Explaining variations in the commonality of informal sector competition across Latin American and the Caribbean countries

To advance understanding of the relationship between entrepreneurship and the informal sector, the aim of this paper is to evaluate and explain variations in the extent to which formal enterprises witness competition from unregistered or informal enterprises across Latin American and Caribbean countries. Reporting World Bank Enterprise Survey (WBES) data on 31 Latin American and Caribbean countries, this reveals that two-thirds (65.5 percent) of formal enterprises witness competition from informal sector enterprise. To explain the cross-country variations, four competing theories are evaluated, which variously view the prevalence of the informal sector to be determined by either: economic under-development (modernization theory); high taxes and state over-interference (neo-liberal theory); too little state intervention (political economy theory), or an asymmetry between the laws and regulations of formal institutions and the unwritten socially shared rules of informal institutions (institutional theory). A probit regression analysis confirms the modernization, political economy and institutional theories, but not the neo-liberal theory. Beyond economic under-development, therefore, it is too little state intervention and whether the laws and regulations developed by governments are in symmetry with the norms, values and beliefs of entrepreneurs. The paper concludes by discussing the theoretical and policy implications of these findings

The coronavirus endoribonuclease Nsp15 interacts with retinoblastoma tumor suppressor protein

Coronaviruses encode an endoribonuclease, Nsp15, which has a poorly defined role in infection. Sequence analysis revealed a retinoblastoma protein-binding motif (LXCXE/D) in the majority of the Nsp15 of the severe acute respiratory syndrome coronavirus (SARS-CoV) and its orthologs in the alpha and beta coronaviruses. The endoribonuclease activity of the SARS-CoV Nsp15 (sNsp15) was stimulated by retinoblastoma protein (pRb) in vitro, and the two proteins can be coimmunoprecipitated from cellular extracts. Mutations in the pRb-binding motif rendered sNsp15 to be differentially modified by ubiquitin in cells, and cytotoxicity was observed upon its expression. Expression of the sNsp15 in cells resulted in an increased abundance of pRb in the cytoplasm, decreased overall levels of pRb, an increased proportion of cells in the S phase of the cell cycle, and an enhanced expression from a promoter normally repressed by pRb. The endoribonuclease activity of the mouse hepatitis virus (MHV) A59 Nsp15 was also increased by pRb in vitro, and an MHV with mutations in the LXCXE/D-motif, named vLC, exhibited a smaller plaque diameter and reduced the virus titer by ~1 log. Overexpression of pRb delayed the viral protein production by wild-type MHV but not by vLC. This study reveals that pRb and its interaction with Nsp15 can affect coronavirus infection and adds coronaviruses to a small but growing family of RNA viruses that encode a protein to interact with pRb

New Detections of Optical Emission from Kiloparsec-scale Quasar Jets

We report initial results from the detection of optical emission in the arcsecond-scale radio jets of two quasars utilizing images from the {\it Hubble Space Telescope} archive. The optical emission has a very knotty appearance and is consistent with synchrotron emission from highly relativistic electrons in the jet. Combining these observations with those of previously reported features in other quasars, an emerging trend appears to be that their radio-to-optical spectral indices are steeper than those of similar features in jets of lower power radio sources.Comment: 4 pgs, 2 figs, Proc of The Physics of Relativistic Jets in the Chandra and XMM Era workshop, eds. G. Brunetti, D.E. Harris, R.M. Sambruna, and G. Setti, submitted to New Astronomy Review. Quality of figure 1 degraded to fit into preprint server. Includes elsart.cls fil

Motor Task Processing After Constraint- Induced Movement Therapy in Children With Cerebral Palsy: A Case Series

Constraint-induced movement therapy (CIMT) has shown positive results in children with hemiplegic cerebral palsy (CP). However, studies on neural basis of such functional gains are limited. This study reports the event-related potential (ERP) changes in two children with hemiplegic CP after receiving CIMT for three weeks. Both cases were nine years old, had a diagnosis of left hemiplegic CP, had normal intelligence, and were able to extend the wrist at least 20° and the metacarpophalangeal joint at least 10° from full flexion. Before and after the three-week intervention, the children participated in ERP sessions with a choice reaction task to capture the changes in neural mechanism after intervention. Both children exhibited improvement in reaction time (RT) in both hand tasks after the intervention. The improvement was larger in the affected hand than the unaffected hand. Improved accuracy rate (AC) and shortened P300 latencies in the affected hand were also demonstrated in both cases. Topographical maps showed that in centro-parietal regions, patterns shifted from central and left-lateralized to more central and right-lateralized. CMIT was a useful method in improving upper limb function in our cases

PHP61 The Financial Impacts of Pharmacist Intervention in Inpatient Department of a Local Hospital in Taiwan

Morphometric analysis of S. mortenseni. (DOC 44 kb

A Co-axial Multi-tube Heat Exchanger Applicable for a Geothermal ORC Power Plant

AbstractThe study proposes a Co-axial multi-tube heat exchanger (CMTHE) applicable to geothermal heat extraction. The heat exchanger is integrated with a 50kW geothermal ORC power plant having a working fluid of R-245fa. Two field tests were performed to examine the system response of the ORC system subject to change of CMTHE. In case 1 where the flow rate in the shell-side of CMTHE is maintained, the pressure variation in the shell-side of CMTHE casts minor variations on heat extraction, ORC power generation, and ORC efficiency during the transient. Moreover, the effect of pressure has barely any influence of the final states of heat extraction, ORC power generation, and ORC efficiency. In case 2 where the pressure is preserved in the CMTHE, it is found that a decrease of flow rate in the CMTHE results in degradation of heat extraction, ORC power generation and ORC system efficiency. On the contrary, increasing the flow rate in the CMTHE leads to a rise of heat extraction, ORC power generation and ORC system efficiency. Unlike that in case 1, the effect of flow rate has a detectable effect on the final states of heat extraction, ORC power generation, and ORC efficiency

A comparison of block and semi-parametric bootstrap methods for variance estimation in spatial statistics

Efron (1979) introduced the bootstrap method for independent data but it cannot be easily applied to spatial data because of their dependency. For spatial data that are correlated in terms of their locations in the underlying space the moving block bootstrap method is usually used to estimate the precision measures of the estimators. The precision of the moving block bootstrap estimators is related to the block size which is difficult to select. In the moving block bootstrap method also the variance estimator is underestimated. In this paper, first the semi-parametric bootstrap is used to estimate the precision measures of estimators in spatial data analysis. In the semi-parametric bootstrap method, we use the estimation of the spatial correlation structure. Then, we compare the semi-parametric bootstrap with a moving block bootstrap for variance estimation of estimators in a simulation study. Finally, we use the semi-parametric bootstrap to analyze the coal-ash data

Magnetic Field Trapping High-T_c Superconductors

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Generation and Evolution of Spin Entanglement in NRQED

A complete analysis on the generation of spin entanglement from NRQED is presented. The results of entanglement are obtained with relativistic correction to the leading order of (v/c)^2. It is shown that to this order the degree of entanglement of a singlet state does not change under time evolution whereas the triplet state can change.Comment: 8 pages, 1 figure, to appear in Phys. Rev.