A novel role for the TIR domain in association with pathogen-derived elicitors

Plant innate immunity is mediated by Resistance (R) proteins, which bear a striking resemblance to animal molecules of similar function. Tobacco N is a TIR-NB-LRR R gene that confers resistance to Tobacco mosaic virus, specifically the p50 helicase domain. An intriguing question is how plant R proteins recognize the presence of pathogen-derived Avirulence (Avr) elicitor proteins. We have used biochemical cell fraction and immunoprecipitation in addition to confocal fluorescence microscopy of living tissue to examine the association between N and p50. Surprisingly, both N and p50 are cytoplasmic and nuclear proteins, and N's nuclear localization is required for its function. We also demonstrate an in planta association between N and p50. Further, we show that N's TIR domain is critical for this association, and indeed, it alone can associate with p50. Our results differ from current models for plant innate immunity that propose detection is mediated solely through the LRR domains of these molecules. The data we present support an intricate process of pathogen elicitor recognition by R proteins involving multiple subcellular compartments and the formation of multiple protein complexes. © 2007 Burch-Smith et al

Kronian Magnetospheric Reconnection Statistics Across Cassini's Lifetime

Magnetic reconnection is a fundamental physical process in planetary magnetospheres, in which plasma can be exchanged between the solar wind and a planetary magnetosphere, and material can be disconnected and ultimately lost from a magnetosphere. Magnetic reconnection in a planetary magnetotail can result in the release of plasmoids downtail and dipolarizations planetward of an x-line. The signatures of these products include characteristic deflections in the north-south component of the magnetic field which can be detected by in-situ spacecraft. These signatures have been identified by eye, semi-automated algorithms, and recently machine learning methods. Here, we apply statistical analysis to the most thorough catalogue of Kronian magnetospheric reconnection signatures created through machine learning methods to improve understanding of magnetospheric evolution. This research concludes that no quasi-steady position of the magnetotail x-line exists within 70 RS. This research introduces prediction equations to estimate the distribution of duration of plasmoid passage over the spacecraft (N = 300∆t −1.3 , bin width = 1 min) and north-south field deflection (N = 52∆B −2.1 θ , bin width = 0.25 nT) expected to be identified by an orbiting spacecraft across a year of observations. Furthermore, this research finds a local time asymmetry for reconnection identifications, with a preference for dusk-side over dawn-side. This may indicate a preference for Vasyliunas style reconnection over Dungey style for Saturn. Finally, through these distributions, the reconnection rate of Saturn’s magnetotail can be estimated as 3.22 reconnection events per day, with a resulting maximum mass loss from plasmoids of 44.87 kg s−1 on average, which is comparable with the magnetospheric mass loading from Enceladus (8-250 kg s−1 )

Turning to art as a positive way of living with cancer: A qualitative study of personal motives and contextual influences

Why do some women turn to creative art-making after a diagnosis of cancer? Eleven women provided qualitative accounts that were analyzed following guidelines for interpretative phenomenological analysis (IPA). Some described taking up artistic leisure activities initially in order to manage emotional distress. Others emphasized their need for positive well-being, taking up art to experience achievement and satisfaction, to regain a positive identity, and to normalize family dynamics in the context of living with cancer. Participants’ turn to art-making was facilitated by biographical and contextual factors, including pre-existing craft skills, long-standing personal values and coping philosophies, family role models for managing adversity, and the supportive encouragement of family and friends. Other research has acknowledged that positive lifestyle change and post-traumatic growth can occur after a cancer diagnosis, and this study reveals a multi-faceted process. The findings suggest a need for further research into the experiences that facilitate positive lifestyle change and subjective well-being among people who are living with cancer

Evaluation of pulp and paper making characteristics of elephant grass (Pennisetum purpureum Schum) and switchgrass (Panicum virgatum L.)

Shortage of conventional raw material for the pulp and paper products together with the increasing world demand for paper has renewed interest in non-wood fibres. Non-wood pulping capacity has been increasing steadily over the last decade. A lot of crops grown for biomass, like switchgrass (Panicum virgatum L.), are good examples of plants with potential for pulp production. Raw material chemical composition, kraft pulp yield and properties, and fibre characteristics of elephant grass or hybrid pennisetum (Pennisetum purpureum Schum. cv. SDPN3) and switchgrass (cv. Cave-in-Rock) were determined in an effort to evaluate them as raw materials for pulp and paper production. Elephant grass had α-cellulose and Klasson lignin contents of 45.6 and 17.7%, respectively. The respective values for switchgrass were 41.2 and 23.89 %. Pulp yields, following a mild kraft process, were 48 and 50% for switchgrass and elephant grass, respectively. The corresponding kappa numbers were 15.5 and 9.2. The weight-weighted fibre length averaged 1.32 mm. Pulp freeness was higher for switchgrass (330 mL) than for elephant grass (139 mL). Elephant grass had a burst index above 5.85 kP.m2 g-1. These characteristics demonstrate the suitability of both elephant grass and switchgrass for pulp production.Key words: Grass pulp, kraft pulping, non-wood fibre, elephant grass, switchgrass

Are sweet snacks more sensitive to price increases than sugar-sweetened beverages: analysis of British food purchase data

