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Objective: This study aimed to examine the role of long non-coding RNA PCED1B antisense RNA 1 (PCED1B-AS1) in the development of hepatocellular carcinoma (HCC). Methods: A total of 62 pairs of HCC tissues and adjacent non-tumor tissues were obtained from 62 HCC patients. The interactions of PCED1B-AS1 and microRNA-34a (miR-34a) were detected by dual luciferase activity assay and RNA pull-down assay. The RNA expression levels of PCED1B-AS1, miR-34a and CD44 were detected by RT-qPCR, and the protein expression level of CD44 was determined by Western blotting. The cell proliferation was detected by cell proliferation assay, and the cell invasion and migration by transwell invasion assay. The HCC tumor growth after PCED1B-AS1 was downregulated was determined by in vivoanimal study. Results: PCED1B-AS1 was highly expressed in HCC tissues, which was associated with poor survival of HCC patients. Furthermore, PCED1B-AS1 interacted with miR-34a in HCC cells, but they did not regulate the expression of each other. Additionally, PCED1B-AS1 increased the expression level of CD44, which was targeted by miR-34a. The cell proliferation and invasion assay revealed that miR-34a inhibited the proliferation and invasion of HCC in vitro, while CD44 exhibited the opposite effects. Furthermore, PCED1B-AS1 suppressed the role of miR-34a. Moreover, the knockdown of PCED1B-AS1 repressed the HCC tumor growth in nude mice in vivo. Conclusion: PCED1B-AS1 may play an oncogenic role by regulating the miR-34a/CD44 axis in HCC.

Meniscus is a wedge-shaped fibrocartilaginous tissue, playing important roles in maintaining joint stability and function. Meniscus injuries are difficult to heal and frequently progress into structural breakdown, which then leads to osteoarthritis. Regeneration of heterogeneous tissue engineering meniscus (TEM) continues to be a scientific and translational challenge. The morphology, tissue architecture, mechanical strength, and functional applications of the cultivated TEMs have not been able to meet clinical needs, which may due to the negligent attention on the importance of microenvironment in vitroand in vivo. Herein, we combined the 3D (three-dimensional)-printed gradient porous scaffolds, spatiotemporal partition release of growth factors, and anti-inflammatory and anti-oxidant microenvironment regulation of Ac2-26 peptide to prepare a versatile meniscus composite scaffold with heterogeneous bionic structures, excellent biomechanical properties and anti-inflammatory and anti-oxidant effects. By observing the results of cell activity and differentiation, and biomechanics under anti-inflammatory and anti-oxidant microenvironments in vitro, we explored the effects of anti-inflammatory and anti-oxidant microenvironments on construction of regional and functional heterogeneous TEM via the growth process regulation, with a view to cultivating a high-quality of TEM from bench to bedside.

AbstractBackground:The safe closure of atrial septal defect with deficient posterior-inferior or inferior vena cava rim is a controversial issue. Few studies have been conducted on the closure of atrial septal defect with deficient posterior-inferior or inferior vena cava rim without fluoroscopy. This study evaluated the feasibility and safety of echocardiography-guided transcatheter closure of atrial septal defect with deficient posterior-inferior or inferior vena cava rim.Methods:The data of 136 patients who underwent transcatheter atrial septal defect closure without fluoroscopy from March 2017 to March 2020 were retrospectively analysed. The patients were classified into the deficient (n = 45) and sufficient (n = 91) posterior-inferior or inferior vena cava rim groups. Procedure and the follow-up results were compared between the two groups.Results:Atrial septal defect indexed diameter and the device indexed diameter in the deficient rim group were both larger than that in the sufficient rim group (22.12 versus 17.38 mm/m2, p < 0.001; 24.77 versus 21.21 mm/m2, p = 0.003, respectively). There was no significant difference in the success rate of occlusion between two groups (97.78% in the deficient rim group versus 98.90% in the sufficient rim group, p = 1.000). During follow-up, the incidence of severe adverse cardiac events was not statistically significant (p = 0.551).Conclusions:Atrial septal defect with deficient posterior-inferior or inferior vena cava rim can safely undergo transcatheter closure under echocardiography alone if precisely evaluated with transesophageal or transthoracic echocardiography and the size of the occluder is appropriate. The mid-term results after closure are similar to that for an atrial septal defect with sufficient rim.

