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In this paper, it is proved that there is a positive proportion of positive odd integers which can be uniquely represented as p + 2a2 + 2b2, where p is a prime and a,b are two positive integers with a ≤ b. [ABSTRACT FROM AUTHOR]

Background: A dosimeter with high spatial and temporal resolution would be of significant interest for pencil beam scanning (PBS) proton beams' characterization, especially when facing small fields and beams with high temporal dynamics. Optical imaging of scintillators has potential in providing sub‐millimeter spatial resolution with pulse‐by‐pulse basis temporal resolution when the imaging system is capable of operating in synchrony with the beam‐producing accelerator. Purpose: We demonstrate the feasibility of imaging PBS proton beams as they pass through a plastic scintillator detector to simultaneously obtain multiple beam parameters, including proton range, pencil beam's widths at different depths, spot's size, and spot's position on a pulse‐by‐pulse basis with sub‐millimeter resolution. Materials and methods: A PBS synchrocyclotron was used for proton irradiation. A BC‐408 plastic scintillator block with 30 × 30 × 5 cm3 size, and another block with 30 × 30 × 0.5 cm3 size, positioned in an optically sealed housing, were used sequentially to measure the proton range, and spot size/location, respectively. A high‐speed complementary metal‐oxide‐semiconductor (CMOS) camera system synchronized with the accelerator's pulses through a gating module was used for imaging. Scintillation images, captured with the camera directly facing the 5‐cm‐thick scintillator, were corrected for background (BG), and ionization quenching of the scintillator to obtain the proton range. Spots' position and size were obtained from scintillation images of the 0.5‐cm‐thick scintillator when a 45° mirror was used to reflect the scintillation light toward the camera. Results: Scintillation images with 0.16 mm/pixel resolution corresponding to all proton pulses were captured. Pulse‐by‐pulse analysis showed that variations of the range, spots' position, and size were within ± 0.2% standard deviation of their average values. The absolute ranges were within ± 1 mm of their expected values. The average spot‐positions were mostly within ± 0.8 mm and spots' sigma agreed within 0.2 mm of the expected values. Conclusion: Scintillation‐imaging PBS beams with high‐spatiotemporal resolution is feasible and may help in efficient and cost‐effective acceptance testing and commissioning of existing and even emerging technologies such as FLASH, grid, mini‐beams, and so forth. [ABSTRACT FROM AUTHOR]

Given a graph G and an edge $ e\in E(G) $ e ∈ E (G) , let S be a vertex set of G. For any two vertices x, $ y\in S $ y ∈ S , if e belongs to all the shortest paths between x and y, then x and y can monitor the edge e. For each edge e of G, if there exists x and y in S such that x and y can monitor e, then the set S can be called a monitoring-edge-geodetic ( $ \operatorname {MEG} $ MEG for short) set of G. The $ \operatorname {MEG} $ MEG number, denoted by $ \operatorname {meg}(G) $ meg ⁡ (G) , is the size of the smallest $ \operatorname {MEG} $ MEG set of G. In this paper, we obtain the exact values of the $ \operatorname {MEG} $ MEG numbers for radix triangular mesh networks, Sierpiński graphs, Sierpiński gasket graphs and Sierpiński generalized graphs. [ABSTRACT FROM AUTHOR]

For a set M of vertices and an edge e of a graph G, let $ P_G(M, e) $ P G (M , e) be the set of the pair $ (x, y) $ (x , y) with a vertex x of M and a vertex y of $ V(G) $ V (G) such that $ d_G(x, y)\neq d_{G-e}(x, y) $ d G (x , y) ≠ d G − e (x , y). For a vertex x, let $ EM(x) $ EM (x) be the edge set e such that there exists a vertex v in G with $ (x, v) \in P(\{x\}, e) $ (x , v) ∈ P ({ x } , e). A set M of vertices of a graph G is distance-edge-monitoring set if every edge e of G is monitored by some vertex $ v\in M $ v ∈ M , that is, for any $ e \in E(G) $ e ∈ E (G) , we have $ P_G(M, e)\neq \emptyset $ P G (M , e) ≠ ∅. The distance-edge-monitoring number of a graph G, denoted by $ \operatorname {dem}(G) $ dem ⁡ (G) , is defined as the smallest size of distance-edge-monitoring sets of G. In this paper, we study the distance edge monitoring number of pseudo wheel graphs, that is, some variants of wheel graph. [ABSTRACT FROM AUTHOR]

