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1.
Heliyon ; 10(4): e26233, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38404766

RESUMEN

Satisfaction with learning management systems (LMSs) is an essential indicator of students' e-learning experiences and reflects the quality of e-learning. Applying the technology satisfaction model, the present study aimed to investigate medical and nursing students' satisfaction with LMSs and its predictors. We conducted our survey at a medical university located in East China and received a total of 329 effective responses. Structural equation modelling was used to analyse the data. Our findings confirmed that perceived ease of use and perceived usefulness were two direct predictors of medical and nursing students' satisfaction with LMSs. Furthermore, the influence of perceived usefulness on satisfaction was more powerful than that of perceived ease of use. This study also substantiated that computer self-efficacy and perceived ease of use can indirectly impact medical and nursing students' satisfaction with LMSs. Our research effectively links the theoretical hypotheses with empirical findings, highlighting the central role of Computer Self-Efficacy (CSE), perceived ease of use, and perceived usefulness in shaping medical and nursing students' satisfaction with LMSs. Our findings contributed to the understanding of the technology satisfaction model and medical and nursing students' e-learning during the COVID-19 pandemic.

2.
Int Dent J ; 73(6): 889-895, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37442684

RESUMEN

OBJECTIVES: We aimed to test the psychometric validity of the adapted and translated Self-Management Ability Questionnaire-Short Form (SMAQ-12) to Portuguese. METHODS: The translation and adaptation of the SMAQ-12 followed international guidelines. We included 280 participants with chronic periodontitis from the Department of Periodontology of the Egas Moniz Dental Clinic. Participants completed the Portuguese version of the SMAQ-12 (SMAQ-12-PT), a 12-item scale with 3 conceptual domains (Role Management, Medical Management, and Emotional Management). The validity of the content, its construct and internal consistency, as well as test-retest reliability were used to estimate psychometric properties. RESULTS: The SMAQ-12-PT showed an interclass correlation coefficient value of 0.90, with a 95% confidence interval (0.79-0.95; P < .001) and high reliability (Cronbach alpha coefficient ranging between 0.78 and 0.94). Confirmatory factor analysis revealed adequate model fit, with comparative fit index of 0.853, goodness-of-fit of 0.947, and a 0.052 value of root mean squared error of approximation. CONCLUSIONS: The SMAQ-12-PT was found to be a valid and reliable instrument in the Portuguese population. Disease management representation for the specialty of periodontology and its impact on periodontal schedules and practices should be evaluated in future studies.


Asunto(s)
Periodontitis , Automanejo , Adulto , Humanos , Reproducibilidad de los Resultados , Portugal , Encuestas y Cuestionarios , Psicometría
3.
Clin Exp Dent Res ; 8(2): 552-560, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35191217

RESUMEN

OBJECTIVE: To assess pH values to characterize bottled water in Portugal, being able to provide information for both patients and clinicians about its erosive potential, as a tool to prevent the ingrowing prevalence of dental erosion and its progression, especially in patients who are at greater risk, such as those with dry mouth syndrome, making the dissemination of this knowledge a fundamental tool for clinical decision. MATERIALS AND METHODS: One hundred and five common brands of bottled water (n = 105), commercialized in Portugal, were analyzed. Of these, 73 were smooth water (Group A) and 32 carbonated water (Group B). All pH values were assessed by potentiometric measurement with a calibrated electrode. For each brand, five independent measurements were recorded at 25°C for further calculation of the mean pH value and standard deviation. RESULTS: Focusing on the mean pH values from Group A, one had a pH mean value lower than 5.2, four between 5.2 and 5.5, thirty-seven between 5.5 and 6.8, and thirty-one higher than 6.8. In Group B, ten had a mean pH value lower than 5.2, ten between 5.2 and 5.5, twelve between 5.5 and 6.8, and none above 6.8. CONCLUSIONS: Bottled water, commercialized in Portugal, has different mean pH values, some below the critical threshold of enamel and/or dentin, suggesting that they may have a greater risk of consumption than others, only with respect to the pH parameter of erosive potential. Further investigation concerning this area is needed for wider conclusions.


