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Classical diffusion model-based image registration approaches require separate diffusion and deformation networks to learn the reverse Gaussian transitions and predict deformations between paired images, respectively. However, such cascaded architectures introduce noisy inputs in the registration, leading to excessive computational complexity and issues with low registration accuracy. To overcome these limitations, a diffusion model-based universal network for image registration and generation (UNIRG) is proposed. Specifically, the training process of the diffusion model is generalized as a process of matching the posterior mean of the forward process to the modified mean. Subsequently, the equivalence between the training process for image generation and that for image registration is verified by incorporating the deformation information of the paired images to obtain the modified mean. In this manner, UNIRG integrates image registration and generation within a unified network, achieving shared training parameters. Experimental results on 2D facial and 3D cardiac medical images demonstrate that the proposed approach integrates the capabilities of image registration and guided image generation. Meanwhile, UNIRG achieves registration performance with NMSE of 0.0049, SSIM of 0.859, and PSNR of 27.28 on the 2D facial dataset, along with Dice of 0.795 and PSNR of 12.05 on the 3D cardiac dataset.

Accurate segmentation of the pulmonary airway tree is crucial for diagnosing lung diseases. To tackle the issues of low segmentation accuracy and frequent leaks in existing methods, this paper proposes a precise segmentation method using quasi-spherical region-constrained wavefront propagation with tracheal wall gap sealing. Based on the characteristic that the surface formed by seed points approximates the airway cross-section, the width of the unsegmented airway is calculated, determining the initial quasi-spherical constraint region. Using the wavefront propagation method, seed points are continuously propagated and segmented along the tracheal wall within the quasi-spherical constraint region, thus overcoming the need to determine complex segmentation directions. To seal tracheal wall gaps, a morphological closing operation is utilized to extract the characteristics of small holes and locate low-brightness tracheal wall gaps. By filling the CT values at these gaps, the method seals the tracheal wall gaps. Extensive experiments on the EXACT09 dataset demonstrate that our algorithm ranks third in segmentation completeness. Moreover, its performance in preventing airway leaks is significantly better than the top-two algorithms, effectively preventing large-scale leak-induced spread.

Insecticide exposure may affect childhood asthma/wheezing, but evidence is scarce in low- and middle-income countries. We conducted a population-based cross-sectional study in Sanya, China. Generalized linear models were adopted to assess the associations of insecticide exposure with childhood asthma/wheezing, reported as odds ratios (ORs) and 95% confidence intervals (CIs). A subgroup analysis was performed to explore the possible effects of sociodemographic and environmental factors on these associations. The median age of the 9754 children was 6.7 years, and 5345 (54.8%) were boys. The prevalences of ever asthma (EA), ever wheezing (EW), and current wheezing (CW) were 7.4%, 5.3%, and 2.9%, respectively. We found a greater prevalence of childhood EA with insecticide exposure (OR = 1.18, 95% CI: 1.00, 1.38). Outdoor insecticide exposure was associated with elevated ORs for EA (1.24, 95% CI: 1.03, 1.50), EW (1.27, 95% CI: 1.03, 1.57), and CW (1.38, 95% CI: 1.04, 1.81). The p for the trend in insecticide exposure frequency was significant for EA (p = 0.001) and CW (p = 0.034). These adverse impacts were pronounced in girls who were exposed to low temperatures. Our findings suggest adverse effects of insecticide use, especially outdoors, on childhood asthma/wheezing. Further studies are warranted to verify this association and develop tailored prevention measures.

The benefits of variable speed centrifugal pumps include high stability, a broad operating range, and adjustable input power. In water distribution systems, the pump units are increasingly using variable speed technology. The energy-saving features and operational stability of the pump station are directly impacted by the hydraulic performance and the operation strategy. In this study, CFD numerical analysis and model tests were adopted to design and evaluate the hydraulic performance of the variable speed centrifugal pump with large flow and wide head variation in Liyuzhou Pump Station. Under the premise of ensuring the wide head variation, the optimized centrifugal pump met the requirements of hump margin and efficiency in the high head zone and the cavitation margin in the low head zone. The test results demonstrated that the operational range of the variable speed centrifugal pump was successfully widened by reasonable hydraulic parameters selection and impeller optimization. The safe and efficient operational range of the variable speed unit was determined by means of taking the performance requirements of the pump’s maximum input shaft power, cavitation characteristics and pressure fluctuation into consideration. The scientific and reasonable operational path to meet the various operation needs was also investigated and determined for the pump station’s actual operation needs. A high efficiency, safe operation, and a simplified control logic were achieved by using the operational path, which makes it a reasonable potential guide for hydraulic design and operational optimization of variable speed centrifugal pumps with large flow and wide head range.

