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Background For the fixation of displaced midshaft clavicular fractures different plates are available, each with its specific pros and cons. The ideal plating choice for this lesion remains subject to ongoing discussion. Reconstruction plates are cheap and easily bendable, but their strength and stability have been questioned. The aim of this study was to evaluate the failure rate of reconstruction plates in the fixation of clavicular fractures. Materials and methods A multicenter, retrospective cohort study of all consecutive patients with a displaced, midshaft clavicular fracture (Robinson type 2a/2b) treated with a 3.5-mm reconstruction plate between 2006 and 2013 were evaluated. The primary outcome measure was reoperation rate due to implant failure. Secondary outcome measures were nonunion, symptomatic malunion and elective plate removal. Results One hundred and eleven patients were analyzed. During a median follow-up of 8 months, 14 patients (12.6%) had implant failure, of which 7 (6.3%) required a reoperation. Three nonunions (2.7%) and no symptomatic malunions occurred. Plate removal was indicated in 37.8% of patients because of implant irritation. Discussion The incidence of reoperation due to implant failure following clavicular plate fixation with a reconstruction plate is 6.3%. Although comparison with other plate types is difficult since rates in literature vary greatly, reoperation rates in other plates are reported around 2–3%, suggesting that reconstruction plates have a higher incidence of implant failure warranting reoperation. Therefore, especially in patients with known risk factors for complications (e.g. smoking, osteoporosis, comminuted fractures), a stronger plate than a reconstruction plate should be considered. Level of evidence Level IV. Retrospective study.

Glass melts in the system Fe 2 O 3 /FeO/CaO/Na 2 O/B 2 O 3 were prepared from the raw materials, by firstly reducing them by flushing with nitrogen and subsequently roller quenching. The flakes obtained had a thickness of around 150 μm and were thermally treated at temperatures in the range from 550 to 620 °C. X-ray diffraction gave evidence of the occurrence of nanocrystalline magnetite. Magnetization measurements at room temperature show ferromagnetic behaviour and no hysteresis. Temperature-dependent measurements showed a monotonic decrease of the saturation magnetization with temperature, and a Curie temperature of 553 °C. The primary mean particle core diameter is around 10 nm after annealing at 570 °C.

Background For the fixation of displaced midshaft clavicular fractures different plates are available, each with its specific pros and cons. The ideal plating choice for this lesion remains subject to ongoing discussion. Reconstruction plates are cheap and easily bendable, but their strength and stability have been questioned. The aim of this study was to evaluate the failure rate of reconstruction plates in the fixation of clavicular fractures. Materials and methods A multicenter, retrospective cohort study of all consecutive patients with a displaced, midshaft clavicular fracture (Robinson type 2a/2b) treated with a 3.5-mm reconstruction plate between 2006 and 2013 were evaluated. The primary outcome measure was reoperation rate due to implant failure. Secondary outcome measures were nonunion, symptomatic malunion and elective plate removal. Results One hundred and eleven patients were analyzed. During a median follow-up of 8 months, 14 patients (12.6%) had implant failure, of which 7 (6.3%) required a reoperation. Three nonunions (2.7%) and no symptomatic malunions occurred. Plate removal was indicated in 37.8% of patients because of implant irritation. Discussion The incidence of reoperation due to implant failure following clavicular plate fixation with a reconstruction plate is 6.3%. Although comparison with other plate types is difficult since rates in literature vary greatly, reoperation rates in other plates are reported around 2–3%, suggesting that reconstruction plates have a higher incidence of implant failure warranting reoperation. Therefore, especially in patients with known risk factors for complications (e.g. smoking, osteoporosis, comminuted fractures), a stronger plate than a reconstruction plate should be considered. Level of evidence Level IV. Retrospective study.

Populations of copper-resistant (Cu r ) strains of Xanthomonas campestris pv. vesicatoria were monitored in the field on nonsymptomatic tomato leaflets treated with copper or with a copper and mancozeb mixture over three and four seasons, respectively. Copper and a combination of copper and mancozeb reduced epiphytic populations of X. c. vesicatoria, compared to those in the untreated control. Populations of X. c. vesicatoria on leaflets receiving copper and the copper-mancozeb combination differed significantly in only one of three seasons. A positive correlation was observed between epiphytic populations and disease severity (...)

