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Background The relevance of iron status biomarkers for coronary artery disease (CAD), heart failure (HF), ischemic stroke (IS), and type 2 diabetes (T2D) is uncertain. We compared the observational and Mendelian randomization (MR) analyses of iron status biomarkers and hemoglobin with these diseases. Methods and Results Observational analyses of hemoglobin were compared with genetically predicted hemoglobin with cardiovascular diseases and diabetes in the UK Biobank. Iron biomarkers included transferrin saturation, serum iron, ferritin, and total iron binding capacity. MR analyses assessed associations with CAD (CARDIOGRAMplusC4D [Coronary Artery Disease Genome Wide Replication and Meta‐Analysis Plus The Coronary Artery Disease Genetics], n=181 522 cases), HF (HERMES [Heart Failure Molecular Epidemiology for Therapeutic Targets), n=115 150 cases), IS (GIGASTROKE, n=62 100 cases), and T2D (DIAMANTE [Diabetes Meta‐Analysis of Trans‐Ethnic Association Studies], n=80 154 cases) genome‐wide consortia. Observational analyses demonstrated J‐shaped associations of hemoglobin with CAD, HF, IS, and T2D. In contrast, MR analyses demonstrated linear positive associations of higher genetically predicted hemoglobin levels with 8% higher risk per 1 SD higher hemoglobin for CAD, 10% to 13% for diabetes, but not with IS or HF in UK Biobank. Bidirectional MR analyses confirmed the causal relevance of iron biomarkers for hemoglobin. Further MR analyses in global consortia demonstrated modest protective effects of iron biomarkers for CAD (7%–14% lower risk for 1 SD higher levels of iron biomarkers), adverse effects for T2D, but no associations with IS or HF. Conclusions Higher levels of iron biomarkers were protective for CAD, had adverse effects on T2D, but had no effects on IS or HF. Randomized trials are now required to assess effects of iron supplements on risk of CAD in high‐risk older people.

Onion waste, particularly onion skin, is a widely generated waste material, and harnessing its potential for energy storage aligns with sustainable development goals. Despite the high specific surface area exhibited by biocarbon derived from onion skin, its Li-ion storage performance is not desirable. In this study, biocarbon derived from purple onion skin serves as the substrate for accommodating cobalt oxide (Co3O4) through a hydrothermal method, employing Co(NO3)2·6H2O at various concentrations, and with and without prior activation using KOH treatment. The resulting samples undergo comprehensive analyses, including phase, morphological, surface, and electrochemical characterizations. The Co3O4 decoration on activated carbon derived from onion skin, synthesized using Co(NO3)2·6H2O at a concentration of 1 M, reveals a porous structure with a surface area of 702 m2/g, featuring predominant pore sizes of less than 5 nm. Significantly, the Li-ion storage performance of this sample surpasses that of alternative samples, demonstrating a remarkable reversible capacity of 451 mAh/g even after 500 cycles at an elevated current density of 2000 mAh/g. The charge transfer resistance of the sample (110.3 Ω) is found to be substantially lower than that of the sample prepared using carbonized onion skin biomass without activation. This research introduces an innovative approach leveraging onion skin waste as a template for Co3O4 decoration, thereby fabricating high-performance anodes for lithium-ion batteries.

