Important Positive Effect Research Articles

Why do business groups continue to matter? A study of market failure and performance among Indian manufacturers

This paper explores the nature of the influence that business groups exert in shaping performance outcomes in emerging economies. Set in India, this study used a longitudinal research design to assess the independent and collective performance impact of group affiliation and diversification both before and after economic reforms were introduced in the country. Consistent with the institutional theory perspective, results show that in the pre-reform period the group structure exerted an important positive moderating effect on the diversification-performance relationship. However, these group benefits appear to persist even after many of the sources of market failure had started to decline rapidly. This persistence of group effect may be indicative of the continued relevance of non-diversification benefits of the group structure in emerging economies. It may also be indicative of the fairly slow process of building institutional infrastructure in emerging economies where reforms are seldom introduced en masse but more a series of continuing measures as was the case in India.

Faut-il concevoir les prospectus en fonction de la fidélité du client à l’enseigne ?

Cette etude evalue l’influence de l’attractivite de trois caracteristiques du prospectus – le prix, l’offre et le theme – sur son efficacite pour le distributeur. Les resultats d’une enquete exploratoire menee aupres de 958 individus mettent en evidence des mecanismes d’influence differents en fonction de la fidelite du client. Pour les clients fideles, l’attractivite percue des prix au sein du prospectus a un effet positif important sur l’achat de produits promus. Pour les clients occasionnels, la visite de l’enseigne et l’achat de produits promus en prospectus sont influences directement par l’attractivite percue des prix et indirectement par l’attractivite percue du theme du prospectus. Des recommandations sont formulees pour le distributeur afin d’optimiser la conception du prospectus en fonction du profil des clients.

Growth and Metal Uptake by Plants Grown in Mono- and Dual Culture in Metal-contaminated Soils

Plants are able to affect the mobility of heavy metals in the rhizosphere due to root exudates and other mechanisms resulting in a change in their phytoextraction ability. We tested separate (monoculture) and intercropping (dual culture) systems of hyperaccumulator Thlaspi caerulescens and accumulator tree Salix dasyclados in two soils with different levels of contamination. Intercropping did not significantly affect accumulation and removal of Cd, Pb, and Zn in moderately contaminated soil. Separately cropped S. dasyclados continuously died due to phytotoxicity of the highly contaminated soil. We indicated an important positive effect of intercropping in this soil. Intensive uptake of heavy metals by Thlaspi roots decreased relatively toxic concentrations in soil and improved the growth of S. dasyclados. The maximum limit of the phytoextraction potential of T. caerulescens was not reached at the extremely contaminated soil but the efficiency of the intercropping at the extremely contaminated soil still remains limited and alternative remediation techniques can be considered at this particular contaminated site.

A resource ratio model of the effects of changes in CO2 on woody plant invasion

It is expected that elevated CO2 levels may have an important positive effect on the dominance of woody plants over grasses in savannas and grasslands. I propose that these changes in the relative abundance of trees and shrubs over grasses may be explained by Tilman’s resource ratio models. This change will occur because C3 trees will have higher net photosynthetic rates than C4 grasses which predominate in savannas. This will cause trees to have higher growth rates than grasses. An additional factor in trees and shrubs with carbon-based defences (such as tannins or other polyphenols) is that they may be better defended and, thus, lose less material to herbivory. Consequently, trees and shrubs should invade savannas and grasslands because their R* values will be lower. I compare this model to another less parsimonious model based on fire and carbon storage and allocation. Although these models are not necessarily mutually exclusive, the resource ratio model may be differentiated from the fire-carbon model on the basis of the presence of fire and/or the sensitivity to elevations in global CO2 levels.

Measuring cycle efficiency and capacitance of chemically activated carbons in propylene carbonate

The cycle efficiency and capacitance of two KOH-activated carbons have been tested in 0.5M tetraethylammonium tetrafluoroborate in propylene carbonate (TEABF4/PC) under different conditions of temperature (room temperature and 70°C) and voltage (0–3V). The materials tested include a KOH-activated carbon before and after treatment with different acids and hydrogen at high temperature to remove most of the oxygen groups and inorganic impurities. Porous texture and surface chemistry characterization have been carried out before and after cycling to understand the changes in the properties of activated carbons during the cycles. It has been observed that the treatment with different acids and hydrogen at high temperature produces materials with higher cycling stability. The results point out that the observed electrode degradation is mainly due to some pore blockage caused by reaction of the solvent with the functional groups on the carbon. The blockage of porosity is higher for the sample with higher oxygen content, indicating that the treatment carried out to remove the oxygen groups has an important positive effect, giving electrodes with a much lower degradation under very aggressive conditions in a TEABF4/PC medium.

