Systems of the Kowalevski type and discriminantly separable polynomials

Starting from the notion of discriminantly separable polynomials of degree two in each of three variables, we construct a class of integrable dynamical systems. These systems can be integrated explicitly in genus two theta-functions in a procedure which is similar to the classical one for the Kowalevski top. The discriminnatly separable polynomials play the role of the Kowalevski fundamental equation. The natural examples include the Sokolov systems and the Jurdjevic elasticae.Comment: 29 pages, 0 figures. arXiv admin note: substantial text overlap with arXiv:1106.577

Technical change and the postwar slowdown in Soviet economic growth

The existing studies usually find that technical change was very important in constraining the economic growth of the Soviet Union. While these studies have been successful in quantifying the extent of technical change, they have been less successful in quantifying its nature. This paper probes the essence of technical change by analysing its direction and bias. I find that the Soviet Union achieved strong increases in labour efficiency until the 1960s. Although the labour efficiency growth subsequently slowed down, it is capital efficiency that drove the postwar slowdown in economic growth. I argue that labour shortages, combined with an inadequate investment policy, retarded the Soviet capital efficiency

Religious change and persistence in Bosnia: Poverty, conversions, and nationalism, 1468-2013

While economic historians have invested a great deal of effort into understanding the economic consequences of religion, they have invested comparatively little effort into understanding the determinants of religious affiliation. This paper analyses conversions to Islam in the OttomanBosnia. Employing village-level data constructed from the Ottoman tax registers of 1468 and 1604, we find that households in the initially poorer villages were more likely to convert to Islam. This finding is consistent with the notion that the poll tax that non-Muslims had to pay stimulated the poorer Christians to convert to Islam. Using a stream of modern population censuses since the 19th century, we also find that our results hold after the end of the Ottoman rule and its discriminatory tax in 1878. We hypothesize that religious identity persisted because it became embedded into the rising national consciousness during the nineteenth century, reinforcing the cost of changing religion

Effects of a comprehensive bariatric program implementation on 30-day readmission and 30-day ER/infusion clinic visit rates due to dehydration

Background: Program accreditation requires adherence to MBSAQIP standards to assist patient in making needed changes to his/her diet and lifestyle. However, literature provides conflicting information regarding the value of a comprehensive bariatric program accreditation and its effects on 30-day readmission and 30-day ER/infusion clinic visit due to dehydration development. Objectives: To examine the effects of implementing a comprehensive bariatric surgical program on 30-day readmission rates, and 30-day emergency room (ER) and infusion clinic visit rates due to dehydration for bariatric surgical patients. Methods: Our study was a retrospective separate sample pre-post intervention chart review. The data were collected before and after implementing a comprehensive bariatric program using a convenience sample of 180 adult patients (age ≥18) that had bariatric surgery at an acute care hospital. We conducted Chi-square analyses with significance levels set at 0.05. Results: Among the 180 patients, majority had laparoscopic gastric bypass (n=112, 62.2%). Among the 180 patients, 55 (31%) were in the pre-intervention and 125 (69%) were in the postintervention group. A total of 7 (3.9%) had 30-day readmission. Significantly more patients (n=5, 9.1%) in the pre-intervention group had 30-day readmission compared to those in the postintervention group (n=2, 1.6%; X2=5.73, p=0.03). Among the 180 patients, 8 (4.4%) had 30-day ER/infusion clinic visit due to dehydration. No difference was found in 30-day ER/infusion clinic visit between the pre-intervention (n=5, 9.1%) and the post-intervention groups (n=3, 2.4%; X2=4.03, p=0.06). Conclusion: Implementation of comprehensive bariatric program was effective in lowering 30- day readmission rate

The last Yugoslavs: ethnic diversity, national identity and civil war

Nation-building is often proposed as a device for integration and conflict reduction in ethnically divided societies. This paper analyses the role of interethnic contact in the process of nation formation within the unique historical setting of the multi-ethnic Yugoslavia. Using historical border changes as a proxy for exogenous population movements that influenced ethnic diversity, I find that interethnic contact stimulated the formation of the Yugoslav national identity. In addition, aligned with the notion that nation formation can reduce the incidence of ethnic conflict, I find that areas with more self-declared Yugoslavs experienced a lower intensity of conflict during the Bosnian War of 1992-1995

Unclogging the zinc sink: examining the role of zinc trafficking in mucolipidosis type IV and lysosomes

Zinc is an essential micronutrient that regulates many cellular processes. Deficits or excessive abundance in zinc concentration have catastrophic consequences for organisms and have been linked to many human diseases. Consequently, intracellular zinc levels are kept within narrow limits by an orchestrated network of zinc binding proteins and transporters. Within the cell, zinc accumulates in virtually all organelles, including lysosomes, which break down cellular waste materials. Lysosomes have recently become the focus of zinc regulation, as they have been shown to absorb zinc from the cytoplasm and contribute to zinc-induced toxicity. Additionally, recent evidence of zinc permeability of the lysosomal ion channel TRPML1, and the evidence of abnormal zinc levels in cells deficient in TRPML1, suggested a role for TRPML1 in zinc transport. Mutations in TRPML1 in humans result in a neurodegenerative lysosomal storage disorder called Mucolipidosis type IV (MLIV) characterized by psychomotor and mental retardation. I have found that an siRNA-driven TRPML1 knockdown in HeLa cells leads to the buildup of enlarged cytoplasmic and lysosomal vesicles filled with zinc via live cell confocal imaging. Also, lysosomal enlargement and zinc buildup in TRPML1-deficient cells exposed to zinc are ameliorated by knocking down the lysosomal zinc importer ZnT4. This data provides important insights into the function of TRPML1 and the role of zinc in MLIV and other neurodegenerative diseases. Moreover, I have found that lysosomes, generally, play a cytoprotective role during exposure to extracellular zinc, which requires lysosomal acidification and exocytosis. Specifically, inhibition of lysosomal function with bafilomycin redistributed zinc pools to other organelles and increased cell death. Furthermore, inhibition of lysosomal exocytosis through knockdown of lysosomal SNARE proteins VAMP7 and SYT7 suppressed zinc secretion. VAMP7 knockdown increased apoptosis. Interestingly however, the overexpression of the lysosomal biogenesis transcription factor TFEB increased zinc secretion, suggesting that zinc secretion correlates with lysosomal function. Overall, these data underscore a role for TRPML1 and lysosomes in zinc metabolism and suggest that lysosomes form a “zinc sink” to dynamically buffer and counteract high zinc levels. This is a novel paradigm that implicates lysosomes in an entirely new function and identifies a completely new zinc detoxification pathway