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Many scholars have focused on the workability and mechanical properties of fly ash (FA)- ground granulated blast furnace slag (GGBS) geopolymer. To enhance the compressive strength of geopolymer, zeolite powder was added in the present study. A series of experiments were carried out to investigate the effect of using zeolite powder as an external admixture on the per-formance of FA-GGBS geopolymer, 17 sets of experiments were designed and tested to deter-mine the unconfined compressive strength based on the response surface methodology, and then, the optimal parameters were obtained via modeling of 3 factors (zeolite powder dosage, alkali exciter dosage, and alkali exciter modulus) and 2 levels of compressive strength (3 d and 28 d). The experimental results showed that the strength of the geopolymer was the highest when the three factors were 13.3%, 40.3%, and 1.2. Finally, a combination of scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and 29Si nuclear magnetic resonance (NMR) analysis was used to conduct micromechanical analysis and explain the reaction mechanism from a microscopic perspective. The SEM and XRD analysis revealed that the microstructure of the geopolymer was the densest when the zeolite powder was doped at 13.3%, and the strength increased accordingly. The NMR and Fourier transform infrared spectroscopy analyses revealed that the absorption peak wave number band shifted toward the lower wave number band under the optimal ratio, and the silica–oxygen bond was replaced by an aluminum–oxygen bond, which generated more aluminosilicate structures.

Summary: This article addresses the fuzzy finite‐time command filtering tracking control problem for switched nonlinear systems with input nonlinearities via using backstepping technique. An equivalent transformation method is proposed for the purpose of handling the impediment problem caused by the nonlinearity of control input. Finite‐time command filtering control technology can solve the "explosion of complexity" issue, which is caused by the multiple derivation of virtual controllers appeared in the classic backstepping control. A filtering compensation scheme is developed to reduce the filtering error. By combining the fuzzy logic system's approximation ability and the finite‐time theory, a new fast convergence adaptive control scheme is proposed so that the output of the system can converge to a small area near the desired signal and the boundedness of all signals of the controlled system can be assured in finite time. Finally, a simulation example successfully verifies the feasibility of the developed control scheme. [ABSTRACT FROM AUTHOR]

This work mainly studies the issue of predefined time and accuracy adaptive fault-tolerant control for strict-feedback nonlinear systems with multiple faults. The faults in the controlled system include actuator faults and external system faults. The unknown functions for nonlinear systems are approximated by fuzzy logic systems (FLSs). And then, according to the backstepping technique and the predefined time stability theory, an adaptive fuzzy control algorithm is presented, which can make sure that all closed-loop system signals remain predefined time bound and the tracking error converges to a predefined accuracy within the predefined time. Ultimately, the effectiveness of the presented control algorithm is proved through two simulation examples. [ABSTRACT FROM AUTHOR]

Age related macular degeneration(ARMD)is the leading cause of blindness in people over 65 years of age. The need for research on effective treatments of ARMD has led to the development of multiple animal models. ARMD is a complex process involving interaction of age, genetic and environmental factors. Animal models have reconstructed many of the histological features in ARMD, making it possible to better understand the underlying pathogenesis of the disease. Although no model can replicate all the phenotypes of human ARMD, it can express different characteristics of ARMD, revealing the roles of chronic oxidative damage, inflammation, immune dysregulation and lipid metabolism in the development of ARMD. This article will review the various ARMD animal models that have been reported. By analyzing the advantages and limitations of each model, it will provide some help for the selection of appropriate animal models for ARMD research and provide new modeling ideas.

Network security assessment helps to grasp the current and future risks of the network information system clearly,and gives corresponding security suggestions and countermeasures.Model of network security assessment and analysis is an important research direction and content,for which there is no review to give a comprehensive summary or analysis.A review of common network security evaluation and analysis model was given.The model that focus on attack was introduced,such as the attack tree,attack graph and kill chain,then the model that focus on network defense or offensive and defensive interaction was explained,such as attack surface,cyber epidemic model,Petri nets and automation machine,giving introduction to the basic concept,application field,modeling analysis process,advantages and disadvantages of the models.Then,typical examples were given to illustrate the application of the models in network defense technology evaluation and analysis.