Foliar-bract calcium (Ca) sprays and fertilization practices that altered Ca availability and supply were evaluated for their effect on marginal bract necrosis incidences of ‘Gutbier V-14 Glory’ poinsettia (Euphorbia pulcherrima Willd.). About 90% fewer marginal necrotic lesions were observed on plants receiving an 81% NO3-N and 903-ppm Ca soluble fertilizer with 10% of the total nutrients foliar-applied than on plants grown with medium-applied Osmocote 19N-2.6P-10K (47% NO3-N) or with medium-applied liquid fertilizer containing 30% or 65% NO3-N and 0 ppm Ca. Addition of 354 ppm Ca in a 53% NO3-N, or 964 ppm Ca in a 75% NO3-N medium-applied fertilizer did not significantly reduce the number of lesions compared to the same fertilizer with 0 ppm Ca or the equivalent rate of a 53% NO3-N Osmocote 14N-6.1P-11.6K. Weekly foliar-bract sprays of 432 ppm Ca from Ca(NO3)2·4H2O reduced numbers of lesions by 94% (

Plants of ‘Croft’, ‘Ace’ and ‘Nellie White’ grown in F- or Li-amended sand cultures had injured leaves. F-injury on ‘Croft’ developed as a semi-circular necrotic area at the margin of the leaf near its apex. The necrosis enlarged until the entire leaf tip and margin became necrotic. F injury on ‘Ace’ and ‘Nellie White’ varied from the semi-circular necrosis pattern to chlorotic or necrotic leaf margins. Injury affected only lower leaves of ‘Ace’ and ‘Nellie White’ but affected all leaves of ‘Croft’. Li injured leaves of all cultivars but the number and degree of injury were less than those produced by F. Li injury developed as chlorotic leaf margins which eventually became necrotic. In all cultivars Li injury was confined to lower leaves. ‘Croft’ was more sensitive to F and Li than ‘Ace’ or ‘Nellie White’. ‘Ace’ and ‘Nellie White’ were also grown in soil amended with dicalcium phosphate or superphosphate at both low and high lime rates and fertilized with NH4-N or NO3-N nitrogen. Plants grown with dicalcium phosphate with NH4-N or at any lime rate had no leaf injury. Plants grown with superphosphate had injured leaves, particularly at low lime rates with NH4-N. Soil and plant analysis showed a high positive correlation between superphosphate, which contains F, and leaf scorch. Soil-borne F was influenced by source of N fertilizer and lime rate. The pattern of leaf scorch from superphosphate in ‘Nellie White’ and ‘Ace’ was the same as that from NaF.

An apparent physiological disease, Yellow Strapleaf (YSL) of Chrysanthemnum morifolium Ram., was described by Jackson and Woltz (1) in 1959. The disease has been observed in Florida plantings during the last 6 years and has been noted in Massachusetts 3. Symptoms include chlorosis of new growth, green netting of leaves, and narrow strapshaped leaves that hook at the distal ends (fig 1A). The condition may persist for 2 to 8 weeks causing mild to severe stunting of plants and has been found in 20 commercial chrysanthemum varieties. YSL has not been corrected by the application of inorganic nutrient elements or linked directly with any fungal, bacterial, or viral pathogen. Chemical analyses of plant and soil have not indicated any significant differences in content of inorganic nutrients. Higher soil pH was usually associated with the disorder. Woltz and Jackson (6) presented results of experiments that linked frenching of tobacco (Nicotiana tabacum L.) and YSI, of chrysanthemum as being apparently caused by similar soil conditions and resulting in similar syndromes. Both disorders are favored by relatively high soil pH, periods of high soil moisture levels, and high soil temperatures. The symptoms displayed with the diseases (1, 5) have three common features: A: green netting or reticular chlorosis of leaves, B: narrow, strap-shaped leaves, and C: growth retardation. Tobacco and chrysanthemum plants growing together in containers of soil that had produced YSL in the field developed symptoms of the respective diseases of frenching and YSL. Following the information set forth by Steinberg (5) that isoleucine and certain other amino acids were effective in producing frenching, DL-isoleucine with DL-alloisoleucine was applied to the root zone of chrysanthemum plants. This amino acid treatment uniformly and quickly produced YSL symptoms with plants growing in solution culture, steamed soil, methyl bromide-treated soil, untreated soil, quartz sand and expanded volcanic glass (perlite). Six chrysanthemum varieties of varying degrees of susceptibility to YSL were treated with isoleucine in this experiment. YSL symptoms developed in all varieties with severity approximately in the order of observed field susceptibility. This report presents data on the effects of certain specific amino acids on the growth of chrysanthe

