Distribution by Scientific Domains
Distribution within Chemistry

Kinds of Chain

  • acid chain
  • acid side chain
  • acyl chain
  • adjacent chain
  • aliphatic chain
  • alkoxy chain
  • alkyl chain
  • alkyl side chain
  • alpha chain
  • amino acid side chain
  • amino side chain
  • amino-acid side chain
  • anionic chain
  • arginine side chain
  • aromatic side chain
  • asp side chain
  • atom chain
  • b chain
  • bayesian markov chain
  • bulky side chain
  • c chain
  • carbohydrate chain
  • carbon chain
  • carlo markov chain
  • causal chain
  • chiral side chain
  • commodity chain
  • conjugated main chain
  • coordination chain
  • copolymer chain
  • dialysis chain
  • different side chain
  • distribution chain
  • dna chain
  • double chain
  • electron transport chain
  • extended chain
  • fatty acid chain
  • flexible chain
  • flexible side chain
  • food chain
  • food supply chain
  • form chain
  • free light chain
  • gamma chain
  • global commodity chain
  • global supply chain
  • global value chain
  • globin chain
  • glycan chain
  • glycol chain
  • glycosaminoglycan chain
  • graft chain
  • grafted chain
  • h chain
  • heavy chain
  • helical chain
  • histidine side chain
  • human food chain
  • hydrocarbon chain
  • hydrogen-bonded chain
  • hydrophilic side chain
  • hydrophobic chain
  • immunoglobulin heavy chain
  • immunoglobulin light chain
  • infinite chain
  • infinite zigzag chain
  • invariant chain
  • isoprenoid side chain
  • jump markov chain
  • kappa light chain
  • lambda light chain
  • laminin chain
  • lateral chain
  • light chain
  • linear chain
  • long alkyl chain
  • long chain
  • longer chain
  • lysine side chain
  • macromolecular chain
  • main chain
  • marine food chain
  • marketing chain
  • markov chain
  • metal atom chain
  • metal chain
  • mitochondrial electron transport chain
  • mitochondrial respiratory chain
  • molecular chain
  • monte carlo markov chain
  • mountain chain
  • myosin heavy chain
  • myosin light chain
  • myosin regulatory light chain
  • n chain
  • oligoethylene glycol chain
  • oligosaccharide chain
  • one-dimensional chain
  • one-dimensional hydrogen-bonded chain
  • one-dimensional zigzag chain
  • ossicular chain
  • parallel chain
  • pcl chain
  • pe chain
  • peg chain
  • peo chain
  • peptide chain
  • peripheral chain
  • plla chain
  • pmma chain
  • pnipam chain
  • polyacetylene chain
  • polyamide chain
  • polyene chain
  • polymer chain
  • polymer main chain
  • polymerase chain
  • polymeric chain
  • polypeptide chain
  • polystyrene chain
  • polystyrene side chain
  • polyubiquitin chain
  • precursor chain
  • production chain
  • protein chain
  • protein side chain
  • proteinogenic side chain
  • ps chain
  • pu chain
  • receptor chain
  • regulatory light chain
  • respiratory chain
  • retail supply chain
  • reversible jump markov chain
  • short chain
  • side chain
  • single chain
  • sinusoidal chain
  • spin chain
  • sugar chain
  • supermarket chain
  • supply chain
  • sympathetic chain
  • transduction chain
  • transport chain
  • trophic chain
  • tryptophan side chain
  • value chain
  • water chain
  • zig-zag chain
  • zigzag chain

  • Terms modified by Chain

  • chain activity
  • chain alkane
  • chain amino acids
  • chain analysis
  • chain antibody
  • chain approach
  • chain architecture
  • chain arrangement
  • chain assembly
  • chain branching
  • chain collapse
  • chain complex
  • chain complex i
  • chain composition
  • chain compound
  • chain conformation
  • chain consisting
  • chain containing
  • chain context
  • chain coordination
  • chain disease
  • chain elongation
  • chain end
  • chain expression
  • chain extender
  • chain extension
  • chain fatty acid
  • chain folding
  • chain fragment
  • chain gene
  • chain gene rearrangement
  • chain growth
  • chain increase
  • chain integration
  • chain interaction
  • chain isoform
  • chain kinase
  • chain length
  • chain length distribution
  • chain locus
  • chain management
  • chain management research
  • chain managers
  • chain mechanism
  • chain microstructure
  • chain migration
  • chain mobility
  • chain model
  • chain models
  • chain monte carlo
  • chain motion
  • chain network
  • chain number
  • chain orientation
  • chain packing
  • chain parallel
  • chain performance
  • chain phosphatase
  • chain phosphorylation
  • chain polymer
  • chain protein
  • chain reaction
  • chain reaction amplification
  • chain reaction analysis
  • chain reaction detection
  • chain reaction method
  • chain reaction methods
  • chain reaction primer
  • chain reaction products
  • chain reaction restriction fragment length polymorphism
  • chain reaction study
  • chain reaction system
  • chain reaction technique
  • chain reaction techniques
  • chain reaction testing
  • chain reaction-denaturing gradient gel electrophoresis
  • chain reaction-restriction fragment length polymorphism
  • chain reaction-restriction fragment length polymorphism analysis
  • chain reaction-restriction fragment length polymorphism method
  • chain reaction-single strand conformation polymorphism
  • chain relaxation
  • chain restriction
  • chain running
  • chain scission
  • chain segment
  • chain sequence
  • chain strategy
  • chain structure
  • chain system
  • chain termination
  • chain terminus
  • chain tracing
  • chain transfer
  • chain transfer agent
  • chain transfer polymerization
  • chain transfer reaction
  • chain triglyceride
  • chain variant

