24 research outputs found

    Evaluation of individual and ensemble probabilistic forecasts of COVID-19 mortality in the United States

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    Short-term probabilistic forecasts of the trajectory of the COVID-19 pandemic in the United States have served as a visible and important communication channel between the scientific modeling community and both the general public and decision-makers. Forecasting models provide specific, quantitative, and evaluable predictions that inform short-term decisions such as healthcare staffing needs, school closures, and allocation of medical supplies. Starting in April 2020, the US COVID-19 Forecast Hub (https://covid19forecasthub.org/) collected, disseminated, and synthesized tens of millions of specific predictions from more than 90 different academic, industry, and independent research groups. A multimodel ensemble forecast that combined predictions from dozens of groups every week provided the most consistently accurate probabilistic forecasts of incident deaths due to COVID-19 at the state and national level from April 2020 through October 2021. The performance of 27 individual models that submitted complete forecasts of COVID-19 deaths consistently throughout this year showed high variability in forecast skill across time, geospatial units, and forecast horizons. Two-thirds of the models evaluated showed better accuracy than a naïve baseline model. Forecast accuracy degraded as models made predictions further into the future, with probabilistic error at a 20-wk horizon three to five times larger than when predicting at a 1-wk horizon. This project underscores the role that collaboration and active coordination between governmental public-health agencies, academic modeling teams, and industry partners can play in developing modern modeling capabilities to support local, state, and federal response to outbreaks

    The production process of "Book of Reminiscence", a 3rd person historical role-playing game

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    This report presents an exhaustive account of the production process for a historically-themed role-playing game "Book of Reminiscence" in the Song Dynasty. The game revolves around the journey of a scholar named Song Shu, who unexpectedly becomes the owner of his family's longstanding bookstore following the untimely demise of his parents. Additionally, the narrative incorporates a mystical engraved stone as a critical element. The game is designed as a third-person perspective PC game developed using Unreal Engine 5. It features a unique hybrid approach, combining 2D pixel-style characters with a 3D voxel-style environment. Players will engage in puzzle-solving activities within the intricately designed two-story bookstore setting.Bachelor of Fine Arts in Digital Animatio

    Hybrid Precoding With Rate and Coverage Constraints for Wideband Massive MIMO Systems

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    Preparation and Performance Test of the Super-Hydrophobic Polyurethane Coating Based on Waste Cooking Oil

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    In order to solve the problem of dust accumulation on the fin surface of a mine air cooler, a method of preparing super-hydrophobic polyurethane (SPU) coating based on waste cooking oil (WCO) was proposed. Firstly, the polyurethane prepolymer was synthesized with WCO as a raw material, and then the polyurethane prepolymer was modified with amino-terminated polydimethylsiloxane (ATP) to obtain SPU emulsion. The chemical structure and thermal stability of SPU were characterized by infrared spectrum and thermogravimetric analysis. A series of nanocomposites were prepared by combining modified silicon carbide (APT-SiC) particles and SPU emulsions. According to the parameters of pull-off strength, contact angle, sliding angle and thermal conductivity, the filler ratio of nanocomposites was optimized. The test results show that when the content of APT-SiC particles is 20 wt %, super-hydrophobic polyurethane coating can be obtained. The coating has good pull- off strength and thermal conductivity, and the contact angle and sliding angle are 161° and 3°, respectively. In addition, the practical application of the super-hydrophobic polyurethane coating was tested by related experiments. The experimental results show that the coating has good self-cleaning, wear resistance and anti-corrosion performance, can meet the requirements of air coolers in special environments, and has great application prospects

    Velvet Family Protein FpVelB Affects Virulence in Association with Secondary Metabolism in <i>Fusarium pseudograminearum</i>

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    Fusarium pseudograminearum causes destructive crown disease in wheat. The velvet protein family is a crucial regulator in development, virulence, and secondary metabolism of fungi. We conducted a functional analysis of FpVelB using a gene replacement strategy. The deletion of FpVelB decreased radial growth and enhanced conidial production compared to that of wild type. Furthermore, FpVelB modulates the fungal responses to abiotic stress through diverse mechanisms. Significantly, virulence decreased after the deletion of FpVelB in both the stem base and head of wheat. Genome-wide gene expression profiling revealed that the regulation of genes by FpVelB is associated with several processes related to the aforementioned phenotype, including “immune”, “membrane”, and “antioxidant activity”, particularly with regard to secondary metabolites. Most importantly, we demonstrated that FpVelB regulates pathogen virulence by influencing deoxynivalenol production and modulating the expression of the PKS11 gene. In conclusion, FpVelB is crucial for plant growth, asexual development, and abiotic stress response and is essential for full virulence via secondary metabolism in F. pseudograminearum

