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Abstract The Shibing Karst constitutes a pivotal component of the "South China Karst," and its ecosystem health integrity crucially influences the Outstanding Universal Value (OUV) of the corresponding Natural World Heritage (NWH). Consequently, robust ecosystem health assessment (EHA) is imperative for the judicious conservation and management of this heritage, as well as for the sustainable progression of the region. This research assessed the health of the Shibing Karst ecosystem from 2004 to 2020 by employing changes in landscape patterns through the Vigor-Organization-Resilience-Ecosystem Services (VORS) model. Spatial autocorrelation was employed to discern the spatial coherence and evolutionary patterns of ecosystem health, whereas a geo-detector ascertained the pivotal determinants impacting regional ecosystem vitality. The findings revealed that: (1) The landscape patterns distribution in the study area exhibited considerable constancy, primarily comprising forest land, with a rising trajectory in construction land and water, juxtaposed with a recession in shrubland, grassland, paddy land, and dryland expanses. (2) From 2004 to 2020, the ecosystem of the study area maintained its health and remained stable, with mean values of 0.8303, 0.7689, 0.6976, and 0.7824, respectively, showing an evolutionary trend of an initial downtrend trend followed by an upswing, with 2016 marking a pivotal juncture. (3) Spatial clustering analysis highlighted significant clustering characteristics of ecosystem health, with a nominal decrease in the Global Moran's I index from 0.666 to 0.665, which is indicative of a subtle decrease in clustering over time. High-high clustering areas were predominantly located within the World Heritage Site (WHS), while low-low clustering areas were mainly distributed in the southeastern part of buffer zone. (4) Land use and cover change (LUCC) and Ecosystem Services (ESs) were identified as the primary indexes of EHA, with Ecosystem Resilience (ER), Ecosystem Vigor (EV), and Ecosystem Organization (EO) exerting relatively mild influences. This study provides a scientific framework for policymakers in local governance to devise strategies for ecosystem conservation and management, enhances the analytical perspective on the integrity and conservation of Karst Natural World Heritage (KNWH).

Abstract Background Patients with overweight/obesity and type 2 diabetes are encouraged to lose weight, but not all losing weight gain better cardiovascular health, especially old adults. The change in skeletal muscle mass (SMM) could be the key that explains the heterogenous cardiovascular effects of weight loss. This study aims to assess whether the cardiovascular effects of weight loss vary for those gaining skeletal muscle along with weight loss. Methods The old adults with overweight/obesity and type 2 diabetes in the Look AHEAD study having muscle measurement from dual‐energy X‐ray absorptiometry were included. Based on the weight change (WC) and SMM change (SMMC) between baseline and the 4‐year follow‐up, participants were allocated into three groups—weight gain (WG) group, weight loss with muscle loss (WL‐ML) group and weight loss with muscle gain (WL‐MG) group. Cox proportional hazards regression was performed to evaluate the cardiovascular risk of those gaining or losing SMM with weight loss compared with those gaining weight. Among the participants with weight loss, the ratio of SMMC/WC was calculated, and the association of SMMC/WC with primary cardiovascular outcome was assessed. Results A total of 491 participants were included in the study with an average age of 64.56 ± 3.81 years old. A total of 47.0% were male and 49.9% were from the intensive lifestyle intervention arm. Based on their WC and SMMC, 43 were assigned to the WG group, 373 to the WL‐ML group and 75 to the WL‐MG group. Over a follow‐up of almost 10 years, 97 participants encountered the primary endpoint. The WG group had the highest incidence of 25.59%, the WL‐MG group had the lowest incidence of 9.33% and the WL‐ML group had 21.18% (P = 0.040). In the fourth adjusted Cox model, the WL‐MG group achieved significantly decreased odds of the primary endpoint compared with the WG group (hazard ratio [HR] 0.33, 95% confidence interval [CI] [0.12, 0.87], P = 0.026), whilst the WL‐ML group did not (HR 0.91, 95% CI [0.47, 1.78], P = 0.670). Among the participants with weight loss, when SMMC/WC reached around 50%, this HR soared to approximately two‐fold. Conclusions The participants gaining SMM along with weight loss achieved the lowest odds of adverse cardiovascular events, whilst those who lost SMM along with weight loss had comparable cardiovascular risk with those gaining weight. The more muscle lost during weight loss, the greater the harm. The cardiovascular effects of weight loss were modulated by whether the participants gained SMM meanwhile losing weight.

