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Number of results: 16
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Abstract

The main issue of this article are eco-bridges, pedestrian-friendly imaginary sites (enclave) of greenery in urban tissues. Discussed cases include the implementations of projects such as: the High Line in New York and the Garden Bridge in London. The main theme of the article is to compare the green bridges in the urban tissue embedded with “living root bridges”. The author of the article highlights the potential limits for “living root bridges” in the urban tissue, resulting from the climate, time of their creation and limits of urban space. She also notes the strong tendency to create green areas in the “concrete” urban structure, but also the use of artificial materials in tissue of “living root bridges”.
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Abstract

Application of 1-naphthaleneacetic acid (NAA) or 1-aminocyclopropane-1-carboxilic acid (ACC) to maize roots growing in hydroponic solution inhibited root elongation, and increased radial growth, but the responses to those treatments differed in degree. Auxin was more effective than ACC as an elongation inhibitor and root swelling promoter. Whereas NAA fully inhibited elongation and maintained swelling over 48 h, ACC inhibited elongation partially (50%) and only promoted swelling for 24 h. It is well-known that auxin, like ACC, promotes ethylene production, but similar levels of ethylene production reached by means of NAA or ACC treatments did not elicit the same response, the response being always stronger to NAA than to ACC. These results suggest that the effect of auxin on root growth is not mediated by ethylene. Elongation and swelling of roots appear to be inversely related: usually a reduction in elongation was accompanied by corresponding swelling. However, these two processes showed different sensitivities to growth regulators. After 24 h treatment with 0.5 μM NAA or 5 μM ACC, root elongation was inhibited by 90% and 53% respectively, but the same treatments promoted swelling by 187% and 140% respectively. Furthermore, 1 μM ACC was shown to promote inhibition of root elongation without affecting swelling. The ethylene antagonist STS (silver thiosulfate) did not affect elongation in control or NAAtreated roots, but increased ethylene production and swelling. These results indicate that longitudinal and radial expansion could be independently controlled.
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Abstract

In this article I will try to describe the lesson learnt by the corporations from the grass root movements in the cities. In the proposed analysis I will refer to the conception of recuperation and a soul of capitalism – by Luc Boltanski and Ève Chiapello. Besides it I will refer to the works of these authors who analyse the beginnings and the activism of the city grass-root movements in a context of critique of capitalism and neoliberal system.
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Abstract

Secretory ducts and cavities of roots and rhizomes are typical features of the Cardueae tribe in the Asteraceae family. We used light microscopy to analyze the anatomy of the subterranean organs of 21 species of 13 genera of the Cardueae, with particular attention to the secretory system, interpreted in taxonomic terms. The anatomy of secretory ducts varied greatly. A new measurement quotient, C1 [length of epithelial cells (longitudinal section)] and C2 [length of adjacent cells (longitudinal section)] was established. Different types of ducts are described based on type of development and the size ratios among epithelial cells. Detailed anatomical descriptions of the ducts are given, together with their occurrence in particular taxa. The simultaneous presence of various secretory ducts within a single species and their spatial position relative to other prominent anatomical features provide valuable characters for discriminating the studied Cardueae species. These analyses are of particular interest for identification of herbal drugs as, besides chemical analytical techniques such as chromatographic fingerprinting, light microscopy is a common method for purity controls and thus required in official pharmacopeias.
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Abstract

Arbuscular mycorrizal (AM) fungi may enhance plant growth and polyphenol production, however, there have been limited studies on the relationships between root colonization of different fungal species and polyphenol production on cultivated Allium porrum (garden leek). The effects of inoculation of AM fungi spores from Rhizophagus intraradices, Giga -spora margarita, Glomus geosporum, Paraglomus occultum, Claroideoglomus claroideum, and Glomus species on colonization of garden leek roots and symbiotic changes in polyphenol production and plant growth were evaluated in greenhouse experiments. There were significant differences (p < 0.05) in colonization of leek roots by AM fungi species. The greatest level of root colonization was recorded on plants inoculated with R. intraradices (73%) and the lowest level on C. claroideum (3.2%). Significant differences (p < 0.05) in plant height were recorded between AM inoculated plants and the controls. Polyphenol levels differed significantly (p < 0.05) between garden leek plants inoculated with AM fungi and the non-inoculated controls. The percentage increases in polyphenol (a derivative of kaempferol) on garden leeks inoculated with G. geosporum relative to the untreated controls ranged from 28 to 1123%. Due to symbiosis with different AM species, other polyphenols decreased in some instances (negative values) and increased in others for values of up to 590%. Results showed that AM fungi species exhibited remarkable differences in polyphenol levels in garden leeks. The high polyphenol production by garden leek plants inoculated with G. geosporum, and Glomus species could be exploited for enhanced resistance of garden leeks to insects and diseases. This research highlights an understudied area, notably the relationships between AM fungal inoculations, root colonizations and polyphenol production in garden leeks. The findings can be utilized to improve pest resistance and the quality of garden leek plants.
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Abstract

