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Considerable Potential (considerable + potential)
Selected AbstractsDefining the moment of erosion: the principle of thermal consonance timingEARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2005D. M. LawlerArticle first published online: 9 DEC 200 Abstract Geomorphological process research demands quantitative information on erosion and deposition event timing and magnitude, in relation to fluctuations in the suspected driving forces. This paper establishes a new measurement principle , thermal consonance timing (TCT) , which delivers clearer, more continuous and quantitative information on erosion and deposition event magnitude, timing and frequency, to assist understanding of the controlling mechanisms. TCT is based on monitoring the switch from characteristically strong temperature gradients in sediment, to weaker gradients in air or water, which reveals the moment of erosion. The paper (1) derives the TCT principle from soil micrometeorological theory; (2) illustrates initial concept operationalization for field and laboratory use; (3) presents experimental data for simple soil erosion simulations; and (4) discusses initial application of TCT and perifluvial micrometeorology principles in the delivery of timing solutions for two bank erosion events on the River Wharfe, UK, in relation to the hydrograph. River bank thermal regimes respond, as soil temperature and energy balance theory predicts, with strong horizontal thermal gradients (often >1 K cm,1 over 6·8 cm). TCT fixed the timing of two erosion events, the first during inundation, the second 19 h after the discharge peak and 13 h after re-emergence from the flow. This provides rare confirmation of delayed bank retreat, quantifies the time-lag involved, and suggests mass failure processes rather than fluid entrainment. Erosion events can be virtually instantaneous, implying ,catastrophic retreat' rather than ,progressive entrainment'. Considerable potential exists to employ TCT approaches for: validating process models in several geomorphological contexts; assisting process identification and improving discrimination of competing hypotheses of process dominance through high-resolution, simultaneous analysis of erosion and deposition events and driving forces; defining shifting erodibility and erosion thresholds; refining dynamic linkages in event-based sediment budget investigations; and deriving closer approximations to ,true' erosion and deposition rates, especially in self-concealing scour-and-fill systems. Copyright © 2005 John Wiley & Sons, Ltd. [source] Changing Graph Use in Corporate Annual Reports: A Time-Series AnalysisCONTEMPORARY ACCOUNTING RESEARCH, Issue 2 2000VIVIEN A. BEATTIE Abstract Graphs in corporate annual reports form part of a powerfully designed annual report package that offers considerable potential for "impression management." The primary purpose of this paper is to determine whether graph use depends on corporate performance. Time-series analysis, not previously used in the financial graphs literature, allows discretionary changes in graph use by companies to be identified and related to changes in individual companies' corporate performance over time. Based on the prior financial graphs and accounting choice literature, we develop two hypotheses that relate changes in graph use to changes in corporate performance. These hypotheses focus on the aggregate and individual company levels. We base our analysis on the corporate annual reports of 137 top UK companies that were in continued existence during the five-year period from 1988 to 1992. At both the aggregate and individual company levels, we find the decision to use key financial variable (KFV) graphs, the primary graphical choice, to be associated positively with corporate performance measures. This finding is consistent with the manipulation hypothesis - that is, that financial graphs in corporate annual reports are used to "manage" favorably the reader's impression of company performance, and hence that there is a reporting bias. [source] The application of transcranial magnetic stimulation in psychiatry and neurosciences researchACTA PSYCHIATRICA SCANDINAVICA, Issue 5 2002P. B. Fitzgerald Objective:,Over recent years transcranial magnetic stimulation (TMS) has become widely applied in the study of neuropsychiatric disorders. The aim of this article is to review the application of TMS as an investigative tool and as a potential therapeutic modality in psychiatric disorders. Method:,A comprehensive literature review. Results:,When applied as an investigative tool, TMS provides innovative ways to directly study the excitability of the cortex, cortical regional connectivity, the plasticity of brain responses and cognitive functioning in illness and disease states. A number of studies suggest the potential of treatment with TMS in disease states, especially in patients with depression, although difficulties exist with the interpretation of the published literature. Conclusion:,TMS has a considerable role in neuropsychiatric research. It appears to have considerable potential as a therapeutic tool in depression, and perhaps a role in several other disorders, although widespread application requires larger trials and establishment of sustained response. [source] Clinical supervision in the alcohol and other drugs field: an imperative or an option?DRUG AND ALCOHOL REVIEW, Issue 3 2007ANN M. ROCHE Abstract There is a growing interest in Clinical Supervision (CS) as a central workforce development (WFD) strategy. This paper provides