Links and Hyperlinks: An Empirical Analysis of Internet Portal Alliances, 1995-1999

This paper examines the structure of over 100 alliances by Internet portals from 1995 to 1999. These alliances were an attractive empirical testing ground because of the large number and heterogeneous nature of the contracts, the high standards for disclosure in the industry, and the careful delineation of ownership, control, exclusivity, and other provisions in the contracts. The division of ownership and allocation of control rights displayed patterns consistent with the predictions in the incomplete contracting literature. Similarly, the exclusivity of the agreements appeared to vary, at least weakly, with the value of the product or service being made available to the portal, consistent with the licensing literature. In other cases, particularly in regard to the differing allocation of ownership and control and the varying completeness of the contracts, the empirical patterns indicated a more complex world than the one that theory led us to anticipate.

Anemia is associated with increased risk of non-vertebral osteoporotic fractures in elderly men : the MrOS Sweden cohort

Summary: This study includes 1005 men from the Gothenburg part of the Osteoporotic Fracture in Men Study (MrOS). Included are 66 men with anemia (hemoglobin < 130 g/L). The follow-up time was up to 16 years, and the main results are that anemia is associated with all fractures and non-vertebral osteoporotic fractures. Introduction: Anemia and osteoporotic fractures are conditions that are associated with increased morbidity and mortality. Clinical studies have suggested that anemia can be used as a predictor of future osteoporotic fractures. Method: Men from the Osteoporotic Fractures in Men Study (MrOS) Sweden, Gothenburg, with available hemoglobin (Hb) values (n = 1005, median age 75.3 years (SD 3.2)), were included in the current analyses. Of these, 66 suffered from anemia, defined as Hb < 130 g/L. Median follow-up time for fracture was 10.1 years and the longest follow-up time was 16.1 years. Results: Men with anemia had, at baseline, experienced more falls and had a higher prevalence of diabetes, cancer, prostate cancer, hypertension, and stroke. Anemia was not statistically significantly associated with bone mineral density (BMD). Men with anemia had higher serum levels of fibroblast growth factor 23 (iFGF23) (p < 0.001) and phosphate (p = 0.001) and lower serum levels of testosterone (p < 0.001) and estradiol (p < 0.001). Moreover, men with anemia had an increased risk of any fracture (hazard ratio (HR) 1.97, 95% CI 1.28–3.02) and non-vertebral osteoporotic fracture (HR 2.15, 95% CI 1.18–3.93), after adjustment for age and total hip BMD, in 10 years. The risk for any fracture was increased in 10 and 16 years independently of falls, comorbidities, inflammation, and sex hormones. The age-adjusted risk of hip fracture was increased in men with anemia (HR 2.32, 95% CI 1.06–5.12), in 10 years, although this was no longer statistically significant after further adjustment for total hip BMD. Conclusions: Anemia is associated with an increased risk for any fracture and non-vertebral osteoporotic fracture in elderly men with a long follow-up time. The cause is probably multifactorial and our results support that anemia can be used as a predictor for future fracture

Methodological Note: On Using Personal Digital Assistants (PDAs) for Survey Administration in the Study of Youth Development

Applied developmental scientists face the challenge of identifying research methods that enable the efficient collection of data from youth of diverse social backgrounds (e.g., ethnic. racial, religious, economic) and varying levels cognitive-linguistic and attentional skills. In addition, because access to youth during school time is often limited by educators’ desire to preserve instructional time, finding methodologies to collect data from youth that are highly efficient, and also those that are feasible in less structured settings, are needed. This article outlines some of the benefits and limitations of using a voice-enhanced survey delivered on a personal digital assistants (PDA) as a method of gathering data from diverse youth in both, in and out-of-school contexts

We’re Here, We’re Hopeful, and We Can Do Well: Conceptions and Attributes of Positive Youth Development among Immigrant Youth

Using qualitative and quantitative information from Grades 8 and 9 of the 4-H Study of Positive Youth Development (PYD), we describe the conceptions of thriving youth present within adolescent immigrants to the United States, and interrelate these conceptions with quantitative scores for PYD, contribution, and positive future orientation. Conceptions of thriving that included positive future orientation were associated with higher quantitative scores for PYD and Contribution. Conceiving of thriving as making contributions to themselves or their communities was associated with higher quantitative scores for Contribution. These findings suggest that immigrant youth whose qualitative definitions of thriving include the U.S.-based conceptions of PYD show quantitative evidence of positive functioning. We discuss limitations of the present study and directions for future research

Targeting autophagy by small molecule inhibitors of vacuolar protein sorting 34 (Vps34) improves the sensitivity of breast cancer cells to Sunitinib

Resistance to chemotherapy is a challenging problem for treatment of cancer patients and autophagy has been shown to mediate development of resistance. In this study we systematically screened a library of 306 known anti-cancer drugs for their ability to induce autophagy using a cell-based assay. 114 of the drugs were classified as autophagy inducers; for 16 drugs, the cytotoxicity was potentiated by siRNA-mediated knock-down of Atg7 and Vps34. These drugs were further evaluated in breast cancer cell lines for autophagy induction, and two tyrosine kinase inhibitors, Sunitinib and Erlotinib, were selected for further studies. For the pharmacological inhibition of autophagy, we have characterized here a novel highly potent selective inhibitor of Vps34, SB02024. SB02024 blocked autophagy in vitro and reduced xenograft growth of two breast cancer cell lines, MDA-MB-231 and MCF-7, in vivo. Vps34 inhibitor significantly potentiated cytotoxicity of Sunitinib and Erlotinib in MCF-7 and MDA-MB-231 in vitro in monolayer cultures and when grown as multicellular spheroids. Our data suggests that inhibition of autophagy significantly improves sensitivity to Sunitinib and Erlotinib and that Vps34 is a promising therapeutic target for combination strategies in breast cancer.Peer reviewe

Cell-to-cell variability in the yeast pheromone response: high throughput screen identifies genes with different effects on transmitted signal and response

Populations of isogenic cells often respond coherently to signals despite differences in protein abundance and cell state. Our previous work in the Saccharomyces cerevisiae pheromone response system (PRS) uncovered processes that reduced cell-to-cell variation in signal and response. To understand these and other processes that controlled variation, we generated a whole-genome collection of haploid strains with deletions in non-essential genes and used high-throughput flow cytometry to screen more than 1000. We identified 50 'variation genes' required for normal cell-to-cell variability in signal and response. Some genes affected only signal variability, signal strength, or system output, defining these quantities as separable 'axes' of system behavior. Two genes affected cytoplasmic microtubule function