scholarly journals Molecular and Immunological Methods to Confirm Toxiginicity (Microcystin Production) of Westiellopsis Prolifica Isolated from Tigris River – Iraq

2019 ◽  
Vol 16 (4(Suppl.)) ◽  
pp. 0978
Author(s):  
Abed Et al.
Keyword(s):  
Laboratory Experiments ◽  
Immunological Methods ◽  
Laboratory Methods ◽  
Tigris River ◽  
Cyanobacterial Species ◽  
The World ◽  
Mcye Gene ◽  
Microcystin Production ◽  
Westiellopsis Prolifica ◽  
Significant Expression

Several toxigenic cyanobacteria produce the cyanotoxin (microcystin). Being a health and environmental hazard, screening of water sources for the presence of microcystin is increasingly becoming a recommended environmental procedure in many countries of the world. This study was conducted to assess the ability of freshwater cyanobacterial species Westiellopsis prolifica to produce microcystins in Iraqi freshwaters via using molecular and immunological tools. The toxigenicity of W. prolifica was compared via laboratory experiments with other dominant bloom-forming cyanobacteria isolated from the Tigris River: Microcystis aeruginosa, Chroococcus turigidus, Nostoc carneum, and Lyngbya sp. significant expression of mcyE gene and microcystin production was most evident in W. prolifica. Contrary to the prevailing concept that M. aeruginosa is a main microcystin producer in freshwaters around the world, no significant microcystin production was observed with this species throughout the time points studied in our laboratory methods. As for C. turigidus, N. carneum and Lyngbya sp., neither mcyE expression nor microcystin production was significant. Data from mcyE expression by RT-qPCR were generally in agreement with those obtained from microcystin quantification by ELISA. Interestingly, W. prolifica, which showed clear microcystin-producing ability in this study and which was not reported before in the literature to produce microcystin, can be added as a new microcystin producer to the list of toxigenic cyanobacteria.

scholarly journals Molecular Detection of Some Toxigenic Cyanobacteria in Tigris River in Baghdad–Iraq

2021 ◽  
Author(s):  
Noor Redha Gummaa ◽  
Ahmed Sahi Dwaish ◽  
Israa Hussein Hamzah
Keyword(s):  
Drinking Water ◽  
Molecular Detection ◽  
Gene Fragment ◽  
Nostoc Commune ◽  
Pcr Assay ◽  
The Public ◽  
Tigris River ◽  
The World ◽  
Westiellopsis Prolifica ◽  
Algal Toxin

Abstract Cyanobacteria and their emissions are becoming more widely reported around the world, posing a serious threat to both the environment and human health. Several orders of cyanobacteria have been identified to make cyanotoxin, the most common algal toxin. The aim of this research was to develop a method for detecting cylindrosprmopsin and saxitoxin biosynthesis genes in rivers .In November, December 2019 and January2020. Cyanobacteria were isolated from Tigris River freshwater and detected using a compound microscope as well as traditional PCR .All cyanobacteria isolates contained phycocyanin gene fragment. Five isolates of cyanobacteria in these study was successfully amplified a phycocyanin gene (Microcystis flosaquae, Microcystis sp, anabaena circinalis ,nostoc commune and westiellopsis prolifica) and all isolates successfully amplified aoaC gene to detecting the cylidrospemopsin and the saxitoxin. Our findings show that a PCR assay can be used to detect cylidrospemopsin and saxitoxin-producing cyanobacteria in river water, which is useful for stations that prepare drinking water for the public.

scholarly journals Diversity of cyanobacteria and cyanotoxins in Hartbeespoort Dam, South Africa

2014 ◽  
Vol 65 (2) ◽  
pp. 175 ◽  
Author(s):  
Andreas Ballot ◽  
Morten Sandvik ◽  
Thomas Rundberget ◽  
Christo J. Botha ◽  
Christopher O. Miles
Keyword(s):  
South African ◽  
Toxin Production ◽  
Cyanobacterial Species ◽  
Microcystis Blooms ◽  
Liquid Chromatography Tandem Mass ◽  
Mcye Gene ◽  
Microcystis Strain ◽  
Microcystin Production ◽  
Encoding Gene ◽  
Encoding Genes