a definition of and rationale for CS, characterises its various forms, identifies selection and training issues, and advises on policy and implementation issues central to redressing shortcomings in supervision practice within the alcohol and other drugs (AOD) field. Relevant selective literature is reviewed. Key conceptual issues were identified, and strategies developed to address implementation barriers and facilitate relevant policy. There is a common conceptual confusion between administrative supervision and CS. Clarification of the role, function and implementation of CS is required. Priority issues for the AOD field include: enhancing belief in CS; ensuring adequate resource allocation; developing evaluation protocols; and addressing specific arrangements under which supervision should occur. CS has been underutilised to date but holds considerable potential as a WFD strategy. It is fundamental to workers' professional development, can contribute to worker satisfaction and retention, and may improve client outcomes. Critical next steps are to establish the generalisability to the AOD field of the benefits observed from CS in other disciplines, and evaluate longer-term gains of CS programs. [source] Bacterial protein kinase inhibitorsDRUG DEVELOPMENT RESEARCH, Issue 3 2010Michio Kurosu Abstract Protein kinases have become the second most important group of drug targets for the pharmaceutical industry next to G-protein-coupled receptors. Thus, over the past decade, a significant number of small molecules have been generated for protein kinase drug optimization programs. The vast majority of kinase inhibitors target the ATP binding site of the enzyme; however, the poor protein kinase selectivity of ATP-competitive protein kinase inhibitors (PKIs) limits their use for treating chronic diseases. In contrast, for inhibitors of bacterial signal transduction systems targeting bacterial kinase(s), there are no such selectivity requirements as long as the inhibitor does not act on any human kinases at the effective concentrations for killing bacteria in vivo. Protein phosphorylation in bacteria is performed by two-component signal transduction systems (2CSTSs) and eukaryotic-like serine/threonine kinases or bacterial tyrosine kinases. Recently, a large number of studies of protein kinases essential for sustaining bacterial growth and kinases required for virulence have been reported. Thus, bacterial protein kinases offer considerable potential as new drug targets. To identify bacterial PKIs, large chemical libraries of ATP-competitive inhibitors developed for eukaryotic protein kinases are an invaluable asset. This manuscript reviews progress on the development of prokaryotic protein kinase inhibitors. Drug Dev Res 2010. © 2010 Wiley-Liss, Inc. [source] Sediment transmission and storage: the implications for reconstructing landform developmentEARTH SURFACE PROCESSES AND LANDFORMS, Issue 1 2010R. C. Chiverrell Abstract The late Holocene (last 3000 years) development of the lower Ribble valley (northwest England) displays evidence for a complex response to a sediment recharge event forced by land-use change induced increases in erosion and sediment delivery. The deposition of fluvial sediments during the late Holocene was restricted to a series of reaches or depocenters separated by zones with no sediment accumulation constrained by older glacial and fluvial terrain. Apparent reach-wide correlations of fluvial terraces break down under the scrutiny applied by comprehensive and extensive radiocarbon control. Bayesian testing of relative order models show that large-scale geomorphological changes, e.g. the progression from one terrace level to another, were time transgressive between different depocenters. The different histories of sediment delivery and storage are probably a function of local- and process-scale variations in these depocenters, and reflect (dis)connectivity relationships within a reach in propagating a basin-scale change (superslug) in the sediment regime. Disconnectivity in the depositional regime through a fluvial reach limits what we can reconstruct in terms of sediment budgets, but radiocarbon dating of multiple palaeochannels offers considerable potential for landform-based research to uncover rates of change within individual depocenters. Copyright © 2009 John Wiley & Sons, Ltd. [source] Concentrated flow erosion rates reduced through biological geotextilesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2009T. Smets Abstract Soil erosion by concentrated flow can cause serious environmental damage. Erosion-control geotextiles have considerable potential for reducing concentrated flow erosion. However, limited data are available on the erosion-reducing potential of geotextiles. In this study, the effectiveness of three biological geotextiles in reducing soil losses during concentrated flow is investigated. Hereto, runoff was simulated in a concentrated flow flume, filled with an erodible sandy loam on three slope gradients (13·5, 27·0 and 41·5%). Treatments included three biological geotextiles (borassus, buriti and bamboo) and one bare soil surface. Darcy,Weisbach friction coefficients ranged from 0·01 to 2·84. The highest values are observed for borassus covered soil surfaces, followed by buriti, bamboo and bare soil, respectively. The friction coefficients are linearly correlated with geotextile thickness. For the specific experimental conditions of this study, borassus geotextiles reduced soil detachment rate on average to 56%, buriti geotextiles to 59% and bamboo geotextiles to 66% of the soil