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Nitric oxide (NO) binds to soluble guanylyl cyclase (sGC), activates it in a reduced oxidized heme iron state, and generates cyclic Guanosine Monophosphate (cGMP), which results in vasodilatation and inhibition of osteoclast activity. In inflammation, sGC is oxidized and becomes insensitive to NO. NO- and heme-independent activation of sGC requires protein expression of the α1- and β1-subunits. Inflammation of the periodontium induces the resorption of cementum by cementoclasts and the resorption of the alveolar bone by osteoclasts, which can lead to tooth loss. As the presence of sGC in cementoclasts is unknown, we investigated the α1- and β1-subunits of sGC in cementoclasts of healthy and inflamed human periodontium using double immunostaining for CD68 and cathepsin K and compared the findings with those of osteoclasts from the same sections. In comparison to cementoclasts in the healthy periodontium, cementoclasts under inflammatory conditions showed a decreased staining intensity for both α1- and β1-subunits of sGC, indicating reduced protein expression of these subunits. Therefore, pharmacological activation of sGC in inflamed periodontal tissues in an NO- and heme-independent manner could be considered as a new treatment strategy to inhibit cementum resorption.  相似文献   
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Abstract

Biosorption has been shown in the literature to be effective in the removal of dye from aqueous solution. To be fully useful, a desorption process is necessary, which has a direct impact on the process costs. The aim of this work was to evaluate the desorption of the azo dye Acid Yellow 23 adsorbed in a biosorbent obtained from Bombyx mori cocoons. Temperature and pH media were evaluated through a mixed two- and three-level design, using NaOH as desorbing agent. Kinetic desorption was also obtained at the optimized condition. The statistical evaluation of the experimental design showed that the pH has almost two times more influence on the dye desorption than the temperature, with only the linear parameters being statistically significant. Among four kinetic desorption models adjusted to the experimental data, the proposed n-order model was statistically determined as the best representation of the experimental data.  相似文献   
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Eggs of T. bisselliella were exposed to sub-zero temperatures at a cooling rate of 2°C/h to a minimum of −20°C. Observed mortality was closely approximated by predictions based on an adapted fixed temperature model. The eggs showed no acclimation during cooling. In combination with thermal conductivity models the mortality model provides a simple method to predict exposure times required to reach the desired level of mortality in the cold disinfestation treatment of a commodity or item. With large items, minimum dimension 50 cm, it is predicted that disinfestation will be achieved before the centre has reached −20°C.  相似文献   
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The Clean Development Mechanism established under the Kyoto Protocol allows investors in the developed world to invest in the developing world in return for emission credits. The CDM has two goals—to contribute to the reduction of emissions in the developed countries, and to promote sustainable development in the developing country. The objective of this paper is to analyze the project portfolio of 400 published CDM projects in the sector “waste handling and disposal” according to their project and technology characteristics.  相似文献   
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This study examined the current governance system for Lake Buhi, Philippines. It describes stakeholder patterns of decision‐making, their roles in the decision‐making process based on their legal mandates, the manner of interactions, the sources of conflict and how these various issues are currently resolved. Stakeholders represent diverse interests, including irrigation, hydropower generation, fishery management and navigation. This study uses data generated from ten key informant interviews of the different stakeholders, information from five round table discussions, and secondary data and reports of various agencies. The results indicate that Lake Buhi and its watershed present classic man‐in‐nature governance challenges. The interplay of internal and external uncertainties regarding multiple uses results in a complex system that is difficult to effectively manage. Climate‐related hazards aggravate the pressures from activities within the lake watershed, complicating water allocation issues. The institutional arrangements that have emerged to address these challenges, however, appear to be fraught with overlaps, fragmentation and a lack of communication. It is thought these deficiencies could be addressed by establishing a lake basin council with representation from all the involved organizations, as well as any stakeholder groups not represented by organizations. The system of governance over the lake must address issues concerning water uses and access to the resource. The capacity of the organizations to participate in such an arrangement is weak, however, and capacity building is needed. The availability and sharing of data and information among stakeholders are also weak and must be strengthened if the work of the lake basin council is to be based on the best available information.  相似文献   
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Rubber goods usually require a combination of properties that cannot be provided by one elastomer only and then two or more polymer components have to be mixed to meet specific requirements. In such cases, the additives normally employed in rubber formulations are unevenly distributed, depending on the affinity of each compound to each polymeric phase. Thus, the dispersion of each one of these ingredients in the different rubbers will influence the rate and degree of vulcanization and, in consequence, the performance of the final composite. In this work, natural rubber (NR) and styrene butadiene rubber (SBR) were mixed in a 1 : 1 ratio. The compositions were obtained according to ASTM D 3182, by using four different preparative modes for the incorporation of the additives. After vulcanization, morphological, and dynamic mechanical thermal analysis, tensile strength, hardness, and tear resistance of each composition were investigated. The results show that the best properties were found when the NR/SBR mixture was prepared in such a way as to favor the vulcanization of the SBR phase while preserving the NR phase from excessive vulcanization. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 483–489, 2004  相似文献   
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