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Number of results: 6
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Abstract

Nothofagaceae fossil leaves and an associated palynoflora from Late Cretaceous sediments of Vega Island, eastern Antarctic Peninsula, are presented. The leaves are described as Nothofagus sp. 1 and Morphotype LDB 1, and come from the Snow Hill Island (late Campanian-early Maastrichtian) and the López de Bertodano (late Maastrichtian) formations, respectively. The palynoflora obtained from levels immediately above and below the Nothofagus sp. 1 and in the same horizon as the Morphotype LDB 1, included terrestrial and marine elements. In the palynoflora associated with Nothofagus sp. 1, conifers are dominant and pollen grains with Nothofagus affinity are represented by four species: Nothofagidites kaitangataensis (Te Punga) Romero 1973 and Nothofagidites senectus Dettmann and Playford 1968, which belong to the ancestral pollen type, as well as Nothofagidites dorotensis Romero 1973 and Nothofagidites sp. of the brassii-type. Cryptogamic spores, marine dinoflagellate cysts and algae, among others, are part of the assemblage. The palynoflora associated with the Morphotype LDB 1 also contains abundant conifer and angiosperm pollen grains with N. dorotensis as the only Nothofagus species recorded. Marine dinoflagellate cysts are scarce while fungi and phytodebris are common elements. The joint presence of marine and non-marine palynomorphs supports a probable nearshore environment at time of deposition for both units. Pollen and spore evidence suggests a mixed conifer and angiosperm forest, with Podocarpaceae and Nothofagus as the main components, and ferns, lycopods, and mosses in the understory. This forest developed under temperate and moist conditions during the middle Campanian-Maastrichtian.

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Authors and Affiliations

Edgardo Romero
Cecilia R. Amenábar
María C. Zamaloa
Andrea Concheyro
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Abstract

This study investigates cadmium (Cd) accumulation in the plant leaves of juglans regia (walnut) and cydonia oblanga (quince) trees related to traffic emissions on the highway roadside. The plant leaf samples were collected from 20 sites on the D-100 Highway roadside and washed with deionized water before analyzed. Determination of Cd was carried out using an inductively-coupled plasma-mass spectrometer after microwave digestion of the samples. Cd concentration on the plant leaves was found to be between 0.04–0.11 mg/kg. In order to determine the traffic-based emissions, vehicles were counted and an emission inventory was prepared. 0.18 tons of Cd was found to be delivered into the atmosphere every day. Cd accumulation depends on traffic density because there were no residential area and industrial plants. The distribution of Cd accumulation caused by traffic emissions was mapped by using a geographic information system (GIS). The maps showed that the Cd accumulation was high in the areas near the highway and then gradually decreased by moving away from the highway.

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Authors and Affiliations

Merve Çolak
Mahnaz Gümrükçüoğlu
Füsun Boysan
Erkan Baysal
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Abstract

We used via light and scanning electron microscopy to study the leaf epidermis of five Solidago taxa from south-western Poland. Light microscopy was employed to describe the epidermal surface, including stomatal types, the shape of epidermal cell walls, stomatal density, the distribution of stomata between the abaxial and adaxial epidermis, and stomatal guard cell length. From these observations we calculated the stomatal index (SI) and stomatal ratio (SR) as the basis for defining the type of leaf. From LM of transverse sections of leaf we described mesophyll structure, the presence of secretory canals, adaxial and abaxial epidermis thickness, and leaf thickness. We examined cuticular ornamentation, trichome features and epicuticular secretions by SEM. As determined by discriminatory analysis, the most important traits distinguishing these taxa were the stomatal index of the adaxial epidermis, leaf thickness, features of the walls of epidermal cells, and the presence and features of trichomes. On the basis of observations and measurements we created a key for distinguishing Solidago taxa.

