Research on Rutting Model of Semi-Rigid Asphalt Pavement Based on Hamburg Rutting Test

In order to establish a more effective rutting model of semi-rigid asphalt pavement, after sampling on-site,the Hamburg rutting test was conducted to analyze the relationship between ambient temperature, load magnitude,number of load actions and rutting depth; Taking Shami model as a reference,the environmental temperature,load size,load times and asphalt thickness are taken as model parameters;the rutting prediction models of upper,middle and lower surfaces of semi-rigid asphalt pavement structure are established by multiple linear regression analysis,and the models are modified by 6 sections of 4 expressways.The model is used to test 8 sections of 5 expressways,the results show that the average error rate of the calculated value of the model is 15.16%,which is obviously lower than the average error rate of 27.32% of the calculated value of the rut model in the current standard.Therefore,the model has high accuracy and can provide theoretical guidance for the design and maintenance of semi-rigid asphalt pavement

Evaluation of the cytotoxic effects of sodium hypochlorite on human dental stem cells

Purpose: To investigate the influence of sodium hypochlorite (NaOCl) on human dental stem cell proliferation and differentiation.Method: Dental pulp stem cells (DPSCs), periodontal ligament stem cell (PDLSCs), and gingival mesenchymal stem cells (GMSCs) were treated with NaOCl. Cell viability was evaluated with cellular counting kit-8 (CCK8), and cellular adenosine triphosphate (ATP) levels were analyzed by bromodeoxyuridine (BrdU) incorporation and subsequent flow cytometry. Quantitative polymerase chain reaction (qPCR) and western blotting were performed to detect the expressions of differentiation markers.Results: The viability and ATP levels of all three stem cells types were impaired by NaOCl in a concentration- and time-dependent manners. However, the decrease ATP in GMSCs was less than the other two stem cell population (p < 0.05). NaOCl treatment significantly suppressed the proliferation of dental stem cells (p < 0.05). With regard to differentiation marker expression levels, the decrease in Stro-1 was greater in treatment groups when compared to control on Day 7, while increase in levels of dentin sialophosphoprotein (DSPP), bone sialoprotein (BSP), and osteocalcin (OC) was smaller (p < 0.05). The expressional changes of Stro-1, DSPP, BSP, and OC were more prominent in DPSMs and PDLSCs than in GMSCs.Conclusion: NaOCl dose-dependently impairs the viability, proliferation and differentiation of dental stem cells. Thus, its toxicity to dental stem cells needs to be considered in clinical application.Keywords: Dental stem cells, Sodium hypochlorite, Viability, Proliferation, Differentiatio

Applications of various range shifters for proton pencil beam scanning radiotherapy

Background A range pull-back device, such as a machine-related range shifter (MRS) or a universal patient-related range shifter (UPRS), is needed in pencil beam scanning technique to treat shallow tumors. Methods Three UPRS made by QFix (Avondale, PA, USA) allow treating targets across the body: U-shaped bolus (UB), anterior lateral bolus (ALB), and couch top bolus. Head-and-neck (HN) patients who used the UPRS were tested. The in-air spot sizes were measured and compared in this study at air gaps: 6 cm, 16 cm, and 26 cm. Measurements were performed in a solid water phantom using a single-field optimization pencil beam scanning field with the ALB placed at 0, 10, and 20 cm air gaps. The two-dimensional dose maps at the middle of the spread-out Bragg peak were measured using ion chamber array MatriXX PT (IBA-Dosimetry, Schwarzenbruck, Germany) located at isocenter and compared with the treatment planning system. Results A UPRS can be consistently placed close to the patient and maintains a relatively small spot size resulting in improved dose distributions. However, when a UPRS is non-removable (e.g. thick couch top), the quality of volumetric imaging is degraded due to their high Z material construction, hindering the value of Image-Guided Radiation Therapy (IGRT). Limitations of using UPRS with small air gaps include reduced couch weight limit, potential collision with patient or immobilization devices, and challenges using non-coplanar fields with certain UPRS. Our experience showed the combination of a U-shaped bolus exclusively for an HN target and an MRS as the complimentary device for head-and-neck targets as well as for all other treatment sites may be ideal to preserve the dosimetric advantages of pencil beam scanning proton treatments across the body. Conclusion We have described how to implement UPRS and MRS for various clinical indications using the PBS technique, and comprehensively reviewed the advantage and disadvantages of UPRS and MRS. We recommend the removable UB only to be employed for the brain and HN treatments while an automated MRS is used for all proton beams that require RS but not convenient or feasible to use UB

Three-perspective energy-carbon nexus analysis for developing China's policies of CO2-emission mitigation

