Stringent Phenomenological Investigation into Heterotic String Optical Unification

For the weakly coupled heterotic string (WCHS) there is a well-known factor of twenty conflict between the minimum string coupling unification scale, Lambda_H ~5x10^(17) GeV, and the projected MSSM unification scale, Lambda_U ~ 2.5x10^(16) GeV, assuming an intermediate scale desert (ISD). Renormalization effects of intermediate scale MSSM-charged exotics (ISME) (endemic to quasi-realistic string models) can resolve this issue, pushing the MSSM scale up to the string scale. However, for a generic string model, this implies that the projected Lambda_U unification under ISD is accidental. If the true unification scale is 5.0x10^(17) GeV, is it possible that illusionary unification at 2.5x10^(17) GeV in the ISD scenario is not accidental? If it is not, then under what conditions would the assumption of ISME in a WCHS model imply apparent unification at Lambda_U when ISD is falsely assumed? Geidt's "optical unification" suggests that Lambda_U is not accidental, by offering a mechanism whereby a generic MSSM scale Lambda_U < Lambda_H is guaranteed. A WCHS model was constructed that offers the possibility of optical unification, depending on the availability of anomaly-cancelling flat directions meeting certain requirements. This paper reports on the systematic investigation of the optical unification properties of the set of stringent flat directions of this model. Stringent flat directions can be guaranteed to be F-flat to all finite order (or to at least a given finite order consistent with electroweak scale supersymmetry breaking) and can be viewed as the likely roots of more general flat directions. Analysis of the phenomenology of stringent flat directions gives an indication of the remaining optical unification phenomenology that must be garnered by flat directions developed from them.Comment: standard latex, 18 pages of tex

Cosmetic Earnings Management in the Post-SOX Period: An Analysis of Entity Size

Cosmetic earnings management (CEM) takes place when income lies just beneath a benchmark (e.g., $2.98 billion) and management modestly enhances earnings to reach the goal (e.g.,$3.00 billion). U.S. studies show that CEM occurred prior to SOX but vanished afterward. Research on CEM after SOX, though, largely ignores the relationship between entity size and earnings management. This study tests for CEM post SOX but does so by separating the sample into quintiles based on entity size. While no evidence of CEM appears for the largest 80 percent of the company-years, significant CEM emerges within the quintile containing the smallest entities

MULTIVARIATE STATISTICAL ANALYSIS OF TERRESTRIAL INVERTEBRATE INDEX OF BIOTIC INTEGRITY

The Index of Biotic Integrity (IBI) is designed to measure the changes in ecological and environmental conditions as affected by human disturbances. In practice, the IBI is used in various ecological applications to detect divergence in biological integrity attributable to human actions. Last year during this conference, methodologies for developing an Avian Index of Biotic Integrity (A-IBI) were presented and discussed. The objective of this paper is to demonstrate the construction and statistical evaluation of a multi-metric terrestrial Invertebrate Index of Biotic Integrity (I-IBI) using the same multivariate statistical techniques. Canonical correlation analyses were utilized to select pertinent invertebrate metrics as impacted by vegetation and hydrology variables. The resulting invertebrate metrics were then ranked, according to a pre-specified scale of human disturbance, and the I-IBI scores were subsequently computed. The multivariate model, as well as the final I-IBI scores were statistically validated using independent temporal data sets. Furthermore, the sensitivity of I-IBI values was determined in order to access their reliability. The techniques are demonstrated using five years of invertebrate survey data collected from the terrestrial environments within the historic fifty-year floodplain of the Kootenai River in Northern Idaho

Enhancing Rural Manufacturers Competitiveness Through Design Automation For New Product Development

The competitiveness of third world manufacturing has placed pressure on U.S. manufacturers to create new products to survive.  Computer aided solid modeling and rapid prototyping technologies accelerate new product development, but rural manufacturers are often left behind.  This paper describes a cooperative venture between a state university and a federal agency to improve the new product development process of selected rural manufacturers by introducing them to leading-edge design automation technologies. Use of these tools allows better cross-functional communication among top management, marketing, designers, engineers, and manufacturing as they proceed through the new product creation process. Participating companies produced new product options, enhanced employment, and increased revenues

Tetrachloroethylene-contaminated drinking water and the risk of breast cancer.

We conducted a population-based case-control study to evaluate the relationship between cases of breast cancer and exposure to tetrachloroethylene (PCE) from public drinking water ( n = 258 cases and 686 controls). Women were exposed to PCE when it leached from the vinyl lining of water distribution pipes. The relative delivered dose was estimated using an algorithm that accounted for residential history, water flow, and pipe characteristics. Only small increases in breast cancer risk were seen among ever-exposed women either when latency was ignored or when 5 to 15 years of latency was considered. No or small increases were seen among highly exposed women either when latency was ignored or when 5 years of latency was considered. However, the adjusted odds ratios (ORs) were more increased for highly exposed women when 7 and 9 years of latency, respectively, were considered (OR 1.5 95% CI 0.5-4.7 and OR 2.3, 95% CI 0.6-8.8 for the 75th percentile, and OR 2.7, 95% CI 0.4-15.8 and OR 7.6, 95% CI 0.9-161.3 for the 90th percentile). The number of highly exposed women was too small for meaningful analysis when more years of latency were considered. Because firm conclusions from these data are limited, we recently undertook a new study with a large number of more recently diagnosed cases

Perchloroethylene-contaminated drinking water and the risk of breast cancer: additional results from Cape Cod, Massachusetts, USA.

