bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Gamma Radiation on Soil and Diphenamid
Authors: Horowitz M. , Hulin Nira
Published: May 2019

Gamma radiation of 3 megarads (Mrad) achieved complete sterilization in Newe Ya'ar clay soil, without affecting subsequent growth of oats (Avena sativaL., var. Mulga) in the irradiated soil.N,N-dimethyl-2,2-diphenylacetamide (diphenamid) in aqueous solution or mixed within Newe Ya'ar soil was detoxified by irradiation with 3 Mrad.
Translocation of Terbacil in Purple Nutsedge
Authors: Ray B. R. , Wilcox Merrill , Wheeler W. B. , Thompson N. P.
Published: May 2019

Analysis of 3-tert-butyl-5-chloro-6-methyluracil (terbacil) in treated and untreated pairs of purple nutsedge (Cyperus rotundusL.), connected by rhizomes, indicated translocation of the herbicide. The tops and tubers of connected, untreated plants contained approximately 10% as much terbacil as did plants treated directly.
Selective Chemical Control of Cocklebur in Cottonseed
Authors: Smith James E. , Cole A. W.
Published: May 2019

Several chemicals were evaluated for their potential use in selectively killing cocklebur (Xanthium pensylvanicum Wallr.) seed in cocklebur-cottonseed (Gossypium hirsutum L.) mixtures. Reduction in cocklebur embryo viability from 64 to 100%, without injury to cottonseed, resulted from soaking seed in: (a) 20% ethyl or methyl acetate and 80% water for 3 to 15 min; (b) 35% methanol, 15% glacial acetic acid, and 50% water for 3 to 15 min; or (c) 50% methanol or ethanol, 20% glacial acetic acid, and 30% water for 15 to 30 sec. Evaluations of injury were based on tetrazolium tests, standard germination, germination in soil, and seedling dry weight.
Atrazine and Simazine Increase Yield and Quality of Range Forage
Authors: Kay Burgess L.
Published: May 2019

Application of 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine) to intermediate wheatgrass (Agropyron intermedium(Host) Beauv.) increased forage yields, plant protein, and nitrate over a 4-year period. Atrazine or 2-chloro-4,6-bis(ethylamino)-s-triazine (simazine) applied to a sward of red brome (Bromus rubensL.), Arabian grass (Schismus arabicusNees.), and red-stem filaree (Erodium cicutarium(L.) L'Her.) increased dry-matter yields sixfold and also increased protein and nitrate nitrogen. Nitrate in plants treated with atrazine increased to near-toxic levels for livestock.
Picloram Persistence in Semiarid Rangeland Soils and Water
Authors: Scifres C. J. , Hahn R. R. , Diaz-Colon J. , Merkle M. G.
Published: May 2019

Residues in soil, following application of 0.25 lb/A of 4-amino-3,5,6-trichloropicolinic acid (picloram) to semi-arid rangelands, usually were restricted to the top 12 inches for 60 days. Five ppb or less picloram were detected below 12 inches at 120 to 180 days after application; but picloram usually dissipated from the soil profile within a year. More picloram was detected 5 months after application at 6 to 18 inches deep at the lower ends of plots with 3% slopes than in plots with 0, 1, or 2% slopes. Runoff water from plots irrigated 10 days after treatment contained 17 ppb picloram. Irrigation or rainfall at 20, 30, or 45 days after picloram application resulted in less than 1 ppb picloram in runoff water. No more than 1 or 2 ppb picloram were detected after dilution of runoff water in large ponds.
Anatomy of Johnsongrass
Authors: McWhorter C. G.
Published: May 2019

The number of vascular bundles in the rhizomes of different ecotypes of johnsongrass (Sorghum halepense(L.) Pers.) varied from 71 to 154. The size of vascular bundles varied from 60 to 150 μ in an ecotype from California to 100 to 230 μ in an ecotype from Georgia. The size of xylem cells in these vascular bundles also varied widely, but the size of phloem cells was more constant. The number of vascular bundles in culms ranged from 43 to 123. The average number of vascular bundles in individual leaves varied from 46 to 158 for different ecotypes. The number of stomata on leaf surfaces deviated from 63 to 148/sq mm for 10 different ecotypes. An average of 95 stomata/sq mm occurred on the upper surface of johnsongrass leaves while an average of 113 stomata occurred on lower surfaces. The arrangement and size of stomata varied in different johnsongrass ecotypes.
Control of Waterlilies with Dichlobenil
Authors: Comes R. D. , Morrow L. A.
Published: May 2019

Early postemergence applications of 2,6-dichlorobenzonitrile (dichlobenil) granules at 15 lb/A controlled 97 to 99% of dwarf waterlily (Nymphaea tetragonaGeorgi) in a shallow lake for 3 years. Dichlobenil alone was superior to a combination of dichlobenil and (2,4-dichlorophenoxy)acetic acid (2,4-D) for the control of dwarf waterlily and western yellow waterlily (Nuphar polysepalumEngelm). Reinfestation was more rapid on plots 25 by 25 ft in size than on plots 50 by 50 ft in size. When a high degree of control was maintained for 2 or 3 years, rhizomes of dwarf waterlily and a 1 to 2-ft layer of hydrosoil floated to the lake surface 17 months after dichlobenil was applied.
Adsorption of Picloram by Soil Colloids and Various Other Adsorbents
Authors: Grover R.
Published: May 2019

