scholarly journals Rapid and Positive Effect of Bicarbonate Addition on Growth and Photosynthetic Efficiency of the Green Microalgae Chlorella Sorokiniana (Chlorophyta, Trebouxiophyceae)

2020 ◽  
Vol 10 (13) ◽  
pp. 4515 ◽  
Author(s):  
Giovanna Salbitani ◽  
Francesco Bolinesi ◽  
Mario Affuso ◽  
Federica Carraturo ◽  
Olga Mangoni ◽  
...  
Keyword(s):  
Photosynthetic Efficiency ◽  
Inorganic Carbon ◽  
Primary Source ◽  
Photosynthetic Performance ◽  
Chlorella Sorokiniana ◽  
Algal Culture ◽  
Short Term ◽  
Bicarbonate Ions ◽  
Short Period ◽  
Positive Effect

Bicarbonate ions are the primary source of inorganic carbon for autotrophic organisms living in aquatic environments. In the present study, we evaluated the short-term (hours) effects of sodium bicarbonate (NaHCO3) addition on the growth and photosynthetic efficiency of the green algae Chlorella sorokiniana (211/8k). Bicarbonate was added to nonaxenic cultures at concentrations of 1, 2, and 3 g L−1 leading to a significant increase in biomass especially at the highest salt concentration (3 g L−1) and also showing a bactericidal and bacteriostatic effect that helped to keep a reduced microbial load in the algal culture. Furthermore, bicarbonate stimulated the increase in cellular content of chlorophyll a, improving the photosynthetic performance of cells. Since microalgae of genus Chlorella spp. show great industrial potential for the production of biofuels, nutraceuticals, cosmetics, health, and dietary supplements and the use of bicarbonate as a source of inorganic carbon led to short-term responses in Chlorella sorokiniana, this method represents a valid alternative not only to the insufflation of carbon dioxide for the intensive cultures but also for the production of potentially bioactive compounds in a short period.

scholarly journals The effect of tax revenues on GDP growth in Jordan

Accounting ◽  
2021 ◽  
pp. 655-660 ◽  
Author(s):  
Khaled Abdalla Moh'd AL-Tamimi ◽  
Ashraf Bataineh
Keyword(s):  
Primary Source ◽  
Tax Law ◽  
Short Term ◽  
Tax Revenues ◽  
Tax Exemptions ◽  
Technological Means ◽  
The Impact ◽  
The Relationship ◽  
Positive Effect

The research aims to identify the impact of tax revenues on the growth of the gross domestic product (GDP) in Jordan during the period 2000-2018. The research reaches a set of results, which is that the greater the value of tax revenues by one unit, the greater the value of the GDP in Jordan by 7.257 units during the same period. There is also a positive effect of tax revenues on the growth and increase of the GDP in Jordan, however, there is no common integration between tax revenues and the GDP in Jordan. Moreover, there is a correction from the short term to the long term and there is an effect of the long-term correction of the relationship between tax revenues and the GDP during the study period. The study recommends the need to work to facilitate the procedures for individuals to pay taxes through modern technological means, work to develop and simplify tax services and raise the level of transparency in tax dealings with all individuals, the need to make amendments to the tax law in order to match the living conditions of individuals and achieve the highest efficiency in collecting due taxes, increasing tax exemptions that are offered to foreign investment to encourage them for investments in all economic, commercial, service and industrial fields in Jordan, working to diversify sources of income for the Jordanian economy and not to rely entirely on tax revenues as a primary source of income.

