scholarly journals Epibenthic Harmful Marine Dinoflagellates from Fuerteventura (Canary Islands), with Special Reference to the Ciguatoxin-Producing Gambierdiscus

2020 ◽  
Vol 8 (11) ◽  
pp. 909
Author(s):  
Isabel Bravo ◽  
Francisco Rodríguez ◽  
Isabel Ramilo ◽  
Julio Afonso-Carrillo
Keyword(s):  
Canary Islands ◽  
Abundant Species ◽  
Future Studies ◽  
Marine Food Chain ◽  
Benthic Dinoflagellates ◽  
Wet Weight ◽  
Marine Food ◽  
Marine Dinoflagellates ◽  
Cell Concentrations ◽  
The Relationship

The relationship between the ciguatoxin-producer benthic dinoflagellate Gambierdiscus and other epibenthic dinoflagellates in the Canary Islands was examined in macrophyte samples obtained from two locations of Fuerteventura Island in September 2016. The genera examined included Coolia, Gambierdiscus, Ostreopsis, Prorocentrum, Scrippsiella, Sinophysis, and Vulcanodinium. Distinct assemblages among these benthic dinoflagellates and preferential macroalgal communities were observed. Vulcanodinium showed the highest cell concentrations (81.6 × 103 cells gr−1 wet weight macrophyte), followed by Ostreopsis (25.2 × 103 cells gr−1 wet weight macrophyte). These two species were most represented at a station (Playitas) characterized by turfy Rhodophytes. In turn, Gambierdiscus (3.8 × 103 cells gr−1 wet weight macrophyte) and Sinophysis (2.6 × 103 cells gr−1 wet weight macrophyte) were mostly found in a second station (Cotillo) dominated by Rhodophytes and Phaeophytes. The influence of macrophyte’s thallus architecture on the abundance of dinoflagellates was observed. Filamentous morphotypes followed by macroalgae arranged in entangled clumps presented more richness of epiphytic dinoflagellates. Morphometric analysis was applied to Gambierdiscus specimens. By large, G. excentricus was the most abundant species and G. australes occupied the second place. The toxigenic potential of some of the genera/species distributed in the benthic habitats of the Canary coasts, together with the already known presence of ciguatera in the region, merits future studies on possible transmission of their toxins in the marine food chain.

Plankton and Fisheries

2017 ◽  
Author(s):  
Keith Brander
Keyword(s):  
Marine Mammals ◽  
Carbon Fixation ◽  
High Productivity ◽  
Boundary Currents ◽  
Marine Food Chain ◽  
Shelf Seas ◽  
Plankton Production ◽  
Eastern Boundary Currents ◽  
Marine Food ◽  
The Relationship

This chapter explores the dependence of fish on plankton and the relationship between plankton productivity and fisheries production. The dependence of fish production on plankton production is self-evident, since carbon fixation by photosynthetic phytoplankton forms the base of the marine food chain that leads to fish. Fisheries production is highest in areas of high plankton production, including upwelling areas (e.g. eastern boundary currents), fronts, and shelf seas with high nutrient supply. Marine mammals, seabirds, and fish that are capable of migrating over long distances often congregate to feed in these high productivity areas. However, it is generally not possible to infer fluctuations in annual fisheries yields from information on primary production, and even the average relationship for the nine areas together may be quite weak.

scholarly journals SMFC as a tool for the removal of hydrocarbons and metals in the marine environment: a concise research update

2021 ◽  
Author(s):  
Edvige Gambino ◽  
Kuppam Chandrasekhar ◽  
Rosa Anna Nastro
Keyword(s):  
Marine Environment ◽  
Microbial Fuel Cells ◽  
Energy Production ◽  
Marine Pollution ◽  
Future Perspectives ◽  
Sediment Remediation ◽  
Marine Food Chain ◽  
Marine Food ◽  
Accumulation Of Pollutants ◽  
Insight Into