The adsorption of picloram (4-amino-3,5,6-trichloropicolinic acid) was studied for several Canadian prairie soils and for various other adsorbents. The kd values for the soils ranged from 0.09 to 0.75 and were correlated only with soil organic matter. The kd values for other adsorbents varied from 0 to 232, the order of adsorption being activated charcoal > anion exchange resin > peat moss > cellulose triacetate. There was no adsorption of picloram on montmorillonite and kaolinite clays, cation exchange resin, wheat straw (Triticum aestivumL.), or cellulose powder. The differences in the adsorption of picloram were explained on the basis of the relative affinities of the various adsorptive surfaces for the molecular or the ionized forms of the acid.
Growth of Johnsongrass Selections Under Different Temperatures and Dark Periods
Authors: Burt G. W. , Wedderspoon I. M.
Published: May 2019

The differential response of three selections of johnsongrass (Sorghum halepense(L.) Pers.) to different temperatures and dark periods was studied in two experiments conducted in growth chambers. The three selections of johnsongrass were obtained from locations representing different climates. At 20 C all three selections grew equally with respect to most parameters of growth studied; however, at 35 C the selection from the southern climate produced more total fresh weight than the other two selections. Rhizome production and the number of stems also were greater in the southern selection at 35 C. An 8-hr dark period prevented flowering in all three selections and significantly reduced rhizome production in two selections compared to the 12-hr dark period. Flowering occurred most rapidly in the selection from a northern climate and most slowly in the selection from a southern climate. The results are discussed in relation to the possible plant adaptive changes and the possibility of weed control through dark period interruption.
Introduction and Spread of Johnsongrass in the United States
Authors: McWhorter C. G.
Published: May 2019

An extensive search of the literature and records was conducted to determine when and how johnsongrass (Sorghum halepense(L.) Pers.) was introduced into the United States. Previous authors surmised that johnsongrass was imported from the Mediterranean area, but my search revealed that no agriculturist from the United States had worked in the Mediterranean region before 1840. Although Dr. James B. Davis assisted the Turkish Empire in cotton culture in the 1840's, there is evidence that johnsongrass was grown throughout the Southeast by 1830 if not before. Documentation of the initial introduction and distribution was hampered by the use of more than 40 common names for this weed in the nineteenth century. At least eight different Latin names were used to identify johnsongrass in the 1800's. The use of johnsongrass as a common name on a national basis resulted from a letter written by Herbert Post of Selma, Alabama, in 1874 to George Vasey, an employee of the U. S. Department of Agriculture in Washington. In 1880, John Haralson of Selma, Alabama, wrote to D. L. Phares of Woodville, Mississippi, that johnsongrass was the common name used in his area. These letters were published in the Monthly Report of the U. S. Department of Agriculture and in Farmers Book of Grasses, respectively; the wide attention that these received resulted in the common name of johnsongrass. The name was derived from that of William Johnson, a farmer of Marion Junction, Alabama, who presumably introduced it into Alabama. By the late nineteenth century, the presence of johnsongrass was almost nationwide. Many reports testify to the severity of the problem caused by this weed in the late 1800's. Its pernicious nature led to the first Federal appropriation specifically for weed control in 1900, and to the first report on johnsongrass control, prepared by C. R. Ball in 1902.
Influence of Environment on Metabolism of Propanil in Rice
Authors: Hodgson Richard H.
Published: May 2019

The metabolism of 3′,4′-dichloropropionanilide (propanil) to 3,4-dichloroaniline (hereinafter referred to as 3,4-DCA) andN-(3,4-dichlorophenyl)glucosylamine (hereinafter referred to as 3,4-DCAG) was quantitatively modified in rice (Oryza sativaL. ‘Nato’) by temperature and day length. The propanil, 3,4-DCA, and 3,4-DCAG content of rice was determined 1, 2, 5, and 8 days after root treatment with 92 μM propanil. Plants were grown and treated under long-day (16 hr) and short-day (12 hr) conditions with day temperatures of 32, 27, or 21 C and night temperatures of 21 C. Absorption and metabolism of propanil were most rapid under high temperature and long day conditions. A mean value of 0.75 μmoles total of aniline equivalent per plant was obtained. Greater quantities of 3,4-DCA and 3,4-DCAG were recovered from plants in high temperature, long day environments. An average of 47% of the propanil plus water-soluble metabolites in rice was in root tissue. Conditions favoring high growth rates and transpiration increased the percentage in the shoots. Because of the increased tissue mass at high temperatures, mean concentrations of propanil plus water-soluble metabolites in plant tissue were reduced from 0.18 to 0.12 μmoles/g dry weight.
Hydroxylation of 2,4-D in Several Weed Species
Authors: Fleeker J. , Steen R.
Published: May 2019

Wild buckwheat (Polygonum convolvulus L.), leafy spurge (Euphorbia esula L.), yellow foxtail [Setaria glauca (L.) Beauv.], and wild oat (Avena fatua L.) hydroxylated, in a 7-day period, 2 to 7% of the (2,4-dichlorophenoxy)acetic acid-1-14C (2,4-D-1-14C) absorbed. Only a trace of hydroxylation products was detected in wild mustard [Brassica kaber (DC.) L. C. Wheeler var. pinnatifida (Stokes) L. C. Wheeler], perennial sowthistle (Sonchus arvensis L.), and kochia [Kochia scoparia (L.) Roth]. The investigation was limited to hydroxylation on the para-position of the herbicide. The predominant product, 2,5-dichloro-4-hydroxyphenoxyacetic acid, was detected in all weed species studied. Also found in measurable amounts in some species were 2,3-dichloro-4-hydroxyphenoxyacetic acid and 2-chloro-4-hydroxyphenoxyacetic acid. The hydroxylation rate on the number four carbon of the ring did not account for the variation in susceptibility exhibited by these plants.
Species Susceptibilities to 2,4-D on Mixed-Grass Prairie
Authors: Hyder D. N.
Published: May 2019

