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BackgroundThe physical quantity concerned in the clinical application of 125I particle source brachytherapy is the 1 cm water absorbed dose rate D˙w,1 cm. However, there is no corresponding standard for this physical quantity in China. It is planned to develop an ionization chamber for the absolute measurement of the water absorbed dose rate of the 125I particle source as a standard device, hence the internal electric field of the ionization chamber must first be analyzed to obtain the most reasonable design scheme to satisfy the condition that the electric field intensity is uniformly distributed in the ionization chamber.PurposeThis study aims to simulate the internal electric field of the ionization chamber for the design of particle source water absorbed dose absolute measurement device.MethodsFirstly, the internal model of the ionization chamber was established by Maxwell software to simulate the distribution of electric field intensity under the six variables of the ionization chamber: with or without a protective electrode, different protective electrode ring width, different insulation ring width, different grid number, different grid shape and different grid thickness. Then, qualitative and quantitative analysis were carried out using finite element method. Finally, the influence of different variables on the distribution of electric field intensity in the ionization chamber of the absolute measurement of water absorbed dose of 125I particle source was obtained.ResultsAnalysis results show the ratio of the width of the guard electrode to the radius of the collector electrode must be not less than 2 for design of the ionization chamber. The edge effect at the edge of the collector is increased with width increment of the insulator ring, hence the width of the insulator ring should be reduced as much as possible. When the number of grid electrodes is 15, the variation of the electric field intensity can be reduced to about 1%. When the grid section is rectangular, the variation in electric field intensity is small compared with the circular and triangular grid sections. The larger the thickness of the grid, the more severe the edge effect at the edge of the grid, and the thickness of the grid should be reduced as much as possible.ConclusionsThe uniformity of the electric field can be effectively improved by increasing the number of grid electrodes. Results of this study is helpful to optimal design of the standard device for measuring the absolute water absorbed dose of 125I particle source.

Marek's disease virus (MDV), an alphaherpesvirus, causes severe immunosuppression and T cell lymphomas in chickens, known as Marek's disease (MD), an economically important poultry disease primarily controlled by vaccination. Importantly, it also serves as a comparative model for studying herpesvirus-induced tumor formation in humans. MDV encodes more than 100 genes, most of which have unknown functions. MDV LORF1 is unique to serotype I MDV (MDV-1), lacking homologs in other herpesviruses, and has not been explored yet. To this end, an infectious bacterial artificial chromosome (BAC) harboring the complete genome of the MDV-1 very virulent strain Md5 was generated, and the rescued rMd5 maintained biological properties similar to the parental virus both in vitro and in vivo. Subsequently, rMd5ΔLORF1, a recombinant Md5 virus deficient in pLORF1 expression, was generated by a frameshift mutation in the LORF1 gene. Chickens infected with rMd5ΔLORF1 exhibited a lower mortality rate and delayed bursal atrophy than those infected with the parental rMd5 and the revertant virus (rMd5-reLORF1). Consistently, viral loads of rMd5ΔLORF1 were obviously lower than those of rMd5 or rMd5-reLORF1 in the bursa, but not in the spleen. Importantly, we found that pLORF1 deficiency impairs viral replication in bursal B cells. Furthermore, we showed that pLORF1 associated with the cellular membrane, interacted with MDV structural proteins, and exhibited punctate colocalization with tegument or capsid proteins in the cytoplasm. Taken together, this study demonstrates for the first time that the MDV-1 unique gene LORF1 is involved in MDV-induced bursal atrophy but not in tumor formation. Author summary: Marek's disease virus (MDV) is an extensively studied alphaherpesvirus since it is not only a causative agent of Marek's disease (MD), a highly contagious poultry neoplastic disease posing a significant economic impact on the poultry industry worldwide, but also a comparative model for studying human oncogenic viruses. Although MD has been effectively controlled by massive vaccination since 1969, the continuous emergence of higher virulent strains creates challenges for preventing future outbreaks due to vaccine failure. Therefore, the characterization of unknown genes related to MDV-induced tumor formation and/or immune suppression is of great importance. In this study, we showed for the first time that LORF1, a unique gene of serotype 1 MDV, appears to affect viral replication within the bursa, consequently influencing bursal atrophy. Our findings reveal an essential role of LORF1 in immune suppression, suggesting its potential as a target gene for the development of an MDV gene deletion vaccine. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have gained considerable attention due to their design possibilities as the molecular organic building blocks that can stack in an atomically precise spatial arrangement. Since the inception of COFs in 2005, there has been a continuous expansion in the product range of COFs and their derivatives. This expansion has led to the evolution of three-dimensional structures and various synthetic routes, propelling the field towards large-scale preparation of COFs and their derivatives. This review will offer a holistic analysis and comparison of the spatial structure and synthesis techniques of COFs and their derivatives. The conventional methods of COF synthesis (i.e., ultrasonic chemical, microwave, and solvothermal) are discussed alongside the synthesis strategies of new COFs and their derivatives. Furthermore, the applications of COFs and their derived materials are demonstrated in air, water, and soil pollution management such as gas capture, catalytic conversion, adsorption, and pollutant removal. Finally, this review highlights the current challenges and prospects for large-scale preparation and application of new COFs and the derived materials. In line with the United Nations Sustainable Development Goals (SDGs) and the needs of digital-enabled technologies (AI and machine learning), this review will encompass the future technical trends for COFs in environmental pollution control. [ABSTRACT FROM AUTHOR]

