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High Potential (high + potential)
Selected AbstractsHigh potential of thin (<1,µm) a-Si: H/µc-Si:H tandem solar cellsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 2 2010S. Schicho Abstract Silicon based thin tandem solar cells were fabricated by plasma enhanced chemical vapor deposition (PECVD) in a 30,×,30,cm2 reactor. The layer thicknesses of the amorphous top cells and the microcrystalline bottom cells were significantly reduced compared to standard tandem cells that are optimized for high efficiency (typically with a total absorber layer thickness from 1.5 to 3,µm). The individual absorber layer thicknesses of the top and bottom cells were chosen so that the generated current densities are similar to each other. With such thin cells, having a total absorber layer thickness varying from 0.5 to 1.5,µm, initial efficiencies of 8.6,10.7% were achieved. The effects of thickness variations of both absorber layers on the device properties have been separately investigated. With the help of quantum efficiency (QE) measurements, we could demonstrate that by reducing the bottom cell thickness the top cell current density increased which is addressed to back-reflected light. Due to a very thin a-Si:H top cell, the thin tandem cells show a much lower degradation rate under continuous illumination at open circuit conditions compared to standard tandem and a-Si:H single junction cells. We demonstrate that thin tandem cells of around 550,nm show better stabilized efficiencies than a-Si:H and µc-Si:H single junction cells of comparable thickness. The results show the high potential of thin a-Si/µc-Si tandem cells for cost-effective photovoltaics. Copyright © 2010 John Wiley & Sons, Ltd. [source] Measurement of barbed ends, actin polymerization, and motility in live carcinoma cells after growth factor stimulation,CYTOSKELETON, Issue 4 2004Mike Lorenz Abstract Motility is associated with the ability to extend F-actin-rich protrusions and depends on free barbed ends as new actin polymerization sites. To understand the function and regulation of different proteins involved in the process of generating barbed ends, e.g., cofilin and Arp2/3, fixed cell approaches have been used to determine the relative barbed end concentration in cells. The major disadvantages of these approaches are permeabilization and fixation of cells. In this work, we describe a new live-cell time-lapse microscopy assay to determine the increase of barbed ends after cell stimulation that does not use permeabilization and provides a better time resolution. We established a metastatic carcinoma cell line (MTLn3) stably expressing GFP-,-actin at physiological levels. Stimulation of MTLn3 cells with epidermal growth factor (EGF) causes rapid and transient lamellipod protrusion along with an increase in actin polymerization at the leading edge, which can be followed in live cell experiments. By measuring the increase of F-actin at the leading edge vs. time, we were able to determine the relative increase of barbed ends after stimulation with a high temporal resolution. The F-actin as well as the barbed end concentration agrees well with published data for this cell line. Using this newly developed assay, a decrease in lamellipod extension and a large reduction of barbed ends was documented after microinjecting an anti-cofilin function blocking antibody. This assay has a high potential for applications where rapid changes in the dynamic filament population are to be measured. Cell Motil. Cytoskeleton 57:207,217, 2004. © 2004 Wiley-Liss, Inc. [source] Imaging studies of biodistribution and kinetics in drug developmentDRUG DEVELOPMENT RESEARCH, Issue 2 2003Marc S. Berridge Abstract Although the intravenous route of administration is rarely used for drugs, it is by far the most common route for PET and SPECT radiotracers. This article discusses the use of planar and tomographic nuclear medicine technologies to image and quantify the distribution of drugs after local administration. In principle, this would include topical dermatologic, otic, ophthalmic, rectal, and vaginal administration, as well as the intramuscular, oral, and inhalation routes, although precedents do not yet exist for all of these. The studies reviewed focus mainly on oral ingestion and oral and nasal inhalation. The use of nondrug tracers for formulations is discussed, principally with planar imaging or SPECT using radionuclides such as 99mTc, as well as PET imaging where the active ingredient of a formulation can be labeled with 11C or sometimes 18F. An example of the latter type is a study of the deposition and kinetics in the lungs and airways of triamcinolone acetonide, an antiinflammatory steroid used for topical treatment of allergic rhinitis and asthma, dispensed from an inhaler. PET has high potential for evaluation of different formulations and delivery devices in the development of topically applied drugs. Drug Dev. Res. 59:208,226, 2003. © 2003 Wiley-Liss, Inc. [source] Dendrogeomorphic reconstruction of past debris-flow activity using injured broad-leaved treesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2010Estelle Arbellay Abstract Tree-ring records from conifers have been regularly used over the last few decades to date debris-flow events. The reconstruction of past debris-flow activity was, in contrast, only very rarely based on growth anomalies in broad-leaved trees. Consequently, this study aimed at dating the occurrence of former debris flows from growth series of broad-leaved trees and at determining their suitability for dendrogeomorphic research. Results were obtained from gray alder (Alnus incana (L.) Moench), silver birch and pubescent birch (Betula pendula Roth and Betula pubescens Ehrh.), aspen (Populus tremula L.), white poplar, black poplar and gray poplar (Populus alba L., Populus nigra L. and Populus x canescens (Ait.) Sm.), goat willow (Salix caprea L.) and black elder (Sambucus nigra L.) injured by debris-flow activity at Illgraben (Valais, Swiss Alps). Tree-ring analysis of 104 increment cores, 118 wedges and 93 cross-sections from 154 injured broad-leaved trees allowed the reconstruction of 14 debris-flow events between AD 1965 and 2007. These events were compared with archival records on debris-flow activity at Illgraben. It appears that debris flows are very common at Illgraben, but only very rarely left the channel over the period AD 1965,2007. Furthermore, analysis of the spatial distribution of disturbed trees contributed to the identification of six patterns of debris-flow routing and led to the determination of preferential breakout locations of events. The results of this study demonstrate the high potential of broad-leaved trees for dendrogeomorphic research and for the assessment of the travel distance and lateral spread of debris-flow surges. Copyright © 2010 John Wiley & Sons, Ltd. [source] New Methylene Blue (NMB) Encapsulated in Mesoporous AlMCM-41 Material and Its Application for Amperometric Determination of Ascorbic Acid in Real SamplesELECTROANALYSIS, Issue 15 2007Shabnam Sohrabnezhad Abstract New methylene blue (NMB) dye incorporated into AlMCM-41 surfactant-free and hybrid surfactant-AlMCM-41 mesophase. UV-vis evidence shows that new methylene blue dye protonated in both cases of zeolites. New methylene blue is electroactive in zeolites and their electrochemical activity has been studied by cyclic voltammetry and compared to that of NMB in aqueous solutions. New methylene blue molecules are not released to the solution during CV measurements and are accessible to H3O+ ions. The presence of surfactant affects the kinetics of the redox process through proton ions diffusion. The midpoint potentials (Em) values show that new methylene blue dye incorporated into AlMCM-41 can be reduced easily with respect to solution new methylene blue. New methylene blue interacting with surfactant polar heads and residual Br, ions as a results, it shows a couple of peaks in high potential with respect to new methylene blue solution. The electrode made with methylene blue-AlMCM-41 without surfactant was used for the mediated oxidation of ascorbic acid. The anodic peak current observed in cyclic voltammetry was linearly dependent on the ascorbic acid concentration. The calibration plot was linear over the ascorbic acid concentration range 1.0×10,5 to 5.0×10,4 M. The detection limit of the method is 1.0×10,5 M, low enough for trace ascorbic acid determination in various real samples. [source] Molecular Neuropathology of Temporal Lobe Epilepsy: Complementary Approaches in Animal Models and Human Disease TissueEPILEPSIA, Issue 2007Michael Majores Summary:, Patients with temporal lobe epilepsies (TLE) frequently develop pharmacoresistance to antiepileptic treatment. In individuals with drug-refractory TLE, neurosurgical removal of the epileptogenic focus provides a therapy option with high potential for seizure control. Biopsy specimens from TLE patients constitute unique tissue resources to gain insights in neuropathological and molecular alterations involved in human TLE. Compared to human tissue specimens in most neurological diseases, where only autopsy material is available, the bioptic tissue samples from pharmacoresistant TLE patients open rather exceptional preconditions for molecular biological, electrophysiological as well as biochemical experimental approaches in human brain tissue, which cannot be carried out in postmortem material. Pathological changes in human TLE tissue are multiple and relate to structural and cellular reorganization of the hippocampal formation, selective neurodegeneration, and acquired changes of expression and distribution of neurotransmitter receptors and ion channels, underlying modified neuronal excitability. Nevertheless, human TLE tissue specimens have some limitations. For obvious reasons, human TLE tissue samples are only available from advanced, drug-resistant stages of the disease. However, in many patients, a transient episode of status epilepticus (SE) or febrile seizures in childhood can induce multiple structural and functional alterations that after a latency period result in a chronic epileptic condition. This latency period, also referred to as epileptogenesis, cannot be studied in human TLE specimens. TLE animal models may be particularly helpful in order to shed characterize new molecular pathomechanisms related to epileptogenesis and open novel therapeutic strategies for TLE. Here, we will discuss experimental approaches to unravel molecular,neuropathological aspects of TLE and highlight characteristics and potential of molecular studies in human and/or experimental TLE. [source] Tailoring Materials Properties by Accumulative Roll Bonding,ADVANCED ENGINEERING MATERIALS, Issue 8 2010Tina Hausöl Accumulative roll bonding (ARB) as a method of severe plastic deformation (SPD) is an interesting established process to produce ultrafine-grained (UFG) sheet materials with high potential for light weight constructions. The ARB process offers a high flexibility for tailored material design. Al2O3 particles, carbon fibers and titanium foils are used as reinforcement of aluminum sheets introduced during accumulative roll bonding. Furthermore multicomponent materials are produced by cladding of different aluminum alloys. These sandwich-like structures allow to combine desired properties of the materials involved. Post-ARB heat treatment offers another possibility for tailoring materials properties of graded structures as shown by formation of TiAl3 in Al/Ti laminates. The tailored materials are investigated by means of SEM, EDX, nanoindentation experiments and tensile