detachment rate for bare soil surfaces. Total flow shear stress was the hydraulic parameter best predicting soil detachment rate for bare and geotextile covered surfaces (R2 = 0·75,0·84, p <0·001, n = 12,15). The highest resistance against soil detachment was observed for the borassus covered soil surfaces, followed by buriti, bamboo and bare soil surfaces, respectively. Overall, biological geotextiles are less effective in controlling concentrated flow erosion compared with interrill erosion. Copyright © 2009 John Wiley & Sons, Ltd. [source] Microautosamplers for discrete sample injection and dispensationELECTROPHORESIS, Issue 9 2005Chun-Wei Huang Abstract Microfluidic systems show considerable potential for use in the continuous reaction and analysis of biosamples for various applications, such as drug screening and chemical synthesis. Typically, microfluidic chips are externally connected with large-scale autosamplers to inject specific volumes of discrete samples in the continuous monitoring and analysis of multiple samples. This paper presents a novel microelectromechanical system (MEMS)-based autosampler capable of performing the discrete injection and dispensation of variable-volume samples. This microdevice can be integrated with other microfluidic devices to facilitate the continuous monitoring and analysis of multiple biosamples. By means of electroosmotic focusing and switching controlled by the direct application of electric sources on specific fluid reservoirs, a precise sample volume can be injected into the specified outlet port. Fluorescence dye images verify the performance of the developed device. An injection-and-washing scheme is developed to prevent cross-contamination during the continuous injection of different samples. This approach renders feasible the injection of several discrete samples using a single microchip. Compared to its large-scale counterparts, the developed microautosampler is compact in size, has low fabrication costs, is straightforward to control, and most importantly, is readily integrated with other microfluidic devices (e.g., microcapillary electrophoresis chips) to form a microfluidic system capable of the continuous monitoring and analysis of bioreactions. The proposed microautosampler could be promising towards realizing the micrototal analysis system (,-TAS) concept. [source] A novel microfluidic mixer utilizing electrokinetic driving forces under low switching frequencyELECTROPHORESIS, Issue 9 2005Lung-Ming Fu Abstract This paper presents a novel technique in which low-frequency periodic electrokinetic driving forces are utilized to mix electrolytic fluid samples rapidly and efficiently in a double-T-form microfluidic mixer. Without using any additional equipment to induce flow perturbations, only a single high-voltage power source is required for simultaneously driving and mixing the sample fluids which results in a simple and low-cost system for the mixing purpose. The effectiveness of the mixer as a function of the applied electric field and the periodic switching frequency is characterized by the intensity distribution calculated downstream from the mixing zone. The present numerical and experimental results confirm that the proposed double-T-form micromixer has excellent mixing capabilities. The mixing efficiency can be as high as 95% within a mixing length of 1000 ,m downstream from the secondary T-junction when a 100 V/cm driving electric field strength and a 2 Hz periodic switching frequency are applied. The results reveal that the optimal switching frequency depends upon the magnitude of the main applied electrical field. The rapid double-T-form microfluidic mixer using the periodic driving voltage switching model proposed in this study has considerable potential for use in lab-on-a-chip systems. [source] A porous-matrix sensor to measure the matric potential of soil water in the fieldEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 1 2007W. R. Whalley Summary The matric potential of soil water is probably the most useful assessment of soil water status. However, the water-filled tensiometer (the benchmark instrument for measuring matric potential) typically only operates in the range 0 to ,85 kPa. In this paper, we report the development of a porous-matrix sensor to measure matric potential in the approximate range ,50 to ,300 kPa. The sensor uses a dielectric probe to measure the water content of a ceramic material with known water retention characteristics. The calculation of matric potential takes into account hysteresis through the application of an appropriate model to measured wetting and drying loops. It is important that this model uses closed, rather than open, scanning loops. The calibrated sensors were tested in the field and the output compared with data from water-filled tensiometers and dielectric measurements of soil water content. These comparisons indicated that conventional tensiometers gave stable but false readings of matric potential when soil dried to matric potentials more negative than ,80 kPa. The porous-matrix sensors appeared to give reliable readings of matric potential in soil down to ,300 kPa and also responded appropriately to repeated wetting and drying. This porous-matrix sensor has considerable potential to help understand plant responses to drying soil. [source] Methods for the isolation and identification of Listeria spp. and Listeria monocytogenes: a reviewFEMS MICROBIOLOGY REVIEWS, Issue 5 2005Uta Gasanov Abstract Listeria monocytogenes is an important food-borne pathogen and is widely tested for in food, environmental and