Energy usage and CO2 emission have intimate and inseparable linkages. The growth of energy usage causes an increase in CO2 emissions, which will in turn constrain the related energy policies and challenge the energy-system stability. It is essential to quantify China's CO2 emission inventories embodied in production-driven, demand-driven and supply-driven chains considering different energy types. A Three-Perspective Energy-Carbon Nexus model is developed to facilitate comprehensive CO2 emission-reduction analysis in China. The model incorporates environmental input-output analysis and ecological network analysis within a general framework to clarify the relationships among provinces in terms of the production-based, consumption-based and income-based accountings. A new indicator, indirect emission dominant factor, is for the first time examined to evaluate the dominant capabilities of indirect emissions. It is discovered that the emissions triggered by the demand-side are not sensitive to energy types. Furthermore, the changes of integral flow control intensity in each province are insignificant from consumption-based and income-based perspectives. Final demand contributes 80% of consumption-based emissions and gross value-added creation leads to a total of 82% income-based CO2 emissions in China in 2012. When controlling emissions from multiple perspectives, traditional methods may not be effective since they do not consider the forms of emissions; some methods (e.g., product allocation) are not suitable for suppressing indirect emissions. Moreover, the prosperity of developed regions (e.g. Guangdong) highly rely on support from underdeveloped regions (e.g. Inner Mongolia). Some underdeveloped provinces are receptors of CO2, while the developed ones are emitting CO2 to the system without assuming their emission-reduction responsibilities. In addition, secondary energy consumptions in developed regions are conducive in increasing their emission contributions to the system. In this research, an innovative perspective is initiated to disclose the energy-carbon interconnections across Chinese provinces. The obtained findings could help support the formulation of China's CO2 emission-reduction policies

Systematic and Dramatic Tuning on Gas Sorption Performance in Heterometallic Metal–Organic Frameworks

Despite their having much greater potential for compositional and structural diversity, heterometallic metal–organic frameworks (MOFs) reported so far have lagged far behind their homometallic counterparts in terms of CO₂ uptake performance. Now the power of heterometallic MOFs is in full display, as shown by a series of new materials (denoted CPM-200s) with superior CO₂ uptake capacity (up to 207.6 cm³/g at 273 K and 1 bar), close to the all-time record set by MOF-74-Mg. The isosteric heat of adsorption can also be tuned from −16.4 kJ/mol for CPM-200-Sc/Mg to −79.6 kJ/mol for CPM-200-V/Mg. The latter value is the highest reported for MOFs with Lewis acid sites. Some members of the CPM-200s family consist of combinations of metal ions (e.g., Mg/Ga, Mg/Fe, Mg/V, Mg/Sc) that have never been shown to coexist in any known crystalline porous materials. Such previously unseen combinations become reality through a cooperative crystallization process, which leads to the most intimate form of integration between even highly dissimilar metals, such as Mg²⁺ and V³⁺. The synergistic effects of heterometals bestow CPM-200s with the highest CO₂ uptake capacity among known heterometallic MOFs and place them in striking distance of the all-time CO₂ uptake record

Systematic and Dramatic Tuning on Gas Sorption Performance in Heterometallic Metal–Organic Frameworks

Despite their having much greater potential for compositional and structural diversity, heterometallic metal–organic frameworks (MOFs) reported so far have lagged far behind their homometallic counterparts in terms of CO₂ uptake performance. Now the power of heterometallic MOFs is in full display, as shown by a series of new materials (denoted CPM-200s) with superior CO₂ uptake capacity (up to 207.6 cm³/g at 273 K and 1 bar), close to the all-time record set by MOF-74-Mg. The isosteric heat of adsorption can also be tuned from −16.4 kJ/mol for CPM-200-Sc/Mg to −79.6 kJ/mol for CPM-200-V/Mg. The latter value is the highest reported for MOFs with Lewis acid sites. Some members of the CPM-200s family consist of combinations of metal ions (e.g., Mg/Ga, Mg/Fe, Mg/V, Mg/Sc) that have never been shown to coexist in any known crystalline porous materials. Such previously unseen combinations become reality through a cooperative crystallization process, which leads to the most intimate form of integration between even highly dissimilar metals, such as Mg²⁺ and V³⁺. The synergistic effects of heterometals bestow CPM-200s with the highest CO₂ uptake capacity among known heterometallic MOFs and place them in striking distance of the all-time CO₂ uptake record

Systematic and Dramatic Tuning on Gas Sorption Performance in Heterometallic Metal–Organic Frameworks