testing. [source] Nanoscale Grain Refinement and H-Sorption Properties of MgH2 Processed by High-Pressure Torsion and Other Mechanical Routes,ADVANCED ENGINEERING MATERIALS, Issue 8 2010Daniel Rodrigo Leiva MgH2 is a promising material for solid-state hydrogen storage due to its high gravimetric and volumetric storage capacity and its relatively low cost. Severe plastic deformation (SPD) processing techniques are being explored as an alternative to high-energy ball-milling (HEBM) in order to obtain more air resistant materials and reduce processing times. In this work, Mg, MgH2, and MgH2,Fe mixtures were severely mechanically processed by different techniques such as high-pressure torsion (HPT), extensive cold forging, and cold rolling. A very significant grain refinement was achieved when using MgH2 instead of Mg as raw material. The mean crystallite sizes observed ranged from 10 to 30,nm, depending on the processing conditions. Enhanced H-sorption properties were observed for the MgH2 -based nanocomposites processed by HPT when compared with MgH2 mixtures. Additionally, cold forging and cold rolling also proved effective in nanostructuring MgH2. These results suggest a high potential for innovative application with the use of low cost mechanical processing routes to produce Mg-based nanomaterials with attractive hydrogen storage properties. [source] Metamaterials: How Far Are We from Making Metamaterials by Self-Organization?ADVANCED FUNCTIONAL MATERIALS, Issue 7 2010The Microstructure of Highly Anisotropic Particles with an SRR-Like Geometry (Adv. Funct. As part of ongoing efforts to create metamaterials by engineered self-organization using solidification of eutectics, D. A. Pawlak et al. report on page 1116 the fabrication of a fractal material with split-tubes mimicking (in cross section) the famous split-ring resonators (SRRs). The latter, when made of metal, are the basic element of a structure showing negative refractive index. This article shows that metallo-dielectric structures can be fabricated. The method employed has high potential for manufacturing materials with various functionalities. [source] Catalytic epoxide oxidation: a novel access to ,avouring and odorant , -diketonesFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2004Sylvain Antoniotti Abstract The catalytic oxidation of epoxides to , -diketones provides a novel access to a variety of ,avouring compounds and odorants. This alternative synthetic strategy involves an oxidation reaction catalysed by commercially available reagents and affords four cyclic and acyclic , -diketones presenting interesting organoleptic properties. The availability of epoxides, easily obtained by ole,n epoxidation, and the possibility of obtaining , -diketones with a variety of structures gives a high potential to this method. Copyright © 2004 John Wiley & Sons, Ltd. [source] Stable ,Floating' Air Diffusion Biocathode Based on Direct Electron Transfer Reactions Between Carbon Particles and High Redox Potential LaccaseFUEL CELLS, Issue 4 2010S. Shleev Abstract We report on the assembly and characterisation of a high potential, stable, mediator-less and cofactor free biocathode based on a fungal laccase (Lc), adsorbed on highly dispersed carbonaceous materials. First, the stability and activity of Trametes hirsuta Lc immobilised on different carbon particles were studied and compared to the solubilised enzyme. Based on the experimental results and a literature analysis, the carbonaceous material BM-4 was chosen to design efficient and stable biocatalysts for the production of a ,floating' air diffusion Lc-based biocathode. Voltammetric characteristics and operational stability of the biocathode were investigated. The current density of oxygen reduction at the motionless biocathode in a quiet, air saturated citrate buffer (100,mM, pH 4.5, 23,°C) reached values as high as 0.3,mA,cm,2 already at 0.7,V versus NHE. The operational stability of the biocathode depended on the current density of the device. For example, at low current density (20,,A,cm,2), the biocathode lost only 5× of its initial power after 1 month of continuous operation. However, when the device was polarised at 150,mV it lost more than 32× of its initial power in just 10,min. We also found that co-immobilisation of Lc and peroxidase on highly dispersed carbon materials could protect the biocatalyst from rapid inactivation by hydrogen peroxide produced during electrocatalytic reactions at high-current densities. [source] High-Pressure Synthesis of Tantalum Nitride Having Orthorhombic U2S3 StructureADVANCED FUNCTIONAL MATERIALS, Issue 14 2009Andreas Zerr Abstract Among binary compounds, there is a high potential for discovery of novel members (polymorphic phases or compounds) of the nitrides of transition metals group due to a pronounced dependence of the oxidation state of the metals (M) on pressure. The power of high pressure,high temperature (HP-HT) route for synthesis of binary nitrides has already been demonstrated by the discovery of cubic nitrides of the group 4 and 14 elements, of crystalline polymorphs of P3N5, and by reports on formation of four noble metal nitrides. It is anticipated that such HP products exhibit, in addition to enhanced elastic and mechanical behavior, other functional properties making them interesting for industrial applications. Here, HP,HT synthesis research is extended to nitrides of group 5 elements, resulting in the discovery of a novel hard tantalum nitride, exhibiting U2S3 structure: , -Ta2N3 (Pbnm, a,=,8.1911(17),Å, b,=,8.1830(17),Å, c,=,2.9823(3),Å). The stoichiometry is supported by two independent means, verifying that , -Ta2N3 is the first thermodynamically stable transition metal nitride with a N:M ratio exceeding 4:3. Due to its high hardness and peculiar texture (needle-like and granular crystallites), , -Ta2N3 may