Dietary polyphenols are reported to alleviate colitis by interacting with gut microbiota which plays an important role in maintaining the integrity of the intestinal barrier. As a type of dietary polyphenol, whether ligustroside (Lig) could alleviate colitis has not been explored yet. Here, we aimed to determine if supplementation of ligustroside could improve colitis. We explored the influence of ligustroside intake with different dosages on colitis induced with dextran sulfate sodium (DSS). Compared to the DSS group, supplementation of ligustroside could reduce body weight (BW) loss, decrease disease activity indices (DAI), and relieve colon damage in colitis mice. Furthermore, ligustroside intake with 2 mg/kg could decrease proinflammatory cytokine concentrations in serum and increase immunoglobulin content and antioxidant enzymes in colon tissue. In addition, supplementation of ligustroside (2 mg/kg) could reduce mucus secretion and prevent cell apoptosis. Also, changes were revealed in the bacterial community composition, microbiota functional profiles, and intestinal metabolite composition following ligustroside supplementation with 2 mg/kg using 16S rRNA sequencing and non-targeted lipidomics analysis. In conclusion, the results showed that ligustroside was very effective in preventing colitis through reduction in inflammation and the enhancement of the intestinal barrier. Furthermore, supplementation with ligustroside altered the gut microbiota and lipid composition of colitis mice.

Aiming at the current complex problem of the mechanized high-quality picking of tender tea buds, this paper designs a tender tea bud-picking manipulator. In the picking process, the quality of the petiole and leaf blade of the tender tea bud is crucial, as the traditional cutting picking method destroys the cell structure of the tender tea buds, resulting in rapid oxidation of the cuts, thus losing the bright green appearance and pure taste. For this reason, this paper draws on the quality requirements of tender tea buds and traditional manual picking technology, simulating the process of the manual picking action, putting forward a ‘rotary pull-up’ clamping and ripping picking method, and designing the corresponding actuating structure. Using PVDF material piezoelectric thin-film sensors to detect the clamping force of the tender tea bud picking, the corresponding sensor hardware circuit is designed. In addition, the finite element analysis method is also used to carry out stress analysis on the mechanical fingers to verify the rationality of the automatic mechanism to ensure the high-quality picking of tender tea buds. In terms of the control of the manipulator, an SMC-PID control method is designed by using MATLAB/Simulink 2021 and Adam 2020 software for joint simulation. The way to control the closed-loop system angle and angular velocity error feedback is by adjusting the PID parameters, which quickly converts the sliding mode control to the sliding mode surface. The simulation results show that the SMC-PID control method proposed in this paper can meet the demand in tender tea bud picking and simultaneously has high control accuracy, response speed, and stability.

Underground coal mining will inevitably cause serious ground deformation, and therefore, preventive mining-induced deformation analysis (MIDA) is of great importance in assisting mining planning and decision-making. Current web-based Geographic Information System (webGIS)-based applications usually use 2D GIS data and lack a holistic framework. This study presents a multi-scalar oblique photogrammetry-supported unified 3D webGIS framework for MIDA applications to fill this gap. The developed web platform uses multiple open-source JavaScript libraries, and the prototype system provides user-friendly interfaces for GIS data collecting and corresponding database establishment, geo-visualization and query, dynamic prediction, and spatial overlapping analysis within the same framework. The proposed framework was tested and evaluated in the Qianyingzi mining area in eastern China. The results demonstrated that multi-scalar oblique photogrammetry balances data quality and acquisition efficiency and provides a good source of GIS datasets, and the web-based platform has a good absolute and relative spatial accuracy verified by two types of validation data. Practical application results proved the feasibility and reliability of the system. The developed web-based MIDA prototype system attains an appealing performance and can be easily extended to similar geoscience applications.

