|
| ||
|
|
||
Biochemical Reactions (biochemical + reaction)
Terms modified by Biochemical Reactions Selected AbstractsInhibition of Biochemical Reactions by Silicon Nanowires through Modulating Enzyme ActivitiesCHEMBIOCHEM, Issue 11 2007Changqing Yi Through the wire. We have investigated the potential effects of silicon nanowires (SiNW-SiO2) and SiNWs functionalized with carboxylic groups (SiNW-COOH) on restriction endonucleases and Taq DNA polymerase. The results show that these SiNWs can inhibit enzyme activity (lower band in gel). Our findings suggest that this could be due to chemical interactions between the functional groups on SiNWs and the enzymes. [source] Low Potential Detection of NADH at Titanium-Containing MCM-41,Modified Glassy Carbon ElectrodeELECTROANALYSIS, Issue 5 2007Zhihui Dai Abstract Titanium-containing MCM-41 (Ti-MCM-41) modified glassy carbon electrode (GCE) can exhibit an excellent electrocatalytic activity towards the oxidation of ,-Nicotinamide adenine dinucleotide (NADH). A dramatic decrease in the over-voltage of NADH oxidation reaction is observed at 0.28,V (vs. SCE). The modified electrode is found to be stable and reproducible. The electrode shows a linear response for a wide range of 10,1200,,M NADH and the detection limit is 8.0,,M. Ti-MCM-41 mesoporous molecular sieves provide an efficient matrix for development of NADH biosensors and the prepared electrode not only can be used to detect the concentration of NADH in biochemical reaction, but also as the potential matrix of the construction of dehydrogenases biosensor. [source] Constrained least squares methods for estimating reaction rate constants from spectroscopic dataJOURNAL OF CHEMOMETRICS, Issue 1 2002Sabina Bijlsma Abstract Model errors, experimental errors and instrumental noise influence the accuracy of reaction rate constant estimates obtained from spectral data recorded in time during a chemical reaction. In order to improve the accuracy, which can be divided into the precision and bias of reaction rate constant estimates, constraints can be used within the estimation procedure. The impact of different constraints on the accuracy of reaction rate constant estimates has been investigated using classical curve resolution (CCR). Different types of constraints can be used in CCR. For example, if pure spectra of reacting absorbing species are known in advance, this knowledge can be used explicitly. Also, the fact that pure spectra of reacting absorbing species are non-negative is a constraint that can be used in CCR. Experimental data have been obtained from UV-vis spectra taken in time of a biochemical reaction. From the experimental data, reaction rate constants and pure spectra were estimated with and without implementation of constraints in CCR. Because only the precision of reaction rate constant estimates could be investigated using the experimental data, simulations were set up that were similar to the experimental data in order to additionally investigate the bias of reaction rate constant estimates. From the results of the simulated data it is concluded that the use of constraints does not result self-evidently in an improvement in the accuracy of rate constant estimates. Guidelines for using constraints are given. Copyright © 2002 John Wiley & Sons, Ltd. [source] Salt-resistant and salt-sensitive wheat genotypes show similar biochemical reaction at protein level in the first phase of salt stressJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2006Muhammad Saqib Abstract Salinity has a two-phase effect on plant growth, an osmotic effect due to salts in the outside solution and ion toxicity in a second phase due to salt build-up in transpiring leaves. To elucidate salt-resistance mechanisms in the first phase of salt stress, we studied the biochemical reaction of salt-resistant and salt-sensitive wheat (Triticum aestivum L.) genotypes at protein level after 10 d exposure to 125 mM,NaCl salinity (first phase of salt stress) and the variation of salt resistance among the genotypes after 30 d exposure to 125 mM,NaCl salinity (second phase of salt stress) in solution culture experiments in a growth chamber. The three genotypes differed significantly in absolute and relative shoot and root dry weights after 30 d exposure to NaCl salinity. SARC-1 produced the maximum and 7-Cerros the minimum shoot dry weights under salinity relative to control. A highly significant negative correlation (r2 = ,0.99) was observed between salt resistance (% shoot dry weight under salinity relative to control) and shoot Na+ concentration of the wheat genotypes studied. However, the salt-resistant and salt-sensitive genotypes showed a similar biochemical reaction at the level of proteins after 10 d exposure to 125 mM NaCl. In both genotypes, the expression of more than 50% proteins was changed, but the difference between the genotypes in various categories of protein change (up-regulated, down-regulated, disappeared, and