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International audience; Peer networks can positively affect individual careers and the scientific enterprise as a whole. People's willingness to contribute to such networks is poorly understood. In an email experiment, we investigated how framing the future research environment affects people's willingness to contribute to an emerging academic network. In spite of relatively large treatment effects, we do not find statistically significant effects of pessimistic or optimistic messaging on the willingness to contribute. We discuss limitations of the small sample size and the future research potential of network nudges.

The aim of this study was to devise a method for computing a composite indicator that measures the regional degree of exposure to external knowledge sources. On the basis of this indicator, we propose a typology of regions according to their potential capacity to access extra-local items of knowledge, which might help them to recombine complementary elements of such an asset to produce a higher number of new ideas. Building on various research streams that have been relatively independent to date, we summarize a non-exhaustive instrumental list of recent studies that motivates our approach and the construction of our complex indicator, which can be used to appraise the extent to which each region is in an optimal position to access external innovative resources.

This paper investigates empirically the determinants of firms' performance in the agri-food sector by using recent survey data for Denmark. Treating sales per employee as a proxy for value added, we estimate several bootstrapped regression models to draw conclusions on the marginal effects of potential performance determinants such as the form and nature of ownership, stage of the food chain and commodity sector, new product development, staff quality, firms' competitive stance, and elements of firms' strategy. To draw robust inferences we apply, besides the ordinary heteroscedasticity-corrected Tobit maximum likelihood estimator, a non-parametric least absolute deviations estimator (LAD/CLAD) based on a quantile regression procedure. The results indicate that we cannot reject the hypothesis of no influence of dominant orientation on value added. Rather, firms' focus on human capital, stage and commodity sector better explains their value addition. We reject the hypothesis that regional networks have no influence on value added. Location in Arhus, emphasis on human capital and the negative influence of outsourcing on value added all provide supporting evidence. We reject the hypothesis of no influence of foreign direct investment (FDI), and moreover propose that FDI has targeted the Danish domestic market as a source of value added.

Unearthing an ideal model to describe the role of defect sites for boosting photocatalytic CO2 reduction is rational and necessary, but it still remains a significant challenge. Herein, oxygen vacancies are introduced on the surface of Bi24 O31 Cl10 photocatalyst (Bi24 O31 Cl10 -OV) for fine-tuning the photocatalytic efficiency. The formation of oxygen vacancies leads to a new donor level near the conduction band minimum, which enables a faster charge transfer and higher carrier density. Moreover, oxygen vacancies can considerably reduce the energy for the formation of COOH* intermediates during CO2 conversion. As a result, the activity of Bi24 O31 Cl10 -OV for selective photoreduction of CO2 to CO is significantly improved, with a CO generation rate of 0.9 μmol h-1 g-1 , which is nearly 4 times higher than that of pristine Bi24 O31 Cl10 . This study reinforces our understanding of defect engineering in Bi-based photocatalysts and underscores the potential importance of implanting oxygen vacancies as an effective strategy for solar energy conversion.

Molecular dynamics (MD) simulations and quantum mechanical/molecular mechanical (QM/MM) calculations were performed on the prereactive enzyme-substrate complex, transition states, intermediates, and product involved in the process of human butyrylcholinesterase (BChE)-catalyzed hydrolysis of (−)-cocaine. The computational results consistently reveal a unique role of the oxyanion hole (consisting of G116, G117, and A199) in BChE-catalyzed hydrolysis of cocaine, compared to acetylcholinesterase (AChE)-catalyzed hydrolysis of acetylcholine. During BChE-catalyzed hydrolysis of cocaine, only G117 has a hydrogen bond with the carbonyl oxygen (O31) of the cocaine benzoyl ester in the prereactive BChE-cocaine complex, and the NH groups of G117 and A199 are hydrogen-bonded with O31 of cocaine in all of the transition states and intermediates. Surprisingly, the NH hydrogen of G116 forms an unexpected hydrogen bond with the carboxyl group of E197 side chain and, therefore, is not available to form a hydrogen bond with O31 of cocaine in the acylation. The NH hydrogen of G116 is only partially available to form a weak hydrogen bond with O31 of cocaine in some structures involved in the deacylation. The change of the estimated hydrogen-bonding energy between the oxyanion hole and O31 of cocaine during the reaction process demonstrates how the protein environment can affect the energy barrier for each step of the BChE-catalyzed hydrolysis of cocaine. These insights concerning the effects of the oxyanion hole on the energy barriers provide valuable clues on how to rationally design BChE mutants with a higher catalytic activity for the hydrolysis of (−)-cocaine. Proteins 2006. © 2005 Wiley-Liss, Inc.