GSK2606414 is a new, effective, highly selective PERK inhibitor with adenosine-triphosphate-competitive characteristics. It can inhibit endoplasmic reticulum stress and has the possibility of treating periodontitis. However, owing to its strong hydrophobicity and side effects, highly efficient pharmaceutical formulations are urgently needed to improve the bioavailability and therapeutic efficacy of GSK2606414 in the treatment of periodontitis. Herein, a novel local GSK2606414 delivery system was developed by synthesizing GSK2606414 nanoparticles (NanoGSK) and further loading NanoGSK into a collagenase-responsive hydrogel. The drug release results showed that the drug-loaded hydrogels had outstanding enzymatic responsive drug release profiles under the local microenvironment of periodontitis. Furthermore, in vitro studies showed that the drug-loaded hydrogel exhibited good cellular uptake and did not affect the growth and proliferation of normal cells, while the drug-loaded hydrogel significantly improved the osteogenic differentiation of inflammatory cells. In the evaluations of periodontal tissue repair, the drug-loaded hydrogels showed a great effect on inflammation inhibition, as well as alveolar bone regeneration. Therefore, this work introduces a promising strategy for the clinical treatment of periodontitis.

The luminous environment is an essential factor that affects people’s working and living experiences in buildings. In order to clarify the building luminous environment parameters that are required for occupant satisfaction, we collected 2553 completed questionnaires while conducting field measurements of new and updated luminous comfort metrics in 15 contexts in four cities in China. By developing a five-step approach to identifying the luminous environment needs of different building occupants, including data cleaning, correlation analysis, and nonparametric testing, we determined the thresholds for all key metrics for each scenario. The research results show that different public building environments have unique luminous environment improvement requirements, and this conclusion can guide future lighting design, LED technology and daylighting integration technology.

Fungal pathogens of the Cryptococcus neoformans species complex (C. neoformans SC) are a major cause of fungal meningitis in immunocompromised individuals. As with other melanotic microorganisms associated with human diseases, the cell-wall-associated melanin of C. neoformans SC is a major virulence factor that contributes to its ability to evade host immune responses. The levels of melanin substrate and the regulation of melanin formation could be influenced by the microbiota–gut–brain axis. Moreover, recent studies show that C. neoformans infections cause dysbiosis in the human gut microbiome. In this review, we discuss the potential association between cryptococcal meningitis and the gut microbiome. Additionally, the significant potential of targeting the gut microbiome in the diagnosis and treatment of this debilitating disease is emphasized.

Laser powder bed fusion (LPBF) is a typical additive manufacturing technology that offers significant advantages in the production of complex components. With the rapid heating and cooling characteristics of LPBF, a large amount of solid solution of alloying elements in the matrix can be achieved to form supersaturated solid solutions, thus enhancing the properties of LPBF alloys. For the unique microstructure, the heat treatment process needs to be adjusted accordingly. In this work, a Zr/Sc-modified Al-Mg alloy processed by laser powder bed fusion (LPBF) with relatively low cost and good mechanical properties was investigated. The fine microstructure was obtained under rapid solidification conditions. The nanoscale Al3(Sc,Zr) particles precipitated at the molten pool boundary during solidification. These particles, as effective heterogeneous nucleators, further refined the α-Al grains and improved the mechanical properties of the alloy. As a result, the alloy exhibited a heterogeneous microstructure consisting of columnar grains in the center of the molten pool and equiaxed grains at the boundaries. The rapid solidification resulted in the supersaturation of solute atoms in the α-Al matrix, which significantly enhanced the solid solution strengthening effect. With the LPBF processing parameters of a combination of a laser power of 250 W, a laser scanning speed of 833 mm/s, and stripe scanning mode, the tensile strength of the alloy reached 401.4 ± 5.7 MPa, which was significantly higher than that of the cast alloys with aging treatment (281.1 ± 1.3 MPa). The heat treatment promoted the formation of secondary Al3(Sc,Zr), Mn/Mg-rich phases. The ultimate tensile strength and elongation at fracture after aging at 325 °C for 2 h were 536.0 ± 1.7 MPa and 14.8 ± 0.8%, respectively. The results provide insight into the preparation of aluminum alloys with relatively low cost and excellent mechanical properties.

