scholarly journals Insights into the late-Sixties taxocenosis of Oniscidea from the Pontine islands (West Mediterranean) (Peracarida: Isopoda)

2019 ◽  
Vol 51 (2) ◽  
pp. 217-223
Author(s):  
Gabriele Gentile ◽  
Roberto Argano ◽  
Stefano Taiti
Keyword(s):  
Research Program ◽  
Environmental Conditions ◽  
Small Island ◽  
National Council ◽  
Tyrrhenian Sea ◽  
Number Of Species ◽  
Pontine Islands ◽  
Volcanic Islands ◽  
Very High

We report and discuss faunistic data of Oniscidea inhabiting the Pontine islands, a group of five small volcanic islands and several islets in the Tyrrhenian Sea, located about 60 km from the Italian mainland. Data here presented were primarily obtained from the examination of the material collected during a three-year (1965-1968) research program supported by the Italian National Council of Research and aimed at investigating Mediterranean small island faunas, including Oniscidea. Despite the sampling was not specifically directed at Oniscidea, these data may provide insights into the structure of the Oniscidean taxocenosis of the islands as it existed fifty years ago. Thirty-five species belonging to 11 families, 8 ecological and 7 biogeographical classes were found on these islands. Such number of species of Oniscidea is very high, if we consider the low number of islands and their small sizes. Changes in climate and environmental conditions occurred in the last fifty years would call for a new investigation.

scholarly journals Evaluating the correlation between area, environmental heterogeneity, and species richness using terrestrial isopods (Oniscidea) from the Pontine Islands (West Mediterranean)

2021 ◽  
Author(s):  
Gabriele Gentile ◽  
Roberto Argano ◽  
Stefano Taiti
Keyword(s):  
Species Richness ◽  
Environmental Heterogeneity ◽  
Geographic Distance ◽  
Habitat Diversity ◽  
Tyrrhenian Sea ◽  
Island Species ◽  
Random Placement ◽  
Species Area ◽  
Pontine Islands ◽  
Volcanic Islands

AbstractArea and environmental heterogeneity influence species richness in islands. Whether area or environmental heterogeneity is more relevant in determining species richness is a central issue in island biogeography. Several models have been proposed, addressing the issue, and they can be reconducted to three main hypotheses developed to explain the species-area relationship: (1) the area-per se hypothesis (known also as the extinction-colonisation equilibrium), (2) the random placement (passive sampling), and the (3) environmental heterogeneity (habitat diversity). In this paper, considering also the possible influence of geographic distance on island species richness, we explore the correlation between area, environmental heterogeneity, and species richness by using faunistic data of Oniscidea inhabiting the Pontine Islands, a group of five small volcanic islands and several islets in the Tyrrhenian Sea, located about 60 km from the Italian mainland. We found that the colonisation of large Pontine Islands may occur via processes independent of geographic distance which could instead be an important factor at a much smaller scale. Such processes may be driven by a combination of anthropogenic influences and natural events. Even in very small-size island systems, environmental heterogeneity mostly contributes to species richness. Environmental heterogeneity could influence the taxocenosis structure and, ultimately, the number of species of Oniscidea via direct and indirect effects, these last mediated by area which may or may not have a direct effect on species richness.

scholarly journals New Approaches for the Observation of Transient Phenomena in Critical Marine Environment

2021 ◽  
Vol 9 (6) ◽  
pp. 578
Author(s):  
Roberta Ferretti ◽  
Massimo Caccia ◽  
Massimo Coltorti ◽  
Roberta Ivaldi
Keyword(s):  
Mediterranean Sea ◽  
Marine Environment ◽  
Environmental Conditions ◽  
Marine Environments ◽  
Transient Phenomena ◽  
New Approaches ◽  
Marine Vehicles ◽  
New Methodologies ◽  
Biogeochemical Parameters ◽  
Very High

