scholarly journals Seasonal Photoacclimation and Vulnerability Patterns in the Brown Macroalga Lessonia spicata (Ochrophyta)

Water ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 6
Author(s):  
Antonio Zúñiga ◽  
Claudio A. Sáez ◽  
Andrés Trabal ◽  
Félix L. Figueroa ◽  
Diego Pardo ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Solar Irradiance ◽  
Photosynthetic Pigment ◽  
Thermal Dissipation ◽  
Factors Affecting ◽  
High Solar Radiation ◽  
Activity Measurements ◽  
Total Antioxidant ◽  
One Year ◽  
Brown Macroalga

Fluctuations in solar radiation are one of the key factors affecting productivity and survival in habitat forming coastal macroalgae, in this regard, photoacclimation has a direct impact on the vulnerability and the capacity of seaweed to withstand, for instance, radiation excess. Here, we study ecophysiological responses through photosynthetic activity measurements under time-dependent (one year) fluctuations in solar radiation in the brown macroalga L. spicata. The responses presented seasonal patterns, with an increase in photosynthetic capacity during summer, expressed in greater maximal electron transport rate (ETRmax) and diminished thermal dissipation (NPQmax). Moreover, we studied photoprotective compounds (phenolic compounds) and total antioxidant capacity, which demonstrated an increase during periods of high solar radiation. In addition, content of photosynthetic pigment (Chla, Chlc and Carotenoids) increased under greater solar irradiance. The L. spicata can accumulate as reservoir photoprotective and antioxidant substances to withstand periods of high solar irradiance. All ecophysiological and biochemical responses in L. spicata indicate high photoacclimation and low vulnerability in the species, especially during with greater levels of solar irradiance.

Coronary endarterectomy in coronary artery disease: Factors affecting graft patency and survival

2021 ◽  
pp. 021849232110068
Author(s):  
Simon CY Chow ◽  
Jacky YK Ho ◽  
Micky WT Kwok ◽  
Takuya Fujikawa ◽  
Kevin Lim ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Graft Patency ◽  
Complete Revascularization ◽  
Coronary Endarterectomy ◽  
Factors Affecting ◽  
Early Results ◽  
Cerebrovascular Events ◽  
Obtuse Marginal ◽  
One Year

Background Coronary endarterectomy aims to improve completeness of revascularization in patients with occluded coronary vessels. The benefits of coronary endarterectomy remain uncertain. The aim of this study was to evaluate short-term surgical outcomes and factors affecting graft patency post-coronary endarterectomy. Methods Between 2009 and 2019, 81 consecutive patients who had coronary endarterectomy done were evaluated for their perioperative and early results. A total of 36 patients with follow-up coronary studies were included in patency analysis. Mortality rates, major adverse cardiac and cerebrovascular events, and graft patency were outcomes of interest. Survival and risk factor analysis were performed with Kaplan–Meier and logistic regression analysis. Results The average age of the cohort was 61.9 ± 9.29 years. Complete revascularization rate was 95.4% post-coronary endarterectomy. The 30-day and 1-year mortality was 2.5 and 6.2%, respectively. One-year major adverse cardiac and cerebrovascular events rate was 11.1%. Periprocedural myocardial infarction rate was 7.4%. Three patients required repeat revascularization within a mean follow-up duration of 49.6 ± 36.5 months. Overall graft patency was 89.2% at 20.2 months and graft patency post-coronary endarterectomy was 85.4%. Arterial grafts showed 100% patency. Vein grafts to endarterectomized obtuse marginal branch had patency rates of 33.3%. Multiple endarterectomies were associated with worse one-year major adverse cardiac and cerebrovascular events (OR: 28.6 ± 1.16; P = 0.003). Conclusions Coronary endarterectomy facilitates completeness of revascularization and does not increase early mortality. Graft patency post-coronary endarterectomy on obtuse marginal artery was suboptimal. Judicious use of coronary endarterectomy should be practiced to balance the need of completeness of revascularization against the risk of myocardial infarction.

