481 research outputs found
Organic Toxicity
In recent years there has been much discussion on the subject of organic matter toxicity and its relation to the severity of black root rot of tobacco. Organic matter toxicity is due to or at least related to toxins produced during organic matter decomposition
Plant Beds
Due to the occurrence of blue mold and manganese toxicity in some of the plant beds this last spring, it is probably advisable for all growers to select a new site for the 1964 crop.
Blue mold is a fungus disease which sometimes causes severe damage to tobacco seedings just prior to setting time. The fungus will produce heavy-walled spores on the dying or dead leaves. These spores are capable of remaining in the soil at least a year and attacking the next crop of plants if the same site is used again for tobacco plants
A New Black Shank Resistant Hybrid
Seed of a new black shank resistant burley hybrid will be available to growers in 1964. This hybrid is especially for farmers who cannot rotate their tobacco land and . thus, are forced to set their crop in a black shank infested field. The hybrid is a cross between two black shank resistant varieties, MS L8 and Burley 37. The female parent , MS L8, carries black shank resistance from a wild relative of tobacco
Calcium Deficiency Symptoms in Burley Tobacco
Calcium is an element required by all higher plants in relatively large quantities. It appears to be closely related to the formation of buds and flowers.
Calcium is usually available in sufficient quantities in Kentucky soils to produce a normal crop of tobacco. However, when certain varieties of burley tobacco commence to bloom and produce suckers, the tips of the calyx lobes of the flowers may turn brown and die and the edges of the small leaves of the suckers may be necrotic, resulting in irregularly shaped sucker leaves. In severe cases the apical bud may be killed. These calcium deficiency symptoms are most often observed during periods of stress such as protracted dry periods. This condition has been found to be heritable and is apparently caused by the improper utilization by the plant rather than the lack of calcium in the soil
Fall Treatment of Tobacco Beds with Methyl Bromide
Treating tobacco beds with methyl bromide for the purpose of killing weed seed has become very popular in recent years. The gas is effective except on the seed of white clover and when the soil temperature is below 50° F
A Burley Tobacco Variety-Management Study in 1966-67
A management study was designed to investigate the desirability of two management systems emphasizing (1) yield and (2) quality and a third system (3) aimed at achieving an acceptable level of both yield and quality. (These are hereafter referred to as the high yield, quality, and yield and quality systems, respectively.)
Two varieties, Burley 21 and Ky 10, were grown under the three management systems (outlined in Table 1) in 1/4 acre non-replicated plots at five locations in Kentucky in 1966 and at seven locations in 1967. A three-year or older sod was selected at each location. Phosphorus and potassium were applied in all systems at rates based on soil tests. Applications were sufficiently large so that these elements would not be limiting factors in plant growth
Delayed diagnosis of cystic fibrosis associated with R117H on a background of 7T polythymidine tract at intron 8
AbstractWe report late diagnoses of cystic fibrosis (CF) in two men aged 61 and 65 years. At the time of presentation, both patients had significant pulmonary disease. In each case two CFTR gene mutations were identified, including R117H on a background of a poly T genotype of 7T/9T. Patients with two identified CFTR mutations which include the R117H/7T anomaly should be followed up routinely as they remain susceptible to severe lung disease
Factors in perioperative care that determine blood loss in liver surgery
AbstractObjectivesExcessive blood loss during liver surgery contributes to postoperative morbidity and mortality and the minimizing of blood loss improves outcomes. This study examines pre- and intraoperative factors contributing to blood loss and identifies areas for improvement.MethodsAll patients who underwent elective hepatic resection between June 2007 and June 2009 were identified. Detailed information on the pre- and perioperative clinical course was analysed. Univariate and multivariate analyses were used to identify factors associated with intraoperative blood loss.ResultsA total of 175 patients were studied, of whom 95 (54%) underwent resection of three or more segments. Median blood loss was 782ml. Greater blood loss occurred during major resections and prolonged surgery and was associated with an increase in postoperative complications (P= 0.026). Peak central venous pressure (CVP) of >10cm H2O was associated with increased blood loss (P= 0.01). Although no differences in case mix were identified, blood loss varied significantly among anaesthetists, as did intraoperative volumes of i.v. fluids and transfusion practices.ConclusionsThis study confirms a relationship between CVP and blood loss in hepatic resection. Intraoperative CVP values were higher than those described in other studies. There was variation in the intraoperative management of patients. Collaboration between surgical and anaesthesia teams is required to minimize blood loss and the standardization of intraoperative anaesthesia practice may improve outcomes following liver surgery
DNA Renaturation at the Water-Phenol Interface
We study DNA adsorption and renaturation in a water-phenol two-phase system,
with or without shaking. In very dilute solutions, single-stranded DNA is
adsorbed at the interface in a salt-dependent manner. At high salt
concentrations the adsorption is irreversible. The adsorption of the
single-stranded DNA is specific to phenol and relies on stacking and hydrogen
bonding. We establish the interfacial nature of a DNA renaturation at a high
salt concentration. In the absence of shaking, this reaction involves an
efficient surface diffusion of the single-stranded DNA chains. In the presence
of a vigorous shaking, the bimolecular rate of the reaction exceeds the
Smoluchowski limit for a three-dimensional diffusion-controlled reaction. DNA
renaturation in these conditions is known as the Phenol Emulsion Reassociation
Technique or PERT. Our results establish the interfacial nature of PERT. A
comparison of this interfacial reaction with other approaches shows that PERT
is the most efficient technique and reveals similarities between PERT and the
renaturation performed by single-stranded nucleic acid binding proteins. Our
results lead to a better understanding of the partitioning of nucleic acids in
two-phase systems, and should help design improved extraction procedures for
damaged nucleic acids. We present arguments in favor of a role of phenol and
water-phenol interface in prebiotic chemistry. The most efficient renaturation
reactions (in the presence of condensing agents or with PERT) occur in
heterogeneous systems. This reveals the limitations of homogeneous approaches
to the biochemistry of nucleic acids. We propose a heterogeneous approach to
overcome the limitations of the homogeneous viewpoint
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