This paper focuses on the development of new approaches to observe transient phenomena in critical marine environments using autonomous marine vehicles (AMVs) for the acquisition of physical and biogeochemical parameters of water and seabed characterization. The connection with metrological principles, together with the adoption of observing methodologies adjustable according to the specific marine environment being studied, allows researchers to obtain results that are reliable, reproducible, and comparable with those obtained through the classic monitoring methodologies. Tests were executed in dramatically dynamic, sensitive, and fragile areas, where the study and application of new methodologies is required to observe phenomena strongly localized in space and requiring very high resolutions, in time. Moreover, the harsh environmental conditions may present risks not only for the quality and quantity of the acquired data but also for the instrumentation and the operators. This is the case, for instance, in polar marine environments in proximity of tidal glaciers and in the Mediterranean Sea in areas characterized by seabed degassing activities, where AMV-supported monitoring procedures can allow for the safe observation of not repeatable and not completely predictable events.

Culture and context matter: gender in international business and management

2017 ◽  
Vol 24 (2) ◽  
pp. 194-210 ◽  
Author(s):  
Lorraine Eden ◽  
Susan Forquer Gupta
Keyword(s):  
Gender Equality ◽  
International Business ◽  
Gender Inequality ◽  
Research Program ◽  
Social Issues ◽  
Development Program ◽  
Gender Inequalities ◽  
Content Type ◽  
Rich Countries ◽  
Very High

Purpose The purpose of this paper is to argue that culture and context (policy and environment) are key factors affecting gender inequalities within and across countries. Design/methodology/approach This paper applies conceptual and descriptive statistics. Findings The authors found evidence of increasing gender equality in the workplace, but only for rich countries. Gender inequalities persist in the poorest countries, and the gap between rich and poor countries appears to be widening not narrowing. Research limitations/implications This paper demonstrates the need for a comprehensive research program on gender and international business. Practical implications The authors provided useful statistics that could possibly be picked up by newspapers. The paper also highlights the need for a more sustained research program on gender and development. Social implications This paper demonstrates that the public perception of increasing gender equality applies only in very high development (rich) countries. In fact, gender inequality rises as economic development levels decline across countries, and the gap between very high and low countries has widened over the past 15 years. Originality/value The empirical findings with respect to gender inequality across United Nations Development Program country categories over time are, to the best of the authors’ knowledge, novel and original. Relating the gender inequality gap to culture and context highlights the roles that social issues and the environment play in affecting gender inequality across countries and across time.

scholarly journals Hydrogeological conceptual model of andesitic watersheds revealed by high-resolution heliborne geophysics

2019 ◽  
Vol 23 (5) ◽  
pp. 2321-2338 ◽  
Author(s):  
Benoit Vittecoq ◽  
Pierre-Alexandre Reninger ◽  
Frédéric Lacquement ◽  
Guillaume Martelet ◽  
Sophie Violette
Keyword(s):  
Hydraulic Conductivity ◽  
Conceptual Model ◽  
Preferential Flow ◽  
Groundwater Resources ◽  
Watershed Scale ◽  
Volcanic Island ◽  
Multidisciplinary Study ◽  
Hydrogeological Characteristics ◽  
Volcanic Islands ◽  
Very High