  • Selected Abstracts


    JOURNAL OF FOOD SAFETY, Issue 3 2003
    ABSTRACT The aim of this study was to investigate fecal shedding and transmission of E. coli O157 in cohorts of cattle within a feedlot, to assess subsequent contamination of carcasses with this pathogen and to identify risk factors associated with fecal shedding of E. coli O157. A cohort of 133 heifers housed infour adjacent pens was examined over a five month period, from entering the feedlot to slaughter. Individual rectal fecal samples and pen environmental samples were taken at monthly intervals. The entire outer and inner surfaces of a carcass side of each animal were swabbed immediately following slaughter. E. coli O157 was isolated from 136 (23%) of the 600 rectal fecal samples; 96% of which contained virulent markers. One hundred and sixty environmental samples were examined and E. coli O157 was isolated from 46 (29%), all of which contained virulent markers. E. coli O157 was not isolated from any of the dressed carcasses. The prevalence of E. coli O157 fecal shedding may be related to the pen and E. coli O157 contamination of the pen floor feces, water trough and feed. E. coli O157 should be considered as a pathogen shed in the feces of a substantial proportion of feedlot cattle. However, with good hygienic practice at harvest, a very low level of this pathogen can be achieved on dressed carcasses. [source]


    A. Place
    Recently, very-long-chain (C28) highly unsaturated fatty acids (VLC-HUFA) were identified in seven marine dinoflagellate species (Manour et al., Phytochemistry, 1999, 50: 541,548). In general, the proportion of these fatty acids accounted for less than 2.3% of the total fatty acids in these species. As part of a study investigating the modulation of the hemolytic fatty acid 18:5n3, cultures of Prorocentrum mininum were grown in artificial seawater with varying molarities of sodium selenite (0, 1, 10, and 100 nM). Optimal growth was observed at 1 nM with this media. As expected, the level of 18:5n3 was modulated by the selenium in the culture medium (7.0 0.2, 14.5 0.6, 7.4 0.8, and 3.9 0.8% of total fatty acid, respectively), with the highest percentage found at 1 nM. Unexpectedly the level of VLC-HUFA (28:8n3) increased to 7.3 2.8% at 0 nM sodium selenite, while at all other selenite concentrations the VLC-HUFA was less than 1%. A possible biochemical basis for this finding will be discussed. [source]


    Cyclicality is a well-known and accepted fact of life in market-driven economies. Less well known or understood, however, is the phenomenon of amplification as one looks "upstream" in the industrial supply chain. We examine the amplification phenomenon and its implications through the lens of one upstream industry that is notorious for the intensity of the business cycles it faces: the machine tool industry. Amplification of demand volatility in capital equipment supply chains, e. g., machine tools, is particularly large relative to that seen in distribution and component parts supply chains. We present a system dynamics simulation model to capture demand volatility amplification in capital supply chains. We explore the lead-time, inventory, production, productivity, and staffing implications of these dynamic forces. Several results stand out. First, volatility hurts productivity and lowers average worker experience. Second, even though machine tool builders can do little to reduce the volatility in their order streams through choice of forecast rule, a smoother forecasting policy will lead companies to retain more of their skilled work force. This retention of skilled employees is often cited as one of the advantages that European and Japanese companies have had relative to their U. S. competitors. Our results suggest some insights for supply chain design and management: downstream customers can do a great deal to reduce the volatility for upstream suppliers through their choice of order forecast rule. In particular, companies that use smoother forecasting policies tend to impose less of their own volatility upon their supply base and may consequently enjoy system-wide cost reduction. [source]