clinical samples. Identification traditionally involved culture methods based on selective enrichment and plating followed by the characterization of Listeria spp. based on colony morphology, sugar fermentation and haemolytic properties. These methods are the gold standard; but they are lengthy and may not be suitable for testing of foods with short shelf lives. As a result more rapid tests were developed based on antibodies (ELISA) or molecular techniques (PCR or DNA hybridization). While these tests possess equal sensitivity, they are rapid and allow testing to be completed within 48 h. More recently, molecular methods were developed that target RNA rather than DNA, such as RT-PCR, real time PCR or nucleic acid based sequence amplification (NASBA). These tests not only provide a measure of cell viability but they can also be used for quantitative analysis. In addition, a variety of tests are available for sub-species characterization, which are particularly useful in epidemiological investigations. Early typing methods differentiated isolates based on phenotypic markers, such as multilocus enzyme electrophoresis, phage typing and serotyping. These phenotypic typing methods are being replaced by molecular tests, which reflect genetic relationships between isolates and are more accurate. These new methods are currently mainly used in research but their considerable potential for routine testing in the future cannot be overlooked. [source] Identification of Atlantic bluefin tuna (Thunnus thynnus) stocks from putative nurseries using otolith chemistryFISHERIES OCEANOGRAPHY, Issue 2 2003Jay R. Rooker Abstract Chemical signatures in the otoliths of teleost fishes represent natural tags that may reflect differences in the chemical and physical characteristics of an individuals' environment. Otolith chemistry of Atlantic bluefin tuna (Thunnus thynnus) was quantified to assess the feasibility of using these natural tags to discriminate juveniles (age 0 and age 1) from putative nurseries. A suite of six elements (Li, Mg, Ca, Mn, Sr and Ba) was measured in whole otoliths using solution-based inductively coupled plasma mass spectrometry. Otolith chemistry of age-1 T. thynnus collected from the two primary nurseries in the Mediterranean Sea and western Atlantic Ocean differed significantly, with a cross-validated classification accuracy of 85%. Spatial and temporal variation in otolith chemistry was evaluated for age-0 T. thynnus collected from three nurseries within the Mediterranean Sea: Alboran Sea (Spain), Ligurian Sea (northern Italy), and Tyrrhenian Sea (southern Italy). Distinct differences in otolith chemistry were detected among Mediterranean nurseries and classification accuracies ranged from 62 to 80%. Interannual trends in otolith chemistry were observed between year classes of age-0 T. thynnus in the Alboran Sea; however, no differences were detected between year classes in the Tyrrhenian Sea. Age-0 and age-1 T. thynnus collected from the same region (Ligurian Sea) were also compared and distinct differences in otolith chemistry were observed, indicating ontogenetic shifts in habitat or elemental discrimination. Findings suggest that otolith chemistry of juvenile T. thynnus from different nurseries are distinct and chemical signatures show some degree of temporal persistence, indicating the technique has considerable potential for use in future assessments of population connectivity and stock structure of T. thynnus. [source] Transistor Paint: Environmentally Stable N -alkyldithienopyrrole and Bithiazole-Based Copolymer Thin-Film Transistors Show Reproducible High Mobilities without AnnealingADVANCED FUNCTIONAL MATERIALS, Issue 21 2009Junying Liu Abstract New solution processable 4-(2-hexyldecan)- 4H -bisthieno[2,3- d:3,,2,- b]pyrrole and 4,4,-dialkyl-2,2,-bithiazole-based copolymers (PBTzDTPs) are synthesized with excellent FET performance. These novel copolymers have considerable potential in printable electronics as they have high charge carrier mobilities, excellent air stability, good solution processibility, and no requirement for post-deposition thermal annealing, all requirements for this field of application. The thin film transistors fabricated from PBTzDTPs achieve field effect mobilities as high as 0.14,cm2 V,1 s,1 with current on/off ratios up to 106 without thermal annealing. In addition, the devices exhibit stable performance in air, showing no significant degradation over 60 days. Moreover, the polymers described here provide an excellent example of the systems in which higher mobility performance does not require higher crystalline, long-range ordered structures. Such a system appears to be particularly promising for rapid fabrication techniques, where kinetic conditions usually prevent the development of long-range order. [source] Efficient Luminescence from Rare-Earth Fluoride Nanoparticles with Optically Functional Shells,ADVANCED FUNCTIONAL MATERIALS, Issue 7 2006M. Lezhnina Abstract Rare-earth fluorides are a class of materials with considerable potential in optical applications. Fluoride lattices typically permit high coordination numbers for the hosted rare-earth ions, and the high ionicity of the rare-earth-to-fluorine bond leads to a wide bandgap and very low vibrational energies. These factors make rare-earth fluorides very useful in optical applications employing vacuum ultraviolet and near-infrared excitation. The preparation of nanometer-sized particles has opened the door for new properties and devices if the performance of their macroscopic counterparts can be conserved in the nanometer