Miracle-dz/UniFAR-FTUs huggingface dataset:
Physiological integration ameliorates effects of serpentine soils in the clonal herb Fragaria vesca

Small-scale heterogeneity in soil characteristics and the facility of clonal systems to spread may lead to situations where parent ramets in favourable microhabitats are connected to offspring in stressful conditions. Clonal plants are physiologically integrated if connections among ramets allow transport of resources. Thus, ramets in favourable habitats may provide support to developing or stressed ramets. We examined effects of integration in Fragaria vesca growing in patches of contrasting quality (potting compost vs serpentine soil). Serpentine soil was used to create unfavourable growing conditions. We assessed whether survival, biomass and photosynthetic efficiency (estimated by fluorescence and reflectance) of parents and offspring were affected by integration and soil quality. Integration increased photochemical efficiencies of parents but more consistently in parents with offspring growing in serpentine soils. We suggest that the assimilate demand from offspring enhanced the photosynthetic efficiency of parents by a mechanism of feedback regulation. This result extends the concept of physiological integration in clonal plants to include photochemical responses. Connected parents also showed significantly higher biomass than disconnected parents. In our system, integration did not entail costs for the whole clone in terms of biomass. Integration also improves the survival, growth and photochemical efficiency of developing ramets, suggesting that integration represents a mechanism for increasing survival in stressful habitats, as the serpentine soils.
Secondary woody vegetation patterns in New Zealand’s South Island dryland zone

Abstract Can New Zealand’s indigenous dryland ecosystems be rehabilitated by facilitating inherent successional tendencies to enhance development of indigenous-dominated and often woody communities in the long term? Here, we describe the geographic distribution of woody communities of New Zealand’s South Island drylands to generate hypotheses about successional trajectories to future vegetation states. Presences and absences of woody species in 3880 vegetation plots collated from past surveys were used to predict species potential distributions across drylands. Separate models and spatial predictions were built for each of four classes of woody richness, which were used as surrogates for successional stages. Woody species richness increased significantly from grassland to shrubland and from shrubland to forest cover, and trends in species traits also suggest richness class was related with successional stage. Indigenous woody species outnumbered exotic species in all richness classes. Assuming richness classes represent temporal progressions, our results suggest relatively homogeneous early-successional woody associations succeed to a divergent array of woody associations in different environments. Growth forms of species in our predicted associations suggest transitions from grassland to tall, tree-rich forests in northern and coastal drylands, and to liane-rich open or lightcanopied shrubland, woodland, or low forest in more severe inland environments. These putative communities are novel in species composition but physiognomically broadly similar to pre-settlement analogues. Especially in severe inland environments, unassisted transitions from grassland to indigenousdominated late-successional woody communities may depend on the exclusion of tall exotic trees, Scotch broom, and gorse in early succession.
THE FLORAL AND EXTRA‐FLORAL NECTARIES OF PASSIFLORA. II. THE EXTRA‐FLORAL NECTARY

Floral nectary development and nectar secretion in three species of Passiflora were investigated with light and electron microscopy. The nectary ring results from the activity of an intercalary meristem. Increased starch deposition in the amyloplasts of the secretory cells parallels maturation of the nectary phloem. Large membrane-bound protein bodies are observed consistently in phloem parenchyma cells, but their function is presently unknown. The stored starch serves as the main source of nectar sugars at anthesis. Plastid envelope integrity is maintained during starch degradation, and there is no evidence of participation of endoplasmic reticulum or Golgi in the secretion of pre-nectar. It is concluded that in these starchy nectaries granulocrine secretion, commonly reported for floral nectaries, does not occur. SINCE THE LATTER PART of the nineteenth century considerable descriptive work has appeared in the literature concerning nectary anatomy (Behrens, 1879; Bohmker, 1917; Fahn, 1952; An6ibor, 1969; Elias and Gelband, 1976). The earliest investigations centered largely on floral nectaries, and it was observed with light microscopy that starch was often a conspicuous component of the secretory cells at the time of flowering (Bohmker, 1917; Ball,
TRADING HEAT AND FOOD FOR SAFETY: COSTS OF PREDATOR AVOIDANCE IN A LIZARD

