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The Thurstonian item response model (Thurstonian IRT model) allows deriving normative trait estimates from multidimensional forced-choice (MFC) data. In the MFC format, persons must rank-order items that measure different attributes according to how well the items describe them. This study evaluated the normativity of Thurstonian IRT trait estimates both in a simulation and empirically. The simulation investigated normativity and compared Thurstonian IRT trait estimates to those using classical partially ipsative scoring, from dichotomous true-false (TF) data and rating scale data. The results showed that, with blocks of opposite keyed items, Thurstonian IRT trait estimates were normative in contrast to classical partially ipsative estimates. Unbalanced numbers of items per trait, few opposite keyed items, traits correlated positively or assessing fewer traits did not decrease measurement precision markedly. Measurement precision was lower than that of rating scale data. The empirical study investigated whether relative MFC responses provide a better differentiation of behaviors within persons than absolute TF responses. However, criterion validity was equal and construct validity (with constructs measured by rating scales) lower in MFC. Thus, Thurstonian IRT modeling of MFC data overcomes the drawbacks of classical scoring, but gains in validity may depend on eliminating common method biases from the comparison. [ABSTRACT FROM AUTHOR]

In this study we investigate in how far firms in special economic zones (SEZs) have the potential to generate indirect benefits and knowledge spill-overs in the local economy through the creation of backward linkages with local suppliers. For this purpose, we map the linkages between SEZ firms and suppliers in the host economy in seven SEZs around the world, namely in Colombia, Ethiopia, Malaysia, Nigeria, Rwanda, South Africa and Vietnam, based on 103 interviews with SEZ firm managers. We furthermore analyse the challenges in the formation of these linkages. Overall, our findings suggest that, contrary to the objective of many of the zones, backward linkages between firms within SEZs as well as with firms outside the SEZs remain rather limited for the SEZs analysed. Firms primarily purchase services and minor inputs, such as packaging materials, from within or outside the SEZ. The sourcing of key inputs, however, is a major challenge due to a lack of local availability, high local prices and quality concerns. The majority of SEZ firms imports large parts of their inputs from abroad. This is true across a variety of sectors analysed, including garment, high-tech industries and services. [ABSTRACT FROM AUTHOR]

The multidimensional forced-choice (MFC) format is an alternative to rating scales in which participants rank items according to how well the items describe them. Currently, little is known about how to detect careless responding in MFC data. The aim of this study was to adapt a number of indices used for rating scales to the MFC format and additionally develop several new indices that are unique to the MFC format. We applied these indices to a data set from an online survey (N = 1,169) that included a series of personality questionnaires in the MFC format. The correlations among the careless responding indices were somewhat lower than those published for rating scales. Results from a latent profile analysis suggested that the majority of the sample (about 76–84%) did not respond carelessly, although the ones who did were characterized by different levels of careless responding. In a simulation study, we simulated different careless responding patterns and varied the overall proportion of carelessness in the samples. With one exception, the indices worked as intended conceptually. Taken together, the results suggest that careless responding also plays an important role in the MFC format. Recommendations on how it can be addressed are discussed. [ABSTRACT FROM AUTHOR]

A common concern with self-reports of personality traits in selection contexts is faking. The multidimensional forced-choice (MFC) format has been proposed as an alternative to rating scales (RS) that could prevent faking. The goal of this study was to compare the susceptibility of the MFC format and the RS format to faking in a simulated high-stakes setting when using normative scoring for both formats. Participants were randomly assigned to 3 groups (total N = 1,867) and filled out the Big Five Triplets once under an honest instruction and once under a fake-good instruction. Latent mean differences between the honest and fake-good administrations indicated that the Big Five domains were faked in the expected direction. Faking effects for all traits were larger for RS compared with MFC. Faking effects were also larger for the MFC version with mixed triplets compared with the MFC version with triplets that were fully matched regarding their social desirability. The MFC format does not prevent faking completely, but it reduces faking substantially. Faking can be further reduced in the MFC format by matching the items presented in a block regarding their social desirability. (PsycInfo Database Record (c) 2021 APA, all rights reserved). [ABSTRACT FROM AUTHOR]

The multidimensional forced-choice (MFC) format has been proposed as an alternative to the rating scale (RS) response format. However, it is unclear how changing the response format may affect the response process and test motivation of participants. In Study 1, we investigated the MFC response process using the think-aloud technique. In Study 2, we compared test motivation between the RS format and different versions of the MFC format (presenting 2, 3, 4, and 5 items simultaneously). The response process to MFC item blocks was similar to the RS response process but involved an additional step of weighing the items within a block against each other. The RS and MFC response format groups did not differ in their test motivation. Thus, from the test taker's perspective, the MFC format is somewhat more demanding to respond to, but this does not appear to decrease test motivation. [ABSTRACT FROM AUTHOR]