Clethodim herbicide (Cle) and three Trichoderma strains (Tri) were applied either alone or in combination (Cle + Tri) for controlling weeds, root knot nematodes (Meloidogyne arenaria) and Rhizoctonia root rot disease (Rhizoctonia solani) as well as for evaluating their effects on total microbial count in the rhizosphere and the number of Rhizobium nodules on roots in two faba bean cultivars cultivated in naturally heavily infested fields. The evaluated characters were very similar for the two tested cultivars (Nubariya 1 and Sakha 3). Treatment with Cle alone highly reduced the fresh and dry matter of tested weeds (Amaranthus viridis, Cynodon dactylon and Cenchrus ciliaris), followed by Cle + Tri and Tri alone. Cle + Tri highly reduced nematode parameters viz. numbers of J2 in soil or roots, females, eggs, galls and egg-masses when compared with each treatment alone. Tri alone caused a great decrease in Rhizoctonia root rot infection, followed by Cle + Tri and Cle alone. Total microbial count and Rhizobium nodules were affected only with Cle treatment. Plant growth parameters (shoot length, shoot fresh and dry weight and numbers of branches and leaves) and yield parameters (fresh pod and dry weight, seed number per pod, seed weight and ash pod weight of plant) were greatly improved for Cle + Tri treatments when compared with either Tri or Cle alone.
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Abstract

My series “Some Berber Etymologies” is to gradually reveal the still unknown immense Afro-Asiatic heritage in the Berber lexical stock. The first part with some miscellaneous Berber etymologies was published back in 1996. Recently, I continued the series according to initial root consonants1 in course of my research for the volumes of the “Etymological Dictionary of Egyptian” (abbreviated as EDE, Leiden, since 1999, Brill)2 with a much more extensive lexicographical apparatus on the cognate Afro-Asiatic daughter languages. As for the present part, it greatly exploits the results of my ongoing work for the the fourth volume of EDE (analyzining the Eg. lexical stock with initial n-). The present part contains etymologies of Berber roots with initial *n- followed by dental stops. The numeration of the entries continues that of the preceding parts of this series. In order to spare room, I quote those well-attested and widespread lexical roots that appear common Berber, only through a few illustrative examples. The underlying regular consonant correspondences between Berber vs. Afro-Asiatic agree with those established by the Russian team of I.M. Diakonoff and summarized by A.Ju. Militarev (1991, 242–3).
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Abstract

The response of the Mi-1 gene to different densities of Meloidogyne incognita race 2 was investigated under controlled conditions. Susceptible and resistant tomato seedlings were inoculated with 25, 50, 100, 200, 400, 1000, 2000, 5000 and 10000 second-stage juveniles of M. incognita. Plants were uprooted 8 weeks after inoculation and the numbers of egg masses and galls on the roots, and second-stage juveniles in 100 g soil per pot were counted. In susceptible plants, there was a correlation between the number of egg masses on roots until 2000 J2 inoculum densities. In resistant plants, when inoculum densities increased, the number of egg masses and galls also increased. The reproduction factor ratio was >1 in the susceptible plant and <1 in the resistant plant. The data showed that the 5000 J2 inoculum was a critical limit, and 10000 J2s were above threshold for resistant plants. The data indicate that densities of M. incognita can seriously affect the performance of the Mi-1 gene.
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Abstract