I examined the long-term consequences of a trade-off between predation risk and resource acquisition for the garden skink (Lampropholis guichenoti) by rearing hatchlings to maturity in outdoor enclosures covered with snake predator scent (mimicking high predator densities) or control scent (mimicking low predator densities). Open areas provided optimal foraging and basking sites but were covered with scent, whereas retreat sites provided suboptimal foraging and basking opportunities and were not scented. During the initial six months of the experiment, lizards reared in enclosures covered with scent from a natural predator became active later in the day, showed reduced mobility, and selected “safer” substrate microhabitats than did lizards raised in enclosures covered with control scent. These behavioral shifts reduced opportunities to forage and bask for lizards in the predator-scented enclosures. During the study, however, lizards from predator-scented enclosures became gradually less responsive to snak.
Crop Productivity, Steviol Glycoside Yield, Nutrient Concentration and Uptake of Stevia rebaudiana Bert. under Mediterranean Field Conditions

Stevia rebaudiana Bertoni (Asteraceae Family), characterized by a high content of steviol glycosides (SG) in its leaves, represents an interesting source of non-sucrose and no-calorie sweeteners. Stevia, which is native to Paraguay, is a relatively new crop for the Mediterranean region, where it is grown as an annual or poly-annual crop. In order to assess the crop’s environmental requirements, productive performance and nutrient uptakes, a two-year field experiment was carried out in north-eastern Italy, where the species had never previously been cultivated. The aim was to evaluate the effects of important pre-harvest factors, such as cultivation site, harvest time and their reciprocal interaction, on productivity, leaf SG yield and nutrient requirements. Results showed that the timing of the harvest and the pedo-climatic conditions of the cultivation sites had a significant effect on the main biometric traits, total and leaf dry yield, SG production, macronutrient concentration and uptake.
Possible nutritional and health-related value promotion in orange juice preserved by high-pressure treatment†

Effects of high-pressure treatment on the orange juice carotenoids (β-carotene, α-carotene, zeaxanthin, lutein and β-cryptoxanthin) associated with nutritional (vitamin A) and health-related (radical-scavenging capacity) values were investigated. Various high-pressure treatments (50-350 MPa) combined with different temperatures (30 and 60°C) and times (2.5, 5 and 15 min) of treatment were assayed. The carotenoid content of the orange juice was analysed by HPLC-UV, the vitamin A value was determined as retinol equivalents (RE) and the free radical-scavenging capacity was evaluated using the DPPH (2,2-diphenyl-1,1-picrylhydrazyl) radical model system. A storage study was carried out at refrigeration temperature (4°C). High-pressure treatments at 350MPa produced significant increases of 20-43% in the carotenoid content of fresh orange juice (from 3.99 to 4.78-5.70mg l -1 ). A non-uniform behaviour of high-pressure treatments was detected. An increase in time (beyond 5min) or temperature (above 30°C) of treatment did not improve the amount of carotenoids extracted. Owing to better extraction of carotenoids, an increase in vitamin A value from 164 to 238 RE l -1 (45%) was achieved with the 350 MPa/30°C/5 min treatment. No correlation was found between the increase in carotenoid amount extracted and the free radical-scavenging activity. Dans cette etude, les effets d'un traitement par haute pression sur la composition en carotenoides, la teneur en vitamine A et la capacite de captation de radicaux libres de jus d'orange d'Espagne fraichement presses sont examines. Les changements dans ces parametres pendant un entreposage refrigere a 4°C sont aussi evalues. Un traitement de 350MPa/30°C/5mn permet d'obtenir la concentration en carotenoides antioxydants totaux la plus elevee.
Functional Analysis of the Domain Structure of Tumor Necrosis Factor-α Converting Enzyme*