The rate of learning‐by‐doing: estimates from a search‐matching model

AbstractWe construct and estimate by maximum likelihood a job search model where wages are set by Nash bargaining and idiosyncratic productivity follows a geometric Brownian motion. The proposed framework enables us to endogenize job destruction and to estimate the rate of learning‐by‐doing. Although the range of the observations is not independent of the parameters, we establish that the estimators satisfy asymptotic normality. The structural model is estimated using Current Population Survey data on accepted wages and employment durations. We show that it accurately captures the joint distribution of wages and job spells. We find that the rate of learning‐by‐doing has an important positive effect on aggregate output and a small impact on employment. Copyright © 2009 John Wiley & Sons, Ltd.

Health demand and health determinants in China

This paper identifies health determinants in rural and urban China. Using the 2000 wave of the China Health and Nutrition Survey, we find that education has an important positive effect on health. We also find that regional location is an important determinant of health. Our results indicate that the self-reported health status is not significantly different between the urban and the rural population. Our study suggests that Chinese males have better health than females, and married persons have better health than single persons. We also find that rural residents who live in suburbs have worse health than those who live in remote villages.

Respective importance of ecological conditions and stand composition on Abies alba Mill. dominant height growth

In mixed stands, abiotic effects and interspecific interactions on tree height growth remain largely unknown. We investigated the effects of climate, nutrition and stand composition on silver fir ( Abies alba Mill.) height growth in the Vosges Mountains (northeastern France). Data were collected from 143 plots established on seven stand types of silver fir ( Abies alba Mill.): pure silver fir stands and six mixed stands of silver fir with Fagus sylvatica, Picea abies, Pinus sylvestris, Quercus petraea and Acer pseudoplatanus, along both elevation and nutritional gradients. Silver fir dominant height was characterised by the site index, which was related by multiple-regression analyses with measured nutritional variables, climatic variables and stand composition descriptors. The results showed that silver fir site index was significantly correlated with climate, nutrition and stand composition. Among climatic variables, elevation was responsible for a large portion of the site index variance ( R 2 = 0.13). Slope aspect showed an important positive effect of eastern oriented plots on silver fir site index, as did mild winter temperature. Variables related to water availability showed a positive effect on site index only at elevations below 600 m, where lower precipitations and higher temperatures lead to a water-limiting factor. Nutritional resources were the second factor determining silver fir site index by both nitrogen nutrition and protons and aluminium acidity or toxicity. An environmental model, including climatic and nutritional variables, explained 64% of site index variance with a standard error of 2.7 m. For equivalent sites, basal area of the dominant cohort, as well as basal area of conifer species, showed a positive effect on site index, while broadleaved basal area did not show any significant effect in addition to that of conifers. A final model including abiotic variables and conifer basal area explains 71% of site index variance with a standard error of 2.5 m in the study area. The search for ecological drivers of tree height that control access to light is of great importance in the context of environmental changes in predicting tree species relationships in mixed stands.

Residual effects of poultry litter on silage maize (Zea mays L.) growth and soil properties derived from volcanic ash

