The regulation of starch accumulation in Panicum maximum Jacq ...

African Journals Online (AJOL)

... decrease the starch level. These observations are discussed in relation to the photosynthetic characteristics of P. maximum. Keywords: accumulation; botany; carbon assimilation; co2 fixation; growth conditions; mesophyll; metabolites; nitrogen; nitrogen levels; nitrogen supply; panicum maximum; plant physiology; starch; ...

Intermediate species measurement during iso-butanol auto-ignition

KAUST Repository

Ji, Weiqi

2015-10-01

© 2015 The Combustion Institute.Published by Elsevier Inc. All rights reserved. This work presents the time histories of intermediate species during the auto-ignition of iso-butanol at high pressure and intermediate temperature conditions obtained using a rapid compression machine and recently developed fast sampling system. Iso-butanol ignition delays were acquired for iso-butanol/O2 mixture with an inert/O2 ratio of 7.26, equivalence ratio of 0.4, in the temperature range of 840-950 K and at pressure of 25 bar. Fast sampling and gas chromatography were used to acquire and quantify the intermediate species during the ignition delay of the same mixture at P = 25.3 bar and T = 905 K. The ignition delay times and quantitative measurements of the mole fraction time histories of methane, ethene, propene, iso-butene, iso-butyraldehyde, iso-butanol, and carbon monoxide were compared with predictions from the detailed mechanisms developed by Sarathy et al., Merchant et al., and Cai et al. It is shown that while the Sarathy mechanism well predicts the overall ignition delay time, it overpredicts ethene by a factor of 6-10, underpredicts iso-butene by a factor of 2, and overpredicts iso-butyraldehyde by a factor of 2. Reaction path and sensitivity analyses were carried out to identify the reactions responsible for the observed inadequacy. The rates of iso-butanol hydrogen atom abstraction by OH radical and the beta-scission reactions of hydroxybutyl radicals were updated based on recently published quantum calculation results. Significant improvements were achieved in predicting ignition delay at high pressures (25 and 30 bar) and the species concentrations of ethene and iso-butene. However, the updated mechanism still overpredicts iso-butyraldehyde concentrations. Also, the updated mechanism degrades the prediction in ignition delay at lower pressure (15 bar) compared to the original mechanism developed by Sarathy et al.

Intermediate species measurement during iso-butanol auto-ignition

KAUST Repository

Ji, Weiqi; Zhang, Peng; He, Tanjin; Wang, Zhi; Tao, Ling; He, Xin; Law, Chung K.

2015-01-01

© 2015 The Combustion Institute.Published by Elsevier Inc. All rights reserved. This work presents the time histories of intermediate species during the auto-ignition of iso-butanol at high pressure and intermediate temperature conditions obtained using a rapid compression machine and recently developed fast sampling system. Iso-butanol ignition delays were acquired for iso-butanol/O2 mixture with an inert/O2 ratio of 7.26, equivalence ratio of 0.4, in the temperature range of 840-950 K and at pressure of 25 bar. Fast sampling and gas chromatography were used to acquire and quantify the intermediate species during the ignition delay of the same mixture at P = 25.3 bar and T = 905 K. The ignition delay times and quantitative measurements of the mole fraction time histories of methane, ethene, propene, iso-butene, iso-butyraldehyde, iso-butanol, and carbon monoxide were compared with predictions from the detailed mechanisms developed by Sarathy et al., Merchant et al., and Cai et al. It is shown that while the Sarathy mechanism well predicts the overall ignition delay time, it overpredicts ethene by a factor of 6-10, underpredicts iso-butene by a factor of 2, and overpredicts iso-butyraldehyde by a factor of 2. Reaction path and sensitivity analyses were carried out to identify the reactions responsible for the observed inadequacy. The rates of iso-butanol hydrogen atom abstraction by OH radical and the beta-scission reactions of hydroxybutyl radicals were updated based on recently published quantum calculation results. Significant improvements were achieved in predicting ignition delay at high pressures (25 and 30 bar) and the species concentrations of ethene and iso-butene. However, the updated mechanism still overpredicts iso-butyraldehyde concentrations. Also, the updated mechanism degrades the prediction in ignition delay at lower pressure (15 bar) compared to the original mechanism developed by Sarathy et al.

Microsatellite markers for the native Texas perennial grass, Panicum hallii (Poaceae).

Science.gov (United States)

Lowry, David B; Purmal, Colin T; Meyer, Eli; Juenger, Thomas E

2012-03-01

We developed microsatellites for Panicum hallii for studies of gene flow, population structure, breeding experiments, and genetic mapping. Next-generation (454) genomic sequence data were used to design markers. Eighteen robust markers were discovered, 15 of which were polymorphic across six accessions of P. hallii var. hallii. Fourteen of the markers cross-amplified in a P. capillare accession. For the 15 polymorphic markers, the total number of alleles per locus ranged from two to 26 (mean: 11.0) across six populations (11-19 individuals per population). Observed heterozygosity (mean: 0.031) was 13.7 times lower than the expected heterozygosity (mean: 0.426). The deficit of heterozygous individuals is consistent with P. hallii having a high rate of self-fertilization. These markers will be useful for studies in P. hallii and related species.

Clinical evaluation and evolution of colic cases associated with Panicum maximum in Mato Grosso State, Brazil

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Renata Gebara Sampaio Dória

2015-12-01

Full Text Available ABSTRACT. Dória R.G.S., Freitas S.H., Laskoski L.M., Carvalho M.B., Monteiro A.O.N., Camplesi A.C. & Valadão C.A.A. [Clinical evaluation and evolution of colic cases associated with Panicum maximum in Mato Grosso State, Brazil.] Avaliação clínica e da evolução dos casos de cólica associados a Panicum maximum no Estado de Mato Grosso, Brasil. Revista Brasileira de Medicina Veterinária, 37(4:303-308, 2015. Departamento de Medicina Veterinária, Curso de Medicina Veterinária, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, Av. Duque de Caxias Norte, 225, Centro, Pirassununga, SP 13635-900, Brasil. E-mail: redoria@usp.br An acute disease characterized by colic and timpanism was reported in Pará and Rondônia after horses fed with Panicum maximum cultivars Momba- ça, Tanzânia and Massai pasture grazing. In this study an acute abdomen case was experimentally reproduced after the ingestion of Panicum maximum var Massai pasture based on twenty two clinic and surgical cases of acute timpanic colic cases reported in a farm in the city of Cuiabá – MT, fed with Panicum maximum var Massai pasture, confirming the etiology and accompanying the clinical evolution of the disease. A horse kept in a stall fed only with Massai pasture was daily evaluated and it was verified that the animal presented as result a clinic perfil of pain, high cardiac frequency, respiratory difficulty, intestinal motility absence and exaggerated distention of the stomach and bowels by gas, seeing during the necropsy the stomach and bowels fully distended by gas with liquefied content except by small colon where the feces presented dry and with mucus characterizing the intestinal atony. The necessity of studies that search the identification of the agent responsible for the intestinal atony and gas accumulation in horses fed with Panicum maximum is exposed.

Acumulación de hojarasca en un pastizal de Panicum maximum y en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala Litter accumulation in a Panicum maximum grassland and in a silvopastoral system of Panicum maximum and Leucaena leucocephala

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Saray Sánchez

2007-09-01

Full Text Available Se realizó un estudio en la Estación Experimental de Pastos y Forrajes "Indio Hatuey", Matanzas, Cuba, con el objetivo de determinar la acumulación de la hojarasca en un pastizal de Panicum maximum Jacq cv. Likoni y en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham. En los pastizales de P. maximum de ambos sistemas se determinó la acumulación de la hojarasca según la técnica propuesta por Bruce y Ebershon (1982, mientras que la hojarasca de L. leucocephala acumulada en el sistema silvopastoril se determinó según Santa Regina et al. (1997. De forma general, los resultados demostraron que en ambos pastizales la guinea acumuló una menor cantidad de hojarasca durante el período junio-diciembre, etapa en la que se produce su mayor desarrollo vegetativo. En la leucaena la mayor producción de hojarasca ocurrió en el período de diciembre a enero, asociada con la caída natural de sus hojas que se produce por efecto de las temperaturas más bajas y la escasa humedad en el suelo. En el sistema silvopastoril la hojarasca de leucaena representó el mayor porcentaje de peso dentro de la producción total, con un contenido más alto de nitrógeno y de calcio que el de la hojarasca del estrato herbáceo. En la guinea la lluvia fue el factor climático que mayor correlación negativa presentó con la producción de hojarasca en ambos sistemas, y en la leucaena la mayor correlación negativa se encontró con la temperatura mínima.A study was carried out at the Experimental Station of Pastures and Forages "Indio Hatuey", Matanzas, Cuba, with the objective of determining the litter accumulation in a pastureland of Panicum maximum Jacq cv. Likoni and in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham. In the P. maximum pasturelands of both systems the litter accumulation was determined by means of the technique proposed by Bruce and Ebershon (1982, while

Producción y calidad del forraje diferido de Panicum coloratum L. en dos periodos de diferimiento y tres momentos de defoliación Production and quality of Panicum coloratum L. deferred forage with two deferred period and three times of defolation

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M.R. Steinberg

2012-06-01

, intermediate (July and late (August. TD produced more dry matter but with a high proportion of stem and more fiber and less protein and ash percentages; while PD had less stem and more leaves and consequently higher percentage of protein and ash. It was concluded that Panicum coloratum is an appropriate fodder to defer only when it is used for a short deferred period and early time of use, because it presents values above 55% digestibility. At this moment Panicum coloratum has a minimum protein level to meet cattle requirements making nitrogen supplementation unnecesary.

Switchgrass (Panicum virgatum L.) as a reinforcing fibre in polypropylene composites

NARCIS (Netherlands)

Oever, van den M.J.A.; Elbersen, H.W.; Keijsers, E.R.P.; Gosselink, R.J.A.; Klerk-Engels, de B.

2003-01-01

In this study the switchgrass (Panicum virgatum L.), a biomass crop being developed in North America and Europe, was tested as a stiffening and reinforcing agent in polypropylene (PP) composites with and without maleic anhydride grafted PP (MAPP) as a compatibiliser and to evaluate the effect of

Macronutrients leaf contents of corn in intercropping with forages of genus Panicum and Urochloa in simultaneous seeding

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Denise Tsuzukibashi

2013-12-01

Full Text Available The planting of crops in degraded pasture areas is a formula used for decades by farmers to recover the productive capacity of pastures and soils. The integrated crop-livestock (ICL consists of different production systems of grains, fibers, wood, meat, milk and agro-deployed in the same area, in intercrop, rotation or succession. Typically this integration mainly involves the planting of grain and pasture in the recovery or deployment. This work aimed to evaluate the macronutrients leaf contents of irrigated corn intercropped with forages of the genus Panicum and Urochloa simultaneously to sown corn. The experiment was conducted at the Farm for Teaching, Research and Extension, Faculty of Engineering - UNESP, Ilha Solteira in an Oxisol in Savannah conditions, in experimental area that had a history of no-tillage to 8 years (previous crop corn. The experimental design used was randomized blocks with four replications and five treatments: Panicum maximum cv. Tanzania sown simultaneously (CTS corn; Panicum maximum cv. Mombaça sown simultaneously (CMS to corn; Urochloa brizantha cv. Xaraes sown simultaneously (CBS corn; Urochloa ruziziensis sown simultaneously (CRS to corn, and corn without intercropping (CWI. The seeds of grasses were sown in spacing of 0.34 m, being sown with a seed drill with disc coulters mounted mechanism for no-tillage system at a depth of 0.03 m. There was no significant difference between the single corn tillage and intercropping with different modalities of forage genus Panicum and Urochloa to the leaf contents of N, P, K, Ca and Mg, demonstrating the non-compete forages with corn in a intercrop on the absorption of these nutrients. In respect to S, CTS presented higher content of S foliar when compared to CWI (Table 1. The absorption of nutrients by corn are not affect by the intercrop with forages of the genus Panicum and Urochloa, in simultaneously sown.

Influência do oeríodo de cultivo de Panicum maximum (cultivar Tanzânia na fitorremediação de solo contaminado com picloram Influence of Panicum maximum cultivation period on phytoremediation of soil contaminated with picloram

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M.L. Carmo

2008-06-01

four periods of soil cultivation with the species Panicum maximum (cv. Tanzania (0, 60, 80 and 100 days and three doses of picloram (0, 80 and 160 g ha-1. At the end of each pre-established time of soil cultivation with the phyto-remediating species, seeds of tomato and soybean plants, used as bio-indicators of picloram presence, were sown on soil. The bio-indicators showed high sensitivity to picloram in soil, as their cultivation was not feasible without a prior phyto-remediation procedure. The previous cultivation of Tanzania for 60 days ensured a satisfactory initial growth of both soybean and tomato plants when the initial contamination level was lower than 80 g ha-1 of picloram. Above this dose, phyto-remediation provided by Tanzânia plants provide a lower soybean and tomato plants growth, indicating that a longer period of decontamination is required.

Preference by horses for bedding pellets made from switchgrass (Panicum virgatum) straw

Science.gov (United States)

The bedding system used for stalled horses can impact their health and well-being. This study examined the saponin concentration in switchgrass (Panicum virgatum) straw, and bedding pellets made from switchgrass straw. Further, this study determined the palatability of bedding pellets made from sw...

Isolation, Characterization, and Quantification of Steroidal Saponins in Switchgrass (Panicum virgatum L.)

Science.gov (United States)

Switchgrass (Panicum virgatum L.) has been identified for development into an efficient and environment friendly biomass energy crop. A recent five-year study demonstrated that switchgrass grown for biofuel production produced 540 percent more energy than what is needed to grow, harvest and process...

The effect of alcoholic extract of Panicum miliaceum L. seed on hippocampus neuronal density in male mouse

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Arezoo Bornarodi

2017-08-01

Full Text Available Background: Hippocampus organization is a part of temporal lobe, which consists of several sections including hippocampal body, dentate gyrus and subiculum. Panicum miliaceum L. contains proteins, vitamins and antioxidants for human health. This study was conducted to examine the effect of the alcoholic extract of the seed of Panicum miliaceum L. plant on hippocampus neuronal density. Materials and Methods: In this experimental study, 24 male mice were divided into 4 groups (n=6, each group. The alcoholic extract of the seed of the Panicum miliaceum L. plant was prepared by soxhlet extraction. Three doses of the extract 25, 50, 75 mg/kg were intraperitoneally injected to 3 treatment groups for 21 days and the control group received normal saline injection. At the end of the experiment, the animals were anesthetized and after perfusion, their brains were removed from the skull. After tissue processing, slices of the brain were prepared and stained. Then, different regions of the hippocampus were photographed and neuronal densities were evaluated. Results: Results showed that the neuronal density in the CA1, CA3 regions of the group treated with 50 mg/kg of the alcoholic extract and in all regions of hippocampus (CA1,CA2,CA3 in groups treated with dose of 75 mg/kg of the alcoholic extract had a significant increase compared to the control group (P<0.05. Conclusion: The present study shows that the alcoholic extract of the seed of Panicum miliaceum L. plant increases neuronal density and induces neurogenesis in the mouse hippocampus.

DISTRIBUTION AND DIVERSITY OF FUSARIUM SPECIES ASSOCIATED WITH GRASSES IN TEN STATES THROUGHOUT PENINSULAR MALAYSIA

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NUR AIN IZZATI, M.Z

2009-01-01

Full Text Available Fusarium is one of the important genera associated with grasses as saprophytes, endophytes and pathogens. A study was carried out on distribution and diversity of Fusarium species associated with two groups of grasses in 10 states throughout Peninsular Malaysia i.e. agricultural grasses (Oryza sativa and Saccharum officinarum and non-agricultural grasses (Axonopus compressus, Centhotheca lappacea, Chloris barbata, Crysopogon aciculatus, Cyanadon dactylon, Dactyloctenium aegyptium, Digitaria ciliaris, Echinochloa colona, Eleusine indica, Eragrostis amabilis, Eragrostis malayana, Eragrostis uniloides, Ischaemum magnum, Panicum brevifolium, Panicum millaneum, Panicum repens, Paspalum commersonii, Paspalum conjugatum, Paspalum orbiculare, Pennisetum purpureum, Sacciolepis indica, Sporobolus diander and Sporobolus indicus. A total of 474 isolates were single-spored and identified by morphological characteristics. F. semitectum was frequently isolated (23.6%, followed by F. sacchari and F. fujikuroi with 15.4% and 14.6%, respectively. The other nine species were F. solani (10.3%, F. proliferatum (8.9%, F. oxysporum (7.4%, F. subglutinans (6.5%, F. equiseti (5.5%, F. verticillioides (3.4%, F. compactum (2.5%, F. chlamydosporum (1.1% and F. longipes (0.8%. Based on the Shannon-Weiner Index, F. solani was the highest (H' = 2.62 isolated from grasses. Species of Fusarium from O. sativa were widely diverse with 11 species, followed by non-agricultural grasses with nine species and S. officinarum with only six species. This is the first report on diversity of Fusarium associated with grasses in Malaysia.

Queilite angular traumática em eqüinos associada à ingestão de Panicum maximum Angular cheilitis in horses associated with ingestion of Panicum maximum

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José Diomedes Barbosa

2009-05-01

Full Text Available Uma condição com aumento da fenda bucal de eqüinos por lesão na comissura labial foi estudada. Este aumento tinha extensão variável e era uni ou bilateral. Na mucosa da bochecha da comissura labial exposta havia pequenas erosões. Durante a mastigação havia perda de pequena quantidade de capim e saliva pela fenda bucal aumentada. Os animais apresentavam bom estado nutricional. O exame histopatológico de tecido retirado da comissura labial revelou epidermite superficial. Nas quatro propriedades onde se verificou o problema, constatou-se que os eqüinos eram mantidos em sistema extensivo de criação em pastagem de Panicum maximum (variedades Tanzânia, Mombaça, Tobiatã e Colonião, com folhas maduras, altas, lignificadas e de bordos cortantes. De acordo com os dados epidemiológicos, com os achados clínicos e histopatológicos, concluí-se que essas lesões foram causadas pela ação cortante das folhas de Panicum maximum, associada à forma de apreensão da pastagem alta e mastigação pelos eqüinos.A condition with enlargement of the oral cleft in horses was studied. The enlargement of varied extension was uni or bilateral. The cheek mucosa of the labial commissure showed slight erosions. During chewing there was loss of small amounts of grass and saliva through the oral cleft. The affected horses were in good nutritional condition. Histopathological studies of tissues obtained by biopsia, revealed a superficial epidermitis. The pastures consisted of Panicum maximum grass (varieties Tanzânia, Mombaça, Tobiatã and Colonião which was mature, tall, lignified, with leaves of cutting edges. Based on epidemiological, clinical and histopathological data, it was concluded that the lesions were caused by the hard grass, favored by the way horses pull the tall grass and chew it.

n-Heptane cool flame chemistry: Unraveling intermediate species measured in a stirred reactor and motored engine

KAUST Repository

Wang, Zhandong; Chen, Bingjie; Moshammer, Kai; Popolan-Vaida, Denisia M.; Sioud, Salim; Shankar, Vijai; Vuilleumier, David; Tao, Tao; Ruwe, Lena; Brä uer, Eike; Hansen, Nils; Dagaut, Philippe; Kohse-Hö inghaus, Katharina; Raji, Misjudeen; Sarathy, Mani

2017-01-01

-OTMS, which has ultra-high mass resolving power and provides an accurate elemental C/H/O composition of the intermediate species. Furthermore, the results show that the species formed during the partial oxidation of n-heptane in the CFR engine are very similar

Ingestion et digestibilité in vivo du Panicum maximum associé à trois compléments: tourteau de Jatophra curcas, tourteau de coton Gossypium hirsutum et Euphorbia heterophylla chez le cobaye Cavia porcellus L

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N'G.D.V. Kouakou

2010-01-01

Full Text Available The Intake and the in vivo Digestibility of Panicum maximum Associated with Three Supplements: Jatophra curcas Cake, Gossypium hirsutum Cake and Euphorbia heterophylla (Euph in Guinea Pigs (Cavia porcellus L.. The intake and the in vivo digestibility of Panicum maximum associated with three supplements: Jatropha curcas cake, Gossypium hirsutum cake and Euphorbia heterophylla (Euph in guinea pigs (Cavia porcellus L. pigs, its association with Panicum maximum could be popularized wherever its abundance has been reported. In order used weed Euphorbia heterophylla in guinea pigs diet, comparative study of the intake and the in vivo digestibility of four treatments, Panicum maximum (Pan, Panicum maximum and Gossypium hirsutum cake (Pancoton, Panicum maximum and Euphorbia heterophylla (Paneuph and Panicum maximum and Jatropha curcas cake (Panjatro, in male guinea pigs were conducted in Yamoussoukro (Ivory Coast. The means of the intake (g DM/d were 64.8 ± 12.5; 74.3 ± 12.9; 73.7 ± 17.8 and 69.1 ± 12.3 respectively for Pan, Pancoton, Paneuph and Panjatro. Pancoton and Paneuph were significantly better ingested than Pan and Panjatro. Euphorbia heterophylla was significantly better ingested than the other two supplements (P< 0.05 and the mean daily weight gain with its association with Panicum maximum of 3.1 ± 0.6 g/d. The rate of substitution of Panicum maximum by Euphorbia heterophylla was nearly to one (1. The apparent digestibility coefficients (ADC for dry (68.0 ± 10.5% and organic matter (84.1 ± 5.2% of Paneuph were significantly higher (P< 0.05 than the ADC's for the other three treatments. Given the nutritional value of Euphorbia heterophylla in guinea pigs, its association with Panicum maximum could be popularized wherever its abundance has been reported.

n-Heptane cool flame chemistry: Unraveling intermediate species measured in a stirred reactor and motored engine

KAUST Repository

Wang, Zhandong

2017-10-03

This work identifies classes of cool flame intermediates from n-heptane low-temperature oxidation in a jet-stirred reactor (JSR) and a motored cooperative fuel research (CFR) engine. The sampled species from the JSR oxidation of a mixture of n-heptane/O2/Ar (0.01/0.11/0.88) were analyzed using a synchrotron vacuum ultraviolet radiation photoionization (SVUV-PI) time-of-flight molecular-beam mass spectrometer (MBMS) and an atmospheric pressure chemical ionization (APCI) Orbitrap mass spectrometer (OTMS). The OTMS was also used to analyze the sampled species from a CFR engine exhaust. Approximately 70 intermediates were detected by the SVUV-PI-MBMS, and their assigned molecular formulae are in good agreement with those detected by the APCI-OTMS, which has ultra-high mass resolving power and provides an accurate elemental C/H/O composition of the intermediate species. Furthermore, the results show that the species formed during the partial oxidation of n-heptane in the CFR engine are very similar to those produced in an ideal reactor, i.e., a JSR.The products can be classified by species with molecular formulae of C7H14Ox (x = 0–5), C7H12Ox (x = 0–4), C7H10Ox (x = 0–4), CnH2n (n = 2–6), CnH2n−2 (n = 4–6), CnH2n+2O (n = 1–4), CnH2nO (n = 1–6), CnH2n−2O (n = 2–6), CnH2n−4O (n = 4–6), CnH2n+2O2 (n = 0–4, 7), CnH2nO2 (n = 1–6), CnH2n−2O2 (n = 2–6), CnH2n−4O2 (n = 4–6), and CnH2nO3 (n = 3–6). The identified intermediate species include alkenes, dienes, aldehyde/keto compounds, olefinic aldehyde/keto compounds, diones, cyclic ethers, peroxides, acids, and alcohols/ethers. Reaction pathways forming these intermediates are proposed and discussed herein. These experimental results are important in the development of more accurate kinetic models for n-heptane and longer-chain alkanes.

Diuretic activity of ethanolic extract of Panicum repens L. roots and rhizomes.

Science.gov (United States)

Hozaien, Hoda E; El-Tantawy, Walid Hamdy; Temraz, Abeer; El-Gindi, Omayma D; Taha, Kamilia F

2018-02-08

The diuretic activity of ethanolic extract of Panicum repens was investigated in rats. A single oral dose of 500 mg/kg of P. repens extract were given to rats, after 24 h, urine volume, its sodium and potassium concentrations were estimated. Treatment with P. repens extract caused a significant increase in tested parameters as compared to their corresponding controls, p < 0.05.

Comparative analysis of lipopolysaccharides of pathogenic and intermediately pathogenic Leptospira species.

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Patra, Kailash P; Choudhury, Biswa; Matthias, Michael M; Baga, Sheyenne; Bandyopadhya, Keya; Vinetz, Joseph M

2015-10-30

Lipopolysaccharides (LPS) are complex, amphipathic biomolecules that constitute the major surface component of Gram-negative bacteria. Leptospira, unlike other human-pathogenic spirochetes, produce LPS, which is fundamental to the taxonomy of the genus, involved in host-adaption and also the target of diagnostic antibodies. Despite its significance, little is known of Leptospira LPS composition and carbohydrate structure among different serovars. LPS from Leptospira interrogans serovar Copenhageni strain L1-130, a pathogenic species, and L. licerasiae serovar Varillal strain VAR 010, an intermediately pathogenic species, were studied. LPS prepared from aqueous and phenol phases were analyzed separately. L. interrogans serovar Copenhageni has additional sugars not found in L. licerasiae serovar Varillal, including fucose (2.7%), a high amount of GlcNAc (12.3%), and two different types of dideoxy HexNAc. SDS-PAGE indicated that L. interrogans serovar Copenhageni LPS had a far higher molecular weight and complexity than that of L. licerasiae serovar Varillal. Chemical composition showed that L. interrogans serovar Copenhageni LPS has an extended O-antigenic polysaccharide consisting of sugars, not present in L. licerasiae serovar Varillal. Arabinose, xylose, mannose, galactose and L-glycero-D-mannoheptose were detected in both the species. Fatty acid analysis by gas chromatography-mass spectrometry (GC-MS) showed the presence of hydroxypalmitate (3-OH-C16:0) only in L. interrogans serovar Copenhageni. Negative staining electron microscopic examination of LPS showed different filamentous morphologies in L. interrogans serovar Copenhageni vs. L. licerasiae serovar Varillal. This comparative biochemical analysis of pathogenic and intermediately pathogenic Leptospira LPS reveals important carbohydrate and lipid differences that underlie future work in understanding the mechanisms of host-adaptation, pathogenicity and vaccine development in leptospirosis.

Accelerating the Switchgrass (Panicum virgatum L.) Breeding Cycle Using Genomic Selection Approaches

Science.gov (United States)

Lipka, Alexander E.; Lu, Fei; Cherney, Jerome H.; Buckler, Edward S.; Casler, Michael D.; Costich, Denise E.

2014-01-01

Switchgrass (Panicum virgatum L.) is a perennial grass undergoing development as a biofuel feedstock. One of the most important factors hindering breeding efforts in this species is the need for accurate measurement of biomass yield on a per-hectare basis. Genomic selection on simple-to-measure traits that approximate biomass yield has the potential to significantly speed up the breeding cycle. Recent advances in switchgrass genomic and phenotypic resources are now making it possible to evaluate the potential of genomic selection of such traits. We leveraged these resources to study the ability of three widely-used genomic selection models to predict phenotypic values of morphological and biomass quality traits in an association panel consisting of predominantly northern adapted upland germplasm. High prediction accuracies were obtained for most of the traits, with standability having the highest ten-fold cross validation prediction accuracy (0.52). Moreover, the morphological traits generally had higher prediction accuracies than the biomass quality traits. Nevertheless, our results suggest that the quality of current genomic and phenotypic resources available for switchgrass is sufficiently high for genomic selection to significantly impact breeding efforts for biomass yield. PMID:25390940

Effet de l'herbe de Guinée ( Panicum maximum Jacq.) associée à l ...

African Journals Online (AJOL)

Effet de l'herbe de Guinée ( Panicum maximum Jacq.) associée à l'herbe de lait ( Euphorbia heterophylla L.) ou aux feuilles de patate douce ( Ipomoea batatas (L.) Lam) sur la croissance des lapins ( Oryctolagus cuniculus L.)

Risk of Soil Recontamination Due to Using Eleusine coracana and Panicum maximum Straw After Phytoremediation of Picloram.

Science.gov (United States)

Nascimento, Alex Favaro; Pires, Fábio Ribeiro; Chagas, Kristhiano; de Oliveira Procópio, Sergio; Oliveira, Marcelo Antonio; Cargnelutti Filho, Alberto; Belo, Alessandra Ferreira; Egreja Filho, Fernando Barboza

2015-01-01

This study aimed to evaluate the herbicidal activity of picloram on the biomass of the remediation plants Eleusine coracana and Panicum maximum after cultivation in a soil contaminated with this herbicide. These species were grown in three soils, differentiated based on texture (clayish, middle, and sandy, with 460, 250, and 40 g kg(-1) of the clay, respectively), previously contaminated with picloram (0, 80, and 160 g ha(-1)). After 90 days, the plants were harvested and an extract was produced by maceration of leaves and stems of these plants. It was applied to pots containing washed sand, comprising a bioassay in a growth chamber using soybean as a bioindicator for picloram. Soil and plant samples were analyzed by HPLC. The results showed the presence of picloram or metabolites with herbicidal activity in the shoots of E. coracana and P. maximum at phytotoxic levels with regard to soybean plants, indicating that they work only as phytoextractors and that the presence of straw on the soil surface can promote recontamination within the area. It is not recommended to cultivate species susceptible to picloram in areas where it was reported remediation by E. indica and P. maximum and still present residues of these species.

Effet de Panicum maximum sur la productivité des femelles primipares durant le cycle de reproduction chez le cobaye (Cavia porcellus L.

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Danho, M.

2012-01-01

Full Text Available Effect of Panicum maximum on Productivity of Primiparous Females during Reproduction Cycle in Guinea Pigs (Cavia porcellus L.. In Ivory Coast, Guinea pigs reared for meat (Cavia porcellus L. are mainly fed with Panicum maximum. To assess the effect of the latter during pregnancy and lactation (RC of these animals, primiparous dams were fed ad libitum, Panicum maximum alone during the RC (MOD1 or associated with pellets for rabbits during lactation (MOD2, or associated with pellets for rabbits during the last part of the pregnancy period and the lactation (MOD3, or associated with pellets for rabbits during the entire RC (MOD4. The number of corpora lutea per female was 1.3 ± 0.5 and 2.0 ± 0.0 respectively for MOD1 and MOD4. No pre-embryonic mortality was recorded. The mean weight of the young guinea pigs of MOD1 (54.7 ± 10. g was only 55% of that of MOD4 (98.6 ± 13.6 g. At weaning, the average weight gain of young guinea pigs of MOD1 (40.5 ± 22.2 g represented a third of those obtained with other diets that did not significantly differ. At the end of RC, the weight gain of dams was 17 ± 13.3% for MOD1 compared to 50% for MOD2, MOD3 and MOD4. Feeding Panicum maximum alone induces chronic malnutrition which in turn is responsible of the low ovulation rate and reduced growth in guinea pig breeding.

Allelopathic Potential of Switchgrass ( Panicum virgatum L.) on Perennial Ryegrass ( Lolium perenne L.) and Alfalfa ( Medicago sativa L.)

Science.gov (United States)

Shui, Junfeng; An, Yu; Ma, Yongqing; Ichizen, Nobumasa

2010-10-01

This study investigated allelopathy and its chemical basis in nine switchgrass ( Panicum virgatum L.) accessions. Perennial ryegrass ( Lolium perenne L.) and alfalfa ( Medicago sativa L.) were used as test species. Undiluted aqueous extracts (5 g plant tissue in 50 ml water) from the shoots and roots of most of the switchgrass accessions inhibited the germination and growth of the test species. However, the allelopathic effect of switchgrass declined when extracts were diluted 5- or 50-fold. Seedling growth was more sensitive than seed germination as an indicator of allelopathic effect. Allelopathic effect was related to switchgrass ecotype but not related to ploidy level. Upland accessions displayed stronger allelopathic potential than lowland accessions. The aqueous extract from one switchgrass accession was separated into phenols, organic acids, neutral chemicals, and alkaloids, and then these fractions were bioassayed to test for allelopathic potential. Alkaloids had the strongest allelopathic effect among the four chemical fractions. In summary, the results indicated that switchgrass has allelopathic potential; however, there is not enough evidence to conclude that allelopathic advantage is the main factor that has contributed to the successful establishment of switchgrass on China’s Loess Plateau.

Selection of full-sib families of Panicum maximum Jacq under low light conditions

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Douglas Mochi Victor

2015-04-01

Full Text Available The silvopastoral system is a viable technological alternative to extensive cattle grazing, however, for it to be successful, forage grass genotypes adapted to reduced light need to be identified. The objective of this study was to select progenies of Panicum maximum tolerant to low light conditions for use in breeding programs and to study the genetic control and performance of some traits associated with shade tolerance. Six full-sib progenies were evaluated in full sun, 50% and 70% of light reduction in pots and subjected to cuttings. Progeny genotypic values ​​(GV increased with light reduction in relation to plant height (H and specific leaf area (SLA. The traits total dry mass accumulation (DM and leaf dry mass accumulation (LDM had GV higher in 50% shade and intermediate in 70% shade. The GV of tiller number (TIL and root dry mass accumulation (RDM decreased with light reduction. The highest positive correlations were obtained for the traits H and RDM with SLA and DM; the highest negative correlations were between TIL and SLA and RDM, and H and LDM. The progenies showed higher tolerance to 50% light reduction and, among them, two stood out and will be used in breeding programs. It was also found that it is not necessary to evaluate some traits under all light conditions. All traits had high broad sense heritability and high genotypic correlation between progenies in all light intensities. There is genetic difference among the progenies regarding the response to different light intensities, which will allow selection for shade tolerance

Complete nucleotide sequences and virion particle association of two satellite RNAs of panicum mosaic virus.

Science.gov (United States)

Pyle, Jesse D; Monis, Judit; Scholthof, Karen-Beth

2017-08-15

Over six decades ago, panicum mosaic virus (PMV) was identified as the first viral pathogen of cultivated switchgrass (Panicum virgatum). Subsequently, PMV was demonstrated to support the replication of both a satellite RNA virus (SPMV) and satellite RNA (satRNA) agents during natural infections of host grasses. In this study, we report the isolation and full-length sequences of two PMV satRNAs identified in 1988 from St. Augustinegrass (Stenotaphrum secundatum) and centipedegrass (Eremochloa ophiuroides) hosts. Each of these satellites have sequence relatedness at their 5'- and 3'-ends. In addition, satC has a region of ∼100 nt complementary to the 3'-end of the PMV genome. These agents are associated with purified virions of SPMV infections. Additionally, satS and satC RNAs contain conserved in-frame open reading frames in the complementary-sense sequences that could potentially generate 6.6- and 7.9-kDa proteins, respectively. In protoplasts and plants satS is infectious, when co-inoculated with the PMV RNA alone or PMV+SPMV RNAs, and negatively affects their accumulation. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of C₃--C₄ intermediate species in the genus Heliotropium L. (Boraginaceae): anatomy, ultrastructure and enzyme activity.

Science.gov (United States)

Muhaidat, Riyadh; Sage, Tammy L; Frohlich, Michael W; Dengler, Nancy G; Sage, Rowan F

2011-10-01

Photosynthetic pathway characteristics were studied in nine species of Heliotropium (sensu lato, including Euploca), using assessments of leaf anatomy and ultrastructure, activities of PEP carboxylase and C₄ acid decarboxylases, and immunolocalization of ribulose 1·5-bisphosphate carboxylase/oxygenase (Rubisco) and the P-subunit of glycine decarboxylase (GDC). Heliotropium europaeum, Heliotropium calcicola and Heliotropium tenellum are C₃ plants, while Heliotropium texanum and Heliotropium polyphyllum are C₄ species. Heliotropium procumbens and Heliotropium karwinskyi are functionally C₃, but exhibit 'proto-Kranz' anatomy where bundle sheath (BS) cells are enlarged and mitochondria primarily occur along the centripetal (inner) wall of the BS cells; GDC is present throughout the leaf. Heliotropium convolvulaceum and Heliotropium greggii are C₃--C₄ intermediates, with Kranz-like enlargement of the BS cells, localization of mitochondria along the inner BS wall and a loss of GDC in the mesophyll (M) tissue. These C₃--C₄ species of Heliotropium probably shuttle photorespiratory glycine from the M to the BS tissue for decarboxylation. Heliotropium represents an important new model for studying C₄ evolution. Where existing models such as Flaveria emphasize diversification of C₃--C₄ intermediates, Heliotropium has numerous C₃ species expressing proto-Kranz traits that could represent a critical initial phase in the evolutionary origin of C₄ photosynthesis. © 2011 Blackwell Publishing Ltd.

Sheep poisoning by Panicum dichotomiflorum in northeastern Brazil Intoxicação por Panicum dicotomiflorum em ovinos na região nordeste

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Franklin Riet-Correa

2009-01-01

Full Text Available Different species of Panicum, including P. dichotomiflorum,have been reported as a cause of photosensitization in sheep, horses, cattle and goats. An outbreak of hepatogenous photosensitization occurred in 3 flocks of hair sheep in the Brazilian semiarid region. Eighty one out of 365 sheep were affected and 39 died. The main affected animals were nursing lambs and sheep younger than one year old. Donkeys, goats and cattle grazing in the same pasture were not affected. Clinical signs were edema of the head, followed by dermatitis, mainly in the face, ears, and croup, ocular discharge, corneal opacity with blindness, and redness of the coronary band and hoof. At necropsy of one affected lamb the liver was yellowish. Upon histologic examination scattered necrotic hepatocytes were observed in the liver and focal areas of necrosis of myocytes appeared in the heart. Samples of P. dicotomiflorum were analyzed by TLC and those containing saponins were isolated by HPLC using RP-C18 column and eluted with a mixture of MeOH and H2O. The isolated compounds were submitted to ¹H and 13C NMR spectroscopy. Reactions were positive to furostanol saponins with the same Rf of the standard protodioscin (0.21 and methylprotodioscin (0.32. The spectroscopic results indicated a mixture of (25R- and (25S-protodioscin isomers in a proportion of 3:1, and methylprotodioscin.Diferentes espécies de Panicum, incluindo P. dichotomiflorum,causam fotossensibilização em ovinos, eqüinos, bovinos e caprinos. Um surto de fotossensibilização hepatógena ocorreu em 3 rebanhos de ovinos no município de Casa Nova, Bahia. Oitenta e um de 365 ovinos adoeceram e 39 morreram. Cordeiros lactentes e ovinos de menos de um ano foram mais afetados. Jumentos, cabras e bovinos que permaneciam nas mesmas pastagens não foram afetados. Clinicamente observou-se edema da face, seguido por dermatite, principalmente da face, orelhas e garupa, corrimento ocular, opacidade da córnea com cegueira

Phytoremediation of biosolids from an end-of-life municipal lagoon using cattail (Typha latifolia L.) and switchgrass (Panicum virgatum L.).

Science.gov (United States)

Jeke, Nicholson N; Hassan, Adenike O; Zvomuya, Francis

2017-03-04

Land spreading of biosolids as a disposal option is expensive and can disperse pathogens and contaminants in the environment. This growth room study examined phytoremediation using switchgrass (Panicum virgatum L.) and cattail (Typha latifolia L.) as an alternative to land spreading of biosolids. Seedlings were transplanted into pots containing 3.9 kg of biosolids (dry wt.). Aboveground biomass (AGB) was harvested either once or twice during each 90-day growth period. Switchgrass AGB yield was greater with two harvests than with one harvest during the first 90-day growth period, whereas cattail yield was not affected by harvest frequency. In the second growth period, harvesting frequency did not affect the yield of either plant species. However, repeated harvesting significantly improved nitrogen (N) and phosphorus (P) uptake by both plants in the first period. Phytoextraction of P was significantly greater for switchgrass (3.9% of initial biosolids P content) than for cattail (2.8%), while plant species did not have a significant effect on N phytoextraction. The trace element accumulation in the AGB of both plant species was negligible. Phytoextraction rates attained in this study suggest that phytoremediation can effectively remove P from biosolids and offers a potentially viable alternative to the disposal of biosolids on agricultural land.

Spectroscopic evidence for intermediate species formed during aniline polymerization and polyaniline degradation.

Science.gov (United States)

Planes, G A; Rodríguez, J L; Miras, M C; García, G; Pastor, E; Barbero, C A

2010-09-21

Spectroscopic methods are used to investigate the formation of low molecular mass intermediates during aniline (ANI) oxidation and polyaniline (PANI) degradation. Studying ANI anodic oxidation by in situ Fourier transform infrared spectroscopy (FTIRS) it is possible to obtain, for the first time, spectroscopic evidence for ANI dimers produced by head-to-tail (4-aminodiphenylamine, 4ADA) and tail-to-tail (benzidine, BZ) coupling of ANI cation radicals. The 4ADA dimer is adsorbed on the electrode surface during polymerization, as proved by cyclic voltammetry of thin PANI films and its infrared spectrum. This method also allows, with the help of computational simulations, to assign characteristic vibration frequencies for the different oxidation states of PANI. The presence of 4ADA retained inside thin polymer layers is established too. On the other hand, FTIRS demonstrates that the electrochemically promoted degradation of PANI renders p-benzoquinone as its main product. This compound, retained inside the film, is apparent in the cyclic voltammogram in the same potential region previously observed for 4ADA dimer. Therefore, applying in situ FTIRS is possible to distinguish between different chemical species (4ADA or p-benzoquinone) which give rise to voltammetric peaks in the same potential region. Indophenol and CO(2) are also detected by FTIRS during ANI oxidation and polymer degradation. The formation of CO(2) during degradation is confirmed by differential electrochemical mass spectroscopy. To the best of our knowledge, this is the first evidence of the oxidation of a conducting polymer to CO(2) by electrochemical means. The relevance of the production of different intermediate species towards PANI fabrication and applications is discussed.

Phytoliths analysis for the discrimination of Foxtail millet (Setaria italica) and Common millet (Panicum miliaceum).

Science.gov (United States)

Lu, Houyuan; Zhang, Jianping; Wu, Naiqin; Liu, Kam-Biu; Xu, Deke; Li, Quan

2009-01-01

Foxtail millet (Setaria italica) and Common millet (Panicum miliaceum) are the oldest domesticated dry farming crops in Eurasia. Identifying these two millets in the archaeobotanical remains are still problematic, especially because the millet grains preserve only when charred. Phytoliths analysis provides a viable method for identifying this important crop. However, to date, the identification of millet phytoliths has been questionable, because very little study has been done on their morphometry and taxonomy. Particularly, no clear diagnostic feature has been used to distinguish between Foxtail millet and Common millet. Here we examined the anatomy and silicon structure patterns in the glumes, lemmas, and paleas from the inflorescence bracts in 27 modern plants of Foxtail millet, Common millet, and closely related grasses, using light microscopy with phase-contrast and microscopic interferometer. Our research shows that five key diagnostic characteristics in phytolith morphology can be used to distinguish Foxtail millet from Common millet based on the presence of cross-shaped type, regularly arranged papillae, Omega-undulated type, endings structures of epidermal long cell, and surface ridgy line sculpture in the former species. We have established identification criteria that, when used together, give the only reliable way of distinguishing between Foxtail millet and Common millet species based on their phytoliths characteristics, thus making a methodological contribution to phytolith research. Our findings also have important implications in the fields of plant taxonomy, agricultural archaeology, and the culture history of ancient civilizations.

Phytoliths analysis for the discrimination of Foxtail millet (Setaria italica and Common millet (Panicum miliaceum.

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Houyuan Lu

Full Text Available Foxtail millet (Setaria italica and Common millet (Panicum miliaceum are the oldest domesticated dry farming crops in Eurasia. Identifying these two millets in the archaeobotanical remains are still problematic, especially because the millet grains preserve only when charred. Phytoliths analysis provides a viable method for identifying this important crop. However, to date, the identification of millet phytoliths has been questionable, because very little study has been done on their morphometry and taxonomy. Particularly, no clear diagnostic feature has been used to distinguish between Foxtail millet and Common millet. Here we examined the anatomy and silicon structure patterns in the glumes, lemmas, and paleas from the inflorescence bracts in 27 modern plants of Foxtail millet, Common millet, and closely related grasses, using light microscopy with phase-contrast and microscopic interferometer. Our research shows that five key diagnostic characteristics in phytolith morphology can be used to distinguish Foxtail millet from Common millet based on the presence of cross-shaped type, regularly arranged papillae, Omega-undulated type, endings structures of epidermal long cell, and surface ridgy line sculpture in the former species. We have established identification criteria that, when used together, give the only reliable way of distinguishing between Foxtail millet and Common millet species based on their phytoliths characteristics, thus making a methodological contribution to phytolith research. Our findings also have important implications in the fields of plant taxonomy, agricultural archaeology, and the culture history of ancient civilizations.

Effect of alfalfa (medicago sativa) on fermentation profile and nutritive value of switchgrass (panicum virgatum) and bermudagrass (cynodon dactylon) silages

Science.gov (United States)

An experiment was conducted at the University of Kentucky Spindletop Farm in Lexington, Kentucky between October and November, 2009 to evaluate the effect of different percentages of alfalfa (Medicago sativa) as mixtures in switchgrass (Panicum virgatus) and bermudagrass (Cynodon dactylon) silages. ...

Characterization of effluent from food processing industries and stillage treatment trial with Eichhornia crassipes (Mart. and Panicum maximum (Jacq.

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N.A. Noukeu

2016-12-01

Full Text Available In this study, effluents from 11 food processing industries from various sectors were characterized through analysis of physical and chemical parameters. In general, effluents pHs are between 4.07 and 7.63. Lead (Pb2+ and cadmium (Cd+ concentrations range from 0.083 to 1.025 mg/l and 0.052–0.158 mg/l respectively. The biodegradability of the effluent is very low. The principal component analysis (PCA grouped industries according to their organic matter levels; thus, stillage, livestock, molasses and sugar refinery effluents show some similarities, as well as confectionery, oil mill, dairy and brewery effluents. Forms of nitrogen measured show low levels of nitrites (NO2−, high levels of nitrates (NO3−, ammonium (NH4+ and Kjeldahl nitrogen (TKN. Among these effluents, a treatment trial with Eichhornia crassipes and Panicum maximum was applied to stillage effluent from Fermencam distillery. The results show that Panicum maximum and Eichhornia crassipes reduce pollutant loads of Fermencam's wastewater.

Biomass and leaf-level gas exchange characteristics of three African savanna C4 grass species under optimum growth conditions

NARCIS (Netherlands)

Mantlana, K.B.; Veenendaal, E.M.; Arneth, A.; Grispen, V.; Bonyongo, C.M.; Heitkönig, I.M.A.; Lloyd, J.

2009-01-01

C4 savanna grass species, Digitaria eriantha, Eragrostis lehmanniana and Panicum repens, were grown under optimum growth conditions with the aim of characterizing their above- and below-ground biomass allocation and the response of their gas exchange to changes in light intensity, CO2 concentration

Alien plant species (ephemerophytes in Romensko-Poltavsky Geobotanical District, Ukraine

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Dvirna Tetyana S.

2017-09-01

Full Text Available This paper presents the results of research on ephemerophytes of the alien portion of the flora of the Romensko-Poltavsky Geobotanical District (north-eastern Ukraine. It is a detailed study of this group of plants, conducted for the first time in the Ukraine. The checklist of alien vascular plants contains 345 species, of which 27 species are ephemerophytes (or 8%: Adonis aestivalis, A. annua, Papaver albiflorum, Urtica cannabina, Gypsophila perfoliata, Atriplex micrantha, Chenopodium × preissmannii, Ch. × thellungii, Rumex longifolius, Sisymbrium polymorphum, Euphorbia humifusa, Malus sylvestris, Onobrychis viciifolia, Astrodaucus orientalis, Datura tatula, Solanum schultesii, Lindernia procumbens, Melampyrum cristatum, Helianthus annuus, Petasites spurius, Xanthium ripicola × Xanthium albinum, Echinochloa tzvelevii, Panicum capillare, Panicum capillare L. subsp. barvipulvinatum, Phalaris canariensis, Setaria ×ambigua, Sorghum halepense. The basis of this work is original data of the author obtained during field studies, and a critical study of the literature, archival, cartographic materials and herbarium collections, and the use of classical methods of botanical classification. Complex research of this group of plants was conducted and as a result of these investigations the following characteristics were established: a predominance of kenophytes of Mediterranean origin in this group, species of arid areas, cosmopolitan species with a diffuse type of space structure, therophytes, herbaceous monocarpic plants, mesotrophes, heliophytes and xeromesophytes, with an insignificant degree of impact on native plant communities and with a limited distribution within the study region. The combination of these results indicates that ephemerophytes comprise a temporary, unstable component of the flora of this region of the Ukraine. The paper provides maps of the distribution of these 27 species.

Seasonal and inter-annual photosynthetic response of representative C4 species to soil water content and leaf nitrogen concentration across a tropical seasonal floodplain

NARCIS (Netherlands)

Mantlana, K.B.; Arneth, A.; Veenendaal, E.M.; Wohland, P.; Wolski, P.; Kolle, O.; Lloyd, J.

2008-01-01

We examined the seasonal and inter-annual variation of leaf-level photosynthetic characteristics of three C4 perennial species, Cyperus articulatus, Panicum repens and Imperata cylindrica, and their response to environmental variables, to determine comparative physiological responses of plants

Effect of Removal of Woody Biomass after Clearcutting and Intercropping Switchgrass (Panicum virgatum with Loblolly Pine (Pinus taeda on Rodent Diversity and Populations

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Matthew M. Marshall

2012-01-01

Full Text Available Plant-based feedstocks have long been considered viable, potential sources for biofuels. However, concerns regarding production effects may outweigh gains like carbon savings. Additional information is needed to understand environmental effects of growing feedstocks, including effects on wildlife communities and populations. We used a randomized and replicated experimental design to examine initial effects of biofuel feedstock treatment options, including removal of woody biomass after clearcutting and intercropping switchgrass (Panicum virgatum, on rodents to 2 years post-treatment in regenerating pine plantations in North Carolina, USA. Rodent community composition did not change with switchgrass production or residual biomass removal treatments. Further, residual biomass removal had no influence on rodent population abundances. However, Peromyscus leucopus was found in the greatest abundance and had the greatest survival in treatments without switchgrass. In contrast, abundance of invasive Mus musculus was greatest in switchgrass treatments. Other native species, such as Sigmodon hispidus, were not influenced by the presence of switchgrass. Our results suggest that planting of switchgrass, but not biomass removal, had species-specific effects on rodents at least 2 years post-planting in an intensively managed southern pine system. Determining ecological mechanisms underlying our observed species associations with switchgrass will be integral for understanding long-term sustainability of biofuels production in southern pine forest.

The complex subcellular distribution of satellite panicum mosaic virus capsid protein reflects its multifunctional role during infection

International Nuclear Information System (INIS)

Qi Dong; Omarov, Rustem T.; Scholthof, Karen-Beth G.

2008-01-01

Satellite panicum mosaic virus (SPMV) depends on its helper Panicum mosaic virus for replication and movement in host plants. The positive-sense single-stranded genomic RNA of SPMV encodes a 17-kDa capsid protein (CP) to form 16-nm virions. We determined that SPMV CP accumulates in both cytosolic and non-cytosolic fractions, but cytosolic accumulation of SPMV CP is exclusively associated with virions. An N-terminal arginine-rich motif (N-ARM) on SPMV CP is used to bind its cognate RNA and to form virus particles. Intriguingly, virion formation is dispensable for successful systemic SPMV RNA accumulation, yet this process still depends on an intact N-ARM. In addition, a C-terminal domain on the SPMV CP is necessary for self-interaction. Biochemical fractionation and fluorescent microscopy of green fluorescent protein-tagged SPMV CP demonstrated that the non-cytosolic SPMV CP is associated with the cell wall, the nucleus and other membranous organelles. To our knowledge, this is the first report that a satellite virus CP not only accumulates exclusively as virions in the cytosol but also is directed to the nucleolus and membranes. That SPMV CP is found both in the nucleus and the cell wall suggests its involvement in viral nuclear import and cell-to-cell transport

New records of Brazilian cicadas including the description of a new species (Hemiptera: Cicadoidea, Cicadidae).

Science.gov (United States)

Sanborn, Allen F

2008-01-01

A new species of Proarna Stål is described from southern Brazil. Proarna gianucai sp. nov. is distinguished by its coloration and genitalia. The species inhabits coastal dune environments and is associated with the perennial grass Panicum racemosum (P. Beauv.) Spreng. Adults are active from December to March. The first records of Carineta durantoni Boulard, Carineta gemella Boulard, Carineta pilifera Walker, Fidicina christinae Boulard & Martinelli, Fidicina torresi Boulard & Martinellli, Fidicinoides determinata (Walker), Fidicinoides distanti (Goding), Fidicinoides glauca (Goding), Majeorona truncata Goding, and Zammara columbia Distant for Brazil are provided. The new species and new records bring the total cicada diversity of Brazil to 146 species.

Efecto de la altura de poda en Leucaena leucocephala y su influencia en el rebrote y rendimiento de Panicum maximum

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H. M. Bacab

2012-01-01

Full Text Available Una de las prácticas importantes de manejo en los sistemas de Leucaena leucocephala asociada con pastos tropicales, como Panicum maximum, es la poda; en la actualidad se continúan los estudios para determinar los efectos de esta práctica en el componente arbóreo y herbáceo. Por todo ello, en el presente trabajo se evaluó el efecto de tres alturas de poda en Leucaena leucocephala cv. Cunningham y su influencia en la pastura asociada (Panicum maximum cv. Tanzania. El estudio se realizó en la época poco lluviosa del año (marzo a mayo de 2010, se utilizó un diseño de bloques completos al azar con cuatro repeticiones. Al inicio del experimento se asignaron los tratamientos (alturas de poda de 20, 40 y 60 cm sobre el nivel del suelo para Leucaena leucocephala. En el caso de Panicum maximum, se realizó una poda a 5 cm sobre el nivel del suelo en todas las parcelas experimentales. Los resultados obtenidos indicaron que la poda de la leguminosa a 40 y 60 cm permitió obtener brotes de mayor talla, sin afectar a la gramínea asociada. De igual manera, al incrementar la altura de poda, la leguminosa presentó mayor rendimiento y proporción de forraje comestible; sin embargo, se afectó negativamente a la pastura asociada. Ante ello, considerándose el aspecto animal, se recomienda no reducir la altura de poda de Leucaena leucocephala a menos de 40 cm, ya que se reduce significativamente el rendimiento y la proporción de forraje comestible de esta leguminosa, el cual es de mayor calidad para la alimentación animal.

Dry Matter Yield And Competitiveness Of Alang-alang (Imperata Cylindrica) And Guinea Grass (Panicum Maximum) In Intercropping

OpenAIRE

Rusdy, M

2012-01-01

The objectives of this experiment were to determine dry matter yield and competitiveness of alang-alang (Imperata cylindrica) and Guinea grass (Panicum maximum) in intercropping. The experiment was arranged in factorial combinations of four planting proportions, two levels of nitrogen fertilization and three harvesting intervals with three replications. Planting proportions were 0, 33.3, 66.7, and 100% of alang-alang (planting densities of 0, 1, 2 and 3 plants/pot) combined with 100, 66.7, 33...

Spectroscopic studies of neutral and chemically oxidized species of β-carotene, lycopene and norbixin in CH2Cl2: Fluorescence from intermediate compounds

International Nuclear Information System (INIS)

Alwis, D.D.D.H; Chandrika, U.G.; Jayaweera, P.M.

2015-01-01

Radical cations, dications and oxidized intermediate species of three carotenoids, namely, β-carotene, lycopene and norbixin, were generated in CH 2 Cl 2 solutions via chemical oxidation using anhydrous FeCl 3 . UV–vis, fluorescence and fluorescence-excitation spectroscopic studies were performed to understand and compare the nature of intermediate species generated during the chemical oxidation process and subsequent degradation. The intense emission observed at 550 nm can be assigned to the S 2 →S 0 (1 1 B u →1 1 A g ) transition of the carotenoid molecules. The 350 nm excitation during the oxidation process for β-carotene, lycopene and norbixin exhibit intense fluorescence peaks at 492 nm, 493 nm and 500 nm, respectively. These peaks are assigned to intermediate peroxy/epoxy compounds of the three molecules that are formed with molecular oxygen prior to the formation of oxidized short-chain stable compounds. - Highlights: • Fluorescence and UV–vis studies on β-carotene, lycopene and norbixin. • Oxidation, induced by FeCl 3 in CH 2 Cl 2 shows blue shifted fluorescence peaks. • Fluorescence peaks were assigned to intermediate peroxy/epoxy forms of carotenoids. • The D0→D3 transition of radical cations are observed in the near IR region

Análise de repetibilidade de caracteres forrageiros de genótipos de Panicum maximum, avaliados com e sem restrição solar Repeatability analysis of forage traits of Panicum maximum genotypes evaluated under natural and attenuated solar radiation

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Alberto Cargnelutti Filho

2004-06-01

Full Text Available O objetivo do trabalho foi determinar o número de medições necessárias à predição do desempenho de cinco genótipos de Panicum maximum Jacq. Os genótipos (Gatton, Vencedor, Mombaça, Tanzânia e Tobiatã foram avaliados sob os sistemas de cultivo com e sem restrição solar, na Fundação Estadual de Pesquisa Agropecuária, situada em Tupanciretã - Rio Grande do Sul. No sistema de cultivo com restrição solar, os genótipos foram avaliados sob um bosque de eucalipto. Em cada uma das oito medições (cortes, foram avaliadas a matéria seca total, matéria seca de folhas, matéria seca de colmo, matéria seca folha + colmo, altura de planta e relação matéria seca folha/colmo. As estimativas dos coeficientes de repetibilidade foram obtidas por três métodos - análise da variância, componentes principais e análise estrutural. Concluiu-se que os oito cortes possibilitaram selecionar genótipos superiores em relação a todas as características, com 80% de exatidão no prognóstico de seu valor real.The objective of this study was to determine how many evaluations were necessary to predict the performance of Panicum maximum Jacq. genotypes. The genotypes Gatton, Vencedor, Mombaça, Tanzânia, and Tobiatã were evaluated under natural and attenuated solar radiation at the Fundação Estadual de Pesquisa Agropecuária, Tupanciretã, RS. Attenuated solar radiation was obtained when plants were grown in Eucalyptus woods. Genotypes in both crop systems were evaluated eight times. Total dry matter production, leaf, stem, and leaf plus stem dry matter, plant height and index of leaf and stem dry matter were recorded each evaluation time. Repeatability estimations were obtained through variance, structural, and principal component analysis. In conclusion, eight evaluations permit to select superior Panicum maximum genotypes, considering all characteristics, with 80% accuracy of the real value.

Oxoferryl-Porphyrin Radical Catalytic Intermediate in Cytochrome bd Oxidases Protects Cells from Formation of Reactive Oxygen Species*

Science.gov (United States)

Paulus, Angela; Rossius, Sebastiaan Gijsbertus Hendrik; Dijk, Madelon; de Vries, Simon

2012-01-01

The quinol-linked cytochrome bd oxidases are terminal oxidases in respiration. These oxidases harbor a low spin heme b558 that donates electrons to a binuclear heme b595/heme d center. The reaction with O2 and subsequent catalytic steps of the Escherichia coli cytochrome bd-I oxidase were investigated by means of ultra-fast freeze-quench trapping followed by EPR and UV-visible spectroscopy. After the initial binding of O2, the O–O bond is heterolytically cleaved to yield a kinetically competent heme d oxoferryl porphyrin π-cation radical intermediate (compound I) magnetically interacting with heme b595. Compound I accumulates to 0.75–0.85 per enzyme in agreement with its much higher rate of formation (∼20,000 s−1) compared with its rate of decay (∼1,900 s−1). Compound I is next converted to a short lived heme d oxoferryl intermediate (compound II) in a phase kinetically matched to the oxidation of heme b558 before completion of the reaction. The results indicate that cytochrome bd oxidases like the heme-copper oxidases break the O–O bond in a single four-electron transfer without a peroxide intermediate. However, in cytochrome bd oxidases, the fourth electron is donated by the porphyrin moiety rather than by a nearby amino acid. The production of reactive oxygen species by the cytochrome bd oxidase was below the detection level of 1 per 1000 turnovers. We propose that the two classes of terminal oxidases have mechanistically converged to enzymes in which the O–O bond is broken in a single four-electron transfer reaction to safeguard the cell from the formation of reactive oxygen species. PMID:22287551

Investigation of RNA structure in satellite panicum mosaic virus

International Nuclear Information System (INIS)

Makino, D.L.; Day, J.; Larson, S.B.; McPherson, A.

2006-01-01

Three new crystal forms of satellite panicum mosaic virus (SPMV) were grown and their structures solved from X-ray diffraction data using molecular replacement techniques. The crystals were grown under conditions of pH and ionic strength that were appreciably different then those used for the original structure determination. In rhombohedral crystals grown at pH 8.5 and low ionic strength PEG 3350 solutions, Fourier syntheses revealed segments, ten amino acid residues long, of amino-terminal polypeptides not previously seen, as well as masses of electron density within concavities on the interior of the capsid, which appeared in the neighborhoods of icosahedral five- and threefold axes. The densities were compatible with secondary structural domains of RNA, and they included a segment of double helical RNA of about four to five base pairs oriented, at least approximately, along the fivefold axes. The distribution of RNA observed for SPMV appears to be distinctly different than the encapsidated nucleic acid conformation previously suggested for another satellite virus, satellite tobacco mosaic virus. This study further shows that analysis of viruses in crystals grown under different chemical conditions may reveal additional information regarding the structure of encapsidated RNA

Imbalanced carbon-for-phosphorus exchange between European arbuscular mycorrhizal fungi and non-native Panicum grasses-A case of dysfunctional symbiosis

Czech Academy of Sciences Publication Activity Database

Řezáčová, Veronika; Slavíková, Renata; Konvalinková, Tereza; Hujslová, Martina; Gryndlerová, Hana; Gryndler, Milan; Püschel, David; Jansa, Jan

2017-01-01

Roč. 62, May 2017 (2017), s. 48-55 ISSN 0031-4056 R&D Projects: GA MŠk(CZ) LK11224; GA ČR(CZ) GA14-19191S Grant - others:AV ČR(CZ) Fellowship J. E. Purkyně Institutional support: RVO:61388971 Keywords : Arbuscular mycorrhiza * Panicum * Plant biomass Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.000, year: 2016

CINÉTICA DE DEGRADABILIDAD in vitro DE CUATRO VARIEDADES DE Panicum maximum COSECHADAS A CUATRO EDADES

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Juan Humberto Avellaneda Cevallos

2015-12-01

Full Text Available Se evaluó la degradabilidad in vitro de la materia seca (MS de las hojas, tallos y planta completa de cuatro variedades de pasto Guinea (Panicum maximum: Común, Tanzania, Enano y Tobiata en cuatro edades de cosecha (21, 42, 63 y 84 d. Se evaluó la composición química de las variedades. Para la digestibilidad in vitro, se empleó la primera fase de la técnica de Tilley y Terry, para lo cual se extrajo líquido ruminal de dos bovinos Brown Swiss canulados a rumen. Se evaluaron seis periodos de incubación (3, 6, 12, 24, 48 y 72 h. Para la cinética de degradación in vitro, se aplicó un diseño de bloques completos al azar (DBCA, utilizando a la corrida (2 como criterio de bloqueo y repetición; se usó una incubadora DaisyII 200 y una bolsita de degradabilidad por corrida. Se observó que la mejor degradabilidad in vitro se presenta en los primeros estadios fenológicos, y que las hojas demuestran mayores características nutricionales, seguida de la planta completa y tallos. Se demostró que las diferencias en degradabilidad no están fuertemente asociadas con la variedad de Panicum maximum, sino más bien con la edad de cosecha. Por lo que se concluye, que la degradabilidad in vitro de las variedades de pasto Guinea, difieren en función del estado de madurez de la planta.

Paracetamol degradation intermediates and toxicity during photo-Fenton treatment using different iron species.

Science.gov (United States)

Trovó, Alam G; Pupo Nogueira, Raquel F; Agüera, Ana; Fernandez-Alba, Amadeo R; Malato, Sixto

2012-10-15

The photo-Fenton degradation of paracetamol (PCT) was evaluated using FeSO(4) and the iron complex potassium ferrioxalate (FeOx) as iron source under simulated solar light. The efficiency of the degradation process was evaluated considering the decay of PCT and total organic carbon concentration and the generation of carboxylic acids, ammonium and nitrate, expressed as total nitrogen. The results showed that the degradation was favored in the presence of FeSO(4) in relation to FeOx. The higher concentration of hydroxylated intermediates generated in the presence of FeSO(4) in relation to FeOx probably enhanced the reduction of Fe(III) to Fe(II) improving the degradation efficiency. The degradation products were determined using liquid chromatography electrospray time-of-flight mass spectrometry. Although at different concentrations, the same intermediates were generated using either FeSO(4) or FeOx, which were mainly products of hydroxylation reactions and acetamide. The toxicity of the sample for Vibrio fischeri and Daphnia magna decreased from 100% to less than 40% during photo-Fenton treatment in the presence of both iron species, except for D. magna in the presence of FeOx due to the toxicity of oxalate to this organism. The considerable decrease of the sample toxicity during photo-Fenton treatment using FeSO(4) indicates a safe application of the process for the removal of this pharmaceutical. Copyright © 2012 Elsevier Ltd. All rights reserved.

Synchrotron photoionization mass spectrometry study of intermediates in fuel-rich 1,2-dimethoxyethane flame

International Nuclear Information System (INIS)

Lin, Z. K.; Han, D. L.; Li, S. F.; Li, Y. Y.; Yuan, T.

2009-01-01

Intermediates in a fuel-rich premixed laminar 1,2-dimethoxyethane (DME) flame are studied by molecular beam mass spectrometry combined with tunable synchrotron vacuum ultraviolet photoionization. About 30 intermediate species are identified in the present work, and their mole fraction profiles are evaluated. The experimental results show that the formations of intermediates, both hydrocarbons and oxygenated hydrocarbons, are closely linked to the structure of fuel, which is consistent with the previous reports. Species produced from H atom abstraction and beta scission of DME usually have much higher concentrations than others. The oxygen atoms in DME are considered to act as partitions of the primary intermediates; therefore farther reactions among these primary intermediates are difficult to occur, resulting in absence of most large intermediate species.

Patogenicidade de Helminthosporium oryzae a algumas espécies de gramíneas Pathogenicity of Helminthosporium oryzae against some grass species

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V.H. Artigiani Filho

1995-04-01

Full Text Available O fungo Helminthosporium oryzae é um patógeno do arroz. Devido a sua variabilidade patogênica, foi investigada a possibilidade deste fungo infectar outras gramíneas. Através de inoculação artificial, ficou demonstrada a capacidade deste patógeno provocar infecção em aveia, cana, centeio, sorgo, trigo, Brachiaria decumbens e Panicum maximum. Assim, estas espécies vegetais podem ser consideradas potenciais hospedeiros do fungo na natureza.Helminthosporium oryzae is a rice pathogen. Due to its variability in pathogenicity, the possibility of this fungus Infecting other grasses was investigated. The capacity of this pathogen was demonstrated to be able to infect oat, sugar-cane, rye, sorghum, wheat, Brachiaria decumbens and Panicum maximum through artificial inoculations. Therefore, those plant species can be considered potencial hosts for the fungus in nature.

Impacts of Panicum maximum Jacq. invasion and its manual weeding on the wood plant regeneration in the understory of a restoration site Efeitos da invasão por Panicum maximum Jacq. e do seu controle manual sobre a regeneração de plantas lenhosas no sub-bosque de um reflorestamento

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Gabriela Ribeiro de Andrade

2012-06-01

Full Text Available Responsible for considerable annual losses of biodiversity in natural ecosystems, invasive alien species cause important conservation problems, leading native species to local extinction. This study examined the relationship among the coverage of Guinea-grass (Panicum maximum Jacq., its manual weeding and the woody plant diversity of a restoration site. The site is a reforestation created using native species but due to spacing and species composition grass still dominates its understory more than 17 years after. Preliminary results showed that it is a barrier to the establishment of native species. In this study, we established 20 plots of 5m x 5m divided into two treatments, control and removal of P. maximum, to investigate the impact of manual weeding on the understory in a period of 90 days. Grass cover and canopy openness were also recorded. The grass cover had negative correlation with the abundance of plants, with the species richness and abundance of tree species. Canopy openness had a negative influence on the species richness, on abundance and richness of tree species, but not showed correlation with P. maximum. After grass removal, both abundance of seedling and species richness had no significant differences, so the manual weeding did not cause a negative impact in short time on the regeneration of the understory due to accidental native plant uprooting. However, a positive impact is expected only after a longer period of observation, after successive removals of invasive herbaceous and increased chance of colonization of the area by regenerating seedlings.Responsáveis por perdas anuais consideráveis na biodiversidade dos ecossistemas naturais, as espécies exóticas invasoras causam sérios problemas à conservação, levando muitas espécies à extinção local. Este estudo analisou o efeito da cobertura de capim-colonião (Panicum maximum Jacq. no sub-bosque de um reflorestamento dominado há mais de 17 anos por essa gram

Physiological Evaluation of Alkali-Salt Tolerance of Thirty Switchgrass (Panicum virgatum Lines.

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Guofu Hu

Full Text Available Soil salt-alkalization is a major limiting factor for crop production in many regions. Switchgrass (Panicum virgatum L. is a warm-season C4 perennial rhizomatous bunchgrass and a target lignocellulosic biofuel species. The objective of this study was to evaluate relative alkali-salt tolerance among 30 switchgrass lines. Tillers of each switchgrass line were transplanted into pots filled with fine sand. Two months after transplanting, plants at E5 developmental stage were grown in either half strength Hoagland's nutrient solution with 0 mM Na+ (control or half strength Hoagland's nutrient solution with 150 mM Na+ and pH of 9.5 (alkali-salt stress treatment for 20 d. Alkali-salt stress damaged cell membranes [higher electrolyte leakage (EL], reduced leaf relative water content (RWC, net photosynthetic rate (Pn, stomatal conductance (gs, and transpiration rate (Tr. An alkali-salt stress tolerance trait index (ASTTI for each parameter was calculated based on the ratio of the value under alkali-salt stress and the value under non-stress conditions for each parameter of each line. Relative alkali-salt tolerance was determined based on principal components analysis and cluster analysis of the physiological parameters and their ASTTI values. Significant differences in alkali-salt stress tolerance were found among the 30 lines. Lowland lines TEM-SEC, Alamo, TEM-SLC and Kanlow were classified as alkali-salt tolerant. In contrast, three lowland lines (AM-314/MS-155, BN-13645-64 and two upland lines (Caddo and Blackwell-1 were classified as alkali-salt sensitive. The results suggest wide variations exist in alkali-salt stress tolerance among the 30 switchgrass lines. The approach of using a combination of principal components and cluster analysis of the physiological parameters and related ASTTI is feasible for evaluating alkali-salt tolerance in switchgrass.