The white-backed planthopper, Sogatella furcifera, is a phloem sap feeder that secretes watery and gelling saliva during feeding. In this study, we identified the major proteins in watery saliva of S. furcifera by shotgun LC-MS/MS analysis combined with transcriptomic analysis. A total of 161 proteins were identified, which were divided into 8 function categories, including enzymes, transporter, calcium ion binding protein, salivary sheath protein, cytoskeleton protein, DNA-, RNA-, and protein-binding or regulating proteins, other non-enzyme proteins and unknown proteins. Gene expression pattern of 11 secretory proteins were analyzed by real time quantitative-PCR. We detected the mucin-like protein, which had a unique expression level in salivary gland, most likely to be a candidate effector involved in regulation of plant defense. This study identified the watery saliva component of S. furcifera and it provided a list of proteins which may play a role in interaction between S. furcifera and rice.

In this article, we investigate the finite-time output feedback control issue for switched nonlinear systems. In the design procedure, fuzzy logic systems are used for identifying the unknown functions in switched nonlinear systems. A common state observer is constructed such that the unmeasured states can be measured. Based on the framework of the backstepping algorithm, an observer-based finite-time adaptive tracking control strategy is proposed via the common Lyapunov function approach. The stability analysis process confirms in detail that all the closed-loop signals are bounded under arbitrary switchings and the tracking error can converge to a small neighbourhood of the origin after a finite period of time. In order to verify the feasibility of the proposed control scheme, a numerical simulation example is shown in this paper. [ABSTRACT FROM AUTHOR]

Hyperbaric oxygen therapy (HBOT) is a clinical treatment in which a patient breathes pure oxygen for a limited period of time at an increased pressure. Although this therapy has been used for decades to assist wound healing, its efficacy for many conditions is unproven and its mechanism of action is not yet fully clarified. This study investigated the effects of HBOT on wound healing using a diabetes-impaired pressure ulcer rat model. Seven weeks after streptozotocin-induced diabetes in rats (n = 55), a pressure ulcer was created on dorsal skin. Subsequently, animals received HBOT during 6 weeks following a standard clinical protocol (HBOT group with varying endpoints up to 42 days post-wounding) versus controls without HBOT. Capillary venous oxygen saturation (SO2) showed a significant increase in the HBOT group on day 24; however, this increase was significant at this time point only. The quantity of hemoglobin in the micro-blood vessels (rHB) showed a significant decrease in the HBOT group on days 21 and 42, and showed a trend to decrease on day 31. Blood flow in the microcirculation showed a significant increase on days 17, 21 and 31 but a significant decrease on days 24 and 28. Inflammation scoring showed significantly decreased CD68 counts in the HBOT group on day 42, but not in the early stages of wound healing. Animals in the HBOT group showed a trend for an increase in mean wound breaking strength on day 42. [ABSTRACT FROM AUTHOR]

Wound healing in diabetes is frequently impaired and its treatment remains a challenge. Hyperbaric oxygen therapy (HBOT) receives a wide attendance and is often used as a last resort treatment option, however, its effectiveness for many conditions is unproven. We tested the effect of HBOT on healing of diabetic ulcers in an animal experimental setting. Experimental diabetes was induced by intraperitoneal injection of streptozotocin. Four weeks after diabetes induction, rats were ulcerated by clamping a pair of magnet disks on the dorsal skin for 16 h. After magnet removal, the animals received HBOT, daily on weekdays, for 4 weeks. To examine the effect of HBOT on diabetes impaired wound healing, the degree of wound tissue perfusion, inflammation, angiogenesis, and tissue breaking strength were evaluated. HBOT effects on the degree of inflammation and number of blood vessels could not be observed. HBOT improved the tissue breaking strength of the wound, however, this did not reach statistical significance. Twenty hours after ending the HBOT, a significantly improved oxygen saturation of the hemoglobin at the venous end of the capillaries and the quantity of hemoglobin in the micro-blood vessels was measured. [ABSTRACT FROM AUTHOR]

