scholarly journals Vegetative Reproduction Is More Advantageous Than Sexual Reproduction in a Canopy-Forming Clonal Macroalga under Ocean Warming Accompanied by Oligotrophication and Intensive Herbivory

Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1522
Author(s):  
Hikaru Endo ◽  
Toru Sugie ◽  
Yukiko Yonemori ◽  
Yuki Nishikido ◽  
Hikari Moriyama ◽  
...  
Keyword(s):  
Growth Rate ◽  
High Temperature ◽  
Nutrient Availability ◽  
Vegetative Reproduction ◽  
Ocean Warming ◽  
Regeneration Ability ◽  
Combined Effects ◽  
Regeneration Rate ◽  
Fish Herbivory ◽  
C 30

Ocean warming and the associated changes in fish herbivory have caused polarward distributional shifts in the majority of canopy-forming macroalgae that are dominant in temperate Japan, but have little effect on the alga Sargassum fusiforme. The regeneration ability of new shoots from holdfasts in this species may be advantageous in highly grazed environments. However, little is known about the factors regulating this in Sargassum species. Moreover, holdfast tolerance to high-temperature and nutrient-poor conditions during summer has rarely been evaluated. In the present study, S. fusiforme holdfast responses to the combined effects of temperature and nutrient availability were compared to those of sexually reproduced propagules. The combined effects of holdfast fragmentation and irradiance on regeneration were also evaluated. Propagule growth rate values changed from positive to negative under the combination of elevated temperature (20 °C–30 °C) and reduced nutrient availability, whereas holdfasts exhibited a positive growth rate even at 32 °C in nutrient-poor conditions. The regeneration rate increased with holdfast fragmentation (1 mm segments), but was unaffected by decreased irradiance. These results suggest that S. fusiforme holdfasts have a higher tolerance to high-temperature and nutrient-poor conditions during summer than propagules, and regenerate new shoots even if 1-mm segments remain in shaded refuges for fish herbivory avoidance.

scholarly journals Combined effects of elevated <i>p</i>CO<sub>2</sub> and temperature on biomass and carbon fixation of phytoplankton assemblages in the northern South China Sea

2016 ◽  
Author(s):  
Guang Gao ◽  
Peng Jin ◽  
Nana Liu ◽  
Futian Li ◽  
Shanying Tong ◽  
...  
Keyword(s):  
High Temperature ◽  
South China Sea ◽  
Dark Respiration ◽  
Northern South China Sea ◽  
Ocean Warming ◽  
Combined Effects ◽  
Dark Respiration Rate ◽  
Phytoplankton Assemblages ◽  
Chl A ◽  
Phytoplankton Communities

Abstract. The individual influences of ocean warming and acidification on marine organisms have been investigated intensively, but studies regarding the combined effects of both global change variables on natural marine phytoplankton assemblages are still scarce. Even fewer studies have addressed possible differences in the responses of phytoplankton communities in pelagic and coastal zones to ocean warming and acidification. We conducted shipboard microcosm experiments at both off-shore (SEATS) and near-shore (D001) stations in the northern South China Sea (NSCS) under three treatments, low temperature (30.5 °C at SEATS and 28.5 °C at D001) and low pCO2 (390.0 µatm at SEATS and 420.0 µatm at D001) (LTLC), high temperature (33.5 °C at SEATS and 31.5 °C at D001) and low pCO2 (390 µatm at SEATS and 420 µatm at D001) (HTLC), and high temperature (33.5 °C at SEATS and 31.5 °C at D001) and high pCO2 (1000 µatm at SEATS and 1030 µatm at D001) (HTHC). Biomass of phytoplankton at both stations were enhanced by HT. HTHC did not affect phytoplankton biomass at station D001 but decreased it at station SEATS. At this offshore station HT alone increased daily primary productivity (DPP, µgC (µg chl a)−1 d−1) by ~ 64 %, and by ~ 117 % when higher pCO2 was added. In contrast, HT alone did not affect DPP and HTHC reduced it by ~ 15 % at station D001. HT enhanced the dark respiration rate (µg C (µg chl a)-1 d−1) by 64 % at station SEATS, but had no significant effect at station D001, and did not change the ratio of respiration to photosynthesis at either station. HTHC did not affect dark respiration rate (µg C (µg chl a)−1 d−1) at either station compared to LTLC. HTHC reduced the respiration to photosynthesis ratio by ~ 41 % at station SEATS but increased it ~ 42 % at station D001. Overall, our findings indicate that responses of coastal and offshore phytoplankton assemblages in NSCS to ocean warming and acidification are contrasting, with the pelagic phytoplankton communities being more sensitive to these two global change factors.