    ABSTRACT. The population dynamics in a food chain are derived from a sequence of short-run equilibria of an ecosystem where predator species demand prey biomass, supply own biomass to their predators and are assumed to behave as if they maximize net biomass intake. Introducing prices as scarcity indicators for the biomass of each species enables us to determine a short-run ecosystem equilibrium guided by prices. Equilibrium regimes differ with respect to their mix of zero-priced (= abundant) and positive-priced (= scarce) species. The population dynamics turn out to vary with the prevailing equilibrium regime. Our analysis yields a richer and more complex population dynamics than the traditional predator-prey dynamics of the Lotka-Volterra type. [source]


    Tsugio Ide
    Banning unfair trade practices stands alongside private monopolization and the unjust restraint of trade as a key theme in competition policy. However, it poses much greater difficulties to deal with the matter than either private monopolization or unjust restraint of trade. In recent years, ongoing economic globalization, advances in information communication technology and other factors have wrought major changes in the traditional supply chain: for example, in subcontracting structure. Given the role of small and medium enterprises in underpinning economic growth, lifting the basic quality and performance level of these firms and improving business conditions for them have emerged as key policy themes. New efforts are needed to establish fair trade as a business practice and to create a new business culture in corporation with competition policy, small and medium enterprise policy and business ethics, such as Corporate Social Responsibility (CSR) practices. [source]


    First page of article [source]

    Supply Chain Conflict Due to Store Brands: The Value of Wholesale Price Commitment in a Retail Supply Chain,

    DECISION SCIENCES, Issue 2 2010
    Ana Groznik
    ABSTRACT Store brands are of increasing importance in retail supply chains, often causing channel conflict, as the retailer's product directly competes with the manufacturer's national brand. Extant research on the resulting channel interactions either assumes the national brand manufacturer can credibly commit to maintaining a wholesale price or that he lacks such ability. However, these two scenarios imply very different supply chain interactions, as only a national brand manufacturer with commitment ability can strategically adjust a national brand wholesale price to prevent a store brand introduction by the retailer. We specifically analyze the impact of this assumption on the manufacturer, the retailer, and the customers. We determine when long-term contracts that provide the manufacturer with such commitment ability can improve supply chain profitability. [source]

    Supply Management Under High Goal Incongruence: An Empirical Examination of Disintermediation in the Aerospace Supply Chain

    DECISION SCIENCES, Issue 3 2008
    Christian L. Rossetti
    ABSTRACT Aftermarket sales and profits are becoming an increasingly important part of an original equipment manufacturer's (OEM) business model. Because replacement parts often do not require further manufacturing, OEMs act as intermediaries in the aftermarket. As with any intermediary, the OEM must concern itself with suppliers disintermediating its supply chain selling replacement parts directly to the OEM's customers. We frame supply chain disintermediation (SCD) as a principal,agent contracting problem between an OEM buyer and a supplier. Hypotheses relate contract conditions, goal incongruence, supplier capabilities and contract enforcement to SCD. The data are collected from the aerospace industry using a multimethod study, combining an Internet-based survey with archival data. Causal modeling with structural equation modeling (SEM) shows general support for the hypotheses. Particularly, SCD is positively related to buyer,supplier goal incongruence. The agency model offers insights that differ from previous transaction-cost-based models of buyer,supplier relationships. OEM buyers with a lucrative aftermarket should consider aligning goals through incentives rather than relying entirely on economic hostages associated with specific assets. [source]

    Channel Coordination for a Supply Chain with a Risk-Neutral Manufacturer and a Loss-Averse Retailer,

    DECISION SCIENCES, Issue 3 2007
    Charles X. Wang
    ABSTRACT This articles considers a decentralized supply chain in which a single manufacturer is selling a perishable product to a single retailer facing uncertain demand. It differs from traditional supply chain contract models in two ways. First, while traditional supply chain models are based on risk neutrality, this article takes the viewpoint of behavioral principal,agency theory and assumes the manufacturer is risk neutral and the retailer is loss averse. Second, while gain/loss (GL) sharing is common in practice, there is a lack of analysis of GL-sharing contracts in the supply chain contract literature. This article investigates the role of a GL-sharing provision for mitigating the loss-aversion effect, which drives down the retailer order quantity and total supply chain profit. We analyze contracts that include GL-sharing-and-buyback (GLB) credit provisions as well as the special cases of GL contracts and buyback contracts. Our analytical and numerical results lend insight into how a manufacturer can design a contract to improve total supply chain, manufacturer, and retailer performance. In particular, we show that there exists a special class of distribution-free GLB contracts that can coordinate the supply chain and arbitrarily allocate the expected supply chain profit between the manufacturer and retailer; in contrast with other contracts, the parameter values for contracts in this class do not depend on the probability distribution of market demand. This feature is meaningful in practice because (i) the probability distribution of demand faced by a retailer is typically unknown by the manufacturer and (ii) a manufacturer can offer the same contract to multiple noncompeting retailers that differ by demand distribution and still coordinate the supply chains. [source]