Poultry litter (PL) is a cheap alternative to conventional fertilizers. The use of PL in this way also reduces the environmental problems normally associated with its disposal. The residual effect of PL may reduce the amount of fertilizer (especially N fertilizer) required by subsequent crops. This study examines the residual effects of PL (with and without additional mineral fertilizer) on the properties of a volcanic ash soil and on silage maize (Zea mays) yields in central Chile. Poultry litter and mineral fertilizer were applied in 2002–2003 and their residual effects were determined in 2004–2006. The dry matter (DM) yield, nutrient balance and apparent nitrogen recovery efficiency (ANRE) of the silage maize were determined for each season, and the soil properties were analyzed at three depths (0–20, 20–40 and 40–60 cm) at the end of the third season. Crop yield showed a positive response to all fertilizer treatments. The residual effect, the nutrient balance, N uptake and ANRE also improved with fertilizer treatment, especially with the PL treatments. The average DM yield for the PL treatments was higher than that observed using mineral fertilizer by 2.8 and 1.2 Mg ha−1 in the third and fourth years, respectively. The ANRE was generally higher in the PL treatments, although it decreased over time (12.4 and 1.7% for the last 2 years, respectively). The mean ANREs for the mineral fertilizer treatment were 4.1 and 1.6% for the same years. The results suggest that the PL treatments had an important positive residual effect in terms of N supply. This should be taken into account when planning the next crop. After two annual applications of PL, slight increases were observed in soil NO3-N at a depth of 0–20 cm, and extractable P at depths of 20–40 cm and 40–60 cm. No other soil variables were significantly affected by any of the treatments. An additional source of K was found to be necessary to maintain an adequate soil K level.

Neutral Leaching of Low-Grade Pyrolusite with High Silica Content

Leaching studies of low-grade pyrolusite, containing 11.84% Mn with high silicon, were carried out using sodium sulfite as a reductant in ammonium sulfate medium. Various process parameters including temperature, leaching time, solid-liquid ratio, quantity of ammonium sulfate, as well as the amount of reducing agent were studied in detail. The manganese extraction yield was the response of the process. Temperature and reagent concentration exerted the most important positive effect on the manganese extraction. The optimized conditions showed that when the amount of reducing agent was a stoichonmetric amount, over 90% manganese extraction and the lowest impurities were achieved, the amount of heavy metal impurities in the manganese leaching liquid was less than 5 mg/L, and almost no iron and aluminum were extracted in 3 mom ammonium sulfate concentration at 100 °c in 45 min.

Magicians, Reputation Trolls, Tsunamis and Floods: Has Patent Protection for Financial Innovation Encouraged Financial Institution Creativity?

Before the watershed 1998 State Street decision in the United States, financial innovations were thought to be largely unpatentable. However that decision signalled a new financial patent flood (600+ per year since 2000) resulting from an application torrent (8,000+ patent applications per year since 1999) and followed by a patent litigation tsunami (3000+ actions in 2005 alone.) The article examines whether this new patent is likely to encourage financial innovation among globally competing financial institutions. Our tentative no answer follows evidence presented here and follows from conclusions reached in earlier work. Earlier we found that innovation has an important positive effect on financial institution common stock returns. When we rank firms by propensity to innovate, propensity to innovate is positively related to long run stock market returns. But to return a-greater-than-normal profit, financial innovation must be kept secret. In light of this, our question can be rephrased thus: Have the visible patent seekers been high-return innovators or low-return imitators? While these are still early days in the history of intellectual property protection in finance, the initial evidence supports our theory of secrecy and suggests the answer is that imitators have obtained more patents than innovators. However patent applicants can choose to hide their patent appeal from public view until the patent itself is issued. The vast majority of financial patent applications have been thus secreted. This is also consistent with the proposition that profitable financial innovations require secrecy We conclude with a summary of the negative implications of these developments for patents' effect on the propensity to innovate.

The Rate of Learning-By-Doing: Estimates from a Search-Matching Model

We construct and estimate by maximum likelihood an equilibrium search model where wages are set by Nash bargaining and idiosyncratic productivity follows a geometric Brownian motion. The proposed framework enables us to endogenize job destruction and to estimate the rate of learning-by-doing. Although the range of the observations is not independent of the parameters, we establish that the estimators satisfy asymptotic normality. The structural model is estimated using Current Population Survey data on accepted wages and employment durations. We show that it captures almost perfectly the joint distribution of wages and job spells. We find that the rate of learning-by-doing has an important positive effect on aggregate output and a small impact on employment.

