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Roots
Kinds of Roots Terms modified by Roots Selected AbstractsIS THERE UNIT ROOT IN THE NITROGEN OXIDES EMISSIONS: A MONTE CARLO INVESTIGATION?NATURAL RESOURCE MODELING, Issue 1 2010NINA S. JONES Abstract Use of the time-series econometric techniques to investigate issues about environmental regulation requires knowing whether air pollution emissions are trend stationary or difference stationary. It has been shown that results regarding trend stationarity of the pollution data are sensitive to the methods used. I conduct a Monte Carlo experiment to study the size and power of two unit root tests that allow for a structural change in the trend at a known time using the data-generating process calibrated to the actual pollution series. I find that finite sample properties of the Perron test are better than the Park and Sung Phillips-Perron (PP) type test. Severe size distortions in the Park and Sung PP type test can explain the rejection of a unit root in air pollution emissions reported in some environmental regulation analyses. [source] Root and butt rot of Todo fir (Abies sachalinensis) caused by Heterobasidion annosum s.l. in Hokkaido, JapanFOREST PATHOLOGY, Issue 3 2007S. Tokuda Summary The occurrence and symptoms of root and butt rot were examined in a 35 × 30 m plot of 68-year-old Todo fir plantation in Hokkaido, Japan. Forty-seven percent of the cut stumps were decayed and 52% of the decayed stumps showed similar decay characteristics with yellowish orange to light brown colouration and expanded pockets in the heartwood. Morphological characteristics of the pure cultures isolated from the decay were similar to the cultures isolated from basidiocarps of Heterobasidion annosum sensu lato, found on fallen logs outside of the research site. Also DNA analysis based on the combined data set of three gene loci (glyceraldehyde 3-phosphate dehydrogenase, heat shock protein 80,1 and elongation factor 1-alpha genes) showed that the isolates from the decay are included in the same clade with the Japanese H. annosum s.l. isolates. They form a subclade to H. parviporum (the European S group of H. annosum s.l.). This is the first report of molecular determination of H. annosum s.l. isolated from root and butt rot in a plantation in Japan. [source] Root and rhizome systems of perennial grasses grown in Inner Mongolian grassland, ChinaGRASSLAND SCIENCE, Issue 4 2009Min Ao Abstract The root and rhizome systems of dominant perennial grasses in Inner Mongolian grassland were clarified. We surveyed the vertical distribution of root and rhizome biomass in the natural stands, and the changes of under-ground biomass and the branching pattern of rhizomes for transplanted plants in a container experiment. Most roots of Leymus chinensis, Bromus inermis, Elymus dahuricus and Agropyron cristatum were distributed in the soil depth of 0,10 cm. Roots of E. dahuricus and A. cristatum were distributed in a shallower soil layer, but those of L. chinensis and B. inermis were distributed in a deeper soil layer. Biomass of above-ground parts increased with growth, resulting in a decreasing ratio of under-ground parts to total biomass. Rhizomes of L. chinensis and B. inermis were distributed in the soil depth of 0,10 cm, but E. dahuricus and A. cristatum did not have rhizomes. L. chinensis had longer rhizomes and new ramets were produced away from their mother plant. B. inermis had many short rhizomes and produced daughter plants near their mother plant. [source] Two New Endiandric Acid Analogs, a New Benzopyran, and a New Benzenoid from the Root of Beilschmiedia erythrophloiaHELVETICA CHIMICA ACTA, Issue 11 2008Ping-Shin Yang Abstract Phytochemical investigation of the root of Beilschmiedia erythrophloia led to the isolation and structural elucidation of two new endiandric acid analogs, endiandric acids I and J (1 and 2, resp.), a new benzopyran, dehydrooligandrol methyl ether (3), and a new benzenoid, farnesylol (4), together with six known compounds. Their structures were established on the basis of extensive 1D- and 2D-NMR analyses in combination with HR-MS experiments. [source] Influence of endodontic treatment, post insertion, and ceramic restoration on the fracture resistance of maxillary premolarsINTERNATIONAL ENDODONTIC JOURNAL, Issue 6 2010K. Bitter Bitter K, Meyer-Lueckel H, Fotiadis N, Blunck U, Neumann K, Kielbassa AM, Paris S. Influence of endodontic treatment, post insertion, and ceramic restoration on the fracture resistance of maxillary premolars. International Endodontic Journal, 43, 469,477, 2010. Abstract Aim, To investigate the effects of endodontic treatment, post placement and ceramic restoration type on the fracture resistance of premolars. Methodology, One hundred and twenty teeth maxillary premolars were allocated to four groups (A,D; n = 30). In group A, mesio-occlusal-distal-inlays with a buccal and palatal wall of 2 mm (MOD), in group B partial onlays with palatal cusp coverage and in group C total onlays with buccal and palatal cusp coverage were prepared. Group D served as untreated controls. Groups A,C were divided into three subgroups (n = 10): (i) teeth received solely the described preparations, (ii) teeth were root filled, (iii) teeth were root filled and quartz fibre posts were placed. Teeth were restored using Computer-assisted design/computer-assisted machining-ceramic-restorations and subjected to thermo-mechanical-loading; subsequently, the buccal cusp was loaded until fracture. Results, Group D revealed significantly higher fracture resistance [mean (standard deviation)] [738 (272) N] compared to all other groups (P < 0.05; post hoc test Dunnett). For groups A,C, fracture resistance was significantly affected by the restoration type (P = 0.043) and endodontic treatment/post placement (P = 0.039; 2-way anova). Group A [380 (146) N] showed significantly lower fracture resistance compared to group B [470 (158) N] (P = 0.048; post hoc test Tukey). Compared to non-endodontically treated teeth [487 (120) N], root filled teeth revealed significantly lower fracture resistance [389 (171) N] (P = 0.031). Conclusion, The restoration of cavities with a remaining wall thickness of 2 mm