The South African Hartbeespoort Dam is known for the occurrence of heavy Microcystis blooms. Although a few other cyanobacterial genera have been described, no detailed study on those cyanobacteria and their potential toxin production has been conducted. The diversity of cyanobacterial species and toxins is most probably underestimated. To ascertain the cyanobacterial composition and presence of cyanobacterial toxins in Hartbeespoort Dam, water samples were collected in April 2011. In a polyphasic approach, 27 isolated cyanobacterial strains were classified morphologically and phylogenetically and tested for microcystins (MCs), cylindrospermopsin (CYN), saxitoxins (STXs) and anatoxin-a (ATX) by liquid chromatography–tandem mass spectrometry (LC–MS/MS) and screened for toxin-encoding gene fragments. The isolated strains were identified as Sphaerospermopsis reniformis, Sphaerospermopsis aphanizomenoides, Cylindrospermopsis curvispora, Raphidiopsis curvata, Raphidiopsis mediterrranea and Microcystis aeruginosa. Only one of the Microcystis strains (AB2011/53) produced microcystins (35 variants). Forty-one microcystin variants were detected in the environmental sample from Hartbeespoort Dam, suggesting the existence of other microcystin producing strains in Hartbeespoort Dam. All investigated strains tested negative for CYN, STXs and ATX and their encoding genes. The mcyE gene of the microcystin gene cluster was found in the microcystin-producing Microcystis strain AB2011/53 and in eight non-microcystin-producing Microcystis strains, indicating that mcyE is not a good surrogate for microcystin production in environmental samples.

Ups and Downs

2018 ◽  
Author(s):  
Roy Livermore
Keyword(s):  
Mantle Convection ◽  
Laboratory Experiments ◽  
Inner Core ◽  
Computer Modelling ◽  
Great Depth ◽  
New Horizons ◽  
The Core ◽  
The Earth ◽  
The World ◽  
The 1960S

Despite the dumbing-down of education in recent years, it would be unusual to find a ten-year-old who could not name the major continents on a map of the world. Yet how many adults have the faintest idea of the structures that exist within the Earth? Understandably, knowledge is limited by the fact that the Earth’s interior is less accessible than the surface of Pluto, mapped in 2016 by the NASA New Horizons spacecraft. Indeed, Pluto, 7.5 billion kilometres from Earth, was discovered six years earlier than the similar-sized inner core of our planet. Fortunately, modern seismic techniques enable us to image the mantle right down to the core, while laboratory experiments simulating the pressures and temperatures at great depth, combined with computer modelling of mantle convection, help identify its mineral and chemical composition. The results are providing the most rapid advances in our understanding of how this planet works since the great revolution of the 1960s.

From Silent Spring to The Frog of War

2017 ◽  
Author(s):  
David K. Skelly
Keyword(s):  
Natural History ◽  
Laboratory Experiments ◽  
Wild Populations ◽  
Rachel Carson ◽  
Chemical Agents ◽  
Silent Spring ◽  
The World ◽  
History Information ◽  
Wildlife Populations ◽  
The Impact

This chapter presents two examples to demonstrate that natural history is the necessary basis of any reliable understanding of the world. More than a half century ago, Rachel Carson revolutionized the public’s view of pesticides. The foundation of her success was the careful use of natural history data, collated from across North America. The examples she assembled left little doubt that DDT and other pesticides were causing a widespread decline in birds. More recently, the case for the impact of atrazine on wildlife was based on laboratory experiments, without the advantage of natural history observations. For atrazine, natural history observations now suggest that other chemical agents are more likely to be responsible for feminization of wildlife populations. Developing expectations for scientists to collect natural history information can help to avoid over-extrapolating lab results to wild populations, a tendency often seen when those lab results conform to preconceptions about chemicals in the environment.