Abstract. We conducted a multidisciplinary study at the watershed scale of an andesitic-type volcanic island in order to better characterize the hydrogeological functioning of aquifers and to better evaluate groundwater resources. A heliborne Time Domain ElectroMagnetic (TDEM) survey was conducted over Martinique in order to investigate underground volcanic structures and lithology, characterized by high lateral and vertical geological variability and resulting in a very high heterogeneity of their hydrogeological characteristics. Correlations were made on three adjacent watersheds between resistivity data along flight lines and geological and hydrogeological data from 51 boreholes and 24 springs, showing that the younger the formations, the higher their resistivity. Correlation between resistivity, geology and transmissivity data of three aquifers is attested: within the interval 10–100 ohm m and within a range of 1 to 5.5 Ma, the older the formation, the lower its resistivity, and the older the formation, the higher its transmissivity. Moreover, we demonstrate that the main geological structures lead to preferential flow circulations and that hydrogeological watersheds can differ from topographical watersheds. The consequence is that, even if the topographical watershed is small, underground flows from an adjacent watershed can add significant amounts of water to such a catchment. This effect is amplified when lava domes and their roots are situated upstream, as they present very high hydraulic conductivity leading to deep preferential groundwater flow circulations. We also reveal, unlike basaltic-type volcanic islands, that hydraulic conductivity increases with age in this andesitic-type volcanic island. This trend is interpreted as the consequence of tectonic fracturing associated with earthquakes in this subduction zone, related to andesitic volcanic islands. Finally, our approach allows characterization in detail of the hydrogeological functioning and identification of the properties of the main aquifer and aquitard units, leading to the proposition of a hydrogeological conceptual model at the watershed scale. This working scale seems particularly suitable due to the complexity of edifices, with heterogeneous geological formations presenting high lateral and vertical variability. Moreover, our study offers new guidelines for accurate correlations between resistivity, geology and hydraulic conductivity for volcanic islands. Finally, our results will also help stakeholders toward a better management of water resources.

scholarly journals High prevalence of campylobacter excretors among Liberian children related to environmental conditions

1988 ◽  
Vol 100 (2) ◽  
pp. 227-237 ◽  
Author(s):  
Kåre Mølbak ◽  
Niels Højlyng ◽  
Knud Gaarslev
Keyword(s):  
Environmental Contamination ◽  
Environmental Conditions ◽  
High Intensity ◽  
Bacterial Pathogen ◽  
Urban Slum ◽  
Pathogenic Role ◽  
High Prevalence ◽  
Very High

SUMMARYCampylobacter was the bacterial pathogen most prevalent in 850 children, aged 6–59 months, examined in a house-to-house diarrhoea survey in two Liberian communities. 44·9% of the children from an urban slum and 28·4% from a rural area were excretors. Since the prevalence of diarrhoea was very high and consequently many convalescent carriers were found, it was not possible to evaluate the pathogenic role of campylobacter.The excretor rate increased with ago and was significantly correlated to the uso of supplementary feeding, inversely correlated to the quality of the water supply, and also associated with helminthic infestation. Results from re-examination of 172 children suggested a high intensity of transmission.The findings all indicate the existence of a heavy environmental contamination with campylobacter, probably of both human and animal faecal origin.

scholarly journals Hydrogeological conceptual model of andesitic watersheds revealed by high-resolution geophysics

2019 ◽  
Author(s):  
Benoit Vittecoq ◽  
Pierre-Alexandre Reninger ◽  
Frédéric Lacquement ◽  
Guillaume Martelet ◽  
Sophie Violette
Keyword(s):  
Hydraulic Conductivity ◽  
Conceptual Model ◽  
Subduction Zones ◽  
Preferential Flow ◽  
Watershed Scale ◽  
Volcanic Island ◽  
Hydrogeological Characteristics ◽  
Volcanic Islands ◽  
Very High ◽  
Vertical Variability

Abstract. We conducted a multidisciplinary study at the watershed scale of an andesitic-type volcanic island in order to better characterize the hydrogeological functioning of aquifers and to better evaluate groundwater resource. A helicopter-borne TDEM survey was conducted in 2013 over Martinique Island in order to investigate underground volcanic structures and lithology, characterized by high lateral and vertical variability, and resulting in a very high heterogeneity of their hydrogeological characteristics. Correlations were made on three adjacent watersheds between resistivity data along flight lines and geological and hydrogeological data from 51 boreholes and 24 springs, showing that the younger the formations, the higher their resistivity. Correlation between resistivity, geology and transmissivity data of three aquifers is attested: the older the formation, the lower its resistivity, and the higher its transmissivity. Moreover, we demonstrate that the main geological structures lead to preferential flow circulations and that hydrogeological watershed can differ from topographical watershed. The consequence is that even if the topographical watershed is small, underground flow circulations can add significant amount of water to river watershed’s water balance. This effect is amplified when lava domes and their roots are situated upstream, as they present very high hydraulic conductivity leading to deep preferential groundwater flow circulations. We also reveal, unlike basaltic-type volcanic islands, that hydraulic conductivity increases with age in this andesitic-type volcanic island. This trend is interpreted as the consequence of tectonic fracturing associated to earthquakes in subduction zones associated to andesitic volcanic islands. Finally, our approach allows characterizing in detail the hydrogeological functioning and identifying the properties of the main aquifer and aquitard units, leading to the proposition of a hydrogeological conceptual model at the watershed scale. This working scale seems particularly suitable due to the complexity of edifices, with heterogeneous geological formations presenting high lateral and vertical variability. Moreover, our study offers new guidelines for accurate correlations between resistivity, geology and hydraulic conductivity for volcanic islands. Finally, our results will also help stakeholders toward a better management of water resource.