    e-Integration in the Supply Chain: Barriers and Performance,

    DECISION SCIENCES, Issue 4 2002
    Markham T. Frohlich
    ABSTRACT Current opinion holds that Internet-based supply chain integration with upstream suppliers and downstream customers (called "e-integration" in this paper) is superior to traditional ways of doing business. This proposition remains untested, however, and similarly we know little about what are the upstream, internal, and downstream barriers to implementing e-integration. This paper empirically addressed these questions using data from a large single nation study, and found (1) a positive link between e-integration and performance, and (2) that internal barriers impeded e-integration more than either upstream supplier barriers or downstream customer barriers. Findings from this study contribute to our theoretical understanding of implementing change in contemporary supply chains, and have important implications for manufacturers interested in improving their supply chain's performance using the Internet. [source]

    The Impact of Forecast Errors on Early Order Commitment in a Supply Chain,

    DECISION SCIENCES, Issue 2 2002
    Xiande Zhao
    ABSTRACT Supply chain partnership involves mutual commitments among participating firms. One example is early order commitment, wherein a retailer commits to purchase a fixed-order quantity and delivery time from a supplier before the real need takes place. This paper explores the value of practicing early order commitment in the supply chain. We investigate the complex interactions between early order commitment and forecast errors by simulating a supply chain with one capacitated supplier and multiple retailers under demand uncertainty. We found that practicing early order commitment can generate significant savings in the supply chain, but the benefits are only valid within a range of order commitment periods. Different components of forecast errors have different cost implications to the supplier and the retailers. The presence of trend in the demand increases the total supply chain cost, but makes early order commitment more appealing. The more retailers sharing the same supplier, the more valuable for the supply chain to practice early order commitment. Except in cases where little capacity cushion is available, our findings are relatively consistent in the environments where cost structure, number of retailers, capacity utilization, and capacity policy are varied. [source]

    Characterization of "Cd10S4(SPh)12", the Thermal Decomposition Product of (NMe4)4[Cd10S4(SPh)16]: Synthesis of a Neutral Cd54 Sulfide Cluster and of a Polymeric Chain of Thiolate-Bridged Cd17 Sulfide Clusters

    Maria Bendova
    Abstract Contrary to claims in the literature that a cluster of the composition of "Cd10S4(SPh)12" was formed by thermal treatment of (NMe4)4[Cd10S4(SPh)16], experimental evidence was gathered that the core structure of the cluster is not exclusively retained and other CdS species are also formed. When "Cd10S4(SPh)12" was treated with PhSH/NEt3 only a part of the material was converted into (NHEt3)4[Cd10S4(SPh)16]. From solutions of "Cd10S4(SPh)12" in strongly coordinating solvents the new neutral CdS clusters Cd54S28(SPh)52Lx (L = pyridine, DMSO or DMF) and [Cd17S4(SPh)26py], were crystallized. The latter forms polymeric chains of phenylthiolate-bridged Cd17 units. [source]

    Unusual Magnetism of an Unsymmetrical Trinickel Chain

    F. Albert Cotton
    Abstract An extended metal atom chain (EMAC) compound with an unsymmetrical trinickel core and the formula [Ni3(dpa)4(CH3CN)](PF6)22CH2Cl2 (12CH2Cl2, dpa is the anion of 2,2,-dipyridylamine) has the central Ni atom in an essentially square-planar configuration. Besides having four equatorial nitrogen atoms, the two terminal metal centers have axial interactions that are notably different with one having a strongly bound acetonitrile molecule with a Ni(3),N(3) distance of 2.108(5) while the other unit has a very weak interaction with an axial PF6 anion [Ni(1)F(1) separation of 2.690 ]. In these outer units, the Ni(3) atom is pulled out of the idealized plane of the four equatorial nitrogen atoms by 0.239 , while in the one with an axial PF6 anion the metal atom is pulled from the plane of the equatorial nitrogen atoms by only 0.097 . In 1 there are two unpaired electrons and an S = 1 state prevails from ca. 25 to 300 K. This magnetic behavior differs considerably from that of symmetrical trinickel EMACs with two strongly pyramidal terminal nickel atoms. A discussion of the effect of various axial ligands on the geometry of the terminal nickel atoms is provided. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]

    Unusual T4(1) Water Chain Stabilized in the One-Dimensional Chains of a Copper(II) Coordination Polymer