scholarly journals High-Temperature Short-Time and Holder Pasteurization of Donor Milk: Impact on Milk Composition

Life ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 114
Author(s):  
Diana Escuder-Vieco ◽  
Juan M. Rodríguez ◽  
Irene Espinosa-Martos ◽  
Nieves Corzo ◽  
Antonia Montilla ◽  
...  
Keyword(s):  
High Temperature ◽  
Human Milk ◽  
Milk Composition ◽  
Donor Human Milk ◽  
High Temperature Short Time ◽  
Lactose Concentration ◽  
C 30 ◽  
Milk Banks ◽  
Short Time

Holder pasteurization (HoP; 62.5 °C, 30 min) is commonly used to ensure the microbiological safety of donor human milk (DHM) but diminishes its nutritional properties. A high-temperature short-time (HTST) system was designed as an alternative for human milk banks. The objective of this study was to evaluate the effect of this HTST system on different nutrients and the bile salt stimulated lipase (BSSL) activity of DHM. DHM was processed in the HTST system and by standard HoP. Macronutrients were measured with a mid-infrared analyzer. Lactose, glucose, myo-inositol, vitamins and lipids were assayed using chromatographic techniques. BSSL activity was determined using a kit. The duration of HTST treatment had a greater influence on the nutrient composition of DHM than did the tested temperature. The lactose concentration and the percentage of phospholipids and PUFAs were higher in HTST-treated than in raw DHM, while the fat concentration and the percentage of monoacylglycerides and SFAs were lower. Other nutrients did not change after HTST processing. The retained BSSL activity was higher after short HTST treatment than that following HoP. Overall, HTST treatment resulted in better preservation of the nutritional quality of DHM than HoP because relevant thermosensitive components (phospholipids, PUFAs, and BSSL) were less affected.

High temperature growth rate in MOCVD growth of AlGaAs

1984 ◽  
Vol 68 (1) ◽  
pp. 169-175 ◽  
Author(s):  
Tetsuo Soga ◽  
Yasuhito Takahashi ◽  
Shiro Sakai ◽  
Masayoshi Umeno
Keyword(s):  
Growth Rate ◽  
High Temperature ◽  
Temperature Growth ◽  
Mocvd Growth

scholarly journals Ultra-High Temperature Effect on Bioactive Compounds and Sensory Attributes of Orange Juice Compared with Traditional Processing

2017 ◽  
Vol 71 (6) ◽  
pp. 486-491
Author(s):  
Gaļina Zvaigzne ◽  
Daina Kārkliņa ◽  
Joerg-Thomas Moersel ◽  
Sasha Kuehn ◽  
Inta Krasnova ◽  
...  
Keyword(s):  
High Temperature ◽  
Vitamin C ◽  
Bioactive Compounds ◽  
Orange Juice ◽  
Sensory Attributes ◽  
Heat Treated ◽  
C 30 ◽  
Traditional Processing ◽  
The Impact ◽  
Ultra High Temperature

Abstract Orange juices are an important source of bioactive compounds. Because of its unique combination of sensory attributes and nutritional value, orange juice is the world’s most popular fruit juice. Orange (Citrus sinensis) juice of Greek Navel variety was used in this study. The impact of Conventional Thermal Pasteurisation (94 °C/30') (CTP) and alternative Ultra-High Temperature (UHT) (130 °C/2') processing on bioactive compounds and antioxidant capacity changes of fresh Navel orange juice was investigated. Sensory attributes of processed juices were evaluated. Results showed that using technologies CTP and UHT orange juice Navel significantly changed vitamin C concentration in comparison with fresh orange juice. The highest concentration of antioxidants (vitamin C, total phenols, hesperidin and carotenoids) was observed in orange juice Navel produced by UHT technology. Sensory results indicated that characteristics of the orange juice obtained using UHT technology were more liked than the CTP heat treated juice. UHT technology emerges as an advantageous alternative process to preserve bioactive compounds in orange juice.

