Search

Acute respiratory distress syndrome (ARDS) is greatly threatening human health with high morbidity and mortality. The pathogenesis of ARDS is closely related to the inflammatory response in patients. The micro-ribonucleic acid (miR)-155/nuclear factor-κB (NF-κB) signaling pathway is crucial in regulating the expression of inflammation-related genes. Therefore, the influences of miR-155/NF-κB signaling pathway on inflammatory factors in ARDS in neonatal pigs were explored in this study.The model of ARDS in neonatal pigs was established first. The expression levels of miR-155, NF-κB-related proteins, and inflammatory factors in model group and control group were detected, and their differences were compared. Moreover, after treatment with the miR-155/NF-κB signaling pathway inhibitor, the changes of the inflammatory factors expression in ARDS neonatal pigs were observed at different time points.In the model group, the levels of miR-155 and NF-κB-related proteins were significantly increased, and the levels of inflammatory factors, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-6, were also increased synchronously. However, the levels of IL-4 and IL-10 declined significantly. In addition, it was proved that after treatment with the inhibitor in model group the mRNA expressions of miR-155/NF-κB signaling pathway-related proteins were significantly inhibited, and the levels of IL-1β, TNF-α, and IL-6 were also significantly inhibited (p0.05). The levels of IL-4 and IL-10 remarkably rose after treatment with the inhibitor for 24 h (p0.05).The miR-155/NF-κB signaling pathway influenced the changes of inflammatory factors in ARDS in neonatal pigs, which might be a potential target for eliminating the inflammatory response after ARDS in neonatal pigs.

Muon-induced neutrons are one of the major backgrounds to various underground experiments, such as dark matter searches, low-energy neutrino oscillation experiments and neutrino-less double beta-decay experiments. Previous experiments on the underground production rate of muon-induced neutrons were mostly carried out either at shallow sites or at very deep sites. The Aberdeen Tunnel experiment aims to measure the neutron production rate at a moderate depth of 611 meters water equivalent. Our apparatus comprises of six layers of plastic-scintillator hodoscopes for tracking the incident cosmic-ray muons, and 760 L of gadolinium-doped liquid-scintillator for both neutron production and detection targets. In this paper, we describe the design and the performance of the apparatus. The preliminary result on the measurement of neutron production rate is also presented.

Background and Purpose Orexins have been demonstrated to play important roles in many physiological processes. However, it is not known how orexin A affects the activity of the hypoglossal motoneuron (HMN) and genioglossus (GG) muscle. Experimental Approach GG muscle electromyograms (GG-EMG) were recorded in anaesthetized adult rats after orexin A or orexin receptor antagonists were applied to the hypoglossal nucleus, and in adult rats in which orexin neurons were lesioned with the neurotoxin orexin-saporin (orexin-SAP). HMN membrane potential and firing were recorded from neonatal rat brain slices using whole-cell patch clamp after an infusion of orexin A or orexin receptor antagonists. Key Results Unilateral micro-injection of orexin A (50, 100 or 200 μM) into the hypoglossal nucleus significantly enhanced ipsilateral GG activity in adult rats. Orexin A (4, 20, 100 or 500 nM) depolarized the resting membrane potential and increased the firing rate of HMNs in a dose-dependent manner in the medullary slices of neonatal rats. Both SB 334867, a specific OX1 receptor antagonist and TCS OX2 29, a specific OX2 receptor antagonist not only blocked the depolarized membrane potential and the increased firing rate of HMNs by orexin A in the neonatal model but also attenuated GG-EMG in the adult model. A significant decrease in GG-EMG was observed in adult orexin neuron-lesioned rats compared with sham animals. Conclusion and Implications Orexin A activates OX1 and OX2 receptors within the hypoglossal motor pool and promotes GG activity, indicating that orexin A is involved in controlling respiratory motor activity.

Fe–Ni base superalloy GH4706 has been used for large size disc forgings of heavy duty gas turbines. In this paper, based on the change law of precipitation, influential effects of stabilisation time on precipitation behaviour and mechanical properties of GH4706 alloy were investigated. Results show that with prolongation of the stabilisation time, the morphologies of η phase changed from chain and rod-like to cellular, cluster and needle-shaped; meanwhile, large globular γ′ phase and rod-like γ″ phase gradually precipitated. Furthermore, the content of the η phase increased with increasing stabilisation time, and the precipitation free zone tended to be wider, owing to the reaction between the γ′ phase and the η phase. The room temperature and 650°C tensile strength and rupture life of the GH4706 alloy improved after stabilisation treatment at 845°C for 1–3 h.