    Yi Jin
    Abstract A novel T4(1) water chain in a new CuII coordination polymer, {[Cu(C4H6N2)2(C4H2O4)] (H2O)3}n (1, where C4H6N2 = 2-methylimidazole, C4H2O4 = maleate), has been synthesized and structurally characterized by single-crystal X-ray diffraction. Thermogravimetry, infrared spectroscopy, elemental analysis, and magnetic analysis have also been used to characterize 1. Complex 1 crystallizes in the trigonal space group P3221, and the 1-D chains composed of cyclic water tetramers play an important role in stabilizing the overall polymeric structure. Furthermore, this 1-D water chain presents an unusual association mode of water molecules.( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]

    A Crystalline Phase Transition and Optical Properties in a CoIICuII Oxamato-Bridged Ferrimagnetic Chain

    Cynthia L. M. Pereira
    Abstract The compound [CoCu(opba)(DMSO)3] (1) [opba = ortho -phenylenebis(oxamato)] has been synthesized and characterized. Its crystal structure has been analyzed by X-ray diffraction techniques at 100 and 298 K. A structural phase-transition has been detected at around 150 K. An orthorhombic crystalline system is found at both temperatures, with very similar unit-cell dimensions. At room temperature 1 crystallizes in the Pnam space group (, -1 phase), with a = 7.6712(2), b = 14.8003(3), c = 21.0028(5) , and Z = 4, whereas at low temperature it crystallizes in the Pna21 space group (, -1 phase), with a = 7.3530(2), b = 14.5928(4), c = 21.0510(7) , and Z = 4. Both crystalline phases consist of linearly ordered bimetallic chains with the [Cu(opba)]2, units tied by CoII ions to form a one-dimensional system. The DMSO molecules in , -1, which are coordinated to either CuII or CoII, are disordered. At low temperature, a small reorganization of the CuII and CoII environments is observed. The origin of this phase transition, which is completely reversible, is the modification of the crystalline packing with the temperature. Linear birefringence measurements were done on single crystals in the 100,300 K temperature range. Around 150 K, the linear birefringence curve shows an inflexion that is interpreted as being related to the conversion of ,-1 into , -1. Both dc and ac magnetic measurements were performed on the polycrystalline sample. The results reveal a one-dimensional ferrimagnetic behavior. Single crystal optical characterization at room temperature shows that 1 presents a very strong dichroism superposed on the linear birefringence. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]

    Influences of the Process Chain on the Fatigue Behavior of Samples with Tension Screw Geometry,

    Marcus Klein
    To analyze the influence of the material batch, the structure of the manufacturing process chain, and the process parameters, four different material batches of the quenched and tempered steel SAE 4140 were used to manufacture samples with tension screw geometry. Five different, manufacturing process chains, consisting of the process steps heat treatment, turning, and grinding, were applied. After selected process steps, light and SEM micrographs as well as fatigue experiments were performed. The process itself as well as the process parameters influences the properties of the surface layers and the fatigue behavior in a characteristic manner. For example the variation of the feed rate and cutting speed in the hard-turning process leads to significantly different mechanical properties of the surface layers and residual stress states, which could be correlated with the fatigue behavior. The cyclic deformation behavior of the investigated components can be benchmarked equivalently with stress,strain hysteresis as well as high precision temperature and electrical resistance measurements. The temperature and electrical resistance measurements are suitable for component applications and provide an enormous advantage of information about the fatigue behavior. The temperature changes of the failed areas of the samples with tension screw geometry were significantly higher, a reliable identification of endangered areas is thereby possible. A new test procedure, developed at the Institute of Materials Science and Engineering of the University of Kaiserslautern, with inserted load-free-states during constant amplitude loading, provides the opportunity to detect proceeding fatigue damage in components during inspections. [source]

    2,3-Di- n -undecylanthracene and 2,3-Di- n -decyloxyanthracene (DDOA) , on the Connecting Link between the Aromatic Substrate and the Aliphatic Chain in Self-Assembling Systems

    Henning Hopf
    Abstract In contrast to its bis(oxa) analog 1 (DDOA), the hydrocarbon 11 was not found to form organogels with linear alcohols, alkanes, toluene, acetonitrile and other solvents. Whereas the photoreactivity of 1 did not follow the usual behaviour of anthracene derivatives, compound 11, irradiated in cyclohexane, produced the two expected [4+4]cycloadducts 12 and 13 (anti and syn photodimers, respectively). These facts point to the role of the connecting link between the rigid core and the flexible chain for some self-assembled systems.( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]

    Process Chain for Tailoring the Refractive Index of Thermoplastic Optical Materials using Ceramic Nanoparticles

