Showing papers by "Louisiana State University published in 1977"
TL;DR: In this article, a positive relationship was demonstrated for 27 locations between commercial yields of penaeid shrimp per area intertidal vegetation and latitude which can be described by the formula y = 158.7e-0.070(x) where y is kilograms/hectare and x is degrees latitude between 0 ° and 35 °.
Abstract: A positive relationship is demonstrated for 27 locations between commercial yields of penaeid shrimp per area intertidal vegetation and latitude which can be described by the formula y = 158.7e-0.070(x) where y is kilograms/hectare and x is degrees latitude between 0 ° and 35 °. The latitudinal gradient grossly parallels a gradient of heating-degree-days and is twice the slope of the probable rates of litterfall frown estuarine macrophytes. On a regional basis, the yields inshore are directly related to the area of estuarine vegetation whereas they are not correlated with the area, average depth, or volume of estuarine water. A short example is given to illustrate the utility of this analysis for the selection of alternative land-use decisions.
306 citations
TL;DR: In this paper, a self-consistent tight-binding calculation of the band structure of body-centered-cubic iron was performed using the Coulomb part of the crystal potential in the first iteration, constructed from a superposition of overlapping neutral-atom charge densities.
Abstract: Results of a self-consistent tight-binding calculation of the band structure of body-centered-cubic iron are reported. The basis set consisted of atomic wave functions for the $1s$, $2s$, $3s$, $4s$, $2p$, $3p$, and $4p$ states, expressed as linear combinations of Gaussian-type orbitals (GTO), and five individual GTO for each $3d$ state. The Coulomb part of the crystal potential in the first iteration was constructed from a superposition of overlapping neutral-atom charge densities; the atoms being in the $3{d}^{7}4{s}^{1}$ configuration. Exchange potentials for both spins were calculated utilizing the $X\ensuremath{\alpha}$ method. Self-consistent band structures were obtained for different values of the exchange parameter $\ensuremath{\alpha}$. Best results appear to be obtained for $\ensuremath{\alpha}=0.64$. In this case, 140 points in $\frac{1}{48}$ of the Brillouin zone (BZ) were used to determine the charge density. The resulting self-consistent potentials were then utilized to compute energy levels at 819 regularly spaced points in $\frac{1}{48}$ of the BZ. The results thus obtained are discussed and compared with other reported band-structure results for the same metal. The Fermi surface is analyzed in detail. The density of states has been computed. Magnetic and x-ray form factors are presented. The results are found to be in reasonably good agreement with experiment.
272 citations
TL;DR: Barium profiles at the Atlantic stations of the Geochemical Ocean Sections (GEOSECS) Program are remarkably similar to those for silicate and alkalinity as mentioned in this paper, and both barium and silica behave non-conservatively in basins with restricted circulation.
264 citations
TL;DR: The total spectrum of observed correlates of BP, resulting from the multiple regression analysis, suggests that the BP measured under basallike conditions increases as the child grows and is proportional to lean body mass and total body mass.
Abstract: Body height and body mass as determinants of basal blood pressure in children--The Bogalusa Heart Study. Am J Epidemiol 106:101-108, 1977. Risk factor variables for coronary artery disease were measured in a total biracial community study of 3524 children, ages 5-14 years. Anthropometric variables, serum lipids, and blood pressure (BP) were measured in a rigid randomized design. Blood pressure data were obtained with an automatic recording instrument that avoids excessive pressure readings in obese children by the use of an over-sized arm cuff bladder with a built-in infrasonic transducer. By reducing the anxiety of the child and by taking multiple readings, pressures were obtained that approached published basal levels. A multiple regression analysis showed that all measured variables could account for 39% of the systolic BP variation. Major determinants were based on weight (W) and height (H). The BP levels, when related to H and to a weight-height index (W/H3), suggest a strong influence of H and an additional influence of W/H3 on BP, both consistent and proportionate over the entire ranges of H and W/H3. The total spectrum of observed correlates of BP, resulting from the multiple regression analysis, suggests that the BP measured under basallike conditions increases as the child grows and is proportional to lean body mass and total body mass. Practical criteria for evaluating abnormal blood pressure levels in children should be based on normative values derived from body weight and body height rather than from age.
242 citations
TL;DR: In this paper, a study of the behavior of dissolved Ba during mixing of fresh and marine waters in a classic salt-wedge estuary was made, where much of the mixing was confined within the river channel.