Many membrane-bound proteins, including cytokines, receptors, and growth factors, are proteolytically cleaved to release a soluble form of their extracellular domain. The tumor necrosis factor (TNF)-α converting enzyme (TACE/ADAM-17) is a transmembrane metalloproteinase responsible for the proteolytic release or “shedding” of several cell-surface proteins, including TNF and p75 TNFR. We established a TACE-reconstitution system using TACE-deficient cells co-transfected with TACE and substrate cDNAs to study TACE function and regulation. Using the TACE-reconstitution system, we identified two additional substrates of TACE, interleukin (IL)-1R-II and p55 TNFR. Using truncations and chimeric constructs of TACE and another ADAM family member, ADAM-10, we studied the function of the different domains of TACE in three shedding activities. We found that TACE must be expressed with its membrane-anchoring domain for phorbol ester-stimulated shedding of TNF, p75 TNFR, and IL-1R-II, but that the cytoplasmic domain is not required for the shedding of these substrates. The catalytic domain of ADAM-10 could not be functionally substituted for that of TACE. IL-1R-II shedding required the cysteine-rich domain of TACE as well as the catalytic domain, whereas TNF and p75 TNFR shedding required only the tethered TACE catalytic domain.
Évaluation d'un modèle dynamique de croissance et de développement de la tomate (Lycopersicon esculentum Mill), TOMGRO, pour différents niveaux d'offre et de demande en assimilats

Le modele TOMGRO, modele de croissance et de developpement de la tomate, a ete evalue pour differents niveaux d'activite des sources et des puits d'assimilats, crees par un enrichissement en CO 2 et par la taille des inflorescences. Notre objectif principal etant de tester les hypotheses de repartition des assimilats et la fonction de nouaison des fruits, les parametres du modele de photosynthese ont ete ajustes de maniere a bien simuler la production journaliere de matiere seche. Les principaux parametres d'entree pour les sous-modeles de croissance et de developpement ont ete mesures experimentalement. Ainsi ajuste, le modele simule bien la croissance en surface des feuilles, mais ne prend pas en compte les variations de stocks d'assimilats au niveau des feuilles, et leurs repercussions probables sur la masse foliaire [. ]
Function of the stromal processing peptidase in the chloroplast import pathway

Chloroplast biogenesis depends on the import of a large diversity of proteins synthesized as precursors in the cytosol. The N-terminal targeting signal, the transit peptide, is proteolytically removed as proteins enter the organelle by a stromal processing peptidase (SPP) in a regulated series of steps. SPP contains a signature HXXEH zinc-binding motif found in members of the M16 metallopeptidase family, which includes, most notably, the mitochondrial processing peptidase. Here we discuss: (i) the broad range of substrates cleaved by SPP, yielding mature proteins for the numerous biosynthetic pathways of the organelle; (ii) the structural features that reside in both SPP and the transit peptide that determine the high specificity of precursor cleavage; (iii) the downregulation of SPP in vivo which shows that it is essential for plant survival; and (iv) the relationship between SPP from higher plants and proteases in several lower eukaryotes and the cyanobacteria.
How to Combine Long and Short Return Histories Efficiently