Traditional residences in Southern Jiangsu are residential buildings characterized by local features that embody climate adaptability principles and reflect ecological wisdom and cultural significance rooted in environmental harmony. On the basis of the inheritance of architectural culture and the development of green design, this study aims to explore the scientific and green construction practices of traditional residences, with Xue Fucheng's Former Residence in Wuxi City as a representative case of southern Jiangsu architecture. By measurement and data analysis, this study investigates the indoor thermal environment of traditional residences, focusing on temperature, humidity, wind speed, and radiant heat. It analyzes the methods and architectural mechanisms employed by traditional residences in Southern Jiangsu to control light, wind, and heat in the living environment. The findings summarize the inheritable experience in green and ecological design of traditional residences in Southern Jiangsu, providing a prudent reference for establishing a green building construction model and technique system with distinct features of Southern Jiangsu. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanization, the design of street furniture, as an indispensable part of urban public spaces, faces the challenge of neglecting the user experience. To address this situation, this study adopted a three-level theory of affective design and the Kano model to categorize and rank users' affective needs. The results show that users prefer high-density street furniture that follows traditional urban space design and incorporates elements of traditional Chinese culture and they reject minimalist modern facilities and empty, "hard" plazas. Accordingly, this study proposes emotional design strategies to effectively address the existing problems. Furthermore, this study confirms that the Kano model has significant advantages in identifying the real emotional needs of users, providing data support, and guiding the emotional design of street furniture, which ensures the scientific validity and effectiveness of the design strategy. This study not only deepens the understanding of the emotional design of street facilities but also provides an important reference for future urban space design and planning. [ABSTRACT FROM AUTHOR]

Due to high theoretical capacity and low lithium-storage potential, silicon (Si)-based anode materials are considered as one kind of the most promising options for lithium-ion batteries. However, their practical applications are still limited because of significant volume expansion and poor conductivity during cycling. In this study, we prepared a double core–shell nanostructure through coating commercial Si nanoparticles with both amorphous titanium dioxide (a-TiO2) and amorphous carbon (a-C) via a facile sol–gel method combined with chemical vapor deposition. Elastic behaviors of a-TiO2 shells allowed for the release of strain, maintaining the integrity of Si cores during charge–discharge processes. Additionally, outer layers of a-C provided numerous pore channels facilitating the transport of both Li+ ions and electrons. Using the distribution of relaxation time analysis, we provided a precise kinetic explanation for the observed electrochemical behaviors. Furthermore, the structural evolution of the anode was explored during cycling processes. The Si@a-TiO2@a-C-6 anode was revealed to exhibit excellent electrochemical properties, achieving a capacity retention rate of 86.7% (877.1 mA·h·g−1 after 500 cycles at a 1 A·g−1). This result offers valuable insights for the design of high-performance and cyclically stable Si-based anode materials. [ABSTRACT FROM AUTHOR]