regime. However, at small particle sizes, defect surface states and adhering water reduce the optical efficiency. These shortcomings can be reduced by applying protective shells around the luminescent cores, which can also be involved in the luminescent process. [source] Impurity Doping in Silicon NanowiresADVANCED MATERIALS, Issue 27 2009Naoki Fukata Abstract Silicon nanowires (SiNWs) have considerable potential to assist the realization of next-generation metal-oxide semiconductor field-effect transistors (MOSFETs) with vertical structures. Impurity doping and its control is a key technique in the creation of SiNW devices, which renders it necessary to develop characterization methods for dopant atoms in SiNWs. In this Research News, we described how the states of the dopant atoms boron and phosphorus can be detected. [source] Young People, Photography and EngagementINTERNATIONAL JOURNAL OF ART & DESIGN EDUCATION, Issue 2 2003Nick Stanley Over ten years research into photography and education has been undertaken at Birmingham Institute of Art and Design in collaboration with the Arts Council of England, West Midlands Arts, and local community photography agencies. A range of case studies were undertaken to explore how young people used photography, particularly in self-empowerment. These ranged from students in Further Education challenging concepts of visual stereotypes of disability, young lesbian, gay and bisexual people constructing their own website, and individuals and groups creating and modifying their own images in a shopping centre. A democratic action research methodology was developed to enable the young people to establish their own agenda and generate standards for evaluating their work. A particular feature of the later research was a self-reflective journal that was shared between the researcher and everyone engaged in the project. This resource has considerable potential in photography and elsewhere in art and design education. [source] Thermographic assessment of tumor growth in mouse xenograftsINTERNATIONAL JOURNAL OF CANCER, Issue 5 2007Chengli Song Abstract In human breast tumors, a 1,2°C increase in skin surface temperature is usually observed at the periphery; it has been proposed that this change is due to the hypervascularity and increased blood flow resulting from tumor-associated angiogenesis. Here we tested the hypothesis that thermal imaging might represent a useful adjunctive technique in monitoring the growth dynamics of human tumor xenografts. Xenografts were established in immunocomprised nude mice using MDA-MB-231 or MCF7 breast cancer cells. We exploited the inherent noncontact and noninvasive advantages of infrared thermography to detect skin surface temperature changes. Continuous thermographic investigation was performed to detect and monitor tumor growth in vivo and high resolution digital images were analyzed to measure the tumor temperature dynamics. In contrast to the skin temperature increases associated with human breast cancer, a consistent temperature decrease was found in the xenograft mice. In one case, a smaller secondary tumor, otherwise undetectable, was clearly evident by thermal imaging. The tumors were cooler than the surrounding tissue with a maximum temperature reduction of 1.5°C for MDA-MB-231 tumor and 3°C for MCF7 tumors observed on day 14. In addition, the temperature of the xenograft tumors decreased progressively as they grew throughout the observation period. It was demonstrated that thermographic imaging could detect temperature changes as small as 0.1°C on the skin surface at an early stage of tumor development. The findings of the study indicate that thermographic imaging might have considerable potential in monitoring human tumor xenografts and their response to anticancer drugs. © 2007 Wiley-Liss, Inc. [source] The Sino,Russian Partnership and U.S. Policy Toward North Korea: From Hegemony to Concert in Northeast AsiaINTERNATIONAL STUDIES QUARTERLY, Issue 3 2005David Kerr This paper presents two sets of arguments: one theoretical and one analytical. The theoretical arguments concern the relationship between regional ordering and systemic change. The paper questions the usefulness of the unipolar conception of the contemporary system arguing that the interaction of the Great Powers cannot be understood without reference to regional dynamics. Thus, a unipolar system implies considerable potential for U.S. hegemonic intervention at the regional level but in East Asia, we find an equilibrium constructed out of both material and normative forces, defined as a concert, which presents a considerable restraint on all powers, including the U.S. The paper then proceeds to examine these claims through an analysis of the foreign policies of the U.S., Russia, and China over the North Korean nuclear problem that emerged after 2002. It finds that China and Russia have substantive common interests arising from internal and external re-ordering in which they look to strategic partnerships, regional multilateralism, and systemic multipolarization as inter-locking processes. The paper finds that they have collaborated over the Korean crisis to prevent a U.S. unilateral solution but that this should not be construed as a success for an open counterhegemonic strategy as it was only under the constraining conditions of East Asian concert, including the dynamics within the U.S. alliance systems, that this collaboration was successful. Nevertheless, the paper concludes that regional multipolarity and systemic unipolarity are contradictory: a system that exhibits multipolarization