Targeted mutagenesis in tetraploid switchgrass (Panicum virgatum L.) using CRISPR/Cas9.

Science.gov (United States)

Liu, Yang; Merrick, Paul; Zhang, Zhengzhi; Ji, Chonghui; Yang, Bing; Fei, Shui-Zhang

2018-02-01

The CRISPR/Cas9 system has become a powerful tool for targeted mutagenesis. Switchgrass (Panicum virgatum L.) is a high yielding perennial grass species that has been designated as a model biomass crop by the U.S. Department of Energy. The self-infertility and high ploidy level make it difficult to study gene function or improve germplasm. To overcome these constraints, we explored the feasibility of using CRISPR/Cas9 for targeted mutagenesis in a tetraploid cultivar 'Alamo' switchgrass. We first developed a transient assay by which a non-functional green-fluorescent protein gene containing a 1-bp frameshift insertion in its 5' coding region was successfully mutated by a Cas9/sgRNA complex resulting in its restored function. Agrobacterium-mediated stable transformation of embryogenic calli derived from mature caryopses averaged a 3.0% transformation efficiency targeting the genes of teosinte branched 1(tb1)a and b and phosphoglycerate mutase (PGM). With a single construct containing two sgRNAs targeting different regions of tb1a and tb1b genes, primary transformants (T0) containing CRISPR/Cas9-induced mutations were obtained at frequencies of 95.5% (tb1a) and 11% (tb1b), respectively, with T0 mutants exhibiting increased tiller production. Meanwhile, a mutation frequency of 13.7% was obtained for the PGM gene with a CRISPR/Cas9 construct containing a single sgRNA. Among the PGM T0 mutants, six are heterozygous and one is homozygous for a 1-bp deletion in the target region with no apparent phenotypical alterations. We show that CRISPR/Cas9 system can generate targeted mutagenesis effectively and obtain targeted homozygous mutants in T0 generation in switchgrass, circumventing the need of inbreeding. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Physiological Evaluation of Alkali-Salt Tolerance of Thirty Switchgrass (Panicum virgatum) Lines.

Science.gov (United States)

Hu, Guofu; Liu, Yiming; Zhang, Xunzhong; Yao, Fengjiao; Huang, Yan; Ervin, Erik H; Zhao, Bingyu

2015-01-01

Soil salt-alkalization is a major limiting factor for crop production in many regions. Switchgrass (Panicum virgatum L.) is a warm-season C4 perennial rhizomatous bunchgrass and a target lignocellulosic biofuel species. The objective of this study was to evaluate relative alkali-salt tolerance among 30 switchgrass lines. Tillers of each switchgrass line were transplanted into pots filled with fine sand. Two months after transplanting, plants at E5 developmental stage were grown in either half strength Hoagland's nutrient solution with 0 mM Na+ (control) or half strength Hoagland's nutrient solution with 150 mM Na+ and pH of 9.5 (alkali-salt stress treatment) for 20 d. Alkali-salt stress damaged cell membranes [higher electrolyte leakage (EL)], reduced leaf relative water content (RWC), net photosynthetic rate (Pn), stomatal conductance (gs), and transpiration rate (Tr). An alkali-salt stress tolerance trait index (ASTTI) for each parameter was calculated based on the ratio of the value under alkali-salt stress and the value under non-stress conditions for each parameter of each line. Relative alkali-salt tolerance was determined based on principal components analysis and cluster analysis of the physiological parameters and their ASTTI values. Significant differences in alkali-salt stress tolerance were found among the 30 lines. Lowland lines TEM-SEC, Alamo, TEM-SLC and Kanlow were classified as alkali-salt tolerant. In contrast, three lowland lines (AM-314/MS-155, BN-13645-64) and two upland lines (Caddo and Blackwell-1) were classified as alkali-salt sensitive. The results suggest wide variations exist in alkali-salt stress tolerance among the 30 switchgrass lines. The approach of using a combination of principal components and cluster analysis of the physiological parameters and related ASTTI is feasible for evaluating alkali-salt tolerance in switchgrass.

Invertebrate fauna associated with Torpedograss, Panicum repens (Cyperales: Poaceae), in Lake Okeechobee, Florida, and prospects for biological control

International Nuclear Information System (INIS)

Cuda, J.P.; Dunford, J.C.; Leavengood, J.M. Jr.

2007-01-01

Torpedograss, Panicum repens L., is an adventive, rhizomatous grass species that has become an invasive weed of terrestrial, wetland, and aquatic environments in tropical and subtropical regions worldwide. Until recently, strategies for controlling torpedograss in the USA have focused almost exclusively on mechanical and chemical methods, either alone or in combination, with varied results. A survey of the arthropods and nematodes currently associated with the plant in Lake Okeechobee, Florida, was conducted as part of a feasibility study to determine whether torpedograss is an appropriate target for a classical biological control program. Overall, approximately 4,000 arthropods and 400 nematode specimens were collected. Sweep, clipped vegetation, and soil core samples were dominated by representatives of the arthropod orders Hemiptera, Hymenoptera, Diptera, and Acari. Lesion nematodes of the genus Pratylenchus were commonly associated with the roots of torpedograss. None of the organisms collected were torpedograss specialists. Although classical biological control of torpedograss is feasible based on the extent of the infestation, economic losses, resistance to conventional controls, and the report of a potentially host specific natural enemy in India, the botanical position of this grass weed will require a formal risk assessment before proceeding with a classical biological control program. (author) [es

Total number of tillers of different accessions of Panicum maximum Jacq.

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Thiago Perez Granato

2012-12-01

Full Text Available The productivity of forage grasses is due to continuous emission of leaves and tillers, ensuring the restoration of leaf área after cutting or grazing, thus ensuring the sustainability of forage. This study aimed to asses the total number tillers in different acessions of Panicum maximum Jacq. The experiment was carried in field belonging to the Instituto de Zootecnia located in Nova Odessa / SP. Evaluated two new accesses Panicum maximum, and two commercial cultivars. The cultivars tested were Aruana, Milenio, NO 2487, NO 78, and the two latter belonging to the Germoplasm Collection of the IZ. The experimental desing was in randomized complete block with four replications. The experimental area consisted of 16 plots of 10 m2 (5 x 2 m each. The experimental area was analyzed and according to the results, received dolomitic limestone corresponding 2t /ha, two months before the implementation of the experiment. Sowing was made by broad costing together with 80 kg/ha of P2O5 in the form of single superphosfate. After 60 days of implantation of the experiment it was a made a leveling of the plots to a height of about 15 cm. After this it was applied 250g of the 20-00-20 fertilizer/plot. Thirty days after the standardization it was evaluated the total number of tillers of the cultivars, using a metal frame of 0.5 x 0.5m which was thrown at random on each of the 16 plots, leaving one meter of each extremitly, and all tillers which were within the frame counted. After finished the counting of all tillers, the plots cut again at a height of approximately 15 cm. The second evaluation took place after thirty days, and it was again counted the total number of tillers following the same procedure. The results were analyzed by Tukey test at 5% after transforming the data to log(x. For the first evaluation there was no statistical difference in the total number of tillers between cultivars. But, in the second evaluation, the total number of tillers of NO 78

The intermediate disturbance hypothesis applies to tropical forests, but disturbance contributes little to tree diversity.

Science.gov (United States)

Bongers, Frans; Poorter, Lourens; Hawthorne, William D; Sheil, Douglas

2009-08-01

The intermediate disturbance hypothesis (IDH) predicts local species diversity to be maximal at an intermediate level of disturbance. Developed to explain species maintenance and diversity patterns in species-rich ecosystems such as tropical forests, tests of IDH in tropical forest remain scarce, small-scale and contentious. We use an unprecedented large-scale dataset (2504 one-hectare plots and 331,567 trees) to examine whether IDH explains tree diversity variation within wet, moist and dry tropical forests, and we analyse the underlying mechanism by determining responses within functional species groups. We find that disturbance explains more variation in diversity of dry than wet tropical forests. Pioneer species numbers increase with disturbance, shade-tolerant species decrease and intermediate species are indifferent. While diversity indeed peaks at intermediate disturbance levels little variation is explained outside dry forests, and disturbance is less important for species richness patterns in wet tropical rain forests than previously thought.

Surface intermediates on metal electrodes at high temperatures

DEFF Research Database (Denmark)

Zachau-Christiansen, Birgit; Jacobsen, Torben; Bay, Lasse

1998-01-01

The mechanisms widely conceived for the O(2)-reduction or H(2)-oxidation reactions in SOFC's involve intermediate O/H species adsorbed on the electrode surface. The presence of these intermediates is investigated by linear sweep voltammetry. In air at moderate temperatures (500 degrees C) Pt...

Surface Intermediates on Metal Electrodes at High Temperature

DEFF Research Database (Denmark)

Zachau-Christiansen, Birgit; Jacobsen, Torben; Bay, Lasse

1997-01-01

The mechanisms widely suggested for the O2-reduc-tion or H2-oxidation SOFC reactions involve inter-mediate O/H species adsorbed on the electrode surface. The presence of these intermediates is investigated by linear sweep voltammetry. In airat moderate temperatures (500øC) Pt in contact with YSZ...

Spectroscopic studies of neutral and chemically oxidized species of β-carotene, lycopene and norbixin in CH{sub 2}Cl{sub 2}: Fluorescence from intermediate compounds

Energy Technology Data Exchange (ETDEWEB)

Alwis, D.D.D.H [Department of Chemistry, The Open University of Sri Lanka, Nawala (Sri Lanka); Department of Chemistry, University of Sri Jayewardenepura, Nugegoda (Sri Lanka); Chandrika, U.G. [Department of Biochemistry, University of Sri Jayewardenepura, Nugegoda (Sri Lanka); Jayaweera, P.M., E-mail: pradeep@sjp.ac.lk [Department of Chemistry, University of Sri Jayewardenepura, Nugegoda (Sri Lanka)

2015-02-15

Radical cations, dications and oxidized intermediate species of three carotenoids, namely, β-carotene, lycopene and norbixin, were generated in CH{sub 2}Cl{sub 2} solutions via chemical oxidation using anhydrous FeCl{sub 3}. UV–vis, fluorescence and fluorescence-excitation spectroscopic studies were performed to understand and compare the nature of intermediate species generated during the chemical oxidation process and subsequent degradation. The intense emission observed at 550 nm can be assigned to the S{sub 2}→S{sub 0} (1{sup 1}B{sub u}→1{sup 1}A{sub g}) transition of the carotenoid molecules. The 350 nm excitation during the oxidation process for β-carotene, lycopene and norbixin exhibit intense fluorescence peaks at 492 nm, 493 nm and 500 nm, respectively. These peaks are assigned to intermediate peroxy/epoxy compounds of the three molecules that are formed with molecular oxygen prior to the formation of oxidized short-chain stable compounds. - Highlights: • Fluorescence and UV–vis studies on β-carotene, lycopene and norbixin. • Oxidation, induced by FeCl{sub 3} in CH{sub 2}Cl{sub 2} shows blue shifted fluorescence peaks. • Fluorescence peaks were assigned to intermediate peroxy/epoxy forms of carotenoids. • The D0→D3 transition of radical cations are observed in the near IR region.

The intermediate disturbance hypothesis applies to tropical forests, but disturbance contributes little to tree diversity

NARCIS (Netherlands)

Bongers, F.; Poorter, L.; Hawthorne, W.D.; Sheil, D.

2009-01-01

The intermediate disturbance hypothesis (IDH) predicts local species diversity to be maximal at an intermediate level of disturbance. Developed to explain species maintenance and diversity patterns in species-rich ecosystems such as tropical forests, tests of IDH in tropical forest remain scarce,

Unique photosynthetic phenotypes in Portulaca (Portulacaceae): C3-C4 intermediates and NAD-ME C4 species with Pilosoid-type Kranz anatomy.

Science.gov (United States)

Voznesenskaya, Elena V; Koteyeva, Nuria K; Edwards, Gerald E; Ocampo, Gilberto

2017-01-01

Portulacaceae is a family that has considerable diversity in photosynthetic phenotypes. It is one of 19 families of terrestrial plants where species having C 4 photosynthesis have been found. Most species in Portulaca are in the alternate-leaved (AL) lineage, which includes one clade (Cryptopetala) with taxa lacking C 4 photosynthesis and three clades having C 4 species (Oleracea, Umbraticola and Pilosa). All three species in the Cryptopetala clade lack Kranz anatomy, the leaves have C 3 -like carbon isotope composition and they have low levels of C 4 cycle enzymes. Anatomical, biochemical and physiological analyses show they are all C 3 -C 4 intermediates. They have intermediate CO 2 compensation points, enrichment of organelles in the centripetal position in bundle sheath (BS) cells, with selective localization of glycine decarboxylase in BS mitochondria. In the three C 4 clades there are differences in Kranz anatomy types and form of malic enzyme (ME) reported to function in C 4 (NAD-ME versus NADP-ME): Oleracea (Atriplicoid, NAD-ME), Umbraticola (Atriplicoid, NADP-ME) and Pilosa (Pilosoid, NADP-ME). Structural and biochemical analyses were performed on Pilosa clade representatives having Pilosoid-type leaf anatomy with Kranz tissue enclosing individual peripheral vascular bundles and water storage in the center of the leaf. In this clade, all species except P. elatior are NADP-ME-type C 4 species with grana-deficient BS chloroplasts and grana-enriched M chloroplasts. Surprisingly, P. elatior has BS chloroplasts enriched in grana and NAD-ME-type photosynthesis. The results suggest photosynthetic phenotypes were probably derived from an ancestor with NADP-ME-type C 4 , with two independent switches to NAD-ME type. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Fungic microflora of Panicum maximum and Styosanthes spp. commercial seed / Microflora fúngica de sementes comerciais de Panicum maximum e Stylosanthes spp.

Directory of Open Access Journals (Sweden)

Larissa Rodrigues Fabris

2010-09-01

Full Text Available The sanitary quality of 26 lots commercial seeds of tropical forages, produced in different regions (2004-05 and 2005-06 was analyzed. The lots were composed of seeds of Panicum maximum ('Massai', 'Mombaça' e 'Tanzânia' and stylo ('Estilosantes Campo Grande' - ECG. Additionally, seeds of two lots of P. maximum for exportation were analyzed. The blotter test was used, at 20ºC under alternating light and darkness in a 12 h photoperiod, for seven days. The Aspergillus, Cladosporium and Rhizopus genus consisted the secondary or saprophytes fungi (FSS with greatest frequency in P. maximum lots. In general, there was low incidence of these fungus in the seeds. In relation to pathogenic fungi (FP, it was detected high frequency of contaminated lots by Bipolaris, Curvularia, Fusarium and Phoma genus. Generally, there was high incidence of FP in P. maximum seeds. The occurrence of Phoma sp. was hight, because in 81% of the lots showed incidence superior to 50%. In 'ECG' seeds it was detected FSS (Aspergillus, Cladosporium, and Penicillium genus and FP (Bipolaris, Curvularia, Fusarium and Phoma genus, usually, in low incidence. FSS and FP were associated to P. maximum seeds for exportation, with significant incidence in some cases. The results indicated that there was a limiting factor in all producer regions regarding sanitary quality of the seeds.Sementes comerciais de forrageiras tropicais, pertencente a 26 lotes produzidos em diferentes regiões (safras 2004-05 e 2005-06, foram avaliadas quanto à sanidade. Foram analisadas sementes de cultivares de Panicum maximum (Massai, Mombaça e Tanzânia e de estilosantes (Estilosantes Campo Grande – ECG. Adicionalmente, avaliou-se a qualidade sanitária de dois lotes de sementes de P. maximum destinados à exportação. Para isso, as sementes foram submetidas ao teste de papel de filtro em gerbox, os quais foram incubados a 20ºC, com fotoperíodo de 12 h, durante sete dias. Os fungos saprófitos ou

Reactive intermediates in the gas phase generation and monitoring

CERN Document Server

Setser, D W

2013-01-01

Reactive Intermediates in the Gas Phase: Generation and Monitoring covers methods for reactive intermediates in the gas phase. The book discusses the generation and measurement of atom and radical concentrations in flow systems; the high temperature flow tubes, generation and measurement of refractory species; and the electronically excited long-lived states of atoms and diatomic molecules in flow systems. The text also describes the production and detection of reactive species with lasers in static systems; the production of small positive ions in a mass spectrometer; and the discharge-excite

Genetic Diversity and Population Structure of Broomcorn Millet (Panicum miliaceum L.) Cultivars and Landraces in China Based on Microsatellite Markers

Science.gov (United States)

Liu, Minxuan; Xu, Yue; He, Jihong; Zhang, Shuang; Wang, Yinyue; Lu, Ping

2016-01-01

Broomcorn millet (Panicum miliaceum L.), one of the first domesticated crops, has been grown in Northern China for at least 10,000 years. The species is presently a minor crop, and evaluation of its genetic diversity has been very limited. In this study, we analyzed the genetic diversity of 88 accessions of broomcorn millet collected from various provinces of China. Amplification with 67 simple sequence repeat (SSR) primers revealed moderate levels of diversity in the investigated accessions. A total of 179 alleles were detected, with an average of 2.7 alleles per locus. Polymorphism information content and expected heterozygosity ranged from 0.043 to 0.729 (mean = 0.376) and 0.045 to 0.771 (mean = 0.445), respectively. Cluster analysis based on the unweighted pair group method of mathematical averages separated the 88 accessions into four groups at a genetic similarity level of 0.633. A genetic structure assay indicated a close correlation between geographical regions and genetic diversity. The uncovered information will be valuable for defining gene pools and developing breeding programs for broomcorn millet. Furthermore, the millet-specific SSR markers developed in this study should serve as useful tools for assessment of genetic diversity and elucidation of population structure in broomcorn millet. PMID:26985894

Morphophysiological and chemical aspects of torpedograss (Panicum repens L., Poaceae

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Simone Meredith Scheffer-Basso

2007-09-01

Full Text Available This work evaluated some of the morphophysiological and bromatological aspects of torpedograss (Panicum repens L. through the quantification of accumulation, allocation and chemical composition of dry matter (DM during spring-summer. Four destructive harvests of aerial and underground parts were carried out on 23 October 2003, 3 December 2003, 22 January 2004 and 20 February 2004, corresponding to 31, 73, 123 and 152 days after the start of the spring. In these harvests, the DM accumulation was respectively 1,650; 4,470; 10,900 and 14,540 kg/ha in the aerial part, with leaf percentages between 45% (first harvest and 35% (last harvest. The crude protein (CP, neutral detergent fiber (NDF and acid detergent fiber (ADF changed between the first and the last harvest, from 9.9 to 7% (CP, 63.9% to 70.3% (FDN, and 37% to 40.8% (FDA, in samples composed by leaves, culms, inflorescences and stolons. The DM allocation to rhizomes (Rh, roots (R, leaves (L, culms+stolons (C and inflorescences (I changed, between the first and the last harvest, from 42 to 19% (Rh, 10 to 7% (R, 22 to 27% (L, 25 to 44% (C, and 0 to 2% (I.

DESEMPENHOS TÉCNICOS E ECONÔMICOS DA CONSORCIAÇÃO DE MILHO COM FORRAGEIRAS DOS GÊNEROS Panicum E Brachiaria EM SISTEMA DE INTEGRAÇÃO LAVOURA-PECUÁRIA TECHNICAL AND ECONOMIC PERFORMANCE OF CORN INTERCROPPED WITH Panicum AND Brachiaria FORAGE IN CROP-LIVESTOCK INTEGRATION SYSTEM

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Carlos Alessandro Chioderoli

2009-10-01

Full Text Available

O trabalho teve como objetivo analisar a produtividade de grãos e os resultados econômicos de modalidades do cultivo de milho com forrageiras dos gêneros Panicum e Brachiaria, na integração lavoura-pecuária (ILP, sob sistema plantio direto (SPD. O experimento foi conduzido no ano agrícola de 2007/2008, no município de Selvíria, MS, em Latossolo Vermelho distroférrico. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições, sendo os tratamentos constituídos por oito modalidades de cultivo do milho consorciado, simultaneamente e por ocasião da adubação nitrogenada de cobertura com os capins Tanzânia, Mombaça, Marandu e Ruziziensis, além do seu cultivo sem consórcio. A análise dos custos operacionais foi baseada nos preços de insumos e operações e a receita bruta no preço médio de venda do milho, no Estado de São Paulo. O decréscimo dos valores da relação custo/benefício e os melhores retornos econômicos, obtidos em função dos maiores índices de margem de contribuição, determinaram as modalidades de cultivo mais viáveis. Os capins Mombaça e Marandu, consorciados, simultaneamente, ao milho, reduziram a produtividade de grãos, em relação ao milho cultivado sem o consórcio. Com relação aos benefícios técnico-econômicos, visando à utilização em sistemas de ILP, o consórcio mais recomendado é o de milho com capim Tânzania, principalmente no cultivo simultâneo. No entanto, resultados técnico-econômicos a longo prazo, com diferentes preços e produtividades, devem ser avaliados

Transcriptional and physiological data reveal the dehydration memory behavior in switchgrass (Panicum virgatum L.).

Science.gov (United States)

Zhang, Chao; Peng, Xi; Guo, Xiaofeng; Tang, Gaijuan; Sun, Fengli; Liu, Shudong; Xi, Yajun

2018-01-01

Switchgrass ( Panicum virgatum L.) is a model biofuel plant because of its high biomass, cellulose-richness, easy degradation to ethanol, and the availability of extensive genomic information. However, a little is currently known about the molecular responses of switchgrass plants to dehydration stress, especially multiple dehydration stresses. Studies on the transcriptional profiles of 35-day-old tissue culture plants revealed 741 dehydration memory genes. Gene Ontology and pathway analysis showed that these genes were enriched in phenylpropanoid biosynthesis, starch and sucrose metabolism, and plant hormone signal transduction. Further analysis of specific pathways combined with physiological data suggested that switchgrass improved its dehydration resistance by changing various aspects of its responses to secondary dehydration stress (D2), including the regulation of abscisic acid (ABA) and jasmonic acid (JA) biosynthesis and signal transduction, the biosynthesis of osmolytes (l-proline, stachyose and trehalose), energy metabolism (i.e., metabolic process relating to photosynthetic systems, glycolysis, and the TCA cycle), and lignin biosynthesis. The transcriptional data and chemical substance assays showed that ABA was significantly accumulated during both primary (D1) and secondary (D2) dehydration stresses, whereas JA accumulated during D1 but became significantly less abundant during D2. This suggests the existence of a complicated signaling network of plant hormones in response to repeated dehydration stresses. A homology analysis focusing on switchgrass, maize, and Arabidopsis revealed the conservation and species-specific distribution of dehydration memory genes. The molecular responses of switchgrass plants to successive dehydration stresses have been systematically characterized, revealing a previously unknown transcriptional memory behavior. These results provide new insights into the mechanisms of dehydration stress responses in plants. The genes and

Rendimiento y calidad de semilla de pasto guinea (Panicum maximum Jacq.) cv. Tanzania usando la fitohormona esteroidal cidef-4

OpenAIRE

Bertín Maurilio Joaquín Torres; Miguel Angel Moreno Carrillo; Santiago Joaquín Cancino; Alfonso Hernández Garay; Jorge Pérez Pérez; Armando Gómez Vázquez

2010-01-01

El objetivo fue evaluar el efecto de la fitohormona esteroidal cidef-4 en el rendimiento y calidad de semilla en Panicum maximum cv. Tanzania. El experimento se realizó durante el 2001 en Tejupilco, Estado de México. Los tratamientos evaluados fueron, T1=testigo, T2=4 mg L-1 de ingrediente activo (i.a.) aplicados al inicio de antesis, T3=4 mg L-1 de i.a. aplicados antes del espigamiento e inicio de antesis, T4=8 mg L-1 de i.a. aplicados al inicio de antesis, T5=8 mg L-1 de i.a. aplicados ante...

Rendimiento y calidad de semilla de pasto guinea (Panicum maximum Jacq.) cv. Tanzania usando la fitohormona esteroidal cidef-4

OpenAIRE

Joaquín Torres, Bertin Maurilio; Moreno Carrillo, Miguel Angel; Joaquín Cancino, Santiago; Hernández Garay, Alfonso; Pérez Pérez, Jorge; Gómez Vázquez, Armando

2010-01-01

El objetivo fue evaluar el efecto de la fitohormona esteroidal cidef-4 en el rendimiento y calidad de semilla en Panicum maximum cv. Tanzania. El experimento se realizó durante el 2001 en Tejupilco, Estado de México. Los tratamientos evaluados fueron: T1=testigo; T2=4 mg L-1 de ingrediente activo (i.a.) aplicados al inicio de antesis; T3=4 mg L-1 de i.a. aplicados antes del espigamiento e inicio de antesis; T4=8 mg L-1 de i.a. aplicados al inicio de antesis; T5=8 mg L-1 de i.a. aplicados ante...

Krebs Cycle Intermediates Protective against Oxidative Stress by Modulating the Level of Reactive Oxygen Species in Neuronal HT22 Cells

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Kenta Sawa

2017-03-01

Full Text Available Krebs cycle intermediates (KCIs are reported to function as energy substrates in mitochondria and to exert antioxidants effects on the brain. The present study was designed to identify which KCIs are effective neuroprotective compounds against oxidative stress in neuronal cells. Here we found that pyruvate, oxaloacetate, and α-ketoglutarate, but not lactate, citrate, iso-citrate, succinate, fumarate, or malate, protected HT22 cells against hydrogen peroxide-mediated toxicity. These three intermediates reduced the production of hydrogen peroxide-activated reactive oxygen species, measured in terms of 2′,7′-dichlorofluorescein diacetate fluorescence. In contrast, none of the KCIs—used at 1 mM—protected against cell death induced by high concentrations of glutamate—another type of oxidative stress-induced neuronal cell death. Because these protective KCIs did not have any toxic effects (at least up to 10 mM, they have potential use for therapeutic intervention against chronic neurodegenerative diseases.

Evaluation of genetic diversity of Panicum turgidum Forssk from Saudi Arabia.

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Assaeed, Abdulaziz M; Al-Faifi, Sulieman A; Migdadi, Hussein M; El-Bana, Magdy I; Al Qarawi, Abdulaziz A; Khan, Mohammad Altaf

2018-01-01

The genetic diversity of 177 accessions of Panicum turgidum Forssk, representing ten populations collected from four geographical regions in Saudi Arabia, was analyzed using amplified fragment length polymorphism (AFLP) markers. A set of four primer-pairs with two/three selective nucleotides scored 836 AFLP amplified fragments (putative loci/genome landmarks), all of which were polymorphic. Populations collected from the southern region of the country showed the highest genetic diversity parameters, whereas those collected from the central regions showed the lowest values. Analysis of molecular variance (AMOVA) revealed that 78% of the genetic variability was attributable to differences within populations. Pairwise values for population differentiation and genetic structure were statistically significant for all variances. The UPGMA dendrogram, validated by principal coordinate analysis-grouped accessions, corresponded to the geographical origin of the accessions. Mantel's test showed that there was a significant correlation between the genetic and geographical distances ( r  = 0.35, P  < 0.04). In summary, the AFLP assay demonstrated the existence of substantial genetic variation in P. turgidum . The relationship between the genetic diversity and geographical source of P. turgidum populations of Saudi Arabia, as revealed through this comprehensive study, will enable effective resource management and restoration of new areas without compromising adaptation and genetic diversity.

Hippobosca longipennis - a potential intermediate host of a species of Acanthocheilonema in dogs in northern India

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Irwin Peter J

2011-07-01

Full Text Available Abstract Background Hippobosca longipennis (the 'dog louse fly' is a blood sucking ectoparasite found on wild carnivores such as cheetahs and lions and domesticated and feral dogs in Africa, the Middle East and Asia, including China. Known as an intermediate host for Acanthocheilonema dracunculoides and a transport host for Cheyletiella yasguri, it has also been suggested that H. longipennis may be a vector for other pathogens, including Acanthocheilonema sp.? nov., which was recently reported to infect up to 48% of dogs in northern India where this species of fly is known to commonly infest dogs. To test this hypothesis, hippoboscid flies feeding on dogs in Ladakh in northern India were collected and subjected to microscopic dissection. Results A total of 12 infective larvae were found in 10 out of 65 flies dissected; 9 from the head, 2 from the thorax and 1 from the abdomen. The larvae averaged 2, 900 (± 60 μm in length and 34 (± 5 μm in width and possessed morphological features characteristic of the family Onchocercidae. Genetic analysis and comparison of the 18S, ITS-2, 12S and cox-1 genes confirmed the identity of the larvae as the Acanthocheilonema sp.? nov. reported in dogs in Ladakh. Conclusion This study provides evidence for a potential intermediate host-parasite relationship between H. longipennis and the canine Acanthocheilonema sp.? nov. in northern India.

Variable mycorrhizal benefits on the reproductive output of Geranium sylvaticum, with special emphasis on the intermediate phenotype.

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Varga, S; Kytöviita, M-M

2014-03-01

In several gynodioecious species, intermediate sex between female and hermaphrodite has been reported, but few studies have investigated fitness parameters of this intermediate phenotype. Here, we examined the interactions between plant sex and arbuscular mycorrhizal (AM) fungal species affecting the reproductive output of Geranium sylvaticum, a sexually polymorphic plant species with frequent intermediate sexes between females and hermaphrodites, using a common garden experiment. Flowering phenology, AM colonisation levels and several plant vegetative and reproductive parameters, including seed and pollen production, were measured. Differences among sexes were detected in flowering, fruit set, pollen production and floral size. The two AM species used in the present work had different effects on plant fitness parameters. One AM species increased female fitness through increasing seed number and seed mass, while the other species reduced seed mass in all sexes investigated. AM fungi did not affect intermediate and hermaphrodite pollen content in anthers. The three sexes in G. sylvaticum did not differ in their reproductive output in terms of total seed production, but hermaphrodites had potentially larger fathering ability than intermediates due to higher anther number. The ultimate female function--seed production--did not differ among the sexes, but one of the AM fungi used potentially decreased host plant fitness. In addition, in the intermediate sex, mycorrhizal symbiosis functioned similarly in females as in hermaphrodites. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

Consumo voluntário de forragem de três cultivares de Panicum maximum sob pastejo Voluntary intake of three cultivars of Panicum maximum under grazing

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Valéria Pacheco Batista Euclides

1999-01-01

Full Text Available Os objetivos deste trabalho foram estimar o consumo de matéria seca de animais pastejando três cultivares de Panicum maximum e relacioná-lo com ganho de peso, tempo de pastejo (TP e algumas características químicas e estruturais do pasto. O delineamento experimental foi o de blocos casualizados com três tratamentos e três repetições. O consumo voluntário de matéria seca (CVMS foi estimado em quatro ocasiões (maio, setembro, novembro e fevereiro. Para calcular a produção de fezes, foi usado o óxido crômico como marcador externo. Foram estimados a digestibilidade in situ da matéria seca e o tempo de pastejo, respectivamente, por intermédio de extrusas e tacógrafos. Foram estimadas as disponibilidades da forragem e dos componentes da planta. Apesar de os CVMS pelos animais terem sido semelhantes entre as cultivares, foram observadas maiores diferenças nos ganhos de peso, para os animais pastejando o capim Tanzânia, seguidos daqueles pastejando os capins Colonião e Tobiatã. Diferenças também foram observadas entre as cultivares para TP, que foi menor para os animais em pasto de Tobiatã, quando comparados aos que pastejaram as outras duas cultivares. O aumento no TP observado durante o período da seca não foi suficiente para impedir queda no consumo de forragem neste período. O CVMS foi correlacionado (r² = 0,77 com ganho diário de peso. As características estruturais das pastagens, disponibilidade de folhas e relação material verde:material morto, influenciaram mais o CVMS, ganho de peso diário e TP que os valores nutritivos das mesmas.The objectives of this work were to estimate the dry matter intake by animals grazing three cultivars of Panicum maximum, and to relate it to live weight gain, grazing time (GT and some structural and chemical characteristics of the pastures. The experimental design was the randomized block with three treatments and three replicates. The dry matter voluntary intake (DMVI was

The functional significance of C3-C4 intermediate traits in Heliotropium L. (Boraginaceae): gas exchange perspectives.

Science.gov (United States)

Vogan, Patrick J; Frohlich, Michael W; Sage, Rowan F

2007-10-01

We demonstrate for the first time the presence of species exhibiting C3-C4 intermediacy in Heliotropium (sensu lato), a genus with over 100 C3 and 150 C4 species. CO2 compensation points (Gamma) and photosynthetic water-use efficiencies (WUEs) were intermediate between C3 and C4 values in three species of Heliotropium: Heliotropium convolvulaceum (Gamma = 20 micromol CO2 mol(-1) air), Heliotropium racemosum (Gamma = 22 micromol mol(-1)) and Heliotropium greggii (Gamma = 17 micromol mol(-1)). Heliotropium procumbens may also be a weak C3-C4 intermediate based on a slight reduction in Gamma (48.5 micromol CO2 mol(-1)) compared to C3Heliotropium species (52-60 micromol mol(-1)). The intermediate species H. convolvulaceum, H. greggii and H. racemosum exhibited over 50% enhancement of net CO2 assimilation rates at low CO2 levels (200-300 micromol mol(-1)); however, no significant differences in stomatal conductance were observed between the C3 and C3-C4 species. We also assessed the response of Gamma to variation in O2 concentration for these species. Heliotropium convolvulaceum, H. greggii and H. racemosum exhibited similar responses of Gamma to O2 with response slopes that were intermediate between the responses of C3 and C4 species below 210 mmol O2 mol(-1) air. The presence of multiple species displaying C3-C4 intermediate traits indicates that Heliotropium could be a valuable new model for studying the evolutionary transition from C3 to C4 photosynthesis.

The suitability of several aquatic snails as intermediate hosts for Angiostrongylus cantonensis.

Science.gov (United States)

Yousif, F; Lämmler, G

1975-10-16

Sixteen species of aquatic snails of four families were tested by quantitative technique under standardized conditions for their suitability as intermediate hosts for Angiostrongylus cantonensis. These species were the planorbid snails Biomphalaria glabrata, Biomphalaria alexandrina, Planorbis planorbis, Planorbis intermixtus, Bulinus truncatus, Bulinus contortus, Bulinus africanus, Bulinus tropicus and Helisoma sp.; the lymnaeid snails Lymnaea natalensis, Lymnaea tomentosa, Lymnaea stagnalis, and Stagnicola elodes; the physid snail Physa acuta (an Egyptian and a German strain) and the ampullariid snails Marisa cornuarietis and Lanistes carinatus. All these snail species proved to be susceptible to infection with A. cantonensis, and first stage larvae reached the infective third stage in all of them. However, the rate and intensity of infection varied with different species. B. glabrata was the most susceptible snail species with a 100% infection rate and an average percentage recovery of third stage larvae of 26.1. This was followed by S. elodes and B. africanus, with a 100% infection rate and an average percentage recovery of third stage larvae of 15.6 and 14.6 respectively. The rest of snail species proved to be less susceptible. For comparative evaluation of the suitability of the various snail species as intermediate hosts of A. cantonensis a "Capacity Index" was determined. This index should provide a useful method for the evaluation of the suitability of various snails as intermediate hosts of nematode parasites under standardized conditions in the laboratory.

Descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham: I. Influencia de su composición química Litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham: I. Influence of their chemical composition

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Saray Sánchez

2009-09-01

Full Text Available Con el objetivo de determinar la descomposición de la hojarasca y su relación con la composición química de Panicum maximum y Leucaena leucocephala en un sistema silvopastoril, se realizó este experimento en la EEPF "Indio Hatuey". La descomposición de la hojarasca se determinó como la pérdida de biomasa a través del tiempo, con relación al peso inicial. Para el estudio de la dinámica de la descomposición se utilizó el método de bolsas de hojarasca (litter bags. En cada especie se presentó un patrón diferente de descomposición de la hojarasca; la tasa promedio de descomposición de la hojarasca en leucaena fue mayor que en la guinea. En ambas especies se encontró una rápida pérdida de peso durante los primeros 30 días y después el proceso fue más lento. Este comportamiento puede estar relacionado con la composición química de los pastos, pues el porcentaje de biomasa perdida de la hojarasca de L. leucocephala presentó una mayor correlación con las concentraciones del contenido celular, la relación lignina/nitrógeno, la celulosa y el Nt. Se observó una dependencia significativa y negativa de la hojarasca de P. maximum con las concentraciones de la FND y la hemicelulosa; mientras que se relacionó de forma positiva con las de N-FND y la relación lignina/nitrógenoWith the objective of determining the litter decomposition and its relationship to the chemical composition of Panicum maximum and Leucaena leucocephala in a silvopastoral system, this trial was conducted at the EEPF «Indio Hatuey». Litter decomposition was determined as biomass loss through time, with regards to initial weight. For studying the decomposition dynamics, the method of litter bags was used. In each species a different litter decomposition pattern appeared; the average litter decomposition rate was higher in leucaena than in Guinea grass. Rapid weight loss was found in both species during the first 30 days and afterwards the process was slower

Root-Zone Glyphosate Exposure Adversely Affects Two Ditch Species

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Lyndsay E. Saunders

2013-12-01

Full Text Available Glyphosate, one of the most applied herbicides globally, has been extensively studied for its effects on non-target organisms. In the field, following precipitation, glyphosate runs off into agricultural ditches where it infiltrates into the soil and thus may encounter the roots of vegetation. These edge-of-field ditches share many characteristics with wetlands, including the ability to reduce loads of anthropogenic chemicals through uptake, transformation, and retention. Different species within the ditches may have a differential sensitivity to exposure of the root zone to glyphosate, contributing to patterns of abundance of ruderal species. The present laboratory experiment investigated whether two species commonly found in agricultural ditches in southcentral United States were affected by root zone glyphosate in a dose-dependent manner, with the objective of identifying a sublethal concentration threshold. The root zone of individuals of Polygonum hydropiperoides and Panicum hemitomon were exposed to four concentrations of glyphosate. Leaf chlorophyll content was measured, and the ratio of aboveground biomass to belowground biomass and survival were quantified. The findings from this study showed that root zone glyphosate exposure negatively affected both species including dose-dependent reductions in chlorophyll content. P. hydropiperdoides showed the greatest negative response, with decreased belowground biomass allocation and total mortality at the highest concentrations tested.

Global changes in mineral transporters in tetraploid switchgrasses (Panicum virgatum L.

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Nathan A. Palmer

2014-01-01

Full Text Available Switchgrass (Panicum virgatum L is perennial, C4 grass with great potential as a biofuel crop. An in-depth understanding of the mechanisms that control mineral uptake, distribution and remobilization will benefit sustainable production. Nutrients are mobilized from aerial portions to below-ground crowns and rhizomes as a natural accompaniment to above-ground senescence post seed-set. Mineral uptake and remobilization is dependent on transporters, however, little if any information is available about the specific transporters that are needed and how their relative expression changes over a growing season. Using well-defined classes of mineral transporters, we identified 520 genes belonging to 40 different transporter classes in the tetraploid switchgrass genome. Expression patterns were determined for many of these genes using publically available transcriptomic datasets obtained from both greenhouse and field grown plants. Certain transporters showed strong temporal patterns of expression in distinct developmental stages of the plant. Gene-expression was verified for selected transporters using qRT-PCR. By and large these analyses confirmed the developmental stage-specific expression of these genes. Mineral analyses indicated that K, Fe, Mg, Co and As had a similar pattern of accumulation with apparent limited remobilization at the end of the growing season. These initial analyses will serve as a foundation for more detailed examination of the nutrient biology of switchgrass.

Enolonium Species-Umpoled Enolates

DEFF Research Database (Denmark)

Arava, Shlomy; Kumar, Jayprakash N.; Maksymenko, Shimon

2017-01-01

Enolonium species/iodo(III) enolates of carbonyl compounds have been suggested to be intermediates in a wide variety of hypervalent iodine induced chemical transformations of ketones, including α-C-O, α-C-N, α-C-C, and alpha-carbon- halide bond formation, but they have never been characterized. We...... report that these elusive umpoled enolates may be made as discrete species that are stable for several minutes at-78 degrees C, and report the first spectroscopic identification of such species. It is shown that enolonium species are direct intermediates in C-O, C-N, C-Cl, and C-C bond forming reactions....... Our results open up chemical space for designing a variety of new transformations. We showcase the ability of enolonium species to react with prenyl, crotyl, cinnamyl, and allyl silanes with absolute regioselectivity in up to 92% yield....

The MHD intermediate shock interaction with an intermediate wave: Are intermediate shocks physical?

International Nuclear Information System (INIS)

Wu, C.C.

1988-01-01

Contrary to the usual belief that MHD intermediate shocks are extraneous, the authors have recently shown by numerical solutions of dissipative MHD equations that intermediate shocks are admissible and can be formed through nonlinear steepening from a continuous wave. In this paper, he clarifies the differences between the conventional view and the results by studying the interaction of an MHD intermediate shock with an intermediate wave. The study reaffirms his results. In addition, the study shows that there exists a larger class of shocklike solutions in the time-dependent dissiaptive MHD equations than are given by the MHD Rankine-Hugoniot relations. it also suggests a mechanism for forming rotational discontinuities through the interaction of an intermediate shock with an intermediate wave. The results are of importance not only to the MHD shock theory but also to studies such as magnetic field reconnection models

Identification and Spectroscopic Characterization of Nonheme Iron(III) Hypochlorite Intermediates**

Science.gov (United States)

Draksharapu, Apparao; Angelone, Davide; Quesne, Matthew G; Padamati, Sandeep K; Gómez, Laura; Hage, Ronald; Costas, Miquel; Browne, Wesley R; de Visser, Sam P

2015-01-01

FeIII–hypohalite complexes have been implicated in a wide range of important enzyme-catalyzed halogenation reactions including the biosynthesis of natural products and antibiotics and post-translational modification of proteins. The absence of spectroscopic data on such species precludes their identification. Herein, we report the generation and spectroscopic characterization of nonheme FeIII–hypohalite intermediates of possible relevance to iron halogenases. We show that FeIII-OCl polypyridylamine complexes can be sufficiently stable at room temperature to be characterized by UV/Vis absorption, resonance Raman and EPR spectroscopies, and cryo-ESIMS. DFT methods rationalize the pathways to the formation of the FeIII-OCl, and ultimately FeIV=O, species and provide indirect evidence for a short-lived FeII-OCl intermediate. The species observed and the pathways involved offer insight into and, importantly, a spectroscopic database for the investigation of iron halogenases. PMID:25663379

Reactions and reaction intermediates on iron surfaces--1. Methanol, ethanol, and isopropanol on Fe(100). 2. Hydrocarbons and carboxylic acids

Energy Technology Data Exchange (ETDEWEB)

Benziger, J.B.; Madix, R.J.

1980-09-01

Temperature-programed desorption and ESCA showed that the alcohols formed alkoxy intermediates on Fe(100) surfaces at room temperature, but that the methoxy and ethoxy species were much more stable than the isopropoxy intermediate. The alkoxy species reacted above 400/sup 0/K by decomposing into carbon monoxide and hydrogen, hydrogenation to alcohol, and scission of C-C and C-O bonds with hydrogenation of the hydrocarbon fragments. Ethylene, acetylene, and cis-2-butene formed stable, unidentified surface species. Methyl chloride formed stable surface methyl groups which decomposed into hydrogen and surface carbide at 475/sup 0/K. Formic and acetic acids yielded stable carboxylate intermediates which decomposed above 490/sup 0/K to hydrogen, carbon monoxide, and carbon dioxide. The studies suggested that the alkoxy surface species may be important intermediates in the Fischer-Tropsch reaction on iron.

The species in primatology.

Science.gov (United States)

Groves, Colin

2014-01-01

Biologists of the late eighteenth and early nineteenth centuries all bandied about the term "species," but very rarely actually said what they meant by it. Often, however, one can get inside their thinking by piecing together some of their remarks. One of the most nearly explicit-appropriately, for the man who wrote a book called The Origin of Species - was Charles Darwin: "Practically, when a naturalist can unite two forms together by others having intermediate characters, he treats the one as a variety of the other… He later translated this into evolutionary terms: "Hereafter, we shall be compelled to acknowledge that the only distinction between species and well-marked varieties is, that the latter are known, or believed, to be connected at the present day by intermediate gradations, whereas species were formerly thus connected"(1:484-5.) Copyright © 2014 Wiley Periodicals, Inc.

Producción de semilla de guinea (Panicum maximum Jacq. en un sistema intensivo de ceba de ganado vacuno Seed production of Guinea grass (Panicum maximum Jacq. in an intensive cattle fattening system

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G Oquend

2008-09-01

Full Text Available En un suelo Pardo sialítico del subtipo Cambisol cálcico, localizado en la Empresa Pecuaria «Calixto García», en la provincia de Holguín, se estudio la producción de semilla de guinea (Panicum maximum Jacq. en un sistema intensivo de ceba de ganado vacuno, en condiciones de riego. Los tratamientos fueron cinco varieda­des del pasto guinea: A Común; B Likoni; C Mombasa; D Tanzania; y E Tobiatá. Los siguientes métodos se consideraron a su vez como subtratamientos: 1 Siembra con semilla gámica; 2 Plantación por macollas; y 3 Por vía de trasplante. La carga se mantuvo ajustada a 2 UGM/ha. En la producción de semillas existieron interacciones favorables entre los métodos de siembra y las variedades: semilla gámica-guinea Likoni; maco­lla-guinea Mombasa, Tanzania y Tobiatá; trasplante-guinea Común. En todo el sistema de explotación se obtuvo un aporte adicional superior a los $1 000/ha por concepto de producción de semilla, sin afectar la producción animal, en la que se obtuvieron ganancias superiores a los 800 g/animal/día y producciones pro­medio de 46 212 t de carne en pie por ciclo de ceba. Se considera factible la producción de semilla del pasto guinea en sistemas intensivos de ceba de ganado vacuno.On a sialitic Brown soil of the calcic Cambisol subtype, located at the «Calixto García» Livestock Production Enterprise, in the Holguín province, the production of Guinea grass (Panicum maximum Jacq. was studied in an intensive cattle fattening system, with irrigation. The treatments were five varieties of Guinea grass: A Common; B Likoni; C Mombasa; D Tanzania; and E Tobiatá. The following methods were considered, in turn, sub-treatments: 1 Seeding with gamic seed; 2 Planting with tillers; and 3 Transplanting. The stocking rate remained adjusted at 2 animals/ha. In seed production there were favorable interactions between the planting methods and the varieties: gamic seed-Guinea grass Likoni; tiller-Guinea grass

Trapping and Characterization of a Reaction Intermediate in Carbapenem Hydrolysis by B. cereus Metallo-β-lactamase

Science.gov (United States)

Tioni, Mariana F.; Llarrull, Leticia I.; Poeylaut-Palena, Andrés A.; Martí, Marcelo A.; Saggu, Miguel; Periyannan, Gopal R.; Mata, Ernesto G.; Bennett, Brian; Murgida, Daniel H.; Vila, Alejandro J.

2009-01-01

Metallo-β-lactamases hydrolyze most β-lactam antibiotics. The lack of a successful inhibitor for them is related to the previous failure to characterize a reaction intermediate with a clinically useful substrate. Stopped-flow experiments together with rapid freeze-quench EPR and Raman spectroscopies were used to characterize the reaction of Co(II)-BcII with imipenem. These studies show that Co(II)-BcII is able to hydrolyze imipenem both in the mono- and dinuclear forms. In contrast to the situation met for penicillin, the species that accumulates during turnover is an enzyme-intermediate adduct in which the β-lactam bond has already been cleaved. This intermediate is a metal-bound anionic species, with a novel resonant structure, that is stabilized by the metal ion at the DCH or Zn2 site. This species has been characterized based on its spectroscopic features. This represents a novel, previously unforeseen intermediate, that is related to the chemical nature of carbapenems, as confirmed by the finding of a similar intermediate for meropenem. Since carbapenems are the only substrates cleaved by B1, B2 and B3 lactamases, the identification of this intermediate could be exploited as a first step towards the design of transition state based inhibitors for all three classes of metallo-β-lactamases. PMID:18980308

Genetic diversity and phylogeography of broomcorn millet (Panicum miliaceum L.) across Eurasia

Science.gov (United States)

Hunt, Harriet V; Campana, Michael G; Lawes, Matthew C; Park, Yong-Jin; Bower, Mim A; Howe, Christopher J; Jones, Martin K

2011-01-01

Broomcorn millet (Panicum miliaceum L.) is one of the world's oldest cultivated cereals, with several lines of recent evidence indicating that it was grown in northern China from at least 10 000 cal bp. Additionally, a cluster of archaeobotanical records of P. miliaceum dated to at least 7000 cal bp exists in eastern Europe. These two centres of early records could either represent independent domestications or cross-continental movement of this cereal that would predate that of any other crop by some 2 millennia. Here, we analysed genetic diversity among 98 landrace accessions from across Eurasia using 16 microsatellite loci, to explore phylogeographic structure in the Old World range of this historically important crop. The major genetic split in the data divided the accessions into an eastern and a western grouping with an approximate boundary in northwestern China. A substantial number of accessions belonging to the ‘western’ genetic group were also found in northeastern China. Further resolution subdivided the western and eastern genepools into 2 and 4 clusters respectively, each showing clear geographic patterning. The genetic data are consistent with both the single and multiple domestication centre hypotheses and add specific detail to what these hypotheses would entail regarding the spread of broomcorn millet. Discrepancies exist between the predictions from the genetic data and the current archaeobotanical record, highlighting priorities for investigation into early farming in Central Asia. PMID:22004244

Etude comparative de la digestibilité in vivo de l'herbe de guinée (Panicum maximum Jacq.) associée aux feuilles et tiges de patate douce (Ipomoea batatas (L.) Lam) (régime Panipo) ou à l'herbe de lait (Euphorbia heterophylla L.) (régime Paneuph) chez le lapin (Oryctolagus cuniculus L.) et le cobaye (Cavia porcellus L.)

OpenAIRE

Kouakou, NGDV.; Kouba, M.; Thys, E.

2016-01-01

Digestibility of Guinea grass (Panicum maximum Jacq.) associated with sweet potato leaves and stems (Ipomoea batatas (L.) Lam) (Panipo diet) or poison milk (Euphorbia heterophylla L.) (Paneuph diet) in Rabbits (Oryctolagus cuniculus L.) and in Guinea Pigs (Cavia porcellus L.). A comparative study of in vivo digestibility of Guinea grass (Panicum maximum Jacq.) associated with sweet potato leaves and stems (Ipomoea batatas (L.) Lam) (Panipo diet) or with poison milk (Euphorbia heterophylla L.)...

Unimodal tree size distributions possibly result from relatively strong conservatism in intermediate size classes.

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Yue Bin

Full Text Available Tree size distributions have long been of interest to ecologists and foresters because they reflect fundamental demographic processes. Previous studies have assumed that size distributions are often associated with population trends or with the degree of shade tolerance. We tested these associations for 31 tree species in a 20 ha plot in a Dinghushan south subtropical forest in China. These species varied widely in growth form and shade-tolerance. We used 2005 and 2010 census data from that plot. We found that 23 species had reversed J shaped size distributions, and eight species had unimodal size distributions in 2005. On average, modal species had lower recruitment rates than reversed J species, while showing no significant difference in mortality rates, per capita population growth rates or shade-tolerance. We compared the observed size distributions with the equilibrium distributions projected from observed size-dependent growth and mortality. We found that observed distributions generally had the same shape as predicted equilibrium distributions in both unimodal and reversed J species, but there were statistically significant, important quantitative differences between observed and projected equilibrium size distributions in most species, suggesting that these populations are not at equilibrium and that this forest is changing over time. Almost all modal species had U-shaped size-dependent mortality and/or growth functions, with turning points of both mortality and growth at intermediate size classes close to the peak in the size distribution. These results show that modal size distributions do not necessarily indicate either population decline or shade-intolerance. Instead, the modal species in our study were characterized by a life history strategy of relatively strong conservatism in an intermediate size class, leading to very low growth and mortality in that size class, and thus to a peak in the size distribution at intermediate sizes.

De novo transcriptome assembly for the tropical grass Panicum maximum Jacq.

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Guilherme Toledo-Silva

Full Text Available Guinea grass (Panicum maximum Jacq. is a tropical African grass often used to feed beef cattle, which is an important economic activity in Brazil. Brazil is the leader in global meat exportation because of its exclusively pasture-raised bovine herds. Guinea grass also has potential uses in bioenergy production due to its elevated biomass generation through the C4 photosynthesis pathway. We generated approximately 13 Gb of data from Illumina sequencing of P. maximum leaves. Four different genotypes were sequenced, and the combined reads were assembled de novo into 38,192 unigenes and annotated; approximately 63% of the unigenes had homology to other proteins in the NCBI non-redundant protein database. Functional classification through COG (Clusters of Orthologous Groups, GO (Gene Ontology and KEGG (Kyoto Encyclopedia of Genes and Genomes analyses showed that the unigenes from Guinea grass leaves are involved in a wide range of biological processes and metabolic pathways, including C4 photosynthesis and lignocellulose generation, which are important for cattle grazing and bioenergy production. The most abundant transcripts were involved in carbon fixation, photosynthesis, RNA translation and heavy metal cellular homeostasis. Finally, we identified a number of potential molecular markers, including 5,035 microsatellites (SSRs and 346,456 single nucleotide polymorphisms (SNPs. To the best of our knowledge, this is the first study to characterize the complete leaf transcriptome of P. maximum using high-throughput sequencing. The biological information provided here will aid in gene expression studies and marker-assisted selection-based breeding research in tropical grasses.

Comparative cytogenetic studies of Bufo ictericus, B. paracnemis (Amphibia, Anura and an intermediate form in sympatry

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Azevedo MFC

2003-01-01

Full Text Available Specimens of Bufo ictericus, Bufo paracnemis and a third type, considered an intermediate subgroup between these species, were cytogenetically studied by conventional Giemsa staining, C-banding and staining of the nucleolus organizer region (NOR. The nuclear DNA content and seroproteins were also analyzed to characterize these species, and verify the possibility of hybridization between them. Karyotypes and cytogenetic markers were essentially equal on the basis of the methods used. The DNA nuclear content found was 6.25 ± 0.30 pg/DNA in Bufo ictericus; 7.57 ± 0.40 pg/DNA in Bufo paracnemis and 7.04 ± 0.29 pg/DNA in the intermediate subgroup. Eletrophoresis of total blood serum in Bufo ictericus, Bufo paracnemis and the intermediate specimens revealed a remarkable difference in the patterns of the protein bands whose molecular weight corresponded to that of albumin. While the parental species presented two different bands, the intermediate form presented 4. However, only three of these bands were seen in each specimen. The results obtained pointed to a high probability for natural hybridization between Bufo ictericus and Bufo paracnemis in the site and specimens studied.

Intermediate-field transport of contaminants

International Nuclear Information System (INIS)

Ahn, J.; Kim, C.L.; Chambre, P.L.; Pigford, T.H.; Lee, W.W.L.

1989-06-01

This report is about ''intermediate-field'' transport or the migration of contaminants from arrays of discrete waste packages or sources. In constructing nuclear waste repositories in rock, it may be necessary to place a waste package across a rock fracture, or a rock fracture may develop some time after waste packages have been emplaced. To predict the spatial and temporal distribution of contaminant species from a line of waste packages facing a rock fracture may be important, because such fractures may now be considered a preferential pathway for released radionuclides to re-enter the biosphere. In land disposal of hazardous wastes, individual barrels may contain especially toxic material whose dispersion special attention. We have published analytic solutions for the multidimensional advective transport of contaminants from arrays of waste packages and multiple areal sources into a planar fracture. The results show a near region in which the concentrations vary greatly in the direction transverse to ground-water flow, an intermediate region in which the array can be treated as an infinite plane source of dissolving species, and a far-field region in which the array can be treated as a plane source of finite extent. The array equations have been developed for both porous and fractured media. In this paper we summarize and compare the work with multiple areal sources facing a planar fracture and an array of point sources in porous media. 5 refs., 5 figs

Switchgrass (Panicum virgatum Intercropping within Managed Loblolly Pine (Pinus taeda Does Not Affect Wild Bee Communities

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Joshua W. Campbell

2016-11-01

Full Text Available Intensively-managed pine (Pinus spp. have been shown to support diverse vertebrate communities, but their ability to support invertebrate communities, such as wild bees, has not been well-studied. Recently, researchers have examined intercropping switchgrass (Panicum virgatum, a native perennial, within intensively managed loblolly pine (P. taeda plantations as a potential source for cellulosic biofuels. To better understand potential effects of intercropping on bee communities, we investigated visitation of bees within three replicates of four treatments of loblolly pine in Mississippi, U.S.A.: 3–4 year old pine plantations and 9–10 year old pine plantations with and without intercropped switchgrass. We used colored pan traps to capture bees during the growing seasons of 2013 and 2014. We captured 2507 bees comprised of 18 different genera during the two-year study, with Lasioglossum and Ceratina being the most common genera captured. Overall, bee abundances were dependent on plantation age and not presence of intercropping. Our data suggests that switchgrass does not negatively impact or promote bee communities within intensively-managed loblolly pine plantations.

Switchgrass (Panicum virgatum) Intercropping within Managed Loblolly Pine (Pinus taeda) Does Not Affect Wild Bee Communities.

Science.gov (United States)

Campbell, Joshua W; Miller, Darren A; Martin, James A

2016-11-04

Intensively-managed pine ( Pinus spp.) have been shown to support diverse vertebrate communities, but their ability to support invertebrate communities, such as wild bees, has not been well-studied. Recently, researchers have examined intercropping switchgrass ( Panicum virgatum ), a native perennial, within intensively managed loblolly pine ( P. taeda ) plantations as a potential source for cellulosic biofuels. To better understand potential effects of intercropping on bee communities, we investigated visitation of bees within three replicates of four treatments of loblolly pine in Mississippi, U.S.A.: 3-4 year old pine plantations and 9-10 year old pine plantations with and without intercropped switchgrass. We used colored pan traps to capture bees during the growing seasons of 2013 and 2014. We captured 2507 bees comprised of 18 different genera during the two-year study, with Lasioglossum and Ceratina being the most common genera captured. Overall, bee abundances were dependent on plantation age and not presence of intercropping. Our data suggests that switchgrass does not negatively impact or promote bee communities within intensively-managed loblolly pine plantations.

Production of ethanol from lepthochloa fusca L. (kallar grass) and panicum maximum using cellulases from trichoderma SSP and cultures of saccharomyces carlsbergensis

International Nuclear Information System (INIS)

Rajoka, M.I.; Malik, K.A.

1991-01-01

Saline sodic soils have been used for production of biomass using salt tolerant grass, kallar grass followed by lesser tolerant plants, namely, sasbania aculeata or Panicum maximum or to provide biomass throughout the year for it utilization for microbial conversion. These substrates have been utilized to produce single cell protein and cellases or hemicellulases. The enzyme titer obtained after growth of cellulomonas biazotea on kallar grass could saccharify wheat straw ad bagasse for subsequent conversion to ethanol but kallar grass itself was saccharified to lesser extent, however, enzyme titres from different fungi could saccherify the biomass produced on saline lands to monomeric sugars. In these studies, the enzyme titre from Trichoderma spp. were used for saccharification purpose. (author)

Detecting Elusive Intermediates in Carbohydrate Conversion: A Dynamic Ensemble of Acyclic Glucose-Catalyst Complexes

DEFF Research Database (Denmark)

Meier, Sebastian; Karlsson, Magnus; Jensen, Pernille Rose

2017-01-01

within few seconds prior to reaching a steady state. Exchange between the acyclic intermediates increases at conditions that favor epimerization. Species accounting for less than 0.05% of total glucose can be monitored with sub-second time resolution to allow kinetic analysis of intermediate formation...... and catalytic conversion. Epimerization occurs 2-3 orders of magnitude-fold faster than the binding of acyclic glucose to the catalyst at near-optimum reaction conditions. The current study brings insight in to the nature of acyclic intermediate-catalyst complexes of very low population and into experimental...... strategies for characterizing very minor intermediates in carbohydrate conversion to value-added compounds....

Forage yield and nutritive value of Panicum maximum genotypes in the Brazilian savannah

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Francisco Duarte Fernandes

2014-02-01

Full Text Available The narrow genetic variability of grasslands and the incidence of new biotic and abiotic stresses have motivated the selection of new Panicum maximum genotypes for use as forage for beef cattle in the Brazilian savannah. This study aimed to evaluate forage yield and nutritive value of P. maximum genotypes including 14 accessions (PM30 to PM43, four intraspecific hybrids (PM44 to PM47 and six cultivars (Aruana, Massai, Milênio, Mombaça, Tanzania and Vencedor, examining 24 genotypes over two years (2003 and 2004. Milênio cultivar was the genotype with the highest dry matter yield (DMY in both years (18.4 t ha-1 and 20.9 t ha-1, respectively although it presented a high proportion of stems (~ 30%. Genotypes that showed higher Leaf DMY in both years were the accession PM34 (14.7 t ha-1 and the hybrid PM46 (14.0 t ha-1, while Mombaça and Tanzania yielded 12.5 and 11.0 t ha-1, respectively. Leaf organic matter digestibility and leaf DMY for PM40 and PM46 genotypes exceeded the mean (> 656 g kg-1 and > 11.7 t ha-1, respectively. For this reason, PM40 and PM46 can be considered promising P. maximum genotypes for use as forage for grazing systems in the Brazilian savannah.

Cryo-EM structures of two bovine adenovirus type 3 intermediates

International Nuclear Information System (INIS)

Cheng, Lingpeng; Huang, Xiaoxing; Li, Xiaomin; Xiong, Wei; Sun, Wei; Yang, Chongwen; Zhang, Kai; Wang, Ying; Liu, Hongrong; Huang, Xiaojun; Ji, Gang; Sun, Fei; Zheng, Congyi; Zhu, Ping

2014-01-01

Adenoviruses (Ads) infect hosts from all vertebrate species and have been investigated as vaccine vectors. We report here near-atomic structures of two bovine Ad type 3 (BAd3) intermediates obtained by cryo-electron microscopy. A comparison between the two intermediate structures reveals that the differences are localized in the fivefold vertex region, while their facet structures are identical. The overall facet structure of BAd3 exhibits a similar structure to human Ads; however, BAd3 protein IX has a unique conformation. Mass spectrometry and cryo-electron tomography analyses indicate that one intermediate structure represents the stage during DNA encapsidation, whilst the other intermediate structure represents a later stage. These results also suggest that cleavage of precursor protein VI occurs during, rather than after, the DNA encapsidation process. Overall, our results provide insights into the mechanism of Ad assembly, and allow the first structural comparison between human and nonhuman Ads at backbone level. - Highlights: • First structure of bovine adenovirus type 3. • Some channels are located at the vertex of intermediate during DNA encapsidation. • Protein IX exhibits a unique conformation of trimeric coiled–coiled structure. • Cleavage of precursor protein VI occurs during the DNA encapsidation process

Cryo-EM structures of two bovine adenovirus type 3 intermediates

Energy Technology Data Exchange (ETDEWEB)

Cheng, Lingpeng; Huang, Xiaoxing; Li, Xiaomin [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Xiong, Wei [State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Luo-jia-shan, Wuhan, Hubei 430072 (China); Sun, Wei; Yang, Chongwen; Zhang, Kai; Wang, Ying [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Liu, Hongrong [College of Physics and Information Science, Hunan Normal University, Changsha, Hunan 410081 (China); Huang, Xiaojun; Ji, Gang; Sun, Fei [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Zheng, Congyi, E-mail: cctcc202@whu.edu.cn [State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Luo-jia-shan, Wuhan, Hubei 430072 (China); Zhu, Ping, E-mail: zhup@ibp.ac.cn [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China)

2014-02-15

Adenoviruses (Ads) infect hosts from all vertebrate species and have been investigated as vaccine vectors. We report here near-atomic structures of two bovine Ad type 3 (BAd3) intermediates obtained by cryo-electron microscopy. A comparison between the two intermediate structures reveals that the differences are localized in the fivefold vertex region, while their facet structures are identical. The overall facet structure of BAd3 exhibits a similar structure to human Ads; however, BAd3 protein IX has a unique conformation. Mass spectrometry and cryo-electron tomography analyses indicate that one intermediate structure represents the stage during DNA encapsidation, whilst the other intermediate structure represents a later stage. These results also suggest that cleavage of precursor protein VI occurs during, rather than after, the DNA encapsidation process. Overall, our results provide insights into the mechanism of Ad assembly, and allow the first structural comparison between human and nonhuman Ads at backbone level. - Highlights: • First structure of bovine adenovirus type 3. • Some channels are located at the vertex of intermediate during DNA encapsidation. • Protein IX exhibits a unique conformation of trimeric coiled–coiled structure. • Cleavage of precursor protein VI occurs during the DNA encapsidation process.

Approach to photocatalysis at the molecular level. Design of photocatalysts, detection of intermediate species, and reaction mechanisms

Energy Technology Data Exchange (ETDEWEB)

Anpo, Masakazu [Department of Applied Chemistry, University of Osaka Prefecture, Gakuen-cho, Sakai, Osaka (Japan)

1995-08-01

The characterization of the Cu{sup +}/ZSM-5 catalysts prepared via reduction of ion-exchanged Cu{sup 2+}/ZSM-5 samples and highly dispersed Ti-oxide catalysts anchored on Vycor glass has been undertaken by in-situ photoluminescence, EPR, XAFS (XANES and FT-EXAFS), and FT-IR spectroscopy. UV-irradiation of the Cu{sup +}/ZSM-5 catalyst in the presence of NO leads to the direct photocatalytic decomposition of NO into N{sub 2} and O{sub 2} at normal temperatures. UV-irradiation of the highly dispersed anchored Ti-oxide catalyst in the presence of CO{sub 2} and H{sub 2}O also leads to the evolution of CH{sub 4}, CO, and CH{sub 3}OH at normal temperatures. The clarification of the coordination structure of the active surface sites and the direct detection of the reaction precursors and intermediate species in these photocatalytic systems contributed significantly in characterizing the molecular scale reaction mechanisms. Based on these results, the design of highly concentrated and efficient photocatalysts has successfully been achieved by application of the sol-gel method

Review of Finger millet (Eleusine coracana (L.) Gaertn): A power house of health benefiting nutrients

OpenAIRE

Dinesh Chandra; Satish Chandra; Pallavi; A.K. Sharma

2016-01-01

The bulk of the world's millet crop is produced by India, Nigeria, Niger, Mali, Burkina Faso, Chad, and China. Finger millet (Eleusine coracana (L.) Gaertn), little millet (Panicum sumatrense Roth ex Roem. & Schult.), foxtail millet (Setaria italica (L.) P. Beauvois) and proso millet (Panicum miliaceum L.) are most commonly found species among various millet varieties. In India, finger millet occupy the largest area under cultivation among the small millets. Finger millet stands unique among ...

Proso Millet (Panicum miliaceum L.) and Its Potential for Cultivation in the Pacific Northwest, U.S.: A Review.

Science.gov (United States)

Habiyaremye, Cedric; Matanguihan, Janet B; D'Alpoim Guedes, Jade; Ganjyal, Girish M; Whiteman, Michael R; Kidwell, Kimberlee K; Murphy, Kevin M

2016-01-01

Proso millet (Panicum miliaceum L. ) is a warm season grass with a growing season of 60-100 days. It is a highly nutritious cereal grain used for human consumption, bird seed, and/or ethanol production. Unique characteristics, such as drought and heat tolerance, make proso millet a promising alternative cash crop for the Pacific Northwest (PNW) region of the United States. Development of proso millet varieties adapted to dryland farming regions of the PNW could give growers a much-needed option for diversifying their predominantly wheat-based cropping systems. In this review, the agronomic characteristics of proso millet are discussed, with emphasis on growth habits and environmental requirements, place in prevailing crop rotations in the PNW, and nutritional and health benefits. The genetics of proso millet and the genomic resources available for breeding adapted varieties are also discussed. Last, challenges and opportunities of proso millet cultivation in the PNW are explored, including the potential for entering novel and regional markets.

Uso de efluentes da carcinicultura na irrigação de Panicum maximum cvs. Tanzânia e Mombaça

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Fábio Rodrigues de Miranda

Full Text Available Resumo O trabalho objetivou avaliar as alterações químicas do solo e a produção de duas cultivares de capim Panicum maximum Jacq. (Tanzânia e Mombaça, em resposta à irrigação com o efluente da carcinicultura em águas interiores e comparar os resultados com os obtidos com a irrigação convencional, utilizando água de rio. O experimento foi realizado em uma fazenda de criação de camarão, em Russas-CE. Utilizou-se um delineamento experimental de blocos casualizados, em um esquema fatorial 2 (cultivares de capim x 2 (tipos de água utilizada na irrigação. Em quatro cortes do capim foram avaliadas as variáveis de produção: altura, produtividade de matéria seca e porcentagem de matéria seca. Os dados foram submetidos à análise de variância e ao teste de Tukey. Foram analisados, antes e após a aplicação dos tratamentos, os seguintes atributos químicos do solo: pH, condutividade elétrica do extrato saturado (CEes, porcentagem de sódio trocável (PST, matéria orgânica, P, K+, Ca2+, Mg2+ e Na+. Os dados foram submetidos ao teste de t , com nível de significância de 5%. A irrigação com o efluente da carcinicultura não aumentou nem reduziu, significativamente, a produção de matéria seca das duas cultivares de Panicum maximum, em comparação com a irrigação com a água do rio Jaguaribe. Após 14 meses de cultivo, o solo irrigado com o efluente apresentou níveis significativamente maiores (p < 0,05 de Na+, CEes e PST em relação ao solo irrigado com a água do rio Jaguaribe.

Small-angle X-ray scattering studies of metastable intermediates of beta-lactoglobulin isolated after heat-induced aggregation

DEFF Research Database (Denmark)

Carrotta, R.; Arleth, L.; Pedersen, J.S.

