The COVID-19 pandemic starkly exposed vulnerabilities in global food supply chains, highlighting the critical need for resilient, localized alternatives to ensure urban food security. Urban agriculture (UA), which we define as all agricultural output occurring in cities with an urbanization rate exceeding 85%, emerges as a pivotal strategy to mitigate such risks by shortening supply chains, particularly for perishable goods like vegetables and fruits. This study investigates the underexplored role of UA in Guangdong Province, China—a region characterized by rapid urbanization, high population density, and economic dynamism- to assess its contribution to food self-sufficiency. Leveraging a novel classification framework, we categorize Guangdong’s 21 prefecture-level cities into two groups based on an 85% urbanization threshold (2017–2022), distinguishing high-degree urbanized cities (e.g., Shenzhen, Guangzhou) from others. Using panel data, we analyze spatial-temporal patterns in grain, vegetable, and fruit self-sufficiency through geospatial and statistical methods. Key findings reveal pronounced disparities: high-degree urbanized cities exhibit critically low grain self-sufficiency, relying heavily on external supplies, while non-urbanized regions achieve exceptional surpluses. Conversely, vegetables and fruits demonstrate a center-periphery gradient, with peri-urban zones bridging the gap between urban cores and rural surplus hubs. Despite incremental gains in UA productivity, urban yields lag behind non-urban areas for grains and vegetables, though fruit production shows convergence, underscoring UA’s niche potential. These results highlight the indispensability of non-urban regions in sustaining provincial food security while emphasizing UA’s role in fresher, faster urban supply chains. We propose actionable policies, including: (1) integrating farmland protection redlines with UA incentives (e.g., vertical farming subsidies, peri-urban logistics optimization); (2) scaling technology-driven UA (controlled-environment agriculture, digital platforms); and (3) reducing post-harvest losses through urban-centric infrastructure. Our findings advance the discourse on crisis-resilient food systems, offering a replicable framework for high-density regions globally.
Dry reforming of methane (DRM) offers an efficient route to simultaneously convert CH4 and CO2 into synthesis gas (H2/CO), a key intermediate to produce fuels and valuable chemicals. Ni-based catalysts are regarded as the most promising candidates due to their high activity and low cost; however, their stability remains a major obstacle under the DRM conditions. Perovskite-type oxides such as SrTiO3 possess high thermal stability, tunable composition, and strong metal-support interactions, making them ideal to enhance the dispersion and durability of Ni species. In this study, Ni/SrTiO3 catalysts were synthesized via co-precipitation (CP), hydrothermal (HT), and sol-gel (SG) methods, and were comprehensively characterized before and after the reaction. The characterizations revealed that all samples preserved the perovskite framework after reduction and reaction. Among them, Ni/HT-STO and Ni/SG-STO exhibited larger surface areas (18.8 and 13.9 m2·g−1) and higher initial CH4 conversions (66.3% and 68.9%) than Ni/CP-STO (44.8%). However, Ni/HT-STO underwent rapid deactivation, with CH4 conversion decreasing to 21.2% after 60 h due to severe carbon accumulation (12.4 wt%) and notable Ni particle growth. In contrast, the sol-gel derived Ni/SG-STO maintained a higher activity (25.6% after 60 h) with moderate carbon deposition (9.2 wt%) and showed the smallest Ni particle growth of only 2.64 nm (from 14.91 to 17.55 nm), compared with 4.29 nm for Ni/CP-STO (25.83 to 30.12 nm) and 6.08 nm for Ni/HT-STO (27.12 to 33.20 nm). Temperature-programmed surface reaction (TPSR) analysis further revealed that Ni/SG-STO exhibited a more balanced CH4 activation and CO2 dissociation, enabling efficient carbon-oxygen coupling and inhibiting graphitic carbon formation. Overall, these results demonstrate that the sol-gel method effectively enhances the anti-sintering and anti-coking performance of Ni/SrTiO3 catalysts.
The global proliferation of counterfeit biologic medicines poses a growing threat to public health and pharmaceutical integrity. Traditional laboratory-based methods for verifying drug authenticity are often time-consuming, costly, and impractical for real-time or field-based applications. This paper explores the emerging potential of infrared (IR) and Raman spectroscopy for forensic detection and authentication of biologics. While these technologies are currently underutilised in forensic science, advancements in instrumentation and data analysis are rapidly enhancing their sensitivity, portability, and usability. Focusing on protein- and peptide-based therapeutics, the paper reviews the principles and applications of IR and Raman spectroscopy, highlighting their ability to detect structural and compositional differences between authentic and counterfeit biologic drugs. The discussion emphasises the importance of interdisciplinary collaboration between forensic and biopharmaceutical sciences. As counterfeiters become more sophisticated, the integration of non-destructive spectroscopic tools into forensic workflows offers a promising path toward the rapid and reliable screening of biologic drugs in both field and laboratory settings.
Floating offshore wind turbines (FOWTs) offer great potential for harnessing deep-sea wind energy. This study examines the effects of six-degree-of-freedom (6-DOF) platform motions on the dynamic structural responses of a FOWT blade by comparing its performance with a fixed-bottom system. Integrated aero-hydro-servo-elastic simulations for a 5-MW spar-type FOWT were conducted under various design load cases. Results indicate that the floating tower’s first-order natural frequency was about 29% higher than that of the fixed-bottom tower. Platform motions markedly influenced blade flapwise and torsional responses, with the effect intensifying under larger waves. For instance, as the significant wave height increased from 1.70 m to 9.90 m, the differences in peak response between the floating and fixed-bottom systems grew from 0.104 m to 0.363 m for blade-tip flapwise deflection, from 528.1 kN·m to 1817.4 kN·m for the root flapwise bending moment, and from 5.02 kN·m to 18.73 kN·m for the root torsional moment. In contrast, blade edgewise responses showed negligible changes, with peak deflection differences below 0.05 m. Blade loads were more sensitive to wave conditions, while platform motion magnitudes were more affected by wind. These findings offer insights into the load characteristics and structural design of FOWT blades.
Despite its tendency to produce hypotension, propofol is used widely to induce general anesthesia and to facilitate endotracheal intubation in critically ill patients. Both dose reduction and routine co-administration of vasopressors have been used to offset this unfavorable hemodynamic effect in this subset of individuals. There are potential problems associated with each of these corrective measures, however, and criticism of other intravenous hypnotics used for this purpose—particularly etomidate—may be unwarranted. Choice of the appropriate pharmacology to induce anesthesia to assist with intubation should likely be based on individual clinical assessment, together with an understanding of the drug profile and realistic adverse effects.