Thirteen prominent species decreased 40% or more after applications of (2,4-dichlorophenoxy)acetic acid (2,4-D) at 2.2 kg/ha. Four of the “most-susceptible” species [gumweed (Grindelia squarrosa (Pursh) Dunal), fringed sagebrush (Artemisia frigida Willd.), drummond milk vetch (Astragalus drummondii Dougl. in Hook.), and hairy goldaster (Chrysopsis villosa (Pursh) Nutt.)] are considered undesirable and two of them [bluebells (Mertensia lanceolata (Pursh) A. DC.) and evening-primrose (Oenothera coronopifolia Torr. & Gray)] desirable. The other seven species of this group are quite unimportant for cattle. Therefore, spraying mixed-grass prairie with 2,4-D improves range condition and increases forage production.
Night Applications of Phenoxy Herbicides on Plains Pricklypear
Authors: Schuster Joseph L.
Published: May 2019

Night applications of phenoxy herbicides on plains pricklypear (Opuntia polyacantha Haw.) resulted in more plants being killed than comparable day applications. Night applications gave rapid herbicidal responses that were negated by the second year if chemical concentrations were too high. With low herbicide concentrations (½ and 1 lb aehg) effectiveness increased with proportion of diesel oil in carrier. The ester forms of 2-(2,4,5-trichlorophenoxy)propionic acid (silvex) killed more plants than did the ester or amine forms of (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T) in diesel oil:water (1:4, v/v) carriers.
Herbicidal Inhibition of Ga-Induced Synthesis of α-Amylase
Authors: Jones D. W. , Foy C. L.
Published: May 2019

The activity of α-amylase in barley (Hordeum vulgareL. ‘Wong’) half-seeds, induced by exogenous gibberellic acid (GA), was almost completely inhibited by 5 × 10−4M commercial formulations of (2,3,6-trichlorophenyl)acetic acid (fenac), 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil), and 7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylic acid (endothall). At the same concentration, 1,1′-dimethyl-4,4′-bipyridinium ion (paraquat) caused severe inhibition (72%); 2,2-dichloropropionic acid (dalapon) was intermediate (42%); and α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin), 2-(4-chloro-6-ethylamino-s-triazin-2-ylamino)-2-methylpropionitrile (SD 15418), and 2% solvent dimethylsulfoxide (DMSO) were only slightly inhibitory to GA-induced α-amylase production.
Response of Sugarbeets and Weeds to Phenmedipham and Two Analogues
Authors: Schweizer E. E. , Weatherspoon D. M.
Published: May 2019

Responses of weeds and sugarbeets (Beta vulgarisL.) to postemergence treatments of methylm-hydroxycarbanilatem-methylcarbanilate (phenmedipham) and two analogues were evaluated in six field studies. Phenmedipham at 1.7 kg/ha controlled foxtail millet (Setaria italica(L.) Beauv.) and kochia (Kochia scoparia(L.) Schrad.) better than 2.2 kg/ha of methylm-hydroxycarbanilate carbanilate and ethylm-hydroxycarbanilate carbanilate. Pigweed (Amaranthusspp.) was controlled better by the analogues at 1.1 kg/ha than by phenmedipham. The foliar growth of sugarbeets was generally suppressed more by the analogues than by phenmedipham, but injury was not considered detrimental at 1.1 kg/ha. Yield of sugarbeet roots and sugar was reduced by 7% or less by phenmedipham at rates of 1.1 to 4.5 kg/ha, but these yield reductions were associated primarily with the failure of phenmedipham to completely control all weeds for 5 to 9 weeks after treatment.
Reactions of Several Crops to Dichlobenil
Authors: Hardcastle W. S. , Wilkinson R. E.
Published: May 2019

Tolerance of corn (Zea maysL. ‘B’), cotton (Gossypium hirsutumL. ‘coker 413’), soybean (Glycine maxMerr. ‘Hardee’), turnip (Brassica rapaL. ‘Tendergreen’), sorghum (Sorghum bicolor(L.) Moench. ‘Georgia 615’), purple nutsedge (Cyperus rotundusL.), yellow nutsedge (C. esculentusL.), and johnsongrass (Sorghum halepense(L.) Pers.) to 2,6-dichlorobenzonitrile (dichlobenil) at 0, 0.14, 0.28, 0.56, 1.12, and 2.24 kg/ha in four Georgia soils was determined. Equivalent rates of dichlobenil generally were more toxic in Davidson clay loam which had the highest clay content. Crop tolerance was corn > sorghum > cotton > turnip. Purple and yellow nutsedge tolerance to dichlobenil was intermediate to that of the crops tested. Johnsongrass response was equivalent to that shown by sorghum.
Influence of Time of Herbicide Application on Control of Kudzu
Authors: Dickens Ray , Buchanan G. A.
Published: May 2019

Field experiments were conducted during 1968 to 1970 to determine the influence of time of herbicide application on control of kudzu [Pueraria lobata (Willd.) Ohwi]. Picloram (4-amino-3,5,6-trichloropicolinic acid) effectively controlled kudzu when applications were made as early as May 22 and as late as October 28. Acceptable control was obtained with rates of picloram 0.34 kg/ha or higher. In contrast, (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T) was most effective when applied during the first half of summer. Essentially no control of kudzu was obtained from 2,4,5-T applied 1 week before the first killing frost.
A Versatile Tractor-Mounted Research Spray System
Authors: Whiting Fred L. , Lyons James M.
Published: May 2019