2003-01-01

Small-angle x-ray scattering was used for studying intermediate species, isolated after heat-induced aggregation of the A variant of bovine P-lactoglobulin. The intermediates were separated in two fractions, the heated metastable dimer and heated metastable oligomers larger than the dimer. The pa...

Crescimento e desenvolvimento do dossel de Panicum maximum cv. Mombaça Canopy growth and development of Panicum maximum "cv" Mombaça

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Emerson Alexandrino

2005-12-01

Full Text Available Em duas áreas de 1.200m² de capim Panicum maximum cv. Mombaça, acompanhou-se a evolução do perfilhamento, da biomassa, do índice de área foliar (IAF, da interceptação da radiação fotossinteticamente ativa (IRFA e da eficiência de uso da radiação (EUR no verão e outono. Para melhor compreesão do crescimento do dossel, realizou-se também análise do crescimento, estimando-se a taxa de crescimento relativo (TCR, a taxa assimilatória líquida (TAL e a razão de área foliar (RAF da gramínea. Para todas as variáveis, foram consideradas estimativas semanais, realizadas aos 7º, 14º, 21º, 28º, 35º, 42º e 49º dias de rebrotação da gramínea, após pastejo de uniformização. Utilizou-se delineamento experimental inteiramente casualizado, com quatro repetições e duas áreas experimetais: uma no verão e outra no outono. No verão e no outono, foram visualizados, respectivamente, 28 e 24 pontos, sorteados pelos tratamentos experimentais, semelhantes quanto à altura do dossel e à cobertura do solo, após intenso pastejo de uniformização. O perfilhamento da gramínea, intenso na primeira semana, decresceu nas duas semanas seguintes e praticamente cessou a partir da quarta semana. A IRFA evoluiu assintoticamente, atingindo valores de 96% em ambas as estações. O IAF apresentou o mesmo padrão de resposta, com valores de 8 e 4 no verão e no outono, respectivamente. Em ambas as estações, a biomassa evoluiu de forma quadrática com o decorrer da rebrotação. A EUR, mais alta no verão que no outono, decreceu e seus respectivos valores foram 1,76 e 0,54gMS/MJ, em razão da menor precipitação pluviométrica desse período. A eficiência de crescimento do dossel, medida pela TCR, mais alta no verão que no outono e decresceu assintoticamente durante a rebrotação, em ambos os períodos. Enquanto a TAL reduziu durante o período de rebrotação, a RAF aumentou até um ponto de máximo, tanto no verão como no outono

Densidade e qualidade dos estratos de forragem do capim Tanzânia (Panicum maximum Jacq. Cv. Tanzânia-1 manejado em diferentes alturas, sob pastejo Density bulk and quality of Tanzania grass layers (Panicum maximum Jacq.cv. Tanzania-1, at different heights in grazing

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Geraldo Tadeu dos Santos

2001-05-01

Full Text Available O objetivo do trabalho foi avaliar o efeito de diferentes alturas (24; 26; 43; 45; 52; 62; 73 e 78 cm do pasto sobre a qualidade de forragem e estrutura do perfil do capim-Tanzânia, (Panicum maximum Jacq. cv. Tanzânia – 1 (Poaceae. Foram utilizados novilhos da raça Nelore sob pastejo com carga animal variável, por meio da técnica put and take. O delineamento experimental utilizado foi inteiramente casualizado, com duas repetições. A densidade de matéria seca total (DMT aumentou com o avanço no período experimental, enquanto a densidade de matéria seca de lâminas (DML não foi influenciada pelo período e pela altura do pasto. O estrato superior da pastagem foi a porção de maior qualidade, apresentando maior DML e maior teor de PB. Os estratos inferiores apresentaram menor qualidade, devido à maior DMT e menor DML, acarretando em maiores valores de FDA e FDN e menores teores de PB. O conteúdo de minerais das lâminas foi superior aos colmos, mantendo-se inalterado com relação aos estratos da pastagem.The effect of different sward heights (24; 26; 43; 45; 52; 62; 73 and 78 cm on forage quality and profile structure Tanzania grass, Panicum maximum Jacq. cv. Tanzania – 1 (Poaceae is provided. Nelore steers were used in grazing at variable stocking rates with put and take technique. The experimental design was completely randomized, with two replications. Total dry matter bulk densitity (TDMD increased during experimental period, while the leaf blade dry matter bulk density (LDMD was not influenced by period on by sward height. The upper layers had the best quality with higher LDMD and CP levels. Lower layers had the worst quality, due the higher TDMD and lower LDMD. This fact caused higher ADF and NDF levels and lower CP levels. Leaf blade mineral content was higher than that of stem, and remained unaltered in relation to the different layers.

Development of switchgrass (Panicum virgatum) as a bioenergy feedstock in the United States

International Nuclear Information System (INIS)

McLaughlin, Samuel B.; Adams Kszos, Lynn

2005-01-01

A 10-year US Department of Energy-sponsored research program designed to evaluate and develop switchgrass (Panicum virgatum), a native perennial warm-season grass, as a dedicated energy crop is reviewed. The programmatic objectives were to identify the best varieties and management practices to optimize productivity, while developing an understanding of the basis for long-term improvement of switchgrass through breeding and sustainable production in conventional agroecosystems. This research has reduced the projected production cost of switchgrass by about 25% ($8-9 Mg -1 ) through yield increases of about 50% achieved through selection of the best regionally adapted varieties; through optimizing cutting frequency and timing; and by reducing the level (by about 40%) and timing of nitrogen fertilization. Breeding research has made further gains in productivity of switchgrass that exceed the historical rate of yield improvement of corn. Studies of soil carbon storage under switchgrass indicate significant carbon sequestration will occur in soils that will improve soil productivity and nutrient cycling and can substantially augment greenhouse gas reductions associated with substituting renewable energy for fossil energy. Collaborative research with industry has included fuel production and handling in power production, herbicide testing and licensing, release of new cultivars, and genetic modifications for chemical coproduct enhancement. Economically based life cycle analyses based on this research suggest that switchgrass produced for energy will compete favorably both as an agricultural crop and as fuel for industry

Search for C4 developmental mutants in Panicum maximum Jacq

International Nuclear Information System (INIS)

Fladung, M.

2001-01-01

Full text: Mutant plants are useful tools for studying developmental processes in defined genetic backgrounds by comparing them with their respective wild type forms. In this sense, developmental mutants or mutations involved in the establishment of certain leaf or flower specific traits are of special interest. In particular, the evolution of C 4 photosynthesis from C 3 precursors was accompanied by severe developmental changes in leaf morphology and anatomy. Our search of such mutants was followed by the idea to approach the evolution of the C 4 syndrome from a mutagenic point of view. Variants affecting normal development of the C 4 leaf anatomy may, in fact, represent possible regressive steps in C4 photosynthesis. Seeds of the C4 grass Panicum maximum Jacq. were mutagenized using ethylmethanesulfonate (EMS) and putative variants were isolated in the M2 generation by visual inspection. Main selection characteristics were whole plant, leaf morphology and pigmentation, and growth characteristics. The choice of a polyploid species for mutagenesis experiments was based on the need of detecting rare mutants, which are possibly lethal when using a diploid plant species. These variants could be of regulatory nature, affecting both morphology and physiology of C 4 photosynthesis early in leaf development. In total, nearly 100 variants were isolated and grown to maturity. Main isolated variants, which conforms to the prediction mentioned above, were as following: large interveinal space-1 and -3 (lis1, lis3), abnormal bundle sheath (abs), midribless (mbl) and variegated leaf -1 (var1). The variant lis1 was a short plant with leaves smaller than the wild type, and had a leaf lamina with a crinkly surface. Photosynthetically, lis1 indicates a clear regression from the C 4 to the C 3 photosynthesis type, which was correlated in the leaf lamina with an increase in the distance between small veins. The variant lis3 was not similar phenotypically to lis1, but it also had very

Leaf Dynamics of Panicum maximum under Future Climatic Changes.

Science.gov (United States)

Britto de Assis Prado, Carlos Henrique; Haik Guedes de Camargo-Bortolin, Lívia; Castro, Érique; Martinez, Carlos Alberto

2016-01-01

Panicum maximum Jacq. 'Mombaça' (C4) was grown in field conditions with sufficient water and nutrients to examine the effects of warming and elevated CO2 concentrations during the winter. Plants were exposed to either the ambient temperature and regular atmospheric CO2 (Control); elevated CO2 (600 ppm, eC); canopy warming (+2°C above regular canopy temperature, eT); or elevated CO2 and canopy warming (eC+eT). The temperatures and CO2 in the field were controlled by temperature free-air controlled enhancement (T-FACE) and mini free-air CO2 enrichment (miniFACE) facilities. The most green, expanding, and expanded leaves and the highest leaf appearance rate (LAR, leaves day(-1)) and leaf elongation rate (LER, cm day(-1)) were observed under eT. Leaf area and leaf biomass were higher in the eT and eC+eT treatments. The higher LER and LAR without significant differences in the number of senescent leaves could explain why tillers had higher foliage area and leaf biomass in the eT treatment. The eC treatment had the lowest LER and the fewest expanded and green leaves, similar to Control. The inhibitory effect of eC on foliage development in winter was indicated by the fewer green, expanded, and expanding leaves under eC+eT than eT. The stimulatory and inhibitory effects of the eT and eC treatments, respectively, on foliage raised and lowered, respectively, the foliar nitrogen concentration. The inhibition of foliage by eC was confirmed by the eC treatment having the lowest leaf/stem biomass ratio and by the change in leaf biomass-area relationships from linear or exponential growth to rectangular hyperbolic growth under eC. Besides, eC+eT had a synergist effect, speeding up leaf maturation. Therefore, with sufficient water and nutrients in winter, the inhibitory effect of elevated CO2 on foliage could be partially offset by elevated temperatures and relatively high P. maximum foliage production could be achieved under future climatic change.

Intermediate treatments

Science.gov (United States)

John R. Jones; Wayne D. Shepperd

1985-01-01

Intermediate treatments are those applied after a new stand is successfully established and before the final harvest. These include not only intermediate cuttings - primarily thinning - but also fertilization, irrigation, and protection of the stand from damaging agents.

Land use and vegetation cover on native symbionts and interactions with cowpea

Directory of Open Access Journals (Sweden)

Beatriz C. F. Rocha

Full Text Available ABSTRACT Arbuscular mycorrhizal fungi and rhizobia are important components of agroecosystems and they respond to human interference. The objective of this study was to investigate native communities of those microorganisms in soil collected under the native forest, four pastures (Brachiaria brizantha, Panicum maximum, Arachis pintoi and Stylosanthes guianensis and a fallow soil after maize cultivation, in interaction with cowpea (Vigna unguculata. The cowpea grew in a greenhouse until flowering. They were randomly distributed depending on soil, in five replications. The lowest mycorrhizal fungi sporulation and mycorrhizal root colonization occurred under the Panicum and forest soil. In the soils under forest and Stylosanthes, the cowpea did not exhibit nodules and grew less. Among the anthropized areas, the effect was variable, with stimulus to the multiplication and symbiosis of these microorganisms, except in areas of Panicum and Stylosanthes. When the native vegetation is substituted by pasture or farming, the mycorrhizal fungi and rhizobia proliferation predominate. However, the effect and its magnitude depends on the grown plant species, with reflects on the plant species in succession, such as the cowpea.

Trait-fitness relationships determine how trade-off shapes affect species coexistence.

Science.gov (United States)

Ehrlich, Elias; Becks, Lutz; Gaedke, Ursula

2017-12-01

Trade-offs between functional traits are ubiquitous in nature and can promote species coexistence depending on their shape. Classic theory predicts that convex trade-offs facilitate coexistence of specialized species with extreme trait values (extreme species) while concave trade-offs promote species with intermediate trait values (intermediate species). We show here that this prediction becomes insufficient when the traits translate non-linearly into fitness which frequently occurs in nature, e.g., an increasing length of spines reduces grazing losses only up to a certain threshold resulting in a saturating or sigmoid trait-fitness function. We present a novel, general approach to evaluate the effect of different trade-off shapes on species coexistence. We compare the trade-off curve to the invasion boundary of an intermediate species invading the two extreme species. At this boundary, the invasion fitness is zero. Thus, it separates trait combinations where invasion is or is not possible. The invasion boundary is calculated based on measurable trait-fitness relationships. If at least one of these relationships is not linear, the invasion boundary becomes non-linear, implying that convex and concave trade-offs not necessarily lead to different coexistence patterns. Therefore, we suggest a new ecological classification of trade-offs into extreme-favoring and intermediate-favoring which differs from a purely mathematical description of their shape. We apply our approach to a well-established model of an empirical predator-prey system with competing prey types facing a trade-off between edibility and half-saturation constant for nutrient uptake. We show that the survival of the intermediate prey depends on the convexity of the trade-off. Overall, our approach provides a general tool to make a priori predictions on the outcome of competition among species facing a common trade-off in dependence of the shape of the trade-off and the shape of the trait

Large-scale determinants of intestinal schistosomiasis and intermediate host snail distribution across Africa

DEFF Research Database (Denmark)

Stensgaard, Anna-Sofie; Utzinger, Jürg; Vounatsou, Penelope

2013-01-01

The geographical ranges of most species, including many infectious disease agents and their vectors and intermediate hosts, are assumed to be constrained by climatic tolerances, mainly temperature. It has been suggested that global warming will cause an expansion of the areas potentially suitable...... impacts of climatic changes. Snail species distribution models included several combinations of climatic and habitat-related predictors; the latter divided into "natural" and "human-impacted" habitat variables to measure anthropogenic influence. The predictive performance of the combined snail...... are more likely to contract and/or move into cooler areas in the south and east. Importantly, we also note that even though climate per se matters, the impact of humans on habitat play a crucial role in determining the distribution of the intermediate host snails in Africa. Thus, a future contraction...

Efeito do hexazinone isolado e em mistura na eficiência fotossintética de Panicum maximum Effect of hexazinone applied alone and in combination on the photosynthetic efficiency of Panicum maximum

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M. Girotto

2012-06-01

Full Text Available Esta pesquisa teve como objetivo avaliar a velocidade e intensidade de ação do hexazinone isolado e em mistura com outros inibidores do fotossistema II, através da eficiência fotossintética de Panicum maximum em pós-emergência. O ensaio foi constituído de seis tratamentos: hexazinone (250 g ha-1, tebuthiuron (1,0 kg ha-1, hexazinone + tebuthiuron (125 g ha-1 + 0,5 kg ha-1, diuron (2.400 g ha-1, hexazinone + diuron (125 + 1.200 g ha-1, metribuzin (1.440 g ha-1, hexazinone + metribuzin (125 + 720 g ha-1 e uma testemunha. O experimento foi instalado em delineamento inteiramente casualizado, com quatro repetições. Após a aplicação dos tratamentos, as plantas foram transportadas para casa de vegetação sob condições controladas de temperatura e umidade, onde ficaram durante o período experimental, sendo realizadas as seguintes avaliações: taxa de transporte de elétrons e análise visual de intoxicação. A avaliação com o fluorômetro foi realizada nos intervalos de 1, 2, 6, 24, 48, 72, 120 e 168 horas após a aplicação, e as avaliações visuais, aos três e sete dias após a aplicação. Os resultados demonstraram diferença nos tratamentos, enfatizando a aplicação do diuron, que reduziu lentamente o transporte de elétrons comparado com os outros herbicidas e, em mistura com hexazinone, apresentou efeito sinérgico. Verificou-se com o uso do fluorômetro a intoxicação antecipada em plantas de P. maximum após a aplicação de herbicidas inibidores do fotossistema II de forma isolada e em mistura.This work aimed to evaluate the speed and intensity of action of hexazinone applied alone and in combination with other photo-system II inhibitors on the photosynthetic efficiency of Panicum maximum in post-emergence. The assay consisted of six treatments: hexazinone (250 g ha-1, tebuthiuron (1.0 kg ha-1, hexazinone + tebuthiuron (125 g ha-1+ 0.5 kg ha-1, diuron (2,400 g ha-1, hexazinone + diuron (125 + 1,200 g ha-1, metribuzin

Elimination of intermediate species in multiscale stochastic reaction networks

DEFF Research Database (Denmark)

Cappelletti, Daniele; Wiuf, Carsten

2016-01-01

such as the substrate-enzyme complex in the Michaelis-Menten mechanism. Such species are virtually in all real-world networks, they are typically short-lived, degraded at a fast rate and hard to observe experimentally. We provide conditions under which the Markov process of a multiscale reaction network...

Influence of salicylic and succinic acids on antioxidant enzymes activity, heat resistance and productivity of Panicum miliaceum L.

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Miroshnichenko N.N.

2011-05-01

Full Text Available The influence of treatment of millet (Panicum miliaceum L. seeds with the solutions of salicylic and succinic acids on the heat resistance of plantlets and activity of antioxidant enzymes – superoxide dismutase (SOD, catalase and peroxidase – in them have been investigated. In the micro-field experiment the influence of these acids on the millet yield was estimated. The action of salicylic (10 μM and succinic (1 mM acids caused the increase of plantlets resistance to the damaging heating that expressed in the rise of relative quantity of survived plantlets in 5 days after heating at the temperature of 47°С and in the reduced content of lipid peroxidation product malonic dialdehyde during the poststress period. The increase of activity of SOD, catalase and peroxidase took place in millet plantlets under the influence of salicylic and succinic acids. The increase of productivity of millet grain under the action of salicylic and succinic acids on 13,3-52,0 and 6,4-38,8% respectively depending on weather conditions in the field experiments was noted.

Anthracnose disease of switchgrass caused by the novel fungal species Colletotrichum navitas.

Science.gov (United States)

Crouch, Jo Anne; Beirn, Lisa A; Cortese, Laura M; Bonos, Stacy A; Clarke, Bruce B

2009-12-01

In recent years perennial grasses such as the native tallgrass prairie plant Panicum virgatum (switchgrass) have taken on a new role in the North American landscape as a plant-based source of renewable energy. Because switchgrass is a native plant, it has been suggested that disease problems will be minimal, but little research in this area has been conducted. Recently, outbreaks of switchgrass anthracnose disease have been reported from the northeastern United States. Incidences of switchgrass anthracnose are known in North America since 1886 through herbarium specimens and disease reports, but the causal agent of this disease has never been experimentally determined or taxonomically evaluated. In the present work, we evaluate the causal agent of switchgrass anthracnose, a new species we describe as Colletotrichum navitas (navitas=Latin for energy). Multilocus molecular phylogenetics and morphological characters show C. navitas is a novel species in the falcate-spored graminicolous group of the genus Colletotrichum; it is most closely related to the corn anthracnose pathogen Colletotrichum graminicola. We present a formal description and illustrations for C. navitas and provide experimental confirmation that this organism is responsible for switchgrass anthracnose disease.

Covalent functionalization of graphene with reactive intermediates.

Science.gov (United States)

Park, Jaehyeung; Yan, Mingdi

2013-01-15

Graphene, a material made exclusively of sp(2) carbon atoms with its π electrons delocalized over the entire 2D network, is somewhat chemically inert. Covalent functionalization can enhance graphene's properties including opening its band gap, tuning conductivity, and improving solubility and stability. Covalent functionalization of pristine graphene typically requires reactive species that can form covalent adducts with the sp(2) carbon structures in graphene. In this Account, we describe graphene functionalization reactions using reactive intermediates of radicals, nitrenes, carbenes, and arynes. These reactive species covalently modify graphene through free radical addition, CH insertion, or cycloaddition reactions. Free radical additions are among the most common reaction, and these radicals can be generated from diazonium salts and benzoyl peroxide. Electron transfer from graphene to aryl diazonium ion or photoactivation of benzoyl peroxide yields aryl radicals that subsequently add to graphene to form covalent adducts. Nitrenes, electron-deficient species generated by thermal or photochemical activation of organic azides, can functionalize graphene very efficiently. Because perfluorophenyl nitrenes show enhanced bimolecular reactions compared with alkyl or phenyl nitrenes, perfluorophenyl azides are especially effective. Carbenes are used less frequently than nitrenes, but they undergo CH insertion and C═C cycloaddition reactions with graphene. In addition, arynes can serve as a dienophile in a Diels-Alder type reaction with graphene. Further study is needed to understand and exploit the chemistry of graphene. The generation of highly reactive intermediates in these reactions leads to side products that complicate the product composition and analysis. Fundamental questions remain about the reactivity and regioselectivity of graphene. The differences in the basal plane and the undercoordinated edges of graphene and the zigzag versus arm-chair configurations

The Effect of Trichoderma on Heavy Metal Mobility and Uptake by Miscanthus giganteus, Salix sp., Phalaris arundinacea, and Panicum virgatum

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Malgorzata J. Kacprzak

2014-01-01

Full Text Available The effect of land application of biomaterials based on two strains of Trichoderma fungus on phytoremediation processes was studied. Six metals (Cd, Cr, Cu, Pb, Zn, and Ni were analysed in soil and soil leachate as well as in plant tissues. The translocation index (Ti and metal bioconcentration factors (BCF calculated for the inoculated plants were increased compared to the noninoculated control, except for Pb and Salix sp. Simultaneously, the mobilisation of metals in soil solution as an effect of biomaterials was noted. The highest values of Ti—339% (for Cr, 190% (for Ni, and 110% (for Cu—were achieved for the combination Miscanteus giganteus and Trichoderma MSO1. The results indicated that the application of fungus has positive effects on increasing the biomass, soil parameters (C, N, and P, and solubility of heavy metals in soil and therefore in enhancing phytoextraction for Miscanthus giganteus L., Panicum virgatum L., Phalaris arundinacea L., and Salix sp.

Transcriptomic analysis, genic SSR development, and genetic diversity of proso millet (Panicum miliaceum; Poaceae).

Science.gov (United States)

Hou, Siyu; Sun, Zhaoxia; Li, Yaoshen; Wang, Yijie; Ling, Hubin; Xing, Guofang; Han, Yuanhuai; Li, Hongying

2017-07-01

Proso millet ( Panicum miliaceum ; Poaceae) is a minor crop with good nutritional qualities and strong tolerance to drought stress and soil infertility. However, studies on genetic diversity have been limited due to a lack of efficient genetic markers. Illumina sequencing technology was used to generate short read sequences of proso millet, and de novo transcriptome assemblies were used to develop a de novo assembly of proso millet. Genic simple sequence repeat (SSR) markers were identified and used to detect polymorphism among 56 accessions. Population structure and genetic similarity coefficient were estimated. In total, 25,341 unique gene sequences and 4724 SSR loci were obtained from the transcriptome, of which 229 pairs of SSR primers were validated, which resulted in 14 polymorphic genic SSR primers exhibiting 43 total alleles. According to the ratio of polymorphic markers (6.1%, 14/229), there are potentially 288 polymorphic genic SSR markers available for genetic assay development in the future. Bayesian population analyses showed that the 56 accessions comprised two distinct groups. A genetic structure and cluster assay indicated that the accessions from the Loess Plateau of China shared a high genetic similarity coefficient with those from other regions and that there was no correlation between genetic diversity and geographic origin. The transcriptome sequencing data and millet-specific SSR markers developed in this study establish an excellent resource for gene discovery and may improve the development of breeding programs in proso millet in the future.

Notes on the genus Digitaria, with descriptions of new species

NARCIS (Netherlands)

Henrard, J.Th.

1934-01-01

Some years ago I had the opportunity to study more extensively a very interesting group of grasses, belonging to what is now accepted as a distinct genus, the genus Digitaria, formerly belonging as a subgenus to the genus Panicum. As to living plants of this group I was familiar with two european

Evaluation of ecophysiological characteristics of intercropping of millet (Panicum miliaceum L. and cowpea (Vigna unguiculata L.

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A. Ghanbari

2016-04-01

Full Text Available In order to evaluate millet (Panicum miliaceum L. and cowpea (Vigna unguiculata L. intercropping, an experiment was conducted during 2008-2009 at Agriculture Research Center of Zabol University, Iran. The experiment was as randomized complete block design with three replications. Treatment s consisted of sole crop of millet, sole crop of cowpea, 25% millet + 100% cowpea, 50% millet + 50% cowpea, 75% millet + 100% cowpea and 100% millet + 100% cowpea. The results showed that intercropping treatments had significant effect (P < 1% on millet and bean seed yield, LER, dry matter of weeds, PAR, temperature and (P < 5% on soil moisture content. The highest seed yield of millet and cowpea obtained from treatments of sole crops. The LER for most intercrops was greater than one which indicated that intercropping had advantage over sole crop. For weeds management and control the results indicated that weed suppressing effects in intercropping treatments is better than sole crops treatment, so that the lowest dry matter of weeds obtained from 100% millet + 100% cowpea treatment. PAR in all of stages showed that the highest PAR interception obtained from intercropping treatments specially 100% millet + 100% cowpea treatment. In addition to the lowest of soil moisture content and temperature obtained from this treatment.

Susceptibility of Staphylococcus species and subspecies to fleroxacin.

Science.gov (United States)

Bannerman, T L; Wadiak, D L; Kloos, W E

1991-01-01

Twenty-four Staphylococcus species or subspecies were examined for their susceptibilities to the fluoroquinolone fleroxacin (Ro 23-6240) by disk diffusion (5-micrograms disk) and by agar dilution for the determination of MICs. Resistant strains were further tested for their susceptibilities to oxacillin and the fluoroquinolone ciprofloxacin. Reference strains of the novobiocin-resistant species (Staphylococcus saprophyticus, Staphylococcus cohnii, Staphylococcus xylosus, Staphylococcus arlettae, and Staphylococcus gallinarum) had an intrinsic intermediate susceptibility (MIC, 4 micrograms/ml) to fleroxacin. Fleroxacin resistance was not observed in the reference strains of the novobiocin-susceptible species (MIC, 0.5 to 2.0 micrograms/ml). Clinical isolates of coagulase-negative species were generally less susceptible to fleroxacin than were reference strains. Seven percent of the Staphylococcus epidermidis clinical strains were resistant (MIC, greater than or equal to 8 micrograms/ml) to fleroxacin. Of these strains, 77% were resistant to oxacillin and 50% were resistant to ciprofloxacin. Thirty-four percent of the Staphylococcus haemolyticus clinical strains were resistant to fleroxacin, and 9% had intermediate susceptibility. Of the resistant strains, 95% were resistant to oxacillin and 77% were resistant to ciprofloxacin, while 23% had intermediate susceptibility to ciprofloxacin. Fleroxacin is an effective antimicrobial agent against most staphylococci. PMID:1759838

Production and bromatologic composition of grass-mombaça (Panicum maximum Jacq., submitted to different sources and doses of acidity corrective / Produção e composição bromatológica da forragem do capim-mombaça (Panicum maximum Jacq., submetidos a diferentes fontes e doses de corretivo de acidez

Directory of Open Access Journals (Sweden)

Francisco Maximino Fernandes

2010-04-01

Full Text Available The experiment was carried in protected (greenhouse atmosphere, in University of Engineering, UNESP of Ilha Solteira-SP, with the objective of evaluating sources (limestone and calcium silicate slag and doses (0,0 – 0,5 – 1,0 – 1,5 – 2,0 times the recommended dose of corrective in the bromatologic composition, tillering and production of dry matter of the grass mombaça (Panicum maximum Jacq.. The lineation was completely randomized design, with four repetitions. It was evaluated the tiller number, the production of dry matter, the gross protein, neutral detergent fiber (NDF and acid detergent fiber (ADF. The corrective influenced the tillering in almost all of the countings. The limestone provided larger production of dry matter in the doses of 1,5 and 2,0 times the recommended dose. The bromatologic composition of the forage was not influenced by the corrective and doses.O experimento foi conduzido em ambiente protegido (estufa, na Faculdade de Engenharia, UNESP de Ilha Solteira, com o objetivo de avaliar fontes (calcário e escória silicatada e doses (0,0 – 0,5 – 1,0 – 1,5 – 2,0 vezes a dose recomendada de corretivos na composição bromatológica, perfilhamento e produção de matéria seca do capim-mombaça (Panicum maximum Jacq.. O delineamento experimental utilizado foi inteiramente casualizado, com quatro repetições. Avaliou-se o número de perfilhos, a produção de matéria seca e os teores de proteína bruta (PB, fibra em detergente neutro (FDN e fibra em detergente ácido (FDA. Os corretivos influenciaram o perfilhamento em quase todas as contagens. O calcário proporcionou maior produção de matéria seca nas doses de 1,5 e 2,0 vezes a dose recomendada. A composição bromatológica da forragem não foi influenciada pelos corretivos e doses utilizadas.

First identification of Echinococcus multilocularis in rodent intermediate hosts in Sweden

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Andrea L. Miller

2016-04-01

Full Text Available Echinococcus multilocularis is a zoonotic tapeworm with a sylvatic lifecycle and an expanding range in Europe. Monitoring efforts following its first identification in 2011 in Sweden have focused on the parasite's definitive host, the red fox (Vulpes vulpes. However, identifying rodent intermediate hosts is important to recognize opportunities for parasite transmission. During 2013–2015, livers from a total of 1566 rodents from four regions in Sweden were examined for E. multilocularis metacestode lesions. Species identity of suspect parasite lesions was confirmed by PCR and sequencing. E. multilocularis positive lesions >6 mm in diameter were also examined histologically. One Microtus agrestis out of 187 (0.5%, 95%CI: 0–2.9%, 8/439 (1.8%, 95%CI: 0.8–3.6% Arvicola amphibius, 0/655 (0%, 95%CI: 0–0.6% Myodes glareolus, and 0/285 (0%, 95%CI: 0–1.3% Apodemus spp. contained E. multilocularis metacestode lesions. Presence of protoscoleces was confirmed in the infected M. agrestis and in three of eight infected A. amphibius. Six of the nine positive rodents were captured from the same field. This is the first report of E. multilocularis in intermediate hosts in Sweden. The cluster of positive rodents in one field shows that local parasite prevalence can be high in Sweden despite overall low national prevalence in foxes (<0.1%. The presence of protoscoleces in infected M. agrestis and A. amphibius indicate these species can serve as competent intermediate hosts in Sweden. However, their relative importance for E. multilocularis transmission in the Swedish environment is not yet possible to assess. In contrast, the negative findings in all M. glareolus and Apodemus spp. suggest that these species are of no importance.

Intermediate pond sizes contain the highest density, richness, and diversity of pond-breeding amphibians.

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Raymond D Semlitsch

Full Text Available We present data on amphibian density, species richness, and diversity from a 7140-ha area consisting of 200 ponds in the Midwestern U.S. that represents most of the possible lentic aquatic breeding habitats common in this region. Our study includes all possible breeding sites with natural and anthropogenic disturbance processes that can be missing from studies where sampling intensity is low, sample area is small, or partial disturbance gradients are sampled. We tested whether pond area was a significant predictor of density, species richness, and diversity of amphibians and if values peaked at intermediate pond areas. We found that in all cases a quadratic model fit our data significantly better than a linear model. Because small ponds have a high probability of pond drying and large ponds have a high probability of fish colonization and accumulation of invertebrate predators, drying and predation may be two mechanisms driving the peak of density and diversity towards intermediate values of pond size. We also found that not all intermediate sized ponds produced many larvae; in fact, some had low amphibian density, richness, and diversity. Further analyses of the subset of ponds represented in the peak of the area distribution showed that fish, hydroperiod, invertebrate density, and canopy are additional factors that drive density, richness and diversity of ponds up or down, when extremely small or large ponds are eliminated. Our results indicate that fishless ponds at intermediate sizes are more diverse, produce more larvae, and have greater potential to recruit juveniles into adult populations of most species sampled. Further, hylid and chorus frogs are found predictably more often in ephemeral ponds whereas bullfrogs, green frogs, and cricket frogs are found most often in permanent ponds with fish. Our data increase understanding of what factors structure and maintain amphibian diversity across large landscapes.

Intermediate neutron spectrum problems and the intermediate neutron spectrum experiment

International Nuclear Information System (INIS)

Jaegers, P.J.; Sanchez, R.G.

1996-01-01

Criticality benchmark data for intermediate energy spectrum systems does not exist. These systems are dominated by scattering and fission events induced by neutrons with energies between 1 eV and 1 MeV. Nuclear data uncertainties have been reported for such systems which can not be resolved without benchmark critical experiments. Intermediate energy spectrum systems have been proposed for the geological disposition of surplus fissile materials. Without the proper benchmarking of the nuclear data in the intermediate energy spectrum, adequate criticality safety margins can not be guaranteed. The Zeus critical experiment now under construction will provide this necessary benchmark data

Produção de forragem do capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia-1 pastejado em diferentes alturas Forage production of Tanzaniagrass (Panicum maximum Jacq. cv. Tanzania-1 grazed at different heights

Directory of Open Access Journals (Sweden)

Clovenilson Cláudio Perissato Cano

2004-12-01

Full Text Available Objetivou-se, com este experimento, avaliar a massa de forragem (MF, massa de lâmina verde (MLV, massa de colmo + bainha verde (MCV, massa de material morto (MMM, massa de forragem verde (MFV, relação folha/colmo (F/C, taxa de acúmulo de massa seca (TAMS, acúmulo de massa de forragem (AMF, índice de área foliar (IAF, porcentagem de solo descoberto (SD e porcentagem de solo coberto com liteira (SCL em pastagem de capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia-1 manejada em quatro alturas do dossel forrageiro (20, 40, 60 e 80 cm. O método de pastejo utilizado foi o de lotação contínua e taxa de lotação variável, com novilhos da raça Nelore com peso médio de 340 kg. Utilizou-se o delineamento experimental inteiramente casualizado com duas repetições e realizaram-se cinco avaliações. MLV, MCV, MMM, MFV, MF, IAF, TAMS e AMF aumentaram com o avanço da altura do dossel, sendo que a porcentagem de SD, SCL e material morto diminui em pastos mais altos. O manejo do capim-Tanzânia nas alturas de 40 e 60 cm, apresentou as melhores respostas de composição morfológica, garantindo boa oferta de folhas, de cobertura do solo e taxa de acúmulo de massa seca. As alturas de 20 e 80 cm não devem ser recomendadas para o manejo do capim-Tanzânia quando o objetivo for produção com qualidade e quantidade.This experiment was conducted out to evaluate the forage mass (FM, green leaf lamina mass (GLLM, green stem + leaf sheath mass (GSSM, mass of dead material (MDM, green forage mass (GMF, total forage mass (TFM, leaf/stem ratio (L/S, dry matter accumulation rate (DMAR, leaf area index (LAI, % of bare soil (BS and litter cover percentage (LCP in Tanzaniagrass pasture (Panicum maximum Jacq. cv. Tanzania-1 managed at four different sward heights (20, 40, 60 and 80 cm. The grazing method was the continuous stocking with variable stocking rate, and the grazing animals were Nellore steers with average weight of 340 kg. The completely

Aislamiento e identificación de cepas de Azospirillum sp. en pasto guinea (Panicum maximum Jacq. del Valle del Cesar Isolation and identification of Azospirillum sp. in Guinea grass (Panicum maximum Jacq. of the Valle del Cesar

Directory of Open Access Journals (Sweden)

Diana M Cárdenas

2010-09-01

Full Text Available Se evaluó el efecto de factores ambientales del Valle del Cesar y el manejo agronómico del pasto guinea (Panicum maximum Jacq., sobre la población bacteriana del género Azospirillum en medios de cultivo semisólidos NFb y LGI, para lo cual se utilizó un diseño experimental en parcelas divididas con un arreglo factorial de 2 (épocas climáticas: lluvia y sequía x 2 (manejos agronómicos: agroecólogico y extractivo x 3 (muestras analizadas: suelo rizosférico, raíces y hojas. Los resultados no revelaron diferencias estadísticas significativas, lo que indica que esta bacteria puede mantener su población en condiciones de estrés por diferentes mecanismos fisiológicos. A partir de estas muestras se obtuvieron 16 aislamientos pertenecientes al género Azospirillum, a los cuales se les evaluó su actividad de reducción de acetileno como indicador de la fijación biológica de nitrógeno y su capacidad en la producción de compuestos indólicos como promotores del crecimiento vegetal. Se seleccionaron las cepas SRGM2, SRGM3 y SRGM4 obtenidas de muestras de suelo rizosférico de pasto guinea de la Estación Experimental Motilonia de Corpoica, municipio Agustín Codazzi, departamento del Cesar. Estos aislamientos se caracterizaron molecularmente por el gen 16S rRNA y según el análisis BLAST en la base de datos del GenBank y presentaron 93% de similitud con A. lipoferum (SRGM2 y SRGM3 y 94% con A. brasilense (SRGM4.The effect of environmental factors of the Valle del Cesar and the agronomic management of Guinea grass (Panicum maximum Jacq., on the bacterial population of the Azospirillum genus in semisolid NFb and LGI culture media was evaluated, for which an experimental design was used in divided plots with a 2 (climatic seasons: rainy and dry x 2 (agronomic managements: agroecological and extractive x 3 (analyzed samples: rhizospheric soil, roots and leaves factorial arrangement. The results did not reveal significant statistical

Modeling phosphorus capture by plants growing in a multi-species riparian buffer

Science.gov (United States)

The NST 3.0 mechanistic nutrient uptake model was used to explore phosphorus (P) uptake to a depth of 120 cm over a 126-d growing season in simulated buffer communities composed of mixtures of cottonwood (Populus deltoids Bartr.), switchgrass (Panicum virgatum L.), and smooth brome (Bromis inermis L...

Organometallic copper I, II or III species in an intramolecular dechlorination reaction

KAUST Repository

Poater, Albert

2013-03-15

The present paper gives insight into an intramolecular dechlorination reaction involving Copper (I) and an ArCH2Cl moiety. The discussion of the presence of a CuIII organometallic intermediate becomes a challenge, and because of the lack of clear experimental detection of this proposed intermediate, and due to the computational evidence that it is less stable than other isomeric species, it can be ruled out for the complex studied here. Our calculations are completely consistent with the key hypothesis of Karlin et al. that TMPA-CuI is the substrate of intramolecular dechlorination reactions as well as the source to generate organometallic species. However the organometallic character of some intermediates has been refused because computationally these species are less stable than other isomers. Thus this study constitutes an additional piece towards the full understanding of a class of reaction of biological relevance. Further, the lack of high energy barriers and deep energy wells along the reaction pathway explains the experimental difficulties to trap other intermediates. © Springer-Verlag Berlin Heidelberg 2013.

Cryptic Species Due to Hybridization: A Combined Approach to Describe a New Species (Carex: Cyperaceae).

Science.gov (United States)

Maguilla, Enrique; Escudero, Marcial

2016-01-01

Disappearance of diagnostic morphological characters due to hybridization is considered to be one of the causes of the complex taxonomy of the species-rich (ca. 2000 described species) genus Carex (Cyperaceae). Carex furva s.l. belongs to section Glareosae. It is an endemic species from the high mountains of the Iberian Peninsula (Spain and Portugal). Previous studies suggested the existence of two different, cryptic taxa within C. furva s.l. Intermediate morphologies found in the southern Iberian Peninsula precluded the description of a new taxa. We aimed to determine whether C. furva s.l. should be split into two different species based on the combination of morphological and molecular data. We sampled ten populations across its full range and performed a morphological study based on measurements on herbarium specimens and silica-dried inflorescences. Both morphological and phylogenetic data support the existence of two different species within C. furva s.l. Nevertheless, intermediate morphologies and sterile specimens were found in one of the southern populations (Sierra Nevada) of C. furva s.l., suggesting the presence of hybrid populations in areas where both supposed species coexist. Hybridization between these two putative species has blurred morphological and genetic limits among them in this hybrid zone. We have proved the utility of combining molecular and morphological data to discover a new cryptic species in a scenario of hybridization. We now recognize a new species, C. lucennoiberica, endemic to the Iberian Peninsula (Sierra Nevada, Central system and Cantabrian Mountains). On the other hand, C. furva s.s. is distributed only in Sierra Nevada, where it may be threatened by hybridization with C. lucennoiberica. The restricted distribution of both species and their specific habitat requirements are the main limiting factors for their conservation.

Separating the effects of environment and space on tree species distribution: from population to community.

Science.gov (United States)

Lin, Guojun; Stralberg, Diana; Gong, Guiquan; Huang, Zhongliang; Ye, Wanhui; Wu, Linfang

2013-01-01

Quantifying the relative contributions of environmental conditions and spatial factors to species distribution can help improve our understanding of the processes that drive diversity patterns. In this study, based on tree inventory, topography and soil data from a 20-ha stem-mapped permanent forest plot in Guangdong Province, China, we evaluated the influence of different ecological processes at different spatial scales using canonical redundancy analysis (RDA) at the community level and multiple linear regression at the species level. At the community level, the proportion of explained variation in species distribution increased with grid-cell sizes, primarily due to a monotonic increase in the explanatory power of environmental variables. At the species level, neither environmental nor spatial factors were important determinants of overstory species' distributions at small cell sizes. However, purely spatial variables explained most of the variation in the distributions of understory species at fine and intermediate cell sizes. Midstory species showed patterns that were intermediate between those of overstory and understory species. At the 20-m cell size, the influence of spatial factors was stronger for more dispersal-limited species, suggesting that much of the spatial structuring in this community can be explained by dispersal limitation. Comparing environmental factors, soil variables had higher explanatory power than did topography for species distribution. However, both topographic and edaphic variables were highly spatial structured. Our results suggested that dispersal limitation has an important influence on fine-intermediate scale (from several to tens of meters) species distribution, while environmental variability facilitates species distribution at intermediate (from ten to tens of meters) and broad (from tens to hundreds of meters) scales.

Corrosion of steel drums containing simulated radioactive waste of low and intermediate level

International Nuclear Information System (INIS)

Farina, S.B.; Schulz Rodríguez, F.; Duffó, G.S.

2013-01-01

Ion-exchange resins are frequently used during the operation of nuclear power plants and constitute radioactive waste of low and intermediate level. For the final disposal inside the repository the resins are immobilized by cementation and placed inside steel drums. The eventful contamination of the resins with aggressive species may cause corrosion problems to the drums. In order to assess the incidence of this phenomenon and to estimate the lifespan of the steel drums, in the present work, the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins contaminated with different aggressive species was studied. The aggressive species studied were chloride ions (main ionic species of concern) and sulphate ions (produced during radiolysis of the cationic exchange-resins after cementation). The corrosion rate of the steel was monitored over a time period of 900 days and a chemical and morphological analysis of the corrosion products formed on the steel in each condition was performed. When applying the results obtained in the present work to estimate the corrosion depth of the drums containing the cemented radioactive waste after a period of 300 years (foreseen durability of the Low and Intermediate Level Radioactive Waste facility in Argentina), it was found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. (author)

Nitrenes, carbenes, diradicals, and ylides. Interconversions of reactive intermediates.

Science.gov (United States)

Wentrup, Curt

2011-06-21

Rearrangements of aromatic and heteroaromatic nitrenes and carbenes can be initiated with either heat or light. The thermal reaction is typically induced by flash vacuum thermolysis, with isolation of the products at low temperatures. Photochemical experiments are conducted either under matrix isolation conditions or in solution at ambient temperature. These rearrangements are usually initiated by ring expansion of the nitrene or carbene to a seven-membered ring ketenimine, carbodiimide, or allene (that is, a cycloheptatetraene or an azacycloheptatetraene when a nitrogen is involved). Over the last few years, we have found that two types of ring opening take place as well. Type I is an ylidic ring opening that yields nitrile ylides or diazo compounds as transient intermediates. Type II ring opening produces either dienylnitrenes (for example, from 2-pyridylnitrenes) or 1,7-(1,5)-diradicals (such as those formed from 2-quinoxalinylnitrenes), depending on which of these species is better stabilized by resonance. In this Account, we describe our achievements in elucidating the nature of the ring-opened species and unraveling the connections between the various reactive intermediates. Both of these ring-opening reactions are found, at least in some cases, to dominate the subsequent chemistry. Examples include the formation of ring-opened ketenimines and carbodiimides, as well as the ring contraction reactions that form five-membered ring nitriles (such as 2- and 3-cyanopyrroles from pyridylnitrenes, N-cyanoimidazoles from 2-pyrazinyl and 4-pyrimidinylnitrenes, N-cyanopyrazoles from 2-pyrimidinylnitrenes and 3-pyridazinylnitrenes, and so forth). The mechanisms of formation of the open-chain and ring-contraction products were unknown at the onset of this study. In the course of our investigation, several reactions with three or more consecutive reactive intermediates have been unraveled, such as nitrene, seven-membered cyclic carbodiimide, and open-chain nitrile ylide

Mechanical response of common millet (Panicum miliaceum) seeds under quasi-static compression: Experiments and modeling.

Science.gov (United States)

Hasseldine, Benjamin P J; Gao, Chao; Collins, Joseph M; Jung, Hyun-Do; Jang, Tae-Sik; Song, Juha; Li, Yaning

2017-09-01

The common millet (Panicum miliaceum) seedcoat has a fascinating complex microstructure, with jigsaw puzzle-like epidermis cells articulated via wavy intercellular sutures to form a compact layer to protect the kernel inside. However, little research has been conducted on linking the microstructure details with the overall mechanical response of this interesting biological composite. To this end, an integrated experimental-numerical-analytical investigation was conducted to both characterize the microstructure and ascertain the microscale mechanical properties and to test the overall response of kernels and full seeds under macroscale quasi-static compression. Scanning electron microscopy (SEM) was utilized to examine the microstructure of the outer seedcoat and nanoindentation was performed to obtain the material properties of the seedcoat hard phase material. A multiscale computational strategy was applied to link the microstructure to the macroscale response of the seed. First, the effective anisotropic mechanical properties of the seedcoat were obtained from finite element (FE) simulations of a microscale representative volume element (RVE), which were further verified from sophisticated analytical models. Then, macroscale FE models of the individual kernel and full seed were developed. Good agreement between the compression experiments and FE simulations were obtained for both the kernel and the full seed. The results revealed the anisotropic property and the protective function of the seedcoat, and showed that the sutures of the seedcoat play an important role in transmitting and distributing loads in responding to external compression. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of pollination mode on progeny of Panicum coloratum var. makarikariense: Implications for conservation and breeding

Directory of Open Access Journals (Sweden)

Lorena V. Armando

2017-09-01

Full Text Available Panicum coloratum var. makarikariense, a perennial grass native to Africa, is adapted to a wide range of soil and climatic conditions with potential to be used as forage in tropical and semi-arid regions around the world. Our objective was to understand how the pollination mode affects viable seed production and further survival of the progeny. We evaluated self- and open-pollinated progenies from different accessions by measuring the seed production of the parents and their germination performance, germination rate and seedling survival. Parents and progeny were also fingerprinted with Simple Sequence Repeats (SSR. Progeny produced through open-pollination resulted in significantly more filled seeds and superior seedling survival than self-pollination. These results indicate that accessions studied here rely heavily on cross-pollination, whereas the contribution of self-pollinated offspring to the population is likely to be low. SSR profiles showed that, on average, 85% of the progeny (arising from cross-pollination possessed paternal specific markers and 100% of them were genetically different from the maternal genotype. All plants examined had 4x = 36 chromosomes. Overall, our findings indicate that var. makarikariense is able to generate highly polymorphic progeny through segregation and recombination. This study provides reference information for the formulation of appropriate strategies for pasture germplasm management, conservation and development of breeding programs. 

Kinetic and mechanistic studies of reactive intermediates in photochemical and transition metal-assisted oxidation, decarboxylation and alkyl transfer reactions

Energy Technology Data Exchange (ETDEWEB)

Carraher, Jack McCaslin [Iowa State Univ., Ames, IA (United States)

2014-01-01

Reactive species like high-valent metal-oxo complexes and carbon and oxygen centered radicals are important intermediates in enzymatic systems, atmospheric chemistry, and industrial processes. Understanding the pathways by which these intermediates form, their relative reactivity, and their fate after reactions is of the utmost importance. Herein are described the mechanistic detail for the generation of several reactive intermediates, synthesis of precursors, characterization of precursors, and methods to direct the chemistry to more desirable outcomes yielding ‘greener’ sources of commodity chemicals and fuels.

Protein phosphatase dependent circadian regulation of intermediate-term associative memory

OpenAIRE

Michel, Maximilian; Gardner, Jacob S.; Green, Charity L.; Organ, Chelsea L.; Lyons, Lisa C.

2013-01-01

The endogenous circadian clock is a principal factor modulating memory across species. Determining the processes through which the circadian clock modulates memory formation is a key issue in understanding and identifying mechanisms to improve memory. We used the marine mollusk Aplysia californica to investigate circadian modulation of intermediate-term memory (ITM) and the mechanisms through which the circadian clock phase specifically suppresses memory using the operant learning paradigm, l...

Criegee Intermediates: What Direct Production and Detection Can Teach Us About Reactions of Carbonyl Oxides

Science.gov (United States)

Taatjes, Craig A.

2017-05-01

The carbonyl oxide intermediates in the ozonolysis of alkenes, often known as Criegee intermediates, are potentially important reactants in Earth's atmosphere. For decades, careful analysis of ozonolysis systems was employed to derive an understanding of the formation and reactions of these species. Recently it has proved possible to synthesize at least some of these intermediates separately from ozonolysis, and hence to measure their reaction kinetics directly. Direct measurements have allowed new or more detailed understanding of each type of gas-phase reaction that carbonyl oxides undergo, often acting as a complement to highly detailed ozonolysis experiments. Moreover, the use of direct characterization methods to validate increasingly accurate theoretical investigations can enhance their impact well beyond the set of specific reactions that have been measured. Reactions that initiate particles or fuel their growth could be a new frontier for direct measurements of Criegee intermediate chemistry.

Adaptation of C4 Bioenergy Crop Species to Various Environments within the Southern Great Plains of USA

Directory of Open Access Journals (Sweden)

Sumin Kim

2017-01-01

Full Text Available As highly productive perennial grasses are evaluated as bioenergy feedstocks, a major consideration is biomass yield stability. Two experiments were conducted to examine some aspects of yield stability for two biofuel species: switchgrass (Panicum vigratum L. and Miscanthus x giganteus (Mxg. Biomass yields of these species were evaluated under various environmental conditions across the Southern Great Plains (SGP, including some sites with low soil fertility. In the first experiment, measured yields of four switchgrass ecotypes and Mxg varied among locations. Overall, plants showed optimal growth performance in study sites close to their geographical origins. Lowland switchgrass ecotypes and Mxg yields simulated by the ALMANAC model showed reasonable agreement with the measured yields across all study locations, while the simulated yields of upland switchgrass ecotypes were overestimated in northern locations. In the second experiment, examination of different N fertilizer rates revealed switchgrass yield increases over the range of 0, 80, or 160 kg N ha−1 year−1, while Mxg only showed yield increases between the low and medium N rates. This provides useful insights to crop management of two biofuel species and to enhance the predictive accuracy of process-based models, which are critical for developing bioenergy market systems in the SGP.

Intermediality and media change

OpenAIRE

2012-01-01

This book is about intermediality as an approach to analysing and understanding media change. Intermediality and Media Change is critical of technological determinism that characterises 'new media discourse' about the ongoing digitalization, framed as a revolution and creating sharp contrasts between old and new media. Intermediality instead emphasises paying attention to continuities between media of all types and privileges a comparative perspective on technological changes in media over ti...

Intermediate Fragment

DEFF Research Database (Denmark)

Kruse Aagaard, Anders

2015-01-01

This text and its connected exhibition are aiming to reflect both on the thoughts, the processes and the outcome of the design and production of the artefact ‘Intermediate Fragment’ and making as a contemporary architectural tool in general. Intermediate Fragment was made for the exhibition ‘Enga...... of realising an exhibition object was conceived, but expanded, refined and concretised through this process. The context of the work shown here is an interest in a tighter, deeper connection between experimentally obtained material knowledge and architectural design....

Governance-Default Risk Relationship and the Demand for Intermediated and Non-Intermediated Debt

Directory of Open Access Journals (Sweden)

Husam Aldamen

2012-09-01

Full Text Available This paper explores the impact of corporate governance on the demand for intermediated debt (asset finance, bank debt, non-bank private debt and non-intermediated debt (public debt in the Australian debt market. Relative to other countries the Australian debt market is characterised by higher proportions of intermediated or private debt with a lower inherent level of information asymmetry in that private lenders have greater access to financial information (Gray, Koh & Tong 2009. Our firm level, cross-sectional evidence suggests that higher corporate governance impacts demand for debt via the mitigation of default risk. However, this relationship is not uniform across all debt types. Intermediated debt such as bank and asset finance debt are more responsive to changes in governance-default risk relationship than non-bank and non-intermediated debt. The implication is that a firm’s demand for different debt types will reflect its governance-default risk profile.

Alimentation des lapins (Oryctolagus cuniculus L.) à base de Azolla ...

African Journals Online (AJOL)

Rabbits fed with the diet supplemented with Panicum maximum had an ... sustainable aquaculture production is that obtained with rabbit manures from the R3 diet ..... performance of three fish species. .... Organic Fertilizers used in the Urban.

Large-scale determinants of intestinal schistosomiasis and intermediate host snail distribution across Africa: does climate matter?

Science.gov (United States)

Stensgaard, Anna-Sofie; Utzinger, Jürg; Vounatsou, Penelope; Hürlimann, Eveline; Schur, Nadine; Saarnak, Christopher F L; Simoonga, Christopher; Mubita, Patricia; Kabatereine, Narcis B; Tchuem Tchuenté, Louis-Albert; Rahbek, Carsten; Kristensen, Thomas K

2013-11-01

The geographical ranges of most species, including many infectious disease agents and their vectors and intermediate hosts, are assumed to be constrained by climatic tolerances, mainly temperature. It has been suggested that global warming will cause an expansion of the areas potentially suitable for infectious disease transmission. However, the transmission of infectious diseases is governed by a myriad of ecological, economic, evolutionary and social factors. Hence, a deeper understanding of the total disease system (pathogens, vectors and hosts) and its drivers is important for predicting responses to climate change. Here, we combine a growing degree day model for Schistosoma mansoni with species distribution models for the intermediate host snail (Biomphalaria spp.) to investigate large-scale environmental determinants of the distribution of the African S. mansoni-Biomphalaria system and potential impacts of climatic changes. Snail species distribution models included several combinations of climatic and habitat-related predictors; the latter divided into "natural" and "human-impacted" habitat variables to measure anthropogenic influence. The predictive performance of the combined snail-parasite model was evaluated against a comprehensive compilation of historical S. mansoni parasitological survey records, and then examined for two climate change scenarios of increasing severity for 2080. Future projections indicate that while the potential S. mansoni transmission area expands, the snail ranges are more likely to contract and/or move into cooler areas in the south and east. Importantly, we also note that even though climate per se matters, the impact of humans on habitat play a crucial role in determining the distribution of the intermediate host snails in Africa. Thus, a future contraction in the geographical range size of the intermediate host snails caused by climatic changes does not necessarily translate into a decrease or zero-sum change in human

The Mechanisms of Salinity Tolerance in the Xero-halophyte Blue Panicgrass (Panicum antidotale Retz

Directory of Open Access Journals (Sweden)

Hamid R. ESHGHIZADEH

2012-05-01

Full Text Available Identifying the physiological traits associated with salt tolerance is important in optimal management of biosaline systems and optimum utilization of saline water resources in dry and saline areas. Therefore, some indices of photosynthetic activity, dry matter production and accumulation of sodium and potassium ions in Blue panicgrass (Panicum antidotale Retz were evaluated in five levels of salinity treatment (0, 70, 140, 210 and 280 mM NaCl solution under greenhouse conditions. The results showed that at 28 and 35 days after salt stress, plant leaf area reduced in the highest salinity treatment, 93 and 96% respectively, compared with control. Leaf stomatal conductance, CO2 fixation and quantum efficiency of photosystem II were decreased by increasing salinity. It caused also a reduction in chlorophyll content (Chl a, Chl b in leaves of Blue panicgrass. Content of carotenoids showed binary patterns to different salinity levels, slightly increased in 70-140 mM NaCl and decreased again in 210-280 mM, respectively. Increasing levels of salinity, increased sodium content in both roots and shoots but the shoots potassium content decreased. Decline in photosynthesis indices caused the reduction of root and shoot dry weight. This decrease resulted from lower leaf area (r=0.91**, lower stomatal conductance (r=0.78**, lower CO2 fixed in photosynthesis (r=0.63**, lower quantum efficiency of photosystem II (r=0.54** and lower Chl a (r=0.45**, respectively. Data analysis base on using stepwise regression introduced leaf area (?=0.560, chlorophyll a content (?=0.245 and shoot potassium content (?= 0.264 as main effective components of salinity tolerance in Blue panicgrass.

Miocene isotope zones, paleotemperatures, and carbon maxima events at intermediate water-depth, Site 593, Southwest Pacific

International Nuclear Information System (INIS)

Cooke, P.J.; Nelson, C.S.; Crundwell, M.P.

2008-01-01

Oxygen and carbon isotopic stratigraphies are presented from both benthic and planktic foraminifera for the late early Miocene to earliest Pliocene interval (c. 19-5 Ma) of intermediate water-depth DSDP Site 593 in the southern Tasman Sea. The benthic values are interpreted as recording Miocene Southern Component Intermediate Water, while the planktic species record the Miocene mode and surface water signals. Comparisons are made between temperate Site 593 and the intermediate-depth polar Site 747 in the southern Indian Ocean. Glacial Mi zones Mi1b-Mi6, representing extreme glacial events, are evident in both the Site 593 intermediate and surface water records. Miocene Southern Component Intermediate Water δ 18 O values are generally lighter than the Holocene equivalent (Antarctic Intermediate Water), indicating slightly warmer intermediate waters and/ or less global ice volume. The benthic-planktic gradient is interpreted as indicating a less stratified Tasman Sea during the Miocene. The benthic δ 13 C record contains most of the global carbon maxima (CM) events, CM1-7 (CM1-6 = the Monterey Excursion). Like global deep-water records, the Tasman Sea intermediate water δ 13 C values indicate that most CM events correspond with Mi glacials, including Mi4 at Site 593, not reported previously. Intermediate waters play an important role in propagating climatic changes from the polar regions to the tropics, and the Site 593 dataset provides a full water column record of the structure of Miocene intermediate to surface watermasses prior to the modern situation. (author). 132 refs., 8 figs., 4 tabs

Management applicability of the intermediate disturbance hypothesis across Mongolian rangeland ecosystems.

Science.gov (United States)

Sasaki, Takehiro; Okubo, Satoru; Okayasu, Tomoo; Jamsran, Undarmaa; Ohkuro, Toshiya; Takeuchi, Kazuhiko

2009-03-01

The current growing body of evidence for diversity-disturbance relationships suggests that the peaked pattern predicted by the intermediate disturbance hypothesis (IDH) may not be the rule. Even if ecologists could quantify the diversity-disturbance relationship consistent with the IDH, the applicability of the IDH to land management has rarely been addressed. We examined two hypotheses related to the generality and management applicability of the IDH to Mongolian rangeland ecosystems: that the diversity-disturbance relationship varies as a function of landscape condition and that some intermediate scales of grazing can play an important role in terms of sustainable rangeland management through a grazing gradient approach. We quantified the landscape condition of each ecological site using an ordination technique and determined two types of landscape conditions: relatively benign and harsh environmental conditions. At the ecological sites characterized by relatively benign environmental conditions, diversity-disturbance relationships were generally consistent with the IDH, and maximum diversity was observed at some intermediate distance from the source of the grazing gradient. In contrast, the IDH was not supported at most (but not all) sites characterized by relatively harsh environmental conditions. The intermediate levels of grazing were generally located below the ecological threshold representing the points or zones at which disturbance should be limited to prevent drastic changes in ecological conditions, suggesting that there is little "conundrum" with regard to intermediate disturbance in the studied systems in terms of land management. We suggest that the landscape condition is one of the primary factors that cause inconsistencies in diversity-disturbance relationships. The ecological threshold can extend its utility in rangeland management because it also has the compatibility with the maintenance of species diversity. This study thus suggests that some

High Prevalence of Porocephalus crotali Infection on a Barrier Island (Cumberland Island) off the Coast of Georgia, with Identification of Novel Intermediate Hosts.

Science.gov (United States)

Yabsley, Michael J; Ellis, Angela E; Cleveland, Christopher A; Ruckdeschel, Carol

2015-10-01

Porocephalus crotali is a pentastomid parasite that uses crotaline snakes as definitive hosts and a variety of rodents as intermediate hosts. A study of definitive and intermediate pentastome hosts on Cumberland Island, Georgia, revealed high prevalence of P. crotali infection in crotalid snakes as well as several mammalian species. Despite the presence of numerous nymphs in some animals, clinical signs of disease were not observed. In intermediate hosts, the liver, mesentery, and reproductive organs were most commonly infected. No gross evidence of tissue damage was noted in association with the numerous encysted nymphal pentastomes, and histopathology demonstrated minimal reaction to the encysted nymphs. Partial 18S rRNA gene sequences confirmed the parasites were P. crotali. In contrast to many previous reports in rodents, the prevalence on this barrier island was high, and this is the first report of Virginia opossums (Didelphis virginiana) and any insectivore species as intermediate hosts. Although generally not considered pathogenic, the long-term consequences of high nymph intensities on individuals deserve attention.

Molecular analyses reveal high species diversity of trematodes in a sub-Arctic lake

Science.gov (United States)

Soldánová, Miroslava; Georgieva, Simona; Roháčováa, Jana; Knudsen, Rune; Kuhn, Jesper A.; Henriksen, Eirik H.; Siwertsson, Anna; Shaw, Jenny C.; Kuris, Armand M.; Amundsen, Per-Arne; Scholz, Tomáš; Lafferty, Kevin D.; Kostadinova, Aneta

2017-01-01

To identify trematode diversity and life-cycles in the sub-Arctic Lake Takvatn, Norway, we characterised 120 trematode isolates from mollusc first intermediate hosts, metacercariae from second intermediate host fishes and invertebrates, and adults from fish and invertebrate definitive hosts, using molecular techniques. Phylogenies based on nuclear and/or mtDNA revealed high species richness (24 species or species-level genetic lineages), and uncovered trematode diversity (16 putative new species) from five families typical in lake ecosystems (Allocreadiidae, Diplostomidae, Plagiorchiidae, Schistosomatidae and Strigeidae). Sampling potential invertebrate hosts allowed matching of sequence data for different stages, thus achieving molecular elucidation of trematode life-cycles and exploration of host-parasite interactions. Phylogenetic analyses also helped identify three major mollusc intermediate hosts (Radix balthica, Pisidium casertanum and Sphaerium sp.) in the lake. Our findings increase the known trematode diversity at the sub-Arctic Lake Takvatn, showing that digenean diversity is high in this otherwise depauperate sub-Arctic freshwater ecosystem, and indicating that sub-Arctic and Arctic ecosystems may be characterised by unique trematode assemblages.

The effect of Acacia Karroo supplementation and thermal ...

African Journals Online (AJOL)

Bathesh

2012-08-14

Aug 14, 2012 ... 2Animal Sciences Programme, North West University, P. Bag X2046, Mmabatho North West ... communal rangelands in South Africa and is preferred by goats. ... species on the farm are A. karroo, Themeda triandra, Panicum.

Transcriptomic analysis, genic SSR development, and genetic diversity of proso millet (Panicum miliaceum; Poaceae)1

Science.gov (United States)

Hou, Siyu; Sun, Zhaoxia; Li, Yaoshen; Wang, Yijie; Ling, Hubin; Xing, Guofang; Han, Yuanhuai; Li, Hongying

2017-01-01

Premise of the study: Proso millet (Panicum miliaceum; Poaceae) is a minor crop with good nutritional qualities and strong tolerance to drought stress and soil infertility. However, studies on genetic diversity have been limited due to a lack of efficient genetic markers. Methods: Illumina sequencing technology was used to generate short read sequences of proso millet, and de novo transcriptome assemblies were used to develop a de novo assembly of proso millet. Genic simple sequence repeat (SSR) markers were identified and used to detect polymorphism among 56 accessions. Population structure and genetic similarity coefficient were estimated. Results: In total, 25,341 unique gene sequences and 4724 SSR loci were obtained from the transcriptome, of which 229 pairs of SSR primers were validated, which resulted in 14 polymorphic genic SSR primers exhibiting 43 total alleles. According to the ratio of polymorphic markers (6.1%, 14/229), there are potentially 288 polymorphic genic SSR markers available for genetic assay development in the future. Bayesian population analyses showed that the 56 accessions comprised two distinct groups. Discussion: A genetic structure and cluster assay indicated that the accessions from the Loess Plateau of China shared a high genetic similarity coefficient with those from other regions and that there was no correlation between genetic diversity and geographic origin. The transcriptome sequencing data and millet-specific SSR markers developed in this study establish an excellent resource for gene discovery and may improve the development of breeding programs in proso millet in the future. PMID:28791202

Dispersal ability determines the scaling properties of species abundance distributions

DEFF Research Database (Denmark)

Borda-De-Água, Luís; Whittaker, Robert James; Cardoso, Pedro

2017-01-01

with computer simulations, low dispersal ability species generate a hump for intermediate abundance classes earlier than the distributions of high dispersal ability species. Importantly, when plotted as function of sample size, the raw moments of the SADs of arthropods have a power law pattern similar...

Efecto residual de dos rocas fosfóricas puras y parcialmente aciduladas, comparadas con SFT, sobre la aprovechabilidad del P por Panicum maximum L., en un oxisol de los Llanos Orientales de Colombia

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Alejo M. Doris

1986-03-01

Full Text Available Panicum maximum L. se sembró, en condiciones de invernadero, en un Oxisol de los Llanos Orientales de Colombia, 18 meses después de la aplicación de las fuentes (rocas fosfóricas de Pesca - Colombia y Sechura - Perú crudas y aciduladas al 20 % con H3 P04, en dosis de 25, 50 Y 100 ppm de P. La roca fosfórica Sechura cruda y parcialmente acidulada junto con SFT, tuvieron el mejor efecto residual sobre el rendimiento y captación de P y mantuvieron los más altos niveles de P asimilable en el suelo al final del ensayo. Con las dosis superiores se obtuvo un nivel más alto de P asimilable en el suelo y mayor absorción de P por la planta.In order to study the residual effect of the Pesca (Colombia and Sechura (Perú phosphate rocks, both crude and acidulated in 20 % by H3P04, comparatively with SFT, Panicum rnaximum L. was planted under glasshouse conditions, in an Oxisol from the Eastern plains of Colombia, 18 months after sources application, with rates of 25. 50 and 100 ppm of P. Crude and partially acidulated Sechura phosphate rock, together with TSP, had the best residual effect on yield and P absorption and had the highest available P levels in the soil at the end of the trial. The highest available P level in the soil and P uptake by the plant was obtained with higher P rates.

MHD intermediate shock discontinuities: Pt. 1

International Nuclear Information System (INIS)

Kennel, C.F.; Blandford, R.D.; Coppi, P.

1989-01-01

Recent numerical investigations have focused attention once more on the role of intermediate shocks in MHD. Four types of intermediate shock are identified using a graphical representation of the MHD Rankine-Hugoniot conditions. This same representation can be used to exhibit the close relationship of intermediate shocks to switch-on shocks and rotational discontinuities. The conditions under which intermediate discontinuities can be found are elucidated. The variations in velocity, pressure, entropy and magnetic-field jumps with upstream parameters in intermediate shocks are exhibited graphically. The evolutionary arguments traditionally advanced against intermediate shocks may fail because the equations of classical MHD are not strictly hyperbolic. (author)

Diversité floristique et dégré d\\'infestation par les mauvaises herbes ...

African Journals Online (AJOL)

Quantitative floristic analysis shows that the more frequent species are Chromolaena odorata, Panicum laxum, Pouzolzia guineensis, Solanum erianthum, Lapotea aestuens, Spigelia anthelmia and Mariscus cylindristachyus and the weeds that more cause damage are Chromolaena odorata, Euphorbia heterophylla, ...

Radiolysis studies on reactive intermediates. Final report, February 1, 1970-August 31, 1980

International Nuclear Information System (INIS)

Kevan, L.

1980-08-01

Research highlights are briefly reviewed concerning studies of excess and solvated electrons, development of new electron spin resonance methods for maximizing the geometrical information about the surroundings of paramagnetic species in disordered systems, atom and ion solvation, and studies on other reactive intermediates. Titles of 155 research publications and 182 scientific talks presented on these areas are given

Valor nutritivo do capim-Tanzânia (Panicum maximum Jacq cv. Tanzânia-1 manejado em alturas de pastejo - DOI: 10.4025/actascianimsci.v25i2.205 Nutritive value of tanzania grass (Panicum maximum Jacq cv. Tanzania-1 handled in different pasture heights - DOI: 10.4025/actascianimsci.v25i2.205

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Geraldo Tadeu dos Santos

2003-04-01

Full Text Available O trabalho objetivou avaliar o efeito de diferentes alturas do pasto (24cm e 26cm; 43cm e 45cm; 52cm e 62cm; 73cm e 78cm e períodos de avaliação (28, 56, 84 e 112 dias em capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia - 1 nos teores de proteína bruta (PB, fibra em detergente neutro (FDN, fibra em detergente ácido (FDA, digestibilidade in vitro da matéria seca (DIVMS, Ca, P, K e Mg nas porções lâmina e colmo. Foram utilizados novilhos da raça Nelore (em pastejo contínuo com taxa de lotação variável pela técnica put and take. O delineamento experimental utilizado foi inteiramente casualizado com 2 repetições. O aumento na altura de manejo provocou redução dos teores de PB e aumento dos níveis de FDA e FDN nas lâminas e nos colmos. As melhores alturas de manejo, de acordo com os resultados relativos à qualidade da forragem, variaram de 40cm e 60cm.The objective of this research was to evaluate the effect of different pasture heights (24cm and 26cm; 43cm and 45cm; 52cm and 62cm; 73cm and 78cm and sampling periods (28, 56, 84 and 112 days in Tanzania grass (Panicum maximum Jacq. cv. Tanzânia - 1 on content of crude protein (CP, neutral detergent fiber (NDF, acid detergent fiber (ADF, in vitro dry matter digestibility (IVMD, Ca, P, K and Mg on leaf blade and stem part. Nelore steers were used (in continuous grazing with variable stocking rates, using put and take technique. The experimental design was completely randomized, with two replications. The increments on the pasture height decreased CP content and increased ADF and NDF contents, both to the leaf blade and to the stems. The leaf blade quality was also influenced by different sampling times. The best pasture management height according to forage quality were between 40cm to 60cm.