    E. Ritzhaupt-Kleissl
    Interconnections between active optical devices like laser diodes and polymer optical fibres are a crucial factor of optical damping due to coupling losses at the interfaces. Tailoring the refractive index of thermoplastic polymers can diminish these damping losses. The use of modified thermoplastics in an injection moulding process allows a high throughput and therefore a cost effective method for manufacturing passive optical parts with improved properties. [source]

    Air-Operable, High-Mobility Organic Transistors with Semifluorinated Side Chains and Unsubstituted Naphthalenetetracarboxylic Diimide Cores: High Mobility and Environmental and Bias Stress Stability from the Perfluorooctylpropyl Side Chain

    Byung Jun Jung
    Abstract N,N,-bis(3-(perfluoroctyl)propyl)-1,4,5,8-naphthalenetetracarboxylic acid diimide (8,3-NTCDI) was newly synthesized, as were related fluorooctylalkyl-NTCDIs and alkyl-NTCDIs. The 8,3-NTCDI-based organic thin-film transistor (OTFT) on an octadecyltrimethoxysilane (OTS)-treated Si/SiO2 substrate shows apparent electron mobility approaching 0.7 cm2 V -1s -1 in air. The fluorooctylethyl-NTCDI (8,2-NTCDI) and fluorooctylbutyl-NTCDI (8,4-NTCDI) had significantly inferior properties even though their chemical structures are only slightly different, and nonfluorinated decyl and undecyl NTCDIs did not operate predictably in air. From atomic force microscopy, the 8,3-NTCDI active layer deposited with the substrate at 120 C forms a polycrystalline film with grain sizes >4,m. Mobilities were stable in air for one week. After 100 days in air, the average mobility of three OTFTs decreased from 0.62 to 0.12 cm2 V -1s -1, but stabilized thereafter. The threshold voltage (VT) increased by 15 V in air, but only by 3 V under nitrogen, after one week. On/off ratios were stable in air throughout. We also investigated transistor stability to gate bias stress. The transistor on hexamethlydisilazane (HMDS) is more stable than that on OTS with mobility comparable to amorphous Si TFTs. VT shifts caused by ON (30 V) and OFF (,20 V) gate bias stress for the HMDS samples for 1 hour were 1.79 V and 1.27 V under N2, respectively, and relaxation times of 106 and 107 s were obtained using the stretched exponential model. These performances are promising for use in transparent display backplanes. [source]

    Measuring and partitioning the high-order linkage disequilibrium by multiple order Markov chains

    Yunjung Kim
    Abstract A map of the background levels of disequilibrium between nearby markers can be useful for association mapping studies. In order to assess the background levels of linkage disequilibrium (LD), multilocus LD measures are more advantageous than pairwise LD measures because the combined analysis of pairwise LD measures is not adequate to detect simultaneous allele associations among multiple markers. Various multilocus LD measures based on haplotypes have been proposed. However, most of these measures provide a single index of association among multiple markers and does not reveal the complex patterns and different levels of LD structure. In this paper, we employ non-homogeneous, multiple order Markov Chain models as a statistical framework to measure and partition the LD among multiple markers into components due to different orders of marker associations. Using a sliding window of multiple markers on phased haplotype data, we compute corresponding likelihoods for different Markov Chain (MC) orders in each window. The log-likelihood difference between the lowest MC order model (MC0) and the highest MC order model in each window is used as a measure of the total LD or the overall deviation from the gametic equilibrium for the window. Then, we partition the total LD into lower order disequilibria and estimate the effects from two-, three-, and higher order disequilibria. The relationship between different orders of LD and the log-likelihood difference involving two different orders of MC models are explored. By applying our method to the phased haplotype data in the ENCODE regions of the HapMap project, we are able to identify high/low multilocus LD regions. Our results reveal that the most LD in the HapMap data is attributed to the LD between adjacent pairs of markers across the whole region. LD between adjacent pairs of markers appears to be more significant in high multilocus LD regions than in low multilocus LD regions. We also find that as the multilocus total LD increases, the effects of high-order LD tends to get weaker due to the lack of observed multilocus haplotypes. The overall estimates of first, second, third, and fourth order LD across the ENCODE regions are 64, 23, 9, and 3%. Genet. Epidemiol. 2008. 2008 Wiley-Liss, Inc. [source]

    Geoelectric dimensionality in complex geological areas: application to the Spanish Betic Chain