A common challenge in portfolio risk analysis is that certain assets have shorter return histories than others. Unfortunately, many standard portfolio risk analysis techniques—including historical tail risk measurement, regime-dependent risk analysis, and bootstrapping simulations—require full return histories for all assets or risk factors. The author presents easy instructions on how to efficiently combine data for investments whose histories differ in length and offers a new model to better account for non-normal distributions. A common challenge in portfolio risk analysis is that certain assets have shorter return histories than others. Unfortunately, many standard portfolio risk analysis techniques—including historical tail risk measurement, regime-dependent risk analysis, and bootstrapping simulations—require full return histories for all assets or risk factors. To address this problem, analysts often discard potentially valuable data on assets with long histories. For example, the history of returns for bonds and equities in the United States is a rich one, going back to the 1920s. This data sample includes the Great Depression, wars, several business cycles, periods of hyperinflation and deflation, and various financial crises. Analysts often exclude most of this rich data sample because returns for the other assets in the portfolio are not available as far back in history. Consequently, their models may not capture important risk dynamics for both assets with long return histories and assets with short return histories. In this article, the author presents easy instructions on how to efficiently combine data for investments whose histories differ in length and suggests a new model to better account for non-normal distributions. The new model backfills the missing data for assets with short return histories. (Of course, the author does not claim to offer a model that magically transforms missing data into additional information. The model merely makes it easier to incorporate information from the long sample and to analyze more regimes than those included in the short sample.) Importantly, unlike conventional approaches that rely on the normal distribution, the model samples empirical residuals from the short sample to model uncertainty around the backfilled returns. Essentially, the model represents a hybrid between maximum likelihood estimation and bootstrapping. It provides an easy, simple, relatively assumption-free approach to account for fat tails—and other features of the distribution—in the return-backfilling process beyond means and covariances.
Degrading Mimosine and Tannins of Leucaena leucocephala by Ensiling

Lucaena (Leucaena leucocephala) is a valuable fodder tree, but it contains high contents of anti-nutritional factors, such as mimosine and tannins. The present study investigated the silage fermentation characteristics and ensiling effects on the degradation of mimosine and tannins of leucaena. Mimosine and tannins gradually reduced during ensiling, and sucrose and lactic acid bacteria (LAB) addition promoted their degradation. The highest degradation rate of mimosine was 49.0% in sucrose treatment and the lowest was 25.5% in the control. The highest degradation rate of tannins was 54.7% in the combined treatment of sucrose and LAB and the lowest was 40% in the control. The degradation rates of mimosine and tannins had negative correlation with the pH value and had positive correlation with lactic acid content in silage.
Population Differences in Quantitative Characters as Opposed to Gene Frequencies

In a recent paper, Lewontin (1984) argued that no useful purpose can be served by comparing the variation of gene frequencies of local groups with variation of quantitative characters. He compared (a) the statistical significance of population differences in a quantitative character with (b) the significance of gene-frequency differences at individual loci contributing to variance in the quantitative character and showed that significance in one does not necessarily imply significance in the other. In view of this, Lewontin concluded that comparisons of these types of data serve no useful purpose. I argue here that this conclusion does not follow from his argument. Lewontin was able to construct examples in which significant differences in a quantitative character occur without significant gene-frequency differences (or the converse). The relevance of such examples depends on the frequency with which they occur in nature, that is, the frequency with which they are produced by evolution. Lewontin, however, took population differences in gene frequencies as givens rather than as random variables. Since his analysis proceeds from assumptions about the outcome of evolution, it tells nothing about the frequency with which such outcomes are produced by evolution. For example, it does not exclude the possibility that the examples he chose are events of negligible probability. Consequently, it provides no basis for conclusions conce tling the value of comparing differences in gene frequencies with those in quantitative characters. What, then, are the prospects for using such comparisons to test hypotheses about evolution? Inference is possible provided only that the results of such comparisons can be expected to differ under different evolutionary models. As I discuss below, models of genetic drift and migration seem particularly useful as a basis for generating testable hypotheses. Wright (1943, 1951) showed, using a model of additive gene effects at a single locus, that variation among populations in the value of a selectively neutral quantitative character is, in expectation, 2B = 2FST 20, where U2 is the genetic variance expected under panmixia with the same gene frequencies, and FST is the correlation among uniting gametes relative to the total population. Here, FST is a parameter of the evolutionary process (not a statistic) and depends on individual mobility and the sizes of local populations. Since it is nearly independent of the mean gene frequency for loci that are not near fixation (Rogers 1982), FST can be estimated from any sample of neutral loci. It is also possible to estimate abr using standard methods of quantitative genetics. Thus, the right-hand side of this equation can be estimated from genetic data, if some set of genetic markers is
The Role of Soil Chemistry in the Geographic Distribution of Ceanothus otayensis (Rhamnaceae)

