twisting and second bending modes coalesced in both fully wetted and partially cavitating flows. The presence of waves did not diminish the effect of frequency coalescence, but did encourage intermittent lock-in with both leading edge cavity shedding and trailing edge vortex shedding at certain speeds. Partial cavity shedding typically had a negligible impact on the power spectral densities of structural motions because of incoherent cavity shedding. However, lock-in between the cavity shedding frequency and modal coalescence frequency led to shifting of the primary frequency peak, as well as amplified harmonics and interactions between the cavity shedding frequency and vortex shedding frequency. The transition from partially cavitating to fully ventilated flow caused sudden and large drops in the mean hydrodynamic loads and deformations, as well as substantial reductions in the intensity of the fluctuations.
This work describes the effects of waves on the hydroelastic response of a hydrofoil in fully wetted and ventilated flows. In the absence of vaporous cavitation (described in Part 2 of this paper series), shallow long-period non-breaking waves delayed ventilation inception because velocity fluctuations prevent the formation of a stably separated region of flow at the foil's leading edge. Aerated von Kármán vortex shedding occurred from the blunt trailing edge, producing vortex-induced vibration of the hydrofoil at a near-constant Strouhal number. Regular waves led to near sinusoidal oscillations of the load and deformations at the wave encounter frequency, while the mean response and the dynamic response at other frequency peaks corresponding to hydrodynamic and structural modes remained mostly unaffected. Significant dynamic load amplification was observed at a submerged aspect ratio of 2 for cases with low angles of attack because of coalescence between the second and third wetted structural modes; at high angles of attack, the amplitude of the load fluctuations and flow-induced vibrations reduced because energy was diverted away from the coalescence frequencies to the nearby vortex shedding frequency. In both calm water and wave conditions, transition from fully wetted to fully ventilated flow resulted in sudden and significant reduction in the load coefficients, as well as foil deflections. An impulse-like signature was observed in the time-frequency spectra during these transitions. In many of the cases, transition to fully ventilated flow also led to substantially reduced amplitudes in the load and deformation fluctuations.
Metamorphic robots are a new type of unmanned vehicle that can reconfigure and morph between a car mode and a biped walking machine mode. Such a vehicle is superior in trafficability because it can drive at high speeds on its wheels on structured pavement and walk on its legs on unstructured pavement. An engineering prototype of a metamorphic robot was proposed and designed based on the characteristics of wheeled–legged hybrid motion, and reconfiguration planning of the robot was conducted. A kinematics model of the reconfiguration process was established using the screw theory for metamorphic robots. To avoid component impact during the rapid global reconfiguration and achieve smoothness of the reconfiguration process, a rotation rule for each rotating joint was designed and the kinematics model was used to simulate and validate the motion of the system’s end mechanism (front frame) and the entire robot system. Based on the kinematics model and the rotation rules of the rotating joints, a zero-moment point (ZMP) calculation model of the entire robot mechanism in the reconfiguration process was established, and the stability of the reconfiguration motions was evaluated based on the ZMP motion trajectory. The foot landing position was optimized to improve the robot’s stability during the reconfiguration. Finally, the smoothness and stability of the reconfiguration motion were further validated by testing the prototype of the metamorphic robot.
Background: 5-aminolevulinic acid (5-ALA) enhances intraoperative high grade glioma (HGG) tissue visualization. Despite promising randomized clinical trial data suggesting survival benefit for 5-ALA-guided HGG surgery, patient outcome efficacy is not universally accepted. Methods: We performed a systematic review of the literature to evaluate whether there is a beneficial effect upon survival and extent of resection from the utilization of 5-ALA in HGG surgery. Literature regarding 5-ALA usage in HGG surgery was reviewed according to PRISMA guidelines. Results: 3,756 published studies were screened, 536 evaluated, and 45 included. Of studies that directly compared the use of 5-ALA to white light (28.9%), 5-ALA lead to a better progression-free survival (PFS) and overall survival (OS) in 88.4 and 67.5% of patients, respectively. 42.2% demonstrated that 5-ALA use was associated with less post-op neurological deficits, whereas 23.3% of studies showed that surgeries using 5-ALA lead to more deficits. 34.5% demonstrated no difference between 5-ALA and without. Conclusions: 5-ALA was found to be associated with a greater extent of resection and longer OS and PFS in HGG surgeries. Postop neurologic deficit rates were inconclusive when comparing 5-ALA groups to white light groups. 5-ALA is a useful surgical adjunct for HGG resection with preserved patient safety.