AbstractMarine pollution is becoming more and more serious, especially in coastal areas. Because of the sequestration and consequent accumulation of pollutants in sediments (mainly organic compounds and heavy metals), marine environment restoration cannot exempt from effective remediation of sediments themselves. It has been well proven that, after entering into the seawater, these pollutants are biotransformed into their metabolites, which may be more toxic than their parent molecules. Based on their bioavailability and toxic nature, these compounds may accumulate into the living cells of marine organisms. Pollutants bioaccumulation and biomagnification along the marine food chain lead to seafood contamination and human health hazards. Nowadays, different technologies are available for sediment remediation, such as physicochemical, biological, and bioelectrochemical processes. This paper gives an overview of the most recent techniques for marine sediment remediation while presenting sediment-based microbial fuel cells (SMFCs). We discuss the issues, the progress, and future perspectives of SMFC application to the removal of hydrocarbons and metals in the marine environment with concurrent energy production. We give an insight into the possible mechanisms leading to sediment remediation, SMFC energy balance, and future exploitation.

scholarly journals Implications of Autonomous Vehicles for Accessibility and Transport Equity: A Framework Based on Literature

2021 ◽  
Vol 13 (8) ◽  
pp. 4448
Author(s):  
Alberto Dianin ◽  
Elisa Ravazzoli ◽  
Georg Hauger
Keyword(s):  
Conceptual Model ◽  
Transport System ◽  
Urban Areas ◽  
Autonomous Vehicles ◽  
Scientific Literature ◽  
Social Groups ◽  
Future Studies ◽  
Social Accessibility ◽  
The Relationship

Increasing accessibility and balancing its distribution across space and social groups are two fundamental goals to make transport more sustainable and equitable. In the next decades, autonomous vehicles (AVs) could significantly transform the transport system, influencing accessibility and transport equity. In particular, depending on the assumed features of AVs (e.g., private or collective) and the considered spatial, social, and regulative context (e.g., rural or urban areas), impacts may be very different. Nevertheless, research in this field is still limited, and the relationship between AV assumptions and accessibility impacts is still partially unclear. This paper aims to provide a framework of the key and emerging aspects related to the implications of AVs for accessibility and transport equity. To set this framework, we perform an analysis of the scientific literature based on a conceptual model describing the implications of AVs for the distribution of accessibility across space and social groups. We recognize four main expected impacts of AVs on accessibility: (1) accessibility polarization, (2) accessibility sprawl, (3) exacerbation of social accessibility inequities, and (4) alleviation of social accessibility inequities. These impacts are described and analyzed in relation to the main AV assumptions expected to trigger them through different mechanisms. Based on the results, some recommendations for future studies intending to focus on the relation between AVs, accessibility, and transport equity are provided.

Association between obstructive sleep apnea and persistent-postural perceptual dizziness

2021 ◽  
pp. 1-6
Author(s):  
Anand K. Bery ◽  
Jayson Lee Azzi ◽  
Andre Le ◽  
Naomi S. Spitale ◽  
Judith Leech ◽  
...  
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Sensitivity And Specificity ◽  
Berlin Questionnaire ◽  
Future Studies ◽  
Obstructive Sleep ◽  
Chronic Dizziness ◽  
Patients At Risk ◽  
The Mean ◽  
The Relationship

BACKGROUND: Obstructive sleep apnea (OSA) has been linked to vestibular dysfunction, but no prior studies have investigated the relationship between Persistent Postural Perceptual Dizziness (PPPD), a common cause of chronic dizziness, and OSA. OBJECTIVE AND METHODS: We determined the frequency of OSA in an uncontrolled group of PPPD patients from a tertiary dizziness clinic based on polysomnogram (PSG). We then assessed the sensitivity and specificity of common OSA questionnaires in this population. RESULTS: Twenty-five patients with PPPD underwent PSG (mean age 47, 60% female, mean BMI 29.5). A majority, or 56%, of patients were diagnosed with OSA, and in most, the OSA was severe. OSA patients were older (56 years versus 40 years, p = 0.0006) and had higher BMI (32 versus 26, p = 0.0078), but there was no clear gender bias (56% versus 64% female, p = 1.00). The mean sensitivity and specificity of the STOP BANG questionnaire for detecting OSA was 86% and 55%, respectively. Sensitivity and specificity of the Berlin Questionnaire was 79% and 45%, respectively. CONCLUSIONS: The prevalence of OSA was much higher in our small PPPD group than in the general population. Screening questionnaires appear to demonstrate good sensitivity to detect PPPD patients at risk of OSA in this small study. Future studies should confirm these findings and determine whether treatment of OSA improves symptoms in PPPD.