This study examines the effect of the 2010 tax credit reform, which reduced the tax credit rate, on firms' R&D in Taiwan. The empirical results suggested that the tax credit rate reduction has no overall negative effects on firms' R&D expenditure. By contrast, firms were observed to increase their expenditure on R&D. R&D tax credit recipients increased their R&D expenditure more than those who did not use the R&D tax credit. Moreover, we found a considerable difference in the treatment effects of the policy reform on R&D between R&D‐intensive and less R&D‐intensive firms. (JEL H21, H25, O31, O32, O38)

Economic growth theory distinguishes between reproducible and nonreproducible factors of production. In traditional growth models based on factor‐augmenting technical change, perpetual economic growth requires that each essential nonreproducible factor, such as labor, be augmented by a reproducible factor, such as human capital. Recent models of factor‐eliminating technical change deliver perpetual growth by eliminating the nonreproducible factors. Heretofore, the literature has kept factor augmentation and factor elimination separate. We analyze a model with both. The model generalizes the traditional factor augmentation approach by relaxing the usual restriction that factor elimination is absent. We obtain the striking result that factor‐augmenting technical change is a misspecification when factor‐eliminating technical change is present. The result raises several questions about technical change and endogenous growth. (JEL O41, O31, O33)

To understand the drivers of product innovation at the firm level, I compare the effects of foreign direct investment (FDI) and exporting on product innovation using a rich firm-level database of manufacturing and industrial enterprises. The article focuses on product innovation, as it is vital to economic development. Estimates from linear regressions and propensity score matching tests show that learning-by-exporting is a stronger predictor of product innovation. Firms that receive foreign investment also tend to engage in more product innovation, but not at the same level as the firms that export. Additional tests confirm that as they start and stop exporting, firms change their patterns of investment in the drivers of product innovation—fixed capital and research. (JEL D22, F14, F23, L25, O31)

We examine the Nash equilibria of a game where two national governments set patent breadth strategically. Broader patents make R&D more attractive, but the effect on static efficiency is nonmonotonic. In a North–South model, where only the North can innovate, harmonization of patent breadth lowers welfare relative to the Nash equilibrium. When both countries can innovate, harmonization toward narrower patent breadth may raise world welfare. (JEL F02, F13, O3, O31, O32)

This article exploits changes in the distribution of immigrants across 20 Organization for Economic Co-operation and Development countries from 1960 to 2005 in order to assess their contribution to income of destination countries. The non-random sorting of immigrants across countries is addressed by using an instrumental variable strategy. The instrument is built by estimating a bilateral migration model incorporating exogenous origin country determinants of migration. Aggregate results reveal that immigrants have a positive effect on income that works primarily through total factor productivity (TFP). We further construct a novel dataset from censuses and labor force surveys to explore the information on the age of immigrants. Contrasting income effects are found across age groups: a higher share of immigrants among the youth has a negative impact on aggregate income, while a higher share of immigrants among prime-aged workers has a positive effect. We interpret this disparity as short-term versus medium-term effects. Adjustments over time involve changes in TFP but also in the human capital of the native-born. (JEL F22, J24, J31, O31)

Where the social planner, threatened by final producers and walled-in by innovators, releases the representative consumer from the pillory, hires two anonymous referees, and convinces the Economics Minister that final firms' purchases of monopolistically produced intermediate inputs should be taxed, not subsidized, as long as output growth does not exhibit scale effects. This normative prescription hinges on an often neglected reallocation mechanism generated by the linear accumulation laws that eliminate scale effects in most endogenous growth models. (JEL O41, O31)

Contributions from the decision-making literature concerning biases and heuristics (i.e., anchoring, framing, confi rmatory and availability biases, overconfi dence, and representativeness) and from the Affect Infusion Model (Forgas, 1995) are integrated into Rogers’s (2003) conceptualization of the stages of innovation adoption and diffusion. Specifi c propositions based on the decision-making and affect literatures are made in relation to each stage of the innovation process (knowledge of innovation, persuasion, decision, implementation, and confi rmation) to better understand the likelihood of a manager making an informed and appropriate decision concerning the adoption and implementation of best practices. Copyright © 2010 ASAC. Published by John Wiley & Sons, Ltd. JEL Classifi cation: O31

We experimentally investigate competition in innovation in a patent race scenario. Pairs of subjects compete as seller firms on a duopoly market, engaging in risky search investments. Successful innovation is rewarded through temporary monopoly rents. Throughout the interaction, subjects receive feedback on own and other’s search success and profit margin. Partitioning subjects into subgroups of investor types reveals that the majority of subjects condition investments on the degree of competition as measured by sales shares, while for others no correlation is ascertained. Heterogeneity in individual risk attitudes and diering experiences with related search tasks may explain this finding. (JEL: D81, L11, O31)

