Intertemporal Market Divison

In dynamic entry-and-exit models, common understanding is that potential entrants will enter into the market up to the point where all excess profits are eroded. Dominant incumbent positions are possible only under specific circumstances, such as the presence of substantial barriers to entry, or when incumbents can credibly threaten to punish rivals with losses upon entry. In this paper, we report on an equilibrium with market dominance that exists in a simple two-firm model that features neither entry barriers nor punishment strategies. this equilibrium induces an alternating monopoly - despite the fact that the model also sustains a Cournot duopoly. Even when initially both firms are active in the market, an alternating monopoly reveals itself rather quickly. Moreover, the alternating monopoly equilibrium Pareto dominates the Cournot equilibrium - as it is close to the cartel outcom.microeconomics ;

Jerónimo Pardo on the unity of mental propositions

Originally motivated by a sophism, Pardo's discussion about the unity of mental propositions allows him to elaborate on his ideas about the nature of propositions. His option for a non-composite character of mental propositions is grounded in an original view about syncategorems: propositions have a syncategorematic signification, which allows them to signify aliquid aliqualiter, just by virtue of the mental copula, without the need of any added categorematic element. Pardo's general claim about the simplicity of mental propositions is developed into several specific thesis about mental propositions: a) it is not judgement which gives its unity to mental propositions, but judicative acts always follow some previous apprehensive act that is simple in its own right; b) this simplicity is compatible with a certain kind of complexity, that can be explained in terms of the "causal history" of the acts of knowing; c) traditional conceptions about subject and predicate must be recast, while keeping their usual explicative power concerning logical properties; d) of course, the traditional conception about the copula has been modified, giving rise to a fully innovative conception of the nature of mental propositions. Nevertheless, this innovative conception of mental language seems still infected by certain "common sense" prejudices, which lead Pardo to propose also a provocative conception of vocal language, which I consider unnecessary

Surgical Implications of Coronary Arterial Anatomy in Adults with Congenital Cardiac Disease

In adults with congenital heart disease coronary arterial anatomy, normal as well as anomalous, may have implications in surgical reconstruction of an underlying cardiac structure

Purpose in life in patients with rheumatoid arthritis

To evaluate the role of purpose in life among people with rheumatoid arthritis (RA), a questionnaire comprising the Purpose in Life test (PIL) and the purpose in life dimension of the Psychological Well-Being test (PWB-pil) was sent to a random sample of 300 patients with RA. Additional questions comprised sociodemographic and disease characteristics, physical, mental and social functioning, coping (Coping with rheumatic stressors questionnaire), and quality of life (RAND-36). Associations between sociodemographic and disease characteristics, physical, mental and social functioning, and coping on the one side and the two measures of purpose in life on the other side and associations between the two purpose of life measures and physical and mental dimensions of quality of life were assessed by means of univariate and multivariate regression analyses. The response rate was 156 of 300 (52%). The median PIL and PWB-pil scores were 103 (range 63–131) and 82 (41–110), respectively. A lower age, a better mental health status, and an optimistic coping style were significantly associated with both higher PIL and PWB-pil scores, whereas more participation in leisure and/or social activities was associated with a higher PIL score. It was found that the PIL and PWB-pil contributed independently and significantly to the mental component summary scale of the RAND-36. In RA patients, lower age, a better mental health status, an optimistic coping style, and participation in leisure and/or social activities were significantly associated with more sense of purpose in life. Purpose in life pays a significant and independent contribution to the mental component of quality of life. These findings highlight the significance of the concept of purpose in life in patients with RA

Evidence for position effects as a variant ETV6-mediated leukemogenic mechanism in myeloid leukemias with a t(4;12)(q11-q12;p13) or t(5;12)(q31;p13)

The ETV6 gene (first identified as TEL) is a frequent target of chromosomal translocations in both myeloid and lymphoid leukemias. At present, more than 40 distinct translocations have been cytogenetically described, of which 13 have now also been characterized at the molecular level. These studies revealed the generation of in-frame fusion genes between different domains of ETV6 and partner genes encoding either kinases or transcription factors. However, in a number of cases-including a t(6;12)(q23;p13), the recurrent t(5;12)(q31;p13), and some cases of the t(4;12)(q11-q12;p13) described in this work-functionally significant fusions could not be identified, raising the question as to what leukemogenic mechanism is implicated in these cases. To investigate this, we have evaluated the genomic regions at 4q11-q12 and 5q31, telomeric to the breakpoints of the t(4;12)(q11-q12;p13) and t(5;12)(q31;p13). The homeobox gene GSH2 at 4q11-q12 and the IL-3/CSF2 locus at 5q31 were found to be located close to the respective breakpoints. In addition, GSH2 and IL-3 were found to be ectopically expressed in the leukemic cells, suggesting that expression of GSH2 and IL-3 was deregulated by the translocation. Our results indicate that, besides the generation of fusion transcripts, deregulation of the expression of oncogenes could be a variant leukemogenic mechanism for translocations involving the 5' end of ETV6, especially for those translocations lacking functionally significant fusion transcripts

