Production of conidia by Phomopsis convolvulus

1990 ◽  
Vol 36 (2) ◽  
pp. 86-91 ◽  
Author(s):  
Louise Morin ◽  
Alan K. Watson ◽  
Richard D. Reeleder
Keyword(s):  
Sucrose Solution ◽  
Negative Relationship ◽  
Solid Substrate ◽  
Water Soluble ◽  
Liquid Media ◽  
Production Methods ◽  
The Media ◽  
Nitrogen Ratio ◽  
Barley Grains ◽  
Complex Liquid

Various solid-substrate fermentation and shake-flask liquid fermentation systems were investigated as spore production methods for Phomopsis convolvulus, a potential bioherbicide. Among them, "pot" barley grains and modified Richard's (V-8) liquid medium produced 5 × 108 conidia/g and 5 × 106 conidia/mL, respectively. Distinct pycnidia, covering the surface of pot barley grains, produced virulent conidia in a water-soluble mucilage approximately 10 days after seeding the substrate with conidia. In complex liquid media, conidia were produced in pycnidia 3 to 4 days after seeding the media with mature pycnidia or conidia. A negative relationship was demonstrated between inoculum density and yield of conidia in modified Richard's (V-8) liquid culture. Omission of V-8 juice or decrease of the carbon to nitrogen ratio in modified Richard's (V-8) medium inhibited sporulation. Conidia lost viability after 30 days when held at −10 °C in a sucrose solution, but conidia stored at −70 °C remained viable and pathogenic for at least 6 months. Key words: Phomopsis convolvulus, bioherbicide, sporulation.

Polysaccharide production by kefir grains during whey fermentation

2001 ◽  
Vol 68 (4) ◽  
pp. 653-661 ◽  
Author(s):  
PABLO SEBASTIÁN RIMADA ◽  
ANALÍA GRACIELA ABRAHAM
Keyword(s):  
Soluble Fraction ◽  
Water Soluble ◽  
Grain Weight ◽  
Fermentation Time ◽  
Polysaccharide Fraction ◽  
Polysaccharide Production ◽  
Lactose Concentration ◽  
The Media ◽  
Soluble Polysaccharide ◽  
Kefir Grains

Fermentation of deproteinised whey with kefir grains CIDCA AGK1 was studied focusing on polysaccharide production from lactose. Kefir grains were able to acidify whey at different rates depending on the grain/whey ratio. During fermentation, kefir grains increased their weight and a water-soluble polysaccharide was released to the media. Exopolysaccharide concentration increased with fermentation time, reaching values of 57·2 and 103·4 mg/l after 5 days of fermentation in cultures with 10 and 100 g kefir grains/l, respectively. The polysaccharide fraction quantified after fermentation corresponded to the soluble fraction, because part of the polysaccharide became a component of the grain. Weight of kefir grains varied depending on the time of fermentation. Polysaccharide production was affected by temperature. Although the highest concentration of polysaccharide in the media was observed at 43 °C at both grain/whey ratios, the weight of the grains decreased in these conditions. In conclusion, kefir grains were able to acidify deproteinised whey, reducing lactose concentration, increasing their weight and producing a soluble polysaccharide.

Degradation of polycyclic aromatic hydrocarbons (PAHs) by a mixed culture and its component pure cultures, obtained from PAH-contaminated soil

1995 ◽  
Vol 41 (6) ◽  
pp. 470-476 ◽  
Author(s):  
D. Trzesicka-Mlynarz ◽  
O. P. Ward
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Mixed Culture ◽  
Aromatic Hydrocarbons ◽  
Aqueous Media ◽  
Water Soluble ◽  
Nitrogen Levels ◽  
Glucose Levels ◽  
Polycyclic Aromatic ◽  
Pure Cultures ◽  
The Media

A mixed culture, isolated from soil contaminated with polycyclic aromatic hydrocarbons (PAHs), grew on and degraded fluoranthene in aqueous media supplemented with glucose, yeast extract, and peptone. Increased complex nitrogen levels in the medium promoted bacterial growth and a greater extent of fluoranthene degradation. Amendment of the media with high glucose levels also diminished specific fluoranthene degradation. The mixed culture was capable of degrading a range of other PAHs, including benzo[a]pyrene, anthracene, phenanthrene, acenaphthene, and fluorene. The mixed culture contained four predominant isolates, all of which were Gram-negative rods, three of which were identified as Pseudomonas putida, Flavobacterium sp., and Pseudomonas aeruginosa. Better degradation of a defined PAH mixture was observed with the mixed culture than with individual isolates. A reconstituted culture, prepared by combining the four individual isolates, manifested a similar PAH biodegradation performance to the original mixed culture. When compared with the mixed culture, individual isolates exhibited a relatively good capacity to remove more water-soluble PAHs (acenaphthene, fluorene, phenanthrene, fluoranthene). In contrast, removal of less water-soluble PAHs (anthracene and pyrene) was low or negligible with isolated cultures compared with the mixed culture.Key words: polycyclic aromatic hydrocarbons, mixed culture, fluoranthene, Pseudomonas, Flavobacterium.