This article argues that collaboration has been a key piston in the engine that is driving economic growth in the new millennium. Innovation in information technology, institutions, and strategic reorientation of technological change has opened opportunity, and competition has put strong imperatives in play for collaborative innovation. First, these imperatives have forced a reorientation of private enterprise from push to pull systems. Second, they have catalyzed a strategic unbundling of integrated firms to create specialized enterprises with enhanced productivity and flexibility, though with increased demand for virtual integration through less formal relationships to establish and manage collaboration. This article presents the hypothesis that these changes induced a fundamentally new dynamic in innovation processes that we label as collaborative pull innovation. This new form of innovation encompasses and directs product, process, and organizational innovation toward fulfilling consumer demand. To examine this hypothesis, the nature of private-sector innovation is assessed within the context of the food sector. This sector is of special interest due to important roles played by small- to medium-sized enterprises. [JEL classification: L11, O31] [EconLit citations: L140, L200, O310]. r 2008 Wiley Periodicals, Inc.

Single crystals of all polar polymorphs, α-Pb2Ba4Zn4B14 O31 (α-PBZB, space group P1, Z = 1), β-PBZB (space group Cc, Z = 4), and γ-PBZB (space group P32, Z = 3) are obtained from high temperature solutions of PbO, BaCO3, ZnO, and H3BO3 in molar ratios of 30:12:23:65 (α), 30:15:20:65 (β), and 10:25:20:65 (γ) (Pt crucible, 850 °C, 10 h; cooling to 500 °C at a rate of 5 °C/h).

Colorless Na10K22 [Zr24O22(OH)10(H2O)2 (W2O10H)2 (GeW9O34)4(GeW8 O31)2]·85H2O crystals are hydrothermally synthesized from a mixture of ZrOCl2, K8Na2[A-α-GeW9O34], and Na2CO3 in a sodium acetate buffer (pH 4.8, autoclave, 200 °C, 3 d; 45% yield).

This article assesses the usefulness of transaction cost economics when we view economic organizations, such as firms as complex adaptive systems. Modern complexity science is a radically different in orientation to neoclassical economics, which deals with decision making in contexts that are presumed to be simple and, therefore, disconnected from complex reality. However transaction cost economics can be related to aspects of modern complexity science: bounded rationality, opportunism, and asset specificity are all associated with behavioral complexity. Furthermore, the emphasis of transaction cost economics on hierarchy and organizational rather than technological considerations is also consistent with complexity science. Drawing on literature in psychological economics, this article synthesizes transaction cost economics with aspects of complexity science in a manner that offers a new research agenda, not only in the context of the organization of production but in economics generally. Such theoretical developments are vital if policy makers are to have at their disposable analytical perspectives that are coherent and applicable in complex historical settings. (JEL A12, A13, D23, L14, L22, O31, Z13).

O31 Multicentre report of the effect of caesarean section on adherence to antiretroviral therapy in a resource-constrained setting R. Akuse, J. Akuse, N. Okeji, J. Adze. Ahmadu Bello University Teaching Hospital, Shika, Zaria, Nigeria, Sefa Specialist Hospital, 5 College Road, P. O. Box 3626, Kaduna, Nigeria, Nigeria Armed Forces Reference Hospital, Kaduna, Nigeria, Barau Dikko Specialist Hospital, Kaduna, Nigeria

O31 Multicentre report of the effect of caesarean section on adherence to antiretroviral therapy in a resource-constrained setting R. Akuse, J. Akuse, N. Okeji, J. Adze. Ahmadu Bello University Teaching Hospital, Shika, Zaria, Nigeria, Sefa Specialist Hospital, 5 College Road, P. O. Box 3626, Kaduna, Nigeria, Nigeria Armed Forces Reference Hospital, Kaduna, Nigeria, Barau Dikko Specialist Hospital, Kaduna, Nigeria

SUMMARY Bean (Phaseolus vulgaris L. CV. pinto) plants were grown in pots in open-top chambers in the field and exposed to three ozone (O3) regimes at a rural site in northwestern New York state: (1) charcoal-filtered air with O3 concentrations during the day of about 40–50% ambient (CF), (2) charcoal-filtered air with O3 added to attain approximately ambient concentrations in real time (1 ×), and (3) charcoal-filtered air with O3 added to attain approximately twice ambient concentrations in real time (2×). Unifoliate leaf blade relative growth rate (RGR) and specific dark respiration rate were measured on 214 plants 12- to 17-d-old. For a given plant age, RGR was significantly reduced by increasing O3 dose, and for a given RGR, specific respiration rate was significantly increased. When the specific respiration rate was mathematically partitioned into growth and maintenance components, it was found that the growth coefficient was unaffected by O3 but the maintenance coefficient was significantly increased by increasing O3 dose: 7.3% between the CF and 1×treatments, and 25% between the 1×and 2×treatments. These results corroborate earlier findings with plants grown in high light conditions in chambers and exposed to 10 or 90 nl O31−1, and suggest that ambient levels of O3 inhibit plant growth in part by diverting respiratory substrate from growth to maintenance and repair processes.