scholarly journals Calibration and Validation of ArcGIS Solar Radiation Tool for Photovoltaic Potential Determination in the Netherlands

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1865
Author(s):  
Bala Bhavya Kausika ◽  
Wilfried G. J. H. M. van Sark
Keyword(s):  
Solar Radiation ◽  
The Netherlands ◽  
Urban Areas ◽  
Input Data ◽  
Solar Irradiation ◽  
Energy Yield ◽  
Atmospheric Parameters ◽  
Factors Affecting ◽  
Calibration And Validation ◽  
Solar Radiation Model

Geographic information system (GIS) based tools have become popular for solar photovoltaic (PV) potential estimations, especially in urban areas. There are readily available tools for the mapping and estimation of solar irradiation that give results with the click of a button. Although these tools capture the complexities of the urban environment, they often miss the more important atmospheric parameters that determine the irradiation and potential estimations. Therefore, validation of these models is necessary for accurate potential energy yield and capacity estimations. This paper demonstrates the calibration and validation of the solar radiation model developed by Fu and Rich, employed within ArcGIS, with a focus on the input atmospheric parameters, diffusivity and transmissivity for the Netherlands. In addition, factors affecting the model’s performance with respect to the resolution of the input data were studied. Data were calibrated using ground measurements from Royal Netherlands Meteorological Institute (KNMI) stations in the Netherlands and validated with the station data from Cabauw. The results show that the default model values of diffusivity and transmissivity lead to substantial underestimation or overestimation of solar insolation. In addition, this paper also shows that calibration can be performed at different time scales depending on the purpose and spatial resolution of the input data.

scholarly journals Exacerbations and Changes in Physical Activity and Sedentary Behaviour in Patients with Bronchiectasis after 1 Year

2021 ◽  
Vol 10 (6) ◽  
pp. 1190
Author(s):  
Victoria Alcaraz-Serrano ◽  
Ane Arbillaga-Etxarri ◽  
Patricia Oscanoa ◽  
Laia Fernández-Barat ◽  
Leticia Bueno ◽  
...  
Keyword(s):  
Physical Activity ◽  
Sedentary Behaviour ◽  
Prospective Observational Study ◽  
Multivariable Analysis ◽  
Sensewear Armband ◽  
Activity Measurements ◽  
Key Factor ◽  
Steps Per Day ◽  
One Year

Background: Low physical activity and high sedentary behaviour in patients with bronchiectasis are associated with hospitalisation over one year. However, the factors associated with longitudinal changes in physical activity and sedentary behaviour have not been explored. We aimed to identify clinical and sociodemographic characteristics related to a change in physical activity and sedentary behaviour in patients with bronchiectasis after one year. Methods: This was a prospective observational study during which physical activity measurements were recorded using a SenseWear Armband for one week at baseline and at one year. At each assessment point, patients were classified as active or inactive (measured as steps per day) and as sedentary or not sedentary (measured as sedentary time). Results: 53 patients with bronchiectasis were analysed, and after one year, 18 (34%) had worse activity and sedentary levels. Specifically, 10 patients became inactive and sedentary. Multivariable analysis showed that the number of exacerbations during the follow-up period was the only outcome independently associated with change to higher inactivity and sedentary behaviour (odds ratio (OR), 2.19; 95% CI, 1.12 to 4.28). Conclusions: The number of exacerbations in patients with bronchiectasis was associated with changes in physical activity and sedentary behaviour. Exacerbation prevention may appear as a key factor in relation to physical activity and sedentary behaviour in patients with bronchiectasis.