    A chaos wolf optimization algorithm with self-adaptive variable step-size

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    To explore the problem of parameter optimization for complex nonlinear function, a chaos wolf optimization algorithm (CWOA) with self-adaptive variable step-size was proposed. The algorithm was based on the swarm intelligence of wolf pack, which fully simulated the predation behavior and prey distribution way of wolves. It possessed three intelligent behaviors such as migration, summons and siege. And the competition rule as “winner-take-all” and the update mechanism as “survival of the fittest” were also the characteristics of the algorithm. Moreover, it combined the strategies of self-adaptive variable step-size search and chaos optimization. The CWOA was utilized in parameter optimization of twelve typical and complex nonlinear functions. And the obtained results were compared with many existing algorithms, including the classical genetic algorithm, the particle swarm optimization algorithm and the leader wolf pack search algorithm. The investigation results indicate that CWOA possess preferable optimization ability. There are advantages in optimization accuracy and convergence rate. Furthermore, it demonstrates high robustness and global searching ability

    The Effects of Mycovirus BmPV36 on the Cell Structure and Transcription of <i>Bipolaris maydis</i>

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    Bipolaris maydis partitivirus 36 (BmPV36) is a mycovirus that can significantly reduce the virulence of the host Bipolaris maydis, but its hypovirulence mechanism is not clear. To investigate the response of B. maydis to BmPV36, the effects of BmPV36 on host cell structure and gene expression were studied via transmission electron microscopy and transcriptome sequencing using BmPV36-carrying and virus-free mycelium on the second and fifth culture. The results of transmission electron microscopy showed that the cell wall microfibrils of B. maydis were shortened, the cell membrane was broken, and membrane-bound vesicles and vacuoles appeared in the cells after carrying BmPV36. Transcriptome sequencing results showed that after carrying BmPV36, B. maydis membrane-related genes were significantly up-regulated, but membrane transport-related genes were significantly down-regulated. Genes related to carbohydrate macromolecule polysaccharide metabolic and catabolic processes were significantly down-regulated, as were genes related to the synthesis of toxins and cell wall degrading enzymes. Therefore, we speculated that BmPV36 reduces the virulence of B. maydis by destroying the host’s cell structure, inhibiting the synthesis of toxins and cell wall degrading enzymes, and reducing cell metabolism. Gaining insights into the hypovirulence mechanism of mycoviruses will provide environmentally friendly strategies for the control of fungal diseases

    Relationship between Soil Characteristics and Stand Structure of Robinia pseudoacacia L. and Pinus tabulaeformis Carr. Mixed Plantations in the Caijiachuan Watershed: An Application of Structural Equation Modeling

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    In order to study the multi-factor coupling relationships between typical Robinia pseudoacacia L. and Pinus tabulaeformis Carr. mixed plantations in the Caijiachuan basin of the Loess Plateau of Shanxi Province, West China, 136 sample plots were selected for building a structural equation model (SEM) of three potential variables: terrain, stand structure, and soil characteristics. Additionally, the indicators (also known as observed variables) were studied in this paper, including slope, altitude, diameter at breast height (DBH), tree height (TH), tree crown area, canopy density, stand density, leaf area index (LAI), soil moisture content, soil maximum water holding capacity (WHC), soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), ammonia-nitrogen (NH3-N), nitrate-nitrogen (NO3-N), and available phosphorus (AP). The results showed that terrain was the most important factor influencing soil moisture and nutrients, with a total impact coefficient of 1.303 and a direct path coefficient of 0.03, which represented mainly positive impacts; while correspondingly stand structure had a smaller negative impact on soil characteristics, with a total impact coefficient of −0.585 and a direct path coefficient of −0.01. The terrain also had a positive impact on the stand structure, with a total impact coefficient of 0.487 and a direct path coefficient of 0.63, indicating that the topography factors were more suitable for site conditions and both the stand structure and the soil moisture and nutrient conditions were relatively superior. By affecting the stand structure, terrain could restrict some soil, water, and nutrient functions of soil and water conservation. The influence coefficients of the four observed variables of DBH, stand density, soil water content, and organic matter, and potential variable topography reached 0.686, −0.119, 1.117, and 0.732, respectively; and the influence coefficients of soil moisture, organic matter and stand structure were −0.502 and −0.329, respectively. Therefore, besides observing the corresponding latent variables, the observed variables had a considerable indirect influence on other related latent variables. These relationships showed that the measures, such as changing micro-topography and adjusting stand density, should effectively maintain or enhance soil moisture and nutrient content so as to achieve improved soil and water conservation benefits in the ecologically important Loess Area
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