Asunto(s)
Agua Potable , Erosión de los Dientes , Xerostomía , Carbonatos , Esmalte Dental , Agua Potable/química , Humanos , Concentración de Iones de Hidrógeno , Erosión de los Dientes/epidemiología , Erosión de los Dientes/etiología , Erosión de los Dientes/prevención & control
4.
Molecules ; 27(4)2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35208995

RESUMEN

Lubricants are materials able to reduce friction and/or wear of any type of moving surfaces facilitating smooth operations, maintaining reliable machine functions, and reducing risks of failures while contributing to energy savings. At present, most worldwide used lubricants are derived from crude oil. However, production, usage and disposal of these lubricants have significant impact on environment and health. Hence, there is a growing pressure to reduce demand of this sort of lubricants, which has fostered development and use of green lubricants, as vegetable oil-based lubricants (biolubricants). Despite the ecological benefits of producing/using biolubricants, availability of the required raw materials and agricultural land to create a reliable chain supply is still far from being established. Recently, biomass from some microalgae species has attracted attention due to their capacity to produce high-value lipids/oils for potential lubricants production. Thus, this multidisciplinary work reviews the main chemical-physical characteristics of lubricants and the main attempts and progress on microalgae biomass production for developing oils with pertinent lubricating properties. In addition, potential microalgae strains and chemical modifications to their oils to produce lubricants for different industrial applications are identified. Finally, a guide for microalgae oil selection based on its chemical composition for specific lubricant applications is provided.


Asunto(s)
Biomasa , Lubricantes , Microalgas , Materiales Biocompatibles/química , Reactores Biológicos , Biotecnología , Lubricantes/química , Lubricantes/aislamiento & purificación , Lubrificación , Microalgas/química , Microalgas/crecimiento & desarrollo , Fotosíntesis
5.
Vaccines (Basel) ; 9(10)2021 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-34696266

RESUMEN

BACKGROUND: young adults represent a critical target for mass-vaccination strategies of COVID-19 that aim to achieve herd immunity. Healthcare students, including dental students, are perceived as the upper echelon of health literacy; therefore, their health-related beliefs, attitudes and behaviors influence their peers and communities. The main aim of this study was to synthesize a data-driven model for the predictors of COVID-19 vaccine willingness among dental students. METHODS: a secondary analysis of data extracted from a recently conducted multi-center and multi-national cross-sectional study of dental students' attitudes towards COVID-19 vaccination in 22 countries was carried out utilizing decision tree and regression analyses. Based on previous literature, a proposed conceptual model was developed and tested through a machine learning approach to elicit factors related to dental students' willingness to get the COVID-19 vaccine. RESULTS: machine learning analysis suggested five important predictors of COVID-19 vaccination willingness among dental students globally, i.e., the economic level of the country where the student lives and studies, the individual's trust of the pharmaceutical industry, the individual's misconception of natural immunity, the individual's belief of vaccines risk-benefit-ratio, and the individual's attitudes toward novel vaccines. CONCLUSIONS: according to the socio-ecological theory, the country's economic level was the only contextual predictor, while the rest were individual predictors. Future research is recommended to be designed in a longitudinal fashion to facilitate evaluating the proposed model. The interventions of controlling vaccine hesitancy among the youth population may benefit from improving their views of the risk-benefit ratio of COVID-19 vaccines. Moreover, healthcare students, including dental students, will likely benefit from increasing their awareness of immunization and infectious diseases through curricular amendments.

6.
Vaccines (Basel) ; 9(6)2021 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-34072500

RESUMEN

BACKGROUND: Acceleration of mass vaccination strategies is the only pathway to overcome the COVID-19 pandemic. Healthcare professionals and students have a key role in shaping public opinion about vaccines. This study aimed to evaluate the attitudes of dental students globally towards COVID-19 vaccines and explore the potential drivers for students' acceptance levels. METHODS: A global cross-sectional study was carried out in February 2021 using an online questionnaire. The study was liaised by the scientific committee of the International Association of Dental Students (IADS), and data were collected through the national and local coordinators of IADS member organizations. The dependent variable was the willingness to take the COVID-19 vaccine, and the independent variables included demographic characteristics, COVID-19-related experience, and the drivers of COVID-19 vaccine-related attitude suggested by the WHO SAGE. RESULTS: A total of 6639 students from 22 countries, representing all world regions, responded to the questionnaire properly. Their mean age was 22.1 ± 2.8 (17-40) years, and the majority were females (70.5%), in clinical years (66.8%), and from upper-middle-income economies (45.7%). In general, 22.5% of dental students worldwide were hesitant, and 13.9% rejected COVID-19 vaccines. The students in low- and lower-middle-income (LLMI) economies had significantly higher levels of vaccine hesitancy compared to their peers in upper-middle- and high-income (UMHI) economies (30.4% vs. 19.8%; p < 0.01). CONCLUSIONS: The global acceptance level of dental students for COVID-19 vaccines was suboptimal, and their worrisome level of vaccine hesitancy was influenced by the socioeconomic context where the dental students live and study. The media and social media, public figures, insufficient knowledge about vaccines, and mistrust of governments and the pharmaceutical industry were barriers to vaccination. The findings of this study call for further implementation of epidemiology (infectious diseases) education within undergraduate dental curricula.

