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Significant Potential (significant + potential)
Selected AbstractsUse tests: ROAT (repeated open application test)/PUT (provocative use test): an overviewCONTACT DERMATITIS, Issue 1 2000Tokio Nakada As one step in defining the clinical relevance of exposure to an allergen identified with patch testing, use tests (provocative use test (PUT), and repeated open application test (ROAT)) have been used. In 1/2 of the cases of seemingly reliable patch tests, use tests are negative, suggesting that the patient's biologic threshold of response had not been reached with open application dosing. Dramatic differences exist in regional skin reactivity and percutaneous penetration. Negative results of use tests on normal skin may become positive on diseased skin. To refine this assay further, more controlled observations and analysis of reaction differences between normal and damaged skin, and among regional anatomic sites might be performed. In addition, we require a standardized measurement for the results. Use testing has significant potential in refinement of the evidence-based diagnosis of clinical relevance. However, for general validation, we should fill the deficiencies described above. [source] A Single Ventilator for Multiple Simulated Patients to Meet Disaster SurgeACADEMIC EMERGENCY MEDICINE, Issue 11 2006Greg Neyman MD Objectives To determine if a ventilator available in an emergency department could quickly be modified to provide ventilation for four adults simultaneously. Methods Using lung simulators, readily available plastic tubing, and ventilators (840 Series Ventilator; Puritan-Bennett), human lung simulators were added in parallel until the ventilator was ventilating the equivalent of four adults. Data collected included peak pressure, positive end-expiratory pressure, total tidal volume, and total minute ventilation. Any obvious asymmetry in the delivery of gas to the lung simulators was also documented. The ventilator was run for almost 12 consecutive hours (5.5 hours of pressure control and more than six hours of volume control). Results Using readily available plastic tubing set up to minimize dead space volume, the four lung simulators were easily ventilated for 12 hours using one ventilator. In pressure control (set at 25 mm H2O), the mean tidal volume was 1,884 mL (approximately 471 mL/lung simulator) with an average minute ventilation of 30.2 L/min (or 7.5 L/min/lung simulator). In volume control (set at 2 L), the mean peak pressure was 28 cm H2O and the minute ventilation was 32.5 L/min total (8.1 L/min/lung simulator). Conclusions A single ventilator may be quickly modified to ventilate four simulated adults for a limited time. The volumes delivered in this simulation should be able to sustain four 70-kg individuals. While further study is necessary, this pilot study suggests significant potential for the expanded use of a single ventilator during cases of disaster surge involving multiple casualties with respiratory failure. [source] Designing new institutions for implementing integrated disaster risk management: key elements and future directionsDISASTERS, Issue 4 2007Chennat Gopalakrishnan The goal of integrated disaster risk management is to promote an overall improvement in the quality of safety and security in a region, city or community at disaster risk. This paper presents the case for a thorough overhaul of the institutional component of integrated disaster risk management. A review of disaster management institutions in the United States indicates significant weaknesses in their ability to contribute effectively to the implementation of integrated disaster risk management. Our analysis and findings identify eight key elements for the design of dynamic new disaster management institutions. Six specific approaches are suggested for incorporating the identified key elements in building new institutions that would have significant potential for enhancing the effective implementation of integrated disaster risk management. We have developed a possible blueprint for effective design and construction of efficient, sustainable and functional disaster management institutions. [source] Spectral analysis and design approach for high force-to-volume extrusion damper-based structural energy dissipationEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 2 2008Geoffrey W. Rodgers Abstract High force-to-volume extrusion damping devices can offer significant energy dissipation directly in structural connections and significantly reduce seismic response. Realistic force levels up to 400,kN have been obtained experimentally validating this overall concept. This paper develops spectral-based design equations for their application. Response spectra analysis for multiple, probabilistically scaled earthquake suites are used to delineate the response reductions due to added extrusion damping. Representative statistics and damping reduction factors are utilized to characterize the modified response in a form suitable for current performance-based design methods. Multiple equation regression analysis is used to characterize reduction factors in the constant acceleration, constant velocity, and constant displacement regions of the response spectra. With peak device forces of 10% of structural weight, peak damping reduction factors in the constant displacement region of the spectra are approximately 6.5,×, 4.0,×, and 2.8,× for the low, medium, and high suites, respectively. At T,=,1,s, these values are approximately 3.6,×, 1.8,×, and 1.4,×, respectively. The maximum systematic bias introduced by using empirical equations to approximate damping reduction factors in design analyses is within the range of +10 to ,20%. The seismic demand spectrum approach is shown to be conservative across a majority of the spectrum, except for large added damping between T,=,0.8 and 3.5,s, where it slightly underestimates the demand up to a maximum of approximately 10%. Overall, the analysis shows that these devices have significant potential to reduce seismic response and damage at validated prototype device force levels. Copyright © 2007 John Wiley & Sons, Ltd. [source] An investigation of the hydrological requirements of River Red Gum (Eucalyptus camaldulensis) Forest, using Classification and Regression Tree modellingECOHYDROLOGY, Issue 2 2009Li Wen Abstract River Red Gum (Eucalyptus camaldulensis) is widely distributed