bluuebunny/crossref_metadata_2025 huggingface dataset:
A MARKED COX MODEL FOR THE NUMBER OF IBNR CLAIMS: ESTIMATION AND APPLICATION
Authors: Badescu Andrei L. , Chen Tianle , Lin X. Sheldon , Tang Dameng
Published: May 2019

Incurred but not reported (IBNR) loss reserving is of great importance for Property & Casualty (P&C) insurers. However, the temporal dependence exhibited in the claim arrival process is not reflected in many current loss reserving models, which might affect the accuracy of the IBNR reserve predictions. To overcome this shortcoming, we proposed a marked Cox process and showed its many desirable properties in Badescu et al. (2016).

In this paper, we consider the model estimation and applications. We first present an expectation–maximization (EM) algorithm which guarantees the efficiency of the estimators unlike the moment estimation methods widely used in estimating Cox processes. In addition, the proposed fitting algorithm can be implemented at a reasonable computational cost. We examine the performance of the proposed algorithm through simulation studies. The applicability of the proposed model is tested by fitting it to a real insurance claim data set. Through out-of-sample tests, we find that the proposed model can provide realistic predictive distributions.
Measuring institutional community engagement: Adding value to academic health systems
Authors: Ahmed Syed M. , Neu Young Sharon , DeFino Mia C. , Kerschner Joseph E.
Published: May 2019

Beyond medical schools’ historical focus on pillar missions including clinical care, education, and research, several medical schools now include community engagement (CE) as a mission. However, most academic health systems (AHSs) lack the tools to provide metrics, evaluation, and standardization for quantifying progress and contributions of the CE mission. Several nationwide initiatives, such as that driven by the Institute of Medicine recommending advances in CE metrics at institutions receiving Clinical and Translational Science Awards, have encouraged the research and development of systematic metrics for CE, but more progress is needed. The CE components practical model provides a foundation for analyzing and evaluating different types of CE activities at AHSs through five components: research, education, community outreach and community service, policy and advocacy, and clinical care. At the Medical College of Wisconsin (MCW), an annual survey administered to faculty and staff assessed the types and number of CE activities from the prior year. Survey results were combined to create a CE report for departments across the institution and inform MCW leadership. Insights gathered from the survey have contributed to next steps in CE tracking and evaluation, including the development of a CE dashboard to track CE activities in real time. The dashboard provides resources for how individuals can advance the CE mission through their work and guide CE at the institutional level.
Wind-mediated seed dispersal of invasive forage grasses from agricultural grasslands in Hokkaido, Japan
Authors: Egawa Chika , Shoji Atsushi , Shibaike Hiroyuki
Published: May 2019

Although introduced pasture grasses are essential for forage production in current livestock farming, some species cause serious impacts on native biodiversity when naturalized. Information on the seed dispersal of invasive forage grasses from cultivated settings to surrounding environments can inform management efforts to prevent their naturalization. In this case study, we quantified the wind-mediated seed dispersal distance and amount of dispersed seed of invasive forage grasses from agricultural grasslands in Hokkaido, northern Japan. In total, 200 funnel seed traps were installed around three regularly mown grasslands and one unmown grassland where various forage grass species were grown in mixture. Seeds of each species dispersed outside the grasslands were captured from May to October 2017. Based on the trapped distances of seeds, the 99th percentile dispersal distance from the grasslands was estimated for six species, including timothy (Phleum pratense L.), orchardgrass (Dactylis glomerata L.), and Kentucky bluegrass (Poa pratensis L.). For two dominant species, P. pratense and D. glomerata, the numbers of seeds dispersed outside the field under mown and unmown conditions were determined under various plant cover situations. The estimated dispersal distances ranged from 2.3 m (P. pratense) to 31.5 m (P. pratensis), suggesting that areas within approximately 32 m of the grasslands are exposed to the invasion risk of some forage grass species. For both P. pratense and D. glomerata, the number of seeds dispersed outside the unmown grassland exceeded 100 seeds m−2 under high plant cover situations, while the number of seeds dispersed from the mown grasslands at the same plant cover level was less than one-third of that number. The results suggest that local land managers focus their efforts on frequent mowing of grasslands and monitoring of the areas within approximately 32 m of the grasslands to substantially reduce the naturalization of invasive forage grasses.
Interaction of two-dimensional spots with a heat releasing/absorbing shock wave: linear interaction approximation results
Authors: Farag G. , Boivin P. , Sagaut P.
Published: May 2019

The canonical interaction between a two-dimensional weak Gaussian disturbance (entropy spot, density spot, weak vortex) with an exothermic/endothermic planar shock wave is studied via the linear interaction approximation. To this end, a unified framework based on an extended Kovásznay decomposition that simultaneously accounts for non-acoustic density disturbances along with a poloidal–toroidal splitting of the vorticity mode and for heat release is proposed. An extended version of Chu’s definition for the energy of disturbances in compressible flows encompassing multi-component mixtures of gases is also proposed. This new definition precludes spurious non-normal phenomena when computing the total energy of extended Kovásznay modes. Detailed results are provided for three cases, along with fully general expressions for mixed solutions that combine incoming vortical, entropy and density disturbances.
Paleogeographic and paleoecological significance of Schachriomonia (Brachiopoda) from the Upper Ordovician of the Tarim Basin, Northwest China
Authors: Sproat Colin D. , Zhan Renbin
Published: May 2019