The “is-ought fallacy” fallacy

2011 ◽  
Vol 34 (5) ◽  
pp. 262-263 ◽  
Author(s):  
Mike Oaksford ◽  
Nick Chater
Keyword(s):  
Laboratory Experiments ◽  
Rational Analysis ◽  
The World

AbstractMere facts about how the world is cannot determine how we ought to think or behave. Elqayam & Evans (E&E) argue that this “is-ought fallacy” undercuts the use of rational analysis in explaining how people reason, by ourselves and with others. But this presumed application of the “is-ought” fallacy is itself fallacious. Rational analysis seeks to explain how people do reason, for example in laboratory experiments, not how they ought to reason. Thus, no ought is derived from an is; and rational analysis is unchallenged by E&E's arguments.

scholarly journals A global quantification of “normal” sleep schedules using smartphone data

2016 ◽  
Vol 2 (5) ◽  
pp. e1501705 ◽  
Author(s):  
Olivia J. Walch ◽  
Amy Cochran ◽  
Daniel B. Forger
Keyword(s):  
Laboratory Experiments ◽  
Population Level ◽  
Light Level ◽  
Sleep Scheduling ◽  
Sleep Habits ◽  
Wake Time ◽  
Sleep Timing ◽  
The World ◽  
Primary Determinant ◽  
Normal Sleep

The influence of the circadian clock on sleep scheduling has been studied extensively in the laboratory; however, the effects of society on sleep remain largely unquantified. We show how a smartphone app that we have developed, ENTRAIN, accurately collects data on sleep habits around the world. Through mathematical modeling and statistics, we find that social pressures weaken and/or conceal biological drives in the evening, leading individuals to delay their bedtime and shorten their sleep. A country’s average bedtime, but not average wake time, predicts sleep duration. We further show that mathematical models based on controlled laboratory experiments predict qualitative trends in sunrise, sunset, and light level; however, these effects are attenuated in the real world around bedtime. Additionally, we find that women schedule more sleep than men and that users reporting that they are typically exposed to outdoor light go to sleep earlier and sleep more than those reporting indoor light. Finally, we find that age is the primary determinant of sleep timing, and that age plays an important role in the variability of population-level sleep habits. This work better defines and personalizes “normal” sleep, produces hypotheses for future testing in the laboratory, and suggests important ways to counteract the global sleep crisis.

scholarly journals Potential Effect of Pomegranate Peels Extract (Punica Granatum.) against Covid-19 Virus .

2021 ◽  
Author(s):  
Ashraf fawzy mosa ◽  
Mostafa abo Elhoda Mohamed
Keyword(s):  
Tissue Culture ◽  
Water Extract ◽  
Punica Granatum ◽  
Inhibitory Effect ◽  
Potential Effect ◽  
Laboratory Methods ◽  
Global Epidemic ◽  
Ic50 Value ◽  
The World

Abstract Background: Covid-19 Virus infection poses significant global health challenges and considered a global epidemic sweeping all countries of the world Which prompted scientists around the world to search for a quick or safe treatment to preserve people's lives .So far, options for controlling and treating the disease have not been revealed. The current study was conducted to evaluate the effectiveness of pomegranate peels extract against the Covid-19 virus in the laboratory. Methods: In this research, tow methods of extraction are carried out ethyl alcohol and distal water extract of pomegranate peels . activity of the extract assessed using 50% Tissue Culture Infectious Doses (TCID50) method in Vero E6 cells. Results: Pomegranate peels extract had the highest inhibitory effect against Covid -19 virus with IC50 value of 0.125, 0.0625 and 0.031256 μl in Vero E6 cells. Conclusion: Based on our results, the aqueous extract of pomegranate peels can inhibit Covid-19 virus replication in vitro.

scholarly journals Fluoride Variations in Rivers on the Slopes of Mount Meru in Tanzania

2018 ◽  
Vol 2018 ◽  
pp. 1-18 ◽  
Author(s):  
Aldo J. Kitalika ◽  
Revocatus L. Machunda ◽  
Hans C. Komakech ◽  
Karoli N. Njau
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Laboratory Experiments ◽  
Fluoride Concentration ◽  
Ion Selective Electrode ◽  
World Health ◽  
Wet Season ◽  
Selective Electrode ◽  
Fluoride Ions ◽  
The World

