Is the Oort A-value a universal growth rate limit for accretion disk shear instabilities?

1992 ◽  
Vol 392 ◽  
pp. 662 ◽  
Author(s):  
Steven A. Balbus ◽  
John F. Hawley
Keyword(s):  
Growth Rate ◽  
Accretion Disk ◽  
A Value ◽  
Shear Instabilities ◽  
Rate Limit ◽  
Disk Shear

scholarly journals AKTIVITAS INULINASE OLEH Pichia manshurica DAN FUSAN F4 PADA FERMENTASI BATCH DENGAN UMBI DAHLIA (Dahlia sp) SEBAGAI SUBSTRAT

REAKTOR ◽  
2015 ◽  
Vol 14 (3) ◽  
pp. 187 ◽  
Author(s):  
Wijanarka Wijanarka ◽  
Endang Sutariningsih Soetarto ◽  
Kumala Dewi ◽  
Ari Indrianto
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Lag Phase ◽  
Growth Media ◽  
A Value ◽  
Inulinase Activity ◽  
Pichia Manshurica ◽  
Microbial Strains ◽  
Kinetics Of

ACTIVITY OF INULINASE OF Pichia Manshuria AND FUSAN F4 ON BATCH FERMENTATION UDING DAHLIA TUBER (Dahlia sp) AS A SUBSTRATE. A dahlia tuber is one of the common inulin rich crops. Inulin is formed by units of fructans, which are polymers of D-fructose. Inulinases (EC 3.2.1.7) catalyze the hydrolysis of inulin, producing fructooligosaccharides (FOS), inulooligosaccharides (IOS), pulullan, acetone, butanol and sorbitol, therefore dahlia tubers are used as growth media. The inulin hydrolyzing activity has been reported from various microbial strains Pichia manshurica and Fusan F4 which is the result of fusion protoplast. The objective of this study was to determine the activity of inulinase Pichia manshurica and Fusan F4 on the substrate dahlia tubers. Fusan F4 to increase inulinase activity compared with Pichia manshurica and to investigate the kinetics of specific growth rate (μ) and time double (g) from of Pichia manshurica and Fusan F4. The results showed that the exponential phase occurs at 0-12 hour without a lag phase. P. manshurica has a specific growth rate (μ) of 0.18/hour with time double (g) 3.90 hours and the inulinase enzyme activity of 0.56 IU, while for Fusan F4 consecutive has a value μ of 0.20/hour, g of 3.49 hours and the activity of 0.69 IU. The conclusion of this research is to improve Fusan F4 inulinase activity and the ability has to be better than the Pichia manshurica.Umbi dahlia merupakan salah satu umbi yang mengandung inulin. Inulin merupakan polimer fruktan yang dapat dipecah oleh enzim inulinase (E.C. 3.2.1.7) menjadi fruktosa. Fruktosa merupakan bahan baku dasar untuk pembuatan FOS, IOS, pulullan, aseton dan sorbitol, oleh karena itu umbi dahlia digunakan sebagai media pertumbuhan. Enzim inulinase ini secara indigenous dimiliki oleh Pichia manshurica dan Fusan F4 yang merupakan hasil fusi protoplas.Tujuan  penelitian ini adalah  untuk mengetahui aktivitas inulinase Pichia manshurica dan Fusan F4 pada substrat umbi dahlia, Fusan F4 mampu meningkatkan aktivitas inulinase dibandingkan dengan Pichia manshurica serta untuk mengetahui kinetika kecepatan pertumbuhan specifik (µ) dan waktu generasi (g) Pichia manshurica dan Fusan F4. Hasil penelitian menunjukkan bahwa fase  eksponensial terjadi pada jam ke-0 sampai jam ke-12 tanpa diikuti fase lag, Pichia manshurica mempunyai kecepatan pertumbuhan specific (µ)  sebesar 0,18/jam dengan waktu generasi (g) 3,90 jam dan aktivitas enzim inulinase yang dihasilkan sebesar 0,56 IU, sedangkan untuk fusan F4 secara berturut-turut mempunyai nilai µ sebesar 0,20/jam, g sebesar 3,49 jam dan aktivitas sebesar 0,69 IU. Kesimpulan dari penelitian ini adalah Fusan F4 mampu meningkatkan aktivitas inulinase dan mempunyai kemampuan lebih baik dibanding dengan Pichia manshurica.