Design of flexible porous materials where the diffusion of guest molecules is regulated by the dynamics of contracted pore aperture is challenging. Here, a flexible porous self‐assembly consisting of 1D channels with dynamic bottleneck gates is reported. The dynamic pendant naphthimidazolylmethyl moieties at the channel necks provide kinetic gate function, that enables unusual adsorption for light hydrocarbons. The adsorption for CO2 is mainly dominated by thermodynamics with the uptakes decreasing with increasing temperature, whereas the adsorptions for larger hydrocarbons are controlled by both thermodynamics and kinetics resulting in an uptake maximum at a temperature threshold. Such an unusual adsorption enables temperature‐dependent separation of CO2 from the corresponding hydrocarbons. [ABSTRACT FROM AUTHOR]

Florida Bay, a large and shallow estuary, serves as a vital habitat for a diverse range of marine species and holds significant environmental, commercial, and recreational value. The Florida Bay ecosystem is under extensive stress due to decades of increased nutrient loads. Based on the Environmental Fluid Dynamics Code (EFDC), a hydrodynamic model was developed in this study. The model was calibrated with a comprehensive dataset, including measurements over 7 years from 34 tidal stations, 42 current stations, and 14 temperature and salinity stations. Key findings include the following: (1) the bay exhibits a shift in the tidal regime, transitioning from macro-tidal in the western region to micro-tidal in the central and eastern/northeast regions; (2) local winds and the subtidal variations from the coastal ocean are the primary drivers for the hydrodynamic processes in the eastern and central regions; (3) salinity changes in the bay are primarily controlled by three processes: the net supply of freshwater, the processes that drive mixing within the estuary (e.g., wind, topography, currents), and the exchange of salinity with the coastal ocean. This hydrodynamic model is essential for providing a comprehensive tool to address environmental challenges and sustain the bay's ecosystem health. [ABSTRACT FROM AUTHOR]

The chalcopyrite compound CuGa(In)Te2 has garnered significant attention due to its safe elemental composition and high thermoelectric potential. Optimizing the carrier concentration and reducing the lattice thermal conductivity of CuGa(In)Te2 can significantly enhance its thermoelectric performance. In this mini-review, we analyze the electronic and phonon structures of CuGa(In)Te2, summarize and categorize the representative methods employed in recent years to improve its thermoelectric performance. Our analysis reveals that reducing thermal conductivity has a more significant impact on enhancing the ZT value of CuGa(In)Te2 compared to increasing the power factor. In conclusion, we outline potential challenges and provide a brief outlook, offering valuable insights into the design of CuGa(In)Te2 chalcopyrite compounds as high-performance thermoelectric materials. [ABSTRACT FROM AUTHOR]

Improving the positioning accuracy of underground personnel can not only strengthen mine safety monitoring, but also increase the speed of rescue, thus ensuring the life safety of underground personnel to the maximum extent.This paper proposes a positioning model based on IPSO-LSTM for position prediction of underground moving targets in response to the problem of existing ranging algorithms which are affected by the on-site environment, resulting in insufficient positioning accuracy.This article uses LSTM to build a fingerprint positioning model.It collects distance information through the UWB wireless module to build a distance-position fingerprint relationship database, which is used to train the PSO-LSTM model.Then we use the trained model to predict target trajectories.We compared four improvement strategies on PSO including random initialization of population position by chaotic mapping, nonlinear inertia weight reduction and fitness function optimization.Experiments show that the improved PSO optimization algorithm in this paper exhibit fast convergence speed and good robustness.In order to verify the positioning effect of IPSO-LSTM, we compared the IPSO-LSTM model with the Chan algorithm, PSO-LSTM model, LSTM neural network, SSA-LSTM model and GWO-LSTM.The average positioning error is used as the evaluation index.The results show that the average positioning error of the IPSO-LSTM positioning model proposed in this study is 30mm, which is 76% higher than the traditional Chan algorithm, 49% higher than the LSTM, and 24% higher than the PSO-LSTM model.In order to reduce large local errors, we used median filtering to process input information, further improving positioning accuracy.This study offers references for improving the accuracy and stability of the existing underground moving target positioning system.

Abstract Background Research has suggested significant correlations among ageing, immune microenvironment, inflammation and tumours. However, the relationships among ageing, immune microenvironment, cystitis and bladder urothelial carcinoma (BLCA) in the bladder have rarely been reported. Methods Bladder single-cell and transcriptomic data from young and old mice were used for immune landscape analysis. Transcriptome, single-cell and The Cancer Genome Atlas Program datasets of BLCA and interstitial cystitis/bladder pain syndrome (IC/BPS) were used to analyse immune cell infiltration and molecular expression. Bladder tissues from mice, IC/BPS and BLCA were collected to validate the results. Results Eight types of immune cells (macrophages, B-cells, dendritic cells, T-cells, monocytes, natural killer cells, γδ T-cells and ILC2) were identified in the bladder of mice. Aged mice bladder tissues had a significantly higher number of T-cells, γδ T-cells, ILC2 and B-cells than those in the young group (P