Superhard material BC2N compound has attracted much attention because of its high hardness and stability. Here, we take Pmm2-BC2N as an example; the phonon dispersion, electronic structure, and mechanical properties of Pmm2-BC2N crystal structure are studied theoretically by using first-principles calculation method. The results show that it is dynamically and mechanically stable. The reason of forming strong covalent bonds between B, C, and N atomic orbitals is analyzed by means of state density. The shear modulus, bulk modulus, Young’s modulus, and Poisson’s ratio are calculated. The results show that the shear modulus is larger than that of the bulk modulus, and it is a brittle material. In addition, we calculated the Vickers hardness of Pmm2-BC2N is 74.9GPa.

In order to discover novel anti-inflammatory agents for treatment of arthritis and based on preliminary structure–activity relationships, four series (A–D) of total 90 new pyrazolo[4,3-d]pyrimidine compounds were designed and synthesized. All the compounds have been tested for their anti-inflammatory activities by inhibiting of LPS-induced NO production. A clear structure–activity relationship has been concluded step by step, and finally 3,4,5-trimethoxystyryl-1H-pyrazolo[4,3-d]pyrimidine was found to be the most active scaffold. Among them, compound D27was discovered as the most potent anti-inflammatory agent (IC50= 3.17 μM) with low toxicity and strong inhibitory of NO release (IR = 90.4% at 10 μM). This compound also showed potent inhibition of iNOS with IC50value of 1.12 μM. Preliminary mechanism studies indicated that it could interfere with the stability and formation of active dimeric iNOS. The anti-inflammatory effect of this compound was determined by adjuvant-induced arthritis in rat model. We believe these findings would further support the study of rational design of more efficient iNOS inhibitors in the future.

The IL-33/ST2 axis is involved in the pathogenesis of many diseases such as autoimmune diseases, cancer, and heart failure. However, studies of the IL-33/ST2 pathway in HBV-related acute-on-chronic liver failure (HBV-ACLF) are lacking. The present study aimed to determine the prognostic role of serum IL-33/soluble ST2 (sST2) in HBV-ACLF.

The basilar artery has the most perioperative complications in stenting compared to the other intracranial arteries. We aim to study whether the procedural safety in stenting for basilar stenosis has improved. This study was a single-arm, non-randomized trial that included historically controlled patients for comparison. Between January 2012 and March 2019, 147 consecutive patients with symptomatic basilar stenoses receiving elective stenting treatment were included in current basilar artery stenting (BAS) group. The prospectively collected and registered 120 patients by the same interventional team from September 2001 to November 2011 were set as historical BAS group for control. A total of 267 individuals were included in this study, with a mean age of 59.5 ± 8.1 years. The proportion of patients with lesion length >15 mm was 26.5% (39/147) in the current BAS group versus 4.2% (5/120) in the historical BAS group. We found significant differences between these 2 groups in Mori A (17.7% vs 42.5%) and Mori C patients (42.9% vs 13.3%). The proportion of patients receiving preoperative high-resolution magnetic resonance (HRMRI) evaluation was 83.0% (122/147) in the current BAS group versus 20.8% (25/120) in the historical group (P < .05). Balloon-expendable stent (BES) (n = 1), Wingspan (n = 34), and Enterprise (n = 112) stents were placed in the current BAS group. In contrast, only balloon-expendable stent (BES) (n = 48) and Wingspan (n = 72) were deployed in the historical BAS group. The incidence of the safety endpoint (SE) was 4.1% (involving 6 patients) in the current BAS group versus 11.7% (involving 14 patients) in the historical BAS group (P < .05). In multivariate analysis, no risk factor was associated with the occurrence of the safety endpoint (SE). When BAS cases operated by the surgical team accumulated to 120 to 150, the incidence of complications decreased significantly. This is the largest sample size study to discuss the safety of BAS. The significantly decreased incidence of complications indicates that the improving technical measures and the accumulation of operation experience are necessary.