Analysis of Single-Vehicle Crash Injury Severities in Urban River-Crossing Road Tunnels

2015 ◽  
Vol 743 ◽  
pp. 526-532 ◽  
Author(s):  
C.M. Jiang ◽  
J.J. Lu ◽  
L.J. Lu
Keyword(s):  
Heavy Vehicles ◽  
Probit Regression ◽  
Factors Affecting ◽  
Explanatory Variables ◽  
Urban Road ◽  
Road Tunnels ◽  
Negative Effect ◽  
Single Vehicle ◽  
Injury Severities ◽  
One Year

Based on the originally unprocessed data from the Official Platform of“110”Alarming Receiving Center (OP110ARC) of Shanghai Public Security Bureau (SPSB), 529 single-vehicle crashes reported during one year and a half which happened at the thirteen urban road tunnels going across the Huangpu River are used in this study. To investigate the factors affecting the crash influence severity levels, ordered probit regression is established. Several categories of factors are considered as explanatory variables in the models. The study finds that the entrance of the tunnels is the site where severe injury crashes trend to occur. Rainy and snowy days impose vehicles and motorists driving via the tunnel sections in danger. Tunnels with a low speed limit (40 km/h in this study) may be not as safe as we thought before. Two-wheel vehicles without sufficient physical protection for its drivers and heavy vehicles also show a negative effect on the operation safety of single-vehicle at these studied tunnels. Alcohol involved drivers are more likely to suffer from a severe crashes and gets badly hurt.

scholarly journals Thermal comfort in winter incorporating solar radiation effects at high altitudes and performance of improved passive solar design—Case of Lhasa

2020 ◽  
Author(s):  
Lingjiang Huang ◽  
Jian Kang
Keyword(s):  
Solar Radiation ◽  
Thermal Comfort ◽  
Energy Saving ◽  
Solar Irradiance ◽  
Indoor Environment ◽  
Thermal Mass ◽  
High Altitudes ◽  
Energy Saving Potential ◽  
Environment Control ◽  
Passive Solar

AbstractThe solar incidence on an indoor environment and its occupants has significant impacts on indoor thermal comfort. It can bring favorable passive solar heating and can result in undesired overheating (even in winter). This problem becomes more critical for high altitudes with high intensity of solar irradiance, while received limited attention. In this study, we explored the specific overheating and rising thermal discomfort in winter in Lhasa as a typical location of a cold climate at high altitudes. First, we evaluated the thermal comfort incorporating solar radiation effect in winter by field measurements. Subsequently, we investigated local occupant adaptive responses (considering the impact of direct solar irradiance). This was followed by a simulation study of assessment of annual based thermal comfort and the effect on energy-saving potential by current solar adjustment. Finally, we discussed winter shading design for high altitudes for both solar shading and passive solar use at high altitudes, and evaluated thermal mass shading with solar louvers in terms of indoor environment control. The results reveal that considerable indoor overheating occurs during the whole winter season instead of summer in Lhasa, with over two-thirds of daytime beyond the comfort range. Further, various adaptive behaviors are adopted by occupants in response to overheating due to the solar radiation. Moreover, it is found that the energy-saving potential might be overestimated by 1.9 times with current window to wall ratio requirements in local design standards and building codes due to the thermal adaption by drawing curtains. The developed thermal mass shading is efficient in achieving an improved indoor thermal environment by reducing overheating time to an average of 62.2% during the winter and a corresponding increase of comfort time.

Obtainable Method of Measuring the Solar Radiant Flux Based on Silicone Photodiode Element

2016 ◽  
Vol 824 ◽  
pp. 477-484 ◽  
Author(s):  
Miroslav Čekon ◽  
Richard Slávik ◽  
Peter Juras
Keyword(s):  
Solar Radiation ◽  
Solar Irradiance ◽  
Climate Science ◽  
Radiant Flux ◽  
Silicon Photodiode ◽  
Building Science ◽  
Solar Instruments ◽  
Solar Radiation Exposure ◽  
Building Physics

Solar radiation exposure and its monitoring does have not only the importance for climate science and meteorology however is equally of highly relevant use for the field of Building Science as primarily those of analyzing thermal aspects in building physics. Here the measuring of solar irradiance by means of well-established solar instruments can be applied whose advances have been undergoing steep progress. Currently, a silicon photodiode element, as a truly obtainable form, may have a feasible exploitation in the field of building applications concerning the solar radiant flux quantifying. It represents a small optoelectronic element and has a several exploitable advantages. The paper presents a perspective alternative to monitor solar irradiance. Own measurement assembly is proposed and introduced. Initial in-situ measurements are performed and final comparability with existing commercial solar instruments is presented. An obtained correlation with existing types demonstrates its applicability to the field of building science and solar energy.