An external electrostatic field treatment (EFT) was applied to GH4169 alloy with standard heating treatment. The internal friction and room temperature (RT) tensile test were conducted for both the electrostatic field treated and standard heating treated alloys in order to investigate the variations of microstructure and mechanical properties of the alloy with the EFT. The experimental results demonstrated that the EFT remarkably enhanced the formation of interstitial atoms and vacancies. During the tensile deformation at RT under the strain rate of 10−2 or 10−4 s−1, the dislocation slip could be evidently hindered by the large numbers of interstitial atoms in the matrix, contributing to a great increase in the yield and tensile strengths of the electrostatic field treated alloy. By EFT, the dislocation configuration of deformed alloy was primarily the single slip instead of the cross-slip in the standard heating treated alloy, resulting in the increasing of grain deformation capacity by more vaca...

Light-harvesting II complexes (LHCII) and photosystem II core complexes (PSIICC) were isolated from spinach (Spinacia oleracea L.) and reconstituted into phosphatidylcholine liposomes and, under heat stress, PSIICC-LHCII proteoliposomes were found to exhibit significantly higher oxygen evolution activity than PSIICC proteoliposomes lacking LHCII. In the presence of LHCII, the temperature of a 10-min heat stress that caused semi-inactivation of oxygen-evolving activity in these liposomes increased from 34 to ∼37°C and the total inactivation temperature increased from ∼50 to ∼60°C. Moreover, with heat stress, decreases in the absorbance and fluorescence spectra of PSIICC-LHCII proteoliposomes were smaller than in LHCII-lacking PSIICC proteoliposomes. These results demonstrated that reconstitution of PSII into liposomes with LHCII increased the antenna size and light harvesting cross-section of PSII and thus, under heat stress, enhanced PSII photochemical activity and thermal stability.

The geometrical optics ray-tracing approach is an effective and simple method of studying the radiative properties of rough surfaces. The conventional geometrical optics ray-tracing method does not consider the interference effect, and therefore limits its application. In this paper, the conventional geometrical optics ray-tracing method is updated by considering the effect of the interference. Two geometrical optics ray-tracing methods and a finite different time domain method are used to study the radiative properties of a one-dimensional random rough surface. By comparing the results of the different methods, the effect of interference is quantified and discussed under various conditions. The interference effect cannot be neglected for the case of strong roughness and oblique incidence. Compared with the conventional geometrical optics ray-tracing method, the improved geometrical optics ray-tracing method has a higher precision and wider application. The interaction between the surface roughness and mu...

Structured Abstract Objectives To investigate rapid palatal expansion (RPE)–induced metabolic changes in human dental pulp by measuring the expression and activity of aspartate aminotransferase (AST). Methods mRNA and protein levels of AST in human dental pulp were measured by quantitative real-time polymerase chain reaction and Western blot, respectively. Furthermore, the activity of AST was measured by a full automatic biochemical analyzer. Results AST mRNA and protein levels were found to be expressed in normal dental pulp. Moreover, the expression of AST was increased significantly after 14 days of RPE and then decreased at 1 month in retention. Three and 6 months after RPE, the AST expression level was gradually decreased to its baseline level. Similarly, AST activity was significantly elevated after 14 days of RPE, which was then down-regulated at 1 month in retention but was still kept at a higher level as compared with the control group. The enzymatic activity of AST was slowly decreased to its baseline level at 3 and 6 months in retention. Conclusions These results showed that significant reversible metabolic changes occurred in dental pulp during RPE, which revealed the high capacity of the pulp tissue for adaptation to this orthopedic method.