Three-dimensional (3D) elastic-plastic finite element model (FEM) is adopted to research the effect of side groove on the crack-front J-integral for different size of Compact Tension (CT) specimens. Although the side-grooved CT specimen is widely used in the existing test method, such as ASTM E1820-13, the test data of fracture toughness is varying with the various geometric parameters. Before FE calculation, the material properties of Q345 steel were obtained by uniaxial tensile test, especially for the true stress-strain relationship. In this paper, it focuses on the numerical study of geometric parameter effects on the fracture toughness. Toward this end, the commercial FE software of ABAQUS is adopted to calculate the J-integral. Since the side groove of CT specimen is so important to make the fracture test success, the various parameters of side groove is intensively analyzed for obtaining the accurate J-integral along the crack front, including the effects of the angle, depth and root radius. In fact, the side groove effect is so significant around the crack front that cannot be ignored in the J-integral calculation. Through rigorous FE investigation, the influence of the side groove on the fracture toughness testing is fully disclosed, and the appropriate side groove configuration is recommended accordingly.

Modern timber buildings are more and more popular with their characteristics of green, environmental protection, low carbon. According to their structure, they are divided into light wood frame construction, sawn and log timber structures, glued laminated timber structures, log cabins. This paper analyzes the structure supporting structural system of log cabins, from material requirements, structural design to production process, supplemented by practical case to demonstration, to explore the design method of log cabin’s structure supporting system.

Construction of a project at a proposed site requires understanding of the geological and hydrogeological conditions for the purpose of engineering design and environmental impact assessment. However, investigation and assessment of the site conditions may be challenging for limestone areas due to the irregular occurrence and development of karst. This paper presents a demonstration of the site investigation and assessment for the karst hydrogeological conditions through a case study of a site with complex lithology. A joint on-site surveying and mapping, drilling, geophysical exploration, supplemented by in-situ and laboratory tests, was implemented in the assessment. Results indicate the site area presents a multiplicity in lithology with steep attitude stratum. Northern part of the site distributed shales suffering different degree of weathering, while the rest areas were developed with carbonate rocks. Fracture zones with north-west and north-east trend were developed at the site, which are prone to form strong runoff zone of the groundwater. No shallow buried river, hall-or corridor-type karst caves were detected at the site, neither of large-scale well-connectivity karst channels. However, many small karst and soil caves were developed at the site, which suggest a post treatment of engineering measures for the purpose of engineering and environmental safety. Based on the distribution of karst ratio calculated from boreholes, the proposed site area can be divided into 3 zones of very-strongly developed zone with a karst ratio around 71.2%, strongly developed zone with a ratio around 26.3% and intermediate-slightly developed zone with a ratio of 15.0%. Characteristics of each sub-zones are analyzed regarding to the general layout and later engineering design of the power plant project. This study provides an example of a joint study for site condition assessment at karst areas with complex lithology. Such an assessment is crucial to the site selection, project layout, engineering design and to later environmental impact assessment.

In many species, nestling demands vary continuously during early development and both parents have different parental care strategies at each nestling age. Sexual conflict arises when each parent expects its partner investing more in parental care. It is largely unknown how the two parents respond to the dynamics of nestling demands and resolve the sexual conflict during nestling period, especially on Qinghai-Tibetan Plateau. To address this question, we monitored parental care behaviors of horned larks ( Eremophila alpestris) using video-recording systems. We found that male horned larks invested less in parental care, but had a larger body size than females, which is consistent with the parental investment hypothesis. Only the female brooded nestlings, but both parents contributed to feeding efforts. Feeding rates of males and females were negatively correlated, indicating that they used evolutionarily stable strategies. Strategies of parental care via nestling age were sex-specific. Females continuously adjusted care behaviors to follow the dynamics of nestling demands as nestling age increased, such as decreasing brood attentiveness and increasing feeding rate. By contrast, male feeding rate showed no significant correlation with nestling age, but increased with the synchrony feeding rate. We suggest the synchrony feeding behavior may act as a control measure for females to promote and assess the males' contribution. We consider low mating opportunities drive males to act as assistants for females, and correspondingly cause males to pay less attention to nestling demands than females. [ABSTRACT FROM AUTHOR]

This paper presents a node shift method to find the optimal distribution of nodes in single-layer reticulated shells. The optimization process searches for the minimum strain energy configuration and this leads to reduced sensitivity in initial imperfections. Strain energy sensitivity numbers are derived for free shift and restricted shift where nodes can move freely in the 3D space or have to move within a predefined surface respectively. Numerical examples demonstrate the efficiency of the proposed approach. It was found that optimized structures achieve higher ultimate load and are less sensitive to imperfections than the initial structure. The configuration of the final structure is closely related to factors like the initial structural configuration, spatial conditions, etc. Based on different initial conditions, architects can be provided with diverse reasonable structures. Furthermore, by amending the defined shapes and nodal distributions, it is possible to improve the mechanical behavior of the structures.

