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Kidney transplantation is the most effective treatment for end-stage renal disease, but is limited by the increasing shortage of deceased and living human donor kidneys. Xenotransplantation using pig organs provides the possibility to resolve the issue of organ supply shortage and is regarded as the next great medical revolution. In the past five years, there have been sequential advances toward the prolongation of life-supporting pig kidney xenograft survival in non-human primates, with the longest survival being 499 days. This progress is due to the growing availability of pigs with multi-layered genetic modifications to overcome the pathobiological barriers and the application of a costimulation blockade-based immunosuppressive regimen. These encouraging results bring the hope to initiate the clinical trials of pig kidney transplantation in the near future. In this review, we summarized the latest advances regarding pig kidney xenotransplantation in preclinical models to provide a basis for future investigation and potential clinical translation.

Prevention of ATP binding cassette transporter A1 (ABCA1)-dependent cholesterol efflux leads to lipid accumulation in macrophages and atherosclerosis development. C1q tumor necrosis factor-related protein 1 (CTRP1), a conserved paralog of adiponectin, has been shown to aggravate atherosclerosis via its pro-inflammatory property. However, very little is known about its effects on ABCA1 expression and macrophage lipid accumulation. In the current studies, we found that CTRP1 down-regulated ABCA1 expression, inhibited cholesterol efflux to apoA-I and promoted lipid accumulation in THP-1 macrophage-derived foam cells. Forkhead box O1 (FoxO1), a transcriptional repressor of ABCA1, was identified as a direct target of miR-424-5p. Mechanistically, CTRP1 attenuated miR-424-5p levels and then augmented FoxO1 expression in the nucleus, which led to down-regulation of ABCA1 expression and inhibition of cholesterol efflux. In conclusion, these findings suggest that CTRP1 restrains cholesterol efflux and facilitates macrophage lipid accumulation through the miR-424-5p/FoxO1/ABCA1 signaling pathway, thereby providing a novel mechanistical insight into its pro-atherosclerotic action. This article is protected by copyright. All rights reserved.

Kcnq1 overlapping transcript 1 (kcnq1ot1), an imprinted antisense lncRNA in the kcnq1 locus, acts as a potential contributor to cardiovascular disease, but its role in atherosclerosis remains unknown. The aim of this study was to explore the effects of kcnq1ot1 on atherogenesis and the underlying mechanism. Our results showed that kcnq1ot1 expression was significantly increased in mouse aorta with atherosclerosis and lipid-loaded macrophages. Lentivirus-mediated kcnq1ot1 overexpression markedly increased atherosclerotic plaque area and decreased plasma HDL-C levels and RCT efficiency in apoE−/− mice fed a Western diet. Upregulation of kcnq1ot1 also reduced the expression of miR-452-3p and ABCA1 but increased HDAC3 levels in mouse aorta and THP-1 macrophages. Accordingly, kcnq1ot1 overexpression inhibited cholesterol efflux and promoted lipid accumulation in THP-1 macrophages. In contrast, kcnq1ot1 knockdown protected against atherosclerosis in apoE−/− mice and suppressed lipid accumulation in THP-1 macrophages. Mechanistically, kcnq1ot1 enhanced HDAC3 expression by competitively binding to miR-452-3p, thereby inhibiting ABCA1 expression and subsequent cholesterol efflux. Taken together, these findings suggest that kcnq1ot1 promotes macrophage lipid accumulation and accelerates the development of atherosclerosis through the miR-452-3p/HDAC3/ABCA1 pathway.

