The impact of individual retirement accounts on savings

Bills to expand individual retirement accounts have been introduced in both houses of Congress this year. While proponents argue that these accounts can help reverse the nation's declining saving rate, recent economic research suggests that the effect of the accounts on savings is in fact quite small.Individual retirement accounts ; Saving and investment

Facial behaviour of analytic functions on the bidisk

We prove that if $\phi$ is an analytic function bounded by 1 on the bidisk and $\tau$ is a point in a face of the bidisk at which $\phi$ satisfies Caratheodory's condition then both $\phi$ and the angular gradient $\nabla\phi$ exist and are constant on the face. Moreover, the class of all $\phi$ with prescribed $\phi(\tau)$ and $\nabla\phi(\tau)$ can be parametrized in terms of a function in the two-variable Pick class. As an application we solve an interpolation problem with nodes that lie on faces of the bidisk.Comment: 18 pages. We have replaced an erroneous proof of Theorem 5.4(1) by a valid proo

An economic analysis of the effects of production risk on the use and management of common-pool rangelands

Non-PRIFPRI

Voltage-dependent Block of the Cystic Fibrosis Transmembrane Conductance Regulator Cl- Channel by Two Closely Related Arylaminobenzoates

The gene defective in cystic fibrosis encodes a Cl- channel, the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR is blocked by diphenylamine-2-carboxylate (DPC) when applied extracellularly at millimolar concentrations. We studied the block of CFTR expressed in Xenopus oocytes by DPC or by a closely related molecule, flufenamic acid (FFA). Block of whole-cell CFTR currents by bath-applied DPC or by FFA, both at 200 µM, requires several minutes to reach full effect. Blockade is voltage dependent, suggesting open-channel block: currents at positive potentials are not affected but currents at negative potentials are reduced. The binding site for both drugs senses ~40% of the electric field across the membrane, measured from the inside. In single-channel recordings from excised patches without blockers, the conductance was 8.0 ± 0.4 pS in symmetric 150 mM Cl^-. A subconductance state, measuring ~60% of the main conductance, was often observed. Bursts to the full open state lasting up to tens of seconds were uninterrupted at depolarizing membrane voltages. At hyperpolarizing voltages, bursts were interrupted by brief closures. Either DPC or FFA (50 µM) applied to the cytoplasmic or extracellular face of the channel led to an increase in flicker at V_m =-100 mV and not at V_m = +100 mV, in agreement with whole-cell experiments. DPC induced a higher frequency of flickers from the cytoplasmic side than the extracellular side. FFA produced longer closures than DPC; the FFA closed time was roughly equal (~ 1.2 ms) at -100 mV with application from either side. In cell-attached patch recordings with DPC or FFA applied to the bath, there was flickery block at V_m = -100 mV, confirming that the drugs permeate through the membrane to reach the binding site. The data are consistent with the presence of a single binding site for both drugs, reached from either end of the channel. Open-channel block by DPC or FFA may offer tools for use with site-directed mutagenesis to describe the permeation pathway

Super champions, champions and almosts: Important differences and commonalities on the rocky road

The real-world experiences of young athletes follow a non-linear and dynamic trajectory and there is growing recognition that facing and overcoming a degree of challenge is desirable for aspiring elites and as such, should be recognized and employed. However, there are some misunderstandings of this “talent needs trauma” perspective with some research focusing excessively or incorrectly on the incidence of life and sport challenge as a feature of effective talent development. The objective of the study was to examine what factors associated with such “trauma” experiences may or may not discriminate between high, medium and low achievers in sport, classified as super-champions, champions or almosts. A series of retrospective interviews were used with matched triads (i.e., super-champions, champions or almosts) of performers (N = 54) from different sports. Data collection was organized in three phases. In the first phase, a graphic time line of each performer’s career was developed. The second phase explored the specific issues highlighted by each participant in a chronological sequence. The third phase was a retrospective reflection on “traumatic” motivators, coach/significant other inputs and psychological challenges experienced and skills employed. Data suggested qualitative differences between categories of performers, relating to several perceptual and experiential features of their development. No evidence was found for the necessity of major trauma as a feature of development. There was a lack of discrimination across categories of performers associated with the incidence of trauma and, more particularly, life or non-sport trauma. These findings suggest that differences between levels of adult achievement relate more to what performers bring to the challenges than what they experience. A periodized and progressive set of challenge, preceded and associated with specific skill development, would seem to offer the best pathway to success for the majority

Jurors’ perceptions of forensic science expert witnesses:Experience, qualifications, testimony style and credibility