throughout many water courses and floodplains within inland Australia. In recent years, accelerated decline of River Red Gum condition has been observed in many locations, and field observations of the degradation are consistent with the reduction of flooding. However, there are few publications that quantitatively investigate the relationships between River Red Gum condition and flooding history. We applied Classification and Regression Tree (CART) to model the minimum flooding requirement of River Red Gum forest/woodland in Yanga National Park, located on the Lower Murrumbidgee Floodplain, southeast Australia, using crown conditions derived from historical aerial photographs spanning more than 40 years. The model produced has a moderate reliability with an overall accuracy of 64·1% and a Kappa index of 0·543. The model brings in important insights about the relationship between River Red Gum community type, flood frequency and flood duration. Our results demonstrated that (1) CART analysis is a simple yet powerful technique with significant potential for application in river and environmental flow management; (2) River Red Gum communities on the Lower Murrumbidgee Floodplain require periodic inundation (3,5 years) for a duration of up to 64 days to be in moderate to good conditions; (3) Although the crown conditions of different community types displayed similar degradation trends, they have distinct flooding requirements; and (4) The River Red Gum community in Yanga National Park may be managed as hydrological units given limited environmental water allocations. Copyright © 2009 John Wiley & Sons, Ltd. [source] Evolutionary Economic Geography, Institutions, and Political EconomyECONOMIC GEOGRAPHY, Issue 2 2009Jürgen Essletzbichler abstract In this response to MacKinnon et al. (2009), I argue that the theoretical development of evolutionary economic geographies is necessary in order to evaluate its unique contribution to an understanding of the uneven development of the space economy; that the distinction between evolutionary and institutional economic geographies is overdrawn; that the neglect of class, power, and the state reflect empirical rather than theoretical shortcomings of the evolutionary approach; and that there is significant potential overlap between evolutionary and political economy approaches. [source] A microfabricated capillary electrophoresis chip with multiple buried optical fibers and microfocusing lens for multiwavelength detectionELECTROPHORESIS, Issue 6 2005Suz-Kai Hsiung Abstract We present a new microfluidic device utilizing multiwavelength detection for high-throughput capillary electrophoresis (CE). In general, different fluorescent dyes are only excited by light sources with appropriate wavelengths. When excited by an appropriate light source, a fluorescent dye emits specific fluorescence signals of a longer wavelength. This study designs and fabricates plastic micro-CE chips capable of performing multiple-wavelength fluorescence detection by means of multimode optic fiber pairs embedded downstream of the separation channel. For detection purposes, the fluorescence signals are enhanced by positioning microfocusing lens structures at the outlets of the excitation fibers and the inlets of the detection fibers, respectively. The proposed device is capable of detecting multiple samples labeled with different kinds of fluorescent dyes in the same channel in a single run. The experimental results demonstrate that various proteins, including bovine serum albumin and ,-casein, can be successfully injected and detected by coupling two light sources of different wavelengths to the two excitation optic fibers. Furthermore, the proposed device also provides the ability to measure the speed of the samples traveling in the microchannel. The developed multiwavelength micro-CE chip could have significant potential for the analysis of DNA and protein samples. [source] New alternative and complementary environmental policy instruments and the implementation of the Water Framework DirectiveENVIRONMENTAL POLICY AND GOVERNANCE, Issue 6 2008Andy Gouldson Abstract Based on a study conducted for the Environment Agency for England and Wales, we discuss the contribution that new alternative and complementary environmental policy instruments might make to the realization of the objectives of the EU's Water Framework Directive. Following a survey that identified nearly 100 examples where alternative and complementary instruments are currently being applied in the UK, we categorize such instruments as information-based approaches, private and voluntary regulation or support and capacity building measures. Examples are given of each category of instrument before further findings on the preconditions for the successful application of such measures are presented. These preconditions relate to levels of commitment from key groups, levels of stakeholder understanding, the role of the lead actor, the importance of timing, the need to deliver a clear message, the importance of enforcement, the role of the media and the importance of social capital in key networks. We conclude that alternative and complementary measures have significant potential to contribute to the realization of the Water Framework Directive's objectives, but only where these preconditions are met. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment. [source] Ni2+ removal from aqueous solutions using conditioned clinoptilolites: Kinetic and isotherm studiesENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 1 2009Semra Çoruh Abstract The aim of this study is to investigate the effects of conditioning with NaCl and HCl solutions on removal of Ni2+ ions from aqueous solutions using natural clinoptilolite. Batch studies were performed to evaluate the effects of various parameters such as chemically conditioning, adsorbent amount, contact time, initial pH of the solution, mixing temperature, and initial metal ions. The results clearly showed that the conditioning improved both the exchange capacity and the removal efficiency. Langmuir, Freundlich, Temkin, and Dubinin-Kaganer-Radushkevich (DKR) isotherm models were adopted to describe the adsorption isotherms. Adsorption isotherms of Ni2+ ions could be best modeled by Langmuir equation. Three simplified models including pseudo-second-order, intraparticle diffusion and Elovich were used to test the adsorption kinetics. These results indicate a