Foreign aid and business bottlenecks : a study of aid effectiveness

This paper proposes a new framework to analyze aid effectiveness. Using World Bank firm survey data and OECD aid flow data, the authors analyze whether aid targets areas that firms in developing countries have identified as obstacles for their growth and whether aid actually improves firms'perceptions of those areas. The analysis finds that aid does target the areas that firms have identified as obstacles; aid funding trade related projects is particularly effective in targeting the correct countries. For the most part, aid has a positive impact on improving firms'perceptions, particularly in the business environment. And for each target area, smaller aid disbursements tend to be more effective at improving firm perceptions than larger disbursements.Environmental Economics&Policies,Development Economics&Aid Effectiveness,Disability,Gender and Health,School Health

Scale and texture in digital image classification

This thesis is a theoretical and empirical study on textural properties of digital images. Spatial information exists at a hierarchy of scales and texture is a consequence of the objects in that hierarchy. Within-class texture results from the spatial arrangement of objects at the next finer level in the hierarchy than the informational class. Between-class texture results from spectral differences between adjacent classes and is most obvious near class edges, especially for smooth classes. In rough classes between-class variance may not differ much from within-class variance. Errors in classifications using texture, therefore, are most likely associated with, class edges; however, investigators often avoid edges in evaluating texture or classification.;The window sizes needed to produce a stable texture measure are often large. Experiments with ADAR 1-meter data suggest that windows of 50 to 300 meters are necessary. Small windows are required to minimize edge effects. This is inherently contradictory as windows used to produce stable texture measures also produce a large edge effect.;Experiments with simulated data showed that separability of classes increased when texture was used in addition to spectral information. Separability of texture also improved with larger scale windows. This improvement was over-estimated when pixels were chosen away from class edges. The ADAR data showed that separability of the interiors of classes improved with the addition of texture, but for the class as a whole, the class separability actually fell. Maximum Likelihood classification of the ADAR data demonstrated the effect of edges and multiple scales in reducing the accuracy of classification incorporating texture

How to Evaluate your Question Answering System Every Day and Still Get Real Work Done

In this paper, we report on Qaviar, an experimental automated evaluation system for question answering applications. The goal of our research was to find an automatically calculated measure that correlates well with human judges' assessment of answer correctness in the context of question answering tasks. Qaviar judges the response by computing recall against the stemmed content words in the human-generated answer key. It counts the answer correct if it exceeds agiven recall threshold. We determined that the answer correctness predicted by Qaviar agreed with the human 93% to 95% of the time. 41 question-answering systems were ranked by both Qaviar and human assessors, and these rankings correlated with a Kendall's Tau measure of 0.920, compared to a correlation of 0.956 between human assessors on the same data.Comment: 6 pages, 3 figures, to appear in Proceedings of the Second International Conference on Language Resources and Evaluation (LREC 2000

A new species of \u3ci\u3eNeostenoptera\u3c/i\u3e (Diptera: Cecidomyiidae: Winnertziinae) from eastern North America

A new species of paedogenetic gall midge, Neostenoptera appalachiensis sp. nov., (Diptera: Cecidomyiidae: Winnertziinae: Heteropezini) from the eastern United States is described and illustrated, and pertinent collection and biological data are also provided. It is compared to its congeners, N. kiefferi (Meunier), a subfossil described from African copal, and N. congoensis Gagné, from the Congo. This rare, exciting discovery is the first record of the genus Neostenoptera in the New World. While conducting research in Great Smoky Mountains National Park (GSMNP) (North Carolina and Tennessee, USA) (Ferro et al. 2012), MLF collected numerous unidentifi able fl ies as bycatch from an emergence chamber used to collect beetles (Coleoptera) from dead wood. A specimen was photographed and placed on Bugguide.net under the title “Mystery Fly” (Fig. 1) (bugguide.net/node/view/786101/). Several years later, JDP noticed the image and thought it bore a resemblance to the paedogenetic Neostenoptera Meunier (1902) in the subfamily Winnertziinae (Gagné and Jaschhof 2014). Neostenoptera (Diptera: Cecidomyiidae: Winnertziinae: Heteropezini) is otherwise known from two African species, N. kiefferi (Meunier, 1901) described from African copal, a subfossil resin (Grimaldi 1996), and N. congoensis Gagné (1979) described from specimens collected in a Malaise trap in the People’s Republic of the Congo. This new species represents the fi rst record of this unusual genus in North America. Upon contacting Raymond J. Gagné, Systematic Entomology Laboratory, USDA, Washington, DC about our discovery, he notifi ed us that the USNM collection had some additional specimens of Neostenoptera from the southeastern United States that we might like to study. We found these to be the same species as the specimens from GSMNP. The specimens loaned to us from the USNM were invaluable as they enabled us to see certain characters obscured in our original slide preparations