BSTRACT [ABSTRACT FROM AUTHOR]

Heparan sulfate glycosaminoglycans (HS-GAGs) are not only the structural elements of tissue architecture but also regulate the bioavailability and transduction pathways of heparan sulfate-bound polypeptides released by cells or the extracellular matrix. Heparan sulfate-bound polypeptides include inflammatory mediators, chemokines, angiogenic factors, morphogens, and growth-promoting factors that induce cell migration, proliferation, and differentiation in wound healing. OTR4120, a polymer engineered to mimic the properties of HS-GAGs, is used to replace the natural HS-GAGs that are degraded during wound repair, and enhance the tissue regeneration by preserving the cellular microenvironment and the endogenous signals needed for tissue regeneration. We previously demonstrated that OTR4120 treatment had a long-term effect on increasing breaking strength and vasodilation in healing rat full-thickness excisional wounds. The present study investigates the underlying mechanisms of the effects of OTR4120 treatment in improving the quality of cutaneous wound repair. We found that OTR4120 treatment stimulated inflammation resolution and increased neovascularization. OTR4120 treatment also promoted epidermal migration and proliferation during reepithelialization. Moreover, the granulation tissue formation and collagen maturation were improved in OTR4120-treated wounds. Three months after wounding, the effects of OTR4120 treatment on vascularization and inflammation resolution were normalized, except for an improved neodermis. We conclude that OTR4120 is a potential matrix therapeutic agent that ensures the quality of normal cutaneous wound repair and may restore impaired wound healing characterized by deficient angiogenesis and prolonged inflammation. [ABSTRACT FROM AUTHOR]

The Fifth Assessment Report of the Intergovernmental Panel on Climate change (IPCC) shows that climate change poses severe risks to the Belt and Road region and could cut future crop production. Identifying the positions and features of hotspots, which refer to regions with severe yield loss at 1.5 °C global warming, is the key to developing proper mitigation and adaptation policies to ensure regional food security. This study examined yield loss hotspots of four crops (maize, rice, soybean and wheat) at 1.5 °C global warming under RCP8.5. Yield data were derived from simulations of multiple climate-crop model ensembles from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP). Hotspots were identified by setting a threshold of the 10th percentile of crop yields during the reference period (1986–2005). To quantify the likelihood of crop yield loss hotspots within multi-model ensembles, the agreement of model combinations for hotspots was calculated for each crop at the grid scale with 0.5° × 0.5° spatial resolution. Results revealed spatial heterogeneity of cultivation structure and hotspot likelihood for four crops. The four crops' production of SA (South Asia) and SEA (Southeast Asia) accounts for more than 40% of the total production in the Belt and Road region, roughly four times the amount produced in CEE (Central and Eastern Europe) and NEA (Northeast Asia). Besides, the hotspots likelihood of maize, rice and soybean is generally larger in SA/SEA than that in CEE/NEA which means the risk of yield reduction is higher in the current main agricultural area. According to IPCC's classification rules for likelihood, four crops' hotspot patterns were displayed under the 1.5 °C global warming. As the highest-yielding crop, maize shows the largest proportion of "likely" hotspots (hotspot likelihood > 66%), which is about 6.48%, accounting for more than four times that of the other three crops. In addition, four crops' hotspots are mainly distributed in SEA and SA. Overall, SEA and SA are vulnerable subregions and maize is the vulnerable crop of the Belt and Road region. Our results could provide information on target areas where mitigation or adaptations are needed to reduce the adverse influence of climate change in the agricultural system. [ABSTRACT FROM AUTHOR]

