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Ergot (sugary disease) incited by a Sphacelia sp. was observed on Sorghum bicolor (L.) Moench var. Sweet Leaf II at Leland and Pop-larville, MS, in October 1997. The disease was characterized by droplets of a thick, sticky, semi-transparent secretion similar to aphid honeydew. The caryopsis of infected florets was converted to relatively soft, chalky pink, tumescent, immature sclerotia (1.5 to 1.7 × 4 mm) with blunt ends. Abundant conidia (11 to 17 × 5 to 7 μm) were produced on stromatic tissue and in large numbers in the sugary secretion. This fungus is similar to that described by Zummo in West Africa (2). Velazquez-Valle et al. (1) recently reported the distribution of Claviceps africana Frederiksen, Mantle & de Milliano in the United States in 1997. The Sphacelia stage of the fungus found in Mississippi is similar to that reported from other areas of the U.S. Our report extends the range for this fungus, which is contiguous to those areas reported by Velazquez-Valle et al. (1). References: (1) R. Velazquez-Valle et al. 37th Annu. Mtg. Carib. Div., Am. Phytopa-thol. Soc., San Jose, Costa Rica, No. 77, 1997. (2) N. Zummo. 1984. Sorghum Diseases in West Africa. An Illustrated Text. USDA/USAID, Zaria, Nigeria.

Objective: To determine whether the rate of clinical progression in Huntington disease (HD) is influenced by the size of the CAG expansion.Methods: The dataset consisted of 3,402 examinations of 512 subjects seen through the Baltimore Huntington's Disease Center. Subjects were seen for a mean of 6.64 visits, with mean follow-up of 6.74 years. Subjects were administered the Quantified Neurological Examination, with its subsets the Motor Impairment and Chorea Scores, the Mini-Mental State Examination, and the HD Activities of Daily Living (ADL) Scale.Results: In an analysis based on the Random Effects Model, CAG length was significantly associated with the rate of progression of all measures except chorea and ADL. There was a significant interaction term between CAG length and disease duration for all measures except chorea. Further graphical exploration of the data supported these linear models and suggested that subjects at the low end of the expanded CAG repeat range may experience a more benign late course.Conclusions: CAG repeat length has a small effect on rate of progression that may be clinically important over time. Individuals with the shortest expansions appear to have the best prognosis. These effects of the CAG length may be relevant in the analysis of clinical trials.

Pearl millet (Pennisetum glaucum [L.] R. Br.) production in semi-arid regions is limited by poor seedling emergence that results in poor stand establishment and, low yield. Six pearl millet populations were created by divergent selection within the Tift #2 S-1 (TIFT2) pearl millet population for seedling root length in sand in the greenhouse or seedling root or coleoptile length in paper germination towels in the laboratory. The TIFT2 population (TIFT2) and the six selected populations were grown in the field in a randomized complete block design at Mississippi State, MS (MSU) and at Katumani and Kiboko, Kenya in 1991 and 1992. Populations were evaluated for seedling emergence and shoot height every 3 d for the first 15 d after planting. The greatest differences in emergence occurred at the most water-stressed locations in both years. The population selected for longer seedling root length in sand (LR-S) generally showed the highest field seedling emergence and shoot height during the first 9 d. ...

Pearl millet [Pennisetum glaucum (L.) R. Br.] production in semi-arid areas is primarily limited by poor seedling emergence and poor stands, which result in low yields. The objectives of this study were to measure selection response for seedling root length and coleoptile length, and to compare the effectiveness of greenhouse and laboratory screening procedures for these traits. Divergent phenotypic recurrent selection for seedling root length and coleoptile length was practiced within each of two populations, Tift #2 S1 (TIFT2) and Nebraska Early Dwarf Synthetic (NPM2). The parental and respective selected populations were evaluated in sand in the greenhouse and in paper germination towels in the laboratory. Significant genetic variation was found for seedling root length in the genetically diverse TIFT2 population, but not in the NPM2 population. The TIFT2 subpopulation selected for long seedling root length in sand had significantly longer seedling root length than the subpopulation selected for short seedling root length. Genetic variation for coleoptile length was high in both populations. There were significant responses to selection in the TIFT2 population for seedling root length evaluated in sand and coleoptile length evaluated in germination towels. Selection response for long seedling root length in the TIFT2 population was greater when root length was evaluated in sand than when evaluated in germination towels. Realized heritabilities of TIFT2 subpopulations selected for long and short seedling root length in sand were 0.23 and 0.29, respectively. Realized heritabilities of TIFT2 populations selected for long and short seedling root length in paper germination towels were 0.0 and 0.33, respectively. Sand was a better selection medium than germination towels. Realized heritabilities for long and short coleoptile length were 0.21 and 0.55, respectively, for the TIFT2 population. For the NPM2 population, realized heritabilities for long and short seedling root length were 0.60 and 0.0, respectively, in sand and 0.0 and 0.26, respectively, in germination towels. Realized heritabilities for long and short coleoptile length were 0.0 and 0.90, respectively, for the NPM2 population. Pearl millet coleoptile and seedling root lengths were heritable and further selection gains should be possible.