C1q tumor necrosis factor-related protein 12 (CTRP12), a conserved paralog of adiponectin, is closely associated with cardiovascular disease. However, little is known about its role in atherogenesis. The aim of this study was to examine the influence of CTRP12 on atherosclerosis and explore the underlying mechanisms. Our results showed that lentivirus-mediated CTRP12 overexpression inhibited lipid accumulation and inflammatory response in lipid-laden macrophages. Mechanistically, CTRP12 decreased miR-155-5p levels and then increased its target gene liver X receptor α (LXRα) expression, which increased ATP binding cassette transporter A1 (ABCA1)- and ABCG1-dependent cholesterol efflux and promoted macrophage polarization to the M2 phenotype. Injection of lentiviral vector expressing CTRP12 decreased atherosclerotic lesion area, elevated plasma high-density lipoprotein cholesterol levels, promoted reverse cholesterol transport (RCT), and alleviated inflammatory response in apolipoprotein E-deficient (apoE−/−) mice fed a Western diet. Similar to the findings of in vitro experiments, CTRP12 overexpression diminished miR-155-5p levels but increased LXRα, ABCA1, and ABCG1 expression in the aortas of apoE−/− mice. Taken together, these results suggest that CTRP12 protects against atherosclerosis by enhancing RCT efficiency and mitigating vascular inflammation via the miR-155-5p/LXRα pathway. Stimulating CTRP12 production could be a novel approach for reducing atherosclerosis.

Biochanin A (BCA), a dietary isoflavone extracted from red clover and cabbage, has been shown to antagonize hypertension and myocardial ischemia/reperfusion injury. However, very little is known about its role in atherogenesis. The aim of this study was to observe the effects of BCA on atherosclerosis and explore the underlying mechanisms. Our results showed that administration of BCA promoted reverse cholesterol transport (RCT), improved plasma lipid profile, and decreased serum proinflammatory cytokine levels and atherosclerotic lesion area in apoE-/- mice fed a Western diet. In THP-1 macrophage-derived foam cells, treatment with BCA upregulated ATP-binding cassette (ABC) transporter A1 (ABCA1) and ABCG1 expression and facilitated subsequent cholesterol efflux and diminished intracellular cholesterol contents by activating the peroxisome proliferator-activated receptor γ (PPARγ)/liver X receptor α (LXRα) and PPARγ/heme oxygenase 1 (HO-1) pathways. BCA also activated these two signaling pathways to inhibit the secretion of proinflammatory cytokines. Taken together, these findings suggest that BCA is protective against atherosclerosis by inhibiting lipid accumulation and inflammatory response through the PPARγ/LXRα and PPARγ/HO-1 pathways. BCA may be an attractive drug for the prevention and treatment of atherosclerotic cardiovascular disease.

The microwave-assisted CH4decomposition over a pyrolysis residue of sewage sludge (PRSS), which acted as a microwave receptor and a low-cost catalyst without further activation, was investigated in a multimode microwave reactor. The results indicated that the microwave heating of PRSS is heavily influenced by atmosphere. The PRSS temperature in CH4, N2and H2atmosphere follow the sequence ofTCH4

NO reduction by iron was conducted in a one-dimensional ceramic tubular reactor at 300 - 1100 °C in N2and simulated flue gas atmosphere with 0.4% methane and 0.01%~0.04% SO2. The evolution of metallic iron was investigated by X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and energy dispersive spectrum (EDS) methods. The results showed that SO2did not place negative effect on NO reduction by iron. XRD patterns showed that FeS was formed when there was SO2in the flue gas. The iron oxides were FeO and Fe3O4when methane was not and was used as reducing agent respectively. Rough and raised surface making up of a series of round smooth juts was formed over the iron surface after reaction with NO in N2atmosphere when there was 0.04% SO2. Porous surface consisting serried particles was formed when methane was used as reductant. White attachments were found locally on the iron surface when SO2existed in the flue gas, which was proved by EDS analysis to be FeS.