Effect of Encrusting Bryozoans on the Physiology of Their Algal Substratum

1991 ◽  
Vol 71 (4) ◽  
pp. 877-882 ◽  
Author(s):  
Jorge Muñoz ◽  
Juan M. Cancino ◽  
MarÍa X. Molina
Keyword(s):  
Photosynthetic Efficiency ◽  
Inorganic Carbon ◽  
Detrimental Effect ◽  
Incident Light ◽  
Benthic Algae ◽  
Photosynthetic Performance ◽  
Photon Flux ◽  
Photon Flux Density ◽  
P Value ◽  
Compensatory Effect

Traditionally, colonies of encrusting epiphytic bryozoans have been regarded as biotic factors reducing photosynthetic performance in benthic algae. In this study we determined under laboratory conditions the effects of Membranipora tuberculata on the photosynthetic efficiency of the rhodophyte Gelidium rex.Encrusting bryozoans reduce to 44% the incident light reaching the algal thallus. However, concentrations of chlorophyll a and other accessory pigments are significantly higher in encrusted than in non-encrusted thalli. Consequently, photosynthetic efficiency is almost identical in both types of thalli. Although non-encrusted thalli showed a higher photosynthetic V due to higher levels of light reaching the algae, encrusted thalli exhibited a compensatory effect at low photon flux density and reached a similar P value. The detrimental effect of M. tuberculata on photosynthesis could be partially compensated by CO released from bryozoan cells, as G. rex preferred CO over HCO3 as a source of photosynthetic inorganic carbon. These results suggest that physiological interaction between bryozoans and algae, involving the interchange of metabolic substances, are likely to be important.

Pengaruh Investasi Asset Jangka Pendek Dan Aktiva Terhadap Laba Usaha Pada Pt. Taspen (Persero)

2018 ◽  
Vol 1 (1) ◽  
pp. 21
Author(s):  
Ilyas Lamuda
Keyword(s):  
Return On Investment ◽  
Quantitative Methods ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Rate Of Return ◽  
Short Term ◽  
Descriptive Data ◽  
Short Term Investment ◽  
Accounting Rate ◽  
Positive Effect

This study was to determine the effect of Short-Term Investments and Assets Assets in generating profits in the company PT. Taspen. The method of analysis used qualitative methods That is explained and analyzed by descriptive data. Quantitative methods to study whether the Short-term investment is profitable or not, can be determined either by the method Accounting Rate Of Return (ARR) That method that measures the level of profit from investments used to gain tersebut.dan the return on investment assets at PT. Taspen. To test the hypothesis then performed calculations using multiple linear regression analysis. Furthermore pengelohan data and hypothesis testing will be assisted by a computer program Softwere SPSS (Statistical Service and Solution product).Research shows that variable Short Term Asset Investments concluded that simultaneous effect relationship is negative and insignificant. But in partial, it provides a significant and positive effect on earnings. Assets Investments variable and not significant positive effect on earnings, but in partial, it provides a significant and positive effect on earnings.

scholarly journals Achieving Efficient and Stable Deammonification at LowTemperatures—Experimental and Modeling Studies

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3961
Author(s):  
Hussein Al-Hazmi ◽  
Xi Lu ◽  
Dominika Grubba ◽  
Joanna Majtacz ◽  
Przemysław Kowal ◽  
...  
Keyword(s):  
Sequencing Batch Reactor ◽  
Energy Savings ◽  
Batch Reactor ◽  
Phase Changes ◽  
Intermittent Aeration ◽  
Short Term ◽  
Higher Temperature ◽  
Effects Of Temperature ◽  
The Mathematical Model ◽  
Positive Effect

The short-term effects of temperature on deammonification sludge were evaluated in a laboratory-scale sequencing batch reactor (SBR). Mathematical modeling was used for further evaluations of different intermittent aeration strategies for achieving high and stable deammonification performance at decreasing temperatures. As for the biomass cultivated at high temperatures (e.g., 30 °C), a higher temperature dependency (the adjusted Arrhenius coefficient θ for 11–17 °C = 1.71 vs. θ for 17–30 °C = 1.12) on the specific anammox growth rates was found at lower temperatures (11–17 °C) in comparison with higher temperatures (17–30 °C). Further evaluations of recovering the nitrogen removal efficiency at decreasing temperatures with the mathematical model by modifying the intermittent aeration strategies (aeration frequency (F) and the ratio (R) between non-aerated (non-aer) phase and aerated (aer) phase durations) indicated that intermittent aeration with a prolonged non-aerated phase (e.g., R ≥ 4 regardless of F value) would help to maintain high and stable deammonification performance (~80%) at decreasing temperatures (14–22 °C). Extending the non-aerated phases (increasing R) and reducing the frequency (F) of off/on phase changes have a positive effect on increasing energy savings, leading to increasing interest in this method.

