Notches

Economists have an instinctively negative reaction to any government program that creates a "notch," that is, a discontinuity in a budget constraint. For example, welfare programs like public housing are structured so that a finite lump of benefits is lost all at once when a household's income crosses a certain threshhold. Such notches deserve their bad reputation --they effectively impose a high marginal tax rate over a small income range, which no doubt discourages work and promotes welfare dependency. However,this paper argues that in other contexts, tax and subsidy plans with notches should at least be considered as serious contenders when public policy seeks to encourage or discourage some activity. Using simulations,we show how notch schemes can dominate traditional linear schemes using a standard efficiency criterion.

Will the Real Excess Burden Please Stand Up? (Or, Seven Measures in Search of a Concept)

It is well understood that a tax which distorts relative prices generates a welfare cost or "excess burden" in addition to any associated transfer of resources, but there remains considerable controversy and confusion with respect to procedures for measuring this excess burden. The purpose of this paper is to clarify matters concerning what is one of the most basic concepts in welfare economics. We describe and evaluate a number of alternative conceptual experiments which might lie behind an excess burden calculation, showing how these notions can be represented graphically and algebraically and how they can be approximated numerically.

Suramin inhibits the early effects of PLA(2) neurotoxins at mouse neuromuscular junctions: a twitch tension study

Several phospholipase A(2) (PLA(2)) neurotoxins from snake venoms can affect acetylcholine release at the neuromuscular junction. In isolated nerve-muscle preparations three distinct phases have been described for this phenomenon: An initial transient decrease in twitch tension; a second facilitatory phase during which twitch height is greater than control twitch height; and the last phase which causes a reduction in twitch height that finally results in paralysis. Suramin has been reported to inhibit the toxic effects of β-bungarotoxin and another PLA(2) neurotoxin, crotoxin in vitro and in vivo. We have further examined the effects of suramin on the three phases of the effects of the presynaptic PLA(2) neurotoxins β-bungarotoxin, taipoxin and ammodytoxin on mouse phrenic nerve-hemidiaphragm preparations. When preparations were pre-treated with suramin (0.3mM), the early biphasic effects (depression followed by facilitation) were abolished, and the time taken for final blockade induced by β-bungarotoxin, taipoxin and ammodytoxin A was significantly prolonged. In contrast, suramin did not significantly affect the facilitation induced by the potassium channel blocking toxin dendrotoxin I when applied under the same conditions. In addition, application of 0.3mM suramin did not prevent the facilitatory actions of 3,4-diaminopyridine (3,4-DAP) and tetraethylammonium chloride (TEA). Overall, the mechanism whereby suramin reduces the effects of PLA(2) neurotoxins remains elusive. Since suramin reduces both enzyme-dependent and enzyme-independent effects of the toxins, suramin is not acting as a simple enzyme inhibitor. Furthermore, the observation that suramin does not affect actions of standard K(+) channel blockers suggests that suramin does not stabilise nerve terminals

Efecto inhibidor del extracto acuoso de hojas de Persea americana Mill y sus fracciones sobre PTP1B como diana terapéutica para la diabetes tipo 2

Persea Americana Mill (Lauraceae), is a popular plant in Cuba due to its nutritional and medicinal properties. The fruit of the plant is commonly known as avocado. The leaves of Persea americana Mill have been popularly used in the treatment of diabetes in countries in Latin America and Africa. The present study is aimed to explore one of the underlying mechanisms that mediate the antidiabetic efficacy of Persea americana Mill. The aqueous extract from the leaves of the plant and its fractions were evaluated on the inhibitory activity of the protein tyrosine phosphatase 1B (PTP1B) as target of type 2 diabetes. The results revealed that aqueous extract from P americana inhibited the enzymatic activity of PTP1B in an extract concentration dependent manner, resulting mainly active the most polar fraction. The present research demonstrated that aqueous extract from P americana and polar fraction (PaF10) have promissory antidiabetic properties mediated by PTP1B, which is a relevant mechanism involved on insulin resistance in type 2 diabetes

Four-part differential leukocyte count using μflow cytometer

This paper reports the four-part differential leukocyte count (DLC) of human blood using a MEMS microflow (μflow) cytometer. It is achieved with a two-color laser-induced fluorescence (LIF) detection scheme. Four types of leukocytes including neutrophils, eosinophils, lymphocytes and monocytes are identified in blood samples, which are stained by fluorescein isothiocyanate (FITC) and propidium iodide (PI). The DLC results show good correlation with the count from a commercial hematology analyzer. The whole system is also implemented into a portable instrument for space application

Political Engagement and the Scottish Referendum : Supply or Demand Explanations?

Non peer reviewedPublisher PD

Testing the Validity of Standard Representative Agent Import Demand Systems

Demand and Price Analysis, International Relations/Trade,