The nighttime economy (NTE) is one of the primary measures used by the Chinese government to promote urban consumption and capital flow. Especially after COVID-19, more regulations were introduced by both the central and local governments to accelerate this commercial activity. However, the relationship between the NTE and urban development is controversial. There has been controversy over the relationship between the nighttime economy and urban development. We believe that organizations/individuals embedded in different regional contexts have different behavioral patterns, which, in turn, can make cities develop nighttime commercial activities differently. We wonder whether the nighttime economy’s large-scale development fits the diverse regional development. There is a lack of discussions of the spatial distribution of nighttime commercial activities from an urban geographical perspective, especially the differences and mechanisms of urban systems based on the nighttime economy. Based on existing research arguments, this article collects points of interest (POI) and nighttime light (NTL) remote sensing data (RSD) to spatialize nighttime economic activities in order to provide a reference for reasonable regional and urban economic planning. The nighttime economy (NTE) is one of the primary channels used by the Chinese government to promote urban consumption and capital flow, and the relationship between the NTE and urban development is controversial. Based on existing research, we selected the Yangtze River Delta (YRD) region as an example. We found that there are core–peripheral spatial patterns in nighttime commercial urban systems. The core is Shanghai, and provincial-level core cities form the second category, largely overlapping with the administrative urban system. Although the NTE is primarily concentrated in economically developed coastal areas, it spreads in the northwest–southeast direction, indicating that opportunities will arise in the geo-periphery. Although regulations encourage the growth of the NTE, infrastructure cannot fully support large-scale centralized expansion. The interaction of critical factors, such as urban policies, residents’ consumption, industrial structure, and economic foundations, may affect nighttime activities.

Bone drilling is a routine operation in surgeries, such as neurosurgery and orthopedics. However, the excessive drilling temperature may cause severe thermal damage to the bone tissue. Therefore, the drilling temperature determination of bone tissue can reduce the harm caused by thermal damage. A time-varying temperature field simulation model of bone drilling was set up by ABAQUS software in this paper, based on the Johnson-Cook model. Then it was validated with experiments by drilling cortical bone of fresh bovine shaft of the femur. The relative error between the experimental values and the theoretical values within 7.67% showed a good consistency. Furthermore, the aging factor is also considered to evaluate the temperature field of bone drilling. The results showed that the drilling temperature near the bone-drill area increased significantly. The drilling temperature of cortical bone decreases sharply with the radial distance and exhibits a hysteresis lag in the axial distribution. The aging factor mainly affects the peak of drilling temperature. The peak of drilling temperature tends to increase with age. The peak drilling temperature in the elderly (70y) was up to 6.8% higher than that in the young (20y), indicating that the elderly is more prone to excessive drilling temperature. Therefore, special attention should be paid to the temperature control of elderly bone tissue.

Infrastructure construction related to the new generation of information technology and 5G technology is an important measure taken by the Chinese government to promote regional economic development. Large-scale infrastructure investment is being carried out simultaneously in China's core and peripheral regions. The COVID-19 pandemic has dealt a severe blow to China's tourism industry, and the application of new technologies seems to blur the spatial boundaries of the tourism industry. Therefore, it is debatable whether the zealous development of large investment projects can really improve the competitiveness of the regional tourism industry. This paper discusses this topical issue by empirically analyzing data from 31 Chinese provinces and cities from 2008-2019 and draws the following conclusions (1) The continuous expansion of new infrastructure investment in China indeed has a positive effect on improving China's overall tourism competitiveness. However, the inverted U-shaped relationship between the two shows that China should not blindly expand the scale of infrastructure construction and make appropriate investment according to the regional industrial development level. (2) Although convergent infrastructure plays an important role in regional industrial competitiveness, the marginal effect has begun to weaken, so the problem of scale inefficiency needs to be addressed. In contrast, the input of innovation infrastructure is insufficient to enhance industrial competitiveness and can be moderately increased to achieve better results. (3) China's core economic areas have a good driving effect on new infrastructure investment, but the original technological innovation and transformation-type facilities are still the key to limiting the improvement of industrial competitiveness. Peripheral areas are more passive recipients with strong demand. Therefore, investment in various types of infrastructure can drive regional development.

A conventional dynamic vibration absorber based on resonance effect can hardly satisfy the requirement for low-frequency and broadband vibration control in actual engineering. Combined with passive and nonlinear vibration absorption strategy, this study employed nonlinear characteristics of the magnetic force, bistable structure to establish the dynamic model of the main system with a bistable vibration absorber. The nonlinear motion states of the structure under different excitation conditions were analyzed to explore the inherent relation between the chaotic and large amplitude motion and the vibration absorber’s operating performance. The effect laws of the structural parameters on the dynamic characteristics of the nonlinear vibration absorber and the main system were developed to obtain the optimal parameter settings in the case of resonance and off-resonance of the main system. These results provide an insightful theoretical foundation for the optimal design of the nonlinear vibration absorber.