Genotypes of plant species need to be assessed for ability to grow with fairly severe acid soil constraints. Twenty pearl millet ( Pennisetum glaucum R. Br.) genotypes were grown on an ultisol (Typic Palehumult) with 60% Al saturation and on an oxisol (Tropeptic Haplustox) with 53% Al saturation in Colombia, South America, to determine the effects of acid soil factors on growth-and-yield-component traits. Five of the genotypes were also grown on the acid ultisol at 50% Al saturation. The mean grain-yields of the genotypes grown on both soils ranged from 2260 to 3820 kg ha −1 . Plants grown on the oxisol had slightly higher yields than plants grown on the ultisol. Grain yield, grain plant −1 , seed plant −1 and head length decreased, and days to flower, number of tillers, plant height, head diameter and seed weight were unaffected when plants were grown on the relatively severe acid soils. Pearl millet genotypes grew relatively well on the fairly severe acid soils.

To obtain crops tolerant to aluminum (Al) toxicity in acid soils, several methods have been used to screen different plant species and genotypes to this production constraint. Little is known about the effect of the method on genetic analyses and breeding method suggested. Three genetic studies were conducted to examine evaluation method on inheritance and gene action of sorghum [Sorghum bicolor (L.) Moench] to Al toxicity as measured by seedling dry matter production.

The most useful parental germplasm for developing acid-soil- (pH 4.0–5.5) tolerant maize, rice, sorghum and tropical forage populations has been native species and land races collected from regions with known low pH and associated problems. Field evaluation of parental germplasm and progeny is superior to controlled evaluation for single acid-soil associated stresses, such as aluminium (Al) toxicity. Field conditions are modified to reach a level of % Al saturation of CEC (for maize, 40–50%, for sorghum, 60–70%) such that susceptible lines are eliminated and tolerant survive. For rice and pastures, nutrients are added only to allow crop growth and original pH and Al saturation (80–95%) are unmodified. For sorghum and rice the most effective breeding approach is pedigree selection, whereas for maize a full-sib selection is most effective (14% yield improvement per cycle). Forage breeding is just beginning to move beyond evaluation and selection of collected germplasm and alternative breeding approaches are being analyzed. Additive genetic variance and additive x environmental interaction is very important in the cereals. For each species, replicated testing of progenies over a range of environments is the most reliable means of evaluation. There are no data to indicate a negative correlation between acid-soil tolerance and yield under fertile conditions. High yielding hybrids and inbred varieties are the objective for sorghum, whereas open pollinated varieties and hybrids are preferred for tropical maize, inbred varieties for rice, and vegetatively propagated or self-pollinated, self-seeding varieties for the forages. Commercial cultivars of acid-soil-tolerant forages, rice, maize and sorghum have been released in Latin America.

Although digoxin is effective in the treatment of patients with chronic heart failure who are receiving diuretic agents, it is not clear whether the drug has a role when patients are receiving angiotensin-converting-enzyme inhibitors, as is often the case in current practice.We studied 178 patients with New York Heart Association class II or III heart failure and left ventricular ejection fractions of 35 percent or less in normal sinus rhythm who were clinically stable while receiving digoxin, diuretics, and an angiotensin-converting-enzyme inhibitor (captopril or enalapril). The patients were randomly assigned in a double-blind fashion either to continue receiving digoxin (85 patients) or to be switched to placebo (93 patients) for 12 weeks. Otherwise, their medical therapy for heart failure was not changed.Worsening heart failure necessitating withdrawal from the study developed in 23 patients switched to placebo, but in only 4 patients who continued to receive digoxin (P0.001). The relative risk of worsening heart failure in the placebo group as compared with the digoxin group was 5.9 (95 percent confidence interval, 2.1 to 17.2). All measures of functional capacity deteriorated in the patients receiving placebo as compared with those continuing to receive digoxin (P = 0.033 for maximal exercise tolerance, P = 0.01 for submaximal exercise endurance, and P = 0.019 for New York Heart Association class). In addition, the patients switched from digoxin to placebo had lower quality-of-life scores (P = 0.04), decreased ejection fractions (P = 0.001), and increases in heart rate (P = 0.001) and body weight (P0.001).These findings indicate that the withdrawal of digoxin carries considerable risks for patients with chronic heart failure and impaired systolic function who have remained clinically stable while receiving digoxin and angiotensin-converting-enzyme inhibitors.