This study was conducted to investigate the effects of magnesium (Mg) supplementation on the growth performance, muscle fiber development and flesh quality of Megalobrama amblycephalafed a high-carbohydrate (CHO) diet. In vivo, six experimental diets, a control diet (30% CHO, C), and five Mg supplementation levels (0 (HC1), 200 (HC2), 400 (HC3), 800 (HC4) and 1200 (HC5) mg kg−1, respectively) of high-CHO diet (45% CHO), were formulated and then fed to M. amblycephala(initial weight 43.15 ± 0.43 g) for 13 weeks. Results showed that the HC1 diets remarkably decreased weight gain rate (WGR), specific growth rate (SGR), water holding capacity (WHC), pH 24 h postmortem, collagen content, textural properties (hardness, tenderness, chewiness and resilience), muscle fiber density, succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) activities, as well as transcriptions of ampkα2, pgc-1α, mrf-4, myf-5and myf-6compared with the C group, but muscle AMP/ATP ratio, ATPase activities and mstnaand mstnbtranscription showed an opposite trend. The HC3 group of fish obtained relatively high values of WGR, SGR, muscle lipid and protein content, collagen content, textural properties (hardness, tenderness, chewiness and resilience), fiber density, SDH and MDH activities, AMP/ATP ratio as well as transcriptions of ampkα1, pgc-1α, myod, myogand myf-5compared with other HC groups. In vitro, the isolated primary hepatocytes from M. amblycephalawere assigned into four experimental groups: a control group (5.5 mM glucose, Control), a high glucose group (30 mM glucose, HG), an AICAR group (30 mM glucose + 250 μM AICAR, HGA) and an MgSO4group (30 mM glucose + 2 mM MgSO4, HGM). Results showed that MgSO4treatment remarkably increased p-Ampk/t-Ampk ratio, Pgc-1α protein content and transcriptions of ampkα1, ampkα2and pgc-1αcompared with the HG group. Overall, based on regression analysis for SGR, the optimal Mg level of M. amblycephalafed high-CHO diets was 366.67 mg kg-1, which was consistent with the above results that fish fed HC3 diets displayed higher the growth performance, muscle fiber density and flesh quality of M. amblycephala.

This paper analyzes the synthesis of vinyl acetate production process and technology, and applied the artificial neural network modeling approach, by using the adaptive learning rate BP learning algorithm, then established the medium temperature control of BP neural network in the structure model of the VAc synthesis process of flurried bed synthesis reactor, by controlling medium temperature of the synthesis reactor, the results show that: Be able to effectively will in reactor temperature control in good accuracy.

In recent years, the phenomenon of vehicle overload in highway transportation is more and more serious. The three-dimensional dynamic FEM was adopted and a three-dimensional simulative model for asphalt pavement with subgrade based on cross-anisotropy under moving load was established by the large-scale finite element analysis software ABAQUS. The response of the stress in the pavement structure was got by using ABAQUS/Standard code. During deceleration, The simulation analysis results under the rated load were compared with those under the different overload ratio. The results show that, under moving load, the surface course of pavement is mainly in three dimension compressive stress state. The horizontal load caused by deceleration has a remarkable effect on the longitudinal stress and the horizontal shearing stress. The stress of the pavement structure under overload is much greater than that caused by the rated load. And the greater the overload ratio, the greater the deviation between them.

Punch forming is widely used in many fields such as car industry, aviation, and mechanical industry. Along with the new requirement such as velocity, efficiency, costing of punch forming, there is more and more failure appearance. For example, fracture, fold and spring back. In this paper, a detailed analysis of punch forming is done by FEM(finite element method), and the stresses of punch forming are obtained at every phase of punch. This work is very useful for mold design, punch forming parameters set and material properties test.

Aiming at the disadvantages of large computing, slow convergence and easily trapping into local minima of traditional BP network, a new method named batch momentum learning algorithm which combining the momentum with batch gradient descent algorithm has been used to be as the learning algorithm of connection weights and threshold of BP neural network, through using this method to forecast the prevalence of plant disease, the convergence speed of BP neural network has been enhanced.