In this study, creep rupture in a bundle of slowly relaxing fibres was investigated. The intact fibre was assumed to exhibit linear elastic behaviour; however, its load did not drop to zero instantaneously after breaking but underwent a slow relaxation process, and thus, it introduced a time-dependent behaviour in the system, which was modelled by a Kelvin–Voigt element. Under the assumption of global load sharing for the redistribution of load, the analytical and simulated results showed the formation of two distinct regimes of the creep process depending on the value of the external load. For external loads greater than the critical load, the system suffered a macroscopic rupture in a finite time. However, for external loads smaller than the critical load, the system was characterized by an infinite lifetime. The critical load depended on the ratio of the elastic modulus between the intact and the failure elements, Eb/ E. It was observed that the time to rupture, tf, had a power-law divergence with an exponent −1/2 when the load approached the critical load from above. Moreover, the acoustic emission response was measured from the rate of breaking of fibres in the simulations.

This paper presents a method for estimating the vehicle side slip angle, which is considered as a significant signal in determining the vehicle stability region in vehicle stability control systems. The proposed method combines the model-based method and kinematics-based method. Side forces of the front and rear axles are provided as a weighted sum of directly calculated values from a lateral acceleration sensor and a yaw rate sensor and from a tire model according to the nonlinear factor, which is defined to identify the degree of nonlinearity of the vehicle state. Then, the side forces are fed to the extended Kalman filter, which is designed based on the single-track vehicle model associated with a tire model. The cornering stiffness identifier is introduced to compensate for tire force nonlinearities. A fuzzy-logic procedure is implemented to determine the nonlinear factor from the input variables: yaw rate deviation from the reference value and lateral acceleration. The proposed observer is compared with a model-based method and kinematics-based method. An 8 DOF vehicle model and Dugoff tire model are employed to simulate the vehicle state in MATLAB/SIMULINK. The simulation results shows that the proposed method is more accurate than the model-based method and kinematics-based method when the vehicle is subjected to severe maneuvers under different road conditions.

In this paper a sliding-mode yaw moment controller and fuzzy logic wheel slip controller are proposed to enhance vehicle stability in a split- μ manoeuvre. The proposed wheel slip controller shows good performance in improving vehicle handling in a braking manoeuvre. However, when a braking manoeuvre was conducted under the split- μ condition, the yaw moment generated by the asymmetric braking forces may cause the vehicle-handling stability to deteriorate. The sliding-mode yaw moment controller was introduced to regulate the wheel slip controller to improve the vehicle-handling performance. A target slip allocation algorithm was employed to coordinate the control conflict between the anti-lock braking system and vehicle stability control. First, the proposed control system was evaluated through pure computer simulation and a hardware in-the-loop simulation system. Then an experimental test was also introduced to verify the effectiveness of the proposed control system.

In the untransformed rice (WT) and transgenic rice with the PEPC and PPDK genes (CK) we determined activities of C4 photosynthetic enzymes, photosynthetic response to irradiance and temperature, the metabolic index of active oxygen, and the yield component factors. The activities of C4 photosynthetic enzymes in WT were very low, while those of corresponding enzymes in CK were highly observable. Moreover, after adenosine triphosphate (ATP) treatment, and under high irradiance and high temperature, the net photosynthetic rate of CK increased by 17 and 12 %, respectively, as compared to that achieved without ATP treatment. The resistance of CK against photo-oxidation was enhanced under these conditions, and CK yield increased by 15 %. ATP treatment enhanced the photosynthetic productivity of CK, thereby proving that ATP is the key factor in enhancing the photosynthetic capacity of transgenic rice with C4 gene. Our new technical approach can be used in breeding rice with high photosynthetic efficiency and high grain yield.

The influence of rare-earth elements on the microstructural features of rapidly solidified Al93.3-xFe4.3V0.7Si1.7Mmx(x=0, 0.5, 1.0, 3.0, 6.0) alloy was systematically studied by differential scanning calorimetry, X-ray diffraction, transmission electron microscopy and energy dispersive X-ray analysis. Experimental results show that there are different type of phase transformation depending on mischmetal (Mm) concentration. For Al87.3Fe4.3V0.7Si1.7Mm6.0 metallic glass, a shoulder was observed on the high-angle side of the main peak in the X-ray diffraction patterns due to quenched-in aluminium nuclei and a prepeak resulting from Mm–Mm pairs. By means of particle extraction analysis, it has been proved that the α-Al13(Fe, V)3Si phase existing in as-cast Al–Fe–V–Si alloy is wholly or partly inhibited for Al93.3-xFe4.3V0.7Si1.7Mmx (x=0.5, 1.0, 3.0) crystalline alloys. In addition, a new phenomenon has been reported that the lattice parameter of as-quenched Al–Fe–V–Si–Mm alloys decrease with increasing Mm content; the "cell lessening effect". This effect is presumably due to the results of composite interactions between rare-earth elements and alloy elements.