scholarly journals Covid-19 Outbreak Progression in Italian Regions: Approaching the Peak by the End of March in Northern Italy and First Week of April in Southern Italy

2020 ◽  
Vol 17 (9) ◽  
pp. 3025 ◽  
Author(s):  
Cosimo Distante ◽  
Prisco Piscitelli ◽  
Alessandro Miani
Keyword(s):  
Growth Rate ◽  
National Level ◽  
Compartment Model ◽  
Campania Region ◽  
Chinese City ◽  
A Value ◽  
Italian Regions ◽  
Northern Regions ◽  
Heavy Burden ◽  
Day By Day

Epidemiological figures of the SARS-CoV-2 epidemic in Italy are higher than those observed in China. Our objective was to model the SARS-CoV-2 outbreak progression in Italian regions vs. Lombardy to assess the epidemic’s progression. Our setting was Italy, and especially Lombardy, which is experiencing a heavy burden of SARS-CoV-2 infections. The peak of new daily cases of the epidemic has been reached on the 29th, while was delayed in Central and Southern Italian regions compared to Northern ones. In our models, we estimated the basic reproduction number (R0), which represents the average number of people that can be infected by a person who has already acquired the infection, both by fitting the exponential growth rate of the infection across a 1-month period and also by using day-by-day assessments based on single observations. We used the susceptible–exposed–infected–removed (SEIR) compartment model to predict the spreading of the pandemic in Italy. The two methods provide an agreement of values, although the first method based on exponential fit should provide a better estimation, being computed on the entire time series. Taking into account the growth rate of the infection across a 1-month period, each infected person in Lombardy has involved 4 other people (3.6 based on data of April 23rd) compared to a value of R 0 = 2.68 , as reported in the Chinese city of Wuhan. According to our model, Piedmont, Veneto, Emilia Romagna, Tuscany and Marche will reach an R0 value of up to 3.5. The R0 was 3.11 for Lazio and 3.14 for the Campania region, where the latter showed the highest value among the Southern Italian regions, followed by Apulia (3.11), Sicily (2.99), Abruzzo (3.0), Calabria (2.84), Basilicata (2.66), and Molise (2.6). The R0 value is decreased in Lombardy and the Northern regions, while it is increased in Central and Southern regions. The expected peak of the SEIR model is set at the end of March, at a national level, with Southern Italian regions reaching the peak in the first days of April. Regarding the strengths and limitations of this study, our model is based on assumptions that might not exactly correspond to the evolution of the epidemic. What we know about the SARS-CoV-2 epidemic is based on Chinese data that seems to be different than those from Italy; Lombardy is experiencing an evolution of the epidemic that seems unique inside Italy and Europe, probably due to demographic and environmental factors.

MHD Turbulence in an Accretion Disk

1995 ◽  
Vol 12 (2) ◽  
pp. 159-164 ◽  
Author(s):  
John F. Hawley ◽  
Steven A. Balbus
Keyword(s):  
Magnetic Field ◽  
Angular Momentum ◽  
Shear Flow ◽  
Accretion Disk ◽  
Accretion Disks ◽  
Reynolds Stresses ◽  
Mhd Turbulence ◽  
Mhd Instability ◽  
Standing Problem ◽  
Disk Shear

AbstractA long-standing problem in the theory of astrophysical accretion disks has been to determine the nature of the stress that transports orbital angular momentum outward. The discovery of a local MHD instability is strong evidence that transport occurs through turbulent Maxwell and Reynolds stresses. Using numerical simulations, we have demonstrated that a weak seed magnetic field in an accretion disk shear flow is unstable and leads to sustained MHD turbulence at dynamically important levels.

scholarly journals EFEKTIVITAS KOMPOSISI PROBIOTIK YANG BERBEDA PADA TEKNOLOGI AKUAPONIK UNTUK MENGOPTIMALKAN LAJU PERTUMBUHAN DAN KONVERSI PAKAN IKAN GABUS (Channa sp.)