Is Snapchat Discover really a news platform? News snacking from social media and users’ knowledge of current affairs

2021 ◽  
Vol 00 (00) ◽  
pp. 1-23
Author(s):  
Jayeon Lee
Keyword(s):  
Social Media ◽  
Negative Relationship ◽  
The United States ◽  
Journalism Studies ◽  
Soft News ◽  
Current Affairs ◽  
Social Media Platforms ◽  
The Media ◽  
The Impact ◽  
Negative Predictor

The role of the media in informing the public has long been a central topic in journalism studies. Given that social media platforms have become today’s major source of news, it is important to understand the impact of social media use on citizens’ knowledge of current affairs. While people get news from multiple platforms throughout the day, most research treats social media as a single entity or examines only one or two major platforms ignoring newer social media platforms. Drawing on news snacking framework, this study investigates how using some of today’s most popular social media platforms predicts users’ current affairs knowledge, with particular attention to Snapchat and its news section Discover. A survey conducted in the United States (N=417) demonstrated that each of the platforms is distinct: Twitter is a strongly positive predictor of knowledge, Facebook a marginally significant negative predictor, Reddit a significantly negative predictor and Instagram not a significant predictor. Overall Snapchat use has no significant association with users’ knowledge of current affairs, whereas Discover use has a negative relationship. Further analysis revealed that mere exposure to Snapchat is positively related to soft-news knowledge and attention to Discover is negatively related to hard-news knowledge.

THE NATURE OF THE IMAGE WITHIN TECHNOLOGICAL ART IN THE MID – 20TH CENTURY. LUMINO KINETIC EXPERIMENTS BY FRANK MALINA

2021 ◽  
pp. 110-125
Author(s):  
Irina N. Zakharchenko ◽  
◽  
Olga M. Shchedrina ◽  
Keyword(s):  
Visual Culture ◽  
Academic Science ◽  
Academic Environment ◽  
Production Methods ◽  
Kinetic Art ◽  
Artistic Medium ◽  
The Media ◽  
Working Practices ◽  
Processing Algorithms ◽  
First Time

For the first time in the Russian-speaking academic environment the authors of the paper analyze the creative legacy of the scientist, aeronautical engineer and artist Frank Joseph Malina (1912–1981). His working practices reflected the most important ethic and aesthetic aspirations of the mid-twentieth century, what became an important contribution to the development of modern visual culture. The pioneer of Lumino Kinetic art F.Malina created several unique electromechanical systems for the production of an image, the media infrastructure and technological nature of which would later become the visual standard of the digital age. The discovery of electric light as a new artistic medium allowed him to focus on the production methods, control and processing algorithms for light that produces images. The Lumino Kinetic experiments of F. Malina are based on understanding the new nature of the image, born during the era of scientific discoveries. Several decades before the iconic turn was proclaimed by academic science, they presented the image as a system of relations that is formed in acts of perception and that is not based on visible, but felt, ideated, imagined reality. While creating his works F. Malina dreamed of modeling qualitatively new perceptual conditions for the existence of mankind aimed at further progress and traveling to the stars.

scholarly journals Longevity extension of worker honey bees (Apis mellifera) by royal jelly: optimal dose and active ingredient

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3118 ◽  
Author(s):  
Wenchao Yang ◽  
Yuanyuan Tian ◽  
Mingfeng Han ◽  
Xiaoqing Miao
Keyword(s):  
Apis Mellifera ◽  
Ammonium Sulfate ◽  
Honey Bees ◽  
Royal Jelly ◽  
Sucrose Solution ◽  
Ethanol Extract ◽  
Optimal Dose ◽  
Water Soluble ◽  
Main Component ◽  
Colony Productivity

In the Western honey bee, Apis mellifera, queens and workers have different longevity although they share the same genome. Queens consume royal jelly (RJ) as the main food throughout their life, including as adults, but workers only eat worker jelly when they are larvae less than 3 days old. In order to explore the effect of RJ and the components affecting longevity of worker honey bees, we first determined the optimal dose for prolonging longevity of workers as 4% RJ in 50% sucrose solution, and developed a method of obtaining long lived workers. We then compared the effects of longevity extension by RJ 4% with bee-collected pollen from rapeseed (Brassica napus). Lastly, we determined that a water soluble RJ protein obtained by precipitation with 60% ammonium sulfate (RJP60) contained the main component for longevity extension after comparing the effects of RJ crude protein extract (RJCP), RJP30 (obtained by precipitation with 30% ammonium sulfate), and RJ ethanol extract (RJEE). Understanding what regulates worker longevity has potential to help increase colony productivity and improve crop pollination efficiency.

