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The Middle Jurassic Walloon Subgroup of Daandine gas field contains numerous coal seams with abundant coalbed methane (CBM) resources. However, the vertical gas content distribution of these coal seams is unclear currently, as well as its influencing factors, affecting the formulation of CBM exploration and exploitation strategy. For this purpose, using diverse geologic, experimental, and engineering data from recent exploration and development, this article ascertains the vertical coalbed gas content distribution in the Daandine gas field and discusses how the geological factors affect it. The results show that the coalbed gas contents have two basic trends as the depth increases: (1) increase, and then decrease; (2) increase. The former trend is dominant, and the inflection point occurs in the coal groups within or close to the Tangalooma Sandstone Formation. The correlation analysis shows that the macerals have little influence on the vertical coalbed gas content distribution. The moisture contents affect the adsorption capacity of coalbeds and show a negative correlation with the gas contents, and coal groups with higher moisture contents generally have lower gas contents. Three sets of independent gas-bearing systems exist in the Walloon Subgroup, and the coalbed gas content-depth relationship is relatively independent among different gas-bearing systems. The better the caprock condition, the higher the gas content, which is particularly evident in the coals of Condamine group. The permeabilities show a significant effect on the coalbed gas contents of Daandine coals. The coal groups within or close to the Tangalooma Sandstone Formation have higher permeabilities, as well as higher gas contents, and they are positively correlated. The reason is that the CBM in the study area is dominantly microbial in origin, and the higher permeability coals are conducive to the introduction of more microbial consortia into the coal seams, enhancing the generation of secondary biogenesis methane. [ABSTRACT FROM AUTHOR]

Gestational diabetes mellitus (GDM) is one of the common complications during pregnancy. Numerous studies have shown that GDM is associated with a series of adverse effects on both mothers and offspring. Due to the particularity of pregnancy, medical nutrition treatment is considered to be the first choice for the treatment of GDM. This contribution reviews the research progress of medical nutrition treatment in GDM, summarizes the international recommendations on the intake of various nutrients and the influence of nutrients on the prevalence of GDM, and the improvement effect of nutritional intervention on it, in order to provide references for research in related fields of GDM and the targeted development of enteral nutrition. [ABSTRACT FROM AUTHOR]

The Belt and Road (B&R) initiative creates a highly competitive and dynamic environment and cooperation network for construction projects in specific regions. By using the experience of other countries, construction professionals can be well-equipped with management skills for solving intractable problems during the project management process of a construction project. Value management (VM) is a systematic team decision-making methodology used to achieve the best project value, but it is rarely applied in developing regions along the B&R. This study aims to identify critical success factors for the implementation of VM in construction projects in both developed and developing regions along the B&R. Six focus groups targeting three groups of regions were conducted, including advanced VM developed regions (Regions 1), advanced VM developing regions (Regions 2), and unadvanced VM developing regions (Regions 3). Three main groups of critical success factors were identified by using contextual analysis: technical process, team behaviors, and outcomes. By comparing VM in advanced VM regions (Regions 1 and Regions 2) and traditional team decision-making in unadvanced VM regions (Regions 3), the study revealed that (1) practitioners in Regions 1 applied VM to achieve project success with a logical process and positive team behaviors, although several problems were also encountered; (2) surprisingly, in some technical respects, VM practitioners in Region 2 performed better than those in Regions 1, but positive team behaviors were still not emphasized; and (3) inefficient traditional decision-making activities with illogical technical processes and negative team behaviors in Regions 3 often led to poor project outcomes. A propositional model is established based on the identified critical success factors and comparison results among the three groups of regions. Finally, several practical recommendations are proposed to ensure effective VM application and promotion in both developed and developing regions along the B&R. In the developing countries that participated in the Belt and Road initiative, poor performance is not uncommon for megaconstruction projects with multiple stakeholders due to poor problem-solving strategies. This research revealed that value management practitioners in developed regions could achieve good project outcomes by applying value management with a logical framework and positive team behaviors, but they have not yet found a good way to resolve problems in terms of time constraints, no follow-up actions, and duplicate information from the public. VM practitioners in some of the developing regions put much effort into VM application, but the poor function analysis and insufficient conflict management, commitment, and transparency still impacted the final project outcomes negatively. Various problems such as no information analysis, serious corruption, and limited participation were encountered in illogical traditional team decision-making activities in developing regions, which significantly destroyed stakeholder outcomes and project performance. This research explores the insufficient value management practices in both developed and developing regions along the B&R, which provides empirical evidence to constriction professionals to update their VM/traditional team decision-making strategies and find out the best ways to conduct VM logically and effectively for improving final project outcomes. [ABSTRACT FROM AUTHOR]