The atrypide brachiopod Schachriomonia is documented here for the first time from the upper Katian Hadabulaktag Formation on the northeastern edge of Tarim Basin in Northwest China. These shells are conspecific with the earlier reported Rhynchotrema pentagonia Fang in Liu and Fang, 1990 from the same region. This species is most similar to Schachriomonia parva Popov et al., 1999 described from the Upper Ordovician of the Chu-Ili and Chingiz terranes and less closely resembles species from North and South China, indicating a close paleogeographic connection between these plates and terranes and Tarim during the Late Ordovician. Its dominance at three horizons in the study area may indicate that this species was an opportunistic colonizer of the seafloor following ecological disruption, or alternatively that the larvae were substrate-selective. Variation in shell shape from a nearly circular shell outline with a dorsal sulcus and ventral fold in the smallest shells to a wider outline with a more reversed dorsal fold and ventral sulcus in the largest is an example of ontogenic development. This may have been an adaptation to accommodate the growing lophophore or development of gonads in the mantle cavity over the life of the brachiopod. A stronger tooth-socket connection in larger shells strengthened the hinge area to better withstand the stresses caused by the mass of a larger shell.
Similarities Between Two-Dimensional and Axisymmetric Vortex Wakes
Authors: Simmons J E L
Published: May 2019

This paper presents results of an investigation of the wake flow of a series of two-dimensional bluff bodies with different boundary-layer separation angles. These results are compared with the results of an earlier investigation of a similar series of axisymmetric bodies. It is found that when the same length scales characterising the wakes that were proposed for the axisymmetric case are used in the current investigation, then there is good agreement between the two cases in the variation of the length scales with boundary-layer separation angle. The universal Strouhal number previously proposed for axisymmetric bodies is derived for the two-dimensional bodies under investigation and is found to remain a constant for the different bodies, but at a different numerical value from that found for the axisymmetric bodies.
Components of Error in Field Experiments with Cotton, Groundnuts, Kenaf and Sesame in the Central Sudan Rainlands. II . Variation in Plant Measurements Through the Season and a Discussion of Surface Drainage as a Source of Variation
Authors: Hack H. R. B.
Published: May 2019

Dry weight, stem and branch length and node number, and flower and fruit number where appropriate, were recorded through the season on cotton, groundnuts, kenaf and sesame in the central rainlands of the Sudan in 1965. For each sampling date variationwithin plotsandbetweenreplicate plots within blocksandtreatmentxblockinteraction have been studied, together with the effect of these components on the magnitude of the residual root mean square in the analysis oftreatmentsxblocks.The main components were usuallywithin plotandbetween replicate plots within blockerrors. Uncontrolled variation was unacceptably great, and was thought to be in large part the result of irregular surface drainage conditions. It seems more likely to be useful to include surface drainage contrasts in field experiments subject to high intensity rainfall on this impermeable clay soil than to attempt to increase precision alone.
Integrated Field and Glasshouse Screening for Environmental Sensitivity in Cowpea (Vigna Unguiculata)
Authors: Summerfield R.J. , Wien H.C. , Minchin F.R.
Published: May 2019

Effects of daylength and night temperature on the onset of flowering of selected cowpea cultivars have been investigated, using automatically controlled glasshouses at Reading. The results show close agreement with those from field trials in Nigeria, wherein low intensity incandescent lighting was used to extend the natural daylength. As the field technique has proved an effective screen for daylength insensitivity, future screening work in glasshouses can be for effects of night temperature on time to first flower and for day temperature on the rate of leaf senescence and components of seed yield. This integrated approach can accelerate the screening of cowpea cultivars for sensitivity to environmental factors over ranges characteristic of the low altitude, humid tropics.
Varietal Responses of Grain Sorghum to Infestation by Heliothis Armigera
Authors: Wilson A.G.L.
Published: May 2019

In experiments conducted in the Ord River Valley, North Western Australia, the extent of egg laying, larval numbers and grain damage from Heliothis armigera was studied with three sorghum varieties of different head densities. Total numbers of eggs laid were similar for each variety, larval infestation was highest on a very dense-headed variety Pickett 932045 and similar in the semi-dense headed RS610 and the open-headed E57 varieties. Greater losses per larva were estimated with varieties E57 and Pickett 932045 than for RS610, where lesser susceptibility was associated with ability to compensate, mainly by increased grain size, for grain loss. This paper reports the results of experiments at Kimberley Research Station to measure infestation and damage caused by H. armigera on three varieties of sorghum with head types ranging from dense to open, and the effectiveness of biological and chemical control practices are also discussed.
A Long-Term Rotational and Manurial Trial in Uganda
Authors: McWalter A. R. , Wimble R. H.
Published: May 2019

Mean yields and average trends with time are given for cotton, finger millet and groundnuts grown in a rotational experiment during the period 1936–64. The experiment, which ran for five cycles, involved a five-year rotation with three different resting periods, five types of resting cover, and farmyard manure at three levels. Yield trends differed from crop to crop, and a critical level of total soil nitrogen is suggested in partial explanation. Responses to farmyard manure in most crops increased over die years, with increasingly marked negative curvature in a pattern that showed most strongly in cotton crops immediately following the application of manure.
The New French Law Against Racial Discrimination and Anti-Semitism
Authors: Klein Claude
Published: May 2019