Abstract Karst World Heritage Site (KWHS) combines high-grade landscape resources and a fragile ecological environment. As an essential tool for heritage conservation and maintaining local interests, its buffer zone is primarily located in remote villages, a crucial and challenging area for rural revitalization. The conflict between heritage conservation and development is particularly acute at the site. How to deal with the relationship between the heritage site’s OUV conservation and the buffer zone's tourism industry development and realize the synergy between the two subsystems? Few studies have focused on it. There is an urgent need to explore the synergistic mechanism of the KWHS's OUV conservation and the buffer zone's tourism industry development. Accordingly, this study takes the Libo-Huanjiang KWHS, one of the 'South China Karst' series of heritage sites, as a case study. The coupling coordination degree model, gray correlation analysis (GCA), and Geographic Information System (GIS) spatial analysis are used. The results show that: (1) There is a synergistic effect between the Libo-Huanjiang KWHS's OUV conservation and its buffer zone's tourism industry development, showing a favorable trend. The mean value of the coupling coordination degree increased from 0.57 in 2015 to 0.63 in 2020, and the overall situation improved from barely coupling coordination state to primary coupling coordination. (2) Influenced by the main driving factors, such as NDVI, landscape dominance, government support for tourism development, tourists' satisfaction, and residents' support, the coupling coordination of the four tourist scenic areas in the study area differed slightly in 2015 and 2020. Yaoshan Ancient Village Scenic Area is the highest in both years, increasing from 0.69 to 0.81, followed by the Mengliu Buyi Scenic Area (0.59), Wanmu Meiyuan Scenic Area is relatively stable with a slight increase, and Lianshanwan Scenic Area (0.45) is the lowest. (3) The four dimensions of ecological resources, policy drivers, economy drivers, and social facilitators work together to create a synergistic mechanism between the KWHS's OUV conservation and the buffer zone's tourism industry development. Future research can promote synergy between the two by formulating a comprehensive plan, encouraging sustainable tourism, establishing a diversified tourism industry, strengthening heritage education and training, enhancing community participation, and reinforcing stakeholder cooperation.

Background An association between variability of cardiovascular risk factors and cardiovascular events has been reported. We examined whether intensive lifestyle intervention (ILI) for weight loss decreased variability of cardiovascular risk factors with a view to additional cardiometabolic benefits. Methods and Results This study was a post hoc secondary analysis of the Look AHEAD (Action for Health in Diabetes) study. Cardiovascular risk factors were measured at 1‐year intervals for 4 years in 4249 adults with overweight or obesity and type 2 diabetes who were randomly assigned to ILI or diabetes support and education. Long‐term variability was defined as the SD of cardiovascular risk factors during 4‐year follow‐up. At multiple linear regression analysis, compared with the diabetes support and education group, the ILI group was associated with reduced variability of fasting blood glucose (β=−1.49 [95% CI, −2.39 to −0.59]), total cholesterol (β=−1.12 [95% CI, −1.75 to −0.48]), and low‐density lipoprotein cholesterol (β=−1.04 [95% CI, −1.59 to −0.49]), as well as increased variability of systolic blood pressure (β=0.27 [95% CI, 0.00–0.54]). No significant effect of ILI was found on the variability of diastolic blood pressure (β=−0.08 [95% CI, −0.22 to 0.05]). Conclusions Among adults with overweight or obesity and type 2 diabetes, ILI may reduce long‐term variability of fasting blood glucose, total cholesterol, and low‐density lipoprotein cholesterol. Our results support that ILI should be recommended to individuals with diabetes as part of management of long‐term glycemic and blood lipid control.