This study reports the variations of fluoride ions in rivers on the slopes of Mount Meru in the northern part of Tanzania. More than 318 water samples were collected from Temi, Nduruma, Tengeru, and Maji ya Chai Rivers in both wet (mid-March and April) and dry (August) seasons. The samples were analyzed for fluoride levels using Ion Selective Electrode (ISE). The minimum and maximum average fluoride levels in the wet season were 0.24±0.03 mg/l and 65.20±0.03 mg/l, respectively, whereas the average lowest and highest levels in the dry season were 1.02±0.02 mg/l and 69.01±0.03 mg/l, respectively. Tengeru River had the lowest fluoride levels in both seasons, whereas Maji ya Chai recorded the highest fluoride levels in both seasons. The headwater of all rivers with the exception of Maji ya Chai met the World Health Organization’s (WHO) maximum acceptable fluoride levels of 1.50 mg/l and the downstream environment qualified for Tanzania Bureau of Standards (TBS) maximum permissible fluoride concentration in drinking water of 4.00 mg/l. Also, the laboratory experiments showed that fluoride containing rocks exposed to pH above 7.6 display high leaching of F− in solution which gradually increased with the increase in pH, indicating that dissolution of fluoride in water is a function of pH.

scholarly journals An introduction to the mechanics of the lasso

2014 ◽  
Vol 470 (2171) ◽  
pp. 20140512 ◽  
Author(s):  
Pierre-Thomas Brun ◽  
Neil Ribe ◽  
Basile Audoly
Keyword(s):  
Boundary Layer ◽  
Horizontal Plane ◽  
Laboratory Experiments ◽  
String Model ◽  
Line Tension ◽  
Static Friction ◽  
The Other ◽  
Numerical Continuation ◽  
The World ◽  
Small Loop

Trick roping evolved from humble origins as a cattle-catching tool into a sport that delights audiences all over the world with its complex patterns or ‘tricks’. Its fundamental tool is the lasso, formed by passing one end of a rope through a small loop (the honda) at the other end. Here, we study the mechanics of the simplest rope trick, the Flat Loop , in which the rope is driven by the steady circular motion of the roper's hand in a horizontal plane. We first consider the case of a fixed (non-sliding) honda. Noting that the rope's shape is steady in the reference frame rotating with the hand, we analyse a string model in which line tension is balanced by the centrifugal force and the rope's weight. We use numerical continuation to classify the steadily rotating solutions in a bifurcation diagram and analyse their stability. In addition to Flat Loops , we find planar ‘coat-hanger’ solutions, and whirling modes in which the loop collapses onto itself. Next, we treat the more general case of a honda that can slide due to a finite coefficient of friction of the rope on itself. Using matched asymptotic expansions, we resolve the shape of the rope in the boundary layer near the honda where the rope's bending stiffness cannot be neglected. We use this solution to derive a macroscopic criterion for the sliding of the honda in terms of the microscopic Coulomb static friction criterion. Our predictions agree well with rapid-camera observations of a professional trick roper and with laboratory experiments using a ‘robo-cowboy’.

scholarly journals EXPERIMENTAL STUDY ON THE EFFECTS OF THE OFFSHORE NOURISHMENT USING THE COASER SANDS WITH THE CROSS-SHORE SEASONAL CHANGE

2012 ◽  
Vol 1 (33) ◽  
pp. 38
Author(s):  
Yoko Shibutani ◽  
Yuhei Matsubara ◽  
Masamitsu Kuroiwa ◽  
Noriko Yao
Keyword(s):  
Experimental Study ◽  
Seasonal Change ◽  
Laboratory Experiments ◽  
Sandy Beach ◽  
Beach Nourishment ◽  
The World ◽  
The Cross ◽  
Sand Nourishment ◽  
Study Laboratory

In recent decades, beach erosions have become severe at sandy beach in the world. The coarser sand nourishment has been noticed in Japan because of the stabilization of the beach coast. However the performance is not clear. Therefore in this study, laboratory experiments were conducted for the beach nourishment using the coarser sand. Through of this experiment, the effect of the coarser sand nourishment was investigated.

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