Great efforts have been made during the last decade to combat all forms of racial discrimination and anti-semitism, by legislation as well as on the social plain. On an international level, special conventions have been adopted, and some countries such as the United States, Great Britain, and Austria have, in addition, adopted special provisions to deal with their own specific problems. The growing number of foreigners who now come to work (Arabs, Africans, Portuguese, Italians, Greeks, Turks etc.) in Western Europe, have aggravated the ever present tradition of racism and anti-semitism, and have produced new forms of racial discrimination. In 1972, France widened the legislation which had been initiated in 1939. A number of cases have already been decided by French courts applying the 1972 law and in this article we will discuss its practical application.
Who is not a Jew?–The Medieval Discussion
Authors: Blidstein Gerald J.
Published: May 2019

While contemporary Jews debate “Whoisa Jew?”, medievals found the question “Who isnota Jew?” much more relevant. Halakhic standards were clear enough on entrance to the community: birth or conversion decided the matter, and the latter provided no more problems than did the average halakhic norm. The institution of conversion was not quite as old as that of birth, but it too had a respectable history of Talmudic discussion and stable international precedent behind it by the start of medieval times, and no Jewry found itself in a quandary on that score. This was not the case regarding Jews who rejected Judaism and left the community. Talmudic discussion is both sparse and incomplete on this issue; and it may not necessarily suit the case of the medieval apostate who exchanges his native fold for an equally possessive faith community. The medievals faced the problem, then, with some Talmudic guidelines but with many open options; yet despite the different opinions that developed, we are able to speak of a medieval concensus. This concensus delivered a legal standard, to be sure; but, as we might expect from an issue of such scope and centrality, the legal concensus was based on a broad understanding of the relation of the Jew to his people and the nature of Jewish peoplehood.
Tax Reform in Israel
Authors: Rafael Amnon E.
Published: May 2019

The Israeli income tax system has been criticized as one of the main causes of the shortcomings of Israeli society. Moral decadence, corruption, disregard for truth, the drive towards materialism, the decline of long-established values, acquiescence in injustice and the widening of the gap between the “haves” and the “have nots”—to name but a few—have been ascribed to it. Rarely has a tax system as such, been credited with the ability to contribute so little good. Admittedly, the tax system became an easy scapegoat to blame for the weaknesses of Israeli society. More than the tax system has gone wrong; the very fibre of Israeli society has come under a strain for which Israelis were ill-prepared. It would therefore be more accurate to describe the Israeli tax scene during the past few years as one of the symptoms of the malady, but not as the sickness itself.
A Tribute to Jean Juster
Authors: Rabello Alfredo M.
Published: May 2019

The Faculty of Law of the Hebrew University of Jerusalem and the Israel Law Review wish to honour the memory of a brilliant young Jewish scholar who was killed in action while fighting for France in the First World War.

Jean Juster born in 1881 at Piatra-Neamtz, in Rumania (Moldavia), was of a family well-known in the region. His grandfather, Abraham Lipa Juster, one of the leaders of the Jewish community, was erudite and active in public affairs. His father, Moshe, was also learned in Jewish studies and active in the promotion of the well-being of the community.

Jean probably received his Jewish education at Piatra. In that town, which N. Sokolow called “the Moldavian Jerusalem”, a branch of the Hovevei Zion movement was created in 1894 and from 1897 groups of supporters of Zionism were active.
Biocontrol of Purple Nutsedge byBactra verutanaZeller in a Greenhouse
Authors: Frick K.E. , Quimby P.C.
Published: May 2019

The degree of control of purple nutsedge (Cyperus rotundusL.) provided byBactra verutanaZeller, a native moth, was evaluated for various stress conditions. Two, three, or four weekly infestations each with three larvae per live shoot, reduced purple nutsedge dry weight an average 77% compared with an average 55% for one infestation. Eight weekly infestations reduced plant dry weight 98%. Neither caging of the larvae on the plants nor osmotic stress with NaCl to −8 bars influenced larval efficacy, but nitrogen deficiency did reduce the effect of the larvae about 75%. Purple nutsedge had no effect on the dry weight of cucumber (Cucumis sativusL., ‘Straight Eight’) after 1 month, whether larvae were or were not present. Purple nutsedge did reduce the plant dry weight of okra (Abelmoschus esculentus(L.) Moench, ‘Clemson Spineless’) 64%, but repeated (eight) weekly infestations of larvae gave a plant weight of okra equal to that of okra grown without purple nutsedge. Purple nutsedge reduced the bulb and root dry weight of onion (Allium cepaL., ‘Big Valley’) 37%, but repeated weekly infestations of larvae gave onion growth equal to that of onion grown without purple nutsedge.
Susceptibility of Pea Cultivars to Trifluralin
Authors: Harvey Robert G. , Gritton Earl T.
Published: May 2019

The relative susceptibility of ‘Alaska’ and ‘Perfection’ cultivars of peas (Pisum sativumL.) to trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) was studied in excised roots, and in greenhouse and field plantings. Elongation of excised Alaska and Perfection pea roots was reduced 32 and 25%, respectively, by 4 mg/L dosages of trifluralin in aseptic culture, and 25 and 10% by 1.68 kg/ha dosages in greenhouse-grown plants. Seedling emergence in the greenhouse and field was reduced or delayed in both cultivars by 1.68 kg/ha trifluralin. Yields of field-grown Alaska and Perfection peas were reduced by trifluralin dosages equal to and exceeding 0.84 and 1.68 kg/ha, respectively, when there was a June water deficit (8 cm). Yields were not reduced in either cultivar when June rainfall was near normal (10.9 cm).
Range Forage Production and Consumption Following Aerial Spraying of Mixed Brush
Authors: Scifres C.J. , Durham G.P. , Mutz J.L.
Published: May 2019

