"Credit Cycle" in an OLG Economy with Money and Bequest

In the late '90s Kiyotaki and Moore (KM) put forward a new framework (Kiyotaki and Moore,1997) to explore the Financial Accelerator hypothesis. The original model was framed in an Infinitely Lived Agent context (ILA-KM economy). As in KM we develop a dynamic model in which the durable asset ("land") is not only an input but also collateralizable wealth to secure lenders from the risk of borrowers' default. In this paper, however, we model an OLG-KM economy whose novel feature is the role of money as a store of value and of bequest as a vehicle of resources to be "invested" in landholding. The dynamics generated by the model are complex. Not only cyclical patterns are routinely generated but the periodicity and amplitude are irregular. A route to chaotic dynamics is open.

Enhancement of cooperation in highly clustered scale-free networks

We study the effect of clustering on the organization of cooperation, by analyzing the evolutionary dynamics of the Prisoner's Dilemma on scale-free networks with a tunable value of clustering. We find that a high value of the clustering coefficient produces an overall enhancement of cooperation in the network, even for a very high temptation to defect. On the other hand, high clustering homogeneizes the process of invasion of degree classes by defectors, decreasing the chances of survival of low densities of cooperator strategists in the network.Comment: 4 pages, 3 figure

New Implant Design with Midcrestal and Apical Wing Thread for Increased Implant Stability in Single Postextraction Maxillary Implant

Background. The immediate placement of a dental implant could represent an option treatment for the rehabilitation of a postextractive missing tooth socket to replace compromised or untreatable teeth, with the advantage of single-session surgery. In this way, the anatomy of the alveolar bone defect, the preservation of the buccal cortical bone, and the primary stability of the fixture represent the critical factors that consent a precise implant placement. Objective. This case report describes a novel fixture design for postextractive alveolar socket immediate implant. Methods. Two patients (25 and 31 years old) were treated for postextractive dental implant placement to replace both central upper incisor teeth with four implants. The residual bone implant gap was not filled with graft or bone substitute. The restoration was provided following a standard loading protocol by a cement-sealed prosthetic abutment. Results. Clinically, all implants positioned showed an excellent insertion torque. No postoperative complications were reported. At 6 months of healing, the buccal cortical bone and the implant stability were present and well maintained. Conclusion. The evidence of this study allows us to underline the possible advantages of this new fixture design for postextractive implant technique

Daily Rhythms of Serum Vitamin D-Metabolites, Calcium and Phosphorus in Horses

Many physiological processes of domestic animals exhibit daily rhythmicity. The goal of the present study was to investigate the daily rhythms of calcium, inorganic phosphorus and 24,25-(OH)2-D3, 25-(OH)-D3 and 1,25-(OH)2-D3 in the blood serum of horses. Five Thoroughbred mares from the same farm, clinically healthy and placed in individual stalls, at the same environmental temperature and photoperiod were used. For 30 days prior to the study, the animals underwent the same pattern of daily activity. Blood samples were collected at 4 h-intervals for 48 consecutive h, starting at 08:00 h of the first day and finishing at 04:00 h of the second day, via intravenous cannula inserted into the jugular vein. Each individual sample was assessed for serum concentration of calcium and inorganic phosphorus by means of a UV spectrophotometric test, and serum concentration of 24, 25-(OH)-D3, 25-(OH)-D3, and 1,25-(OH)2-D3 were assessed by means of HPLC method. Data analysis was conducted by one-way repeated measures analysis of variance (ANOVA) and by the single cosinor method. ANOVA showed a significant effect of time on all the variables studied (p < 0.0001) and post-hoc test (SNK) showed significant differences (p < 0.001) comparing all the time intervals of 4 h, on either day. The application of the periodic model and the statistical analysis of the cosinor procedure allowed defining the periodic variables and their acrophases (expressed in hours) during the 2 days of monitoring. Calcium showed diurnal acrophases at 15:00 h for the 1st day and at 15:48 for the 2nd day; inorganic phosphorus showed diurnal coincident acrophases at 14:32 h both for the 1st and 2nd day and 25-(OH)-D3 showed diurnal acrophases at 14:08 h for the 1st day and at 15:04 h for the 2nd day. The results obtained could be useful for standardizing blood sampling according to the time of day and for optimizing the administration of these substances according to their circadian or other rhythms

Seasonal variations of the serum proteins in sheep and goats (Short Communication)

Abstract. The aim of this study was to assess the seasonal trend of the serum protein content of sheep and goats. The tested animals were six female goats (Maltese breed) and six female sheep (Valle del Belice breed). All animals were clinically healthy and not pregnant or lactating before or during the study. On blood samples, collected through an external jugular venipuncture every 30 days for 12 months, electrophoresis was performed using a semiautomated AGE system and then electrophoretic curves with the relative protein concentrations were analyzed. One way for repeated measure analysis of variance (ANOVA) was applied to determine the effect of time and by means of cosinor rythmometry, mesor (mean level), amplitude (half the range of oscillation) and acrophase (Φ, time of peak) were determined. The results showed a seasonal rhythm on Albumin and Alumin/Globulin ratio for sheep and goats, with different acrophases, winter for goats and spring for sheep. A seasonal rhythm was shown also in Alpha 2 globulins by sheep and in Beta globulins by goats. The difference in the acrophase can be attributed to a different production pattern of melatonin in goat, so the liver production of albumin is major during the winter that has a longer scotophase

Cell Shortening and Calcium Homeostasis Analysis in Adult Cardiomyocytes via a New Software Tool

Intracellular calcium (Ca2+) is the central regulator of heart contractility. Indeed, it couples the electrical signal, which pervades the myocardium, with cardiomyocytes contraction. Moreover, alterations in calcium management are the main factors contributing to the mechanical and electrical dysfunction observed in failing hearts. So, simultaneous analysis of the contractile function and intracellular Ca2+ is indispensable to evaluate cardiomyocytes activity. Intracellular Ca2+ variations and fraction shortening are commonly studied with fluorescent Ca2+ indicator dyes associated with microscopy techniques. However, tracking and dealing with multiple files manually is time-consuming and error-prone and often requires expensive apparatus and software. Here, we announce a new, user-friendly image processing and analysis tool, based on ImageJ-Fiji/MATLAB® software, to evaluate the major cardiomyocyte functional parameters. We succeeded in analyzing fractional cell shortening, Ca2+ transient amplitude, and the kinematics/dynamics parameters of mouse isolated adult cardiomyocytes. The proposed method can be applied to evaluate changes in the Ca2+ cycle and contractile behavior in genetically or pharmacologically induced disease models, in drug screening and other common applications to assess mammalian cardiomyocyte functions

Editorial: Advances in brain imaging and stimulation methods for cognitive function investigation

The Research Topic “Advances in brain imaging and stimulation methods for cognitive function investigation” gathers basic research and clinical results of experimental brain imaging and stimulation techniques which are used to investigate mechanisms of cognitive function and dysfunction