NO reduction by iron was conducted in a one-dimensional ceramic tubular reactor at 300 - 1100 °C with simulated flue gas of 0.05% NO in N2base. The evolution of metallic iron was investigated by X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) methods. The effect of reducing gases including CO and CH4was analyzed on the redox of iron. Results showed that metallic iron was oxidized to its oxides after the reaction with NO. In N2atmosphere, Fe3O4was the major iron oxide at 550 °C and Fe2O3was the major iron oxide at 1100 °C. SEM image of the iron sample surface showed that the iron surface was smooth and dense after the iron reduced NO at 550 °C, however, the iron surface became porous after the iron reduced NO at 1100 °C. Reducing gas CO could reduce iron oxides to metallic iron. XRD result showed that a little FeO was found but metallic iron was still the dominant component of the iron sample after the reaction with NO in CO atmosphere. CO was not effective to maintain a durable NO reduction efficiency in simulated flue gas atmosphere while CH4was very effective. XRD result of the iron sample after the 100 hours durable test at 1050°C when 1.17% CH4was added into the simulated flue gas showed that the iron was not fully oxidized during the durable reaction.

Microwave catalytic pyrolysis of sewage sludge were conducted on a single mode microwave reactor. The effects of CaO and steam on hydrogen-rich gas formation characteristics were analyzed. The results indicated that the CaO can improve the formation of H2and CO. When CaO in sewage sludge increased from 0 to 0.75 g/(g dried sludge), the H2and CO concentration increased from 62 vol.% to 77 vol.%, while CH4and CO2concentrations decreased from 28 vol.% to 9 vol.%. The steam can also improve the formation of H2and CO, with 1.59 g/min of the steam flowrate, the H2and CO concentration increased to the maximum of 81 vol.%, and the CH4and CO2concentration decreased to the minimum of 16 vol.%. When the steam gasification was coupled with the CaO catalyzing, the H2concentration can reach to 61 vol.%, which was 79.3% higher than the experimental conditions absent of steam and CaO.

Microwave pyrolysis of sewage sludge was conducted in a single-mode microwave oven. The influencing effects of experimental factors, including particle size and moisture content of sewage sludge, pyrolysis temperature, and shape of microwave adsorber, on concentration of pyrolysis gas products were studied. The results indicated that with the decrease of particle size, the H2 concentration increased from 31 vol.% to 34 vol.%, and CO concentration increased from 17 vol.% to 22 vol.%. When the moisture content of sewage sludge increased from 0 to 83 wt.%, the H2 concentration increased from 32 vol.% to 42 vol.%, and the CO concentration increased from 20 vol.% to 31 vol.%. Compared with microwave adsorber in powder phase, the microwave adsorber in fixed structure can transform more volatile compounds to uncondensable gas, and the concentrations of H2 and CO were also slightly increased.

Reburning is effective to control NO emission. The paper presents a short review on recent research on catalysis reduction of NO and HCN/NH3by some metal and their oxides during reburning. The major difficulties that limit NO reduction efficiency by reburning involve the re-oxidation of the intermediate products during reburning, HCN/NH3and char nitrogen to NO. So far, results showed that Fe2O3could reduce the formation of HCN/NH3after reburning and metallic iron could directly reduce NO to N2. Temperature and co-existing gases influenced the catalysis performance of Fe and its oxides. Detailed mechanism and kinetics of the reactions should be further investigated.

A binocular point matching method using affine transformation is presented in this paper to deal with matching ambiguities. The epipolar geometry is used to determine all the possible matching pairs to form an initial correspondence data set. Then, an affine registration model with four parameters that is invariant to scaling, rotation and translation is built using the Random Sample Consensus (RANSAC) method to describe the coordinate transformation between the two members of correspondences. Finally, correspondences are picked out using minimal nearest neighbor distances based on the geometric similarity between the right image points and the transformed left ones. The proposed method is applied to measure the profile of a 3.5m parabolic reflector of an inflatable antenna and proved to be able to handle the extra or missing point matching problems coursed by occlusion and sheltering. Satisfactory results are obtained with high correct rate for matching most image pairs despite the significantly different viewpoints, which indicates its validity and application feasibility in automatic stereovision measurement field.