Production of native grasses following aerial application of 1.12 kg/ha of 2.4.5-T ((2,4,5-trichlorophenoxy)acetic acid), 2,4,5-T + dicamba (3,6-dichloro-o-anisic acid), or 2,4,5-T + picloram (4-amino-3,5,6-trichloropicolinic acid) (1:) to a south Texas mixed-brush (Prosopis-Acacia) community was significantly increased by all herbicide treatments the year of application, by the herbicide combinations during the second year, but only by 2,4,5-T + picloram the third year after treatment. Moisture-use efficiency based on kg/ha native grass produced/cm precipitation was greastest where the herbicide combinations were applied. Defoliation of woody plants in years of above-average rainfall resulted in favorable grass production responses regardless of herbicide(s). However, range improvement over the 3-yr of study was dependent on maintenance of herbicide effectiveness, especially control of underbrush which resulted only where 2,4,5-T + picloram were applied. Consumption of native grass was a direct function of availability in response to brush control as augmented by rainfall. Forb production was reduced by all herbicides the year of treatment and by 2,4,5-T + picloram the year following application, but was not reduced by any treatment during the third growing season.
Effect of Trifluralin and Metribuzin Combinations on Soybean Tolerance to Metribuzin
Authors: Ladlie James S. , Meggitt William F. , Penner Donald
Published: May 2019

In field trials, soybeans [Glycine max(L.) Merr.] treated with trifluralin [α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine] at 0.56 and 0.84 kg/ha were protected from injury by metribuzin [4-amino-6-tert-butyl-3-(methylthio-as-triazine-5(4H)one] at 0.28 to 1.12 kg/ha. Soybean injury from metribuzin at high soil pH values was reduced by applying it in combination with trifluralin. Trifluralin also protected soybeans from injury caused by low rates of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] greenhouse studies. The trifluralin treatment reduced root development and greatly reduced14C-atrazine and14C-metribuzin uptake and content within the soybean plant.
Volatility of Eleven Dinitroaniline Herbicides
Authors: Parochetti J. V. , Dec G. W. , Burt G. W.
Published: May 2019

Vapors of 11 dinitroaniline herbicides from soil were trapped in a Florisil column under controlled laboratory conditions for a 3-hr period. No vapor losses of nitralin [4-(methylsulfonyl)-2,6-dinitro-N,N-dipropylaniline] and oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide) were detected at the highest temperature, 50 C, from moist Lakeland sand with an air flow of 50 ml/min; whereas, under the same conditions vapor losses approached 25% for benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine), profluralin [N-(cyclopropylmethyl)-α,α,α-trifluoro-2,6-dinitro-N-propyl-p-toluidine] and trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine). Vapor losses for the remaining herbicides studied were moderate with values ranging between 2 and 13%. Volatility of all herbicides increased with increasing temperatures of 30, 40, and 50 C. Vapor losses for each herbicide from Hagerstown clay loam, Littleton silt loam and Lakeland sand were statistically different for five of the 11 herbicides.
Effects of Temperature on Absorption and Translocation of Profluralin and Dinitramine
Authors: Hawxby K. , Basler E.
Published: May 2019

The absorption, translocation, and metabolism of14C-profluralin [N-(cyclopropylmethyl)-α,α,α-trifluoro-2,6-dinitro-N-propyl-p-toluidine] and14C-dinitramine (N4,N4-diethyl-α,α,α-trifluoro-3,5-dinitrotoluene-2,4-diamine) in sorghum [Sorghum bicolor(L.) Moench ‘RS6–12′], barnyardgrass [Echinochloa crus-galli(L.) Beauv.], soybean [Glycine max(L.) Merr. ‘Dare’], and Palmer amaranth (Amaranthus palmeriS. Wats.) were determined after treatment with14C-labeled herbicides in nutrient solution for 24 hr at 16 or 38 C.14C-profluralin accumulated in roots to a greater extent at 16 C, while metabolism was greatest at 38 C. Very little14C-profluralin was translocated to the tops of plants. Conversely,14C-dinitramine accumulated in the tops of plants to a greater extent at 38 C. Metabolism was not greatly affected by temperature. These effects may relate to excess toxicity of profluralin at 16 C and dinitramine at 38 C in species which normally exhibit resistance to the herbicides.
Absorption, Translocation, and Metabolism of 2,4-D and Glyphosate in Common Milkweed and Hemp Dogbane
Authors: Wyrill J. B. , Burnside O. C.
Published: May 2019

Field and greenhouse studies of 2,4-D [(2,4-dichlorophenoxy)acetic acid] and glyphosate [N-(phosphonomethyl) glycine] absorption, translocation, and metabolism were initiated to explain field observations which indicated susceptibility of common milkweed (Asclepias syriacaL.) but not hemp dogbane (Apocynum cannabinumL.) to glyphosate and the reverse response to 2,4-D. Glyphosate was absorbed less than 2,4-D in both species with absorption of both herbicides being greater in common milkweed. Greater herbicide absorption by common milkweed was attributed to less epicuticular wax, less cuticle, lower contact angle of the herbicide spray, and the presence of stomata and trichomes on the adaxial leaf surface. No major translocation differences of the herbicides were noted between species. Translocation of glyphosate was more rapid than that of 2,4-D. More glyphosate than 2,4-D accumulated in areas of high meristematic and metabolic activity. Rapid 2,4-D metabolism occurred in common milkweed leaves above treated leaves. There was no detectable 2,4-D metabolism in hemp dogbane roots after 20 days, while 60% of the 2,4-D in common milkweed roots was metabolized. Limited absorption of glyphosate but not 2,4-D by hemp dogbane and metabolism of 2,4-D but not glyphosate by common milkweed were considered the primary factors involved in explaining observed susceptibility differences.
Effectiveness of Bentazon Applied at Various Times of the Day
Authors: Doran David L. , Andersen Robert N.
Published: May 2019

Bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-(4) 3H-one 2, 2-dioxide] was applied postemergence to common cocklebur (Xanthium pensylvanicumWallr.) and velvetleaf (Abutilon theophrastiMedic.) at various times of the day in growth chamber and field studies and to soybeans [Glycine max(L.) Merr.] in field studies. Soybeans were tolerant of bentazon regardless of time of day when treated. Results with common cocklebur and velvetleaf suggest that the time of day when bentazon is applied can be of practical importance. Poor control might occur following application in late evening, night, or early morning.
Persistence and Movement of Diuron and 3,4-Dichloroaniline in an Orchard Soil
Authors: Khan S. U. , Marriage P. B. , Saidak W. J.
Published: May 2019

The movement and persistence of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] and its degradation product, 3,4-DCA (3,4-dichloraniline) were studied in an orchard soil which had received diuron annually at the rate of 4.5 kg/ha for 7 yr. Accumulation of residues was not observed at significant levels although carry-over of the herbicide occurred between years. The bulk of the herbicide residue was confined to the upper 15 cm of soil. The degradation rate of diuron generally followed first-order kinetics and the residual levels of diuron in the soil were highly phytotoxic to oat (Avena sativaL.) plants during the 3 yr after the last application. The levels of 3,4-DCA were low in all soil samples (< 21 ppb) and its relative distribution in the soil profile was similar to that of diuron.
Basis for Interactions of Ethofumesate1and Desmedipham on Sugarbeets and Weeds
Authors: Eshel Y. , Zimdahl R.L. , Schweizer E.E.
Published: May 2019

A synergistic interaction occurred when sugarbeets (Beta vulgarisL. ‘Mono-Hy Al’) were treated with mixtures of ethofumesate (2-ethoxy-2,3-dihydro-3,3-dimethyl-5-benzofuranyl methanesulphonate) and desmedipham [ethylm-hydroxycarbanilate carbanilate (ester)]. Depending on the stage of weed growth synergistic interactions were also observed on two weed species: wild mustard [Brassica kaber(DC.) L.C. Wheeler ‘pinnatifida’ (Stokes) L.C. Wheeler] and wild oat (Avena fatuaL.). Desmedipham penetrated the foliage more slowly than did ethofumesate. The rate of desmedipham penetration was positively correlated with the concentration of its formulants (solvents and adjuvants) in the spraying emulsion, and to a lesser extent with the formulants of ethofumesate. Increasing the spray volume also increased desmedipham penetration. None of these factors affected penetration by ethofumesate.14C-labeled ethofumesate and desmedipham did not translocate out of treated leaves regardless of the concentration of formulants or active ingredients. These data suggest that the synergistic interaction is mainly due to the increased penetration by desmedipham when applied with ethofumesate.
Uptake, Distribution, and Degradation of Simazine by Black Walnut and Yellowpoplar Seedlings
Authors: Wichman J. R. , Byrnes W. R.
Published: May 2019

One-year-old and 3-month-old black walnut (Juglans nigra L.) and yellowpoplar (Liriodendron tulipifera L.) seedlings were treated with ring-labeled 14C-simazine [2-chloro-4,6-bis(ethylamino)-s-triazine] in nutrient culture. Simazine uptake was measured and the levels of simazine and its degradation products monitored at 3, 6, and 9 days following treatment for 1-year-old seedlings and at 3, 8, and 13 days for 3-month-old seedlings. Concentration of simazine and the phytotoxic degradation product monodealkylated simazine [2-chloro-4-amino-6-(ethylamino)-s-triazine] were significantly higher in yellowpoplar than in black walnut leaves. For 1-year-old seedlings, higher concentrations of phytotoxic compounds in yellowpoplar than in black walnut were attributed to greater simazine degradation by black walnut. For 3-month-old seedlings, higher concentrations in yellowpoplar were attributed to greater simazine uptake by yellowpoplar and greater degradation in black walnut. Simazine degradation proceeded rapidly in both species and N-dealkylation was a major pathway. Monodealkylated simazine and 2-chloro-4,6-diamino-s-triazine were isolated from various tissues of black walnut and yellowpoplar. Hydroxysimazine [2-hydroxy-4,6-bis(ethylamino)-s-triazine] was found in yellowpoplar roots but not in any black walnut extracts. Two other degradation products were isolated but not identified.
Control of Canada Thistle and Field Bindweed in Asparagus
Authors: Ogg A. G.
Published: May 2019

Canada thistle [Cirsium arvense(L.) Scop.] and field bindweed (Convolvulus arvensisL.) were controlled in asparagus (Asparagus officinalisL. ‘Mary Washington’) fields by repeated applications of dicamba (3,6-dichloro-o-anisic acid) at 0.6 kg/ha or 2,4-D [(2,4-dichlorophenoxy)acetic acid] + dicamba at 1.1 + 0.3 or 1.1 + 0.6 kg/ha. Applications of 2,4-D + dicamba at 1.1 + 0.6 kg/ha in early May and again in mid-June controlled 97% of the Canada thistle in asparagus fields. A third application about August 1 was required to give similar control of field bindweed. Rates of dicamba exceeding 0.6 kg/ha injured the asparagus.
Triallate Granule Spacing Effect on Oat
Authors: Ashford R.
Published: May 2019