The recognition of environmental patterns for traditional Chinese settlements (TCSs) is a crucial task for rural planning. Traditionally, this task primarily relies on manual operations, which are inefficient and time consuming. In this paper, we study the use of deep learning techniques to achieve automatic recognition of environmental patterns in TCSs based on environmental features learned from remote sensing images and digital elevation models. Specifically, due to the lack of available datasets, a new TCS dataset was created featuring five representative environmental patterns. We also use several representative CNNs to benchmark the new dataset, finding that overfitting and geographical discrepancies largely contribute to low classification performance. Consequently, we employ a semantic segmentation model to extract the dominant elements of the input data, utilizing a metric-based meta-learning method to enable the few-shot recognition of TCS samples in new areas by comparing their similarities. Extensive experiments on the newly created dataset validate the effectiveness of our proposed method, indicating a significant improvement in the generalization ability and performance of the baselines. In sum, the proposed method can automatically recognize TCS samples in new areas, providing a powerful and reliable tool for environmental pattern research in TCSs.

Background: Colposcopy plays an essential role in cervical cancer control, but its performance remains unsatisfactory. This study evaluates the feasibility of machine learning (ML) models for predicting high-grade squamous intraepithelial lesions or worse (HSIL+) in patients referred for colposcopy by combining colposcopic findings with demographic and screening results. Methods: In total, 7485 patients who underwent colposcopy examination in seven hospitals in mainland China were used to train, internally validate, and externally validate six commonly used ML models, including logistic regression, decision tree, naïve bayes, support vector machine, random forest, and extreme gradient boosting. Nine variables, including age, gravidity, parity, menopause status, cytological results, high-risk human papillomavirus (HR-HPV) infection type, HR-HPV multi-infection, transformation zone (TZ) type, and colposcopic impression, were used for model construction. Results: Colposcopic impression, HR-HPV results, and cytology results were the top three variables that determined model performance among all included variables. In the internal validation set, six ML models that integrated demographics, screening results, and colposcopic impression showed significant improvements in the area under the curve (AUC) (0.067 to 0.099) and sensitivity (11.55% to 14.88%) compared with colposcopists. Greater increases in AUC (0.087 to 0.119) and sensitivity (17.17% to 22.08%) were observed in the six models with the external validation set. Conclusions: By incorporating demographics, screening results, and colposcopic impressions, ML improved the AUC and sensitivity for detecting HSIL+ in patients referred for colposcopy. Such models could transform the subjective experience into objective judgments to help clinicians make decisions at the time of colposcopy examinations.

The onset of puberty has become earlier over the decades, and nutrients and diet are related to the timing of puberty onset. Hence, we aimed to investigate the association between diet or nutrients in infancy, childhood and early puberty. PubMed, Embase, and Cochrane library were searched systematically up to 15 April 2022. The pooled relative risks (RRs) or regression coefficients (beta) were estimated using the random-effect model or fixed-effect model according to the heterogeneity between studies. Twenty-two articles on diet or nutrients in childhood and six about breastfeeding in infancy were included. The prolonged breastfeeding duration in infancy could reduce the risk of early menarche (beta 0.31, 95% CI: 0.01, 0.60, p = 0.045). The high intake of yogurt was associated with a 35% reduction in the risk of earlier menarche (RR 0.65, 95% CI: 0.47, 0.89, p = 0.008). Girls with severe food insecurity experienced later menarche (RR 0.81, 95% CI: 0.67, 0.98, p = 0.027). Conversely, due to the high intake of protein, the risk of early menarche increased by 8% (RR 1.08, 95% CI: 1.01, 1.16, p = 0.016). High intake of yogurt, longer duration of breastfeeding, and food insecurity decreased the possibility of earlier menarche, while high intake of protein increased that risk. As a modifiable factor, diet and nutrients in infancy and childhood provide new insights into the future prevention of early puberty.