In 1998 we published the results of a study suggesting an association between breast cancer and perchloroethylene (PCE; also called tetrachloroethylene) exposure from public drinking water. The present case-control study was undertaken to evaluate this association further. The cases were composed of female residents of eight towns in the Cape Cod region of Massachusetts who had been diagnosed with breast cancer from 1987 through 1993 (n = 672). Controls were composed of demographically similar women from the same towns (n = 616). Women were exposed to PCE when it leached from the vinyl lining of water distribution pipes from the late 1960s through the early 1980s. A relative delivered dose of PCE that entered a home was estimated using an algorithm that took into account residential history, water flow, and pipe characteristics. Small to moderate elevations in risk were seen among women whose exposure levels were above the 75th and 90th percentiles when 0-15 years of latency were considered (adjusted odds ratios, 1.5-1.9 for > 75th percentile, 1.3-2.8 for > 90th percentile). When data from the present and prior studies were combined, small to moderate increases in risk were also seen among women whose exposure levels were above the 75th and 90th percentiles when 0-15 years of latency were considered (adjusted odds ratios, 1.6-1.9 for > 75th percentile, 1.3-1.9 for > 90th percentile). The results of the present study confirm those of the previous one and suggest that women with the highest PCE exposure levels have a small to moderate increased risk of breast cancer

Activated Notch2 Signaling Inhibits Differentiation of Cerebellar Granule Neuron Precursors by Maintaining Proliferation

AbstractIn the developing cerebellar cortex, granule neuron precursors (GNPs) proliferate and commence differentiation in a superficial zone, the external granule layer (EGL). The molecular basis of the transition from proliferating precursors to immature differentiating neurons remains unknown. Notch signaling is an evolutionarily conserved pathway regulating the differentiation of precursor cells of many lineages. Notch2 is specifically expressed in proliferating GNPs in the EGL. Treatment of GNPs with soluble Notch ligand Jagged1, or overexpression of activated Notch2 or its downstream target HES1, maintains precursor proliferation. The addition of GNP mitogens Jagged1 or Sonic Hedgehog (Shh) upregulates the expression of HES1, suggesting a role for HES1 in maintaining precursor proliferation

What are the experiences of adults returning to work following recovery from Guillain-Barré syndrome? An interpretative phenomenological analysis

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2009 Informa UK Ltd.Purpose. Guillain-Barré syndrome (GBS) is a transient inflammatory disorder affecting peripheral nerves, characterised by weakness and numbness in limbs, upper body and face. Residual problems affect a large minority, and complicate return to work. This qualitative study explored the experiences of people who returned to work following their diagnosis of GBS and recovery, to gain insight into factors that facilitated or inhibited this process. Method. Five people participated in in-depth interviews. Individual and common experiences were explored through interpretative phenomenological analysis. Findings. Three recurring themes are presented: the perceived value of work; losing and recovering a familiar identity at work; and dilemmas around using support and adaptations at work. Certain individual issues also emerged but are beyond the scope of this article. Participants tended to measure their recovery in terms of returning to work yet continued to experience certain physical and psychosocial difficulties at work related to GBS, which required active coping strategies. Limited public awareness of GBS was perceived as a hindrance when returning to work. Conclusion. This study provides a rich account of the experiences that people encounter returning to work following GBS. Rehabilitation specialists may offer more effective preparation for this process, drawing upon the issues identified

Effects of Changing Climate and Water Availability on Four Riparian Species in the Southwestern United States

The Lower Colorado River and Rio Grande Basins are home to many riparian species of different degrees of rarity. In our study we focused on two species of birds and two species of gartersnakes that are associated with water: the Yellow-Breasted Chat (Icteria virens), the American Yellow Warbler (Setophaga petechia), the Mexican Gartersnake (Thamnophis eques) and the Narrow-headed Gartersnake (T. rufipunctatus). While the extent of distributions of these species is relatively large, they are often patchily distributed in populations that are small. To evaluate the vulnerability of these species at a landscape scale due to changes in hydrology, we built models of suitability of current and future landscapes for these species. We relied on climatic and hydrological predictions, developed by the Bureau of Reclamation (as part of the WATERSmart program) and NASA’s Moderate-Resolution Imaging Spectroradiometer (MODIS), to derive spatially-explicit metrics that quantify the greenness of riparian vegetation in time. Using WATERSmart data, we were able to project these metrics into the future. The projected changes in water availability by end of the century will directly affect the availability of permanent water and riparian vegetation that surrounds suitable habitats of our study species. Our results suggest significant changes in future landscape suitability (up to 64% of area) for all species that are in addition to other threats. Best models included riparian vegetation as an important component of the predictions but we note that finer scale examination of hydrology and climate effects on habitats would be more useful for effective management

Myosin II Motors and F-Actin Dynamics Drive the Coordinated Movement of the Centrosome and Soma during CNS Glial-Guided Neuronal Migration

SummaryLamination of cortical regions of the vertebrate brain depends on glial-guided neuronal migration. The conserved polarity protein Par6α localizes to the centrosome and coordinates forward movement of the centrosome and soma in migrating neurons. The cytoskeletal components that produce this unique form of cell polarity and their relationship to polarity signaling cascades are unknown. We show that F-actin and Myosin II motors are enriched in the neuronal leading process and that Myosin II activity is necessary for leading process actin dynamics. Inhibition of Myosin II decreased the speed of centrosome and somal movement, whereas Myosin II activation increased coordinated movement. Ectopic expression or silencing of Par6α inhibited Myosin II motors by decreasing Myosin light-chain phosphorylation. These findings suggest leading-process Myosin II may function to “pull” the centrosome and soma forward during glial-guided migration by a mechanism involving the conserved polarity protein Par6α