Contact drying experiments were carried out in a Nara-type paddle dryer to study the drying kinetics of sewage sludge in the presence of air. In order to have a better understanding of the sewage sludge drying mechanism, a penetration model developed by Tsotsas and Schlunder is used to simulate the drying kinetics of the pasty, lumpy and granular phase which the sludge experiences during the drying process. The pasty phase is assumed to be a saturated particulate phase, and the granular phase is considered as a mono-dispersed particulate phase whose diameter was experimentally determined. In the lumpy phase, a sludge wall sticking still to the paddle–shaft surface was formed, and the heat transfer resistance from the sludge wall is considered during the model calculation. The influence of the drying parameters (temperature, stirrer speed and air flowrate) on the drying process is investigated experimentally and theoretically. The result indicates that the penetration theory is able to describe the sludge drying kinetics of the three distinct phases. Experimental and calculated drying kinetics are in satisfactory agreement for different drying parameters.

The emission and contact drying kinetics of the paper mill sludge (PMS) were studied through experiments carried out in a paddle dryer. To get a better understanding of its drying mechanism, a penetration model developed by Tsotsas and Schlunder (1986) was used to simulate the drying kinetics of the PMS. The result indicated that this kinetics could be divided into three phases: pasty, lumpy and granular phases, and could be successfully simulated by the penetration model as the related sludge parameters were integrated into the model. The emission rate curves of the volatile compounds (VCs) were interrelated to the drying rate curve of the PMS, especially for volatile fatty acids (VFAs) and ammonia in this study.

Agitated contact drying experiments were carried out in a cylindrical lab-scale paddle dryer to study the drying kinetics of sewage sludge under partial vacuum conditions. To explore the drying mechanisms, the penetration model for vacuum contact drying of agitated particulate materials, developed by Schlunder and Mollekopf, was applied to simulate the experimental results. The influence of the drying parameters (system pressure, heating temperature, stirrer speed, and dryer load) on the drying kinetics was studied both experimentally and theoretically. The results indicate that pressure and temperature significantly influence the drying rates of sewage sludge, whereas stirring speed and dryer load have no obvious effects on drying rates in the examined range. The experimental and simulated drying rates were in acceptable agreement as long as the temperature difference between dryer and sludge was small. A crust is likely to form on the dryer surface, however, when the temperature difference becomes large...

This paper presents a method to measure the deformation of large deployable mesh microwave antenna by using the photogrammetric technology. Because the mesh reflector surface is controlled by 79 nodes, measuring 3D coordinates of these nodes accurately is the key to test the deformation of antenna. The technique of camera calibration, the matching method of the image points, and the solution of measuring 3D points are introduced in this paper. The experimental data is also provided. This paper proposes a method to calculate the spatial coordinates of microwave antenna nodes by using the bundle adjustment with distance constraints. This method is capable of correcting the influences of the lens distortion and improving system measurement accuracy. In reference to the fact that the surface of this antenna is controlled by 79 nodes, and the design parameter of these nodes is already known, a method based on digital surface model constrain is used to solve the image points matching problem. This method efficiently simplifies the computation procedure and shortens the measurement time.

