Observation of a new \chi_b state at ATLAS and a new \Xi_b baryon at CMS

Two recent observations of new b hadrons in pp collisions at \sqrt{s} = 7 TeV at the Large Hadron Collider (LHC) are presented. The ATLAS collaboration has observed a new state in radiative transitions to \Upsilon(1S) and \Upsilon(2S) and interprets this as the first observation of the \chi_b(3P) states. The CMS collaboration has observed a new b baryon decaying to \Xi_b-\pi+ (plus charge conjugates). This is interpreted as a neutral J^P = 3/2^+ \Xi_b* baryon.Comment: 10 pages, 6 figures, Presented at Flavor Physics and CP Violation (FPCP 2012), Hefei, China, May 21-25, 201

Disabilty in Older Adults with Depression

Depression is a leading cause of disability among older adults which can change the scope of daily life for older adults and threaten their ability to live independently in the community. This dissertation explored task disability in older adults with depression in three studies. A unique aspect of the studies was the assessment of disability through performance-testing. The first study examined task disability patterns in a sample of older adults with depression being treated as inpatients (n = 60) or outpatients (n = 59). Rasch analysis revealed that the degree of disability for task domains (functional mobility [FM], basic activities of daily living [BADL], instrumental activities of daily living [IADL] with a greater physical component [IADL-physical], and IADL with a greater cognitive component [IADL-cognitive]), and task items, was different for older women whose depression resulted in inpatient versus outpatient treatment. With the same sample, the second study examined the impact of information processing speed on task disability. The patients were separated into groups by speed of processing (slower patients, n = 76; faster patients, n = 23) based on their performance on the Trail Making Test - B. Speed of processing was associated with severity of depression and both depression and slower speed of processing interfered more with effortful processing tasks (i.e., IADL-cognitive and IADL-physical) and less with tasks requiring automatic processing (i.e. FM). The third study compared physician rated disability on the Global Assessment of Function (GAF) Scale with performance-disability observed on the Performance Assessment of Self-Care Skills (PASS) in a hospitalized community-based sample separated into subgroups by readmission status (readmit patients, n = 15; non-readmit patients, n = 43). There was a lack of concordance between the measures with only the GAF Scale showing significant reduction in disability at discharge. Findings from these studies suggest that for older adults with depression, there may be sentinel tasks which are disability indicators and those tasks may differ based on speed of processing. The lack of concordance between the disability measures suggests the need for consideration of performance-based testing of daily life tasks as a component of usual care

Regulation of Microtubule Dynamics in Axon Regeneration: Insights from C. elegans.

The capacity of an axon to regenerate is regulated by its external environment and by cell-intrinsic factors. Studies in a variety of organisms suggest that alterations in axonal microtubule (MT) dynamics have potent effects on axon regeneration. We review recent findings on the regulation of MT dynamics during axon regeneration, focusing on the nematode Caenorhabditis elegans. In C. elegans the dual leucine zipper kinase (DLK) promotes axon regeneration, whereas the exchange factor for Arf6 (EFA-6) inhibits axon regeneration. Both DLK and EFA-6 respond to injury and control axon regeneration in part via MT dynamics. How the DLK and EFA-6 pathways are related is a topic of active investigation, as is the mechanism by which EFA-6 responds to axonal injury. We evaluate potential candidates, such as the MT affinity-regulating kinase PAR-1/MARK, in regulation of EFA-6 and axonal MT dynamics in regeneration

Highly efficient optogenetic cell ablation in C. elegans using membrane-targeted miniSOG.

The genetically encoded photosensitizer miniSOG (mini Singlet Oxygen Generator) can be used to kill cells in C. elegans. miniSOG generates the reactive oxygen species (ROS) singlet oxygen after illumination with blue light. Illumination of neurons expressing miniSOG targeted to the outer mitochondrial membrane (mito-miniSOG) causes neuronal death. To enhance miniSOG's efficiency as an ablation tool in multiple cell types we tested alternative targeting signals. We find that membrane targeted miniSOG allows highly efficient cell killing. When combined with a point mutation that increases miniSOG's ROS generation, membrane targeted miniSOG can ablate neurons in less than one tenth the time of mito-miniSOG. We extend the miniSOG ablation technique to non-neuronal tissues, revealing an essential role for the epidermis in locomotion. These improvements expand the utility and throughput of optogenetic cell ablation in C. elegans

Kaluza-Klein Theory without Extra Dimensions: Curved Clifford Space

A theory in which 16-dimensional curved Clifford space (C-space) provides a realization of Kaluza-Klein theory is investigated. No extra dimensions of spacetime are needed: "extra dimensions" are in C-space. It is shown that the covariant Dirac equation in C-space contains Yang-Mills fields of the U(1)xSU(2)xSU(3) group as parts of the generalized spin connection of the C-space.Comment: 15 pages; References added, typos correcte