2020 ◽  
Vol 7 (1) ◽  
pp. 85
Author(s):  
Fazril Saputra ◽  
Muhammad Agam Thahir ◽  
Mahendra Mahendra ◽  
Yusran Ibrahim ◽  
Muhammad Arif Nasution ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Growth Rate ◽  
Lactobacillus Casei ◽  
Fish Farming ◽  
Conversion Ratio ◽  
Feed Conversion Ratio ◽  
Feed Conversion ◽  
Combination Treatments ◽  
A Value ◽  
Randomized Design

Snakehead (Channa sp.) was one of the superior freshwater fish species native to Indonesia that has been successfully domesticated. The increasing demand for snakehead fish on the market has resulted in the addition of cultivated land and water use. Aquaponics technology was a combination of fish farming and plants that grow without soil media. The aim of this research was to determine the best composition of probiotics that can be used in aquaponic technology to optimize growth rate and feed conversion of snakehead fish (Channa sp.). This research used an experimental method. The experimental design used was a completely randomized design with four probiotic combination treatments and each treatment was repeated three times. The results showed that awarding of different probiotic compositions in the aquaponic system resulted in a spesific growth rate that was not significantly (P>0.05) different between treatments. The highest value of spesific growth rate were in the treatment of probiotic composition of Lactobacillus casei and Saccharomyces cerevisiae with a value of 4.11%/ day. Awarding of different probiotic compositions in the aquaponic system results in significantly (P<0.05) different feed conversion ratio values. The best feed conversion ratio values were in the treatment of probiotic composition of Lactobacillus casei and Saccharomyces cerevisiae with a value of 1.78. The conclusion of this study was the composition of probiotic Lactobacillus casei and Saccharomyces cerevisiae was the best probiotic composition to increase the spesific growth rate and feed conversion ratio of snakehead fish.

scholarly journals Covid-19 Outbreak Progression in Italian Regions: Approaching the Peak by March 29th

2020 ◽  
Author(s):  
Cosimo Distante ◽  
Prisco Piscitelli ◽  
Alessandro Miani
Keyword(s):  
Growth Rate ◽  
National Level ◽  
Compartment Model ◽  
Campania Region ◽  
Lombardy Region ◽  
A Value ◽  
Italian Regions ◽  
Northern Regions ◽  
Heavy Burden ◽  
Day By Day

AbstractBackgroundItaly and especially the Lombardy region is experiencing a heavy burden of Covid-19 infection. The peak of the epidemics has not yet been reached and it is expected to be delayed in Central and Southern Italian regions compared to Northern ones. We have modeled the Covid-19 outbreak progression in Italian Regions vs. Lombardy.MethodsIn our models, we have estimated the basic reproduction number (R0) -which represents the average number of people that can be infected by a person who has already acquired the infection - both by fitting the exponential growth rate of the infection across a 1-month period and also by using day by day assessment, based on single observations. We used the susceptible–exposed–infected–removed (SEIR) compartment model to predict the spreading of the pandemic in Italy.ResultsThe two methods provide agreements of values, although the first method based on exponential fit should provide a better estimation, being computed on the entire time series. Taking into account the growth rate of the infection across a 1-month period, in Lombardy each infected person has involved other 5 people (4.94 base on data of March 22nd vs. 5.07 based on data of March 19th) compared to a value of R0 = 2.68 reported in the Chinese city of Whuan. According to our model and Piedmont, Veneto, Emilia Romagna, Tuscany and Marche reach an R0 value up to 4. The R0 is 3.7 for Lazio and 3.6 for Campania region, where this latter shows the highest value among the Southern Italian regions, followed by Apulia (3.5), Sicily (3.4), Abruzzo (3.4), Calabria (3.1), Basilicata (2.5) and Molise (2.4). The value of R0 is decreasing in Lombardy and Northern Regions, while it is increasing in Central and Southern Regions.ConclusionThe expected peak of SEIR model can be forecast by the last week of March at national level, and by the first weeks of April in Southern Italian Regions. These kind of models can be useful for adoption of all the possible preventive measures, and to assess the epidemics progression across Southern regions as opposed to the Northern ones.