find practical applications as a hard fracture resistant material. [source] Early Holocene Paleoindian deposits at Nall Playa, Oklahoma Panhandle, U.S.A.GEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 1 2003Jason M. LaBelle Fieldwork conducted at the Nall North locale and the adjacent playa documents buried Paleoindian deposits and a stratigraphic sequence dating back to the late Pleistocene. Cultural debris recovered from the surface of Nall North includes bone, tools, and lithic flake debris. Two buried paleosols at the locale date to the early Holocene and hold high potential for Paleoindian materials. The Baker paleosol, a stabilized surface above the shoreline of the adjacent playa lake, dated between ca. 6870 and 7740 yr B.P., contains a rich cultural component of tools, flakes, and bone, and represents a potential surface for Angostura and Allen/Frederick artifacts. Located below the Baker soil is the Nall soil (dated to ca. 9650 yr B.P.) that probably represents a marsh facies of the playa fill. The Nall soil represents a potential surface for Plainview/Goshen-age artifacts, although excavations thus far have recovered no cultural debris. In the playa adjacent to the Nall North locality, a sequence dating between ca. 12,960 and 5310 yr B.P. documents localized spring flow into the playa during the late Pleistocene, followed by several thousand years of playa muds during the early Holocene, and the eventual drying of the playa in the middle Holocene. © 2003 Wiley Periodicals, Inc. [source] Early Carboniferous (Mississippian) calciturbidites in the northern Rhenish Mountains (Germany)GEOLOGICAL JOURNAL, Issue 2-3 2008D. Korn Abstract Viséan calciturbidites occur in two separate turbidite sequences at the northern margin of the Rhenish Mountains: (1) the Herdringen Sequence (Becke-Oese, Retringen and Herdringen formations), and (2) the Hellefeld Sequence (Hellefeld, Linnepe and Wennemen formations). Both sequences show temporal fluctuations in the carbonate content, which can be related to global eustatic fluctuations. Two peaks of carbonate sedimentation which occurred during lowstands in the Holkerian to early Asbian and in the Brigantian are interrupted by a late Asbian decline of carbonate deposition during a transgressive interval. Patterns of bed thickness and carbonate content in the Herdringen Sequence indicate a sediment source to the north; it shifted during the Late Viséan from the northeast to the northwest. Coeval sediments in the Hellefeld Sequence were derived from a source to the southeast. Detailed analyses of Asbian sections show the high potential for fine-scaled correlation. Copyright © 2007 John Wiley & Sons, Ltd. [source] Shrub expansion stimulates soil C and N storage along a coastal soil chronosequenceGLOBAL CHANGE BIOLOGY, Issue 7 2010STEVEN T. BRANTLEY Abstract Expansion of woody vegetation in grasslands is a worldwide phenomenon with implications for C and N cycling at local, regional and global scales. Although woody encroachment is often accompanied by increased annual net primary production (ANPP) and increased inputs of litter, mesic ecosystems may become sources for C after woody encroachment because stimulation of soil CO2 efflux releases stored soil carbon. Our objective was to determine if young, sandy soils on a barrier island became a sink for C after encroachment of the nitrogen-fixing shrub Morella cerifera, or if associated stimulation of soil CO2 efflux mitigated increased litterfall. We monitored variations in litterfall in shrub thickets across a chronosequence of shrub expansion and compared those data to previous measurements of ANPP in adjacent grasslands. In the final year, we quantified standing litter C and N pools in shrub thickets and soil organic matter (SOM), soil organic carbon (SOC), soil total nitrogen (TN) and soil CO2 efflux in shrub thickets and adjacent grasslands. Heavy litterfall resulted in a dense litter layer storing an average of 809 g C m,2 and 36 g N m,2. Although soil CO2 efflux was stimulated by shrub encroachment in younger soils, soil CO2 efflux did not vary between shrub thickets and grasslands in the oldest soils and increases in CO2 efflux in shrub thickets did not offset contributions of increased litterfall to SOC. SOC was 3.6,9.8 times higher beneath shrub thickets than in grassland soils and soil TN was 2.5,7.7 times higher under shrub thickets. Accumulation rates of soil and litter C were highest in the youngest thicket at 101 g m,2 yr,1 and declined with increasing thicket age. Expansion of shrubs on barrier islands, which have low levels of soil carbon and high potential for ANPP, has the potential to significantly increase ecosystem C sequestration. [source] Determinants of vertebrate invasion success in Europe and North AmericaGLOBAL CHANGE BIOLOGY, Issue 9 2006JONATHAN M. JESCHKE Abstract Species that are frequently introduced to an exotic range have a high potential of becoming invasive. Besides propagule pressure, however, no other generally strong determinant of invasion success is known. Although evidence has accumulated that human affiliates (domesticates, pets, human commensals) also have high invasion success, existing studies do not distinguish whether this success can be completely explained by or is partly independent of propagule pressure. Here, we analyze both factors independently, propagule pressure and human affiliation. We also consider a third factor directly related to humans, hunting, and 17 traits on each species' population size and extent, diet, body size, and life history. Our dataset includes all 2362 freshwater fish, mammals, and birds native to Europe or North America. In contrast to most previous studies, we look at the complete invasion process consisting of (1) introduction, (2) establishment, and (3) spread. In this way, we not only consider