A simple, inexpensive, and versatile tractor-mounted spray system will allow spray application to be made to approximately six 6.1-m plots per minute under continuous operation.
Vitality of Tubers of Yellow Nutsedge Treated by Arsenical Herbicides
Authors: Keeley P. E. , Thullen R. J.
Published: May 2019

We collected tubers from greenhouse-grown yellow nutsedge (Cyperus esculentusL.) control plants and plants foliarly-treated with 3.36 kg/ha of disodium methanearsonate (DSMA) or monosodium methanearsonate (MSMA). Where sufficient tubers were produced, they were separated into two classes, large and small. Some of the tubers were analyzed for elemental arsenic, and others were stored at 2 C and planted at various intervals. Vitality of tubers was noted in terms of sprouting and vegetative growth. Tubers collected from treated plants contained significantly more arsenic (4 to 33 ppm) than control tubers (1 ppm). Tubers collected from treated plants and planted without separation sprouted in significantly reduced numbers compared to control tubers. Small tubers contained a significantly higher concentration of arsenic (23 to 33 ppm) than large tubers (4 to 12 ppm). The treatments reduced the vitality of small tubers but had little or no effect on vitality of large tubers.
Morphological and Anatomical Effects of Pyrazon on Bean
Authors: Rodebush J. E. , Anderson J. L.
Published: May 2019

Bean (Phaseolus vulgarisL., var. Tendercrop) plants treated during germination with 100 ppm 5-amino-4-chloro-2-phenyl-3(2H)-pyridazinone (pyrazon) were indistinguishable from untreated plants until 5 days after seedling emergence. Chlorosis began at the leaf margins, progressed inward, and became more severe until the leaves became necrotic and died. Similar symptoms were observed on leaves of plants treated with 25 and 50 ppm, but they appeared 4 to 10 days later. The light-microscope study of leaf tissue revealed that chloroplast form and arrangement were altered by pyrazon treatment. Chloroplasts in leaves of treated plants became round and swollen rather than discoid, contained no starch, aggregated in clumps, and developed an affinity for safranin stain.
Comparison of Salt and Ester Formulations of Picloram
Authors: Bovey R. W. , Ketchersid M. L. , Merkle M. G.
Published: May 2019

Under Texas conditions, the potassium salt of 4-amino-3,5,6-trichloropicolinic acid (picloram) usually was more effective than the isooctyl ester formulation for control of live oak (Quercus virginianaMill.), yaupon(Ilex vomitoriaAit.), winged elm(Ulmus alataMichx.), huisache (Acacia farnesiana(L.) Willd.), and honey mesquite(Prosopis juliflora(Swartz) DC. var.glandulosa(Torr.) Cockerell). Possible reasons for the difference in effectiveness of picloram formulations were studied in the laboratory. Extensive degradation of the ester of picloram (96%) occurred in open Petri dishes after 72 hr exposure to ultraviolet (uv) light, compared to a loss of 26% for the salt of picloram. Forty-five percent of the isooctyl ester of picloram was lost at high temperatures (60 C), whereas only 2% of the potassium salt of picloram was lost after 1 week at 60 C from open Petri dishes in a dark oven. Application of the ester to soils reduced thermal and ultraviolet light degradation losses compared to losses from open Petri dishes. Loss of the ester was greater when applied in diesel oil to Petri dishes than in either water or paraffin oil. The salt of picloram leached most after 12.5 cm simulated rainfall in soil columns to the 17.5 to 30-cm level (907 μg), followed by the acid (360 μg), and last the isooctyl ester (0 μg). However, considerable acid (161 μg) was recovered at the 32.5 to 45-cm depth from the isooctyl ester treatment exposed to wet soils for 3 days, indicating hydrolysis of the ester to acid.
Effects of Pyrazon on Bean Chloroplast Ultrastructure
Authors: Anderson J. LaMar , Schaelling J. Philip
Published: May 2019

The fine structure of the chloroplasts of bean(Phaseolus vulgarisL., var. Tendercrop) was grossly altered by treatment with 5-amino-4-chloro-2-phenyl-3(2H)-pyridazinone (pyrazon) when plants were grown in a treated medium. Alterations occurred first at the leaf margins and preceded visual symptoms. Chloroplasts became spherical and swollen rather than discoid, clumped rather than peripherally arranged, and were totally devoid of starch. Grana formation was inhibited; the thylakoids became swollen and perforated, and they ultimately disintegrated. Concomitant with grana inhibition was the increase in size and number of lipid globules. Occasional breakage of the outer chloroplast membrane was observed. It is proposed that these changes result because pyrazon inhibits thylakoid structural protein formation.
Velvetleaf Control as Influenced by Herbicide Placement and Seed Depth
Authors: Herr Donald E. , Stroube Edward W.
Published: May 2019