Cortisol response to critical illness:Effect of intensive insulin therapy

Context: Both excessive and insufficient activation of the hypothalamic-pituitary-adrenal axis in response to critical illness is associated with increased mortality. Objective: The objective of the study was to study the effect of intensive insulin therapy, recently shown to reduce mortality and morbidity of critically ill patients, on the cortisol response to critical illness. Design: This was a preplanned subanalysis of a large randomized, controlled study measuring serum total cortisol, cortisol-binding globulin, and albumin and calculating free cortisol levels. Setting: The study was conducted at a university hospital surgical intensive care unit. Patients: Four hundred fifty-one critically ill patients dependent on intensive care for more than 5 d and 45 control subjects matched for gender, age, height, and weight participated in this study. Intervention: The intervention was strict blood glucose control to normoglycemia with insulin. Results: Total and calculated free cortisol levels were equally elevated upon admission in both patient groups and thereafter were lower in intensive insulin-treated patients. Lower cortisol levels statistically related to the outcome benefit of intensive insulin therapy. Cortisol-binding globulin levels and structure were affected by critical illness but not insulin therapy, and neither were albumin levels. Administration of hydrocortisone in so-called replacement dose resulted in severalfold higher total and free cortisol levels, indicating that reevaluation of the doses used is warranted. Conclusions: Lower serum cortisol levels in critically ill patients receiving intensive insulin therapy statistically related to improved outcome with this intervention. The lower cortisol levels were not related to altered cortisol-binding capacity.</p

Morbidity related to defunctioning ileostomy closure after ileal pouch-anal anastomosis and low colonic anastomosis

Purpose Defunctioning ileostomies are widely performed in order to prevent or treat anastomotic leakage after colorectal surgery. The aim of the present study was to determine morbidity related to stoma closure and to identify predictive factors of a complicated postoperative course. Methods A consecutive series of 138 patients were retrospectively analyzed after stoma reversal. Data collection included general demographics and surgery-related aspects. Morbidity related to stoma closure was retrieved from our prospectively collected registry of complications. Results In 74 of 138 patients, defunctioning ileostomy was performed after restorative proctocolectomy and ileal pouchanal anastomosis (IPAA). The remaining ileostomies (n=64) were constructed after a low colorectal or coloanal anastomosis. A total of 46 complications were recorded in 28 patients resulting in an overall complication rate of 20.3%. Anastomotic leakage rate was 4.3%, and reoperation rate was 8.0%. The number of complications according to the Clavien-Dindo classification was 5 for grade I (10.9%), 26 for grade II (56.5%), 13 for grade III (28.3%), 1 for grade IV (2.2%), and 1 for grade V (2.2%). Multivariate analysis revealed a significantly higher ASA score in the complicated group (P=0.015, odds ratio 2.6, 95% confidence interval 1.2-5.6). Conclusions Closure of a defunctioning ileostomy is associated with 20% morbidity and a reoperation rate of 8%. There is an urgent need for criteria on which a more selective use of a defunctioning ileostomy after low colonic anastomosis or IPAA can be based given its associated morbidit

Is methotrexate safe for men with an immune-mediated inflammatory disease and an active desire to become a father? Results of a prospective cohort study (iFAME-MTX)

Introduction Current scientific evidence guiding the decision whether men with an active desire to become a father should be treated with methotrexate (MTX) remains controversial. We aimed to prospectively evaluate the testicular toxicity profile of MTX focusing on several markers of male fertility, including semen parameters and sperm DNA fragmentation index (sDFI). As a secondary outcome, we aimed to evaluate whether MTX-polyglutamates can be detected in spermatozoa and seminal plasma and to evaluate the enzymatic activity in spermatozoa of folylpolyglutamate synthetase (FPGS). Methods In a prospective cohort study, men ≥18 years who started therapy with MTX were invited to participate (MTX-starters). Participants were instructed to produce two semen samples (a pre-exposure and a post-exposure sample after 13 weeks). Healthy men ≥18 years were invited to participate as controls. Conventional semen analyses, male reproductive endocrine axis and sDFI were compared between groups. FPGS enzymatic activity and MTX-PG1-5 concentrations were determined by mass spectrometry analytical methods. Results In total, 20 MTX-starters and 25 controls were included. The pre-exposure and postexposure semen parameters of MTX-starters were not statistically significant different. Compared with healthy controls, the conventional semen parameters and the sDFI of MTX-starters were not statistically significant different. These data were corroborated by the marginal accumulation of MTX-PGs in spermatozoa, consistent with the very low FPGS enzymatic activity associated with the expression of an alternative FPGS splice-variant. Discussion Treatment with MTX is not associated with testicular toxicity, consistent with the very low concentration of intracellular MTX-PG. Therefore, therapy with MTX can be safely started or continued in men and with a wish to become a father.</p