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J B Welch

Publications and source records attributed to J B Welch.

25 records · Page 2Linked to original sources
PubMed1989

Conceptual model for the use of aerial color infrared photography by mosquito control districts as a survey technique for Psorophora columbiae oviposition habitats in Texas ricelands.

Two photographic missions per year are recommended to provide information on land-use and mosquito oviposition habitats. A winter mission, following a rain, will-provide a view of low areas within fields which may be obscured by summer vegetation. A summer mission will provide current land-use and crop distribution information and may show plant stress conditions due to excessive soil moisture. An aerial color infrared photographic survey with directed ground verification should result in a substantial savings in cost and increased efficiency in surveillance of mosquito producing habitats over ground survey techniques currently employed by mosquito control districts.

Animals↗
PubMed1987

Oviposition habitats of Psorophora columbiae in soybean fields of a Texas riceland agroecosystem.

Soil samples were collected over a 21/2-year period from microhabitats in fields planted to soybeans in Chambers County, TX, to study the oviposition behavior of Psorophora columbiae. An analysis of egg collection data gathered from the processing of 1,098 soil samples suggested that, during wet years, Ps. columbiae eggs tend to be scattered throughout soybean fields. During dry years, a greater abundance of eggs occur in the low areas of these types of fields. The data also suggested that oviposition by Ps. columbiae is concentrated in soil near the base of soybean plants rather than in open furrows between the rows of plants.

Agriculture↗
PubMed1986

A case of bupropion-induced seizure.

Bupropion is a novel new antidepressant without the undesirable anticholinergic, cardiotoxic, sedative, or sexual side effects of other available antidepressants. However, like many other antidepressants, there is a small risk that patients on bupropion may develop a seizure even at moderate doses and moderate blood levels and even in the absence of any premorbid history or other predisposing factors to epilepsy. The report presents the case of a 25-year-old woman with a 12-year history of agoraphobia and panic attacks treated with bupropion in a research protocol. She was in good physical health, with normal physical and neurological examination, and normal complete blood count, serum mineral analysis-12, and urinalysis laboratory values. She had no premorbid history of epilepsy or neurological illness, nor any other known predisposing factors to epilepsy. On day 28 of the study, immediately after her dose of bupropion was increased from 450 to 600 mg/day, she had a generalized convulsion with tonic and clonic phases, loss of consciousness, and postictal confusion that was reliably witnessed by several observers. The EEG abnormality had cleared 15 days later. Further EEGs after 4 weeks and 10 weeks were normal. Five years later she remains seizure-free, off all antiseizure medication, and without any further complications from this incident. This seizure occurred at a modest blood level of bupropion (83 ng/ml) and at a dose not considered excessive (600 mg/day). Other confounding organic and neurological illness or use of other medication was carefully and systematically ruled out, leaving the bupropion as the most likely explanation for her seizure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Occurrence of Psorophora columbiae eggs in different field types comprising a Texas riceland agroecosystem.

Soil samples (3,258) were collected from soybean fields, rice fields and permanent pastures in Chambers County, TX over a 2 1/2-year period and examined for the presence of Psorophora columbiae eggs. Eggs occurred more frequently and in greater numbers in samples taken from soybean fields than in samples from either rice fields or permanent pastures during the summers of 1979 and 1981 when there was heavy rainfall in the study area. Under dry conditions, as during the summer of 1980, the frequency of egg occurrence and abundance increased in samples taken from rice fields. However, egg occurrence and abundance in soybean field samples still remained relatively high even during this particular year.

Agriculture↗