This first Australasian edition of the popular text Management across Cultures explores the latest approaches to cross-cultural management, presenting strategies and tactics for managing international assignments and global teams. With a clear emphasis on learning and development, the text encourages students to acquire skills in multicultural competence that will be highly valued by their future employers. As more and more managers find themselves becoming global managers, and in a world where practices and expectations can differ significantly across national and regional boundaries, this has never been more important. Rich in cases and examples, Management across Cultures integrates research from across the social sciences with contemporary management practices for a comprehensive overview of cross-cultural management.
OBJECTIVES/SPECIFIC AIMS: Psoriasis is one of the most common inflammatory diseases of the skin, affecting about 2%–3% of the US population. Despite its high prevalence, its pathogenesis remains poorly understood. The ability of the microbiome to modify host immunity and metabolism suggests that it may contribute to the development of psoriasis and its cardiometabolic comorbidities. This study aims to characterize the psoriatic skin microbiome and understand the functional role that these bacteria may play. METHODS/STUDY POPULATION: 16s rRNA sequencing of site-matched skin swabs from 8 psoriasis patients and 8 healthy controls was used to identify bacteria and determine their relative abundance and microbial community diversity in the sample. PICRUSt was used to infer the functional roles of the bacteria from 16s rRNA amplicon data. RESULTS/ANTICIPATED RESULTS: Lesional psoriasis skin had lower α diversity (p=0.04), less Actinobacteria (p=0.0001), but higher Firmicutes (p=0.009) compared with controls. At the genus level, lesional skin had more Alloiococcus (p=0.01) and Aerococcus (p=0.01) and demonstrated a trend towards lower Propionibacterium (p=0.08) and higher Gallicola (p=0.09) compared to controls. Interestingly, Alloiococcus (p=0.003) and Gallicola (p=0.04) were also higher in nonlesional skin compared with controls. Furthermore, lesional and nonlesional skin shared an increased abundance of Acinetobacter sp., Staphylococcus pettenkoferi, and Streptococcus sp., relative to controls. Lesional and nonlesional psoriasis skin did not differ significantly in microbiome composition. Predictive functional analysis revealed that both the healthy and psoriatic skin microbiome were enriched with bacteria capable of amino acid and carbohydrate metabolism suggest these functions might have a general role in host-microbe interaction. DISCUSSION/SIGNIFICANCE OF IMPACT: These data reveal intriguing differences in the cutaneous microbiome of psoriatic individuals and healthy controls and suggest that bacterial metabolism may play an important role in host-microbe interaction.
The present paper presents a novel method to cope with the difficulty that an N-order filter can introduce a maximum number of transmission zeros (TZs) – no more than N. The method is described by a coupling topology and realized by a regular fully canonical filter structure to increase one more TZ for an N-order filter without any filter size increase. Besides, the TZ shift property, as another advantage of the proposed topology, is investigated. The coupling topology consists of a group of fully canonical coupling nodes with the harmonic node (non-resonating node (NRN)) excited by a λ/4 resonator. Owing to the unique coupling topology and coupling node distribution as well as the inclusion of an NRN, N + 1 TZs are generated by an N-order bandpass filter, while all the TZs are close to the passband and far away from the harmonic passband resulting the highly selective passbands. For demonstration, two-, three-, and four-order filters are designed and measured with the experimental results that confirm the proposed technique.
Thermal-mechanical design is a time-consuming process even at its preliminary design stage. This is due to the large number of components and boundary condition data, the complexity of the geometry, and the iterative nature of the design process. The conventional design process separates the geometric and physical models and results in considerable human interventions during the design process. By assigning the breakpoints to engine assembly features as internal parameters, this article reports a novel feature-based design approach where the associated boundary conditions are represented parametrically along the feature geometric contours. They are updated automatically as per the geometrical changes, including topological changes, and hence bridging the gap between the geometric and physical models. The current approach enables data re-use of both the geometries and physical information from previous engine designs to generate new designs, dispensing with the excessive human interventions. Although the methodology is generic and applicable to other design scenarios, its capability is demonstrated in this article by some representative challenging industrial applications, sitting in the 2D preliminary gas-turbine design domain. The test cases show that the method can significantly reduce the time-cost of the iterative thermal-mechanical design flow.
