Opportunistic Germination Behaviour of Gypsophila (Caryophyllaceae) in Two Priority Habitats from Semi-arid Mediterranean Steppes

Gypsophila tomentosa and G. struthium are closely related species, characteristic of two European priority habitats, salt and gypsum inland steppes, respectively. Germination strategies of the two taxa were investigated in plants from two nearby populations, growing under the same climatic conditions but on different types of soil, and belonging to different plant communities. Their germination patterns were studied at five constant temperatures in darkness: 5oC, 10oC, 15oC, 20oC and 25oC, and the base temperature and the thermal time requirement were calculated. As the distribution area of both species is subjected to a Mediterranean continental climate with significant differences between…

Assessing Effects of Temperature Change on Four Limonium Species from Threatened Mediterranean Salt-Affected Habitats

[EN] Evaluation of tolerance to temperatures in the germination stage is an important tool to foresee the possible effect of global warming. Moreover, establishing germination protocols for endemic and threatened species is most interesting for restoration and management plans that focus on habitat conservation. Seed germination was analysed in four species of the genus Limonium (L. virgatum, L. narbonense, L. girardianum and L. santapolense) growing in two saline habitats on the eastern coast of the Iberian Peninsula. The study aim was to compare responses of seed germination to different temperature regimes. Seeds were collected in two protected areas, `L¿Albufera de Valencia¿ (province o…

Electrochemical monitoring of ROS influence on seedlings and germination response to salinity stress of three species of the tribe Inuleae.

Solid-state electrochemical methods have been applied to the establishment of patterns of plant growth and response to saline stress using seedlings of Inula helenium L., Dittrichia viscosa (L.) Greuter (Inula viscosa (L.) Aiton), Limbarda crithmoides (L.) Dumort (Inula crithmoides L.). Upon in situ electrochemical generation of reactive oxygen species (ROS) the reactivity with such species was monitored using voltammetric signals associated to the oxidation of polyphenolic components of the plants. A simple kinetic model based on second-order reaction between ROS and polyphenolic components is applied to electrochemical data yielding apparent rate constants which can be correlated with the…

Responses to salt stress in the halophyte Plantago crassifolia (Plantaginaceae)

Abstract General responses to salt stress have been investigated in the halophyte Plantago crassifolia. Seed germination was strongly inhibited by NaCl, although seed viability and germination capacity were not affected by salt pre-treatments. A concentration-dependent inhibition of plant growth was observed in the presence of NaCl, which was accompanied by the accumulation of Na+ ions in the leaves, as determined by cation exchange HPLC. A 20-fold increase of proline content in leaves was observed when plants were treated with 500 m m NaCl, suggesting a protective role against high salinity stress for this amino acid, whose possible mechanism of action is discussed.

Long-term carbon stock recovery in a neotropical-logged forest

AbstractThis article assesses the effect of different logging levels on loss of above-ground biomass and the contribution of different ecological groups of species in the long-term recovery of C st...

The determinants of increasing equity market comovement: economic or financial integration?

This paper investigates to what extent the substantial increase in exposures of local European equity market returns to global shocks is mainly due to a convergence in cash flows (“economic integration”), to a convergence in discount rates (“financial integration”), or to both. We find that this increased exposure is nearly entirely due to increasing discount-rate betas. This finding is robust to alternative ways of calculating discount-rate and cash-flow shocks.

The Investment Performance of U.S. Islamic Mutual Funds

Islamic investment funds have become increasingly important because of high demand from many investors, including those outside the Muslim investment community. This article compares the performance and risk sensitivity of Islamic mutual funds in the United States with that of their conventional peers. This article also analyzes the performance of Islamic funds, and compares this performance with that of socially responsible investment (SRI) mutual funds. Capital Asset Pricing Model (CAPM)-based methodology was used for the analysis. The results suggest that over the entire study period (1987&ndash

Conservation aspects for chasmophytic species: Phenological behavior and seed strategies of the Central Apennine threatened endemismMoehringia papulosaBertol

Abstract Chasmophytic vegetation growing on the cracks of cliffs in the Mediterranean and in the Euro-Siberian phytogeographic regions shows a great regional diversity, with a large number of endemic plant species, many of them endangered and at risk of extinction. Moehringia papulosa is an example of a threatened plant living in this kind of habitat. It is an endemism of the Marche region in central Italy, whose natural populations are considered as critically endangered (CR) under the IUCN criteria and the habitat is protected by the E.U. (Directive 92/43/EEC) with the habitat 8210 “calcareous rocky slopes with chasmophytic vegetation”. The phenology of natural populations was analyzed, s…

Cytogenetic study of angiosarcoma of the breast.

