The Simultaneous Repression of CCR and CAD, Two Enzymes of the Lignin Biosynthetic Pathway, Results in Sterility and Dwarfism in Arabidopsis thaliana

Cinnamoyl CoA reductase(CCR)and cinnamyl alcohol dehydrogenase(CAD)catalyze the last steps of monolignol biosynthesis.In Arabidopsis,one CCR gene(CCR1,At1g15950)and two CAD genes(CAD C At3g19450 and CAD D At4g34230)are involved in this pathway.A triple cad c cad d ccr1 mutant,named ccc,was obtained.This mutant displays a severe dwarf phenotype and male sterility.The lignin content in ccc mature stems is reduced to 50% of the wild-type level.In addition,stem lignin structure is severely affected,as shown by the dramatic enrichment in resistant inter-unit bonds and incorporation into the polymer of monolignol precursors such as coniferaldehyde,sinapaldehyde,and ferulic acid.Male sterility is due to the lack of lignification in the anther endothecium,which causes the failure of anther dehiscence and of pollen release.The ccc hypolignified stems accumulate higher amounts of flavonol glycosides,sinapoyl malate and feruloyl malate,which suggests a redirection of the phenolic pathway.Therefore,the absence of CAD and CCR,key enzymes of the monolignol pathway,has more severe consequences on the phenotype than the individual absence of each of them.Induction of another CCR(CCR2,At1g80820)and another CAD(CAD1,At4g39330)does not compensate the absence of the main CCR and CAD activities.This lack of CCR and CAD activities not only impacts lignification,but also severely affects the development of the plants.These consequences must be carefully considered when trying to reduce the lignin content of plants in order to facilitate the lignocellulose-to-bioethanol conversion process.     

Literacy Sponsorship of the “My Online Friends” Discussion Board: Competing and Complementary Relationships

This article argues that we need to consider the complementary and competing relationships among the multiple types of sponsors of digital literacies. As we explore not just what people are reading and writing online, but also what sponsors fuel their motivations for doing so, we will have a better understanding of the constraints that accompany specific digital literacy opportunities, as well as what motivates individuals or groups to change their online reading and writing given these constraints.In this article, I discuss the relationships among the three commercial sponsors and one religious sponsor of the “My Online Friends” (MOF) discussion board, a group composed of approximately 120 women who are all members of the LDS, or Mormon, church. On the MOF discussion board, intersections among sponsors affect the women's establishment of group and individual identities and their use of relational literacy. In response to commercial sponsors’ coding and rules of use, which constrained the MOF women's religious and individual identity construction, the MOF women acted to change the commercial sponsorship of their spaces, yet they also adopted subject positions initially provided by commercial sponsors.     

用不锈钢包裹建筑——可持续性幕墙和屋面

恰当地选择和维护不锈钢,可延用几个世纪而保持其吸引力.在历经如此之长的使用寿命后,不锈钢具有的高废钢价值和低腐蚀率,保证它使用期结束后可以回收再利用,且回收利用率非常之高.本文阐释了不锈钢在可持续屋面和幕墙工程上的运用.     

Are online discussions enough to constitute communities of practice in professional domain? A case study of ergonomics’ practice in France

The goal of our research is to characterise how online discussions may provide support to the construction of a Virtual Community of Practice, as a way to develop a profession. To do so, we investigate the functions (sharing information, resources or experience) and the nature of knowledge (e.g. methodology and trends of ergonomics) exchanged on Ergoliste, a French-speaking online mailing list dedicated to ergonomics, as well as the status of participants. Our results reveal that the list has both informative and formative functions as it deals with sharing/seeking information, resources and experience, mainly between experts and novices in ergonomics, exchanging about situated and circumstantiated aspects of practices. Finally, these results are complemented by interviews with list participants which on the one hand confirm the main functions of the list and, on the other hand, reveal divergence in the perception that list participants belonging to a “community” structured only around this list. This research opens some prospects for more longitudinal investigations of the contents of the list, to analyse more deeply how the list can be viewed as an efficient tool to co-elaborate knowledge about ergonomics and its development.     

