A 28-day experiment was conducted to evaluate the effects of dietary vitamin A (VA) levels on intestinal morphology and immune performance of goslings. Healthy, one-day-old goslings (360) of similar body weight were randomly divided into six groups fed diets supplemented with 0 (A), 3 000 (B), 6 000 (C), 9 000 (D), 12 000 (E), and 15 000 (F) IU/kg VA. Compared to group A, villus height in group D, as well as villus width and crypt depth in groups C and D were increased in the duodenum (quadratic effect, P < 0.05); villus height and villus width in groups B, C, D and E, and crypt depth in groups C and D were increased in the jejunum (quadratic effect, P < 0.05); villus height and villus width in groups C and D, and crypt depth in groups B, C, D, E and F, as well as muscular layer thickness in group D were increased in the ileum (quadratic effect, P < 0.05). Serum immunoglobulin A in groups B, C, D and E, and serum immunoglobulin G levels in groups D and E were higher than in group A (quadratic effect, P < 0.05). Serum interleukin-1 (quadratic effect, P < 0.05) and interleukin-6 (linear and quadratic effect, P < 0.05) levels in groups D and E, and serum interleukin-2 level (quadratic effect, P < 0.05) in group C were higher compared to group A. In conclusion, dietary supplementation with 6 000-9 000 IU/kg VA improved intestinal morphology and immune performance of goslings.

We aim to create a feasible quantitative method to calculate the energy efficiency of building designs that are carbon-neutral and to develop a workable way of calculating energy efficiency in buildings that achieve carbon neutrality and the system for such a building’s design energy efficiency function. This paper first clarifies the idea of the design energy efficiency function for a carbon-neutral building over its whole life cycle. Subsequently, through the efficient analysis of carbon-neutral design dimension measures, this paper summarizes and integrates the mature theories of various disciplines, puts forward the energy efficiency function model of carbon-neutral design background, propulsion, and coverage, and implements the energy efficiency function model of carbon-neutral design in the whole life cycle of buildings. The index value of a building’s carbon emission factor is established based on the carbon accounting factor published by the Intergovernmental Panel on Climate Change, and a carbon neutrality energy efficiency model for buildings over the duration of their whole life cycle is constructed. The results were as follows. 1. Technology energy efficiency is far better than scale energy efficiency and comprehensive energy efficiency. 2. The better the energy efficiency value inside the building stage, the less consumption and the higher the production. 3. Construction is when technical energy is used the least. This paper refers to a systematic design method that makes the level of building carbon neutrality design technologically advanced with the aid of all types of big data related to the building life cycle and various innovative design theories in order to fully represent the fundamental level, development potential, and the effectiveness of choosing the strategy of building carbon neutrality.

The construction industry has become one of the main drivers of the increase in carbon emissions and subsequent climate change. In this study, we focused on building carbon neutrality design and used CiteSpace V.6.2.R2 to conduct bibliometric analysis of published papers (2008–2023). After the initial screening, 280 pieces of relevant literature were obtained, including reviews, research papers, and case studies. Following further screening and excluding duplicate literature articles, 50 pieces of literature were ultimately selected as references for this paper, covering various aspects of key scientific issues, implementation approaches, and emerging research frontiers in carbon-neutral design for buildings. The research results show that significant progress has been made in energy conservation, materials, structures, systems, and operations in the research on carbon-neutral design for buildings. However, there are still issues, such as unclear implementation paths for carbon-neutral design, incomplete lifecycle assessment of carbon-neutral design, and high cost of carbon neutrality technologies in current research. Therefore, further research on the overall concept of carbon-neutral design, the progress and implementation of carbon neutrality technologies, and the integration of carbon-neutral design with sustainable development concepts are necessary. To sum up, this paper presents a thorough overview of the advancements in carbon-neutral design for buildings, examines the existing research challenges, and suggests potential avenues for future research. This paper’s findings can provide guidance for researchers, policymakers, and practitioners to promote the development and application of carbon-neutral design for buildings and to achieve sustainable development goals.