In a 3-year field study, from 51 to 1% of seed of velvetleaf(Abutilon theophrastiMedic) planted at 1 and 6-inch depths, respectively, produced established plants. Utilizing a microplot technique, 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine) and the ammonium salt of 3-amino-2,5-dichlorobenzoic acid (amiben) were applied at 2 and 3 lb/A, respectively, at soil depths of 0, 2, and 4 inches. Velvetleaf seed were planted at depths of 1, 2, and 3 inches. Compared with the number of plants establishing in untreated plots, surface-applied amiben reduced the number of established plants 39, 23, and 29% from seed planted at depths of 1, 2, and 3 inches, respectively. Amiben at or below seed depth gave over 95% control, and when applied below the soil surface but above the seed, 86% control. Atrazine, surface-applied, reduced weed establishment 33, 62, and 85% from seed planted at depths of 1, 2, and 3 inches, respectively. When atrazine was at, below, or above the seed but below the soil surface, control was 96% or higher.
An Injector-Planter for Subsurface Placement of Herbicides
Authors: Dowler Clyde C. , Hauser E. W.
Published: May 2019

We constructed an injector-planter which simultaneously plants seed and injects herbicides. It effectively placed volatile herbicides under the soil surface in precise spatial relationship to crop seed. Rolling coulters, placed in front of the herbicide delivery system, enabled the unit to cut through trash better than previously-described equipment and, therefore, perform effectively under a wider range of soil conditions.
Chemical Control of Western False Hellebore
Authors: Williams M. Coburn , Kreps L. B.
Published: May 2019

Several herbicides were evaluated for control of western false hellebore (Veratrum californicumDurand). The dimethylamine salt and propylene glycol butyl ether esters of (2,4-dichlorophenoxy)acetic acid (2,4-D), potassium salt of 2-[(4-chloro-o-tolyl)oxy]propionic acid (mecoprop), and the butoxy ethanol ester of 2-(2,4,5-trichlorophenoxy)propionic acid (silvex) controlled 95 to 99% of the plants when applied at 2 lb/A followed by 2 lb/A of the dimethylamine salt of 2,4-D the second year. Optimum control was achieved when plants were treated after the last leaf had expanded and before flower bud initiation.
Tractor-Mounted Sprayers for Applying Herbicides to Brush
Authors: Flynt T. O. , Bovey R. W. , Baur J. R. , Meyer R. E.
Published: May 2019

We developed two tractor-mounted spraying systems which utilize compressed air for dispensing the spray. The nursery sprayer consists of a spraying platform, two windshields, and two hand booms, and was developed to spray brush up to 6 ft tall. A field sprayer was developed to spray brush up to 15 ft tall. This sprayer has two 20-ft booms, mounted on a modified front end loader which could be rotated hydraulically to either side of the tractor.
Herbicidal Activity as Affected by Soil Incorporation and Rainfall
Authors: Wiese A. F. , Smith D. T.
Published: May 2019

Under the erractic rainfall distribution of the Southern Great Plains, average pigweed(Amaranthussp.) control in five studies with seven herbicides was enhanced by incorporation in 1 or 3 inches of soil with a power rototiller. Compared to no incorporation, 9-inch incorporation improved pigweed control with two herbicides, had no effect on weed control with two others, and decreased weed control with another three. Soil incorporation at 1 or 3 inches did not increase weed control with three compounds if 0.4 inch of rainfall occurred within 2 weeks after application. Incorporation into 1 or 3 inches of soil improved weed control with four herbicides even when rainfall occurred within 2 days after application. In four of the trials, neither herbicides nor incorporation depth affected cotton stand or vigor. Under the soil moisture conditions prevailing in the one trial where yield data were obtained, cotton(Gossypium hirsutumL.) stand and lint yield decreased lineally with depth of soil incorporation. Herbicides did not affect cotton stand or yield.
Effect of Herbicides on Weed Control and Growth of Pecan Trees
Authors: Norton Jack A. , Storey J. Benton
Published: May 2019

Simazine (2-chloro-4,6-bis(ethylamino)-s-triazine), 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron), anda,a,a-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) were evaluated for weed control in pecan(Carya illinoensis(Wang.) K. Koch) orchard establishment. Maximum weed control and tree growth occurred in plots treated with diuron and simazine applied at 3.0 and 4.0 lb/A, respectively. During the second year, phytotoxic symptoms were observed in plots which had received superimposed annual treatments of diuron at 3.0 lb/A, but none appeared in simazine or trifluralin plots.
DI QUESTA RIVISTA
Authors: G. S.
Published: May 2019

Introduzione

In Italia le riviste che si occupano di politica non mancano, anzi abbondano. Ma manca, o mancava, una rivista di scienza politica, vale a dire espressamente e specificamente destinata allo studio della politica sub specie scientiae. Mancanza di cui si ha la riprova nelle riserve e nei malintesi che tuttora avvolgono questo settore di studi.
MODELLI SPAZIALI E L'IDENTIFICAZIONE PARTITICA DELL'ELETTORE ITALIANO
Authors: Barnes Samuel H.
Published: May 2019

Introduzione

Il miglior risultato che si possa ottenere dalla ricerca empirica è costituito da un eccellente accordo tra la teoria ed i dati: il fatto che questo stato di cose si verifichi di rado non fa che renderlo ancora piú piacevole. Le scienze sociali riescono infatti meglio nel criticare che non nel fornire prove, nel dimostrare l'inesattezza di ciò che crediamo di sapere piuttosto che nel costruire utili modelli di comportamento. Ancora meno di frequente avviene che si riesca a provare fondate sul piano della realtà empirica nozioni date per scontate nell'uso corrente. È ovvio infine che una delle meno frequenti evenienze è quella di trovare che la teoria ed i dati contribuiscono a provare come il folklore politico sia esatto. Eppure è proprio uno di questi esoterici risultati che il presente saggio ha il piacevole compito di esporre.
GOVERNI E SISTEMI DI PARTITO IN DIECI PICCOLE DEMOCRAZIE EUROPEE
Authors: Daalder Hans
Published: May 2019