ReGeneraTing Agents (RGTAs), a family of polymers engineered to protect and stabilize heparin-binding growth factors, have been shown to promote tissue repair and regeneration. In this study, the effects of one of these polymers, RGTA OTR4120, on healing of full-thickness excisional wounds in rats were investigated. Two 1.5 cm diameter circular full-thickness excisional wounds were created on the dorsum of a rat. After creation of the wounds, RGTA OTR4120 was applied. The progress of healing was assessed quantitatively by evaluating the wound closure rate, vasodilatory capability, and wound breaking strength. The results showed a triple increase of the local vascular response to heat provocation in the RGTA OTR4120-treated wounds as compared with vehicle-treated wounds. On days 14 and 79 after surgery, the wounds treated with RGTA OTR4120 gained skin strength 12% and 48% of the unwounded skin, respectively, and displayed a significantly increased gain in skin strength when compared with control animals. These results raise the possibility of efficacy of RGTA OTR4120 in accelerating surgically cutaneous wound healing by enhancing the wound breaking strength and improving the microcirculation. [ABSTRACT FROM AUTHOR]

Abstract: We have developed a multiplexed and miniaturized TB serological assay with the aim of identifying (combinations of) antigens that maximally discriminate between TB and non-TB patients. It features a microarray accommodating 54 TB antigens, less than 1 μl serum consumption and an indirect immunofluorescence detection protocol. With a panel of 20 TB and 80 non-TB sera we ranked combinations of TB antigens with respect to sensitivity and specificity of TB detection by means of logistic step-forward regression analysis. The highest-ranking TB antigen combination had an area-under-the-curve of the receiver–operator-characteristics (ROC) of 0.95. We also identified an antigen that on its own provided good specificity and sensitivity of TB detection (Ara6–BSA; area-under-the-ROC curve: 0.90). These area-under-the-ROC curve values are exceptionally high for a serological TB assay. We conclude that TB antigen microarrays permit rapid identification of TB antigens that, either alone or in combination, discriminate maximally between TB and non-TB patients and that such identification provides an excellent starting point for developing point-of-care diagnostic assays. [Copyright &y& Elsevier]

In the Hengduan Mountain region, soil erosion is the most serious ecological environmental problem. Understanding the impact mechanism of water yield and soil erosion is essential to optimize ecosystem management and improve ecosystem services. This study used the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and Revised Universal Soil Loss Equation (RUSLE) models to separate the relative contributions of land use and climate change to water yield and soil erosion. The results revealed that: (1) Although soil and water conservation has been strengthened in the past 25 years, both water yield and soil erosion increased from 2010 to 2015 due to the conversion of woodland to grassland, which indicates that continuous benefits after the implementation of ecological restoration projects were not obtained; (2) Climate change played a decisive role in water yield and soil erosion changes in the Hengduan Mountain region from 1990 to 2015, and soil erosion was not only related to the amount of precipitation but also closely related to precipitation intensity; (3) The contribution of land use and climate change to water yield was 26.94% and 73.06%, while for soil erosion, the contribution of land use and climate change was 16.23% and 83.77%, respectively. [ABSTRACT FROM AUTHOR]

During the operation of load cell, heat is generated by the strain gauge and the electronics on the PCB board, which leads to temperature gradients within the sensor itself. These temperature gradients are unstable at different ambient temperatures. Compensation inaccuracies can also occur when compensating for sensor measurements at different temperatures This paper proposes a method to change the position of temperature compensation resistors to address errors caused by the temperature field effect of the strain gauge sensor itself. Without affecting the sensor's strain measurement, the correctness of the proposed method is demonstrated through steady-state thermal simulation results in ANSYS and experimental results, effectively addressing errors caused by unstable temperature gradients during the operation of strain gauge sensors., (© 2024. The Author(s).)