significant potential for the natural and conditioned clinoptilolites as an adsorbent/ion-exchange material for heavy metal removal. © 2008 American Institute of Chemical Engineers Environ Prog, 2009 [source] Benefit-Cost Analysis of Addiction Treatment: Methodological Guidelines and Empirical Application Using the DATCAP and ASIHEALTH SERVICES RESEARCH, Issue 2 2002Michael T. French Objective. To provide detailed methodological guidelines for using the Drug Abuse Treatment Cost Analysis Program (DATCAP) and Addiction Severity Index (ASI) in a benefit-cost analysis of addiction treatment. Data Sources/Study Setting. A representative benefit-cost analysis of three outpatient programs was conducted to demonstrate the feasibility and value of the methodological guidelines. Study Design. Procedures are outlined for using resource use and cost data collected with the DATCAP. Techniques are described for converting outcome measures from the ASI to economic (dollar) benefits of treatment. Finally, principles are advanced for conducting a benefit-cost analysis and a sensitivity analysis of the estimates. Data Collection/Extraction Methods. The DATCAP was administered at three outpatient drug-free programs in Philadelphia, PA, for 2 consecutive fiscal years (1996 and 1997). The ASI was administered to a sample of 178 treatment clients at treatment entry and at 7-months postadmission. Principal Findings. The DATCAP and ASI appear to have significant potential for contributing to an economic evaluation of addiction treatment. The benefit-cost analysis and subsequent sensitivity analysis all showed that total economic benefit was greater than total economic cost at the three outpatient programs, but this representative application is meant to stimulate future economic research rather than justifying treatment per se. Conclusions. This study used previously validated, research-proven instruments and methods to perform a practical benefit-cost analysis of real-world treatment programs. The study demonstrates one way to combine economic and clinical data and offers a methodological foundation for future economic evaluations of addiction treatment. [source] Cover Picture: Biomineralized Polysaccharide Capsules for Encapsulation, Organization, and Delivery of Human Cell Types and Growth Factors (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 6 2005Mater. Abstract The cover shows biomineralized polysaccharide capsules with specifiable make-up, which can provide microenvironments for stabilization, growth, and differentiation of human cell types, as reported by Oreffo and co-workers on p.,917. The capsules are amenable to complexation with a range of bioactive molecules and cells, offering tremendous potential as multifunctional scaffolds and delivery vehicles in tissue regeneration of hard and soft tissues. The construction of biomimetic microenvironments with specific chemical and physical cues for the organization and modulation of a variety of cell populations is of key importance in tissue engineering. We show that a range of human cell types, including promyoblasts, chondrocytes, adipocytes, adenovirally transduced osteoprogenitors, immunoselected mesenchymal stem cells, and the osteogenic factor, rhBMP-2 (BMP: bone morphogenic protein), can be successfully encapsulated within mineralized polysaccharide capsules without loss of function in vivo. By controlling the extent of mineralization within the alginate/chitosan shell membrane, degradation of the shell wall and release of cells or rhBMP-2 into the surrounding medium can be regulated. In addition, we describe for the first time the ability to generate bead-in-bead capsules consisting of spatially separated cell populations and temporally separated biomolecule release, entrapped within alginate/chitosan shells of variable thickness, mineralization, and stability. Such materials offer significant potential as multifunctional scaffolds and delivery vehicles in tissue regeneration of hard and soft tissues. [source] Biomineralized Polysaccharide Capsules for Encapsulation, Organization, and Delivery of Human Cell Types and Growth Factors,ADVANCED FUNCTIONAL MATERIALS, Issue 6 2005W. Green Abstract The construction of biomimetic microenvironments with specific chemical and physical cues for the organization and modulation of a variety of cell populations is of key importance in tissue engineering. We show that a range of human cell types, including promyoblasts, chondrocytes, adipocytes, adenovirally transduced osteoprogenitors, immunoselected mesenchymal stem cells, and the osteogenic factor, rhBMP-2 (BMP: bone morphogenic protein), can be successfully encapsulated within mineralized polysaccharide capsules without loss of function in vivo. By controlling the extent of mineralization within the alginate/chitosan shell membrane, degradation of the shell wall and release of cells or rhBMP-2 into the surrounding medium can be regulated. In addition, we describe for the first time the ability to generate bead-in-bead capsules consisting of spatially separated cell populations and temporally separated biomolecule release, entrapped within alginate/chitosan shells of variable thickness, mineralization, and stability. Such materials offer significant potential as multifunctional scaffolds and delivery vehicles in tissue regeneration of hard and soft tissues. [source] Performance analysis of gas liquefaction cyclesINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 1 2008Mehmet Kanoglu Abstract Relations are developed for first- and second-law analyses of the simple Linde,Hampson cycle used in gas liquefaction systems. An expression for the minimum work requirement, which is applicable to any gas liquefaction system, is developed with the help of a Carnot refrigerator. It is shown that the minimum work depends only on the properties of the incoming and outgoing gas streams and the environment temperature. Numerical calculations are performed to obtain the performance parameters of different gases while parametric studies are done to investigate the effects of liquefaction and inlet gas temperatures on various first- and second-law performance parameters. As the liquefaction temperature increases and the inlet gas temperature decreases, the liquefied mass fraction, the coefficient of performance (COP) and the exergy efficiency increase while actual and reversible work consumptions decrease. The exergy efficiency values