The judicial system calls upon expert witnesses to testify in court when complex or specialized knowledge, beyond that of the lay person, is needed to interpret the evidence. Previous research has indicated that particular traits of the expert witness can affect their credibility in the eyes of the jury, however most of this research has been undertaken using mock jurors. In contrast, this study investigated the perceptions of real jurors. In particular, the research focused on the juror's perception of the forensic scientists’ expertise and credibility during testimony in homicide cases. Data was gathered from jurors after nine homicide trials using both questionnaire (n = 29) and direct one to one interviews (n = 22). The jurors defined what they thought an expert witness was and what attributes were important in a forensic scientist. Jurors suggested that the expert witness's education and years of experience were more important than certification or laboratory accreditation. The jurors’ perceptions of the credibility of the expert was based upon the academic qualifications of the expert, the confidence they portrayed in answering the questions ask of them, their demeanor and their status of being government employee. The use of narrative language and demonstrative aids by the forensic science expert witness to explain the evidence was explored. Jurors described a deeper understanding as a result of narrative testimony and this was reported to be a key factor in the juror's acceptance that the witness was credible.</p

Effective Radii and Color Gradients in Radio Galaxies

We present de Vaucouleurs' effective radii in B and R bands for a sample of Molonglo Reference Catalogue radio galaxies and a control sample of normal galaxies. We use the ratio of the scale lengths in the two bands as an indicator to show that the radio galaxies tend to have excess of blue color in their inner region much more frequently than the control galaxies. We show that the scale length ratio is a useful indicator of radial color variation even when the conventional color gradient is too noisy to serve the purpose.Comment: 11 pages, 4 figures, (LaTeX: aaspp4, epsfig), to appear in ApJL 199

Putting the bumps in the rocky road: Optimising the pathway to excellence

There seems to be general agreement on the importance of challenge for effective development on the athlete pathway. What seems less coherent, however, are ideas on how much, when and how this challenge should be used. Reflecting our own experience as applied practitioners and our ongoing research, we offer a perspective on this work from a practitioner stance. The literature suggests that differences between levels of adult achievement relate more to what performers bring to the challenges than what they experience. Therefore, it is essential that young athletes have the opportunity to develop psycho-behavioural and coping skills, and have adequate social support, to ensure that adversity is interpreted as a positive growth experience. A periodized and progressive set of challenge, preceded with specific skill development, would seem to offer the best pathway to success. The importance of preparing athletes for challenges, supporting them through the experience, and then encouraging positive evaluation and reflection is key to successful outcome. Finally, we offer some suggestions, structures and systems which can be used to support the skill-based approach promoted

The effect of environmental variability on livestock and land-use management: The Borana plateau, southern Ethiopia

The Borana people are the predominant ethnic group on the Borana Plateau in southern Ethiopia. Though traditionally transhumant pastoralists, they have recently increased their reliance on crops. Rainfall in the region averages between 353 mm to 873 mm; variability in rainfall is quite high, with coefficients of variation ranging from.21 to.68. The past decade has witnessed a dramatic increase in land allocated to crops, and land in pastures that are either becoming privatised, or accessible to only a small sub-group of people. In this paper, we derive an empirical model of stocking rates and land allocation, which is then used to estimate the effects of exogenous parameters on stocking densities, land allocated to crops, and land allocated to private pastures. Results indicate the following: a) regions with high coefficients of variation in rainfall have lower livestock densities and less land allocated to crops, b) communities with greater numbers of households and higher population densities have larger indices of non-cooperation, higher stock densities, and more land allocated to crops, c) heterogeneity within a community, measured by the distribution of wealth levels, is positively related to an index of non-cooperation, and to higher stock densities, d) higher relative prices of livestock and shorter distances to market are associated with greater stock densities as well as greater land allocated to crops, e) the greater is mobility into an area, the higher are stock densities, and the lower is the cooperation level, whereas outward mobility by community members has no effect on either stock densities or the level of cooperation reached, f) the proportion of members engaged in wage work outside has a significant negative effect on the ability of the community to cooperate. Outside wage work also increases land allocated to crops, but has a significant negative effect on land allocated to private pastures, and g) the greater is the index of non-cooperation, the higher are stock densities and the greater is land allocated to crops.

miR-375 gene dosage in pancreatic β-cells: implications for regulation of β-cell mass and biomarker development

MicroRNAs play a crucial role in the regulation of cell growth and differentiation. Mice with genetic deletion of miR-375 exhibit impaired glycemic control due to decreased β-cell and increased α-cell mass and function. The relative importance of these processes for the overall phenotype of miR-375KO mice is unknown. Here, we show that mice overexpressing miR-375 exhibit normal β-cell mass and function. Selective re-expression of miR-375 in β-cells of miR-375KO mice normalizes both, α- and β-cell phenotypes as well as glucose metabolism. Using this model, we also analyzed the contribution of β-cells to the total plasma miR-375 levels. Only a small proportion (≈1 %) of circulating miR-375 originates from β-cells. Furthermore, acute and profound β-cell destruction is sufficient to detect elevations of miR-375 levels in the blood. These findings are supported by higher miR-375 levels in the circulation of type 1 diabetes (T1D) subjects but not mature onset diabetes of the young (MODY) and type 2 diabetes (T2D) patients. Together, our data support an essential role for miR-375 in the maintenance of β-cell mass and provide in vivo evidence for release of miRNAs from pancreatic β-cells. The small contribution of β-cells to total plasma miR-375 levels make this miRNA an unlikely biomarker for β-cell function but suggests a utility for the detection of acute β-cell death for autoimmune diabetes