The question of the significance of free amino acids in soil or other cultural media has received attention in recent years in the fields of plant physiology (1, 3, 7, 13, 14, 15, 16, 17), soil microbiology (4, 5,11, 16) and soil chemistry (9, 10,12). Although it originally appeared that free amino acids were not to be found in soils, later reports (2, 10) indicated they could be extracted with aqueous and alcoholic solutions and determinations made with chromatographic methods. The quantities of amino acids found were quite variable. Amino acids added to soil were quite rapidly transformed, and usually undetectable in extracts made after 72 to 96 hours of incubation (11, 16). D-Amino acids and L-alloisoleucine appeared more resistant to change than other amino acids studied (16). Reports indicate that amino acids are absorbed by plants (3, 13, 14) and translocated with great speed in both phloem and xylem (8). Inhibitors of respiratory processes as well as low temperatures applied to fibrovascular tissue considerably retard translocation. The potential applications of research with the so-called unnatural (D-) isomers was pointed out (6, 17) in connection with the natural occurrences of Damino acids in antibiotics and parts of microorganisms. More recently, Ikawa, et al. (6) reported the finding of D-phenylalanine, D-allothreonine and D-alloisoleucine3 in peptido-lipids of bacterial origin. The demonstrated effectiveness of amino acids applied to root zones of plants in producing changes in morphology and growth rate (1, 13, 17) suggests a need for further research along these lines. Steinberg (13) found that frenching of tobacco could be simulated by furnishing leucine, isoleucine, or alloisoleucine to tobacco plants growing in sterile cultures. He reported that relatively large amounts of these amino acids were required under non-sterile conditions to produce frenching symptoms. Woltz and Jackson (15, 16, 17) found that symptoms of yellow strapleaf of chrysanthemum could be produced by small amounts of certain isomers of leucine, isoleucine, and alloisoleucine applied to the root zones of test plants growing in sterilized and nonsterilized media. Fifteen of twenty-two test plants developed syndromes similar to those of frenching and yellow strapleaf when a mixture of alloisoleucine and isoleucine isomers was applied to the root zones. Methionine applied to the root zones of chrysanthemum plants produced a physi-ological disorder given the name methionosis (17). Two of the twenty-two plants exhibited morphological changes due to methionine. A consideration of the information about the effects of externally applied amino acids on plant growth in the light of certain antimetabolite phenomena discussed by Woolley (18) led to the hypothesis that the growth-modifying effects observed might be largely antimetabolite effects. Natural (L-) amino acids could act as antimetabolites because of their structural similarity to other natural amino acids. Unnatural amino acids (D-form & others), due to their structural similarity to specific natural amino acids, could function as antimetabolites by being incorporated into peptides and blocking further synthesis due to the failure to completely fit the pattern of the natural amino acid. Experiments were planned to examine further the effects of various natural and synthetic amino acids on the growth rate and morphology of chrysanthemum plants. Chrysanthemum was selected for these studies because of its sensitivity to isomers of leucine, isoleucine, and methionine (17). The types of cultural media, amounts of amino acids applied, and timing of application relative to the development of new growth of axillary shoots were chosen to enhance growth effects so the effects might be recorded and evaluated. Interactions of related amino acids were explored to learn the degree to which the results would fit metabolite-antimetabolite relationships.

Thirty-nine cultivars of marigold (Tagetes spp.) were exposed to sulfur dioxide to determine their relative sensitivity. Flowering plants were fumigated at 1 ppm SO2 for 4 hours or at 2 ppm SO2 for 2 hours. The average foliar injury for all leaves on individual plants ranged from 42.3% for ‘Crackerjack Mix’ at 2 ppm SO2 to 0.0% for ‘Cupid Yellow’ at 1 ppm SO2. Foliar necrosis appeared as a gray to white marginal and/or interveinal scorch 1 day after exposure. There was a tendency for interveinal necrosis to be near the midvein. The extra-floral nectaries which line the leaf margins of marigold were scorched in 15 of the 39 cultivars. This injury may be of diagnostic value. Sepals were very sensitive to SO2. Sepal injury appeared as a pinpoint scorch and as tip burn, and was apparent in some cultivars when no foliar injury occurred.