Angiosarcoma of the breast is quite rare, and the development of cutaneous angiosarcoma after segmental mastectomy and radiation therapy is even less common. A cytogenetic analysis of a mammary angiosarcoma arising in a breast after previous irradiation and segmental mastectomy for infiltrating ductal carcinoma revealed multiple clonal rearrangements involving chromosomes X, 1, 2, 3, 4, 5, 6, 7, 8, 9, 15, 17, 20, and 22. No cytogenetically analyzed angiosarcomas of the breast have been reported before. Genes Chromosom Cancer 10:210–212 (1994). © 1994 Wiley-Liss, Inc.

Genetic variability in the endemic Leucojum valentinum

The genetic variability of Leucojum valentinum Pau (Amaryllidaceae), a vulnerable endemic species restricted to a small area in the region of Valencia (Eastern Spain), has been studied using random amplified polymorphic DNA (RAPD) markers. A total of 197 individuals from eleven populations were studied using 13 RAPD primers. Our results show high variability for the species, low differentiation among populations and uncorrelated levels of genetic variability and population size. Four groups in which three populations (SAG, PUG and COL) are separated from all the others were found, but without connection to geographical location.

Effects of salt stress on the reproductive biology of the halophyte Plantago crassifolia

Floral phenology, pollen quality and seed set of Plantago crassifolia plants, grown in the presence of increasing NaCl concentrations, were studied to test how this Mediterranean halophyte responded to salt stress during the reproductive phase of its life cycle. "Reproductive success" was maximal in plants grown in non-saline conditions, or in the presence of 100 mM NaCl, but it was negatively affected by higher salinities, due to a progressive reduction of pollen fertility, seed set, and seed viability.

Effects of environmental factors on seed germination ofAnthyllis barba-jovisL

Abstract The influence of the main environmental factors on seed germination of Anthyllis barba-jovis L. were analysed. This work is part of a broader investigation aimed at the reintroduction of this species on Mount Conero, Ancona (central Italy), where it is at present extinct. The seeds were collected from the Gargano headland (southern Adriatic coast). Experimental analyses were carried out to determine: (i) dormancy levels of seeds collected in successive years, and also collected from the soil seed bank; (ii) effects of usual pre-treatments for overriding the physical dormancy of the seeds; (iii) optimal temperature range for maximum germination; (iv) effects of fire on seed germinat…

The response of Brent crude oil to the European central bank monetary policy

Este artículo examina el impacto de las decisiones de política monetaria del Banco Central Europeo (BCE) sobre los precios del petróleo y la liquidez mediante un estudio de eventos con datos intradía. Analizamos el período de enero de 1999 a diciembre de 2020, que incluye la crisis financiera que comenzó en agosto de 2007. Nuestros resultados muestran una respuesta significativa de los rendimientos del petróleo solo durante la crisis financiera. Específicamente, encontramos que los rendimientos de los futuros de petróleo crudo Brent respondieron negativamente a variaciones inesperadas en la prima de riesgo italiana como medida de acciones de política monetaria no convencionales, y positivam…

Hydroperiod length as key parameter controlling seed strategies in Mediterranean salt marshes: The case of Halopeplis amplexicaulis

Abstract The comprehension of plant biology and the response to the environment is fundamental to achieve the optimal skills to manage and conserve the fine equilibrium between biotic and abiotic parameters regulating natural biodiversity in salt marshes. The behaviour of annuals living in these stressful conditions is poorly understood and constitutes a good model for a better understanding of this relationship. We thus identified the determinant environmental factors involved in population survival of Halopeplis amplexicaulis, a threatened annual species inhabiting salt marshes. To achieve this objective, maternal climatic parameters were analyzed in seeds collected in different years, an…

Unraveling Salt Tolerance in Halophytes: A Comparative Study on Four Mediterranean Limonium Species with Different Geographic Distribution Patterns

[EN] We have performed an extensive study on the responses to salt stress in four related Limonium halophytes with different geographic distribution patterns, during seed germination and early vegetative growth. The aims of the work were twofold: to establish the basis for the different chorology of these species, and to identify relevant mechanisms of salt tolerance dependent on the control of ion transport and osmolyte accumulation. Seeds were germinated in vitro, in the presence of increasing NaCl concentrations, and subjected to ¿recovery of germination¿ tests; germination percentages and velocity were determined to establish the relative tolerance and competitiveness of the four Limoni…