Competition-colonization trade-offs, competitive uncertainty, and the evolutionary assembly of species.

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Pradeep Pillai

Full Text Available We utilize a standard competition-colonization metapopulation model in order to study the evolutionary assembly of species. Based on earlier work showing how models assuming strict competitive hierarchies will likely lead to runaway evolution and self-extinction for all species, we adopt a continuous competition function that allows for levels of uncertainty in the outcome of competition. We then, by extending the standard patch-dynamic metapopulation model in order to include evolutionary dynamics, allow for the coevolution of species into stable communities composed of species with distinct limiting similarities. Runaway evolution towards stochastic extinction then becomes a limiting case controlled by the level of competitive uncertainty. We demonstrate how intermediate competitive uncertainty maximizes the equilibrium species richness as well as maximizes the adaptive radiation and self-assembly of species under adaptive dynamics with mutations of non-negligible size. By reconciling competition-colonization tradeoff theory with co-evolutionary dynamics, our results reveal the importance of intermediate levels of competitive uncertainty for the evolutionary assembly of species.

Soil oribatid mite communities under three species of legumes in an ultisol in Brazil.

Science.gov (United States)

Badejo, M Adetola; Espindola, Jose Antonio Azevedo; Guerra, Jose Guilherme Marinho; De Aquino, Adriana Maria; Correa, Maria Elizabeth Fernandes

2002-01-01

Oribatid mite densities in the topsoil and their activity at the soil surface were monitored under three species of perennial legume cover crops namely, Arachis pintoi, Macroptilium atropupureum and Pueraria phaseoloides, grass (Panicum maximum) and bare plots on three occasions in 1998 and 1999 in a derived savanna zone in Brazil. Both densities and activity at the soil surface were higher in the early but cool dry season in April 1998 than in the early wet but warm season in November 1998 and 1999. Three taxonomic groups of macropyline oribatid mites, namely Nothrus, Archegozetes and Masthermannia as well as a brachypyline taxon, Scheloribates were suggested as possible indicators of effect of legumes on soil biota because their populations increased under the legumes and/or the irresidues. Nothrus in particular increased in abundance more than any other taxon in the presence of residues of A. pintoi. Each legume supported a unique oribatid mite community in terms of species composition and relative abundance. The large numbers of Archegozeres trapped from all the legume and grass plots in April and November 1998 were also attributed to highly conducive conditions provided by the vegetation cover and their residues. The results suggest that the oribatid mite community of the study area was numerically stable as the peak populations of different species were not synchronized. Many taxonomic groups of pycnonotic brachypyline mites were absent. Legume cover crops, especially A. pintoi, and their residues have potential in restoring oribatid mite populations to precultivation levels.

Effect of short-duration overnight cattle kraaling on grass production ...

African Journals Online (AJOL)

... grass species, such as Urochloa mosambicensis and Panicum maximum, were more abundant in abandoned kraal sites than the surrounding vegetation. We conclude that shortduration overnight cattle kraaling improves grass quality and biomass. Keywords: biomass, crude protein, diversity, fibre, nutrient hotspots ...

Complete genome sequence of switchgrass mosaic virus, a member of a proposed new species in the genus Marafivirus.

Science.gov (United States)

Agindotan, Bright O; Gray, Michael E; Hammond, Rosemarie W; Bradley, Carl A

2012-09-01

The complete genome sequence of a virus recently detected in switchgrass (Panicum virgatum) was determined and found to be closely related to that of maize rayado fino virus (MRFV), genus Marafivirus, family Tymoviridae. The genomic RNA is 6408 nucleotides long. It contains three predicted open reading frames (ORFs 1-3), encoding proteins of 227 kDa, 43.9 kDa, and 31.5 kDa, compared to two ORFs (1 and 2) for MRFV. The complete genome shares 76 % sequence identity with MRFV. The nucleotide sequence of ORF2 of this virus and the amino acid sequence of its encoded protein are 49 % and 77 % identical, respectively, to those of MRFV. The virus-encoded polyprotein and capsid protein aa sequences are 83 % and 74-80 % identical, respectively, to those of MRFV. Although closely related to MRFV, the amino acid sequence of its capsid protein (CP) forms a clade that is separate from that of MRFV. Based on the International Committee on Taxonomy of Viruses (ICTV) sequence-related criteria for delineation of species within the genus Marafivirus, the virus qualifies as a member of a new species, and the name Switchgrass mosaic virus (SwMV) is proposed.

Mimulus peregrinus (Phrymaceae: A new British allopolyploid species

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Mario Vallejo-Marin

2012-07-01

Full Text Available Polyploidization plays an important role in species formation as chromosome doubling results in strong reproductive isolation between derivative and parental taxa. In this note I describe a new species, Mimulus peregrinus (Phrymaceae, which represents the first recorded instance of a new British polyploid species of Mimulus (2n = 6x = 92 that has arisen since the introduction of this genus into the United Kingdom in the 1800’s. M. peregrinus presents floral and vegetative characteristics intermediate between M. guttatus and M. luteus, but can be distinguished from all naturalized British Mimulus species and hybrids based on a combination of reproductive and vegetative traits. M. peregrinus displays high pollen and seed fertility as well as traits usually associated with genome doubling such as increased pollen and stomata size. The intermediate characteristics of M. peregrinus between M. guttatus (2n = 2x = 28 and M. luteus (2n = 4x = 60-62, and its close affinity with the highly sterile, triploid (2n = 3x = 44-45 hybrid taxon M. × robertsii (M. guttatus × M. luteus, suggests that M. peregrinus may constitute an example of recent allopolyploid speciation.

Hydrogen-bonded intermediates and transition states during spontaneous and acid-catalyzed hydrolysis of the carcinogen (+)-anti-BPDE.

Science.gov (United States)

Palenik, Mark C; Rodriguez, Jorge H

2014-07-07

Understanding mechanisms of (+)-anti-BPDE detoxification is crucial for combating its mutagenic and potent carcinogenic action. However, energetic-structural correlations of reaction intermediates and transition states during detoxification via hydrolysis are poorly understood. To gain mechanistic insight we have computationally characterized intermediate and transition species associated with spontaneous and general-acid catalyzed hydrolysis of (+)-anti-BPDE. We studied the role of cacodylic acid as a proton donor in the rate limiting step. The computed activation energy (ΔG‡) is in agreement with the experimental value for hydrolysis in a sodium cacodylate buffer. Both types of, spontaneous and acid catalyzed, BPDE hydrolysis can proceed through low-entropy hydrogen bonded intermediates prior to formation of transition states whose energies determine reaction activation barriers and rates.

Efectos del forraje diferido como cobertura de invierno en el crecimiento primaveral de las gramíneas tropicales Chloris gayana y Panicum coloratum

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José A. Imaz

2017-01-01

Full Text Available En La Plata, Buenos Aires, Argentina, en un experimento en macetas a aire libre (condiciones de luz y temperatura naturales se evaluó el efecto del forraje diferido como cobertura invernal en 2 gramíneas tropicales C4 (Chloris gayana y Panicum coloratum. Plantas adultas fueron extraídas de un establecimiento ganadero, trasplantadas a macetas en un jardín experimental y después de crecer durante 111 días (2 de Febrero al 23 de Mayo sometidas a los tratamientos: (1 control [sin remoción del forraje diferido de otoño (DF]; y (2 remoción del forraje diferido de otoño (DFR a 15 cm del suelo. Se utilizaron 10 repeticiones por tratamiento y una planta por maceta (unidad experimental. Las plantas fueron cosechadas el 27 de Septiembre (después del invierno y nuevamente en Noviembre para medir la biomasa del rebrote primaveral en los estratos superior (>15 cm e inferior (<15 cm sobre el suelo, láminas, vainas y estolones. Se realizó un análisis alométrico para dilucidar la incidencia del estrés por frio y se registraron la temperatura del aire, la humedad relativa y la ocurrencia de heladas. Las plantas con forraje diferido alcanzaron una mayor biomasa (55‒80% que aquellas con remoción del forraje. Panicum coloratum mostró un ajuste significativo entre la biomasa total y la biomasa de los diferentes estratos para ambos tratamientos, mostrando buena tolerancia al estrés por frio. Por otro lado, C. gayana mostró  falta de ajuste de la biomasa y un mayor estrés por la remoción del forraje, mientras que las plantas sin remoción presentaron menor daño por frío y un mayor ajuste. La cobertura invernal del forraje diferido podría mejorar la productividad y supervivencia de estas especies forrajeras cuando son utilizadas en sistemas pastoriles templados. Estos resultados preliminares deben ser evaluados en condiciones de campo durante un mayor número de años, considerando diferentes estrategias de pastoreo. Palabras clave: Cobertura

Information acquisition and financial intermediation

OpenAIRE

Boyarchenko, Nina

2012-01-01

This paper considers the problem of information acquisition in an intermediated market, where the specialists have access to superior technology for acquiring information. These informational advantages of specialists relative to households lead to disagreement between the two groups, changing the shape of the intermediation-constrained region of the economy and increasing the frequency of periods when the intermediation constraint binds. Acquiring the additional information is, however, cost...

Evidence for close side-chain packing in an early protein folding intermediate previously assumed to be a molten globule.

Science.gov (United States)

Rosen, Laura E; Connell, Katelyn B; Marqusee, Susan

2014-10-14

The molten globule, a conformational ensemble with significant secondary structure but only loosely packed tertiary structure, has been suggested to be a ubiquitous intermediate in protein folding. However, it is difficult to assess the tertiary packing of transiently populated species to evaluate this hypothesis. Escherichia coli RNase H is known to populate an intermediate before the rate-limiting barrier to folding that has long been thought to be a molten globule. We investigated this hypothesis by making mimics of the intermediate that are the ground-state conformation at equilibrium, using two approaches: a truncation to generate a fragment mimic of the intermediate, and selective destabilization of the native state using point mutations. Spectroscopic characterization and the response of the mimics to further mutation are consistent with studies on the transient kinetic intermediate, indicating that they model the early intermediate. Both mimics fold cooperatively and exhibit NMR spectra indicative of a closely packed conformation, in contrast to the hypothesis of molten tertiary packing. This result is important for understanding the nature of the subsequent rate-limiting barrier to folding and has implications for the assumption that many other proteins populate molten globule folding intermediates.

Prairie revegetation of a strip mine in Illinois: fifteen years after establishment

Energy Technology Data Exchange (ETDEWEB)

Corbett, E.A.; Anderson, R.C.; Rodgers, C.S. [Illinois State University, Normal, IL (United States). Dept. of Biological Sciences

1996-12-01

The long-term success of prairie planting on a former strip mine in northeastern Illinois was investigated. The site was reclaimed and planted with prairie species in the 1970s. Total biomass increased over time, largely as a result of an increase in biomass of non-prairie species. Biomass of prairie species remained unchanged because of an increase in Panicum virgatum (switchgrass) offsetting decreases in Sorghastrum nutans (Indian grass).

Fingerprinting taste buds: intermediate filaments and their implication for taste bud formation.

OpenAIRE

Witt, M; Reutter, K; Ganchrow, D; Ganchrow, J R

2000-01-01

Intermediate filaments in taste organs of terrestrial (human and chick) as well as aquatic (Xenopus laevis) species were detected using immunohistochemistry and electron microscopy. During development, the potential importance of the interface between the taste bud primordium and non-gustatory adjacent tissues is evidenced by the distinct immunoreactivity of a subpopulation of taste bud cells for cytokeratins and vimentin. In human foetuses, the selective molecular marker for taste bud primor...

Effect of grazing system and the grass species on the pasture infestation and on the nematode gastrointestinal parasitism in beef cattle Efeito de sistema de pastejo e de espécies forrageiras na contaminação da pastagem e no parasitismo por nematóides gastrintestinais em bovinos de corte

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Ivo Bianchin

2007-12-01

Full Text Available During two years, the infestation of infecting larvae on grazing grass and the level of gastrointestinal nematodes in beef cattle, in the region of the Brazilian Cerrado, were monitored. In the first study, parasitological variables were investigated on pasture of Panicum maximum cv Mombaça, under continuous or rotational grazing, with four (36 resting days and 12 occupation days and ten paddocks (36 resting days and 4 occupation days. In the second study, these variables were evaluated with different forage species (Panicum maximum cv Mombaça, Braquiaria brizantha cv Marandu and Cynodon spp. (Tifton 85, under rotational grazing on eight paddocks (28 resting days and 4 occupation days. In the first study, and only in the first year, the infestation of pasture with infecting larvae was lower (P<0.05 in the rotation system with ten divisions. For the remaining observations of both studies, there were no significant effects of grazing systems and grass species on the fecal egg count and the number of infecting larvae in the pasture. These results indicated that, in the conditions the studies were carried out, the pasture resting for 36 days was insufficient to decrease the EPF and the infestation of pasture.Durante dois anos, acompanhou-se a infestação das pastagens por larvas infectantes e o nível de parasitismo por nematódeos gastrintestinais em bovinos de corte, na região do Cerrado. No primeiro estudo as variáveis parasitológicas foram acompanhadas em pastagens de Panicum maximum cv Mombaça, submetidas ao pastejo continuo e ao rotacionado, com 4 (36 dias de descanso e 12 dias de ocupação e 10 piquetes (36 dias de descanso e 4 dias de ocupação. No segundo estudo, essas variáveis foram avaliadas com diferentes espécies forrageiras (Panicum maximum cv Mombaça, Braquiaria brizantha cv Marandu e Cynodon spp (Tifton 85, sob pastejo rotacionado em 8 piquetes (28 dias de descanso e 4 dias de ocupação. No primeiro estudo, e apenas no

Composição química do capim-Mombaça (Panicum maximum Jacq. cv. Mombaça adubado com diferentes fontes de fósforo sob pastejo = Chemical composition of Mombaça grass (Panicum maximum Jacq. cv. Mombaça fertilized with different phosphorus on grazing

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Fábio Jacobs Dias

2007-01-01

Full Text Available O objetivo foi avaliar a composição química do Panicum maximum Jacq. cv. Mombaça, adubado com 140 kg ha-1 de P2O5 com diferentes fontes de fósforo, sob pastejo, no período de dezembro de 2002 a abril de 2003, com intervalo de coleta a cada 28 dias. Tratamentos: 1- termofosfato magnesiano YoorinÒ; 2-fosfato natural GafsaÒ; 3-superfosfato simples + superfosfato triplo (SS + ST; e 4-testemunha. Os teores de proteína bruta na lâmina foliar (PBf e colmo (PBc, nitrogênio insolúvel em detergente ácido (NIDA, fibra em detergente neutro (FDN, fibra em detergente ácido (FDA, celulose (CEL, hemicelulose (HCEL, lignina (LIG, extrato etéreo (EE, cálcio (Ca, fósforo (P, cinzas e carboidratos não-estruturais (CNE, não foram influenciados pela adubação fosfatada. As variáveis PBc, FDNf, FDNc, LIGf, LIGc, CELf, CELc, NIDAf, EEf, EEc, Caf, Cac, Pf, Pc, CINZAc, CNEc, apresentaram efeito do período de coleta. Não ocorreu diferença nacomposição química da forragem do capim-Mombaça em função das fontes de fósforo utilizadas na adubação da pastagem. As variações qualitativas foram de baixa magnitude.This study aimed to evaluate the chemical composition of Panicum maximum Jacq. cv. Mombaça. Grassland was fertilized with 140 kg ha-1 of P2O5 from different phosphorus sources on grazing, in December, 2002, until April, 2003, with a collection interval of every 28 days. Treatments: 1-YoorinÒ magnesium thermophosphate; 2-GafsaÒ natural phosphate; 3-simple superphosphate + triple superphosphate (SS + TS and 4-control. Leaf (lCP and stem (sCP crude protein, acid detergent fiber nitrogen (ADFN, neutral detergent fiber (NDF, acid detergent fiber (ADF, cellulose (CEL, hemicellulose (HEM, lignin (LIG, ether extract (EE, calcium (Ca, phosphorus (P, ash (A and non-structural carbohydrates (NSC were not influenced by phosphated fertilization. The variables sCP, lNDF, sNDF, sLIG, lLIG, sCEL, lCEL, lADFN, sEE, lEE, lCa, sCa, lP, sP, sA and s

Discourses and Models of Intermediality

OpenAIRE

Schröter, Jens

2011-01-01

In his article "Discourses and Models of Intermediality" Jens Schröter discusses the question as to what relations do different discourses pose between different "media." Schröter identifies four models of discourse: 1) synthetic intermediality: a "fusion" of different media to super-media, a model with roots in the Wagnerian concept of Gesamtkunstwerk with political connotations, 2) formal (or transmedial) intermediality: a concept based on formal structures not "specific" to one medium but ...

Répartition et valorisation des macrophytes envahissantes dans la ...

African Journals Online (AJOL)

SARAH

30 avr. 2016 ... showed that 2 species (Eichhornia crassipes and Panicum maximum) were the most represented. Sorensen ... d'E. crassipes apparaît comme un danger à juguler. (Karim et ... déséquilibre et la diminution voire l'extinction de.

Time-resolved resonance Raman spectroscopy of intermediates of bacteriorhodopsin: The bK(590) intermediate.

Science.gov (United States)

Terner, J; Hsieh, C L; Burns, A R; El-Sayed, M A

1979-07-01

We have combined microbeam and flow techniques with computer subtraction methods to obtain the resonance Raman spectrum of the short lived batho-intermediate (bK(590)) of bacteriorhodopsin. Comparison of the spectra obtained in (1)H(2)O and (2)H(2)O, as well as the fact that the bK(590) intermediate shows large optical red shifts, suggests that the Schiff base linkage of this intermediate is protonated. The fingerprint region of the spectrum of bK(590), sensitive to the isomeric configuration of the retinal chromophore, does not resemble the corresponding region of the parent bR(570) form. The resonance Raman spectrum of bK(590) as well as the spectra of all of the other main intermediates in the photoreaction cycle of bacteriorhodopsin are discussed and compared with resonance Raman spectra of published model compounds.

Complete subunit structure of the Clostridium botulinum type D toxin complex via intermediate assembly with nontoxic components.

Science.gov (United States)

Mutoh, Shingo; Kouguchi, Hirokazu; Sagane, Yoshimasa; Suzuki, Tomonori; Hasegawa, Kimiko; Watanabe, Toshihiro; Ohyama, Tohru

2003-09-23

Clostridium botulinum serotype D strains usually produce two types of stable toxin complex (TC), namely, the 300 kDa M (M-TC) and the 660 kDa L (L-TC) toxin complexes. We previously proposed assembly pathways for both TCs [Kouguchi, H., et al. (2002) J. Biol. Chem. 277, 2650-2656]: M-TC is composed by association of neurotoxin (NT) and nontoxic nonhemagglutinin (NTNHA); conjugation of M-TC with three auxiliary types of hemagglutinin subcomponents (HA-33, HA-17, and HA-70) leads to the formation of L-TC. In this study, we found three TC species, 410, 540, and 610 kDa TC species, in the culture supernatant of type D strain 4947. The 540 and 610 kDa TC species displayed banding patterns on SDS-PAGE similar to that of L-TC but with less staining intensity of the HA-33 and HA-17 bands than those of L-TC, indicating that these are intermediate species in the pathway to L-TC assembly. In contrast, the 410 kDa TC species consisted of M-TC and two molecules of HA-70. All of the TC species, except L-TC, demonstrated no hemagglutination activity. When the intermediate TC species were mixed with an isolated HA-33/17 complex, every TC species converted to 650 kDa L-TC with full hemagglutination activity and had the same molecular composition of L-TC. On the basis of titration analysis with the HA-33/17 complex, the stoichiometry of the HA-33/17 complex molecules in the L-TC, 610 kDa, and 540 kDa TC species was estimated as 4, 3, and 2, respectively. In conclusion, the complete subunit composition of mature L-TC is deduced to be a dodecamer assembled by a single NT, a single NTNHA, two HA-70, four HA-33, and four HA-17 molecules.

Role of Intermediate Filaments in Vesicular Traffic

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Azzurra Margiotta

2016-04-01

Full Text Available Intermediate filaments are an important component of the cellular cytoskeleton. The first established role attributed to intermediate filaments was the mechanical support to cells. However, it is now clear that intermediate filaments have many different roles affecting a variety of other biological functions, such as the organization of microtubules and microfilaments, the regulation of nuclear structure and activity, the control of cell cycle and the regulation of signal transduction pathways. Furthermore, a number of intermediate filament proteins have been involved in the acquisition of tumorigenic properties. Over the last years, a strong involvement of intermediate filament proteins in the regulation of several aspects of intracellular trafficking has strongly emerged. Here, we review the functions of intermediate filaments proteins focusing mainly on the recent knowledge gained from the discovery that intermediate filaments associate with key proteins of the vesicular membrane transport machinery. In particular, we analyze the current understanding of the contribution of intermediate filaments to the endocytic pathway.

Intermediality: Bridge to Critical Media Literacy.

Science.gov (United States)

Pailliotet, Ann Watts; Semali, Ladislaus; Rodenberg, Rita K.; Giles, Jackie K.; Macaul, Sherry L.

2000-01-01

Defines "intermediality" as the ability to critically read and write with and across varied symbol systems. Relates it to critical media literacy. Offers rationales for teaching critical media literacy in general, and intermedial instruction in particular. Identifies seven guiding intermedial elements: theory, texts, processes, contexts,…

Evaluation of radiation use efficiency and its relationship with dry matter accumulation in three millet species

Directory of Open Access Journals (Sweden)

behnam kamkar

2009-06-01

Full Text Available A factorial arrangement of three millets species (Panicum miliaceum, Pennisetum glaucum, and Setaria italica and two sowing dates with three replications were used in a completely randomized design to evaluate the radiation use efficiency and its relationship with dry matter accumulation. Leaf area index was used in daily intervals to calculate daily intercepted radiation. Light extinction coefficient was calculated as the slope of regression line between log transformed fraction of intercepted radiation and leaf area index during growing season. Radiation use efficiency was calculated as the slope of linear regression between cumulative intercepted radiation and cumulative biomass during growing season. Results showed that light extinction coefficient and radiation use efficiency for proso, pearl and foxtail millets were 0.75, 0.66, 0.57 and 1.43, 1.83, 1.74 g/MJ in terms of total radiation, respectively. Differences in biomass production were not significant between proso and pearl millets. Proso millet had higher intercepted radiation, but lower radiation use efficiency in comparison with pearl millet. Foxtail millet had lower intercepted radiation than proso and pearl millets, but its radiation use efficiency was higher than pearl millet. Total biomass of foxtail millet was lower than other species. Results indicated that proso and pearl millets can produce more biomass than foxtail millet.

Vascular flora of the Upper Paraná River floodplain Flora vascular da planície de inundação do Alto Rio Paraná

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MC. Souza

2009-06-01

Full Text Available The purpose of this study was to update the floristic inventory found in the Upper Paraná River floodplain. Floristic surveys were performed from February 2000 through March 2008, as part of the Brazilian Long-Term Ecological Research Program (PELD/CNPq -Site 6. The material collected was identified from 774 species, 442 genera, and 116 families. The ten families with high species richness were Leguminosae, Poaceae, Rubiaceae, Asteraceae, Euphorbiaceae, Myrtaceae, Cyperaceae, Solanaceae, Sapindaceae, and Orchidaceae, which contributed to 46.1% of the total number of species. Genera with high richness were Solanum, Cyperus, Panicum, Eugenia, Tillandsia, Serjania, Casearia, and Polygonum, which together contributed to 10.2% of the total number of species. These data, combined with information published in 1997, recorded 955 species, 575 genera, and 128 families. These organisms were from several riparian environments and were distributed as herbs, shrubs, trees, climbers and epiphytes. Panicum maximum, Pennisetum purpureum, Ricinus communis, and Urochloa decumbens are considered weeds due to the wide distributions determined for these species. The results presented herein suggest the need to further investigate the control of these potential weed species.Com o objetivo de ampliar os conhecimentos sobre a flora da planície de inundação do Alto Rio Paraná, foram conduzidos inventários florísticos no período de fevereiro de 2000 a março de 2008, incluídos no Programa Brasileiro de Pesquisas Ecológicas de Longa Duração (PELD/CNPq - Sítio 6. O material coletado foi identificado em 774 espécies, 442 gêneros e 116 famílias. As dez famílias de maior riqueza de espécies foram Leguminosae, Poaceae, Rubiaceae, Asteraceae, Euphorbiaceae, Myrtaceae, Cyperaceae, Solanaceae, Sapindaceae e Orchidaceae, que juntas reuniram 46,1% do total do número de espécies. Os gêneros com maior riqueza de espécies foram Solanum, Cyperus, Panicum, Eugenia

Effects of processing phases on the quality of massai grass seeds

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Lilian Faria de Melo

Full Text Available ABSTRACT Massai grass is an important tropical forage grass. The harvested seeds upon being received by the company, are found to be contaminated with impurities which are removable by processing machines. This procedure is necessary to produce seeds of a quality level within standards established for commercialization and sowing purposes. The objective of this project was to evaluate the effects of processing phases on the physical and physiological quality of massai grass (Panicum maximum x P. infestum, cv. Massai seeds for commercialization purposes. Seeds were sampled before processing and after leaving the air and screen machine (upper and intermediary screens and bottom; first gravity table (drift, upper and intermediate spouts; treating machine; and second gravity table (upper, intermediate, and lower spouts. Seeds were evaluated as to water content, physical (purity and 1,000 seeds weight and physiological quality (germination, first count of germination, seedling vigor classification, accelerated aging, seedling emergence in the field, speed of emergence index, and primary root length, shoot length. Massai grass seeds had their physical and physiological qualities improved when they were processed by an air and screen machine and a gravity table. Seeds from the intermediate discharge spout of the first gravity table, after going through the air and screen machine, are those of with highest physiological potential. The seeds of this species do not need to be processed to fit the germination and purity standards when the national market is the goal.

Cambios en la estructura, la población y la composición de 19 accesiones de Panicum maximum sometidas a pastoreo CIAT-184 Changes in the structure, population and composition of 19 Panicum maximum accessions under grazing conditions

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R Machado

2012-06-01

Full Text Available Este trabajo tuvo como objetivo caracterizar los cambios y la tendencia de indicadores relacionados con la estructura, la población y la composición en 19 accesiones de Panicum maximum cuando fueron sometidas a condiciones de pastoreo simulado. Las rotaciones se hicieron cada 32-40 días en el periodo lluvioso y 60-70 días en el poco lluvioso, con intensidad de pastoreo de 80-135 UGM/ha/día (los dos primeros años y 120-160 UGM/ha/día (tercer año. Se utilizó un diseño de bloques al azar con tres repeticiones. Aunque en todos los tratamientos disminuyó la relación vástagos vivos/vástagos muertos, este cociente fue superior a uno, por lo que el ritmo de sustitución de vástagos fue favorable. En el 84,2% de los tratamientos se incrementó el número de macollas con relación a el estatus inicial. El porcentaje de arvenses aumentó con las rotaciones, pero ninguno de los tratamientos alcanzó un estado de deterioro avanzado. En este indicador se destacaron los tipos gigantes CIH-13, SIH-697, CIH-3, CC-1146 y SIH-10, con valores que variaron entre 4,6 y 14,1%, así como los tipos medianos CIH-15 y Tardío pequeño, con 10 y 12,3%, respectivamente. Se concluye que el germoplasma evaluado mostró valores adecuados, en función de los indicadores relacionados con la estructura de la macolla, la población y el porcentaje de invasión de las especies arvenses, aunque se identificó un alto contraste entre los tipos gigantes y medianos y dentro de estos grupos. Se sugiere analizar el resto de los indicadores productivos y con ello determinar los tipos más sobresalientes, sobre la base de los resultados en todos los indicadores incluidos.The objective of this work was to characterize the changes and trend of indicators related to the structure, population and composition in 19 Panicum maximum accessions under simulated grazing conditions. The rotations took place every 32-40 days in the rainy season and 60-70 days in the dry season, with

Exploring the chemical kinetics of partially oxidized intermediates by combining experiments, theory, and kinetic modeling.

Science.gov (United States)

Hoyermann, Karlheinz; Mauß, Fabian; Olzmann, Matthias; Welz, Oliver; Zeuch, Thomas

2017-07-19

Partially oxidized intermediates play a central role in combustion and atmospheric chemistry. In this perspective, we focus on the chemical kinetics of alkoxy radicals, peroxy radicals, and Criegee intermediates, which are key species in both combustion and atmospheric environments. These reactive intermediates feature a broad spectrum of chemical diversity. Their reactivity is central to our understanding of how volatile organic compounds are degraded in the atmosphere and converted into secondary organic aerosol. Moreover, they sensitively determine ignition timing in internal combustion engines. The intention of this perspective article is to provide the reader with information about the general mechanisms of reactions initiated by addition of atomic and molecular oxygen to alkyl radicals and ozone to alkenes. We will focus on critical branching points in the subsequent reaction mechanisms and discuss them from a consistent point of view. As a first example of our integrated approach, we will show how experiment, theory, and kinetic modeling have been successfully combined in the first infrared detection of Criegee intermediates during the gas phase ozonolysis. As a second example, we will examine the ignition timing of n-heptane/air mixtures at low and intermediate temperatures. Here, we present a reduced, fuel size independent kinetic model of the complex chemistry initiated by peroxy radicals that has been successfully applied to simulate standard n-heptane combustion experiments.

Intertidal soft-sediment community does not respond to disturbance as postulated by the intermediate disturbance hypothesis

Science.gov (United States)

Gerwing, Travis G.; Allen Gerwing, Alyssa M.; Macdonald, Tara; Cox, Kieran; Juanes, Francis; Dudas, Sarah E.

2017-11-01

The Intermediate Disturbance Hypothesis (IDH) predicts that disturbances of an intermediate frequency or intensity will maximize community biodiversity/richness. Once almost universally accepted, controversy now surrounds this hypothesis, and there have even been calls for its abandonment. Therefore, we experimentally evaluated if an infaunal community along the north coast of British Columbia, Canada, would respond to disturbances as predicted by the IDH. The characteristics of this soft-sediment intertidal mudflat (productivity, species pool, population growth rate) maximized our chances of finding evidence to support the IDH. More specifically, we tested if intermediate severities and frequencies of disturbance maximized infaunal community richness by mechanically disturbing sediment, and varying the intensity (0%, 25%, 50%, 75%, and 100% of the surface area of a plot disturbed) and frequency of sediment disturbance (never, once, twice, and every week during a four week period). No effect of frequency or intensity of sediment disturbance on community richness was observed. Further, none of our experimental treatments were statistically different than the controls. This is likely due to the subtle difference between successional stages in this soft-sediment habitat (difference of less than one taxa between treatments). Therefore, in habitats whose productivity, regional species pool, and population growth rates would otherwise suggest a response to disturbances as predicted by the IDH, minor differences between successional stages may result in richness patterns that deviate from those predicted by the IDH.

Electron-atom scattering at intermediate energies

International Nuclear Information System (INIS)

Kingston, A.E.; Walters, H.R.J.

1982-01-01

The problems of intermediate energy scattering are approached from the low and high energy ends. At low intermediate energies difficulties associated with the use of pseudostates and correlation terms are discussed, special consideration being given to nonphysical pseudoresonances. Perturbation methods appropriate to high intermediate energies are described and attempts to extend these high energy approximations down to low intermediate energies are studied. It is shown how the importance of electron exchange effects develops with decreasing energy. The problem of assessing the 'effective completeness' of pseudostate sets at intermediate energies is mentioned and an instructive analysis of a 2p pseudostate approximation to elastic e - -H scattering is given. It is suggested that at low energies the Pauli Exclusion Principle can act to hide short range defects in pseudostate approximations. (author)

The intermediate state in Patd

African Journals Online (AJOL)

) Jesus had assumed. (concerning the 'intermediate state') as existing, anything which does not exist. Three basic things about the intermediate state emerge from the parable: (a) Jesus recognizes that at the moment of death, in ipso articulo.

Higher order antibunching in intermediate states

International Nuclear Information System (INIS)

Verma, Amit; Sharma, Navneet K.; Pathak, Anirban

2008-01-01

Since the introduction of binomial state as an intermediate state, different intermediate states have been proposed. Different nonclassical effects have also been reported in these intermediate states. But till now higher order antibunching is predicted in only one type of intermediate state, which is known as shadowed negative binomial state. Recently we have shown that the higher order antibunching is not a rare phenomenon [P. Gupta, P. Pandey, A. Pathak, J. Phys. B 39 (2006) 1137]. To establish our earlier claim further, here we have shown that the higher order antibunching can be seen in different intermediate states, such as binomial state, reciprocal binomial state, hypergeometric state, generalized binomial state, negative binomial state and photon added coherent state. We have studied the possibility of observing the higher order subpoissonian photon statistics in different limits of intermediate states. The effects of different control parameters on the depth of non classicality have also been studied in this connection and it has been shown that the depth of nonclassicality can be tuned by controlling various physical parameters

Chemical intermediate detection following corona discharge on volatile organic compounds: general method using molecular beam techniques

International Nuclear Information System (INIS)

He Luning; Sulkes, Mark

2011-01-01

Nonthermal plasma (NTP)-based treatments of volatile organic compounds (VOCs) have potential for effective environmental remediation. Theory and experiment that consider the basic science pertaining to discharge events have helped improve NTP remediation outcomes. If direct information on early post-discharge chemical intermediates were also available, it would likely lead to additional improvement in NTP remediation outcomes. To this point, however, experiments yielding direct information on post-NTP VOC intermediates have been limited. An approach using supersonic expansion molecular beam methods offers general promise for detection of post-discharge VOC intermediates. To illustrate the potential utility of these methods, we present mass spectra showing the growth of early products formed when pulsed corona discharges were carried out on toluene in He and then in He with added O 2 . Good general detection of neutral post-discharge species was obtained using 800 nm 150 fs photoionization pulses.

[Therapy of intermediate uveitis].

Science.gov (United States)

Doycheva, D; Deuter, C; Zierhut, M

2014-12-01

Intermediate uveitis is a form of intraocular inflammation in which the vitreous body is the major site of inflammation. Intermediate uveitis is primarily treated medicinally and systemic corticosteroids are the mainstay of therapy. When recurrence of uveitis or side effects occur during corticosteroid therapy an immunosuppressive treatment is required. Cyclosporine A is the only immunosuppressive agent that is approved for therapy of uveitis in Germany; however, other immunosuppressive drugs have also been shown to be effective and well-tolerated in patients with intermediate uveitis. In severe therapy-refractory cases when conventional immunosuppressive therapy has failed, biologics can be used. In patients with unilateral uveitis or when the systemic therapy is contraindicated because of side effects, an intravitreal steroid treatment can be carried out. In certain cases a vitrectomy may be used.

Role of bioinoculants and organic fertilizers in fodder production and quality of leguminous tree species.

Science.gov (United States)

Mishra, Seema; Sharma, Satyawati; Vasudevan, Padma

2011-01-01

The comparative effect of dual inoculation of native N fixer (Rhizobium) and AM fungi consortia with different organic fertilizers (vermicompost and farm yard manure) on fodder production and quality of two leguminous tree species (Leucaena leucocephala (Lam) de. Wit. and Sesbania sesban (L.) Merr.) in silvopastoral system and their impact on the fodder production of un-inoculated Panicum maximum Jacq. under cut and carry system. After three years of plantation maximum tree survival was in L. leucocephala in all the treatments in comparison to S. sesban while fodder production was more in S. sesban for initial two years and in third year it accelerated in L. leucocephala. Dual inoculation with vermicompost significantly improved fodder production, fodder quality and rhizosphere microflora in L. leucocephala but in S. sesban dual inoculation was at par with single inoculation of N fixer, AM fungi and control (without inoculation). The grass production was higher with L. leucocephala for two years while in third year it was more with S. sesban. The association of Rhizobium with AM fungi in L. leucocephala was better than in S. sesban.

Répartition et valorisation des macrophytes envahissantes dans la ...

African Journals Online (AJOL)

... of Littoral (Cameroon) threatened by invasive macrophytes, an ecological study highlighting the ... The floristic inventory showed that 2 species (Eichhornia crassipes and Panicum ... This plant can thus be used for biogas or compost production ... Tanzania (19); Togo (1); Tunisia (2); Uganda (12); Zambia (2); Zimbabwe (12).

Chemokines in teleost fish species.

Science.gov (United States)

Alejo, Alí; Tafalla, Carolina

2011-12-01

Chemokines are chemoattractant cytokines defined by the presence of four conserved cysteine residues which in mammals can be divided into four subfamilies depending on the arrangement of the first two conserved cysteines in their sequence: CXC (α), CC (β), C and CX(3)C classes. Evolutionarily, fish can be considered as an intermediate step between species which possess only innate immunity (invertebrates) and species with a fully developed acquired immune network such as mammals. Therefore, the functionality of their different immune cell types and molecules is sometimes also intermediate between innate and acquired responses. The first chemokine gene identified in a teleost was a rainbow trout (Oncorhynchus mykiss) chemokine designated as CK1 in 1998. Since then, many different chemokine genes have been identified in several fish species, but their role in homeostasis and immune response remains largely unknown. Extensive genomic duplication events and the fact that chemokines evolve more quickly than other immune genes, make it very difficult to establish true orthologues between fish and mammalian chemokines that would help us with the ascription of immune roles. In this review, we describe the current state of knowledge of chemokine biology in teleost fish, focusing mainly on which genes have been identified so far and highlighting the most important aspects of their expression regulation, due to the great lack of functional information available for them. As the number of chemokine genes begins to close down for some teleost species, there is an important need for functional assays that may elucidate the role of each of these molecules within the fish immune response. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nitrate denitrification with nitrite or nitrous oxide as intermediate products: Stoichiometry, kinetics and dynamics of stable isotope signatures.

Science.gov (United States)

Vavilin, V A; Rytov, S V

2015-09-01

A kinetic analysis of nitrate denitrification by a single or two species of denitrifying bacteria with glucose or ethanol as a carbon source and nitrite or nitrous oxide as intermediate products was performed using experimental data published earlier (Menyailo and Hungate, 2006; Vidal-Gavilan et al., 2013). Modified Monod kinetics was used in the dynamic biological model. The special equations were added to the common dynamic biological model to describe how isotopic fractionation between N species changes. In contrast to the generally assumed first-order kinetics, in this paper, the traditional Rayleigh equation describing stable nitrogen and oxygen isotope fractionation in nitrate was derived from the dynamic isotopic equations for any type of kinetics. In accordance with the model, in Vidal-Gavilan's experiments, the maximum specific rate of nitrate reduction was proved to be less for ethanol compared to glucose. Conversely, the maximum specific rate of nitrite reduction was proved to be much less for glucose compared to ethanol. Thus, the intermediate nitrite concentration was negligible for the ethanol experiment, while it was significant for the glucose experiment. In Menyailo's and Hungate's experiments, the low value of maximum specific rate of nitrous oxide reduction gives high intermediate value of nitrous oxide concentration. The model showed that the dynamics of nitrogen and oxygen isotope signatures are responding to the biological dynamics. Two microbial species instead of single denitrifying bacteria are proved to be more adequate to describe the total process of nitrate denitrification to dinitrogen. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evidence for hybridization and introgression within a species-rich oak (Quercus spp. community

Directory of Open Access Journals (Sweden)

Finkeldey Reiner

2007-11-01

Full Text Available Abstract Background Analysis of interspecific gene flow is crucial for the understanding of speciation processes and maintenance of species integrity. Oaks (genus Quercus, Fagaceae are among the model species for the study of hybridization. Natural co-occurrence of four closely related oak species is a very rare case in the temperate forests of Europe. We used both morphological characters and genetic markers to characterize hybridization in a natural community situated in west-central Romania and which consists of Quercus robur, Q. petraea, Q. pubescens, and Q. frainetto, respectively. Results On the basis of pubescence and leaf morphological characters ~94% of the sampled individuals were assigned to pure species. Only 16 (~6% individual trees exhibited intermediate morphologies or a combination of characters of different species. Four chloroplast DNA haplotypes were identified in the study area. The distribution of haplotypes within the white oak complex showed substantial differences among species. However, the most common haplotypes were present in all four species. Furthermore, based on a set of 7 isozyme and 6 microsatellite markers and using a Bayesian admixture analysis without any a priori information on morphology we found that four genetic clusters best fit the data. There was a very good correspondence of each species with one of the inferred genetic clusters. The estimated introgression level varied markedly between pairs of species ranging from 1.7% between Q. robur and Q. frainetto to 16.2% between Q. pubescens and Q. frainetto. Only nine individuals (3.4% appeared to be first-generation hybrids. Conclusion Our data indicate that natural hybridization has occurred at relatively low rates. The different levels of gene flow among species might be explained by differences in flowering time and spatial position within the stand. In addition, a partial congruence between phenotypically and genetically intermediate individuals was

Efeito inibidor dos extratos hidroalcóolicos de coberturas mortas sobre a germinação de sementes de cenoura e alface Inhibitory effects of hydroalcoholic extracts of five plant species used as mulches on germination of lettuce and carrot seeds

Directory of Open Access Journals (Sweden)

Cláudio L. M. de Souza

1999-08-01

Full Text Available O objetivo deste trabalho foi obter a prospecção fitoquímica e avaliar o efeito inibitório dos extratos hidroalcóolicos de capim-gordura (Melinis minutiflora, capim-jaraguá (Hyparrhenia rufa, capim-colonião (Panicum maximum, mucuna (Mucuna aterrima e serrapilheira de bambu (Bambuza spp., sobre a germinação de sementes de alface e cenoura. O teste de germinação foi conduzido sobre papel umedecido com extrato das espécies citadas diluídos em 25, 50, 75 e 100 % (v/v, e água destilada. Avaliou-se a porcentagem de final e o índice de velocidade de germinação. O índice de velocidade de germinação e a porcentagem de germinação de sementes de cenoura e alface, reduziram significativamente nas diluições de 50 a 100 % (v/v em relação as demais diluições e ao controle. O extrato de mucuna apresentou significativamente maior efeito inibidor em comparação com os demais extratos testados, principalmente sobre a germinação de sementes de alface. A prospecção fitoquímica indicou a presença de classes de substâncias com potencial alelopático.Studies were undertaken to evaluate the inhibitory activity of hydroalcoholic extracts from dry mass of plant species used as mulches: Melinis minutiflora, Hyparrhenia rufa, Panicum maximum, Mucuna aterrima and bamboo leaves (Bambuza spp.. The inhibitory activity was measured on germination tests of lettuce and carrot seeds. Five extract concentrations of each species were used: 0, 25, 50, 75 and 100 % (v/v. The rate of speed germination and percentage of germination of both species decreased significatly in function of the extract concentrations in the range from 50 to 100 % (v/v. Mucuna aterrima extract was significatly more inibitory than the other extracts, mainly for lettuce seeds. Bioassays with extracts showed the presence of several groups of alleopathic compounds.

Effect of Intermediate Hosts on Emerging Zoonoses.

Science.gov (United States)

Cui, Jing-An; Chen, Fangyuan; Fan, Shengjie

2017-08-01

Most emerging zoonotic pathogens originate from animals. They can directly infect humans through natural reservoirs or indirectly through intermediate hosts. As a bridge, an intermediate host plays different roles in the transmission of zoonotic pathogens. In this study, we present three types of pathogen transmission to evaluate the effect of intermediate hosts on emerging zoonotic diseases in human epidemics. These types are identified as follows: TYPE 1, pathogen transmission without an intermediate host for comparison; TYPE 2, pathogen transmission with an intermediate host as an amplifier; and TYPE 3, pathogen transmission with an intermediate host as a vessel for genetic variation. In addition, we established three mathematical models to elucidate the mechanisms underlying zoonotic disease transmission according to these three types. Stability analysis indicated that the existence of intermediate hosts increased the difficulty of controlling zoonotic diseases because of more difficult conditions to satisfy for the disease to die out. The human epidemic would die out under the following conditions: TYPE 1: [Formula: see text] and [Formula: see text]; TYPE 2: [Formula: see text], [Formula: see text], and [Formula: see text]; and TYPE 3: [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] Simulation with similar parameters demonstrated that intermediate hosts could change the peak time and number of infected humans during a human epidemic; intermediate hosts also exerted different effects on controlling the prevalence of a human epidemic with natural reservoirs in different periods, which is important in addressing problems in public health. Monitoring and controlling the number of natural reservoirs and intermediate hosts at the right time would successfully manage and prevent the prevalence of emerging zoonoses in humans.

Intermediate structure and threshold phenomena

International Nuclear Information System (INIS)

Hategan, Cornel

2004-01-01

The Intermediate Structure, evidenced through microstructures of the neutron strength function, is reflected in open reaction channels as fluctuations in excitation function of nuclear threshold effects. The intermediate state supporting both neutron strength function and nuclear threshold effect is a micro-giant neutron threshold state. (author)

Intermediate algebra & analytic geometry

CERN Document Server

Gondin, William R

1967-01-01

Intermediate Algebra & Analytic Geometry Made Simple focuses on the principles, processes, calculations, and methodologies involved in intermediate algebra and analytic geometry. The publication first offers information on linear equations in two unknowns and variables, functions, and graphs. Discussions focus on graphic interpretations, explicit and implicit functions, first quadrant graphs, variables and functions, determinate and indeterminate systems, independent and dependent equations, and defective and redundant systems. The text then examines quadratic equations in one variable, system

Nest survival modelling using a multi-species approach in forests managed for timber and biofuel feedstock

Science.gov (United States)

Loman, Zachary G.; Monroe, Adrian; Riffell, Samuel K.; Miller, Darren A.; Vilella, Francisco; Wheat, Bradley R.; Rush, Scott A.; Martin, James A.

2018-01-01

Switchgrass (Panicum virgatum) intercropping is a novel forest management practice for biomass production intended to generate cellulosic feedstocks within intensively managed loblolly pine‐dominated landscapes. These pine plantations are important for early‐successional bird species, as short rotation times continually maintain early‐successional habitat. We tested the efficacy of using community models compared to individual surrogate species models in understanding influences on nest survival. We analysed nest data to test for differences in habitat use for 14 bird species in plots managed for switchgrass intercropping and controls within loblolly pine (Pinus taeda) plantations in Mississippi, USA.We adapted hierarchical models using hyper‐parameters to incorporate information from both common and rare species to understand community‐level nest survival. This approach incorporates rare species that are often discarded due to low sample sizes, but can inform community‐level demographic parameter estimates. We illustrate use of this approach in generating both species‐level and community‐wide estimates of daily survival rates for songbird nests. We were able to include rare species with low sample size (minimum n = 5) to inform a hyper‐prior, allowing us to estimate effects of covariates on daily survival at the community level, then compare this with a single‐species approach using surrogate species. Using single‐species models, we were unable to generate estimates below a sample size of 21 nests per species.Community model species‐level survival and parameter estimates were similar to those generated by five single‐species models, with improved precision in community model parameters.Covariates of nest placement indicated that switchgrass at the nest site (<4 m) reduced daily nest survival, although intercropping at the forest stand level increased daily nest survival.Synthesis and applications. Community models represent a viable

Regularities of intermediate adsorption complex relaxation

International Nuclear Information System (INIS)

Manukova, L.A.

1982-01-01

The experimental data, characterizing the regularities of intermediate adsorption complex relaxation in the polycrystalline Mo-N 2 system at 77 K are given. The method of molecular beam has been used in the investigation. The analytical expressions of change regularity in the relaxation process of full and specific rates - of transition from intermediate state into ''non-reversible'', of desorption into the gas phase and accumUlation of the particles in the intermediate state are obtained

FINANCIAL INTERMEDIATION, ENTREPRENEURSHIP AND ECONOMIC GROWTH

OpenAIRE

Wenli Cheng

2007-01-01

This paper presents a simple general equilibrium model of financial intermediation, entrepreneurship and economic growth. In this model, the role of financial intermediation is to pool savings and to lend the pooled funds to an entrepreneur, who in turn invests the funds in a new production technology. The adoption of the new production technology improves individual real income. Thus financial intermediation promotes economic growth through affecting individuals’ saving behaviour and enabl...

Some Intermediate-Level Violin Concertos.

Science.gov (United States)

Abramson, Michael

1997-01-01

Contends that many violin students attempt difficult concertos before they are technically or musically prepared. Identifies a variety of concertos at the intermediate and advanced intermediate-level for students to study and master before attempting the advanced works by Bach and Mozart. Includes concertos by Vivaldi, Leclair, Viotti, Haydn,…

Rare earth elements (REEs): effects on germination and growth of selected crop and native plant species.

Science.gov (United States)

Thomas, Philippe J; Carpenter, David; Boutin, Céline; Allison, Jane E

2014-02-01

The phytotoxicity of rare earth elements (REEs) is still poorly understood. The exposure-response relationships of three native Canadian plant species (common milkweed, Asclepias syriaca L., showy ticktrefoil, Desmodium canadense (L.) DC. and switchgrass, Panicum virgatum L.) and two commonly used crop species (radish, Raphanus sativus L., and tomato, Solanum lycopersicum L.) to the REEs lanthanum (La), yttrium (Y) and cerium (Ce) were tested. In separate experiments, seven to eight doses of each element were added to the soil prior to sowing seeds. Effects of REE dose on germination were established through measures of total percent germination and speed of germination; effects on growth were established through determination of above ground biomass. Ce was also tested at two pH levels and plant tissue analysis was conducted on pooled samples. Effects on germination were mostly observed with Ce at low pH. However, effects on growth were more pronounced, with detectable inhibition concentrations causing 10% and 25% reductions in biomass for the two native forb species (A. syriaca and D. canadense) with all REEs and on all species tested with Ce in both soil pH treatments. Concentration of Ce in aboveground biomass was lower than root Ce content, and followed the dose-response trend. From values measured in natural soils around the world, our results continue to support the notion that REEs are of limited toxicity and not considered extremely hazardous to the environment. However, in areas where REE contamination is likely, the slow accumulation of these elements in the environment could become problematic. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Welding. Performance Objectives. Intermediate Course.

Science.gov (United States)

Vincent, Kenneth

Several intermediate performance objectives and corresponding criterion measures are listed for each of nine terminal objectives for an intermediate welding course. The materials were developed for a 36-week (3 hours daily) course designed to prepare the student for employment in the field of welding. Electric welding and specialized (TIG & MIG)…

Money distribution with intermediation

OpenAIRE

Teles, Caio Augusto Colnago

2013-01-01

This pap er analyzes the distribution of money holdings in a commo dity money search-based mo del with intermediation. Intro ducing heterogeneity of costs to the Kiyotaki e Wright ( 1989 ) mo del, Cavalcanti e Puzzello ( 2010) gives rise to a non-degenerated distribution of money. We extend further this mo del intro ducing intermediation in the trading pro cess. We show that the distribution of money matters for savings decisions. This gives rises to a xed p oint problem for the ...

Search for intermediate vector bosons

International Nuclear Information System (INIS)

Klajn, D.B.; Rubbia, K.; Meer, S.

1983-01-01

Problem of registration and search for intermediate vector bosons is discussed. According to weak-current theory there are three intermediate vector bosons with +1(W + )-1(W - ) and zero (Z 0 ) electric charges. It was suggested to conduct the investigation into particles in 1976 by cline, Rubbia and Makintair using proton-antiproton beams. Major difficulties of the experiment are related to the necessity of formation of sufficient amount of antiparticles and the method of antiproton beam ''cooling'' for the purpose of reduction of its random movements. The stochastic method was suggested by van der Meer in 1968 as one of possible cooling methods. Several large detectors were designed for searching intermediate vector bosons

Validation of intermediate end points in cancer research.

Science.gov (United States)

Schatzkin, A; Freedman, L S; Schiffman, M H; Dawsey, S M

1990-11-21

Investigations using intermediate end points as cancer surrogates are quicker, smaller, and less expensive than studies that use malignancy as the end point. We present a strategy for determining whether a given biomarker is a valid intermediate end point between an exposure and incidence of cancer. Candidate intermediate end points may be selected from case series, ecologic studies, and animal experiments. Prospective cohort and sometimes case-control studies may be used to quantify the intermediate end point-cancer association. The most appropriate measure of this association is the attributable proportion. The intermediate end point is a valid cancer surrogate if the attributable proportion is close to 1.0, but not if it is close to 0. Usually, the attributable proportion is close to neither 1.0 nor 0; in this case, valid surrogacy requires that the intermediate end point mediate an established exposure-cancer relation. This would in turn imply that the exposure effect would vanish if adjusted for the intermediate end point. We discuss the relative advantages of intervention and observational studies for the validation of intermediate end points. This validation strategy also may be applied to intermediate end points for adverse reproductive outcomes and chronic diseases other than cancer.

Evaluation of the relationship of sowing qualities and yielding properties of millet seed (Panicum meliaceum L..

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С. П. Полторецький

2016-07-01

Full Text Available Purpose. Determination and analysis of relationship of sowing qualities and yield properties of millet seed (Panicum meliaceum L. to be formed by the action of predecessors and conditions of mineral nutrition in the context of unstable moistening in the Right-Bank Forest-Steppe zone of Ukraine. Methods. Mathematico-statistical ones (correlation, regression. Results. The use of correlation pleiades method allowed to analyze multifactor relations of sowing qualities and yield properties of millet seed and establish that there was a direct correlation relationship of medium strength (r = 0.52 ± 0.01 between yielding of maternal and millet plants of the first seed progeny. It was found that maternal plants yielding is strongly correlated with laboratory and technological indicators of seed quality that interrelated through integrated quality parameter of seed material (r = 0.56 ± 0.01 and millet output (r = 0.98 ± 0.00. Integrated quality parameter as well as each of the studied laboratory parameters of seed material quality taken separately have a high-level (r = 0.87…0.96 ± 0.00 effect on the formation of grain yield of the first seed progeny plants. Such physical and technological parameters of the quality of maternal plants yield as a content of protein and fat in seed, seed weight, its uniformity can directly, and millet output, thousand-grain weight and hull content – indirectly indicate peculiarities of forming future grain yield of plants of the first seed progeny. Conclusions. The use of the correlation pleiades method allows to analyze objectively the sowing qualities of millet seed and predict the yield properties in the next generation.

Biocatalytic Synthesis of Chiral Pharmaceutical Intermediates

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Ramesh N. Patel

2004-01-01

Full Text Available The production of single enantiomers of drug intermediates has become increasingly important in the pharmaceutical industry. Chiral intermediates and fine chemicals are in high demand from both the pharmaceutical and agrochemical industries for the preparation of bulk drug substances and agricultural products. The enormous potential of microorganisms and enzymes for the transformation of synthetic chemicals with high chemo-, regio- and enantioselectivities has been demonstrated. In this article, biocatalytic processes are described for the synthesis of chiral pharmaceutical intermediates.

Prediction of isotope effects for anticipated intermediate structures in the course of bacterial denitrification

International Nuclear Information System (INIS)

Morgenstern, M.A.; Schowen, R.L.

1989-01-01

Vibrational-analysis methods have been used to estimate the equilibrium 14 N/ 15 N isotope effects to be expected for conversion of nitrite anion to thirteen possible intermediate-state and product-state structures [HONO, NO + , NO, NO - , FeNO, ON * NO 2 , O * NNO 2 , O 2 NNO 2 , ONO * N, O * NON, ONNO, * NNO, N * NO] in the reduction of nitrite ion to nitrous oxide denitrifying bacteria. The results, taken in combination with previous experimental isotope-effect and tracer studies of the Pseudomonas stutzeri and related systems, are consistent with a suggestion that a second nitrite anion enters the enzyme-catalytic cycle at the stage of a nitrosyl-ion intermediate but re-emerges after entry of the reducing electrons; the product nitrous oxide is then formed by disproportionation of enzymically generated hyponitrous acid. The calculations are consistent with contributions, under different experimental conditions, of several different transition states to limiting the rate of the enzymic reaction. These transition states (and the corresponding experimental conditions) are the transition states for N-O fission in the generation of a mononitrogen electrophilic species from nitrite anion (high reductant, high nitrite concentrations), for attack of nitrite on this electrophile (high reductant, low nitrite concentrations) and for electron transfer to a dinitrogen-trioxide-like species (low reductant concentration). (orig.)

Reactions of stabilized Criegee Intermediates

Science.gov (United States)

Vereecken, Luc; Harder, Hartwig; Novelli, Anna

2014-05-01

Carbonyl oxides (Criegee intermediates) were proposed as key intermediates in the gas phase ozonolysis of alkenes in 1975 by Rudolf Criegee. Despite the importance of ozonolysis in atmospheric chemistry, direct observation of these intermediates remained elusive, with only indirect experimental evidence for their role in the oxidation of hydrocarbons, e.g. through scavenging experiments. Direct experimental observation of stabilized CI has only been achieved since 2008. Since then, a concerted effort using experimental and theoretical means is in motion to characterize the chemistry and kinetics of these reactive intermediates. We present the results of theoretical investigations of the chemistry of Criegee intermediates with a series of coreactants which may be of importance in the atmosphere, in experimental setups, or both. This includes the CI+CI cross-reaction, which proceeds with a rate coefficient near the collision limit and can be important in experimental conditions. The CI + alkene reactions show strong dependence of the rate coefficient depending on the coreactants, but is generally found to be rather slow. The CI + ozone reaction is sufficiently fast to occur both in experiment and the free troposphere, and acts as a sink for CI. The reaction of CI with hydroperoxides, ROOH, is complex, and leads both to the formation of oligomers, as to the formation of reactive etheroxides, with a moderately fast rate coefficient. The importance of these reactions is placed in the context of the reaction conditions in different atmospheric environments ranging from unpolluted to highly polluted.

The intermediate endpoint effect in logistic and probit regression

Science.gov (United States)

MacKinnon, DP; Lockwood, CM; Brown, CH; Wang, W; Hoffman, JM

2010-01-01

Background An intermediate endpoint is hypothesized to be in the middle of the causal sequence relating an independent variable to a dependent variable. The intermediate variable is also called a surrogate or mediating variable and the corresponding effect is called the mediated, surrogate endpoint, or intermediate endpoint effect. Clinical studies are often designed to change an intermediate or surrogate endpoint and through this intermediate change influence the ultimate endpoint. In many intermediate endpoint clinical studies the dependent variable is binary, and logistic or probit regression is used. Purpose The purpose of this study is to describe a limitation of a widely used approach to assessing intermediate endpoint effects and to propose an alternative method, based on products of coefficients, that yields more accurate results. Methods The intermediate endpoint model for a binary outcome is described for a true binary outcome and for a dichotomization of a latent continuous outcome. Plots of true values and a simulation study are used to evaluate the different methods. Results Distorted estimates of the intermediate endpoint effect and incorrect conclusions can result from the application of widely used methods to assess the intermediate endpoint effect. The same problem occurs for the proportion of an effect explained by an intermediate endpoint, which has been suggested as a useful measure for identifying intermediate endpoints. A solution to this problem is given based on the relationship between latent variable modeling and logistic or probit regression. Limitations More complicated intermediate variable models are not addressed in the study, although the methods described in the article can be extended to these more complicated models. Conclusions Researchers are encouraged to use an intermediate endpoint method based on the product of regression coefficients. A common method based on difference in coefficient methods can lead to distorted

Rendimiento y calidad de semilla de pasto guinea (Panicum maximum Jacq. cv. Tanzania usando la fitohormona esteroidal cidef-4

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Bertín Maurilio Joaquín Torres

2010-01-01

Full Text Available El objetivo fue evaluar el efecto de la fitohormona esteroidal cidef-4 en el rendimiento y calidad de semilla en Panicum maximum cv. Tanzania. El experimento se realizó durante el 2001 en Tejupilco, Estado de México. Los tratamientos evaluados fueron, T1=testigo, T2=4 mg L-1 de ingrediente activo (i.a. aplicados al inicio de antesis, T3=4 mg L-1 de i.a. aplicados antes del espigamiento e inicio de antesis, T4=8 mg L-1 de i.a. aplicados al inicio de antesis, T5=8 mg L-1 de i.a. aplicados antes del espigamiento e inicio de antesis y T6=12 mg L-1 de i.a. aplicados únicamente al inicio de antesis. Se utilizó un diseño de bloques al azar, con tres repeticiones. Se evaluó el rendimiento de semilla total (RST, rendimiento de semilla pura (RSP, número de panículas m-2, longitud de panícula, semillas producidas y cosechadas por panícula, peso de 1,000 semillas y germinación. Se detectaron diferencias (P0.05 entre tratamientos. Se concluye que la fitohormona esteroidal cidef-4 incrementó el rendimiento de semilla de P. maximum cv. tanzania, independientemente de la concentración y momento de aplicación. La calidad de la semilla, no fue afectada por ninguno de los tratamientos evaluados.

The phylogeny and life cycle of two species of Profilicollis (Acanthocephala: Polymorphidae) in marine hosts off the Pacific coast of Chile.

Science.gov (United States)

Rodríguez, S M; D'Elía, G; Valdivia, N

2017-09-01

Resolving complex life cycles of parasites is a major goal of parasitological research. The aim of this study was to analyse the life cycle of two species of the genus Profilicollis, the taxonomy of which is still unstable and life cycles unclear. We extracted individuals of Profilicollis from two species of crustaceans (intermediate hosts) and four species of seagulls (definitive hosts) from sandy-shore and estuarine habitats along the south-east Pacific coast of Chile. Mitochondrial DNA analyses showed that two species of Profilicollis infected intermediate hosts from segregated habitats: while P. altmani larvae infected exclusively molecrabs of the genus Emerita from fully marine habitats, P. antarcticus larvae infected the crab Hemigrapsus crenulatus from estuarine habitats. Moreover, P. altmani completed its life cycle in four seagulls, Chroicocephalus maculipennis, Leucopheus pipixcan, Larus modestus and L. dominicanus, while P. antarcticus, on the other hand, completed its life cycle in the kelp gull L. dominicanus. Accordingly, our results show that two congeneric parasites use different and spatially segregated species as intermediate hosts, and both are capable of infecting one species of definitive hosts. As such, our analyses allow us to shed light on a complex interaction network.

Effect of acanthocephalan parasites on hiding behaviour in two species of shore crabs.

Science.gov (United States)

Latham, A D M; Poulin, R

2002-12-01

The effect of acanthocephalan parasites (Profilicollis spp.) on the hiding behaviour during low tide of two species of shore crabs (intermediate hosts), Macrophthalmus hirtipes (Brachyura: Ocypodidae) and Hemigrapsus crenulatus (Brachyura: Grapsidae), was examined at Blueskin Bay, South Island, New Zealand. Exposed M. hirtipes were found to have significantly higher infection levels than did hidden conspecifics. This pattern was not observed for H. crenulatus. Mean cystacanth numbers were found to be considerably higher in M. hirtipes than H. crenulatus. Crabs exposed at low tide are at a greater risk of predation by definitive shorebird hosts than are hidden conspecifics. Preferential manipulation of one intermediate host species over another could influence diversity within ecosystems.

Descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham: II. Influencia de los factores climáticos Litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham: II. Influence of climatic factors

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Saray Sánchez

2009-12-01

Full Text Available Con el objetivo de determinar la descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala y su relación con algunos factores del clima, se realizó este experimento en la EEPF «Indio Hatuey». La descomposición de la hojarasca se determinó como la pérdida de biomasa a través del tiempo, con relación al peso inicial. Para el estudio de la dinámica de la descomposición se utilizó el método de bolsas de hojarasca (litter bags; se registró diariamente el comportamiento de la temperatura media, la humedad relativa, la precipitación y los días con lluvias, en la estación metereológica situada a 1 km del área experimental. Se utilizó el análisis de correlación y regresión para conocer la interrelación entre las variables y los modelos de mejor ajuste. Se consideró, como variables independientes, los factores climáticos estudiados, y como variable dependiente el porcentaje de biomasa perdida. De forma general, los resultados demostraron que el comportamiento de la descomposición de la hojarasca, tanto en la guinea como en la leucaena, estuvo relacionado con los factores climáticos que prevalecieron durante el período experimental y, por tanto, es posible explicar este proceso en ambos pastizales a partir de la acción conjunta de la temperatura, la humedad relativa y la precipitación.With the objective of determining the litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala and its relationship to some climate factors, this trial was conducted at the EEPF «Indio Hatuey». Litter decomposition was determined as the loss of biomass through time, with regards to initial weight. For studying the decomposition dynamics the method of litter bags was used; the performance of mean temperature, relative humidity, rainfall and days with rain, was daily recorded at the meteorological station located 1 km away from the experimental area. . The

Gravity with Intermediate Goods Trade

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Sujin Jang

2017-12-01

Full Text Available This paper derives the gravity equation with intermediate goods trade. We extend a standard monopolistic competition model to incorporate intermediate goods trade, and show that the gravity equation with intermediates trade is identical to the one without it except in that gross output should be used as the output measure instead of value added. We also show that the output elasticity of trade is significantly underestimated when value added is used as the output measure. This implies that with the conventional gravity equation, the contribution of output growth can be substantially underestimated and the role of trade costs reduction can be exaggerated in explaining trade expansion, as we demonstrate for the case of Korea's trade growth between 1995 and 2007.

The South-American distribution and southernmost record of Biomphalaria peregrina—a potential intermediate host of schistosomiasis

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Alejandra Rumi

2017-05-01

Full Text Available Schistosomiasis remains a major parasitic disease, endemic in large parts of South America. Five neotropical species of Biomphalaria have been found to act as intermediate hosts of Schistosoma mansoni in natural populations, while others have been shown to be susceptible in experimental infections, although not found infected in the field. Among these potential intermediate hosts, Biomphalaria peregrina represents the most widespread species in South America, with confirmed occurrence records from Venezuela to northern Patagonia. In this study, we report the southernmost record for the species at the Pinturas River, in southern Patagonia, which finding implies a southward reassessment of the limit for the known species of this genus. The identities of the individuals from this population were confirmed through morphological examination, and by means of two mitochondrial genes, cytochrome oxidase subunit I (COI and 16S-rRNA. With both markers, phylogenetic analyses were conducted in order to compare the genetic background of individuals from the Pinturas River with previously genetically characterized strains of B. peregrina from various South-American locations. In addition, we produced a potential distribution model of B. peregrina in South America and identified the environmental variables that best predict that distribution. The model was estimated through a maximum entropy algorithm and run with occurrence points obtained from several sources, including the scientific literature and international databases, along with climatic and hydrographic variables. Different phylogenetic analyses with either the COI or 16S-rRNA sequences did not conflict, but rather gave very similar topological organizations. Two major groups were identified, with sequences from the Pinturas River grouping together with haplotypes from subtropical and temperate regions. The model developed had a satisfactory performance for the study area. We observed that the areas

Changes in semi-arid plant species associations along a livestock grazing gradient.

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Hugo Saiz

Full Text Available In semi-arid ecosystems, vegetation is heterogeneously distributed, with plant species often associating in patches. These associations between species are not constant, but depend on the particular response of each species to environmental factors. Here, we investigated how plant species associations change in response to livestock grazing in a semi-arid ecosystem, Cabo de Gata-Níjar Natural Park in South East Spain. We established linear point-intercept transects at four sites with different grazing intensity, and recorded all species at each point. We investigated plant associations by comparing the number of times that each pair of species occurred at the same spatial point (co-occurrences, with the expected number of times based on species abundances. We also assessed associations for each shrub and grass species by considering all their pairs of associations and for the whole plant community by considering all pairs of associations on each site. At all sites, the plant community had a negative pattern of association, with fewer co-occurrences than expected. Negative association in the plant community increased at maximum grazing intensity. Most species associated as expected, particularly grass species, and positive associations were most important at intermediate grazing intensities. No species changed its type of association along the grazing gradient. We conclude that in the present plant community, grazing-resistant species compete among themselves and segregate in space. Some shrub species act as refuges for grazing-sensitive species that benefit from being spatially associated with shrub species, particularly at intermediate grazing intensities where positive associations were highest. At high grazing intensity, these shrubs can no longer persist and positive associations decrease due to the disappearance of refuges. Spatial associations between plant species and their response to grazing help identify the factors that organize

Mobile communication and intermediality

DEFF Research Database (Denmark)

Helles, Rasmus

2013-01-01

communicative affordances of mobile devices in order to understand how people choose between them for different purposes. It is argued that mobile communication makes intermediality especially central, as the choice of medium is detached from the location of stationary media and begins to follow the user across......The article argues the importance of intermediality as a concept for research in mobile communication and media. The constant availability of several, partially overlapping channels for communication (texting, calls, email, Facebook, etc.) requires that we adopt an integrated view of the various...

Stability of mutualisms in a lattice gas system of two species

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Yuanshi Wang

2015-01-01

Full Text Available This article considers mutualisms in a lattice gas system of two species. The species are mutualistic since each one can provide resources to the other. They are also competitive since they compete for empty sites on the same lattice. The mutualisms are assumed to have a saturated response, and the intraspecific competition is considered because of self-limitation. The mutualism system is characterized by differential equations, which are derived from reactions on lattice and are extension of a previous model. Global stability analysis demonstrates that (i When neither species can survive alone, they can coexist if mutualisms between them are strong and population densities are large, which exhibits the Allee effect in obligate mutualism; (ii When one species can survive alone but the other cannot, the latter one will survive if the mutualistic effect from the former is strong. Even if the effect is intermediate, the latter species can survive by strengthening its mutualistic effect on the former and enhancing its population density; (iii When either species can survive alone, a weak mutualism will lead to extinction of one species. When in coexistence, intermediate strength of mutualism is shown to be beneficial under certain parameter range, while over- or under- mutualism is not good. Furthermore, extremely strong/weak mutualism is exhibited to result in extinction of one/both species. While seven typical dynamics are displayed by numerical simulation in a previous work, they are proved in this work and the eighth one is exhibited. Numerical simul ations validate and extend our conclusions.

Classical model of intermediate statistics

International Nuclear Information System (INIS)

Kaniadakis, G.