Yong-Hong Yi1, Wen-Chao Guo1, Wei-Wen Sun1, Tao Su1, Han Lin1, Sheng-Qiang Chen1, Wen-Yi Deng1, Wei Zhou2, Wei-Ping Liao11Department of Neurology, Institute of Neurosciences and the Second Affiliated Hospital, 2Department of Neonatology, Affiliated Guangzhou Children’s Hospital, Guangzhou Medical College, Guangzhou, Guangdong Province, P.R. ChinaAbstract: Lamotrigine (LTG), an antiepileptic drug, has been shown to be able to improve cerebral ischemic damage by limiting the presynaptic release of glutamate. The present study investigated further the neuroprotective effect of LTG on hypoxic-ischemic brain damage (HIBD) in neonatal rats and its relations to administration time and doses. The HIBD model was produced in 7-days old SD rats by left common carotid artery ligation followed by 2 h hypoxic exposure (8% oxygen). LTG was administered intraperitoneally with the doses of 5, 10, 20, and 40 mg/kg 3 h after operation and the dose of 20 mg/kg 1 h before and 3 h, 6 h after operation. Blood and brain were sampled 24 h after operation. Nissl staining, terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL), and neuron-specific enolase (NSE) immunohistochemical staining were used for morphological studies. Water content in left cortex and NSE concentration in serum were determined. LTG significantly reduced water content in the cerebral cortex, as well as the number of TUNEL staining neurons in the dentate gyrus and cortex in hypoxic-ischemia (HI) model. Furthermore, LTG significantly decreased the NSE level in serum and increased the number of NSE staining neurons in the cortex. These effects, except that on water content, were dose-dependent and were more remarkable in the pre-treated group than in the post-treated groups. These results demonstrate that LTG may have a neuroprotective effect on acute HIBD in neonates. The effect is more prominent when administrated with higher doses and before HI.Keywords: hypoxic-ischemic brain damage, lamotrigine, neonatal rat, neuroprotection

The inflatable space antenna is gradually used in various spacecrafts because it is portable and foldaway. It is usually made of thin-film materials and has a flexible surface, so that measuring force is not tolerable in measurement process. Close-range photogrammetry is considered as an optimal solution because of its advantages of non-contact operation and fast data acquisition. To improve measuring precision, a method combining bundle adjustment algorithm and the distance constraint is presented in the paper. Two experiments under different conditions are accomplished and experiment results are compared. One experiment is completed with the distance constraint and another without. The experiment results are compared by two parameters: tightness and residuals. The measured object is an inflatable antenna with a 3.5-m diameter.

Pre-dried sewage sludge with high sulfur content was combusted in an electrically heated lab-scale fluidized-bed incinerator. The emission characteristics of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polycyclic aromatic hydrocarbons (PAHs) were studied. Coal and calcium oxide (CaO) were added during the sewage sludge combustion tests to optimize combustion conditions and control SO2 emission. The results indicated that the flue gases emitted during mono-combustion of sewage sludge were characterized by relatively high concentrations of SO2, NOx and organic pollutants, due to the high sulfur, nitrogen, and volatile matter content of sewage sludge. The total 16 USEPA priority PAHs and 2,3,7,8-substituted PCDD/Fs produced from sewage sludge combustion were found to be 106.14 microg/m3 and 8955.93 pg/m3 in the flue gas, respectively. In the case of co-combustion with coal (m(sludge)/m(coal) = 1:1), the 16 PAHs and 2,3,7,8-substituted PCDD/Fs concentrations were markedly lower than those found during mono-combustion of sewage sludge. During co-combustion, a suppressant effect of CaO on PCDD/Fs formation was observed.

The emission characteristics of volatile compounds (VCs) during municipal sewage sludge (MSS) and paper mill sludge (PMS) drying process were investigated through experiments conducted on a lab-scale tubular drying furnace and a pilot-scale paddle dryer, respectively. The result indicated that five kinds of VCs, i.e. CO(2), NH(3), C(7)H(16) (n-heptane), volatile fatty acids (VFAs) and CH(4) were emitted during the drying process. It was found that the NH(3) and CO(2) were the primary compound released from the MSS drying process. In the case of the PMS, the VFAs and CO(2) were the main compounds released. The temperature and water content of sludge had great effects on the emission rates of NH(3), C(7)H(16), CO(2) and VFAs. The pH and chemical oxygen demand (COD) of condensate from the paddle dryer were also studied. It showed that pH and COD of condensate from MSS were much higher than that from the PMS, and that the higher COD value of the MSS condensate interrelated to the higher ammonium and sulfur content of it.