Toxicogenomic analysis of susceptibility to inhaled urban particulate matter in mice with chronic lung inflammation

Background  

Individuals with chronic lung disease are at increased risk of adverse health effects from airborne particulate matter. Characterization of underlying pollutant-phenotype interactions may require comprehensive strategies. Here, a toxicogenomic approach was used to investigate how inflammation modifies the pulmonary response to urban particulate matter.     

The effect of lithium oxide on the threshold field of ZnO varistors

Lithium oxide in form of Li₂CO₃ solution is added with contents of 0–200 ppm to two ZnO-based varistors standard formulations, once with Sb₂O₃ and the other without. According to Li₂CO₃ concentration, both threshold field and energy absorption capability evolution are studied. It is found that with the benefit of antimony, the lithium allows reaching high threshold field but concomitantly, low energy absorption capability. Without antimony, threshold fields up to 300 V/mm are attained, associated with a fair energy absorption capability. With 100 ppm of Li₂CO₃, optimum couple of values (315 V/mm; 115 J/cm³) is achieved. With 200 ppm of Li₂CO₃, threshold field exceeds 500 V/mm but energy absorption capability falls below 50 J/cm³. Correlations with SEM microstructures observations suggest that lithium increases voltage barrier height by decreasing donor density and that spinel phases (Zn₇Sb₂O₁₂) have detrimental effects on the electrical absorption capability by limiting the density of current, reducing the effective current path from one ZnO grain to another.     

A Combined Multi-Technique In Situ Approach Used to Probe the Stability of Iron Molybdate Catalysts During Redox Cycling

A setup combining a number of techniques (WAXS, XANES and UV–Vis) has been used to probe the stability of an iron molybdate catalyst during redox cycling. The catalyst was first reduced under anaerobic methanol/helium conditions, producing formaldehyde and then regenerated using air. Although in this test-case the catalyst and conditions differ from that of a commercial catalyst bed we demonstrate how such a setup can reveal new information on catalyst materials. In particular we observe the formation of two phases during reduction; one which we propose to be an oxygen deficient ‘pseudo-molybdate phase’, the other a molybdenum carbide-like phase, both produced as oxygen is removed from the catalyst. Standard in situ techniques could detect such transient phases, however, the information from multiple techniques, allows us to more accurately identify the nature of these materials and to carry out appropriate complementary ex situ measurements to aid in the analysis. This and similar setups therefore offer a way to more quickly and accurately observe reaction pathways within a catalyst, which may for example, result in the deactivation of the material by different routes to those observed previously. Additionally, the specific combination of these techniques with on-line mass spectrometry, allows us to monitor the activity of the catalyst surface and here observe that different catalytic mechanisms may occur during different stages of the redox process. Therefore this setup should allow for the observation of many novel variations in a catalyst’s reactivity, leading to the improvement of current and development of new materials. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Systemic modelling and computational physiology: The application of Bond Graph boundary conditions for 3D cardiovascular models

This paper presents an application of Bond Graphs in physiological modelling. In this work, a Bond Graph model is utilised as boundary condition for a detailed model of an idealized mitral valve. Applications of this type fit within the framework described by the “Virtual Physiological Human” initiative. This supports the integration of physical, mechanical and biochemical models encompassing a range of different length and time scales to obtain predictive models of the human body. Because 3D detailed modelling and simulation is computationally intensive, a 3D computational model of a whole biological system is, by today’s standards, impossible to achieve. Due to their unique multi-physics nature of internal coherence, Bond Graphs are particularly suited to biological applications and can be coupled to 3D models and lumped parameter models. A specific application in cardiovascular modelling is demonstrated by focusing on a specific example; a 3D model of the mitral valve coupled to a lumped parameter model of the left ventricle.     

Capillary flow of liquid pitch

The capillary flow of liquid pitch into a granular coke bed has been theoretically investigated. An equation relating the flow rate with temperature has been derived considering the pitch as a Newtonian liquid. For a given coke granulometry, the wetting angle and the viscosity of the pitch material are the most important factors governing its flow properties. A comparison with experimental flow measurements indicates that some pitches penetrate into the granular coke bed according to the developed equation of flow.     