1994-01-01

In this work we present a classical kinetic model of intermediate statistics. In the case of Brownian particles we show that the Fermi-Dirac (FD) and Bose-Einstein (BE) distributions can be obtained, just as the Maxwell-Boltzmann (MD) distribution, as steady states of a classical kinetic equation that intrinsically takes into account an exclusion-inclusion principle. In our model the intermediate statistics are obtained as steady states of a system of coupled nonlinear kinetic equations, where the coupling constants are the transmutational potentials η κκ' . We show that, besides the FD-BE intermediate statistics extensively studied from the quantum point of view, we can also study the MB-FD and MB-BE ones. Moreover, our model allows us to treat the three-state mixing FD-MB-BE intermediate statistics. For boson and fermion mixing in a D-dimensional space, we obtain a family of FD-BE intermediate statistics by varying the transmutational potential η BF . This family contains, as a particular case when η BF =0, the quantum statistics recently proposed by L. Wu, Z. Wu, and J. Sun [Phys. Lett. A 170, 280 (1992)]. When we consider the two-dimensional FD-BE statistics, we derive an analytic expression of the fraction of fermions. When the temperature T→∞, the system is composed by an equal number of bosons and fermions, regardless of the value of η BF . On the contrary, when T=0, η BF becomes important and, according to its value, the system can be completely bosonic or fermionic, or composed both by bosons and fermions

Comparative Analysis of End Point Enzymatic Digests of Arabino-Xylan Isolated from Switchgrass (Panicum virgatum L of Varying Maturities using LC-MSn

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Michael J. Bowman

2012-11-01

Full Text Available Switchgrass (Panicum virgatum L., SG is a perennial grass presently used for forage and being developed as a bioenergy crop for conversion of cell wall carbohydrates to biofuels. Up to 50% of the cell wall associated carbohydrates are xylan. SG was analyzed for xylan structural features at variable harvest maturities. Xylan from each of three maturities was isolated using classical alkaline extraction to yield fractions (Xyl A and B with varying compositional ratios. The Xyl B fraction was observed to decrease with plant age. Xylan samples were subsequently prepared for structure analysis by digesting with pure endo-xylanase, which preserved side-groups, or a commercial carbohydrase preparation favored for biomass conversion work. Enzymatic digestion products were successfully permethylated and analyzed by reverse-phase liquid chromatography with mass spectrometric detection (RP-HPLC-MSn. This method is advantageous compared to prior work on plant biomass because it avoids isolation of individual arabinoxylan oligomers. The use of RP-HPLC- MSn differentiated 14 structural oligosaccharides (d.p. 3–9 from the monocomponent enzyme digestion and nine oligosaccharide structures (d.p. 3–9 from hydrolysis with a cellulase enzyme cocktail. The distribution of arabinoxylan oligomers varied depending upon the enzyme(s applied but did not vary with harvest maturity.

Using Peephole Optimization on Intermediate Code

NARCIS (Netherlands)

Tanenbaum, A.S.; van Staveren, H.; Stevenson, J.W.

1982-01-01

Many portable compilers generate an intermediate code that is subsequently translated into the target machine's assembly language. In this paper a stack-machine-based intermediate code suitable for algebraic languages (e.g., PASCAL, C, FORTRAN) and most byte-addressed mini- and microcomputers is

Pair production of intermediate vector bosons

International Nuclear Information System (INIS)

Mikaelian, K.O.

1979-01-01

The production of intermediate vector boson pairs W + W - , Z 0 Z 0 , W +- Z 0 and W +- γ in pp and p anti p collisions is discussed. The motivation is to detect the self-interactions among the four intermediate vector bosons

Final Technical Report: Vibrational Spectroscopy of Transient Combustion Intermediates Trapped in Helium Nanodroplets

Energy Technology Data Exchange (ETDEWEB)

Douberly, Gary Elliott [Univ. of Georgia, Athens, GA (United States)

2017-11-16

The objective of our experimental research program is to isolate and stabilize transient intermediates and products of prototype combustion reactions. This will be accomplished by Helium Nanodroplet Isolation, a novel technique where liquid helium droplets freeze out high energy metastable configurations of a reacting system, permitting infrared spectroscopic characterizations of products and intermediates that result from hydrocarbon radical reactions with molecular oxygen and other small molecules relevant to combustion environments. The low temperature (0.4 K) and rapid cooling associated with He droplets provides a perfectly suited medium to isolate and probe a broad range of molecular radical and carbene systems important to combustion chemistry. The sequential addition of molecular species to He droplets often leads to the stabilization of high-energy, metastable cluster configurations that represent regions of the potential energy surface far from the global minimum. Single and double resonance IR laser spectroscopy techniques, along with Stark and Zeeman capabilities, are being used to probe the structural and dynamical properties of these systems.

A new species of Chasmodon Haliday (Hymenoptera, Braconidae, Alysiinae)

NARCIS (Netherlands)

Achterberg, van C.

1975-01-01

During an acarological study of brackish habitats in the Netherlands, a wingless species of Chasmodon was discovered. Because of the intermediate shape of the notauli it was not possible to identify it with the key of Hedqvist (1962), and therefore I propose another key for the wingless and

Language in use intermediate : classroom book

CERN Document Server

Doff, Adrian

1995-01-01

ach of the four levels comprises about 80 hours of class work, with additional time for the self-study work. The Teacher's Book contains all the pages from the Classroom Book, with interleaved teaching notes including optional activities to cater for different abilities. There is a video to accompany the Beginner, Pre-intermediate and Intermediate levels. Each video contains eight stimulating and entertaining short programmes, as well as a booklet of photocopiable activities. Free test material is available in booklet and web format for Beginner and Pre-intermediate levels. Visit www.cambridge.org/elt/liu or contact your local Cambridge University Press representative.

Language in use intermediate : teacher's book

CERN Document Server

Doff, Adrian

1998-01-01

Each of the four levels comprises about 80 hours of class work, with additional time for the self-study work. The Teacher's Book contains all the pages from the Classroom Book, with interleaved teaching notes including optional activities to cater for different abilities. There is a video to accompany the Beginner, Pre-intermediate and Intermediate levels. Each video contains eight stimulating and entertaining short programmes, as well as a booklet of photocopiable activities. Free test material is available in booklet and web format for Beginner and Pre-intermediate levels. Visit www.cambridge.org/elt/liu or contact your local Cambridge University Press representative.

Interpretation and code generation based on intermediate languages

DEFF Research Database (Denmark)

Kornerup, Peter; Kristensen, Bent Bruun; Madsen, Ole Lehrmann

1980-01-01

The possibility of supporting high level languages through intermediate languages to be used for direct interpretation and as intermediate forms in compilers is investigated. An accomplished project in the construction of an interpreter and a code generator using one common intermediate form...

Isolation and Spectroscopic Characterization of Reactive Species in Atmospheric and Interstellar Reactions

Science.gov (United States)

Relph, Rachael A.

2011-12-01

A critical element to the study of chemical reactions is the characterization of reaction intermediates. Methods have been developed to isolate these transient species in the gas phase and when combined with infrared spectroscopy have proven to be excellent tools for determining the structure and reactivity of key intermediates. The studies presented here exploit these technologies to better understand the chemistry of species involved in atmospheric and interstellar reactions. An excellent example of their utility is in the study of the formation of proton hydrates and HONO in the upper atmosphere by sequential addition of water molecules onto the nitrosonium ion. This reaction only proceeds to products after addition of the fourth water molecule, and isolation and characterization of the intermediate trihydrate, NO+(H 2O)3, shows that this species is formed in three isomeric forms, each with a different water network that controls the degree of bond formation between the nitrosonium ion and an activated water molecule. Many isomeric structures are also seen in the clustering reactions of acetylene which may be a mechanism for the formation of benzene cation in interstellar space. The spectroscopy of the trimer, (C2H2)3 + indicates that this species exists in two major isomer classes; covalent forms, one of which may be benzene, and an ion-molecule complex, comprised of a loosely bound acetylene on a dimer core. Interestingly, this dimer core is different from the cyclobutadiene-like structure observed in dimerized acetylene, and proves to be a robust species on the potential energy surface as it survives further clustering events. Two structural isomers of CO3 -and NO3 - are also investigated, and found to have drastically different infrared spectra which are analyzed in the context of their electronic structure. Isomers in these systems are prepared under different expansion conditions which accounts for their unique spectral signatures.

A non-flowering green panic grass (Panicum maximum var. trichoglume) obtained through gamma irradiation

International Nuclear Information System (INIS)

Shivashankar, G.; Mahishi, D.M.; Kulkarni, R.S.

1988-01-01

Full text: Suppression of flowering has many advantages in a forage crop. Such genotypes are not only expected to give more yield but also to be more nutritious. Non-flowering plants also remain fresh and green for a longer period in the field compared to the flowering types. Green panic (Panicum maximum var. trichoglume) is a high yielding, nutritious, fast growing and drought tolerant grass that has a potential to grow even under partial shade conditions. However, the major drawback of this grass is that it flowers early and profusely, with the result that most of the nutrients are diverted towards panicle formation. With an objective to suppress the panicle initiation a mutation breeding programme was taken up. Seeds of green panic grass were subjected to gamma ray treatment with doses of 40, 50 and 60 krad. From the large spectrum of variation observed for flowering habit quite a few non-flowering plants were isolated and of these the one from 40 krad treatment was prominent. This non-flowering plant yielded more green foliage than the flowering type and recorded an increase to the extend of 10.5% and 22.5% in monthly and bi-monthly harvests respectively. The increase in green foliage yield was directly attributable to an increase in the number of tillers and concomitant reduction in culm weight. Unlike in the flowering types the mutant had more accumulation of dry matter in the leaves rather than the stem. Further nutritional analysis of leaves showed that the non-flowering plant is superior with 6.04% crude protein which represents 100% increase over that of flowering type. The calcium content (0.5%) was also double and the moisture content (11.70%) was higher in the non-flowering plant. The crude fibre content was reduced by 2%. Inhibition of flowering is a common feature in mutagen treated material, but it is seldom inherited. In sugarcane non-arrowing mutants have been induced with advantage to increase the sugar content (Walker and Sisodia, 1969). The

Search for intermediate vector bosons

International Nuclear Information System (INIS)

Cline, D.B.; Rubbia, C.; van der Meer, S.

1982-01-01

Over the past 15 years a new class of unified theories has been developed to describe the forces acting between elementary particles. The most successful of the new theories establishes a link between electromagnetism and the weak force. A crucial prediction of this unified electroweak theory is the existence of three massive particles called intermediate vector bosons. If these intermediate vector bosons exist and if they have properties attributed to them by electroweak theory, they should soon be detected, as the world's first particle accelerator with enough energy to create such particles has recently been completed at the European Organization for Nuclear Research (CERN) in Geneva. The accelerator has been converted to a colliding beam machine in which protons and antiprotons collide head on. According to electroweak theory, intermediate vector bosons can be created in proton-antiproton collisions. (SC)

39 CFR 3001.39 - Intermediate decisions.

Science.gov (United States)

2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Intermediate decisions. 3001.39 Section 3001.39 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL RULES OF PRACTICE AND PROCEDURE Rules of General Applicability § 3001.39 Intermediate decisions. (a) Initial decision by presiding officer. In any proceedings in...

42 CFR 54.12 - Treatment of intermediate organizations.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Treatment of intermediate organizations. 54.12... intermediate organizations. If a nongovernmental organization (referred to here as an “intermediate organization”), acting under a contract or other agreement with the Federal Government or a State or local...

Formation, structure, and stability of MHD intermediate shocks

International Nuclear Information System (INIS)

Wu, C.C.

1990-01-01

Contrary to the usual belief that MHD intermediate shocks are extraneous, the author has recently shown by numerical solutions of dissipative MHD equations that intermediate shocks are admissible and can be formed through nonlinear wave steepening from continuous waves. In this paper, the formation, structure and stability of intermediate shocks in dissipative MHD are considered in detail. The differences between the conventional theory and his are pointed out and clarified. He shows that all four types of intermediate shocks can be formed from smooth waves. He also shows that there are free parameters in the structure of the intermediate shocks, and that these parameters are related to the shock stability. In addition, he shows that a rotational discontinuity can not exist with finite width, indicate how this is related to the existence of time-dependent intermediate shocks, and show why the conventional theory is not a good approximation to dissipative MHD solutions whenever there is rotation in magnetic field

Uptake and Effects of Six Rare Earth Elements (REEs on Selected Native and Crop Species Growing in Contaminated Soils.

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David Carpenter

Full Text Available Rare earth elements (REEs have become increasingly important metals used in modern technology. Processes including mining, oil refining, discarding of obsolete equipment containing REEs, and the use of REE-containing phosphate fertilizers may increase the likelihood of environmental contamination. However, there is a scarcity of information on the toxicity and accumulation of these metals to terrestrial primary producers in contaminated soils. The objective of this work was to assess the phytotoxicity and uptake from contaminated soil of six REEs (chloride forms of praseodymium, neodymium, samarium, terbium, dysprosium, and erbium on three native plants (Asclepias syriaca L., Desmodium canadense (L. DC., Panicum virgatum L. and two crop species (Raphanus sativus L., Solanum lycopersicum L. in separate dose-response experiments under growth chamber conditions. Limited effects of REEs were found on seed germination and speed of germination. Effects on aboveground and belowground biomass were more pronounced, especially for the three native species, which were always more sensitive than the crop species tested. Inhibition concentrations (IC25 and IC50 causing 25 or 50% reductions in plant biomass respectively, were measured. For the native species, the majority of aboveground biomass IC25s (11 out of 18 fell within 100 to 300 mg REE/kg dry soil. In comparison to the native species, IC25s for the crops were always greater than 400 mg REE/kg, with the majority of results (seven out of 12 falling above 700 mg REE/kg. IC50s were often not detected for the crops. Root biomass of native species was also affected at lower doses than in crops. REE uptake by plants was higher in the belowground parts than in the above-ground plant tissues. Results also revealed that chloride may have contributed to the sensitivity of the native species, Desmodium canadense, one of the most sensitive species studied. Nevertheless, these results demonstrated that

Corticotropin-releasing factor (CRF) receptors in intermediate lobe of the pituitary: Biochemical characterization and autoradiographic localization

International Nuclear Information System (INIS)

Grigoriadis, D.E.; De Souza, E.B.

1989-01-01

CRF receptors were characterized using radioligand binding and chemical affinity cross-linking techniques and localized using autoradiographic techniques in porcine, bovine and rat pituitaries. The binding of 125I-[Tyr0]-ovine CRF (125I-oCRF) to porcine anterior and neurointermediate lobe membranes was saturable and of high affinity with comparable KD values (200-600 pM) and receptor densities (100-200 fmoles/mg protein). The pharmacological rank order of potencies for various analogs and fragments of CRF in inhibiting 125I-oCRF binding in neurointermediate lobe was characteristic of the well-established CRF receptor in anterior pituitary. Furthermore, the binding of 125I-oCRF to both anterior and neurointermediate lobes of the pituitary was guanine nucleotide-sensitive. Affinity cross-linking studies revealed that the molecular weight of the CRF binding protein in rat intermediate lobe was identical to that in rat anterior lobe (Mr = 75,000). While the CRF binding protein in the anterior lobes of porcine and bovine pituitaries had identical molecular weights to CRF receptors in rat pituitary (Mr = 75,000), the molecular weight of the CRF binding protein in porcine and bovine intermediate lobe was slightly higher (Mr = 78,000). Pituitary autoradiograms from the three species showed specific binding sites for 125I-oCRF in anterior and intermediate lobes, with none being apparent in the posterior pituitary. The identification of CRF receptors in the intermediate lobe with comparable characteristics to those previously identified in the anterior pituitary substantiate further the physiological role of CRF in regulating intermediate lobe hormone secretion

Leptospira venezuelensis sp. nov., a new member of the intermediate group isolated from rodents, cattle and humans.

Science.gov (United States)

Puche, Rafael; Ferrés, Ignacio; Caraballo, Lizeth; Rangel, Yaritza; Picardeau, Mathieu; Takiff, Howard; Iraola, Gregorio

2018-02-01

Three strains, CLM-U50 T , CLM-R50 and IVIC-Bov1, belonging to the genus Leptospira, were isolated in Venezuela from a patient with leptospirosis, a domestic rat (Rattus norvegicus) and a cow (Bos taurus), respectively. The initial characterisation of these strains based on the rrs gene (16S rRNA) suggested their designation as a novel species within the 'intermediates' group of the genus Leptospira. Further phylogenomic characterisation based on single copy core genes was consistent with their separation into a novel species. The average nucleotide identity between these three strains was >99 %, but below 89 % with respect to any previously described leptospiral species, also supporting their designation as a novel species. Given this evidence, these three isolates were considered to represent a novel species, for which the name Leptospiravenezuelensis sp. nov. is proposed, with CLM-U50 T (=CIP 111407 T =DSM 105752 T ) as the type strain.

Pasture research in the wet and dry tropics of Nigeria with particular reference to isotope applications

International Nuclear Information System (INIS)

Adegbola, A.A.; Adepoju, A.

1983-01-01

Pasture research in western Nigeria, which typifies the wet and dry tropics of Nigeria, is discussed fully. Interest in pasture research in the area was kindled in 1930 with the introduction of Cynodon nlemfuensis var. robusta, but systematic work did not start until the 1950s. Early agronomic studies centred on easy means of establishing the adapted species from cuttings, sprigs or seeds. The most important species in the dry tropics is Andropogon gayanus, while in the wet tropics it is Panicum maximum. Later, investigations on yield of dry matter, intervals and height of cutting and response to fertilizer applications were carried out. Radioactive fertilizer 32 P- and 15 N-urea were also used to study the yield response of pasture to fertilizer application and to determine the percentage uptake of nutrients by plants. The results of such trials in different locations in the area are discussed extensively. Also, 32 P was used to determine the depth of active absorption of the root system of Andropogon gayanus and Panicum maximum, thus establishing their rooting pattern. (author)

Switchgrass (Panicum virgatum L. Genotypes Differ between Coastal Sites and Inland Road Corridors in the Northeastern US.

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Geoffrey Ecker

Full Text Available Switchgrass (Panicum virgatum L. is a North American grass that exhibits vast genetic diversity across its geographic range. In the Northeastern US, local switchgrass populations were restricted to a narrow coastal zone before European settlement, but current populations inhabit inland road verges raising questions about their origin and genetics. These questions are important because switchgrass lines with novel traits are being cultivated as a biofuel feedstock, and gene flow could impact the genetic integrity and distribution of local populations. This study was designed to determine if: 1 switchgrass plants collected in the Long Island Sound Coastal Lowland coastal Level IV ecoregion represented local populations, and 2 switchgrass plants collected from road verges in the adjacent inland regions were most closely related to local coastal populations or switchgrass from other geographic regions. The study used 18 microsatellite markers to infer the genetic relationships between 122 collected switchgrass plants and a reference dataset consisting of 28 cultivars representing ecotypes, ploidy levels, and lineages from North America. Results showed that 84% of 88 plants collected in the coastal plants were most closely aligned with the Lowland tetraploid genetic pool. Among this group, 61 coastal plants were similar to, but distinct from, all Lowland tetraploid cultivars in the reference dataset leading to the designation of a genetic sub-population called the Southern New England Lowland Tetraploids. In contrast, 67% of 34 plants collected in road verges in the inland ecoregions were most similar to two Upland octoploid cultivars; only 24% of roadside plants were Lowland tetraploid. These results suggest that cryptic, non-local genotypes exist in road verges and that gene flow from biofuels plantations could contribute to further changes in switchgrass population genetics in the Northeast.

Interactive effects of aluminum, phosphorus and mycorrhizae on growth and nutrient uptake of Panicum virgatum L. (Poaceae).

Science.gov (United States)

Koslowsky, S D; Boener, R E

1989-01-01

The effects of Al on Panicum virgatum (switchgrass), a widespread perennial grass, were determined in relation to factors which might interact with Al in the soil. Plants were grown for 8 weeks in sand culture and were treated with 3 Al levels (0.5, 2.0, 5.0 mM), 2 P levels (0.065, 0.161 mM), 2 inoculum types (vesicular-arbuscular mycorrhizal (VAM) inoculum or VAM-free soil inoculum) and 2 inoculum sources (a high Al forest in NY or a low Al forest in Ohio) in a factorial design. Plant growth decreased with increasing Al and increased with increasing P, but the Al effect was less at high P than low P. VAM-inoculated plants outgrew non-VAM plants, especially at low and medium Al levels. Total P and Ca uptake decreased with increasing Al concentration, especially at low P levels. VAM inoculation did not result in increased P uptake at any Al level though VAM plants took up significantly more Ca than non-VAM plants at any Al level. VAM plants had lower tissue Al concentrations and took up less Al than non-VAM plants; Al uptake increased with increasing soil Al in non-VAM plants but not in VAM plants. Plants given inoculum from the high Al site had significantly lower tissue Al than plants given the low Al site inoculum, regardless of VAM status. We conclude that the presence of a VAM infection, moderate levels of soil P, and the source of the inoculum can reduce the effects of soluble Al. We discuss potential physiological and edaphic mechanisms by which Al may be immobilized and Ca availability increased in the presence of VAM fungi and other soil microflora.

Partially folded intermediates during trypsinogen denaturation

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Martins N.F.

1999-01-01

Full Text Available The equilibrium unfolding of bovine trypsinogen was studied by circular dichroism, differential spectra and size exclusion HPLC. The change in free energy of denaturation was = 6.99 ± 1.40 kcal/mol for guanidine hydrochloride and = 6.37 ± 0.57 kcal/mol for urea. Satisfactory fits of equilibrium unfolding transitions required a three-state model involving an intermediate in addition to the native and unfolded forms. Size exclusion HPLC allowed the detection of an intermediate population of trypsinogen whose Stokes radii varied from 24.1 ± 0.4 Å to 26.0 ± 0.3 Å for 1.5 M and 2.5 M guanidine hydrochloride, respectively. During urea denaturation, the range of Stokes radii varied from 23.9 ± 0.3 Å to 25.7 ± 0.6 Å for 4.0 M and 6.0 M urea, respectively. Maximal intrinsic fluorescence was observed at about 3.8 M urea with 8-aniline-1-naphthalene sulfonate (ANS binding. These experimental data indicate that the unfolding of bovine trypsinogen is not a simple transition and suggest that the equilibrium intermediate population comprises one intermediate that may be characterized as a molten globule. To obtain further insight by studying intermediates representing different stages of unfolding, we hope to gain a better understanding of the complex interrelations between protein conformation and energetics.

Bacterial intermediate filaments

DEFF Research Database (Denmark)

Charbon, Godefroid; Cabeen, M.; Jacobs-Wagner, C.

2009-01-01

Crescentin, which is the founding member of a rapidly growing family of bacterial cytoskeletal proteins, was previously proposed to resemble eukaryotic intermediate filament (IF) proteins based on structural prediction and in vitro polymerization properties. Here, we demonstrate that crescentin...

Identification of Fasciola species based on mitochondrial and nuclear DNA reveals the co-existence of intermediate Fasciola and Fasciola gigantica in Thailand.

Science.gov (United States)

Wannasan, Anchalee; Khositharattanakool, Pathamet; Chaiwong, Prasong; Piangjai, Somsak; Uparanukraw, Pichart; Morakote, Nimit

2014-11-01

Molecular techniques were used to identify Fasciola species collected from Chiang Mai Thailand. Morphometrically, 65 stained and 45 fresh worms collected from cattle suggested the possible occurrence of both F. gigantica and F. hepatica. Twenty-two worms comprising 15 from cattle and 7 from human patients, were identified subsequently based on three genetic markers: mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunit 1 (nad1), mitochondrial cytochrome c oxidase subunit 1 (cox1) and nuclear ribosomal internal transcribed spacer 2 (ITS2). All of them presented the F. gigantica type in maternally inherited mitochondrial sequences (nad1 and cox1), with six types in each sequence (FgNDI-CM1 to FgNDI-CM6 and FgCOI-CM1 to FgCOI-CM6, respectively). Remarkably, the predominant nad1 type, FgNDI-CM6, was identical to that of aspermic Fasciola sp. formerly reported from Thailand, Japan, Korea, China, Vietnam, and Myanmar. ITS2 sequences were analyzed successfully in 20 worms. Fifteen worms showed the F. gigantica type and five (including one worm from a patient) had mixed ITS2 sequences of both F. gigantica and F. hepatica in the same worms, with additional heterogeneity within both ITS2 types. This study revealed the intermediate form of Fasciola coexisting with F. gigantica for the first time in Thailand.

NEW STRAIN PRODUCERS OF BIOBUTANOL. III. METHODS OF INCREASED BUTANOL ACCUMULATION FROM BIOMASS OF SWITCHGRASS Panicum virgatum L.

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Tigunova O. O.

2015-08-01

Full Text Available The aim of this work was to enlarge accumulation of butanol from switchgrass Panicum virgatum L. biomass using strains-producers obtained from grounds and silts of Kyiv lakes. The objects of the study were strains of C. acetobutylicum ІМВ B-7407 (IFBG C6H, Clostridium acetobutylicum IFBG C6H 5М and Clostridium tyrobutyricum IFBG C4B from the "Collections of microbial strains and lines of plants for food and agricultural biotechnology" of the Public Institution "Institute of Food Biotechnology and Genomics" of the National Academy of Sciences of Ukraine. Gas chromatography was used to determine the alcohol concentration at the stage of solvent synthesis. To determine the effect of butanol precursors during cultivation, butyric, lactic and acetic acids were used. Optimization of processing parameters, which was based on the needs of cultures, allowed us to increase the yield by 20 and 50% for the initial and mutant strain respectively. Using synthetic precursors (such as lactic, butyric and acetic acid during cultivation increased total concentration of butanol by 1.7 times. To optimize the process, a study was carried out using acetone- butyl grains. Using of acetone-butyl grains in concentrations up to 60% does not affect the synthesis of butanol by C. acetobutylicum IFBG C6H 5M. Increasing the concentration of grains led to decrease in accumulation of butanol. Almost double increase in accumulation of the target product (butanol was achieved using two-stage fermentation and/or precursors of synthesis. It was shown the possibility of using acetone-butyl grains in fermentation. As a result the mass fraction of the waste was reduced.

Detection and Identification of the Keto-Hydroperoxide (HOOCH 2 OCHO) and Other Intermediates during Low-Temperature Oxidation of Dimethyl Ether

KAUST Repository

Moshammer, Kai

2015-07-16

In this paper we report the detection and identification of the keto-hydroperoxide (hydroperoxymethyl formate, HPMF, HOOCH2OCHO) and other partially oxidized intermediate species arising from the low-temperature (540 K) oxidation of dimethyl ether (DME). These observations were made possible by coupling a jet-stirred reactor with molecular-beam sampling capabilities, operated near atmospheric pressure, to a reflectron time-of-flight mass spectrometer that employs single-photon ionization via tunable synchrotron-generated vacuum-ultraviolet radiation. On the basis of experimentally observed ionization thresholds and fragmentation appearance energies, interpreted with the aid of ab initio calculations, we have identified HPMF and its conceivable decomposition products HC(O)O(O)CH (formic acid anhydride), HC(O)OOH (performic acid), and HOC(O)OH (carbonic acid). Other intermediates that were detected and identified include HC(O)OCH3 (methyl formate), cycl-CH2-O-CH2-O- (1,3-dioxetane), CH3OOH (methyl hydroperoxide), HC(O)OH (formic acid), and H2O2 (hydrogen peroxide). We show that the theoretical characterization of multiple conformeric structures of some intermediates is required when interpreting the experimentally observed ionization thresholds, and a simple method is presented for estimating the importance of multiple conformers at the estimated temperature (∼100 K) of the present molecular beam. We also discuss possible formation pathways of the detected species: for example, supported by potential energy surface calculations, we show that performic acid may be a minor channel of the O2 + CH2OCH2OOH reaction, resulting from the decomposition of the HOOCH2OCHOOH intermediate, which predominantly leads to the HPMF. © 2015 American Chemical Society.

Present status of intermediate band solar cell research

International Nuclear Information System (INIS)

Cuadra, L.; Marti, A.; Luque, A.

2004-01-01

The intermediate band solar cell is a theoretical concept with the potential for exceeding the performance of conventional single-gap solar cells. This novel photovoltaic converter bases its superior theoretical efficiency over single-gap solar cells by enhancing its photogenerated current, via the two-step absorption of sub-band gap photons, without reducing its output voltage. This is achieved through a material with an electrically isolated and partially filled intermediate band located within a higher forbidden gap. This material is commonly named intermediate band material. This paper centres on summarising the present status of intermediate band solar cell research. A number of attempts, which aim to implement the intermediate band concept, are being followed: the direct engineering of the intermediate band material, its implementation by means of quantum dots and the highly porous material approach. Among other sub-band gap absorbing proposals, there is a renewed interest on the impurity photovoltaic effect, the quantum well solar cells and the particularly promising proposal for the use of up- and down-converters

Distribution and habitats of Lymnaea natalensis, snail intermediate host of the liver fluke Fasciola gigantica, in South Africa

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Editorial Office

2001-09-01

Full Text Available This paper focuses on the geographical distribution and the habitats of Lymnaea natalensis, the snail intermediate host of the liver fluke, Fasciola gigantica, as reflected by the collection sites of its 4 552 samples currently on record in the National Freshwater Snail Collection (NFSC of South Africa. Although this species was represented in a variety of waterbodies, the majority of samples(±70%came from rivers, brooks and dams and in 70.8% of the cases the water was described as permanent and in 71.8% as slow flowing or standing. The results of life-table studies conducted by various authors indicated that temperature should be a relatively unimportant factor in determining its geographical distribution, but that the availability of permanent water should be decisive for its presence in a given habitat. These results are in agreement with the finding that only 7.5% of the samples of this species in the NFSC were collected in habitats which were described as seasonal. Furthermore, it gives a logical explanation for the sporadic occurrence, or total absence of this species in the more arid regions of South Africa. Water impoundments and irrigation networks contribute to a large extent towards creating perennial habitats which would be suitable for L. natalensis. As intermediate host for one of the liver fluke species which already is an economic factor in South Africa, this certainly is an aspect which ought to be reckoned within the planning and construction of new irrigation schemes.

A New Species of Horseshoe Bat of the Genus Rhinolophus from China (Chiroptera: Rhinolophidae)

OpenAIRE

Wu, Yi; Motokawa, Masaharu; Harada, Masashi

2008-01-01

A new species of the Rhinolophus philippinensis group (Chiroptera: Rhinolophidae) is described from Guangdong, Guangxi, and Jiangxi Provinces in China. Rhinolophus huananus n. sp. is characterized by the horseshoe, as well as by external and cranial characteristics that separate it at the species level from the other members of the philippinensis group. One of the small species of the philippinensis group, R. huananus is intermediate in size between smaller R. siamensis and larger R. macrotis.

A new species of horseshoe bat of the genus Rhinolophus from China (Chiroptera: Rhinolophidae).

Science.gov (United States)

Wu, Yi; Motokawa, Masaharu; Harada, Masashi

2008-04-01

A new species of the Rhinolophus philippinensis group (Chiroptera: Rhinolophidae) is described from Guangdong, Guangxi, and Jiangxi Provinces in China. Rhinolophus huananus n. sp. is characterized by the horseshoe, as well as by external and cranial characteristics that separate it at the species level from the other members of the philippinensis group. One of the small species of the philippinensis group, R. huananus is intermediate in size between smaller R. siamensis and larger R. macrotis.

Estimates of hybridization between two species of catostomids in the Columbia River

Energy Technology Data Exchange (ETDEWEB)

Dauble, D.D.; Buschbom, R.L.

1981-01-01

Extent of hybridization is described between two sympatric catostomids, Catostomus macrocheilus and C. columbianus, from the Hanford Reach of the Columbia River, southeastern Washington state. Estimated percentage of hybrids based on presence of intermediate meristic characters ranged from 12.4 to 14.6% of the total sucker population. Discriminant function analysis reduced subjective variability and lowered estimates of hybridization to 3.0 to 7.1%. Principal component analysis also provided evidence that the suspected hybrids were intermediate between populations of C. macrocheilus and C. columbianus. Meristic characters contributed most to all methods of treatment, with number of lateral line scales the best single criterion for species separation. Any analysis of closely related species would benefit from examination of offspring from artificial crosses and from knowledge of allopatric population characteristics. Breakdown of isolating mechanisms leading to C. macrocheilus X C. columbianus crosses may result from overlap in spawning time and incomplete habitat segregation. Morphological and coloration differences at spawning may provide a basis for species recognition, thus providing some degree of ethological isolation.

Sarcocystis pantherophis, n. sp. from eastern rat snakes (Pantherophis alleghaniensis) definitive hosts and interferongamma gene knockout mice as experimental intermediate hosts

Science.gov (United States)

Here we report a new species, Sarcocystis pantherophisi with the Eastern rat snake (Pantherophis alleghaniensis) as natural definitive host and the interferon gamma gene knockout (KO) mouse as the experimental intermediate host. Sporocysts (n=15) from intestinal contents of the snake were 17.3 x 10....

Gas exchange and stand-level estimates of water use and gross primary productivity in an experimental pine and switchgrass intercrop forestry system on the Lower Coastal Plain of North Carolina, U.S.A

Science.gov (United States)

Janine M. Albaugha; Jean-Christophe Domeca; Chris A. Maier; Eric B. Sucre; Zakiya H. Leggett; John S. King

2014-01-01

Despite growing interest in using switchgrass (Panicum virgatum L.) as a biofuel, there are limiteddata on the physiology of this species and its effect on stand water use and carbon (C) assimilationwhen grown as a forest intercrop for bioenergy. Therefore, we quantified gas exchange rates of switch-grass within intercropped plots and in pure switchgrass plots during...

Atividade relativa da catalase de losna-branca (Parthenium hysterophorus comparada à de outras espécies daninhas Catalase relative activity of ragweed (Parthenium hysterophorus compared to that of other weed species

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S.J.P. Carvalho

2012-06-01

Full Text Available Este trabalho foi desenvolvido com o objetivo de avaliar a atividade relativa da catalase em extrato aquoso de losna-branca (Parthenium hysterophorus, bem como comparála à atividade da catalase de outras espécies daninhas. O trabalho constou de três fases, que envolveram a padronização do método, comparação da atividade relativa da catalase de plantas da família Asteraceae e comparação com outras 11 espécies daninhas, sendo estas: Euphorbia heterophylla, Alternanthera tenella, Cenchrus echinatus, Panicum maximum, Amaranthus viridis, Ipomoea hederifolia, Galinsoga parviflora, Bidens pilosa, Sonchus oleraceus, Cyperus rotundus e Commelina benghalensis. Observou-se resposta linear crescente da reação entre extrato aquoso de losna-branca e peróxido de hidrogênio, em razão da concentração do extrato vegetal. Em todas as fases, a atividade relativa da catalase de extrato de losna-branca foi superior à atividade da catalase das demais espécies daninhas. Com os dados obtidos nas três fases, conclui-se que a maior atividade relativa observada para a catalase da losnabranca contribui significativamente para a tolerância dessa espécie ao herbicida paraquat. Essa maior atividade pode ser consequência da maior concentração enzimática nas células ou devido à maior atividade intrínseca da enzima (afinidade enzima-substrato, havendo necessidade de estudos mais precisos para essa conclusão.This work was carried out to evaluate catalase relative activity of ragweed (Parthenium hysterophorus aqueous extract, as well as to compare it with catalase activity of other weed species. It consisted of three phases, involving method standardization, comparison of the catalase relative activity in Asteraceae family plants and that of ragweed catalase activity with the following 11 weed species: Euphorbia heterophylla, Alternanthera tenella, Cenchrus echinatus, Panicum maximum, Amaranthus viridis, Ipomoea hederifolia, Galinsoga parviflora

Nucleic acid binding properties and intermediates of HCV core protein multimerization in Pichia pastoris

International Nuclear Information System (INIS)

Acosta-Rivero, Nelson; Rodriguez, Armando; Musacchio, Alexis; Falcon, Viviana; Suarez, Viana M.; Chavez, Liudmila; Morales-Grillo, Juan; Duenas-Carrera, Santiago

2004-01-01

Little is known about the in vivo assembly pathway or structure of the hepatitis C virus nucleocapsid. In this work the intermediates of HCcAg multimerization in Pichia pastoris cells and the nucleic acid binding properties of structured nucleocapsid-like particles (NLPs) were studied. Extensive cross-linking was observed for HCcAg after glutaraldehyde treatment. Data suggest that HCcAg exists in dimeric forms probably representing P21-P21, P21-P23, and P23-P23 dimers. In addition, the presence of HCcAg species that might represent trimers and multimers was observed. After sucrose equilibrium density gradient purification and nuclease digestion, NLPs were shown to contain both RNA and DNA molecules. Finally, the analysis by electron microscopy indicated that native NLPs were resistant to nuclease treatment. These results indicated that HCcAg assembles through dimers, trimers, and multimers' intermediates into capsids in P. pastoris cells. Assembly of NLPs in its natural environment might confer stability to these particles by adopting a compact structure

Screening of plant species as ground cover on uranium mill tailings

International Nuclear Information System (INIS)

Venu Babu, P.; Eapen, S.

2012-01-01

residual mill tailings apart from containing residual radionuclides do have the capacity to support good plant growth. Several species like Rhynchosia minima, Rhynchosia, Thysanolaena maxima, Mucuna pruriens, Desmanthus virgatus, Desmodium gangeticum, Clitoria tematea, Chrysopogon fulvus and Indigofera trita were found to be quite suitable for planting on mill tailings as ground cover while a few others that registered poor growth and/or biomass perhaps can be grown in combination with other species. On the contrary a few species viz., Bothriochloa pertusa, Cenchrus ciliaris, Panicum antidotale and Pennisetum caudatum were found to be unsuitable as they could not survive in mill tailings. A combination of several plant species tested in this study coupled with a few agronomic practices can be tried on mill tailings in Jaduguda as an appropriate vegetative cover. (author)

Effects of low atmospheric CO2 and elevated temperature during growth on the gas exchange responses of C3, C3-C4 intermediate, and C4 species from three evolutionary lineages of C4 photosynthesis.

Science.gov (United States)

Vogan, Patrick J; Sage, Rowan F

2012-06-01

This study evaluates acclimation of photosynthesis and stomatal conductance in three evolutionary lineages of C(3), C(3)-C(4) intermediate, and C(4) species grown in the low CO(2) and hot conditions proposed to favo r the evolution of C(4) photosynthesis. Closely related C(3), C(3)-C(4), and C(4) species in the genera Flaveria, Heliotropium, and Alternanthera were grown near 380 and 180 μmol CO(2) mol(-1) air and day/night temperatures of 37/29°C. Growth CO(2) had no effect on photosynthetic capacity or nitrogen allocation to Rubisco and electron transport in any of the species. There was also no effect of growth CO(2) on photosynthetic and stomatal responses to intercellular CO(2) concentration. These results demonstrate little ability to acclimate to low CO(2) growth conditions in closely related C(3) and C(3)-C(4) species, indicating that, during past episodes of low CO(2), individual C(3) plants had little ability to adjust their photosynthetic physiology to compensate for carbon starvation. This deficiency could have favored selection for more efficient modes of carbon assimilation, such as C(3)-C(4) intermediacy. The C(3)-C(4) species had approximately 50% greater rates of net CO(2) assimilation than the C(3) species when measured at the growth conditions of 180 μmol mol(-1) and 37°C, demonstrating the superiority of the C(3)-C(4) pathway in low atmospheric CO(2) and hot climates of recent geological time.

Associations of Systemic Diseases with Intermediate Uveitis.

Science.gov (United States)

Shoughy, Samir S; Kozak, Igor; Tabbara, Khalid F

2016-01-01

To determine the associations of systemic diseases with intermediate uveitis. The medical records of 50 consecutive cases with intermediate uveitis referred to The Eye Center in Riyadh, Saudi Arabia, were reviewed. Age- and sex-matched patients without uveitis served as controls. Patients had complete ophthalmic and medical examinations. There were 27 male and 23 female patients. Mean age was 29 years with a range of 5-62 years. Overall, 21 cases (42%) had systemic disorders associated with intermediate uveitis and 29 cases (58%) had no associated systemic disease. A total of 11 patients (22%) had asthma, 4 (8%) had multiple sclerosis, 3 (6%) had presumed ocular tuberculosis, 1 (2%) had inflammatory bowel disease, 1 (2%) had non-Hodgkin lymphoma and 1 (2%) had sarcoidosis. Evidence of systemic disease was found in 50 (5%) of the 1,000 control subjects. Bronchial asthma was found in 37 patients (3.7 %), multiple sclerosis in 9 patients (0.9%), inflammatory bowel disease in 3 patients (0.3%), and tuberculosis in 1 patient (0.1%). None of the control patients had sarcoidosis or lymphoma. There were statistically significant associations between intermediate uveitis and bronchial asthma (p = 0.0001), multiple sclerosis (p = 0.003) and tuberculosis (p = 0.0005). Bronchial asthma and multiple sclerosis were the most frequently encountered systemic diseases associated with intermediate uveitis in our patient population. Patients with intermediate uveitis should undergo careful history-taking and investigations to rule out associated systemic illness.

Comparative sensitivity of five species of macrophytes and six species of algae to atrazine, metribuzin, alachlor, and metolachlor

Science.gov (United States)

Fairchild, James F.; Ruessler, Shane; Carlson, A. Ron

1998-01-01

This study determined the relative sensitivity of five species of aquatic macrophytes and six species of algae to four commonly used herbicides (atrazine, metribuzin, alachlor, and metolachlor). Toxicity tests consisted of 96-h (duckweed and algae) or 14-d (submerged macrophytes) static exposures. The triazine herbicides (atrazine and metribuzin) were significantly more toxic to aquatic plants than were the acetanilide herbicides (alachlor and metolachlor). Toxicity studies ranked metribuzin > atrazine > alachlor > metolachlor in decreasing order of overall toxicity to aquatic plants. Relative sensitivities of macrophytes to these herbicides decreased in the order of Ceratophyllum > Najas > Elodea > Lemna > Myriophyllum. Relative sensitivities of algae to herbicides decreased in the order of Selenastrum > Chlorella > Chlamydomonas > Microcystis > Scenedesmus > Anabaena. Algae and macrophytes were of similar overall sensitivities to herbicides. Data indicated that Selenastrum, a commonly tested green alga, was generally more sensitive compared to other plant species. Lemna minor, a commonly tested floating vascular plant, was of intermediate sensitivity, and was fivefold less sensitive than Ceratophyllum, which was the most sensitive species tested. The results indicated that no species was consistently most sensitive, and that a suite of aquatic plant test species may be needed to perform accurate risk assessments of herbicides.

Nitrogen atom transfer mediated by a new PN3P-pincer nickel core via a putative nitrido nickel intermediate

KAUST Repository

Yao, Changguang

2018-02-13

A 2nd generation PN3P-pincer azido nickel complex (PN3P)Ni(N3) reacts with isocyanides to afford monosubstituted carbodiimides under irradiation, presumably via a transient nitrido intermediate. The resulting species can further generate unsymmetrical carboddimides and the PN3P nickel halide complex, accomplishing a synthetic cycle for a complete nitrogen atom transfer reaction.

Nitrogen atom transfer mediated by a new PN3P-pincer nickel core via a putative nitrido nickel intermediate

KAUST Repository

Yao, Changguang; Wang, Xiufang; Huang, Kuo-Wei

2018-01-01

A 2nd generation PN3P-pincer azido nickel complex (PN3P)Ni(N3) reacts with isocyanides to afford monosubstituted carbodiimides under irradiation, presumably via a transient nitrido intermediate. The resulting species can further generate unsymmetrical carboddimides and the PN3P nickel halide complex, accomplishing a synthetic cycle for a complete nitrogen atom transfer reaction.

Differential cross sections for electron-impact vibrational-excitation of tetrahydrofuran at intermediate impact energies

Energy Technology Data Exchange (ETDEWEB)

Do, T. P. T. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); School of Education, Can Tho University, Campus II, 3/2 Street, Xuan Khanh, Ninh Kieu, Can Tho City (Viet Nam); Duque, H. V. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Departamento de Física, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora, Minas Gerais (Brazil); Lopes, M. C. A. [Departamento de Física, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora, Minas Gerais (Brazil); Konovalov, D. A.; White, R. D. [College of Science, Technology and Engineering, James Cook University, Townsville (Australia); Brunger, M. J., E-mail: michael.brunger@flinders.edu.au, E-mail: darryl.jones@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Jones, D. B., E-mail: michael.brunger@flinders.edu.au, E-mail: darryl.jones@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia)

2015-03-28

We report differential cross sections (DCSs) for electron-impact vibrational-excitation of tetrahydrofuran, at intermediate incident electron energies (15-50 eV) and over the 10°-90° scattered electron angular range. These measurements extend the available DCS data for vibrational excitation for this species, which have previously been obtained at lower incident electron energies (≤20 eV). Where possible, our data are compared to the earlier measurements in the overlapping energy ranges. Here, quite good agreement was generally observed where the measurements overlapped.

Role of the metal oxidation state in the SNS-Cr catalyst for ethylene trimerization: Isolation of Di- and trivalent cationic intermediates

NARCIS (Netherlands)

Jabri, A.; Temple, C.N.; Crewdson, P.; Gambarotta, S.; Korobkov, I.V.; Duchateau, R.

2006-01-01

The reaction of the highly selective [CySCH2CH2N(H)CH2CH2SCy]CrCl3 catalyst precursor with alkyl aluminum activators was examined with the aim of isolating reactive intermediates. Reaction with Me3Al afforded a cationic trivalent chromium alkyl species

Natural hybridization in the sea urchin genus Pseudoboletia between species without apparent barriers to gamete recognition.

Science.gov (United States)

Zigler, Kirk S; Byrne, Maria; Raff, Elizabeth C; Lessios, H A; Raff, Rudolf A

2012-06-01

Marine species with high dispersal potential often have huge ranges and minimal population structure. Combined with the paucity of geographic barriers in the oceans, this pattern raises the question as to how speciation occurs in the sea. Over the past 20 years, evidence has accumulated that marine speciation is often linked to the evolution of gamete recognition proteins. Rapid evolution of gamete recognition proteins in gastropods, bivalves, and sea urchins is correlated with gamete incompatibility and contributes to the maintenance of species boundaries between sympatric congeners. Here, we present a counterexample to this general pattern. The sea urchins Pseudoboletia indiana and P. maculata have broad ranges that overlap in the Indian and Pacific oceans. Cytochrome oxidase I sequences indicated that these species are distinct, and their 7.3% divergence suggests that they diverged at least 2 mya. Despite this, we suspected hybridization between them based on the presence of morphologically intermediate individuals in sympatric populations at Sydney, Australia. We assessed the opportunity for hybridization between the two species and found that (1) individuals of the two species occur within a meter of each other in nature, (2) they have overlapping annual reproductive cycles, and (3) their gametes cross-fertilize readily in the laboratory and in the field. We genotyped individuals with intermediate morphology and confirmed that many were hybrids. Hybrids were fertile, and some female hybrids had egg sizes intermediate between the two parental species. Consistent with their high level of gamete compatibility, there is minimal divergence between P. indiana and P. maculata in the gamete recognition protein bindin, with a single fixed amino acid difference between the two species. Pseudoboletia thus provides a well-characterized exception to the idea that broadcast spawning marine species living in sympatry develop and maintain species boundaries through the

screening of twenty-four south african combretum species and six ...

African Journals Online (AJOL)

Prof. Clement Adewunmi

of finely ground plant material and extracting with 10 ml of acetone, hexane, ... chloroform/ethyl acetate/formic acid (5:4:1): [CEF] (intermediate polarity/acidic); benzene/- ... This figure was used as the representative of all Combretum species and ... (bottom) solvent systems and sprayed with 0.2% DPPH in methanol. Yellow ...

Etude comparative de la digestibilité in vivo de l'herbe de guinée (Panicum maximum Jacq. associée aux feuilles et tiges de patate douce (Ipomoea batatas (L. Lam (régime Panipo ou à l'herbe de lait (Euphorbia heterophylla L. (régime Paneuph chez le lapin (Oryctolagus cuniculus L. et le cobaye (Cavia porcellus L.

Directory of Open Access Journals (Sweden)

Kouakou, NGDV.

2016-01-01

Full Text Available Digestibility of Guinea grass (Panicum maximum Jacq. associated with sweet potato leaves and stems (Ipomoea batatas (L. Lam (Panipo diet or poison milk (Euphorbia heterophylla L. (Paneuph diet in Rabbits (Oryctolagus cuniculus L. and in Guinea Pigs (Cavia porcellus L.. A comparative study of in vivo digestibility of Guinea grass (Panicum maximum Jacq. associated with sweet potato leaves and stems (Ipomoea batatas (L. Lam (Panipo diet or with poison milk (Euphorbia heterophylla L. (Paneuph diet was conducted involving 16 rabbits and 16 weaned guinea pigs fed ad libitum. Paneuph was significantly better ingested (P0.05 for guinea pigs. Poison milk was better ingested than the leaves and stems of sweet potato (P0.05. The ADC of DM, OM and MAT of Paneuph exceeded 80% and were higher than those of Panipo in rabbits and guinea pigs (P<0.05. Based on the results obtained, the effects of the distribution of the Guinea grass associated with the poison milk during rabbits growing have to be further studied before recommending this new diet to farmers in areas where poison milk and Guinea grass are present and rabbit breeding enough developed.

Perfil de n-alcanos em cinco espécies de plantas forrageiras tropicais - DOI: 10.4025/actascianimsci.v27i3.1207 Profile of n-alkanes in five species of plants tropical forages - DOI: 10.4025/actascianimsci.v27i3.1207

Directory of Open Access Journals (Sweden)

Antônio Ferriani Branco

2005-03-01

Full Text Available O objetivo do experimento foi estudar o perfil de n-alcanos em espécies de gramíneas (Brachiaria brizantha, Cynodon dactylon e Panicum maximum e leguminosas (Arachis pintoi e Glycine wightii. Foram identificados e quantificados por meio de cromatografia gasosa, os n-alcanos C24 a C35, sendo C32 e C34 padrões internos. As concentrações dos n-alcanos nas diferentes espécies e respectivas frações (lâminas foliares, colmos porções superior e inferior e matéria morta para gramíneas; folhas, caule porção superior e inferior e matéria morta para leguminosas foram submetidas à análise de variância e teste de média (Tukey. Nos períodos de primavera e inverno, para a maioria das espécies e frações, há predomínio dos n-alcanos de cadeia ímpar. Houve maior concentração de C29, C31 e C33 na primavera, C27, C28, C29, C30 e C31, no verão e C27, C29, C31 e C33 no invernoThis experiment aimed to study the profile of n-alkanes in tropical grasses species (Brachiaria brizantha, Cynodon dactylon and Panicum maximum and legumes (Arachis pintoi and Glycine wightii. They were identified and quantified, through gas cromatography, the n-alkanes C24 to C35, being the alkanes C32 and C34 internal indices. The n-alkanes concentrations in the different species and respective fractions (leaf blade, stem higher and lower portion and dead matter for grasses; leaves, stem higher portion, stem lower portion and dead matter for legumes were submitted to variance analysis and mean test (Tukey. For most of the species and fractions, there is prevalence of odd chain n-alkanes during springtime and winter. There was larger concentration of the alkanes C29, C31 and C33 in springtime, C27, C28, C29, C30 and C31 in summer and C27, C29, C31 and C33 in winter

Exploring the negative temperature coefficient behavior of acetaldehyde based on detailed intermediate measurements in a jet-stirred reactor

KAUST Repository

Tao, Tao; Sun, Wenyu; Hansen, Nils; Jasper, Ahren W.; Moshammer, Kai; Chen, Bingjie; Wang, Zhandong; Huang, Can; Dagaut, Philippe; Yang, Bin

2018-01-01

Acetaldehyde is an observed emission species and a key intermediate produced during the combustion and low-temperature oxidation of fossil and bio-derived fuels. Investigations into the low-temperature oxidation chemistry of acetaldehyde are essential to develop a better core mechanism and to better understand auto-ignition and cool flame phenomena. Here, the oxidation of acetaldehyde was studied at low-temperatures (528–946 K) in a jet-stirred reactor (JSR) with the corrected residence time of 2.7 s at 700 Torr. This work describes a detailed set of experimental results that capture the negative temperature coefficient (NTC) behavior in the low-temperature oxidation of acetaldehyde. The mole fractions of 28 species were measured as functions of the temperature by employing a vacuum ultra-violet photoionization molecular-beam mass spectrometer. To explain the observed NTC behavior, an updated mechanism was proposed, which well reproduces the concentration profiles of many observed peroxide intermediates. The kinetic analysis based on the updated mechanism reveals that the NTC behavior of acetaldehyde oxidation is caused by the competition between the O-addition to and the decomposition of the CHCO radical.

Exploring the negative temperature coefficient behavior of acetaldehyde based on detailed intermediate measurements in a jet-stirred reactor

KAUST Repository

Tao, Tao

2018-03-20

Acetaldehyde is an observed emission species and a key intermediate produced during the combustion and low-temperature oxidation of fossil and bio-derived fuels. Investigations into the low-temperature oxidation chemistry of acetaldehyde are essential to develop a better core mechanism and to better understand auto-ignition and cool flame phenomena. Here, the oxidation of acetaldehyde was studied at low-temperatures (528–946 K) in a jet-stirred reactor (JSR) with the corrected residence time of 2.7 s at 700 Torr. This work describes a detailed set of experimental results that capture the negative temperature coefficient (NTC) behavior in the low-temperature oxidation of acetaldehyde. The mole fractions of 28 species were measured as functions of the temperature by employing a vacuum ultra-violet photoionization molecular-beam mass spectrometer. To explain the observed NTC behavior, an updated mechanism was proposed, which well reproduces the concentration profiles of many observed peroxide intermediates. The kinetic analysis based on the updated mechanism reveals that the NTC behavior of acetaldehyde oxidation is caused by the competition between the O-addition to and the decomposition of the CHCO radical.

An analysis of species boundaries and biogeographic patterns in a cryptic species complex: the rotifer--Brachionus plicatilis.

Science.gov (United States)

Suatoni, Elizabeth; Vicario, Saverio; Rice, Sean; Snell, Terry; Caccone, Adalgisa

2006-10-01

Since the advent of molecular phylogenetics, there is increasing evidence that many small aquatic and marine invertebrates--once believed to be single, cosmopolitan species--are in fact cryptic species complexes. Although the application of the biological species concept is central to the identification of species boundaries in these cryptic complexes, tests of reproductive isolation do not frequently accompany phylogenetic studies. Because different species concepts generally identify different boundaries in cryptic complexes, studies that apply multiple species concepts are needed to gain a more detailed understanding of patterns of diversification in these taxa. Here we explore different methods of empirically delimiting species boundaries in the salt water rotifer Brachionus plicatilis by comparing reproductive data (i.e., the traditional biological species concept) to phylogenetic data (the genealogical species concept). Based on a high degree of molecular sequence divergence and largely concordant genetic patterns in COI and ITS1, the genealogical species hypothesis indicates the existence of at least 14 species--the highest estimate for the group thus far. A test of the genealogical species concept with biological crosses shows a fairly high level of concordance, depending on the degree of reproductive success used to draw boundaries. The convergence of species concepts in this group suggests that many of the species within the group may be old. Although the diversity of the group is higher than previously understood, geographic distributions remain broad. Efficient passive dispersal has resulted in global distributions for many species with some evidence of isolation by distance over large geographic scales. These patterns concur with expectations that micro-meiofauna (0.1-1mm) have biogeographies intermediate to microbial organisms and large vertebrates. Sympatry of genetically distant strains is common.

Isoporphyrin Intermediate in Heme Oxygenase Catalysis

Science.gov (United States)

Evans, John P.; Niemevz, Fernando; Buldain, Graciela; de Montellano, Paul Ortiz

2008-01-01

Human heme oxygenase-1 (hHO-1) catalyzes the O2- and NADPH-dependent oxidation of heme to biliverdin, CO, and free iron. The first step involves regiospecific insertion of an oxygen atom at the α-meso carbon by a ferric hydroperoxide and is predicted to proceed via an isoporphyrin π-cation intermediate. Here we report spectroscopic detection of a transient intermediate during oxidation by hHO-1 of α-meso-phenylheme-IX, α-meso-(p-methylphenyl)-mesoheme-III, and α-meso-(p-trifluoromethylphenyl)-mesoheme-III. In agreement with previous experiments (Wang, J., Niemevz, F., Lad, L., Huang, L., Alvarez, D. E., Buldain, G., Poulos, T. L., and Ortiz de Montellano, P. R. (2004) J. Biol. Chem. 279, 42593–42604), only the α-biliverdin isomer is produced with concomitant formation of the corresponding benzoic acid. The transient intermediate observed in the NADPH-P450 reductase-catalyzed reaction accumulated when the reaction was supported by H2O2 and exhibited the absorption maxima at 435 and 930 nm characteristic of an isoporphyrin. Product analysis by reversed phase high performance liquid chromatography and liquid chromatography electrospray ionization mass spectrometry of the product generated with H2O2 identified it as an isoporphyrin that, on quenching, decayed to benzoylbiliverdin. In the presence of H218O2, one labeled oxygen atom was incorporated into these products. The hHO-1-isoporphyrin complexes were found to have half-lives of 1.7 and 2.4 h for the p-trifluoromethyl- and p-methyl-substituted phenylhemes, respectively. The addition of NADPH-P450 reductase to the H2O2-generated hHO-1-isoporphyrin complex produced α-biliverdin, confirming its role as a reaction intermediate. Identification of an isoporphyrin intermediate in the catalytic sequence of hHO-1, the first such intermediate observed in hemoprotein catalysis, completes our understanding of the critical first step of heme oxidation. PMID:18487208

On the characterization of intermediates in the isodesmic aggregation pathway of hen lysozyme at alkaline pH.

Directory of Open Access Journals (Sweden)

Vijay Kumar Ravi

Full Text Available Protein aggregation leading to formation of amyloid fibrils is a symptom of several diseases like Alzheimer's, type 2 diabetes and so on. Elucidating the poorly understood mechanism of such phenomena entails the difficult task of characterizing the species involved at each of the multiple steps in the aggregation pathway. It was previously shown by us that spontaneous aggregation of hen-eggwhite lysozyme (HEWL at room temperature in pH 12.2 is a good model to study aggregation. Here in this paper we investigate the growth kinetics, structure, function and dynamics of multiple intermediate species populating the aggregation pathway of HEWL at pH 12.2. The different intermediates were isolated by varying the HEWL monomer concentration in the 300 nM-0.12 mM range. The intermediates were characterized using techniques like steady-state and nanosecond time-resolved fluorescence, atomic force microscopy and dynamic light scattering. Growth kinetics of non-fibrillar HEWL aggregates were fitted to the von Bertalanffy equation to yield a HEWL concentration independent rate constant (k = (6.6 ± 0.6 × 10(-5 s(-1. Our results reveal stepwise changes in size, molecular packing and enzymatic activity among growing HEWL aggregates consistent with an isodesmic aggregation model. Formation of disulphide bonds that crosslink the monomers in the aggregate appear as a unique feature of this aggregation. AFM images of multiple amyloid fibrils emanating radially from amorphous aggregates directly confirmed that on-pathway fibril formation was feasible under isodesmic polymerization. The isolated HEWL aggregates are revealed as polycationic protein nanoparticles that are robust at neutral pH with ability to take up non-polar molecules like ANS.

Intermediates detected by visible spectroscopy during the reaction of nitrite with deoxyhemoglobin: the effect of nitrite concentration and diphosphoglycerate.

Science.gov (United States)

Nagababu, Enika; Ramasamy, Somasundaram; Rifkind, Joseph M

2007-10-16

The reaction of nitrite with deoxyhemoglobin (deoxyHb) results in the reduction of nitrite to NO, which binds unreacted deoxyHb forming Fe(II)-nitrosylhemoglobin (Hb(II)NO). The tight binding of NO to deoxyHb is, however, inconsistent with reports implicating this reaction with hypoxic vasodilation. This dilemma is resolved by the demonstration that metastable intermediates are formed in the course of the reaction of nitrite with deoxyHb. The level of intermediates is quantitated by the excess deoxyHb consumed over the concentrations of the final products formed. The dominant intermediate has a spectrum that does not correspond to that of Hb(III)NO formed when NO reacts with methemoglobin (MetHb), but is similar to metHb resulting in the spectroscopic determinations of elevated levels of metHb. It is a delocalized species involving the heme iron, the NO, and perhaps the beta-93 thiol. The putative role for red cell reacted nitrite on vasodilation is associated with reactions involving the intermediate. (1) The intermediate is less stable with a 10-fold excess of nitrite and is not detected with a 100-fold excess of nitrite. This observation is attributed to the reaction of nitrite with the intermediate producing N2O3. (2) The release of NO quantitated by the formation of Hb(II)NO is regulated by changes in the distal heme pocket as shown by the 4.5-fold decrease in the rate constant in the presence of 2,3-diphosphoglycerate. The regulated release of NO or N2O3 as well as the formation of the S-nitroso derivative of hemoglobin, which has also been reported to be formed from the intermediates generated during nitrite reduction, should be associated with any hypoxic vasodilation attributed to the RBC.

Language in use intermediate : self-study workbook

CERN Document Server

Doff, Adrian

1994-01-01

Each of the four levels comprises about 80 hours of class work, with additional time for the self-study work. The Teacher's Book contains all the pages from the Classroom Book, with interleaved teaching notes including optional activities to cater for different abilities. There is a video to accompany the Beginner, Pre-intermediate and Intermediate levels. Each video contains eight stimulating and entertaining short programmes, as well as a booklet of photocopiable activities. Free test material is available in booklet and web format for Beginner and Pre-intermediate levels. Visit www.cambridge.org/elt/liu or contact your local Cambridge University Press representative.

an intermediate moisture meat

African Journals Online (AJOL)

STORAGESEVER

2008-07-04

Jul 4, 2008 ... traditional SM muscle without compromising quality. ... technique is intermediate moisture food processing. ... Traditionally, most tsire suya producers use ..... quality of Chinese purebred and European X Chinese crossbred ...

Comportamiento de 19 accesiones de Panicum maximum Jacq. bajo condiciones de pastoreo en un suelo de mediana fertilidad

Directory of Open Access Journals (Sweden)

R Machado

Full Text Available El objetivo de este trabajo fue determinar el comportamiento de 19 accesiones de Panicum maximum en suelos de mediana fertilidad. Se utilizó un diseño de bloques al azar con tres repeticiones y parcelas de 20 m². Las rotaciones (pastoreo racional simulado se efectuaron entre 60 y 70 días (época de seca y entre 32 y 40 días (época de lluvia. Se detectó una aceptable variabilidad entre tratamientos (70,7 %. Los indicadores más variables fueron: la disponibilidad, el porcentaje de utilización, el porcentaje de hojas y la altura de las plantas. Se aplicó un análisis de conglomerados y se formaron dos grupos: tipos gigantes (grupo 1 y tipos medianos (grupo 2. Los tratamientos del grupo 1 alcanzaron una disponibilidad media de 5,0 t MS/ha/rotación y superaron en 0,7 t MS/ha/rotación a los del grupo 2. Sin embargo, estos últimos mostraron menores síntomas de clorosis (34,0 %, fueron más tolerantes a los microorganismos patógenos (25,0 % y menos afectados por la sequía (42,0 %, y presentaron mayor vigor (3,8 como media de los tres años. Se concluye que en la variabilidad tuvieron un papel fundamental la disponibilidad, la altura, el porcentaje de hojas y el porcentaje de utilización. El resto de los indicadores fue relativamente poco variable, pero también permitió enjuiciar el comportamiento de estos materiales. Se recomiendan los tipos medianos CIH-6, SIH-810 y CIH-22 como variedades precomerciales para condiciones similares a las aquí utilizadas, e incluir el tipo gigante SIH-759 en ensayos en los que se emplee el corte o el pastoreo con mayor intensidad

Performance and nematode infection of ewe lambs on intensive rotational grazing with two different cultivars of Panicum maximum.

Science.gov (United States)

Costa, R L D; Bueno, M S; Veríssimo, C J; Cunha, E A; Santos, L E; Oliveira, S M; Spósito Filha, E; Otsuk, I P

2007-05-01

The daily live weight gain (DLWG), faecal nematode egg counts (FEC), and packed cell volume (PCV) of Suffolk, Ile de France and Santa Inês ewe lambs were evaluated fortnightly for 56 days in the dry season (winter) and 64 days in the rainy season (summer) of 2001-2002. The animals were distributed in two similar groups, one located on Aruana and the other on Tanzania grass (Panicum maximum), in rotational grazing system at the Instituto de Zootecnia, in Nova Odessa city (SP), Brazil. In the dry season, 24 one-year-old ewe lambs were used, eight of each breed, and there was no difference (p > 0.05) between grasses for DLWG (100 g/day), although the Suffolk had higher values (p < 0.05) than the other breeds. In the rainy season, with 33 six-month-old ewe lambs, nine Suffolk, eight Ile de France and 16 Santa Inês, the DLWG was not affected by breed, but it was twice as great (71 g/day, p < 0.05) on Aruana as on Tanzânia grass (30 g/day). The Santa Inês ewe lambs had the lowest FEC (p < 0.05) and the highest PCV (p < 0.05), confirming their higher resistance to Haemonchus contortus, the prevalent nematode in the rainy season. It was concluded that the best performance of ewe lambs on Aruana pastures in the rainy season is probably explained by their lower nematode infection owing to the better protein content of this grass (mean contents 11.2% crude protein in Aruana grass and 8.7% in Tanzania grass, p < 0.05) which may have improved the immunological system with the consequence that the highest PCV (p < 0.05) observed in those animals.

A laminar flame investigation of 2-butanone, and the combustion-related intermediates formed through its oxidation

KAUST Repository

Hemken, Christian

2016-06-28

2-Butanone (methyl ethyl ketone) is a high-octane next-generation biofuel candidate synthesized through microbiological pathways from biomass. The flame structure and species formed in 2-butanone combustion are of interest when further considering this compound for use as a fuel. Thus species profiles within a fuel-rich laminar premixed flat flame of 2-butanone were measured. Two experiments which used different facilities and measurement techniques were combined i.e. the first using electron ionization molecular-beam mass spectrometry (MBMS) and the second relied on synchrotron-generated vacuum UV photoionization MBMS. Very good agreement between both measurements was obtained. The experiments identified the formation of a number of toxic oxygenated intermediates such as methyl vinyl ketone (MVK) acetaldehyde and formaldehyde. 2- Butanone showed the lowest overall concentrations for species that could contribute to potentially hazardous volatile emissions underlining its attraction as a fuel also from this perspective.

A laminar flame investigation of 2-butanone, and the combustion-related intermediates formed through its oxidation

KAUST Repository

Hemken, Christian; Burke, Ultan; Graf, Isabelle; Ruwe, Lena; Park, Sungwoo; Sarathy, Mani; Heufer, K. Alexander; Kohse-Hö inghaus, Katharina

2016-01-01

2-Butanone (methyl ethyl ketone) is a high-octane next-generation biofuel candidate synthesized through microbiological pathways from biomass. The flame structure and species formed in 2-butanone combustion are of interest when further considering this compound for use as a fuel. Thus species profiles within a fuel-rich laminar premixed flat flame of 2-butanone were measured. Two experiments which used different facilities and measurement techniques were combined i.e. the first using electron ionization molecular-beam mass spectrometry (MBMS) and the second relied on synchrotron-generated vacuum UV photoionization MBMS. Very good agreement between both measurements was obtained. The experiments identified the formation of a number of toxic oxygenated intermediates such as methyl vinyl ketone (MVK) acetaldehyde and formaldehyde. 2- Butanone showed the lowest overall concentrations for species that could contribute to potentially hazardous volatile emissions underlining its attraction as a fuel also from this perspective.

Time-Domain Simulations of Transient Species in Experimentally Relevant Environments

Energy Technology Data Exchange (ETDEWEB)

Ueltschi, Tyler W.; Fischer, Sean A.; Apra, Edoardo; Tarnovsky, Alexander N.; Govind, Niranjan; El-Khoury, Patrick Z.; Hess, Wayne P.

2016-02-04

Simulating the spectroscopic properties of short-lived thermal and photochemical reaction intermediates and products is a challenging task, as these species often feature atypical molecular and electronic structures. The complex environments in which such species typically reside in practice add further complexity to the problem. Herein, we tackle this problem in silico using ab initio molecular dynamics (AIMD) simulations, employing iso-CHBr3, namely H(Br)C-Br-Br, as a prototypical system. This species was chosen because it features both a non-conventional C-Br-Br bonding pattern, as well as a strong dependence of its spectral features on the local environment in which it resides, as illustrated in recent experimental reports. The spectroscopic properties of iso-CHBr3 were measured by several groups that captured this transient intermediate in the photochemistry of CHBr3 in the gas phase, in rare gas matrices at 5K, and in solution under ambient laboratory conditions. We simulate the UV-Vis and IR spectra of iso-CHBr3 in all three media, including a Ne cluster (64 atoms) and a methylcyclohexane cage (14 solvent molecules) representative of the matrix isolated and solvated species. We exclusively perform fully quantum mechanical static and dynamic simulations. By comparing our condensed phase simulations to their experimental analogues, we stress the importance of (i) conformational sampling, even at cryogenic temperatures, and (ii) using a fully quantum mechanical description of both solute and bath to properly account for the experimental observables.

Taxation of Financial Intermediation Activities in Hong Kong

OpenAIRE

Jack M. Mintz; Stephen R. Richardson

2001-01-01

This paper discusses issues related to the taxation of financial intermediation in Hong Kong in the context of Hong Kong's position as a major regional financial centre. It first provides some background analysis as to the definition of financial intermediation and identification of the providers of financial services. This is then followed by a discussion of the principles of taxation applicable to financial intermediation, including a comparison of income taxes to consumption taxes. Some sp...

Immigration rates in fragmented landscapes--empirical evidence for the importance of habitat amount for species persistence.

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Thomas Püttker

Full Text Available BACKGROUND: The total amount of native vegetation is an important property of fragmented landscapes and is known to exert a strong influence on population and metapopulation dynamics. As the relationship between habitat loss and local patch and gap characteristics is strongly non-linear, theoretical models predict that immigration rates should decrease dramatically at low levels of remaining native vegetation cover, leading to patch-area effects and the existence of species extinction thresholds across fragmented landscapes with different proportions of remaining native vegetation. Although empirical patterns of species distribution and richness give support to these models, direct measurements of immigration rates across fragmented landscapes are still lacking. METHODOLOGY/PRINCIPAL FINDINGS: Using the Brazilian Atlantic forest marsupial Gray Slender Mouse Opossum (Marmosops incanus as a model species and estimating demographic parameters of populations in patches situated in three landscapes differing in the total amount of remaining forest, we tested the hypotheses that patch-area effects on population density are apparent only at intermediate levels of forest cover, and that immigration rates into forest patches are defined primarily by landscape context surrounding patches. As expected, we observed a positive patch-area effect on M. incanus density only within the landscape with intermediate forest cover. Density was independent of patch size in the most forested landscape and the species was absent from the most deforested landscape. Specifically, the mean estimated numbers of immigrants into small patches were lower in the landscape with intermediate forest cover compared to the most forested landscape. CONCLUSIONS/SIGNIFICANCE: Our results reveal the crucial importance of the total amount of remaining native vegetation for species persistence in fragmented landscapes, and specifically as to the role of variable immigration rates in

The giant African snail Achatina fulica as natural intermediate host of Angiostrongylus cantonensis in Pernambuco, northeast Brazil.