using ceramic MOD-inlays is inferior with respect to the fracture resistance compared to partial onlay restorations. Root filled teeth without post placement show lower fracture resistance compared to non-endodontically treated teeth. [source] Root and canal morphology of permanent mandibular molars in a Sudanese populationINTERNATIONAL ENDODONTIC JOURNAL, Issue 10 2007H. A. Ahmed Abstract Aim, To investigate variations in the root canal systems of first and second permanent mandibular molar teeth in a Sudanese population using a clearing technique. Methodology, Two hundred extracted first and second permanent mandibular molars from three cities in the state of Khartoum were studied. Access cavities were prepared and pulp tissue was removed by immersion in 5% sodium hypochlorite under ultrasonication; Indian ink was then injected into the root canal systems assisted by a vacuum applied apically. The teeth were rendered clear by demineralization and immersion in methyl salicylate before evaluation. The following observations were made (i) number of roots and their morphology; (ii) number of root canals per tooth; (iii) number of root canals per root and (iv) root canal configuration. Results, Overall 59% of mandibular first molars had four canals with 3% having a third distolingual root. Seventy-eight per cent of second mandibular molars had two separate flat roots, whilst 10% were C-shaped. The most common canal system configurations were type IV (73%) and type II (14%). Inter-canal communications were more common in the mesial roots. The prevalence of inter-canal communications was 65% in first molars and 49% in second molars. Conclusions, In this sample of Sudanese teeth, 59% of the mandibular first permanent molars had four root canals whilst 10% of the mandibular second molars had C-shaped roots/canals. [source] Root and canal morphology of maxillary first and second permanent molar teeth in a Ugandan populationINTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2007C. M. Rwenyonyi Abstract Aim, To investigate the root and canal morphology of permanent maxillary molar teeth from a Ugandan population. Methodology, Maxillary first (n = 221) and second molar (n = 221) teeth were collected from patients attending dental clinics in Kampala. Teeth were prepared using a clearing technique: the pulp chambers were accessed and the teeth placed consecutively into 5% sodium hypochlorite, 10% nitric acid, then methyl salicylate. Indian ink was injected into the pulp chambers to demonstrate the canal system. Results, In the first molars, 95.9% of the teeth had separate roots. The mesiobuccal root was fused with the palatal root in 3% of specimens and with the distobuccal root in 0.5% of teeth. In the second molars, 86% of the teeth had separate roots. The mesiobuccal root was fused with the palatal root in 6.3% of specimens and with the distobuccal root in 6.8% of teeth. Apical deltas were more frequent in the mesiobuccal root when compared with distobuccal and palatal roots of both the first and second molars. A type I canal configuration (>75%) was the most frequent in all the roots of both the first and second molars. Canal intercommunications and lateral canals were more frequent in the mesiobuccal root when compared with other roots. Conclusions, The mesiobuccal root tended to have more variations in the canal system followed by the distobuccal root, whereas the palatal root had the least. The findings in root and canal morphology of this Ugandan population were different from previous studies, which may partly be attributed to racial differences. [source] Space allocation in Melanophila knoteki knoteki (Reitt.) var. hellenica (Obenberger) (Col., Buprestidae) in the attack of Greek fir [Abies cephalonica Loud. var. graeca (Fraas) Liu]: a pattern to process approachJOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2004P. V. Petrakis Abstract: The phloeo-cambiophagous buprestid Melanophila knoteki knoteki (Reitt.) var. hellenica (Obenberger.) is not a primary factor of fir decline problem although the beetle substantially contributes to Greek fir Abies cephalonica Loud. var. graeca (Fraas) Liu mortality. By using mapping depiction of the exit holes of the insect on a set of fir trees located on a line transect in a randomized point-centred quarter scheme and employing pattern analysis techniques we were able to reveal various scales of the infestation pattern. Four scales were recognized, two of them corresponding to the pattern of microsite selection on the bark of a fir tree. While the dispersed exit holes exhibited a statistically significant random dispersion on the bark, within each aggregation the pattern was uniform. The area of compartments created by Dirichlet partition approximated very well the sizes of the actual larval galleries. The Dirichlet tessellation of the bark space and the analysis of the parameter of the resulting partitions showed the predominance of the hexagonal conformation of the larval spaces when space was limited. When some exit holes were positioned close together it was found that they were directed away from each other so the resulting galleries were well separated. Several hypotheses are presented as to the mechanisms underpinning the observed patterns. The allocation of space is in accordance with the widely accepted ,central place theory' of W. Christaller, a general theory of pattern generated in the geographical dispersion of human settlements. The revealed pattern was also in accordance with the predictions of the theory of ,central place foraging' of R. H. MacArthur and the theory of ,resource concentration hypothesis' of R. Root. [source] Does Aortic Root Enlargement Impair the Outcome of Patients With Small Aortic Root?JOURNAL OF CARDIAC SURGERY, Issue 5 2006Hasan Ardal The aim of this study was to evaluate long-term results of the posterior root enlargement. Methods: Between 1985 and 2002, 124 patients underwent aortic valve replacement with a posterior root enlargement. The main indication was a small aortic valve orifice area to patient body surface area (indexed valve area < 0.85 cm2/m2). Fifty-four (44%) patients were male, and 70 (56%) were female with a mean age 39.1 ± 14.3 years. Indications