High Rate Growth of Highly-Crystallized Ge Films on Quartz from VHF Inductively-Coupled Plasma of GeH4 + H2

2007 ◽  
Vol 561-565 ◽  
pp. 1209-1212 ◽  
Author(s):  
Tsutomu Sakata ◽  
Katsunori Makihara ◽  
Hidenori Deki ◽  
Seiichiro Higashi ◽  
Seiichi Miyazaki
Keyword(s):  
Growth Rate ◽  
Inductively Coupled Plasma ◽  
Gas Flow ◽  
High Rate ◽  
Gas Flow Rate ◽  
Inductively Coupled ◽  
A Value ◽  
Disordered Phase ◽  
Integrated Intensity ◽  
Effective Growth

We have studied uniform growth of crystalline Ge films on quartz plate from VHF (60MHz)-ICP of 10% GeH4 diluted with H2 in the temperature range from 150 to 350°C. By optimizing total gas flow rate, gas pressure, VHF power and antenna-substrate distance, the growth rate as high as 7.4nm/s was obtained at 150°C and increased gradually up to ~7.9nm/s at 350°C. The crystallinity, which was evaluated by Raman scattering measurements as an integrated intensity ratio of TO phonons in crystalline phase to those in disordered phase, reached a value as high as ~93 % at 350°C, but degraded down to 64% at 150°C as a result of the formation of a 60~70nm-thick amorphous incubation (A. I.) layer on quartz. By applying a two-step deposition method at 150°C, in which the GeH4 concentration was selected to be 0.6% for the crystalline nucleation in the first 10s deposition, being as thin as 10nm in thickness, and then changed to 10% GeH4 for the high rate growth, the crystallinity was improved to 78% with keeping an effective growth rate as high as 7.5nm/s, because of a significant increase in the growth rate after the crystalline nucleation.

scholarly journals REKAYASA SALINITAS MEDIA PEMELIHARAAN SEBAGAI UPAYA DOMESTIKASI IKAN GIRU (Amphiprion ocellaris) YANG BERASAL DARI KEPULAUAN SIMEULUE

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Sufal Diansyah ◽  
Munandar Munandar ◽  
Afrijal Afrijal
Keyword(s):  
Growth Rate ◽  
Natural Habitat ◽  
Economic Value ◽  
Feed Conversion ◽  
A Value ◽  
Absolute Growth Rate ◽  
Value Range ◽  
Absolute Growth ◽  
The Absolute ◽  
Wild Life

Clownfish (Amphiprion ocellaris) is one reef fish that can be used as ornamental fish saltwater aquarium. The fish has high economic value because the color is attractive. However, this time facing the difficulty found the seeds found in nature as a result of uncontrolled harvesting, especially in the northwest district of Simeulue. The purpose of this study is a way of domestication of clownfish in a population that is almost extinct (endangered) of wild life (natural habitat) into the cultivation environment to determine the viability of a clownfish by administering salinity 32, 30, 28 and 26 ppt performed for 60 the aquariums in a container measuring 60 cm (long), 40 cm (wide) and 40 cm (high). The results showed that administration of different salinity did not significantly affect survival (p>0.05), while the absolute growth rate and feed conversion showed significant results (p<0.05), the value range of the absolute growth rate was ± 0.0014 to 0.00444 grams of feed conversion has a value range of ± 1,311- 5.190 grams.

scholarly journals Constraints on Growth Index from LSS

2014 ◽  
Vol 10 (S306) ◽  
pp. 255-257
Author(s):  
Athina Pouri ◽  
Spyros Basilakos ◽  
Manolis Plionis
Keyword(s):  
Growth Rate ◽  
Growth Index ◽  
Rate Data ◽  
Luminous Red Galaxies ◽  
A Value ◽  
Likelihood Analysis ◽  
Joint Likelihood ◽  
Λcdm Model ◽  
Red Galaxies ◽  
Good Agreement