It has long been observed that toxic heavy metals at different concentrations can induce root hair development in plants. In oilseed rape we studied ethylene levels and root hair initiation under Cd2+ stress. Growth of the primary root was inhibited but close to root tips the development of subapical root hairs was significantly stimulated by Cd2+ at 30 μM. Versus the control, the distance between the root tip and the root hair zone and the length of the epidermal cell in the elongation zone were significantly reduced by Cd2+ at the same concentration. Exogenous application of Cd2+ and 1-aminocyclopropane-1-carboxylate (ACC) to roots had similar effects on subapical root hair development. Hair density increase and hair elongation in the presence of Cd2+ were reduced by the ethylene inhibitors CoCl2 at 15 μM and aminooxyacetic acid (AOA) at 10 μM. Exposing roots to Cd2+ caused a rapid increase in superoxide radical (O2 ·-) production in the root hair differentiation zone, and at the tips of emerging and newly formed root hairs. Cd2+-induced O2 ·- production at the growing hair tips was blocked in the presence of AOA. Our findings suggest that Cd2+-induced ethylene signaling may act upstream of O2 ·-. Cd2+ promotion of O2 ·- production may operate through an ethylene signaling pathway, and O2 ·- itself may stimulate root hair elongation.
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Abstract

The study examined tyrosol glucosyltransferase activity and the efficiency of salidroside production in natural and transformed root cultures of Rhodiola kirilowii (Regel) Regel et Maximowicz. Neither enzyme activity nor salidroside accumulation were detected in natural and transformed root cultures maintained in media without tyrosol. To induce TGase activity in biotransformation reactions, tyrosol was added to natural and transformed root cultures on the day of inoculation. The first peak of TGase activity (0.23 U/μg) was detected on day 9 in natural root culture, accompanied by the highest salidroside content (15.79 mg/g d.w.), but TGase activity was highest (0.27 U/μg) on day 15. In transformed root culture, day 18 showed the highest TGase activity (0.15 U/μg), which coincided with the highest salidroside content (2.4 mg/g d.w.). Based on these results, tyrosol was added to the medium on the days of highest previously detected activity of TGase: day 15 for natural root cultures and day 18 for transformed root cultures. This strategy gave significantly higher yields of salidroside than in the cultures supplemented with tyrosol on the day of inoculation. In natural root culture, salidroside production reached 21.89 mg/g d.w., while precursor feeding in transformed root cultures caused a significant increase in salidroside accumulation to 7.55 mg/g d.w. In all treatments, salidroside production was lower in transformed than in natural root cultures.
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Abstract

We examined whether peroxidase activity in cutting bases and leaves and starch content in cutting bases can be used as rooting phase markers in the elepidote rhododendron cv. ‘Babites Baltais’ (Rhododendron L.). Changes in peroxidase activity in cutting leaves and bases, as well as starch content in cutting bases, were determined in relation to anatomical stages of rhizogenesis in leaf bud cuttings treated with 1% indole-3-butyric acid (IBA+) or without IBA (IBA-). The pattern of change of peroxidase activity was similar in cutting bases and leaves of IBA- leaf bud cuttings. Three phases of adventitious root formation were identified: induction, initiation and expression. During the induction phase peroxidase activity decreased, but no anatomical changes were observed in the cuttings. Peroxidase activity increased in the initiation phase when adventitious root initials were formed. Peroxidase activity decreased during the expression phase when adventitious root primordia developed. The starch content of IBA- leaf bud cuttings decreased during the first few days and then gradually rose to maximum, followed by a sharp reduction and another increase at the end of the experiment. The changes of starch content did not coincide with rooting phases as peroxidase activity did, and cannot be used as a rooting phase marker in rhododendrons. Adventitious root formation did not occur in IBA+ leaf bud cuttings, so distinct rooting phases could not be observed. There was a significant correlation between peroxidase activity in cutting bases and leaves of IBA- leaf bud cuttings. Peroxidase activity in leaves of rhododendron leaf bud cuttings are potentially useful as a marker for rooting phases, but that requires further anatomical and physiological study of rooting in leaf bud cuttings.
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Abstract

