THE SUPPLY CHAIN OF PORK: U.S. AND CHINA

Consumers in the United States consume 53 pounds of pork per capita per year. Forty percent of that pork enters the market by way of a contract with a packer or an integrated supply chain arrangement. Chinese consumers consume 37 pounds per capita. Eighty percent of that pork is produced in the backyards of millions of households all over the countryside. The supply chain that brings pork from hog to human is clearly different in these two countries, but both are moving in the same direction. In the United States, pork breeding produced leaner but heavier hogs by the late 1990's. This was largely in response to consumer demand for leaner meat and processors demand for less waste. Stricter sanitation regulation and quality control by food manufacturers led to a more integrated supply chain. Food companies contract with farmers for hogs with particular characteristics being demanded by consumers and retailers. Half of fresh pork and forty percent of processed pork is sold through foodservice establishments in the U.S. Consumers need for time-saving food is revealed by the portion of pork they eat away from home (42% of $35 billion sales) and by the mix of fresh (27%) and processed (73%) pork purchased in retail stores. The emphasis in the U.S. supply chain for pork is on delivering consistent quality of safe meat to consumers all the time. There is considerable research into new pork products. The top ten processing plants handle 43 percent of the total output. China is the largest pork producer in the world slaughtering 526.7 million hogs in 2000, over five times as many as the United States. Although commercial operations and specialized households are growing they provide only about twenty percent of all China's pork. Lower quality and sanitation standards prevent pork produced in backyards from entering the westernized/commercial supply chain but it is an important source of meat in the inland and rural areas of China. Coastal cities have more commercial and imported pork. For example, in Beijing sixty percent of production is from commercial farms. The advent of retail supermarkets and higher incomes in China foretell an increase in commercial pork operations. Direct foreign investment by key Western food companies and retailers are leading the standards for food safety and handling in the larger cities. Based on current pork consumption at various income levels, it is estimated that pork consumption will grow more than seven percent in Chinese cities and 1.5 percent in the countryside over the next ten years. This translates into an additional 12 million pounds of pork in 2011 with the urban consumption surpassing the rural consumption. The pork industry will be driven to emphasize quality, sanitation, and convenience in China as they already do in the United States. With China entering the World Trade Organization (WTO) more pork imports can be expected. Exports will depend on meeting the quality and safety standards of importing countries.Industrial Organization, Livestock Production/Industries,

The In-Sample Softmax for Offline Reinforcement Learning

Reinforcement learning (RL) agents can leverage batches of previously collected data to extract a reasonable control policy. An emerging issue in this offline RL setting, however, is that the bootstrapping update underlying many of our methods suffers from insufficient action-coverage: standard max operator may select a maximal action that has not been seen in the dataset. Bootstrapping from these inaccurate values can lead to overestimation and even divergence. There are a growing number of methods that attempt to approximate an \emph{in-sample} max, that only uses actions well-covered by the dataset. We highlight a simple fact: it is more straightforward to approximate an in-sample \emph{softmax} using only actions in the dataset. We show that policy iteration based on the in-sample softmax converges, and that for decreasing temperatures it approaches the in-sample max. We derive an In-Sample Actor-Critic (AC), using this in-sample softmax, and show that it is consistently better or comparable to existing offline RL methods, and is also well-suited to fine-tuning

THE SUPPLY CHAIN OF PORK: U.S. AND CHINA

Consumers in the United States consume 53 pounds of pork per capita per year. Forty percent of that pork enters the market by way of a contract with a packer or an integrated supply chain arrangement. Chinese consumers consume 37 pounds per capita. Eighty percent of that pork is produced in the backyards of millions of households all over the countryside. The supply chain that brings pork from hog to human is clearly different in these two countries, but both are moving in the same direction. In the United States, pork breeding produced leaner but heavier hogs by the late 1990's. This was largely in response to consumer demand for leaner meat and processors demand for less waste. Stricter sanitation regulation and quality control by food manufacturers led to a more integrated supply chain. Food companies contract with farmers for hogs with particular characteristics being demanded by consumers and retailers. Half of fresh pork and forty percent of processed pork is sold through foodservice establishments in the U.S. Consumers need for time-saving food is revealed by the portion of pork they eat away from home (42% of $35 billion sales) and by the mix of fresh (27%) and processed (73%) pork purchased in retail stores. The emphasis in the U.S. supply chain for pork is on delivering consistent quality of safe meat to consumers all the time. There is considerable research into new pork products. The top ten processing plants handle 43 percent of the total output. China is the largest pork producer in the world slaughtering 526.7 million hogs in 2000, over five times as many as the United States. Although commercial operations and specialized households are growing they provide only about twenty percent of all China's pork. Lower quality and sanitation standards prevent pork produced in backyards from entering the westernized/commercial supply chain but it is an important source of meat in the inland and rural areas of China. Coastal cities have more commercial and imported pork. For example, in Beijing sixty percent of production is from commercial farms. The advent of retail supermarkets and higher incomes in China foretell an increase in commercial pork operations. Direct foreign investment by key Western food companies and retailers are leading the standards for food safety and handling in the larger cities. Based on current pork consumption at various income levels, it is estimated that pork consumption will grow more than seven percent in Chinese cities and 1.5 percent in the countryside over the next ten years. This translates into an additional 12 million pounds of pork in 2011 with the urban consumption surpassing the rural consumption. The pork industry will be driven to emphasize quality, sanitation, and convenience in China as they already do in the United States. With China entering the World Trade Organization (WTO) more pork imports can be expected. Exports will depend on meeting the quality and safety standards of importing countries