Abstract Ceanothus otayensis McMinn (Rhamnaceae) was previously known only from metavolcanic-derived soils of the northern Peninsular Ranges—predominantly the San Ysidro Mountains—in San Diego County, California, and adjacent Baja California, Mexico. Recently, a new population of C. otayensis was discovered on sedimentary soils at Marine Corps Air Station Miramar, 25 km northwest of the next nearest known population. Sedimentary deposits at the new locality are thought to produce unusual soils. It is possible that the disjunct distribution of C. otayensis is a response to soil conditions, a phenomenon frequently seen in other members of Ceanothus, for instance on serpentine. The present study uses soil chemistry data for seven populations and subpopulations of C. otayensis (metavolcanic: n = 5; sedimentary: n = 2), as well as 22 populations of closely related Ceanothus, to determine whether soils of C. otayensis are chemically distinct from those of closely related Ceanothus, and answer the following question: are sedimentary-derived soils at the new locality chemically similar to metavolcanic-derived soils that support all other known populations of the species? Soils of C. otayensis proved to be chemically distinct from soils of closely related Ceanothus, with significantly lower levels of nitrate, sulfur, and conductivity. Sedimentary and metavolcanic soils of C. otayensis proved to be chemically indistinguishable from one another (P < 0.05), with low levels of all assayed nutrients other than Ca, suggesting a chemical similarity among the soils of C. otayensis that may help explain its disjunct distribution. Population size estimates indicate that the new disjunct locality at Marine Corps Air Station Miramar supports about 75 adult individuals.
IMPACT OF FINANCIAL CONSTRAINTS ON INNOVATION: WHAT CAN BE LEARNED FROM A DIRECT MEASURE?

This paper examines the impact of financial constraints on innovation for established firms. We make use of a direct measure of the existence of financial constraints obtained thanks to a specific survey addressed to French established firms. This is a distinctive feature of this paper as most of previous studies had to rely on proxies (like the cash-flow sensitivity), which may be subject to interpretation problems. The probability to have innovative activities and the probability to face financial constraints are simultaneously estimated by a recursive bivariate probit model. Accounting for the endogeneity of the financial constraint variable, we find that financial constraints significantly reduce the likelihood that firms have innovative activities. The probability to encounter financial constraints is explained by firms’ ex ante financing structure and economic performances.
RELATION OF PHYSICAL ACTIVITY TO MEMORY FUNCTIONING IN OLDER ADULTS: THE MEMORY WORKOUT PROGRAM

This paper describes a Phase I pilot study for the future development and field testing of a prototype CD-ROM program called the MEMORY WORKOUT. The MEMORY WORKOUT helps older adults increase and monitor changes in their daily physical and cognitive activity levels and these effects on physical functioning and memory. A holistic, multimodal model of memory provides the theoretical base for the design of the program. The primary purpose of this program is to enhance users' appreciation for the immediate and longer term benefits of exercise and physical activity on daily mental and physical function. Phase I results with 24 older adults (mean age = 71.2 years) indicate significant cross-sectional relationships among exercise time, exercise efficacy, and word list memory, and moderate to strong interest in improving memory and physical activity. Using Phase I prototype information, the goal of a Phase II project is to produce a complete, interactive, multimedia CD-ROM program that includes fitness training, assessment, and simulation components that are appropriate for adults over age 60.
Analysis of Chaotic Behavior in Switched Reluctance Motors Using Voltage PWM Regulation

In this paper, the analysis of nonlinear dynamic behavior, especially chaotic behavior, in switched reluctance (SR) motors using voltage PWM regulation is carried out. It is identified that the highly uneven distributions of both current and torque of each phase winding during voltage PWM regulation make the SR motor drive prone to chaos. Based on the derivation of the Poincaré map of the SR motor drive, the normal periodic, abnormal periodic, and chaotic behaviors are analyzed by computer simulation. Also, bifurcation diagrams with respect to the speed feedback gain, load torque, and reference speed are presented. These diagrams facilitate the investigation of the route to chaos under different parameters of the drive system.