The dynamics of the generation of the various spike trains in neural pacemakers is of fundamental importance to the understanding of neural coding. Recent studies have demonstrated, theoretically and experimentally, that neural pacemakers produce chaotic oscillations. Deeper analyses in several neuronal models have revealed many nonlinear phenomena including period-adding bifurcations whose existence has not been experimentally confirmed. In this letter, we reported that the period-adding bifurcation with chaos was observed in the interspike interval (ISI) series generated by an experimental neural pacemaker when the extracellular calcium concentration was changed or a potassium channel blocker was administered at the site of the pacemaker. We also simulated our experimental discoveries by computing a generalized model of excitable cells. The chaotic phenomenon in the experiment and that in the model were demonstrated and compared using the nonlinear forecasting and surrogate data methods.

We report fabrication of silicon nanohole radial p-n junction solar cells (SCs) using thermal annealing of silver films with metal-catalyzed electroless etching (MCEE). A balanced approach between the cost and controllability of the nanostructure fabrication is used to manufacture the silicon SCs. Based on our experimental results, the size and distribution of the nanoholes can be controlled by varying the thickness of the Ag films and the temperature for thermal annealing. In this work, we performed investigations on the dependencies of the device properties on the nanohole size. Detailed structural information for the silicon nanohole SCs was provided by TEM measurement. Our experimental results indicate substantial improvements in the cell efficiency for our devices compared to reported values for random nanostructure SCs.

We report fabrication of random nanometer-scale radial p-n junction solar cells (SCs). Nanoholes were fabricated on the Si wafer by combining silver film annealing and metal catalyzed electrochemical etching (MECC) of the material. The dimension of the holes can be adjusted by varying the annealing conditions and the thickness of the Ag film. Systematic investigations on the effects of the nanohole size and the doping conditions on the cell efficiency were performed.

The geogrid’s horizontal deformation of geogrid reinforced earth retaining wall was observed installing the gentle displacement gauge on the geogrids. And the strain rule which increase along with the tensile speed and the strength increasing were concluded from geogrid indoor test at the same time. The geogrid’s horizontal deformation rule of geogrid reinforced earth retaining wall was concluded by observing and analyzing the indoor and spot test result and the master of horizontal deformation controlling was confirmed.

The field test of moulding concrete rigid panel faced geogrids reinforced soil retaining wall is done in the Gan (Zhou)-Long (Yan) railway main line of China. The basement vertical pressure of reinforced soil retaining wall is non-linear along the reinforcement length, and the maximum value is at the middle of the reinforcement length, moreover the value reduce gradually at former and bottom. The testing lateral pressure of the reinforced soil wall is non-linear along the height and the value is less than the active lateral earth pressure. The distribution of tensile strain along reinforcement at the upper wall is single peak value, but the distribution of tensile strain along reinforcement at the lower wall is twin peak value. The potential fracture plane at upper wall is similar to “0.3H method”, but the potential fracture plane at lower wall is near to the active Rankine earth pressure theory. The position of the maxmium lateral displacement of the wall face during construction at lower wall, moreover the position of the maxmium lateral displacement of the wall face after construction at top of the wall.

The effect of adrenomedullin (AM) on blood pressure and tension of aortic rings were studied in normal and in either spontaneous or renal hypertensive rats (SHR/RHR). The distribution characteristics of AM in viscera was also investigated. It was found that the hypotensive action of AM was far more prominent in hypertensive than in normotensive rats. The tension lowering action on the aortic rings is dose dependent and requires the presence of endothelium. Immunohistochemistry reactivity of AM of different degrees were also found in lung, kidney and myocardium, in addition to cells of pheochromocytoma and adrenomedulla. It was suggested that AM may play an important role in the regulation of blood pressure and visceral blood circulation.