Science.gov (United States)

Thiengo, S C; Maldonado, A; Mota, E M; Torres, E J L; Caldeira, R; Carvalho, O S; Oliveira, A P M; Simões, R O; Fernandez, M A; Lanfredi, R M

2010-09-01

The human cases of eosinophilic meningitis recently reported from Brazil have focused the attention of the public health agencies on the role the introduced snail Achatina fulica plays as hosts of the metastrongylid nematodes. Determining the potential of this snail to host and develop infective larval stages of metastrongylids in the wild and identify the species harbored by them is crucial for designing effective control measures. Here we assess if A. fulica may act as intermediate host of A. cantonensis at the peridomiciliary areas of a patient's house from state of Pernambuco (PE), who was diagnosed with eosinophilic meningitis and a history of ingesting raw molluscs. Larvae obtained from naturally infected A. fulica were orally administered to Rattus norvegicus. The worms were collected from the pulmonary artery and brain, and were morphologically characterized and compared to the Japan isolate of A. cantonensis. Adult worms and infective L(3) larvae (PE isolate) recovered from A. fulica specimens were also analyzed by polymerase chain reaction and restriction fragment length polymorphism of ITS2 region from rDNA and compared to A. cantonensis (ES isolate), A. vasorum (MG isolate) and A. costaricensis (RS isolate). The large size of the spicules (greater than those observed in other species of Angiostrongylus) and the pattern of the bursal rays agree with the original species description by Chen (1935). Furthermore, the morphology of the PE isolate was similar to that of Japan isolate. The PCR-RFLP profiles obtained were distinctive among species and no variation in patterns was detected among adult individuals from A. cantonensis isolates from PE and ES. The importance of A. fulica as an intermediate host of eosinophilic menigoencepahlitis in Brazil is emphasized. 2010 Elsevier B.V. All rights reserved.

Intermediate-energy nuclear chemistry workshop

International Nuclear Information System (INIS)

Butler, G.W.; Giesler, G.C.; Liu, L.C.; Dropesky, B.J.; Knight, J.D.; Lucero, F.; Orth, C.J.

1981-05-01

This report contains the proceedings of the LAMPF Intermediate-Energy Nuclear Chemistry Workshop held in Los Alamos, New Mexico, June 23-27, 1980. The first two days of the Workshop were devoted to invited review talks highlighting current experimental and theoretical research activities in intermediate-energy nuclear chemistry and physics. Working panels representing major topic areas carried out indepth appraisals of present research and formulated recommendations for future research directions. The major topic areas were Pion-Nucleus Reactions, Nucleon-Nucleus Reactions and Nuclei Far from Stability, Mesonic Atoms, Exotic Interactions, New Theoretical Approaches, and New Experimental Techniques and New Nuclear Chemistry Facilities

Intermediate-energy nuclear chemistry workshop

Energy Technology Data Exchange (ETDEWEB)

Butler, G.W.; Giesler, G.C.; Liu, L.C.; Dropesky, B.J.; Knight, J.D.; Lucero, F.; Orth, C.J.

1981-05-01

This report contains the proceedings of the LAMPF Intermediate-Energy Nuclear Chemistry Workshop held in Los Alamos, New Mexico, June 23-27, 1980. The first two days of the Workshop were devoted to invited review talks highlighting current experimental and theoretical research activities in intermediate-energy nuclear chemistry and physics. Working panels representing major topic areas carried out indepth appraisals of present research and formulated recommendations for future research directions. The major topic areas were Pion-Nucleus Reactions, Nucleon-Nucleus Reactions and Nuclei Far from Stability, Mesonic Atoms, Exotic Interactions, New Theoretical Approaches, and New Experimental Techniques and New Nuclear Chemistry Facilities.

Hyperspectral signature analysis of three plant species to long-term hydrocarbon and heavy metal exposure

Science.gov (United States)

Lassalle, Guillaume; Credoz, Anthony; Fabre, Sophie; Hédacq, Rémy; Dubucq, Dominique; Elger, Arnaud

2017-10-01

Recent studies aim to exploit vegetation hyperspectral signature as an indicator of pipeline leakages and natural oil seepages by detecting changes in reflectance induced by oil exposure. In order to assess the feasibility of the method at larger spatial scale, a study has been carried out in a greenhouse on two tropical (Cenchrus alopecuroides and Panicum virgatum) and a temperate (Rubus fruticosus) species. Plants were grown on contaminated soil during 130 days, with concentrations up to 4.5 and 36 g.kg-1 for heavy metals and C10-C40 hydrocarbons respectively. Reflectance data (350-2500 nm) were acquired under artificial light from 1 to 60 days. All species showed an increase of reflectance in the visible (VIS, 400-750 nm) and short-wave infrared (SWIR, 1300-2500 nm) under experimental contaminants exposure. However, the responses were contrasted in the near-infrared (NIR, 750-1300 nm). 47 normalized vegetation indices were compared between treatments, and the most sensitive to contamination were retained. Same indices showed significant differences between treatments at leaf and plant scales. Indices related to plant pigments, plant water content and red-edge reflectance were particularly sensitive to soil contamination. In order to validate the selection of indices, hyperspectral measurements were performed outdoor at plant scale at the end of the experiment (130 days). Leaf samples were also collected for pigment analysis. Index selected at day 60 were still sensitive to soil contamination after 130 days. Significant changes in plant pigment composition were also observed. This study demonstrates the interest of hyperspectral data for oil exploration and environmental diagnosis.

The ARES High-level Intermediate Representation

Energy Technology Data Exchange (ETDEWEB)

Moss, Nicholas David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-03-03

The LLVM intermediate representation (IR) lacks semantic constructs for depicting common high-performance operations such as parallel and concurrent execution, communication and synchronization. Currently, representing such semantics in LLVM requires either extending the intermediate form (a signi cant undertaking) or the use of ad hoc indirect means such as encoding them as intrinsics and/or the use of metadata constructs. In this paper we discuss a work in progress to explore the design and implementation of a new compilation stage and associated high-level intermediate form that is placed between the abstract syntax tree and when it is lowered to LLVM's IR. This highlevel representation is a superset of LLVM IR and supports the direct representation of these common parallel computing constructs along with the infrastructure for supporting analysis and transformation passes on this representation.

Gasoline Engine Mechanics. Performance Objectives. Intermediate Course.

Science.gov (United States)

Jones, Marion

Several intermediate performance objectives and corresponding criterion measures are listed for each of six terminal objectives presented in this curriculum guide for an intermediate gasoline engine mechanics course at the secondary level. (For the beginning course guide see CE 010 947.) The materials were developed for a two-semester (2 hour…

Oxidative degradation of atenolol by heat-activated persulfate: Kinetics, degradation pathways and distribution of transformation intermediates.

Science.gov (United States)

Miao, Dong; Peng, Jianbiao; Zhou, Xiaohuan; Qian, Li; Wang, Mengjie; Zhai, Li; Gao, Shixiang

2018-05-17

Atenolol (ATL) has been widely detected in wastewater and aquatic environment. Although satisfactory removal of ATL from wastewater could be achieved, the mineralization ratio is usually low, which may result in the accumulation of its transformation products in the effluent and cause additional ecological risk to the environment. The aim of this study is to explore the effectiveness of heat activated persulfate (PS) in the removal of ATL from wastewater. Influencing factors including temperature, PS dosage, solution pH, existence of NO 3 - , Cl - , HCO 3 - and Suwannee river fulvic acid (SRFA) were examined. Complete removal of ATL was achieved within 40 min at pH 7.0 and 70 °C by using 0.5 mM PS. Inhibitive effects of HCO 3 - and FA had been observed on ATL oxidation, which was increased with the increase of their concentration. Sulfate radical (SO 4 - ) was determined as the main reactive species by quenching experiment. Eight intermediates produced in ATL degradation were identified, and four degradation pathways were proposed based on the analysis of mass spectrum and frontier electron densities. The distribution of major intermediates was influenced by reaction temperature. Hydroxylation intermediates and deamidation intermediate were the most prominent at 50 °C and 60 °C, respectively. All intermediates were completely degraded in 40 min except P134 at 70 °C. Effective removal of TOC (74.12%) was achieved with 0.5 mM PS, pH 7.0 and 70 °C after 240 min. The results proved that heat activation of PS is a promising method to remove organic pollutants in wastewater. Copyright © 2018 Elsevier Ltd. All rights reserved.

Descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham: III. Influencia de la densidad y diversidad de la macrofauna asociada Litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham: III. Influence of density and diversity of the associated macrofauna

Directory of Open Access Journals (Sweden)

Saray Sánchez

2010-03-01

Full Text Available Con el objetivo de determinar la descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala y su relación con la densidad y la diversidad de la macrofauna asociada, se realizó este experimento en la EEPF «Indio Hatuey». Esta se determinó como la pérdida de biomasa a través del tiempo, con relación al peso inicial. Para el estudio de la dinámica de la descomposición se utilizó el método de bolsas de hojarasca (litter bags. Se escogieron al azar cuatro bolsas a los 30, 60, 90, 120, 150, 180 y 210 días de situadas en el pastizal. En cada fecha de recolección, a la hojarasca remanente de cada bolsa se le determinó la población de macrofauna (organismos con diámetro mayor que 2 mm mediante la separación manual, y se calculó el valor promedio de la densidad (individuos/m², así como la abundancia proporcional (% para cada taxón. Se utilizó el análisis de correlación y regresión para conocer la interrelación entre las variables y los modelos de mejor ajuste. De acuerdo con los resultados se concluye que las condiciones de humedad y temperatura que genera el árbol en este sistema, así como la calidad de su hojarasca, posibilitan la presencia de una diversa y estable fauna asociada a las bolsas, la cual influyó en el proceso de descomposición.The trial was conducted at the EEPF «Indio Hatuey» in order to determine the litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala and its relation to the density and diversity of the associated macrofauna. It was determined as biomass loss through time, with regards to initial weight. For the study of the decomposition dynamics the litter bag method was used. Four bags were randomly chosen 30, 60, 90, 120, 150, 180 and 210 days after being placed in the pastureland. In each collection date, to the remnant litter of each bag, the macrofauna (organisms with diameter higher than 2 mm population was

Photosynthetic temperature responses of tree species in Rwanda: evidence of pronounced negative effects of high temperature in montane rainforest climax species

Science.gov (United States)

Vårhammar, Angelica; Wallin, Göran; McLean, Christopher M.; Dusenge, Mirindi Eric; Medlyn, Belinda E.; Hasper, Thomas B.; Nsabimana, Donat; Uddling, Johan

2015-04-01

The sensitivity of photosynthetic metabolism to temperature has been identified as a key uncertainty for projecting the magnitude of the terrestrial feedback on future climate change. While temperature responses of photosynthetic capacities have been comparatively well investigated in temperate species, the responses of tropical tree species remain unexplored. We compared the responses of seedlings of native cold-adapted tropical montane rainforest tree species to exotic warm-adapted plantation species, all growing in an intermediate temperature common garden in Rwanda. Leaf gas exchange responses to CO2 at different temperatures (20 - 40 C) were used to assess the temperature responses of biochemical photosynthetic capacities. Analyses revealed a lower optimum temperature for photosynthetic electron transport rates than for Rubisco carboxylation rates, along with lower electron transport optima in the native cold-adapted than in the exotic warm-adapted species. The photosynthetic optimum temperatures were generally exceeded by daytime peak leaf temperatures, in particular in the native montane rainforest climax species. This study thus provides evidence of pronounced negative effects of high temperature in tropical trees and indicates high susceptibility of montane rainforest climax species to future global warming. (Reference: New Phytologist, in press)

The Evolution of Functionally Redundant Species; Evidence from Beetles.

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Marten Scheffer

Full Text Available While species fulfill many different roles in ecosystems, it has been suggested that numerous species might actually share the same function in a near neutral way. So-far, however, it is unclear whether such functional redundancy really exists. We scrutinize this question using extensive data on the world's 4168 species of diving beetles. We show that across the globe these animals have evolved towards a small number of regularly-spaced body sizes, and that locally co-existing species are either very similar in size or differ by at least 35%. Surprisingly, intermediate size differences (10-20% are rare. As body-size strongly reflects functional aspects such as the food that these generalist predators can eat, these beetles thus form relatively distinct groups of functional look-a-likes. The striking global regularity of these patterns support the idea that a self-organizing process drives such species-rich groups to self-organize evolutionary into clusters where functional redundancy ensures resilience through an insurance effect.

Mapping Intermediality in Performance

NARCIS (Netherlands)

2010-01-01

Mapping Intermediality in Performance benadert het vraagstuk van intermedialiteit met betrekking tot performance (vooral theater) vanuit vijf verschillende invalshoeken: performativiteit en lichaam; tijd en ruimte; digitale cultuur en posthumanisme; netwerken; pedagogiek en praxis. In deze boeiende

How to be a good neighbour: Facilitation and competition between two co-flowering species.

Science.gov (United States)

Mesgaran, Mohsen B; Bouhours, Juliette; Lewis, Mark A; Cousens, Roger D

2017-06-07

Empirical evidence suggests that co-flowering species can facilitate each other through shared pollinators. However, the extent to which one co-flowering species can relieve pollination limitation of another while simultaneously competing for abiotic resource has rarely been examined. Using a deterministic model we explored the demographic outcome for one ("focal") species of its co-occurrence with a species that shares pollinators and competes for both pollinator visitation and abiotic resources. In this paper we showed how the overall impact can be positive or negative, depending on the balance between enhanced fertilization versus increased competition. Our model could predict the density of co-flowering species that will maximize the pollination rate of the focal species by attracting pollinators. Because that density will also give rise to competitive effects, a lower density of co-flowering species is required for optimizing the trade-off between enhanced fertilization and competition so as to give the maximum possible facilitation of reproduction in the focal species. Results were qualitatively different when we considered attractiveness of the co-flowering species, as opposed to its density, because attractiveness, unlike density, had no effect on competition for abiotic resources. Whereas unattractive neighbours would not bring in pollinators, very attractive neighbours would captivate pollinators, not sharing them with the focal species. Thus optimal benefit to the focal species came at intermediate levels of attractiveness in the co-flowering species. This intermediate level of attractiveness in co-flowering species simultaneously maximized pollination and overall facilitation of reproduction for the focal species. The likelihood of facilitation was predicted to decline with the selfing rate of the focal species, revealing an indirect cost for an inbreeding mating system. Whether a co-flowering species can be facilitative depends on the way pollinators

Divergent mating preferences and nuptial coloration in sibling species of cichlid fish

NARCIS (Netherlands)

Sluijs, Inke van der

2008-01-01

Mate choice by female cichlid fish from Lake Victoria plays an important role in speciation and the maintenance of species. Females are expected to select against males that are intermediate in their phenotype during the process of speciation driven by sexual selection. To test this, we hybridized

Species richness of vascular plants, bryophytes, and lichens along an altitudinal gradient in western Norway

Science.gov (United States)

Grytnes, John Arvid; Heegaard, Einar; Ihlen, Per G.

2006-05-01

Species richness patterns of ground-dwelling vascular plants, bryophytes, and lichens were compared along an altitudinal gradient (310-1135 m a.s.l.), in western Norway. Total species richness peaked at intermediate altitudes, vascular plant species richness peaked immediately above the forest limit (at 600-700 m a.s.l.), bryophyte species richness had no statistically significant trend, whereas lichen richness increased from the lowest point and up to the forest limit, with no trend above. It is proposed that the pattern in vascular plant species richness is enhanced by an ecotone effect. Bryophyte species richness responds to local scale factors whereas the lichen species richness may be responding to the shading from the forest trees.

What Makes a Bacterial Species Pathogenic?:Comparative Genomic Analysis of the Genus Leptospira.

Science.gov (United States)

Fouts, Derrick E; Matthias, Michael A; Adhikarla, Haritha; Adler, Ben; Amorim-Santos, Luciane; Berg, Douglas E; Bulach, Dieter; Buschiazzo, Alejandro; Chang, Yung-Fu; Galloway, Renee L; Haake, David A; Haft, Daniel H; Hartskeerl, Rudy; Ko, Albert I; Levett, Paul N; Matsunaga, James; Mechaly, Ariel E; Monk, Jonathan M; Nascimento, Ana L T; Nelson, Karen E; Palsson, Bernhard; Peacock, Sharon J; Picardeau, Mathieu; Ricaldi, Jessica N; Thaipandungpanit, Janjira; Wunder, Elsio A; Yang, X Frank; Zhang, Jun-Jie; Vinetz, Joseph M

2016-02-01

Leptospirosis, caused by spirochetes of the genus Leptospira, is a globally widespread, neglected and emerging zoonotic disease. While whole genome analysis of individual pathogenic, intermediately pathogenic and saprophytic Leptospira species has been reported, comprehensive cross-species genomic comparison of all known species of infectious and non-infectious Leptospira, with the goal of identifying genes related to pathogenesis and mammalian host adaptation, remains a key gap in the field. Infectious Leptospira, comprised of pathogenic and intermediately pathogenic Leptospira, evolutionarily diverged from non-infectious, saprophytic Leptospira, as demonstrated by the following computational biology analyses: 1) the definitive taxonomy and evolutionary relatedness among all known Leptospira species; 2) genomically-predicted metabolic reconstructions that indicate novel adaptation of infectious Leptospira to mammals, including sialic acid biosynthesis, pathogen-specific porphyrin metabolism and the first-time demonstration of cobalamin (B12) autotrophy as a bacterial virulence factor; 3) CRISPR/Cas systems demonstrated only to be present in pathogenic Leptospira, suggesting a potential mechanism for this clade's refractoriness to gene targeting; 4) finding Leptospira pathogen-specific specialized protein secretion systems; 5) novel virulence-related genes/gene families such as the Virulence Modifying (VM) (PF07598 paralogs) proteins and pathogen-specific adhesins; 6) discovery of novel, pathogen-specific protein modification and secretion mechanisms including unique lipoprotein signal peptide motifs, Sec-independent twin arginine protein secretion motifs, and the absence of certain canonical signal recognition particle proteins from all Leptospira; and 7) and demonstration of infectious Leptospira-specific signal-responsive gene expression, motility and chemotaxis systems. By identifying large scale changes in infectious (pathogenic and intermediately pathogenic

What Makes a Bacterial Species Pathogenic?:Comparative Genomic Analysis of the Genus Leptospira.

Directory of Open Access Journals (Sweden)

Derrick E Fouts

2016-02-01

Full Text Available Leptospirosis, caused by spirochetes of the genus Leptospira, is a globally widespread, neglected and emerging zoonotic disease. While whole genome analysis of individual pathogenic, intermediately pathogenic and saprophytic Leptospira species has been reported, comprehensive cross-species genomic comparison of all known species of infectious and non-infectious Leptospira, with the goal of identifying genes related to pathogenesis and mammalian host adaptation, remains a key gap in the field. Infectious Leptospira, comprised of pathogenic and intermediately pathogenic Leptospira, evolutionarily diverged from non-infectious, saprophytic Leptospira, as demonstrated by the following computational biology analyses: 1 the definitive taxonomy and evolutionary relatedness among all known Leptospira species; 2 genomically-predicted metabolic reconstructions that indicate novel adaptation of infectious Leptospira to mammals, including sialic acid biosynthesis, pathogen-specific porphyrin metabolism and the first-time demonstration of cobalamin (B12 autotrophy as a bacterial virulence factor; 3 CRISPR/Cas systems demonstrated only to be present in pathogenic Leptospira, suggesting a potential mechanism for this clade's refractoriness to gene targeting; 4 finding Leptospira pathogen-specific specialized protein secretion systems; 5 novel virulence-related genes/gene families such as the Virulence Modifying (VM (PF07598 paralogs proteins and pathogen-specific adhesins; 6 discovery of novel, pathogen-specific protein modification and secretion mechanisms including unique lipoprotein signal peptide motifs, Sec-independent twin arginine protein secretion motifs, and the absence of certain canonical signal recognition particle proteins from all Leptospira; and 7 and demonstration of infectious Leptospira-specific signal-responsive gene expression, motility and chemotaxis systems. By identifying large scale changes in infectious (pathogenic and intermediately

Ecophysiological responses of two herbaceous species to prescribed burning, alone or in combination with overstory thinning.

Science.gov (United States)

Huang, Jianjun; Boerner, Ralph E J; Rebbeck, Joanne

2007-05-01

The oak-rich deciduous forests of the central Appalachian Mountains of eastern North America have changed significantly since the onset of effective fire suppression early in the 20th century. Those changes have resulted in progressively decreasing light and nutrient supplies to herbaceous perennial understory species. Application of ecological restoration treatments such as reintroduction of frequent dormant-season fire and overstory thinning to pre-suppression density often increase light, soil temperature and moisture, and short-term nutrient availability to pre-suppression levels. To persist in this environment, perennial understory herbs must be able to acclimate phenotypically to the very different resource supply combinations present with and without fire suppression. As part of a larger study of the response of the long-lived herbaceous perennials Desmodium nudiflorum and Panicum boscii to ecosystem restoration treatments in Ohio mixed-oak forests, this study examined the ecophysiological effects of prescribed burning (B) and the combination of burning and thinning (T + B) in mixed-oak forests in southern Ohio. Control (C) plants had significantly lower maximum photosynthetic rate (A(max)) than those in the treated plots. The enhancement of A(max) averaged 26.7% and 52.7% in the B and T + B treatments, respectively. Plants from the T + B plots had higher quantum yield, stomatal conductance, and photosynthetic nutrient use efficiency than B and C plants. B plants had greater intrinsic water use efficiency (WUE) than plants in the C or T + B treatments. Light saturation point (LSP), light compensation point (LCP), and "dark" respiration (DR) did not differ among treatments. Photosynthetic parameters did vary significantly between the species, but no significant treatment × species interactions were detected. Our results support the hypothesis that prescribed burning, especially when combined with overstory thinning, in these perennial herbs can result in

On ternary species mixing and combustion in isotropic turbulence at high pressure

Science.gov (United States)

Lou, Hong; Miller, Richard S.

2004-05-01

Effects of Soret and Dufour cross-diffusion, whereby both concentration and thermal diffusion occur in the presence of mass fraction, temperature, and pressure gradients, are investigated in the context of both binary and ternary species mixing and combustion in isotropic turbulence at large pressure. The compressible flow formulation is based on a cubic real-gas state equation, and includes generalized forms for heat and mass diffusion derived from nonequilibrium thermodynamics and fluctuation theory. A previously derived formulation of the generalized binary species heat and mass fluxes is first extended to the case of ternary species, and appropriate treatment of the thermal and mass diffusion factors is described. Direct numerical simulations (DNS) are then conducted for both binary and ternary species mixing and combustion in stationary isotropic turbulence. Mean flow temperatures and pressures of =700 K and =45 atm are considered to ensure that all species mixtures remain in the supercritical state such that phase changes do not occur. DNS of ternary species systems undergoing both pure mixing and a simple chemical reaction of the form O2+N2→2NO are then conducted. It is shown that stationary scalar states previously observed for binary mixing persist for the ternary species problem as well; however, the production and magnitude of the scalar variance is found to be altered for the intermediate molecular weight species as compared to the binary species case. The intermediate molecular weight species produces a substantially smaller scalar variance than the remaining species for all flows considered. For combustion of nonstoichiometric mixtures, a binary species mixture, characterized by stationary scalar states, results at long times after the lean reactant is depleted. The form of this final scalar distribution is observed to be similar to that found in the binary flow situation. A series of lower resolution simulations for a variety of species is then

Genetic variability and identification of the intermediate snail hosts of Schistosoma mansoni

Directory of Open Access Journals (Sweden)

Teofânia HDA Vidigal

1998-01-01

Full Text Available Studies based on shell or reproductive organ morphology and genetic considerations suggest extensive intraspecific variation in Biomphalaria snails. The high variability at the morphological and genetic levels, as well as the small size of some specimens and similarities between species complicate the correct identification of these snails. Here we review our work using methods based on polymerase chain reaction (PCR amplification for analysis of genetic variation and identification of Biomphalaria snails from Brazil, Argentina, Uruguay and Paraguay. Arbitrarily primed-PCR revealed that the genome of B. glabrata exihibits a remarkable degree of intraespecific polymorphism. Low stringency-PCR using primers for 18S rRNA permited the identification of B. glabrata, B. tenagophila and B. occidentalis. The study of individuals obtained from geographically distinct populations exhibits significant intraspecific DNA polymorphism, however specimens from the same species, exhibit some species specific LSPs. We also showed that PCR-restriction fragment of length polymorphism of the internal transcribed spacer region of Biomphalaria rDNA, using DdeI permits the differentiation of the three intermediate hosts of Schistosoma mansoni. The molecular biological techniques used in our studies are very useful for the generation of new knowledge concerning the systematics and population genetics of Biomphalaria snails.

Ecological aspects study of replacement intercropping patterns of Soybean (Glycine max L. and Millet (Panicum miliaceum L.

Directory of Open Access Journals (Sweden)

Goudarz Ahmadvand

2016-03-01

Full Text Available Intercropping is considered for increasing and stability of yield in per unit. In order to study the effects of soybean (Glycine max L. and millet (Panicum miliaceum L. replacement intercropping on agronomic traits, diversity of weeds and soil biological activity, an experiment was conducted at the Research Station of Agricultural Faculty, of Bu-Ali Sina University, in 2014. The experiment was carried out as a randomized complete block design with three replications. The replacement intercropping series consisted of monoculture of soybean, monoculture of millet, 75% soybean+ 25% millet, 50% soybean+ 50% millet and 25% soybean+ 75% millet. The results showed that the highest seed yield of 219.8 and 171.9 gm-2 belonged to monoculture of soybean and monoculture of millet, respectively. Intercropping reduced maximum leaf area index of soybean and millet but leaf chlorophyll content of soybean and millet were increased. The highest number of pods per plant, number of seeds per plant in soybean and panicle number per plant in millet were obtained in 50S:50M ratio. Mean soil respiration rate in intercropping treatments was 4 and 8 % higher than the monoculture of soybean and millet, respectively. Intercropping patterns of 50S:50M and 25S:75M were successful in reducing weed plant density and diversity in comparison with soybean monoculture. Results showed that in all intercropping treatments, land equivalent ratio was more than one. Maximum value of land equivalent ratio (2.20 was achieved in 50S:50M treatment. Soybean and millet intercropping at different levels of replacement, didn’t have actual yield loss. Calculating the aggressivity showed that millet was more dominate than soybean. The maximum relative crowding coefficient of soybean was observed in 75S:25M, however that of millet was obtained in 25S:75M and 50S:50M intercroppings indicating that millet is more competitor than soybean.

The Intermediate Neutrino Program

CERN Document Server

Adams, C.; Ankowski, A.M.; Asaadi, J.A.; Ashenfelter, J.; Axani, S.N.; Babu, K.; Backhouse, C.; Band, H.R.; Barbeau, P.S.; Barros, N.; Bernstein, A.; Betancourt, M.; Bishai, M.; Blucher, E.; Bouffard, J.; Bowden, N.; Brice, S.; Bryan, C.; Camilleri, L.; Cao, J.; Carlson, J.; Carr, R.E.; Chatterjee, A.; Chen, M.; Chen, S.; Chiu, M.; Church, E.D.; Collar, J.I.; Collin, G.; Conrad, J.M.; Convery, M.R.; Cooper, R.L.; Cowen, D.; Davoudiasl, H.; de Gouvea, A.; Dean, D.J.; Deichert, G.; Descamps, F.; DeYoung, T.; Diwan, M.V.; Djurcic, Z.; Dolinski, M.J.; Dolph, J.; Donnelly, B.; Dwyer, D.A.; Dytman, S.; Efremenko, Y.; Everett, L.L.; Fava, A.; Figueroa-Feliciano, E.; Fleming, B.; Friedland, A.; Fujikawa, B.K.; Gaisser, T.K.; Galeazzi, M.; Galehouse, D.C.; Galindo-Uribarri, A.; Garvey, G.T.; Gautam, S.; Gilje, K.E.; Gonzalez-Garcia, M.; Goodman, M.C.; Gordon, H.; Gramellini, E.; Green, M.P.; Guglielmi, A.; Hackenburg, R.W.; Hackenburg, A.; Halzen, F.; Han, K.; Hans, S.; Harris, D.; Heeger, K.M.; Herman, M.; Hill, R.; Holin, A.; Huber, P.; Jaffe, D.E.; Johnson, R.A.; Joshi, J.; Karagiorgi, G.; Kaufman, L.J.; Kayser, B.; Kettell, S.H.; Kirby, B.J.; Klein, J.R.; Kolomensky, Yu. G.; Kriske, R.M.; Lane, C.E.; Langford, T.J.; Lankford, A.; Lau, K.; Learned, J.G.; Ling, J.; Link, J.M.; Lissauer, D.; Littenberg, L.; Littlejohn, B.R.; Lockwitz, S.; Lokajicek, M.; Louis, W.C.; Luk, K.; Lykken, J.; Marciano, W.J.; Maricic, J.; Markoff, D.M.; Martinez Caicedo, D.A.; Mauger, C.; Mavrokoridis, K.; McCluskey, E.; McKeen, D.; McKeown, R.; Mills, G.; Mocioiu, I.; Monreal, B.; Mooney, M.R.; Morfin, J.G.; Mumm, P.; Napolitano, J.; Neilson, R.; Nelson, J.K.; Nessi, M.; Norcini, D.; Nova, F.; Nygren, D.R.; Orebi Gann, G.D.; Palamara, O.; Parsa, Z.; Patterson, R.; Paul, P.; Pocar, A.; Qian, X.; Raaf, J.L.; Rameika, R.; Ranucci, G.; Ray, H.; Reyna, D.; Rich, G.C.; Rodrigues, P.; Romero, E.Romero; Rosero, R.; Rountree, S.D.; Rybolt, B.; Sanchez, M.C.; Santucci, G.; Schmitz, D.; Scholberg, K.; Seckel, D.; Shaevitz, M.; Shrock, R.; Smy, M.B.; Soderberg, M.; Sonzogni, A.; Sousa, A.B.; Spitz, J.; St. John, J.M.; Stewart, J.; Strait, J.B.; Sullivan, G.; Svoboda, R.; Szelc, A.M.; Tayloe, R.; Thomson, M.A.; Toups, M.; Vacheret, A.; Vagins, M.; Van de Water, R.G.; Vogelaar, R.B.; Weber, M.; Weng, W.; Wetstein, M.; White, C.; White, B.R.; Whitehead, L.; Whittington, D.W.; Wilking, M.J.; Wilson, R.J.; Wilson, P.; Winklehner, D.; Winn, D.R.; Worcester, E.; Yang, L.; Yeh, M.; Yokley, Z.W.; Yoo, J.; Yu, B.; Yu, J.; Zhang, C.

2015-01-01

The US neutrino community gathered at the Workshop on the Intermediate Neutrino Program (WINP) at Brookhaven National Laboratory February 4-6, 2015 to explore opportunities in neutrino physics over the next five to ten years. Scientists from particle, astroparticle and nuclear physics participated in the workshop. The workshop examined promising opportunities for neutrino physics in the intermediate term, including possible new small to mid-scale experiments, US contributions to large experiments, upgrades to existing experiments, R&D plans and theory. The workshop was organized into two sets of parallel working group sessions, divided by physics topics and technology. Physics working groups covered topics on Sterile Neutrinos, Neutrino Mixing, Neutrino Interactions, Neutrino Properties and Astrophysical Neutrinos. Technology sessions were organized into Theory, Short-Baseline Accelerator Neutrinos, Reactor Neutrinos, Detector R&D and Source, Cyclotron and Meson Decay at Rest sessions.This report summ...

Insights into the relationships of Palearctic and Nearctic lymnaeids (Mollusca : Gastropoda by rDNA ITS-2 sequencing and phylogeny of stagnicoline intermediate host species of Fasciola hepatica

Directory of Open Access Journals (Sweden)

Bargues M.D.

2003-09-01

stagnicolines, (iii the link between the North American stagnicolines-L. occulta group with Galba truncatula, and (iii the location of the L. p. turricula genotype from Poland closer to L. p. palustris than to other European L. p. turricula genotypes. The Palaearctic species occulta is included in the genus Catascopia, together with the Nearctic species catascopium, emarginata and elodes. The results suggest a potential of transmission capacity for C. occulta higher than that of other European stagnicolines or Omphiscola glabra. The relatively low genetic distances between C. occulta and G. truncatula and the clustering of both species in the same clade suggest that C.occulta may be potentially considered as the second lymnaeid intermediate host species of F. hepatica in importance in eastern and northern Europe, and probably also western and central Asia, after G. truncatula. L. p. turricula may be considered as a potential secondary vector of F. hepatica, at a level similar tot that of L.p. palustris.

Intermediate Inflation or Late Time Acceleration?

International Nuclear Information System (INIS)

Sanyal, A.K.

2008-01-01

The expansion rate of intermediate inflation lies between the exponential and power law expansion but corresponding accelerated expansion does not start at the onset of cosmological evolution. Present study of intermediate inflation reveals that it admits scaling solution and has got a natural exit form it at a later epoch of cosmic evolution, leading to late time acceleration. The corresponding scalar field responsible for such feature is also found to behave as a tracker field for gravity with canonical kinetic term.

On financial equilibrium with intermediation costs

DEFF Research Database (Denmark)

Markeprand, Tobias Ejnar

2008-01-01

This paper studies the set of competitive equilibria in financial economies with intermediation costs. We consider an arbitrary dividend structure, which includes options and equity with limited liabilities.We show a general existence result and upper-hemi continuity of the equilibrium correspond......This paper studies the set of competitive equilibria in financial economies with intermediation costs. We consider an arbitrary dividend structure, which includes options and equity with limited liabilities.We show a general existence result and upper-hemi continuity of the equilibrium...

Intermediate product selection and blending in the food processing industry

DEFF Research Database (Denmark)

Kilic, Onur A.; Akkerman, Renzo; van Donk, Dirk Pieter

2013-01-01

This study addresses a capacitated intermediate product selection and blending problem typical for two-stage production systems in the food processing industry. The problem involves the selection of a set of intermediates and end-product recipes characterising how those selected intermediates...

Intermediate product selection and blending in the food processing industry

NARCIS (Netherlands)

Kilic, Onur A.; Akkerman, Renzo; van Donk, Dirk Pieter; Grunow, Martin

2013-01-01

This study addresses a capacitated intermediate product selection and blending problem typical for two-stage production systems in the food processing industry. The problem involves the selection of a set of intermediates and end-product recipes characterising how those selected intermediates are

Biodegradation of nicotine by a novel nicotine-degrading bacterium, Pseudomonas plecoglossicida TND35 and its new biotransformation intermediates.

Science.gov (United States)

Raman, Gurusamy; Mohan, KasiNadar; Manohar, Venkat; Sakthivel, Natarajan

2014-02-01

Tobacco wastes that contain nicotine alkaloids are harmful to human health and the environment. In the investigation, a novel nicotine-biodegrading bacterium TND35 was isolated and identified as Pseudomonas plecoglossicida on the basis of phenotypic, biochemical characteristics and 16S rRNA sequence homology. We have studied the nicotine biodegradation potential of strain TND35 by detecting the intermediate metabolites using an array of approaches such as HPLC, GC-MS, NMR and FT-IR. Biotransformation metabolites, N-methylmyosmine, 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB) and other three new intermediate metabolites namely, 3,5-bis (1-methylpyrrolidin-2-yl) pyridine, 2,3-dihydro-1-methyl-5-(pyridin-3-yl)-1H-pyrrol-2-ol and 5-(pyridin-3-yl)-1H-pyrrol-2(3H)-one have been identified. Interestingly, these intermediate metabolites suggest that the strain TND35 employs a novel nicotine biodegradation pathway, which is different from the reported pathways of Aspergillus oryzae 112822, Arthrobacter nicotinovorans pAO1, Agrobacterium tumefaciens S33 and other species of Pseudomonas. The metabolite, HPB reported in this study can also be used as biochemical marker for tobacco related cancer studies.

An ecological study of Bithynia snails, the first intermediate host of Opisthorchis viverrini in northeast Thailand.

Science.gov (United States)

Wang, Yi-Chen; Ho, Richard Cheng Yong; Feng, Chen-Chieh; Namsanor, Jutamas; Sithithaworn, Paiboon

2015-01-01

Infection with the food-borne trematodiasis, liver fluke Opisthorchis viverrini, is a major public health concern in Southeast Asia. While epidemiology and parasitic incidence in humans are well studied, ecological information on the O. viverrini intermediate hosts remains limited. This study aimed to investigate the factors affecting the distribution and abundance of the first intermediate host, Bithynia siamensis goniomphalos snails. Water quality and snails were sampled in 31 sites in Muang District, Khon Kaen Province, Thailand from June 2012 to January 2013 to characterize the B.s. goniomphalos snail habitats. Species relative abundance and Shannon's diversity and evenness indices were employed to describe snail compositions and diversities across different habitat types. Statistical analyses were conducted to examine the extent to which the water quality variables and species interactions account for the relative abundance of B.s. goniomphalos snails. The results showed that the freshwater habitats of ponds, streams and rice paddies possessed significantly different abiotic water qualities, with water temperature and pH showing distinct statistical differences (P<0.05). Different habitats had different snail diversity and species evenness, with high B.s. goniomphalos snail abundance at rice paddy habitats. The differences in snail abundance might be due to the distinct sets of abiotic water qualities associated with each habitat types. The relative abundance of B.s. goniomphalos snails was found to be negatively correlated with that of Filopaludina martensi martensi snails (r=-0.46, P<0.05), underscoring the possible influence of species interaction on B.s. goniomphalos snail population. Field work observations revealed that rice planting seasons and irrigation could regulate snail population dynamics at rice paddy habitats. This study provides new ecological insights into the factors affecting Bithynia snail distribution and abundance. It bridges the

Future possibilities with intermediate-energy neutron beams

International Nuclear Information System (INIS)

Brady, F.P.

1987-01-01

Future possibilities for using neutrons of intermediate energies (50 - 200 MeV) as a probe of the nucleus are discussed. Some of the recent thinking concerning a systematic approach for studying elastic and inelastic scattering of electrons and hadrons and the important role of medium- and intermediate-energy neutrons in such a programme is reviewed. The advantages of neutrons in this energy range over neutrons with lower energies and over intermediate-energy pions for determining nuclear-transition and ground state densities, and for distinguishing proton from neutron density (isovector sensitivity), are noted. The important role of (n,p) charge exchange reactions in nuclear excitation studies is also reviewed. Experimental methods for utilizing neutrons as probes in elastic, inelastic, and charge exchange studies at these energies are discussed

Identification and overexpression of a Knotted1-like transcription factor in switchgrass (Panicum virgatum L. for lignocellulosic feedstock improvement

Directory of Open Access Journals (Sweden)

Wegi eWuddineh

2016-04-01

Full Text Available High biomass production and wide adaptation has made switchgrass (Panicum virgatum L. an important candidate lignocellulosic bioenergy crop. One major limitation of this and other lignocellulosic feedstocks is the recalcitrance of complex carbohydrates to hydrolysis for conversion to biofuels. Lignin is the major contributor to recalcitrance as it limits the accessibility of cell wall carbohydrates to enzymatic breakdown into fermentable sugars. Therefore, genetic manipulation of the lignin biosynthesis pathway is one strategy to reduce recalcitrance. Here, we identified a switchgrass Knotted1 transcription factor, PvKN1, with the aim of genetically engineering switchgrass for reduced biomass recalcitrance for biofuel production. Gene expression of the endogenous PvKN1 gene was observed to be highest in young inflorescences and stems. Ectopic overexpression of PvKN1 in switchgrass altered growth, especially in early developmental stages. Transgenic lines had reduced expression of most lignin biosynthetic genes accompanied by a reduction in lignin content suggesting the involvement of PvKN1 in the broad regulation of the lignin biosynthesis pathway. Moreover, the reduced expression of the Gibberellin 20-oxidase (GA20ox gene in tandem with the increased expression of Gibberellin 2-oxidase (GA2ox genes in transgenic PvKN1 lines suggest that PvKN1 may exert regulatory effects via modulation of GA signalling. Furthermore, overexpression of PvKN1 altered the expression of cellulose and hemicellulose biosynthetic genes and increased sugar release efficiency in transgenic lines. Our results demonstrated that switchgrass PvKN1 is a putative ortholog of maize KN1 that is linked to plant lignification and cell wall and development traits as a major regulatory gene. Therefore, targeted overexpression of PvKN1 in bioenergy feedstocks may provide one feasible strategy for reducing biomass recalcitrance and simultaneously improving plant growth characteristics.

Unfolding Simulations of Holomyoglobin from Four Mammals: Identification of Intermediates and β-Sheet Formation from Partially Unfolded States

DEFF Research Database (Denmark)

Dasmeh, Pouria; Kepp, Kasper Planeta

2013-01-01

simulations of holoMb and the first comparative study of unfolding of protein orthologs from different species (sperm whale, pig, horse, and harbor seal). We also provide new interpretations of experimental mean molecular ellipticities of myoglobin intermediates, notably correcting for random coil and number...... of helices in intermediates. The simulated holoproteins at 310 K displayed structures and dynamics in agreement with crystal structures (Rg ,1.48–1.51 nm, helicity ,75%). At 400 K, heme was not lost, but some helix loss was observed in pig and horse, suggesting that these helices are less stable......Myoglobin (Mb) is a centrally important, widely studied mammalian protein. While much work has investigated multi-step unfolding of apoMb using acid or denaturant, holomyoglobin unfolding is poorly understood despite its biological relevance. We present here the first systematic unfolding...

Respostas morfológicas do capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia-1 irrigado à intensidade de desfolha sob lotação rotacionada Morphological responses of irrigated Tanzaniagrass (Panicum Maximum Jacq. cv. Tanzania-1 to grazing intensity under rotational stocking

Directory of Open Access Journals (Sweden)

Alexandre Carneiro Leão de Mello

2004-04-01

Full Text Available Objetivando quantificar respostas morfológicas de dosséis de capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia-1 sob três intensidades de pastejo, lotação rotacionada e irrigação, foi conduzido um experimento em delineamento experimental de blocos completos casualizados com quatro repetições. Os tratamentos foram três intensidades de pastejo, representados pelas quantidades de massa seca verde residual pós-pastejo (T1=1000; T2=2500 e T3=4000 kg MSV/ha. Durante oito ciclos de pastejo (rebrotas de 33 dias após três dias de pastejo em cada ciclo, foram realizadas avaliações de altura média do dossel, índice de área foliar (IAF, interceptação luminosa (IL e ângulos foliares médios, em quatro dias dentro do período de rebrota (1, 11, 22 e 33 dias após a saída dos animais. A análise de correlações parciais indicou correlações entre altura e IL, bem como entre IAF e IL. Com o progresso da estação de pastejo, da primavera-verão para outono-inverno, houve reduções nos valores de IAF médio. Valores médios de IAF crítico (95% IL de 3,6 (T1, 4,0 (T2 e 4,5 (T3, foram alcançados por volta do 22º dia das rebrotas. A maior intensidade de pastejo (menor resíduo alterou a estrutura da pastagem no que diz respeito à arquitetura do dossel, evidenciada pela redução nos ângulos foliares médios (folhas mais horizontais ao longo das estações, com plantas passando a interceptar mais luz por unidade de área foliar. Os IAFs críticos medidos sugerem a necessidade de períodos de descanso menores que 33 dias em pastos de capim-Tanzânia, quando submetido a pastejo intensivo sob lotação rotacionada e irrigação.The objective of this research was to quantify morphological responses of Tanzania grass (Panicum maximum Jacq. cv. Tanzania-1 under three grazing intensities in an irrigated, rotationally stocked setting. Treatments consisted of three grazing intensities represented by three post-graze forage masses (T1=1,000; T

Chemical Exchange Saturation Transfer in Chemical Reactions: A Mechanistic Tool for NMR Detection and Characterization of Transient Intermediates.

Science.gov (United States)

Lokesh, N; Seegerer, Andreas; Hioe, Johnny; Gschwind, Ruth M

2018-02-07

The low sensitivity of NMR and transient key intermediates below detection limit are the central problems studying reaction mechanisms by NMR. Sensitivity can be enhanced by hyperpolarization techniques such as dynamic nuclear polarization or the incorporation/interaction of special hyperpolarized molecules. However, all of these techniques require special equipment, are restricted to selective reactions, or undesirably influence the reaction pathways. Here, we apply the chemical exchange saturation transfer (CEST) technique for the first time to NMR detect and characterize previously unobserved transient reaction intermediates in organocatalysis. The higher sensitivity of CEST and chemical equilibria present in the reaction pathway are exploited to access population and kinetics information on low populated intermediates. The potential of the method is demonstrated on the proline-catalyzed enamine formation for unprecedented in situ detection of a DPU stabilized zwitterionic iminium species, the elusive key intermediate between enamine and oxazolidinones. The quantitative analysis of CEST data at 250 K revealed the population ratio of [Z-iminium]/[exo-oxazolidinone] 0.02, relative free energy +8.1 kJ/mol (calculated +7.3 kJ/mol), and free energy barrier of +45.9 kJ/mol (ΔG ⧧ calc. (268 K) = +42.2 kJ/mol) for Z-iminium → exo-oxazolidinone. The findings underpin the iminium ion participation in enamine formation pathway corroborating our earlier theoretical prediction and help in better understanding. The reliability of CEST is validated using 1D EXSY-build-up techniques at low temperature (213 K). The CEST method thus serves as a new tool for mechanistic investigations in organocatalysis to access key information, such as chemical shifts, populations, and reaction kinetics of intermediates below the standard NMR detection limit.

The Intermediate Neutrino Program

Energy Technology Data Exchange (ETDEWEB)

Adams, C.; et al.

2015-03-23

The US neutrino community gathered at the Workshop on the Intermediate Neutrino Program (WINP) at Brookhaven National Laboratory February 4-6, 2015 to explore opportunities in neutrino physics over the next five to ten years. Scientists from particle, astroparticle and nuclear physics participated in the workshop. The workshop examined promising opportunities for neutrino physics in the intermediate term, including possible new small to mid-scale experiments, US contributions to large experiments, upgrades to existing experiments, R&D plans and theory. The workshop was organized into two sets of parallel working group sessions, divided by physics topics and technology. Physics working groups covered topics on Sterile Neutrinos, Neutrino Mixing, Neutrino Interactions, Neutrino Properties and Astrophysical Neutrinos. Technology sessions were organized into Theory, Short-Baseline Accelerator Neutrinos, Reactor Neutrinos, Detector R&D and Source, Cyclotron and Meson Decay at Rest sessions.This report summarizes discussion and conclusions from the workshop.

The Intermediate Neutrino Program

Energy Technology Data Exchange (ETDEWEB)

Adams, C. [Yale Univ., New Haven, CT (United States); Alonso, J. R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Ankowski, A. M. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Asaadi, J. A. [Syracuse Univ., NY (United States); Ashenfelter, J. [Yale Univ., New Haven, CT (United States); Axani, S. N. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Babu, K [Oklahoma State Univ., Stillwater, OK (United States); Backhouse, C. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Band, H. R. [Yale Univ., New Haven, CT (United States); Barbeau, P. S. [Duke Univ., Durham, NC (United States); Barros, N. [Univ. of Pennsylvania, Philadelphia, PA (United States); Bernstein, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Betancourt, M. [Illinois Inst. of Technology, Chicago, IL (United States); Bishai, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blucher, E. [Univ. of Chicago, IL (United States); Bouffard, J. [State Univ. of New York (SUNY), Albany, NY (United States); Bowden, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brice, S. [Illinois Inst. of Technology, Chicago, IL (United States); Bryan, C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Camilleri, L. [Columbia Univ., New York, NY (United States); Cao, J. [Inst. of High Energy Physics, Beijing (China); Carlson, J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Carr, R. E. [Columbia Univ., New York, NY (United States); Chatterjee, A. [Univ. of Texas, Arlington, TX (United States); Chen, M. [Univ. of California, Irvine, CA (United States); Chen, S. [Tsinghua Univ., Beijing (China); Chiu, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Church, E. D. [Illinois Inst. of Technology, Chicago, IL (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Collar, J. I. [Univ. of Chicago, IL (United States); Collin, G. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Conrad, J. M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Convery, M. R. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Cooper, R. L. [Indiana Univ., Bloomington, IN (United States); Cowen, D. [Pennsylvania State Univ., University Park, PA (United States); Davoudiasl, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gouvea, A. D. [Northwestern Univ., Evanston, IL (United States); Dean, D. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Deichert, G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Descamps, F. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); DeYoung, T. [Michigan State Univ., East Lansing, MI (United States); Diwan, M. V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Djurcic, Z. [Argonne National Lab. (ANL), Argonne, IL (United States); Dolinski, M. J. [Drexel Univ., Philadelphia, PA (United States); Dolph, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Donnelly, B. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Dwyer, D. A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dytman, S. [Univ. of Pittsburgh, PA (United States); Efremenko, Y. [Univ. of Tennessee, Knoxville, TN (United States); Everett, L. L. [Univ. of Wisconsin, Madison, WI (United States); Fava, A. [University of Padua, Padova (Italy); Figueroa-Feliciano, E. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Fleming, B. [Yale Univ., New Haven, CT (United States); Friedland, A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fujikawa, B. K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gaisser, T. K. [Univ. of Delaware, Newark, DE (United States); Galeazzi, M. [Univ. of Miami, FL (United States); Galehouse, DC [Univ. of Akron, OH (United States); Galindo-Uribarri, A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Garvey, G. T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gautam, S. [Tribhuvan Univ., Kirtipur (Nepal); Gilje, K. E. [Illinois Inst. of Technology, Chicago, IL (United States); Gonzalez-Garcia, M. [Stony Brook Univ., NY (United States); Goodman, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Gordon, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gramellini, E. [Yale Univ., New Haven, CT (United States); Green, M. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Guglielmi, A. [University of Padua, Padova (Italy); Hackenburg, R. W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hackenburg, A. [Yale Univ., New Haven, CT (United States); Halzen, F. [Univ. of Wisconsin, Madison, WI (United States); Han, K. [Yale Univ., New Haven, CT (United States); Hans, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Harris, D. [Illinois Inst. of Technology, Chicago, IL (United States); Heeger, K. M. [Yale Univ., New Haven, CT (United States); Herman, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hill, R. [Univ. of Chicago, IL (United States); Holin, A. [Univ. College London, Bloomsbury (United Kingdom); Huber, P. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Jaffe, D. E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Johnson, R. A. [Univ. of Cincinnati, OH (United States); Joshi, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Karagiorgi, G. [Univ. of Manchester (United Kingdom); Kaufman, L. J. [Indiana Univ., Bloomington, IN (United States); Kayser, B. [Illinois Inst. of Technology, Chicago, IL (United States); Kettell, S. H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Kirby, B. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Klein, J. R. [Univ. of Texas, Arlington, TX (United States); Kolomensky, Y. G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Kriske, R. M. [Univ. of Minnesota, Minneapolis, MN (United States); Lane, C. E. [Drexel Univ., Philadelphia, PA (United States); Langford, T. J. [Yale Univ., New Haven, CT (United States); Lankford, A. [Univ. of California, Irvine, CA (United States); Lau, K. [Univ. of Houston, TX (United States); Learned, J. G. [Univ. of Hawaii, Honolulu, HI (United States); Ling, J. [Univ. of Illinois, Urbana-Champaign, IL (United States); Link, J. M. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Lissauer, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Littenberg, L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Littlejohn, B. R. [Illinois Inst. of Technology, Chicago, IL (United States); Lockwitz, S. [Illinois Inst. of Technology, Chicago, IL (United States); Lokajicek, M. [Inst. of Physics of the Academy of Sciences of Czech Republic, Prague (Czech Republic); Louis, W. C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Luk, K. [Univ. of California, Berkeley, CA (United States); Lykken, J. [Illinois Inst. of Technology, Chicago, IL (United States); Marciano, W. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Maricic, J. [Univ. of Hawaii, Honolulu, HI (United States); Markoff, D. M. [North Carolina Central Univ., Durham, NC (United States); Caicedo, D. A. M. [Illinois Inst. of Technology, Chicago, IL (United States); Mauger, C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mavrokoridis, K. [Univ. of Liverpool (United Kingdom); McCluskey, E. [Illinois Inst. of Technology, Chicago, IL (United States); McKeen, D. [Univ. of Washington, Seattle, WA (United States); McKeown, R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Mills, G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mocioiu, I. [Pennsylvania State Univ., University Park, PA (United States); Monreal, B. [Univ. of California, Santa Barbara, CA (United States); Mooney, M. R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Morfin, J. G. [Illinois Inst. of Technology, Chicago, IL (United States); Mumm, P. [National Inst. of Standards and Technology (NIST), Boulder, CO (United States); Napolitano, J. [Temple Univ., Philadelphia, PA (United States); Neilson, R. [Drexel Univ., Philadelphia, PA (United States); Nelson, J. K. [College of William and Mary, Williamsburg, VA (United States); Nessi, M. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Norcini, D. [Yale Univ., New Haven, CT (United States); Nova, F. [Univ. of Texas, Austin, TX (United States); Nygren, D. R. [Univ. of Texas, Arlington, TX (United States); Gann, GDO [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Palamara, O. [Illinois Inst. of Technology, Chicago, IL (United States); Parsa, Z. [Brookhaven National Lab. (BNL), Upton, NY (United States); Patterson, R. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Paul, P. [Stony Brook Univ., NY (United States); Pocar, A. [Univ. of Massachusetts, Amherst, MA (United States); Qian, X. [Brookhaven National Lab. (BNL), Upton, NY (United States); Raaf, J. L. [Illinois Inst. of Technology, Chicago, IL (United States); Rameika, R. [Illinois Inst. of Technology, Chicago, IL (United States); Ranucci, G. [National Inst. of Nuclear Physics, Milano (Italy); Ray, H. [Univ. of Florida, Gainesville, FL (United States); Reyna, D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rich, G. C. [Triangle Universities Nuclear Lab., Durham, NC (United States); Rodrigues, P. [Univ. of Rochester, NY (United States); Romero, E. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Rosero, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Rountree, S. D. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Rybolt, B. [Univ. of Tennessee, Knoxville, TN (United States); Sanchez, M. C. [Iowa State Univ., Ames, IA (United States); Santucci, G. [Stony Brook Univ., NY (United States); Schmitz, D. [Univ. of Chicago, IL (United States); Scholberg, K. [Duke Univ., Durham, NC (United States); Seckel, D. [Univ. of Delaware, Newark, DE (United States); Shaevitz, M. [Columbia Univ., New York, NY (United States); Shrock, R. [Stony Brook Univ., NY (United States); Smy, M. B. [Univ. of California, Irvine, CA (United States); Soderberg, M. [Syracuse Univ., NY (United States); Sonzogni, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sousa, A. B. [Univ. of Cincinnati, OH (United States); Spitz, J. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); John, J. M. S. [Univ. of Cincinnati, OH (United States); Stewart, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Strait, J. B. [Illinois Inst. of Technology, Chicago, IL (United States); Sullivan, G. [Univ. of Maryland, College Park, MD (United States); Svoboda, R. [Univ. of California, Davis, CA (United States); Szelc, A. M. [Yale Univ., New Haven, CT (United States); Tayloe, R. [Indiana Univ., Bloomington, IN (United States); Thomson, M. A. [Univ. of Cambridge (United Kingdom); Toups, M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Vacheret, A. [Univ. of Oxford (United Kingdom); Vagins, M. [Univ. of California, Irvine, CA (United States); Water, R. G. V. D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Vogelaar, R. B. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Weber, M. [Bern (Switzerland); Weng, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wetstein, M. [Univ. of Chicago, IL (United States); White, C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); White, B. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Whitehead, L. [Univ. of Houston, TX (United States); Whittington, D. W. [Indiana Univ., Bloomington, IN (United States); Wilking, M. J. [Stony Brook Univ., NY (United States); Wilson, R. J. [Colorado State Univ., Fort Collins, CO (United States); Wilson, P. [Illinois Inst. of Technology, Chicago, IL (United States); Winklehner, D. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Winn, D. R. [Fairfield Univ., CT (United States); Worcester, E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yang, L. [Univ. of Illinois, Urbana-Champaign, IL (United States); Yeh, M [Brookhaven National Lab. (BNL), Upton, NY (United States); Yokley, Z. W. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Yoo, J. [Illinois Inst. of Technology, Chicago, IL (United States); Yu, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yu, J. [Univ. of Texas, Arlington, TX (United States); Zhang, C. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2017-04-03

The US neutrino community gathered at the Workshop on the Intermediate Neutrino Program (WINP) at Brookhaven National Laboratory February 4-6, 2015 to explore opportunities in neutrino physics over the next five to ten years. Scientists from particle, astroparticle and nuclear physics participated in the workshop. The workshop examined promising opportunities for neutrino physics in the intermediate term, including possible new small to mid-scale experiments, US contributions to large experiments, upgrades to existing experiments, R&D plans and theory. The workshop was organized into two sets of parallel working group sessions, divided by physics topics and technology. Physics working groups covered topics on Sterile Neutrinos, Neutrino Mixing, Neutrino Interactions, Neutrino Properties and Astrophysical Neutrinos. Technology sessions were organized into Theory, Short-Baseline Accelerator Neutrinos, Reactor Neutrinos, Detector R&D and Source, Cyclotron and Meson Decay at Rest sessions.This report summarizes discussion and conclusions from the workshop.

Comments on intermediate-scale models

International Nuclear Information System (INIS)

Ellis, J.; Enqvist, K.; Nanopoulos, D.V.; Olive, K.

1987-01-01

Some superstring-inspired models employ intermediate scales m I of gauge symmetry breaking. Such scales should exceed 10 16 GeV in order to avoid prima facie problems with baryon decay through heavy particles and non-perturbative behaviour of the gauge couplings above m I . However, the intermediate-scale phase transition does not occur until the temperature of the Universe falls below O(m W ), after which an enormous excess of entropy is generated. Moreover, gauge symmetry breaking by renormalization group-improved radiative corrections is inapplicable because the symmetry-breaking field has not renormalizable interactions at scales below m I . We also comment on the danger of baryon and lepton number violation in the effective low-energy theory. (orig.)

Species redistribution during solidification of nuclear fuel waste metal castings

Energy Technology Data Exchange (ETDEWEB)

Naterer, G F; Schneider, G E [Waterloo Univ., ON (Canada)

1994-12-31

An enthalpy-based finite element model and a binary system species redistribution model are developed and applied to problems associated with solidification of nuclear fuel waste metal castings. Minimal casting defects such as inhomogeneous solute segregation and cracks are required to prevent container corrosion and radionuclide release. The control-volume-based model accounts for equilibrium solidification for low cooling rates and negligible solid state diffusion for high cooling rates as well as intermediate conditions. Test problems involving nuclear fuel waste castings are investigated and correct limiting cases of species redistribution are observed. (author). 11 refs., 1 tab., 13 figs.

Surface Intermediate Zone of Submerged Turbulent Buoyant Jet in Current

DEFF Research Database (Denmark)

Chen, H. B.; Larsen, Torben

1995-01-01

This paper deals with the intermediate zone between the jet and plume stages of a submerged buoyant discharge from sea outfall in current. The stability criteria, plume width and height after the intermediate zone and the dilution within the intermediate region have been studied theoretically and...

Digenean trematode species in the cockle Cerastodema edule: identification key and distribution along the north-eastern Atlantic shoreline

DEFF Research Database (Denmark)

Montaudouin, Xavier De; Thieltges, David W.; Gam, Mériame

2009-01-01

host. The remaining eleven species have cockles as their second intermediate host. Water birds and fish are the definitive hosts to twelve and four species, respectively. Cockles are infected with digeneans along the latitudinal gradient from southern Morocco to the western region of the Barents Sea...

Computational uncertainties in silicon dioxide/plutonium intermediate neutron spectrum systems

International Nuclear Information System (INIS)

Jaegers, P.J.

1997-01-01

In the past several years, several proposals have been made for the long-term stabilization and storage of surplus fissile materials. Many of these proposed scenarios involve systems that have an intermediate neutron energy spectrum. Such intermediate-energy systems are dominated by scattering and fission events induced by neutrons ranging in energy from 1 eV to 100keV. To ensure adequate safety margins and cost effectiveness, it is necessary to have benchmark data for these intermediate-energy spectrum systems; however, a review of the nuclear criticality benchmarks indicates that no formal benchmarks are available. Nuclear data uncertainties have been reported for some types of intermediate-energy spectrum systems. Using a variety of Monte Carlo computer codes and cross-section sets, reported significant variations in the calculated k ∞ of intermediate-energy spectrum metal/ 235 U systems. We discuss the characteristics of intermediate neutron spectrum systems and some of the computational differences that can occur in calculating the k eff of these systems

On the stability of rotational discontinuities and intermediate shocks

International Nuclear Information System (INIS)

Lee, L.C.; Huang, L.; Chao, J.K.

1989-01-01

The stability of rotational discontinuities and intermediate shocks is studied based on a hybrid simulation code. The simulation results show that rotational discontinuities are stable and intermediate shocks are not stationary. Intermediate shocks tend to evolve to rotational discontinuities and waves. The authors employ several different initial profiles for the magnetic field in the transition region and find that the final structure of the discontinuities or shocks is not sensitive to the initial magnetic field profile. The present results are different from those obtained from the resistive MHD simulations. Furthermore, their study indicates that the kinetic effect of particles plays an important role in the structure and stability of rotational discontinuities and intermediate shocks

ABA-alcohol is an intermediate in abscisic acid biosynthesis

International Nuclear Information System (INIS)

Rock, C.D.; Zeevaart, J.A.D.

1990-01-01

It has been established that ABA-aldehyde is a precursor to ABA. The ABA-deficient flacca and sitiens mutants of tomato are blocked in the conversion of ABA-aldehyde to ABA, and accumulate trans-ABA-alcohol. 18 O-Labeling studies of ABA in flacca and sitiens show that these mutants synthesize a large percentage of [ 18 O]ABA which contains two 18 O atoms in the carboxyl group. Furthermore, the mutants synthesize much greater amounts of trans-ABA-glucose ester (t-ABA-GE) compared with the wild type, and this [ 18 O]t-ABA-GE is also double labeled in the carboxyl group. Our interpretation of these data is that the 18 O in ABA-aldehyde is trapped in the side chain by reduction to [ 18 O]ABA-alcohol, followed by isomerization to [ 18 O]t-ABA-alcohol and oxidation with 18 O 2 to [ 18 O]t-ABA. The [ 18 O]t-ABA is then rapidly converted to [ 18 O]t-ABA-GE. Because [ 18 O]ABA doubly labeled in the carboxyl group has been observed in small amounts in labeling experiments with several species, and various species have been shown to convert ABA-aldehyde to ABA-alcohol and t-ABA-alcohol, we propose that ABA-alcohol is an ABA intermediate in a shunt pathway

MNE Entrepreneurial Capabilities at Intermediate Levels

DEFF Research Database (Denmark)

Hoenen, Anne K.; Nell, Phillip Christopher; Ambos, Björn

2014-01-01

at intermediate geographical levels differ from local subsidiaries and global corporate headquarters, and why those differences are important. We illustrate our arguments using data on European regional headquarters (RHQs). We find that RHQs' entrepreneurial capabilities depend on their external embeddedness...... and on the heterogeneous information that is generated through dissimilar markets within the region. Our study opens up for an interesting discussion of the independence of these mechanisms. In sum, we contribute to the understanding of the entrepreneurial role of intermediate units in general and RHQs in particular....

Use of tree species by White-throated treerunner (Pygarrhichas albogularis King) in a secondary native forest of southern Chile

OpenAIRE

Gantz, Alberto; Yañez, Miguel; Orellana, José I.; Sade, Soraya; Valdivia, Carlos E.

2015-01-01

ABSTRACT In forest ecosystems, numerous species of insectivorous birds use certain tree species as feeding and nesting substrates. Between 2009 and 2010, the use of different floristic components as feeding substrate by the Pygarrhichas albogularis King, 1831 was evaluated in a southern Chilean secondary native forest. From a total of 13 trees and bush species, six tree species were used by P. albogularis as a feeding substrate. Tree use was limited to intermediate heights (11-20 m) and, main...

Photosynthetic temperature responses of tree species in Rwanda: evidence of pronounced negative effects of high temperature in montane rainforest climax species.

Science.gov (United States)

Vårhammar, Angelica; Wallin, Göran; McLean, Christopher M; Dusenge, Mirindi Eric; Medlyn, Belinda E; Hasper, Thomas B; Nsabimana, Donat; Uddling, Johan

2015-05-01

The sensitivity of photosynthetic metabolism to temperature has been identified as a key uncertainty for projecting the magnitude of the terrestrial feedback on future climate change. While temperature responses of photosynthetic capacities have been comparatively well investigated in temperate species, the responses of tropical tree species remain unexplored. We compared the responses of seedlings of native cold-adapted tropical montane rainforest tree species with those of exotic warm-adapted plantation species, all growing in an intermediate temperature common garden in Rwanda. Leaf gas exchange responses to carbon dioxide (CO2 ) at different temperatures (20-40°C) were used to assess the temperature responses of biochemical photosynthetic capacities. Analyses revealed a lower optimum temperature for photosynthetic electron transport rates than for Rubisco carboxylation rates, along with lower electron transport optima in the native cold-adapted than in the exotic warm-adapted species. The photosynthetic optimum temperatures were generally exceeded by daytime peak leaf temperatures, in particular in the native montane rainforest climax species. This study thus provides evidence of pronounced negative effects of high temperature in tropical trees and indicates high susceptibility of montane rainforest climax species to future global warming. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Financial Intermediation and Economic Growth of Jordan 1964-1988

OpenAIRE

Magableh, Ali H.

1995-01-01

Until recently, the economics and financial literature placed little attention on the role that financial intermediation can play in accelerating the rate of economic development in less Developed Countries (LDCs). This has been changed now, however, where some instrumental role has been emphasised for financial intermediation in the process of economic development and growth. It is argued that an expansion of the financial system, size and intermediation in LDCs tends to increase the level o...

Perennial pastures for marginal farming country in southern Queensland. 2. Potential new grass cultivar evaluation

Directory of Open Access Journals (Sweden)

Richard G. Silcock

2015-01-01

Full Text Available Trials in the Condamine-Balonne basin, Australia, compared 11 promising perennial pasture grass accessions (4 Bothriochloa, 2 Cenchrus, 2 Urochloa and 1 each of Digitaria, Eragrostis and Panicum species against the best similar commercial cultivars on the basis of ease of establishment from seed, persistence once established, forage yield and ease of seed production.  Accessions sown at a site were determined by prior experience with them on a range of soils.  High quality seed was relatively easy to produce for both Urochloa species and for Eragrostis curvula CPI 30374 but problematic for the Bothriochloa spp.  Once established, all accessions persisted for 3–5 years and most were well grazed, but adequate establishment was sometimes a problem with Panicum stapfianum and Bothriochloa ewartiana.  The dry matter yield ratings of the non-commercial lines were similar to those of the commercial equivalents of the same species.  While agronomically valuable, none of the promising new grasses was considered worthy of commercialization at this point because their strengths did not warrant the setting up of a seed-production business in competition with current commercial enterprises.  Long-standing cultivars such as Gayndah buffel and Nixon sabi grass continued to exhibit their superior pasture qualities.Keywords: Herbicide tolerance, persistence, forage yield, establishment ease, commercialization, seed production.DOI: 10.17138/TGFT(315-26

Genetic diversity and genomic resources available for the small millet crops to accelerate a New Green Revolution.

Science.gov (United States)

Goron, Travis L; Raizada, Manish N

2015-01-01

Small millets are nutrient-rich food sources traditionally grown and consumed by subsistence farmers in Asia and Africa. They include finger millet (Eleusine coracana), foxtail millet (Setaria italica), kodo millet (Paspalum scrobiculatum), proso millet (Panicum miliaceum), barnyard millet (Echinochloa spp.), and little millet (Panicum sumatrense). Local farmers value the small millets for their nutritional and health benefits, tolerance to extreme stress including drought, and ability to grow under low nutrient input conditions, ideal in an era of climate change and steadily depleting natural resources. Little scientific attention has been paid to these crops, hence they have been termed "orphan cereals." Despite this challenge, an advantageous quality of the small millets is that they continue to be grown in remote regions of the world which has preserved their biodiversity, providing breeders with unique alleles for crop improvement. The purpose of this review, first, is to highlight the diverse traits of each small millet species that are valued by farmers and consumers which hold potential for selection, improvement or mechanistic study. For each species, the germplasm, genetic and genomic resources available will then be described as potential tools to exploit this biodiversity. The review will conclude with noting current trends and gaps in the literature and make recommendations on how to better preserve and utilize diversity within these species to accelerate a New Green Revolution for subsistence farmers in Asia and Africa.

Phytotoxicity Study on Bidens sulphurea Sch. Bip. as a Preliminary Approach for Weed Control.

Science.gov (United States)

da Silva, Bruna P; Nepomuceno, Mariluce P; Varela, Rosa M; Torres, Ascensión; Molinillo, José M G; Alves, Pedro L C A; Macías, Francisco A

2017-06-28

Farmers of the Franca region in Brazil observed that Bidens sulphurea was able to eliminate the Panicum maximum weed, which infected coffee plantations, without affecting the crop. In an effort to determine if the inhibitory effects observed were due to the presence of phytotoxic compounds from leaves and roots, a biodirected isolation and spectroscopic characterization has been carried out. The leaf dichloromethane and root acetone extracts were the most active, and the former appeared to be more phytotoxic to the target species, including four weeds. A total of 26 compounds were isolated from leaves and roots, and four of them are described here for the first time. The major compounds in the leaf extract are the sesquiterpene lactones costunolide, reynosin, and santamarine, and these showed marked inhibition. Amaranthus viridis and Panicum maximum were the most sensitive species of the weeds tested. These three phytotoxic lactones were also evaluated on A. viridis and P. maximum under hydroponic conditions. A. viridis was the most affected species with the three lactones, and santamarine was the most phytotoxic compound on both. This is the first time that the phytotoxicity of sesquiterpene lactones has been evaluated on hydroponic culture. The work described here is a preliminary approach for the use of B. sulphurea for weed control in agriculture, both as a cover crop and by use of its components as natural herbicide leads.