Abstract Aims/introduction Weight variability is associated with cardiovascular outcomes in diabetic patients. However, whether the guideline‐recommended intensive lifestyle intervention (ILI) will affect this association in overweight or obese adults with diabetes is not well established. Materials and Methods In 3,859 participants from the Action for Health in Diabetes (Look AHEAD) trial, the associations of 4 year weight variability measured by variability independent of the mean (VIM) with major adverse cardiovascular event (MACE) and secondary outcomes in ILI and diabetes support & education (DSE) arm were evaluated. Results During a median follow‐up of 9.6 years, 255 (12.9%) participants in the ILI arm and 247 (13.2%) participants in the DSE arm developed MACE. Participants with the highest quartile of weight variability (VIM Q4) experienced a 2.23‐fold higher risk of MACE compared with the lowest quartile (VIM Q1) in the DSE arm (hazard ratio [HR] 2.23; 95% CI 1.51–3.30). Compared with the lowest weight variability (VIM Q1), participants with the highest weight variability (VIM Q4) were associated with higher risks of secondary cardiovascular composite outcome (HR 1.88; 95% CI 1.20–2.95), all‐cause mortality (HR 3.19; 95% CI 1.75–5.82), and myocardial infarction (HR 1.95; 95% CI 1.12–3.37) in the DSE arm. Conclusions Among the overweight or obese individuals with type 2 diabetes mellitus, rising weight variability was independently associated with increased MACE risks in the DSE arm. Therefore, a guideline‐recommended ILI strategy for weight loss should be adopted to improve cardiovascular outcomes without worrying about the effect of weight fluctuations.

Earth‐abundant manganese (Mn) compounds have multifarious valence states that make Mn advantageous for electrochemical energy storage applications. Benefiting from the unity of opposites in redox chemistry, a novel aqueous all‐Mn energy storage device (AMESD) based on the redox chemistry of Mn2+ is proposed, which is a simple‐structured battery that can be initially assembled by two bare carbon fiber cloths (CFCs) and the electrolyte. Moreover, the effects of electrolyte optimization and the modification of CFCs on the energy storage performance of the novel battery are discussed. The device based on N‐doped porous CFCs achieves the highest areal capacity of 1.46 mAh cm−2 (≈152.1 mAh g−1), along with an energy density of 1.10 mWh cm−2 and a power density of 9.66 mW cm−2. More impressively, the charge–discharge cycles at a capacity of 0.33 mWh cm−2 are performed 40 000 times and it can maintain a high‐capacity retention rate of 93.5%. Even at a low current of 1 mA cm−2, the capacity retention rate after 100 cycles is maintained to 86%. Herein, a new option for low‐cost, ultrastable aqueous battery design is provided and the possibility of Mn‐based anodes for energy storage applications is explored.

Abstract In recent decades, World Heritage Sites (WHSs) have faced external severe threats in the context of global economisation and urbanisation. The buffer zone as a conservation layer and management tool for WHSs has attracted increasing scholarly attention and debate. However, there is limited understanding of buffer zones’ social and ecological role in the conservation of World Natural Heritage Sites (WNHSs) and a lack of summary of research progress on buffer zones. To fill this gap, this study systematically reviews the existing knowledge and research gaps on buffer zones in WNHSs worldwide. We used a systematic literature review framework of Search, Assessment, Synthesis and Analysis (SALSA) through the WoS and CNKI databases to obtain 188 articles that met the inclusion criteria. The aim was to analyze the temporal and regional distribution of publications, types of studies, main processes and landmark achievements, gaps, and implications for future research. Results indicated that: (1) there is an overall upward trend in the number of publications, reaching a maximum in 2020, with the most published in Asia and Europe. The research process presents two main categories of ecologically and socially oriented. (2) The main landmark achievements include theoretical research, technology and methods, model construction, benefit monitoring and evaluation, experimental demonstration, etc. Among them, theoretical research is the most numerous (58.51%). (3) On this basis, 8 key scientific issues are summarised. Reviewing the research progress and summarising the critical scientific issues will provide practical guidance for the effective implementation of the role of buffer zones in global WNH conservation, especially for karst WNHSs with fragile ecological environments. (4) The future of Karst WNH conservation should be based on the effect of human-land relationship in promoting heritage protection. Examining the institutional factors of ecological problems and the management of degraded ecosystems from a socio-economic perspective. The purpose is to seek a socio-ecological system that is composed of the social, economic, ecological and cultural dimensions of the buffer zone. Focus on the coupling between eco-industrial development and WNH conservation, and strengthen buffer zone communities’ adaptive and collaborative management. Explore techniques and methods of conservation adapted to the characteristics of the fragile ecosystem of karst itself, and conduct experimental demonstrations.

