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Skin expands and regenerates in response to mechanical stretch. This important homeostasis process is critical for skin biology and can be exploited to generate extra skin for reconstructive surgery. Atmospheric oxygen uptake is important in skin homeostasis. However, whether and how cutaneous atmospheric oxygen uptake changes during mechanical stretch remains unclear, and relevant research tools to quantify oxygen flux are limited. Herein, we used the scanning micro-optrode technique (SMOT), a non-invasive self-referencing optical fiber microsensor, to achieve real-time measurement of cutaneous oxygen uptake from the atmosphere. An in vivo mechanical stretch-induced skin expansion model was established, and an in vitro Flexcell Tension system was used to stretch epidermal cells. We found that oxygen influx of skin increased dramatically after stretching for 1 to 3 days and decreased to the non-stretched level after 7 days. The enhanced oxygen influx of stretched skin was associated with increased epidermal basal cell proliferation and impaired epidermal barrier. In conclusion, mechanical stretch increases cutaneous oxygen uptake with spatial-temporal characteristics, correlating with cell proliferation and barrier changes, suggesting a fundamental mechanistic role of oxygen uptake in the skin in response to mechanical stretch. Optical fiber microsensor-based oxygen uptake detection provides a non-invasive approach to understand skin homeostasis.

RGB-D (depth) Salient Object Detection (SOD) seeks to identify and segment the most visually compelling objects within a given scene. Depth data, known for their strong discriminative capability in spatial localization, provide an advantage in achieving accurate RGB-D SOD. However, recent research in this field has encountered significant challenges due to the poor visual qualities and disturbing cues in raw depth maps. This issue results in indistinct or ambiguous depth features, which consequently weaken the performance of RGB-D SOD. To address this problem, we propose a novel pseudo depth feature generation-based RGB-D SOD Network, named PDFNet, which can generate some new and more distinctive pseudo depth features as an extra supplement source to enhance the raw depth features. Specifically, we first introduce an RGB-guided pseudo depth feature generation subnet to synthesize more distinctive pseudo depth features for raw depth feature enhancement, since the discriminative power of depth features plays a pivotal role in providing effective contour and spatial cues. Then, we propose a cross-modal fusion mamba (CFM) to effectively merge RGB features, raw depth features, and generated pseudo depth features. We adopt a channel selection strategy within the CFM module to align the pseudo depth features with raw depth features, thereby enhancing the depth features. We test the proposed PDFNet on six commonly used RGB-D SOD benchmark datasets. Extensive experimental results validate that the proposed approach achieves superior performance. For example, compared to the previous cutting-edge method, AirSOD, our method improves the F-measure by 2%, 1.7%, 1.1%, and 2.2% on the STERE, DUTLF-D, NLPR, and NJU2K datasets, respectively. [ABSTRACT FROM AUTHOR]

DC converter stations have a high voltage level, a long transmission distance, and complex internal equipment, and contain power electronic devices, which seriously endanger the stable operation of the system itself and the active distribution network at the receiving end when faults occur. Accurate fault analysis and diagnosis are critical to the safe and stable operation of power systems. Traditional fault diagnosis methods often rely on a single source of information, leading to issues such as insufficient information utilization and incomplete diagnostic scope when applied to DC transmission systems. To address these problems, a fault diagnosis method for converter stations based on preliminary identification of the fault range and the fusion of evidence information of the switch signal and electrical quantity is proposed. First, the preprocessing of converter station sequential event recording (SER) events and a statistical analysis of event characteristics are completed to initially determine the range of the fault.Then, a fuzzy Petri net model and a BP neural network model are constructed on the basis of the fault data from a real-time digital simulation system (RTDS), and the corresponding evidence information of the switch signal and electrical quantity are obtained via iterative inference and deep learning methods. Finally, on the basis of D-S evidence theory, a comprehensive diagnosis result is obtained by fusing the switch and electric evidence information. Taking the fault data of a DC converter station as an example, the proposed method is analyzed and compared with the traditional method, which is based on single information. The results show that the proposed method can reliably and accurately identify fault points in the protected area of the converter station. [ABSTRACT FROM AUTHOR]

With new sulphur oxides emission limits carried out in 2020, multiple desulphurisation methods have been proposed. The main desulphurisation scrubber systems were chosen and investigated using life cycle assessment. The whole system life is divided into the construction and operational phases. Three different systems classified by desulphurisers, namely, seawater, NaOH, and Mg-based systems, were modelled in GaBi software. Moreover, environmental, economic and energy aspects (3E model) were introduced for further analysis. Through this study, some conclusions have been drawn. As for the environmental aspect, the seawater system has the most pleasing performance since the primary emissions come from 1.24E+03 kg CO2 and 1.48E+01 kg chloride. The NaOH system causes 1000 times more emissions than the seawater. The Mg-based system has less pollution than the NaOH system, with 5.86E+06kg CO2 and 3.86E+03 kg chloride. The economic aspect is divided into capital expenditure (CapEx) and operational expenditure (OpEx) to estimate disbursement. The seawater system also has the most favourable cost appearance, which takes 1.7 million dollars without extra desulphuriser expenses, based on 10MW engine flue gas treatment. The next is the Mg-based system, which cost 2 million dollars in CapEx and $ 1200/year in OpEx for the desulphuriser. NaOH uses about 2.5 million dollars for construction and $ 30000/year in desulphuriser. As for the energy aspect, the seawater and Mg-based systems use less non-renewable energy than the NaOH system in the construction phase. In conclusion, the seawater system shows the best performance and could be an alternative in SOx control technologies. This study sheds light on the comprehensive evaluation of marine environmental protection technologies for further optimisation.