which of the introduced species became invasive but also which species were introduced. Of the 20 factors tested, propagule pressure and human affiliation were the two strongest determinants of invasion success across all taxa and steps. This was true for multivariate analyses that account for intercorrelations among variables as well as univariate analyses, suggesting that human affiliation influenced invasion success independently of propagule pressure. Some factors affected the different steps of the invasion process antagonistically. For example, game species were much more likely to be introduced to an exotic continent than nonhunted species but tended to be less likely to establish themselves and spread. Such antagonistic effects show the importance of considering the complete invasion process. [source] Civil Servants, Economic Ideas, and Economic Policies: Lessons from ItalyGOVERNANCE, Issue 4 2005LUCIA QUAGLIA Building on theoretically oriented and empirically grounded research on two key macroeconomic institutions in Italy, this article explains how and why civil servants can engineer major policy changes, making a difference in a country's trajectory. Italy provides a challenging testing ground for this kind of analysis, as it is generally portrayed as a highly politicized system in which political parties and politicians fully control public policies. Three general lessons can be learned, the first being that the role of civil servants in changing modes of economic governance depends on the resources that they master in the system in which they operate. "Intangible assets" are of primary importance in complex and perceived technical policies, such as monetary and exchange rate policy, which have high potential for "technocratic capture." Second, in these policies, certain intangible assets, such as specific bodies of economic knowledge or policy paradigms, have a considerable impact on policy making. Third, besides interactions in international fora, the professional training of civil servants is a mainstream way through which economic policy beliefs circulate and gain currency, laying the foundations for policy shifts. By highlighting the importance of the intangible assets of macroeconomic institutions, this research makes an unorthodox contribution to the primarily economic literature on central bank independence. [source] Assessing yield and yield stability of remnant populations of Cenchrus ciliaris L. in arid Tunisia: developing a blueprint for initiating native seed productionGRASS & FORAGE SCIENCE, Issue 3 2008M. Visser Abstract Native seed needs to be sourced locally yet contain ample genetic variation. A blueprint is developed for assembling and assessing native plant material at one eco-geographical site prior to seed multiplication for restoring degraded drylands of North Africa. To satisfy the ,local yet ample' criterion, the feasibility of selecting a limited number of high-yielding genotypes within one starter collection of Cenchrus ciliaris L. in Presaharian Tunisia (100,200 mm annual rainfall) was tested and compared to outcomes with similar work on its ecological complement, Stipa lagascae R. & Sch. Results showed that a limited number of high-yielding genotypes can easily produce quality native seed because of the high genetic diversity of the starter material. Results also showed that there was a high potential to increase the rain-use efficiency of degraded drylands using this seed. Seven ground rules are suggested when building the starter collection: (i) carefully delimit the region for sourcing seed; (ii) work with individual plants; (iii) carefully choose the collection site; (iv) replicate plant material as much as is feasible; (v) match evaluation methods to resource constraints; (vi) wait for conditions of maximum resource availability before culling; and (vii) apply a two-tiered selection strategy. [source] Tris(perfluoroalkyl)silyl Entities as Unexpectedly Potent Tags for the Noncovalent Immobilization of Catalysts by Fluorous,Fluorous Interactions: Application to the Synthesis of Several Perfluoro-Tagged LigandsHELVETICA CHIMICA ACTA, Issue 5 2005Vasyl Andrushko Unexpectedly high retention times were obtained in HPLC investigations for compounds equipped with (C8F17CH2CH2)3Si tags on C8F17 -modified silica gel (Fig.,4). Hence, these tags have a high potential for the noncovalent immobilization of catalysts to be applied in organic solvents, allowing for an easy separation and re-use of the catalyst by filtration and reapplication. The tris(perfluoroalkyl)silyl tag could be incorporated in a straightforward manner into ligands as demonstrated by the synthesis of several prominent classes of ligands (Schemes,4,6). [source] Twelve immunotherapy drugs that could cure cancersIMMUNOLOGICAL REVIEWS, Issue 1 2008Mac' Cheever, Martin A. Summary: Immune T cells can kill cancer cells. Cancer vaccines function by increasing the number of immune T cells. There are exceedingly strict biologic limits imposed on the immune system to prevent excessive T-cell activation and expansion. The same biological restrictions limit cancer vaccines. Immunotherapeutic agents that circumvent the biological restrictions have been invented and formulated, including (i) dendritic cell activators and growth factors, (ii) vaccine adjuvants, (iii) T-cell stimulators and growth factors, (iv) immune checkpoint inhibitors, and (v) agents to neutralize or inhibit suppressive cells, cytokines, and enzymes. Few of these agents are broadly available for the development of effective multiple component regimens. The major problem facing immunotherapy today is a lack of broad availability of agents already in existence. The National Cancer Institute has developed a well-vetted ranked list of agents with high potential to serve as immunotherapeutic drugs. This review focuses