Benazepril hydrochloride is a new angiotensin-converting enzyme inhibitor. In a multicenter study, 206 patients with mild to moderate hypertension were randomized to receive benazepril at a dose of 2, 5, 10, or 20 mg, hydrochlorothiazide, 25 mg, or placebo once daily for 4 weeks. The 20 mg dosage of benazepril lowered blood pressure to a degree equal to that of 25 mg hydrochlorothiazide: -12.2/7.7 mm Hg and -13.4/-7.5 mm Hg, respectively. Hydrochlorothiazide proved to be more effective in black subjects. At lower dosage levels of benazepril (2, 5, and 10 mg), blood pressure reduction was not significantly different from that with placebo. In those patients who failed to achieve goal diastolic blood pressure of less than 90 mm Hg with monotherapy after 4 weeks, the addition of open-label hydrochlorothiazide (25 mg/day) to benazepril, hydrochlorothiazide, or placebo produced a substantial additional decrease in blood pressure over a 2-week period. No definite adverse effects on hematologic measurements, serum biochemistry test results, or urinalyses were noted. Subjective adverse experiences were common in all groups but except in three or possibly four instances were not considered causally related to the study drug.

Information is limited on genotypic differences for and genetic control of mineral element composition in sorghum [Sorghum bicolor (L.) Moench] grown on acid soils. This study was conducted to better understand variability of Al, N, Mg, Si, P, S, K, Ca, Mn, Fe, and Zn concentrations in 40 sorghum hybrids and their 14 parents grown in the field on an Ultisol (Typic Palehumult) in Colombia, South America. Both male and female parents and hybrids grown at 67 and 43% Al saturations differed extensively in mineral element concentrations. Significant male and female effects on the hybrids were found for most mineral elements. Male × female effects were rarely significant. Significant differences between parents and hybrids were observed for N, Mg, Si, Ca, Mn, Fe, and Zn at 67% Al saturation, and for Al, Si, and Ca at 43% Al saturation.

Inheritance of acid-soil tolerance (generally considered Al-toxicity tolerance) in sorghum [Sorghum bicolor (L.) Moench] is not clear. Forty F1 sorghum hybrids and their 14 parents were grown two seasons in the field at relatively high (67 and 71%) and low (43 and 42%) Al saturations on an acid Ultisol in Colombia, South America to evaluate the effects of acid soil on agronomic component traits and to better understand inheritance of acid-soil tolerance of sorghum. For plants grown at the high Al saturation levels, hybrids from acid-soil tolerant [AS-T] × acid soil-sensitive [AS-S] crosses were as tolerant as hybrids from AS-T × AS-T crosses which were as tolerant as their AS-T parents. Hybrids from AS-S × AS-S crosses were all sensitive to the acid-soil stress conditions. General combining ability (GCA) and specific combining ability (SCA) effects were significant for acid-soil tolerance, and GCA effects were more important than SCA effects. Significant GCA and SCA effects were detected for grain yield and number of roots at the low Al saturation level. Additive genetic effects in these genotypes were important for acid-soil tolerance rating, grain yield, and number of roots at the high Al saturation level.

The adaptation of plants to acid soil conditions may be associated with mineral elements taken into plants. Leaf mineral element concentrations were determined in sorghum (Sorghum bicolor (L.) Moench) and pearl millet (Pennisetum glaucum (L.) R. Br.) genotypes grown on an acid ultisol (pH 4.0, 60% Al saturation) to better understand mineral element concentrations that might be associated with species and genotypic differences to tolerate acid soil conditions. Sorghum genotypes showed a broad range in grain yield while all pearl millet genotypes had relatively good grain yields when grown on the acid soil. Leaf concentrations of Si, Ca, Mg, S, and Cu were higher; P, K, and Al were lower; and N, Mn, Fe and Zn were similar in pearl millet when relative comparisons were made with sorghum. The relatively high leaf concentrations of Ca, Mg, and especially Si in pearl millet may have contributed to its ability to yield well on the acid soil.