Compositional and Structural Studies of the Major and Minor Components in Three Cameroonian Seed Oils by GC–MS,ESI-FTICR-MS and HPLC

The lipid components of three Cameroonian seed oils, ke tchock (Aframomum arundinaceum), njangsa (Ricinodendron heudelotii) and calabash nutmeg (Monodora myristica), have been investigated. Gas chromatography (GC)–mass spectrometry (MS) fatty acid (FA) analysis showed M. myristica seed oil to be dominated by linoleic (49.29%) and oleic (37.17%) acids; R. heudelotii was mainly linoleic (58.73%), followed by stearic (15.00%) and oleic (14.21%) acids; A. arundinaceum was predominantly oleic (65.76%) and palmitic (20.36%) acids. Electrospray ionization (ESI)-Fourier transform ion cyclotron resonance (FTICR)-MS analysis showed seven major triacylglycerol (TAG) classes for M. myristica, with C54:5, C54:4 and C54:6 dominating. R. heudelotii had eight major TAG classes with C54:8, C54:7 and C54:6 being most abundant. A. arundinaceum also had eight major TAG classes with C52:2, C54:3 and C50:2 dominating. ¹³C nuclear magnetic resonance (NMR) analysis of the TAGs showed that both sn-1,3 and sn-2 positions were predominantly occupied by linoleoyl and oleoyl chains. High-performance liquid chromatography (HPLC) fluorescence detector (FLD) analysis showed that M. myristica contained only α- and β-tocopherols (195.40 and 73.95 μg/g, respectively), R. heudelotii contained mainly γ-tocopherol (289.40 μg/g), and A. arundinaceum had mainly γ- and β-tocopherols (236.78 and 124.93 μg/g, respectively). GC–MS analysis of the unsaponifiable matter showed that β-sitosterol was the most abundant phytosterol in all three seed oils. The absolute amounts of 4-desmethylsterols were 196.15, 608.71 and 362.15 μg/g for M. myristica, R. heudelotii and A. arundinaceum seed oils, respectively. These compositional and structural studies provide justification for the use of all three seed oils in food products.     

Microfluidics for medical diagnostics and biosensors

This article reviews the recent development in microfluidics for medical diagnostics and integrations with biosensors. Diagnostic and sensing applications have been the focus of much of the development of the micro-Total-Analysis-Systems (MicroTAS), and have recently enjoyed further development in new fabrication technologies, integrations, and utilities in field- and medical-applications. The challenges for these applications have been to reduce cost, to meet the sensitivity requirements while providing throughput and speed, and to expand the repertoire of applications. This review focuses mostly on new developments in the last 5–10 years in materials development, chip architecture and integration, different sensing modes that can be used in conjunction with microfluidics, and new applications that have emerged or have been demonstrated; it also aims to point out where future research can be directed to in these areas.     

Anatomy of the 2009 Fiordland earthquake (Mw 7.8), South Island, New Zealand

We have analyzed the July 15, 2009, Fiordland earthquake (Mw 7.8). which occurred in the southwestern part of the South Island of New Zealand. This thrust-related earthquake in the southern Fiordland subduction zone is the largest New Zealand earthquake in the past 80 years. We have con-strained a rupture model for this earthquake using coseismic offsets derived from the continuous geodetic network (Global Positioning System) of the New Zealand Institute of Geological and Nuclear Sciences (GNS Science). Our analysis concludes that this earthquake significantly increased the Coulomb stress on the overriding plate, particularly on the offshore portion of the Alpine fault.2011, China University of Geosciences (Beijing) and Peking University. Production and hosting byElsevier B.V. All rights reserved.     

麦肯锡香港分公司办公室

正为满足这所顾问公司的使用需求,OMA设计的麦肯锡香港分公司办公室提供了更私密的空间,增加员工的合作性及归属感。OMA在设计新办公室的时候所遇到的设计问题是:如何重新考虑空间运用,推动麦肯锡的公司文化?OMA的设计师从黑色条码图案获得灵感,来设计新办公室的布局——各个功能空间组织成横条形状,并列在整个办公室里。新设计的办公室摆脱了传统写字楼的模式,     

“I'm a Visual Learner so I like this”: Investigating Student and Faculty Tutorial Preferences

Online tutorials are useful for reinforcing information literacy concepts addressed in library instruction. A wide range of tutorial types cater to different learning styles and feature varying levels of interactivity. In this study, students and faculty reported experiences using two types of tutorials teaching basic search strategies—an interactive tutorial, and a video tutorial. Although both groups favored the video, faculty were split about which tutorial they would rather assign, a discrepancy suggesting questions about how tutorial developers should balance user preferences with learning needs. These findings provide valuable insights for librarians and instructional designers considering creating information literacy tutorials.