Electroweak Symmetry Breaking without a Higgs Boson at the LHC

We present two studies into strong symmetry breaking scenarios at the LHC. The first case is a study into vector boson scattering at ATLAS. This uses the framework of the Electroweak Chiral Lagrangian with Pade unitarisation to generate possible signal scenarios. Signals could be observed with an integrated luminosity of 30 fb^{-1}. Secondly a search for the technirho, rho_{TC}, at CMS is presented, within the Technicolour ``Straw Man'' model. 5 sigma discovery is possible starting from 4 fb^{-1}.Comment: 4 pages, to appear in the proceedings of 42st Rencontres de Moriond on QCD and Hadronic interactions, La Thuile, Aosta Valley, Italy, 17-24 Mar 200

A mechanistic explanation linking adaptive mutation, niche change, and fitness advantage for the Wrinkly Spreader

Experimental evolution studies have investigated adaptive radiation in static liquid microcosms using the environmental bacterium Pseudomonas fluorescens SBW25. In evolving populations a novel adaptive mutant known as the Wrinkly Spreader arises within days having significant fitness advantage over the ancestral strain. A molecular investigation of the Wrinkly Spreader has provided a mechanistic explanation linking mutation with fitness improvement through the production of a cellulose-based biofilm at the air-liquid interface. Colonisation of this niche provides greater access to oxygen, allowing faster growth than that possible for non-biofilm—forming competitors located in the lower anoxic region of the microcosm. Cellulose is probably normally used for attachment to plant and soil aggregate surfaces and to provide protection in dehydrating conditions. However, the evolutionary innovation of the Wrinkly Spreader in static microcosms is the use of cellulose as the matrix of a robust biofilm, and is achieved through mutations that deregulate multiple diguanylate cyclases leading to the over-production of cyclic-di-GMP and the stimulation of cellulose expression. The mechanistic explanation of the Wrinkly Spreader success is an exemplar of the modern evolutionary synthesis, linking molecular biology with evolutionary ecology, and provides an insight into the phenomenal ability of bacteria to adapt to novel environments

Getting Wrinkly Spreaders to demonstrate evolution in schools

Understanding evolution is crucial to modern biology,but most teachers would assume that practical demonstrations of evolution in school laboratories are unfeasible. However, perhaps they have not heard of ‘evolution in a test tube’ and how Wrinkly Spreaders can form the basis for both practical demonstrations of bacterial evolution and further work

Neural systems supporting navigation

Highlights: • Recent neuroimaging and electrophysiology studies have begun to shed light on the neural dynamics of navigation systems. • Computational models have advanced theories of how entorhinal grid cells and hippocampal place cells might serve navigation. • Hippocampus and entorhinal cortex provide complementary representations of routes and vectors for navigation. Much is known about how neural systems determine current spatial position and orientation in the environment. By contrast little is understood about how the brain represents future goal locations or computes the distance and direction to such goals. Recent electrophysiology, computational modelling and neuroimaging research have shed new light on how the spatial relationship to a goal may be determined and represented during navigation. This research suggests that the hippocampus may code the path to the goal while the entorhinal cortex represents the vector to the goal. It also reveals that the engagement of the hippocampus and entorhinal cortex varies across the different operational stages of navigation, such as during travel, route planning, and decision-making at waypoints

Solving the detour problem in navigation: a model of prefrontal and hippocampal interactions.

Adapting behavior to accommodate changes in the environment is an important function of the nervous system. A universal problem for motile animals is the discovery that a learned route is blocked and a detour is required. Given the substantial neuroscience research on spatial navigation and decision-making it is surprising that so little is known about how the brain solves the detour problem. Here we review the limited number of relevant functional neuroimaging, single unit recording and lesion studies. We find that while the prefrontal cortex (PFC) consistently responds to detours, the hippocampus does not. Recent evidence suggests the hippocampus tracks information about the future path distance to the goal. Based on this evidence we postulate a conceptual model in which: Lateral PFC provides a prediction error signal about the change in the path, frontopolar and superior PFC support the re-formulation of the route plan as a novel subgoal and the hippocampus simulates the new path. More data will be required to validate this model and understand (1) how the system processes the different options; and (2) deals with situations where a new path becomes available (i.e., shortcuts)