We experimentally investigate how initial entanglement between the system and environment can be detected in an open system by using some prior knowledge of the joint evolutions. The protocol we employed requires classical optimization on the results after performing measurements on the system state. Such an approach does not require a full 2-qubit QST, and works in scenarios where one has access to the system only. We demonstrate the protocol on both pure entangled states and mixed entangled states. The obtained results show the experimental accessibility and validity of the protocol. Compared with the previous methods, which also assume access only to the system, this protocol is less demanding in terms of measurement and state preparation. The experimental results also show that, using the knowledge of the interaction, we can fine-tune the protocol, thus showing the potential of the protocol for developing experimentally feasible and practical entanglement detection methods.

Recently published guidelines depend upon screening for cervical precancer risk stratification; however, colposcopy provides key information. There is no data from developing countries that could be used comparatively. Therefore, we assessed the potential benefits of intercalating colposcopic impressions with screening results to detect cervical precancers through a multicenter, cross-sectional study of a Chinese population. Anonymized data from 6012 women with cytologic assessment, human papillomavirus (HPV) testing, colposcopic impressions, and histological results were analyzed. Univariate and multivariate analysis showed that high-grade squamous intraepithelial lesion (HSIL) cytology, HPV16/18+, and/or high-grade colposcopic impressions markedly increased cervical precancer risk, while high-grade colposcopic impressions were associated with the highest risk. The risk of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) ranged from 0% for normal/benign colposcopic impressions, 19% increased risk of CIN3+, even in participants without HSIL+ cytology and/or HPV16/18+. Regardless of screening outcomes, normal/benign colposcopic impressions were associated with the lowest risk of CIN3+ (

The high-temperature oxidation behaviors of polycrystalline Co-30Ni-10Al-4W-4Ti-2Ta superalloys with Cr contents ranging from 1 to 5 at.% are characterized at 900 °C to provide benchmark data for the alloy design of the CoNi-based superalloys. The mass gain curves for all three alloys exhibit parabolic growth, and the addition of 5Cr at.% is sufficient to decrease the oxidation rate by two orders of magnitude compared to the Cr-free alloy. Furthermore, cross-sectional findings reveal that these three alloys form qualitatively similar oxide scales composed of an outer oxide layer of Co3O4 and CoAl2O4 phase on top of an Al2O3 scale, following the inner oxide layers of Cr2O3, TiO2, and TiTaO4, and internally oxidized Al2O3 precipitate. The alloy forms a chromium-rich oxide scale as the Cr addition increased, and the concentration of Cr in the scale/alloy interface increases, promoting the growth of Cr2O3, while CoAl2O4 and Co3O4 nucleation is inhibited. The results further indicate that Cr has a superior effect on improving the oxidation resistance of CoNi-based alloys and that a higher content of Cr can assist the formation of a continuous Al2O3, Cr2O3, and TiTaO4 layers, which in turn hampers outer Co and Ni, and inward oxygen flux.

The accuracy of the circular grating is the key point for control precision of the single gimbal control moment gyroscope servo system used in civilian micro-agile satellites. Instead of using the multi reading heads to eliminate eccentricity errors, an algorithm compensation method based on a calibration experiment using a single reading head was proposed to realize a low-cost and high accuracy angular position measurement. Moreover, the traditional hardware compensation method using double reading heads was also developed for comparison. Firstly, the single gimbal control moment gyroscope system of satellites was introduced. Then, the errors caused by the installation of the reading head were studied and the mathematic models of these errors were developed. In order to construct the compensation function, a calibration experiment using the autocollimator and 24-sided prism was performed. Comparison of angle error compensation using the algorithm and hardware method was presented, and results showed that the algorithm compensation method proposed by this paper achieved the same accuracy level as the hardware method. Finally, the proposed method was further verified through a control system simulation.

The rotating stall is an unstable flow phenomenon of pump turbines in pump mode, which is of increasing concern to scientists and engineers working on pump turbines. However, at present, various studies are carried out based on CFD (computational fluid dynamics) simulation, while directly measured data and experimental research on flow fields are seldom reported. By utilizing PIV (particle image velocimetry) measuring equipment, the flow field within the guide vane zone of a low specific speed pump turbine in pump mode was measured. By measuring and analyzing the transient flow field, the evolutionary process of the rotating stall within the guide vane passages was determined. We found that for all three tested guide vane openings, regardless of whether the positive slope appeared or not, a pre-stall operating point was found for each opening in the process of decreasing the flow rate. The analysis of the loss within the flow field indicated that the dissipation-induced loss increased greatly after the rotating stall appeared. The pump performance curves at the three guide vane openings showed an inflection at the pre-stall point. When the flow rate is larger than that of the pre-stall point, the head of the pump turbine dramatically increases as the flow rate decreases. However, when the flow rate is smaller than the pre-stall point, such increases noticeably slows down. The research results showed that whether the positive slope on the pump performance curve occurred or not, instability caused by the rotating stall should be of great concern.