Thin-walled workpieces of silicon carbide particle-reinforced aluminum matrix (SiC p /Al) composites with outstanding properties have been widely applied in many fields, such as automobile, weapons, and aerospace. However, the thin-walled workpieces exhibit poor rigidity, large yield ratio, and easily deform under the cutting force and cutting heat during the machining process. Herein, in order to improve the processing efficiency and precision of higher volume fraction SiC p /Al composite thin-walled workpieces, the influence of different high-speed milling parameters and machining paths on the edge defects is analyzed. The results reveal that the cutting force initially increased and then decreased with the cutting speed. Besides, the cutting force steadily increased with radial cutting depth and feed per tooth, but the influence of feed per tooth is less than radial cutting depth. After up-milling cut-in and cut-out processing and down-milling cut-out processing, the cut-in end of the workpiece exhibited higher breakage and obvious edge defects. However, the workpiece edges remained intact after down-milling cut-in processing. In conclusion, a higher cutting speed, a smaller radial cutting depth, and moderate feed per tooth are required to decrease the cutting force during the milling of SiC p /Al composite thin-walled workpiece. Furthermore, down-milling cut-in processing mode can reduce the edge defects and improve the processing efficiency and precision of the workpiece.

The physical meaning of phase difference controls the occurrence time of peak values of triangular series, which can be abbreviated as peak arrival time. This article describes a method for deducing the correspondence between the energy distribution characteristics in the time domain and the peak arrival time. The variation laws of acceleration time–history curve of natural seismic wave can be transformed into its energy distribution characteristics in time domain. Based on the needs of seismic engineering, this article proposes a conversion formula to describe the relationship between the peak arrival time and the energy distribution characteristics in the time domain. To ensure that the variation laws of acceleration time–history curve of artificial seismic waves are more consistent with those of natural seismic waves, a normal-fitting annealing algorithm is proposed based on the normal-fitting method. The proposed method not only considers the frequency distribution characteristics of the peak arrival time comprehensively but also optimizes the fitting parameters according to the actual situation. The results of all the experimental cases verify the rationality and reliability of the proposed method.

To understand the performance of a queueing system, it can be useful to focus on the evolution of the content that is initially in service at some time. That necessarily will be the case in service systems that provide service during normal working hours each day, with the system shutting down at some time, except that all customers already in service at the termination time are allowed to complete their service. Also, for infinite-server queues, it is often fruitful to partition the content into the initial content and the new input, because these can be analyzed separately. With i.i.d service times having a non-exponential distribution, the state of the initial content can be described by specifying the elapsed service times of the remaining initial customers. That initial content process is then a Markov process. This paper establishes a many-server heavy-traffic (MSHT) functional central limit theorem (FCLT) for the initial content process in the space DD, assuming a FCLT for the initial age process, with the number of customers initially in service growing in the limit. The proof applies a symmetrization lemma from the literature on empirical processes to address a technical challenge: For each time, including time 0, the conditional remaining service times, given the ages, are mutually independent but in general not identically distributed.

Under general conditions, the number of customers in a GI/D/s+GI many-server queue at time t converges to a unique stationary distribution as t → ∞. However, simulations show that the sample paths routinely exhibit nearly periodic behavior over long time intervals when the system is overloaded and s is large, provided that the system does not start in steady state. Moreover, the precise periodic behavior observed depends critically on the initial conditions. We provide insight into the transient behavior by studying the deterministic fluid model, which arises as the many-server heavy-traffic limit. The limiting fluid model also has a unique stationary point, but that stationary point is not approached from any other initial state as t → ∞. Instead, the fluid model performance approaches one of its uncountably many periodic steady states, depending on the initial conditions. Simulation experiments confirm that the time-dependent performance of the stochastic queueing model is well approximated by the fluid model. Like the fluid model, the behavior of the queueing system is highly sensitive to the initial conditions over long intervals of time.