172 citations
TL;DR: Vaginal smears were stained, observed microscopically, and found to correlate with perineal swelling, hormone levels, and laparoscopic observations, and with development of the ovarian follicle.
Abstract: Perineal swelling was correlated with changes in vaginal cytology and serum ovarian hormone levels and with development of the ovarian follicle. The average length of 66 menstrual cycles as seen in 12 mature baboons was 35.7±.66 days with a range of 25 to 47 days. Laparoscopic observations and photographic documentation of follicular development were made as early as 13 days prior to ovulation with the most rapid follicular maturation occurring 24 to 48 hours before ovulation. In 38.5% of the cycles ovulation occurred on the last day of maximal perineal tumescence with 26.9% of the ovulations occurring one day after initial detumescence. In 17.8% ovulations occurred two to five days prior to detumescence while the remaining 17.8% occurred two to three days following first observed detumescence. The mean progesterone level during the follicular phase was significantly less than that in the luteal phase, 1.6 and 6.7 ng/ml respectively (p<0.01). The level of estrogen detected during the periods of maximal tumescence was significantly higher (p<0.05) than that detected in the remainder of the cycle, 19.8 and 5.9 pg/ml respectively. Vaginal smears were stained, observed microscopically, and found to correlate with perineal swelling, hormone levels, and laparoscopic observations.
137 citations
TL;DR: In this article, standard climatological observations made between 1971 and 1974 at Moisant Airport, New Orleans, were organized into a calendar of eight synoptic weather types identified from the daily surface weather maps of the United States.
Abstract: Standard climatological observations made between 1971 and 1974 at Moisant Airport, New Orleans, have been organized into a calendar of eight synoptic weather types identified from the daily surface weather maps of the United States. The hourly data have been reorganized into tables representing monthly frequencies of weather types, mean properties at 0600 and 1500 CST, and relationships to precipitation. The climatic calendar and associated climatic properties by weather types represent climatic baseline inventories useful for evaluating favorable conditions for activities dependent upon weather such as construction and recreation, local and regional climatic variation by weather type and season, climatic variability through time, and the responses of environmental and biological processes and activities at the earth-atmosphere interface.
129 citations
TL;DR: If V is a vector space over a finite field F, the minimum number of cosets of k-dimensional subspaces of V required to cover the nonzero points of V is established by associating with each coset L of a subspace of V a polynomial whose roots are the points of L.
123 citations
TL;DR: Adenomatous polyps are a good epidemiologic indicator of colon cancer risk and their presence should be helpful in advancing from studies of the epidemiology of Colon cancer to the epidemiological of precursor lesions.
Abstract: Based on a study of the prevalence of intestinal polyps in New Orleans and on international comparisons, the following conclusions are reached. 1) There is a close parallelism in the epidemiology of colon cancer and adenomatous polyps. Both conditions are statistically associated with respect to geography, anatomic localization, socioeconomic class, migration experience and time trends. 2) The strength of the association favors the notion of a direct, positive correlation between multiplicity, size and atypia of polyps, and cancer risk, equivalent to "dose-effect". 3) The epidemiologic findings are coherent with other biologic facts derived from clinical, morphological and experimental studies. 4) Adenomatous polyps are a good epidemiologic indicator of colon cancer risk and their presence should be helpful in advancing from studies of the epidemiology of colon cancer to the epidemiology of precursor lesions.
111 citations
01 Jan 1977
105 citations
TL;DR: The isolate of Beggiatoa from Bernard clay, when reinoculated into soil treatments from pure culture, significantly reduced hydrogen sulfide levels in soils and increased oxygen release from rice plants, suggesting that it may be an element of wetlands plant ecosystems.
Abstract: Beggiatoa was obtained from six habitats, including four water-saturated soils from rice fields. The isolate of Beggiatoa from Bernard clay, when reinoculated into soil treatments from pure culture, significantly reduced hydrogen sulfide levels in soils and increased oxygen release from rice plants. Rice plants significantly increased Beggiatoa survival in flooded soils. Some hydrogen sulfide was necessary for survival of the Bernard clay isolate; high concentrations of hydrogen sulfide killed the Bernard clay isolate but were tolerated by a Crowley silt loam isolate from Eagle Lake, Texas. The results suggest that Beggiatoa may be an element of wetlands plant ecosystems.
TL;DR: Findings were interpreted as indicating that the SCL-90 has limited use with psychiatric inpatients at present, although it may be useful as a brief screening device for disposition and referral.