Mineral element deficiencies and toxicities are common problems associated with sorghum [Sorghum bicolor (L.) Moench] production on acid soils. To better understand some of the mineral element problems and the analysis of plant tissue of sorghum plants grown on acid soils, four sorghum genotypes were grown on an acid Oxisol at Carimagua, Colombia limed with dolomite at 2 and 6 Mg ha‐1. Samples for mineral element analyses were obtained from leaves at different positions on the four genotypes. Concentrations of P and Mg were highest in the flag leaf (Leaf No. 1) and decreased as the position on the plant declined from the top of the plant for plants grown at 2 Mg lime ha‐1. Similar decreases in P, Mg, K, and Zn concentrations occurred in plants grown with 6 Mg lime ha‐1. Concentrations of Ca, S, Si, Mn, Fe, Cu, and Al increased as leaf position declined from the flag leaf for plants grown at 2 and 6 Mg lime ha‐1. The higher lime supply enhanced Ca and reduced Mn and Fe concentrations in leaves. Di...

Silicon fertilization has been shown to alleviate Mn and Al toxicities in some plants. Experiments were conducted to assess the role of different Si levels on the alleviation of Mn and Al toxicity symptoms and on dry matter yields of sorghum [Sorghum bicolor (L.) Moench] grown in nutrient solutions with toxic levels of Mn and Al. Silicon concentration as high as 1780 μM had no detrimental effects on dry matter yields. At high Si levels (2670 and 3560 μM), shoot dry matter yields decreased, but root dry matter yields did not. Plants grown with 3600, 5400, and 7200 μM Mn showed marked visual toxicity symptoms in shoots but no effects on roots, even though root dry matter yield decreased more than shoot dry matter yield. The toxicity symptoms and the dry matter yield reductions caused by 3600 and 5400 μM Mn were partially alleviated by 1780 and 3560 μM Si, whereas no Si level overcame the severe effects induced by 7200 μM Mn. Plants grown with high Al (296 μM) had reduced root dry matter yields. Sil...

Studies were conducted to determine mineral element concentrations in leaves of sorghum [Sorghum bicolor (L.) Moench] genotypes that were tolerant and susceptible to acid soil conditions, and to assess imbalances and changes in mineral elements in these genotypes grown at 60 (relatively severe Al stress, pH 4.1) and 40% (less severe Al stress, pH 4.6) Al saturation on an acid ultisol in Colombia, South America. Leaf concentrations of S, K, Al, Mn, and Fe were lower and concentrations of Ca and Si were higher in tolerant genotypes when plants were grown at 40 compared to 60% Al saturation. Susceptible genotypes had higher dry matter yield and leaf concentrations of Ca and Si, and lower concentrations of Mg, Al, Mn, Fe, and Zn when plants were grown at 40 compared to 60% Al saturation. At 60% Al saturation tolerant genotypes had higher dry matter yields and concentrations of Ca and Si and lower concentrations of P, S, Al, and Fe than susceptible genotypes. At 40% Al saturation, tolerant genotypes h...

Exercise-induced changes in the plasma levels of propranolol and noradrenaline were determined in nine volunteers. Total plasma propranolol levels were increased during submaximal treadmill exercise, with exercise-induced increments of 13 +/- 4% at 4 h after the last dose, 18 +/- 7% at 9 h and 41 +/- 5% at 16 h. Exercise-induced increments in plasma propranolol were observed after single as well as repeated doses. During exercise, increments in plasma propranolol were correlated temporally with changes in plasma noradrenaline. Exercise-induced increments in plasma noradrenaline were greater during propranolol administration than during placebo periods. The changes in plasma propranolol concentration during exercise may reflect a redistribution of propranolol at its site(s) of action.

Genetic manipulation of crops to tolerate mineral stresses is a practical approach to improve productivity of tropical acid soils. Both acid soil tolerant (AS-T) and susceptible (AS-S) sorghum [Sorghum bicolor (L.) Moench] genotypes were grown in the field on an acid ultisol at Quilichao, Colombia, South America at 60% (60-Al) and 40% (40-Al) Al saturation to evaluate plants for growth and yield traits.