for operation were severe calcified aortic valve stenosis (37.1%), severe aortic insufficiency (25.8%), or combination (37.1%). Seventy-five (60%) patients received double-valve replacement. A pericardial patch was used in 100 patients (80.6%) and a Dacron patch was used in 24 patients. Results: Operative mortality was 6.4% (8 patients). The causes of hospital mortality were low cardiac output syndrome (LCOS) (in 6 patients), cerebrovascular events (in 1 patient) and multiple organ failure (in 1 patient). Multivariate analysis demonstrated concomitant coronary revascularization to be a significant (p = 0.03) predictor for early mortality. There were six (5.4%) late deaths. Cox proportional hazards regression analysis demonstrated LCOS (p = 0.013) and infective endocarditis (p = 0.003) to be significant predictors for late mortality. Atrioventricular block required a permanent pacemaker was observed in 4 patients (3.2%). Conclusions: Posterior aortic root enlargement techniques can be easily applied without additional risks. Long-term survival and freedoms from valve-related complications are satisfactory. [source] Hairy Root and Its Application in Plant Genetic EngineeringJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 2 2006Zhi-Bi Hu Abstract Agrobacterium rhizogenes Conn. causes hairy root disease in plants. Hairy root-infected A. rhizogenes is characterized by a high growth rate and genetic stability. Hairy root cultures have been proven to be an efficient means of producing secondary metabolites that are normally biosynthesized in roots of differentiated plants. Furthermore, a transgenic root system offers tremendous potential for introducing additional genes along with the Ri plasmid, especially with modified genes, into medicinal plant cells with A. rhizogenes vector systems. The cultures have turned out to be a valuable tool with which to study the biochemical properties and the gene expression profile of metabolic pathways. Moreover, the cultures can be used to elucidate the intermediates and key enzymes involved in the biosynthesis of secondary metabolites. The present article discusses various applications of hairy root cultures in plant genetic engineering and potential problems associated with them. (Managing editor: Wei Wang) [source] Perforation of Aortic Root as Secondary Complication after Implantation of Patent Foramen Ovale Occlusion Device in a 31-Year-Old WomanJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 2 2006STEFAN A. LANGE M.D. Transesophageal echocardiography (TEE) revealed a 3-mm-large patent foramen ovale (PFO). No other reason for these neurological events could be found and the patient underwent percutaneous closure of the PFO with a CARDIA® Star 03/30 device without periprocedural complications. Four weeks later, the patient underwent a routine control of device without any adverse clinical symptoms. Surprisingly, echocardiography revealed a perforation of the aortic root by an umbrella strut with a small shunt from the aortic root to the right atrium. Magnetic resonance imaging (MRI) confirmed the diagnosis of device malposition. Consecutively, the patient underwent minimal invasive surgery. After removal of the single perforating strut, the bleeding lesion was closed. The patient remained free of any additional complications during the postoperative course and up until now has had uneventful follow-ups. [source] Identity and Pathogenicity of Fungi Associated with Root and Crown Rot of Soft Red Winter Wheat Grown on the Upper Coastal Plain Land Resource Area of MississippiJOURNAL OF PHYTOPATHOLOGY, Issue 2 2000M. S. Gonzalez Seedling stand, disease severity and fungal incidence were determined from untreated ,Wakefield' soft red winter wheat planted on a Leeper silty clay loam in field tests conducted at the Mississippi Agricultural and Forestry Experiment Station, Plant Science Research Center, Mississippi State University, Starkville, Mississippi during the 1996,97 and 1997,98 growing seasons. Seedling stand was reduced by 40% each year in plots established with untreated seed. Cochliobolus sativus was the most frequently isolated fungus. Fusarium acuminatum, Fusarium equiseti and Fusarium solani were the most prevalent Fusarium spp. Seven other Fusarium spp. and 23 species of other fungal genera were isolated. Pathogenicity tests with three isolates each of C. sativus, Cochliobolus spicifer, F. acuminatum, F. solani, F. equiseti, Fusarium compactum, Embellisia chlamydospora and Microdochium bolleyi were performed in test tube culture and two isolates each of C. sativus, C. spicifer, F. acuminatum, E. chlamydospora and M. bolleyi under greenhouse conditions. In test tubes and in the greenhouse, seedlings infected with isolates of C. sativus developed seedling blight, discoloration and necrosis, primarily in seminal roots and crowns. In the greenhouse, C. sativus induced lesions on the lower leaf sheath and reduced seedling height, seedling emergence, dry and fresh weight of roots and shoots. Isolates of F. acuminatum, F. solani, F. equiseti, F. compactum, E. chlamydospora and M. bolleyi induced slight to moderate orange to light-brown discoloration of crown and seminal roots in test tubes. Cochliobolus spicifer isolates had the most pre-emergence activity, inducing black root discoloration and root pruning of wheat seedlings and reducing seedling emergence, root fresh weight and shoot dry weight. In the greenhouse, F. acuminatum reduced seedling height, seedling emergence and root and shoot dry weights. Microdochium bolleyi and E. chlamydospora reduced fresh and dry weight of roots, plant emergence and shoot dry weight. Fusarium acuminatum and C. spicifer reduced the growth rate of wheat seedlings. All fungi evaluated showed increased disease severity compared to the untreated control. The high frequency of isolation of C. sativus from crown and root tissues can be partially explained by the dry, warm conditions during the early stages of wheat seedling development in the Upper Coastal Plain Land Resource Area of Mississippi. Zusammenfassung Die Auflaufrate von Sämlingen, die Stärke des Krank-heitsbefalls sowie die Häufigkeit von Pilzarten wurden bei nicht behandelten roten