appear to be low, indicating significant potential exists for improving efficiency and thus decreasing the required work consumption for a specified amount of liquefaction. Copyright © 2007 John Wiley & Sons, Ltd. [source] Geothermal energy utilization in TurkeyINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 9 2001G. G. Gunerhan Abstract This paper investigates the status of geothermal development in Turkey as of the end of 1999. Turkey is one of the countries with significant potential in geothermal energy. Resource assessments have been made many times by the Mineral Research and Exploration Directorate (MTA) of Turkey. The main uses of geothermal energy are mostly moderate- and low-temperature applications such as space heating and domestic hot water supply, greenhouse heating, swimming and balneology, industrial processes, heat pumps and electricity generation. The data accumulated since 1962 show that the estimated geothermal power and direct use potential are about 4500 MWe and 31 500 MWt, respectively. The direct use capacity in thermal applications is in total 640 MWt representing only 2 per cent of its total potential. Since 1990, space heating and greenhouse developments have exhibited a significant progress. The total area of greenhouses heated by geothermal energy reached up to about 31 ha with a heating capacity of 69.61 MWt. A geothermal power plant with a capacity of 20.4 MWe and a CO2 factory with a capacity of 40000 ton yr,1 have been operated in the Denizli-Kizildere field since 1984 and 1986, respectively. Ground source heat pumps have been used in residential buildings for heating and cooling for approximately 2 years. Present applications have shown that geothermal energy in Turkey is clean and much cheaper compared to the other energy sources like fossil fuels and therefore is a promising alternative. As the projects are recognized by the public, the progress will continue. Copyright © 2001 John Wiley & Sons, Ltd. [source] Effectiveness of general practice nurse interventions in cardiac risk factor reduction among adultsINTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 3 2007Elizabeth Halcomb RN BN(Hons) Grad Cert. Abstract Background, Cardiovascular disease is the leading cause of death for adults in Australia. In recent years there has been a shift in health service delivery from institutional to community-based care for chronic conditions, including cardiovascular disease. The general practice setting is seen to offer greater flexibility, higher levels of efficiency and more client focused healthcare delivery than is possible in the acute care sector. It has been suggested that practice nurses represent a useful adjunct to current models of cardiovascular disease management. To date, significant descriptive research has been conducted exploring the demographics, roles, educational needs and issues facing practice nurses. However, there is a need to evaluate the effectiveness of practice nurse interventions in terms of patient outcomes, clinician satisfaction and cost-effectiveness. Objectives, This review seeks to present the best available evidence regarding the efficacy of general practice nurse interventions for cardiac risk factor reduction in healthy adults, as well as those with established cardiovascular disease or known cardiac risk factors. Search Strategy, A systematic literature search was performed using Medline (1966 , 2005), CINAHL (1982 ,2005), Cochrane Controlled Trials Register (Issue 4, 2005) and the Joanna Briggs Institute Evidence Library. In addition, the reference lists of retrieved papers, conference proceedings and the Internet, were scrutinised for additional trials. Selection Criteria, This review considered any English language randomised trials that investigated interventions conducted by the practice nurse for cardiovascular disease management or reduction of cardiac risk factors. Interventions conducted by specialist cardiac nurses in general practice were excluded. Outcomes measured included blood pressure, smoking cessation, total cholesterol, exercise, body weight/body mass index and cost-effectiveness. Results, Eighteen trials, reported in 33 papers, were included in the review. Ten trials investigated multifaceted interventions, while the remaining eight trials reported targeted interventions. Of the trials that reported multifaceted interventions, three trials investigated risk reduction in those with established cardiovascular disease, four trials focused on those with known cardiovascular disease risk factors and three trials included the general community. The eight trials which examined the efficacy of targeted interventions focused upon dietary intake (two trials), smoking cessation (three trials), weight reduction (one trial) and physical activity (two trials). The effect of both the multifaceted and targeted interventions on patient outcomes was variable. However, both the multifaceted and targeted interventions demonstrated similar outcome trends for specific variables. Improvements were demonstrated by most studies in blood pressure, cholesterol level, dietary intake and physical activity. The variation in outcome measures and contradictory findings between some studies makes it difficult to draw definitive conclusions. Conclusions, While interventions to reduce cardiovascular disease risk factors have produced variable results, they offer significant potential to assist patients in modifying their personal risk profile and should be developed. The public health importance of these changes is dependant upon the sustainability of the change and its effect on the health outcomes of these individuals. Further well-designed research is required to establish the effectiveness of practice nurse interventions for cardiovascular disease management and risk factor reduction in terms of patient outcomes and cost-effectiveness. [source] A Feasibility Study for the Investigation of Submerged Sites along the Coast of SloveniaINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 1 2009Jonathan Benjamin Maritime investigations along the Northern Adriatic coast have traditionally focused on the Roman and later archaeology. However, studies of post-glacial sea-level change and shoreline displacement suggest there is significant potential for the discovery of sites close inshore dating back to the early- to mid-Holocene, c.9000 BC onwards. A feasibility study for the investigation of submerged