ObjectiveThis study aimed to design a low-cost, simulation training platform for the ligation of deep dorsal vein (DVC) complex in radical prostatectomy and validate its training effectiveness.MethodsA simplified prostate urethra model was produced by 0-degree silica gel and pulse pressure banding. This model was placed on a slope of about 30 degrees using cardboard to thus creating a narrow environment of the pelvis. The DVC ligation was performed by a 2D laparoscopy simulator. A total of 27 participants completed the study include 13 novices, 10 surgical residents and 4 urology experts. The novices were trained five trails with 24 hours interval, the residents and experts completed the DVC ligation once. The construct validity of this simulation training platform was performed by completing time, the GOALS (Global Operative Assessment of Laparoscopic Skills) and TSA (i.e. Task Specific Assessments) score. The face validity and content validity were performed by a specific closed-ended questionnaire.ResultsThere was no significant difference among three groups in demographic or psychometric variables (p > 0.05). Compared to the novices, the residents spend a shorter time to complete the DVC ligation (p < 0.05) and had higher GOALS scores (p < 0.05), but had no significant difference in TSA scores (p > 0.05). Additionally, the experts groups had a better performance compared to residents group in the completing time (p < 0.05), GOALS score (p < 0.05) and TSA score (p < 0.05). The learning curve of novices significantly promoted along with the increased times of training. Almost 90 percent of subjects considered that this simulator had a good performance in the realism and practicability.ConclusionWe developed a novel low-cost a simulation training platform for the ligation of deep dorsal vein complex in radical prostatectomy, and this simulator had a good performance in the construct validity, face validity and content validity.

Intratumoral microbiota has become research hotspots, and emerges as a non-negligent new component of tumor microenvironments (TME), due to its powerful influence on tumor initiation, metastasis, immunosurveillance and prognosis despite in low-biomass. The accumulations of microbes, and their related components and metabolites within tumor tissues, endow TME with additional pluralistic features which are distinct from the conventional one. Therefore, it's definitely necessary to comprehensively delineate the sophisticated landscapes of tumor microbe microenvironment, as well as their functions and related underlying mechanisms. Herein, in this review, we focused on the fields of tumor microbe microenvironment, including the heterogeneity of intratumor microbiota in different types of tumors, the controversial roles of intratumoral microbiota, the basic features of tumor microbe microenvironment (i.e., pathogen-associated molecular patterns (PAMPs), typical microbial metabolites, autophagy, inflammation, multi-faceted immunomodulation and chemoresistance), as well as the multidisciplinary approach-based intervention of tumor microbiome for cancer therapy by applying wild-type or engineered live microbes, microbiota metabolites, antibiotics, synthetic biology and rationally designed biomaterials. We hope our work will provide valuable insight to deeply understand the interplay of cancer-immune-microbial, and facilitate the development of microbes-based tumor-specific treatments.

Tumors pose a significant global public health challenge, resulting in numerous fatalities annually. CD8+ T cells play a crucial role in combating tumors; however, their effectiveness is compromised by the tumor itself and the tumor microenvironment (TME), resulting in reduced efficacy of immunotherapy. In this dynamic interplay, extracellular vesicles (EVs) have emerged as pivotal mediators, facilitating direct and indirect communication between tumors and CD8+ T cells. In this article, we provide an overview of how tumor-derived EVs directly regulate CD8+ T cell function by carrying bioactive molecules they carry internally and on their surface. Simultaneously, these EVs modulate the TME, indirectly influencing the efficiency of CD8+ T cell responses. Furthermore, EVs derived from CD8+ T cells exhibit a dual role: they promote tumor immune evasion while also enhancing antitumor activity. Finally, we briefly discuss current prevailing approaches that utilize functionalized EVs based on tumor-targeted therapy and tumor immunotherapy. These approaches aim to present novel perspectives for EV-based tumor treatment strategies, demonstrating potential for advancements in the field.

