bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effectiveness of protein‐rich pea flour for the control of stored‐product beetles
Authors: Hou Xingwei , Fields Paul 
Published: July 2003

AbstractProtein‐rich pea flour is toxic to many stored‐product insects. We investigated several factors that may affect the efficacy of protein‐rich pea flour: insect species, insect population densities, grain species, temperature, and moisture. Adult Sitophilus oryzae (L.) (Coleoptera: Curculionidae) was more susceptible to protein‐rich pea flour than Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae). Protein‐rich pea flour did not increase the mortality of adult Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). However, it reduced the number of offspring of all three species. The toxicity of protein‐rich pea flour was not reduced after 9 months when stored at −15 °C, or at room temperature as flour or mixed with grain. Its toxicity in wheat increased with higher temperature and at lower grain moisture contents. Protein‐rich pea flour was more toxic in wheat and barley than in maize. This difference among grain species was not due to the kernel size of the grain, as ground wheat or maize with the same particle size still had different LD50s.
Effects of mass releases of Trichogramma brassicae on predatory insects in maize
Authors: Babendreier D. , Rostas M. , Höfte M. C. J. , Kuske S. , Bigler F. 
Published: July 2003

AbstractWe investigated whether mass releases of Trichogramma brassicae against the European corn borer will have detrimental effects on populations of other natural enemies in maize. In a tiered approach, experiments investigated the host acceptance of T. brassicae towards eggs of Chrysoperla carnea, Episyrphus balteatus, Adalia bipunctata, and Coccinella septempunctata under laboratory, caged, and field conditions. The factitious host, Ephestia kuehniella, and in one case also Mamestra brassicae were used as control. Under laboratory conditions, 53% of the T. brassicae females parasitised C. carnea eggs, 70% parasitised E. balteatus eggs, while 91% of the females parasitised E. kuehniella eggs, with T. brassicae emerging from C. carnea, E. balteatus, and E. kuehniella at rates higher than 81%. No parasitoid offspring emerged from eggs of A. bipunctata and C. septempunctata. However, we observed significantly increased mortality on A. bipunctata eggs, compared to the control, and also found young instars of T. brassicae inside A. bipunctata eggs. In a second experiment where the host acceptance behaviour of the parasitoid female was directly observed for 10 min, 10% of T. brassicae females were found to oviposit in eggs of A. bipunctata, but the development of parasitoid offspring failed. No C. septempunctata eggs, 13% of E. balteatus eggs, 23% of C. carnea eggs, 33% of E. kuehniella egg clusters, and 83% of M. brassicae eggs were accepted for oviposition. In the greenhouse under caged conditions, the parasitism rate of C. carnea eggs (7%) and E. balteatus eggs (0.4%) were significantly lower than of E. kuehniella eggs (21 and 27%, respectively). In the final tier, 3.1% of C. carnea eggs were parasitised by T. brassicae under field conditions. This was significantly less than the observed parasitism rate of E. kuehniella egg clusters (64%). From direct observations of the parasitoids’ host acceptance behaviour and the low parasitism rates observed under caged and field conditions, we conclude that detrimental effects of the mass release of T. brassicae on populations of natural enemies in maize are unlikely to occur.
On the Diophantine equation 𝐺_{𝑛}(𝑥)=𝐺_{𝑚}(𝑃(𝑥)): Higher-order recurrences
Authors: Fuchs Clemens , Pethő Attila , Tichy Robert 
Published: July 2003

Let

K

\mathbf {K}

be a field of characteristic

0
0

and let

(

G

n

(
x
)

)

n
=
0

∞

(G_{n}(x))_{n=0}^{\infty }

be a linear recurring sequence of degree

d
d

in

K

[
x
]

\mathbf {K}[x]

defined by the initial terms

G
0

,
…
,

G

d
−
1

∈

K

[
x
]

G_0,\ldots ,G_{d-1}\in \mathbf {K}[x]

and by the difference equation
\[

G

n
+
d

(
x
)
=

A

d
−
1

(
x
)

G

n
+
d
−
1

(
x
)
+
⋯
+

A
0

(
x
)

G

n

(
x
)
,

for

n
≥
0
,

G_{n+d}(x)=A_{d-1}(x)G_{n+d-1}(x)+\cdots +A_0(x)G_{n}(x), \quad \mbox {for} \,\, n\geq 0,