new-appeared) was only 1%,8%. It is concluded that the initial biochemical reaction to salinity at protein level in wheat is an unspecific response and not a specific adaptation to salinity. [source] Integration of a Chemical-Responsive Hydrogel into a Porous Silicon Photonic Sensor for Visual Colorimetric ReadoutADVANCED FUNCTIONAL MATERIALS, Issue 4 2010Lisa M. Bonanno Abstract The incorporation of a chemo-responsive hydrogel into a 1D photonic porous silicon (PSi) transducer is demonstrated. A versatile hydrogel backbone is designed via the synthesis of an amine-functionalized polyacrylamide copolymer where further amine-specific biochemical reactions can enable control of cross-links between copolymer chains based on complementary target,probe systems. As an initial demonstration, the incorporation of disulfide chemistry to control cross-linking of this hydrogel system within a PSi Bragg mirror sensor is reported. Direct optical monitoring of a characteristic peak in the white light reflectivity spectrum of the incorporated PSi Bragg mirror facilitates real-time detection of the hydrogel dissolution in response to the target analyte (reducing agent) over a timescale of minutes. The hybrid sensor response characteristics are shown to systematically depend on hydrogel cross-linking density and applied target analyte concentration. Additionally, effects due to responsive hydrogel confinement in a porous template are shown to depend on pore size and architecture of the PSi transducer substrate. Sufficient copolymer and water is removed from the PSi transducer upon dissolution and drying of the hydrogel to induce color changes that can be detected by the unaided eye. This highlights the potential for future development for point-of-care diagnostic biosensing. [source] Living Yeast Cells as a Controllable Biosynthesizer for Fluorescent Quantum DotsADVANCED FUNCTIONAL MATERIALS, Issue 15 2009Ran Cui Abstract There are currently some problems in the field of chemical synthesis, such as environmental impact, energy loss, and safety, that need to be tackled urgently. An interdisciplinary approach, based on different backgrounds, may succeed in solving these problems. Organisms can be chosen as potential platforms for materials fabrication, since biosystems are natural and highly efficient. Here, an example of how to solve some of these chemical problems through biology, namely, through a novel biological strategy of coupling intracellular irrelated biochemical reactions for controllable synthesis of multicolor CdSe quantum dots (QDs) using living yeast cells as a biosynthesizer, is demonstrated. The unique fluorescence properties of CdSe QDs can be utilized to directly and visually judge the biosynthesis phase to fully demonstrate this strategy. By such a method, CdSe QDs, emitting at a variety of single fluorescence wavelengths, can be intracellularly, controllably synthesized at just 30°C instead of at 300°C with combustible, explosive, and toxic organic reagents. This green biosynthetic route is a novel strategy of coupling, with biochemical reactions taking place irrelatedly, both in time and space. It involves a remarkable decrease in reaction temperature, from around 300 °C to 30 °C and excellent color controllability of CdSe photoluminescence. It is well known that to control the size of nanocrystals is a mojor challenge in the biosynthesis of high-quality nanomaterials. The present work demonstrates clearly that biological systems can be creatively utilized to realize controllable unnatural biosynthesis that normally does not exist, offering new insights for sustainable chemistry. [source] On the variability of respiration in terrestrial ecosystems: moving beyond Q10GLOBAL CHANGE BIOLOGY, Issue 2 2006ERIC A. DAVIDSON Abstract Respiration, which is the second most important carbon flux in ecosystems following gross primary productivity, is typically represented in biogeochemical models by simple temperature dependence equations. These equations were established in the 19th century and have been modified very little since then. Recent applications of these equations to data on soil respiration have produced highly variable apparent temperature sensitivities. This paper searches for reasons for this variability, ranging from biochemical reactions to ecosystem-scale substrate supply. For a simple membrane-bound enzymatic system that follows Michaelis,Menten kinetics, the temperature sensitivities of maximum enzyme activity (Vmax) and the half-saturation constant that reflects the affinity of the enzyme for the substrate (Km) can cancel each other to produce no net temperature dependence of the enzyme. Alternatively, when diffusion of substrates covaries with temperature, then the combined temperature sensitivity can be higher than that of each individual process. We also present examples to show that soluble carbon substrate supply is likely to be important