The long-term interplay between rural handicraft industries and village development has resulted in imbalances such as the disorder of living spaces, misalignment of production spaces, and ecological space disruptions. Comprehensively analyzing village landscape elements and actively maintaining their coordinated development are the keys to the transformation of handicraft villages. This study firstly introduces the theory of landscape genes and the concept of "Production–Living–Ecology Spaces" (PLESs) and then constructs the identification system of PLES landscape genes. The system starts from the three dimensions of the production, life, and ecology spaces of the village, identifies the landscape elements that have been passed down from generation to generation, and realizes a comprehensive interpretation of the landscape elements of handicraft villages. Using YaoTou Village in Shaanxi Province as a case study, this study illustrates its landscape characteristics, based on the genetic form of PLES landscape genes, using the G1-FCE method to collect evaluation data from both tourists and residents. These data help to identify the genetic status of the PLES landscape genes of YaoTou Village and propose targeted inheritance mechanisms. The results enable the comprehensive identification of production, ecological, and living landscape elements in handicraft villages, evaluating their inheritance status to carry out targeted modern innovative transformation. This study will provide a reference for identifying and preserving the landscape elements of YaoTou Village and more handicraft villages and contribute to rural revitalization. [ABSTRACT FROM AUTHOR]

The thickness of the inherent filter layer is one of the important performance parameters of the X-ray reference radiation device, and it needs to be quantitatively measured. This research is based on the new version of ISO 4037-1 standard specification, taking N series radiation quality (N-20-N-350) X-ray reference radiation device as an example. Through the PTW30013 ionization chamber, the radiation field under the secondary aperture of different sizes is measured to establish an experimental environment that meets the requirements. The results show that the thickness of the inherent filter layer of the reference radiation device is 0.122 mmAl measured by the half-value layer method; the equivalent inherent filter layer thickness of 4 mm Al under N-40-N-350 radiation quality is obtained by increasing the thickness of the aluminum filter. Using the conversion relationship between the mass-energy absorption coefficient of elemental aluminum metal and beryllium metal at different energies, the equivalent intrinsic filter layer thickness of 1 mm Be under N-20-N-30 radiation quality is obtained. This study provides a certain reference for the measurement of the inherent filtering of the X-ray reference radiation device.

Simple Summary: The tea green leafhopper, Empoasca flavescens Fabrecius, is the most notorious pest in Chinese tea plantations, predominantly controlled through pesticide applications for decades. Recognizing the pressing need for novel, effective, and eco-friendly strategies to manage leafhoppers, this study aims to contribute to the reduction in pesticide usage in the tea industry. Salivary protein research is pivotal for gaining insights into effectors or elicitors, facilitating the exploration of novel regulatory targets and pathways in tea green leafhoppers. In this study, saliva from adult tea green leafhoppers was collected using a self-made collection device equipped with two layers of Parafilm stretched over a sucrose diet. Following freeze drying and filter-aided sample preparation (FASP), liquid chromatography–tandem mass spectrometry (LC-MS/MS) was employed to analyze the saliva proteins. Bioinformatics methodologies were then leveraged to predict the secretory proteins. The results suggest that the interactions between leafhoppers and tea plants, particularly in terms of feeding and defense responses, may be mediated by elicitors or effectors, such as mucin-like protein (EfMucin), vitellogenin (EfVg), odorant-binding protein (EfOBP), and others. The conclusive outcomes of this study provide new insights into the coevolutionary dynamics between tea plants and leafhoppers, offering novel pathways for the development of advanced leafhopper control technologies. Saliva plays a crucial role in shaping the compatibility of piercing–sucking insects with their host plants. Understanding the complex composition of leafhopper saliva is important for developing effective and eco-friendly control strategies for the tea green leafhopper, Empoasca flavescens Fabrecius, a major piercing–sucking pest in Chinese tea plantations. This study explored the saliva proteins of tea green leafhopper adults using a custom collection device, consisting of two layers of Parafilm stretched over a sucrose diet. A total of 152 proteins were identified using liquid chromatography–tandem mass spectrometry (LC-MS/MS) following the filter-aided sample preparation (FASP). These proteins were categorized into six groups based on their functions, including enzymes, transport proteins, regulatory proteins, cell structure proteins, other proteins, and unknown proteins. Bioinformatics analyses predicted 16 secreted proteins, which were successfully cloned and transcriptionally analyzed across various tissues and developmental stages. Genes encoding putative salivary secretory proteins, including Efmucin1, EfOBP1, EfOBP2, EfOBP3, Efmucin2, low-density lipoprotein receptor-related protein (EfLRP), EFVg1, and EFVg2, exhibited high expressions in salivary gland (SG) tissues and feeding-associated expressions at different developmental stages. These findings shed light on the potential elicitors or effectors mediating the leafhopper feeding and defense responses in tea plants, providing insights into the coevolution of tea plants and leafhoppers. The study's conclusions open avenues for the development of innovative leafhopper control technologies that reduce the reliance on pesticides in the tea industry. [ABSTRACT FROM AUTHOR]