7.
Healthcare (Basel) ; 9(4)2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33916358

RESUMEN

The physical closure of higher education institutions due to coronavirus disease 2019 (COVID-19) shed a brighter light on the need to analyze, explore, and implement strategies that allow the development of clinical skills in a distance learning situation. This cross-sectional study aims to assess dental students' self-perception, motivation, organization, acquired clinical skills, and knowledge using the online problem-based learning method, through the application of a 41-item questionnaire to 118 senior students. Answers were subjected to descriptive and inferential statistics analysis. Further, a principal component analysis was performed, in order to examine the factor structure of the questionnaire. Results show that online problem-based learning can be considered a relevant learning tool when utilized within the specific context of clinical dental education, displaying benefits over the traditional learning strategy. Overall, dental students prefer a hybrid system over the conventional one, in a distance learning context, and assume self-responsibility for their own learning, while knowledge thoroughness is perceived as inferior. This online active learning method is successful in improving information and clinical ability (visual/spatial and auditory) advancement in the scope of dental education, with similar results to presential settings. Further studies are required to assess clinical skill development through active learning methods, in a distance learning context.

8.
Clin Linguist Phon ; 35(12): 1113-1131, 2021 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-33412951

RESUMEN

Awake brain surgery, combined with neurophysiological evaluation and intraoperative mapping, is one of the preferential lines of treatment when approaching low-grade gliomas. Speech and language assessment is used while applying Direct Electrical Stimulation (DES) and during the resection of a lesion/tumour, as it allows to establish related eloquent areas and optimise the extent of the resection and avoid impairments. Patients need to be assessed pre, intra and post-surgery, but in under resourced countries such as Portugal, there are still no standardised and validated tools to conduct this type of evaluation. To address this need, the tasks of the Dutch Linguistic Intraoperative Protocol (DuLIP) were adapted to European Portuguese, and the resulting materials were standardised for a group of 144 Portuguese participants. For each task, the impact of age, gender and schooling were measured. The resulting Portuguese version of the DuLIP (DuLIP-EP) consists of 17 tasks, including phonological, syntactic, semantic, naming and articulatory tests. No significant differences were found between male and female participants. However, schooling influenced phonological and syntactic fluency, object naming and verb generation. Schooling and age had a significant impact on semantic fluency and reading with semantic odd word out tasks. This is the first contribution to the standardisation of a tool that can be used during an awake brain surgery in Portugal, which includes a new phonological odd word out task that is not currently available in the Dutch version.


Asunto(s)
Mapeo Encefálico , Vigilia , Encéfalo , Femenino , Humanos , Lingüística , Masculino , Portugal
9.
J Environ Manage ; 279: 111813, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33338770

RESUMEN

Microalgae-bacteria consortium based technology using a High Rate Algal Pond (HRAP) interconnected to an Absorption Bubble Column (ABC) has emerged as an environmentally friendly promising option to upgrade biogas. However, the oxygenic photosynthesis of microalgae induces oxygen contamination in upgraded biogas, which could limit its further applications. Several strategies were proposed to favor the oxygen desorption and oxygen uptake in parts and accessories of the upgrading system. The effect of the volumetric ratio liquid recirculation rate/biogas rate (L/G = 5.0, 1.0 y 0.5) was evaluated in conjunction with the application of a novel accessory called Open Trickling Column (OTC). The O2 content in upgraded biogas was around 2.1%v, attaining CO2 removal efficiencies around 90%, at L/G ratio of 1.0 during diurnal and nocturnal periods. The inclusion of an OTC at the previous L/G, enhanced 54% the removal of O2 by stripping and uptake compared with the basal condition. Mass balances of H2S and methane showed that L/G > 1.0 favored the complete oxidation of H2S but promoted the loss of methane in dissolved form. Additionally the effect of increasing linear velocity of liquid broth in the lab-scale HRAP (from 15 cm s-1 to 20 cm s-1) showed to improve the O2 stripping with a consequential increase of biomass concentration under steady-state (from 0.7 to 1.4 g L-1) besides achieving O2 content in the upgraded biogas around 1.5%v.