Abstract: Examined the convergent and discriminant validity of the SCL-90 in a group of 113 psychiatric inpatients and determined the degree of reactivity to several common response sets. The nine SCL-90 dimensions were found to correlate with analogous measures from other tests, and thus showed convergent validity, but were also found to correlate with nonanalogous measures, an indication of low discriminant validity. In addition, the dimensions correlated with the three MMPI validity scales, suggesting their reactivity to response bias. These findings were interpreted as indicating that the SCL-90 has limited use with psychiatric inpatients at present, although it may be useful as a brief screening device for disposition and referral.
TL;DR: Comparison of the clinical picture presented in syrup or fluid extract of Ipecac overdose and emetine toxicity in amebiasis treatment permits us to summarize the general characteristics ofIpecac alkaloid toxicity as involving primarily gastrointestinal, cardiovascular, and neuromuscular foci.
Abstract: The general effectiveness and safety of Ipecac syrup, per se, has not been questioned, but rather an attempt has been made to consolidate pertinent literature dealing with the toxic manifestations of Ipecac fluid extract. Ipecac contains both emetine and cephaeline and the toxicity of Ipecac fluid extract is consistent with reports on the toxicity of both compounds. The majority of the work has involved emetine since it is in higher concentration in Ipecac fluid extract than is cephaeline. Comparison of the clinical picture presented in syrup or fluid extract of Ipecac overdose and emetine toxicity in amebiasis treatment permits us to summarize the general characteristics of Ipecac alkaloid toxicity as involving primarily gastrointestinal, cardiovascular, and neuromuscular foci.
TL;DR: Although the PATS Inventory and the ASK Test as presently constructed may be clinically useful particularly with respect to parental counseling, continued research appears warranted to enhance their usefulness as research and clinical instruments.
TL;DR: It is concluded that the FEV 1 is the best test for evaluating the response to bronchodilators in patients and that use of body plethysmography and the FEF25–75% do not allow any more conclusions than can be made with theFEV 1 and FVC alone.
TL;DR: In this article, plant macrofossil and pollen assemblages incorporated in fluviatile terrace deposits in the study area are reexamined in light of the current stratigraphic understanding.
TL;DR: The results were used as measures of the concentration and distribution of organic detritus in the coastal waters of Caminada and Barataria bays, Louisiana, and the Gulf of Mexico as discussed by the authors.
TL;DR: The procedure for cricket rearing emphasizes ease of maintenance and consistency of results and is easily adapted to obtain crickets of known age of either sex in the last 2 instars or the adult stage.
Abstract: The only major requirement in our method is a small room in which all the crickets are housed at a temperature of 30.5°C. The diet is a finely ground, modified chick starter mash. Water is provided via inverted plastic vials in gravel-filled petri dishes. Collected eggs hatch in 13 days and hatchlings are reared in glass aquaria for the 1st 3 or 4 instars. The remaining instar s are kept in modified rat cages. Last instar females are picked each day from the appropriate agegroup of crickets and kept separately in reusable onegal cylindrical cartons. These methods are easily adapted to obtain crickets of known age of either sex in the last 2 instars or the adult stage. Cumulative aging is also possible by simply noting the days from hatch for a group of crickets. Freely available standing water is superior to cloggable wicks. Moderate water deprivation, overcrowding, or slight temperature changes may drastically affect the life cycle duration and physiological parameters of the house cricket. Our procedure for cricket rearing emphasizes ease of maintenance and consistency of results.
TL;DR: In this paper, the strength distribution for an arbitrary excitation is given in terms of a double expansion, and its sum rules by single expansions, in polynomials defined by the initial and final energy spectra.
TL;DR: A comparison of husbands and wives' preferences in 11 subdecisions of the automobile purchase decision revealed strong similarity in first choices but moderate discrepancy in total preference dist... as discussed by the authors, and showed that husbands' and wives preferences were similar in first choice but different in second choice.
Abstract: A comparison of husbands’ and wives’ preferences in 11 subdecisions of the automobile purchase decision revealed strong similarity in first choices but moderate discrepancy in total preference dist...
TL;DR: In this article, an iterative algorithm based on weighted-least-squares estimation theory is proposed to determine directly all standard parameters for a hypothesized model structure by repeatedly processing the armature and field current data of a sudden short-circuit test.