This is the final published version. Available from BMJ Publishing Group via the DOI in this record.The data for this study were purchased from Kantar Worldpanel but its use is restricted to the persons named in the purchase contract which forbids the users to share the data with other potential (unnamed on the contract) users. Data access requests should be directed to Kantar Worldpanel.Objectives Taxing sugar-sweetened beverages (SSBs) is now advocated, and implemented, in many countries as a measure to reduce the purchase and consumption of sugar to tackle obesity. To date, there has been little consideration of the potential impact that such a measure could have if extended to other sweet foods, such as confectionery, cakes and biscuits that contribute more sugar to the diet than SSBs. The objective of this study is to compare changes in the demand for sweet snacks and SSBs arising from potential price increases. Setting Secondary data on household itemised purchases of all foods and beverages from 2012 to 2013. Participants Representative sample of 32249 households in Great Britain. Primary and secondary outcome measures Change in food and beverage purchases due to changes in their own price and the price of other foods or beverages measured as price elasticity of demand for the full sample and by income groups. Results Chocolate and confectionery, cakes and biscuits have similar price sensitivity as SSBs, across all income groups. Unlike the case of SSBs, price increases in these categories are also likely to prompt reductions in the purchase of other sweet snacks and SSBs, which magnify the overall impact. The effects of price increases are greatest in the lowincome group. Conclusions Policies that lead to increases in the price of chocolate and confectionery, cakes and biscuits may lead to additional and greater health gains than similar increases in the price of SSBs through direct reductions in the purchases of these foods and possible positive multiplier effects that reduce demand for other products. Although some uncertainty remains, the associations found in this analysis are sufficiently robust to suggest that policies—and research—concerning the use of fiscal measures should consider a broader range of products than is currently the case.Department of Health in England Policy Research Programme (Policy Research Unit in Behaviour and HealthMedical Research Council (MRC

Subglacial swamps

peer-reviewedThe existence of both water and sediment at the bed of ice streams is well documented, but there is a lack of fundamental understanding about the mechanisms of ice, water and sediment interaction. We pose a model to describe subglacial water flow below ice sheets, in the presence of a deformable sediment layer. Water flows in a rough-bedded film; the ice is supported by larger clasts, but there is a millimetric water layer submerging the smaller particles. Partial differential equations describing the water film are derived from a description of the dynamics of ice, water and mobile sediment. We assume that sediment transport is possible, either as fluvial bedload, but more significantly by ice-driven shearing and by internal squeezing. This provides an instability mechanism for rivulet formation; in the model, downstream sediment transport is compensated by lateral squeezing of till towards the incipient streams. We show that the model predicts the formation of shallow, swamp-like streams, with a typical depth of the order of centimetres. The swamps are stable features, typically with a width of the order of tens to hundreds of metres.PUBLISHEDpeer-reviewe

Estimating the furrow infiltration characteristic from a single advance point

Management and control of surface irrigation, in particular furrow irrigation, is limited by spatio-temporal soil infiltration variability as well as the high cost and time associated with collecting intensive field data for estimation of the infiltration characteristics. Recent work has proposed scaling the commonly used infiltration function by using a model infiltration curve and a single advance point for every other furrow in an irrigation event. Scaling factors were calculated for a series of furrows at two sites and at four points down the length of the field (0.25 L, 0.5 L, 0.75 L and L). Differences in the value of the scaling factor with distance were found to be a function of the shape of the advance curves. It is concluded that use of points early in the advance results in a substantial loss of accuracy and should be avoided. The scaling factor was also strongly correlated with the furrow-wetted perimeter suggesting that the scaling is an appropriate way of both predicting and accommodating the effect of the hydraulic variability

Influence of effective stress and pore‐fluid pressure on fault strength and slip localization in carbonate slip zones

The presence of pressurized fluids influences the mechanical behaviour of faults. To test the roles of normal stress and fluid pressure on shear strength and localization behaviour of calcite gouges, we conducted a series of rotary‐shear experiments with pore‐fluid pressures up to 10.5 MPa and difference between normal stress and fluid pressure up to 11.2 MPa. Calcite gouges were sheared for displacements of 0.3 m to several meters at slip rates of 1 mm/s and 1 m/s. Drainage conditions in experiments were constrained from estimates of the hydraulic diffusivity. Gouges were found to be drained at 1 mm/s, but possibly partially undrained during sliding at 1 m/s. Shear strength obeys an effective‐stress law with an effective‐stress coefficient close to unity with a friction coefficient of c. 0.7 that decreases to 0.19 due to dynamic weakening. The degree of comminution and slip localization constrained from experimental microstructures depends on the effective normal stress. Slip localization in calcite gouges does not occur at low effective normal stress. The presence of pore fluids lowers the shear strength of gouges sheared at 1 mm/s and causes an accelerated weakening at 1 m/s compared to dry gouges, possibly due to enhanced subcritical crack growth and intergranular lubrication. Thermal pressurization occurs only after dynamic weakening when friction is generally low and relatively independent of normal stress and therefore unaffected by thermal pressurization. The experimental results are consistent with the view that the presence of pressurized fluid in carbonate‐bearing faults can facilitate earthquake nucleation

Gaussian bosonic synergy: quantum communication via realistic channels of zero quantum capacity

As with classical information, error-correcting codes enable reliable transmission of quantum information through noisy or lossy channels. In contrast to the classical theory, imperfect quantum channels exhibit a strong kind of synergy: there exist pairs of discrete memoryless quantum channels, each of zero quantum capacity, which acquire positive quantum capacity when used together. Here we show that this "superactivation" phenomenon also occurs in the more realistic setting of optical channels with attenuation and Gaussian noise. This paves the way for its experimental realization and application in real-world communications systems.Comment: 5 pages, 4 figures, one appendi