New insights into the effects of several environmental parameters on the relative fitness of a numerically dominant class of evolved niche specialist

Adaptive radiation in bacteria has been investigated using Wrinkly Spreaders (WS), a morphotype which colonises the air-liquid (A-L) interface of static microcosms by biofilm formation with a significant fitness advantage over competitors growing lower down in the O2-limited liquid column. Here, we investigate several environmental parameters which impact the ecological opportunity that the Wrinkly Spreaders exploit in this model system. Manipulation of surface area/volume ratios suggests that the size of the WS niche was not as important as the ability to dominate the A-L interface and restrict competitor growth. The value of this niche to the Wrinkly Spreaders, as determined by competitive fitness assays, was found to increase as O2 flux to the A-L interface was reduced, confirming that competition for O2 was the main driver of WS fitness. The effect of O2 on fitness was also found to be dependent on the availability of nutrients, reflecting the need to take up both for optimal growth. Finally, the meniscus trap, a high-O2 region formed by the interaction of the A-L interface with the vial walls, was also important for fitness during the early stages of biofilm formation. These findings reveal the complexity of this seemingly simple model system and illustrate how changes in environmental physicality alter ecological opportunity and the fitness of the adaptive morphotype

An experimental investigation of silicon wafer surface roughness and its effect on the full strength of plated metals

Plated silicon wafers with surface roughness ranging from 0.4 to 130 microinches were subjected to tensile pull strength tests. Electroless Ni/electroless Cu/electroplated Cu and electroless Ni/electroplated Cu were the two types of plate contacts tested. It was found that smoother surfaces had higher pull strength than rougher, chemically etched surfaces. The presence of the electroless Cu layer was found to be important to adhesion. The mode of fracture of the contact as it left the silicon was studied, and it was found that in almost all cases separation was due to fracture of the bulk silicon phase. The correlation between surface roughness and mode of contact failure is presented and interpreted

Evaluation of an online educational tool designed to reduce stress and boost well-being for people living with an ileostomy : a framework analysis

Ileostomies, in which the small intestine is re-directed out of a stoma in the stomach so that waste is collected using a bag, are using to treat conditions such as bowel cancer and Inflammatory Bowel Disease. Previous research has shown that life with an ileostomy can be challenging. In our own previous work, we piloted an Online Educational Tool (OET) designed to reduce stress and boost well-being in people living with an ileostomy. The current study utilised the qual-itative method framework analysis in order to evaluate the effectiveness of our OET. We asked nine OET users questions about their experience of using the tool and the impact it may have had on their lives. Feedback was generally positive. Participants described facilitators and barriers for remaining engaged, and discussed a wide range of elements which were successful or unsuccessful. Stress levels were generally reduced and well-being boosted; participants gave examples of how this played out for them. Feelings about whether the impact of the tool would last were mixed. There was one participant who felt the tool was not inclusive enough and too repetitive. Findings from this study add weight to previous findings that the OET was successful in its aims

An online educational tool to promote psychological well-being, optimism, and coping self-efficacy among people living with an ileostomy : a pilot study

We assessed an online educational tool designed for people living with an ileostomy. Thirty-nine participants took part in a 10-week online educational tool, which included elements such as happiness profiling, understanding stress and coping, utilising social support, mindfulness skills, and emotional intelligence training. Participants completed questionnaires to assess the effects of the online educational tool on well-being, optimism, and coping self-efficacy at Time 1 (baseline), Time 2 (after the intervention), and Time 3 (three months after completing the online educational tool). Psychological well-being, optimism, use of problem-focused coping self-efficacy, and stop unpleasant emotions and thoughts coping self-efficacy were significantly higher, with large effect sizes, at both Time 2 and Time 3, than Time 1. The online educational tool appears to be a promising time and cost effective method of promoting positive outcomes, although additional testing is required before it could be used in conjunction with existing healthcare treatment