Six different glycosyltransferases that are active with glycosphingolipid substrates have been purified from Golgi-membranes after solubilization with detergents. It appears that GalT-4(UDP-Gal:GlcNAc-R1 beta 1-4GalT), GalNAcT-2(UDP-Gal:Gal alpha-R2 beta 1-3GalNAcT) and FucT-2(GDP-Fuc:Gal beta GlcNAc-R3 alpha 1-2FucT) are specific for oligosaccharides bound to ceramide or to a protein moiety. These are called CARS (carbohydrate recognition sites) glycosyltransferases (GLTs). On the other hand, GalT-3(UDP-Gal:GM2 beta 1-3GalT), GalNAcT-1(UDP-GalNAc:GM3 beta 1-4GalNAcT) and FucT-3 (GDP-Fuc:LM1 alpha 1-3FucT) recognize both hydrophobic moieties (fatty acid of ceramide) as well as the oligosaccharide chains of the substrates. These GLTs are called HY-CARS (hydrophobic and carbohydrate recognition sites). D-Erythro-sphingosine (100-500 microM) modulates the in vitro activities of these GLTs. Modulation depends on the binding of D-sphingosine to a protein backbone, perhaps on more than one site and beyond transmembrane hydrophobic domains. Control of GLTs by free D-sphingosine was suggested with the concomitant discovery of ceramide glycanase in rabbit mammary tissues. The role of free sphingosine as an in vivo homotropic modulator of glycosyltransferases is becoming apparent.

High level of phosphoenolpyruvate carboxylase (PEPC) gene was stably inherited and transferred from the male parent, PEPC transgenic rice, into a female parent, japonica rice cv. 9516. Relative to the female parent, the produced JAAS45 pollen lines exhibited high PEPC activity (17-fold increase) and also higher photosynthetic rates (about 36 %-fold increase). The JAAS45 pollen lines were more tolerant to photoinhibition and to photo-oxidative stress. Furthermore, JAAS45 pollen lines, as well as their male parent, were tested to exhibit a limiting C4 cycle by feeding with exogenous C4 primary products such as oxaloacetate (OAA). Thus the PEPC gene and photosynthetic characteristics of PEPC transgenic rice could be stably transferred to the hybrid progenies, which might open a new breeding approach to the integration of conventional hybridization and biological technology.

15090 Background: Although results of clinical studies have demonstrated FDG PET/CT improved target volume delineation in various tumors, only few studies compared delineation based on PET/CT with pathologic examination. Aim of our study was to compare anatomic imaging modalities including computed tomography (CT), esophagram, endoscopy with FDG PET/CT for delineation of gross tumor volume (GTV) in esophageal carcinoma and to validate the results with the pathologic examination. Methods: Thirty patients with stages II-III squamous cell carcinoma underwent transthoracic esophagectomy were enrolled. PET/CT, esophagram and endoscopy were performed with patients before operations. The length of the lesion on the PET/CT scan and on the CT portion of the PET/CT and the PET scan alone was determined independently by 3 separate investigative groups. PET/CT scan was evaluated by visual inspection for abnormality. A standard uptake value (SUV) of 2.5 was used in the PET scan to delineate the tumor extent. The lengths of GTVs determined with the five modalities (PET/CT, PET, CT, esophagram and endoscopy) were compared quantitatively and validated with the pathologic specimen. The sizes of the tumors were measured by pathologic examination which was considered as the gold standard. Results: Of the 30 patients, 9 had T2 tumors, 20 had T3 tumors and 1 had T4 tumor with an involvement of pleura. Three tumors were located at the upper esophagus, 14 at the middle esophagus, 13 at the lower esophagus. The mean length of the carcinoma was 5.85cm(SD 2.50cm) measured by pathologic examination, 5.79cm (SD 2.04cm) as determined by PET scan, 5.14cm (SD 1.65cm) by PET/CT scan, 5.42 cm(SD 2.42cm)by CT scan, 5.50cm(SD 2.79cm) by endoscopy, and 6.07cm(SD 2.75cm) by esophagram respectively. Although the lengths of the tumors as measured by the five imaging modalities were no significant difference, the result of PET was the most accurate. Conclusions: Compared with tumor lengths measured by pathologic examination, PET with a SUV 2.5 was found to be the most accurate modality and can help the radiation oncologist delineate the GTV of esophageal carcinoma precisely. No significant financial relationships to disclose.