    Anna Mart
    SUMMARY Rotational invariants of the magnetotelluric impedance tensor may be used to obtain information on the geometry of underlying geological structures. The set of invariants proposed by Weaver et al. (2000) allows the determination of a suitable dimensionality for the modelling of observed data. The application of the invariants to real data must take into account the errors in the data and also the fact that geoelectric structures in the Earth will not exactly fit 1-D, 2-D or simple 3-D models. In this work we propose a method to estimate the dimensionality of geoelectric structures based on the rotational invariants, bearing in mind the experimental error of real data. A data set from the Betic Chain (Spain) is considered. We compare the errors of the invariants estimated by different approaches: classical error propagation, generation of random Gaussian noise and bootstrap resampling, and we investigate the matter of the threshold value to be used in the determination of dimensionality. We conclude that the errors of the invariants can be properly estimated by classical error propagation, but the generation of random values is better to ensure stability in the errors of strike direction and distortion parameters. The use of a threshold value between 0.1 and 0.15 is recommended for real data of medium to high quality. The results for the Betic Chain show that the general behaviour is 3-D with a disposition of 2-D structures, which may be correlated with the nature of the crust of the region. [source]

    Combined Chemical-Enzymatic Assembly of Aminoglycoside Derivatives with N-1-AHB Side Chain

    Igor Nudelman
    Abstract A series of unprotected pseudo-disaccharides and pseudo-trisaccharides of 2-deoxystreptamine-containing aminoglycosides have been selectively acylated at the N-1 position with the valuable (S)-4-amino-2-hydroxybutanoyl (AHB) pharmacophore by using the recombinant BtrH and BtrG enzymes from butirosin biosynthesis in combination with a synthetic acyl donor. The process was optimized by performing two enzymatic steps in a sequential manner without purification of the intermediate product. [source]

    An Approach to Evaluating the Missing Data Assumptions of the Chain and Post-stratification Equating Methods for the NEAT Design

    Paul W. Holland
    Two important types of observed score equating (OSE) methods for the non-equivalent groups with Anchor Test (NEAT) design are chain equating (CE) and post-stratification equating (PSE). CE and PSE reflect two distinctly different ways of using the information provided by the anchor test for computing OSE functions. Both types of methods include linear and nonlinear equating functions. In practical situations, it is known that the PSE and CE methods will give different results when the two groups of examinees differ on the anchor test. However, given that both types of methods are justified as OSE methods by making different assumptions about the missing data in the NEAT design, it is difficult to conclude which, if either, of the two is more correct in a particular situation. This study compares the predictions of the PSE and CE assumptions for the missing data using a special data set for which the usually missing data are available. Our results indicate that in an equating setting where the linking function is decidedly non-linear and CE and PSE ought to be different, both sets of predictions are quite similar but those for CE are slightly more accurate. [source]

    Correction to Malcolm Bourne paper, "Selection and Use of Postharvest Technologies as a Component of the Food Chain", p CRH43 in March issue

    Article first published online: 31 MAY 200
    No abstract is available for this article. [source]

    Food Waste Management by Life Cycle Assessment of the Food Chain

    ABSTRACT: In the past, environmental activities in the food industry used to be focused on meeting the requirements set by authorities on waste and sewage disposal and, more recently, regarding emissions to air. Today environmental issues are considered an essential part of the corporate image in progressive food industries. To avoid sub-optimization, food waste management should involve assessing the environmental impact of the whole food chain. Life cycle assessment (LCA) is an ISO-standardized method to assess the environmental impact of a food product. It evaluates the resources used to perform the different activities through the chain of production from raw material to the user step. It also summarizes the emission/waste to air, water, and land from the same activities throughout the chain. These emissions are then related to the major environmental concerns such as eutrophication, acidification, and ecotoxicity, the factors most relevant for the food sector. The food industry uses the LCAs to identify the steps in the food chain that have the largest impact on the environment in order to target the improvement efforts. It is then used to choose among alternatives in the selection of raw materials, packaging material, and other inputs as well as waste management strategies. A large number of food production chains have been assessed by LCAs over the years. This will be exemplified by a comparison of the environmental impact of ecologically grown raw materials to those conventionally grown. Today LCA is often integrated into process and product development, for example, in a project for reduction of water usage and waste valorization in a diversified dairy. [source]