This article investigates the neural-network-based adaptive predefined-time tracking control problem for switched nonlinear systems. Neural networks are employed to approximate the unknown part of nonlinear functions. The finite-time differentiators are introduced to estimate the first derivative of the virtual controllers. Then, a novel adaptive predefined-time controller is proposed by utilizing the backstepping control technique and the common Lyapunov function (CLF) method. It is explained by the theoretical analysis that the developed controller guarantees that all signals of the switched closed-loop systems are bounded under arbitrary switchings and the tracking error converges to zero within the predefined time. A simulation is shown to verify the validity of the developed predefined-time control approach.

Objective: While prior reports have characterized visible changes in neuroimaging findings in individuals suffering from sudden sensorineural hearing loss (SSNHL), the utility of regional homogeneity (ReHo) as a means of diagnosing SSNHL has yet to be established. The present study was thus conducted to assess ReHo abnormalities in SSNHL patients and to establish whether these abnormalities offer value as a diagnostic neuroimaging biomarker of SSNHL through a support vector machine (SVM) analysis approach., Methods: Resting-state functional magnetic resonance imaging (rs-fMRI) analyses of 27 SSNHL patients and 27 normal controls were conducted, with the resultant imaging data then being analyzed based on a combination of ReHo and SVM approaches., Results: Relative to normal control individuals, patients diagnosed with SSNHL exhibited significant reductions in ReHo values in the left cerebellum, bilateral inferior temporal gyrus (ITG), left superior temporal pole (STP), right parahippocampal gyrus (PHG), left posterior cingulum cortex (PCC), and right superior frontal gyrus (SFG). SVM analyses suggested that reduced ReHo values in the left cerebellum were associated with high levels of diagnostic accuracy (96.30%, 52/54), sensitivity (92.59%, 25/27), and specificity (100.00%, 27/27) when distinguishing between SSNHL patients and control individuals., Conclusion: These data suggest that SSNHL patients exhibit abnormal resting-state neurological activity, with changes in the ReHo of the left cerebellum offering value as a diagnostic neuroimaging biomarker associated with this condition., (Copyright © 2022 Liu, Fan, Zhan, Huang, Cao, Xiang, Tian, Ren, Tong and Li.)

Background: Currently there are two main sources of mortality data with cause of death assignments in China. Both sources-the Ministry of Health-Vital Registration system and the Chinese Disease Surveillance Point system-present their own challenges. A new approach to cause of death assignment is a smartphone-based shortened version of a verbal autopsy survey. This study evaluates the feasibility and acceptability of this new method conducted by township health care providers (THP) and village doctors (VD) in rural China, where a large proportion of deaths occur in homes and cause of death data are inaccurate or lacking., Methods: The Population Health Metrics Research Consortium mobile phone-based shortened verbal autopsy questionnaire was made available on an Android system-based application, and cause of death was derived using the Tariff method (Tariff 2.0); we called this set of tools "msVA." msVA was administered to relatives of the deceased by six THPs and six VDs in 24 villages located in six townships of Luquan County, Hebei Province, China. Subsequently, interviews were conducted among 12 interviewers, 12 randomly selected respondents, and five study staff to assess the feasibility and acceptability of using msVA for mortality data collection., Results: Between July 2013 and August 2013, 268 deaths took place in the study villages. Among the 268 deaths, 227 VAs were completed (nine refusals, 31 migrations and one loss of data due to breakdown of the smartphone). The average time for a VA interview was 21.5 ± 3.4 min (20.1 ± 3.5 min for THP and 23.2 ± 4.1 min for VD). Both THPs and VDs could be successful interviewers; the latter needed more training but had more willingness to implement msVA in the future. The interviews revealed that both interviewers and relatives of the deceased found msVA to be feasible, acceptable, and more desirable than traditional methods. The cost of conducting a new VA was $8.87 per death., Conclusions: Conduction of msVA by VDs in their own villages was feasible and acceptable in rural northern China. Broader implementation of msVA across rural China could potentially improve the coverage and quality of cause of death data, allowing for better national health evaluation and program planning.