sites along the coast of Slovenia was undertaken in 2005. Here we describe the project rationale and research design, the survey and recording methods used, the logistical problems encountered, the results obtained (regardless of age), and the prospects for future research in the region. © 2009 The Authors [source] International Regimes: The Case of Western Corporate GovernanceINTERNATIONAL STUDIES REVIEW, Issue 2 2006DAVID A. DETOMASI Accounting and financial scandals of unprecedented scale have recently occurred in the United States, Europe, and elsewhere. Much of the cause for these scandals has been attributed to the poor corporate governance standards practiced by the offending companies, leading researchers to re-examine how corporate governance affects economic development. One topic receiving significant research attention has been whether national corporate governance systems are likely to converge, what form that convergence may take, and what barriers currently inhibit convergence. This essay argues that the tools of regime theory hold significant potential for helping to structure empirical inquiry into the process of corporate governance convergence. It then draws upon the recent experience of Western corporate governance systems to illustrate how a consensus on norms, values, and principles in the issue area of corporate governance is emerging. The essay concludes by drawing out the implications of the developing corporate governance regime for emerging market economies and the general topic of global governance. It also poses questions for continued empirical research in the area of corporate governance and international relations. [source] Chronic, painful lower extremity wounds: postoperative pain management through the use of continuous infusion of regional anaesthesia supplied by a portable pump deviceINTERNATIONAL WOUND JOURNAL, Issue 3 2010Christy L Scimeca Reducing and preventing postoperative pain are currently a topic of great interest. There are different modalities for providing analgesia that can provide an alternative or adjunct to opioid therapy. One mode of therapy involves the use of portable pain pump devices that can deliver continuous local anaesthesia directly to the site of interest. A considerable amount of attention in literature has been dedicated to using regional anaesthesia postoperatively for various surgical applications. However, to our knowledge, little or no work has been published concerning the use of infusion of regional anaesthesia in the treatment of painful lower extremity wounds. We present a case report of a 55-year-old gentleman with a complex past medical history, 2-year history of opioid dependency and a 2-week history of intractable pain associated with the combination of debilitating painful diabetic neuropathy and painful lower extremity wounds. After surgical debridement of the lower extremity wounds, substantial analgesia was achieved postoperatively through the implantation of a portable direct infusion pump device. The device supplied 2 ml/hour of 0·25% bupivacaine and resulted in a reduction in pain within the first hour of implantation. Although the device achieved maximal analgesia at 6 hours, we found that this could have been likely reduced through the use of a 5-ml bolus dose of 0·25% bupivacaine at the time of implantation. The device provided sufficient analgesia to the patient without any observed adverse effects, and showed significant potential in avoiding an increase in his requirement for other systemic analgesia including opioids. [source] Bacterial community structure, compartmentalization and activity in a microbial fuel cellJOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2006G.T. Kim Abstract Aims:, To characterize bacterial populations and their activities within a microbial fuel cell (MFC), using cultivation-independent and cultivation approaches. Methods and Results:, Electron microscopic observations showed that the fuel cell electrode had a microbial biofilm attached to its surface with loosely associated microbial clumps. Bacterial 16S rRNA gene libraries were constructed and analysed from each of four compartments within the fuel cell: the planktonic community; the membrane biofilm; bacterial clumps (BC) and the anode biofilm. Results showed that the bacterial community structure varied significantly between these compartments. It was observed that Gammaproteobacteria phylotypes were present at higher numbers within libraries from the BC and electrode biofilm compared with other parts of the fuel cell. Community structure of the MFC determined by analyses of bacterial 16S rRNA gene libraries and anaerobic cultivation showed excellent agreement with community profiles from denaturing gradient gel electrophoresis (DGGE) analysis. Conclusions:, Members of the family Enterobacteriaceae, such as Klebsiella sp. and Enterobacter sp. and other Gammaproteobacteria with Fe(III)-reducing and electrochemical activity had a significant potential for energy generation in this system. Significance and Impact of the Study:, This study has shown that electrochemically active bacteria can be enriched using an electrochemical fuel cell. [source] Preliminary investigations into a potential ant invader in Kruger National Park, South AfricaAFRICAN JOURNAL OF ECOLOGY, Issue 3 2010Hendrik Sithole Abstract The super-abundance of Lepisiota incisa (Forel) in settlement areas of Kruger National Park, South Africa has raised concerns that it might be exotic and could negatively impact on natural ecosystems. We documented the current distribution of this ant species around the main settlement in Kruger, assessed how ant diversity varies across habitats, and investigated potential mechanisms facilitating dominance by L. incisa. Around the main camp of Skukuza, pitfall traps were set in five habitats differing in anthropogenic influence. Baiting trails were conducted to determine whether L. incisa and native ants differed in numerical and behavioural dominance. Aggression assays were performed on L. incisa to provide information on colony structure. Although L. incisa was found in all habitats, it had a significantly higher abundance in gardens and appears confined to human-disturbed areas. It was numerically dominant recruiting more workers to food baits than all other ant species combined. Aggression levels were low between most nests of L. incisa indicating a potential supercolony structure. More