Glasshouse experiments were conducted to determine the phytotoxic effect of triallate [S-(2,3,3-trichloroallyl)-diisopropylthiocarbamate] granules on oat (Avena sativaL. ‘Kelsey’). The sphere-of-influence of the granules was found to diminish rapidly with increase in the horizontal distance from the tips of the caryopses. At a distance of 10 mm from the caryopsis tip there was no significant effect on the growth of the oat seedling. The need for the granules to be in close proximity to the developing coleoptile could not be counteracted by increasing the number of granules per caryopsis once the granules were 10 mm or more from the caryopsis. These results give cause to seriously question the generally held belief that triallate disperses through the soil in a volatile phase. Extension of the first leaf and mesocotyl was inhibited much more readily by triallate than coleoptile extension, which was stimulated by a number of treatments. When granules were left on the soil surface of sub-irrigated pots the phytotoxic effect seemed to be mediated through triallate-exposure of the coleoptile tip.
Sorghum Growth as Affected by Annual Applications of Atrazine
Authors: Burnside O. C. , Moomaw R. S.
Published: May 2019

Soil carryover of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] following annual applications to a sorghum [Sorghum bicolor(L.) Moench] monoculture was studied by assessing sorghum yield factors as well as yields of a subsequent bioassay crop of oats (Avena sativaL.). Atrazine applications of 3.4 kg/ha or more increased sorghum injury and rates of 4.5 kg/ha and more increased seed weight and decreased sorghum stand. Sorghum recovered from early atrazine injury and stand loss and generally maintained yields. Rates of 2.2 kg/ha did not reduce sorghum yields even with repeated annual usage. There appears to be little hazard of reducing sorghum yields due to atrazine carryover in the soil from annual atrazine applications at normal rates to a clay loam or silty clay loam soil in eastern Nebraska. However, atrazine carryover will have to be a consideration if the grower plans to rotate to a susceptible crop such as oats.
Comparison of Different Soil Leaching Techniques with Four Herbicides
Authors: Wu Chu-Huang , Santelmann P. W.
Published: May 2019

Herbicide mobility in soils was compared by three laboratory methods. The Rf values calculated from soil thin-layer chromatography correlated closely with those obtained from soil thick-layer chromatography (r = 0.96). Herbicides leached slightly further in slotted column chromatography as compared with the other methods. The working hours required to conduct a study with each method were in the increasing order of thin-layer, thick-layer, and column chromatography. However, the thin-layer method required the longest waiting times, followed by the column and thick-layer chromatography. If radioactive herbicides are not available or obtainable, the thick-layer chromatography is simplest and quickest. The relative mobility of herbicides studied was fluometuron [1,1-dimethyl-3-(α,α,α-trifluoro-m-tolyl)urea] > napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide] > terbutryn [2-(tert-butyl-amino)-4-(ethylamino)-6-(methylthio)-s-triazine] > trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine). Less herbicide mobility was observed in heavier soil than in sandy soil.
Differential Intraspecific Responses of Soybean Cultivars to Bentazon
Authors: Hayes R. M. , Wax L. M.
Published: May 2019

Studies of the differential responses of soybean [Glycine max(L.) Merr.] cultivars to bentazon [3-isopropyl-1H-2,1,3,-benzothiadiazin-(4)3H-one 2,2-dioxide] revealed slightly greater translocation and about a twofold greater foliar absorption in the sensitive cultivar ‘PI 229.342 (Nookishirohana),’ than in the tolerant cultivar, ‘Clark 63.’ Clark 63 metabolized bentazon faster than did PI 229.342. Bentazon was metabolized to unidentified polar metabolites I and II in Clark 63, and only to metabolite II in PI 229.342. The differential absorption and metabolism resulted in a tenfold greater concentration of bentazon in the treated leaflet of PI 229.342 than in that of Clark 63 at 8 days after foliar treatment. Leaflets contained similar amounts of14C in petiole uptake studies, but no bentazon was detected in Clark 63 leaflets 24 hr after pulse treatment, whereas about 20% of the methanol-extractable14C from PI 229.342 leaflets cochromatographed with bentazon. Metabolite I was labile to selected enzymes withβ-glycosidic activity, whereas metabolite II was unaffected. Bentazon concentrations of 30 to 50 μM inhibited O2evolution about 50% in isolated chloroplasts from the two cultivars. Differential bentazon metabolism appears to be the main cause of the differential responses of these soybean cultivars to bentazon.
Influence of Soil Moisture on Tolerance of Corn to Cyanazine
Authors: Kern A. D. , Meggitt W. F. , Penner Donald
Published: May 2019

Tolerance of corn (Zea maysL.) to cyanazine {2-[[4-chloro-6-(ethylamino)-s-triazin-2-yl] amino]-2-methylpropionitrile} and atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] was compared when grown in Conover sandy loam soil. Reductions in seedling dry weight were obtained under both low and high soil moisture following preemergence and postemergence applications of cyanazine allowed to contact both plants and soil. During periods of active plant growth high soil moisture is favorable for rapid root uptake of cyanazine which causes injury to corn.
A Method for Determining the Volatility of Herbicides
Authors: Grover R.
Published: May 2019