Silicon can help alleviate Mn toxicity in some plants. Growth chamber studies were conducted to assess the effect of Si on growth and mineral element composition in sorghum. [Sorghum bicolor (L.) Moench] grown in nutrient solutions with excess Mn. Treatments were all combinations of 18, 1800, 3600, and 7200 uM Mn and 0, 890, 1780, and 3560 uM Si using two genotypes. High Mn levels decreased dry matter yields which were partially overcome by the addition of Si, especially at the 1800 and 3600 uM Mn levels. Silicon had no deleterious effects on plant growth at the levels used. Increased levels of solution Mn decreased shoot concentrations of Si, K, Ca, Mg, Zn, and Cu; increased shoot concentrations of Mn and P; decreased root concentrations of K and Mg; and increased root concentrations of Mn, Si, P, Fe, Zn, and Cu. Total uptake of mineral elements by shoots and roots decreased in plants grown with high Mn because of decreased plant growth. Increasing Si levels in solution decreased shoot concentra...

Sorghum [Sorghum bicoior (L.) Moench] genotypes show large differences in dry matter and yield when grown on many tropical acid soils. The objective of this study was to determine differences in mineral element concentrations in sorghum genotypes grown on an acid oxisol limed with 2 and 6 Mg dolomitic limestone ha‐1 in Colombia, South America. Fifty genotypes showed differences in dry matter yield and concentrations of P, K, Ca, Mg, S, Si, Al, Mn, Cu, and Zn. Liming did not change low, high, and mean leaf concentrations of P, K, Mg, S, and Cu for the genotypes. Concentrations of Al, Mn, and Fe in the genotypes were higher in leaves of plants grown at 2 (pH 4.5 and 62% AT saturation) than at 6 Mg lime ha‐1 (pH 4.8 and 34% Al saturation). At the 6 Mg ha‐1 lime rate, leaf concentrations of Ca and Si increased. Silicon may have reduced the effects of toxic Al, and possibly toxic Fe. Genotypes showed sufficient variability in mineral element concentrations that selection for improved values of these t...

A helium gun was used to propel metal projectiles against targets of the same materials. Pressures produced by impact were varied by varying projectile velocities. The method produced pressures up to somewhat over 100 kbar, thus overlapping the lower part of the range of pressures which can be produced by detonation of high explosives. Of particular interest was the range of pressures intermediate between the highest which can be produced statically and the lowest which can be produced by explosives.A condenser micrometer was used to detect motion of the free surface of the target. This method permitted examination of the motion in greater detail than could reasonably be accomplished by other methods which have been used. Elastic and plastic waves were observed in iron and in bismuth. Assuming the Rankine‐Hugoniot shock conditions, pressures and compressions were computed. Pressure‐compression data for iron were obtained for intermediate pressures not previously investigated. Phase transitions in bismuth ...

A field screening procedure to evaluate a large portion of the sorghum [Sorghum bicolor (L.) Moench] world collection for tolerance to Al-toxic. low base status acid soils was developed that is now being employed in tropical South America. An Ultisol at Quilichao, Colombia, South America, with 63% Al-saturation, had Al-toxicity levels sufficient to kill sensitive sorghum genotypes, but not too high to prevent tolerant genotypes from producing reasonable yields of grain. Using soil classification maps of Africa to trace locations where particular genotypes were originally collected. genotypes were systematically selected for testing from areas with highly acid soils. The greatest genetic diversity in sorghum for Al tolerance might be expected to be found in the tropical areas with high percentages of acid soils. Higher percentages of sorghum lines in the tolerant and moderately tolerant category were selected from the acid soil areas in Kenya and Uganda than from the other African countries.

The effects of single oral and intravenous doses of propranolol on blood pressure and hemodynamics were measured in normal volunteers. Systolic and diastolic blood pressure decreased 10% within 3 hours after the oral dose and by 3%-5% after the intravenous dose. Cardiac output decreased 16% after the intravenous dose and 10% after the oral dose. Total peripheral resistance transiently increased by 23% after the intravenous, but not after the oral dose. Change in mean arterial pressure was positively correlated with change in total peripheral resistance after both the oral and intravenous doses. In contrast, change in mean arterial pressure was negatively correlated with change in cardiac output after the intravenous dose. Single oral and intravenous doses of propranolol lowered blood pressure within 3 hours after administration, and the reduction was correlated with change in total peripheral resistance and not with change in cardiac output. At least part of the adaptation in peripheral resistance occurs within the first 3 hours after both oral and intravenous single doses of propranolol.