Comparative fumigation procedures were used to evaluate the relative susceptibility of some ornamental plant species to the toxic effects of airborne fluoride in compartmentalized greenhouse chambers. Susceptibility classification was based on the speed of development of toxicity symptoms together with the specific concentrations of hydrofluoric acid vapor causing fluorosis. Symptoms of fluoride toxic effects were recorded for use in diagnosis and evaluation of damage.

Copper-sensitive and -resistant strains of Xanthomonas campestris pv. vesicatoria (XCV) were grown in specially purified nutrient solutions to study the interaction of Cu (0.0, 0.317, 1.0, 3.17, and 10 μg/ml) and Mg (0.25, 2.5, and 25 μg/ml) on the in vitro growth of XCV. The Cu-sensitive strain was inhibited considerably more than the resistant strain at 1.0, 3.17, and 10 μg/ml Cu levels. Bacterial growth of the Cu-sensitive strain at the highest Cu level was inhibited completely at all Mg levels. The Cu-resistant XCV, when exposed to the highest Cu concentration, was capable of significant growth at all Mg levels. An interaction between Cu and Mg was found with the resistant XCV at 3.17 and 10.0 μg/ml Cu whereby the Cu inhibition of growth of the XCV was much reduced by the high Mg level (25 μg/ml) in comparison with the intermediate Mg level (0.25 μg/ml). Mg, when applied as a foliar spray, may reduce the efficacy of copper sprays.

Fusarium wilt (Fusarium oxysporum Schlecht. f. sp. lycopersici (Sacc.) Snyder and Hansen) of tomato (Lycopersicon esculentum Mill.) was first reported in the United States in 1899 by E.F. Smith who said that the disease had put an end to the growing of tomatoes for the northern markets in certain areas of Florida. By 1920, the disease had become widespread and destructive throughout the southeast, midwest, and middle Atlantic states (Walker 1971).

The sensitivity of 26 cultivars of tomato (Lycopersicon esculentum Mill.) were compared at 2 concentrations of SO2 in specially designed exposure greenhouses. Cultivars studied included fresh market, processing, and specialty types. Insensitive and sensitive cultivars were identified by assessment of acute SO2-induced foliar necrosis. Cultivars found to be insensitive to SO2 included: ‘Ace’, ‘Bonanza’, ‘Heinz 1350’, ‘Tarquinia Tondino’, and ‘VF 145-B 7879’. Cultivars found to be sensitive to SO2 included: ‘Bellarina’, ‘Chico IIP, ‘Flora-Dade’, ‘Red Cherry Large’, ‘SubArctic Delight’, and ‘Vetomold’.

A hypothesis was tested that the cause of a damaging marginal bract necrosis common to ‘Gutbier V-14 Glory’ poinsettia is a deficiency of Ca that is expressed when the rapidly growing bract outdistances the current supply of Ca. Plants were grown in the greenhouse in a sedge peat-EauGallie sand mix with fertility adjustments designed to moderately enhance Ca deficiency. Twice-weekly foliar applications of Ca (432 ppm) were begun at the stage of first bract coloration to attempt to prevent necrosis. In addition to bract necrosis, puckering of bracts occurred on controls but not in Ca-treated plants. In another experiment, induced Ca deficiency symptomology included bract necrosis. Calcium chloride spray essentially prevented the necrosis. Necrotic bract marginal tissue had 0.07% Ca, whereas sprayed tissue contained more than three times this Ca concentration.

Atmospheric fluoride occasionally adversely affects foliage plants, especially intolerant species. The present report describes susceptibility to airborne fluoride damage of 34 foliage plants determined by comparative fumigation in compartmentalized greenhouses using 4 steady-state levels of hydrofluoric acid gas. Toxicity symptoms were recorded for diagnostic and damage evaluation purposes relative to air pollution effects.

Tomato leaves soaked in solutions of 7 antimetabolite compounds were offered to larvae of Spodoptera eridania (Cramer) to determine whether these materials affect larval feeding and development. Thiouracil-treated leaves were not appreciably consumed by larvae, weight gain was poor, and only 1 adult was produced from 54 larvae fed this diet. Thiouracil apparently acts as a deterrent to larval feeding.

Symptoms of fusarium wilt of tomato were less severe in plants supplied with nitrate-N and greater in those supplied with ammonium-N. Liming with calcium hydroxide decreased disease severity but this effect was negated by high ammonium-low nitrate fertilization. The combination of high nitrate, low ammonium, and lime reduced disease development additively. Fusarium oxysporum f. sp. lycopersici race 2 was more virulent when grown in liquid culture with ammonium than with nitrate as the sole N source.