Double affine Lie algebras and finite groups

We introduce and begin to study Lie theoretical analogs of symplectic reflection algebras for a finite cyclic group, which we call "cyclic double affine Lie algebra". We focus on type A : in the finite (resp. affine, double affine) case, we prove that these structures are finite (resp. affine, toroidal) type Lie algebras, but the gradings differ. The case which is essentially new involves $\mathbb{C}[u,v]$. We describe its universal central extensions and start the study of its representation theory, in particular of its highest weight integrable modules and Weyl modules. We also consider the first Weyl algebra $A_1$ instead of the polynomial ring $\mathbb{C}[u,v]$, and, more generally, a rank one rational Cherednik algebra. We study quasi-finite highest weight representations of these Lie algebras.Comment: 31 page

Executive equity compensation and incentives: a survey

Stock and option compensation and the level of managerial equity incentives are aspects of corporate governance that are especially controversial to shareholders, institutional activists, and government regulators. Similar to much of the corporate finance and corporate governance literature, research on stock-based compensation and incentives has not only generated useful insights, but also produced many contradictory findings. Not surprisingly, many fundamental questions remain unanswered. In this study, the authors synthesize the broad literature on equity-based compensation and executive incentives and highlight topics that seem especially appropriate for future research.Executives ; Stockholders ; Corporate governance

Mental health treatment seeking by military members with posttraumatic stress disorder : findings on rates, characteristics, and predictors from a nationally representative Canadian military sample

Objective: The goal of this study was to identify rates, characteristies, and predictors of mental health treatment seeking by military members with posttraumatic stress disorder (PTSD). Method: Our sample was drawn from the 2002 Canadian Community Health Survey-Canadian Forces Supplement (CCHS-CF) dataset. The CCHS-CF is the first epidemiologic survey of PTSD and other mental health conditions in the Canadian military and includes 8441 nationally representative Canadian Forces (CF) members. Of those, 549 who met the criteria for lifetime PTSD were included in our analyses. To identify treatment rates and characteristics, we examined frequency of treatment contact by professional and facility type. To identify predictors of treatment seeking, we conducted a binary logistic regression with lifetime treatment seeking as the outcome variable. Results: About two-thirds of those with PTSD consulted with a professional regarding mental health problems. The most frequently consulted professionals, during both the last year and lifetime, included social workers and counsellors, medical doctors and general practitioners, and psychiatrists. Consultations during the last year most often took place in a CF facility. Treatment seeking was predicted by cumulative lifetime trauma exposure, index traumatic event type, PTSD symptom interference, and comorbid major depressive disorder. Those with comorbid depression were 3.75 times more likely to have sought treatment than those without. Conclusions: Although a significant portion of military members with PTSD sought mental health treatment, 1 in 3 never did. Trauma-related and illness and (or) need factors predicted treatment seeking. Of all the predictors of treatment seeking, comorbid depression most increased the likelihood of seeking treatment

Evaluating the role of p38 MAPK in the accelerated cell senescence of Werner syndrome fibroblasts

Progeroid syndromes show features of accelerated ageing and are used as models for human ageing, of which Werner syndrome (WS) is one of the most widely studied. WS fibroblasts show accelerated senescence that may result from p38 MAP kinase activation since it is prevented by the p38 inhibitor SB203580. Thus, small molecule inhibition of p38-signalling may be a therapeutic strategy for WS. To develop this approach issues such as the in vivo toxicity and kinase selectivity of existing p38 inhibitors need to be addressed, so as to strengthen the evidence that p38 itself plays a critical role in mediating the effect of SB203580, and to find an inhibitor suitable for in vivo use. In this work we used a panel of different p38 inhibitors selected for: (1) having been used successfully in vivo in either animal models or human clinical trials; (2) different modes of binding to p38; and (3) different off-target kinase specificity profiles, in order to critically address the role of p38 in the premature senescence seen in WS cells. Our findings confirmed the involvement of p38 in accelerated cell senescence and identified p38 inhibitors suitable for in vivo use in WS, with BIRB 796 the most effective

