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121.
Arbuscular mycorrhizal fungal (AMF) colonisation of plant roots is one of the most ancient and widespread interactions in ecology, yet the systemic consequences for plant secondary chemistry remain unclear. We performed the first metabolomic investigation into the impact of AMF colonisation by Rhizophagus irregularis on the chemical defences, spanning above- and below-ground tissues, in its host-plant ragwort (Senecio jacobaea). We used a non-targeted metabolomics approach to profile, and where possible identify, compounds induced by AMF colonisation in both roots and shoots. Metabolomics analyses revealed that 33 compounds were significantly increased in the root tissue of AMF colonised plants, including seven blumenols, plant-derived compounds known to be associated with AMF colonisation. One of these was a novel structure conjugated with a malonyl-sugar and uronic acid moiety, hitherto an unreported combination. Such structural modifications of blumenols could be significant for their previously reported functional roles associated with the establishment and maintenance of AM colonisation. Pyrrolizidine alkaloids (PAs), key anti-herbivore defence compounds in ragwort, dominated the metabolomic profiles of root and shoot extracts. Analyses of the metabolomic profiles revealed an increase in four PAs in roots (but not shoots) of AMF colonised plants, with the potential to protect colonised plants from below-ground organisms.  相似文献   
122.
Neural Computing and Applications - Mobile robots such as unmanned aerial vehicles (drones) can be used for surveillance, monitoring and data collection in buildings, infrastructure and...  相似文献   
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124.
The Persian Gulf War resulted in injuries of US Coalition personnel by fragments of depleted uranium (DU). Fragments not immediately threatening the health of the individuals were allowed to remain in place, based on long-standing treatment protocols designed for other kinds of metal shrapnel injuries. However, questions were soon raised as to whether this approach is appropriate for a metal with the unique radiological and toxicological properties of DU. The Armed Forces Radiobiology Research Institute (AFRRI) is investigating health effects of embedded fragments of DU to determine whether current surgical fragment removal policies remain appropriate for this metal. These studies employ rodents implanted with DU pellets as well as cultured human cells exposed to DU compounds. Results indicate uranium from implanted DU fragments distributed to tissues far-removed from implantation sites, including bone, kidney, muscle, and liver. Despite levels of uranium in the kidney that were nephrotoxic after acute exposure, no histological or functional kidney toxicity was observed. However, results suggest the need for further studies of long-term health impact, since DU was found to be mutagenic, and it transformed human osteoblast cells to a tumorigenic phenotype. It also altered neurophysiological parameters in rat hippocampus, crossed the placental barrier, and entered fetal tissue. This report summarizes AFRRI's depleted uranium research to date.  相似文献   
125.
BACKGROUND: Mycelium of the medicinal mushroom shiitake, Lentinus edodes, is a potential source for production of the blood cholesterol reducing compound eritadenine. To increase the mycelial biomass and in turn the production of eritadenine, a potential growth promoting substance in the form of a water extract of distillers dried grains with solubles (DDGS) was added to the culture media. RESULTS: The hot water extract of DDGS was shown to considerably increase the growth of shiitake mycelia in bioreactor cultivations; the mycelial yield was 2–3 times higher than in the control, and the highest final biomass concentration obtained was 3.4 g L?1. Further, by using shake flask cultures as inoculums the bioreactor cultivation time could be reduced by 1 week for some of the experiments. The highest final titer of eritadenine in the present study was 25.1 mg L?1, which was about 2 times higher than in the control, and was also obtained when a water extract of DDGS was added to the culture medium. CONCLUSION: It was demonstrated that a water extract of DDGS promoted the growth of shiitake mycelia in bioreactor cultivations, along with enhanced eritadenine production. Copyright © 2012 Society of Chemical Industry  相似文献   
126.
Articular cartilage is a poroelastic (biphasic) material with a complex deformation behavior, which can be considered elastic–viscoelastic. In this article, articular porcine cartilage is tested in vitro using dynamic nanoindentation and is analyzed using the frequency domain. The testing and data analysis are presented as a function of the strain rate and frequency, which allows for the results to be compared for various load amplitudes over the same frequency range. In addition, a new approach to correct the contact area during dynamic nanoindentation is presented and the effects of sample freezing on the mechanical properties are also discussed.  相似文献   
127.
A continuum theory of surface growth is applied to the mechanical modeling of cell motility. The theory relies on a decomposition of the motion into deformation- and growth-inducing parts. A non-dissipative constitutive relation is adopted and expressed exclusively in terms of the current configuration. The resulting model is used in the simulation of a network of actin filaments, and a simple one-dimensional example is included to showcase its predictive capacity.  相似文献   
128.
An online yarn tension sensing and control device has been designed and developed. The system was specifically devised for use in a direct cabling machine, wherein yarn tension in the spindle or pot yarn is highly critical and dictates the uniformity of the cabled yarn. Since a balloon formed by the creel yarn always encompasses the pot yarn in a direct cabling machine, yarn tension measurement using a wired sensor is far-fetched. Accordingly, a wireless yarn tension sensor was developed to address this problem and perform online yarn tension measurement. The wireless sensor can be used as an active monitoring tool for measuring online yarn tension in both component yarns, while the closed loop control system replaces passive yarn brakes used in the current direct cabling machines and executes a control mechanism that can control yarn tension adaptively. The device uses Micro-Electro-Mechanical Systems (MEMS) technology with radio frequency (RF) transmission to effectively carry out dynamic online measurement. The control system in conjunction with the wireless sensor ensures equal tension in the component yarns, resulting in the formation of a uniform cabled yarn with equal lengths of both yarns.  相似文献   
129.
The contemporary cotton spinning mill is home to modern machinery capable of generating a plethora of data. This data comes in the form of online data, which is real-time data created by the processing machinery, and offline data, which is created via laboratory testing of samples. This paper describes a study which applied statistical techniques to the two data sets. One came from an actual open-end spinning plant. The other was created in a laboratory environment. This analysis served to discover trends within this data sample and to determine the optimal data use for the cotton spinning industry. In addition, the paper presents a perspective into the current state of data management in the cotton spinning industry obtained by visiting an assortment of active spinning mills.  相似文献   
130.
While nickel has been known for centuries as a material for various uses, including the Ni-Fe expansion alloys that were developed around 1896, the history of the solid-solution-strengthened nickel-based alloys begins with the development of the Ni-Cualloy Monel® in 1996. Since that time many other alloys have been developed containing other elements and possessing significantly different corrosion resistance. These developments have also been aided by developments in the metallurgical processing of nickel alloys. This paper will discuss the major nickel alloy developments that have allowed and expanded the use of these alloys in the chemical processing industry.  相似文献   
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