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In the rapid process of urbanization, crucial habitats for mid-sized felids such as bobcats are increasingly compromised. This study employs Geographic Information System (GIS) tools and Machine Learning to investigate the subtle impacts of urbanization on bobcat habitats. Focused on the San Jose area, our extensive geospatial analysis has developed a complex ecological model for bobcat habitats. Our findings emphasize the significant influence of factors like vegetation cover, water body distribution, road traffic volume, and intersection density on the suitability of habitats for bobcats. Specifically, we discovered that while vegetation cover typically supports habitat suitability, its proximity to busy roads significantly undermines this advantage, indicating a need for strategic urban planning that incorporates wildlife mobility. By synthesizing natural and urban elements, we offer fresh insights into urban ecosystem management and propose specific conservation tactics: identifying optimal wildlife crossings, integrating corridors with urban infrastructure, and placing fencing and signage strategically to facilitate wildlife movement safely. These measures aim to reduce road-related threats and enhance the integrity of natural habitats, strengthening bobcat conservation efforts. More than its direct implications for bobcat conservation, this study offers actionable insights for urban wildlife conservation and introduces innovative methods for assessing and mitigating the broader ecological impacts of urbanization. [ABSTRACT FROM AUTHOR]

In modern cities, urban public spaces, such as parks, gardens, plazas, and streets, play a big role in people's social activities, physical activities, mental health, and overall well-being. However, the traditional post-occupancy evaluation (POE) process for public spaces such as large urban parks is extremely difficult, especially for long-term user experiences through observations, surveys, and interviews. On the other hand, social media has emerged as a major media outlet recording millions of user experiences to the public, which provides opportunities to inform how public space is used and perceived by users. Furthermore, unlike previous research that primarily presented descriptive characters of park programs, our study employs a network model to elucidate the interactive relationships and intensities among reported park elements, human activities, and experiences. This approach enables us to track the sources within the space that impact people's perceptions, such as weather conditions, food options, and notable landmarks. The utilization of this network model opens avenues for future research to comprehensively investigate the factors shaping people's perceptions in public open spaces. This study uses Bryant Park as an example and presents a new analytical framework, POSE (post-occupancy social media evaluation), to support long-term POE studies for large public spaces. Methods such as data automation, descriptive statistics, and social network analysis were used. The identification and quantification of meaningful park activities, scenes, and sentiments as well as their relationships will help optimize the design and management of park programs. [ABSTRACT FROM AUTHOR]

Aiming at the surrounding rock failure of heterogeneous and unequal pressure circular roadways, the approximate analytical algorithm of the plastic zone is proposed. Through the comparison of analytical calculations and numerical simulation, the shape characteristics and evolution law of the surrounding rock's plastic zone are studied, and the relative error of the two calculation methods is analyzed. The results show the following: (1) With an increase or decrease in the lateral pressure coefficient, the shape of the plastic zone of the roadway-surrounding rock presents a circular-ellipse-butterfly shape change law, and the outer edge of the plastic zone presents a scattered shape, without a continuous boundary. (2) In the butterfly-shaped plastic zone, the butterfly leaf always lies between the maximum confining pressure and the minimum confining pressure and rotates with the pressure. (3) There is a certain amount of error between the maximum value of the plastic zone solved by an analytical algorithm and numerical simulation, and the relative error is positively related to the burial depth and lateral pressure coefficient of the roadway and negatively related to the strength of the surrounding rock. (4) In addition, the relative error of the plastic zone calculation of the multi-layer heterogeneous combination roadway is larger than that of the single heterogeneous roadway. [ABSTRACT FROM AUTHOR]

Three anthraquinones--emodin, chrysophanol, and physcion--were successfully purified from the dichloromethane extract of the Chinese medicinal herb Rumex japonicus by high-speed counter-current chromatography (HSCCC). The extract was separated with n-hexane-ethanol-water (18:22:3, v/v/v) as the two-phase solvent system and yielded 3.4 mg of emodin, 24.1 mg of chrysophanol, and 2.0 mg of physcion from 500 mg of sample with purities of 99.2 %, 98.8% and 98.2%, respectively. The HSCCC fractions were analyzed by high-performance liquid chromatography (HPLC) and the chemical structures of the three anthraquinones were confirmed by ¹H-NMR and ¹³C-NMR analysis. This is the first time these anthraquinones have been obtained from R. japonicus by HSCCC.