Weichwinterweizen der Sorte Wakefield ermittelt, welche in einem Leeper schlammigen Tonboden an der Mississippi Agricultural & Forestry Experiment Station, Plant Science Research Center, Mississippi State University, Starkville, Mississippi in der 1996,97 und 1997,98 Saison gesät worden waren. In beiden Jahren wurde die Auflaufrate von nicht behandeltem Saatgut um 40% reduziert. Cochliobolus sativus wurde am häufigsten isoliert. Fusarium acuminatum, Fusarium equiseti und Fusarium solani waren die überwiegenden Fusarium spp. Außierdem wurden sieben weitere Fusarium spp. sowie 23 weitere Pilzarten isoliert. Pathogenitätstests mit je 3 Isolaten von C. sativus, Cochliobolus spicifer, F. acuminatum, F. solani, F. equiseti, Fusarium compactum, Embellisia chlamydospora und Microdochiumbolleyi wurden in Reagenzröhrchen durchgeführt, sowie mit je 2 Isolaten von C. sativus, C. spicifer, F. acuminatum, E. chlamydospora und M. bolleyi unter Gewächshausbedingungen. Sowohl in den Reagenzröhrchen als auch im Gewächshaus entwickelten Sämlinge, die mit C. sativus inokuliert worden waren, eine Fäule, Verfärbung sowie Nekrosis, hauptsächlich in den sekundären Wurzeln und in den Halmbasen. Unter Gewächshausbedingungen verursachte C. sativus außierdem Läsionen der unteren Blattscheide sowie eine Reduzierung des Sämlingswachstums, des Sämlingsauflaufs, des Trocken-und Frischgewichts der Wurzeln und Sprossen. Im Reagenzröhrchentest induzierten Isolate von F. acuminatum, F. solani, F. equiseti, F. compactum, E. chlamydospora und M. bolleyieine schwache bis mäßiige orange bis hell braune Verfärbung des Halmbasis und der Sekundärwurzeln. Isolate von C. spicifer besaßien die höchste Vorauflaufaktivität und induzierten eine Verschwärzung und Verkürzung der Wurzeln sowie eine Reduzierung des Sämlingsauflaufs, des Wurzelfrischgewichts sowie des Sproitrockengewichts. Unter Gewächshausbedingungen reduzierte F. acuminatum die Sämlingshöhe, die Auflaufrate sowie das Trockengewicht der Wurzeln und Sproien. Microdochium bolleyi und E. chlamydospora reduzierten das Frisch-und Trockengewicht der Wurzeln, die Auflaufrate sowie das Sproßitrockengewicht. Die Wachstumsrate der Sämlinge wurde durch F. acuminatum und C. spicifer reduziert. Alle untersuchten Pilzarten erhöhten die Befallsstärke verglichen mit der unbehandelten Kontrolle. Die hohe Isolierungsrate von C. sativus aus dem Halmbasis-und Wurzelgewebe kann zum Teil dadurch erklärt werden, dass während der Frühentwicklungsphase der Sämlinge trockene und warme Wachstumsbedingungen in diesem Gebiet herrschten. [source] Population analysis using the nuclear white gene detects Pliocene/Pleistocene lineage divergence within Anopheles nuneztovari in South AmericaMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2008L. MIRABELLO AbstractAnopheles (Nyssorhynchus) nuneztovari Gabaldón (Diptera: Culicidae), a locally important malaria vector in some regions of South America, has been hypothesized to consist of at least two cryptic incipient species. We investigated its phylogeographic structure in several South American localities to determine the number of lineages and levels of divergence using the nuclear white gene, a marker that detected two recently diverged genotypes in the primary Neotropical malaria vector Anopheles darlingi Root. In An. nuneztovari, five distinct lineages (1,5) were elucidated: (1) populations from northeastern and central Amazonia; (2) populations from Venezuela east and west of the Andes; (3) populations from Colombia and Venezuela west of the Andes; (4) southeastern and western Amazonian Brazil populations, and (5) southeastern and western Amazonian Brazil and Bolivian populations. There was a large amount of genetic differentiation among these lineages. The deepest and earliest divergence was found between lineage 3 and lineages 1, 2 and 4, which probably accounts for the detection of lineage 3 in some earlier studies. The multiple lineages within Amazonia are partially congruent with previous mtDNA and ITS2 data, but were undetected in many earlier studies, probably because of their recent (Pleistocene) divergence and the differential mutation rates of the markers. The estimates for the five lineages, interpreted as recently evolved or incipient species, date to the Pleistocene and Pliocene. We hypothesize that the diversification in An. nuneztovari is the result of an interaction between the Miocene/Pliocene marine incursion and Pleistocene climatic changes leading to refugial isolation. The identification of cryptic lineages in An. nuneztovari could have a significant impact on local vector control measures. [source] Heat shock protein 101 effects in A. thaliana: genetic variation, fitness and pleiotropy in controlled temperature conditionsMOLECULAR ECOLOGY, Issue 6 2008S. J. TONSOR Abstract The Hsp100/ClpB heat shock protein family is ancient and required for high temperature survival, but natural variation in expression and its phenotypic effects is unexplored in plants. In controlled environment experiments, we examined the effects of variation in the Arabidopsis cytosolic AtHsp101 (hereafter Hsp101). Ten wild-collected ecotypes differed in Hsp101 expression responses across a 22 to 40 °C gradient. Genotypes from low latitudes expressed the least Hsp101. We tested fitness and pleiotropic consequences of varying Hsp101 expression in ,control' vs. mild thermal stress treatments (15/25 °C D/N vs. 15/25° D/N plus 3 h at 35 °C 3 days/week). Comparing wild type and null mutants, wt Columbia (Col) produced ~33% more fruits compared to its Hsp101 homozygous null mutant. There was no difference between Landsberg erecta null mutant NIL (Ler) and wt Ler; wt Ler showed very low Hsp101 expression. In an assay of six genotypes, fecundity was a saturating function of Hsp101 content, in both experimental treatments. Thus, in addition to its essential role in acquired thermal tolerance, Hsp101 provides a substantial fitness benefit under normal growth conditions. Knocking out Hsp101 decreased fruit production, days to germination and days to bolting, total dry mass, and number of inflorescences; it increased transpiration rate and allocation to root mass. Root : total mass ratio decayed exponentially with Hsp101 