information is urgently needed on the genetics, physiology and origins of L. incisa, and monitoring of its current distribution is recommended. This species warrants attention because there may be significant potential for overseas invasion. Résumé La surabondance de Lepisiota incisa (Forel) dans des zones d'installations du Parc National Kruger, en Afrique du Sud, a suscité des inquiétudes quant au fait que cette espèce pourrait être exotique et avoir un impact négatif sur des écosystèmes naturels. Nous avons documenté la distribution actuelle de cette espèce de fourmi autour de la principale installation dans le Kruger, évalué comment la diversité des fourmis varie selon les habitats et étudié les mécanismes éventuels qui pourraient faciliter la dominance de L. incisa. On a installé des pièges autour du camp principal de Skukuza, dans cinq habitats où l'influence anthropogénique diffère. On a réalisé des pistes appâts pour déterminer si L. incisa et les fourmis indigènes différaient en matière de dominance numérique et comportementale. Nous avons fait des essais d'agression sur L. incisa pour donner des informations sur la structure de la colonie. Bien que l'on ait trouvéL. incisa dans tous les habitats, elle était beaucoup plus abondante dans les jardins et elle semble se confiner aux endroits perturbés par les hommes. Elle était numériquement dominante, recrutant plus d'ouvrières pour les appâts que toutes les autres espèces mises ensemble. Le niveau d'agression entre la plupart des nids de L. incisaétait bas, ce qui indique peut-être une structure de super-colonie. Il faut obtenir d'urgence d'autres informations sur la génétique, la physiologie et les origines de L. incisa et l'on recommande de faire le suivi de sa distribution actuelle. Cette espèce mérite l'attention parce qu'elle peut certainement être une espèce invasive outre-mer. [source] Alveolar ridge augmentation using implants coated with recombinant human bone morphogenetic protein-7 (rhBMP-7/rhOP-1): radiographic observationsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 10 2008Knut N. Leknes Abstract Aim: The objective of this study was to radiographically evaluate the potential of a purpose-designed titanium porous-oxide implant surface coated with recombinant human bone morphogenetic protein-7 (rhBMP-7), also known as recombinant human osteogenic protein-1 (rhOP-1), to stimulate alveolar ridge augmentation. Material and Methods: Six young-adult Hound Labrador mongrel dogs were used. Three 10 mm titanium oral implants per jaw quadrant were placed 5 mm into the alveolar ridge in the posterior mandible following surgical extraction of the pre-molar teeth and reduction of the alveolar ridge leaving 5 mm of the implants in a supra-alveolar position. The implants had been coated with rhBMP-7 at 1.5 or 3.0 mg/ml and were randomized to contralateral jaw quadrants using a split-mouth design. The mucoperiosteal flaps were advanced, adapted, and sutured to submerge the implants. Radiographic registrations were made immediately post-surgery (baseline), and at weeks 4 and 8 (end of study). Results: rhBMP-7-coated implants exhibited robust radiographic bone formation. At 8 weeks, bone formation averaged 4.4 and 4.2 mm for implants coated with rhBMP-7 at 1.5 and 3.0 mg/ml, respectively. There were no significant differences between the rhBMP-7 concentrations at any observation interval. A majority of the implant sites showed voids within the newly formed bone at week 4 that generally resolved by week 8. The newly formed bone assumed characteristics of the resident bone. Conclusions: The titanium porous-oxide implant surface serves as an effective carrier for rhBMP-7 showing a clinically significant potential to stimulate local bone formation. [source] The appropriation and repurposing of social technologies in higher educationJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 1 2009A. Hemmi Abstract This paper presents some of the findings from a recent project that conducted a virtual ethnographic study of three formal courses in higher education that use ,Web 2.0' or social technologies for learning and teaching. It describes the pedagogies adopted within these courses, and goes on to explore some key themes emerging from the research and relating to the pedagogical use of weblogs and wikis in particular. These themes relate primarily to the academy's tendency to constrain and contain the possibly more radical effects of these new spaces. Despite this, the findings present a range of student and tutor perspectives which show that these technologies have significant potential as new collaborative, volatile and challenging environments for formal learning. [source] Reconstructing asymmetrical reproductive character displacement in a periodical cicada contact zoneJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2006JOHN R. COOLEY Abstract Selection against costly reproductive interactions can lead to reproductive character displacement (RCD). We use information from patterns of displacement and inferences about predisplacement character states to investigate causes of RCD in periodical cicadas. The 13-year periodical cicada Magicicada neotredecim exhibits RCD and strong reproductive isolation in sympatry with a closely related 13-year species, Magicicada tredecim. Displacement is asymmetrical, because no corresponding pattern of character displacement exists within M. tredecim. Results from playback and hybridization experiments strongly suggest that sexual interactions between members of these species were possible at initial contact. Given these patterns, we evaluate potential sources of selection for displacement. One possible source is ,acoustical interference', or mate-location inefficiencies caused by the presence of heterospecifics. Acoustical interference combined with the species-specificity of song pitch and preference appears to predict the observed asymmetrical pattern of RCD in Magicicada. However, acoustical interference does not appear to be a complete explanation for displacement in Magicicada, because our experiments suggest a significant potential for direct sexual interactions between these species before displacement. Another possible source of selection for displacement is hybrid failure. We evaluate the attractiveness of inferred hybrid mating signals, and we examine the viability of hybrid eggs. Neither of these shows strong evidence of hybrid inferiority. We conclude by presenting a model of hybrid failure related to life cycle differences in Magicicada. [source] The effects of insect pathogenic soil fungi and ectomycorrhizal inoculation of birch seedlings on the survival of Otiorhynchus larvaeAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2010Edda S. Oddsdottir 1Weevil larvae of the genus Otiorhynchus are a serious problem in agriculture and forestry, causing damage to a wide range of plant species, primarily by larval feeding on roots. Otiorhynchus larvae are a serious pest in forest plantations in Iceland, causing 10,20% mortality of newly-planted seedlings. 