The Foundation Payout Puzzle

This paper examines public policy toward American philanthropic foundations. We find that the major regulation bearing on foundations -- a mandated minimum endowment payout rate -- has had the effect of repressing foundation giving. Interviews with foundation trustees and presidents point to a number of significant obstacles to proper conceptualization of the payout decision in foundations. In the face of these obstacles, our survey of foundation payout behavior over 25 years reveals that most foundations simply pay out the mandated minimum amount each year, regardless of other relevant considerations. We argue that the minimum rate has gone from being a floor when it was enacted decades ago to a ceiling today. The paper concludes with an exploration of how the payout policy could usefully be reformed.This publication is Hauser Center Working Paper No. 9. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers

Manipulation of space and time in the tactile universe

The study of tactile illusions like visual illusions can reveal the brain's processing strategies. A famous tactile illusion is the cutaneous rabbit illusion. Fundamental to this illusion is the perceptual length contraction phenomenon: two taps that occur in rapid succession on the forearm are perceived as occurring closer together than they were physically placed. Our lab previously proposed a Bayesian probabilistic model that views perception as a compromise between expectation (prior experience) and sensation (likelihood of sensorineural data given hypothesized tap locations). The model proposes a low-speed prior, an expectation based on experience that objects tend to be stationary or to move slowly on the skin. When the sensation of space is unclear (e.g., taps are weak), the model predicts that expectation will strongly influence perception. Consistent with this prediction, our lab previously showed that the use of weaker taps causes more pronounced perceptual length contraction. Here we report psychophysical tests on 64 participants, which confirmed this finding. Our study also used stimulus sequences consisting of a weak and a strong tap, for which the Bayesian model predicts an asymmetric perceptual length contraction, such that the weaker tap location will be perceived to shift more than the stronger tap. The experimental results confirmed this prediction, providing further support for our Bayesian probabilistic model as an explanation for perceptual length contraction. However, our results revealed a discrepancy in the data at the smaller SOAs, which showed less length contraction than predicted. We hypothesized that participants might overestimate the smaller SOAs, an effect our lab defines as time dilation. Accordingly, in a second study we investigated the effects of varying SOA and lengths on perceived SOA. The model predicts more pronounced time dilation at smaller SOAs and larger lengths. The psychophysical data from 37 participants confirmed the trends predicted by the model.ThesisMaster of Science (MSc

Filling the infrastructure investment gap: an overview of MDBs and the Inter-American Development Bank approach

This paper provides reflections and considerations as to how MDBs including the IDB can use the Project Preparation Facilities (PPFs) to help countries fill the infrastructure gap by improving the quality of projects, reducing and mitigating risks, and leveraging private financing. Similar Studies have been conducted for PPFs in Asia , Africa and Europe. However, there is no similar assessment for LAC . This paper is the first step towards utilising the resources offered by PPFs for infrastructure development projects in LAC, and applying these useful tools to another critical region

A Nonlinear Mathematical Model of Competition and Mutualism for Examining Pollinator Intervention in Crop-Weed Interactions

Crop and weed plants often compete for water, sunlight, soil moisture, nutrients, etc. However, both of them are capable of offering floral resources to pollinators. Hence, crops, weeds, and pollinators are crucial agro-ecosystem components. Considering this aspect, a nonlinear differential equation model is developed to portray the complex interactions among the variables, viz. crop, weed, and pollinator. The proposed model is mutualism-competitive type, which comprises the mutualism of pollinators with crops and weeds and inter-specific competition between crops and weeds. The purpose of the model is to clarify how interactive dynamics affect the individual populations as time progresses. Therefore, the developed model is examined for qualitative features, including different states of equilibrium, their existences and stabilities, to get an idea of the system’s behaviour in the long run and possible bifurcations that could occur in the system’s dynamics with variation in model parameters. These perceptive qualitative findings are corroborated by numerical simulations demonstrating various dynamical patterns that could appear in the system. Results from the model indicate that coexisting weeds, crops, and pollinators can result in a stable state. Nevertheless, in some circumstances, the system may also exhibit periodic oscillations due to Hopf-bifurcation whenever there is an imbalance in the mutualism between pollinators and crops or the competition between crops and weeds

Study on the Crystal Structure and Microstructure Evolution of Shock-processed Titanium Powder