This paper presents a comprehensive investigation on the self-sustained oscillation of silicon carbide (SiC) MOSFETs. At first, based on the double pulse switching test, it is identified that the self-sustained oscillation of SiC MOSFETs can be triggered by two distinct test conditions. To investigate the oscillatory criteria of the two types of self-sustained oscillation, a small-signal ac model is introduced to obtain the transfer function of the oscillatory system. The instability of the oscillation is thereby determined by the two conjugate pole pairs of the transfer function. By analyzing the damping ratios of the two pole pairs, the parametric sensitivity of various circuit and device’s parameters on the two types of self-sustained oscillation are obtained. The analyses reveal the oscillatory criteria of the self-sustained oscillation for SiC MOSFETs. Based on the oscillatory criteria, necessary methods are proposed to prevent the oscillation. The proposed oscillation suppression methods are validated by the experiment at the end of the paper.

With the development of microelectronic packaging and increasingly specific service environment of solder joints, much stricter requirements have been placed on the properties of lead-free solders. On account of small size effect and high surface energy, nanoparticles have been widely used to improve the microstructure and properties of lead-free solders. Therefore, the composite solders bearing nanoparticles have recently attracted wide attention. This article reviewed the recent research on SnAgCu, SnBi, and SnZn composite solder alloys and introduced the effect of nanoparticles on their microstructure, mechanical properties, wettability, and reliability. The mechanism of nanoparticles strengthening was analyzed and summarized. In addition, the shortcomings and future development trends of nanoparticle-reinforced lead-free solders were discussed, which is expected to provide some theoretical reference for the application of these composite solder in 3D IC package.

The nonspecific adsorption of proteins and bacteria on the surface of polydimethylsiloxane (PDMS) had been a serious concern in a wide range of applications, such as medical devices. In order to improve the anti-adhesive and antibacterial capability, bare silver nanoparticles (AgNPs, ~15 nm) were generated in-situ on their surface without extra reducing and stabilizing agents. The main reason for this was that the SiO2 microspheres that are covalent bonded to the bulked PDMS could not only generate AgNPs spontaneously but also insure that no AgNPs were released to the environment. Meanwhile, the thiol-group-functionalized SiO2 microspheres self-assembled on the surface of PDMS by thiol-vinyl click reaction without any impact on their biomedical applications. After the modification of SiO2 microspheres with AgNPs, the surface of PDMS showed a smaller water contact angle than before, and the adhesion and growth of E. coli and Bacillus subtilis were effectively inhibited. When the monolayer of SiO2 microspheres with AgNPs was assembled completely on the surface of PDMS, they present improved bacterial resistance performance (living bacteria, 0%). This approach offers an antibacterial and anti-adhesive surface bearing small and well-defined quantities of in-situ generated AgNPs, and it is a novel, green, simple, and low-cost technique to generate AgNPs on soft biomedical substrates.

The tin whisker inhibition in RE-doped Sn-Zn soldered joints was investigated. The results indicated that after aging treatment at 150 °C, with the proper addition ratio of Ga and Nd, no obvious NdSn3 phase nor tin whisker growth was observed in the soldered joints. By replacing the Sn-Nd phase with a Ga-Nd phase, the risk of tin whisker growth caused by the oxidation of RE-phase was significantly inhibited even in soldered joints with additional excessive contents of Nd. The IMC layer in soldered joints with optimal addition showed a relatively regular shape after aging treatment, making the soldered joint maintain preferable mechanical performance. The results would be available for guiding the study of tin whisker growth inhibition method.