Let $X$ be a compact Kähler manifold and $\{\unicode[STIX]{x1D703}\}$ be a big cohomology class. We prove several results about the singularity type of full mass currents, answering a number of open questions in the field. First, we show that the Lelong numbers and multiplier ideal sheaves of $\unicode[STIX]{x1D703}$-plurisubharmonic functions with full mass are the same as those of a current with minimal singularities. Second, given another big and nef class $\{\unicode[STIX]{x1D702}\}$, we show the inclusion ${\mathcal{E}}(X,\unicode[STIX]{x1D702})\cap \operatorname{PSH}(X,\unicode[STIX]{x1D703})\subset {\mathcal{E}}(X,\unicode[STIX]{x1D703})$. Third, we characterize big classes whose full mass currents are ‘additive’. Our techniques make use of a characterization of full mass currents in terms of the envelope of their singularity type. As an essential ingredient we also develop the theory of weak geodesics in big cohomology classes. Numerous applications of our results to complex geometry are also given.
In this paper, a compact dual-band bandpass filter (DB-BPF) using new dual-mode resonator-loaded resonators (DM-RLRs) is presented and investigated to simultaneously achieve controllable return loss (RL), bandwidth (BW) and transmission zeros (TZs), and the simple strategy for this type of filter design is proposed. The DB-BPF consists of two high-flexibility DM-RLRs with separated electric and magnetic coupling (SEMC). Specifically, the proposed DM-RLR provides the DB-BPF with center frequency control as well as RL control, and SEMC is utilized for the BW and TZ control. To facilitate the design, a simple optimization-based design strategy is proposed and employed, resulting in an example layout. Finally, the example filter, with center frequencies of 1.57 GHz (channel 1 for GPS) and 3.5 GHz (channel 2 for WiMAX), is fabricated and measured. The measurement insertion loss and RL are 0.9/0.9 and 17/20 dB. The fabricated DB-BPF also exhibits a compact size of 0.12λg × 0.08λg at 1.57 GHz.
In this paper, a double-passage shape correction (DPSC) method is presented for simulation of unsteady flows around vibrating blades and aeroelastic prediction. Based on the idea of phase-lagged boundary conditions, the shape correction method was proposed aimed at efficiently dealing with unsteady flow problems in turbomachinery. However, the original single-passage shape correction (SPSC) may show the disadvantage of slow convergence of unsteady solutions and even produce nonphysical oscillation. The reason is found to be related with the disturbances on the circumferential boundaries that can not be damped by numerical schemes. To overcome these difficulties, the DPSC method is adopted here, in which the Fourier coefficients are computed from flow variables at implicit boundaries instead of circumferential boundaries in the SPSC method. This treatment actually reduces the interaction between the calculation of Fourier coefficients and the update of flow variables. Therefore a faster convergence speed could be achieved and also the solution stability is improved. The present method is developed to be suitable for viscous and turbulent flows. And for real three-dimensional (3D) problems, the rotating effects are also considered. For validation, a 2D oscillating turbine cascade, a 3D oscillating flat plate cascade and a 3D practical transonic fan rotor are investigated. Comparisons with experimental data or other solutions and relevant discussions are presented in detail. Numerical results show that the solution accuracy of DPSC method is favorable and at least comparable to the SPSC method. However, fewer iteration cycles are needed to get a converged and stable unsteady solution, which greatly improves the computational efficiency.
In this letter, a passive high-selectivity dual-band filter with two controllable transmission zero (TZ) pairs is proposed, while synthesis method and control mechanism of the two TZ pairs are investigated. Specifically, by employing the magnetic/electric mixed coupling (MEMC), source–load coupling (S–L coupling) and stepped-impedance resonators, a dual-band bandpass filter with two pairs of controllable TZs is constructed. Two controllable TZ pairs can be independently adjusted by re-modifying the associated coupling structures. To validate the synthesizability and controllability of the TZ pairs, mathematical synthesis, and EM simulations are carried out. Two demonstrative filters with identical passband performance and different central TZ distributions for GSM (0.9/1.8 GHz) are designed and measured. The analysis and experimental results show that the synthesis-controllable TZ pair (fz2, fz3) introduced by MEMC can be synthesized and controlled using inline mixed coupling synthesis, and the optimization-controllable TZ pair (fz1, fz4) because of S–L coupling is controlled by S–L coupling strength optimization procedure.