A new species of \u3ci\u3eNeostenoptera\u3c/i\u3e (Diptera: Cecidomyiidae: Winnertziinae) from eastern North America

A new species of paedogenetic gall midge, Neostenoptera appalachiensis sp. nov., (Diptera: Cecidomyiidae: Winnertziinae: Heteropezini) from the eastern United States is described and illustrated, and pertinent collection and biological data are also provided. It is compared to its congeners, N. kiefferi (Meunier), a subfossil described from African copal, and N. congoensis Gagné, from the Congo. This rare, exciting discovery is the first record of the genus Neostenoptera in the New World. While conducting research in Great Smoky Mountains National Park (GSMNP) (North Carolina and Tennessee, USA) (Ferro et al. 2012), MLF collected numerous unidentifi able fl ies as bycatch from an emergence chamber used to collect beetles (Coleoptera) from dead wood. A specimen was photographed and placed on Bugguide.net under the title “Mystery Fly” (Fig. 1) (bugguide.net/node/view/786101/). Several years later, JDP noticed the image and thought it bore a resemblance to the paedogenetic Neostenoptera Meunier (1902) in the subfamily Winnertziinae (Gagné and Jaschhof 2014). Neostenoptera (Diptera: Cecidomyiidae: Winnertziinae: Heteropezini) is otherwise known from two African species, N. kiefferi (Meunier, 1901) described from African copal, a subfossil resin (Grimaldi 1996), and N. congoensis Gagné (1979) described from specimens collected in a Malaise trap in the People’s Republic of the Congo. This new species represents the fi rst record of this unusual genus in North America. Upon contacting Raymond J. Gagné, Systematic Entomology Laboratory, USDA, Washington, DC about our discovery, he notifi ed us that the USNM collection had some additional specimens of Neostenoptera from the southeastern United States that we might like to study. We found these to be the same species as the specimens from GSMNP. The specimens loaned to us from the USNM were invaluable as they enabled us to see certain characters obscured in our original slide preparations

Cargo adaptors regulate stepping and force generation of mammalian dynein-dynactin.

Cytoplasmic dynein is an ATP-driven motor that transports intracellular cargos along microtubules. Dynein adopts an inactive conformation when not attached to a cargo, and motility is activated when dynein assembles with dynactin and a cargo adaptor. It was unclear how active dynein-dynactin complexes step along microtubules and transport cargos under tension. Using single-molecule imaging, we showed that dynein-dynactin advances by taking 8 to 32-nm steps toward the microtubule minus end with frequent sideways and backward steps. Multiple dyneins collectively bear a large amount of tension because the backward stepping rate of dynein is insensitive to load. Recruitment of two dyneins to dynactin increases the force generation and the likelihood of winning against kinesin in a tug-of-war but does not directly affect velocity. Instead, velocity is determined by cargo adaptors and tail-tail interactions between two closely packed dyneins. Our results show that cargo adaptors modulate dynein motility and force generation for a wide range of cellular functions

A new species of \u3ci\u3eNeostenoptera\u3c/i\u3e Meunier (Diptera: Cecidomyiidae: Winnertziinae) from Hawai‘i

A new paedogenetic midge (Diptera: Cecidomyiidae: Winnertziinae: Heteropezini) from O‘ahu Island, Hawai‘i, Neostenoptera hawaiiensis Plakidas, Nguyen, and Ferro, new species, is described and illus­trated. A key to all species in the genus is provided. Specimens were emergent from deadwood gathered at Waimea Arboretum and Botanical Garden. Neostenoptera appalachiensis Plakidas and Ferro were collected from the same set of samples in Hawai‘i, and additional specimens are reported from Georgia and South Carolina, three new state records. The discovery of two paedogenetic midges in Hawai‘i poses a unique set of questions as to their possible mode of arrival on an island ecosystem. We briefly address the possibility that both species are simply “hitchhikers” that went undetected at ports of entry