AbstractWe utilize the clustering properties of the Luminous Red Galaxies (LRGs) and the growth rate data in order to constrain the growth index (γ) of the linear matter fluctuations based on a standard χ2joint likelihood analysis between theoretical expectations and data. We find a value of γ=0.56± 0.05, perfectly consistent with the expectations of the ΛCDM model, and Ωm0=0.29± 0.02, in very good agreement with the latest Planck results. Our analysis provides significantly more stringent growth index constraints with respect to previous studies as indicated by the fact that the corresponding uncertainty is only ∼ 0.09 γ.

Reliability Study on Crack Growth Rate of ADB610 Steel

2013 ◽  
Vol 690-693 ◽  
pp. 1741-1745
Author(s):  
Long Wei ◽  
Shi Yue Wang ◽  
Guo Shou Liu ◽  
Xi Jie Yang
Keyword(s):  
Growth Rate ◽  
Crack Growth Rate ◽  
Crack Growth ◽  
Growth Rates ◽  
Stress Ratio ◽  
Compact Tension ◽  
Compact Tension Specimen ◽  
Reliability Study ◽  
A Value ◽  
Crack Growth Rates

The test on fatigue crack growth rate of ADB610 steel is completed. The standard compact tension specimen is loaded by cyclic loading, whose stress ratio is constant at a value of R=0.1. Crack growth rates in the form of Paris formula at different survival levels are obtained by using three methods. After a simple comparison it is clear that crack growth rates obtained by three methods are generally same and the method based on (da/dN, delta K) has better effects on data analysis.

scholarly journals PENGARUH PEMBERIAN BIOCHAR TERHADAP BEBERAPA SIFAT BIOKIMIA TANAH DAN PERTUMBUHAN TANAMAN BAWANG MERAH PADA LAHAN TERCEMAR RESIDU PESTISIDA

2020 ◽  
Vol 8 (1) ◽  
pp. 27-34
Author(s):  
Sonni Senna Dimas Airlangga ◽  
Mochammad Munir ◽  
P Poniman
Keyword(s):  
Growth Rate ◽  
Block Design ◽  
Microbial Consortia ◽  
Microbial Populations ◽  
Organic C ◽  
Soil Microbial ◽  
A Value ◽  
Randomized Block Design ◽  
The Status ◽  
Number Of Leaves

The production of shallots in Brebes has not been significantly free from the use of chemical pesticides. Preventive land contaminated with pesticides needs to be done, one of which is through the improvement of polluted land using biochar. The study was aimed to determine the effectiveness of the effect of urea plus nano biochar and urea plus biochar enriched by microbial consortia on the status of C-organic, pH, and soil microbial populations and their effects on profenofos residues. The experiment was designed with a Randomized Block Design with 5 treatments including: P (without biochar and microbes), B (Urea plus biochar), BM (Urea plus biochar and microbial), NB (Urea plus nano biochar), NBM (Non-biochar and microbial) Urea added with nano biochar and microbes), and repeated 4 times, so that the number of research units was 20 units. The microbes used in enriching urea plus biochar are microbial consortia, Stenotrophomonas maltophilla, Achromobacter denitrificans, Bacillus cereus, Bacillus subtilis, Bacillus thuringiengsis and Bacillus aryabathai. The results of the study include, the administration of urea plus biochar and nano biochar with microbial consortia did not have a significant effect on pH, C-organics, soil microbial populations and profenofos residues. At 35 and 63 DAP the highest pH of treatment B was 5.84, and 6.53. Organic C-35 and 63 DAP at low criteria are 1.12 - 1.30%. The highest microbial population of 35 and 63 DAP in treatment B was 485 x 106. The highest growth rate of plant length in the BM treatment with a value of 6.06 cm week-1, while the growth rate of the number of leaves in the BM treatment had a higher yield compared to other treatments , with a value of 2.88 strands week-1.

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