content. This study shows that Hsp101 expression is evolvable in natural populations. Our results further suggest that Hsp101 is primarily an emergency high-temperature tolerance mechanism, since expression levels are lower in low-latitude populations from warmer climates. Hsp101 expression appears to carry an important trade-off in reduced root growth. This trade-off may select for suppressed expression under chronically high temperatures. [source] Frozen in time: a new method using cryo-scanning electron microscopy to visualize root,fungal interactionsNEW PHYTOLOGIST, Issue 2 2006Steve Refshauge Summary ,,A new method of sample preparation for cryo-scanning electron microscopy was used to visualize internal infection of wheat (Triticum aestivum) roots by the pathogenic fungus Rhizoctonia solani AG-8. The new method retained fungal hyphae and root cells in situ in disintegrating root tissues, thus avoiding the distortions that can be introduced by conventional preparation by chemical fixation, dehydration and embedding. ,,Infected roots frozen in liquid nitrogen were cryo-planed and etched (sublimed) at ,80°C for a critical length of time (up to 9 min) in the microscope column to reveal plant and fungal structures in three dimensions. ,,Root and fungal structures were well preserved irrespective of infection severity. Root and hyphal cell walls were clearly seen and hyphal architecture within and between root cells was preserved. ,,This rapid method permits three-dimensional in situ visualization of fungal invasion within roots and has broad application for examination of diseases caused by other necrotrophic fungi. [source] Allometry of Salsola collina in response to soil nutrients, water supply and population densityNORDIC JOURNAL OF BOTANY, Issue 6 2009Yingxin Huang The allometry of greenhouse-grown Salsola collina Pall. in response to variation in soil nutrient content, water supply and population density has been compared. The results showed that the biomass allocation was size-dependent. Root, stem, leaf and reproductive allocation showed a ,true' plasticity in response to soil nutrient variation. At low soil nutrient content, plants tended to allocate more biomass to the development of reproductive organs than to stem and leaf, but root allocation was consistent due to a tradeoff between the effects of plant size and soil nutrient content. The plasticity of stem allocation and reproductive effort was ,true', while the plasticity of root allocation was ,apparent', but there was no plasticity for leaf allocation in response to soil water variation. At lower soil water content, plants tended to allocate more biomass to the stem than to development of reproductive organs. With the exception of ,apparent' plasticity of root allocation, no plasticity was detected in biomass allocation when population density was varied. [source] Root Causes of Peacelessness and Approaches to Peace in AfricaPEACE & CHANGE, Issue 2 2000Yash Tandon Conflicts are endemic in society, but what is their specific nature in Africa, and why do they deteriorate into such intense violence as negates humanity itself? This article looks at the "mainstream" theorythat attempts to explain this, taking as example the UN secretary-general's recent report on the subject. The report is both partial and ideological; it seeks to hide the systemic causes of poverty and conflict in Africa. The role of the peace activist is to understand conflict in Africa from a holistic and systemic perspective. He or she must work at various levels to alleviateconflict and prevent its degeneration into violence, based on the dual strategy of partially de-linking Africa from the global system and developing tolerance towards interethnic and political differences. This approach requires a new kind of moral and political culture, and new structures of political decision-making and accountability that are locally accountable and diversified. [source] Antiproliferative Effect of Furanocoumarins from the Root of Angelica dahurica on Cultured Human Tumor Cell LinesPHYTOTHERAPY RESEARCH, Issue 3 2007Young-Kyoon Kim Abstract A bioassay-guided fractionation of the root extract of Angelica dahurica (Umbelliferae) led to the isolation of six furanocoumarins as active ingredients responsible for the antitumoral property. The hexane soluble part of the extract demonstrated a signicant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nervous system) and HCT-15 (colon) in vitro, whereas the remaining water soluble part exhibited poor inhibition. Intensive investigation of the hexane soluble part of the extract yielded six furanocoumarins, i.e. isoimperatorin, cnidicin, imperatorin, oxypeucedanin, byakangelicol, oxypeucedanin hydrate, all of which exhibited a signicant inhibition on cell proliferation in a dose-dependent manner. Copyright © 2006 John Wiley & Sons, Ltd. [source] Morphology and Anatomy of Shoot, Root, and Propagation Systems in Hoffmannseggia glaucaPLANT BIOLOGY, Issue 6 2007T. A. Kraus Abstract: Hoffmannseggia glauca is a perennial weed that has tubers and root-borne buds. Some authors only consider root tubers without mentioning root-borne buds, while others consider that more anatomic studies become necessary to determine the origin of these structures and to interpret their behaviour. The objectives are: to study the growth form of the plant in order to analyze the ontogeny of its propagation organs, and to study its shoot and root anatomical characters that affect water conductivity. Hoffmannseggia glauca was collected in Argentina. Development of its shoot and root systems was observed. Shoots and roots were processed to obtain histological slides. Macerations were prepared to study vessel members. Primary and lateral roots originate buds that develop shoots at the end of the first year. In winter, aerial parts die and only latent buds at soil surface level and subterranean organs remain. In the following spring, they develop innovation shoots. Roots show localized swellings (tuberous roots), due to a pronounced increase of ray thickness and parenchymatous proliferation in the root center. Root vessel members are wider than those of aerial and subterranean shoots. Early development of an