Effect of cationic polymer on granulation and COD removal efficiency in lab scale UASB reactors was examined, treating low-strength wastewater (COD 300-500mg l-1) at room temperature. It was shown that cationic polymer was more effective for enhancing sludge granulation and COD removal efficiency as compared to the control experiment (without additives). After day 166 of operation, the amount of granules size above 0.5mm accounted for 32.1% of total sludge, higher than that of control experiment (19.3%). At 1.03 kg COD m-3 d-1 of OLR and 9.8 h of HRT, the effluent VFA had a maximum value of 168mg l-1 and 240mg l-1 in Reactor A and B respectively. The polymer-amended reactor took 36days to receive 1.44 kg COD m-3 d-1 of OLR at the 7.8 h of HRT, shorter than the control reactor (54days). The two reactors obtained above 80% in COD removal efficiency. It is shown that UASB reactor can also achieve higher COD removal treating low strength wastewater at room temperature.

The structural morphogenesis methods are numerical methods for seeking various‘good structure shape’ based on mathematical and mechanical principles. The methods are to realize the coordination between structural shape and mechanical properties. In this paper, the height adjusting method and Extended-ESO (extended evolutionary structural optimism) method are successfully applied in practical engineering design schemes, which could be a meaningful reference and a powerful tool to the present design in structural shape and mechanical performance.

In this article, flow and dispersion of pollution in hilly terrain was investigated experimentally in the wind tunnel. A turbulent boundary layer flow was simulated as the approaching flow which passed over the hilly model. Tufts visualization was employed to obtain the wind field of mean flow direction. Methane mixed with pure air was chosen as the tracer for studying stack plume dispersion. Tufts visualization results showed the wind field of mean flow direction which revealed how the winds were flowing over the hilly terrain model for various wind directions. Reversed flows were observed at the region of leeside of main hills or mountains of the terrain model. The plume average height increased with increase in the topography change parameter of the hilly terrain. When varying the topography change parameter of flat terrain into hilly terrain, the plume vertical dispersion parameter increased, accordingly.

This paper proposes a new reliability modeling and analysis approach based on Stochastic Petri Nets by employing the logical relations in the RBD to cope with the inadequacy in various quantitative reliability analysis techniques, such as Reliability Block Diagram (RBD) and Markov analysis of control system in process industry. In this paper, the proposed new approach is elaborated and its feasibility and effectiveness is illustrated in a study case. As the results show, the proposed approach is demonstrated more straightforward and visual than Markov method. This research also bears significance in its application in the reliability analysis of general system in process industry.

An innovative nuisance trip calculation method based on Markov model was proposed in this paper which was used to evaluate the effect of repairment on system reliability. By analysis of the availabilities of classic 1 out of 2 (1oo2) repairable system, a new definition of spurious trip was put forwarded where online repair was considered. Compared with the benefits obtained by online repairment, the repair-caused-nuisance-trip was analyzed in this paper. Numerical calculation revealed that the online repair is helpful for anti-spurious trip in 1oo2 redundant system. Dangerous failures, if not repaired or cannot be online fixed, have complex influence on system reliability. The dangerous failure is sometimes benefit for anti-spurious performance if it is not repaired. But Mean Time To Failure Spurious (MTTFs) reduces with the increase of dangerous failure provided that dangerous failure rate is bigger than safe failure rate. Meanwhile, the finding that common cause can reduce the chance of nuisance trip was also proposed in this paper, though the influence is too small to be neglected.

Given the existing difficulties in conventional reliability models and the limitations of the current SPN software tools in terms of modeling system reliability, a software tool for modeling system reliability based on SPN named RelSPN@zer is developed, describing both the general structure and the underlying numerical methods of the tool. RelSPN@zer provides a unified framework for the modeling and evaluation of SPN running under MATLAB environment and is especially tailed to the system reliability analysis. Many metrics of system reliability can be obtained both under stationary and transient state. An example is given to illustrate the use of this package.

The ability of executing assigned function of repairable system under certain condition is quite different from that of single unit due to redundant configuration. It is well understood that proper management strategy can greatly prolong the mean time to failure (MTTF) of repairable system. By introducing operating cycle or partial test interval, repair time and maintenance efficiency, the MTTF of classic 1oo1, 1oo2 and 2oo3 redundant systems is studied in this paper. It is found that periodical maintenance can dramatically improve the availability of repairable system, while the efficiency of maintenance has great influence on the MTTF of repairable system.