Asunto(s)
Microalgas , Biocombustibles , Biomasa , Dióxido de Carbono/análisis , Metano , Oxígeno , Fotobiorreactores , Tecnología
10.
J Clin Med ; 9(7)2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708230

RESUMEN

In this study, we explore the diagnostic accuracy of a Radiographic-based Periodontal Bone Loss (R-PBL) method as a screening tool for periodontitis, in the form of radiographic bone loss, under the 2018 case definition in comparison to the 2012 case definition. The analysis was based on 456 patients (253 females and 203 males), screened for periodontal status in the Study of Periodontal Health in Almada-Seixal (SoPHiAS) project and subjected to a panoramic dental X-ray. Patients were diagnosed for the presence of periodontitis following the 2018 and 2012 case definition. R-PBL classification was defined by alveolar bone loss and diagnosed as no periodontitis (≥80% remaining alveolar bone), mild to moderate periodontitis (66% to 79%), or severe periodontitis (<66%). We appraise the X-ray quality to look for the influence on the performance of R-PBL. Sensitivity, specificity, accuracy, and precision, through several indicators, were determined. Performance measurement was assessed through binary and multiclass Receiver operating characteristic/are under the curve (ROC/AUC) analyses. Our results show that the tested R-PBL method under the 2018 case definition is a reliable tool in periodontitis cases screening. This method does not replace clinical periodontal evaluation, but rather, it screens patients towards a definitive periodontitis diagnosis. These results will contribute to support the development of automated prediction systems towards periodontitis surveillance.

11.
Acta Biomed ; 91(3-S): 85-91, 2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-32275272

RESUMEN

BACKGROUND AND AIM OF THE WORK: The International Health Regulations Emergency Committee declared in 2014 that poliovirus circulation is a public health emergency of international concern. In 2017 and 2018 Italy was classified at intermediate risk of poliovirus reintroduction based on suboptimal poliovirus surveillance. Acute flaccid paralysis active surveillance is the gold standard in the polio eradication process. The aims of this study were to investigate the causes of reduced acute flaccid paralysis case reporting in Emilia-Romagna in the last few years (step 1) and to study a public health intervention to restore an adequate level of acute flaccid paralysis surveillance in that region (step 2). METHODS: In the first step a context analysis was performed by analysing the 2015-2017 Hospital Discharge Registers in Emilia-Romagna with the ICD-9-CM differential diagnosis codes for acute flaccid paralysis. Data from context analysis was then used to plan a new regional collaborative network of acute flaccid paralysis active surveillance. RESULTS: The active surveillance network was, at the end of the study, composed by 49 doctors from both hospital administrations and clinical wards from 4 University Hospitals and 7 Local Health Authorities throughout the Region. In 15 months, 7 acute flaccid paralysis cases have been reported; 85,7% received a full clinical and virological investigation and 83,3% completed the 60 day's follow-up. The mean response to each e-mail was 48,5% (SD 7,5%). CONCLUSIONS: In 2019, the Emilia-Romagna's active surveillance system reached the sensitivity, completeness of case investigation and follow-up required to achieve the minimum levels for certification standard surveillance.


Asunto(s)
Enfermedades Virales del Sistema Nervioso Central/epidemiología , Enfermedades Virales del Sistema Nervioso Central/prevención & control , Mielitis/epidemiología , Mielitis/prevención & control , Enfermedades Neuromusculares/epidemiología , Enfermedades Neuromusculares/prevención & control , Vigilancia de la Población , Niño , Humanos , Italia/epidemiología , Salud Pública
13.
Sci Total Environ ; 667: 613-621, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30833260