at scales ranging from transport across membranes, diffusion through soil water films, allocation to aboveground and belowground plant tissues, phenological patterns of carbon allocation and growth, and intersite differences in productivity. Robust models of soil respiration will require that the direct effects of substrate supply, temperature, and desiccation stress be separated from the indirect effects of temperature and soil water content on substrate diffusion and availability. We speculate that apparent Q10 values of respiration that are significantly above about 2.5 probably indicate that some unidentified process of substrate supply is confounded with observed temperature variation. [source] The normal and cancerous living cellINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 14 2006Janos Ladik Abstract We do not have a definition of the living and cancerous states; we can give only their main characteristics at the different levels of organization: cell, organ, and organism. A simple model is proposed for a normal eukaryotic cell based on Prigogine's equation of chemical kinetics with diffusion. In this model, possibly only a few hundred key biochemical reactions should be selected together with their rate and diffusion constants. To solve these coupled nonlinear partial differential equation systems, it is proposed that the model cell be subdivided into compartments and that the problem be worked out always for one compartment (finite element method). This is possible, since the most important biochemical reactions and reaction cycles occur in different parts of the cell. The solutions (concentrations) obtained in one compartment can be used as input to the other compartments (together with the components entering from the environment). As an example, the problem of 10 reactions and 3 compartments has been solved by discretizing the space coordinates and choosing time steps. The solutions obtained by solving the 10 differential equations directly and by the compartmentalization agree very well. The main obstacles to further progress lie in the right choice of reactions and compartments, as well as in the correct estimation of the rate and diffusion constants, which were measured in only a few cases. If such a model cell can be obtained, the solutions should be investigated to determine (i) for their stability (homeostasis); (ii) whether changing the input concentrations to a larger degree one would obtain a new stationary state showing the characteristics of a precancerous state; and (iii) a method of extracting those input concentrations, or functions of them, which are the most important regulatory parameters. If successful, this would provide a scientific definition of the living state in the normal and cancerous states, respectively, at least at the cell level. Finally, outline is provided showing how the model might be extended to multicellular cases, as well as the main difficulties of such a process. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [source] Isolation and characterization of strains of Flavobacterium columnare from BrazilJOURNAL OF FISH DISEASES, Issue 4 2005H C P Figueiredo Abstract Flavobacterium columnare is an important pathogen of freshwater fish, implicated in skin and gill disease, often causing high mortality. An outbreak of skin disease in fingerling and adult Nile tilapia, Oreochromis niloticus (L.), cultivated in a recirculation system, was investigated. Four strains were isolated and characterized by biochemical reactions, enzyme production, fatty acid profile and analysis of the 16S-23S rDNA intergenic spacer region. All strains were identified as F. columnare. Experimental infection assays with one of these strains (BZ-5-02) were conducted and pathogenicity (by intramuscular route) was demonstrated in Nile tilapia and channel catfish, Ictalurus punctatus (Rafinesque). This is the first report of characterization of Brazilian strains of F. columnare. [source] Scandinavian Clinical practice guidelines for therapeutic hypothermia and post-resuscitation care after cardiac arrestACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2009M. CASTRÉN Background and aim: Sudden cardiac arrest survivors suffer from ischaemic brain injury that may lead to poor neurological outcome and death. The reperfusion injury that occurs is associated with damaging biochemical reactions, which are suppressed by mild therapeutic hypothermia (MTH). In several studies MTH has been proven to be safe, with few complications and improved survival, and is recommended by the International Liaison of Committee on Resuscitation. The aim of this paper is to recommend clinical practice guidelines for MTH treatment after cardiac arrest from the Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI). Methods: Relevant studies were identified after two consensus meetings of the SSAI Task Force on Therapeutic Hypothermia (SSAITFTH) and via literature search