To investigate the effect of stemming length on the blasting of cylindrical rock samples, a three-dimensional zone-divided model of cylindrical rock samples undergoing single-hole charging was established through numerical simulation methods. A comparative analysis was conducted on the damage, displacement, and crack propagation of the stemming and rock by changing the stemming lengths. The simulation results were consistent with the observed crack propagation and damage during the blasting process of the cylindrical rock samples in the laboratory, validating the effectiveness of the blasting model in simulating the rock blasting process. Within a stemming length that constitutes 23.7% of the borehole length, an increase in stemming length considerably suppresses the extent of stemming expulsion from the borehole and the unit inhibition effect diminishes beyond this range. As stemming length increases from 7.9% to 39.5% of the borehole length, the complexity of surface crack networks gradually decreases while crack width significantly increases. The highest damage value, reaching 0.75, occurs in the middle region of the rock pillar at a stemming length of 23.7% of the borehole length. In the upper region of the rock pillar, the damage shows a concave change with the stemming length, with a difference of 0.054 3. Among the five stemming lengths, the largest difference in damage is observed in the middle region of the rock pillar, with a value of 0.067 9. The impact of the damage in the lower region of the rock pillar is relatively small, with a variation amplitude of 0.009 9. The reasonable selection of stemming length offers a new approach to achieving precise regional blasting and improving blasting effectiveness. [ABSTRACT FROM AUTHOR]

Objective. Multi-contrast magnetic resonance (MR) imaging super-resolution (SR) reconstruction is an effective solution for acquiring high-resolution MR images. It utilizes anatomical information from auxiliary contrast images to improve the quality of the target contrast images. However, existing studies have simply explored the relationships between auxiliary contrast and target contrast images but did not fully consider different anatomical information contained in multi-contrast images, resulting in texture details and artifacts unrelated to the target contrast images. Approach. To address these issues, we propose a dual contrast attention-guided multi-frequency fusion (DCAMF) network to reconstruct SR MR images from low-resolution MR images, which adaptively captures relevant anatomical information and processes the texture details and low-frequency information from multi-contrast images in parallel. Specifically, after the feature extraction, a feature selection module based on a dual contrast attention mechanism is proposed to focus on the texture details of the auxiliary contrast images and the low-frequency features of the target contrast images. Then, based on the characteristics of the selected features, a high- and low-frequency fusion decoder is constructed to fuse these features. In addition, a texture-enhancing module is embedded in the high-frequency fusion decoder, to highlight and refine the texture details of the auxiliary contrast and target contrast images. Finally, the high- and low-frequency fusion process is constrained by integrating a deeply-supervised mechanism into the DCAMF network. Main results. The experimental results show that the DCAMF outperforms other state-of-the-art methods. The peak signal-to-noise ratio and structural similarity of DCAMF are 39.02 dB and 0.9771 on the IXI dataset and 37.59 dB and 0.9770 on the BraTS2018 dataset, respectively. The image recovery is further validated in segmentation tasks. Significance. Our proposed SR model can enhance the quality of MR images. The results of the SR study provide a reliable basis for clinical diagnosis and subsequent image-guided treatment. [ABSTRACT FROM AUTHOR]