\]
with

A
0

,
…
,

A

d
−
1

∈

K

[
x
]

A_0,\ldots ,A_{d-1}\in \mathbf {K}[x]

. Finally, let

P
(
x
)

P(x)

be an element of

K

[
x
]

\mathbf {K}[x]

. In this paper we are giving fairly general conditions depending only on

G
0

,
…
,

G

d
−
1

,

G_0,\ldots ,G_{d-1},

on

P
P

, and on

A
0

,
…
,

A

d
−
1

A_0,\ldots ,A_{d-1}

under which the Diophantine equation
\[

G

n

(
x
)
=

G

m

(
P
(
x
)
)

G_{n}(x)=G_{m}(P(x))

\]
has only finitely many solutions

(
n
,
m
)
∈

Z

2

,
n
,
m
≥
0

(n,m)\in \mathbb {Z}^{2},n,m\geq 0

. Moreover, we are giving an upper bound for the number of solutions, which depends only on

d
d

. This paper is a continuation of the work of the authors on this equation in the case of second-order linear recurring sequences.
Cytoplasmic N-Terminal Protein Acetylation Is Required for Efficient Photosynthesis in Arabidopsis[W]
Authors: Pesaresi Paolo , Gardner Nora A. , Masiero Simona , Dietzmann Angela , Eichacker Lutz , Wickner Reed , Salamini Francesco , Leister Dario 
Published: August 2003

AbstractThe Arabidopsis atmak3-1 mutant was identified on the basis of a decreased effective quantum yield of photosystem II. In atmak3-1, the synthesis of the plastome-encoded photosystem II core proteins D1 and CP47 is affected, resulting in a decrease in the abundance of thylakoid multiprotein complexes. DNA array–based mRNA analysis indicated that extraplastid functions also are altered. The mutation responsible was localized to AtMAK3, which encodes a homolog of the yeast protein Mak3p. In yeast, Mak3p, together with Mak10p and Mak31p, forms the N-terminal acetyltransferase complex C (NatC). The cytoplasmic AtMAK3 protein can functionally replace Mak3p, Mak10p, and Mak31p in acetylating N termini of endogenous proteins and the L-A virus Gag protein. This result, together with the finding that knockout of the Arabidopsis MAK10 homolog does not result in obvious physiological effects, indicates that AtMAK3 function does not require NatC complex formation, as it does in yeast. We suggest that N-acetylation of certain chloroplast precursor protein(s) is necessary for the efficient accumulation of the mature protein(s) in chloroplasts.
Contrasting Effects of Selection on Sequence Diversity and Linkage Disequilibrium at Two Phytoene Synthase Loci[W]
Authors: Palaisa Kelly A. , Morgante Michele , Williams Mark , Rafalski Antoni 
Published: August 2003

AbstractWe investigated the effects of human selection for yellow endosperm color, representing increased carotenoid content, on two maize genes, the Y1 phytoene synthase and PSY2, a putative second phytoene synthase. Multiple polymorphic sites were identified at Y1 and PSY2 in 75 white and yellow maize inbred lines. Many polymorphic sites showed strong association with the endosperm color phenotype at Y1, but no detectable association was found at PSY2. Nucleotide diversity was equivalent for whites and yellows at PSY2 but was 19-fold less in yellows than in whites at Y1, consistent with the white ancestral state of the gene. The strong sequence haplotype conservation within yellows at Y1 and a significant, negative Tajima's D both verified positive selection for yellow endosperm. We propose that two independent gain-of-function events associated with insertions into the promoter of the Y1 gene and upregulation of expression in endosperm have been incorporated into yellow maize.
The Arabidopsisppi1Mutant Is Specifically Defective in the Expression, Chloroplast Import, and Accumulation of Photosynthetic Proteins[W]
Authors: Kubis Sybille , Baldwin Amy , Patel Ramesh , Razzaq Azam , Dupree Paul , Lilley Kathryn , Kurth Joachim , Leister Dario , Jarvis Paul 
Published: August 2003