of the Cochrane Central Register of Controlled Trials and Medline. Evidence was assessed and consensus opinion was used when high-grade evidence (Grade of Recommendation, GOR) was unavailable. A management strategy was developed as a consensus from the evidence and the protocols in the participating countries. Results and conclusion: Although proven beneficial only for patients with initial ventricular fibrillation (GOR A), the SSAITFTH also recommend MTH after restored spontaneous circulation, if active treatment is chosen, in patients with initial pulseless electrical activity and asystole (GOR D). Normal ethical considerations, premorbid status, total anoxia time and general condition should decide whether active treatment is required or not. MTH should be part of a standardized treatment protocol, and initiated as early as possible after indication and treatment have been decided (GOR E). There is insufficient evidence to make definitive recommendations among techniques to induce MTH, and we do not know the optimal target temperature, duration of cooling and rewarming time. New studies are needed to address the question as to how MTH affects, for example, prognostic factors. [source] Heritabilities and quantitative trait loci for blood gases and blood pH in swineANIMAL GENETICS, Issue 2 2009G. Reiner Summary Maintaining pH and blood gases in a narrow range is essential to sustain normal biochemical reactions. Decreased oxygenation, poor tissue perfusion, disturbance to CO2 expiration, and shortage of HCO3, can lead to metabolic acidosis. This is a common situation in swine, and originates from a broad range of medical conditions. pH and blood gases appear to be under genetic control, and populations with physiological traits closer to the pathological thresholds may be more susceptible to developing pathological conditions. However, little is known about the genetic basis of such traits. We have therefore estimated phenotypic and genetic variability and identified quantitative trait loci (QTL) for pH and blood gases in blood samples from 139 F2 pigs from the Meishan/Pietrain family. Samples were taken before and after challenge with Sarcocystis miescheriana, a protozoan parasite of muscle. Twenty-seven QTL influencing pH and blood gases were identified on nine chromosomes. Five of the QTL were significant on a genome-wide level; 22 QTL were significant on a chromosome-wide level. QTL for pH-associated traits have been mapped to SSC3, 18 and X. QTL associated with CO2 have been detected on SSC6, 7, 8 and 9, and QTL associated with O2 on SSC2 and SSC8. QTL showed specific health/disease patterns that were related to the physiological state of the pigs from day 0, to acute disease (day 14), convalescence (day 28) and chronic disease (day 42). The results demonstrate that pH and blood gases are influenced by multiple chromosomal areas, each with relatively small effects. [source] Basic equations of mass transfer through biocatalytic membrane layerASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2009Endre Nagy Abstract The diffusive and convective mass transport through biocatalytic membrane layer (membrane bioreactor), without and with biochemical reactions, have been investigated. Similarly to the two-film theory for gas-liquid system with diffusive mass transport, only, mass transfer rates have been developed for the biocatalytic membrane layer and for the concentration boundary layer on the feed side of the membrane. Overall mass transfer coefficient has also been defined involving the two-layer, simultaneous mass transfer, namely the mass transfer through the concentration boundary layer and biocatalytic membrane layer. The effect of the convective velocity (Pe number) and the biochemical reaction rate, namely first-order and zero-order reactions as limiting cases of the Monod kinetics, are demonstrated on the mass transfer coefficients accompanied by chemical reaction and on the concentration profiles. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] CFD modeling of subcooling process for beer fermentation liquidASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2009Yuejin Yuan Abstract A model of subcooling process for beer fermentation liquid was established at the base of a computational fluid dynamics (CFD) technique which assumed that all the biochemical reactions were suppressed to a lower extent by the cryogenic condition and their influences on heat and momentum transfer of liquid could be ignored. The subcooling process of fermentation liquid in a cooling tank was simulated, where the temperature was from 10 to , 1 °C. The transient temperature and velocity distributions of the fermentation liquid were obtained by the simulation. The results indicated that the temperature delamination was distinct in the direction of the tank axis, while the temperature gradient was inconspicuous along the radial direction. The fermentation liquid showed a complicated movement including numerous local small circumfluences, which was different from our conventional knowledge. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Novel Propionibacterium infection in cattleAUSTRALIAN VETERINARY JOURNAL, Issue 3 2000JC FORBES-FAULKNER Objective To describe four cases of infection in cattle, from geographically different places, with a presumptive new species of Propionibacterium, which causes granulomatous lesions in the head, thorax, abdomen, pelvic area and skin. Procedure Gross lesions, ranging from 0.5 to 15 cm and detected during routine carcase inspection at the abattoir, were submitted to the laboratory for routine testing in the National Granuloma Submission Program. The bacterium isolated was identified using morphological characteristics, biochemical reactions, cell wall components, products of fermentation and 16S rRNAgene sequencing. Results Gross lesions submitted for examination consisted of a fibrous outer capsule enclosing thick yellow pus-like material. A Gram-Glynn stain of the histological sections revealed colonies of Gram-positive, filamentous, branching bacteria. Bacteriological culture, cell wall analysis, biochemical reactions and 16S rRNA sequencing identified the organism as a Propionibacterium sp closely related to P cyclohexanicum and the P freudenreichii cluster. Conclusion This is the first report of a Propionibacterium sp closely related to P cyclohexanicum and the P freudenreichii cluster associated with extensive granulomatous lesions in cattle in Queensland. Sequencing data are suggestive of a previously undescribed species of the Propionibacterium genus. [source] Calculating apparent equilibrium constants of enzyme-catalyzed reactions at pH 7BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION, Issue 1 2000Robert A. Alberty Apparent equilibrium constants K' of biochemical reactions at pH 7 and standard apparent reduction potentials of half reactions at pH 7 can be calculated using a table of standard transformed Gibbs energies of formation ,fG'o at pH 7. A table is provided for 136 reactants at 25°C, pH 7, and ionic strengths of 0, 0.10, and 0.25 M. Examples are given to illustrate the use of the table. [source] Comment: A biological guide for electromagnetic safety: the stress responseBIOELECTROMAGNETICS, Issue 8 2004Martin Blank Abstract Questions of safety of electromagnetic (EM) fields should be based on relevant biological properties, i.e., specific cellular reactions to potentially harmful stimuli. The stress response is a well documented protective reaction of plant and animal cells to a variety of environmental threats, and it is stimulated by both extremely low frequency (ELF) and radio frequency (RF) EM fields. It involves activation of DNA to initiate synthesis of stress proteins. Thermal and non-thermal stimuli affect different segments of DNA and utilize different biochemical pathways. However, both ELF and RF stimulate the same non-thermal pathway. Since the same biochemical reactions are stimulated in different frequency ranges with very different specific absorption rates (SARs), SAR level is not a valid basis for safety standards. Studies of EM field interactions with DNA and with model systems provide insight into a plausible mechanism that can be effective in ELF and RF ranges. Bioelectromagnetics 25:642,646, 2004. © 2004 Wiley-Liss, Inc. [source] Metabonomic profiling of liver metabolites by gas chromatography,mass spectrometry and its application to characterizing hyperlipidemiaBIOMEDICAL CHROMATOGRAPHY, Issue 3 2010Shenghua Gu Abstract The measurement of metabolites in tissues is of great importance in metabonomic research in the biomedical sciences, providing more relevant information than is available from systemic biofluids. The liver is the most important organ/tissue for most biochemical reactions, and the metabolites in the liver are of great interest to scientists. To develop an optimized extraction method and comprehensive profiling technique for liver metabolites, organic solvents of various compositions were designed using design of experiments to extract metabolites from the liver, and the metabolites were profiled by gas chromatography/time-of-flight mass spectrometry (GC/TOF-MS). The resolved peak areas were processed by principle components analysis, partial least-squares projections to latent structures, and discriminant analysis. The results suggest the highest extraction efficiency was for methanol,water, which maximized the majority of GC/TOF-MS responses. The optimal solvent was applied to extract metabolites in liver of hyperlipidemia hamster and the control. The GC/TOF-MS profiles of liver metabolites showed obvious differences between hyperlipidemic hamsters and controls. A comparison of liver and serum data from the same animals identified common biomarkers and presented complementary information. Our results suggest that liver metabonomics is a valuable