on 12 of the agents, all with proven ability to augment T-cell responses. Alone, each has little chance of making substantial inroads into cancer therapy. In combinations dictated by biology, the agents are overwhelmingly likely to have an impact. Future availability of these agents for development of innovative combination cancer therapy regimens will provide a benchmark for the resolve of the national cancer therapy translational research enterprise. [source] Quantitative analysis of MUC1 and MUC5AC mRNA in pancreatic juice for preoperative diagnosis of pancreatic cancerINTERNATIONAL JOURNAL OF CANCER, Issue 2 2006Kenoki Ohuchida Abstract Pancreatic juice is a promising type of diagnostic sample for pancreatic cancer, and members of the mucin (MUC) family are diagnostic candidates. To evaluate the utility of MUC family members as diagnostic markers, we measured MUC mRNA expression in pancreatic tissues and pancreatic juice obtained from patients with different pancreatic diseases as well as in pancreatic cancer cell lines by real-time PCR. Furthermore, to support the possibility of early diagnosis by quantification of MUC1 and MUC5AC, immunohistochemistry and microdissection-based quantitative analysis of mRNA were carried out. There was no significant correlation between MUC1 and MUC5AC expression in cell lines. When ,-actin was used as a reference gene, median MUC1 and MUC5AC mRNA expression levels were remarkably greater in tumoral tissues than in non-tumoral tissues, but median MUC4 and MUC6 mRNA expression levels were not. Receiver operating characteristic curve analysis showed that quantitative analysis of MUC1 and MUC5AC mRNA in pancreatic juice is better diagnostic modality than that of MUC4 and MUC6 mRNA. Immunohistochemistry showed that MUC1 and MUC5AC were highly expressed in invasive ductal carcinomas (IDC) and moderately expressed in high-grade pancreatic intraepithelial neoplasia (PanIN); no staining was observed in normal ducts. Analysis of cells isolated by microdissection showed stepwise upregulation of MUC1 and MUC5AC in the development of high-grade PanIN to IDC. Our results suggest that MUC1 and MUC5AC are upregulated stepwise in pancreatic carcinogenesis and that quantitative assessment of MUC1 and MUC5AC mRNA in pancreatic juice has high potential for preoperative diagnosis of pancreatic cancer. © 2005 Wiley-Liss, Inc. [source] Antimicrobial peptides generated from milk proteins: a survey and prospects for application in the food industry.INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 3 2010A review Milk proteins constitute a natural reservoir of bioactive peptides with physiological and/or antimicrobial properties, the release of which requires hydrolysis of the precursor molecules by digestive proteases or by fermentation with proteolytic micro-organisms. Depending on the digestive or microbial proteases used, an array of bioactive peptides would be released either from caseins or whey proteins, but only a small part of these peptides has so far been identified and characterised with respect to their antimicrobial activity. The antimicrobial peptides known thus far have proven to be potent inhibitors to the growth of a wide range of undesirable micro-organisms of health or spoilage significance. Nevertheless, previous research work has largely been oriented towards their possible application in medicine, which has hindered their high potential as food-grade biopreservatives and/or as supplements in functional foods. This review attempts to study the literature pertaining to antimicrobial peptides derived from major milk proteins (caseins, ,-lactalbumin and ,-lactoglobulin) upon hydrolysis either by digestive proteases or by fermentation with proteolytic lactic acid bacteria. Their possible application in the food industry and their mechanism of action will also be discussed. Reference antimicrobial peptides produced by living micro-organisms as innate immune defence components against microbial infections will occasionally be invoked for comparison purposes. [source] A review on energy, economical, and environmental benefits of the use of CHP systems for small commercial buildings for the North American climateINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 14 2009P. J. Mago Abstract The use of combined heating and power (CHP) systems to produce both electricity and heat is increasing rapidly due to their high potential of reducing primary energy consumption (PEC), cost, and emissions in domestic, commercial, and industrial applications. In addition to producing both electricity and heat, CHP systems can be coupled with vapor compression systems to provide cooling. This paper analyzes a natural gas engine CHP system together with a vapor compression system for different American climate zones. Performance is measured in terms of operational costs, PEC, and carbon dioxide emissions as a percent of a reference building. The objective of this paper is to compare the performance of a CHP system operating 24,h a day with a system that only operates during typical office hours. Furthermore, the system is optimized based on reducing PEC, minimizing costs, and reducing emissions. In addition, the benefits of CHP systems based on the Energy Star program and the Leadership in Energy and Environmental Design (LEED) program are presented. Results show that, in general, it is more beneficial to operate the CHP system during typical office hours than to operate the system 24,h a day. Also, the CHP system performance strongly depends on the location where it is installed. In addition to reductions in cost, primary energy, and emissions, CHP systems can help achieve the Energy Star label for commercial office buildings and help obtain LEED points that go toward achieving LEED certification status. Copyright © 2009 John Wiley & Sons, Ltd. [source] Signal-noise support vector model of a microwave transistorINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 4 2007Filiz Güne Abstract In this work, a support vector machines (SVM) model for the small-signal and noise behaviors of a microwave transistor is presented and compared with its artificial neural network (ANN) model. Convex optimization and generalization properties of SVM are applied to the black-box modeling of a microwave transistor. It has been shown that SVM has a high potential of accurate and efficient device modeling. This is verified by giving a worked example as compared with ANN which is another commonly used modeling technique. It can be concluded that hereafter SVM modeling is a strongly competitive approach against ANN modeling. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007. [source] Photophysiology of Surface Phytoplankton Communities in a Transect from the Mouth of the Peene-Strom to the Arkona Sea (Baltic)INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 5 2003Anna Maria Müller Abstract The potential of surface phytoplankton to withstand photostress was investigated in August 1998 along a transect from the mouth of the Peene-Strom (Pomeranian Bight) to the open Arkona Sea (Baltic). Photosynthetic efficiency, algal class composition and pigment pattern were determined. Algae were photoinhibited by artificial illumination and the kinetics of recovery were recorded. Under photoinhibitory treatment, algae from the estuary showed a low effective quantum yield but a high potential to recover their maximum photosynthetic efficiency. Contrary to this, the relatively high effective quantum yield of open sea algae under photoinhibitory treatment is accompanied by a low final recovery of maximum photosynthetic efficiency. These phenomena are discussed with respect to nutrient supply, algal class composition and to different strategies of algae to react to light stress. Literature data of summer primary productivity of open sea and coastal algae are compared with our data on electron transport rates. This revealed a low influence of photoinhibitory effects on productivity. [source] Implementing a pre-operative checklist to increase patient safety: a 1-year follow-up of personnel attitudesACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2010L. NILSSON Background: The operating room is a complex work environment with a high potential for adverse events. Protocols for perioperative verification processes have increasingly been recommended by professional organizations during the last few years. We assessed personnel attitudes to a pre-operative checklist (,time out') immediately before start of the operative procedure. Methods: ,Time out' was implemented in December 2007 as an additional safety barrier in two Swedish hospitals. One year later, in order to assess how the checklist was perceived, a questionnaire was sent by e-mail to 704 persons in the operating departments, including surgeons, anesthesiologists, operation and anesthetic nurses and nurse assistants. In order to identify differences in response between professions, each alternative in the questionnaire was assigned a numerical value. Results: The questionnaire was answered by 331 (47%) persons and 93% responded that ,time out' contributes to increased patient safety. Eighty-six percent thought that ,time out' gave an opportunity to identify and solve problems. Confirmation of patient identity, correct procedure, correct side and checking of allergies or contagious diseases were considered ,very important' by 78,84% of the responders. Attitudes to checking of patient positioning, allergies and review of potential critical moments were positive but differed significantly between the professions. Attitudes to a similar checklist at the end of surgery were positive and 72,99% agreed to the different elements. Conclusion: Staff attitudes toward a surgical checklist were mostly positive 1 year after their introduction in two large hospitals in central Sweden. [source] Where do the feral oilseed rape populations come from?JOURNAL OF APPLIED ECOLOGY, Issue 2 2008A large-scale study of their possible origin in a farmland area Summary 1Many cultivated species can escape from fields and colonize seminatural habitats as feral populations. Of these, feral oilseed rape is a widespread feature of field margins and roadside verges. Although considered in several studies, the general processes leading to the escape and persistence of feral oilseed rape are still poorly known. Notably, it remains unclear whether these annuals form transient populations resulting mainly from seed immigration (either from neighbouring fields or during seed transport), or whether they show real ability to persist (either through self-recruitment or seed banks). 2We conducted a 4-year large-scale study of factors involved in the presence of feral oilseed rape populations in a typical open-field area of France. The results were subjected to statistical methods suitable for analysing large data sets, based on a regression approach. We subsequently addressed the relative contribution of the ecological processes identified as being involved in the presence of feral populations. 3Many feral oilseed rape populations resulted from seed immigration from neighbouring fields (about 35,40% of the observed feral populations). Immigration occurred at harvest time rather than at sowing. Around 15% of such populations were attributed to immigration through seed transport. 4The other half resulted from processes of persistence, mainly through persistent seed banks (35,40% of the observed feral populations). This was all the more unexpected because seed banks have not yet been documented on road verges (despite being frequent within fields). Local recruitment was rare, accounting for no more than 10% of the feral populations. 