scholarly journals Diversity of Epibionts Associated with Lepidochelys olivacea (Eschscholtz 1829) Sea Turtles Nesting in the Mexican South Pacific

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1734
Author(s):  
Brenda Sarahí Ramos-Rivera ◽  
Himmer Castro-Mondragon ◽  
José Gabriel Kuk-Dzul ◽  
Pedro Flores-Rodríguez ◽  
Rafael Flores-Garza
Keyword(s):  
Data Analysis ◽  
Sea Turtles ◽  
South Pacific ◽  
First Record ◽  
Abundant Species ◽  
Interspecific Relationships ◽  
Lepidochelys Olivacea ◽  
Significant Difference ◽  
The Relationship ◽  
Head Neck

The present study contributes to the knowledge of epibionts recorded on sea turtles that nested on a beach in the South Pacific of Mexico. A total of 125 Lepidochelys olivacea turtles nested on Llano Real beach, Guerrero, Mexico, were examined. We collected 450 conspicuous organisms from 8 species from 43 turtles. The corresponding data analysis was carried out to obtain the relative abundance, the relationship between turtle sizes and the presence of organisms, the similarity of species between the sampling months, and the interspecific relationships between the epibionts and the turtles observed. Chelonibia testudinaria was the most abundant species, while Remora remora was the least abundant species. The turtles were divided into six body sections, with the greatest abundance of these organisms located in the head–neck section of turtles, and there was a significant difference in the size of the turtles that presented epibionts and those that did not. C. testudinaria showed greater similarity between sampling months, and the interspecific relationships recorded were commensalism, parasitism, amensalism, and protocooperation. This research contributes the first record of epibionts in L. olivacea nesting in Guerrero, Mexico.

scholarly journals What Matters for Job Security? Exploring the Relationships among Symbolic, Instrumental Images, and Attractiveness for Corporations in South Korea

2021 ◽  
Vol 13 (9) ◽  
pp. 4854
Author(s):  
Juyeon Oh ◽  
Seunghwan Myeong
Keyword(s):  
Undergraduate Students ◽  
Organizational Context ◽  
Job Security ◽  
Corporate Image ◽  
Causal Claim ◽  
Cross Sectional ◽  
Future Studies ◽  
Collectivistic Cultures ◽  
Symbolic Image ◽  
The Relationship

This study examines the extent to which the symbolic and instrumental images and attractiveness toward an organization are related. This study further focuses on global human resource management and reports findings from two studies: Study 1 uses the data from undergraduate students, and Study 2 cross-validates the findings of Study 1 by using actual data from employees. The distinction of this study from previous works is that the present work focuses on a Korean organizational context (collectivistic cultures) and the differences between the potential applicants and employees in the perception of an organization′s attractiveness. Furthermore, it investigates the relationship between the symbolic and instrumental images toward organizations, unlike existing relative research. The results show that the symbolic and instrumental images are related, and the perceptions of the corporate image differ for the potential applicants and employees in the context of collectivistic cultures. The more competent employees consider their organization to be, the more job security they perceive their organization to provide. Moreover, the symbolic image of being competent is negatively related to the instrumental image of job security. Since this study used cross-sectional data, future studies need to use longitudinal data to establish our model′s causal claim empirically and investigate the underlying reasons behind these differences.

Dreams of Truck Drivers: A Test of the Continuity Hypothesis of Dreaming

2005 ◽  
Vol 25 (2) ◽  
pp. 179-186 ◽  
Author(s):  
Michael Schredl ◽  
Arthur Funkhouser ◽  
Nicole Arn
Keyword(s):  
Empirical Studies ◽  
Truck Drivers ◽  
The Other ◽  
Continuity Hypothesis ◽  
Future Studies ◽  
Daytime Activity ◽  
Close Relationship ◽  
The One ◽  
Dream Emotions ◽  
The Relationship

Empirical studies largely support the continuity hypothesis of dreaming. The present study investigated the frequency and emotional tone of dreams of truck drivers. On the one hand, the findings of the present study partly support the continuity regarding the time spent with driving/being in the truck and driving dreams and, on the other hand, a close relationship was found between daytime mood (feelings of stress, job satisfaction) and dream emotions, i.e., different dream characteristics were affected by different aspects of daytime activity. The results, thus, indicate that it is necessary to define very clearly how this continuity is to be conceptualized. The approach of formulating a mathematical model (cf. [1]) should be adopted in future studies in order to specify the factors and their magnitude in the relationship between waking and dreaming.