Abstract Refractory diabetic wounds are associated with high incidence, mortality, and recurrence rates and are a devastating and rapidly growing clinical problem. However, treating these wounds is difficult owing to uncontrolled inflammatory microenvironments and defective angiogenesis in the affected areas, with no established effective treatment to the best of our knowledge. Herein, we optimized a dual functional therapeutic agent based on the assembly of LL‐37 peptides and diblock copolymer poly(ethylene glycol)–poly(propylene sulfide) (PEG–PPS). The incorporation of PEG–PPS enabled responsive or controlled LL‐37 peptide release in the presence of reactive oxygen species (ROS). LL‐37@PEG–PPS nanomicelles not only scavenged excessive ROS to improve the microenvironment for angiogenesis but also released LL‐37 peptides and protected them from degradation, thereby robustly increasing angiogenesis. Diabetic wounds treated with LL‐37@PEG–PPS exhibited accelerated and high‐quality wound healing in vivo. This study shows that LL‐37@PEG–PPS can restore beneficial angiogenesis in the wound microenvironment by continuously providing angiogenesis‐promoting signals. Thus, it may be a promising drug for improving chronic refractory wound healing.

BackgroundAutism spectrum disorder (ASD) is associated with alterations in the gut microbiome. However, there are few studies on gut microbiota of children with ASD in China, and there is a lack of consensus on the changes of bacterial species.PurposeAutism spectrum disorder (ASD) is associated with alterations in the gut microbiome. However, there are few studies on gut microbiota of children with ASD in China, and there is a lack of consensus on the changes of bacterial species.MethodsWe used 16S rRNA sequencing to analyze ASD children (2 to 12 years), HC (2 to 12 years).ResultsOur findings showed that the α-diversity, composition, and relative abundance of gut microbiota in the ASD group were significantly different from those in the HC groups. Compared with the HC group, the α-diversity in the ASD group was significantly decreased. At the genus level, the relative abundance of g_Faecalibacterium, g_Blautia, g_Eubacterium_eligens_group, g_Parasutterella, g_Lachnospiraceae_NK4A136_group and g_Veillonella in ASD group was significantly increased than that in HC groups, while the relative abundance of g_Prevotella 9 and g_Agathobacter was significantly decreased than that in HC groups. In addition, KEGG pathway analysis showed that the microbial functional abnormalities in ASD patients were mainly concentrated in metabolic pathways related to fatty acid, amino acid metabolism and aromatic compound metabolism, and were partially involved in neurotransmitter metabolism.ConclusionThis study revealed the characteristics of gut microbiota of Chinese children with ASD and provided further evidence of gut microbial dysbiosis in ASD.

In the context of carbon neutrality and urbanization, there is a notable research gap regarding the carbon sequestration benefits of urban forests and the identification of suitable tree species for achieving sustainable carbon sequestration. In this study, we examined the dynamics and drivers of urban forest carbon sequestration in Shanghai, one of the most urbanized cities in China. First, we compiled a comprehensive field inventory data set spanning 20 years for the Shanghai Green Belt. Second, we quantified and compared the total carbon accumulation and growth rates of six monoculture forests and two mixed forest types consisting of six common tree species. Third, we conducted drivers analysis of the effects of stand-related and anthropogenic factors on carbon accumulation and growth rates. Overall, our results revealed that each forest type exhibited a unique growth pattern of tree biomass carbon (TBC), with the Chapman–Richards growth function providing an accurate representation of carbon dynamics. During the early stages of development (within 20 years), the carbon accumulation rate of Populus L. reached 4.13 Mg ha−1 yr−1, which was approximately 127 % higher than that of broadleaf mixed forests. In late stages, the potential tree biomass carbon accumulation of broadleaf mixed forests reached 172.8 Mg ha−1, which was 34 % higher than that of Populus L. over the entire growth cycle. Forest types, stand age, canopy density class, ownership, closure management, strongly influence the accumulation rates of TBC. Overall, these findings contribute to the understanding of the advantages of mixed and monoculture plantations for carbon sequestration, and these results can be used to predict future patterns of carbon storage in urban forests in Shanghai.

The three-dimensional frequency-domain linearized Navier-Stokes equations (LNSEs) with consideration of eddy viscosity are developed to evaluate the acoustic attenuation performance of perforated hybrid mufflers in the presence of non-uniform flow. The computations are performed in two steps: time averaged flow variables are acquired by using steady-state computational fluid dynamics (CFD) method and then mapped into the acoustic mesh, and the acoustic perturbation variables are obtained by solving frequency-domain LNSEs, where the sound-absorbing material is treated as an equivalent fluid with complex sound speed and density. The predictions of transmission losses of the two-pass perforated hybrid mufflers in the presence of non-uniform flow are in good consistencies with the measurements, which verifies the correctness of LNSEs. The effect of Mach numbers on acoustic attenuation performance of the mufflers with different filling densities and perforated components is investigated in detail. The transmission loss of the mufflers with various filling densities are increased by complex airflow in the lower frequency range. For the mufflers where not all components have been perforated, the flow lowers low-frequency resonance peak. The influence of complex airflow on acoustic attenuation performance of all configurations is weakened at higher frequencies.