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Authors and Affiliations

Magdalena Szymura
Karol Wolski
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Abstract

In the management of human resources, the absences are monitored with Bradford Factor (BF) using the number and length of sick leaves. The sick leaves are also measured in health technology to assess the impact of health technologies on product loss, aka indirect cost (IC). Linking the BF and IC might promote BF as an outcome measure and facilitate the estimation of IC. We simulate a single company operation in several scenarios describing the firm's functioning and adjustments to workers' absence. We measure the BF and the IC due to absence and relate them with econometric modelling. Results show that BF and IC are associated in a non-linear way; hence, IC cannot be calculated from BF in a simple manner. The association is strongest for possibility to adjust to worker's absence, and a high elasticity of substitution between workers. Therefore, the possibility to proxy IC by BF is rather limited.
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Authors and Affiliations

Beata Koń
1
Michał Jakubczyk
1

  1. SGH Warsaw School of Economics, Decision Analysis and Support Unit
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Abstract

This work presents a comparative analysis of the phenolic composition (UHPLC-PDA-ESI-MS3, HPLC-PDAfingerprint, UV-spectrophotometric methods) and antioxidant activity (DPPH, FRAP) of leaf samples from two vegetation seasons of a medicinal and dietary plant Sorbus domestica growing in its natural habitat (Croatia, C) and cultivated in Poland (P). The samples from both sources were rich in structurally diverse polyphenols (44 analytes; P: 73.4–76.6 and C: 98.3–106.7 mg GAE/g dry leaves) including the dominating flavan-3-ols and flavonoids. The greatest qualitative and quantitative differences were observed for flavonoids (P: 14.3–20.3%; C: 27.5–34.1% of polyphenols) – in the Polish samples flavonoid diglycosides predominated, in the Croatian samples the contents of both monoglycosides and diglycosides were similar. In the case of dry methanolic extracts, despite the higher extraction efficiency obtained for the Croatian samples (32–36% vs 23–24%), the quality of the extracts was comparable, both in terms of the total phenolic content (P: 269.4–280.0; C: 297.6–304.4; mg GAE/g dry extract) and antioxidant activity parameters (DPPH, EC50, μg/mL. P: 10.5–10.9, C: 10.0–10.3; and FRAP, mmol Fe2+/g, P: 6.64–7.13, C: 7.06–7.11). As a result, the study confirmed the influence of environmental conditions on the phenolic profile and antioxidant capacity of S. domestica leaves, as well as showed that despite some differences, plant materials from both Poland and Croatia might be suitable for production of natural health products.

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Authors and Affiliations

Magdalena Rutkowska
Monika Dubicka
Monika A. Olszewska
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Abstract

Petiole bending in detached leaves of Bryophyllum calycinum was intensively investigated in relation to polar auxin transport in petioles. When detached leaves were placed leaf blade face down, clear petiole bending was observed. On the other hand, no petiole bending was found when detached leaves were placed leaf blade face up. Indole-3-acetic acid (IAA) exogenously applied to petioles was significantly effective to induce and/or stimulate petiole bending when detached leaves were placed leaf blade face down. To clarify the mechanisms of petiole bending in detached leaves of B. calycinum when they were placed leaf blade face down, the effects of application of IAA, ethephon which is an ethylene releasing compound, inhibitors of polar auxin transport such as 2,3,5-tiiodobenzoic acid (TIBA), N-1-naphthylphthalamic acid (NPA) and 9-hydroxyfluorene-9-carboxylic acid (HFCA) and methyl jasmonate (JA-Me) were thoroughly investigated. Ethephon was not effective to enhance petiole bending, suggesting that ethylene derived from exogenously applied IAA does not play an important role in petiole bending in detachd leaves of B. calycinum. This suggestion was strongly supported by the fact that ethephon exogenously applied to petioles in intact plant of B. calycinum had no effect on inducing epinasty and/or hyponasty either (Ueda et al., 2018). Potent inhibitors of polar auxin transport, TIBA and HFCA, and JA-Me were extremely effective to inhibit petiole bending but NPA was not. Almost no petiole bending was observed in excised petiole segments without the leaf blade. Applicaton of IAA to the cut surface of petioles in the leaf blade side strongly promoted petiole bending. Polar auxin transport in excised petioles of B. calycinum was intensively investigated using radiolabeled IAA ([1-14C] IAA). Clear polar auxin transport was observed in excised petiole segments, indicating that auxin allows movement in one direction: from the leaf blade side to the stem side in petioles. When detached leaves were placed only leaf blade face down, transported 14C-IAA was reduced in the lower side of the excised petioles. These results strongly suggest that transport and/or lateral movement of endogenous auxin biosynthesized or produced in the leaf blade are necessary to induce petiole bending in detached leaves of B. calycinum. Mechanisms of petiole bending in detached leaves of B. calycinum are also discussed in relation to polar auxin transport and lateral movement of auxin.

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Authors and Affiliations

Junichi Ueda
Kensuke Miyamoto
Justyna Góraj-Koniarska
Marian Saniewski

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