at the regional level cannot be characterized as unipolar at the global level. [source] Epistatic kinship a new measure of genetic diversity for short-term phylogenetic structures , theoretical investigationsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 3 2006C. Flury Summary The epistatic kinship describes the probability that chromosomal segments of length x in Morgan are identical by descent. It is an extension from the single locus consideration of the kinship coefficient to chromosomal segments. The parameter reflects the number of meioses separating individuals or populations. Hence it is suggested as a measure to quantify the genetic distance of subpopulations that have been separated only few generations ago. Algorithms for the epistatic kinship and the extension of the rules to set up the rectangular relationship matrix are presented. The properties of the epistatic kinship based on pedigree information were investigated theoretically. Pedigree data are often missing for small livestock populations. Therefore, an approach to estimate epistatic kinship based on molecular marker data are suggested. For the epistatic kinship based on marker information haplotypes are relevant. An easy and fast method that derives haplotypes and the respective frequencies without pedigree information was derived based on sampled full-sib pairs. Different parameters of the sampling scheme were tested in a simulation study. The power of the method decreases with increasing segment length and with increasing number of segments genotyped. Further, it is shown that the efficiency of the approach is influenced by the number of animals genotyped and the polymorphism of the markers. It is discussed that the suggested method has a considerable potential to allow a phylogenetic differentiation between close populations, where small sample size can be balanced by the number, the length, and the degree of polymorphism of the chromosome segments considered. [source] Using Soft Systems Methodology for Performance Improvement and Organisational Change in the English National Health ServiceJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 4 2004Brian Jacobs The Soft Systems Methodology (SSM) advocated by Checkland and Scholes (1990) has considerable potential. It can provide policy makers, professionals, and managers in complex health organisations with a valuable addition to management approaches leading to practical improvements through innovative organisational change. With reference to the English National Health Service (NHS), this author argues that SSM can enable managers and others to address problem situations holistically, identify critical issues, and reach an accommodation of different viewpoints as a basis for improvement. The SSM approach can usefully compliment strategic frameworks, such as the Balanced Scorecard, in achieving clarity of thinking about performance and change issues'. [source] Hair colouring, permanent styling and hair structureJOURNAL OF COSMETIC DERMATOLOGY, Issue 3-4 2003S Harrison Summary Hair is an important component of body image and has immense psychological importance for both men and women. Women, in particular, over the ages have modified their appearance through changing their hair colour or style. Hair can be straight, wavy or curly, blonde, black, brown or red. These natural variations are an important part of our identity that can be manipulated according to the dictates of fashion, culture or society. Different types of hair have varying affinity for the different colouring and waving methods. Damaged hair also has a different affinity for hair products than normal healthy hair. The hair shaft is remarkably strong and resistant to the extremes of nature. Hair cosmetics are widely available and manipulate the structural properties of hair. Whilst most procedures are safe, there is considerable potential for damage to the hair and hair problems of acute onset, including hair breakage, hair loss and loss of condition, are frequently blamed on the last product used on the hair. Hair problems are particularly prevalent among people who repeatedly alter the natural style of their hair. [source] Synthesis of 3H and fluorescence-labelled poly (DL -Lactic acid)JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 10 2001S. Ponsart Abstract The novel polymer modification method based on the activation of an aliphatic polyester chain by using lithium diisopropylamide at low temperature to form a polycarbanion bearing nucleophilic sites in a position , to the carbonyl groups was applied to rac -poly (lactic acid), PLA50, to label this polymer with radioactive tritium atoms or with a fluorescent dye. Despite simultaneous partial chain degradation, radioactive PLA50 and fluorescent PLA50 with Mn=14000 g mol,1, Mw/Mn=1.9 and Mn=32 000 g mol,1, Mw/Mn=2.4, respectively, were obtained. The specific activity of the final compound was 3.7 µCi g,1 that squared with 0.3, substitution reaction. The fluorescent polymer was substituted with 0.25% ratio. This work shows that the LDA activation method appears to have considerable potential. Copyright © 2001 John Wiley & Sons, Ltd. [source] Emerging drugs: mechanism of action, mass spectrometry and doping control analysisJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 4 2009Mario Thevis Abstract The number of compounds and doping methods in sports is in a state of constant flux. In addition to ,traditional' doping agents, such as anabolic androgenic steroids or erythropoietin, new therapeutics and emerging drugs have considerable potential for misuse in elite