scholarly journals COMPARISON OF MPPT ALGORITHMS FOR PHOTOVOLTAIC SYSTEMS UNDER UNIFORM IRRIADIANCE BETWEEN PSO AND P&O

2020 ◽  
Vol 4 (10) ◽  
pp. 68-77
Author(s):  
Ahmed Hossam EL-Din ◽  
S.S Mekhamer ◽  
Hadi M.El-Helw
Keyword(s):  
Particle Swarm Optimization ◽  
Conventional Method ◽  
Environmental Conditions ◽  
Hardware Implementation ◽  
Low Cost ◽  
Main Idea ◽  
Photovoltaic Systems ◽  
Swarm Optimization ◽  
Tracking Method ◽  
Very High

This paper shows a Comparison between Conventional Method [P&O] and particle swarm optimization [PSO] Based on MPPT Algorithms for Photovoltaic Systems under uniform irradiance and temperature. The main idea is to show that PSO method has a very high tracking speed and has the ability to track MPP under different environmental conditions in addition to an easy hardware implementation using a low-cost microcontroller. MATLAB simulations are carried out under very challenging conditions, namely irradiance and temperature, which reflect a change in the load [KW]. The proposed PSO tracking method Results will be compared with conventional method called [P&O] through MATLAB/SIMULINK.

scholarly journals Identification of Coastal Vulnerability at The North Pagai Island of Mentawai Using Smartline Method

2017 ◽  
Vol 1 (2) ◽  
pp. 130
Author(s):  
Herdiana Mutmainah ◽  
Aprizon Putra
Keyword(s):  
Negative Impact ◽  
Practical Method ◽  
Small Island ◽  
Physical Aspect ◽  
Coastal Vulnerability ◽  
Coastal Morphology ◽  
The North ◽  
Strong Winds ◽  
High Level ◽  
Very High

Climate change and global warming have a negative impact on coastal, especially small islands. Abration and floods can be very danger and need response to minimize the disaster risks. A simple and practical method is needed to inform the location and type of coastal vulnerability and its risks along coastal segments. Smartline is a coastal management method that represents the geomorphology of coastal, hinterland and shoreline. The North Pagai is a small island, a part of the Mentawai Islands that located at the west offshore of Sumatra Island and one of the under developed areas in Indonesia. The island is surrounded by the Hindia Ocean and located on a subduction path of tectonic plate that prone to earthquakes and Tsunami. High rainfall, strong winds, the complexity of coastal morphology and also the majority of coastal residents and limited infrastructure make the problems more complicated. Tsunami in 2010 (7.7 Mw) caused the change of shoreline getting worst on The East Coast of The North Pagai Island. This study aims to identify the coastal vulnerability using Smartline method. The research was conducted on April and September 2016. The result concludes that physical aspect shows Saumangaya and Matobe Village at high and also very high level of vulnerability hence Sikakap Village at very high level. The socio-economic aspect shows that The Sikakap Village is more advanced but contrary more vulnerable to disaster in terms of population density and complex activities. The North Pagai Island is a vulnerable island from physical and socio-economic aspects.

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