Objective: To analyze and optimize extraction technics of Polygonum orientale flowers by response surface methodology., Methods: With the index for the content of taxifolin in flowers of Polygonum orientale, the effect of three factors such as concentration of alcohol, extraction time and solvent-solid ratio was designed by Box-Behnken central composite. Extraction technic parameters of Polygonum orientale flowers was optimized by response surface methodology., Results: The optimizing extraction conditions of Polygonum orientale flowers were as follows: ethanol concentration was 65%, extracting time was 129 min and solvent-solid ratio was 18. Under the conditions, the average yield of taxifolin in 3 validation experiments was 2.79 mg/g., Conclusion: Optimizing extraction technics by response surface methodology is reasonable, simple, and has good predictability.

Objective: To establish a characteristic HPLC fingerprint of Polygonum orientale inflorescence, and to provide reference for its quality evaluation., Methods: Taxifolin was used as reference. HPLC analysis was carried out with Diamonsil C18 column (200 mm x 4.6 mm, 5 microm) using acetonitrile -0.1% phosphoric acid(gradient elution)as mobile phase at flow rate of 1.0 mL/min. The detection wavelength was set at 280 nm and the column temperature was 30 degrees C., Results: Eighteen common peaks were pointed out from the HPLC fingerprint of Polygonum orientale inflorescence from 12 different habitats. Among of them,four common peaks were identified as taxifolin, catechin, gallic acid and 3,3'-dimethyl ellagic acid-4-O-beta-D-glucoside. Analyzed by "Similarity Evaluation for Chromatographic Fingerprint of Traditional Chinese Medicine" software, the HPLC fingerprint similarities of 12 samples were more than 0.9., Conclusion: This method is repeatable and exclusive. It can be used for identification and quality control of Polygonum orientale inflorescence.

Objective: To find out the correlation between the content of taxifolin in Polygonum orientale and the storage time., Method: HPLC was used to determine taxifolin. The chromatographic condition was as following: Diamonsil C18 column (4.6 mm x 200 mm, 5 microm), mobile phase acetonitrile -0.1% phosphoric acid (gradient elution), the detection wavelength 290 nm and flow rate 1.0 mL x min(-1), the column temperature 30 degrees C., Result: The injection volume of taxifolin was in good linearity within 0.07 and 0.35 microg, the average recovery was 99.7% with RSD 0.2%. Taxifolin content was 0.84, 1.36, 1.75, 1.99 mg x g(-1) corresponding to storage time of 10, 7, 6, 5 years, respectively., Conclusion: The content of taxifolin decreased with the storage time. When the storage period is more than six years, the content is lower than that required by Chinese Pharmacopoeia (2010 version). This method has a good repeatability and accuracy, it provides a scientific reference for clinical use and quality evaluation of P. orientale.

Objective: To establish a HPLC-DAD method for the determination of axifolin, naringenin, quercetin and kaempferol in Cudrania tricuspidata and C. cochinchinensis in order to provide a scientific reference for species identification and quality evaluation, by establishing., Method: The determination was performed by HPLC-DAD on an Agilent C18 column (4.6 mm x 150 mm, 5 microm) by gradient elution (0-15 min, 35%-50% A; 15-30 min, 50% - 65% A) using methanol (A) and 0.1% phosphoric acid (B) as the mobile phase. The flow rate was 1 mL x min(-1). The detection wavelength was 290 nm for taxifolin and naringenin, 365 nm for quercetin and kaempferol with column temperature at 30 degrees C., Result: The content of axifolin and quercetin in the root of C. tricuspidata were remarkably higher than that in the root of C. cochinchinensis, and the content in stem of C. tricuspidata was also higher than that in the stem of C. cochinchinensis, the content of axifolin and quercetin was variable in different species. The content of naringenin and kaempferol in the root of C. cochinchinensis was visibly higher than that in the root of C. tricuspidata, and the content in the stems of the two herbs was similar, the content of naringenin and kaempferol was visibly variable in different medicinal parts of the herb, but similar between the two herbs., Conclusion: There's some difference of the content of the four ingredients in different medicinal parts and different herbs, so clinical use should not be confused.