China is actively promoting ocean territory construction, and how to design low-energy buildings to fit the unique climate of tropical island regions has received much attention. The heat transfer coefficient of a building external surface plays a vital role in calculating air-conditioning load accurately. To obtain reasonable heat transfer coefficients in the tropical island region, this study introduced a naphthalene sublimation experiment to conduct full-scale measurements on convective heat transfer coefficients (CHTCs) in the tropical island region, and proposed a simplified calculation model of evaporative heat transfer coefficients (EHTCs). Results indicated that the function expression between CHTC and wind speed was CHTC = 5.56 + 4.48u (R2 = 0.94), and it was validated to be reliable. Furthermore, compared with CHTCs and radiation heat transfer coefficients (RHTCs), the EHTC had a wider changing range, owing to rainfall effects. Moreover, whether evaporation was considered or not, the difference of total heat transfer coefficients (THTCs) on building external surfaces was 5.2 W/(m2·K) for the whole year, so evaporation cannot be ignored directly. Additionally, THTCs with consideration of evaporation in winter and summer were 33.4 W/(m2·K) and 38.9 W/(m2·K) severally, which are much larger than the recommended values in the Chinese standard. This study would make up for the lack of surface heat transfer coefficients in energy conservation design of tropical island buildings.

The microstructure and properties of a Cu/304 stainless steel dissimilar metal joint brazed with a low silver Ag16.5CuZnSn-xGa-yCe braze filler after aging treatment were investigated. The results indicated that the addition of Ce could reduce the intergranular penetration depth of the filler metal into the stainless steel during the aging process. The minimum penetration depth in the Ag16.5CuZnSn-0.15Ce brazed joint was decreased by 48.8% compared with the Ag16.5CuZnSn brazed joint. Moreover, the shear strength of the brazed joint decreased with aging time while the shear strength of the AgCuZnSn-xGa-yCe joint was still obviously higher than the Ag16.5CuZnSn joint after a 600 h aging treatment. The fracture type of the Ag16.5CuZnSn-xGa-yCe brazed joints before aging begins ductile and turns slightly brittle during the aging process. Compared to all the results, the Ag16.5CuZnSn-2Ga-0.15Ce brazed joints show the best performance and could satisfy the requirements for cost reduction and long-term use.

With the increasing demands for better transmission speed and robust quality of service (QoS), the capacity constrained backhaul gradually becomes a bottleneck in cooperative wireless networks, e.g., in the Internet of Things (IoT) scenario in joint processing mode of LTE-Advanced Pro. This paper focuses on resource allocation within capacity constrained backhaul in uplink cooperative wireless networks, where two base stations (BSs) equipped with single antennae serve multiple single-antennae users via multi-carrier transmission mode. In this work, we propose a novel cooperative transmission scheme based on compress-and-forward with user pairing to solve the joint mixed integer programming problem. To maximize the system capacity under the limited backhaul, we formulate the joint optimization problem of user sorting, subcarrier mapping and backhaul resource sharing among different pairs (subcarriers for users). A novel robust and efficient centralized algorithm based on alternating optimization strategy and perfect mapping is proposed. Simulations show that our novel method can improve the system capacity significantly under the constraint of the backhaul resource compared with the blind alternatives.

Hydrogel antibacterial agent is an ideal antibacterial material because of its ability to diffuse antibacterial molecules into the decayed area by providing a suitable microenvironment and acting as a protective barrier on the decay interface. The biocompatibility and biodegradation make the removal process easy and it is already widely used in medical fields. However, there have been few reports on its application for controlling postharvest diseases in fruit. In this study, the Chitosan–silver (CS–Ag) complex hydrogels were prepared using the physical crosslinking method, which is used for controlling postharvest diseases in grape. The prepared hydrogels were stable for a long period at room temperature. The structure and surface morphology of CS–Ag composite hydrogels were characterized by UV-Vis, FTIR, SEM, and XRD. The inhibitory effects of CS–Ag hydrogel on disease in grape caused by P. expansum, A. niger, and B. cinerea were investigated both in vivo and in vitro. The remarkable antibacterial activity of CS–Ag hydrogels was mainly due to the combined antibacterial and antioxidant effects of CS and Ag. Preservation tests showed that the CS–Ag hydrogel had positive fresh-keeping effect. This revealed that CS–Ag hydrogels can play a critical role in controlling fungal disease in grapes.