Hibiscus acid from hibiscus sabdariffa (malvaceae) has a vasorelaxant effect on the rat aorta

Hibiscus sabdariffa (Malvaceae) is a plant that is widely recognised for its antihypertensive properties; however the constituent(s) responsible for this biological activity are presently unknown. The aim of this study was to identify the potential compounds that are responsible for the vasorelaxant activity of H. sabdariffa. Thereafter, the mechanisms involved in producing the vasorelaxation were investigated. The plant was extracted consecutively with hexane, ethyl acetate and methanol. The methanolic extract was subjected to bioassay-guided fractionation in order to isolate pure compounds that possessed vasorelaxant activity. The vascular effects of the pure compounds were studied on the rat aorta in vitro using myography techniques. Hibiscus acid produced a concentration-dependent relaxation of the rat aorta pre-contracted with either phenylephrine (3 μM) or KCl (60 mM), irrespective of the presence of the endothelium. When the tissue was pre-contracted with phenylephrine, the concentration required to produce 50% relaxation (IC50), was 0.09 ± 0.01 mg/ml. Hibiscus acid had no effect on the phasic contraction induced by phenylephrine in Ca2+-free physiological solution; but it did affect the component of the contraction that is due to Ca2+ influx. In parallel studies, garcinia acid, a diastereoisomer of hibiscus acid, was found to have an almost identical vasorelaxant effect. The vasorelaxant action of both compounds is most likely due to the inhibition of Ca2+ influx via voltage-dependent Ca2+ channels

The inhibitory effect of Haloxylon salicornicum on contraction of the mouse uterus

Haloxylon salicornicum (H. salicornicum) is a plant that is frequently taken as a tea by Bedouin women in Egypt who are experiencing difficulties during pregnancy, as well as to provide relief from dysmenorrhoea. Despite its medical use, there has been no detailed evaluation of the effect of this plant on uterine tissue. Therefore, the initial aim of this study was to determine whether H. salicornicum affected the contraction of the mouse uterus in vitro. The crude aqueous extract of H. salicornicum was found to inhibit the spontaneous contractions of the uterus, with the effect being rapid in onset and completely reversible upon washout. Subsequent purification of the plant extract resulted in the identification of synephrine and Nmethyltyramine, both of which were found to have inhibitory effects on the spontaneous contractions of the uterus. The EC50 for the purified constituent identified as synephrine was 0.82 ± 0.24 g/ml. The inhibitory activity of crude H. salicornicum, as well as the isolated constituents, could be prevented by pretreatment of the uterus with the -adrenoceptor antagonist propranolol. In conclusion, the use of H. salicornicum during pre-term labour appears to be justified and its pharmacologic effect is consistent with it acting as a -adrenoceptor agonist

The inhibitory effect of Haloxylon salicornicum on contraction of the mouse uterus

Haloxylon salicornicum (H. salicornicum) is a plant that is frequently taken as a tea by Bedouin women in Egypt who are experiencing difficulties during pregnancy, as well as to provide relief from dysmenorrhoea. Despite its medical use, there has been no detailed evaluation of the effect of this plant on uterine tissue. Therefore, the initial aim of this study was to determine whether H. salicornicum affected the contraction of the mouse uterus in vitro. The crude aqueous extract of H. salicornicum was found to inhibit the spontaneous contractions of the uterus, with the effect being rapid in onset and completely reversible upon washout. Subsequent purification of the plant extract resulted in the identification of synephrine and Nmethyltyramine, both of which were found to have inhibitory effects on the spontaneous contractions of the uterus. The EC50 for the purified constituent identified as synephrine was 0.82 ± 0.24 g/ml. The inhibitory activity of crude H. salicornicum, as well as the isolated constituents, could be prevented by pretreatment of the uterus with the -adrenoceptor antagonist propranolol. In conclusion, the use of H. salicornicum during pre-term labour appears to be justified and its pharmacologic effect is consistent with it acting as a -adrenoceptor agonist