extensive root system, presence of root borne buds, anatomic and physiological specialization of innovation shoots, capability of parenchymatous rays to originate buds and tuberous roots, and high water transport efficiency in subterranean organs lead Hoffmannseggia glauca to display higher colonization potential than other species. [source] Root and stem rot of Schefflera arboricola in Brazil, caused by Fusarium solaniPLANT PATHOLOGY, Issue 6 2001NEW DISEASE REPORT No abstract is available for this article. [source] Armillaria Root Rot: Biology and Control of Honey Fungus.PLANT PATHOLOGY, Issue 3 2001Edited by R. T. V. Fox. No abstract is available for this article. [source] Consequences of soil compaction for seedling establishment: Implications for natural regeneration and restorationAUSTRAL ECOLOGY, Issue 8 2005I. E. BASSETT Abstract Soil compaction can affect seedling root development by decreasing oxygen availability and increasing soil strength. However, little quantitative information is available on the compaction tolerances of non-crop native species. We investigated the effects of soil compaction on establishment and development of two New Zealand native species commonly used in restoration programmes; Cordyline australis (Agavaceae) (cabbage tree) a fleshy rooted species, and Leptospermum scoparium (Myrtaceae) (manuka) a very finely rooted species. Seedlings were grown in a range of soil compaction levels in growth cabinet experiments. Low levels of soil compaction (0.6 MPa) reduced both the number and speed of C. australis seedlings penetrating the soil surface. In contrast, L. scoparium seedlings showed improved establishment at an intermediate compaction level. Root and shoot growth of both species decreased with increasing soil strength, with L. scoparium seedlings tolerating higher soil strengths than did C. australis. Despite these results, soil strength accounted for only a small amount of variation in root length (R2 < 0.25), due to greater variability in growth at low soil strengths. Soil strengths of 0.6 MPa are likely to pose a barrier to C. australis regeneration. This is consistent with adaptation to organic and/or soft, waterlogged soils. Active intervention may be necessary to establish C. australis from seed on many sites previously in farmland. [source] Effect of Elicitation on Growth, Respiration, and Nutrient Uptake of Root and Cell Suspension Cultures of HyoscyamusmuticusBIOTECHNOLOGY PROGRESS, Issue 2 2002Edgard B. Carvalho The elicitation of Hyoscyamus muticus root and cell suspension cultures by fungal elicitor from Rhizoctonia solani causes dramatic changes in respiration, nutrient yields, and growth. Cells and mature root tissues have similar specific oxygen uptake rates (SOUR) before and after the onset of the elicitation process. Cell suspension SOUR were 11 and 18 ,mol O2/g FW·h for non-elicited control and elicited cultures, respectively. Mature root SOUR were 11 and 24 ,mol O2/g FW·h for control and elicited tissue, respectively. Tissue growth is significantly reduced upon the addition of elicitor to these cultures. Inorganic yield remains fairly constant, whereas yield on sugar is reduced from 0.532 to 0.352 g dry biomass per g sugar for roots and 0.614 to 0.440 g dry biomass per g sugar for cells. This reduction in yield results from increased energy requirements for the defense response. Growth reduction is reflected in a reduction in root meristem (tip) SOUR, which decreased from 189 to 70 ,mol O2/g FW·h upon elicitation. Therefore, despite the increase in total respiration, the maximum local oxygen fluxes are reduced as a result of the reduction in metabolic activity at the meristem. This distribution of oxygen uptake throughout the mature tissue could reduce mass transfer requirements during elicited production. However, this was not found to be the case for sesquiterpene elicitation, where production of lubimin and solavetivone were found to increase linearly up to oxygen partial pressures of 40% O2 in air. SOUR is shown to similarly increase in both bubble column and tubular reactors despite severe mass transfer limitations, suggesting the possibility of metabolically induced increases in tissue convective transport during elicitation. [source] Local perspective of the impact of the HIPAA privacy rule on researchCANCER, Issue 2 2006M.P.H., Michael S. Wolf Ph.D. Abstract BACKGROUND The operational and economic impact of the Health Insurance Portability and Accountability Act (HIPAA) of 1996 was evaluated. The setting was a natural experiment which involved a single-site, clinical research study that was initiated before the enactment of HIPAA and subsequently modified to be compliant with the new policy. METHODS A formative assessment was conducted of the recruitment process to a clinical trial evaluating the efficacy of an educational strategy to inform Veterans about the National Cancer Institute/Department of Veterans Affairs cosponsored Selenium and Vitamin E Cancer Prevention Trial (SELECT). Personnel time and costs were determined based on weekly accrual for study periods before and after the implementation of HIPAA. Root cause analysis was used to assess the recruitment protocol and to identify areas for improvement. RESULTS The implementation of HIPAA resulted in a 72.9% decrease in patient accrual (7.0 patients/wk vs. 1.9 patients/wk, P < 0.001), and a threefold increase in mean personnel time spent recruiting (4.1 hrs/patient vs. 14.1 hrs/patient, P < 0.001) and mean recruitment costs ($49/patient vs. $169/patient, P < 0.001). Upon review of the modified HIPAA-compliant protocol, revisions in the recruitment procedure were adopted. The revised protocol improved weekly accrual by 73% (1.9 patients/wk vs. 7.1 patients/wk, P < 0.001) and resulted in improvements in personnel time (5.4 hrs/patient) and recruitment costs ($65/patient). CONCLUSION Enactment of HIPAA initially placed a considerable burden on research time and costs. Establishing HIPAA-compliant recruitment policies can overcome some of these obstacles, although recruitment costs and time are likely to be greater than those observed before HIPAA. Cancer 2006. © 2005 American Cancer Society. [source] Studies on the