Reconstruction of the volcanic history of the Tacámbaro-Puruarán area (Michoacán, México) reveals high frequency of Holocene monogenetic eruptions

Carboniferous Period.—The Lower Carboniferous rocks, both of the North of England, of Scotland, and of Ireland, afford examples of contemporaneous volcanic action of considerable intensity. The so-called “toad-stones” of Derbyshire, and the great sheets of melaphyre, porphyrite, and ashes of the central valley of Scotland, forming the Kilpatrick, Campsie, and Dairy Hills, appear to have been erupted over the bed of the same sea as that in which were poured out similar materials in County Limerick, forming the well-known Carboniferous volcanic rocks of “the Limerick Basin.” These rocks have been already so fully described by several observers, that I shall confine myself to a very short description, such as is essential to the brief history of volcanic action which I am here endeavouring to draw up.

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Gaining Insights in Loading Events for Wind Turbine Drivetrain Prognostics

Volume 12: Wind Energy ◽

10.1115/gt2020-15312 ◽

2020 ◽

Author(s):

Pieter-Jan Daems ◽

Y. Guo ◽

S. Sheng ◽

C. Peeters ◽

P. Guillaume ◽

...

Keyword(s):

High Frequency ◽

Failure Modes ◽

Measurement Data ◽

Wind Farms ◽

Frequency Measurement ◽

Operating Conditions ◽

Failure Data ◽

The World ◽

Operations And Maintenance ◽

History Of

Abstract Wind energy is one of the largest sources of renewable energy in the world. To further reduce the operations and maintenance (O&M) costs of wind farms, it is essential to be able to accurately pinpoint the root causes of different failure modes of interest. An example of such a failure mode that is not yet fully understood is white etching cracks (WEC). This can cause the bearing lifetime to be reduced to 5–10% of its design value. Multiple hypotheses are available in literature concerning its cause. To be able to validate or disprove these hypotheses, it is essential to have historic high-frequency measurement data (e.g., load and vibration levels) available. In time, this will allow linking to the history of the turbine operating data with failure data. This paper discusses the dynamic loading on the turbine during certain events (e.g., emergency stops, run-ups, and during normal operating conditions). By combining the number of specific events that each turbine has seen with the severity of each event, it becomes possible to assess which turbines are most likely to show signs of damage.

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Helicobacter pylori infection and its correlates among the patients of peptic perforation and gastric carcinoma

International Surgery Journal ◽

10.18203/2349-2902.isj20201862 ◽

2020 ◽

Vol 7 (5) ◽

pp. 1518

Author(s):

Subhendu Bikas Saha ◽

Sabyasachi Bakshi ◽

Tapas Mandal

Keyword(s):

Gastric Carcinoma ◽

High Frequency ◽

Age Group ◽

Morbid Condition ◽

Exclusion Criteria ◽

Chronic Alcoholic ◽

Female Ratio ◽

History Of ◽

Study Population ◽

H Pylori

Background: Presence of H. pylori infection was found associated with peptic perforation and gastric carcinoma. Present study tried to estimate the prevalence of H. pylori infection in those patients and to find out the correlates of H. pylori infection.Methods: After matching the inclusion and exclusion criteria, all cases of diagnosed peptic perforation and gastric carcinoma were taken for this prospective, single center, observational study.Results: Among the study population, gastric carcinoma was found in higher age group; whereas peptic perforation was found in lower age group; male and female ratio was 2:1 in both groups of patient. Laborer and housewives were mostly affected in both cases. Gastric carcinoma was more prevalent in urban residents, opposite was seen in peptic perforation. Most patients in two groups had no previous co-morbid condition. Use of NSAIDs was found in high frequency in both groups. Most of the patients were chronic alcoholic and chronic smoker, and most of them had history of taking spicy foods more than twice in a week.Conclusions: H. pylori infection was found in high frequency in both group of patients, and it was higher in peptic perforation. The study establishes the association of H. pylori with the gastric carcinoma and peptic perforation.

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