technique and that the combined analysis of systematic biofluids and local tissues is meaningful and complementary, recovering more comprehensive metabonomic data than either analysis alone. Copyright © 2009 John Wiley & Sons, Ltd. [source] Phenylnannolones A,C: Biosynthesis of New Secondary Metabolites from the Myxobacterium Nannocystis exedensCHEMBIOCHEM, Issue 18 2008Birgit Ohlendorf Abstract Myxobacteria are gliding bacteria that belong to the ,-Proteobacteria and are known for their unique biosynthetic capabilities. Among myxobacteria, Nannocystis spp. are most closely related to marine myxobacteria and their secondary metabolism has hardly been investigated. Phenylnannolones A (1), B (2) and C (3) were obtained from a culture of Nannocystis exedens that was isolated from the intertidal region of Crete. Compound 1 had inhibitory activity toward the ABCB1 gene product P-glycoprotein and reversed daunorubicin resistance in cultured cancer cells. Phenylnannolone A has an unusual structural architecture; it is composed of an ethyl-substituted polyene chain linked to a pyrone moiety on one side and to a phenyl ring on the other. The investigation of the biosynthesis with labelled precursors revealed acetate, butyrate and phenylalanine as building blocks for 1. The labelling pattern suggested novel biochemical reactions for the biosynthesis of the starter unit. [source] Controlling DNA Polymerization with a Switchable AptamerCHEMBIOCHEM, Issue 14 2007Eike Friedrichs Controllable biochemical reactions. DNA polymerization by Taq polymerase can be controlled by switching an aptamer for Taq Pol between a binding and a nonbinding form. [source] Precursors of Biological Cofactors from Ultraviolet Irradiation of Circumstellar/Interstellar Ice AnaloguesCHEMISTRY - A EUROPEAN JOURNAL, Issue 17 2005Uwe J. Meierhenrich Priv.-Doz. Abstract Biological cofactors include functionalized derivatives of cyclic tetrapyrrole structures that incorporate different metal ions. They build up structural partnerships with proteins, which play a crucial role in biochemical reactions. Porphyrin, chlorin, bacteriochlorin, and corrin are the basic structures of cofactors (heme, chlorophyll, bacteriochlorophyll, siroheme, F 430, and vitamin B12). Laboratory and theoretical work suggest that the molecular building blocks of proteins (,-amino acids) and nucleic acids (carbohydrates, purines, and pyrimidines) were generated under prebiotic conditions. On the other hand, experimental data on the prebiotic chemistry of cofactors are rare. We propose to search directly for the pathways of the formation of cofactors in the laboratory. Herein we report on the detection of N-heterocycles and amines in the room-temperature residue obtained after photo- and thermal processing of an interstellar ice analogue under high vacuum at 12 K. Among them, hexahydro-1,3,5-triazine and its derivatives, together with monopyrrolic molecules, are precursors of porphinoid cofactors. Hexahydropyrimidine was also detected. This is the first detection of these compounds in experiments simulating circumstellar/interstellar conditions. Except for 2-aminopyrrole and 2,4-diaminofuran, which were only found in 13C-labeled experiments, all the reported species were detected in both 12C- and 13C-labeled experiments, excluding contamination. The molecules reported here might be present in circumstellar/interstellar grains and cometary dust and could be detected by the Stardust and Rosetta missions. [source] Glass Transition and Food Technology: A Critical AppraisalJOURNAL OF FOOD SCIENCE, Issue 7 2002M. Le Meste ABSTRACT: Most low water content or frozen food products are partly or fully amorphous. This review will discuss the extent to which it is possible to understand and predict their behavior during processing and storage, on the basis of glass transition temperature values (Tg) and phenomena related to glass transition. Two main conclusions are provisionally proposed. Firstly, glass transition cannot be considered as an absolute threshold for molecular mobility. Transport of water and other small molecules takes place even in the glassy state at a significant rate, resulting in effective exchange of water in multi-domains foods or sensitivity to oxidation of encapsulated materials. Texture properties (crispness) also appear to be greatly affected by sub-Tg relaxations and aging below Tg. Secondly, glass transition is only one among the various factors controlling the kinetics of evolution of products during storage and processing. For processes such as collapse, caking, crystallization, and operations like drying, extrusion, flaking, Tg data and WLF kinetics have good predictive value as regards the effects of temperature and water content. On the contrary, chemical/biochemical reactions are frequently observed at temperature below Tg, albeit at a reduced rate, and WLF kinetics may be obscured by other factors. [source] | |||||||||||||||||||