Introduzione

L'argomento di questo articolo é stato affrontato in scienza politica sotto tre angolazioni principali: 1) quella della letteratura tradizionale di politica comparata, che si é concentrata principalmente sulle variabili istituzionali, 2) quella dello studio cornparato dei sistemi di partito, e 3) quella della teo ria delle coalizioni.
POLITICA E PREVISIONE TECNOLOGICA: UN CODICILLO A DANIEL BELL
Authors: Sartori Giovanni
Published: May 2019

Introduzione

Senza un criterio di decifrazione, senza una chiave esplicativa, tanto il passato come il futuro sono soltanto zone di buio. La ricerca di questo «decifratore» appartiene, tradizionalmente, a quel capitolo della Iilosofia che viene detto «filosofla della storia ». Ma per quanto si dica cosí, è chiaro che una volta fatta la scelta del criterio esplicativo questo criterio deve valere indiflerentemente tanto per il passato come per il futuro, tanto per la retrospezione come per la previsione, tanto all'indietro come in avanti. In pratica, tuttavia, chi cerca di decifrare il futuro si trova meglio con talune chiavi esplicative che non con altre. Non è affatto una coincidenza che il futurologo opti, il più delle volte, per un tipo di spiegazione tecnologica e tecnostrutturale.
The Legion and the Centuriate Organization
Authors: Sumner G. V.
Published: May 2019

It is generally recognized that Rome of the early Republic offers a good example of the correlation between military and political organization. The ordering of the Roman citizenry in centuries, classes and age-groups was in origin and essence a military system. The Comitia Centuriata was the exercitus urbanus—the army on parade in the Field of Mars.

But by the third century B.C. the Roman army and the centuriate assembly were manifestly two different systems, even if vestiges of their interconnection lingered on. The process whereby this differentiation had come about is, unfortunately, not so clear. The traditional accounts of early Roman history generally failed to devote much attention to questions of that order. Yet the effort to tackle and, if possible, solve this complex of problems can hardly be evaded. The answers given, or assumed, by modern historians are bound to determine how the whole history of early Rome is interpreted and represented.
The Development of the Praetor's Edict
Authors: Watson Alan
Published: May 2019

So much has been written on even the most minute problems of Roman Law that it is surprising to find topics of fundamental importance which have been generally neglected. But such a one is the course of development of the praetorian Edict—perhaps the most important source of Roman law—despite the broad studies of Dernburg and Kelly.

Two primary difficulties face any attempt to reconstruct the course of development of the Edict. The first is the extreme rarity of positive or virtually positive dates for the introduction of individual edicts. In fact there are only four. The edictum de hominibus armatis coactisve et vi bonorum raptorum was introduced by M. Lucullus who was praetor peregrinus—not praetor urbanus—in 76 B.C. The edictum de dolo was the work of Aquilius Gallus who was a praetor in 66 B.C. An edict on metus was issued almost certainly by the Octavius who was consul in 75 B.C. and hence praetor not later than 78. It is noteworthy that all positive dating for these three edicts comes from Cicero.
The Extortion Law of the Tabula Bembina
Authors: Mattingly Harold B.
Published: May 2019

In a previous article, based on a rigorous study of the text on both sides, I hope to have shown that fragments A and B of the famous Tabula Bembina should be set c. 35 letter-spaces closer together than in Mommsen's edition, and that the estimated width of the tablet should be reduced correspondingly. This is likely to have disturbing consequences. In particular, it now seems fairly certain that four whole chapters of the extortion law—mainly concerning rewards to prosecutors—recur verbatim in the fragmentary republican law from Tarentum. I would like to probe this matter further. Theoretically three possibilities would appear to be open. The two laws could be identical. The passage could have been transferred from one extortion law to another. Or, thirdly, it could have been adapted from the extortion law to a statute governing another quaestio. Schönbauer indeed argued that the Tarentine law was the Lex Apuleia de maiestate. Against this one must set the strong arguments for identifying the Lex Bantina with Saturninus' treason law. Though there is some overlap, the Lex Tarentina and the Lex Bantina are clearly not parts of the same measure.
Roman Gold-Mining in North-West Spain
Authors: Lewis P. R. , Jones G. D. B.
Published: May 2019

The Augustan conquest of the Asturias was resisted with all the tenacity native to that region, but under the combined pressure of no less than three legions, this wild and mountainous area of North-Western Spain finally capitulated in c. 25 B.C. On the Roman side the prospect of mineral exploitation was a major motive that demanded at times the presence of both Augustus and Agrippa. The literary references to the Spanish mining-projects that followed the conquest do not specify particular sites, but indicate instead general areas where mining was initiated. Fortunately, however, the gold-rushes of the last century in California and elsewhere reawakened interest in other areas of the world, and particularly this region of Spain, partly as a result of the legendary stories of Roman successes. The prospectors found many traces of those efforts, although in the main unsuccessful themselves. Part at least of what they saw was recorded in the current mining papers and journals of that period, and we are indebted to the work of O. Davies for abstracting and summarizing much of this information, which would otherwise be difficult to assimilate, the sources now being unobtainable or very inaccessible. We may be sure that the twenty or so mines that he noted are an underestimate, and that many more await discovery. Although Davies' list was made over thirty years ago, none of the sites have since been surveyed in any detail and no photographic record exists.
Analysis of Speed Prediction Error on Oceanic Flights
Authors: Mori Ryota
Published: May 2019