Abstract: Some applications of synchronous machine models with a desired structure require parameter values which are frequently not readily and satisfactorily obtainable from design data or field tests. An iterative algorithm based on weighted-least-squares estimation theory is proposed to determine directly all standard parameters for a hypothesized model structure by repeatedly processing the armature and field current data of a sudden short-circuit test. Results for a simulated salient-pole synchronous machine with damper winding are included, where the parameters X d , X' d ,X'' d ,X l , X q , X'' q , R a , T' do ,and T'' qo are readily identified in a few iterations with high accuracy.
TL;DR: In this article, a large number of data on the continental shelf and upper continental slope off the modern delta of the Mississippi river have been compiled; these data will be used to document the major types of slope instabilities.
Abstract: The improvement of sensors such as various high‐resolution seismic and navigational systems and side‐scan sonar, of offshore shallow‐water drilling techniques, and of laboratory analyses has allowed the marine geologist to make more accurate identifications and maps of the distribution of numerous types of marine sediment instabilities, as well as to determine the mechanisms responsible for their occurrence. A large number of data on the continental shelf and upper continental slope off the modern delta of the Mississippi river have been compiled; these data will be used to document the major types of slope instabilities. The continental shelf and slope off the modern Mississippi river delta display various types of sediment instability. High rates of sedimentation (up to 80 m per century), weak, high‐water‐content clays, and differential weighting of clay sediments characterize this region. The major types of sediment instabilities that have been documented include (a) Peripheral slumping, with ...
01 Jan 1977
TL;DR: In a 14-month period in 1973-74, several functional properties were studied in a swamp forest and lake system in Louisiana, including productivity of bottomland hardwood (BLH) and baldcypress-tupelo (CT), productivity of lake and bayou waters; hydrology; and carbon and nutrient export to the lower estuary as mentioned in this paper.
Abstract: During a 14-month period in 1973-74, several functional properties were studied in a swamp forest and lake system in Louisiana. The study area forms the upper drainage basin of the Barataria Bay estuary. Properties measured were: a) productivity of the two swamp forest components, bottomland hardwood (BLH) and baldcypress-tupelo (CT); b) productivity of lake and bayou waters; c) hydrology; and d) carbon and nutrient export to the lower estuary. Productivity of the BLH site was 800 g dry wt·m–2·yr–1 for stem biomass increase, 584 for litterfall, and 200 for understory production. Similar figures for CT were 500, 620, and 20. Total above-ground net productivity was 1584 for BLH and 1140 for CT. Net daytime photosynthesis (NDP) for the lake was 1418 g 02·m–2·yr–1 and nighttime respiration (NR) was 1868 (P/R = 0.76). For the bayous NDP was 316 and NR was 446 (P/R = 0.71). Water discharge from the basin is significant year-round except during the summer when evaporation equals precipitation. Annual export to the lower estuary (calculated from water discharge and materials concentrations) was 8016 metric tons of organic C, 1047 metric tons N, and 154 metric tons P. The greater part of this export occurred during the spring, corresponding to the spring peak in biological activity in the estuary.
TL;DR: This investigation compared the visual evoked responses (VERs) and reaction time (RT) performance of dyslexic boys and 24 controls at four different age levels to eliminate differences due to social or educational deprivation, gross sensory-motor handicaps, specific neurological deficiencies, or intellectual impairment.
Abstract: This investigation compared the visual evoked responses (VERs) and reaction time (RT) performance of 24 dyslexic boys and 24 controls at four different age levels (7, 9, 11, and 13 yrs). Prescreening and matching techniques were used to eliminate differences due to social or educational deprivation, gross sensory-motor handicaps, specific neurological deficiencies, or intellectual impairment. The VER was recorded from four scalp locations (O1, O2, P3, and P4) referenced to the vertex during a detection task in which subjects were required to respond to dim flashes occurring in a train of brighter flashes. An overall hemispheric asymmetry in VER amplitude (right > left) was observed in both experimental and control subjects. Dyslexics exhibited an increased amplitude to unattended stimuli and a slower RT to attended stimuli. Normals exhibited significant correlations between RT and VER latency, dyslexics did not. There were no significant VER-IQ correlations. The results are discussed in terms of an attentional deficit hypothesis.
TL;DR: During hibernation changes occurring in the bone suggest osteocytic osteolysis, which means minerals may be mobilized from bone for utilization elsewhere in the body to maintain a minimal metabolic level for surtival.