Perceptions of time at work

2016 ◽  
Vol 45 (1) ◽  
pp. 29-50 ◽  
Author(s):  
Aristides Isidoro Ferreira ◽  
Joana Diniz Esteves
Keyword(s):  
Gender Differences ◽  
Design Methodology ◽  
Internet Use ◽  
The Internet ◽  
Content Type ◽  
Future Studies ◽  
Work Related ◽  
Phone Calls ◽  
Working Day ◽  
The Relationship

Purpose – Activities such as making personal phone calls, surfing on the internet, booking personal appointments or chatting with colleagues may or may not deviate attentions from work. With this in mind, the purpose of this paper is to examine gender differences and motivations behind personal activities employees do at work, as well as individuals’ perception of the time they spend doing these activities. Design/methodology/approach – Data were obtained from 35 individuals (M age=37.06 years; SD=7.80) from a Portuguese information technology company through an ethnographic method including a five-day non-participant direct observation (n=175 observations) and a questionnaire with open-ended questions. Findings – Results revealed that during a five-working-day period of eight hours per day, individuals spent around 58 minutes doing personal activities. During this time, individuals engaged mainly in socializing through conversation, internet use, smoking and taking coffee breaks. Results revealed that employees did not perceive the time they spent on non-work realted activities accurately, as the values of these perceptions were lower than the actual time. Moreover, through HLM, the findings showed that the time spent on conversation and internet use was moderated by the relationship between gender and the leisure vs home-related motivations associated with each personal activity developed at work. Originality/value – This study contributes to the literature on human resource management because it reveals how employees often perceive the time they spend on non-work related activities performed at work inaccurately. This study highlights the importance of including individual motivations when studying gender differences and personal activities performed at work. The current research discusses implications for practitioners and outlines suggestions for future studies.

The optimism-pessimism ratio as predictor of employee creativity: the promise of duality

2018 ◽  
Vol 21 (3) ◽  
pp. 423-442 ◽  
Author(s):  
Arménio Rego ◽  
Miguel Pina e Cunha ◽  
Dálcio Reis Júnior ◽  
Cátia Anastácio ◽  
Moriel Savagnago
Keyword(s):  
Cross Sectional ◽  
Content Type ◽  
Future Studies ◽  
Positive Effects ◽  
The Status ◽  
Single Moment ◽  
Quasi Experimental ◽  
Creativity And Innovation ◽  
The Relationship ◽  
Practical Implications

Purpose The purpose of this paper is to study if the employees’ optimism-pessimism ratio predicts their creativity. Design/methodology/approach In total, 134 employees reported their optimism and pessimism, and the respective supervisors described the employees’ creativity. Findings The relationship between the optimism-pessimism ratio and creativity is curvilinear (inverted U-shaped); beyond a certain level of the optimism-pessimism ratio, the positive relationship between the ratio and creativity weakens, suggesting that the possible positive effects of (high) optimism may be weakened by a very low level of pessimism. Research limitations/implications Being cross-sectional, the study examines neither the causal links between the optimism-pessimism ratio and creativity nor other plausible causal links. The study was carried out at a single moment and did not capture the dynamics that occur over the course of time involving changes in optimism/pessimism and creativity. Future studies may adopt longitudinal or quasi-experimental designs. Practical implications Managers and organizations must consider that, even though positivity promotes creativity, some level of negativity may help positivity to produce creativity. Originality/value This study suggests that scholars who want to study the antecedents of creativity (and innovation) must be cautious in focusing only on the positive or the negative sides of individuals’ characteristics, and rather they must explore the interplay between both poles. Individuals may experience both positive and negative states/traits (Smith et al., 2016), and this both/and approach may impel them to think divergently, to challenge the status quo and to propose “out the box” and useful ideas.

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