AbstractThe import of nucleus-encoded proteins into chloroplasts is mediated by translocon complexes in the envelope membranes. A component of the translocon in the outer envelope membrane, Toc34, is encoded in Arabidopsis by two homologous genes, atTOC33 and atTOC34. Whereas atTOC34 displays relatively uniform expression throughout development, atTOC33 is strongly upregulated in rapidly growing, photosynthetic tissues. To understand the reason for the existence of these two related genes, we characterized the atTOC33 knockout mutant ppi1. Immunoblotting and proteomics revealed that components of the photosynthetic apparatus are deficient in ppi1 chloroplasts and that nonphotosynthetic chloroplast proteins are unchanged or enriched slightly. Furthermore, DNA array analysis of 3292 transcripts revealed that photosynthetic genes are moderately, but specifically, downregulated in ppi1. Proteome differences in ppi1 could be correlated with protein import rates: ppi1 chloroplasts imported the ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit and 33-kD oxygen-evolving complex precursors at significantly reduced rates, but the import of a 50S ribosomal subunit precursor was largely unaffected. The ppi1 import defect occurred at the level of preprotein binding, which is consistent with a role for atToc33 during preprotein recognition. The data suggest that atToc33 is involved preferentially in the import of photosynthetic proteins and, by extension, that atToc34 is involved in the import of nonphotosynthetic chloroplast proteins.
The Mitochondrial Genome of Chara vulgaris: Insights into the Mitochondrial DNA Architecture of the Last Common Ancestor of Green Algae and Land Plants[W]
Authors: Turmel Monique , Otis Christian , Lemieux Claude 
Published: August 2003

Abstract
Mitochondrial DNA (mtDNA) has undergone radical changes during the evolution of green plants, yet little is known about the dynamics of mtDNA evolution in this phylum. Land plant mtDNAs differ from the few green algal mtDNAs that have been analyzed to date by their expanded size, long spacers, and diversity of introns. We have determined the mtDNA sequence of Chara vulgaris (Charophyceae), a green alga belonging to the charophycean order (Charales) that is thought to be the most closely related alga to land plants. This 67,737-bp mtDNA sequence, displaying 68 conserved genes and 27 introns, was compared with those of three angiosperms, the bryophyte Marchantia polymorpha, the charophycean alga Chaetosphaeridium globosum (Coleochaetales), and the green alga Mesostigma viride. Despite important differences in size and intron composition, Chara mtDNA strikingly resembles Marchantia mtDNA; for instance, all except 9 of 68 conserved genes lie within blocks of colinear sequences. Overall, our genome comparisons and phylogenetic analyses provide unequivocal support for a sister-group relationship between the Charales and the land plants. Only four introns in land plant mtDNAs appear to have been inherited vertically from a charalean algar ancestor. We infer that the common ancestor of green algae and land plants harbored a tightly packed, gene-rich, and relatively intron-poor mitochondrial genome. The group II introns in this ancestral genome appear to have spread to new mtDNA sites during the evolution of bryophytes and charalean green algae, accounting for part of the intron diversity found in Chara and land plant mitochondria.
An Arabidopsis Mutant Resistant to Thaxtomin A, a Cellulose Synthesis Inhibitor fromStreptomycesSpecies[W]
Authors: Scheible Wolf-Rüdiger , Fry Barbara , Kochevenko Andrej , Schindelasch Dana , Zimmerli Laurent , Somerville Shauna , Loria Rosemary , Somerville Chris R. 
Published: August 2003

AbstractThaxtomin A is a phytotoxin produced by Streptomyces scabies and other Streptomyces species, the causative agents of common scab disease in potato and other taproot crops. At nanomolar concentrations, thaxtomin causes dramatic cell swelling, reduced seedling growth, and inhibition of cellulose synthesis in Arabidopsis. We identified a mutant of Arabidopsis, designated txr1, that exhibits increased resistance to thaxtomin as a result of a decrease in the rate of toxin uptake. The TXR1 gene was identified by map-based cloning and found to encode a novel, small protein with no apparent motifs or organelle-targeting signals. The protein, which has homologs in all fully sequenced eukaryotic genomes, is expressed in all tissues and during all developmental stages analyzed. Microarray transcript profiling of some 14,300 genes revealed two stomatin-like genes that were expressed differentially in the txr1 mutant and the wild type. We propose that TXR1 is a regulator of a transport mechanism.
Dry Holes in Economic Research
Authors: Laband David N. , Tollison Robert D. 
Published: July 2003

