67 research outputs found
Congenital Abnormalities Associated with Vitamin E Malnutrition
Congenital abnormalities are known to occur occasionally in man and farm livestock, and frequently in laboratory animals subjected to certain types of experimentation. A high percentage of the cases are fatal to the young depending on the nature and severity of the complications. In many instances death of the affected young occurs during pregnancy or parturition. Should the feti survive parturition death usually follows shortly thereafter. Extended survival occurs in a small percentage of young and these are mildly to severely handicapped in one or more of a multiplicity of ways. There are many causes of congenital abnormalities. Some are manifestations of disturbances to the germ plasm, while others are strictly somatic. In this report we are concerned with what might be termed disturbances to biochemical mechanisms of embryonic development induced by faulty nutrition. When essential nutrients are either absent from the ration or present in critically insufficient amounts, mild to severe disturbances usually occur to the feti during embryonic development
Determining the physiological response of a subtropical seagrass, Thalassia testudinum, to salinity stress using pulse amplitude modulated (PAM) fluorometry
I investigated how photosynthetic performance of Thalassia testudinum changed along a naturally occurring salinity gradient in Florida Bay, and to laboratory controlled hyper and hypo-osmotic stress. I found significant differences between sites in Florida Bay for yield ratios (Y and Fv/Fm); however, this difference does not seem to be based on the salinity regime, since sites with the greatest salinity range were not significantly different from the site with the lowest salinity range. Laboratory results showed declines in the minimum and maximum fluorescence values after a gradual ramping-up of salinity and after long-term exposure to a sustained drop in salinity, but these declines were not seen with the Y and Fv/Fm ratios.
Caution should be used when drawing conclusions about physiological stress from results obtained by PAM fluorometry, as acclimation may play a large role in the fluorescence response, limiting the use of this technique
Relationship of Time of Therapy to Teratogeny in Maternal Avitaminosis E
The literature concerning teratogeny that is attributable to faulty nutrition of laboratory induced origin was reviewed in a previous publication (Thomas and Cheng: 1952). Any review of this subject leads to the conclusion that there are numerous conditions of nutritional insufficiency which produce congenital abnormalities. Until reported recently (Thomas and Cheng, 1952) none had been ascribed to avitaminosis E. The usual abnormality in reproduction which prevails among pregnant rats in an advanced state of avitaminosis E is fetal resorption. Adequate vitamin E therapy administered promiscuously is not sufficient to circumvent reproductive difficulties. Timing of therapy is an exceedingly important limiting condition. Therapy that is adequate when given during the first week of gestation in the rat frequently will fail if delayed until the second and third weeks of gestation. When given during the second week uterine responses will be variable. Thus, in a single uterus some feti will be resorbed, others will have developed congenital abnormalities, and still others will appear externally morphologically normal. When therapy is given during the third week the embryological contents of the uterus will be partially or completely resorbed. The purpose of this report is to show more specifically than was possible at the time of our original announcement (Thomas and Cheng, 1952) the relationship of time of therapy to incidence of teratogeny in nutritional avitaminosis E. Also, data are presented summarizing the incidence of the different types of abnormalities thus far observed which are a part of this syndrome
Biomass and Productivity of Thalassia testudinum in Estuaries of the Florida Panhandle
Thalassia testudinum often dominates seagrass meadows of the Florida panhandle but few measurements of productivity, biomass, density, turnover or leaf area index in this region have been made. We targeted 5 estuaries located at similar latitudes, 30⁰ ± 0.3⁰N: Big Lagoon, Santa Rosa Sound, St. Andrew Bay, St. Joseph Bay, and St. George Sound. This study was one component of a collaborative partnership of state and local researchers examining factors preventing recovery in panhandle estuarine areas that had historically contained seagrass in the 1940s and 1950s. Measurements were made twice in 2016, once in June and then again in summer or fall, except in Santa Rosa Sound where measurements were made 3 times. In the estuaries sampled for the second time in July or August, aboveground productivity was greater than in June. St. Joseph Bay had the highest aboveground productivity (4.3 g/m2/d) and 1—sided leaf area index (4.2) while St. George Sound had the lowest values (0.41 g/m2/d and 1.0). Principal component analysis suggested that St. Andrew Bay, Big Lagoon and Santa Rosa Sound were the most similar, with higher values for shoot densities and leaf turnover and lower salinities and watershed:water ratios. St. Joseph Bay had high aboveground productivity and salinity, and low turbidity. St. George Sound had low aboveground productivity, high total suspended solids and the highest watershed:water ratio. These baseline productivity estimates will be useful to assess the success of restoration efforts targeting seagrasses in the Florida panhandle and evaluate impacts of climate change on seagrasses
The Lantern Vol. 7, No. 3, June 1939
• Commencement Sonnet • Largo Appassionato • More Sonnets to Earth • Vladimir • Abe Lincoln in Illinois • Dark Lives • Enter Mr. Smithingham II • A Character is Sketched • Sonnet • Out of the Dawn • Wistaria • Poem Without a Name • You Have Loved the Nighthttps://digitalcommons.ursinus.edu/lantern/1018/thumbnail.jp
The Lantern Vol. 7, No. 1, December 1938
• The Greatest Gift of All • Peace • Two Bums • October Paints the Valleys • Have the Notes Died? • America\u27s Defeatism Complex • Tahiti Jacques • When We Take Heed of Life • From The Sky Image • Still Moments • Noel • Foreign Hills • Just Beforehttps://digitalcommons.ursinus.edu/lantern/1012/thumbnail.jp
The Lantern Vol. 4, No. 1, December 1935
• A Challenge to All • The Tree • College With a Purpose • Midnight Clouds • Exultation • Pagan Festival • Ah Childhood! • From Brain to Brawn • Pictures in the Sky • Winds • In Absolution • Clouds in a Hot, Red Sky • Out of Douche and Latin • Satan Calls a Conference • Emptiness • A Portly Gentleman Intrudeshttps://digitalcommons.ursinus.edu/lantern/1014/thumbnail.jp
The Lantern Vol. 7, No. 2, March 1939
• Editorial • Easter Eggs • Fever • Sonnets to the Planet We Call Earth • Asking Her Father • New Hampshire Ghost Story • Mary • On Approaching Death • On Turning Over a New Leaf • In Defense of Americanism • What is this Love? • Martyrs of Progress • Recurring • Splintershttps://digitalcommons.ursinus.edu/lantern/1013/thumbnail.jp
- …