The effect of time, flow rate, and temperature on the volatilization of technical grade n-butyl ester of 2,4-D [(2,4-dichlorophenoxy)acetic acid] in a closed air-flow system was evaluated. The amount of ester volatilized was linear with time, at constant temperature and air flow. Volatility increased approximately 8-fold when the temperature was increased from 30 C to 50 C. At 30 C, volatility increased with each doubling of air flow rate from 0.86 nmole/cm2 per hr at 14 L/hr to 1.62 nmole/cm2 per hr at 57.6 L/hr. The effects of temperature, flow rate, and the relationship between vapor pressure and rate of volatilization were also analyzed. The system provided a simple and quantitative method for determining the relative volatilities of both technical and formulated herbicides.
The Effect of Light and Temperature on the Growth and Development of Johnsongrass
Authors: McWhorter C. G. , Jordan T. N.
Published: May 2019

Johnsongrass [Sorghum halepense(L.) Pers.] was grown for 4, 8, and 12 weeks at 24, 32, and 40 C at 9, 13, and 19 klux illumination. Maximum growth and development after 12 weeks were obtained at 32 C and 19 klux. Maximum leaf growth and development were obtained at 32 C and 9 klux. Primary culm height and weight were greater at 24 C than at 40 C, regardless of the illumination, whereas secondary culm height and weight were greater at 40 C than at 24 C. Secondary culm production increased at 40 C and decreased at 24 C. Root and rhizome development increased with increasing light intensity. Growth of roots and rhizomes was maximum at 32 C and minimum at 40 C.
Over-the-top Applications of Herbicides in Cotton
Authors: Arle H. F. , Hamilton K. C.
Published: May 2019

Single and repeat applications of herbicides or herbicide combinations were made over-the-top of young cotton (Gossypium hirsutumL.). DMSA (disodium methanearsonate) and MSMA (monodosium methanearsonate) applied 4 or 8 weeks after emergence had less effect on cotton yield, boll components, and fiber properties than did applications made 12 weeks after emergence. Most single, over-the-top applications of DSMA, fluometuron [1,1-dimethyl-3-(α,α,α-trifluoro-m-tolyl)urea], or DSMA with fluometuron 4 weeks after emergence did not affect cotton yield, boll components, or fiber properties. One or two applications of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] or prometryn [2,4-bis(isopropylamino)-6-(methylthio)-s-triazine] alone, or with DSMA, reduced cotton yields. Applications of 1.1 and 2.2 kg/ha of fluometuron over-the-top of cotton 2 to 8 weeks after emergence did not affect cotton yields, boll components, or fiber properties.
Responses of Weed Populations to Human Manipulations of the Natural Environment
Authors: Young James A. , Evans Raymond A.
Published: May 2019

The occurrence, abundance, and nature of weed communities were reviewed in relation to man's manipulation of the natural environment. Manipulations of the environment necessary for agricultural production have favored secondary successional species. That many of these seral species have opportunistic genotypes has led to the development of weeds. Weeds conform to the concepts of ecologic succession, but agricultural ecosystems are very dynamic with sudden and recurrent changes. The acceleration of successional patterns has provided environments conducive to the selection of competitive genotypes among numerous weeds. Specialized breeding systems provide rapid responses to changing conditions. Weeds increase the diversity of agricultural ecosystems by utilizing environmental potential concentrated for crop production. Weeds have been the shadow of history in that they have mirrored man's activities. The introduction of weed species to new environments may be one of the greatest manipulations of the natural environment, the total consequences of which will be determined in the future.
Germination of Developing Prickly Sida Seeds
Authors: Egley G. H.
Published: May 2019

Freshly-produced, mature prickly sida (Sida spinosaL.) seeds (18 to 21 days after anthesis, < 20% water content) were dormant and neither imbibed water nor germinated when incubated for up to 4 weeks under several light and temperature conditions. Over 80% of the freshly-produced, immature seeds (12 to 16 days after anthesis, > 20% water content) germinated when removed from the mother-plant before dehydration and incubated in alternating 20 to 30 C for 4 weeks. The onset of dormancy coincided with the later stages of seed dehydration and coat-hardening. Over 90% of the mature seeds imbibed water and germinated when incubated at 35 C after 4 months dry storage at 25 C. A puncture through the seed coat, either over the radicle or cotyledons, permitted water imbibition by all mature seeds, but the puncture over the radicle was significantly more effective in inducing germination. Seed coat impermeability was important, but was not the only factor responsible for prickly sida dormancy.
Effects of Adjuvants and Environment on the Toxicity of Dalapon to Johnsongrass
Authors: Mcwhorter C. G. , Jordan T. N.
Published: May 2019

Johnsongrass [Sorghum halepense(L.) Pers.] regrowth was used as an index for penetration and translocation of dalapon (2,2-dichloropropionic acid) with and without adjuvants under different environmental conditions. Johnsongrass control with dalapon at 1.12 kg/ha without surfactant decreased as air temperature increased from 16 to 27 to 38 C. Plants at 16 and 27 C with 100% relative humidity (RH) were more susceptible to dalapon without surfactant than were plants at 35% RH. The presence of 1% surfactant in dalapon solutions increased johnsongrass control above that of dalapon alone at 27 and 38 C regardless of RH. Adding 1% surfactant and maintaining plants at 100% RH and 38 C resulted in significantly less johnsongrass control than that at 35% RH and 38 C. The addition of 0.1 M KH2PO4to mixtures of dalapon + surfactant restored effectiveness at 100% RH and 38 C. Dalapon applied without surfactant was more injurious to johnsongrass grown with 40% soil moisture than with 25% soil moisture regardless of air temperature or RH. When plants were maintained at 27 or 38 C with 25% soil moisture, 0.1 M KH2PO4+ surfactant was more beneficial than surfactant alone in increasing dalapon toxicity to johnsongrass. At 40% soil moisture, johnsongrass control with dalapon + 1 % surfactant was not improved with the addition of KH2PO4regardless of air temperature.
The Identification and Utilization of Weed Biology Information
Authors: Parka S.J.
Published: May 2019