sport. Such compounds are commonly based on new chemical structures, and the mechanisms underlying their modes of action represent new therapeutic approaches arising from recent advances in medical research; therefore, sports drug testing procedures need to be continuously modified and complementary methods developed, preferably based on mass spectrometry, to enable comprehensive doping controls. This tutorial not only discusses emerging drugs that can be categorized as anabolic agents (selective androgen receptor modulators, SARMs), gene doping [hypoxia-inducible factor stabilizers, peroxisome-proliferator-activated receptor (PPAR),-agonists] and erythropoietin-mimetics (Hematide) but also compounds with potentially performance-enhancing properties that are not classified in the current list of the World Anti-Doping Agency. Compounds such as ryanodine-calstabin-complex modulators (benzothiazepines) are included, their mass spectrometric properties discussed, and current approaches in sports drug testing outlined. Copyright © 2009 John Wiley & Sons, Ltd. [source] Chemomechanical caries removal in primary teeth in a group of anxious childrenJOURNAL OF ORAL REHABILITATION, Issue 8 2003G. Ansari summary Chemomechanical removal of dental caries has considerable potential in the treatment of patients with management problems, especially in paediatric dentistry. The aim of this study was to assess the acceptance and success of the technique in young nervous patients. A group of 20 patients, aged between 4 and 10 years with a high level of dental anxiety was selected. The study achieved a success rate of over 90% in acceptance of cavity preparation by this procedure followed by placement of a restoration. The length of time required for cavity preparation was comparable with conventional methods. The need for local anaesthesia was reduced or eliminated and the children did not complain of any pain during the procedure. It is concluded that chemomechanical caries removal in vivo in primary teeth is an effective alternative to conventional mechanical caries removal and is advantageous in patients who have a phobia to the dental handpiece and/or injections. [source] AFLP Analysis of Trichoderma spp. from India Compared with Sequence and Morphological-based DiagnosticsJOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2005H. K. Buhariwalla Abstract Trichoderma species offer considerable potential for controlling aflatoxin contamination in groundnut and other crops. Initial classification of 48 Trichoderma isolates, derived from four different groundnut cultivation sites in India was based on alignment of 28S rDNA sequences to GenBank sequences of ex-type strains. This was found to be substantially more reliable than our routine morphological characterization, but did not provide a comprehensive diagnostic solution, as unique single nucleotide polymorphism (SNP) haplotypes could not be identified for all species. However, all the Trichoderma isolates could be readily distinguished by amplified fragment length polymorphism (AFLP) analysis, based on six primer pair combinations, which generated 234 polymorphic bands. In addition, individual AFLP bands were identified which differentiate closely related species. Similarly, AFLP bands were identified that correlated with different types of antagonism to Aspergillus flavus. The implications of these results for the development of simple polymerase chain reaction (PCR)-based diagnostic assays for antagonistic isolates of Trichoderma is discussed. [source] Benzene polycarboxylic acids,A ubiquitous class of compounds in soilsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 5 2010Ludwig Haumaier Abstract Black carbon (BC) occurs ubiquitously in the environment. Its oxidation in the laboratory yields a suite of benzene polycarboxylic acids (BPCAs), suggesting similar oxidation products in soils. Since only for a few soils the occurrence of BPCAs in the free form has been documented, screening for them in a broad range of contrasting soils was conducted. They were extracted from soil samples with 0.5 M NaOH and quantified using gas chromatography,mass spectrometry. As expected, BPCAs turned out to be as ubiquitous as BC. They were detected not only in every soil sample investigated so far, but also in samples from drill cores up to a depth of 10 m and in recently deposited calcareous tufa. The concentrations covered a range similar to that of some phenolic acids. The range exceeded those reported for low-molecular-weight aliphatic acids or simple sugars in soils. The distribution of BPCAs in soil profiles indicated a considerable potential of translocation within, and export from, soil, in particular of benzene hexacarboxylic (mellitic) acid. Mellitic acid may therefore be present in almost any geochemical sample affected by seepage water from soils. Its high water solubility and strong metal-complexing ability suggest it may be involved in metal-transport processes, at least on geological timescales. [source] Fossil testate amoebae in coastal deposits in the UK: implications for studies of sea-level changeJOURNAL OF QUATERNARY SCIENCE, Issue 5-6 2002Helen M. Roe Abstract Assemblages of testate amoebae in UK saltmarshes are strongly correlated with elevation and flooding duration, suggesting that if adequately preserved in sediments they may be used as accurate sea-level indicators. To examine the preservation of testate amoebae in the fossil record in coastal environments, subsamples were collected from a range of coastal sites around Britain, including saltmarsh, coastal reedswamp, isolation