Biocontrol of Listeria monocytogenes in a model cultured milk (lben) by in situ bacteriocin production from Lactococcus lactis ssp. lactis

Bacteriocin‐producing (Bac⁺) Lactococcus lactis ssp. lactis CCMM/IAV/BK1 isolated from traditional lben was used in the preparation of lben from pasteurized milk to assess its potential inhibitory activity against Listeria monocytogenes ATCC 7644. Production of bacteriocin (arbitrary units, AU) in MRS broth fortified with yeast extract (MRSY) in a fermentor under controlled and uncontrolled pH conditions was also investigated. This Bac⁺ strain yielded about 35 times more bacteriocin when the pH was maintained constant at 6.5 than under varying pH conditions. To test the effect of in situ bacteriocin production against L. monocytogenes, lben was made from cow's milk artificially contaminated with approximately 10⁷ cfu/mL and fermented with a mixed mesophilic starter culture consisting of the lactococcal Bac⁺ organism and Lc. lactis ssp. lactis biovar diacetylactis 66, a diacetyl‐producing strain, in a ratio of 1 : 1. Numbers of L. monocytogenes were monitored during fermentation and storage of lben at refrigeration temperature (c. 7°C) for up to 6 days. Performances of the Bac⁺ starter were compared to those of an isogenic Bac^? derivative strain obtained from the Bac⁺ starter by curing with ethidium bromide. The results showed that the amount of L. monocytogenes decreased to below the detectable level in a 1‐mL sample within 24 h of storage at 7°C in lben fermented with the Bac⁺ starter culture. On the contrary, L. monocytogenes survived for 6 days of storage at 7°C in lben made with the Bac^? starter. The Bac⁺ wild strain of the starter studied could be adequately used to produce lben or similar indigenous fermented milks of improved hygienic quality on an industrial scale. Alternatively, it could be used as an adjunct in minimally processed products or in products obtained from raw milk to add a safety factor.     

Evaluation of two mutliscale models for the simulation of cross-die forming of Dual Phase (DP) steels

Two micro-macro modelling approaches, one based on crystal plasticity and the other on a Mori-Tanaka mean-field model, are presented and used for the simulation of forming operations on dual phase (DP) steels. The material parameters are determined based on bending-unbending experiments while deep-drawing with a cross-shaped die is simulated based on user-defined material laws (UMAT) in the ABAQUS finite element code. It is demonstrated that accurate predictions would require a combination of both modelling approaches.     

总体规划或是一种控制方法？——蒙特利尔城市地下空间开发案例

我们会经常提到利用地下空间的优点,以及除公共设施以外地下空间作为其他用途时的不便,甚至是地下空间的隧道施工方法。但遗憾的是,我们很少提到地下空间的规划,也几乎从来没提到过地下空间开发的制度措施。除了蒙特利尔,也许只有日本使用规章制度对地下空间用途逐层地实行管理。最近,上海编制了第一个关于地下空间的规章,成为中国首个采取类似措施的城市。新的规章第一次明确了地下空间的定义,并且对土地审批和所有权注册等事项进行了说明。上海决定给城市所有区域的地下空间编制一个总体规划,成为中国在该领域的先行者．     

A classification of methods for efficient power amplification of signals

This paper presents a classification of methods that have been proposed to address nonlinear power amplification of highly fluctuating signals in telecommunications. The classification proposed uses a tree-like representation wherein each branch refers to a group of methods that all have a common characteristic. By virtue of this representation, each node corresponds to a test used to discriminate between different methods. From top to bottom, these tests are “What is the target of the method?,” Is the method downward-compatible?,” “Is the bit error rate degraded?,” “Is there a useful data rate loss?,” and “Does the method require changes in the amplification function?” By collating all these requirements, an original classification is proposed that is open enough to allow new methods to be added. It only concerns methods located either only at the transmitter or at both transmitter and receiver. The context of this study generally concerns multicarrier signals (especially orthogonal frequency division modulation) but can be applied to any multiplex of modulated signals.