Despite their having much greater potential for compositional and structural diversity, heterometallic metal–organic frameworks (MOFs) reported so far have lagged far behind their homometallic counterparts in terms of CO₂ uptake performance. Now the power of heterometallic MOFs is in full display, as shown by a series of new materials (denoted CPM-200s) with superior CO₂ uptake capacity (up to 207.6 cm³/g at 273 K and 1 bar), close to the all-time record set by MOF-74-Mg. The isosteric heat of adsorption can also be tuned from −16.4 kJ/mol for CPM-200-Sc/Mg to −79.6 kJ/mol for CPM-200-V/Mg. The latter value is the highest reported for MOFs with Lewis acid sites. Some members of the CPM-200s family consist of combinations of metal ions (e.g., Mg/Ga, Mg/Fe, Mg/V, Mg/Sc) that have never been shown to coexist in any known crystalline porous materials. Such previously unseen combinations become reality through a cooperative crystallization process, which leads to the most intimate form of integration between even highly dissimilar metals, such as Mg²⁺ and V³⁺. The synergistic effects of heterometals bestow CPM-200s with the highest CO₂ uptake capacity among known heterometallic MOFs and place them in striking distance of the all-time CO₂ uptake record

From Hemoglobin to Porous N–S–Fe-Doped Carbon for Efficient Oxygen Electroreduction

Nitrogen–sulfur–iron-doped porous carbon material with high surface area (1026 m² g^–1) and large pore size is synthesized by the pyrolysis of hemoglobin, an abundant and inexpensive natural compound, with mesoporous silica foam (MS) as a template and thiocarbamide (TCA) as an additional sulfur source in an argon atmosphere. Our results indicated that as compared to the commercial 20% Pt/C catalyst, the synthesized catalyst exhibits not only higher current density and stability but also higher tolerance to crossover chemicals. More importantly, the synthetic method is simple and inexpensive

Time-Course Transcriptome Analysis of the Lungs of Mice Challenged with Aerosols of Methicillin-Resistant <i>Staphylococcus aureus</i> USA300 Clone Reveals Inflammatory Balance

USA300, a dominant clone of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA), is circulating globally and can cause necrotizing pneumonia with high morbidity and mortality. To further reveal the host anti-MRSA infection immune response, we established a mouse model of acute primary MRSA pneumonia challenged with aerosols of the USA300 clone. A time-course transcriptome analysis of the lungs collected at 0, 12, 24, 48 and 96 h post-infection (hpi) was conducted using RNA sequencing (RNA-seq) and multiple bioinformatic analysis methods. The change trend of histopathology and five innate immune cell (neutrophils, mononuclear cells, eosinophils, macrophages, DC cells) proportions in the lungs after infection was also examined. We observed a distinct acute pulmonary recovery process. A rapid initiation period of inflammation was present at 12 hpi, during which the IL-17 pathway dominantly mediated inflammation and immune defense. The main stages of host inflammatory response occurred at 24 and 48 hpi, and the regulation of interferon activation and macrophage polarization played an important role in the control of inflammatory balance at this stage. At 96 hpi, cellular proliferation processes associated with host repair were observed, as well as adaptive immunity and complement system responses involving C1q molecules. More importantly, the data provide new insight into and identify potential functional genes involved in the checks and balances occurring between host anti-inflammatory and proinflammatory responses. To the best of our knowledge, this is the first study to investigate transcriptional responses throughout the inflammatory recovery process in the lungs after MRSA infection. Our study uncovers valuable research targets for key regulatory mechanisms underlying the pathogenesis of MRSA lung infections, which may help to develop novel treatment strategies for MRSA pneumonia

Time-Course Transcriptome Analysis of the Lungs of Mice Challenged with Aerosols of Methicillin-Resistant Staphylococcus aureus USA300 Clone Reveals Inflammatory Balance

USA300, a dominant clone of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA), is circulating globally and can cause necrotizing pneumonia with high morbidity and mortality. To further reveal the host anti-MRSA infection immune response, we established a mouse model of acute primary MRSA pneumonia challenged with aerosols of the USA300 clone. A time-course transcriptome analysis of the lungs collected at 0, 12, 24, 48 and 96 h post-infection (hpi) was conducted using RNA sequencing (RNA-seq) and multiple bioinformatic analysis methods. The change trend of histopathology and five innate immune cell (neutrophils, mononuclear cells, eosinophils, macrophages, DC cells) proportions in the lungs after infection was also examined. We observed a distinct acute pulmonary recovery process. A rapid initiation period of inflammation was present at 12 hpi, during which the IL-17 pathway dominantly mediated inflammation and immune defense. The main stages of host inflammatory response occurred at 24 and 48 hpi, and the regulation of interferon activation and macrophage polarization played an important role in the control of inflammatory balance at this stage. At 96 hpi, cellular proliferation processes associated with host repair were observed, as well as adaptive immunity and complement system responses involving C1q molecules. More importantly, the data provide new insight into and identify potential functional genes involved in the checks and balances occurring between host anti-inflammatory and proinflammatory responses. To the best of our knowledge, this is the first study to investigate transcriptional responses throughout the inflammatory recovery process in the lungs after MRSA infection. Our study uncovers valuable research targets for key regulatory mechanisms underlying the pathogenesis of MRSA lung infections, which may help to develop novel treatment strategies for MRSA pneumonia