Quantitative evaluation of fracture development in Triassic Yanchang Formation, Ordos Basin, NW China

To uniformly evaluate the fracture development of the Triassic Yanchang Formation in Ordos Basin, a set of evaluation methods for fracture development degree is established by observation and account of fractures developed in the sandstone cores of the Yanchang Formation in the five blocks of Maling, Huaqing, Anbian, Wuqi and Yanhewan in the Shaanbei Slope. The methods include four aspects of qualitative and quantitative indices, i.e., fracture type, fracture strength, fracture grade and fracture assemblage, which are applicable to the fracture assorting, single well evaluation, block evaluation and belt evaluation, respectively. Quantitative evaluation plates of block fracture development degree have been built and applied to evaluate the fracture development degree of the five blocks. The Chang 71 Member in Maling block has high angle fractures of three grades (weak, moderate and strong) developed simultaneously and low angle fractures in moderate-strong development degree; the Chang 72 Member in Maling block has weakly to moderately developed high angle fractures and moderately to strongly developed low angle fractures; both the Chang 71 and Chang 72 members in Anbian block have strongly developed high angle fractures, but undeveloped low angle fractures; the Chang 63 Member in Huaqing block has undeveloped high angle fractures and moderately to strongly developed low angle fractures locally; the Chang 6 members in Wuqi block and Yanhewan block have undeveloped high angle fractures and low angle fractures. Key words: Ordos Basin, Triassic Yanchang Formation, fracture development, quantitative fracture evaluatio

Conditionally Optimistic Exploration for Cooperative Deep Multi-Agent Reinforcement Learning

Efficient exploration is critical in cooperative deep Multi-Agent Reinforcement Learning (MARL). In this work, we propose an exploration method that effectively encourages cooperative exploration based on the idea of sequential action-computation scheme. The high-level intuition is that to perform optimism-based exploration, agents would explore cooperative strategies if each agent's optimism estimate captures a structured dependency relationship with other agents. Assuming agents compute actions following a sequential order at \textit{each environment timestep}, we provide a perspective to view MARL as tree search iterations by considering agents as nodes at different depths of the search tree. Inspired by the theoretically justified tree search algorithm UCT (Upper Confidence bounds applied to Trees), we develop a method called Conditionally Optimistic Exploration (COE). COE augments each agent's state-action value estimate with an action-conditioned optimistic bonus derived from the visitation count of the global state and joint actions of preceding agents. COE is performed during training and disabled at deployment, making it compatible with any value decomposition method for centralized training with decentralized execution. Experiments across various cooperative MARL benchmarks show that COE outperforms current state-of-the-art exploration methods on hard-exploration tasks.Comment: Accepted at UAI 202

Exposure to polystyrene nanoplastics induces abnormal activation of innate immunity via the cGAS-STING pathway

Endogenous immune defenses provide an intrinsic barrier against external entity invasion. Microplastics in the environment, especially those at the nanoscale (nanoplastics or NPs), may pose latent health risks through direct exposure. While links between nanoplastics and inflammatory processes have been established, detailed insights into how they may perturb the innate immune mechanisms remain uncharted. Employing murine and macrophage (RAW264.7) cellular models subjected to polystyrene nanoplastics (PS-NPs), our investigative approach encompassed an array of techniques: Cell Counting Kit-8 assays, flow cytometric analysis, acridine orange/ethidium bromide (AO/EB) fluorescence staining, cell transfection, cell cycle scrutiny, genetic manipulation, messenger RNA expression profiling via quantitative real-time PCR, and protein expression evaluation through western blotting. The results showed that PS-NPs caused RAW264.7 cell apoptosis, leading to cell cycle arrest, and activated the cGAS-STING pathway. This resulted in NF-κB signaling activation and increased pro-inflammatory mediator expression. Importantly, PS-NPs-induced activation of NF-κB and its downstream inflammatory cascade were markedly diminished after the silencing of the STING gene. Our findings highlight the critical role of the cGAS-STING pathway in the immunotoxic effects induced by PS-NPs. We outline a new mechanism whereby nanoplastics may trigger dysregulated innate immune and inflammatory responses via the cGAS/STING pathway