5Synthesis and applications. Understanding the dynamics of feral oilseed rape populations is crucial for evaluating gene flow over an agro-ecosystem. Our results show that, while many feral populations do come from annual seed dispersal, a significant number also result from seeds stored in the soil for several years. In the current context of coexistence and management of transgenic with non-transgenic crops, feral persistence and, especially, the seed bank contribution to the dynamics of feral populations need to be considered seriously. The latter, combined with self-recruitment, indicates a high potential for the persistence of transgenes and the possible emergence of gene-stacking. [source] Characterization of a new tyrosinase from Pycnoporus species with high potential for food technological applicationsJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2005S. Halaouli Abstract Aims:, Tyrosinase production by Pycnoporus cinnabarinus and Pycnoporus sanguineus was screened among 20 strains originating from various geographical areas, particularly from tropical environments. The tyrosinase from the most efficient strain was purified and characterized and tested for food additive applications. Methods and Results:, Monophenolase and diphenolase activities of tyrosinase were measured from cell lysate from the 20 Pycnoporus strains, for 8,10 days of cultivation. The strain P. sanguineus CBS 614.73 showed the highest productivity (45·4 and 163·6 U g,1 protein per day for monophenolase and diphenolase respectively). P. sanguineus CBS 614.73 tyrosinase was purified from concentrated cell lysate, anion-exchange, size-exclusion and hydroxyapatite chromatography, with a final yield of 2% and a purification factor of 35,38. The pure enzyme was a monomere with a molecular mass of 45 kDa and it showed four isoforms or isoenzymes with pI between 4·5,5. No N-glycosylation was found. The N-terminal amino acid sequence was IVTGPVGGQTEGAPAPNR. The enzyme was shown to be almost fully active in a pH range of 6,7, in a large temperature range (30,70°C), and was stable below 60°C. The main kinetic constants were determined. The tyrosinase was able to convert p -tyrosol and p -coumaric acid into hydroxytyrosol and caffeic acid, respectively, and it could also catalyse the cross-linking formation of a model protein. Conclusions:, Among the genus Pycnoporus, known for the production of laccase, the strain P. sanguineus CBS 614.73 was shown to produce one other phenoloxidase, a new monomeric tyrosinase with a specific activity of 30 and 84 U mg,1 protein for monophenolase and diphenolase respectively. Significance and Impact of the Study:, This study identified P. sanguineus CBS 614.73 as a potential producer of a tyrosinase which demonstrated effectiveness in the synthesis of antioxidant molecules and in protein cross-linking. [source] Reducing ammonia emission from poultry manure composting via struvite formationJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 6 2007Wenxiu Zhang Abstract Composting can provide a viable alternative for poultry manure management in the Fraser Valley of British Columbia, Canada. However, it has a high potential for ammonia emission because of the high nitrogen content of poultry litter. The objective of this study was to reduce ammonia emission by precipitating ammonia into struvite before it can volatilize from the composting matrix. Nitrogen transformation occurs during composting, but struvite formation can help to conserve nitrogen, and does not allow a large amount of nitrogen to be released into the environment as ammonia or nitrate, because ammonium-nitrogen becomes bound in struvite. It would also be possible to remove phosphorus from the manure. A laboratory-scale experiment was conducted to examine the feasibility of struvite formation during poultry manure composting. Magnesium and phosphate salts were supplemented to create favorable conditions to form struvite. Results indicated that ammonia emission was reduced by 40% to 84%, while the nitrogen retention in compost was enhanced. The struvite formed in compost was confirmed by means of X-ray diffraction; and scanning electron microscopy with energy dispersive X-ray spectroscopy. Copyright © 2007 Society of Chemical Industry [source] Assessment of spring water quality and quantity, and health implications in Tongaren division, Nzoia River catchment, KenyaAFRICAN JOURNAL OF ECOLOGY, Issue 2009G. M. Simiyu Abstract Spring water is the common source of public water supply in most rural communities of developing countries such as Kenya. The water quality and quantity may be altered due to catchments degradation. This study was carried out in Tongaren division, Nzoia River catchment. The aim of this study was to investigate and map the occurrence and distribution of springs and to determine their water quality and quantity. This study determined the spring water discharge, conductivity, turbidity, total and thermotolerant (faecal) coliforms to assess suitability and sustainability of spring water for safe drinking. Twenty-eight springs were identified and their locations mapped using Global Positioning System (GPS) geo-reference data. Discharge ranged from 0.1 to 3 l s,1, with some drying up during dry season. Total coliform was innumerable in most of the studied springs while thermotolerant (faecal) coliform counts occurred in eight springs, including four protected springs. This poses high risks of water-borne diseases. The water should be filtered and boiled prior to use for drinking. Facilitation of communities enabled development of seven springs to enhance water yield and quality. This study established high potential in the communities to develop springs and utilize the spring water as alternative source of livelihoods. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||