scholarly journals Effects of different returning method combined with decomposer on decomposition of organic components of straw and soil fertility

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiao Wang ◽  
Xuexin Wang ◽  
Peng Geng ◽  
Qian Yang ◽  
Kun Chen ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Soil Fertility ◽  
Decomposition Rate ◽  
Microbial Biomass Carbon ◽  
No Tillage ◽  
Short Term ◽  
Straw Decomposition ◽  
Short Period ◽  
Straw Return ◽  
Forms Of Carbon

AbstractIn view of the problems of low straw decomposition rates and reduced soil fertility in southern Liaoning, China, we investigated the effects of no-tillage mode (NT), deep loosening + deep rotary tillage mode (PT), rotary tillage mode (RT) and the addition of decomposing agent (the next is called a decomposer) (NT + S, PT + S, RT + S) on the decomposition proportion of straw, respectively, by using the nylon net bag method in combination with 365-day field plot experiments. The decomposition rules of cellulose, hemicellulose and lignin as well as the dynamics of soil organic carbon (SOC), soil microbial biomass carbon (MBC) and soil dissolved organic carbon (DOC) in straw returned to the field for 15, 35, 55, 75, 95, 145 and 365 days were analyzed. The results showed that in the short term, the decomposition of straw was better in both the rotray tillage and deep loosening + deep rotary modes than in the no-tillage mode, and the addition of decomposer significantly promoted the decomposition of straw and the release of carbon from straw, among them, the RT + S treatment had the highest straw decomposition proportion and carbon release proportion in all sampling periods. After a one year experimental cycle, the RT + S treatment showed the highest proportion of cellulose, hemicellulose and lignin decomposition with 35.49%, 84.23% and 85.50%, respectively, and soil SOC, MBC and DOC contents were also higher than the other treatments with an increase of 2.30 g kg−1, 14.22 mg kg−1 and 25.10 mg kg−1, respectively, compared to the pre-experimental soil. Our results show that in the short term, to accelerate the decomposition rate of returned straw and increase the content of various forms of carbon in soil, rotary tillage can be used to return the straw to the field, while also spraying straw decomposer on its surface. This experiment used a new straw decomposer rich in a variety of microorganisms, combined with the comparison of a variety of straw return modes, and in-depth study of straw decomposition effects of cellulose, hemicellulose and lignin. Thus, a scheme that can effectively improve the decomposition rate of straw and the content of various forms of organic carbon in soil within a short period of time was explored to provide theoretical support for the southern Liaoning.

EXPRESS: Short-term upper limb immobilization impairs grasp representation

2020 ◽  
pp. 174702182098552
Author(s):  
Lucette Toussaint ◽  
Aurore Meugnot ◽  
Christel Bidet-Ildei
Keyword(s):  
Response Times ◽  
Motor Program ◽  
Control Group ◽  
Short Term ◽  
Small Sphere ◽  
Large Sphere ◽  
Short Period ◽  
Limb Immobilization ◽  
Laterality Task ◽  
Sensorimotor Processes

The present experiment aimed to gain more information on the effect of limb nonuse on the cognitive level of actions and, more specifically, on the content of the motor program used for grasping an object. For that purpose, we used a hand-grasping laterality task that is known to contain concrete information on manipulation activity. Two groups participated in the experiment: an immobilized group, including participants whose right hand and arm were fixed with a rigid splint and an immobilization vest for 24 hours, and a control group, including participants who did not undergo the immobilization procedure. The main results confirmed a slowdown of sensorimotor processes, which is highlighted in the literature, with slower response times when the participants identified the laterality of hand images that corresponded to the immobilized hand. Importantly, the grip-precision effect, highlighted by slower response times for hands grasping a small sphere versus a large sphere, is impaired by 24 hours of limb nonuse. Overall, this study provided additional evidence of the disengagement of sensorimotor processes due to a short period of limb immobilization.