Reproductive performance of crossbred and purebred male rabbits

Abstract The effect of buck genetic type and crossbreeding parameters on fertility and prolificacy were estimated using two rabbit sire lines and their reciprocal crosses. The relationship between the reproductive performance of inseminated multiparous does and several semen quality traits was also investigated. The semen characteristics evaluated were: pH (pH), mass and individual motility (MM, IM), percentage of viable spermatozoa (Vi), spermatozoa with normal apical ridge (NAR), normal spermatozoa (NSP), spermatozoa with morphological abnormalities of head (HAP), neck-midpiece (NAP), and tail (TAP), spermatozoa with the presence of proximal (PD) and distal (DD) cytoplasmic droplets. Fertility was analysed as a continuous trait (kindling rate) or as a binary trait (success or failure of kindling). In the first case, the analysis was performed using GLM procedures of SAS v.8 according to a model that included the fixed factors of buck genetic type, number of ejaculates per pool and week of insemination. In the second case, fertility was analysed using GENMOD procedures of SAS v.8 according to a mixed model including the same fixed factors as before plus the physiological status of the does and the permanent random effect of female. Number of kits born alive and number of stillborn were analysed with MIXED procedures of SAS v.8 with the same model used for the analysis of fertility as a binary trait. Estimates of the estimable functions of crossbreeding genetic parameters of the lines were obtained from the solutions of the corresponding models by generalized least squares using GLM, GENMOD and MIXED procedures. Crossbreeding parameters were estimated according to the model of Dickerson. A linear regression was used to determine the relationship between fertility and litter size and the semen characteristics evaluated. Significant differences in fertility were observed among buck genetic types, which were favourable to type R. Differences between lines in maternal genetic effects were relevant and favourable to type R for fertility. Individual heterosis was important but unfavourable for fertility. A slight correlation was obtained between all semen quality traits and fertility and prolificacy. Two multiple models were found for fertility, including NAP, IM, NSP, buck genetic type and Vi in one model or NAR in other model. Individual motility had an important positive effect, while NAP had a small negative effect. When MM, TAP and buck genetic type were included in a multiple model for the number of kits born alive, both MM and TAP had significant small effects. Individual motility and DD appeared to be related to number of kits stillborn, but only DD had a significant although negligible effect.

The impact of park trees on microclimate in urban areas

Trees in cities have an important positive effect on people’s lives. One such positive effect is the amelioration of microclimate. The aim of this research is to assess the correlation between parameters that affect the microclimate of parks during the summer. We measured air temperature, relative humidity and solar radiation in the sun and shade of the trees in urban parks in Thessaloniki, Greece. The results indicate that: the air (A) temperature reduction percentage (dTair%), air relative humidity increase (dTRh%), discontent index reduction percentage (DI%) (cooling effect) and solar radiation (L) percentage that passes through the trees’ foliage to their shade creates an exponential function of dA% = a.e-bL. These functions are also applicable to the limiting variation values of the parameters. If we use L = 0 (meaning Lightsh = 0, which is the case for an extremely dense tree), then the values that we expect from this particular parameter are the maximum possible. These maximum values are a characteristic feature of the parameter variation for this particular research area. These maximum values for the trees in the parks of Thessaloniki are: maxdTair% ≈ 24%, maxdRh% ≈ 41% and maxdDI% ≈16%.

Privatization of tubewells in North China: Determinants and impacts on irrigated area, productivity and the water table

Despite the rise in importance of the private sec- tor in the expansion of the use of groundwater in China and the potential implications this might have for production and poverty, little has been written about the effect of these phenomena on northern China's economy. In examining determinants of tubewell privatization and its impact on producers in northern China, data were collected using a community leader survey, carried out in 448 villages in six provinces in northern China. The results show that since 1990 collective ownership of tubewells has largely been replaced by private ownership. Increasing water scarcity, government grants and bank loans for tubewell investment and the declining investment capacity of China's local com- munities have led to the observed change in tubewell own- ership patterns. By far, the most important positive effect on income appears to be due to the expansion of newly ir- rigated area that has been fueled by the rise of private tube- wells. Many newly private tubewells also have begun to replace irrigation from surface water sources. While help- ing increase income and productivity, the rise of private tubewells also has contributed to the fall in groundwater levels.

Health Determinants in Urban China

This paper identifies health determinants in urban China applying the Grossman model. Using a wave of China Health and Nutrition Survey in 2000, we find that education has an important positive effect on health, and cost of health care services has a significantly negative impact. However, effects of wage rate and household income are insignificant. We also find that region is an important determinant of health. The body weight is also important, but unlike the finding in developed countries, under-weight instead of over-weight is a better predictor for poor health. Our results suggest that a male has better health than a female does, and a married couple has better health in urban China.