RESUMEN

The rates of oxygenic and carbon fixation photosynthetic processes of a microalgae consortium were simultaneously evaluated under steady-state performance in an bench scale alkaline open-system exposed to outdoor conditions in Mexico City. A synthetic methane-free gaseous stream (SMGS) similar to biogas was used as inorganic carbon source and model of biogas upgrading. The microalgae CO2 fixation rates were calculated through a novel methodology based on an inorganic carbon mass balance under continuous scrubbing of a SMGS similar to biogas, where the influence of pH and temperature time-depended oscillations were successfully incorporated into the mass balances. The oxygenic activity and carbon fixation occurred at different non-stoichiometric rates during the diurnal phase, in average carbon fixation predominated over oxygen production (photosynthesis quotient PQ≈ 0.5 mol O2 mol-1 CO2) indicating photorespiration occurrence mainly under dissolved oxygen concentrations higher than 10 mg L-1. The oxygen and inorganic carbon mass balances demonstrated that photorespiration and endogenous respiration were responsible for losing up to 66% and 7% respectively of the biomass grew at diurnal periods under optimal conditions. In favoring photorespiration conditions, the microalgae biomass productivity (CO2 effectively captured) can be severely decreased. A kinetic mathematical model as a function of temperature and irradiance of the oxygenic photosynthetic activity indicated the optimal operation zone for this outdoor alkaline open-photobioreactor, where irradiance was found being the most influential parameter.


Asunto(s)
Biocombustibles , Fotobiorreactores , Fenómenos Bioquímicos , Biomasa , Dióxido de Carbono , Concentración de Iones de Hidrógeno , Cinética , Microalgas , Oxígeno , Fotosíntesis , Temperatura
14.
Sci Total Environ ; 650(Pt 2): 1898-1912, 2019 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-30286356

RESUMEN

Ria de Aveiro represents a coastal territory, in which its natural capital, mostly classified under a Natura 2000 network of protected areas, is of paramount importance for the regional and national economy, supporting harbour activities and maritime traffic, agriculture, commercial fisheries, aquaculture, manufacturing, tourism, sports and recreational activities. Current and foreseen changes connected to human activities, namely land and water uses and potential conflicts, in frame of environmental policies, sustainable economic development and human well-being require the implementation of ecosystem-based management (EBM) planning processes considering the connectivity across marine, transitional, freshwater, and terrestrial domains. The main objective is to elaborate on the co-development of the EBM planning process across the three water domains, all characterized by high biodiversity and by the wide range of services provided by ecosystems and their abiotic components, for the mitigation of impacts from the management plan under implementation. The approach used follows a stepwise procedure in frame of resilience principles, considering the analysis of the relationship between the social and ecological components and on how these can be connected through risk assessment and a spatial multi-criteria analysis based on the delivery of ecosystem services. Stakeholders' perception matched the ecosystem services provisioning risk assessment and supported the planning EBM response that consist in saltmarshes and seagrasses meadows restoration programs. Compliance of the proposed measures is achievable regarding policies (policy targets and policy instruments) and feasibility (scientific and technological knowledge and financial resources). The EBM response can support the Vouga estuary management plan and regional smart specialization (RIS3 Centro).

15.
Sci Total Environ ; 652: 1113-1128, 2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30586798

RESUMEN

The Baixo Vouga Lagunar (BVL) is part of Ria de Aveiro coastal lagoon in Portugal, which is classified as a Special Protection Area under the European Habitats and Birds Directives. This part of the system, corresponding to the confluence of the Vouga River with the lagoon, is very important culturally and socioeconomically for the local communities, taking place several human activities, especially agriculture. To prevent salt water intrusion from the Ria de Aveiro into agriculture fields, a floodbank was initiated in the 90's. In frame of ongoing changes in Ria de Aveiro hydrodynamics, the existing floodbank will be now extended, introducing further changes in the ecological dynamics of the BVL and its adjacent area. As a consequence, the water level in the floodbank downstream side is expected to rise, increasing the submersion period in tidal wetlands, and leading to coastal squeeze. The aim of this study is to apply an ecosystem based-management approach to mitigate the impacts on biodiversity resulting from the management plan. To do so, we have modelled the implications of the changes in several hydrological and environmental variables on four saltmarsh species and habitats distribution, as well as on their associated ecosystem services, both upstream and downstream of the floodbank. The ecosystem services of interest were prioritized by stakeholders' elicitation, which were then used as an input to a spatial multi-criteria analysis aimed to find the best management actions to compensate for the unintended loss of biodiversity and ecosystem services in the BVL. According to our results, the main areas to be preserved in the BVL were the traditional agricultural mosaic fields; the freshwater courses and the subtidal estuarine channels. By combining ecology with the analysis of social preferences, this study shows how co-developed solutions can support adaptive management and the conservation of coastal ecosystems.