scholarly journals An Input–Output Ex Ante Regional Model to Assess the Short-Term Net Effects of the 16 April 2016 Earthquake in Ecuador

2021 ◽  
Author(s):  
Jorge Salgado ◽  
José Ramírez-Álvarez ◽  
Diego Mancheno
Keyword(s):  
Natural Hazard ◽  
National Accounts ◽  
Input Output ◽  
Short Term ◽  
Ex Ante ◽  
The Impact ◽  
Consumption Demand ◽  
Two Sectors ◽  
Positive Effect

AbstractThe 16 April 2016 earthquake in Ecuador exposed the significant weaknesses concerning the methodological designs to compute—from an economic standpoint—the consequences of a natural hazard-related disaster for productive exchanges and the accumulation of capital in Ecuador. This study addressed one of these challenges with an innovative ex ante model to measure the partial and net short-term effects of a natural hazard-related catastrophe from an interregional perspective, with the 16 April 2016 earthquake serving as a case study. In general, the specified and estimated model follows the approach of the extended Miyazawa model, which endogenizes consumption demand in a standard input–output model with the subnational interrelations and resulting multipliers. Due to the country’s limitations in its regional account records the input–output matrices for each province of Ecuador had to be estimated, which then allowed transactions carried out between any two sectors within or outside a given province to be identified by means of the RAS method. The estimations provide evidence that the net short-term impact on the national accounts was not significant, and under some of the simulated scenarios, based on the official information with respect to earthquake management, the impact may even have had a positive effect on the growth of the national product during 2016.

scholarly journals Clinical and microbiological evaluation of one-stage full-mouth disinfection: a short-term study

2013 ◽  
Vol 42 (4) ◽  
pp. 298-303
Author(s):  
José Roberto Cortelli ◽  
Marcos Vinicius Moreira de Castro ◽  
Rodrigo Dalla Pria Balejo ◽  
Camila Oliveira de Alencar ◽  
Antonio Carlos Gargioni Filho ◽  
...  
Keyword(s):  
Chronic Periodontitis ◽  
Bacterial Load ◽  
Periodontal Treatment ◽  
Periodontal Pocket ◽  
Short Term ◽  
Term Study ◽  
One Stage ◽  
Short Term Study ◽  
Short Period ◽  
Full Mouth Disinfection

INTRODUCTION: Patients seem to adhere better to short-term periodontal treatment schemes. Besides, time-reduced treatments are more cost-effective. However, the degree of benefits related to this type of treatment still requires additional investigations. AIM: The present short-term study evaluated clinical and microbiological outcomes, from baseline to 3-months, of chronic periodontitis subjects treated by the one-stage full-mouth disinfection protocol. MATERIAL AND METHOD: Sixteen chronic periodontitis subjects (mean-age 49.87 ± 8.22) who met inclusion/exclusion criteria were included. A calibrated examiner measured whole-mouth plaque and gingival indices, periodontal pocket depth and clinical attachment level at baseline and at 3-months. Subgingival samples were also collected from the 5 most diseased periodontal sites to determine total bacterial load and levels of P. gingivalis and S. oralis by real time qPCR. Periodontal treatment consisted of full-mouth manual debridement plus wide intraoral use of chlorhexidine in gel and solution. Additionally, after debridement, individuals rinsed 0.12% chlorhexidine at home twice a day for the following 2 months. Data monitored were compared by paired Student-t test (p<0.05). RESULT: Statistical analysis revealed that, in general, one-stage full-mouth disinfection treatment provided significant clinical and microbiological improvements at 3-months. Total bacterial load showed one of the most pronounced reductions from baseline to 3-months (p=0.0001). Also, subgingival levels P. gingivalis and S. oralis reduced overtime. CONCLUSION: After a short period of monitoring, chronic periodontitis subjects showed clinical and microbial improvements following one-stage full-mouth disinfection treatment.

scholarly journals Using O<sub>2</sub> to study the relationships between soil CO<sub>2</sub> efflux and soil respiration