The multidimensional forced-choice (MFC) format has been proposed as an alternative to rating scales (RS) that may be less susceptible to response biases. The goal of this study was to compare the validity of trait estimates from the MFC and the RS format when using normative scoring for both formats. We focused on construct validity and criterion-related validity. In addition, we investigated test-retest reliability over a period of six months. Participants were randomly assigned the MFC (N = 593) or the RS (N = 622) version of the Big Five Triplets. In addition to self-ratings on the Big Five Triplets and other personality questionnaires and criteria, we also obtained other-ratings (N = 770) for the Big Five Triplets. The Big Five in the Big Five Triplets corresponded well with the Big Five in the Big Five Inventory except for agreeableness in the MFC version. The majority of the construct validity coefficients differed between the MFC and the RS version, whereas criterion-related validities were very similar. The self- and other-rated Big Five Triplets showed higher correlations in the MFC format than in the RS format. The reliability of trait estimates on the Big Five and test-retest reliabilities were lower for MFC compared to RS. For the MFC format to be able to replace the RS format, more research on how to obtain ideal constellations of items that are matched in their desirability is needed. (PsycINFO Database Record (c) 2020 APA, all rights reserved). [ABSTRACT FROM AUTHOR]

Despite a massive recent proliferation of special economic zones (SEZs), there is virtually no quantitative research on what drives their dynamism. The aim of this article is to address this gap and analyze the factors influencing SEZ performance—proxied by economic growth—in emerging countries. The article relies on two novel data sets, using nightlights data to proxy for SEZ performance, and containing a wide range of SEZ policy variables and characteristics across a large number of countries. The main results of the analysis indicate that (1) zone growth is difficult to sustain over time; (2) trying to upgrade the technological component or value added of the economy through SEZ policies is often challenging; and (3) zone size matters: larger zones have an advantage in terms of growth potential. Furthermore, country context significantly determines SEZ performance. Firms look for low-cost locations but in close proximity to large cities. Proximity to large markets as well as preexisting industrialization also increase SEZ performance. In contrast, incentives and other program-specific variables are highly context specific and not structurally correlated with SEZ performance. [ABSTRACT FROM AUTHOR]

The paper investigates (1) the evolution of urban concentration from 1985 to 2010 in 68 countries around the world and (2) the extent to which the degree of urban concentration affects national economic growth. It aims to overcome the limitations of existing empirical literature by building a new urban population dataset that allows the construction of a set of Herfindahl-Hirschman-Indices which capture a country’s urban structure in a more nuanced way than the indicators used hitherto. We find that, contrary to the general perception, urban concentration levels have on average decreased or remained stable (depending on indicator). However, these averages camouflage diverging trends across countries. The results of the econometric analysis suggest that there is no uniform relationship between urban concentration and economic growth. Urban concentration is beneficial for economic growth in high-income countries, while this effect does not hold for developing countries. The results differ from previous analyses that generally underscore the benefits of urban concentration at low levels of economic development. The results are robust to accounting for reverse causality through IV analysis, using exogenous geographic factors as instruments. [ABSTRACT FROM AUTHOR]

Abstract: Policy makers and academics frequently emphasize a positive link between city size and economic growth. The empirical literature on the relationship, however, is scarce and uses rough indicators for the size of a country's cities, while ignoring factors that are increasingly considered to shape this relationship. In this paper, we employ a panel of 113 countries between 1980 and 2010 to explore whether 1) there are certain city sizes that are growth enhancing and 2) how additional factors highlighted in the literature impact the city size/growth relationship. The results suggest a nonlinear relationship which is dependent on the country's size. In contrast to the prevailing view that large cities are growth‐inducing, for a majority of countries relatively small cities of up to 3 million inhabitants are more conducive to economic growth. A large share of the urban population in cities of more than 10 million inhabitants is only growth promoting in countries with an urban population of 28.5 million and more. In addition, the relationship is highly context‐dependent: a high share of industries that benefit from agglomeration economies, a well‐developed urban infrastructure, and an adequate level of governance effectiveness allow countries to take advantage of agglomeration benefits from larger cities. [ABSTRACT FROM AUTHOR]