SummaryBetween 1974 and 1996, there was a substantial increase in the emphasis on academic research in universities located in the United States and elsewhere throughout the world. This increased emphasis was, and continues to be, reflected in a variety of increased incentives for faculty to produce research, including higher salaries, reduced teaching loads, increased money for travel, on so on. Yet, as we report in this paper, during this time period the rate of uncitedness of economics papers remained constant (at 26 percent). Clearly, universities and taxpayers/supporters of universities are obtaining no enhancement of research output (in terms of citations) from the increased subsidy to faculty research. We discuss the implications of this result for the publication and organization of economic research. In particular, we discuss the fact that resources devoted to up‐front screening of papers by authors and journals have risen substantially over this period, but to no avail with respect to reducing the incidence of dry holes.
Reputation and Relevance of Economics Journals
Authors: Bräuninger Michael , Haucap Justus 
Published: July 2003

SummaryWe analyse the interrelationship between economics journals' relevance and reputation. While reputation and relevance positively affect each other, relevance has a much stronger impact on reputation than reputation on relevance. Citation frequency is a key determinant for both journal reputation and relevance, but effects on journal reputation are nearly twice as strong. Specialised journals are, ceteris paribus, considered less relevant and, therefore, also less reputed, even though specialisation has a positive direct effect on reputation. German‐speaking economists find German journals more relevant, but at the same time also less reputed than foreign journals. Age and volume effects are also analysed.
Access as a Motivational Device: Implications for Human Resource Management
Authors: Arocena Pablo , Villanueva Mikel 
Published: July 2003

SummaryIn this paper we analyse the provision of incentives at work on the basis that the employment relationship is not solely an exchange of work for money. Particularly, in addition to a salary, a job also gives access to a working experience, which determines the potential for employee's human capital acquisition and for his social and professional recognition. Accordingly, we argue that the level of access defines the employee's opportunities for satisfying his self‐actualisation and achievement needs. Further, given that the firm has the ability to regulate access by way of a number of organisational decisions, access becomes a powerful mechanism to activate the worker's internal motivation. In this respect, the main purpose of this paper is to study the effect of access and intrinsic motivation on employee's performance and job design. To that effect, we analyse the economic consequences of our arguments on access through a model of agency enriched with a number of psychological and organisational considerations. Our results and conclusions are consistent with much of the interdisciplinary research on the subject, as well as with the evidence emerging from the real business practice. They also provide a number of practical implications for personnel policies. First, in order to activate the individual's internal motivation, the job must reach a minimum value. Second, the positive effect of the employee's intrinsic motivation on effort decreases with the magnitude of monetary incentives. Third, the efficiency gains generated by the extension of job access increase with the employee's level of perceived risk. Finally, the costs of selection are a consequence of granting access.
Corruption, Productivity and Socialism
Authors: Wyatt Geoffrey 
Published: July 2003

SummaryThe level of productivity is correlated across countries with measures of (lack of) corruption, but this appears to be due to a common association of these variables with measures of civil infrastructure, here measured by a combination of governance indexes labelled ‘rule of law’ and ‘government effectiveness’. New instruments based on the size‐ and spatial‐distributions of cities within the countries of the world were constructed in order to explore the causal relationships between civil infrastructure and productivity. Civil infrastructure accounts for a substantial fraction of the global variation in output per worker across countries. Within this empirical pattern there is a systematic deviation associated with the current and former socialist states, which have both lower productivity and inferior civil infrastructure than would be predicted for otherwise similar non‐socialist states. However, for a given level of the index of civil infrastructure these states are also shown to have ahigherlevel of productivity than otherwise similar non‐socialist states. The unconditionally low productivity of socialist states is attributed entirely to the indirectly deleterious effects that socialism had on civil infrastructure, which more than offset its directly positive effect on output.
Choice Behaviour: Looking for Remedy to Some Central Logical Problems in Rational Action
Authors: Kaisla Jukka 
Published: July 2003