    Selection and Use of Postharvest Technologies as a Component of the Food Chain

    ABSTRACT: Postharvest technologies refer to the stabilization and storage of unprocessed or minimally processed foods from the time of harvest until final preparation for human consumption. There is a special emphasis on seasonal crops, and simple, labor-intensive, capital-sparing technologies suitable for developing countries where food spoilage rates are high and malnutrition is prevalent. The first step is to determine the major spoilage vectors for each type of food and then identify a technology that will control that vector. For cereal grains the major spoilage vectors are mold, insects, rodents, and other vertebrate pests. Mold is controlled by prompt and adequate drying to a water activity below 0.7. Insects are controlled by good housekeeping, and use of insecticides and fumigants. Rodents are controlled by baits, traps, fumigants, and rodent-proof storage structures. For fruits, vegetables, roots, and tubers the main spoilage vectors are bruising, rotting, senescence, and wilting. Bruising is avoided by careful handling and use of shock-resistant packaging. Rotting is controlled by good housekeeping, gentle handling to avoid breaking the skin, cool storage, and use of preservatives. Senescence is retarded by cold storage or controlled-atmosphere storage. Wilting is controlled by high humidity and cold storage. Growth of microbes is the major spoilage of fish and other foods of animal origin. This is controlled by refrigerated or frozen storage, drying, freezing, or canning. Most spoilage vectors accelerate as the temperature and humidity increase; this makes it more difficult to control spoilage in tropical than in temperate regions. [source]

    Correction to Malcolm Bourne paper, "Selection and Use of Postharvest Technologies as a Component of the Food Chain", p CRH43 in March issue

    Article first published online: 28 JUN 200
    First page of article [source]

    Developing Web-based Interdisciplinary Modules to Teach Solid Waste/Residue Management in the Food Chain

    C.W. Shanklin
    ABSTRACT: A Web-based interdisciplinary instructional resource was developed to provide information that will increase food science educators' knowledge of waste management in the food chain. The 4 modules are: legal implications for management of wastes/residues; identification, quantification, and characterization of wastes/residues; management of wastes/residues; and economic ramifications of wastes/residues. Instructional materials are available for faculty and GTAs for use in teaching the 4 modules. Food science educators can use this Web-based instructional tool as an educational resource in their undergraduate classes to enhance students' knowledge and ability to solve critical environmental problems in the food chain. See [source]

    Pollution and Cost in the Coke-Making Supply Chain in Shanxi Province, China

    Applying an Integrated System Model to Siting, Transportation Trade-Offs
    Summary An integrated system trade-off model has been developed to assess costs and pollution associated with transportation in the coke-making supply chain in Shanxi Province, China. A transportation-flow, cost-minimization solver is combined with models for calculating coke-making plant costs, estimating transportation costs from a geographic information system road and rail database, and aggregating coke-making capacity among plants. Model outputs of economic cost, nitrogen oxides (NOx) emissions, and transport distributions are visualized using an Internet-based graphic user interface. Data for the model were collected on survey trips to Shanxi Province as well as from secondary references and proxies. The modularity and extensibility of the system trade-off model facilitate introduction of new data sets in order to examine various planning scenarios. Scenarios of coke-making plant aggregation, rail infrastructure improvement, and technology transfer were evaluated using the model. Costs and pollution emissions can be reduced by enlarging coke-making plants near the rail stations and closing down other plants. Preferential minimization of transportation costs gives a lower total cost than simply minimizing plant costs. Therefore, policy makers should consider transportation costs when planning the reallocation of coke-making capacity in Shanxi Province. Increasing rail-transport capacity is less effective than aggregating plant capacity. On the other hand, transfer of low-pollution truck technology results in a large emission reduction, however, reflecting the importance of truck transportation in the Shanxi Province coke-making industry. [source]

    The Endogenous Amine 1-Methyl-1,2,3,4- Tetrahydroisoquinoline Prevents the Inhibition of Complex I of the Respiratory Chain Produced by MPP+

    Juan Parrado
    Abstract : The endogenous monoamine 1-methyl-1,2,3,4-tetrahydroisoquinoline has been shown to prevent the neurotoxic effect of MPP+ and other endogenous neurotoxins, which produce a parkinsonian-like syndrome in humans. We have tested its potential protective effect in vivo by measuring the protection of 1-methyl-1,2,3,4-tetrahydroisoquinoline in the neurotoxicity elicited by MPP+ in rat striatum by tyrosine hydroxylase immunocytochemistry. Because we know that cellular damage caused by MPP+ is primarily the result of mitochondrial respiratory inhibition at the complex I level, we have extended the study further to understand this protective mechanism. We found that the inhibitory effect on the mitochondrial respiration rate induced by MPP+ in isolated rat liver mitochondria and striatal synaptosomes was prevented by addition of 1-methyl-1,2,3,4-tetrahydroisoquinoline. This compound has no antioxidant capacity ; therefore, this property is not involved in its protective effect. Thus, we postulate that the preventive effect that 1-methyl-1,2,3,4-tetrahydroisoquinoline has on mitochondrial inhibition for MPP+ could be due to a "shielding effect," protecting the energetic machinery, thus preventing energetic failure. These results suggest that this endogenous amine may protect against the effect of several parkinsonism-inducing compounds that are associated with progressive impairment of the mitochondrial function. [source]