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This study aims to improve the hydrolysis and degradation of primary sludge by using wild-type enzymes (protease and lipase) and establishing the optimal enzymatic cocktail ratio. Primary sludge from three wastewater treatment plants (WWTPs) in Korea (Ulsan, Pohang, and Busan) were subjected to enzymatic hydrolysis. Protease and lipase were isolated from enzyme-producing microorganisms cultured from secondary sludge collected at 8 different digester sites in Korea. Primary sludge degradation through enzymatic hydrolysis was monitored by measuring the reduction in the volatile suspended solids (VSS) content of the sludge and enzyme cocktail mix for 72 h at 40oC and pH 7.0. The enzymatic cocktail of Ulsan primary sludge treated with protease to lipase at a ratio of 1:3 was found to be optimal at 33.3% VSS reduction. Biochemical methane potential (BMP) tests were employed to the optimal enzyme cocktail to measure the potential of the hydrolyzed substrate for further degradation (VSS reduction) and bioconversion to biogas using 125 mL serum bottles as anaerobic reactors for 30 days. BMP tests showed that there was an increase in biogas production by 84.1%, methane production by 89.8%, and methane yield by 9.6%. Methane production rate was also increased. The significant VSS concentration reduction and higher biogas and methane yield of the enzyme-treated primary sludge correlate to the fact that the complex polymeric organic materials were degraded leading to efficient utilization by the microorganisms in the anaerobic digestion process. [ABSTRACT FROM AUTHOR]

Abstract Economic growth and urbanization have reduced urban land resources to the point that such resources are now, in some cases severely, limited. In order to support sustainable development and to solve the problem of land shortages in urban areas, one practical solution is the shifting of land usage from above the surface to underground. However, in most countries, including Korea, the cadastral system cannot adequately handle the legal, administrative, and technical aspects of the registration and maintenance of underground parcels. The main purpose of this research, therefore, was to propose a conceptual registration framework for 3D underground parcels. In order to do that, issues of unregistered underground space were summarized, and the legal, administrative, and technical limitations were revealed. In consideration of these limitations, the registration framework for 3D underground parcels is herein proposed. This framework consists of four steps: 1) preparation of 3D underground parcel data with consideration for information regarding 3D underground cadastral surveying and building-components; 2) definition of 3D underground parcels, based on deep underground regulation in Korea and the registration extent, registration unit, absolute height and relative height of systems; 3) 3D underground cadastral registration according to the three types of cadastral maps and land registration; 4) registration of 3D underground rights, such as ownership and sectional superficies of the 3D underground parcel. Finally, in order to implement the proposed registration framework for a 3D underground parcel, legal, administrative, and technical improvements are proposed. Highlights • The exiting cadastral system cannot fully support land administration related to 3D underground space in most countries. • A registration framework for 3D underground parcel is required to efficiently manage underground properties in urban area. • The proposed registration framework for the 3D underground parcel establishes the workflow of the 3D underground cadastral system. [ABSTRACT FROM AUTHOR]

What roles do grassroots movements play in urban change? While many studies have focused on the substantive effects of grassroots movements in specific times and places, few have examined how a movement sustains its long-term development through changing sociopolitical and urban circumstances, and how this long-term, historical evolvement affects urban change. In exploring the development of the community movements over half a century in Korea, this paper examines the community movements’ various incarnations, from its function as a repository for early protest activism to recent collaborative efforts in response to the complex transformation of political and social systems and the subsequent development of urban and regional policies. Throughout this transformation in Korea, grassroots community movements have acted as a critical social catalyst, exerting major influence on the country’s shift from a prototypical modernist planning structure to a decentralised, participatory system. [ABSTRACT FROM AUTHOR]

The topic of local and community governance has garnered increasing attention from researchers in recent years, with the resulting assessments generally identifying both the advantages and obstacles. On the positive side, collaborative community governance is often viewed as a new participatory space facilitating democratic practices with favourable social and relational outcomes. Conversely, the issues of power imbalances and the continued hierarchical influence of the central government are often cited as obstacles to genuine public engagement and horizontal collaboration among diverse actors. In particular, numerous studies argue that the governance structure and initial motivation exert significant influence over the governance processes and outcomes due to the different prioritisation of goals and strategies. Such considerations demonstrate the need for additional comparative studies in diverse contexts. In addition to addressing the limitation of the existing process-focused evaluations, this study proposes an analytic framework of collaborative community governance that identifies the multiple relationships between institutional setting, governance process and outcomes, and examines two community-building initiatives in Korea. The findings demonstrate that collaborative community governance worked as an experiential incubator for individual transformation, social and relational resource building and political empowerment. The comparative analysis of two different collaborative forms reveals that differences in structure and the mode of communication resulted in building different types of relational capital (bonding vs bridging). The lack of preliminary discussions and arrangement for institutional design is highlighted as a source of problems such as excessive dependency on particular communication modes, opaque system of representation and asymmetrical development of relational resources. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the association between initial fibrinogen levels and massive transfusion (MT) in emergency department (ED) patients with primary postpartum hemorrhage (PPH). Methods: This retrospective study was conducted in the ED of a university-affiliated, tertiary referral center from January 2004 to August 2023. Patients were divided into two groups: the MT group, which included those who received a transfusion of 10 or more units of packed red blood cells within the first 24 h, and the Non-MT group. Results: Out of the 364 patients included in the study, 97 (26.6%) required MT. Fibrinogen, shock index, and lactate were independently associated with MT (odds ratio [OR] 0.987; 95% confidence interval [CI] 0.983–0.991; p < 0.001, OR 7.277; 95% CI 1.856–28.535; p = 0.004, and OR 1.261; 95% CI 1.021–1.557; p = 0.031, respectively). The area under the receiver operating characteristic curve for fibrinogen, shock index, and lactate in predicting MT was 0.871 (95% CI 0.832–0.904; p < 0.001), 0.821 (95% CI 0.778–0.859; p < 0.001), and 0.784 (95% CI 0.738–0.825; p < 0.001), respectively. When the cutoff value of fibrinogen was 400 mg/dL, both the sensitivity and negative predictive values for predicting MT were 100.0%. When the cutoff value of fibrinogen was 100 mg/dL, the specificity and positive predictive values were 91.8% and 70.7%, respectively. Conclusion: The initial fibrinogen levels were independently associated with the need for MT in ED patients with primary PPH. [ABSTRACT FROM AUTHOR]