HalocnemumM. Bieb. vegetation in the Mediterranean Basin

The aim of the article is the syntaxonomic interpretation of hyperhalophilous woody or semi-woody vegetation with Halocnemum M. Bieb. along the coasts of the Mediterranean Basin. For this area, the two species of Halocnemum, H. strobilaceum (Pall.) M. Bieb. and H. cruciatum (Forssk.) Tod. are identified; their morphological characteristics, synonymy and distribution are here described. The study carried out of particular aspects of the plant morphology and the micromorphological characteristics of the seeds collected from different places in the Mediterranean allows to better differentiate the two species. Vegetation studies already done in many communities of the Mediterranean by several a…

New insight on Mediterranean and sub-Mediterranean syntaxa included in the Vegetation Prodrome of Italy

Volatility Transmission Models: A Survey

This study reviews the literature on volatility transmission in order to determine what we have learnt about the different methodologies applied. In particular, GARCH, regime switching and stochastic volatility models are analysed. In addition, this study covers several concrete aspects such as their scope of application, the overlapping problem, the concept of efficiency and asymmetry modelling. Finally, emerging topics and unanswered questions are identified, serving as an agenda for future research.

Aridity level, rainfall pattern and soil features as key factors in germination strategies in salt-affected plant communities

Abstract In arid environments, particularly in halophytic habitats, germination ecophysiology is strongly affected by environmental factors, primarily water availability, which is influenced by quantity and seasonal distribution of precipitation and soil properties. The aim of this paper was to demonstrate that water availability is essential for the control of germination and the response of seedlings growing in saline areas. With this approach, we compared the germination strategies in two Halocnemum populations with contrasting rainfall regimes and soil aridity. The germination behavior and radicle growth under various temperature regimes, light conditions and salinity levels were evalua…

Malignant granular cell tumor of soft tissues: a study of two new cases.

We describe 2 cases of malignant granular cell tumor. A marked discrepancy exists concerning the criteria of malignancy of this rare entity, which was diagnosed in male patients aged 41 and 52 years, respectively. They presented with tumors measuring more then 3.5 cm; one arose in the dermis and subcutaneous tissue in the region of the scapula, whereas the other was situated in deeper soft tissue in the pelvis. One case, with previous diagnosis of benign granular cell tumor, presented local recurrence 2 years after the initial diagnosis. The other case presented a fascicular pattern of growth invading adjacent muscular tissue. Both neoplasms were composed of polygonal and spindle cells, sho…

An electrochemical analysis suggests role of gynodioecy in adaptation to stress in Cortaderia selloana

Cortaderia selloana is an invasive, gynodioecious species prevalent in Mediterranean area which contains both female and hermaphrodite specimens in the wild population. Using voltammetric data we show that the female and hermaphrodite specimens exhibit differential electrochemical response. Cortaderia selloana leaves from two different provenances in the Valencia Mediterranean area, Sueca and Cullera (Comunitat Valenciana, Spain), in the surroundings of the Albufera Natural Park, a peculiar ecosystem containing unspoilt dune beaches and forests, were studied to determine correlation of flower morphology with the plant's ability to adapt to stress conditions. Our data suggests that gynodioec…

Assessing coastal habitats with Juniperus sp. pl. in the Iberian Peninsula and on the Balearic Islands

Coastal habitats with Juniperus sp. pl. represent the mature stage in the ecological succession of dune ecosystems. Maritime junipers (Juniperus macrocarpa), prickly junipers (J. navicularis) and c...

Green and good? The investment performance of US environmental mutual funds

Increased concern for the environment has increased the number of investment opportunities in mutual funds specialized in promoting responsible environmental attitudes. This article examines the performance and risk sensitivities of US green mutual funds vis-a-vis their conventional peers. We also analyze and compare this performance relative to other socially responsible investing (SRI) mutual funds. In order to implement this analysis, we apply a CAPM-based methodology and find that in the 1987–2009 period, environ- mental funds had lower performance than conventional funds with similar characteristics. However, if we focus on a more recent period (2001–2009), green funds achieved adjuste…

An assessment of the floristic composition, structure and possible origin of a liana forest in the Guayana Shield

Liana is a life form that possess high importance in many neotropical forests. Density of climbers apparently increases with the intervention rate (eg. logging). The aim of this work is to characterize the structure, floristic composition and soils of a sector classified as Liana Forest (LF). We identified a LF sector in a not-logged area; three 1 ha square plots were measured (individuals ≥ 10 cm dbh, “diameter at breast height”). In each plot we evaluate four 100 m2 square understory sub-plots (all spermatophyta individuals < 10 cm dbh). LF has a low canopy (< 15 m) and is dominated by Alexa imperatricis and Pentaclethra macroloba. Basal area (20.4 m2ha-1) and diversity (H´= 2.6) ar…