Abstract: Morphine biosynthesis was genetically engineered in an industrial elite line of the opium poppy (Papaver somniferum L.), to modify the production of alkaloids in plants. The cytochrome P-450-dependent monooxygenase (S)-N-methylcoclaurine 3′-hydroxylase (CYP80B3) lies on the pathway to the benzylisoquinoline alkaloid branch point intermediate (S)-reticuline. Overexpression of cyp80b3 cDNA resulted in an up to 450% increase in the amount of total alkaloid in latex. This increase occurred either without changing the ratio of the individual alkaloids, or together with an overall increase in the ratio of morphine. Correspondingly, antisense-cyp80b3 cDNA expressed in opium poppy caused a reduction of total alkaloid in latex up to 84%, suggesting that the observed phenotypes were dependent on the presence of the transgene. This study found compelling evidence, that cyp80b3 is a key regulation step in morphine biosynthesis and provides practical means to genetically engineer valuable secondary metabolites in this important medicinal plant. [Copyright &y& Elsevier]

Summary: In cell suspension cultures of the meadow rueThalictrum tuberosum, biosynthesis of the anti-microbial alkaloid berberine can be induced by addition of methyl jasmonate to the culture medium. The activities of the four methyltransferases involved in the formation of berberine from L-tyrosine are increased in response to elicitor addition. Partial clones generated by RT–PCR with methyltransferase-specific primers were used as hybridization probes to isolate four cDNAs encodingO-methyltransferases from a cDNA library prepared from poly(A)+ RNA isolated from methyl jasmonate-induced cell suspension cultures ofT. tuberosum. RNA gel blot hybridization indicated that the transcripts for the methyltransferases accumulated in response to addition of methyl jasmonate to the cell culture medium. The cDNAs were functionally expressed inSpodoptera frugiperdaSf9 cells and were shown to have varying and broad substrate specificities. A difference of a single amino acid residue between two of the enzymes was sufficient to alter the substrate specificity. The four cDNAs were expressed either as four homodimers or as six heterodimers by co-infection with all possible combinations of the four recombinant baculoviruses. These 10 isoforms thus produced displayed distinct substrate specificities and in some cases co-infection with two different recombinant baculoviruses led to theO-methylation of new substrates. The substrates that wereO-methylated varied in structural complexity from simple catechols to phenylpropanoids, tetrahydrobenzylisoquinoline, protoberberine and tetrahydrophenethylisoquinoline alkaloids, suggesting that some biosynthetic enzymes may be common to both phenylpropanoid and alkaloid anabolism.. [ABSTRACT FROM AUTHOR]

Abstract: Papaver somniferum L. was transformed with an RNAi construct designed to reduce transcript levels of the gene encoding the morphine biosynthetic enzyme, salutaridinol 7-O-acetyltransferase (SalAT). RNA interference of salAT led to accumulation of the intermediate compounds, salutaridine and salutaridinol, in a ratio ranging from 2:1 to 56:1. Along the morphine biosynthetic pathway, salutaridine is stereospecifically reduced by salutaridine reductase (SalR) to salutaridinol, which is subsequently acetylated by SalAT. SalAT transcript was shown by quantitative PCR to be diminished, while salR transcript levels remained unaffected. Yeast two-hybrid and co-immunoprecipitation analyses indicated an interaction between SalR and SalAT, which suggested the occurrence of an enzyme complex and provided an explanation for the unexpected accumulation of salutaridine. Decreased concentrations of thebaine and codeine in latex were also observed, while the morphine levels remained constant compared to concentrations found in untransformed control plants. [Copyright &y& Elsevier]

Only plants of the Papaver genus (poppies) are able to synthesize morphinan alkaloids, and cultivation of P. somniferum, opium poppy, remains critical for the production and supply of morphine, codeine and various semi-synthetic analgesics. Opium poppy was transformed with constitutively expressed cDNA of codeinone reductase ( PsCor1.1), the penultimate step in morphine synthesis. Most transgenic lines showed significant increases in capsule alkaloid content in replicated glasshouse and field trials over 4 years. The morphinan alkaloid contents on a dry weight basis were between 15% and 30% greater than those in control high-yielding genotypes and control non-transgenic segregants. Transgenic leaves had approximately 10-fold greater levels of Cor transcript compared with non-transgenic controls. Two cycles of crossing of the best transgenic line into an elite high-morphine genotype resulted in significant increases in morphine and total alkaloids relative to the elite recurrent parent. No significant changes in alkaloid profiles or quantities were observed in leaf, roots, pollen and seed. [ABSTRACT FROM AUTHOR]