18.
Turk J Anaesthesiol Reanim ; 46(3): 222-228, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30140519

RESUMEN

OBJECTIVE: Patients undergoing endovascular aneurysm repair (EVAR) have comorbidities that increase the risk of death, myocardial infarction (MI) and acute kidney injury (AKI). Our aim was to evaluate the incidence and predictors of mortality, MI and AKI after EVAR and to compare AKI incidence with Vascular Surgery Kidney Injury Predictive Score (VSKIPS). METHODS: We conducted a retrospective study of EVAR procedures performed between March 2006 and November 2013. We defined mortality at 30 days, MI as an increase in troponin level to >0.034 ng mL-1 in the first 72 h and AKI as an increase in creatinine level to >0.3 mg dL-1 in the first 48 h after surgery. Risk factors were analysed using logistic regression calculating Hosmer-Lemeshow test and the area under the receiver operating curve (AUROC). RESULTS: Ninety-eight patients were included in the study. The incidence of mortality, MI, and AKI was 2%, 5%, and 18%, respectively. AKI increased the risk of MI [odds ratio (OR) 24.4, p=0.006]. Preoperative serum urea level of >50 mg dL-1 (OR 4.97, p=0.038), general anaesthesia (OR 9.64, p=0.002) and surgery duration (OR 1.53, p=0.043) were considered independent predictors of AKI. The AUROC of the AKI model was 0.886 compared with 0.793 of VSKIPS. CONCLUSION: We found the incidence of mortality, MI and AKI consistent with that of previous studies. However, we may be underestimating the last two because of the short follow-up time. AKI was an independent predictor of MI. Preoperative serum urea level of >50 mg dL-1, general anaesthesia and surgery duration were considered independent predictors of AKI.

19.
Sci Total Environ ; 592: 419-425, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28340452

RESUMEN

Microalgal-bacterial processes have emerged as environmental friendly systems for the cost-effective treatment of anaerobic effluents such as biogas and nutrients-laden digestates. Environmental parameters such as temperature, irradiation, nutrient concentration and pH effect the performance of the systems. In this paper, the potential of a microalgal-bacterial photobioreactor operated under high pH (≈9.5) and high alkalinity to convert biogas into biomethane was evaluated. The influence of the illumination regime (continuous light supply vs 12h/12h light/dark cycles) on the synthetic biogas upgrading efficiency, biomass productivity and nutrient removal efficiency was assessed in a High-Rate Algal Pond interconnected to a biogas absorption bubble column. No significant differences in the removal efficiency of CO2 and H2S (91.5±2% and 99.5%±0.5, respectively) were recorded regardless of the illumination regime. The high fluctuations of the dissolved oxygen concentration during operation under light/dark cycles allowed to evaluate the specific growth rate and the specific partial degradation rate of the microalgae biomass by photosynthesis and respiration, respectively. The respiration reduced the net microalgae biomass productivity under light/dark cycles compared with process operation under the continuous light supply.


Asunto(s)
Biocombustibles , Iluminación , Microalgas/fisiología , Fotosíntesis , Biomasa , Estanques
20.
Sci Rep ; 7: 40795, 2017 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-28098211

RESUMEN

Mapping and quantifying bottom trawling fishing pressure on the seafloor is pivotal to understand its effects on deep-sea benthic habitats. Using data from the Vessel Monitoring System of crustacean trawlers along the Portuguese margin, we have identified the most exploited areas and characterized the most targeted habitats and water depths. We estimated a total trawling effort of 69596, 66766, and 63427 h y-1 for the years 2012, 2013, and 2014 respectively which, considering the total landings estimated for this gear, yield values of 20.76, 21.06, and 19.11 kg of landed fish per trawled hour. The main trawling pressure is exerted in the South and Southwest Portuguese margins, on muddy and muddy-sand bottoms between 200 and 700 m water depths, while in the North and Central-West coasts a minor effort, at shallower waters and across a wider range of habitats, is also applied. The most landed species are crustaceans such as rose shrimp and Norway lobster, although this varies importantly between the different regions of Portugal, being fish and cephalopods the main captures in the Northern ports. We discuss the consequences of trawling for the impacted communities as well as the characteristics of the commercialization of these captures in Portugal.


Asunto(s)
Crustáceos , Ecosistema , Explotaciones Pesqueras , Animales , Demografía , Geografía , Océanos y Mares , Densidad de Población , Portugal
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