basin, back-barrier and coastal raised bog sites. The results showed that testate amoebae are present in the fossil record, although in variarble species diversities, concentrations and states of preservation. Testate amoebae were found to be well preserved in isolation basin infills and coastal raised bog deposits, where diverse assemblages (>20 taxa) were recorded. In the upper part of the isolation basin sequence from Loch nan Corr, northwest Scotland, the testate amoebae assemblages showed a greater degree of sensitivity to transitional salinity changes than existing foraminferal and larger testate amoebae data sets. This implies that testate amoebae, particularly small to medium-sized specimens (15,300 µm), may hold considerable potential for sea-level reconstruction in these environments. Preservation of testate amoebae in a freshly sampled core of saltmarsh sediment from South Wales was reasonable, although test distribution decreased significantly in abundance below 18 cm. The assemblage composition was similar to that found in the contemporary surface environment. The preservation of testate amoebae in saltmarsh and coastal reedswamp deposits of mid-Holocene age was variable and generally poor. Partial dehydration of the sediment samples may account for this. Further studies are required to examine the palaeoecology and distribution of testate amoebae in similar coastal settings, to strengthen these preliminary findings. Copyright © 2002 John Wiley & Sons, Ltd. [source] Simultaneous modelling of multiple traffic safety performance indicators by using a multivariate generalized linear mixed modelJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 3 2004Trevor C. Bailey Summary., Traffic safety in the UK is one of the increasing number of areas where central government sets targets based on ,outcome-focused' performance indicators (PIs). Judgments about such PIs are often based solely on rankings of raw indicators and simple league tables dominate centrally published analyses. There is a considerable statistical literature examining health and education issues which has tended to use the generalized linear mixed model (GLMM) to address variability in the data when drawing inferences about relative performance from headline PIs. This methodology could obviously be applied in contexts such as traffic safety. However, when such models are applied to the fairly crude data sets that are currently available, the interval estimates generated, e.g. in respect of rankings, are often too broad to allow much real differentiation between the traffic safety performance of the units that are being considered. Such results sit uncomfortably with the ethos of ,performance management' and raise the question of whether the inference from such data sets about relative performance can be improved in some way. Motivated by consideration of a set of nine road safety performance indicators measured on English local authorities in the year 2000, the paper considers methods to strengthen the weak inference that is obtained from GLMMs of individual indicators by simultaneous, multivariate modelling of a range of related indicators. The correlation structure between indicators is used to reduce the uncertainty that is associated with rankings of any one of the individual indicators. The results demonstrate that credible intervals can be substantially narrowed by the use of the multivariate GLMM approach and that multivariate modelling of multiple PIs may therefore have considerable potential for introducing more robust and realistic assessments of differential performance in some contexts. [source] Modelling cell generation times by using the tempered stable distributionJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 4 2008Karen J. Palmer Summary., We show that the family of tempered stable distributions has considerable potential for modelling cell generation time data. Several real examples illustrate how these distributions can improve on currently assumed models, including the gamma and inverse Gaussian distributions which arise as special cases. Our applications concentrate on the generation times of oligodendrocyte progenitor cells and the yeast Saccharomyces cerevisiae. Numerical inversion of the Laplace transform of the probability density function provides fast and accurate approximations to the tempered stable density, for which no closed form generally exists. We also show how the asymptotic population growth rate is easily calculated under a tempered stable model. [source] Flaxseed as a functional food source,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2001B Dave Oomah Abstract Flaxseed is emerging as one of the key sources of phytochemicals in the functional food arena. In addition to being one of the richest sources of ,-linolenic acid oil and lignans, flaxseed is an essential source of high-quality protein and soluble fibre and has considerable potential as a source of phenolic compounds. The implications of diets containing flaxseed or its components for human nutrition and disease prevention are analysed in this paper. Results of the first meta-analysis examining the relationship between intake of flaxseed or its components and risk reduction of disease in humans is presented. Some areas of potential opportunities and impact of using flaxseed or its components in the diet are highlighted. For the Department of Agriculture and Agri-Food, Government of Canada. © Minister of Public Works and Government Services Canada 2001. Published for SCI by John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||