Perspective: Spectroscopy and kinetics of small gaseous Criegee intermediates

International Nuclear Information System (INIS)

Lee, Yuan-Pern

2015-01-01

The Criegee intermediates, carbonyl oxides proposed by Criegee in 1949 as key intermediates in the ozonolysis of alkenes, play important roles in many aspects of atmospheric chemistry. Because direct detection of these gaseous intermediates was unavailable until recently, previous understanding of their reactions, derived from indirect experimental evidence, had great uncertainties. Recent laboratory detection of the simplest Criegee intermediate CH 2 OO and some larger members, produced from ultraviolet irradiation of corresponding diiodoalkanes in O 2 , with various methods such as photoionization, ultraviolet absorption, infrared absorption, and microwave spectroscopy opens a new door to improved understanding of the roles of these Criegee intermediates. Their structures and spectral parameters have been characterized; their significant zwitterionic nature is hence confirmed. CH 2 OO, along with other products, has also been detected directly with microwave spectroscopy in gaseous ozonolysis reactions of ethene. The detailed kinetics of the source reaction, CH 2 I + O 2 , which is critical to laboratory studies of CH 2 OO, are now understood satisfactorily. The kinetic investigations using direct detection identified some important atmospheric reactions, including reactions with NO 2 , SO 2 , water dimer, carboxylic acids, and carbonyl compounds. Efforts toward the characterization of larger Criegee intermediates and the investigation of related reactions are in progress. Some reactions of CH 3 CHOO are found to depend on conformation. This perspective examines progress toward the direct spectral characterization of Criegee intermediates and investigations of the associated reaction kinetics, and indicates some unresolved problems and prospective challenges for this exciting field of research

Characterization of Sarcocystis from four species of hawks from Georgia, USA.

Science.gov (United States)

Yabsley, Michael J; Ellis, Angela E; Stallknecht, David E; Howerth, Elizabeth W

2009-02-01

During 2001 to 2004, 4 species of hawks (Buteo and Accipiter spp.) from Georgia were surveyed for Sarcocystis spp. infections by examining intestinal sections. In total, 159 of 238 (66.8%) hawks examined were infected with Sarcocystis spp. Samples from 10 birds were characterized by sequence analysis of a portion of the 18S rRNA gene (783 base pairs). Only 3 of the 10 sequences from the hawks were identical; the remainder differed by at least 1 nucleotide. Phylogenetic analysis failed to resolve the position of the hawk Sarcocystis species, but they were closely related several Sarcocystis species from raptors, rodents, and Sarcocystis neurona. The high genetic diversity of Sarcocystis suggests that more than 1 species infects these 4 hawk species; however, additional molecular or experimental work will be required to determine the speciation and diversity of parasites infecting these avian hosts. In addition to assisting with determining species richness of Sarcocystis in raptors, molecular analysis should be useful in the identification of potential intermediate hosts.

Biodiversity and the Lotka-Volterra theory of species interactions: open systems and the distribution of logarithmic densities.

Science.gov (United States)

Wilson, William G; Lundberg, Per

2004-09-22

Theoretical interest in the distributions of species abundances observed in ecological communities has focused recently on the results of models that assume all species are identical in their interactions with one another, and rely upon immigration and speciation to promote coexistence. Here we examine a one-trophic level system with generalized species interactions, including species-specific intraspecific and interspecific interaction strengths, and density-independent immigration from a regional species pool. Comparisons between results from numerical integrations and an approximate analytic calculation for random communities demonstrate good agreement, and both approaches yield abundance distributions of nearly arbitrary shape, including bimodality for intermediate immigration rates.

Intermediate-Mass Black Holes

Science.gov (United States)

Miller, M. Coleman; Colbert, E. J. M.

2004-01-01

The mathematical simplicity of black holes, combined with their links to some of the most energetic events in the universe, means that black holes are key objects for fundamental physics and astrophysics. Until recently, it was generally believed that black holes in nature appear in two broad mass ranges: stellar-mass (M~3 20 M⊙), which are produced by the core collapse of massive stars, and supermassive (M~106 1010 M⊙), which are found in the centers of galaxies and are produced by a still uncertain combination of processes. In the last few years, however, evidence has accumulated for an intermediate-mass class of black holes, with M~102 104 M⊙. If such objects exist they have important implications for the dynamics of stellar clusters, the formation of supermassive black holes, and the production and detection of gravitational waves. We review the evidence for intermediate-mass black holes and discuss future observational and theoretical work that will help clarify numerous outstanding questions about these objects.

Intermediate Levels of Visual Processing

National Research Council Canada - National Science Library

Nakayama, Ken

1998-01-01

...) surface representation, here we have shown that there is an intermediate level of visual processing, between the analysis of the image and higher order representations related to specific objects; (2...

Intermediate energy proton and light-ion scattering

International Nuclear Information System (INIS)

Moss, J.M.

1981-01-01

A review is presented of recent (1979-81) developments in the field of intermediate-energy proton and light-ion scattering from nuclei. New theoretical and calculational techniques of particular interest to experimentalists are discussed. Emphasis is placed on topics in nuclear structure physics - giant resonances, pion-condensation precursor phenomena, and polarization transfer (spin-flip) experiments - where intermediate energy proton and light-ion scattering has made new and unique contributions

Comments on intermediate-scale models

Energy Technology Data Exchange (ETDEWEB)

Ellis, J.; Enqvist, K.; Nanopoulos, D.V.; Olive, K.

1987-04-23

Some superstring-inspired models employ intermediate scales m/sub I/ of gauge symmetry breaking. Such scales should exceed 10/sup 16/ GeV in order to avoid prima facie problems with baryon decay through heavy particles and non-perturbative behaviour of the gauge couplings above m/sub I/. However, the intermediate-scale phase transition does not occur until the temperature of the Universe falls below O(m/sub W/), after which an enormous excess of entropy is generated. Moreover, gauge symmetry breaking by renormalization group-improved radiative corrections is inapplicable because the symmetry-breaking field has not renormalizable interactions at scales below m/sub I/. We also comment on the danger of baryon and lepton number violation in the effective low-energy theory.

Proceedings of the Workshop on Program Options in Intermediate-Energy Physics. Keynote address: New directions in intermediate-energy nuclear physics

International Nuclear Information System (INIS)

Brown, G.E.

1980-05-01

This report presents the keynote address given by G.E. Brown at a LASL colloquium on August 21, 1979, for the Workshop on Program Options in Intermediate-Energy Physics. Professor Brown reviewed major topics of interest in intermediate-energy nuclear physics and suggested experimental approaches that might be most productive in the near future. 22 figures

Projecting non-diffracting waves with intermediate-plane holography.

Science.gov (United States)

Mondal, Argha; Yevick, Aaron; Blackburn, Lauren C; Kanellakopoulos, Nikitas; Grier, David G

2018-02-19

We introduce intermediate-plane holography, which substantially improves the ability of holographic trapping systems to project propagation-invariant modes of light using phase-only diffractive optical elements. Translating the mode-forming hologram to an intermediate plane in the optical train can reduce the need to encode amplitude variations in the field, and therefore complements well-established techniques for encoding complex-valued transfer functions into phase-only holograms. Compared to standard holographic trapping implementations, intermediate-plane holograms greatly improve diffraction efficiency and mode purity of propagation-invariant modes, and so increase their useful non-diffracting range. We demonstrate this technique through experimental realizations of accelerating modes and long-range tractor beams.

Alien species of fish parasites in the coastal lakes and lagoons of the southern Baltic

Directory of Open Access Journals (Sweden)

Jolanta Morozińska-Gogol

2009-03-01

Full Text Available Alien species are now found all over the world. New fish parasites have been unintentionally introduced with infected alien fish imported for aquaculture or have sometimes spread with their intermediate invertebrate hosts transported in the ballast waters of ships. Four alien fish parasites have been recorded in Polish coastal lakes and lagoons, all parasitising eels. Three were introduced with the final host - the Japanese eel - introduced for aquaculture (Anguillicola crassus, Pseudodactylogyrus anguillae and Pseudodactylogyrus bini and one (Paratenuisentis ambiguus with its sole intermediate host (Gammarus tigrinus.

Processing and validation of intermediate energy evaluated data files

International Nuclear Information System (INIS)

2000-01-01

Current accelerator-driven and other intermediate energy technologies require accurate nuclear data to model the performance of the target/blanket assembly, neutron production, activation, heating and damage. In a previous WPEC subgroup, SG13 on intermediate energy nuclear data, various aspects of intermediate energy data, such as nuclear data needs, experiments, model calculations and file formatting issues were investigated and categorized to come to a joint evaluation effort. The successor of SG13, SG14 on the processing and validation of intermediate energy evaluated data files, goes one step further. The nuclear data files that have been created with the aforementioned information need to be processed and validated in order to be applicable in realistic intermediate energy simulations. We emphasize that the work of SG14 excludes the 0-20 MeV data part of the neutron evaluations, which is supposed to be covered elsewhere. This final report contains the following sections: section 2: a survey of the data files above 20 MeV that have been considered for validation in SG14; section 3: a summary of the review of the 150 MeV intermediate energy data files for ENDF/B-VI and, more briefly, the other libraries; section 4: validation of the data library against an integral experiment with MCNPX; section 5: conclusions. (author)

Interspecific differences in growth response and tolerance to the antibiotic sulfadiazine in ten clonal wetland plants in South China.

Science.gov (United States)

Chen, Jinfeng; Xu, Huilian; Sun, Yingbo; Huang, Lili; Zhang, Peixia; Zou, Chunping; Yu, Bo; Zhu, Genfa; Zhao, Chaoyi

2016-02-01

Pollution caused by residual antibiotics is a worldwide environmental issue. Antibiotic residues often occur in aquatic ecosystems, posing threats to the health of aquatic organisms. The effects of antibiotic residues on the growth of crop plants and on human health are reasonably well known. However, less is known about antibiotic effects on wetland plants. Therefore, we studied the response and tolerance of ten clonal wetland plants grown in soil spiked with sulfadiazine at 10 mg kg(-1) (an environmentally relevant concentration) and 100 mg kg(-1). At 10 mg kg(-1), ramet number was the least affected trait, while root number was the most affected among plant species. Plant shoot and total biomass were reduced in all species except in Cyperus malaccensis var. brevifolius and Panicum repens. Chlorophyll content was reduced in Alocasia macrorrhiza, Saururus chinensis, and Commelina diffusa. In general, Panicum paludosum and C. malaccensis var. brevifolius showed the least reduction of growth parameters, whereas growth of both A. macrorrhiza and S. chinensis was severely reduced. At 100 mg kg(-1), negative responses occurred in all species. Comprehensive tolerance analysis revealed that P. paludosum and C. malaccensis var. brevifolius were the species most resistant to sulfadiazine. These species are potential candidates for sulfadiazine polluted wetland restoration. A. macrorrhiza and S. chinensis were the most susceptible species and they should be protected from sulfadiazine pollution. Relative plant shoot biomass and height were the most useful indicators for evaluating plant tolerance to sulfadiazine. Plant tolerance to sulfadiazine was associated with the differences of plants in height and shoot biomass. Copyright © 2015 Elsevier B.V. All rights reserved.

Is Galba schirazensis (Mollusca, Gastropoda) an intermediate host of Fasciola hepatica (Trematoda, Digenea) in Ecuador?

Science.gov (United States)

Caron, Yannick; Celi-Erazo, Maritza; Hurtrez-Boussès, Sylvie; Lounnas, Mannon; Pointier, Jean-Pierre; Saegerman, Claude; Losson, Bertrand; Benítez-Ortíz, Washington

2017-01-01

Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts is relatively scarce in Ecuador. For three months, lymnaeid snails were sampled (n = 1482) in Pichincha Province at two sites located in a highly endemic area. Snails were identified (based on morphology and ITS-2 sequences) and the infection status was established through microscopic dissection and a multiplex polymerase chain reaction (PCR)-based technique. Techniques based on morphology were not useful to accurately name the collected snail species. Comparison with available DNA sequences showed that a single snail species was collected, Galba schirazensis. Live rediae were observed in 1.75% (26/1482) and Fasciola sp. DNA was detected in 6% (89/1482) of collected snails. The COX-1 region permitted identification of the parasite as Fasciola hepatica. The relative sensitivity and specificity of the microscope study, compared to PCR results, were 25.84% and 99.78%, respectively. The mean size of the snails recorded positive for F. hepatica through crushing and microscopy was significantly higher than the mean size of negative snails, but there was no such difference in PCR-positive snails. The role of G. schirazensis as an intermediate host of F. hepatica in Ecuador is discussed and the hypothesis of an adaptation of the parasite to this invasive snail is proposed. For the first time, an epidemiological survey based on molecular biology-based techniques assessed the possible role of lymnaeid snails in the epidemiology of fasciolosis in Ecuador. © Y. Caron et al., published by EDP Sciences, 2017.

Is Galba schirazensis (Mollusca, Gastropoda an intermediate host of Fasciola hepatica (Trematoda, Digenea in Ecuador?

Directory of Open Access Journals (Sweden)

Caron Yannick

2017-01-01

Full Text Available Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts is relatively scarce in Ecuador. For three months, lymnaeid snails were sampled (n = 1482 in Pichincha Province at two sites located in a highly endemic area. Snails were identified (based on morphology and ITS-2 sequences and the infection status was established through microscopic dissection and a multiplex polymerase chain reaction (PCR-based technique. Techniques based on morphology were not useful to accurately name the collected snail species. Comparison with available DNA sequences showed that a single snail species was collected, Galba schirazensis. Live rediae were observed in 1.75% (26/1482 and Fasciola sp. DNA was detected in 6% (89/1482 of collected snails. The COX-1 region permitted identification of the parasite as Fasciola hepatica. The relative sensitivity and specificity of the microscope study, compared to PCR results, were 25.84% and 99.78%, respectively. The mean size of the snails recorded positive for F. hepatica through crushing and microscopy was significantly higher than the mean size of negative snails, but there was no such difference in PCR-positive snails. The role of G. schirazensis as an intermediate host of F. hepatica in Ecuador is discussed and the hypothesis of an adaptation of the parasite to this invasive snail is proposed. For the first time, an epidemiological survey based on molecular biology-based techniques assessed the possible role of lymnaeid snails in the epidemiology of fasciolosis in Ecuador.

Two-Step Amyloid Aggregation: Sequential Lag Phase Intermediates

Science.gov (United States)

Castello, Fabio; Paredes, Jose M.; Ruedas-Rama, Maria J.; Martin, Miguel; Roldan, Mar; Casares, Salvador; Orte, Angel

2017-01-01

The self-assembly of proteins into fibrillar structures called amyloid fibrils underlies the onset and symptoms of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s. However, the molecular basis and mechanism of amyloid aggregation are not completely understood. For many amyloidogenic proteins, certain oligomeric intermediates that form in the early aggregation phase appear to be the principal cause of cellular toxicity. Recent computational studies have suggested the importance of nonspecific interactions for the initiation of the oligomerization process prior to the structural conversion steps and template seeding, particularly at low protein concentrations. Here, using advanced single-molecule fluorescence spectroscopy and imaging of a model SH3 domain, we obtained direct evidence that nonspecific aggregates are required in a two-step nucleation mechanism of amyloid aggregation. We identified three different oligomeric types according to their sizes and compactness and performed a full mechanistic study that revealed a mandatory rate-limiting conformational conversion step. We also identified the most cytotoxic species, which may be possible targets for inhibiting and preventing amyloid aggregation.

Composição florística das plantas daninhas na cultura de guaraná (Paullinia cupana, no estado do Amazonas Floristic composition of weeds in guarana (Paullinia cupana crop in Amazonas, Brazil

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S.M.F. Albertino

2004-09-01

Full Text Available O estudo da composição da flora de plantas daninhas de uma área ou de uma região agrícola é importante, por identificar a diversidade de espécies e contribuir para recomendação de estratégias de manejo a serem empregadas nos sistemas agrícolas. Este trabalho teve o objetivo de identificar a composição florística de plantas daninhas em plantios de guaraná em cinco municípios (Coari, Iranduba, Maués, Presidente Figueiredo e Urucará do Estado do Amazonas. As plantas daninhas foram amostradas em áreas de produtores desses municípios e identificadas por classe, família e espécie. Foram coletados 14.707 indivíduos, distribuídos em 40 famílias e 87 espécies, das quais 70 eram Dicotiledôneas, 13 Monocotiledôneas e quatro Pteridófitas. As Dicotiledôneas apresentaram maior número de família e as Monocotiledôneas de indivíduos. As Pteridófitas ocorreram de forma inexpressiva em todos os municípios. As famílias Poaceae e Asteraceae apresentaram maior número de espécies. Panicum pilosum foi a espécie com maior número de indivíduos, freqüência, densidade e índice de valor de importância. Panicum laxum sobressaiu em Urucará e Iranduba; Scleria malaleuca, em Coari; e Chamaesyce hirta, em Maués. Homolepis aturensis, Paspalum conjugatum e Spermacoce capitata ocorreram nos cinco municípios. Em Maués foi encontrada a maior diversidade de espécies, e em Coari, o maior número de indivíduos. O maior índice de similaridade foi entre Iranduba e Presidente Figueiredo (45%, e o menor, entre Iranduba e Coari (21,43%.The study of the floristic composition of weeds of an area or agricultural region is important since it identifies the diversity of species and provides management strategies to be used under various agricultural system conditions. The objective of this work was to identify the floristic composition of weeds occurring in guaraná crops in five counties (Coari, Iranduba, Maués, Presidente Figueiredo and

Avaliação de três cultivares de Panicum maximum Jacq. sob pastejo: composição da dieta, consumo de matéria seca e ganho de peso animal Evaluation of three varieties of Panicum maximum Jacq. under grazing: diet composition, dry matter intake and animal weight gain

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Patrícia Amarante Brâncio

2003-10-01

Full Text Available Três cultivares de Panicum maximum Jacq. submetidos a pastejo rotativo foram avaliados ao longo do ano, antes e após o período de pastejo, quanto à composição botânica e química da dieta, consumo de matéria seca e ganho de peso animal. Os tratamentos constituíram em: 1 cv. Tanzânia + 50 kg/ha de N, 2 cv. Tanzânia + 100 kg/ha de N, 3 cv. Mombaça + 50 kg/ha de N, e 4 cv. Massai + 50 kg/ha de N. As dietas selecionadas pelos animais na cv. Massai tenderam a apresentar os menores valores de digestibilidade e proteína bruta e os maiores de fibra em detergente neutro, enquanto na cv. Mombaça as dietas continham, em geral, maiores teores de sílica. Os animais selecionaram, em média, 92,4% de folhas verdes, independentemente do tratamento e da época de amostragem. Os animais consumiram semelhantes quantidades de forragem nos diversos tratamentos, apresentando, em média, consumos de 1,9; 2,8; 3,4; e 2,3 kgMS/100kgPV, respectivamente, em junho, setembro e novembro de 1998 e março de 1999. Os piores resultados quanto ao ganho de peso por animal foram verificados na cv. Massai, mas, devido a sua alta capacidade de suporte na época chuvosa, superou a cv. Mombaça e cv. Tanzânia + 50 kg/ha de N, em termos de ganho de peso por área. A participação de folhas, a altura do pasto, o teor de proteína bruta da dieta selecionada pelos animais e o tamanho de bocado foram os fatores que mais influenciaram positivamente o ganho de peso animal.Three varieties of Panicum maximum Jacq. were evaluated by measuring the botanical and chemical composition of the diet, and the dry matter intake and weight gain of the animal under rotational grazing, before and after a period of grazing. The treatments were: 1 v. Tanzânia + 50 kg N/ha, 2 v. Tanzânia + 100 kg N/ha, 3 v. Mombaça + 50 kg N/ha, and 4 v. Massai + 50 kg N/ha. Of the diets selected by the animals, v. Massai tended to show lower values for digestibility and crude protein, and higher values

An improved intermediate resonance method for heterogeneous media

International Nuclear Information System (INIS)

Chiovato, O.; Corno, S.; Pasquantonio, F.Di.

1977-01-01

A new formulation is described of the Intermediate Resonance method which incorporates the previous developments suitably modified and improved, together with some new contributions. The 'intermediate' character is directly introduced in the integral operator K, allowing a more rigorous deduction of the equations for evaluating the intermediate parameters related to the nuclides involved in the system. There is no limit to the number of internal (admixed in the fuel) and external moderators. The capability to take into account the interference scattering has been extended to heterogeneous systems. The Doppler broadening is described by means of new accurate rational approximations to the broadened line shape psi. Finally the use of energy mean values suitably defined refines the values of the resonance integrals and resonance absorption cross sections. The Intermediate Resonance method so extended and improved, has been coded in a group of FORTRAN routines, which have been inserted as a calculation option in the fast section of the GGC code for the evaluation of multigroup cross sections. A series of calculations has been carried out, using these routines, and comparisons have been made with Monte Carlo and Nordheim's methods. The results obtained show that the Intermediate Resonance method developed in the present work offers considerable advantages over Nordheim's method: better accuracy in evaluating resonance absorption cross sections, and much smaller computing times. (author)

Molecular confirmation of trematodes in the snail intermediate hosts from Ratchaburi Province, Thailand

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Sothorn Anucherngchai

2017-05-01

Full Text Available Objective: To analyze the prevalence of trematode infections in the snails intermediate host Tarebia granifera and Melanoides tuberculata collected from Ratchaburi Province by a molecular approach in order to construct a dendrogram to identify species at the cercarial stage. Methods: Specimens were collected from nine districts located in Ratchaburi Province using the stratified sampling method. The samples were examined for cercarial infection using the crushing method. All specimens were amplified by region of internal transcribed spacer 2 (ITS2 based on the PCR technique, and the sequence data were aligned in order to construct the dendrogram by maximum likelihood with 10 000 bootstrap replicates. Results: Five cercarial types were observed comprising parapleurolophocercous cercaria, xiphidiocercaria, megarulous cercaria, furcocercous cercaria and transversotrema cercaria. The overall prevalence of cercarial infection was found to be 7.92% (63 / 795. The parapleurolophocercous cercaria was found in the highest level of prevalence followed by xiphidiocercaria, megarulous cercaria, furcocercous cercaria and transversotrema cercaria, respectively. The parapleurolophocercous cercaria samples were identified and separated into Haplorchis taichui and Haplorchis pumilio, while xiphidiocercaria were identified as Lecithodendriidae and megarulous cercaria were identified as Philophthalmus. The dendrogram separated the cercariae into five groups, which were comprised of parapleurolophocercous cercaria, xiphidiocercaria, megarulous cercaria, furcocercous cercaria and transversotrema cercaria using the sequence of Angiostrongylus cantonensis as an out-group. Conclusions: This is the first study to report on the prevalence of cercarial infection in Ratchaburi Province, Thailand. The high prevalence of cercariae was revealed by the infection in Tarebia granifera and Melanoides tuberculata. Thus, the sequence data of ITS2 can be used to investigate the

A new species of Astragalus (Fabaceae from west coast of Baikal Lake (Irkutsk Oblast

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N. V. Stepantsova

2015-05-01

Full Text Available A new species, Astragalus rytyensis Stepantsova (Fabaceae, growing on the west coast of the lake Baikal, is described. Morphological differences from related taxa – A. versicolor Pall., A. austrosibiricus Schischk., and A. inopinatus Boriss., are discussed and uncertain position of the new species in the system of the genus is emphasized which is intermediate between subg. Phaca (L. Bunge sect. Hemiphaca Bunge and subg. Cercidothrix Bunge sect. Onobrychium Bunge. Ecological and phonological features of A. rytyensis are reported and chromosome numbers of the new (2n = 6x = 48 and related species are counted.

Molecular species analysis of phosphatidylinositol (PI), phosphatidic acid (PA) and diacylglycerol (DG) in rat mast cells

International Nuclear Information System (INIS)

Kennerly, D.A.

1987-01-01

The metabolism of DG, PA and PI were studied in purified rat mast cells to determine whether generally accepted pathways of PI metabolism could explain the pattern of fatty acids seen in these intermediates. A method was developed to separate and quantitate by mass (for DG) or endogenous labeling (for PA and PI) the different molecular species of each lipid that are defined by their component fatty acids. The resultant molecular species fingerprint for each lipid was examined to see if it was similar to other intermediates in the PI cycle. For each class of compounds the percent in a given subclass was recorded. Stimulation caused a reduction of more saturated subclasses and/or an increase in AA containing compounds in PA, PI and DG. The relative similarity of subclasses of 32 P-PA and 32 P-PI supports the view that they are metabolically related. The relative absence of AA-containing species of DG suggests that most of the stimulated increase of DG was not produced by PI hydrolysis

Susceptibility of Staphylococcus species and subspecies to teicoplanin.

Science.gov (United States)

Bannerman, T L; Wadiak, D L; Kloos, W E

1991-01-01

Twenty-four Staphylococcus species and their subspecies were examined for their susceptibilities to teicoplanin by disk diffusion (30-micrograms disk) and agar dilution for the determination of MICs. Moderately susceptible and resistant clinical strains were further tested for their susceptibilities to oxacillin and vancomycin. Teicoplanin resistance was not observed in the reference strains of the various Staphylococcus species isolated from healthy volunteers or animals. However, the novobiocin-resistant species Staphylococcus saprophyticus, Staphylococcus cohnii, Staphylococcus xylosus, Staphylococcus arlettae, Staphylococcus kloosii, and Staphylococcus gallinarum were less susceptible to teicoplanin (MIC, 2 to 8 micrograms/ml) than most of the novobiocin-susceptible species were (MIC, 0.5 to 4 micrograms/ml). Clinical isolates of coagulase-negative species were generally less susceptible to teicoplanin than were reference strains. Seven percent of the Staphylococcus epidermidis clinical strains were moderately susceptible (MIC, 16 micrograms/ml) to teicoplanin. Of these strains, 70% were oxacillin resistant. For Staphylococcus haemolyticus strains, 11% were resistant (MIC, greater than 16 micrograms/ml) and 21% were moderately susceptible to teicoplanin. Of these strains, 95% were oxacillin resistant, No strains of S. epidermidis or S. haemolyticus were intermediate or resistant to vancomycin. Teicoplanin appears to be less active in vitro against oxacillin-resistant S. haemolyticus. However, teicoplanin is an effective antimicrobial agent against many Staphylococcus species. PMID:1835340

Nitric oxide formation from the reaction of nitrite with carp and rabbit hemoglobin at intermediate oxygen saturations

DEFF Research Database (Denmark)

Jensen, Frank Bo

2008-01-01

The nitrite reductase activity of deoxyhemoglobin has received much recent interest because the nitric oxide produced in this reaction may participate in blood flow regulation during hypoxia. The present study used spectral deconvolution to characterize the reaction of nitrite with carp and rabbit...... hemoglobin at different constant oxygen tensions that generate the full range of physiological relevant oxygen saturations. Carp is a hypoxia-tolerant species with very high hemoglobin oxygen affinity, and the high R-state character and low redox potential of the hemoglobin is hypothesized to promote...... NO generation from nitrite. The reaction of nitrite with deoxyhemoglobin leads to a 1 : 1 formation of nitrosylhemoglobin and methemoglobin in both species. At intermediate oxygen saturations, the reaction with deoxyhemoglobin is clearly favored over that with oxyhemoglobin, and the oxyhemoglobin reaction...

Surface-Bound Intermediates in Low-Temperature Methanol Synthesis on Copper. Participants and Spectators

Energy Technology Data Exchange (ETDEWEB)

Yang, Yong; Mei, Donghai; Peden, Charles HF; Campbell, Charles T.; Mims, Charles A.

2015-11-03

The reactivity of surface adsorbed species present on copper catalysts during methanol synthesis at low temperatures was studied by simultaneous infrared spectroscopy (IR) and mass spectroscopy (MS) measurements during “titration” (transient surface reaction) experiments with isotopic tracing. The results show that adsorbed formate is a major bystander species present on the surface under steady-state methanol synthesis reaction conditions, but it cannot be converted to methanol by reaction with pure H₂, nor with H₂ plus added water. Formate-containing surface adlayers for these experiments were produced during steady state catalysis in (a) H₂:CO₂ (with substantial formate coverage) and (b) moist H₂:CO (with no IR visible formate species). Both these reaction conditions produce methanol at steady state with relatively high rates. Adlayers containing formate were also produced by (c) formic acid adsorption. Various "titration" gases were used to probe these adlayers at modest temperatures (T = 410-450K) and 6 bar total pressure. Methanol gas (up to ~1% monolayer equivalent) was produced in "titration" from the H₂:CO₂ catalytic adlayers by H₂ plus water, but not by dry hydrogen. The decay in the formate IR features accelerated in the presence of added water vapor. The H₂:CO:H₂O catalytic adlayer produced similar methanol titration yields in H₂ plus water but showed no surface formate features in IR (less than 0.2% monolayer coverage). Finally, formate from formic acid chemisorption produced no methanol under any titration conditions. Even under (H₂:CO₂) catalytic reaction conditions, isotope tracing showed that pre-adsorbed formate from formic acid did not contribute to the methanol produced. Although non-formate intermediates exist during low temperature methanol synthesis on copper which can be converted to methanol gas

Production of nuclei far from the beta stability line using intermediate-energy heavy ions

International Nuclear Information System (INIS)

Guerreau, D.

1986-05-01

The production of far unstable nuclei using heavy ion accelerators in the intermediate energy domain is reviewed. The various mechanisms responsible for the production of exotic species, mainly the projectile fragmentation and transfer reactions, are discussed, and the first experimental results presented. Results can be summarized as follows: existence of 4 new isotopes 22 C, 23 N, 29 Ne, 30 Ne; indication of bound character of 71 Ni, 72 Ni; clear evidence for bound character of 23 Si, 27 S, 31 Ar, 35 Ca; indications of bound character of 43 V, 46 Mn, 47 Mn, 48 Fe, 50 Co, 52 Co, 52 Ni, 55 Cu, 56 Cu

The management of intermediate level wastes in Sweden

International Nuclear Information System (INIS)

Hultgren, Aa.; Thegerstroem, C.

1980-01-01

A brief overview of current practices and research in Sweden on the management of intermediate level wastes is given. Intermediate level wastes include spent resins, filters and core components from the six power reactors in operation; radioactive wastes from nuclear fuel development at Studsvik and from non-nuclear applications are a minor contribution. (Auth.)

Phytoextraction of contaminated urban soils by Panicum virgatum L. enhanced with application of a plant growth regulator (BAP) and citric acid.

Science.gov (United States)

Aderholt, Matthew; Vogelien, Dale L; Koether, Marina; Greipsson, Sigurdur

2017-05-01

Lead (Pb) contamination in soil represents a threat to human health. Phytoextraction has gained attention as a potential alternative to traditional remediation methods because of lower cost and minimal soil disruption. The North American native switchgrass (Panicum virgatum L.) was targeted due to its ability to produce high biomass and grow across a variety of ecozones. In this study switchgrass was chemically enhanced with applications of the soil-fungicide benomyl, chelates (EDTA and citric acid), and PGR to optimize phytoextraction of Pb and zinc (Zn) from contaminated urban soils in Atlanta, GA. Exogenous application of two plant hormones was compared in multiple concentrations to determine effects on switchgrass growth: indole-3-acetic acid (IAA), and Gibberellic Acid (GA 3 ), and one PGR benzylaminopurine (BAP), The PGR BAP (1.0 μM) was found to generate a 48% increase in biomass compared to Control plants. Chemical application of citric acid, EDTA, benomyl, and BAP were tested separately and in combination in a pot experiment in an environmentally controlled greenhouse to determine the efficacy of phtyoextraction by switchgrass. Soil acidification by citric acid application resulted in highest level of aluminum (Al) and iron (Fe) in plants foliage resulting in severe phytotoxic effects. Total Pb phytoextraction was significantly highest in plants treated with combined chemical application of B + C and B + C + H. Suppression of AMF activities by benomyl application significantly increased concentrations of Al and Fe in roots. Application of benomyl reduced AMF colonization but was also shown to dramatically increase levels of septa fungi infection as compared to Control plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of two organic fertilizers along with Zn and B elements on concentration, uptake of nutrients and some growth parameters in millet (Panicum miliaceum L.

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T Nezhad hoseini

2016-05-01

Full Text Available A field experiment was conducted to study the effect of two organic fertilizers along with zinc and boron elements on some growth parameters, concentration and uptake of nutrients in millet (Panicum miliaceum L. by using factorial based on randomized completely block design with three replications in Qaen region, Iran. The main treatments were municipal solid waste compost and cow manure (each at 0 and 25 t.ha-1 and sub treatments were elements of Zn (0, 50 kg.ha-1 and B (0, 10 kg.ha-1 using their respective ZnSO4 and H3BO3 salts. Results showed that treatments interaction had significant effects on total dry matter yield, number of tillers per plant and plant height of Millet. The highest total dry matter production was achieved by interaction of cow manure along with Zn and B elements. Concentrations of N, Fe, Zn, B and Cu in plant were increased significantly by treatments interaction effects compared to control. Interaction effect of organic fertilizers with B (in the absence of Zn enhanced plant B concentration significantly, whereas, interaction of organic fertilizers with Zn (in the absence of B decreased B concentration in plant. The highest plant uptake of N, P, K, Zn, and B was observed in plots with cow manure and Zn and B elements.

Selective deuteration illuminates the importance of tunneling in the unimolecular decay of Criegee intermediates to hydroxyl radical products.

Science.gov (United States)

Green, Amy M; Barber, Victoria P; Fang, Yi; Klippenstein, Stephen J; Lester, Marsha I

2017-11-21

Ozonolysis of alkenes, an important nonphotolytic source of hydroxyl (OH) radicals in the atmosphere, proceeds through unimolecular decay of Criegee intermediates. Here, we report a large kinetic isotope effect associated with the rate-limiting hydrogen-transfer step that releases OH radicals for a prototypical Criegee intermediate, CH 3 CHOO. IR excitation of selectively deuterated syn -CD 3 CHOO is shown to result in deuterium atom transfer and release OD radical products. Vibrational activation of syn -CD 3 CHOO is coupled with direct time-resolved detection of OD products to measure a 10-fold slower rate of unimolecular decay upon deuteration in the vicinity of the transition state barrier, which is confirmed by microcanonical statistical theory that incorporates quantum mechanical tunneling. The corresponding kinetic isotope effect of ∼10 is attributed primarily to the decreased probability of D-atom vs. H-atom transfer arising from tunneling. Master equation modeling is utilized to compute the thermal unimolecular decay rates for selectively and fully deuterated syn methyl-substituted Criegee intermediates under atmospheric conditions. At 298 K (1 atm), tunneling is predicted to enhance the thermal decay rate of syn -CH 3 CHOO compared with the deuterated species, giving rise to a significant kinetic isotope effect of ∼50.

Preliminary thermal sizing of intermediate heat exchanger for NHDD system

International Nuclear Information System (INIS)

Kim, Chan Soo; Hong, Sung Deok; Kim, Yong Wan; Chang, Jongh Wa

2009-01-01

Nuclear Hydrogen Development and Demonstration (NHDD) system is a Very High Temperature gascooled Reactor (VHTR) coupled with hydrogen production systems. Intermediate heat exchanger transfers heat from the nuclear reactor to the hydrogen production system. This study presented the sensitivity analysis on a preliminary thermal sizing of the intermediate heat exchanger. Printed Circuit Heat Exchanger (PCHE) was selected for the thermal sizing because the printed circuit heat exchanger has the largest compactness among the heat exchanger types. The analysis was performed to estimate the effect of key parameters including the operating condition of the intermediate system, the geometrical factors of the PCHE, and the working fluid of the intermediate system.

Intermediate mass distribution of the dual resonance pomeron

International Nuclear Information System (INIS)

Chiu, C.B.; Matsuda, S.

1978-01-01

The intermediate mass distribution of the dual resonance pomeron is determined at the one-loop level and it is shown that the mass distribution obtained is remarkably similar to a suitably defined mass distribution in the dual multiperipheral model. Thus it is suggestive to identify the intermediate states of the dual resonance pomeron with multiperipheral processes. (Auth.)

CONDITIONING OF INTERMEDIATE-LEVEL WASTE AT FORSCHUNGSZENTRUM JUELICH GMBH

International Nuclear Information System (INIS)

Krumbach, H.

2003-01-01

This contribution to the group of low-level, intermediate, mixed and hazardous waste describes the conditioning of intermediate-level mixed waste (dose rate above 10 mSv/h at the surface) from Research Centre Juelich (FZJ). Conditioning of the waste by supercompaction is performed at Research Centre Karlsruhe (FZK). The waste described is radioactive waste arising from research at Juelich. This waste includes specimens and objects from irradiation experiments in the research reactors Merlin (FRJ-1) and Dido (FRJ-2) at FZJ. In principle, radioactive waste at Forschungszentrum Juelich GmbH is differentiated by the surface dose rate at the waste package. Up to a surface dose rate of 10 mSv/h, the waste is regarded as low-level. The radioactive waste described here has a surface dose rate above 10 mSv/h. Waste up to 10 mSv/h is conditioned at the Juelich site according to different conditioning methods. The intermediate-level waste can only be conditioned by supercompaction in the processing facility for intermediate-level waste from plant operation at Research Centre Karlsruhe. Research Centre Juelich also uses this waste cell to condition its intermediate-level waste from plant operation

Surfing among species, populations and morphotypes: Inferring boundaries between two species of new world silversides (Atherinopsidae).

Science.gov (United States)

González-Castro, Mariano; Rosso, Juan José; Mabragaña, Ezequiel; Díaz de Astarloa, Juan Martín

2016-01-01

Atherinopsidae are widespread freshwater and shallow marine fish with singular economic importance. Morphological, genetical and life cycles differences between marine and estuarine populations were already reported in this family, suggesting ongoing speciation. Also, coexistence and interbreeding between closely related species were documented. The aim of this study was to infer boundaries among: (A) Odontesthes bonariensis and O. argentinensis at species level, and intermediate morphs; (B) the population of O. argentinensis of Mar Chiquita Lagoon and its marine conspecifics. To achieve this, we integrated, meristic, Geometrics Morphometrics and DNA Barcode approaches. Four groups were discriminated and subsequently characterized according to their morphological traits, shape and meristic characters. No shared haplotypes between O. bonariensis and O. argentinensis were found. Significative-meristic and body shape differences between the Mar Chiquita and marine individuals of O. argentinensis were found, suggesting they behave as well differentiated populations, or even incipient ecological species. The fact that the Odontesthes morphotypes shared haplotypes with both, O. argentinensis and O. bonariensis, but also possess meristic and morphometric distinctive traits open new questions related to the origin of this morphogroup. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Supersymmetry and intermediate symmetry breaking in SO(10) superunification

International Nuclear Information System (INIS)

Asatryan, H.M.; Ioannisyan, A.N.

1985-01-01

A scheme of simultaneous breakdown of intermediate symmetry SO(10) → SU(3)sub(c) x U(1) x SU(2)sub(L) x SU(2)sub(R) and supersymmetry by means of a single scale parameter is suggested. This intermediate symmetry, which is preferable physically, owing to the broken supersymmetry has a minimum lying lower than SU(4) x SU(2)sub(L) x SU(2)sub(R). The intermediate symmetry is broken by the vacuum expectation value of the Higgs superfields. Owing to the quantum corrections the potential minimum turns out to correspond to breakdown of the intermediate symmetry up to the standard group SU(3)sub(c) x SU(2)sub(L) x U(1)sub(y). The value of the Weinberg angle is less than that in the supersymmetric SU(5) model and agrees with the experiment

Biogeography of tropical Indo-West Pacific parasites: a cryptic species of Transversotrema and evidence for rarity of Transversotrematidae (Trematoda) in French Polynesia.

Science.gov (United States)

Cribb, Thomas H; Adlard, Robert D; Bray, Rodney A; Sasal, Pierre; Cutmore, Scott C

2014-04-01

We sought transversotrematid trematodes from French Polynesian fishes by examining 304 individual scaled fishes of 53 species from seven families known to harbour the family elsewhere. A single species was found at two locations in the Tuamotus Archipelago on two species of Chaetodontidae (Chaetodon auriga and Chaetodon ephippium) and one species of Lutjanidae (Lutjanus gibbus). The species closely resembles Transversotrema borboleta Hunter & Cribb, 2012 from chaetodontids and lutjanids of the northern Great Barrier Reef (GBR) but differs from it consistently in 8 base positions of ITS2 rDNA. This level of variation exceeds that between some clearly morphologically distinct pairs of species of Transversotrema and the form from French Polynesia is thus interpreted as a distinct, though cryptic, species and named Transversotrema polynesiae n. sp. The new species forms part of a complex of species, here characterised as the T. borboleta complex, associated with chaetodontids and lutjanids in the tropical Indo-West Pacific. Most of the putative species within this complex are yet to be described. Comparison of identical numbers of matched samples of fishes from French Polynesia, Heron Island (southern GBR) and Lizard Island (northern GBR) revealed 1, 4 and 10 species of Transversotrema respectively suggesting that the French Polynesian fauna is depauperate for this family. In addition to those species apparently missing from suitable hosts in French Polynesia, several species from further west infect fishes (especially Nemipteridae) that are themselves absent from French Polynesia. This dramatic east-west decline in richness contrasts strongly with what is known for monogeneans, which appear to maintain their richness over the same scale, and is more precipitate than is known for other groups of trematodes. The decline might be explained in part by the absence of the as yet unknown first intermediate hosts in French Polynesia. However, we predict that it is explained

Comparative Phylogenetic Studies on Schistosoma japonicum and Its Snail Intermediate Host Oncomelania hupensis: Origins, Dispersal and Coevolution.

Directory of Open Access Journals (Sweden)

Stephen W Attwood

Full Text Available Schistosoma japonicum causes major public health problems in China and the Philippines; this parasite, which is transmitted by freshwater snails of the species Oncomelania hupensis, causes the disease intestinal schistosomiasis in humans and cattle. Researchers working on Schistosoma in Africa have described the relationship between the parasites and their snail intermediate hosts as coevolved or even as an evolutionary arms race. In the present study this hypothesis of coevolution is evaluated for S. japonicum and O. hupensis. The origins and radiation of the snails and the parasite across China, and the taxonomic validity of the sub-species of O. hupensis, are also assessed.The findings provide no evidence for coevolution between S. japonicum and O. hupensis, and the phylogeographical analysis suggests a heterochronous radiation of the parasites and snails in response to different palaeogeographical and climatic triggers. The results are consistent with a hypothesis of East to West colonisation of China by Oncomelania with a re-invasion of Japan by O. hupensis from China. The Taiwan population of S. japonicum appears to be recently established in comparison with mainland Chinese populations.The snail and parasite populations of the western mountain region of China (Yunnan and Sichuan appear to have been isolated from Southeast Asian populations since the Pleistocene; this has implications for road and rail links being constructed in the region, which will breach biogeographical barriers between China and Southeast Asia. The results also have implications for the spread of S. japonicum. In the absence of coevolution, the parasite may more readily colonise new snail populations to which it is not locally adapted, or even new intermediate host species; this can facilitate its dispersal into new areas. Additional work is required to assess further the risk of spread of S. japonicum.

Characterization of extra-framework species in zeolites

DEFF Research Database (Denmark)

Andersen, Casper Welzel

Sometimes it is difficult to see the wood for the trees. Crystallography is a great tool to take a step back, to observe and analyze the effects and implications caused by atoms and molecules in a crystalline material. In catalysis, the goal is to uncover the chemical pathway from reactant...... zeolites for an in-depth structural exploration. The amount of information that can be retrieved using such excellent data is pushed to the limit. Finally, combined diffraction and absorption experiments were performed in situ on copper-loaded chabazite zeolite. Catalytic intermediate species...

Campo rupestre recém-queimado na Chapada Diamantina, Bahia, Brasil: plantas de rebrota e sementes, com espécies endêmicas na rocha Recently burnt 'campo rupestre' in the Chapada Diamantina, Bahia, Brazil: resprouters and seeders, with endemic rock species

Directory of Open Access Journals (Sweden)

Sâmia Paula Santos Neves

2010-09-01

conspicuous species and floristic similarities among sites with and without recent fire disturbance. A species census of all vascular plants in 16 plots (10x10 m was performed, and species cover was estimated in five subplots (2x2 m. 85 species were found, distributed among 34 families, including 11 monocotyledons, 22 eudicotyledons and one monilophyte. The most abundant specie was Panicum trinii Kunth (Poaceae and the most frequent was Periandra mediterranea (Vell. Taub (Fabaceae. The Shannon index was 3.4. The study area grouped with a rocky area at lower altitudes (38% similarity. Probably, fire is more frequent in these areas than on hill summits. The main dominant species resprouted from underground buds and from aerial organs. One of the most frequent species, Dactylaena microphylla Eichler, was established from seed. Fire-sensitive endemic species survive on vegetation islands on rocky outcrops.

Intermediate energy data

International Nuclear Information System (INIS)

Koning, A.J.; Fukahori, T.; Hasegawa, A.

1998-01-01

Subgroup 13 (SG13) on Intermediate Energy Nuclear data was formed by NEA Nuclear Science Committee to solve common problems of these types of data for nuclear applications. An overview is presented in this final report of the present activities of SG13, including data needs, high-priority nuclear data request list (nuclides), compilation of experimental data, specialists meetings and benchmarks, data formats and data libraries. Some important accomplishments are summarized, and recommendations are presented. (R.P.)

Has Banks’ Financial Intermediation Improved in Russia?

OpenAIRE

Fungachova, Z.; Solanko, L.

2010-01-01

The aim of this paper is to analyze the increasing importance of banks in the Russian economy over the period following the financial crisis of 1998. We use several measures to assess the role of banks in domestic financial intermediation in Russia. The traditional macro-level view is complemented by the analysis of sectoral financial flows as well as by insights from micro-level studies. All of these confirm that banks are becoming increasingly important in financial intermediation. We find ...

Corrosion susceptibility of steel drums to be used as containers for intermediate level nuclear waste

Science.gov (United States)

Farina, S.; Schulz Rodriguez, F.; Duffó, G.

2013-07-01

The present work is a study of the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins contaminated with different types and concentrations of aggressive species. A special type of specimen was manufactured to simulate the cemented ion-exchange resins in the drum. The evolution of the corrosion potential and the corrosion rate of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 900 days. The aggressive species studied were chloride ions (the main ionic species of concern) and sulphate ions (produced during radiolysis of the cationic exchange-resins after cementation). The work was complemented with an analysis of the corrosion products formed on the steel in each condition, as well as the morphology of the corrosion products. When applying the results obtained in the present work to estimate the corrosion depth of the steel drumscontaining the cemented radioactive waste after a period of 300 years (foreseen durability of the Intermediate Level Radioactive Waste facility in Argentina) , it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums.

Southern Ocean Surface and Intermediate Water Temperature from Alkenones and Mg/Ca of Infaunal Foraminifera for the last 1.5 Ma

Science.gov (United States)

Elmore, Aurora; McClymont, Erin; Elderfield, Harry; Kender, Sev

2014-05-01

The reconstruction of past surface (SST), intermediate, and deep-water temperatures is critical to our understanding of feedbacks within the ocean-climate system. Intermediate water temperature (IWT) reconstruction is particularly important since intermediate waters, including Antarctic Intermediate Water (AAIW), are proposed to be an important driver in high-low latitude teleconnections, despite limited intermediate-depth records through the Pliocene and Pleistocene. Paleotemperature proxies have caveats, including the 'Carbonate Ion Effect' on the Magnesium to Calcium ratio (Mg/Ca) of benthic foraminifera. However, recent studies demonstrated that the infaunal species, Uvigerina peregrina, co-precipitates Mg independent of secondary effects, affording the use of U.peregrina Mg/Ca as a paleotemperature proxy (Elderfield et al., 2010). We present the first 1.5 Ma record of IWT from Mg/CaU.peregrina coupled with an alkenone- derived UK37' SST record from a sediment core in the Southwest Pacific (DSDP site 593; 1068m water depth), in the core of modern AAIW. Our new data reconstruct interglacial IWTs at ~7°C before and after the Mid-Pleistocene Transition (MPT), whereas values of ~5°C occur in the later Pleistocene. Glacial IWT remained fairly constant (~2°C) throughout the last 1 Ma. These results are in apparent disagreement with the typical idea that glacial-interglacial temperature fluctuations were smaller in the '41-kyr world' before the MPT, than during the '100-kyr world', after the MPT. At proximal ODP site 1123 (3290m water depth; Elderfield et al., 2012), interglacial deepwater temperatures increase by ~1°C after the MPT, with relatively constant glacial deepwater temperatures (~-2°C) over the last 1 Ma. New results from DSDP 593 therefore imply that the mechanisms that drive intermediate and deep water temperatures varied, suggesting that at least one of these watermasses has properties driven by something other than Northern Hemisphere glaciation

Anther and pollen development in some species of Poaceae (Poales

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AT. Nakamura

Full Text Available Anther and pollen development were studied in Olyra humilis Nees, Sucrea monophylla Soderstr, (Bambusoideae, Axonopus aureus P. Beauv., Paspalum polyphyllum Nees ex Trin. (Panicoideae, Eragrostis solida Nees, and Chloris elata Desv. (Chloridoideae. The objective of this study was to characterise, embryologically, these species of subfamilies which are considered basal, intermediate and derivate, respectively. The species are similar to each other and to other Poaceae. They present the following characters: tetrasporangiate anthers; monocotyledonous-type anther wall development, endothecium showing annular thickenings, secretory tapetum; successive microsporogenesis; isobilateral tetrads; spheroidal, tricellular, monoporate pollen grains with annulus and operculum. Nevertheless, the exine patterns of the species studied are distinct. Olyra humilis and Sucrea monophylla (Bambusoideae show a granulose pattern, whereas in the other species, it is insular. In addition, Axonopus aureus and Paspalum polyphyllum (Panicoideae have a compactly insular spinule pattern, while Chloris elata and Eragrostis solida (Chloridoideae show a sparsely insular spinule pattern. The exine ornamentation may be considered an important feature at the infrafamiliar level.

A low stringency polymerase chain reaction approach to the identification of Biomphalaria glabrata and B. tenagophila, intermediate snail hosts of Schistosoma mansoni in Brazil

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Teofânia HDA Vidigal

1996-12-01

Full Text Available The low stringency-polymerase chain reaction (LS-PCR with a pair of specific primers for the amplification of the 18S rRNA gene was evaluated as a means of differentiating between the two Schistosoma mansoni intermediate host species in Brazil: Biomphalaria glabrata and B. tenagophila. Individual snails obtained from different states of Brazil were used and the amplification patterns obtained showed a high degree of genetic variability in these species. Nevertheless, 4 and 3 clearly defined specific diagnostic bands was observed in individuals from B. glabrata and B. tenagophila respectively. The detection of snail specific diagnostic bands suggests the possibility of reliable species differentiation at the DNA level using LS-PCR.

An evaluation of Panicum maximum cv. Gatton: 2. The influence of ...

African Journals Online (AJOL)

Unknown

Saliva was removed through a ..... Solubility of the protein of tropical pasture species and the rate of digestion in the rumen. Anim. .... utilization of metabolizable energy and apparent absorption of amino acids in sheep given spring- and.

Distribution of Plasmids in Distinct Leptospira Pathogenic Species.

Science.gov (United States)

Wang, Yanzhuo; Zhuang, Xuran; Zhong, Yi; Zhang, Cuicai; Zhang, Yan; Zeng, Lingbing; Zhu, Yongzhang; He, Ping; Dong, Ke; Pal, Utpal; Guo, Xiaokui; Qin, Jinhong

2015-11-01

Leptospirosis, caused by pathogenic Leptospira, is a worldwide zoonotic infection. The genus Leptospira includes at least 21 species clustered into three groups--pathogens, non-pathogens, and intermediates--based on 16S rRNA phylogeny. Research on Leptospira is difficult due to slow growth and poor transformability of the pathogens. Recent identification of extrachromosomal elements besides the two chromosomes in L. interrogans has provided new insight into genome complexity of the genus Leptospira. The large size, low copy number, and high similarity of the sequence of these extrachromosomal elements with the chromosomes present challenges in isolating and detecting them without careful genome assembly. In this study, two extrachromosomal elements were identified in L. borgpetersenii serovar Ballum strain 56604 through whole genome assembly combined with S1 nuclease digestion following pulsed-field gel electrophoresis (S1-PFGE) analysis. Further, extrachromosomal elements in additional 15 Chinese epidemic strains of Leptospira, comprising L. borgpetersenii, L. weilii, and L. interrogans, were successfully separated and identified, independent of genome sequence data. Southern blot hybridization with extrachromosomal element-specific probes, designated as lcp1, lcp2 and lcp3-rep, further confirmed their occurrences as extrachromosomal elements. In total, 24 plasmids were detected in 13 out of 15 tested strains, among which 11 can hybridize with the lcp1-rep probe and 11 with the lcp2-rep probe, whereas two can hybridize with the lcp3-rep probe. None of them are likely to be species-specific. Blastp search of the lcp1, lcp2, and lcp3-rep genes with a nonredundant protein database of Leptospira species genomes showed that their homologous sequences are widely distributed among clades of pathogens but not non-pathogens or intermediates. These results suggest that the plasmids are widely distributed in Leptospira species, and further elucidation of their biological

Heterophobia: Subverting Heterosexual Hegemony through Intermedial Applied Performance for Young People

Science.gov (United States)

Phillips, Hannah

2016-01-01

This article responds to intermediality through a case study of an intermedial applied performance for young people. "Heterophobia," a hybrid fusion of live performance, digital technology, social media and urban street art, aimed to challenge homophobia in schools and online. Intermediality was used as a tool to enhance young people's…

42 CFR 54a.12 - Treatment of intermediate organizations.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Treatment of intermediate organizations. 54a.12... CHARITABLE CHOICE REGULATIONS APPLICABLE TO STATES, LOCAL GOVERNMENTS AND RELIGIOUS ORGANIZATIONS RECEIVING... ABUSE PREVENTION AND TREATMENT SERVICES § 54a.12 Treatment of intermediate organizations. If a...

Financial Intermediation and the Nigerian Economy: A Time Series ...

African Journals Online (AJOL)

... and cointegration analysis based on Engle Granger cointegration theory and error correction methodology, we tested both short and long run relationships between financial intermediation and economic growth in Nigeria. The result revealed that a long–run relationship exists between financial intermediation and growth ...

Borderline Personality Disorder in an Intermediate Psychological Therapies Service

Science.gov (United States)

Ryan, Seamus; Danquah, Adam N.; Berry, Katherine; Hopper, Mary

2017-01-01

The intermediate psychological therapies service is provided for individuals referred with common mental health problems within the primary care psychological therapies service, but whose difficulties are longstanding and/or complex. The prevalence of borderline personality disorder (BPD) in intermediate psychological therapy services has not been…

General educational disciplines practice-oriented training in intermediate vocational education

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Liya G. Skorobogatova

2011-01-01

Full Text Available The article concerns crucial issues of practice-oriented training in Russia's intermediate vocational education, designates directions of general educational disciplines study in intermediate vocational education.

Intermediate inflation from a non-canonical scalar field

Energy Technology Data Exchange (ETDEWEB)

Rezazadeh, K.; Karami, K. [Department of Physics, University of Kurdistan, Pasdaran St., Sanandaj (Iran, Islamic Republic of); Karimi, P., E-mail: rezazadeh86@gmail.com, E-mail: KKarami@uok.ac.ir, E-mail: parvin.karimi67@yahoo.com [Center for Excellence in Astronomy and Astrophysics (CEAA-RIAAM), P.O. Box 55134-441, Maragha (Iran, Islamic Republic of)

2015-09-01

We study the intermediate inflation in a non-canonical scalar field framework with a power-like Lagrangian. We show that in contrast with the standard canonical intermediate inflation, our non-canonical model is compatible with the observational results of Planck 2015. Also, we estimate the equilateral non-Gaussianity parameter which is in well agreement with the prediction of Planck 2015. Then, we obtain an approximation for the energy scale at the initial time of inflation and show that it can be of order of the Planck energy scale, i.e. M{sub P} ∼ 10{sup 18}GeV. We will see that after a short period of time, inflation enters in the slow-roll regime that its energy scale is of order M{sub P}/100 ∼ 10{sup 16}GeV and the horizon exit takes place in this energy scale. We also examine an idea in our non-canonical model to overcome the central drawback of intermediate inflation which is the fact that inflation never ends. We solve this problem without disturbing significantly the nature of the intermediate inflation until the time of horizon exit.

Estimation of intermediate grade uranium resources. Final report

International Nuclear Information System (INIS)

Lambie, F.W.; Kendall, G.R.; Klahn, L.J.; Davis, J.C.; Harbaugh, J.W.

1980-12-01

The purpose of this project is to analyze the technique currently used by DOE to estimate intermediate grade uranium (0.01 to 0.05% U 3 O 8 ) and, if possible, suggest alternatives to improve the accuracy and precision of the estimate. There are three principal conclusions resulting from this study. They relate to the quantity, distribution and sampling of intermediate grade uranium. While the results of this study must be validated further, they indicate that DOE may be underestimating intermediate level reserves by 20 to 30%. Plots of grade of U 3 O 8 versus tonnage of ore and tonnage U 3 O 8 indicate grade-tonnage relationships that are essentially log-linear, at least down to 0.01% U 3 O 8 . Though this is not an unexpected finding, it may provide a technique for reducing the uncertainty of intermediate grade endowment. The results of this study indicate that a much lower drill hole density is necessary for DOE to estimate uranium resources than for a mining company to calculate ore resources. Though errors in local estimates will occur, they will tend to cancel over the entire deposit

Structure of replicating intermediates of human herpesvirus type 6

International Nuclear Information System (INIS)

Severini, Alberto; Sevenhuysen, Claire; Garbutt, Michael; Tipples, Graham A.

2003-01-01

We have studied the structure of the replicative intermediates of human herpesvirus 6 (HHV-6) using pulsed-field gel electrophoresis, partial digestion, two-dimensional gel electrophoresis, and sedimentation centrifugation. The results show that DNA replication of HHV-6 produces head-to-tail concatemeric intermediates as well as approximately equal amounts of circular monomers or oligomers. Unlike the situation in herpes simplex virus, the intermediates of human herpesvirus 6 replication are not highly branched, suggesting a difference in the mechanism of replication or a lower frequency of homologous recombination in human herpesvirus 6 compared to herpes simplex virus

Proteomic characterization of intermediate and advanced glycation end-products in commercial milk samples.

Science.gov (United States)

Renzone, Giovanni; Arena, Simona; Scaloni, Andrea

2015-03-18

The Maillard reaction consists of a number of chemical processes affecting the structure of the proteins present in foods. We previously accomplished the proteomic characterization of the lactosylation targets in commercial milk samples. Although characterizing the early modification derivatives, this analysis did not describe the corresponding advanced glycation end-products (AGEs), which may be formed from the further oxidation of former ones or by reaction of oxidized sugars with proteins, when high temperatures are exploited. To fill this gap, we have used combined proteomic procedures for the systematic characterization of the lactosylated and AGE-containing proteins from the soluble and milk fat globule membrane fraction of various milk products. Besides to confirm all lactulosyl-lysines described previously, 40 novel lactosylation sites were identified. More importantly, 308 additional intermediate and advanced glyco-oxidation derivatives (including cross-linking adducts) were characterized in 31 proteins, providing the widest qualitative inventory of modified species ascertained in commercial milk samples so far. Amadori adducts with glucose/galactose, their dehydration products, carboxymethyllysine and glyoxal-, 3-deoxyglucosone/3-deoxygalactosone- and 3-deoxylactosone-derived dihydroxyimidazolines and/or hemiaminals were the most frequent derivatives observed. Depending on thermal treatment, a variable number of modification sites was identified within each protein; their number increased with harder food processing conditions. Among the modified proteins, species involved in assisting the delivery of nutrients, defense response against pathogens and cellular proliferation/differentiation were highly affected by AGE formation. This may lead to a progressive decrease of the milk nutritional value, as it reduces the protein functional properties, abates the bioavailability of the essential amino acids and eventually affects food digestibility. These aspects

Mechanisms of deterioration of intermediate moisture food systems

Science.gov (United States)

Labuza, T. P.

1972-01-01

A study of shelf stability in intermediate moisture foods was made. Major efforts were made to control lipid oxidation and nonenzymatic browning. In order to determine means of preventing these reactions, model systems were developed having the same water activity content relationship of intermediate moisture foods. Models were based on a cellulose-lipid and protein-lipid system with glycerol added as the humectant. Experiments with both systems indicate that lipid oxidation is promoted significantly in the intermediate moisture range. The effect appeared to be related to increased mobility of either reactants or catalysts, since when the amount of water in the system reached a level where capillary condensation occurred and thus free water was present, the rates of oxidation increased. With added glycerol, which is water soluble and thus increases the amount of mobile phase, the increase in oxidation rate occurs at a lower relative humidity. The rates of oxidation were maximized at 61% RH and decreased again at 75% RH probably due to dilution. No significant non-enzymatic browning occurred in the protein-lipid systems. Prevention of oxidation by the use of metal chelating agents was enhanced in the cellulose system, whereas, with protein present, the lipid soluble chain terminating antioxidants (such as BHA) worked equally as well. Preliminary studies of foods adjusted to the intermediate moisture range bear out the results of oxidation in model systems. It can be concluded that for most fat containing intermediate moisture foods, rancidity will be the reaction most limiting stability.

Molecular identification of two Culex (Culex species of the neotropical region (Diptera: Culicidae.

Directory of Open Access Journals (Sweden)

Magdalena Laurito

Full Text Available Culex bidens and C. interfor, implicated in arbovirus transmission in Argentina, are sister species, only distinguishable by feature of the male genitalia; however, intermediate specimens of the species in sympatry have been found. Fourth-instar larvae and females of both species share apomorphic features, and this lack of clear distinction creates problems for specific identification. Geometric morphometric traits of these life stages also do not distinguish the species. The aim of the present study was to assess the taxonomic status of C. bidens and C. interfor using two mitochondrial genes and to determine the degree of their reproductive isolation using microsatellite loci. Sequences of the ND4 and COI genes were concatenated in a matrix of 993 nucleotides and used for phylogenetic and distance analyses. Bayesian and maximum parsimony inferences showed a well resolved and supported topology, enclosing sequences of individuals of C. bidens (0.83 BPP, 73 BSV and C. interfor (0.98 BPP, 97 BSV in a strong sister relationship. The mean K2P distance within C. bidens and C. interfor was 0.3% and 0.2%, respectively, and the interspecific variation was 2.3%. Bayesian clustering also showed two distinct mitochondrial lineages. All sequenced mosquitoes were successfully identified in accordance with the best close match algorithm. The low genetic distance values obtained indicate that the species diverged quite recently. Most morphologically intermediate specimens of C. bidens from Córdoba were heterozygous for the microsatellite locus GT51; the significant heterozygote excess observed suggests incomplete reproductive isolation. However, C. bidens and C. interfor should be considered good species: the ventral arm of the phallosome of the male genitalia and the ND4 and COI sequences are diagnostic characters.

Reinforced concrete in the intermediable-level nuclear waste repository

International Nuclear Information System (INIS)

Duffo, Gustavo

2009-01-01

The National Atomic Energy Commission (CNEA) is responsible for developing the nuclear waste disposal management programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The proposed model is a near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers and the model foresees a period of 300 years of institutional post-closure control. Since the vault and cover are major components of the engineered barriers, the durability of these concrete structures is an important aspect for the facility integrity. This work presents laboratory investigations performed on the corrosion susceptibility of steel rebars embedded in two different types of high performance reinforced concretes, recently developed by the National Institute of Industrial Technology (Argentine). Concretes were made with cement with Blast Furnace Slag (CAH) and Silica Fume cement (CAH + SF). The aim of this work is to predict the service life of the intermediate level radioactive waste disposal vaults from data obtained from electrochemical techniques. Besides, the diffusion coefficients of aggressive species, such as chloride and carbon dioxide, were also determined. On the other hand, data obtained with corrosion sensors embedded in a vault prototype is also included. These sensors allow on-line measurements of several parameters related to the corrosion process such as rebar corrosion potential and corrosion current density; incoming oxygen flow that reaches the metal surface; concrete electrical resistivity; chloride concentration and internal concrete temperature. All the information obtained from both, laboratory tests and sensors will be used for the final design of the container in order to achieve a service life more or equal than the foreseen durability for this type of

CIAS detection of Fasciola hepatica/F. gigantica intermediate forms in bovines from Bangladesh.

Science.gov (United States)

Ahasan, Syed Ali; Valero, M Adela; Chowdhury, Emdadul Haque; Islam, Mohammad Taohidul; Islam, Mohammad Rafiqul; Hussain Mondal, Mohammad Motahar; Peixoto, Raquel V; Berinde, Lavinia; Panova, Miroslava; Mas-Coma, Santiago

2016-03-01

Fascioliasis is an important food-borne parasitic zoonosis caused by two trematode species, Fasciola hepatica and Fasciola gigantica. The characterisation and differentiation of Fasciola populations is crucial to control the disease, given the different transmission, epidemiology and pathology characteristics of the two species. Lineal biometric features of adult liver flukes infecting livestock have been studied to characterise and discriminate fasciolids from Bangladesh. An accurate analysis was conducted to phenotypically discriminate between fasciolids from naturally infected bovines (cattle, buffaloes) throughout the country. Morphometric analyses were made with a computer image analysis system (CIAS) applied on the basis of standardised measurements and the logistic model of the body growth and development of fasciolids in the different host groups. Since it is the first ever comprehensive study of this kind undertaken in Bangladesh, the results are compared to pure fasciolid populations of F. hepatica from the European Mediterranean area and F. gigantica from Burkina Faso, geographical areas where both species do not co-exist. Principal component analysis showed that the biometric characteristics of fasciolids from Bangladesh are situated between F. hepatica and F. gigantica standard populations, indicating the presence of phenotypes of intermediate forms in Bangladesh. These results are analysed by considering the present emergence of animal fascioliasis, the local lymnaeid fauna, the impact of climate change, and the risk of human infection in the country.

Mediterranean intermediate circulation estimated from Argo data in 2003–2010

Directory of Open Access Journals (Sweden)

M. Menna

2010-03-01

Full Text Available Data from 38 Argo profiling floats are used to describe the intermediate Mediterranean currents for the period October 2003–January 2010. These floats were programmed to execute 5-day cycles, to drift at a neutral parking depth of 350 m and measure temperature and salinity profiles from either 700 or 2000 m up to the surface. At the end of each cycle the floats remained at the sea surface for about 6 h, enough time to be localised and transmit the data to the Argos satellite system. The Argos positions were used to determine the float surface and intermediate displacements. At the surface, the float motion was approximated by a linear displacement and inertial motion. Intermediate velocities estimates were used to investigate the Mediterranean circulation at 350 m, to compute the pseudo-Eulerian statistics and to study the influence of bathymetry on the intermediate currents. Maximum speeds, as large as 33 cm/s, were found northeast of the Balearic Islands (western basin and in the Ierapetra eddy (eastern basin. Typical speeds in the main along-slope currents (Liguro-Provençal-Catalan, Algerian and Libyo-Egyptian Currents were ~20 cm/s. In the central and western part of Mediterranean basin, the pseudo-Eulerian statistics show typical intermediate circulation pathways which can be related to the motion of Levantine Intermediate Water. In general our results agree with the qualitative intermediate circulation schemes proposed in the literature, except in the southern Ionian where we found westward-flowing intermediate currents. Fluctuating currents appeared to be usually larger than the mean flow. Intermediate currents were found to be essentially parallel to the isobaths over most of the areas characterized by strong bathymetry gradients, in particular, in the vicinity of the continental slopes.

Intermediate Collaborative Adaptive Management Strategies Build Stakeholder Capacity

Directory of Open Access Journals (Sweden)

Martha C. Monroe

2013-06-01

Full Text Available Efforts to implement collaborative adaptive management (CAM often suffer from challenges, such as an unwillingness of managers to share power, unresolved conflicts between stakeholders, and lack of capacity among stakeholders. Some aspects considered essential to CAM, e.g., trust and stakeholder capacity, may be more usefully viewed as goals for intermediate strategies rather than a set of initial conditions. From this perspective, intermediate steps that focus on social learning and building experience could overcome commonly cited barriers to CAM. An exploration of Springs Basin Working Groups, organized around major clusters of freshwater springs in north Florida, provides a case study of how these intermediate steps enable participants to become more reasonable and engaged. This strategy may be easily implemented by agencies beginning a CAM process.

Formation of intermediate shocks in both two-fluid and hybrid models

International Nuclear Information System (INIS)

Wu, C.C.; Hada, T.

1991-01-01

Intermediate shocks are shocks with shock frame fluid velocities greater than the Alfven speed ahead and less than the Alfven speed behind, or equivalently, across intermediate shocks the sign of the transverse component of the magnetic field changes. These shocks had been considered extraneous, or nonevolutionary, or unstable, and they had been thought not to correspond to physical reality [Germain, 1960; Jeffrey and Taniuti, 1964; Kantrowitz and Petschek, 1966]. However, it has been shown that intermediate shocks can be formed from continuous waves according to dissipative magnetohydrodynamics (MHD) [Wu, 1987, 1988a, b, 1990]. Thus according to the formation argument which requires that physical shocks be formed by the wave steepening process, the intermediate shocks should be considered physical. Here, intermediate shocks are studied in a two-fluid model that includes finite ion inertia dispersion and in a hybrid model in which the full ion dynamics is retained while the electrons are treated as a massless fluid. The authors show that in both models intermediate shocks can be formed through wave steepening, meaning that they are stable and possess shock structures

Leptospira species in floodwater during the 2011 floods in the Bangkok Metropolitan Region, Thailand.