Quality and the nursing workforce: APNs, patient outcomes and health care costs

Quality in health care requires access, appropriate and acceptable treatment plans, responsible patient follow through, a workforce of sufficient numbers and qualification and agreement on health care quality indicators. The purpose of this article is to describe APN workforce and dose effects on quality, reflected in patient outcomes and health care costs with current quality indicators. Stakeholders measure “quality indicators” differently. Nursing practices are often absent in databases and systems of reimbursement. Research overwhelmingly indicates equal outcomes for physician and APN care plus value-added APN effects on use of preventive services, adjustment to illness, stress management, treatment compliance, satisfaction, and reduced emergency room visits and rehospitalizations. APN dose has an important positive effect on patient outcomes and healthcare costs. Research is needed on the level of APN dose, staff mix and use of APNs, and balance of physician and APN dose in different stages of patient health, illness, and recovery to achieve quality outcomes.

Full factorial design applied to intercalation of amines in lamellar titanium phenylphosphonate and titanium phenylarsonate

The intercalation of amines into titanium phenylphosphonate M(O 3PC 6H 5) 2 and titanium phenylarsonate M(O 3AsC 6H 5) 2 was investigated through batch and back-titration processes. Amine insertion in both layered lamellar inorganic matrices, measured by the number of moles of intercalated agent, was optimized using a complete factorial design based on two levels and four factors. The effects of solvent, ethanol and acetonitrile, neutral organic base, ethyl and propylamines, H 3C(CH 2) n NH 2 ( n=1, 2), and material mass, 30 and 40 mg, on amine insertion in both lamellar inorganic matrices was optimized using a full factorial design. Important positive effect values, 0.40×10 −3 and 0.69×10 −3 mol g −1 were observed for inorganic material and solvent whereas a negative effect, −0.33×10 −3 mol g −1 was observed for material mass. Two significant but less important binary interactions were also observed. The use of either ethyl or propylamine does not appear to affect the quantity of amine insertion. Recommended experimental conditions for maximum amine insertion obtained from this factorial design are 30 mg of titanium phenylarsonate in acetonitrile solvent using either of the studied amines.

Compactibility of agglomerated mixtures of calcium carbonate and microcrystalline cellulose

The tablet tensile strength ( T) of agglomerated mixtures of microcrystalline cellulose—Avicel PH 102 (MC), calcium carbonate (CC) and polyvinylpyrrolidone (Povidone, PVP), lubricated with magnesium stearate (MS), and formed under a compaction pressure ( P c) ranging up to 618 MPa has been determined. The compactibility was defined through: ln(− ln(1−T/T max ))= Slope× ln P c + Intercept . MC/CC mixtures added of an agglutinant, before and after lubrication, show an important positive effect on their tablet tensile strength compared to a lineal relationship. This positive effect becomes smaller with decreasing compaction pressures. By different mixing methods, the higher the mixing efficiency the higher the compactibility, following the order: spray-dried>wet massing>tumble mixing. The compactibility of MC/CC/PVP spray-dried mixtures with calcium carbonate content from 20 to 60% was equal to or greater than that of pure microcrystalline cellulose. After lubrication with 2% MS the compactibility decreased, only the mixture with the maximal tablet tensile strength attained the tensile strength of pure microcrystalline cellulose. The presence of the binder, the lubricant and higher compaction pressures allow the accommodation of higher calcium carbonate proportions in the mixtures, at the maximal tablet tensile strength of the series. The lubricant decreases in a greater extent the compactibility of mixtures with a continuous phase of MC/PVP than that of CC/PVP. This is attributed to the plastic behavior of the MC/PVP continuous phase compared to a calcium carbonate continuous phase able to disrupt the Povidone and the possible lubricant coatings allowing a stronger interparticle interaction.

Learning about migration decisions from the migrants: Using complementary datasets to model intra-regional migrations in Spain

We investigate the determinants of the remarkable increase in intra-regional migrations since the 1980's in Spain, using a large administrative micro dataset on migrants. Conditional migration probabilities are identified by comparing the migrants' joint distribution of characteristics to the corresponding distribution from the Spanish Labour Force Survey. The proportion of employment in the service industry, unemployment, house prices and education, all have an important positive effect on the individual probabilities of intra-regional migration.