Abstract In the context of integrating culture and tourism, world heritage tourism research has become a focus in tourism research in recent years. There are increasing discussions in academic circles on the content and methods of this field. Clarifying the knowledge system of research is conducive to dialogue with international theoretical frontiers and integrating, analyzing, and predicting the progress and lineage from a more comprehensive perspective. Still, few studies on the knowledge system of world heritage tourism research have been conducted. To fill this gap, this study uses the SSCI and SCI sub-databases of Web of Science Core Collection as the data source with the help of CiteSpace and VOSviewer software to measure the knowledge system of world heritage tourism research. A bibliometric analysis of 567 publications between 1992 and 2020 was conducted to construct a framework of a knowledge system based on literature statistics and content analysis, revealing the geographic research regions, theories and methods, themes and contents, trend evolution, and future research inspiration. The results show that: (1) the number of publications tends to increase gradually, with the highest in 2019. The authors and research institutions are mainly concentrated in Europe, America, East Asia. China has the highest publications. More literature on cultural heritage as a geographical study area than natural heritage. (2) The research themes, objects, and methods of the sample literature have become more diversified with the advancement of the research stage. The literature on multi-stakeholder research is the largest, followed by tourism impacts and research on World Heritage Sites’ resource management techniques and methods. These studies provide a multifaceted interpretation of the sustainable development of World heritage tourism, mainly from the perspectives of both supply and demand. However, the theoretical system is still incomplete. (3) Future research should strengthen the theoretical system construction, research innovation, cooperation, and research exchange in world heritage tourism research. Pay more attention to the research on the pluralistic value system of world heritage. Focus on exploring research on world heritage tourism’s resilience and localization dilemmas under the impact of the New Crown epidemic. To reveal the synergistic mechanisms and paths of diversified livelihoods of World Heritage Sites’ residents in ecologically fragile and impoverished areas.

In this paper, an elastoplastic analysis model of thin-walled circular tubes under the combined action of axial force and torque is discussed. Based on the von Mises yield criterion and the assumption of isotropic linear hardening, the methods of stress path and strain path loading are analyzed to study the effect of combined tensile-torsional loading path on thin-walled circular tubes. A finite element model is used to analyze the loading path effect on thin-walled circular tubes. A series of tensile and torsional tests are also carried out on 304 stainless steel thin-walled circular tubes using a universal testing machine. In addition, the consistency of the selected material with the von Mises yield criterion, the assumption of isotropic linear hardening, and other classical elastoplastic mechanics are verified. The theoretical calculation results, the numerical analysis results, and the experimental test results are analyzed and compared. The “primary effect” influenced by the stress path and the “recency effect” affected by the strain path are proved, and their application prospects are discussed. The influence of tensile-torsional loading path on the final stress and strain states of thin-walled circular tubes after entering the plastic deformation stage is concretely demonstrated, facilitating the understanding of the principles of the aforementioned two effects. The investigation for a general principle concerning the effect of loading history on the mechanical behavior of engineering materials, based on the classical plastic mechanics, has an important theoretical significance. It is of great theoretical importance for advancements in plastic yield theory and the establishment of more accurate loading conditions suitable for specific materials in engineering practice.

BS700 high-strength steel is widely used in engineering. Welding residual stress during the manufacturing process has a significant influence on the structural safety and service life of steel structures. In this study, the residual stress of a BS700 butt-welded box section axial compression member was studied by the blind-hole method, its distribution law was summarized, and a residual stress distribution model was established. By establishing a finite element model considering initial geometric imperfection and residual stress, the influence of residual stress on the stability of axial compression members was analyzed. The results illustrated that the residual tensile stress near the weld in the welded box section axial compression members was the largest: the average residual tensile stress reached 76.6% of the measured steel yield strength, the residual tensile stress at the roof and web were almost the same, and the residual tensile stress at the corner was approximately 11.6% of the measured yield strength. The residual stress had a different influence on the stability factor of the axial compression members with different width-thickness ratios, and the influence decreased with the increase in the width-thickness ratio. In addition, when the slenderness ratio of members ranged between 20 and 70, the residual stress had a significant influence on the stability of members, while outside that interval, the influence was relatively small.