Physicochemical Properties, Structure and Antitumor Activity of Polysaccharide YhPS-1 from the Root of Cordalis yanhusuo WangCHINESE JOURNAL OF CHEMISTRY, Issue 2 2006Yi-Wen Tao Abstract A polysaccharide named YhPS-1 was isolated from the root of Cordalis yanhusuo Wang and purified by means of gel-permeation chromatography and ionexchange chromatography. Its physicochemical properties, including monosaccharide composition, carbohydrate content, molecular weight and elemental composition, were determined. The structure of YhPS-1 was elucidated by chemical methods along with 1H and 13C NMR spectroscopy ways, such as including two-dimensional HMQC and HMBC experiments. These results show that YhPS-1 possesses a backbone consisting of terminal , -Glcp -(1,, , -Glcp -(1,6), , -Glcp -(1,4) and , -Glcp -(1,4,6). The bioactive assay showed that it could inhibit the growth of Sarcoma 180 and Lewis pulmonary carcinoma implanted in mice. [source] Adaptive drug resistance mediated by root,nodulation,cell division efflux pumpsCLINICAL MICROBIOLOGY AND INFECTION, Issue 2009C. Daniels Abstract Bacterial resistance to antibiotics is a major therapeutic problem. Bacteria use the same mechanisms for developing resistance to antibiotics as they do for developing resistance to biocide compounds present in some cleaning and personal care products. Root,nodulation,cell division (RND) family efflux pumps are a common means of multidrug resistance, and induction of their expression can explain the observed cross-resistance found between antibiotics and biocides in laboratory strains. Hence, there is a relationship between the active chemicals used in household products, organic solvents and antibiotics. The widespread use of biocide-containing modern-day household products may promote the development of microbial resistance and, in particular, cross-resistance to antibiotics. [source] Latest news and product developmentsPRESCRIBER, Issue 3 2007Article first published online: 14 MAR 200 PPIs and hip fracture Treatment with a PPI may increase the risk of hip fracture, with longer use associated with higher risk according to a study in UK patients (J Am Med Assoc 2006;297:2947-53). The case control study compared use of PPIs by 13 556 patients with hip fracture and 135 386 controls in the UK General Practice Research Database. Use of a PPI for more than one year was associated with an increase of 44 per cent in the odds of hip fracture. The risk was higher for longer- term use (59 per cent after four years) and at higher doses (more than doubled with long-term high doses). The mechanism for this possible effect may be impaired calcium absorption associated with hypochlorhydria and reduced bone resorption. CHD NSF Statin prescribing has increased by 30 per cent every year since the publication of the Coronary Heart Disease NSF, the Department of Health says. The estimated number of lives saved attributable to statins had risen to 9700 in 2005. The proportion of patients with acute MI who were given thrombolysis within 30 minutes of admission has increased to 83 per cent. Flu jabs cut pneumonia deaths A US study suggests that flu vaccine protects against death during the flu season in patients admitted with community-acquired pneumonia (Arch Intern Med 2007;167:53-9). Nineteen per cent of patients admitted with pneumonia during the winters of 1999-2003 were known to have been vaccinated against flu. Their risk of death during their hospital stay was 70 per cent lower than that of nonvaccinated individuals. After adjustment for antipneumococcal vaccination and comorbidity, the odds of death were still 39 per cent lower. Model to predict admissions The King's Fund, together with New York University and Health Dialog, has published a model that predicts the risk of emergency hospital admission (see www.kingsfund.org.uk). The model is intended for use by PCTs and draws on data from secondary and primary care to define clinical profiles, allowing patients whose condition is deteriorating to be identified before they need admission. Problem drinking The National Treatment Agency for Substance Misuse (NTA), a special authority within the NHS, has published a critical appraisal of the evidence for various treatments for alcohol problems (www.nta.nhs.uk). The 212-page document estimates that over seven million hazardous or harmful drinkers may benefit from brief interventions by any health workers, and over one million dependent drinkers may benefit from specialist intervention. It concludes that cognitive behavioural approaches to specialist treatment are most effective and that treatment probably accounts for about one-third of improvements made in problem drinking. of patients remained on the same treatment after one year, falling to half at two years and about 40 per cent at three years. Treatment was more frequently stopped for lack of efficacy than for adverse effects. Stopping anti-TNFs Discontinuation of treatment with anti-TNF agents is more common in clinical practice than in clinical trial populations, a French study has found (J Rheumatol 2006;33:2372-5). The retrospective analysis of a single centre's experience of treating 770 patients with etanercept (Enbrel), infliximab (Remicade) or adalimumab (Humira) found that fewer than two-thirds of patients remained on the same treatment after one year, falling to half at two years and about 40 per cent at three years. Treatment was more frequently stopped for lack of efficacy than for adverse effects. There were no statistically significant differences between the three agents but there was a trend for infliximab to be least well tolerated. Generic statin savings The Department of Health has estimated that prescribing simvastatin and pravastatin generically would save £85 million per year. Its analysis of the ,Better care, better value' indicators (see www.productivity.nhs.uk) shows that statin prescribing has increased by 150 per cent in the past five years, with costs totalling £600 million in 2005. The Department says that if every PCT prescribed pravastatin and simvastatin by generic name in only 69 per cent of cases ,the level achieved by the top quarter of trusts ,the savings would be over £85 million a year. Herceptin