Relaciones suelo-vegetación en una toposecuencia del Escudo Guayanés, Venezuela

El Escudo Guayanés es uno de los territorios más antiguos del planeta; tiene millones de años sometido a procesos de lixiviación y erosión que dejan suelos oligotróficos. El objetivo de este trabajo fue hacer la caracterización de los parámetros físicos y químicos de los suelos, en diferentes comunidades boscosas de la Reserva Forestal Imataca, e identificar ciertas relaciones entre los componentes edáficos y las especies que allí se presentan. Se realizó un inventario de todos los individuos mayores a 10cm dap (diámetro a la altura del pecho) en 15 parcelas (1ha); en cada una de esas parcelas se evaluaron cuatro sub-parcelas de sotobosque (100m²) para contabilizar todas las espermatofitas;…

The organismic and the continuous approaches applied to phytosociological relationships in a lowland neotropical forest, Venezuela

Abstract The Organismic and the Continuous theories are traditionally considered as antagonist in ecology studies. In this research, we make the floristic characterization of different forest communities and establish the corresponding classification, taking into account the approaches derived from the theories aforementioned. We used 1 ha plots to evaluate individuals bigger than 10 cm dbh (diameter at breast height). In each one of that plots, four sub-plots of 100 m2 were measured, to study all the spermatophyta in the understory. The data obtained were considered in an Enlarged Importance Index (EII), for each species in each plot. Then, the phytosociological relationships were establis…

Volatility transmission patterns and terrorist attacks

The objective of this study is to analyze volatility transmission between the US and Eurozone stock markets considering the effects of the September 11, March 11 and July 7 financial crises. In order to do this, we use a multivariate GARCH model and take into account the asymmetric volatility phenomenon, the non-synchronous trading problem and the crises themselves. Moreover, a graphical analysis of the Asymmetric Volatility Impulse-Response Functions (AVIRF) is introduced, which takes into consideration the crisis effect. Results suggest that there is bidirectional and asymmetric volatility transmission and show the different impact that terrorist attacks had on both markets. El objetivo d…

Variations in seed germination behavior ofPhleum hirsutumsubsp.ambiguumand possible applications in semi-natural grassland restoration

Phleum hirsutum Honck. subsp. ambiguum (Ten.) Tzvelev is an important component of the vegetation of some semi-natural grassland habitats of central and southern Italy and especially of those referring to the 6210* habitat (Directive 92/43/EEC). Seeds of this species are required for the execution of restoration works concerning this habitat. Therefore, the recovery and the study of autochthonous germplasm are needed. This study focused on the intra-specific variations in seed mass and size and in seed germination behavior in this species since the knowledge of these aspects can be very useful in the planning of restoration projects. The present research evidenced significant differences in…

Are green bonds a different asset class? Evidence from time-frequency connectedness analysis

Abstract This paper investigates the time-frequency connectedness across the global green bond market and several mainstream financial and energy markets in an attempt to figure out whether green bonds represent a different asset class. The connectedness methodology proposed by Barunik and Křehlik (2018) is employed for that purpose. This approach enables quantifying the dynamics of connectedness in terms of return and volatility over time and across time scales simultaneously. The empirical results indicate that connectedness between the global green bond market and the conventional financial and energy markets mainly occurs at shorter time horizons, suggesting that shocks are rapidly tran…

The Coastal Levantine Area

The Coastal Levantine area is a very diverse territory situated between the Cap de Creus and the Cap de la Nau. The wide variety of environments and ecological conditions that occur in this area determine its great diversity and richness from the vegetation point of view. Forest composition depends mainly on climatic factors, geomorphology and soil features, and are currently dominated by evergreen sclerophyllous (Quercus ilex, Q. rotundifolia, Q. suber), conifer (Pinus halepensis, P. pinaster, P. pinea, P. salzmannii, P. sylvestris), and deciduous (Fagus sylvatica, Quercus petraea) and semi-deciduous (Quercus faginea, Q. canariensis, Q. pubescens, Q. pyrenaica) species in inland areas with…

Nuclear DNA content variation inHalimiumandXolantha(Cistaceae)

Abstract Chromosome numbers and nuclear DNA contents were determined in several taxa of two genera of Cistaceae, Halimium and Xolantha. The diploid chromosome number 2n = 18 is stable within the genus Halimium. In Xolantha, the diploid chromosome number 2n = 14 was confirmed in X. tuberaria, and hexaploid (2n = 36) and octoploid (2n = 48) cytotypes were found in X. guttata. DNA amounts, first reported here for these genera, were determined by flow cytometry of propidium iodide-stained nuclei. Within Halimium there is a more than twofold difference in genome size between H. calycinum (7.61 pg DNA) and H. atriplicifolium (3.66 pg DNA). Within the genus Xolantha, absolute genome sizes of 7.3 a…