The accuracy of speed prediction error to the next waypoint is a key factor in maintaining longitudinal separation on oceanic routes. This estimation is often used by air traffic control to estimate the future position of aircraft, and the estimation errors result in potential separation infringement. While most aircraft can calculate the estimated time at each future waypoint using the onboard Flight Management System, the factors affecting the inaccuracy of the estimation require more clarification. This paper investigates the accuracy of the speed prediction error on oceanic routes and examines the main factor of error using airline flight data. The results show that wind prediction error is a main source of speed prediction error, and significant differences of the speed prediction error among airlines and aircraft types were observed.
Forecasting health expenses using a functional data model
Authors: Piontkowski Jens
Published: May 2019

Traditionally, actuaries make their predictions based on simple, robust methods. Stochastic models become increasingly popular because they can enrich the point estimates with error estimates or even provide the whole probability distribution. Here, we construct such a model for German inpatient health expenses per age using the functional data approach. This allows us to see in which age groups the expenses change the most and where predictions are most uncertain. Jumps in the derived model parameters indicate that 3 years might be outliers. In fact, they can be explained by changes in the reimbursement system and must be dealt with. As an application, we compute the probability distribution of the total health expenses in the upcoming years.
Belief in a Just World and Emotional Intelligence in Subjective Well-Being of Cancer Patients
Authors: Megías Jesús L. , Romero Yolanda , Ojeda Begoña , Peña-Jurado Inmaculada , Gutiérrez-Pastor Pilar
Published: May 2019

The study of coping strategies has provided valuable insights about the process of helping cancer patients adapt to their disease. However, new approaches must be explored to increase the knowledge of this adjustment. In this study, we will analyze the relationship between patients’ psychological well-being and quality of life and less well-studied constructs such as the belief in a just world (BJW) and emotional intelligence (EI). Sixty-eight cancer patients (35 men, 33 women; mean age 53.5 years; range: 20–86) were asked about their personal and general BJW, EI, Perception of Quality of Life, Anxiety, and Depression. Different multiple regression analyses showed that patients’ personal BJW negatively predicted their anxiety (p< .05) and a trend to a better quality of life. In addition, patients with high scores in the Mood Repair subfactor of EI showed better quality of life (p< .05), and those with higher Attention to Feelings exhibited more Anxiety (p< .01) and a trend to more Depression. These results underline the need to take into consideration new factors, such as BJW and EI, in clinical interventions for cancer patients.
Gauging in the Rain
Authors: den Hond Bas
Published: May 2019

Measuring how much water falls from the sky is more complicated than it seems. To improve measurements, researchers are looking at umbrellas, hydrophones, and gamma ray detectors.
Thermal Structure of the Forearc in Subduction Zones: A Comparison of Methodologies
Authors: van Keken Peter E. , Wada Ikuko , Sime Nathan , Abers Geoffrey A.
Published: May 2019

Molnar and England (1990, https://doi.org/10.1029/JB095iB04p04833) introduced equations using a semianalytical approach that approximate the thermal structure of the forearc regions in subduction zones. A detailed new comparison with high‐resolution finite element models shows that the original equations provide robust predictions and can be improved by a few modifications that follow from the theoretical derivation. The updated approximate equations are shown to be quite accurate for a straight‐dipping slab that is warmed by heat flowing from its base and by shear heating at its top. The approximation of radiogenic heating in the crust of the overriding plate is less accurate but the overall effect of this heating mode is small. It is shown that the previous and updated approximate equations become increasingly inaccurate with decreasing thermal parameter and increasing variability of slab dip. It is also shown that the approximate equations cannot be extrapolated accurately past the brittle‐ductile transition. Conclusions in a recent paper (Kohn et al., 2018, https://doi.org/10.1073/pnas.1809962115) that modest amount of shear heating can explain the thermal conditions of past subduction from the exhumed metamorphic rock record are invalid due to a number of compounding errors in the application of the Molnar and England (1990, https://doi.org/10.1029/JB095iB04p04833) equations past the brittle‐ductile transition. The use of the improved approximate equations is highly recommended provided their limitations are taken into account. For subduction zones with variable dip and/or low thermal parameter finite element modeling is recommended.
Oxygen Isotopes (δ18O) Trace Photochemical Hydrocarbon Oxidation at the Sea Surface
Authors: Ward Collin P. , Sharpless Charles M. , Valentine David L. , Aeppli Christoph , Sutherland Kevin M. , Wankel Scott D. , Reddy Christopher M.
Published: May 2019

Although photochemical oxidation is an environmental process that drives organic carbon (OC) cycling, its quantitative detection remains analytically challenging. Here, we use samples from the Deepwater Horizon oil spill to test the hypothesis that the stable oxygen isotope composition of oil (δ18OOil) is a sensitive marker for photochemical oxidation. In less than one‐week, δ18OOil increased from −0.6 to 7.2‰, a shift representing ~25% of the δ18OOC dynamic range observed in nature. By accounting for different oxygen sources (H2O or O2) and kinetic isotopic fractionation of photochemically incorporated O2, which was −9‰ for a wide range of OC sources, a mass balance was established for the surface oil's elemental oxygen content and δ18O. This δ18O‐based approach provides novel insights into the sources and pathways of hydrocarbon photo‐oxidation, thereby improving our understanding of the fate and transport of petroleum hydrocarbons in sunlit waters, and our capacity to respond effectively to future spills.
Theoretical Prediction of Asymmetric Instability of Drift Kinetic Alfven Waves in Anisotropic Plasmas
Authors: Bashir M. F. , Chen Lunjin , Ilie Raluca
Published: May 2019