2015 ◽  
Vol 12 (7) ◽  
pp. 2089-2099 ◽  
Author(s):  
A. Angert ◽  
D. Yakir ◽  
M. Rodeghiero ◽  
Y. Preisler ◽  
E. A. Davidson ◽  
...  
Keyword(s):  
Soil Respiration ◽  
Respiration Rate ◽  
Soil Profile ◽  
Soil Aggregates ◽  
Mineral Dissolution ◽  
Co2 Efflux ◽  
Short Term ◽  
Quantitative Evidence ◽  
High Soil Moisture ◽  
Bicarbonate Ions

Abstract. Soil respiration is the sum of respiration processes in the soil and is a major flux in the global carbon cycle. It is usually assumed that the CO2 efflux is equal to the soil respiration rate. Here we challenge this assumption by combining measurements of CO2 with high-precision measurements of O2. These measurements were conducted on different ecosystems and soil types and included measurements of air samples taken from the soil profile of three Mediterranean sites: a temperate forest and two alpine forests. Root-free soils from the alpine sites were also incubated in the lab. We found that the ratio between the CO2 efflux and the O2 influx (defined as apparent respiratory quotient, ARQ) was in the range of 0.14 to 1.23 and considerably deviated from the value of 0.9 ± 0.1 expected from the elemental composition of average plants and soil organic matter. At the Mediterranean sites, these deviations are explained as a result of CO2 dissolution in the soil water and transformation to bicarbonate ions in these high-pH soils, as well as by carbonate mineral dissolution and precipitation processes. Thus, a correct estimate of the short-term, chamber-based biological respiratory flux in such soils can only be made by dividing the measured soil CO2 efflux by the average (efflux-weighted) soil profile ARQ. Applying this approach to a semiarid pine forest resulted in an estimated short-term biological respiration rate that is 3.8 times higher than the chamber-measured surface CO2. The ARQ values often observed in the more acidic soils were unexpectedly low (< 0.7). These values probably result from the oxidation of reduced iron, which has been formed previously during times of high soil moisture and local anaerobic conditions inside soil aggregates. The results reported here provide direct quantitative evidence of a large temporal decoupling between soil–gas exchange fluxes and biological soil respiration.

scholarly journals Small time scale plankton structure variations at the entrance of a tropical eutrophic bay (Guanabara Bay, Brazil)

2012 ◽  
Vol 60 (4) ◽  
pp. 405-414 ◽  
Author(s):  
Mariana Guenther ◽  
Isabel Lima ◽  
Glenda Mugrabe ◽  
Denise Rivera Tenenbaum ◽  
Eliane Gonzalez-Rodriguez ◽  
...  
Keyword(s):  
Surface Layer ◽  
Photosynthetic Efficiency ◽  
Great Influence ◽  
Small Time ◽  
Guanabara Bay ◽  
Short Term ◽  
Mesozooplankton Biomass ◽  
Trophic Pathways ◽  
Se Brazil ◽  
Almost All

The dynamics of the plankton compartments at the entrance of Guanabara Bay (SE Brazil) were assessed during a short-term temporal survey to estimate their trophic correlations. Size-fractioned phytoplankton (picoplankton: < 2µm, nanoplankton: 2-20µm and microplankton: > 20µm) biomass and photosynthetic efficiency, composition and abundance of the auto-and heterotrophic nano-and microplankton, and mesozooplankton were evaluated at a fixed station for 3 consecutive days at 3-h intervals, in the surface and bottom (20m) layers. The variability of almost all plankton compartments in the surface layer was directly dependent on temperature, indicating the great influence of the circulation at the entrance of the bay on plankton structure. In the surface layer, the mesozooplankton seems to be sustained by both autotrophic nano-and picoplankton, this last being channeled through the microzooplankton. Near the bottom, both auto-and heterotrophic microplankton are probably supporting the mesozooplankton biomass. Our findings thus suggest that the entrance of Guanabara bay presents a multivorous food web, i.e., a combination of both grazing and microbial trophic pathways.

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