Use of inert gas jets to measure the forces required for mechanical gene transfection

BACKGROUND: Transferring genes and drugs into cells is central to how we now study, identify and treat diseases. Several non-viral gene therapy methods that rely on the mechanical disruption of the plasma membrane have been proposed, but the success of these methods has been limited due to a lack of understanding of the mechanical parameters that lead to cell membrane permeability. METHODS: We use a simple jet of inert gas to induce local transfection of plasmid DNA both in vitro (HeLa cells) and in vivo (chicken chorioallantoic membrane). Five different capillary tube inner diameters and three different gases were used to treat the cells to understand the dependency of transfection efficiency on the dynamic parameters. RESULTS: The simple setup has the advantage of allowing us to calculate the forces acting on cells during transfection. We found permeabilization efficiency was related to the dynamic pressure of the jet. The range of dynamic pressures that led to transfection in HeLa cells was small (200 ± 20 Pa) above which cell stripping occurred. We determined that the temporary pores allow the passage of dextran up to 40 kDa and reclose in less than 5 seconds after treatment. The optimized parameters were also successfully tested in vivo using the chorioallantoic membrane of the chick embryo. CONCLUSIONS: The results show that the number of cells transfected with the plasmid scales with the dynamic pressure of the jet. Our results show that mechanical methods have a very small window in which cells are permeabilized without injury (200 to 290 Pa). This simple apparatus helps define the forces needed for physical cell transfection methods

Safety and Pharmacokinetics of Multiple Doses of Intravenous Ofloxacin in Healthy Volunteers

The safety and pharmacokinetics of ofloxacin in 48 healthy male volunteers were studied in a two-center, randomized, double-blind, placebo-controlled study. Ofloxacin (200 or 400 mg) or placebo was administered as 1-h infusions every 12 h for 7 days. Plasma ofloxacin concentrations were measured by high-performance liquid chromatography. Mean harmonic half-lives ranged from 4.28 to 4.98 h in the 200-mg dosing group and from 5.06 to 6.67 h in the 400-mg dosing group. Intragroup comparisons of trough plasma concentration-versus-time data from study days 2 through 7 revealed that steady state was achieved by day 2 of both multiple-dose regimens. Intergroup comparisons of mean harmonic half-lives, the areas under the concentration-time curve from 0 to 12 and 0 to 60 h, clearance, and apparent volume of distribution (area method) revealed that the pharmacokinetics of ofloxacin are dose independent. Both ofloxacin dosage regimens appeared to be reasonably well tolerated. The two dosage regimens of ofloxacin, 200 or 400 mg every 12 h, appear to be safe and provide serum drug concentrations in excess of the MICs for most susceptible pathogens over the entire dosing interval

Oral Health Quality Improvement in the Era of Accountability

The purpose of this report is to review the current status and trends in quality measurement and improvement and describe efforts underway to expand and enhance those efforts. The report will also describe opportunities to use emerging oral health measurement and quality improvement systems to improve and maintain the oral health of the U.S. population

Academic self-concept, autonomous academic motivation, and academic achievement : mediating and additive effects

Three conceptual models were tested to examine the relationships among academic self-concept, autonomous academic motivation, and academic achievement. This allowed us to determine whether 1) autonomous academic motivation mediates the relation between academic self-concept and achievement, 2) academic self-concept mediates the relation between autonomous academic motivation and achievement, or 3) both motivational constructs have an additive effect on academic achievement. A total of 925 high school students (404 boys and 521 girls) were asked to complete a questionnaire on two occasions separated by a year interval. Results from SEM analyses provided good support for the hypothesized model positing that autonomous academic motivation mediates the academic self-concept–academic achievement relation. Results are discussed in light of self-determination theory and self-concept theory