scholarly journals The Potential of Solar Air Heating in the Turkish Industrial Sector

2018 ◽  
Vol 63 (1) ◽  
pp. 57-66
Author(s):  
Balázs Bokor ◽  
Hacer Akhan ◽  
Dogan Eryener ◽  
László Kajtár
Keyword(s):  
Solar Radiation ◽  
Energy Savings ◽  
Measurement Data ◽  
Industrial Sector ◽  
Climatic Conditions ◽  
Cold Climate ◽  
Conventional Heating ◽  
Industrial Building ◽  
High Solar Radiation ◽  
Mathematical Correlation

Transpired solar collector (TSC) systems are simple solutions for the preheating of ventilation air with solar energy. Their performance is a function of several environmental factors, so the climatic conditions of the location play an important role. In this paper, the effect of different climatic zones on the thermal performance of the TSC is investigated. To exclude other sources of influence, the same reference industrial building is examined in four Turkish locations (Antalya, Istanbul, Ankara and Sivas) representing different climatic conditions. RETScreen simulation is carried out for all four regions to obtain the drop of conventional heating requirement in case absorber azimuth of 0°, 45° and 90°. To illustrate the performance, temperature rise, heating energy savings and annual solar fraction are presented. Generally, it can be stated that a location with cold climate and high solar radiation at the same time benefits most from the use of a TSC system. A mathematical correlation has been found showing the solar fraction's dependence on solar radiation and heating degree days. Finally, simulation results have been compared to a set of measurement data from an industrial building's TSC system near Istanbul.

scholarly journals Exposure to high solar radiation reduces self-regulated exercise intensity in the heat outdoors

2019 ◽  
Vol 199 ◽  
pp. 191-199 ◽  
Author(s):  
Hidenori Otani ◽  
Mitsuharu Kaya ◽  
Akira Tamaki ◽  
Heita Goto ◽  
Ronald J. Maughan
Keyword(s):  
Solar Radiation ◽  
Exercise Intensity ◽  
High Solar Radiation

scholarly journals Epilithic community development on artificial reefs deployed along a cross-shelf environmental gradient off Paraná state, southern Brazil

2011 ◽  
Vol 59 (spe1) ◽  
pp. 43-53 ◽  
Author(s):  
Frederico Brandini ◽  
Ariel Scheffer da Silva
Keyword(s):  
Large Scale ◽  
Diversity Index ◽  
Artificial Reef ◽  
Larval Abundance ◽  
Percent Cover ◽  
Southern Brazil ◽  
Factors Affecting ◽  
Hydrographic Conditions ◽  
One Year ◽  
General Community

Concrete modules were deployed on the bottom of the 11, 18 and 30 meters isobaths along a cross-shelf hydrographic gradient off Paraná State, Southern Brazil, with the purpose of studying the colonization of sessile epilithic macroinvertebrates on artificial surfaces. After one year of submersion a total of 63 species of epilithic organisms were identified, dominated by Ostrea puelchana, Chthamalus bisinuatus, Balanus cf spongicola, Astrangia cf rathbuni, Didemnum spp, poryphers and bryozoans. Diversity index and percent cover at reef stations placed at 11, 18 and 30 meters isobaths were respectively 2.28 and 66.7%, 2.79 and 96.6% and 1.66 and 77.4%. Differences of general community structure among the three assemblages were not clearly related to the general environmental conditions at the bottom layers near the reef stations. Turbidity and larval abundance are discussed as important factors affecting colonization processes. Results indicate that depths between 15-20 meters are more suitable for the implementation of large scale artificial reef systems in the inner shelf off Paraná and, possibly, throughout the inner shelves off southern Brazil with similar hydrographic conditions.

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