The quantitative analysis of “domino” effects is one of the main aspects of hazard assessment in chemical industrial park. This paper demonstrates the application of heterogeneous stochastic Petri net modeling techniques to the quantitative assessment of the probabilities of domino effects of major accidents in chemical industrial park. First, five events are included in the domino effect models of major accidents: pool fire, explosion, boiling liquid expanding vapour explosion (BLEVE) giving rise to a fragment, jet fire and delayed explosion of a vapour cloud. Then, the domino effect models are converted into Generalized Stochastic Petri net (GSPN) in which the probability of the domino effect is calculated automatically. The Stochastic Petri nets’ models, which are state-space based ones, increase the modeling flexibility but create the state-space explosion problems. Finally, in order to alleviate the state-space explosion problems of GSPN models, this paper employs Stochastic Wellformed Net (SWN), a particular class of High-Level (colored) SPN. To conduct a case study on a chemical industrial park, the probability of domino effects of major accidents is calculated by using the GSPN model and SWN model in this paper.

A new lattice Bhatnagar–Gross–Krook (LBGK) model for a class of the generalized Burgers equations is proposed. It is a general LBGK model for nonlinear Burgers equations with source term in arbitrary dimensional space. The linear stability of the model is also studied. The model is numerically tested for three problems in different dimensional space, and the numerical results are compared with either analytic solutions or numerical results obtained by other methods. Satisfactory results are obtained by the numerical simulations.

ABSTRACTAs a part of a basic research project on Xeno-transplantion, we have been engaged in the derivation of embryonic stem cell lines from Chinese mini swine. Here, we reported for the first time the establishment of two porcine EG cell lines (BPEG1 and BPEG2) from primordial germ cells of genital ridges of a 28 and a 27 d embryos respectively. Their pluripotent nature has been identified by colony morphology, marker characterization as well as by in vitro and in vivo differentiation. These porcine EG cells are potentially useful for further basic studies.

ABSTRACTAs a part of a basic research project on Xeno-transplantion, we have been engaged in the derivation of embryonic stem cell lines from Chinese mini swine. Here, we reported for the first time the establishment of two porcine EG cell lines (BPEG1 and BPEG2) from primordial germ cells of genital ridges of a 28 and a 27 d embryos respectively. Their pluripotent nature has been identified by colony morphology, marker characterization as well as by in vitro and in vivo differentiation. These porcine EG cells are potentially useful for further basic studies.Cell Research (2003) 13, 195–202. doi:10.1038/sj.cr.7290164

The authors wanted to evaluate the usefulness of 99TmTRODAT‐ 1 as an imaging agent for measuring changes in dopamine transporter concentrations in Parkinson disease (PD) and correlate the findings to the severity of the disease as measured by the Hoehn and Yahr scale (HIY). Twenty‐two healthy volunteers and 27 patients with PD of H/Y stage I‐IV were evaluated. Acquisitions were performed 2 hours after injection of 99TmTRODAT‐ 1. Regions of interest were drawn over the striatum and the cerebellum, and the ratios of striatum‐to‐cerebellum (ST/CB) were calculated. Patients with PD showed a significant decrease in the striatal uptake of 99Tm‐TRODAT‐1 compared to healthy volunteers, and the ST/CB ratios were closely related to the stage of PD. The present study demonstrates that it is possible to visualize and quantify changes in dopamine transporter in the striatum of patients with PD using 99Tm‐TRODAT‐1 and SPECT with good correlation to H/Y stage and unified Parkinson's disease rating scale (UPDRS) scale.

CHO cells were pulse-labeled with 125I-iododeoxyuridine, harvested 30 min or 5 h after labeling, and stored at-196oC for accumulation of 125I decays. The 30- min groups yielded low-LET survival curves (large shoulder, D0136 decays/cell); 5-h groups showed a high-LET pattern of cell killing (no shoulder, D045 decay/cell). Surprisingly, the shift in 125I action was abolished in cells exposed to HAT medium; both 30-min and 5-h cell groups exhibited high-LET-type killing (no shoulder, D052 decays/cell). The striking difference in cell death was not accompanied by any change in induction or repair of DNA DSBs, but the pattern of micronucleus formation (and by implication chromosome damage) did parallel 125I-induced cell death. These findings suggest that cell killing may not be directly linked to the absolute number of DNA DSBs and that damage to higher-order genome structures may be an important factor in radiation-induced cell death.