There is a considerable increase in the use of noise barriers in recent years. Noise barriers as a control noise solution can increase the insertion loss to protect receivers. This paper presents the results of an investigation about the acoustic efficiency of primitive root sequence diffuser (PRD) on an environmental single T-shape barrier design. A 2D boundary element method (BEM) is used to predict the insertion loss of the tested barriers. The results of rigid and with a different sequence diffuser coverage are also predicted for comparison. Employing PRD on the top surface of T-shape barrier has been found to improve the performance of barriers in comparison with the use of rigid and QRD coverage at the examined receiver locations. It has been found that decreasing the design frequency of PRD shifts the frequency effects towards lower frequencies, and therefore the overall A-weighted insertion loss is improved. It was also found that using wire mesh with reasonably efficient resistivity on the top surface of PRD improves the efficiency of the reactive barriers; however utilizing wire meshes with flow resistivity higher than the specific acoustic impedance of air on the PRD top of a diffuser barrier significantly reduces the performance of the barrier within the frequency bandwidth of the diffuser. The performance of a PRD covered T-shape barrier at 200 Hz was found to be higher than that of its equivalent QRD barriers in both the far field and in areas close to the ground. The amount of improvement compared made by PRD barrier compared with its equivalent rigid barrier at far field is about 2 to 3 dB, while this improvement relative to the barrier model "QR4" can reach up to 4-6 dB.
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Abstract

Root associated bacteria were isolated from Suaeda nudiflora and two isolates were selected for this study: rhizospheric Bacillus megaterium and endophytic Pseudomonas aeruginosa. These isolates were inoculated into maize variety Narmada Moti during its germination. TTC (2, 3, 5-triphenyl tetrazolium chloride) staining was used to confirm the association of the isolates with the maize root. The effects of these root associated bacteria were tested alone and in combinations for cell wall reinforcement and the induction of defense enzymes such as phenylalanine ammonia lyase (PAL) and β-1,3-glucanase in the presence of fungal pathogen Aspergillus niger in maize. The results indicated that the rhizospheric bacteria had a greater fight response to fungal infection than the endophhytic bacteria due to cell wall lignification as well as the rapid induction of higher concentrations of defense related enzymes.
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Abstract

This study presents a customized root cause analysis approach to investigate the reasons, provide improvements measures for the cost overruns, and schedule slippage in papermachine- building projects. The proposed approach is an analytical-survey approach that uses both actual technical data and experts’ opinions. Various analysis tools are embedded in the approach including: data collection and clustering, interviews with experts, 5-Whys, Pareto charts, cause and effect diagram, and critical ratio control charts. The approach was implemented on seven projects obtained from a leading international paper machine supplier. As a result, it was found that the main causes behind cost and schedule deviations are products’ related; including technical accidents in the Press section, damaged parts, design issues, optimization of the machine and missing parts. Based on the results, prevention measures were perceived.
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Abstract

The aim of this paper is to conduct a diachronic analysis of the Polish word rżysko ‘stubble’, whose root retains the primary designation of rye, namely reż ‘rye, obs.’. Although this noun was ousted by żyto ‘rye’, a derivative of the verb żyć ‘to live’, its cognates are still used in many Slavic and Germanic languages, e.g. Russian rožь (рожь) ‘rye’, and English rye. The paper presents other cognates with a view to contrasting the English word rye with its obsolete Polish cognate reż and understanding the evolution of both words. For this purpose, the study seeks to identify the sound changes responsible for the discrepancy between the Polish-English cognates which developed from *rughi-. The derivative rżysko ‘stubble’ has been analysed in the context of other nomina loci as well as the semantic change which affected the word. It is suggested that the phenomenon exemplifi ed by rżysko can be referred to as a root archaism.
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Abstract

The national total expenditure of a country is precipitated on several factors of which revenue generated could be one and very significant. This paper therefore examines the contribution of some selected sources of Nigerian government revenue to total national expenditure. Statistical and econometric techniques used for the data analysis are unit root test, cointegration test, combined estimators’ analysis, the error correction model (ECM) and the feasible generalized linear (FGLS) estimators. Results showed that the variables are non stationary but are stationary at first difference. The long-run relationship of total expenditure on oil revenue, non-oil revenue, federation account and federal retained revenue revealed that the variables are co-integrated and required the use of combined estimators. The effect of non-oil revenue and federal retained revenue is very significant. Investigations on the short-run modeling necessitated the use of FGLS estimators. The effect of ECM and federal retained revenue is very significant. Consequently, other sources of revenue apart from federal retained revenue need to be enhanced and tailored towards improving economic growth and development through national expenditure.
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