Scatter in Dwell Time Cracking for a Ni-Based Superalloy in Combination With Overloads

2015 ◽  
Author(s):  
Erik Storgärds ◽  
Jonas Saarimäki ◽  
Kjell Simonsson ◽  
Sören Sjöström ◽  
David Gustafsson ◽  
...  
Keyword(s):  
Growth Rate ◽  
High Temperature ◽  
Crack Growth ◽  
Material Properties ◽  
Inconel 718 ◽  
Dwell Time ◽  
The Other ◽  
Surface Cracks ◽  
Multiple Tests ◽  
Material Data

In this paper scatter in crack growth for dwell time loadings in combination with overloads has been investigated. Multiple tests were performed for surface cracks at 550°C in the commonly used high temperature material Inconel 718. The test specimens originate from two different batches which also provides for a discussion of how material properties affect the dwell time damage and overload impact. In combination with these tests an investigation of the microstructure was also carried out, which shows how it influences the growth rate. The results from this study show that, in order to take overloads into consideration when analysing spectrum loadings containing dwell times, one needs a substantial amount of material data available as the scatter seen from one batch to the other is of significant proportions.

Numerical investigation of induced thermal impacts from high-temperature thermal energy storage in porous aquifers

2021 ◽  
Author(s):  
Bo Wang ◽  
Jens-Olaf Delfs ◽  
Christof Beyer ◽  
Sebastian Bauer
Keyword(s):  
High Temperature ◽  
Energy Storage ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Storage Capacity ◽  
Storage Temperature ◽  
Thermal Recovery ◽  
Pumping Rate ◽  
Background Temperature ◽  
C 30

&lt;p&gt;High-temperature aquifer thermal energy storage (HT-ATES) in the geological subsurface will affect the temperature distribution in and close to the storage site, with potential impacts on groundwater flow and biogeochemistry. Quantification of the subsurface space affected by a HT-ATES operation is thus required as one basis for urban subsurface space planning, which would allow to address potential competitive and conflicting uses of the urban subsurface. Therefore, this study shows a quantitative evaluation of induced thermal impacts and subsurface space required for a synthetic ATES operated at varying temperature levels.&lt;/p&gt;&lt;p&gt;A hypothetic seasonal HT-ATES operation is simulated using the coupled groundwater flow and heat transport code OpenGeoSys. A well doublet system consisting of fully screened &amp;#8220;warm&amp;#8221; and &amp;#8220;cold&amp;#8221; wells 500 m apart is used for the storage operation. A sandy aquifer typical for the North German Basin at a depth of 110 m and with a thickness of 20 m in between two confining impermeable layers is used as storage formation. Seasonal cyclic storage is simulated for 20 years, assuming charging and discharging for six months each. During charging, water with the aquifer background temperature of 13&amp;#176;C is extracted at the &quot;cold&quot; well, heated to 70&amp;#176;C and reinjected at the &amp;#8220;warm&amp;#8221; well using a pumping rate of 30 m&amp;#179;/h. During discharging, the stored hot water is retrieved at the &quot;warm&quot; well using the same pumping rate and reinjected at the &amp;#8220;cold&amp;#8221; well after heat extraction at aquifer background temperature.&lt;/p&gt;&lt;p&gt;The simulation results show that during a single storage cycle using a storage temperature of 70&amp;#176;C 7.51 GWh of thermal energy is injected, of which 4.79 GWh can be retrieved. This corresponds to a thermal recovery factor of 63.8% and thus an effective storage capacity of 0.43&amp;#160;kWh/m&lt;sup&gt;3&lt;/sup&gt;/K can be deduced in relation to the heat capacity of the storage medium. For storage temperatures of 18&amp;#176;C, 30&amp;#176;C and 50&amp;#176;C, the effective storage capacity is 0.56 kWh/m&lt;sup&gt;3&lt;/sup&gt;/K, 0.55 kWh/m&lt;sup&gt;3&lt;/sup&gt;/K and 0.49 kWh/m&lt;sup&gt;3&lt;/sup&gt;/K, respectively. By delineating the subsurface volume with a temperature increase larger than 1&amp;#176;C, the subsurface space used for and affected by the storage operation at the storage temperature of 70 &amp;#176;C is determined to be 10.56 million m&amp;#179;. In relation to the retrieved thermal energy, a subsurface volume of 2.2 m&lt;sup&gt;3 &lt;/sup&gt;is thus required to retrieve one kWh of heat energy at 70 &amp;#176;C injection temperature. At lower temperatures of 18&amp;#176;C, 30&amp;#176;C and 50&amp;#176;C, the subsurface space required is 1.77 m&lt;sup&gt;3&lt;/sup&gt;/kWh, 1.54 m&lt;sup&gt;3&lt;/sup&gt;/kWh and 1.76 m&lt;sup&gt;3&lt;/sup&gt;/kWh, respectively. The lower effective storage capacity and the relatively larger required space, which correspond to a lower thermal recovery factor, are caused by induced thermal convection and higher heat losses by conduction at higher temperatures.&lt;/p&gt;

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