Determination of ethanol in complex liquid media for continuous processing control

1989 ◽  
Vol 37 (3) ◽  
pp. 680-684 ◽  
Author(s):  
Elisabeth D. Dumoulin ◽  
Stephane L. Mazette ◽  
Pierre O. Cogat ◽  
Jacqueline T. Guerain
Keyword(s):  
Continuous Processing ◽  
Liquid Media ◽  
Processing Control ◽  
Complex Liquid

The Influence of Liquid Media on the Fracture Strength of Polysilicon Nanostructures

2012 ◽  
Vol 187 ◽  
pp. 127-130
Author(s):  
Daniel Peter ◽  
Michael Dalmer ◽  
Alfred Lechner ◽  
Alexander M. Gigler ◽  
Robert W. Stark ◽  
...  
Keyword(s):  
Fracture Strength ◽  
Mechanical Stability ◽  
Surrounding Medium ◽  
Lateral Force ◽  
Liquid Media ◽  
Self Assembled Monolayer ◽  
Fracture Force ◽  
Force Microscopy ◽  
The Media ◽  
Reported Data

The mechanical stability of nanostructures depends on the surrounding medium. Their stability was probed by lateral force microscopy in liquid media. Previously reported data on water and isopropanol showed an increase in the fracture strength for the latter. Further tests with other alcohols (ethanol, 1-butanol) also showed an increasing strength. The interface between the liquid and the surface is the decisive factor for the influence of the media. When altering the interface with a cationic surfactant or a self-assembled monolayer, an increase of the fracture force by 100 % compared to de-ionized water could be measured.

Urease activity related to the growth and differentiation of swarmer cells of Proteus mirabilis

1987 ◽  
Vol 33 (4) ◽  
pp. 300-303 ◽  
Author(s):  
Tianru Jin ◽  
R. G. E. Murray
Keyword(s):  
Proteus Mirabilis ◽  
Urease Activity ◽  
Casein Hydrolysate ◽  
Brain Heart Infusion ◽  
Liquid Media ◽  
Whole Cells ◽  
Maximum Proportion ◽  
The Media ◽  
Urease Production ◽  
Different Strains

Urease activity was measured using whole cells of both long (swarming) and short (nonswarming) populations of Proteus mirabilis from casein hydrolysate agar (CHA) and broth (CHB) cultures, and from brain heart infusion broth (BHIB) cultures. Urease is a constitutive enzyme for both long and short cells, but its activity was tremendously increased when urea was incorporated into the media. Urease production was also affected by culture age and media used. Before exponential phase, urease activity was very low, and it increased to its highest point after about 4 h in BHIB and 8 h in both CHA and CHB cultures at 37 °C. Long cells had higher urease activity than did short cells when grown on CHA, and was also expressed by two different strains cultured in BHIB. Strain PM23, in BHIB, was able to form long cells (swarming cells) to a maximum proportion after about 4 h, but strain IM47 could not differentiate in any of the liquid media. The former had more urease when swarming differentiation was initiated. PM23 grew relatively faster than IM47 when the former began to differentiate, but this fast growth could not be observed when nutrient broth or minimal medium was used. These observations suggest that long or swarming cells are "faster growing" rather than "nongrowing bactera."

scholarly journals Growth of Poinsettias, Nutrient Leaching, and Water-use Efficiency Respond to Irrigation Methods

HortScience ◽  
1994 ◽  
Vol 29 (8) ◽  
pp. 858-864 ◽  
Author(s):  
John M. Dole ◽  
Janet C. Cole ◽  
Sharon L. von Broembsen
Keyword(s):  
Nitrogen Concentration ◽  
Dry Weight ◽  
Water Soluble ◽  
Euphorbia Pulcherrima ◽  
The Media ◽  
Use Efficiency ◽  
Total Dry Weight ◽  
Soluble Fertilizer ◽  
Mn Concentration ◽  
Ebb And Flow

`Gutbier V-14 Glory' poinsettias (Euphorbia pulcherrima Willd. Ex. Klotzsch) grown with ebb-and-flow irrigation used the least amount of water and produced the least runoff, and plants grown with capillary mats used the greatest amount of water and produced the most runoff, compared to microtube and hand-watering systems. The maximum amount of water retained by the pots and media was greatest for the microtube and ebb-and-flow systems and became progressively lower for the hand-watering and capillary mat systems. The media and leachate electrical conductivity from plants grown with subirrigation systems was higher than those grown with top irrigation. For the two top-irrigation systems (microtube and hand-watering), plants grown with 250 mg N/liter from a 20N-4.4P-16.6K water-soluble fertilizer had greater leaf, stem, and total dry weights than those grown with 175 mg N/liter. The two subirrigation systems (ebb-and-flow and capillary mat) produced plants that were taller and had greater leaf, stem, and total dry weights when grown with 175 than with 250 mg N/liter. The higher fertilizer concentration led to increased N, P, Fe, and Mn concentration in the foliage. Nitrogen concentration was higher in top-irrigated plants than in subirrigated plants. The ebb-and-flow system produced the greatest total dry weight per liter of water applied and per liter of runoff; capillary mat watering was the least efficient in regard to water applied and runoff.

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