reporting Press reports of a two-year trial of trastuzumab (Herceptin) were generally accurate in reporting its effectiveness but few reported an increased risk of adverse effects, according to the NHS National Library for Health (www.library.nhs.uk). The Herceptin Adjuvant (HERA) trial (Lancet 2007;369:29-36) found that, after an average follow-up of two years, 3 per cent of women treated with trastuzumab died compared with 5 per cent of controls; estimated three-year survival rates were 92.4 and 89.7 per cent respectively. All four press articles reported these findings accurately, but only two mentioned the increased risk of adverse effects. Updated guidance on CDs The Department of Health has published updated guidance on the strengthened governance requirements for managing controlled drugs, taking into account new regulations that came into force on 1 January (seewww.dh.gov.uk/asset Root/04/14/16/67/04141667.pdf). Statin adherence lowers MI mortality Patients with acute myocar- dial infarction (MI) who take their statins as prescribed are significantly more likely to survive for two to three years than those with low adherence (J Am Med Assoc 2007;297: 177-86). The four-year observational study of 31 455 patients with acute MI found that, compared with those who had taken at least 80 per cent of prescribed daily doses, the risk of death in those with less than 40 per cent adherence was 25 per cent greater over 2.4 years. For individuals with intermediate adherence (40-79 per cent), the risk was 12 per cent greater. Both differences were statistically significant after adjustment for potential confounding factors. The authors believe their finding is explained by differences in adherence rather than healthier behaviour because the excess risk of low adherence was less marked with beta-blockers and not significant for calcium-channel blockers. Improving community medicines management Mental health trusts need to improve medicines management by their community teams and improve information sharing with GPs, the Healthcare Commission has found (www.healthcare commission.org.uk). Its national report revealed limited evidence of pharmacist involvement in community mental health teams, even though 90 per cent of patients were cared for in the community. Only 11 per cent of assertive outreach patients had the tests necessary to ensure safe use of their medicines. Medication reviews found that 46 per cent of patients in mental health trusts and 12 per cent of those in acute trusts were not taking their medication appropriately. The Commission also reported that acute trusts received a complete drug history from GPs for fewer than half of audited patients when they were admitted to hospital, and only 30 per cent of PCTs reported that GPs received adequate information on patients' medicines on discharge. Copyright © 2007 Wiley Interface Ltd [source] Broad Beam Ion Sources for Electrostatic Space Propulsion and Surface Modification Processes: From Roots to Present ApplicationsCONTRIBUTIONS TO PLASMA PHYSICS, Issue 7 2007H. Neumann Abstract Ion thrusters or broad beam ion sources are widely used in electrostatic space propulsion and in high-end surface modification processes. A short historical review of the roots of electric space propulsion is given. In the following, we introduce the electrostatic ion thrusters and broad beam ion sources based on different plasma excitation principles and describe the similarities as well as the differences briefly. Furthermore, an overview on source plasma and ion beam characterisation methods is presented. Apart from that, a beam profile modelling strategy with the help of numerical trajectory codes as basis for a special grid system design is outlined. This modelling represents the basis for the adaptation of a grid system for required technological demands. Examples of model validation demonstrate their reliability. One of the main challenges in improvement of ion beam technologies is the customisation of the ion beam properties, e.g. the ion current density profile for specific demands. Methods of an ex-situ and in-situ beam profile control will be demonstrated. Examples for the use of ion beam technologies in space and on earth , the RIT-10 rescue mission of ESA's satellite Artemis, the RIT-22 for BepiColombo mission and the deposition of multilayer stacks for EUVL (Extreme Ultra Violet Lithography) mask blank application are provided in order to illustrate the potential of plasma-based ion beam sources. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] COMMENTARY: Silver Bullet Junkies and the Codifiers That Love Them: Behavioral Roots Behind a Legacy of Bad Modeling and UseDECISION SCIENCES, Issue 2 2008Elliot Bendoly ABSTRACT As research continues to evolve, it is important to look back with a critical eye on its impact on practice and what is guiding its trajectory into the future. In this work we discuss some of the key behavioral drivers that taken as a whole have made for a less than ideal relationship between research, model development, and use/reliance in practice. From a general public-good perspective, there is an obvious need for academics to take on a greater role of responsibility when it comes to both research and curriculum in an effort to avoid some of the failings that our past work has inevitably encouraged to date. [source] Ecological Theology: Roots in Tradition, Liturgical and Ethical Practice for TodayDIALOG, Issue 3 2003Rosemary Radford Ruether Abstract Often it is claimed that themes occasionally present in Christianity such as anthropocentrism, ecological alienation, and redemption as a world-escaping disembodied immortality, translated directly into large-scale abuse of nature and subsequent ecological crisis. Such a view is too simplistic, however. Instead the present environmental and ecological crisis may be primarily traced to cultural, economic, and technological developments of the last 500 years. Indeed, within Christian monasticism, ecofeminism, covenantal ethics, and cosmic christology, one finds ample resources for the transformation of human attitudes towards nature and a brighter ecological future. [source] | ||||||||||||||||||||||||||||||||||||||||||||||