SummaryThe purpose of this paper is to examine connections between rationality and rule following, and to propose that a distinction between consequential and procedural interests can help us in explaining choice behaviour in general. The limitations of Rational Choice theory have become increasingly established in economics. An alternative behavioural theory, Rule‐Individualism, is assessed in the paper, with the conclusion that it fails in its attempt to provide a genuinely different perspective compared to Rational Choice theory. Hayek's theory of mind works as a bridge, connecting rule following, as a behavioural pattern, with contextual discretion. The central message in Hayek's book in the field of psychology, The Sensory Order, is that all types of action are fundamentally based on our ability to discern recurrent patterns. That is, all action is essentially rule‐based. A question then arises about a potential explanation to the distinction between rule following and discretion at the observable level of individual action. Rational Choice theory is silent about this, and Rule‐Individualism, it will be explained, is inherently inconsistent when dealing with the logic of rule following. This paper aims at offering a potential explanation which is not inconsistent or tautological.
Larger brain and white matter volumes in children with developmental language disorder
Authors: Herbert Martha R. , Ziegler David A. , Makris Nikos , Bakardjiev Anna , Hodgson James , Adrien Kristen T. , Kennedy David N. , Filipek Pauline A. , Caviness Verne S. 
Published: July 2003

AbstractDevelopmental language disorder (DLD) is predominantly a language disorder, but children with DLD also manifest non‐language impairments, and neuroanatomical abnormalities have been found in multiple areas of the brain, not all language‐associated. We therefore performed a whole brain general segmentation analysis of all major brain regions on MRI scans of 24 DLD subjects (16M, 8F) and 30 controls (15M, 15F), ages 5.7 to 11.3 years. Children with DLD showed increased total brain volume, driven predominantly by a substantial increase in the volume of cerebral white matter. Cerebral cortex and caudate were relatively but not absolutely smaller in DLD. These findings are discussed in relation to issues of specificity vs. generality as they arise in debates about (1) modular vs. general processing deficits and connectionist modeling in DLD, (2) language‐specific vs. pervasive, non‐specific deficits in DLD and (3) specificity of the disorder vs. overlap with other disorders, notably autism.
Connectionism and dynamic systems: are they really different?
Authors: Thelen Esther , Bates Elizabeth 
Published: July 2003

AbstractWe propose that connectionism and dynamic systems theory are strong contenders for a general theory of development that holds true whatever the content domain. We illustrate, through our own career narratives, the origins of these theories in motor and language development. We situate connectionism and dynamic systems among other classic and contemporary theories and conclude that, although there are meaningful differences, these differences pale in relation to the shared assumptions about the fundamental processes and mechanisms of change.
Bridging the representational gap in the dynamic systems approach to development
Authors: Spencer John P. , Schöner Gregor 
Published: July 2003

AbstractWe describe the relationship between the dynamic systems approach to development and a recent approach to the dynamics of representational states – the dynamic field approach. Both approaches share an emphasis on the concepts of stability (attractor states), instability (especially bifurcations), soft‐assembly and flexibility. But the dynamic field approach adds the concept of ‘activation’ to capture the strength with which behaviorally relevant information is specified. By explicitly linking these dynamic systems approaches, we allow for more direct comparisons between dynamic systems theory and connectionism. We note three current differences between these two approaches to development: (1) the notion of stability is central to how representational states are conceptualized in the dynamic field approach; (2) the dynamic field approach is more directly concerned with the sensorimotor origins of cognition; and (3) the dynamic approach is less advanced with regard to learning. We conclude that proponents of the two approaches can learn from the respective strengths of each approach. We suspect these differences will largely disappear in the next 20 years.
Connectionist models of development
Authors: Munakata Yuko , McClelland James L. 
Published: July 2003

AbstractHow have connectionist models informed the study of development? This paper considers three contributions from specific models. First, connectionist models have proven useful for exploring nonlinear dynamics and emergent properties, and their role in nonlinear developmental trajectories, critical periods and developmental disorders. Second, connectionist models have informed the study of the representations that lead to behavioral dissociations. Third, connectionist models have provided insight into neural mechanisms, and why different brain regions are specialized for different functions. Connectionist and dynamic systems approaches to development have differed, with connectionist approaches focused on learning processes and representations in cognitive tasks, and dynamic systems approaches focused on mathematical characterizations of physical elements of the system and their interactions with the environment. The two approaches also share much in common, such as their emphasis on continuous, nonlinear processes and their broad application to a range of behaviors.