Titanium powder was rapidly solidified by using shock-wave consolidation technique. The critical parameters were controlled by intrumented detonics and pin-oscillography. The compacted specimens were investigated for crystal structure and microstructural strengthening by using standard diagnostic techniques. The density of the final product was found to be greater than 96% of the theoretical value. X-ray diffraction pattern reveals intact crystalline structure without the presence of any undesired phases. The particle size reduction indicated by XRD was supported by laser diffraction based particle size analyzer. Results from energy dispersive spectroscopy ruled out the possibility of any segregation within the compacts. Scanning electron microscopy showed crack-free, voids-free, melt-free, fracture-less compacts of titanium with a unidirectional dendrite orientation without any grain-growth

Effect of Storage Conditions on Quality and Shelf Life of Pumpkin Cookies

The chemical, physical evaluation and storage stability of cookies was carried out. studies on quality was based on physico-chemical analysis that is weight, diameter, thickness ,spread ratio, moisture, fat, protein, ash, crude fiber, carbohydrate content as well as sensory characteristics which was determined for fresh and stored sample. The characteristics of cookies were influenced by packaging material, environmental conditions and constituents present in flour. Cookies was packed in LDPE bags and stored at room temperature. This study was conducted at the interval of 15 days up to 45days

Numerical analysis of film boiling around horizontal cylindrical surfaces

Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.Stability of vapor film over a horizontal heater drags attention due to its wide spread applications in nuclear reactors, metal processing, manufacturing and chemical refineries. Existence of vapor film around the heater can cause advantages as well as disadvantages for various applications in industry and daily life. Hence understanding the film formation and its subsequent release in the form of bubble are dealt carefully by researchers in heat transfer community. Critical vapor thickness and average heat flux are the essential parameters which govern the release of vapor mass in the form of isolated bubbles from the surface. Experimental evidences have been reported in order to find out film dynamics for some specific fluids. However understanding it from the fundamental physics is still due and becomes a major challenge for heat transfer community. In this paper, numerical analysis of the film boiling heat transfer on a horizontal cylinder is presented to determine the effect of superheating on the heat transfer coefficient and film thickness in a pool. Findings from the present study will develop knowhow about the film formation and its role in enhancing the boiling heat transfer coefficient.am201

Effect of Continuous Renal Replacement Therapy on Outcome in Pediatric Acute Liver Failure

Objectives: To establish the effect of continuous renal replacement therapy on outcome in pediatric acute liver failure.Design: Retrospective cohort study.Setting: Sixteen-bed PICU in a university-affiliated tertiary care hospital and specialist liver centre.Patients: All children (0–18 yr) admitted to PICU with pediatric acute liver failure between January 2003 and December 2013.Interventions: Children with pediatric acute liver failure were managed according to a set protocol. The guidelines for continuous renal replacement therapy in pediatric acute liver failure were changed in 2011 following preliminary results to indicate the earlier use of continuous renal replacement therapy for both renaldysfunction and detoxification.Measurements and Main Results: Of 165 children admitted with pediatric acute liver failure, 136 met the inclusion criteria and 45 of these received continuous renal replacement therapy prior to transplantation or recovery. Of the children managed with continuous renal replacement therapy, 26 (58%) survived: 19 were successfully bridged to liver transplantation and 7 spontaneously recovered. Cox proportional hazards regression model clearly showed reducing hyperammonemia by 48 hours after initiating continuous renal replacement therapy significantly improved survival (HR, 1.04; 95% CI, 1.013-1.073; p = 0.004). On average, for every 10% decrease in ammonia from baseline at 48 hours, the likelihood of survival increased by 50%. Time to initiate continuous renal replacement therapy from PICU admission was lower in survivors compared to nonsurvivors (HR, 0.96; 95% CI, 0.916-1.007; p = 0.095). Change in practice to initiate early and high-dose continuous renal replacement therapy led to increased survival with maximum effect being visible in the first 14 days (HR, 3; 95% CI, 1.0-10.3; p = 0.063). Among children with pediatric acute liver failure who did not receive a liver transplant, use of continuous renal replacement therapy significantly improved survival (HR, 4; 95% CI, 1.5-11.6; p = 0.006).Conclusion: Continuous renal replacement therapy can be used successfully in critically ill children with pediatric acute liver failure to provide stability and bridge to transplantation. Inability to reduce ammonia by 48 hours confers poor prognosis. Continuous renal replacement therapy should be considered at an early stage to help prevent further deterioration and buy time for potential spontaneous recovery or bridge to liver transplantation