Abstract: The interradicular alveolar bones of the nonhibernating and hibernating ground squirrels were compared using laght and transmission electron microscopy. During hibernation changes occurring in the bone suggest osteocytic osteolysis. Minerals may be mobilized from bone for utilization elsewhere in the body to maintain a minimal metabolic level for surtival.
TL;DR: In fishes, the olfactory and gustatory systems of catfish differ in amino acid sensitivity, specificity and response characteristics, which could allow for the functional separation of the chemical senses in an aquatic environment.
Abstract: VERTEBRATES possess two principal systems, olfaction and taste, adapted to respond to peripheral chemical excitation. Olfaction in terrestrial vertebrates is the more acute chemosensory system, having lower thresholds to volatile stimuli than the gustatory thresholds to nonvolatile compounds1,2; thus, olfaction was termed the ‘distance’ sense and gustation the ‘contact’ sense. With fishes, however, chemical stimuli are present in the aqueous medium and it is difficult to distinguish between olfactory and gustatory stimuli or to explain the development of two chemical senses in the primitive aquatic vertebrates. Fishes exhibit important morphological distinctions between olfactory and gustatory systems both at the periphery and centrally3, and yet, in catfish, amino acids are the most effective stimuli known for both systems4,5. This sensory overlap does not reflect a simple duplication of receptor function, however, as the olfactory and gustatory systems of catfish differ in amino acid sensitivity, specificity and response characteristics, which could allow for the functional separation of the chemical senses in an aquatic environment.
TL;DR: Crassostrea virginica Gmelin were subjected to simulated tidal fluctuations of salinity, and the subsequent effects on osmotic and ionic composition of the pericardial fluid, body water and valve movements were investigated.
Abstract: Crassostrea virginica Gmelin were subjected to simulated tidal fluctuations of salinity, and the subsequent effects on osmotic and ionic composition of the pericardial fluid, body water and valve movements were investigated. Ambient salinity fluctuation patterns of 20-10-20‰, 15-10-15‰ and 10-5-10‰ were simulated during 24.8-h periods. An additional 10-5-10‰ S experiment was performed using a dilution water approximating the ionic composition of Mississippi River water with regard to Mg++, Ca++ and SO
4
=
, instead of deionized water. Finally the effects of a 2-week diurnal fluctuation pattern between 20 and 10‰ S were investigated with respect to pericardial fluid composition. Pericardial fluid osmolality, concentrations of Cl-, Na+, Mg++, K+, Ca++ and ninhydrin-positive substances (NPS) were analyzed periodically throughout all experiments. Pericardial fluid osmolality was slightly hyperosmotic as ambient water salinity decreased during a cycle, and then became slightly hyposmotic as ambient salinity increased. In the 2-week experiment, pericardial fluid osmolality tracked ambient seawater closely through Day 5, but became more intermediate between high and low seawater values as the experiment progressed. Similar patterns during fluctuations of salinity were observed for Na+, Cl-, Mg++ and Ca++. Pericardial fluid K+ levels did not track ambient seawater as closely as did other ions. The ionic composition of dilution water had little effect on the osmotic or ionic response of the oyster's pericardial fluid. Pericardial fluid NPS level varied inversely with salinity during the 20-10-20‰ cycle. During the longterm fluctuation experiment, NPS values gradually decreased over the 2-week period compared to constant salinity control values. Percent body water also varied inversely with ambient salinity. Solute movement accounted for most of the change in pericardial fluid osmolality during the simulated cycles with water movement responsible for 1 to 11%. Water movement contributed more to the change of pericardial fluid osmolality during the decreasing salinity phase than the increasing phase of a given cycle. During 20-10-20‰ S cycles, oyster valves remained open 56% of the time (n=23). In contrast, when salinity was abruptly changed from 20 to 10‰ within 5 min, valve closure occurred in 4.8±0.3 min (n=20). Valves did not reopen for 19.3±1.2 h (n=15).
TL;DR: In this paper, absorption and magnetic circular dichroism (MCD) spectra were obtained for the 7 F 6→5 D 4 transition of Tb3+ in crystalline Cs2NaTbCl6.
Abstract: Absorption and magnetic circular dichroism (MCD) spectra are reported for the 7 F 6→5 D 4 transition of Tb3+ in crystalline Cs2NaTbCl6. These spectra are interpreted in terms of a crystal-field ana...
TL;DR: A case of Garre's disease has been reported, which is atypical in that the patient presented with only a periosteal bone mass and a negative history of toothache, abscess, or trauma to the area.