The divisions and subjects of weed biology were identified. Twenty-eight representatives from the herbicide industry ranked the priority of the identified subjects. They also gave their thoughts and impressions on specific questions dealing with weed biology. The divisions which received a moderate to high priority rating are: Identification and Classification of Weeds, Harmful Aspects of Weeds, Weed Growth and Development, and Weed Control. A review of the papers published inWeed Scienceindicates an increase in the number of papers being published on the subject of weed biology and a decrease in the number of papers dealing with chemical control. The proceedings of the regional weed societies in the U.S.A. had a high percent of the papers devoted to chemical control, with the lowest percentage devoted to weed biology. Comments are made as to why weed biology is important and how research data on weed biology would be used by industry. A comparison of the rating that industry assigned to the various subjects of weed biology to the amount of published literature indicates insufficient work has been done in many areas. It also appears that there is an imbalance in research. More work is being done on certain subjects that industry considers of lesser value than subjects of greater importance.
Effect of Weed Species and Placement on Seed Cotton Yields
Authors: Robinson E. L.
Published: May 2019

Over a 3-yr period the placement of weeds in relation to cotton (Gossypium hirsutumL.) plants greatly influenced the seed cotton yields. After 3-yr of competition the cotton with no weeds yielded about 2300 kg/ha. With weeds confined to between-the-rows placement, yields were about 850 kg/ha. When weeds were confined to in-the-row placement, the cotton was completely shaded and produced no yield. After 3-yr of intense competition throughout each entire growing season no statistical differences were demonstrated between the competitiveness of large crabgrass [Digitaria sanguinalis(L.) Scop.], spurred anoda [Anoda cristata(L.) Schlecht.], prickly sida (Sida spinosaL.) and velvetleaf (Abutilon theophrastiMedic.) to cotton.
Dates of Herbicide Application for Summer Weed Control in Turf
Authors: Johnson B. J.
Published: May 2019

Six herbicides were applied monthly from February to May for control of large crabgrass [Digitaria sanguinalis (L.) Scop.] and goosegrass [Eleusine indica (L.) Gaertn.]. Bensulide [O,O-diisopropyl phosphorodithioate S-ester with N-(2-mercaptoethyl)benzenesulfonamide] applied in February or March controlled at least 70% of large crabgrass, whereas, treatments applied in April resulted in similar control at two of three locations. All herbicides failed to control large crabgrass when applied in May. Oxadiazon [2-tert-butyl-4(2,4-dichloro-5-isopropoxyphenyl)-δ2-1,3,4-oxadiazolin-5-one] and butralin [4-(1,1-dimethylethyl)-N-(1-methylpropyl)-2,6-dinitrobenzenamide] controlled goosegrass for the full season when applied in March or April. Oxadiazon also controlled goosegrass when applied in May.
Translocation and Metabolism of Dicamba in Western Bracken
Authors: Robocker W. C. , Zamora B. A.
Published: May 2019

Translocation, distribution, and metabolism of14C-carboxy-labeled dicamba (3,6-dichloro-o-anisic acid) in western bracken [Pteridium aquilinum(L.) Kuhn var.pubescensUnderw.] were determined in field and greenhouse trials by liquid scintillation radioassays, autoradiographs, and paper chromatography. Absorption and translocation of14C readily occurred from14C-labeled dicamba applied to frond buds, pinnae of new leaves, and rhizome tissue. The translocated14C tended to accumulate in opened fronds or if fronds had not emerged, in frond buds and rhizome apices. Dicamba applied to living tissue of a quasi-dormant rhizome in the field in spring was translocated to rhizome apices and metabolized to 5-hydroxy-3,6-dichloro-o-anisic acid and 3,6-dichlorogentisic acid 10 days after application.
Herbicides for No-tillage Corn in Alfalfa Sod
Authors: Moomaw R. S. , Martin A. R.
Published: May 2019

In rolling topography, soil and water runoff losses can be greatly reduced by conservation production systems. Alfalfa (Medicago sativa L.) is an important crop in Nebraska and other states which is often followed in the crop sequence by corn (Zea mays L.) or sorghum [Sorghum bicolor (L.) Moench]. Three years of field experiments indicated that herbicides can substitute for erosive moldboard plowing to destroy alfalfa without loss in the subsequent corn yield. Herbicides applied just prior to corn planting in the spring gave more consistent alfalfa control than those applied the preceeding fall. The most consistent treatment used for alfalfa control and supplemental annual weed control while producing maximum corn yield was 2,4-D amine [(2,4-dichlorophenoxy) acetic acid] plus dicamba (3,6-dichloro-o-anisic acid) at 1.12 and 0.28 kg/ha, respectively. Atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] plus propachlor (2-chloro-N-isopropylacetanilide) versus no preemergence herbicide was used for annual weed control in addition to the treatments to control alfalfa. This treatment was essential for maintaining corn yields where a non-residual or limited residual herbicide was used for alfalfa control.