2We studied the effects of soil fungi on the survival of Otiorhynchus sulcatus larvae. The larvae were introduced into pots with birch seedlings grown in: (i) nursery peat; (ii) nursery peat inoculated with three different species of ectomycorrhizal fungi; (iii) nursery peat inoculated with insect pathogenic fungi; (iv) nursery peat inoculated with ectomycorrhizal fungi and insect pathogenic fungi; and (v) nursery peat inoculated with natural forest soil from Icelandic birch woodland. 3Larval survival was negatively affected by inoculation of: (i) the ectomycorrhizal fungus Laccaria laccata; (ii) the ectomycorrhizal fungus Cenococcum geophylum; (iii) the insect pathogenic fungus Metarhizium anisopliae; and (iv) forest soil. Inoculation with the ectomycorrhizal fungus Phialophora finlandia did not have any significant effect on larval survival. No significant synergistic effect was found between insect pathogenic and ectomycorrhizal fungi. 4It is concluded that ectomycorrhizal and insect pathogenic fungi have a significant potential in biological control of Otiorhynchus larvae in afforestation areas in Iceland. Further studies are needed to establish the effect of these fungi in the field and to analyse how mycorrhizal fungi affect root-feeding larvae. [source] Building Material Flow Accounts in the United StatesJOURNAL OF INDUSTRIAL ECOLOGY, Issue 5-6 2008A Case Study in Public Sector Innovation Summary Building a national system of material flow accounts in the United States could be an important step toward natural resource sustainability. But the task will not be as simple as "If you build it, they will come." The key to understanding the status of and prospects for official material flow accounts in the United States is to see the picture from the point of view of public sector and environmental innovation generally, rather than from the point of view of building the details of the accounts themselves. A simple model of public sector innovation helps explain what is happening and what needs to happen to make further progress. The model used here has four principal elements: methods, organizational capacity, demand, and actual use. The details and sequence of these elements vary in different situations, but all four must be present for successful innovations. Although aspects of culture, innovation, and government bureaucracy differ from country to country, the basic model appears to be similar across borders, at least in countries belonging to the Organisation for Economic Cooperation and Development (OECD). Seen this way, recent events in the United States indicate that (1) there is significant potential for such accounts; (2) the United States is moving toward creating them, although not in a systematic manner, which means that the progression and eventual outcome are uncertain; and (3) there are ways for the research community to participate very positively in the public process. [source] Role of neuroimaging in promoting long-term recovery from ischemic strokeJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2010Rüdiger J. Seitz MD Abstract Human ischemic stroke is an acute disorder followed by a recovery period which may be of varying duration and mechanism. Imaging has created a means to explore the stroke process in vivo, particularly its underlying pathophysiology and recovery mechanisms. Evidence from multicenter studies has shown that, in the acute phase, arterial recanalization and reperfusion of ischemic brain tissue are the most important determinants of recovery. This is followed by functional and structural changes in the perilesional tissue and in large-scale bihemispheric networks that continue with different dynamics for weeks to months. Proof-of-principle studies have revealed that the behavioral gains induced by rehabilitation are paralleled by changes in functional representations. This is supported by data from neuroimaging and electrophysiological studies early after stroke which have shown that dedicated training can induce changes in cerebral functional representations. Accordingly, there is clear evidence that neuroimaging has a significant potential for monitoring the hemodynamic, functional, and structural factors determining recovery from stroke. New imaging methods may provide relevant biomarkers for treatment decisions and therapeutic monitoring. By combining neuroimaging with electrophysiological measures, opportunities exist to develop neuroscience-based strategies in rehabilitation. J. Magn. Reson. Imaging 2010;32:756,772. © 2010 Wiley-Liss, Inc. [source] Cytotoxic effects of gingival retraction cords on human gingival fibroblasts in vitroJOURNAL OF ORAL REHABILITATION, Issue 4 2004C.-M. Liu summary, The objective of this study was to determine the cytocompatibility of three different extracts of gingival retraction cords and to compare the cytotoxic effect of these materials on human gingival fibroblasts. Gingival retraction cords impregnated with aluminium sulphate (Gingi-Aid), dl -adrenaline HCl (Gingi-Pak) and non-drug-impregnated cord (Gingi-Plain) were eluted with culture medium for 10 min and 24 h. Cytotoxicity was judged using a tetrazolium bromide reduction assay. Our data demonstrated that gingival retraction cords applied alone almost completely inhibited cell viability (P < 0·05). In addition, the results also showed that the eluates from aluminium sulphate-impregnated cord, dl -adrenaline HCl-impregnated cord and non-drug-impregnated cord were cytotoxic to primary human gingival fibroblast cultures (P < 0·05). The cell viability of incubation of gingival fibroblasts containing 10-min eluates of aluminium sulphate, dl -adrenaline HCl and non-drug-impregnated cord was 61, 21 and 70%, respectively. The cell viability of incubation of gingival fibroblasts containing 24 h eluates of aluminium sulphate, dl -adrenaline HCl and non-drug-impregnated cord was 68, 58 and 72%, respectively. It was found that dl -adrenaline HCl-impregnated gingival retraction cord was the most toxic gingival retraction cord among the materials tested in all cultures (P < 0·05). The cytotoxicity decreased in an order of dl -adrenaline HCl-impregnated cord > aluminium sulphate-impregnated cord > non-drug-impregnated cord. The extent or degree of the cytotoxicity depended on the materials tested. Gingival retraction cords have significant potential for gingival toxicity. Careful management of gingiva retraction cords would lower the risk of potential gingival tissue damage during clinical application procedure and thus increase the success of prosthodontic procedures. [source] Fabrication, characterization and in vitro evaluation of poly(D,L -lactide- co -glycolide) microparticles loaded with polyamidoamine,plasmid DNA dendriplexes for applications in nonviral gene deliveryJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 1 2010Janjira Intra Abstract We report, for the first time, on the preparation, characterization and in vitro testing of poly(D,L -lactide- co -glycolide) (PLGA) microparticles loaded with polyamidoamine (PAMAM),plasmid DNA (pDNA) dendriplexes. Loading of pDNA into the PLGA microparticles increased by 150% when pDNA was first complexed with PAMAM dendrimers relative to loading of pDNA alone. Scanning electron microscopy (SEM) showed that the presence of PAMAM dendrimers in the PLGA microparticles created porous features and indentations on the surface of the microparticles. Loading PLGA microparticles with PAMAM,pDNA dendriplexes lowered the average PLGA microparticle size and changed the surface charge of the microparticles from negative to positive when compared to PLGA microparticles loaded with pDNA alone. The zetapotential and buffering capacity of the microparticles increased as the generation of the PAMAM dendrimer loaded in the PLGA microparticles increased. Gel electrophoresis assays showed that all the PLGA microparticle formulations were able to entrap the pDNA within the PLGA matrix. There was no significant difference in the cytotoxicity of PLGA microparticles loaded with PAMAM,pDNA dendriplexes when compared to PLGA microparticles loaded with pDNA alone. Furthermore, and in contrast to PAMAM dendrimers alone, the generation of the PAMAM dendrimer loaded in the PLGA microparticles had no significant impact on cytotoxicity or transfection efficiencies in human embryonic kidney (HEK293) or Monkey African green kidney fibroblast-like (COS7) cells. The transfection efficiency of PLGA microparticles loaded with generation 3 (G3) PAMAM,pDNA dendriplexes was significantly higher than PLGA microparticles loaded with pDNA alone in HEK293 and COS7 cells. PLGA microparticles loaded with G3 PAMAM,pDNA dendriplexes generated equivalent transfection efficiencies as (G3 to G6) PAMAM,pDNA dendriplexes alone in COS7 cells when the transfection was carried out in serum containing media. The delivery system developed in this report has low toxicity, high pDNA loading efficiencies and high transfection efficiencies that are not reduced in the presence of serum. A delivery system with these characteristics is expected to have significant potential for translational applications. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:368,384, 2010 [source] Novel bromomelatonin derivatives suppress osteoclastic activity and increase osteoblastic activity: implications for the treatment of bone diseasesJOURNAL OF PINEAL RESEARCH, Issue 3 2008Nobuo Suzuki Abstract:, The teleost scale is a calcified tissue that contains osteoclasts, osteoblasts, and bone matrix, all of which are similar to those found in mammalian membrane bone. Using the goldfish scale, we recently developed a new in vitro assay system and previously demonstrated that melatonin suppressed both osteoclastic and osteoblastic activities in this assay system. In mammals, 2-bromomelatonin possesses a higher affinity for the melatonin receptor than does melatonin. Using a newly developed synthetic method, we synthesized 2-bromomelatonin, 2,4,6-tribromomelatonin and novel bromomelatonin derivatives (1-allyl-2,4,6-tribromomelatonin, 1-propargyl-2,4,6-tribromomelatonin, 1-benzyl-2,4,6-tribromomelatonin, and 2,4,6,7-tetrabromomelatonin) and then examined the effects of these chemicals on osteoclasts and osteoblasts. All bromomelatonin derivatives, as well as melatonin, had an inhibitory action on osteoclasts. In particular, 1-benzyl-2,4,6-tribromomelatonin (benzyl-tribromomelatonin) possessed a stronger activity than melatonin. At an in vitro concentration of 10,10 m, benzyl-tribromomelatonin still suppressed osteoclastic activity after 6 hr of incubation. In reference to osteoblasts, all bromomelatonin derivatives had a stimulatory action, although melatonin inhibited osteoblastic activity. In addition, estrogen receptor mRNA expression (an osteoblastic marker) was increased in benzyl-tribromomelatonin (10,7 m)-treated scales. Taken together, the present results strongly suggest that these novel melatonin derivatives have significant potential for use as beneficial drug for bone diseases such as osteoporosis. [source] Synthesis of metal/polymer colloidal composites by the tailored deposition of silver onto porous polymer microspheresJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2004Jin-Woong Kim Abstract A new colloidal silver system is presented in which a fine colloidal silver is in situ deposited onto functionalized porous poly(ethylene glycol dimethacrylate) [poly(EGDMA)] microspheres. The effectiveness of the silver deposition has been investigated through an examination of the surface characteristics of poly(EGDMA) microspheres. The result reported in this study demonstrate that the control of the surface area and surface functionality (in this study, a hydroxyl group) of poly(EGDMA) microspheres is an important factor that practically determines the degree of deposition of colloidal silver. X-ray analysis has shown that silver nanoparticles are dispersed evenly on inner and outer surfaces and have a face center cubic phase. Preservation testing has shown that silver-containing poly(EGDMA) microspheres have powerful antibacterial properties and, therefore, have significant potential as new preservatives. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2551,2557, 2004 [source] | ||||||||||||||||||||||||||||