The present study utilized the Lagrangian discrete parcel method to simulate the spreading of an oil spill on the coastal waters. The physical transport processes which include oil slick mechanical spreading, current advection, turbulent diffusion, evaporation, dissolution, and shoreline conditions are considered. Oil slick spreading area as a function of time for different conditions was also investigated. The simulation results are good in comparison with the field observation data. Numerical calculation results show that the whole oil slick splits into small slicks easier for a continuous spill than for an instantaneous spill. With a higher drift velocity, the whole oil slick splits into small slicks more easily.

The structure of the Reynolds stress in a turbulent flow over the multiple windbreaks of half-circular sections across-wind was investigated experimentally in the boundary layer wind tunnel. The quadrant analysis theory was applied to analyze the turbulent stress signals by partitioning the Reynolds stress into inward interaction, ejection, outward interaction, and sweep events in accordance with whichever quadrant the (u', w')belongs to. u' and w' are the stream wise and transversewise velocity fluctuations, respectively The results show that when Z/H < 1, X/H < 20, the sweep events are the largest contributors to the Reynolds stress followed by the ejection events while the inward and outward interactions are negative contributors. Z is the distance from the wall, X is the downstream distance, and H is the height of windbreak. The stress contributions by sweeps and ejections are almost the same when Z/H < 1, X/H > 30.

The effects of iron deficiency on the cochlea were studied in growing rats fed with a basic iron-deficient diet for 80 days. The electrophysiological changes (auditory thresholds raised more than 15 dB) were observed in 47% of the cochleas of iron-deficient rats. When these organs of Corti were examined by scanning electron microscopy, abnormalities of outer or inner hair cells were found, as follows: (1) fusion and torsion of the stereocilia, (2) coalescence of adjacent stereocilia in the same row, (3) loss of sensory hair stiffness, and (4) loss of stereocilia. Within each lesion, the neighbouring supporting cells and their microvilli showed no damage. The findings indicate that cochlear impairment can be induced by iron deficiency. The peroxidative mechanisms responsible for the lesions of stereocilia in iron deficiency are discussed.

Mössbauer effect spectroscopy (MES) studies of cobalt-containing fused iron catalysts show that different cobalt distributions occur in irregularly shaped catalysts (formed by natural cooling of the fused mass in air) and in ball-shape catalysts (formed in water by sudden cooling). The Co2+ ions replace Fe2+ ions in the B sites of the inverse spinel structure of Fe2O4 for the former catalyst, while a relatively even distribution over A and B sites occurs for the latter. The above results are supported by X-ray diffraction (XRD). For the irregular catalysts, the activity and specific surface area increase to some extent with increasing cobalt content and decreasing atomic iron ratios (i.e.Fe2+/Fe3+). For the ball-shape catalyst, in spite of the somewhat smaller specific surface area, a higher specific activity results in an overall activity that is incomparable to that of the irregular catalyst; the pore surface distribution is shifted to larger pores. The reaction rate constant decreases with increasing total pressure. The ball-shaped catalyst follows the relationkT.P∼exp(jp), while the irregular catalyst is fits the Nielsen equation,kT.P∼pi, wherei andj are small negative numbers. The intrinsic reduction kinetics of the ball-shape catalyst are best in line with thecontracting sphere model, and reduction of industrial size catalysts also shows that cobalt promotes the reduction of the catalyst. On the other hand, the uneven distribution of Co2+ ions in the irregular catalyst causes its intrinsic reduction kinetics to deviate from the contracting sphere model. We consider that the easier reduction of the cobalt containing catalyst may be caused by the much easier reduction of the CoFe2O4 present.

ABSTRACTIn this study, an integral bubble plume model is applied to simulate the behaviors of offshore gas well blowout under seawater. The numerical model simulation results are good in comparison with the field data. The bubble plume radius, upward velocity and buoyancy for different ambient fluid stratification and gas flow rate cases are calculated and investigated. Analysis of the calculated results reveal that: (1) The bubble plume radius increases but terminal rise height decreases when the gas flow rate decreases. (2) Ambient sea water with strong density stratification will inhibit the bubble plume rise and reduce its terminal rise height. (3) Sea water stratification effect on the bubble plume terminal rise height is more significant than that of gas flow rate in several orders of magnitude.