Ethereum smart contracts are programs that can be collectively executed by a network of mutually untrusted nodes. Smart contracts handle and transfer assets of values, offering strong incentives for malicious attacks. Intrusion attacks are a popular type of malicious attacks. ContractGuard, the first intrusion detection system (IDS) was proposed to defend Ethereum smart contracts against such attacks. Like IDSs for conventional programs, ContractGuard detects intrusion attempts as abnormal control flow. However, existing IDS techniques or tools are inapplicable to Ethereum smart contracts due to Ethereum’s decentralized nature and its highly restrictive execution environment. To address these issues, ContractGuard was designed by embedding it in the contracts. At runtime, ContractGuard protects the smart contract by monitoring the context-tagged acyclic path of the smart contract. As ContractGuard involves deployment overhead and deployment overhead. It was optimized under the Ethereum Gas-oriented performance model to reduce the overheads. The experimental results show that this work can effectively detect 83% of vulnerabilities, ContractGuard only adds to 36.14% of the deployment overhead and 28.27% of the runtime overhead.

Background: Full‐thickness skin grafts are widely used in plastic and reconstructive surgery. The main limitation of skin grafting is the poor textural durability and associated contracture, which often needs further corrective surgery. Excessive inflammation is the main reason for skin graft contractions, which involve overactivation of myofibroblasts. These problems have prompted the development of new therapeutic approaches, including macrophage polarization modulation and stem cell–based therapies. Currently, adipose‐derived stem cells (ASCs) have shown promise in promoting skin grafts survival and regulating macrophage phenotypes. However, the roles of ASCs on macrophages in decreasing skin grafts contraction remain unknown. Materials and Methods: Rat adipose‐derived stem cells (rASCs) were isolated from rat inguinal adipose tissues. Full‐thickness skin graft model was constructed on male rats divided into control group and rASCs treatment group. Skin graft was assessed for concentration, elasticity modulus and stiffness. Rat bone marrow‐derived macrophages (rBMDMs) were isolated from rat femurs, and subsequent RT‐qPCR and coculture assays were carried out to explore the cellular mechanisms. Immunohistochemical and immunofluorescence staining were used to verify mechanisms in vivo. Results: In vivo results showed that after injection of ASCs, improved texture, increased survival and inhibited contraction of skin grafts were seen. Vascularization was also improved as illustrated by laser perfusion image and vascular endothelial growth factor (VEGF) concentration. Histological analysis revealed that ASCs injection significantly reduced expression of pro‐inflammatory cytokines (TNF‐a, IL‐1β) and increased expression of anti‐inflammatory (IL‐10) and pro‐healing cytokines (IGF‐1). At cellular level, after co‐culturing with rASCs, rat bone marrow derived macrophages (rBMDMs) favored M2 polarization even under inflammatory stimulus. Conclusion: ASCs treatment enhanced vascularization via angiogenic cytokines secretion and alleviated inflammatory environment in skin grafts by driving M2 macrophages polarization, which improved survival and decreased skin grafts contraction. Our work showed that ASCs transplantation can be harnessed to enhance therapeutic efficacy of skin grafting in cutaneous defects treatment. [ABSTRACT FROM AUTHOR]

Aging in a suitable residential environment is essential for the health and well-being of older adults. This study aims to analyze the residential environment preferences (REPs) of older people in China to create a residential environment suitable for their physical and mental health, enhancing their life satisfaction. This study used a sample questionnaire to identify relevant characteristics and analyze preferences, which were validated using non-parametric tests and Pearson's correlation coefficient tests. The questionnaire consisted of 33 questions on characteristics of the residential environment on a 7-point Likert scale and was administered to 433 older adults aged 60 and over in 28 provinces in China. The results showed that "community safety" was the most important environmental characteristic, with an average importance rating of 5.77 out of 6. Accessible building design (average rating of 4.91), emergency response systems (average rating of 4.49), and indoor thermal comfort (average rating of 4.45) were also key factors in promoting aging in place. There was a positive correlation between the community environment and the indoor environment (e.g., community safety and indoor sound insulation, r = 0.209, p < 0.01), and both were, to some extent, negatively correlated with building features (e.g., public toilets and private courtyards, r = −0.278, p < 0.01; indoor thermal comfort and green building design, r = −0.165, p < 0.01). Age and physical health had a strong influence on preferences, but gender had little influence. This study paves the way for future research and policy development on age-friendly housing to ensure sustainable and supportive residential environments for the aging population. [ABSTRACT FROM AUTHOR]