Science.gov (United States)

Thaipadungpanit, Janjira; Wuthiekanun, Vanaporn; Chantratita, Narisara; Yimsamran, Surapon; Amornchai, Premjit; Boonsilp, Siriphan; Maneeboonyang, Wanchai; Tharnpoophasiam, Prapin; Saiprom, Natnaree; Mahakunkijcharoen, Yuvadee; Day, Nicholas P J; Singhasivanon, Pratap; Peacock, Sharon J; Limmathurotsakul, Direk

2013-10-01

Floodwater samples (N = 110) collected during the 2011 Bangkok floods were tested for Leptospira using culture and polymerase chain reaction (PCR); 65 samples were PCR-positive for putatively non-pathogenic Leptospira species, 1 sample contained a putatively pathogenic Leptospira, and 6 samples contained Leptospira clustering phylogenetically with the intermediate group. The low prevalence of pathogenic and intermediate Leptospira in floodwater was consistent with the low number of human leptospirosis cases reported to the Bureau of Epidemiology in Thailand. This study provides baseline information on environmental Leptospira in Bangkok together with a set of laboratory tests that could be readily deployed in the event of future flooding.

Quantification of the Keto-Hydroperoxide (HOOCH2OCHO) and Other Elusive Intermediates during Low-Temperature Oxidation of Dimethyl Ether

KAUST Repository

Moshammer, Kai

2016-09-17

This work provides new temperature-dependent mole fractions of elusive intermediates relevant to the low-temperature oxidation of dimethyl ether (DME). It extends the previous study of Moshammer et al. [ J. Phys. Chem. A 2015, 119, 7361–7374] in which a combination of a jet-stirred reactor and molecular beam mass spectrometry with single-photon ionization via tunable synchrotron-generated vacuum-ultraviolet radiation was used to identify (but not quantify) several highly oxygenated species. Here, temperature-dependent concentration profiles of 17 components were determined in the range of 450–1000 K and compared to up-to-date kinetic modeling results. Special emphasis is paid toward the validation and application of a theoretical method for predicting photoionization cross sections that are hard to obtain experimentally but essential to turn mass spectral data into mole fraction profiles. The presented approach enabled the quantification of the hydroperoxymethyl formate (HOOCH2OCH2O), which is a key intermediate in the low-temperature oxidation of DME. The quantification of this keto-hydroperoxide together with the temperature-dependent concentration profiles of other intermediates including H2O2, HCOOH, CH3OCHO, and CH3OOH reveals new opportunities for the development of a next-generation DME combustion chemistry mechanism.

Alkyne Hydroamination and Trimerization with Titanium Bis(phenolate)pyridine Complexes: Evidence for Low-Valent Titanium Intermediates and Synthesis of an Ethylene Adduct of Titanium(II)

KAUST Repository

Tonks, Ian A.

2013-06-24

A class of titanium precatalysts of the type (ONO)TiX2 (ONO = pyridine-2,6-bis(4,6-di-tert-butylphenolate); X = Bn, NMe2) has been synthesized and crystallographically characterized. The (ONO)TiX2 (X = Bn, NMe2, X2 = NPh) complexes are highly active precatalysts for the hydroamination of internal alkynes with primary arylamines and some alkylamines. A class of titanium imido/ligand adducts, (ONO)Ti(L)(NR) (L = HNMe2, py; R = Ph, tBu), have also been synthesized and characterized and provide structural analogues to intermediates on the purported catalytic cycle. Furthermore, these complexes exhibit unusual redox behavior. (ONO)TiBn2 (1) promotes the cyclotrimerization of electron-rich alkynes, likely via a catalytically active TiII species that is generated in situ from 1. Depending on reaction conditions, these TiII species are proposed to be generated through Ti benzylidene or imido intermediates. A formally TiII complex, (ONO)Ti II(η2-C2H4)(HNMe2) (7), has been prepared and structurally characterized. © 2013 American Chemical Society.

Alkyne Hydroamination and Trimerization with Titanium Bis(phenolate)pyridine Complexes: Evidence for Low-Valent Titanium Intermediates and Synthesis of an Ethylene Adduct of Titanium(II)

KAUST Repository

Tonks, Ian A.; Meier, Josef C.; Bercaw, John E.

2013-01-01

A class of titanium precatalysts of the type (ONO)TiX2 (ONO = pyridine-2,6-bis(4,6-di-tert-butylphenolate); X = Bn, NMe2) has been synthesized and crystallographically characterized. The (ONO)TiX2 (X = Bn, NMe2, X2 = NPh) complexes are highly active precatalysts for the hydroamination of internal alkynes with primary arylamines and some alkylamines. A class of titanium imido/ligand adducts, (ONO)Ti(L)(NR) (L = HNMe2, py; R = Ph, tBu), have also been synthesized and characterized and provide structural analogues to intermediates on the purported catalytic cycle. Furthermore, these complexes exhibit unusual redox behavior. (ONO)TiBn2 (1) promotes the cyclotrimerization of electron-rich alkynes, likely via a catalytically active TiII species that is generated in situ from 1. Depending on reaction conditions, these TiII species are proposed to be generated through Ti benzylidene or imido intermediates. A formally TiII complex, (ONO)Ti II(η2-C2H4)(HNMe2) (7), has been prepared and structurally characterized. © 2013 American Chemical Society.

The Case for Adopting the “Species Complex” Nomenclature for the Etiologic Agents of Cryptococcosis

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Kyung J. Kwon-Chung

2017-01-01

Full Text Available Cryptococcosis is a potentially lethal disease of humans/animals caused by Cryptococcus neoformans and Cryptococcus gattii. Distinction between the two species is based on phenotypic and genotypic characteristics. Recently, it was proposed that C. neoformans be divided into two species and C. gattii into five species based on a phylogenetic analysis of 115 isolates. While this proposal adds to the knowledge about the genetic diversity and population structure of cryptococcosis agents, the published genotypes of 2,606 strains have already revealed more genetic diversity than is encompassed by seven species. Naming every clade as a separate species at this juncture will lead to continuing nomenclatural instability. In the absence of biological differences between clades and no consensus about how DNA sequence alone can delineate a species, we recommend using “Cryptococcus neoformans species complex” and “C. gattii species complex” as a practical intermediate step, rather than creating more species. This strategy recognizes genetic diversity without creating confusion.

A new intermediate for the production of flexible stable polymers

Science.gov (United States)

Webster, J. A.

1973-01-01

Method of incorporating ether linkages into perfluoroalkylene segment of a dianydride intermediate yields intermediate that may be used in synthesis of flexible, stable polyimides for use as high-temperature, solvent-resistant sealants.

Intermediate heat exchanger for HTR process heat application

International Nuclear Information System (INIS)

Crambes, M.

1980-01-01

In the French study on the nuclear gasification of coal, the following options were recommended: Coal hydrogenation, the hydrogen being derived from CH 4 reforming under the effects of HTR heat; the use of an intermediate helium circuit between the nuclear plant and the reforming plant. The purpose of the present paper is to describe the heat exchanger designed to transfer heat from the primary to the intermediate circuit

Fatores limitantes ao crescimento do capim-Tanzânia em um sistema agrossilvipastoril com eucalipto, na região dos Cerrados de Minas Gerais Factors limiting the growth of Panicum maximum cv. Tanzânia-1 in an agrosilvopastoral system with eucalypt, in the Cerrados of Minas Gerais, Brazil

Directory of Open Access Journals (Sweden)

Carlos Mauricio Soares de Andrade

2001-07-01

Full Text Available Conduziu-se um estudo em um sistema agrossilvipastoril, constituído por Eucalyptus urophylla e Panicum maximum cv. Tanzânia-1, para verificar a hipótese de que existiam outros fatores, além da baixa disponibilidade de luz, interferindo no crescimento normal da gramínea, quatro anos após sua introdução no sistema. O estudo consistiu de um ensaio de adubação NPK a campo, adotando-se o delineamento experimental de blocos casualizados, com os tratamentos dispostos no arranjo fatorial 2³, com duas doses de nitrogênio (0 e 100 kg/ha de N, fósforo (0 e 70 kg/ha de P2O5 e potássio (0 e 100 kg/ha de K2O. A gramínea não respondeu ao P nem ao K, embora os teores originais de P e K disponíveis no solo fossem baixos. A adubação nitrogenada dobrou a taxa de acumulação de matéria seca do sub-bosque, mostrando que o crescimento da gramínea estava sendo restringido pela baixa disponibilidade de N no solo. A elevada resposta à adubação nitrogenada mostrou que o sombreamento não era o único fator limitando a produtividade do sub-bosque, e, também, que as plantas estabelecidas do capim-tanzânia não estavam sendo afetadas negativa e significativamente por substâncias alelopáticas produzidas pelo eucalipto.A study was conducted in an agrosilvopastoral system, constituted by Eucalyptus urophylla and Panicum maximum cv. Tanzânia-1, to verify the hypothesis that there were other factors, besides the low light availability, affecting the normal growth of the grass, four years after its introduction in the system. A NPK fertilization field trial was carry out, using the randomized block design, with the treatments in the 2³ factorial outline, with two doses of nitrogen (0 and 100 kg/ha of N, phosphorus (0 and 70 kg/ha of P2O5 and potassium (0 and 100 kg/ha of K2O. The grass did not respond to P nor K fertilization, in spite of the low original P and K availability in the soil. However, with the application of nitrogen the rate of herbage

Shelf stable intermediate moisture fruit cubes using radiation technology

International Nuclear Information System (INIS)

Mishra, Bibhuti B.; Saxena, Sudhanshu; Gautam, Satyendra; Chander, Ramesh; Sharma, Arun

2009-01-01

A process has been developed to prepare shelf stable ready-to-eat (RTE) intermediate moisture pineapple slices and papaya cubes using radiation technology. The combination of hurdles including osmotic dehydration, blanching, infrared drying, and gamma radiation dose of 1 kGy successfully reduced the microbial load to below detectable limit. The shelf life of the intermediate moisture pineapple slices and papaya cubes was found to be 40 days at ambient temperature (28 ± 2 deg C). The control samples spoiled within 6 days. The RTE intermediate moisture fruit products were found to have good texture, colour and sensory acceptability during this 40 days storage. (author)

Developmental stages of fish blood flukes, Cardicola forsteri and Cardicola opisthorchis (Trematoda: Aporocotylidae), in their polychaete intermediate hosts collected at Pacific bluefin tuna culture sites in Japan.

Science.gov (United States)

Ogawa, Kazuo; Shirakashi, Sho; Tani, Kazuki; Shin, Sang Phil; Ishimaru, Katsuya; Honryo, Tomoki; Sugihara, Yukitaka; Uchida, Hiro'omi

2017-02-01

Farming of Pacific bluefin tuna (PBT), Thunnus orientalis, is a rapidly growing industry in Japan. Aporocotylid blood flukes of the genus Cardicola comprising C. orientalis, C. opisthorchis and C. forsteri are parasites of economic importance for PBT farming. Recently, terebellid polychaetes have been identified as the intermediate hosts for all these parasites. We collected infected polychaetes, Terebella sp., the intermediate host of C. opisthorchis, from ropes and floats attached to tuna cages in Tsushima, Nagasaki Prefecture, Japan. Also, Neoamphitrite vigintipes (formerly as Amphitrite sp. sensu Shirakashi et al., 2016), the intermediate host of C. forsteri, were collected from culture cages in Kushimoto, Wakayama Prefecture, Japan. The terebellid intermediate hosts harbored the sporocysts and cercariae in their body cavity. Developmental stages of these blood flukes were molecularly identified using species specific PCR primers. In this paper, we describe the cercaria and sporocyst stages of C. opisthorchis and C. forsteri and compare their morphological characteristics among three Cardicola blood flukes infecting PBT. We also discuss phylogenetic relations of the six genera of the terebellid intermediate hosts (Artacama, Lanassa, Longicarpus, Terebella, Nicolea and Neoamphitrite) of blood flukes infecting marine fishes, based on their morphological characters. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genetic diversity and genomic resources available for the small millet crops to accelerate a New Green Revolution

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Travis Luc Goron

2015-03-01

Full Text Available Small millets are nutrient-rich food sources traditionally grown and consumed by subsistence farmers in Asia and Africa. They include finger millet (Eleusine coracana, foxtail millet (Setaria italica, kodo millet (Paspalum scrobiculatum, proso millet (Panicum miliaceum, barnyard millet (Echinochloa spp., and little millet (Panicum sumatrense. Local farmers value the small millets for their nutritional and health, tolerance to extreme stress including drought, and ability to grow under low nutrient input conditions, ideal in an era of climate change and steadily depleting natural resources. Little scientific attention has been paid to these crops, hence they have been termed orphan cereals. Despite this challenge, an advantageous quality of the small millets is that they continue to be grown in remote regions of the world which has preserved their biodiversity, providing breeders with unique alleles for crop improvement. The purpose of this review, first, is to highlight the diverse traits of each small millet species that are valued by farmers and consumers (e.g. nutritional quality which hold potential for selection, improvement or mechanistic study. For each species, the germplasm, genetic and genomic resources available will then be described as potential tools to exploit this biodiversity. The review will conclude with noting current trends and gaps in the literature and make recommendations on how to better preserve and utilize diversity within these species to accelerate a New Green Revolution for subsistence farmers in Asia and Africa.

Material Voices: Intermediality and Autism

Science.gov (United States)

Trimingham, Melissa; Shaughnessy, Nicola

2016-01-01

Autism continues to be regarded enigmatically; a community that is difficult to access due to perceived disruptions of interpersonal connectedness. Through detailed observations of two children participating in the Arts and Humanities Research Council funded project "Imagining Autism: Drama, Performance and Intermediality as Interventions for…

Insignificant disease among men with intermediate-risk prostate cancer.

Science.gov (United States)

Hong, Sung Kyu; Vertosick, Emily; Sjoberg, Daniel D; Scardino, Peter T; Eastham, James A

2014-12-01

A paucity of data exists on the insignificant disease potentially suitable for active surveillance (AS) among men with intermediate-risk prostate cancer (PCa). We tried to identify pathologically insignificant disease and its preoperative predictors in men who underwent radical prostatectomy (RP) for intermediate-risk PCa. We analyzed data of 1,630 men who underwent RP for intermediate-risk disease. Total tumor volume (TTV) data were available in 332 men. We examined factors associated with classically defined pathologically insignificant cancer (organ-confined disease with TTV ≤0.5 ml with no Gleason pattern 4 or 5) and pathologically favorable cancer (organ-confined disease with no Gleason pattern 4 or 5) potentially suitable for AS. Decision curve analysis was used to assess clinical utility of a multivariable model including preoperative variables for predicting pathologically unfavorable cancer. In the entire cohort, 221 of 1,630 (13.6 %) total patients had pathologically favorable cancer. Among 332 patients with TTV data available, 26 (7.8 %) had classically defined pathologically insignificant cancer. Between threshold probabilities of 20 and 40 %, decision curve analysis demonstrated that using multivariable model to identify AS candidates would not provide any benefit over simply treating all men who have intermediate-risk disease with RP. Although a minority of patients with intermediate-risk disease may harbor pathologically favorable or insignificant cancer, currently available conventional tools are not sufficiently able to identify those patients.

Multifragmentation in intermediate energy heavy ion collisions

International Nuclear Information System (INIS)

Jacak, B.V.; Britt, H.C.; Claesson, G.

1986-01-01

There has been considerable recent interest in the production of intermediate mass fragments (A > 4) in intermediate and high energy nucleus-nucleus collisions. The mechanism for production of these fragments is not well understood and has been described by models employing a variety of assumptions. Some examples are: disassembly of a system in thermal equilibrium into nucleons and nuclear fragments, liquid-vapor phase transitions in nuclear matter, final state coalescence of nucleons and dynamical correlations between nucleons at breakup. Previous studies of fragment production, with one exception, have been single particle inclusive measurements; the observed fragment mass (or charge) distributions can be described by all of the models above. To gain insight into the fragment production mechanism, the authors used the GSI/LBL Plastic Ball detector system to get full azimuthal coverage for intermediate mass fragments in the forward hemisphere in the center of mass system while measuring all the light particles in each event. The authors studied the systems 200 MeV/nucleon Au + Au and Au + Fe

Intermediate-energy neutron beam for NCT at MURR

International Nuclear Information System (INIS)

Brugger, R.M.; Less, T.J.; Passmore, G.G.

1986-01-01

The University of Missouri Research Reactor (MURR) is one of the high-flux reactors in the USA and it can be used to produce an intense beam of intermediate-energy neutrons for neutron capture therapy. Two methods are being evaluated at MURR to produce such a beam. The first uses a moderator of Al 2 O 3 replacing part of the graphite and water on one side of the core of the reactor to produce a source of predominantly intermediate-energy neutrons. The second method is a filter of 238 U between the core and the patient position to pass only intermediate-energy neutrons. The results of these evaluations are presented in this paper along with an outline of the other resources at the University of Missouri-Columbia that are available to support an NCT program. 4 references, 7 figures, 1 table

An African grassland responds similarly to long-term fertilization to the Park Grass experiment.

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David Ward

Full Text Available We compared the results of a long-term (65 years experiment in a South African grassland with the world's longest-running ecological experiment, the Park Grass study at Rothamsted, U.K. The climate is warm and humid in South Africa and cool and temperate in England. The African grassland has been fertilized with two forms of nitrogen applied at four levels, phosphorus and lime in a crossed design in 96 plots. In 1951, about 84% of plant cover consisted of Themeda triandra, Tristachya leucothrix and Setaria nigrirostris. Currently, the dominant species are Panicum maximum, Setaria sphacelata and Eragrostis curvula, making up 71% of total biomass. As in the Park Grass experiment, we found a significant (additive interaction effect on ANPP of nitrogen and phosphorus, and a (marginally significant negative correlation between ANPP and species richness. Unlike the Park Grass experiment, there was no correlation between ANPP and species richness when pH was included as a covariate. There was also a significant negative effect of nitrogen amount and nitrogen form and a positive effect of lime on species richness and species diversity. Soil pH had an important effect on species richness. Liming was insufficient to balance the negative effects on species richness of nitrogen fertilization. There was a significant effect of pH on biomass of three abundant species. There were also significant effects of light on the biomass of four species, with only Panicum maximum having a negative response to light. In all of the abundant species, adding total species richness and ANPP to the model increased the amount of variance explained. The biomass of Eragrostis curvula and P. maximum were negatively correlated with species richness while three other abundant species increased with species richness, suggesting that competition and facilitation were active. Consistent with the results from the Park Grass and other long-term fertilization experiments of grasslands

The geographical distribution and habitats of three liver fluke intermediate hosts in South - Africa and the health implications involved

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K. N. de Kock

2008-09-01

described as permanent, standing, fresh and clear. Although the highest percentage of samples of all three species was reported from loci that fell within the interval ranging from 16-20°C, a significant number of samples of L. truncatula came from loci falling with in the 11-15°C interval. In view of the fact that Lymnaea species are well known as intermediate hosts for liver fluke in South Africa and elsewhere in the world, the widespread occurrence of these snails could have considerable health and economic consequences. Lymnaea natalenis is the most important and probably the only intermediate host of Fasciola gigantica, the most common liver fluke in Africa but F. gigantica has been reliably reported only from Lesotho where its traditional intermediate host, L. truncatula is widespread. However, the epidemiology of fasciolosis in South Africa has been complicated by the invasion of many water-bodies by L. columella because this species has proved to be a successful host for F. hepatica where it had been introduced elsewhere in the world. To our knowledge its role in South Africa in this respect has not yet been evaluated. Due to the fact that no statistics are available in print, the results of positive serological tests on cattle herds all over South Africa were used to compile a map depicting the possible occurrence of Fasciola species in livestock in this country. Although human infections with Fasciola in Africa was considered as very rare in 1975 the situation has changed. It is considered an underrated and underreported disease in humans in Ethiopia and in Egypt an increase in cases of fasciolosis and prevalence’s as high as 12.8% in humans have also recently been reported. To our knowledge the only cases of human fasciolosis reported in literature for South Africa were from northern KwaZulu-Natal where F. hepatica infections were found in 22 out of 7 569 school children examined in 1981. Efforts to obtain recent statisticson human infections from various

Thermogravimetric control of intermediate compounds in uranium metallurgy

International Nuclear Information System (INIS)

Gasco Sanchez, L.; Fernandez Cellini, R.

1959-01-01

The thermal decomposition of some intermediate compounds in the metallurgy of the uranium as uranium peroxide, ammonium uranate, uranium and ammonium penta-fluoride, uranium tetrafluoride and uranous oxide has been study by means of the Chevenard's thermo balance. Some data on pyrolysis of synthetic mixtures of intermediate compounds which may occasionally appear during the industrial process, are given. Thermogravimetric methods of control are suggested, usable in interesting products in the uranium metallurgy. (Author) 20 refs

Intermediate-energy neutron beams from reactors for NCT

International Nuclear Information System (INIS)

Brugger, R.M.; Less, T.J.; Passmore, G.G.

1986-01-01

This paper discusses ways that a beam of intermediate-energy neutrons might be extracted from a nuclear reactor. The challenge is to suppress the fast-neutron component and the gamma-ray component of the flux while leaving enough of the intermediate-energy neutrons in the beam to be able to perform neutron capture therapy in less than an hour exposure time. Moderators, filters, and reflectors are considered. 11 references, 7 figures, 3 tables

Larval helminths in intermediate hosts

DEFF Research Database (Denmark)

Fredensborg, Brian Lund; Poulin, R

2005-01-01

Density-dependent effects on parasite fitness have been documented from adult helminths in their definitive hosts. There have, however, been no studies on the cost of sharing an intermediate host with other parasites in terms of reduced adult parasite fecundity. Even if larval parasites suffer a ...

Intermediate/Advanced Research Design and Statistics

Science.gov (United States)

Ploutz-Snyder, Robert

2009-01-01

The purpose of this module is To provide Institutional Researchers (IRs) with an understanding of the principles of advanced research design and the intermediate/advanced statistical procedures consistent with such designs

Synthesized TiO{sub 2}/ZSM-5 composites used for the photocatalytic degradation of azo dye: Intermediates, reaction pathway, mechanism and bio-toxicity

Energy Technology Data Exchange (ETDEWEB)

Zhou, Kefu; Hu, Xin-Yan [College of the Environment and Ecology, Xiamen University, Xiamen (China); Chen, Bor-Yann; Hsueh, Chung-Chuan [Department of Chemical and Materials Engineering, National I-Lan University, I-Lan, Taiwan (China); Zhang, Qian [Department of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China); Wang, Jiajie; Lin, Yu-Jung [College of the Environment and Ecology, Xiamen University, Xiamen (China); Chang, Chang-Tang, E-mail: ctchang73222@gmail.com [Department of Environmental Engineering, National I-Lan University, I-Lan, Taiwan (China)

2016-10-15

Highlights: • The major photo-catalytic degradation pathway of azo-dye was elaborated according to the identification of by-products from GC–MS and IC analysis. • Comparative assessment on characteristics of abiotic and biotic dye decolorization was analyzed. • EDTA (hole scavengers) and t-BuOH (radical scavengers) were used to determine the main active oxidative species in the system. • The toxicity effects of degradation intermediates of Reactive Black 5 (RB5) on the cellular respiratory activity were assessed. - Abstract: In this study, a one-step solid dispersion method was used to synthesize titanium dioxide (TiO{sub 2})/Zeolite Socony Mobil-5 (ZSM-5) composites with substantially reduced time and energy consumption. A degradation efficiency of more than 95% was achieved within 10 min using 50% PTZ (synthesized TiO{sub 2}/ZSM-5 composites with TiO{sub 2} contents of 50 wt% loaded on ZSM-5) at pH 7 and 25 °C. The possible degradation pathway of azo-dye Reactive Black 5 (RB5) was investigated using gas chromatography–mass spectrometry and ion chromatography (IC). The bonds between the N atoms and naphthalene groups are likely attacked first and cleaved by hydroxyl radicals, ultimately resulting in the decolorization and mineralization of the azo dye. A comparative assessment of the characteristics of abiotic and biotic dye decolorization was completed. In addition, the toxicity effects of the degradation intermediates of azo-dye RB5 on cellular respiratory activity were analyzed. The bio-toxicity results showed that the decay rate constants of CO{sub 2} production from the azo-dye RB5 samples at different degradation times increased initially and subsequently decreased, indicating that intermediates of higher toxicity could adhere to the catalyst surface and gradually destroyed by further photocatalytic oxidation. Additionally, EDTA (hole scavengers) and t-BuOH (radical scavengers) were used to detect the main active oxidative species in the system

Thin-film intermediate band chalcopyrite solar cells

International Nuclear Information System (INIS)

Fuertes Marron, D.; Marti, A.; Luque, A.

2009-01-01

Chalcopyrite-based solar cells currently lead the efficiency tables of thin-film photovoltaic technologies. Further improvements are foreseen upon implementation of an intermediate band in the absorber layers. We present a theoretical analysis of the efficiency limit for this type of device as a function of factors such as the gap of the host, the relative position of the intermediate band with respect to the band edge and the level of light concentration used as illumination. We have also considered the impact of non-idealities on the performance of the device, particularly the effect of electronic losses related to non-radiative recombination

Conditioning of intermediate-level waste at Forschungszentrum Juelich GmbH

International Nuclear Information System (INIS)

Krumbach, H.

2003-01-01

This contribution to the group of low-level, intermediate, mixed and hazardous waste describes the conditioning of intermediate-level mixed waste (dose rate above 10 mSv/h at the surface) from Research Centre Juelich (FZJ). Conditioning of the waste by supercompaction is performed at Research Centre Karlsruhe (FZK). The waste described is radioactive waste arising from research at Juelich. This waste includes specimens and objects from irradiation experiments in the research reactors Merlin (FRJ-1) and Dido (FRJ-2) at FZJ. In principle, radioactive waste at Forschungszentrum Juelich GmbH is differentiated by the surface dose rate at the waste package. Up to a surface dose rate of 10 mSv/h, the waste is regarded as low-level. The radioactive waste described here has a surface dose rate above 10 mSv/h. Waste up to 10 mSv/h is conditioned at the Juelich site according to different conditioning methods. The intermediate-level waste can only be conditioned by supercompaction in the processing facility for intermediate-level waste from plant operation at Research Centre Karlsruhe. Research Centre Juelich also uses this waste cell to condition its intermediate-level waste from plant operation. (orig.)

Intermediate Filaments at the Junction of Mechanotransduction, Migration, and Development

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Rucha Sanghvi-Shah

2017-09-01

Full Text Available Mechanically induced signal transduction has an essential role in development. Cells actively transduce and respond to mechanical signals and their internal architecture must manage the associated forces while also being dynamically responsive. With unique assembly-disassembly dynamics and physical properties, cytoplasmic intermediate filaments play an important role in regulating cell shape and mechanical integrity. While this function has been recognized and appreciated for more than 30 years, continually emerging data also demonstrate important roles of intermediate filaments in cell signal transduction. In this review, with a particular focus on keratins and vimentin, the relationship between the physical state of intermediate filaments and their role in mechanotransduction signaling is illustrated through a survey of current literature. Association with adhesion receptors such as cadherins and integrins provides a critical interface through which intermediate filaments are exposed to forces from a cell's environment. As a consequence, these cytoskeletal networks are posttranslationally modified, remodeled and reorganized with direct impacts on local signal transduction events and cell migratory behaviors important to development. We propose that intermediate filaments provide an opportune platform for cells to both cope with mechanical forces and modulate signal transduction.

Singlet channel coupling in deuteron elastic scattering at intermediate energies

International Nuclear Information System (INIS)

Al-Khalili, J.S.; Tostevin, J.A.; Johnson, R.C.

1990-01-01

Intermediate energy deuteron elastic scattering is investigated in a three-body model incorporating relativistic kinematics. The effects of deuteron breakup to singlet spin intermediate states, on the elastic scattering observables for the 58 Ni(d vector, d) 58 Ni reaction at 400 and 700 MeV, are studied quantitatively. The singlet-breakup contributions to the elastic amplitude are estimated within an approximate two-step calculation. The calculation makes an adiabatic approximation in the intermediate states propagator which allows the use of closure over the np intermediate states continuum. The singlet channel coupling is found to produce large effects on the calculated reaction tensor analysing power A yy , characteristic of a dynamically induced second-rank tensor interaction. By inspection of the calculated breakup amplitudes we show this induced interaction to be of the T L tensor type. (orig.)

Growth Responses of Three Dominant Wetland Plant Species to Various Flooding and Nutrient Levels

Science.gov (United States)

Barrett, S.; Shaffer, G. P.

2017-12-01

Coastal Louisiana is experiencing a greater rate of wetland loss than any other wetland system in the United States. This is primarily due to anthropogenic stressors such as flood control levees, backfilling and development of wetlands, and other hydrologic modifications. Methods employed to mitigate wetland loss include the construction of river diversions and assimilation wetlands, which can provide consistent sources of freshwater influx and nutrients to impounded swamps and marshes. It is well known that prolonged flooding causes strain on wetland plant communities and facilitates or exacerbates wetland degradation. However, because river diversions and assimilation wetlands bring high nutrient loads along with freshwater, there is debate over whether prolonged flooding or high influx of nutrients is the primary cause of stress in river diversion and assimilation wetland discharge areas. This mesocosm experiment addresses this question by isolating the effects of flooding and nutrients on the biomass of baldcypress (Taxodium distichum), maidencane (Panicum hemitomon), and cordgrass (Spartina patens) over the course of a growing season. The results of this study provide clarity as to whether flooding stress, high nutrient loads, or both cause a reduction in wetland plant productivity. By evaluating the growth responses of T. distichum, P. hemitomon, and S. patens at varying nutrient regimes, we gain insight on how these more dominant species will react to high nutrient discharges from large river diversions, such as those proposed in Louisiana's 2017 Master Plan.

"Affective Encounters": Live Intermedial Spaces in Sites of Trauma

Science.gov (United States)

Scott, Jo

2016-01-01

This article addresses live intermediality as a tool for creative learning in the context of workshops carried out with young people in the town of Terezin, in the Czech Republic, site of the Nazi concentration camp, Theresienstadt. Live intermediality, as a mode of live media practice, involves the real time mixing and merging of sound, image,…

Ecological niche transferability using invasive species as a case study.

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Miguel Fernández

Full Text Available Species distribution modeling is widely applied to predict invasive species distributions and species range shifts under climate change. Accurate predictions depend upon meeting the assumption that ecological niches are conserved, i.e., spatially or temporally transferable. Here we present a multi-taxon comparative analysis of niche conservatism using biological invasion events well documented in natural history museum collections. Our goal is to assess spatial transferability of the climatic niche of a range of noxious terrestrial invasive species using two complementary approaches. First we compare species' native versus invasive ranges in environmental space using two distinct methods, Principal Components Analysis and Mahalanobis distance. Second we compare species' native versus invaded ranges in geographic space as estimated using the species distribution modeling technique Maxent and the comparative index Hellinger's I. We find that species exhibit a range of responses, from almost complete transferability, in which the invaded niches completely overlap with the native niches, to a complete dissociation between native and invaded ranges. Intermediate responses included expansion of dimension attributable to either temperature or precipitation derived variables, as well as niche expansion in multiple dimensions. We conclude that the ecological niche in the native range is generally a poor predictor of invaded range and, by analogy, the ecological niche may be a poor predictor of range shifts under climate change. We suggest that assessing dimensions of niche transferability prior to standard species distribution modeling may improve the understanding of species' dynamics in the invaded range.

Oxidative demethylation of lanosterol in cholesterol biosynthesis: accumulation of sterol intermediates

International Nuclear Information System (INIS)

Shafiee, A.; Trzaskos, J.M.; Paik, Y.K.; Gaylor, J.L.

1986-01-01

With [ 3 H-24,25]-dihydrolanosterol as substrate, large-scale metabolic formation of intermediates of lanosterol demethylation was carried out to identify all compounds in the metabolic process. Utilizing knowledge of electron transport of lanosterol demethylation, we interrupted the demethylation reaction allowing accumulation and confirmation of the structure of the oxygenated intermediates lanost-8-en-3 beta,32-diol and 3 beta-hydroxylanost-8-en-32-al, as well as the demethylation product 4,4-dimethyl-cholesta-8,14-dien-3 beta-ol. Further metabolism of the delta 8.14-diene intermediate to a single product 4,4-dimethyl-cholest-8-en-3 beta-ol occurs under interruption conditions in the presence of 0.5 mM CN-1. With authentic compounds, each intermediate has been rigorously characterized by high performance liquid chromatography and gas-liquid chromatography plus mass spectral analysis of isolated and derivatized sterols. Intermediates that accumulated in greater abundance were further characterized by ultraviolet, 1 H-NMR, and infrared spectroscopy of the isolated sterols

About the investigation of the ultrasonic absorption in intermediate states of superconductors

International Nuclear Information System (INIS)

Shepelev, A.G.

2003-01-01

Investigation of intermediate state in the bulk of superconductors are surveyed. Consideration is given to a previous attempt of eliminating edge effects in the ultrasonic investigation of intermediate states of pure gallium and molybdenum;it is demonstrated that those results are in strong contradiction with Landau's intermediate-state theory

Corrosion susceptibility of steel drums to be used as containers for intermediate level nuclear waste

International Nuclear Information System (INIS)

Farina, S.; Schulz Rodriguez, F.; Duffo, G.

2013-01-01

The present work is a study of the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins contaminated with different types and concentrations of aggressive species. A special type of specimen was manufactured to simulate the cemented ion-exchange resins in the drum. The evolution of the corrosion potential and the corrosion rate of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 900 days. The aggressive species studied were chloride ions (the main ionic species of concern) and sulphate ions (produced during radiolysis of the cationic exchange-resins after cementation). The work was complemented with an analysis of the corrosion products formed on the steel in each condition, as well as the morphology of the corrosion products. When applying the results obtained in the present work to estimate the corrosion depth of the steel drums containing the cemented radioactive waste after a period of 300 years (foreseen durability of the Intermediate Level Radioactive Waste facility in Argentina), it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. (authors)

Identification of combustion intermediates in low-pressure premixed pyridine/oxygen/argon flames.

Science.gov (United States)

Tian, Zhenyu; Li, Yuyang; Zhang, Taichang; Zhu, Aiguo; Qi, Fei

2008-12-25

Combustion intermediates of two low-pressure premixed pyridine/oxygen flames with respective equivalence ratios of 0.56 (C/O/N = 1:4.83:0.20) and 2.10 (C/O/N = 1:1.29:0.20) have been identified with tunable synchrotron vacuum ultraviolet (VUV) photoionization and molecular-beam mass spectrometry techniques. About 80 intermediates in the rich flame and 60 intermediates in the lean flame, including nitrogenous, oxygenated, and hydrocarbon intermediates, have been identified by measurements of photoionization mass spectra and photoionization efficiency spectra. Some radicals and new nitrogenous intermediates are identified in the present work. The experimental results are useful for studying the conversion of volatile nitrogen compounds and understanding the formation mechanism of NO(x) in flames of nitrogenous fuels.

A new species of the genus Alterosa (Trichoptera: Philopotaminae from Southeastern Brazil

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Gabriela Abrantes Jardim

2012-06-01

Full Text Available Philopotamidae is a large caddisfly family with 20 extant genera comprising about 1 000 described species worldwide. Alterosa contains 22 described species distributed in South and Southeastern Brazil. Adults of the genus are very similar in general structure, but are remarkable for their wide variation in male genitalic morphology. The specimens were collected with Pennsylvania light traps and preserved in 80% ethanol. Alterosa nessimiani sp. nov. is described and figured from male specimens collected in streams of Rio de Janeiro state, Southeastern Brazil. The new species is closely related to A. jordaensis Blahnik 2005, from which it can be distinguished by the presence of two spines on the intermediate appendages and by the shape of tergum X. Rev. Biol. Trop. 60 (2: 577-580. Epub 2012 June 01.

Wide-band tracheids are present in almost all species of Cactaceae.

Science.gov (United States)

Mauseth, James D

2004-02-01

Wide-band tracheids (WBTs) have been found in seedlings of most species of cacti that have fibrous wood in their adult bodies. Consequently, this cell type is now known to be present in almost all cacti. Earlier studies of adult plants revealed WBTs to be present only in cacti with globose or short, broad bodies, whereas all species with large columnar or long slender bodies had fibrous wood without WBTs. However, even these species produce WBTs during the first several months after germination. In species with fibrous wood in their adult bodies (species with large or slender bodies), seedlings undergo a phase transition in wood morphogenesis after a few months and stop producing the juvenile (WBT) wood and begin producing adult (fibrous) wood. If adult plants have an intermediate size, the phase transition is delayed and the plant produces WBT wood for several years. Species with globose bodies repress the phase transition completely and never switch to producing adult (fibrous) wood. Because WBTs are so widespread, they probably originated only once in Cactaceae, not multiple times as suggested earlier, or there may have been just a single origin in the Cactaceae/Portulacaceae clade.

Hγ Line Spectrum of Intermediate Polars

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Yonggi Kim

1998-06-01

Full Text Available Kim & Beuermann (1995, 1996 have developed a model for the propagation of X-rays from the accreting white dwarf through the infalling material and the re-emission of the energy deposited by photo-absorption in the optical (and UV spectral range. By using this model, we calculate the profiles of the Hγ emission-line spectrum of intermediate polars. Photoabsorption of X-rays by the infalling material is the dominant process in forming the observed energy-dependent rotational modulation of the X-ray flux. X-ray and optical modulations are sensitive to model parameters in different ways. In principle, these dependencies allow us to obtain improved insight into the accretion geometry of the intermediate polars. We present results of our calculations and compare them with the Hβ line spectrum (Kim & Beuermann 1996.

DIVERSITY SURFACES AND SPECIES WAVE FRONTS IN A SOIL MICROARTHROPOD ASSEMBLAGE: ADDING THE DIMENSION OF TIME

Science.gov (United States)

As a general rule, animal species of intermediate size within a given taxonomic group are most abundant in nature. It is not known if these patterns occur in small-bodied taxa, such as soil microarthropods, or how these patterns change through time. Here I show that Oribatida (Ac...

Effects of natural phenomena and human activity on the species richness of endemic and non-endemic Heteroptera in the Canary Islands

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Vargas, J. M.

2004-12-01

Full Text Available The geographical patterns of Heteroptera species diversity in the Canary Islands were analysed, and endemic and non–endemic species were studied both together and separately. Causal processes most likely controlling these patterns, as well as the theory of island biogeography, hypotheses about evolutionary time, habitat heterogeneity, climatic stability, intermediate disturbances, energy, environmental favourableness–severity, productivity and human influence were investigated. The combination of habitat heterogeneity and human influence accounted for the total number of species. However, when endemic and non–endemic species were analysed separately, habitat heterogeneity and favourableness–severity explained the richness of endemic species, whereas habitat heterogeneity and human influence explained that of non–endemic species.

In search of critically endangered species: the current situation of two tiny salamander species in the Neotropical mountains of Mexico.

Science.gov (United States)

Sandoval-Comte, Adriana; Pineda, Eduardo; Aguilar-López, José L

2012-01-01

Worldwide, one in every three species of amphibian is endangered, 39 species have gone extinct in the last 500 years and another 130 species are suspected to have gone extinct in recent decades. Of the amphibians, salamanders have the highest portion of their species in one of the risk categories, even higher than the frogs. To date there have been few studies that have used recent field data to examine the status of populations of endangered salamanders. In this study we evaluate the current situation of two tiny salamanders, Parvimolge townsendi and Thorius pennatulus, both of which are distributed at intermediate elevations in the mountains of the northern Neotropics and are considered to be critically endangered; the first has been proposed as possibly extinct. By carrying out exhaustive surveys in both historical and potentially suitable sites for these two species, we evaluated their abundance and the characteristics of their habitats, and we estimated their potential geographic distribution. We visited 22 sites, investing 672 person-hours of sampling effort in the surveys, and found 201 P. townsendi salamanders in 11 sites and only 13 T. pennatulus salamanders in 5 sites. Both species were preferentially found in cloud forest fragments that were well conserved or only moderately transformed, and some of the salamanders were found in shade coffee plantations. The potential distribution area of both species is markedly fragmented and we estimate that it has decreased by more than 48%. The results of this study highlight the importance of carrying out exhaustive, systematic field surveys to obtain accurate information about the current situation of critically endangered species, and help us better understand the crisis that amphibians are facing worldwide.

Nuclear spin-orbit splitting from an intermediate Δ excitation

International Nuclear Information System (INIS)

Ohta, K.; Terasawa, T.; Tohyama, M.

1980-01-01

The strength of the single particle spin-orbit potential is calculated from the two pion exchange box diagrams involving an intermediate Δ(1232) resonance excitation by taking account of the exclusion principle for the intermediate nucleon states. The effect of the rho meson is also considered. The predicted strength is found to account for a substantial part of the empirical spin-orbit splittings

42 CFR 422.750 - Types of intermediate sanctions and civil money penalties.

Science.gov (United States)

2010-10-01

... 42 Public Health 3 2010-10-01 2010-10-01 false Types of intermediate sanctions and civil money... § 422.750 Types of intermediate sanctions and civil money penalties. (a) The following intermediate... organization. (b) CMS may impose civil money penalties as specified in 422.760. [72 FR 68725, Dec. 5, 2007, as...

Microdosimetry of intermediate energy neutrons in fast neutron fields

International Nuclear Information System (INIS)

Saion, E.B.; Watt, D.E.

1988-01-01

A coaxial double cylindrical proportional counter has been constructed for microdosimetry of intermediate energy neutrons in mixed fields. Details are given of the measured gas gain and resolution characteristics of the counter for a wide range of anode voltages. Event spectra due to intermediate neutrons in any desired energy band is achieved by an appropriate choice of thickness of the common dividing wall in the counter and by appropriate use of the coincidence, anticoincidence pulse counting arrangements. Calculated estimates indicate that the dose contribution by fast neutrons to the energy deposition events in the intermediate neutron range may be as large as 25%. Empirical procedures being investigated aim to determine the necessary corrections to be applied to the microdose distributions, with a precision of 10%. (author)

About the structure of quantum intermediate state of superconductors

International Nuclear Information System (INIS)

Ledenev, O.P.

2008-01-01

The calculation of spatial structure of a quantum intermediate state in Type I superconductors is completed. Theoretical model of thermodynamics of considered state was proposed by Andreev. It is shown, that in a quantum case, the period of structure appears significantly smaller and has different dependence on both the magnetic field and temperature than in the classical intermediate Landau state. The decrease of thickness of normal layers results in increase of characteristic distance between the quantum Andreev levels of electronic excitations, and the transition to the quantum intermediate from classical state is realized at higher temperatures ∼1 K, than it was supposed in previous works. The comparison of calculation data with experimental results, for example using the sample of mono-crystal gallium, is conducted

Negotiating comfort in low energy housing: The politics of intermediation

International Nuclear Information System (INIS)

Grandclément, Catherine; Karvonen, Andrew; Guy, Simon

2015-01-01

Optimising the energy performance of buildings is technically and economically challenging but it also has significant social implications. Maintaining comfortable indoor conditions while reducing energy consumption involves careful design, construction, and management of the built environment and its inhabitants. In this paper, we present findings from the study of a new low energy building for older people in Grenoble, France where conflicts emerged over the simultaneous pursuit of energy efficiency and comfort. The findings contribute to the contemporary literature on the sociotechnical study of buildings and energy use by focusing on intermediation, those activities that associate a technology to end users. Intermediation activities take many forms, and in some cases, can result in the harmonisation or alignment of energy efficiency goals and comfort goals. In other cases, intermediation is unsuccessful, leading to the conventional dichotomy between optimising technical performance and meeting occupant preferences. By highlighting the multiple ways that comfort and energy efficiency is negotiated, we conclude that buildings are provisional achievements that are constantly being intermediated. This suggests that building energy efficiency policies and programmes need to provide opportunities for intermediaries to negotiate the desires and preferences of the multiple stakeholders that are implicated in low energy buildings. -- Highlights: •Energy efficiency and comfort are two possibly contradictory aims of buildings. •We study the pursuit of these aims at the occupation stage of a new building. •Aligning these aims involve negotiating them with occupants. •Intermediation processes are key to such negotiations. •Intermediation processes involve both actors and technical devices

Deep and intermediate mediterranean water in the western Alboran Sea

Science.gov (United States)

Parrilla, Gregorio; Kinder, Thomas H.; Preller, Ruth H.

1986-01-01

Hydrographic and current meter data, obtained during June to October 1982, and numerical model experiments are used to study the distribution and flow of Mediterranean waters in the western Alboran Sea. The Intermediate Water is more pronounced in the northern three-fourths of the sea, but its distribution is patchy as manifested by variability of the temperature and salinity maxima at scales ≤10 km. Current meters in the lower Intermediate Water showed mean flow toward the Strait at 2 cm s -1. A reversal of this flow lasted about 2 weeks. A rough estimate of the mean westward Intermediate Water transport was 0.4 × 10 6 m 3 s -1, about one-third of the total outflow, so that the best estimates of the contributions of traditionally defined Intermediate Water and Deep Water account for only about one-half of the total outflow. The Deep Water was uplifted against the southern continental slope from Alboran Island (3°W) to the Strait. There was also a similar but much weaker banking against the Spanish slope, but a deep current record showed that the eastward recirculation implied by this banking is probably intermittent. Two-layer numerical model experiments simulated the Intermediate Water flow with a flat bottom and the Deep Water with realistic bottom topography. Both experiments replicated the major circulation features, and the Intermediate Water flow was concentrated in the north because of rotation and the Deep Water flow in the south because of topographic control.

Legumes and forage species sole or intercropped with corn in soybean-corn succession in midwestern Brazil

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Gessí Ceccon

2013-02-01

Full Text Available The feasibility of no-tillage in the Cerrado (Savanna-like vegetation of Brazil depends on the production of sufficient above-ground crop residue, which can be increased by corn-forage intercropping. This study evaluated how above-ground crop residue production and yields of soybean and late-season corn in a soybean-corn rotation were influenced by the following crops in the year before soybean: corn (Zea mays L. intercropped with Brachiaria (Urochloa brizantha cv. Marandu, B. decumbens cv. Basilisk, B. ruziziensis, cv. comum., Panicummaximum cv. Tanzânia, sunn hemp (Crotalaria juncea L., pigeon pea [Cajanus cajan (L. Millsp]; sole corn, forage sorghum [Sorghum bicolor (L. Moench (cv. Santa Elisa], and ruzi grass. In March 2005, corn and forage species were planted in alternate rows spaced 0.90 m apart, and sole forage species were planted in rows spaced 0.45 m apart. In October 2005, the forages were killed with glyphosate and soybean was planted. After the soybean harvest in March 2006, sole late-season corn was planted in the entire experimental area. Corn grain and stover yields were unaffected by intercropping. Above-ground crop residue was greater when corn was intercropped with Tanzania grass (10.7 Mg ha-1, Marandu (10.1 Mg ha-1, and Ruzi Grass (9.8 Mg ha-1 than when corn was not intercropped (4.0 Mg ha-1. The intercropped treatments increased the percentage of soil surface covered with crop residue. Soybean and corn grain yields were higher after sole ruzi grass and intercropped ruzi grass than after other crops. The intercropping corn with Brachiaria spp. and corn with Panicum spp. increases above-ground crop residue production and maintains nutrients in the soil without reducing late-season corn yield and the viability of no-till in the midwestern region of Brazil.

A hybrid intermediate language between SSA and CPS

DEFF Research Database (Denmark)

Torrens, Paulo; Vasconcellos, Cristiano; Gonçalves, Ju

2017-01-01

passing style (CPS) lambda calculus has been used as intermediate language for functional language compilers, they are (almost) equivalent and it is possible to draw syntactic translations between them. This short paper aims to present an untyped intermediate language which may be interpreted as both SSA...... and CPS, in order to provide a common language for both imperative and functional compilers, as well to take advantage of optimizations designed for either one of the approaches. Finally, potential variants and research opportunities are discussed....

Intermediate states in quantum cryptography and Bell inequalities

International Nuclear Information System (INIS)

Bechmann-Pasquinucci, H.; Gisin, N.

2003-01-01

Intermediate states are known from intercept/resend eavesdropping in the Bennett-Brassard 1984 (BB84) quantum cryptographic protocol. But they also play fundamental roles in the optimal eavesdropping strategy on the BB84 protocol and in the CHSH (Clauser-Horne-Shimony-Holt) inequality. We generalize the intermediate states to an arbitrary dimension and consider intercept/resend eavesdropping, optimal eavesdropping on the generalized BB84 protocol and present a generalized Clauser-Horne-Shimony-Holt inequality for two entangled qudits based on these states

Reactivity of Criegee Intermediates toward Carbon Dioxide.

Science.gov (United States)

Lin, Yen-Hsiu; Takahashi, Kaito; Lin, Jim Jr-Min

2018-01-04

Recent theoretical work by Kumar and Francisco suggested that the high reactivity of Criegee intermediates (CIs) could be utilized for designing efficient carbon capture technologies. Because the anti-CH 3 CHOO + CO 2 reaction has the lowest barrier in their study, we chose to investigate it experimentally. We probed anti-CH 3 CHOO with its strong UV absorption at 365 nm and measured the rate coefficient to be ≤2 × 10 -17 cm 3 molecule -1 s -1 at 298 K, which is consistent with our theoretical value of 2.1 × 10 -17 cm 3  molecule -1 s -1 at the QCISD(T)/CBS//B3LYP/6-311+G(2d,2p) level but inconsistent with their results obtained at the M06-2X/aug-cc-pVTZ level, which tends to underestimate the barrier heights. The experimental result indicates that the reaction of a Criegee intermediate with atmospheric CO 2 (400 ppmv) would be inefficient (k eff < 0.2 s -1 ) and cannot compete with other decay processes of Criegee intermediates like reactions with water vapor (∼10 3 s -1 ) or thermal decomposition (∼10 2 s -1 ).

Intermediate-range order in lead metasilicate glass

Energy Technology Data Exchange (ETDEWEB)

Suzuya, Kentaro [Japan Atomic Energy Research Inst., Ako, Hyogo (Japan)]|[Argonne National Lab., IL (United States). Materials Science Div.; Price, D.L.; Saboungi, M.L. [Argonne National Lab., IL (United States). Materials Science Div.; Ohno, Hideo [Japan Atomic Energy Research Inst., Ako, Hyogo (Japan)

1997-03-01

The complementarity of anomalous X-ray scattering (AXS) and neutron diffraction (ND) techniques is used here to investigate the nature and origin of intermediate-range order in lead metasilicate glass. Both X-ray and neutron source factors reveal small peaks at low wave vector which are shown to be associated with intermediate-range order of the Pb-O network. The combination of AXS and ND is shown to be a powerful tool to correlate contributions from the different atom pairs to such a peak. The information thus derived is compared with results from alkali germanate glasses and with structural data on corresponding crystalline compounds.

Low temperature intermediate band metallic behavior in Ti implanted Si

Energy Technology Data Exchange (ETDEWEB)

Olea, Javier, E-mail: oleaariza@fis.ucm.es; Pastor, David; Garcia-Hemme, Eric; Garcia-Hernansanz, Rodrigo; Prado, Alvaro del; Martil, Ignacio; Gonzalez-Diaz, German

2012-08-31

Si samples implanted with very high Ti doses and subjected to Pulsed-Laser Melting (PLM) have been electrically analyzed in the scope of a two-layer model previously reported based on the Intermediate Band (IB) theory. Conductivity and Hall effect measurements using the van der Pauw technique suggest that the insulator-metal transition takes place for implantation doses in the 10{sup 14}-10{sup 16} cm{sup -2} range. Results of the sample implanted with the 10{sup 16} cm{sup -2} dose show a metallic behavior at low temperature that is explained by the formation of a p-type IB out of the Ti deep levels. This suggests that the IB would be semi-filled, which is essential for IB photovoltaic devices. - Highlights: Black-Right-Pointing-Pointer We fabricated high dose Ti implanted Si samples for intermediate band research. Black-Right-Pointing-Pointer We measured the electronic transport properties in the 7-300 K range. Black-Right-Pointing-Pointer We show an insulator to metallic transition when the intermediate band is formed. Black-Right-Pointing-Pointer The intermediate band is semi-filled and populated by holes. Black-Right-Pointing-Pointer We satisfactorily explain the electrical behavior by an intermediate band model.

Intermediate organizations in the innovation process in Mexico

Directory of Open Access Journals (Sweden)

Maria del Pilar Monserrat Pérez Hernández

2016-07-01

Full Text Available The innovation activity depends strongly on the interaction between generating actors and end-users of new knowledge and technologies. There are several intermediate organizations (IO that facilitate translating the needs of the users with the new technologies that are beingdeveloped, in order to satisfy more effectively their demands. This paper analyzes the mediation process involved in the IO in innovative activity in Mexico, to identify structural holes in the innovation process. The relevant results in the Mexican intermediation process points that threeimportant structural holes of the process are missing: one between the negotiation process and sponsorship, the second in marketing and commercial profit of the obtained results and the last one in the regulation and referring activities. It is very important that the detected missinglinks in the intermediation process are filled, because they can hinder considerably the overall profit and benefits that society could obtained of the innovation process.

Are species photosynthetic characteristics good predictors of seedling post-hurricane demographic patterns and species spatiotemporal distribution in a hurricane impacted wet montane forest?

Science.gov (United States)

Luke, Denneko; McLaren, Kurt

2018-05-01

In situ measurements of leaf level photosynthetic response to light were collected from seedlings of ten tree species from a tropical montane wet forest, the John Crow Mountains, Jamaica. A model-based recursive partitioning ('mob') algorithm was then used to identify species associations based on their fitted photosynthetic response curves. Leaf area dark respiration (RD) and light saturated maximum photosynthetic (Amax) rates were also used as 'mob' partitioning variables, to identify species associations based on seedling demographic patterns (from June 2007 to May 2010) following a hurricane (Aug. 2007) and the spatiotemporal distribution patterns of stems in 2006 and 2012. RD and Amax rates ranged from 1.14 to 2.02 μmol (CO2) m-2s-1 and 2.97-5.87 μmol (CO2) m-2s-1, respectively, placing the ten species in the range of intermediate shade tolerance. Several parsimonious species 'mob' groups were formed based on 1) interspecific differences among species response curves, 2) variations in post-hurricane seedling demographic trends and 3) RD rates and species spatiotemporal distribution patterns at aspects that are more or less exposed to hurricanes. The composition of parsimonious groupings based on photosynthetic curves was not concordant with the groups based on demographic trends but was partially concordant with the RD - species spatiotemporal distribution groups. Our results indicated that the influence of photosynthetic characteristics on demographic traits and species distributions was not straightforward. Rather, there was a complex pattern of interaction between ecophysiological and demographic traits, which determined species successional status, post-hurricane response and ultimately, species distribution at our study site.

Productivity and agronomics characteristics of Panicum maximum and Brachiária brizanta cultured in two of soil class of Tocantins state (Oxisol and Entsoil, conditioned in different water supply. Desenvolvimento e produtividade dos capins mombaça e marandu cultivadas em dois solos típicos do Tocantins com diferentes regimes hídricos

Directory of Open Access Journals (Sweden)

Jeane Alves de Almeida

2009-12-01

Full Text Available The objective of this study was to evaluate the productive and agronomic parameters of Panicum maximum cv. Mombaça and the Brachiária brizanta cv. Marandú grown in Oxisoil, and Entsoil under different water schemes. The experiment was conducted in a greenhouse in EMVZ - School of Veterinary Medicine and Zootecnia / Federal University of Tocantins, campus of Araguaína, TO. The completely randomized design in a factorial arrangement (2x4x2, which consisted of two forage species, four levels of water (25%, 50%, 75% and 100% of the capacity of field, two types of soils, with four repetitions, making 62 experimental units. The production of dry mass of Forage (MSF was linear behavior increasing in line with the increase in the percentage of moisture, for the two cultivars in two production cycles, the two types of soil, being that the clay soil in both cultivars returned relative superiority in comparison with the sandy soil. The mean width of leaves are not differentiated (P>0.05 in three major schemes in two cultivars. The same is observed for size of leaves to Mombaça grass, and for the two major Marandú. There was no (P> 0.05 for comparing stem diameter of the largest schemes. In the measures of time it was observed that plants were higher humidity in two largest (P<0.05. To the greatest number of tillers were higher humidity and is differentiated (P <0.05, while the Mombaça had many in first round. The biggest tillering in both genders occurs in water schemes not stress, and positively influence the characteristics productive, as well as in agronomic stressful when compared to schemes.O objetivo deste trabalho foi avaliar os parâmetros produtivos e agronômicos do Panicum maximum cv. Mombaça e do Brachiária brizanta cv. Marandú cultivados em Argissolo Vermelho eutroférrico, e Neossolo Quartzarênico órtico sob diferentes regimes hídricos. O experimento foi conduzido em casa de vegetação na EMVZ – Escola de Medicina Veterin

The deterioration of intermediate moisture foods

Science.gov (United States)

Labruza, T. P.

1971-01-01

Deteriorative reactions are low and food quality high if intermediate moisture content of a food is held at a water activity of 0.6 to 0.75. Information is of interest to food processing and packaging industry.

Production of intermediate-mass dileptons in relativistic heavy ion collisions

International Nuclear Information System (INIS)

Kvasnikova, Ioulia; Gale, Charles; Kumar Srivastava, Dinesh

2002-01-01

The production of intermediate-mass dileptons in ultrarelativistic nuclear collisions at SPS energies is studied. The acceptance and detector resolution inherent to measurements by the NA50 experimental collaboration are accurately modeled. The measured centrality dependence of the intermediate mass lepton pair excess is also addressed

Intermediate uveitis

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Babu B

2010-01-01

Full Text Available Intermediate uveitis (IU is described as inflammation in the anterior vitreous, ciliary body and the peripheral retina. In the Standardization of Uveitis Nomenclature (SUN working group′s international workshop for reporting clinical data the consensus reached was that the term IU should be used for that subset of uveitis where the vitreous is the major site of the inflammation and if there is an associated infection (for example, Lyme disease or systemic disease (for example, sarcoidosis. The diagnostic term pars planitis should be used only for that subset of IU where there is snow bank or snowball formation occurring in the absence of an associated infection or systemic disease (that is, "idiopathic". This article discusses the clinical features, etiology, pathogenesis, investigations and treatment of IU.

Selection and validation of reference genes for gene expression analysis in switchgrass (Panicum virgatum using quantitative real-time RT-PCR.

Directory of Open Access Journals (Sweden)

Jacinta Gimeno

Full Text Available Switchgrass (Panicum virgatum has received a lot of attention as a forage and bioenergy crop during the past few years. Gene expression studies are in progress to improve new traits and develop new cultivars. Quantitative real time PCR (qRT-PCR has emerged as an important technique to study gene expression analysis. For accurate and reliable results, normalization of data with reference genes is essential. In this work, we evaluate the stability of expression of genes to use as reference for qRT-PCR in the grass P. virgatum. Eleven candidate reference genes, including eEF-1α, UBQ6, ACT12, TUB6, eIF-4a, GAPDH, SAMDC, TUA6, CYP5, U2AF, and FTSH4, were validated for qRT-PCR normalization in different plant tissues and under different stress conditions. The expression stability of these genes was verified by the use of two distinct algorithms, geNorm and NormFinder. Differences were observed after comparison of the ranking of the candidate reference genes identified by both programs but eEF-1α, eIF-4a, CYP5 and U2AF are ranked as the most stable genes in the samples sets under study. Both programs discard the use of SAMDC and TUA6 for normalization. Validation of the reference genes proposed by geNorm and NormFinder were performed by normalization of transcript abundance of a group of target genes in different samples. Results show similar expression patterns when the best reference genes selected by both programs were used but differences were detected in the transcript abundance of the target genes. Based on the above research, we recommend the use of different statistical algorithms to identify the best reference genes for expression data normalization. The best genes selected in this study will help to improve the quality of gene expression data in a wide variety of samples in switchgrass.

File list: Unc.PSC.50.AllAg.iPSC_intermediates [Chip-atlas[Archive

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File list: Pol.PSC.10.AllAg.iPSC_intermediates [Chip-atlas[Archive

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File list: Unc.PSC.20.AllAg.iPSC_intermediates [Chip-atlas[Archive

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File list: Pol.PSC.05.AllAg.iPSC_intermediates [Chip-atlas[Archive

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Full Text Available Pol.PSC.05.AllAg.iPSC_intermediates mm9 RNA polymerase Pluripotent stem cell iPSC intermediates...e.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.05.AllAg.iPSC_intermediates.bed ...

File list: Pol.PSC.20.AllAg.iPSC_intermediates [Chip-atlas[Archive

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Full Text Available Pol.PSC.20.AllAg.iPSC_intermediates mm9 RNA polymerase Pluripotent stem cell iPSC intermediates...e.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.20.AllAg.iPSC_intermediates.bed ...

File list: Unc.PSC.10.AllAg.iPSC_intermediates [Chip-atlas[Archive

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Full Text Available Unc.PSC.10.AllAg.iPSC_intermediates mm9 Unclassified Pluripotent stem cell iPSC intermediates... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.PSC.10.AllAg.iPSC_intermediates.bed ...

File list: Pol.PSC.50.AllAg.iPSC_intermediates [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Pol.PSC.50.AllAg.iPSC_intermediates mm9 RNA polymerase Pluripotent stem cell iPSC intermediates...e.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.50.AllAg.iPSC_intermediates.bed ...

File list: Unc.PSC.05.AllAg.iPSC_intermediates [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Unc.PSC.05.AllAg.iPSC_intermediates mm9 Unclassified Pluripotent stem cell iPSC intermediates... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.PSC.05.AllAg.iPSC_intermediates.bed ...

Visual dictionaries as intermediate features in the human brain

Directory of Open Access Journals (Sweden)

Kandan eRamakrishnan

2015-01-01

Full Text Available The human visual system is assumed to transform low level visual features to object and scene representations via features of intermediate complexity. How the brain computationally represents intermediate features is still unclear. To further elucidate this, we compared the biologically plausible HMAX model and Bag of Words (BoW model from computer vision. Both these computational models use visual dictionaries, candidate features of intermediate complexity, to represent visual scenes, and the models have been proven effective in automatic object and scene recognition. These models however differ in the computation of visual dictionaries and pooling techniques. We investigated where in the brain and to what extent human fMRI responses to short video can be accounted for by multiple hierarchical levels of the HMAX and BoW models. Brain activity of 20 subjects obtained while viewing a short video clip was analyzed voxel-wise using a distance-based variation partitioning method. Results revealed that both HMAX and BoW explain a significant amount of brain activity in early visual regions V1, V2 and V3. However BoW exhibits more consistency across subjects in accounting for brain activity compared to HMAX. Furthermore, visual dictionary representations by HMAX and BoW explain significantly some brain activity in higher areas which are believed to process intermediate features. Overall our results indicate that, although both HMAX and BoW account for activity in the human visual system, the BoW seems to more faithfully represent neural responses in low and intermediate level visual areas of the brain.

Reactor-moderated intermediate-energy neutron beams for neutron-capture therapy

International Nuclear Information System (INIS)

Less, T.J.

1987-01-01

One approach to producing an intermediate energy beam is moderating fission neutrons escaping from a reactor core. The objective of this research is to evaluate materials that might produce an intermediate beam for NCT via moderation of fission neutrons. A second objective is to use the more promising moderator material in a preliminary design of an NCT facility at a research reactor. The evaluations showed that several materials or combinations of materials could produce a moderator source for an intermediate beam for NCT. The best neutron spectrum for use in NCT is produced by Al 2 O 3 , but mixtures of Al metal and D 2 O are also attractive. Using the best moderator materials, results were applied to the design of an NCT moderator at the Georgia Institute of Technology Research Reactor's bio-medical facility. The amount of photon shielding and thermal neutron absorber were optimized with respect to the desired photon dose rate and intermediate neutron flux at the patient position

Circular DNA Intermediate in the Duplication of Nile Tilapia vasa Genes

Science.gov (United States)

Fujimura, Koji; Conte, Matthew A.; Kocher, Thomas D.

2011-01-01

vasa is a highly conserved RNA helicase involved in animal germ cell development. Among vertebrate species, it is typically present as a single copy per genome. Here we report the isolation and sequencing of BAC clones for Nile tilapia vasa genes. Contrary to a previous report that Nile tilapia have a single copy of the vasa gene, we find evidence for at least three vasa gene loci. The vasa gene locus was duplicated from the original site and integrated into two distant novel sites. For one of these insertions we find evidence that the duplication was mediated by a circular DNA intermediate. This mechanism of gene duplication may explain the origin of isolated gene duplicates during the evolution of fish genomes. These data provide a foundation for studying the role of multiple vasa genes in the development of tilapia gonads, and will contribute to investigations of the molecular mechanisms of sex determination and evolution in cichlid fishes. PMID:22216289

Possible natural hybridization of two morphologically distinct species of Acropora (Cnidaria, Scleractinia in the Pacific: fertilization and larval survival rates.

Directory of Open Access Journals (Sweden)

Naoko Isomura

Full Text Available Natural hybridization of corals in the Indo-Pacific has been considered rather rare. However, field studies have observed many corals with intermediate interspecific or unusual morphologies. Given that the existence of F1 hybrids with intermediate interspecific morphologies has been proven in the Caribbean, hybrids may also inhabit the Indo-Pacific and occur more frequently than expected. In this study, we focused on two morphologically different species, Acropora florida and A. intermedia, and performed crossing experiments at Akajima Island, Japan. Results showed that these species could hybridize in both directions via eggs and sperm, but that fertilization rates significantly differed according to which species provided eggs. These results are similar to those reported from the Caribbean. Although all embryos developed normally to the planular larval stage, the developmental processes of some hybrid embryos were delayed by approximately 1 h compared with conspecific embryos, suggesting that fertilization occurred 1 h later in interspecific crosses than in intraspecific crosses. More successful hybridization could occur under conditions with low numbers of conspecific colonies. Additionally, a comparison of survival rates between hybrid and intraspecific larvae revealed that intra- and interspecific larvae produced from eggs of A. florida survived for significantly longer than those produced from eggs of A. intermedia. Considering these data, under specific conditions, hybrids can be expected to be produced and survive in nature in the Pacific. Furthermore, we identified one colony with intermediate morphology between A. florida and A. intermedia in the field. This colony was fertilized only by eggs of A. florida, with high fertilization rates, suggesting that this colony would be a hybrid of these two species and might be backcrossed.

Nausithoe aurea n. sp. (Scyphozoa: Coronatae: Nausithoidae), a species with two pathways of reproduction after strobilation: sexual and asexual

NARCIS (Netherlands)

Silveira, da Fábio Lang; Morandini, André Carrara

1997-01-01

Nausithoe aurea, a new species of scyphozoan Coronatae, is described from São Paulo State, Brazil. The solitary scyphistomae, with some zooxanthellae, strobilated producing planuloids and medusae; this represents an intermediate life cycle between that of metagenetic Nausithoidae and the submarine

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Full Text Available DNS.PSC.10.AllAg.iPSC_intermediates mm9 DNase-seq Pluripotent stem cell iPSC intermediates... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.PSC.10.AllAg.iPSC_intermediates.bed ...

File list: DNS.PSC.05.AllAg.iPSC_intermediates [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available DNS.PSC.05.AllAg.iPSC_intermediates mm9 DNase-seq Pluripotent stem cell iPSC intermediates... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.PSC.05.AllAg.iPSC_intermediates.bed ...

Timpanismo gastrointestinal em equídeos alimentados com Panicum maximum com alto conteúdo de amido

Directory of Open Access Journals (Sweden)

Taciane M. Souza

Full Text Available RESUMO: Timpanismo intestinal agudo em cavalos e mulas introduzidos em pastagens de Panicum maximum cv. Tanzânia, cv. Massai e cv. Mombaça são relatados na região norte do Brasil, durante o período das chuvas. As causas são desconhecidas, porém, tem sido sugerido que estão associados a um maior armazenamento de carboidratos não fibrosos na gramínea. Este trabalho teve por objetivos realizar um levantamento epidemiológico dos surtos de cólicas ocorridos no Estado de Rondônia, assim como contribuir com o estudo da ação dos carboidratos de P. maximum na ocorrência da doença. Para isso foram realizadas visitas em 10 propriedades que apresentaram casos da enfermidade. Em duas propriedades foram introduzidos equinos no mês de março e foram coletadas amostras de pastagens para a determinação de energia digestiva, lisina, matéria seca, carboidratos solúveis em água, carboidratos solúveis em éter, carboidratos não fibrosos, fibra de detergente neutra, fibra de detergente ácido, lignina, amido, gordura e proteína bruta. Essas determinações foram realizadas, também, em amostras de pastagens de P. maximum de outras propriedades onde não estavam ocorrendo cólicas e das pastagens de Cynodon dactylon de onde provinham os equinos. Os resultados mostraram que os surtos de cólica ocorrem na época de chuva, quando as pastagens estão rebrotando com uma morbidade de 31,6%, e letalidade de 86,1%. As análises bromatológicas mostraram uma diferença significativa nas concentrações de amido (P=0,0072 do P. maximum que causou cólica (8,3 % e 9,2%, quando comparado com o P. maximum das outras propriedades (0,9% e 4,3% e com o Tifton, utilizado previamente na alimentação dos mesmos equinos (0,2% e 0,8%. Em outra fazenda a doença foi reproduzida experimentalmente em um equino, no mês de março administrando P. maximum cortado contendo 6,5% de amido. A mesma pastagem não causou cólica quando foi administrada a equinos entre os

Intermediality and the Child Performer

Science.gov (United States)

Budd, Natasha

2016-01-01

This report details examples of praxis in the creation and presentation of "Joy Fear and Poetry": an intermedial theatre performance in which children aged 7-12 years generated aesthetic gestures using a range of new media forms. The impetus for the work's development was a desire to make an intervention into habituated patterns of…

Bioorthogonal Cycloadditions with Sub-Millisecond Intermediates.

Science.gov (United States)

Qing, Yujia; Pulcu, Gökçe Su; Bell, Nicholas A W; Bayley, Hagan

2018-01-26

Tetrazine- and sydnone-based click reactions have emerged as important bioconjugation strategies with fast kinetics and N 2 or CO 2 as the only byproduct. Mechanistic studies of these reactions have focused on the initial rate-determining cycloaddition steps. The subsequent N 2 or CO 2 release from the bicyclic intermediates has been approached mainly through computational studies, which have predicted lifetimes of femtoseconds. In the present study, bioorthogonal cycloadditions involving N 2 or CO 2 extrusion have been examined experimentally at the single-molecule level by using a protein nanoreactor. At the resolution of this approach, the reactions appeared to occur in a single step, which places an upper limit on the lifetimes of the intermediates of about 80 μs, which is consistent with the computational work. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Intermediate L-K molecular orbital radiation from heavy ion collisions