The asymmetric instability of drift kinetic Alfvén waves (DKAWs) is analyzed to study the interplay between the density inhomogeneity and the temperature anisotropy, including the wave‐particle interaction and finite ion Larmor radius effects. The asymmetric behavior arises due to the opposite diamagnetic drifts of electrons and ions and quantifies the contribution of electron drift waves and ion drift waves in altering the dispersion characteristic of DKAWs. It is shown that the coupling of drift waves with kinetic Alfvén waves leads to the generation of three different frequency (i.e., higher, intermediate, and lower) modes of DKAWs. The comparison of their propagation characteristics and stability mechanisms applicable to a wide range of plasma parameters is provided. The analytical dispersion relation can be used as an improved theoretical tool for identifying the existence of DKAWs and their source region in the multisatellite observations, especially near the reconnection X‐line.
Mycobacterium abscessus-associated vertebral osteomyelitis in an immunocompetent patient: a rare case report and literature review
Authors: Moral Muhammad Z. , Desai Khusboo , Arain Abdul R. , O’Leary Robert E. , Haddad Stefanos F. , Lawrence James P.
Published: May 2019

Introduction

Vertebral osteomyelitis (VO) is an uncommon infection with Staphylococcus aureus as the most commonly implicated organism. VO caused by nontuberculous mycobacteria (NTM) such as Mycobacteriumabscessus (M. abscesscus) is exceedingly rare with only eight cases reported in literature.

Case presentation

We report a rare case of an 82-year-old male with a remote history of trauma who was diagnosed with NTM vertebral osteomyelitis. The patient initially underwent a vertebroplasty of T12 and kyphoplasty of L1 for pathologic compression fractures. Subsequent cultures revealed M. abscessus. The patient further underwent an anterior T12-L2 corpectomy and debridement with instrumented fusion, as well as a posterior T9-L4 instrumentation and fusion. He received multi-agent antibiotic therapy; however, was ultimately unable to tolerate the aggressive treatment regimen and his prolonged postoperative course.

Discussion

Nontuberculous mycobacteria vertebral osteomyelitis is exceedingly rare. NTM vertebral osteomyelitis is challenging to treat. Surgical management plays a limited role in early VO, but is the mainstay treatment in chronic VO. Early recognition of the condition and shared patient management with multidisciplinary teams is key to successfully treating cases of NTM VO.
A Landsat-based vegetation trend product of the Tibetan Plateau for the time-period 1990–2018
Authors: Fassnacht Fabian Ewald , Schiller Christopher , Kattenborn Teja , Zhao Xinquan , Qu Jiapeng
Published: May 2019

The Tibetan Plateau is a unique, biodiverse ecosystem with an important role in the climate and hydrological system of Asia. Its vegetation supports important functions including fodder provision, erosion prevention and water retention. Assessing vegetation trends of the Tibetan Plateau is crucial to understand effects of recent climate and land-use changes. Most existing vegetation trend products covering the entire Tibetan Plateau have a coarse spatial grain and cover short temporal ranges. This hampers their applicability in studies conducted at local scales where land-use decisions take place and at time scales where climate changes become apparent. Here, we present vegetation trend products for the entire Tibetan Plateau at a spatial resolution of 30 m for the time period 1990–2018. These products include results of a modified Mann-Kendall trend test applied to annual Landsat-based NDVI mosaics, composed from all satellite observations acquired during the vegetation periods as well as NDVI difference images. These data can be valuable to many researchers including for example wildlife ecologists, rangeland experts and climate change researchers.
Periodontal treatment prevents arthritis in mice and methotrexate ameliorates periodontal bone loss
Authors: Lübcke Paul M. , Ebbers Meinolf N. B. , Volzke Johann , Bull Jana , Kneitz Susanne , Engelmann Robby , Lang Hermann , Kreikemeyer Bernd , Müller-Hilke Brigitte
Published: May 2019

Recent studies indicate a causal relationship between the periodontal pathogen P. gingivalis and rheumatoid arthritis involving the production of autoantibodies against citrullinated peptides. We therefore postulated that therapeutic eradication P. gingivalis may ameliorate rheumatoid arthritis development and here turned to a mouse model in order to challenge our hypothesis. F1 (DBA/1 x B10.Q) mice were orally inoculated with P. gingivalis before collagen-induced arthritis was provoked. Chlorhexidine or metronidazole were orally administered either before or during the induction phase of arthritis and their effects on arthritis progression and alveolar bone loss were compared to intraperitoneally injected methotrexate. Arthritis incidence and severity were macroscopically scored and alveolar bone loss was evaluated via microcomputed tomography. Serum antibody titres against P. gingivalis were quantified by ELISA and microbial dysbiosis following oral inoculation was monitored in stool samples via microbiome analyses. Both, oral chlorhexidine and metronidazole reduced the incidence and ameliorated the severity of collagen-induced arthritis comparable to methotrexate. Likewise, all three therapies attenuated alveolar bone loss. Relative abundance of Porphyromonadaceae was increased after oral inoculation with P. gingivalis and decreased after treatment. This is the first study to describe beneficial effects of non-surgical periodontal treatment on collagen-induced arthritis in mice and suggests that mouthwash with chlorhexidine or metronidazole may also be beneficial for patients with rheumatoid arthritis and a coexisting periodontitis. Methotrexate ameliorated periodontitis in mice, further raising the possibility that methotrexate may also positively impact on the tooth supporting tissues of patients with rheumatoid arthritis.